Re: scsi-debug regression with 4.5-rc?

2016-03-05 Thread Martin K. Petersen 
> "Mike" == Mike Snitzer  writes:

Mike> Seems not, I think that BZ may be due to the LBPRZ clause in
Mike> commit 397737223 ("sd: Make discard granularity match logical
Mike> block size when LBPRZ=1") ?

Mike> should be: q->limits.discard_granularity = 1 * logical_block_size;

*blush*

Will fix.

-- 
Martin K. Petersen  Oracle Linux Engineering
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: scsi-debug regression with 4.5-rc?

2016-03-04 Thread Mike Snitzer 
On Wed, Jan 20 2016 at 10:57am -0500,
Martin K. Petersen  wrote:

> > "Ewan" == Ewan Milne  writes:
> 
> Ewan> So I have a report from our test people that the optimal_io_size
> Ewan> sysfs value is now different by a factor of 512 from what it used
> Ewan> to be...
> 
> Yes, just prepared a patch this morning. I messed up sectors vs. bytes.

Would your fix (commit d0eb20a863ba7dc) address this BZ too?
https://bugzilla.redhat.com/show_bug.cgi?id=1314687

Seems not, I think that BZ may be due to the LBPRZ clause in commit
397737223 ("sd: Make discard granularity match logical block size when 
LBPRZ=1") ?

should be: q->limits.discard_granularity = 1 * logical_block_size;

Mike
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: scsi-debug regression with 4.5-rc?

2016-01-20 Thread Ewan Milne 
So I have a report from our test people that the optimal_io_size sysfs
value is now different by a factor of 512 from what it used to be...

>Here is what is executed:
>
>modprobe scsi_debug dev_size_mb=32 sector_size=4096 opt_blks=64
>num_tgts=1
>
>And here is what our test is capturing:
>
>/sys/dev/block/8:0/queue/optimal_io_size = 512 differs from expected
>value 
>1048576!
>
>
>(So with 64 it's 512,  with opt_blks=256 it's 2048,  but it used to be
>1048576)

This looks like it might be due to commit:

commit ca369d51b3e1649be4a72addd6d6a168cfb3f537
Author: Martin K. Petersen 
Date:   Fri Nov 13 16:46:48 2015 -0500

block/sd: Fix device-imposed transfer length limits

It would appear that this commit has changed the meaning of
the queue limits io_opt field to be 512-byte normalized
sectors instead of bytes.  Parts of the diff:

-   blk_queue_io_opt(sdkp->disk->queue,
-get_unaligned_be32([12]) * sector_sz);

...

+   sdkp->opt_xfer_blocks = get_unaligned_be32([12]);

...

+   if (sdkp->opt_xfer_blocks && sdkp->opt_xfer_blocks <= dev_max &&
+   sdkp->opt_xfer_blocks <= SD_DEF_XFER_BLOCKS)
+   rw_max = q->limits.io_opt =
+   logical_to_sectors(sdp, sdkp->opt_xfer_blocks);
+   else
+   rw_max = BLK_DEF_MAX_SECTORS;


---

Was this intentional?  I would have thought we would not want to change
the usermode meaning of this field.

-Ewan


--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: scsi-debug regression with 4.5-rc?

2016-01-20 Thread Martin K. Petersen 
> "Ewan" == Ewan Milne  writes:

Ewan> So I have a report from our test people that the optimal_io_size
Ewan> sysfs value is now different by a factor of 512 from what it used
Ewan> to be...

Yes, just prepared a patch this morning. I messed up sectors vs. bytes.

-- 
Martin K. Petersen  Oracle Linux Engineering
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html