From b55c33c0cf0857b24be3997951aaedb78f776279 Mon Sep 17 00:00:00 2001 From: V3n3RiX Date: Thu, 30 Oct 2014 13:25:21 +0200 Subject: Somebody called for an exterminator?...starting the big purge of deprecated ebuilds --- ...groups-kconfig-build-bits-for-BFQ-v7-3.10.patch | 103 - ...k-introduce-the-BFQ-v7-I-O-sched-for-3.10.patch | 5969 ------------- ...arly-Queue-Merge-EQM-to-BFQ-v7-for-3.10.0.patch | 1034 --- .../kogaion-sources/files/desktop/3.10-ck1.patch | 8732 -------------------- .../desktop/change-default-console-loglevel.patch | 13 - .../files/desktop/criu-no-expert.patch | 23 - .../desktop/enable_haswell_pstate_driver.patch | 33 - .../set_kogaion_extraversion_in_makefile.patch | 12 - .../files/desktop/uksm-0.1.2.2-for-v3.10.patch | 7064 ---------------- ...rect-invalid-use-of-user-timespec-in-the-.patch | 80 - .../kogaion-sources/kogaion-sources-3.10.25.ebuild | 55 - .../kogaion-sources/kogaion-sources-3.12.10.ebuild | 22 - .../kogaion-sources/kogaion-sources-3.14.20.ebuild | 22 + 13 files changed, 22 insertions(+), 23140 deletions(-) delete mode 100644 sys-kernel/kogaion-sources/files/desktop/0001-block-cgroups-kconfig-build-bits-for-BFQ-v7-3.10.patch delete mode 100644 sys-kernel/kogaion-sources/files/desktop/0002-block-introduce-the-BFQ-v7-I-O-sched-for-3.10.patch delete mode 100644 sys-kernel/kogaion-sources/files/desktop/0003-block-bfq-add-Early-Queue-Merge-EQM-to-BFQ-v7-for-3.10.0.patch delete mode 100644 sys-kernel/kogaion-sources/files/desktop/3.10-ck1.patch delete mode 100644 sys-kernel/kogaion-sources/files/desktop/change-default-console-loglevel.patch delete mode 100644 sys-kernel/kogaion-sources/files/desktop/criu-no-expert.patch delete mode 100644 sys-kernel/kogaion-sources/files/desktop/enable_haswell_pstate_driver.patch delete mode 100644 sys-kernel/kogaion-sources/files/desktop/set_kogaion_extraversion_in_makefile.patch delete mode 100644 sys-kernel/kogaion-sources/files/desktop/uksm-0.1.2.2-for-v3.10.patch delete mode 100644 sys-kernel/kogaion-sources/files/security/0001-x86-x32-Correct-invalid-use-of-user-timespec-in-the-.patch delete mode 100644 sys-kernel/kogaion-sources/kogaion-sources-3.10.25.ebuild delete mode 100644 sys-kernel/kogaion-sources/kogaion-sources-3.12.10.ebuild create mode 100644 sys-kernel/kogaion-sources/kogaion-sources-3.14.20.ebuild (limited to 'sys-kernel/kogaion-sources') diff --git a/sys-kernel/kogaion-sources/files/desktop/0001-block-cgroups-kconfig-build-bits-for-BFQ-v7-3.10.patch b/sys-kernel/kogaion-sources/files/desktop/0001-block-cgroups-kconfig-build-bits-for-BFQ-v7-3.10.patch deleted file mode 100644 index f92978cf..00000000 --- a/sys-kernel/kogaion-sources/files/desktop/0001-block-cgroups-kconfig-build-bits-for-BFQ-v7-3.10.patch +++ /dev/null @@ -1,103 +0,0 @@ -From 3ded69bee018e94b1cf5e13af9ff557f0f61ab30 Mon Sep 17 00:00:00 2001 -From: Arianna Avanzini -Date: Mon, 27 Jan 2014 23:50:08 +0100 -Subject: [PATCH 1/3] block: cgroups, kconfig, build bits for BFQ-v7-3.10 - -Update Kconfig.iosched and do the related Makefile changes to include -kernel configuration options for BFQ. Also add the bfqio controller -to the cgroups subsystem. - -Signed-off-by: Paolo Valente -Signed-off-by: Arianna Avanzini ---- - block/Kconfig.iosched | 32 ++++++++++++++++++++++++++++++++ - block/Makefile | 1 + - include/linux/cgroup_subsys.h | 6 ++++++ - 3 files changed, 39 insertions(+) - -diff --git a/block/Kconfig.iosched b/block/Kconfig.iosched -index 421bef9..8f552ba 100644 ---- a/block/Kconfig.iosched -+++ b/block/Kconfig.iosched -@@ -39,6 +39,27 @@ config CFQ_GROUP_IOSCHED - ---help--- - Enable group IO scheduling in CFQ. - -+config IOSCHED_BFQ -+ tristate "BFQ I/O scheduler" -+ default n -+ ---help--- -+ The BFQ I/O scheduler tries to distribute bandwidth among -+ all processes according to their weights. -+ It aims at distributing the bandwidth as desired, independently of -+ the disk parameters and with any workload. It also tries to -+ guarantee low latency to interactive and soft real-time -+ applications. If compiled built-in (saying Y here), BFQ can -+ be configured to support hierarchical scheduling. -+ -+config CGROUP_BFQIO -+ bool "BFQ hierarchical scheduling support" -+ depends on CGROUPS && IOSCHED_BFQ=y -+ default n -+ ---help--- -+ Enable hierarchical scheduling in BFQ, using the cgroups -+ filesystem interface. The name of the subsystem will be -+ bfqio. -+ - choice - prompt "Default I/O scheduler" - default DEFAULT_CFQ -@@ -52,6 +73,16 @@ choice - config DEFAULT_CFQ - bool "CFQ" if IOSCHED_CFQ=y - -+ config DEFAULT_BFQ -+ bool "BFQ" if IOSCHED_BFQ=y -+ help -+ Selects BFQ as the default I/O scheduler which will be -+ used by default for all block devices. -+ The BFQ I/O scheduler aims at distributing the bandwidth -+ as desired, independently of the disk parameters and with -+ any workload. It also tries to guarantee low latency to -+ interactive and soft real-time applications. -+ - config DEFAULT_NOOP - bool "No-op" - -@@ -61,6 +92,7 @@ config DEFAULT_IOSCHED - string - default "deadline" if DEFAULT_DEADLINE - default "cfq" if DEFAULT_CFQ -+ default "bfq" if DEFAULT_BFQ - default "noop" if DEFAULT_NOOP - - endmenu -diff --git a/block/Makefile b/block/Makefile -index 39b76ba..c0d20fa 100644 ---- a/block/Makefile -+++ b/block/Makefile -@@ -15,6 +15,7 @@ obj-$(CONFIG_BLK_DEV_THROTTLING) += blk-throttle.o - obj-$(CONFIG_IOSCHED_NOOP) += noop-iosched.o - obj-$(CONFIG_IOSCHED_DEADLINE) += deadline-iosched.o - obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o -+obj-$(CONFIG_IOSCHED_BFQ) += bfq-iosched.o - - obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o - obj-$(CONFIG_BLK_DEV_INTEGRITY) += blk-integrity.o -diff --git a/include/linux/cgroup_subsys.h b/include/linux/cgroup_subsys.h -index 6e7ec64..e5e6b0d 100644 ---- a/include/linux/cgroup_subsys.h -+++ b/include/linux/cgroup_subsys.h -@@ -84,3 +84,9 @@ SUBSYS(bcache) - #endif - - /* */ -+ -+#if IS_SUBSYS_ENABLED(CONFIG_CGROUP_BFQIO) -+SUBSYS(bfqio) -+#endif -+ -+/* */ --- -1.8.5.2 - diff --git a/sys-kernel/kogaion-sources/files/desktop/0002-block-introduce-the-BFQ-v7-I-O-sched-for-3.10.patch b/sys-kernel/kogaion-sources/files/desktop/0002-block-introduce-the-BFQ-v7-I-O-sched-for-3.10.patch deleted file mode 100644 index 0a2c5079..00000000 --- a/sys-kernel/kogaion-sources/files/desktop/0002-block-introduce-the-BFQ-v7-I-O-sched-for-3.10.patch +++ /dev/null @@ -1,5969 +0,0 @@ -From d40506359ff7f890adac4bd75541de73044a121e Mon Sep 17 00:00:00 2001 -From: Paolo Valente -Date: Thu, 9 May 2013 19:10:02 +0200 -Subject: [PATCH 2/3] block: introduce the BFQ-v7 I/O sched for 3.10 - -Add the BFQ-v7 I/O scheduler to 3.10. -The general structure is borrowed from CFQ, as much of the code for -handling I/O contexts Over time, several useful features have been -ported from CFQ as well (details in the changelog in README.BFQ). A -(bfq_)queue is associated to each task doing I/O on a device, and each -time a scheduling decision has to be made a queue is selected and served -until it expires. - - - Slices are given in the service domain: tasks are assigned - budgets, measured in number of sectors. Once got the disk, a task - must however consume its assigned budget within a configurable - maximum time (by default, the maximum possible value of the - budgets is automatically computed to comply with this timeout). - This allows the desired latency vs "throughput boosting" tradeoff - to be set. - - - Budgets are scheduled according to a variant of WF2Q+, implemented - using an augmented rb-tree to take eligibility into account while - preserving an O(log N) overall complexity. - - - A low-latency tunable is provided; if enabled, both interactive - and soft real-time applications are guaranteed a very low latency. - - - Latency guarantees are preserved also in the presence of NCQ. - - - Also with flash-based devices, a high throughput is achieved - while still preserving latency guarantees. - - - BFQ features Early Queue Merge (EQM), a sort of fusion of the - cooperating-queue-merging and the preemption mechanisms present - in CFQ. EQM is in fact a unified mechanism that tries to get a - sequential read pattern, and hence a high throughput, with any - set of processes performing interleaved I/O over a contiguous - sequence of sectors. - - - BFQ supports full hierarchical scheduling, exporting a cgroups - interface. Since each node has a full scheduler, each group can - be assigned its own weight. - - - If the cgroups interface is not used, only I/O priorities can be - assigned to processes, with ioprio values mapped to weights - with the relation weight = IOPRIO_BE_NR - ioprio. - - - ioprio classes are served in strict priority order, i.e., lower - priority queues are not served as long as there are higher - priority queues. Among queues in the same class the bandwidth is - distributed in proportion to the weight of each queue. A very - thin extra bandwidth is however guaranteed to the Idle class, to - prevent it from starving. - -Signed-off-by: Paolo Valente -Signed-off-by: Arianna Avanzini ---- - block/bfq-cgroup.c | 885 ++++++++++++++ - block/bfq-ioc.c | 36 + - block/bfq-iosched.c | 3256 +++++++++++++++++++++++++++++++++++++++++++++++++++ - block/bfq-sched.c | 1077 +++++++++++++++++ - block/bfq.h | 612 ++++++++++ - 5 files changed, 5866 insertions(+) - create mode 100644 block/bfq-cgroup.c - create mode 100644 block/bfq-ioc.c - create mode 100644 block/bfq-iosched.c - create mode 100644 block/bfq-sched.c - create mode 100644 block/bfq.h - -diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c -new file mode 100644 -index 0000000..5a117ad ---- /dev/null -+++ b/block/bfq-cgroup.c -@@ -0,0 +1,885 @@ -+/* -+ * BFQ: CGROUPS support. -+ * -+ * Based on ideas and code from CFQ: -+ * Copyright (C) 2003 Jens Axboe -+ * -+ * Copyright (C) 2008 Fabio Checconi -+ * Paolo Valente -+ * -+ * Copyright (C) 2010 Paolo Valente -+ * -+ * Licensed under the GPL-2 as detailed in the accompanying COPYING.BFQ file. -+ */ -+ -+#ifdef CONFIG_CGROUP_BFQIO -+ -+static DEFINE_MUTEX(bfqio_mutex); -+ -+static bool bfqio_is_removed(struct cgroup *cgroup) -+{ -+ return test_bit(CGRP_REMOVED, &cgroup->flags); -+} -+ -+static struct bfqio_cgroup bfqio_root_cgroup = { -+ .weight = BFQ_DEFAULT_GRP_WEIGHT, -+ .ioprio = BFQ_DEFAULT_GRP_IOPRIO, -+ .ioprio_class = BFQ_DEFAULT_GRP_CLASS, -+}; -+ -+static inline void bfq_init_entity(struct bfq_entity *entity, -+ struct bfq_group *bfqg) -+{ -+ entity->weight = entity->new_weight; -+ entity->orig_weight = entity->new_weight; -+ entity->ioprio = entity->new_ioprio; -+ entity->ioprio_class = entity->new_ioprio_class; -+ entity->parent = bfqg->my_entity; -+ entity->sched_data = &bfqg->sched_data; -+} -+ -+static struct bfqio_cgroup *cgroup_to_bfqio(struct cgroup *cgroup) -+{ -+ return container_of(cgroup_subsys_state(cgroup, bfqio_subsys_id), -+ struct bfqio_cgroup, css); -+} -+ -+/* -+ * Search the bfq_group for bfqd into the hash table (by now only a list) -+ * of bgrp. Must be called under rcu_read_lock(). -+ */ -+static struct bfq_group *bfqio_lookup_group(struct bfqio_cgroup *bgrp, -+ struct bfq_data *bfqd) -+{ -+ struct bfq_group *bfqg; -+ void *key; -+ -+ hlist_for_each_entry_rcu(bfqg, &bgrp->group_data, group_node) { -+ key = rcu_dereference(bfqg->bfqd); -+ if (key == bfqd) -+ return bfqg; -+ } -+ -+ return NULL; -+} -+ -+static inline void bfq_group_init_entity(struct bfqio_cgroup *bgrp, -+ struct bfq_group *bfqg) -+{ -+ struct bfq_entity *entity = &bfqg->entity; -+ -+ /* -+ * If the weight of the entity has never been set via the sysfs -+ * interface, then bgrp->weight == 0. In this case we initialize -+ * the weight from the current ioprio value. Otherwise, the group -+ * weight, if set, has priority over the ioprio value. -+ */ -+ if (bgrp->weight == 0) { -+ entity->new_weight = bfq_ioprio_to_weight(bgrp->ioprio); -+ entity->new_ioprio = bgrp->ioprio; -+ } else { -+ entity->new_weight = bgrp->weight; -+ entity->new_ioprio = bfq_weight_to_ioprio(bgrp->weight); -+ } -+ entity->orig_weight = entity->weight = entity->new_weight; -+ entity->ioprio = entity->new_ioprio; -+ entity->ioprio_class = entity->new_ioprio_class = bgrp->ioprio_class; -+ entity->my_sched_data = &bfqg->sched_data; -+} -+ -+static inline void bfq_group_set_parent(struct bfq_group *bfqg, -+ struct bfq_group *parent) -+{ -+ struct bfq_entity *entity; -+ -+ BUG_ON(parent == NULL); -+ BUG_ON(bfqg == NULL); -+ -+ entity = &bfqg->entity; -+ entity->parent = parent->my_entity; -+ entity->sched_data = &parent->sched_data; -+} -+ -+/** -+ * bfq_group_chain_alloc - allocate a chain of groups. -+ * @bfqd: queue descriptor. -+ * @cgroup: the leaf cgroup this chain starts from. -+ * -+ * Allocate a chain of groups starting from the one belonging to -+ * @cgroup up to the root cgroup. Stop if a cgroup on the chain -+ * to the root has already an allocated group on @bfqd. -+ */ -+static struct bfq_group *bfq_group_chain_alloc(struct bfq_data *bfqd, -+ struct cgroup *cgroup) -+{ -+ struct bfqio_cgroup *bgrp; -+ struct bfq_group *bfqg, *prev = NULL, *leaf = NULL; -+ -+ for (; cgroup != NULL; cgroup = cgroup->parent) { -+ bgrp = cgroup_to_bfqio(cgroup); -+ -+ bfqg = bfqio_lookup_group(bgrp, bfqd); -+ if (bfqg != NULL) { -+ /* -+ * All the cgroups in the path from there to the -+ * root must have a bfq_group for bfqd, so we don't -+ * need any more allocations. -+ */ -+ break; -+ } -+ -+ bfqg = kzalloc(sizeof(*bfqg), GFP_ATOMIC); -+ if (bfqg == NULL) -+ goto cleanup; -+ -+ bfq_group_init_entity(bgrp, bfqg); -+ bfqg->my_entity = &bfqg->entity; -+ -+ if (leaf == NULL) { -+ leaf = bfqg; -+ prev = leaf; -+ } else { -+ bfq_group_set_parent(prev, bfqg); -+ /* -+ * Build a list of allocated nodes using the bfqd -+ * filed, that is still unused and will be initialized -+ * only after the node will be connected. -+ */ -+ prev->bfqd = bfqg; -+ prev = bfqg; -+ } -+ } -+ -+ return leaf; -+ -+cleanup: -+ while (leaf != NULL) { -+ prev = leaf; -+ leaf = leaf->bfqd; -+ kfree(prev); -+ } -+ -+ return NULL; -+} -+ -+/** -+ * bfq_group_chain_link - link an allocatd group chain to a cgroup hierarchy. -+ * @bfqd: the queue descriptor. -+ * @cgroup: the leaf cgroup to start from. -+ * @leaf: the leaf group (to be associated to @cgroup). -+ * -+ * Try to link a chain of groups to a cgroup hierarchy, connecting the -+ * nodes bottom-up, so we can be sure that when we find a cgroup in the -+ * hierarchy that already as a group associated to @bfqd all the nodes -+ * in the path to the root cgroup have one too. -+ * -+ * On locking: the queue lock protects the hierarchy (there is a hierarchy -+ * per device) while the bfqio_cgroup lock protects the list of groups -+ * belonging to the same cgroup. -+ */ -+static void bfq_group_chain_link(struct bfq_data *bfqd, struct cgroup *cgroup, -+ struct bfq_group *leaf) -+{ -+ struct bfqio_cgroup *bgrp; -+ struct bfq_group *bfqg, *next, *prev = NULL; -+ unsigned long flags; -+ -+ assert_spin_locked(bfqd->queue->queue_lock); -+ -+ for (; cgroup != NULL && leaf != NULL; cgroup = cgroup->parent) { -+ bgrp = cgroup_to_bfqio(cgroup); -+ next = leaf->bfqd; -+ -+ bfqg = bfqio_lookup_group(bgrp, bfqd); -+ BUG_ON(bfqg != NULL); -+ -+ spin_lock_irqsave(&bgrp->lock, flags); -+ -+ rcu_assign_pointer(leaf->bfqd, bfqd); -+ hlist_add_head_rcu(&leaf->group_node, &bgrp->group_data); -+ hlist_add_head(&leaf->bfqd_node, &bfqd->group_list); -+ -+ spin_unlock_irqrestore(&bgrp->lock, flags); -+ -+ prev = leaf; -+ leaf = next; -+ } -+ -+ BUG_ON(cgroup == NULL && leaf != NULL); -+ if (cgroup != NULL && prev != NULL) { -+ bgrp = cgroup_to_bfqio(cgroup); -+ bfqg = bfqio_lookup_group(bgrp, bfqd); -+ bfq_group_set_parent(prev, bfqg); -+ } -+} -+ -+/** -+ * bfq_find_alloc_group - return the group associated to @bfqd in @cgroup. -+ * @bfqd: queue descriptor. -+ * @cgroup: cgroup being searched for. -+ * -+ * Return a group associated to @bfqd in @cgroup, allocating one if -+ * necessary. When a group is returned all the cgroups in the path -+ * to the root have a group associated to @bfqd. -+ * -+ * If the allocation fails, return the root group: this breaks guarantees -+ * but is a safe fallbak. If this loss becames a problem it can be -+ * mitigated using the equivalent weight (given by the product of the -+ * weights of the groups in the path from @group to the root) in the -+ * root scheduler. -+ * -+ * We allocate all the missing nodes in the path from the leaf cgroup -+ * to the root and we connect the nodes only after all the allocations -+ * have been successful. -+ */ -+static struct bfq_group *bfq_find_alloc_group(struct bfq_data *bfqd, -+ struct cgroup *cgroup) -+{ -+ struct bfqio_cgroup *bgrp = cgroup_to_bfqio(cgroup); -+ struct bfq_group *bfqg; -+ -+ bfqg = bfqio_lookup_group(bgrp, bfqd); -+ if (bfqg != NULL) -+ return bfqg; -+ -+ bfqg = bfq_group_chain_alloc(bfqd, cgroup); -+ if (bfqg != NULL) -+ bfq_group_chain_link(bfqd, cgroup, bfqg); -+ else -+ bfqg = bfqd->root_group; -+ -+ return bfqg; -+} -+ -+/** -+ * bfq_bfqq_move - migrate @bfqq to @bfqg. -+ * @bfqd: queue descriptor. -+ * @bfqq: the queue to move. -+ * @entity: @bfqq's entity. -+ * @bfqg: the group to move to. -+ * -+ * Move @bfqq to @bfqg, deactivating it from its old group and reactivating -+ * it on the new one. Avoid putting the entity on the old group idle tree. -+ * -+ * Must be called under the queue lock; the cgroup owning @bfqg must -+ * not disappear (by now this just means that we are called under -+ * rcu_read_lock()). -+ */ -+static void bfq_bfqq_move(struct bfq_data *bfqd, struct bfq_queue *bfqq, -+ struct bfq_entity *entity, struct bfq_group *bfqg) -+{ -+ int busy, resume; -+ -+ busy = bfq_bfqq_busy(bfqq); -+ resume = !RB_EMPTY_ROOT(&bfqq->sort_list); -+ -+ BUG_ON(resume && !entity->on_st); -+ BUG_ON(busy && !resume && entity->on_st && -+ bfqq != bfqd->in_service_queue); -+ -+ if (busy) { -+ BUG_ON(atomic_read(&bfqq->ref) < 2); -+ -+ if (!resume) -+ bfq_del_bfqq_busy(bfqd, bfqq, 0); -+ else -+ bfq_deactivate_bfqq(bfqd, bfqq, 0); -+ } else if (entity->on_st) -+ bfq_put_idle_entity(bfq_entity_service_tree(entity), entity); -+ -+ /* -+ * Here we use a reference to bfqg. We don't need a refcounter -+ * as the cgroup reference will not be dropped, so that its -+ * destroy() callback will not be invoked. -+ */ -+ entity->parent = bfqg->my_entity; -+ entity->sched_data = &bfqg->sched_data; -+ -+ if (busy && resume) -+ bfq_activate_bfqq(bfqd, bfqq); -+ -+ if (bfqd->in_service_queue == NULL && !bfqd->rq_in_driver) -+ bfq_schedule_dispatch(bfqd); -+} -+ -+/** -+ * __bfq_bic_change_cgroup - move @bic to @cgroup. -+ * @bfqd: the queue descriptor. -+ * @bic: the bic to move. -+ * @cgroup: the cgroup to move to. -+ * -+ * Move bic to cgroup, assuming that bfqd->queue is locked; the caller -+ * has to make sure that the reference to cgroup is valid across the call. -+ * -+ * NOTE: an alternative approach might have been to store the current -+ * cgroup in bfqq and getting a reference to it, reducing the lookup -+ * time here, at the price of slightly more complex code. -+ */ -+static struct bfq_group *__bfq_bic_change_cgroup(struct bfq_data *bfqd, -+ struct bfq_io_cq *bic, -+ struct cgroup *cgroup) -+{ -+ struct bfq_queue *async_bfqq = bic_to_bfqq(bic, 0); -+ struct bfq_queue *sync_bfqq = bic_to_bfqq(bic, 1); -+ struct bfq_entity *entity; -+ struct bfq_group *bfqg; -+ struct bfqio_cgroup *bgrp; -+ -+ bgrp = cgroup_to_bfqio(cgroup); -+ -+ bfqg = bfq_find_alloc_group(bfqd, cgroup); -+ if (async_bfqq != NULL) { -+ entity = &async_bfqq->entity; -+ -+ if (entity->sched_data != &bfqg->sched_data) { -+ bic_set_bfqq(bic, NULL, 0); -+ bfq_log_bfqq(bfqd, async_bfqq, -+ "bic_change_group: %p %d", -+ async_bfqq, atomic_read(&async_bfqq->ref)); -+ bfq_put_queue(async_bfqq); -+ } -+ } -+ -+ if (sync_bfqq != NULL) { -+ entity = &sync_bfqq->entity; -+ if (entity->sched_data != &bfqg->sched_data) -+ bfq_bfqq_move(bfqd, sync_bfqq, entity, bfqg); -+ } -+ -+ return bfqg; -+} -+ -+/** -+ * bfq_bic_change_cgroup - move @bic to @cgroup. -+ * @bic: the bic being migrated. -+ * @cgroup: the destination cgroup. -+ * -+ * When the task owning @bic is moved to @cgroup, @bic is immediately -+ * moved into its new parent group. -+ */ -+static void bfq_bic_change_cgroup(struct bfq_io_cq *bic, -+ struct cgroup *cgroup) -+{ -+ struct bfq_data *bfqd; -+ unsigned long uninitialized_var(flags); -+ -+ bfqd = bfq_get_bfqd_locked(&(bic->icq.q->elevator->elevator_data), -+ &flags); -+ if (bfqd != NULL) { -+ __bfq_bic_change_cgroup(bfqd, bic, cgroup); -+ bfq_put_bfqd_unlock(bfqd, &flags); -+ } -+} -+ -+/** -+ * bfq_bic_update_cgroup - update the cgroup of @bic. -+ * @bic: the @bic to update. -+ * -+ * Make sure that @bic is enqueued in the cgroup of the current task. -+ * We need this in addition to moving bics during the cgroup attach -+ * phase because the task owning @bic could be at its first disk -+ * access or we may end up in the root cgroup as the result of a -+ * memory allocation failure and here we try to move to the right -+ * group. -+ * -+ * Must be called under the queue lock. It is safe to use the returned -+ * value even after the rcu_read_unlock() as the migration/destruction -+ * paths act under the queue lock too. IOW it is impossible to race with -+ * group migration/destruction and end up with an invalid group as: -+ * a) here cgroup has not yet been destroyed, nor its destroy callback -+ * has started execution, as current holds a reference to it, -+ * b) if it is destroyed after rcu_read_unlock() [after current is -+ * migrated to a different cgroup] its attach() callback will have -+ * taken care of remove all the references to the old cgroup data. -+ */ -+static struct bfq_group *bfq_bic_update_cgroup(struct bfq_io_cq *bic) -+{ -+ struct bfq_data *bfqd = bic_to_bfqd(bic); -+ struct bfq_group *bfqg; -+ struct cgroup *cgroup; -+ -+ BUG_ON(bfqd == NULL); -+ -+ rcu_read_lock(); -+ cgroup = task_cgroup(current, bfqio_subsys_id); -+ bfqg = __bfq_bic_change_cgroup(bfqd, bic, cgroup); -+ rcu_read_unlock(); -+ -+ return bfqg; -+} -+ -+/** -+ * bfq_flush_idle_tree - deactivate any entity on the idle tree of @st. -+ * @st: the service tree being flushed. -+ */ -+static inline void bfq_flush_idle_tree(struct bfq_service_tree *st) -+{ -+ struct bfq_entity *entity = st->first_idle; -+ -+ for (; entity != NULL; entity = st->first_idle) -+ __bfq_deactivate_entity(entity, 0); -+} -+ -+/** -+ * bfq_reparent_leaf_entity - move leaf entity to the root_group. -+ * @bfqd: the device data structure with the root group. -+ * @entity: the entity to move. -+ */ -+static inline void bfq_reparent_leaf_entity(struct bfq_data *bfqd, -+ struct bfq_entity *entity) -+{ -+ struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); -+ -+ BUG_ON(bfqq == NULL); -+ bfq_bfqq_move(bfqd, bfqq, entity, bfqd->root_group); -+ return; -+} -+ -+/** -+ * bfq_reparent_active_entities - move to the root group all active entities. -+ * @bfqd: the device data structure with the root group. -+ * @bfqg: the group to move from. -+ * @st: the service tree with the entities. -+ * -+ * Needs queue_lock to be taken and reference to be valid over the call. -+ */ -+static inline void bfq_reparent_active_entities(struct bfq_data *bfqd, -+ struct bfq_group *bfqg, -+ struct bfq_service_tree *st) -+{ -+ struct rb_root *active = &st->active; -+ struct bfq_entity *entity = NULL; -+ -+ if (!RB_EMPTY_ROOT(&st->active)) -+ entity = bfq_entity_of(rb_first(active)); -+ -+ for (; entity != NULL; entity = bfq_entity_of(rb_first(active))) -+ bfq_reparent_leaf_entity(bfqd, entity); -+ -+ if (bfqg->sched_data.active_entity != NULL) -+ bfq_reparent_leaf_entity(bfqd, bfqg->sched_data.active_entity); -+ -+ return; -+} -+ -+/** -+ * bfq_destroy_group - destroy @bfqg. -+ * @bgrp: the bfqio_cgroup containing @bfqg. -+ * @bfqg: the group being destroyed. -+ * -+ * Destroy @bfqg, making sure that it is not referenced from its parent. -+ */ -+static void bfq_destroy_group(struct bfqio_cgroup *bgrp, struct bfq_group *bfqg) -+{ -+ struct bfq_data *bfqd; -+ struct bfq_service_tree *st; -+ struct bfq_entity *entity = bfqg->my_entity; -+ unsigned long uninitialized_var(flags); -+ int i; -+ -+ hlist_del(&bfqg->group_node); -+ -+ /* -+ * Empty all service_trees belonging to this group before deactivating -+ * the group itself. -+ */ -+ for (i = 0; i < BFQ_IOPRIO_CLASSES; i++) { -+ st = bfqg->sched_data.service_tree + i; -+ -+ /* -+ * The idle tree may still contain bfq_queues belonging -+ * to exited task because they never migrated to a different -+ * cgroup from the one being destroyed now. Noone else -+ * can access them so it's safe to act without any lock. -+ */ -+ bfq_flush_idle_tree(st); -+ -+ /* -+ * It may happen that some queues are still active -+ * (busy) upon group destruction (if the corresponding -+ * processes have been forced to terminate). We move -+ * all the leaf entities corresponding to these queues -+ * to the root_group. -+ * Also, it may happen that the group has an entity -+ * under service, which is disconnected from the active -+ * tree: it must be moved, too. -+ * There is no need to put the sync queues, as the -+ * scheduler has taken no reference. -+ */ -+ bfqd = bfq_get_bfqd_locked(&bfqg->bfqd, &flags); -+ if (bfqd != NULL) { -+ bfq_reparent_active_entities(bfqd, bfqg, st); -+ bfq_put_bfqd_unlock(bfqd, &flags); -+ } -+ BUG_ON(!RB_EMPTY_ROOT(&st->active)); -+ BUG_ON(!RB_EMPTY_ROOT(&st->idle)); -+ } -+ BUG_ON(bfqg->sched_data.next_active != NULL); -+ BUG_ON(bfqg->sched_data.active_entity != NULL); -+ -+ /* -+ * We may race with device destruction, take extra care when -+ * dereferencing bfqg->bfqd. -+ */ -+ bfqd = bfq_get_bfqd_locked(&bfqg->bfqd, &flags); -+ if (bfqd != NULL) { -+ hlist_del(&bfqg->bfqd_node); -+ __bfq_deactivate_entity(entity, 0); -+ bfq_put_async_queues(bfqd, bfqg); -+ bfq_put_bfqd_unlock(bfqd, &flags); -+ } -+ BUG_ON(entity->tree != NULL); -+ -+ /* -+ * No need to defer the kfree() to the end of the RCU grace -+ * period: we are called from the destroy() callback of our -+ * cgroup, so we can be sure that noone is a) still using -+ * this cgroup or b) doing lookups in it. -+ */ -+ kfree(bfqg); -+} -+ -+static void bfq_end_raising_async(struct bfq_data *bfqd) -+{ -+ struct hlist_node *tmp; -+ struct bfq_group *bfqg; -+ -+ hlist_for_each_entry_safe(bfqg, tmp, &bfqd->group_list, bfqd_node) -+ bfq_end_raising_async_queues(bfqd, bfqg); -+ bfq_end_raising_async_queues(bfqd, bfqd->root_group); -+} -+ -+/** -+ * bfq_disconnect_groups - diconnect @bfqd from all its groups. -+ * @bfqd: the device descriptor being exited. -+ * -+ * When the device exits we just make sure that no lookup can return -+ * the now unused group structures. They will be deallocated on cgroup -+ * destruction. -+ */ -+static void bfq_disconnect_groups(struct bfq_data *bfqd) -+{ -+ struct hlist_node *tmp; -+ struct bfq_group *bfqg; -+ -+ bfq_log(bfqd, "disconnect_groups beginning"); -+ hlist_for_each_entry_safe(bfqg, tmp, &bfqd->group_list, bfqd_node) { -+ hlist_del(&bfqg->bfqd_node); -+ -+ __bfq_deactivate_entity(bfqg->my_entity, 0); -+ -+ /* -+ * Don't remove from the group hash, just set an -+ * invalid key. No lookups can race with the -+ * assignment as bfqd is being destroyed; this -+ * implies also that new elements cannot be added -+ * to the list. -+ */ -+ rcu_assign_pointer(bfqg->bfqd, NULL); -+ -+ bfq_log(bfqd, "disconnect_groups: put async for group %p", -+ bfqg); -+ bfq_put_async_queues(bfqd, bfqg); -+ } -+} -+ -+static inline void bfq_free_root_group(struct bfq_data *bfqd) -+{ -+ struct bfqio_cgroup *bgrp = &bfqio_root_cgroup; -+ struct bfq_group *bfqg = bfqd->root_group; -+ -+ bfq_put_async_queues(bfqd, bfqg); -+ -+ spin_lock_irq(&bgrp->lock); -+ hlist_del_rcu(&bfqg->group_node); -+ spin_unlock_irq(&bgrp->lock); -+ -+ /* -+ * No need to synchronize_rcu() here: since the device is gone -+ * there cannot be any read-side access to its root_group. -+ */ -+ kfree(bfqg); -+} -+ -+static struct bfq_group *bfq_alloc_root_group(struct bfq_data *bfqd, int node) -+{ -+ struct bfq_group *bfqg; -+ struct bfqio_cgroup *bgrp; -+ int i; -+ -+ bfqg = kzalloc_node(sizeof(*bfqg), GFP_KERNEL, node); -+ if (bfqg == NULL) -+ return NULL; -+ -+ bfqg->entity.parent = NULL; -+ for (i = 0; i < BFQ_IOPRIO_CLASSES; i++) -+ bfqg->sched_data.service_tree[i] = BFQ_SERVICE_TREE_INIT; -+ -+ bgrp = &bfqio_root_cgroup; -+ spin_lock_irq(&bgrp->lock); -+ rcu_assign_pointer(bfqg->bfqd, bfqd); -+ hlist_add_head_rcu(&bfqg->group_node, &bgrp->group_data); -+ spin_unlock_irq(&bgrp->lock); -+ -+ return bfqg; -+} -+ -+#define SHOW_FUNCTION(__VAR) \ -+static u64 bfqio_cgroup_##__VAR##_read(struct cgroup *cgroup, \ -+ struct cftype *cftype) \ -+{ \ -+ struct bfqio_cgroup *bgrp; \ -+ u64 ret = -ENODEV; \ -+ \ -+ mutex_lock(&bfqio_mutex); \ -+ if (bfqio_is_removed(cgroup)) \ -+ goto out_unlock; \ -+ \ -+ bgrp = cgroup_to_bfqio(cgroup); \ -+ spin_lock_irq(&bgrp->lock); \ -+ ret = bgrp->__VAR; \ -+ spin_unlock_irq(&bgrp->lock); \ -+ \ -+out_unlock: \ -+ mutex_unlock(&bfqio_mutex); \ -+ return ret; \ -+} -+ -+SHOW_FUNCTION(weight); -+SHOW_FUNCTION(ioprio); -+SHOW_FUNCTION(ioprio_class); -+#undef SHOW_FUNCTION -+ -+#define STORE_FUNCTION(__VAR, __MIN, __MAX) \ -+static int bfqio_cgroup_##__VAR##_write(struct cgroup *cgroup, \ -+ struct cftype *cftype, \ -+ u64 val) \ -+{ \ -+ struct bfqio_cgroup *bgrp; \ -+ struct bfq_group *bfqg; \ -+ int ret = -EINVAL; \ -+ \ -+ if (val < (__MIN) || val > (__MAX)) \ -+ return ret; \ -+ \ -+ ret = -ENODEV; \ -+ mutex_lock(&bfqio_mutex); \ -+ if (bfqio_is_removed(cgroup)) \ -+ goto out_unlock; \ -+ ret = 0; \ -+ \ -+ bgrp = cgroup_to_bfqio(cgroup); \ -+ \ -+ spin_lock_irq(&bgrp->lock); \ -+ bgrp->__VAR = (unsigned short)val; \ -+ hlist_for_each_entry(bfqg, &bgrp->group_data, group_node) { \ -+ /* \ -+ * Setting the ioprio_changed flag of the entity \ -+ * to 1 with new_##__VAR == ##__VAR would re-set \ -+ * the value of the weight to its ioprio mapping. \ -+ * Set the flag only if necessary. \ -+ */ \ -+ if ((unsigned short)val != bfqg->entity.new_##__VAR) { \ -+ bfqg->entity.new_##__VAR = (unsigned short)val; \ -+ smp_wmb(); \ -+ bfqg->entity.ioprio_changed = 1; \ -+ } \ -+ } \ -+ spin_unlock_irq(&bgrp->lock); \ -+ \ -+out_unlock: \ -+ mutex_unlock(&bfqio_mutex); \ -+ return ret; \ -+} -+ -+STORE_FUNCTION(weight, BFQ_MIN_WEIGHT, BFQ_MAX_WEIGHT); -+STORE_FUNCTION(ioprio, 0, IOPRIO_BE_NR - 1); -+STORE_FUNCTION(ioprio_class, IOPRIO_CLASS_RT, IOPRIO_CLASS_IDLE); -+#undef STORE_FUNCTION -+ -+static struct cftype bfqio_files[] = { -+ { -+ .name = "weight", -+ .read_u64 = bfqio_cgroup_weight_read, -+ .write_u64 = bfqio_cgroup_weight_write, -+ }, -+ { -+ .name = "ioprio", -+ .read_u64 = bfqio_cgroup_ioprio_read, -+ .write_u64 = bfqio_cgroup_ioprio_write, -+ }, -+ { -+ .name = "ioprio_class", -+ .read_u64 = bfqio_cgroup_ioprio_class_read, -+ .write_u64 = bfqio_cgroup_ioprio_class_write, -+ }, -+ { }, /* terminate */ -+}; -+ -+static struct cgroup_subsys_state *bfqio_create(struct cgroup *cgroup) -+{ -+ struct bfqio_cgroup *bgrp; -+ -+ if (cgroup->parent != NULL) { -+ bgrp = kzalloc(sizeof(*bgrp), GFP_KERNEL); -+ if (bgrp == NULL) -+ return ERR_PTR(-ENOMEM); -+ } else -+ bgrp = &bfqio_root_cgroup; -+ -+ spin_lock_init(&bgrp->lock); -+ INIT_HLIST_HEAD(&bgrp->group_data); -+ bgrp->ioprio = BFQ_DEFAULT_GRP_IOPRIO; -+ bgrp->ioprio_class = BFQ_DEFAULT_GRP_CLASS; -+ -+ return &bgrp->css; -+} -+ -+/* -+ * We cannot support shared io contexts, as we have no means to support -+ * two tasks with the same ioc in two different groups without major rework -+ * of the main bic/bfqq data structures. By now we allow a task to change -+ * its cgroup only if it's the only owner of its ioc; the drawback of this -+ * behavior is that a group containing a task that forked using CLONE_IO -+ * will not be destroyed until the tasks sharing the ioc die. -+ */ -+static int bfqio_can_attach(struct cgroup *cgroup, struct cgroup_taskset *tset) -+{ -+ struct task_struct *task; -+ struct io_context *ioc; -+ int ret = 0; -+ -+ cgroup_taskset_for_each(task, cgroup, tset) { -+ /* task_lock() is needed to avoid races with exit_io_context() */ -+ task_lock(task); -+ ioc = task->io_context; -+ if (ioc != NULL && atomic_read(&ioc->nr_tasks) > 1) -+ /* -+ * ioc == NULL means that the task is either too young or -+ * exiting: if it has still no ioc the ioc can't be shared, -+ * if the task is exiting the attach will fail anyway, no -+ * matter what we return here. -+ */ -+ ret = -EINVAL; -+ task_unlock(task); -+ if (ret) -+ break; -+ } -+ -+ return ret; -+} -+ -+static void bfqio_attach(struct cgroup *cgroup, struct cgroup_taskset *tset) -+{ -+ struct task_struct *task; -+ struct io_context *ioc; -+ struct io_cq *icq; -+ -+ /* -+ * IMPORTANT NOTE: The move of more than one process at a time to a -+ * new group has not yet been tested. -+ */ -+ cgroup_taskset_for_each(task, cgroup, tset) { -+ ioc = get_task_io_context(task, GFP_ATOMIC, NUMA_NO_NODE); -+ if (ioc) { -+ /* -+ * Handle cgroup change here. -+ */ -+ rcu_read_lock(); -+ hlist_for_each_entry_rcu(icq, &ioc->icq_list, ioc_node) -+ if (!strncmp( -+ icq->q->elevator->type->elevator_name, -+ "bfq", ELV_NAME_MAX)) -+ bfq_bic_change_cgroup(icq_to_bic(icq), -+ cgroup); -+ rcu_read_unlock(); -+ put_io_context(ioc); -+ } -+ } -+} -+ -+static void bfqio_destroy(struct cgroup *cgroup) -+{ -+ struct bfqio_cgroup *bgrp = cgroup_to_bfqio(cgroup); -+ struct hlist_node *tmp; -+ struct bfq_group *bfqg; -+ -+ /* -+ * Since we are destroying the cgroup, there are no more tasks -+ * referencing it, and all the RCU grace periods that may have -+ * referenced it are ended (as the destruction of the parent -+ * cgroup is RCU-safe); bgrp->group_data will not be accessed by -+ * anything else and we don't need any synchronization. -+ */ -+ hlist_for_each_entry_safe(bfqg, tmp, &bgrp->group_data, group_node) -+ bfq_destroy_group(bgrp, bfqg); -+ -+ BUG_ON(!hlist_empty(&bgrp->group_data)); -+ -+ kfree(bgrp); -+} -+ -+struct cgroup_subsys bfqio_subsys = { -+ .name = "bfqio", -+ .css_alloc = bfqio_create, -+ .can_attach = bfqio_can_attach, -+ .attach = bfqio_attach, -+ .css_free = bfqio_destroy, -+ .subsys_id = bfqio_subsys_id, -+ .base_cftypes = bfqio_files, -+}; -+#else -+static inline void bfq_init_entity(struct bfq_entity *entity, -+ struct bfq_group *bfqg) -+{ -+ entity->weight = entity->new_weight; -+ entity->orig_weight = entity->new_weight; -+ entity->ioprio = entity->new_ioprio; -+ entity->ioprio_class = entity->new_ioprio_class; -+ entity->sched_data = &bfqg->sched_data; -+} -+ -+static inline struct bfq_group * -+bfq_bic_update_cgroup(struct bfq_io_cq *bic) -+{ -+ struct bfq_data *bfqd = bic_to_bfqd(bic); -+ return bfqd->root_group; -+} -+ -+static inline void bfq_bfqq_move(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq, -+ struct bfq_entity *entity, -+ struct bfq_group *bfqg) -+{ -+} -+ -+static void bfq_end_raising_async(struct bfq_data *bfqd) -+{ -+ bfq_end_raising_async_queues(bfqd, bfqd->root_group); -+} -+ -+static inline void bfq_disconnect_groups(struct bfq_data *bfqd) -+{ -+ bfq_put_async_queues(bfqd, bfqd->root_group); -+} -+ -+static inline void bfq_free_root_group(struct bfq_data *bfqd) -+{ -+ kfree(bfqd->root_group); -+} -+ -+static struct bfq_group *bfq_alloc_root_group(struct bfq_data *bfqd, int node) -+{ -+ struct bfq_group *bfqg; -+ int i; -+ -+ bfqg = kmalloc_node(sizeof(*bfqg), GFP_KERNEL | __GFP_ZERO, node); -+ if (bfqg == NULL) -+ return NULL; -+ -+ for (i = 0; i < BFQ_IOPRIO_CLASSES; i++) -+ bfqg->sched_data.service_tree[i] = BFQ_SERVICE_TREE_INIT; -+ -+ return bfqg; -+} -+#endif -diff --git a/block/bfq-ioc.c b/block/bfq-ioc.c -new file mode 100644 -index 0000000..7f6b000 ---- /dev/null -+++ b/block/bfq-ioc.c -@@ -0,0 +1,36 @@ -+/* -+ * BFQ: I/O context handling. -+ * -+ * Based on ideas and code from CFQ: -+ * Copyright (C) 2003 Jens Axboe -+ * -+ * Copyright (C) 2008 Fabio Checconi -+ * Paolo Valente -+ * -+ * Copyright (C) 2010 Paolo Valente -+ */ -+ -+/** -+ * icq_to_bic - convert iocontext queue structure to bfq_io_cq. -+ * @icq: the iocontext queue. -+ */ -+static inline struct bfq_io_cq *icq_to_bic(struct io_cq *icq) -+{ -+ /* bic->icq is the first member, %NULL will convert to %NULL */ -+ return container_of(icq, struct bfq_io_cq, icq); -+} -+ -+/** -+ * bfq_bic_lookup - search into @ioc a bic associated to @bfqd. -+ * @bfqd: the lookup key. -+ * @ioc: the io_context of the process doing I/O. -+ * -+ * Queue lock must be held. -+ */ -+static inline struct bfq_io_cq *bfq_bic_lookup(struct bfq_data *bfqd, -+ struct io_context *ioc) -+{ -+ if (ioc) -+ return icq_to_bic(ioc_lookup_icq(ioc, bfqd->queue)); -+ return NULL; -+} -diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c -new file mode 100644 -index 0000000..96abb81 ---- /dev/null -+++ b/block/bfq-iosched.c -@@ -0,0 +1,3256 @@ -+/* -+ * BFQ, or Budget Fair Queueing, disk scheduler. -+ * -+ * Based on ideas and code from CFQ: -+ * Copyright (C) 2003 Jens Axboe -+ * -+ * Copyright (C) 2008 Fabio Checconi -+ * Paolo Valente -+ * -+ * Copyright (C) 2010 Paolo Valente -+ * -+ * Licensed under the GPL-2 as detailed in the accompanying COPYING.BFQ file. -+ * -+ * BFQ is a proportional share disk scheduling algorithm based on the -+ * slice-by-slice service scheme of CFQ. But BFQ assigns budgets, measured in -+ * number of sectors, to tasks instead of time slices. The disk is not granted -+ * to the in-service task for a given time slice, but until it has exahusted -+ * its assigned budget. This change from the time to the service domain allows -+ * BFQ to distribute the disk bandwidth among tasks as desired, without any -+ * distortion due to ZBR, workload fluctuations or other factors. BFQ uses an -+ * ad hoc internal scheduler, called B-WF2Q+, to schedule tasks according to -+ * their budgets (more precisely BFQ schedules queues associated to tasks). -+ * Thanks to this accurate scheduler, BFQ can afford to assign high budgets to -+ * disk-bound non-seeky tasks (to boost the throughput), and yet guarantee low -+ * latencies to interactive and soft real-time applications. -+ * -+ * BFQ is described in [1], where also a reference to the initial, more -+ * theoretical paper on BFQ can be found. The interested reader can find in -+ * the latter paper full details on the main algorithm as well as formulas of -+ * the guarantees, plus formal proofs of all the properties. With respect to -+ * the version of BFQ presented in these papers, this implementation adds a -+ * few more heuristics, such as the one that guarantees a low latency to soft -+ * real-time applications, and a hierarchical extension based on H-WF2Q+. -+ * -+ * B-WF2Q+ is based on WF2Q+, that is described in [2], together with -+ * H-WF2Q+, while the augmented tree used to implement B-WF2Q+ with O(log N) -+ * complexity derives from the one introduced with EEVDF in [3]. -+ * -+ * [1] P. Valente and M. Andreolini, ``Improving Application Responsiveness -+ * with the BFQ Disk I/O Scheduler'', -+ * Proceedings of the 5th Annual International Systems and Storage -+ * Conference (SYSTOR '12), June 2012. -+ * -+ * http://algogroup.unimo.it/people/paolo/disk_sched/bf1-v1-suite-results.pdf -+ * -+ * [2] Jon C.R. Bennett and H. Zhang, ``Hierarchical Packet Fair Queueing -+ * Algorithms,'' IEEE/ACM Transactions on Networking, 5(5):675-689, -+ * Oct 1997. -+ * -+ * http://www.cs.cmu.edu/~hzhang/papers/TON-97-Oct.ps.gz -+ * -+ * [3] I. Stoica and H. Abdel-Wahab, ``Earliest Eligible Virtual Deadline -+ * First: A Flexible and Accurate Mechanism for Proportional Share -+ * Resource Allocation,'' technical report. -+ * -+ * http://www.cs.berkeley.edu/~istoica/papers/eevdf-tr-95.pdf -+ */ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include "bfq.h" -+#include "blk.h" -+ -+/* Max number of dispatches in one round of service. */ -+static const int bfq_quantum = 4; -+ -+/* Expiration time of sync (0) and async (1) requests, in jiffies. */ -+static const int bfq_fifo_expire[2] = { HZ / 4, HZ / 8 }; -+ -+/* Maximum backwards seek, in KiB. */ -+static const int bfq_back_max = 16 * 1024; -+ -+/* Penalty of a backwards seek, in number of sectors. */ -+static const int bfq_back_penalty = 2; -+ -+/* Idling period duration, in jiffies. */ -+static int bfq_slice_idle = HZ / 125; -+ -+/* Default maximum budget values, in sectors and number of requests. */ -+static const int bfq_default_max_budget = 16 * 1024; -+static const int bfq_max_budget_async_rq = 4; -+ -+/* -+ * Async to sync throughput distribution is controlled as follows: -+ * when an async request is served, the entity is charged the number -+ * of sectors of the request, multipled by the factor below -+ */ -+static const int bfq_async_charge_factor = 10; -+ -+/* Default timeout values, in jiffies, approximating CFQ defaults. */ -+static const int bfq_timeout_sync = HZ / 8; -+static int bfq_timeout_async = HZ / 25; -+ -+struct kmem_cache *bfq_pool; -+ -+/* Below this threshold (in ms), we consider thinktime immediate. */ -+#define BFQ_MIN_TT 2 -+ -+/* hw_tag detection: parallel requests threshold and min samples needed. */ -+#define BFQ_HW_QUEUE_THRESHOLD 4 -+#define BFQ_HW_QUEUE_SAMPLES 32 -+ -+#define BFQQ_SEEK_THR (sector_t)(8 * 1024) -+#define BFQQ_SEEKY(bfqq) ((bfqq)->seek_mean > BFQQ_SEEK_THR) -+ -+/* Min samples used for peak rate estimation (for autotuning). */ -+#define BFQ_PEAK_RATE_SAMPLES 32 -+ -+/* Shift used for peak rate fixed precision calculations. */ -+#define BFQ_RATE_SHIFT 16 -+ -+/* -+ * The duration of the weight raising for interactive applications is -+ * computed automatically (as default behaviour), using the following -+ * formula: duration = (R / r) * T, where r is the peak rate of the -+ * disk, and R and T are two reference parameters. In particular, R is -+ * the peak rate of a reference disk, and T is about the maximum time -+ * for starting popular large applications on that disk, under BFQ and -+ * while reading two files in parallel. Finally, BFQ uses two -+ * different pairs (R, T) depending on whether the disk is rotational -+ * or non-rotational. -+ */ -+#define T_rot (msecs_to_jiffies(5500)) -+#define T_nonrot (msecs_to_jiffies(2000)) -+/* Next two quantities are in sectors/usec, left-shifted by BFQ_RATE_SHIFT */ -+#define R_rot 17415 -+#define R_nonrot 34791 -+ -+#define BFQ_SERVICE_TREE_INIT ((struct bfq_service_tree) \ -+ { RB_ROOT, RB_ROOT, NULL, NULL, 0, 0 }) -+ -+#define RQ_BIC(rq) ((struct bfq_io_cq *) (rq)->elv.priv[0]) -+#define RQ_BFQQ(rq) ((rq)->elv.priv[1]) -+ -+static inline void bfq_schedule_dispatch(struct bfq_data *bfqd); -+ -+#include "bfq-ioc.c" -+#include "bfq-sched.c" -+#include "bfq-cgroup.c" -+ -+#define bfq_class_idle(bfqq) ((bfqq)->entity.ioprio_class ==\ -+ IOPRIO_CLASS_IDLE) -+#define bfq_class_rt(bfqq) ((bfqq)->entity.ioprio_class ==\ -+ IOPRIO_CLASS_RT) -+ -+#define bfq_sample_valid(samples) ((samples) > 80) -+ -+/* -+ * We regard a request as SYNC, if either it's a read or has the SYNC bit -+ * set (in which case it could also be a direct WRITE). -+ */ -+static inline int bfq_bio_sync(struct bio *bio) -+{ -+ if (bio_data_dir(bio) == READ || (bio->bi_rw & REQ_SYNC)) -+ return 1; -+ -+ return 0; -+} -+ -+/* -+ * Scheduler run of queue, if there are requests pending and no one in the -+ * driver that will restart queueing. -+ */ -+static inline void bfq_schedule_dispatch(struct bfq_data *bfqd) -+{ -+ if (bfqd->queued != 0) { -+ bfq_log(bfqd, "schedule dispatch"); -+ kblockd_schedule_work(bfqd->queue, &bfqd->unplug_work); -+ } -+} -+ -+/* -+ * Lifted from AS - choose which of rq1 and rq2 that is best served now. -+ * We choose the request that is closesr to the head right now. Distance -+ * behind the head is penalized and only allowed to a certain extent. -+ */ -+static struct request *bfq_choose_req(struct bfq_data *bfqd, -+ struct request *rq1, -+ struct request *rq2, -+ sector_t last) -+{ -+ sector_t s1, s2, d1 = 0, d2 = 0; -+ unsigned long back_max; -+#define BFQ_RQ1_WRAP 0x01 /* request 1 wraps */ -+#define BFQ_RQ2_WRAP 0x02 /* request 2 wraps */ -+ unsigned wrap = 0; /* bit mask: requests behind the disk head? */ -+ -+ if (rq1 == NULL || rq1 == rq2) -+ return rq2; -+ if (rq2 == NULL) -+ return rq1; -+ -+ if (rq_is_sync(rq1) && !rq_is_sync(rq2)) -+ return rq1; -+ else if (rq_is_sync(rq2) && !rq_is_sync(rq1)) -+ return rq2; -+ if ((rq1->cmd_flags & REQ_META) && !(rq2->cmd_flags & REQ_META)) -+ return rq1; -+ else if ((rq2->cmd_flags & REQ_META) && !(rq1->cmd_flags & REQ_META)) -+ return rq2; -+ -+ s1 = blk_rq_pos(rq1); -+ s2 = blk_rq_pos(rq2); -+ -+ /* -+ * By definition, 1KiB is 2 sectors. -+ */ -+ back_max = bfqd->bfq_back_max * 2; -+ -+ /* -+ * Strict one way elevator _except_ in the case where we allow -+ * short backward seeks which are biased as twice the cost of a -+ * similar forward seek. -+ */ -+ if (s1 >= last) -+ d1 = s1 - last; -+ else if (s1 + back_max >= last) -+ d1 = (last - s1) * bfqd->bfq_back_penalty; -+ else -+ wrap |= BFQ_RQ1_WRAP; -+ -+ if (s2 >= last) -+ d2 = s2 - last; -+ else if (s2 + back_max >= last) -+ d2 = (last - s2) * bfqd->bfq_back_penalty; -+ else -+ wrap |= BFQ_RQ2_WRAP; -+ -+ /* Found required data */ -+ -+ /* -+ * By doing switch() on the bit mask "wrap" we avoid having to -+ * check two variables for all permutations: --> faster! -+ */ -+ switch (wrap) { -+ case 0: /* common case for CFQ: rq1 and rq2 not wrapped */ -+ if (d1 < d2) -+ return rq1; -+ else if (d2 < d1) -+ return rq2; -+ else { -+ if (s1 >= s2) -+ return rq1; -+ else -+ return rq2; -+ } -+ -+ case BFQ_RQ2_WRAP: -+ return rq1; -+ case BFQ_RQ1_WRAP: -+ return rq2; -+ case (BFQ_RQ1_WRAP|BFQ_RQ2_WRAP): /* both rqs wrapped */ -+ default: -+ /* -+ * Since both rqs are wrapped, -+ * start with the one that's further behind head -+ * (--> only *one* back seek required), -+ * since back seek takes more time than forward. -+ */ -+ if (s1 <= s2) -+ return rq1; -+ else -+ return rq2; -+ } -+} -+ -+static struct bfq_queue * -+bfq_rq_pos_tree_lookup(struct bfq_data *bfqd, struct rb_root *root, -+ sector_t sector, struct rb_node **ret_parent, -+ struct rb_node ***rb_link) -+{ -+ struct rb_node **p, *parent; -+ struct bfq_queue *bfqq = NULL; -+ -+ parent = NULL; -+ p = &root->rb_node; -+ while (*p) { -+ struct rb_node **n; -+ -+ parent = *p; -+ bfqq = rb_entry(parent, struct bfq_queue, pos_node); -+ -+ /* -+ * Sort strictly based on sector. Smallest to the left, -+ * largest to the right. -+ */ -+ if (sector > blk_rq_pos(bfqq->next_rq)) -+ n = &(*p)->rb_right; -+ else if (sector < blk_rq_pos(bfqq->next_rq)) -+ n = &(*p)->rb_left; -+ else -+ break; -+ p = n; -+ bfqq = NULL; -+ } -+ -+ *ret_parent = parent; -+ if (rb_link) -+ *rb_link = p; -+ -+ bfq_log(bfqd, "rq_pos_tree_lookup %llu: returning %d", -+ (long long unsigned)sector, -+ bfqq != NULL ? bfqq->pid : 0); -+ -+ return bfqq; -+} -+ -+static void bfq_rq_pos_tree_add(struct bfq_data *bfqd, struct bfq_queue *bfqq) -+{ -+ struct rb_node **p, *parent; -+ struct bfq_queue *__bfqq; -+ -+ if (bfqq->pos_root != NULL) { -+ rb_erase(&bfqq->pos_node, bfqq->pos_root); -+ bfqq->pos_root = NULL; -+ } -+ -+ if (bfq_class_idle(bfqq)) -+ return; -+ if (!bfqq->next_rq) -+ return; -+ -+ bfqq->pos_root = &bfqd->rq_pos_tree; -+ __bfqq = bfq_rq_pos_tree_lookup(bfqd, bfqq->pos_root, -+ blk_rq_pos(bfqq->next_rq), &parent, &p); -+ if (__bfqq == NULL) { -+ rb_link_node(&bfqq->pos_node, parent, p); -+ rb_insert_color(&bfqq->pos_node, bfqq->pos_root); -+ } else -+ bfqq->pos_root = NULL; -+} -+ -+static struct request *bfq_find_next_rq(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq, -+ struct request *last) -+{ -+ struct rb_node *rbnext = rb_next(&last->rb_node); -+ struct rb_node *rbprev = rb_prev(&last->rb_node); -+ struct request *next = NULL, *prev = NULL; -+ -+ BUG_ON(RB_EMPTY_NODE(&last->rb_node)); -+ -+ if (rbprev != NULL) -+ prev = rb_entry_rq(rbprev); -+ -+ if (rbnext != NULL) -+ next = rb_entry_rq(rbnext); -+ else { -+ rbnext = rb_first(&bfqq->sort_list); -+ if (rbnext && rbnext != &last->rb_node) -+ next = rb_entry_rq(rbnext); -+ } -+ -+ return bfq_choose_req(bfqd, next, prev, blk_rq_pos(last)); -+} -+ -+static void bfq_del_rq_rb(struct request *rq) -+{ -+ struct bfq_queue *bfqq = RQ_BFQQ(rq); -+ struct bfq_data *bfqd = bfqq->bfqd; -+ const int sync = rq_is_sync(rq); -+ -+ BUG_ON(bfqq->queued[sync] == 0); -+ bfqq->queued[sync]--; -+ bfqd->queued--; -+ -+ elv_rb_del(&bfqq->sort_list, rq); -+ -+ if (RB_EMPTY_ROOT(&bfqq->sort_list)) { -+ if (bfq_bfqq_busy(bfqq) && bfqq != bfqd->in_service_queue) -+ bfq_del_bfqq_busy(bfqd, bfqq, 1); -+ /* -+ * Remove queue from request-position tree as it is empty. -+ */ -+ if (bfqq->pos_root != NULL) { -+ rb_erase(&bfqq->pos_node, bfqq->pos_root); -+ bfqq->pos_root = NULL; -+ } -+ } -+} -+ -+/* see the definition of bfq_async_charge_factor for details */ -+static inline unsigned long bfq_serv_to_charge(struct request *rq, -+ struct bfq_queue *bfqq) -+{ -+ return blk_rq_sectors(rq) * -+ (1 + ((!bfq_bfqq_sync(bfqq)) * (bfqq->raising_coeff == 1) * -+ bfq_async_charge_factor)); -+} -+ -+/** -+ * bfq_updated_next_req - update the queue after a new next_rq selection. -+ * @bfqd: the device data the queue belongs to. -+ * @bfqq: the queue to update. -+ * -+ * If the first request of a queue changes we make sure that the queue -+ * has enough budget to serve at least its first request (if the -+ * request has grown). We do this because if the queue has not enough -+ * budget for its first request, it has to go through two dispatch -+ * rounds to actually get it dispatched. -+ */ -+static void bfq_updated_next_req(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq) -+{ -+ struct bfq_entity *entity = &bfqq->entity; -+ struct bfq_service_tree *st = bfq_entity_service_tree(entity); -+ struct request *next_rq = bfqq->next_rq; -+ unsigned long new_budget; -+ -+ if (next_rq == NULL) -+ return; -+ -+ if (bfqq == bfqd->in_service_queue) -+ /* -+ * In order not to break guarantees, budgets cannot be -+ * changed after an entity has been selected. -+ */ -+ return; -+ -+ BUG_ON(entity->tree != &st->active); -+ BUG_ON(entity == entity->sched_data->active_entity); -+ -+ new_budget = max_t(unsigned long, bfqq->max_budget, -+ bfq_serv_to_charge(next_rq, bfqq)); -+ entity->budget = new_budget; -+ bfq_log_bfqq(bfqd, bfqq, "updated next rq: new budget %lu", new_budget); -+ bfq_activate_bfqq(bfqd, bfqq); -+} -+ -+static inline unsigned int bfq_wrais_duration(struct bfq_data *bfqd) -+{ -+ u64 dur; -+ -+ if (bfqd->bfq_raising_max_time > 0) -+ return bfqd->bfq_raising_max_time; -+ -+ dur = bfqd->RT_prod; -+ do_div(dur, bfqd->peak_rate); -+ -+ return dur; -+} -+ -+static void bfq_add_rq_rb(struct request *rq) -+{ -+ struct bfq_queue *bfqq = RQ_BFQQ(rq); -+ struct bfq_entity *entity = &bfqq->entity; -+ struct bfq_data *bfqd = bfqq->bfqd; -+ struct request *next_rq, *prev; -+ unsigned long old_raising_coeff = bfqq->raising_coeff; -+ int idle_for_long_time = 0; -+ -+ bfq_log_bfqq(bfqd, bfqq, "add_rq_rb %d", rq_is_sync(rq)); -+ bfqq->queued[rq_is_sync(rq)]++; -+ bfqd->queued++; -+ -+ elv_rb_add(&bfqq->sort_list, rq); -+ -+ /* -+ * Check if this request is a better next-serve candidate. -+ */ -+ prev = bfqq->next_rq; -+ next_rq = bfq_choose_req(bfqd, bfqq->next_rq, rq, bfqd->last_position); -+ BUG_ON(next_rq == NULL); -+ bfqq->next_rq = next_rq; -+ -+ /* -+ * Adjust priority tree position, if next_rq changes. -+ */ -+ if (prev != bfqq->next_rq) -+ bfq_rq_pos_tree_add(bfqd, bfqq); -+ -+ if (!bfq_bfqq_busy(bfqq)) { -+ int soft_rt = bfqd->bfq_raising_max_softrt_rate > 0 && -+ time_is_before_jiffies(bfqq->soft_rt_next_start); -+ idle_for_long_time = time_is_before_jiffies( -+ bfqq->budget_timeout + -+ bfqd->bfq_raising_min_idle_time); -+ entity->budget = max_t(unsigned long, bfqq->max_budget, -+ bfq_serv_to_charge(next_rq, bfqq)); -+ -+ if (!bfqd->low_latency) -+ goto add_bfqq_busy; -+ -+ /* -+ * If the queue is not being boosted and has been idle -+ * for enough time, start a weight-raising period -+ */ -+ if (old_raising_coeff == 1 && -+ (idle_for_long_time || soft_rt)) { -+ bfqq->raising_coeff = bfqd->bfq_raising_coeff; -+ if (idle_for_long_time) -+ bfqq->raising_cur_max_time = -+ bfq_wrais_duration(bfqd); -+ else -+ bfqq->raising_cur_max_time = -+ bfqd->bfq_raising_rt_max_time; -+ bfq_log_bfqq(bfqd, bfqq, -+ "wrais starting at %llu msec," -+ "rais_max_time %u", -+ bfqq->last_rais_start_finish, -+ jiffies_to_msecs(bfqq-> -+ raising_cur_max_time)); -+ } else if (old_raising_coeff > 1) { -+ if (idle_for_long_time) -+ bfqq->raising_cur_max_time = -+ bfq_wrais_duration(bfqd); -+ else if (bfqq->raising_cur_max_time == -+ bfqd->bfq_raising_rt_max_time && -+ !soft_rt) { -+ bfqq->raising_coeff = 1; -+ bfq_log_bfqq(bfqd, bfqq, -+ "wrais ending at %llu msec," -+ "rais_max_time %u", -+ bfqq->last_rais_start_finish, -+ jiffies_to_msecs(bfqq-> -+ raising_cur_max_time)); -+ } else if ((bfqq->last_rais_start_finish + -+ bfqq->raising_cur_max_time < -+ jiffies + bfqd->bfq_raising_rt_max_time) && -+ soft_rt) { -+ /* -+ * -+ * The remaining weight-raising time is lower -+ * than bfqd->bfq_raising_rt_max_time, which -+ * means that the application is enjoying -+ * weight raising either because deemed soft rt -+ * in the near past, or because deemed -+ * interactive a long ago. In both cases, -+ * resetting now the current remaining weight- -+ * raising time for the application to the -+ * weight-raising duration for soft rt -+ * applications would not cause any latency -+ * increase for the application (as the new -+ * duration would be higher than the remaining -+ * time). -+ * -+ * In addition, the application is now meeting -+ * the requirements for being deemed soft rt. -+ * In the end we can correctly and safely -+ * (re)charge the weight-raising duration for -+ * the application with the weight-raising -+ * duration for soft rt applications. -+ * -+ * In particular, doing this recharge now, i.e., -+ * before the weight-raising period for the -+ * application finishes, reduces the probability -+ * of the following negative scenario: -+ * 1) the weight of a soft rt application is -+ * raised at startup (as for any newly -+ * created application), -+ * 2) since the application is not interactive, -+ * at a certain time weight-raising is -+ * stopped for the application, -+ * 3) at that time the application happens to -+ * still have pending requests, and hence -+ * is destined to not have a chance to be -+ * deemed soft rt before these requests are -+ * completed (see the comments to the -+ * function bfq_bfqq_softrt_next_start() -+ * for details on soft rt detection), -+ * 4) these pending requests experience a high -+ * latency because the application is not -+ * weight-raised while they are pending. -+ */ -+ bfqq->last_rais_start_finish = jiffies; -+ bfqq->raising_cur_max_time = -+ bfqd->bfq_raising_rt_max_time; -+ } -+ } -+ if (old_raising_coeff != bfqq->raising_coeff) -+ entity->ioprio_changed = 1; -+add_bfqq_busy: -+ bfqq->last_idle_bklogged = jiffies; -+ bfqq->service_from_backlogged = 0; -+ bfq_clear_bfqq_softrt_update(bfqq); -+ bfq_add_bfqq_busy(bfqd, bfqq); -+ } else { -+ if (bfqd->low_latency && old_raising_coeff == 1 && -+ !rq_is_sync(rq) && -+ bfqq->last_rais_start_finish + -+ time_is_before_jiffies( -+ bfqd->bfq_raising_min_inter_arr_async)) { -+ bfqq->raising_coeff = bfqd->bfq_raising_coeff; -+ bfqq->raising_cur_max_time = bfq_wrais_duration(bfqd); -+ -+ bfqd->raised_busy_queues++; -+ entity->ioprio_changed = 1; -+ bfq_log_bfqq(bfqd, bfqq, -+ "non-idle wrais starting at %llu msec," -+ "rais_max_time %u", -+ bfqq->last_rais_start_finish, -+ jiffies_to_msecs(bfqq-> -+ raising_cur_max_time)); -+ } -+ bfq_updated_next_req(bfqd, bfqq); -+ } -+ -+ if (bfqd->low_latency && -+ (old_raising_coeff == 1 || bfqq->raising_coeff == 1 || -+ idle_for_long_time)) -+ bfqq->last_rais_start_finish = jiffies; -+} -+ -+static void bfq_reposition_rq_rb(struct bfq_queue *bfqq, struct request *rq) -+{ -+ elv_rb_del(&bfqq->sort_list, rq); -+ bfqq->queued[rq_is_sync(rq)]--; -+ bfqq->bfqd->queued--; -+ bfq_add_rq_rb(rq); -+} -+ -+static struct request *bfq_find_rq_fmerge(struct bfq_data *bfqd, -+ struct bio *bio) -+{ -+ struct task_struct *tsk = current; -+ struct bfq_io_cq *bic; -+ struct bfq_queue *bfqq; -+ -+ bic = bfq_bic_lookup(bfqd, tsk->io_context); -+ if (bic == NULL) -+ return NULL; -+ -+ bfqq = bic_to_bfqq(bic, bfq_bio_sync(bio)); -+ if (bfqq != NULL) -+ return elv_rb_find(&bfqq->sort_list, bio_end_sector(bio)); -+ -+ return NULL; -+} -+ -+static void bfq_activate_request(struct request_queue *q, struct request *rq) -+{ -+ struct bfq_data *bfqd = q->elevator->elevator_data; -+ -+ bfqd->rq_in_driver++; -+ bfqd->last_position = blk_rq_pos(rq) + blk_rq_sectors(rq); -+ bfq_log(bfqd, "activate_request: new bfqd->last_position %llu", -+ (long long unsigned)bfqd->last_position); -+} -+ -+static void bfq_deactivate_request(struct request_queue *q, struct request *rq) -+{ -+ struct bfq_data *bfqd = q->elevator->elevator_data; -+ -+ WARN_ON(bfqd->rq_in_driver == 0); -+ bfqd->rq_in_driver--; -+} -+ -+static void bfq_remove_request(struct request *rq) -+{ -+ struct bfq_queue *bfqq = RQ_BFQQ(rq); -+ struct bfq_data *bfqd = bfqq->bfqd; -+ -+ if (bfqq->next_rq == rq) { -+ bfqq->next_rq = bfq_find_next_rq(bfqd, bfqq, rq); -+ bfq_updated_next_req(bfqd, bfqq); -+ } -+ -+ list_del_init(&rq->queuelist); -+ bfq_del_rq_rb(rq); -+ -+ if (rq->cmd_flags & REQ_META) { -+ WARN_ON(bfqq->meta_pending == 0); -+ bfqq->meta_pending--; -+ } -+} -+ -+static int bfq_merge(struct request_queue *q, struct request **req, -+ struct bio *bio) -+{ -+ struct bfq_data *bfqd = q->elevator->elevator_data; -+ struct request *__rq; -+ -+ __rq = bfq_find_rq_fmerge(bfqd, bio); -+ if (__rq != NULL && elv_rq_merge_ok(__rq, bio)) { -+ *req = __rq; -+ return ELEVATOR_FRONT_MERGE; -+ } -+ -+ return ELEVATOR_NO_MERGE; -+} -+ -+static void bfq_merged_request(struct request_queue *q, struct request *req, -+ int type) -+{ -+ if (type == ELEVATOR_FRONT_MERGE) { -+ struct bfq_queue *bfqq = RQ_BFQQ(req); -+ -+ bfq_reposition_rq_rb(bfqq, req); -+ } -+} -+ -+static void bfq_merged_requests(struct request_queue *q, struct request *rq, -+ struct request *next) -+{ -+ struct bfq_queue *bfqq = RQ_BFQQ(rq); -+ -+ /* -+ * Reposition in fifo if next is older than rq. -+ */ -+ if (!list_empty(&rq->queuelist) && !list_empty(&next->queuelist) && -+ time_before(rq_fifo_time(next), rq_fifo_time(rq))) { -+ list_move(&rq->queuelist, &next->queuelist); -+ rq_set_fifo_time(rq, rq_fifo_time(next)); -+ } -+ -+ if (bfqq->next_rq == next) -+ bfqq->next_rq = rq; -+ -+ bfq_remove_request(next); -+} -+ -+/* Must be called with bfqq != NULL */ -+static inline void bfq_bfqq_end_raising(struct bfq_queue *bfqq) -+{ -+ BUG_ON(bfqq == NULL); -+ if (bfq_bfqq_busy(bfqq)) -+ bfqq->bfqd->raised_busy_queues--; -+ bfqq->raising_coeff = 1; -+ bfqq->raising_cur_max_time = 0; -+ /* Trigger a weight change on the next activation of the queue */ -+ bfqq->entity.ioprio_changed = 1; -+} -+ -+static void bfq_end_raising_async_queues(struct bfq_data *bfqd, -+ struct bfq_group *bfqg) -+{ -+ int i, j; -+ -+ for (i = 0; i < 2; i++) -+ for (j = 0; j < IOPRIO_BE_NR; j++) -+ if (bfqg->async_bfqq[i][j] != NULL) -+ bfq_bfqq_end_raising(bfqg->async_bfqq[i][j]); -+ if (bfqg->async_idle_bfqq != NULL) -+ bfq_bfqq_end_raising(bfqg->async_idle_bfqq); -+} -+ -+static void bfq_end_raising(struct bfq_data *bfqd) -+{ -+ struct bfq_queue *bfqq; -+ -+ spin_lock_irq(bfqd->queue->queue_lock); -+ -+ list_for_each_entry(bfqq, &bfqd->active_list, bfqq_list) -+ bfq_bfqq_end_raising(bfqq); -+ list_for_each_entry(bfqq, &bfqd->idle_list, bfqq_list) -+ bfq_bfqq_end_raising(bfqq); -+ bfq_end_raising_async(bfqd); -+ -+ spin_unlock_irq(bfqd->queue->queue_lock); -+} -+ -+static int bfq_allow_merge(struct request_queue *q, struct request *rq, -+ struct bio *bio) -+{ -+ struct bfq_data *bfqd = q->elevator->elevator_data; -+ struct bfq_io_cq *bic; -+ struct bfq_queue *bfqq; -+ -+ /* -+ * Disallow merge of a sync bio into an async request. -+ */ -+ if (bfq_bio_sync(bio) && !rq_is_sync(rq)) -+ return 0; -+ -+ /* -+ * Lookup the bfqq that this bio will be queued with. Allow -+ * merge only if rq is queued there. -+ * Queue lock is held here. -+ */ -+ bic = bfq_bic_lookup(bfqd, current->io_context); -+ if (bic == NULL) -+ return 0; -+ -+ bfqq = bic_to_bfqq(bic, bfq_bio_sync(bio)); -+ return bfqq == RQ_BFQQ(rq); -+} -+ -+static void __bfq_set_in_service_queue(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq) -+{ -+ if (bfqq != NULL) { -+ bfq_mark_bfqq_must_alloc(bfqq); -+ bfq_mark_bfqq_budget_new(bfqq); -+ bfq_clear_bfqq_fifo_expire(bfqq); -+ -+ bfqd->budgets_assigned = (bfqd->budgets_assigned*7 + 256) / 8; -+ -+ bfq_log_bfqq(bfqd, bfqq, -+ "set_in_service_queue, cur-budget = %lu", -+ bfqq->entity.budget); -+ } -+ -+ bfqd->in_service_queue = bfqq; -+} -+ -+/* -+ * Get and set a new queue for service. -+ */ -+static struct bfq_queue *bfq_set_in_service_queue(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq) -+{ -+ if (!bfqq) -+ bfqq = bfq_get_next_queue(bfqd); -+ else -+ bfq_get_next_queue_forced(bfqd, bfqq); -+ -+ __bfq_set_in_service_queue(bfqd, bfqq); -+ return bfqq; -+} -+ -+static inline sector_t bfq_dist_from_last(struct bfq_data *bfqd, -+ struct request *rq) -+{ -+ if (blk_rq_pos(rq) >= bfqd->last_position) -+ return blk_rq_pos(rq) - bfqd->last_position; -+ else -+ return bfqd->last_position - blk_rq_pos(rq); -+} -+ -+/* -+ * Return true if bfqq has no request pending and rq is close enough to -+ * bfqd->last_position, or if rq is closer to bfqd->last_position than -+ * bfqq->next_rq -+ */ -+static inline int bfq_rq_close(struct bfq_data *bfqd, struct request *rq) -+{ -+ return bfq_dist_from_last(bfqd, rq) <= BFQQ_SEEK_THR; -+} -+ -+static struct bfq_queue *bfqq_close(struct bfq_data *bfqd) -+{ -+ struct rb_root *root = &bfqd->rq_pos_tree; -+ struct rb_node *parent, *node; -+ struct bfq_queue *__bfqq; -+ sector_t sector = bfqd->last_position; -+ -+ if (RB_EMPTY_ROOT(root)) -+ return NULL; -+ -+ /* -+ * First, if we find a request starting at the end of the last -+ * request, choose it. -+ */ -+ __bfqq = bfq_rq_pos_tree_lookup(bfqd, root, sector, &parent, NULL); -+ if (__bfqq != NULL) -+ return __bfqq; -+ -+ /* -+ * If the exact sector wasn't found, the parent of the NULL leaf -+ * will contain the closest sector (rq_pos_tree sorted by next_request -+ * position). -+ */ -+ __bfqq = rb_entry(parent, struct bfq_queue, pos_node); -+ if (bfq_rq_close(bfqd, __bfqq->next_rq)) -+ return __bfqq; -+ -+ if (blk_rq_pos(__bfqq->next_rq) < sector) -+ node = rb_next(&__bfqq->pos_node); -+ else -+ node = rb_prev(&__bfqq->pos_node); -+ if (node == NULL) -+ return NULL; -+ -+ __bfqq = rb_entry(node, struct bfq_queue, pos_node); -+ if (bfq_rq_close(bfqd, __bfqq->next_rq)) -+ return __bfqq; -+ -+ return NULL; -+} -+ -+/* -+ * bfqd - obvious -+ * cur_bfqq - passed in so that we don't decide that the current queue -+ * is closely cooperating with itself. -+ * -+ * We are assuming that cur_bfqq has dispatched at least one request, -+ * and that bfqd->last_position reflects a position on the disk associated -+ * with the I/O issued by cur_bfqq. -+ */ -+static struct bfq_queue *bfq_close_cooperator(struct bfq_data *bfqd, -+ struct bfq_queue *cur_bfqq) -+{ -+ struct bfq_queue *bfqq; -+ -+ if (bfq_class_idle(cur_bfqq)) -+ return NULL; -+ if (!bfq_bfqq_sync(cur_bfqq)) -+ return NULL; -+ if (BFQQ_SEEKY(cur_bfqq)) -+ return NULL; -+ -+ /* If device has only one backlogged bfq_queue, don't search. */ -+ if (bfqd->busy_queues == 1) -+ return NULL; -+ -+ /* -+ * We should notice if some of the queues are cooperating, e.g. -+ * working closely on the same area of the disk. In that case, -+ * we can group them together and don't waste time idling. -+ */ -+ bfqq = bfqq_close(bfqd); -+ if (bfqq == NULL || bfqq == cur_bfqq) -+ return NULL; -+ -+ /* -+ * Do not merge queues from different bfq_groups. -+ */ -+ if (bfqq->entity.parent != cur_bfqq->entity.parent) -+ return NULL; -+ -+ /* -+ * It only makes sense to merge sync queues. -+ */ -+ if (!bfq_bfqq_sync(bfqq)) -+ return NULL; -+ if (BFQQ_SEEKY(bfqq)) -+ return NULL; -+ -+ /* -+ * Do not merge queues of different priority classes. -+ */ -+ if (bfq_class_rt(bfqq) != bfq_class_rt(cur_bfqq)) -+ return NULL; -+ -+ return bfqq; -+} -+ -+/* -+ * If enough samples have been computed, return the current max budget -+ * stored in bfqd, which is dynamically updated according to the -+ * estimated disk peak rate; otherwise return the default max budget -+ */ -+static inline unsigned long bfq_max_budget(struct bfq_data *bfqd) -+{ -+ if (bfqd->budgets_assigned < 194) -+ return bfq_default_max_budget; -+ else -+ return bfqd->bfq_max_budget; -+} -+ -+/* -+ * Return min budget, which is a fraction of the current or default -+ * max budget (trying with 1/32) -+ */ -+static inline unsigned long bfq_min_budget(struct bfq_data *bfqd) -+{ -+ if (bfqd->budgets_assigned < 194) -+ return bfq_default_max_budget / 32; -+ else -+ return bfqd->bfq_max_budget / 32; -+} -+ -+/* -+ * Decides whether idling should be done for given device and -+ * given in-service queue. -+ */ -+static inline bool bfq_queue_nonrot_noidle(struct bfq_data *bfqd, -+ struct bfq_queue *in_service_bfqq) -+{ -+ if (in_service_bfqq == NULL) -+ return false; -+ /* -+ * If device is SSD it has no seek penalty, disable idling; but -+ * do so only if: -+ * - device does not support queuing, otherwise we still have -+ * a problem with sync vs async workloads; -+ * - the queue is not weight-raised, to preserve guarantees. -+ */ -+ return (blk_queue_nonrot(bfqd->queue) && bfqd->hw_tag && -+ in_service_bfqq->raising_coeff == 1); -+} -+ -+static void bfq_arm_slice_timer(struct bfq_data *bfqd) -+{ -+ struct bfq_queue *bfqq = bfqd->in_service_queue; -+ struct bfq_io_cq *bic; -+ unsigned long sl; -+ -+ WARN_ON(!RB_EMPTY_ROOT(&bfqq->sort_list)); -+ -+ /* Tasks have exited, don't wait. */ -+ bic = bfqd->in_service_bic; -+ if (bic == NULL || atomic_read(&bic->icq.ioc->active_ref) == 0) -+ return; -+ -+ bfq_mark_bfqq_wait_request(bfqq); -+ -+ /* -+ * We don't want to idle for seeks, but we do want to allow -+ * fair distribution of slice time for a process doing back-to-back -+ * seeks. So allow a little bit of time for him to submit a new rq. -+ * -+ * To prevent processes with (partly) seeky workloads from -+ * being too ill-treated, grant them a small fraction of the -+ * assigned budget before reducing the waiting time to -+ * BFQ_MIN_TT. This happened to help reduce latency. -+ */ -+ sl = bfqd->bfq_slice_idle; -+ if (bfq_sample_valid(bfqq->seek_samples) && BFQQ_SEEKY(bfqq) && -+ bfqq->entity.service > bfq_max_budget(bfqd) / 8 && -+ bfqq->raising_coeff == 1) -+ sl = min(sl, msecs_to_jiffies(BFQ_MIN_TT)); -+ else if (bfqq->raising_coeff > 1) -+ sl = sl * 3; -+ bfqd->last_idling_start = ktime_get(); -+ mod_timer(&bfqd->idle_slice_timer, jiffies + sl); -+ bfq_log(bfqd, "arm idle: %u/%u ms", -+ jiffies_to_msecs(sl), jiffies_to_msecs(bfqd->bfq_slice_idle)); -+} -+ -+/* -+ * Set the maximum time for the in-service queue to consume its -+ * budget. This prevents seeky processes from lowering the disk -+ * throughput (always guaranteed with a time slice scheme as in CFQ). -+ */ -+static void bfq_set_budget_timeout(struct bfq_data *bfqd) -+{ -+ struct bfq_queue *bfqq = bfqd->in_service_queue; -+ unsigned int timeout_coeff; -+ if (bfqq->raising_cur_max_time == bfqd->bfq_raising_rt_max_time) -+ timeout_coeff = 1; -+ else -+ timeout_coeff = bfqq->entity.weight / bfqq->entity.orig_weight; -+ -+ bfqd->last_budget_start = ktime_get(); -+ -+ bfq_clear_bfqq_budget_new(bfqq); -+ bfqq->budget_timeout = jiffies + -+ bfqd->bfq_timeout[bfq_bfqq_sync(bfqq)] * timeout_coeff; -+ -+ bfq_log_bfqq(bfqd, bfqq, "set budget_timeout %u", -+ jiffies_to_msecs(bfqd->bfq_timeout[bfq_bfqq_sync(bfqq)] * -+ timeout_coeff)); -+} -+ -+/* -+ * Move request from internal lists to the request queue dispatch list. -+ */ -+static void bfq_dispatch_insert(struct request_queue *q, struct request *rq) -+{ -+ struct bfq_data *bfqd = q->elevator->elevator_data; -+ struct bfq_queue *bfqq = RQ_BFQQ(rq); -+ -+ bfq_remove_request(rq); -+ bfqq->dispatched++; -+ elv_dispatch_sort(q, rq); -+ -+ if (bfq_bfqq_sync(bfqq)) -+ bfqd->sync_flight++; -+} -+ -+/* -+ * Return expired entry, or NULL to just start from scratch in rbtree. -+ */ -+static struct request *bfq_check_fifo(struct bfq_queue *bfqq) -+{ -+ struct request *rq = NULL; -+ -+ if (bfq_bfqq_fifo_expire(bfqq)) -+ return NULL; -+ -+ bfq_mark_bfqq_fifo_expire(bfqq); -+ -+ if (list_empty(&bfqq->fifo)) -+ return NULL; -+ -+ rq = rq_entry_fifo(bfqq->fifo.next); -+ -+ if (time_before(jiffies, rq_fifo_time(rq))) -+ return NULL; -+ -+ return rq; -+} -+ -+/* -+ * Must be called with the queue_lock held. -+ */ -+static int bfqq_process_refs(struct bfq_queue *bfqq) -+{ -+ int process_refs, io_refs; -+ -+ io_refs = bfqq->allocated[READ] + bfqq->allocated[WRITE]; -+ process_refs = atomic_read(&bfqq->ref) - io_refs - bfqq->entity.on_st; -+ BUG_ON(process_refs < 0); -+ return process_refs; -+} -+ -+static void bfq_setup_merge(struct bfq_queue *bfqq, struct bfq_queue *new_bfqq) -+{ -+ int process_refs, new_process_refs; -+ struct bfq_queue *__bfqq; -+ -+ /* -+ * If there are no process references on the new_bfqq, then it is -+ * unsafe to follow the ->new_bfqq chain as other bfqq's in the chain -+ * may have dropped their last reference (not just their last process -+ * reference). -+ */ -+ if (!bfqq_process_refs(new_bfqq)) -+ return; -+ -+ /* Avoid a circular list and skip interim queue merges. */ -+ while ((__bfqq = new_bfqq->new_bfqq)) { -+ if (__bfqq == bfqq) -+ return; -+ new_bfqq = __bfqq; -+ } -+ -+ process_refs = bfqq_process_refs(bfqq); -+ new_process_refs = bfqq_process_refs(new_bfqq); -+ /* -+ * If the process for the bfqq has gone away, there is no -+ * sense in merging the queues. -+ */ -+ if (process_refs == 0 || new_process_refs == 0) -+ return; -+ -+ /* -+ * Merge in the direction of the lesser amount of work. -+ */ -+ if (new_process_refs >= process_refs) { -+ bfqq->new_bfqq = new_bfqq; -+ atomic_add(process_refs, &new_bfqq->ref); -+ } else { -+ new_bfqq->new_bfqq = bfqq; -+ atomic_add(new_process_refs, &bfqq->ref); -+ } -+ bfq_log_bfqq(bfqq->bfqd, bfqq, "scheduling merge with queue %d", -+ new_bfqq->pid); -+} -+ -+static inline unsigned long bfq_bfqq_budget_left(struct bfq_queue *bfqq) -+{ -+ struct bfq_entity *entity = &bfqq->entity; -+ return entity->budget - entity->service; -+} -+ -+static void __bfq_bfqq_expire(struct bfq_data *bfqd, struct bfq_queue *bfqq) -+{ -+ BUG_ON(bfqq != bfqd->in_service_queue); -+ -+ __bfq_bfqd_reset_in_service(bfqd); -+ -+ /* -+ * If this bfqq is shared between multiple processes, check -+ * to make sure that those processes are still issuing I/Os -+ * within the mean seek distance. If not, it may be time to -+ * break the queues apart again. -+ */ -+ if (bfq_bfqq_coop(bfqq) && BFQQ_SEEKY(bfqq)) -+ bfq_mark_bfqq_split_coop(bfqq); -+ -+ if (RB_EMPTY_ROOT(&bfqq->sort_list)) { -+ /* -+ * overloading budget_timeout field to store when -+ * the queue remains with no backlog, used by -+ * the weight-raising mechanism -+ */ -+ bfqq->budget_timeout = jiffies; -+ bfq_del_bfqq_busy(bfqd, bfqq, 1); -+ } else { -+ bfq_activate_bfqq(bfqd, bfqq); -+ /* -+ * Resort priority tree of potential close cooperators. -+ */ -+ bfq_rq_pos_tree_add(bfqd, bfqq); -+ } -+} -+ -+/** -+ * __bfq_bfqq_recalc_budget - try to adapt the budget to the @bfqq behavior. -+ * @bfqd: device data. -+ * @bfqq: queue to update. -+ * @reason: reason for expiration. -+ * -+ * Handle the feedback on @bfqq budget. See the body for detailed -+ * comments. -+ */ -+static void __bfq_bfqq_recalc_budget(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq, -+ enum bfqq_expiration reason) -+{ -+ struct request *next_rq; -+ unsigned long budget, min_budget; -+ -+ budget = bfqq->max_budget; -+ min_budget = bfq_min_budget(bfqd); -+ -+ BUG_ON(bfqq != bfqd->in_service_queue); -+ -+ bfq_log_bfqq(bfqd, bfqq, "recalc_budg: last budg %lu, budg left %lu", -+ bfqq->entity.budget, bfq_bfqq_budget_left(bfqq)); -+ bfq_log_bfqq(bfqd, bfqq, "recalc_budg: last max_budg %lu, min budg %lu", -+ budget, bfq_min_budget(bfqd)); -+ bfq_log_bfqq(bfqd, bfqq, "recalc_budg: sync %d, seeky %d", -+ bfq_bfqq_sync(bfqq), BFQQ_SEEKY(bfqd->in_service_queue)); -+ -+ if (bfq_bfqq_sync(bfqq)) { -+ switch (reason) { -+ /* -+ * Caveat: in all the following cases we trade latency -+ * for throughput. -+ */ -+ case BFQ_BFQQ_TOO_IDLE: -+ /* -+ * This is the only case where we may reduce -+ * the budget: if there is no requets of the -+ * process still waiting for completion, then -+ * we assume (tentatively) that the timer has -+ * expired because the batch of requests of -+ * the process could have been served with a -+ * smaller budget. Hence, betting that -+ * process will behave in the same way when it -+ * becomes backlogged again, we reduce its -+ * next budget. As long as we guess right, -+ * this budget cut reduces the latency -+ * experienced by the process. -+ * -+ * However, if there are still outstanding -+ * requests, then the process may have not yet -+ * issued its next request just because it is -+ * still waiting for the completion of some of -+ * the still oustanding ones. So in this -+ * subcase we do not reduce its budget, on the -+ * contrary we increase it to possibly boost -+ * the throughput, as discussed in the -+ * comments to the BUDGET_TIMEOUT case. -+ */ -+ if (bfqq->dispatched > 0) /* still oustanding reqs */ -+ budget = min(budget * 2, bfqd->bfq_max_budget); -+ else { -+ if (budget > 5 * min_budget) -+ budget -= 4 * min_budget; -+ else -+ budget = min_budget; -+ } -+ break; -+ case BFQ_BFQQ_BUDGET_TIMEOUT: -+ /* -+ * We double the budget here because: 1) it -+ * gives the chance to boost the throughput if -+ * this is not a seeky process (which may have -+ * bumped into this timeout because of, e.g., -+ * ZBR), 2) together with charge_full_budget -+ * it helps give seeky processes higher -+ * timestamps, and hence be served less -+ * frequently. -+ */ -+ budget = min(budget * 2, bfqd->bfq_max_budget); -+ break; -+ case BFQ_BFQQ_BUDGET_EXHAUSTED: -+ /* -+ * The process still has backlog, and did not -+ * let either the budget timeout or the disk -+ * idling timeout expire. Hence it is not -+ * seeky, has a short thinktime and may be -+ * happy with a higher budget too. So -+ * definitely increase the budget of this good -+ * candidate to boost the disk throughput. -+ */ -+ budget = min(budget * 4, bfqd->bfq_max_budget); -+ break; -+ case BFQ_BFQQ_NO_MORE_REQUESTS: -+ /* -+ * Leave the budget unchanged. -+ */ -+ default: -+ return; -+ } -+ } else /* async queue */ -+ /* async queues get always the maximum possible budget -+ * (their ability to dispatch is limited by -+ * @bfqd->bfq_max_budget_async_rq). -+ */ -+ budget = bfqd->bfq_max_budget; -+ -+ bfqq->max_budget = budget; -+ -+ if (bfqd->budgets_assigned >= 194 && bfqd->bfq_user_max_budget == 0 && -+ bfqq->max_budget > bfqd->bfq_max_budget) -+ bfqq->max_budget = bfqd->bfq_max_budget; -+ -+ /* -+ * Make sure that we have enough budget for the next request. -+ * Since the finish time of the bfqq must be kept in sync with -+ * the budget, be sure to call __bfq_bfqq_expire() after the -+ * update. -+ */ -+ next_rq = bfqq->next_rq; -+ if (next_rq != NULL) -+ bfqq->entity.budget = max_t(unsigned long, bfqq->max_budget, -+ bfq_serv_to_charge(next_rq, bfqq)); -+ else -+ bfqq->entity.budget = bfqq->max_budget; -+ -+ bfq_log_bfqq(bfqd, bfqq, "head sect: %u, new budget %lu", -+ next_rq != NULL ? blk_rq_sectors(next_rq) : 0, -+ bfqq->entity.budget); -+} -+ -+static unsigned long bfq_calc_max_budget(u64 peak_rate, u64 timeout) -+{ -+ unsigned long max_budget; -+ -+ /* -+ * The max_budget calculated when autotuning is equal to the -+ * amount of sectors transfered in timeout_sync at the -+ * estimated peak rate. -+ */ -+ max_budget = (unsigned long)(peak_rate * 1000 * -+ timeout >> BFQ_RATE_SHIFT); -+ -+ return max_budget; -+} -+ -+/* -+ * In addition to updating the peak rate, checks whether the process -+ * is "slow", and returns 1 if so. This slow flag is used, in addition -+ * to the budget timeout, to reduce the amount of service provided to -+ * seeky processes, and hence reduce their chances to lower the -+ * throughput. See the code for more details. -+ */ -+static int bfq_update_peak_rate(struct bfq_data *bfqd, struct bfq_queue *bfqq, -+ int compensate, enum bfqq_expiration reason) -+{ -+ u64 bw, usecs, expected, timeout; -+ ktime_t delta; -+ int update = 0; -+ -+ if (!bfq_bfqq_sync(bfqq) || bfq_bfqq_budget_new(bfqq)) -+ return 0; -+ -+ if (compensate) -+ delta = bfqd->last_idling_start; -+ else -+ delta = ktime_get(); -+ delta = ktime_sub(delta, bfqd->last_budget_start); -+ usecs = ktime_to_us(delta); -+ -+ /* Don't trust short/unrealistic values. */ -+ if (usecs < 100 || usecs >= LONG_MAX) -+ return 0; -+ -+ /* -+ * Calculate the bandwidth for the last slice. We use a 64 bit -+ * value to store the peak rate, in sectors per usec in fixed -+ * point math. We do so to have enough precision in the estimate -+ * and to avoid overflows. -+ */ -+ bw = (u64)bfqq->entity.service << BFQ_RATE_SHIFT; -+ do_div(bw, (unsigned long)usecs); -+ -+ timeout = jiffies_to_msecs(bfqd->bfq_timeout[BLK_RW_SYNC]); -+ -+ /* -+ * Use only long (> 20ms) intervals to filter out spikes for -+ * the peak rate estimation. -+ */ -+ if (usecs > 20000) { -+ if (bw > bfqd->peak_rate || -+ (!BFQQ_SEEKY(bfqq) && -+ reason == BFQ_BFQQ_BUDGET_TIMEOUT)) { -+ bfq_log(bfqd, "measured bw =%llu", bw); -+ /* -+ * To smooth oscillations use a low-pass filter with -+ * alpha=7/8, i.e., -+ * new_rate = (7/8) * old_rate + (1/8) * bw -+ */ -+ do_div(bw, 8); -+ if (bw == 0) -+ return 0; -+ bfqd->peak_rate *= 7; -+ do_div(bfqd->peak_rate, 8); -+ bfqd->peak_rate += bw; -+ update = 1; -+ bfq_log(bfqd, "new peak_rate=%llu", bfqd->peak_rate); -+ } -+ -+ update |= bfqd->peak_rate_samples == BFQ_PEAK_RATE_SAMPLES - 1; -+ -+ if (bfqd->peak_rate_samples < BFQ_PEAK_RATE_SAMPLES) -+ bfqd->peak_rate_samples++; -+ -+ if (bfqd->peak_rate_samples == BFQ_PEAK_RATE_SAMPLES && -+ update && bfqd->bfq_user_max_budget == 0) { -+ bfqd->bfq_max_budget = -+ bfq_calc_max_budget(bfqd->peak_rate, timeout); -+ bfq_log(bfqd, "new max_budget=%lu", -+ bfqd->bfq_max_budget); -+ } -+ } -+ -+ /* -+ * If the process has been served for a too short time -+ * interval to let its possible sequential accesses prevail on -+ * the initial seek time needed to move the disk head on the -+ * first sector it requested, then give the process a chance -+ * and for the moment return false. -+ */ -+ if (bfqq->entity.budget <= bfq_max_budget(bfqd) / 8) -+ return 0; -+ -+ /* -+ * A process is considered ``slow'' (i.e., seeky, so that we -+ * cannot treat it fairly in the service domain, as it would -+ * slow down too much the other processes) if, when a slice -+ * ends for whatever reason, it has received service at a -+ * rate that would not be high enough to complete the budget -+ * before the budget timeout expiration. -+ */ -+ expected = bw * 1000 * timeout >> BFQ_RATE_SHIFT; -+ -+ /* -+ * Caveat: processes doing IO in the slower disk zones will -+ * tend to be slow(er) even if not seeky. And the estimated -+ * peak rate will actually be an average over the disk -+ * surface. Hence, to not be too harsh with unlucky processes, -+ * we keep a budget/3 margin of safety before declaring a -+ * process slow. -+ */ -+ return expected > (4 * bfqq->entity.budget) / 3; -+} -+ -+/* -+ * To be deemed as soft real-time, an application must meet two requirements. -+ * The first is that the application must not require an average bandwidth -+ * higher than the approximate bandwidth required to playback or record a -+ * compressed high-definition video. -+ * The next function is invoked on the completion of the last request of a -+ * batch, to compute the next-start time instant, soft_rt_next_start, such -+ * that, if the next request of the application does not arrive before -+ * soft_rt_next_start, then the above requirement on the bandwidth is met. -+ * -+ * The second requirement is that the request pattern of the application is -+ * isochronous, i.e., that, after issuing a request or a batch of requests, the -+ * application stops for a while, then issues a new batch, and so on. For this -+ * reason the next function is invoked to compute soft_rt_next_start only for -+ * applications that meet this requirement, whereas soft_rt_next_start is set -+ * to infinity for applications that do not. -+ * -+ * Unfortunately, even a greedy application may happen to behave in an -+ * isochronous way if several processes are competing for the CPUs. In fact, -+ * in this scenario the application stops issuing requests while the CPUs are -+ * busy serving other processes, then restarts, then stops again for a while, -+ * and so on. In addition, if the disk achieves a low enough throughput with -+ * the request pattern issued by the application, then the above bandwidth -+ * requirement may happen to be met too. To prevent such a greedy application -+ * to be deemed as soft real-time, a further rule is used in the computation -+ * of soft_rt_next_start: soft_rt_next_start must be higher than the current -+ * time plus the maximum time for which the arrival of a request is waited -+ * for when a sync queue becomes idle, namely bfqd->bfq_slice_idle. This -+ * filters out greedy applications, as the latter issue instead their next -+ * request as soon as possible after the last one has been completed (in -+ * contrast, when a batch of requests is completed, a soft real-time -+ * application spends some time processing data). -+ * -+ * Actually, the last filter may easily generate false positives if: only -+ * bfqd->bfq_slice_idle is used as a reference time interval, and one or -+ * both the following two cases occur: -+ * 1) HZ is so low that the duration of a jiffie is comparable to or higher -+ * than bfqd->bfq_slice_idle. This happens, e.g., on slow devices with -+ * HZ=100. -+ * 2) jiffies, instead of increasing at a constant rate, may stop increasing -+ * for a while, then suddenly 'jump' by several units to recover the lost -+ * increments. This seems to happen, e.g., inside virtual machines. -+ * To address this issue, we do not use as a reference time interval just -+ * bfqd->bfq_slice_idle, but bfqd->bfq_slice_idle plus a few jiffies. In -+ * particular we add the minimum number of jiffies for which the filter seems -+ * to be quite precise also in embedded systems and KVM/QEMU virtual machines. -+ */ -+static inline u64 bfq_bfqq_softrt_next_start(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq) -+{ -+ return max(bfqq->last_idle_bklogged + -+ HZ * bfqq->service_from_backlogged / -+ bfqd->bfq_raising_max_softrt_rate, -+ (u64)jiffies + bfqq->bfqd->bfq_slice_idle + 4); -+} -+ -+/** -+ * bfq_bfqq_expire - expire a queue. -+ * @bfqd: device owning the queue. -+ * @bfqq: the queue to expire. -+ * @compensate: if true, compensate for the time spent idling. -+ * @reason: the reason causing the expiration. -+ * -+ * -+ * If the process associated to the queue is slow (i.e., seeky), or in -+ * case of budget timeout, or, finally, if it is async, we -+ * artificially charge it an entire budget (independently of the -+ * actual service it received). As a consequence, the queue will get -+ * higher timestamps than the correct ones upon reactivation, and -+ * hence it will be rescheduled as if it had received more service -+ * than what it actually received. In the end, this class of processes -+ * will receive less service in proportion to how slowly they consume -+ * their budgets (and hence how seriously they tend to lower the -+ * throughput). -+ * -+ * In contrast, when a queue expires because it has been idling for -+ * too much or because it exhausted its budget, we do not touch the -+ * amount of service it has received. Hence when the queue will be -+ * reactivated and its timestamps updated, the latter will be in sync -+ * with the actual service received by the queue until expiration. -+ * -+ * Charging a full budget to the first type of queues and the exact -+ * service to the others has the effect of using the WF2Q+ policy to -+ * schedule the former on a timeslice basis, without violating the -+ * service domain guarantees of the latter. -+ */ -+static void bfq_bfqq_expire(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq, -+ int compensate, -+ enum bfqq_expiration reason) -+{ -+ int slow; -+ BUG_ON(bfqq != bfqd->in_service_queue); -+ -+ /* Update disk peak rate for autotuning and check whether the -+ * process is slow (see bfq_update_peak_rate). -+ */ -+ slow = bfq_update_peak_rate(bfqd, bfqq, compensate, reason); -+ -+ /* -+ * As above explained, 'punish' slow (i.e., seeky), timed-out -+ * and async queues, to favor sequential sync workloads. -+ * -+ * Processes doing IO in the slower disk zones will tend to be -+ * slow(er) even if not seeky. Hence, since the estimated peak -+ * rate is actually an average over the disk surface, these -+ * processes may timeout just for bad luck. To avoid punishing -+ * them we do not charge a full budget to a process that -+ * succeeded in consuming at least 2/3 of its budget. -+ */ -+ if (slow || (reason == BFQ_BFQQ_BUDGET_TIMEOUT && -+ bfq_bfqq_budget_left(bfqq) >= bfqq->entity.budget / 3)) -+ bfq_bfqq_charge_full_budget(bfqq); -+ -+ bfqq->service_from_backlogged += bfqq->entity.service; -+ -+ if (bfqd->low_latency && bfqq->raising_coeff == 1) -+ bfqq->last_rais_start_finish = jiffies; -+ -+ if (bfqd->low_latency && bfqd->bfq_raising_max_softrt_rate > 0) { -+ if (reason != BFQ_BFQQ_BUDGET_TIMEOUT && -+ reason != BFQ_BFQQ_BUDGET_EXHAUSTED) { -+ /* -+ * If we get here, then the request pattern is -+ * isochronous (see the comments to the function -+ * bfq_bfqq_softrt_next_start()). However, if the -+ * queue still has in-flight requests, then it is -+ * better to postpone the computation of next_start -+ * to the next request completion. In fact, if we -+ * computed it now, then the application might pass -+ * the greedy-application filter improperly, because -+ * the arrival of its next request may happen to be -+ * higher than (jiffies + bfqq->bfqd->bfq_slice_idle) -+ * not because the application is truly soft real- -+ * time, but just because the application is currently -+ * waiting for the completion of some request before -+ * issuing, as quickly as possible, its next request. -+ */ -+ if (bfqq->dispatched > 0) { -+ bfqq->soft_rt_next_start = -1; -+ bfq_mark_bfqq_softrt_update(bfqq); -+ } else -+ bfqq->soft_rt_next_start = -+ bfq_bfqq_softrt_next_start(bfqd, bfqq); -+ } else -+ bfqq->soft_rt_next_start = -1; /* infinity */ -+ } -+ -+ bfq_log_bfqq(bfqd, bfqq, -+ "expire (%d, slow %d, num_disp %d, idle_win %d)", reason, slow, -+ bfqq->dispatched, bfq_bfqq_idle_window(bfqq)); -+ -+ /* Increase, decrease or leave budget unchanged according to reason */ -+ __bfq_bfqq_recalc_budget(bfqd, bfqq, reason); -+ __bfq_bfqq_expire(bfqd, bfqq); -+} -+ -+/* -+ * Budget timeout is not implemented through a dedicated timer, but -+ * just checked on request arrivals and completions, as well as on -+ * idle timer expirations. -+ */ -+static int bfq_bfqq_budget_timeout(struct bfq_queue *bfqq) -+{ -+ if (bfq_bfqq_budget_new(bfqq)) -+ return 0; -+ -+ if (time_before(jiffies, bfqq->budget_timeout)) -+ return 0; -+ -+ return 1; -+} -+ -+/* -+ * If we expire a queue that is waiting for the arrival of a new -+ * request, we may prevent the fictitious timestamp backshifting that -+ * allows the guarantees of the queue to be preserved (see [1] for -+ * this tricky aspect). Hence we return true only if this condition -+ * does not hold, or if the queue is slow enough to deserve only to be -+ * kicked off for preserving a high throughput. -+*/ -+static inline int bfq_may_expire_for_budg_timeout(struct bfq_queue *bfqq) -+{ -+ bfq_log_bfqq(bfqq->bfqd, bfqq, -+ "may_budget_timeout: wr %d left %d timeout %d", -+ bfq_bfqq_wait_request(bfqq), -+ bfq_bfqq_budget_left(bfqq) >= bfqq->entity.budget / 3, -+ bfq_bfqq_budget_timeout(bfqq)); -+ -+ return (!bfq_bfqq_wait_request(bfqq) || -+ bfq_bfqq_budget_left(bfqq) >= bfqq->entity.budget / 3) -+ && -+ bfq_bfqq_budget_timeout(bfqq); -+} -+ -+/* -+ * For weight-raised queues issuing sync requests, idling is always performed, -+ * as this is instrumental in guaranteeing a high fraction of the throughput -+ * to these queues, and hence in guaranteeing a lower latency for their -+ * requests. See [1] for details. -+ * -+ * For non-weight-raised queues, idling is instead disabled if the device is -+ * NCQ-enabled and non-rotational, as this boosts the throughput on such -+ * devices. -+ */ -+static inline bool bfq_bfqq_must_not_expire(struct bfq_queue *bfqq) -+{ -+ struct bfq_data *bfqd = bfqq->bfqd; -+ -+ return bfq_bfqq_sync(bfqq) && ( -+ bfqq->raising_coeff > 1 || -+ (bfq_bfqq_idle_window(bfqq) && -+ !