On Tue, May 26 2015 at 4:25P -0400,
Junichi Nomura <j-nomura@xxxxxxxxxxxxx> wrote:
> Without kicking queue, requeued request may stay forever in
> the queue if there are no other I/O activities to the device.
>
> The original error had been in v2.6.39 with commit 7eaceaccab5f
> ("block: remove per-queue plugging"), which replaced conditional
> plugging by periodic runqueue.
>
> Commit 9d1deb83d489 in v4.1-rc1 removed the periodic runqueue
> and the problem started to manifest.
>
> Fixes: 9d1deb83d489 ("dm: don't schedule delayed run of the queue if nothing to do")
> Signed-off-by: Jun'ichi Nomura <j-nomura@xxxxxxxxxxxxx>
>
> diff --git a/drivers/md/dm.c b/drivers/md/dm.c
> index a930b72..0bf79a0 100644
> --- a/drivers/md/dm.c
> +++ b/drivers/md/dm.c
> @@ -1164,6 +1164,7 @@ static void old_requeue_request(struct request *rq)
>
> spin_lock_irqsave(q->queue_lock, flags);
> blk_requeue_request(q, rq);
> + blk_run_queue_async(q);
> spin_unlock_irqrestore(q->queue_lock, flags);
> }
Thanks Junichi. The new blk-mq path did kick the queue, but obviously
the old request_fn path didn't. I'll get this queued for 4.1.
Mike
--
dm-devel mailing list
dm-devel@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/dm-devel
