[PATCH v4 10/12] perf util: Reuse thread_map__new_by_uid to enumerate threads from /proc

[Jin Yao]

Perf already has a function thread_map__new_by_uid() which can
enumerate all threads from /proc by uid.

This patch creates a static function enumerate_threads() which
reuses the common code in thread_map__new_by_uid() to enumerate
threads from /proc.

The enumerate_threads() is shared by thread_map__new_by_uid()
and a new function thread_map__new_threads().

The new function thread_map__new_threads() is called to enumerate
all threads from /proc.

Signed-off-by: Jin Yao <yao.jin@xxxxxxxxxxxxxxx>
---
 tools/perf/tests/thread-map.c |  2 +-
 tools/perf/util/evlist.c      |  3 ++-
 tools/perf/util/thread_map.c  | 19 ++++++++++++++++---
 tools/perf/util/thread_map.h  |  3 ++-
 4 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/tools/perf/tests/thread-map.c b/tools/perf/tests/thread-map.c
index dbcb6a1..4de1939 100644
--- a/tools/perf/tests/thread-map.c
+++ b/tools/perf/tests/thread-map.c
@@ -105,7 +105,7 @@ int test__thread_map_remove(struct test *test __maybe_unused, int subtest __mayb
 	TEST_ASSERT_VAL("failed to allocate map string",
 			asprintf(&str, "%d,%d", getpid(), getppid()) >= 0);
 
-	threads = thread_map__new_str(str, NULL, 0);
+	threads = thread_map__new_str(str, NULL, 0, false);
 
 	TEST_ASSERT_VAL("failed to allocate thread_map",
 			threads);
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 199bb82..05b8f2b 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -1102,7 +1102,8 @@ int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)
 	struct cpu_map *cpus;
 	struct thread_map *threads;
 
-	threads = thread_map__new_str(target->pid, target->tid, target->uid);
+	threads = thread_map__new_str(target->pid, target->tid, target->uid,
+				      target->per_thread);
 
 	if (!threads)
 		return -1;
diff --git a/tools/perf/util/thread_map.c b/tools/perf/util/thread_map.c
index be0d5a7..5672268 100644
--- a/tools/perf/util/thread_map.c
+++ b/tools/perf/util/thread_map.c
@@ -92,7 +92,7 @@ struct thread_map *thread_map__new_by_tid(pid_t tid)
 	return threads;
 }
 
-struct thread_map *thread_map__new_by_uid(uid_t uid)
+static struct thread_map *enumerate_threads(uid_t uid)
 {
 	DIR *proc;
 	int max_threads = 32, items, i;
@@ -124,7 +124,7 @@ struct thread_map *thread_map__new_by_uid(uid_t uid)
 		if (stat(path, &st) != 0)
 			continue;
 
-		if (st.st_uid != uid)
+		if ((uid != UINT_MAX) && (st.st_uid != uid))
 			continue;
 
 		snprintf(path, sizeof(path), "/proc/%d/task", pid);
@@ -178,6 +178,16 @@ struct thread_map *thread_map__new_by_uid(uid_t uid)
 	goto out_closedir;
 }
 
+struct thread_map *thread_map__new_by_uid(uid_t uid)
+{
+	return enumerate_threads(uid);
+}
+
+struct thread_map *thread_map__new_threads(void)
+{
+	return enumerate_threads(UINT_MAX);
+}
+
 struct thread_map *thread_map__new(pid_t pid, pid_t tid, uid_t uid)
 {
 	if (pid != -1)
@@ -313,7 +323,7 @@ struct thread_map *thread_map__new_by_tid_str(const char *tid_str)
 }
 
 struct thread_map *thread_map__new_str(const char *pid, const char *tid,
-				       uid_t uid)
+				       uid_t uid, bool per_thread)
 {
 	if (pid)
 		return thread_map__new_by_pid_str(pid);
@@ -321,6 +331,9 @@ struct thread_map *thread_map__new_str(const char *pid, const char *tid,
 	if (!tid && uid != UINT_MAX)
 		return thread_map__new_by_uid(uid);
 
+	if (per_thread)
+		return thread_map__new_threads();
+
 	return thread_map__new_by_tid_str(tid);
 }
 
diff --git a/tools/perf/util/thread_map.h b/tools/perf/util/thread_map.h
index f158039..dc07543 100644
--- a/tools/perf/util/thread_map.h
+++ b/tools/perf/util/thread_map.h
@@ -23,6 +23,7 @@ struct thread_map *thread_map__new_dummy(void);
 struct thread_map *thread_map__new_by_pid(pid_t pid);
 struct thread_map *thread_map__new_by_tid(pid_t tid);
 struct thread_map *thread_map__new_by_uid(uid_t uid);
+struct thread_map *thread_map__new_threads(void);
 struct thread_map *thread_map__new(pid_t pid, pid_t tid, uid_t uid);
 struct thread_map *thread_map__new_event(struct thread_map_event *event);
 
@@ -30,7 +31,7 @@ struct thread_map *thread_map__get(struct thread_map *map);
 void thread_map__put(struct thread_map *map);
 
 struct thread_map *thread_map__new_str(const char *pid,
-		const char *tid, uid_t uid);
+		const char *tid, uid_t uid, bool per_thread);
 
 struct thread_map *thread_map__new_by_tid_str(const char *tid_str);
 
-- 
2.7.4