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

[Hawkins Jiawei]

On 2023/6/1 21:43, Eugenio Perez Martin wrote:
> 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".

Hi Eugenio,

I sent the v3 patch before seeing this email:(.

I refactor the commit message to
"To support restoring offloads state in vdpa, need to expose
the function virtio_net_supported_guest_offloads().
QEMU uses this function to get the guest supported offloads
and no needs to send the corresponding CVQ command if guest
enables all supported features." in v3 patch.

Do you think there is still some refactoring needed here?

Thanks!


>
> 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
>>>
>>
>