diff options
Diffstat (limited to 'net-misc/asterisk/files/asterisk-13.38.2-r3-func_lock-fix-races.patch')
-rw-r--r-- | net-misc/asterisk/files/asterisk-13.38.2-r3-func_lock-fix-races.patch | 421 |
1 files changed, 0 insertions, 421 deletions
diff --git a/net-misc/asterisk/files/asterisk-13.38.2-r3-func_lock-fix-races.patch b/net-misc/asterisk/files/asterisk-13.38.2-r3-func_lock-fix-races.patch deleted file mode 100644 index 3d3c7b101d47..000000000000 --- a/net-misc/asterisk/files/asterisk-13.38.2-r3-func_lock-fix-races.patch +++ /dev/null @@ -1,421 +0,0 @@ -From b35211fd58afcf430a0d95a243dc7a086d72b2b8 Mon Sep 17 00:00:00 2001 -From: Jaco Kroon <jaco@uls.co.za> -Date: Fri, 21 May 2021 20:11:59 +0200 -Subject: [PATCH] Replacement patch for v13. - -Change-Id: I30236d7d7229f317c681fb7c6d7944d6108acd08 ---- - funcs/func_lock.c | 234 +++++++++++++++++++++++++--------------------- - 1 file changed, 126 insertions(+), 108 deletions(-) - -diff --git a/funcs/func_lock.c b/funcs/func_lock.c -index a006a574eb..c472504f52 100644 ---- a/funcs/func_lock.c -+++ b/funcs/func_lock.c -@@ -44,6 +44,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$") - #include "asterisk/linkedlists.h" - #include "asterisk/astobj2.h" - #include "asterisk/utils.h" -+#include "asterisk/cli.h" - - /*** DOCUMENTATION - <function name="LOCK" language="en_US"> -@@ -112,7 +113,6 @@ static AST_LIST_HEAD_STATIC(locklist, lock_frame); - static void lock_free(void *data); - static void lock_fixup(void *data, struct ast_channel *oldchan, struct ast_channel *newchan); - static int unloading = 0; --static pthread_t broker_tid = AST_PTHREADT_NULL; - - static const struct ast_datastore_info lock_info = { - .type = "MUTEX", -@@ -126,8 +126,8 @@ struct lock_frame { - ast_cond_t cond; - /*! count is needed so if a recursive mutex exits early, we know how many times to unlock it. */ - unsigned int count; -- /*! Container of requesters for the named lock */ -- struct ao2_container *requesters; -+ /*! Count of waiting of requesters for the named lock */ -+ unsigned int requesters; - /*! who owns us */ - struct ast_channel *owner; - /*! name of the lock */ -@@ -149,14 +149,19 @@ static void lock_free(void *data) - while ((clframe = AST_LIST_REMOVE_HEAD(oldlist, list))) { - /* Only unlock if we own the lock */ - if (clframe->channel == clframe->lock_frame->owner) { -+ ast_mutex_lock(&clframe->lock_frame->mutex); - clframe->lock_frame->count = 0; - clframe->lock_frame->owner = NULL; -+ ast_cond_signal(&clframe->lock_frame->cond); -+ ast_mutex_unlock(&clframe->lock_frame->mutex); - } - ast_free(clframe); - } - AST_LIST_UNLOCK(oldlist); - AST_LIST_HEAD_DESTROY(oldlist); - ast_free(oldlist); -+ -+ ast_module_unref(ast_module_info->self); - } - - static void lock_fixup(void *data, struct ast_channel *oldchan, struct ast_channel *newchan) -@@ -175,54 +180,11 @@ static void lock_fixup(void *data, struct ast_channel *oldchan, struct ast_chann - if (clframe->lock_frame->owner == oldchan) { - clframe->lock_frame->owner = newchan; - } -- /* We don't move requesters, because the thread stack is different */ - clframe->channel = newchan; - } - AST_LIST_UNLOCK(list); - } - --static void *lock_broker(void *unused) --{ -- struct lock_frame *frame; -- struct timespec forever = { 1000000, 0 }; -- for (;;) { -- int found_requester = 0; -- -- /* Test for cancel outside of the lock */ -- pthread_testcancel(); -- AST_LIST_LOCK(&locklist); -- -- AST_LIST_TRAVERSE(&locklist, frame, entries) { -- if (ao2_container_count(frame->requesters)) { -- found_requester++; -- ast_mutex_lock(&frame->mutex); -- if (!frame->owner) { -- ast_cond_signal(&frame->cond); -- } -- ast_mutex_unlock(&frame->mutex); -- } -- } -- -- AST_LIST_UNLOCK(&locklist); -- pthread_testcancel(); -- -- /* If there are no requesters, then wait for a signal */ -- if (!found_requester) { -- nanosleep(&forever, NULL); -- } else { -- sched_yield(); -- } -- } -- /* Not reached */ -- return NULL; --} -- --static int ast_channel_cmp_cb(void *obj, void *arg, int flags) --{ -- struct ast_channel *chan = obj, *cmp_args = arg; -- return strcasecmp(ast_channel_name(chan), ast_channel_name(cmp_args)) ? 0 : CMP_MATCH; --} -- - static int get_lock(struct ast_channel *chan, char *lockname, int trylock) - { - struct ast_datastore *lock_store = ast_channel_datastore_find(chan, &lock_info, NULL); -@@ -234,7 +196,12 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock) - struct timeval now; - - if (!lock_store) { -- ast_debug(1, "Channel %s has no lock datastore, so we're allocating one.\n", ast_channel_name(chan)); -+ if (unloading) { -+ ast_log(LOG_ERROR, "%sLOCK has no datastore and func_lock is unloading, failing.\n", -+ trylock ? "TRY" : ""); -+ return -1; -+ } -+ - lock_store = ast_datastore_alloc(&lock_info, NULL); - if (!lock_store) { - ast_log(LOG_ERROR, "Unable to allocate new datastore. No locks will be obtained.\n"); -@@ -253,6 +220,9 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock) - lock_store->data = list; - AST_LIST_HEAD_INIT(list); - ast_channel_datastore_add(chan, lock_store); -+ -+ /* We cannot unload until this channel has released the lock_store */ -+ ast_module_ref(ast_module_info->self); - } else - list = lock_store->data; - -@@ -266,6 +236,9 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock) - - if (!current) { - if (unloading) { -+ ast_log(LOG_ERROR, -+ "Lock doesn't exist whilst unloading. %sLOCK will fail.\n", -+ trylock ? "TRY" : ""); - /* Don't bother */ - AST_LIST_UNLOCK(&locklist); - return -1; -@@ -292,17 +265,12 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock) - AST_LIST_UNLOCK(&locklist); - return -1; - } -- current->requesters = ao2_container_alloc_list(AO2_ALLOC_OPT_LOCK_MUTEX, 0, -- NULL, ast_channel_cmp_cb); -- if (!current->requesters) { -- ast_mutex_destroy(¤t->mutex); -- ast_cond_destroy(¤t->cond); -- ast_free(current); -- AST_LIST_UNLOCK(&locklist); -- return -1; -- } - AST_LIST_INSERT_TAIL(&locklist, current, entries); - } -+ /* Add to requester list */ -+ ast_mutex_lock(¤t->mutex); -+ current->requesters++; -+ ast_mutex_unlock(¤t->mutex); - AST_LIST_UNLOCK(&locklist); - - /* Found lock or created one - now find or create the corresponding link in the channel */ -@@ -315,7 +283,13 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock) - - if (!clframe) { - if (unloading) { -+ ast_log(LOG_ERROR, -+ "Busy unloading. %sLOCK will fail.\n", -+ trylock ? "TRY" : ""); - /* Don't bother */ -+ ast_mutex_lock(¤t->mutex); -+ current->requesters--; -+ ast_mutex_unlock(¤t->mutex); - AST_LIST_UNLOCK(list); - return -1; - } -@@ -324,6 +298,9 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock) - ast_log(LOG_ERROR, - "Unable to allocate channel lock frame. %sLOCK will fail.