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| author | Namhyung Kim <namhyung@kernel.org> | 2019-05-22 14:32:48 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-22 08:15:19 +0200 |
| commit | be0e62666da159dcbabe61c90e1056f2b964046f (patch) | |
| tree | 43a6f942fccebcb1dcfcec3ea86c8fe0a5673374 | |
| parent | 7d523e33f4b6fce626577075d188419081bef2b0 (diff) | |
| download | linux-rpi3-be0e62666da159dcbabe61c90e1056f2b964046f.tar.gz linux-rpi3-be0e62666da159dcbabe61c90e1056f2b964046f.tar.bz2 linux-rpi3-be0e62666da159dcbabe61c90e1056f2b964046f.zip | |
perf namespace: Protect reading thread's namespace
[ Upstream commit 6584140ba9e6762dd7ec73795243289b914f31f9 ]
It seems that the current code lacks holding the namespace lock in
thread__namespaces(). Otherwise it can see inconsistent results.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Hari Bathini <hbathini@linux.vnet.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Link: http://lkml.kernel.org/r/20190522053250.207156-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | tools/perf/util/thread.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index 2048d393ece6..56007a7e0b4d 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -128,7 +128,7 @@ void thread__put(struct thread *thread) } } -struct namespaces *thread__namespaces(const struct thread *thread) +static struct namespaces *__thread__namespaces(const struct thread *thread) { if (list_empty(&thread->namespaces_list)) return NULL; @@ -136,10 +136,21 @@ struct namespaces *thread__namespaces(const struct thread *thread) return list_first_entry(&thread->namespaces_list, struct namespaces, list); } +struct namespaces *thread__namespaces(const struct thread *thread) +{ + struct namespaces *ns; + + down_read((struct rw_semaphore *)&thread->namespaces_lock); + ns = __thread__namespaces(thread); + up_read((struct rw_semaphore *)&thread->namespaces_lock); + + return ns; +} + static int __thread__set_namespaces(struct thread *thread, u64 timestamp, struct namespaces_event *event) { - struct namespaces *new, *curr = thread__namespaces(thread); + struct namespaces *new, *curr = __thread__namespaces(thread); new = namespaces__new(event); if (!new) |