(bfqd->hw_tag && -+ (blk_queue_nonrot(bfqd->queue) || -+ /* -+ * If there are weight-raised busy queues, then do not idle -+ * the disk for a sync non-weight-raised queue, and hence -+ * expire the queue immediately if empty. Combined with the -+ * timestamping rules of BFQ (see [1] for details), this -+ * causes sync non-weight-raised queues to get a lower -+ * fraction of the disk throughput, and hence reduces the rate -+ * at which the processes associated to these queues ask for -+ * requests from the request pool. -+ * -+ * This is beneficial for weight-raised processes, when the -+ * system operates in request-pool saturation conditions -+ * (e.g., in the presence of write hogs). In fact, if -+ * non-weight-raised processes ask for requests at a lower -+ * rate, then weight-raised processes have a higher -+ * probability to get a request from the pool immediately -+ * (or at least soon) when they need one. Hence they have a -+ * higher probability to actually get a fraction of the disk -+ * throughput proportional to their high weight. This is -+ * especially true with NCQ-enabled drives, which enqueue -+ * several requests in advance and further reorder -+ * internally-queued requests. -+ * -+ * Mistreating non-weight-raised queues in the above-described -+ * way, when there are busy weight-raised queues, seems to -+ * mitigate starvation problems in the presence of heavy write -+ * workloads and NCQ, and hence to guarantee a higher -+ * application and system responsiveness in these hostile -+ * scenarios. -+ */ -+ bfqd->raised_busy_queues > 0) -+ ) -+ ) -+ ); -+} -+ -+/* -+ * If the in-service queue is empty, but it is sync and either of the following -+ * conditions holds, then: 1) the queue must remain in service and cannot be -+ * expired, and 2) the disk must be idled to wait for the possible arrival -+ * of a new request for the queue. The conditions are: -+ * - the device is rotational and not performing NCQ, and the queue has its -+ * idle window set (in this case, waiting for a new request for the queue -+ * is likely to boost the disk throughput); -+ * - the queue is weight-raised (waiting for the request is necessary to -+ * provide the queue with fairness and latency guarantees, see [1] for -+ * details). -+ */ -+static inline bool bfq_bfqq_must_idle(struct bfq_queue *bfqq) -+{ -+ struct bfq_data *bfqd = bfqq->bfqd; -+ -+ return (RB_EMPTY_ROOT(&bfqq->sort_list) && bfqd->bfq_slice_idle != 0 && -+ bfq_bfqq_must_not_expire(bfqq) && -+ !bfq_queue_nonrot_noidle(bfqd, bfqq)); -+} -+ -+/* -+ * Select a queue for service. If we have a current queue in service, -+ * check whether to continue servicing it, or retrieve and set a new one. -+ */ -+static struct bfq_queue *bfq_select_queue(struct bfq_data *bfqd) -+{ -+ struct bfq_queue *bfqq, *new_bfqq = NULL; -+ struct request *next_rq; -+ enum bfqq_expiration reason = BFQ_BFQQ_BUDGET_TIMEOUT; -+ -+ bfqq = bfqd->in_service_queue; -+ if (bfqq == NULL) -+ goto new_queue; -+ -+ bfq_log_bfqq(bfqd, bfqq, "select_queue: already in-service queue"); -+ -+ /* -+ * If another queue has a request waiting within our mean seek -+ * distance, let it run. The expire code will check for close -+ * cooperators and put the close queue at the front of the -+ * service tree. If possible, merge the expiring queue with the -+ * new bfqq. -+ */ -+ new_bfqq = bfq_close_cooperator(bfqd, bfqq); -+ if (new_bfqq != NULL && bfqq->new_bfqq == NULL) -+ bfq_setup_merge(bfqq, new_bfqq); -+ -+ if (bfq_may_expire_for_budg_timeout(bfqq) && -+ !timer_pending(&bfqd->idle_slice_timer) && -+ !bfq_bfqq_must_idle(bfqq)) -+ goto expire; -+ -+ next_rq = bfqq->next_rq; -+ /* -+ * If bfqq has requests queued and it has enough budget left to -+ * serve them, keep the queue, otherwise expire it. -+ */ -+ if (next_rq != NULL) { -+ if (bfq_serv_to_charge(next_rq, bfqq) > -+ bfq_bfqq_budget_left(bfqq)) { -+ reason = BFQ_BFQQ_BUDGET_EXHAUSTED; -+ goto expire; -+ } else { -+ /* -+ * The idle timer may be pending because we may not -+ * disable disk idling even when a new request arrives -+ */ -+ if (timer_pending(&bfqd->idle_slice_timer)) { -+ /* -+ * If we get here: 1) at least a new request -+ * has arrived but we have not disabled the -+ * timer because the request was too small, -+ * 2) then the block layer has unplugged the -+ * device, causing the dispatch to be invoked. -+ * -+ * Since the device is unplugged, now the -+ * requests are probably large enough to -+ * provide a reasonable throughput. -+ * So we disable idling. -+ */ -+ bfq_clear_bfqq_wait_request(bfqq); -+ del_timer(&bfqd->idle_slice_timer); -+ } -+ if (new_bfqq == NULL) -+ goto keep_queue; -+ else -+ goto expire; -+ } -+ } -+ -+ /* -+ * No requests pending. If the in-service queue has no cooperator and -+ * still has requests in flight (possibly waiting for a completion) -+ * or is idling for a new request, then keep it. -+ */ -+ if (new_bfqq == NULL && (timer_pending(&bfqd->idle_slice_timer) || -+ (bfqq->dispatched != 0 && bfq_bfqq_must_not_expire(bfqq)))) { -+ bfqq = NULL; -+ goto keep_queue; -+ } else if (new_bfqq != NULL && timer_pending(&bfqd->idle_slice_timer)) { -+ /* -+ * Expiring the queue because there is a close cooperator, -+ * cancel timer. -+ */ -+ bfq_clear_bfqq_wait_request(bfqq); -+ del_timer(&bfqd->idle_slice_timer); -+ } -+ -+ reason = BFQ_BFQQ_NO_MORE_REQUESTS; -+expire: -+ bfq_bfqq_expire(bfqd, bfqq, 0, reason); -+new_queue: -+ bfqq = bfq_set_in_service_queue(bfqd, new_bfqq); -+ bfq_log(bfqd, "select_queue: new queue %d returned", -+ bfqq != NULL ? bfqq->pid : 0); -+keep_queue: -+ return bfqq; -+} -+ -+static void bfq_update_raising_data(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq) -+{ -+ if (bfqq->raising_coeff > 1) { /* queue is being boosted */ -+ struct bfq_entity *entity = &bfqq->entity; -+ -+ bfq_log_bfqq(bfqd, bfqq, -+ "raising period dur %u/%u msec, " -+ "old raising coeff %u, w %d(%d)", -+ jiffies_to_msecs(jiffies - -+ bfqq->last_rais_start_finish), -+ jiffies_to_msecs(bfqq->raising_cur_max_time), -+ bfqq->raising_coeff, -+ bfqq->entity.weight, bfqq->entity.orig_weight); -+ -+ BUG_ON(bfqq != bfqd->in_service_queue && entity->weight != -+ entity->orig_weight * bfqq->raising_coeff); -+ if (entity->ioprio_changed) -+ bfq_log_bfqq(bfqd, bfqq, -+ "WARN: pending prio change"); -+ /* -+ * If too much time has elapsed from the beginning -+ * of this weight-raising, stop it. -+ */ -+ if (jiffies - bfqq->last_rais_start_finish > -+ bfqq->raising_cur_max_time) { -+ bfqq->last_rais_start_finish = jiffies; -+ bfq_log_bfqq(bfqd, bfqq, -+ "wrais ending at %llu msec," -+ "rais_max_time %u", -+ bfqq->last_rais_start_finish, -+ jiffies_to_msecs(bfqq-> -+ raising_cur_max_time)); -+ bfq_bfqq_end_raising(bfqq); -+ __bfq_entity_update_weight_prio( -+ bfq_entity_service_tree(entity), -+ entity); -+ } -+ } -+} -+ -+/* -+ * Dispatch one request from bfqq, moving it to the request queue -+ * dispatch list. -+ */ -+static int bfq_dispatch_request(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq) -+{ -+ int dispatched = 0; -+ struct request *rq; -+ unsigned long service_to_charge; -+ -+ BUG_ON(RB_EMPTY_ROOT(&bfqq->sort_list)); -+ -+ /* Follow expired path, else get first next available. */ -+ rq = bfq_check_fifo(bfqq); -+ if (rq == NULL) -+ rq = bfqq->next_rq; -+ service_to_charge = bfq_serv_to_charge(rq, bfqq); -+ -+ if (service_to_charge > bfq_bfqq_budget_left(bfqq)) { -+ /* -+ * This may happen if the next rq is chosen -+ * in fifo order instead of sector order. -+ * The budget is properly dimensioned -+ * to be always sufficient to serve the next request -+ * only if it is chosen in sector order. The reason is -+ * that it would be quite inefficient and little useful -+ * to always make sure that the budget is large enough -+ * to serve even the possible next rq in fifo order. -+ * In fact, requests are seldom served in fifo order. -+ * -+ * Expire the queue for budget exhaustion, and -+ * make sure that the next act_budget is enough -+ * to serve the next request, even if it comes -+ * from the fifo expired path. -+ */ -+ bfqq->next_rq = rq; -+ /* -+ * Since this dispatch is failed, make sure that -+ * a new one will be performed -+ */ -+ if (!bfqd->rq_in_driver) -+ bfq_schedule_dispatch(bfqd); -+ goto expire; -+ } -+ -+ /* Finally, insert request into driver dispatch list. */ -+ bfq_bfqq_served(bfqq, service_to_charge); -+ bfq_dispatch_insert(bfqd->queue, rq); -+ -+ bfq_update_raising_data(bfqd, bfqq); -+ -+ bfq_log_bfqq(bfqd, bfqq, -+ "dispatched %u sec req (%llu), budg left %lu", -+ blk_rq_sectors(rq), -+ (long long unsigned)blk_rq_pos(rq), -+ bfq_bfqq_budget_left(bfqq)); -+ -+ dispatched++; -+ -+ if (bfqd->in_service_bic == NULL) { -+ atomic_long_inc(&RQ_BIC(rq)->icq.ioc->refcount); -+ bfqd->in_service_bic = RQ_BIC(rq); -+ } -+ -+ if (bfqd->busy_queues > 1 && ((!bfq_bfqq_sync(bfqq) && -+ dispatched >= bfqd->bfq_max_budget_async_rq) || -+ bfq_class_idle(bfqq))) -+ goto expire; -+ -+ return dispatched; -+ -+expire: -+ bfq_bfqq_expire(bfqd, bfqq, 0, BFQ_BFQQ_BUDGET_EXHAUSTED); -+ return dispatched; -+} -+ -+static int __bfq_forced_dispatch_bfqq(struct bfq_queue *bfqq) -+{ -+ int dispatched = 0; -+ -+ while (bfqq->next_rq != NULL) { -+ bfq_dispatch_insert(bfqq->bfqd->queue, bfqq->next_rq); -+ dispatched++; -+ } -+ -+ BUG_ON(!list_empty(&bfqq->fifo)); -+ return dispatched; -+} -+ -+/* -+ * Drain our current requests. Used for barriers and when switching -+ * io schedulers on-the-fly. -+ */ -+static int bfq_forced_dispatch(struct bfq_data *bfqd) -+{ -+ struct bfq_queue *bfqq, *n; -+ struct bfq_service_tree *st; -+ int dispatched = 0; -+ -+ bfqq = bfqd->in_service_queue; -+ if (bfqq != NULL) -+ __bfq_bfqq_expire(bfqd, bfqq); -+ -+ /* -+ * Loop through classes, and be careful to leave the scheduler -+ * in a consistent state, as feedback mechanisms and vtime -+ * updates cannot be disabled during the process. -+ */ -+ list_for_each_entry_safe(bfqq, n, &bfqd->active_list, bfqq_list) { -+ st = bfq_entity_service_tree(&bfqq->entity); -+ -+ dispatched += __bfq_forced_dispatch_bfqq(bfqq); -+ bfqq->max_budget = bfq_max_budget(bfqd); -+ -+ bfq_forget_idle(st); -+ } -+ -+ BUG_ON(bfqd->busy_queues != 0); -+ -+ return dispatched; -+} -+ -+static int bfq_dispatch_requests(struct request_queue *q, int force) -+{ -+ struct bfq_data *bfqd = q->elevator->elevator_data; -+ struct bfq_queue *bfqq; -+ int max_dispatch; -+ -+ bfq_log(bfqd, "dispatch requests: %d busy queues", bfqd->busy_queues); -+ if (bfqd->busy_queues == 0) -+ return 0; -+ -+ if (unlikely(force)) -+ return bfq_forced_dispatch(bfqd); -+ -+ bfqq = bfq_select_queue(bfqd); -+ if (bfqq == NULL) -+ return 0; -+ -+ max_dispatch = bfqd->bfq_quantum; -+ if (bfq_class_idle(bfqq)) -+ max_dispatch = 1; -+ -+ if (!bfq_bfqq_sync(bfqq)) -+ max_dispatch = bfqd->bfq_max_budget_async_rq; -+ -+ if (bfqq->dispatched >= max_dispatch) { -+ if (bfqd->busy_queues > 1) -+ return 0; -+ if (bfqq->dispatched >= 4 * max_dispatch) -+ return 0; -+ } -+ -+ if (bfqd->sync_flight != 0 && !bfq_bfqq_sync(bfqq)) -+ return 0; -+ -+ bfq_clear_bfqq_wait_request(bfqq); -+ BUG_ON(timer_pending(&bfqd->idle_slice_timer)); -+ -+ if (!bfq_dispatch_request(bfqd, bfqq)) -+ return 0; -+ -+ bfq_log_bfqq(bfqd, bfqq, "dispatched one request of %d (max_disp %d)", -+ bfqq->pid, max_dispatch); -+ -+ return 1; -+} -+ -+/* -+ * Task holds one reference to the queue, dropped when task exits. Each rq -+ * in-flight on this queue also holds a reference, dropped when rq is freed. -+ * -+ * Queue lock must be held here. -+ */ -+static void bfq_put_queue(struct bfq_queue *bfqq) -+{ -+ struct bfq_data *bfqd = bfqq->bfqd; -+ -+ BUG_ON(atomic_read(&bfqq->ref) <= 0); -+ -+ bfq_log_bfqq(bfqd, bfqq, "put_queue: %p %d", bfqq, -+ atomic_read(&bfqq->ref)); -+ if (!atomic_dec_and_test(&bfqq->ref)) -+ return; -+ -+ BUG_ON(rb_first(&bfqq->sort_list) != NULL); -+ BUG_ON(bfqq->allocated[READ] + bfqq->allocated[WRITE] != 0); -+ BUG_ON(bfqq->entity.tree != NULL); -+ BUG_ON(bfq_bfqq_busy(bfqq)); -+ BUG_ON(bfqd->in_service_queue == bfqq); -+ -+ bfq_log_bfqq(bfqd, bfqq, "put_queue: %p freed", bfqq); -+ -+ kmem_cache_free(bfq_pool, bfqq); -+} -+ -+static void bfq_put_cooperator(struct bfq_queue *bfqq) -+{ -+ struct bfq_queue *__bfqq, *next; -+ -+ /* -+ * If this queue was scheduled to merge with another queue, be -+ * sure to drop the reference taken on that queue (and others in -+ * the merge chain). See bfq_setup_merge and bfq_merge_bfqqs. -+ */ -+ __bfqq = bfqq->new_bfqq; -+ while (__bfqq) { -+ if (__bfqq == bfqq) { -+ WARN(1, "bfqq->new_bfqq loop detected.\n"); -+ break; -+ } -+ next = __bfqq->new_bfqq; -+ bfq_put_queue(__bfqq); -+ __bfqq = next; -+ } -+} -+ -+static void bfq_exit_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq) -+{ -+ if (bfqq == bfqd->in_service_queue) { -+ __bfq_bfqq_expire(bfqd, bfqq); -+ bfq_schedule_dispatch(bfqd); -+ } -+ -+ bfq_log_bfqq(bfqd, bfqq, "exit_bfqq: %p, %d", bfqq, -+ atomic_read(&bfqq->ref)); -+ -+ bfq_put_cooperator(bfqq); -+ -+ bfq_put_queue(bfqq); -+} -+ -+static void bfq_init_icq(struct io_cq *icq) -+{ -+ struct bfq_io_cq *bic = icq_to_bic(icq); -+ -+ bic->ttime.last_end_request = jiffies; -+} -+ -+static void bfq_exit_icq(struct io_cq *icq) -+{ -+ struct bfq_io_cq *bic = icq_to_bic(icq); -+ struct bfq_data *bfqd = bic_to_bfqd(bic); -+ -+ if (bic->bfqq[BLK_RW_ASYNC]) { -+ bfq_exit_bfqq(bfqd, bic->bfqq[BLK_RW_ASYNC]); -+ bic->bfqq[BLK_RW_ASYNC] = NULL; -+ } -+ -+ if (bic->bfqq[BLK_RW_SYNC]) { -+ bfq_exit_bfqq(bfqd, bic->bfqq[BLK_RW_SYNC]); -+ bic->bfqq[BLK_RW_SYNC] = NULL; -+ } -+} -+ -+/* -+ * Update the entity prio values; note that the new values will not -+ * be used until the next (re)activation. -+ */ -+static void bfq_init_prio_data(struct bfq_queue *bfqq, struct bfq_io_cq *bic) -+{ -+ struct task_struct *tsk = current; -+ int ioprio_class; -+ -+ if (!bfq_bfqq_prio_changed(bfqq)) -+ return; -+ -+ ioprio_class = IOPRIO_PRIO_CLASS(bic->ioprio); -+ switch (ioprio_class) { -+ default: -+ dev_err(bfqq->bfqd->queue->backing_dev_info.dev, -+ "bfq: bad prio %x\n", ioprio_class); -+ case IOPRIO_CLASS_NONE: -+ /* -+ * No prio set, inherit CPU scheduling settings. -+ */ -+ bfqq->entity.new_ioprio = task_nice_ioprio(tsk); -+ bfqq->entity.new_ioprio_class = task_nice_ioclass(tsk); -+ break; -+ case IOPRIO_CLASS_RT: -+ bfqq->entity.new_ioprio = IOPRIO_PRIO_DATA(bic->ioprio); -+ bfqq->entity.new_ioprio_class = IOPRIO_CLASS_RT; -+ break; -+ case IOPRIO_CLASS_BE: -+ bfqq->entity.new_ioprio = IOPRIO_PRIO_DATA(bic->ioprio); -+ bfqq->entity.new_ioprio_class = IOPRIO_CLASS_BE; -+ break; -+ case IOPRIO_CLASS_IDLE: -+ bfqq->entity.new_ioprio_class = IOPRIO_CLASS_IDLE; -+ bfqq->entity.new_ioprio = 7; -+ bfq_clear_bfqq_idle_window(bfqq); -+ break; -+ } -+ -+ bfqq->entity.ioprio_changed = 1; -+ -+ /* -+ * Keep track of original prio settings in case we have to temporarily -+ * elevate the priority of this queue. -+ */ -+ bfqq->org_ioprio = bfqq->entity.new_ioprio; -+ bfq_clear_bfqq_prio_changed(bfqq); -+} -+ -+static void bfq_changed_ioprio(struct bfq_io_cq *bic) -+{ -+ struct bfq_data *bfqd; -+ struct bfq_queue *bfqq, *new_bfqq; -+ struct bfq_group *bfqg; -+ unsigned long uninitialized_var(flags); -+ int ioprio = bic->icq.ioc->ioprio; -+ -+ bfqd = bfq_get_bfqd_locked(&(bic->icq.q->elevator->elevator_data), -+ &flags); -+ /* -+ * This condition may trigger on a newly created bic, be sure to drop -+ * the lock before returning. -+ */ -+ if (unlikely(bfqd == NULL) || likely(bic->ioprio == ioprio)) -+ goto out; -+ -+ bfqq = bic->bfqq[BLK_RW_ASYNC]; -+ if (bfqq != NULL) { -+ bfqg = container_of(bfqq->entity.sched_data, struct bfq_group, -+ sched_data); -+ new_bfqq = bfq_get_queue(bfqd, bfqg, BLK_RW_ASYNC, bic, -+ GFP_ATOMIC); -+ if (new_bfqq != NULL) { -+ bic->bfqq[BLK_RW_ASYNC] = new_bfqq; -+ bfq_log_bfqq(bfqd, bfqq, -+ "changed_ioprio: bfqq %p %d", -+ bfqq, atomic_read(&bfqq->ref)); -+ bfq_put_queue(bfqq); -+ } -+ } -+ -+ bfqq = bic->bfqq[BLK_RW_SYNC]; -+ if (bfqq != NULL) -+ bfq_mark_bfqq_prio_changed(bfqq); -+ -+ bic->ioprio = ioprio; -+ -+out: -+ bfq_put_bfqd_unlock(bfqd, &flags); -+} -+ -+static void bfq_init_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq, -+ pid_t pid, int is_sync) -+{ -+ RB_CLEAR_NODE(&bfqq->entity.rb_node); -+ INIT_LIST_HEAD(&bfqq->fifo); -+ -+ atomic_set(&bfqq->ref, 0); -+ bfqq->bfqd = bfqd; -+ -+ bfq_mark_bfqq_prio_changed(bfqq); -+ -+ if (is_sync) { -+ if (!bfq_class_idle(bfqq)) -+ bfq_mark_bfqq_idle_window(bfqq); -+ bfq_mark_bfqq_sync(bfqq); -+ } -+ -+ /* Tentative initial value to trade off between thr and lat */ -+ bfqq->max_budget = (2 * bfq_max_budget(bfqd)) / 3; -+ bfqq->pid = pid; -+ -+ bfqq->raising_coeff = 1; -+ bfqq->last_rais_start_finish = 0; -+ bfqq->soft_rt_next_start = -1; -+} -+ -+static struct bfq_queue *bfq_find_alloc_queue(struct bfq_data *bfqd, -+ struct bfq_group *bfqg, -+ int is_sync, -+ struct bfq_io_cq *bic, -+ gfp_t gfp_mask) -+{ -+ struct bfq_queue *bfqq, *new_bfqq = NULL; -+ -+retry: -+ /* bic always exists here */ -+ bfqq = bic_to_bfqq(bic, is_sync); -+ -+ /* -+ * Always try a new alloc if we fall back to the OOM bfqq -+ * originally, since it should just be a temporary situation. -+ */ -+ if (bfqq == NULL || bfqq == &bfqd->oom_bfqq) { -+ bfqq = NULL; -+ if (new_bfqq != NULL) { -+ bfqq = new_bfqq; -+ new_bfqq = NULL; -+ } else if (gfp_mask & __GFP_WAIT) { -+ spin_unlock_irq(bfqd->queue->queue_lock); -+ new_bfqq = kmem_cache_alloc_node(bfq_pool, -+ gfp_mask | __GFP_ZERO, -+ bfqd->queue->node); -+ spin_lock_irq(bfqd->queue->queue_lock); -+ if (new_bfqq != NULL) -+ goto retry; -+ } else { -+ bfqq = kmem_cache_alloc_node(bfq_pool, -+ gfp_mask | __GFP_ZERO, -+ bfqd->queue->node); -+ } -+ -+ if (bfqq != NULL) { -+ bfq_init_bfqq(bfqd, bfqq, current->pid, is_sync); -+ bfq_log_bfqq(bfqd, bfqq, "allocated"); -+ } else { -+ bfqq = &bfqd->oom_bfqq; -+ bfq_log_bfqq(bfqd, bfqq, "using oom bfqq"); -+ } -+ -+ bfq_init_prio_data(bfqq, bic); -+ bfq_init_entity(&bfqq->entity, bfqg); -+ } -+ -+ if (new_bfqq != NULL) -+ kmem_cache_free(bfq_pool, new_bfqq); -+ -+ return bfqq; -+} -+ -+static struct bfq_queue **bfq_async_queue_prio(struct bfq_data *bfqd, -+ struct bfq_group *bfqg, -+ int ioprio_class, int ioprio) -+{ -+ switch (ioprio_class) { -+ case IOPRIO_CLASS_RT: -+ return &bfqg->async_bfqq[0][ioprio]; -+ case IOPRIO_CLASS_NONE: -+ ioprio = IOPRIO_NORM; -+ /* fall through */ -+ case IOPRIO_CLASS_BE: -+ return &bfqg->async_bfqq[1][ioprio]; -+ case IOPRIO_CLASS_IDLE: -+ return &bfqg->async_idle_bfqq; -+ default: -+ BUG(); -+ } -+} -+ -+static struct bfq_queue *bfq_get_queue(struct bfq_data *bfqd, -+ struct bfq_group *bfqg, int is_sync, -+ struct bfq_io_cq *bic, gfp_t gfp_mask) -+{ -+ const int ioprio = IOPRIO_PRIO_DATA(bic->ioprio); -+ const int ioprio_class = IOPRIO_PRIO_CLASS(bic->ioprio); -+ struct bfq_queue **async_bfqq = NULL; -+ struct bfq_queue *bfqq = NULL; -+ -+ if (!is_sync) { -+ async_bfqq = bfq_async_queue_prio(bfqd, bfqg, ioprio_class, -+ ioprio); -+ bfqq = *async_bfqq; -+ } -+ -+ if (bfqq == NULL) -+ bfqq = bfq_find_alloc_queue(bfqd, bfqg, is_sync, bic, gfp_mask); -+ -+ /* -+ * Pin the queue now that it's allocated, scheduler exit will prune it. -+ */ -+ if (!is_sync && *async_bfqq == NULL) { -+ atomic_inc(&bfqq->ref); -+ bfq_log_bfqq(bfqd, bfqq, "get_queue, bfqq not in async: %p, %d", -+ bfqq, atomic_read(&bfqq->ref)); -+ *async_bfqq = bfqq; -+ } -+ -+ atomic_inc(&bfqq->ref); -+ bfq_log_bfqq(bfqd, bfqq, "get_queue, at end: %p, %d", bfqq, -+ atomic_read(&bfqq->ref)); -+ return bfqq; -+} -+ -+static void bfq_update_io_thinktime(struct bfq_data *bfqd, -+ struct bfq_io_cq *bic) -+{ -+ unsigned long elapsed = jiffies - bic->ttime.last_end_request; -+ unsigned long ttime = min(elapsed, 2UL * bfqd->bfq_slice_idle); -+ -+ bic->ttime.ttime_samples = (7*bic->ttime.ttime_samples + 256) / 8; -+ bic->ttime.ttime_total = (7*bic->ttime.ttime_total + 256*ttime) / 8; -+ bic->ttime.ttime_mean = (bic->ttime.ttime_total + 128) / -+ bic->ttime.ttime_samples; -+} -+ -+static void bfq_update_io_seektime(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq, -+ struct request *rq) -+{ -+ sector_t sdist; -+ u64 total; -+ -+ if (bfqq->last_request_pos < blk_rq_pos(rq)) -+ sdist = blk_rq_pos(rq) - bfqq->last_request_pos; -+ else -+ sdist = bfqq->last_request_pos - blk_rq_pos(rq); -+ -+ /* -+ * Don't allow the seek distance to get too large from the -+ * odd fragment, pagein, etc. -+ */ -+ if (bfqq->seek_samples == 0) /* first request, not really a seek */ -+ sdist = 0; -+ else if (bfqq->seek_samples <= 60) /* second & third seek */ -+ sdist = min(sdist, (bfqq->seek_mean * 4) + 2*1024*1024); -+ else -+ sdist = min(sdist, (bfqq->seek_mean * 4) + 2*1024*64); -+ -+ bfqq->seek_samples = (7*bfqq->seek_samples + 256) / 8; -+ bfqq->seek_total = (7*bfqq->seek_total + (u64)256*sdist) / 8; -+ total = bfqq->seek_total + (bfqq->seek_samples/2); -+ do_div(total, bfqq->seek_samples); -+ bfqq->seek_mean = (sector_t)total; -+ -+ bfq_log_bfqq(bfqd, bfqq, "dist=%llu mean=%llu", (u64)sdist, -+ (u64)bfqq->seek_mean); -+} -+ -+/* -+ * Disable idle window if the process thinks too long or seeks so much that -+ * it doesn't matter. -+ */ -+static void bfq_update_idle_window(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq, -+ struct bfq_io_cq *bic) -+{ -+ int enable_idle; -+ -+ /* Don't idle for async or idle io prio class. */ -+ if (!bfq_bfqq_sync(bfqq) || bfq_class_idle(bfqq)) -+ return; -+ -+ enable_idle = bfq_bfqq_idle_window(bfqq); -+ -+ if (atomic_read(&bic->icq.ioc->active_ref) == 0 || -+ bfqd->bfq_slice_idle == 0 || -+ (bfqd->hw_tag && BFQQ_SEEKY(bfqq) && -+ bfqq->raising_coeff == 1)) -+ enable_idle = 0; -+ else if (bfq_sample_valid(bic->ttime.ttime_samples)) { -+ if (bic->ttime.ttime_mean > bfqd->bfq_slice_idle && -+ bfqq->raising_coeff == 1) -+ enable_idle = 0; -+ else -+ enable_idle = 1; -+ } -+ bfq_log_bfqq(bfqd, bfqq, "update_idle_window: enable_idle %d", -+ enable_idle); -+ -+ if (enable_idle) -+ bfq_mark_bfqq_idle_window(bfqq); -+ else -+ bfq_clear_bfqq_idle_window(bfqq); -+} -+ -+/* -+ * Called when a new fs request (rq) is added to bfqq. Check if there's -+ * something we should do about it. -+ */ -+static void bfq_rq_enqueued(struct bfq_data *bfqd, struct bfq_queue *bfqq, -+ struct request *rq) -+{ -+ struct bfq_io_cq *bic = RQ_BIC(rq); -+ -+ if (rq->cmd_flags & REQ_META) -+ bfqq->meta_pending++; -+ -+ bfq_update_io_thinktime(bfqd, bic); -+ bfq_update_io_seektime(bfqd, bfqq, rq); -+ if (bfqq->entity.service > bfq_max_budget(bfqd) / 8 || -+ !BFQQ_SEEKY(bfqq)) -+ bfq_update_idle_window(bfqd, bfqq, bic); -+ -+ bfq_log_bfqq(bfqd, bfqq, -+ "rq_enqueued: idle_window=%d (seeky %d, mean %llu)", -+ bfq_bfqq_idle_window(bfqq), BFQQ_SEEKY(bfqq), -+ (long long unsigned)bfqq->seek_mean); -+ -+ bfqq->last_request_pos = blk_rq_pos(rq) + blk_rq_sectors(rq); -+ -+ if (bfqq == bfqd->in_service_queue && bfq_bfqq_wait_request(bfqq)) { -+ int small_req = bfqq->queued[rq_is_sync(rq)] == 1 && -+ blk_rq_sectors(rq) < 32; -+ int budget_timeout = bfq_bfqq_budget_timeout(bfqq); -+ -+ /* -+ * There is just this request queued: if the request -+ * is small and the queue is not to be expired, then -+ * just exit. -+ * -+ * In this way, if the disk is being idled to wait for -+ * a new request from the in-service queue, we avoid -+ * unplugging the device and committing the disk to serve -+ * just a small request. On the contrary, we wait for -+ * the block layer to decide when to unplug the device: -+ * hopefully, new requests will be merged to this one -+ * quickly, then the device will be unplugged and -+ * larger requests will be dispatched. -+ */ -+ if (small_req && !budget_timeout) -+ return; -+ -+ /* -+ * A large enough request arrived, or the queue is to -+ * be expired: in both cases disk idling is to be -+ * stopped, so clear wait_request flag and reset -+ * timer. -+ */ -+ bfq_clear_bfqq_wait_request(bfqq); -+ del_timer(&bfqd->idle_slice_timer); -+ -+ /* -+ * The queue is not empty, because a new request just -+ * arrived. Hence we can safely expire the queue, in -+ * case of budget timeout, without risking that the -+ * timestamps of the queue are not updated correctly. -+ * See [1] for more details. -+ */ -+ if (budget_timeout) -+ bfq_bfqq_expire(bfqd, bfqq, 0, BFQ_BFQQ_BUDGET_TIMEOUT); -+ -+ /* -+ * Let the request rip immediately, or let a new queue be -+ * selected if bfqq has just been expired. -+ */ -+ __blk_run_queue(bfqd->queue); -+ } -+} -+ -+static void bfq_insert_request(struct request_queue *q, struct request *rq) -+{ -+ struct bfq_data *bfqd = q->elevator->elevator_data; -+ struct bfq_queue *bfqq = RQ_BFQQ(rq); -+ -+ assert_spin_locked(bfqd->queue->queue_lock); -+ bfq_init_prio_data(bfqq, RQ_BIC(rq)); -+ -+ bfq_add_rq_rb(rq); -+ -+ rq_set_fifo_time(rq, jiffies + bfqd->bfq_fifo_expire[rq_is_sync(rq)]); -+ list_add_tail(&rq->queuelist, &bfqq->fifo); -+ -+ bfq_rq_enqueued(bfqd, bfqq, rq); -+} -+ -+static void bfq_update_hw_tag(struct bfq_data *bfqd) -+{ -+ bfqd->max_rq_in_driver = max(bfqd->max_rq_in_driver, -+ bfqd->rq_in_driver); -+ -+ if (bfqd->hw_tag == 1) -+ return; -+ -+ /* -+ * This sample is valid if the number of outstanding requests -+ * is large enough to allow a queueing behavior. Note that the -+ * sum is not exact, as it's not taking into account deactivated -+ * requests. -+ */ -+ if (bfqd->rq_in_driver + bfqd->queued < BFQ_HW_QUEUE_THRESHOLD) -+ return; -+ -+ if (bfqd->hw_tag_samples++ < BFQ_HW_QUEUE_SAMPLES) -+ return; -+ -+ bfqd->hw_tag = bfqd->max_rq_in_driver > BFQ_HW_QUEUE_THRESHOLD; -+ bfqd->max_rq_in_driver = 0; -+ bfqd->hw_tag_samples = 0; -+} -+ -+static void bfq_completed_request(struct request_queue *q, struct request *rq) -+{ -+ struct bfq_queue *bfqq = RQ_BFQQ(rq); -+ struct bfq_data *bfqd = bfqq->bfqd; -+ const int sync = rq_is_sync(rq); -+ -+ bfq_log_bfqq(bfqd, bfqq, "completed %u sects req (%d)", -+ blk_rq_sectors(rq), sync); -+ -+ bfq_update_hw_tag(bfqd); -+ -+ WARN_ON(!bfqd->rq_in_driver); -+ WARN_ON(!bfqq->dispatched); -+ bfqd->rq_in_driver--; -+ bfqq->dispatched--; -+ -+ if (bfq_bfqq_sync(bfqq)) -+ bfqd->sync_flight--; -+ -+ if (sync) -+ RQ_BIC(rq)->ttime.last_end_request = jiffies; -+ -+ /* -+ * The computation of softrt_next_start was scheduled for the next -+ * request completion: it is now time to compute it. -+ */ -+ if (bfq_bfqq_softrt_update(bfqq) && RB_EMPTY_ROOT(&bfqq->sort_list)) -+ bfqq->soft_rt_next_start = -+ bfq_bfqq_softrt_next_start(bfqd, bfqq); -+ -+ /* -+ * If this is the in-service queue, check if it needs to be expired, -+ * or if we want to idle in case it has no pending requests. -+ */ -+ if (bfqd->in_service_queue == bfqq) { -+ if (bfq_bfqq_budget_new(bfqq)) -+ bfq_set_budget_timeout(bfqd); -+ -+ if (bfq_bfqq_must_idle(bfqq)) { -+ bfq_arm_slice_timer(bfqd); -+ goto out; -+ } else if (bfq_may_expire_for_budg_timeout(bfqq)) -+ bfq_bfqq_expire(bfqd, bfqq, 0, BFQ_BFQQ_BUDGET_TIMEOUT); -+ else if (RB_EMPTY_ROOT(&bfqq->sort_list) && -+ (bfqq->dispatched == 0 || -+ !bfq_bfqq_must_not_expire(bfqq))) -+ bfq_bfqq_expire(bfqd, bfqq, 0, -+ BFQ_BFQQ_NO_MORE_REQUESTS); -+ } -+ -+ if (!bfqd->rq_in_driver) -+ bfq_schedule_dispatch(bfqd); -+ -+out: -+ return; -+} -+ -+static inline int __bfq_may_queue(struct bfq_queue *bfqq) -+{ -+ if (bfq_bfqq_wait_request(bfqq) && bfq_bfqq_must_alloc(bfqq)) { -+ bfq_clear_bfqq_must_alloc(bfqq); -+ return ELV_MQUEUE_MUST; -+ } -+ -+ return ELV_MQUEUE_MAY; -+} -+ -+static int bfq_may_queue(struct request_queue *q, int rw) -+{ -+ struct bfq_data *bfqd = q->elevator->elevator_data; -+ struct task_struct *tsk = current; -+ struct bfq_io_cq *bic; -+ struct bfq_queue *bfqq; -+ -+ /* -+ * Don't force setup of a queue from here, as a call to may_queue -+ * does not necessarily imply that a request actually will be queued. -+ * So just lookup a possibly existing queue, or return 'may queue' -+ * if that fails. -+ */ -+ bic = bfq_bic_lookup(bfqd, tsk->io_context); -+ if (bic == NULL) -+ return ELV_MQUEUE_MAY; -+ -+ bfqq = bic_to_bfqq(bic, rw_is_sync(rw)); -+ if (bfqq != NULL) { -+ bfq_init_prio_data(bfqq, bic); -+ -+ return __bfq_may_queue(bfqq); -+ } -+ -+ return ELV_MQUEUE_MAY; -+} -+ -+/* -+ * Queue lock held here. -+ */ -+static void bfq_put_request(struct request *rq) -+{ -+ struct bfq_queue *bfqq = RQ_BFQQ(rq); -+ -+ if (bfqq != NULL) { -+ const int rw = rq_data_dir(rq); -+ -+ BUG_ON(!bfqq->allocated[rw]); -+ bfqq->allocated[rw]--; -+ -+ rq->elv.priv[0] = NULL; -+ rq->elv.priv[1] = NULL; -+ -+ bfq_log_bfqq(bfqq->bfqd, bfqq, "put_request %p, %d", -+ bfqq, atomic_read(&bfqq->ref)); -+ bfq_put_queue(bfqq); -+ } -+} -+ -+static struct bfq_queue * -+bfq_merge_bfqqs(struct bfq_data *bfqd, struct bfq_io_cq *bic, -+ struct bfq_queue *bfqq) -+{ -+ bfq_log_bfqq(bfqd, bfqq, "merging with queue %lu", -+ (long unsigned)bfqq->new_bfqq->pid); -+ bic_set_bfqq(bic, bfqq->new_bfqq, 1); -+ bfq_mark_bfqq_coop(bfqq->new_bfqq); -+ bfq_put_queue(bfqq); -+ return bic_to_bfqq(bic, 1); -+} -+ -+/* -+ * Returns NULL if a new bfqq should be allocated, or the old bfqq if this -+ * was the last process referring to said bfqq. -+ */ -+static struct bfq_queue * -+bfq_split_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq) -+{ -+ bfq_log_bfqq(bfqq->bfqd, bfqq, "splitting queue"); -+ if (bfqq_process_refs(bfqq) == 1) { -+ bfqq->pid = current->pid; -+ bfq_clear_bfqq_coop(bfqq); -+ bfq_clear_bfqq_split_coop(bfqq); -+ return bfqq; -+ } -+ -+ bic_set_bfqq(bic, NULL, 1); -+ -+ bfq_put_cooperator(bfqq); -+ -+ bfq_put_queue(bfqq); -+ return NULL; -+} -+ -+/* -+ * Allocate bfq data structures associated with this request. -+ */ -+static int bfq_set_request(struct request_queue *q, struct request *rq, -+ struct bio *bio, gfp_t gfp_mask) -+{ -+ struct bfq_data *bfqd = q->elevator->elevator_data; -+ struct bfq_io_cq *bic = icq_to_bic(rq->elv.icq); -+ const int rw = rq_data_dir(rq); -+ const int is_sync = rq_is_sync(rq); -+ struct bfq_queue *bfqq; -+ struct bfq_group *bfqg; -+ unsigned long flags; -+ -+ might_sleep_if(gfp_mask & __GFP_WAIT); -+ -+ bfq_changed_ioprio(bic); -+ -+ spin_lock_irqsave(q->queue_lock, flags); -+ -+ if (bic == NULL) -+ goto queue_fail; -+ -+ bfqg = bfq_bic_update_cgroup(bic); -+ -+new_queue: -+ bfqq = bic_to_bfqq(bic, is_sync); -+ if (bfqq == NULL || bfqq == &bfqd->oom_bfqq) { -+ bfqq = bfq_get_queue(bfqd, bfqg, is_sync, bic, gfp_mask); -+ bic_set_bfqq(bic, bfqq, is_sync); -+ } else { -+ /* -+ * If the queue was seeky for too long, break it apart. -+ */ -+ if (bfq_bfqq_coop(bfqq) && bfq_bfqq_split_coop(bfqq)) { -+ bfq_log_bfqq(bfqd, bfqq, "breaking apart bfqq"); -+ bfqq = bfq_split_bfqq(bic, bfqq); -+ if (!bfqq) -+ goto new_queue; -+ } -+ -+ /* -+ * Check to see if this queue is scheduled to merge with -+ * another closely cooperating queue. The merging of queues -+ * happens here as it must be done in process context. -+ * The reference on new_bfqq was taken in merge_bfqqs. -+ */ -+ if (bfqq->new_bfqq != NULL) -+ bfqq = bfq_merge_bfqqs(bfqd, bic, bfqq); -+ } -+ -+ bfqq->allocated[rw]++; -+ atomic_inc(&bfqq->ref); -+ bfq_log_bfqq(bfqd, bfqq, "set_request: bfqq %p, %d", bfqq, -+ atomic_read(&bfqq->ref)); -+ -+ rq->elv.priv[0] = bic; -+ rq->elv.priv[1] = bfqq; -+ -+ spin_unlock_irqrestore(q->queue_lock, flags); -+ -+ return 0; -+ -+queue_fail: -+ bfq_schedule_dispatch(bfqd); -+ spin_unlock_irqrestore(q->queue_lock, flags); -+ -+ return 1; -+} -+ -+static void bfq_kick_queue(struct work_struct *work) -+{ -+ struct bfq_data *bfqd = -+ container_of(work, struct bfq_data, unplug_work); -+ struct request_queue *q = bfqd->queue; -+ -+ spin_lock_irq(q->queue_lock); -+ __blk_run_queue(q); -+ spin_unlock_irq(q->queue_lock); -+} -+ -+/* -+ * Handler of the expiration of the timer running if the in-service queue -+ * is idling inside its time slice. -+ */ -+static void bfq_idle_slice_timer(unsigned long data) -+{ -+ struct bfq_data *bfqd = (struct bfq_data *)data; -+ struct bfq_queue *bfqq; -+ unsigned long flags; -+ enum bfqq_expiration reason; -+ -+ spin_lock_irqsave(bfqd->queue->queue_lock, flags); -+ -+ bfqq = bfqd->in_service_queue; -+ /* -+ * Theoretical race here: the in-service queue can be NULL or different -+ * from the queue that was idling if the timer handler spins on -+ * the queue_lock and a new request arrives for the current -+ * queue and there is a full dispatch cycle that changes the -+ * in-service queue. This can hardly happen, but in the worst case -+ * we just expire a queue too early. -+ */ -+ if (bfqq != NULL) { -+ bfq_log_bfqq(bfqd, bfqq, "slice_timer expired"); -+ if (bfq_bfqq_budget_timeout(bfqq)) -+ /* -+ * Also here the queue can be safely expired -+ * for budget timeout without wasting -+ * guarantees -+ */ -+ reason = BFQ_BFQQ_BUDGET_TIMEOUT; -+ else if (bfqq->queued[0] == 0 && bfqq->queued[1] == 0) -+ /* -+ * The queue may not be empty upon timer expiration, -+ * because we may not disable the timer when the first -+ * request of the in-service queue arrives during -+ * disk idling -+ */ -+ reason = BFQ_BFQQ_TOO_IDLE; -+ else -+ goto schedule_dispatch; -+ -+ bfq_bfqq_expire(bfqd, bfqq, 1, reason); -+ } -+ -+schedule_dispatch: -+ bfq_schedule_dispatch(bfqd); -+ -+ spin_unlock_irqrestore(bfqd->queue->queue_lock, flags); -+} -+ -+static void bfq_shutdown_timer_wq(struct bfq_data *bfqd) -+{ -+ del_timer_sync(&bfqd->idle_slice_timer); -+ cancel_work_sync(&bfqd->unplug_work); -+} -+ -+static inline void __bfq_put_async_bfqq(struct bfq_data *bfqd, -+ struct bfq_queue **bfqq_ptr) -+{ -+ struct bfq_group *root_group = bfqd->root_group; -+ struct bfq_queue *bfqq = *bfqq_ptr; -+ -+ bfq_log(bfqd, "put_async_bfqq: %p", bfqq); -+ if (bfqq != NULL) { -+ bfq_bfqq_move(bfqd, bfqq, &bfqq->entity, root_group); -+ bfq_log_bfqq(bfqd, bfqq, "put_async_bfqq: putting %p, %d", -+ bfqq, atomic_read(&bfqq->ref)); -+ bfq_put_queue(bfqq); -+ *bfqq_ptr = NULL; -+ } -+} -+ -+/* -+ * Release all the bfqg references to its async queues. If we are -+ * deallocating the group these queues may still contain requests, so -+ * we reparent them to the root cgroup (i.e., the only one that will -+ * exist for sure untill all the requests on a device are gone). -+ */ -+static void bfq_put_async_queues(struct bfq_data *bfqd, struct bfq_group *bfqg) -+{ -+ int i, j; -+ -+ for (i = 0; i < 2; i++) -+ for (j = 0; j < IOPRIO_BE_NR; j++) -+ __bfq_put_async_bfqq(bfqd, &bfqg->async_bfqq[i][j]); -+ -+ __bfq_put_async_bfqq(bfqd, &bfqg->async_idle_bfqq); -+} -+ -+static void bfq_exit_queue(struct elevator_queue *e) -+{ -+ struct bfq_data *bfqd = e->elevator_data; -+ struct request_queue *q = bfqd->queue; -+ struct bfq_queue *bfqq, *n; -+ -+ bfq_shutdown_timer_wq(bfqd); -+ -+ spin_lock_irq(q->queue_lock); -+ -+ BUG_ON(bfqd->in_service_queue != NULL); -+ list_for_each_entry_safe(bfqq, n, &bfqd->idle_list, bfqq_list) -+ bfq_deactivate_bfqq(bfqd, bfqq, 0); -+ -+ bfq_disconnect_groups(bfqd); -+ spin_unlock_irq(q->queue_lock); -+ -+ bfq_shutdown_timer_wq(bfqd); -+ -+ synchronize_rcu(); -+ -+ BUG_ON(timer_pending(&bfqd->idle_slice_timer)); -+ -+ bfq_free_root_group(bfqd); -+ kfree(bfqd); -+} -+ -+static int bfq_init_queue(struct request_queue *q) -+{ -+ struct bfq_group *bfqg; -+ struct bfq_data *bfqd; -+ -+ bfqd = kzalloc_node(sizeof(*bfqd), GFP_KERNEL, q->node); -+ if (bfqd == NULL) -+ return -ENOMEM; -+ -+ /* -+ * Our fallback bfqq if bfq_find_alloc_queue() runs into OOM issues. -+ * Grab a permanent reference to it, so that the normal code flow -+ * will not attempt to free it. -+ */ -+ bfq_init_bfqq(bfqd, &bfqd->oom_bfqq, 1, 0); -+ atomic_inc(&bfqd->oom_bfqq.ref); -+ -+ bfqd->queue = q; -+ q->elevator->elevator_data = bfqd; -+ -+ bfqg = bfq_alloc_root_group(bfqd, q->node); -+ if (bfqg == NULL) { -+ kfree(bfqd); -+ return -ENOMEM; -+ } -+ -+ bfqd->root_group = bfqg; -+ -+ init_timer(&bfqd->idle_slice_timer); -+ bfqd->idle_slice_timer.function = bfq_idle_slice_timer; -+ bfqd->idle_slice_timer.data = (unsigned long)bfqd; -+ -+ bfqd->rq_pos_tree = RB_ROOT; -+ -+ INIT_WORK(&bfqd->unplug_work, bfq_kick_queue); -+ -+ INIT_LIST_HEAD(&bfqd->active_list); -+ INIT_LIST_HEAD(&bfqd->idle_list); -+ -+ bfqd->hw_tag = -1; -+ -+ bfqd->bfq_max_budget = bfq_default_max_budget; -+ -+ bfqd->bfq_quantum = bfq_quantum; -+ bfqd->bfq_fifo_expire[0] = bfq_fifo_expire[0]; -+ bfqd->bfq_fifo_expire[1] = bfq_fifo_expire[1]; -+ bfqd->bfq_back_max = bfq_back_max; -+ bfqd->bfq_back_penalty = bfq_back_penalty; -+ bfqd->bfq_slice_idle = bfq_slice_idle; -+ bfqd->bfq_class_idle_last_service = 0; -+ bfqd->bfq_max_budget_async_rq = bfq_max_budget_async_rq; -+ bfqd->bfq_timeout[BLK_RW_ASYNC] = bfq_timeout_async; -+ bfqd->bfq_timeout[BLK_RW_SYNC] = bfq_timeout_sync; -+ -+ bfqd->low_latency = true; -+ -+ bfqd->bfq_raising_coeff = 20; -+ bfqd->bfq_raising_rt_max_time = msecs_to_jiffies(300); -+ bfqd->bfq_raising_max_time = 0; -+ bfqd->bfq_raising_min_idle_time = msecs_to_jiffies(2000); -+ bfqd->bfq_raising_min_inter_arr_async = msecs_to_jiffies(500); -+ bfqd->bfq_raising_max_softrt_rate = 7000; /* -+ * Approximate rate required -+ * to playback or record a -+ * high-definition compressed -+ * video. -+ */ -+ bfqd->raised_busy_queues = 0; -+ -+ /* Initially estimate the device's peak rate as the reference rate */ -+ if (blk_queue_nonrot(bfqd->queue)) { -+ bfqd->RT_prod = R_nonrot * T_nonrot; -+ bfqd->peak_rate = R_nonrot; -+ } else { -+ bfqd->RT_prod = R_rot * T_rot; -+ bfqd->peak_rate = R_rot; -+ } -+ -+ return 0; -+} -+ -+static void bfq_slab_kill(void) -+{ -+ if (bfq_pool != NULL) -+ kmem_cache_destroy(bfq_pool); -+} -+ -+static int __init bfq_slab_setup(void) -+{ -+ bfq_pool = KMEM_CACHE(bfq_queue, 0); -+ if (bfq_pool == NULL) -+ return -ENOMEM; -+ return 0; -+} -+ -+static ssize_t bfq_var_show(unsigned int var, char *page) -+{ -+ return sprintf(page, "%d\n", var); -+} -+ -+static ssize_t bfq_var_store(unsigned long *var, const char *page, size_t count) -+{ -+ unsigned long new_val; -+ int ret = kstrtoul(page, 10, &new_val); -+ -+ if (ret == 0) -+ *var = new_val; -+ -+ return count; -+} -+ -+static ssize_t bfq_raising_max_time_show(struct elevator_queue *e, char *page) -+{ -+ struct bfq_data *bfqd = e->elevator_data; -+ return sprintf(page, "%d\n", bfqd->bfq_raising_max_time > 0 ? -+ jiffies_to_msecs(bfqd->bfq_raising_max_time) : -+ jiffies_to_msecs(bfq_wrais_duration(bfqd))); -+} -+ -+static ssize_t bfq_weights_show(struct elevator_queue *e, char *page) -+{ -+ struct bfq_queue *bfqq; -+ struct bfq_data *bfqd = e->elevator_data; -+ ssize_t num_char = 0; -+ -+ num_char += sprintf(page + num_char, "Tot reqs queued %d\n\n", -+ bfqd->queued); -+ -+ spin_lock_irq(bfqd->queue->queue_lock); -+ -+ num_char += sprintf(page + num_char, "Active:\n"); -+ list_for_each_entry(bfqq, &bfqd->active_list, bfqq_list) { -+ num_char += sprintf(page + num_char, -+ "pid%d: weight %hu, nr_queued %d %d," -+ " dur %d/%u\n", -+ bfqq->pid, -+ bfqq->entity.weight, -+ bfqq->queued[0], -+ bfqq->queued[1], -+ jiffies_to_msecs(jiffies - -+ bfqq->last_rais_start_finish), -+ jiffies_to_msecs(bfqq->raising_cur_max_time)); -+ } -+ -+ num_char += sprintf(page + num_char, "Idle:\n"); -+ list_for_each_entry(bfqq, &bfqd->idle_list, bfqq_list) { -+ num_char += sprintf(page + num_char, -+ "pid%d: weight %hu, dur %d/%u\n", -+ bfqq->pid, -+ bfqq->entity.weight, -+ jiffies_to_msecs(jiffies - -+ bfqq->last_rais_start_finish), -+ jiffies_to_msecs(bfqq->raising_cur_max_time)); -+ } -+ -+ spin_unlock_irq(bfqd->queue->queue_lock); -+ -+ return num_char; -+} -+ -+#define SHOW_FUNCTION(__FUNC, __VAR, __CONV) \ -+static ssize_t __FUNC(struct elevator_queue *e, char *page) \ -+{ \ -+ struct bfq_data *bfqd = e->elevator_data; \ -+ unsigned int __data = __VAR; \ -+ if (__CONV) \ -+ __data = jiffies_to_msecs(__data); \ -+ return bfq_var_show(__data, (page)); \ -+} -+SHOW_FUNCTION(bfq_quantum_show, bfqd->bfq_quantum, 0); -+SHOW_FUNCTION(bfq_fifo_expire_sync_show, bfqd->bfq_fifo_expire[1], 1); -+SHOW_FUNCTION(bfq_fifo_expire_async_show, bfqd->bfq_fifo_expire[0], 1); -+SHOW_FUNCTION(bfq_back_seek_max_show, bfqd->bfq_back_max, 0); -+SHOW_FUNCTION(bfq_back_seek_penalty_show, bfqd->bfq_back_penalty, 0); -+SHOW_FUNCTION(bfq_slice_idle_show, bfqd->bfq_slice_idle, 1); -+SHOW_FUNCTION(bfq_max_budget_show, bfqd->bfq_user_max_budget, 0); -+SHOW_FUNCTION(bfq_max_budget_async_rq_show, bfqd->bfq_max_budget_async_rq, 0); -+SHOW_FUNCTION(bfq_timeout_sync_show, bfqd->bfq_timeout[BLK_RW_SYNC], 1); -+SHOW_FUNCTION(bfq_timeout_async_show, bfqd->bfq_timeout[BLK_RW_ASYNC], 1); -+SHOW_FUNCTION(bfq_low_latency_show, bfqd->low_latency, 0); -+SHOW_FUNCTION(bfq_raising_coeff_show, bfqd->bfq_raising_coeff, 0); -+SHOW_FUNCTION(bfq_raising_rt_max_time_show, bfqd->bfq_raising_rt_max_time, 1); -+SHOW_FUNCTION(bfq_raising_min_idle_time_show, bfqd->bfq_raising_min_idle_time, -+ 1); -+SHOW_FUNCTION(bfq_raising_min_inter_arr_async_show, -+ bfqd->bfq_raising_min_inter_arr_async, -+ 1); -+SHOW_FUNCTION(bfq_raising_max_softrt_rate_show, -+ bfqd->bfq_raising_max_softrt_rate, 0); -+#undef SHOW_FUNCTION -+ -+#define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV) \ -+static ssize_t \ -+__FUNC(struct elevator_queue *e, const char *page, size_t count) \ -+{ \ -+ struct bfq_data *bfqd = e->elevator_data; \ -+ unsigned long uninitialized_var(__data); \ -+ int ret = bfq_var_store(&__data, (page), count); \ -+ if (__data < (MIN)) \ -+ __data = (MIN); \ -+ else if (__data > (MAX)) \ -+ __data = (MAX); \ -+ if (__CONV) \ -+ *(__PTR) = msecs_to_jiffies(__data); \ -+ else \ -+ *(__PTR) = __data; \ -+ return ret; \ -+} -+STORE_FUNCTION(bfq_quantum_store, &bfqd->bfq_quantum, 1, INT_MAX, 0); -+STORE_FUNCTION(bfq_fifo_expire_sync_store, &bfqd->bfq_fifo_expire[1], 1, -+ INT_MAX, 1); -+STORE_FUNCTION(bfq_fifo_expire_async_store, &bfqd->bfq_fifo_expire[0], 1, -+ INT_MAX, 1); -+STORE_FUNCTION(bfq_back_seek_max_store, &bfqd->bfq_back_max, 0, INT_MAX, 0); -+STORE_FUNCTION(bfq_back_seek_penalty_store, &bfqd->bfq_back_penalty, 1, -+ INT_MAX, 0); -+STORE_FUNCTION(bfq_slice_idle_store, &bfqd->bfq_slice_idle, 0, INT_MAX, 1); -+STORE_FUNCTION(bfq_max_budget_async_rq_store, &bfqd->bfq_max_budget_async_rq, -+ 1, INT_MAX, 0); -+STORE_FUNCTION(bfq_timeout_async_store, &bfqd->bfq_timeout[BLK_RW_ASYNC], 0, -+ INT_MAX, 1); -+STORE_FUNCTION(bfq_raising_coeff_store, &bfqd->bfq_raising_coeff, 1, -+ INT_MAX, 0); -+STORE_FUNCTION(bfq_raising_max_time_store, &bfqd->bfq_raising_max_time, 0, -+ INT_MAX, 1); -+STORE_FUNCTION(bfq_raising_rt_max_time_store, &bfqd->bfq_raising_rt_max_time, 0, -+ INT_MAX, 1); -+STORE_FUNCTION(bfq_raising_min_idle_time_store, -+ &bfqd->bfq_raising_min_idle_time, 0, INT_MAX, 1); -+STORE_FUNCTION(bfq_raising_min_inter_arr_async_store, -+ &bfqd->bfq_raising_min_inter_arr_async, 0, INT_MAX, 1); -+STORE_FUNCTION(bfq_raising_max_softrt_rate_store, -+ &bfqd->bfq_raising_max_softrt_rate, 0, INT_MAX, 0); -+#undef STORE_FUNCTION -+ -+/* do nothing for the moment */ -+static ssize_t bfq_weights_store(struct elevator_queue *e, -+ const char *page, size_t count) -+{ -+ return count; -+} -+ -+static inline unsigned long bfq_estimated_max_budget(struct bfq_data *bfqd) -+{ -+ u64 timeout = jiffies_to_msecs(bfqd->bfq_timeout[BLK_RW_SYNC]); -+ -+ if (bfqd->peak_rate_samples >= BFQ_PEAK_RATE_SAMPLES) -+ return bfq_calc_max_budget(bfqd->peak_rate, timeout); -+ else -+ return bfq_default_max_budget; -+} -+ -+static ssize_t bfq_max_budget_store(struct elevator_queue *e, -+ const char *page, size_t count) -+{ -+ struct bfq_data *bfqd = e->elevator_data; -+ unsigned long uninitialized_var(__data); -+ int ret = bfq_var_store(&__data, (page), count); -+ -+ if (__data == 0) -+ bfqd->bfq_max_budget = bfq_estimated_max_budget(bfqd); -+ else { -+ if (__data > INT_MAX) -+ __data = INT_MAX; -+ bfqd->bfq_max_budget = __data; -+ } -+ -+ bfqd->bfq_user_max_budget = __data; -+ -+ return ret; -+} -+ -+static ssize_t bfq_timeout_sync_store(struct elevator_queue *e, -+ const char *page, size_t count) -+{ -+ struct bfq_data *bfqd = e->elevator_data; -+ unsigned long uninitialized_var(__data); -+ int ret = bfq_var_store(&__data, (page), count); -+ -+ if (__data < 1) -+ __data = 1; -+ else if (__data > INT_MAX) -+ __data = INT_MAX; -+ -+ bfqd->bfq_timeout[BLK_RW_SYNC] = msecs_to_jiffies(__data); -+ if (bfqd->bfq_user_max_budget == 0) -+ bfqd->bfq_max_budget = bfq_estimated_max_budget(bfqd); -+ -+ return ret; -+} -+ -+static ssize_t bfq_low_latency_store(struct elevator_queue *e, -+ const char *page, size_t count) -+{ -+ struct bfq_data *bfqd = e->elevator_data; -+ unsigned long uninitialized_var(__data); -+ int ret = bfq_var_store(&__data, (page), count); -+ -+ if (__data > 1) -+ __data = 1; -+ if (__data == 0 && bfqd->low_latency != 0) -+ bfq_end_raising(bfqd); -+ bfqd->low_latency = __data; -+ -+ return ret; -+} -+ -+#define BFQ_ATTR(name) \ -+ __ATTR(name, S_IRUGO|S_IWUSR, bfq_##name##_show, bfq_##name##_store) -+ -+static struct elv_fs_entry bfq_attrs[] = { -+ BFQ_ATTR(quantum), -+ BFQ_ATTR(fifo_expire_sync), -+ BFQ_ATTR(fifo_expire_async), -+ BFQ_ATTR(back_seek_max), -+ BFQ_ATTR(back_seek_penalty), -+ BFQ_ATTR(slice_idle), -+ BFQ_ATTR(max_budget), -+ BFQ_ATTR(max_budget_async_rq), -+ BFQ_ATTR(timeout_sync), -+ BFQ_ATTR(timeout_async), -+ BFQ_ATTR(low_latency), -+ BFQ_ATTR(raising_coeff), -+ BFQ_ATTR(raising_max_time), -+ BFQ_ATTR(raising_rt_max_time), -+ BFQ_ATTR(raising_min_idle_time), -+ BFQ_ATTR(raising_min_inter_arr_async), -+ BFQ_ATTR(raising_max_softrt_rate), -+ BFQ_ATTR(weights), -+ __ATTR_NULL -+}; -+ -+static struct elevator_type iosched_bfq = { -+ .ops = { -+ .elevator_merge_fn = bfq_merge, -+ .elevator_merged_fn = bfq_merged_request, -+ .elevator_merge_req_fn = bfq_merged_requests, -+ .elevator_allow_merge_fn = bfq_allow_merge, -+ .elevator_dispatch_fn = bfq_dispatch_requests, -+ .elevator_add_req_fn = bfq_insert_request, -+ .elevator_activate_req_fn = bfq_activate_request, -+ .elevator_deactivate_req_fn = bfq_deactivate_request, -+ .elevator_completed_req_fn = bfq_completed_request, -+ .elevator_former_req_fn = elv_rb_former_request, -+ .elevator_latter_req_fn = elv_rb_latter_request, -+ .elevator_init_icq_fn = bfq_init_icq, -+ .elevator_exit_icq_fn = bfq_exit_icq, -+ .elevator_set_req_fn = bfq_set_request, -+ .elevator_put_req_fn = bfq_put_request, -+ .elevator_may_queue_fn = bfq_may_queue, -+ .elevator_init_fn = bfq_init_queue, -+ .elevator_exit_fn = bfq_exit_queue, -+ }, -+ .icq_size = sizeof(struct bfq_io_cq), -+ .icq_align = __alignof__(struct bfq_io_cq), -+ .elevator_attrs = bfq_attrs, -+ .elevator_name = "bfq", -+ .elevator_owner = THIS_MODULE, -+}; -+ -+static int __init bfq_init(void) -+{ -+ /* -+ * Can be 0 on HZ < 1000 setups. -+ */ -+ if (bfq_slice_idle == 0) -+ bfq_slice_idle = 1; -+ -+ if (bfq_timeout_async == 0) -+ bfq_timeout_async = 1; -+ -+ if (bfq_slab_setup()) -+ return -ENOMEM; -+ -+ elv_register(&iosched_bfq); -+ printk(KERN_INFO "BFQ I/O-scheduler version: v7"); -+ -+ return 0; -+} -+ -+static void __exit bfq_exit(void) -+{ -+ elv_unregister(&iosched_bfq); -+ bfq_slab_kill(); -+} -+ -+module_init(bfq_init); -+module_exit(bfq_exit); -+ -+MODULE_AUTHOR("Fabio Checconi, Paolo Valente"); -+MODULE_LICENSE("GPL"); -+MODULE_DESCRIPTION("Budget Fair Queueing IO scheduler"); -diff --git a/block/bfq-sched.c b/block/bfq-sched.c -new file mode 100644 -index 0000000..30df81c ---- /dev/null -+++ b/block/bfq-sched.c -@@ -0,0 +1,1077 @@ -+/* -+ * BFQ: Hierarchical B-WF2Q+ scheduler. -+ * -+ * Based on ideas and code from CFQ: -+ * Copyright (C) 2003 Jens Axboe -+ * -+ * Copyright (C) 2008 Fabio Checconi -+ * Paolo Valente -+ * -+ * Copyright (C) 2010 Paolo Valente -+ */ -+ -+#ifdef CONFIG_CGROUP_BFQIO -+#define for_each_entity(entity) \ -+ for (; entity != NULL; entity = entity->parent) -+ -+#define for_each_entity_safe(entity, parent) \ -+ for (; entity && ({ parent = entity->parent; 1; }); entity = parent) -+ -+static struct bfq_entity *bfq_lookup_next_entity(struct bfq_sched_data *sd, -+ int extract, -+ struct bfq_data *bfqd); -+ -+static inline void bfq_update_budget(struct bfq_entity *next_active) -+{ -+ struct bfq_entity *bfqg_entity; -+ struct bfq_group *bfqg; -+ struct bfq_sched_data *group_sd; -+ -+ BUG_ON(next_active == NULL); -+ -+ group_sd = next_active->sched_data; -+ -+ bfqg = container_of(group_sd, struct bfq_group, sched_data); -+ /* -+ * bfq_group's my_entity field is not NULL only if the group -+ * is not the root group. We must not touch the root entity -+ * as it must never become an active entity. -+ */ -+ bfqg_entity = bfqg->my_entity; -+ if (bfqg_entity != NULL) -+ bfqg_entity->budget = next_active->budget; -+} -+ -+static int bfq_update_next_active(struct bfq_sched_data *sd) -+{ -+ struct bfq_entity *next_active; -+ -+ if (sd->active_entity != NULL) -+ /* will update/requeue at the end of service */ -+ return 0; -+ -+ /* -+ * NOTE: this can be improved in many ways, such as returning -+ * 1 (and thus propagating upwards the update) only when the -+ * budget changes, or caching the bfqq that will be scheduled -+ * next from this subtree. By now we worry more about -+ * correctness than about performance... -+ */ -+ next_active = bfq_lookup_next_entity(sd, 0, NULL); -+ sd->next_active = next_active; -+ -+ if (next_active != NULL) -+ bfq_update_budget(next_active); -+ -+ return 1; -+} -+ -+static inline void bfq_check_next_active(struct bfq_sched_data *sd, -+ struct bfq_entity *entity) -+{ -+ BUG_ON(sd->next_active != entity); -+} -+#else -+#define for_each_entity(entity) \ -+ for (; entity != NULL; entity = NULL) -+ -+#define for_each_entity_safe(entity, parent) \ -+ for (parent = NULL; entity != NULL; entity = parent) -+ -+static inline int bfq_update_next_active(struct bfq_sched_data *sd) -+{ -+ return 0; -+} -+ -+static inline void bfq_check_next_active(struct bfq_sched_data *sd, -+ struct bfq_entity *entity) -+{ -+} -+ -+static inline void bfq_update_budget(struct bfq_entity *next_active) -+{ -+} -+#endif -+ -+/* -+ * Shift for timestamp calculations. This actually limits the maximum -+ * service allowed in one timestamp delta (small shift values increase it), -+ * the maximum total weight that can be used for the queues in the system -+ * (big shift values increase it), and the period of virtual time wraparounds. -+ */ -+#define WFQ_SERVICE_SHIFT 22 -+ -+/** -+ * bfq_gt - compare two timestamps. -+ * @a: first ts. -+ * @b: second ts. -+ * -+ * Return @a > @b, dealing with wrapping correctly. -+ */ -+static inline int bfq_gt(u64 a, u64 b) -+{ -+ return (s64)(a - b) > 0; -+} -+ -+static inline struct bfq_queue *bfq_entity_to_bfqq(struct bfq_entity *entity) -+{ -+ struct bfq_queue *bfqq = NULL; -+ -+ BUG_ON(entity == NULL); -+ -+ if (entity->my_sched_data == NULL) -+ bfqq = container_of(entity, struct bfq_queue, entity); -+ -+ return bfqq; -+} -+ -+ -+/** -+ * bfq_delta - map service into the virtual time domain. -+ * @service: amount of service. -+ * @weight: scale factor (weight of an entity or weight sum). -+ */ -+static inline u64 bfq_delta(unsigned long service, -+ unsigned long weight) -+{ -+ u64 d = (u64)service << WFQ_SERVICE_SHIFT; -+ -+ do_div(d, weight); -+ return d; -+} -+ -+/** -+ * bfq_calc_finish - assign the finish time to an entity. -+ * @entity: the entity to act upon. -+ * @service: the service to be charged to the entity. -+ */ -+static inline void bfq_calc_finish(struct bfq_entity *entity, -+ unsigned long service) -+{ -+ struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); -+ -+ BUG_ON(entity->weight == 0); -+ -+ entity->finish = entity->start + -+ bfq_delta(service, entity->weight); -+ -+ if (bfqq != NULL) { -+ bfq_log_bfqq(bfqq->bfqd, bfqq, -+ "calc_finish: serv %lu, w %d", -+ service, entity->weight); -+ bfq_log_bfqq(bfqq->bfqd, bfqq, -+ "calc_finish: start %llu, finish %llu, delta %llu", -+ entity->start, entity->finish, -+ bfq_delta(service, entity->weight)); -+ } -+} -+ -+/** -+ * bfq_entity_of - get an entity from a node. -+ * @node: the node field of the entity. -+ * -+ * Convert a node pointer to the relative entity. This is used only -+ * to simplify the logic of some functions and not as the generic -+ * conversion mechanism because, e.g., in the tree walking functions, -+ * the check for a %NULL value would be redundant. -+ */ -+static inline struct bfq_entity *bfq_entity_of(struct rb_node *node) -+{ -+ struct bfq_entity *entity = NULL; -+ -+ if (node != NULL) -+ entity = rb_entry(node, struct bfq_entity, rb_node); -+ -+ return entity; -+} -+ -+/** -+ * bfq_extract - remove an entity from a tree. -+ * @root: the tree root. -+ * @entity: the entity to remove. -+ */ -+static inline void bfq_extract(struct rb_root *root, -+ struct bfq_entity *entity) -+{ -+ BUG_ON(entity->tree != root); -+ -+ entity->tree = NULL; -+ rb_erase(&entity->rb_node, root); -+} -+ -+/** -+ * bfq_idle_extract - extract an entity from the idle tree. -+ * @st: the service tree of the owning @entity. -+ * @entity: the entity being removed. -+ */ -+static void bfq_idle_extract(struct bfq_service_tree *st, -+ struct bfq_entity *entity) -+{ -+ struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); -+ struct rb_node *next; -+ -+ BUG_ON(entity->tree != &st->idle); -+ -+ if (entity == st->first_idle) { -+ next = rb_next(&entity->rb_node); -+ st->first_idle = bfq_entity_of(next); -+ } -+ -+ if (entity == st->last_idle) { -+ next = rb_prev(&entity->rb_node); -+ st->last_idle = bfq_entity_of(next); -+ } -+ -+ bfq_extract(&st->idle, entity); -+ -+ if (bfqq != NULL) -+ list_del(&bfqq->bfqq_list); -+} -+ -+/** -+ * bfq_insert - generic tree insertion. -+ * @root: tree root. -+ * @entity: entity to insert. -+ * -+ * This is used for the idle and the active tree, since they are both -+ * ordered by finish time. -+ */ -+static void bfq_insert(struct rb_root *root, struct bfq_entity *entity) -+{ -+ struct bfq_entity *entry; -+ struct rb_node **node = &root->rb_node; -+ struct rb_node *parent = NULL; -+ -+ BUG_ON(entity->tree != NULL); -+ -+ while (*node != NULL) { -+ parent = *node; -+ entry = rb_entry(parent, struct bfq_entity, rb_node); -+ -+ if (bfq_gt(entry->finish, entity->finish)) -+ node = &parent->rb_left; -+ else -+ node = &parent->rb_right; -+ } -+ -+ rb_link_node(&entity->rb_node, parent, node); -+ rb_insert_color(&entity->rb_node, root); -+ -+ entity->tree = root; -+} -+ -+/** -+ * bfq_update_min - update the min_start field of a entity. -+ * @entity: the entity to update. -+ * @node: one of its children. -+ * -+ * This function is called when @entity may store an invalid value for -+ * min_start due to updates to the active tree. The function assumes -+ * that the subtree rooted at @node (which may be its left or its right -+ * child) has a valid min_start value. -+ */ -+static inline void bfq_update_min(struct bfq_entity *entity, -+ struct rb_node *node) -+{ -+ struct bfq_entity *child; -+ -+ if (node != NULL) { -+ child = rb_entry(node, struct bfq_entity, rb_node); -+ if (bfq_gt(entity->min_start, child->min_start)) -+ entity->min_start = child->min_start; -+ } -+} -+ -+/** -+ * bfq_update_active_node - recalculate min_start. -+ * @node: the node to update. -+ * -+ * @node may have changed position or one of its children may have moved, -+ * this function updates its min_start value. The left and right subtrees -+ * are assumed to hold a correct min_start value. -+ */ -+static inline void bfq_update_active_node(struct rb_node *node) -+{ -+ struct bfq_entity *entity = rb_entry(node, struct bfq_entity, rb_node); -+ -+ entity->min_start = entity->start; -+ bfq_update_min(entity, node->rb_right); -+ bfq_update_min(entity, node->rb_left); -+} -+ -+/** -+ * bfq_update_active_tree - update min_start for the whole active tree. -+ * @node: the starting node. -+ * -+ * @node must be the deepest modified node after an update. This function -+ * updates its min_start using the values held by its children, assuming -+ * that they did not change, and then updates all the nodes that may have -+ * changed in the path to the root. The only nodes that may have changed -+ * are the ones in the path or their siblings. -+ */ -+static void bfq_update_active_tree(struct rb_node *node) -+{ -+ struct rb_node *parent; -+ -+up: -+ bfq_update_active_node(node); -+ -+ parent = rb_parent(node); -+ if (parent == NULL) -+ return; -+ -+ if (node == parent->rb_left && parent->rb_right != NULL) -+ bfq_update_active_node(parent->rb_right); -+ else if (parent->rb_left != NULL) -+ bfq_update_active_node(parent->rb_left); -+ -+ node = parent; -+ goto up; -+} -+ -+/** -+ * bfq_active_insert - insert an entity in the active tree of its group/device. -+ * @st: the service tree of the entity. -+ * @entity: the entity being inserted. -+ * -+ * The active tree is ordered by finish time, but an extra key is kept -+ * per each node, containing the minimum value for the start times of -+ * its children (and the node itself), so it's possible to search for -+ * the eligible node with the lowest finish time in logarithmic time. -+ */ -+static void bfq_active_insert(struct bfq_service_tree *st, -+ struct bfq_entity *entity) -+{ -+ struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); -+ struct rb_node *node = &entity->rb_node; -+ -+ bfq_insert(&st->active, entity); -+ -+ if (node->rb_left != NULL) -+ node = node->rb_left; -+ else if (node->rb_right != NULL) -+ node = node->rb_right; -+ -+ bfq_update_active_tree(node); -+ -+ if (bfqq != NULL) -+ list_add(&bfqq->bfqq_list, &bfqq->bfqd->active_list); -+} -+ -+/** -+ * bfq_ioprio_to_weight - calc a weight from an ioprio. -+ * @ioprio: the ioprio value to convert. -+ */ -+static unsigned short bfq_ioprio_to_weight(int ioprio) -+{ -+ WARN_ON(ioprio < 0 || ioprio >= IOPRIO_BE_NR); -+ return IOPRIO_BE_NR - ioprio; -+} -+ -+/** -+ * bfq_weight_to_ioprio - calc an ioprio from a weight. -+ * @weight: the weight value to convert. -+ * -+ * To preserve as mush as possible the old only-ioprio user interface, -+ * 0 is used as an escape ioprio value for weights (numerically) equal or -+ * larger than IOPRIO_BE_NR -+ */ -+static unsigned short bfq_weight_to_ioprio(int weight) -+{ -+ WARN_ON(weight < BFQ_MIN_WEIGHT || weight > BFQ_MAX_WEIGHT); -+ return IOPRIO_BE_NR - weight < 0 ? 0 : IOPRIO_BE_NR - weight; -+} -+ -+static inline void bfq_get_entity(struct bfq_entity *entity) -+{ -+ struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); -+ struct bfq_sched_data *sd; -+ -+ if (bfqq != NULL) { -+ sd = entity->sched_data; -+ atomic_inc(&bfqq->ref); -+ bfq_log_bfqq(bfqq->bfqd, bfqq, "get_entity: %p %d", -+ bfqq, atomic_read(&bfqq->ref)); -+ } -+} -+ -+/** -+ * bfq_find_deepest - find the deepest node that an extraction can modify. -+ * @node: the node being removed. -+ * -+ * Do the first step of an extraction in an rb tree, looking for the -+ * node that will replace @node, and returning the deepest node that -+ * the following modifications to the tree can touch. If @node is the -+ * last node in the tree return %NULL. -+ */ -+static struct rb_node *bfq_find_deepest(struct rb_node *node) -+{ -+ struct rb_node *deepest; -+ -+ if (node->rb_right == NULL && node->rb_left == NULL) -+ deepest = rb_parent(node); -+ else if (node->rb_right == NULL) -+ deepest = node->rb_left; -+ else if (node->rb_left == NULL) -+ deepest = node->rb_right; -+ else { -+ deepest = rb_next(node); -+ if (deepest->rb_right != NULL) -+ deepest = deepest->rb_right; -+ else if (rb_parent(deepest) != node) -+ deepest = rb_parent(deepest); -+ } -+ -+ return deepest; -+} -+ -+/** -+ * bfq_active_extract - remove an entity from the active tree. -+ * @st: the service_tree containing the tree. -+ * @entity: the entity being removed. -+ */ -+static void bfq_active_extract(struct bfq_service_tree *st, -+ struct bfq_entity *entity) -+{ -+ struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); -+ struct rb_node *node; -+ -+ node = bfq_find_deepest(&entity->rb_node); -+ bfq_extract(&st->active, entity); -+ -+ if (node != NULL) -+ bfq_update_active_tree(node); -+ -+ if (bfqq != NULL) -+ list_del(&bfqq->bfqq_list); -+} -+ -+/** -+ * bfq_idle_insert - insert an entity into the idle tree. -+ * @st: the service tree containing the tree. -+ * @entity: the entity to insert. -+ */ -+static void bfq_idle_insert(struct bfq_service_tree *st, -+ struct bfq_entity *entity) -+{ -+ struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); -+ struct bfq_entity *first_idle = st->first_idle; -+ struct bfq_entity *last_idle = st->last_idle; -+ -+ if (first_idle == NULL || bfq_gt(first_idle->finish, entity->finish)) -+ st->first_idle = entity; -+ if (last_idle == NULL || bfq_gt(entity->finish, last_idle->finish)) -+ st->last_idle = entity; -+ -+ bfq_insert(&st->idle, entity); -+ -+ if (bfqq != NULL) -+ list_add(&bfqq->bfqq_list, &bfqq->bfqd->idle_list); -+} -+ -+/** -+ * bfq_forget_entity - remove an entity from the wfq trees. -+ * @st: the service tree. -+ * @entity: the entity being removed. -+ * -+ * Update the device status and forget everything about @entity, putting -+ * the device reference to it, if it is a queue. Entities belonging to -+ * groups are not refcounted. -+ */ -+static void bfq_forget_entity(struct bfq_service_tree *st, -+ struct bfq_entity *entity) -+{ -+ struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); -+ struct bfq_sched_data *sd; -+ -+ BUG_ON(!entity->on_st); -+ -+ entity->on_st = 0; -+ st->wsum -= entity->weight; -+ if (bfqq != NULL) { -+ sd = entity->sched_data; -+ bfq_log_bfqq(bfqq->bfqd, bfqq, "forget_entity: %p %d", -+ bfqq, atomic_read(&bfqq->ref)); -+ bfq_put_queue(bfqq); -+ } -+} -+ -+/** -+ * bfq_put_idle_entity - release the idle tree ref of an entity. -+ * @st: service tree for the entity. -+ * @entity: the entity being released. -+ */ -+static void bfq_put_idle_entity(struct bfq_service_tree *st, -+ struct bfq_entity *entity) -+{ -+ bfq_idle_extract(st, entity); -+ bfq_forget_entity(st, entity); -+} -+ -+/** -+ * bfq_forget_idle - update the idle tree if necessary. -+ * @st: the service tree to act upon. -+ * -+ * To preserve the global O(log N) complexity we only remove one entry here; -+ * as the idle tree will not grow indefinitely this can be done safely. -+ */ -+static void bfq_forget_idle(struct bfq_service_tree *st) -+{ -+ struct bfq_entity *first_idle = st->first_idle; -+ struct bfq_entity *last_idle = st->last_idle; -+ -+ if (RB_EMPTY_ROOT(&st->active) && last_idle != NULL && -+ !bfq_gt(last_idle->finish, st->vtime)) { -+ /* -+ * Forget the whole idle tree, increasing the vtime past -+ * the last finish time of idle entities. -+ */ -+ st->vtime = last_idle->finish; -+ } -+ -+ if (first_idle != NULL && !bfq_gt(first_idle->finish, st->vtime)) -+ bfq_put_idle_entity(st, first_idle); -+} -+ -+static struct bfq_service_tree * -+__bfq_entity_update_weight_prio(struct bfq_service_tree *old_st, -+ struct bfq_entity *entity) -+{ -+ struct bfq_service_tree *new_st = old_st; -+ -+ if (entity->ioprio_changed) { -+ struct bfq_queue *bfqq = bfq_entity_to_bfqq(entity); -+ -+ BUG_ON(old_st->wsum < entity->weight); -+ old_st->wsum -= entity->weight; -+ -+ if (entity->new_weight != entity->orig_weight) { -+ entity->orig_weight = entity->new_weight; -+ entity->ioprio = -+ bfq_weight_to_ioprio(entity->orig_weight); -+ } else if (entity->new_ioprio != entity->ioprio) { -+ entity->ioprio = entity->new_ioprio; -+ entity->orig_weight = -+ bfq_ioprio_to_weight(entity->ioprio); -+ } else -+ entity->new_weight = entity->orig_weight = -+ bfq_ioprio_to_weight(entity->ioprio); -+ -+ entity->ioprio_class = entity->new_ioprio_class; -+ entity->ioprio_changed = 0; -+ -+ /* -+ * NOTE: here we may be changing the weight too early, -+ * this will cause unfairness. The correct approach -+ * would have required additional complexity to defer -+ * weight changes to the proper time instants (i.e., -+ * when entity->finish <= old_st->vtime). -+ */ -+ new_st = bfq_entity_service_tree(entity); -+ entity->weight = entity->orig_weight * -+ (bfqq != NULL ? bfqq->raising_coeff : 1); -+ new_st->wsum += entity->weight; -+ -+ if (new_st != old_st) -+ entity->start = new_st->vtime; -+ } -+ -+ return new_st; -+} -+ -+/** -+ * bfq_bfqq_served - update the scheduler status after selection for service. -+ * @bfqq: the queue being served. -+ * @served: bytes to transfer. -+ * -+ * NOTE: this can be optimized, as the timestamps of upper level entities -+ * are synchronized every time a new bfqq is selected for service. By now, -+ * we keep it to better check consistency. -+ */ -+static void bfq_bfqq_served(struct bfq_queue *bfqq, unsigned long served) -+{ -+ struct bfq_entity *entity = &bfqq->entity; -+ struct bfq_service_tree *st; -+ -+ for_each_entity(entity) { -+ st = bfq_entity_service_tree(entity); -+ -+ entity->service += served; -+ BUG_ON(entity->service > entity->budget); -+ BUG_ON(st->wsum == 0); -+ -+ st->vtime += bfq_delta(served, st->wsum); -+ bfq_forget_idle(st); -+ } -+ bfq_log_bfqq(bfqq->bfqd, bfqq, "bfqq_served %lu secs", served); -+} -+ -+/** -+ * bfq_bfqq_charge_full_budget - set the service to the entity budget. -+ * @bfqq: the queue that needs a service update. -+ * -+ * When it's not possible to be fair in the service domain, because -+ * a queue is not consuming its budget fast enough (the meaning of -+ * fast depends on the timeout parameter), we charge it a full -+ * budget. In this way we should obtain a sort of time-domain -+ * fairness among all the seeky/slow queues. -+ */ -+static inline void bfq_bfqq_charge_full_budget(struct bfq_queue *bfqq) -+{ -+ struct bfq_entity *entity = &bfqq->entity; -+ -+ bfq_log_bfqq(bfqq->bfqd, bfqq, "charge_full_budget"); -+ -+ bfq_bfqq_served(bfqq, entity->budget - entity->service); -+} -+ -+/** -+ * __bfq_activate_entity - activate an entity. -+ * @entity: the entity being activated. -+ * -+ * Called whenever an entity is activated, i.e., it is not active and one -+ * of its children receives a new request, or has to be reactivated due to -+ * budget exhaustion. It uses the current budget of the entity (and the -+ * service received if @entity is active) of the queue to calculate its -+ * timestamps. -+ */ -+static void __bfq_activate_entity(struct bfq_entity *entity) -+{ -+ struct bfq_sched_data *sd = entity->sched_data; -+ struct bfq_service_tree *st = bfq_entity_service_tree(entity); -+ -+ if (entity == sd->active_entity) { -+ BUG_ON(entity->tree != NULL); -+ /* -+ * If we are requeueing the current entity we have -+ * to take care of not charging to it service it has -+ * not received. -+ */ -+ bfq_calc_finish(entity, entity->service); -+ entity->start = entity->finish; -+ sd->active_entity = NULL; -+ } else if (entity->tree == &st->active) { -+ /* -+ * Requeueing an entity due to a change of some -+ * next_active entity below it. We reuse the old -+ * start time. -+ */ -+ bfq_active_extract(st, entity); -+ } else if (entity->tree == &st->idle) { -+ /* -+ * Must be on the idle tree, bfq_idle_extract() will -+ * check for that. -+ */ -+ bfq_idle_extract(st, entity); -+ entity->start = bfq_gt(st->vtime, entity->finish) ? -+ st->vtime : entity->finish; -+ } else { -+ /* -+ * The finish time of the entity may be invalid, and -+ * it is in the past for sure, otherwise the queue -+ * would have been on the idle tree. -+ */ -+ entity->start = st->vtime; -+ st->wsum += entity->weight; -+ bfq_get_entity(entity); -+ -+ BUG_ON(entity->on_st); -+ entity->on_st = 1; -+ } -+ -+ st = __bfq_entity_update_weight_prio(st, entity); -+ bfq_calc_finish(entity, entity->budget); -+ bfq_active_insert(st, entity); -+} -+ -+/** -+ * bfq_activate_entity - activate an entity and its ancestors if necessary. -+ * @entity: the entity to activate. -+ * -+ * Activate @entity and all the entities on the path from it to the root. -+ */ -+static void bfq_activate_entity(struct bfq_entity *entity) -+{ -+ struct bfq_sched_data *sd; -+ -+ for_each_entity(entity) { -+ __bfq_activate_entity(entity); -+ -+ sd = entity->sched_data; -+ if (!bfq_update_next_active(sd)) -+ /* -+ * No need to propagate the activation to the -+ * upper entities, as they will be updated when -+ * the active entity is rescheduled. -+ */ -+ break; -+ } -+} -+ -+/** -+ * __bfq_deactivate_entity - deactivate an entity from its service tree. -+ * @entity: the entity to deactivate. -+ * @requeue: if false, the entity will not be put into the idle tree. -+ * -+ * Deactivate an entity, independently from its previous state. If the -+ * entity was not on a service tree just return, otherwise if it is on -+ * any scheduler tree, extract it from that tree, and if necessary -+ * and if the caller did not specify @requeue, put it on the idle tree. -+ * -+ * Return %1 if the caller should update the entity hierarchy, i.e., -+ * if the entity was under service or if it was the next_active for -+ * its sched_data; return %0 otherwise. -+ */ -+static int __bfq_deactivate_entity(struct bfq_entity *entity, int requeue) -+{ -+ struct bfq_sched_data *sd = entity->sched_data; -+ struct bfq_service_tree *st = bfq_entity_service_tree(entity); -+ int was_active = entity == sd->active_entity; -+ int ret = 0; -+ -+ if (!entity->on_st) -+ return 0; -+ -+ BUG_ON(was_active && entity->tree != NULL); -+ -+ if (was_active) { -+ bfq_calc_finish(entity, entity->service); -+ sd->active_entity = NULL; -+ } else if (entity->tree == &st->active) -+ bfq_active_extract(st, entity); -+ else if (entity->tree == &st->idle) -+ bfq_idle_extract(st, entity); -+ else if (entity->tree != NULL) -+ BUG(); -+ -+ if (was_active || sd->next_active == entity) -+ ret = bfq_update_next_active(sd); -+ -+ if (!requeue || !bfq_gt(entity->finish, st->vtime)) -+ bfq_forget_entity(st, entity); -+ else -+ bfq_idle_insert(st, entity); -+ -+ BUG_ON(sd->active_entity == entity); -+ BUG_ON(sd->next_active == entity); -+ -+ return ret; -+} -+ -+/** -+ * bfq_deactivate_entity - deactivate an entity. -+ * @entity: the entity to deactivate. -+ * @requeue: true if the entity can be put on the idle tree -+ */ -+static void bfq_deactivate_entity(struct bfq_entity *entity, int requeue) -+{ -+ struct bfq_sched_data *sd; -+ struct bfq_entity *parent; -+ -+ for_each_entity_safe(entity, parent) { -+ sd = entity->sched_data; -+ -+ if (!