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|
/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 2007-2013, Digium, Inc.
*
* Dwayne M. Hubbard <dhubbard@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 Maintain a container of uniquely-named taskprocessor threads that can be shared across modules.
*
* \author Dwayne Hubbard <dhubbard@digium.com>
*/
/*** MODULEINFO
<support_level>core</support_level>
***/
#include "asterisk.h"
ASTERISK_REGISTER_FILE()
#include "asterisk/_private.h"
#include "asterisk/module.h"
#include "asterisk/time.h"
#include "asterisk/astobj2.h"
#include "asterisk/cli.h"
#include "asterisk/taskprocessor.h"
#include "asterisk/sem.h"
/*!
* \brief tps_task structure is queued to a taskprocessor
*
* tps_tasks are processed in FIFO order and freed by the taskprocessing
* thread after the task handler returns. The callback function that is assigned
* to the execute() function pointer is responsible for releasing datap resources if necessary.
*/
struct tps_task {
/*! \brief The execute() task callback function pointer */
union {
int (*execute)(void *datap);
int (*execute_local)(struct ast_taskprocessor_local *local);
} callback;
/*! \brief The data pointer for the task execute() function */
void *datap;
/*! \brief AST_LIST_ENTRY overhead */
AST_LIST_ENTRY(tps_task) list;
unsigned int wants_local:1;
};
/*! \brief tps_taskprocessor_stats maintain statistics for a taskprocessor. */
struct tps_taskprocessor_stats {
/*! \brief This is the maximum number of tasks queued at any one time */
unsigned long max_qsize;
/*! \brief This is the current number of tasks processed */
unsigned long _tasks_processed_count;
};
/*! \brief A ast_taskprocessor structure is a singleton by name */
struct ast_taskprocessor {
/*! \brief Friendly name of the taskprocessor */
const char *name;
/*! \brief Taskprocessor statistics */
struct tps_taskprocessor_stats *stats;
void *local_data;
/*! \brief Taskprocessor current queue size */
long tps_queue_size;
/*! \brief Taskprocessor queue */
AST_LIST_HEAD_NOLOCK(tps_queue, tps_task) tps_queue;
struct ast_taskprocessor_listener *listener;
/*! Current thread executing the tasks */
pthread_t thread;
/*! Indicates if the taskprocessor is currently executing a task */
unsigned int executing:1;
};
/*!
* \brief A listener for taskprocessors
*
* \since 12.0.0
*
* When a taskprocessor's state changes, the listener
* is notified of the change. This allows for tasks
* to be addressed in whatever way is appropriate for
* the module using the taskprocessor.
*/
struct ast_taskprocessor_listener {
/*! The callbacks the taskprocessor calls into to notify of state changes */
const struct ast_taskprocessor_listener_callbacks *callbacks;
/*! The taskprocessor that the listener is listening to */
struct ast_taskprocessor *tps;
/*! Data private to the listener */
void *user_data;
};
#define TPS_MAX_BUCKETS 7
/*! \brief tps_singletons is the astobj2 container for taskprocessor singletons */
static struct ao2_container *tps_singletons;
/*! \brief CLI <example>taskprocessor ping <blah></example> operation requires a ping condition */
static ast_cond_t cli_ping_cond;
/*! \brief CLI <example>taskprocessor ping <blah></example> operation requires a ping condition lock */
AST_MUTEX_DEFINE_STATIC(cli_ping_cond_lock);
/*! \brief The astobj2 hash callback for taskprocessors */
static int tps_hash_cb(const void *obj, const int flags);
/*! \brief The astobj2 compare callback for taskprocessors */
static int tps_cmp_cb(void *obj, void *arg, int flags);
/*! \brief Destroy the taskprocessor when its refcount reaches zero */
static void tps_taskprocessor_destroy(void *tps);
/*! \brief CLI <example>taskprocessor ping <blah></example> handler function */
static int tps_ping_handler(void *datap);
/*! \brief Remove the front task off the taskprocessor queue */
static struct tps_task *tps_taskprocessor_pop(struct ast_taskprocessor *tps);
/*! \brief Return the size of the taskprocessor queue */
static int tps_taskprocessor_depth(struct ast_taskprocessor *tps);
static char *cli_tps_ping(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a);
static char *cli_tps_report(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a);
static struct ast_cli_entry taskprocessor_clis[] = {
AST_CLI_DEFINE(cli_tps_ping, "Ping a named task processor"),
AST_CLI_DEFINE(cli_tps_report, "List instantiated task processors and statistics"),
};
struct default_taskprocessor_listener_pvt {
pthread_t poll_thread;
int dead;
struct ast_sem sem;
};
static void default_listener_pvt_destroy(struct default_taskprocessor_listener_pvt *pvt)
{
ast_assert(pvt->dead);
ast_sem_destroy(&pvt->sem);
ast_free(pvt);
}
static void default_listener_pvt_dtor(struct ast_taskprocessor_listener *listener)
{
struct default_taskprocessor_listener_pvt *pvt = listener->user_data;
default_listener_pvt_destroy(pvt);
listener->user_data = NULL;
}
/*!
