Files
asterisk/main/lock.c
George Joseph d425971009 chan_sip: Address runaway when realtime peers subscribe to mailboxes
Users upgrading from asterisk 13.5 to a later version and who use
realtime with peers that have mailboxes were experiencing runaway
situations that manifested as a continuous stream of taskprocessor
congestion errors, memory leaks and an unresponsive chan_sip.

A related issue was that setting rtcachefriends=no NEVER worked in
asterisk 13 (since the move to stasis).  In 13.5 and earlier, when a
peer tried to register, all of the stasis threads would block and
chan_sip would again become unresponsive.  After 13.5, the runaway
would happen.

There were a number of causes...
* mwi_event_cb was (indirectly) calling build_peer even though calls to
  mwi_event_cb are often caused by build_peer.
* In an effort to prevent chan_sip from being unloaded while messages
  were still in flight, destroy_mailboxes was calling
  stasis_unsubscribe_and_join but in some cases waited forever for the
  final message.
* add_peer_mailboxes wasn't properly marking the existing mailboxes
  on a peer as "keep" so build_peer would always delete them all.
* add_peer_mwi_subs was unsubscribing existing mailbox subscriptions
  then just creating them again.

All of this was causing a flood of subscribes and unsubscribes on
multiple threads all for the same peer and mailbox.

Fixes...
* add_peer_mailboxes now marks mailboxes correctly and build_peer only
  deletes the ones that really are no longer needed by the peer.
* add_peer_mwi_subs now only adds subscriptions marked as "new" instead
  of unsubscribing and resubscribing everything.  It also adds the peer
  object's address to the mailbox instead of its name to the subscription
  userdata so mwi_event_cb doesn't have to call build_peer.

With these changes, with rtcachefriends=yes (the most common setting),
there are no leaks, locks, loops or crashes at shutdown.

rtcachefriends=no still causes leaks but at least it doesn't lock, loop
or crash.  Since making rtcachefriends=no work wasnt in scope for this
issue, further work will have to be deferred to a separate patch.

Side fixes...
 * The ast_lock_track structure had a member named "thread" which gdb
   doesn't like since it conflicts with it's "thread" command.  That
   member was renamed to "thread_id".

ASTERISK-25468 #close

Change-Id: I07519ef7f092629e1e844f855abd279d6475cdd0
2016-09-23 07:53:31 -05:00

1362 lines
36 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 1999 - 2010, Digium, Inc.
*
* Mark Spencer <markster@digium.com>
*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2. See the LICENSE file
* at the top of the source tree.
*/
/*! \file
*
* \brief General Asterisk locking.
*/
/*** MODULEINFO
<support_level>core</support_level>
***/
#include "asterisk.h"
ASTERISK_REGISTER_FILE()
#include "asterisk/utils.h"
#include "asterisk/lock.h"
/* Allow direct use of pthread_mutex_* / pthread_cond_* */
#undef pthread_mutex_init
#undef pthread_mutex_destroy
#undef pthread_mutex_lock
#undef pthread_mutex_trylock
#undef pthread_mutex_t
#undef pthread_mutex_unlock
#undef pthread_cond_init
#undef pthread_cond_signal
#undef pthread_cond_broadcast
#undef pthread_cond_destroy
#undef pthread_cond_wait
#undef pthread_cond_timedwait
#if defined(DEBUG_THREADS) && defined(HAVE_BKTR)
static void __dump_backtrace(struct ast_bt *bt, int canlog)
{
char **strings;
ssize_t i;
strings = backtrace_symbols(bt->addresses, bt->num_frames);
for (i = 0; i < bt->num_frames; i++) {
__ast_mutex_logger("%s\n", strings[i]);
}
ast_std_free(strings);
}
#endif /* defined(DEBUG_THREADS) && defined(HAVE_BKTR) */
#ifdef DEBUG_THREADS
AST_MUTEX_DEFINE_STATIC(reentrancy_lock);
static inline struct ast_lock_track *ast_get_reentrancy(struct ast_lock_track **plt)
{
pthread_mutexattr_t reentr_attr;
struct ast_lock_track *lt;
/* It's a bit painful to lock a global mutex for every access to the
* reentrancy structure, but it's necessary to ensure that we don't
* double-allocate the structure or double-initialize the reentr_mutex.
*
* If you'd like to replace this with a double-checked lock, be sure to
* properly volatile-ize everything to avoid optimizer bugs.
*
* We also have to use the underlying pthread calls for manipulating
* the mutex, because this is called from the Asterisk mutex code.
