3 files changed, 17 insertions, 1 deletions

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index ae4c5e12debd..ba5f5c0c838b 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -323,6 +323,7 @@ void map_groups__init(struct map_groups *mg)
                 INIT_LIST_HEAD(&mg->removed_maps[i]);
         }
         mg->machine = NULL;
+        mg->refcnt = 1;
 }
 
 static void maps__delete(struct rb_root *maps)
@@ -374,6 +375,12 @@ void map_groups__delete(struct map_groups *mg)
         free(mg);
 }
 
+void map_groups__put(struct map_groups *mg)
+{
+        if (--mg->refcnt == 0)
+                map_groups__delete(mg);
+}
+
 void map_groups__flush(struct map_groups *mg)
 {
         int type;
diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h
index 1073e2d8b797..d6445b27d672 100644
--- a/tools/perf/util/map.h
+++ b/tools/perf/util/map.h
@@ -59,11 +59,20 @@ struct map_groups {
         struct rb_root   maps[MAP__NR_TYPES];
         struct list_head removed_maps[MAP__NR_TYPES];
         struct machine   *machine;
+        int              refcnt;
 };
 
 struct map_groups *map_groups__new(void);
 void map_groups__delete(struct map_groups *mg);
 
+static inline struct map_groups *map_groups__get(struct map_groups *mg)
+{
+        ++mg->refcnt;
+        return mg;
+}
+
+void map_groups__put(struct map_groups *mg);
+
 static inline struct kmap *map__kmap(struct map *map)
 {
         return (struct kmap *)(map + 1);
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index dc51d1632e92..b501848a8424 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -50,7 +50,7 @@ void thread__delete(struct thread *thread)
 {
         struct comm *comm, *tmp;
 
-        map_groups__delete(thread->mg);
+        map_groups__put(thread->mg);
         thread->mg = NULL;
         list_for_each_entry_safe(comm, tmp, &thread->comm_list, list) {
                 list_del(&comm->list);