Re: [PATCH] perf evlist: Ensure grouped events with same cpu map

[Jin, Yao]

Hi Jiri,

On 5/22/2020 5:53 PM, Jiri Olsa wrote:

On Thu, May 21, 2020 at 02:22:40PM +0800, Jin Yao wrote:

SNIP

---
  tools/perf/builtin-stat.c |  3 +++
  tools/perf/util/evlist.c  | 32 ++++++++++++++++++++++++++++++++
  tools/perf/util/evlist.h  |  5 +++++
  3 files changed, 40 insertions(+)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 377e575f9645..0e4fc6b3323c 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -584,6 +584,9 @@ static int __run_perf_stat(int argc, const char **argv, int 
run_idx)
        if (affinity__setup(&affinity) < 0)
                return -1;

+ if (!evlist__cpus_matched(evsel_list))

+               evlist__force_disable_group(evsel_list);
+
        evlist__for_each_cpu (evsel_list, i, cpu) {
                affinity__set(&affinity, cpu);

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c

index 2a9de6491700..fc6e410ca63b 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -1704,3 +1704,35 @@ struct evsel *perf_evlist__reset_weak_group(struct 
evlist *evsel_list,
        }
        return leader;
  }
+
+bool evlist__cpus_matched(struct evlist *evlist)
+{
+       struct evsel *prev = evlist__first(evlist), *evsel = prev;
+
+       if (prev->core.nr_members <= 1)
+               return true;

hum, this assumes there's only one group in evlist?

how about case like A,{B,C},D,{E,F}

Yes, you are right, I need to consider the case such as A,{B,C},D,{E,F}. I will 
post v2.

also please add automated tests for this

I will add case for testing the group members.

+
+       evlist__for_each_entry_continue(evlist, evsel) {
+               if (evsel->core.cpus->nr != prev->core.cpus->nr)
+                       return false;
+
+               for (int i = 0; i < evsel->core.cpus->nr; i++) {
+                       if (evsel->core.cpus->map[i] != prev->core.cpus->map[i])
+                               return false;
+               }
+
+               prev = evsel;
+       }
+
+       return true;
+}
+
+void evlist__force_disable_group(struct evlist *evlist)
+{
+       struct evsel *evsel;

we need to put some warning for user in here

Yes, agree. I will add warning in v2.

Thanks
Jin Yao

thanks,
jirka

+
+       evlist__for_each_entry(evlist, evsel) {
+               evsel->leader = evsel;
+               evsel->core.nr_members = 0;
+       }
+}
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index b6f325dfb4d2..ea7a53166cbd 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -355,4 +355,9 @@ void perf_evlist__force_leader(struct evlist *evlist);
  struct evsel *perf_evlist__reset_weak_group(struct evlist *evlist,
                                                 struct evsel *evsel,
                                                bool close);
+
+bool evlist__cpus_matched(struct evlist *evlist);
+
+void evlist__force_disable_group(struct evlist *evlist);
+
  #endif /* __PERF_EVLIST_H */
--
2.17.1