lkml.org 
[lkml]   [2008]   [Aug]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: request->ioprio
Date

On Aug 6, 2008, at 2:32 AM, Fernando Luis Vázquez Cao wrote:

> (CCing LKML)
>
> Hi Jens, Rusty,
>
> Trying to implement i/o tracking all the way up to the page cache (so
> that cfq and the future cgroup-based I/O controllers can schedule
> buffered I/O properly) I noticed that struct request's ioprio is
> initialized but never used for I/O scheduling purposes. Indeed there
> seems to be one single user of this member: virtio_blk. Virtio uses
> struct request's ioprio in the request() function of the virtio block
> driver, which just copies the ioprio value to the output header of
> virtblk_req.
>
> Is this the intended use of struct request's ioprio? Is it OK for
> device
> drivers to use it? If the answer two the previous to questions is no I
> would like to send some clean-up patches.

Naveen Gupta sent a priority-based anticipatory IO scheduler patchset
earlier which uses request->ioprio and the struct request seems to be
the logical place to keep the ioprio. So, please don't cleanup the
ioprio from there.

Thanks,
Divyesh

>
> - Fernando
>



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2008-08-06 19:27    [W:0.055 / U:0.696 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site