Re: [PATCH 1/2] perf tools: Don't sort the task scan result from /proc

From: Ian Rogers
Date: Fri Jul 01 2022 - 19:06:23 EST


On Fri, Jul 1, 2022 at 1:55 PM Namhyung Kim <namhyung@xxxxxxxxxx> wrote:
>
> It should not sort the result as procfs already returns a proper
> ordering of tasks. Actually sorting the order caused problems that it
> doesn't guararantee to process the main thread first.
>
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>

Acked-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks,
Ian

> ---
> tools/perf/util/synthetic-events.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c
> index 27acdc5e5723..a068f42833c3 100644
> --- a/tools/perf/util/synthetic-events.c
> +++ b/tools/perf/util/synthetic-events.c
> @@ -754,7 +754,7 @@ static int __event__synthesize_thread(union perf_event *comm_event,
> snprintf(filename, sizeof(filename), "%s/proc/%d/task",
> machine->root_dir, pid);
>
> - n = scandir(filename, &dirent, filter_task, alphasort);
> + n = scandir(filename, &dirent, filter_task, NULL);
> if (n < 0)
> return n;
>
> @@ -987,7 +987,7 @@ int perf_event__synthesize_threads(struct perf_tool *tool,
> return 0;
>
> snprintf(proc_path, sizeof(proc_path), "%s/proc", machine->root_dir);
> - n = scandir(proc_path, &dirent, filter_task, alphasort);
> + n = scandir(proc_path, &dirent, filter_task, NULL);
> if (n < 0)
> return err;
>
> --
> 2.37.0.rc0.161.g10f37bed90-goog
>