Re: [PATCH 02/24] io-controller: Core of the elevator fair queuing

[Gui Jianfeng <guijianfeng@cn.fujitsu.com>]

Vivek Goyal wrote:
...
> +
> +static void put_prev_io_entity(struct io_entity *entity)
> +{
> +	struct io_service_tree *st = entity->st;
> +	struct io_sched_data *sd = io_entity_sched_data(entity);
> +
> +	st->active_entity = NULL;
> +	sd->active_entity = NULL;
> +
> +	if (unlikely(entity->ioprio_changed)) {
> +		dequeue_io_entity(entity);
> +		io_entity_update_prio(entity);

Hi Vivek,

we don't need to update prio here for the following enqueue_io_entity() 
is already taking care of it.

Signed-off-by: Gui Jianfeng <guijianfeng@cn.fujitsu.com>
---
 block/elevator-fq.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/block/elevator-fq.c b/block/elevator-fq.c
index 201543e..b720139 100644
--- a/block/elevator-fq.c
+++ b/block/elevator-fq.c
@@ -607,7 +607,6 @@ static void put_prev_io_entity(struct io_entity *entity)
 
 	if (unlikely(entity->ioprio_changed)) {
 		dequeue_io_entity(entity);
-		io_entity_update_prio(entity);
 		enqueue_io_entity(entity);
 	} else
 		__enqueue_io_entity(st, entity);
-- 
1.5.4.rc3