Re: [PATCH v1] perf test: Fix hybrid testing of event fallback test

[Namhyung Kim <namhyung@kernel.org>]

On Mon, Dec 01, 2025 at 03:11:36PM -0800, Ian Rogers wrote:
> The mem-loads-aux event exists on hybrid systems but the "cpu" PMU
> does not. This causes an event parsing error which erroneously makes
> the test look like it is failing. Avoid naming the PMU to avoid
> this. Rather than cleaning up perf.data in the directory the test is
> run, explicitly send the 'perf record' output to /dev/null and avoid
> any cleanup scripts.
> 
> Fixes: fc9c17b22352 ("perf test: Add a perf event fallback test")
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  .../tests/shell/test_event_open_fallback.sh   | 19 ++-----------------
>  1 file changed, 2 insertions(+), 17 deletions(-)
> 
> diff --git a/tools/perf/tests/shell/test_event_open_fallback.sh b/tools/perf/tests/shell/test_event_open_fallback.sh
> index 9c411153c01b..9420a7557c13 100755
> --- a/tools/perf/tests/shell/test_event_open_fallback.sh
> +++ b/tools/perf/tests/shell/test_event_open_fallback.sh
> @@ -6,24 +6,9 @@ skip_cnt=0
>  ok_cnt=0
>  err_cnt=0
>  
> -cleanup()
> -{
> -	rm -f perf.data
> -	rm -f perf.data.old
> -	trap - EXIT TERM INT
> -}
> -
> -trap_cleanup()
> -{
> -	cleanup
> -	exit 1
> -}
> -
> -trap trap_cleanup EXIT TERM INT
> -
>  perf_record()
>  {
> -	perf record "$@" -- true 1>/dev/null 2>&1
> +	perf record -o /dev/null "$@" -- true 1>/dev/null 2>&1
>  }
>  
>  test_decrease_precise_ip()
> @@ -49,7 +34,7 @@ test_decrease_precise_ip_complicated()
>  
>  	perf list pmu | grep -q 'mem-loads-aux' || return 2
>  
> -	if ! perf_record -e '{cpu/mem-loads-aux/S,cpu/mem-loads/PS}'; then
> +	if ! perf_record -e '{mem-loads-aux:S,mem-loads:PS}'; then

I think we need to either keep the trap handler or convert all perf
record commands including this to use -o /dev/null.

Thanks,
Namhyung


>  		return 1
>  	fi
>  	return 0
> -- 
> 2.52.0.158.g65b55ccf14-goog
>