2021-06-02 10:32:38

by Leo Yan

[permalink] [raw]
Subject: [PATCH v2 4/8] perf/x86: Add barrier after updating bts

Add barrier wmb() to separate the AUX data store and aux_head store.

Signed-off-by: Leo Yan <[email protected]>
---
arch/x86/events/intel/bts.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/x86/events/intel/bts.c b/arch/x86/events/intel/bts.c
index 6320d2cfd9d3..4a015d160bc5 100644
--- a/arch/x86/events/intel/bts.c
+++ b/arch/x86/events/intel/bts.c
@@ -209,6 +209,9 @@ static void bts_update(struct bts_ctx *bts)
} else {
local_set(&buf->data_size, head);
}
+
+ /* The WMB separates data store and aux_head store matches. */
+ wmb();
}

static int
--
2.25.1