Re: [PATCH v7 4/4] qrwlock: Use smp_store_release() in write_unlock()

["Paul E. McKenney" <paulmck@linux.vnet.ibm.com>]

On Fri, Nov 22, 2013 at 02:04:47PM -0500, Waiman Long wrote:
> This patch modifies the queue_write_unlock() function to use the
> new smp_store_release() function in another pending patch. This patch
> should only be merged if the other patch was merged.
> 
> Signed-off-by: Waiman Long <Waiman.Long@hp.com>

Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

> ---
>  include/asm-generic/qrwlock.h |    4 +---
>  1 files changed, 1 insertions(+), 3 deletions(-)
> 
> diff --git a/include/asm-generic/qrwlock.h b/include/asm-generic/qrwlock.h
> index 335473a..59c5972 100644
> --- a/include/asm-generic/qrwlock.h
> +++ b/include/asm-generic/qrwlock.h
> @@ -176,9 +176,7 @@ static inline void queue_write_unlock(struct qrwlock *lock)
>  	/*
>  	 * Make sure that none of the critical section will be leaked out.
>  	 */
> -	smp_mb__before_clear_bit();
> -	ACCESS_ONCE(lock->cnts.writer) = 0;
> -	smp_mb__after_clear_bit();
> +	smp_store_release(&lock->cnts.writer, 0)
>  }
> 
>  /*
> -- 
> 1.7.1
>