Re: [PATCH v7 16/46] virtio_blk: v1.0 support

["Michael S. Tsirkin" <mst@redhat.com>]

On Mon, Dec 01, 2014 at 01:40:36PM +0100, Cornelia Huck wrote:
> On Mon, 1 Dec 2014 14:34:55 +0200
> "Michael S. Tsirkin" <mst@redhat.com> wrote:
> 
> > On Mon, Dec 01, 2014 at 01:02:58PM +0100, Cornelia Huck wrote:
> > > On Mon, 1 Dec 2014 13:46:45 +0200
> > > "Michael S. Tsirkin" <mst@redhat.com> wrote:
> > > 
> > > > On Mon, Dec 01, 2014 at 12:33:15PM +0100, Cornelia Huck wrote:
> > > > > On Mon, 1 Dec 2014 11:26:58 +0200
> > > > > "Michael S. Tsirkin" <mst@redhat.com> wrote:
> > > > > 
> > > > > > For some places on data path, it might be worth it
> > > > > > to cache the correct value e.g. as part of device
> > > > > > structure. This replaces a branch with a memory load,
> > > > > > so the gain would have to be measured, best done
> > > > > > separately?
> > > > > 
> > > > > I think we'll want to do some measuring once the basic structure is
> > > > > in place anyway.
> > > > 
> > > > What's meant by in place here?
> > > 
> > > That this patchset is ready :)
> > 
> > Also it's ready to the level where benchmarking is possible, right?  I
> > don't think you should wait until we finish polishing up commit
> > messages.
> 
> My point is that I haven't even found time yet to test this
> thouroughly :(

If my experience shows anything, it's unlikely we'll get appropriate
testing without code being upstream first.
That's why I pushed on with sparse tagging btw.
This way we can be reasonably sure we didn't miss some path.

-- 
MST