>>On Wednesday 10 February 2010, Xin Xiaohui wrote: > >The idea is simple, just to pin the guest VM user space and then > >let host NIC driver has the chance to directly DMA to it. > >The patches are based on vhost-net backend driver. We add a device > >which provides proto_ops as sendmsg/recvmsg to vhost-net to > >send/recv directly to/from the NIC driver. KVM guest who use the > >vhost-net backend may bind any ethX interface in the host side to > >get copyless data transfer thru guest virtio-net frontend. >> >> We provide multiple submits and asynchronous notifiicaton to > >vhost-net too. >This does a lot of things that I had planned for macvtap. It's >great to hear that you have made this much progress. > >However, I'd hope that we could combine this with the macvtap driver, >which would give us zero-copy transfer capability both with and >without vhost, as well as (tx at least) when using multiple guests >on a macvlan setup. You mean the zero-copy can work with macvtap driver without vhost. May you give me some detailed info about your macvtap driver and the relationship between vhost and macvtap to make me have a clear picture then? >For transmit, it should be fairly straightforward to hook up >your zero-copy method and the vhost-net interface into the >macvtap driver. > >You have simplified the receiv path significantly by assuming >that the entire netdev can receive into a single guest, right? Yes. >I'm assuming that the idea is to allow VMDq adapters to simply >show up as separate adapters and have the driver handle this >in a hardware specific way. Does the VMDq driver do so now? >My plan for this was to instead move support for VMDq into the >macvlan driver so we can transparently use VMDq on hardware where >available, including zero-copy receives, but fall back to software >operation on non-VMDq hardware. Arnd -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