*/
pthread_mutex_lock(&reentrancy_lock.mutex);
if (*plt) {
pthread_mutex_unlock(&reentrancy_lock.mutex);
return *plt;
}
lt = *plt = ast_std_calloc(1, sizeof(*lt));
if (!lt) {
fprintf(stderr, "%s: Failed to allocate lock tracking\n", __func__);
#if defined(DO_CRASH) || defined(THREAD_CRASH)
abort();
#else
pthread_mutex_unlock(&reentrancy_lock.mutex);
return NULL;
#endif
}
pthread_mutexattr_init(&reentr_attr);
pthread_mutexattr_settype(&reentr_attr, AST_MUTEX_KIND);
pthread_mutex_init(&lt->reentr_mutex, &reentr_attr);
pthread_mutexattr_destroy(&reentr_attr);
pthread_mutex_unlock(&reentrancy_lock.mutex);
return lt;
}
static inline void delete_reentrancy_cs(struct ast_lock_track **plt)
{
struct ast_lock_track *lt;
if (*plt) {
lt = *plt;
*plt = NULL;
pthread_mutex_destroy(&lt->reentr_mutex);
ast_std_free(lt);
}
}
#endif /* DEBUG_THREADS */
int __ast_pthread_mutex_init(int tracking, const char *filename, int lineno, const char *func,
const char *mutex_name, ast_mutex_t *t)
{
int res;
pthread_mutexattr_t attr;
#ifdef DEBUG_THREADS
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
if ((t->mutex) != ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
int canlog = tracking && strcmp(filename, "logger.c");
__ast_mutex_logger("%s line %d (%s): NOTICE: mutex '%s' is already initialized.\n",
filename, lineno, func, mutex_name);
DO_THREAD_CRASH;
return EBUSY;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
t->track = NULL;
t->tracking = tracking;
#endif /* DEBUG_THREADS */
pthread_mutexattr_init(&attr);
pthread_mutexattr_settype(&attr, AST_MUTEX_KIND);
res = pthread_mutex_init(&t->mutex, &attr);
pthread_mutexattr_destroy(&attr);
return res;
}
int __ast_pthread_mutex_destroy(const char *filename, int lineno, const char *func,
const char *mutex_name, ast_mutex_t *t)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = t->track;
int canlog = t->tracking && strcmp(filename, "logger.c");
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
if ((t->mutex) == ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
/* Don't try to uninitialize an uninitialized mutex
* This may have no effect on linux
* but it always generates a core on *BSD when
* linked with libpthread.
* This is not an error condition if the mutex is created on the fly.
*/
__ast_mutex_logger("%s line %d (%s): NOTICE: mutex '%s' is uninitialized.\n",
filename, lineno, func, mutex_name);
DO_THREAD_CRASH;
res = EINVAL;
goto lt_cleanup;
}
#endif
res = pthread_mutex_trylock(&t->mutex);
switch (res) {
case 0:
pthread_mutex_unlock(&t->mutex);
break;
case EINVAL:
__ast_mutex_logger("%s line %d (%s): Error: attempt to destroy invalid mutex '%s'.\n",
filename, lineno, func, mutex_name);
break;
case EBUSY:
__ast_mutex_logger("%s line %d (%s): Error: attempt to destroy locked mutex '%s'.\n",
filename, lineno, func, mutex_name);
if (lt) {
ast_reentrancy_lock(lt);
__ast_mutex_logger("%s line %d (%s): Error: '%s' was locked here.\n",
lt->file[ROFFSET], lt->lineno[ROFFSET], lt->func[ROFFSET], mutex_name);
#ifdef HAVE_BKTR
__dump_backtrace(&lt->backtrace[ROFFSET], canlog);
#endif
ast_reentrancy_unlock(lt);
}
break;
}
#endif /* DEBUG_THREADS */
res = pthread_mutex_destroy(&t->mutex);
#ifdef DEBUG_THREADS
if (res) {
__ast_mutex_logger("%s line %d (%s): Error destroying mutex %s: %s\n",
filename, lineno, func, mutex_name, strerror(res));
}
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
lt_cleanup:
#endif
if (lt) {
ast_reentrancy_lock(lt);
lt->file[0] = filename;
lt->lineno[0] = lineno;
lt->func[0] = func;
lt->reentrancy = 0;
lt->thread_id[0] = 0;
#ifdef HAVE_BKTR
memset(&lt->backtrace[0], 0, sizeof(lt->backtrace[0]));
#endif
ast_reentrancy_unlock(lt);
delete_reentrancy_cs(&t->track);
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_pthread_mutex_lock(const char *filename, int lineno, const char *func,
const char* mutex_name, ast_mutex_t *t)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
int canlog = t->tracking && strcmp(filename, "logger.c");
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
#ifdef HAVE_BKTR
struct ast_bt tmp;
/* The implementation of backtrace() may have its own locks.
