Re: [PATCH 07/19] perf stat: Add struct perf_stat_aggr to perf_stat_evsel

[Namhyung Kim <namhyung@kernel.org>]

On Mon, Oct 10, 2022 at 4:01 PM Ian Rogers <irogers@google.com> wrote:
>
> On Sun, Oct 9, 2022 at 10:36 PM Namhyung Kim <namhyung@kernel.org> wrote:
> >
> > The perf_stat_aggr struct is to keep aggregated counter values and the
> > states according to the aggregation mode.  The number of entries is
> > depends on the mode and this is a preparation for the later use.
> >
> > Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> > ---
> >  tools/perf/util/stat.c | 34 +++++++++++++++++++++++++++-------
> >  tools/perf/util/stat.h |  9 +++++++++
> >  2 files changed, 36 insertions(+), 7 deletions(-)
> >
> > diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
> > index 8ec8bb4a9912..c9d5aa295b54 100644
> > --- a/tools/perf/util/stat.c
> > +++ b/tools/perf/util/stat.c
> > @@ -133,15 +133,33 @@ static void perf_stat_evsel_id_init(struct evsel *evsel)
> >  static void evsel__reset_stat_priv(struct evsel *evsel)
> >  {
> >         struct perf_stat_evsel *ps = evsel->stats;
> > +       struct perf_stat_aggr *aggr = ps->aggr;
> >
> >         init_stats(&ps->res_stats);
> > +
> > +       if (aggr)
> > +               memset(aggr, 0, sizeof(*aggr) * ps->nr_aggr);
> >  }
> >
> > -static int evsel__alloc_stat_priv(struct evsel *evsel)
> > +
> > +static int evsel__alloc_stat_priv(struct evsel *evsel, int nr_aggr)
> >  {
> > -       evsel->stats = zalloc(sizeof(struct perf_stat_evsel));
> > -       if (evsel->stats == NULL)
> > +       struct perf_stat_evsel *ps;
> > +
> > +       ps = zalloc(sizeof(*ps));
> > +       if (ps == NULL)
> >                 return -ENOMEM;
> > +
> > +       if (nr_aggr) {
> > +               ps->nr_aggr = nr_aggr;
> > +               ps->aggr = calloc(nr_aggr, sizeof(*ps->aggr));
> > +               if (ps->aggr == NULL) {
> > +                       free(ps);
> > +                       return -ENOMEM;
> > +               }
> > +       }
> > +
> > +       evsel->stats = ps;
> >         perf_stat_evsel_id_init(evsel);
> >         evsel__reset_stat_priv(evsel);
> >         return 0;
> > @@ -151,8 +169,10 @@ static void evsel__free_stat_priv(struct evsel *evsel)
> >  {
> >         struct perf_stat_evsel *ps = evsel->stats;
> >
> > -       if (ps)
> > +       if (ps) {
> > +               zfree(&ps->aggr);
> >                 zfree(&ps->group_data);
> > +       }
> >         zfree(&evsel->stats);
> >  }
> >
> > @@ -181,9 +201,9 @@ static void evsel__reset_prev_raw_counts(struct evsel *evsel)
> >                 perf_counts__reset(evsel->prev_raw_counts);
> >  }
> >
> > -static int evsel__alloc_stats(struct evsel *evsel, bool alloc_raw)
> > +static int evsel__alloc_stats(struct evsel *evsel, int nr_aggr, bool alloc_raw)
> >  {
> > -       if (evsel__alloc_stat_priv(evsel) < 0 ||
> > +       if (evsel__alloc_stat_priv(evsel, nr_aggr) < 0 ||
> >             evsel__alloc_counts(evsel) < 0 ||
> >             (alloc_raw && evsel__alloc_prev_raw_counts(evsel) < 0))
> >                 return -ENOMEM;
> > @@ -196,7 +216,7 @@ int evlist__alloc_stats(struct evlist *evlist, bool alloc_raw)
> >         struct evsel *evsel;
> >
> >         evlist__for_each_entry(evlist, evsel) {
> > -               if (evsel__alloc_stats(evsel, alloc_raw))
> > +               if (evsel__alloc_stats(evsel, 0, alloc_raw))
> >                         goto out_free;
> >         }
> >
> > diff --git a/tools/perf/util/stat.h b/tools/perf/util/stat.h
> > index b0899c6e002f..ea356e5aa351 100644
> > --- a/tools/perf/util/stat.h
> > +++ b/tools/perf/util/stat.h
> > @@ -8,6 +8,7 @@
> >  #include <sys/resource.h>
> >  #include "cpumap.h"
> >  #include "rblist.h"
> > +#include "counts.h"
> >
> >  struct perf_cpu_map;
> >  struct perf_stat_config;
> > @@ -42,9 +43,17 @@ enum perf_stat_evsel_id {
> >         PERF_STAT_EVSEL_ID__MAX,
> >  };
> >
>
> The new struct variables below are all worth comments.

Sure, will add.

>
> > +struct perf_stat_aggr {
> > +       struct perf_counts_values       counts;
> > +       int                             nr;
>
> Could this value be derived from counts.values.size ?

Do you mean sizeof() or ARRAY_SIZE() for counts.values?
There's no counts.values.size..

It's a completely different thing.  It's to count how many CPUs are
aggregated to the entry (aggregate-number in JSON).

Thanks,
Namhyung


>
> > +       bool                            failed;
> > +};
> > +
> >  struct perf_stat_evsel {
> >         struct stats             res_stats;
> >         enum perf_stat_evsel_id  id;
> > +       int                      nr_aggr;
> > +       struct perf_stat_aggr   *aggr;
> >         u64                     *group_data;
> >  };
> >
> > --
> > 2.38.0.rc1.362.ged0d419d3c-goog
> >