* \brief Function that processes tasks in the taskprocessor
* \internal
*/
static void *default_tps_processing_function(void *data)
{
struct ast_taskprocessor_listener *listener = data;
struct ast_taskprocessor *tps = listener->tps;
struct default_taskprocessor_listener_pvt *pvt = listener->user_data;
int sem_value;
int res;
while (!pvt->dead) {
res = ast_sem_wait(&pvt->sem);
if (res != 0 && errno != EINTR) {
ast_log(LOG_ERROR, "ast_sem_wait(): %s\n",
strerror(errno));
/* Just give up */
break;
}
ast_taskprocessor_execute(tps);
}
/* No posting to a dead taskprocessor! */
res = ast_sem_getvalue(&pvt->sem, &sem_value);
ast_assert(res == 0 && sem_value == 0);
/* Free the shutdown reference (see default_listener_shutdown) */
ao2_t_ref(listener->tps, -1, "tps-shutdown");
return NULL;
}
static int default_listener_start(struct ast_taskprocessor_listener *listener)
{
struct default_taskprocessor_listener_pvt *pvt = listener->user_data;
if (ast_pthread_create(&pvt->poll_thread, NULL, default_tps_processing_function, listener)) {
return -1;
}
return 0;
}
static void default_task_pushed(struct ast_taskprocessor_listener *listener, int was_empty)
{
struct default_taskprocessor_listener_pvt *pvt = listener->user_data;
if (ast_sem_post(&pvt->sem) != 0) {
ast_log(LOG_ERROR, "Failed to notify of enqueued task: %s\n",
strerror(errno));
}
}
static int default_listener_die(void *data)
{
struct default_taskprocessor_listener_pvt *pvt = data;
pvt->dead = 1;
return 0;
}
static void default_listener_shutdown(struct ast_taskprocessor_listener *listener)
{
struct default_taskprocessor_listener_pvt *pvt = listener->user_data;
int res;
/* Hold a reference during shutdown */
ao2_t_ref(listener->tps, +1, "tps-shutdown");
ast_taskprocessor_push(listener->tps, default_listener_die, pvt);
ast_assert(pvt->poll_thread != AST_PTHREADT_NULL);
if (pthread_equal(pthread_self(), pvt->poll_thread)) {
res = pthread_detach(pvt->poll_thread);
if (res != 0) {
ast_log(LOG_ERROR, "pthread_detach(): %s\n", strerror(errno));
}
} else {
res = pthread_join(pvt->poll_thread, NULL);
if (res != 0) {
ast_log(LOG_ERROR, "pthread_join(): %s\n", strerror(errno));
}
}
pvt->poll_thread = AST_PTHREADT_NULL;
}
static const struct ast_taskprocessor_listener_callbacks default_listener_callbacks = {
.start = default_listener_start,
.task_pushed = default_task_pushed,
.shutdown = default_listener_shutdown,
.dtor = default_listener_pvt_dtor,
};
/*!
