diff options
author | V3n3RiX <venerix@redcorelinux.org> | 2020-12-19 13:38:08 +0000 |
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committer | V3n3RiX <venerix@redcorelinux.org> | 2020-12-19 13:38:08 +0000 |
commit | 05f78d9ab50a90099057de93015e0b89161081b5 (patch) | |
tree | 586330f17a1222ef2c81f156d0ca345a9209825d /sys-kernel/linux-sources-redcore-lts-legacy/files/4.19-0001-MultiQueue-Skiplist-Scheduler-version-v0.180-linux-hardened.patch | |
parent | be4205ac29a871c8c8d740868d5437fc25adcfbb (diff) |
sys-kernel : drop kernel 4.19
Diffstat (limited to 'sys-kernel/linux-sources-redcore-lts-legacy/files/4.19-0001-MultiQueue-Skiplist-Scheduler-version-v0.180-linux-hardened.patch')
-rw-r--r-- | sys-kernel/linux-sources-redcore-lts-legacy/files/4.19-0001-MultiQueue-Skiplist-Scheduler-version-v0.180-linux-hardened.patch | 10305 |
1 files changed, 0 insertions, 10305 deletions
diff --git a/sys-kernel/linux-sources-redcore-lts-legacy/files/4.19-0001-MultiQueue-Skiplist-Scheduler-version-v0.180-linux-hardened.patch b/sys-kernel/linux-sources-redcore-lts-legacy/files/4.19-0001-MultiQueue-Skiplist-Scheduler-version-v0.180-linux-hardened.patch deleted file mode 100644 index ee298f6a..00000000 --- a/sys-kernel/linux-sources-redcore-lts-legacy/files/4.19-0001-MultiQueue-Skiplist-Scheduler-version-v0.180-linux-hardened.patch +++ /dev/null @@ -1,10305 +0,0 @@ -diff -Nur a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c ---- a/arch/powerpc/platforms/cell/spufs/sched.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/arch/powerpc/platforms/cell/spufs/sched.c 2019-02-09 17:46:11.991297545 +0000 -@@ -65,11 +65,6 @@ - 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. - */ -diff -Nur a/arch/x86/Kconfig b/arch/x86/Kconfig ---- a/arch/x86/Kconfig 2019-02-09 17:20:30.461820549 +0000 -+++ b/arch/x86/Kconfig 2019-02-09 17:51:10.780941815 +0000 -@@ -1003,6 +1003,20 @@ - config SCHED_SMT - def_bool y if SMP - -+config SMT_NICE -+ bool "SMT (Hyperthreading) aware nice priority and policy support" -+ depends on SCHED_MUQSS && SCHED_SMT -+ default y -+ ---help--- -+ Enabling Hyperthreading on Intel CPUs decreases the effectiveness -+ of the use of 'nice' levels and different scheduling policies -+ (e.g. realtime) due to sharing of CPU power between hyperthreads. -+ SMT nice support makes each logical CPU aware of what is running on -+ its hyperthread siblings, maintaining appropriate distribution of -+ CPU according to nice levels and scheduling policies at the expense -+ of slightly increased overhead. -+ If unsure say Y here. -+ - config SCHED_MC - def_bool y - prompt "Multi-core scheduler support" -@@ -1033,6 +1047,80 @@ - - If unsure say Y here. - -+choice -+ prompt "CPU scheduler runqueue sharing" -+ default RQ_MC if SCHED_MUQSS -+ default RQ_NONE -+ -+config RQ_NONE -+ bool "No sharing" -+ help -+ This is the default behaviour where the CPU scheduler has one runqueue -+ per CPU, whether it is a physical or logical CPU (hyperthread). -+ -+ This can still be enabled runtime with the boot parameter -+ rqshare=none -+ -+ If unsure, say N. -+ -+config RQ_SMT -+ bool "SMT (hyperthread) siblings" -+ depends on SCHED_SMT && SCHED_MUQSS -+ -+ help -+ With this option enabled, the CPU scheduler will have one runqueue -+ shared by SMT (hyperthread) siblings. As these logical cores share -+ one physical core, sharing the runqueue resource can lead to decreased -+ overhead, lower latency and higher throughput. -+ -+ This can still be enabled runtime with the boot parameter -+ rqshare=smt -+ -+ If unsure, say N. -+ -+config RQ_MC -+ bool "Multicore siblings" -+ depends on SCHED_MC && SCHED_MUQSS -+ help -+ With this option enabled, the CPU scheduler will have one runqueue -+ shared by multicore siblings in addition to any SMT siblings. -+ As these physical cores share caches, sharing the runqueue resource -+ will lead to lower latency, but its effects on overhead and throughput -+ are less predictable. As a general rule, 6 or fewer cores will likely -+ benefit from this, while larger CPUs will only derive a latency -+ benefit. If your workloads are primarily single threaded, this will -+ possibly worsen throughput. If you are only concerned about latency -+ then enable this regardless of how many cores you have. -+ -+ This can still be enabled runtime with the boot parameter -+ rqshare=mc -+ -+ If unsure, say Y. -+ -+config RQ_SMP -+ bool "Symmetric Multi-Processing" -+ depends on SMP && SCHED_MUQSS -+ help -+ With this option enabled, the CPU scheduler will have one runqueue -+ shared by all physical CPUs unless they are on separate NUMA nodes. -+ As physical CPUs usually do not share resources, sharing the runqueue -+ will normally worsen throughput but improve latency. If you only -+ care about latency enable this. -+ -+ This can still be enabled runtime with the boot parameter -+ rqshare=smp -+ -+ If unsure, say N. -+endchoice -+ -+config SHARERQ -+ int -+ default 0 if RQ_NONE -+ default 1 if RQ_SMT -+ default 2 if RQ_MC -+ default 3 if RQ_SMP -+ -+ - config UP_LATE_INIT - def_bool y - depends on !SMP && X86_LOCAL_APIC -diff -Nur a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt ---- a/Documentation/admin-guide/kernel-parameters.txt 2019-02-09 17:20:30.451820228 +0000 -+++ b/Documentation/admin-guide/kernel-parameters.txt 2019-02-09 17:46:11.981297222 +0000 -@@ -4003,6 +4003,14 @@ - Memory area to be used by remote processor image, - managed by CMA. - -+ rqshare= [X86] Select the MuQSS scheduler runqueue sharing type. -+ Format: <string> -+ smt -- Share SMT (hyperthread) sibling runqueues -+ mc -- Share MC (multicore) sibling runqueues -+ smp -- Share SMP runqueues -+ none -- So not share any runqueues -+ Default value is mc -+ - rw [KNL] Mount root device read-write on boot - - S [KNL] Run init in single mode -diff -Nur a/Documentation/scheduler/sched-BFS.txt b/Documentation/scheduler/sched-BFS.txt ---- a/Documentation/scheduler/sched-BFS.txt 1970-01-01 01:00:00.000000000 +0100 -+++ b/Documentation/scheduler/sched-BFS.txt 2019-02-09 17:46:11.981297222 +0000 -@@ -0,0 +1,351 @@ -+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 cache locality beyond the last running CPU. The sched_domains -+information is used to determine the relative virtual "cache distance" that -+other CPUs have from the last CPU a task was running on. CPUs with shared -+caches, such as SMT siblings, or multicore CPUs with shared caches, are treated -+as cache local. CPUs without shared caches are treated as not cache local, and -+CPUs on different NUMA nodes are treated as very distant. This "relative cache -+distance" is used by modifying the virtual deadline value when doing lookups. -+Effectively, the deadline is unaltered between "cache local" CPUs, doubled for -+"cache distant" CPUs, and quadrupled for "very distant" CPUs. The reasoning -+behind the doubling of deadlines is as follows. 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. Doubling the effective deadline is based on the premise that the -+"cache local" CPUs will tend to work on the same tasks up to double the number -+of cache local CPUs, and once the workload is beyond that amount, it is likely -+that none of the tasks are cache warm anywhere anyway. The quadrupling for NUMA -+is a value I pulled out of my arse. -+ -+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 6 on a -+uniprocessor machine, and automatically set to a progressively higher value on -+multiprocessor machines. The reasoning behind increasing the value on more CPUs -+is that the effective latency is decreased by virtue of there being more CPUs on -+BFS (for reasons explained above), and increasing the value allows for less -+cache contention and more throughput. 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. 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. -+ -+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 <kernel@kolivas.org> Fri Aug 27 2010 -diff -Nur a/Documentation/scheduler/sched-MuQSS.txt b/Documentation/scheduler/sched-MuQSS.txt ---- a/Documentation/scheduler/sched-MuQSS.txt 1970-01-01 01:00:00.000000000 +0100 -+++ b/Documentation/scheduler/sched-MuQSS.txt 2019-02-09 17:46:11.991297545 +0000 -@@ -0,0 +1,373 @@ -+MuQSS - The Multiple Queue Skiplist Scheduler by Con Kolivas. -+ -+MuQSS is a per-cpu runqueue variant of the original BFS scheduler with -+one 8 level skiplist per runqueue, and fine grained locking for much more -+scalability. -+ -+ -+Goals. -+ -+The goal of the Multiple Queue Skiplist Scheduler, referred to as MuQSS from -+here on (pronounced mux) 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 MuQSS 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, while still being -+scalable to many CPUs and processes. -+ -+ -+Design summary. -+ -+MuQSS is best described as per-cpu multiple runqueue, O(log n) insertion, O(1) -+lookup, earliest effective virtual deadline first tickless design, loosely based -+on EEVDF (earliest eligible virtual deadline first) and my previous Staircase -+Deadline scheduler, and evolved from the single runqueue O(n) BFS scheduler. -+Each component shall be described in order to understand the significance of, -+and reasoning for it. -+ -+ -+Design reasoning. -+ -+In BFS, the use of a single runqueue across all CPUs meant that each CPU would -+need to scan the entire runqueue looking for the process with the earliest -+deadline and schedule that next, regardless of which CPU it originally came -+from. This made BFS deterministic with respect to latency and provided -+guaranteed latencies dependent on number of processes and CPUs. The single -+runqueue, however, meant that all CPUs would compete for the single lock -+protecting it, which would lead to increasing lock contention as the number of -+CPUs rose and appeared to limit scalability of common workloads beyond 16 -+logical CPUs. Additionally, the O(n) lookup of the runqueue list obviously -+increased overhead proportionate to the number of queued proecesses and led to -+cache thrashing while iterating over the linked list. -+ -+MuQSS is an evolution of BFS, designed to maintain the same scheduling -+decision mechanism and be virtually deterministic without relying on the -+constrained design of the single runqueue by splitting out the single runqueue -+to be per-CPU and use skiplists instead of linked lists. -+ -+The original reason for going back to a single runqueue design for BFS was 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. -+ -+MuQSS works around the problems inherent in multiple runqueue designs by -+making its skip lists priority ordered and through novel use of lockless -+examination of each other runqueue it can decide if it should take the earliest -+deadline task from another runqueue for latency reasons, or for CPU balancing -+reasons. It still does not have a balancing system, choosing to allow the -+next task scheduling decision and task wakeup CPU choice to allow balancing to -+happen by virtue of its choices. -+ -+As a further evolution of the design, MuQSS normally configures sharing of -+runqueues in a logical fashion for when CPU resources are shared for improved -+latency and throughput. By default it shares runqueues and locks between -+multicore siblings. Optionally it can be configured to run with sharing of -+SMT siblings only, all SMP packages or no sharing at all. Additionally it can -+be selected at boot time. -+ -+ -+Design details. -+ -+Custom skip list implementation: -+ -+To avoid the overhead of building up and tearing down skip list structures, -+the variant used by MuQSS has a number of optimisations making it specific for -+its use case in the scheduler. It uses static arrays of 8 'levels' instead of -+building up and tearing down structures dynamically. This makes each runqueue -+only scale O(log N) up to 64k tasks. However as there is one runqueue per CPU -+it means that it scales O(log N) up to 64k x number of logical CPUs which is -+far beyond the realistic task limits each CPU could handle. By being 8 levels -+it also makes the array exactly one cacheline in size. Additionally, each -+skip list node is bidirectional making insertion and removal amortised O(1), -+being O(k) where k is 1-8. Uniquely, we are only ever interested in the very -+first entry in each list at all times with MuQSS, so there is never a need to -+do a search and thus look up is always O(1). In interactive mode, the queues -+will be searched beyond their first entry if the first task is not suitable -+for affinity or SMT nice reasons. -+ -+Task insertion: -+ -+MuQSS inserts tasks into a per CPU runqueue as an O(log N) insertion into -+a custom skip list as described above (based on the original design by William -+Pugh). Insertion is ordered in such a way that there is never a need to do a -+search by ordering tasks according to static priority primarily, and then -+virtual deadline at the time of insertion. -+ -+Niffies: -+ -+Niffies are a monotonic forward moving timer not unlike the "jiffies" but are -+of nanosecond resolution. Niffies are calculated per-runqueue from the high -+resolution TSC timers, and in order to maintain fairness are synchronised -+between CPUs whenever both runqueues are locked concurrently. -+ -+Virtual deadline: -+ -+The key to achieving low latency, scheduling fairness, and "nice level" -+distribution in MuQSS is entirely in the virtual deadline mechanism. The one -+tunable in MuQSS 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 niffies by this equation: -+ -+ niffies + (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. -+ -+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" (niffies) is -+constantly moving. -+ -+Task lookup: -+ -+As tasks are already pre-ordered according to anticipated scheduling order in -+the skip lists, lookup for the next suitable task per-runqueue is always a -+matter of simply selecting the first task in the 0th level skip list entry. -+In order to maintain optimal latency and fairness across CPUs, MuQSS does a -+novel examination of every other runqueue in cache locality order, choosing the -+best task across all runqueues. This provides near-determinism of how long any -+task across the entire system may wait before receiving CPU time. The other -+runqueues are first examine lockless and then trylocked to minimise the -+potential lock contention if they are likely to have a suitable better task. -+Each other runqueue lock is only held for as long as it takes to examine the -+entry for suitability. In "interactive" mode, the default setting, MuQSS will -+look for the best deadline task across all CPUs, while in !interactive mode, -+it will only select a better deadline task from another CPU if it is more -+heavily laden than the current one. -+ -+Lookup is therefore O(k) where k is number of CPUs. -+ -+ -+Latency. -+ -+Through the use of virtual deadlines to govern the scheduling order of normal -+tasks, queue-to-activation latency per runqueue is guaranteed to be bound by -+the rr_interval tunable which is set to 6ms by default. This means that the -+longest a CPU bound task will wait for more CPU is proportional to the number -+of running tasks and in the common case of 0-2 running tasks per CPU, will be -+under the 7ms threshold for human perception of jitter. Additionally, as newly -+woken tasks will have an early deadline from their previous runtime, the very -+tasks that are usually latency sensitive will have the shortest interval for -+activation, usually preempting any existing CPU bound tasks. -+ -+Tickless expiry: -+ -+A feature of MuQSS is that it is not tied to the resolution of the chosen tick -+rate in Hz, instead depending entirely on the high resolution timers where -+possible for sub-millisecond accuracy on timeouts regarless of the underlying -+tick rate. This allows MuQSS to be run with the low overhead of low Hz rates -+such as 100 by default, benefiting from the improved throughput and lower -+power usage it provides. Another advantage of this approach is that in -+combination with the Full No HZ option, which disables ticks on running task -+CPUs instead of just idle CPUs, the tick can be disabled at all times -+regardless of how many tasks are running instead of being limited to just one -+running task. Note that this option is NOT recommended for regular desktop -+users. -+ -+ -+Scalability and balancing. -+ -+Unlike traditional approaches where balancing is a combination of CPU selection -+at task wakeup and intermittent balancing based on a vast array of rules set -+according to architecture, busyness calculations and special case management, -+MuQSS indirectly balances on the fly at task wakeup and next task selection. -+During initialisation, MuQSS creates a cache coherency ordered list of CPUs for -+each logical CPU and uses this to aid task/CPU selection when CPUs are busy. -+Additionally it selects any idle CPUs, if they are available, at any time over -+busy CPUs according to the following preference: -+ -+ * Same thread, 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. -+ -+Mux is therefore SMT, MC and Numa aware without the need for extra -+intermittent balancing to maintain CPUs busy and make the most of cache -+coherency. -+ -+ -+Features -+ -+As the initial prime target audience for MuQSS 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 3 optional tunables, and 2 extra scheduling policies. The rr_interval, -+interactive, and iso_cpu tunables, and the SCHED_ISO and SCHED_IDLEPRIO -+policies. In addition to this, MuQSS also uses sub-tick accounting. What MuQSS -+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. However since some applications refuse to work without -+cgroups, one can enable them with MuQSS as a stub and the filesystem will be -+created which will allow the applications to work. -+ -+rr_interval: -+ -+ /proc/sys/kernel/rr_interval -+ -+The value is in milliseconds, and the default value is set to 6. 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. 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 MuQSS to other schedulers. Worst case latencies being -+higher than 7ms are far worse than average latencies not being in the -+microsecond range. -+ -+interactive: -+ -+ /proc/sys/kernel/interactive -+ -+The value is a simple boolean of 1 for on and 0 for off and is set to on by -+default. Disabling this will disable the near-determinism of MuQSS when -+selecting the next task by not examining all CPUs for the earliest deadline -+task, or which CPU to wake to, instead prioritising CPU balancing for improved -+throughput. Latency will still be bound by rr_interval, but on a per-CPU basis -+instead of across the whole system. -+ -+Runqueue sharing. -+ -+By default MuQSS chooses to share runqueue resources (specifically the skip -+list and locking) between multicore siblings. It is configurable at build time -+to select between None, SMT, MC and SMP, corresponding to no sharing, sharing -+only between simultaneous mulithreading siblings, multicore siblings, or -+symmetric multiprocessing physical packages. Additionally it can be se at -+bootime with the use of the rqshare parameter. The reason for configurability -+is that some architectures have CPUs with many multicore siblings (>= 16) -+where it may be detrimental to throughput to share runqueues and another -+sharing option may be desirable. Additionally, more sharing than usual can -+improve latency on a system-wide level at the expense of throughput if desired. -+ -+The options are: -+none, smt, mc, smp -+ -+eg: -+ rqshare=mc -+ -+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 CPU available per CPU, configurable as a percentage in -+the following "resource handling" tunable (as opposed to a scheduler tunable): -+ -+iso_cpu: -+ -+ /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 MuQSS 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. -+ -+ -+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. Once a task has -+been scheduled as IDLEPRIO, it cannot be put back to SCHED_NORMAL without -+superuser privileges since it is effectively a lower scheduling policy. 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. Mux uses sub-tick accounting from the TSC clock to determine real CPU -+usage. Thus, the amount of CPU reported as being used by MuQSS 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. When comparing throughput of MuQSS 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". -+ -+Symmetric MultiThreading (SMT) aware nice: -+ -+SMT, a.k.a. hyperthreading, is a very common feature on modern CPUs. While the -+logical CPU count rises by adding thread units to each CPU core, allowing more -+than one task to be run simultaneously on the same core, the disadvantage of it -+is that the CPU power is shared between the tasks, not summating to the power -+of two CPUs. The practical upshot of this is that two tasks running on -+separate threads of the same core run significantly slower than if they had one -+core each to run on. While smart CPU selection allows each task to have a core -+to itself whenever available (as is done on MuQSS), it cannot offset the -+slowdown that occurs when the cores are all loaded and only a thread is left. -+Most of the time this is harmless as the CPU is effectively overloaded at this -+point and the extra thread is of benefit. However when running a niced task in -+the presence of an un-niced task (say nice 19 v nice 0), the nice task gets -+precisely the same amount of CPU power as the unniced one. MuQSS has an -+optional configuration feature known as SMT-NICE which selectively idles the -+secondary niced thread for a period proportional to the nice difference, -+allowing CPU distribution according to nice level to be maintained, at the -+expense of a small amount of extra overhead. If this is configured in on a -+machine without SMT threads, the overhead is minimal. -+ -+ -+Con Kolivas <kernel@kolivas.org> Sat, 29th October 2016 -diff -Nur a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt ---- a/Documentation/sysctl/kernel.txt 2019-02-09 17:20:30.451820228 +0000 -+++ b/Documentation/sysctl/kernel.txt 2019-02-09 17:46:11.991297545 +0000 -@@ -41,6 +41,7 @@ - - hung_task_check_interval_secs - - hung_task_warnings - - hyperv_record_panic_msg -+- iso_cpu - - kexec_load_disabled - - kptr_restrict - - l2cr [ PPC only ] -@@ -76,6 +77,7 @@ - - randomize_va_space - - real-root-dev ==> Documentation/admin-guide/initrd.rst - - reboot-cmd [ SPARC only ] -+- rr_interval - - rtsig-max - - rtsig-nr - - seccomp/ ==> Documentation/userspace-api/seccomp_filter.rst -@@ -98,6 +100,7 @@ - - unknown_nmi_panic - - watchdog - - watchdog_thresh -+- yield_type - - version - - ============================================================== -@@ -436,6 +439,16 @@ - - ============================================================== - -+iso_cpu: (MuQSS 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 -@@ -863,6 +876,20 @@ - - ============================================================== - -+rr_interval: (MuQSS 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 -@@ -1123,3 +1150,13 @@ - tunable to zero will disable lockup detection altogether. - - ============================================================== -+ -+yield_type: (MuQSS CPU scheduler only) -+ -+This determines what type of yield calls to sched_yield will perform. -+ -+ 0: No yield. -+ 1: Yield only to better priority/deadline tasks. (default) -+ 2: Expire timeslice and recalculate deadline. -+ -+============================================================== -diff -Nur a/fs/proc/base.c b/fs/proc/base.c ---- a/fs/proc/base.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/fs/proc/base.c 2019-02-09 17:46:11.991297545 +0000 -@@ -459,7 +459,7 @@ - seq_printf(m, "0 0 0\n"); - else - seq_printf(m, "%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); - -diff -Nur a/include/linux/init_task.h b/include/linux/init_task.h ---- a/include/linux/init_task.h 2019-02-06 16:30:16.000000000 +0000 -+++ b/include/linux/init_task.h 2019-02-09 17:46:11.991297545 +0000 -@@ -46,7 +46,11 @@ - #define INIT_CPU_TIMERS(s) - #endif - -+#ifdef CONFIG_SCHED_MUQSS -+#define INIT_TASK_COMM "MuQSS" -+#else - #define INIT_TASK_COMM "swapper" -+#endif - - /* Attach to the init_task data structure for proper alignment */ - #ifdef CONFIG_ARCH_TASK_STRUCT_ON_STACK -diff -Nur a/include/linux/ioprio.h b/include/linux/ioprio.h ---- a/include/linux/ioprio.h 2019-02-06 16:30:16.000000000 +0000 -+++ b/include/linux/ioprio.h 2019-02-09 17:46:11.991297545 +0000 -@@ -53,6 +53,8 @@ - */ - static inline int task_nice_ioprio(struct task_struct *task) - { -+ if (iso_task(task)) -+ return 0; - return (task_nice(task) + 20) / 5; - } - -diff -Nur a/include/linux/sched/nohz.h b/include/linux/sched/nohz.h ---- a/include/linux/sched/nohz.h 2019-02-06 16:30:16.000000000 +0000 -+++ b/include/linux/sched/nohz.h 2019-02-09 17:46:11.991297545 +0000 -@@ -6,7 +6,7 @@ - * This is the interface between the scheduler and nohz/dynticks: - */ - --#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) -+#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) && !defined(CONFIG_SCHED_MUQSS) - extern void cpu_load_update_nohz_start(void); - extern void cpu_load_update_nohz_stop(void); - #else -@@ -21,7 +21,7 @@ - static inline void nohz_balance_enter_idle(int cpu) { } - #endif - --#ifdef CONFIG_NO_HZ_COMMON -+#if defined(CONFIG_NO_HZ_COMMON) && !defined(CONFIG_SCHED_MUQSS) - void calc_load_nohz_start(void); - void calc_load_nohz_stop(void); - #else -diff -Nur a/include/linux/sched/prio.h b/include/linux/sched/prio.h ---- a/include/linux/sched/prio.h 2019-02-06 16:30:16.000000000 +0000 -+++ b/include/linux/sched/prio.h 2019-02-09 17:46:11.991297545 +0000 -@@ -20,8 +20,20 @@ - */ - - #define MAX_USER_RT_PRIO 100 -+ -+#ifdef CONFIG_SCHED_MUQSS -+/* Note different MAX_RT_PRIO */ -+#define MAX_RT_PRIO (MAX_USER_RT_PRIO + 1) -+ -+#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_MUQSS */ - #define MAX_RT_PRIO MAX_USER_RT_PRIO - -+#endif /* CONFIG_SCHED_MUQSS */ -+ - #define MAX_PRIO (MAX_RT_PRIO + NICE_WIDTH) - #define DEFAULT_PRIO (MAX_RT_PRIO + NICE_WIDTH / 2) - -diff -Nur a/include/linux/sched/rt.h b/include/linux/sched/rt.h ---- a/include/linux/sched/rt.h 2019-02-06 16:30:16.000000000 +0000 -+++ b/include/linux/sched/rt.h 2019-02-09 17:46:11.991297545 +0000 -@@ -24,8 +24,10 @@ - - if (policy == SCHED_FIFO || policy == SCHED_RR) - return true; -+#ifndef CONFIG_SCHED_MUQSS - if (policy == SCHED_DEADLINE) - return true; -+#endif - return false; - } - -diff -Nur a/include/linux/sched/task.h b/include/linux/sched/task.h ---- a/include/linux/sched/task.h 2019-02-06 16:30:16.000000000 +0000 -+++ b/include/linux/sched/task.h 2019-02-09 17:46:11.991297545 +0000 -@@ -80,7 +80,7 @@ - extern void free_task(struct task_struct *tsk); - - /* sched_exec is called by processes performing an exec */ --#ifdef CONFIG_SMP -+#if defined(CONFIG_SMP) && !defined(CONFIG_SCHED_MUQSS) - extern void sched_exec(void); - #else - #define sched_exec() {} -diff -Nur a/include/linux/sched.h b/include/linux/sched.h ---- a/include/linux/sched.h 2019-02-06 16:30:16.000000000 +0000 -+++ b/include/linux/sched.h 2019-02-09 17:46:11.991297545 +0000 -@@ -28,6 +28,9 @@ - #include <linux/mm_types_task.h> - #include <linux/task_io_accounting.h> - #include <linux/rseq.h> -+#ifdef CONFIG_SCHED_MUQSS -+#include <linux/skip_list.h> -+#endif - - /* task_struct member predeclarations (sorted alphabetically): */ - struct audit_context; -@@ -613,9 +616,11 @@ - unsigned int flags; - unsigned int ptrace; - -+#if defined(CONFIG_SMP) || defined(CONFIG_SCHED_MUQSS) -+ int on_cpu; -+#endif - #ifdef CONFIG_SMP - struct llist_node wake_entry; -- int on_cpu; - #ifdef CONFIG_THREAD_INFO_IN_TASK - /* Current CPU: */ - unsigned int cpu; -@@ -640,10 +645,25 @@ - int static_prio; - int normal_prio; - unsigned int rt_priority; -+#ifdef CONFIG_SCHED_MUQSS -+ int time_slice; -+ u64 deadline; -+ skiplist_node node; /* Skip list node */ -+ u64 last_ran; -+ u64 sched_time; /* sched_clock time spent running */ -+#ifdef CONFIG_SMT_NICE -+ int smt_bias; /* Policy/nice level bias across smt siblings */ -+#endif -+#ifdef CONFIG_HOTPLUG_CPU -+ bool zerobound; /* Bound to CPU0 for hotplug */ -+#endif -+ unsigned long rt_timeout; -+#else /* CONFIG_SCHED_MUQSS */ - - const struct sched_class *sched_class; - struct sched_entity se; - struct sched_rt_entity rt; -+#endif - #ifdef CONFIG_CGROUP_SCHED - struct task_group *sched_task_group; - #endif -@@ -798,6 +818,10 @@ - u64 utimescaled; - u64 stimescaled; - #endif -+#ifdef CONFIG_SCHED_MUQSS -+ /* Unbanked cpu time */ -+ unsigned long utime_ns, stime_ns; -+#endif - u64 gtime; - struct prev_cputime prev_cputime; - #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN -@@ -1210,6 +1234,40 @@ - */ - }; - -+#ifdef CONFIG_SCHED_MUQSS -+#define tsk_seruntime(t) ((t)->sched_time) -+#define tsk_rttimeout(t) ((t)->rt_timeout) -+ -+static inline void tsk_cpus_current(struct task_struct *p) -+{ -+} -+ -+void print_scheduler_version(void); -+ -+static inline bool iso_task(struct task_struct *p) -+{ -+ return (p->policy == SCHED_ISO); -+} -+#else /* CFS */ -+#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; -+} -+#endif /* CONFIG_SCHED_MUQSS */ -+ - static inline struct pid *task_pid(struct task_struct *task) - { - return task->thread_pid; -diff -Nur a/include/linux/skip_list.h b/include/linux/skip_list.h ---- a/include/linux/skip_list.h 1970-01-01 01:00:00.000000000 +0100 -+++ b/include/linux/skip_list.h 2019-02-09 17:46:11.991297545 +0000 -@@ -0,0 +1,33 @@ -+#ifndef _LINUX_SKIP_LISTS_H -+#define _LINUX_SKIP_LISTS_H -+typedef u64 keyType; -+typedef void *valueType; -+ -+typedef struct nodeStructure skiplist_node; -+ -+struct nodeStructure { -+ int level; /* Levels in this structure */ -+ keyType key; -+ valueType value; -+ skiplist_node *next[8]; -+ skiplist_node *prev[8]; -+}; -+ -+typedef struct listStructure { -+ int entries; -+ int level; /* Maximum level of the list -+ (1 more than the number of levels in the list) */ -+ skiplist_node *header; /* pointer to header */ -+} skiplist; -+ -+void skiplist_init(skiplist_node *slnode); -+skiplist *new_skiplist(skiplist_node *slnode); -+void free_skiplist(skiplist *l); -+void skiplist_node_init(skiplist_node *node); -+void skiplist_insert(skiplist *l, skiplist_node *node, keyType key, valueType value, unsigned int randseed); -+void skiplist_delete(skiplist *l, skiplist_node *node); -+ -+static inline bool skiplist_node_empty(skiplist_node *node) { -+ return (!node->next[0]); -+} -+#endif /* _LINUX_SKIP_LISTS_H */ -diff -Nur a/include/uapi/linux/sched.h b/include/uapi/linux/sched.h ---- a/include/uapi/linux/sched.h 2019-02-06 16:30:16.000000000 +0000 -+++ b/include/uapi/linux/sched.h 2019-02-09 17:46:11.991297545 +0000 -@@ -37,9 +37,16 @@ - #define SCHED_FIFO 1 - #define SCHED_RR 2 - #define SCHED_BATCH 3 --/* SCHED_ISO: reserved but not implemented yet */ -+/* SCHED_ISO: Implemented on MuQSS only */ - #define SCHED_IDLE 5 -+#ifdef CONFIG_SCHED_MUQSS -+#define SCHED_ISO 4 -+#define SCHED_IDLEPRIO SCHED_IDLE -+#define SCHED_MAX (SCHED_IDLEPRIO) -+#define SCHED_RANGE(policy) ((policy) <= SCHED_MAX) -+#else /* CONFIG_SCHED_MUQSS */ - #define SCHED_DEADLINE 6 -+#endif /* CONFIG_SCHED_MUQSS */ - - /* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */ - #define SCHED_RESET_ON_FORK 0x40000000 -diff -Nur a/init/init_task.c b/init/init_task.c ---- a/init/init_task.