X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=glib%2Fgthreadpool.c;h=dad424dca6e123f3f8f7b916dc1d1d47707cc6b6;hb=0a4ee12c7a9dfc82443133dfb2b18fb411d79f48;hp=3ece1b445e73b9bcdceb874de261ed47f386ef3f;hpb=d81506a154ba387e339dfb5ff6acddac1e4866c5;p=platform%2Fupstream%2Fglib.git diff --git a/glib/gthreadpool.c b/glib/gthreadpool.c index 3ece1b4..dad424d 100644 --- a/glib/gthreadpool.c +++ b/glib/gthreadpool.c @@ -1,7 +1,7 @@ /* GLIB - Library of useful routines for C programming * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald * - * GAsyncQueue: thread pool implementation. + * GThreadPool: thread pool implementation. * Copyright (C) 2000 Sebastian Wilhelmi; University of Karlsruhe * * This library is free software; you can redistribute it and/or @@ -15,9 +15,7 @@ * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public - * License along with this library; if not, write to the - * Free Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 02111-1307, USA. + * License along with this library; if not, see . */ /* @@ -26,17 +24,19 @@ #include "config.h" -#include "glib.h" -#include "galias.h" +#include "gthreadpool.h" + +#include "gasyncqueue.h" +#include "gasyncqueueprivate.h" +#include "gmain.h" +#include "gtestutils.h" +#include "gtimer.h" /** - * SECTION: thread_pools + * SECTION:thread_pools * @title: Thread Pools * @short_description: pools of threads to execute work concurrently - * @see_also: - * #GThread GLib thread - * system. - * + * @see_also: #GThread * * Sometimes you wish to asynchronously fork out the execution of work * and continue working in your own thread. If that will happen often, @@ -49,11 +49,11 @@ * advantage is, that the threads can be shared between the different * subsystems of your program, when they are using GLib. * - * To create a new thread pool, you use g_thread_pool_new(). It is - * destroyed by g_thread_pool_free(). + * To create a new thread pool, you use g_thread_pool_new(). + * It is destroyed by g_thread_pool_free(). * - * If you want to execute a certain task within a thread pool, you call - * g_thread_pool_push(). + * If you want to execute a certain task within a thread pool, + * you call g_thread_pool_push(). * * To get the current number of running threads you call * g_thread_pool_get_num_threads(). To get the number of still @@ -67,9 +67,9 @@ * controlled by g_thread_pool_get_max_unused_threads() and * g_thread_pool_set_max_unused_threads(). All currently unused threads * can be stopped by calling g_thread_pool_stop_unused_threads(). - **/ + */ -#define DEBUG_MSG(x) +#define DEBUG_MSG(x) /* #define DEBUG_MSG(args) g_printerr args ; g_printerr ("\n"); */ typedef struct _GRealThreadPool GRealThreadPool; @@ -81,14 +81,14 @@ typedef struct _GRealThreadPool GRealThreadPool; * @exclusive: are all threads exclusive to this pool * * The #GThreadPool struct represents a thread pool. It has three - * public read-only members, but the underlying struct is bigger, so - * you must not copy this struct. - **/ + * public read-only members, but the underlying struct is bigger, + * so you must not copy this struct. + */ struct _GRealThreadPool { GThreadPool pool; - GAsyncQueue* queue; - GCond* cond; + GAsyncQueue *queue; + GCond cond; gint max_threads; gint num_threads; gboolean running; @@ -100,36 +100,37 @@ struct _GRealThreadPool /* The following is just an address to mark the wakeup order for a * thread, it could be any address (as long, as it isn't a valid - * GThreadPool address) */ + * GThreadPool address) + */ static const gpointer wakeup_thread_marker = (gpointer) &g_thread_pool_new; static gint wakeup_thread_serial = 0; /* Here all unused threads are waiting */ static GAsyncQueue *unused_thread_queue = NULL; static gint unused_threads = 0; -static gint max_unused_threads = 0; +static gint max_unused_threads = 2; static gint kill_unused_threads = 0; -static guint max_idle_time = 0; +static guint max_idle_time = 15 * 1000; static void g_thread_pool_queue_push_unlocked (GRealThreadPool *pool, - gpointer data); + gpointer data); static void g_thread_pool_free_internal (GRealThreadPool *pool); static gpointer g_thread_pool_thread_proxy (gpointer data); -static void g_thread_pool_start_thread (GRealThreadPool *pool, - GError **error); +static gboolean g_thread_pool_start_thread (GRealThreadPool *pool, + GError **error); static void g_thread_pool_wakeup_and_stop_all (GRealThreadPool *pool); static GRealThreadPool* g_thread_pool_wait_for_new_pool (void); static gpointer g_thread_pool_wait_for_new_task (GRealThreadPool *pool); static void g_thread_pool_queue_push_unlocked (GRealThreadPool *pool, - gpointer data) + gpointer data) { - if (pool->sort_func) - g_async_queue_push_sorted_unlocked (pool->queue, - data, - pool->sort_func, - pool->sort_user_data); + if (pool->sort_func) + g_async_queue_push_sorted_unlocked (pool->queue, + data, + pool->sort_func, + pool->sort_user_data); else g_async_queue_push_unlocked (pool->queue, data); } @@ -153,72 +154,68 @@ g_thread_pool_wait_for_new_pool (void) do { if (g_atomic_int_get (&unused_threads) >= local_max_unused_threads) - { - /* If this is a superfluous thread, stop it. */ - pool = NULL; - } + { + /* If this is a superfluous thread, stop it. */ + pool = NULL; + } else if (local_max_idle_time > 0) - { - /* If a maximal idle time is given, wait for the given time. */ - GTimeVal end_time; - - g_get_current_time (&end_time); - g_time_val_add (&end_time, local_max_idle_time * 1000); - - DEBUG_MSG (("thread %p waiting in global pool for %f seconds.", - g_thread_self (), local_max_idle_time / 1000.0)); - - pool = g_async_queue_timed_pop (unused_thread_queue, &end_time); - } + { + /* If a maximal idle time is given, wait for the given time. */ + DEBUG_MSG (("thread %p waiting in global pool for %f seconds.", + g_thread_self (), local_max_idle_time / 1000.0)); + + pool = g_async_queue_timeout_pop (unused_thread_queue, + local_max_idle_time * 1000); + } else - { - /* If no maximal idle time is given, wait indefinitely. */ - DEBUG_MSG (("thread %p waiting in global pool.", - g_thread_self ())); - pool = g_async_queue_pop (unused_thread_queue); - } + { + /* If no maximal idle time is given, wait indefinitely. */ + DEBUG_MSG (("thread %p waiting in global pool.", g_thread_self ())); + pool = g_async_queue_pop (unused_thread_queue); + } if (pool == wakeup_thread_marker) - { - local_wakeup_thread_serial = g_atomic_int_get (&wakeup_thread_serial); - if (last_wakeup_thread_serial == local_wakeup_thread_serial) - { - if (!have_relayed_thread_marker) - { - /* If this wakeup marker has been received for - * the second time, relay it. - */ - DEBUG_MSG (("thread %p relaying wakeup message to " - "waiting thread with lower serial.", - g_thread_self ())); - - g_async_queue_push (unused_thread_queue, wakeup_thread_marker); - have_relayed_thread_marker = TRUE; - - /* If a wakeup marker has been relayed, this thread - * will get out of the way for 100 microseconds to - * avoid receiving this marker again. */ - g_usleep (100); - } - } - else - { - if (g_atomic_int_exchange_and_add (&kill_unused_threads, -1) > 0) - { - pool = NULL; - break; - } - - DEBUG_MSG (("thread %p updating to new limits.", - g_thread_self ())); - - local_max_unused_threads = g_atomic_int_get (&max_unused_threads); - local_max_idle_time = g_atomic_int_get (&max_idle_time); - last_wakeup_thread_serial = local_wakeup_thread_serial; - - have_relayed_thread_marker = FALSE; - } - } + { + local_wakeup_thread_serial = g_atomic_int_get (&wakeup_thread_serial); + if (last_wakeup_thread_serial == local_wakeup_thread_serial) + { + if (!have_relayed_thread_marker) + { + /* If this wakeup marker has been received for + * the second time, relay it. + */ + DEBUG_MSG (("thread %p relaying wakeup message to " + "waiting thread with lower serial.", + g_thread_self ())); + + g_async_queue_push (unused_thread_queue, wakeup_thread_marker); + have_relayed_thread_marker = TRUE; + + /* If a wakeup marker has been relayed, this thread + * will get out of the way for 100 microseconds to + * avoid receiving this marker again. + */ + g_usleep (100); + } + } + else + { + if (g_atomic_int_add (&kill_unused_threads, -1) > 0) + { + pool = NULL; + break; + } + + DEBUG_MSG (("thread %p updating to new limits.", + g_thread_self ())); + + local_max_unused_threads = g_atomic_int_get (&max_unused_threads); + local_max_idle_time = g_atomic_int_get (&max_idle_time); + last_wakeup_thread_serial = local_wakeup_thread_serial; + + have_relayed_thread_marker = FALSE; + } + } } while (pool == wakeup_thread_marker); @@ -233,67 +230,62 @@ g_thread_pool_wait_for_new_task (GRealThreadPool *pool) gpointer task = NULL; if (pool->running || (!pool->immediate && - g_async_queue_length_unlocked (pool->queue) > 0)) + g_async_queue_length_unlocked (pool->queue) > 0)) { /* This thread pool is still active. */ if (pool->num_threads > pool->max_threads && pool->max_threads != -1) - { - /* This is a superfluous thread, so it goes to the global pool. */ - DEBUG_MSG (("superfluous thread %p in pool %p.", - g_thread_self (), pool)); - } + { + /* This is a superfluous thread, so it goes to the global pool. */ + DEBUG_MSG (("superfluous thread %p in pool %p.", + g_thread_self (), pool)); + } else if (pool->pool.exclusive) - { - /* Exclusive threads stay attached to the pool. */ - task = g_async_queue_pop_unlocked (pool->queue); - - DEBUG_MSG (("thread %p in exclusive pool %p waits for task " - "(%d running, %d unprocessed).", - g_thread_self (), pool, pool->num_threads, - g_async_queue_length_unlocked (pool->queue))); - } + { + /* Exclusive threads stay attached to the pool. */ + task = g_async_queue_pop_unlocked (pool->queue); + + DEBUG_MSG (("thread %p in exclusive pool %p waits for task " + "(%d running, %d unprocessed).", + g_thread_self (), pool, pool->num_threads, + g_async_queue_length_unlocked (pool->queue))); + } else - { - /* A thread will wait for new tasks for at most 1/2 - * second before going to the global pool. - */ - GTimeVal end_time; - - g_get_current_time (&end_time); - g_time_val_add (&end_time, G_USEC_PER_SEC / 2); /* 1/2 second */ - - DEBUG_MSG (("thread %p in pool %p waits for up to a 1/2 second for task " - "(%d running, %d unprocessed).", - g_thread_self (), pool, pool->num_threads, - g_async_queue_length_unlocked (pool->queue))); - - task = g_async_queue_timed_pop_unlocked (pool->queue, &end_time); - } + { + /* A thread will wait for new tasks for at most 1/2 + * second before going to the global pool. + */ + DEBUG_MSG (("thread %p in pool %p waits for up to a 1/2 second for task " + "(%d running, %d unprocessed).", + g_thread_self (), pool, pool->num_threads, + g_async_queue_length_unlocked (pool->queue))); + + task = g_async_queue_timeout_pop_unlocked (pool->queue, + G_USEC_PER_SEC / 2); + } } else { /* This thread pool is inactive, it will no longer process tasks. */ DEBUG_MSG (("pool %p not active, thread %p will go to global pool " - "(running: %s, immediate: %s, len: %d).", - pool, g_thread_self (), - pool->running ? "true" : "false", - pool->immediate ? "true" : "false", - g_async_queue_length_unlocked (pool->queue))); + "(running: %s, immediate: %s, len: %d).", + pool, g_thread_self (), + pool->running ? "true" : "false", + pool->immediate ? "true" : "false", + g_async_queue_length_unlocked (pool->queue))); } return task; } -static gpointer +static gpointer g_thread_pool_thread_proxy (gpointer data) { GRealThreadPool *pool; pool = data; - DEBUG_MSG (("thread %p started for pool %p.", - g_thread_self (), pool)); + DEBUG_MSG (("thread %p started for pool %p.", g_thread_self (), pool)); g_async_queue_lock (pool->queue); @@ -303,101 +295,99 @@ g_thread_pool_thread_proxy (gpointer data) task = g_thread_pool_wait_for_new_task (pool); if (task) - { - if (pool->running || !pool->immediate) - { - /* A task was received and the thread pool is active, so - * execute the function. - */ - g_async_queue_unlock (pool->queue); - DEBUG_MSG (("thread %p in pool %p calling func.", - g_thread_self (), pool)); - pool->pool.func (task, pool->pool.user_data); - g_async_queue_lock (pool->queue); - } - } + { + if (pool->running || !pool->immediate) + { + /* A task was received and the thread pool is active, + * so execute the function. + */ + g_async_queue_unlock (pool->queue); + DEBUG_MSG (("thread %p in pool %p calling func.", + g_thread_self (), pool)); + pool->pool.func (task, pool->pool.user_data); + g_async_queue_lock (pool->queue); + } + } else - { - /* No task was received, so this thread goes to the global - * pool. - */ - gboolean free_pool = FALSE; - - DEBUG_MSG (("thread %p leaving pool %p for global pool.", - g_thread_self (), pool)); - pool->num_threads--; - - if (!pool->running) - { - if (!pool->waiting) - { - if (pool->num_threads == 0) - { - /* If the pool is not running and no other - * thread is waiting for this thread pool to - * finish and this is the last thread of this - * pool, free the pool. - */ - free_pool = TRUE; - } - else - { - /* If the pool is not running and no other - * thread is waiting for this thread pool to - * finish and this is not the last thread of - * this pool and there are no tasks left in the - * queue, wakeup the remaining threads. - */ - if (g_async_queue_length_unlocked (pool->queue) == - - pool->num_threads) - g_thread_pool_wakeup_and_stop_all (pool); - } - } - else if (pool->immediate || - g_async_queue_length_unlocked (pool->queue) <= 0) - { - /* If the pool is not running and another thread is - * waiting for this thread pool to finish and there - * are either no tasks left or the pool shall stop - * immediatly, inform the waiting thread of a change - * of the thread pool state. - */ - g_cond_broadcast (pool->cond); - } - } - - g_async_queue_unlock (pool->queue); - - if (free_pool) - g_thread_pool_free_internal (pool); - - if ((pool = g_thread_pool_wait_for_new_pool ()) == NULL) - break; - - g_async_queue_lock (pool->queue); - - DEBUG_MSG (("thread %p entering pool %p from global pool.", - g_thread_self (), pool)); - - /* pool->num_threads++ is not done here, but in - * g_thread_pool_start_thread to make the new started thread - * known to the pool, before itself can do it. - */ - } + { + /* No task was received, so this thread goes to the global pool. */ + gboolean free_pool = FALSE; + + DEBUG_MSG (("thread %p leaving pool %p for global pool.", + g_thread_self (), pool)); + pool->num_threads--; + + if (!pool->running) + { + if (!pool->waiting) + { + if (pool->num_threads == 0) + { + /* If the pool is not running