* \internal
* \brief Clean up resources on Asterisk shutdown
*/
static void tps_shutdown(void)
{
ast_cli_unregister_multiple(taskprocessor_clis, ARRAY_LEN(taskprocessor_clis));
ao2_t_ref(tps_singletons, -1, "Unref tps_singletons in shutdown");
tps_singletons = NULL;
}
/* initialize the taskprocessor container and register CLI operations */
int ast_tps_init(void)
{
if (!(tps_singletons = ao2_container_alloc(TPS_MAX_BUCKETS, tps_hash_cb, tps_cmp_cb))) {
ast_log(LOG_ERROR, "taskprocessor container failed to initialize!\n");
return -1;
}
ast_cond_init(&cli_ping_cond, NULL);
ast_cli_register_multiple(taskprocessor_clis, ARRAY_LEN(taskprocessor_clis));
ast_register_cleanup(tps_shutdown);
return 0;
}
/* allocate resources for the task */
static struct tps_task *tps_task_alloc(int (*task_exe)(void *datap), void *datap)
{
struct tps_task *t;
if (!task_exe) {
ast_log(LOG_ERROR, "task_exe is NULL!\n");
return NULL;
}
t = ast_calloc(1, sizeof(*t));
if (!t) {
ast_log(LOG_ERROR, "failed to allocate task!\n");
return NULL;
}
t->callback.execute = task_exe;
t->datap = datap;
return t;
}
static struct tps_task *tps_task_alloc_local(int (*task_exe)(struct ast_taskprocessor_local *local), void *datap)
{
struct tps_task *t;
if (!task_exe) {
ast_log(LOG_ERROR, "task_exe is NULL!\n");
return NULL;
}
t = ast_calloc(1, sizeof(*t));
if (!t) {
ast_log(LOG_ERROR, "failed to allocate task!\n");
return NULL;
}
t->callback.execute_local = task_exe;
t->datap = datap;
t->wants_local = 1;
return t;
}
/* release task resources */
static void *tps_task_free(struct tps_task *task)
{
ast_free(task);
return NULL;
}
/* taskprocessor tab completion */
static char *tps_taskprocessor_tab_complete(struct ast_taskprocessor *p, struct ast_cli_args *a)
{
int tklen;
int wordnum = 0;
char *name = NULL;
struct ao2_iterator i;
if (a->pos != 3)
return NULL;
tklen = strlen(a->word);
i = ao2_iterator_init(tps_singletons, 0);
while ((p = ao2_iterator_next(&i))) {
if (!strncasecmp(a->word, p->name, tklen) && ++wordnum > a->n) {
name = ast_strdup(p->name);
ao2_ref(p, -1);
break;
}
ao2_ref(p, -1);
}
ao2_iterator_destroy(&i);
return name;
}
/* ping task handling function */
static int tps_ping_handler(void *datap)
{
ast_mutex_lock(&cli_ping_cond_lock);
ast_cond_signal(&cli_ping_cond);
ast_mutex_unlock(&cli_ping_cond_lock);
return 0;
}
/* ping the specified taskprocessor and display the ping time on the CLI */
static char *cli_tps_ping(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
struct timeval begin, end, delta;
const char *name;
struct timeval when;
struct timespec ts;
struct ast_taskprocessor *tps = NULL;
switch (cmd) {
case CLI_INIT:
e->command = "core ping taskprocessor";
e->usage =
"Usage: core ping taskprocessor <taskprocessor>\n"
" Displays the time required for a task to be processed\n";
return NULL;
case CLI_GENERATE:
return tps_taskprocessor_tab_complete(tps, a);
}
if (a->argc != 4)
return CLI_SHOWUSAGE;
name = a->argv[3];
if (!(tps = ast_taskprocessor_get(name, TPS_REF_IF_EXISTS))) {
ast_cli(a->fd, "\nping failed: %s not found\n\n", name);
return CLI_SUCCESS;
}
ast_cli(a->fd, "\npinging %s ...", name);
when = ast_tvadd((begin = ast_tvnow()), ast_samp2tv(1000, 1000));
ts.tv_sec = when.tv_sec;
ts.tv_nsec = when.tv_usec * 1000;
ast_mutex_lock(&cli_ping_cond_lock);
if (ast_taskprocessor_push(tps, tps_ping_handler, 0) < 0) {
ast_cli(a->fd, "\nping failed: could not push task to %s\n\n", name);
ao2_ref(tps, -1);
return CLI_FAILURE;
}
ast_cond_timedwait(&cli_ping_cond, &cli_ping_cond_lock, &ts);
ast_mutex_unlock(&cli_ping_cond_lock);
end = ast_tvnow();
delta = ast_tvsub(end, begin);
ast_cli(a->fd, "\n\t%24s ping time: %.1ld.%.6ld sec\n\n", name, (long)delta.tv_sec, (long int)delta.tv_usec);
