On Thu, Nov 10, 2022 at 6:40 AM Jason Wang <jasowang@xxxxxxxxxx> wrote:
>
>
> 在 2022/11/9 01:07, Eugenio Pérez 写道:
> > The next patches will start control SVQ if possible. However, we don't
> > know if that will be possible at qemu boot anymore.
>
>
> If I was not wrong, there's no device specific feature that is checked
> in the function. So it should be general enough to be used by devices
> other than net. Then I don't see any advantage of doing this.
>
Because vhost_vdpa_init_svq is called at qemu boot, failing if it is
not possible to shadow the Virtqueue.
Now the CVQ will be shadowed if possible, so we need to check this at
device start, not at initialization. To store this information at boot
time is not valid anymore, because v->shadow_vqs_enabled is not valid
at this time anymore.
Thanks!
> Thanks
>
>
> >
> > Since the moved checks will be already evaluated at net/ to know if it
> > is ok to shadow CVQ, move them.
> >
> > Signed-off-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
> > ---
> > hw/virtio/vhost-vdpa.c | 33 ++-------------------------------
> > net/vhost-vdpa.c | 3 ++-
> > 2 files changed, 4 insertions(+), 32 deletions(-)
> >
> > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
> > index 3df2775760..146f0dcb40 100644
> > --- a/hw/virtio/vhost-vdpa.c
> > +++ b/hw/virtio/vhost-vdpa.c
> > @@ -402,29 +402,9 @@ static int vhost_vdpa_get_dev_features(struct vhost_dev *dev,
> > return ret;
> > }
> >
> > -static int vhost_vdpa_init_svq(struct vhost_dev *hdev, struct vhost_vdpa *v,
> > - Error **errp)
> > +static void vhost_vdpa_init_svq(struct vhost_dev *hdev, struct vhost_vdpa *v)
> > {
> > g_autoptr(GPtrArray) shadow_vqs = NULL;
> > - uint64_t dev_features, svq_features;
> > - int r;
> > - bool ok;
> > -
> > - if (!v->shadow_vqs_enabled) {
> > - return 0;
> > - }
> > -
> > - r = vhost_vdpa_get_dev_features(hdev, &dev_features);
> > - if (r != 0) {
> > - error_setg_errno(errp, -r, "Can't get vdpa device features");
> > - return r;
> > - }
> > -
> > - svq_features = dev_features;
> > - ok = vhost_svq_valid_features(svq_features, errp);
> > - if (unlikely(!ok)) {
> > - return -1;
> > - }
> >
> > shadow_vqs = g_ptr_array_new_full(hdev->nvqs, vhost_svq_free);
> > for (unsigned n = 0; n < hdev->nvqs; ++n) {
> > @@ -436,7 +416,6 @@ static int vhost_vdpa_init_svq(struct vhost_dev *hdev, struct vhost_vdpa *v,
> > }
> >
> > v->shadow_vqs = g_steal_pointer(&shadow_vqs);
> > - return 0;
> > }
> >
> > static int vhost_vdpa_init(struct vhost_dev *dev, void *opaque, Error **errp)
> > @@ -461,11 +440,7 @@ static int vhost_vdpa_init(struct vhost_dev *dev, void *opaque, Error **errp)
> > dev->opaque = opaque ;
> > v->listener = vhost_vdpa_memory_listener;
> > v->msg_type = VHOST_IOTLB_MSG_V2;
> > - ret = vhost_vdpa_init_svq(dev, v, errp);
> > - if (ret) {
> > - goto err;
> > - }
> > -
> > + vhost_vdpa_init_svq(dev, v);
> > vhost_vdpa_get_iova_range(v);
> >
> > if (!vhost_vdpa_first_dev(dev)) {
> > @@ -476,10 +451,6 @@ static int vhost_vdpa_init(struct vhost_dev *dev, void *opaque, Error **errp)
> > VIRTIO_CONFIG_S_DRIVER);
> >
> > return 0;
> > -
> > -err:
> > - ram_block_discard_disable(false);
> > - return ret;
> > }
> >
> > static void vhost_vdpa_host_notifier_uninit(struct vhost_dev *dev,
> > diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
> > index d3b1de481b..fb35b17ab4 100644
> > --- a/net/vhost-vdpa.c
> > +++ b/net/vhost-vdpa.c
> > @@ -117,9 +117,10 @@ static bool vhost_vdpa_net_valid_svq_features(uint64_t features, Error **errp)
> > if (invalid_dev_features) {
> > error_setg(errp, "vdpa svq does not work with features 0x%" PRIx64,
> > invalid_dev_features);
> > + return false;
> > }
> >
> > - return !invalid_dev_features;
> > + return vhost_svq_valid_features(features, errp);
> > }
> >
> > static int vhost_vdpa_net_check_device_id(struct vhost_net *net)
>
