From: Namhyung Kim <namhy...@kernel.org> 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 <namhy...@kernel.org> Cc: Hari Bathini <hbath...@linux.vnet.ibm.com> Cc: Jiri Olsa <jo...@redhat.com> Cc: Krister Johansen <k...@templeofstupid.com> Link: http://lkml.kernel.org/r/20190522053250.207156-2-namhy...@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/util/thread.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index 403045a2bbea..b413ba5b9835 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -133,7 +133,7 @@ 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; @@ -141,10 +141,21 @@ 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) -- 2.20.1
