On 2023/5/30 0:19, Eugenio Perez Martin wrote:
> On Mon, May 29, 2023 at 3:18 PM Hawkins Jiawei <yin31...@gmail.com> wrote:
>>
>> This patch introduces vhost_vdpa_net_load_offloads() to
>> restore offloads state at device's startup.
>>
>> Signed-off-by: Hawkins Jiawei <yin31...@gmail.com>
>> ---
>> net/vhost-vdpa.c | 26 ++++++++++++++++++++++++++
>> 1 file changed, 26 insertions(+)
>>
>> diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
>> index 37cdc84562..682c749b19 100644
>> --- a/net/vhost-vdpa.c
>> +++ b/net/vhost-vdpa.c
>> @@ -680,6 +680,28 @@ static int vhost_vdpa_net_load_mq(VhostVDPAState *s,
>> return *s->status != VIRTIO_NET_OK;
>> }
>>
>> +static int vhost_vdpa_net_load_offloads(VhostVDPAState *s,
>> + const VirtIONet *n)
>> +{
>> + uint64_t features, offloads;
>> + ssize_t dev_written;
>> +
>> + features = n->parent_obj.guest_features;
>> + if (!(features & BIT_ULL(VIRTIO_NET_F_CTRL_GUEST_OFFLOADS))) {
>> + return 0;
>> + }
>> +
>
> Maybe we can avoid sending this CVQ command if the guest already uses
> the default values?
Hi Eugenio,
Thanks for the review. However, I'm curious why we don't need to send
this CVQ command if the guest is using the default values. Is it because
the device automatically applies these default offloads, when the
VIRTIO_NET_F_CTRL_GUEST_OFFLOADS feature is negotiated and QEMU doesn't
send the CVQ command?
Thanks!
>
> By default all features are enabled if I'm not wrong. I think the best
> way is to expose virtio_net_supported_guest_offloads or
> virtio_net_guest_offloads_by_features and then check if
> n->curr_guest_offloads is the same.
>
> We should do the same with vhost_vdpa_net_load_mq, but that is out of
> the scope of this series.
>
> Thanks!
>
>> + offloads = cpu_to_le64(n->curr_guest_offloads);
>> + dev_written = vhost_vdpa_net_load_cmd(s, VIRTIO_NET_CTRL_GUEST_OFFLOADS,
>> +
>> VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET,
>> + &offloads, sizeof(offloads));
>> + if (unlikely(dev_written < 0)) {
>> + return dev_written;
>> + }
>> +
>> + return *s->status != VIRTIO_NET_OK;
>> +}
>> +
>> static int vhost_vdpa_net_load(NetClientState *nc)
>> {
>> VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
>> @@ -702,6 +724,10 @@ static int vhost_vdpa_net_load(NetClientState *nc)
>> if (unlikely(r)) {
>> return r;
>> }
>> + r = vhost_vdpa_net_load_offloads(s, n);
>> + if (unlikely(r)) {
>> + return r;
>> + }
>>
>> return 0;
>> }
>> --
>> 2.25.1
>>
>
