[PATCH v2 08/10] perf util: Reuse thread_map__new_by_uid to enumerate threads from /proc

Jin Yao
2017-11-27T06:13:08Z

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@linux.intel.com>
---
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