Re: [PATCH] perf report: Fix --task and --stat with pipe input

From: Jiri Olsa
Date: Fri Jul 02 2021 - 06:38:25 EST


On Tue, Jun 29, 2021 at 09:30:58PM -0700, Namhyung Kim wrote:
> Current perf report fails to process a pipe input when --task
> or --stat option is used. This is because they reset all the
> tool callbacks and failed to find a matching event for a sample.
>
> When pipe input is used, the event info is passed via ATTR records
> so it needs to handle that operation. Otherwise the following error
> occurred. Note, -14 (= -EFAULT) comes from evlist__parse_sample():
>
> # perf record -a -o- sleep 1 | perf report -i- --stat
> Can't parse sample, err = -14
> 0x271044 [0x38]: failed to process type: 9
> Error:
> failed to process sample
>
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>

Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>

thanks,
jirka

> ---
> tools/perf/builtin-report.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
> index bc5c393021dc..8639bbe0969d 100644
> --- a/tools/perf/builtin-report.c
> +++ b/tools/perf/builtin-report.c
> @@ -729,9 +729,14 @@ static int count_sample_event(struct perf_tool *tool __maybe_unused,
> return 0;
> }
>
> +static int process_attr(struct perf_tool *tool __maybe_unused,
> + union perf_event *event,
> + struct evlist **pevlist);
> +
> static void stats_setup(struct report *rep)
> {
> memset(&rep->tool, 0, sizeof(rep->tool));
> + rep->tool.attr = process_attr;
> rep->tool.sample = count_sample_event;
> rep->tool.no_warn = true;
> }
> @@ -753,6 +758,7 @@ static void tasks_setup(struct report *rep)
> rep->tool.mmap = perf_event__process_mmap;
> rep->tool.mmap2 = perf_event__process_mmap2;
> }
> + rep->tool.attr = process_attr;
> rep->tool.comm = perf_event__process_comm;
> rep->tool.exit = perf_event__process_exit;
> rep->tool.fork = perf_event__process_fork;
> --
> 2.32.0.93.g670b81a890-goog
>