Re: [PATCH i-g-t] syncobj_timeline: Tell the compiler to read from the thread

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 06/08/2020 18:19, Chris Wilson wrote:
32bits-limit waits for the thread to indicate it has started by busy
spinning on a common variable. The compiler is clever and knows that the
variable cannot change within the thread, and turns it into an infinite
loop!

Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx>


Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx>

---
  tests/syncobj_timeline.c | 6 ++++--
  1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tests/syncobj_timeline.c b/tests/syncobj_timeline.c
index be7dd2d1c..20375cdd3 100644
--- a/tests/syncobj_timeline.c
+++ b/tests/syncobj_timeline.c
@@ -1245,9 +1245,11 @@ test_32bits_limit(int fd)
  	uint64_t value, last_value;
  	int i;
- igt_assert_eq(pthread_create(&thread, NULL, checker_thread_func, &thread_data), 0);
+	igt_assert_eq(pthread_create(&thread, NULL,
+				     checker_thread_func, &thread_data), 0);
- while (!thread_data.started);
+	while (!READ_ONCE(thread_data.started))
+		;
for (i = 0; i < ARRAY_SIZE(points); i++) {
  		int fence = sw_sync_timeline_create_fence(timeline, i + 1);


_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx



[Index of Archives]     [AMD Graphics]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux