Re: [PATCH V13 11/14] perf tools: Add missing_features for aux_start_paused, aux_pause, aux_resume

[Leo Yan <leo.yan@xxxxxxx>]

On 10/14/24 11:51, Adrian Hunter wrote:
> Display "feature is not supported" error message if aux_start_paused,
> aux_pause or aux_resume result in a perf_event_open() error.
>
> Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> Acked-by: Ian Rogers <irogers@xxxxxxxxxx>
> Reviewed-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>

Reviewed-by: Leo Yan <leo.yan@xxxxxxx>

> ---
>
>
> Changes in V13:
>          Add error message also in EOPNOTSUPP case (Leo)
>
>
>   tools/perf/util/evsel.c | 12 ++++++++++++
>   tools/perf/util/evsel.h |  1 +
>   2 files changed, 13 insertions(+)
>
> diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> index 9621c8c12406..fd28ff5437b5 100644
> --- a/tools/perf/util/evsel.c
> +++ b/tools/perf/util/evsel.c
> @@ -2177,6 +2177,12 @@ bool evsel__detect_missing_features(struct evsel *evsel)
>                  perf_missing_features.inherit_sample_read = true;
>                  pr_debug2("Using PERF_SAMPLE_READ / :S modifier is not compatible with inherit, falling back to no-inherit.\n");
>                  return true;
> +       } else if (!perf_missing_features.aux_pause_resume &&
> +           (evsel->core.attr.aux_pause || evsel->core.attr.aux_resume ||
> +            evsel->core.attr.aux_start_paused)) {
> +               perf_missing_features.aux_pause_resume = true;
> +               pr_debug2_peo("Kernel has no aux_pause/aux_resume support, bailing out\n");
> +               return false;
>          } else if (!perf_missing_features.branch_counters &&
>              (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS)) {
>                  perf_missing_features.branch_counters = true;
> @@ -3397,6 +3403,10 @@ int evsel__open_strerror(struct evsel *evsel, struct target *target,
>                          return scnprintf(msg, size,
>          "%s: PMU Hardware doesn't support 'aux_output' feature",
>                                           evsel__name(evsel));
> +               if (evsel->core.attr.aux_action)
> +                       return scnprintf(msg, size,
> +       "%s: PMU Hardware doesn't support 'aux_action' feature",
> +                                       evsel__name(evsel));
>                  if (evsel->core.attr.sample_period != 0)
>                          return scnprintf(msg, size,
>          "%s: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat'",
> @@ -3427,6 +3437,8 @@ int evsel__open_strerror(struct evsel *evsel, struct target *target,
>                          return scnprintf(msg, size, "clockid feature not supported.");
>                  if (perf_missing_features.clockid_wrong)
>                          return scnprintf(msg, size, "wrong clockid (%d).", clockid);
> +               if (perf_missing_features.aux_pause_resume)
> +                       return scnprintf(msg, size, "The 'aux_pause / aux_resume' feature is not supported, update the kernel.");
>                  if (perf_missing_features.aux_output)
>                          return scnprintf(msg, size, "The 'aux_output' feature is not supported, update the kernel.");
>                  if (!target__has_cpu(target))
> diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
> index bd08d94d3f8a..d40df2051718 100644
> --- a/tools/perf/util/evsel.h
> +++ b/tools/perf/util/evsel.h
> @@ -221,6 +221,7 @@ struct perf_missing_features {
>          bool weight_struct;
>          bool read_lost;
>          bool branch_counters;
> +       bool aux_pause_resume;
>          bool inherit_sample_read;
>   };
>
> --
> 2.43.0