Re: [PATCH -tip] sched/wake_q: Clarify queue reinit

From: Waiman Long
Date: Sun Jan 29 2017 - 11:25:22 EST


On 01/29/2017 10:15 AM, Davidlohr Bueso wrote:
> As of bcc9a76d5ac (locking/rwsem: Reinit wake_q after use), the
> comment regarding the list reinitialization no longer applies,
> update it with the new wake_q_init() helper.
>
> Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
> ---
> include/linux/sched.h | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/sched.h b/include/linux/sched.h
> index 3640bde9f982..c0bc626c531f 100644
> --- a/include/linux/sched.h
> +++ b/include/linux/sched.h
> @@ -998,8 +998,8 @@ enum cpu_idle_type {
> *
> * The DEFINE_WAKE_Q macro declares and initializes the list head.
> * wake_up_q() does NOT reinitialize the list; it's expected to be
> - * called near the end of a function, where the fact that the queue is
> - * not used again will be easy to see by inspection.
> + * called near the end of a function. Otherwise, the list can be
> + * re-initialized for later re-use by wake_q_init().
> *
> * Note that this can cause spurious wakeups. schedule() callers
> * must ensure the call is done inside a loop, confirming that the

Acked-by: Waiman Long <longman@xxxxxxxxxx>