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/init/init_task.c 2019-02-09 17:46:11.991297545 +0000 -@@ -67,9 +67,17 @@ - .stack = init_stack, - .usage = ATOMIC_INIT(2), - .flags = PF_KTHREAD, -+#ifdef CONFIG_SCHED_MUQSS -+ .prio = NORMAL_PRIO, -+ .static_prio = MAX_PRIO-20, -+ .normal_prio = NORMAL_PRIO, -+ .deadline = 0, -+ .time_slice = 1000000, -+#else - .prio = MAX_PRIO - 20, - .static_prio = MAX_PRIO - 20, - .normal_prio = MAX_PRIO - 20, -+#endif - .policy = SCHED_NORMAL, - .cpus_allowed = CPU_MASK_ALL, - .nr_cpus_allowed= NR_CPUS, -@@ -78,6 +86,7 @@ - .restart_block = { - .fn = do_no_restart_syscall, - }, -+#ifndef CONFIG_SCHED_MUQSS - .se = { - .group_node = LIST_HEAD_INIT(init_task.se.group_node), - }, -@@ -85,6 +94,7 @@ - .run_list = LIST_HEAD_INIT(init_task.rt.run_list), - .time_slice = RR_TIMESLICE, - }, -+#endif - .tasks = LIST_HEAD_INIT(init_task.tasks), - #ifdef CONFIG_SMP - .pushable_tasks = PLIST_NODE_INIT(init_task.pushable_tasks, MAX_PRIO), -diff -Nur a/init/Kconfig b/init/Kconfig ---- a/init/Kconfig 2019-02-09 17:20:30.481821193 +0000 -+++ b/init/Kconfig 2019-02-09 17:46:11.991297545 +0000 -@@ -45,6 +45,18 @@ - - menu "General setup" - -+config SCHED_MUQSS -+ bool "MuQSS cpu scheduler" -+ select HIGH_RES_TIMERS -+ ---help--- -+ The Multiple Queue Skiplist Scheduler for excellent interactivity and -+ responsiveness on the desktop and highly scalable deterministic -+ low latency on any hardware. -+ -+ Say Y here. -+ default y -+ -+ - config BROKEN - bool - -@@ -653,6 +665,7 @@ - depends on ARCH_SUPPORTS_NUMA_BALANCING - depends on !ARCH_WANT_NUMA_VARIABLE_LOCALITY - depends on SMP && NUMA && MIGRATION -+ depends on !SCHED_MUQSS - help - This option adds support for automatic NUMA aware memory/task placement. - The mechanism is quite primitive and is based on migrating memory when -@@ -760,9 +773,13 @@ - help - This feature lets CPU scheduler recognize task groups and control CPU - bandwidth allocation to such task groups. It uses cgroups to group -- tasks. -+ tasks. In combination with MuQSS this is purely a STUB to create the -+ files associated with the CPU controller cgroup but most of the -+ controls do nothing. This is useful for working in environments and -+ with applications that will only work if this control group is -+ present. - --if CGROUP_SCHED -+if CGROUP_SCHED && !SCHED_MUQSS - config FAIR_GROUP_SCHED - bool "Group scheduling for SCHED_OTHER" - depends on CGROUP_SCHED -@@ -869,6 +886,7 @@ - - config CGROUP_CPUACCT - bool "Simple CPU accounting controller" -+ depends on !SCHED_MUQSS - help - Provides a simple controller for monitoring the - total CPU consumed by the tasks in a cgroup. -@@ -987,6 +1005,7 @@ - - config SCHED_AUTOGROUP - bool "Automatic process group scheduling" -+ depends on !SCHED_MUQSS - select CGROUPS - select CGROUP_SCHED - select FAIR_GROUP_SCHED -diff -Nur a/init/main.c b/init/main.c ---- a/init/main.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/init/main.c 2019-02-09 17:46:11.991297545 +0000 -@@ -1079,6 +1079,8 @@ - - rcu_end_inkernel_boot(); - -+ print_scheduler_version(); -+ - if (ramdisk_execute_command) { - ret = run_init_process(ramdisk_execute_command); - if (!ret) -diff -Nur a/kernel/delayacct.c b/kernel/delayacct.c ---- a/kernel/delayacct.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/delayacct.c 2019-02-09 17:46:11.991297545 +0000 -@@ -115,7 +115,7 @@ - */ - 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; - -diff -Nur a/kernel/exit.c b/kernel/exit.c ---- a/kernel/exit.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/exit.c 2019-02-09 17:46:11.991297545 +0000 -@@ -130,7 +130,7 @@ - sig->curr_target = next_thread(tsk); - } - -- add_device_randomness((const void*) &tsk->se.sum_exec_runtime, -+ add_device_randomness((const void*) &tsk_seruntime(tsk), - sizeof(unsigned long long)); - - /* -@@ -151,7 +151,7 @@ - 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--; - __unhash_process(tsk, group_dead); - write_sequnlock(&sig->stats_lock); -diff -Nur a/kernel/kthread.c b/kernel/kthread.c ---- a/kernel/kthread.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/kthread.c 2019-02-09 17:46:11.991297545 +0000 -@@ -424,6 +424,34 @@ - } - EXPORT_SYMBOL(kthread_bind); - -+#if defined(CONFIG_SCHED_MUQSS) && defined(CONFIG_SMP) -+extern void __do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); -+ -+/* -+ * new_kthread_bind is a special variant of __kthread_bind_mask. -+ * For new threads to work on muqss we want to call do_set_cpus_allowed -+ * without the task_cpu being set and the task rescheduled until they're -+ * rescheduled on their own so we call __do_set_cpus_allowed directly which -+ * only changes the cpumask. This is particularly important for smpboot threads -+ * to work. -+ */ -+static void new_kthread_bind(struct task_struct *p, unsigned int cpu) -+{ -+ unsigned long flags; -+ -+ if (WARN_ON(!wait_task_inactive(p, TASK_UNINTERRUPTIBLE))) -+ return; -+ -+ /* It's safe because the task is inactive. */ -+ raw_spin_lock_irqsave(&p->pi_lock, flags); -+ __do_set_cpus_allowed(p, cpumask_of(cpu)); -+ p->flags |= PF_NO_SETAFFINITY; -+ raw_spin_unlock_irqrestore(&p->pi_lock, flags); -+} -+#else -+#define new_kthread_bind(p, cpu) kthread_bind(p, cpu) -+#endif -+ - /** - * kthread_create_on_cpu - Create a cpu bound kthread - * @threadfn: the function to run until signal_pending(current). -@@ -445,7 +473,7 @@ - cpu); - if (IS_ERR(p)) - return p; -- kthread_bind(p, cpu); -+ new_kthread_bind(p, cpu); - /* CPU hotplug need to bind once again when unparking the thread. */ - set_bit(KTHREAD_IS_PER_CPU, &to_kthread(p)->flags); - to_kthread(p)->cpu = cpu; -diff -Nur a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c ---- a/kernel/livepatch/transition.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/livepatch/transition.c 2019-02-09 17:46:11.991297545 +0000 -@@ -290,6 +290,12 @@ - return 0; - } - -+#ifdef CONFIG_SCHED_MUQSS -+typedef unsigned long rq_flags_t; -+#else -+typedef struct rq_flags rq_flag_t; -+#endif -+ - /* - * Try to safely switch a task to the target patch state. If it's currently - * running, or it's sleeping on a to-be-patched or to-be-unpatched function, or -@@ -298,7 +304,7 @@ - static bool klp_try_switch_task(struct task_struct *task) - { - struct rq *rq; -- struct rq_flags flags; -+ rq_flags_t flags; - int ret; - bool success = false; - char err_buf[STACK_ERR_BUF_SIZE]; -diff -Nur a/kernel/Makefile b/kernel/Makefile ---- a/kernel/Makefile 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/Makefile 2019-02-09 17:46:11.991297545 +0000 -@@ -10,7 +10,7 @@ - extable.o params.o \ - kthread.o sys_ni.o nsproxy.o \ - notifier.o ksysfs.o cred.o reboot.o \ -- async.o range.o smpboot.o ucount.o -+ async.o range.o smpboot.o ucount.o skip_list.o - - obj-$(CONFIG_MODULES) += kmod.o - obj-$(CONFIG_MULTIUSER) += groups.o -diff -Nur a/kernel/rcu/Kconfig b/kernel/rcu/Kconfig ---- a/kernel/rcu/Kconfig 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/rcu/Kconfig 2019-02-09 17:46:11.991297545 +0000 -@@ -93,7 +93,7 @@ - config CONTEXT_TRACKING_FORCE - bool "Force context tracking" - depends on CONTEXT_TRACKING -- default y if !NO_HZ_FULL -+ default y if !NO_HZ_FULL && !SCHED_MUQSS - help - The major pre-requirement for full dynticks to work is to - support the context tracking subsystem. But there are also -diff -Nur a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c ---- a/kernel/sched/cpufreq_schedutil.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/sched/cpufreq_schedutil.c 2019-02-09 17:46:12.001297867 +0000 -@@ -177,6 +177,12 @@ - return cpufreq_driver_resolve_freq(policy, freq); - } - -+#ifdef CONFIG_SCHED_MUQSS -+#define rt_rq_runnable(rq_rt) rt_rq_is_runnable(rq) -+#else -+#define rt_rq_runnable(rq_rt) rt_rq_is_runnable(&rq->rt) -+#endif -+ - /* - * This function computes an effective utilization for the given CPU, to be - * used for frequency selection given the linear relation: f = u * f_max. -@@ -205,7 +211,7 @@ - sg_cpu->max = max = arch_scale_cpu_capacity(NULL, sg_cpu->cpu); - sg_cpu->bw_dl = cpu_bw_dl(rq); - -- if (rt_rq_is_runnable(&rq->rt)) -+ if (rt_rq_runnable(rq)) - return max; - - /* -@@ -626,7 +632,11 @@ - struct task_struct *thread; - struct sched_attr attr = { - .size = sizeof(struct sched_attr), -+#ifdef CONFIG_SCHED_MUQSS -+ .sched_policy = SCHED_RR, -+#else - .sched_policy = SCHED_DEADLINE, -+#endif - .sched_flags = SCHED_FLAG_SUGOV, - .sched_nice = 0, - .sched_priority = 0, -diff -Nur a/kernel/sched/cpupri.h b/kernel/sched/cpupri.h ---- a/kernel/sched/cpupri.h 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/sched/cpupri.h 2019-02-09 17:46:12.001297867 +0000 -@@ -17,9 +17,11 @@ - int *cpu_to_pri; - }; - -+#ifndef CONFIG_SCHED_MUQSS - #ifdef CONFIG_SMP - int cpupri_find(struct cpupri *cp, struct task_struct *p, struct cpumask *lowest_mask); - void cpupri_set(struct cpupri *cp, int cpu, int pri); - int cpupri_init(struct cpupri *cp); - void cpupri_cleanup(struct cpupri *cp); - #endif -+#endif -diff -Nur a/kernel/sched/cputime.c b/kernel/sched/cputime.c ---- a/kernel/sched/cputime.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/sched/cputime.c 2019-02-09 17:46:12.001297867 +0000 -@@ -265,26 +265,6 @@ - return accounted; - } - --#ifdef CONFIG_64BIT --static inline u64 read_sum_exec_runtime(struct task_struct *t) --{ -- return t->se.sum_exec_runtime; --} --#else --static u64 read_sum_exec_runtime(struct task_struct *t) --{ -- u64 ns; -- struct rq_flags rf; -- struct rq *rq; -- -- rq = task_rq_lock(t, &rf); -- ns = t->se.sum_exec_runtime; -- task_rq_unlock(rq, t, &rf); -- -- return ns; --} --#endif -- - /* - * Accumulate raw cputime values of dead tasks (sig->[us]time) and live - * tasks (sum on group iteration) belonging to @tsk's group. -@@ -662,7 +642,7 @@ - void task_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st) - { - struct task_cputime cputime = { -- .sum_exec_runtime = p->se.sum_exec_runtime, -+ .sum_exec_runtime = tsk_seruntime(p), - }; - - task_cputime(p, &cputime.utime, &cputime.stime); -diff -Nur a/kernel/sched/idle.c b/kernel/sched/idle.c ---- a/kernel/sched/idle.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/sched/idle.c 2019-02-09 17:46:12.001297867 +0000 -@@ -224,6 +224,8 @@ - static void do_idle(void) - { - int cpu = smp_processor_id(); -+ bool pending = false; -+ - /* - * If the arch has a polling bit, we maintain an invariant: - * -@@ -234,7 +236,10 @@ - */ - - __current_set_polling(); -- tick_nohz_idle_enter(); -+ if (unlikely(softirq_pending(cpu))) -+ pending = true; -+ else -+ tick_nohz_idle_enter(); - - while (!need_resched()) { - check_pgt_cache(); -@@ -272,7 +277,8 @@ - * an IPI to fold the state for us. - */ - preempt_set_need_resched(); -- tick_nohz_idle_exit(); -+ if (!pending) -+ tick_nohz_idle_exit(); - __current_clr_polling(); - - /* -@@ -368,6 +374,7 @@ - do_idle(); - } - -+#ifndef CONFIG_SCHED_MUQSS - /* - * idle-task scheduling class. - */ -@@ -480,3 +487,4 @@ - .switched_to = switched_to_idle, - .update_curr = update_curr_idle, - }; -+#endif /* CONFIG_SCHED_MUQSS */ -diff -Nur a/kernel/sched/Makefile b/kernel/sched/Makefile ---- a/kernel/sched/Makefile 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/sched/Makefile 2019-02-09 17:46:11.991297545 +0000 -@@ -16,6 +16,17 @@ - CFLAGS_core.o := $(PROFILING) -fno-omit-frame-pointer - endif - -+ifdef CONFIG_SCHED_MUQSS -+obj-y += MuQSS.o clock.o cputime.o -+obj-y += idle.o -+obj-y += wait.o wait_bit.o swait.o completion.o -+ -+obj-$(CONFIG_SMP) += topology.o -+obj-$(CONFIG_SCHEDSTATS) += stats.o -+obj-$(CONFIG_CPU_FREQ) += cpufreq.o -+obj-$(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) += cpufreq_schedutil.o -+obj-$(CONFIG_CPU_ISOLATION) += isolation.o -+else - obj-y += core.o loadavg.o clock.o cputime.o - obj-y += idle.o fair.o rt.o deadline.o - obj-y += wait.o wait_bit.o swait.o completion.o -@@ -29,3 +40,4 @@ - obj-$(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) += cpufreq_schedutil.o - obj-$(CONFIG_MEMBARRIER) += membarrier.o - obj-$(CONFIG_CPU_ISOLATION) += isolation.o -+endif -diff -Nur a/kernel/sched/MuQSS.c b/kernel/sched/MuQSS.c ---- a/kernel/sched/MuQSS.c 1970-01-01 01:00:00.000000000 +0100 -+++ b/kernel/sched/MuQSS.c 2019-02-09 17:46:12.001297867 +0000 -@@ -0,0 +1,7366 @@ -+// SPDX-License-Identifier: GPL-2.0 -+/* -+ * kernel/sched/MuQSS.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 -+ * 2009-08-13 Brainfuck deadline scheduling policy by Con Kolivas deletes -+ * a whole lot of those previous things. -+ * 2016-10-01 Multiple Queue Skiplist Scheduler scalable evolution of BFS -+ * scheduler by Con Kolivas. -+ */ -+ -+#include <linux/sched/isolation.h> -+#include <linux/sched/loadavg.h> -+ -+#include <linux/binfmts.h> -+#include <linux/blkdev.h> -+#include <linux/compat.h> -+#include <linux/context_tracking.h> -+#include <linux/cpuset.h> -+#include <linux/delayacct.h> -+#include <linux/init_task.h> -+#include <linux/kcov.h> -+#include <linux/kprobes.h> -+#include <linux/mmu_context.h> -+#include <linux/module.h> -+#include <linux/nmi.h> -+#include <linux/prefetch.h> -+#include <linux/profile.h> -+#include <linux/rcupdate_wait.h> -+#include <linux/sched.h> -+#include <linux/security.h> -+#include <linux/skip_list.h> -+#include <linux/syscalls.h> -+#include <linux/tick.h> -+#include <linux/wait_bit.h> -+ -+#include <asm/irq_regs.h> -+#include <asm/switch_to.h> -+#include <asm/tlb.h> -+ -+#include "../workqueue_internal.h" -+#include "../smpboot.h" -+ -+#define CREATE_TRACE_POINTS -+#include <trace/events/sched.h> -+ -+#include "MuQSS.h" -+ -+#define rt_prio(prio) unlikely((prio) < MAX_RT_PRIO) -+#define rt_task(p) rt_prio((p)->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 is_idle_policy(policy) ((policy) == SCHED_IDLEPRIO) -+#define idleprio_task(p) unlikely(is_idle_policy((p)->policy)) -+#define task_running_idle(p) unlikely((p)->prio == IDLE_PRIO) -+ -+#define is_iso_policy(policy) ((policy) == SCHED_ISO) -+#define iso_task(p) unlikely(is_iso_policy((p)->policy)) -+#define task_running_iso(p) unlikely((p)->prio == ISO_PRIO) -+ -+#define rq_idle(rq) ((rq)->rq_prio == PRIO_LIMIT) -+ -+#define ISO_PERIOD (5 * HZ) -+ -+#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 APPROX_NS_PS (1073741824) /* Approximate ns per second */ -+#define JIFFIES_TO_NS(TIME) ((TIME) * (APPROX_NS_PS / HZ)) -+#define JIFFY_NS (APPROX_NS_PS / HZ) -+#define JIFFY_US (1048576 / HZ) -+#define NS_TO_JIFFIES(TIME) ((TIME) / JIFFY_NS) -+#define HALF_JIFFY_NS (APPROX_NS_PS / HZ / 2) -+#define HALF_JIFFY_US (1048576 / 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 US_TO_NS(TIME) ((TIME) << 10) -+#define TICK_APPROX_NS ((APPROX_NS_PS+HZ/2)/HZ) -+ -+#define RESCHED_US (100) /* Reschedule if less than this many μs left */ -+ -+void print_scheduler_version(void) -+{ -+ printk(KERN_INFO "MuQSS CPU scheduler v0.180 by Con Kolivas.\n"); -+} -+ -+#define RQSHARE_NONE 0 -+#define RQSHARE_SMT 1 -+#define RQSHARE_MC 2 -+#define RQSHARE_SMP 3 -+ -+/* -+ * This determines what level of runqueue sharing will be done and is -+ * configurable at boot time with the bootparam rqshare = -+ */ -+static int rqshare __read_mostly = CONFIG_SHARERQ; /* Default RQSHARE_MC */ -+ -+static int __init set_rqshare(char *str) -+{ -+ if (!strncmp(str, "none", 4)) { -+ rqshare = RQSHARE_NONE; -+ return 0; -+ } -+ if (!strncmp(str, "smt", 3)) { -+ rqshare = RQSHARE_SMT; -+ return 0; -+ } -+ if (!strncmp(str, "mc", 2)) { -+ rqshare = RQSHARE_MC; -+ return 0; -+ } -+ if (!strncmp(str, "smp", 2)) { -+ rqshare = RQSHARE_SMP; -+ return 0; -+ } -+ return 1; -+} -+__setup("rqshare=", set_rqshare); -+ -+/* -+ * This is the time all tasks within the same priority round robin. -+ * Value is in ms and set to a minimum of 6ms. -+ * Tunable via /proc interface. -+ */ -+int rr_interval __read_mostly = 6; -+ -+/* -+ * Tunable to choose whether to prioritise latency or throughput, simple -+ * binary yes or no -+ */ -+int sched_interactive __read_mostly = 1; -+ -+/* -+ * 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; -+ -+/* -+ * sched_yield_type - Choose what sort of yield sched_yield will perform. -+ * 0: No yield. -+ * 1: Yield only to better priority/deadline tasks. (default) -+ * 2: Expire timeslice and recalculate deadline. -+ */ -+int sched_yield_type __read_mostly = 1; -+ -+/* -+ * The relative length of deadline for each priority(nice) level. -+ */ -+static int prio_ratios[NICE_WIDTH] __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); -+} -+ -+DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); -+ -+#ifdef CONFIG_SMP -+/* -+ * Total number of runqueues. Equals number of CPUs when there is no runqueue -+ * sharing but is usually less with SMT/MC sharing of runqueues. -+ */ -+static int total_runqueues __read_mostly = 1; -+ -+static cpumask_t cpu_idle_map ____cacheline_aligned_in_smp; -+ -+struct rq *cpu_rq(int cpu) -+{ -+ return &per_cpu(runqueues, (cpu)); -+} -+#define cpu_curr(cpu) (cpu_rq(cpu)->curr) -+ -+/* -+ * For asym packing, by default the lower numbered cpu has higher priority. -+ */ -+int __weak arch_asym_cpu_priority(int cpu) -+{ -+ return -cpu; -+} -+ -+int __weak arch_sd_sibling_asym_packing(void) -+{ -+ return 0*SD_ASYM_PACKING; -+} -+#else -+struct rq *uprq; -+#endif /* CONFIG_SMP */ -+ -+#include "stats.h" -+ -+/* -+ * All common locking functions performed on rq->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 rq->lock to be safe. -+ */ -+ -+/* -+ * RQ-clock updating methods: -+ */ -+ -+#ifdef HAVE_SCHED_AVG_IRQ -+static void update_irq_load_avg(struct rq *rq, long delta); -+#else -+static inline void update_irq_load_avg(struct rq *rq, long delta) {} -+#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... -+ */ -+#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING) -+ s64 steal = 0, irq_delta = 0; -+#endif -+#ifdef CONFIG_IRQ_TIME_ACCOUNTING -+ 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))) { -+ steal = paravirt_steal_clock(cpu_of(rq)); -+ steal -= rq->prev_steal_time_rq; -+ -+ if (unlikely(steal > delta)) -+ steal = delta; -+ -+ rq->prev_steal_time_rq += steal; -+ delta -= steal; -+ } -+#endif -+ rq->clock_task += delta; -+ -+#ifdef HAVE_SCHED_AVG_IRQ -+ if (irq_delta + steal) -+ update_irq_load_avg(rq, irq_delta + steal); -+#endif -+} -+ -+static inline void update_rq_clock(struct rq *rq) -+{ -+ s64 delta = sched_clock_cpu(cpu_of(rq)) - rq->clock; -+ -+ if (unlikely(delta < 0)) -+ return; -+ rq->clock += delta; -+ update_rq_clock_task(rq, delta); -+} -+ -+/* -+ * Niffies are a globally increasing nanosecond counter. They're only used by -+ * update_load_avg and time_slice_expired, however deadlines are based on them -+ * across CPUs. Update them whenever we will call one of those functions, and -+ * synchronise them across CPUs whenever we hold both runqueue locks. -+ */ -+static inline void update_clocks(struct rq *rq) -+{ -+ s64 ndiff, minndiff; -+ long jdiff; -+ -+ update_rq_clock(rq); -+ ndiff = rq->clock - rq->old_clock; -+ rq->old_clock = rq->clock; -+ jdiff = jiffies - rq->last_jiffy; -+ -+ /* Subtract any niffies added by balancing with other rqs */ -+ ndiff -= rq->niffies - rq->last_niffy; -+ minndiff = JIFFIES_TO_NS(jdiff) - rq->niffies + rq->last_jiffy_niffies; -+ if (minndiff < 0) -+ minndiff = 0; -+ ndiff = max(ndiff, minndiff); -+ rq->niffies += ndiff; -+ rq->last_niffy = rq->niffies; -+ if (jdiff) { -+ rq->last_jiffy += jdiff; -+ rq->last_jiffy_niffies = rq->niffies; -+ } -+} -+ -+static inline int task_on_rq_queued(struct task_struct *p) -+{ -+ return p->on_rq == TASK_ON_RQ_QUEUED; -+} -+ -+static inline int task_on_rq_migrating(struct task_struct *p) -+{ -+ return p->on_rq == TASK_ON_RQ_MIGRATING; -+} -+ -+/* -+ * Any time we have two runqueues locked we use that as an opportunity to -+ * synchronise niffies to the highest value as idle ticks may have artificially -+ * kept niffies low on one CPU and the truth can only be later. -+ */ -+static inline void synchronise_niffies(struct rq *rq1, struct rq *rq2) -+{ -+ if (rq1->niffies > rq2->niffies) -+ rq2->niffies = rq1->niffies; -+ else -+ rq1->niffies = rq2->niffies; -+} -+ -+/* -+ * double_rq_lock - safely lock two runqueues -+ * -+ * Note this does not disable interrupts like task_rq_lock, -+ * you need to do so manually before calling. -+ */ -+ -+/* For when we know rq1 != rq2 */ -+static inline void __double_rq_lock(struct rq *rq1, struct rq *rq2) -+ __acquires(rq1->lock) -+ __acquires(rq2->lock) -+{ -+ if (rq1 < rq2) { -+ raw_spin_lock(rq1->lock); -+ raw_spin_lock_nested(rq2->lock, SINGLE_DEPTH_NESTING); -+ } else { -+ raw_spin_lock(rq2->lock); -+ raw_spin_lock_nested(rq1->lock, SINGLE_DEPTH_NESTING); -+ } -+} -+ -+static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) -+ __acquires(rq1->lock) -+ __acquires(rq2->lock) -+{ -+ BUG_ON(!irqs_disabled()); -+ if (rq1->lock == rq2->lock) { -+ raw_spin_lock(rq1->lock); -+ __acquire(rq2->lock); /* Fake it out ;) */ -+ } else -+ __double_rq_lock(rq1, rq2); -+ synchronise_niffies(rq1, rq2); -+} -+ -+/* -+ * double_rq_unlock - safely unlock two runqueues -+ * -+ * Note this does not restore interrupts like task_rq_unlock, -+ * you need to do so manually after calling. -+ */ -+static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) -+ __releases(rq1->lock) -+ __releases(rq2->lock) -+{ -+ raw_spin_unlock(rq1->lock); -+ if (rq1->lock != rq2->lock) -+ raw_spin_unlock(rq2->lock); -+ else -+ __release(rq2->lock); -+} -+ -+static inline void lock_all_rqs(void) -+{ -+ int cpu; -+ -+ preempt_disable(); -+ for_each_possible_cpu(cpu) { -+ struct rq *rq = cpu_rq(cpu); -+ -+ do_raw_spin_lock(rq->lock); -+ } -+} -+ -+static inline void unlock_all_rqs(void) -+{ -+ int cpu; -+ -+ for_each_possible_cpu(cpu) { -+ struct rq *rq = cpu_rq(cpu); -+ -+ do_raw_spin_unlock(rq->lock); -+ } -+ preempt_enable(); -+} -+ -+/* Specially nest trylock an rq */ -+static inline bool trylock_rq(struct rq *this_rq, struct rq *rq) -+{ -+ if (unlikely(!do_raw_spin_trylock(rq->lock))) -+ return false; -+ spin_acquire(rq->lock.dep_map, SINGLE_DEPTH_NESTING, 1, _RET_IP_); -+ synchronise_niffies(this_rq, rq); -+ return true; -+} -+ -+/* Unlock a specially nested trylocked rq */ -+static inline void unlock_rq(struct rq *rq) -+{ -+ spin_release(rq->lock.dep_map, 1, _RET_IP_); -+ do_raw_spin_unlock(rq->lock); -+} -+ -+/* -+ * cmpxchg based fetch_or, macro so it works for different integer types -+ */ -+#define fetch_or(ptr, mask) \ -+ ({ \ -+ typeof(ptr) _ptr = (ptr); \ -+ typeof(mask) _mask = (mask); \ -+ typeof(*_ptr) _old, _val = *_ptr; \ -+ \ -+ for (;;) { \ -+ _old = cmpxchg(_ptr, _val, _val | _mask); \ -+ if (_old == _val) \ -+ break; \ -+ _val = _old; \ -+ } \ -+ _old; \ -+}) -+ -+#if defined(CONFIG_SMP) && defined(TIF_POLLING_NRFLAG) -+/* -+ * Atomically set TIF_NEED_RESCHED and test for TIF_POLLING_NRFLAG, -+ * this avoids any races wrt polling state changes and thereby avoids -+ * spurious IPIs. -+ */ -+static bool set_nr_and_not_polling(struct task_struct *p) -+{ -+ struct thread_info *ti = task_thread_info(p); -+ return !(fetch_or(&ti->flags, _TIF_NEED_RESCHED) & _TIF_POLLING_NRFLAG); -+} -+ -+/* -+ * Atomically set TIF_NEED_RESCHED if TIF_POLLING_NRFLAG is set. -+ * -+ * If this returns true, then the idle task promises to call -+ * sched_ttwu_pending() and reschedule soon. -+ */ -+static bool set_nr_if_polling(struct task_struct *p) -+{ -+ struct thread_info *ti = task_thread_info(p); -+ typeof(ti->flags) old, val = READ_ONCE(ti->flags); -+ -+ for (;;) { -+ if (!(val & _TIF_POLLING_NRFLAG)) -+ return false; -+ if (val & _TIF_NEED_RESCHED) -+ return true; -+ old = cmpxchg(&ti->flags, val, val | _TIF_NEED_RESCHED); -+ if (old == val) -+ break; -+ val = old; -+ } -+ return true; -+} -+ -+#else -+static bool set_nr_and_not_polling(struct task_struct *p) -+{ -+ set_tsk_need_resched(p); -+ return true; -+} -+ -+#ifdef CONFIG_SMP -+static bool set_nr_if_polling(struct task_struct *p) -+{ -+ return false; -+} -+#endif -+#endif -+ -+void wake_q_add(struct wake_q_head *head, struct task_struct *task) -+{ -+ struct wake_q_node *node = &task->wake_q; -+ -+ /* -+ * Atomically grab the task, if ->wake_q is !nil already it means -+ * its already queued (either by us or someone else) and will get the -+ * wakeup due to that. -+ * -+ * This cmpxchg() executes a full barrier, which pairs with the full -+ * barrier executed by the wakeup in wake_up_q(). -+ */ -+ if (cmpxchg(&node->next, NULL, WAKE_Q_TAIL)) -+ return; -+ -+ get_task_struct(task); -+ -+ /* -+ * The head is context local, there can be no concurrency. -+ */ -+ *head->lastp = node; -+ head->lastp = &node->next; -+} -+ -+void wake_up_q(struct wake_q_head *head) -+{ -+ struct wake_q_node *node = head->first; -+ -+ while (node != WAKE_Q_TAIL) { -+ struct task_struct *task; -+ -+ task = container_of(node, struct task_struct, wake_q); -+ BUG_ON(!task); -+ /* Task can safely be re-inserted now */ -+ node = node->next; -+ task->wake_q.next = NULL; -+ -+ /* -+ * wake_up_process() executes a full barrier, which pairs with -+ * the queueing in wake_q_add() so as not to miss wakeups. -+ */ -+ wake_up_process(task); -+ put_task_struct(task); -+ } -+} -+ -+static inline void smp_sched_reschedule(int cpu) -+{ -+ if (likely(cpu_online(cpu))) -+ smp_send_reschedule(cpu); -+} -+ -+/* -+ * 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. -+ */ -+void resched_task(struct task_struct *p) -+{ -+ int cpu; -+#ifdef CONFIG_LOCKDEP -+ /* Kernel threads call this when creating workqueues while still -+ * inactive from __kthread_bind_mask, holding only the pi_lock */ -+ if (!