perf thread_map: Introduce thread_map__reset function

We need to reset newly allocated 'struct thread_map_data' entries,
because we will introduce new comm memeber, which will get set later or
not at all.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1435310967-14570-2-git-send-email-jolsa@kernel.org
[ Use sizeof(map->map[0]) to be independent of the array entry type ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/thread_map.c b/tools/perf/util/thread_map.c
index 368cc58c6892c57200e79a4f3a0c380114f35f42..ed76c179cf4e13a7125a050960e96b03ef468155 100644 (file)
--- a/tools/perf/util/thread_map.c
+++ b/tools/perf/util/thread_map.c
@@ -21,11 +21,26 @@ static int filter(const struct dirent *dir)
                return 1;
 }
 
+static void thread_map__reset(struct thread_map *map, int start, int nr)
+{
+       size_t size = (nr - start) * sizeof(map->map[0]);
+
+       memset(&map->map[start], 0, size);
+}
+
 static struct thread_map *thread_map__realloc(struct thread_map *map, int nr)
 {
        size_t size = sizeof(*map) + sizeof(map->map[0]) * nr;
+       int start = map ? map->nr : 0;
 
-       return realloc(map, size);
+       map = realloc(map, size);
+       /*
+        * We only realloc to add more items, let's reset new items.
+        */
+       if (map)
+               thread_map__reset(map, start, nr);
+
+       return map;
 }
 
 #define thread_map__alloc(__nr) thread_map__realloc(NULL, __nr)