# \[PATCH\] dm: fix parameter to blk\_delay\_queue()

- Subsystems: DEVICE-MAPPER (LVM), THE REST
- Maintainers: Alasdair Kergon, Mike Snitzer, Mikulas Patocka, Benjamin Marzinski, Linus Torvalds
- List: linux-raid
- 3 messages, 2 authors
- Page: https://ratatoskr.run/linux-raid/2016/07/4795877/t

## \[PATCH\] dm: fix parameter to blk\_delay\_queue()

- From: Tahsin Erdogan \<hidden\>
- Date: 2016-07-15 13:27:53 
- Message: https://ratatoskr.run/linux-raid/2016/07/4795877.md

```text
Second parameter to blk_delay_queue() must be in msec units not jiffies.

Signed-off-by: Tahsin Erdogan <redacted>
---
 drivers/md/dm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 1b2f96205361..17c63265a205 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2175,7 +2175,7 @@ static void dm_request_fn(struct request_queue *q)
 		     md_in_flight(md) && rq->bio && rq->bio->bi_vcnt == 1 &&
 		     md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) ||
 		    (ti->type->busy && ti->type->busy(ti))) {
-			blk_delay_queue(q, HZ / 100);
+			blk_delay_queue(q, 10);
 			return;
 		}
 
-- 
2.8.0.rc3.226.g39d4020

```

## Re: dm: fix parameter to blk\_delay\_queue()

- From: Mike Snitzer \<hidden\>
- Date: 2016-07-15 13:59:09 
- Message: https://ratatoskr.run/linux-raid/2016/07/4795892.md

```text
On Fri, Jul 15 2016 at  9:27am -0400,
Tahsin Erdogan [ref] wrote:

> Second parameter to blk_delay_queue() must be in msec units not jiffies.
> 
> Signed-off-by: Tahsin Erdogan <redacted>

This needs to be rebased against linux-next (or linux-dm.git's
'for-next') because the code in question has been moved out to dm-rq.c

But I'll gladly take care of it.

Your change seems fine, and in fact my intent was always to have it be
10 msec, see commit: d548b34b062b60

Curious that the initial "HZ / 10" (from Jens' commit 7eaceaccab) wasn't
expressed in terms of msecs either.

Anyway, thanks for the fix!

Mike

> ---
>  drivers/md/dm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/md/dm.c b/drivers/md/dm.c
> index 1b2f96205361..17c63265a205 100644
> --- a/drivers/md/dm.c
> +++ b/drivers/md/dm.c
> @@ -2175,7 +2175,7 @@ static void dm_request_fn(struct request_queue *q)
>  		     md_in_flight(md) && rq->bio && rq->bio->bi_vcnt == 1 &&
>  		     md->last_rq_pos == pos && md->last_rq_rw == rq_data_dir(rq)) ||
>  		    (ti->type->busy && ti->type->busy(ti))) {
> -			blk_delay_queue(q, HZ / 100);
> +			blk_delay_queue(q, 10);
>  			return;
>  		}
>  
> -- 
> 2.8.0.rc3.226.g39d4020
> 
```

## Re: dm: fix parameter to blk\_delay\_queue()

- From: Tahsin Erdogan \<hidden\>
- Date: 2016-07-15 14:18:10 
- Message: https://ratatoskr.run/linux-raid/2016/07/4795896.md

```text
> This needs to be rebased against linux-next (or linux-dm.git's
> 'for-next') because the code in question has been moved out to dm-rq.c
>
> But I'll gladly take care of it.

Thanks Mike!
```