asterisk/main/lock.c
David M. Lee c2e6e1ef49 Fix DEBUG_THREADS when lock is acquired in __constructor__
This patch fixes some long-standing bugs in debug threads that were
exacerbated with recent Optional API work in Asterisk 12.

With debug threads enabled, on some systems, there's a lock ordering
problem between our mutex and glibc's mutex protecting its module list
(Ubuntu Lucid, glibc 2.11.1 in this instance). In one thread, the module
list will be locked before acquiring our mutex. In another thread, our
mutex will be locked before locking the module list (which happens in
the depths of calling backtrace()).

This patch fixes this issue by moving backtrace() calls outside of
critical sections that have the mutex acquired. The bigger change was to
reentrancy tracking for ast_cond_{timed,}wait, which wrongly assumed
that waiting on the mutex was equivalent to a single unlock (it actually
suspends all recursive locks on the mutex).

(closes issue ASTERISK-22455)
Review: https://reviewboard.asterisk.org/r/2824/
........

Merged revisions 398648 from http://svn.asterisk.org/svn/asterisk/branches/1.8
........

Merged revisions 398649 from http://svn.asterisk.org/svn/asterisk/branches/11
........

Merged revisions 398651 from http://svn.asterisk.org/svn/asterisk/branches/12


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@398652 65c4cc65-6c06-0410-ace0-fbb531ad65f3
2013-09-09 20:13:40 +00:00