* Capture the backtrace outside of the reentrancy lock to
* avoid deadlocks. See ASTERISK-22455. */
ast_bt_get_addresses(&tmp);
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->backtrace[lt->reentrancy] = tmp;
bt = &lt->backtrace[lt->reentrancy];
}
ast_reentrancy_unlock(lt);
ast_store_lock_info(AST_MUTEX, filename, lineno, func, mutex_name, t, bt);
#else
ast_store_lock_info(AST_MUTEX, filename, lineno, func, mutex_name, t);
#endif
}
#endif /* DEBUG_THREADS */
#if defined(DETECT_DEADLOCKS) && defined(DEBUG_THREADS)
{
time_t seconds = time(NULL);
time_t wait_time, reported_wait = 0;
do {
#ifdef HAVE_MTX_PROFILE
ast_mark(mtx_prof, 1);
#endif
res = pthread_mutex_trylock(&t->mutex);
#ifdef HAVE_MTX_PROFILE
ast_mark(mtx_prof, 0);
#endif
if (res == EBUSY) {
wait_time = time(NULL) - seconds;
if (wait_time > reported_wait && (wait_time % 5) == 0) {
__ast_mutex_logger("%s line %d (%s): Deadlock? waited %d sec for mutex '%s'?\n",
filename, lineno, func, (int) wait_time, mutex_name);
if (lt) {
ast_reentrancy_lock(lt);
#ifdef HAVE_BKTR
__dump_backtrace(&lt->backtrace[lt->reentrancy], canlog);
#endif
__ast_mutex_logger("%s line %d (%s): '%s' was locked here.\n",
lt->file[ROFFSET], lt->lineno[ROFFSET],
lt->func[ROFFSET], mutex_name);
#ifdef HAVE_BKTR
__dump_backtrace(&lt->backtrace[ROFFSET], canlog);
#endif
ast_reentrancy_unlock(lt);
}
reported_wait = wait_time;
}
usleep(200);
}
} while (res == EBUSY);
}
#else /* !DETECT_DEADLOCKS || !DEBUG_THREADS */
#ifdef HAVE_MTX_PROFILE
ast_mark(mtx_prof, 1);
res = pthread_mutex_trylock(&t->mutex);
ast_mark(mtx_prof, 0);
if (res)
#endif
res = pthread_mutex_lock(&t->mutex);
#endif /* !DETECT_DEADLOCKS || !DEBUG_THREADS */
#ifdef DEBUG_THREADS
if (lt && !res) {
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->file[lt->reentrancy] = filename;
lt->lineno[lt->reentrancy] = lineno;
lt->func[lt->reentrancy] = func;
lt->thread_id[lt->reentrancy] = pthread_self();
lt->reentrancy++;
} else {
__ast_mutex_logger("%s line %d (%s): '%s' really deep reentrancy!\n",
filename, lineno, func, mutex_name);
}
ast_reentrancy_unlock(lt);
ast_mark_lock_acquired(t);
} else if (lt) {
#ifdef HAVE_BKTR
if (lt->reentrancy) {
ast_reentrancy_lock(lt);
bt = &lt->backtrace[lt->reentrancy-1];
ast_reentrancy_unlock(lt);
} else {
bt = NULL;
}
ast_remove_lock_info(t, bt);
#else
ast_remove_lock_info(t);
#endif
}
if (res) {
__ast_mutex_logger("%s line %d (%s): Error obtaining mutex: %s\n",
filename, lineno, func, strerror(res));
DO_THREAD_CRASH;
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_pthread_mutex_trylock(const char *filename, int lineno, const char *func,
const char* mutex_name, ast_mutex_t *t)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
int canlog = t->tracking && strcmp(filename, "logger.c");
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
#ifdef HAVE_BKTR
struct ast_bt tmp;
/* The implementation of backtrace() may have its own locks.
* Capture the backtrace outside of the reentrancy lock to
* avoid deadlocks. See ASTERISK-22455. */
ast_bt_get_addresses(&tmp);
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->backtrace[lt->reentrancy] = tmp;
bt = &lt->backtrace[lt->reentrancy];
}
ast_reentrancy_unlock(lt);
ast_store_lock_info(AST_MUTEX, filename, lineno, func, mutex_name, t, bt);
#else
ast_store_lock_info(AST_MUTEX, filename, lineno, func, mutex_name, t);
#endif
}
#endif /* DEBUG_THREADS */
res = pthread_mutex_trylock(&t->mutex);
#ifdef DEBUG_THREADS
if (lt && !res) {
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->file[lt->reentrancy] = filename;
lt->lineno[lt->reentrancy] = lineno;
lt->func[lt->reentrancy] = func;
lt->thread_id[lt->reentrancy] = pthread_self();
lt->reentrancy++;
} else {
__ast_mutex_logger("%s line %d (%s): '%s' really deep reentrancy!\n",
filename, lineno, func, mutex_name);
}
ast_reentrancy_unlock(lt);
ast_mark_lock_acquired(t);
} else if (lt) {
ast_mark_lock_failed(t);
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_pthread_mutex_unlock(const char *filename, int lineno, const char *func,
const char *mutex_name, ast_mutex_t *t)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
int canlog = t->tracking && strcmp(filename, "logger.c");
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
if ((t->mutex) == ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
__ast_mutex_logger("%s line %d (%s): Error: mutex '%s' is uninitialized.\n",
filename, lineno, func, mutex_name);
DO_THREAD_CRASH;