__bfq_deactivate_entity(entity, requeue)) -+ /* -+ * The parent entity is still backlogged, and -+ * we don't need to update it as it is still -+ * under service. -+ */ -+ break; -+ -+ if (sd->next_active != NULL) -+ /* -+ * The parent entity is still backlogged and -+ * the budgets on the path towards the root -+ * need to be updated. -+ */ -+ goto update; -+ -+ /* -+ * If we reach there the parent is no more backlogged and -+ * we want to propagate the dequeue upwards. -+ */ -+ requeue = 1; -+ } -+ -+ return; -+ -+update: -+ entity = parent; -+ for_each_entity(entity) { -+ __bfq_activate_entity(entity); -+ -+ sd = entity->sched_data; -+ if (!bfq_update_next_active(sd)) -+ break; -+ } -+} -+ -+/** -+ * bfq_update_vtime - update vtime if necessary. -+ * @st: the service tree to act upon. -+ * -+ * If necessary update the service tree vtime to have at least one -+ * eligible entity, skipping to its start time. Assumes that the -+ * active tree of the device is not empty. -+ * -+ * NOTE: this hierarchical implementation updates vtimes quite often, -+ * we may end up with reactivated tasks getting timestamps after a -+ * vtime skip done because we needed a ->first_active entity on some -+ * intermediate node. -+ */ -+static void bfq_update_vtime(struct bfq_service_tree *st) -+{ -+ struct bfq_entity *entry; -+ struct rb_node *node = st->active.rb_node; -+ -+ entry = rb_entry(node, struct bfq_entity, rb_node); -+ if (bfq_gt(entry->min_start, st->vtime)) { -+ st->vtime = entry->min_start; -+ bfq_forget_idle(st); -+ } -+} -+ -+/** -+ * bfq_first_active - find the eligible entity with the smallest finish time -+ * @st: the service tree to select from. -+ * -+ * This function searches the first schedulable entity, starting from the -+ * root of the tree and going on the left every time on this side there is -+ * a subtree with at least one eligible (start >= vtime) entity. The path -+ * on the right is followed only if a) the left subtree contains no eligible -+ * entities and b) no eligible entity has been found yet. -+ */ -+static struct bfq_entity *bfq_first_active_entity(struct bfq_service_tree *st) -+{ -+ struct bfq_entity *entry, *first = NULL; -+ struct rb_node *node = st->active.rb_node; -+ -+ while (node != NULL) { -+ entry = rb_entry(node, struct bfq_entity, rb_node); -+left: -+ if (!bfq_gt(entry->start, st->vtime)) -+ first = entry; -+ -+ BUG_ON(bfq_gt(entry->min_start, st->vtime)); -+ -+ if (node->rb_left != NULL) { -+ entry = rb_entry(node->rb_left, -+ struct bfq_entity, rb_node); -+ if (!bfq_gt(entry->min_start, st->vtime)) { -+ node = node->rb_left; -+ goto left; -+ } -+ } -+ if (first != NULL) -+ break; -+ node = node->rb_right; -+ } -+ -+ BUG_ON(first == NULL && !RB_EMPTY_ROOT(&st->active)); -+ return first; -+} -+ -+/** -+ * __bfq_lookup_next_entity - return the first eligible entity in @st. -+ * @st: the service tree. -+ * -+ * Update the virtual time in @st and return the first eligible entity -+ * it contains. -+ */ -+static struct bfq_entity *__bfq_lookup_next_entity(struct bfq_service_tree *st, -+ bool force) -+{ -+ struct bfq_entity *entity, *new_next_active = NULL; -+ -+ if (RB_EMPTY_ROOT(&st->active)) -+ return NULL; -+ -+ bfq_update_vtime(st); -+ entity = bfq_first_active_entity(st); -+ BUG_ON(bfq_gt(entity->start, st->vtime)); -+ -+ /* -+ * If the chosen entity does not match with the sched_data's -+ * next_active and we are forcedly serving the IDLE priority -+ * class tree, bubble up budget update. -+ */ -+ if (unlikely(force && entity != entity->sched_data->next_active)) { -+ new_next_active = entity; -+ for_each_entity(new_next_active) -+ bfq_update_budget(new_next_active); -+ } -+ -+ return entity; -+} -+ -+/** -+ * bfq_lookup_next_entity - return the first eligible entity in @sd. -+ * @sd: the sched_data. -+ * @extract: if true the returned entity will be also extracted from @sd. -+ * -+ * NOTE: since we cache the next_active entity at each level of the -+ * hierarchy, the complexity of the lookup can be decreased with -+ * absolutely no effort just returning the cached next_active value; -+ * we prefer to do full lookups to test the consistency of * the data -+ * structures. -+ */ -+static struct bfq_entity *bfq_lookup_next_entity(struct bfq_sched_data *sd, -+ int extract, -+ struct bfq_data *bfqd) -+{ -+ struct bfq_service_tree *st = sd->service_tree; -+ struct bfq_entity *entity; -+ int i = 0; -+ -+ BUG_ON(sd->active_entity != NULL); -+ -+ if (bfqd != NULL && -+ jiffies - bfqd->bfq_class_idle_last_service > BFQ_CL_IDLE_TIMEOUT) { -+ entity = __bfq_lookup_next_entity(st + BFQ_IOPRIO_CLASSES - 1, -+ true); -+ if (entity != NULL) { -+ i = BFQ_IOPRIO_CLASSES - 1; -+ bfqd->bfq_class_idle_last_service = jiffies; -+ sd->next_active = entity; -+ } -+ } -+ for (; i < BFQ_IOPRIO_CLASSES; i++) { -+ entity = __bfq_lookup_next_entity(st + i, false); -+ if (entity != NULL) { -+ if (extract) { -+ bfq_check_next_active(sd, entity); -+ bfq_active_extract(st + i, entity); -+ sd->active_entity = entity; -+ sd->next_active = NULL; -+ } -+ break; -+ } -+ } -+ -+ return entity; -+} -+ -+/* -+ * Get next queue for service. -+ */ -+static struct bfq_queue *bfq_get_next_queue(struct bfq_data *bfqd) -+{ -+ struct bfq_entity *entity = NULL; -+ struct bfq_sched_data *sd; -+ struct bfq_queue *bfqq; -+ -+ BUG_ON(bfqd->in_service_queue != NULL); -+ -+ if (bfqd->busy_queues == 0) -+ return NULL; -+ -+ sd = &bfqd->root_group->sched_data; -+ for (; sd != NULL; sd = entity->my_sched_data) { -+ entity = bfq_lookup_next_entity(sd, 1, bfqd); -+ BUG_ON(entity == NULL); -+ entity->service = 0; -+ } -+ -+ bfqq = bfq_entity_to_bfqq(entity); -+ BUG_ON(bfqq == NULL); -+ -+ return bfqq; -+} -+ -+/* -+ * Forced extraction of the given queue. -+ */ -+static void bfq_get_next_queue_forced(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq) -+{ -+ struct bfq_entity *entity; -+ struct bfq_sched_data *sd; -+ -+ BUG_ON(bfqd->in_service_queue != NULL); -+ -+ entity = &bfqq->entity; -+ /* -+ * Bubble up extraction/update from the leaf to the root. -+ */ -+ for_each_entity(entity) { -+ sd = entity->sched_data; -+ bfq_update_budget(entity); -+ bfq_update_vtime(bfq_entity_service_tree(entity)); -+ bfq_active_extract(bfq_entity_service_tree(entity), entity); -+ sd->active_entity = entity; -+ sd->next_active = NULL; -+ entity->service = 0; -+ } -+ -+ return; -+} -+ -+static void __bfq_bfqd_reset_in_service(struct bfq_data *bfqd) -+{ -+ if (bfqd->in_service_bic != NULL) { -+ put_io_context(bfqd->in_service_bic->icq.ioc); -+ bfqd->in_service_bic = NULL; -+ } -+ -+ bfqd->in_service_queue = NULL; -+ del_timer(&bfqd->idle_slice_timer); -+} -+ -+static void bfq_deactivate_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq, -+ int requeue) -+{ -+ struct bfq_entity *entity = &bfqq->entity; -+ -+ if (bfqq == bfqd->in_service_queue) -+ __bfq_bfqd_reset_in_service(bfqd); -+ -+ bfq_deactivate_entity(entity, requeue); -+} -+ -+static void bfq_activate_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq) -+{ -+ struct bfq_entity *entity = &bfqq->entity; -+ -+ bfq_activate_entity(entity); -+} -+ -+/* -+ * Called when the bfqq no longer has requests pending, remove it from -+ * the service tree. -+ */ -+static void bfq_del_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq, -+ int requeue) -+{ -+ BUG_ON(!bfq_bfqq_busy(bfqq)); -+ BUG_ON(!RB_EMPTY_ROOT(&bfqq->sort_list)); -+ -+ bfq_log_bfqq(bfqd, bfqq, "del from busy"); -+ -+ bfq_clear_bfqq_busy(bfqq); -+ -+ BUG_ON(bfqd->busy_queues == 0); -+ bfqd->busy_queues--; -+ if (bfqq->raising_coeff > 1) -+ bfqd->raised_busy_queues--; -+ -+ bfq_deactivate_bfqq(bfqd, bfqq, requeue); -+} -+ -+/* -+ * Called when an inactive queue receives a new request. -+ */ -+static void bfq_add_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq) -+{ -+ BUG_ON(bfq_bfqq_busy(bfqq)); -+ BUG_ON(bfqq == bfqd->in_service_queue); -+ -+ bfq_log_bfqq(bfqd, bfqq, "add to busy"); -+ -+ bfq_activate_bfqq(bfqd, bfqq); -+ -+ bfq_mark_bfqq_busy(bfqq); -+ bfqd->busy_queues++; -+ if (bfqq->raising_coeff > 1) -+ bfqd->raised_busy_queues++; -+} -diff --git a/block/bfq.h b/block/bfq.h -new file mode 100644 -index 0000000..78da7d2 ---- /dev/null -+++ b/block/bfq.h -@@ -0,0 +1,612 @@ -+/* -+ * BFQ-v7 for 3.10.0: data structures and common functions prototypes. -+ * -+ * Based on ideas and code from CFQ: -+ * Copyright (C) 2003 Jens Axboe -+ * -+ * Copyright (C) 2008 Fabio Checconi -+ * Paolo Valente -+ * -+ * Copyright (C) 2010 Paolo Valente -+ */ -+ -+#ifndef _BFQ_H -+#define _BFQ_H -+ -+#include -+#include -+#include -+#include -+ -+#define BFQ_IOPRIO_CLASSES 3 -+#define BFQ_CL_IDLE_TIMEOUT (HZ/5) -+ -+#define BFQ_MIN_WEIGHT 1 -+#define BFQ_MAX_WEIGHT 1000 -+ -+#define BFQ_DEFAULT_GRP_WEIGHT 10 -+#define BFQ_DEFAULT_GRP_IOPRIO 0 -+#define BFQ_DEFAULT_GRP_CLASS IOPRIO_CLASS_BE -+ -+struct bfq_entity; -+ -+/** -+ * struct bfq_service_tree - per ioprio_class service tree. -+ * @active: tree for active entities (i.e., those backlogged). -+ * @idle: tree for idle entities (i.e., those not backlogged, with V <= F_i). -+ * @first_idle: idle entity with minimum F_i. -+ * @last_idle: idle entity with maximum F_i. -+ * @vtime: scheduler virtual time. -+ * @wsum: scheduler weight sum; active and idle entities contribute to it. -+ * -+ * Each service tree represents a B-WF2Q+ scheduler on its own. Each -+ * ioprio_class has its own independent scheduler, and so its own -+ * bfq_service_tree. All the fields are protected by the queue lock -+ * of the containing bfqd. -+ */ -+struct bfq_service_tree { -+ struct rb_root active; -+ struct rb_root idle; -+ -+ struct bfq_entity *first_idle; -+ struct bfq_entity *last_idle; -+ -+ u64 vtime; -+ unsigned long wsum; -+}; -+ -+/** -+ * struct bfq_sched_data - multi-class scheduler. -+ * @active_entity: entity under service. -+ * @next_active: head-of-the-line entity in the scheduler. -+ * @service_tree: array of service trees, one per ioprio_class. -+ * -+ * bfq_sched_data is the basic scheduler queue. It supports three -+ * ioprio_classes, and can be used either as a toplevel queue or as -+ * an intermediate queue on a hierarchical setup. -+ * @next_active points to the active entity of the sched_data service -+ * trees that will be scheduled next. -+ * -+ * The supported ioprio_classes are the same as in CFQ, in descending -+ * priority order, IOPRIO_CLASS_RT, IOPRIO_CLASS_BE, IOPRIO_CLASS_IDLE. -+ * Requests from higher priority queues are served before all the -+ * requests from lower priority queues; among requests of the same -+ * queue requests are served according to B-WF2Q+. -+ * All the fields are protected by the queue lock of the containing bfqd. -+ */ -+struct bfq_sched_data { -+ struct bfq_entity *active_entity; -+ struct bfq_entity *next_active; -+ struct bfq_service_tree service_tree[BFQ_IOPRIO_CLASSES]; -+}; -+ -+/** -+ * struct bfq_entity - schedulable entity. -+ * @rb_node: service_tree member. -+ * @on_st: flag, true if the entity is on a tree (either the active or -+ * the idle one of its service_tree). -+ * @finish: B-WF2Q+ finish timestamp (aka F_i). -+ * @start: B-WF2Q+ start timestamp (aka S_i). -+ * @tree: tree the entity is enqueued into; %NULL if not on a tree. -+ * @min_start: minimum start time of the (active) subtree rooted at -+ * this entity; used for O(log N) lookups into active trees. -+ * @service: service received during the last round of service. -+ * @budget: budget used to calculate F_i; F_i = S_i + @budget / @weight. -+ * @weight: weight of the queue -+ * @parent: parent entity, for hierarchical scheduling. -+ * @my_sched_data: for non-leaf nodes in the cgroup hierarchy, the -+ * associated scheduler queue, %NULL on leaf nodes. -+ * @sched_data: the scheduler queue this entity belongs to. -+ * @ioprio: the ioprio in use. -+ * @new_weight: when a weight change is requested, the new weight value. -+ * @orig_weight: original weight, used to implement weight boosting -+ * @new_ioprio: when an ioprio change is requested, the new ioprio value. -+ * @ioprio_class: the ioprio_class in use. -+ * @new_ioprio_class: when an ioprio_class change is requested, the new -+ * ioprio_class value. -+ * @ioprio_changed: flag, true when the user requested a weight, ioprio or -+ * ioprio_class change. -+ * -+ * A bfq_entity is used to represent either a bfq_queue (leaf node in the -+ * cgroup hierarchy) or a bfq_group into the upper level scheduler. Each -+ * entity belongs to the sched_data of the parent group in the cgroup -+ * hierarchy. Non-leaf entities have also their own sched_data, stored -+ * in @my_sched_data. -+ * -+ * Each entity stores independently its priority values; this would -+ * allow different weights on different devices, but this -+ * functionality is not exported to userspace by now. Priorities and -+ * weights are updated lazily, first storing the new values into the -+ * new_* fields, then setting the @ioprio_changed flag. As soon as -+ * there is a transition in the entity state that allows the priority -+ * update to take place the effective and the requested priority -+ * values are synchronized. -+ * -+ * Unless cgroups are used, the weight value is calculated from the -+ * ioprio to export the same interface as CFQ. When dealing with -+ * ``well-behaved'' queues (i.e., queues that do not spend too much -+ * time to consume their budget and have true sequential behavior, and -+ * when there are no external factors breaking anticipation) the -+ * relative weights at each level of the cgroups hierarchy should be -+ * guaranteed. All the fields are protected by the queue lock of the -+ * containing bfqd. -+ */ -+struct bfq_entity { -+ struct rb_node rb_node; -+ -+ int on_st; -+ -+ u64 finish; -+ u64 start; -+ -+ struct rb_root *tree; -+ -+ u64 min_start; -+ -+ unsigned long service, budget; -+ unsigned short weight, new_weight; -+ unsigned short orig_weight; -+ -+ struct bfq_entity *parent; -+ -+ struct bfq_sched_data *my_sched_data; -+ struct bfq_sched_data *sched_data; -+ -+ unsigned short ioprio, new_ioprio; -+ unsigned short ioprio_class, new_ioprio_class; -+ -+ int ioprio_changed; -+}; -+ -+struct bfq_group; -+ -+/** -+ * struct bfq_queue - leaf schedulable entity. -+ * @ref: reference counter. -+ * @bfqd: parent bfq_data. -+ * @new_bfqq: shared bfq_queue if queue is cooperating with -+ * one or more other queues. -+ * @pos_node: request-position tree member (see bfq_data's @rq_pos_tree). -+ * @pos_root: request-position tree root (see bfq_data's @rq_pos_tree). -+ * @sort_list: sorted list of pending requests. -+ * @next_rq: if fifo isn't expired, next request to serve. -+ * @queued: nr of requests queued in @sort_list. -+ * @allocated: currently allocated requests. -+ * @meta_pending: pending metadata requests. -+ * @fifo: fifo list of requests in sort_list. -+ * @entity: entity representing this queue in the scheduler. -+ * @max_budget: maximum budget allowed from the feedback mechanism. -+ * @budget_timeout: budget expiration (in jiffies). -+ * @dispatched: number of requests on the dispatch list or inside driver. -+ * @org_ioprio: saved ioprio during boosted periods. -+ * @flags: status flags. -+ * @bfqq_list: node for active/idle bfqq list inside our bfqd. -+ * @seek_samples: number of seeks sampled -+ * @seek_total: sum of the distances of the seeks sampled -+ * @seek_mean: mean seek distance -+ * @last_request_pos: position of the last request enqueued -+ * @pid: pid of the process owning the queue, used for logging purposes. -+ * @last_rais_start_time: last (idle -> weight-raised) transition attempt -+ * @raising_cur_max_time: current max raising time for this queue -+ * @last_idle_bklogged: time of the last transition of the @bfq_queue from -+ * idle to backlogged -+ * @service_from_backlogged: cumulative service received from the @bfq_queue -+ * since the last transition from idle to backlogged -+ * -+ * A bfq_queue is a leaf request queue; it can be associated to an io_context -+ * or more (if it is an async one). @cgroup holds a reference to the -+ * cgroup, to be sure that it does not disappear while a bfqq still -+ * references it (mostly to avoid races between request issuing and task -+ * migration followed by cgroup distruction). -+ * All the fields are protected by the queue lock of the containing bfqd. -+ */ -+struct bfq_queue { -+ atomic_t ref; -+ struct bfq_data *bfqd; -+ -+ /* fields for cooperating queues handling */ -+ struct bfq_queue *new_bfqq; -+ struct rb_node pos_node; -+ struct rb_root *pos_root; -+ -+ struct rb_root sort_list; -+ struct request *next_rq; -+ int queued[2]; -+ int allocated[2]; -+ int meta_pending; -+ struct list_head fifo; -+ -+ struct bfq_entity entity; -+ -+ unsigned long max_budget; -+ unsigned long budget_timeout; -+ -+ int dispatched; -+ -+ unsigned short org_ioprio; -+ -+ unsigned int flags; -+ -+ struct list_head bfqq_list; -+ -+ unsigned int seek_samples; -+ u64 seek_total; -+ sector_t seek_mean; -+ sector_t last_request_pos; -+ -+ pid_t pid; -+ -+ /* weight-raising fields */ -+ unsigned int raising_cur_max_time; -+ unsigned long soft_rt_next_start; -+ u64 last_rais_start_finish; -+ unsigned int raising_coeff; -+ u64 last_idle_bklogged; -+ unsigned long service_from_backlogged; -+}; -+ -+/** -+ * struct bfq_ttime - per process thinktime stats. -+ * @ttime_total: total process thinktime -+ * @ttime_samples: number of thinktime samples -+ * @ttime_mean: average process thinktime -+ */ -+struct bfq_ttime { -+ unsigned long last_end_request; -+ -+ unsigned long ttime_total; -+ unsigned long ttime_samples; -+ unsigned long ttime_mean; -+}; -+ -+/** -+ * struct bfq_io_cq - per (request_queue, io_context) structure. -+ * @icq: associated io_cq structure -+ * @bfqq: array of two process queues, the sync and the async -+ * @ttime: associated @bfq_ttime struct -+ */ -+struct bfq_io_cq { -+ struct io_cq icq; /* must be the first member */ -+ struct bfq_queue *bfqq[2]; -+ struct bfq_ttime ttime; -+ int ioprio; -+}; -+ -+/** -+ * struct bfq_data - per device data structure. -+ * @queue: request queue for the managed device. -+ * @root_group: root bfq_group for the device. -+ * @rq_pos_tree: rbtree sorted by next_request position, -+ * used when determining if two or more queues -+ * have interleaving requests (see bfq_close_cooperator). -+ * @busy_queues: number of bfq_queues containing requests (including the -+ * queue under service, even if it is idling). -+ * @raised_busy_queues: number of weight-raised busy bfq_queues. -+ * @queued: number of queued requests. -+ * @rq_in_driver: number of requests dispatched and waiting for completion. -+ * @sync_flight: number of sync requests in the driver. -+ * @max_rq_in_driver: max number of reqs in driver in the last @hw_tag_samples -+ * completed requests . -+ * @hw_tag_samples: nr of samples used to calculate hw_tag. -+ * @hw_tag: flag set to one if the driver is showing a queueing behavior. -+ * @budgets_assigned: number of budgets assigned. -+ * @idle_slice_timer: timer set when idling for the next sequential request -+ * from the queue under service. -+ * @unplug_work: delayed work to restart dispatching on the request queue. -+ * @in_service_queue: bfq_queue under service. -+ * @in_service_bic: bfq_io_cq (bic) associated with the @in_service_queue. -+ * @last_position: on-disk position of the last served request. -+ * @last_budget_start: beginning of the last budget. -+ * @last_idling_start: beginning of the last idle slice. -+ * @peak_rate: peak transfer rate observed for a budget. -+ * @peak_rate_samples: number of samples used to calculate @peak_rate. -+ * @bfq_max_budget: maximum budget allotted to a bfq_queue before rescheduling. -+ * @group_list: list of all the bfq_groups active on the device. -+ * @active_list: list of all the bfq_queues active on the device. -+ * @idle_list: list of all the bfq_queues idle on the device. -+ * @bfq_quantum: max number of requests dispatched per dispatch round. -+ * @bfq_fifo_expire: timeout for async/sync requests; when it expires -+ * requests are served in fifo order. -+ * @bfq_back_penalty: weight of backward seeks wrt forward ones. -+ * @bfq_back_max: maximum allowed backward seek. -+ * @bfq_slice_idle: maximum idling time. -+ * @bfq_user_max_budget: user-configured max budget value (0 for auto-tuning). -+ * @bfq_max_budget_async_rq: maximum budget (in nr of requests) allotted to -+ * async queues. -+ * @bfq_timeout: timeout for bfq_queues to consume their budget; used to -+ * to prevent seeky queues to impose long latencies to well -+ * behaved ones (this also implies that seeky queues cannot -+ * receive guarantees in the service domain; after a timeout -+ * they are charged for the whole allocated budget, to try -+ * to preserve a behavior reasonably fair among them, but -+ * without service-domain guarantees). -+ * @bfq_raising_coeff: Maximum factor by which the weight of a boosted -+ * queue is multiplied -+ * @bfq_raising_max_time: maximum duration of a weight-raising period (jiffies) -+ * @bfq_raising_rt_max_time: maximum duration for soft real-time processes -+ * @bfq_raising_min_idle_time: minimum idle period after which weight-raising -+ * may be reactivated for a queue (in jiffies) -+ * @bfq_raising_min_inter_arr_async: minimum period between request arrivals -+ * after which weight-raising may be -+ * reactivated for an already busy queue -+ * (in jiffies) -+ * @bfq_raising_max_softrt_rate: max service-rate for a soft real-time queue, -+ * sectors per seconds -+ * @RT_prod: cached value of the product R*T used for computing the maximum -+ * duration of the weight raising automatically -+ * @oom_bfqq: fallback dummy bfqq for extreme OOM conditions -+ * -+ * All the fields are protected by the @queue lock. -+ */ -+struct bfq_data { -+ struct request_queue *queue; -+ -+ struct bfq_group *root_group; -+ -+ struct rb_root rq_pos_tree; -+ -+ int busy_queues; -+ int raised_busy_queues; -+ int queued; -+ int rq_in_driver; -+ int sync_flight; -+ -+ int max_rq_in_driver; -+ int hw_tag_samples; -+ int hw_tag; -+ -+ int budgets_assigned; -+ -+ struct timer_list idle_slice_timer; -+ struct work_struct unplug_work; -+ -+ struct bfq_queue *in_service_queue; -+ struct bfq_io_cq *in_service_bic; -+ -+ sector_t last_position; -+ -+ ktime_t last_budget_start; -+ ktime_t last_idling_start; -+ int peak_rate_samples; -+ u64 peak_rate; -+ unsigned long bfq_max_budget; -+ -+ struct hlist_head group_list; -+ struct list_head active_list; -+ struct list_head idle_list; -+ -+ unsigned int bfq_quantum; -+ unsigned int bfq_fifo_expire[2]; -+ unsigned int bfq_back_penalty; -+ unsigned int bfq_back_max; -+ unsigned int bfq_slice_idle; -+ u64 bfq_class_idle_last_service; -+ -+ unsigned int bfq_user_max_budget; -+ unsigned int bfq_max_budget_async_rq; -+ unsigned int bfq_timeout[2]; -+ -+ bool low_latency; -+ -+ /* parameters of the low_latency heuristics */ -+ unsigned int bfq_raising_coeff; -+ unsigned int bfq_raising_max_time; -+ unsigned int bfq_raising_rt_max_time; -+ unsigned int bfq_raising_min_idle_time; -+ unsigned long bfq_raising_min_inter_arr_async; -+ unsigned int bfq_raising_max_softrt_rate; -+ u64 RT_prod; -+ -+ struct bfq_queue oom_bfqq; -+}; -+ -+enum bfqq_state_flags { -+ BFQ_BFQQ_FLAG_busy = 0, /* has requests or is under service */ -+ BFQ_BFQQ_FLAG_wait_request, /* waiting for a request */ -+ BFQ_BFQQ_FLAG_must_alloc, /* must be allowed rq alloc */ -+ BFQ_BFQQ_FLAG_fifo_expire, /* FIFO checked in this slice */ -+ BFQ_BFQQ_FLAG_idle_window, /* slice idling enabled */ -+ BFQ_BFQQ_FLAG_prio_changed, /* task priority has changed */ -+ BFQ_BFQQ_FLAG_sync, /* synchronous queue */ -+ BFQ_BFQQ_FLAG_budget_new, /* no completion with this budget */ -+ BFQ_BFQQ_FLAG_coop, /* bfqq is shared */ -+ BFQ_BFQQ_FLAG_split_coop, /* shared bfqq will be splitted */ -+ BFQ_BFQQ_FLAG_softrt_update, /* needs softrt-next-start update */ -+}; -+ -+#define BFQ_BFQQ_FNS(name) \ -+static inline void bfq_mark_bfqq_##name(struct bfq_queue *bfqq) \ -+{ \ -+ (bfqq)->flags |= (1 << BFQ_BFQQ_FLAG_##name); \ -+} \ -+static inline void bfq_clear_bfqq_##name(struct bfq_queue *bfqq) \ -+{ \ -+ (bfqq)->flags &= ~(1 << BFQ_BFQQ_FLAG_##name); \ -+} \ -+static inline int bfq_bfqq_##name(const struct bfq_queue *bfqq) \ -+{ \ -+ return ((bfqq)->flags & (1 << BFQ_BFQQ_FLAG_##name)) != 0; \ -+} -+ -+BFQ_BFQQ_FNS(busy); -+BFQ_BFQQ_FNS(wait_request); -+BFQ_BFQQ_FNS(must_alloc); -+BFQ_BFQQ_FNS(fifo_expire); -+BFQ_BFQQ_FNS(idle_window); -+BFQ_BFQQ_FNS(prio_changed); -+BFQ_BFQQ_FNS(sync); -+BFQ_BFQQ_FNS(budget_new); -+BFQ_BFQQ_FNS(coop); -+BFQ_BFQQ_FNS(split_coop); -+BFQ_BFQQ_FNS(softrt_update); -+#undef BFQ_BFQQ_FNS -+ -+/* Logging facilities. */ -+#define bfq_log_bfqq(bfqd, bfqq, fmt, args...) \ -+ blk_add_trace_msg((bfqd)->queue, "bfq%d " fmt, (bfqq)->pid, ##args) -+ -+#define bfq_log(bfqd, fmt, args...) \ -+ blk_add_trace_msg((bfqd)->queue, "bfq " fmt, ##args) -+ -+/* Expiration reasons. */ -+enum bfqq_expiration { -+ BFQ_BFQQ_TOO_IDLE = 0, /* queue has been idling for too long */ -+ BFQ_BFQQ_BUDGET_TIMEOUT, /* budget took too long to be used */ -+ BFQ_BFQQ_BUDGET_EXHAUSTED, /* budget consumed */ -+ BFQ_BFQQ_NO_MORE_REQUESTS, /* the queue has no more requests */ -+}; -+ -+#ifdef CONFIG_CGROUP_BFQIO -+/** -+ * struct bfq_group - per (device, cgroup) data structure. -+ * @entity: schedulable entity to insert into the parent group sched_data. -+ * @sched_data: own sched_data, to contain child entities (they may be -+ * both bfq_queues and bfq_groups). -+ * @group_node: node to be inserted into the bfqio_cgroup->group_data -+ * list of the containing cgroup's bfqio_cgroup. -+ * @bfqd_node: node to be inserted into the @bfqd->group_list list -+ * of the groups active on the same device; used for cleanup. -+ * @bfqd: the bfq_data for the device this group acts upon. -+ * @async_bfqq: array of async queues for all the tasks belonging to -+ * the group, one queue per ioprio value per ioprio_class, -+ * except for the idle class that has only one queue. -+ * @async_idle_bfqq: async queue for the idle class (ioprio is ignored). -+ * @my_entity: pointer to @entity, %NULL for the toplevel group; used -+ * to avoid too many special cases during group creation/migration. -+ * -+ * Each (device, cgroup) pair has its own bfq_group, i.e., for each cgroup -+ * there is a set of bfq_groups, each one collecting the lower-level -+ * entities belonging to the group that are acting on the same device. -+ * -+ * Locking works as follows: -+ * o @group_node is protected by the bfqio_cgroup lock, and is accessed -+ * via RCU from its readers. -+ * o @bfqd is protected by the queue lock, RCU is used to access it -+ * from the readers. -+ * o All the other fields are protected by the @bfqd queue lock. -+ */ -+struct bfq_group { -+ struct bfq_entity entity; -+ struct bfq_sched_data sched_data; -+ -+ struct hlist_node group_node; -+ struct hlist_node bfqd_node; -+ -+ void *bfqd; -+ -+ struct bfq_queue *async_bfqq[2][IOPRIO_BE_NR]; -+ struct bfq_queue *async_idle_bfqq; -+ -+ struct bfq_entity *my_entity; -+}; -+ -+/** -+ * struct bfqio_cgroup - bfq cgroup data structure. -+ * @css: subsystem state for bfq in the containing cgroup. -+ * @weight: cgroup weight. -+ * @ioprio: cgroup ioprio. -+ * @ioprio_class: cgroup ioprio_class. -+ * @lock: spinlock that protects @ioprio, @ioprio_class and @group_data. -+ * @group_data: list containing the bfq_group belonging to this cgroup. -+ * -+ * @group_data is accessed using RCU, with @lock protecting the updates, -+ * @ioprio and @ioprio_class are protected by @lock. -+ */ -+struct bfqio_cgroup { -+ struct cgroup_subsys_state css; -+ -+ unsigned short weight, ioprio, ioprio_class; -+ -+ spinlock_t lock; -+ struct hlist_head group_data; -+}; -+#else -+struct bfq_group { -+ struct bfq_sched_data sched_data; -+ -+ struct bfq_queue *async_bfqq[2][IOPRIO_BE_NR]; -+ struct bfq_queue *async_idle_bfqq; -+}; -+#endif -+ -+static inline struct bfq_service_tree * -+bfq_entity_service_tree(struct bfq_entity *entity) -+{ -+ struct bfq_sched_data *sched_data = entity->sched_data; -+ unsigned int idx = entity->ioprio_class - 1; -+ -+ BUG_ON(idx >= BFQ_IOPRIO_CLASSES); -+ BUG_ON(sched_data == NULL); -+ -+ return sched_data->service_tree + idx; -+} -+ -+static inline struct bfq_queue *bic_to_bfqq(struct bfq_io_cq *bic, -+ int is_sync) -+{ -+ return bic->bfqq[!!is_sync]; -+} -+ -+static inline void bic_set_bfqq(struct bfq_io_cq *bic, -+ struct bfq_queue *bfqq, int is_sync) -+{ -+ bic->bfqq[!!is_sync] = bfqq; -+} -+ -+static inline struct bfq_data *bic_to_bfqd(struct bfq_io_cq *bic) -+{ -+ return bic->icq.q->elevator->elevator_data; -+} -+ -+/** -+ * bfq_get_bfqd_locked - get a lock to a bfqd using a RCU protected pointer. -+ * @ptr: a pointer to a bfqd. -+ * @flags: storage for the flags to be saved. -+ * -+ * This function allows bfqg->bfqd to be protected by the -+ * queue lock of the bfqd they reference; the pointer is dereferenced -+ * under RCU, so the storage for bfqd is assured to be safe as long -+ * as the RCU read side critical section does not end. After the -+ * bfqd->queue->queue_lock is taken the pointer is rechecked, to be -+ * sure that no other writer accessed it. If we raced with a writer, -+ * the function returns NULL, with the queue unlocked, otherwise it -+ * returns the dereferenced pointer, with the queue locked. -+ */ -+static inline struct bfq_data *bfq_get_bfqd_locked(void **ptr, -+ unsigned long *flags) -+{ -+ struct bfq_data *bfqd; -+ -+ rcu_read_lock(); -+ bfqd = rcu_dereference(*(struct bfq_data **)ptr); -+ -+ if (bfqd != NULL) { -+ spin_lock_irqsave(bfqd->queue->queue_lock, *flags); -+ if (*ptr == bfqd) -+ goto out; -+ spin_unlock_irqrestore(bfqd->queue->queue_lock, *flags); -+ } -+ -+ bfqd = NULL; -+out: -+ rcu_read_unlock(); -+ return bfqd; -+} -+ -+static inline void bfq_put_bfqd_unlock(struct bfq_data *bfqd, -+ unsigned long *flags) -+{ -+ spin_unlock_irqrestore(bfqd->queue->queue_lock, *flags); -+} -+ -+static void bfq_changed_ioprio(struct bfq_io_cq *bic); -+static void bfq_put_queue(struct bfq_queue *bfqq); -+static void bfq_dispatch_insert(struct request_queue *q, struct request *rq); -+static struct bfq_queue *bfq_get_queue(struct bfq_data *bfqd, -+ struct bfq_group *bfqg, int is_sync, -+ struct bfq_io_cq *bic, gfp_t gfp_mask); -+static void bfq_end_raising_async_queues(struct bfq_data *bfqd, -+ struct bfq_group *bfqg); -+static void bfq_put_async_queues(struct bfq_data *bfqd, struct bfq_group *bfqg); -+static void bfq_exit_bfqq(struct bfq_data *bfqd, struct bfq_queue *bfqq); -+#endif --- -1.8.5.2 - diff --git a/sys-kernel/kogaion-sources/files/desktop/0003-block-bfq-add-Early-Queue-Merge-EQM-to-BFQ-v7-for-3.10.0.patch b/sys-kernel/kogaion-sources/files/desktop/0003-block-bfq-add-Early-Queue-Merge-EQM-to-BFQ-v7-for-3.10.0.patch deleted file mode 100644 index ea585f02..00000000 --- a/sys-kernel/kogaion-sources/files/desktop/0003-block-bfq-add-Early-Queue-Merge-EQM-to-BFQ-v7-for-3.10.0.patch +++ /dev/null @@ -1,1034 +0,0 @@ -From efc499347ea3827417cf00718616bf61a090afec Mon Sep 17 00:00:00 2001 -From: Mauro Andreolini -Date: Thu, 23 Jan 2014 16:54:44 +0100 -Subject: [PATCH 3/3] block, bfq: add Early Queue Merge (EQM) to BFQ-v7 for - 3.10.0 - -A set of processes may happen to perform interleaved reads, i.e., requests -whose union would give rise to a sequential read pattern. There are two -typical cases: in the first case, processes read fixed-size chunks of -data at a fixed distance from each other, while in the second case processes -may read variable-size chunks at variable distances. The latter case occurs -for example with KVM, which splits the I/O generated by the guest into -multiple chunks, and lets these chunks be served by a pool of cooperating -processes, iteratively assigning the next chunk of I/O to the first -available process. CFQ uses actual queue merging for the first type of -rocesses, whereas it uses preemption to get a sequential read pattern out -of the read requests performed by the second type of processes. In the end -it uses two different mechanisms to achieve the same goal: boosting the -throughput with interleaved I/O. - -This patch introduces Early Queue Merge (EQM), a unified mechanism to get a -sequential read pattern with both types of processes. The main idea is -checking newly arrived requests against the next request of the active queue -both in case of actual request insert and in case of request merge. By doing -so, both the types of processes can be handled by just merging their queues. -EQM is then simpler and more compact than the pair of mechanisms used in -CFQ. - -Finally, EQM also preserves the typical low-latency properties of BFQ, by -properly restoring the weight-raising state of a queue when it gets back to -a non-merged state. - -Signed-off-by: Mauro Andreolini -Signed-off-by: Arianna Avanzini -Reviewed-by: Paolo Valente ---- - block/bfq-iosched.c | 657 ++++++++++++++++++++++++++++++++++++---------------- - block/bfq-sched.c | 28 --- - block/bfq.h | 16 ++ - 3 files changed, 474 insertions(+), 227 deletions(-) - -diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c -index 96abb81..99083be6 100644 ---- a/block/bfq-iosched.c -+++ b/block/bfq-iosched.c -@@ -445,6 +445,46 @@ static inline unsigned int bfq_wrais_duration(struct bfq_data *bfqd) - return dur; - } - -+static inline void -+bfq_bfqq_resume_state(struct bfq_queue *bfqq, struct bfq_io_cq *bic) -+{ -+ if (bic->saved_idle_window) -+ bfq_mark_bfqq_idle_window(bfqq); -+ else -+ bfq_clear_bfqq_idle_window(bfqq); -+ if (bic->raising_time_left && bfqq->bfqd->low_latency) { -+ /* -+ * Start a weight raising period with the duration given by -+ * the raising_time_left snapshot. -+ */ -+ if (bfq_bfqq_busy(bfqq)) -+ bfqq->bfqd->raised_busy_queues++; -+ bfqq->raising_coeff = bfqq->bfqd->bfq_raising_coeff; -+ bfqq->raising_cur_max_time = bic->raising_time_left; -+ bfqq->last_rais_start_finish = jiffies; -+ bfqq->entity.ioprio_changed = 1; -+ } -+ /* -+ * Clear raising_time_left to prevent bfq_bfqq_save_state() from -+ * getting confused about the queue's need of a weight-raising -+ * period. -+ */ -+ bic->raising_time_left = 0; -+} -+ -+/* -+ * Must be called with the queue_lock held. -+ */ -+static int bfqq_process_refs(struct bfq_queue *bfqq) -+{ -+ int process_refs, io_refs; -+ -+ io_refs = bfqq->allocated[READ] + bfqq->allocated[WRITE]; -+ process_refs = atomic_read(&bfqq->ref) - io_refs - bfqq->entity.on_st; -+ BUG_ON(process_refs < 0); -+ return process_refs; -+} -+ - static void bfq_add_rq_rb(struct request *rq) - { - struct bfq_queue *bfqq = RQ_BFQQ(rq); -@@ -486,12 +526,20 @@ static void bfq_add_rq_rb(struct request *rq) - if (!bfqd->low_latency) - goto add_bfqq_busy; - -+ if (bfq_bfqq_just_split(bfqq)) -+ goto set_ioprio_changed; -+ - /* -- * If the queue is not being boosted and has been idle -- * for enough time, start a weight-raising period -+ * If the queue: -+ * - is not being boosted, -+ * - has been idle for enough time, -+ * - is not a sync queue or is linked to a bfq_io_cq (it is -+ * shared "for its nature" or it is not shared and its -+ * requests have not been redirected to a shared queue) -+ * start a weight-raising period. - */ -- if (old_raising_coeff == 1 && -- (idle_for_long_time || soft_rt)) { -+ if (old_raising_coeff == 1 && (idle_for_long_time || soft_rt) && -+ (!bfq_bfqq_sync(bfqq) || bfqq->bic != NULL)) { - bfqq->raising_coeff = bfqd->bfq_raising_coeff; - if (idle_for_long_time) - bfqq->raising_cur_max_time = -@@ -572,6 +620,7 @@ static void bfq_add_rq_rb(struct request *rq) - bfqd->bfq_raising_rt_max_time; - } - } -+set_ioprio_changed: - if (old_raising_coeff != bfqq->raising_coeff) - entity->ioprio_changed = 1; - add_bfqq_busy: -@@ -754,90 +803,35 @@ static void bfq_end_raising(struct bfq_data *bfqd) - spin_unlock_irq(bfqd->queue->queue_lock); - } - --static int bfq_allow_merge(struct request_queue *q, struct request *rq, -- struct bio *bio) --{ -- struct bfq_data *bfqd = q->elevator->elevator_data; -- struct bfq_io_cq *bic; -- struct bfq_queue *bfqq; -- -- /* -- * Disallow merge of a sync bio into an async request. -- */ -- if (bfq_bio_sync(bio) && !rq_is_sync(rq)) -- return 0; -- -- /* -- * Lookup the bfqq that this bio will be queued with. Allow -- * merge only if rq is queued there. -- * Queue lock is held here. -- */ -- bic = bfq_bic_lookup(bfqd, current->io_context); -- if (bic == NULL) -- return 0; -- -- bfqq = bic_to_bfqq(bic, bfq_bio_sync(bio)); -- return bfqq == RQ_BFQQ(rq); --} -- --static void __bfq_set_in_service_queue(struct bfq_data *bfqd, -- struct bfq_queue *bfqq) --{ -- if (bfqq != NULL) { -- bfq_mark_bfqq_must_alloc(bfqq); -- bfq_mark_bfqq_budget_new(bfqq); -- bfq_clear_bfqq_fifo_expire(bfqq); -- -- bfqd->budgets_assigned = (bfqd->budgets_assigned*7 + 256) / 8; -- -- bfq_log_bfqq(bfqd, bfqq, -- "set_in_service_queue, cur-budget = %lu", -- bfqq->entity.budget); -- } -- -- bfqd->in_service_queue = bfqq; --} -- --/* -- * Get and set a new queue for service. -- */ --static struct bfq_queue *bfq_set_in_service_queue(struct bfq_data *bfqd, -- struct bfq_queue *bfqq) -+static inline sector_t bfq_io_struct_pos(void *io_struct, bool request) - { -- if (!bfqq) -- bfqq = bfq_get_next_queue(bfqd); -+ if (request) -+ return blk_rq_pos(io_struct); - else -- bfq_get_next_queue_forced(bfqd, bfqq); -- -- __bfq_set_in_service_queue(bfqd, bfqq); -- return bfqq; -+ return ((struct bio *)io_struct)->bi_sector; - } - --static inline sector_t bfq_dist_from_last(struct bfq_data *bfqd, -- struct request *rq) -+static inline sector_t bfq_dist_from(sector_t pos1, -+ sector_t pos2) - { -- if (blk_rq_pos(rq) >= bfqd->last_position) -- return blk_rq_pos(rq) - bfqd->last_position; -+ if (pos1 >= pos2) -+ return pos1 - pos2; - else -- return bfqd->last_position - blk_rq_pos(rq); -+ return pos2 - pos1; - } - --/* -- * Return true if bfqq has no request pending and rq is close enough to -- * bfqd->last_position, or if rq is closer to bfqd->last_position than -- * bfqq->next_rq -- */ --static inline int bfq_rq_close(struct bfq_data *bfqd, struct request *rq) -+static inline int bfq_rq_close_to_sector(void *io_struct, bool request, -+ sector_t sector) - { -- return bfq_dist_from_last(bfqd, rq) <= BFQQ_SEEK_THR; -+ return bfq_dist_from(bfq_io_struct_pos(io_struct, request), sector) <= -+ BFQQ_SEEK_THR; - } - --static struct bfq_queue *bfqq_close(struct bfq_data *bfqd) -+static struct bfq_queue *bfqq_close(struct bfq_data *bfqd, sector_t sector) - { - struct rb_root *root = &bfqd->rq_pos_tree; - struct rb_node *parent, *node; - struct bfq_queue *__bfqq; -- sector_t sector = bfqd->last_position; - - if (RB_EMPTY_ROOT(root)) - return NULL; -@@ -856,7 +850,7 @@ static struct bfq_queue *bfqq_close(struct bfq_data *bfqd) - * position). - */ - __bfqq = rb_entry(parent, struct bfq_queue, pos_node); -- if (bfq_rq_close(bfqd, __bfqq->next_rq)) -+ if (bfq_rq_close_to_sector(__bfqq->next_rq, true, sector)) - return __bfqq; - - if (blk_rq_pos(__bfqq->next_rq) < sector) -@@ -867,7 +861,7 @@ static struct bfq_queue *bfqq_close(struct bfq_data *bfqd) - return NULL; - - __bfqq = rb_entry(node, struct bfq_queue, pos_node); -- if (bfq_rq_close(bfqd, __bfqq->next_rq)) -+ if (bfq_rq_close_to_sector(__bfqq->next_rq, true, sector)) - return __bfqq; - - return NULL; -@@ -876,14 +870,12 @@ static struct bfq_queue *bfqq_close(struct bfq_data *bfqd) - /* - * bfqd - obvious - * cur_bfqq - passed in so that we don't decide that the current queue -- * is closely cooperating with itself. -- * -- * We are assuming that cur_bfqq has dispatched at least one request, -- * and that bfqd->last_position reflects a position on the disk associated -- * with the I/O issued by cur_bfqq. -+ * is closely cooperating with itself -+ * sector - used as a reference point to search for a close queue - */ - static struct bfq_queue *bfq_close_cooperator(struct bfq_data *bfqd, -- struct bfq_queue *cur_bfqq) -+ struct bfq_queue *cur_bfqq, -+ sector_t sector) - { - struct bfq_queue *bfqq; - -@@ -903,7 +895,7 @@ static struct bfq_queue *bfq_close_cooperator(struct bfq_data *bfqd, - * working closely on the same area of the disk. In that case, - * we can group them together and don't waste time idling. - */ -- bfqq = bfqq_close(bfqd); -+ bfqq = bfqq_close(bfqd, sector); - if (bfqq == NULL || bfqq == cur_bfqq) - return NULL; - -@@ -930,6 +922,282 @@ static struct bfq_queue *bfq_close_cooperator(struct bfq_data *bfqd, - return bfqq; - } - -+static struct bfq_queue * -+bfq_setup_merge(struct bfq_queue *bfqq, struct bfq_queue *new_bfqq) -+{ -+ int process_refs, new_process_refs; -+ struct bfq_queue *__bfqq; -+ -+ /* -+ * If there are no process references on the new_bfqq, then it is -+ * unsafe to follow the ->new_bfqq chain as other bfqq's in the chain -+ * may have dropped their last reference (not just their last process -+ * reference). -+ */ -+ if (!bfqq_process_refs(new_bfqq)) -+ return NULL; -+ -+ /* Avoid a circular list and skip interim queue merges. */ -+ while ((__bfqq = new_bfqq->new_bfqq)) { -+ if (__bfqq == bfqq) -+ return NULL; -+ new_bfqq = __bfqq; -+ } -+ -+ process_refs = bfqq_process_refs(bfqq); -+ new_process_refs = bfqq_process_refs(new_bfqq); -+ /* -+ * If the process for the bfqq has gone away, there is no -+ * sense in merging the queues. -+ */ -+ if (process_refs == 0 || new_process_refs == 0) -+ return NULL; -+ -+ bfq_log_bfqq(bfqq->bfqd, bfqq, "scheduling merge with queue %d", -+ new_bfqq->pid); -+ -+ /* -+ * Merging is just a redirection: the requests of the process owning -+ * one of the two queues are redirected to the other queue. The latter -+ * queue, in its turn, is set as shared if this is the first time that -+ * the requests of some process are redirected to it. -+ * -+ * We redirect bfqq to new_bfqq and not the opposite, because we -+ * are in the context of the process owning bfqq, hence we have the -+ * io_cq of this process. So we can immediately configure this io_cq -+ * to redirect the requests of the process to new_bfqq. -+ * -+ * NOTE, even if new_bfqq coincides with the in-service queue, the -+ * io_cq of new_bfqq is not available, because, if the in-service queue -+ * is shared, bfqd->in_service_bic may not point to the io_cq of the -+ * in-service queue. -+ * Redirecting the requests of the process owning bfqq to the currently -+ * in-service queue is in any case the best option, as we feed the -+ * in-service queue with new requests close to the last request served -+ * and, by doing so, hopefully increase the throughput. -+ */ -+ bfqq->new_bfqq = new_bfqq; -+ atomic_add(process_refs, &new_bfqq->ref); -+ return new_bfqq; -+} -+ -+/* -+ * Attempt to schedule a merge of bfqq with the currently in-service queue or -+ * with a close queue among the scheduled queues. -+ * Return NULL if no merge was scheduled, a pointer to the shared bfq_queue -+ * structure otherwise. -+ */ -+static struct bfq_queue * -+bfq_setup_cooperator(struct bfq_data *bfqd, struct bfq_queue *bfqq, -+ void *io_struct, bool request) -+{ -+ struct bfq_queue *in_service_bfqq, *new_bfqq; -+ -+ if (bfqq->new_bfqq) -+ return bfqq->new_bfqq; -+ -+ if (!io_struct) -+ return NULL; -+ -+ in_service_bfqq = bfqd->in_service_queue; -+ -+ if (in_service_bfqq == NULL || in_service_bfqq == bfqq || -+ !bfqd->in_service_bic) -+ goto check_scheduled; -+ -+ if (bfq_class_idle(in_service_bfqq) || bfq_class_idle(bfqq)) -+ goto check_scheduled; -+ -+ if (bfq_class_rt(in_service_bfqq) != bfq_class_rt(bfqq)) -+ goto check_scheduled; -+ -+ if (in_service_bfqq->entity.parent != bfqq->entity.parent) -+ goto check_scheduled; -+ -+ if (bfq_rq_close_to_sector(io_struct, request, bfqd->last_position) && -+ bfq_bfqq_sync(in_service_bfqq) && bfq_bfqq_sync(bfqq)) { -+ new_bfqq = bfq_setup_merge(bfqq, in_service_bfqq); -+ if (new_bfqq != NULL) -+ return new_bfqq; /* Merge with the in-service queue */ -+ } -+ -+ /* -+ * Check whether there is a cooperator among currently scheduled -+ * queues. The only thing we need is that the bio/request is not -+ * NULL, as we need it to establish whether a cooperator exists. -+ */ -+check_scheduled: -+ new_bfqq = bfq_close_cooperator(bfqd, bfqq, -+ bfq_io_struct_pos(io_struct, request)); -+ if (new_bfqq) -+ return bfq_setup_merge(bfqq, new_bfqq); -+ -+ return NULL; -+} -+ -+static inline void -+bfq_bfqq_save_state(struct bfq_queue *bfqq) -+{ -+ /* -+ * If bfqq->bic == NULL, the queue is already shared or its requests -+ * have already been redirected to a shared queue; both idle window -+ * and weight raising state have already been saved. Do nothing. -+ */ -+ if (bfqq->bic == NULL) -+ return; -+ if (bfqq->bic->raising_time_left) -+ /* -+ * This is the queue of a just-started process, and would -+ * deserve weight raising: we set raising_time_left to the full -+ * weight-raising duration to trigger weight-raising when and -+ * if the queue is split and the first request of the queue -+ * is enqueued. -+ */ -+ bfqq->bic->raising_time_left = bfq_wrais_duration(bfqq->bfqd); -+ else if (bfqq->raising_coeff > 1) { -+ unsigned long wrais_duration = -+ jiffies - bfqq->last_rais_start_finish; -+ /* -+ * It may happen that a queue's weight raising period lasts -+ * longer than its raising_cur_max_time, as weight raising is -+ * handled only when a request is enqueued or dispatched (it -+ * does not use any timer). If the weight raising period is -+ * about to end, don't save it. -+ */ -+ if (bfqq->raising_cur_max_time <= wrais_duration) -+ bfqq->bic->raising_time_left = 0; -+ else -+ bfqq->bic->raising_time_left = -+ bfqq->raising_cur_max_time - wrais_duration; -+ /* -+ * The bfq_queue is becoming shared or the requests of the -+ * process owning the queue are being redirected to a shared -+ * queue. Stop the weight raising period of the queue, as in -+ * both cases it should not be owned by an interactive or soft -+ * real-time application. -+ */ -+ bfq_bfqq_end_raising(bfqq); -+ } else -+ bfqq->bic->raising_time_left = 0; -+ bfqq->bic->saved_idle_window = bfq_bfqq_idle_window(bfqq); -+} -+ -+static inline void -+bfq_get_bic_reference(struct bfq_queue *bfqq) -+{ -+ /* -+ * If bfqq->bic has a non-NULL value, the bic to which it belongs -+ * is about to begin using a shared bfq_queue. -+ */ -+ if (bfqq->bic) -+ atomic_long_inc(&bfqq->bic->icq.ioc->refcount); -+} -+ -+static void -+bfq_merge_bfqqs(struct bfq_data *bfqd, struct bfq_io_cq *bic, -+ struct bfq_queue *bfqq, struct bfq_queue *new_bfqq) -+{ -+ bfq_log_bfqq(bfqd, bfqq, "merging with queue %lu", -+ (long unsigned)new_bfqq->pid); -+ /* Save weight raising and idle window of the merged queues */ -+ bfq_bfqq_save_state(bfqq); -+ bfq_bfqq_save_state(new_bfqq); -+ /* -+ * Grab a reference to the bic, to prevent it from being destroyed -+ * before being possibly touched by a bfq_split_bfqq(). -+ */ -+ bfq_get_bic_reference(bfqq); -+ bfq_get_bic_reference(new_bfqq); -+ /* Merge queues (that is, let bic redirect its requests to new_bfqq) */ -+ bic_set_bfqq(bic, new_bfqq, 1); -+ bfq_mark_bfqq_coop(new_bfqq); -+ /* -+ * new_bfqq now belongs to at least two bics (it is a shared queue): set -+ * new_bfqq->bic to NULL. bfqq either: -+ * - does not belong to any bic any more, and hence bfqq->bic must -+ * be set to NULL, or -+ * - is a queue whose owning bics have already been redirected to a -+ * different queue, hence the queue is destined to not belong to any -+ * bic soon and bfqq->bic is already NULL (therefore the next -+ * assignment causes no harm). -+ */ -+ new_bfqq->bic = NULL; -+ bfqq->bic = NULL; -+ bfq_put_queue(bfqq); -+} -+ -+static int bfq_allow_merge(struct request_queue *q, struct request *rq, -+ struct bio *bio) -+{ -+ struct bfq_data *bfqd = q->elevator->elevator_data; -+ struct bfq_io_cq *bic; -+ struct bfq_queue *bfqq, *new_bfqq; -+ -+ /* -+ * Disallow merge of a sync bio into an async request. -+ */ -+ if (bfq_bio_sync(bio) && !rq_is_sync(rq)) -+ return 0; -+ -+ /* -+ * Lookup the bfqq that this bio will be queued with. Allow -+ * merge only if rq is queued there. -+ * Queue lock is held here. -+ */ -+ bic = bfq_bic_lookup(bfqd, current->io_context); -+ if (bic == NULL) -+ return 0; -+ -+ bfqq = bic_to_bfqq(bic, bfq_bio_sync(bio)); -+ /* -+ * We take advantage of this function to perform an early merge -+ * of the queues of possible cooperating processes. -+ */ -+ if (bfqq != NULL) { -+ new_bfqq = bfq_setup_cooperator(bfqd, bfqq, bio, false); -+ if (new_bfqq != NULL) { -+ bfq_merge_bfqqs(bfqd, bic, bfqq, new_bfqq); -+ /* -+ * If we get here, the bio will be queued in the shared queue, -+ * i.e., new_bfqq, so use new_bfqq to decide whether bio and -+ * rq can be merged. -+ */ -+ bfqq = new_bfqq; -+ } -+ } -+ -+ return bfqq == RQ_BFQQ(rq); -+} -+ -+static void __bfq_set_in_service_queue(struct bfq_data *bfqd, -+ struct bfq_queue *bfqq) -+{ -+ if (bfqq != NULL) { -+ bfq_mark_bfqq_must_alloc(bfqq); -+ bfq_mark_bfqq_budget_new(bfqq); -+ bfq_clear_bfqq_fifo_expire(bfqq); -+ -+ bfqd->budgets_assigned = (bfqd->budgets_assigned*7 + 256) / 8; -+ -+ bfq_log_bfqq(bfqd, bfqq, -+ "set_in_service_queue, cur-budget = %lu", -+ bfqq->entity.budget); -+ } -+ -+ bfqd->in_service_queue = bfqq; -+} -+ -+/* -+ * Get and set a new queue for service. -+ */ -+static struct bfq_queue *bfq_set_in_service_queue(struct bfq_data *bfqd) -+{ -+ struct bfq_queue *bfqq = bfq_get_next_queue(bfqd); -+ -+ __bfq_set_in_service_queue(bfqd, bfqq); -+ return bfqq; -+} -+ - /* - * If enough samples have been computed, return the current max budget - * stored in bfqd, which is dynamically updated according to the -@@ -1077,63 +1345,6 @@ static struct request *bfq_check_fifo(struct bfq_queue *bfqq) - return rq; - } - --/* -- * Must be called with the queue_lock held. -- */ --static int bfqq_process_refs(struct bfq_queue *bfqq) --{ -- int process_refs, io_refs; -- -- io_refs = bfqq->allocated[READ] + bfqq->allocated[WRITE]; -- process_refs = atomic_read(&bfqq->ref) - io_refs - bfqq->entity.on_st; -- BUG_ON(process_refs < 0); -- return process_refs; --} -- --static void bfq_setup_merge(struct bfq_queue *bfqq, struct bfq_queue *new_bfqq) --{ -- int process_refs, new_process_refs; -- struct bfq_queue *__bfqq; -- -- /* -- * If there are no process references on the new_bfqq, then it is -- * unsafe to follow the ->new_bfqq chain as other bfqq's in the chain -- * may have dropped their last reference (not just their last process -- * reference). -- */ -- if (!bfqq_process_refs(new_bfqq)) -- return; -- -- /* Avoid a circular list and skip interim queue merges. */ -- while ((__bfqq = new_bfqq->new_bfqq)) { -- if (__bfqq == bfqq) -- return; -- new_bfqq = __bfqq; -- } -- -- process_refs = bfqq_process_refs(bfqq); -- new_process_refs = bfqq_process_refs(new_bfqq); -- /* -- * If the process for the bfqq has gone away, there is no -- * sense in merging the queues. -- */ -- if (process_refs == 0 || new_process_refs == 0) -- return; -- -- /* -- * Merge in the direction of the lesser amount of work. -- */ -- if (new_process_refs >= process_refs) { -- bfqq->new_bfqq = new_bfqq; -- atomic_add(process_refs, &new_bfqq->ref); -- } else { -- new_bfqq->new_bfqq = bfqq; -- atomic_add(new_process_refs, &bfqq->ref); -- } -- bfq_log_bfqq(bfqq->bfqd, bfqq, "scheduling merge with queue %d", -- new_bfqq->pid); --} -- - static inline unsigned long bfq_bfqq_budget_left(struct bfq_queue *bfqq) - { - struct bfq_entity *entity = &bfqq->entity; -@@ -1703,7 +1914,7 @@ static inline bool bfq_bfqq_must_idle(struct bfq_queue *bfqq) - */ - static struct bfq_queue *bfq_select_queue(struct bfq_data *bfqd) - { -- struct bfq_queue *bfqq, *new_bfqq = NULL; -+ struct bfq_queue *bfqq; - struct request *next_rq; - enum bfqq_expiration reason = BFQ_BFQQ_BUDGET_TIMEOUT; - -@@ -1713,17 +1924,6 @@ static struct bfq_queue *bfq_select_queue(struct bfq_data *bfqd) - - bfq_log_bfqq(bfqd, bfqq, "select_queue: already in-service queue"); - -- /* -- * If another queue has a request waiting within our mean seek -- * distance, let it run. The expire code will check for close -- * cooperators and put the close queue at the front of the -- * service tree. If possible, merge the expiring queue with the -- * new bfqq. -- */ -- new_bfqq = bfq_close_cooperator(bfqd, bfqq); -- if (new_bfqq != NULL && bfqq->new_bfqq == NULL) -- bfq_setup_merge(bfqq, new_bfqq); -- - if (bfq_may_expire_for_budg_timeout(bfqq) && - !timer_pending(&bfqd->idle_slice_timer) && - !bfq_bfqq_must_idle(bfqq)) -@@ -1760,36 +1960,26 @@ static struct bfq_queue *bfq_select_queue(struct bfq_data *bfqd) - bfq_clear_bfqq_wait_request(bfqq); - del_timer(&bfqd->idle_slice_timer); - } -- if (new_bfqq == NULL) -- goto keep_queue; -- else -- goto expire; -+ goto keep_queue; - } - } - - /* -- * No requests pending. If the in-service queue has no cooperator and -- * still has requests in flight (possibly waiting for a completion) -- * or is idling for a new request, then keep it. -+ * No requests pending. If the in-service queue still has requests in -+ * flight (possibly waiting for a completion) or is idling for a new -+ * request, then keep it. - */ -- if (new_bfqq == NULL && (timer_pending(&bfqd->idle_slice_timer) || -- (bfqq->dispatched != 0 && bfq_bfqq_must_not_expire(bfqq)))) { -+ if (timer_pending(&bfqd->idle_slice_timer) || -+ (bfqq->dispatched != 0 && bfq_bfqq_must_not_expire(bfqq))) { - bfqq = NULL; - goto keep_queue; -- } else if (new_bfqq != NULL && timer_pending(&bfqd->idle_slice_timer)) { -- /* -- * Expiring the queue because there is a close cooperator, -- * cancel timer. -- */ -- bfq_clear_bfqq_wait_request(bfqq); -- del_timer(&bfqd->idle_slice_timer); - } - - reason = BFQ_BFQQ_NO_MORE_REQUESTS; - expire: - bfq_bfqq_expire(bfqd, bfqq, 0, reason); - new_queue: -- bfqq = bfq_set_in_service_queue(bfqd, new_bfqq); -+ bfqq = bfq_set_in_service_queue(bfqd); - bfq_log(bfqd, "select_queue: new queue %d returned", - bfqq != NULL ? bfqq->pid : 0); - keep_queue: -@@ -1799,9 +1989,8 @@ keep_queue: - static void bfq_update_raising_data(struct bfq_data *bfqd, - struct bfq_queue *bfqq) - { -+ struct bfq_entity *entity = &bfqq->entity; - if (bfqq->raising_coeff > 1) { /* queue is being boosted */ -- struct bfq_entity *entity = &bfqq->entity; -- - bfq_log_bfqq(bfqd, bfqq, - "raising period dur %u/%u msec, " - "old raising coeff %u, w %d(%d)", -@@ -1818,7 +2007,7 @@ static void bfq_update_raising_data(struct bfq_data *bfqd, - "WARN: pending prio change"); - /* - * If too much time has elapsed from the beginning -- * of this weight-raising, stop it. -+ * of this weight-raising period, stop it. - */ - if (jiffies - bfqq->last_rais_start_finish > - bfqq->raising_cur_max_time) { -@@ -1830,11 +2019,13 @@ static void bfq_update_raising_data(struct bfq_data *bfqd, - jiffies_to_msecs(bfqq-> - raising_cur_max_time)); - bfq_bfqq_end_raising(bfqq); -- __bfq_entity_update_weight_prio( -- bfq_entity_service_tree(entity), -- entity); - } - } -+ /* Update weight both if it must be raised and if it must be lowered */ -+ if ((entity->weight > entity->orig_weight) != (bfqq->raising_coeff > 1)) -+ __bfq_entity_update_weight_prio( -+ bfq_entity_service_tree(entity), -+ entity); - } - - /* -@@ -2075,6 +2266,25 @@ static void bfq_init_icq(struct io_cq *icq) - struct bfq_io_cq *bic = icq_to_bic(icq); - - bic->ttime.last_end_request = jiffies; -+ /* -+ * A newly created bic indicates that the process has just -+ * started doing I/O, and is probably mapping into memory its -+ * executable and libraries: it definitely needs weight raising. -+ * There is however the possibility that the process performs, -+ * for a while, I/O close to some other process. EQM intercepts -+ * this behavior and may merge the queue corresponding to the -+ * process with some other queue, BEFORE the weight of the queue -+ * is raised. Merged queues are not weight-raised (they are assumed -+ * to belong to processes that benefit only from high throughput). -+ * If the merge is basically the consequence of an accident, then -+ * the queue will be split soon and will get back its old weight. -+ * It is then important to write down somewhere that this queue -+ * does need weight raising, even if it did not make it to get its -+ * weight raised before being merged. To this purpose, we overload -+ * the field raising_time_left and assign 1 to it, to mark the queue -+ * as needing weight raising. -+ */ -+ bic->raising_time_left = 1; - } - - static void bfq_exit_icq(struct io_cq *icq) -@@ -2088,6 +2298,13 @@ static void bfq_exit_icq(struct io_cq *icq) - } - - if (bic->bfqq[BLK_RW_SYNC]) { -+ /* -+ * If the bic is using a shared queue, put the reference -+ * taken on the io_context when the bic started using a -+ * shared bfq_queue. -+ */ -+ if (bfq_bfqq_coop(bic->bfqq[BLK_RW_SYNC])) -+ put_io_context(icq->ioc); - bfq_exit_bfqq(bfqd, bic->bfqq[BLK_RW_SYNC]); - bic->bfqq[BLK_RW_SYNC] = NULL; - } -@@ -2375,6 +2592,10 @@ static void bfq_update_idle_window(struct bfq_data *bfqd, - if (!bfq_bfqq_sync(bfqq) || bfq_class_idle(bfqq)) - return; - -+ /* Idle window just restored, statistics are meaningless. */ -+ if (bfq_bfqq_just_split(bfqq)) -+ return; -+ - enable_idle = bfq_bfqq_idle_window(bfqq); - - if (atomic_read(&bic->icq.ioc->active_ref) == 0 || -@@ -2415,6 +2636,7 @@ static void bfq_rq_enqueued(struct bfq_data *bfqd, struct bfq_queue *bfqq, - if (bfqq->entity.service > bfq_max_budget(bfqd) / 8 || - !BFQQ_SEEKY(bfqq)) - bfq_update_idle_window(bfqd, bfqq, bic); -+ bfq_clear_bfqq_just_split(bfqq); - - bfq_log_bfqq(bfqd, bfqq, - "rq_enqueued: idle_window=%d (seeky %d, mean %llu)", -@@ -2475,13 +2697,48 @@ static void bfq_rq_enqueued(struct bfq_data *bfqd, struct bfq_queue *bfqq, - static void bfq_insert_request(struct request_queue *q, struct request *rq) - { - struct bfq_data *bfqd = q->elevator->elevator_data; -- struct bfq_queue *bfqq = RQ_BFQQ(rq); -+ struct bfq_queue *bfqq = RQ_BFQQ(rq), *new_bfqq; - - assert_spin_locked(bfqd->queue->queue_lock); -+ -+ /* -+ * An unplug may trigger a requeue of a request from the device -+ * driver: make sure we are in process context while trying to -+ * merge two bfq_queues. -+ */ -+ if (!in_interrupt()) { -+ new_bfqq = bfq_setup_cooperator(bfqd, bfqq, rq, true); -+ if (new_bfqq != NULL) { -+ if (bic_to_bfqq(RQ_BIC(rq), 1) != bfqq) -+ new_bfqq = bic_to_bfqq(RQ_BIC(rq), 1); -+ /* -+ * Release the request's reference to the old bfqq -+ * and make sure one is taken to the shared queue. -+ */ -+ new_bfqq->allocated[rq_data_dir(rq)]++; -+ bfqq->allocated[rq_data_dir(rq)]--; -+ atomic_inc(&new_bfqq->ref); -+ bfq_put_queue(bfqq); -+ if (bic_to_bfqq(RQ_BIC(rq), 1) == bfqq) -+ bfq_merge_bfqqs(bfqd, RQ_BIC(rq), -+ bfqq, new_bfqq); -+ rq->elv.priv[1] = new_bfqq; -+ bfqq = new_bfqq; -+ } -+ } -+ - bfq_init_prio_data(bfqq, RQ_BIC(rq)); - - bfq_add_rq_rb(rq); - -+ /* -+ * Here a newly-created bfq_queue has already started a weight-raising -+ * period: clear raising_time_left to prevent bfq_bfqq_save_state() -+ * from assigning it a full weight-raising period. See the detailed -+ * comments about this field in bfq_init_icq(). -+ */ -+ if (bfqq->bic != NULL) -+ bfqq->bic->raising_time_left = 0; - rq_set_fifo_time(rq, jiffies + bfqd->bfq_fifo_expire[rq_is_sync(rq)]); - list_add_tail(&rq->queuelist, &bfqq->fifo); - -@@ -2629,18 +2886,6 @@ static void bfq_put_request(struct request *rq) - } - } - --static struct bfq_queue * --bfq_merge_bfqqs(struct bfq_data *bfqd, struct bfq_io_cq *bic, -- struct bfq_queue *bfqq) --{ -- bfq_log_bfqq(bfqd, bfqq, "merging with queue %lu", -- (long unsigned)bfqq->new_bfqq->pid); -- bic_set_bfqq(bic, bfqq->new_bfqq, 1); -- bfq_mark_bfqq_coop(bfqq->new_bfqq); -- bfq_put_queue(bfqq); -- return bic_to_bfqq(bic, 1); --} -- - /* - * Returns NULL if a new bfqq should be allocated, or the old bfqq if this - * was the last process referring to said bfqq. -@@ -2649,6 +2894,9 @@ static struct bfq_queue * - bfq_split_bfqq(struct bfq_io_cq *bic, struct bfq_queue *bfqq) - { - bfq_log_bfqq(bfqq->bfqd, bfqq, "splitting queue"); -+ -+ put_io_context(bic->icq.ioc); -+ - if (bfqq_process_refs(bfqq) == 1) { - bfqq->pid = current->pid; - bfq_clear_bfqq_coop(bfqq); -@@ -2677,6 +2925,7 @@ static int bfq_set_request(struct request_queue *q, struct request *rq, - struct bfq_queue *bfqq; - struct bfq_group *bfqg; - unsigned long flags; -+ bool split = false; - - might_sleep_if(gfp_mask & __GFP_WAIT); - -@@ -2695,24 +2944,14 @@ new_queue: - bfqq = bfq_get_queue(bfqd, bfqg, is_sync, bic, gfp_mask); - bic_set_bfqq(bic, bfqq, is_sync); - } else { -- /* -- * If the queue was seeky for too long, break it apart. -- */ -+ /* If the queue was seeky for too long, break it apart. */ - if (bfq_bfqq_coop(bfqq) && bfq_bfqq_split_coop(bfqq)) { - bfq_log_bfqq(bfqd, bfqq, "breaking apart bfqq"); - bfqq = bfq_split_bfqq(bic, bfqq); -+ split = true; - if (!bfqq) - goto new_queue; - } -- -- /* -- * Check to see if this queue is scheduled to merge with -- * another closely cooperating queue. The merging of queues -- * happens here as it must be done in process context. -- * The reference on new_bfqq was taken in merge_bfqqs. -- */ -- if (bfqq->new_bfqq != NULL) -- bfqq = bfq_merge_bfqqs(bfqd, bic, bfqq); - } - - bfqq->allocated[rw]++; -@@ -2723,6 +2962,26 @@ new_queue: - rq->elv.priv[0] = bic; - rq->elv.priv[1] = bfqq; - -+ /* -+ * If a bfq_queue has only one process reference, it is owned -+ * by only one bfq_io_cq: we can set the bic field of the -+ * bfq_queue to the address of that structure. Also, if the -+ * queue has just been split, mark a flag so that the -+ * information is available to the other scheduler hooks. -+ */ -+ if (bfqq_process_refs(bfqq) == 1) { -+ bfqq->bic = bic; -+ if (split) { -+ bfq_mark_bfqq_just_split(bfqq); -+ /* -+ * If the queue has just been split from a shared queue, -+ * restore the idle window and the possible weight -+ * raising period. -+ */ -+ bfq_bfqq_resume_state(bfqq, bic); -+ } -+ } -+ - spin_unlock_irqrestore(q->queue_lock, flags); - - return 0; -diff --git a/block/bfq-sched.c b/block/bfq-sched.c -index 30df81c..47e66a8 100644 ---- a/block/bfq-sched.c -+++ b/block/bfq-sched.c -@@ -979,34 +979,6 @@ static struct bfq_queue *bfq_get_next_queue(struct bfq_data *bfqd) - return bfqq; - } - --/* -- * Forced extraction of the given queue. -- */ --static void bfq_get_next_queue_forced(struct bfq_data *bfqd, -- struct bfq_queue *bfqq) --{ -- struct bfq_entity *entity; -- struct bfq_sched_data *sd; -- -- BUG_ON(bfqd->in_service_queue != NULL); -- -- entity = &bfqq->entity; -- /* -- * Bubble up extraction/update from the leaf to the root. -- */ -- for_each_entity(entity) { -- sd = entity->sched_data; -- bfq_update_budget(entity); -- bfq_update_vtime(bfq_entity_service_tree(entity)); -- bfq_active_extract(bfq_entity_service_tree(entity), entity); -- sd->active_entity = entity; -- sd->next_active = NULL; -- entity->service = 0; -- } -- -- return; --} -- - static void __bfq_bfqd_reset_in_service(struct bfq_data *bfqd) - { - if (bfqd->in_service_bic != NULL) { -diff --git a/block/bfq.h b/block/bfq.h -index 78da7d2..b6ebc1d 100644 ---- a/block/bfq.h -+++ b/block/bfq.h -@@ -192,6 +192,8 @@ struct bfq_group; - * idle to backlogged - * @service_from_backlogged: cumulative service received from the @bfq_queue - * since the last transition from idle to backlogged -+ * @bic: pointer to the bfq_io_cq owning the bfq_queue, set to %NULL if the -+ * queue is shared - * - * A bfq_queue is a leaf request queue; it can be associated to an io_context - * or more (if it is an async one). @cgroup holds a reference to the -@@ -235,6 +237,7 @@ struct bfq_queue { - sector_t last_request_pos; - - pid_t pid; -+ struct bfq_io_cq *bic; - - /* weight-raising fields */ - unsigned int raising_cur_max_time; -@@ -264,12 +267,23 @@ struct bfq_ttime { - * @icq: associated io_cq structure - * @bfqq: array of two process queues, the sync and the async - * @ttime: associated @bfq_ttime struct -+ * @raising_time_left: snapshot of the time left before weight raising ends -+ * for the sync queue associated to this process; this -+ * snapshot is taken to remember this value while the weight -+ * raising is suspended because the queue is merged with a -+ * shared queue, and is used to set @raising_cur_max_time -+ * when the queue is split from the shared queue and its -+ * weight is raised again -+ * @saved_idle_window: same purpose as the previous field for the idle window - */ - struct bfq_io_cq { - struct io_cq icq; /* must be the first member */ - struct bfq_queue *bfqq[2]; - struct bfq_ttime ttime; - int ioprio; -+ -+ unsigned int raising_time_left; -+ unsigned int saved_idle_window; - }; - - /** -@@ -411,6 +425,7 @@ enum bfqq_state_flags { - BFQ_BFQQ_FLAG_budget_new, /* no completion with this budget */ - BFQ_BFQQ_FLAG_coop, /* bfqq is shared */ - BFQ_BFQQ_FLAG_split_coop, /* shared bfqq will be splitted */ -+ BFQ_BFQQ_FLAG_just_split, /* queue has just been split */ - BFQ_BFQQ_FLAG_softrt_update, /* needs softrt-next-start update */ - }; - -@@ -438,6 +453,7 @@ BFQ_BFQQ_FNS(sync); - BFQ_BFQQ_FNS(budget_new); - BFQ_BFQQ_FNS(coop); - BFQ_BFQQ_FNS(split_coop); -+BFQ_BFQQ_FNS(just_split); - BFQ_BFQQ_FNS(softrt_update); - #undef BFQ_BFQQ_FNS - --- -1.8.5.2 - diff --git a/sys-kernel/kogaion-sources/files/desktop/3.10-ck1.patch b/sys-kernel/kogaion-sources/files/desktop/3.10-ck1.patch deleted file mode 100644 index 1a9feb96..00000000 --- a/sys-kernel/kogaion-sources/files/desktop/3.10-ck1.patch +++ /dev/null @@ -1,8732 +0,0 @@ -// patch-3.10-ck1.patch -Index: linux-3.10-ck1/arch/powerpc/platforms/cell/spufs/sched.c -=================================================================== ---- linux-3.10-ck1.orig/arch/powerpc/platforms/cell/spufs/sched.c 2013-07-09 17:28:57.209502080 +1000 -+++ linux-3.10-ck1/arch/powerpc/platforms/cell/spufs/sched.c 2013-07-09 17:29:00.837501924 +1000 -@@ -64,11 +64,6 @@ - static struct timer_list spuloadavg_timer; - - /* -- * Priority of a normal, non-rt, non-niced'd process (aka nice level 0). -- */ --#define NORMAL_PRIO 120 -- --/* - * Frequency of the spu scheduler tick. By default we do one SPU scheduler - * tick for every 10 CPU scheduler ticks. - */ -Index: linux-3.10-ck1/Documentation/scheduler/sched-BFS.txt -=================================================================== ---- /dev/null 1970-01-01 00:00:00.000000000 +0000 -+++ linux-3.10-ck1/Documentation/scheduler/sched-BFS.txt 2013-07-09 17:29:00.837501924 +1000 -@@ -0,0 +1,347 @@ -+BFS - The Brain Fuck Scheduler by Con Kolivas. -+ -+Goals. -+ -+The goal of the Brain Fuck Scheduler, referred to as BFS from here on, is to -+completely do away with the complex designs of the past for the cpu process -+scheduler and instead implement one that is very simple in basic design. -+The main focus of BFS is to achieve excellent desktop interactivity and -+responsiveness without heuristics and tuning knobs that are difficult to -+understand, impossible to model and predict the effect of, and when tuned to -+one workload cause massive detriment to another. -+ -+ -+Design summary. -+ -+BFS is best described as a single runqueue, O(n) lookup, earliest effective -+virtual deadline first design, loosely based on EEVDF (earliest eligible virtual -+deadline first) and my previous Staircase Deadline scheduler. Each component -+shall be described in order to understand the significance of, and reasoning for -+it. The codebase when the first stable version was released was approximately -+9000 lines less code than the existing mainline linux kernel scheduler (in -+2.6.31). This does not even take into account the removal of documentation and -+the cgroups code that is not used. -+ -+Design reasoning. -+ -+The single runqueue refers to the queued but not running processes for the -+entire system, regardless of the number of CPUs. The reason for going back to -+a single runqueue design is that once multiple runqueues are introduced, -+per-CPU or otherwise, there will be complex interactions as each runqueue will -+be responsible for the scheduling latency and fairness of the tasks only on its -+own runqueue, and to achieve fairness and low latency across multiple CPUs, any -+advantage in throughput of having CPU local tasks causes other disadvantages. -+This is due to requiring a very complex balancing system to at best achieve some -+semblance of fairness across CPUs and can only maintain relatively low latency -+for tasks bound to the same CPUs, not across them. To increase said fairness -+and latency across CPUs, the advantage of local runqueue locking, which makes -+for better scalability, is lost due to having to grab multiple locks. -+ -+A significant feature of BFS is that all accounting is done purely based on CPU -+used and nowhere is sleep time used in any way to determine entitlement or -+interactivity. Interactivity "estimators" that use some kind of sleep/run -+algorithm are doomed to fail to detect all interactive tasks, and to falsely tag -+tasks that aren't interactive as being so. The reason for this is that it is -+close to impossible to determine that when a task is sleeping, whether it is -+doing it voluntarily, as in a userspace application waiting for input in the -+form of a mouse click or otherwise, or involuntarily, because it is waiting for -+another thread, process, I/O, kernel activity or whatever. Thus, such an -+estimator will introduce corner cases, and more heuristics will be required to -+cope with those corner cases, introducing more corner cases and failed -+interactivity detection and so on. Interactivity in BFS is built into the design -+by virtue of the fact that tasks that are waking up have not used up their quota -+of CPU time, and have earlier effective deadlines, thereby making it very likely -+they will preempt any CPU bound task of equivalent nice level. See below for -+more information on the virtual deadline mechanism. Even if they do not preempt -+a running task, because the rr interval is guaranteed to have a bound upper -+limit on how long a task will wait for, it will be scheduled within a timeframe -+that will not cause visible interface jitter. -+ -+ -+Design details. -+ -+Task insertion. -+ -+BFS inserts tasks into each relevant queue as an O(1) insertion into a double -+linked list. On insertion, *every* running queue is checked to see if the newly -+queued task can run on any idle queue, or preempt the lowest running task on the -+system. This is how the cross-CPU scheduling of BFS achieves significantly lower -+latency per extra CPU the system has. In this case the lookup is, in the worst -+case scenario, O(n) where n is the number of CPUs on the system. -+ -+Data protection. -+ -+BFS has one single lock protecting the process local data of every task in the -+global queue. Thus every insertion, removal and modification of task data in the -+global runqueue needs to grab the global lock. However, once a task is taken by -+a CPU, the CPU has its own local data copy of the running process' accounting -+information which only that CPU accesses and modifies (such as during a -+timer tick) thus allowing the accounting data to be updated lockless. Once a -+CPU has taken a task to run, it removes it from the global queue. Thus the -+global queue only ever has, at most, -+ -+ (number of tasks requesting cpu time) - (number of logical CPUs) + 1 -+ -+tasks in the global queue. This value is relevant for the time taken to look up -+tasks during scheduling. This will increase if many tasks with CPU affinity set -+in their policy to limit which CPUs they're allowed to run on if they outnumber -+the number of CPUs. The +1 is because when rescheduling a task, the CPU's -+currently running task is put back on the queue. Lookup will be described after -+the virtual deadline mechanism is explained. -+ -+Virtual deadline. -+ -+The key to achieving low latency, scheduling fairness, and "nice level" -+distribution in BFS is entirely in the virtual deadline mechanism. The one -+tunable in BFS is the rr_interval, or "round robin interval". This is the -+maximum time two SCHED_OTHER (or SCHED_NORMAL, the common scheduling policy) -+tasks of the same nice level will be running for, or looking at it the other -+way around, the longest duration two tasks of the same nice level will be -+delayed for. When a task requests cpu time, it is given a quota (time_slice) -+equal to the rr_interval and a virtual deadline. The virtual deadline is -+offset from the current time in jiffies by this equation: -+ -+ jiffies + (prio_ratio * rr_interval) -+ -+The prio_ratio is determined as a ratio compared to the baseline of nice -20 -+and increases by 10% per nice level. The deadline is a virtual one only in that -+no guarantee is placed that a task will actually be scheduled by this time, but -+it is used to compare which task should go next. There are three components to -+how a task is next chosen. First is time_slice expiration. If a task runs out -+of its time_slice, it is descheduled, the time_slice is refilled, and the -+deadline reset to that formula above. Second is sleep, where a task no longer -+is requesting CPU for whatever reason. The time_slice and deadline are _not_ -+adjusted in this case and are just carried over for when the task is next -+scheduled. Third is preemption, and that is when a newly waking task is deemed -+higher priority than a currently running task on any cpu by virtue of the fact -+that it has an earlier virtual deadline than the currently running task. The -+earlier deadline is the key to which task is next chosen for the first and -+second cases. Once a task is descheduled, it is put back on the queue, and an -+O(n) lookup of all queued-but-not-running tasks is done to determine which has -+the earliest deadline and that task is chosen to receive CPU next. -+ -+The CPU proportion of different nice tasks works out to be approximately the -+ -+ (prio_ratio difference)^2 -+ -+The reason it is squared is that a task's deadline does not change while it is -+running unless it runs out of time_slice. Thus, even if the time actually -+passes the deadline of another task that is queued, it will not get CPU time -+unless the current running task deschedules, and the time "base" (jiffies) is -+constantly moving. -+ -+Task lookup. -+ -+BFS has 103 priority queues. 100 of these are dedicated to the static priority -+of realtime tasks, and the remaining 3 are, in order of best to worst priority, -+SCHED_ISO (isochronous), SCHED_NORMAL, and SCHED_IDLEPRIO (idle priority -+scheduling). When a task of these priorities is queued, a bitmap of running -+priorities is set showing which of these priorities has tasks waiting for CPU -+time. When a CPU is made to reschedule, the lookup for the next task to get -+CPU time is performed in the following way: -+ -+First the bitmap is checked to see what static priority tasks are queued. If -+any realtime priorities are found, the corresponding queue is checked and the -+first task listed there is taken (provided CPU affinity is suitable) and lookup -+is complete. If the priority corresponds to a SCHED_ISO task, they are also -+taken in FIFO order (as they behave like SCHED_RR). If the priority corresponds -+to either SCHED_NORMAL or SCHED_IDLEPRIO, then the lookup becomes O(n). At this -+stage, every task in the runlist that corresponds to that priority is checked -+to see which has the earliest set deadline, and (provided it has suitable CPU -+affinity) it is taken off the runqueue and given the CPU. If a task has an -+expired deadline, it is taken and the rest of the lookup aborted (as they are -+chosen in FIFO order). -+ -+Thus, the lookup is O(n) in the worst case only, where n is as described -+earlier, as tasks may be chosen before the whole task list is looked over. -+ -+ -+Scalability. -+ -+The major limitations of BFS will be that of scalability, as the separate -+runqueue designs will have less lock contention as the number of CPUs rises. -+However they do not scale linearly even with separate runqueues as multiple -+runqueues will need to be locked concurrently on such designs to be able to -+achieve fair CPU balancing, to try and achieve some sort of nice-level fairness -+across CPUs, and to achieve low enough latency for tasks on a busy CPU when -+other CPUs would be more suited. BFS has the advantage that it requires no -+balancing algorithm whatsoever, as balancing occurs by proxy simply because -+all CPUs draw off the global runqueue, in priority and deadline order. Despite -+the fact that scalability is _not_ the prime concern of BFS, it both shows very -+good scalability to smaller numbers of CPUs and is likely a more scalable design -+at these numbers of CPUs. -+ -+It also has some very low overhead scalability features built into the design -+when it has been deemed their overhead is so marginal that they're worth adding. -+The first is the local copy of the running process' data to the CPU it's running -+on to allow that data to be updated lockless where possible. Then there is -+deference paid to the last CPU a task was running on, by trying that CPU first -+when looking for an idle CPU to use the next time it's scheduled. Finally there -+is the notion of "sticky" tasks that are flagged when they are involuntarily -+descheduled, meaning they still want further CPU time. This sticky flag is -+used to bias heavily against those tasks being scheduled on a different CPU -+unless that CPU would be otherwise idle. When a cpu frequency governor is used -+that scales with CPU load, such as ondemand, sticky tasks are not scheduled -+on a different CPU at all, preferring instead to go idle. This means the CPU -+they were bound to is more likely to increase its speed while the other CPU -+will go idle, thus speeding up total task execution time and likely decreasing -+power usage. This is the only scenario where BFS will allow a CPU to go idle -+in preference to scheduling a task on the earliest available spare CPU. -+ -+The real cost of migrating a task from one CPU to another is entirely dependant -+on the cache footprint of the task, how cache intensive the task is, how long -+it's been running on that CPU to take up the bulk of its cache, how big the CPU -+cache is, how fast and how layered the CPU cache is, how fast a context switch -+is... and so on. In other words, it's close to random in the real world where we -+do more than just one sole workload. The only thing we can be sure of is that -+it's not free. So BFS uses the principle that an idle CPU is a wasted CPU and -+utilising idle CPUs is more important than cache locality, and cache locality -+only plays a part after that. -+ -+When choosing an idle CPU for a waking task, the cache locality is determined -+according to where the task last ran and then idle CPUs are ranked from best -+to worst to choose the most suitable idle CPU based on cache locality, NUMA -+node locality and hyperthread sibling business. They are chosen in the -+following preference (if idle): -+ -+* Same core, idle or busy cache, idle threads -+* Other core, same cache, idle or busy cache, idle threads. -+* Same node, other CPU, idle cache, idle threads. -+* Same node, other CPU, busy cache, idle threads. -+* Same core, busy threads. -+* Other core, same cache, busy threads. -+* Same node, other CPU, busy threads. -+* Other node, other CPU, idle cache, idle threads. -+* Other node, other CPU, busy cache, idle threads. -+* Other node, other CPU, busy threads. -+ -+This shows the SMT or "hyperthread" awareness in the design as well which will -+choose a real idle core first before a logical SMT sibling which already has -+tasks on the physical CPU. -+ -+Early benchmarking of BFS suggested scalability dropped off at the 16 CPU mark. -+However this benchmarking was performed on an earlier design that was far less -+scalable than the current one so it's hard to know how scalable it is in terms -+of both CPUs (due to the global runqueue) and heavily loaded machines (due to -+O(n) lookup) at this stage. Note that in terms of scalability, the number of -+_logical_ CPUs matters, not the number of _physical_ CPUs. Thus, a dual (2x) -+quad core (4X) hyperthreaded (2X) machine is effectively a 16X. Newer benchmark -+results are very promising indeed, without needing to tweak any knobs, features -+or options. Benchmark contributions are most welcome. -+ -+ -+Features -+ -+As the initial prime target audience for BFS was the average desktop user, it -+was designed to not need tweaking, tuning or have features set to obtain benefit -+from it. Thus the number of knobs and features has been kept to an absolute -+minimum and should not require extra user input for the vast majority of cases. -+There are precisely 2 tunables, and 2 extra scheduling policies. The rr_interval -+and iso_cpu tunables, and the SCHED_ISO and SCHED_IDLEPRIO policies. In addition -+to this, BFS also uses sub-tick accounting. What BFS does _not_ now feature is -+support for CGROUPS. The average user should neither need to know what these -+are, nor should they need to be using them to have good desktop behaviour. -+ -+rr_interval -+ -+There is only one "scheduler" tunable, the round robin interval. This can be -+accessed in -+ -+ /proc/sys/kernel/rr_interval -+ -+The value is in milliseconds, and the default value is set to 6ms. Valid values -+are from 1 to 1000. Decreasing the value will decrease latencies at the cost of -+decreasing throughput, while increasing it will improve throughput, but at the -+cost of worsening latencies. The accuracy of the rr interval is limited by HZ -+resolution of the kernel configuration. Thus, the worst case latencies are -+usually slightly higher than this actual value. BFS uses "dithering" to try and -+minimise the effect the Hz limitation has. The default value of 6 is not an -+arbitrary one. It is based on the fact that humans can detect jitter at -+approximately 7ms, so aiming for much lower latencies is pointless under most -+circumstances. It is worth noting this fact when comparing the latency -+performance of BFS to other schedulers. Worst case latencies being higher than -+7ms are far worse than average latencies not being in the microsecond range. -+Experimentation has shown that rr intervals being increased up to 300 can -+improve throughput but beyond that, scheduling noise from elsewhere prevents -+further demonstrable throughput. -+ -+Isochronous scheduling. -+ -+Isochronous scheduling is a unique scheduling policy designed to provide -+near-real-time performance to unprivileged (ie non-root) users without the -+ability to starve the machine indefinitely. Isochronous tasks (which means -+"same time") are set using, for example, the schedtool application like so: -+ -+ schedtool -I -e amarok -+ -+This will start the audio application "amarok" as SCHED_ISO. How SCHED_ISO works -+is that it has a priority level between true realtime tasks and SCHED_NORMAL -+which would allow them to preempt all normal tasks, in a SCHED_RR fashion (ie, -+if multiple SCHED_ISO tasks are running, they purely round robin at rr_interval -+rate). However if ISO tasks run for more than a tunable finite amount of time, -+they are then demoted back to SCHED_NORMAL scheduling. This finite amount of -+time is the percentage of _total CPU_ available across the machine, configurable -+as a percentage in the following "resource handling" tunable (as opposed to a -+scheduler tunable): -+ -+ /proc/sys/kernel/iso_cpu -+ -+and is set to 70% by default. It is calculated over a rolling 5 second average -+Because it is the total CPU available, it means that on a multi CPU machine, it -+is possible to have an ISO task running as realtime scheduling indefinitely on -+just one CPU, as the other CPUs will be available. Setting this to 100 is the -+equivalent of giving all users SCHED_RR access and setting it to 0 removes the -+ability to run any pseudo-realtime tasks. -+ -+A feature of BFS is that it detects when an application tries to obtain a -+realtime policy (SCHED_RR or SCHED_FIFO) and the caller does not have the -+appropriate privileges to use those policies. When it detects this, it will -+give the task SCHED_ISO policy instead. Thus it is transparent to the user. -+Because some applications constantly set their policy as well as their nice -+level, there is potential for them to undo the override specified by the user -+on the command line of setting the policy to SCHED_ISO. To counter this, once -+a task has been set to SCHED_ISO policy, it needs superuser privileges to set -+it back to SCHED_NORMAL. This will ensure the task remains ISO and all child -+processes and threads will also inherit the ISO policy. -+ -+Idleprio scheduling. -+ -+Idleprio scheduling is a scheduling policy designed to give out CPU to a task -+_only_ when the CPU would be otherwise idle. The idea behind this is to allow -+ultra low priority tasks to be run in the background that have virtually no -+effect on the foreground tasks. This is ideally suited to distributed computing -+clients (like setiathome, folding, mprime etc) but can also be used to start -+a video encode or so on without any slowdown of other tasks. To avoid this -+policy from grabbing shared resources and holding them indefinitely, if it -+detects a state where the task is waiting on I/O, the machine is about to -+suspend to ram and so on, it will transiently schedule them as SCHED_NORMAL. As -+per the Isochronous task management, once a task has been scheduled as IDLEPRIO, -+it cannot be put back to SCHED_NORMAL without superuser privileges. Tasks can -+be set to start as SCHED_IDLEPRIO with the schedtool command like so: -+ -+ schedtool -D -e ./mprime -+ -+Subtick accounting. -+ -+It is surprisingly difficult to get accurate CPU accounting, and in many cases, -+the accounting is done by simply determining what is happening at the precise -+moment a timer tick fires off. This becomes increasingly inaccurate as the -+timer tick frequency (HZ) is lowered. It is possible to create an application -+which uses almost 100% CPU, yet by being descheduled at the right time, records -+zero CPU usage. While the main problem with this is that there are possible -+security implications, it is also difficult to determine how much CPU a task -+really does use. BFS tries to use the sub-tick accounting from the TSC clock, -+where possible, to determine real CPU usage. This is not entirely reliable, but -+is far more likely to produce accurate CPU usage data than the existing designs -+and will not show tasks as consuming no CPU usage when they actually are. Thus, -+the amount of CPU reported as being used by BFS will more accurately represent -+how much CPU the task itself is using (as is shown for example by the 'time' -+application), so the reported values may be quite different to other schedulers. -+Values reported as the 'load' are more prone to problems with this design, but -+per process values are closer to real usage. When comparing throughput of BFS -+to other designs, it is important to compare the actual completed work in terms -+of total wall clock time taken and total work done, rather than the reported -+"cpu usage". -+ -+ -+Con Kolivas Tue, 5 Apr 2011 -Index: linux-3.10-ck1/Documentation/sysctl/kernel.txt -=================================================================== ---- linux-3.10-ck1.orig/Documentation/sysctl/kernel.txt 2013-07-09 17:28:57.123502084 +1000 -+++ linux-3.10-ck1/Documentation/sysctl/kernel.txt 2013-07-09 17:29:00.837501924 +1000 -@@ -33,6 +33,7 @@ - - domainname - - hostname - - hotplug -+- iso_cpu - - kptr_restrict - - kstack_depth_to_print [ X86 only ] - - l2cr [ PPC only ] -@@ -60,6 +61,7 @@ - - randomize_va_space - - real-root-dev ==> Documentation/initrd.txt - - reboot-cmd [ SPARC only ] -+- rr_interval - - rtsig-max - - rtsig-nr - - sem -@@ -306,6 +308,16 @@ - - ============================================================== - -+iso_cpu: (BFS CPU scheduler only). -+ -+This sets the percentage cpu that the unprivileged SCHED_ISO tasks can -+run effectively at realtime priority, averaged over a rolling five -+seconds over the -whole- system, meaning all cpus. -+ -+Set to 70 (percent) by default. -+ -+============================================================== -+ - l2cr: (PPC only) - - This flag controls the L2 cache of G3 processor boards. If -@@ -538,6 +550,20 @@ - - ============================================================== - -+rr_interval: (BFS CPU scheduler only) -+ -+This is the smallest duration that any cpu process scheduling unit -+will run for. Increasing this value can increase throughput of cpu -+bound tasks substantially but at the expense of increased latencies -+overall. Conversely decreasing it will decrease average and maximum -+latencies but at the expense of throughput. This value is in -+milliseconds and the default value chosen depends on the number of -+cpus available at scheduler initialisation with a minimum of 6. -+ -+Valid values are from 1-1000. -+ -+============================================================== -+ - rtsig-max & rtsig-nr: - - The file rtsig-max can be used to tune the maximum number -Index: linux-3.10-ck1/fs/proc/base.c -=================================================================== ---- linux-3.10-ck1.orig/fs/proc/base.c 2013-07-09 17:28:57.169502082 +1000 -+++ linux-3.10-ck1/fs/proc/base.c 2013-07-09 17:29:00.838501924 +1000 -@@ -339,7 +339,7 @@ - static int proc_pid_schedstat(struct task_struct *task, char *buffer) - { - return sprintf(buffer, "%llu %llu %lu\n", -- (unsigned long long)task->se.sum_exec_runtime, -+ (unsigned long long)tsk_seruntime(task), - (unsigned long long)task->sched_info.run_delay, - task->sched_info.pcount); - } -Index: linux-3.10-ck1/include/linux/init_task.h -=================================================================== ---- linux-3.10-ck1.orig/include/linux/init_task.h 2013-07-09 17:28:57.154502083 +1000 -+++ linux-3.10-ck1/include/linux/init_task.h 2013-07-09 17:29:00.838501924 +1000 -@@ -152,12 +152,70 @@ - # define INIT_VTIME(tsk) - #endif - --#define INIT_TASK_COMM "swapper" -- - /* - * INIT_TASK is used to set up the first task table, touch at - * your own risk!. Base=0, limit=0x1fffff (=2MB) - */ -+#ifdef CONFIG_SCHED_BFS -+#define INIT_TASK_COMM "BFS" -+#define INIT_TASK(tsk) \ -+{ \ -+ .state = 0, \ -+ .stack = &init_thread_info, \ -+ .usage = ATOMIC_INIT(2), \ -+ .flags = PF_KTHREAD, \ -+ .prio = NORMAL_PRIO, \ -+ .static_prio = MAX_PRIO-20, \ -+ .normal_prio = NORMAL_PRIO, \ -+ .deadline = 0, \ -+ .policy = SCHED_NORMAL, \ -+ .cpus_allowed = CPU_MASK_ALL, \ -+ .mm = NULL, \ -+ .active_mm = &init_mm, \ -+ .run_list = LIST_HEAD_INIT(tsk.run_list), \ -+ .time_slice = HZ, \ -+ .tasks = LIST_HEAD_INIT(tsk.tasks), \ -+ INIT_PUSHABLE_TASKS(tsk) \ -+ .ptraced = LIST_HEAD_INIT(tsk.ptraced), \ -+ .ptrace_entry = LIST_HEAD_INIT(tsk.ptrace_entry), \ -+ .real_parent = &tsk, \ -+ .parent = &tsk, \ -+ .children = LIST_HEAD_INIT(tsk.children), \ -+ .sibling = LIST_HEAD_INIT(tsk.sibling), \ -+ .group_leader = &tsk, \ -+ RCU_POINTER_INITIALIZER(real_cred, &init_cred), \ -+ RCU_POINTER_INITIALIZER(cred, &init_cred), \ -+ .comm = INIT_TASK_COMM, \ -+ .thread = INIT_THREAD, \ -+ .fs = &init_fs, \ -+ .files = &init_files, \ -+ .signal = &init_signals, \ -+ .sighand = &init_sighand, \ -+ .nsproxy = &init_nsproxy, \ -+ .pending = { \ -+ .list = LIST_HEAD_INIT(tsk.pending.list), \ -+ .signal = {{0}}}, \ -+ .blocked = {{0}}, \ -+ .alloc_lock = __SPIN_LOCK_UNLOCKED(tsk.alloc_lock), \ -+ .journal_info = NULL, \ -+ .