From: Yucong Sun <sunyucong@gmail.com>
Date: Wed, 6 Oct 2021 18:56:11 +0000 (-0700)
Subject: selftests/bpf: Fix race condition in enable_stats
X-Git-Tag: v6.6.17~8953^2~2^2~62^2~4
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d719de0d2f3cbdb5890a147b90a51c5eaaef103e;p=platform%2Fkernel%2Flinux-rpi.git

selftests/bpf: Fix race condition in enable_stats

In parallel execution mode, this test now need to use atomic operation
to avoid race condition.

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211006185619.364369-7-fallentree@fb.com
---

diff --git a/tools/testing/selftests/bpf/progs/test_enable_stats.c b/tools/testing/selftests/bpf/progs/test_enable_stats.c
index 01a002a..1705097 100644
--- a/tools/testing/selftests/bpf/progs/test_enable_stats.c
+++ b/tools/testing/selftests/bpf/progs/test_enable_stats.c
@@ -13,6 +13,6 @@ __u64 count = 0;
 SEC("raw_tracepoint/sys_enter")
 int test_enable_stats(void *ctx)
 {
-	count += 1;
+	__sync_fetch_and_add(&count, 1);
 	return 0;
 }