X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=ao_write.c;h=5c14aa719af937a4aba4a3a8efd62078c86bef6d;hp=a2e86ed258c5857ff10014ea99d1335009e2a97b;hb=bc4fabf9e706f28897ab5c1068a97564f3378750;hpb=d2c65fd068a5c2e7cde52bd06e1eadc7e7e37364

diff --git a/ao_write.c b/ao_write.c
index a2e86ed2..5c14aa71 100644
--- a/ao_write.c
+++ b/ao_write.c
@@ -28,6 +28,7 @@ struct private_aow_data {
 
 	pthread_t thread;
 	pthread_attr_t attr;
+	/* The mutex and the condition variable serialize access to ->btrn */
 	pthread_mutex_t mutex;
 	pthread_cond_t data_available;
 	struct btr_node *thread_btrn;
@@ -39,6 +40,10 @@ static void aow_close(struct writer_node *wn)
 
 	if (!pawd)
 		return;
+	if (pawd->thread_btrn) {
+		pthread_cancel(pawd->thread);
+		pthread_join(pawd->thread, NULL);
+	}
 	ao_close(pawd->dev);
 	free(pawd);
 	wn->private_data = NULL;
@@ -220,10 +225,6 @@ __noreturn static void *aow_play(void *priv)
 	int ret;
 
 	for (;;) {
-		/*
-		 * Lock mutex and wait for signal. pthread_cond_wait() will
-		 * automatically and atomically unlock mutex while it waits.
-		 */
 		pthread_mutex_lock(&pawd->mutex);
 		for (;;) {
 			ret = btr_node_status(btrn, wn->min_iqs, BTR_NT_LEAF);
@@ -239,10 +240,16 @@ __noreturn static void *aow_play(void *priv)
 				ret = -E_WRITE_COMMON_EOF;
 				goto unlock;
 			}
-			//PARA_CRIT_LOG("waiting for data\n");
-			//usleep(1000);
-			//pthread_mutex_unlock(&pawd->mutex);
-			pthread_cond_wait(&pawd->data_available, &pawd->mutex);
+			/*
+			 * No data available, go to sleep and wait for the main
+			 * thread to wake us up. pthread_cond_wait() unlocks
+			 * the mutex while it waits and locks it again upon
+			 * return.
+			 */
+			ret = pthread_cond_wait(&pawd->data_available,
+				&pawd->mutex);
+			/* pthread_cond_wait() can never fail here */
+			assert(ret == 0);
 		}
 		pthread_mutex_unlock(&pawd->mutex);
 		assert(frames > 0);
@@ -354,12 +361,16 @@ static int aow_post_select(__a_unused struct sched *s,
 	ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
 	if (ret > 0) {
 		btr_pushdown(wn->btrn);
-		pthread_cond_signal(&pawd->data_available);
+		if (pthread_cond_signal(&pawd->data_available) != 0) {
+			ret = -E_AO_PTHREAD;
+			PARA_ERROR_LOG("pthread_cond_signal() failed\n");
+			goto remove_thread_btrn;
+		}
 	}
-	pthread_mutex_unlock(&pawd->mutex);
-	if (ret >= 0)
+	if (ret >= 0) {
+		pthread_mutex_unlock(&pawd->mutex);
 		goto out;
-	pthread_mutex_lock(&pawd->mutex);
+	}
 	btr_remove_node(&wn->btrn);
 	pthread_cond_signal(&pawd->data_available);
 	pthread_mutex_unlock(&pawd->mutex);