(p->flags & PF_KTHREAD)) { -+ struct rq *rq = task_rq(p); -+ -+ lockdep_assert_held(rq->lock); -+ } -+#endif -+ if (test_tsk_need_resched(p)) -+ return; -+ -+ cpu = task_cpu(p); -+ if (cpu == smp_processor_id()) { -+ set_tsk_need_resched(p); -+ set_preempt_need_resched(); -+ return; -+ } -+ -+ if (set_nr_and_not_polling(p)) -+ smp_sched_reschedule(cpu); -+ else -+ trace_sched_wake_idle_without_ipi(cpu); -+} -+ -+/* -+ * A task that is not running or queued will not have a node set. -+ * A task that is queued but not running will have a node set. -+ * A task that is currently running will have ->on_cpu set but no node set. -+ */ -+static inline bool task_queued(struct task_struct *p) -+{ -+ return !skiplist_node_empty(&p->node); -+} -+ -+static void enqueue_task(struct rq *rq, struct task_struct *p, int flags); -+static inline void resched_if_idle(struct rq *rq); -+ -+/* Dodgy workaround till we figure out where the softirqs are going */ -+static inline void do_pending_softirq(struct rq *rq, struct task_struct *next) -+{ -+ if (unlikely(next == rq->idle && local_softirq_pending() && !in_interrupt())) -+ do_softirq_own_stack(); -+} -+ -+static inline bool deadline_before(u64 deadline, u64 time) -+{ -+ return (deadline < time); -+} -+ -+/* -+ * 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()); -+} -+ -+static inline bool rq_local(struct rq *rq); -+ -+#ifndef SCHED_CAPACITY_SCALE -+#define SCHED_CAPACITY_SCALE 1024 -+#endif -+ -+static inline int rq_load(struct rq *rq) -+{ -+ return rq->nr_running; -+} -+ -+/* -+ * Update the load average for feeding into cpu frequency governors. Use a -+ * rough estimate of a rolling average with ~ time constant of 32ms. -+ * 80/128 ~ 0.63. * 80 / 32768 / 128 == * 5 / 262144 -+ * Make sure a call to update_clocks has been made before calling this to get -+ * an updated rq->niffies. -+ */ -+static void update_load_avg(struct rq *rq, unsigned int flags) -+{ -+ long us_interval, load; -+ unsigned long curload; -+ -+ us_interval = NS_TO_US(rq->niffies - rq->load_update); -+ if (unlikely(us_interval <= 0)) -+ return; -+ -+ curload = rq_load(rq); -+ load = rq->load_avg - (rq->load_avg * us_interval * 5 / 262144); -+ if (unlikely(load < 0)) -+ load = 0; -+ load += curload * curload * SCHED_CAPACITY_SCALE * us_interval * 5 / 262144; -+ rq->load_avg = load; -+ -+ rq->load_update = rq->niffies; -+ update_irq_load_avg(rq, 0); -+ if (likely(rq_local(rq))) -+ cpufreq_trigger(rq, flags); -+} -+ -+#ifdef HAVE_SCHED_AVG_IRQ -+/* -+ * IRQ variant of update_load_avg below. delta is actually time in nanoseconds -+ * here so we scale curload to how long it's been since the last update. -+ */ -+static void update_irq_load_avg(struct rq *rq, long delta) -+{ -+ long us_interval, load; -+ unsigned long curload; -+ -+ us_interval = NS_TO_US(rq->niffies - rq->irq_load_update); -+ if (unlikely(us_interval <= 0)) -+ return; -+ -+ curload = NS_TO_US(delta) / us_interval; -+ load = rq->irq_load_avg - (rq->irq_load_avg * us_interval * 5 / 262144); -+ if (unlikely(load < 0)) -+ load = 0; -+ load += curload * curload * SCHED_CAPACITY_SCALE * us_interval * 5 / 262144; -+ rq->irq_load_avg = load; -+ -+ rq->irq_load_update = rq->niffies; -+} -+#endif -+ -+/* -+ * Removing from the runqueue. Enter with rq locked. Deleting a task -+ * from the skip list is done via the stored node reference in the task struct -+ * and does not require a full look up. Thus it occurs in O(k) time where k -+ * is the "level" of the list the task was stored at - usually < 4, max 8. -+ */ -+static void dequeue_task(struct rq *rq, struct task_struct *p, int flags) -+{ -+ skiplist_delete(rq->sl, &p->node); -+ rq->best_key = rq->node->next[0]->key; -+ update_clocks(rq); -+ -+ if (!(flags & DEQUEUE_SAVE)) -+ sched_info_dequeued(task_rq(p), p); -+ rq->nr_running--; -+ if (rt_task(p)) -+ rq->rt_nr_running--; -+ update_load_avg(rq, flags); -+} -+ -+#ifdef CONFIG_PREEMPT_RCU -+static bool rcu_read_critical(struct task_struct *p) -+{ -+ return p->rcu_read_unlock_special.b.blocked; -+} -+#else /* CONFIG_PREEMPT_RCU */ -+#define rcu_read_critical(p) (false) -+#endif /* CONFIG_PREEMPT_RCU */ -+ -+/* -+ * 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 (!(task_contributes_to_load(p)) && !(p->flags & (PF_EXITING)) && -+ !signal_pending(p) && !rcu_read_critical(p) && !freezing(p)); -+} -+ -+/* -+ * To determine if a task of SCHED_ISO can run in pseudo-realtime, we check -+ * that the iso_refractory flag is not set. -+ */ -+static inline bool isoprio_suitable(struct rq *rq) -+{ -+ return !rq->iso_refractory; -+} -+ -+/* -+ * Adding to the runqueue. Enter with rq locked. -+ */ -+static void enqueue_task(struct rq *rq, struct task_struct *p, int flags) -+{ -+ unsigned int randseed, cflags = 0; -+ u64 sl_id; -+ -+ if (!rt_task(p)) { -+ /* Check it hasn't gotten rt from PI */ -+ if ((idleprio_task(p) && idleprio_suitable(p)) || -+ (iso_task(p) && isoprio_suitable(rq))) -+ p->prio = p->normal_prio; -+ else -+ p->prio = NORMAL_PRIO; -+ } else -+ rq->rt_nr_running++; -+ /* -+ * The sl_id key passed to the skiplist generates a sorted list. -+ * Realtime and sched iso tasks run FIFO so they only need be sorted -+ * according to priority. The skiplist will put tasks of the same -+ * key inserted later in FIFO order. Tasks of sched normal, batch -+ * and idleprio are sorted according to their deadlines. Idleprio -+ * tasks are offset by an impossibly large deadline value ensuring -+ * they get sorted into last positions, but still according to their -+ * own deadlines. This creates a "landscape" of skiplists running -+ * from priority 0 realtime in first place to the lowest priority -+ * idleprio tasks last. Skiplist insertion is an O(log n) process. -+ */ -+ if (p->prio <= ISO_PRIO) { -+ sl_id = p->prio; -+ } else { -+ sl_id = p->deadline; -+ if (idleprio_task(p)) { -+ if (p->prio == IDLE_PRIO) -+ sl_id |= 0xF000000000000000; -+ else -+ sl_id += longest_deadline_diff(); -+ } -+ } -+ /* -+ * Some architectures don't have better than microsecond resolution -+ * so mask out ~microseconds as the random seed for skiplist insertion. -+ */ -+ update_clocks(rq); -+ if (!(flags & ENQUEUE_RESTORE)) -+ sched_info_queued(rq, p); -+ randseed = (rq->niffies >> 10) & 0xFFFFFFFF; -+ skiplist_insert(rq->sl, &p->node, sl_id, p, randseed); -+ rq->best_key = rq->node->next[0]->key; -+ if (p->in_iowait) -+ cflags |= SCHED_CPUFREQ_IOWAIT; -+ rq->nr_running++; -+ update_load_avg(rq, cflags); -+} -+ -+/* -+ * 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 -+/* Entered with rq locked */ -+static inline void resched_if_idle(struct rq *rq) -+{ -+ if (rq_idle(rq)) -+ resched_task(rq->curr); -+} -+ -+static inline bool rq_local(struct rq *rq) -+{ -+ return (rq->cpu == smp_processor_id()); -+} -+#ifdef CONFIG_SMT_NICE -+static const cpumask_t *thread_cpumask(int cpu); -+ -+/* Find the best real time priority running on any SMT siblings of cpu and if -+ * none are running, the static priority of the best deadline task running. -+ * The lookups to the other runqueues is done lockless as the occasional wrong -+ * value would be harmless. */ -+static int best_smt_bias(struct rq *this_rq) -+{ -+ int other_cpu, best_bias = 0; -+ -+ for_each_cpu(other_cpu, &this_rq->thread_mask) { -+ struct rq *rq = cpu_rq(other_cpu); -+ -+ if (rq_idle(rq)) -+ continue; -+ if (unlikely(!rq->online)) -+ continue; -+ if (!rq->rq_mm) -+ continue; -+ if (likely(rq->rq_smt_bias > best_bias)) -+ best_bias = rq->rq_smt_bias; -+ } -+ return best_bias; -+} -+ -+static int task_prio_bias(struct task_struct *p) -+{ -+ if (rt_task(p)) -+ return 1 << 30; -+ else if (task_running_iso(p)) -+ return 1 << 29; -+ else if (task_running_idle(p)) -+ return 0; -+ return MAX_PRIO - p->static_prio; -+} -+ -+static bool smt_always_schedule(struct task_struct __maybe_unused *p, struct rq __maybe_unused *this_rq) -+{ -+ return true; -+} -+ -+static bool (*smt_schedule)(struct task_struct *p, struct rq *this_rq) = &smt_always_schedule; -+ -+/* We've already decided p can run on CPU, now test if it shouldn't for SMT -+ * nice reasons. */ -+static bool smt_should_schedule(struct task_struct *p, struct rq *this_rq) -+{ -+ int best_bias, task_bias; -+ -+ /* Kernel threads always run */ -+ if (unlikely(!p->mm)) -+ return true; -+ if (rt_task(p)) -+ return true; -+ if (!idleprio_suitable(p)) -+ return true; -+ best_bias = best_smt_bias(this_rq); -+ /* The smt siblings are all idle or running IDLEPRIO */ -+ if (best_bias < 1) -+ return true; -+ task_bias = task_prio_bias(p); -+ if (task_bias < 1) -+ return false; -+ if (task_bias >= best_bias) -+ return true; -+ /* Dither 25% cpu of normal tasks regardless of nice difference */ -+ if (best_bias % 4 == 1) -+ return true; -+ /* Sorry, you lose */ -+ return false; -+} -+#else /* CONFIG_SMT_NICE */ -+#define smt_schedule(p, this_rq) (true) -+#endif /* CONFIG_SMT_NICE */ -+ -+static inline void atomic_set_cpu(int cpu, cpumask_t *cpumask) -+{ -+ set_bit(cpu, (volatile unsigned long *)cpumask); -+} -+ -+/* -+ * 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. The -+ * bits are set atomically but read locklessly as occasional false positive / -+ * negative is harmless. -+ */ -+static inline void set_cpuidle_map(int cpu) -+{ -+ if (likely(cpu_online(cpu))) -+ atomic_set_cpu(cpu, &cpu_idle_map); -+} -+ -+static inline void atomic_clear_cpu(int cpu, cpumask_t *cpumask) -+{ -+ clear_bit(cpu, (volatile unsigned long *)cpumask); -+} -+ -+static inline void clear_cpuidle_map(int cpu) -+{ -+ atomic_clear_cpu(cpu, &cpu_idle_map); -+} -+ -+static bool suitable_idle_cpus(struct task_struct *p) -+{ -+ return (cpumask_intersects(&p->cpus_allowed, &cpu_idle_map)); -+} -+ -+/* -+ * Resched current on rq. We don't know if rq is local to this CPU nor if it -+ * is locked so we do not use an intermediate variable for the task to avoid -+ * having it dereferenced. -+ */ -+static void resched_curr(struct rq *rq) -+{ -+ int cpu; -+ -+ if (test_tsk_need_resched(rq->curr)) -+ return; -+ -+ rq->preempt = rq->curr; -+ cpu = rq->cpu; -+ -+ /* We're doing this without holding the rq lock if it's not task_rq */ -+ -+ if (cpu == smp_processor_id()) { -+ set_tsk_need_resched(rq->curr); -+ set_preempt_need_resched(); -+ return; -+ } -+ -+ if (set_nr_and_not_polling(rq->curr)) -+ smp_sched_reschedule(cpu); -+ else -+ trace_sched_wake_idle_without_ipi(cpu); -+} -+ -+#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) -+ -+/* -+ * 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 thread, 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 int best_mask_cpu(int best_cpu, struct rq *rq, cpumask_t *tmpmask) -+{ -+ 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 (cpumask_test_cpu(best_cpu, tmpmask)) -+ goto out; -+ -+ for_each_cpu(cpu_tmp, tmpmask) { -+ int ranking, locality; -+ struct rq *tmp_rq; -+ -+ ranking = 0; -+ tmp_rq = cpu_rq(cpu_tmp); -+ -+ locality = rq->cpu_locality[cpu_tmp]; -+#ifdef CONFIG_NUMA -+ if (locality > 3) -+ ranking |= CPUIDLE_DIFF_NODE; -+ else -+#endif -+ if (locality > 2) -+ ranking |= CPUIDLE_DIFF_CPU; -+#ifdef CONFIG_SCHED_MC -+ else if (locality == 2) -+ ranking |= CPUIDLE_DIFF_CORE; -+ else if (!(tmp_rq->cache_idle(tmp_rq))) -+ ranking |= CPUIDLE_CACHE_BUSY; -+#endif -+#ifdef CONFIG_SCHED_SMT -+ if (locality == 1) -+ ranking |= CPUIDLE_DIFF_THREAD; -+ if (!(tmp_rq->siblings_idle(tmp_rq))) -+ ranking |= CPUIDLE_THREAD_BUSY; -+#endif -+ if (ranking < best_ranking) { -+ best_cpu = cpu_tmp; -+ best_ranking = ranking; -+ } -+ } -+out: -+ return best_cpu; -+} -+ -+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); -+} -+ -+/* As per resched_curr but only will resched idle task */ -+static inline void resched_idle(struct rq *rq) -+{ -+ if (test_tsk_need_resched(rq->idle)) -+ return; -+ -+ rq->preempt = rq->idle; -+ -+ set_tsk_need_resched(rq->idle); -+ -+ if (rq_local(rq)) { -+ set_preempt_need_resched(); -+ return; -+ } -+ -+ smp_sched_reschedule(rq->cpu); -+} -+ -+static struct rq *resched_best_idle(struct task_struct *p, int cpu) -+{ -+ cpumask_t tmpmask; -+ struct rq *rq; -+ int best_cpu; -+ -+ cpumask_and(&tmpmask, &p->cpus_allowed, &cpu_idle_map); -+ best_cpu = best_mask_cpu(cpu, task_rq(p), &tmpmask); -+ rq = cpu_rq(best_cpu); -+ if (!smt_schedule(p, rq)) -+ return NULL; -+ rq->preempt = p; -+ resched_idle(rq); -+ return rq; -+} -+ -+static inline void resched_suitable_idle(struct task_struct *p) -+{ -+ if (suitable_idle_cpus(p)) -+ resched_best_idle(p, task_cpu(p)); -+} -+ -+static inline struct rq *rq_order(struct rq *rq, int cpu) -+{ -+ return rq->rq_order[cpu]; -+} -+#else /* CONFIG_SMP */ -+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) -+{ -+} -+ -+static inline void resched_curr(struct rq *rq) -+{ -+ resched_task(rq->curr); -+} -+ -+static inline void resched_if_idle(struct rq *rq) -+{ -+} -+ -+static inline bool rq_local(struct rq *rq) -+{ -+ return true; -+} -+ -+static inline struct rq *rq_order(struct rq *rq, int cpu) -+{ -+ return rq; -+} -+ -+static inline bool smt_schedule(struct task_struct *p, struct rq *rq) -+{ -+ return true; -+} -+#endif /* CONFIG_SMP */ -+ -+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 rq locked. -+ */ -+static void activate_task(struct task_struct *p, struct rq *rq) -+{ -+ resched_if_idle(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->niffies - p->last_ran) >> 20); -+ } -+ -+ p->prio = effective_prio(p); -+ if (task_contributes_to_load(p)) -+ rq->nr_uninterruptible--; -+ -+ enqueue_task(rq, p, 0); -+ p->on_rq = TASK_ON_RQ_QUEUED; -+} -+ -+/* -+ * deactivate_task - If it's running, it's not on the runqueue and we can just -+ * decrement the nr_running. Enter with rq locked. -+ */ -+static inline void deactivate_task(struct task_struct *p, struct rq *rq) -+{ -+ if (task_contributes_to_load(p)) -+ rq->nr_uninterruptible++; -+ -+ p->on_rq = 0; -+ sched_info_dequeued(rq, p); -+} -+ -+#ifdef CONFIG_SMP -+void set_task_cpu(struct task_struct *p, unsigned int new_cpu) -+{ -+ struct rq *rq; -+ -+ if (task_cpu(p) == new_cpu) -+ return; -+ -+ /* Do NOT call set_task_cpu on a currently queued task as we will not -+ * be reliably holding the rq lock after changing CPU. */ -+ BUG_ON(task_queued(p)); -+ rq = task_rq(p); -+ -+#ifdef CONFIG_LOCKDEP -+ /* -+ * The caller should hold either p->pi_lock or rq->lock, when changing -+ * a task's CPU. ->pi_lock for waking tasks, rq->lock for runnable tasks. -+ * -+ * Furthermore, all task_rq users should acquire both locks, see -+ * task_rq_lock(). -+ */ -+ WARN_ON_ONCE(debug_locks && !(lockdep_is_held(&p->pi_lock) || -+ lockdep_is_held(rq->lock))); -+#endif -+ -+ trace_sched_migrate_task(p, new_cpu); -+ rseq_migrate(p); -+ perf_event_task_migrate(p); -+ -+ /* -+ * After ->cpu is set up to a new value, task_rq_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(); -+ -+ p->wake_cpu = new_cpu; -+ -+ if (task_running(rq, p)) { -+ /* -+ * We should only be calling this on a running task if we're -+ * holding rq lock. -+ */ -+ lockdep_assert_held(rq->lock); -+ -+ /* -+ * We can't change the task_thread_info CPU on a running task -+ * as p will still be protected by the rq lock of the CPU it -+ * is still running on so we only set the wake_cpu for it to be -+ * lazily updated once off the CPU. -+ */ -+ return; -+ } -+ -+#ifdef CONFIG_THREAD_INFO_IN_TASK -+ p->cpu = new_cpu; -+#else -+ task_thread_info(p)->cpu = new_cpu; -+#endif -+ /* We're no longer protecting p after this point since we're holding -+ * the wrong runqueue lock. */ -+} -+#endif /* CONFIG_SMP */ -+ -+/* -+ * Move a task off the runqueue and take it to a cpu for it will -+ * become the running task. -+ */ -+static inline void take_task(struct rq *rq, int cpu, struct task_struct *p) -+{ -+ struct rq *p_rq = task_rq(p); -+ -+ dequeue_task(p_rq, p, DEQUEUE_SAVE); -+ if (p_rq != rq) { -+ sched_info_dequeued(p_rq, p); -+ sched_info_queued(rq, p); -+ } -+ set_task_cpu(p, cpu); -+} -+ -+/* -+ * Returns a descheduling task to the runqueue unless it is being -+ * deactivated. -+ */ -+static inline void return_task(struct task_struct *p, struct rq *rq, -+ int cpu, bool deactivate) -+{ -+ if (deactivate) -+ deactivate_task(p, rq); -+ else { -+#ifdef CONFIG_SMP -+ /* -+ * set_task_cpu was called on the running task that doesn't -+ * want to deactivate so it has to be enqueued to a different -+ * CPU and we need its lock. Tag it to be moved with as the -+ * lock is dropped in finish_lock_switch. -+ */ -+ if (unlikely(p->wake_cpu != cpu)) -+ p->on_rq = TASK_ON_RQ_MIGRATING; -+ else -+#endif -+ enqueue_task(rq, p, ENQUEUE_RESTORE); -+ } -+} -+ -+/* Enter with rq lock held. We know p is on the local cpu */ -+static inline void __set_tsk_resched(struct task_struct *p) -+{ -+ set_tsk_need_resched(p); -+ set_preempt_need_resched(); -+} -+ -+/** -+ * task_curr - is this task currently executing on a CPU? -+ * @p: the task in question. -+ * -+ * Return: 1 if the task is currently executing. 0 otherwise. -+ */ -+inline int task_curr(const struct task_struct *p) -+{ -+ return cpu_curr(task_cpu(p)) == p; -+} -+ -+#ifdef CONFIG_SMP -+/* -+ * 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) -+{ -+ int running, queued; -+ unsigned long flags; -+ unsigned long ncsw; -+ struct rq *rq; -+ -+ for (;;) { -+ rq = task_rq(p); -+ -+ /* -+ * 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(rq, p)) { -+ if (match_state && unlikely(p->state != match_state)) -+ return 0; -+ cpu_relax(); -+ } -+ -+ /* -+ * Ok, time to look more closely! We need the rq -+ * lock now, to be *sure*. If we're wrong, we'll -+ * just go back and repeat. -+ */ -+ rq = task_rq_lock(p, &flags); -+ trace_sched_wait_task(p); -+ running = task_running(rq, p); -+ queued = task_on_rq_queued(p); -+ ncsw = 0; -+ if (!match_state || p->state == match_state) -+ ncsw = p->nvcsw | LONG_MIN; /* sets MSB */ -+ task_rq_unlock(rq, p, &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(queued)) { -+ ktime_t to = 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_sched_reschedule(cpu); -+ preempt_enable(); -+} -+EXPORT_SYMBOL_GPL(kick_process); -+#endif -+ -+/* -+ * 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; -+ if (p->policy == SCHED_BATCH) -+ return false; -+ /* SCHED_NORMAL and ISO will preempt based on deadline */ -+ if (!deadline_before(p->deadline, deadline)) -+ return false; -+ return true; -+} -+ -+#ifdef CONFIG_SMP -+ -+static inline bool is_per_cpu_kthread(struct task_struct *p) -+{ -+ if (!(p->flags & PF_KTHREAD)) -+ return false; -+ -+ if (p->nr_cpus_allowed != 1) -+ return false; -+ -+ return true; -+} -+ -+/* -+ * Per-CPU kthreads are allowed to run on !active && online CPUs, see -+ * __set_cpus_allowed_ptr(). -+ */ -+static inline bool is_cpu_allowed(struct task_struct *p, int cpu) -+{ -+ if (!cpumask_test_cpu(cpu, &p->cpus_allowed)) -+ return false; -+ -+ if (is_per_cpu_kthread(p)) -+ return cpu_online(cpu); -+ -+ return cpu_active(cpu); -+} -+ -+/* -+ * Check to see if p can run on cpu, and if not, whether there are any online -+ * CPUs it can run on instead. This only happens with the hotplug threads that -+ * bring up the CPUs. -+ */ -+static inline bool sched_other_cpu(struct task_struct *p, int cpu) -+{ -+ if (likely(cpumask_test_cpu(cpu, &p->cpus_allowed))) -+ return false; -+ if (p->nr_cpus_allowed == 1) { -+ cpumask_t valid_mask; -+ -+ cpumask_and(&valid_mask, &p->cpus_allowed, cpu_online_mask); -+ if (unlikely(cpumask_empty(&valid_mask))) -+ return false; -+ } -+ return true; -+} -+ -+static inline bool needs_other_cpu(struct task_struct *p, int cpu) -+{ -+ if (cpumask_test_cpu(cpu, &p->cpus_allowed)) -+ return false; -+ return true; -+} -+ -+#define cpu_online_map (*(cpumask_t *)cpu_online_mask) -+ -+static void try_preempt(struct task_struct *p, struct rq *this_rq) -+{ -+ int i, this_entries = rq_load(this_rq); -+ cpumask_t tmp; -+ -+ if (suitable_idle_cpus(p) && resched_best_idle(p, task_cpu(p))) -+ return; -+ -+ /* IDLEPRIO tasks never preempt anything but idle */ -+ if (p->policy == SCHED_IDLEPRIO) -+ return; -+ -+ cpumask_and(&tmp, &cpu_online_map, &p->cpus_allowed); -+ -+ for (i = 0; i < num_possible_cpus(); i++) { -+ struct rq *rq = this_rq->cpu_order[i]; -+ -+ if (!cpumask_test_cpu(rq->cpu, &tmp)) -+ continue; -+ -+ if (!sched_interactive && rq != this_rq && rq_load(rq) <= this_entries) -+ continue; -+ if (smt_schedule(p, rq) && can_preempt(p, rq->rq_prio, rq->rq_deadline)) { -+ /* We set rq->preempting lockless, it's a hint only */ -+ rq->preempting = p; -+ resched_curr(rq); -+ return; -+ } -+ } -+} -+ -+static int __set_cpus_allowed_ptr(struct task_struct *p, -+ const struct cpumask *new_mask, bool check); -+#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_curr(uprq); -+} -+ -+static inline int __set_cpus_allowed_ptr(struct task_struct *p, -+ const struct cpumask *new_mask, bool check) -+{ -+ return set_cpus_allowed_ptr(p, new_mask); -+} -+#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 0x04 /* internal use, task got migrated */ -+ -+static void -+ttwu_stat(struct task_struct *p, int cpu, int wake_flags) -+{ -+ struct rq *rq; -+ -+ if (!schedstat_enabled()) -+ return; -+ -+ rq = this_rq(); -+ -+#ifdef CONFIG_SMP -+ if (cpu == rq->cpu) { -+ __schedstat_inc(rq->ttwu_local); -+ } else { -+ struct sched_domain *sd; -+ -+ rcu_read_lock(); -+ for_each_domain(rq->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); -+} -+ -+static inline void ttwu_activate(struct rq *rq, struct task_struct *p) -+{ -+ activate_task(p, rq); -+ -+ /* if a worker is waking up, notify the workqueue */ -+ if (p->flags & PF_WQ_WORKER) -+ wq_worker_waking_up(p, cpu_of(rq)); -+} -+ -+/* -+ * Mark the task runnable and perform wakeup-preemption. -+ */ -+static void ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) -+{ -+ /* -+ * 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 (wake_flags & WF_SYNC) -+ resched_suitable_idle(p); -+ else -+ try_preempt(p, rq); -+ p->state = TASK_RUNNING; -+ trace_sched_wakeup(p); -+} -+ -+static void -+ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags) -+{ -+ lockdep_assert_held(rq->lock); -+ -+#ifdef CONFIG_SMP -+ if (p->sched_contributes_to_load) -+ rq->nr_uninterruptible--; -+#endif -+ -+ ttwu_activate(rq, p); -+ ttwu_do_wakeup(rq, p, wake_flags); -+} -+ -+/* -+ * Called in case the task @p isn't fully descheduled from its runqueue, -+ * in this case we must do a remote wakeup. Its a 'light' wakeup though, -+ * since all we need to do is flip p->state to TASK_RUNNING, since -+ * the task is still ->on_rq. -+ */ -+static int ttwu_remote(struct task_struct *p, int wake_flags) -+{ -+ struct rq *rq; -+ int ret = 0; -+ -+ rq = __task_rq_lock(p); -+ if (likely(task_on_rq_queued(p))) { -+ ttwu_do_wakeup(rq, p, wake_flags); -+ ret = 1; -+ } -+ __task_rq_unlock(rq); -+ -+ return ret; -+} -+ -+#ifdef CONFIG_SMP -+void sched_ttwu_pending(void) -+{ -+ struct rq *rq = this_rq(); -+ struct llist_node *llist = llist_del_all(&rq->wake_list); -+ struct task_struct *p, *t; -+ unsigned long flags; -+ -+ if (!llist) -+ return; -+ -+ rq_lock_irqsave(rq, &flags); -+ -+ llist_for_each_entry_safe(p, t, llist, wake_entry) -+ ttwu_do_activate(rq, p, 0); -+ -+ rq_unlock_irqrestore(rq, &flags); -+} -+ -+void scheduler_ipi(void) -+{ -+ /* -+ * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting -+ * TIF_NEED_RESCHED remotely (for the first time) will also send -+ * this IPI. -+ */ -+ preempt_fold_need_resched(); -+ -+ if (llist_empty(&this_rq()->wake_list) && (!idle_cpu(smp_processor_id()) || need_resched())) -+ return; -+ -+ /* -+ * Not all reschedule IPI handlers call irq_enter/irq_exit, since -+ * traditionally all their work was done from the interrupt return -+ * path. Now that we actually do some work, we need to make sure -+ * we do call them. -+ * -+ * Some archs already do call them, luckily irq_enter/exit nest -+ * properly. -+ * -+ * Arguably we should visit all archs and update all handlers, -+ * however a fair share of IPIs are still resched only so this would -+ * somewhat pessimize the simple resched case. -+ */ -+ irq_enter(); -+ sched_ttwu_pending(); -+ irq_exit(); -+} -+ -+static void ttwu_queue_remote(struct task_struct *p, int cpu, int wake_flags) -+{ -+ struct rq *rq = cpu_rq(cpu); -+ -+ if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)) { -+ if (!set_nr_if_polling(rq->idle)) -+ smp_sched_reschedule(cpu); -+ else -+ trace_sched_wake_idle_without_ipi(cpu); -+ } -+} -+ -+void wake_up_if_idle(int cpu) -+{ -+ struct rq *rq = cpu_rq(cpu); -+ unsigned long flags; -+ -+ rcu_read_lock(); -+ -+ if (!is_idle_task(rcu_dereference(rq->curr))) -+ goto out; -+ -+ if (set_nr_if_polling(rq->idle)) { -+ trace_sched_wake_idle_without_ipi(cpu); -+ } else { -+ rq_lock_irqsave(rq, &flags); -+ if (likely(is_idle_task(rq->curr))) -+ smp_sched_reschedule(cpu); -+ /* Else cpu is not in idle, do nothing here */ -+ rq_unlock_irqrestore(rq, &flags); -+ } -+ -+out: -+ rcu_read_unlock(); -+} -+ -+static int valid_task_cpu(struct task_struct *p) -+{ -+ cpumask_t valid_mask; -+ -+ if (p->flags & PF_KTHREAD) -+ cpumask_and(&valid_mask, &p->cpus_allowed, cpu_all_mask); -+ else -+ cpumask_and(&valid_mask, &p->cpus_allowed, cpu_active_mask); -+ -+ if (unlikely(!cpumask_weight(&valid_mask))) { -+ /* We shouldn't be hitting this any more */ -+ printk(KERN_WARNING "SCHED: No cpumask for %s/%d weight %d\n", p->comm, -+ p->pid, cpumask_weight(&p->cpus_allowed)); -+ return cpumask_any(&p->cpus_allowed); -+ } -+ return cpumask_any(&valid_mask); -+} -+ -+/* -+ * For a task that's just being woken up we have a valuable balancing -+ * opportunity so choose the nearest cache most lightly loaded runqueue. -+ * Entered with rq locked and returns with the chosen runqueue locked. -+ */ -+static inline int select_best_cpu(struct task_struct *p) -+{ -+ unsigned int idlest = ~0U; -+ struct rq *rq = NULL; -+ int i; -+ -+ if (suitable_idle_cpus(p)) { -+ int cpu = task_cpu(p); -+ -+ if (unlikely(needs_other_cpu(p, cpu))) -+ cpu = valid_task_cpu(p); -+ rq = resched_best_idle(p, cpu); -+ if (likely(rq)) -+ return rq->cpu; -+ } -+ -+ for (i = 0; i < num_possible_cpus(); i++) { -+ struct rq *other_rq = task_rq(p)->cpu_order[i]; -+ int entries; -+ -+ if (!other_rq->online) -+ continue; -+ if (needs_other_cpu(p, other_rq->cpu)) -+ continue; -+ entries = rq_load(other_rq); -+ if (entries >= idlest) -+ continue; -+ idlest = entries; -+ rq = other_rq; -+ } -+ if (unlikely(!rq)) -+ return task_cpu(p); -+ return rq->cpu; -+} -+#else /* CONFIG_SMP */ -+static int valid_task_cpu(struct task_struct *p) -+{ -+ return 0; -+} -+ -+static inline int select_best_cpu(struct task_struct *p) -+{ -+ return 0; -+} -+ -+static struct rq *resched_best_idle(struct task_struct *p, int cpu) -+{ -+ return NULL; -+} -+#endif /* CONFIG_SMP */ -+ -+static void ttwu_queue(struct task_struct *p, int cpu, int wake_flags) -+{ -+ struct rq *rq = cpu_rq(cpu); -+ -+#if defined(CONFIG_SMP) -+ if (!cpus_share_cache(smp_processor_id(), cpu)) { -+ sched_clock_cpu(cpu); /* Sync clocks across CPUs */ -+ ttwu_queue_remote(p, cpu, wake_flags); -+ return; -+ } -+#endif -+ rq_lock(rq); -+ ttwu_do_activate(rq, p, wake_flags); -+ rq_unlock(rq); -+} -+ -+/*** -+ * 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. -+ * -+ * Return: %true if @p was woken up, %false if it was already running. -+ * or @state didn't match @p's state. -+ */ -+static int -+try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags) -+{ -+ unsigned long flags; -+ int cpu, success = 0; -+ -+ /* -+ * If we are going to wake up a thread waiting for CONDITION we -+ * need to ensure that CONDITION=1 done by the caller can not be -+ * reordered with p->state check below. This pairs with mb() in -+ * set_current_state() the waiting thread does. -+ */ -+ raw_spin_lock_irqsave(&p->pi_lock, flags); -+ smp_mb__after_spinlock(); -+ /* state is a volatile long, どうして、分からない */ -+ if (!