Re: [PATCH V2 4/8] perf metrics: Sort the Default metricgroup

[Ian Rogers]

On Wed, Jun 14, 2023 at 9:30 PM Ian Rogers <irogers@xxxxxxxxxx> wrote:
>
> On Wed, Jun 14, 2023 at 5:18 PM <kan.liang@xxxxxxxxxxxxxxx> wrote:
> >
> > From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
> >
> > The new default mode will print the metrics as a metric group. The
> > metrics from the same metric group must be adjacent to each other in the
> > metric list. But the metric_list_cmp() sorts metrics by the number of
> > events.
> >
> > Add a new sort for the Default metricgroup, which sorts by
> > default_metricgroup_name and metric_name.
> >
> > Add is_default in the struct metric_event to indicate that it's from
> > the Default metricgroup.
> >
> > Store the displayed metricgroup name of the Default metricgroup into
> > the metric expr for output.
> >
> > Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
> > ---
> >  tools/perf/util/metricgroup.c | 35 +++++++++++++++++++++++++++++++++++
> >  tools/perf/util/metricgroup.h |  3 +++
> >  2 files changed, 38 insertions(+)
> >
> > diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
> > index 8b19644ade7d..acf86b15ee49 100644
> > --- a/tools/perf/util/metricgroup.c
> > +++ b/tools/perf/util/metricgroup.c
> > @@ -79,6 +79,7 @@ static struct rb_node *metric_event_new(struct rblist *rblist __maybe_unused,
> >                 return NULL;
> >         memcpy(me, entry, sizeof(struct metric_event));
> >         me->evsel = ((struct metric_event *)entry)->evsel;
> > +       me->is_default = false;
> >         INIT_LIST_HEAD(&me->head);
> >         return &me->nd;
> >  }
> > @@ -1160,6 +1161,25 @@ static int metric_list_cmp(void *priv __maybe_unused, const struct list_head *l,
> >         return right_count - left_count;
> >  }
> >
> > +/**
> > + * default_metricgroup_cmp - Implements complex key for the Default metricgroup
> > + *                          that first sorts by default_metricgroup_name, then
> > + *                          metric_name.
> > + */
> > +static int default_metricgroup_cmp(void *priv __maybe_unused,
> > +                                  const struct list_head *l,
> > +                                  const struct list_head *r)
> > +{
> > +       const struct metric *left = container_of(l, struct metric, nd);
> > +       const struct metric *right = container_of(r, struct metric, nd);
> > +       int diff = strcmp(right->default_metricgroup_name, left->default_metricgroup_name);
> > +
> > +       if (diff)
> > +               return diff;
> > +
> > +       return strcmp(right->metric_name, left->metric_name);
> > +}
> > +
> >  struct metricgroup__add_metric_data {
> >         struct list_head *list;
> >         const char *pmu;
> > @@ -1515,6 +1535,7 @@ static int parse_groups(struct evlist *perf_evlist,
> >         LIST_HEAD(metric_list);
> >         struct metric *m;
> >         bool tool_events[PERF_TOOL_MAX] = {false};
> > +       bool is_default = !strcmp(str, "Default");
> >         int ret;
> >
> >         if (metric_events_list->nr_entries == 0)
> > @@ -1549,6 +1570,9 @@ static int parse_groups(struct evlist *perf_evlist,
> >                         goto out;
> >         }
> >
> > +       if (is_default)
> > +               list_sort(NULL, &metric_list, default_metricgroup_cmp);
> > +
> >         list_for_each_entry(m, &metric_list, nd) {
> >                 struct metric_event *me;
> >                 struct evsel **metric_events;
> > @@ -1637,6 +1661,17 @@ static int parse_groups(struct evlist *perf_evlist,
> >                 expr->metric_unit = m->metric_unit;
> >                 expr->metric_events = metric_events;
> >                 expr->runtime = m->pctx->sctx.runtime;
> > +               if (m->pmu && strcmp(m->pmu, "cpu")) {
> > +                       char *name;
> > +
> > +                       if (asprintf(&name, "%s (%s)", m->default_metricgroup_name, m->pmu) < 0)
>
> With EXTRA_CFLAGS="-fsanitize=address" this is causing:
>
> $ perf test 7 -vv -F
>   7: PMU events                                                      :
> ...
>   7.5: Parsing of metric thresholds with fake PMUs                   :
> ...
> ==2072355==ERROR: LeakSanitizer: detected memory leaks
>
> Direct leak of 6199 byte(s) in 340 object(s) allocated from:
>    #0 0x7f24cce7077b in __interceptor_strdup
> ../../../../src/libsanitizer/asan/asan_interceptors.cp
> p:439
>    #1 0x55972b328abd in asprintf util/util.c:566
>    #2 0x55972b251dbd in parse_groups util/metricgroup.c:1667
>    #3 0x55972b25231f in metricgroup__parse_groups_test util/metricgroup.c:1719
>    #4 0x55972b139aff in test__parsing_callback tests/pmu-events.c:837
>    #5 0x55972b5119a9 in pmu_metrics_table_for_each_metric
> /tmp/perf/pmu-events/pmu-events.c:61641
>    #6 0x55972b511fdf in pmu_for_each_core_metric
> /tmp/perf/pmu-events/pmu-events.c:61742
>    #7 0x55972b13a3bc in test__parsing tests/pmu-events.c:898
>    #8 0x55972b106cd7 in run_test tests/builtin-test.c:236
>    #9 0x55972b106f7c in test_and_print tests/builtin-test.c:265
>    #10 0x55972b107f96 in __cmd_test tests/builtin-test.c:436
>    #11 0x55972b10927a in cmd_test tests/builtin-test.c:559
>    #12 0x55972b19584a in run_builtin
> /home/irogers/kernel.org/tools/perf/perf.c:323
>    #13 0x55972b195dbb in handle_internal_command
> /home/irogers/kernel.org/tools/perf/perf.c:377
>    #14 0x55972b196183 in run_argv /home/irogers/kernel.org/tools/perf/perf.c:421
>    #15 0x55972b1966eb in main /home/irogers/kernel.org/tools/perf/perf.c:537
>    #16 0x7f24cbe46189 in __libc_start_call_main
> ../sysdeps/nptl/libc_start_call_main.h:58
>
> SUMMARY: AddressSanitizer: 6199 byte(s) leaked in 340 allocation(s)
>
> As this is mixing allocated and unallocated strings, you like want to
> strdup the unallocated ones, then add a free to the exit routine.
>
> Thanks,
> Ian

