[PATCH 1/3] block: Requeue req as head if driver touched it

From: Christian Löhle
Date: Wed Oct 26 2022 - 03:31:01 EST


In case the driver set RQF_DONTPREP flag, requeue the request as head as
it is likely that the backing storage already had a request to an
adjacent region, so getting the requeued request out as soon as possible
may give us some performance benefit.

Signed-off-by: Christian Loehle <cloehle@xxxxxxxxxxxxxx>
---
block/blk-mq.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 33292c01875d..d863c826fb23 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1429,7 +1429,7 @@ static void blk_mq_requeue_work(struct work_struct *work)
* merge.
*/
if (rq->rq_flags & RQF_DONTPREP)
- blk_mq_request_bypass_insert(rq, false, false);
+ blk_mq_request_bypass_insert(rq, true, false);
else
blk_mq_sched_insert_request(rq, true, false, false);
}
--
2.37.3
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