Re: [PATCH v3 4/5] vdpa: move vhost_vdpa_set_vring_ready to the caller

[Jason Wang]

On Tue, Aug 22, 2023 at 4:53 PM Eugenio Pérez <eperezma@redhat.com> wrote:
>
> Doing that way allows CVQ to be enabled before the dataplane vqs,
> restoring the state as MQ or MAC addresses properly in the case of a
> migration.
>
> The patch does it by defining a ->load NetClientInfo callback also for
> dataplane.  Ideally, this should be done by an independent patch, but
> the function is already static so it would only add an empty
> vhost_vdpa_net_data_load stub.
>
> Signed-off-by: Eugenio Pérez <eperezma@redhat.com>

Acked-by: Jason Wang <jasowang@redhat.com>

Thanks

> ---
> v3:
> * Fix subject typo
> * Expand patch message so it explains why
> ---
>  hw/virtio/vdpa-dev.c   |  3 +++
>  hw/virtio/vhost-vdpa.c |  3 ---
>  net/vhost-vdpa.c       | 57 +++++++++++++++++++++++++++++-------------
>  3 files changed, 42 insertions(+), 21 deletions(-)
>
> diff --git a/hw/virtio/vdpa-dev.c b/hw/virtio/vdpa-dev.c
> index 363b625243..f22d5d5bc0 100644
> --- a/hw/virtio/vdpa-dev.c
> +++ b/hw/virtio/vdpa-dev.c
> @@ -255,6 +255,9 @@ static int vhost_vdpa_device_start(VirtIODevice *vdev, 
> Error **errp)
>          error_setg_errno(errp, -ret, "Error starting vhost");
>          goto err_guest_notifiers;
>      }
> +    for (i = 0; i < s->dev.nvqs; ++i) {
> +        vhost_vdpa_set_vring_ready(&s->vdpa, i);
> +    }
>      s->started = true;
>
>      /*
> diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
> index 0d9975b5b5..8ca2e3800c 100644
> --- a/hw/virtio/vhost-vdpa.c
> +++ b/hw/virtio/vhost-vdpa.c
> @@ -1297,9 +1297,6 @@ static int vhost_vdpa_dev_start(struct vhost_dev *dev, 
> bool started)
>          if (unlikely(!ok)) {
>              return -1;
>          }
> -        for (int i = 0; i < dev->nvqs; ++i) {
> -            vhost_vdpa_set_vring_ready(v, dev->vq_index + i);
> -        }
>      } else {
>          vhost_vdpa_suspend(dev);
>          vhost_vdpa_svqs_stop(dev);
> diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
> index 9251351b4b..3bf60f9431 100644
> --- a/net/vhost-vdpa.c
> +++ b/net/vhost-vdpa.c
> @@ -371,6 +371,22 @@ static int vhost_vdpa_net_data_start(NetClientState *nc)
>      return 0;
>  }
>
> +static int vhost_vdpa_net_data_load(NetClientState *nc)
> +{
> +    VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
> +    struct vhost_vdpa *v = &s->vhost_vdpa;
> +    bool has_cvq = v->dev->vq_index_end % 2;
> +
> +    if (has_cvq) {
> +        return 0;
> +    }
> +
> +    for (int i = 0; i < v->dev->nvqs; ++i) {
> +        vhost_vdpa_set_vring_ready(v, i + v->dev->vq_index);
> +    }
> +    return 0;
> +}
> +
>  static void vhost_vdpa_net_client_stop(NetClientState *nc)
>  {
>      VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
> @@ -393,6 +409,7 @@ static NetClientInfo net_vhost_vdpa_info = {
>          .size = sizeof(VhostVDPAState),
>          .receive = vhost_vdpa_receive,
>          .start = vhost_vdpa_net_data_start,
> +        .load = vhost_vdpa_net_data_load,
>          .stop = vhost_vdpa_net_client_stop,
>          .cleanup = vhost_vdpa_cleanup,
>          .has_vnet_hdr = vhost_vdpa_has_vnet_hdr,
> @@ -974,26 +991,30 @@ static int vhost_vdpa_net_cvq_load(NetClientState *nc)
>
>      assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
>
> -    if (!v->shadow_vqs_enabled) {
> -        return 0;
> -    }
> +    vhost_vdpa_set_vring_ready(v, v->dev->vq_index);
>
> -    n = VIRTIO_NET(v->dev->vdev);
> -    r = vhost_vdpa_net_load_mac(s, n);
> -    if (unlikely(r < 0)) {
> -        return r;
> -    }
> -    r = vhost_vdpa_net_load_mq(s, n);
> -    if (unlikely(r)) {
> -        return r;
> -    }
> -    r = vhost_vdpa_net_load_offloads(s, n);
> -    if (unlikely(r)) {
> -        return r;
> +    if (v->shadow_vqs_enabled) {
> +        n = VIRTIO_NET(v->dev->vdev);
> +        r = vhost_vdpa_net_load_mac(s, n);
> +        if (unlikely(r < 0)) {
> +            return r;
> +        }
> +        r = vhost_vdpa_net_load_mq(s, n);
> +        if (unlikely(r)) {
> +            return r;
> +        }
> +        r = vhost_vdpa_net_load_offloads(s, n);
> +        if (unlikely(r)) {
> +            return r;
> +        }
> +        r = vhost_vdpa_net_load_rx(s, n);
> +        if (unlikely(r)) {
> +            return r;
> +        }
>      }
> -    r = vhost_vdpa_net_load_rx(s, n);
> -    if (unlikely(r)) {
> -        return r;
> +
> +    for (int i = 0; i < v->dev->vq_index; ++i) {
> +        vhost_vdpa_set_vring_ready(v, i);
>      }
>
>      return 0;
> --
> 2.39.3
>