ao2_ref(tps, -1);
return CLI_SUCCESS;
}
static char *cli_tps_report(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
char name[256];
int tcount;
unsigned long qsize;
unsigned long maxqsize;
unsigned long processed;
struct ast_taskprocessor *p;
struct ao2_iterator i;
switch (cmd) {
case CLI_INIT:
e->command = "core show taskprocessors";
e->usage =
"Usage: core show taskprocessors\n"
" Shows a list of instantiated task processors and their statistics\n";
return NULL;
case CLI_GENERATE:
return NULL;
}
if (a->argc != e->args)
return CLI_SHOWUSAGE;
ast_cli(a->fd, "\n\t+----- Processor -----+--- Processed ---+- In Queue -+- Max Depth -+");
i = ao2_iterator_init(tps_singletons, 0);
while ((p = ao2_iterator_next(&i))) {
ast_copy_string(name, p->name, sizeof(name));
qsize = p->tps_queue_size;
maxqsize = p->stats->max_qsize;
processed = p->stats->_tasks_processed_count;
ast_cli(a->fd, "\n%24s %17lu %12lu %12lu", name, processed, qsize, maxqsize);
ao2_ref(p, -1);
}
ao2_iterator_destroy(&i);
tcount = ao2_container_count(tps_singletons);
ast_cli(a->fd, "\n\t+---------------------+-----------------+------------+-------------+\n\t%d taskprocessors\n\n", tcount);
return CLI_SUCCESS;
}
/* hash callback for astobj2 */
static int tps_hash_cb(const void *obj, const int flags)
{
const struct ast_taskprocessor *tps = obj;
const char *name = flags & OBJ_KEY ? obj : tps->name;
return ast_str_case_hash(name);
}
/* compare callback for astobj2 */
static int tps_cmp_cb(void *obj, void *arg, int flags)
{
struct ast_taskprocessor *lhs = obj, *rhs = arg;
const char *rhsname = flags & OBJ_KEY ? arg : rhs->name;
return !strcasecmp(lhs->name, rhsname) ? CMP_MATCH | CMP_STOP : 0;
}
/* destroy the taskprocessor */
static void tps_taskprocessor_destroy(void *tps)
{
struct ast_taskprocessor *t = tps;
struct tps_task *task;
if (!tps) {
ast_log(LOG_ERROR, "missing taskprocessor\n");
return;
}
ast_debug(1, "destroying taskprocessor '%s'\n", t->name);
/* free it */
ast_free(t->stats);
t->stats = NULL;
ast_free((char *) t->name);
if (t->listener) {
ao2_ref(t->listener, -1);
t->listener = NULL;
}
while ((task = AST_LIST_REMOVE_HEAD(&t->tps_queue, list))) {
tps_task_free(task);
}
}
/* pop the front task and return it */
static struct tps_task *tps_taskprocessor_pop(struct ast_taskprocessor *tps)
{
struct tps_task *task;
if ((task = AST_LIST_REMOVE_HEAD(&tps->tps_queue, list))) {
tps->tps_queue_size--;
}
return task;
}
static int tps_taskprocessor_depth(struct ast_taskprocessor *tps)
{
return (tps) ? tps->tps_queue_size : -1;
}
/* taskprocessor name accessor */
const char *ast_taskprocessor_name(struct ast_taskprocessor *tps)
{
if (!tps) {
ast_log(LOG_ERROR, "no taskprocessor specified!\n");
return NULL;
}
return tps->name;
}
static void listener_shutdown(struct ast_taskprocessor_listener *listener)
{
listener->callbacks->shutdown(listener);
ao2_ref(listener->tps, -1);
}
static void taskprocessor_listener_dtor(void *obj)
{
struct ast_taskprocessor_listener *listener = obj;
if (listener->callbacks->dtor) {
listener->callbacks->dtor(listener);
}
}
struct ast_taskprocessor_listener *ast_taskprocessor_listener_alloc(const struct ast_taskprocessor_listener_callbacks *callbacks, void *user_data)
{
struct ast_taskprocessor_listener *listener;
listener = ao2_alloc(sizeof(*listener), taskprocessor_listener_dtor);
if (!listener) {
return NULL;
}
listener->callbacks = callbacks;
listener->user_data = user_data;
return listener;
}
struct ast_taskprocessor *ast_taskprocessor_listener_get_tps(const struct ast_taskprocessor_listener *listener)
{
ao2_ref(listener->tps, +1);
return listener->tps;
}
