[Mesa-dev] [PATCH 1/2] gallium/u_queue: guard fence->signalled checks with fence->mutex
nhaehnle at gmail.com
Sat Jul 9 17:44:56 UTC 2016
From: Nicolai Hähnle <nicolai.haehnle at amd.com>
I have seen a hang during application shutdown that could be explained by the
following race condition which this patch fixes:
1. Worker thread enters util_queue_fence_signal, sets fence->signalled = true.
2. Main thread calls util_queue_job_wait, which returns immediately.
3. Main thread deletes the job and fence structures, leaving garbage behind.
4. Worker thread calls pipe_condvar_broadcast, which gets stuck forever because
it is accessing garbage.
src/gallium/auxiliary/util/u_queue.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/src/gallium/auxiliary/util/u_queue.c b/src/gallium/auxiliary/util/u_queue.c
index 627c08a..2429336 100644
@@ -41,9 +41,6 @@ util_queue_fence_signal(struct util_queue_fence *fence)
util_queue_job_wait(struct util_queue_fence *fence)
- if (fence->signalled)
More information about the mesa-dev