\n", - trylock ? "TRY" : ""); -+ ast_mutex_lock(¤t->mutex); -+ current->requesters--; -+ ast_mutex_unlock(¤t->mutex); - AST_LIST_UNLOCK(list); - return -1; - } -@@ -339,44 +316,44 @@ static int get_lock(struct ast_channel *chan, char *lockname, int trylock) - * the same amount, before we'll release this one. - */ - if (current->owner == chan) { -+ /* We're not a requester, we already have it */ -+ ast_mutex_lock(¤t->mutex); -+ current->requesters--; -+ ast_mutex_unlock(¤t->mutex); - current->count++; - return 0; - } - -- /* Okay, we have both frames, so now we need to try to lock. -- * -- * Locking order: always lock locklist first. We need the -- * locklist lock because the broker thread counts whether -- * there are requesters with the locklist lock held, and we -- * need to hold it, so that when we send our signal, below, -- * to wake up the broker thread, it definitely will see that -- * a requester exists at that point in time. Otherwise, we -- * could add to the requesters after it has already seen that -- * that lock is unoccupied and wait forever for another signal. -- */ -- AST_LIST_LOCK(&locklist); -- ast_mutex_lock(¤t->mutex); -- /* Add to requester list */ -- ao2_link(current->requesters, chan); -- pthread_kill(broker_tid, SIGURG); -- AST_LIST_UNLOCK(&locklist); -- - /* Wait up to three seconds from now for LOCK. */ - now = ast_tvnow(); - timeout.tv_sec = now.tv_sec + 3; - timeout.tv_nsec = now.tv_usec * 1000; - -- if (!current->owner -- || (!trylock -- && !(res = ast_cond_timedwait(¤t->cond, ¤t->mutex, &timeout)))) { -- res = 0; -+ ast_mutex_lock(¤t->mutex); -+ -+ res = 0; -+ while (!trylock && !res && current->owner) { -+ res = ast_cond_timedwait(¤t->cond, ¤t->mutex, &timeout); -+ } -+ if (current->owner) { -+ ast_log(LOG_ERROR, "%sLOCK failed to obtain lock %s.\n", trylock ? "TRY" : "", -+ lockname); -+ /* timeout; -+ * trylock; or -+ * cond_timedwait failed. -+ * -+ * either way, we fail to obtain the lock. -+ */ -+ res = -1; -+ } else { - current->owner = chan; - current->count++; -- } else { -- res = -1; -+ res = 0; - } - /* Remove from requester list */ -- ao2_unlink(current->requesters, chan); -+ current->requesters--; -+ if (res && unloading) -+ ast_cond_signal(¤t->cond); - ast_mutex_unlock(¤t->mutex); - - return res; -@@ -400,7 +377,7 @@ static int unlock_read(struct ast_channel *chan, const char *cmd, char *data, ch - } - - if (!(list = lock_store->data)) { -- ast_debug(1, "This should NEVER happen\n"); -+ ast_log(LOG_ERROR, "Datastore's data member is NULL ... this should be impossible."); - ast_copy_string(buf, "0", len); - return 0; - } -@@ -419,12 +396,17 @@ static int unlock_read(struct ast_channel *chan, const char *cmd, char *data, ch - - if (!clframe) { - /* We didn't have this lock in the first place */ -+ ast_log(LOG_WARNING, "Attempting to UNLOCK(%s) - a lock this channel never owned.\n", -+ data); - ast_copy_string(buf, "0", len); - return 0; - } - - if (--clframe->lock_frame->count == 0) { -+ ast_mutex_lock(&clframe->lock_frame->mutex); - clframe->lock_frame->owner = NULL; -+ ast_cond_signal(&clframe->lock_frame->cond); -+ ast_mutex_unlock(&clframe->lock_frame->mutex); - } - - ast_copy_string(buf, "1", len); -@@ -455,6 +437,37 @@ static int trylock_read(struct ast_channel *chan, const char *cmd, char *data, c - return 0; - } - -+static char *handle_cli_locks_show(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a) -+{ -+ int c = 0; -+ struct lock_frame* current; -+ switch (cmd) { -+ case CLI_INIT: -+ e->command = "locks show"; -+ e->usage = -+ "Usage: locks show\n" -+ " List all locks known to func_lock, along with their current status.