void *ast_taskprocessor_listener_get_user_data(const struct ast_taskprocessor_listener *listener)
{
return listener->user_data;
}
static void *default_listener_pvt_alloc(void)
{
struct default_taskprocessor_listener_pvt *pvt;
pvt = ast_calloc(1, sizeof(*pvt));
if (!pvt) {
return NULL;
}
pvt->poll_thread = AST_PTHREADT_NULL;
if (ast_sem_init(&pvt->sem, 0, 0) != 0) {
ast_log(LOG_ERROR, "ast_sem_init(): %s\n", strerror(errno));
ast_free(pvt);
return NULL;
}
return pvt;
}
static struct ast_taskprocessor *__allocate_taskprocessor(const char *name, struct ast_taskprocessor_listener *listener)
{
RAII_VAR(struct ast_taskprocessor *, p,
ao2_alloc(sizeof(*p), tps_taskprocessor_destroy), ao2_cleanup);
if (!p) {
ast_log(LOG_WARNING, "failed to create taskprocessor '%s'\n", name);
return NULL;
}
if (!(p->stats = ast_calloc(1, sizeof(*p->stats)))) {
ast_log(LOG_WARNING, "failed to create taskprocessor stats for '%s'\n", name);
return NULL;
}
if (!(p->name = ast_strdup(name))) {
return NULL;
}
ao2_ref(listener, +1);
p->listener = listener;
p->thread = AST_PTHREADT_NULL;
ao2_ref(p, +1);
listener->tps = p;
if (!(ao2_link(tps_singletons, p))) {
ast_log(LOG_ERROR, "Failed to add taskprocessor '%s' to container\n", p->name);
return NULL;
}
if (p->listener->callbacks->start(p->listener)) {
ast_log(LOG_ERROR, "Unable to start taskprocessor listener for taskprocessor %s\n", p->name);
ast_taskprocessor_unreference(p);
return NULL;
}
/* RAII_VAR will decrement the refcount at the end of the function.
* Since we want to pass back a reference to p, we bump the refcount
*/
ao2_ref(p, +1);
return p;
}
/* Provide a reference to a taskprocessor. Create the taskprocessor if necessary, but don't
* create the taskprocessor if we were told via ast_tps_options to return a reference only
* if it already exists */
struct ast_taskprocessor *ast_taskprocessor_get(const char *name, enum ast_tps_options create)
{
struct ast_taskprocessor *p;
struct ast_taskprocessor_listener *listener;
struct default_taskprocessor_listener_pvt *pvt;
if (ast_strlen_zero(name)) {
ast_log(LOG_ERROR, "requesting a nameless taskprocessor!!!\n");
return NULL;
}
p = ao2_find(tps_singletons, name, OBJ_KEY);
if (p) {
return p;
}
if (create & TPS_REF_IF_EXISTS) {
/* calling function does not want a new taskprocessor to be created if it doesn't already exist */
return NULL;
}
/* Create a new taskprocessor. Start by creating a default listener */
pvt = default_listener_pvt_alloc();
if (!pvt) {
return NULL;
}
listener = ast_taskprocessor_listener_alloc(&default_listener_callbacks, pvt);
if (!listener) {
default_listener_pvt_destroy(pvt);
return NULL;
}
p = __allocate_taskprocessor(name, listener);
if (!p) {
ao2_ref(listener, -1);
return NULL;
}
/* Unref listener here since the taskprocessor has gained a reference to the listener */
ao2_ref(listener, -1);
return p;
}
struct ast_taskprocessor *ast_taskprocessor_create_with_listener(const char *name, struct ast_taskprocessor_listener *listener)
{
struct ast_taskprocessor *p = ao2_find(tps_singletons, name, OBJ_KEY);
if (p) {
ast_taskprocessor_unreference(p);
return NULL;
}
return __allocate_taskprocessor(name, listener);
}
void ast_taskprocessor_set_local(struct ast_taskprocessor *tps,
void *local_data)
{
SCOPED_AO2LOCK(lock, tps);
tps->local_data = local_data;
}
/* decrement the taskprocessor reference count and unlink from the container if necessary */
void *ast_taskprocessor_unreference(struct ast_taskprocessor *tps)
{
if (!tps) {
return NULL;
}
/* To prevent another thread from finding and getting a reference to this
* taskprocessor we hold the singletons lock. If we didn't do this then
* they may acquire it and find that the listener has been shut down.
