Re: [PATCH v4 1/3] perf stat: introduce stats for the user and system rusage times

[Ian Rogers]

On Wed, Apr 20, 2022 at 3:24 AM Florian Fischer
<florian.fischer@muhq.space> wrote:
>
> This is preparation for exporting rusage values as tool events.
>
> Add new global stats tracking the values obtained via rusage.
> For now only ru_utime and ru_stime are part of the tracked stats.
> Both are stored as nanoseconds to be consistent with 'duration_time',
> although the finest resolution the struct timeval data in rusage
> provides are microseconds.
>
> Signed-off-by: Florian Fischer <florian.fischer@muhq.space>
> ---
>  tools/perf/builtin-stat.c     |  5 ++++-
>  tools/perf/util/stat-shadow.c |  2 ++
>  tools/perf/util/stat.h        | 21 +++++++++++++++++++++
>  3 files changed, 27 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
> index a96f106dc93a..61faffb535f5 100644
> --- a/tools/perf/builtin-stat.c
> +++ b/tools/perf/builtin-stat.c
> @@ -216,6 +216,7 @@ static struct perf_stat_config stat_config = {
>         .run_count              = 1,
>         .metric_only_len        = METRIC_ONLY_LEN,
>         .walltime_nsecs_stats   = &walltime_nsecs_stats,
> +       .ru_stats               = &ru_stats,
>         .big_num                = true,
>         .ctl_fd                 = -1,
>         .ctl_fd_ack             = -1,
> @@ -1010,8 +1011,10 @@ static int __run_perf_stat(int argc, const char **argv, int run_idx)
>                 evlist__reset_prev_raw_counts(evsel_list);
>                 runtime_stat_reset(&stat_config);
>                 perf_stat__reset_shadow_per_stat(&rt_stat);
> -       } else
> +       } else {
>                 update_stats(&walltime_nsecs_stats, t1 - t0);
> +               update_rusage_stats(&ru_stats, &stat_config.ru_data);
> +       }
>
>         /*
>          * Closing a group leader splits the group, and as we only disable
> diff --git a/tools/perf/util/stat-shadow.c b/tools/perf/util/stat-shadow.c
> index 10af7804e482..ea4c35e4f1da 100644
> --- a/tools/perf/util/stat-shadow.c
> +++ b/tools/perf/util/stat-shadow.c
> @@ -26,6 +26,7 @@
>
>  struct runtime_stat rt_stat;
>  struct stats walltime_nsecs_stats;
> +struct rusage_stats ru_stats;
>
>  struct saved_value {
>         struct rb_node rb_node;
> @@ -199,6 +200,7 @@ void perf_stat__reset_shadow_stats(void)
>  {
>         reset_stat(&rt_stat);
>         memset(&walltime_nsecs_stats, 0, sizeof(walltime_nsecs_stats));
> +       memset(&ru_stats, 0, sizeof(ru_stats));
>  }
>
>  void perf_stat__reset_shadow_per_stat(struct runtime_stat *st)
> diff --git a/tools/perf/util/stat.h b/tools/perf/util/stat.h
> index 335d19cc3063..e31c94d952e9 100644
> --- a/tools/perf/util/stat.h
> +++ b/tools/perf/util/stat.h
> @@ -108,6 +108,11 @@ struct runtime_stat {
>         struct rblist value_list;
>  };
>
> +struct rusage_stats {
> +       struct stats ru_utime_usec_stat;
> +       struct stats ru_stime_usec_stat;
> +};
> +
>  typedef struct aggr_cpu_id (*aggr_get_id_t)(struct perf_stat_config *config, struct perf_cpu cpu);
>
>  struct perf_stat_config {
> @@ -148,6 +153,7 @@ struct perf_stat_config {
>         const char              *csv_sep;
>         struct stats            *walltime_nsecs_stats;
>         struct rusage            ru_data;
> +       struct rusage_stats              *ru_stats;
>         struct cpu_aggr_map     *aggr_map;
>         aggr_get_id_t            aggr_get_id;
>         struct cpu_aggr_map     *cpus_aggr_map;
> @@ -177,6 +183,20 @@ static inline void init_stats(struct stats *stats)
>         stats->max  = 0;
>  }
>
> +static inline void init_rusage_stats(struct rusage_stats *ru_stats) {
> +       init_stats(&ru_stats->ru_utime_usec_stat);
> +       init_stats(&ru_stats->ru_stime_usec_stat);
> +}

Is there a missing call to this function?

Thanks,
Ian

> +static inline void update_rusage_stats(struct rusage_stats *ru_stats, struct rusage* rusage) {
> +       const u64 us_to_ns = 1000;
> +       const u64 s_to_ns = 1000000000;
> +       update_stats(&ru_stats->ru_utime_usec_stat,
> +                    (rusage->ru_utime.tv_usec * us_to_ns + rusage->ru_utime.tv_sec * s_to_ns));
> +       update_stats(&ru_stats->ru_stime_usec_stat,
> +                    (rusage->ru_stime.tv_usec * us_to_ns + rusage->ru_stime.tv_sec * s_to_ns));
> +}
> +
>  struct evsel;
>  struct evlist;
>
> @@ -196,6 +216,7 @@ bool __perf_stat_evsel__is(struct evsel *evsel, enum perf_stat_evsel_id id);
>
>  extern struct runtime_stat rt_stat;
>  extern struct stats walltime_nsecs_stats;
> +extern struct rusage_stats ru_stats;
>
>  typedef void (*print_metric_t)(struct perf_stat_config *config,
>                                void *ctx, const char *color, const char *unit,
> --
> 2.36.0
>