Except for the memory leak, everything looks good here. Will ack with
the memory leak fix.

Thanks,
Ian

> > +                               expr->default_metricgroup_name = m->default_metricgroup_name;
> > +                       else
> > +                               expr->default_metricgroup_name = name;
> > +               } else
> > +                       expr->default_metricgroup_name = m->default_metricgroup_name;
> > +               if (is_default)
> > +                       me->is_default = true;
> >                 list_add(&expr->nd, &me->head);
> >         }
> >
> > diff --git a/tools/perf/util/metricgroup.h b/tools/perf/util/metricgroup.h
> > index bf18274c15df..d5325c6ec8e1 100644
> > --- a/tools/perf/util/metricgroup.h
> > +++ b/tools/perf/util/metricgroup.h
> > @@ -22,6 +22,7 @@ struct cgroup;
> >  struct metric_event {
> >         struct rb_node nd;
> >         struct evsel *evsel;
> > +       bool is_default; /* the metric evsel from the Default metricgroup */
> >         struct list_head head; /* list of metric_expr */
> >  };
> >
> > @@ -55,6 +56,8 @@ struct metric_expr {
> >          * more human intelligible) and then add "MiB" afterward when displayed.
> >          */
> >         const char *metric_unit;
> > +       /** Displayed metricgroup name of the Default metricgroup */
> > +       const char *default_metricgroup_name;
> >         /** Null terminated array of events used by the metric. */
> >         struct evsel **metric_events;
> >         /** Null terminated array of referenced metrics. */
> > --
> > 2.35.1
> >