*/
ao2_lock(tps_singletons);
if (ao2_ref(tps, -1) > 3) {
ao2_unlock(tps_singletons);
return NULL;
}
/* If we're down to 3 references, then those must be:
* 1. The reference we just got rid of
* 2. The container
* 3. The listener
*/
ao2_unlink_flags(tps_singletons, tps, OBJ_NOLOCK);
ao2_unlock(tps_singletons);
listener_shutdown(tps->listener);
return NULL;
}
/* push the task into the taskprocessor queue */
static int taskprocessor_push(struct ast_taskprocessor *tps, struct tps_task *t)
{
int previous_size;
int was_empty;
if (!tps) {
ast_log(LOG_ERROR, "tps is NULL!\n");
return -1;
}
if (!t) {
ast_log(LOG_ERROR, "t is NULL!\n");
return -1;
}
ao2_lock(tps);
AST_LIST_INSERT_TAIL(&tps->tps_queue, t, list);
previous_size = tps->tps_queue_size++;
/* The currently executing task counts as still in queue */
was_empty = tps->executing ? 0 : previous_size == 0;
ao2_unlock(tps);
tps->listener->callbacks->task_pushed(tps->listener, was_empty);
return 0;
}
int ast_taskprocessor_push(struct ast_taskprocessor *tps, int (*task_exe)(void *datap), void *datap)
{
return taskprocessor_push(tps, tps_task_alloc(task_exe, datap));
}
int ast_taskprocessor_push_local(struct ast_taskprocessor *tps, int (*task_exe)(struct ast_taskprocessor_local *datap), void *datap)
{
return taskprocessor_push(tps, tps_task_alloc_local(task_exe, datap));
}
int ast_taskprocessor_execute(struct ast_taskprocessor *tps)
{
struct ast_taskprocessor_local local;
struct tps_task *t;
int size;
ao2_lock(tps);
t = tps_taskprocessor_pop(tps);
if (!t) {
ao2_unlock(tps);
return 0;
}
tps->thread = pthread_self();
tps->executing = 1;
if (t->wants_local) {
local.local_data = tps->local_data;
local.data = t->datap;
}
ao2_unlock(tps);
if (t->wants_local) {
t->callback.execute_local(&local);
} else {
t->callback.execute(t->datap);
}
tps_task_free(t);
ao2_lock(tps);
tps->thread = AST_PTHREADT_NULL;
/* We need to check size in the same critical section where we reset the
* executing bit. Avoids a race condition where a task is pushed right
* after we pop an empty stack.
*/
tps->executing = 0;
size = tps_taskprocessor_depth(tps);
/* If we executed a task, bump the stats */
if (tps->stats) {
tps->stats->_tasks_processed_count++;
if (size > tps->stats->max_qsize) {
tps->stats->max_qsize = size;
}
}
ao2_unlock(tps);
/* If we executed a task, check for the transition to empty */
if (size == 0 && tps->listener->callbacks->emptied) {
tps->listener->callbacks->emptied(tps->listener);
}
return size > 0;
}
int ast_taskprocessor_is_task(struct ast_taskprocessor *tps)
{
int is_task;
ao2_lock(tps);
is_task = pthread_equal(tps->thread, pthread_self());
ao2_unlock(tps);
return is_task;
}
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