Messages in this thread | | | From | Ian Rogers <> | Date | Tue, 2 Jun 2020 08:48:04 -0700 | Subject | Re: [PATCHv3] perf stat: Ensure group is defined on top of the same cpu mask |
| |
On Tue, Jun 2, 2020 at 3:17 AM Jiri Olsa <jolsa@redhat.com> wrote: > > Jin Yao reported the issue (and posted first versions of this change) > with groups being defined over events with different cpu mask. > > This causes assert aborts in get_group_fd, like: > > # perf stat -M "C2_Pkg_Residency" -a -- sleep 1 > perf: util/evsel.c:1464: get_group_fd: Assertion `!(fd == -1)' failed. > Aborted > > All the events in the group have to be defined over the same > cpus so the group_fd can be found for every leader/member pair. > > Adding check to ensure this condition is met and removing the > group (with warning) if we detect mixed cpus, like: > > $ sudo perf stat -e '{power/energy-cores/,cycles},{instructions,power/energy-cores/}' > WARNING: event cpu maps do not match, disabling group: > anon group { power/energy-cores/, cycles } > anon group { instructions, power/energy-cores/ } > > Ian asked also for cpu maps details, it's displayed in verbose mode: > > $ sudo perf stat -e '{cycles,power/energy-cores/}' -v > WARNING: group events cpu maps do not match, disabling group: > anon group { power/energy-cores/, cycles } > power/energy-cores/: 0 > cycles: 0-7 > anon group { instructions, power/energy-cores/ } > instructions: 0-7 > power/energy-cores/: 0 > > Fixes: 6a4bb04caacc8 ("perf tools: Enable grouping logic for parsed events") > Co-developed-by: Jin Yao <yao.jin@linux.intel.com> > Signed-off-by: Jin Yao <yao.jin@linux.intel.com> > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Thanks! Ian
> --- > tools/perf/builtin-stat.c | 55 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 55 insertions(+) > > v3 changes: > - reword the warning with Ian's suggestion > > diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c > index b2b79aa161dd..9be020e0098a 100644 > --- a/tools/perf/builtin-stat.c > +++ b/tools/perf/builtin-stat.c > @@ -190,6 +190,59 @@ static struct perf_stat_config stat_config = { > .big_num = true, > }; > > +static bool cpus_map_matched(struct evsel *a, struct evsel *b) > +{ > + if (!a->core.cpus && !b->core.cpus) > + return true; > + > + if (!a->core.cpus || !b->core.cpus) > + return false; > + > + if (a->core.cpus->nr != b->core.cpus->nr) > + return false; > + > + for (int i = 0; i < a->core.cpus->nr; i++) { > + if (a->core.cpus->map[i] != b->core.cpus->map[i]) > + return false; > + } > + > + return true; > +} > + > +static void evlist__check_cpu_maps(struct evlist *evlist) > +{ > + struct evsel *evsel, *pos, *leader; > + char buf[1024]; > + > + evlist__for_each_entry(evlist, evsel) { > + leader = evsel->leader; > + > + /* Check that leader matches cpus with each member. */ > + if (leader == evsel) > + continue; > + if (cpus_map_matched(leader, evsel)) > + continue; > + > + /* If there's mismatch disable the group and warn user. */ > + WARN_ONCE(1, "WARNING: grouped events cpus do not match, disabling group:\n"); > + evsel__group_desc(leader, buf, sizeof(buf)); > + pr_warning(" %s\n", buf); > + > + if (verbose) { > + cpu_map__snprint(leader->core.cpus, buf, sizeof(buf)); > + pr_warning(" %s: %s\n", leader->name, buf); > + cpu_map__snprint(evsel->core.cpus, buf, sizeof(buf)); > + pr_warning(" %s: %s\n", evsel->name, buf); > + } > + > + for_each_group_evsel(pos, leader) { > + pos->leader = pos; > + pos->core.nr_members = 0; > + } > + evsel->leader->core.nr_members = 0; > + } > +} > + > static inline void diff_timespec(struct timespec *r, struct timespec *a, > struct timespec *b) > { > @@ -2113,6 +2166,8 @@ int cmd_stat(int argc, const char **argv) > goto out; > } > > + evlist__check_cpu_maps(evsel_list); > + > /* > * Initialize thread_map with comm names, > * so we could print it out on output. > -- > 2.25.4 >
| |