On Mon, 1 Dec 2014 13:46:45 +0200 "Michael S. Tsirkin" <mst@xxxxxxxxxx> 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@xxxxxxxxxx> 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 :) > > > We should make sure that e.g. s390 only takes minor > > hit due to all that swapping that is needed for standard-compliant > > devices. Caching the value might certainly help in some paths. > > Well, this is queued in linux-next for 3.19, so > now's the time to do it :) So much to do, so little time... I'm still feeling a bit uncomfortable with some of the changes (virtio-scsi etc.) as I have not been able to test them yet (as there's no converted qemu for these yet). The virtio-net and virtio-blk changes seem sane, though, and virtio-ccw should be fine as well. OTOH, it's not like we're introducing new external interfaces, so later rework should be fine. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
