perf tools: Initialize reference counts in map__clone()

Commit-ID:  66671d001aeb525b9101e0ccb9062627539de555
Gitweb:     http://git.kernel.org/tip/66671d001aeb525b9101e0ccb9062627539de555
Author:     Arnaldo Carvalho de Melo <[email protected]>
AuthorDate: Tue, 18 Aug 2015 15:19:50 -0300
Committer:  Arnaldo Carvalho de Melo <[email protected]>
CommitDate: Fri, 21 Aug 2015 12:39:30 -0300

perf tools: Initialize reference counts in map__clone()

Map clone was written before we introduced reference counts for maps and dsos, so all that was needed was just a copy and then we would insert it into the new map_groups instance.

Fix it by, after copying, initializing the map->refcnt, grabbing a struct dso refcount and resetting pointers that may be used to determine if a map, when deleted, is in a rb_tree.

---
 tools/perf/util/map.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

index ce37e95..b1c475d 100644
@@ -348,9 +348,18 @@ struct symbol *map__find_symbol_by_name(struct map *map, const char *name,
 	return dso__find_symbol_by_name(map->dso, map->type, name);
 }
 
-struct map *map__clone(struct map *map)
+struct map *map__clone(struct map *from)
 {
-	return memdup(map, sizeof(*map));
+	struct map *map = memdup(from, sizeof(*map));
+
+	if (map != NULL) {
+		atomic_set(&map->refcnt, 1);
+		RB_CLEAR_NODE(&map->rb_node);
+		dso__get(map->dso);
+		map->groups = NULL;
+	}
+
+	return map;
 }
 
 int map__overlap(struct map *l, struct map *r)