multiqueue: don't lock multiqueue when pushing serialized queries

If we are pushing a serialized query into a queue and the queue is
filled, we will end in a deadlock. We need to release the lock before
pushing and acquire it again afterward.

https://bugzilla.gnome.org/show_bug.cgi?id=737794
This commit is contained in:
Aleix Conchillo Flaqué 2014-10-08 09:37:41 -07:00 committed by Sebastian Dröge
parent 33e65d9358
commit 41fa9ad9f2

View file

@ -171,6 +171,7 @@ struct _GstSingleQueue
/* for serialized queries */
GCond query_handled;
gboolean last_query;
GstQuery *last_handled_query;
};
@ -1268,6 +1269,7 @@ gst_single_queue_push_one (GstMultiQueue * mq, GstSingleQueue * sq,
GST_MULTI_QUEUE_MUTEX_LOCK (mq);
sq->last_query = res;
sq->last_handled_query = query;
g_cond_signal (&sq->query_handled);
GST_MULTI_QUEUE_MUTEX_UNLOCK (mq);
} else {
@ -1861,9 +1863,19 @@ gst_multi_queue_sink_query (GstPad * pad, GstObject * parent, GstQuery * query)
GST_DEBUG_OBJECT (mq,
"SingleQueue %d : Enqueuing query %p of type %s with id %d",
sq->id, query, GST_QUERY_TYPE_NAME (query), curid);
GST_MULTI_QUEUE_MUTEX_UNLOCK (mq);
res = gst_data_queue_push (sq->queue, (GstDataQueueItem *) item);
g_cond_wait (&sq->query_handled, &mq->qlock);
GST_MULTI_QUEUE_MUTEX_LOCK (mq);
/* it might be that the query has been taken out of the queue
* while we were unlocked. So, we need to check if the last
* handled query is the same one than the one we just
* pushed. If it is, we don't need to wait for the condition
* variable, otherwise we wait for the condition variable to
* be signaled. */
if (sq->last_handled_query != query)
g_cond_wait (&sq->query_handled, &mq->qlock);
res = sq->last_query;
sq->last_handled_query = NULL;
} else {
GST_DEBUG_OBJECT (mq, "refusing query, we are buffering and the "
"queue is not empty");