Re: [PATCH 2/2] perf parse-event: Fix cpu map leaks

[Namhyung Kim]

On Wed, Sep 16, 2020 at 11:00 PM Arnaldo Carvalho de Melo
<acme@xxxxxxxxxx> wrote:
>
> Em Wed, Sep 16, 2020 at 02:31:31PM +0900, Namhyung Kim escreveu:
> > Like evlist cpu map, evsel's cpu map should have a proper refcount.
> > As it's created with a refcount, we don't need to get an extra count.
> > Thanks to Arnaldo for the simpler suggestion.
>
> You forgot this part:
>
>
> [acme@five perf]$ git diff
> diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> index 667cbca1547ac5f6..0154331ea213f166 100644
> --- a/tools/perf/util/parse-events.c
> +++ b/tools/perf/util/parse-events.c
> @@ -353,7 +353,7 @@ __add_event(struct list_head *list, int *idx,
>             const char *cpu_list)
>  {
>         struct evsel *evsel;
> -       struct perf_cpu_map *cpus = pmu ? pmu->cpus :
> +       struct perf_cpu_map *cpus = pmu ? perf_cpu_map__get(pmu->cpus) :
>                                cpu_list ? perf_cpu_map__new(cpu_list) : NULL;
>
>         if (init_attr)
>
> Right?

Oops, you're right!  Will send v2 soon.

Thanks
Namhyung


> > This fixes the following ASAN report:
> >
> >   Direct leak of 840 byte(s) in 70 object(s) allocated from:
> >     #0 0x7fe36703f628 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x107628)
> >     #1 0x559fbbf611ca in cpu_map__trim_new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:79
> >     #2 0x559fbbf6229c in perf_cpu_map__new /home/namhyung/project/linux/tools/lib/perf/cpumap.c:237
> >     #3 0x559fbbcc6c6d in __add_event util/parse-events.c:357
> >     #4 0x559fbbcc6c6d in add_event_tool util/parse-events.c:408
> >     #5 0x559fbbcc6c6d in parse_events_add_tool util/parse-events.c:1414
> >     #6 0x559fbbd8474d in parse_events_parse util/parse-events.y:439
> >     #7 0x559fbbcc95da in parse_events__scanner util/parse-events.c:2096
> >     #8 0x559fbbcc95da in __parse_events util/parse-events.c:2141
> >     #9 0x559fbbc2788b in check_parse_id tests/pmu-events.c:406
> >     #10 0x559fbbc2788b in check_parse_id tests/pmu-events.c:393
> >     #11 0x559fbbc2788b in check_parse_fake tests/pmu-events.c:436
> >     #12 0x559fbbc2788b in metric_parse_fake tests/pmu-events.c:553
> >     #13 0x559fbbc27e2d in test_parsing_fake tests/pmu-events.c:599
> >     #14 0x559fbbc27e2d in test_parsing_fake tests/pmu-events.c:574
> >     #15 0x559fbbc0109b in run_test tests/builtin-test.c:410
> >     #16 0x559fbbc0109b in test_and_print tests/builtin-test.c:440
> >     #17 0x559fbbc03e69 in __cmd_test tests/builtin-test.c:695
> >     #18 0x559fbbc03e69 in cmd_test tests/builtin-test.c:807
> >     #19 0x559fbbc691f4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:312
> >     #20 0x559fbbb071a8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:364
> >     #21 0x559fbbb071a8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:408
> >     #22 0x559fbbb071a8 in main /home/namhyung/project/linux/tools/perf/perf.c:538
> >     #23 0x7fe366b68cc9 in __libc_start_main ../csu/libc-start.c:308
> >
> > And I've failed which commit introduced this bug as the code was
> > heavily changed since then. ;-/
> >
> > Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
> > Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> > ---
> >  tools/perf/util/parse-events.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
> > index 176a51698a64..204395596381 100644
> > --- a/tools/perf/util/parse-events.c
> > +++ b/tools/perf/util/parse-events.c
> > @@ -366,7 +366,7 @@ __add_event(struct list_head *list, int *idx,
> >       }
> >
> >       (*idx)++;
> > -     evsel->core.cpus   = perf_cpu_map__get(cpus);
> > +     evsel->core.cpus = cpus;
> >       evsel->core.own_cpus = perf_cpu_map__get(cpus);
> >       evsel->core.system_wide = pmu ? pmu->is_uncore : false;
> >       evsel->auto_merge_stats = auto_merge_stats;
> > --
> > 2.28.0.618.gf4bc123cb7-goog
> >
>
> --
>
> - Arnaldo