[PATCH 07/30] perf tools: Add reference counting for thread_map object

Jiri Olsa
2015-06-14T08:27:20Z

Adding refference counting for thread_map object, so
it could be easily shared among other objects.

Using thread_map__put instead thread_map__delete and making
thread_map__delete static.

Link: http://lkml.kernel.org/n/tip-myadl53clbkjvzeqolwp95w0@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/perf/tests/code-reading.c | 2 +-
tools/perf/tests/keep-tracking.c | 2 +-
tools/perf/tests/mmap-basic.c | 2 +-
tools/perf/tests/mmap-thread-lookup.c | 2 +-
tools/perf/tests/openat-syscall-all-cpus.c | 2 +-
tools/perf/tests/openat-syscall.c | 2 +-
tools/perf/tests/switch-tracking.c | 2 +-
tools/perf/util/evlist.c | 4 ++--
tools/perf/util/python.c | 2 +-
tools/perf/util/thread_map.c | 30 ++++++++++++++++++++++++++----
tools/perf/util/thread_map.h | 7 +++++--
11 files changed, 41 insertions(+), 16 deletions(-)

diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c
index 86d17d2e9e50..7dcd2c3d865f 100644
--- a/tools/perf/tests/code-reading.c
+++ b/tools/perf/tests/code-reading.c
@@ -546,7 +546,7 @@ out_err:
perf_evlist__delete(evlist);
} else {
cpu_map__put(cpus);
- thread_map__delete(threads);
+ thread_map__put(threads);
}
machines__destroy_kernel_maps(&machines);
machine__delete_threads(machine);
diff --git a/tools/perf/tests/keep-tracking.c b/tools/perf/tests/keep-tracking.c
index a330235cefc0..4d4b9837b630 100644
--- a/tools/perf/tests/keep-tracking.c
+++ b/tools/perf/tests/keep-tracking.c
@@ -145,7 +145,7 @@ out_err:
perf_evlist__delete(evlist);
} else {
cpu_map__put(cpus);
- thread_map__delete(threads);
+ thread_map__put(threads);
}

return err;
diff --git a/tools/perf/tests/mmap-basic.c b/tools/perf/tests/mmap-basic.c
index 5a9ef5833452..666b67a4df9d 100644
--- a/tools/perf/tests/mmap-basic.c
+++ b/tools/perf/tests/mmap-basic.c
@@ -142,6 +142,6 @@ out_delete_evlist:
out_free_cpus:
cpu_map__put(cpus);
out_free_threads:
- thread_map__delete(threads);
+ thread_map__put(threads);
return err;
}
diff --git a/tools/perf/tests/mmap-thread-lookup.c b/tools/perf/tests/mmap-thread-lookup.c
index 264e215c0d36..412a41eb3f81 100644
--- a/tools/perf/tests/mmap-thread-lookup.c
+++ b/tools/perf/tests/mmap-thread-lookup.c
@@ -143,7 +143,7 @@ static int synth_process(struct machine *machine)
perf_event__process,
machine, 0);

- thread_map__delete(map);
+ thread_map__put(map);
return err;
}

diff --git a/tools/perf/tests/openat-syscall-all-cpus.c b/tools/perf/tests/openat-syscall-all-cpus.c
index e34dfdf96b5a..8801983a38f0 100644
--- a/tools/perf/tests/openat-syscall-all-cpus.c
+++ b/tools/perf/tests/openat-syscall-all-cpus.c
@@ -110,6 +110,6 @@ out_close_fd:
out_evsel_delete:
perf_evsel__delete(evsel);
out_thread_map_delete:
- thread_map__delete(threads);
+ thread_map__put(threads);
return err;
}
diff --git a/tools/perf/tests/openat-syscall.c b/tools/perf/tests/openat-syscall.c
index 9f9491bb8e48..bdfa1f446681 100644
--- a/tools/perf/tests/openat-syscall.c
+++ b/tools/perf/tests/openat-syscall.c
@@ -56,6 +56,6 @@ out_close_fd:
out_evsel_delete:
perf_evsel__delete(evsel);
out_thread_map_delete:
- thread_map__delete(threads);
+ thread_map__put(threads);
return err;
}
diff --git a/tools/perf/tests/switch-tracking.c b/tools/perf/tests/switch-tracking.c
index 1b06122beb76..e698742d4fec 100644
--- a/tools/perf/tests/switch-tracking.c
+++ b/tools/perf/tests/switch-tracking.c
@@ -561,7 +561,7 @@ out:
perf_evlist__delete(evlist);
} else {
cpu_map__put(cpus);
- thread_map__delete(threads);
+ thread_map__put(threads);
}

return err;
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index bd747215caa4..f7d80ca58136 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -115,7 +115,7 @@ void perf_evlist__delete(struct perf_evlist *evlist)
perf_evlist__munmap(evlist);
perf_evlist__close(evlist);
cpu_map__put(evlist->cpus);
- thread_map__delete(evlist->threads);
+ thread_map__put(evlist->threads);
evlist->cpus = NULL;
evlist->threads = NULL;
perf_evlist__purge(evlist);
@@ -1104,7 +1104,7 @@ int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)
return 0;