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \ -+ .pi_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock), \ -+ .timer_slack_ns = 50000, /* 50 usec default slack */ \ -+ .pids = { \ -+ [PIDTYPE_PID] = INIT_PID_LINK(PIDTYPE_PID), \ -+ [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID), \ -+ [PIDTYPE_SID] = INIT_PID_LINK(PIDTYPE_SID), \ -+ }, \ -+ INIT_IDS \ -+ INIT_PERF_EVENTS(tsk) \ -+ INIT_TRACE_IRQFLAGS \ -+ INIT_LOCKDEP \ -+ INIT_FTRACE_GRAPH \ -+ INIT_TRACE_RECURSION \ -+ INIT_TASK_RCU_PREEMPT(tsk) \ -+} -+#else /* CONFIG_SCHED_BFS */ -+#define INIT_TASK_COMM "swapper" - #define INIT_TASK(tsk) \ - { \ - .state = 0, \ -@@ -223,7 +281,7 @@ - INIT_CPUSET_SEQ \ - INIT_VTIME(tsk) \ - } -- -+#endif /* CONFIG_SCHED_BFS */ - - #define INIT_CPU_TIMERS(cpu_timers) \ - { \ -Index: linux-3.10-ck1/include/linux/ioprio.h -=================================================================== ---- linux-3.10-ck1.orig/include/linux/ioprio.h 2013-07-09 17:28:57.146502083 +1000 -+++ linux-3.10-ck1/include/linux/ioprio.h 2013-07-09 17:29:00.838501924 +1000 -@@ -52,6 +52,8 @@ - */ - static inline int task_nice_ioprio(struct task_struct *task) - { -+ if (iso_task(task)) -+ return 0; - return (task_nice(task) + 20) / 5; - } - -Index: linux-3.10-ck1/include/linux/sched.h -=================================================================== ---- linux-3.10-ck1.orig/include/linux/sched.h 2013-07-09 17:28:57.163502082 +1000 -+++ linux-3.10-ck1/include/linux/sched.h 2013-07-09 17:29:00.839501924 +1000 -@@ -229,8 +229,6 @@ - extern void init_idle(struct task_struct *idle, int cpu); - extern void init_idle_bootup_task(struct task_struct *idle); - --extern int runqueue_is_locked(int cpu); -- - #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) - extern void nohz_balance_enter_idle(int cpu); - extern void set_cpu_sd_state_idle(void); -@@ -1040,18 +1038,35 @@ - - #ifdef CONFIG_SMP - struct llist_node wake_entry; -- int on_cpu; - #endif -- int on_rq; -+#if defined(CONFIG_SMP) || defined(CONFIG_SCHED_BFS) -+ bool on_cpu; -+#endif -+#ifndef CONFIG_SCHED_BFS -+ bool on_rq; -+#endif - - int prio, static_prio, normal_prio; - unsigned int rt_priority; -+#ifdef CONFIG_SCHED_BFS -+ int time_slice; -+ u64 deadline; -+ struct list_head run_list; -+ u64 last_ran; -+ u64 sched_time; /* sched_clock time spent running */ -+#ifdef CONFIG_SMP -+ bool sticky; /* Soft affined flag */ -+#endif -+ unsigned long rt_timeout; -+#else /* CONFIG_SCHED_BFS */ - const struct sched_class *sched_class; - struct sched_entity se; - struct sched_rt_entity rt; -+ - #ifdef CONFIG_CGROUP_SCHED - struct task_group *sched_task_group; - #endif -+#endif - - #ifdef CONFIG_PREEMPT_NOTIFIERS - /* list of struct preempt_notifier: */ -@@ -1162,6 +1177,9 @@ - int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */ - - cputime_t utime, stime, utimescaled, stimescaled; -+#ifdef CONFIG_SCHED_BFS -+ unsigned long utime_pc, stime_pc; -+#endif - cputime_t gtime; - #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE - struct cputime prev_cputime; -@@ -1418,6 +1436,64 @@ - #endif - }; - -+#ifdef CONFIG_SCHED_BFS -+bool grunqueue_is_locked(void); -+void grq_unlock_wait(void); -+void cpu_scaling(int cpu); -+void cpu_nonscaling(int cpu); -+bool above_background_load(void); -+#define tsk_seruntime(t) ((t)->sched_time) -+#define tsk_rttimeout(t) ((t)->rt_timeout) -+ -+static inline void tsk_cpus_current(struct task_struct *p) -+{ -+} -+ -+static inline int runqueue_is_locked(int cpu) -+{ -+ return grunqueue_is_locked(); -+} -+ -+void print_scheduler_version(void); -+ -+static inline bool iso_task(struct task_struct *p) -+{ -+ return (p->policy == SCHED_ISO); -+} -+#else /* CFS */ -+extern int runqueue_is_locked(int cpu); -+static inline void cpu_scaling(int cpu) -+{ -+} -+ -+static inline void cpu_nonscaling(int cpu) -+{ -+} -+#define tsk_seruntime(t) ((t)->se.sum_exec_runtime) -+#define tsk_rttimeout(t) ((t)->rt.timeout) -+ -+static inline void tsk_cpus_current(struct task_struct *p) -+{ -+ p->nr_cpus_allowed = current->nr_cpus_allowed; -+} -+ -+static inline void print_scheduler_version(void) -+{ -+ printk(KERN_INFO"CFS CPU scheduler.\n"); -+} -+ -+static inline bool iso_task(struct task_struct *p) -+{ -+ return false; -+} -+ -+/* Anyone feel like implementing this? */ -+static inline bool above_background_load(void) -+{ -+ return false; -+} -+#endif /* CONFIG_SCHED_BFS */ -+ - /* Future-safe accessor for struct task_struct's cpus_allowed. */ - #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) - -@@ -1844,7 +1920,7 @@ - task_sched_runtime(struct task_struct *task); - - /* sched_exec is called by processes performing an exec */ --#ifdef CONFIG_SMP -+#if defined(CONFIG_SMP) && !defined(CONFIG_SCHED_BFS) - extern void sched_exec(void); - #else - #define sched_exec() {} -@@ -2549,7 +2625,7 @@ - return 0; - } - --static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) -+static inline void set_task_cpu(struct task_struct *p, int cpu) - { - } - -Index: linux-3.10-ck1/init/Kconfig -=================================================================== ---- linux-3.10-ck1.orig/init/Kconfig 2013-07-09 17:28:57.132502084 +1000 -+++ linux-3.10-ck1/init/Kconfig 2013-07-09 17:29:00.839501924 +1000 -@@ -28,6 +28,20 @@ - - menu "General setup" - -+config SCHED_BFS -+ bool "BFS cpu scheduler" -+ ---help--- -+ The Brain Fuck CPU Scheduler for excellent interactivity and -+ responsiveness on the desktop and solid scalability on normal -+ hardware and commodity servers. Not recommended for 4096 CPUs. -+ -+ Currently incompatible with the Group CPU scheduler, and RCU TORTURE -+ TEST so these options are disabled. -+ -+ Say Y here. -+ default y -+ -+ - config BROKEN - bool - -@@ -302,7 +316,7 @@ - # Kind of a stub config for the pure tick based cputime accounting - config TICK_CPU_ACCOUNTING - bool "Simple tick based cputime accounting" -- depends on !S390 && !NO_HZ_FULL -+ depends on !S390 && !NO_HZ_FULL && !SCHED_BFS - help - This is the basic tick based cputime accounting that maintains - statistics about user, system and idle time spent on per jiffies -@@ -325,7 +339,7 @@ - - config VIRT_CPU_ACCOUNTING_GEN - bool "Full dynticks CPU time accounting" -- depends on HAVE_CONTEXT_TRACKING && 64BIT -+ depends on HAVE_CONTEXT_TRACKING && 64BIT && !SCHED_BFS - select VIRT_CPU_ACCOUNTING - select CONTEXT_TRACKING - help -@@ -795,6 +809,7 @@ - depends on ARCH_SUPPORTS_NUMA_BALANCING - depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY - depends on SMP && NUMA && MIGRATION -+ depends on !SCHED_BFS - help - This option adds support for automatic NUMA aware memory/task placement. - The mechanism is quite primitive and is based on migrating memory when -@@ -857,6 +872,7 @@ - - config CGROUP_CPUACCT - bool "Simple CPU accounting cgroup subsystem" -+ depends on !SCHED_BFS - help - Provides a simple Resource Controller for monitoring the - total CPU consumed by the tasks in a cgroup. -@@ -959,6 +975,7 @@ - - menuconfig CGROUP_SCHED - bool "Group CPU scheduler" -+ depends on !SCHED_BFS - default n - help - This feature lets CPU scheduler recognize task groups and control CPU -@@ -1123,6 +1140,7 @@ - - config SCHED_AUTOGROUP - bool "Automatic process group scheduling" -+ depends on !SCHED_BFS - select EVENTFD - select CGROUPS - select CGROUP_SCHED -@@ -1526,38 +1544,8 @@ - - On non-ancient distros (post-2000 ones) N is usually a safe choice. - --choice -- prompt "Choose SLAB allocator" -- default SLUB -- help -- This option allows to select a slab allocator. -- --config SLAB -- bool "SLAB" -- help -- The regular slab allocator that is established and known to work -- well in all environments. It organizes cache hot objects in -- per cpu and per node queues. -- - config SLUB -- bool "SLUB (Unqueued Allocator)" -- help -- SLUB is a slab allocator that minimizes cache line usage -- instead of managing queues of cached objects (SLAB approach). -- Per cpu caching is realized using slabs of objects instead -- of queues of objects. SLUB can use memory efficiently -- and has enhanced diagnostics. SLUB is the default choice for -- a slab allocator. -- --config SLOB -- depends on EXPERT -- bool "SLOB (Simple Allocator)" -- help -- SLOB replaces the stock allocator with a drastically simpler -- allocator. SLOB is generally more space efficient but -- does not perform as well on large systems. -- --endchoice -+ def_bool y - - config MMAP_ALLOW_UNINITIALIZED - bool "Allow mmapped anonymous memory to be uninitialized" -Index: linux-3.10-ck1/init/main.c -=================================================================== ---- linux-3.10-ck1.orig/init/main.c 2013-07-09 17:28:57.127502084 +1000 -+++ linux-3.10-ck1/init/main.c 2013-07-09 17:29:00.839501924 +1000 -@@ -700,7 +700,6 @@ - return ret; - } - -- - extern initcall_t __initcall_start[]; - extern initcall_t __initcall0_start[]; - extern initcall_t __initcall1_start[]; -@@ -820,6 +819,8 @@ - - flush_delayed_fput(); - -+ print_scheduler_version(); -+ - if (ramdisk_execute_command) { - if (!run_init_process(ramdisk_execute_command)) - return 0; -Index: linux-3.10-ck1/kernel/delayacct.c -=================================================================== ---- linux-3.10-ck1.orig/kernel/delayacct.c 2013-07-09 17:28:57.202502081 +1000 -+++ linux-3.10-ck1/kernel/delayacct.c 2013-07-09 17:29:00.839501924 +1000 -@@ -133,7 +133,7 @@ - */ - t1 = tsk->sched_info.pcount; - t2 = tsk->sched_info.run_delay; -- t3 = tsk->se.sum_exec_runtime; -+ t3 = tsk_seruntime(tsk); - - d->cpu_count += t1; - -Index: linux-3.10-ck1/kernel/exit.c -=================================================================== ---- linux-3.10-ck1.orig/kernel/exit.c 2013-07-09 17:28:57.186502081 +1000 -+++ linux-3.10-ck1/kernel/exit.c 2013-07-09 17:29:00.839501924 +1000 -@@ -135,7 +135,7 @@ - sig->inblock += task_io_get_inblock(tsk); - sig->oublock += task_io_get_oublock(tsk); - task_io_accounting_add(&sig->ioac, &tsk->ioac); -- sig->sum_sched_runtime += tsk->se.sum_exec_runtime; -+ sig->sum_sched_runtime += tsk_seruntime(tsk); - } - - sig->nr_threads--; -Index: linux-3.10-ck1/kernel/posix-cpu-timers.c -=================================================================== ---- linux-3.10-ck1.orig/kernel/posix-cpu-timers.c 2013-07-09 17:28:57.182502082 +1000 -+++ linux-3.10-ck1/kernel/posix-cpu-timers.c 2013-07-09 17:29:00.840501924 +1000 -@@ -498,11 +498,11 @@ - { - cputime_t utime, stime; - -- add_device_randomness((const void*) &tsk->se.sum_exec_runtime, -+ add_device_randomness((const void*) &tsk_seruntime(tsk), - sizeof(unsigned long long)); - task_cputime(tsk, &utime, &stime); - cleanup_timers(tsk->cpu_timers, -- utime, stime, tsk->se.sum_exec_runtime); -+ utime, stime, tsk_seruntime(tsk)); - - } - void posix_cpu_timers_exit_group(struct task_struct *tsk) -@@ -513,7 +513,7 @@ - task_cputime(tsk, &utime, &stime); - cleanup_timers(tsk->signal->cpu_timers, - utime + sig->utime, stime + sig->stime, -- tsk->se.sum_exec_runtime + sig->sum_sched_runtime); -+ tsk_seruntime(tsk) + sig->sum_sched_runtime); - } - - static void clear_dead_task(struct k_itimer *timer, union cpu_time_count now) -@@ -976,7 +976,7 @@ - struct cpu_timer_list *t = list_first_entry(timers, - struct cpu_timer_list, - entry); -- if (!--maxfire || tsk->se.sum_exec_runtime < t->expires.sched) { -+ if (!--maxfire || tsk_seruntime(tsk) < t->expires.sched) { - tsk->cputime_expires.sched_exp = t->expires.sched; - break; - } -@@ -993,7 +993,7 @@ - ACCESS_ONCE(sig->rlim[RLIMIT_RTTIME].rlim_max); - - if (hard != RLIM_INFINITY && -- tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) { -+ tsk_rttimeout(tsk) > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) { - /* - * At the hard limit, we just die. - * No need to calculate anything else now. -@@ -1001,7 +1001,7 @@ - __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); - return; - } -- if (tsk->rt.timeout > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) { -+ if (tsk_rttimeout(tsk) > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) { - /* - * At the soft limit, send a SIGXCPU every second. - */ -@@ -1282,7 +1282,7 @@ - struct task_cputime task_sample = { - .utime = utime, - .stime = stime, -- .sum_exec_runtime = tsk->se.sum_exec_runtime -+ .sum_exec_runtime = tsk_seruntime(tsk) - }; - - if (task_cputime_expired(&task_sample, &tsk->cputime_expires)) -Index: linux-3.10-ck1/kernel/sysctl.c -=================================================================== ---- linux-3.10-ck1.orig/kernel/sysctl.c 2013-07-09 17:28:57.173502082 +1000 -+++ linux-3.10-ck1/kernel/sysctl.c 2013-07-09 17:29:00.840501924 +1000 -@@ -128,7 +128,12 @@ - static int __maybe_unused two = 2; - static int __maybe_unused three = 3; - static unsigned long one_ul = 1; --static int one_hundred = 100; -+static int __maybe_unused one_hundred = 100; -+#ifdef CONFIG_SCHED_BFS -+extern int rr_interval; -+extern int sched_iso_cpu; -+static int __read_mostly one_thousand = 1000; -+#endif - #ifdef CONFIG_PRINTK - static int ten_thousand = 10000; - #endif -@@ -256,7 +261,7 @@ - { } - }; - --#ifdef CONFIG_SCHED_DEBUG -+#if defined(CONFIG_SCHED_DEBUG) && !defined(CONFIG_SCHED_BFS) - static int min_sched_granularity_ns = 100000; /* 100 usecs */ - static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */ - static int min_wakeup_granularity_ns; /* 0 usecs */ -@@ -273,6 +278,7 @@ - #endif - - static struct ctl_table kern_table[] = { -+#ifndef CONFIG_SCHED_BFS - { - .procname = "sched_child_runs_first", - .data = &sysctl_sched_child_runs_first, -@@ -436,6 +442,7 @@ - .extra1 = &one, - }, - #endif -+#endif /* !CONFIG_SCHED_BFS */ - #ifdef CONFIG_PROVE_LOCKING - { - .procname = "prove_locking", -@@ -907,6 +914,26 @@ - .proc_handler = proc_dointvec, - }, - #endif -+#ifdef CONFIG_SCHED_BFS -+ { -+ .procname = "rr_interval", -+ .data = &rr_interval, -+ .maxlen = sizeof (int), -+ .mode = 0644, -+ .proc_handler = &proc_dointvec_minmax, -+ .extra1 = &one, -+ .extra2 = &one_thousand, -+ }, -+ { -+ .procname = "iso_cpu", -+ .data = &sched_iso_cpu, -+ .maxlen = sizeof (int), -+ .mode = 0644, -+ .proc_handler = &proc_dointvec_minmax, -+ .extra1 = &zero, -+ .extra2 = &one_hundred, -+ }, -+#endif - #if defined(CONFIG_S390) && defined(CONFIG_SMP) - { - .procname = "spin_retry", -Index: linux-3.10-ck1/lib/Kconfig.debug -=================================================================== ---- linux-3.10-ck1.orig/lib/Kconfig.debug 2013-07-09 17:28:57.137502083 +1000 -+++ linux-3.10-ck1/lib/Kconfig.debug 2013-07-09 17:29:00.840501924 +1000 -@@ -940,7 +940,7 @@ - - config RCU_TORTURE_TEST - tristate "torture tests for RCU" -- depends on DEBUG_KERNEL -+ depends on DEBUG_KERNEL && !SCHED_BFS - default n - help - This option provides a kernel module that runs torture tests -Index: linux-3.10-ck1/include/linux/jiffies.h -=================================================================== ---- linux-3.10-ck1.orig/include/linux/jiffies.h 2013-07-09 17:28:57.150502083 +1000 -+++ linux-3.10-ck1/include/linux/jiffies.h 2013-07-09 17:29:00.840501924 +1000 -@@ -159,7 +159,7 @@ - * Have the 32 bit jiffies value wrap 5 minutes after boot - * so jiffies wrap bugs show up earlier. - */ --#define INITIAL_JIFFIES ((unsigned long)(unsigned int) (-300*HZ)) -+#define INITIAL_JIFFIES ((unsigned long)(unsigned int) (-10*HZ)) - - /* - * Change timeval to jiffies, trying to avoid the -Index: linux-3.10-ck1/drivers/cpufreq/cpufreq.c -=================================================================== ---- linux-3.10-ck1.orig/drivers/cpufreq/cpufreq.c 2013-07-09 17:28:57.224502080 +1000 -+++ linux-3.10-ck1/drivers/cpufreq/cpufreq.c 2013-07-09 17:29:00.841501924 +1000 -@@ -30,6 +30,7 @@ - #include - #include - #include -+#include - #include - - #include -@@ -1473,6 +1474,12 @@ - - if (cpufreq_driver->target) - retval = cpufreq_driver->target(policy, target_freq, relation); -+ if (likely(retval != -EINVAL)) { -+ if (target_freq == policy->max) -+ cpu_nonscaling(policy->cpu); -+ else -+ cpu_scaling(policy->cpu); -+ } - - return retval; - } -Index: linux-3.10-ck1/drivers/cpufreq/cpufreq_ondemand.c -=================================================================== ---- linux-3.10-ck1.orig/drivers/cpufreq/cpufreq_ondemand.c 2013-07-09 17:28:57.214502080 +1000 -+++ linux-3.10-ck1/drivers/cpufreq/cpufreq_ondemand.c 2013-07-09 17:29:00.841501924 +1000 -@@ -29,8 +29,8 @@ - #include "cpufreq_governor.h" - - /* On-demand governor macros */ --#define DEF_FREQUENCY_DOWN_DIFFERENTIAL (10) --#define DEF_FREQUENCY_UP_THRESHOLD (80) -+#define DEF_FREQUENCY_DOWN_DIFFERENTIAL (26) -+#define DEF_FREQUENCY_UP_THRESHOLD (63) - #define DEF_SAMPLING_DOWN_FACTOR (1) - #define MAX_SAMPLING_DOWN_FACTOR (100000) - #define MICRO_FREQUENCY_DOWN_DIFFERENTIAL (3) -@@ -160,10 +160,10 @@ - } - - /* -- * Every sampling_rate, we check, if current idle time is less than 20% -+ * Every sampling_rate, we check, if current idle time is less than 37% - * (default), then we try to increase frequency. Every sampling_rate, we look - * for the lowest frequency which can sustain the load while keeping idle time -- * over 30%. If such a frequency exist, we try to decrease to this frequency. -+ * over 63%. If such a frequency exist, we try to decrease to this frequency. - * - * Any frequency increase takes it to the maximum frequency. Frequency reduction - * happens at minimum steps of 5% (default) of current frequency -Index: linux-3.10-ck1/kernel/sched/bfs.c -=================================================================== ---- /dev/null 1970-01-01 00:00:00.000000000 +0000 -+++ linux-3.10-ck1/kernel/sched/bfs.c 2013-07-09 17:29:00.843501924 +1000 -@@ -0,0 +1,7423 @@ -+/* -+ * kernel/sched/bfs.c, was kernel/sched.c -+ * -+ * Kernel scheduler and related syscalls -+ * -+ * Copyright (C) 1991-2002 Linus Torvalds -+ * -+ * 1996-12-23 Modified by Dave Grothe to fix bugs in semaphores and -+ * make semaphores SMP safe -+ * 1998-11-19 Implemented schedule_timeout() and related stuff -+ * by Andrea Arcangeli -+ * 2002-01-04 New ultra-scalable O(1) scheduler by Ingo Molnar: -+ * hybrid priority-list and round-robin design with -+ * an array-switch method of distributing timeslices -+ * and per-CPU runqueues. Cleanups and useful suggestions -+ * by Davide Libenzi, preemptible kernel bits by Robert Love. -+ * 2003-09-03 Interactivity tuning by Con Kolivas. -+ * 2004-04-02 Scheduler domains code by Nick Piggin -+ * 2007-04-15 Work begun on replacing all interactivity tuning with a -+ * fair scheduling design by Con Kolivas. -+ * 2007-05-05 Load balancing (smp-nice) and other improvements -+ * by Peter Williams -+ * 2007-05-06 Interactivity improvements to CFS by Mike Galbraith -+ * 2007-07-01 Group scheduling enhancements by Srivatsa Vaddagiri -+ * 2007-11-29 RT balancing improvements by Steven Rostedt, Gregory Haskins, -+ * Thomas Gleixner, Mike Kravetz -+ * now Brainfuck deadline scheduling policy by Con Kolivas deletes -+ * a whole lot of those previous things. -+ */ -+ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+#include -+#include -+#include -+#include -+#ifdef CONFIG_PARAVIRT -+#include -+#endif -+ -+#include "cpupri.h" -+#include "../workqueue_internal.h" -+#include "../smpboot.h" -+ -+#define CREATE_TRACE_POINTS -+#include -+ -+#define rt_prio(prio) unlikely((prio) < MAX_RT_PRIO) -+#define rt_task(p) rt_prio((p)->prio) -+#define rt_queue(rq) rt_prio((rq)->rq_prio) -+#define batch_task(p) (unlikely((p)->policy == SCHED_BATCH)) -+#define is_rt_policy(policy) ((policy) == SCHED_FIFO || \ -+ (policy) == SCHED_RR) -+#define has_rt_policy(p) unlikely(is_rt_policy((p)->policy)) -+#define idleprio_task(p) unlikely((p)->policy == SCHED_IDLEPRIO) -+#define iso_task(p) unlikely((p)->policy == SCHED_ISO) -+#define iso_queue(rq) unlikely((rq)->rq_policy == SCHED_ISO) -+#define rq_running_iso(rq) ((rq)->rq_prio == ISO_PRIO) -+ -+#define ISO_PERIOD ((5 * HZ * grq.noc) + 1) -+ -+/* -+ * Convert user-nice values [ -20 ... 0 ... 19 ] -+ * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ], -+ * and back. -+ */ -+#define NICE_TO_PRIO(nice) (MAX_RT_PRIO + (nice) + 20) -+#define PRIO_TO_NICE(prio) ((prio) - MAX_RT_PRIO - 20) -+#define TASK_NICE(p) PRIO_TO_NICE((p)->static_prio) -+ -+/* -+ * 'User priority' is the nice value converted to something we -+ * can work with better when scaling various scheduler parameters, -+ * it's a [ 0 ... 39 ] range. -+ */ -+#define USER_PRIO(p) ((p) - MAX_RT_PRIO) -+#define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio) -+#define MAX_USER_PRIO (USER_PRIO(MAX_PRIO)) -+#define SCHED_PRIO(p) ((p) + MAX_RT_PRIO) -+#define STOP_PRIO (MAX_RT_PRIO - 1) -+ -+/* -+ * Some helpers for converting to/from various scales. Use shifts to get -+ * approximate multiples of ten for less overhead. -+ */ -+#define JIFFIES_TO_NS(TIME) ((TIME) * (1000000000 / HZ)) -+#define JIFFY_NS (1000000000 / HZ) -+#define HALF_JIFFY_NS (1000000000 / HZ / 2) -+#define HALF_JIFFY_US (1000000 / HZ / 2) -+#define MS_TO_NS(TIME) ((TIME) << 20) -+#define MS_TO_US(TIME) ((TIME) << 10) -+#define NS_TO_MS(TIME) ((TIME) >> 20) -+#define NS_TO_US(TIME) ((TIME) >> 10) -+ -+#define RESCHED_US (100) /* Reschedule if less than this many μs left */ -+ -+void print_scheduler_version(void) -+{ -+ printk(KERN_INFO "BFS CPU scheduler v0.440 by Con Kolivas.\n"); -+} -+ -+/* -+ * This is the time all tasks within the same priority round robin. -+ * Value is in ms and set to a minimum of 6ms. Scales with number of cpus. -+ * Tunable via /proc interface. -+ */ -+int rr_interval __read_mostly = 6; -+ -+/* -+ * sched_iso_cpu - sysctl which determines the cpu percentage SCHED_ISO tasks -+ * are allowed to run five seconds as real time tasks. This is the total over -+ * all online cpus. -+ */ -+int sched_iso_cpu __read_mostly = 70; -+ -+/* -+ * The relative length of deadline for each priority(nice) level. -+ */ -+static int prio_ratios[PRIO_RANGE] __read_mostly; -+ -+/* -+ * The quota handed out to tasks of all priority levels when refilling their -+ * time_slice. -+ */ -+static inline int timeslice(void) -+{ -+ return MS_TO_US(rr_interval); -+} -+ -+/* -+ * The global runqueue data that all CPUs work off. Data is protected either -+ * by the global grq lock, or the discrete lock that precedes the data in this -+ * struct. -+ */ -+struct global_rq { -+ raw_spinlock_t lock; -+ unsigned long nr_running; -+ unsigned long nr_uninterruptible; -+ unsigned long long nr_switches; -+ struct list_head queue[PRIO_LIMIT]; -+ DECLARE_BITMAP(prio_bitmap, PRIO_LIMIT + 1); -+#ifdef CONFIG_SMP -+ unsigned long qnr; /* queued not running */ -+ cpumask_t cpu_idle_map; -+ bool idle_cpus; -+#endif -+ int noc; /* num_online_cpus stored and updated when it changes */ -+ u64 niffies; /* Nanosecond jiffies */ -+ unsigned long last_jiffy; /* Last jiffy we updated niffies */ -+ -+ raw_spinlock_t iso_lock; -+ int iso_ticks; -+ bool iso_refractory; -+}; -+ -+#ifdef CONFIG_SMP -+ -+/* -+ * We add the notion of a root-domain which will be used to define per-domain -+ * variables. Each exclusive cpuset essentially defines an island domain by -+ * fully partitioning the member cpus from any other cpuset. Whenever a new -+ * exclusive cpuset is created, we also create and attach a new root-domain -+ * object. -+ * -+ */ -+struct root_domain { -+ atomic_t refcount; -+ atomic_t rto_count; -+ struct rcu_head rcu; -+ cpumask_var_t span; -+ cpumask_var_t online; -+ -+ /* -+ * The "RT overload" flag: it gets set if a CPU has more than -+ * one runnable RT task. -+ */ -+ cpumask_var_t rto_mask; -+ struct cpupri cpupri; -+}; -+ -+/* -+ * By default the system creates a single root-domain with all cpus as -+ * members (mimicking the global state we have today). -+ */ -+static struct root_domain def_root_domain; -+ -+#endif /* CONFIG_SMP */ -+ -+/* There can be only one */ -+static struct global_rq grq; -+ -+/* -+ * This is the main, per-CPU runqueue data structure. -+ * This data should only be modified by the local cpu. -+ */ -+struct rq { -+ struct task_struct *curr, *idle, *stop; -+ struct mm_struct *prev_mm; -+ -+ /* Stored data about rq->curr to work outside grq lock */ -+ u64 rq_deadline; -+ unsigned int rq_policy; -+ int rq_time_slice; -+ u64 rq_last_ran; -+ int rq_prio; -+ bool rq_running; /* There is a task running */ -+ -+ /* Accurate timekeeping data */ -+ u64 timekeep_clock; -+ unsigned long user_pc, nice_pc, irq_pc, softirq_pc, system_pc, -+ iowait_pc, idle_pc; -+ atomic_t nr_iowait; -+ -+#ifdef CONFIG_SMP -+ int cpu; /* cpu of this runqueue */ -+ bool online; -+ bool scaling; /* This CPU is managed by a scaling CPU freq governor */ -+ struct task_struct *sticky_task; -+ -+ struct root_domain *rd; -+ struct sched_domain *sd; -+ int *cpu_locality; /* CPU relative cache distance */ -+#ifdef CONFIG_SCHED_SMT -+ bool (*siblings_idle)(int cpu); -+ /* See if all smt siblings are idle */ -+ cpumask_t smt_siblings; -+#endif /* CONFIG_SCHED_SMT */ -+#ifdef CONFIG_SCHED_MC -+ bool (*cache_idle)(int cpu); -+ /* See if all cache siblings are idle */ -+ cpumask_t cache_siblings; -+#endif /* CONFIG_SCHED_MC */ -+ u64 last_niffy; /* Last time this RQ updated grq.niffies */ -+#endif /* CONFIG_SMP */ -+#ifdef CONFIG_IRQ_TIME_ACCOUNTING -+ u64 prev_irq_time; -+#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ -+#ifdef CONFIG_PARAVIRT -+ u64 prev_steal_time; -+#endif /* CONFIG_PARAVIRT */ -+#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING -+ u64 prev_steal_time_rq; -+#endif /* CONFIG_PARAVIRT_TIME_ACCOUNTING */ -+ -+ u64 clock, old_clock, last_tick; -+ u64 clock_task; -+ bool dither; -+ -+#ifdef CONFIG_SCHEDSTATS -+ -+ /* latency stats */ -+ struct sched_info rq_sched_info; -+ unsigned long long rq_cpu_time; -+ /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ -+ -+ /* sys_sched_yield() stats */ -+ unsigned int yld_count; -+ -+ /* schedule() stats */ -+ unsigned int sched_switch; -+ unsigned int sched_count; -+ unsigned int sched_goidle; -+ -+ /* try_to_wake_up() stats */ -+ unsigned int ttwu_count; -+ unsigned int ttwu_local; -+#endif /* CONFIG_SCHEDSTATS */ -+}; -+ -+DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); -+static DEFINE_MUTEX(sched_hotcpu_mutex); -+ -+#ifdef CONFIG_SMP -+#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) -+#define this_rq() (&__get_cpu_var(runqueues)) -+#define task_rq(p) cpu_rq(task_cpu(p)) -+#define cpu_curr(cpu) (cpu_rq(cpu)->curr) -+/* -+ * sched_domains_mutex serialises calls to init_sched_domains, -+ * detach_destroy_domains and partition_sched_domains. -+ */ -+static DEFINE_MUTEX(sched_domains_mutex); -+ -+/* -+ * By default the system creates a single root-domain with all cpus as -+ * members (mimicking the global state we have today). -+ */ -+static struct root_domain def_root_domain; -+ -+int __weak arch_sd_sibling_asym_packing(void) -+{ -+ return 0*SD_ASYM_PACKING; -+} -+#endif /* CONFIG_SMP */ -+ -+#define rcu_dereference_check_sched_domain(p) \ -+ rcu_dereference_check((p), \ -+ lockdep_is_held(&sched_domains_mutex)) -+ -+/* -+ * The domain tree (rq->sd) is protected by RCU's quiescent state transition. -+ * See detach_destroy_domains: synchronize_sched for details. -+ * -+ * The domain tree of any CPU may only be accessed from within -+ * preempt-disabled sections. -+ */ -+#define for_each_domain(cpu, __sd) \ -+ for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); __sd; __sd = __sd->parent) -+ -+static inline void update_rq_clock(struct rq *rq); -+ -+/* -+ * Sanity check should sched_clock return bogus values. We make sure it does -+ * not appear to go backwards, and use jiffies to determine the maximum and -+ * minimum it could possibly have increased, and round down to the nearest -+ * jiffy when it falls outside this. -+ */ -+static inline void niffy_diff(s64 *niff_diff, int jiff_diff) -+{ -+ unsigned long min_diff, max_diff; -+ -+ if (jiff_diff > 1) -+ min_diff = JIFFIES_TO_NS(jiff_diff - 1); -+ else -+ min_diff = 1; -+ /* Round up to the nearest tick for maximum */ -+ max_diff = JIFFIES_TO_NS(jiff_diff + 1); -+ -+ if (unlikely(*niff_diff < min_diff || *niff_diff > max_diff)) -+ *niff_diff = min_diff; -+} -+ -+#ifdef CONFIG_SMP -+static inline int cpu_of(struct rq *rq) -+{ -+ return rq->cpu; -+} -+ -+/* -+ * Niffies are a globally increasing nanosecond counter. Whenever a runqueue -+ * clock is updated with the grq.lock held, it is an opportunity to update the -+ * niffies value. Any CPU can update it by adding how much its clock has -+ * increased since it last updated niffies, minus any added niffies by other -+ * CPUs. -+ */ -+static inline void update_clocks(struct rq *rq) -+{ -+ s64 ndiff; -+ long jdiff; -+ -+ update_rq_clock(rq); -+ ndiff = rq->clock - rq->old_clock; -+ /* old_clock is only updated when we are updating niffies */ -+ rq->old_clock = rq->clock; -+ ndiff -= grq.niffies - rq->last_niffy; -+ jdiff = jiffies - grq.last_jiffy; -+ niffy_diff(&ndiff, jdiff); -+ grq.last_jiffy += jdiff; -+ grq.niffies += ndiff; -+ rq->last_niffy = grq.niffies; -+} -+#else /* CONFIG_SMP */ -+static struct rq *uprq; -+#define cpu_rq(cpu) (uprq) -+#define this_rq() (uprq) -+#define task_rq(p) (uprq) -+#define cpu_curr(cpu) ((uprq)->curr) -+static inline int cpu_of(struct rq *rq) -+{ -+ return 0; -+} -+ -+static inline void update_clocks(struct rq *rq) -+{ -+ s64 ndiff; -+ long jdiff; -+ -+ update_rq_clock(rq); -+ ndiff = rq->clock - rq->old_clock; -+ rq->old_clock = rq->clock; -+ jdiff = jiffies - grq.last_jiffy; -+ niffy_diff(&ndiff, jdiff); -+ grq.last_jiffy += jdiff; -+ grq.niffies += ndiff; -+} -+#endif -+#define raw_rq() (&__raw_get_cpu_var(runqueues)) -+ -+#include "stats.h" -+ -+#ifndef prepare_arch_switch -+# define prepare_arch_switch(next) do { } while (0) -+#endif -+#ifndef finish_arch_switch -+# define finish_arch_switch(prev) do { } while (0) -+#endif -+#ifndef finish_arch_post_lock_switch -+# define finish_arch_post_lock_switch() do { } while (0) -+#endif -+ -+/* -+ * All common locking functions performed on grq.lock. rq->clock is local to -+ * the CPU accessing it so it can be modified just with interrupts disabled -+ * when we're not updating niffies. -+ * Looking up task_rq must be done under grq.lock to be safe. -+ */ -+static void update_rq_clock_task(struct rq *rq, s64 delta); -+ -+static inline void update_rq_clock(struct rq *rq) -+{ -+ s64 delta = sched_clock_cpu(cpu_of(rq)) - rq->clock; -+ -+ rq->clock += delta; -+ update_rq_clock_task(rq, delta); -+} -+ -+static inline bool task_running(struct task_struct *p) -+{ -+ return p->on_cpu; -+} -+ -+static inline void grq_lock(void) -+ __acquires(grq.lock) -+{ -+ raw_spin_lock(&grq.lock); -+} -+ -+static inline void grq_unlock(void) -+ __releases(grq.lock) -+{ -+ raw_spin_unlock(&grq.lock); -+} -+ -+static inline void grq_lock_irq(void) -+ __acquires(grq.lock) -+{ -+ raw_spin_lock_irq(&grq.lock); -+} -+ -+static inline void time_lock_grq(struct rq *rq) -+ __acquires(grq.lock) -+{ -+ grq_lock(); -+ update_clocks(rq); -+} -+ -+static inline void grq_unlock_irq(void) -+ __releases(grq.lock) -+{ -+ raw_spin_unlock_irq(&grq.lock); -+} -+ -+static inline void grq_lock_irqsave(unsigned long *flags) -+ __acquires(grq.lock) -+{ -+ raw_spin_lock_irqsave(&grq.lock, *flags); -+} -+ -+static inline void grq_unlock_irqrestore(unsigned long *flags) -+ __releases(grq.lock) -+{ -+ raw_spin_unlock_irqrestore(&grq.lock, *flags); -+} -+ -+static inline struct rq -+*task_grq_lock(struct task_struct *p, unsigned long *flags) -+ __acquires(grq.lock) -+{ -+ grq_lock_irqsave(flags); -+ return task_rq(p); -+} -+ -+static inline struct rq -+*time_task_grq_lock(struct task_struct *p, unsigned long *flags) -+ __acquires(grq.lock) -+{ -+ struct rq *rq = task_grq_lock(p, flags); -+ update_clocks(rq); -+ return rq; -+} -+ -+static inline struct rq *task_grq_lock_irq(struct task_struct *p) -+ __acquires(grq.lock) -+{ -+ grq_lock_irq(); -+ return task_rq(p); -+} -+ -+static inline void time_task_grq_lock_irq(struct task_struct *p) -+ __acquires(grq.lock) -+{ -+ struct rq *rq = task_grq_lock_irq(p); -+ update_clocks(rq); -+} -+ -+static inline void task_grq_unlock_irq(void) -+ __releases(grq.lock) -+{ -+ grq_unlock_irq(); -+} -+ -+static inline void task_grq_unlock(unsigned long *flags) -+ __releases(grq.lock) -+{ -+ grq_unlock_irqrestore(flags); -+} -+ -+/** -+ * grunqueue_is_locked -+ * -+ * Returns true if the global runqueue is locked. -+ * This interface allows printk to be called with the runqueue lock -+ * held and know whether or not it is OK to wake up the klogd. -+ */ -+bool grunqueue_is_locked(void) -+{ -+ return raw_spin_is_locked(&grq.lock); -+} -+ -+void grq_unlock_wait(void) -+ __releases(grq.lock) -+{ -+ smp_mb(); /* spin-unlock-wait is not a full memory barrier */ -+ raw_spin_unlock_wait(&grq.lock); -+} -+ -+static inline void time_grq_lock(struct rq *rq, unsigned long *flags) -+ __acquires(grq.lock) -+{ -+ local_irq_save(*flags); -+ time_lock_grq(rq); -+} -+ -+static inline struct rq *__task_grq_lock(struct task_struct *p) -+ __acquires(grq.lock) -+{ -+ grq_lock(); -+ return task_rq(p); -+} -+ -+static inline void __task_grq_unlock(void) -+ __releases(grq.lock) -+{ -+ grq_unlock(); -+} -+ -+/* -+ * Look for any tasks *anywhere* that are running nice 0 or better. We do -+ * this lockless for overhead reasons since the occasional wrong result -+ * is harmless. -+ */ -+bool above_background_load(void) -+{ -+ int cpu; -+ -+ for_each_online_cpu(cpu) { -+ struct task_struct *cpu_curr = cpu_rq(cpu)->curr; -+ -+ if (unlikely(!cpu_curr)) -+ continue; -+ if (PRIO_TO_NICE(cpu_curr->static_prio) < 1) { -+ return true; -+ } -+ } -+ return false; -+} -+ -+#ifndef __ARCH_WANT_UNLOCKED_CTXSW -+static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) -+{ -+} -+ -+static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) -+{ -+#ifdef CONFIG_DEBUG_SPINLOCK -+ /* this is a valid case when another task releases the spinlock */ -+ grq.lock.owner = current; -+#endif -+ /* -+ * If we are tracking spinlock dependencies then we have to -+ * fix up the runqueue lock - which gets 'carried over' from -+ * prev into current: -+ */ -+ spin_acquire(&grq.lock.dep_map, 0, 0, _THIS_IP_); -+ -+ grq_unlock_irq(); -+} -+ -+#else /* __ARCH_WANT_UNLOCKED_CTXSW */ -+ -+static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) -+{ -+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW -+ grq_unlock_irq(); -+#else -+ grq_unlock(); -+#endif -+} -+ -+static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) -+{ -+ smp_wmb(); -+#ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW -+ local_irq_enable(); -+#endif -+} -+#endif /* __ARCH_WANT_UNLOCKED_CTXSW */ -+ -+static inline bool deadline_before(u64 deadline, u64 time) -+{ -+ return (deadline < time); -+} -+ -+static inline bool deadline_after(u64 deadline, u64 time) -+{ -+ return (deadline > time); -+} -+ -+/* -+ * A task that is queued but not running will be on the grq run list. -+ * A task that is not running or queued will not be on the grq run list. -+ * A task that is currently running will have ->on_cpu set but not on the -+ * grq run list. -+ */ -+static inline bool task_queued(struct task_struct *p) -+{ -+ return (!list_empty(&p->run_list)); -+} -+ -+/* -+ * Removing from the global runqueue. Enter with grq locked. -+ */ -+static void dequeue_task(struct task_struct *p) -+{ -+ list_del_init(&p->run_list); -+ if (list_empty(grq.queue + p->prio)) -+ __clear_bit(p->prio, grq.prio_bitmap); -+} -+ -+/* -+ * To determine if it's safe for a task of SCHED_IDLEPRIO to actually run as -+ * an idle task, we ensure none of the following conditions are met. -+ */ -+static bool idleprio_suitable(struct task_struct *p) -+{ -+ return (!freezing(p) && !signal_pending(p) && -+ !(task_contributes_to_load(p)) && !(p->flags & (PF_EXITING))); -+} -+ -+/* -+ * To determine if a task of SCHED_ISO can run in pseudo-realtime, we check -+ * that the iso_refractory flag is not set. -+ */ -+static bool isoprio_suitable(void) -+{ -+ return !grq.iso_refractory; -+} -+ -+/* -+ * Adding to the global runqueue. Enter with grq locked. -+ */ -+static void enqueue_task(struct task_struct *p) -+{ -+ if (!rt_task(p)) { -+ /* Check it hasn't gotten rt from PI */ -+ if ((idleprio_task(p) && idleprio_suitable(p)) || -+ (iso_task(p) && isoprio_suitable())) -+ p->prio = p->normal_prio; -+ else -+ p->prio = NORMAL_PRIO; -+ } -+ __set_bit(p->prio, grq.prio_bitmap); -+ list_add_tail(&p->run_list, grq.queue + p->prio); -+ sched_info_queued(p); -+} -+ -+/* Only idle task does this as a real time task*/ -+static inline void enqueue_task_head(struct task_struct *p) -+{ -+ __set_bit(p->prio, grq.prio_bitmap); -+ list_add(&p->run_list, grq.queue + p->prio); -+ sched_info_queued(p); -+} -+ -+static inline void requeue_task(struct task_struct *p) -+{ -+ sched_info_queued(p); -+} -+ -+/* -+ * Returns the relative length of deadline all compared to the shortest -+ * deadline which is that of nice -20. -+ */ -+static inline int task_prio_ratio(struct task_struct *p) -+{ -+ return prio_ratios[TASK_USER_PRIO(p)]; -+} -+ -+/* -+ * task_timeslice - all tasks of all priorities get the exact same timeslice -+ * length. CPU distribution is handled by giving different deadlines to -+ * tasks of different priorities. Use 128 as the base value for fast shifts. -+ */ -+static inline int task_timeslice(struct task_struct *p) -+{ -+ return (rr_interval * task_prio_ratio(p) / 128); -+} -+ -+#ifdef CONFIG_SMP -+/* -+ * qnr is the "queued but not running" count which is the total number of -+ * tasks on the global runqueue list waiting for cpu time but not actually -+ * currently running on a cpu. -+ */ -+static inline void inc_qnr(void) -+{ -+ grq.qnr++; -+} -+ -+static inline void dec_qnr(void) -+{ -+ grq.qnr--; -+} -+ -+static inline int queued_notrunning(void) -+{ -+ return grq.qnr; -+} -+ -+/* -+ * The cpu_idle_map stores a bitmap of all the CPUs currently idle to -+ * allow easy lookup of whether any suitable idle CPUs are available. -+ * It's cheaper to maintain a binary yes/no if there are any idle CPUs on the -+ * idle_cpus variable than to do a full bitmask check when we are busy. -+ */ -+static inline void set_cpuidle_map(int cpu) -+{ -+ if (likely(cpu_online(cpu))) { -+ cpu_set(cpu, grq.cpu_idle_map); -+ grq.idle_cpus = true; -+ } -+} -+ -+static inline void clear_cpuidle_map(int cpu) -+{ -+ cpu_clear(cpu, grq.cpu_idle_map); -+ if (cpus_empty(grq.cpu_idle_map)) -+ grq.idle_cpus = false; -+} -+ -+static bool suitable_idle_cpus(struct task_struct *p) -+{ -+ if (!grq.idle_cpus) -+ return false; -+ return (cpus_intersects(p->cpus_allowed, grq.cpu_idle_map)); -+} -+ -+#define CPUIDLE_DIFF_THREAD (1) -+#define CPUIDLE_DIFF_CORE (2) -+#define CPUIDLE_CACHE_BUSY (4) -+#define CPUIDLE_DIFF_CPU (8) -+#define CPUIDLE_THREAD_BUSY (16) -+#define CPUIDLE_DIFF_NODE (32) -+ -+static void resched_task(struct task_struct *p); -+ -+/* -+ * The best idle CPU is chosen according to the CPUIDLE ranking above where the -+ * lowest value would give the most suitable CPU to schedule p onto next. The -+ * order works out to be the following: -+ * -+ * Same core, idle or busy cache, idle or busy threads -+ * Other core, same cache, idle or busy cache, idle threads. -+ * Same node, other CPU, idle cache, idle threads. -+ * Same node, other CPU, busy cache, idle threads. -+ * Other core, same cache, busy threads. -+ * Same node, other CPU, busy threads. -+ * Other node, other CPU, idle cache, idle threads. -+ * Other node, other CPU, busy cache, idle threads. -+ * Other node, other CPU, busy threads. -+ */ -+static void -+resched_best_mask(int best_cpu, struct rq *rq, cpumask_t *tmpmask) -+{ -+ unsigned int best_ranking = CPUIDLE_DIFF_NODE | CPUIDLE_THREAD_BUSY | -+ CPUIDLE_DIFF_CPU | CPUIDLE_CACHE_BUSY | CPUIDLE_DIFF_CORE | -+ CPUIDLE_DIFF_THREAD; -+ int cpu_tmp; -+ -+ if (cpu_isset(best_cpu, *tmpmask)) -+ goto out; -+ -+ for_each_cpu_mask(cpu_tmp, *tmpmask) { -+ unsigned int ranking; -+ struct rq *tmp_rq; -+ -+ ranking = 0; -+ tmp_rq = cpu_rq(cpu_tmp); -+ -+#ifdef CONFIG_NUMA -+ if (rq->cpu_locality[cpu_tmp] > 3) -+ ranking |= CPUIDLE_DIFF_NODE; -+ else -+#endif -+ if (rq->cpu_locality[cpu_tmp] > 2) -+ ranking |= CPUIDLE_DIFF_CPU; -+#ifdef CONFIG_SCHED_MC -+ if (rq->cpu_locality[cpu_tmp] == 2) -+ ranking |= CPUIDLE_DIFF_CORE; -+ if (!(tmp_rq->cache_idle(cpu_tmp))) -+ ranking |= CPUIDLE_CACHE_BUSY; -+#endif -+#ifdef CONFIG_SCHED_SMT -+ if (rq->cpu_locality[cpu_tmp] == 1) -+ ranking |= CPUIDLE_DIFF_THREAD; -+ if (!(tmp_rq->siblings_idle(cpu_tmp))) -+ ranking |= CPUIDLE_THREAD_BUSY; -+#endif -+ if (ranking < best_ranking) { -+ best_cpu = cpu_tmp; -+ best_ranking = ranking; -+ } -+ } -+out: -+ resched_task(cpu_rq(best_cpu)->curr); -+} -+ -+bool cpus_share_cache(int this_cpu, int that_cpu) -+{ -+ struct rq *this_rq = cpu_rq(this_cpu); -+ -+ return (this_rq->cpu_locality[that_cpu] < 3); -+} -+ -+static void resched_best_idle(struct task_struct *p) -+{ -+ cpumask_t tmpmask; -+ -+ cpus_and(tmpmask, p->cpus_allowed, grq.cpu_idle_map); -+ resched_best_mask(task_cpu(p), task_rq(p), &tmpmask); -+} -+ -+static inline void resched_suitable_idle(struct task_struct *p) -+{ -+ if (suitable_idle_cpus(p)) -+ resched_best_idle(p); -+} -+/* -+ * Flags to tell us whether this CPU is running a CPU frequency governor that -+ * has slowed its speed or not. No locking required as the very rare wrongly -+ * read value would be harmless. -+ */ -+void cpu_scaling(int cpu) -+{ -+ cpu_rq(cpu)->scaling = true; -+} -+ -+void cpu_nonscaling(int cpu) -+{ -+ cpu_rq(cpu)->scaling = false; -+} -+ -+static inline bool scaling_rq(struct rq *rq) -+{ -+ return rq->scaling; -+} -+ -+static inline int locality_diff(struct task_struct *p, struct rq *rq) -+{ -+ return rq->cpu_locality[task_cpu(p)]; -+} -+#else /* CONFIG_SMP */ -+static inline void inc_qnr(void) -+{ -+} -+ -+static inline void dec_qnr(void) -+{ -+} -+ -+static inline int queued_notrunning(void) -+{ -+ return grq.nr_running; -+} -+ -+static inline void set_cpuidle_map(int cpu) -+{ -+} -+ -+static inline void clear_cpuidle_map(int cpu) -+{ -+} -+ -+static inline bool suitable_idle_cpus(struct task_struct *p) -+{ -+ return uprq->curr == uprq->idle; -+} -+ -+static inline void resched_suitable_idle(struct task_struct *p) -+{ -+} -+ -+void cpu_scaling(int __unused) -+{ -+} -+ -+void cpu_nonscaling(int __unused) -+{ -+} -+ -+/* -+ * Although CPUs can scale in UP, there is nowhere else for tasks to go so this -+ * always returns 0. -+ */ -+static inline bool scaling_rq(struct rq *rq) -+{ -+ return false; -+} -+ -+static inline int locality_diff(struct task_struct *p, struct rq *rq) -+{ -+ return 0; -+} -+#endif /* CONFIG_SMP */ -+EXPORT_SYMBOL_GPL(cpu_scaling); -+EXPORT_SYMBOL_GPL(cpu_nonscaling); -+ -+/* -+ * activate_idle_task - move idle task to the _front_ of runqueue. -+ */ -+static inline void activate_idle_task(struct task_struct *p) -+{ -+ enqueue_task_head(p); -+ grq.nr_running++; -+ inc_qnr(); -+} -+ -+static inline int normal_prio(struct task_struct *p) -+{ -+ if (has_rt_policy(p)) -+ return MAX_RT_PRIO - 1 - p->rt_priority; -+ if (idleprio_task(p)) -+ return IDLE_PRIO; -+ if (iso_task(p)) -+ return ISO_PRIO; -+ return NORMAL_PRIO; -+} -+ -+/* -+ * Calculate the current priority, i.e. the priority -+ * taken into account by the scheduler. This value might -+ * be boosted by RT tasks as it will be RT if the task got -+ * RT-boosted. If not then it returns p->normal_prio. -+ */ -+static int effective_prio(struct task_struct *p) -+{ -+ p->normal_prio = normal_prio(p); -+ /* -+ * If we are RT tasks or we were boosted to RT priority, -+ * keep the priority unchanged. Otherwise, update priority -+ * to the normal priority: -+ */ -+ if (!rt_prio(p->prio)) -+ return p->normal_prio; -+ return p->prio; -+} -+ -+/* -+ * activate_task - move a task to the runqueue. Enter with grq locked. -+ */ -+static void activate_task(struct task_struct *p, struct rq *rq) -+{ -+ update_clocks(rq); -+ -+ /* -+ * Sleep time is in units of nanosecs, so shift by 20 to get a -+ * milliseconds-range estimation of the amount of time that the task -+ * spent sleeping: -+ */ -+ if (unlikely(prof_on == SLEEP_PROFILING)) { -+ if (p->state == TASK_UNINTERRUPTIBLE) -+ profile_hits(SLEEP_PROFILING, (void *)get_wchan(p), -+ (rq->clock_task - p->last_ran) >> 20); -+ } -+ -+ p->prio = effective_prio(p); -+ if (task_contributes_to_load(p)) -+ grq.nr_uninterruptible--; -+ enqueue_task(p); -+ grq.nr_running++; -+ inc_qnr(); -+} -+ -+static inline void clear_sticky(struct task_struct *p); -+ -+/* -+ * deactivate_task - If it's running, it's not on the grq and we can just -+ * decrement the nr_running. Enter with grq locked. -+ */ -+static inline void deactivate_task(struct task_struct *p) -+{ -+ if (task_contributes_to_load(p)) -+ grq.nr_uninterruptible++; -+ grq.nr_running--; -+ clear_sticky(p); -+} -+ -+static ATOMIC_NOTIFIER_HEAD(task_migration_notifier); -+ -+void register_task_migration_notifier(struct notifier_block *n) -+{ -+ atomic_notifier_chain_register(&task_migration_notifier, n); -+} -+ -+#ifdef CONFIG_SMP -+void set_task_cpu(struct task_struct *p, unsigned int cpu) -+{ -+#ifdef CONFIG_LOCKDEP -+ /* -+ * The caller should hold grq lock. -+ */ -+ WARN_ON_ONCE(debug_locks && !lockdep_is_held(&grq.lock)); -+#endif -+ trace_sched_migrate_task(p, cpu); -+ if (task_cpu(p) != cpu) -+ perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, NULL, 0); -+ -+ /* -+ * After ->cpu is set up to a new value, task_grq_lock(p, ...) can be -+ * successfully executed on another CPU. We must ensure that updates of -+ * per-task data have been completed by this moment. -+ */ -+ smp_wmb(); -+ task_thread_info(p)->cpu = cpu; -+} -+ -+static inline void clear_sticky(struct task_struct *p) -+{ -+ p->sticky = false; -+} -+ -+static inline bool task_sticky(struct task_struct *p) -+{ -+ return p->sticky; -+} -+ -+/* Reschedule the best idle CPU that is not this one. */ -+static void -+resched_closest_idle(struct rq *rq, int cpu, struct task_struct *p) -+{ -+ cpumask_t tmpmask; -+ -+ cpus_and(tmpmask, p->cpus_allowed, grq.cpu_idle_map); -+ cpu_clear(cpu, tmpmask); -+ if (cpus_empty(tmpmask)) -+ return; -+ resched_best_mask(cpu, rq, &tmpmask); -+} -+ -+/* -+ * We set the sticky flag on a task that is descheduled involuntarily meaning -+ * it is awaiting further CPU time. If the last sticky task is still sticky -+ * but unlucky enough to not be the next task scheduled, we unstick it and try -+ * to find it an idle CPU. Realtime tasks do not stick to minimise their -+ * latency at all times. -+ */ -+static inline void -+swap_sticky(struct rq *rq, int cpu, struct task_struct *p) -+{ -+ if (rq->sticky_task) { -+ if (rq->sticky_task == p) { -+ p->sticky = true; -+ return; -+ } -+ if (task_sticky(rq->sticky_task)) { -+ clear_sticky(rq->sticky_task); -+ resched_closest_idle(rq, cpu, rq->sticky_task); -+ } -+ } -+ if (!rt_task(p)) { -+ p->sticky = true; -+ rq->sticky_task = p; -+ } else { -+ resched_closest_idle(rq, cpu, p); -+ rq->sticky_task = NULL; -+ } -+} -+ -+static inline void unstick_task(struct rq *rq, struct task_struct *p) -+{ -+ rq->sticky_task = NULL; -+ clear_sticky(p); -+} -+#else -+static inline void clear_sticky(struct task_struct *p) -+{ -+} -+ -+static inline bool task_sticky(struct task_struct *p) -+{ -+ return false; -+} -+ -+static inline void -+swap_sticky(struct rq *rq, int cpu, struct task_struct *p) -+{ -+} -+ -+static inline void unstick_task(struct rq *rq, struct task_struct *p) -+{ -+} -+#endif -+ -+/* -+ * Move a task off the global queue and take it to a cpu for it will -+ * become the running task. -+ */ -+static inline void take_task(int cpu, struct task_struct *p) -+{ -+ set_task_cpu(p, cpu); -+ dequeue_task(p); -+ clear_sticky(p); -+ dec_qnr(); -+} -+ -+/* -+ * Returns a descheduling task to the grq runqueue unless it is being -+ * deactivated. -+ */ -+static inline void return_task(struct task_struct *p, bool deactivate) -+{ -+ if (deactivate) -+ deactivate_task(p); -+ else { -+ inc_qnr(); -+ enqueue_task(p); -+ } -+} -+ -+/* -+ * resched_task - mark a task 'to be rescheduled now'. -+ * -+ * On UP this means the setting of the need_resched flag, on SMP it -+ * might also involve a cross-CPU call to trigger the scheduler on -+ * the target CPU. -+ */ -+#ifdef CONFIG_SMP -+ -+#ifndef tsk_is_polling -+#define tsk_is_polling(t) 0 -+#endif -+ -+static void resched_task(struct task_struct *p) -+{ -+ int cpu; -+ -+ assert_raw_spin_locked(&grq.lock); -+ -+ if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED))) -+ return; -+ -+ set_tsk_thread_flag(p, TIF_NEED_RESCHED); -+ -+ cpu = task_cpu(p); -+ if (cpu == smp_processor_id()) -+ return; -+ -+ /* NEED_RESCHED must be visible before we test polling */ -+ smp_mb(); -+ if (!tsk_is_polling(p)) -+ smp_send_reschedule(cpu); -+} -+ -+#else -+static inline void resched_task(struct task_struct *p) -+{ -+ assert_raw_spin_locked(&grq.lock); -+ set_tsk_need_resched(p); -+} -+#endif -+ -+/** -+ * task_curr - is this task currently executing on a CPU? -+ * @p: the task in question. -+ */ -+inline int task_curr(const struct task_struct *p) -+{ -+ return cpu_curr(task_cpu(p)) == p; -+} -+ -+#ifdef CONFIG_SMP -+struct migration_req { -+ struct task_struct *task; -+ int dest_cpu; -+}; -+ -+/* -+ * wait_task_inactive - wait for a thread to unschedule. -+ * -+ * If @match_state is nonzero, it's the @p->state value just checked and -+ * not expected to change. If it changes, i.e. @p might have woken up, -+ * then return zero. When we succeed in waiting for @p to be off its CPU, -+ * we return a positive number (its total switch count). If a second call -+ * a short while later returns the same number, the caller can be sure that -+ * @p has remained unscheduled the whole time. -+ * -+ * The caller must ensure that the task *will* unschedule sometime soon, -+ * else this function might spin for a *long* time. This function can't -+ * be called with interrupts off, or it may introduce deadlock with -+ * smp_call_function() if an IPI is sent by the same process we are -+ * waiting to become inactive. -+ */ -+unsigned long wait_task_inactive(struct task_struct *p, long match_state) -+{ -+ unsigned long flags; -+ bool running, on_rq; -+ unsigned long ncsw; -+ struct rq *rq; -+ -+ for (;;) { -+ /* -+ * We do the initial early heuristics without holding -+ * any task-queue locks at all. We'll only try to get -+ * the runqueue lock when things look like they will -+ * work out! In the unlikely event rq is dereferenced -+ * since we're lockless, grab it again. -+ */ -+#ifdef CONFIG_SMP -+retry_rq: -+ rq = task_rq(p); -+ if (unlikely(!rq)) -+ goto retry_rq; -+#else /* CONFIG_SMP */ -+ rq = task_rq(p); -+#endif -+ /* -+ * If the task is actively running on another CPU -+ * still, just relax and busy-wait without holding -+ * any locks. -+ * -+ * NOTE! Since we don't hold any locks, it's not -+ * even sure that "rq" stays as the right runqueue! -+ * But we don't care, since this will return false -+ * if the runqueue has changed and p is actually now -+ * running somewhere else! -+ */ -+ while (task_running(p) && p == rq->curr) { -+ if (match_state && unlikely(p->state != match_state)) -+ return 0; -+ cpu_relax(); -+ } -+ -+ /* -+ * Ok, time to look more closely! We need the grq -+ * lock now, to be *sure*. If we're wrong, we'll -+ * just go back and repeat. -+ */ -+ rq = task_grq_lock(p, &flags); -+ trace_sched_wait_task(p); -+ running = task_running(p); -+ on_rq = task_queued(p); -+ ncsw = 0; -+ if (!match_state || p->state == match_state) -+ ncsw = p->nvcsw | LONG_MIN; /* sets MSB */ -+ task_grq_unlock(&flags); -+ -+ /* -+ * If it changed from the expected state, bail out now. -+ */ -+ if (unlikely(!ncsw)) -+ break; -+ -+ /* -+ * Was it really running after all now that we -+ * checked with the proper locks actually held? -+ * -+ * Oops. Go back and try again.. -+ */ -+ if (unlikely(running)) { -+ cpu_relax(); -+ continue; -+ } -+ -+ /* -+ * It's not enough that it's not actively running, -+ * it must be off the runqueue _entirely_, and not -+ * preempted! -+ * -+ * So if it was still runnable (but just not actively -+ * running right now), it's preempted, and we should -+ * yield - it could be a while. -+ */ -+ if (unlikely(on_rq)) { -+ ktime_t to = ktime_set(0, NSEC_PER_SEC / HZ); -+ -+ set_current_state(TASK_UNINTERRUPTIBLE); -+ schedule_hrtimeout(&to, HRTIMER_MODE_REL); -+ continue; -+ } -+ -+ /* -+ * Ahh, all good. It wasn't running, and it wasn't -+ * runnable, which means that it will never become -+ * running in the future either. We're all done! -+ */ -+ break; -+ } -+ -+ return ncsw; -+} -+ -+/*** -+ * kick_process - kick a running thread to enter/exit the kernel -+ * @p: the to-be-kicked thread -+ * -+ * Cause a process which is running on another CPU to enter -+ * kernel-mode, without any delay. (to get signals handled.) -+ * -+ * NOTE: this function doesn't have to take the runqueue lock, -+ * because all it wants to ensure is that the remote task enters -+ * the kernel. If the IPI races and the task has been migrated -+ * to another CPU then no harm is done and the purpose has been -+ * achieved as well. -+ */ -+void kick_process(struct task_struct *p) -+{ -+ int cpu; -+ -+ preempt_disable(); -+ cpu = task_cpu(p); -+ if ((cpu != smp_processor_id()) && task_curr(p)) -+ smp_send_reschedule(cpu); -+ preempt_enable(); -+} -+EXPORT_SYMBOL_GPL(kick_process); -+#endif -+ -+#define rq_idle(rq) ((rq)->rq_prio == PRIO_LIMIT) -+ -+/* -+ * RT tasks preempt purely on priority. SCHED_NORMAL tasks preempt on the -+ * basis of earlier deadlines. SCHED_IDLEPRIO don't preempt anything else or -+ * between themselves, they cooperatively multitask. An idle rq scores as -+ * prio PRIO_LIMIT so it is always preempted. -+ */ -+static inline bool -+can_preempt(struct task_struct *p, int prio, u64 deadline) -+{ -+ /* Better static priority RT task or better policy preemption */ -+ if (p->prio < prio) -+ return true; -+ if (p->prio > prio) -+ return false; -+ /* SCHED_NORMAL, BATCH and ISO will preempt based on deadline */ -+ if (!deadline_before(p->deadline, deadline)) -+ return false; -+ return true; -+} -+ -+#ifdef CONFIG_SMP -+#define cpu_online_map (*(cpumask_t *)cpu_online_mask) -+#ifdef CONFIG_HOTPLUG_CPU -+/* -+ * Check to see if there is a task that is affined only to offline CPUs but -+ * still wants runtime. This happens to kernel threads during suspend/halt and -+ * disabling of CPUs. -+ */ -+static inline bool online_cpus(struct task_struct *p) -+{ -+ return (likely(cpus_intersects(cpu_online_map, p->cpus_allowed))); -+} -+#else /* CONFIG_HOTPLUG_CPU */ -+/* All available CPUs are always online without hotplug. */ -+static inline bool online_cpus(struct task_struct *p) -+{ -+ return true; -+} -+#endif -+ -+/* -+ * Check to see if p can run on cpu, and if not, whether there are any online -+ * CPUs it can run on instead. -+ */ -+static inline bool needs_other_cpu(struct task_struct *p, int cpu) -+{ -+ if (unlikely(!cpu_isset(cpu, p->cpus_allowed))) -+ return true; -+ return false; -+} -+ -+/* -+ * When all else is equal, still prefer this_rq. -+ */ -+static void try_preempt(struct task_struct *p, struct rq *this_rq) -+{ -+ struct rq *highest_prio_rq = NULL; -+ int cpu, highest_prio; -+ u64 latest_deadline; -+ cpumask_t tmp; -+ -+ /* -+ * We clear the sticky flag here because for a task to have called -+ * try_preempt with the sticky flag enabled means some complicated -+ * re-scheduling has occurred and we should ignore the sticky flag. -+ */ -+ clear_sticky(p); -+ -+ if (suitable_idle_cpus(p)) { -+ resched_best_idle(p); -+ return; -+ } -+ -+ /* IDLEPRIO tasks never preempt anything but idle */ -+ if (p->policy == SCHED_IDLEPRIO) -+ return; -+ -+ if (likely(online_cpus(p))) -+ cpus_and(tmp, cpu_online_map, p->cpus_allowed); -+ else -+ return; -+ -+ highest_prio = latest_deadline = 0; -+ -+ for_each_cpu_mask(cpu, tmp) { -+ struct rq *rq; -+ int rq_prio; -+ -+ rq = cpu_rq(cpu); -+ rq_prio = rq->rq_prio; -+ if (rq_prio < highest_prio) -+ continue; -+ -+ if (rq_prio > highest_prio || -+ deadline_after(rq->rq_deadline, latest_deadline)) { -+ latest_deadline = rq->rq_deadline; -+ highest_prio = rq_prio; -+ highest_prio_rq = rq; -+ } -+ } -+ -+ if (likely(highest_prio_rq)) { -+ if (can_preempt(p, highest_prio, highest_prio_rq->rq_deadline)) -+ resched_task(highest_prio_rq->curr); -+ } -+} -+#else /* CONFIG_SMP */ -+static inline bool needs_other_cpu(struct task_struct *p, int cpu) -+{ -+ return false; -+} -+ -+static void try_preempt(struct task_struct *p, struct rq *this_rq) -+{ -+ if (p->policy == SCHED_IDLEPRIO) -+ return; -+ if (can_preempt(p, uprq->rq_prio, uprq->rq_deadline)) -+ resched_task(uprq->curr); -+} -+#endif /* CONFIG_SMP */ -+ -+static void -+ttwu_stat(struct task_struct *p, int cpu, int wake_flags) -+{ -+#ifdef CONFIG_SCHEDSTATS -+ struct rq *rq = this_rq(); -+ -+#ifdef CONFIG_SMP -+ int this_cpu = smp_processor_id(); -+ -+ if (cpu == this_cpu) -+ schedstat_inc(rq, ttwu_local); -+ else { -+ struct sched_domain *sd; -+ -+ rcu_read_lock(); -+ for_each_domain(this_cpu, sd) { -+ if (cpumask_test_cpu(cpu, sched_domain_span(sd))) { -+ schedstat_inc(sd, ttwu_wake_remote); -+ break; -+ } -+ } -+ rcu_read_unlock(); -+ } -+ -+#endif /* CONFIG_SMP */ -+ -+ schedstat_inc(rq, ttwu_count); -+#endif /* CONFIG_SCHEDSTATS */ -+} -+ -+static inline void ttwu_activate(struct task_struct *p, struct rq *rq, -+ bool is_sync) -+{ -+ activate_task(p, rq); -+ -+ /* -+ * Sync wakeups (i.e. those types of wakeups where the waker -+ * has indicated that it will leave the CPU in short order) -+ * don't trigger a preemption if there are no idle cpus, -+ * instead waiting for current to deschedule. -+ */ -+ if (!is_sync || suitable_idle_cpus(p)) -+ try_preempt(p, rq); -+} -+ -+static inline void ttwu_post_activation(struct task_struct *p, struct rq *rq, -+ bool success) -+{ -+ trace_sched_wakeup(p, success); -+ p->state = TASK_RUNNING; -+ -+ /* -+ * if a worker is waking up, notify workqueue. Note that on BFS, we -+ * don't really know what cpu it will be, so we fake it for -+ * wq_worker_waking_up :/ -+ */ -+ if ((p->flags & PF_WQ_WORKER) && success) -+ wq_worker_waking_up(p, cpu_of(rq)); -+} -+ -+#ifdef CONFIG_SMP -+void scheduler_ipi(void) -+{ -+} -+#endif /* CONFIG_SMP */ -+ -+/* -+ * wake flags -+ */ -+#define WF_SYNC 0x01 /* waker goes to sleep after wakeup */ -+#define WF_FORK 0x02 /* child wakeup after fork */ -+#define WF_MIGRATED 0x4 /* internal use, task got migrated */ -+ -+/*** -+ * try_to_wake_up - wake up a thread -+ * @p: the thread to be awakened -+ * @state: the mask of task states that can be woken -+ * @wake_flags: wake modifier flags (WF_*) -+ * -+ * Put it on the run-queue if it's not already there. The "current" -+ * thread is always on the run-queue (except when the actual -+ * re-schedule is in progress), and as such you're allowed to do -+ * the simpler "current->state = TASK_RUNNING" to mark yourself -+ * runnable without the overhead of this. -+ * -+ * Returns %true if @p was woken up, %false if it was already running -+ * or @state didn't match @p's state. -+ */ -+static bool try_to_wake_up(struct task_struct *p, unsigned int state, -+ int wake_flags) -+{ -+ bool success = false; -+ unsigned long flags; -+ struct rq *rq; -+ int cpu; -+ -+ get_cpu(); -+ -+ /* This barrier is undocumented, probably for p->state? くそ */ -+ smp_wmb(); -+ -+ /* -+ * No need to do time_lock_grq as we only need to update the rq clock -+ * if we activate the task -+ */ -+ rq = task_grq_lock(p, &flags); -+ cpu = task_cpu(p); -+ -+ /* state is a volatile long, どうして、分からない */ -+ if (!((unsigned int)p->state & state)) -+ goto out_unlock; -+ -+ if (task_queued(p) || task_running(p)) -+ goto out_running; -+ -+ ttwu_activate(p, rq, wake_flags & WF_SYNC); -+ success = true; -+ -+out_running: -+ ttwu_post_activation(p, rq, success); -+out_unlock: -+ task_grq_unlock(&flags); -+ -+ ttwu_stat(p, cpu, wake_flags); -+ -+ put_cpu(); -+ -+ return success; -+} -+ -+/** -+ * try_to_wake_up_local - try to wake up a local task with grq lock held -+ * @p: the thread to be awakened -+ * -+ * Put @p on the run-queue if it's not already there. The caller must -+ * ensure that grq is locked and, @p is not the current task. -+ * grq stays locked over invocation. -+ */ -+static void try_to_wake_up_local(struct task_struct *p) -+{ -+ struct rq *rq = task_rq(p); -+ bool success = false; -+ -+ lockdep_assert_held(&grq.lock); -+ -+ if (!(p->state & TASK_NORMAL)) -+ return; -+ -+ if (!task_queued(p)) { -+ if (likely(!task_running(p))) { -+ schedstat_inc(rq, ttwu_count); -+ schedstat_inc(rq, ttwu_local); -+ } -+ ttwu_activate(p, rq, false); -+ ttwu_stat(p, smp_processor_id(), 0); -+ success = true; -+ } -+ ttwu_post_activation(p, rq, success); -+} -+ -+/** -+ * wake_up_process - Wake up a specific process -+ * @p: The process to be woken up. -+ * -+ * Attempt to wake up the nominated process and move it to the set of runnable -+ * processes. Returns 1 if the process was woken up, 0 if it was already -+ * running. -+ * -+ * It may be assumed that this function implies a write memory barrier before -+ * changing the task state if and only if any tasks are woken up. -+ */ -+int wake_up_process(struct task_struct *p) -+{ -+ WARN_ON(task_is_stopped_or_traced(p)); -+ return try_to_wake_up(p, TASK_NORMAL, 0); -+} -+EXPORT_SYMBOL(wake_up_process); -+ -+int wake_up_state(struct task_struct *p, unsigned int state) -+{ -+ return try_to_wake_up(p, state, 0); -+} -+ -+static void time_slice_expired(struct task_struct *p); -+ -+/* -+ * Perform scheduler related setup for a newly forked process p. -+ * p is forked by current. -+ */ -+void sched_fork(struct task_struct *p) -+{ -+#ifdef CONFIG_PREEMPT_NOTIFIERS -+ INIT_HLIST_HEAD(&p->preempt_notifiers); -+#endif -+ /* -+ * The process state is set to the same value of the process executing -+ * do_fork() code. That is running. This guarantees that nobody will -+ * actually run it, and a signal or other external event cannot wake -+ * it up and insert it on the runqueue either. -+ */ -+ -+ /* Should be reset in fork.c but done here for ease of bfs patching */ -+ p->utime = -+ p->stime = -+ p->utimescaled = -+ p->stimescaled = -+ p->sched_time = -+ p->stime_pc = -+ p->utime_pc = 0; -+ -+ /* -+ * Revert to default priority/policy on fork if requested. -+ */ -+ if (unlikely(p->sched_reset_on_fork)) { -+ if (p->policy == SCHED_FIFO || p->policy == SCHED_RR) { -+ p->policy = SCHED_NORMAL; -+ p->normal_prio = normal_prio(p); -+ } -+ -+ if (PRIO_TO_NICE(p->static_prio) < 0) { -+ p->static_prio = NICE_TO_PRIO(0); -+ p->normal_prio = p->static_prio; -+ } -+ -+ /* -+ * We don't need the reset flag anymore after the fork. It has -+ * fulfilled its duty: -+ */ -+ p->sched_reset_on_fork = 0; -+ } -+ -+ INIT_LIST_HEAD(&p->run_list); -+#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) -+ if (unlikely(sched_info_on())) -+ memset(&p->sched_info, 0, sizeof(p->sched_info)); -+#endif -+ p->on_cpu = false; -+ clear_sticky(p); -+ -+#ifdef CONFIG_PREEMPT_COUNT -+ /* Want to start with kernel preemption disabled. */ -+ task_thread_info(p)->preempt_count = 1; -+#endif -+} -+ -+/* -+ * wake_up_new_task - wake up a newly created task for the first time. -+ * -+ * This function will do some initial scheduler statistics housekeeping -+ * that must be done for every newly created context, then puts the task -+ * on the runqueue and wakes it. -+ */ -+void wake_up_new_task(struct task_struct *p) -+{ -+ struct task_struct *parent; -+ unsigned long flags; -+ struct rq *rq; -+ -+ parent = p->parent; -+ rq = task_grq_lock(p, &flags); -+ -+ /* -+ * Reinit new task deadline as its creator deadline could have changed -+ * since call to dup_task_struct(). -+ */ -+ p->deadline = rq->rq_deadline; -+ -+ /* -+ * If the task is a new process, current and parent are the same. If -+ * the task is a new thread in the thread group, it will have much more -+ * in common with current than with the parent. -+ */ -+ set_task_cpu(p, task_cpu(rq->curr)); -+ -+ /* -+ * Make sure we do not leak PI boosting priority to the child. -+ */ -+ p->prio = rq->curr->normal_prio; -+ -+ activate_task(p, rq); -+ trace_sched_wakeup_new(p, 1); -+ if (unlikely(p->policy == SCHED_FIFO)) -+ goto after_ts_init; -+ -+ /* -+ * Share the timeslice between parent and child, thus the -+ * total amount of pending timeslices in the system doesn't change, -+ * resulting in more scheduling fairness. If it's negative, it won't -+ * matter since that's the same as being 0. current's time_slice is -+ * actually in rq_time_slice when it's running, as is its last_ran -+ * value. rq->rq_deadline is only modified within schedule() so it -+ * is always equal to current->deadline. -+ */ -+ p->last_ran = rq->rq_last_ran; -+ if (likely(rq->rq_time_slice >= RESCHED_US * 2)) { -+ rq->rq_time_slice /= 2; -+ p->time_slice = rq->rq_time_slice; -+after_ts_init: -+ if (rq->curr == parent && !suitable_idle_cpus(p)) { -+ /* -+ * The VM isn't cloned, so we're in a good position to -+ * do child-runs-first in anticipation of an exec. This -+ * usually avoids a lot of COW overhead. -+ */ -+ set_tsk_need_resched(parent); -+ } else -+ try_preempt(p, rq); -+ } else { -+ if (rq->curr == parent) { -+ /* -+ * Forking task has run out of timeslice. Reschedule it and -+ * start its child with a new time slice and deadline. The -+ * child will end up running first because its deadline will -+ * be slightly earlier. -+ */ -+ rq->rq_time_slice = 0; -+ set_tsk_need_resched(parent); -+ } -+ time_slice_expired(p); -+ } -+ task_grq_unlock(&flags); -+} -+ -+#ifdef CONFIG_PREEMPT_NOTIFIERS -+ -+/** -+ * preempt_notifier_register - tell me when current is being preempted & rescheduled -+ * @notifier: notifier struct to register -+ */ -+void preempt_notifier_register(struct preempt_notifier *notifier) -+{ -+ hlist_add_head(¬ifier->link, ¤t->preempt_notifiers); -+} -+EXPORT_SYMBOL_GPL(preempt_notifier_register); -+ -+/** -+ * preempt_notifier_unregister - no longer interested in preemption notifications -+ * @notifier: notifier struct to unregister -+ * -+ * This is safe to call from within a preemption notifier. -+ */ -+void preempt_notifier_unregister(struct preempt_notifier *notifier) -+{ -+ hlist_del(¬ifier->link); -+} -+EXPORT_SYMBOL_GPL(preempt_notifier_unregister); -+ -+static void fire_sched_in_preempt_notifiers(struct task_struct *curr) -+{ -+ struct preempt_notifier *notifier; -+ -+ hlist_for_each_entry(notifier, &curr->preempt_notifiers, link) -+ notifier->ops->sched_in(notifier, raw_smp_processor_id()); -+} -+ -+static void -+fire_sched_out_preempt_notifiers(struct task_struct *curr, -+ struct task_struct *next) -+{ -+ struct preempt_notifier *notifier; -+ -+ hlist_for_each_entry(notifier, &curr->preempt_notifiers, link) -+ notifier->ops->sched_out(notifier, next); -+} -+ -+#else /* !CONFIG_PREEMPT_NOTIFIERS */ -+ -+static void fire_sched_in_preempt_notifiers(struct task_struct *curr) -+{ -+} -+ -+static void -+fire_sched_out_preempt_notifiers(struct task_struct *curr, -+ struct task_struct *next) -+{ -+} -+ -+#endif /* CONFIG_PREEMPT_NOTIFIERS */ -+ -+/** -+ * prepare_task_switch - prepare to switch tasks -+ * @rq: the runqueue preparing to switch -+ * @next: the task we are going to switch to. -+ * -+ * This is called with the rq lock held and interrupts off. It must -+ * be paired with a subsequent finish_task_switch after the context -+ * switch. -+ * -+ * prepare_task_switch sets up locking and calls architecture specific -+ * hooks. -+ */ -+static inline void -+prepare_task_switch(struct rq *rq, struct task_struct *prev, -+ struct task_struct *next) -+{ -+ sched_info_switch(prev, next); -+ perf_event_task_sched_out(prev, next); -+ fire_sched_out_preempt_notifiers(prev, next); -+ prepare_lock_switch(rq, next); -+ prepare_arch_switch(next); -+ trace_sched_switch(prev, next); -+} -+ -+/** -+ * finish_task_switch - clean up after a task-switch -+ * @rq: runqueue associated with task-switch -+ * @prev: the thread we just switched away from. -+ * -+ * finish_task_switch must be called after the context switch, paired -+ * with a prepare_task_switch call before the context switch. -+ * finish_task_switch will reconcile locking set up by prepare_task_switch, -+ * and do any other architecture-specific cleanup actions. -+ * -+ * Note that we may have delayed dropping an mm in context_switch(). If -+ * so, we finish that here outside of the runqueue lock. (Doing it -+ * with the lock held can cause deadlocks; see schedule() for -+ * details.) -+ */ -+static inline void finish_task_switch(struct rq *rq, struct task_struct *prev) -+ __releases(grq.lock) -+{ -+ struct mm_struct *mm = rq->prev_mm; -+ long prev_state; -+ -+ rq->prev_mm = NULL; -+ -+ /* -+ * A task struct has one reference for the use as "current". -+ * If a task dies, then it sets TASK_DEAD in tsk->state and calls -+ * schedule one last time. The schedule call will never return, and -+ * the scheduled task must drop that reference. -+ * The test for TASK_DEAD must occur while the runqueue locks are -+ * still held, otherwise prev could be scheduled on another cpu, die -+ * there before we look at prev->state, and then the reference would -+ * be dropped twice. -+ * Manfred Spraul -+ */ -+ prev_state = prev->state; -+ vtime_task_switch(prev); -+ finish_arch_switch(prev); -+ perf_event_task_sched_in(prev, current); -+ finish_lock_switch(rq, prev); -+ finish_arch_post_lock_switch(); -+ -+ fire_sched_in_preempt_notifiers(current); -+ if (mm) -+ mmdrop(mm); -+ if (unlikely(prev_state == TASK_DEAD)) { -+ /* -+ * Remove function-return probe instances associated with this -+ * task and put them back on the free list. -+ */ -+ kprobe_flush_task(prev); -+ put_task_struct(prev); -+ } -+} -+ -+/** -+ * schedule_tail - first thing a freshly forked thread must call. -+ * @prev: the thread we just switched away from. -+ */ -+asmlinkage void schedule_tail(struct task_struct *prev) -+ __releases(grq.lock) -+{ -+ struct rq *rq = this_rq(); -+ -+ finish_task_switch(rq, prev); -+#ifdef __ARCH_WANT_UNLOCKED_CTXSW -+ /* In this case, finish_task_switch does not reenable preemption */ -+ preempt_enable(); -+#endif -+ if (current->set_child_tid) -+ put_user(current->pid, current->set_child_tid); -+} -+ -+/* -+ * context_switch - switch to the new MM and the new -+ * thread's register state. -+ */ -+static inline void -+context_switch(struct rq *rq, struct task_struct *prev, -+ struct task_struct *next) -+{ -+ struct mm_struct *mm, *oldmm; -+ -+ prepare_task_switch(rq, prev, next); -+ -+ mm = next->mm; -+ oldmm = prev->active_mm; -+ /* -+ * For paravirt, this is coupled with an exit in switch_to to -+ * combine the page table reload and the switch backend into -+ * one hypercall. -+ */ -+ arch_start_context_switch(prev); -+ -+ if (!mm) { -+ next->active_mm = oldmm; -+ atomic_inc(&oldmm->mm_count); -+ enter_lazy_tlb(oldmm, next); -+ } else -+ switch_mm(oldmm, mm, next); -+ -+ if (!prev->mm) { -+ prev->active_mm = NULL; -+ rq->prev_mm = oldmm; -+ } -+ /* -+ * Since the runqueue lock will be released by the next -+ * task (which is an invalid locking op but in the case -+ * of the scheduler it's an obvious special-case), so we -+ * do an early lockdep release here: -+ */ -+#ifndef __ARCH_WANT_UNLOCKED_CTXSW -+ spin_release(&grq.lock.dep_map, 1, _THIS_IP_); -+#endif -+ -+ /* Here we just switch the register state and the stack. */ -+ context_tracking_task_switch(prev, next); -+ switch_to(prev, next, prev); -+ -+ barrier(); -+ /* -+ * this_rq must be evaluated again because prev may have moved -+ * CPUs since it called schedule(), thus the 'rq' on its stack -+ * frame will be invalid. -+ */ -+ finish_task_switch(this_rq(), prev); -+} -+ -+/* -+ * nr_running, nr_uninterruptible and nr_context_switches: -+ * -+ * externally visible scheduler statistics: current number of runnable -+ * threads, total number of context switches performed since bootup. All are -+ * measured without grabbing the grq lock but the occasional inaccurate result -+ * doesn't matter so long as it's positive. -+ */ -+unsigned long nr_running(void) -+{ -+ long nr = grq.nr_running; -+ -+ if (unlikely(nr < 0)) -+ nr = 0; -+ return (unsigned long)nr; -+} -+ -+static unsigned long nr_uninterruptible(void) -+{ -+ long nu = grq.nr_uninterruptible; -+ -+ if (unlikely(nu < 0)) -+ nu = 0; -+ return nu; -+} -+ -+unsigned long long nr_context_switches(void) -+{ -+ long long ns = grq.nr_switches; -+ -+ /* This is of course impossible */ -+ if (unlikely(ns < 0)) -+ ns = 1; -+ return (unsigned long long)ns; -+} -+ -+unsigned long nr_iowait(void) -+{ -+ unsigned long i, sum = 0; -+ -+ for_each_possible_cpu(i) -+ sum += atomic_read(&cpu_rq(i)->nr_iowait); -+ -+ return sum; -+} -+ -+unsigned long nr_iowait_cpu(int cpu) -+{ -+ struct rq *this = cpu_rq(cpu); -+ return atomic_read(&this->nr_iowait); -+} -+ -+unsigned long nr_active(void) -+{ -+ return nr_running() + nr_uninterruptible(); -+} -+ -+/* Beyond a task running on this CPU, load is equal everywhere on BFS */ -+unsigned long this_cpu_load(void) -+{ -+ return this_rq()->rq_running + -+ ((queued_notrunning() + nr_uninterruptible()) / grq.noc); -+} -+ -+/* Variables and functions for calc_load */ -+static unsigned long calc_load_update; -+unsigned long avenrun[3]; -+EXPORT_SYMBOL(avenrun); -+ -+/** -+ * get_avenrun - get the load average array -+ * @loads: pointer to dest load array -+ * @offset: offset to add -+ * @shift: shift count to shift the result left -+ * -+ * These values are estimates at best, so no need for locking. -+ */ -+void get_avenrun(unsigned long *loads, unsigned long offset, int shift) -+{ -+ loads[0] = (avenrun[0] + offset) << shift; -+ loads[1] = (avenrun[1] + offset) << shift; -+ loads[2] = (avenrun[2] + offset) << shift; -+} -+ -+static unsigned long -+calc_load(unsigned long load, unsigned long exp, unsigned long active) -+{ -+ load *= exp; -+ load += active * (FIXED_1 - exp); -+ return load >> FSHIFT; -+} -+ -+/* -+ * calc_load - update the avenrun load estimates every LOAD_FREQ seconds. -+ */ -+void calc_global_load(unsigned long ticks) -+{ -+ long active; -+ -+ if (time_before(jiffies, calc_load_update)) -+ return; -+ active = nr_active() * FIXED_1; -+ -+ avenrun[0] = calc_load(avenrun[0], EXP_1, active); -+ avenrun[1] = calc_load(avenrun[1], EXP_5, active); -+ avenrun[2] = calc_load(avenrun[2], EXP_15, active); -+ -+ calc_load_update = jiffies + LOAD_FREQ; -+} -+ -+DEFINE_PER_CPU(struct kernel_stat, kstat); -+DEFINE_PER_CPU(struct kernel_cpustat, kernel_cpustat); -+ -+EXPORT_PER_CPU_SYMBOL(kstat); -+EXPORT_PER_CPU_SYMBOL(kernel_cpustat); -+ -+#ifdef CONFIG_IRQ_TIME_ACCOUNTING -+ -+/* -+ * There are no locks covering percpu hardirq/softirq time. -+ * They are only modified in account_system_vtime, on corresponding CPU -+ * with interrupts disabled. So, writes are safe. -+ * They are read and saved off onto struct rq in update_rq_clock(). -+ * This may result in other CPU reading this CPU's irq time and can -+ * race with irq/account_system_vtime on this CPU. We would either get old -+ * or new value with a side effect of accounting a slice of irq time to wrong -+ * task when irq is in progress while we read rq->clock. That is a worthy -+ * compromise in place of having locks on each irq in account_system_time. -+ */ -+static DEFINE_PER_CPU(u64, cpu_hardirq_time); -+static DEFINE_PER_CPU(u64, cpu_softirq_time); -+ -+static DEFINE_PER_CPU(u64, irq_start_time); -+static int sched_clock_irqtime; -+ -+void enable_sched_clock_irqtime(void) -+{ -+ sched_clock_irqtime = 1; -+} -+ -+void disable_sched_clock_irqtime(void) -+{ -+ sched_clock_irqtime = 0; -+} -+ -+#ifndef CONFIG_64BIT -+static DEFINE_PER_CPU(seqcount_t, irq_time_seq); -+ -+static inline void irq_time_write_begin(void) -+{ -+ __this_cpu_inc(irq_time_seq.sequence); -+ smp_wmb(); -+} -+ -+static inline void irq_time_write_end(void) -+{ -+ smp_wmb(); -+ __this_cpu_inc(irq_time_seq.sequence); -+} -+ -+static inline u64 irq_time_read(int cpu) -+{ -+ u64 irq_time; -+ unsigned seq; -+ -+ do { -+ seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu)); -+ irq_time = per_cpu(cpu_softirq_time, cpu) + -+ per_cpu(cpu_hardirq_time, cpu); -+ } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq)); -+ -+ return irq_time; -+} -+#else /* CONFIG_64BIT */ -+static inline void irq_time_write_begin(void) -+{ -+} -+ -+static inline void irq_time_write_end(void) -+{ -+} -+ -+static inline u64 irq_time_read(int cpu) -+{ -+ return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu); -+} -+#endif /* CONFIG_64BIT */ -+ -+/* -+ * Called before incrementing preempt_count on {soft,}irq_enter -+ * and before decrementing preempt_count on {soft,}irq_exit. -+ */ -+void irqtime_account_irq(struct task_struct *curr) -+{ -+ unsigned long flags; -+ s64 delta; -+ int cpu; -+ -+ if (!sched_clock_irqtime) -+ return; -+ -+ local_irq_save(flags); -+ -+ cpu = smp_processor_id(); -+ delta = sched_clock_cpu(cpu) - __this_cpu_read(irq_start_time); -+ __this_cpu_add(irq_start_time, delta); -+ -+ irq_time_write_begin(); -+ /* -+ * We do not account for softirq time from ksoftirqd here. -+ * We want to continue accounting softirq time to ksoftirqd thread -+ * in that case, so as not to confuse scheduler with a special task -+ * that do not consume any time, but still wants to run. -+ */ -+ if (hardirq_count()) -+ __this_cpu_add(cpu_hardirq_time, delta); -+ else if (in_serving_softirq() && curr != this_cpu_ksoftirqd()) -+ __this_cpu_add(cpu_softirq_time, delta); -+ -+ irq_time_write_end(); -+ local_irq_restore(flags); -+} -+EXPORT_SYMBOL_GPL(irqtime_account_irq); -+ -+#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ -+ -+#ifdef CONFIG_PARAVIRT -+static inline u64 steal_ticks(u64 steal) -+{ -+ if (unlikely(steal > NSEC_PER_SEC)) -+ return div_u64(steal, TICK_NSEC); -+ -+ return __iter_div_u64_rem(steal, TICK_NSEC, &steal); -+} -+#endif -+ -+static void update_rq_clock_task(struct rq *rq, s64 delta) -+{ -+/* -+ * In theory, the compile should just see 0 here, and optimize out the call -+ * to sched_rt_avg_update. But I don't trust it... -+ */ -+#ifdef CONFIG_IRQ_TIME_ACCOUNTING -+ s64 irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time; -+ -+ /* -+ * Since irq_time is only updated on {soft,}irq_exit, we might run into -+ * this case when a previous update_rq_clock() happened inside a -+ * {soft,}irq region. -+ * -+ * When this happens, we stop ->clock_task and only update the -+ * prev_irq_time stamp to account for the part that fit, so that a next -+ * update will consume the rest. This ensures ->clock_task is -+ * monotonic. -+ * -+ * It does however cause some slight miss-attribution of {soft,}irq -+ * time, a more accurate solution would be to update the irq_time using -+ * the current rq->clock timestamp, except that would require using -+ * atomic ops. -+ */ -+ if (irq_delta > delta) -+ irq_delta = delta; -+ -+ rq->prev_irq_time += irq_delta; -+ delta -= irq_delta; -+#endif -+#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING -+ if (static_key_false((¶virt_steal_rq_enabled))) { -+ s64 steal = paravirt_steal_clock(cpu_of(rq)); -+ u64 st; -+ -+ steal -= rq->prev_steal_time_rq; -+ -+ if (unlikely(steal > delta)) -+ steal = delta; -+ -+ st = steal_ticks(steal); -+ steal = st * TICK_NSEC; -+ -+ rq->prev_steal_time_rq += steal; -+ -+ delta -= steal; -+ } -+#endif -+ -+ rq->clock_task += delta; -+} -+ -+#ifndef nsecs_to_cputime -+# define nsecs_to_cputime(__nsecs) nsecs_to_jiffies(__nsecs) -+#endif -+ -+#ifdef CONFIG_IRQ_TIME_ACCOUNTING -+static void irqtime_account_hi_si(void) -+{ -+ u64 *cpustat = kcpustat_this_cpu->cpustat; -+ u64 latest_ns; -+ -+ latest_ns = nsecs_to_cputime64(this_cpu_read(cpu_hardirq_time)); -+ if (latest_ns > cpustat[CPUTIME_IRQ]) -+ cpustat[CPUTIME_IRQ] += (__force u64)cputime_one_jiffy; -+ -+ latest_ns = nsecs_to_cputime64(this_cpu_read(cpu_softirq_time)); -+ if (latest_ns > cpustat[CPUTIME_SOFTIRQ]) -+ cpustat[CPUTIME_SOFTIRQ] += (__force u64)cputime_one_jiffy; -+} -+#else /* CONFIG_IRQ_TIME_ACCOUNTING */ -+ -+#define sched_clock_irqtime (0) -+ -+static inline void irqtime_account_hi_si(void) -+{ -+} -+#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ -+ -+static __always_inline bool steal_account_process_tick(void) -+{ -+#ifdef CONFIG_PARAVIRT -+ if (static_key_false(¶virt_steal_enabled)) { -+ u64 steal, st = 0; -+ -+ steal = paravirt_steal_clock(smp_processor_id()); -+ steal -= this_rq()->prev_steal_time; -+ -+ st = steal_ticks(steal); -+ this_rq()->prev_steal_time += st * TICK_NSEC; -+ -+ account_steal_time(st); -+ return st; -+ } -+#endif -+ return false; -+} -+ -+/* -+ * Accumulate raw cputime values of dead tasks (sig->[us]time) and live -+ * tasks (sum on group iteration) belonging to @tsk's group. -+ */ -+void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times) -+{ -+ struct signal_struct *sig = tsk->signal; -+ cputime_t utime, stime; -+ struct task_struct *t; -+ -+ times->utime = sig->utime; -+ times->stime = sig->stime; -+ times->sum_exec_runtime = sig->sum_sched_runtime; -+ -+ rcu_read_lock(); -+ /* make sure we can trust tsk->thread_group list */ -+ if (!likely(pid_alive(tsk))) -+ goto out; -+ -+ t = tsk; -+ do { -+ task_cputime(t, &utime, &stime); -+ times->utime += utime; -+ times->stime += stime; -+ times->sum_exec_runtime += task_sched_runtime(t); -+ } while_each_thread(tsk, t); -+out: -+ rcu_read_unlock(); -+} -+ -+/* -+ * On each tick, see what percentage of that tick was attributed to each -+ * component and add the percentage to the _pc values. Once a _pc value has -+ * accumulated one tick's worth, account for that. This means the total -+ * percentage of load components will always be 128 (pseudo 100) per tick. -+ */ -+static void pc_idle_time(struct rq *rq, struct task_struct *idle, unsigned long pc) -+{ -+ u64 *cpustat = kcpustat_this_cpu->cpustat; -+ -+ if (atomic_read(&rq->nr_iowait) > 0) { -+ rq->iowait_pc += pc; -+ if (rq->iowait_pc >= 128) { -+ cpustat[CPUTIME_IOWAIT] += (__force u64)cputime_one_jiffy * rq->iowait_pc / 128; -+ rq->iowait_pc %= 128; -+ } -+ } else { -+ rq->idle_pc += pc; -+ if (rq->idle_pc >= 128) { -+ cpustat[CPUTIME_IDLE] += (__force u64)cputime_one_jiffy * rq->idle_pc / 128; -+ rq->idle_pc %= 128; -+ } -+ } -+ acct_update_integrals(idle); -+} -+ -+static void -+pc_system_time(struct rq *rq, struct task_struct *p, int hardirq_offset, -+ unsigned long pc, unsigned long ns) -+{ -+ u64 *cpustat = kcpustat_this_cpu->cpustat; -+ cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); -+ -+ p->stime_pc += pc; -+ if (p->stime_pc >= 128) { -+ int jiffs = p->stime_pc / 128; -+ -+ p->stime_pc %= 128; -+ p->stime += (__force u64)cputime_one_jiffy * jiffs; -+ p->stimescaled += one_jiffy_scaled * jiffs; -+ account_group_system_time(p, cputime_one_jiffy * jiffs); -+ } -+ p->sched_time += ns; -+ /* -+ * Do not update the cputimer if the task is already released by -+ * release_task(). -+ * -+ * This could