Re: [PATCH net v2] virtio-net: don't disable guest csum when disable LRO

[Tonghao Zhang <xiangxia.m.yue@gmail.com>]

On Tue, Sep 29, 2020 at 3:29 PM Willem de Bruijn
<willemdebruijn.kernel@gmail.com> wrote:
>
> On Tue, Sep 29, 2020 at 9:23 AM Michael S. Tsirkin <mst@redhat.com> wrote:
> >
> > On Tue, Sep 29, 2020 at 02:59:03PM +0800, Tonghao Zhang wrote:
> > > On Tue, Sep 29, 2020 at 2:23 PM Michael S. Tsirkin <mst@redhat.com> wrote:
> > > >
> > > > On Tue, Sep 29, 2020 at 09:58:06AM +0800, xiangxia.m.yue@gmail.com wrote:
> > > > > From: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> > > > >
> > > > > Open vSwitch and Linux bridge will disable LRO of the interface
> > > > > when this interface added to them. Now when disable the LRO, the
> > > > > virtio-net csum is disable too. That drops the forwarding performance.
> > > > >
> > > > > Fixes: a02e8964eaf9 ("virtio-net: ethtool configurable LRO")
> > > > > Cc: Michael S. Tsirkin <mst@redhat.com>
> > > > > Cc: Jason Wang <jasowang@redhat.com>
> > > > > Cc: Willem de Bruijn <willemb@google.com>
> > > > > Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> > > > > ---
> > > > > v2:
> > > > > * change the fix-tag
> > > > > ---
> > > > >  drivers/net/virtio_net.c | 8 +++++++-
> > > > >  1 file changed, 7 insertions(+), 1 deletion(-)
> > > > >
> > > > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> > > > > index 7145c83c6c8c..21b71148c532 100644
> > > > > --- a/drivers/net/virtio_net.c
> > > > > +++ b/drivers/net/virtio_net.c
> > > > > @@ -63,6 +63,11 @@ static const unsigned long guest_offloads[] = {
> > > > >       VIRTIO_NET_F_GUEST_CSUM
> > > > >  };
> > > > >
> > > > > +#define GUEST_OFFLOAD_LRO_MASK ((1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
> > > > > +                             (1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
> > > > > +                             (1ULL << VIRTIO_NET_F_GUEST_ECN)  | \
> > > > > +                             (1ULL << VIRTIO_NET_F_GUEST_UFO))
> > > > > +
> > > >
> > > > I think I'd rather we open-coded this, the macro is only
> > > > used in one place ...
> > > Yes, in this patch, it is used only in one place. But in next patch
> > > [1], we use it twice and that make the code look a bit nicer.
> > > Would we open-coded this in this patch ?
> > >
> > > [1] - http://patchwork.ozlabs.org/project/netdev/patch/20200928033915.82810-2-xiangxia.m.yue@gmail.com/
> >
> > OK then maybe keep this in a series like you did with v1.
>
> If this is a fix it has to target net, unlike the other patch.
Hi Willem, Michael
The first patch v2 is for -net, can we apply it?
and second patch will be sent for -net-next after discussion ? That is ok?

-- 
Best regards, Tonghao