return EINVAL;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
ast_reentrancy_lock(lt);
if (lt->reentrancy && (lt->thread_id[ROFFSET] != pthread_self())) {
__ast_mutex_logger("%s line %d (%s): attempted unlock mutex '%s' without owning it!\n",
filename, lineno, func, mutex_name);
__ast_mutex_logger("%s line %d (%s): '%s' was locked here.\n",
lt->file[ROFFSET], lt->lineno[ROFFSET], lt->func[ROFFSET], mutex_name);
#ifdef HAVE_BKTR
__dump_backtrace(&lt->backtrace[ROFFSET], canlog);
#endif
DO_THREAD_CRASH;
}
if (--lt->reentrancy < 0) {
__ast_mutex_logger("%s line %d (%s): mutex '%s' freed more times than we've locked!\n",
filename, lineno, func, mutex_name);
lt->reentrancy = 0;
}
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->file[lt->reentrancy] = NULL;
lt->lineno[lt->reentrancy] = 0;
lt->func[lt->reentrancy] = NULL;
lt->thread_id[lt->reentrancy] = 0;
}
#ifdef HAVE_BKTR
if (lt->reentrancy) {
bt = &lt->backtrace[lt->reentrancy - 1];
}
#endif
ast_reentrancy_unlock(lt);
#ifdef HAVE_BKTR
ast_remove_lock_info(t, bt);
#else
ast_remove_lock_info(t);
#endif
}
#endif /* DEBUG_THREADS */
res = pthread_mutex_unlock(&t->mutex);
#ifdef DEBUG_THREADS
if (res) {
__ast_mutex_logger("%s line %d (%s): Error releasing mutex: %s\n",
filename, lineno, func, strerror(res));
DO_THREAD_CRASH;
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_cond_init(const char *filename, int lineno, const char *func,
const char *cond_name, ast_cond_t *cond, pthread_condattr_t *cond_attr)
{
return pthread_cond_init(cond, cond_attr);
}
int __ast_cond_signal(const char *filename, int lineno, const char *func,
const char *cond_name, ast_cond_t *cond)
{
return pthread_cond_signal(cond);
}
int __ast_cond_broadcast(const char *filename, int lineno, const char *func,
const char *cond_name, ast_cond_t *cond)
{
return pthread_cond_broadcast(cond);
}
int __ast_cond_destroy(const char *filename, int lineno, const char *func,
const char *cond_name, ast_cond_t *cond)
{
return pthread_cond_destroy(cond);
}
#ifdef DEBUG_THREADS
static void restore_lock_tracking(struct ast_lock_track *lt, struct ast_lock_track *lt_saved)
{
ast_reentrancy_lock(lt);
/*
* The following code must match the struct ast_lock_track
* definition with the explicit exception of the reentr_mutex
* member.
*/
memcpy(lt->file, lt_saved->file, sizeof(lt->file));
memcpy(lt->lineno, lt_saved->lineno, sizeof(lt->lineno));
lt->reentrancy = lt_saved->reentrancy;
memcpy(lt->func, lt_saved->func, sizeof(lt->func));
memcpy(lt->thread_id, lt_saved->thread_id, sizeof(lt->thread_id));
#ifdef HAVE_BKTR
memcpy(lt->backtrace, lt_saved->backtrace, sizeof(lt->backtrace));
#endif
ast_reentrancy_unlock(lt);
}
#endif /* DEBUG_THREADS */
int __ast_cond_wait(const char *filename, int lineno, const char *func,
const char *cond_name, const char *mutex_name,
ast_cond_t *cond, ast_mutex_t *t)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
struct ast_lock_track lt_orig;
int canlog = t->tracking && strcmp(filename, "logger.c");
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
if ((t->mutex) == ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
__ast_mutex_logger("%s line %d (%s): Error: mutex '%s' is uninitialized.\n",
filename, lineno, func, mutex_name);
DO_THREAD_CRASH;
return EINVAL;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
ast_reentrancy_lock(lt);
if (lt->reentrancy && (lt->thread_id[ROFFSET] != pthread_self())) {
__ast_mutex_logger("%s line %d (%s): attempted wait using mutex '%s' without owning it!\n",
filename, lineno, func, mutex_name);
__ast_mutex_logger("%s line %d (%s): '%s' was locked here.\n",
lt->file[ROFFSET], lt->lineno[ROFFSET], lt->func[ROFFSET], mutex_name);
#ifdef HAVE_BKTR
__dump_backtrace(&lt->backtrace[ROFFSET], canlog);
#endif
DO_THREAD_CRASH;
} else if (lt->reentrancy <= 0) {
__ast_mutex_logger("%s line %d (%s): attempted wait using an unlocked mutex '%s'\n",
filename, lineno, func, mutex_name);
DO_THREAD_CRASH;
}
/* Waiting on a condition completely suspends a recursive mutex,
* even if it's been recursively locked multiple times. Make a
* copy of the lock tracking, and reset reentrancy to zero */
lt_orig = *lt;
lt->reentrancy = 0;
ast_reentrancy_unlock(lt);
ast_suspend_lock_info(t);
}
#endif /* DEBUG_THREADS */
res = pthread_cond_wait(cond, &t->mutex);
#ifdef DEBUG_THREADS
if (res) {
__ast_mutex_logger("%s line %d (%s): Error waiting on condition mutex '%s'\n",
filename, lineno, func, strerror(res));
DO_THREAD_CRASH;
} else if (lt) {
