[dm-devel] [PATCH] IO-Controller: clear ioq wait flag if a request goes into that ioq

[Gui Jianfeng <guijianfeng cn fujitsu com>]

Vivek Goyal wrote:
...
>  		/*
>  		 * Remember that we saw a request from this process, but
> @@ -1940,7 +2013,7 @@ void elv_ioq_request_add(struct request_queue *q, struct request *rq)
>  		 * has other work pending, don't risk delaying until the
>  		 * idle timer unplug to continue working.
>  		 */
> -		if (elv_ioq_wait_request(ioq)) {
> +		if (group_wait || elv_ioq_wait_request(ioq)) {

Hi Vivek,

I guess we need to clear ioq_wait_request flags if there are requests to 
go in this ioq. Otherwise, once waitting request on ioq, it will go into
this path every time when a request is enqueued.

Signed-off-by: Gui Jianfeng <guijianfeng cn fujitsu com>
---
 block/elevator-fq.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/block/elevator-fq.c b/block/elevator-fq.c
index b3c387d..201543e 100644
--- a/block/elevator-fq.c
+++ b/block/elevator-fq.c
@@ -2708,6 +2708,9 @@ void elv_ioq_request_add(struct request_queue *q, struct request *rq)
 				__blk_run_queue(q);
 			else
 				elv_mark_ioq_must_dispatch(ioq);
+
+			if (elv_ioq_wait_request(ioq))
+				elv_clear_ioq_wait_request(ioq);
 		}
 	} else if (elv_should_preempt(q, ioq, rq)) {
 		/*
-- 
1.5.4.rc3