On Sun, Mar 8, 2020 at 10:06 AM Michael S. Tsirkin <m...@redhat.com> wrote: > > On Fri, Mar 06, 2020 at 11:50:30AM +0200, Yuri Benditovich wrote: > > > > > > On Fri, Mar 6, 2020 at 11:27 AM Jason Wang <jasow...@redhat.com> wrote: > > > > > > On 2020/2/27 上午1:48, Yuri Benditovich wrote: > > > Support for VIRTIO_NET_F_RSS feature in QEMU for reference > > > purpose. Implements Toeplitz hash calculation for incoming > > > packets according to configuration provided by driver. > > > > > > This series requires previously submitted and accepted > > > patch to be applied: > > > https://lists.gnu.org/archive/html/qemu-devel/2020-01/msg06448.html > > > > > > Yuri Benditovich (3): > > > virtio-net: introduce RSS RX steering feature > > > virtio-net: implement RSS configuration command > > > virtio-net: implement RX RSS processing > > > > > > hw/net/trace-events | 3 + > > > hw/net/virtio-net.c | 234 > > +++++++++++++++++++-VIRTIO_NET_F_RSS > > > include/hw/virtio/virtio-net.h | 12 + > > > include/standard-headers/linux/virtio_net.h | 37 +++- > > > 4 files changed, 273 insertions(+), 13 deletions(-) > > > > > > > One question before the reviewing. > > > > Do we need to deal with migration (which I think yes)? > > > > > > I think we don't (yet) as this is a reference implementation and the main > > goal > > is to provide the functional reference for hardware solution. > > > That's fine, but then we must block migration, and add appropriate code > comments. Just silently losing data isn't a good idea.
Note that there is no data lost, just the configuration of RSS is not migrating. So, qemu just will not redirect the data to different queues after migration. I would add the migration prevention in the next series with implementation of hash delivery to prevent different packet sizes in driver and qemu. > > > I agree with the general direction that for complete support of RSS and hash > > delivery the best way is to do that in kernel using bpf. > > For that, IMO, the bpf should be a part of the kernel (it uses skb fields) > > and > > the tap should receive just RSS parameters for it. > > At this stage we definitely will need to add migration support and > > propagation > > of RSS parameters. > > > > > > > > Thanks > > > > >
