diff mbox series

[v4,05/11] perf auxtrace: Use WRITE_ONCE() for updating aux_tail

Message ID 20210711104105.505728-6-leo.yan@linaro.org (mailing list archive)
State New, archived
Headers show
Series perf: Refine barriers for AUX ring buffer | expand

Commit Message

Leo Yan July 11, 2021, 10:40 a.m. UTC 
Use WRITE_ONCE() for updating aux_tail, so can avoid unexpected memory
behaviour.

Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
 tools/perf/util/auxtrace.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/tools/perf/util/auxtrace.h b/tools/perf/util/auxtrace.h
index cc1c1b9cec9c..79227b8864cd 100644
--- a/tools/perf/util/auxtrace.h
+++ b/tools/perf/util/auxtrace.h
@@ -480,7 +480,7 @@  static inline void auxtrace_mmap__write_tail(struct auxtrace_mmap *mm, u64 tail)
 	/* Ensure all reads are done before we write the tail out */
 	smp_mb();
 #if BITS_PER_LONG == 64 || !defined(HAVE_SYNC_COMPARE_AND_SWAP_SUPPORT)
-	pc->aux_tail = tail;
+	WRITE_ONCE(pc->aux_tail, tail);
 #else
 	do {
 		old_tail = __sync_val_compare_and_swap(&pc->aux_tail, 0, 0);