and no other + * thread is waiting for this thread pool to + * finish and this is the last thread of this + * pool, free the pool. + */ + free_pool = TRUE; + } + else + { + /* If the pool is not running and no other + * thread is waiting for this thread pool to + * finish and this is not the last thread of + * this pool and there are no tasks left in the + * queue, wakeup the remaining threads. + */ + if (g_async_queue_length_unlocked (pool->queue) == + - pool->num_threads) + g_thread_pool_wakeup_and_stop_all (pool); + } + } + else if (pool->immediate || + g_async_queue_length_unlocked (pool->queue) <= 0) + { + /* If the pool is not running and another thread is + * waiting for this thread pool to finish and there + * are either no tasks left or the pool shall stop + * immediately, inform the waiting thread of a change + * of the thread pool state. + */ + g_cond_broadcast (&pool->cond); + } + } + + g_async_queue_unlock (pool->queue); + + if (free_pool) + g_thread_pool_free_internal (pool); + + if ((pool = g_thread_pool_wait_for_new_pool ()) == NULL) + break; + + g_async_queue_lock (pool->queue); + + DEBUG_MSG (("thread %p entering pool %p from global pool.", + g_thread_self (), pool)); + + /* pool->num_threads++ is not done here, but in + * g_thread_pool_start_thread to make the new started + * thread known to the pool before itself can do it. + */ + } } return NULL; } -static void -g_thread_pool_start_thread (GRealThreadPool *pool, - GError **error) +static gboolean +g_thread_pool_start_thread (GRealThreadPool *pool, + GError **error) { gboolean success = FALSE; - + if (pool->num_threads >= pool->max_threads && pool->max_threads != -1) /* Enough threads are already running */ - return; + return TRUE; g_async_queue_lock (unused_thread_queue); @@ -411,32 +401,34 @@ g_thread_pool_start_thread (GRealThreadPool *pool, if (!success) { - GError *local_error = NULL; + GThread *thread; + /* No thread was found, we have to start a new one */ - g_thread_create (g_thread_pool_thread_proxy, pool, FALSE, &local_error); - - if (local_error) - { - g_propagate_error (error, local_error); - return; - } + thread = g_thread_try_new ("pool", g_thread_pool_thread_proxy, pool, error); + + if (thread == NULL) + return FALSE; + + g_thread_unref (thread); } /* See comment in g_thread_pool_thread_proxy as to why this is done * here and not there */ pool->num_threads++; + + return TRUE; } /** - * g_thread_pool_new: + * g_thread_pool_new: * @func: a function to execute in the threads of the new thread pool - * @user_data: user data that is handed over to @func every time it - * is called - * @max_threads: the maximal number of threads to execute concurrently in - * the new thread pool, -1 means no limit + * @user_data: user data that is handed over to @func every time it + * is called + * @max_threads: the maximal number of threads to execute concurrently + * in the new thread pool, -1 means no limit * @exclusive: should this thread pool be exclusive? - * @error: return location for error + * @error: return location for error, or %NULL * * This function creates a new thread pool. * @@ -444,31 +436,36 @@ g_thread_pool_start_thread (GRealThreadPool *pool, * created or an unused one is reused. At most @max_threads threads * are running concurrently for this thread pool. @max_threads = -1 * allows unlimited threads to be created for this thread pool. The - * newly created or reused thread now executes the function @func with - * the two arguments. The first one is the parameter to + * newly created or reused thread now executes the function @func + * with the two arguments. The first one is the parameter to * g_thread_pool_push() and the second one is @user_data. * - * The parameter @exclusive determines, whether the thread pool owns - * all threads exclusive or whether the threads are shared - * globally. If @exclusive is %TRUE, @max_threads threads are started - * immediately and they will run exclusively for this thread pool until - * it is destroyed by g_thread_pool_free(). If @exclusive is %FALSE, - * threads are created, when needed and shared between all - * non-exclusive thread pools. This implies that @max_threads may not - * be -1 for exclusive thread pools. + * The parameter @exclusive determines whether the thread pool owns + * all threads exclusive or shares them with other thread pools. + * If @exclusive is %TRUE, @max_threads threads are started + * immediately and they will run exclusively for this thread pool + * until it is destroyed by g_thread_pool_free(). If @exclusive is + * %FALSE, threads are created when needed and shared between all + * non-exclusive thread pools. This implies that @max_threads may + * not be -1 for exclusive thread pools. Besides, exclusive thread + * pools are not affected by g_thread_pool_set_max_idle_time() + * since their threads are