Commit-ID: f971e511cb7d6f1b3730248cf2967d3ccdd8874c
Gitweb: https://git.kernel.org/tip/f971e511cb7d6f1b3730248cf2967d3ccdd8874c
Author: Mark Rutland <[email protected]>
AuthorDate: Mon, 27 Nov 2017 10:38:21 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Tue, 12 Dec 2017 13:22:09 +0100
tools/perf: Convert ACCESS_ONCE() to READ_ONCE()
Recently there was a treewide conversion of ACCESS_ONCE() to
{READ,WRITE}_ONCE(), but a new use was introduced concurrently by
commit:
1695849735752d2a ("perf mmap: Move perf_mmap and methods to separate
mmap.[ch] files")
Let's convert this over to READ_ONCE() so that we can remove the
ACCESS_ONCE() definitions in subsequent patches.
Tested-by: Paul E. McKenney <[email protected]>
Signed-off-by: Mark Rutland <[email protected]>
Reviewed-by: Paul E. McKenney <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Joe Perches <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
tools/perf/util/mmap.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h
index efd78b8..3a5cb5a 100644
--- a/tools/perf/util/mmap.h
+++ b/tools/perf/util/mmap.h
@@ -70,7 +70,7 @@ void perf_mmap__read_catchup(struct perf_mmap *md);
static inline u64 perf_mmap__read_head(struct perf_mmap *mm)
{
struct perf_event_mmap_page *pc = mm->base;
- u64 head = ACCESS_ONCE(pc->data_head);
+ u64 head = READ_ONCE(pc->data_head);
rmb();
return head;
}
