Re: [PATCH 2/3] perf test: Fix perf stat bpf counters test on Intel

[Song Liu]

On Fri, Aug 25, 2023 at 9:41 AM Namhyung Kim <namhyung@xxxxxxxxxx> wrote:
>
> As of now, bpf counters (bperf) don't support event groups.  But the
> default perf stat includes topdown metrics if supported (on recent Intel
> machines) which require groups.  That makes perf stat exiting.
>
>   $ sudo perf stat --bpf-counter true
>   bpf managed perf events do not yet support groups.
>
> Actually the test explicitly uses cycles event only, but it missed to
> pass the option when it checks the availability of the command.
>
> Fixes: 2c0cb9f56020d ("perf test: Add a shell test for 'perf stat --bpf-counters' new option")
> Cc: stable@xxxxxxxxxxxxxxx
> Cc: Song Liu <song@xxxxxxxxxx>
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>

Reviewed-by: Song Liu <song@xxxxxxxxxx>

Thanks!
Song

> ---
>  tools/perf/tests/shell/stat_bpf_counters.sh | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/tests/shell/stat_bpf_counters.sh b/tools/perf/tests/shell/stat_bpf_counters.sh
> index 513cd1e58e0e..a87bb2814b4c 100755
> --- a/tools/perf/tests/shell/stat_bpf_counters.sh
> +++ b/tools/perf/tests/shell/stat_bpf_counters.sh
> @@ -22,10 +22,10 @@ compare_number()
>  }
>
>  # skip if --bpf-counters is not supported
> -if ! perf stat --bpf-counters true > /dev/null 2>&1; then
> +if ! perf stat -e cycles --bpf-counters true > /dev/null 2>&1; then
>         if [ "$1" = "-v" ]; then
>                 echo "Skipping: --bpf-counters not supported"
> -               perf --no-pager stat --bpf-counters true || true
> +               perf --no-pager stat -e cycles --bpf-counters true || true
>         fi
>         exit 2
>  fi
> --
> 2.42.0.rc1.204.g551eb34607-goog
>