On Wed, Dec 18, 2013 at 8:12 PM, Kent Overstreet <[email protected]> wrote:
> Now that we've got code for raid5/6 stripe awareness, bcache just needs
> to know about the stripes and when writing partial stripes is expensive
> - we probably don't want to enable this optimization for raid1 or 10,
> even though they have stripes. So add a flag to queue_limits.
>
> Signed-off-by: Kent Overstreet <[email protected]>
> ---
> This is in my pile of bcache stuff queued up for 3.14 - if no one objects it'll
> be in my bcache pull request:
>
> drivers/md/bcache/super.c | 6 ++++++
> drivers/md/raid5.c | 1 +
> include/linux/blkdev.h | 1 +
> 3 files changed, 8 insertions(+)
Hi Kent,
> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> index 02cb6f0ea7..0375654adb 100644
> --- a/include/linux/blkdev.h
> +++ b/include/linux/blkdev.h
> @@ -291,6 +291,7 @@ struct queue_limits {
> unsigned char discard_misaligned;
> unsigned char cluster;
> unsigned char discard_zeroes_data;
> + unsigned char raid_partial_stripes_expensive;
> };
>
> struct request_queue {
If you add a new member to queue_limits you need to update
blk_stack_limits() so that it propagates as you stack devices.
You probably also want to update blk_set_default_limits.
Mike
On Mon, Jan 06, 2014 at 09:04:25PM -0500, Mike Snitzer wrote:
> On Wed, Dec 18, 2013 at 8:12 PM, Kent Overstreet <[email protected]> wrote:
> > Now that we've got code for raid5/6 stripe awareness, bcache just needs
> > to know about the stripes and when writing partial stripes is expensive
> > - we probably don't want to enable this optimization for raid1 or 10,
> > even though they have stripes. So add a flag to queue_limits.
> >
> > Signed-off-by: Kent Overstreet <[email protected]>
> > ---
> > This is in my pile of bcache stuff queued up for 3.14 - if no one objects it'll
> > be in my bcache pull request:
> >
> > drivers/md/bcache/super.c | 6 ++++++
> > drivers/md/raid5.c | 1 +
> > include/linux/blkdev.h | 1 +
> > 3 files changed, 8 insertions(+)
>
> Hi Kent,
>
> > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> > index 02cb6f0ea7..0375654adb 100644
> > --- a/include/linux/blkdev.h
> > +++ b/include/linux/blkdev.h
> > @@ -291,6 +291,7 @@ struct queue_limits {
> > unsigned char discard_misaligned;
> > unsigned char cluster;
> > unsigned char discard_zeroes_data;
> > + unsigned char raid_partial_stripes_expensive;
> > };
> >
> > struct request_queue {
>
> If you add a new member to queue_limits you need to update
> blk_stack_limits() so that it propagates as you stack devices.
Thanks, going to send Jens a new pull after he does some merging so I'll include
that in the updated version.