\n"; -+ return NULL; -+ case CLI_GENERATE: -+ return NULL; -+ } -+ -+ ast_cli(a->fd, "func_lock locks:\n"); -+ ast_cli(a->fd, "%-40s Requesters Owner\n", "Name"); -+ AST_LIST_LOCK(&locklist); -+ AST_LIST_TRAVERSE(&locklist, current, entries) { -+ ast_mutex_lock(¤t->mutex); -+ ast_cli(a->fd, "%-40s %-10d %s\n", current->name, current->requesters, -+ current->owner ? ast_channel_name(current->owner) : "(unlocked)"); -+ ast_mutex_unlock(¤t->mutex); -+ c++; -+ } -+ AST_LIST_UNLOCK(&locklist); -+ ast_cli(a->fd, "%d total locks listed.\n", c); -+ -+ return 0; -+} -+ - static struct ast_custom_function lock_function = { - .name = "LOCK", - .read = lock_read, -@@ -473,6 +486,8 @@ static struct ast_custom_function unlock_function = { - .read_max = 2, - }; - -+static struct ast_cli_entry cli_locks_show = AST_CLI_DEFINE(handle_cli_locks_show, "List func_lock locks."); -+ - static int unload_module(void) - { - struct lock_frame *current; -@@ -480,34 +495,43 @@ static int unload_module(void) - /* Module flag */ - unloading = 1; - -+ /* Make it impossible for new requesters to be added -+ * NOTE: channels could already be in get_lock() */ -+ ast_custom_function_unregister(&lock_function); -+ ast_custom_function_unregister(&trylock_function); -+ -+ ast_cli_unregister(&cli_locks_show); -+ - AST_LIST_LOCK(&locklist); - while ((current = AST_LIST_REMOVE_HEAD(&locklist, entries))) { -- /* If any locks are currently in use, then we cannot unload this module */ -- if (current->owner || ao2_container_count(current->requesters)) { -- /* Put it back */ -- AST_LIST_INSERT_HEAD(&locklist, current, entries); -- AST_LIST_UNLOCK(&locklist); -- unloading = 0; -- return -1; -+ int warned = 0; -+ ast_mutex_lock(¤t->mutex); -+ while (current->owner || current->requesters) { -+ if (!warned) { -+ ast_log(LOG_WARNING, "Waiting for %d requesters for %s lock %s.\n", -+ current->requesters, current->owner ? "locked" : "unlocked", -+ current->name); -+ warned = 1; -+ } -+ /* either the mutex is locked, or other parties are currently in get_lock, -+ * we need to wait for all of those to clear first */ -+ ast_cond_wait(¤t->cond, ¤t->mutex); - } -+ ast_mutex_unlock(¤t->mutex); -+ /* At this point we know: -+ * 1. the lock has been released, -+ * 2. there are no requesters (nor should any be able to sneak in). -+ */ - ast_mutex_destroy(¤t->mutex); -- ao2_ref(current->requesters, -1); -+ ast_cond_destroy(¤t->cond); - ast_free(current); - } -+ AST_LIST_UNLOCK(&locklist); -+ AST_LIST_HEAD_DESTROY(&locklist); - -- /* No locks left, unregister functions */ -- ast_custom_function_unregister(&lock_function); -- ast_custom_function_unregister(&trylock_function); -+ /* At this point we can safely stop access to UNLOCK */ - ast_custom_function_unregister(&unlock_function); - -- if (broker_tid != AST_PTHREADT_NULL) { -- pthread_cancel(broker_tid); -- pthread_kill(broker_tid, SIGURG); -- pthread_join(broker_tid, NULL); -- } -- -- AST_LIST_UNLOCK(&locklist); -- - return 0; - } - -@@ -516,13 +540,7 @@ static int load_module(void) - int res = ast_custom_function_register_escalating(&lock_function, AST_CFE_READ); - res |= ast_custom_function_register_escalating(&trylock_function, AST_CFE_READ); - res |= ast_custom_function_register_escalating(&unlock_function, AST_CFE_READ); -- -- if (ast_pthread_create_background(&broker_tid, NULL, lock_broker, NULL)) { -- ast_log(LOG_ERROR, "Failed to start lock broker thread. Unloading func_lock module.\n"); -- broker_tid = AST_PTHREADT_NULL; -- unload_module(); -- return AST_MODULE_LOAD_DECLINE; -- } -+ res |= ast_cli_register(&cli_locks_show); - - return res; - } --- -2.26.3 - |