Re: [PATCH v6 1/3] block: Add iocontext priority to request

[Jens Axboe]

On 10/19/2016 12:05 PM, Tejun Heo wrote:
> Hello,
>
> On Mon, Oct 17, 2016 at 11:27:28AM -0700, Adam Manzanares wrote:
> > Patch adds an association between iocontext ioprio and the ioprio of a
> > request. This is done to enable request based drivers the ability to
> > act on priority information stored in the request. An example being
> > ATA devices that support command priorities. If the ATA driver discovers
> > that the device supports command priorities and the request has valid
> > priority information indicating the request is high priority, then a high
> > priority command can be sent to the device. This should improve tail
> > latencies for high priority IO on any device that queues requests
> > internally and can make use of the priority information stored in the
> > request.
> >
> > The ioprio of the request is set in blk_rq_set_prio which takes the
> > request and the ioc as arguments. If the ioc is valid in blk_rq_set_prio
> > then the iopriority of the request is set as the iopriority of the ioc.
> > In init_request_from_bio a check is made to see if the ioprio of the bio
> > is valid and if so then the request prio comes from the bio.
> >
> > Signed-off-by: Adam Manzananares <adam.manzanares@xxxxxxx>
>
> Jens, if you're okay with it, I can route this through
> libata/for-4.10, or this can be applied to block and libata tree can
> pull from it.

I'm fine with that, add my Reviewed-by and funnel it through the libata
tree.

--
Jens Axboe