be executed if a tick happens when a task is inside -+ * do_exit() between the call to release_task() and its final -+ * schedule() call for autoreaping tasks. -+ */ -+ if (likely(p->sighand)) -+ account_group_exec_runtime(p, ns); -+ -+ if (hardirq_count() - hardirq_offset) { -+ rq->irq_pc += pc; -+ if (rq->irq_pc >= 128) { -+ cpustat[CPUTIME_IRQ] += (__force u64)cputime_one_jiffy * rq->irq_pc / 128; -+ rq->irq_pc %= 128; -+ } -+ } else if (in_serving_softirq()) { -+ rq->softirq_pc += pc; -+ if (rq->softirq_pc >= 128) { -+ cpustat[CPUTIME_SOFTIRQ] += (__force u64)cputime_one_jiffy * rq->softirq_pc / 128; -+ rq->softirq_pc %= 128; -+ } -+ } else { -+ rq->system_pc += pc; -+ if (rq->system_pc >= 128) { -+ cpustat[CPUTIME_SYSTEM] += (__force u64)cputime_one_jiffy * rq->system_pc / 128; -+ rq->system_pc %= 128; -+ } -+ } -+ acct_update_integrals(p); -+} -+ -+static void pc_user_time(struct rq *rq, struct task_struct *p, -+ unsigned long pc, unsigned long ns) -+{ -+ u64 *cpustat = kcpustat_this_cpu->cpustat; -+ cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy); -+ -+ p->utime_pc += pc; -+ if (p->utime_pc >= 128) { -+ int jiffs = p->utime_pc / 128; -+ -+ p->utime_pc %= 128; -+ p->utime += (__force u64)cputime_one_jiffy * jiffs; -+ p->utimescaled += one_jiffy_scaled * jiffs; -+ account_group_user_time(p, cputime_one_jiffy * jiffs); -+ } -+ p->sched_time += ns; -+ /* -+ * Do not update the cputimer if the task is already released by -+ * release_task(). -+ * -+ * it would preferable to defer the autoreap release_task -+ * after the last context switch but harder to do. -+ */ -+ if (likely(p->sighand)) -+ account_group_exec_runtime(p, ns); -+ -+ if (this_cpu_ksoftirqd() == p) { -+ /* -+ * ksoftirqd time do not get accounted in cpu_softirq_time. -+ * So, we have to handle it separately here. -+ */ -+ rq->softirq_pc += pc; -+ if (rq->softirq_pc >= 128) { -+ cpustat[CPUTIME_SOFTIRQ] += (__force u64)cputime_one_jiffy * rq->softirq_pc / 128; -+ rq->softirq_pc %= 128; -+ } -+ } -+ -+ if (TASK_NICE(p) > 0 || idleprio_task(p)) { -+ rq->nice_pc += pc; -+ if (rq->nice_pc >= 128) { -+ cpustat[CPUTIME_NICE] += (__force u64)cputime_one_jiffy * rq->nice_pc / 128; -+ rq->nice_pc %= 128; -+ } -+ } else { -+ rq->user_pc += pc; -+ if (rq->user_pc >= 128) { -+ cpustat[CPUTIME_USER] += (__force u64)cputime_one_jiffy * rq->user_pc / 128; -+ rq->user_pc %= 128; -+ } -+ } -+ acct_update_integrals(p); -+} -+ -+/* -+ * Convert nanoseconds to pseudo percentage of one tick. Use 128 for fast -+ * shifts instead of 100 -+ */ -+#define NS_TO_PC(NS) (NS * 128 / JIFFY_NS) -+ -+/* -+ * This is called on clock ticks. -+ * Bank in p->sched_time the ns elapsed since the last tick or switch. -+ * CPU scheduler quota accounting is also performed here in microseconds. -+ */ -+static void -+update_cpu_clock_tick(struct rq *rq, struct task_struct *p) -+{ -+ long account_ns = rq->clock_task - rq->rq_last_ran; -+ struct task_struct *idle = rq->idle; -+ unsigned long account_pc; -+ -+ if (unlikely(account_ns < 0) || steal_account_process_tick()) -+ goto ts_account; -+ -+ account_pc = NS_TO_PC(account_ns); -+ -+ /* Accurate tick timekeeping */ -+ if (user_mode(get_irq_regs())) -+ pc_user_time(rq, p, account_pc, account_ns); -+ else if (p != idle || (irq_count() != HARDIRQ_OFFSET)) -+ pc_system_time(rq, p, HARDIRQ_OFFSET, -+ account_pc, account_ns); -+ else -+ pc_idle_time(rq, idle, account_pc); -+ -+ if (sched_clock_irqtime) -+ irqtime_account_hi_si(); -+ -+ts_account: -+ /* time_slice accounting is done in usecs to avoid overflow on 32bit */ -+ if (rq->rq_policy != SCHED_FIFO && p != idle) { -+ s64 time_diff = rq->clock - rq->timekeep_clock; -+ -+ niffy_diff(&time_diff, 1); -+ rq->rq_time_slice -= NS_TO_US(time_diff); -+ } -+ -+ rq->rq_last_ran = rq->clock_task; -+ rq->timekeep_clock = rq->clock; -+} -+ -+/* -+ * This is called on context switches. -+ * Bank in p->sched_time the ns elapsed since the last tick or switch. -+ * CPU scheduler quota accounting is also performed here in microseconds. -+ */ -+static void -+update_cpu_clock_switch(struct rq *rq, struct task_struct *p) -+{ -+ long account_ns = rq->clock_task - rq->rq_last_ran; -+ struct task_struct *idle = rq->idle; -+ unsigned long account_pc; -+ -+ if (unlikely(account_ns < 0)) -+ goto ts_account; -+ -+ account_pc = NS_TO_PC(account_ns); -+ -+ /* Accurate subtick timekeeping */ -+ if (p != idle) { -+ pc_user_time(rq, p, account_pc, account_ns); -+ } -+ else -+ pc_idle_time(rq, idle, account_pc); -+ -+ts_account: -+ /* time_slice accounting is done in usecs to avoid overflow on 32bit */ -+ if (rq->rq_policy != SCHED_FIFO && p != idle) { -+ s64 time_diff = rq->clock - rq->timekeep_clock; -+ -+ niffy_diff(&time_diff, 1); -+ rq->rq_time_slice -= NS_TO_US(time_diff); -+ } -+ -+ rq->rq_last_ran = rq->clock_task; -+ rq->timekeep_clock = rq->clock; -+} -+ -+/* -+ * Return any ns on the sched_clock that have not yet been accounted in -+ * @p in case that task is currently running. -+ * -+ * Called with task_grq_lock() held. -+ */ -+static u64 do_task_delta_exec(struct task_struct *p, struct rq *rq) -+{ -+ u64 ns = 0; -+ -+ if (p == rq->curr) { -+ update_clocks(rq); -+ ns = rq->clock_task - rq->rq_last_ran; -+ if (unlikely((s64)ns < 0)) -+ ns = 0; -+ } -+ -+ return ns; -+} -+ -+unsigned long long task_delta_exec(struct task_struct *p) -+{ -+ unsigned long flags; -+ struct rq *rq; -+ u64 ns; -+ -+ rq = task_grq_lock(p, &flags); -+ ns = do_task_delta_exec(p, rq); -+ task_grq_unlock(&flags); -+ -+ return ns; -+} -+ -+/* -+ * Return accounted runtime for the task. -+ * Return separately the current's pending runtime that have not been -+ * accounted yet. -+ * -+ * grq lock already acquired. -+ */ -+unsigned long long task_sched_runtime(struct task_struct *p) -+{ -+ unsigned long flags; -+ struct rq *rq; -+ u64 ns; -+ -+ rq = task_grq_lock(p, &flags); -+ ns = p->sched_time + do_task_delta_exec(p, rq); -+ task_grq_unlock(&flags); -+ -+ return ns; -+} -+ -+/* -+ * Return accounted runtime for the task. -+ * Return separately the current's pending runtime that have not been -+ * accounted yet. -+ */ -+unsigned long long task_sched_runtime_nodelta(struct task_struct *p, unsigned long long *delta) -+{ -+ unsigned long flags; -+ struct rq *rq; -+ u64 ns; -+ -+ rq = task_grq_lock(p, &flags); -+ ns = p->sched_time; -+ *delta = do_task_delta_exec(p, rq); -+ task_grq_unlock(&flags); -+ -+ return ns; -+} -+ -+/* Compatibility crap */ -+void account_user_time(struct task_struct *p, cputime_t cputime, -+ cputime_t cputime_scaled) -+{ -+} -+ -+void account_idle_time(cputime_t cputime) -+{ -+} -+ -+void update_cpu_load_nohz(void) -+{ -+} -+ -+#ifdef CONFIG_NO_HZ_COMMON -+void calc_load_enter_idle(void) -+{ -+} -+ -+void calc_load_exit_idle(void) -+{ -+} -+#endif /* CONFIG_NO_HZ_COMMON */ -+ -+/* -+ * Account guest cpu time to a process. -+ * @p: the process that the cpu time gets accounted to -+ * @cputime: the cpu time spent in virtual machine since the last update -+ * @cputime_scaled: cputime scaled by cpu frequency -+ */ -+static void account_guest_time(struct task_struct *p, cputime_t cputime, -+ cputime_t cputime_scaled) -+{ -+ u64 *cpustat = kcpustat_this_cpu->cpustat; -+ -+ /* Add guest time to process. */ -+ p->utime += (__force u64)cputime; -+ p->utimescaled += (__force u64)cputime_scaled; -+ account_group_user_time(p, cputime); -+ p->gtime += (__force u64)cputime; -+ -+ /* Add guest time to cpustat. */ -+ if (TASK_NICE(p) > 0) { -+ cpustat[CPUTIME_NICE] += (__force u64)cputime; -+ cpustat[CPUTIME_GUEST_NICE] += (__force u64)cputime; -+ } else { -+ cpustat[CPUTIME_USER] += (__force u64)cputime; -+ cpustat[CPUTIME_GUEST] += (__force u64)cputime; -+ } -+} -+ -+/* -+ * Account system cpu time to a process and desired cpustat field -+ * @p: the process that the cpu time gets accounted to -+ * @cputime: the cpu time spent in kernel space since the last update -+ * @cputime_scaled: cputime scaled by cpu frequency -+ * @target_cputime64: pointer to cpustat field that has to be updated -+ */ -+static inline -+void __account_system_time(struct task_struct *p, cputime_t cputime, -+ cputime_t cputime_scaled, cputime64_t *target_cputime64) -+{ -+ /* Add system time to process. */ -+ p->stime += (__force u64)cputime; -+ p->stimescaled += (__force u64)cputime_scaled; -+ account_group_system_time(p, cputime); -+ -+ /* Add system time to cpustat. */ -+ *target_cputime64 += (__force u64)cputime; -+ -+ /* Account for system time used */ -+ acct_update_integrals(p); -+} -+ -+/* -+ * Account system cpu time to a process. -+ * @p: the process that the cpu time gets accounted to -+ * @hardirq_offset: the offset to subtract from hardirq_count() -+ * @cputime: the cpu time spent in kernel space since the last update -+ * @cputime_scaled: cputime scaled by cpu frequency -+ * This is for guest only now. -+ */ -+void account_system_time(struct task_struct *p, int hardirq_offset, -+ cputime_t cputime, cputime_t cputime_scaled) -+{ -+ -+ if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) -+ account_guest_time(p, cputime, cputime_scaled); -+} -+ -+/* -+ * Account for involuntary wait time. -+ * @steal: the cpu time spent in involuntary wait -+ */ -+void account_steal_time(cputime_t cputime) -+{ -+ u64 *cpustat = kcpustat_this_cpu->cpustat; -+ -+ cpustat[CPUTIME_STEAL] += (__force u64)cputime; -+} -+ -+/* -+ * Account for idle time. -+ * @cputime: the cpu time spent in idle wait -+ */ -+static void account_idle_times(cputime_t cputime) -+{ -+ u64 *cpustat = kcpustat_this_cpu->cpustat; -+ struct rq *rq = this_rq(); -+ -+ if (atomic_read(&rq->nr_iowait) > 0) -+ cpustat[CPUTIME_IOWAIT] += (__force u64)cputime; -+ else -+ cpustat[CPUTIME_IDLE] += (__force u64)cputime; -+} -+ -+#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE -+ -+void account_process_tick(struct task_struct *p, int user_tick) -+{ -+} -+ -+/* -+ * Account multiple ticks of steal time. -+ * @p: the process from which the cpu time has been stolen -+ * @ticks: number of stolen ticks -+ */ -+void account_steal_ticks(unsigned long ticks) -+{ -+ account_steal_time(jiffies_to_cputime(ticks)); -+} -+ -+/* -+ * Account multiple ticks of idle time. -+ * @ticks: number of stolen ticks -+ */ -+void account_idle_ticks(unsigned long ticks) -+{ -+ account_idle_times(jiffies_to_cputime(ticks)); -+} -+#endif -+ -+static inline void grq_iso_lock(void) -+ __acquires(grq.iso_lock) -+{ -+ raw_spin_lock(&grq.iso_lock); -+} -+ -+static inline void grq_iso_unlock(void) -+ __releases(grq.iso_lock) -+{ -+ raw_spin_unlock(&grq.iso_lock); -+} -+ -+/* -+ * Functions to test for when SCHED_ISO tasks have used their allocated -+ * quota as real time scheduling and convert them back to SCHED_NORMAL. -+ * Where possible, the data is tested lockless, to avoid grabbing iso_lock -+ * because the occasional inaccurate result won't matter. However the -+ * tick data is only ever modified under lock. iso_refractory is only simply -+ * set to 0 or 1 so it's not worth grabbing the lock yet again for that. -+ */ -+static bool set_iso_refractory(void) -+{ -+ grq.iso_refractory = true; -+ return grq.iso_refractory; -+} -+ -+static bool clear_iso_refractory(void) -+{ -+ grq.iso_refractory = false; -+ return grq.iso_refractory; -+} -+ -+/* -+ * Test if SCHED_ISO tasks have run longer than their alloted period as RT -+ * tasks and set the refractory flag if necessary. There is 10% hysteresis -+ * for unsetting the flag. 115/128 is ~90/100 as a fast shift instead of a -+ * slow division. -+ */ -+static bool test_ret_isorefractory(struct rq *rq) -+{ -+ if (likely(!grq.iso_refractory)) { -+ if (grq.iso_ticks > ISO_PERIOD * sched_iso_cpu) -+ return set_iso_refractory(); -+ } else { -+ if (grq.iso_ticks < ISO_PERIOD * (sched_iso_cpu * 115 / 128)) -+ return clear_iso_refractory(); -+ } -+ return grq.iso_refractory; -+} -+ -+static void iso_tick(void) -+{ -+ grq_iso_lock(); -+ grq.iso_ticks += 100; -+ grq_iso_unlock(); -+} -+ -+/* No SCHED_ISO task was running so decrease rq->iso_ticks */ -+static inline void no_iso_tick(void) -+{ -+ if (grq.iso_ticks) { -+ grq_iso_lock(); -+ grq.iso_ticks -= grq.iso_ticks / ISO_PERIOD + 1; -+ if (unlikely(grq.iso_refractory && grq.iso_ticks < -+ ISO_PERIOD * (sched_iso_cpu * 115 / 128))) -+ clear_iso_refractory(); -+ grq_iso_unlock(); -+ } -+} -+ -+/* This manages tasks that have run out of timeslice during a scheduler_tick */ -+static void task_running_tick(struct rq *rq) -+{ -+ struct task_struct *p; -+ -+ /* -+ * If a SCHED_ISO task is running we increment the iso_ticks. In -+ * order to prevent SCHED_ISO tasks from causing starvation in the -+ * presence of true RT tasks we account those as iso_ticks as well. -+ */ -+ if ((rt_queue(rq) || (iso_queue(rq) && !grq.iso_refractory))) { -+ if (grq.iso_ticks <= (ISO_PERIOD * 128) - 128) -+ iso_tick(); -+ } else -+ no_iso_tick(); -+ -+ if (iso_queue(rq)) { -+ if (unlikely(test_ret_isorefractory(rq))) { -+ if (rq_running_iso(rq)) { -+ /* -+ * SCHED_ISO task is running as RT and limit -+ * has been hit. Force it to reschedule as -+ * SCHED_NORMAL by zeroing its time_slice -+ */ -+ rq->rq_time_slice = 0; -+ } -+ } -+ } -+ -+ /* SCHED_FIFO tasks never run out of timeslice. */ -+ if (rq->rq_policy == SCHED_FIFO) -+ return; -+ /* -+ * Tasks that were scheduled in the first half of a tick are not -+ * allowed to run into the 2nd half of the next tick if they will -+ * run out of time slice in the interim. Otherwise, if they have -+ * less than RESCHED_US μs of time slice left they will be rescheduled. -+ */ -+ if (rq->dither) { -+ if (rq->rq_time_slice > HALF_JIFFY_US) -+ return; -+ else -+ rq->rq_time_slice = 0; -+ } else if (rq->rq_time_slice >= RESCHED_US) -+ return; -+ -+ /* p->time_slice < RESCHED_US. We only modify task_struct under grq lock */ -+ p = rq->curr; -+ grq_lock(); -+ requeue_task(p); -+ set_tsk_need_resched(p); -+ grq_unlock(); -+} -+ -+/* -+ * This function gets called by the timer code, with HZ frequency. -+ * We call it with interrupts disabled. The data modified is all -+ * local to struct rq so we don't need to grab grq lock. -+ */ -+void scheduler_tick(void) -+{ -+ int cpu __maybe_unused = smp_processor_id(); -+ struct rq *rq = cpu_rq(cpu); -+ -+ sched_clock_tick(); -+ /* grq lock not grabbed, so only update rq clock */ -+ update_rq_clock(rq); -+ update_cpu_clock_tick(rq, rq->curr); -+ if (!rq_idle(rq)) -+ task_running_tick(rq); -+ else -+ no_iso_tick(); -+ rq->last_tick = rq->clock; -+ perf_event_task_tick(); -+} -+ -+notrace unsigned long get_parent_ip(unsigned long addr) -+{ -+ if (in_lock_functions(addr)) { -+ addr = CALLER_ADDR2; -+ if (in_lock_functions(addr)) -+ addr = CALLER_ADDR3; -+ } -+ return addr; -+} -+ -+#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \ -+ defined(CONFIG_PREEMPT_TRACER)) -+void __kprobes add_preempt_count(int val) -+{ -+#ifdef CONFIG_DEBUG_PREEMPT -+ /* -+ * Underflow? -+ */ -+ if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0))) -+ return; -+#endif -+ preempt_count() += val; -+#ifdef CONFIG_DEBUG_PREEMPT -+ /* -+ * Spinlock count overflowing soon? -+ */ -+ DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >= -+ PREEMPT_MASK - 10); -+#endif -+ if (preempt_count() == val) -+ trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); -+} -+EXPORT_SYMBOL(add_preempt_count); -+ -+void __kprobes sub_preempt_count(int val) -+{ -+#ifdef CONFIG_DEBUG_PREEMPT -+ /* -+ * Underflow? -+ */ -+ if (DEBUG_LOCKS_WARN_ON(val > preempt_count())) -+ return; -+ /* -+ * Is the spinlock portion underflowing? -+ */ -+ if (DEBUG_LOCKS_WARN_ON((val < PREEMPT_MASK) && -+ !(preempt_count() & PREEMPT_MASK))) -+ return; -+#endif -+ -+ if (preempt_count() == val) -+ trace_preempt_on(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); -+ preempt_count() -= val; -+} -+EXPORT_SYMBOL(sub_preempt_count); -+#endif -+ -+/* -+ * Deadline is "now" in niffies + (offset by priority). Setting the deadline -+ * is the key to everything. It distributes cpu fairly amongst tasks of the -+ * same nice value, it proportions cpu according to nice level, it means the -+ * task that last woke up the longest ago has the earliest deadline, thus -+ * ensuring that interactive tasks get low latency on wake up. The CPU -+ * proportion works out to the square of the virtual deadline difference, so -+ * this equation will give nice 19 3% CPU compared to nice 0. -+ */ -+static inline u64 prio_deadline_diff(int user_prio) -+{ -+ return (prio_ratios[user_prio] * rr_interval * (MS_TO_NS(1) / 128)); -+} -+ -+static inline u64 task_deadline_diff(struct task_struct *p) -+{ -+ return prio_deadline_diff(TASK_USER_PRIO(p)); -+} -+ -+static inline u64 static_deadline_diff(int static_prio) -+{ -+ return prio_deadline_diff(USER_PRIO(static_prio)); -+} -+ -+static inline int longest_deadline_diff(void) -+{ -+ return prio_deadline_diff(39); -+} -+ -+static inline int ms_longest_deadline_diff(void) -+{ -+ return NS_TO_MS(longest_deadline_diff()); -+} -+ -+/* -+ * The time_slice is only refilled when it is empty and that is when we set a -+ * new deadline. -+ */ -+static void time_slice_expired(struct task_struct *p) -+{ -+ p->time_slice = timeslice(); -+ p->deadline = grq.niffies + task_deadline_diff(p); -+} -+ -+/* -+ * Timeslices below RESCHED_US are considered as good as expired as there's no -+ * point rescheduling when there's so little time left. SCHED_BATCH tasks -+ * have been flagged be not latency sensitive and likely to be fully CPU -+ * bound so every time they're rescheduled they have their time_slice -+ * refilled, but get a new later deadline to have little effect on -+ * SCHED_NORMAL tasks. -+ -+ */ -+static inline void check_deadline(struct task_struct *p) -+{ -+ if (p->time_slice < RESCHED_US || batch_task(p)) -+ time_slice_expired(p); -+} -+ -+#define BITOP_WORD(nr) ((nr) / BITS_PER_LONG) -+ -+/* -+ * Scheduler queue bitmap specific find next bit. -+ */ -+static inline unsigned long -+next_sched_bit(const unsigned long *addr, unsigned long offset) -+{ -+ const unsigned long *p; -+ unsigned long result; -+ unsigned long size; -+ unsigned long tmp; -+ -+ size = PRIO_LIMIT; -+ if (offset >= size) -+ return size; -+ -+ p = addr + BITOP_WORD(offset); -+ result = offset & ~(BITS_PER_LONG-1); -+ size -= result; -+ offset %= BITS_PER_LONG; -+ if (offset) { -+ tmp = *(p++); -+ tmp &= (~0UL << offset); -+ if (size < BITS_PER_LONG) -+ goto found_first; -+ if (tmp) -+ goto found_middle; -+ size -= BITS_PER_LONG; -+ result += BITS_PER_LONG; -+ } -+ while (size & ~(BITS_PER_LONG-1)) { -+ if ((tmp = *(p++))) -+ goto found_middle; -+ result += BITS_PER_LONG; -+ size -= BITS_PER_LONG; -+ } -+ if (!size) -+ return result; -+ tmp = *p; -+ -+found_first: -+ tmp &= (~0UL >> (BITS_PER_LONG - size)); -+ if (tmp == 0UL) /* Are any bits set? */ -+ return result + size; /* Nope. */ -+found_middle: -+ return result + __ffs(tmp); -+} -+ -+/* -+ * O(n) lookup of all tasks in the global runqueue. The real brainfuck -+ * of lock contention and O(n). It's not really O(n) as only the queued, -+ * but not running tasks are scanned, and is O(n) queued in the worst case -+ * scenario only because the right task can be found before scanning all of -+ * them. -+ * Tasks are selected in this order: -+ * Real time tasks are selected purely by their static priority and in the -+ * order they were queued, so the lowest value idx, and the first queued task -+ * of that priority value is chosen. -+ * If no real time tasks are found, the SCHED_ISO priority is checked, and -+ * all SCHED_ISO tasks have the same priority value, so they're selected by -+ * the earliest deadline value. -+ * If no SCHED_ISO tasks are found, SCHED_NORMAL tasks are selected by the -+ * earliest deadline. -+ * Finally if no SCHED_NORMAL tasks are found, SCHED_IDLEPRIO tasks are -+ * selected by the earliest deadline. -+ */ -+static inline struct -+task_struct *earliest_deadline_task(struct rq *rq, int cpu, struct task_struct *idle) -+{ -+ struct task_struct *edt = NULL; -+ unsigned long idx = -1; -+ -+ do { -+ struct list_head *queue; -+ struct task_struct *p; -+ u64 earliest_deadline; -+ -+ idx = next_sched_bit(grq.prio_bitmap, ++idx); -+ if (idx >= PRIO_LIMIT) -+ return idle; -+ queue = grq.queue + idx; -+ -+ if (idx < MAX_RT_PRIO) { -+ /* We found an rt task */ -+ list_for_each_entry(p, queue, run_list) { -+ /* Make sure cpu affinity is ok */ -+ if (needs_other_cpu(p, cpu)) -+ continue; -+ edt = p; -+ goto out_take; -+ } -+ /* -+ * None of the RT tasks at this priority can run on -+ * this cpu -+ */ -+ continue; -+ } -+ -+ /* -+ * No rt tasks. Find the earliest deadline task. Now we're in -+ * O(n) territory. -+ */ -+ earliest_deadline = ~0ULL; -+ list_for_each_entry(p, queue, run_list) { -+ u64 dl; -+ -+ /* Make sure cpu affinity is ok */ -+ if (needs_other_cpu(p, cpu)) -+ continue; -+ -+ /* -+ * Soft affinity happens here by not scheduling a task -+ * with its sticky flag set that ran on a different CPU -+ * last when the CPU is scaling, or by greatly biasing -+ * against its deadline when not, based on cpu cache -+ * locality. -+ */ -+ if (task_sticky(p) && task_rq(p) != rq) { -+ if (scaling_rq(rq)) -+ continue; -+ dl = p->deadline << locality_diff(p, rq); -+ } else -+ dl = p->deadline; -+ -+ if (deadline_before(dl, earliest_deadline)) { -+ earliest_deadline = dl; -+ edt = p; -+ } -+ } -+ } while (!edt); -+ -+out_take: -+ take_task(cpu, edt); -+ return edt; -+} -+ -+ -+/* -+ * Print scheduling while atomic bug: -+ */ -+static noinline void __schedule_bug(struct task_struct *prev) -+{ -+ if (oops_in_progress) -+ return; -+ -+ printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n", -+ prev->comm, prev->pid, preempt_count()); -+ -+ debug_show_held_locks(prev); -+ print_modules(); -+ if (irqs_disabled()) -+ print_irqtrace_events(prev); -+ dump_stack(); -+ add_taint(TAINT_WARN, LOCKDEP_STILL_OK); -+} -+ -+/* -+ * Various schedule()-time debugging checks and statistics: -+ */ -+static inline void schedule_debug(struct task_struct *prev) -+{ -+ /* -+ * Test if we are atomic. Since do_exit() needs to call into -+ * schedule() atomically, we ignore that path for now. -+ * Otherwise, whine if we are scheduling when we should not be. -+ */ -+ if (unlikely(in_atomic_preempt_off() && !prev->exit_state)) -+ __schedule_bug(prev); -+ rcu_sleep_check(); -+ -+ profile_hit(SCHED_PROFILING, __builtin_return_address(0)); -+ -+ schedstat_inc(this_rq(), sched_count); -+} -+ -+/* -+ * The currently running task's information is all stored in rq local data -+ * which is only modified by the local CPU, thereby allowing the data to be -+ * changed without grabbing the grq lock. -+ */ -+static inline void set_rq_task(struct rq *rq, struct task_struct *p) -+{ -+ rq->rq_time_slice = p->time_slice; -+ rq->rq_deadline = p->deadline; -+ rq->rq_last_ran = p->last_ran = rq->clock_task; -+ rq->rq_policy = p->policy; -+ rq->rq_prio = p->prio; -+ if (p != rq->idle) -+ rq->rq_running = true; -+ else -+ rq->rq_running = false; -+} -+ -+static void reset_rq_task(struct rq *rq, struct task_struct *p) -+{ -+ rq->rq_policy = p->policy; -+ rq->rq_prio = p->prio; -+} -+ -+/* -+ * schedule() is the main scheduler function. -+ * -+ * The main means of driving the scheduler and thus entering this function are: -+ * -+ * 1. Explicit blocking: mutex, semaphore, waitqueue, etc. -+ * -+ * 2. TIF_NEED_RESCHED flag is checked on interrupt and userspace return -+ * paths. For example, see arch/x86/entry_64.S. -+ * -+ * To drive preemption between tasks, the scheduler sets the flag in timer -+ * interrupt handler scheduler_tick(). -+ * -+ * 3. Wakeups don't really cause entry into schedule(). They add a -+ * task to the run-queue and that's it. -+ * -+ * Now, if the new task added to the run-queue preempts the current -+ * task, then the wakeup sets TIF_NEED_RESCHED and schedule() gets -+ * called on the nearest possible occasion: -+ * -+ * - If the kernel is preemptible (CONFIG_PREEMPT=y): -+ * -+ * - in syscall or exception context, at the next outmost -+ * preempt_enable(). (this might be as soon as the wake_up()'s -+ * spin_unlock()!) -+ * -+ * - in IRQ context, return from interrupt-handler to -+ * preemptible context -+ * -+ * - If the kernel is not preemptible (CONFIG_PREEMPT is not set) -+ * then at the next: -+ * -+ * - cond_resched() call -+ * - explicit schedule() call -+ * - return from syscall or exception to user-space -+ * - return from interrupt-handler to user-space -+ */ -+asmlinkage void __sched schedule(void) -+{ -+ struct task_struct *prev, *next, *idle; -+ unsigned long *switch_count; -+ bool deactivate; -+ struct rq *rq; -+ int cpu; -+ -+need_resched: -+ preempt_disable(); -+ cpu = smp_processor_id(); -+ rq = cpu_rq(cpu); -+ rcu_note_context_switch(cpu); -+ prev = rq->curr; -+ -+ deactivate = false; -+ schedule_debug(prev); -+ -+ grq_lock_irq(); -+ -+ switch_count = &prev->nivcsw; -+ if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) { -+ if (unlikely(signal_pending_state(prev->state, prev))) { -+ prev->state = TASK_RUNNING; -+ } else { -+ deactivate = true; -+ /* -+ * If a worker is going to sleep, notify and -+ * ask workqueue whether it wants to wake up a -+ * task to maintain concurrency. If so, wake -+ * up the task. -+ */ -+ if (prev->flags & PF_WQ_WORKER) { -+ struct task_struct *to_wakeup; -+ -+ to_wakeup = wq_worker_sleeping(prev, cpu); -+ if (to_wakeup) { -+ /* This shouldn't happen, but does */ -+ if (unlikely(to_wakeup == prev)) -+ deactivate = false; -+ else -+ try_to_wake_up_local(to_wakeup); -+ } -+ } -+ } -+ switch_count = &prev->nvcsw; -+ } -+ -+ /* -+ * If we are going to sleep and we have plugged IO queued, make -+ * sure to submit it to avoid deadlocks. -+ */ -+ if (unlikely(deactivate && blk_needs_flush_plug(prev))) { -+ grq_unlock_irq(); -+ preempt_enable_no_resched(); -+ blk_schedule_flush_plug(prev); -+ goto need_resched; -+ } -+ -+ update_clocks(rq); -+ update_cpu_clock_switch(rq, prev); -+ if (rq->clock - rq->last_tick > HALF_JIFFY_NS) -+ rq->dither = false; -+ else -+ rq->dither = true; -+ -+ clear_tsk_need_resched(prev); -+ -+ idle = rq->idle; -+ if (idle != prev) { -+ /* Update all the information stored on struct rq */ -+ prev->time_slice = rq->rq_time_slice; -+ prev->deadline = rq->rq_deadline; -+ check_deadline(prev); -+ prev->last_ran = rq->clock_task; -+ -+ /* Task changed affinity off this CPU */ -+ if (needs_other_cpu(prev, cpu)) { -+ if (!deactivate) -+ resched_suitable_idle(prev); -+ } else if (!deactivate) { -+ if (!queued_notrunning()) { -+ /* -+ * We now know prev is the only thing that is -+ * awaiting CPU so we can bypass rechecking for -+ * the earliest deadline task and just run it -+ * again. -+ */ -+ set_rq_task(rq, prev); -+ grq_unlock_irq(); -+ goto rerun_prev_unlocked; -+ } else -+ swap_sticky(rq, cpu, prev); -+ } -+ return_task(prev, deactivate); -+ } -+ -+ if (unlikely(!queued_notrunning())) { -+ /* -+ * This CPU is now truly idle as opposed to when idle is -+ * scheduled as a high priority task in its own right. -+ */ -+ next = idle; -+ schedstat_inc(rq, sched_goidle); -+ set_cpuidle_map(cpu); -+ } else { -+ next = earliest_deadline_task(rq, cpu, idle); -+ if (likely(next->prio != PRIO_LIMIT)) -+ clear_cpuidle_map(cpu); -+ else -+ set_cpuidle_map(cpu); -+ } -+ -+ if (likely(prev != next)) { -+ resched_suitable_idle(prev); -+ /* -+ * Don't stick tasks when a real time task is going to run as -+ * they may literally get stuck. -+ */ -+ if (rt_task(next)) -+ unstick_task(rq, prev); -+ set_rq_task(rq, next); -+ grq.nr_switches++; -+ prev->on_cpu = false; -+ next->on_cpu = true; -+ rq->curr = next; -+ ++*switch_count; -+ -+ context_switch(rq, prev, next); /* unlocks the grq */ -+ /* -+ * The context switch have flipped the stack from under us -+ * and restored the local variables which were saved when -+ * this task called schedule() in the past. prev == current -+ * is still correct, but it can be moved to another cpu/rq. -+ */ -+ cpu = smp_processor_id(); -+ rq = cpu_rq(cpu); -+ idle = rq->idle; -+ } else -+ grq_unlock_irq(); -+ -+rerun_prev_unlocked: -+ sched_preempt_enable_no_resched(); -+ if (unlikely(need_resched())) -+ goto need_resched; -+} -+EXPORT_SYMBOL(schedule); -+ -+#ifdef CONFIG_RCU_USER_QS -+asmlinkage void __sched schedule_user(void) -+{ -+ /* -+ * If we come here after a random call to set_need_resched(), -+ * or we have been woken up remotely but the IPI has not yet arrived, -+ * we haven't yet exited the RCU idle mode. Do it here manually until -+ * we find a better solution. -+ */ -+ user_exit(); -+ schedule(); -+ user_enter(); -+} -+#endif -+ -+/** -+ * schedule_preempt_disabled - called with preemption disabled -+ * -+ * Returns with preemption disabled. Note: preempt_count must be 1 -+ */ -+void __sched schedule_preempt_disabled(void) -+{ -+ sched_preempt_enable_no_resched(); -+ schedule(); -+ preempt_disable(); -+} -+ -+#ifdef CONFIG_PREEMPT -+/* -+ * this is the entry point to schedule() from in-kernel preemption -+ * off of preempt_enable. Kernel preemptions off return from interrupt -+ * occur there and call schedule directly. -+ */ -+asmlinkage void __sched notrace preempt_schedule(void) -+{ -+ struct thread_info *ti = current_thread_info(); -+ -+ /* -+ * If there is a non-zero preempt_count or interrupts are disabled, -+ * we do not want to preempt the current task. Just return.. -+ */ -+ if (likely(ti->preempt_count || irqs_disabled())) -+ return; -+ -+ do { -+ add_preempt_count_notrace(PREEMPT_ACTIVE); -+ schedule(); -+ sub_preempt_count_notrace(PREEMPT_ACTIVE); -+ -+ /* -+ * Check again in case we missed a preemption opportunity -+ * between schedule and now. -+ */ -+ barrier(); -+ } while (need_resched()); -+} -+EXPORT_SYMBOL(preempt_schedule); -+ -+/* -+ * this is the entry point to schedule() from kernel preemption -+ * off of irq context. -+ * Note, that this is called and return with irqs disabled. This will -+ * protect us against recursive calling from irq. -+ */ -+asmlinkage void __sched preempt_schedule_irq(void) -+{ -+ struct thread_info *ti = current_thread_info(); -+ enum ctx_state prev_state; -+ -+ /* Catch callers which need to be fixed */ -+ BUG_ON(ti->preempt_count || !irqs_disabled()); -+ -+ prev_state = exception_enter(); -+ -+ do { -+ add_preempt_count(PREEMPT_ACTIVE); -+ local_irq_enable(); -+ schedule(); -+ local_irq_disable(); -+ sub_preempt_count(PREEMPT_ACTIVE); -+ -+ /* -+ * Check again in case we missed a preemption opportunity -+ * between schedule and now. -+ */ -+ barrier(); -+ } while (need_resched()); -+ -+ exception_exit(prev_state); -+} -+ -+#endif /* CONFIG_PREEMPT */ -+ -+int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags, -+ void *key) -+{ -+ return try_to_wake_up(curr->private, mode, wake_flags); -+} -+EXPORT_SYMBOL(default_wake_function); -+ -+/* -+ * The core wakeup function. Non-exclusive wakeups (nr_exclusive == 0) just -+ * wake everything up. If it's an exclusive wakeup (nr_exclusive == small +ve -+ * number) then we wake all the non-exclusive tasks and one exclusive task. -+ * -+ * There are circumstances in which we can try to wake a task which has already -+ * started to run but is not in state TASK_RUNNING. try_to_wake_up() returns -+ * zero in this (rare) case, and we handle it by continuing to scan the queue. -+ */ -+static void __wake_up_common(wait_queue_head_t *q, unsigned int mode, -+ int nr_exclusive, int wake_flags, void *key) -+{ -+ struct list_head *tmp, *next; -+ -+ list_for_each_safe(tmp, next, &q->task_list) { -+ wait_queue_t *curr = list_entry(tmp, wait_queue_t, task_list); -+ unsigned int flags = curr->flags; -+ -+ if (curr->func(curr, mode, wake_flags, key) && -+ (flags & WQ_FLAG_EXCLUSIVE) && !--nr_exclusive) -+ break; -+ } -+} -+ -+/** -+ * __wake_up - wake up threads blocked on a waitqueue. -+ * @q: the waitqueue -+ * @mode: which threads -+ * @nr_exclusive: how many wake-one or wake-many threads to wake up -+ * @key: is directly passed to the wakeup function -+ * -+ * It may be assumed that this function implies a write memory barrier before -+ * changing the task state if and only if any tasks are woken up. -+ */ -+void __wake_up(wait_queue_head_t *q, unsigned int mode, -+ int nr_exclusive, void *key) -+{ -+ unsigned long flags; -+ -+ spin_lock_irqsave(&q->lock, flags); -+ __wake_up_common(q, mode, nr_exclusive, 0, key); -+ spin_unlock_irqrestore(&q->lock, flags); -+} -+EXPORT_SYMBOL(__wake_up); -+ -+/* -+ * Same as __wake_up but called with the spinlock in wait_queue_head_t held. -+ */ -+void __wake_up_locked(wait_queue_head_t *q, unsigned int mode, int nr) -+{ -+ __wake_up_common(q, mode, nr, 0, NULL); -+} -+EXPORT_SYMBOL_GPL(__wake_up_locked); -+ -+void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key) -+{ -+ __wake_up_common(q, mode, 1, 0, key); -+} -+EXPORT_SYMBOL_GPL(__wake_up_locked_key); -+ -+/** -+ * __wake_up_sync_key - wake up threads blocked on a waitqueue. -+ * @q: the waitqueue -+ * @mode: which threads -+ * @nr_exclusive: how many wake-one or wake-many threads to wake up -+ * @key: opaque value to be passed to wakeup targets -+ * -+ * The sync wakeup differs that the waker knows that it will schedule -+ * away soon, so while the target thread will be woken up, it will not -+ * be migrated to another CPU - ie. the two threads are 'synchronised' -+ * with each other. This can prevent needless bouncing between CPUs. -+ * -+ * On UP it can prevent extra preemption. -+ * -+ * It may be assumed that this function implies a write memory barrier before -+ * changing the task state if and only if any tasks are woken up. -+ */ -+void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, -+ int nr_exclusive, void *key) -+{ -+ unsigned long flags; -+ int wake_flags = WF_SYNC; -+ -+ if (unlikely(!q)) -+ return; -+ -+ if (unlikely(!nr_exclusive)) -+ wake_flags = 0; -+ -+ spin_lock_irqsave(&q->lock, flags); -+ __wake_up_common(q, mode, nr_exclusive, wake_flags, key); -+ spin_unlock_irqrestore(&q->lock, flags); -+} -+EXPORT_SYMBOL_GPL(__wake_up_sync_key); -+ -+/** -+ * __wake_up_sync - wake up threads blocked on a waitqueue. -+ * @q: the waitqueue -+ * @mode: which threads -+ * @nr_exclusive: how many wake-one or wake-many threads to wake up -+ * -+ * The sync wakeup differs that the waker knows that it will schedule -+ * away soon, so while the target thread will be woken up, it will not -+ * be migrated to another CPU - ie. the two threads are 'synchronised' -+ * with each other. This can prevent needless bouncing between CPUs. -+ * -+ * On UP it can prevent extra preemption. -+ */ -+void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr_exclusive) -+{ -+ unsigned long flags; -+ int sync = 1; -+ -+ if (unlikely(!q)) -+ return; -+ -+ if (unlikely(!nr_exclusive)) -+ sync = 0; -+ -+ spin_lock_irqsave(&q->lock, flags); -+ __wake_up_common(q, mode, nr_exclusive, sync, NULL); -+ spin_unlock_irqrestore(&q->lock, flags); -+} -+EXPORT_SYMBOL_GPL(__wake_up_sync); /* For internal use only */ -+ -+/** -+ * complete: - signals a single thread waiting on this completion -+ * @x: holds the state of this particular completion -+ * -+ * This will wake up a single thread waiting on this completion. Threads will be -+ * awakened in the same order in which they were queued. -+ * -+ * See also complete_all(), wait_for_completion() and related routines. -+ * -+ * It may be assumed that this function implies a write memory barrier before -+ * changing the task state if and only if any tasks are woken up. -+ */ -+void complete(struct completion *x) -+{ -+ unsigned long flags; -+ -+ spin_lock_irqsave(&x->wait.lock, flags); -+ x->done++; -+ __wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL); -+ spin_unlock_irqrestore(&x->wait.lock, flags); -+} -+EXPORT_SYMBOL(complete); -+ -+/** -+ * complete_all: - signals all threads waiting on this completion -+ * @x: holds the state of this particular completion -+ * -+ * This will wake up all threads waiting on this particular completion event. -+ * -+ * It may be assumed that this function implies a write memory barrier before -+ * changing the task state if and only if any tasks are woken up. -+ */ -+void complete_all(struct completion *x) -+{ -+ unsigned long flags; -+ -+ spin_lock_irqsave(&x->wait.lock, flags); -+ x->done += UINT_MAX/2; -+ __wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL); -+ spin_unlock_irqrestore(&x->wait.lock, flags); -+} -+EXPORT_SYMBOL(complete_all); -+ -+static inline long __sched -+do_wait_for_common(struct completion *x, -+ long (*action)(long), long timeout, int state) -+{ -+ if (!x->done) { -+ DECLARE_WAITQUEUE(wait, current); -+ -+ __add_wait_queue_tail_exclusive(&x->wait, &wait); -+ do { -+ if (signal_pending_state(state, current)) { -+ timeout = -ERESTARTSYS; -+ break; -+ } -+ __set_current_state(state); -+ spin_unlock_irq(&x->wait.lock); -+ timeout = action(timeout); -+ spin_lock_irq(&x->wait.lock); -+ } while (!x->done && timeout); -+ __remove_wait_queue(&x->wait, &wait); -+ if (!x->done) -+ return timeout; -+ } -+ x->done--; -+ return timeout ?: 1; -+} -+ -+static inline long __sched -+__wait_for_common(struct completion *x, -+ long (*action)(long), long timeout, int state) -+{ -+ might_sleep(); -+ -+ spin_lock_irq(&x->wait.lock); -+ timeout = do_wait_for_common(x, action, timeout, state); -+ spin_unlock_irq(&x->wait.lock); -+ return timeout; -+} -+ -+static long __sched -+wait_for_common(struct completion *x, long timeout, int state) -+{ -+ return __wait_for_common(x, schedule_timeout, timeout, state); -+} -+ -+static long __sched -+wait_for_common_io(struct completion *x, long timeout, int state) -+{ -+ return __wait_for_common(x, io_schedule_timeout, timeout, state); -+} -+ -+/** -+ * wait_for_completion: - waits for completion of a task -+ * @x: holds the state of this particular completion -+ * -+ * This waits to be signaled for completion of a specific task. It is NOT -+ * interruptible and there is no timeout. -+ * -+ * See also similar routines (i.e. wait_for_completion_timeout()) with timeout -+ * and interrupt capability. Also see complete(). -+ */ -+void __sched wait_for_completion(struct completion *x) -+{ -+ wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE); -+} -+EXPORT_SYMBOL(wait_for_completion); -+ -+/** -+ * wait_for_completion_timeout: - waits for completion of a task (w/timeout) -+ * @x: holds the state of this particular completion -+ * @timeout: timeout value in jiffies -+ * -+ * This waits for either a completion of a specific task to be signaled or for a -+ * specified timeout to expire. The timeout is in jiffies. It is not -+ * interruptible. -+ * -+ * The return value is 0 if timed out, and positive (at least 1, or number of -+ * jiffies left till timeout) if completed. -+ */ -+unsigned long __sched -+wait_for_completion_timeout(struct completion *x, unsigned long timeout) -+{ -+ return wait_for_common(x, timeout, TASK_UNINTERRUPTIBLE); -+} -+EXPORT_SYMBOL(wait_for_completion_timeout); -+ -+ /** -+ * wait_for_completion_io: - waits for completion of a task -+ * @x: holds the state of this particular completion -+ * -+ * This waits to be signaled for completion of a specific task. It is NOT -+ * interruptible and there is no timeout. The caller is accounted as waiting -+ * for IO. -+ */ -+void __sched wait_for_completion_io(struct completion *x) -+{ -+ wait_for_common_io(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE); -+} -+EXPORT_SYMBOL(wait_for_completion_io); -+ -+/** -+ * wait_for_completion_io_timeout: - waits for completion of a task (w/timeout) -+ * @x: holds the state of this particular completion -+ * @timeout: timeout value in jiffies -+ * -+ * This waits for either a completion of a specific task to be signaled or for a -+ * specified timeout to expire. The timeout is in jiffies. It is not -+ * interruptible. The caller is accounted as waiting for IO. -+ * -+ * The return value is 0 if timed out, and positive (at least 1, or number of -+ * jiffies left till timeout) if completed. -+ */ -+unsigned long __sched -+wait_for_completion_io_timeout(struct completion *x, unsigned long timeout) -+{ -+ return wait_for_common_io(x, timeout, TASK_UNINTERRUPTIBLE); -+} -+EXPORT_SYMBOL(wait_for_completion_io_timeout); -+ -+/** -+ * wait_for_completion_interruptible: - waits for completion of a task (w/intr) -+ * @x: holds the state of this particular completion -+ * -+ * This waits for completion of a specific task to be signaled. It is -+ * interruptible. -+ * -+ * The return value is -ERESTARTSYS if interrupted, 0 if completed. -+ */ -+int __sched wait_for_completion_interruptible(struct completion *x) -+{ -+ long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_INTERRUPTIBLE); -+ if (t == -ERESTARTSYS) -+ return t; -+ return 0; -+} -+EXPORT_SYMBOL(wait_for_completion_interruptible); -+ -+/** -+ * wait_for_completion_interruptible_timeout: - waits for completion (w/(to,intr)) -+ * @x: holds the state of this particular completion -+ * @timeout: timeout value in jiffies -+ * -+ * This waits for either a completion of a specific task to be signaled or for a -+ * specified timeout to expire. It is interruptible. The timeout is in jiffies. -+ * -+ * The return value is -ERESTARTSYS if interrupted, 0 if timed out, -+ * positive (at least 1, or number of jiffies left till timeout) if completed. -+ */ -+long __sched -+wait_for_completion_interruptible_timeout(struct completion *x, -+ unsigned long timeout) -+{ -+ return wait_for_common(x, timeout, TASK_INTERRUPTIBLE); -+} -+EXPORT_SYMBOL(wait_for_completion_interruptible_timeout); -+ -+/** -+ * wait_for_completion_killable: - waits for completion of a task (killable) -+ * @x: holds the state of this particular completion -+ * -+ * This waits to be signaled for completion of a specific task. It can be -+ * interrupted by a kill signal. -+ * -+ * The return value is -ERESTARTSYS if interrupted, 0 if timed out, -+ * positive (at least 1, or number of jiffies left till timeout) if completed. -+ */ -+int __sched wait_for_completion_killable(struct completion *x) -+{ -+ long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_KILLABLE); -+ if (t == -ERESTARTSYS) -+ return t; -+ return 0; -+} -+EXPORT_SYMBOL(wait_for_completion_killable); -+ -+/** -+ * wait_for_completion_killable_timeout: - waits for completion of a task (w/(to,killable)) -+ * @x: holds the state of this particular completion -+ * @timeout: timeout value in jiffies -+ * -+ * This waits for either a completion of a specific task to be -+ * signaled or for a specified timeout to expire. It can be -+ * interrupted by a kill signal. The timeout is in jiffies. -+ */ -+long __sched -+wait_for_completion_killable_timeout(struct completion *x, -+ unsigned long timeout) -+{ -+ return wait_for_common(x, timeout, TASK_KILLABLE); -+} -+EXPORT_SYMBOL(wait_for_completion_killable_timeout); -+ -+/** -+ * try_wait_for_completion - try to decrement a completion without blocking -+ * @x: completion structure -+ * -+ * Returns: 0 if a decrement cannot be done without blocking -+ * 1 if a decrement succeeded. -+ * -+ * If a completion is being used as a counting completion, -+ * attempt to decrement the counter without blocking. This -+ * enables us to avoid waiting if the resource the completion -+ * is protecting is not available. -+ */ -+bool try_wait_for_completion(struct completion *x) -+{ -+ unsigned long flags; -+ int ret = 1; -+ -+ spin_lock_irqsave(&x->wait.lock, flags); -+ if (!x->done) -+ ret = 0; -+ else -+ x->done--; -+ spin_unlock_irqrestore(&x->wait.lock, flags); -+ return ret; -+} -+EXPORT_SYMBOL(try_wait_for_completion); -+ -+/** -+ * completion_done - Test to see if a completion has any waiters -+ * @x: completion structure -+ * -+ * Returns: 0 if there are waiters (wait_for_completion() in progress) -+ * 1 if there are no waiters. -+ * -+ */ -+bool completion_done(struct completion *x) -+{ -+ unsigned long flags; -+ int ret = 1; -+ -+ spin_lock_irqsave(&x->wait.lock, flags); -+ if (!x->done) -+ ret = 0; -+ spin_unlock_irqrestore(&x->wait.lock, flags); -+ return ret; -+} -+EXPORT_SYMBOL(completion_done); -+ -+static long __sched -+sleep_on_common(wait_queue_head_t *q, int state, long timeout) -+{ -+ unsigned long flags; -+ wait_queue_t wait; -+ -+ init_waitqueue_entry(&wait, current); -+ -+ __set_current_state(state); -+ -+ spin_lock_irqsave(&q->lock, flags); -+ __add_wait_queue(q, &wait); -+ spin_unlock(&q->lock); -+ timeout = schedule_timeout(timeout); -+ spin_lock_irq(&q->lock); -+ __remove_wait_queue(q, &wait); -+ spin_unlock_irqrestore(&q->lock, flags); -+ -+ return timeout; -+} -+ -+void __sched interruptible_sleep_on(wait_queue_head_t *q) -+{ -+ sleep_on_common(q, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); -+} -+EXPORT_SYMBOL(interruptible_sleep_on); -+ -+long __sched -+interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout) -+{ -+ return sleep_on_common(q, TASK_INTERRUPTIBLE, timeout); -+} -+EXPORT_SYMBOL(interruptible_sleep_on_timeout); -+ -+void __sched sleep_on(wait_queue_head_t *q) -+{ -+ sleep_on_common(q, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); -+} -+EXPORT_SYMBOL(sleep_on); -+ -+long __sched sleep_on_timeout(wait_queue_head_t *q, long timeout) -+{ -+ return sleep_on_common(q, TASK_UNINTERRUPTIBLE, timeout); -+} -+EXPORT_SYMBOL(sleep_on_timeout); -+ -+#ifdef CONFIG_RT_MUTEXES -+ -+/* -+ * rt_mutex_setprio - set the current priority of a task -+ * @p: task -+ * @prio: prio value (kernel-internal form) -+ * -+ * This function changes the 'effective' priority of a task. It does -+ * not touch ->normal_prio like __setscheduler(). -+ * -+ * Used by the rt_mutex code to implement priority inheritance logic. -+ */ -+void rt_mutex_setprio(struct task_struct *p, int prio) -+{ -+ unsigned long flags; -+ int queued, oldprio; -+ struct rq *rq; -+ -+ BUG_ON(prio < 0 || prio > MAX_PRIO); -+ -+ rq = task_grq_lock(p, &flags); -+ -+ /* -+ * Idle task boosting is a nono in general. There is one -+ * exception, when PREEMPT_RT and NOHZ is active: -+ * -+ * The idle task calls get_next_timer_interrupt() and holds -+ * the timer wheel base->lock on the CPU and another CPU wants -+ * to access the timer (probably to cancel it). We can safely -+ * ignore the boosting request, as the idle CPU runs this code -+ * with interrupts disabled and will complete the lock -+ * protected section without being interrupted. So there is no -+ * real need to boost. -+ */ -+ if (unlikely(p == rq->idle)) { -+ WARN_ON(p != rq->curr); -+ WARN_ON(p->pi_blocked_on); -+ goto out_unlock; -+ } -+ -+ trace_sched_pi_setprio(p, prio); -+ oldprio = p->prio; -+ queued = task_queued(p); -+ if (queued) -+ dequeue_task(p); -+ p->prio = prio; -+ if (task_running(p) && prio > oldprio) -+ resched_task(p); -+ if (queued) { -+ enqueue_task(p); -+ try_preempt(p, rq); -+ } -+ -+out_unlock: -+ task_grq_unlock(&flags); -+} -+ -+#endif -+ -+/* -+ * Adjust the deadline for when the priority is to change, before it's -+ * changed. -+ */ -+static inline void adjust_deadline(struct task_struct *p, int new_prio) -+{ -+ p->deadline += static_deadline_diff(new_prio) - task_deadline_diff(p); -+} -+ -+void set_user_nice(struct task_struct *p, long nice) -+{ -+ int queued, new_static, old_static; -+ unsigned long flags; -+ struct rq *rq; -+ -+ if (TASK_NICE(p) == nice || nice < -20 || nice > 19) -+ return; -+ new_static = NICE_TO_PRIO(nice); -+ /* -+ * We have to be careful, if called from sys_setpriority(), -+ * the task might be in the middle of scheduling on another CPU. -+ */ -+ rq = time_task_grq_lock(p, &flags); -+ /* -+ * The RT priorities are set via sched_setscheduler(), but we still -+ * allow the 'normal' nice value to be set - but as expected -+ * it wont have any effect on scheduling until the task is -+ * not SCHED_NORMAL/SCHED_BATCH: -+ */ -+ if (has_rt_policy(p)) { -+ p->static_prio = new_static; -+ goto out_unlock; -+ } -+ queued = task_queued(p); -+ if (queued) -+ dequeue_task(p); -+ -+ adjust_deadline(p, new_static); -+ old_static = p->static_prio; -+ p->static_prio = new_static; -+ p->prio = effective_prio(p); -+ -+ if (queued) { -+ enqueue_task(p); -+ if (new_static < old_static) -+ try_preempt(p, rq); -+ } else if (task_running(p)) { -+ reset_rq_task(rq, p); -+ if (old_static < new_static) -+ resched_task(p); -+ } -+out_unlock: -+ task_grq_unlock(&flags); -+} -+EXPORT_SYMBOL(set_user_nice); -+ -+/* -+ * can_nice - check if a task can reduce its nice value -+ * @p: task -+ * @nice: nice value -+ */ -+int can_nice(const struct task_struct *p, const int nice) -+{ -+ /* convert nice value [19,-20] to rlimit style value [1,40] */ -+ int nice_rlim = 20 - nice; -+ -+ return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) || -+ capable(CAP_SYS_NICE)); -+} -+ -+#ifdef __ARCH_WANT_SYS_NICE -+ -+/* -+ * sys_nice - change the priority of the current process. -+ * @increment: priority increment -+ * -+ * sys_setpriority is a more generic, but much slower function that -+ * does similar things. -+ */ -+SYSCALL_DEFINE1(nice, int, increment) -+{ -+ long nice, retval; -+ -+ /* -+ * Setpriority might change our priority at the same moment. -+ * We don't have to worry. Conceptually one call occurs first -+ * and we have a single winner. -+ */ -+ if (increment < -40) -+ increment = -40; -+ if (increment > 40) -+ increment = 40; -+ -+ nice = TASK_NICE(current) + increment; -+ if (nice < -20) -+ nice = -20; -+ if (nice > 19) -+ nice = 19; -+ -+ if (increment < 0 && !can_nice(current, nice)) -+ return -EPERM; -+ -+ retval = security_task_setnice(current, nice); -+ if (retval) -+ return retval; -+ -+ set_user_nice(current, nice); -+ return 0; -+} -+ -+#endif -+ -+/** -+ * task_prio - return the priority value of a given task. -+ * @p: the task in question. -+ * -+ * This is the priority value as seen by users in /proc. -+ * RT tasks are offset by -100. Normal tasks are centered around 1, value goes -+ * from 0 (SCHED_ISO) up to 82 (nice +19 SCHED_IDLEPRIO). -+ */ -+int task_prio(const struct task_struct *p) -+{ -+ int delta, prio = p->prio - MAX_RT_PRIO; -+ -+ /* rt tasks and iso tasks */ -+ if (prio <= 0) -+ goto out; -+ -+ /* Convert to ms to avoid overflows */ -+ delta = NS_TO_MS(p->deadline - grq.niffies); -+ delta = delta * 40 / ms_longest_deadline_diff(); -+ if (delta > 0 && delta <= 80) -+ prio += delta; -+ if (idleprio_task(p)) -+ prio += 40; -+out: -+ return prio; -+} -+ -+/** -+ * task_nice - return the nice value of a given task. -+ * @p: the task in question. -+ */ -+int task_nice(const struct task_struct *p) -+{ -+ return TASK_NICE(p); -+} -+EXPORT_SYMBOL_GPL(task_nice); -+ -+/** -+ * idle_cpu - is a given cpu idle currently? -+ * @cpu: the processor in question. -+ */ -+int idle_cpu(int cpu) -+{ -+ return cpu_curr(cpu) == cpu_rq(cpu)->idle; -+} -+ -+/** -+ * idle_task - return the idle task for a given cpu. -+ * @cpu: the processor in question. -+ */ -+struct task_struct *idle_task(int cpu) -+{ -+ return cpu_rq(cpu)->idle; -+} -+ -+/** -+ * find_process_by_pid - find a process with a matching PID value. -+ * @pid: the pid in question. -+ */ -+static inline struct task_struct *find_process_by_pid(pid_t pid) -+{ -+ return pid ? find_task_by_vpid(pid) : current; -+} -+ -+/* Actually do priority change: must hold grq lock. */ -+static void -+__setscheduler(struct task_struct *p, struct rq *rq, int policy, int prio) -+{ -+ int oldrtprio, oldprio; -+ -+ p->policy = policy; -+ oldrtprio = p->rt_priority; -+ p->rt_priority = prio; -+ p->normal_prio = normal_prio(p); -+ oldprio = p->prio; -+ /* we are holding p->pi_lock already */ -+ p->prio = rt_mutex_getprio(p); -+ if (task_running(p)) { -+ reset_rq_task(rq, p); -+ /* Resched only if we might now be preempted */ -+ if (p->prio > oldprio || p->rt_priority > oldrtprio) -+ resched_task(p); -+ } -+} -+ -+/* -+ * check the target process has a UID that matches the current process's -+ */ -+static bool check_same_owner(struct task_struct *p) -+{ -+ const struct cred *cred = current_cred(), *pcred; -+ bool match; -+ -+ rcu_read_lock(); -+ pcred = __task_cred(p); -+ match = (uid_eq(cred->euid, pcred->euid) || -+ uid_eq(cred->euid, pcred->uid)); -+ rcu_read_unlock(); -+ return match; -+} -+ -+static int __sched_setscheduler(struct task_struct *p, int policy, -+ const struct sched_param *param, bool user) -+{ -+ struct sched_param zero_param = { .sched_priority = 0 }; -+ int queued, retval, oldpolicy = -1; -+ unsigned long flags, rlim_rtprio = 0; -+ int reset_on_fork; -+ struct rq *rq; -+ -+ /* may grab non-irq protected spin_locks */ -+ BUG_ON(in_interrupt()); -+ -+ if (is_rt_policy(policy) && !capable(CAP_SYS_NICE)) { -+ unsigned long lflags; -+ -+ if (!lock_task_sighand(p, &lflags)) -+ return -ESRCH; -+ rlim_rtprio = task_rlimit(p, RLIMIT_RTPRIO); -+ unlock_task_sighand(p, &lflags); -+ if (rlim_rtprio) -+ goto recheck; -+ /* -+ * If the caller requested an RT policy without having the -+ * necessary rights, we downgrade the policy to SCHED_ISO. -+ * We also set the parameter to zero to pass the checks. -+ */ -+ policy = SCHED_ISO; -+ param = &zero_param; -+ } -+recheck: -+ /* double check policy once rq lock held */ -+ if (policy < 0) { -+ reset_on_fork = p->sched_reset_on_fork; -+ policy = oldpolicy = p->policy; -+ } else { -+ reset_on_fork = !!(policy & SCHED_RESET_ON_FORK); -+ policy &= ~SCHED_RESET_ON_FORK; -+ -+ if (!SCHED_RANGE(policy)) -+ return -EINVAL; -+ } -+ -+ /* -+ * Valid priorities for SCHED_FIFO and SCHED_RR are -+ * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL and -+ * SCHED_BATCH is 0. -+ */ -+ if (param->sched_priority < 0 || -+ (p->mm && param->sched_priority > MAX_USER_RT_PRIO - 1) || -+ (!p->mm && param->sched_priority > MAX_RT_PRIO - 1)) -+ return -EINVAL; -+ if (is_rt_policy(policy) != (param->sched_priority != 0)) -+ return -EINVAL; -+ -+ /* -+ * Allow unprivileged RT tasks to decrease priority: -+ */ -+ if (user && !capable(CAP_SYS_NICE)) { -+ if (is_rt_policy(policy)) { -+ unsigned long rlim_rtprio = -+ task_rlimit(p, RLIMIT_RTPRIO); -+ -+ /* can't set/change the rt policy */ -+ if (policy != p->policy && !rlim_rtprio) -+ return -EPERM; -+ -+ /* can't increase priority */ -+ if (param->sched_priority > p->rt_priority && -+ param->sched_priority > rlim_rtprio) -+ return -EPERM; -+ } else { -+ switch (p->policy) { -+ /* -+ * Can only downgrade policies but not back to -+ * SCHED_NORMAL -+ */ -+ case SCHED_ISO: -+ if (policy == SCHED_ISO) -+ goto out; -+ if (policy == SCHED_NORMAL) -+ return -EPERM; -+ break; -+ case SCHED_BATCH: -+ if (policy == SCHED_BATCH) -+ goto out; -+ if (policy != SCHED_IDLEPRIO) -+ return -EPERM; -+ break; -+ case SCHED_IDLEPRIO: -+ if (policy == SCHED_IDLEPRIO) -+ goto out; -+ return -EPERM; -+ default: -+ break; -+ } -+ } -+ -+ /* can't change other user's priorities */ -+ if (!check_same_owner(p)) -+ return -EPERM; -+ -+ /* Normal users shall not reset the sched_reset_on_fork flag */ -+ if (p->sched_reset_on_fork && !reset_on_fork) -+ return -EPERM; -+ } -+ -+ if (user) { -+ retval = security_task_setscheduler(p); -+ if (retval) -+ return retval; -+ } -+ -+ /* -+ * make sure no PI-waiters arrive (or leave) while we are -+ * changing the priority of the task: -+ */ -+ raw_spin_lock_irqsave(&p->pi_lock, flags); -+ /* -+ * To be able to change p->policy safely, the grunqueue lock must be -+ * held. -+ */ -+ rq = __task_grq_lock(p); -+ -+ /* -+ * Changing the policy of the stop threads its a very bad idea -+ */ -+ if (p == rq->stop) { -+ __task_grq_unlock(); -+ raw_spin_unlock_irqrestore(&p->pi_lock, flags); -+ return -EINVAL; -+ } -+ -+ /* -+ * If not changing anything there's no need to proceed further: -+ */ -+ if (unlikely(policy == p->policy && (!is_rt_policy(policy) || -+ param->sched_priority == p->rt_priority))) { -+ -+ __task_grq_unlock(); -+ raw_spin_unlock_irqrestore(&p->pi_lock, flags); -+ return 0; -+ } -+ -+ /* recheck policy now with rq lock held */ -+ if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) { -+ policy = oldpolicy = -1; -+ __task_grq_unlock(); -+ raw_spin_unlock_irqrestore(&p->pi_lock, flags); -+ goto recheck; -+ } -+ update_clocks(rq); -+ p->sched_reset_on_fork = reset_on_fork; -+ -+ queued = task_queued(p); -+ if (queued) -+ dequeue_task(p); -+ __setscheduler(p, rq, policy, param->sched_priority); -+ if (queued) { -+ enqueue_task(p); -+ try_preempt(p, rq); -+ } -+ __task_grq_unlock(); -+ raw_spin_unlock_irqrestore(&p->pi_lock, flags); -+ -+ rt_mutex_adjust_pi(p); -+out: -+ return 0; -+} -+ -+/** -+ * sched_setscheduler - change the scheduling policy and/or RT priority of a thread. -+ * @p: the task in question. -+ * @policy: new policy. -+ * @param: structure containing the new RT priority. -+ * -+ * NOTE that the task may be already dead. -+ */ -+int sched_setscheduler(struct task_struct *p, int policy, -+ const struct sched_param *param) -+{ -+ return __sched_setscheduler(p, policy, param, true); -+} -+ -+EXPORT_SYMBOL_GPL(sched_setscheduler); -+ -+/** -+ * sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace. -+ * @p: the task in question. -+ * @policy: new policy. -+ * @param: structure containing the new RT priority. -+ * -+ * Just like sched_setscheduler, only don't bother checking if the -+ * current context has permission. For example, this is needed in -+ * stop_machine(): we create temporary high priority worker threads, -+ * but our caller might not have that capability. -+ */ -+int sched_setscheduler_nocheck(struct task_struct *p, int policy, -+ const struct sched_param *param) -+{ -+ return __sched_setscheduler(p, policy, param, false); -+} -+ -+static int -+do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param) -+{ -+ struct sched_param lparam; -+ struct task_struct *p; -+ int retval; -+ -+ if (!param || pid < 0) -+ return -EINVAL; -+ if (copy_from_user(&lparam, param, sizeof(struct sched_param))) -+ return -EFAULT; -+ -+ rcu_read_lock(); -+ retval = -ESRCH; -+ p = find_process_by_pid(pid); -+ if (p != NULL) -+ retval = sched_setscheduler(p, policy, &lparam); -+ rcu_read_unlock(); -+ -+ return retval; -+} -+ -+/** -+ * sys_sched_setscheduler - set/change the scheduler policy and RT priority -+ * @pid: the pid in question. -+ * @policy: new policy. -+ * @param: structure containing the new RT priority. -+ */ -+asmlinkage long sys_sched_setscheduler(pid_t pid, int policy, -+ struct sched_param __user *param) -+{ -+ /* negative values for policy are not valid */ -+ if (policy < 0) -+ return -EINVAL; -+ -+ return do_sched_setscheduler(pid, policy, param); -+} -+ -+/** -+ * sys_sched_setparam - set/change the RT priority of a thread -+ * @pid: the pid in question. -+ * @param: structure containing the new RT priority. -+ */ -+SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param) -+{ -+ return do_sched_setscheduler(pid, -1, param); -+} -+ -+/** -+ * sys_sched_getscheduler - get the policy (scheduling class) of a thread -+ * @pid: the pid in question. -+ */ -+SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid) -+{ -+ struct task_struct *p; -+ int retval = -EINVAL; -+ -+ if (pid < 0) -+ goto out_nounlock; -+ -+ retval = -ESRCH; -+ rcu_read_lock(); -+ p = find_process_by_pid(pid); -+ if (p) { -+ retval = security_task_getscheduler(p); -+ if (!retval) -+ retval = p->policy; -+ } -+ rcu_read_unlock(); -+ -+out_nounlock: -+ return retval; -+} -+ -+/** -+ * sys_sched_getscheduler - get the RT priority of a thread -+ * @pid: the pid in question. -+ * @param: structure containing the RT priority. -+ */ -+SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param) -+{ -+ struct sched_param lp; -+ struct task_struct *p; -+ int retval = -EINVAL; -+ -+ if (!param || pid < 0) -+ goto out_nounlock; -+ -+ rcu_read_lock(); -+ p = find_process_by_pid(pid); -+ retval = -ESRCH; -+ if (!p) -+ goto out_unlock; -+ -+ retval = security_task_getscheduler(p); -+ if (retval) -+ goto out_unlock; -+ -+ lp.sched_priority = p->rt_priority; -+ rcu_read_unlock(); -+ -+ /* -+ * This one might sleep, we cannot do it with a spinlock held ... -+ */ -+ retval = copy_to_user(param, &lp, sizeof(*param)) ? -EFAULT : 0; -+ -+out_nounlock: -+ return retval; -+ -+out_unlock: -+ rcu_read_unlock(); -+ return retval; -+} -+ -+long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) -+{ -+ cpumask_var_t cpus_allowed, new_mask; -+ struct task_struct *p; -+ int retval; -+ -+ get_online_cpus(); -+ rcu_read_lock(); -+ -+ p = find_process_by_pid(pid); -+ if (!p) { -+ rcu_read_unlock(); -+ put_online_cpus(); -+ return -ESRCH; -+ } -+ -+ /* Prevent p going away */ -+ get_task_struct(p); -+ rcu_read_unlock(); -+ -+ if (p->flags & PF_NO_SETAFFINITY) { -+ retval = -EINVAL; -+ goto out_put_task; -+ } -+ if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) { -+ retval = -ENOMEM; -+ goto out_put_task; -+ } -+ if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) { -+ retval = -ENOMEM; -+ goto out_free_cpus_allowed; -+ } -+ retval = -EPERM; -+ if (!check_same_owner(p)) { -+ rcu_read_lock(); -+ if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) { -+ rcu_read_unlock(); -+ goto out_unlock; -+ } -+ rcu_read_unlock(); -+ } -+ -+ retval = security_task_setscheduler(p); -+ if (retval) -+ goto out_unlock; -+ -+ cpuset_cpus_allowed(p, cpus_allowed); -+ cpumask_and(new_mask, in_mask, cpus_allowed); -+again: -+ retval = set_cpus_allowed_ptr(p, new_mask); -+ -+ if (!retval) { -+ cpuset_cpus_allowed(p, cpus_allowed); -+ if (!cpumask_subset(new_mask, cpus_allowed)) { -+ /* -+ * We must have raced with a concurrent cpuset -+ * update. Just reset the cpus_allowed to the -+ * cpuset's cpus_allowed -+ */ -+ cpumask_copy(new_mask, cpus_allowed); -+ goto again; -+ } -+ } -+out_unlock: -+ free_cpumask_var(new_mask); -+out_free_cpus_allowed: -+ free_cpumask_var(cpus_allowed); -+out_put_task: -+ put_task_struct(p); -+ put_online_cpus(); -+ return retval; -+} -+ -+static int get_user_cpu_mask(unsigned long __user *user_mask_ptr, unsigned len, -+ cpumask_t *new_mask) -+{ -+ if (len < sizeof(cpumask_t)) { -+ memset(new_mask, 0, sizeof(cpumask_t)); -+ } else if (len > sizeof(cpumask_t)) { -+ len = sizeof(cpumask_t); -+ } -+ return copy_from_user(new_mask, user_mask_ptr, len) ? -EFAULT : 0; -+} -+ -+ -+/** -+ * sys_sched_setaffinity - set the cpu affinity of a process -+ * @pid: pid of the process -+ * @len: length in bytes of the bitmask pointed to by user_mask_ptr -+ * @user_mask_ptr: user-space pointer to the new cpu mask -+ */ -+SYSCALL_DEFINE3(sched_setaffinity, pid_t, pid, unsigned int, len, -+ unsigned long __user *, user_mask_ptr) -+{ -+ cpumask_var_t new_mask; -+ int retval; -+ -+ if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) -+ return -ENOMEM; -+ -+ retval = get_user_cpu_mask(user_mask_ptr, len, new_mask); -+ if (retval == 0) -+ retval = sched_setaffinity(pid, new_mask); -+ free_cpumask_var(new_mask); -+ return retval; -+} -+ -+long sched_getaffinity(pid_t pid, cpumask_t *mask) -+{ -+ struct task_struct *p; -+ unsigned long flags; -+ int retval; -+ -+ get_online_cpus(); -+ rcu_read_lock(); -+ -+ retval = -ESRCH; -+ p = find_process_by_pid(pid); -+ if (!p) -+ goto out_unlock; -+ -+ retval = security_task_getscheduler(p); -+ if (retval) -+ goto out_unlock; -+ -+ grq_lock_irqsave(&flags); -+ cpumask_and(mask, tsk_cpus_allowed(p), cpu_online_mask); -+ grq_unlock_irqrestore(&flags); -+ -+out_unlock: -+ rcu_read_unlock(); -+ put_online_cpus(); -+ -+ return retval; -+} -+ -+/** -+ * sys_sched_getaffinity - get the cpu affinity of a process -+ * @pid: pid of the process -+ * @len: length in bytes of the bitmask pointed to by user_mask_ptr -+ * @user_mask_ptr: user-space pointer to hold the current cpu mask -+ */ -+SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len, -+ unsigned long __user *, user_mask_ptr) -+{ -+ int ret; -+ cpumask_var_t mask; -+ -+ if ((len * BITS_PER_BYTE) < nr_cpu_ids) -+ return -EINVAL; -+ if (len & (sizeof(unsigned long)-1)) -+ return -EINVAL; -+ -+ if (!alloc_cpumask_var(&mask, GFP_KERNEL)) -+ return -ENOMEM; -+ -+ ret = sched_getaffinity(pid, mask); -+ if (ret == 0) { -+ size_t retlen = min_t(size_t, len, cpumask_size()); -+ -+ if (copy_to_user(user_mask_ptr, mask, retlen)) -+ ret = -EFAULT; -+ else -+ ret = retlen; -+ } -+ free_cpumask_var(mask); -+ -+ return ret; -+} -+ -+/** -+ * sys_sched_yield - yield the current processor to other threads. -+ * -+ * This function yields the current CPU to other tasks. It does this by -+ * scheduling away the current task. If it still has the earliest deadline -+ * it will be scheduled again as the next task. -+ */ -+SYSCALL_DEFINE0(sched_yield) -+{ -+ struct task_struct *p; -+ -+ p = current; -+ grq_lock_irq(); -+ schedstat_inc(task_rq(p), yld_count); -+ requeue_task(p); -+ -+ /* -+ * Since we are going to call schedule() anyway, there's -+ * no need to preempt or enable interrupts: -+ */ -+ __release(grq.lock); -+ spin_release(&grq.lock.dep_map, 1, _THIS_IP_); -+ do_raw_spin_unlock(&grq.lock); -+ sched_preempt_enable_no_resched(); -+ -+ schedule(); -+ -+ return 0; -+} -+ -+static inline bool should_resched(void) -+{ -+ return need_resched() && !(preempt_count() & PREEMPT_ACTIVE); -+} -+ -+static void __cond_resched(void) -+{ -+ add_preempt_count(PREEMPT_ACTIVE); -+ schedule(); -+ sub_preempt_count(PREEMPT_ACTIVE); -+} -+ -+int __sched _cond_resched(void) -+{ -+ if (should_resched()) { -+ __cond_resched(); -+ return 1; -+ } -+ return 0; -+} -+EXPORT_SYMBOL(_cond_resched); -+ -+/* -+ * __cond_resched_lock() - if a reschedule is pending, drop the given lock, -+ * call schedule, and on return reacquire the lock. -+ * -+ * This works OK both with and without CONFIG_PREEMPT. We do strange low-level -+ * operations here to prevent schedule() from being called twice (once via -+ * spin_unlock(), once by hand). -+ */ -+int __cond_resched_lock(spinlock_t *lock) -+{ -+ int resched = should_resched(); -+ int ret = 0; -+ -+ lockdep_assert_held(lock); -+ -+ if (spin_needbreak(lock) || resched) { -+ spin_unlock(lock); -+ if (resched) -+ __cond_resched(); -+ else -+ cpu_relax(); -+ ret = 1; -+ spin_lock(lock); -+ } -+ return ret; -+} -+EXPORT_SYMBOL(__cond_resched_lock); -+ -+int __sched __cond_resched_softirq(void) -+{ -+ BUG_ON(!in_softirq()); -+ -+ if (should_resched()) { -+ local_bh_enable(); -+ __cond_resched(); -+ local_bh_disable(); -+ return 1; -+ } -+ return 0; -+} -+EXPORT_SYMBOL(__cond_resched_softirq); -+ -+/** -+ * yield - yield the current processor to other threads. -+ * -+ * Do not ever use this function, there's a 99% chance you're doing it wrong. -+ * -+ * The scheduler is at all times free to pick the calling task as the most -+ * eligible task to run, if removing the yield() call from your code breaks -+ * it, its already broken. -+ * -+ * Typical broken usage is: -+ * -+ * while (!event) -+ * yield(); -+ * -+ * where one assumes that yield() will let 'the other' process run that will -+ * make event true. If the current task is a SCHED_FIFO task that will never -+ * happen. Never use yield() as a progress guarantee!! -+ * -+ * If you want to use yield() to wait for something, use wait_event(). -+ * If you want to use yield() to be 'nice' for others, use cond_resched(). -+ * If you still want to use yield(), do not! -+ */ -+void __sched yield(void) -+{ -+ set_current_state(TASK_RUNNING); -+ sys_sched_yield(); -+} -+EXPORT_SYMBOL(yield); -+ -+/** -+ * yield_to - yield the current processor to another thread in -+ * your thread group, or accelerate that thread toward the -+ * processor it's on. -+ * @p: target task -+ * @preempt: whether task preemption is allowed or not -+ * -+ * It's the caller's job to ensure that the target task struct -+ * can't go away on us before we can do any checks. -+ * -+ * Returns: -+ * true (>0) if we indeed boosted the target task. -+ * false (0) if we failed to boost the target. -+ * -ESRCH if there's no task to yield to. -+ */ -+bool __sched yield_to(struct task_struct *p, bool preempt) -+{ -+ unsigned long flags; -+ int yielded = 0; -+ struct rq *rq; -+ -+ rq = this_rq(); -+ grq_lock_irqsave(&flags); -+ if (task_running(p) || p->state) { -+ yielded = -ESRCH; -+ goto out_unlock; -+ } -+ yielded = 1; -+ if (p->deadline > rq->rq_deadline) -+ p->deadline = rq->rq_deadline; -+ p->time_slice += rq->rq_time_slice; -+ rq->rq_time_slice = 0; -+ if (p->time_slice > timeslice()) -+ p->time_slice = timeslice(); -+ set_tsk_need_resched(rq->curr); -+out_unlock: -+ grq_unlock_irqrestore(&flags); -+ -+ if (yielded > 0) -+ schedule(); -+ return yielded; -+} -+EXPORT_SYMBOL_GPL(yield_to); -+ -+/* -+ * This task is about to go to sleep on IO. Increment rq->nr_iowait so -+ * that process accounting knows that this is a task in IO wait state. -+ * -+ * But don't do that if it is a deliberate, throttling IO wait (this task -+ * has set its backing_dev_info: the queue against which it should throttle) -+ */ -+void __sched io_schedule(void) -+{ -+ struct rq *rq = raw_rq(); -+ -+ delayacct_blkio_start(); -+ atomic_inc(&rq->nr_iowait); -+ blk_flush_plug(current); -+ current->in_iowait = 1; -+ schedule(); -+ current->in_iowait = 0; -+ atomic_dec(&rq->nr_iowait); -+ delayacct_blkio_end(); -+} -+EXPORT_SYMBOL(io_schedule); -+ -+long __sched io_schedule_timeout(long timeout) -+{ -+ struct rq *rq = raw_rq(); -+ long ret; -+ -+ delayacct_blkio_start(); -+ atomic_inc(&rq->nr_iowait); -+ blk_flush_plug(current); -+ current->in_iowait = 1; -+ ret = schedule_timeout(timeout); -+ current->in_iowait = 0; -+ atomic_dec(&rq->nr_iowait); -+ delayacct_blkio_end(); -+ return ret; -+} -+ -+/** -+ * sys_sched_get_priority_max - return maximum RT priority. -+ * @policy: scheduling class. -+ * -+ * this syscall returns the maximum rt_priority that can be used -+ * by a given scheduling class. -+ */ -+SYSCALL_DEFINE1(sched_get_priority_max, int, policy) -+{ -+ int ret = -EINVAL; -+ -+ switch (policy) { -+ case SCHED_FIFO: -+ case SCHED_RR: -+ ret = MAX_USER_RT_PRIO-1; -+ break; -+ case SCHED_NORMAL: -+ case SCHED_BATCH: -+ case SCHED_ISO: -+ case SCHED_IDLEPRIO: -+ ret = 0; -+ break; -+ } -+ return ret; -+} -+ -+/** -+ * sys_sched_get_priority_min - return minimum RT priority. -+ * @policy: scheduling class. -+ * -+ * this syscall returns the minimum rt_priority that can be used -+ * by a given scheduling class. -+ */ -+SYSCALL_DEFINE1(sched_get_priority_min, int, policy) -+{ -+ int ret = -EINVAL; -+ -+ switch (policy) { -+ case SCHED_FIFO: -+ case SCHED_RR: -+ ret = 1; -+ break; -+ case SCHED_NORMAL: -+ case SCHED_BATCH: -+ case SCHED_ISO: -+ case SCHED_IDLEPRIO: -+ ret = 0; -+ break; -+ } -+ return ret; -+} -+ -+/** -+ * sys_sched_rr_get_interval - return the default timeslice of a process. -+ * @pid: pid of the process. -+ * @interval: userspace pointer to the timeslice value. -+ * -+ * this syscall writes the default timeslice value of a given process -+ * into the user-space timespec buffer. A value of '0' means infinity. -+ */ -+SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid, -+ struct timespec __user *, interval) -+{ -+ struct task_struct *p; -+ unsigned int time_slice; -+ unsigned long flags; -+ int retval; -+ struct timespec t; -+ -+ if (pid < 0) -+ return -EINVAL; -+ -+ retval = -ESRCH; -+ rcu_read_lock(); -+ p = find_process_by_pid(pid); -+ if (!p) -+ goto out_unlock; -+ -+ retval = security_task_getscheduler(p); -+ if (retval) -+ goto out_unlock; -+ -+ grq_lock_irqsave(&flags); -+ time_slice = p->policy == SCHED_FIFO ? 0 : MS_TO_NS(task_timeslice(p)); -+ grq_unlock_irqrestore(&flags); -+ -+ rcu_read_unlock(); -+ t = ns_to_timespec(time_slice); -+ retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0; -+ return retval; -+ -+out_unlock: -+ rcu_read_unlock(); -+ return retval; -+} -+ -+static const char stat_nam[] = TASK_STATE_TO_CHAR_STR; -+ -+void sched_show_task(struct task_struct *p) -+{ -+ unsigned long free = 0; -+ int ppid; -+ unsigned state; -+ -+ state = p->state ? __ffs(p->state) + 1 : 0; -+ printk(KERN_INFO "%-15.15s %c", p->comm, -+ state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?'); -+#if BITS_PER_LONG == 32 -+ if (state == TASK_RUNNING) -+ printk(KERN_CONT " running "); -+ else -+ printk(KERN_CONT " %08lx ", thread_saved_pc(p)); -+#else -+ if (state == TASK_RUNNING) -+ printk(KERN_CONT " running task "); -+ else -+ printk(KERN_CONT " %016lx ", thread_saved_pc(p)); -+#endif -+#ifdef CONFIG_DEBUG_STACK_USAGE -+ free = stack_not_used(p); -+#endif -+ rcu_read_lock(); -+ ppid = task_pid_nr(rcu_dereference(p->real_parent)); -+ rcu_read_unlock(); -+ printk(KERN_CONT "%5lu %5d %6d 0x%08lx\n", free, -+ task_pid_nr(p), ppid, -+ (unsigned long)task_thread_info(p)->flags); -+ -+ print_worker_info(KERN_INFO, p); -+ show_stack(p, NULL); -+} -+ -+void show_state_filter(unsigned long state_filter) -+{ -+ struct task_struct *g, *p; -+ -+#if BITS_PER_LONG == 32 -+ printk(KERN_INFO -+ " task PC stack pid father\n"); -+#else -+ printk(KERN_INFO -+ " task PC stack pid father\n"); -+#endif -+ rcu_read_lock(); -+ do_each_thread(g, p) { -+ /* -+ * reset the NMI-timeout, listing all files on a slow -+ * console might take a lot of time: -+ */ -+ touch_nmi_watchdog(); -+ if (!state_filter || (p->state & state_filter)) -+ sched_show_task(p); -+ } while_each_thread(g, p); -+ -+ touch_all_softlockup_watchdogs(); -+ -+ rcu_read_unlock(); -+ /* -+ * Only show locks if all tasks are dumped: -+ */ -+ if (!state_filter) -+ debug_show_all_locks(); -+} -+ -+void dump_cpu_task(int cpu) -+{ -+ pr_info("Task dump for CPU %d:\n", cpu); -+ sched_show_task(cpu_curr(cpu)); -+} -+ -+#ifdef CONFIG_SMP -+void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) -+{ -+ cpumask_copy(tsk_cpus_allowed(p), new_mask); -+} -+#endif -+ -+/** -+ * init_idle - set up an idle thread for a given CPU -+ * @idle: task in question -+ * @cpu: cpu the idle task belongs to -+ * -+ * NOTE: this function does not set the idle thread's NEED_RESCHED -+ * flag, to make booting more robust. -+ */ -+void init_idle(struct task_struct *idle, int cpu) -+{ -+ struct rq *rq = cpu_rq(cpu); -+ unsigned long flags; -+ -+ time_grq_lock(rq, &flags); -+ idle->last_ran = rq->clock_task; -+ idle->state = TASK_RUNNING; -+ /* Setting prio to illegal value shouldn't matter when never queued */ -+ idle->prio = PRIO_LIMIT; -+ set_rq_task(rq, idle); -+ do_set_cpus_allowed(idle, &cpumask_of_cpu(cpu)); -+ /* Silence PROVE_RCU */ -+ rcu_read_lock(); -+ set_task_cpu(idle, cpu); -+ rcu_read_unlock(); -+ rq->curr = rq->idle = idle; -+ idle->on_cpu = 1; -+ grq_unlock_irqrestore(&flags); -+ -+ /* Set the preempt count _outside_ the spinlocks! */ -+ task_thread_info(idle)->preempt_count = 0; -+ -+ ftrace_graph_init_idle_task(idle, cpu); -+#if defined(CONFIG_SMP) -+ sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu); -+#endif -+} -+ -+#ifdef CONFIG_SMP -+#ifdef CONFIG_NO_HZ_COMMON -+void nohz_balance_enter_idle(int cpu) -+{ -+} -+ -+void select_nohz_load_balancer(int stop_tick) -+{ -+} -+ -+void set_cpu_sd_state_idle(void) {} -+#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) -+/** -+ * lowest_flag_domain - Return lowest sched_domain containing flag. -+ * @cpu: The cpu whose lowest level of sched domain is to -+ * be returned. -+ * @flag: The flag to check for the lowest sched_domain -+ * for the given cpu. -+ * -+ * Returns the lowest sched_domain of a cpu which contains the given flag. -+ */ -+static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) -+{ -+ struct sched_domain *sd; -+ -+ for_each_domain(cpu, sd) -+ if (sd && (sd->flags & flag)) -+ break; -+ -+ return sd; -+} -+ -+/** -+ * for_each_flag_domain - Iterates over sched_domains containing the flag. -+ * @cpu: The cpu whose domains we're iterating over. -+ * @sd: variable holding the value of the power_savings_sd -+ * for cpu. -+ * @flag: The flag to filter the sched_domains to be iterated. -+ * -+ * Iterates over all the scheduler domains for a given cpu that has the 'flag' -+ * set, starting from the lowest sched_domain to the highest. -+ */ -+#define for_each_flag_domain(cpu, sd, flag) \ -+ for (sd = lowest_flag_domain(cpu, flag); \ -+ (sd && (sd->flags & flag)); sd = sd->parent) -+ -+#endif /* (CONFIG_SCHED_MC || CONFIG_SCHED_SMT) */ -+ -+static inline void resched_cpu(int cpu) -+{ -+ unsigned long flags; -+ -+ grq_lock_irqsave(&flags); -+ resched_task(cpu_curr(cpu)); -+ grq_unlock_irqrestore(&flags); -+} -+ -+/* -+ * In the semi idle case, use the nearest busy cpu for migrating timers -+ * from an idle cpu. This is good for power-savings. -+ * -+ * We don't do similar optimization for completely idle system, as -+ * selecting an idle cpu will add more delays to the timers than intended -+ * (as that cpu's timer base may not be uptodate wrt jiffies etc). -+ */ -+int get_nohz_timer_target(void) -+{ -+ int cpu = smp_processor_id(); -+ int i; -+ struct sched_domain *sd; -+ -+ rcu_read_lock(); -+ for_each_domain(cpu, sd) { -+ for_each_cpu(i, sched_domain_span(sd)) { -+ if (!idle_cpu(i)) -+ cpu = i; -+ goto unlock; -+ } -+ } -+unlock: -+ rcu_read_unlock(); -+ return cpu; -+} -+ -+/* -+ * When add_timer_on() enqueues a timer into the timer wheel of an -+ * idle CPU then this timer might expire before the next timer event -+ * which is scheduled to wake up that CPU. In case of a completely -+ * idle system the next event might even be infinite time into the -+ * future. wake_up_idle_cpu() ensures that the CPU is woken up and -+ * leaves the inner idle loop so the newly added timer is taken into -+ * account when the CPU goes back to idle and evaluates the timer -+ * wheel for the next timer event. -+ */ -+void wake_up_idle_cpu(int cpu) -+{ -+ struct task_struct *idle; -+ struct rq *rq; -+ -+ if (cpu == smp_processor_id()) -+ return; -+ -+ rq = cpu_rq(cpu); -+ idle = rq->idle; -+ -+ /* -+ * This is safe, as this function is called with the timer -+ * wheel base lock of (cpu) held. When the CPU is on the way -+ * to idle and has not yet set rq->curr to idle then it will -+ * be serialised on the timer wheel base lock and take the new -+ * timer into account automatically. -+ */ -+ if (unlikely(rq->curr != idle)) -+ return; -+ -+ /* -+ * We can set TIF_RESCHED on the idle task of the other CPU -+ * lockless. The worst case is that the other CPU runs the -+ * idle task through an additional NOOP schedule() -+ */ -+ set_tsk_need_resched(idle); -+ -+ /* NEED_RESCHED must be visible before we test polling */ -+ smp_mb(); -+ if (!tsk_is_polling(idle)) -+ smp_send_reschedule(cpu); -+} -+ -+void wake_up_nohz_cpu(int cpu) -+{ -+ wake_up_idle_cpu(cpu); -+} -+#endif /* CONFIG_NO_HZ_COMMON */ -+ -+/* -+ * Change a given task's CPU affinity. Migrate the thread to a -+ * proper CPU and schedule it away if the CPU it's executing on -+ * is removed from the allowed bitmask. -+ * -+ * NOTE: the caller must have a valid reference to the task, the -+ * task must not exit() & deallocate itself prematurely. The -+ * call is not atomic; no spinlocks may be held. -+ */ -+int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) -+{ -+ bool running_wrong = false; -+ bool queued = false; -+ unsigned long flags; -+ struct rq *rq; -+ int ret = 0; -+ -+ rq = task_grq_lock(p, &flags); -+ -+ if (cpumask_equal(tsk_cpus_allowed(p), new_mask)) -+ goto out; -+ -+ if (!cpumask_intersects(new_mask, cpu_active_mask)) { -+ ret = -EINVAL; -+ goto out; -+ } -+ -+ queued = task_queued(p); -+ -+ do_set_cpus_allowed(p, new_mask); -+ -+ /* Can the task run on the task's current CPU? If so, we're done */ -+ if (cpumask_test_cpu(task_cpu(p), new_mask)) -+ goto out; -+ -+ if (task_running(p)) { -+ /* Task is running on the wrong cpu now, reschedule it. */ -+ if (rq == this_rq()) { -+ set_tsk_need_resched(p); -+ running_wrong = true; -+ } else -+ resched_task(p); -+ } else -+ set_task_cpu(p, cpumask_any_and(cpu_active_mask, new_mask)); -+ -+out: -+ if (queued) -+ try_preempt(p, rq); -+ task_grq_unlock(&flags); -+ -+ if (running_wrong) -+ _cond_resched(); -+ -+ return ret; -+} -+EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr); -+ -+#ifdef CONFIG_HOTPLUG_CPU -+extern struct task_struct *cpu_stopper_task; -+/* Run through task list and find tasks affined to just the dead cpu, then -+ * allocate a new affinity */ -+static void break_sole_affinity(int src_cpu, struct task_struct *idle) -+{ -+ struct task_struct *p, *t, *stopper; -+ -+ stopper = per_cpu(cpu_stopper_task, src_cpu); -+ do_each_thread(t, p) { -+ if (p != stopper && p != idle && !online_cpus(p)) { -+ cpumask_copy(tsk_cpus_allowed(p), cpu_possible_mask); -+ /* -+ * Don't tell them about moving exiting tasks or -+ * kernel threads (both mm NULL), since they never -+ * leave kernel. -+ */ -+ if (p->mm && printk_ratelimit()) { -+ printk(KERN_INFO "process %d (%s) no " -+ "longer affine to cpu %d\n", -+ task_pid_nr(p), p->comm, src_cpu); -+ } -+ } -+ clear_sticky(p); -+ } while_each_thread(t, p); -+} -+ -+/* -+ * Ensures that the idle task is using init_mm right before its cpu goes -+ * offline. -+ */ -+void idle_task_exit(void) -+{ -+ struct mm_struct *mm = current->active_mm; -+ -+ BUG_ON(cpu_online(smp_processor_id())); -+ -+ if (mm != &init_mm) -+ switch_mm(mm, &init_mm, current); -+ mmdrop(mm); -+} -+#endif /* CONFIG_HOTPLUG_CPU */ -+void sched_set_stop_task(int cpu, struct task_struct *stop) -+{ -+ struct sched_param stop_param = { .sched_priority = STOP_PRIO }; -+ struct sched_param start_param = { .sched_priority = 0 }; -+ struct task_struct *old_stop = cpu_rq(cpu)->stop; -+ -+ if (stop) { -+ /* -+ * Make it appear like a SCHED_FIFO task, its something -+ * userspace knows about and won't get confused about. -+ * -+ * Also, it will make PI more or less work without too -+ * much confusion -- but then, stop work should not -+ * rely on PI working anyway. -+ */ -+ sched_setscheduler_nocheck(stop, SCHED_FIFO, &stop_param); -+ } -+ -+ cpu_rq(cpu)->stop = stop; -+ -+ if (old_stop) { -+ /* -+ * Reset it back to a normal scheduling policy so that -+ * it can die in pieces. -+ */ -+ sched_setscheduler_nocheck(old_stop, SCHED_NORMAL, &start_param); -+ } -+} -+ -+ -+#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL) -+ -+static struct ctl_table sd_ctl_dir[] = { -+ { -+ .procname = "sched_domain", -+ .mode = 0555, -+ }, -+ {} -+}; -+ -+static struct ctl_table sd_ctl_root[] = { -+ { -+ .procname = "kernel", -+ .mode = 0555, -+ .child = sd_ctl_dir, -+ }, -+ {} -+}; -+ -+static struct ctl_table *sd_alloc_ctl_entry(int n) -+{ -+ struct ctl_table *entry = -+ kcalloc(n, sizeof(struct ctl_table), GFP_KERNEL); -+ -+ return entry; -+} -+ -+static void sd_free_ctl_entry(struct ctl_table **tablep) -+{ -+ struct ctl_table *entry; -+ -+ /* -+ * In the intermediate directories, both the child directory and -+ * procname are dynamically allocated and could fail but the mode -+ * will always be set. In the lowest directory the names are -+ * static strings and all have proc handlers. -+ */ -+ for (entry = *tablep; entry->mode; entry++) { -+ if (entry->child) -+ sd_free_ctl_entry(&entry->child); -+ if (entry->proc_handler == NULL) -+ kfree(entry->procname); -+ } -+ -+ kfree(*tablep); -+ *tablep = NULL; -+} -+ -+static void -+set_table_entry(struct ctl_table *entry, -+ const char *procname, void *data, int maxlen, -+ mode_t mode, proc_handler *proc_handler) -+{ -+ entry->procname = procname; -+ entry->data = data; -+ entry->maxlen = maxlen; -+ entry->mode = mode; -+ entry->proc_handler = proc_handler; -+} -+ -+static struct ctl_table * -+sd_alloc_ctl_domain_table(struct sched_domain *sd) -+{ -+ struct ctl_table *table = sd_alloc_ctl_entry(13); -+ -+ if (table == NULL) -+ return NULL; -+ -+ set_table_entry(&table[0], "min_interval", &sd->min_interval, -+ sizeof(long), 0644, proc_doulongvec_minmax); -+ set_table_entry(&table[1], "max_interval", &sd->max_interval, -+ sizeof(long), 0644, proc_doulongvec_minmax); -+ set_table_entry(&table[2], "busy_idx", &sd->busy_idx, -+ sizeof(int), 0644, proc_dointvec_minmax); -+ set_table_entry(&table[3], "idle_idx", &sd->idle_idx, -+ sizeof(int), 0644, proc_dointvec_minmax); -+ set_table_entry(&table[4], "newidle_idx", &sd->newidle_idx, -+ sizeof(int), 0644, proc_dointvec_minmax); -+ set_table_entry(&table[5], "wake_idx", &sd->wake_idx, -+ sizeof(int), 0644, proc_dointvec_minmax); -+ set_table_entry(&table[6], "forkexec_idx", &sd->forkexec_idx, -+ sizeof(int), 0644, proc_dointvec_minmax); -+ set_table_entry(&table[7], "busy_factor", &sd->busy_factor, -+ sizeof(int), 0644, proc_dointvec_minmax); -+ set_table_entry(&table[8], "imbalance_pct", &sd->imbalance_pct, -+ sizeof(int), 0644, proc_dointvec_minmax); -+ set_table_entry(&table[9], "cache_nice_tries", -+ &sd->cache_nice_tries, -+ sizeof(int), 0644, proc_dointvec_minmax); -+ set_table_entry(&table[10], "flags", &sd->flags, -+ sizeof(int), 0644, proc_dointvec_minmax); -+ set_table_entry(&table[11], "name", sd->name, -+ CORENAME_MAX_SIZE, 0444, proc_dostring); -+ /* &table[12] is terminator */ -+ -+ return table; -+} -+ -+static ctl_table *sd_alloc_ctl_cpu_table(int cpu) -+{ -+ struct ctl_table *entry, *table; -+ struct sched_domain *sd; -+ int domain_num = 0, i; -+ char buf[32]; -+ -+ for_each_domain(cpu, sd) -+ domain_num++; -+ entry = table = sd_alloc_ctl_entry(domain_num + 1); -+ if (table == NULL) -+ return NULL; -+ -+ i = 0; -+ for_each_domain(cpu, sd) { -+ snprintf(buf, 32, "domain%d", i); -+ entry->procname = kstrdup(buf, GFP_KERNEL); -+ entry->mode = 0555; -+ entry->child = sd_alloc_ctl_domain_table(sd); -+ entry++; -+ i++; -+ } -+ return table; -+} -+ -+static struct ctl_table_header *sd_sysctl_header; -+static void register_sched_domain_sysctl(void) -+{ -+ int i, cpu_num = num_possible_cpus(); -+ struct ctl_table *entry = sd_alloc_ctl_entry(cpu_num + 1); -+ char buf[32]; -+ -+ WARN_ON(sd_ctl_dir[0].child); -+ sd_ctl_dir[0].child = entry; -+ -+ if (entry == NULL) -+ return; -+ -+ for_each_possible_cpu(i) { -+ snprintf(buf, 32, "cpu%d", i); -+ entry->procname = kstrdup(buf, GFP_KERNEL); -+ entry->mode = 0555; -+ entry->child = sd_alloc_ctl_cpu_table(i); -+ entry++; -+ } -+ -+ WARN_ON(sd_sysctl_header); -+ sd_sysctl_header = register_sysctl_table(sd_ctl_root); -+} -+ -+/* may be called multiple times per register */ -+static void unregister_sched_domain_sysctl(void) -+{ -+ if (sd_sysctl_header) -+ unregister_sysctl_table(sd_sysctl_header); -+ sd_sysctl_header = NULL; -+ if (sd_ctl_dir[0].child) -+ sd_free_ctl_entry(&sd_ctl_dir[0].child); -+} -+#else -+static void register_sched_domain_sysctl(void) -+{ -+} -+static void unregister_sched_domain_sysctl(void) -+{ -+} -+#endif -+ -+static void set_rq_online(struct rq *rq) -+{ -+ if (!rq->online) { -+ cpumask_set_cpu(cpu_of(rq), rq->rd->online); -+ rq->online = true; -+ } -+} -+ -+static void set_rq_offline(struct rq *rq) -+{ -+ if (rq->online) { -+ cpumask_clear_cpu(cpu_of(rq), rq->rd->online); -+ rq->online = false; -+ } -+} -+ -+/* -+ * migration_call - callback that gets triggered when a CPU is added. -+ */ -+static int __cpuinit -+migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) -+{ -+ int cpu = (long)hcpu; -+ unsigned long flags; -+ struct rq *rq = cpu_rq(cpu); -+#ifdef CONFIG_HOTPLUG_CPU -+ struct task_struct *idle = rq->idle; -+#endif -+ -+ switch (action & ~CPU_TASKS_FROZEN) { -+ -+ case CPU_UP_PREPARE: -+ break; -+ -+ case CPU_ONLINE: -+ /* Update our root-domain */ -+ grq_lock_irqsave(&flags); -+ if (rq->rd) { -+ BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); -+ -+ set_rq_online(rq); -+ } -+ grq.noc = num_online_cpus(); -+ grq_unlock_irqrestore(&flags); -+ break; -+ -+#ifdef CONFIG_HOTPLUG_CPU -+ case CPU_DEAD: -+ /* Idle task back to normal (off runqueue, low prio) */ -+ grq_lock_irq(); -+ return_task(idle, true); -+ idle->static_prio = MAX_PRIO; -+ __setscheduler(idle, rq, SCHED_NORMAL, 0); -+ idle->prio = PRIO_LIMIT; -+ set_rq_task(rq, idle); -+ update_clocks(rq); -+ grq_unlock_irq(); -+ break; -+ -+ case CPU_DYING: -+ /* Update our root-domain */ -+ grq_lock_irqsave(&flags); -+ if (rq->rd) { -+ BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); -+ set_rq_offline(rq); -+ } -+ break_sole_affinity(cpu, idle); -+ grq.noc = num_online_cpus(); -+ grq_unlock_irqrestore(&flags); -+ break; -+#endif -+ } -+ return NOTIFY_OK; -+} -+ -+/* -+ * Register at high priority so that task migration (migrate_all_tasks) -+ * happens before everything else. This has to be lower priority than -+ * the notifier in the perf_counter subsystem, though. -+ */ -+static struct notifier_block __cpuinitdata migration_notifier = { -+ .notifier_call = migration_call, -+ .priority = CPU_PRI_MIGRATION, -+}; -+ -+static int __cpuinit sched_cpu_active(struct notifier_block *nfb, -+ unsigned long action, void *hcpu) -+{ -+ switch (action & ~CPU_TASKS_FROZEN) { -+ case CPU_STARTING: -+ case CPU_DOWN_FAILED: -+ set_cpu_active((long)hcpu, true); -+ return NOTIFY_OK; -+ default: -+ return NOTIFY_DONE; -+ } -+} -+ -+static int __cpuinit sched_cpu_inactive(struct notifier_block *nfb, -+ unsigned long action, void *hcpu) -+{ -+ switch (action & ~CPU_TASKS_FROZEN) { -+ case CPU_DOWN_PREPARE: -+ set_cpu_active((long)hcpu, false); -+ return NOTIFY_OK; -+ default: -+ return NOTIFY_DONE; -+ } -+} -+ -+int __init migration_init(void) -+{ -+ void *cpu = (void *)(long)smp_processor_id(); -+ int err; -+ -+ /* Initialise migration for the boot CPU */ -+ err = migration_call(&migration_notifier, CPU_UP_PREPARE, cpu); -+ BUG_ON(err == NOTIFY_BAD); -+ migration_call(&migration_notifier, CPU_ONLINE, cpu); -+ register_cpu_notifier(&migration_notifier); -+ -+ /* Register cpu active notifiers */ -+ cpu_notifier(sched_cpu_active, CPU_PRI_SCHED_ACTIVE); -+ cpu_notifier(sched_cpu_inactive, CPU_PRI_SCHED_INACTIVE); -+ -+ return 0; -+} -+early_initcall(migration_init); -+#endif -+ -+#ifdef CONFIG_SMP -+ -+static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */ -+ -+#ifdef CONFIG_SCHED_DEBUG -+ -+static __read_mostly int sched_debug_enabled; -+ -+static int __init sched_debug_setup(char *str) -+{ -+ sched_debug_enabled = 1; -+ -+ return 0; -+} -+early_param("sched_debug", sched_debug_setup); -+ -+static inline bool sched_debug(void) -+{ -+ return sched_debug_enabled; -+} -+ -+static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, -+ struct cpumask *groupmask) -+{ -+ char str[256]; -+ -+ cpulist_scnprintf(str, sizeof(str), sched_domain_span(sd)); -+ cpumask_clear(groupmask); -+ -+ printk(KERN_DEBUG "%*s domain %d: ", level, "", level); -+ -+ if (!