Add threadpool options and accompanying test.

The only test added so far is an idle thread timeout
option. This will greatly aid threadpool users who wish
to maintain a threadpool by allowing for idle threads to
die out as necessary.

Test passes.



git-svn-id: https://origsvn.digium.com/svn/asterisk/team/mmichelson/threadpool@377580 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 56 insertions, 3 deletions

diff --git a/main/threadpool.c b/main/threadpool.c
index 45e863805..18c1349ae 100644
--- a/main/threadpool.c
+++ b/main/threadpool.c
@@ -95,6 +95,8 @@ struct ast_threadpool {
 	struct ast_taskprocessor *control_tps;
 	/*! True if the threadpool is in the processof shutting down */
 	int shutting_down;
+	/*! Threadpool-specific options */
+	struct ast_threadpool_options options;
 };
 
 /*!
@@ -266,6 +268,32 @@ static void threadpool_zombie_thread_dead(struct ast_threadpool *pool,
 	ast_taskprocessor_push(pool->control_tps, queued_zombie_thread_dead, pair);
 }
 
+static int queued_idle_thread_dead(void *data)
+{
+	struct thread_worker_pair *pair = data;
+
+	ao2_unlink(pair->pool->idle_threads, pair->worker);
+	threadpool_send_state_changed(pair->pool);
+
+	ao2_ref(pair, -1);
+	return 0;
+}
+
+static void threadpool_idle_thread_dead(struct ast_threadpool *pool,
+		struct worker_thread *worker)
+{
+	struct thread_worker_pair *pair;
+	SCOPED_AO2LOCK(lock, pool);
+	if (pool->shutting_down) {
+		return;
+	}
+	pair = thread_worker_pair_alloc(pool, worker);
+	if (!pair) {
+		return;
+	}
+	ast_taskprocessor_push(pool->control_tps, queued_idle_thread_dead, pair);
+}
+
 /*!
  * \brief Execute a task in the threadpool
  * 
@@ -749,7 +777,13 @@ struct ast_threadpool_listener *ast_threadpool_listener_alloc(
 	return listener;
 }
 
-struct ast_threadpool *ast_threadpool_create(struct ast_threadpool_listener *listener, int initial_size)
+struct pool_options_pair {
+	struct ast_threadpool *pool;
+	struct ast_threadpool_options options;
+};
+
+struct ast_threadpool *ast_threadpool_create(struct ast_threadpool_listener *listener,
+		int initial_size, const struct ast_threadpool_options *options)
 {
 	struct ast_threadpool *pool;
 	struct ast_taskprocessor *tps;
@@ -771,6 +805,7 @@ struct ast_threadpool *ast_threadpool_create(struct ast_threadpool_listener *lis
 	pool->tps = tps;
 	ao2_ref(listener, +1);
 	pool->listener = listener;
+	pool->options = *options;
 	ast_threadpool_set_size(pool, initial_size);
 	return pool;
 }
@@ -814,6 +849,8 @@ struct worker_thread {
 	enum worker_state state;
 	/*! A boolean used to determine if an idle thread should become active */
 	int wake_up;
+	/*! Options for this threadpool */
+	struct ast_threadpool_options options;
 };
 
 /*!
@@ -864,7 +901,7 @@ static void worker_shutdown(struct worker_thread *worker)
 static void worker_thread_destroy(void *obj)
 {
 	struct worker_thread *worker = obj;
-	ast_log(LOG_NOTICE, "Worker dying\n");
+	ast_debug(1, "Destroying worker thread\n");
 	worker_shutdown(worker);
 	ast_mutex_destroy(&worker->lock);
 	ast_cond_destroy(&worker->cond);
@@ -909,6 +946,7 @@ static struct worker_thread *worker_thread_alloc(struct ast_threadpool *pool)
 	worker->pool = pool;
 	worker->thread = AST_PTHREADT_NULL;
 	worker->state = ALIVE;
+	worker->options = pool->options;
 	if (ast_pthread_create(&worker->thread, NULL, worker_start, worker) < 0) {
 		ast_log(LOG_ERROR, "Unable to start worker thread!\n");
 		ao2_ref(worker, -1);
@@ -961,13 +999,28 @@ static void worker_active(struct worker_thread *worker)
  */
 static int worker_idle(struct worker_thread *worker)
 {
+	struct timeval start = ast_tvnow();
+	struct timespec end = {
+		.tv_sec = start.tv_sec + worker->options.idle_timeout,
+		.tv_nsec = start.tv_usec * 1000,
+	};
 	SCOPED_MUTEX(lock, &worker->lock);
 	if (worker->state != ALIVE) {
 		return 0;
 	}
 	threadpool_active_thread_idle(worker->pool, worker);
 	while (!worker->wake_up) {
-		ast_cond_wait(&worker->cond, lock);
+		if (worker->options.idle_timeout <= 0) {
+			ast_cond_wait(&worker->cond, lock);
+		} else if (ast_cond_timedwait(&worker->cond, lock, &end) == ETIMEDOUT) {
+			break;
+		}
+	}
+
+	if (!worker->wake_up) {
+		ast_debug(1, "Worker thread idle timeout reached. Dying.\n");
+		threadpool_idle_thread_dead(worker->pool, worker);
+		worker->state = DEAD;
 	}
 	worker->wake_up = 0;
 	return worker->state == ALIVE;