out_delete_threads:
- thread_map__delete(evlist->threads);
+ thread_map__put(evlist->threads);
evlist->threads = NULL;
return -1;
}
diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
index b106d56df240..626422eda727 100644
--- a/tools/perf/util/python.c
+++ b/tools/perf/util/python.c
@@ -453,7 +453,7 @@ static int pyrf_thread_map__init(struct pyrf_thread_map *pthreads,

static void pyrf_thread_map__delete(struct pyrf_thread_map *pthreads)
{
- thread_map__delete(pthreads->threads);
+ thread_map__put(pthreads->threads);
pthreads->ob_type->tp_free((PyObject*)pthreads);
}

diff --git a/tools/perf/util/thread_map.c b/tools/perf/util/thread_map.c
index f7a49a693d27..584fa978e50a 100644
--- a/tools/perf/util/thread_map.c
+++ b/tools/perf/util/thread_map.c
@@ -9,6 +9,7 @@
#include "strlist.h"
#include <string.h>
#include <api/fs/fs.h>
+#include "asm/bug.h"
#include "thread_map.h"
#include "util.h"
#include "debug.h"
@@ -89,6 +90,7 @@ struct thread_map *thread_map__new_by_pid(pid_t pid)
comm_init(threads, i);
}
threads->nr = items;
+ atomic_set(&threads->refcnt, 1);
}

for (i=0; i<items; i++)
@@ -106,6 +108,7 @@ struct thread_map *thread_map__new_by_tid(pid_t tid)
thread_map__pid(threads, 0) = tid;
threads->nr = 1;
comm_init(threads, 0);
+ atomic_set(&threads->refcnt, 1);
}

return threads;
@@ -127,6 +130,7 @@ struct thread_map *thread_map__new_by_uid(uid_t uid)
goto out_free_threads;

threads->nr = 0;
+ atomic_set(&threads->refcnt, 1);

while (!readdir_r(proc, &dirent, &next) && next) {
char *end;
@@ -256,6 +260,8 @@ static struct thread_map *thread_map__new_by_pid_str(const char *pid_str)

out:
strlist__delete(slist);
+ if (threads)
+ atomic_set(&threads->refcnt, 1);
return threads;

out_free_namelist:
@@ -276,6 +282,7 @@ struct thread_map *thread_map__new_dummy(void)
thread_map__pid(threads, 0) = -1;
threads->nr = 1;
comm_init(threads, 0);
+ atomic_set(&threads->refcnt, 1);
}
return threads;
}
@@ -319,6 +326,8 @@ static struct thread_map *thread_map__new_by_tid_str(const char *tid_str)
comm_init(threads, ntasks - 1);
}
out:
+ if (threads)
+ atomic_set(&threads->refcnt, 1);
return threads;

out_free_threads:
@@ -338,16 +347,29 @@ struct thread_map *thread_map__new_str(const char *pid, const char *tid,
return thread_map__new_by_tid_str(tid);
}

-void thread_map__delete(struct thread_map *threads)
+static void thread_map__delete(struct thread_map *threads)
{
- int i;
-
if (threads) {
+ int i;
+
+ WARN_ONCE(atomic_read(&threads->refcnt) != 0,
+ "thread map refcnt disbalanced\n");
for (i = 0; i < threads->nr; i++)
free(thread_map__comm(threads, i));
+ free(threads);
}
+}

- free(threads);
+struct thread_map *thread_map__get(struct thread_map *map)
+{
+ atomic_inc(&map->refcnt);
+ return map;
+}
+
+void thread_map__put(struct thread_map *map)
+{
+ if (map && atomic_dec_and_test(&map->refcnt))
+ thread_map__delete(map);
}

size_t thread_map__fprintf(struct thread_map *threads, FILE *fp)
diff --git a/tools/perf/util/thread_map.h b/tools/perf/util/thread_map.h
index 6933f9d316d9..91207cee7294 100644
--- a/tools/perf/util/thread_map.h
+++ b/tools/perf/util/thread_map.h
@@ -3,6 +3,7 @@

#include <sys/types.h>
#include <stdio.h>
+#include <linux/atomic.h>

struct thread_map_data {
pid_t pid;
@@ -10,6 +11,7 @@ struct thread_map_data {
};

struct thread_map {
+ atomic_t refcnt;
int nr;
struct thread_map_data map[];
};
@@ -23,11 +25,12 @@ 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(pid_t pid, pid_t tid, uid_t uid);

+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);

-void thread_map__delete(struct thread_map *threads);
-
size_t thread_map__fprintf(struct thread_map *threads, FILE *fp);

static inline int thread_map__nr(struct thread_map *threads)
--
1.9.3