Em Wed, May 22, 2019 at 02:32:48PM +0900, Namhyung Kim escreveu:
> 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 <[email protected]>
> ---
> 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);
> +
Humm, so we need to change thread__namespaces() to remove that const
instead of throwing it away with that cast, right?
- Arnaldo
> + 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)
> --
> 2.21.0.1020.gf2820cf01a-goog
--
- Arnaldo
