perf stat: Fix group lookup for metric group

The metric group code tries to find a group it added earlier in the
evlist. Fix the lookup to handle groups with partially overlaps
correctly. When a sub string match fails and we reset the match, we have
to compare the first element again.

I also renamed the find_evsel function to find_evsel_group to make its
purpose clearer.

With the earlier changes this fixes:

Before:

  % perf stat -M UPI,IPC sleep 1
  ...
         1,032,922      uops_retired.retire_slots #      1.1 UPI
         1,896,096      inst_retired.any
         1,896,096      inst_retired.any
         1,177,254      cpu_clk_unhalted.thread

After:

  % perf stat -M UPI,IPC sleep 1
  ...
        1,013,193      uops_retired.retire_slots #      1.1 UPI
           932,033      inst_retired.any
           932,033      inst_retired.any          #      0.9 IPC
         1,091,245      cpu_clk_unhalted.thread

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Fixes: b18f3e365019 ("perf stat: Support JSON metrics in perf stat")
Link: http://lkml.kernel.org/r/20190624193711.35241-4-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 35 insertions, 12 deletions

diff --git a/tools/perf/util/metricgroup.c b/tools/perf/util/metricgroup.c
index 90cd84e2a503..bc25995255ab 100644
--- a/tools/perf/util/metricgroup.c
+++ b/tools/perf/util/metricgroup.c
@@ -85,26 +85,49 @@ struct egroup {
         const char *metric_expr;
 };
 
-static struct perf_evsel *find_evsel(struct perf_evlist *perf_evlist,
-                                     const char **ids,
-                                     int idnum,
-                                     struct perf_evsel **metric_events)
+static bool record_evsel(int *ind, struct perf_evsel **start,
+                         int idnum,
+                         struct perf_evsel **metric_events,
+                         struct perf_evsel *ev)
+{
+        metric_events[*ind] = ev;
+        if (*ind == 0)
+                *start = ev;
+        if (++*ind == idnum) {
+                metric_events[*ind] = NULL;
+                return true;
+        }
+        return false;
+}
+
+static struct perf_evsel *find_evsel_group(struct perf_evlist *perf_evlist,
+                                           const char **ids,
+                                           int idnum,
+                                           struct perf_evsel **metric_events)
 {
         struct perf_evsel *ev, *start = NULL;
         int ind = 0;
 
         evlist__for_each_entry (perf_evlist, ev) {
+                if (ev->collect_stat)
+                        continue;
                 if (!strcmp(ev->name, ids[ind])) {
-                        metric_events[ind] = ev;
-                        if (ind == 0)
-                                start = ev;
-                        if (++ind == idnum) {
-                                metric_events[ind] = NULL;
+                        if (record_evsel(&ind, &start, idnum,
+                                         metric_events, ev))
                                 return start;
-                        }
                 } else {
+                        /*
+                         * We saw some other event that is not
+                         * in our list of events. Discard
+                         * the whole match and start again.
+                         */
                         ind = 0;
                         start = NULL;
+                        if (!strcmp(ev->name, ids[ind])) {
+                                if (record_evsel(&ind, &start, idnum,
+                                                 metric_events, ev))
+                                        return start;
+                        }
                 }
         }
         /*
@@ -134,8 +157,8 @@ static int metricgroup__setup_events(struct list_head *groups,
                         ret = -ENOMEM;
                         break;
                 }
-                evsel = find_evsel(perf_evlist, eg->ids, eg->idnum,
-                                   metric_events);
+                evsel = find_evsel_group(perf_evlist, eg->ids, eg->idnum,
+                                         metric_events);
                 if (!evsel) {
                         pr_debug("Cannot resolve %s: %s\n",
                                         eg->metric_name, eg->metric_expr);