(sd->flags & SD_LOAD_BALANCE)) { -+ printk("does not load-balance\n"); -+ if (sd->parent) -+ printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain" -+ " has parent"); -+ return -1; -+ } -+ -+ printk(KERN_CONT "span %s level %s\n", str, sd->name); -+ -+ if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) { -+ printk(KERN_ERR "ERROR: domain->span does not contain " -+ "CPU%d\n", cpu); -+ } -+ -+ printk(KERN_CONT "\n"); -+ -+ if (!cpumask_equal(sched_domain_span(sd), groupmask)) -+ printk(KERN_ERR "ERROR: groups don't span domain->span\n"); -+ -+ if (sd->parent && -+ !cpumask_subset(groupmask, sched_domain_span(sd->parent))) -+ printk(KERN_ERR "ERROR: parent span is not a superset " -+ "of domain->span\n"); -+ return 0; -+} -+ -+static void sched_domain_debug(struct sched_domain *sd, int cpu) -+{ -+ int level = 0; -+ -+ if (!sched_debug_enabled) -+ return; -+ -+ if (!sd) { -+ printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu); -+ return; -+ } -+ -+ printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu); -+ -+ for (;;) { -+ if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask)) -+ break; -+ level++; -+ sd = sd->parent; -+ if (!sd) -+ break; -+ } -+} -+#else /* !CONFIG_SCHED_DEBUG */ -+# define sched_domain_debug(sd, cpu) do { } while (0) -+static inline bool sched_debug(void) -+{ -+ return false; -+} -+#endif /* CONFIG_SCHED_DEBUG */ -+ -+static int sd_degenerate(struct sched_domain *sd) -+{ -+ if (cpumask_weight(sched_domain_span(sd)) == 1) -+ return 1; -+ -+ /* Following flags don't use groups */ -+ if (sd->flags & (SD_WAKE_AFFINE)) -+ return 0; -+ -+ return 1; -+} -+ -+static int -+sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent) -+{ -+ unsigned long cflags = sd->flags, pflags = parent->flags; -+ -+ if (sd_degenerate(parent)) -+ return 1; -+ -+ if (!cpumask_equal(sched_domain_span(sd), sched_domain_span(parent))) -+ return 0; -+ -+ if (~cflags & pflags) -+ return 0; -+ -+ return 1; -+} -+ -+static void free_rootdomain(struct rcu_head *rcu) -+{ -+ struct root_domain *rd = container_of(rcu, struct root_domain, rcu); -+ -+ cpupri_cleanup(&rd->cpupri); -+ free_cpumask_var(rd->rto_mask); -+ free_cpumask_var(rd->online); -+ free_cpumask_var(rd->span); -+ kfree(rd); -+} -+ -+static void rq_attach_root(struct rq *rq, struct root_domain *rd) -+{ -+ struct root_domain *old_rd = NULL; -+ unsigned long flags; -+ -+ grq_lock_irqsave(&flags); -+ -+ if (rq->rd) { -+ old_rd = rq->rd; -+ -+ if (cpumask_test_cpu(rq->cpu, old_rd->online)) -+ set_rq_offline(rq); -+ -+ cpumask_clear_cpu(rq->cpu, old_rd->span); -+ -+ /* -+ * If we dont want to free the old_rt yet then -+ * set old_rd to NULL to skip the freeing later -+ * in this function: -+ */ -+ if (!atomic_dec_and_test(&old_rd->refcount)) -+ old_rd = NULL; -+ } -+ -+ atomic_inc(&rd->refcount); -+ rq->rd = rd; -+ -+ cpumask_set_cpu(rq->cpu, rd->span); -+ if (cpumask_test_cpu(rq->cpu, cpu_active_mask)) -+ set_rq_online(rq); -+ -+ grq_unlock_irqrestore(&flags); -+ -+ if (old_rd) -+ call_rcu_sched(&old_rd->rcu, free_rootdomain); -+} -+ -+static int init_rootdomain(struct root_domain *rd) -+{ -+ memset(rd, 0, sizeof(*rd)); -+ -+ if (!alloc_cpumask_var(&rd->span, GFP_KERNEL)) -+ goto out; -+ if (!alloc_cpumask_var(&rd->online, GFP_KERNEL)) -+ goto free_span; -+ if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL)) -+ goto free_online; -+ -+ if (cpupri_init(&rd->cpupri) != 0) -+ goto free_rto_mask; -+ return 0; -+ -+free_rto_mask: -+ free_cpumask_var(rd->rto_mask); -+free_online: -+ free_cpumask_var(rd->online); -+free_span: -+ free_cpumask_var(rd->span); -+out: -+ return -ENOMEM; -+} -+ -+static void init_defrootdomain(void) -+{ -+ init_rootdomain(&def_root_domain); -+ -+ atomic_set(&def_root_domain.refcount, 1); -+} -+ -+static struct root_domain *alloc_rootdomain(void) -+{ -+ struct root_domain *rd; -+ -+ rd = kmalloc(sizeof(*rd), GFP_KERNEL); -+ if (!rd) -+ return NULL; -+ -+ if (init_rootdomain(rd) != 0) { -+ kfree(rd); -+ return NULL; -+ } -+ -+ return rd; -+} -+ -+static void free_sched_domain(struct rcu_head *rcu) -+{ -+ struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu); -+ -+ kfree(sd); -+} -+ -+static void destroy_sched_domain(struct sched_domain *sd, int cpu) -+{ -+ call_rcu(&sd->rcu, free_sched_domain); -+} -+ -+static void destroy_sched_domains(struct sched_domain *sd, int cpu) -+{ -+ for (; sd; sd = sd->parent) -+ destroy_sched_domain(sd, cpu); -+} -+ -+/* -+ * Attach the domain 'sd' to 'cpu' as its base domain. Callers must -+ * hold the hotplug lock. -+ */ -+static void -+cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) -+{ -+ struct rq *rq = cpu_rq(cpu); -+ struct sched_domain *tmp; -+ -+ /* Remove the sched domains which do not contribute to scheduling. */ -+ for (tmp = sd; tmp; ) { -+ struct sched_domain *parent = tmp->parent; -+ if (!parent) -+ break; -+ -+ if (sd_parent_degenerate(tmp, parent)) { -+ tmp->parent = parent->parent; -+ if (parent->parent) -+ parent->parent->child = tmp; -+ destroy_sched_domain(parent, cpu); -+ } else -+ tmp = tmp->parent; -+ } -+ -+ if (sd && sd_degenerate(sd)) { -+ tmp = sd; -+ sd = sd->parent; -+ destroy_sched_domain(tmp, cpu); -+ if (sd) -+ sd->child = NULL; -+ } -+ -+ sched_domain_debug(sd, cpu); -+ -+ rq_attach_root(rq, rd); -+ tmp = rq->sd; -+ rcu_assign_pointer(rq->sd, sd); -+ destroy_sched_domains(tmp, cpu); -+} -+ -+/* cpus with isolated domains */ -+static cpumask_var_t cpu_isolated_map; -+ -+/* Setup the mask of cpus configured for isolated domains */ -+static int __init isolated_cpu_setup(char *str) -+{ -+ alloc_bootmem_cpumask_var(&cpu_isolated_map); -+ cpulist_parse(str, cpu_isolated_map); -+ return 1; -+} -+ -+__setup("isolcpus=", isolated_cpu_setup); -+ -+static const struct cpumask *cpu_cpu_mask(int cpu) -+{ -+ return cpumask_of_node(cpu_to_node(cpu)); -+} -+ -+struct sd_data { -+ struct sched_domain **__percpu sd; -+}; -+ -+struct s_data { -+ struct sched_domain ** __percpu sd; -+ struct root_domain *rd; -+}; -+ -+enum s_alloc { -+ sa_rootdomain, -+ sa_sd, -+ sa_sd_storage, -+ sa_none, -+}; -+ -+struct sched_domain_topology_level; -+ -+typedef struct sched_domain *(*sched_domain_init_f)(struct sched_domain_topology_level *tl, int cpu); -+typedef const struct cpumask *(*sched_domain_mask_f)(int cpu); -+ -+#define SDTL_OVERLAP 0x01 -+ -+struct sched_domain_topology_level { -+ sched_domain_init_f init; -+ sched_domain_mask_f mask; -+ int flags; -+ int numa_level; -+ struct sd_data data; -+}; -+ -+/* -+ * Initializers for schedule domains -+ * Non-inlined to reduce accumulated stack pressure in build_sched_domains() -+ */ -+ -+#ifdef CONFIG_SCHED_DEBUG -+# define SD_INIT_NAME(sd, type) sd->name = #type -+#else -+# define SD_INIT_NAME(sd, type) do { } while (0) -+#endif -+ -+#define SD_INIT_FUNC(type) \ -+static noinline struct sched_domain * \ -+sd_init_##type(struct sched_domain_topology_level *tl, int cpu) \ -+{ \ -+ struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu); \ -+ *sd = SD_##type##_INIT; \ -+ SD_INIT_NAME(sd, type); \ -+ sd->private = &tl->data; \ -+ return sd; \ -+} -+ -+SD_INIT_FUNC(CPU) -+#ifdef CONFIG_SCHED_SMT -+ SD_INIT_FUNC(SIBLING) -+#endif -+#ifdef CONFIG_SCHED_MC -+ SD_INIT_FUNC(MC) -+#endif -+#ifdef CONFIG_SCHED_BOOK -+ SD_INIT_FUNC(BOOK) -+#endif -+ -+static int default_relax_domain_level = -1; -+int sched_domain_level_max; -+ -+static int __init setup_relax_domain_level(char *str) -+{ -+ if (kstrtoint(str, 0, &default_relax_domain_level)) -+ pr_warn("Unable to set relax_domain_level\n"); -+ -+ return 1; -+} -+__setup("relax_domain_level=", setup_relax_domain_level); -+ -+static void set_domain_attribute(struct sched_domain *sd, -+ struct sched_domain_attr *attr) -+{ -+ int request; -+ -+ if (!attr || attr->relax_domain_level < 0) { -+ if (default_relax_domain_level < 0) -+ return; -+ else -+ request = default_relax_domain_level; -+ } else -+ request = attr->relax_domain_level; -+ if (request < sd->level) { -+ /* turn off idle balance on this domain */ -+ sd->flags &= ~(SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE); -+ } else { -+ /* turn on idle balance on this domain */ -+ sd->flags |= (SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE); -+ } -+} -+ -+static void __sdt_free(const struct cpumask *cpu_map); -+static int __sdt_alloc(const struct cpumask *cpu_map); -+ -+static void __free_domain_allocs(struct s_data *d, enum s_alloc what, -+ const struct cpumask *cpu_map) -+{ -+ switch (what) { -+ case sa_rootdomain: -+ if (!atomic_read(&d->rd->refcount)) -+ free_rootdomain(&d->rd->rcu); /* fall through */ -+ case sa_sd: -+ free_percpu(d->sd); /* fall through */ -+ case sa_sd_storage: -+ __sdt_free(cpu_map); /* fall through */ -+ case sa_none: -+ break; -+ } -+} -+ -+static enum s_alloc __visit_domain_allocation_hell(struct s_data *d, -+ const struct cpumask *cpu_map) -+{ -+ memset(d, 0, sizeof(*d)); -+ -+ if (__sdt_alloc(cpu_map)) -+ return sa_sd_storage; -+ d->sd = alloc_percpu(struct sched_domain *); -+ if (!d->sd) -+ return sa_sd_storage; -+ d->rd = alloc_rootdomain(); -+ if (!d->rd) -+ return sa_sd; -+ return sa_rootdomain; -+} -+ -+/* -+ * NULL the sd_data elements we've used to build the sched_domain -+ * structure so that the subsequent __free_domain_allocs() -+ * will not free the data we're using. -+ */ -+static void claim_allocations(int cpu, struct sched_domain *sd) -+{ -+ struct sd_data *sdd = sd->private; -+ -+ WARN_ON_ONCE(*per_cpu_ptr(sdd->sd, cpu) != sd); -+ *per_cpu_ptr(sdd->sd, cpu) = NULL; -+} -+ -+#ifdef CONFIG_SCHED_SMT -+static const struct cpumask *cpu_smt_mask(int cpu) -+{ -+ return topology_thread_cpumask(cpu); -+} -+#endif -+ -+/* -+ * Topology list, bottom-up. -+ */ -+static struct sched_domain_topology_level default_topology[] = { -+#ifdef CONFIG_SCHED_SMT -+ { sd_init_SIBLING, cpu_smt_mask, }, -+#endif -+#ifdef CONFIG_SCHED_MC -+ { sd_init_MC, cpu_coregroup_mask, }, -+#endif -+#ifdef CONFIG_SCHED_BOOK -+ { sd_init_BOOK, cpu_book_mask, }, -+#endif -+ { sd_init_CPU, cpu_cpu_mask, }, -+ { NULL, }, -+}; -+ -+static struct sched_domain_topology_level *sched_domain_topology = default_topology; -+ -+#ifdef CONFIG_NUMA -+ -+static int sched_domains_numa_levels; -+static int *sched_domains_numa_distance; -+static struct cpumask ***sched_domains_numa_masks; -+static int sched_domains_curr_level; -+ -+static inline int sd_local_flags(int level) -+{ -+ if (sched_domains_numa_distance[level] > RECLAIM_DISTANCE) -+ return 0; -+ -+ return SD_BALANCE_EXEC | SD_BALANCE_FORK | SD_WAKE_AFFINE; -+} -+ -+static struct sched_domain * -+sd_numa_init(struct sched_domain_topology_level *tl, int cpu) -+{ -+ struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu); -+ int level = tl->numa_level; -+ int sd_weight = cpumask_weight( -+ sched_domains_numa_masks[level][cpu_to_node(cpu)]); -+ -+ *sd = (struct sched_domain){ -+ .min_interval = sd_weight, -+ .max_interval = 2*sd_weight, -+ .busy_factor = 32, -+ .imbalance_pct = 125, -+ .cache_nice_tries = 2, -+ .busy_idx = 3, -+ .idle_idx = 2, -+ .newidle_idx = 0, -+ .wake_idx = 0, -+ .forkexec_idx = 0, -+ -+ .flags = 1*SD_LOAD_BALANCE -+ | 1*SD_BALANCE_NEWIDLE -+ | 0*SD_BALANCE_EXEC -+ | 0*SD_BALANCE_FORK -+ | 0*SD_BALANCE_WAKE -+ | 0*SD_WAKE_AFFINE -+ | 0*SD_SHARE_CPUPOWER -+ | 0*SD_SHARE_PKG_RESOURCES -+ | 1*SD_SERIALIZE -+ | 0*SD_PREFER_SIBLING -+ | sd_local_flags(level) -+ , -+ .last_balance = jiffies, -+ .balance_interval = sd_weight, -+ }; -+ SD_INIT_NAME(sd, NUMA); -+ sd->private = &tl->data; -+ -+ /* -+ * Ugly hack to pass state to sd_numa_mask()... -+ */ -+ sched_domains_curr_level = tl->numa_level; -+ -+ return sd; -+} -+ -+static const struct cpumask *sd_numa_mask(int cpu) -+{ -+ return sched_domains_numa_masks[sched_domains_curr_level][cpu_to_node(cpu)]; -+} -+ -+static void sched_numa_warn(const char *str) -+{ -+ static int done = false; -+ int i,j; -+ -+ if (done) -+ return; -+ -+ done = true; -+ -+ printk(KERN_WARNING "ERROR: %s\n\n", str); -+ -+ for (i = 0; i < nr_node_ids; i++) { -+ printk(KERN_WARNING " "); -+ for (j = 0; j < nr_node_ids; j++) -+ printk(KERN_CONT "%02d ", node_distance(i,j)); -+ printk(KERN_CONT "\n"); -+ } -+ printk(KERN_WARNING "\n"); -+} -+ -+static bool find_numa_distance(int distance) -+{ -+ int i; -+ -+ if (distance == node_distance(0, 0)) -+ return true; -+ -+ for (i = 0; i < sched_domains_numa_levels; i++) { -+ if (sched_domains_numa_distance[i] == distance) -+ return true; -+ } -+ -+ return false; -+} -+ -+static void sched_init_numa(void) -+{ -+ int next_distance, curr_distance = node_distance(0, 0); -+ struct sched_domain_topology_level *tl; -+ int level = 0; -+ int i, j, k; -+ -+ sched_domains_numa_distance = kzalloc(sizeof(int) * nr_node_ids, GFP_KERNEL); -+ if (!sched_domains_numa_distance) -+ return; -+ -+ /* -+ * O(nr_nodes^2) deduplicating selection sort -- in order to find the -+ * unique distances in the node_distance() table. -+ * -+ * Assumes node_distance(0,j) includes all distances in -+ * node_distance(i,j) in order to avoid cubic time. -+ */ -+ next_distance = curr_distance; -+ for (i = 0; i < nr_node_ids; i++) { -+ for (j = 0; j < nr_node_ids; j++) { -+ for (k = 0; k < nr_node_ids; k++) { -+ int distance = node_distance(i, k); -+ -+ if (distance > curr_distance && -+ (distance < next_distance || -+ next_distance == curr_distance)) -+ next_distance = distance; -+ -+ /* -+ * While not a strong assumption it would be nice to know -+ * about cases where if node A is connected to B, B is not -+ * equally connected to A. -+ */ -+ if (sched_debug() && node_distance(k, i) != distance) -+ sched_numa_warn("Node-distance not symmetric"); -+ -+ if (sched_debug() && i && !find_numa_distance(distance)) -+ sched_numa_warn("Node-0 not representative"); -+ } -+ if (next_distance != curr_distance) { -+ sched_domains_numa_distance[level++] = next_distance; -+ sched_domains_numa_levels = level; -+ curr_distance = next_distance; -+ } else break; -+ } -+ -+ /* -+ * In case of sched_debug() we verify the above assumption. -+ */ -+ if (!sched_debug()) -+ break; -+ } -+ /* -+ * 'level' contains the number of unique distances, excluding the -+ * identity distance node_distance(i,i). -+ * -+ * The sched_domains_numa_distance[] array includes the actual distance -+ * numbers. -+ */ -+ -+ /* -+ * Here, we should temporarily reset sched_domains_numa_levels to 0. -+ * If it fails to allocate memory for array sched_domains_numa_masks[][], -+ * the array will contain less then 'level' members. This could be -+ * dangerous when we use it to iterate array sched_domains_numa_masks[][] -+ * in other functions. -+ * -+ * We reset it to 'level' at the end of this function. -+ */ -+ sched_domains_numa_levels = 0; -+ -+ sched_domains_numa_masks = kzalloc(sizeof(void *) * level, GFP_KERNEL); -+ if (!sched_domains_numa_masks) -+ return; -+ -+ /* -+ * Now for each level, construct a mask per node which contains all -+ * cpus of nodes that are that many hops away from us. -+ */ -+ for (i = 0; i < level; i++) { -+ sched_domains_numa_masks[i] = -+ kzalloc(nr_node_ids * sizeof(void *), GFP_KERNEL); -+ if (!sched_domains_numa_masks[i]) -+ return; -+ -+ for (j = 0; j < nr_node_ids; j++) { -+ struct cpumask *mask = kzalloc(cpumask_size(), GFP_KERNEL); -+ if (!mask) -+ return; -+ -+ sched_domains_numa_masks[i][j] = mask; -+ -+ for (k = 0; k < nr_node_ids; k++) { -+ if (node_distance(j, k) > sched_domains_numa_distance[i]) -+ continue; -+ -+ cpumask_or(mask, mask, cpumask_of_node(k)); -+ } -+ } -+ } -+ -+ tl = kzalloc((ARRAY_SIZE(default_topology) + level) * -+ sizeof(struct sched_domain_topology_level), GFP_KERNEL); -+ if (!tl) -+ return; -+ -+ /* -+ * Copy the default topology bits.. -+ */ -+ for (i = 0; default_topology[i].init; i++) -+ tl[i] = default_topology[i]; -+ -+ /* -+ * .. and append 'j' levels of NUMA goodness. -+ */ -+ for (j = 0; j < level; i++, j++) { -+ tl[i] = (struct sched_domain_topology_level){ -+ .init = sd_numa_init, -+ .mask = sd_numa_mask, -+ .flags = SDTL_OVERLAP, -+ .numa_level = j, -+ }; -+ } -+ -+ sched_domain_topology = tl; -+ -+ sched_domains_numa_levels = level; -+} -+ -+static void sched_domains_numa_masks_set(int cpu) -+{ -+ int i, j; -+ int node = cpu_to_node(cpu); -+ -+ for (i = 0; i < sched_domains_numa_levels; i++) { -+ for (j = 0; j < nr_node_ids; j++) { -+ if (node_distance(j, node) <= sched_domains_numa_distance[i]) -+ cpumask_set_cpu(cpu, sched_domains_numa_masks[i][j]); -+ } -+ } -+} -+ -+static void sched_domains_numa_masks_clear(int cpu) -+{ -+ int i, j; -+ for (i = 0; i < sched_domains_numa_levels; i++) { -+ for (j = 0; j < nr_node_ids; j++) -+ cpumask_clear_cpu(cpu, sched_domains_numa_masks[i][j]); -+ } -+} -+ -+/* -+ * Update sched_domains_numa_masks[level][node] array when new cpus -+ * are onlined. -+ */ -+static int sched_domains_numa_masks_update(struct notifier_block *nfb, -+ unsigned long action, -+ void *hcpu) -+{ -+ int cpu = (long)hcpu; -+ -+ switch (action & ~CPU_TASKS_FROZEN) { -+ case CPU_ONLINE: -+ sched_domains_numa_masks_set(cpu); -+ break; -+ -+ case CPU_DEAD: -+ sched_domains_numa_masks_clear(cpu); -+ break; -+ -+ default: -+ return NOTIFY_DONE; -+ } -+ -+ return NOTIFY_OK; -+} -+#else -+static inline void sched_init_numa(void) -+{ -+} -+ -+static int sched_domains_numa_masks_update(struct notifier_block *nfb, -+ unsigned long action, -+ void *hcpu) -+{ -+ return 0; -+} -+#endif /* CONFIG_NUMA */ -+ -+static int __sdt_alloc(const struct cpumask *cpu_map) -+{ -+ struct sched_domain_topology_level *tl; -+ int j; -+ -+ for (tl = sched_domain_topology; tl->init; tl++) { -+ struct sd_data *sdd = &tl->data; -+ -+ sdd->sd = alloc_percpu(struct sched_domain *); -+ if (!sdd->sd) -+ return -ENOMEM; -+ -+ for_each_cpu(j, cpu_map) { -+ struct sched_domain *sd; -+ -+ sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(), -+ GFP_KERNEL, cpu_to_node(j)); -+ if (!sd) -+ return -ENOMEM; -+ -+ *per_cpu_ptr(sdd->sd, j) = sd; -+ } -+ } -+ -+ return 0; -+} -+ -+static void __sdt_free(const struct cpumask *cpu_map) -+{ -+ struct sched_domain_topology_level *tl; -+ int j; -+ -+ for (tl = sched_domain_topology; tl->init; tl++) { -+ struct sd_data *sdd = &tl->data; -+ -+ for_each_cpu(j, cpu_map) { -+ struct sched_domain *sd; -+ -+ if (sdd->sd) { -+ sd = *per_cpu_ptr(sdd->sd, j); -+ kfree(*per_cpu_ptr(sdd->sd, j)); -+ } -+ } -+ free_percpu(sdd->sd); -+ sdd->sd = NULL; -+ } -+} -+ -+struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl, -+ struct s_data *d, const struct cpumask *cpu_map, -+ struct sched_domain_attr *attr, struct sched_domain *child, -+ int cpu) -+{ -+ struct sched_domain *sd = tl->init(tl, cpu); -+ if (!sd) -+ return child; -+ -+ cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu)); -+ if (child) { -+ sd->level = child->level + 1; -+ sched_domain_level_max = max(sched_domain_level_max, sd->level); -+ child->parent = sd; -+ } -+ sd->child = child; -+ set_domain_attribute(sd, attr); -+ -+ return sd; -+} -+ -+/* -+ * Build sched domains for a given set of cpus and attach the sched domains -+ * to the individual cpus -+ */ -+static int build_sched_domains(const struct cpumask *cpu_map, -+ struct sched_domain_attr *attr) -+{ -+ enum s_alloc alloc_state = sa_none; -+ struct sched_domain *sd; -+ struct s_data d; -+ int i, ret = -ENOMEM; -+ -+ alloc_state = __visit_domain_allocation_hell(&d, cpu_map); -+ if (alloc_state != sa_rootdomain) -+ goto error; -+ -+ /* Set up domains for cpus specified by the cpu_map. */ -+ for_each_cpu(i, cpu_map) { -+ struct sched_domain_topology_level *tl; -+ -+ sd = NULL; -+ for (tl = sched_domain_topology; tl->init; tl++) { -+ sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); -+ if (tl->flags & SDTL_OVERLAP) -+ sd->flags |= SD_OVERLAP; -+ if (cpumask_equal(cpu_map, sched_domain_span(sd))) -+ break; -+ } -+ -+ while (sd->child) -+ sd = sd->child; -+ -+ *per_cpu_ptr(d.sd, i) = sd; -+ } -+ -+ /* Calculate CPU power for physical packages and nodes */ -+ for (i = nr_cpumask_bits-1; i >= 0; i--) { -+ if (!cpumask_test_cpu(i, cpu_map)) -+ continue; -+ -+ for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { -+ claim_allocations(i, sd); -+ } -+ } -+ -+ /* Attach the domains */ -+ rcu_read_lock(); -+ for_each_cpu(i, cpu_map) { -+ sd = *per_cpu_ptr(d.sd, i); -+ cpu_attach_domain(sd, d.rd, i); -+ } -+ rcu_read_unlock(); -+ -+ ret = 0; -+error: -+ __free_domain_allocs(&d, alloc_state, cpu_map); -+ return ret; -+} -+ -+static cpumask_var_t *doms_cur; /* current sched domains */ -+static int ndoms_cur; /* number of sched domains in 'doms_cur' */ -+static struct sched_domain_attr *dattr_cur; -+ /* attribues of custom domains in 'doms_cur' */ -+ -+/* -+ * Special case: If a kmalloc of a doms_cur partition (array of -+ * cpumask) fails, then fallback to a single sched domain, -+ * as determined by the single cpumask fallback_doms. -+ */ -+static cpumask_var_t fallback_doms; -+ -+/* -+ * arch_update_cpu_topology lets virtualized architectures update the -+ * cpu core maps. It is supposed to return 1 if the topology changed -+ * or 0 if it stayed the same. -+ */ -+int __attribute__((weak)) arch_update_cpu_topology(void) -+{ -+ return 0; -+} -+ -+cpumask_var_t *alloc_sched_domains(unsigned int ndoms) -+{ -+ int i; -+ cpumask_var_t *doms; -+ -+ doms = kmalloc(sizeof(*doms) * ndoms, GFP_KERNEL); -+ if (!doms) -+ return NULL; -+ for (i = 0; i < ndoms; i++) { -+ if (!alloc_cpumask_var(&doms[i], GFP_KERNEL)) { -+ free_sched_domains(doms, i); -+ return NULL; -+ } -+ } -+ return doms; -+} -+ -+void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms) -+{ -+ unsigned int i; -+ for (i = 0; i < ndoms; i++) -+ free_cpumask_var(doms[i]); -+ kfree(doms); -+} -+ -+/* -+ * Set up scheduler domains and groups. Callers must hold the hotplug lock. -+ * For now this just excludes isolated cpus, but could be used to -+ * exclude other special cases in the future. -+ */ -+static int init_sched_domains(const struct cpumask *cpu_map) -+{ -+ int err; -+ -+ arch_update_cpu_topology(); -+ ndoms_cur = 1; -+ doms_cur = alloc_sched_domains(ndoms_cur); -+ if (!doms_cur) -+ doms_cur = &fallback_doms; -+ cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map); -+ err = build_sched_domains(doms_cur[0], NULL); -+ register_sched_domain_sysctl(); -+ -+ return err; -+} -+ -+/* -+ * Detach sched domains from a group of cpus specified in cpu_map -+ * These cpus will now be attached to the NULL domain -+ */ -+static void detach_destroy_domains(const struct cpumask *cpu_map) -+{ -+ int i; -+ -+ rcu_read_lock(); -+ for_each_cpu(i, cpu_map) -+ cpu_attach_domain(NULL, &def_root_domain, i); -+ rcu_read_unlock(); -+} -+ -+/* handle null as "default" */ -+static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur, -+ struct sched_domain_attr *new, int idx_new) -+{ -+ struct sched_domain_attr tmp; -+ -+ /* fast path */ -+ if (!new && !cur) -+ return 1; -+ -+ tmp = SD_ATTR_INIT; -+ return !memcmp(cur ? (cur + idx_cur) : &tmp, -+ new ? (new + idx_new) : &tmp, -+ sizeof(struct sched_domain_attr)); -+} -+ -+/* -+ * Partition sched domains as specified by the 'ndoms_new' -+ * cpumasks in the array doms_new[] of cpumasks. This compares -+ * doms_new[] to the current sched domain partitioning, doms_cur[]. -+ * It destroys each deleted domain and builds each new domain. -+ * -+ * 'doms_new' is an array of cpumask_var_t's of length 'ndoms_new'. -+ * The masks don't intersect (don't overlap.) We should setup one -+ * sched domain for each mask. CPUs not in any of the cpumasks will -+ * not be load balanced. If the same cpumask appears both in the -+ * current 'doms_cur' domains and in the new 'doms_new', we can leave -+ * it as it is. -+ * -+ * The passed in 'doms_new' should be allocated using -+ * alloc_sched_domains. This routine takes ownership of it and will -+ * free_sched_domains it when done with it. If the caller failed the -+ * alloc call, then it can pass in doms_new == NULL && ndoms_new == 1, -+ * and partition_sched_domains() will fallback to the single partition -+ * 'fallback_doms', it also forces the domains to be rebuilt. -+ * -+ * If doms_new == NULL it will be replaced with cpu_online_mask. -+ * ndoms_new == 0 is a special case for destroying existing domains, -+ * and it will not create the default domain. -+ * -+ * Call with hotplug lock held -+ */ -+void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[], -+ struct sched_domain_attr *dattr_new) -+{ -+ int i, j, n; -+ int new_topology; -+ -+ mutex_lock(&sched_domains_mutex); -+ -+ /* always unregister in case we don't destroy any domains */ -+ unregister_sched_domain_sysctl(); -+ -+ /* Let architecture update cpu core mappings. */ -+ new_topology = arch_update_cpu_topology(); -+ -+ n = doms_new ? ndoms_new : 0; -+ -+ /* Destroy deleted domains */ -+ for (i = 0; i < ndoms_cur; i++) { -+ for (j = 0; j < n && !new_topology; j++) { -+ if (cpumask_equal(doms_cur[i], doms_new[j]) -+ && dattrs_equal(dattr_cur, i, dattr_new, j)) -+ goto match1; -+ } -+ /* no match - a current sched domain not in new doms_new[] */ -+ detach_destroy_domains(doms_cur[i]); -+match1: -+ ; -+ } -+ -+ if (doms_new == NULL) { -+ ndoms_cur = 0; -+ doms_new = &fallback_doms; -+ cpumask_andnot(doms_new[0], cpu_active_mask, cpu_isolated_map); -+ WARN_ON_ONCE(dattr_new); -+ } -+ -+ /* Build new domains */ -+ for (i = 0; i < ndoms_new; i++) { -+ for (j = 0; j < ndoms_cur && !new_topology; j++) { -+ if (cpumask_equal(doms_new[i], doms_cur[j]) -+ && dattrs_equal(dattr_new, i, dattr_cur, j)) -+ goto match2; -+ } -+ /* no match - add a new doms_new */ -+ build_sched_domains(doms_new[i], dattr_new ? dattr_new + i : NULL); -+match2: -+ ; -+ } -+ -+ /* Remember the new sched domains */ -+ if (doms_cur != &fallback_doms) -+ free_sched_domains(doms_cur, ndoms_cur); -+ kfree(dattr_cur); /* kfree(NULL) is safe */ -+ doms_cur = doms_new; -+ dattr_cur = dattr_new; -+ ndoms_cur = ndoms_new; -+ -+ register_sched_domain_sysctl(); -+ -+ mutex_unlock(&sched_domains_mutex); -+} -+ -+/* -+ * Update cpusets according to cpu_active mask. If cpusets are -+ * disabled, cpuset_update_active_cpus() becomes a simple wrapper -+ * around partition_sched_domains(). -+ */ -+static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action, -+ void *hcpu) -+{ -+ switch (action & ~CPU_TASKS_FROZEN) { -+ case CPU_ONLINE: -+ case CPU_DOWN_FAILED: -+ cpuset_update_active_cpus(true); -+ return NOTIFY_OK; -+ default: -+ return NOTIFY_DONE; -+ } -+} -+ -+static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action, -+ void *hcpu) -+{ -+ switch (action & ~CPU_TASKS_FROZEN) { -+ case CPU_DOWN_PREPARE: -+ cpuset_update_active_cpus(false); -+ return NOTIFY_OK; -+ default: -+ return NOTIFY_DONE; -+ } -+} -+ -+#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_MC) -+/* -+ * Cheaper version of the below functions in case support for SMT and MC is -+ * compiled in but CPUs have no siblings. -+ */ -+static bool sole_cpu_idle(int cpu) -+{ -+ return rq_idle(cpu_rq(cpu)); -+} -+#endif -+#ifdef CONFIG_SCHED_SMT -+/* All this CPU's SMT siblings are idle */ -+static bool siblings_cpu_idle(int cpu) -+{ -+ return cpumask_subset(&(cpu_rq(cpu)->smt_siblings), -+ &grq.cpu_idle_map); -+} -+#endif -+#ifdef CONFIG_SCHED_MC -+/* All this CPU's shared cache siblings are idle */ -+static bool cache_cpu_idle(int cpu) -+{ -+ return cpumask_subset(&(cpu_rq(cpu)->cache_siblings), -+ &grq.cpu_idle_map); -+} -+#endif -+ -+enum sched_domain_level { -+ SD_LV_NONE = 0, -+ SD_LV_SIBLING, -+ SD_LV_MC, -+ SD_LV_BOOK, -+ SD_LV_CPU, -+ SD_LV_NODE, -+ SD_LV_ALLNODES, -+ SD_LV_MAX -+}; -+ -+void __init sched_init_smp(void) -+{ -+ struct sched_domain *sd; -+ int cpu; -+ -+ cpumask_var_t non_isolated_cpus; -+ -+ alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL); -+ alloc_cpumask_var(&fallback_doms, GFP_KERNEL); -+ -+ sched_init_numa(); -+ -+ get_online_cpus(); -+ mutex_lock(&sched_domains_mutex); -+ init_sched_domains(cpu_active_mask); -+ cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map); -+ if (cpumask_empty(non_isolated_cpus)) -+ cpumask_set_cpu(smp_processor_id(), non_isolated_cpus); -+ mutex_unlock(&sched_domains_mutex); -+ put_online_cpus(); -+ -+ hotcpu_notifier(sched_domains_numa_masks_update, CPU_PRI_SCHED_ACTIVE); -+ hotcpu_notifier(cpuset_cpu_active, CPU_PRI_CPUSET_ACTIVE); -+ hotcpu_notifier(cpuset_cpu_inactive, CPU_PRI_CPUSET_INACTIVE); -+ -+ /* Move init over to a non-isolated CPU */ -+ if (set_cpus_allowed_ptr(current, non_isolated_cpus) < 0) -+ BUG(); -+ free_cpumask_var(non_isolated_cpus); -+ -+ grq_lock_irq(); -+ /* -+ * Set up the relative cache distance of each online cpu from each -+ * other in a simple array for quick lookup. Locality is determined -+ * by the closest sched_domain that CPUs are separated by. CPUs with -+ * shared cache in SMT and MC are treated as local. Separate CPUs -+ * (within the same package or physically) within the same node are -+ * treated as not local. CPUs not even in the same domain (different -+ * nodes) are treated as very distant. -+ */ -+ for_each_online_cpu(cpu) { -+ struct rq *rq = cpu_rq(cpu); -+ -+ mutex_lock(&sched_domains_mutex); -+ for_each_domain(cpu, sd) { -+ int locality, other_cpu; -+ -+#ifdef CONFIG_SCHED_SMT -+ if (sd->level == SD_LV_SIBLING) { -+ for_each_cpu_mask(other_cpu, *sched_domain_span(sd)) -+ cpumask_set_cpu(other_cpu, &rq->smt_siblings); -+ } -+#endif -+#ifdef CONFIG_SCHED_MC -+ if (sd->level == SD_LV_MC) { -+ for_each_cpu_mask(other_cpu, *sched_domain_span(sd)) -+ cpumask_set_cpu(other_cpu, &rq->cache_siblings); -+ } -+#endif -+ if (sd->level <= SD_LV_SIBLING) -+ locality = 1; -+ else if (sd->level <= SD_LV_MC) -+ locality = 2; -+ else if (sd->level <= SD_LV_NODE) -+ locality = 3; -+ else -+ continue; -+ -+ for_each_cpu_mask(other_cpu, *sched_domain_span(sd)) { -+ if (locality < rq->cpu_locality[other_cpu]) -+ rq->cpu_locality[other_cpu] = locality; -+ } -+ } -+ mutex_unlock(&sched_domains_mutex); -+ -+ /* -+ * Each runqueue has its own function in case it doesn't have -+ * siblings of its own allowing mixed topologies. -+ */ -+#ifdef CONFIG_SCHED_SMT -+ if (cpus_weight(rq->smt_siblings) > 1) -+ rq->siblings_idle = siblings_cpu_idle; -+#endif -+#ifdef CONFIG_SCHED_MC -+ if (cpus_weight(rq->cache_siblings) > 1) -+ rq->cache_idle = cache_cpu_idle; -+#endif -+ } -+ grq_unlock_irq(); -+} -+#else -+void __init sched_init_smp(void) -+{ -+} -+#endif /* CONFIG_SMP */ -+ -+unsigned int sysctl_timer_migration = 1; -+ -+int in_sched_functions(unsigned long addr) -+{ -+ return in_lock_functions(addr) || -+ (addr >= (unsigned long)__sched_text_start -+ && addr < (unsigned long)__sched_text_end); -+} -+ -+void __init sched_init(void) -+{ -+ int i; -+ struct rq *rq; -+ -+ prio_ratios[0] = 128; -+ for (i = 1 ; i < PRIO_RANGE ; i++) -+ prio_ratios[i] = prio_ratios[i - 1] * 11 / 10; -+ -+ raw_spin_lock_init(&grq.lock); -+ grq.nr_running = grq.nr_uninterruptible = grq.nr_switches = 0; -+ grq.niffies = 0; -+ grq.last_jiffy = jiffies; -+ raw_spin_lock_init(&grq.iso_lock); -+ grq.iso_ticks = 0; -+ grq.iso_refractory = false; -+ grq.noc = 1; -+#ifdef CONFIG_SMP -+ init_defrootdomain(); -+ grq.qnr = grq.idle_cpus = 0; -+ cpumask_clear(&grq.cpu_idle_map); -+#else -+ uprq = &per_cpu(runqueues, 0); -+#endif -+ for_each_possible_cpu(i) { -+ rq = cpu_rq(i); -+ rq->user_pc = rq->nice_pc = rq->softirq_pc = rq->system_pc = -+ rq->iowait_pc = rq->idle_pc = 0; -+ rq->dither = false; -+#ifdef CONFIG_SMP -+ rq->sticky_task = NULL; -+ rq->last_niffy = 0; -+ rq->sd = NULL; -+ rq->rd = NULL; -+ rq->online = false; -+ rq->cpu = i; -+ rq_attach_root(rq, &def_root_domain); -+#endif -+ atomic_set(&rq->nr_iowait, 0); -+ } -+ -+#ifdef CONFIG_SMP -+ nr_cpu_ids = i; -+ /* -+ * Set the base locality for cpu cache distance calculation to -+ * "distant" (3). Make sure the distance from a CPU to itself is 0. -+ */ -+ for_each_possible_cpu(i) { -+ int j; -+ -+ rq = cpu_rq(i); -+#ifdef CONFIG_SCHED_SMT -+ cpumask_clear(&rq->smt_siblings); -+ cpumask_set_cpu(i, &rq->smt_siblings); -+ rq->siblings_idle = sole_cpu_idle; -+ cpumask_set_cpu(i, &rq->smt_siblings); -+#endif -+#ifdef CONFIG_SCHED_MC -+ cpumask_clear(&rq->cache_siblings); -+ cpumask_set_cpu(i, &rq->cache_siblings); -+ rq->cache_idle = sole_cpu_idle; -+ cpumask_set_cpu(i, &rq->cache_siblings); -+#endif -+ rq->cpu_locality = kmalloc(nr_cpu_ids * sizeof(int *), GFP_ATOMIC); -+ for_each_possible_cpu(j) { -+ if (i == j) -+ rq->cpu_locality[j] = 0; -+ else -+ rq->cpu_locality[j] = 4; -+ } -+ } -+#endif -+ -+ for (i = 0; i < PRIO_LIMIT; i++) -+ INIT_LIST_HEAD(grq.queue + i); -+ /* delimiter for bitsearch */ -+ __set_bit(PRIO_LIMIT, grq.prio_bitmap); -+ -+#ifdef CONFIG_PREEMPT_NOTIFIERS -+ INIT_HLIST_HEAD(&init_task.preempt_notifiers); -+#endif -+ -+#ifdef CONFIG_RT_MUTEXES -+ plist_head_init(&init_task.pi_waiters); -+#endif -+ -+ /* -+ * The boot idle thread does lazy MMU switching as well: -+ */ -+ atomic_inc(&init_mm.mm_count); -+ enter_lazy_tlb(&init_mm, current); -+ -+ /* -+ * Make us the idle thread. Technically, schedule() should not be -+ * called from this thread, however somewhere below it might be, -+ * but because we are the idle thread, we just pick up running again -+ * when this runqueue becomes "idle". -+ */ -+ init_idle(current, smp_processor_id()); -+ -+#ifdef CONFIG_SMP -+ zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT); -+ /* May be allocated at isolcpus cmdline parse time */ -+ if (cpu_isolated_map == NULL) -+ zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT); -+ idle_thread_set_boot_cpu(); -+#endif /* SMP */ -+} -+ -+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP -+static inline int preempt_count_equals(int preempt_offset) -+{ -+ int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth(); -+ -+ return (nested == preempt_offset); -+} -+ -+void __might_sleep(const char *file, int line, int preempt_offset) -+{ -+ static unsigned long prev_jiffy; /* ratelimiting */ -+ -+ rcu_sleep_check(); /* WARN_ON_ONCE() by default, no rate limit reqd. */ -+ if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) || -+ system_state != SYSTEM_RUNNING || oops_in_progress) -+ return; -+ if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy) -+ return; -+ prev_jiffy = jiffies; -+ -+ printk(KERN_ERR -+ "BUG: sleeping function called from invalid context at %s:%d\n", -+ file, line); -+ printk(KERN_ERR -+ "in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n", -+ in_atomic(), irqs_disabled(), -+ current->pid, current->comm); -+ -+ debug_show_held_locks(current); -+ if (irqs_disabled()) -+ print_irqtrace_events(current); -+ dump_stack(); -+} -+EXPORT_SYMBOL(__might_sleep); -+#endif -+ -+#ifdef CONFIG_MAGIC_SYSRQ -+void normalize_rt_tasks(void) -+{ -+ struct task_struct *g, *p; -+ unsigned long flags; -+ struct rq *rq; -+ int queued; -+ -+ read_lock_irqsave(&tasklist_lock, flags); -+ -+ do_each_thread(g, p) { -+ if (!rt_task(p) && !iso_task(p)) -+ continue; -+ -+ raw_spin_lock(&p->pi_lock); -+ rq = __task_grq_lock(p); -+ -+ queued = task_queued(p); -+ if (queued) -+ dequeue_task(p); -+ __setscheduler(p, rq, SCHED_NORMAL, 0); -+ if (queued) { -+ enqueue_task(p); -+ try_preempt(p, rq); -+ } -+ -+ __task_grq_unlock(); -+ raw_spin_unlock(&p->pi_lock); -+ } while_each_thread(g, p); -+ -+ read_unlock_irqrestore(&tasklist_lock, flags); -+} -+#endif /* CONFIG_MAGIC_SYSRQ */ -+ -+#if defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) -+/* -+ * These functions are only useful for the IA64 MCA handling, or kdb. -+ * -+ * They can only be called when the whole system has been -+ * stopped - every CPU needs to be quiescent, and no scheduling -+ * activity can take place. Using them for anything else would -+ * be a serious bug, and as a result, they aren't even visible -+ * under any other configuration. -+ */ -+ -+/** -+ * curr_task - return the current task for a given cpu. -+ * @cpu: the processor in question. -+ * -+ * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED! -+ */ -+struct task_struct *curr_task(int cpu) -+{ -+ return cpu_curr(cpu); -+} -+ -+#endif /* defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) */ -+ -+#ifdef CONFIG_IA64 -+/** -+ * set_curr_task - set the current task for a given cpu. -+ * @cpu: the processor in question. -+ * @p: the task pointer to set. -+ * -+ * Description: This function must only be used when non-maskable interrupts -+ * are serviced on a separate stack. It allows the architecture to switch the -+ * notion of the current task on a cpu in a non-blocking manner. This function -+ * must be called with all CPU's synchronised, and interrupts disabled, the -+ * and caller must save the original value of the current task (see -+ * curr_task() above) and restore that value before reenabling interrupts and -+ * re-starting the system. -+ * -+ * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED! -+ */ -+void set_curr_task(int cpu, struct task_struct *p) -+{ -+ cpu_curr(cpu) = p; -+} -+ -+#endif -+ -+/* -+ * Use precise platform statistics if available: -+ */ -+#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE -+void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st) -+{ -+ *ut = p->utime; -+ *st = p->stime; -+} -+ -+void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st) -+{ -+ struct task_cputime cputime; -+ -+ thread_group_cputime(p, &cputime); -+ -+ *ut = cputime.utime; -+ *st = cputime.stime; -+} -+ -+void vtime_account_system_irqsafe(struct task_struct *tsk) -+{ -+ unsigned long flags; -+ -+ local_irq_save(flags); -+ vtime_account_system(tsk); -+ local_irq_restore(flags); -+} -+EXPORT_SYMBOL_GPL(vtime_account_system_irqsafe); -+ -+#ifndef __ARCH_HAS_VTIME_TASK_SWITCH -+void vtime_task_switch(struct task_struct *prev) -+{ -+ if (is_idle_task(prev)) -+ vtime_account_idle(prev); -+ else -+ vtime_account_system(prev); -+ -+ vtime_account_user(prev); -+ arch_vtime_task_switch(prev); -+} -+#endif -+ -+#else -+/* -+ * Perform (stime * rtime) / total, but avoid multiplication overflow by -+ * losing precision when the numbers are big. -+ */ -+static cputime_t scale_stime(u64 stime, u64 rtime, u64 total) -+{ -+ u64 scaled; -+ -+ for (;;) { -+ /* Make sure "rtime" is the bigger of stime/rtime */ -+ if (stime > rtime) { -+ u64 tmp = rtime; rtime = stime; stime = tmp; -+ } -+ -+ /* Make sure 'total' fits in 32 bits */ -+ if (total >> 32) -+ goto drop_precision; -+ -+ /* Does rtime (and thus stime) fit in 32 bits? */ -+ if (!(rtime >> 32)) -+ break; -+ -+ /* Can we just balance rtime/stime rather than dropping bits? */ -+ if (stime >> 31) -+ goto drop_precision; -+ -+ /* We can grow stime and shrink rtime and try to make them both fit */ -+ stime <<= 1; -+ rtime >>= 1; -+ continue; -+ -+drop_precision: -+ /* We drop from rtime, it has more bits than stime */ -+ rtime >>= 1; -+ total >>= 1; -+ } -+ -+ /* -+ * Make sure gcc understands that this is a 32x32->64 multiply, -+ * followed by a 64/32->64 divide. -+ */ -+ scaled = div_u64((u64) (u32) stime * (u64) (u32) rtime, (u32)total); -+ return (__force cputime_t) scaled; -+} -+ -+/* -+ * Adjust tick based cputime random precision against scheduler -+ * runtime accounting. -+ */ -+static void cputime_adjust(struct task_cputime *curr, -+ struct cputime *prev, -+ cputime_t *ut, cputime_t *st) -+{ -+ cputime_t rtime, stime, utime, total; -+ -+ stime = curr->stime; -+ total = stime + curr->utime; -+ -+ /* -+ * Tick based cputime accounting depend on random scheduling -+ * timeslices of a task to be interrupted or not by the timer. -+ * Depending on these circumstances, the number of these interrupts -+ * may be over or under-optimistic, matching the real user and system -+ * cputime with a variable precision. -+ * -+ * Fix this by scaling these tick based values against the total -+ * runtime accounted by the CFS scheduler. -+ */ -+ rtime = nsecs_to_cputime(curr->sum_exec_runtime); -+ -+ /* -+ * Update userspace visible utime/stime values only if actual execution -+ * time is bigger than already exported. Note that can happen, that we -+ * provided bigger values due to scaling inaccuracy on big numbers. -+ */ -+ if (prev->stime + prev->utime >= rtime) -+ goto out; -+ -+ if (total) { -+ stime = scale_stime((__force u64)stime, -+ (__force u64)rtime, (__force u64)total); -+ utime = rtime - stime; -+ } else { -+ stime = rtime; -+ utime = 0; -+ } -+ -+ /* -+ * If the tick based count grows faster than the scheduler one, -+ * the result of the scaling may go backward. -+ * Let's enforce monotonicity. -+ */ -+ prev->stime = max(prev->stime, stime); -+ prev->utime = max(prev->utime, utime); -+ -+out: -+ *ut = prev->utime; -+ *st = prev->stime; -+} -+ -+void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st) -+{ -+ struct task_cputime cputime = { -+ .sum_exec_runtime = tsk_seruntime(p), -+ }; -+ -+ task_cputime(p, &cputime.utime, &cputime.stime); -+ cputime_adjust(&cputime, &p->prev_cputime, ut, st); -+} -+ -+/* -+ * Must be called with siglock held. -+ */ -+void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st) -+{ -+ struct task_cputime cputime; -+ -+ thread_group_cputime(p, &cputime); -+ cputime_adjust(&cputime, &p->signal->prev_cputime, ut, st); -+} -+#endif -+ -+void __cpuinit init_idle_bootup_task(struct task_struct *idle) -+{} -+ -+#ifdef CONFIG_SCHED_DEBUG -+void proc_sched_show_task(struct task_struct *p, struct seq_file *m) -+{} -+ -+void proc_sched_set_task(struct task_struct *p) -+{} -+#endif -+ -+#ifdef CONFIG_SMP -+#define SCHED_LOAD_SHIFT (10) -+#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT) -+ -+unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu) -+{ -+ return SCHED_LOAD_SCALE; -+} -+ -+unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu) -+{ -+ unsigned long weight = cpumask_weight(sched_domain_span(sd)); -+ unsigned long smt_gain = sd->smt_gain; -+ -+ smt_gain /= weight; -+ -+ return smt_gain; -+} -+#endif -Index: linux-3.10-ck1/include/uapi/linux/sched.h -=================================================================== ---- linux-3.10-ck1.orig/include/uapi/linux/sched.h 2013-07-09 17:28:57.142502083 +1000 -+++ linux-3.10-ck1/include/uapi/linux/sched.h 2013-07-09 17:29:00.843501924 +1000 -@@ -37,8 +37,15 @@ - #define SCHED_FIFO 1 - #define SCHED_RR 2 - #define SCHED_BATCH 3 --/* SCHED_ISO: reserved but not implemented yet */ -+/* SCHED_ISO: Implemented on BFS only */ - #define SCHED_IDLE 5 -+#ifdef CONFIG_SCHED_BFS -+#define SCHED_ISO 4 -+#define SCHED_IDLEPRIO SCHED_IDLE -+#define SCHED_MAX (SCHED_IDLEPRIO) -+#define SCHED_RANGE(policy) ((policy) <= SCHED_MAX) -+#endif -+ - /* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */ - #define SCHED_RESET_ON_FORK 0x40000000 - -Index: linux-3.10-ck1/include/linux/sched/rt.h -=================================================================== ---- linux-3.10-ck1.orig/include/linux/sched/rt.h 2013-07-09 17:28:57.158502083 +1000 -+++ linux-3.10-ck1/include/linux/sched/rt.h 2013-07-09 17:29:00.844501924 +1000 -@@ -14,11 +14,24 @@ - * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO. - */ - -+#ifdef CONFIG_SCHED_BFS -+#define MAX_USER_RT_PRIO 100 -+#define MAX_RT_PRIO (MAX_USER_RT_PRIO + 1) -+#define DEFAULT_PRIO (MAX_RT_PRIO + 20) -+ -+#define PRIO_RANGE (40) -+#define MAX_PRIO (MAX_RT_PRIO + PRIO_RANGE) -+#define ISO_PRIO (MAX_RT_PRIO) -+#define NORMAL_PRIO (MAX_RT_PRIO + 1) -+#define IDLE_PRIO (MAX_RT_PRIO + 2) -+#define PRIO_LIMIT ((IDLE_PRIO) + 1) -+#else /* CONFIG_SCHED_BFS */ - #define MAX_USER_RT_PRIO 100 - #define MAX_RT_PRIO MAX_USER_RT_PRIO - - #define MAX_PRIO (MAX_RT_PRIO + 40) - #define DEFAULT_PRIO (MAX_RT_PRIO + 20) -+#endif /* CONFIG_SCHED_BFS */ - - static inline int rt_prio(int prio) - { -Index: linux-3.10-ck1/kernel/stop_machine.c -=================================================================== ---- linux-3.10-ck1.orig/kernel/stop_machine.c 2013-07-09 17:28:57.177502082 +1000 -+++ linux-3.10-ck1/kernel/stop_machine.c 2013-07-09 17:29:00.844501924 +1000 -@@ -40,7 +40,8 @@ - }; - - static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper); --static DEFINE_PER_CPU(struct task_struct *, cpu_stopper_task); -+DEFINE_PER_CPU(struct task_struct *, cpu_stopper_task); -+ - static bool stop_machine_initialized = false; - - static void cpu_stop_init_done(struct cpu_stop_done *done, unsigned int nr_todo) -Index: linux-3.10-ck1/drivers/cpufreq/cpufreq_conservative.c -=================================================================== ---- linux-3.10-ck1.orig/drivers/cpufreq/cpufreq_conservative.c 2013-07-09 17:28:57.219502080 +1000 -+++ linux-3.10-ck1/drivers/cpufreq/cpufreq_conservative.c 2013-07-09 17:29:00.844501924 +1000 -@@ -27,8 +27,8 @@ - #include "cpufreq_governor.h" - - /* Conservative governor macros */ --#define DEF_FREQUENCY_UP_THRESHOLD (80) --#define DEF_FREQUENCY_DOWN_THRESHOLD (20) -+#define DEF_FREQUENCY_UP_THRESHOLD (63) -+#define DEF_FREQUENCY_DOWN_THRESHOLD (26) - #define DEF_FREQUENCY_STEP (5) - #define DEF_SAMPLING_DOWN_FACTOR (1) - #define MAX_SAMPLING_DOWN_FACTOR (10) -Index: linux-3.10-ck1/kernel/sched/Makefile -=================================================================== ---- linux-3.10-ck1.orig/kernel/sched/Makefile 2013-07-09 17:28:57.194502081 +1000 -+++ linux-3.10-ck1/kernel/sched/Makefile 2013-07-09 17:29:00.844501924 +1000 -@@ -11,9 +11,13 @@ - CFLAGS_core.o := $(PROFILING) -fno-omit-frame-pointer - endif - -+ifdef CONFIG_SCHED_BFS -+obj-y += bfs.o clock.o -+else - obj-y += core.o clock.o cputime.o idle_task.o fair.o rt.o stop_task.o --obj-$(CONFIG_SMP) += cpupri.o - obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o --obj-$(CONFIG_SCHEDSTATS) += stats.o - obj-$(CONFIG_SCHED_DEBUG) += debug.o - obj-$(CONFIG_CGROUP_CPUACCT) += cpuacct.o -+endif -+obj-$(CONFIG_SMP) += cpupri.o -+obj-$(CONFIG_SCHEDSTATS) += stats.o -Index: linux-3.10-ck1/kernel/time/Kconfig -=================================================================== ---- linux-3.10-ck1.orig/kernel/time/Kconfig 2013-07-09 17:28:57.190502081 +1000 -+++ linux-3.10-ck1/kernel/time/Kconfig 2013-07-09 17:29:00.844501924 +1000 -@@ -94,7 +94,7 @@ - config NO_HZ_FULL - bool "Full dynticks system (tickless)" - # NO_HZ_COMMON dependency -- depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS -+ depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS && !SCHED_BFS - # We need at least one periodic CPU for timekeeping - depends on SMP - # RCU_USER_QS dependency -Index: linux-3.10-ck1/kernel/Kconfig.preempt -=================================================================== ---- linux-3.10-ck1.orig/kernel/Kconfig.preempt 2013-07-09 17:28:57.103502085 +1000 -+++ linux-3.10-ck1/kernel/Kconfig.preempt 2013-07-09 17:29:01.081501914 +1000 -@@ -1,7 +1,7 @@ - - choice - prompt "Preemption Model" -- default PREEMPT_NONE -+ default PREEMPT - - config PREEMPT_NONE - bool "No Forced Preemption (Server)" -@@ -17,7 +17,7 @@ - latencies. - - config PREEMPT_VOLUNTARY -- bool "Voluntary Kernel Preemption (Desktop)" -+ bool "Voluntary Kernel Preemption (Nothing)" - help - This option reduces the latency of the kernel by adding more - "explicit preemption points" to the kernel code. These new -@@ -31,7 +31,8 @@ - applications to run more 'smoothly' even when the system is - under load. - -- Select this if you are building a kernel for a desktop system. -+ Select this for no system in particular (choose Preemptible -+ instead on a desktop if you know what's good for you). - - config PREEMPT - bool "Preemptible Kernel (Low-Latency Desktop)" -Index: linux-3.10-ck1/kernel/Kconfig.hz -=================================================================== ---- linux-3.10-ck1.orig/kernel/Kconfig.hz 2013-07-09 17:28:57.088502086 +1000 -+++ linux-3.10-ck1/kernel/Kconfig.hz 2013-07-09 17:29:01.287501905 +1000 -@@ -4,7 +4,7 @@ - - choice - prompt "Timer frequency" -- default HZ_250 -+ default HZ_1000 - help - Allows the configuration of the timer frequency. It is customary - to have the timer interrupt run at 1000 Hz but 100 Hz may be more -@@ -23,13 +23,14 @@ - with lots of processors that may show reduced performance if - too many timer interrupts are occurring. - -- config HZ_250 -+ config HZ_250_NODEFAULT - bool "250 HZ" - help -- 250 Hz is a good compromise choice allowing server performance -- while also showing good interactive responsiveness even -- on SMP and NUMA systems. If you are going to be using NTSC video -- or multimedia, selected 300Hz instead. -+ 250 HZ is a lousy compromise choice allowing server interactivity -+ while also showing desktop throughput and no extra power saving on -+ laptops. No good for anything. -+ -+ Recommend 100 or 1000 instead. - - config HZ_300 - bool "300 HZ" -@@ -43,14 +44,16 @@ - bool "1000 HZ" - help - 1000 Hz is the preferred choice for desktop systems and other -- systems requiring fast interactive responses to events. -+ systems requiring fast interactive responses to events. Laptops -+ can also benefit from this choice without sacrificing battery life -+ if dynticks is also enabled. - - endchoice - - config HZ - int - default 100 if HZ_100 -- default 250 if HZ_250 -+ default 250 if HZ_250_NODEFAULT - default 300 if HZ_300 - default 1000 if HZ_1000 - -Index: linux-3.10-ck1/arch/x86/Kconfig -=================================================================== ---- linux-3.10-ck1.orig/arch/x86/Kconfig 2013-07-09 17:28:57.044502087 +1000 -+++ linux-3.10-ck1/arch/x86/Kconfig 2013-07-09 17:29:01.392501900 +1000 -@@ -1149,7 +1149,7 @@ - endchoice - - choice -- prompt "Memory split" if EXPERT -+ prompt "Memory split" - default VMSPLIT_3G - depends on X86_32 - ---help--- -@@ -1169,17 +1169,17 @@ - option alone! - - config VMSPLIT_3G -- bool "3G/1G user/kernel split" -+ bool "Default 896MB lowmem (3G/1G user/kernel split)" - config VMSPLIT_3G_OPT - depends on !X86_PAE -- bool "3G/1G user/kernel split (for full 1G low memory)" -+ bool "1GB lowmem (3G/1G user/kernel split)" - config VMSPLIT_2G -- bool "2G/2G user/kernel split" -+ bool "2GB lowmem (2G/2G user/kernel split)" - config VMSPLIT_2G_OPT - depends on !X86_PAE -- bool "2G/2G user/kernel split (for full 2G low memory)" -+ bool "2GB lowmem (2G/2G user/kernel split)" - config VMSPLIT_1G -- bool "1G/3G user/kernel split" -+ bool "3GB lowmem (1G/3G user/kernel split)" - endchoice - - config PAGE_OFFSET -Index: linux-3.10-ck1/Makefile -=================================================================== ---- linux-3.10-ck1.orig/Makefile 2013-07-09 17:28:57.029502088 +1000 -+++ linux-3.10-ck1/Makefile 2013-07-09 17:29:01.490501896 +1000 -@@ -10,6 +10,10 @@ - # Comments in this file are targeted only to the developer, do not - # expect to learn how to build the kernel reading this file. - -+CKVERSION = -ck1 -+CKNAME = BFS Powered -+EXTRAVERSION := $(EXTRAVERSION)$(CKVERSION) -+ - # Do not: - # o use make's built-in rules and variables - # (this increases performance and avoids hard-to-debug behaviour); diff --git a/sys-kernel/kogaion-sources/files/desktop/change-default-console-loglevel.patch b/sys-kernel/kogaion-sources/files/desktop/change-default-console-loglevel.patch deleted file mode 100644 index 5f16dee5..00000000 --- a/sys-kernel/kogaion-sources/files/desktop/change-default-console-loglevel.patch +++ /dev/null @@ -1,13 +0,0 @@ -// change-default-console-loglevel.patch -diff -upr linux-3.0.orig/kernel/printk.c linux-3.0/kernel/printk.c ---- linux-3.0.orig/kernel/printk.c 2011-07-22 05:17:23.000000000 +0300 -+++ linux-3.0/kernel/printk.c 2011-07-27 14:43:07.000000000 +0300 -@@ -58,7 +58,7 @@ void asmlinkage __attribute__((weak)) ea - - /* We show everything that is MORE important than this.. */ - #define MINIMUM_CONSOLE_LOGLEVEL 1 /* Minimum loglevel we let people use */ --#define DEFAULT_CONSOLE_LOGLEVEL 7 /* anything MORE serious than KERN_DEBUG */ -+#define DEFAULT_CONSOLE_LOGLEVEL 4 /* anything MORE serious than KERN_WARNING */ - - DECLARE_WAIT_QUEUE_HEAD(log_wait); - diff --git a/sys-kernel/kogaion-sources/files/desktop/criu-no-expert.patch b/sys-kernel/kogaion-sources/files/desktop/criu-no-expert.patch deleted file mode 100644 index b22aa9f5..00000000 --- a/sys-kernel/kogaion-sources/files/desktop/criu-no-expert.patch +++ /dev/null @@ -1,23 +0,0 @@ -// criu-no-expert.patch -diff --git a/init/Kconfig b/init/Kconfig -index be8b7f5..7461760 100644 ---- a/init/Kconfig -+++ b/init/Kconfig -@@ -989,7 +989,7 @@ config DEBUG_BLK_CGROUP - endif # CGROUPS - - config CHECKPOINT_RESTORE -- bool "Checkpoint/restore support" if EXPERT -+ bool "Checkpoint/restore support" - default n - help - Enables additional kernel features in a sake of checkpoint/restore. -@@ -1000,7 +1000,7 @@ config CHECKPOINT_RESTORE - If unsure, say N here. - - menuconfig NAMESPACES -- bool "Namespaces support" if EXPERT -+ bool "Namespaces support" - default !EXPERT - help - Provides the way to make tasks work with different objects using diff --git a/sys-kernel/kogaion-sources/files/desktop/enable_haswell_pstate_driver.patch b/sys-kernel/kogaion-sources/files/desktop/enable_haswell_pstate_driver.patch deleted file mode 100644 index 031f8d2f..00000000 --- a/sys-kernel/kogaion-sources/files/desktop/enable_haswell_pstate_driver.patch +++ /dev/null @@ -1,33 +0,0 @@ -// enable_haswell_pstate_driver.patch ---- linux-3.10/drivers/cpufreq/intel_pstate.c 2013-06-30 18:13:29.000000000 -0400 -+++ linux-3.10.mod/drivers/cpufreq/intel_pstate.c 2013-07-05 03:10:36.164568840 -0400 -@@ -522,6 +522,11 @@ - ICPU(0x2a, default_policy), - ICPU(0x2d, default_policy), - ICPU(0x3a, default_policy), -+ ICPU(0x3a, default_policy), -+ ICPU(0x3c, default_policy), -+ ICPU(0x3f, default_policy), -+ ICPU(0x45, default_policy), -+ ICPU(0x46, default_policy), - {} - }; - MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids); ---- linux-3.10/drivers/cpufreq/Kconfig.x86 2013-06-30 18:13:29.000000000 -0400 -+++ linux-3.10.mod/drivers/cpufreq/Kconfig.x86 2013-07-05 03:13:22.823827792 -0400 -@@ -6,12 +6,12 @@ - bool "Intel P state control" - depends on X86 - help -- This driver provides a P state for Intel core processors. -+ This driver provides a P state for Intel Core processors. - The driver implements an internal governor and will become -- the scaling driver and governor for Sandy bridge processors. -+ the scaling driver and governor for Sandy/Ivy Bridge and Haswell processors. - - When this driver is enabled it will become the perferred -- scaling driver for Sandy bridge processors. -+ scaling driver for Sandy/Ivy Bridge and Haswell processors. - - If in doubt, say N. - diff --git a/sys-kernel/kogaion-sources/files/desktop/set_kogaion_extraversion_in_makefile.patch b/sys-kernel/kogaion-sources/files/desktop/set_kogaion_extraversion_in_makefile.patch deleted file mode 100644 index a20090f8..00000000 --- a/sys-kernel/kogaion-sources/files/desktop/set_kogaion_extraversion_in_makefile.patch +++ /dev/null @@ -1,12 +0,0 @@ -diff -Nur a/Makefile b/Makefile ---- a/Makefile 2014-01-30 20:52:03.849613917 +0200 -+++ b/Makefile 2014-01-30 20:56:12.859500865 +0200 -@@ -10,7 +10,7 @@ - # Comments in this file are targeted only to the developer, do not - # expect to learn how to build the kernel reading this file. - --CKVERSION = -ck1 -+CKVERSION = -kogaion - CKNAME = BFS Powered - EXTRAVERSION := $(EXTRAVERSION)$(CKVERSION) - diff --git a/sys-kernel/kogaion-sources/files/desktop/uksm-0.1.2.2-for-v3.10.patch b/sys-kernel/kogaion-sources/files/desktop/uksm-0.1.2.2-for-v3.10.patch deleted file mode 100644 index f62addd2..00000000 --- a/sys-kernel/kogaion-sources/files/desktop/uksm-0.1.2.2-for-v3.10.patch +++ /dev/null @@ -1,7064 +0,0 @@ -diff --git a/Documentation/vm/00-INDEX b/Documentation/vm/00-INDEX -index 5481c8b..7141876 100644 ---- a/Documentation/vm/00-INDEX -+++ b/Documentation/vm/00-INDEX -@@ -14,6 +14,8 @@ hwpoison.txt - - explains what hwpoison is - ksm.txt - - how to use the Kernel Samepage Merging feature. -+uksm.txt -+ - Introduction to Ultra KSM - locking - - info on how locking and synchronization is done in the Linux vm code. - map_hugetlb.c -diff --git a/Documentation/vm/uksm.txt b/Documentation/vm/uksm.txt -new file mode 100644 -index 0000000..9b2cb51 ---- /dev/null -+++ b/Documentation/vm/uksm.txt -@@ -0,0 +1,57 @@ -+The Ultra Kernel Samepage Merging feature -+---------------------------------------------- -+/* -+ * Ultra KSM. Copyright (C) 2011-2012 Nai Xia -+ * -+ * This is an improvement upon KSM. Some basic data structures and routines -+ * are borrowed from ksm.c . -+ * -+ * Its new features: -+ * 1. Full system scan: -+ * It automatically scans all user processes' anonymous VMAs. Kernel-user -+ * interaction to submit a memory area to KSM is no longer needed. -+ * -+ * 2. Rich area detection: -+ * It automatically detects rich areas containing abundant duplicated -+ * pages based. Rich areas are given a full scan speed. Poor areas are -+ * sampled at a reasonable speed with very low CPU consumption. -+ * -+ * 3. Ultra Per-page scan speed improvement: -+ * A new hash algorithm is proposed. As a result, on a machine with -+ * Core(TM)2 Quad Q9300 CPU in 32-bit mode and 800MHZ DDR2 main memory, it -+ * can scan memory areas that does not contain duplicated pages at speed of -+ * 627MB/sec ~ 2445MB/sec and can merge duplicated areas at speed of -+ * 477MB/sec ~ 923MB/sec. -+ * -+ * 4. Thrashing area avoidance: -+ * Thrashing area(an VMA that has frequent Ksm page break-out) can be -+ * filtered out. My benchmark shows it's more efficient than KSM's per-page -+ * hash value based volatile page detection. -+ * -+ * -+ * 5. Misc changes upon KSM: -+ * * It has a fully x86-opitmized memcmp dedicated for 4-byte-aligned page -+ * comparison. It's much faster than default C version on x86. -+ * * rmap_item now has an struct *page member to loosely cache a -+ * address-->page mapping, which reduces too much time-costly -+ * follow_page(). -+ * * The VMA creation/exit procedures are hooked to let the Ultra KSM know. -+ * * try_to_merge_two_pages() now can revert a pte if it fails. No break_ -+ * ksm is needed for this case. -+ * -+ * 6. Full Zero Page consideration(contributed by Figo Zhang) -+ * Now uksmd consider full zero pages as special pages and merge them to an -+ * special unswappable uksm zero page. -+ */ -+ -+ChangeLog: -+ -+2012-05-05 The creation of this Doc -+2012-05-08 UKSM 0.1.1.1 libc crash bug fix, api clean up, doc clean up. -+2012-05-28 UKSM 0.1.1.2 bug fix release -+2012-06-26 UKSM 0.1.2-beta1 first beta release for 0.1.2 -+2012-07-2 UKSM 0.1.2-beta2 -+2012-07-10 UKSM 0.1.2-beta3 -+2012-07-26 UKSM 0.1.2 Fine grained speed control, more scan optimization. -+2012-10-13 UKSM 0.1.2.1 Bug fixes. -+2012-12-31 UKSM 0.1.2.2 Minor bug fixes -diff --git a/fs/exec.c b/fs/exec.c -index ffd7a81..1c4d7d3 100644 ---- a/fs/exec.c -+++ b/fs/exec.c -@@ -19,7 +19,7 @@ - * current->executable is only used by the procfs. This allows a dispatch - * table to check for several different types of binary formats. We keep - * trying until we recognize the file or we run out of supported binary -- * formats. -+ * formats. - */ - - #include -@@ -55,6 +55,7 @@ - #include - #include - #include -+#include - - #include - #include -@@ -1139,7 +1140,7 @@ void setup_new_exec(struct linux_binprm * bprm) - group */ - - current->self_exec_id++; -- -+ - flush_signal_handlers(current, 0); - do_close_on_exec(current->files); - } -@@ -1265,8 +1266,8 @@ static int check_unsafe_exec(struct linux_binprm *bprm) - return res; - } - --/* -- * Fill the binprm structure from the inode. -+/* -+ * Fill the binprm structure from the inode. - * Check permissions, then read the first 128 (BINPRM_BUF_SIZE) bytes - * - * This may be called multiple times for binary chains (scripts for example). -diff --git a/fs/proc/meminfo.c b/fs/proc/meminfo.c -index 5aa847a..c6c5553 100644 ---- a/fs/proc/meminfo.c -+++ b/fs/proc/meminfo.c -@@ -88,6 +88,9 @@ static int meminfo_proc_show(struct seq_file *m, void *v) - "SUnreclaim: %8lu kB\n" - "KernelStack: %8lu kB\n" - "PageTables: %8lu kB\n" -+#ifdef CONFIG_UKSM -+ "KsmZeroPages: %8lu kB\n" -+#endif - #ifdef CONFIG_QUICKLIST - "Quicklists: %8lu kB\n" - #endif -@@ -147,6 +150,9 @@ static int meminfo_proc_show(struct seq_file *m, void *v) - K(global_page_state(NR_SLAB_UNRECLAIMABLE)), - global_page_state(NR_KERNEL_STACK) * THREAD_SIZE / 1024, - K(global_page_state(NR_PAGETABLE)), -+#ifdef CONFIG_UKSM -+ K(global_page_state(NR_UKSM_ZERO_PAGES)), -+#endif - #ifdef CONFIG_QUICKLIST - K(quicklist_total_size()), - #endif -diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h -index a59ff51..df359cc 100644 ---- a/include/asm-generic/pgtable.h -+++ b/include/asm-generic/pgtable.h -@@ -453,12 +453,25 @@ extern void untrack_pfn(struct vm_area_struct *vma, unsigned long pfn, - unsigned long size); - #endif - -+#ifdef CONFIG_UKSM -+static inline int is_uksm_zero_pfn(unsigned long pfn) -+{ -+ extern unsigned long uksm_zero_pfn; -+ return pfn == uksm_zero_pfn; -+} -+#else -+static inline int is_uksm_zero_pfn(unsigned long pfn) -+{ -+ return 0; -+} -+#endif -+ - #ifdef __HAVE_COLOR_ZERO_PAGE - static inline int is_zero_pfn(unsigned long pfn) - { - extern unsigned long zero_pfn; - unsigned long offset_from_zero_pfn = pfn - zero_pfn; -- return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT); -+ return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT) || is_uksm_zero_pfn(pfn); - } - - #define my_zero_pfn(addr) page_to_pfn(ZERO_PAGE(addr)) -@@ -467,7 +480,7 @@ static inline int is_zero_pfn(unsigned long pfn) - static inline int is_zero_pfn(unsigned long pfn) - { - extern unsigned long zero_pfn; -- return pfn == zero_pfn; -+ return (pfn == zero_pfn) || (is_uksm_zero_pfn(pfn)); - } - - static inline unsigned long my_zero_pfn(unsigned long addr) -diff --git a/include/linux/ksm.h b/include/linux/ksm.h -index 45c9b6a..c7de7a7 100644 ---- a/include/linux/ksm.h -+++ b/include/linux/ksm.h -@@ -19,21 +19,6 @@ struct mem_cgroup; - #ifdef CONFIG_KSM - int ksm_madvise(struct vm_area_struct *vma, unsigned long start, - unsigned long end, int advice, unsigned long *vm_flags); --int __ksm_enter(struct mm_struct *mm); --void __ksm_exit(struct mm_struct *mm); -- --static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) --{ -- if (test_bit(MMF_VM_MERGEABLE, &oldmm->flags)) -- return __ksm_enter(mm); -- return 0; --} -- --static inline void ksm_exit(struct mm_struct *mm) --{ -- if (test_bit(MMF_VM_MERGEABLE, &mm->flags)) -- __ksm_exit(mm); --} - - /* - * A KSM page is one of those write-protected "shared pages" or "merged pages" -@@ -80,6 +65,33 @@ int rmap_walk_ksm(struct page *page, int (*rmap_one)(struct page *, - struct vm_area_struct *, unsigned long, void *), void *arg); - void ksm_migrate_page(struct page *newpage, struct page *oldpage); - -+#ifdef CONFIG_KSM_LEGACY -+int __ksm_enter(struct mm_struct *mm); -+void __ksm_exit(struct mm_struct *mm); -+static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) -+{ -+ if (test_bit(MMF_VM_MERGEABLE, &oldmm->flags)) -+ return __ksm_enter(mm); -+ return 0; -+} -+ -+static inline void ksm_exit(struct mm_struct *mm) -+{ -+ if (test_bit(MMF_VM_MERGEABLE, &mm->flags)) -+ __ksm_exit(mm); -+} -+ -+#elif defined(CONFIG_UKSM) -+static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) -+{ -+ return 0; -+} -+ -+static inline void ksm_exit(struct mm_struct *mm) -+{ -+} -+#endif /* !CONFIG_UKSM */ -+ - #else /* !CONFIG_KSM */ - - static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) -@@ -132,4 +144,6 @@ static inline void ksm_migrate_page(struct page *newpage, struct page *oldpage) - #endif /* CONFIG_MMU */ - #endif /* !CONFIG_KSM */ - -+#include -+ - #endif /* __LINUX_KSM_H */ -diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h -index ace9a5f..6a76d6e 100644 ---- a/include/linux/mm_types.h -+++ b/include/linux/mm_types.h -@@ -289,6 +289,9 @@ struct vm_area_struct { - #ifdef CONFIG_NUMA - struct mempolicy *vm_policy; /* NUMA policy for the VMA */ - #endif -+#ifdef CONFIG_UKSM -+ struct vma_slot *uksm_vma_slot; -+#endif - }; - - struct core_thread { -diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h -index 5c76737..a631b29 100644 ---- a/include/linux/mmzone.h -+++ b/include/linux/mmzone.h -@@ -143,6 +143,9 @@ enum zone_stat_item { - #endif - NR_ANON_TRANSPARENT_HUGEPAGES, - NR_FREE_CMA_PAGES, -+#ifdef CONFIG_UKSM -+ NR_UKSM_ZERO_PAGES, -+#endif - NR_VM_ZONE_STAT_ITEMS }; - - /* -@@ -849,7 +852,7 @@ static inline int is_normal_idx(enum zone_type idx) - } - - /** -- * is_highmem - helper function to quickly check if a struct zone is a -+ * is_highmem - helper function to quickly check if a struct zone is a - * highmem zone or not. This is an attempt to keep references - * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum. - * @zone - pointer to struct zone variable -diff --git a/include/linux/sradix-tree.h b/include/linux/sradix-tree.h -new file mode 100644 -index 0000000..6780fdb ---- /dev/null -+++ b/include/linux/sradix-tree.h -@@ -0,0 +1,77 @@ -+#ifndef _LINUX_SRADIX_TREE_H -+#define _LINUX_SRADIX_TREE_H -+ -+ -+#define INIT_SRADIX_TREE(root, mask) \ -+do { \ -+ (root)->height = 0; \ -+ (root)->gfp_mask = (mask); \ -+ (root)->rnode = NULL; \ -+} while (0) -+ -+#define ULONG_BITS (sizeof(unsigned long) * 8) -+#define SRADIX_TREE_INDEX_BITS (8 /* CHAR_BIT */ * sizeof(unsigned long)) -+//#define SRADIX_TREE_MAP_SHIFT 6 -+//#define SRADIX_TREE_MAP_SIZE (1UL << SRADIX_TREE_MAP_SHIFT) -+//#define SRADIX_TREE_MAP_MASK (SRADIX_TREE_MAP_SIZE-1) -+ -+struct sradix_tree_node { -+ unsigned int height; /* Height from the bottom */ -+ unsigned int count; -+ unsigned int fulls; /* Number of full sublevel trees */ -+ struct sradix_tree_node *parent; -+ void *stores[0]; -+}; -+ -+/* A simple radix tree implementation */ -+struct sradix_tree_root { -+ unsigned int height; -+ struct sradix_tree_node *rnode; -+ -+ /* Where found to have available empty stores in its sublevels */ -+ struct sradix_tree_node *enter_node; -+ unsigned int shift; -+ unsigned int stores_size; -+ unsigned int mask; -+ unsigned long min; /* The first hole index */ -+ unsigned long num; -+ //unsigned long *height_to_maxindex; -+ -+ /* How the node is allocated and freed. */ -+ struct sradix_tree_node *(*alloc)(void); -+ void (*free)(struct sradix_tree_node *node); -+ -+ /* When a new node is added and removed */ -+ void (*extend)(struct sradix_tree_node *parent, struct sradix_tree_node *child); -+ void (*assign)(struct sradix_tree_node *node, unsigned index, void *item); -+ void (*rm)(struct sradix_tree_node *node, unsigned offset); -+}; -+ -+struct sradix_tree_path { -+ struct sradix_tree_node *node; -+ int offset; -+}; -+ -+static inline -+void init_sradix_tree_root(struct sradix_tree_root *root, unsigned long shift) -+{ -+ root->height = 0; -+ root->rnode = NULL; -+ root->shift = shift; -+ root->stores_size = 1UL << shift; -+ root->mask = root->stores_size - 1; -+} -+ -+ -+extern void *sradix_tree_next(struct sradix_tree_root *root, -+ struct sradix_tree_node *node, unsigned long index, -+ int (*iter)(void *, unsigned long)); -+ -+extern int sradix_tree_enter(struct sradix_tree_root *root, void **item, int num); -+ -+extern void sradix_tree_delete_from_leaf(struct sradix_tree_root *root, -+ struct sradix_tree_node *node, unsigned long index); -+ -+extern void *sradix_tree_lookup(struct sradix_tree_root *root, unsigned long index); -+ -+#endif /* _LINUX_SRADIX_TREE_H */ -diff --git a/include/linux/uksm.h b/include/linux/uksm.h -new file mode 100644 -index 0000000..a644bca ---- /dev/null -+++ b/include/linux/uksm.h -@@ -0,0 +1,146 @@ -+#ifndef __LINUX_UKSM_H -+#define __LINUX_UKSM_H -+/* -+ * Memory merging support. -+ * -+ * This code enables dynamic sharing of identical pages found in different -+ * memory areas, even if they are not shared by fork(). -+ */ -+ -+/* if !CONFIG_UKSM this file should not be compiled at all. */ -+#ifdef CONFIG_UKSM -+ -+#include -+#include -+#include -+#include -+#include -+ -+extern unsigned long zero_pfn __read_mostly; -+extern unsigned long uksm_zero_pfn __read_mostly; -+extern struct page *empty_uksm_zero_page; -+ -+/* must be done before linked to mm */ -+extern void uksm_vma_add_new(struct vm_area_struct *vma); -+extern void uksm_remove_vma(struct vm_area_struct *vma); -+ -+#define UKSM_SLOT_NEED_SORT (1 << 0) -+#define UKSM_SLOT_NEED_RERAND (1 << 1) -+#define UKSM_SLOT_SCANNED (1 << 2) /* It's scanned in this round */ -+#define UKSM_SLOT_FUL_SCANNED (1 << 3) -+#define UKSM_SLOT_IN_UKSM (1 << 4) -+ -+struct vma_slot { -+ struct sradix_tree_node *snode; -+ unsigned long sindex; -+ -+ struct list_head slot_list; -+ unsigned long fully_scanned_round; -+ unsigned long dedup_num; -+ unsigned long pages_scanned; -+ unsigned long last_scanned; -+ unsigned long pages_to_scan; -+ struct scan_rung *rung; -+ struct page **rmap_list_pool; -+ unsigned int *pool_counts; -+ unsigned long pool_size; -+ struct vm_area_struct *vma; -+ struct mm_struct *mm; -+ unsigned long ctime_j; -+ unsigned long pages; -+ unsigned long flags; -+ unsigned long pages_cowed; /* pages cowed this round */ -+ unsigned long pages_merged; /* pages merged this round */ -+ unsigned long pages_bemerged; -+ -+ /* when it has page merged in this eval round */ -+ struct list_head dedup_list; -+}; -+ -+static inline void uksm_unmap_zero_page(pte_t pte) -+{ -+ if (pte_pfn(pte) == uksm_zero_pfn) -+ __dec_zone_page_state(empty_uksm_zero_page, NR_UKSM_ZERO_PAGES); -+} -+ -+static inline void uksm_map_zero_page(pte_t pte) -+{ -+ if (pte_pfn(pte) == uksm_zero_pfn) -+ __inc_zone_page_state(empty_uksm_zero_page, NR_UKSM_ZERO_PAGES); -+} -+ -+static inline void uksm_cow_page(struct vm_area_struct *vma, struct page *page) -+{ -+ if (vma->uksm_vma_slot && PageKsm(page)) -+ vma->uksm_vma_slot->pages_cowed++; -+} -+ -+static inline void uksm_cow_pte(struct vm_area_struct *vma, pte_t pte) -+{ -+ if (vma->uksm_vma_slot && pte_pfn(pte) == uksm_zero_pfn) -+ vma->uksm_vma_slot->pages_cowed++; -+} -+ -+static inline int uksm_flags_can_scan(unsigned long vm_flags) -+{ -+#ifndef VM_SAO -+#define VM_SAO 0 -+#endif -+ return !(vm_flags & (VM_PFNMAP | VM_IO | VM_DONTEXPAND | -+ VM_HUGETLB | VM_NONLINEAR | VM_MIXEDMAP | -+ VM_SHARED | VM_MAYSHARE | VM_GROWSUP | VM_GROWSDOWN | VM_SAO)); -+} -+ -+static inline void uksm_vm_flags_mod(unsigned long *vm_flags_p) -+{ -+ if (uksm_flags_can_scan(*vm_flags_p)) -+ *vm_flags_p |= VM_MERGEABLE; -+} -+ -+/* -+ * Just a wrapper for BUG_ON for where ksm_zeropage must not be. TODO: it will -+ * be removed when uksm zero page patch is stable enough. -+ */ -+static inline void uksm_bugon_zeropage(pte_t pte) -+{ -+ BUG_ON(pte_pfn(pte) == uksm_zero_pfn); -+} -+#else -+static inline void uksm_vma_add_new(struct vm_area_struct *vma) -+{ -+} -+ -+static inline void uksm_remove_vma(struct vm_area_struct *vma) -+{ -+} -+ -+static inline void uksm_unmap_zero_page(pte_t pte) -+{ -+} -+ -+static inline void uksm_map_zero_page(pte_t pte) -+{ -+} -+ -+static inline void uksm_cow_page(struct vm_area_struct *vma, struct page *page) -+{ -+} -+ -+static inline void uksm_cow_pte(struct vm_area_struct *vma, pte_t pte) -+{ -+} -+ -+static inline int uksm_flags_can_scan(unsigned long vm_flags) -+{ -+ return 0; -+} -+ -+static inline void uksm_vm_flags_mod(unsigned long *vm_flags_p) -+{ -+} -+ -+static inline void uksm_bugon_zeropage(pte_t pte) -+{ -+} -+#endif /* !CONFIG_UKSM */ -+#endif /* __LINUX_UKSM_H */ -diff --git a/kernel/fork.c b/kernel/fork.c -index 987b28a..3e89974 100644 ---- a/kernel/fork.c -+++ b/kernel/fork.c -@@ -397,7 +397,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) - goto fail_nomem; - charge = len; - } -- tmp = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL); -+ tmp = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL); - if (!tmp) - goto fail_nomem; - *tmp = *mpnt; -@@ -454,7 +454,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) - __vma_link_rb(mm, tmp, rb_link, rb_parent); - rb_link = &tmp->vm_rb.rb_right; - rb_parent = &tmp->vm_rb; -- -+ uksm_vma_add_new(tmp); - mm->map_count++; - retval = copy_page_range(mm, oldmm, mpnt); - -diff --git a/lib/Makefile b/lib/Makefile -index c55a037..fcf7e6d 100644 ---- a/lib/Makefile -+++ b/lib/Makefile -@@ -8,7 +8,7 @@ KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS)) - endif - - lib-y := ctype.o string.o vsprintf.o cmdline.o \ -- rbtree.o radix-tree.o dump_stack.o timerqueue.o\ -+ rbtree.o radix-tree.o sradix-tree.o dump_stack.o timerqueue.o\ - idr.o int_sqrt.o extable.o \ - sha1.o md5.o irq_regs.o reciprocal_div.o argv_split.o \ - proportions.o flex_proportions.o prio_heap.o ratelimit.o show_mem.o \ -diff --git a/lib/sradix-tree.c b/lib/sradix-tree.c -new file mode 100644 -index 0000000..8d06329 ---- /dev/null -+++ b/lib/sradix-tree.c -@@ -0,0 +1,476 @@ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+static inline int sradix_node_full(struct sradix_tree_root *root, struct sradix_tree_node *node) -+{ -+ return node->fulls == root->stores_size || -+ (node->height == 1 && node->count == root->stores_size); -+} -+ -+/* -+ * Extend a sradix tree so it can store key @index. -+ */ -+static int sradix_tree_extend(struct sradix_tree_root *root, unsigned long index) -+{ -+ struct sradix_tree_node *node; -+ unsigned int height; -+ -+ if (unlikely(root->rnode == NULL)) { -+ if (!(node = root->alloc())) -+ return -ENOMEM; -+ -+ node->height = 1; -+ root->rnode = node; -+ root->height = 1; -+ } -+ -+ /* Figure out what the height should be. */ -+ height = root->height; -+ index >>= root->shift * height; -+ -+ while (index) { -+ index >>= root->shift; -+ height++; -+ } -+ -+ while (height > root->height) { -+ unsigned int newheight; -+ if (!(node = root->alloc())) -+ return -ENOMEM; -+ -+ /* Increase the height. */ -+ node->stores[0] = root->rnode; -+ root->rnode->parent = node; -+ if (root->extend) -+ root->extend(node, root->rnode); -+ -+ newheight = root->height + 1; -+ node->height = newheight; -+ node->count = 1; -+ if (sradix_node_full(root, root->rnode)) -+ node->fulls = 1; -+ -+ root->rnode = node; -+ root->height = newheight; -+ } -+ -+ return 0; -+} -+ -+/* -+ * Search the next item from the current node, that is not NULL -+ * and can satify root->iter(). -+ */ -+void *sradix_tree_next(struct sradix_tree_root *root, -+ struct sradix_tree_node *node, unsigned long index, -+ int (*iter)(void *item, unsigned long height)) -+{ -+ unsigned long offset; -+ void *item; -+ -+ if (unlikely(node == NULL)) { -+ node = root->rnode; -+ for (offset = 0; offset < root->stores_size; offset++) { -+ item = node->stores[offset]; -+ if (item && (!iter || iter(item, node->height))) -+ break; -+ } -+ -+ if (unlikely(offset >= root->stores_size)) -+ return NULL; -+ -+ if (node->height == 1) -+ return item; -+ else -+ goto go_down; -+ } -+ -+ while (node) { -+ offset = (index & root->mask) + 1; -+ for (;offset < root->stores_size; offset++) { -+ item = node->stores[offset]; -+ if (item && (!iter || iter(item, node->height))) -+ break; -+ } -+ -+ if (offset < root->stores_size) -+ break; -+ -+ node = node->parent; -+ index >>= root->shift; -+ } -+ -+ if (!node) -+ return NULL; -+ -+ while (node->height > 1) { -+go_down: -+ node = item; -+ for (offset = 0; offset < root->stores_size; offset++) { -+ item = node->stores[offset]; -+ if (item && (!iter || iter(item, node->height))) -+ break; -+ } -+ -+ if (unlikely(offset >= root->stores_size)) -+ return NULL; -+ } -+ -+ BUG_ON(offset > root->stores_size); -+ -+ return item; -+} -+ -+/* -+ * Blindly insert the item to the tree. Typically, we reuse the -+ * first empty store item. -+ */ -+int sradix_tree_enter(struct sradix_tree_root *root, void **item, int num) -+{ -+ unsigned long index; -+ unsigned int height; -+ struct sradix_tree_node *node, *tmp = NULL; -+ int offset, offset_saved; -+ void **store = NULL; -+ int error, i, j, shift; -+ -+go_on: -+ index = root->min; -+ -+ if (root->enter_node && !sradix_node_full(root, root->enter_node)) { -+ node = root->enter_node; -+ BUG_ON((index >> (root->shift * root->height))); -+ } else { -+ node = root->rnode; -+ if (node == NULL || (index >> (root->shift * root->height)) -+ || sradix_node_full(root, node)) { -+ error = sradix_tree_extend(root, index); -+ if (error) -+ return error; -+ -+ node = root->rnode; -+ } -+ } -+ -+ -+ height = node->height; -+ shift = (height - 1) * root->shift; -+ offset = (index >> shift) & root->mask; -+ while (shift > 0) { -+ offset_saved = offset; -+ for (; offset < root->stores_size; offset++) { -+ store = &node->stores[offset]; -+ tmp = *store; -+ -+ if (!tmp || !sradix_node_full(root, tmp)) -+ break; -+ } -+ BUG_ON(offset >= root->stores_size); -+ -+ if (offset != offset_saved) { -+ index += (offset - offset_saved) << shift; -+ index &= ~((1UL << shift) - 1); -+ } -+ -+ if (!tmp) { -+ if (!