Re: [PATCH] perf metrics: Ensure at least 1 id per metric

From: Arnaldo Carvalho de Melo
Date: Sun Jun 19 2022 - 10:24:52 EST


Em Fri, Jun 17, 2022 at 06:39:57PM -0700, Ian Rogers escreveu:
> We may have no events for a metric evaluated to a constant. In such a
> case ensure a tool event is at least evaluated for metric parsing and
> displaying.

Thanks, applied.

- Arnaldo


> Fixes: 8586d2744ff3 ("perf metrics: Don't add all tool events for sharing")
> Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> ---
> tools/perf/util/metricgroup.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
> index ee8fcfa115e5..8f7baeabc5cf 100644
> --- a/tools/perf/util/metricgroup.c
> +++ b/tools/perf/util/metricgroup.c
> @@ -1372,6 +1372,7 @@ static int parse_ids(bool metric_no_merge, struct perf_pmu *fake_pmu,
>
> *out_evlist = NULL;
> if (!metric_no_merge || hashmap__size(ids->ids) == 0) {
> + bool added_event = false;
> int i;
> /*
> * We may fail to share events between metrics because a tool
> @@ -1393,8 +1394,16 @@ static int parse_ids(bool metric_no_merge, struct perf_pmu *fake_pmu,
> if (!tmp)
> return -ENOMEM;
> ids__insert(ids->ids, tmp);
> + added_event = true;
> }
> }
> + if (!added_event && hashmap__size(ids->ids) == 0) {
> + char *tmp = strdup("duration_time");
> +
> + if (!tmp)
> + return -ENOMEM;
> + ids__insert(ids->ids, tmp);
> + }
> }
> ret = metricgroup__build_event_string(&events, ids, modifier,
> has_constraint);
> --
> 2.37.0.rc0.104.g0611611a94-goog

--

- Arnaldo