[Mesa-dev] [PATCH 5/7] util/queue: hold a lock when reading num_threads in util_queue_finish

[Marek Olšák]

From: Marek Olšák <marek.olsak at amd.com>

Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>
---
 src/util/u_queue.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/util/u_queue.c b/src/util/u_queue.c
index cfd2a08e3c8..5e0c1095569 100644
--- a/src/util/u_queue.c
+++ b/src/util/u_queue.c
@@ -585,29 +585,29 @@ util_queue_finish_execute(void *data, int num_thread)
    util_barrier_wait(barrier);
 }
 
 /**
  * Wait until all previously added jobs have completed.
  */
 void
 util_queue_finish(struct util_queue *queue)
 {
    util_barrier barrier;
-   struct util_queue_fence *fences = malloc(queue->num_threads * sizeof(*fences));
-
-   util_barrier_init(&barrier, queue->num_threads);
+   struct util_queue_fence *fences;
 
    /* If 2 threads were adding jobs for 2 different barries at the same time,
     * a deadlock would happen, because 1 barrier requires that all threads
     * wait for it exclusively.
     */
    mtx_lock(&queue->finish_lock);
+   fences = malloc(queue->num_threads * sizeof(*fences));
+   util_barrier_init(&barrier, queue->num_threads);
 
    for (unsigned i = 0; i < queue->num_threads; ++i) {
       util_queue_fence_init(&fences[i]);
       util_queue_add_job(queue, &barrier, &fences[i], util_queue_finish_execute, NULL);
    }
 
    for (unsigned i = 0; i < queue->num_threads; ++i) {
       util_queue_fence_wait(&fences[i]);
       util_queue_fence_destroy(&fences[i]);
    }
-- 
2.17.1