[PATCH v3 08/10] perf auxtrace: Use WRITE_ONCE() for updating aux_tail

[Leo Yan]

Use WRITE_ONCE() for updating aux_tail, so can avoid unexpected memory
behaviour.

Signed-off-by: Leo Yan <leo.yan@xxxxxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 tools/perf/util/auxtrace.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/auxtrace.h b/tools/perf/util/auxtrace.h
index 1a2f42980e3f..d68a5e80b217 100644
--- a/tools/perf/util/auxtrace.h
+++ b/tools/perf/util/auxtrace.h
@@ -456,7 +456,7 @@ 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();
-	pc->aux_tail = tail;
+	WRITE_ONCE(pc->aux_tail, tail);
 }
 
 int auxtrace_mmap__mmap(struct auxtrace_mmap *mm,
-- 
2.25.1