[PATCH 2/3] blk-mq: Avoid that blk_mq_delay_run_hw_queue() introduces unintended delays

[Bart Van Assche]

Make sure that calling blk_mq_run_hw_queue() or
blk_mq_kick_requeue_list() triggers a queue run without delay even
if blk_mq_delay_run_hw_queue() has been called recently and if its
delay has not yet expired.

Signed-off-by: Bart Van Assche <bart.vanass...@wdc.com>
---
 block/blk-mq.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 6859b5492509..01f271d40825 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -787,7 +787,7 @@ EXPORT_SYMBOL(blk_mq_add_to_requeue_list);
 
 void blk_mq_kick_requeue_list(struct request_queue *q)
 {
-       kblockd_schedule_delayed_work(&q->requeue_work, 0);
+       kblockd_mod_delayed_work_on(WORK_CPU_UNBOUND, &q->requeue_work, 0);
 }
 EXPORT_SYMBOL(blk_mq_kick_requeue_list);
 
@@ -1403,9 +1403,8 @@ static void __blk_mq_delay_run_hw_queue(struct 
blk_mq_hw_ctx *hctx, bool async,
                put_cpu();
        }
 
-       kblockd_schedule_delayed_work_on(blk_mq_hctx_next_cpu(hctx),
-                                        &hctx->run_work,
-                                        msecs_to_jiffies(msecs));
+       kblockd_mod_delayed_work_on(blk_mq_hctx_next_cpu(hctx), &hctx->run_work,
+                                   msecs_to_jiffies(msecs));
 }
 
 void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs)
-- 
2.15.1