Re: [PATCH] locking/percpu-rwsem: Remove WQ_FLAG_EXCLUSIVE flags

From: Will Deacon
Date: Fri Aug 21 2020 - 07:13:57 EST


On Wed, Jul 01, 2020 at 01:57:20PM +0800, qiang.zhang@xxxxxxxxxxxxx wrote:
> From: Zqiang <qiang.zhang@xxxxxxxxxxxxx>
>
> Remove WQ_FLAG_EXCLUSIVE from "wq_entry.flags", using function
> __add_wait_queue_entry_tail_exclusive substitution.
>
> Signed-off-by: Zqiang <qiang.zhang@xxxxxxxxxxxxx>
> ---
> kernel/locking/percpu-rwsem.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/locking/percpu-rwsem.c b/kernel/locking/percpu-rwsem.c
> index 8bbafe3e5203..48e1c55c2e59 100644
> --- a/kernel/locking/percpu-rwsem.c
> +++ b/kernel/locking/percpu-rwsem.c
> @@ -148,8 +148,8 @@ static void percpu_rwsem_wait(struct percpu_rw_semaphore *sem, bool reader)
> */
> wait = !__percpu_rwsem_trylock(sem, reader);
> if (wait) {
> - wq_entry.flags |= WQ_FLAG_EXCLUSIVE | reader * WQ_FLAG_CUSTOM;
> - __add_wait_queue_entry_tail(&sem->waiters, &wq_entry);
> + wq_entry.flags |= reader * WQ_FLAG_CUSTOM;
> + __add_wait_queue_entry_tail_exclusive(&sem->waiters, &wq_entry);
> }
> spin_unlock_irq(&sem->waiters.lock);

Seems straightforward enough:

Acked-by: Will Deacon <will@xxxxxxxxxx>

Will