1468 lines
40 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_FILE_VERSION(__FILE__, "$Revision$")
#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) */
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
t->track = NULL;
#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 = strcmp(filename, "logger.c") & track;
__ast_mutex_logger("%s line %d (%s): NOTICE: mutex '%s' is already initialized.\n",
filename, lineno, func, mutex_name);
DO_THREAD_CRASH;
*/
return 0;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if ((t->tracking = tracking)) {
ast_reentrancy_init(&t->track);
}
#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;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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 non initialized mutex
* This may no effect on linux
* And always ganerate core on *BSD with
* linked libpthread
* This not error condition if the mutex created on the fly.
*/
__ast_mutex_logger("%s line %d (%s): NOTICE: mutex '%s' is uninitialized.\n",
filename, lineno, func, mutex_name);
return 0;
}
#endif
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
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 (t->tracking) {
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 (t->tracking) {
ast_reentrancy_lock(lt);
lt->file[0] = filename;
lt->lineno[0] = lineno;
lt->func[0] = func;
lt->reentrancy = 0;
lt->thread[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;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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)) {
/* Don't warn abount uninitialized mutex.
* Simple try to initialize it.
* May be not needed in linux system.
*/
res = __ast_pthread_mutex_init(t->tracking, filename, lineno, func, mutex_name, t);
if ((t->mutex) == ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
__ast_mutex_logger("%s line %d (%s): Error: mutex '%s' is uninitialized and unable to initialize.\n",
filename, lineno, func, mutex_name);
return res;
}
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
#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);
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 (t->tracking && !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[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);
if (t->tracking) {
ast_mark_lock_acquired(t);
}
} else if (t->tracking) {
#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;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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)) {
/* Don't warn abount uninitialized mutex.
* Simple try to initialize it.
* May be not needed in linux system.
*/
res = __ast_pthread_mutex_init(t->tracking, filename, lineno, func, mutex_name, t);
if ((t->mutex) == ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
__ast_mutex_logger("%s line %d (%s): Error: mutex '%s' is uninitialized and unable to initialize.\n",
filename, lineno, func, mutex_name);
return res;
}
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
#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 (t->tracking && !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[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);
if (t->tracking) {
ast_mark_lock_acquired(t);
}
} else if (t->tracking) {
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;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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);
res = __ast_pthread_mutex_init(t->tracking, filename, lineno, func, mutex_name, t);
if ((t->mutex) == ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
__ast_mutex_logger("%s line %d (%s): Error: mutex '%s' is uninitialized and unable to initialize.\n",
filename, lineno, func, mutex_name);
}
return res;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
ast_reentrancy_lock(lt);
if (lt->reentrancy && (lt->thread[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[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);
}
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;
struct ast_lock_track lt_orig;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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);
res = __ast_pthread_mutex_init(t->tracking, filename, lineno, func, mutex_name, t);
if ((t->mutex) == ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
__ast_mutex_logger("%s line %d (%s): Error: mutex '%s' is uninitialized and unable to initialize.\n",
filename, lineno, func, mutex_name);
}
return res;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
ast_reentrancy_lock(lt);
if (lt->reentrancy && (lt->thread[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;
} else if (lt->reentrancy <= 0) {
__ast_mutex_logger("%s line %d (%s): attempted to wait on 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 (t->tracking) {
pthread_mutex_t reentr_mutex_orig;
ast_reentrancy_lock(lt);
/* Restore lock tracking to what it was prior to the wait */
reentr_mutex_orig = lt->reentr_mutex;
*lt = lt_orig;
/* un-trash the mutex we just copied over */
lt->reentr_mutex = reentr_mutex_orig;
ast_reentrancy_unlock(lt);
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;
struct ast_lock_track lt_orig;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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);
res = __ast_pthread_mutex_init(t->tracking, filename, lineno, func, mutex_name, t);
if ((t->mutex) == ((pthread_mutex_t) PTHREAD_MUTEX_INITIALIZER)) {
__ast_mutex_logger("%s line %d (%s): Error: mutex '%s' is uninitialized and unable to initialize.\n",
filename, lineno, func, mutex_name);
}
return res;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
ast_reentrancy_lock(lt);
if (lt->reentrancy && (lt->thread[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;
} else if (lt->reentrancy <= 0) {
__ast_mutex_logger("%s line %d (%s): attempted to wait on 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 (t->tracking) {
pthread_mutex_t reentr_mutex_orig;
ast_reentrancy_lock(lt);
/* Restore lock tracking to what it was prior to the wait */
reentr_mutex_orig = lt->reentr_mutex;
*lt = lt_orig;
/* un-trash the mutex we just copied over */
lt->reentr_mutex = reentr_mutex_orig;
ast_reentrancy_unlock(lt);
ast_suspend_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)
int canlog = strcmp(filename, "logger.c") & t->tracking;
if (t->lock != ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
__ast_mutex_logger("%s line %d (%s): Warning: rwlock '%s' is already initialized.\n",
filename, lineno, func, rwlock_name);
return 0;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if ((t->tracking = tracking)) {
ast_reentrancy_init(&t->track);
}
#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 = strcmp(filename, "logger.c") & t->tracking;
#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);
return 0;
}
#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 (t->tracking && lt) {