(tmp = root->alloc())) -+ return -ENOMEM; -+ -+ tmp->height = shift / root->shift; -+ *store = tmp; -+ tmp->parent = node; -+ node->count++; -+// if (root->extend) -+// root->extend(node, tmp); -+ } -+ -+ node = tmp; -+ shift -= root->shift; -+ offset = (index >> shift) & root->mask; -+ } -+ -+ BUG_ON(node->height != 1); -+ -+ -+ store = &node->stores[offset]; -+ for (i = 0, j = 0; -+ j < root->stores_size - node->count && -+ i < root->stores_size - offset && j < num; i++) { -+ if (!store[i]) { -+ store[i] = item[j]; -+ if (root->assign) -+ root->assign(node, index + i, item[j]); -+ j++; -+ } -+ } -+ -+ node->count += j; -+ root->num += j; -+ num -= j; -+ -+ while (sradix_node_full(root, node)) { -+ node = node->parent; -+ if (!node) -+ break; -+ -+ node->fulls++; -+ } -+ -+ if (unlikely(!node)) { -+ /* All nodes are full */ -+ root->min = 1 << (root->height * root->shift); -+ root->enter_node = NULL; -+ } else { -+ root->min = index + i - 1; -+ root->min |= (1UL << (node->height - 1)) - 1; -+ root->min++; -+ root->enter_node = node; -+ } -+ -+ if (num) { -+ item += j; -+ goto go_on; -+ } -+ -+ return 0; -+} -+ -+ -+/** -+ * sradix_tree_shrink - shrink height of a sradix tree to minimal -+ * @root sradix tree root -+ * -+ */ -+static inline void sradix_tree_shrink(struct sradix_tree_root *root) -+{ -+ /* try to shrink tree height */ -+ while (root->height > 1) { -+ struct sradix_tree_node *to_free = root->rnode; -+ -+ /* -+ * The candidate node has more than one child, or its child -+ * is not at the leftmost store, we cannot shrink. -+ */ -+ if (to_free->count != 1 || !to_free->stores[0]) -+ break; -+ -+ root->rnode = to_free->stores[0]; -+ root->rnode->parent = NULL; -+ root->height--; -+ if (unlikely(root->enter_node == to_free)) { -+ root->enter_node = NULL; -+ } -+ root->free(to_free); -+ } -+} -+ -+/* -+ * Del the item on the known leaf node and index -+ */ -+void sradix_tree_delete_from_leaf(struct sradix_tree_root *root, -+ struct sradix_tree_node *node, unsigned long index) -+{ -+ unsigned int offset; -+ struct sradix_tree_node *start, *end; -+ -+ BUG_ON(node->height != 1); -+ -+ start = node; -+ while (node && !(--node->count)) -+ node = node->parent; -+ -+ end = node; -+ if (!node) { -+ root->rnode = NULL; -+ root->height = 0; -+ root->min = 0; -+ root->num = 0; -+ root->enter_node = NULL; -+ } else { -+ offset = (index >> (root->shift * (node->height - 1))) & root->mask; -+ if (root->rm) -+ root->rm(node, offset); -+ node->stores[offset] = NULL; -+ root->num--; -+ if (root->min > index) { -+ root->min = index; -+ root->enter_node = node; -+ } -+ } -+ -+ if (start != end) { -+ do { -+ node = start; -+ start = start->parent; -+ if (unlikely(root->enter_node == node)) -+ root->enter_node = end; -+ root->free(node); -+ } while (start != end); -+ -+ /* -+ * Note that shrink may free "end", so enter_node still need to -+ * be checked inside. -+ */ -+ sradix_tree_shrink(root); -+ } else if (node->count == root->stores_size - 1) { -+ /* It WAS a full leaf node. Update the ancestors */ -+ node = node->parent; -+ while (node) { -+ node->fulls--; -+ if (node->fulls != root->stores_size - 1) -+ break; -+ -+ node = node->parent; -+ } -+ } -+} -+ -+void *sradix_tree_lookup(struct sradix_tree_root *root, unsigned long index) -+{ -+ unsigned int height, offset; -+ struct sradix_tree_node *node; -+ int shift; -+ -+ node = root->rnode; -+ if (node == NULL || (index >> (root->shift * root->height))) -+ return NULL; -+ -+ height = root->height; -+ shift = (height - 1) * root->shift; -+ -+ do { -+ offset = (index >> shift) & root->mask; -+ node = node->stores[offset]; -+ if (!node) -+ return NULL; -+ -+ shift -= root->shift; -+ } while (shift >= 0); -+ -+ return node; -+} -+ -+/* -+ * Return the item if it exists, otherwise create it in place -+ * and return the created item. -+ */ -+void *sradix_tree_lookup_create(struct sradix_tree_root *root, -+ unsigned long index, void *(*item_alloc)(void)) -+{ -+ unsigned int height, offset; -+ struct sradix_tree_node *node, *tmp; -+ void *item; -+ int shift, error; -+ -+ if (root->rnode == NULL || (index >> (root->shift * root->height))) { -+ if (item_alloc) { -+ error = sradix_tree_extend(root, index); -+ if (error) -+ return NULL; -+ } else { -+ return NULL; -+ } -+ } -+ -+ node = root->rnode; -+ height = root->height; -+ shift = (height - 1) * root->shift; -+ -+ do { -+ offset = (index >> shift) & root->mask; -+ if (!node->stores[offset]) { -+ if (!(tmp = root->alloc())) -+ return NULL; -+ -+ tmp->height = shift / root->shift; -+ node->stores[offset] = tmp; -+ tmp->parent = node; -+ node->count++; -+ node = tmp; -+ } else { -+ node = node->stores[offset]; -+ } -+ -+ shift -= root->shift; -+ } while (shift > 0); -+ -+ BUG_ON(node->height != 1); -+ offset = index & root->mask; -+ if (node->stores[offset]) { -+ return node->stores[offset]; -+ } else if (item_alloc) { -+ if (!(item = item_alloc())) -+ return NULL; -+ -+ node->stores[offset] = item; -+ -+ /* -+ * NOTE: we do NOT call root->assign here, since this item is -+ * newly created by us having no meaning. Caller can call this -+ * if it's necessary to do so. -+ */ -+ -+ node->count++; -+ root->num++; -+ -+ while (sradix_node_full(root, node)) { -+ node = node->parent; -+ if (!node) -+ break; -+ -+ node->fulls++; -+ } -+ -+ if (unlikely(!node)) { -+ /* All nodes are full */ -+ root->min = 1 << (root->height * root->shift); -+ } else { -+ if (root->min == index) { -+ root->min |= (1UL << (node->height - 1)) - 1; -+ root->min++; -+ root->enter_node = node; -+ } -+ } -+ -+ return item; -+ } else { -+ return NULL; -+ } -+ -+} -+ -+int sradix_tree_delete(struct sradix_tree_root *root, unsigned long index) -+{ -+ unsigned int height, offset; -+ struct sradix_tree_node *node; -+ int shift; -+ -+ node = root->rnode; -+ if (node == NULL || (index >> (root->shift * root->height))) -+ return -ENOENT; -+ -+ height = root->height; -+ shift = (height - 1) * root->shift; -+ -+ do { -+ offset = (index >> shift) & root->mask; -+ node = node->stores[offset]; -+ if (!node) -+ return -ENOENT; -+ -+ shift -= root->shift; -+ } while (shift > 0); -+ -+ offset = index & root->mask; -+ if (!node->stores[offset]) -+ return -ENOENT; -+ -+ sradix_tree_delete_from_leaf(root, node, index); -+ -+ return 0; -+} -diff --git a/mm/Kconfig b/mm/Kconfig -index e742d06..93c2533 100644 ---- a/mm/Kconfig -+++ b/mm/Kconfig -@@ -315,6 +315,32 @@ config KSM - See Documentation/vm/ksm.txt for more information: KSM is inactive - until a program has madvised that an area is MADV_MERGEABLE, and - root has set /sys/kernel/mm/ksm/run to 1 (if CONFIG_SYSFS is set). -+choice -+ prompt "Choose UKSM/KSM strategy" -+ default UKSM -+ depends on KSM -+ help -+ This option allows to select a UKSM/KSM stragety. -+ -+config UKSM -+ bool "Ultra-KSM for page merging" -+ depends on KSM -+ help -+ UKSM is inspired by the Linux kernel project \u2014 KSM(Kernel Same -+ page Merging), but with a fundamentally rewritten core algorithm. With -+ an advanced algorithm, UKSM now can transparently scans all anonymously -+ mapped user space applications with an significantly improved scan speed -+ and CPU efficiency. Since KVM is friendly to KSM, KVM can also benefit from -+ UKSM. Now UKSM has its first stable release and first real world enterprise user. -+ For more information, please goto its project page. -+ (www.kerneldedup.org) -+ -+config KSM_LEGACY -+ bool "Legacy KSM implementation" -+ depends on KSM -+ help -+ The legacy KSM implementation from Redhat. -+endchoice - - config DEFAULT_MMAP_MIN_ADDR - int "Low address space to protect from user allocation" -diff --git a/mm/Makefile b/mm/Makefile -index 72c5acb..77882b7 100644 ---- a/mm/Makefile -+++ b/mm/Makefile -@@ -39,7 +39,8 @@ obj-$(CONFIG_SPARSEMEM) += sparse.o - obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o - obj-$(CONFIG_SLOB) += slob.o - obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o --obj-$(CONFIG_KSM) += ksm.o -+obj-$(CONFIG_KSM_LEGACY) += ksm.o -+obj-$(CONFIG_UKSM) += uksm.o - obj-$(CONFIG_PAGE_POISONING) += debug-pagealloc.o - obj-$(CONFIG_SLAB) += slab.o - obj-$(CONFIG_SLUB) += slub.o -diff --git a/mm/memory.c b/mm/memory.c -index 61a262b..a506b9d 100644 ---- a/mm/memory.c -+++ b/mm/memory.c -@@ -118,6 +118,27 @@ __setup("norandmaps", disable_randmaps); - unsigned long zero_pfn __read_mostly; - unsigned long highest_memmap_pfn __read_mostly; - -+#ifdef CONFIG_UKSM -+unsigned long uksm_zero_pfn __read_mostly; -+struct page *empty_uksm_zero_page; -+ -+static int __init setup_uksm_zero_page(void) -+{ -+ unsigned long addr; -+ addr = __get_free_pages(GFP_KERNEL | __GFP_ZERO, 0); -+ if (!addr) -+ panic("Oh boy, that early out of memory?"); -+ -+ empty_uksm_zero_page = virt_to_page((void *) addr); -+ SetPageReserved(empty_uksm_zero_page); -+ -+ uksm_zero_pfn = page_to_pfn(empty_uksm_zero_page); -+ -+ return 0; -+} -+core_initcall(setup_uksm_zero_page); -+#endif -+ - /* - * CONFIG_MMU architectures set up ZERO_PAGE in their paging_init() - */ -@@ -129,6 +150,7 @@ static int __init init_zero_pfn(void) - core_initcall(init_zero_pfn); - - -+ - #if defined(SPLIT_RSS_COUNTING) - - void sync_mm_rss(struct mm_struct *mm) -@@ -896,6 +918,11 @@ copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, - rss[MM_ANONPAGES]++; - else - rss[MM_FILEPAGES]++; -+ -+ /* Should return NULL in vm_normal_page() */ -+ uksm_bugon_zeropage(pte); -+ } else { -+ uksm_map_zero_page(pte); - } - - out_set_pte: -@@ -1138,8 +1165,10 @@ again: - ptent = ptep_get_and_clear_full(mm, addr, pte, - tlb->fullmm); - tlb_remove_tlb_entry(tlb, pte, addr); -- if (unlikely(!page)) -+ if (unlikely(!page)) { -+ uksm_unmap_zero_page(ptent); - continue; -+ } - if (unlikely(details) && details->nonlinear_vma - && linear_page_index(details->nonlinear_vma, - addr) != page->index) -@@ -1704,7 +1733,7 @@ long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, - - VM_BUG_ON(!!pages != !!(gup_flags & FOLL_GET)); - -- /* -+ /* - * Require read or write permissions. - * If FOLL_FORCE is set, we only require the "MAY" flags. - */ -@@ -1764,7 +1793,7 @@ long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, - page = vm_normal_page(vma, start, *pte); - if (!page) { - if (!(gup_flags & FOLL_DUMP) && -- is_zero_pfn(pte_pfn(*pte))) -+ (is_zero_pfn(pte_pfn(*pte)))) - page = pte_page(*pte); - else { - pte_unmap(pte); -@@ -2579,8 +2608,10 @@ static inline void cow_user_page(struct page *dst, struct page *src, unsigned lo - clear_page(kaddr); - kunmap_atomic(kaddr); - flush_dcache_page(dst); -- } else -+ } else { - copy_user_highpage(dst, src, va, vma); -+ uksm_cow_page(vma, src); -+ } - } - - /* -@@ -2779,6 +2810,7 @@ gotten: - new_page = alloc_zeroed_user_highpage_movable(vma, address); - if (!new_page) - goto oom; -+ uksm_cow_pte(vma, orig_pte); - } else { - new_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address); - if (!new_page) -@@ -2804,8 +2836,11 @@ gotten: - dec_mm_counter_fast(mm, MM_FILEPAGES); - inc_mm_counter_fast(mm, MM_ANONPAGES); - } -- } else -+ uksm_bugon_zeropage(orig_pte); -+ } else { -+ uksm_unmap_zero_page(orig_pte); - inc_mm_counter_fast(mm, MM_ANONPAGES); -+ } - flush_cache_page(vma, address, pte_pfn(orig_pte)); - entry = mk_pte(new_page, vma->vm_page_prot); - entry = maybe_mkwrite(pte_mkdirty(entry), vma); -diff --git a/mm/mmap.c b/mm/mmap.c -index f681e18..31ef952 100644 ---- a/mm/mmap.c -+++ b/mm/mmap.c -@@ -36,6 +36,7 @@ - #include - #include - #include -+#include - - #include - #include -@@ -65,7 +66,7 @@ static void unmap_region(struct mm_struct *mm, - * MAP_SHARED r: (no) no r: (yes) yes r: (no) yes r: (no) yes - * w: (no) no w: (no) no w: (yes) yes w: (no) no - * x: (no) no x: (no) yes x: (no) yes x: (yes) yes -- * -+ * - * MAP_PRIVATE r: (no) no r: (yes) yes r: (no) yes r: (no) yes - * w: (no) no w: (no) no w: (copy) copy w: (no) no - * x: (no) no x: (no) yes x: (no) yes x: (yes) yes -@@ -252,6 +253,7 @@ static struct vm_area_struct *remove_vma(struct vm_area_struct *vma) - if (vma->vm_file) - fput(vma->vm_file); - mpol_put(vma_policy(vma)); -+ uksm_remove_vma(vma); - kmem_cache_free(vm_area_cachep, vma); - return next; - } -@@ -707,9 +709,16 @@ int vma_adjust(struct vm_area_struct *vma, unsigned long start, - long adjust_next = 0; - int remove_next = 0; - -+/* -+ * to avoid deadlock, ksm_remove_vma must be done before any spin_lock is -+ * acquired -+ */ -+ uksm_remove_vma(vma); -+ - if (next && !insert) { - struct vm_area_struct *exporter = NULL; - -+ uksm_remove_vma(next); - if (end >= next->vm_end) { - /* - * vma expands, overlapping all the next, and -@@ -803,6 +812,7 @@ again: remove_next = 1 + (end > next->vm_end); - end_changed = true; - } - vma->vm_pgoff = pgoff; -+ - if (adjust_next) { - next->vm_start += adjust_next << PAGE_SHIFT; - next->vm_pgoff += adjust_next; -@@ -873,16 +883,22 @@ again: remove_next = 1 + (end > next->vm_end); - * up the code too much to do both in one go. - */ - next = vma->vm_next; -- if (remove_next == 2) -+ if (remove_next == 2) { -+ uksm_remove_vma(next); - goto again; -- else if (next) -+ } else if (next) { - vma_gap_update(next); -- else -+ } else { - mm->highest_vm_end = end; -+ } -+ } else { -+ if (next && !insert) -+ uksm_vma_add_new(next); - } - if (insert && file) - uprobe_mmap(insert); - -+ uksm_vma_add_new(vma); - validate_mm(mm); - - return 0; -@@ -1250,6 +1266,9 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, - vm_flags = calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags) | - mm->def_flags | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC; - -+ /* If uksm is enabled, we add VM_MERGABLE to new VMAs. */ -+ uksm_vm_flags_mod(&vm_flags); -+ - if (flags & MAP_LOCKED) - if (!can_do_mlock()) - return -EPERM; -@@ -1595,6 +1614,7 @@ munmap_back: - - vma_link(mm, vma, prev, rb_link, rb_parent); - file = vma->vm_file; -+ uksm_vma_add_new(vma); - - /* Once vma denies write, undo our temporary denial count */ - if (correct_wcount) -@@ -1626,6 +1646,7 @@ unmap_and_free_vma: - unmap_region(mm, vma, prev, vma->vm_start, vma->vm_end); - charged = 0; - free_vma: -+ uksm_remove_vma(vma); - kmem_cache_free(vm_area_cachep, vma); - unacct_error: - if (charged) -@@ -1874,7 +1895,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, - info.align_mask = 0; - return vm_unmapped_area(&info); - } --#endif -+#endif - - void arch_unmap_area(struct mm_struct *mm, unsigned long addr) - { -@@ -2452,6 +2473,8 @@ static int __split_vma(struct mm_struct * mm, struct vm_area_struct * vma, - else - err = vma_adjust(vma, vma->vm_start, addr, vma->vm_pgoff, new); - -+ uksm_vma_add_new(new); -+ - /* Success. */ - if (!err) - return 0; -@@ -2617,6 +2640,7 @@ static unsigned long do_brk(unsigned long addr, unsigned long len) - return addr; - - flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags; -+ uksm_vm_flags_mod(&flags); - - error = get_unmapped_area(NULL, addr, len, 0, MAP_FIXED); - if (error & ~PAGE_MASK) -@@ -2684,6 +2708,7 @@ static unsigned long do_brk(unsigned long addr, unsigned long len) - vma->vm_flags = flags; - vma->vm_page_prot = vm_get_page_prot(flags); - vma_link(mm, vma, prev, rb_link, rb_parent); -+ uksm_vma_add_new(vma); - out: - perf_event_mmap(vma); - mm->total_vm += len >> PAGE_SHIFT; -@@ -2718,6 +2743,12 @@ void exit_mmap(struct mm_struct *mm) - /* mm's last user has gone, and its about to be pulled down */ - mmu_notifier_release(mm); - -+ /* -+ * Taking write lock on mmap_sem does not harm others, -+ * but it's crucial for uksm to avoid races. -+ */ -+ down_write(&mm->mmap_sem); -+ - if (mm->locked_vm) { - vma = mm->mmap; - while (vma) { -@@ -2754,6 +2785,11 @@ void exit_mmap(struct mm_struct *mm) - } - vm_unacct_memory(nr_accounted); - -+ mm->mmap = NULL; -+ mm->mm_rb = RB_ROOT; -+ mm->mmap_cache = NULL; -+ up_write(&mm->mmap_sem); -+ - WARN_ON(mm->nr_ptes > (FIRST_USER_ADDRESS+PMD_SIZE-1)>>PMD_SHIFT); - } - -@@ -2864,6 +2900,7 @@ struct vm_area_struct *copy_vma(struct vm_area_struct **vmap, - new_vma->vm_ops->open(new_vma); - vma_link(mm, new_vma, prev, rb_link, rb_parent); - *need_rmap_locks = false; -+ uksm_vma_add_new(new_vma); - } - } - return new_vma; -@@ -2965,10 +3002,10 @@ int install_special_mapping(struct mm_struct *mm, - ret = insert_vm_struct(mm, vma); - if (ret) - goto out; -- - mm->total_vm += len >> PAGE_SHIFT; - - perf_event_mmap(vma); -+ uksm_vma_add_new(vma); - - return 0; - -diff --git a/mm/rmap.c b/mm/rmap.c -index 6280da8..645cf22 100644 ---- a/mm/rmap.c -+++ b/mm/rmap.c -@@ -973,9 +973,9 @@ void page_move_anon_rmap(struct page *page, - - /** - * __page_set_anon_rmap - set up new anonymous rmap -- * @page: Page to add to rmap -+ * @page: Page to add to rmap - * @vma: VM area to add page to. -- * @address: User virtual address of the mapping -+ * @address: User virtual address of the mapping - * @exclusive: the page is exclusively owned by the current process - */ - static void __page_set_anon_rmap(struct page *page, -diff --git a/mm/uksm.c b/mm/uksm.c -new file mode 100644 -index 0000000..794867a ---- /dev/null -+++ b/mm/uksm.c -@@ -0,0 +1,5640 @@ -+/* -+ * Ultra KSM. Copyright (C) 2011-2012 Nai Xia -+ * -+ * This is an improvement upon KSM. Some basic data structures and routines -+ * are borrowed from ksm.c . -+ * -+ * Its new features: -+ * 1. Full system scan: -+ * It automatically scans all user processes' anonymous VMAs. Kernel-user -+ * interaction to submit a memory area to KSM is no longer needed. -+ * -+ * 2. Rich area detection: -+ * It automatically detects rich areas containing abundant duplicated -+ * pages based. Rich areas are given a full scan speed. Poor areas are -+ * sampled at a reasonable speed with very low CPU consumption. -+ * -+ * 3. Ultra Per-page scan speed improvement: -+ * A new hash algorithm is proposed. As a result, on a machine with -+ * Core(TM)2 Quad Q9300 CPU in 32-bit mode and 800MHZ DDR2 main memory, it -+ * can scan memory areas that does not contain duplicated pages at speed of -+ * 627MB/sec ~ 2445MB/sec and can merge duplicated areas at speed of -+ * 477MB/sec ~ 923MB/sec. -+ * -+ * 4. Thrashing area avoidance: -+ * Thrashing area(an VMA that has frequent Ksm page break-out) can be -+ * filtered out. My benchmark shows it's more efficient than KSM's per-page -+ * hash value based volatile page detection. -+ * -+ * -+ * 5. Misc changes upon KSM: -+ * * It has a fully x86-opitmized memcmp dedicated for 4-byte-aligned page -+ * comparison. It's much faster than default C version on x86. -+ * * rmap_item now has an struct *page member to loosely cache a -+ * address-->page mapping, which reduces too much time-costly -+ * follow_page(). -+ * * The VMA creation/exit procedures are hooked to let the Ultra KSM know. -+ * * try_to_merge_two_pages() now can revert a pte if it fails. No break_ -+ * ksm is needed for this case. -+ * -+ * 6. Full Zero Page consideration(contributed by Figo Zhang) -+ * Now uksmd consider full zero pages as special pages and merge them to an -+ * special unswappable uksm zero page. -+ */ -+ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+#include -+#include "internal.h" -+ -+#ifdef CONFIG_X86 -+#undef memcmp -+ -+#ifdef CONFIG_X86_32 -+#define memcmp memcmpx86_32 -+/* -+ * Compare 4-byte-aligned address s1 and s2, with length n -+ */ -+int memcmpx86_32(void *s1, void *s2, size_t n) -+{ -+ size_t num = n / 4; -+ register int res; -+ -+ __asm__ __volatile__ -+ ( -+ "testl %3,%3\n\t" -+ "repe; cmpsd\n\t" -+ "je 1f\n\t" -+ "sbbl %0,%0\n\t" -+ "orl $1,%0\n" -+ "1:" -+ : "=&a" (res), "+&S" (s1), "+&D" (s2), "+&c" (num) -+ : "0" (0) -+ : "cc"); -+ -+ return res; -+} -+ -+/* -+ * Check the page is all zero ? -+ */ -+static int is_full_zero(const void *s1, size_t len) -+{ -+ unsigned char same; -+ -+ len /= 4; -+ -+ __asm__ __volatile__ -+ ("repe; scasl;" -+ "sete %0" -+ : "=qm" (same), "+D" (s1), "+c" (len) -+ : "a" (0) -+ : "cc"); -+ -+ return same; -+} -+ -+ -+#elif defined(CONFIG_X86_64) -+#define memcmp memcmpx86_64 -+/* -+ * Compare 8-byte-aligned address s1 and s2, with length n -+ */ -+int memcmpx86_64(void *s1, void *s2, size_t n) -+{ -+ size_t num = n / 8; -+ register int res; -+ -+ __asm__ __volatile__ -+ ( -+ "testq %q3,%q3\n\t" -+ "repe; cmpsq\n\t" -+ "je 1f\n\t" -+ "sbbq %q0,%q0\n\t" -+ "orq $1,%q0\n" -+ "1:" -+ : "=&a" (res), "+&S" (s1), "+&D" (s2), "+&c" (num) -+ : "0" (0) -+ : "cc"); -+ -+ return res; -+} -+ -+static int is_full_zero(const void *s1, size_t len) -+{ -+ unsigned char same; -+ -+ len /= 8; -+ -+ __asm__ __volatile__ -+ ("repe; scasq;" -+ "sete %0" -+ : "=qm" (same), "+D" (s1), "+c" (len) -+ : "a" (0) -+ : "cc"); -+ -+ return same; -+} -+ -+#endif -+#else -+static int is_full_zero(const void *s1, size_t len) -+{ -+ unsigned long *src = s1; -+ int i; -+ -+ len /= sizeof(*src); -+ -+ for (i = 0; i < len; i++) { -+ if (src[i]) -+ return 0; -+ } -+ -+ return 1; -+} -+#endif -+ -+#define U64_MAX (~((u64)0)) -+#define UKSM_RUNG_ROUND_FINISHED (1 << 0) -+#define TIME_RATIO_SCALE 10000 -+ -+#define SLOT_TREE_NODE_SHIFT 8 -+#define SLOT_TREE_NODE_STORE_SIZE (1UL << SLOT_TREE_NODE_SHIFT) -+struct slot_tree_node { -+ unsigned long size; -+ struct sradix_tree_node snode; -+ void *stores[SLOT_TREE_NODE_STORE_SIZE]; -+}; -+ -+static struct kmem_cache *slot_tree_node_cachep; -+ -+static struct sradix_tree_node *slot_tree_node_alloc(void) -+{ -+ struct slot_tree_node *p; -+ p = kmem_cache_zalloc(slot_tree_node_cachep, GFP_KERNEL); -+ if (!p) -+ return NULL; -+ -+ return &p->snode; -+} -+ -+static void slot_tree_node_free(struct sradix_tree_node *node) -+{ -+ struct slot_tree_node *p; -+ -+ p = container_of(node, struct slot_tree_node, snode); -+ kmem_cache_free(slot_tree_node_cachep, p); -+} -+ -+static void slot_tree_node_extend(struct sradix_tree_node *parent, -+ struct sradix_tree_node *child) -+{ -+ struct slot_tree_node *p, *c; -+ -+ p = container_of(parent, struct slot_tree_node, snode); -+ c = container_of(child, struct slot_tree_node, snode); -+ -+ p->size += c->size; -+} -+ -+void slot_tree_node_assign(struct sradix_tree_node *node, -+ unsigned index, void *item) -+{ -+ struct vma_slot *slot = item; -+ struct slot_tree_node *cur; -+ -+ slot->snode = node; -+ slot->sindex = index; -+ -+ while (node) { -+ cur = container_of(node, struct slot_tree_node, snode); -+ cur->size += slot->pages; -+ node = node->parent; -+ } -+} -+ -+void slot_tree_node_rm(struct sradix_tree_node *node, unsigned offset) -+{ -+ struct vma_slot *slot; -+ struct slot_tree_node *cur; -+ unsigned long pages; -+ -+ if (node->height == 1) { -+ slot = node->stores[offset]; -+ pages = slot->pages; -+ } else { -+ cur = container_of(node->stores[offset], -+ struct slot_tree_node, snode); -+ pages = cur->size; -+ } -+ -+ while (node) { -+ cur = container_of(node, struct slot_tree_node, snode); -+ cur->size -= pages; -+ node = node->parent; -+ } -+} -+ -+unsigned long slot_iter_index; -+int slot_iter(void *item, unsigned long height) -+{ -+ struct slot_tree_node *node; -+ struct vma_slot *slot; -+ -+ if (height == 1) { -+ slot = item; -+ if (slot_iter_index < slot->pages) { -+ /*in this one*/ -+ return 1; -+ } else { -+ slot_iter_index -= slot->pages; -+ return 0; -+ } -+ -+ } else { -+ node = container_of(item, struct slot_tree_node, snode); -+ if (slot_iter_index < node->size) { -+ /*in this one*/ -+ return 1; -+ } else { -+ slot_iter_index -= node->size; -+ return 0; -+ } -+ } -+} -+ -+ -+static inline void slot_tree_init_root(struct sradix_tree_root *root) -+{ -+ init_sradix_tree_root(root, SLOT_TREE_NODE_SHIFT); -+ root->alloc = slot_tree_node_alloc; -+ root->free = slot_tree_node_free; -+ root->extend = slot_tree_node_extend; -+ root->assign = slot_tree_node_assign; -+ root->rm = slot_tree_node_rm; -+} -+ -+void slot_tree_init(void) -+{ -+ slot_tree_node_cachep = kmem_cache_create("slot_tree_node", -+ sizeof(struct slot_tree_node), 0, -+ SLAB_PANIC | SLAB_RECLAIM_ACCOUNT, -+ NULL); -+} -+ -+ -+/* Each rung of this ladder is a list of VMAs having a same scan ratio */ -+struct scan_rung { -+ //struct list_head scanned_list; -+ struct sradix_tree_root vma_root; -+ struct sradix_tree_root vma_root2; -+ -+ struct vma_slot *current_scan; -+ unsigned long current_offset; -+ -+ /* -+ * The initial value for current_offset, it should loop over -+ * [0~ step - 1] to let all slot have its chance to be scanned. -+ */ -+ unsigned long offset_init; -+ unsigned long step; /* dynamic step for current_offset */ -+ unsigned int flags; -+ unsigned long pages_to_scan; -+ //unsigned long fully_scanned_slots; -+ /* -+ * a little bit tricky - if cpu_time_ratio > 0, then the value is the -+ * the cpu time ratio it can spend in rung_i for every scan -+ * period. if < 0, then it is the cpu time ratio relative to the -+ * max cpu percentage user specified. Both in unit of -+ * 1/TIME_RATIO_SCALE -+ */ -+ int cpu_ratio; -+ -+ /* -+ * How long it will take for all slots in this rung to be fully -+ * scanned? If it's zero, we don't care about the cover time: -+ * it's fully scanned. -+ */ -+ unsigned int cover_msecs; -+ //unsigned long vma_num; -+ //unsigned long pages; /* Sum of all slot's pages in rung */ -+}; -+ -+/** -+ * node of either the stable or unstale rbtree -+ * -+ */ -+struct tree_node { -+ struct rb_node node; /* link in the main (un)stable rbtree */ -+ struct rb_root sub_root; /* rb_root for sublevel collision rbtree */ -+ u32 hash; -+ unsigned long count; /* TODO: merged with sub_root */ -+ struct list_head all_list; /* all tree nodes in stable/unstable tree */ -+}; -+ -+/** -+ * struct stable_node - node of the stable rbtree -+ * @node: rb node of this ksm page in the stable tree -+ * @hlist: hlist head of rmap_items using this ksm page -+ * @kpfn: page frame number of this ksm page -+ */ -+struct stable_node { -+ struct rb_node node; /* link in sub-rbtree */ -+ struct tree_node *tree_node; /* it's tree node root in stable tree, NULL if it's in hell list */ -+ struct hlist_head hlist; -+ unsigned long kpfn; -+ u32 hash_max; /* if ==0 then it's not been calculated yet */ -+ struct list_head all_list; /* in a list for all stable nodes */ -+}; -+ -+/** -+ * struct node_vma - group rmap_items linked in a same stable -+ * node together. -+ */ -+struct node_vma { -+ union { -+ struct vma_slot *slot; -+ unsigned long key; /* slot is used as key sorted on hlist */ -+ }; -+ struct hlist_node hlist; -+ struct hlist_head rmap_hlist; -+ struct stable_node *head; -+}; -+ -+/** -+ * struct rmap_item - reverse mapping item for virtual addresses -+ * @rmap_list: next rmap_item in mm_slot's singly-linked rmap_list -+ * @anon_vma: pointer to anon_vma for this mm,address, when in stable tree -+ * @mm: the memory structure this rmap_item is pointing into -+ * @address: the virtual address this rmap_item tracks (+ flags in low bits) -+ * @node: rb node of this rmap_item in the unstable tree -+ * @head: pointer to stable_node heading this list in the stable tree -+ * @hlist: link into hlist of rmap_items hanging off that stable_node -+ */ -+struct rmap_item { -+ struct vma_slot *slot; -+ struct page *page; -+ unsigned long address; /* + low bits used for flags below */ -+ unsigned long hash_round; -+ unsigned long entry_index; -+ union { -+ struct {/* when in unstable tree */ -+ struct rb_node node; -+ struct tree_node *tree_node; -+ u32 hash_max; -+ }; -+ struct { /* when in stable tree */ -+ struct node_vma *head; -+ struct hlist_node hlist; -+ struct anon_vma *anon_vma; -+ }; -+ }; -+} __attribute__((aligned(4))); -+ -+struct rmap_list_entry { -+ union { -+ struct rmap_item *item; -+ unsigned long addr; -+ }; -+ /* lowest bit is used for is_addr tag */ -+} __attribute__((aligned(4))); /* 4 aligned to fit in to pages*/ -+ -+ -+/* Basic data structure definition ends */ -+ -+ -+/* -+ * Flags for rmap_item to judge if it's listed in the stable/unstable tree. -+ * The flags use the low bits of rmap_item.address -+ */ -+#define UNSTABLE_FLAG 0x1 -+#define STABLE_FLAG 0x2 -+#define get_rmap_addr(x) ((x)->address & PAGE_MASK) -+ -+/* -+ * rmap_list_entry helpers -+ */ -+#define IS_ADDR_FLAG 1 -+#define is_addr(ptr) ((unsigned long)(ptr) & IS_ADDR_FLAG) -+#define set_is_addr(ptr) ((ptr) |= IS_ADDR_FLAG) -+#define get_clean_addr(ptr) (((ptr) & ~(__typeof__(ptr))IS_ADDR_FLAG)) -+ -+ -+/* -+ * High speed caches for frequently allocated and freed structs -+ */ -+static struct kmem_cache *rmap_item_cache; -+static struct kmem_cache *stable_node_cache; -+static struct kmem_cache *node_vma_cache; -+static struct kmem_cache *vma_slot_cache; -+static struct kmem_cache *tree_node_cache; -+#define UKSM_KMEM_CACHE(__struct, __flags) kmem_cache_create("uksm_"#__struct,\ -+ sizeof(struct __struct), __alignof__(struct __struct),\ -+ (__flags), NULL) -+ -+/* Array of all scan_rung, uksm_scan_ladder[0] having the minimum scan ratio */ -+#define SCAN_LADDER_SIZE 4 -+static struct scan_rung uksm_scan_ladder[SCAN_LADDER_SIZE]; -+ -+/* The evaluation rounds uksmd has finished */ -+static unsigned long long uksm_eval_round = 1; -+ -+/* -+ * we add 1 to this var when we consider we should rebuild the whole -+ * unstable tree. -+ */ -+static unsigned long uksm_hash_round = 1; -+ -+/* -+ * How many times the whole memory is scanned. -+ */ -+static unsigned long long fully_scanned_round = 1; -+ -+/* The total number of virtual pages of all vma slots */ -+static u64 uksm_pages_total; -+ -+/* The number of pages has been scanned since the start up */ -+static u64 uksm_pages_scanned; -+ -+static u64 scanned_virtual_pages; -+ -+/* The number of pages has been scanned since last encode_benefit call */ -+static u64 uksm_pages_scanned_last; -+ -+/* If the scanned number is tooo large, we encode it here */ -+static u64 pages_scanned_stored; -+ -+static unsigned long pages_scanned_base; -+ -+/* The number of nodes in the stable tree */ -+static unsigned long uksm_pages_shared; -+ -+/* The number of page slots additionally sharing those nodes */ -+static unsigned long uksm_pages_sharing; -+ -+/* The number of nodes in the unstable tree */ -+static unsigned long uksm_pages_unshared; -+ -+/* -+ * Milliseconds ksmd should sleep between scans, -+ * >= 100ms to be consistent with -+ * scan_time_to_sleep_msec() -+ */ -+static unsigned int uksm_sleep_jiffies; -+ -+/* The real value for the uksmd next sleep */ -+static unsigned int uksm_sleep_real; -+ -+/* Saved value for user input uksm_sleep_jiffies when it's enlarged */ -+static unsigned int uksm_sleep_saved; -+ -+/* Max percentage of cpu utilization ksmd can take to scan in one batch */ -+static unsigned int uksm_max_cpu_percentage; -+ -+static int uksm_cpu_governor; -+ -+static char *uksm_cpu_governor_str[4] = { "full", "medium", "low", "quiet" }; -+ -+struct uksm_cpu_preset_s { -+ int cpu_ratio[SCAN_LADDER_SIZE]; -+ unsigned int cover_msecs[SCAN_LADDER_SIZE]; -+ unsigned int max_cpu; /* percentage */ -+}; -+ -+struct uksm_cpu_preset_s uksm_cpu_preset[4] = { -+ { {20, 40, -2500, -10000}, {1000, 500, 200, 50}, 95}, -+ { {20, 30, -2500, -10000}, {1000, 500, 400, 100}, 50}, -+ { {10, 20, -5000, -10000}, {1500, 1000, 1000, 250}, 20}, -+ { {10, 20, 40, 75}, {2000, 1000, 1000, 1000}, 1}, -+}; -+ -+/* The default value for uksm_ema_page_time if it's not initialized */ -+#define UKSM_PAGE_TIME_DEFAULT 500 -+ -+/*cost to scan one page by expotional moving average in nsecs */ -+static unsigned long uksm_ema_page_time = UKSM_PAGE_TIME_DEFAULT; -+ -+/* The expotional moving average alpha weight, in percentage. */ -+#define EMA_ALPHA 20 -+ -+/* -+ * The threshold used to filter out thrashing areas, -+ * If it == 0, filtering is disabled, otherwise it's the percentage up-bound -+ * of the thrashing ratio of all areas. Any area with a bigger thrashing ratio -+ * will be considered as having a zero duplication ratio. -+ */ -+static unsigned int uksm_thrash_threshold = 50; -+ -+/* How much dedup ratio is considered to be abundant*/ -+static unsigned int uksm_abundant_threshold = 10; -+ -+/* All slots having merged pages in this eval round. */ -+struct list_head vma_slot_dedup = LIST_HEAD_INIT(vma_slot_dedup); -+ -+/* How many times the ksmd has slept since startup */ -+static unsigned long long uksm_sleep_times; -+ -+#define UKSM_RUN_STOP 0 -+#define UKSM_RUN_MERGE 1 -+static unsigned int uksm_run = 1; -+ -+static DECLARE_WAIT_QUEUE_HEAD(uksm_thread_wait); -+static DEFINE_MUTEX(uksm_thread_mutex); -+ -+/* -+ * List vma_slot_new is for newly created vma_slot waiting to be added by -+ * ksmd. If one cannot be added(e.g. due to it's too small), it's moved to -+ * vma_slot_noadd. vma_slot_del is the list for vma_slot whose corresponding -+ * VMA has been removed/freed. -+ */ -+struct list_head vma_slot_new = LIST_HEAD_INIT(vma_slot_new); -+struct list_head vma_slot_noadd = LIST_HEAD_INIT(vma_slot_noadd); -+struct list_head vma_slot_del = LIST_HEAD_INIT(vma_slot_del); -+static DEFINE_SPINLOCK(vma_slot_list_lock); -+ -+/* The unstable tree heads */ -+static struct rb_root root_unstable_tree = RB_ROOT; -+ -+/* -+ * All tree_nodes are in a list to be freed at once when unstable tree is -+ * freed after each scan round. -+ */ -+static struct list_head unstable_tree_node_list = -+ LIST_HEAD_INIT(unstable_tree_node_list); -+ -+/* List contains all stable nodes */ -+static struct list_head stable_node_list = LIST_HEAD_INIT(stable_node_list); -+ -+/* -+ * When the hash strength is changed, the stable tree must be delta_hashed and -+ * re-structured. We use two set of below structs to speed up the -+ * re-structuring of stable tree. -+ */ -+static struct list_head -+stable_tree_node_list[2] = {LIST_HEAD_INIT(stable_tree_node_list[0]), -+ LIST_HEAD_INIT(stable_tree_node_list[1])}; -+ -+static struct list_head *stable_tree_node_listp = &stable_tree_node_list[0]; -+static struct rb_root root_stable_tree[2] = {RB_ROOT, RB_ROOT}; -+static struct rb_root *root_stable_treep = &root_stable_tree[0]; -+static unsigned long stable_tree_index; -+ -+/* The hash strength needed to hash a full page */ -+#define HASH_STRENGTH_FULL (PAGE_SIZE / sizeof(u32)) -+ -+/* The hash strength needed for loop-back hashing */ -+#define HASH_STRENGTH_MAX (HASH_STRENGTH_FULL + 10) -+ -+/* The random offsets in a page */ -+static u32 *random_nums; -+ -+/* The hash strength */ -+static unsigned long hash_strength = HASH_STRENGTH_FULL >> 4; -+ -+/* The delta value each time the hash strength increases or decreases */ -+static unsigned long hash_strength_delta; -+#define HASH_STRENGTH_DELTA_MAX 5 -+ -+/* The time we have saved due to random_sample_hash */ -+static u64 rshash_pos; -+ -+/* The time we have wasted due to hash collision */ -+static u64 rshash_neg; -+ -+struct uksm_benefit { -+ u64 pos; -+ u64 neg; -+ u64 scanned; -+ unsigned long base; -+} benefit; -+ -+/* -+ * The relative cost of memcmp, compared to 1 time unit of random sample -+ * hash, this value is tested when ksm module is initialized -+ */ -+static unsigned long memcmp_cost; -+ -+static unsigned long rshash_neg_cont_zero; -+static unsigned long rshash_cont_obscure; -+ -+/* The possible states of hash strength adjustment heuristic */ -+enum rshash_states { -+ RSHASH_STILL, -+ RSHASH_TRYUP, -+ RSHASH_TRYDOWN, -+ RSHASH_NEW, -+ RSHASH_PRE_STILL, -+}; -+ -+/* The possible direction we are about to adjust hash strength */ -+enum rshash_direct { -+ GO_UP, -+ GO_DOWN, -+ OBSCURE, -+ STILL, -+}; -+ -+/* random sampling hash state machine */ -+static struct { -+ enum rshash_states state; -+ enum rshash_direct pre_direct; -+ u8 below_count; -+ /* Keep a lookup window of size 5, iff above_count/below_count > 3 -+ * in this window we stop trying. -+ */ -+ u8 lookup_window_index; -+ u64 stable_benefit; -+ unsigned long turn_point_down; -+ unsigned long turn_benefit_down; -+ unsigned long turn_point_up; -+ unsigned long turn_benefit_up; -+ unsigned long stable_point; -+} rshash_state; -+ -+/*zero page hash table, hash_strength [0 ~ HASH_STRENGTH_MAX]*/ -+static u32 *zero_hash_table; -+ -+static inline struct node_vma *alloc_node_vma(void) -+{ -+ struct node_vma *node_vma; -+ node_vma = kmem_cache_zalloc(node_vma_cache, GFP_KERNEL); -+ if (node_vma) { -+ INIT_HLIST_HEAD(&node_vma->rmap_hlist); -+ INIT_HLIST_NODE(&node_vma->hlist); -+ } -+ return node_vma; -+} -+ -+static inline void free_node_vma(struct node_vma *node_vma) -+{ -+ kmem_cache_free(node_vma_cache, node_vma); -+} -+ -+ -+static inline struct vma_slot *alloc_vma_slot(void) -+{ -+ struct vma_slot *slot; -+ -+ /* -+ * In case ksm is not initialized by now. -+ * Oops, we need to consider the call site of uksm_init() in the future. -+ */ -+ if (!vma_slot_cache) -+ return NULL; -+ -+ slot = kmem_cache_zalloc(vma_slot_cache, GFP_KERNEL); -+ if (slot) { -+ INIT_LIST_HEAD(&slot->slot_list); -+ INIT_LIST_HEAD(&slot->dedup_list); -+ slot->flags |= UKSM_SLOT_NEED_RERAND; -+ } -+ return slot; -+} -+ -+static inline void free_vma_slot(struct vma_slot *vma_slot) -+{ -+ kmem_cache_free(vma_slot_cache, vma_slot); -+} -+ -+ -+ -+static inline struct rmap_item *alloc_rmap_item(void) -+{ -+ struct rmap_item *rmap_item; -+ -+ rmap_item = kmem_cache_zalloc(rmap_item_cache, GFP_KERNEL); -+ if (rmap_item) { -+ /* bug on lowest bit is not clear for flag use */ -+ BUG_ON(is_addr(rmap_item)); -+ } -+ return rmap_item; -+} -+ -+static inline void free_rmap_item(struct rmap_item *rmap_item) -+{ -+ rmap_item->slot = NULL; /* debug safety */ -+ kmem_cache_free(rmap_item_cache, rmap_item); -+} -+ -+static inline struct stable_node *alloc_stable_node(void) -+{ -+ struct stable_node *node; -+ node = kmem_cache_alloc(stable_node_cache, GFP_KERNEL | GFP_ATOMIC); -+ if (!node) -+ return NULL; -+ -+ INIT_HLIST_HEAD(&node->hlist); -+ list_add(&node->all_list, &stable_node_list); -+ return node; -+} -+ -+static inline void free_stable_node(struct stable_node *stable_node) -+{ -+ list_del(&stable_node->all_list); -+ kmem_cache_free(stable_node_cache, stable_node); -+} -+ -+static inline struct tree_node *alloc_tree_node(struct list_head *list) -+{ -+ struct tree_node *node; -+ node = kmem_cache_zalloc(tree_node_cache, GFP_KERNEL | GFP_ATOMIC); -+ if (!node) -+ return NULL; -+ -+ list_add(&node->all_list, list); -+ return node; -+} -+ -+static inline void free_tree_node(struct tree_node *node) -+{ -+ list_del(&node->all_list); -+ kmem_cache_free(tree_node_cache, node); -+} -+ -+static void uksm_drop_anon_vma(struct rmap_item *rmap_item) -+{ -+ struct anon_vma *anon_vma = rmap_item->anon_vma; -+ -+ put_anon_vma(anon_vma); -+} -+ -+ -+/** -+ * Remove a stable node from stable_tree, may unlink from its tree_node and -+ * may remove its parent tree_node if no other stable node is pending. -+ * -+ * @stable_node The node need to be removed -+ * @unlink_rb Will this node be unlinked from the rbtree? -+ * @remove_tree_ node Will its tree_node be removed if empty? -+ */ -+static void remove_node_from_stable_tree(struct stable_node *stable_node, -+ int unlink_rb, int remove_tree_node) -+{ -+ struct node_vma *node_vma; -+ struct rmap_item *rmap_item; -+ struct hlist_node *n; -+ -+ if (!hlist_empty(&stable_node->hlist)) { -+ hlist_for_each_entry_safe(node_vma, n, -+ &stable_node->hlist, hlist) { -+ hlist_for_each_entry(rmap_item, &node_vma->rmap_hlist, hlist) { -+ uksm_pages_sharing--; -+ -+ uksm_drop_anon_vma(rmap_item); -+ rmap_item->address &= PAGE_MASK; -+ } -+ free_node_vma(node_vma); -+ cond_resched(); -+ } -+ -+ /* the last one is counted as shared */ -+ uksm_pages_shared--; -+ uksm_pages_sharing++; -+ } -+ -+ if (stable_node->tree_node && unlink_rb) { -+ rb_erase(&stable_node->node, -+ &stable_node->tree_node->sub_root); -+ -+ if (RB_EMPTY_ROOT(&stable_node->tree_node->sub_root) && -+ remove_tree_node) { -+ rb_erase(&stable_node->tree_node->node, -+ root_stable_treep); -+ free_tree_node(stable_node->tree_node); -+ } else { -+ stable_node->tree_node->count--; -+ } -+ } -+ -+ free_stable_node(stable_node); -+} -+ -+ -+/* -+ * get_uksm_page: checks if the page indicated by the stable node -+ * is still its ksm page, despite having held no reference to it. -+ * In which case we can trust the content of the page, and it -+ * returns the gotten page; but if the page has now been zapped, -+ * remove the stale node from the stable tree and return NULL. -+ * -+ * You would expect the stable_node to hold a reference to the ksm page. -+ * But if it increments the page's count, swapping out has to wait for -+ * ksmd to come around again before it can free the page, which may take -+ * seconds or even minutes: much too unresponsive. So instead we use a -+ * "keyhole reference": access to the ksm page from the stable node peeps -+ * out through its keyhole to see if that page still holds the right key, -+ * pointing back to this stable node. This relies on freeing a PageAnon -+ * page to reset its page->mapping to NULL, and relies on no other use of -+ * a page to put something that might look like our key in page->mapping. -+ * -+ * include/linux/pagemap.h page_cache_get_speculative() is a good reference, -+ * but this is different - made simpler by uksm_thread_mutex being held, but -+ * interesting for assuming that no other use of the struct page could ever -+ * put our expected_mapping into page->mapping (or a field of the union which -+ * coincides with page->mapping). The RCU calls are not for KSM at all, but -+ * to keep the page_count protocol described with page_cache_get_speculative. -+ * -+ * Note: it is possible that get_uksm_page() will return NULL one moment, -+ * then page the next, if the page is in between page_freeze_refs() and -+ * page_unfreeze_refs(): this shouldn't be a problem anywhere, the page -+ * is on its way to being freed; but it is an anomaly to bear in mind. -+ * -+ * @unlink_rb: if the removal of this node will firstly unlink from -+ * its rbtree. stable_node_reinsert will prevent this when restructuring the -+ * node from its old tree. -+ * -+ * @remove_tree_node: if this is the last one of its tree_node, will the -+ * tree_node be freed ? If we are inserting stable node, this tree_node may -+ * be reused, so don't free it. -+ */ -+static struct page *get_uksm_page(struct stable_node *stable_node, -+ int unlink_rb, int remove_tree_node) -+{ -+ struct page *page; -+ void *expected_mapping; -+ -+ page = pfn_to_page(stable_node->kpfn); -+ expected_mapping = (void *)stable_node + -+ (PAGE_MAPPING_ANON | PAGE_MAPPING_KSM); -+ rcu_read_lock(); -+ if (page->mapping != expected_mapping) -+ goto stale; -+ if (!get_page_unless_zero(page)) -+ goto stale; -+ if (page->mapping != expected_mapping) { -+ put_page(page); -+ goto stale; -+ } -+ rcu_read_unlock(); -+ return page; -+stale: -+ rcu_read_unlock(); -+ remove_node_from_stable_tree(stable_node, unlink_rb, remove_tree_node); -+ -+ return NULL; -+} -+ -+/* -+ * Removing rmap_item from stable or unstable tree. -+ * This function will clean the information from the stable/unstable tree. -+ */ -+static inline void remove_rmap_item_from_tree(struct rmap_item *rmap_item) -+{ -+ if (rmap_item->address & STABLE_FLAG) { -+ struct stable_node *stable_node; -+ struct node_vma *node_vma; -+ struct page *page; -+ -+ node_vma = rmap_item->head; -+ stable_node = node_vma->head; -+ page = get_uksm_page(stable_node, 1, 1); -+ if (!page) -+ goto out; -+ -+ /* -+ * page lock is needed because it's racing with -+ * try_to_unmap_ksm(), etc. -+ */ -+ lock_page(page); -+ hlist_del(&rmap_item->hlist); -+ -+ if (hlist_empty(&node_vma->rmap_hlist)) { -+ hlist_del(&node_vma->hlist); -+ free_node_vma(node_vma); -+ } -+ unlock_page(page); -+ -+ put_page(page); -+ if (hlist_empty(&stable_node->hlist)) { -+ /* do NOT call remove_node_from_stable_tree() here, -+ * it's possible for a forked rmap_item not in -+ * stable tree while the in-tree rmap_items were -+ * deleted. -+ */ -+ uksm_pages_shared--; -+ } else -+ uksm_pages_sharing--; -+ -+ -+ uksm_drop_anon_vma(rmap_item); -+ } else if (rmap_item->address & UNSTABLE_FLAG) { -+ if (rmap_item->hash_round == uksm_hash_round) { -+ -+ rb_erase(&rmap_item->node, -+ &rmap_item->tree_node->sub_root); -+ if (RB_EMPTY_ROOT(&rmap_item->tree_node->sub_root)) { -+ rb_erase(&rmap_item->tree_node->node, -+ &root_unstable_tree); -+ -+ free_tree_node(rmap_item->tree_node); -+ } else -+ rmap_item->tree_node->count--; -+ } -+ uksm_pages_unshared--; -+ } -+ -+ rmap_item->address &= PAGE_MASK; -+ rmap_item->hash_max = 0; -+ -+out: -+ cond_resched(); /* we're called from many long loops */ -+} -+ -+static inline int slot_in_uksm(struct vma_slot *slot) -+{ -+ return list_empty(&slot->slot_list); -+} -+ -+/* -+ * Test if the mm is exiting -+ */ -+static inline bool uksm_test_exit(struct mm_struct *mm) -+{ -+ return atomic_read(&mm->mm_users) == 0; -+} -+ -+/** -+ * Need to do two things: -+ * 1. check if slot was moved to del list -+ * 2. make sure the mmap_sem is manipulated under valid vma. -+ * -+ * My concern here is that in some cases, this may make -+ * vma_slot_list_lock() waiters to serialized further by some -+ * sem->wait_lock, can this really be expensive? -+ * -+ * -+ * @return -+ * 0: if successfully locked mmap_sem -+ * -ENOENT: this slot was moved to del list -+ * -EBUSY: vma lock failed -+ */ -+static int try_down_read_slot_mmap_sem(struct vma_slot *slot) -+{ -+ struct vm_area_struct *vma; -+ struct mm_struct *mm; -+ struct rw_semaphore *sem; -+ -+ spin_lock(&vma_slot_list_lock); -+ -+ /* the slot_list was removed and inited from new list, when it enters -+ * uksm_list. If now it's not empty, then it must be moved to del list -+ */ -+ if (!slot_in_uksm(slot)) { -+ spin_unlock(&vma_slot_list_lock); -+ return -ENOENT; -+ } -+ -+ BUG_ON(slot->pages != vma_pages(slot->vma)); -+ /* Ok, vma still valid */ -+ vma = slot->vma; -+ mm = vma->vm_mm; -+ sem = &mm->mmap_sem; -+ -+ if (uksm_test_exit(mm)) { -+ spin_unlock(&vma_slot_list_lock); -+ return -ENOENT; -+ } -+ -+ if (down_read_trylock(sem)) { -+ spin_unlock(&vma_slot_list_lock); -+ return 0; -+ } -+ -+ spin_unlock(&vma_slot_list_lock); -+ return -EBUSY; -+} -+ -+static inline unsigned long -+vma_page_address(struct page *page, struct vm_area_struct *vma) -+{ -+ pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT); -+ unsigned long address; -+ -+ address = vma->vm_start + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT); -+ if (unlikely(address < vma->vm_start || address >= vma->vm_end)) { -+ /* page should be within @vma mapping range */ -+ return -EFAULT; -+ } -+ return address; -+} -+ -+ -+/* return 0 on success with the item's mmap_sem locked */ -+static inline int get_mergeable_page_lock_mmap(struct rmap_item *item) -+{ -+ struct mm_struct *mm; -+ struct vma_slot *slot = item->slot; -+ int err = -EINVAL; -+ -+ struct page *page; -+ -+ /* -+ * try_down_read_slot_mmap_sem() returns non-zero if the slot -+ * has been removed by uksm_remove_vma(). -+ */ -+ if (try_down_read_slot_mmap_sem(slot)) -+ return -EBUSY; -+ -+ mm = slot->vma->vm_mm; -+ -+ if (uksm_test_exit(mm)) -+ goto failout_up; -+ -+ page = item->page; -+ rcu_read_lock(); -+ if (!get_page_unless_zero(page)) { -+ rcu_read_unlock(); -+ goto failout_up; -+ } -+ -+ /* No need to consider huge page here. */ -+ if (item->slot->vma->anon_vma != page_anon_vma(page) || -+ vma_page_address(page, item->slot->vma) != get_rmap_addr(item)) { -+ /* -+ * TODO: -+ * should we release this item becase of its stale page -+ * mapping? -+ */ -+ put_page(page); -+ rcu_read_unlock(); -+ goto failout_up; -+ } -+ rcu_read_unlock(); -+ return 0; -+ -+failout_up: -+ up_read(&mm->mmap_sem); -+ return err; -+} -+ -+/* -+ * What kind of VMA is considered ? -+ */ -+static inline int vma_can_enter(struct vm_area_struct *vma) -+{ -+ return uksm_flags_can_scan(vma->vm_flags); -+} -+ -+/* -+ * Called whenever a fresh new vma is created A new vma_slot. -+ * is created and inserted into a global list Must be called. -+ * after vma is inserted to its mm . -+ */ -+void uksm_vma_add_new(struct vm_area_struct *vma) -+{ -+ struct vma_slot *slot; -+ -+ if (!vma_can_enter(vma)) { -+ vma->uksm_vma_slot = NULL; -+ return; -+ } -+ -+ slot = alloc_vma_slot(); -+ if (!slot) { -+ vma->uksm_vma_slot = NULL; -+ return; -+ } -+ -+ vma->uksm_vma_slot = slot; -+ vma->vm_flags |= VM_MERGEABLE; -+ slot->vma = vma; -+ slot->mm = vma->vm_mm; -+ slot->ctime_j = jiffies; -+ slot->pages = vma_pages(vma); -+ spin_lock(&vma_slot_list_lock); -+ list_add_tail(&slot->slot_list, &vma_slot_new); -+ spin_unlock(&vma_slot_list_lock); -+} -+ -+/* -+ * Called after vma is unlinked from its mm -+ */ -+void uksm_remove_vma(struct vm_area_struct *vma) -+{ -+ struct vma_slot *slot; -+ -+ if (!vma->uksm_vma_slot) -+ return; -+ -+ slot = vma->uksm_vma_slot; -+ spin_lock(&vma_slot_list_lock); -+ if (slot_in_uksm(slot)) { -+ /** -+ * This slot has been added by ksmd, so move to the del list -+ * waiting ksmd to free it. -+ */ -+ list_add_tail(&slot->slot_list, &vma_slot_del); -+ } else { -+ /** -+ * It's still on new list. It's ok to free slot directly. -+ */ -+ list_del(&slot->slot_list); -+ free_vma_slot(slot); -+ } -+ spin_unlock(&vma_slot_list_lock); -+ vma->uksm_vma_slot = NULL; -+} -+ -+/* 32/3 < they < 32/2 */ -+#define shiftl 8 -+#define shiftr 12 -+ -+#define HASH_FROM_TO(from, to) \ -+for (index = from; index < to; index++) { \ -+ pos = random_nums[index]; \ -+ hash += key[pos]; \ -+ hash += (hash << shiftl); \ -+ hash ^= (hash >> shiftr); \ -+} -+ -+ -+#define HASH_FROM_DOWN_TO(from, to) \ -+for (index = from - 1; index >= to; index--) { \ -+ hash ^= (hash >> shiftr); \ -+ hash ^= (hash >> (shiftr*2)); \ -+ hash -= (hash << shiftl); \ -+ hash += (hash << (shiftl*2)); \ -+ pos = random_nums[index]; \ -+ hash -= key[pos]; \ -+} -+ -+/* -+ * The main random sample hash function. -+ */ -+static u32 random_sample_hash(void *addr, u32 hash_strength) -+{ -+ u32 hash = 0xdeadbeef; -+ int index, pos, loop = hash_strength; -+ u32 *key = (u32 *)addr; -+ -+ if (loop > HASH_STRENGTH_FULL) -+ loop = HASH_STRENGTH_FULL; -+ -+ HASH_FROM_TO(0, loop); -+ -+ if (hash_strength > HASH_STRENGTH_FULL) { -+ loop = hash_strength - HASH_STRENGTH_FULL; -+ HASH_FROM_TO(0, loop); -+ } -+ -+ return hash; -+} -+ -+ -+/** -+ * It's used when hash strength is adjusted -+ * -+ * @addr The page's virtual address -+ * @from The original hash strength -+ * @to The hash strength changed to -+ * @hash The hash value generated with "from" hash value -+ * -+ * return the hash value -+ */ -+static u32 delta_hash(void *addr, int from, int to, u32 hash) -+{ -+ u32 *key = (u32 *)addr; -+ int index, pos; /* make sure they are int type */ -+ -+ if (to > from) { -+ if (from >= HASH_STRENGTH_FULL) { -+ from -= HASH_STRENGTH_FULL; -+ to -= HASH_STRENGTH_FULL; -+ HASH_FROM_TO(from, to); -+ } else if (to <= HASH_STRENGTH_FULL) { -+ HASH_FROM_TO(from, to); -+ } else { -+ HASH_FROM_TO(from, HASH_STRENGTH_FULL); -+ HASH_FROM_TO(0, to - HASH_STRENGTH_FULL); -+ } -+ } else { -+ if (from <= HASH_STRENGTH_FULL) { -+ HASH_FROM_DOWN_TO(from, to); -+ } else if (to >= HASH_STRENGTH_FULL) { -+ from -= HASH_STRENGTH_FULL; -+ to -= HASH_STRENGTH_FULL; -+ HASH_FROM_DOWN_TO(from, to); -+ } else { -+ HASH_FROM_DOWN_TO(from - HASH_STRENGTH_FULL, 0); -+ HASH_FROM_DOWN_TO(HASH_STRENGTH_FULL, to); -+ } -+ } -+ -+ return hash; -+} -+ -+ -+ -+ -+#define CAN_OVERFLOW_U64(x, delta) (U64_MAX - (x) < (delta)) -+ -+/** -+ * -+ * Called when: rshash_pos or rshash_neg is about to overflow or a scan round -+ * has finished. -+ * -+ * return 0 if no page has been scanned since last call, 1 otherwise. -+ */ -+static inline int encode_benefit(void) -+{ -+ u64 scanned_delta, pos_delta, neg_delta; -+ unsigned long base = benefit.base; -+ -+ scanned_delta = uksm_pages_scanned - uksm_pages_scanned_last; -+ -+ if (!scanned_delta) -+ return 0; -+ -+ scanned_delta >>= base; -+ pos_delta = rshash_pos >> base; -+ neg_delta = rshash_neg >> base; -+ -+ if (CAN_OVERFLOW_U64(benefit.pos, pos_delta) || -+ CAN_OVERFLOW_U64(benefit.neg, neg_delta) || -+ CAN_OVERFLOW_U64(benefit.scanned, scanned_delta)) { -+ benefit.scanned >>= 1; -+ benefit.neg >>= 1; -+ benefit.pos >>= 1; -+ benefit.base++; -+ scanned_delta >>= 1; -+ pos_delta >>= 1; -+ neg_delta >>= 1; -+ } -+ -+ benefit.pos += pos_delta; -+ benefit.neg += neg_delta; -+ benefit.scanned += scanned_delta; -+ -+ BUG_ON(!benefit.scanned); -+ -+ rshash_pos = rshash_neg = 0; -+ uksm_pages_scanned_last = uksm_pages_scanned; -+ -+ return 1; -+} -+ -+static inline void reset_benefit(void) -+{ -+ benefit.pos = 0; -+ benefit.neg = 0; -+ benefit.base = 0; -+ benefit.scanned = 0; -+} -+ -+static inline void inc_rshash_pos(unsigned long delta) -+{ -+ if (CAN_OVERFLOW_U64(rshash_pos, delta)) -+ encode_benefit(); -+ -+ rshash_pos += delta; -+} -+ -+static inline void inc_rshash_neg(unsigned long delta) -+{ -+ if (CAN_OVERFLOW_U64(rshash_neg, delta)) -+ encode_benefit(); -+ -+ rshash_neg += delta; -+} -+ -+ -+static inline u32 page_hash(struct page *page, unsigned long hash_strength, -+ int cost_accounting) -+{ -+ u32 val; -+ unsigned long delta; -+ -+ void *addr = kmap_atomic(page); -+ -+ val = random_sample_hash(addr, hash_strength); -+ kunmap_atomic(addr); -+ -+ if (cost_accounting) { -+ if (HASH_STRENGTH_FULL > hash_strength) -+ delta = HASH_STRENGTH_FULL - hash_strength; -+ else -+ delta = 0; -+ -+ inc_rshash_pos(delta); -+ } -+ -+ return val; -+} -+ -+static int memcmp_pages(struct page *page1, struct page *page2, -+ int cost_accounting) -+{ -+ char *addr1, *addr2; -+ int ret; -+ -+ addr1 = kmap_atomic(page1); -+ addr2 = kmap_atomic(page2); -+ ret = memcmp(addr1, addr2, PAGE_SIZE); -+ kunmap_atomic(addr2); -+ kunmap_atomic(addr1); -+ -+ if (cost_accounting) -+ inc_rshash_neg(memcmp_cost); -+ -+ return ret; -+} -+ -+static inline int pages_identical(struct page *page1, struct page *page2) -+{ -+ return !memcmp_pages(page1, page2, 0); -+} -+ -+static inline int is_page_full_zero(struct page *page) -+{ -+ char *addr; -+ int ret; -+ -+ addr = kmap_atomic(page); -+ ret = is_full_zero(addr, PAGE_SIZE); -+ kunmap_atomic(addr); -+ -+ return ret; -+} -+ -+static int write_protect_page(struct vm_area_struct *vma, struct page *page, -+ pte_t *orig_pte, pte_t *old_pte) -+{ -+ struct mm_struct *mm = vma->vm_mm; -+ unsigned long addr; -+ pte_t *ptep; -+ spinlock_t *ptl; -+ int swapped; -+ int err = -EFAULT; -+ unsigned long mmun_start; /* For mmu_notifiers */ -+ unsigned long mmun_end; /* For mmu_notifiers */ -+ -+ addr = page_address_in_vma(page, vma); -+ if (addr == -EFAULT) -+ goto out; -+ -+ BUG_ON(PageTransCompound(page)); -+ -+ mmun_start = addr; -+ mmun_end = addr + PAGE_SIZE; -+ mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); -+ -+ ptep = page_check_address(page, mm, addr, &ptl, 0); -+ if (!ptep) -+ goto out_mn; -+ -+ if (old_pte) -+ *old_pte = *ptep; -+ -+ if (pte_write(*ptep) || pte_dirty(*ptep)) { -+ pte_t entry; -+ -+ swapped = PageSwapCache(page); -+ flush_cache_page(vma, addr, page_to_pfn(page)); -+ /* -+ * Ok this is tricky, when get_user_pages_fast() run it doesnt -+ * take any lock, therefore the check that we are going to make -+ * with the pagecount against the mapcount is racey and -+ * O_DIRECT can happen right after the check. -+ * So we clear the pte and flush the tlb before the check -+ * this assure us that no O_DIRECT can happen after the check -+ * or in the middle of the check. -+ */ -+ entry = ptep_clear_flush(vma, addr, ptep); -+ /* -+ * Check that no O_DIRECT or similar I/O is in progress on the -+ * page -+ */ -+ if (page_mapcount(page) + 1 + swapped != page_count(page)) { -+ set_pte_at(mm, addr, ptep, entry); -+ goto out_unlock; -+ } -+ if (pte_dirty(entry)) -+ set_page_dirty(page); -+ entry = pte_mkclean(pte_wrprotect(entry)); -+ set_pte_at_notify(mm, addr, ptep, entry); -+ } -+ *orig_pte = *ptep; -+ err = 0; -+ -+out_unlock: -+ pte_unmap_unlock(ptep, ptl); -+out_mn: -+ mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); -+out: -+ return err; -+} -+ -+#define MERGE_ERR_PGERR 1 /* the page is invalid cannot continue */ -+#define MERGE_ERR_COLLI 2 /* there is a collision */ -+#define MERGE_ERR_COLLI_MAX 3 /* collision at the max hash strength */ -+#define MERGE_ERR_CHANGED 4 /* the page has changed since last hash */ -+ -+ -+/** -+ * replace_page - replace page in vma by new ksm page -+ * @vma: vma that holds the pte pointing to page -+ * @page: the page we are replacing by kpage -+ * @kpage: the ksm page we replace page by -+ * @orig_pte: the original value of the pte -+ * -+ * Returns 0 on success, MERGE_ERR_PGERR on failure. -+ */ -+static int replace_page(struct vm_area_struct *vma, struct page *page, -+ struct page *kpage, pte_t orig_pte) -+{ -+ struct mm_struct *mm = vma->vm_mm; -+ pgd_t *pgd; -+ pud_t *pud; -+ pmd_t *pmd; -+ pte_t *ptep; -+ spinlock_t *ptl; -+ pte_t entry; -+ -+ unsigned long addr; -+ int err = MERGE_ERR_PGERR; -+ unsigned long mmun_start; /* For mmu_notifiers */ -+ unsigned long mmun_end; /* For mmu_notifiers */ -+ -+ addr = page_address_in_vma(page, vma); -+ if (addr == -EFAULT) -+ goto out; -+ -+ pgd = pgd_offset(mm, addr); -+ if (!pgd_present(*pgd)) -+ goto out; -+ -+ pud = pud_offset(pgd, addr); -+ if (!pud_present(*pud)) -+ goto out; -+ -+ pmd = pmd_offset(pud, addr); -+ BUG_ON(pmd_trans_huge(*pmd)); -+ if (!pmd_present(*pmd)) -+ goto out; -+ -+ mmun_start = addr; -+ mmun_end = addr + PAGE_SIZE; -+ mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end); -+ -+ ptep = pte_offset_map_lock(mm, pmd, addr, &ptl); -+ if (!pte_same(*ptep, orig_pte)) { -+ pte_unmap_unlock(ptep, ptl); -+ goto out_mn; -+ } -+ -+ flush_cache_page(vma, addr, pte_pfn(*ptep)); -+ ptep_clear_flush(vma, addr, ptep); -+ entry = mk_pte(kpage, vma->vm_page_prot); -+ -+ /* special treatment is needed for zero_page */ -+ if ((page_to_pfn(kpage) == uksm_zero_pfn) || -+ (page_to_pfn(kpage) == zero_pfn)) -+ entry = pte_mkspecial(entry); -+ else { -+ get_page(kpage); -+ page_add_anon_rmap(kpage, vma, addr); -+ } -+ -+ set_pte_at_notify(mm, addr, ptep, entry); -+ -+ page_remove_rmap(page); -+ if (!page_mapped(page)) -+ try_to_free_swap(page); -+ put_page(page); -+ -+ pte_unmap_unlock(ptep, ptl); -+ err = 0; -+out_mn: -+ mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end); -+out: -+ return err; -+} -+ -+ -+/** -+ * Fully hash a page with HASH_STRENGTH_MAX return a non-zero hash value. The -+ * zero hash value at HASH_STRENGTH_MAX is used to indicated that its -+ * hash_max member has not been calculated. -+ * -+ * @page The page needs to be hashed -+ * @hash_old The hash value calculated with current hash strength -+ * -+ * return the new hash value calculated at HASH_STRENGTH_MAX -+ */ -+static inline u32 page_hash_max(struct page *page, u32 hash_old) -+{ -+ u32 hash_max = 0; -+ void *addr; -+ -+ addr = kmap_atomic(page); -+ hash_max = delta_hash(addr, hash_strength, -+ HASH_STRENGTH_MAX, hash_old); -+ -+ kunmap_atomic(addr); -+ -+ if (!hash_max) -+ hash_max = 1; -+ -+ inc_rshash_neg(HASH_STRENGTH_MAX - hash_strength); -+ return hash_max; -+} -+ -+/* -+ * We compare the hash again, to ensure that it is really a hash collision -+ * instead of being caused by page write. -+ */ -+static inline int check_collision(struct rmap_item *rmap_item, -+ u32 hash) -+{ -+ int err; -+ struct page *page = rmap_item->page; -+ -+ /* if this rmap_item has already been hash_maxed, then the collision -+ * must appears in the second-level rbtree search. In this case we check -+ * if its hash_max value has been changed. Otherwise, the collision -+ * happens in the first-level rbtree search, so we check against it's -+ * current hash value. -+ */ -+ if (rmap_item->hash_max) { -+ inc_rshash_neg(memcmp_cost); -+ inc_rshash_neg(HASH_STRENGTH_MAX - hash_strength); -+ -+ if (rmap_item->hash_max == page_hash_max(page, hash)) -+ err = MERGE_ERR_COLLI; -+ else -+ err = MERGE_ERR_CHANGED; -+ } else { -+ inc_rshash_neg(memcmp_cost + hash_strength); -+ -+ if (page_hash(page, hash_strength, 0) == hash) -+ err = MERGE_ERR_COLLI; -+ else -+ err = MERGE_ERR_CHANGED; -+ } -+ -+ return err; -+} -+ -+static struct page *page_trans_compound_anon(struct page *page) -+{ -+ if (PageTransCompound(page)) { -+ struct page *head = compound_trans_head(page); -+ /* -+ * head may actually be splitted and freed from under -+ * us but it's ok here. -+ */ -+ if (PageAnon(head)) -+ return head; -+ } -+ return NULL; -+} -+ -+static int page_trans_compound_anon_split(struct page *page) -+{ -+ int ret = 0; -+ struct page *transhuge_head = page_trans_compound_anon(page); -+ if (transhuge_head) { -+ /* Get the reference on the head to split it. */ -+ if (get_page_unless_zero(transhuge_head)) { -+ /* -+ * Recheck we got the reference while the head -+ * was still anonymous. -+ */ -+ if (PageAnon(transhuge_head)) -+ ret = split_huge_page(transhuge_head); -+ else -+ /* -+ * Retry later if split_huge_page run -+ * from under us. -+ */ -+ ret = 1; -+ put_page(transhuge_head); -+ } else -+ /* Retry later if split_huge_page run from under us. */ -+ ret = 1; -+ } -+ return ret; -+} -+ -+/** -+ * Try to merge a rmap_item.page with a kpage in stable node. kpage must -+ * already be a ksm page. -+ * -+ * @return 0 if the pages were merged, -EFAULT otherwise. -+ */ -+static int try_to_merge_with_uksm_page(struct rmap_item *rmap_item, -+ struct page *kpage, u32 hash) -+{ -+ struct vm_area_struct *vma = rmap_item->slot->vma; -+ struct mm_struct *mm = vma->vm_mm; -+ pte_t orig_pte = __pte(0); -+ int err = MERGE_ERR_PGERR; -+ struct page *page; -+ -+ if (uksm_test_exit(mm)) -+ goto out; -+ -+ page = rmap_item->page; -+ -+ if (page == kpage) { /* ksm page forked */ -+ err = 0; -+ goto out; -+ } -+ -+ if (PageTransCompound(page) && page_trans_compound_anon_split(page)) -+ goto out; -+ BUG_ON(PageTransCompound(page)); -+ -+ if (!PageAnon(page) || !PageKsm(kpage)) -+ goto out; -+ -+ /* -+ * We need the page lock to read a stable PageSwapCache in -+ * write_protect_page(). We use trylock_page() instead of -+ * lock_page() because we don't want to wait here - we -+ * prefer to continue scanning and merging different pages, -+ * then come back to this page when it is unlocked. -+ */ -+ if (!trylock_page(page)) -+ goto out; -+ /* -+ * If this anonymous page is mapped only here, its pte may need -+ * to be write-protected. If it's mapped elsewhere, all of its -+ * ptes are necessarily already write-protected. But in either -+ * case, we need to lock and check page_count is not raised. -+ */ -+ if (write_protect_page(vma, page, &orig_pte, NULL) == 0) { -+ if (pages_identical(page, kpage)) -+ err = replace_page(vma, page, kpage, orig_pte); -+ else -+ err = check_collision(rmap_item, hash); -+ } -+ -+ if ((vma->vm_flags & VM_LOCKED) && kpage && !err) { -+ munlock_vma_page(page); -+ if (!PageMlocked(kpage)) { -+ unlock_page(page); -+ lock_page(kpage); -+ mlock_vma_page(kpage); -+ page = kpage; /* for final unlock */ -+ } -+ } -+ -+ unlock_page(page); -+out: -+ return err; -+} -+ -+ -+ -+/** -+ * If two pages fail to merge in try_to_merge_two_pages, then we have a chance -+ * to restore a page mapping that has been changed in try_to_merge_two_pages. -+ * -+ * @return 0 on success. -+ */ -+static int restore_uksm_page_pte(struct vm_area_struct *vma, unsigned long addr, -+ pte_t orig_pte, pte_t wprt_pte) -+{ -+ struct mm_struct *mm = vma->vm_mm; -+ pgd_t *pgd; -+ pud_t *pud; -+ pmd_t *pmd; -+ pte_t *ptep; -+ spinlock_t *ptl; -+ -+ int err = -EFAULT; -+ -+ pgd = pgd_offset(mm, addr); -+ if (!pgd_present(*pgd)) -+ goto out; -+ -+ pud = pud_offset(pgd, addr); -+ if (!pud_present(*pud)) -+ goto out; -+ -+ pmd = pmd_offset(pud, addr); -+ if (!pmd_present(*pmd)) -+ goto out; -+ -+ ptep = pte_offset_map_lock(mm, pmd, addr, &ptl); -+ if (!pte_same(*ptep, wprt_pte)) { -+ /* already copied, let it be */ -+ pte_unmap_unlock(ptep, ptl); -+ goto out; -+ } -+ -+ /* -+ * Good boy, still here. When we still get the ksm page, it does not -+ * return to the free page pool, there is no way that a pte was changed -+ * to other page and gets back to this page. And remind that ksm page -+ * do not reuse in do_wp_page(). So it's safe to restore the original -+ * pte. -+ */ -+ flush_cache_page(vma, addr, pte_pfn(*ptep)); -+ ptep_clear_flush(vma, addr, ptep); -+ set_pte_at_notify(mm, addr, ptep, orig_pte); -+ -+ pte_unmap_unlock(ptep, ptl); -+ err = 0; -+out: -+ return err; -+} -+ -+/** -+ * try_to_merge_two_pages() - take two identical pages and prepare -+ * them to be merged into one page(rmap_item->page) -+ * -+ * @return 0 if we successfully merged two identical pages into -+ * one ksm page. MERGE_ERR_COLLI if it's only a hash collision -+ * search in rbtree. MERGE_ERR_CHANGED if rmap_item has been -+ * changed since it's hashed. MERGE_ERR_PGERR otherwise. -+ * -+ */ -+static int try_to_merge_two_pages(struct rmap_item *rmap_item, -+ struct rmap_item *tree_rmap_item, -+ u32 hash) -+{ -+ pte_t orig_pte1 = __pte(0), orig_pte2 = __pte(0); -+ pte_t wprt_pte1 = __pte(0), wprt_pte2 = __pte(0); -+ struct vm_area_struct *vma1 = rmap_item->slot->vma; -+ struct vm_area_struct *vma2 = tree_rmap_item->slot->vma; -+ struct page *page = rmap_item->page; -+ struct page *tree_page = tree_rmap_item->page; -+ int err = MERGE_ERR_PGERR; -+ struct address_space *saved_mapping; -+ -+ -+ if (rmap_item->page == tree_rmap_item->page) -+ goto out; -+ -+ if (PageTransCompound(page) && page_trans_compound_anon_split(page)) -+ goto out; -+ BUG_ON(PageTransCompound(page)); -+ -+ if (PageTransCompound(tree_page) && page_trans_compound_anon_split(tree_page)) -+ goto out; -+ BUG_ON(PageTransCompound(tree_page)); -+ -+ if (!PageAnon(page) || !PageAnon(tree_page)) -+ goto out; -+ -+ if (!trylock_page(page)) -+ goto out; -+ -+ -+ if (write_protect_page(vma1, page, &wprt_pte1, &orig_pte1) != 0) { -+ unlock_page(page); -+ goto out; -+ } -+ -+ /* -+ * While we hold page lock, upgrade page from -+ * PageAnon+anon_vma to PageKsm+NULL stable_node: -+ * stable_tree_insert() will update stable_node. -+ */ -+ saved_mapping = page->mapping; -+ set_page_stable_node(page, NULL); -+ mark_page_accessed(page); -+ unlock_page(page); -+ -+ if (!trylock_page(tree_page)) -+ goto restore_out; -+ -+ if (write_protect_page(vma2, tree_page, &wprt_pte2, &orig_pte2) != 0) { -+ unlock_page(tree_page); -+ goto restore_out; -+ } -+ -+ if (pages_identical(page, tree_page)) { -+ err = replace_page(vma2, tree_page, page, wprt_pte2); -+ if (err) { -+ unlock_page(tree_page); -+ goto restore_out; -+ } -+ -+ if ((vma2->vm_flags & VM_LOCKED)) { -+ munlock_vma_page(tree_page); -+ if (!PageMlocked(page)) { -+ unlock_page(tree_page); -+ lock_page(page); -+ mlock_vma_page(page); -+ tree_page = page; /* for final unlock */ -+ } -+ } -+ -+ unlock_page(tree_page); -+ -+ goto out; /* success */ -+ -+ } else { -+ if (tree_rmap_item->hash_max && -+ tree_rmap_item->hash_max == rmap_item->hash_max) { -+ err = MERGE_ERR_COLLI_MAX; -+ } else if (page_hash(page, hash_strength, 0) == -+ page_hash(tree_page, hash_strength, 0)) { -+ inc_rshash_neg(memcmp_cost + hash_strength * 2); -+ err = MERGE_ERR_COLLI; -+ } else { -+ err = MERGE_ERR_CHANGED; -+ } -+ -+ unlock_page(tree_page); -+ } -+ -+restore_out: -+ lock_page(page); -+ if (!restore_uksm_page_pte(vma1, get_rmap_addr(rmap_item), -+ orig_pte1, wprt_pte1)) -+ page->mapping = saved_mapping; -+ -+ unlock_page(page); -+out: -+ return err; -+} -+ -+static inline int hash_cmp(u32 new_val, u32 node_val) -+{ -+ if (new_val > node_val) -+ return 1; -+ else if (new_val < node_val) -+ return -1; -+ else -+ return 0; -+} -+ -+static inline u32 rmap_item_hash_max(struct rmap_item *item, u32 hash) -+{ -+ u32 hash_max = item->hash_max; -+ -+ if (!hash_max) { -+ hash_max = page_hash_max(item->page, hash); -+ -+ item->hash_max = hash_max; -+ } -+ -+ return hash_max; -+} -+ -+ -+ -+/** -+ * stable_tree_search() - search the stable tree for a page -+ * -+ * @item: the rmap_item we are comparing with -+ * @hash: the hash value of this item->page already calculated -+ * -+ * @return the page we have found, NULL otherwise. The page returned has -+ * been gotten. -+ */ -+static struct page *stable_tree_search(struct rmap_item *item, u32 hash) -+{ -+ struct rb_node *node = root_stable_treep->rb_node; -+ struct tree_node *tree_node; -+ unsigned long hash_max; -+ struct page *page = item->page; -+ struct stable_node *stable_node; -+ -+ stable_node = page_stable_node(page); -+ if (stable_node) { -+ /* ksm page forked, that is -+ * if (PageKsm(page) && !in_stable_tree(rmap_item)) -+ * it's actually gotten once outside. -+ */ -+ get_page(page); -+ return page; -+ } -+ -+ while (node) { -+ int cmp; -+ -+ tree_node = rb_entry(node, struct tree_node, node); -+ -+ cmp = hash_cmp(hash, tree_node->hash); -+ -+ if (cmp < 0) -+ node = node->rb_left; -+ else if (cmp > 0) -+ node = node->rb_right; -+ else -+ break; -+ } -+ -+ if (!node) -+ return NULL; -+ -+ if (tree_node->count == 1) { -+ stable_node = rb_entry(tree_node->sub_root.rb_node, -+ struct stable_node, node); -+ BUG_ON(!stable_node); -+ -+ goto get_page_out; -+ } -+ -+ /* -+ * ok, we have to search the second -+ * level subtree, hash the page to a -+ * full strength. -+ */ -+ node = tree_node->sub_root.rb_node; -+ BUG_ON(!node); -+ hash_max = rmap_item_hash_max(item, hash); -+ -+ while (node) { -+ int cmp; -+ -+ stable_node = rb_entry(node, struct stable_node, node); -+ -+ cmp = hash_cmp(hash_max, stable_node->hash_max); -+ -+ if (cmp < 0) -+ node = node->rb_left; -+ else if (cmp > 0) -+ node = node->rb_right; -+ else -+ goto get_page_out; -+ } -+ -+ return NULL; -+ -+get_page_out: -+ page = get_uksm_page(stable_node, 1, 1); -+ return page; -+} -+ -+static int try_merge_rmap_item(struct rmap_item *item, -+ struct page *kpage, -+ struct page *tree_page) -+{ -+ spinlock_t *ptl; -+ pte_t *ptep; -+ unsigned long addr; -+ struct vm_area_struct *vma = item->slot->vma; -+ -+ addr = get_rmap_addr(item); -+ ptep = page_check_address(kpage, vma->vm_mm, addr, &ptl, 0); -+ if (!ptep) -+ return 0; -+ -+ if (pte_write(*ptep)) { -+ /* has changed, abort! */ -+ pte_unmap_unlock(ptep, ptl); -+ return 0; -+ } -+ -+ get_page(tree_page); -+ page_add_anon_rmap(tree_page, vma, addr); -+ -+ flush_cache_page(vma, addr, pte_pfn(*ptep)); -+ ptep_clear_flush(vma, addr, ptep); -+ set_pte_at_notify(vma->vm_mm, addr, ptep, -+ mk_pte(tree_page, vma->vm_page_prot)); -+ -+ page_remove_rmap(kpage); -+ put_page(kpage); -+ -+ pte_unmap_unlock(ptep, ptl); -+ -+ return 1; -+} -+ -+/** -+ * try_to_merge_with_stable_page() - when two rmap_items need to be inserted -+ * into stable tree, the page was found to be identical to a stable ksm page, -+ * this is the last chance we can merge them into one. -+ * -+ * @item1: the rmap_item holding the page which we wanted to insert -+ * into stable tree. -+ * @item2: the other rmap_item we found when unstable tree search -+ * @oldpage: the page currently mapped by the two rmap_items -+ * @tree_page: the page we found identical in stable tree node -+ * @success1: return if item1 is successfully merged -+ * @success2: return if item2 is successfully merged -+ */ -+static void try_merge_with_stable(struct rmap_item *item1, -+ struct rmap_item *item2, -+ struct page **kpage, -+ struct page *tree_page, -+ int *success1, int *success2) -+{ -+ struct vm_area_struct *vma1 = item1->slot->vma; -+ struct vm_area_struct *vma2 = item2->slot->vma; -+ *success1 = 0; -+ *success2 = 0; -+ -+ if (unlikely(*kpage == tree_page)) { -+ /* I don't think this can really happen */ -+ printk(KERN_WARNING "UKSM: unexpected condition detected in " -+ "try_merge_with_stable() -- *kpage == tree_page !\n"); -+ *success1 = 1; -+ *success2 = 1; -+ return; -+ } -+ -+ if (!PageAnon(*kpage) || !PageKsm(*kpage)) -+ goto failed; -+ -+ if (!trylock_page(tree_page)) -+ goto failed; -+ -+ /* If the oldpage is still ksm and still pointed -+ * to in the right place, and still write protected, -+ * we are confident it's not changed, no need to -+ * memcmp anymore. -+ * be ware, we cannot take nested pte locks, -+ * deadlock risk. -+ */ -+ if (!try_merge_rmap_item(item1, *kpage, tree_page)) -+ goto unlock_failed; -+ -+ /* ok, then vma2, remind that pte1 already set */ -+ if (!try_merge_rmap_item(item2, *kpage, tree_page)) -+ goto success_1; -+ -+ *success2 = 1; -+success_1: -+ *success1 = 1; -+ -+ -+ if ((*success1 && vma1->vm_flags & VM_LOCKED) || -+ (*success2 && vma2->vm_flags & VM_LOCKED)) { -+ munlock_vma_page(*kpage); -+ if (!PageMlocked(tree_page)) -+ mlock_vma_page(tree_page); -+ } -+ -+ /* -+ * We do not need oldpage any more in the caller, so can break the lock -+ * now. -+ */ -+ unlock_page(*kpage); -+ *kpage = tree_page; /* Get unlocked outside. */ -+ return; -+ -+unlock_failed: -+ unlock_page(tree_page); -+failed: -+ return; -+} -+ -+static inline void stable_node_hash_max(struct stable_node *node, -+ struct page *page, u32 hash) -+{ -+ u32 hash_max = node->hash_max; -+ -+ if (!hash_max) { -+ hash_max = page_hash_max(page, hash); -+ node->hash_max = hash_max; -+ } -+} -+ -+static inline -+struct stable_node *new_stable_node(struct tree_node *tree_node, -+ struct page *kpage, u32 hash_max) -+{ -+ struct stable_node *new_stable_node; -+ -+ new_stable_node = alloc_stable_node(); -+ if (!new_stable_node) -+ return NULL; -+ -+ new_stable_node->kpfn = page_to_pfn(kpage); -+ new_stable_node->hash_max = hash_max; -+ new_stable_node->tree_node = tree_node; -+ set_page_stable_node(kpage, new_stable_node); -+ -+ return new_stable_node; -+} -+ -+static inline -+struct stable_node *first_level_insert(struct tree_node *tree_node, -+ struct rmap_item *rmap_item, -+ struct rmap_item *tree_rmap_item, -+ struct page **kpage, u32 hash, -+ int *success1, int *success2) -+{ -+ int cmp; -+ struct page *tree_page; -+ u32 hash_max = 0; -+ struct stable_node *stable_node, *new_snode; -+ struct rb_node *parent = NULL, **new; -+ -+ /* this tree node contains no sub-tree yet */ -+ stable_node = rb_entry(tree_node->sub_root.rb_node, -+ struct stable_node, node); -+ -+ tree_page = get_uksm_page(stable_node, 1, 0); -+ if (tree_page) { -+ cmp = memcmp_pages(*kpage, tree_page, 1); -+ if (!cmp) { -+ try_merge_with_stable(rmap_item, tree_rmap_item, kpage, -+ tree_page, success1, success2); -+ put_page(tree_page); -+ if (!*success1 && !*success2) -+ goto failed; -+ -+ return stable_node; -+ -+ } else { -+ /* -+ * collision in first level try to create a subtree. -+ * A new node need to be created. -+ */ -+ put_page(tree_page); -+ -+ stable_node_hash_max(stable_node, tree_page, -+ tree_node->hash); -+ hash_max = rmap_item_hash_max(rmap_item, hash); -+ cmp = hash_cmp(hash_max, stable_node->hash_max); -+ -+ parent = &stable_node->node; -+ if (cmp < 0) { -+ new = &parent->rb_left; -+ } else if (cmp > 0) { -+ new = &parent->rb_right; -+ } else { -+ goto failed; -+ } -+ } -+ -+ } else { -+ /* the only stable_node deleted, we reuse its tree_node. -+ */ -+ parent = NULL; -+ new = &tree_node->sub_root.rb_node; -+ } -+ -+ new_snode = new_stable_node(tree_node, *kpage, hash_max); -+ if (!new_snode) -+ goto failed; -+ -+ rb_link_node(&new_snode->node, parent, new); -+ rb_insert_color(&new_snode->node, &tree_node->sub_root); -+ tree_node->count++; -+ *success1 = *success2 = 1; -+ -+ return new_snode; -+ -+failed: -+ return NULL; -+} -+ -+static inline -+struct stable_node *stable_subtree_insert(struct tree_node *tree_node, -+ struct rmap_item *rmap_item, -+ struct rmap_item *tree_rmap_item, -+ struct page **kpage, u32 hash, -+ int *success1, int *success2) -+{ -+ struct page *tree_page; -+ u32 hash_max; -+ struct stable_node *stable_node, *new_snode; -+ struct rb_node *parent, **new; -+ -+research: -+ parent = NULL; -+ new = &tree_node->sub_root.rb_node; -+ BUG_ON(!*new); -+ hash_max = rmap_item_hash_max(rmap_item, hash); -+ while (*new) { -+ int cmp; -+ -+ stable_node = rb_entry(*new, struct stable_node, node); -+ -+ cmp = hash_cmp(hash_max, stable_node->hash_max); -+ -+ if (cmp < 0) { -+ parent = *new; -+ new = &parent->rb_left; -+ } else if (cmp > 0) { -+ parent = *new; -+ new = &parent->rb_right; -+ } else { -+ tree_page = get_uksm_page(stable_node, 1, 0); -+ if (tree_page) { -+ cmp = memcmp_pages(*kpage, tree_page, 1); -+ if (!cmp) { -+ try_merge_with_stable(rmap_item, -+ tree_rmap_item, kpage, -+ tree_page, success1, success2); -+ -+ put_page(tree_page); -+ if (!*success1 && !*success2) -+ goto failed; -+ /* -+ * successfully merged with a stable -+ * node -+ */ -+ return stable_node; -+ } else { -+ put_page(tree_page); -+ goto failed; -+ } -+ } else { -+ /* -+ * stable node may be deleted, -+ * and subtree maybe -+ * restructed, cannot -+ * continue, research it. -+ */ -+ if (tree_node->count) { -+ goto research; -+ } else { -+ /* reuse the tree node*/ -+ parent = NULL; -+ new = &tree_node->sub_root.rb_node; -+ } -+ } -+ } -+ } -+ -+ new_snode = new_stable_node(tree_node, *kpage, hash_max); -+ if (!new_snode) -+ goto failed; -+ -+ rb_link_node(&new_snode->node, parent, new); -+ rb_insert_color(&new_snode->node, &tree_node->sub_root); -+ tree_node->count++; -+ *success1 = *success2 = 1; -+ -+ return new_snode; -+ -+failed: -+ return NULL; -+} -+ -+ -+/** -+ * stable_tree_insert() - try to insert a merged page in unstable tree to -+ * the stable tree -+ * -+ * @kpage: the page need to be inserted -+ * @hash: the current hash of this page -+ * @rmap_item: the rmap_item being scanned -+ * @tree_rmap_item: the rmap_item found on unstable tree -+ * @success1: return if rmap_item is merged -+ * @success2: return if tree_rmap_item is merged -+ * -+ * @return the stable_node on stable tree if at least one -+ * rmap_item is inserted into stable tree, NULL -+ * otherwise. -+ */ -+static struct stable_node * -+stable_tree_insert(struct page **kpage, u32 hash, -+ struct rmap_item *rmap_item, -+ struct rmap_item *tree_rmap_item, -+ int *success1, int *success2) -+{ -+ struct rb_node **new = &root_stable_treep->rb_node; -+ struct rb_node *parent = NULL; -+ struct stable_node *stable_node; -+ struct tree_node *tree_node; -+ u32 hash_max = 0; -+ -+ *success1 = *success2 = 0; -+ -+ while (*new) { -+ int cmp; -+ -+ tree_node = rb_entry(*new, struct tree_node, node); -+ -+ cmp = hash_cmp(hash, tree_node->hash); -+ -+ if (cmp < 0) { -+ parent = *new; -+ new = &parent->rb_left; -+ } else if (cmp > 0) { -+ parent = *new; -+ new = &parent->rb_right; -+ } else -+ break; -+ } -+ -+ if (*new) { -+ if (tree_node->count == 1) { -+ stable_node = first_level_insert(tree_node, rmap_item, -+ tree_rmap_item, kpage, -+ hash, success1, success2); -+ } else { -+ stable_node = stable_subtree_insert(tree_node, -+ rmap_item, tree_rmap_item, kpage, -+ hash, success1, success2); -+ } -+ } else { -+ -+ /* no tree node found */ -+ tree_node = alloc_tree_node(stable_tree_node_listp); -+ if (!tree_node) { -+ stable_node = NULL; -+ goto out; -+ } -+ -+ stable_node = new_stable_node(tree_node, *kpage, hash_max); -+ if (!stable_node) { -+ free_tree_node(tree_node); -+ goto out; -+ } -+ -+ tree_node->hash = hash; -+ rb_link_node(&tree_node->node, parent, new); -+ rb_insert_color(&tree_node->node, root_stable_treep); -+ parent = NULL; -+ new = &tree_node->sub_root.rb_node; -+ -+ rb_link_node(&stable_node->node, parent, new); -+ rb_insert_color(&stable_node->node, &tree_node->sub_root); -+ tree_node->count++; -+ *success1 = *success2 = 1; -+ } -+ -+out: -+ return stable_node; -+} -+ -+ -+/** -+ * get_tree_rmap_item_page() - try to get the page and lock the mmap_sem -+ * -+ * @return 0 on success, -EBUSY if unable to lock the mmap_sem, -+ * -EINVAL if the page mapping has been changed. -+ */ -+static inline int get_tree_rmap_item_page(struct rmap_item *tree_rmap_item) -+{ -+ int err; -+ -+ err = get_mergeable_page_lock_mmap(tree_rmap_item); -+ -+ if (err == -EINVAL) { -+ /* its page map has been changed, remove it */ -+ remove_rmap_item_from_tree(tree_rmap_item); -+ } -+ -+ /* The page is gotten and mmap_sem is locked now. */ -+ return err; -+} -+ -+ -+/** -+ * unstable_tree_search_insert() - search an unstable tree rmap_item with the -+ * same hash value. Get its page and trylock the mmap_sem -+ */ -+static inline -+struct rmap_item *unstable_tree_search_insert(struct rmap_item *rmap_item, -+ u32 hash) -+ -+{ -+ struct rb_node **new = &root_unstable_tree.rb_node; -+ struct rb_node *parent = NULL; -+ struct tree_node *tree_node; -+ u32 hash_max; -+ struct rmap_item *tree_rmap_item; -+ -+ while (*new) { -+ int cmp; -+ -+ tree_node = rb_entry(*new, struct tree_node, node); -+ -+ cmp = hash_cmp(hash, tree_node->hash); -+ -+ if (cmp < 0) { -+ parent = *new; -+ new = &parent->rb_left; -+ } else if (cmp > 0) { -+ parent = *new; -+ new = &parent->rb_right; -+ } else -+ break; -+ } -+ -+ if (*new) { -+ /* got the tree_node */ -+ if (tree_node->count == 1) { -+ tree_rmap_item = rb_entry(tree_node->sub_root.rb_node, -+ struct rmap_item, node); -+ BUG_ON(!tree_rmap_item); -+ -+ goto get_page_out; -+ } -+ -+ /* well, search the collision subtree */ -+ new = &tree_node->sub_root.rb_node; -+ BUG_ON(!*new); -+ hash_max = rmap_item_hash_max(rmap_item, hash); -+ -+ while (*new) { -+ int cmp; -+ -+ tree_rmap_item = rb_entry(*new, struct rmap_item, -+ node); -+ -+ cmp = hash_cmp(hash_max, tree_rmap_item->hash_max); -+ parent = *new; -+ if (cmp < 0) -+ new = &parent->rb_left; -+ else if (cmp > 0) -+ new = &parent->rb_right; -+ else -+ goto get_page_out; -+ } -+ } else { -+ /* alloc a new tree_node */ -+ tree_node = alloc_tree_node(&unstable_tree_node_list); -+ if (!tree_node) -+ return NULL; -+ -+ tree_node->hash = hash; -+ rb_link_node(&tree_node->node, parent, new); -+ rb_insert_color(&tree_node->node, &root_unstable_tree); -+ parent = NULL; -+ new = &tree_node->sub_root.rb_node; -+ } -+ -+ /* did not found even in sub-tree */ -+ rmap_item->tree_node = tree_node; -+ rmap_item->address |= UNSTABLE_FLAG; -+ rmap_item->hash_round = uksm_hash_round; -+ rb_link_node(&rmap_item->node, parent, new); -+ rb_insert_color(&rmap_item->node, &tree_node->sub_root); -+ -+ uksm_pages_unshared++; -+ return NULL; -+ -+get_page_out: -+ if (tree_rmap_item->page == rmap_item->page) -+ return NULL; -+ -+ if (get_tree_rmap_item_page(tree_rmap_item)) -+ return NULL; -+ -+ return tree_rmap_item; -+} -+ -+static void hold_anon_vma(struct rmap_item *rmap_item, -+ struct anon_vma *anon_vma) -+{ -+ rmap_item->anon_vma = anon_vma; -+ get_anon_vma(anon_vma); -+} -+ -+ -+/** -+ * stable_tree_append() - append a rmap_item to a stable node. Deduplication -+ * ratio statistics is done in this function. -+ * -+ */ -+static void stable_tree_append(struct rmap_item *rmap_item, -+ struct stable_node *stable_node, int logdedup) -+{ -+ struct node_vma *node_vma = NULL, *new_node_vma, *node_vma_cont = NULL; -+ unsigned long key = (unsigned long)rmap_item->slot; -+ unsigned long factor = rmap_item->slot->rung->step; -+ -+ BUG_ON(!stable_node); -+ rmap_item->address |= STABLE_FLAG; -+ -+ if (hlist_empty(&stable_node->hlist)) { -+ uksm_pages_shared++; -+ goto node_vma_new; -+ } else { -+ uksm_pages_sharing++; -+ } -+ -+ hlist_for_each_entry(node_vma, &stable_node->hlist, hlist) { -+ if (node_vma->key >= key) -+ break; -+ -+ if (logdedup) { -+ node_vma->slot->pages_bemerged += factor; -+ if (list_empty(&node_vma->slot->dedup_list)) -+ list_add(&node_vma->slot->dedup_list, -+ &vma_slot_dedup); -+ } -+ } -+ -+ if (node_vma) { -+ if (node_vma->key == key) { -+ node_vma_cont = hlist_entry_safe(node_vma->hlist.next, struct node_vma, hlist); -+ goto node_vma_ok; -+ } else if (node_vma->key > key) { -+ node_vma_cont = node_vma; -+ } -+ } -+ -+node_vma_new: -+ /* no same vma already in node, alloc a new node_vma */ -+ new_node_vma = alloc_node_vma(); -+ BUG_ON(!new_node_vma); -+ new_node_vma->head = stable_node; -+ new_node_vma->slot = rmap_item->slot; -+ -+ if (!node_vma) { -+ hlist_add_head(&new_node_vma->hlist, &stable_node->hlist); -+ } else if (node_vma->key != key) { -+ if (node_vma->key < key) -+ hlist_add_after(&node_vma->hlist, &new_node_vma->hlist); -+ else { -+ hlist_add_before(&new_node_vma->hlist, -+ &node_vma->hlist); -+ } -+ -+ } -+ node_vma = new_node_vma; -+ -+node_vma_ok: /* ok, ready to add to the list */ -+ rmap_item->head = node_vma; -+ hlist_add_head(&rmap_item->hlist, &node_vma->rmap_hlist); -+ hold_anon_vma(rmap_item, rmap_item->slot->vma->anon_vma); -+ if (logdedup) { -+ rmap_item->slot->pages_merged++; -+ if (node_vma_cont) { -+ node_vma = node_vma_cont; -+ hlist_for_each_entry_continue(node_vma, hlist) { -+ node_vma->slot->pages_bemerged += factor; -+ if (list_empty(&node_vma->slot->dedup_list)) -+ list_add(&node_vma->slot->dedup_list, -+ &vma_slot_dedup); -+ } -+ } -+ } -+} -+ -+/* -+ * We use break_ksm to break COW on a ksm page: it's a stripped down -+ * -+ * if (get_user_pages(current, mm, addr, 1, 1, 1, &page, NULL) == 1) -+ * put_page(page); -+ * -+ * but taking great care only to touch a ksm page, in a VM_MERGEABLE vma, -+ * in case the application has unmapped and remapped mm,addr meanwhile. -+ * Could a ksm page appear anywhere else? Actually yes, in a VM_PFNMAP -+ * mmap of /dev/mem or /dev/kmem, where we would not want to touch it. -+ */ -+static int break_ksm(struct vm_area_struct *vma, unsigned long addr) -+{ -+ struct page *page; -+ int ret = 0; -+ -+ do { -+ cond_resched(); -+ page = follow_page(vma, addr, FOLL_GET); -+ if (IS_ERR_OR_NULL(page)) -+ break; -+ if (PageKsm(page)) { -+ ret = handle_mm_fault(vma->vm_mm, vma, addr, -+ FAULT_FLAG_WRITE); -+ } else -+ ret = VM_FAULT_WRITE; -+ put_page(page); -+ } while (!