never considered idle and returned to the + * global pool. * * @error can be %NULL to ignore errors, or non-%NULL to report - * errors. An error can only occur when @exclusive is set to %TRUE and - * not all @max_threads threads could be created. - * - * Return value: the new #GThreadPool - **/ -GThreadPool* -g_thread_pool_new (GFunc func, - gpointer user_data, - gint max_threads, - gboolean exclusive, - GError **error) + * errors. An error can only occur when @exclusive is set to %TRUE + * and not all @max_threads threads could be created. + * See #GThreadError for possible errors that may occur. + * Note, even in case of error a valid #GThreadPool is returned. + * + * Returns: the new #GThreadPool + */ +GThreadPool * +g_thread_pool_new (GFunc func, + gpointer user_data, + gint max_threads, + gboolean exclusive, + GError **error) { GRealThreadPool *retval; G_LOCK_DEFINE_STATIC (init); @@ -476,7 +473,6 @@ g_thread_pool_new (GFunc func, g_return_val_if_fail (func, NULL); g_return_val_if_fail (!exclusive || max_threads != -1, NULL); g_return_val_if_fail (max_threads >= -1, NULL); - g_return_val_if_fail (g_thread_supported (), NULL); retval = g_new (GRealThreadPool, 1); @@ -484,10 +480,12 @@ g_thread_pool_new (GFunc func, retval->pool.user_data = user_data; retval->pool.exclusive = exclusive; retval->queue = g_async_queue_new (); - retval->cond = NULL; + g_cond_init (&retval->cond); retval->max_threads = max_threads; retval->num_threads = 0; retval->running = TRUE; + retval->immediate = FALSE; + retval->waiting = FALSE; retval->sort_func = NULL; retval->sort_user_data = NULL; @@ -499,17 +497,17 @@ g_thread_pool_new (GFunc func, if (retval->pool.exclusive) { g_async_queue_lock (retval->queue); - + while (retval->num_threads < retval->max_threads) - { - GError *local_error = NULL; - g_thread_pool_start_thread (retval, &local_error); - if (local_error) - { - g_propagate_error (error, local_error); - break; - } - } + { + GError *local_error = NULL; + + if (!g_thread_pool_start_thread (retval, &local_error)) + { + g_propagate_error (error, local_error); + break; + } + } g_async_queue_unlock (retval->queue); } @@ -521,102 +519,132 @@ g_thread_pool_new (GFunc func, * g_thread_pool_push: * @pool: a #GThreadPool * @data: a new task for @pool - * @error: return location for error - * - * Inserts @data into the list of tasks to be executed by @pool. When - * the number of currently running threads is lower than the maximal - * allowed number of threads, a new thread is started (or reused) with - * the properties given to g_thread_pool_new (). Otherwise @data stays - * in the queue until a thread in this pool finishes its previous task - * and processes @data. + * @error: return location for error, or %NULL + * + * Inserts @data into the list of tasks to be executed by @pool. + * + * When the number of currently running threads is lower than the + * maximal allowed number of threads, a new thread is started (or + * reused) with the properties given to g_thread_pool_new(). + * Otherwise, @data stays in the queue until a thread in this pool + * finishes its previous task and processes @data. * * @error can be %NULL to ignore errors, or non-%NULL to report * errors. An error can only occur when a new thread couldn't be - * created. In that case @data is simply appended to the queue of work - * to do. - **/ -void + * created. In that case @data is simply appended to the queue of + * work to do. + * + * Before version 2.32, this function did not return a success status. + * + * Returns: %TRUE on success, %FALSE if an error occurred + */ +gboolean g_thread_pool_push (GThreadPool *pool, - gpointer data, - GError **error) + gpointer data, + GError **error) { GRealThreadPool *real; + gboolean result; real = (GRealThreadPool*) pool; - g_return_if_fail (real); - g_return_if_fail (real->running); + g_return_val_if_fail (real, FALSE); + g_return_val_if_fail (real->running, FALSE); + + result = TRUE; g_async_queue_lock (real->queue); if (g_async_queue_length_unlocked (real->queue) >= 0) - /* No thread is waiting in the queue */ - g_thread_pool_start_thread (real, error); + { + /* No thread is waiting in the queue */ + GError *local_error = NULL; + + if (!g_thread_pool_start_thread (real, &local_error)) + { + g_propagate_error (error, local_error); + result = FALSE; + } + } g_thread_pool_queue_push_unlocked (real, data); g_async_queue_unlock (real->queue); + + return result; } /** * g_thread_pool_set_max_threads: * @pool: a #GThreadPool - * @max_threads: a new maximal number of threads for @pool - * @error: return location for error - * - * Sets the maximal allowed number of threads for @pool. A value of -1 - * means, that the maximal number of threads is unlimited. - * - * Setting @max_threads to 0 means stopping all work for @pool. It is - * effectively frozen until @max_threads is