Re: [PATCH V2 0/2] block: remove unnecessary RESTART

[Ming Lei <ming.lei@redhat.com>]

On Tue, Oct 31, 2017 at 07:53:03PM -0600, Jens Axboe wrote:
> 
> > On Oct 31, 2017, at 7:46 PM, Ming Lei <ming.lei@redhat.com> wrote:
> > 
> >> On Tue, Oct 31, 2017 at 02:29:32PM -0600, Jens Axboe wrote:
> >>> On 10/26/2017 10:43 PM, Ming Lei wrote:
> >>> Hi Jens,
> >>> 
> >>> The 1st patch removes the RESTART for TAG-SHARED because SCSI handles it
> >>> by itself, and not necessary to waste CPU to do the expensive RESTART.
> >>> And Roman Pen reported that this RESTART cuts half of IOPS in his case.
> >>> 
> >>> The 2nd patch removes the RESTART when .get_budget returns BLK_STS_RESOURCE,
> >>> and this RESTART is handled by SCSI's RESTART(scsi_end_request()) too.
> >> 
> >> What base is this against?
> > 
> > The for-next branch of your block tree:
> 
> From when? Doesn’t apply at all today. 

I just tried today's for-next(top commit is 'MAINTAINERS: Remove Rafael from Opal maintainers.'),
and the two patches can be applied cleanly.

I guess you may try to apply the two patches against for-4.15/block,
which doesn't include the patchset of '[PATCH V10 0/8] blk-mq-sched: improve sequential I/O'[1]:

	https://marc.info/?t=150797316600002&r=1&w=2

-- 
Ming