On Sat, 2017-09-16 at 00:44 +0800, Ming Lei wrote:
> blk-mq will rerun queue via RESTART after one request is completion,
> so not necessary to wait random time for requeuing, it should trust
> blk-mq to do it.
>
> Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
> ---
> drivers/md/dm-mpath.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
> index 96aedaac2c64..f5a1088a6e79 100644
> --- a/drivers/md/dm-mpath.c
> +++ b/drivers/md/dm-mpath.c
> @@ -505,7 +505,7 @@ static int multipath_clone_and_map(struct dm_target *ti, struct request *rq,
> atomic_inc(&m->pg_init_in_progress);
> activate_or_offline_path(pgpath);
> }
> - return DM_MAPIO_DELAY_REQUEUE;
> + return DM_MAPIO_REQUEUE;
> }
> clone->bio = clone->biotail = NULL;
> clone->rq_disk = bdev->bd_disk;
So you are reverting the patch below? Thank you very much.
commit 1c23484c355ec360ca2f37914f8a4802c6baeead
Author: Bart Van Assche <bart.vanassche@xxxxxxx>
Date: Wed Aug 9 11:32:12 2017 -0700
dm mpath: do not lock up a CPU with requeuing activity
When using the block layer in single queue mode, get_request()
returns ERR_PTR(-EAGAIN) if the queue is dying and the REQ_NOWAIT
flag has been passed to get_request(). Avoid that the kernel
reports soft lockup complaints in this case due to continuous
requeuing activity.
Fixes: 7083abbbf ("dm mpath: avoid that path removal can trigger an infinite loop")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx>
Tested-by: Laurence Oberman <loberman@xxxxxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
