Re: [PATCH v2 4/6] virtio-net: expose virtio_net_supported_guest_offloads()

From: Eugenio Perez Martin <eperezma@redhat.com>
To: Hawkins Jiawei <yin31149@gmail.com>
Cc: jasowang@redhat.com, mst@redhat.com, qemu-devel@nongnu.org
Subject: Re: [PATCH v2 4/6] virtio-net: expose virtio_net_supported_guest_offloads()
Date: Thu, 1 Jun 2023 15:43:38 +0200	[thread overview]
Message-ID: <CAJaqyWewHKZebftQc6HrhDQEV5cTWiJUkVL4NgzOVqoGdP+6Sw@mail.gmail.com> (raw)
In-Reply-To: <CAKrof1OyEL5RGTWgHjgfMSkMC-afiWW8VAF5qirCy3juErWSqA@mail.gmail.com>

On Thu, Jun 1, 2023 at 11:05 AM Hawkins Jiawei <yin31149@gmail.com> wrote:
>
> On Thu, 1 Jun 2023 at 16:48, Hawkins Jiawei <yin31149@gmail.com> wrote:
> >
> > To support restoring offloads state in vdpa, need to expose
> > the function virtio_net_supported_guest_offloads(), then vdpa
> > uses this function to get the guest supported offloads.
>
> Here it should be changed to "then QEMU uses this function
> to get the guest supported offloads.". I will correct the commit
> message in the v3 patch.
>

Maybe "to get the device supported offloads allow qemu to know the
defaults, so it can skip the control message sending if they match
with the driver's configuration"?

We can also add "This will be the default at guest's startup, these
values can mismatch only at live migration".

What do you think?

Thanks!

> Thanks!
>
> >
> > Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
> > ---
> >  hw/net/virtio-net.c            | 2 +-
> >  include/hw/virtio/virtio-net.h | 1 +
> >  2 files changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> > index 7b27dad6c4..7e8897a8bc 100644
> > --- a/hw/net/virtio-net.c
> > +++ b/hw/net/virtio-net.c
> > @@ -874,7 +874,7 @@ static uint64_t virtio_net_guest_offloads_by_features(uint32_t features)
> >      return guest_offloads_mask & features;
> >  }
> >
> > -static inline uint64_t virtio_net_supported_guest_offloads(const VirtIONet *n)
> > +uint64_t virtio_net_supported_guest_offloads(const VirtIONet *n)
> >  {
> >      VirtIODevice *vdev = VIRTIO_DEVICE(n);
> >      return virtio_net_guest_offloads_by_features(vdev->guest_features);
> > diff --git a/include/hw/virtio/virtio-net.h b/include/hw/virtio/virtio-net.h
> > index ef234ffe7e..5f5dcb4572 100644
> > --- a/include/hw/virtio/virtio-net.h
> > +++ b/include/hw/virtio/virtio-net.h
> > @@ -227,5 +227,6 @@ size_t virtio_net_handle_ctrl_iov(VirtIODevice *vdev,
> >                                    unsigned out_num);
> >  void virtio_net_set_netclient_name(VirtIONet *n, const char *name,
> >                                     const char *type);
> > +uint64_t virtio_net_supported_guest_offloads(const VirtIONet *n);
> >
> >  #endif
> > --
> > 2.25.1
> >
>