The count variable is incremented by multiple threads, doing so
without an atomic operation causes thread sanitizer warnings. Switch
to using relaxed atomics.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/tests/workloads/thloop.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/tests/workloads/thloop.c b/tools/perf/tests/workloads/thloop.c
index 29193b75717e..af05269c2eb8 100644
--- a/tools/perf/tests/workloads/thloop.c
+++ b/tools/perf/tests/workloads/thloop.c
@@ -20,7 +20,7 @@ static void sighandler(int sig __maybe_unused)
 noinline void test_loop(void)
 {
 	while (!done)
-		count++;
+		__atomic_fetch_add(&count, 1, __ATOMIC_RELAXED);
 }
 
 static void *thfunc(void *arg)
-- 
2.39.0.314.g84b9a713c41-goog

On Sat, Jan 14, 2023 at 1:53 PM Ian Rogers <irogers@google.com> wrote:
>
> The count variable is incremented by multiple threads, doing so
> without an atomic operation causes thread sanitizer warnings. Switch
> to using relaxed atomics.
>
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  tools/perf/tests/workloads/thloop.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/tests/workloads/thloop.c b/tools/perf/tests/workloads/thloop.c
> index 29193b75717e..af05269c2eb8 100644
> --- a/tools/perf/tests/workloads/thloop.c
> +++ b/tools/perf/tests/workloads/thloop.c
> @@ -20,7 +20,7 @@ static void sighandler(int sig __maybe_unused)
>  noinline void test_loop(void)
>  {
>         while (!done)
> -               count++;
> +               __atomic_fetch_add(&count, 1, __ATOMIC_RELAXED);

Ping. No functional change, cleans up a lot of thread sanitizer
issues, the use of __atomic_fetch_add is consistent with other files.

Thanks,
Ian

>  }
>
>  static void *thfunc(void *arg)
> --
> 2.39.0.314.g84b9a713c41-goog
>