diff --git a/libavutil/threadmessage.c b/libavutil/threadmessage.c index b7d7dadb5a..1f2cca8668 100644 --- a/libavutil/threadmessage.c +++ b/libavutil/threadmessage.c @@ -36,7 +36,8 @@ struct AVThreadMessageQueue { #if HAVE_THREADS AVFifoBuffer *fifo; pthread_mutex_t lock; - pthread_cond_t cond; + pthread_cond_t cond_recv; + pthread_cond_t cond_send; int err_send; int err_recv; unsigned elsize; @@ -62,13 +63,20 @@ int av_thread_message_queue_alloc(AVThreadMessageQueue **mq, av_free(rmq); return AVERROR(ret); } - if ((ret = pthread_cond_init(&rmq->cond, NULL))) { + if ((ret = pthread_cond_init(&rmq->cond_recv, NULL))) { + pthread_mutex_destroy(&rmq->lock); + av_free(rmq); + return AVERROR(ret); + } + if ((ret = pthread_cond_init(&rmq->cond_send, NULL))) { + pthread_cond_destroy(&rmq->cond_recv); pthread_mutex_destroy(&rmq->lock); av_free(rmq); return AVERROR(ret); } if (!(rmq->fifo = av_fifo_alloc(elsize * nelem))) { - pthread_cond_destroy(&rmq->cond); + pthread_cond_destroy(&rmq->cond_send); + pthread_cond_destroy(&rmq->cond_recv); pthread_mutex_destroy(&rmq->lock); av_free(rmq); return AVERROR(ret); @@ -94,7 +102,8 @@ void av_thread_message_queue_free(AVThreadMessageQueue **mq) if (*mq) { av_thread_message_flush(*mq); av_fifo_freep(&(*mq)->fifo); - pthread_cond_destroy(&(*mq)->cond); + pthread_cond_destroy(&(*mq)->cond_send); + pthread_cond_destroy(&(*mq)->cond_recv); pthread_mutex_destroy(&(*mq)->lock); av_freep(mq); } @@ -110,12 +119,13 @@ static int av_thread_message_queue_send_locked(AVThreadMessageQueue *mq, while (!mq->err_send && av_fifo_space(mq->fifo) < mq->elsize) { if ((flags & AV_THREAD_MESSAGE_NONBLOCK)) return AVERROR(EAGAIN); - pthread_cond_wait(&mq->cond, &mq->lock); + pthread_cond_wait(&mq->cond_send, &mq->lock); } if (mq->err_send) return mq->err_send; av_fifo_generic_write(mq->fifo, msg, mq->elsize, NULL); - pthread_cond_signal(&mq->cond); + /* one message is sent, signal one receiver */ + pthread_cond_signal(&mq->cond_recv); return 0; } @@ -126,12 +136,13 @@ static int av_thread_message_queue_recv_locked(AVThreadMessageQueue *mq, while (!mq->err_recv && av_fifo_size(mq->fifo) < mq->elsize) { if ((flags & AV_THREAD_MESSAGE_NONBLOCK)) return AVERROR(EAGAIN); - pthread_cond_wait(&mq->cond, &mq->lock); + pthread_cond_wait(&mq->cond_recv, &mq->lock); } if (av_fifo_size(mq->fifo) < mq->elsize) return mq->err_recv; av_fifo_generic_read(mq->fifo, msg, mq->elsize, NULL); - pthread_cond_signal(&mq->cond); + /* one message space appeared, signal one sender */ + pthread_cond_signal(&mq->cond_send); return 0; } @@ -175,7 +186,7 @@ void av_thread_message_queue_set_err_send(AVThreadMessageQueue *mq, #if HAVE_THREADS pthread_mutex_lock(&mq->lock); mq->err_send = err; - pthread_cond_broadcast(&mq->cond); + pthread_cond_broadcast(&mq->cond_send); pthread_mutex_unlock(&mq->lock); #endif /* HAVE_THREADS */ } @@ -186,7 +197,7 @@ void av_thread_message_queue_set_err_recv(AVThreadMessageQueue *mq, #if HAVE_THREADS pthread_mutex_lock(&mq->lock); mq->err_recv = err; - pthread_cond_broadcast(&mq->cond); + pthread_cond_broadcast(&mq->cond_recv); pthread_mutex_unlock(&mq->lock); #endif /* HAVE_THREADS */ } @@ -209,7 +220,9 @@ void av_thread_message_flush(AVThreadMessageQueue *mq) for (off = 0; off < used; off += mq->elsize) av_fifo_generic_peek_at(mq->fifo, mq, off, mq->elsize, free_func_wrap); av_fifo_drain(mq->fifo, used); - pthread_cond_broadcast(&mq->cond); + /* only the senders need to be notified since the queue is empty and there + * is nothing to read */ + pthread_cond_broadcast(&mq->cond_send); pthread_mutex_unlock(&mq->lock); #endif /* HAVE_THREADS */ }