restore_lock_tracking(lt, &lt_orig);
ast_restore_lock_info(t);
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_cond_timedwait(const char *filename, int lineno, const char *func,
const char *cond_name, const char *mutex_name, ast_cond_t *cond,
ast_mutex_t *t, const struct timespec *abstime)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
struct ast_lock_track lt_orig;
int canlog = t->tracking && strcmp(filename, "logger.c");
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
if ((t->mutex) == ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
__ast_mutex_logger("%s line %d (%s): Error: mutex '%s' is uninitialized.\n",
filename, lineno, func, mutex_name);
DO_THREAD_CRASH;
return EINVAL;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
ast_reentrancy_lock(lt);
if (lt->reentrancy && (lt->thread_id[ROFFSET] != pthread_self())) {
__ast_mutex_logger("%s line %d (%s): attempted wait using mutex '%s' without owning it!\n",
filename, lineno, func, mutex_name);
__ast_mutex_logger("%s line %d (%s): '%s' was locked here.\n",
lt->file[ROFFSET], lt->lineno[ROFFSET], lt->func[ROFFSET], mutex_name);
#ifdef HAVE_BKTR
__dump_backtrace(&lt->backtrace[ROFFSET], canlog);
#endif
DO_THREAD_CRASH;
} else if (lt->reentrancy <= 0) {
__ast_mutex_logger("%s line %d (%s): attempted wait using an unlocked mutex '%s'\n",
filename, lineno, func, mutex_name);
DO_THREAD_CRASH;
}
/* Waiting on a condition completely suspends a recursive mutex,
* even if it's been recursively locked multiple times. Make a
* copy of the lock tracking, and reset reentrancy to zero */
lt_orig = *lt;
lt->reentrancy = 0;
ast_reentrancy_unlock(lt);
ast_suspend_lock_info(t);
}
#endif /* DEBUG_THREADS */
res = pthread_cond_timedwait(cond, &t->mutex, abstime);
#ifdef DEBUG_THREADS
if (res && (res != ETIMEDOUT)) {
__ast_mutex_logger("%s line %d (%s): Error waiting on condition mutex '%s'\n",
filename, lineno, func, strerror(res));
DO_THREAD_CRASH;
} else if (lt) {
restore_lock_tracking(lt, &lt_orig);
ast_restore_lock_info(t);
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_rwlock_init(int tracking, const char *filename, int lineno, const char *func, const char *rwlock_name, ast_rwlock_t *t)
{
int res;
pthread_rwlockattr_t attr;
#ifdef DEBUG_THREADS
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
if (t->lock != ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
int canlog = tracking && strcmp(filename, "logger.c");
__ast_mutex_logger("%s line %d (%s): Warning: rwlock '%s' is already initialized.\n",
filename, lineno, func, rwlock_name);
DO_THREAD_CRASH;
return EBUSY;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
t->track = NULL;
t->tracking = tracking;
#endif /* DEBUG_THREADS */
pthread_rwlockattr_init(&attr);
#ifdef HAVE_PTHREAD_RWLOCK_PREFER_WRITER_NP
pthread_rwlockattr_setkind_np(&attr, PTHREAD_RWLOCK_PREFER_WRITER_NP);
#endif
res = pthread_rwlock_init(&t->lock, &attr);
pthread_rwlockattr_destroy(&attr);
return res;
}
int __ast_rwlock_destroy(const char *filename, int lineno, const char *func, const char *rwlock_name, ast_rwlock_t *t)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = t->track;
int canlog = t->tracking && strcmp(filename, "logger.c");
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
if (t->lock == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
__ast_mutex_logger("%s line %d (%s): Warning: rwlock '%s' is uninitialized.\n",
filename, lineno, func, rwlock_name);
DO_THREAD_CRASH;
res = EINVAL;
goto lt_cleanup;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
#endif /* DEBUG_THREADS */
res = pthread_rwlock_destroy(&t->lock);
#ifdef DEBUG_THREADS
if (res) {
__ast_mutex_logger("%s line %d (%s): Error destroying rwlock %s: %s\n",
filename, lineno, func, rwlock_name, strerror(res));
}
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
lt_cleanup:
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (lt) {
ast_reentrancy_lock(lt);
lt->file[0] = filename;
lt->lineno[0] = lineno;
lt->func[0] = func;
lt->reentrancy = 0;
lt->thread_id[0] = 0;
#ifdef HAVE_BKTR
memset(&lt->backtrace[0], 0, sizeof(lt->backtrace[0]));
#endif
ast_reentrancy_unlock(lt);
delete_reentrancy_cs(&t->track);
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_rwlock_unlock(const char *filename, int line, const char *func, ast_rwlock_t *t, const char *name)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
int canlog = t->tracking && strcmp(filename, "logger.c");
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