(ret & (VM_FAULT_WRITE | VM_FAULT_SIGBUS | VM_FAULT_OOM))); -+ /* -+ * We must loop because handle_mm_fault() may back out if there's -+ * any difficulty e.g. if pte accessed bit gets updated concurrently. -+ * -+ * VM_FAULT_WRITE is what we have been hoping for: it indicates that -+ * COW has been broken, even if the vma does not permit VM_WRITE; -+ * but note that a concurrent fault might break PageKsm for us. -+ * -+ * VM_FAULT_SIGBUS could occur if we race with truncation of the -+ * backing file, which also invalidates anonymous pages: that's -+ * okay, that truncation will have unmapped the PageKsm for us. -+ * -+ * VM_FAULT_OOM: at the time of writing (late July 2009), setting -+ * aside mem_cgroup limits, VM_FAULT_OOM would only be set if the -+ * current task has TIF_MEMDIE set, and will be OOM killed on return -+ * to user; and ksmd, having no mm, would never be chosen for that. -+ * -+ * But if the mm is in a limited mem_cgroup, then the fault may fail -+ * with VM_FAULT_OOM even if the current task is not TIF_MEMDIE; and -+ * even ksmd can fail in this way - though it's usually breaking ksm -+ * just to undo a merge it made a moment before, so unlikely to oom. -+ * -+ * That's a pity: we might therefore have more kernel pages allocated -+ * than we're counting as nodes in the stable tree; but uksm_do_scan -+ * will retry to break_cow on each pass, so should recover the page -+ * in due course. The important thing is to not let VM_MERGEABLE -+ * be cleared while any such pages might remain in the area. -+ */ -+ return (ret & VM_FAULT_OOM) ? -ENOMEM : 0; -+} -+ -+static void break_cow(struct rmap_item *rmap_item) -+{ -+ struct vm_area_struct *vma = rmap_item->slot->vma; -+ struct mm_struct *mm = vma->vm_mm; -+ unsigned long addr = get_rmap_addr(rmap_item); -+ -+ if (uksm_test_exit(mm)) -+ goto out; -+ -+ break_ksm(vma, addr); -+out: -+ return; -+} -+ -+/* -+ * Though it's very tempting to unmerge in_stable_tree(rmap_item)s rather -+ * than check every pte of a given vma, the locking doesn't quite work for -+ * that - an rmap_item is assigned to the stable tree after inserting ksm -+ * page and upping mmap_sem. Nor does it fit with the way we skip dup'ing -+ * rmap_items from parent to child at fork time (so as not to waste time -+ * if exit comes before the next scan reaches it). -+ * -+ * Similarly, although we'd like to remove rmap_items (so updating counts -+ * and freeing memory) when unmerging an area, it's easier to leave that -+ * to the next pass of ksmd - consider, for example, how ksmd might be -+ * in cmp_and_merge_page on one of the rmap_items we would be removing. -+ */ -+inline int unmerge_uksm_pages(struct vm_area_struct *vma, -+ unsigned long start, unsigned long end) -+{ -+ unsigned long addr; -+ int err = 0; -+ -+ for (addr = start; addr < end && !err; addr += PAGE_SIZE) { -+ if (uksm_test_exit(vma->vm_mm)) -+ break; -+ if (signal_pending(current)) -+ err = -ERESTARTSYS; -+ else -+ err = break_ksm(vma, addr); -+ } -+ return err; -+} -+ -+static inline void inc_uksm_pages_scanned(void) -+{ -+ u64 delta; -+ -+ -+ if (uksm_pages_scanned == U64_MAX) { -+ encode_benefit(); -+ -+ delta = uksm_pages_scanned >> pages_scanned_base; -+ -+ if (CAN_OVERFLOW_U64(pages_scanned_stored, delta)) { -+ pages_scanned_stored >>= 1; -+ delta >>= 1; -+ pages_scanned_base++; -+ } -+ -+ pages_scanned_stored += delta; -+ -+ uksm_pages_scanned = uksm_pages_scanned_last = 0; -+ } -+ -+ uksm_pages_scanned++; -+} -+ -+static inline int find_zero_page_hash(int strength, u32 hash) -+{ -+ return (zero_hash_table[strength] == hash); -+} -+ -+static -+int cmp_and_merge_zero_page(struct vm_area_struct *vma, struct page *page) -+{ -+ struct page *zero_page = empty_uksm_zero_page; -+ struct mm_struct *mm = vma->vm_mm; -+ pte_t orig_pte = __pte(0); -+ int err = -EFAULT; -+ -+ if (uksm_test_exit(mm)) -+ goto out; -+ -+ if (PageTransCompound(page) && page_trans_compound_anon_split(page)) -+ goto out; -+ BUG_ON(PageTransCompound(page)); -+ -+ if (!PageAnon(page)) -+ goto out; -+ -+ if (!trylock_page(page)) -+ goto out; -+ -+ if (write_protect_page(vma, page, &orig_pte, 0) == 0) { -+ if (is_page_full_zero(page)) -+ err = replace_page(vma, page, zero_page, orig_pte); -+ } -+ -+ unlock_page(page); -+out: -+ return err; -+} -+ -+/* -+ * cmp_and_merge_page() - first see if page can be merged into the stable -+ * tree; if not, compare hash to previous and if it's the same, see if page -+ * can be inserted into the unstable tree, or merged with a page already there -+ * and both transferred to the stable tree. -+ * -+ * @page: the page that we are searching identical page to. -+ * @rmap_item: the reverse mapping into the virtual address of this page -+ */ -+static void cmp_and_merge_page(struct rmap_item *rmap_item, u32 hash) -+{ -+ struct rmap_item *tree_rmap_item; -+ struct page *page; -+ struct page *kpage = NULL; -+ u32 hash_max; -+ int err; -+ unsigned int success1, success2; -+ struct stable_node *snode; -+ int cmp; -+ struct rb_node *parent = NULL, **new; -+ -+ remove_rmap_item_from_tree(rmap_item); -+ page = rmap_item->page; -+ -+ /* We first start with searching the page inside the stable tree */ -+ kpage = stable_tree_search(rmap_item, hash); -+ if (kpage) { -+ err = try_to_merge_with_uksm_page(rmap_item, kpage, -+ hash); -+ if (!err) { -+ /* -+ * The page was successfully merged, add -+ * its rmap_item to the stable tree. -+ * page lock is needed because it's -+ * racing with try_to_unmap_ksm(), etc. -+ */ -+ lock_page(kpage); -+ snode = page_stable_node(kpage); -+ stable_tree_append(rmap_item, snode, 1); -+ unlock_page(kpage); -+ put_page(kpage); -+ return; /* success */ -+ } -+ put_page(kpage); -+ -+ /* -+ * if it's a collision and it has been search in sub-rbtree -+ * (hash_max != 0), we want to abort, because if it is -+ * successfully merged in unstable tree, the collision trends to -+ * happen again. -+ */ -+ if (err == MERGE_ERR_COLLI && rmap_item->hash_max) -+ return; -+ } -+ -+ tree_rmap_item = -+ unstable_tree_search_insert(rmap_item, hash); -+ if (tree_rmap_item) { -+ err = try_to_merge_two_pages(rmap_item, tree_rmap_item, hash); -+ /* -+ * As soon as we merge this page, we want to remove the -+ * rmap_item of the page we have merged with from the unstable -+ * tree, and insert it instead as new node in the stable tree. -+ */ -+ if (!err) { -+ kpage = page; -+ remove_rmap_item_from_tree(tree_rmap_item); -+ lock_page(kpage); -+ snode = stable_tree_insert(&kpage, hash, -+ rmap_item, tree_rmap_item, -+ &success1, &success2); -+ -+ /* -+ * Do not log dedup for tree item, it's not counted as -+ * scanned in this round. -+ */ -+ if (success2) -+ stable_tree_append(tree_rmap_item, snode, 0); -+ -+ /* -+ * The order of these two stable append is important: -+ * we are scanning rmap_item. -+ */ -+ if (success1) -+ stable_tree_append(rmap_item, snode, 1); -+ -+ /* -+ * The original kpage may be unlocked inside -+ * stable_tree_insert() already. This page -+ * should be unlocked before doing -+ * break_cow(). -+ */ -+ unlock_page(kpage); -+ -+ if (!success1) -+ break_cow(rmap_item); -+ -+ if (!success2) -+ break_cow(tree_rmap_item); -+ -+ } else if (err == MERGE_ERR_COLLI) { -+ BUG_ON(tree_rmap_item->tree_node->count > 1); -+ -+ rmap_item_hash_max(tree_rmap_item, -+ tree_rmap_item->tree_node->hash); -+ -+ hash_max = rmap_item_hash_max(rmap_item, hash); -+ cmp = hash_cmp(hash_max, tree_rmap_item->hash_max); -+ parent = &tree_rmap_item->node; -+ if (cmp < 0) -+ new = &parent->rb_left; -+ else if (cmp > 0) -+ new = &parent->rb_right; -+ else -+ goto put_up_out; -+ -+ rmap_item->tree_node = tree_rmap_item->tree_node; -+ rmap_item->address |= UNSTABLE_FLAG; -+ rmap_item->hash_round = uksm_hash_round; -+ rb_link_node(&rmap_item->node, parent, new); -+ rb_insert_color(&rmap_item->node, -+ &tree_rmap_item->tree_node->sub_root); -+ rmap_item->tree_node->count++; -+ } else { -+ /* -+ * either one of the page has changed or they collide -+ * at the max hash, we consider them as ill items. -+ */ -+ remove_rmap_item_from_tree(tree_rmap_item); -+ } -+put_up_out: -+ put_page(tree_rmap_item->page); -+ up_read(&tree_rmap_item->slot->vma->vm_mm->mmap_sem); -+ } -+} -+ -+ -+ -+ -+static inline unsigned long get_pool_index(struct vma_slot *slot, -+ unsigned long index) -+{ -+ unsigned long pool_index; -+ -+ pool_index = (sizeof(struct rmap_list_entry *) * index) >> PAGE_SHIFT; -+ if (pool_index >= slot->pool_size) -+ BUG(); -+ return pool_index; -+} -+ -+static inline unsigned long index_page_offset(unsigned long index) -+{ -+ return offset_in_page(sizeof(struct rmap_list_entry *) * index); -+} -+ -+static inline -+struct rmap_list_entry *get_rmap_list_entry(struct vma_slot *slot, -+ unsigned long index, int need_alloc) -+{ -+ unsigned long pool_index; -+ struct page *page; -+ void *addr; -+ -+ -+ pool_index = get_pool_index(slot, index); -+ if (!slot->rmap_list_pool[pool_index]) { -+ if (!need_alloc) -+ return NULL; -+ -+ page = alloc_page(GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN); -+ if (!page) -+ return NULL; -+ -+ slot->rmap_list_pool[pool_index] = page; -+ } -+ -+ addr = kmap(slot->rmap_list_pool[pool_index]); -+ addr += index_page_offset(index); -+ -+ return addr; -+} -+ -+static inline void put_rmap_list_entry(struct vma_slot *slot, -+ unsigned long index) -+{ -+ unsigned long pool_index; -+ -+ pool_index = get_pool_index(slot, index); -+ BUG_ON(!slot->rmap_list_pool[pool_index]); -+ kunmap(slot->rmap_list_pool[pool_index]); -+} -+ -+static inline int entry_is_new(struct rmap_list_entry *entry) -+{ -+ return !entry->item; -+} -+ -+static inline unsigned long get_index_orig_addr(struct vma_slot *slot, -+ unsigned long index) -+{ -+ return slot->vma->vm_start + (index << PAGE_SHIFT); -+} -+ -+static inline unsigned long get_entry_address(struct rmap_list_entry *entry) -+{ -+ unsigned long addr; -+ -+ if (is_addr(entry->addr)) -+ addr = get_clean_addr(entry->addr); -+ else if (entry->item) -+ addr = get_rmap_addr(entry->item); -+ else -+ BUG(); -+ -+ return addr; -+} -+ -+static inline struct rmap_item *get_entry_item(struct rmap_list_entry *entry) -+{ -+ if (is_addr(entry->addr)) -+ return NULL; -+ -+ return entry->item; -+} -+ -+static inline void inc_rmap_list_pool_count(struct vma_slot *slot, -+ unsigned long index) -+{ -+ unsigned long pool_index; -+ -+ pool_index = get_pool_index(slot, index); -+ BUG_ON(!slot->rmap_list_pool[pool_index]); -+ slot->pool_counts[pool_index]++; -+} -+ -+static inline void dec_rmap_list_pool_count(struct vma_slot *slot, -+ unsigned long index) -+{ -+ unsigned long pool_index; -+ -+ pool_index = get_pool_index(slot, index); -+ BUG_ON(!slot->rmap_list_pool[pool_index]); -+ BUG_ON(!slot->pool_counts[pool_index]); -+ slot->pool_counts[pool_index]--; -+} -+ -+static inline int entry_has_rmap(struct rmap_list_entry *entry) -+{ -+ return !is_addr(entry->addr) && entry->item; -+} -+ -+static inline void swap_entries(struct rmap_list_entry *entry1, -+ unsigned long index1, -+ struct rmap_list_entry *entry2, -+ unsigned long index2) -+{ -+ struct rmap_list_entry tmp; -+ -+ /* swapping two new entries is meaningless */ -+ BUG_ON(entry_is_new(entry1) && entry_is_new(entry2)); -+ -+ tmp = *entry1; -+ *entry1 = *entry2; -+ *entry2 = tmp; -+ -+ if (entry_has_rmap(entry1)) -+ entry1->item->entry_index = index1; -+ -+ if (entry_has_rmap(entry2)) -+ entry2->item->entry_index = index2; -+ -+ if (entry_has_rmap(entry1) && !entry_has_rmap(entry2)) { -+ inc_rmap_list_pool_count(entry1->item->slot, index1); -+ dec_rmap_list_pool_count(entry1->item->slot, index2); -+ } else if (!entry_has_rmap(entry1) && entry_has_rmap(entry2)) { -+ inc_rmap_list_pool_count(entry2->item->slot, index2); -+ dec_rmap_list_pool_count(entry2->item->slot, index1); -+ } -+} -+ -+static inline void free_entry_item(struct rmap_list_entry *entry) -+{ -+ unsigned long index; -+ struct rmap_item *item; -+ -+ if (!is_addr(entry->addr)) { -+ BUG_ON(!entry->item); -+ item = entry->item; -+ entry->addr = get_rmap_addr(item); -+ set_is_addr(entry->addr); -+ index = item->entry_index; -+ remove_rmap_item_from_tree(item); -+ dec_rmap_list_pool_count(item->slot, index); -+ free_rmap_item(item); -+ } -+} -+ -+static inline int pool_entry_boundary(unsigned long index) -+{ -+ unsigned long linear_addr; -+ -+ linear_addr = sizeof(struct rmap_list_entry *) * index; -+ return index && !offset_in_page(linear_addr); -+} -+ -+static inline void try_free_last_pool(struct vma_slot *slot, -+ unsigned long index) -+{ -+ unsigned long pool_index; -+ -+ pool_index = get_pool_index(slot, index); -+ if (slot->rmap_list_pool[pool_index] && -+ !slot->pool_counts[pool_index]) { -+ __free_page(slot->rmap_list_pool[pool_index]); -+ slot->rmap_list_pool[pool_index] = NULL; -+ slot->flags |= UKSM_SLOT_NEED_SORT; -+ } -+ -+} -+ -+static inline unsigned long vma_item_index(struct vm_area_struct *vma, -+ struct rmap_item *item) -+{ -+ return (get_rmap_addr(item) - vma->vm_start) >> PAGE_SHIFT; -+} -+ -+static int within_same_pool(struct vma_slot *slot, -+ unsigned long i, unsigned long j) -+{ -+ unsigned long pool_i, pool_j; -+ -+ pool_i = get_pool_index(slot, i); -+ pool_j = get_pool_index(slot, j); -+ -+ return (pool_i == pool_j); -+} -+ -+static void sort_rmap_entry_list(struct vma_slot *slot) -+{ -+ unsigned long i, j; -+ struct rmap_list_entry *entry, *swap_entry; -+ -+ entry = get_rmap_list_entry(slot, 0, 0); -+ for (i = 0; i < slot->pages; ) { -+ -+ if (!entry) -+ goto skip_whole_pool; -+ -+ if (entry_is_new(entry)) -+ goto next_entry; -+ -+ if (is_addr(entry->addr)) { -+ entry->addr = 0; -+ goto next_entry; -+ } -+ -+ j = vma_item_index(slot->vma, entry->item); -+ if (j == i) -+ goto next_entry; -+ -+ if (within_same_pool(slot, i, j)) -+ swap_entry = entry + j - i; -+ else -+ swap_entry = get_rmap_list_entry(slot, j, 1); -+ -+ swap_entries(entry, i, swap_entry, j); -+ if (!within_same_pool(slot, i, j)) -+ put_rmap_list_entry(slot, j); -+ continue; -+ -+skip_whole_pool: -+ i += PAGE_SIZE / sizeof(*entry); -+ if (i < slot->pages) -+ entry = get_rmap_list_entry(slot, i, 0); -+ continue; -+ -+next_entry: -+ if (i >= slot->pages - 1 || -+ !within_same_pool(slot, i, i + 1)) { -+ put_rmap_list_entry(slot, i); -+ if (i + 1 < slot->pages) -+ entry = get_rmap_list_entry(slot, i + 1, 0); -+ } else -+ entry++; -+ i++; -+ continue; -+ } -+ -+ /* free empty pool entries which contain no rmap_item */ -+ /* CAN be simplied to based on only pool_counts when bug freed !!!!! */ -+ for (i = 0; i < slot->pool_size; i++) { -+ unsigned char has_rmap; -+ void *addr; -+ -+ if (!slot->rmap_list_pool[i]) -+ continue; -+ -+ has_rmap = 0; -+ addr = kmap(slot->rmap_list_pool[i]); -+ BUG_ON(!addr); -+ for (j = 0; j < PAGE_SIZE / sizeof(*entry); j++) { -+ entry = (struct rmap_list_entry *)addr + j; -+ if (is_addr(entry->addr)) -+ continue; -+ if (!entry->item) -+ continue; -+ has_rmap = 1; -+ } -+ kunmap(slot->rmap_list_pool[i]); -+ if (!has_rmap) { -+ BUG_ON(slot->pool_counts[i]); -+ __free_page(slot->rmap_list_pool[i]); -+ slot->rmap_list_pool[i] = NULL; -+ } -+ } -+ -+ slot->flags &= ~UKSM_SLOT_NEED_SORT; -+} -+ -+/* -+ * vma_fully_scanned() - if all the pages in this slot have been scanned. -+ */ -+static inline int vma_fully_scanned(struct vma_slot *slot) -+{ -+ return slot->pages_scanned == slot->pages; -+} -+ -+/** -+ * get_next_rmap_item() - Get the next rmap_item in a vma_slot according to -+ * its random permutation. This function is embedded with the random -+ * permutation index management code. -+ */ -+static struct rmap_item *get_next_rmap_item(struct vma_slot *slot, u32 *hash) -+{ -+ unsigned long rand_range, addr, swap_index, scan_index; -+ struct rmap_item *item = NULL; -+ struct rmap_list_entry *scan_entry, *swap_entry = NULL; -+ struct page *page; -+ -+ scan_index = swap_index = slot->pages_scanned % slot->pages; -+ -+ if (pool_entry_boundary(scan_index)) -+ try_free_last_pool(slot, scan_index - 1); -+ -+ if (vma_fully_scanned(slot)) { -+ if (slot->flags & UKSM_SLOT_NEED_SORT) -+ slot->flags |= UKSM_SLOT_NEED_RERAND; -+ else -+ slot->flags &= ~UKSM_SLOT_NEED_RERAND; -+ if (slot->flags & UKSM_SLOT_NEED_SORT) -+ sort_rmap_entry_list(slot); -+ } -+ -+ scan_entry = get_rmap_list_entry(slot, scan_index, 1); -+ if (!scan_entry) -+ return NULL; -+ -+ if (entry_is_new(scan_entry)) { -+ scan_entry->addr = get_index_orig_addr(slot, scan_index); -+ set_is_addr(scan_entry->addr); -+ } -+ -+ if (slot->flags & UKSM_SLOT_NEED_RERAND) { -+ rand_range = slot->pages - scan_index; -+ BUG_ON(!rand_range); -+ swap_index = scan_index + (prandom_u32() % rand_range); -+ } -+ -+ if (swap_index != scan_index) { -+ swap_entry = get_rmap_list_entry(slot, swap_index, 1); -+ if (entry_is_new(swap_entry)) { -+ swap_entry->addr = get_index_orig_addr(slot, -+ swap_index); -+ set_is_addr(swap_entry->addr); -+ } -+ swap_entries(scan_entry, scan_index, swap_entry, swap_index); -+ } -+ -+ addr = get_entry_address(scan_entry); -+ item = get_entry_item(scan_entry); -+ BUG_ON(addr > slot->vma->vm_end || addr < slot->vma->vm_start); -+ -+ page = follow_page(slot->vma, addr, FOLL_GET); -+ if (IS_ERR_OR_NULL(page)) -+ goto nopage; -+ -+ if (!PageAnon(page) && !page_trans_compound_anon(page)) -+ goto putpage; -+ -+ /*check is zero_page pfn or uksm_zero_page*/ -+ if ((page_to_pfn(page) == zero_pfn) -+ || (page_to_pfn(page) == uksm_zero_pfn)) -+ goto putpage; -+ -+ flush_anon_page(slot->vma, page, addr); -+ flush_dcache_page(page); -+ -+ -+ *hash = page_hash(page, hash_strength, 1); -+ inc_uksm_pages_scanned(); -+ /*if the page content all zero, re-map to zero-page*/ -+ if (find_zero_page_hash(hash_strength, *hash)) { -+ if (!cmp_and_merge_zero_page(slot->vma, page)) { -+ slot->pages_merged++; -+ __inc_zone_page_state(page, NR_UKSM_ZERO_PAGES); -+ dec_mm_counter(slot->mm, MM_ANONPAGES); -+ -+ /* For full-zero pages, no need to create rmap item */ -+ goto putpage; -+ } else { -+ inc_rshash_neg(memcmp_cost / 2); -+ } -+ } -+ -+ if (!item) { -+ item = alloc_rmap_item(); -+ if (item) { -+ /* It has already been zeroed */ -+ item->slot = slot; -+ item->address = addr; -+ item->entry_index = scan_index; -+ scan_entry->item = item; -+ inc_rmap_list_pool_count(slot, scan_index); -+ } else -+ goto putpage; -+ } -+ -+ BUG_ON(item->slot != slot); -+ /* the page may have changed */ -+ item->page = page; -+ put_rmap_list_entry(slot, scan_index); -+ if (swap_entry) -+ put_rmap_list_entry(slot, swap_index); -+ return item; -+ -+putpage: -+ put_page(page); -+ page = NULL; -+nopage: -+ /* no page, store addr back and free rmap_item if possible */ -+ free_entry_item(scan_entry); -+ put_rmap_list_entry(slot, scan_index); -+ if (swap_entry) -+ put_rmap_list_entry(slot, swap_index); -+ return NULL; -+} -+ -+static inline int in_stable_tree(struct rmap_item *rmap_item) -+{ -+ return rmap_item->address & STABLE_FLAG; -+} -+ -+/** -+ * scan_vma_one_page() - scan the next page in a vma_slot. Called with -+ * mmap_sem locked. -+ */ -+static noinline void scan_vma_one_page(struct vma_slot *slot) -+{ -+ u32 hash; -+ struct mm_struct *mm; -+ struct rmap_item *rmap_item = NULL; -+ struct vm_area_struct *vma = slot->vma; -+ -+ mm = vma->vm_mm; -+ BUG_ON(!mm); -+ BUG_ON(!slot); -+ -+ rmap_item = get_next_rmap_item(slot, &hash); -+ if (!rmap_item) -+ goto out1; -+ -+ if (PageKsm(rmap_item->page) && in_stable_tree(rmap_item)) -+ goto out2; -+ -+ cmp_and_merge_page(rmap_item, hash); -+out2: -+ put_page(rmap_item->page); -+out1: -+ slot->pages_scanned++; -+ if (slot->fully_scanned_round != fully_scanned_round) -+ scanned_virtual_pages++; -+ -+ if (vma_fully_scanned(slot)) -+ slot->fully_scanned_round = fully_scanned_round; -+} -+ -+static inline unsigned long rung_get_pages(struct scan_rung *rung) -+{ -+ struct slot_tree_node *node; -+ -+ if (!rung->vma_root.rnode) -+ return 0; -+ -+ node = container_of(rung->vma_root.rnode, struct slot_tree_node, snode); -+ -+ return node->size; -+} -+ -+#define RUNG_SAMPLED_MIN 3 -+ -+static inline -+void uksm_calc_rung_step(struct scan_rung *rung, -+ unsigned long page_time, unsigned long ratio) -+{ -+ unsigned long sampled, pages; -+ -+ /* will be fully scanned ? */ -+ if (!rung->cover_msecs) { -+ rung->step = 1; -+ return; -+ } -+ -+ sampled = rung->cover_msecs * (NSEC_PER_MSEC / TIME_RATIO_SCALE) -+ * ratio / page_time; -+ -+ /* -+ * Before we finsish a scan round and expensive per-round jobs, -+ * we need to have a chance to estimate the per page time. So -+ * the sampled number can not be too small. -+ */ -+ if (sampled < RUNG_SAMPLED_MIN) -+ sampled = RUNG_SAMPLED_MIN; -+ -+ pages = rung_get_pages(rung); -+ if (likely(pages > sampled)) -+ rung->step = pages / sampled; -+ else -+ rung->step = 1; -+} -+ -+static inline int step_need_recalc(struct scan_rung *rung) -+{ -+ unsigned long pages, stepmax; -+ -+ pages = rung_get_pages(rung); -+ stepmax = pages / RUNG_SAMPLED_MIN; -+ -+ return pages && (rung->step > pages || -+ (stepmax && rung->step > stepmax)); -+} -+ -+static inline -+void reset_current_scan(struct scan_rung *rung, int finished, int step_recalc) -+{ -+ struct vma_slot *slot; -+ -+ if (finished) -+ rung->flags |= UKSM_RUNG_ROUND_FINISHED; -+ -+ if (step_recalc || step_need_recalc(rung)) { -+ uksm_calc_rung_step(rung, uksm_ema_page_time, rung->cpu_ratio); -+ BUG_ON(step_need_recalc(rung)); -+ } -+ -+ slot_iter_index = prandom_u32() % rung->step; -+ BUG_ON(!rung->vma_root.rnode); -+ slot = sradix_tree_next(&rung->vma_root, NULL, 0, slot_iter); -+ BUG_ON(!slot); -+ -+ rung->current_scan = slot; -+ rung->current_offset = slot_iter_index; -+} -+ -+static inline struct sradix_tree_root *slot_get_root(struct vma_slot *slot) -+{ -+ return &slot->rung->vma_root; -+} -+ -+/* -+ * return if resetted. -+ */ -+static int advance_current_scan(struct scan_rung *rung) -+{ -+ unsigned short n; -+ struct vma_slot *slot, *next = NULL; -+ -+ BUG_ON(!rung->vma_root.num); -+ -+ slot = rung->current_scan; -+ n = (slot->pages - rung->current_offset) % rung->step; -+ slot_iter_index = rung->step - n; -+ next = sradix_tree_next(&rung->vma_root, slot->snode, -+ slot->sindex, slot_iter); -+ -+ if (next) { -+ rung->current_offset = slot_iter_index; -+ rung->current_scan = next; -+ return 0; -+ } else { -+ reset_current_scan(rung, 1, 0); -+ return 1; -+ } -+} -+ -+static inline void rung_rm_slot(struct vma_slot *slot) -+{ -+ struct scan_rung *rung = slot->rung; -+ struct sradix_tree_root *root; -+ -+ if (rung->current_scan == slot) -+ advance_current_scan(rung); -+ -+ root = slot_get_root(slot); -+ sradix_tree_delete_from_leaf(root, slot->snode, slot->sindex); -+ slot->snode = NULL; -+ if (step_need_recalc(rung)) { -+ uksm_calc_rung_step(rung, uksm_ema_page_time, rung->cpu_ratio); -+ BUG_ON(step_need_recalc(rung)); -+ } -+ -+ /* In case advance_current_scan loop back to this slot again */ -+ if (rung->vma_root.num && rung->current_scan == slot) -+ reset_current_scan(slot->rung, 1, 0); -+} -+ -+static inline void rung_add_new_slots(struct scan_rung *rung, -+ struct vma_slot **slots, unsigned long num) -+{ -+ int err; -+ struct vma_slot *slot; -+ unsigned long i; -+ struct sradix_tree_root *root = &rung->vma_root; -+ -+ err = sradix_tree_enter(root, (void **)slots, num); -+ BUG_ON(err); -+ -+ for (i = 0; i < num; i++) { -+ slot = slots[i]; -+ slot->rung = rung; -+ BUG_ON(vma_fully_scanned(slot)); -+ } -+ -+ if (rung->vma_root.num == num) -+ reset_current_scan(rung, 0, 1); -+} -+ -+static inline int rung_add_one_slot(struct scan_rung *rung, -+ struct vma_slot *slot) -+{ -+ int err; -+ -+ err = sradix_tree_enter(&rung->vma_root, (void **)&slot, 1); -+ if (err) -+ return err; -+ -+ slot->rung = rung; -+ if (rung->vma_root.num == 1) -+ reset_current_scan(rung, 0, 1); -+ -+ return 0; -+} -+ -+/* -+ * Return true if the slot is deleted from its rung. -+ */ -+static inline int vma_rung_enter(struct vma_slot *slot, struct scan_rung *rung) -+{ -+ struct scan_rung *old_rung = slot->rung; -+ int err; -+ -+ if (old_rung == rung) -+ return 0; -+ -+ rung_rm_slot(slot); -+ err = rung_add_one_slot(rung, slot); -+ if (err) { -+ err = rung_add_one_slot(old_rung, slot); -+ WARN_ON(err); /* OOPS, badly OOM, we lost this slot */ -+ } -+ -+ return 1; -+} -+ -+static inline int vma_rung_up(struct vma_slot *slot) -+{ -+ struct scan_rung *rung; -+ -+ rung = slot->rung; -+ if (slot->rung != &uksm_scan_ladder[SCAN_LADDER_SIZE-1]) -+ rung++; -+ -+ return vma_rung_enter(slot, rung); -+} -+ -+static inline int vma_rung_down(struct vma_slot *slot) -+{ -+ struct scan_rung *rung; -+ -+ rung = slot->rung; -+ if (slot->rung != &uksm_scan_ladder[0]) -+ rung--; -+ -+ return vma_rung_enter(slot, rung); -+} -+ -+/** -+ * cal_dedup_ratio() - Calculate the deduplication ratio for this slot. -+ */ -+static unsigned long cal_dedup_ratio(struct vma_slot *slot) -+{ -+ unsigned long ret; -+ -+ BUG_ON(slot->pages_scanned == slot->last_scanned); -+ -+ ret = slot->pages_merged; -+ -+ /* Thrashing area filtering */ -+ if (ret && uksm_thrash_threshold) { -+ if (slot->pages_cowed * 100 / slot->pages_merged -+ > uksm_thrash_threshold) { -+ ret = 0; -+ } else { -+ ret = slot->pages_merged - slot->pages_cowed; -+ } -+ } -+ -+ return ret; -+} -+ -+/** -+ * cal_dedup_ratio() - Calculate the deduplication ratio for this slot. -+ */ -+static unsigned long cal_dedup_ratio_old(struct vma_slot *slot) -+{ -+ unsigned long ret; -+ unsigned long pages_scanned; -+ -+ pages_scanned = slot->pages_scanned; -+ if (!pages_scanned) { -+ if (uksm_thrash_threshold) -+ return 0; -+ else -+ pages_scanned = slot->pages_scanned; -+ } -+ -+ ret = slot->pages_bemerged * 100 / pages_scanned; -+ -+ /* Thrashing area filtering */ -+ if (ret && uksm_thrash_threshold) { -+ if (slot->pages_cowed * 100 / slot->pages_bemerged -+ > uksm_thrash_threshold) { -+ ret = 0; -+ } else { -+ ret = slot->pages_bemerged - slot->pages_cowed; -+ } -+ } -+ -+ return ret; -+} -+ -+/** -+ * stable_node_reinsert() - When the hash_strength has been adjusted, the -+ * stable tree need to be restructured, this is the function re-inserting the -+ * stable node. -+ */ -+static inline void stable_node_reinsert(struct stable_node *new_node, -+ struct page *page, -+ struct rb_root *root_treep, -+ struct list_head *tree_node_listp, -+ u32 hash) -+{ -+ struct rb_node **new = &root_treep->rb_node; -+ struct rb_node *parent = NULL; -+ struct stable_node *stable_node; -+ struct tree_node *tree_node; -+ struct page *tree_page; -+ int cmp; -+ -+ while (*new) { -+ int cmp; -+ -+ tree_node = rb_entry(*new, struct tree_node, node); -+ -+ cmp = hash_cmp(hash, tree_node->hash); -+ -+ if (cmp < 0) { -+ parent = *new; -+ new = &parent->rb_left; -+ } else if (cmp > 0) { -+ parent = *new; -+ new = &parent->rb_right; -+ } else -+ break; -+ } -+ -+ if (*new) { -+ /* find a stable tree node with same first level hash value */ -+ stable_node_hash_max(new_node, page, hash); -+ if (tree_node->count == 1) { -+ stable_node = rb_entry(tree_node->sub_root.rb_node, -+ struct stable_node, node); -+ tree_page = get_uksm_page(stable_node, 1, 0); -+ if (tree_page) { -+ stable_node_hash_max(stable_node, -+ tree_page, hash); -+ put_page(tree_page); -+ -+ /* prepare for stable node insertion */ -+ -+ cmp = hash_cmp(new_node->hash_max, -+ stable_node->hash_max); -+ parent = &stable_node->node; -+ if (cmp < 0) -+ new = &parent->rb_left; -+ else if (cmp > 0) -+ new = &parent->rb_right; -+ else -+ goto failed; -+ -+ goto add_node; -+ } else { -+ /* the only stable_node deleted, the tree node -+ * was not deleted. -+ */ -+ goto tree_node_reuse; -+ } -+ } -+ -+ /* well, search the collision subtree */ -+ new = &tree_node->sub_root.rb_node; -+ parent = NULL; -+ BUG_ON(!*new); -+ while (*new) { -+ int cmp; -+ -+ stable_node = rb_entry(*new, struct stable_node, node); -+ -+ cmp = hash_cmp(new_node->hash_max, -+ stable_node->hash_max); -+ -+ if (cmp < 0) { -+ parent = *new; -+ new = &parent->rb_left; -+ } else if (cmp > 0) { -+ parent = *new; -+ new = &parent->rb_right; -+ } else { -+ /* oh, no, still a collision */ -+ goto failed; -+ } -+ } -+ -+ goto add_node; -+ } -+ -+ /* no tree node found */ -+ tree_node = alloc_tree_node(tree_node_listp); -+ if (!tree_node) { -+ printk(KERN_ERR "UKSM: memory allocation error!\n"); -+ goto failed; -+ } else { -+ tree_node->hash = hash; -+ rb_link_node(&tree_node->node, parent, new); -+ rb_insert_color(&tree_node->node, root_treep); -+ -+tree_node_reuse: -+ /* prepare for stable node insertion */ -+ parent = NULL; -+ new = &tree_node->sub_root.rb_node; -+ } -+ -+add_node: -+ rb_link_node(&new_node->node, parent, new); -+ rb_insert_color(&new_node->node, &tree_node->sub_root); -+ new_node->tree_node = tree_node; -+ tree_node->count++; -+ return; -+ -+failed: -+ /* This can only happen when two nodes have collided -+ * in two levels. -+ */ -+ new_node->tree_node = NULL; -+ return; -+} -+ -+static inline void free_all_tree_nodes(struct list_head *list) -+{ -+ struct tree_node *node, *tmp; -+ -+ list_for_each_entry_safe(node, tmp, list, all_list) { -+ free_tree_node(node); -+ } -+} -+ -+/** -+ * stable_tree_delta_hash() - Delta hash the stable tree from previous hash -+ * strength to the current hash_strength. It re-structures the hole tree. -+ */ -+static inline void stable_tree_delta_hash(u32 prev_hash_strength) -+{ -+ struct stable_node *node, *tmp; -+ struct rb_root *root_new_treep; -+ struct list_head *new_tree_node_listp; -+ -+ stable_tree_index = (stable_tree_index + 1) % 2; -+ root_new_treep = &root_stable_tree[stable_tree_index]; -+ new_tree_node_listp = &stable_tree_node_list[stable_tree_index]; -+ *root_new_treep = RB_ROOT; -+ BUG_ON(!list_empty(new_tree_node_listp)); -+ -+ /* -+ * we need to be safe, the node could be removed by get_uksm_page() -+ */ -+ list_for_each_entry_safe(node, tmp, &stable_node_list, all_list) { -+ void *addr; -+ struct page *node_page; -+ u32 hash; -+ -+ /* -+ * We are completely re-structuring the stable nodes to a new -+ * stable tree. We don't want to touch the old tree unlinks and -+ * old tree_nodes. The old tree_nodes will be freed at once. -+ */ -+ node_page = get_uksm_page(node, 0, 0); -+ if (!node_page) -+ continue; -+ -+ if (node->tree_node) { -+ hash = node->tree_node->hash; -+ -+ addr = kmap_atomic(node_page); -+ -+ hash = delta_hash(addr, prev_hash_strength, -+ hash_strength, hash); -+ kunmap_atomic(addr); -+ } else { -+ /* -+ *it was not inserted to rbtree due to collision in last -+ *round scan. -+ */ -+ hash = page_hash(node_page, hash_strength, 0); -+ } -+ -+ stable_node_reinsert(node, node_page, root_new_treep, -+ new_tree_node_listp, hash); -+ put_page(node_page); -+ } -+ -+ root_stable_treep = root_new_treep; -+ free_all_tree_nodes(stable_tree_node_listp); -+ BUG_ON(!list_empty(stable_tree_node_listp)); -+ stable_tree_node_listp = new_tree_node_listp; -+} -+ -+static inline void inc_hash_strength(unsigned long delta) -+{ -+ hash_strength += 1 << delta; -+ if (hash_strength > HASH_STRENGTH_MAX) -+ hash_strength = HASH_STRENGTH_MAX; -+} -+ -+static inline void dec_hash_strength(unsigned long delta) -+{ -+ unsigned long change = 1 << delta; -+ -+ if (hash_strength <= change + 1) -+ hash_strength = 1; -+ else -+ hash_strength -= change; -+} -+ -+static inline void inc_hash_strength_delta(void) -+{ -+ hash_strength_delta++; -+ if (hash_strength_delta > HASH_STRENGTH_DELTA_MAX) -+ hash_strength_delta = HASH_STRENGTH_DELTA_MAX; -+} -+ -+/* -+static inline unsigned long get_current_neg_ratio(void) -+{ -+ if (!rshash_pos || rshash_neg > rshash_pos) -+ return 100; -+ -+ return div64_u64(100 * rshash_neg , rshash_pos); -+} -+*/ -+ -+static inline unsigned long get_current_neg_ratio(void) -+{ -+ u64 pos = benefit.pos; -+ u64 neg = benefit.neg; -+ -+ if (!neg) -+ return 0; -+ -+ if (!pos || neg > pos) -+ return 100; -+ -+ if (neg > div64_u64(U64_MAX, 100)) -+ pos = div64_u64(pos, 100); -+ else -+ neg *= 100; -+ -+ return div64_u64(neg, pos); -+} -+ -+static inline unsigned long get_current_benefit(void) -+{ -+ u64 pos = benefit.pos; -+ u64 neg = benefit.neg; -+ u64 scanned = benefit.scanned; -+ -+ if (neg > pos) -+ return 0; -+ -+ return div64_u64((pos - neg), scanned); -+} -+ -+static inline int judge_rshash_direction(void) -+{ -+ u64 current_neg_ratio, stable_benefit; -+ u64 current_benefit, delta = 0; -+ int ret = STILL; -+ -+ /* Try to probe a value after the boot, and in case the system -+ are still for a long time. */ -+ if ((fully_scanned_round & 0xFFULL) == 10) { -+ ret = OBSCURE; -+ goto out; -+ } -+ -+ current_neg_ratio = get_current_neg_ratio(); -+ -+ if (current_neg_ratio == 0) { -+ rshash_neg_cont_zero++; -+ if (rshash_neg_cont_zero > 2) -+ return GO_DOWN; -+ else -+ return STILL; -+ } -+ rshash_neg_cont_zero = 0; -+ -+ if (current_neg_ratio > 90) { -+ ret = GO_UP; -+ goto out; -+ } -+ -+ current_benefit = get_current_benefit(); -+ stable_benefit = rshash_state.stable_benefit; -+ -+ if (!stable_benefit) { -+ ret = OBSCURE; -+ goto out; -+ } -+ -+ if (current_benefit > stable_benefit) -+ delta = current_benefit - stable_benefit; -+ else if (current_benefit < stable_benefit) -+ delta = stable_benefit - current_benefit; -+ -+ delta = div64_u64(100 * delta , stable_benefit); -+ -+ if (delta > 50) { -+ rshash_cont_obscure++; -+ if (rshash_cont_obscure > 2) -+ return OBSCURE; -+ else -+ return STILL; -+ } -+ -+out: -+ rshash_cont_obscure = 0; -+ return ret; -+} -+ -+/** -+ * rshash_adjust() - The main function to control the random sampling state -+ * machine for hash strength adapting. -+ * -+ * return true if hash_strength has changed. -+ */ -+static inline int rshash_adjust(void) -+{ -+ unsigned long prev_hash_strength = hash_strength; -+ -+ if (!encode_benefit()) -+ return 0; -+ -+ switch (rshash_state.state) { -+ case RSHASH_STILL: -+ switch (judge_rshash_direction()) { -+ case GO_UP: -+ if (rshash_state.pre_direct == GO_DOWN) -+ hash_strength_delta = 0; -+ -+ inc_hash_strength(hash_strength_delta); -+ inc_hash_strength_delta(); -+ rshash_state.stable_benefit = get_current_benefit(); -+ rshash_state.pre_direct = GO_UP; -+ break; -+ -+ case GO_DOWN: -+ if (rshash_state.pre_direct == GO_UP) -+ hash_strength_delta = 0; -+ -+ dec_hash_strength(hash_strength_delta); -+ inc_hash_strength_delta(); -+ rshash_state.stable_benefit = get_current_benefit(); -+ rshash_state.pre_direct = GO_DOWN; -+ break; -+ -+ case OBSCURE: -+ rshash_state.stable_point = hash_strength; -+ rshash_state.turn_point_down = hash_strength; -+ rshash_state.turn_point_up = hash_strength; -+ rshash_state.turn_benefit_down = get_current_benefit(); -+ rshash_state.turn_benefit_up = get_current_benefit(); -+ rshash_state.lookup_window_index = 0; -+ rshash_state.state = RSHASH_TRYDOWN; -+ dec_hash_strength(hash_strength_delta); -+ inc_hash_strength_delta(); -+ break; -+ -+ case STILL: -+ break; -+ default: -+ BUG(); -+ } -+ break; -+ -+ case RSHASH_TRYDOWN: -+ if (rshash_state.lookup_window_index++ % 5 == 0) -+ rshash_state.below_count = 0; -+ -+ if (get_current_benefit() < rshash_state.stable_benefit) -+ rshash_state.below_count++; -+ else if (get_current_benefit() > -+ rshash_state.turn_benefit_down) { -+ rshash_state.turn_point_down = hash_strength; -+ rshash_state.turn_benefit_down = get_current_benefit(); -+ } -+ -+ if (rshash_state.below_count >= 3 || -+ judge_rshash_direction() == GO_UP || -+ hash_strength == 1) { -+ hash_strength = rshash_state.stable_point; -+ hash_strength_delta = 0; -+ inc_hash_strength(hash_strength_delta); -+ inc_hash_strength_delta(); -+ rshash_state.lookup_window_index = 0; -+ rshash_state.state = RSHASH_TRYUP; -+ hash_strength_delta = 0; -+ } else { -+ dec_hash_strength(hash_strength_delta); -+ inc_hash_strength_delta(); -+ } -+ break; -+ -+ case RSHASH_TRYUP: -+ if (rshash_state.lookup_window_index++ % 5 == 0) -+ rshash_state.below_count = 0; -+ -+ if (get_current_benefit() < rshash_state.turn_benefit_down) -+ rshash_state.below_count++; -+ else if (get_current_benefit() > rshash_state.turn_benefit_up) { -+ rshash_state.turn_point_up = hash_strength; -+ rshash_state.turn_benefit_up = get_current_benefit(); -+ } -+ -+ if (rshash_state.below_count >= 3 || -+ judge_rshash_direction() == GO_DOWN || -+ hash_strength == HASH_STRENGTH_MAX) { -+ hash_strength = rshash_state.turn_benefit_up > -+ rshash_state.turn_benefit_down ? -+ rshash_state.turn_point_up : -+ rshash_state.turn_point_down; -+ -+ rshash_state.state = RSHASH_PRE_STILL; -+ } else { -+ inc_hash_strength(hash_strength_delta); -+ inc_hash_strength_delta(); -+ } -+ -+ break; -+ -+ case RSHASH_NEW: -+ case RSHASH_PRE_STILL: -+ rshash_state.stable_benefit = get_current_benefit(); -+ rshash_state.state = RSHASH_STILL; -+ hash_strength_delta = 0; -+ break; -+ default: -+ BUG(); -+ } -+ -+ /* rshash_neg = rshash_pos = 0; */ -+ reset_benefit(); -+ -+ if (prev_hash_strength != hash_strength) -+ stable_tree_delta_hash(prev_hash_strength); -+ -+ return prev_hash_strength != hash_strength; -+} -+ -+/** -+ * round_update_ladder() - The main function to do update of all the -+ * adjustments whenever a scan round is finished. -+ */ -+static noinline void round_update_ladder(void) -+{ -+ int i; -+ unsigned long dedup; -+ struct vma_slot *slot, *tmp_slot; -+ -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ uksm_scan_ladder[i].flags &= ~UKSM_RUNG_ROUND_FINISHED; -+ } -+ -+ list_for_each_entry_safe(slot, tmp_slot, &vma_slot_dedup, dedup_list) { -+ -+ /* slot may be rung_rm_slot() when mm exits */ -+ if (slot->snode) { -+ dedup = cal_dedup_ratio_old(slot); -+ if (dedup && dedup >= uksm_abundant_threshold) -+ vma_rung_up(slot); -+ } -+ -+ slot->pages_bemerged = 0; -+ slot->pages_cowed = 0; -+ -+ list_del_init(&slot->dedup_list); -+ } -+} -+ -+static void uksm_del_vma_slot(struct vma_slot *slot) -+{ -+ int i, j; -+ struct rmap_list_entry *entry; -+ -+ if (slot->snode) { -+ /* -+ * In case it just failed when entering the rung, it's not -+ * necessary. -+ */ -+ rung_rm_slot(slot); -+ } -+ -+ if (!list_empty(&slot->dedup_list)) -+ list_del(&slot->dedup_list); -+ -+ if (!slot->rmap_list_pool || !slot->pool_counts) { -+ /* In case it OOMed in uksm_vma_enter() */ -+ goto out; -+ } -+ -+ for (i = 0; i < slot->pool_size; i++) { -+ void *addr; -+ -+ if (!slot->rmap_list_pool[i]) -+ continue; -+ -+ addr = kmap(slot->rmap_list_pool[i]); -+ for (j = 0; j < PAGE_SIZE / sizeof(*entry); j++) { -+ entry = (struct rmap_list_entry *)addr + j; -+ if (is_addr(entry->addr)) -+ continue; -+ if (!entry->item) -+ continue; -+ -+ remove_rmap_item_from_tree(entry->item); -+ free_rmap_item(entry->item); -+ slot->pool_counts[i]--; -+ } -+ BUG_ON(slot->pool_counts[i]); -+ kunmap(slot->rmap_list_pool[i]); -+ __free_page(slot->rmap_list_pool[i]); -+ } -+ kfree(slot->rmap_list_pool); -+ kfree(slot->pool_counts); -+ -+out: -+ slot->rung = NULL; -+ BUG_ON(uksm_pages_total < slot->pages); -+ if (slot->flags & UKSM_SLOT_IN_UKSM) -+ uksm_pages_total -= slot->pages; -+ -+ if (slot->fully_scanned_round == fully_scanned_round) -+ scanned_virtual_pages -= slot->pages; -+ else -+ scanned_virtual_pages -= slot->pages_scanned; -+ free_vma_slot(slot); -+} -+ -+ -+#define SPIN_LOCK_PERIOD 32 -+static struct vma_slot *cleanup_slots[SPIN_LOCK_PERIOD]; -+static inline void cleanup_vma_slots(void) -+{ -+ struct vma_slot *slot; -+ int i; -+ -+ i = 0; -+ spin_lock(&vma_slot_list_lock); -+ while (!list_empty(&vma_slot_del)) { -+ slot = list_entry(vma_slot_del.next, -+ struct vma_slot, slot_list); -+ list_del(&slot->slot_list); -+ cleanup_slots[i++] = slot; -+ if (i == SPIN_LOCK_PERIOD) { -+ spin_unlock(&vma_slot_list_lock); -+ while (--i >= 0) -+ uksm_del_vma_slot(cleanup_slots[i]); -+ i = 0; -+ spin_lock(&vma_slot_list_lock); -+ } -+ } -+ spin_unlock(&vma_slot_list_lock); -+ -+ while (--i >= 0) -+ uksm_del_vma_slot(cleanup_slots[i]); -+} -+ -+/* -+*expotional moving average formula -+*/ -+static inline unsigned long ema(unsigned long curr, unsigned long last_ema) -+{ -+ /* -+ * For a very high burst, even the ema cannot work well, a false very -+ * high per-page time estimation can result in feedback in very high -+ * overhead of context swith and rung update -- this will then lead -+ * to higher per-paper time, this may not converge. -+ * -+ * Instead, we try to approach this value in a binary manner. -+ */ -+ if (curr > last_ema * 10) -+ return last_ema * 2; -+ -+ return (EMA_ALPHA * curr + (100 - EMA_ALPHA) * last_ema) / 100; -+} -+ -+/* -+ * convert cpu ratio in 1/TIME_RATIO_SCALE configured by user to -+ * nanoseconds based on current uksm_sleep_jiffies. -+ */ -+static inline unsigned long cpu_ratio_to_nsec(unsigned int ratio) -+{ -+ return NSEC_PER_USEC * jiffies_to_usecs(uksm_sleep_jiffies) / -+ (TIME_RATIO_SCALE - ratio) * ratio; -+} -+ -+ -+static inline unsigned long rung_real_ratio(int cpu_time_ratio) -+{ -+ unsigned long ret; -+ -+ BUG_ON(!cpu_time_ratio); -+ -+ if (cpu_time_ratio > 0) -+ ret = cpu_time_ratio; -+ else -+ ret = (unsigned long)(-cpu_time_ratio) * -+ uksm_max_cpu_percentage / 100UL; -+ -+ return ret ? ret : 1; -+} -+ -+static noinline void uksm_calc_scan_pages(void) -+{ -+ struct scan_rung *ladder = uksm_scan_ladder; -+ unsigned long sleep_usecs, nsecs; -+ unsigned long ratio; -+ int i; -+ unsigned long per_page; -+ -+ if (uksm_ema_page_time > 100000 || -+ (((unsigned long) uksm_eval_round & (256UL - 1)) == 0UL)) -+ uksm_ema_page_time = UKSM_PAGE_TIME_DEFAULT; -+ -+ per_page = uksm_ema_page_time; -+ BUG_ON(!per_page); -+ -+ /* -+ * For every 8 eval round, we try to probe a uksm_sleep_jiffies value -+ * based on saved user input. -+ */ -+ if (((unsigned long) uksm_eval_round & (8UL - 1)) == 0UL) -+ uksm_sleep_jiffies = uksm_sleep_saved; -+ -+ /* We require a rung scan at least 1 page in a period. */ -+ nsecs = per_page; -+ ratio = rung_real_ratio(ladder[0].cpu_ratio); -+ if (cpu_ratio_to_nsec(ratio) < nsecs) { -+ sleep_usecs = nsecs * (TIME_RATIO_SCALE - ratio) / ratio -+ / NSEC_PER_USEC; -+ uksm_sleep_jiffies = usecs_to_jiffies(sleep_usecs) + 1; -+ } -+ -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ ratio = rung_real_ratio(ladder[i].cpu_ratio); -+ ladder[i].pages_to_scan = cpu_ratio_to_nsec(ratio) / -+ per_page; -+ BUG_ON(!ladder[i].pages_to_scan); -+ uksm_calc_rung_step(&ladder[i], per_page, ratio); -+ } -+} -+ -+/* -+ * From the scan time of this round (ns) to next expected min sleep time -+ * (ms), be careful of the possible overflows. ratio is taken from -+ * rung_real_ratio() -+ */ -+static inline -+unsigned int scan_time_to_sleep(unsigned long long scan_time, unsigned long ratio) -+{ -+ scan_time >>= 20; /* to msec level now */ -+ BUG_ON(scan_time > (ULONG_MAX / TIME_RATIO_SCALE)); -+ -+ return (unsigned int) ((unsigned long) scan_time * -+ (TIME_RATIO_SCALE - ratio) / ratio); -+} -+ -+#define __round_mask(x, y) ((__typeof__(x))((y)-1)) -+#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) -+ -+static inline unsigned long vma_pool_size(struct vma_slot *slot) -+{ -+ return round_up(sizeof(struct rmap_list_entry) * slot->pages, -+ PAGE_SIZE) >> PAGE_SHIFT; -+} -+ -+static void uksm_vma_enter(struct vma_slot **slots, unsigned long num) -+{ -+ struct scan_rung *rung; -+ unsigned long pool_size, i; -+ struct vma_slot *slot; -+ int failed; -+ -+ rung = &uksm_scan_ladder[0]; -+ -+ failed = 0; -+ for (i = 0; i < num; i++) { -+ slot = slots[i]; -+ -+ pool_size = vma_pool_size(slot); -+ slot->rmap_list_pool = kzalloc(sizeof(struct page *) * -+ pool_size, GFP_KERNEL); -+ if (!slot->rmap_list_pool) -+ break; -+ -+ slot->pool_counts = kzalloc(sizeof(unsigned int) * pool_size, -+ GFP_KERNEL); -+ if (!slot->pool_counts) { -+ kfree(slot->rmap_list_pool); -+ break; -+ } -+ -+ slot->pool_size = pool_size; -+ BUG_ON(CAN_OVERFLOW_U64(uksm_pages_total, slot->pages)); -+ slot->flags |= UKSM_SLOT_IN_UKSM; -+ uksm_pages_total += slot->pages; -+ } -+ -+ if (i) -+ rung_add_new_slots(rung, slots, i); -+ -+ return; -+} -+ -+static struct vma_slot *batch_slots[SLOT_TREE_NODE_STORE_SIZE]; -+ -+static void uksm_enter_all_slots(void) -+{ -+ struct vma_slot *slot; -+ unsigned long index; -+ struct list_head empty_vma_list; -+ int i; -+ -+ i = 0; -+ index = 0; -+ INIT_LIST_HEAD(&empty_vma_list); -+ -+ spin_lock(&vma_slot_list_lock); -+ while (!list_empty(&vma_slot_new)) { -+ slot = list_entry(vma_slot_new.next, -+ struct vma_slot, slot_list); -+ -+ if (!slot->vma->anon_vma) { -+ list_move(&slot->slot_list, &empty_vma_list); -+ } else if (vma_can_enter(slot->vma)) { -+ batch_slots[index++] = slot; -+ list_del_init(&slot->slot_list); -+ } else { -+ list_move(&slot->slot_list, &vma_slot_noadd); -+ } -+ -+ if (++i == SPIN_LOCK_PERIOD || -+ (index && !(index % SLOT_TREE_NODE_STORE_SIZE))) { -+ spin_unlock(&vma_slot_list_lock); -+ -+ if (index && !(index % SLOT_TREE_NODE_STORE_SIZE)) { -+ uksm_vma_enter(batch_slots, index); -+ index = 0; -+ } -+ i = 0; -+ cond_resched(); -+ spin_lock(&vma_slot_list_lock); -+ } -+ } -+ -+ list_splice(&empty_vma_list, &vma_slot_new); -+ -+ spin_unlock(&vma_slot_list_lock); -+ -+ if (index) -+ uksm_vma_enter(batch_slots, index); -+ -+} -+ -+static inline int rung_round_finished(struct scan_rung *rung) -+{ -+ return rung->flags & UKSM_RUNG_ROUND_FINISHED; -+} -+ -+static inline void judge_slot(struct vma_slot *slot) -+{ -+ struct scan_rung *rung = slot->rung; -+ unsigned long dedup; -+ int deleted; -+ -+ dedup = cal_dedup_ratio(slot); -+ if (vma_fully_scanned(slot) && uksm_thrash_threshold) -+ deleted = vma_rung_enter(slot, &uksm_scan_ladder[0]); -+ else if (dedup && dedup >= uksm_abundant_threshold) -+ deleted = vma_rung_up(slot); -+ else -+ deleted = vma_rung_down(slot); -+ -+ slot->pages_merged = 0; -+ slot->pages_cowed = 0; -+ -+ if (vma_fully_scanned(slot)) -+ slot->pages_scanned = 0; -+ -+ slot->last_scanned = slot->pages_scanned; -+ -+ /* If its deleted in above, then rung was already advanced. */ -+ if (!deleted) -+ advance_current_scan(rung); -+} -+ -+ -+static inline int hash_round_finished(void) -+{ -+ if (scanned_virtual_pages > (uksm_pages_total >> 2)) { -+ scanned_virtual_pages = 0; -+ if (uksm_pages_scanned) -+ fully_scanned_round++; -+ -+ return 1; -+ } else { -+ return 0; -+ } -+} -+ -+#define UKSM_MMSEM_BATCH 5 -+#define BUSY_RETRY 100 -+ -+/** -+ * uksm_do_scan() - the main worker function. -+ */ -+static noinline void uksm_do_scan(void) -+{ -+ struct vma_slot *slot, *iter; -+ struct mm_struct *busy_mm; -+ unsigned char round_finished, all_rungs_emtpy; -+ int i, err, mmsem_batch; -+ unsigned long pcost; -+ long long delta_exec; -+ unsigned long vpages, max_cpu_ratio; -+ unsigned long long start_time, end_time, scan_time; -+ unsigned int expected_jiffies; -+ -+ might_sleep(); -+ -+ vpages = 0; -+ -+ start_time = task_sched_runtime(current); -+ max_cpu_ratio = 0; -+ mmsem_batch = 0; -+ -+ for (i = 0; i < SCAN_LADDER_SIZE;) { -+ struct scan_rung *rung = &uksm_scan_ladder[i]; -+ unsigned long ratio; -+ int busy_retry; -+ -+ if (!rung->pages_to_scan) { -+ i++; -+ continue; -+ } -+ -+ if (!rung->vma_root.num) { -+ rung->pages_to_scan = 0; -+ i++; -+ continue; -+ } -+ -+ ratio = rung_real_ratio(rung->cpu_ratio); -+ if (ratio > max_cpu_ratio) -+ max_cpu_ratio = ratio; -+ -+ busy_retry = BUSY_RETRY; -+ /* -+ * Do not consider rung_round_finished() here, just used up the -+ * rung->pages_to_scan quota. -+ */ -+ while (rung->pages_to_scan && rung->vma_root.num && -+ likely(!freezing(current))) { -+ int reset = 0; -+ -+ slot = rung->current_scan; -+ -+ BUG_ON(vma_fully_scanned(slot)); -+ -+ if (mmsem_batch) { -+ err = 0; -+ } else { -+ err = try_down_read_slot_mmap_sem(slot); -+ } -+ -+ if (err == -ENOENT) { -+rm_slot: -+ rung_rm_slot(slot); -+ continue; -+ } -+ -+ busy_mm = slot->mm; -+ -+ if (err == -EBUSY) { -+ /* skip other vmas on the same mm */ -+ do { -+ reset = advance_current_scan(rung); -+ iter = rung->current_scan; -+ busy_retry--; -+ if (iter->vma->vm_mm != busy_mm || -+ !busy_retry || reset) -+ break; -+ } while (1); -+ -+ if (iter->vma->vm_mm != busy_mm) { -+ continue; -+ } else { -+ /* scan round finsished */ -+ break; -+ } -+ } -+ -+ BUG_ON(!vma_can_enter(slot->vma)); -+ if (uksm_test_exit(slot->vma->vm_mm)) { -+ mmsem_batch = 0; -+ up_read(&slot->vma->vm_mm->mmap_sem); -+ goto rm_slot; -+ } -+ -+ if (mmsem_batch) -+ mmsem_batch--; -+ else -+ mmsem_batch = UKSM_MMSEM_BATCH; -+ -+ /* Ok, we have take the mmap_sem, ready to scan */ -+ scan_vma_one_page(slot); -+ rung->pages_to_scan--; -+ vpages++; -+ -+ if (rung->current_offset + rung->step > slot->pages - 1 -+ || vma_fully_scanned(slot)) { -+ up_read(&slot->vma->vm_mm->mmap_sem); -+ judge_slot(slot); -+ mmsem_batch = 0; -+ } else { -+ rung->current_offset += rung->step; -+ if (!mmsem_batch) -+ up_read(&slot->vma->vm_mm->mmap_sem); -+ } -+ -+ busy_retry = BUSY_RETRY; -+ cond_resched(); -+ } -+ -+ if (mmsem_batch) { -+ up_read(&slot->vma->vm_mm->mmap_sem); -+ mmsem_batch = 0; -+ } -+ -+ if (freezing(current)) -+ break; -+ -+ cond_resched(); -+ } -+ end_time = task_sched_runtime(current); -+ delta_exec = end_time - start_time; -+ -+ if (freezing(current)) -+ return; -+ -+ cleanup_vma_slots(); -+ uksm_enter_all_slots(); -+ -+ round_finished = 1; -+ all_rungs_emtpy = 1; -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ struct scan_rung *rung = &uksm_scan_ladder[i]; -+ -+ if (rung->vma_root.num) { -+ all_rungs_emtpy = 0; -+ if (!rung_round_finished(rung)) -+ round_finished = 0; -+ } -+ } -+ -+ if (all_rungs_emtpy) -+ round_finished = 0; -+ -+ if (round_finished) { -+ round_update_ladder(); -+ uksm_eval_round++; -+ -+ if (hash_round_finished() && rshash_adjust()) { -+ /* Reset the unstable root iff hash strength changed */ -+ uksm_hash_round++; -+ root_unstable_tree = RB_ROOT; -+ free_all_tree_nodes(&unstable_tree_node_list); -+ } -+ -+ /* -+ * A number of pages can hang around indefinitely on per-cpu -+ * pagevecs, raised page count preventing write_protect_page -+ * from merging them. Though it doesn't really matter much, -+ * it is puzzling to see some stuck in pages_volatile until -+ * other activity jostles them out, and they also prevented -+ * LTP's KSM test from succeeding deterministically; so drain -+ * them here (here rather than on entry to uksm_do_scan(), -+ * so we don't IPI too often when pages_to_scan is set low). -+ */ -+ lru_add_drain_all(); -+ } -+ -+ -+ if (vpages && delta_exec > 0) { -+ pcost = (unsigned long) delta_exec / vpages; -+ if (likely(uksm_ema_page_time)) -+ uksm_ema_page_time = ema(pcost, uksm_ema_page_time); -+ else -+ uksm_ema_page_time = pcost; -+ } -+ -+ uksm_calc_scan_pages(); -+ uksm_sleep_real = uksm_sleep_jiffies; -+ /* in case of radical cpu bursts, apply the upper bound */ -+ end_time = task_sched_runtime(current); -+ if (max_cpu_ratio && end_time > start_time) { -+ scan_time = end_time - start_time; -+ expected_jiffies = msecs_to_jiffies( -+ scan_time_to_sleep(scan_time, max_cpu_ratio)); -+ -+ if (expected_jiffies > uksm_sleep_real) -+ uksm_sleep_real = expected_jiffies; -+ -+ /* We have a 1 second up bound for responsiveness. */ -+ if (jiffies_to_msecs(uksm_sleep_real) > MSEC_PER_SEC) -+ uksm_sleep_real = msecs_to_jiffies(1000); -+ } -+ -+ return; -+} -+ -+static int ksmd_should_run(void) -+{ -+ return uksm_run & UKSM_RUN_MERGE; -+} -+ -+static int uksm_scan_thread(void *nothing) -+{ -+ set_freezable(); -+ set_user_nice(current, 5); -+ -+ while (!kthread_should_stop()) { -+ mutex_lock(&uksm_thread_mutex); -+ if (ksmd_should_run()) { -+ uksm_do_scan(); -+ } -+ mutex_unlock(&uksm_thread_mutex); -+ -+ try_to_freeze(); -+ -+ if (ksmd_should_run()) { -+ schedule_timeout_interruptible(uksm_sleep_real); -+ uksm_sleep_times++; -+ } else { -+ wait_event_freezable(uksm_thread_wait, -+ ksmd_should_run() || kthread_should_stop()); -+ } -+ } -+ return 0; -+} -+ -+int page_referenced_ksm(struct page *page, struct mem_cgroup *memcg, -+ unsigned long *vm_flags) -+{ -+ struct stable_node *stable_node; -+ struct node_vma *node_vma; -+ struct rmap_item *rmap_item; -+ unsigned int mapcount = page_mapcount(page); -+ int referenced = 0; -+ int search_new_forks = 0; -+ unsigned long address; -+ -+ VM_BUG_ON(!PageKsm(page)); -+ VM_BUG_ON(!PageLocked(page)); -+ -+ stable_node = page_stable_node(page); -+ if (!stable_node) -+ return 0; -+ -+ -+again: -+ hlist_for_each_entry(node_vma, &stable_node->hlist, hlist) { -+ hlist_for_each_entry(rmap_item, &node_vma->rmap_hlist, hlist) { -+ struct anon_vma *anon_vma = rmap_item->anon_vma; -+ struct anon_vma_chain *vmac; -+ struct vm_area_struct *vma; -+ -+ anon_vma_lock_read(anon_vma); -+ anon_vma_interval_tree_foreach(vmac, &anon_vma->rb_root, -+ 0, ULONG_MAX) { -+ -+ vma = vmac->vma; -+ address = get_rmap_addr(rmap_item); -+ -+ if (address < vma->vm_start || -+ address >= vma->vm_end) -+ continue; -+ /* -+ * Initially we examine only the vma which -+ * covers this rmap_item; but later, if there -+ * is still work to do, we examine covering -+ * vmas in other mms: in case they were forked -+ * from the original since ksmd passed. -+ */ -+ if ((rmap_item->slot->vma == vma) == -+ search_new_forks) -+ continue; -+ -+ if (memcg && -+ !mm_match_cgroup(vma->vm_mm, memcg)) -+ continue; -+ -+ referenced += -+ page_referenced_one(page, vma, -+ address, &mapcount, vm_flags); -+ if (!search_new_forks || !mapcount) -+ break; -+ } -+ -+ anon_vma_unlock_read(anon_vma); -+ if (!mapcount) -+ goto out; -+ } -+ } -+ if (!search_new_forks++) -+ goto again; -+out: -+ return referenced; -+} -+ -+int try_to_unmap_ksm(struct page *page, enum ttu_flags flags) -+{ -+ struct stable_node *stable_node; -+ struct node_vma *node_vma; -+ struct rmap_item *rmap_item; -+ int ret = SWAP_AGAIN; -+ int search_new_forks = 0; -+ unsigned long address; -+ -+ VM_BUG_ON(!PageKsm(page)); -+ VM_BUG_ON(!PageLocked(page)); -+ -+ stable_node = page_stable_node(page); -+ if (!stable_node) -+ return SWAP_FAIL; -+again: -+ hlist_for_each_entry(node_vma, &stable_node->hlist, hlist) { -+ hlist_for_each_entry(rmap_item, &node_vma->rmap_hlist, hlist) { -+ struct anon_vma *anon_vma = rmap_item->anon_vma; -+ struct anon_vma_chain *vmac; -+ struct vm_area_struct *vma; -+ -+ anon_vma_lock_read(anon_vma); -+ anon_vma_interval_tree_foreach(vmac, &anon_vma->rb_root, -+ 0, ULONG_MAX) { -+ vma = vmac->vma; -+ address = get_rmap_addr(rmap_item); -+ -+ if (address < vma->vm_start || -+ address >= vma->vm_end) -+ continue; -+ /* -+ * Initially we examine only the vma which -+ * covers this rmap_item; but later, if there -+ * is still work to do, we examine covering -+ * vmas in other mms: in case they were forked -+ * from the original since ksmd passed. -+ */ -+ if ((rmap_item->slot->vma == vma) == -+ search_new_forks) -+ continue; -+ -+ ret = try_to_unmap_one(page, vma, -+ address, flags); -+ if (ret != SWAP_AGAIN || !page_mapped(page)) { -+ anon_vma_unlock_read(anon_vma); -+ goto out; -+ } -+ } -+ anon_vma_unlock_read(anon_vma); -+ } -+ } -+ if (!search_new_forks++) -+ goto again; -+out: -+ return ret; -+} -+ -+#ifdef CONFIG_MIGRATION -+int rmap_walk_ksm(struct page *page, int (*rmap_one)(struct page *, -+ struct vm_area_struct *, unsigned long, void *), void *arg) -+{ -+ struct stable_node *stable_node; -+ struct node_vma *node_vma; -+ struct rmap_item *rmap_item; -+ int ret = SWAP_AGAIN; -+ int search_new_forks = 0; -+ unsigned long address; -+ -+ VM_BUG_ON(!PageKsm(page)); -+ VM_BUG_ON(!PageLocked(page)); -+ -+ stable_node = page_stable_node(page); -+ if (!stable_node) -+ return ret; -+again: -+ hlist_for_each_entry(node_vma, &stable_node->hlist, hlist) { -+ hlist_for_each_entry(rmap_item, &node_vma->rmap_hlist, hlist) { -+ struct anon_vma *anon_vma = rmap_item->anon_vma; -+ struct anon_vma_chain *vmac; -+ struct vm_area_struct *vma; -+ -+ anon_vma_lock_read(anon_vma); -+ anon_vma_interval_tree_foreach(vmac, &anon_vma->rb_root, -+ 0, ULONG_MAX) { -+ vma = vmac->vma; -+ address = get_rmap_addr(rmap_item); -+ -+ if (address < vma->vm_start || -+ address >= vma->vm_end) -+ continue; -+ -+ if ((rmap_item->slot->vma == vma) == -+ search_new_forks) -+ continue; -+ -+ ret = rmap_one(page, vma, address, arg); -+ if (ret != SWAP_AGAIN) { -+ anon_vma_unlock_read(anon_vma); -+ goto out; -+ } -+ } -+ anon_vma_unlock_read(anon_vma); -+ } -+ } -+ if (!search_new_forks++) -+ goto again; -+out: -+ return ret; -+} -+ -+/* Common ksm interface but may be specific to uksm */ -+void ksm_migrate_page(struct page *newpage, struct page *oldpage) -+{ -+ struct stable_node *stable_node; -+ -+ VM_BUG_ON(!PageLocked(oldpage)); -+ VM_BUG_ON(!PageLocked(newpage)); -+ VM_BUG_ON(newpage->mapping != oldpage->mapping); -+ -+ stable_node = page_stable_node(newpage); -+ if (stable_node) { -+ VM_BUG_ON(stable_node->kpfn != page_to_pfn(oldpage)); -+ stable_node->kpfn = page_to_pfn(newpage); -+ } -+} -+#endif /* CONFIG_MIGRATION */ -+ -+#ifdef CONFIG_MEMORY_HOTREMOVE -+static struct stable_node *uksm_check_stable_tree(unsigned long start_pfn, -+ unsigned long end_pfn) -+{ -+ struct rb_node *node; -+ -+ for (node = rb_first(root_stable_treep); node; node = rb_next(node)) { -+ struct stable_node *stable_node; -+ -+ stable_node = rb_entry(node, struct stable_node, node); -+ if (stable_node->kpfn >= start_pfn && -+ stable_node->kpfn < end_pfn) -+ return stable_node; -+ } -+ return NULL; -+} -+ -+static int uksm_memory_callback(struct notifier_block *self, -+ unsigned long action, void *arg) -+{ -+ struct memory_notify *mn = arg; -+ struct stable_node *stable_node; -+ -+ switch (action) { -+ case MEM_GOING_OFFLINE: -+ /* -+ * Keep it very simple for now: just lock out ksmd and -+ * MADV_UNMERGEABLE while any memory is going offline. -+ * mutex_lock_nested() is necessary because lockdep was alarmed -+ * that here we take uksm_thread_mutex inside notifier chain -+ * mutex, and later take notifier chain mutex inside -+ * uksm_thread_mutex to unlock it. But that's safe because both -+ * are inside mem_hotplug_mutex. -+ */ -+ mutex_lock_nested(&uksm_thread_mutex, SINGLE_DEPTH_NESTING); -+ break; -+ -+ case MEM_OFFLINE: -+ /* -+ * Most of the work is done by page migration; but there might -+ * be a few stable_nodes left over, still pointing to struct -+ * pages which have been offlined: prune those from the tree. -+ */ -+ while ((stable_node = uksm_check_stable_tree(mn->start_pfn, -+ mn->start_pfn + mn->nr_pages)) != NULL) -+ remove_node_from_stable_tree(stable_node, 1, 1); -+ /* fallthrough */ -+ -+ case MEM_CANCEL_OFFLINE: -+ mutex_unlock(&uksm_thread_mutex); -+ break; -+ } -+ return NOTIFY_OK; -+} -+#endif /* CONFIG_MEMORY_HOTREMOVE */ -+ -+#ifdef CONFIG_SYSFS -+/* -+ * This all compiles without CONFIG_SYSFS, but is a waste of space. -+ */ -+ -+#define UKSM_ATTR_RO(_name) \ -+ static struct kobj_attribute _name##_attr = __ATTR_RO(_name) -+#define UKSM_ATTR(_name) \ -+ static struct kobj_attribute _name##_attr = \ -+ __ATTR(_name, 0644, _name##_show, _name##_store) -+ -+static ssize_t max_cpu_percentage_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%u\n", uksm_max_cpu_percentage); -+} -+ -+static ssize_t max_cpu_percentage_store(struct kobject *kobj, -+ struct kobj_attribute *attr, -+ const char *buf, size_t count) -+{ -+ unsigned long max_cpu_percentage; -+ int err; -+ -+ err = strict_strtoul(buf, 10, &max_cpu_percentage); -+ if (err || max_cpu_percentage > 100) -+ return -EINVAL; -+ -+ if (max_cpu_percentage == 100) -+ max_cpu_percentage = 99; -+ else if (max_cpu_percentage < 10) -+ max_cpu_percentage = 10; -+ -+ uksm_max_cpu_percentage = max_cpu_percentage; -+ -+ return count; -+} -+UKSM_ATTR(max_cpu_percentage); -+ -+static ssize_t sleep_millisecs_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%u\n", jiffies_to_msecs(uksm_sleep_jiffies)); -+} -+ -+static ssize_t sleep_millisecs_store(struct kobject *kobj, -+ struct kobj_attribute *attr, -+ const char *buf, size_t count) -+{ -+ unsigned long msecs; -+ int err; -+ -+ err = strict_strtoul(buf, 10, &msecs); -+ if (err || msecs > MSEC_PER_SEC) -+ return -EINVAL; -+ -+ uksm_sleep_jiffies = msecs_to_jiffies(msecs); -+ uksm_sleep_saved = uksm_sleep_jiffies; -+ -+ return count; -+} -+UKSM_ATTR(sleep_millisecs); -+ -+ -+static ssize_t cpu_governor_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ int n = sizeof(uksm_cpu_governor_str) / sizeof(char *); -+ int i; -+ -+ buf[0] = '\0'; -+ for (i = 0; i < n ; i++) { -+ if (uksm_cpu_governor == i) -+ strcat(buf, "["); -+ -+ strcat(buf, uksm_cpu_governor_str[i]); -+ -+ if (uksm_cpu_governor == i) -+ strcat(buf, "]"); -+ -+ strcat(buf, " "); -+ } -+ strcat(buf, "\n"); -+ -+ return strlen(buf); -+} -+ -+static inline void init_performance_values(void) -+{ -+ int i; -+ struct scan_rung *rung; -+ struct uksm_cpu_preset_s *preset = uksm_cpu_preset + uksm_cpu_governor; -+ -+ -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ rung = uksm_scan_ladder + i; -+ rung->cpu_ratio = preset->cpu_ratio[i]; -+ rung->cover_msecs = preset->cover_msecs[i]; -+ } -+ -+ uksm_max_cpu_percentage = preset->max_cpu; -+} -+ -+static ssize_t cpu_governor_store(struct kobject *kobj, -+ struct kobj_attribute *attr, -+ const char *buf, size_t count) -+{ -+ int n = sizeof(uksm_cpu_governor_str) / sizeof(char *); -+ -+ for (n--; n >=0 ; n--) { -+ if (!strncmp(buf, uksm_cpu_governor_str[n], -+ strlen(uksm_cpu_governor_str[n]))) -+ break; -+ } -+ -+ if (n < 0) -+ return -EINVAL; -+ else -+ uksm_cpu_governor = n; -+ -+ init_performance_values(); -+ -+ return count; -+} -+UKSM_ATTR(cpu_governor); -+ -+static ssize_t run_show(struct kobject *kobj, struct kobj_attribute *attr, -+ char *buf) -+{ -+ return sprintf(buf, "%u\n", uksm_run); -+} -+ -+static ssize_t run_store(struct kobject *kobj, struct kobj_attribute *attr, -+ const char *buf, size_t count) -+{ -+ int err; -+ unsigned long flags; -+ -+ err = strict_strtoul(buf, 10, &flags); -+ if (err || flags > UINT_MAX) -+ return -EINVAL; -+ if (flags > UKSM_RUN_MERGE) -+ return -EINVAL; -+ -+ mutex_lock(&uksm_thread_mutex); -+ if (uksm_run != flags) { -+ uksm_run = flags; -+ } -+ mutex_unlock(&uksm_thread_mutex); -+ -+ if (flags & UKSM_RUN_MERGE) -+ wake_up_interruptible(&uksm_thread_wait); -+ -+ return count; -+} -+UKSM_ATTR(run); -+ -+static ssize_t abundant_threshold_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%u\n", uksm_abundant_threshold); -+} -+ -+static ssize_t abundant_threshold_store(struct kobject *kobj, -+ struct kobj_attribute *attr, -+ const char *buf, size_t count) -+{ -+ int err; -+ unsigned long flags; -+ -+ err = strict_strtoul(buf, 10, &flags); -+ if (err || flags > 99) -+ return -EINVAL; -+ -+ uksm_abundant_threshold = flags; -+ -+ return count; -+} -+UKSM_ATTR(abundant_threshold); -+ -+static ssize_t thrash_threshold_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%u\n", uksm_thrash_threshold); -+} -+ -+static ssize_t thrash_threshold_store(struct kobject *kobj, -+ struct kobj_attribute *attr, -+ const char *buf, size_t count) -+{ -+ int err; -+ unsigned long flags; -+ -+ err = strict_strtoul(buf, 10, &flags); -+ if (err || flags > 99) -+ return -EINVAL; -+ -+ uksm_thrash_threshold = flags; -+ -+ return count; -+} -+UKSM_ATTR(thrash_threshold); -+ -+static ssize_t cpu_ratios_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ int i, size; -+ struct scan_rung *rung; -+ char *p = buf; -+ -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ rung = &uksm_scan_ladder[i]; -+ -+ if (rung->cpu_ratio > 0) -+ size = sprintf(p, "%d ", rung->cpu_ratio); -+ else -+ size = sprintf(p, "MAX/%d ", -+ TIME_RATIO_SCALE / -rung->cpu_ratio); -+ -+ p += size; -+ } -+ -+ *p++ = '\n'; -+ *p = '\0'; -+ -+ return p - buf; -+} -+ -+static ssize_t cpu_ratios_store(struct kobject *kobj, -+ struct kobj_attribute *attr, -+ const char *buf, size_t count) -+{ -+ int i, cpuratios[SCAN_LADDER_SIZE], err; -+ unsigned long value; -+ struct scan_rung *rung; -+ char *p, *end = NULL; -+ -+ p = kzalloc(count, GFP_KERNEL); -+ if (!p) -+ return -ENOMEM; -+ -+ memcpy(p, buf, count); -+ -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ if (i != SCAN_LADDER_SIZE -1) { -+ end = strchr(p, ' '); -+ if (!end) -+ return -EINVAL; -+ -+ *end = '\0'; -+ } -+ -+ if (strstr(p, "MAX/")) { -+ p = strchr(p, '/') + 1; -+ err = strict_strtoul(p, 10, &value); -+ if (err || value > TIME_RATIO_SCALE || !value) -+ return -EINVAL; -+ -+ cpuratios[i] = - (int) (TIME_RATIO_SCALE / value); -+ } else { -+ err = strict_strtoul(p, 10, &value); -+ if (err || value > TIME_RATIO_SCALE || !value) -+ return -EINVAL; -+ -+ cpuratios[i] = value; -+ } -+ -+ p = end + 1; -+ } -+ -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ rung = &uksm_scan_ladder[i]; -+ -+ rung->cpu_ratio = cpuratios[i]; -+ } -+ -+ return count; -+} -+UKSM_ATTR(cpu_ratios); -+ -+static ssize_t eval_intervals_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ int i, size; -+ struct scan_rung *rung; -+ char *p = buf; -+ -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ rung = &uksm_scan_ladder[i]; -+ size = sprintf(p, "%u ", rung->cover_msecs); -+ p += size; -+ } -+ -+ *p++ = '\n'; -+ *p = '\0'; -+ -+ return p - buf; -+} -+ -+static ssize_t eval_intervals_store(struct kobject *kobj, -+ struct kobj_attribute *attr, -+ const char *buf, size_t count) -+{ -+ int i, err; -+ unsigned long values[SCAN_LADDER_SIZE]; -+ struct scan_rung *rung; -+ char *p, *end = NULL; -+ -+ p = kzalloc(count, GFP_KERNEL); -+ if (!p) -+ return -ENOMEM; -+ -+ memcpy(p, buf, count); -+ -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ if (i != SCAN_LADDER_SIZE -1) { -+ end = strchr(p, ' '); -+ if (!end) -+ return -EINVAL; -+ -+ *end = '\0'; -+ } -+ -+ err = strict_strtoul(p, 10, &values[i]); -+ if (err) -+ return -EINVAL; -+ -+ p = end + 1; -+ } -+ -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ rung = &uksm_scan_ladder[i]; -+ -+ rung->cover_msecs = values[i]; -+ } -+ -+ return count; -+} -+UKSM_ATTR(eval_intervals); -+ -+static ssize_t ema_per_page_time_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%lu\n", uksm_ema_page_time); -+} -+UKSM_ATTR_RO(ema_per_page_time); -+ -+static ssize_t pages_shared_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%lu\n", uksm_pages_shared); -+} -+UKSM_ATTR_RO(pages_shared); -+ -+static ssize_t pages_sharing_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%lu\n", uksm_pages_sharing); -+} -+UKSM_ATTR_RO(pages_sharing); -+ -+static ssize_t pages_unshared_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%lu\n", uksm_pages_unshared); -+} -+UKSM_ATTR_RO(pages_unshared); -+ -+static ssize_t full_scans_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%llu\n", fully_scanned_round); -+} -+UKSM_ATTR_RO(full_scans); -+ -+static ssize_t pages_scanned_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ unsigned long base = 0; -+ u64 delta, ret; -+ -+ if (pages_scanned_stored) { -+ base = pages_scanned_base; -+ ret = pages_scanned_stored; -+ delta = uksm_pages_scanned >> base; -+ if (CAN_OVERFLOW_U64(ret, delta)) { -+ ret >>= 1; -+ delta >>= 1; -+ base++; -+ ret += delta; -+ } -+ } else { -+ ret = uksm_pages_scanned; -+ } -+ -+ while (ret > ULONG_MAX) { -+ ret >>= 1; -+ base++; -+ } -+ -+ if (base) -+ return sprintf(buf, "%lu * 2^%lu\n", (unsigned long)ret, base); -+ else -+ return sprintf(buf, "%lu\n", (unsigned long)ret); -+} -+UKSM_ATTR_RO(pages_scanned); -+ -+static ssize_t hash_strength_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%lu\n", hash_strength); -+} -+UKSM_ATTR_RO(hash_strength); -+ -+static ssize_t sleep_times_show(struct kobject *kobj, -+ struct kobj_attribute *attr, char *buf) -+{ -+ return sprintf(buf, "%llu\n", uksm_sleep_times); -+} -+UKSM_ATTR_RO(sleep_times); -+ -+ -+static struct attribute *uksm_attrs[] = { -+ &max_cpu_percentage_attr.attr, -+ &sleep_millisecs_attr.attr, -+ &cpu_governor_attr.attr, -+ &run_attr.attr, -+ &ema_per_page_time_attr.attr, -+ &pages_shared_attr.attr, -+ &pages_sharing_attr.attr, -+ &pages_unshared_attr.attr, -+ &full_scans_attr.attr, -+ &pages_scanned_attr.attr, -+ &hash_strength_attr.attr, -+ &sleep_times_attr.attr, -+ &thrash_threshold_attr.attr, -+ &abundant_threshold_attr.attr, -+ &cpu_ratios_attr.attr, -+ &eval_intervals_attr.attr, -+ NULL, -+}; -+ -+static struct attribute_group uksm_attr_group = { -+ .attrs = uksm_attrs, -+ .name = "uksm", -+}; -+#endif /* CONFIG_SYSFS */ -+ -+static inline void init_scan_ladder(void) -+{ -+ int i; -+ struct scan_rung *rung; -+ -+ for (i = 0; i < SCAN_LADDER_SIZE; i++) { -+ rung = uksm_scan_ladder + i; -+ slot_tree_init_root(&rung->vma_root); -+ } -+ -+ init_performance_values(); -+ uksm_calc_scan_pages(); -+} -+ -+static inline int cal_positive_negative_costs(void) -+{ -+ struct page *p1, *p2; -+ unsigned char *addr1, *addr2; -+ unsigned long i, time_start, hash_cost; -+ unsigned long loopnum = 0; -+ -+ /*IMPORTANT: volatile is needed to prevent over-optimization by gcc. */ -+ volatile u32 hash; -+ volatile int ret; -+ -+ p1 = alloc_page(GFP_KERNEL); -+ if (!p1) -+ return -ENOMEM; -+ -+ p2 = alloc_page(GFP_KERNEL); -+ if (!p2) -+ return -ENOMEM; -+ -+ addr1 = kmap_atomic(p1); -+ addr2 = kmap_atomic(p2); -+ memset(addr1, prandom_u32(), PAGE_SIZE); -+ memcpy(addr2, addr1, PAGE_SIZE); -+ -+ /* make sure that the two pages differ in last byte */ -+ addr2[PAGE_SIZE-1] = ~addr2[PAGE_SIZE-1]; -+ kunmap_atomic(addr2); -+ kunmap_atomic(addr1); -+ -+ time_start = jiffies; -+ while (jiffies - time_start < 100) { -+ for (i = 0; i < 100; i++) -+ hash = page_hash(p1, HASH_STRENGTH_FULL, 0); -+ loopnum += 100; -+ } -+ hash_cost = (jiffies - time_start); -+ -+ time_start = jiffies; -+ for (i = 0; i < loopnum; i++) -+ ret = pages_identical(p1, p2); -+ memcmp_cost = HASH_STRENGTH_FULL * (jiffies - time_start); -+ memcmp_cost /= hash_cost; -+ printk(KERN_INFO "UKSM: relative memcmp_cost = %lu " -+ "hash=%u cmp_ret=%d.\n", -+ memcmp_cost, hash, ret); -+ -+ __free_page(p1); -+ __free_page(p2); -+ return 0; -+} -+ -+static int init_zeropage_hash_table(void) -+{ -+ struct page *page; -+ char *addr; -+ int i; -+ -+ page = alloc_page(GFP_KERNEL); -+ if (!page) -+ return -ENOMEM; -+ -+ addr = kmap_atomic(page); -+ memset(addr, 0, PAGE_SIZE); -+ kunmap_atomic(addr); -+ -+ zero_hash_table = kmalloc(HASH_STRENGTH_MAX * sizeof(u32), -+ GFP_KERNEL); -+ if (!zero_hash_table) -+ return -ENOMEM; -+ -+ for (i = 0; i < HASH_STRENGTH_MAX; i++) -+ zero_hash_table[i] = page_hash(page, i, 0); -+ -+ __free_page(page); -+ -+ return 0; -+} -+ -+static inline int init_random_sampling(void) -+{ -+ unsigned long i; -+ random_nums = kmalloc(PAGE_SIZE, GFP_KERNEL); -+ if (!random_nums) -+ return -ENOMEM; -+ -+ for (i = 0; i < HASH_STRENGTH_FULL; i++) -+ random_nums[i] = i; -+ -+ for (i = 0; i < HASH_STRENGTH_FULL; i++) { -+ unsigned long rand_range, swap_index, tmp; -+ -+ rand_range = HASH_STRENGTH_FULL - i; -+ swap_index = i + prandom_u32() % rand_range; -+ tmp = random_nums[i]; -+ random_nums[i] = random_nums[swap_index]; -+ random_nums[swap_index] = tmp; -+ } -+ -+ rshash_state.state = RSHASH_NEW; -+ rshash_state.below_count = 0; -+ rshash_state.lookup_window_index = 0; -+ -+ return cal_positive_negative_costs(); -+} -+ -+static int __init uksm_slab_init(void) -+{ -+ rmap_item_cache = UKSM_KMEM_CACHE(rmap_item, 0); -+ if (!rmap_item_cache) -+ goto out; -+ -+ stable_node_cache = UKSM_KMEM_CACHE(stable_node, 0); -+ if (!stable_node_cache) -+ goto out_free1; -+ -+ node_vma_cache = UKSM_KMEM_CACHE(node_vma, 0); -+ if (!node_vma_cache) -+ goto out_free2; -+ -+ vma_slot_cache = UKSM_KMEM_CACHE(vma_slot, 0); -+ if (!vma_slot_cache) -+ goto out_free3; -+ -+ tree_node_cache = UKSM_KMEM_CACHE(tree_node, 0); -+ if (!tree_node_cache) -+ goto out_free4; -+ -+ return 0; -+ -+out_free4: -+ kmem_cache_destroy(vma_slot_cache); -+out_free3: -+ kmem_cache_destroy(node_vma_cache); -+out_free2: -+ kmem_cache_destroy(stable_node_cache); -+out_free1: -+ kmem_cache_destroy(rmap_item_cache); -+out: -+ return -ENOMEM; -+} -+ -+static void __init uksm_slab_free(void) -+{ -+ kmem_cache_destroy(stable_node_cache); -+ kmem_cache_destroy(rmap_item_cache); -+ kmem_cache_destroy(node_vma_cache); -+ kmem_cache_destroy(vma_slot_cache); -+ kmem_cache_destroy(tree_node_cache); -+} -+ -+/* Common interface to ksm, different to it. */ -+int ksm_madvise(struct vm_area_struct *vma, unsigned long start, -+ unsigned long end, int advice, unsigned long *vm_flags) -+{ -+ int err; -+ -+ switch (advice) { -+ case MADV_MERGEABLE: -+ return 0; /* just ignore the advice */ -+ -+ case MADV_UNMERGEABLE: -+ if (!(*vm_flags & VM_MERGEABLE)) -+ return 0; /* just ignore the advice */ -+ -+ if (vma->anon_vma) { -+ err = unmerge_uksm_pages(vma, start, end); -+ if (err) -+ return err; -+ } -+ -+ uksm_remove_vma(vma); -+ *vm_flags &= ~VM_MERGEABLE; -+ break; -+ } -+ -+ return 0; -+} -+ -+/* Common interface to ksm, actually the same. */ -+struct page *ksm_might_need_to_copy(struct page *page, -+ struct vm_area_struct *vma, unsigned long address) -+{ -+ struct anon_vma *anon_vma = page_anon_vma(page); -+ struct page *new_page; -+ -+ if (PageKsm(page)) { -+ if (page_stable_node(page)) -+ return page; /* no need to copy it */ -+ } else if (!anon_vma) { -+ return page; /* no need to copy it */ -+ } else if (anon_vma->root == vma->anon_vma->root && -+ page->index == linear_page_index(vma, address)) { -+ return page; /* still no need to copy it */ -+ } -+ if (!PageUptodate(page)) -+ return page; /* let do_swap_page report the error */ -+ -+ new_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address); -+ if (new_page) { -+ copy_user_highpage(new_page, page, address, vma); -+ -+ SetPageDirty(new_page); -+ __SetPageUptodate(new_page); -+ __set_page_locked(new_page); -+ } -+ -+ return new_page; -+} -+ -+static int __init uksm_init(void) -+{ -+ struct task_struct *uksm_thread; -+ int err; -+ -+ uksm_sleep_jiffies = msecs_to_jiffies(100); -+ uksm_sleep_saved = uksm_sleep_jiffies; -+ -+ slot_tree_init(); -+ init_scan_ladder(); -+ -+ -+ err = init_random_sampling(); -+ if (err) -+ goto out_free2; -+ -+ err = uksm_slab_init(); -+ if (err) -+ goto out_free1; -+ -+ err = init_zeropage_hash_table(); -+ if (err) -+ goto out_free0; -+ -+ uksm_thread = kthread_run(uksm_scan_thread, NULL, "uksmd"); -+ if (IS_ERR(uksm_thread)) { -+ printk(KERN_ERR "uksm: creating kthread failed\n"); -+ err = PTR_ERR(uksm_thread); -+ goto out_free; -+ } -+ -+#ifdef CONFIG_SYSFS -+ err = sysfs_create_group(mm_kobj, &uksm_attr_group); -+ if (err) { -+ printk(KERN_ERR "uksm: register sysfs failed\n"); -+ kthread_stop(uksm_thread); -+ goto out_free; -+ } -+#else -+ uksm_run = UKSM_RUN_MERGE; /* no way for user to start it */ -+ -+#endif /* CONFIG_SYSFS */ -+ -+#ifdef CONFIG_MEMORY_HOTREMOVE -+ /* -+ * Choose a high priority since the callback takes uksm_thread_mutex: -+ * later callbacks could only be taking locks which nest within that. -+ */ -+ hotplug_memory_notifier(uksm_memory_callback, 100); -+#endif -+ return 0; -+ -+out_free: -+ kfree(zero_hash_table); -+out_free0: -+ uksm_slab_free(); -+out_free1: -+ kfree(random_nums); -+out_free2: -+ kfree(uksm_scan_ladder); -+ return err; -+} -+ -+#ifdef MODULE -+module_init(uksm_init) -+#else -+late_initcall(uksm_init); -+#endif -+ -diff --git a/mm/vmstat.c b/mm/vmstat.c -index f42745e..1796e0c 100644 ---- a/mm/vmstat.c -+++ b/mm/vmstat.c -@@ -739,6 +739,9 @@ const char * const vmstat_text[] = { - #endif - "nr_anon_transparent_hugepages", - "nr_free_cma", -+#ifdef CONFIG_UKSM -+ "nr_uksm_zero_pages", -+#endif - "nr_dirty_threshold", - "nr_dirty_background_threshold", - diff --git a/sys-kernel/kogaion-sources/files/security/0001-x86-x32-Correct-invalid-use-of-user-timespec-in-the-.patch b/sys-kernel/kogaion-sources/files/security/0001-x86-x32-Correct-invalid-use-of-user-timespec-in-the-.patch deleted file mode 100644 index 3f1bccc8..00000000 --- a/sys-kernel/kogaion-sources/files/security/0001-x86-x32-Correct-invalid-use-of-user-timespec-in-the-.patch +++ /dev/null @@ -1,80 +0,0 @@ -From 2def2ef2ae5f3990aabdbe8a755911902707d268 Mon Sep 17 00:00:00 2001 -From: PaX Team -Date: Thu, 30 Jan 2014 16:59:25 -0800 -Subject: [PATCH] x86, x32: Correct invalid use of user timespec in the kernel - -The x32 case for the recvmsg() timout handling is broken: - - asmlinkage long compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg, - unsigned int vlen, unsigned int flags, - struct compat_timespec __user *timeout) - { - int datagrams; - struct timespec ktspec; - - if (flags & MSG_CMSG_COMPAT) - return -EINVAL; - - if (COMPAT_USE_64BIT_TIME) - return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, - flags | MSG_CMSG_COMPAT, - (struct timespec *) timeout); - ... - -The timeout pointer parameter is provided by userland (hence the __user -annotation) but for x32 syscalls it's simply cast to a kernel pointer -and is passed to __sys_recvmmsg which will eventually directly -dereference it for both reading and writing. Other callers to -__sys_recvmmsg properly copy from userland to the kernel first. - -The bug was introduced by commit ee4fa23c4bfc ("compat: Use -COMPAT_USE_64BIT_TIME in net/compat.c") and should affect all kernels -since 3.4 (and perhaps vendor kernels if they backported x32 support -along with this code). - -Note that CONFIG_X86_X32_ABI gets enabled at build time and only if -CONFIG_X86_X32 is enabled and ld can build x32 executables. - -Other uses of COMPAT_USE_64BIT_TIME seem fine. - -This addresses CVE-2014-0038. - -Signed-off-by: PaX Team -Signed-off-by: H. Peter Anvin -Cc: # v3.4+ -Signed-off-by: Linus Torvalds ---- - net/compat.c | 9 ++------- - 1 file changed, 2 insertions(+), 7 deletions(-) - -diff --git a/net/compat.c b/net/compat.c -index dd32e34..f50161f 100644 ---- a/net/compat.c -+++ b/net/compat.c -@@ -780,21 +780,16 @@ asmlinkage long compat_sys_recvmmsg(int fd, struct compat_mmsghdr __user *mmsg, - if (flags & MSG_CMSG_COMPAT) - return -EINVAL; - -- if (COMPAT_USE_64BIT_TIME) -- return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, -- flags | MSG_CMSG_COMPAT, -- (struct timespec *) timeout); -- - if (timeout == NULL) - return __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, - flags | MSG_CMSG_COMPAT, NULL); - -- if (get_compat_timespec(&ktspec, timeout)) -+ if (compat_get_timespec(&ktspec, timeout)) - return -EFAULT; - - datagrams = __sys_recvmmsg(fd, (struct mmsghdr __user *)mmsg, vlen, - flags | MSG_CMSG_COMPAT, &ktspec); -- if (datagrams > 0 && put_compat_timespec(&ktspec, timeout)) -+ if (datagrams > 0 && compat_put_timespec(&ktspec, timeout)) - datagrams = -EFAULT; - - return datagrams; --- -1.8.5.3 - diff --git a/sys-kernel/kogaion-sources/kogaion-sources-3.10.25.ebuild b/sys-kernel/kogaion-sources/kogaion-sources-3.10.25.ebuild deleted file mode 100644 index dedc361b..00000000 --- a/sys-kernel/kogaion-sources/kogaion-sources-3.10.25.ebuild +++ /dev/null @@ -1,55 +0,0 @@ -# Distributed under the terms of the GNU General Public License v2 - -EAPI=5 - -inherit eutils - -SLOT=$PVR -CKV=3.10.25 -KV_FULL=${PN}-${PVR} -EXTRAVERSION=kogaion -KERNEL_ARCHIVE="linux-${PV}.tar.xz" -PATCH_ARCHIVE="linux-${PV}-kogaion.tar.gz" -RESTRICT="binchecks strip mirror" -LICENSE="GPL-2" -KEYWORDS="amd64 x86" - -IUSE="" -DEPEND="" -RDEPEND="" -DESCRIPTION="Kogaion Linux Kernel Sources" -HOMEPAGE="http://www.debian.org" -SRC_URI="https://www.kernel.org/pub/linux/kernel/v3.x/${KERNEL_ARCHIVE}" - -S="$WORKDIR/linux-${CKV}" - -pkg_setup() { - export REAL_ARCH="$ARCH" - unset ARCH ; unset LDFLAGS #will interfere with Makefile if set -} - -src_prepare() { - - for p in $(ls ${FILESDIR}/security); do - epatch -p1 "${FILESDIR}/security/$p" || die - done - - for p in $(ls ${FILESDIR}/desktop) ; do - epatch -p1 "${FILESDIR}/desktop/$p" || die - done - - rm -f .config || die -} - -src_compile() { - einfo "Preparing kernel sources for real-world use" || die - make -s mrproper || die "make mrproper failed" -} - -src_install() { - dodir /usr/src/linux-${PV}-kogaion || die - insinto /usr/src/linux-${PV}-kogaion || die - doins -r "${S}"/* || die - cd ${D}/usr/src/linux-${PV}-kogaion || die - make mrproper || die -} diff --git a/sys-kernel/kogaion-sources/kogaion-sources-3.12.10.ebuild b/sys-kernel/kogaion-sources/kogaion-sources-3.12.10.ebuild deleted file mode 100644 index 8c29647b..00000000 --- a/sys-kernel/kogaion-sources/kogaion-sources-3.12.10.ebuild +++ /dev/null @@ -1,22 +0,0 @@ -# Copyright 2004-2014 Kogaion, Argent and ArgOS Linux -# Distributed under the terms of the GNU General Public License v2 - -EAPI=5 - -K_ROGKERNEL_NAME="kogaion" -K_ROGKERNEL_URI_CONFIG="yes" -K_ROGKERNEL_SELF_TARBALL_NAME="kogaion" -K_ONLY_SOURCES="1" -K_ROGKERNEL_FORCE_SUBLEVEL="0" -K_KERNEL_NEW_VERSIONING="1" - -inherit kogaion-kernel - -KEYWORDS="~amd64 ~arm ~x86" -DESCRIPTION="Official Kogaion Linux Standard kernel sources" -RESTRICT="mirror" -IUSE="sources_standalone" - -DEPEND="${DEPEND} - sources_standalone? ( !=sys-kernel/linux-kogaion-${PVR} ) - !sources_standalone? ( =sys-kernel/linux-kogaion-${PVR} )" diff --git a/sys-kernel/kogaion-sources/kogaion-sources-3.14.20.ebuild b/sys-kernel/kogaion-sources/kogaion-sources-3.14.20.ebuild new file mode 100644 index 00000000..8c29647b --- /dev/null +++ b/sys-kernel/kogaion-sources/kogaion-sources-3.14.20.ebuild @@ -0,0 +1,22 @@ +# Copyright 2004-2014 Kogaion, Argent and ArgOS Linux +# Distributed under the terms of the GNU General Public License v2 + +EAPI=5 + +K_ROGKERNEL_NAME="kogaion" +K_ROGKERNEL_URI_CONFIG="yes" +K_ROGKERNEL_SELF_TARBALL_NAME="kogaion" +K_ONLY_SOURCES="1" +K_ROGKERNEL_FORCE_SUBLEVEL="0" +K_KERNEL_NEW_VERSIONING="1" + +inherit kogaion-kernel + +KEYWORDS="~amd64 ~arm ~x86" +DESCRIPTION="Official Kogaion Linux Standard kernel sources" +RESTRICT="mirror" +IUSE="sources_standalone" + +DEPEND="${DEPEND} + sources_standalone? ( !=sys-kernel/linux-kogaion-${PVR} ) + !sources_standalone? ( =sys-kernel/linux-kogaion-${PVR} )" -- cgit v1.2.3