1 files changed, 43 insertions, 0 deletions
diff --git a/tools/perf/lib/threadmap.c b/tools/perf/lib/threadmap.c
index 163dc609b909..23e628a1437a 100644
--- a/tools/perf/lib/threadmap.c
+++ b/tools/perf/lib/threadmap.c
@@ -3,3 +3,46 @@
 #include <stdlib.h>
 #include <linux/refcount.h>
 #include <internal/threadmap.h>
+#include <string.h>
+
+static void perf_thread_map__reset(struct perf_thread_map *map, int start, int nr)
+{
+	size_t size = (nr - start) * sizeof(map->map[0]);
+
+	memset(&map->map[start], 0, size);
+	map->err_thread = -1;
+}
+
+struct perf_thread_map *perf_thread_map__realloc(struct perf_thread_map *map, int nr)
+{
+	size_t size = sizeof(*map) + sizeof(map->map[0]) * nr;
+	int start = map ? map->nr : 0;
+
+	map = realloc(map, size);
+	/*
+	 * We only realloc to add more items, let's reset new items.
+	 */
+	if (map)
+		perf_thread_map__reset(map, start, nr);
+
+	return map;
+}
+
+#define thread_map__alloc(__nr) perf_thread_map__realloc(NULL, __nr)
+
+void perf_thread_map__set_pid(struct perf_thread_map *map, int thread, pid_t pid)
+{
+	map->map[thread].pid = pid;
+}
+
+struct perf_thread_map *perf_thread_map__new_dummy(void)
+{
+	struct perf_thread_map *threads = thread_map__alloc(1);
+
+	if (threads != NULL) {
+		perf_thread_map__set_pid(threads, 0, -1);
+		threads->nr = 1;
+		refcount_set(&threads->refcnt, 1);
+	}
+	return threads;
+}