ast_reentrancy_lock(lt);
lt->file[0] = filename;
lt->lineno[0] = lineno;
lt->func[0] = func;
lt->reentrancy = 0;
lt->thread[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;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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);
res = __ast_rwlock_init(t->tracking, filename, line, func, name, t);
if ((t->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
__ast_mutex_logger("%s line %d (%s): Error: rwlock '%s' is uninitialized and unable to initialize.\n",
filename, line, func, name);
}
return res;
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
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[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[i] = lt->thread[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[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;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
/* Don't warn abount uninitialized lock.
* Simple try to initialize it.
* May be not needed in linux system.
*/
res = __ast_rwlock_init(t->tracking, filename, line, func, name, t);
if ((t->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
__ast_mutex_logger("%s line %d (%s): Error: rwlock '%s' is uninitialized and unable to initialize.\n",
filename, line, func, name);
return res;
}
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
#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 (t->tracking) {
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 && t->tracking) {
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[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
if (t->tracking) {
ast_mark_lock_acquired(t);
}
} else if (t->tracking) {
#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;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
/* Don't warn abount uninitialized lock.
* Simple try to initialize it.
* May be not needed in linux system.
*/
res = __ast_rwlock_init(t->tracking, filename, line, func, name, t);
if ((t->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
__ast_mutex_logger("%s line %d (%s): Error: rwlock '%s' is uninitialized and unable to initialize.\n",
filename, line, func, name);
return res;
}
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
#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 (t->tracking) {
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 && t->tracking) {
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[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
if (t->tracking) {
ast_mark_lock_acquired(t);
}
} else if (t->tracking) {
#ifdef HAVE_BKTR
if (lt->reentrancy) {
ast_reentrancy_lock(lt);
bt = &lt->backtrace[lt->reentrancy-1];
ast_reentrancy_unlock(lt);
} else {
bt = NULL;
}
if (t->tracking) {
ast_remove_lock_info(t, bt);
}
#else
if (t->tracking) {
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;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
/* Don't warn abount uninitialized lock.
* Simple try to initialize it.
* May be not needed in linux system.
*/
res = __ast_rwlock_init(t->tracking, filename, line, func, name, t);
if ((t->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
__ast_mutex_logger("%s line %d (%s): Error: rwlock '%s' is uninitialized and unable to initialize.\n",
filename, line, func, name);
return res;
}
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
#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 && t->tracking) {
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[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
if (t->tracking) {
ast_mark_lock_acquired(t);
}
} else if (t->tracking) {
#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;
int canlog = strcmp(filename, "logger.c") & t->tracking;
#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->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
/* Don't warn abount uninitialized lock.
* Simple try to initialize it.
* May be not needed in linux system.
*/
res = __ast_rwlock_init(t->tracking, filename, line, func, name, t);
if ((t->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
__ast_mutex_logger("%s line %d (%s): Error: rwlock '%s' is uninitialized and unable to initialize.\n",
filename, line, func, name);
return res;
}
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
#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 && t->tracking) {
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[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
if (t->tracking) {
ast_mark_lock_acquired(t);
}
} else if (t->tracking) {
#ifdef HAVE_BKTR
if (lt->reentrancy) {
ast_reentrancy_lock(lt);
bt = &lt->backtrace[lt->reentrancy-1];
ast_reentrancy_unlock(lt);
} else {
bt = NULL;
}
if (t->tracking) {
ast_remove_lock_info(t, bt);
}
#else
if (t->tracking) {
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;
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
int canlog = strcmp(filename, "logger.c") & t->tracking;
if ((t->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
/* Don't warn abount uninitialized lock.
* Simple try to initialize it.
* May be not needed in linux system.
*/
res = __ast_rwlock_init(t->tracking, filename, line, func, name, t);
if ((t->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
__ast_mutex_logger("%s line %d (%s): Error: rwlock '%s' is uninitialized and unable to initialize.\n",
filename, line, func, name);
return res;
}
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
#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 && t->tracking) {
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[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
if (t->tracking) {
ast_mark_lock_acquired(t);
}
} else if (t->tracking) {
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;
#ifdef HAVE_BKTR
struct ast_bt *bt = NULL;
#endif
#if defined(AST_MUTEX_INIT_W_CONSTRUCTORS) && defined(CAN_COMPARE_MUTEX_TO_INIT_VALUE)
int canlog = strcmp(filename, "logger.c") & t->tracking;
if ((t->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
/* Don't warn abount uninitialized lock.
* Simple try to initialize it.
* May be not needed in linux system.
*/
res = __ast_rwlock_init(t->tracking, filename, line, func, name, t);
if ((t->lock) == ((pthread_rwlock_t) __AST_RWLOCK_INIT_VALUE)) {
__ast_mutex_logger("%s line %d (%s): Error: rwlock '%s' is uninitialized and unable to initialize.\n",
filename, line, func, name);
return res;
}
}
#endif /* AST_MUTEX_INIT_W_CONSTRUCTORS */
if (t->tracking && !t->track) {
ast_reentrancy_init(&t->track);
}
lt = t->track;
if (t->tracking) {
#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 && t->tracking) {
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[lt->reentrancy] = pthread_self();
lt->reentrancy++;
}
ast_reentrancy_unlock(lt);
ast_mark_lock_acquired(t);
} else if (t->tracking) {
ast_mark_lock_failed(t);
}
#endif /* DEBUG_THREADS */
return res;
}