((unsigned int)p->state & state)) -+ goto out; -+ -+ trace_sched_waking(p); -+ -+ /* We're going to change ->state: */ -+ success = 1; -+ cpu = task_cpu(p); -+ -+ /* -+ * Ensure we load p->on_rq _after_ p->state, otherwise it would -+ * be possible to, falsely, observe p->on_rq == 0 and get stuck -+ * in smp_cond_load_acquire() below. -+ * -+ * sched_ttwu_pending() try_to_wake_up() -+ * STORE p->on_rq = 1 LOAD p->state -+ * UNLOCK rq->lock -+ * -+ * __schedule() (switch to task 'p') -+ * LOCK rq->lock smp_rmb(); -+ * smp_mb__after_spinlock(); -+ * UNLOCK rq->lock -+ * -+ * [task p] -+ * STORE p->state = UNINTERRUPTIBLE LOAD p->on_rq -+ * -+ * Pairs with the LOCK+smp_mb__after_spinlock() on rq->lock in -+ * __schedule(). See the comment for smp_mb__after_spinlock(). -+ */ -+ smp_rmb(); -+ if (p->on_rq && ttwu_remote(p, wake_flags)) -+ goto stat; -+ -+#ifdef CONFIG_SMP -+ /* -+ * Ensure we load p->on_cpu _after_ p->on_rq, otherwise it would be -+ * possible to, falsely, observe p->on_cpu == 0. -+ * -+ * One must be running (->on_cpu == 1) in order to remove oneself -+ * from the runqueue. -+ * -+ * __schedule() (switch to task 'p') try_to_wake_up() -+ * STORE p->on_cpu = 1 LOAD p->on_rq -+ * UNLOCK rq->lock -+ * -+ * __schedule() (put 'p' to sleep) -+ * LOCK rq->lock smp_rmb(); -+ * smp_mb__after_spinlock(); -+ * STORE p->on_rq = 0 LOAD p->on_cpu -+ * -+ * Pairs with the LOCK+smp_mb__after_spinlock() on rq->lock in -+ * __schedule(). See the comment for smp_mb__after_spinlock(). -+ */ -+ smp_rmb(); -+ -+ /* -+ * If the owning (remote) CPU is still in the middle of schedule() with -+ * this task as prev, wait until its done referencing the task. -+ * -+ * Pairs with the smp_store_release() in finish_task(). -+ * -+ * This ensures that tasks getting woken will be fully ordered against -+ * their previous state and preserve Program Order. -+ */ -+ smp_cond_load_acquire(&p->on_cpu, !VAL); -+ -+ p->sched_contributes_to_load = !!task_contributes_to_load(p); -+ p->state = TASK_WAKING; -+ -+ if (p->in_iowait) { -+ delayacct_blkio_end(p); -+ atomic_dec(&task_rq(p)->nr_iowait); -+ } -+ -+ cpu = select_best_cpu(p); -+ if (task_cpu(p) != cpu) -+ set_task_cpu(p, cpu); -+ -+#else /* CONFIG_SMP */ -+ -+ if (p->in_iowait) { -+ delayacct_blkio_end(p); -+ atomic_dec(&task_rq(p)->nr_iowait); -+ } -+ -+#endif /* CONFIG_SMP */ -+ -+ ttwu_queue(p, cpu, wake_flags); -+stat: -+ ttwu_stat(p, cpu, wake_flags); -+out: -+ raw_spin_unlock_irqrestore(&p->pi_lock, flags); -+ -+ return success; -+} -+ -+/** -+ * try_to_wake_up_local - try to wake up a local task with rq 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 rq is locked and, @p is not the current task. -+ * rq stays locked over invocation. -+ */ -+static void try_to_wake_up_local(struct task_struct *p) -+{ -+ struct rq *rq = task_rq(p); -+ -+ if (WARN_ON_ONCE(rq != this_rq()) || -+ WARN_ON_ONCE(p == current)) -+ return; -+ -+ lockdep_assert_held(rq->lock); -+ -+ if (!raw_spin_trylock(&p->pi_lock)) { -+ /* -+ * This is OK, because current is on_cpu, which avoids it being -+ * picked for load-balance and preemption/IRQs are still -+ * disabled avoiding further scheduler activity on it and we've -+ * not yet picked a replacement task. -+ */ -+ rq_unlock(rq); -+ raw_spin_lock(&p->pi_lock); -+ rq_lock(rq); -+ } -+ -+ if (!(p->state & TASK_NORMAL)) -+ goto out; -+ -+ trace_sched_waking(p); -+ -+ if (!task_on_rq_queued(p)) { -+ if (p->in_iowait) { -+ delayacct_blkio_end(p); -+ atomic_dec(&rq->nr_iowait); -+ } -+ ttwu_activate(rq, p); -+ } -+ -+ ttwu_do_wakeup(rq, p, 0); -+ ttwu_stat(p, smp_processor_id(), 0); -+out: -+ raw_spin_unlock(&p->pi_lock); -+} -+ -+/** -+ * 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. -+ * -+ * Return: 1 if the process was woken up, 0 if it was already running. -+ * -+ * This function executes a full memory barrier before accessing the task state. -+ */ -+int wake_up_process(struct task_struct *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, struct rq *rq); -+ -+/* -+ * Perform scheduler related setup for a newly forked process p. -+ * p is forked by current. -+ */ -+int sched_fork(unsigned long __maybe_unused clone_flags, struct task_struct *p) -+{ -+ unsigned long flags; -+ -+#ifdef CONFIG_PREEMPT_NOTIFIERS -+ INIT_HLIST_HEAD(&p->preempt_notifiers); -+#endif -+ /* -+ * We mark the process as NEW here. 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. -+ */ -+ p->state = TASK_NEW; -+ -+ /* -+ * 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 MuQSS patching */ -+ p->on_cpu = -+ p->on_rq = -+ p->utime = -+ p->stime = -+ p->sched_time = -+ p->stime_ns = -+ p->utime_ns = 0; -+ skiplist_node_init(&p->node); -+ -+ /* -+ * 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; -+ } -+ -+ /* -+ * Silence PROVE_RCU. -+ */ -+ raw_spin_lock_irqsave(&p->pi_lock, flags); -+ set_task_cpu(p, smp_processor_id()); -+ raw_spin_unlock_irqrestore(&p->pi_lock, flags); -+ -+#ifdef CONFIG_SCHED_INFO -+ if (unlikely(sched_info_on())) -+ memset(&p->sched_info, 0, sizeof(p->sched_info)); -+#endif -+ init_task_preempt_count(p); -+ -+ return 0; -+} -+ -+#ifdef CONFIG_SCHEDSTATS -+ -+DEFINE_STATIC_KEY_FALSE(sched_schedstats); -+static bool __initdata __sched_schedstats = false; -+ -+static void set_schedstats(bool enabled) -+{ -+ if (enabled) -+ static_branch_enable(&sched_schedstats); -+ else -+ static_branch_disable(&sched_schedstats); -+} -+ -+void force_schedstat_enabled(void) -+{ -+ if (!schedstat_enabled()) { -+ pr_info("kernel profiling enabled schedstats, disable via kernel.sched_schedstats.\n"); -+ static_branch_enable(&sched_schedstats); -+ } -+} -+ -+static int __init setup_schedstats(char *str) -+{ -+ int ret = 0; -+ if (!str) -+ goto out; -+ -+ /* -+ * This code is called before jump labels have been set up, so we can't -+ * change the static branch directly just yet. Instead set a temporary -+ * variable so init_schedstats() can do it later. -+ */ -+ if (!strcmp(str, "enable")) { -+ __sched_schedstats = true; -+ ret = 1; -+ } else if (!strcmp(str, "disable")) { -+ __sched_schedstats = false; -+ ret = 1; -+ } -+out: -+ if (!ret) -+ pr_warn("Unable to parse schedstats=\n"); -+ -+ return ret; -+} -+__setup("schedstats=", setup_schedstats); -+ -+static void __init init_schedstats(void) -+{ -+ set_schedstats(__sched_schedstats); -+} -+ -+#ifdef CONFIG_PROC_SYSCTL -+int sysctl_schedstats(struct ctl_table *table, int write, -+ void __user *buffer, size_t *lenp, loff_t *ppos) -+{ -+ struct ctl_table t; -+ int err; -+ int state = static_branch_likely(&sched_schedstats); -+ -+ if (write && !capable(CAP_SYS_ADMIN)) -+ return -EPERM; -+ -+ t = *table; -+ t.data = &state; -+ err = proc_dointvec_minmax(&t, write, buffer, lenp, ppos); -+ if (err < 0) -+ return err; -+ if (write) -+ set_schedstats(state); -+ return err; -+} -+#endif /* CONFIG_PROC_SYSCTL */ -+#else /* !CONFIG_SCHEDSTATS */ -+static inline void init_schedstats(void) {} -+#endif /* CONFIG_SCHEDSTATS */ -+ -+static void update_cpu_clock_switch(struct rq *rq, struct task_struct *p); -+ -+static void account_task_cpu(struct rq *rq, struct task_struct *p) -+{ -+ update_clocks(rq); -+ /* This isn't really a context switch but accounting is the same */ -+ update_cpu_clock_switch(rq, p); -+ p->last_ran = rq->niffies; -+} -+ -+bool sched_smp_initialized __read_mostly; -+ -+static inline int hrexpiry_enabled(struct rq *rq) -+{ -+ if (unlikely(!cpu_active(cpu_of(rq)) || !sched_smp_initialized)) -+ return 0; -+ return hrtimer_is_hres_active(&rq->hrexpiry_timer); -+} -+ -+/* -+ * Use HR-timers to deliver accurate preemption points. -+ */ -+static inline void hrexpiry_clear(struct rq *rq) -+{ -+ if (!hrexpiry_enabled(rq)) -+ return; -+ if (hrtimer_active(&rq->hrexpiry_timer)) -+ hrtimer_cancel(&rq->hrexpiry_timer); -+} -+ -+/* -+ * High-resolution time_slice expiry. -+ * Runs from hardirq context with interrupts disabled. -+ */ -+static enum hrtimer_restart hrexpiry(struct hrtimer *timer) -+{ -+ struct rq *rq = container_of(timer, struct rq, hrexpiry_timer); -+ struct task_struct *p; -+ -+ /* This can happen during CPU hotplug / resume */ -+ if (unlikely(cpu_of(rq) != smp_processor_id())) -+ goto out; -+ -+ /* -+ * We're doing this without the runqueue lock but this should always -+ * be run on the local CPU. Time slice should run out in __schedule -+ * but we set it to zero here in case niffies is slightly less. -+ */ -+ p = rq->curr; -+ p->time_slice = 0; -+ __set_tsk_resched(p); -+out: -+ return HRTIMER_NORESTART; -+} -+ -+/* -+ * Called to set the hrexpiry timer state. -+ * -+ * called with irqs disabled from the local CPU only -+ */ -+static void hrexpiry_start(struct rq *rq, u64 delay) -+{ -+ if (!hrexpiry_enabled(rq)) -+ return; -+ -+ hrtimer_start(&rq->hrexpiry_timer, ns_to_ktime(delay), -+ HRTIMER_MODE_REL_PINNED); -+} -+ -+static void init_rq_hrexpiry(struct rq *rq) -+{ -+ hrtimer_init(&rq->hrexpiry_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); -+ rq->hrexpiry_timer.function = hrexpiry; -+} -+ -+static inline int rq_dither(struct rq *rq) -+{ -+ if (!hrexpiry_enabled(rq)) -+ return HALF_JIFFY_US; -+ return 0; -+} -+ -+/* -+ * 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, *rq_curr; -+ struct rq *rq, *new_rq; -+ unsigned long flags; -+ -+ parent = p->parent; -+ -+ raw_spin_lock_irqsave(&p->pi_lock, flags); -+ p->state = TASK_RUNNING; -+ /* Task_rq can't change yet on a new task */ -+ new_rq = rq = task_rq(p); -+ if (unlikely(needs_other_cpu(p, task_cpu(p)))) { -+ set_task_cpu(p, valid_task_cpu(p)); -+ new_rq = task_rq(p); -+ } -+ -+ double_rq_lock(rq, new_rq); -+ rq_curr = rq->curr; -+ -+ /* -+ * Make sure we do not leak PI boosting priority to the child. -+ */ -+ p->prio = rq_curr->normal_prio; -+ -+ trace_sched_wakeup_new(p); -+ -+ /* -+ * 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. rq->rq_deadline is only -+ * modified within schedule() so it is always equal to -+ * current->deadline. -+ */ -+ account_task_cpu(rq, rq_curr); -+ p->last_ran = rq_curr->last_ran; -+ if (likely(rq_curr->policy != SCHED_FIFO)) { -+ rq_curr->time_slice /= 2; -+ if (rq_curr->time_slice < RESCHED_US) { -+ /* -+ * 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. -+ */ -+ __set_tsk_resched(rq_curr); -+ time_slice_expired(p, new_rq); -+ if (suitable_idle_cpus(p)) -+ resched_best_idle(p, task_cpu(p)); -+ else if (unlikely(rq != new_rq)) -+ try_preempt(p, new_rq); -+ } else { -+ p->time_slice = rq_curr->time_slice; -+ if (rq_curr == parent && rq == new_rq && !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_resched(rq_curr); -+ } else { -+ /* -+ * Adjust the hrexpiry since rq_curr will keep -+ * running and its timeslice has been shortened. -+ */ -+ hrexpiry_start(rq, US_TO_NS(rq_curr->time_slice)); -+ try_preempt(p, new_rq); -+ } -+ } -+ } else { -+ time_slice_expired(p, new_rq); -+ try_preempt(p, new_rq); -+ } -+ activate_task(p, new_rq); -+ double_rq_unlock(rq, new_rq); -+ raw_spin_unlock_irqrestore(&p->pi_lock, flags); -+} -+ -+#ifdef CONFIG_PREEMPT_NOTIFIERS -+ -+static DEFINE_STATIC_KEY_FALSE(preempt_notifier_key); -+ -+void preempt_notifier_inc(void) -+{ -+ static_branch_inc(&preempt_notifier_key); -+} -+EXPORT_SYMBOL_GPL(preempt_notifier_inc); -+ -+void preempt_notifier_dec(void) -+{ -+ static_branch_dec(&preempt_notifier_key); -+} -+EXPORT_SYMBOL_GPL(preempt_notifier_dec); -+ -+/** -+ * preempt_notifier_register - tell me when current is being preempted & rescheduled -+ * @notifier: notifier struct to register -+ */ -+void preempt_notifier_register(struct preempt_notifier *notifier) -+{ -+ if (!static_branch_unlikely(&preempt_notifier_key)) -+ WARN(1, "registering preempt_notifier while notifiers disabled\n"); -+ -+ 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 *not* 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 __always_inline void fire_sched_in_preempt_notifiers(struct task_struct *curr) -+{ -+ if (static_branch_unlikely(&preempt_notifier_key)) -+ __fire_sched_in_preempt_notifiers(curr); -+} -+ -+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); -+} -+ -+static __always_inline void -+fire_sched_out_preempt_notifiers(struct task_struct *curr, -+ struct task_struct *next) -+{ -+ if (static_branch_unlikely(&preempt_notifier_key)) -+ __fire_sched_out_preempt_notifiers(curr, next); -+} -+ -+#else /* !CONFIG_PREEMPT_NOTIFIERS */ -+ -+static inline void fire_sched_in_preempt_notifiers(struct task_struct *curr) -+{ -+} -+ -+static inline void -+fire_sched_out_preempt_notifiers(struct task_struct *curr, -+ struct task_struct *next) -+{ -+} -+ -+#endif /* CONFIG_PREEMPT_NOTIFIERS */ -+ -+static inline void prepare_task(struct task_struct *next) -+{ -+ /* -+ * Claim the task as running, we do this before switching to it -+ * such that any running task will have this set. -+ */ -+ next->on_cpu = 1; -+} -+ -+static inline void finish_task(struct task_struct *prev) -+{ -+#ifdef CONFIG_SMP -+ /* -+ * After ->on_cpu is cleared, the task can be moved to a different CPU. -+ * We must ensure this doesn't happen until the switch is completely -+ * finished. -+ * -+ * In particular, the load of prev->state in finish_task_switch() must -+ * happen before this. -+ * -+ * Pairs with the smp_cond_load_acquire() in try_to_wake_up(). -+ */ -+ smp_store_release(&prev->on_cpu, 0); -+#endif -+} -+ -+static inline void -+prepare_lock_switch(struct rq *rq, struct task_struct *next) -+{ -+ /* -+ * 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: -+ */ -+ spin_release(&rq->lock.dep_map, 1, _THIS_IP_); -+#ifdef CONFIG_DEBUG_SPINLOCK -+ /* this is a valid case when another task releases the spinlock */ -+ rq->lock.owner = next; -+#endif -+} -+ -+static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) -+{ -+ /* -+ * 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(&rq->lock.dep_map, 0, 0, _THIS_IP_); -+ -+#ifdef CONFIG_SMP -+ /* -+ * If prev was marked as migrating to another CPU in return_task, drop -+ * the local runqueue lock but leave interrupts disabled and grab the -+ * remote lock we're migrating it to before enabling them. -+ */ -+ if (unlikely(task_on_rq_migrating(prev))) { -+ sched_info_dequeued(rq, prev); -+ /* -+ * We move the ownership of prev to the new cpu now. ttwu can't -+ * activate prev to the wrong cpu since it has to grab this -+ * runqueue in ttwu_remote. -+ */ -+#ifdef CONFIG_THREAD_INFO_IN_TASK -+ prev->cpu = prev->wake_cpu; -+#else -+ task_thread_info(prev)->cpu = prev->wake_cpu; -+#endif -+ raw_spin_unlock(rq->lock); -+ -+ raw_spin_lock(&prev->pi_lock); -+ rq = __task_rq_lock(prev); -+ /* Check that someone else hasn't already queued prev */ -+ if (likely(!task_queued(prev))) { -+ enqueue_task(rq, prev, 0); -+ prev->on_rq = TASK_ON_RQ_QUEUED; -+ /* Wake up the CPU if it's not already running */ -+ resched_if_idle(rq); -+ } -+ raw_spin_unlock(&prev->pi_lock); -+ } -+#endif -+ rq_unlock(rq); -+ -+ do_pending_softirq(rq, current); -+ -+ local_irq_enable(); -+} -+ -+#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 -+ -+/** -+ * 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) -+{ -+ kcov_prepare_switch(prev); -+ sched_info_switch(rq, prev, next); -+ perf_event_task_sched_out(prev, next); -+ rseq_preempt(prev); -+ fire_sched_out_preempt_notifiers(prev, next); -+ prepare_task(next); -+ prepare_arch_switch(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.) -+ * -+ * 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 we need to recalculate this_rq -+ * because prev may have moved to another CPU. -+ */ -+static void finish_task_switch(struct task_struct *prev) -+ __releases(rq->lock) -+{ -+ struct rq *rq = this_rq(); -+ struct mm_struct *mm = rq->prev_mm; -+ long prev_state; -+ -+ /* -+ * The previous task will have left us with a preempt_count of 2 -+ * because it left us after: -+ * -+ * schedule() -+ * preempt_disable(); // 1 -+ * __schedule() -+ * raw_spin_lock_irq(rq->lock) // 2 -+ * -+ * Also, see FORK_PREEMPT_COUNT. -+ */ -+ if (WARN_ONCE(preempt_count() != 2*PREEMPT_DISABLE_OFFSET, -+ "corrupted preempt_count: %s/%d/0x%x\n", -+ current->comm, current->pid, preempt_count())) -+ preempt_count_set(FORK_PREEMPT_COUNT); -+ -+ 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. -+ * -+ * We must observe prev->state before clearing prev->on_cpu (in -+ * finish_task), otherwise a concurrent wakeup can get prev -+ * running on another CPU and we could rave with its RUNNING -> DEAD -+ * transition, resulting in a double drop. -+ */ -+ prev_state = prev->state; -+ vtime_task_switch(prev); -+ perf_event_task_sched_in(prev, current); -+ finish_task(prev); -+ finish_lock_switch(rq, prev); -+ finish_arch_post_lock_switch(); -+ kcov_finish_switch(current); -+ -+ fire_sched_in_preempt_notifiers(current); -+ /* -+ * When switching through a kernel thread, the loop in -+ * membarrier_{private,global}_expedited() may have observed that -+ * kernel thread and not issued an IPI. It is therefore possible to -+ * schedule between user->kernel->user threads without passing though -+ * switch_mm(). Membarrier requires a barrier after storing to -+ * rq->curr, before returning to userspace, so provide them here: -+ * -+ * - a full memory barrier for {PRIVATE,GLOBAL}_EXPEDITED, implicitly -+ * provided by mmdrop(), -+ * - a sync_core for SYNC_CORE. -+ */ -+ if (mm) { -+ membarrier_mm_sync_core_before_usermode(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); -+ -+ /* Task is done with its stack. */ -+ put_task_stack(prev); -+ -+ put_task_struct(prev); -+ } -+} -+ -+/** -+ * schedule_tail - first thing a freshly forked thread must call. -+ * @prev: the thread we just switched away from. -+ */ -+asmlinkage __visible void schedule_tail(struct task_struct *prev) -+{ -+ /* -+ * New tasks start with FORK_PREEMPT_COUNT, see there and -+ * finish_task_switch() for details. -+ * -+ * finish_task_switch() will drop rq->lock() and lower preempt_count -+ * and the preempt_enable() will end up enabling preemption (on -+ * PREEMPT_COUNT kernels). -+ */ -+ -+ finish_task_switch(prev); -+ preempt_enable(); -+ -+ if (current->set_child_tid) -+ put_user(task_pid_vnr(current), current->set_child_tid); -+ -+ calculate_sigpending(); -+} -+ -+/* -+ * context_switch - switch to the new MM and the new thread's register state. -+ */ -+static __always_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 is non-NULL, we pass through switch_mm(). If mm is -+ * NULL, we will pass through mmdrop() in finish_task_switch(). -+ * Both of these contain the full memory barrier required by -+ * membarrier after storing to rq->curr, before returning to -+ * user-space. -+ */ -+ if (!mm) { -+ next->active_mm = oldmm; -+ mmgrab(oldmm); -+ enter_lazy_tlb(oldmm, next); -+ } else -+ switch_mm_irqs_off(oldmm, mm, next); -+ -+ if (!prev->mm) { -+ prev->active_mm = NULL; -+ rq->prev_mm = oldmm; -+ } -+ prepare_lock_switch(rq, next); -+ -+ /* Here we just switch the register state and the stack. */ -+ switch_to(prev, next, prev); -+ barrier(); -+ -+ finish_task_switch(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. -+ */ -+unsigned long nr_running(void) -+{ -+ unsigned long i, sum = 0; -+ -+ for_each_online_cpu(i) -+ sum += cpu_rq(i)->nr_running; -+ -+ return sum; -+} -+ -+static unsigned long nr_uninterruptible(void) -+{ -+ unsigned long i, sum = 0; -+ -+ for_each_online_cpu(i) -+ sum += cpu_rq(i)->nr_uninterruptible; -+ -+ return sum; -+} -+ -+/* -+ * Check if only the current task is running on the CPU. -+ * -+ * Caution: this function does not check that the caller has disabled -+ * preemption, thus the result might have a time-of-check-to-time-of-use -+ * race. The caller is responsible to use it correctly, for example: -+ * -+ * - from a non-preemptable section (of course) -+ * -+ * - from a thread that is bound to a single CPU -+ * -+ * - in a loop with very short iterations (e.g. a polling loop) -+ */ -+bool single_task_running(void) -+{ -+ struct rq *rq = cpu_rq(smp_processor_id()); -+ -+ if (rq_load(rq) == 1) -+ return true; -+ else -+ return false; -+} -+EXPORT_SYMBOL(single_task_running); -+ -+unsigned long long nr_context_switches(void) -+{ -+ int i; -+ unsigned long long sum = 0; -+ -+ for_each_possible_cpu(i) -+ sum += cpu_rq(i)->nr_switches; -+ -+ return sum; -+} -+ -+/* -+ * IO-wait accounting, and how its mostly bollocks (on SMP). -+ * -+ * The idea behind IO-wait account is to account the idle time that we could -+ * have spend running if it were not for IO. That is, if we were to improve the -+ * storage performance, we'd have a proportional reduction in IO-wait time. -+ * -+ * This all works nicely on UP, where, when a task blocks on IO, we account -+ * idle time as IO-wait, because if the storage were faster, it could've been -+ * running and we'd not be idle. -+ * -+ * This has been extended to SMP, by doing the same for each CPU. This however -+ * is broken. -+ * -+ * Imagine for instance the case where two tasks block on one CPU, only the one -+ * CPU will have IO-wait accounted, while the other has regular idle. Even -+ * though, if the storage were faster, both could've ran at the same time, -+ * utilising both CPUs. -+ * -+ * This means, that when looking globally, the current IO-wait accounting on -+ * SMP is a lower bound, by reason of under accounting. -+ * -+ * Worse, since the numbers are provided per CPU, they are sometimes -+ * interpreted per CPU, and that is nonsensical. A blocked task isn't strictly -+ * associated with any one particular CPU, it can wake to another CPU than it -+ * blocked on. This means the per CPU IO-wait number is meaningless. -+ * -+ * Task CPU affinities can make all that even more 'interesting'. -+ */ -+ -+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; -+} -+ -+/* -+ * Consumers of these two interfaces, like for example the cpufreq menu -+ * governor are using nonsensical data. Boosting frequency for a CPU that has -+ * IO-wait which might not even end up running the task when it does become -+ * runnable. -+ */ -+ -+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(); -+} -+ -+/* -+ * I/O wait is the number of running or queued tasks with their ->rq pointer -+ * set to this cpu as being the CPU they're more likely to run on. -+ */ -+void get_iowait_load(unsigned long *nr_waiters, unsigned long *load) -+{ -+ struct rq *rq = this_rq(); -+ -+ *nr_waiters = atomic_read(&rq->nr_iowait); -+ *load = rq_load(rq); -+} -+ -+/* 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) -+{ -+ unsigned long newload; -+ -+ newload = load * exp + active * (FIXED_1 - exp); -+ if (active >= load) -+ newload += FIXED_1-1; -+ -+ return newload / FIXED_1; -+} -+ -+/* -+ * calc_load - update the avenrun load estimates every LOAD_FREQ seconds. -+ */ -+void calc_global_load(unsigned long ticks) -+{ -+ long active; -+ -+ if (time_before(jiffies, READ_ONCE(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_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 -+ -+#ifndef nsecs_to_cputime -+# define nsecs_to_cputime(__nsecs) nsecs_to_jiffies(__nsecs) -+#endif -+ -+/* -+ * On each tick, add the number of nanoseconds to the unbanked variables and -+ * once one tick's worth has accumulated, account it allowing for accurate -+ * sub-tick accounting and totals. Use the TICK_APPROX_NS to match the way we -+ * deduct nanoseconds. -+ */ -+static void pc_idle_time(struct rq *rq, struct task_struct *idle, unsigned long ns) -+{ -+ u64 *cpustat = kcpustat_this_cpu->cpustat; -+ unsigned long ticks; -+ -+ if (atomic_read(&rq->nr_iowait) > 0) { -+ rq->iowait_ns += ns; -+ if (rq->iowait_ns >= JIFFY_NS) { -+ ticks = NS_TO_JIFFIES(rq->iowait_ns); -+ cpustat[CPUTIME_IOWAIT] += (__force u64)TICK_APPROX_NS * ticks; -+ rq->iowait_ns %= JIFFY_NS; -+ } -+ } else { -+ rq->idle_ns += ns; -+ if (rq->idle_ns >= JIFFY_NS) { -+ ticks = NS_TO_JIFFIES(rq->idle_ns); -+ cpustat[CPUTIME_IDLE] += (__force u64)TICK_APPROX_NS * ticks; -+ rq->idle_ns %= JIFFY_NS; -+ } -+ } -+ acct_update_integrals(idle); -+} -+ -+static void pc_system_time(struct rq *rq, struct task_struct *p, -+ int hardirq_offset, unsigned long ns) -+{ -+ u64 *cpustat = kcpustat_this_cpu->cpustat; -+ unsigned long ticks; -+ -+ p->stime_ns += ns; -+ if (p->stime_ns >= JIFFY_NS) { -+ ticks = NS_TO_JIFFIES(p->stime_ns); -+ p->stime_ns %= JIFFY_NS; -+ p->stime += (__force u64)TICK_APPROX_NS * ticks; -+ account_group_system_time(p, TICK_APPROX_NS * ticks); -+ } -+ p->sched_time += ns; -+ account_group_exec_runtime(p, ns); -+ -+ if (hardirq_count() - hardirq_offset) { -+ rq->irq_ns += ns; -+ if (rq->irq_ns >= JIFFY_NS) { -+ ticks = NS_TO_JIFFIES(rq->irq_ns); -+ cpustat[CPUTIME_IRQ] += (__force u64)TICK_APPROX_NS * ticks; -+ rq->irq_ns %= JIFFY_NS; -+ } -+ } else if (in_serving_softirq()) { -+ rq->softirq_ns += ns; -+ if (rq->softirq_ns >= JIFFY_NS) { -+ ticks = NS_TO_JIFFIES(rq->softirq_ns); -+ cpustat[CPUTIME_SOFTIRQ] += (__force u64)TICK_APPROX_NS * ticks; -+ rq->softirq_ns %= JIFFY_NS; -+ } -+ } else { -+ rq->system_ns += ns; -+ if (rq->system_ns >= JIFFY_NS) { -+ ticks = NS_TO_JIFFIES(rq->system_ns); -+ cpustat[CPUTIME_SYSTEM] += (__force u64)TICK_APPROX_NS * ticks; -+ rq->system_ns %= JIFFY_NS; -+ } -+ } -+ acct_update_integrals(p); -+} -+ -+static void pc_user_time(struct rq *rq, struct task_struct *p, unsigned long ns) -+{ -+ u64 *cpustat = kcpustat_this_cpu->cpustat; -+ unsigned long ticks; -+ -+ p->utime_ns += ns; -+ if (p->utime_ns >= JIFFY_NS) { -+ ticks = NS_TO_JIFFIES(p->utime_ns); -+ p->utime_ns %= JIFFY_NS; -+ p->utime += (__force u64)TICK_APPROX_NS * ticks; -+ account_group_user_time(p, TICK_APPROX_NS * ticks); -+ } -+ p->sched_time += ns; -+ 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_ns += ns; -+ if (rq->softirq_ns >= JIFFY_NS) { -+ ticks = NS_TO_JIFFIES(rq->softirq_ns); -+ cpustat[CPUTIME_SOFTIRQ] += (__force u64)TICK_APPROX_NS * ticks; -+ rq->softirq_ns %= JIFFY_NS; -+ } -+ } -+ -+ if (task_nice(p) > 0 || idleprio_task(p)) { -+ rq->nice_ns += ns; -+ if (rq->nice_ns >= JIFFY_NS) { -+ ticks = NS_TO_JIFFIES(rq->nice_ns); -+ cpustat[CPUTIME_NICE] += (__force u64)TICK_APPROX_NS * ticks; -+ rq->nice_ns %= JIFFY_NS; -+ } -+ } else { -+ rq->user_ns += ns; -+ if (rq->user_ns >= JIFFY_NS) { -+ ticks = NS_TO_JIFFIES(rq->user_ns); -+ cpustat[CPUTIME_USER] += (__force u64)TICK_APPROX_NS * ticks; -+ rq->user_ns %= JIFFY_NS; -+ } -+ } -+ acct_update_integrals(p); -+} -+ -+/* -+ * 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) -+{ -+ s64 account_ns = rq->niffies - p->last_ran; -+ struct task_struct *idle = rq->idle; -+ -+ /* Accurate tick timekeeping */ -+ if (user_mode(get_irq_regs())) -+ pc_user_time(rq, p, account_ns); -+ else if (p != idle || (irq_count() != HARDIRQ_OFFSET)) { -+ pc_system_time(rq, p, HARDIRQ_OFFSET, account_ns); -+ } else -+ pc_idle_time(rq, idle, account_ns); -+ -+ /* time_slice accounting is done in usecs to avoid overflow on 32bit */ -+ if (p->policy != SCHED_FIFO && p != idle) -+ p->time_slice -= NS_TO_US(account_ns); -+ -+ p->last_ran = rq->niffies; -+} -+ -+/* -+ * 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) -+{ -+ s64 account_ns = rq->niffies - p->last_ran; -+ struct task_struct *idle = rq->idle; -+ -+ /* Accurate subtick timekeeping */ -+ if (p != idle) -+ pc_user_time(rq, p, account_ns); -+ else -+ pc_idle_time(rq, idle, account_ns); -+ -+ /* time_slice accounting is done in usecs to avoid overflow on 32bit */ -+ if (p->policy != SCHED_FIFO && p != idle) -+ p->time_slice -= NS_TO_US(account_ns); -+} -+ -+/* -+ * 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_rq_lock(p) held. -+ */ -+static inline u64 do_task_delta_exec(struct task_struct *p, struct rq *rq) -+{ -+ u64 ns = 0; -+ -+ /* -+ * Must be ->curr _and_ ->on_rq. If dequeued, we would -+ * project cycles that may never be accounted to this -+ * thread, breaking clock_gettime(). -+ */ -+ if (p == rq->curr && task_on_rq_queued(p)) { -+ update_clocks(rq); -+ ns = rq->niffies - p->last_ran; -+ } -+ -+ 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(struct task_struct *p) -+{ -+ unsigned long flags; -+ struct rq *rq; -+ u64 ns; -+ -+#if defined(CONFIG_64BIT) && defined(CONFIG_SMP) -+ /* -+ * 64-bit doesn't need locks to atomically read a 64-bit value. -+ * So we have a optimisation chance when the task's delta_exec is 0. -+ * Reading ->on_cpu is racy, but this is ok. -+ * -+ * If we race with it leaving CPU, we'll take a lock. So we're correct. -+ * If we race with it entering CPU, unaccounted time is 0. This is -+ * indistinguishable from the read occurring a few cycles earlier. -+ * If we see ->on_cpu without ->on_rq, the task is leaving, and has -+ * been accounted, so we're correct here as well. -+ */ -+ if (!p->on_cpu || !task_on_rq_queued(p)) -+ return tsk_seruntime(p); -+#endif -+ -+ rq = task_rq_lock(p, &flags); -+ ns = p->sched_time + do_task_delta_exec(p, rq); -+ task_rq_unlock(rq, p, &flags); -+ -+ return ns; -+} -+ -+/* -+ * Functions to test for when SCHED_ISO