block: don't delay blk_run_queue_async

Let's check a scenario: 1. blk_delay_queue(q, SCSI_QUEUE_DELAY); 2. blk_run_queue_async(); the second one will became a noop, because q->delay_work already has WORK_STRUCT_PENDING_BIT set, so the delayed work will still run after SCSI_QUEUE_DELAY. But blk_run_queue_async actually hopes the delayed work runs immediately. Fix this by doing a cancel on potentially pending delayed work before queuing an immediate run of the workqueue. Signed-off-by: Shaohua Li <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
cbmeeks · May 18, 2011 · 3ec717b · 3ec717b
1 parent 9937a5e
commit 3ec717b
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/block/blk-core.c b/block/blk-core.c
@@ -316,8 +316,10 @@ EXPORT_SYMBOL(__blk_run_queue);
  */
 void blk_run_queue_async(struct request_queue *q)
 {
-	if (likely(!blk_queue_stopped(q)))
+	if (likely(!blk_queue_stopped(q))) {
+		__cancel_delayed_work(&q->delay_work);
 		queue_delayed_work(kblockd_workqueue, &q->delay_work, 0);
+	}
 }
 EXPORT_SYMBOL(blk_run_queue_async);