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References: <20220422162402.147958-1-adrian.hunter@intel.com> <20220422162402.147958-6-adrian.hunter@intel.com>
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From:   Namhyung Kim <namhyung@kernel.org>
Date:   Wed, 27 Apr 2022 14:54:26 -0700
Message-ID: <CAM9d7cg8Awh9oXdCL4-GQT_R5FpgTz6DYFCfd=9g1YFQ463xSQ@mail.gmail.com>
Subject: Re: [PATCH RFC 05/21] perf auxtrace: Do not mix up mmap idx
To:     Adrian Hunter <adrian.hunter@intel.com>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@redhat.com>, Ian Rogers <irogers@google.com>,
        Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>,
        Leo Yan <leo.yan@linaro.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
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On Fri, Apr 22, 2022 at 9:24 AM Adrian Hunter <adrian.hunter@intel.com> wrote:
>
> The idx is with respect to evlist not evsel. That hasn't mattered because
> they are the same at present. Prepare for that not being the case, which it
> won't be when sideband tracking events are allowed on all CPUs even when
> auxtrace is limited to selected CPUs.
>
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> ---
>  tools/perf/util/auxtrace.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/util/auxtrace.c b/tools/perf/util/auxtrace.c
> index 10936a38031f..2d015b0be549 100644
> --- a/tools/perf/util/auxtrace.c
> +++ b/tools/perf/util/auxtrace.c
> @@ -640,8 +640,14 @@ static int evlist__enable_event_idx(struct evlist *evlist, struct evsel *evsel,
>  {
>         bool per_cpu_mmaps = !perf_cpu_map__empty(evlist->core.user_requested_cpus);
>
> -       if (per_cpu_mmaps)
> -               return perf_evsel__enable_cpu(&evsel->core, idx);
> +       if (per_cpu_mmaps) {
> +               struct perf_cpu evlist_cpu = perf_cpu_map__cpu(evlist->core.all_cpus, idx);
> +               int cpu = perf_cpu_map__idx(evsel->core.cpus, evlist_cpu);

While it can be thought of as an index from the function name,
it'd be nice if we could be explicit like cpu_map_idx.

Thanks,
Namhyung

> +
> +               if (cpu == -1)
> +                       return -EINVAL;
> +               return perf_evsel__enable_cpu(&evsel->core, cpu);
> +       }
>
>         return perf_evsel__enable_thread(&evsel->core, idx);
>  }
> --
> 2.25.1
>