tasks have used their allocated -+ * quota as real time scheduling and convert them back to SCHED_NORMAL. All -+ * data is modified only by the local runqueue during scheduler_tick with -+ * interrupts disabled. -+ */ -+ -+/* -+ * 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 inline void iso_tick(struct rq *rq) -+{ -+ rq->iso_ticks = rq->iso_ticks * (ISO_PERIOD - 1) / ISO_PERIOD; -+ rq->iso_ticks += 100; -+ if (rq->iso_ticks > ISO_PERIOD * sched_iso_cpu) { -+ rq->iso_refractory = true; -+ if (unlikely(rq->iso_ticks > ISO_PERIOD * 100)) -+ rq->iso_ticks = ISO_PERIOD * 100; -+ } -+} -+ -+/* No SCHED_ISO task was running so decrease rq->iso_ticks */ -+static inline void no_iso_tick(struct rq *rq, int ticks) -+{ -+ if (rq->iso_ticks > 0 || rq->iso_refractory) { -+ rq->iso_ticks = rq->iso_ticks * (ISO_PERIOD - ticks) / ISO_PERIOD; -+ if (rq->iso_ticks < ISO_PERIOD * (sched_iso_cpu * 115 / 128)) { -+ rq->iso_refractory = false; -+ if (unlikely(rq->iso_ticks < 0)) -+ rq->iso_ticks = 0; -+ } -+ } -+} -+ -+/* 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 = rq->curr; -+ -+ /* -+ * 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_task(p) || task_running_iso(p)) -+ iso_tick(rq); -+ else -+ no_iso_tick(rq, 1); -+ -+ /* SCHED_FIFO tasks never run out of timeslice. */ -+ if (p->policy == SCHED_FIFO) -+ return; -+ -+ if (iso_task(p)) { -+ if (task_running_iso(p)) { -+ if (rq->iso_refractory) { -+ /* -+ * SCHED_ISO task is running as RT and limit -+ * has been hit. Force it to reschedule as -+ * SCHED_NORMAL by zeroing its time_slice -+ */ -+ p->time_slice = 0; -+ } -+ } else if (!rq->iso_refractory) { -+ /* Can now run again ISO. Reschedule to pick up prio */ -+ goto out_resched; -+ } -+ } -+ -+ /* -+ * 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. -+ * Dither is used as a backup for when hrexpiry is disabled or high res -+ * timers not configured in. -+ */ -+ if (p->time_slice - rq->dither >= RESCHED_US) -+ return; -+out_resched: -+ rq_lock(rq); -+ __set_tsk_resched(p); -+ rq_unlock(rq); -+} -+ -+static inline void task_tick(struct rq *rq) -+{ -+ if (!rq_idle(rq)) -+ task_running_tick(rq); -+ else if (rq->last_jiffy > rq->last_scheduler_tick) -+ no_iso_tick(rq, rq->last_jiffy - rq->last_scheduler_tick); -+} -+ -+#ifdef CONFIG_NO_HZ_FULL -+/* -+ * We can stop the timer tick any time highres timers are active since -+ * we rely entirely on highres timeouts for task expiry rescheduling. -+ */ -+static void sched_stop_tick(struct rq *rq, int cpu) -+{ -+ if (!hrexpiry_enabled(rq)) -+ return; -+ if (!tick_nohz_full_enabled()) -+ return; -+ if (!tick_nohz_full_cpu(cpu)) -+ return; -+ tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); -+} -+ -+static inline void sched_start_tick(struct rq *rq, int cpu) -+{ -+ tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); -+} -+ -+struct tick_work { -+ int cpu; -+ struct delayed_work work; -+}; -+ -+static struct tick_work __percpu *tick_work_cpu; -+ -+static void sched_tick_remote(struct work_struct *work) -+{ -+ struct delayed_work *dwork = to_delayed_work(work); -+ struct tick_work *twork = container_of(dwork, struct tick_work, work); -+ int cpu = twork->cpu; -+ struct rq *rq = cpu_rq(cpu); -+ struct task_struct *curr; -+ u64 delta; -+ -+ /* -+ * Handle the tick only if it appears the remote CPU is running in full -+ * dynticks mode. The check is racy by nature, but missing a tick or -+ * having one too much is no big deal because the scheduler tick updates -+ * statistics and checks timeslices in a time-independent way, regardless -+ * of when exactly it is running. -+ */ -+ if (idle_cpu(cpu) || !tick_nohz_tick_stopped_cpu(cpu)) -+ goto out_requeue; -+ -+ rq_lock_irq(rq); -+ curr = rq->curr; -+ if (is_idle_task(curr)) -+ goto out_unlock; -+ -+ update_rq_clock(rq); -+ delta = rq_clock_task(rq) - curr->last_ran; -+ -+ /* -+ * Make sure the next tick runs within a reasonable -+ * amount of time. -+ */ -+ WARN_ON_ONCE(delta > (u64)NSEC_PER_SEC * 3); -+ task_tick(rq); -+ -+out_unlock: -+ rq_unlock_irq(rq); -+ -+out_requeue: -+ /* -+ * Run the remote tick once per second (1Hz). This arbitrary -+ * frequency is large enough to avoid overload but short enough -+ * to keep scheduler internal stats reasonably up to date. -+ */ -+ queue_delayed_work(system_unbound_wq, dwork, HZ); -+} -+ -+static void sched_tick_start(int cpu) -+{ -+ struct tick_work *twork; -+ -+ if (housekeeping_cpu(cpu, HK_FLAG_TICK)) -+ return; -+ -+ WARN_ON_ONCE(!tick_work_cpu); -+ -+ twork = per_cpu_ptr(tick_work_cpu, cpu); -+ twork->cpu = cpu; -+ INIT_DELAYED_WORK(&twork->work, sched_tick_remote); -+ queue_delayed_work(system_unbound_wq, &twork->work, HZ); -+} -+ -+#ifdef CONFIG_HOTPLUG_CPU -+static void sched_tick_stop(int cpu) -+{ -+ struct tick_work *twork; -+ -+ if (housekeeping_cpu(cpu, HK_FLAG_TICK)) -+ return; -+ -+ WARN_ON_ONCE(!tick_work_cpu); -+ -+ twork = per_cpu_ptr(tick_work_cpu, cpu); -+ cancel_delayed_work_sync(&twork->work); -+} -+#endif /* CONFIG_HOTPLUG_CPU */ -+ -+int __init sched_tick_offload_init(void) -+{ -+ tick_work_cpu = alloc_percpu(struct tick_work); -+ BUG_ON(!tick_work_cpu); -+ -+ return 0; -+} -+ -+#else /* !CONFIG_NO_HZ_FULL */ -+static inline void sched_stop_tick(struct rq *rq, int cpu) {} -+static inline void sched_start_tick(struct rq *rq, int cpu) {} -+static inline void sched_tick_start(int cpu) { } -+static inline void sched_tick_stop(int cpu) { } -+#endif -+ -+/* -+ * This function gets called by the timer code, with HZ frequency. -+ * We call it with interrupts disabled. -+ */ -+void scheduler_tick(void) -+{ -+ int cpu __maybe_unused = smp_processor_id(); -+ struct rq *rq = cpu_rq(cpu); -+ -+ sched_clock_tick(); -+ update_clocks(rq); -+ update_load_avg(rq, 0); -+ update_cpu_clock_tick(rq, rq->curr); -+ task_tick(rq); -+ rq->last_scheduler_tick = rq->last_jiffy; -+ rq->last_tick = rq->clock; -+ perf_event_task_tick(); -+ sched_stop_tick(rq, cpu); -+} -+ -+#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \ -+ defined(CONFIG_TRACE_PREEMPT_TOGGLE)) -+/* -+ * If the value passed in is equal to the current preempt count -+ * then we just disabled preemption. Start timing the latency. -+ */ -+static inline void preempt_latency_start(int val) -+{ -+ if (preempt_count() == val) { -+ unsigned long ip = get_lock_parent_ip(); -+#ifdef CONFIG_DEBUG_PREEMPT -+ current->preempt_disable_ip = ip; -+#endif -+ trace_preempt_off(CALLER_ADDR0, ip); -+ } -+} -+ -+void preempt_count_add(int val) -+{ -+#ifdef CONFIG_DEBUG_PREEMPT -+ /* -+ * Underflow? -+ */ -+ if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0))) -+ return; -+#endif -+ __preempt_count_add(val); -+#ifdef CONFIG_DEBUG_PREEMPT -+ /* -+ * Spinlock count overflowing soon? -+ */ -+ DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >= -+ PREEMPT_MASK - 10); -+#endif -+ preempt_latency_start(val); -+} -+EXPORT_SYMBOL(preempt_count_add); -+NOKPROBE_SYMBOL(preempt_count_add); -+ -+/* -+ * If the value passed in equals to the current preempt count -+ * then we just enabled preemption. Stop timing the latency. -+ */ -+static inline void preempt_latency_stop(int val) -+{ -+ if (preempt_count() == val) -+ trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip()); -+} -+ -+void preempt_count_sub(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 -+ -+ preempt_latency_stop(val); -+ __preempt_count_sub(val); -+} -+EXPORT_SYMBOL(preempt_count_sub); -+NOKPROBE_SYMBOL(preempt_count_sub); -+ -+#else -+static inline void preempt_latency_start(int val) { } -+static inline void preempt_latency_stop(int val) { } -+#endif -+ -+static inline unsigned long get_preempt_disable_ip(struct task_struct *p) -+{ -+#ifdef CONFIG_DEBUG_PREEMPT -+ return p->preempt_disable_ip; -+#else -+ return 0; -+#endif -+} -+ -+/* -+ * The time_slice is only refilled when it is empty and that is when we set a -+ * new deadline. Make sure update_clocks has been called recently to update -+ * rq->niffies. -+ */ -+static void time_slice_expired(struct task_struct *p, struct rq *rq) -+{ -+ p->time_slice = timeslice(); -+ p->deadline = rq->niffies + task_deadline_diff(p); -+#ifdef CONFIG_SMT_NICE -+ if (!p->mm) -+ p->smt_bias = 0; -+ else if (rt_task(p)) -+ p->smt_bias = 1 << 30; -+ else if (task_running_iso(p)) -+ p->smt_bias = 1 << 29; -+ else if (idleprio_task(p)) { -+ if (task_running_idle(p)) -+ p->smt_bias = 0; -+ else -+ p->smt_bias = 1; -+ } else if (--p->smt_bias < 1) -+ p->smt_bias = MAX_PRIO - p->static_prio; -+#endif -+} -+ -+/* -+ * 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, struct rq *rq) -+{ -+ if (p->time_slice < RESCHED_US || batch_task(p)) -+ time_slice_expired(p, rq); -+} -+ -+/* -+ * Task selection with skiplists is a simple matter of picking off the first -+ * task in the sorted list, an O(1) operation. The lookup is amortised O(1) -+ * being bound to the number of processors. -+ * -+ * Runqueues are selectively locked based on their unlocked data and then -+ * unlocked if not needed. At most 3 locks will be held at any time and are -+ * released as soon as they're no longer needed. All balancing between CPUs -+ * is thus done here in an extremely simple first come best fit manner. -+ * -+ * This iterates over runqueues in cache locality order. In interactive mode -+ * it iterates over all CPUs and finds the task with the best key/deadline. -+ * In non-interactive mode it will only take a task if it's from the current -+ * runqueue or a runqueue with more tasks than the current one with a better -+ * key/deadline. -+ */ -+#ifdef CONFIG_SMP -+static inline struct task_struct -+*earliest_deadline_task(struct rq *rq, int cpu, struct task_struct *idle) -+{ -+ struct rq *locked = NULL, *chosen = NULL; -+ struct task_struct *edt = idle; -+ int i, best_entries = 0; -+ u64 best_key = ~0ULL; -+ -+ for (i = 0; i < total_runqueues; i++) { -+ struct rq *other_rq = rq_order(rq, i); -+ skiplist_node *next; -+ int entries; -+ -+ entries = other_rq->sl->entries; -+ /* -+ * Check for queued entres lockless first. The local runqueue -+ * is locked so entries will always be accurate. -+ */ -+ if (!sched_interactive) { -+ /* -+ * Don't reschedule balance across nodes unless the CPU -+ * is idle. -+ */ -+ if (edt != idle && rq->cpu_locality[other_rq->cpu] > 3) -+ break; -+ if (entries <= best_entries) -+ continue; -+ } else if (!entries) -+ continue; -+ -+ /* if (i) implies other_rq != rq */ -+ if (i) { -+ /* Check for best id queued lockless first */ -+ if (other_rq->best_key >= best_key) -+ continue; -+ -+ if (unlikely(!trylock_rq(rq, other_rq))) -+ continue; -+ -+ /* Need to reevaluate entries after locking */ -+ entries = other_rq->sl->entries; -+ if (unlikely(!entries)) { -+ unlock_rq(other_rq); -+ continue; -+ } -+ } -+ -+ next = other_rq->node; -+ /* -+ * In interactive mode we check beyond the best entry on other -+ * runqueues if we can't get the best for smt or affinity -+ * reasons. -+ */ -+ while ((next = next->next[0]) != other_rq->node) { -+ struct task_struct *p; -+ u64 key = next->key; -+ -+ /* Reevaluate key after locking */ -+ if (key >= best_key) -+ break; -+ -+ p = next->value; -+ if (!smt_schedule(p, rq)) { -+ if (i && !sched_interactive) -+ break; -+ continue; -+ } -+ -+ if (sched_other_cpu(p, cpu)) { -+ if (sched_interactive || !i) -+ continue; -+ break; -+ } -+ /* Make sure affinity is ok */ -+ if (i) { -+ /* From this point on p is the best so far */ -+ if (locked) -+ unlock_rq(locked); -+ chosen = locked = other_rq; -+ } -+ best_entries = entries; -+ best_key = key; -+ edt = p; -+ break; -+ } -+ /* rq->preempting is a hint only as the state may have changed -+ * since it was set with the resched call but if we have met -+ * the condition we can break out here. */ -+ if (edt == rq->preempting) -+ break; -+ if (i && other_rq != chosen) -+ unlock_rq(other_rq); -+ } -+ -+ if (likely(edt != idle)) -+ take_task(rq, cpu, edt); -+ -+ if (locked) -+ unlock_rq(locked); -+ -+ rq->preempting = NULL; -+ -+ return edt; -+} -+#else /* CONFIG_SMP */ -+static inline struct task_struct -+*earliest_deadline_task(struct rq *rq, int cpu, struct task_struct *idle) -+{ -+ struct task_struct *edt; -+ -+ if (unlikely(!rq->sl->entries)) -+ return idle; -+ edt = rq->node->next[0]->value; -+ take_task(rq, cpu, edt); -+ return edt; -+} -+#endif /* CONFIG_SMP */ -+ -+/* -+ * Print scheduling while atomic bug: -+ */ -+static noinline void __schedule_bug(struct task_struct *prev) -+{ -+ /* Save this before calling printk(), since that will clobber it */ -+ unsigned long preempt_disable_ip = get_preempt_disable_ip(current); -+ -+ 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); -+ if (IS_ENABLED(CONFIG_DEBUG_PREEMPT) -+ && in_atomic_preempt_off()) { -+ pr_err("Preemption disabled at:"); -+ print_ip_sym(preempt_disable_ip); -+ pr_cont("\n"); -+ } -+ 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) -+{ -+#ifdef CONFIG_SCHED_STACK_END_CHECK -+ if (task_stack_end_corrupted(prev)) -+ panic("corrupted stack end detected inside scheduler\n"); -+#endif -+ -+ if (unlikely(in_atomic_preempt_off())) { -+ __schedule_bug(prev); -+ preempt_count_set(PREEMPT_DISABLED); -+ } -+ 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. -+ */ -+static inline void set_rq_task(struct rq *rq, struct task_struct *p) -+{ -+ if (p == rq->idle || p->policy == SCHED_FIFO) -+ hrexpiry_clear(rq); -+ else -+ hrexpiry_start(rq, US_TO_NS(p->time_slice)); -+ if (rq->clock - rq->last_tick > HALF_JIFFY_NS) -+ rq->dither = 0; -+ else -+ rq->dither = rq_dither(rq); -+ -+ rq->rq_deadline = p->deadline; -+ rq->rq_prio = p->prio; -+#ifdef CONFIG_SMT_NICE -+ rq->rq_mm = p->mm; -+ rq->rq_smt_bias = p->smt_bias; -+#endif -+} -+ -+#ifdef CONFIG_SMT_NICE -+static void check_no_siblings(struct rq __maybe_unused *this_rq) {} -+static void wake_no_siblings(struct rq __maybe_unused *this_rq) {} -+static void (*check_siblings)(struct rq *this_rq) = &check_no_siblings; -+static void (*wake_siblings)(struct rq *this_rq) = &wake_no_siblings; -+ -+/* Iterate over smt siblings when we've scheduled a process on cpu and decide -+ * whether they should continue running or be descheduled. */ -+static void check_smt_siblings(struct rq *this_rq) -+{ -+ int other_cpu; -+ -+ for_each_cpu(other_cpu, &this_rq->thread_mask) { -+ struct task_struct *p; -+ struct rq *rq; -+ -+ rq = cpu_rq(other_cpu); -+ if (rq_idle(rq)) -+ continue; -+ p = rq->curr; -+ if (!smt_schedule(p, this_rq)) -+ resched_curr(rq); -+ } -+} -+ -+static void wake_smt_siblings(struct rq *this_rq) -+{ -+ int other_cpu; -+ -+ for_each_cpu(other_cpu, &this_rq->thread_mask) { -+ struct rq *rq; -+ -+ rq = cpu_rq(other_cpu); -+ if (rq_idle(rq)) -+ resched_idle(rq); -+ } -+} -+#else -+static void check_siblings(struct rq __maybe_unused *this_rq) {} -+static void wake_siblings(struct rq __maybe_unused *this_rq) {} -+#endif -+ -+/* -+ * 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 -+ * -+ * WARNING: must be called with preemption disabled! -+ */ -+static void __sched notrace __schedule(bool preempt) -+{ -+ struct task_struct *prev, *next, *idle; -+ unsigned long *switch_count; -+ bool deactivate = false; -+ struct rq *rq; -+ u64 niffies; -+ int cpu; -+ -+ cpu = smp_processor_id(); -+ rq = cpu_rq(cpu); -+ prev = rq->curr; -+ idle = rq->idle; -+ -+ schedule_debug(prev); -+ -+ local_irq_disable(); -+ rcu_note_context_switch(preempt); -+ -+ /* -+ * Make sure that signal_pending_state()->signal_pending() below -+ * can't be reordered with __set_current_state(TASK_INTERRUPTIBLE) -+ * done by the caller to avoid the race with signal_wake_up(). -+ * -+ * The membarrier system call requires a full memory barrier -+ * after coming from user-space, before storing to rq->curr. -+ */ -+ rq_lock(rq); -+ smp_mb__after_spinlock(); -+#ifdef CONFIG_SMP -+ if (rq->preempt) { -+ /* -+ * Make sure resched_curr hasn't triggered a preemption -+ * locklessly on a task that has since scheduled away. Spurious -+ * wakeup of idle is okay though. -+ */ -+ if (unlikely(preempt && prev != idle && !test_tsk_need_resched(prev))) { -+ rq->preempt = NULL; -+ clear_preempt_need_resched(); -+ rq_unlock_irq(rq); -+ return; -+ } -+ rq->preempt = NULL; -+ } -+#endif -+ -+ switch_count = &prev->nivcsw; -+ if (!preempt && prev->state) { -+ if (unlikely(signal_pending_state(prev->state, prev))) { -+ prev->state = TASK_RUNNING; -+ } else { -+ deactivate = true; -+ prev->on_rq = 0; -+ -+ if (prev->in_iowait) { -+ atomic_inc(&rq->nr_iowait); -+ delayacct_blkio_start(); -+ } -+ -+ /* -+ * 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); -+ if (to_wakeup) -+ try_to_wake_up_local(to_wakeup); -+ } -+ } -+ switch_count = &prev->nvcsw; -+ } -+ -+ /* -+ * Store the niffy value here for use by the next task's last_ran -+ * below to avoid losing niffies due to update_clocks being called -+ * again after this point. -+ */ -+ update_clocks(rq); -+ niffies = rq->niffies; -+ update_cpu_clock_switch(rq, prev); -+ -+ clear_tsk_need_resched(prev); -+ clear_preempt_need_resched(); -+ -+ if (idle != prev) { -+ check_deadline(prev, rq); -+ return_task(prev, rq, cpu, deactivate); -+ } -+ -+ next = earliest_deadline_task(rq, cpu, idle); -+ if (likely(next->prio != PRIO_LIMIT)) -+ clear_cpuidle_map(cpu); -+ else { -+ set_cpuidle_map(cpu); -+ update_load_avg(rq, 0); -+ } -+ -+ set_rq_task(rq, next); -+ next->last_ran = niffies; -+ -+ if (likely(prev != next)) { -+ /* -+ * Don't reschedule an idle task or deactivated tasks -+ */ -+ if (prev == idle) { -+ rq->nr_running++; -+ if (rt_task(next)) -+ rq->rt_nr_running++; -+ } else if (!deactivate) -+ resched_suitable_idle(prev); -+ if (unlikely(next == idle)) { -+ rq->nr_running--; -+ if (rt_task(prev)) -+ rq->rt_nr_running--; -+ wake_siblings(rq); -+ } else -+ check_siblings(rq); -+ rq->nr_switches++; -+ rq->curr = next; -+ /* -+ * The membarrier system call requires each architecture -+ * to have a full memory barrier after updating -+ * rq->curr, before returning to user-space. -+ * -+ * Here are the schemes providing that barrier on the -+ * various architectures: -+ * - mm ? switch_mm() : mmdrop() for x86, s390, sparc, PowerPC. -+ * switch_mm() rely on membarrier_arch_switch_mm() on PowerPC. -+ * - finish_lock_switch() for weakly-ordered -+ * architectures where spin_unlock is a full barrier, -+ * - switch_to() for arm64 (weakly-ordered, spin_unlock -+ * is a RELEASE barrier), -+ */ -+ ++*switch_count; -+ -+ trace_sched_switch(preempt, prev, next); -+ context_switch(rq, prev, next); /* unlocks the rq */ -+ } else { -+ check_siblings(rq); -+ rq_unlock(rq); -+ do_pending_softirq(rq, next); -+ local_irq_enable(); -+ } -+} -+ -+void __noreturn do_task_dead(void) -+{ -+ /* Causes final put_task_struct in finish_task_switch(). */ -+ set_special_state(TASK_DEAD); -+ -+ /* Tell freezer to ignore us: */ -+ current->flags |= PF_NOFREEZE; -+ __schedule(false); -+ BUG(); -+ -+ /* Avoid "noreturn function does return" - but don't continue if BUG() is a NOP: */ -+ for (;;) -+ cpu_relax(); -+} -+ -+static inline void sched_submit_work(struct task_struct *tsk) -+{ -+ if (!tsk->state || tsk_is_pi_blocked(tsk) || -+ preempt_count() || -+ signal_pending_state(tsk->state, tsk)) -+ return; -+ -+ /* -+ * If we are going to sleep and we have plugged IO queued, -+ * make sure to submit it to avoid deadlocks. -+ */ -+ if (blk_needs_flush_plug(tsk)) -+ blk_schedule_flush_plug(tsk); -+} -+ -+asmlinkage __visible void __sched schedule(void) -+{ -+ struct task_struct *tsk = current; -+ -+ sched_submit_work(tsk); -+ do { -+ preempt_disable(); -+ __schedule(false); -+ sched_preempt_enable_no_resched(); -+ } while (need_resched()); -+} -+ -+EXPORT_SYMBOL(schedule); -+ -+/* -+ * synchronize_rcu_tasks() makes sure that no task is stuck in preempted -+ * state (have scheduled out non-voluntarily) by making sure that all -+ * tasks have either left the run queue or have gone into user space. -+ * As idle tasks do not do either, they must not ever be preempted -+ * (schedule out non-voluntarily). -+ * -+ * schedule_idle() is similar to schedule_preempt_disable() except that it -+ * never enables preemption because it does not call sched_submit_work(). -+ */ -+void __sched schedule_idle(void) -+{ -+ /* -+ * As this skips calling sched_submit_work(), which the idle task does -+ * regardless because that function is a nop when the task is in a -+ * TASK_RUNNING state, make sure this isn't used someplace that the -+ * current task can be in any other state. Note, idle is always in the -+ * TASK_RUNNING state. -+ */ -+ WARN_ON_ONCE(current->state); -+ do { -+ __schedule(false); -+ } while (need_resched()); -+} -+ -+#ifdef CONFIG_CONTEXT_TRACKING -+asmlinkage __visible 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. -+ * -+ * NB: There are buggy callers of this function. Ideally we -+ * should warn if prev_state != IN_USER, but that will trigger -+ * too frequently to make sense yet. -+ */ -+ enum ctx_state prev_state = exception_enter(); -+ schedule(); -+ exception_exit(prev_state); -+} -+#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(); -+} -+ -+static void __sched notrace preempt_schedule_common(void) -+{ -+ do { -+ /* -+ * Because the function tracer can trace preempt_count_sub() -+ * and it also uses preempt_enable/disable_notrace(), if -+ * NEED_RESCHED is set, the preempt_enable_notrace() called -+ * by the function tracer will call this function again and -+ * cause infinite recursion. -+ * -+ * Preemption must be disabled here before the function -+ * tracer can trace. Break up preempt_disable() into two -+ * calls. One to disable preemption without fear of being -+ * traced. The other to still record the preemption latency, -+ * which can also be traced by the function tracer. -+ */ -+ preempt_disable_notrace(); -+ preempt_latency_start(1); -+ __schedule(true); -+ preempt_latency_stop(1); -+ preempt_enable_no_resched_notrace(); -+ -+ /* -+ * Check again in case we missed a preemption opportunity -+ * between schedule and now. -+ */ -+ } while (need_resched()); -+} -+ -+#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 __visible void __sched notrace preempt_schedule(void) -+{ -+ /* -+ * 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(!preemptible())) -+ return; -+ -+ preempt_schedule_common(); -+} -+NOKPROBE_SYMBOL(preempt_schedule); -+EXPORT_SYMBOL(preempt_schedule); -+ -+/** -+ * preempt_schedule_notrace - preempt_schedule called by tracing -+ * -+ * The tracing infrastructure uses preempt_enable_notrace to prevent -+ * recursion and tracing preempt enabling caused by the tracing -+ * infrastructure itself. But as tracing can happen in areas coming -+ * from userspace or just about to enter userspace, a preempt enable -+ * can occur before user_exit() is called. This will cause the scheduler -+ * to be called when the system is still in usermode. -+ * -+ * To prevent this, the preempt_enable_notrace will use this function -+ * instead of preempt_schedule() to exit user context if needed before -+ * calling the scheduler. -+ */ -+asmlinkage __visible void __sched notrace preempt_schedule_notrace(void) -+{ -+ enum ctx_state prev_ctx; -+ -+ if (likely(!preemptible())) -+ return; -+ -+ do { -+ /* -+ * Because the function tracer can trace preempt_count_sub() -+ * and it also uses preempt_enable/disable_notrace(), if -+ * NEED_RESCHED is set, the preempt_enable_notrace() called -+ * by the function tracer will call this function again and -+ * cause infinite recursion. -+ * -+ * Preemption must be disabled here before the function -+ * tracer can trace. Break up preempt_disable() into two -+ * calls. One to disable preemption without fear of being -+ * traced. The other to still record the preemption latency, -+ * which can also be traced by the function tracer. -+ */ -+ preempt_disable_notrace(); -+ preempt_latency_start(1); -+ /* -+ * Needs preempt disabled in case user_exit() is traced -+ * and the tracer calls preempt_enable_notrace() causing -+ * an infinite recursion. -+ */ -+ prev_ctx = exception_enter(); -+ __schedule(true); -+ exception_exit(prev_ctx); -+ -+ preempt_latency_stop(1); -+ preempt_enable_no_resched_notrace(); -+ } while (need_resched()); -+} -+EXPORT_SYMBOL_GPL(preempt_schedule_notrace); -+ -+#endif /* CONFIG_PREEMPT */ -+ -+/* -+ * 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 __visible void __sched preempt_schedule_irq(void) -+{ -+ enum ctx_state prev_state; -+ -+ /* Catch callers which need to be fixed */ -+ BUG_ON(preempt_count() || !irqs_disabled()); -+ -+ prev_state = exception_enter(); -+ -+ do { -+ preempt_disable(); -+ local_irq_enable(); -+ __schedule(true); -+ local_irq_disable(); -+ sched_preempt_enable_no_resched(); -+ } while (need_resched()); -+ -+ exception_exit(prev_state); -+} -+ -+int default_wake_function(wait_queue_entry_t *curr, unsigned mode, int wake_flags, -+ void *key) -+{ -+ return try_to_wake_up(curr->private, mode, wake_flags); -+} -+EXPORT_SYMBOL(default_wake_function); -+ -+#ifdef CONFIG_RT_MUTEXES -+ -+static inline int __rt_effective_prio(struct task_struct *pi_task, int prio) -+{ -+ if (pi_task) -+ prio = min(prio, pi_task->prio); -+ -+ return prio; -+} -+ -+static inline int rt_effective_prio(struct task_struct *p, int prio) -+{ -+ struct task_struct *pi_task = rt_mutex_get_top_task(p); -+ -+ return __rt_effective_prio(pi_task, prio); -+} -+ -+/* -+ * rt_mutex_setprio - set the current priority of a task -+ * @p: task to boost -+ * @pi_task: donor task -+ * -+ * 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. Call site only calls if the priority of the task changed. -+ */ -+void rt_mutex_setprio(struct task_struct *p, struct task_struct *pi_task) -+{ -+ int prio, oldprio; -+ struct rq *rq; -+ -+ /* XXX used to be waiter->prio, not waiter->task->prio */ -+ prio = __rt_effective_prio(pi_task, p->normal_prio); -+ -+ /* -+ * If nothing changed; bail early. -+ */ -+ if (p->pi_top_task == pi_task && prio == p->prio) -+ return; -+ -+ rq = __task_rq_lock(p); -+ update_rq_clock(rq); -+ /* -+ * Set under pi_lock && rq->lock, such that the value can be used under -+ * either lock. -+ * -+ * Note that there is loads of tricky to make this pointer cache work -+ * right. rt_mutex_slowunlock()+rt_mutex_postunlock() work together to -+ * ensure a task is de-boosted (pi_task is set to NULL) before the -+ * task is allowed to run again (and can exit). This ensures the pointer -+ * points to a blocked task -- which guaratees the task is present. -+ */ -+ p->pi_top_task = pi_task; -+ -+ /* -+ * For FIFO/RR we only need to set prio, if that matches we're done. -+ */ -+ if (prio == p->prio) -+ goto out_unlock; -+ -+ /* -+ * 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, pi_task); -+ oldprio = p->prio; -+ p->prio = prio; -+ if (task_running(rq, p)){ -+ if (prio > oldprio) -+ resched_task(p); -+ } else if (task_queued(p)) { -+ dequeue_task(rq, p, DEQUEUE_SAVE); -+ enqueue_task(rq, p, ENQUEUE_RESTORE); -+ if (prio < oldprio) -+ try_preempt(p, rq); -+ } -+out_unlock: -+ __task_rq_unlock(rq); -+} -+#else -+static inline int rt_effective_prio(struct task_struct *p, int prio) -+{ -+ return prio; -+} -+#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 new_static, old_static; -+ unsigned long flags; -+ struct rq *rq; -+ -+ if (task_nice(p) == nice || nice < MIN_NICE || nice > MAX_NICE) -+ 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 = task_rq_lock(p, &flags); -+ update_rq_clock(rq); -+ -+ /* -+ * 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; -+ } -+ -+ adjust_deadline(p, new_static); -+ old_static = p->static_prio; -+ p->static_prio = new_static; -+ p->prio = effective_prio(p); -+ -+ if (task_queued(p)) { -+ dequeue_task(rq, p, DEQUEUE_SAVE); -+ enqueue_task(rq, p, ENQUEUE_RESTORE); -+ if (new_static < old_static) -+ try_preempt(p, rq); -+ } else if (task_running(rq, p)) { -+ set_rq_task(rq, p); -+ if (old_static < new_static) -+ resched_task(p); -+ } -+out_unlock: -+ task_rq_unlock(rq, p, &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 = nice_to_rlimit(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. -+ */ -+ -+ increment = clamp(increment, -NICE_WIDTH, NICE_WIDTH); -+ nice = task_nice(current) + increment; -+ -+ nice = clamp_val(nice, MIN_NICE, MAX_NICE); -+ 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. -+ * -+ * Return: 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 - task_rq(p)->niffies); -+ if (unlikely(delta < 0)) -+ delta = 0; -+ delta = delta * 40 / ms_longest_deadline_diff(); -+ if (delta <= 80) -+ prio += delta; -+ if (idleprio_task(p)) -+ prio += 40; -+out: -+ return prio; -+} -+ -+/** -+ * idle_cpu - is a given CPU idle currently? -+ * @cpu: the processor in question. -+ * -+ * Return: 1 if the CPU is currently idle. 0 otherwise. -+ */ -+int idle_cpu(int cpu) -+{ -+ return cpu_curr(cpu) == cpu_rq(cpu)->idle; -+} -+ -+/** -+ * available_idle_cpu - is a given CPU idle for enqueuing work. -+ * @cpu: the CPU in question. -+ * -+ * Return: 1 if the CPU is currently idle. 0 otherwise. -+ */ -+int available_idle_cpu(int cpu) -+{ -+ if (!idle_cpu(cpu)) -+ return 0; -+ -+ if (vcpu_is_preempted(cpu)) -+ return 0; -+ -+ return 1; -+} -+ -+/** -+ * idle_task - return the idle task for a given CPU. -+ * @cpu: the processor in question. -+ * -+ * Return: The idle task for the CPU @cpu. -+ */ -+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. -+ * -+ * The task of @pid, if found. %NULL otherwise. -+ */ -+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 rq lock. */ -+static void __setscheduler(struct task_struct *p, struct rq *rq, int policy, -+ int prio, bool keep_boost) -+{ -+ int oldrtprio, oldprio; -+ -+ p->policy = policy; -+ oldrtprio = p->rt_priority; -+ p->rt_priority = prio; -+ p->normal_prio = normal_prio(p); -+ oldprio = p->prio; -+ /* -+ * Keep a potential priority boosting if called from -+ * sched_setscheduler(). -+ */ -+ p->prio = normal_prio(p); -+ if (keep_boost) -+ p->prio = rt_effective_prio(p, p->prio); -+ -+ if (task_running(rq, p)) { -+ set_rq_task(rq, p); -+ resched_task(p); -+ } else if (task_queued(p)) { -+ dequeue_task(rq, p, DEQUEUE_SAVE); -+ enqueue_task(rq, p, ENQUEUE_RESTORE); -+ if (p->prio < oldprio || p->rt_priority > oldrtprio) -+ try_preempt(p, rq); -+ } -+} -+ -+/* -+ * 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, -+ const struct sched_attr *attr, -+ bool user, bool pi) -+{ -+ int retval, policy = attr->sched_policy, oldpolicy = -1, priority = attr->sched_priority; -+ unsigned long flags, rlim_rtprio = 0; -+ int reset_on_fork; -+ struct rq *rq; -+ -+ /* The pi code expects interrupts enabled */ -+ BUG_ON(pi && 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; -+ priority = 0; -+ } -+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; -+ } -+ -+ if (attr->sched_flags & ~(SCHED_FLAG_ALL | SCHED_FLAG_SUGOV)) -+ 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 (priority < 0 || -+ (p->mm && priority > MAX_USER_RT_PRIO - 1) || -+ (!p->mm && priority > MAX_RT_PRIO - 1)) -+ return -EINVAL; -+ if (is_rt_policy(policy) != (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 (priority > p->rt_priority && -+ 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: -+ * -+ * To be able to change p->policy safely, the runqueue lock must be -+ * held. -+ */ -+ rq = task_rq_lock(p, &flags); -+ update_rq_clock(rq); -+ -+ /* -+ * Changing the policy of the stop threads its a very bad idea: -+ */ -+ if (p == rq->stop) { -+ task_rq_unlock(rq, p, &flags); -+ return -EINVAL; -+ } -+ -+ /* -+ * If not changing anything there's no need to proceed further: -+ */ -+ if (unlikely(policy == p->policy && (!is_rt_policy(policy) || -+ priority == p->rt_priority))) { -+ task_rq_unlock(rq, p, &flags); -+ return 0; -+ } -+ -+ /* Re-check policy now with rq lock held */ -+ if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) { -+ policy = oldpolicy = -1; -+ task_rq_unlock(rq, p, &flags); -+ goto recheck; -+ } -+ p->sched_reset_on_fork = reset_on_fork; -+ -+ __setscheduler(p, rq, policy, priority, pi); -+ task_rq_unlock(rq, p, &flags); -+ -+ if (pi) -+ rt_mutex_adjust_pi(p); -+out: -+ return 0; -+} -+ -+static int _sched_setscheduler(struct task_struct *p, int policy, -+ const struct sched_param *param, bool check) -+{ -+ struct sched_attr attr = { -+ .sched_policy = policy, -+ .sched_priority = param->sched_priority, -+ .sched_nice = PRIO_TO_NICE(p->static_prio), -+ }; -+ -+ return __sched_setscheduler(p, &attr, check, true); -+} -+/** -+ * 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. -+ * -+ * Return: 0 on success. An error code otherwise. -+ * -+ * 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); -+ -+int sched_setattr(struct task_struct *p, const struct sched_attr *attr) -+{ -+ return __sched_setscheduler(p, attr, true, true); -+} -+EXPORT_SYMBOL_GPL(sched_setattr); -+ -+int sched_setattr_nocheck(struct task_struct *p, const struct sched_attr *attr) -+{ -+ return __sched_setscheduler(p, attr, false, true); -+} -+ -+/** -+ * 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. -+ * -+ * Return: 0 on success. An error code otherwise. -+ */ -+int sched_setscheduler_nocheck(struct task_struct *p, int policy, -+ const struct sched_param *param) -+{ -+ return _sched_setscheduler(p, policy, param, false); -+} -+EXPORT_SYMBOL_GPL(sched_setscheduler_nocheck); -+ -+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; -+} -+ -+/* -+ * Mimics kernel/events/core.c perf_copy_attr(). -+ */ -+static int sched_copy_attr(struct sched_attr __user *uattr, -+ struct sched_attr *attr) -+{ -+ u32 size; -+ int ret; -+ -+ if (!access_ok(VERIFY_WRITE, uattr, SCHED_ATTR_SIZE_VER0)) -+ return -EFAULT; -+ -+ /* Zero the full structure, so that a short copy will be nice: */ -+ memset(attr, 0, sizeof(*attr)); -+ -+ ret = get_user(size, &uattr->size); -+ if (ret) -+ return ret; -+ -+ /* Bail out on silly large: */ -+ if (size > PAGE_SIZE) -+ goto err_size; -+ -+ /* ABI compatibility quirk: */ -+ if (!size) -+ size = SCHED_ATTR_SIZE_VER0; -+ -+ if (size < SCHED_ATTR_SIZE_VER0) -+ goto err_size; -+ -+ /* -+ * If we're handed a bigger struct than we know of, -+ * ensure all the unknown bits are 0 - i.e. new -+ * user-space does not rely on any kernel feature -+ * extensions we dont know about yet. -+ */ -+ if (size > sizeof(*attr)) { -+ unsigned char __user *addr; -+ unsigned char __user *end; -+ unsigned char val; -+ -+ addr = (void __user *)uattr + sizeof(*attr); -+ end = (void __user *)uattr + size; -+ -+ for (; addr < end; addr++) { -+ ret = get_user(val, addr); -+ if (ret) -+ return ret; -+ if (val) -+ goto err_size; -+ } -+ size = sizeof(*attr); -+ } -+ -+ ret = copy_from_user(attr, uattr, size); -+ if (ret) -+ return -EFAULT; -+ -+ /* -+ * XXX: Do we want to be lenient like existing syscalls; or do we want -+ * to be strict and return an error on out-of-bounds values? -+ */ -+ attr->sched_nice = clamp(attr->sched_nice, -20, 19); -+ -+ /* sched/core.c uses zero here but we already know ret is zero */ -+ return 0; -+ -+err_size: -+ put_user(sizeof(*attr), &uattr->size); -+ return -E2BIG; -+} -+ -+/* -+ * sched_setparam() passes in -1 for its policy, to let the functions -+ * it calls know not to change it. -+ */ -+#define SETPARAM_POLICY -1 -+ -+/** -+ * 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. -+ * -+ * Return: 0 on success. An error code otherwise. -+ */ -+SYSCALL_DEFINE3(sched_setscheduler, pid_t, pid, int, policy, struct sched_param __user *, param) -+{ -+ 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. -+ * -+ * Return: 0 on success. An error code otherwise. -+ */ -+SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param) -+{ -+ return do_sched_setscheduler(pid, SETPARAM_POLICY, param); -+} -+ -+/** -+ * sys_sched_setattr - same as above, but with extended sched_attr -+ * @pid: the pid in question. -+ * @uattr: structure containing the extended parameters. -+ */ -+SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr, -+ unsigned int, flags) -+{ -+ struct sched_attr attr; -+ struct task_struct *p; -+ int retval; -+ -+ if (!uattr || pid < 0 || flags) -+ return -EINVAL; -+ -+ retval = sched_copy_attr(uattr, &attr); -+ if (retval) -+ return retval; -+ -+ if ((int)attr.sched_policy < 0) -+ return -EINVAL; -+ -+ rcu_read_lock(); -+ retval = -ESRCH; -+ p = find_process_by_pid(pid); -+ if (p != NULL) -+ retval = sched_setattr(p, &attr); -+ rcu_read_unlock(); -+ -+ return retval; -+} -+ -+/** -+ * sys_sched_getscheduler - get the policy (scheduling class) of a thread -+ * @pid: the pid in question. -+ * -+ * Return: On success, the policy of the thread. Otherwise, a negative error -+ * code. -+ */ -+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. -+ * -+ * Return: On success, 0 and the RT priority is in @param. Otherwise, an error -+ * code. -+ */ -+SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param) -+{ -+ struct sched_param lp = { .sched_priority = 0 }; -+ 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; -+ -+ if (has_rt_policy(p)) -+ 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; -+} -+ -+static int sched_read_attr(struct sched_attr __user *uattr, -+ struct sched_attr *attr, -+ unsigned int usize) -+{ -+ int ret; -+ -+ if (!access_ok(VERIFY_WRITE, uattr, usize)) -+ return -EFAULT; -+ -+ /* -+ * If we're handed a smaller struct than we know of, -+ * ensure all the unknown bits are 0 - i.e. old -+ * user-space does not get uncomplete information. -+ */ -+ if (usize < sizeof(*attr)) { -+ unsigned char *addr; -+ unsigned char *end; -+ -+ addr = (void *)attr + usize; -+ end = (void *)attr + sizeof(*attr); -+ -+ for (; addr < end; addr++) { -+ if (*addr) -+ return -EFBIG; -+ } -+ -+ attr->size = usize; -+ } -+ -+ ret = copy_to_user(uattr, attr, attr->size); -+ if (ret) -+ return -EFAULT; -+ -+ /* sched/core.c uses zero here but we already know ret is zero */ -+ return ret; -+} -+ -+/** -+ * sys_sched_getattr - similar to sched_getparam, but with sched_attr -+ * @pid: the pid in question. -+ * @uattr: structure containing the extended parameters. -+ * @size: sizeof(attr) for fwd/bwd comp. -+ * @flags: for future extension. -+ */ -+SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr, -+ unsigned int, size, unsigned int, flags) -+{ -+ struct sched_attr attr = { -+ .size = sizeof(struct sched_attr), -+ }; -+ struct task_struct *p; -+ int retval; -+ -+ if (!uattr || pid < 0 || size > PAGE_SIZE || -+ size < SCHED_ATTR_SIZE_VER0 || flags) -+ return -EINVAL; -+ -+ 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; -+ -+ attr.sched_policy = p->policy; -+ if (rt_task(p)) -+ attr.sched_priority = p->rt_priority; -+ else -+ attr.sched_nice = task_nice(p); -+ -+ rcu_read_unlock(); -+ -+ retval = sched_read_attr(uattr, &attr, size); -+ 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; -+ -+ rcu_read_lock(); -+ -+ p = find_process_by_pid(pid); -+ if (!p) { -+ rcu_read_unlock(); -+ 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, true); -+ -+ 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); -+ return retval; -+} -+ -+static int get_user_cpu_mask(unsigned long __user *user_mask_ptr, unsigned len, -+ cpumask_t *new_mask) -+{ -+ if (len < cpumask_size()) -+ cpumask_clear(new_mask); -+ else if (len > cpumask_size()) -+ len = cpumask_size(); -+ -+ 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 -+ * -+ * Return: 0 on success. An error code otherwise. -+ */ -+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; -+ -+ raw_spin_lock_irqsave(&p->pi_lock, flags); -+ cpumask_and(mask, &p->cpus_allowed, cpu_active_mask); -+ raw_spin_unlock_irqrestore(&p->pi_lock, 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 -+ * -+ * Return: 0 on success. An error code otherwise. -+ */ -+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) { -+ unsigned int retlen = min(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. -+ * -+ * Return: 0. -+ */ -+static void do_sched_yield(void) -+{ -+ struct rq *rq; -+ -+ if (!sched_yield_type) -+ return; -+ -+ local_irq_disable(); -+ rq = this_rq(); -+ rq_lock(rq); -+ -+ if (sched_yield_type > 1) -+ time_slice_expired(current, rq); -+ schedstat_inc(rq->yld_count); -+ -+ /* -+ * Since we are going to call schedule() anyway, there's -+ * no need to preempt or enable interrupts: -+ */ -+ preempt_disable(); -+ rq_unlock(rq); -+ sched_preempt_enable_no_resched(); -+ -+ schedule(); -+} -+ -+SYSCALL_DEFINE0(sched_yield) -+{ -+ do_sched_yield(); -+ return 0; -+} -+ -+#ifndef CONFIG_PREEMPT -+int __sched _cond_resched(void) -+{ -+ if (should_resched(0)) { -+ preempt_schedule_common(); -+ return 1; -+ } -+ rcu_all_qs(); -+ return 0; -+} -+EXPORT_SYMBOL(_cond_resched); -+#endif -+ -+/* -+ * __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(PREEMPT_LOCK_OFFSET); -+ int ret = 0; -+ -+ lockdep_assert_held(lock); -+ -+ if (spin_needbreak(lock) || resched) { -+ spin_unlock(lock); -+ if (resched) -+ preempt_schedule_common(); -+ else -+ cpu_relax(); -+ ret = 1; -+ spin_lock(lock); -+ } -+ return ret; -+} -+EXPORT_SYMBOL(__cond_resched_lock); -+ -+/** -+ * 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); -+ do_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. -+ * -+ * Return: -+ * 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. -+ */ -+int __sched yield_to(struct task_struct *p, bool preempt) -+{ -+ struct task_struct *rq_p; -+ struct rq *rq, *p_rq; -+ unsigned long flags; -+ int yielded = 0; -+ -+ local_irq_save(flags); -+ rq = this_rq(); -+ -+again: -+ p_rq = task_rq(p); -+ /* -+ * If we're the only runnable task on the rq and target rq also -+ * has only one task, there's absolutely no point in yielding. -+ */ -+ if (task_running(p_rq, p) || p->state) { -+ yielded = -ESRCH; -+ goto out_irq; -+ } -+ -+ double_rq_lock(rq, p_rq); -+ if (unlikely(task_rq(p) != p_rq)) { -+ double_rq_unlock(rq, p_rq); -+ goto again; -+ } -+ -+ yielded = 1; -+ schedstat_inc(rq->yld_count); -+ rq_p = rq->curr; -+ if (p->deadline > rq_p->deadline) -+ p->deadline = rq_p->deadline; -+ p->time_slice += rq_p->time_slice; -+ if (p->time_slice > timeslice()) -+ p->time_slice = timeslice(); -+ time_slice_expired(rq_p, rq); -+ if (preempt && rq != p_rq) -+ resched_task(p_rq->curr); -+ double_rq_unlock(rq, p_rq); -+out_irq: -+ local_irq_restore(flags); -+ -+ if (yielded > 0) -+ schedule(); -+ return yielded; -+} -+EXPORT_SYMBOL_GPL(yield_to); -+ -+int io_schedule_prepare(void) -+{ -+ int old_iowait = current->in_iowait; -+ -+ current->in_iowait = 1; -+ blk_schedule_flush_plug(current); -+ -+ return old_iowait; -+} -+ -+void io_schedule_finish(int token) -+{ -+ current->in_iowait = token; -+} -+ -+/* -+ * 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) -+ */ -+ -+long __sched io_schedule_timeout(long timeout) -+{ -+ int token; -+ long ret; -+ -+ token = io_schedule_prepare(); -+ ret = schedule_timeout(timeout); -+ io_schedule_finish(token); -+ -+ return ret; -+} -+EXPORT_SYMBOL(io_schedule_timeout); -+ -+void io_schedule(void) -+{ -+ int token; -+ -+ token = io_schedule_prepare(); -+ schedule(); -+ io_schedule_finish(token); -+} -+EXPORT_SYMBOL(io_schedule); -+ -+/** -+ * sys_sched_get_priority_max - return maximum RT priority. -+ * @policy: scheduling class. -+ * -+ * Return: On success, this syscall returns the maximum -+ * rt_priority that can be used by a given scheduling class. -+ * On failure, a negative error code is returned. -+ */ -+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. -+ * -+ * Return: On success, this syscall returns the minimum -+ * rt_priority that can be used by a given scheduling class. -+ * On failure, a negative error code is returned. -+ */ -+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; -+} -+ -+static int sched_rr_get_interval(pid_t pid, struct timespec64 *t) -+{ -+ struct task_struct *p; -+ unsigned int time_slice; -+ unsigned long flags; -+ struct rq *rq; -+ int retval; -+ -+ 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; -+ -+ rq = task_rq_lock(p, &flags); -+ time_slice = p->policy == SCHED_FIFO ? 0 : MS_TO_NS(task_timeslice(p)); -+ task_rq_unlock(rq, p, &flags); -+ -+ rcu_read_unlock(); -+ *t = ns_to_timespec64(time_slice); -+ return 0; -+ -+out_unlock: -+ rcu_read_unlock(); -+ return retval; -+} -+ -+/** -+ * 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. -+ * -+ * Return: On success, 0 and the timeslice is in @interval. Otherwise, -+ * an error code. -+ */ -+SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid, -+ struct timespec __user *, interval) -+{ -+ struct timespec64 t; -+ int retval = sched_rr_get_interval(pid, &t); -+ -+ if (retval == 0) -+ retval = put_timespec64(&t, interval); -+ -+ return retval; -+} -+ -+#ifdef CONFIG_COMPAT -+COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval, -+ compat_pid_t, pid, -+ struct compat_timespec __user *, interval) -+{ -+ struct timespec64 t; -+ int retval = sched_rr_get_interval(pid, &t); -+ -+ if (retval == 0) -+ retval = compat_put_timespec64(&t, interval); -+ return retval; -+} -+#endif -+ -+void sched_show_task(struct task_struct *p) -+{ -+ unsigned long free = 0; -+ int ppid; -+ -+ if (!try_get_task_stack(p)) -+ return; -+ -+ printk(KERN_INFO "%-15.15s %c", p->comm, task_state_to_char(p)); -+ -+ if (p->state == TASK_RUNNING) -+ printk(KERN_CONT " running task "); -+#ifdef CONFIG_DEBUG_STACK_USAGE -+ free = stack_not_used(p); -+#endif -+ ppid = 0; -+ rcu_read_lock(); -+ if (pid_alive(p)) -+ 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); -+ put_task_stack(p); -+} -+EXPORT_SYMBOL_GPL(sched_show_task); -+ -+static inline bool -+state_filter_match(unsigned long state_filter, struct task_struct *p) -+{ -+ /* no filter, everything matches */ -+ if (!state_filter) -+ return true; -+ -+ /* filter, but doesn't match */ -+ if (!(p->state & state_filter)) -+ return false; -+ -+ /* -+ * When looking for TASK_UNINTERRUPTIBLE skip TASK_IDLE (allows -+ * TASK_KILLABLE). -+ */ -+ if (state_filter == TASK_UNINTERRUPTIBLE && p->state == TASK_IDLE) -+ return false; -+ -+ return true; -+} -+ -+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(); -+ for_each_process_thread(g, p) { -+ /* -+ * reset the NMI-timeout, listing all files on a slow -+ * console might take a lot of time: -+ * Also, reset softlockup watchdogs on all CPUs, because -+ * another CPU might be blocked waiting for us to process -+ * an IPI. -+ */ -+ touch_nmi_watchdog(); -+ touch_all_softlockup_watchdogs(); -+ if (state_filter_match(state_filter, p)) -+ sched_show_task(p); -+ } -+ -+ 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 set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask) -+{ -+ cpumask_copy(&p->cpus_allowed, new_mask); -+ p->nr_cpus_allowed = cpumask_weight(new_mask); -+} -+ -+void __do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) -+{ -+ struct rq *rq = task_rq(p); -+ -+ lockdep_assert_held(&p->pi_lock); -+ -+ cpumask_copy(&p->cpus_allowed, new_mask); -+ -+ if (task_queued(p)) { -+ /* -+ * Because __kthread_bind() calls this on blocked tasks without -+ * holding rq->lock. -+ */ -+ lockdep_assert_held(rq->lock); -+ } -+} -+ -+/* -+ * Calling do_set_cpus_allowed from outside the scheduler code should not be -+ * called on a running or queued task. We should be holding pi_lock. -+ */ -+void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) -+{ -+ __do_set_cpus_allowed(p, new_mask); -+ if (needs_other_cpu(p, task_cpu(p))) { -+ struct rq *rq; -+ -+ rq = __task_rq_lock(p); -+ set_task_cpu(p, valid_task_cpu(p)); -+ resched_task(p); -+ __task_rq_unlock(rq); -+ } -+} -+#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; -+ -+ raw_spin_lock_irqsave(&idle->pi_lock, flags); -+ raw_spin_lock(rq->lock); -+ idle->last_ran = rq->niffies; -+ time_slice_expired(idle, rq); -+ idle->state = TASK_RUNNING; -+ /* Setting prio to illegal value shouldn't matter when never queued */ -+ idle->prio = PRIO_LIMIT; -+ -+ kasan_unpoison_task_stack(idle); -+ -+#ifdef CONFIG_SMP -+ /* -+ * It's possible that init_idle() gets called multiple times on a task, -+ * in that case do_set_cpus_allowed() will not do the right thing. -+ * -+ * And since this is boot we can forgo the serialisation. -+ */ -+ set_cpus_allowed_common(idle, cpumask_of(cpu)); -+#ifdef CONFIG_SMT_NICE -+ idle->smt_bias = 0; -+#endif -+#endif -+ set_rq_task(rq, idle); -+ -+ /* Silence PROVE_RCU */ -+ rcu_read_lock(); -+ set_task_cpu(idle, cpu); -+ rcu_read_unlock(); -+ -+ rq->curr = rq->idle = idle; -+ idle->on_rq = TASK_ON_RQ_QUEUED; -+ raw_spin_unlock(rq->lock); -+ raw_spin_unlock_irqrestore(&idle->pi_lock, flags); -+ -+ /* Set the preempt count _outside_ the spinlocks! */ -+ init_idle_preempt_count(idle, cpu); -+ -+ ftrace_graph_init_idle_task(idle, cpu); -+ vtime_init_idle(idle, cpu); -+#ifdef CONFIG_SMP -+ sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu); -+#endif -+} -+ -+int cpuset_cpumask_can_shrink(const struct cpumask __maybe_unused *cur, -+ const struct cpumask __maybe_unused *trial) -+{ -+ return 1; -+} -+ -+int task_can_attach(struct task_struct *p, -+ const struct cpumask *cs_cpus_allowed) -+{ -+ int ret = 0; -+ -+ /* -+ * Kthreads which disallow setaffinity shouldn't be moved -+ * to a new cpuset; we don't want to change their CPU -+ * affinity and isolating such threads by their set of -+ * allowed nodes is unnecessary. Thus, cpusets are not -+ * applicable for such threads. This prevents checking for -+ * success of set_cpus_allowed_ptr() on all attached tasks -+ * before cpus_allowed may be changed. -+ */ -+ if (p->flags & PF_NO_SETAFFINITY) -+ ret = -EINVAL; -+ -+ return ret; -+} -+ -+void resched_cpu(int cpu) -+{ -+ struct rq *rq = cpu_rq(cpu); -+ unsigned long flags; -+ -+ rq_lock_irqsave(rq, &flags); -+ if (cpu_online(cpu) || cpu == smp_processor_id()) -+ resched_curr(rq); -+ rq_unlock_irqrestore(rq, &flags); -+} -+ -+#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) {} -+ -+/* -+ * 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 i, cpu = smp_processor_id(); -+ struct sched_domain *sd; -+ -+ if (!idle_cpu(cpu) && housekeeping_cpu(cpu, HK_FLAG_TIMER)) -+ return cpu; -+ -+ rcu_read_lock(); -+ for_each_domain(cpu, sd) { -+ for_each_cpu(i, sched_domain_span(sd)) { -+ if (cpu == i) -+ continue; -+ -+ if (!idle_cpu(i) && housekeeping_cpu(i, HK_FLAG_TIMER)) { -+ cpu = i; -+ cpu = i; -+ goto unlock; -+ } -+ } -+ } -+ -+ if (!housekeeping_cpu(cpu, HK_FLAG_TIMER)) -+ cpu = housekeeping_any_cpu(HK_FLAG_TIMER); -+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) -+{ -+ if (cpu == smp_processor_id()) -+ return; -+ -+ if (set_nr_and_not_polling(cpu_rq(cpu)->idle)) -+ smp_sched_reschedule(cpu); -+ else -+ trace_sched_wake_idle_without_ipi(cpu); -+} -+ -+static bool wake_up_full_nohz_cpu(int cpu) -+{ -+ /* -+ * We just need the target to call irq_exit() and re-evaluate -+ * the next tick. The nohz full kick at least implies that. -+ * If needed we can still optimize that later with an -+ * empty IRQ. -+ */ -+ if (cpu_is_offline(cpu)) -+ return true; /* Don't try to wake offline CPUs. */ -+ if (tick_nohz_full_cpu(cpu)) { -+ if (cpu != smp_processor_id() || -+ tick_nohz_tick_stopped()) -+ tick_nohz_full_kick_cpu(cpu); -+ return true; -+ } -+ -+ return false; -+} -+ -+/* -+ * Wake up the specified CPU. If the CPU is going offline, it is the -+ * caller's responsibility to deal with the lost wakeup, for example, -+ * by hooking into the CPU_DEAD notifier like timers and hrtimers do. -+ */ -+void wake_up_nohz_cpu(int cpu) -+{ -+ if (!wake_up_full_nohz_cpu(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. -+ */ -+static int __set_cpus_allowed_ptr(struct task_struct *p, -+ const struct cpumask *new_mask, bool check) -+{ -+ const struct cpumask *cpu_valid_mask = cpu_active_mask; -+ bool queued = false, running_wrong = false, kthread; -+ struct cpumask old_mask; -+ unsigned long flags; -+ int cpu, ret = 0; -+ struct rq *rq; -+ -+ rq = task_rq_lock(p, &flags); -+ update_rq_clock(rq); -+ -+ kthread = !!(p->flags & PF_KTHREAD); -+ if (kthread) { -+ /* -+ * Kernel threads are allowed on online && !active CPUs -+ */ -+ cpu_valid_mask = cpu_online_mask; -+ } -+ -+ /* -+ * Must re-check here, to close a race against __kthread_bind(), -+ * sched_setaffinity() is not guaranteed to observe the flag. -+ */ -+ if (check && (p->flags & PF_NO_SETAFFINITY)) { -+ ret = -EINVAL; -+ goto out; -+ } -+ -+ cpumask_copy(&old_mask, &p->cpus_allowed); -+ if (cpumask_equal(&old_mask, new_mask)) -+ goto out; -+ -+ if (!cpumask_intersects(new_mask, cpu_valid_mask)) { -+ ret = -EINVAL; -+ goto out; -+ } -+ -+ queued = task_queued(p); -+ __do_set_cpus_allowed(p, new_mask); -+ -+ if (kthread) { -+ /* -+ * For kernel threads that do indeed end up on online && -+ * !active we want to ensure they are strict per-CPU threads. -+ */ -+ WARN_ON(cpumask_intersects(new_mask, cpu_online_mask) && -+ !cpumask_intersects(new_mask, cpu_active_mask) && -+ p->nr_cpus_allowed != 1); -+ } -+ -+ /* 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(rq, p)) { -+ /* Task is running on the wrong cpu now, reschedule it. */ -+ if (rq == this_rq()) { -+ cpu = cpumask_any_and(cpu_valid_mask, new_mask); -+ set_task_cpu(p, cpu); -+ set_tsk_need_resched(p); -+ running_wrong = true; -+ } else -+ resched_task(p); -+ } else { -+ cpu = cpumask_any_and(cpu_valid_mask, new_mask); -+ if (queued) { -+ /* -+ * Switch runqueue locks after dequeueing the task -+ * here while still holding the pi_lock to be holding -+ * the correct lock for enqueueing. -+ */ -+ dequeue_task(rq, p, 0); -+ rq_unlock(rq); -+ -+ rq = cpu_rq(cpu); -+ rq_lock(rq); -+ } -+ set_task_cpu(p, cpu); -+ if (queued) -+ enqueue_task(rq, p, 0); -+ } -+ if (queued) -+ try_preempt(p, rq); -+ if (running_wrong) -+ preempt_disable(); -+out: -+ task_rq_unlock(rq, p, &flags); -+ -+ if (running_wrong) { -+ __schedule(true); -+ preempt_enable(); -+ } -+ -+ return ret; -+} -+ -+int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) -+{ -+ return __set_cpus_allowed_ptr(p, new_mask, false); -+} -+EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr); -+ -+#ifdef CONFIG_HOTPLUG_CPU -+/* -+ * Run through task list and find tasks affined to the dead cpu, then remove -+ * that cpu from the list, enable cpu0 and set the zerobound flag. Must hold -+ * cpu 0 and src_cpu's runqueue locks. -+ */ -+static void bind_zero(int src_cpu) -+{ -+ struct task_struct *p, *t; -+ struct rq *rq0; -+ int bound = 0; -+ -+ if (src_cpu == 0) -+ return; -+ -+ rq0 = cpu_rq(0); -+ -+ do_each_thread(t, p) { -+ if (cpumask_test_cpu(src_cpu, &p->cpus_allowed)) { -+ bool local = (task_cpu(p) == src_cpu); -+ struct rq *rq = task_rq(p); -+ -+ /* task_running is the cpu stopper thread */ -+ if (local && task_running(rq, p)) -+ continue; -+ atomic_clear_cpu(src_cpu, &p->cpus_allowed); -+ atomic_set_cpu(0, &p->cpus_allowed); -+ p->zerobound = true; -+ bound++; -+ if (local) { -+ bool queued = task_queued(p); -+ -+ if (queued) -+ dequeue_task(rq, p, 0); -+ set_task_cpu(p, 0); -+ if (queued) -+ enqueue_task(rq0, p, 0); -+ } -+ } -+ } while_each_thread(t, p); -+ -+ if (bound) { -+ printk(KERN_INFO "Removed affinity for %d processes to cpu %d\n", -+ bound, src_cpu); -+ } -+} -+ -+/* Find processes with the zerobound flag and reenable their affinity for the -+ * CPU coming alive. */ -+static void unbind_zero(int src_cpu) -+{ -+ int unbound = 0, zerobound = 0; -+ struct task_struct *p, *t; -+ -+ if (src_cpu == 0) -+ return; -+ -+ do_each_thread(t, p) { -+ if (!p->mm) -+ p->zerobound = false; -+ if (p->zerobound) { -+ unbound++; -+ cpumask_set_cpu(src_cpu, &p->cpus_allowed); -+ /* Once every CPU affinity has been re-enabled, remove -+ * the zerobound flag */ -+ if (cpumask_subset(cpu_possible_mask, &p->cpus_allowed)) { -+ p->zerobound = false; -+ zerobound++; -+ } -+ } -+ } while_each_thread(t, p); -+ -+ if (unbound) { -+ printk(KERN_INFO "Added affinity for %d processes to cpu %d\n", -+ unbound, src_cpu); -+ } -+ if (zerobound) { -+ printk(KERN_INFO "Released forced binding to cpu0 for %d processes\n", -+ zerobound); -+ } -+} -+ -+/* -+ * Ensure 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); -+ current->active_mm = &init_mm; -+ finish_arch_post_lock_switch(); -+ } -+ mmdrop(mm); -+} -+#else /* CONFIG_HOTPLUG_CPU */ -+static void unbind_zero(int src_cpu) {} -+#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; -+} -+ -+#define CPU_LOAD_IDX_MAX 5 -+static int min_load_idx = 0; -+static int max_load_idx = CPU_LOAD_IDX_MAX-1; -+ -+static void -+set_table_entry(struct ctl_table *entry, -+ const char *procname, void *data, int maxlen, -+ umode_t mode, proc_handler *proc_handler, -+ bool load_idx) -+{ -+ entry->procname = procname; -+ entry->data = data; -+ entry->maxlen = maxlen; -+ entry->mode = mode; -+ entry->proc_handler = proc_handler; -+ -+ if (load_idx) { -+ entry->extra1 = &min_load_idx; -+ entry->extra2 = &max_load_idx; -+ } -+} -+ -+static struct ctl_table * -+sd_alloc_ctl_domain_table(struct sched_domain *sd) -+{ -+ struct ctl_table *table = sd_alloc_ctl_entry(14); -+ -+ if (table == NULL) -+ return NULL; -+ -+ set_table_entry(&table[0], "min_interval", &sd->min_interval, -+ sizeof(long), 0644, proc_doulongvec_minmax, false); -+ set_table_entry(&table[1], "max_interval", &sd->max_interval, -+ sizeof(long), 0644, proc_doulongvec_minmax, false); -+ set_table_entry(&table[2], "busy_idx", &sd->busy_idx, -+ sizeof(int), 0644, proc_dointvec_minmax, true); -+ set_table_entry(&table[3], "idle_idx", &sd->idle_idx, -+ sizeof(int), 0644, proc_dointvec_minmax, true); -+ set_table_entry(&table[4], "newidle_idx", &sd->newidle_idx, -+ sizeof(int), 0644, proc_dointvec_minmax, true); -+ set_table_entry(&table[5], "wake_idx", &sd->wake_idx, -+ sizeof(int), 0644, proc_dointvec_minmax, true); -+ set_table_entry(&table[6], "forkexec_idx", &sd->forkexec_idx, -+ sizeof(int), 0644, proc_dointvec_minmax, true); -+ set_table_entry(&table[7], "busy_factor", &sd->busy_factor, -+ sizeof(int), 0644, proc_dointvec_minmax, false); -+ set_table_entry(&table[8], "imbalance_pct", &sd->imbalance_pct, -+ sizeof(int), 0644, proc_dointvec_minmax, false); -+ set_table_entry(&table[9], "cache_nice_tries", -+ &sd->cache_nice_tries, -+ sizeof(int), 0644, proc_dointvec_minmax, false); -+ set_table_entry(&table[10], "flags", &sd->flags, -+ sizeof(int), 0644, proc_dointvec_minmax, false); -+ set_table_entry(&table[11], "max_newidle_lb_cost", -+ &sd->max_newidle_lb_cost, -+ sizeof(long), 0644, proc_doulongvec_minmax, false); -+ set_table_entry(&table[12], "name", sd->name, -+ CORENAME_MAX_SIZE, 0444, proc_dostring, false); -+ /* &table[13] is terminator */ -+ -+ return table; -+} -+ -+static struct 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 cpumask_var_t sd_sysctl_cpus; -+static struct ctl_table_header *sd_sysctl_header; -+ -+void register_sched_domain_sysctl(void) -+{ -+ static struct ctl_table *cpu_entries; -+ static struct ctl_table **cpu_idx; -+ char buf[32]; -+ int i; -+ -+ if (!cpu_entries) { -+ cpu_entries = sd_alloc_ctl_entry(num_possible_cpus() + 1); -+ if (!cpu_entries) -+ return; -+ -+ WARN_ON(sd_ctl_dir[0].child); -+ sd_ctl_dir[0].child = cpu_entries; -+ } -+ -+ if (!cpu_idx) { -+ struct ctl_table *e = cpu_entries; -+ -+ cpu_idx = kcalloc(nr_cpu_ids, sizeof(struct ctl_table*), GFP_KERNEL); -+ if (!cpu_idx) -+ return; -+ -+ /* deal with sparse possible map */ -+ for_each_possible_cpu(i) { -+ cpu_idx[i] = e; -+ e++; -+ } -+ } -+ -+ if (!cpumask_available(sd_sysctl_cpus)) { -+ if (!alloc_cpumask_var(&sd_sysctl_cpus, GFP_KERNEL)) -+ return; -+ -+ /* init to possible to not have holes in @cpu_entries */ -+ cpumask_copy(sd_sysctl_cpus, cpu_possible_mask); -+ } -+ -+ for_each_cpu(i, sd_sysctl_cpus) { -+ struct ctl_table *e = cpu_idx[i]; -+ -+ if (e->child) -+ sd_free_ctl_entry(&e->child); -+ -+ if (!e->procname) { -+ snprintf(buf, 32, "cpu%d", i); -+ e->procname = kstrdup(buf, GFP_KERNEL); -+ } -+ e->mode = 0555; -+ e->child = sd_alloc_ctl_cpu_table(i); -+ -+ __cpumask_clear_cpu(i, sd_sysctl_cpus); -+ } -+ -+ WARN_ON(sd_sysctl_header); -+ sd_sysctl_header = register_sysctl_table(sd_ctl_root); -+} -+ -+void dirty_sched_domain_sysctl(int cpu) -+{ -+ if (cpumask_available(sd_sysctl_cpus)) -+ __cpumask_set_cpu(cpu, sd_sysctl_cpus); -+} -+ -+/* may be called multiple times per register */ -+void unregister_sched_domain_sysctl(void) -+{ -+ unregister_sysctl_table(sd_sysctl_header); -+ sd_sysctl_header = NULL; -+} -+#endif /* CONFIG_SYSCTL */ -+ -+void set_rq_online(struct rq *rq) -+{ -+ if (!rq->online) { -+ cpumask_set_cpu(cpu_of(rq), rq->rd->online); -+ rq->online = true; -+ } -+} -+ -+void set_rq_offline(struct rq *rq) -+{ -+ if (rq->online) { -+ int cpu = cpu_of(rq); -+ -+ cpumask_clear_cpu(cpu, rq->rd->online); -+ rq->online = false; -+ clear_cpuidle_map(cpu); -+ } -+} -+ -+/* -+ * used to mark begin/end of suspend/resume: -+ */ -+static int num_cpus_frozen; -+ -+/* -+ * Update cpusets according to cpu_active mask. If cpusets are -+ * disabled, cpuset_update_active_cpus() becomes a simple wrapper -+ * around partition_sched_domains(). -+ * -+ * If we come here as part of a suspend/resume, don't touch cpusets because we -+ * want to restore it back to its original state upon resume anyway. -+ */ -+static void cpuset_cpu_active(void) -+{ -+ if (cpuhp_tasks_frozen) { -+ /* -+ * num_cpus_frozen tracks how many CPUs are involved in suspend -+ * resume sequence. As long as this is not the last online -+ * operation in the resume sequence, just build a single sched -+ * domain, ignoring cpusets. -+ */ -+ partition_sched_domains(1, NULL, NULL); -+ if (--num_cpus_frozen) -+ return; -+ /* -+ * This is the last CPU online operation. So fall through and -+ * restore the original sched domains by considering the -+ * cpuset configurations. -+ */ -+ cpuset_force_rebuild(); -+ } -+ -+ cpuset_update_active_cpus(); -+} -+ -+static int cpuset_cpu_inactive(unsigned int cpu) -+{ -+ if (!cpuhp_tasks_frozen) { -+ cpuset_update_active_cpus(); -+ } else { -+ num_cpus_frozen++; -+ partition_sched_domains(1, NULL, NULL); -+ } -+ return 0; -+} -+ -+int sched_cpu_activate(unsigned int cpu) -+{ -+ struct rq *rq = cpu_rq(cpu); -+ unsigned long flags; -+ -+ set_cpu_active(cpu, true); -+ -+ if (sched_smp_initialized) { -+ sched_domains_numa_masks_set(cpu); -+ cpuset_cpu_active(); -+ } -+ -+ /* -+ * Put the rq online, if not already. This happens: -+ * -+ * 1) In the early boot process, because we build the real domains -+ * after all CPUs have been brought up. -+ * -+ * 2) At runtime, if cpuset_cpu_active() fails to rebuild the -+ * domains. -+ */ -+ rq_lock_irqsave(rq, &flags); -+ if (rq->rd) { -+ BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); -+ set_rq_online(rq); -+ } -+ unbind_zero(cpu); -+ rq_unlock_irqrestore(rq, &flags); -+ -+ return 0; -+} -+ -+int sched_cpu_deactivate(unsigned int cpu) -+{ -+ int ret; -+ -+ set_cpu_active(cpu, false); -+ /* -+ * We've cleared cpu_active_mask, wait for all preempt-disabled and RCU -+ * users of this state to go away such that all new such users will -+ * observe it. -+ * -+ * Do sync before park smpboot threads to take care the rcu boost case. -+ */ -+ synchronize_rcu_mult(call_rcu, call_rcu_sched); -+ -+ if (!sched_smp_initialized) -+ return 0; -+ -+ ret = cpuset_cpu_inactive(cpu); -+ if (ret) { -+ set_cpu_active(cpu, true); -+ return ret; -+ } -+ sched_domains_numa_masks_clear(cpu); -+ return 0; -+} -+ -+int sched_cpu_starting(unsigned int cpu) -+{ -+ sched_tick_start(cpu); -+ return 0; -+} -+ -+#ifdef CONFIG_HOTPLUG_CPU -+int sched_cpu_dying(unsigned int cpu) -+{ -+ struct rq *rq = cpu_rq(cpu); -+ unsigned long flags; -+ -+ /* Handle pending wakeups and then migrate everything off */ -+ sched_ttwu_pending(); -+ sched_tick_stop(cpu); -+ -+ local_irq_save(flags); -+ double_rq_lock(rq, cpu_rq(0)); -+ if (rq->rd) { -+ BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); -+ set_rq_offline(rq); -+ } -+ bind_zero(cpu); -+ double_rq_unlock(rq, cpu_rq(0)); -+ sched_start_tick(rq, cpu); -+ hrexpiry_clear(rq); -+ local_irq_restore(flags); -+ -+ return 0; -+} -+#endif -+ -+#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(struct rq *rq) -+{ -+ return rq_idle(rq); -+} -+#endif -+#ifdef CONFIG_SCHED_SMT -+static const cpumask_t *thread_cpumask(int cpu) -+{ -+ return topology_sibling_cpumask(cpu); -+} -+/* All this CPU's SMT siblings are idle */ -+static bool siblings_cpu_idle(struct rq *rq) -+{ -+ return cpumask_subset(&rq->thread_mask, &cpu_idle_map); -+} -+#endif -+#ifdef CONFIG_SCHED_MC -+static const cpumask_t *core_cpumask(int cpu) -+{ -+ return topology_core_cpumask(cpu); -+} -+/* All this CPU's shared cache siblings are idle */ -+static bool cache_cpu_idle(struct rq *rq) -+{ -+ return cpumask_subset(&rq->core_mask, &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 rq *rq, *other_rq, *leader; -+ struct sched_domain *sd; -+ int cpu, other_cpu, i; -+#ifdef CONFIG_SCHED_SMT -+ bool smt_threads = false; -+#endif -+ sched_init_numa(); -+ -+ /* -+ * There's no userspace yet to cause hotplug operations; hence all the -+ * cpu masks are stable and all blatant races in the below code cannot -+ * happen. -+ */ -+ mutex_lock(&sched_domains_mutex); -+ sched_init_domains(cpu_active_mask); -+ mutex_unlock(&sched_domains_mutex); -+ -+ /* Move init over to a non-isolated CPU */ -+ if (set_cpus_allowed_ptr(current, housekeeping_cpumask(HK_FLAG_DOMAIN)) < 0) -+ BUG(); -+ -+ mutex_lock(&sched_domains_mutex); -+ local_irq_disable(); -+ lock_all_rqs(); -+ /* -+ * 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) { -+ rq = cpu_rq(cpu); -+ -+ /* First check if this cpu is in the same node */ -+ for_each_domain(cpu, sd) { -+ if (sd->level > SD_LV_MC) -+ continue; -+ leader = NULL; -+ /* Set locality to local node if not already found lower */ -+ for_each_cpu(other_cpu, sched_domain_span(sd)) { -+ if (rqshare == RQSHARE_SMP) { -+ other_rq = cpu_rq(other_cpu); -+ -+ /* Set the smp_leader to the first CPU */ -+ if (!leader) -+ leader = rq; -+ other_rq->smp_leader = leader; -+ } -+ -+ if (rq->cpu_locality[other_cpu] > 3) -+ rq->cpu_locality[other_cpu] = 3; -+ } -+ } -+ -+ /* -+ * Each runqueue has its own function in case it doesn't have -+ * siblings of its own allowing mixed topologies. -+ */ -+#ifdef CONFIG_SCHED_MC -+ leader = NULL; -+ if (cpumask_weight(core_cpumask(cpu)) > 1) { -+ cpumask_copy(&rq->core_mask, core_cpumask(cpu)); -+ cpumask_clear_cpu(cpu, &rq->core_mask); -+ for_each_cpu(other_cpu, core_cpumask(cpu)) { -+ if (rqshare == RQSHARE_MC) { -+ other_rq = cpu_rq(other_cpu); -+ -+ /* Set the mc_leader to the first CPU */ -+ if (!leader) -+ leader = rq; -+ other_rq->mc_leader = leader; -+ } -+ if (rq->cpu_locality[other_cpu] > 2) -+ rq->cpu_locality[other_cpu] = 2; -+ } -+ rq->cache_idle = cache_cpu_idle; -+ } -+#endif -+#ifdef CONFIG_SCHED_SMT -+ leader = NULL; -+ if (cpumask_weight(thread_cpumask(cpu)) > 1) { -+ cpumask_copy(&rq->thread_mask, thread_cpumask(cpu)); -+ cpumask_clear_cpu(cpu, &rq->thread_mask); -+ for_each_cpu(other_cpu, thread_cpumask(cpu)) { -+ if (rqshare == RQSHARE_SMT) { -+ other_rq = cpu_rq(other_cpu); -+ -+ /* Set the smt_leader to the first CPU */ -+ if (!leader) -+ leader = rq; -+ other_rq->smt_leader = leader; -+ } -+ if (rq->cpu_locality[other_cpu] > 1) -+ rq->cpu_locality[other_cpu] = 1; -+ } -+ rq->siblings_idle = siblings_cpu_idle; -+ smt_threads = true; -+ } -+#endif -+ } -+ -+#ifdef CONFIG_SMT_NICE -+ if (smt_threads) { -+ check_siblings = &check_smt_siblings; -+ wake_siblings = &wake_smt_siblings; -+ smt_schedule = &smt_should_schedule; -+ } -+#endif -+ unlock_all_rqs(); -+ local_irq_enable(); -+ mutex_unlock(&sched_domains_mutex); -+ -+ for_each_online_cpu(cpu) { -+ rq = cpu_rq(cpu); -+ -+ for_each_online_cpu(other_cpu) { -+ if (other_cpu <= cpu) -+ continue; -+ printk(KERN_DEBUG "MuQSS locality CPU %d to %d: %d\n", cpu, other_cpu, rq->cpu_locality[other_cpu]); -+ } -+ } -+ -+ for_each_online_cpu(cpu) { -+ rq = cpu_rq(cpu); -+ leader = rq->smp_leader; -+ -+ rq_lock(rq); -+ if (leader && rq != leader) { -+ printk(KERN_INFO "Sharing SMP runqueue from CPU %d to CPU %d\n", -+ leader->cpu, rq->cpu); -+ kfree(rq->node); -+ kfree(rq->sl); -+ kfree(rq->lock); -+ rq->node = leader->node; -+ rq->sl = leader->sl; -+ rq->lock = leader->lock; -+ barrier(); -+ /* To make up for not unlocking the freed runlock */ -+ preempt_enable(); -+ } else -+ rq_unlock(rq); -+ } -+ -+#ifdef CONFIG_SCHED_MC -+ for_each_online_cpu(cpu) { -+ rq = cpu_rq(cpu); -+ leader = rq->mc_leader; -+ -+ rq_lock(rq); -+ if (leader && rq != leader) { -+ printk(KERN_INFO "Sharing MC runqueue from CPU %d to CPU %d\n", -+ leader->cpu, rq->cpu); -+ kfree(rq->node); -+ kfree(rq->sl); -+ kfree(rq->lock); -+ rq->node = leader->node; -+ rq->sl = leader->sl; -+ rq->lock = leader->lock; -+ barrier(); -+ /* To make up for not unlocking the freed runlock */ -+ preempt_enable(); -+ } else -+ rq_unlock(rq); -+ } -+#endif /* CONFIG_SCHED_MC */ -+ -+#ifdef CONFIG_SCHED_SMT -+ for_each_online_cpu(cpu) { -+ rq = cpu_rq(cpu); -+ -+ leader = rq->smt_leader; -+ -+ rq_lock(rq); -+ if (leader && rq != leader) { -+ printk(KERN_INFO "Sharing SMT runqueue from CPU %d to CPU %d\n", -+ leader->cpu, rq->cpu); -+ kfree(rq->node); -+ kfree(rq->sl); -+ kfree(rq->lock); -+ rq->node = leader->node; -+ rq->sl = leader->sl; -+ rq->lock = leader->lock; -+ barrier(); -+ /* To make up for not unlocking the freed runlock */ -+ preempt_enable(); -+ } else -+ rq_unlock(rq); -+ } -+#endif /* CONFIG_SCHED_SMT */ -+ -+ total_runqueues = 0; -+ for_each_possible_cpu(cpu) { -+ int locality, total_rqs = 0, total_cpus = 0; -+ -+ rq = cpu_rq(cpu); -+ if ( -+#ifdef CONFIG_SCHED_MC -+ (rq->mc_leader == rq) && -+#endif -+#ifdef CONFIG_SCHED_SMT -+ (rq->smt_leader == rq) && -+#endif -+ (rq->smp_leader == rq)) -+ total_runqueues++; -+ -+ for (locality = 0; locality <= 4; locality++) { -+ int test_cpu; -+ -+ for_each_possible_cpu(test_cpu) { -+ /* Work from each CPU up instead of every rq -+ * starting at CPU 0 */ -+ other_cpu = test_cpu + cpu; -+ other_cpu %= num_possible_cpus(); -+ other_rq = cpu_rq(other_cpu); -+ -+ if (rq->cpu_locality[other_cpu] == locality) { -+ rq->cpu_order[total_cpus++] = other_rq; -+ if ( -+ -+#ifdef CONFIG_SCHED_MC -+ (other_rq->mc_leader == other_rq) && -+#endif -+#ifdef CONFIG_SCHED_SMT -+ (other_rq->smt_leader == other_rq) && -+#endif -+ (other_rq->smp_leader == other_rq)) -+ rq->rq_order[total_rqs++] = other_rq; -+ } -+ } -+ } -+ } -+ -+ for_each_possible_cpu(cpu) { -+ rq = cpu_rq(cpu); -+ for (i = 0; i < total_runqueues; i++) { -+ printk(KERN_DEBUG "CPU %d RQ order %d RQ %d\n", cpu, i, -+ rq->rq_order[i]->cpu); -+ } -+ } -+ for_each_possible_cpu(cpu) { -+ rq = cpu_rq(cpu); -+ for (i = 0; i < num_possible_cpus(); i++) { -+ printk(KERN_DEBUG "CPU %d CPU order %d RQ %d\n", cpu, i, -+ rq->cpu_order[i]->cpu); -+ } -+ } -+ switch (rqshare) { -+ case RQSHARE_SMP: -+ printk(KERN_INFO "MuQSS runqueue share type SMP total runqueues: %d\n", -+ total_runqueues); -+ break; -+ case RQSHARE_MC: -+ printk(KERN_INFO "MuQSS runqueue share type MC total runqueues: %d\n", -+ total_runqueues); -+ break; -+ case RQSHARE_SMT: -+ printk(KERN_INFO "MuQSS runqueue share type SMT total runqueues: %d\n", -+ total_runqueues); -+ break; -+ case RQSHARE_NONE: -+ printk(KERN_INFO "MuQSS runqueue share type none total runqueues: %d\n", -+ total_runqueues); -+ break; -+ } -+ -+ sched_smp_initialized = true; -+} -+#else -+void __init sched_init_smp(void) -+{ -+ sched_smp_initialized = true; -+} -+#endif /* CONFIG_SMP */ -+ -+int in_sched_functions(unsigned long addr) -+{ -+ return in_lock_functions(addr) || -+ (addr >= (unsigned long)__sched_text_start -+ && addr < (unsigned long)__sched_text_end); -+} -+ -+#ifdef CONFIG_CGROUP_SCHED -+/* task group related information */ -+struct task_group { -+ struct cgroup_subsys_state css; -+ -+ struct rcu_head rcu; -+ struct list_head list; -+ -+ struct task_group *parent; -+ struct list_head siblings; -+ struct list_head children; -+}; -+ -+/* -+ * Default task group. -+ * Every task in system belongs to this group at bootup. -+ */ -+struct task_group root_task_group; -+LIST_HEAD(task_groups); -+ -+/* Cacheline aligned slab cache for task_group */ -+static struct kmem_cache *task_group_cache __read_mostly; -+#endif /* CONFIG_CGROUP_SCHED */ -+ -+void __init sched_init(void) -+{ -+#ifdef CONFIG_SMP -+ int cpu_ids; -+#endif -+ int i; -+ struct rq *rq; -+ -+ wait_bit_init(); -+ -+ prio_ratios[0] = 128; -+ for (i = 1 ; i < NICE_WIDTH ; i++) -+ prio_ratios[i] = prio_ratios[i - 1] * 11 / 10; -+ -+ skiplist_node_init(&init_task.node); -+ -+#ifdef CONFIG_SMP -+ init_defrootdomain(); -+ cpumask_clear(&cpu_idle_map); -+#else -+ uprq = &per_cpu(runqueues, 0); -+#endif -+ -+#ifdef CONFIG_CGROUP_SCHED -+ task_group_cache = KMEM_CACHE(task_group, 0); -+ -+ list_add(&root_task_group.list, &task_groups); -+ INIT_LIST_HEAD(&root_task_group.children); -+ INIT_LIST_HEAD(&root_task_group.siblings); -+#endif /* CONFIG_CGROUP_SCHED */ -+ for_each_possible_cpu(i) { -+ rq = cpu_rq(i); -+ rq->node = kmalloc(sizeof(skiplist_node), GFP_ATOMIC); -+ skiplist_init(rq->node); -+ rq->sl = new_skiplist(rq->node); -+ rq->lock = kmalloc(sizeof(raw_spinlock_t), GFP_ATOMIC); -+ raw_spin_lock_init(rq->lock); -+ rq->nr_running = 0; -+ rq->nr_uninterruptible = 0; -+ rq->nr_switches = 0; -+ rq->clock = rq->old_clock = rq->last_niffy = rq->niffies = 0; -+ rq->last_jiffy = jiffies; -+ rq->user_ns = rq->nice_ns = rq->softirq_ns = rq->system_ns = -+ rq->iowait_ns = rq->idle_ns = 0; -+ rq->dither = 0; -+ set_rq_task(rq, &init_task); -+ rq->iso_ticks = 0; -+ rq->iso_refractory = false; -+#ifdef CONFIG_SMP -+ rq->smp_leader = rq; -+#ifdef CONFIG_SCHED_MC -+ rq->mc_leader = rq; -+#endif -+#ifdef CONFIG_SCHED_SMT -+ rq->smt_leader = rq; -+#endif -+ rq->sd = NULL; -+ rq->rd = NULL; -+ rq->online = false; -+ rq->cpu = i; -+ rq_attach_root(rq, &def_root_domain); -+#endif -+ init_rq_hrexpiry(rq); -+ atomic_set(&rq->nr_iowait, 0); -+ } -+ -+#ifdef CONFIG_SMP -+ 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 -+ rq->siblings_idle = sole_cpu_idle; -+#endif -+#ifdef CONFIG_SCHED_MC -+ rq->cache_idle = sole_cpu_idle; -+#endif -+ rq->cpu_locality = kmalloc(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; -+ } -+ rq->rq_order = kmalloc(cpu_ids * sizeof(struct rq *), GFP_ATOMIC); -+ rq->cpu_order = kmalloc(cpu_ids * sizeof(struct rq *), GFP_ATOMIC); -+ rq->rq_order[0] = rq->cpu_order[0] = rq; -+ for (j = 1; j < cpu_ids; j++) -+ rq->rq_order[j] = rq->cpu_order[j] = cpu_rq(j); -+ } -+#endif -+ -+ /* -+ * The boot idle thread does lazy MMU switching as well: -+ */ -+ mmgrab(&init_mm); -+ 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 -+ idle_thread_set_boot_cpu(); -+#endif /* SMP */ -+ -+ init_schedstats(); -+} -+ -+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP -+static inline int preempt_count_equals(int preempt_offset) -+{ -+ int nested = preempt_count() + rcu_preempt_depth(); -+ -+ return (nested == preempt_offset); -+} -+ -+void __might_sleep(const char *file, int line, int preempt_offset) -+{ -+ /* -+ * Blocking primitives will set (and therefore destroy) current->state, -+ * since we will exit with TASK_RUNNING make sure we enter with it, -+ * otherwise we will destroy state. -+ */ -+ WARN_ONCE(current->state != TASK_RUNNING && current->task_state_change, -+ "do not call blocking ops when !TASK_RUNNING; " -+ "state=%lx set at [<%p>] %pS\n", -+ current->state, -+ (void *)current->task_state_change, -+ (void *)current->task_state_change); -+ -+ ___might_sleep(file, line, preempt_offset); -+} -+EXPORT_SYMBOL(__might_sleep); -+ -+void ___might_sleep(const char *file, int line, int preempt_offset) -+{ -+ /* Ratelimiting timestamp: */ -+ static unsigned long prev_jiffy; -+ -+ unsigned long preempt_disable_ip; -+ -+ /* WARN_ON_ONCE() by default, no rate limit required: */ -+ rcu_sleep_check(); -+ -+ if ((preempt_count_equals(preempt_offset) && !irqs_disabled() && -+ !is_idle_task(current)) || -+ system_state == SYSTEM_BOOTING || system_state > SYSTEM_RUNNING || -+ oops_in_progress) -+ return; -+ -+ if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy) -+ return; -+ prev_jiffy = jiffies; -+ -+ /* Save this before calling printk(), since that will clobber it: */ -+ preempt_disable_ip = get_preempt_disable_ip(current); -+ -+ 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); -+ -+ if (task_stack_end_corrupted(current)) -+ printk(KERN_EMERG "Thread overran stack, or stack corrupted\n"); -+ -+ debug_show_held_locks(current); -+ if (irqs_disabled()) -+ print_irqtrace_events(current); -+ if (IS_ENABLED(CONFIG_DEBUG_PREEMPT) -+ && !preempt_count_equals(preempt_offset)) { -+ pr_err("Preemption disabled at:"); -+ print_ip_sym(preempt_disable_ip); -+ pr_cont("\n"); -+ } -+ dump_stack(); -+ add_taint(TAINT_WARN, LOCKDEP_STILL_OK); -+} -+EXPORT_SYMBOL(___might_sleep); -+#endif -+ -+#ifdef CONFIG_MAGIC_SYSRQ -+static inline void normalise_rt_tasks(void) -+{ -+ struct task_struct *g, *p; -+ unsigned long flags; -+ struct rq *rq; -+ -+ read_lock(&tasklist_lock); -+ for_each_process_thread(g, p) { -+ /* -+ * Only normalize user tasks: -+ */ -+ if (p->flags & PF_KTHREAD) -+ continue; -+ -+ if (!rt_task(p) && !iso_task(p)) -+ continue; -+ -+ rq = task_rq_lock(p, &flags); -+ __setscheduler(p, rq, SCHED_NORMAL, 0, false); -+ task_rq_unlock(rq, p, &flags); -+ } -+ read_unlock(&tasklist_lock); -+} -+ -+void normalize_rt_tasks(void) -+{ -+ normalise_rt_tasks(); -+} -+#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! -+ * -+ * Return: The current task for @cpu. -+ */ -+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 ia64_set_curr_task(int cpu, struct task_struct *p) -+{ -+ cpu_curr(cpu) = p; -+} -+ -+#endif -+ -+void init_idle_bootup_task(struct task_struct *idle) -+{} -+ -+#ifdef CONFIG_SCHED_DEBUG -+__read_mostly bool sched_debug_enabled; -+ -+void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns, -+ 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 -+ -+#ifdef CONFIG_CGROUP_SCHED -+static void sched_free_group(struct task_group *tg) -+{ -+ kmem_cache_free(task_group_cache, tg); -+} -+ -+/* allocate runqueue etc for a new task group */ -+struct task_group *sched_create_group(struct task_group *parent) -+{ -+ struct task_group *tg; -+ -+ tg = kmem_cache_alloc(task_group_cache, GFP_KERNEL | __GFP_ZERO); -+ if (!tg) -+ return ERR_PTR(-ENOMEM); -+ -+ return tg; -+} -+ -+void sched_online_group(struct task_group *tg, struct task_group *parent) -+{ -+} -+ -+/* rcu callback to free various structures associated with a task group */ -+static void sched_free_group_rcu(struct rcu_head *rhp) -+{ -+ /* Now it should be safe to free those cfs_rqs */ -+ sched_free_group(container_of(rhp, struct task_group, rcu)); -+} -+ -+void sched_destroy_group(struct task_group *tg) -+{ -+ /* Wait for possible concurrent references to cfs_rqs complete */ -+ call_rcu(&tg->rcu, sched_free_group_rcu); -+} -+ -+void sched_offline_group(struct task_group *tg) -+{ -+} -+ -+static inline struct task_group *css_tg(struct cgroup_subsys_state *css) -+{ -+ return css ? container_of(css, struct task_group, css) : NULL; -+} -+ -+static struct cgroup_subsys_state * -+cpu_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) -+{ -+ struct task_group *parent = css_tg(parent_css); -+ struct task_group *tg; -+ -+ if (!parent) { -+ /* This is early initialization for the top cgroup */ -+ return &root_task_group.css; -+ } -+ -+ tg = sched_create_group(parent); -+ if (IS_ERR(tg)) -+ return ERR_PTR(-ENOMEM); -+ return &tg->css; -+} -+ -+/* Expose task group only after completing cgroup initialization */ -+static int cpu_cgroup_css_online(struct cgroup_subsys_state *css) -+{ -+ struct task_group *tg = css_tg(css); -+ struct task_group *parent = css_tg(css->parent); -+ -+ if (parent) -+ sched_online_group(tg, parent); -+ return 0; -+} -+ -+static void cpu_cgroup_css_released(struct cgroup_subsys_state *css) -+{ -+ struct task_group *tg = css_tg(css); -+ -+ sched_offline_group(tg); -+} -+ -+static void cpu_cgroup_css_free(struct cgroup_subsys_state *css) -+{ -+ struct task_group *tg = css_tg(css); -+ -+ /* -+ * Relies on the RCU grace period between css_released() and this. -+ */ -+ sched_free_group(tg); -+} -+ -+static void cpu_cgroup_fork(struct task_struct *task) -+{ -+} -+ -+static int cpu_cgroup_can_attach(struct cgroup_taskset *tset) -+{ -+ return 0; -+} -+ -+static void cpu_cgroup_attach(struct cgroup_taskset *tset) -+{ -+} -+ -+static struct cftype cpu_legacy_files[] = { -+ { } /* Terminate */ -+}; -+ -+static struct cftype cpu_files[] = { -+ { } /* terminate */ -+}; -+ -+static int cpu_extra_stat_show(struct seq_file *sf, -+ struct cgroup_subsys_state *css) -+{ -+ return 0; -+} -+ -+struct cgroup_subsys cpu_cgrp_subsys = { -+ .css_alloc = cpu_cgroup_css_alloc, -+ .css_online = cpu_cgroup_css_online, -+ .css_released = cpu_cgroup_css_released, -+ .css_free = cpu_cgroup_css_free, -+ .css_extra_stat_show = cpu_extra_stat_show, -+ .fork = cpu_cgroup_fork, -+ .can_attach = cpu_cgroup_can_attach, -+ .attach = cpu_cgroup_attach, -+ .legacy_cftypes = cpu_files, -+ .legacy_cftypes = cpu_legacy_files, -+ .dfl_cftypes = cpu_files, -+ .early_init = true, -+ .threaded = true, -+}; -+#endif /* CONFIG_CGROUP_SCHED */ -+ -+#undef CREATE_TRACE_POINTS -diff -Nur a/kernel/sched/MuQSS.h b/kernel/sched/MuQSS.h ---- a/kernel/sched/MuQSS.h 1970-01-01 01:00:00.000000000 +0100 -+++ b/kernel/sched/MuQSS.h 2019-02-09 17:46:12.001297867 +0000 -@@ -0,0 +1,881 @@ -+/* SPDX-License-Identifier: GPL-2.0 */ -+#ifndef MUQSS_SCHED_H -+#define MUQSS_SCHED_H -+ -+#include <linux/sched/clock.h> -+#include <linux/sched/wake_q.h> -+#include <linux/sched/signal.h> -+#include <linux/sched/mm.h> -+#include <linux/sched/cpufreq.h> -+#include <linux/sched/stat.h> -+#include <linux/sched/nohz.h> -+#include <linux/sched/debug.h> -+#include <linux/sched/hotplug.h> -+#include <linux/sched/task.h> -+#include <linux/sched/task_stack.h> -+#include <linux/sched/topology.h> -+#include <linux/sched/cputime.h> -+#include <linux/sched/init.h> -+#include <linux/sched/isolation.h> -+ -+#include <uapi/linux/sched/types.h> -+ -+#include <linux/cgroup.h> -+#include <linux/cpufreq.h> -+#include <linux/cpuidle.h> -+#include <linux/ctype.h> -+#include <linux/freezer.h> -+#include <linux/interrupt.h> -+#include <linux/kernel_stat.h> -+#include <linux/kthread.h> -+#include <linux/livepatch.h> -+#include <linux/proc_fs.h> -+#include <linux/sched.h> -+#include <linux/slab.h> -+#include <linux/skip_list.h> -+#include <linux/stackprotector.h> -+#include <linux/stop_machine.h> -+#include <linux/suspend.h> -+#include <linux/swait.h> -+#include <linux/tick.h> -+#include <linux/tsacct_kern.h> -+#include <linux/u64_stats_sync.h> -+ -+#ifdef CONFIG_PARAVIRT -+#include <asm/paravirt.h> -+#endif -+ -+#include "cpupri.h" -+ -+#ifdef CONFIG_SCHED_DEBUG -+# define SCHED_WARN_ON(x) WARN_ONCE(x, #x) -+#else -+# define SCHED_WARN_ON(x) ((void)(x)) -+#endif -+ -+/* task_struct::on_rq states: */ -+#define TASK_ON_RQ_QUEUED 1 -+#define TASK_ON_RQ_MIGRATING 2 -+ -+struct rq; -+ -+#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING) -+#define HAVE_SCHED_AVG_IRQ -+#endif -+ -+#ifdef CONFIG_SMP -+ -+static inline bool sched_asym_prefer(int a, int b) -+{ -+ return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); -+} -+ -+/* -+ * 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; -+ -+ /* Indicate more than one runnable task for any CPU */ -+ bool overload; -+ -+ /* -+ * The bit corresponding to a CPU gets set here if such CPU has more -+ * than one runnable -deadline task (as it is below for RT tasks). -+ */ -+ cpumask_var_t dlo_mask; -+ atomic_t dlo_count; -+ /* Replace unused CFS structures with void */ -+ //struct dl_bw dl_bw; -+ //struct cpudl cpudl; -+ void *dl_bw; -+ void *cpudl; -+ -+ /* -+ * 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; -+ void *cpupri; -+ -+ unsigned long max_cpu_capacity; -+}; -+ -+extern struct root_domain def_root_domain; -+extern struct mutex sched_domains_mutex; -+ -+extern void init_defrootdomain(void); -+extern int sched_init_domains(const struct cpumask *cpu_map); -+extern void rq_attach_root(struct rq *rq, struct root_domain *rd); -+ -+static inline void cpupri_cleanup(void __maybe_unused *cpupri) -+{ -+} -+ -+static inline void cpudl_cleanup(void __maybe_unused *cpudl) -+{ -+} -+ -+static inline void init_dl_bw(void __maybe_unused *dl_bw) -+{ -+} -+ -+static inline int cpudl_init(void __maybe_unused *dl_bw) -+{ -+ return 0; -+} -+ -+static inline int cpupri_init(void __maybe_unused *cpupri) -+{ -+ return 0; -+} -+#endif /* CONFIG_SMP */ -+ -+/* -+ * This is the main, per-CPU runqueue data structure. -+ * This data should only be modified by the local cpu. -+ */ -+struct rq { -+ raw_spinlock_t *lock; -+ raw_spinlock_t *orig_lock; -+ -+ struct task_struct *curr, *idle, *stop; -+ struct mm_struct *prev_mm; -+ -+ unsigned int nr_running; -+ /* -+ * This is part of a global counter where only the total sum -+ * over all CPUs matters. A task can increase this counter on -+ * one CPU and if it got migrated afterwards it may decrease -+ * it on another CPU. Always updated under the runqueue lock: -+ */ -+ unsigned long nr_uninterruptible; -+ u64 nr_switches; -+ -+ /* Stored data about rq->curr to work outside rq lock */ -+ u64 rq_deadline; -+ int rq_prio; -+ -+ /* Best queued id for use outside lock */ -+ u64 best_key; -+ -+ unsigned long last_scheduler_tick; /* Last jiffy this RQ ticked */ -+ unsigned long