set to a non-zero value - * again. - * + * @max_threads: a new maximal number of threads for @pool, + * or -1 for unlimited + * @error: return location for error, or %NULL + * + * Sets the maximal allowed number of threads for @pool. + * A value of -1 means that the maximal number of threads + * is unlimited. If @pool is an exclusive thread pool, setting + * the maximal number of threads to -1 is not allowed. + * + * Setting @max_threads to 0 means stopping all work for @pool. + * It is effectively frozen until @max_threads is set to a non-zero + * value again. + * * A thread is never terminated while calling @func, as supplied by - * g_thread_pool_new (). Instead the maximal number of threads only - * has effect for the allocation of new threads in g_thread_pool_push(). + * g_thread_pool_new(). Instead the maximal number of threads only + * has effect for the allocation of new threads in g_thread_pool_push(). * A new thread is allocated, whenever the number of currently * running threads in @pool is smaller than the maximal number. * * @error can be %NULL to ignore errors, or non-%NULL to report * errors. An error can only occur when a new thread couldn't be - * created. - **/ -void + * created. + * + * Before version 2.32, this function did not return a success status. + * + * Returns: %TRUE on success, %FALSE if an error occurred + */ +gboolean g_thread_pool_set_max_threads (GThreadPool *pool, - gint max_threads, - GError **error) + gint max_threads, + GError **error) { GRealThreadPool *real; gint to_start; + gboolean result; real = (GRealThreadPool*) pool; - g_return_if_fail (real); - g_return_if_fail (real->running); - g_return_if_fail (!real->pool.exclusive || max_threads != -1); - g_return_if_fail (max_threads >= -1); + g_return_val_if_fail (real, FALSE); + g_return_val_if_fail (real->running, FALSE); + g_return_val_if_fail (!real->pool.exclusive || max_threads != -1, FALSE); + g_return_val_if_fail (max_threads >= -1, FALSE); + + result = TRUE; g_async_queue_lock (real->queue); real->max_threads = max_threads; - + if (pool->exclusive) to_start = real->max_threads - real->num_threads; else to_start = g_async_queue_length_unlocked (real->queue); - + for ( ; to_start > 0; to_start--) { GError *local_error = NULL; - g_thread_pool_start_thread (real, &local_error); - if (local_error) - { - g_propagate_error (error, local_error); - break; - } + if (!g_thread_pool_start_thread (real, &local_error)) + { + g_propagate_error (error, local_error); + result = FALSE; + break; + } } - + g_async_queue_unlock (real->queue); + + return result; } /** @@ -625,8 +653,8 @@ g_thread_pool_set_max_threads (GThreadPool *pool, * * Returns the maximal number of threads for @pool. * - * Return value: the maximal number of threads - **/ + * Returns: the maximal number of threads + */ gint g_thread_pool_get_max_threads (GThreadPool *pool) { @@ -651,8 +679,8 @@ g_thread_pool_get_max_threads (GThreadPool *pool) * * Returns the number of threads currently running in @pool. * - * Return value: the number of threads currently running - **/ + * Returns: the number of threads currently running + */ guint g_thread_pool_get_num_threads (GThreadPool *pool) { @@ -677,8 +705,8 @@ g_thread_pool_get_num_threads (GThreadPool *pool) * * Returns the number of tasks still unprocessed in @pool. * - * Return value: the number of unprocessed tasks - **/ + * Returns: the number of unprocessed tasks + */ guint g_thread_pool_unprocessed (GThreadPool *pool) { @@ -703,22 +731,23 @@ g_thread_pool_unprocessed (GThreadPool *pool) * * Frees all resources allocated for @pool. * - * If @immediate is %TRUE, no new task is processed for - * @pool. Otherwise @pool is not freed before the last task is - * processed. Note however, that no thread of this pool is - * interrupted, while processing a task. Instead at least all still - * running threads can finish their tasks before the @pool is freed. + * If @immediate is %TRUE, no new task is processed for @pool. + * Otherwise @pool is not freed before the last task is processed. + * Note however, that no thread of this pool is interrupted while + * processing a task. Instead at least all still running threads + * can finish their tasks before the @pool is freed. * - * If @wait_ is %TRUE, the functions does not return before all tasks - * to be processed (dependent on @immediate, whether all or only the - * currently running) are ready. Otherwise the function returns immediately. + * If @wait_ is %TRUE, the functions does not return before all + * tasks to be processed (dependent on @immediate, whether all + * or only the currently running) are ready. + * Otherwise the function returns immediately. * - * After calling this function @pool must not be used anymore. - **/ + * After calling this function @pool must not be used anymore. + */ void g_thread_pool_free (GThreadPool *pool, - gboolean immediate, - gboolean wait_) + gboolean immediate, + gboolean wait_) { GRealThreadPool *real; @@ -728,11 +757,11 @@ g_thread_pool_free (GThreadPool *pool, g_return_if_fail (real->running); /* If there's no thread allowed here, there is not much sense in - * not stopping this pool immediately, when it's not empty + * not stopping this pool immediately, when it's not empty */ - g_return_if_fail (immediate || - real->max_threads != 0 || - g_async_queue_length (real->queue) == 0); + g_return_if_fail (immediate || + real->max_threads != 0 || + g_async_queue_length (real->queue) == 0); g_async_queue_lock (real->queue); @@ -742,31 +771,29 @@ g_thread_pool_free (GThreadPool *pool, if (wait_) { - real->cond = g_cond_new (); - while (g_async_queue_length_unlocked (real->queue) != -real->num_threads && - !(immediate && real->num_threads == 0)) - g_cond_wait (real->cond, _g_async_queue_get_mutex (real->queue)); + !(immediate && real->num_threads == 0)) + g_cond_wait (&real->cond, _g_async_queue_get_mutex (real->queue)); } if (immediate || g_async_queue_length_unlocked (real->queue) == -real->num_threads) { /* No thread is currently doing something (and nothing is left - * to process in the queue) + * to process in the queue) */ - if (real->num_threads == 0) - { - /* No threads left, we clean up */ - g_async_queue_unlock (real->queue); - g_thread_pool_free_internal (real); - return; - } + if (real->num_threads == 0) + { + /* No threads left, we clean up */ + g_async_queue_unlock (real->queue); + g_thread_pool_free_internal (real); + return; + } g_thread_pool_wakeup_and_stop_all (real); } - + /* The last thread should cleanup the pool */ - real->waiting = FALSE; + real->waiting = FALSE; g_async_queue_unlock (real->queue); } @@ -778,40 +805,46 @@ g_thread_pool_free_internal (GRealThreadPool* pool) g_return_if_fail (pool->num_threads == 0); g_async_queue_unref (pool->queue); - - if (pool->cond) - g_cond_free (pool->cond); + g_cond_clear (&pool->cond); g_free (pool); } static void -g_thread_pool_wakeup_and_stop_all (GRealThreadPool* pool) +g_thread_pool_wakeup_and_stop_all (GRealThreadPool *pool) { guint i; - + g_return_if_fail (pool); g_return_if_fail (pool->running == FALSE); g_return_if_fail (pool->num_threads != 0); - pool->immediate = TRUE; + pool->immediate = TRUE; + /* + * So here we're sending bogus data to the pool threads, which + * should cause them each to wake up, and check the above + * pool->immediate condition. However we don't want that + * data to be sorted (since it'll crash the sorter). + */ for (i = 0; i < pool->num_threads; i++) - g_thread_pool_queue_push_unlocked (pool, GUINT_TO_POINTER (1)); + g_async_queue_push_unlocked (pool->queue, GUINT_TO_POINTER (1)); } /** * g_thread_pool_set_max_unused_threads: * @max_threads: maximal number of unused threads * - * Sets the maximal number of unused threads to @max_threads. If - * @max_threads is -1, no limit is imposed on the number of unused - * threads. - **/ + * Sets the maximal number of unused threads to @max_threads. + * If @max_threads is -1, no limit is imposed on the number + * of unused threads. + * + * The default value is 2. + */ void g_thread_pool_set_max_unused_threads (gint max_threads) { - g_return_if_fail (max_threads >= -1); + g_return_if_fail (max_threads >= -1); g_atomic_int_set (&max_unused_threads, max_threads); @@ -819,31 +852,31 @@ g_thread_pool_set_max_unused_threads (gint max_threads) { max_threads -= g_atomic_int_get (&unused_threads); if (max_threads < 0) - { - g_atomic_int_set (&kill_unused_threads, -max_threads); - g_atomic_int_inc (&wakeup_thread_serial); + { + g_atomic_int_set (&kill_unused_threads, -max_threads); + g_atomic_int_inc (&wakeup_thread_serial); - g_async_queue_lock (unused_thread_queue); + g_async_queue_lock (unused_thread_queue); - do - { - g_async_queue_push_unlocked (unused_thread_queue, - wakeup_thread_marker); - } - while (++max_threads); + do + { + g_async_queue_push_unlocked (unused_thread_queue, + wakeup_thread_marker); + } + while (++max_threads); - g_async_queue_unlock (unused_thread_queue); - } + g_async_queue_unlock (unused_thread_queue); + } } } /** * g_thread_pool_get_max_unused_threads: - * + * * Returns the maximal allowed number of unused threads. * - * Return value: the maximal number of unused threads - **/ + * Returns: the maximal number of unused threads + */ gint g_thread_pool_get_max_unused_threads (void) { @@ -852,12 +885,12 @@ g_thread_pool_get_max_unused_threads (void) /** * g_thread_pool_get_num_unused_threads: - * + * * Returns the number of currently unused threads. * - * Return value: the number of currently unused threads - **/ -guint + * Returns: the number of currently unused threads + */ +guint g_thread_pool_get_num_unused_threads (void) { return g_atomic_int_get (&unused_threads); @@ -865,14 +898,14 @@ g_thread_pool_get_num_unused_threads (void) /** * g_thread_pool_stop_unused_threads: - * + * * Stops all currently unused threads. This does not change the * maximal number of unused threads. This function can be used to * regularly stop all unused threads e.g. from g_timeout_add(). - **/ + */ void g_thread_pool_stop_unused_threads (void) -{ +{ guint oldval; oldval = g_thread_pool_get_max_unused_threads (); @@ -884,31 +917,31 @@ g_thread_pool_stop_unused_threads (void) /** * g_thread_pool_set_sort_function: * @pool: a #GThreadPool - * @func: the #GCompareDataFunc used to sort the list of tasks. + * @func: the #GCompareDataFunc used to sort the list of tasks. * This function is passed two tasks. It should return - * 0 if the order in which they are handled does not matter, + * 0 if the order in which they are handled does not matter, * a negative value if the first task should be processed before - * the second or a positive value if the second task should be + * the second or a positive value if the second task should be * processed first. - * @user_data: user data passed to @func. + * @user_data: user data passed to @func * * Sets the function used to sort the list of tasks. This allows the * tasks to be processed by a priority determined by @func, and not * just in the order in which they were added to the pool. * * Note, if the maximum number of threads is more than 1, the order - * that threads are executed can not be guranteed 100%. Threads are + * that threads are executed cannot be guaranteed 100%. Threads are * scheduled by the operating system and are executed at random. It * cannot be assumed that threads are executed in the order they are - * created. + * created. * * Since: 2.10 - **/ -void + */ +void g_thread_pool_set_sort_function (GThreadPool *pool, - GCompareDataFunc func, - gpointer user_data) -{ + GCompareDataFunc func, + gpointer user_data) +{ GRealThreadPool *real; real = (GRealThreadPool*) pool; @@ -920,36 +953,35 @@ g_thread_pool_set_sort_function (GThreadPool *pool, real->sort_func = func; real->sort_user_data = user_data; - - if (func) - g_async_queue_sort_unlocked (real->queue, - real->sort_func, - real->sort_user_data); + + if (func) + g_async_queue_sort_unlocked (real->queue, + real->sort_func, + real->sort_user_data); g_async_queue_unlock (real->queue); } /** * g_thread_pool_set_max_idle_time: - * @interval: the maximum @interval (1/1000ths of a second) a thread - * can be idle. + * @interval: the maximum @interval (in milliseconds) + * a thread can be idle * - * This function will set the maximum @interval that a thread waiting - * in the pool for new tasks can be idle for before being - * stopped. This function is similar to calling - * g_thread_pool_stop_unused_threads() on a regular timeout, except, - * this is done on a per thread basis. + * This function will set the maximum @interval that a thread + * waiting in the pool for new tasks can be idle for before + * being stopped. This function is similar to calling + * g_thread_pool_stop_unused_threads() on a regular timeout, + * except this is done on a per thread basis. * * By setting @interval to 0, idle threads will not be stopped. - * - * This function makes use of g_async_queue_timed_pop () using - * @interval. + * + * The default value is 15000 (15 seconds). * * Since: 2.10 - **/ + */ void g_thread_pool_set_max_idle_time (guint interval) -{ +{ guint i; g_atomic_int_set (&max_idle_time, interval); @@ -961,10 +993,10 @@ g_thread_pool_set_max_idle_time (guint interval) g_async_queue_lock (unused_thread_queue); do - { - g_async_queue_push_unlocked (unused_thread_queue, - wakeup_thread_marker); - } + { + g_async_queue_push_unlocked (unused_thread_queue, + wakeup_thread_marker); + } while (--i); g_async_queue_unlock (unused_thread_queue); @@ -973,23 +1005,22 @@ g_thread_pool_set_max_idle_time (guint interval) /** * g_thread_pool_get_max_idle_time: - * - * This function will return the maximum @interval that a thread will - * wait in the thread pool for new tasks before being stopped. * - * If this function returns 0, threads waiting in the thread pool for - * new work are not stopped. + * This function will return the maximum @interval that a + * thread will wait in the thread pool for new tasks before + * being stopped. + * + * If this function returns 0, threads waiting in the thread + * pool for new work are not stopped. + * + * Returns: the maximum @interval (milliseconds) to wait + * for new tasks in the thread pool before stopping the + * thread * - * Return value: the maximum @interval to wait for new tasks in the - * thread pool before stopping the thread (1/1000ths of a second). - * * Since: 2.10 - **/ + */ guint g_thread_pool_get_max_idle_time (void) -{ +{ return g_atomic_int_get (&max_idle_time); } - -#define __G_THREADPOOL_C__ -#include "galiasdef.c"