int lock_found = 0;
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
if ((t->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
__ast_mutex_logger("%s line %d (%s): Warning: rwlock '%s' is uninitialized.\n",
filename, line, func, name);
DO_THREAD_CRASH;
return EINVAL;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
ast_reentrancy_lock(lt);
if (lt->reentrancy) {
int i;
pthread_t self = pthread_self();
for (i = lt->reentrancy - 1; i >= 0; --i) {
if (lt->thread_id[i] == self) {
lock_found = 1;
if (i != lt->reentrancy - 1) {
lt->file[i] = lt->file[lt->reentrancy - 1];
lt->lineno[i] = lt->lineno[lt->reentrancy - 1];
lt->func[i] = lt->func[lt->reentrancy - 1];
lt->thread_id[i] = lt->thread_id[lt->reentrancy - 1];
}
#ifdef HAVE_BKTR
bt = &lt->backtrace[i];
#endif
lt->file[lt->reentrancy - 1] = NULL;
lt->lineno[lt->reentrancy - 1] = 0;
lt->func[lt->reentrancy - 1] = NULL;
lt->thread_id[lt->reentrancy - 1] = AST_PTHREADT_NULL;
break;
}
}
}
if (lock_found && --lt->reentrancy < 0) {
__ast_mutex_logger("%s line %d (%s): rwlock '%s' freed more times than we've locked!\n",
filename, line, func, name);
lt->reentrancy = 0;
}
ast_reentrancy_unlock(lt);
#ifdef HAVE_BKTR
ast_remove_lock_info(t, bt);
#else
ast_remove_lock_info(t);
#endif
}
#endif /* DEBUG_THREADS */
res = pthread_rwlock_unlock(&t->lock);
#ifdef DEBUG_THREADS
if (res) {
__ast_mutex_logger("%s line %d (%s): Error releasing rwlock: %s\n",
filename, line, func, strerror(res));
DO_THREAD_CRASH;
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_rwlock_rdlock(const char *filename, int line, const char *func, ast_rwlock_t *t, const char *name)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
int canlog = t->tracking && strcmp(filename, "logger.c");
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
#ifdef HAVE_BKTR
struct ast_bt tmp;
/* The implementation of backtrace() may have its own locks.
* Capture the backtrace outside of the reentrancy lock to
* avoid deadlocks. See ASTERISK-22455. */
ast_bt_get_addresses(&tmp);
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->backtrace[lt->reentrancy] = tmp;
bt = &lt->backtrace[lt->reentrancy];
}
ast_reentrancy_unlock(lt);
ast_store_lock_info(AST_RDLOCK, filename, line, func, name, t, bt);
#else
ast_store_lock_info(AST_RDLOCK, filename, line, func, name, t);
#endif
}
#endif /* DEBUG_THREADS */
#if defined(DETECT_DEADLOCKS) && defined(DEBUG_THREADS)
{
time_t seconds = time(NULL);
time_t wait_time, reported_wait = 0;
do {
res = pthread_rwlock_tryrdlock(&t->lock);
if (res == EBUSY) {
wait_time = time(NULL) - seconds;
if (wait_time > reported_wait && (wait_time % 5) == 0) {
__ast_mutex_logger("%s line %d (%s): Deadlock? waited %d sec for readlock '%s'?\n",
filename, line, func, (int)wait_time, name);
if (lt) {
ast_reentrancy_lock(lt);
#ifdef HAVE_BKTR
__dump_backtrace(&lt->backtrace[lt->reentrancy], canlog);
#endif
__ast_mutex_logger("%s line %d (%s): '%s' was locked here.\n",
lt->file[lt->reentrancy-1], lt->lineno[lt->reentrancy-1],
lt->func[lt->reentrancy-1], name);
#ifdef HAVE_BKTR
__dump_backtrace(&lt->backtrace[lt->reentrancy-1], canlog);
#endif
ast_reentrancy_unlock(lt);
}
reported_wait = wait_time;
}
usleep(200);
}
} while (res == EBUSY);
}
#else /* !DETECT_DEADLOCKS || !DEBUG_THREADS */
res = pthread_rwlock_rdlock(&t->lock);
#endif /* !DETECT_DEADLOCKS || !DEBUG_THREADS */
#ifdef DEBUG_THREADS
if (!res && lt) {
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->file[lt->reentrancy] = filename;
lt->lineno[lt->reentrancy] = line;
lt->func[lt->reentrancy] = func;
lt->thread_id[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
ast_mark_lock_acquired(t);
} else if (lt) {
#ifdef HAVE_BKTR
if (lt->reentrancy) {
ast_reentrancy_lock(lt);
bt = &lt->backtrace[lt->reentrancy-1];
ast_reentrancy_unlock(lt);
} else {
bt = NULL;
}
ast_remove_lock_info(t, bt);
#else
ast_remove_lock_info(t);
#endif
}
if (res) {
__ast_mutex_logger("%s line %d (%s): Error obtaining read lock: %s\n",
filename, line, func, strerror(res));
DO_THREAD_CRASH;
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_rwlock_wrlock(const char *filename, int line, const char *func, ast_rwlock_t *t, const char *name)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
int canlog = t->tracking && strcmp(filename, "logger.c");
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
#ifdef HAVE_BKTR
struct ast_bt tmp;
/* The implementation of backtrace() may have its own locks.