last_jiffy; /* Last jiffy this RQ updated rq clock */ -+ u64 niffies; /* Last time this RQ updated rq clock */ -+ u64 last_niffy; /* Last niffies as updated by local clock */ -+ u64 last_jiffy_niffies; /* Niffies @ last_jiffy */ -+ -+ u64 load_update; /* When we last updated load */ -+ unsigned long load_avg; /* Rolling load average */ -+#ifdef HAVE_SCHED_AVG_IRQ -+ u64 irq_load_update; /* When we last updated IRQ load */ -+ unsigned long irq_load_avg; /* Rolling IRQ load average */ -+#endif -+#ifdef CONFIG_SMT_NICE -+ struct mm_struct *rq_mm; -+ int rq_smt_bias; /* Policy/nice level bias across smt siblings */ -+#endif -+ /* Accurate timekeeping data */ -+ unsigned long user_ns, nice_ns, irq_ns, softirq_ns, system_ns, -+ iowait_ns, idle_ns; -+ atomic_t nr_iowait; -+ -+ skiplist_node *node; -+ skiplist *sl; -+#ifdef CONFIG_SMP -+ struct task_struct *preempt; /* Preempt triggered on this task */ -+ struct task_struct *preempting; /* Hint only, what task is preempting */ -+ -+ int cpu; /* cpu of this runqueue */ -+ bool online; -+ -+ struct root_domain *rd; -+ struct sched_domain *sd; -+ -+ unsigned long cpu_capacity_orig; -+ -+ int *cpu_locality; /* CPU relative cache distance */ -+ struct rq **rq_order; /* Shared RQs ordered by relative cache distance */ -+ struct rq **cpu_order; /* RQs of discrete CPUs ordered by distance */ -+ -+ struct rq *smp_leader; /* First physical CPU per node */ -+#ifdef CONFIG_SCHED_SMT -+ struct rq *smt_leader; /* First logical CPU in SMT siblings */ -+ cpumask_t thread_mask; -+ bool (*siblings_idle)(struct rq *rq); -+ /* See if all smt siblings are idle */ -+#endif /* CONFIG_SCHED_SMT */ -+#ifdef CONFIG_SCHED_MC -+ struct rq *mc_leader; /* First logical CPU in MC siblings */ -+ cpumask_t core_mask; -+ bool (*cache_idle)(struct rq *rq); -+ /* See if all cache siblings are idle */ -+#endif /* CONFIG_SCHED_MC */ -+#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; -+ int dither; -+ -+ int iso_ticks; -+ bool iso_refractory; -+ -+#ifdef CONFIG_HIGH_RES_TIMERS -+ struct hrtimer hrexpiry_timer; -+#endif -+ -+ int rt_nr_running; /* Number real time tasks running */ -+#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 */ -+ -+#ifdef CONFIG_SMP -+ struct llist_head wake_list; -+#endif -+ -+#ifdef CONFIG_CPU_IDLE -+ /* Must be inspected within a rcu lock section */ -+ struct cpuidle_state *idle_state; -+#endif -+}; -+ -+#ifdef CONFIG_SMP -+struct rq *cpu_rq(int cpu); -+#endif -+ -+#ifndef CONFIG_SMP -+extern struct rq *uprq; -+#define cpu_rq(cpu) (uprq) -+#define this_rq() (uprq) -+#define raw_rq() (uprq) -+#define task_rq(p) (uprq) -+#define cpu_curr(cpu) ((uprq)->curr) -+#else /* CONFIG_SMP */ -+DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); -+#define this_rq() this_cpu_ptr(&runqueues) -+#define raw_rq() raw_cpu_ptr(&runqueues) -+#define task_rq(p) cpu_rq(task_cpu(p)) -+#endif /* CONFIG_SMP */ -+ -+static inline int task_current(struct rq *rq, struct task_struct *p) -+{ -+ return rq->curr == p; -+} -+ -+static inline int task_running(struct rq *rq, struct task_struct *p) -+{ -+#ifdef CONFIG_SMP -+ return p->on_cpu; -+#else -+ return task_current(rq, p); -+#endif -+} -+ -+static inline void rq_lock(struct rq *rq) -+ __acquires(rq->lock) -+{ -+ raw_spin_lock(rq->lock); -+} -+ -+static inline void rq_unlock(struct rq *rq) -+ __releases(rq->lock) -+{ -+ raw_spin_unlock(rq->lock); -+} -+ -+static inline void rq_lock_irq(struct rq *rq) -+ __acquires(rq->lock) -+{ -+ raw_spin_lock_irq(rq->lock); -+} -+ -+static inline void rq_unlock_irq(struct rq *rq) -+ __releases(rq->lock) -+{ -+ raw_spin_unlock_irq(rq->lock); -+} -+ -+static inline void rq_lock_irqsave(struct rq *rq, unsigned long *flags) -+ __acquires(rq->lock) -+{ -+ raw_spin_lock_irqsave(rq->lock, *flags); -+} -+ -+static inline void rq_unlock_irqrestore(struct rq *rq, unsigned long *flags) -+ __releases(rq->lock) -+{ -+ raw_spin_unlock_irqrestore(rq->lock, *flags); -+} -+ -+static inline struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags) -+ __acquires(p->pi_lock) -+ __acquires(rq->lock) -+{ -+ struct rq *rq; -+ -+ while (42) { -+ raw_spin_lock_irqsave(&p->pi_lock, *flags); -+ rq = task_rq(p); -+ raw_spin_lock(rq->lock); -+ if (likely(rq == task_rq(p))) -+ break; -+ raw_spin_unlock(rq->lock); -+ raw_spin_unlock_irqrestore(&p->pi_lock, *flags); -+ } -+ return rq; -+} -+ -+static inline void task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags) -+ __releases(rq->lock) -+ __releases(p->pi_lock) -+{ -+ rq_unlock(rq); -+ raw_spin_unlock_irqrestore(&p->pi_lock, *flags); -+} -+ -+static inline struct rq *__task_rq_lock(struct task_struct *p) -+ __acquires(rq->lock) -+{ -+ struct rq *rq; -+ -+ lockdep_assert_held(&p->pi_lock); -+ -+ while (42) { -+ rq = task_rq(p); -+ raw_spin_lock(rq->lock); -+ if (likely(rq == task_rq(p))) -+ break; -+ raw_spin_unlock(rq->lock); -+ } -+ return rq; -+} -+ -+static inline void __task_rq_unlock(struct rq *rq) -+{ -+ rq_unlock(rq); -+} -+ -+/* -+ * {de,en}queue flags: Most not used on MuQSS. -+ * -+ * DEQUEUE_SLEEP - task is no longer runnable -+ * ENQUEUE_WAKEUP - task just became runnable -+ * -+ * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks -+ * are in a known state which allows modification. Such pairs -+ * should preserve as much state as possible. -+ * -+ * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location -+ * in the runqueue. -+ * -+ * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) -+ * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) -+ * ENQUEUE_MIGRATED - the task was migrated during wakeup -+ * -+ */ -+ -+#define DEQUEUE_SAVE 0x02 /* matches ENQUEUE_RESTORE */ -+ -+#define ENQUEUE_RESTORE 0x02 -+ -+static inline u64 __rq_clock_broken(struct rq *rq) -+{ -+ return READ_ONCE(rq->clock); -+} -+ -+static inline u64 rq_clock(struct rq *rq) -+{ -+ lockdep_assert_held(rq->lock); -+ -+ return rq->clock; -+} -+ -+static inline u64 rq_clock_task(struct rq *rq) -+{ -+ lockdep_assert_held(rq->lock); -+ -+ return rq->clock_task; -+} -+ -+#ifdef CONFIG_NUMA -+enum numa_topology_type { -+ NUMA_DIRECT, -+ NUMA_GLUELESS_MESH, -+ NUMA_BACKPLANE, -+}; -+extern enum numa_topology_type sched_numa_topology_type; -+extern int sched_max_numa_distance; -+extern bool find_numa_distance(int distance); -+ -+extern void sched_init_numa(void); -+extern void sched_domains_numa_masks_set(unsigned int cpu); -+extern void sched_domains_numa_masks_clear(unsigned int cpu); -+#else -+static inline void sched_init_numa(void) { } -+static inline void sched_domains_numa_masks_set(unsigned int cpu) { } -+static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } -+#endif -+ -+extern struct mutex sched_domains_mutex; -+extern struct static_key_false sched_schedstats; -+ -+#define rcu_dereference_check_sched_domain(p) \ -+ rcu_dereference_check((p), \ -+ lockdep_is_held(&sched_domains_mutex)) -+ -+#ifdef CONFIG_SMP -+ -+/* -+ * 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) -+ -+#define for_each_lower_domain(sd) for (; sd; sd = sd->child) -+ -+/** -+ * highest_flag_domain - Return highest sched_domain containing flag. -+ * @cpu: The cpu whose highest level of sched domain is to -+ * be returned. -+ * @flag: The flag to check for the highest sched_domain -+ * for the given cpu. -+ * -+ * Returns the highest sched_domain of a cpu which contains the given flag. -+ */ -+static inline struct sched_domain *highest_flag_domain(int cpu, int flag) -+{ -+ struct sched_domain *sd, *hsd = NULL; -+ -+ for_each_domain(cpu, sd) { -+ if (!(sd->flags & flag)) -+ break; -+ hsd = sd; -+ } -+ -+ return hsd; -+} -+ -+static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) -+{ -+ struct sched_domain *sd; -+ -+ for_each_domain(cpu, sd) { -+ if (sd->flags & flag) -+ break; -+ } -+ -+ return sd; -+} -+ -+DECLARE_PER_CPU(struct sched_domain *, sd_llc); -+DECLARE_PER_CPU(int, sd_llc_size); -+DECLARE_PER_CPU(int, sd_llc_id); -+DECLARE_PER_CPU(struct sched_domain_shared *, sd_llc_shared); -+DECLARE_PER_CPU(struct sched_domain *, sd_numa); -+DECLARE_PER_CPU(struct sched_domain *, sd_asym); -+ -+struct sched_group_capacity { -+ atomic_t ref; -+ /* -+ * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity -+ * for a single CPU. -+ */ -+ unsigned long capacity; -+ unsigned long min_capacity; /* Min per-CPU capacity in group */ -+ unsigned long next_update; -+ int imbalance; /* XXX unrelated to capacity but shared group state */ -+ -+#ifdef CONFIG_SCHED_DEBUG -+ int id; -+#endif -+ -+ unsigned long cpumask[0]; /* balance mask */ -+}; -+ -+struct sched_group { -+ struct sched_group *next; /* Must be a circular list */ -+ atomic_t ref; -+ -+ unsigned int group_weight; -+ struct sched_group_capacity *sgc; -+ int asym_prefer_cpu; /* cpu of highest priority in group */ -+ -+ /* -+ * The CPUs this group covers. -+ * -+ * NOTE: this field is variable length. (Allocated dynamically -+ * by attaching extra space to the end of the structure, -+ * depending on how many CPUs the kernel has booted up with) -+ */ -+ unsigned long cpumask[0]; -+}; -+ -+static inline struct cpumask *sched_group_span(struct sched_group *sg) -+{ -+ return to_cpumask(sg->cpumask); -+} -+ -+/* -+ * See build_balance_mask(). -+ */ -+static inline struct cpumask *group_balance_mask(struct sched_group *sg) -+{ -+ return to_cpumask(sg->sgc->cpumask); -+} -+ -+/** -+ * group_first_cpu - Returns the first cpu in the cpumask of a sched_group. -+ * @group: The group whose first cpu is to be returned. -+ */ -+static inline unsigned int group_first_cpu(struct sched_group *group) -+{ -+ return cpumask_first(sched_group_span(group)); -+} -+ -+ -+#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL) -+void register_sched_domain_sysctl(void); -+void dirty_sched_domain_sysctl(int cpu); -+void unregister_sched_domain_sysctl(void); -+#else -+static inline void register_sched_domain_sysctl(void) -+{ -+} -+static inline void dirty_sched_domain_sysctl(int cpu) -+{ -+} -+static inline void unregister_sched_domain_sysctl(void) -+{ -+} -+#endif -+ -+extern void sched_ttwu_pending(void); -+extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask); -+extern void set_rq_online (struct rq *rq); -+extern void set_rq_offline(struct rq *rq); -+extern bool sched_smp_initialized; -+ -+static inline void update_group_capacity(struct sched_domain *sd, int cpu) -+{ -+} -+ -+static inline void trigger_load_balance(struct rq *rq) -+{ -+} -+ -+#define sched_feat(x) 0 -+ -+#else /* CONFIG_SMP */ -+ -+static inline void sched_ttwu_pending(void) { } -+ -+#endif /* CONFIG_SMP */ -+ -+#ifdef CONFIG_CPU_IDLE -+static inline void idle_set_state(struct rq *rq, -+ struct cpuidle_state *idle_state) -+{ -+ rq->idle_state = idle_state; -+} -+ -+static inline struct cpuidle_state *idle_get_state(struct rq *rq) -+{ -+ SCHED_WARN_ON(!rcu_read_lock_held()); -+ return rq->idle_state; -+} -+#else -+static inline void idle_set_state(struct rq *rq, -+ struct cpuidle_state *idle_state) -+{ -+} -+ -+static inline struct cpuidle_state *idle_get_state(struct rq *rq) -+{ -+ return NULL; -+} -+#endif -+ -+#ifdef CONFIG_SCHED_DEBUG -+extern bool sched_debug_enabled; -+#endif -+ -+extern void schedule_idle(void); -+ -+#ifdef CONFIG_IRQ_TIME_ACCOUNTING -+struct irqtime { -+ u64 total; -+ u64 tick_delta; -+ u64 irq_start_time; -+ struct u64_stats_sync sync; -+}; -+ -+DECLARE_PER_CPU(struct irqtime, cpu_irqtime); -+ -+/* -+ * Returns the irqtime minus the softirq time computed by ksoftirqd. -+ * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime -+ * and never move forward. -+ */ -+static inline u64 irq_time_read(int cpu) -+{ -+ struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); -+ unsigned int seq; -+ u64 total; -+ -+ do { -+ seq = __u64_stats_fetch_begin(&irqtime->sync); -+ total = irqtime->total; -+ } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); -+ -+ return total; -+} -+#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ -+ -+#ifdef CONFIG_SMP -+static inline int cpu_of(struct rq *rq) -+{ -+ return rq->cpu; -+} -+#else /* CONFIG_SMP */ -+static inline int cpu_of(struct rq *rq) -+{ -+ return 0; -+} -+#endif -+ -+#ifdef CONFIG_CPU_FREQ -+DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data); -+ -+static inline void cpufreq_trigger(struct rq *rq, unsigned int flags) -+{ -+ struct update_util_data *data; -+ -+ data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, -+ cpu_of(rq))); -+ -+ if (data) -+ data->func(data, rq->niffies, flags); -+} -+#else -+static inline void cpufreq_trigger(struct rq *rq, unsigned int flag) -+{ -+} -+#endif /* CONFIG_CPU_FREQ */ -+ -+#ifdef arch_scale_freq_capacity -+#ifndef arch_scale_freq_invariant -+#define arch_scale_freq_invariant() (true) -+#endif -+#else /* arch_scale_freq_capacity */ -+#define arch_scale_freq_invariant() (false) -+#endif -+ -+/* -+ * This should only be called when current == rq->idle. Dodgy workaround for -+ * when softirqs are pending and we are in the idle loop. Setting current to -+ * resched will kick us out of the idle loop and the softirqs will be serviced -+ * on our next pass through schedule(). -+ */ -+static inline bool softirq_pending(int cpu) -+{ -+ if (likely(!local_softirq_pending())) -+ return false; -+ set_tsk_need_resched(current); -+ return true; -+} -+ -+#ifdef CONFIG_64BIT -+static inline u64 read_sum_exec_runtime(struct task_struct *t) -+{ -+ return tsk_seruntime(t); -+} -+#else -+struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags); -+void task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags); -+ -+static inline u64 read_sum_exec_runtime(struct task_struct *t) -+{ -+ unsigned long flags; -+ u64 ns; -+ struct rq *rq; -+ -+ rq = task_rq_lock(t, &flags); -+ ns = tsk_seruntime(t); -+ task_rq_unlock(rq, t, &flags); -+ -+ return ns; -+} -+#endif -+ -+#ifndef arch_scale_freq_capacity -+static __always_inline -+unsigned long arch_scale_freq_capacity(int cpu) -+{ -+ return SCHED_CAPACITY_SCALE; -+} -+#endif -+ -+#ifdef CONFIG_NO_HZ_FULL -+extern bool sched_can_stop_tick(struct rq *rq); -+extern int __init sched_tick_offload_init(void); -+ -+/* -+ * Tick may be needed by tasks in the runqueue depending on their policy and -+ * requirements. If tick is needed, lets send the target an IPI to kick it out of -+ * nohz mode if necessary. -+ */ -+static inline void sched_update_tick_dependency(struct rq *rq) -+{ -+ int cpu; -+ -+ if (!tick_nohz_full_enabled()) -+ return; -+ -+ cpu = cpu_of(rq); -+ -+ if (!tick_nohz_full_cpu(cpu)) -+ return; -+ -+ if (sched_can_stop_tick(rq)) -+ tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); -+ else -+ tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); -+} -+#else -+static inline int sched_tick_offload_init(void) { return 0; } -+static inline void sched_update_tick_dependency(struct rq *rq) { } -+#endif -+ -+#ifdef CONFIG_SMP -+ -+#ifndef arch_scale_cpu_capacity -+static __always_inline -+unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) -+{ -+ if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1)) -+ return sd->smt_gain / sd->span_weight; -+ -+ return SCHED_CAPACITY_SCALE; -+} -+#endif -+#else -+#ifndef arch_scale_cpu_capacity -+static __always_inline -+unsigned long arch_scale_cpu_capacity(void __always_unused *sd, int cpu) -+{ -+ return SCHED_CAPACITY_SCALE; -+} -+#endif -+#endif -+ -+#define SCHED_FLAG_SUGOV 0x10000000 -+ -+static inline bool rt_rq_is_runnable(struct rq *rt_rq) -+{ -+ return rt_rq->rt_nr_running; -+} -+ -+#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL -+ -+static inline unsigned long cpu_bw_dl(struct rq *rq) -+{ -+ return 0; -+} -+ -+static inline unsigned long cpu_util_dl(struct rq *rq) -+{ -+ return 0; -+} -+ -+static inline unsigned long cpu_util_cfs(struct rq *rq) -+{ -+ unsigned long ret = READ_ONCE(rq->load_avg); -+ -+ if (ret > SCHED_CAPACITY_SCALE) -+ ret = SCHED_CAPACITY_SCALE; -+ return ret; -+} -+ -+static inline unsigned long cpu_util_rt(struct rq *rq) -+{ -+ unsigned long ret = READ_ONCE(rq->rt_nr_running); -+ -+ if (ret > SCHED_CAPACITY_SCALE) -+ ret = SCHED_CAPACITY_SCALE; -+ return ret; -+} -+ -+#ifdef HAVE_SCHED_AVG_IRQ -+static inline unsigned long cpu_util_irq(struct rq *rq) -+{ -+ unsigned long ret = READ_ONCE(rq->irq_load_avg); -+ -+ if (ret > SCHED_CAPACITY_SCALE) -+ ret = SCHED_CAPACITY_SCALE; -+ return ret; -+} -+ -+static inline -+unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) -+{ -+ util *= (max - irq); -+ util /= max; -+ -+ return util; -+ -+} -+#else -+static inline unsigned long cpu_util_irq(struct rq *rq) -+{ -+ return 0; -+} -+ -+static inline -+unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) -+{ -+ return util; -+} -+#endif -+#endif -+ -+#endif /* MUQSS_SCHED_H */ -diff -Nur a/kernel/sched/sched.h b/kernel/sched/sched.h ---- a/kernel/sched/sched.h 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/sched/sched.h 2019-02-09 17:46:12.001297867 +0000 -@@ -2,6 +2,19 @@ - /* - * Scheduler internal types and methods: - */ -+#ifdef CONFIG_SCHED_MUQSS -+#include "MuQSS.h" -+ -+/* Begin compatibility wrappers for MuQSS/CFS differences */ -+#define rq_rt_nr_running(rq) ((rq)->rt_nr_running) -+#define rq_h_nr_running(rq) ((rq)->nr_running) -+ -+#else /* CONFIG_SCHED_MUQSS */ -+ -+#define rq_rt_nr_running(rq) ((rq)->rt.rt_nr_running) -+#define rq_h_nr_running(rq) ((rq)->cfs.h_nr_running) -+ -+ - #include <linux/sched.h> - - #include <linux/sched/autogroup.h> -@@ -2241,3 +2254,30 @@ - return util; - } - #endif -+ -+/* MuQSS compatibility functions */ -+static inline bool softirq_pending(int cpu) -+{ -+ return false; -+} -+ -+#ifdef CONFIG_64BIT -+static inline u64 read_sum_exec_runtime(struct task_struct *t) -+{ -+ return t->se.sum_exec_runtime; -+} -+#else -+static inline u64 read_sum_exec_runtime(struct task_struct *t) -+{ -+ u64 ns; -+ struct rq_flags rf; -+ struct rq *rq; -+ -+ rq = task_rq_lock(t, &rf); -+ ns = t->se.sum_exec_runtime; -+ task_rq_unlock(rq, t, &rf); -+ -+ return ns; -+} -+#endif -+#endif /* CONFIG_SCHED_MUQSS */ -diff -Nur a/kernel/sched/topology.c b/kernel/sched/topology.c ---- a/kernel/sched/topology.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/sched/topology.c 2019-02-09 17:46:12.001297867 +0000 -@@ -219,7 +219,11 @@ - struct root_domain *old_rd = NULL; - unsigned long flags; - -+#ifdef CONFIG_SCHED_MUQSS -+ raw_spin_lock_irqsave(rq->lock, flags); -+#else - raw_spin_lock_irqsave(&rq->lock, flags); -+#endif - - if (rq->rd) { - old_rd = rq->rd; -@@ -245,7 +249,11 @@ - if (cpumask_test_cpu(rq->cpu, cpu_active_mask)) - set_rq_online(rq); - -+#ifdef CONFIG_SCHED_MUQSS -+ raw_spin_unlock_irqrestore(rq->lock, flags); -+#else - raw_spin_unlock_irqrestore(&rq->lock, flags); -+#endif - - if (old_rd) - call_rcu_sched(&old_rd->rcu, free_rootdomain); -diff -Nur a/kernel/skip_list.c b/kernel/skip_list.c ---- a/kernel/skip_list.c 1970-01-01 01:00:00.000000000 +0100 -+++ b/kernel/skip_list.c 2019-02-09 17:46:12.001297867 +0000 -@@ -0,0 +1,148 @@ -+/* -+ Copyright (C) 2011,2016 Con Kolivas. -+ -+ Code based on example originally by William Pugh. -+ -+Skip Lists are a probabilistic alternative to balanced trees, as -+described in the June 1990 issue of CACM and were invented by -+William Pugh in 1987. -+ -+A couple of comments about this implementation: -+The routine randomLevel has been hard-coded to generate random -+levels using p=0.25. It can be easily changed. -+ -+The insertion routine has been implemented so as to use the -+dirty hack described in the CACM paper: if a random level is -+generated that is more than the current maximum level, the -+current maximum level plus one is used instead. -+ -+Levels start at zero and go up to MaxLevel (which is equal to -+MaxNumberOfLevels-1). -+ -+The routines defined in this file are: -+ -+init: defines slnode -+ -+new_skiplist: returns a new, empty list -+ -+randomLevel: Returns a random level based on a u64 random seed passed to it. -+In MuQSS, the "niffy" time is used for this purpose. -+ -+insert(l,key, value): inserts the binding (key, value) into l. This operation -+occurs in O(log n) time. -+ -+delnode(slnode, l, node): deletes any binding of key from the l based on the -+actual node value. This operation occurs in O(k) time where k is the -+number of levels of the node in question (max 8). The original delete -+function occurred in O(log n) time and involved a search. -+ -+MuQSS Notes: In this implementation of skiplists, there are bidirectional -+next/prev pointers and the insert function returns a pointer to the actual -+node the value is stored. The key here is chosen by the scheduler so as to -+sort tasks according to the priority list requirements and is no longer used -+by the scheduler after insertion. The scheduler lookup, however, occurs in -+O(1) time because it is always the first item in the level 0 linked list. -+Since the task struct stores a copy of the node pointer upon skiplist_insert, -+it can also remove it much faster than the original implementation with the -+aid of prev<->next pointer manipulation and no searching. -+ -+*/ -+ -+#include <linux/slab.h> -+#include <linux/skip_list.h> -+ -+#define MaxNumberOfLevels 8 -+#define MaxLevel (MaxNumberOfLevels - 1) -+ -+void skiplist_init(skiplist_node *slnode) -+{ -+ int i; -+ -+ slnode->key = 0xFFFFFFFFFFFFFFFF; -+ slnode->level = 0; -+ slnode->value = NULL; -+ for (i = 0; i < MaxNumberOfLevels; i++) -+ slnode->next[i] = slnode->prev[i] = slnode; -+} -+ -+skiplist *new_skiplist(skiplist_node *slnode) -+{ -+ skiplist *l = kzalloc(sizeof(skiplist), GFP_ATOMIC); -+ -+ BUG_ON(!l); -+ l->header = slnode; -+ return l; -+} -+ -+void free_skiplist(skiplist *l) -+{ -+ skiplist_node *p, *q; -+ -+ p = l->header; -+ do { -+ q = p->next[0]; -+ p->next[0]->prev[0] = q->prev[0]; -+ skiplist_node_init(p); -+ p = q; -+ } while (p != l->header); -+ kfree(l); -+} -+ -+void skiplist_node_init(skiplist_node *node) -+{ -+ memset(node, 0, sizeof(skiplist_node)); -+} -+ -+static inline unsigned int randomLevel(const long unsigned int randseed) -+{ -+ return find_first_bit(&randseed, MaxLevel) / 2; -+} -+ -+void skiplist_insert(skiplist *l, skiplist_node *node, keyType key, valueType value, unsigned int randseed) -+{ -+ skiplist_node *update[MaxNumberOfLevels]; -+ skiplist_node *p, *q; -+ int k = l->level; -+ -+ p = l->header; -+ do { -+ while (q = p->next[k], q->key <= key) -+ p = q; -+ update[k] = p; -+ } while (--k >= 0); -+ -+ ++l->entries; -+ k = randomLevel(randseed); -+ if (k > l->level) { -+ k = ++l->level; -+ update[k] = l->header; -+ } -+ -+ node->level = k; -+ node->key = key; -+ node->value = value; -+ do { -+ p = update[k]; -+ node->next[k] = p->next[k]; -+ p->next[k] = node; -+ node->prev[k] = p; -+ node->next[k]->prev[k] = node; -+ } while (--k >= 0); -+} -+ -+void skiplist_delete(skiplist *l, skiplist_node *node) -+{ -+ int k, m = node->level; -+ -+ for (k = 0; k <= m; k++) { -+ node->prev[k]->next[k] = node->next[k]; -+ node->next[k]->prev[k] = node->prev[k]; -+ } -+ skiplist_node_init(node); -+ if (m == l->level) { -+ while (l->header->next[m] == l->header && l->header->prev[m] == l->header && m > 0) -+ m--; -+ l->level = m; -+ } -+ l->entries--; -+} -diff -Nur a/kernel/sysctl.c b/kernel/sysctl.c ---- a/kernel/sysctl.c 2019-02-09 17:20:30.491821512 +0000 -+++ b/kernel/sysctl.c 2019-02-09 17:57:37.563468776 +0000 -@@ -136,6 +136,12 @@ - static unsigned long one_ul __read_only = 1; - static int one_hundred __read_only = 100; - static int one_thousand __read_only = 1000; -+#ifdef CONFIG_SCHED_MUQSS -+extern int rr_interval; -+extern int sched_interactive; -+extern int sched_iso_cpu; -+extern int sched_yield_type; -+#endif - #ifdef CONFIG_PRINTK - static int ten_thousand __read_only = 10000; - #endif -@@ -306,7 +312,7 @@ - { } - }; - --#ifdef CONFIG_SCHED_DEBUG -+#if defined(CONFIG_SCHED_DEBUG) && !defined(CONFIG_SCHED_MUQSS) - static int min_sched_granularity_ns __read_only = 100000; /* 100 usecs */ - static int max_sched_granularity_ns __read_only = NSEC_PER_SEC; /* 1 second */ - static int min_wakeup_granularity_ns __read_only; /* 0 usecs */ -@@ -323,6 +329,7 @@ - #endif - - static struct ctl_table kern_table[] = { -+#ifndef CONFIG_SCHED_MUQSS - { - .procname = "sched_child_runs_first", - .data = &sysctl_sched_child_runs_first, -@@ -477,6 +484,7 @@ - .extra1 = &one, - }, - #endif -+#endif /* !CONFIG_SCHED_MUQSS */ - #ifdef CONFIG_PROVE_LOCKING - { - .procname = "prove_locking", -@@ -1082,6 +1090,44 @@ - .proc_handler = proc_dointvec, - }, - #endif -+#ifdef CONFIG_SCHED_MUQSS -+ { -+ .procname = "rr_interval", -+ .data = &rr_interval, -+ .maxlen = sizeof (int), -+ .mode = 0644, -+ .proc_handler = &proc_dointvec_minmax, -+ .extra1 = &one, -+ .extra2 = &one_thousand, -+ }, -+ { -+ .procname = "interactive", -+ .data = &sched_interactive, -+ .maxlen = sizeof(int), -+ .mode = 0644, -+ .proc_handler = &proc_dointvec_minmax, -+ .extra1 = &zero, -+ .extra2 = &one, -+ }, -+ { -+ .procname = "iso_cpu", -+ .data = &sched_iso_cpu, -+ .maxlen = sizeof (int), -+ .mode = 0644, -+ .proc_handler = &proc_dointvec_minmax, -+ .extra1 = &zero, -+ .extra2 = &one_hundred, -+ }, -+ { -+ .procname = "yield_type", -+ .data = &sched_yield_type, -+ .maxlen = sizeof (int), -+ .mode = 0644, -+ .proc_handler = &proc_dointvec_minmax, -+ .extra1 = &zero, -+ .extra2 = &two, -+ }, -+#endif - #if defined(CONFIG_S390) && defined(CONFIG_SMP) - { - .procname = "spin_retry", -diff -Nur a/kernel/time/clockevents.c b/kernel/time/clockevents.c ---- a/kernel/time/clockevents.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/time/clockevents.c 2019-02-09 17:46:12.001297867 +0000 -@@ -198,8 +198,13 @@ - - #ifdef CONFIG_GENERIC_CLOCKEVENTS_MIN_ADJUST - -+#ifdef CONFIG_SCHED_MUQSS -+/* Limit min_delta to 100us */ -+#define MIN_DELTA_LIMIT (NSEC_PER_SEC / 10000) -+#else - /* Limit min_delta to a jiffie */ - #define MIN_DELTA_LIMIT (NSEC_PER_SEC / HZ) -+#endif - - /** - * clockevents_increase_min_delta - raise minimum delta of a clock event device -diff -Nur a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c ---- a/kernel/time/posix-cpu-timers.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/time/posix-cpu-timers.c 2019-02-09 17:46:12.001297867 +0000 -@@ -830,7 +830,7 @@ - tsk_expires->virt_exp = expires; - - tsk_expires->sched_exp = check_timers_list(++timers, firing, -- tsk->se.sum_exec_runtime); -+ tsk_seruntime(tsk)); - - /* - * Check for the special case thread timers. -@@ -840,7 +840,7 @@ - unsigned long hard = task_rlimit_max(tsk, RLIMIT_RTTIME); - - 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. -@@ -852,7 +852,7 @@ - __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. - */ -@@ -1095,7 +1095,7 @@ - struct task_cputime task_sample; - - task_cputime(tsk, &task_sample.utime, &task_sample.stime); -- task_sample.sum_exec_runtime = tsk->se.sum_exec_runtime; -+ task_sample.sum_exec_runtime = tsk_seruntime(tsk); - if (task_cputime_expired(&task_sample, &tsk->cputime_expires)) - return 1; - } -diff -Nur a/kernel/time/timer.c b/kernel/time/timer.c ---- a/kernel/time/timer.c 2019-02-09 17:20:30.491821512 +0000 -+++ b/kernel/time/timer.c 2019-02-09 17:46:12.001297867 +0000 -@@ -1479,7 +1479,7 @@ - * Check, if the next hrtimer event is before the next timer wheel - * event: - */ --static u64 cmp_next_hrtimer_event(u64 basem, u64 expires) -+static u64 cmp_next_hrtimer_event(struct timer_base *base, u64 basem, u64 expires) - { - u64 nextevt = hrtimer_get_next_event(); - -@@ -1497,6 +1497,9 @@ - if (nextevt <= basem) - return basem; - -+ if (nextevt < expires && nextevt - basem <= TICK_NSEC) -+ base->is_idle = false; -+ - /* - * Round up to the next jiffie. High resolution timers are - * off, so the hrtimers are expired in the tick and we need to -@@ -1566,7 +1569,7 @@ - } - raw_spin_unlock(&base->lock); - -- return cmp_next_hrtimer_event(basem, expires); -+ return cmp_next_hrtimer_event(base, basem, expires); - } - - /** -diff -Nur a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c ---- a/kernel/trace/trace_selftest.c 2019-02-06 16:30:16.000000000 +0000 -+++ b/kernel/trace/trace_selftest.c 2019-02-09 17:46:12.001297867 +0000 -@@ -1041,10 +1041,15 @@ - { - /* Make this a -deadline thread */ - static const struct sched_attr attr = { -+#ifdef CONFIG_SCHED_MUQSS -+ /* No deadline on MuQSS, use RR */ -+ .sched_policy = SCHED_RR, -+#else - .sched_policy = SCHED_DEADLINE, - .sched_runtime = 100000ULL, - .sched_deadline = 10000000ULL, - .sched_period = 10000000ULL -+#endif - }; - struct wakeup_test_data *x = data; - |