perf tools: Release metric_events rblist

We don't release metric_events rblist, add the missing delete hook and
call the release before leaving cmd_stat.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200602214741.1218986-11-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-stat.c

@@ -2307,6 +2307,7 @@ int cmd_stat(int argc, const char **argv)
 
 	evlist__delete(evsel_list);
 
+	metricgroup__rblist_exit(&stat_config.metric_events);
 	runtime_stat_delete(&stat_config);
 
 	return status;

tools/perf/util/metricgroup.c

@@ -76,11 +76,30 @@ static struct rb_node *metric_event_new(struct rblist *rblist __maybe_unused,
 	return &me->nd;
 }
 
+static void metric_event_delete(struct rblist *rblist __maybe_unused,
+				struct rb_node *rb_node)
+{
+	struct metric_event *me = container_of(rb_node, struct metric_event, nd);
+	struct metric_expr *expr, *tmp;
+
+	list_for_each_entry_safe(expr, tmp, &me->head, nd) {
+		free(expr);
+	}
+
+	free(me);
+}
+
 static void metricgroup__rblist_init(struct rblist *metric_events)
 {
 	rblist__init(metric_events);
 	metric_events->node_cmp = metric_event_cmp;
 	metric_events->node_new = metric_event_new;
+	metric_events->node_delete = metric_event_delete;
+}
+
+void metricgroup__rblist_exit(struct rblist *metric_events)
+{
+	rblist__exit(metric_events);
 }
 
 struct egroup {

tools/perf/util/metricgroup.h

@@ -47,4 +47,5 @@ void metricgroup__print(bool metrics, bool groups, char *filter,
 			bool raw, bool details);
 bool metricgroup__has_metric(const char *metric);
 int arch_get_runtimeparam(void);
+void metricgroup__rblist_exit(struct rblist *metric_events);
 #endif