* Capture the backtrace outside of the reentrancy lock to
* avoid deadlocks. See ASTERISK-22455. */
ast_bt_get_addresses(&tmp);
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->backtrace[lt->reentrancy] = tmp;
bt = &lt->backtrace[lt->reentrancy];
}
ast_reentrancy_unlock(lt);
ast_store_lock_info(AST_WRLOCK, filename, line, func, name, t, bt);
#else
ast_store_lock_info(AST_WRLOCK, filename, line, func, name, t);
#endif
}
#endif /* DEBUG_THREADS */
#if defined(DETECT_DEADLOCKS) && defined(DEBUG_THREADS)
{
time_t seconds = time(NULL);
time_t wait_time, reported_wait = 0;
do {
res = pthread_rwlock_trywrlock(&t->lock);
if (res == EBUSY) {
wait_time = time(NULL) - seconds;
if (wait_time > reported_wait && (wait_time % 5) == 0) {
__ast_mutex_logger("%s line %d (%s): Deadlock? waited %d sec for writelock '%s'?\n",
filename, line, func, (int)wait_time, name);
if (lt) {
ast_reentrancy_lock(lt);
#ifdef HAVE_BKTR
__dump_backtrace(&lt->backtrace[lt->reentrancy], canlog);
#endif
__ast_mutex_logger("%s line %d (%s): '%s' was locked here.\n",
lt->file[lt->reentrancy-1], lt->lineno[lt->reentrancy-1],
lt->func[lt->reentrancy-1], name);
#ifdef HAVE_BKTR
__dump_backtrace(&lt->backtrace[lt->reentrancy-1], canlog);
#endif
ast_reentrancy_unlock(lt);
}
reported_wait = wait_time;
}
usleep(200);
}
} while (res == EBUSY);
}
#else /* !DETECT_DEADLOCKS || !DEBUG_THREADS */
res = pthread_rwlock_wrlock(&t->lock);
#endif /* !DETECT_DEADLOCKS || !DEBUG_THREADS */
#ifdef DEBUG_THREADS
if (!res && lt) {
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->file[lt->reentrancy] = filename;
lt->lineno[lt->reentrancy] = line;
lt->func[lt->reentrancy] = func;
lt->thread_id[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
ast_mark_lock_acquired(t);
} else if (lt) {
#ifdef HAVE_BKTR
if (lt->reentrancy) {
ast_reentrancy_lock(lt);
bt = &lt->backtrace[lt->reentrancy-1];
ast_reentrancy_unlock(lt);
} else {
bt = NULL;
}
ast_remove_lock_info(t, bt);
#else
ast_remove_lock_info(t);
#endif
}
if (res) {
__ast_mutex_logger("%s line %d (%s): Error obtaining write lock: %s\n",
filename, line, func, strerror(res));
DO_THREAD_CRASH;
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_rwlock_timedrdlock(const char *filename, int line, const char *func, ast_rwlock_t *t, const char *name,
const struct timespec *abs_timeout)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
int canlog = t->tracking && strcmp(filename, "logger.c");
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
#ifdef HAVE_BKTR
struct ast_bt tmp;
/* The implementation of backtrace() may have its own locks.
* Capture the backtrace outside of the reentrancy lock to
* avoid deadlocks. See ASTERISK-22455. */
ast_bt_get_addresses(&tmp);
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->backtrace[lt->reentrancy] = tmp;
bt = &lt->backtrace[lt->reentrancy];
}
ast_reentrancy_unlock(lt);
ast_store_lock_info(AST_WRLOCK, filename, line, func, name, t, bt);
#else
ast_store_lock_info(AST_WRLOCK, filename, line, func, name, t);
#endif
}
#endif /* DEBUG_THREADS */
#ifdef HAVE_PTHREAD_RWLOCK_TIMEDWRLOCK
res = pthread_rwlock_timedrdlock(&t->lock, abs_timeout);
#else
do {
struct timeval _now;
for (;;) {
if (!(res = pthread_rwlock_tryrdlock(&t->lock))) {
break;
}
_now = ast_tvnow();
if (_now.tv_sec > abs_timeout->tv_sec || (_now.tv_sec == abs_timeout->tv_sec && _now.tv_usec * 1000 > abs_timeout->tv_nsec)) {
break;
}
usleep(1);
}
} while (0);
#endif
#ifdef DEBUG_THREADS
if (!res && lt) {
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->file[lt->reentrancy] = filename;
lt->lineno[lt->reentrancy] = line;
lt->func[lt->reentrancy] = func;
lt->thread_id[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
ast_mark_lock_acquired(t);
} else if (lt) {
#ifdef HAVE_BKTR
if (lt->reentrancy) {
ast_reentrancy_lock(lt);
bt = &lt->backtrace[lt->reentrancy-1];
ast_reentrancy_unlock(lt);
} else {
bt = NULL;
}
ast_remove_lock_info(t, bt);
#else
ast_remove_lock_info(t);
#endif
}
if (res) {
__ast_mutex_logger("%s line %d (%s): Error obtaining read lock: %s\n",
filename, line, func, strerror(res));
DO_THREAD_CRASH;
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_rwlock_timedwrlock(const char *filename, int line, const char *func, ast_rwlock_t *t, const char *name,
const struct timespec *abs_timeout)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
int canlog = t->tracking && strcmp(filename, "logger.c");
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
#ifdef HAVE_BKTR
struct ast_bt tmp;
/* The implementation of backtrace() may have its own locks.
