[dm-devel] dm-rq queue stalls

[Bart Van Assche]

On Wed, 2018-01-17 at 14:36 -0500, Mike Snitzer wrote:
> That tree doesn't have the revert you think it does (because it doesn't have _any_ of the dm-4.16 changes).
> 
> So there is some other reason for your hang.

Hello Mike,

Please have another look, namely at the following commit:
https://github.com/bvanassche/linux/commit/cd0b6b9f8779a0b692b1ef1d1f5ba6cb2fd981c5

That contents of that commit is as follows:

Subject: [PATCH] Revert "dm rq: Avoid that request processing stalls sporadically"

This reverts commit 6077c2d706097c00d8f2fed57d3f3c45cd228ee8.
---
 drivers/md/dm-rq.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/md/dm-rq.c b/drivers/md/dm-rq.c
index 85d80b8ccc33..a9e0f6ec62b6 100644
--- a/drivers/md/dm-rq.c
+++ b/drivers/md/dm-rq.c
@@ -773,7 +773,6 @@ static blk_status_t dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
 		/* Undo dm_start_request() before requeuing */
 		rq_end_stats(md, rq);
 		rq_completed(md, rq_data_dir(rq), false);
-		blk_mq_delay_run_hw_queue(hctx, 100/*ms*/);
 		return BLK_STS_RESOURCE;
 	}
 
Thanks,

Bart.