Re: [PATCH] perf stat: Fix duration_time value for higher intervals

From: Arnaldo Carvalho de Melo
Date: Mon May 18 2020 - 11:23:57 EST


Em Mon, May 18, 2020 at 03:14:45PM +0200, Jiri Olsa escreveu:
> Joakim reported wrong duration_time value for interval bigger
> than 4000 [1].
>
> The problem is in the interval value we pass to update_stats
> function, which is typed as 'unsigned int' and overflows when
> we get over 2^32 (happens between intervals 4000 and 5000).
>
> Retyping the passed value to unsigned long long.

Thanks, applied and added this:

Fixes: b90f1333ef08 ("perf stat: Update walltime_nsecs_stats in interval mode")

Ok?

- Arnaldo

> [1] https://www.spinics.net/lists/linux-perf-users/msg11777.html
>
> Reported-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> ---
> tools/perf/builtin-stat.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
> index e0c1ad23c768..4deb2d46a343 100644
> --- a/tools/perf/builtin-stat.c
> +++ b/tools/perf/builtin-stat.c
> @@ -367,7 +367,7 @@ static void process_interval(void)
> }
>
> init_stats(&walltime_nsecs_stats);
> - update_stats(&walltime_nsecs_stats, stat_config.interval * 1000000);
> + update_stats(&walltime_nsecs_stats, stat_config.interval * 1000000ULL);
> print_counters(&rs, 0, NULL);
> }
>
> --
> 2.25.4
>

--

- Arnaldo