* Capture the backtrace outside of the reentrancy lock to
* avoid deadlocks. See ASTERISK-22455. */
ast_bt_get_addresses(&tmp);
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->backtrace[lt->reentrancy] = tmp;
bt = &lt->backtrace[lt->reentrancy];
}
ast_reentrancy_unlock(lt);
ast_store_lock_info(AST_WRLOCK, filename, line, func, name, t, bt);
#else
ast_store_lock_info(AST_WRLOCK, filename, line, func, name, t);
#endif
}
#endif /* DEBUG_THREADS */
#ifdef HAVE_PTHREAD_RWLOCK_TIMEDWRLOCK
res = pthread_rwlock_timedwrlock(&t->lock, abs_timeout);
#else
do {
struct timeval _now;
for (;;) {
if (!(res = pthread_rwlock_trywrlock(&t->lock))) {
break;
}
_now = ast_tvnow();
if (_now.tv_sec > abs_timeout->tv_sec || (_now.tv_sec == abs_timeout->tv_sec && _now.tv_usec * 1000 > abs_timeout->tv_nsec)) {
break;
}
usleep(1);
}
} while (0);
#endif
#ifdef DEBUG_THREADS
if (!res && lt) {
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->file[lt->reentrancy] = filename;
lt->lineno[lt->reentrancy] = line;
lt->func[lt->reentrancy] = func;
lt->thread_id[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
ast_mark_lock_acquired(t);
} else if (lt) {
#ifdef HAVE_BKTR
if (lt->reentrancy) {
ast_reentrancy_lock(lt);
bt = &lt->backtrace[lt->reentrancy-1];
ast_reentrancy_unlock(lt);
} else {
bt = NULL;
}
ast_remove_lock_info(t, bt);
#else
ast_remove_lock_info(t);
#endif
}
if (res) {
__ast_mutex_logger("%s line %d (%s): Error obtaining read lock: %s\n",
filename, line, func, strerror(res));
DO_THREAD_CRASH;
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_rwlock_tryrdlock(const char *filename, int line, const char *func, ast_rwlock_t *t, const char *name)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
#ifdef HAVE_BKTR
struct ast_bt tmp;
/* The implementation of backtrace() may have its own locks.
* Capture the backtrace outside of the reentrancy lock to
* avoid deadlocks. See ASTERISK-22455. */
ast_bt_get_addresses(&tmp);
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->backtrace[lt->reentrancy] = tmp;
bt = &lt->backtrace[lt->reentrancy];
}
ast_reentrancy_unlock(lt);
ast_store_lock_info(AST_RDLOCK, filename, line, func, name, t, bt);
#else
ast_store_lock_info(AST_RDLOCK, filename, line, func, name, t);
#endif
}
#endif /* DEBUG_THREADS */
res = pthread_rwlock_tryrdlock(&t->lock);
#ifdef DEBUG_THREADS
if (!res && lt) {
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->file[lt->reentrancy] = filename;
lt->lineno[lt->reentrancy] = line;
lt->func[lt->reentrancy] = func;
lt->thread_id[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
ast_mark_lock_acquired(t);
} else if (lt) {
ast_mark_lock_failed(t);
}
#endif /* DEBUG_THREADS */
return res;
}
int __ast_rwlock_trywrlock(const char *filename, int line, const char *func, ast_rwlock_t *t, const char *name)
{
int res;
#ifdef DEBUG_THREADS
struct ast_lock_track *lt = NULL;
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
if (t->tracking) {
lt = ast_get_reentrancy(&t->track);
}
if (lt) {
#ifdef HAVE_BKTR
struct ast_bt tmp;
/* The implementation of backtrace() may have its own locks.
* Capture the backtrace outside of the reentrancy lock to
* avoid deadlocks. See ASTERISK-22455. */
ast_bt_get_addresses(&tmp);
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->backtrace[lt->reentrancy] = tmp;
bt = &lt->backtrace[lt->reentrancy];
}
ast_reentrancy_unlock(lt);
ast_store_lock_info(AST_WRLOCK, filename, line, func, name, t, bt);
#else
ast_store_lock_info(AST_WRLOCK, filename, line, func, name, t);
#endif
}
#endif /* DEBUG_THREADS */
res = pthread_rwlock_trywrlock(&t->lock);
#ifdef DEBUG_THREADS
if (!res && lt) {
ast_reentrancy_lock(lt);
if (lt->reentrancy < AST_MAX_REENTRANCY) {
lt->file[lt->reentrancy] = filename;
lt->lineno[lt->reentrancy] = line;
lt->func[lt->reentrancy] = func;
lt->thread_id[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
ast_mark_lock_acquired(t);
} else if (lt) {
ast_mark_lock_failed(t);
}
#endif /* DEBUG_THREADS */
return res;
}