Re: [PATCH] CFQ: clear wait_request flag if needed

[Jens Axboe <jens.axboe@oracle.com>]

On Fri, Aug 21 2009, Gui Jianfeng wrote:
> Hi Jens,
> 
> IMHO wait_request flag should be cleared if a request goes in
> and idle timer needs to shut down. Otherwise, it will walk into
> that path every time when a request is enqueued.

That looks correct, deletion of the timer should always be paired with
the clearing of that flag. Applied, thanks!

> 
> Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
> ---
>  block/cfq-iosched.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
> index fd7080e..67f1910 100644
> --- a/block/cfq-iosched.c
> +++ b/block/cfq-iosched.c
> @@ -2093,6 +2093,7 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq,
>  			if (blk_rq_bytes(rq) > PAGE_CACHE_SIZE ||
>  			    cfqd->busy_queues > 1) {
>  				del_timer(&cfqd->idle_slice_timer);
> +				cfq_clear_cfqq_wait_request(cfqq);
>  			__blk_run_queue(cfqd->queue);
>  			}
>  			cfq_mark_cfqq_must_dispatch(cfqq);
> -- 
> 1.5.4.rc3
> 

-- 
Jens Axboe