Si-Wei Liu
2023-Jul-04 00:26 UTC
[PATCH] mlx5_vdpa: offer VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK
On 7/3/2023 8:46 AM, Michael S. Tsirkin wrote:> On Mon, Jul 03, 2023 at 04:25:14PM +0200, Eugenio P?rez wrote: >> Offer this backend feature as mlx5 is compatible with it. It allows it >> to do live migration with CVQ, dynamically switching between passthrough >> and shadow virtqueue. >> >> Signed-off-by: Eugenio P?rez <eperezma at redhat.com> > Same comment.to which? -Siwei> >> --- >> drivers/vdpa/mlx5/net/mlx5_vnet.c | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c >> index 9138ef2fb2c8..5f309a16b9dc 100644 >> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c >> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c >> @@ -7,6 +7,7 @@ >> #include <uapi/linux/virtio_net.h> >> #include <uapi/linux/virtio_ids.h> >> #include <uapi/linux/vdpa.h> >> +#include <uapi/linux/vhost_types.h> >> #include <linux/virtio_config.h> >> #include <linux/auxiliary_bus.h> >> #include <linux/mlx5/cq.h> >> @@ -2499,6 +2500,11 @@ static void unregister_link_notifier(struct mlx5_vdpa_net *ndev) >> flush_workqueue(ndev->mvdev.wq); >> } >> >> +static u64 mlx5_vdpa_get_backend_features(const struct vdpa_device *vdpa) >> +{ >> + return BIT_ULL(VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK); >> +} >> + >> static int mlx5_vdpa_set_driver_features(struct vdpa_device *vdev, u64 features) >> { >> struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev); >> @@ -3140,6 +3146,7 @@ static const struct vdpa_config_ops mlx5_vdpa_ops = { >> .get_vq_align = mlx5_vdpa_get_vq_align, >> .get_vq_group = mlx5_vdpa_get_vq_group, >> .get_device_features = mlx5_vdpa_get_device_features, >> + .get_backend_features = mlx5_vdpa_get_backend_features, >> .set_driver_features = mlx5_vdpa_set_driver_features, >> .get_driver_features = mlx5_vdpa_get_driver_features, >> .set_config_cb = mlx5_vdpa_set_config_cb, >> -- >> 2.39.3
Michael S. Tsirkin
2023-Jul-04 10:16 UTC
[PATCH] mlx5_vdpa: offer VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK
On Mon, Jul 03, 2023 at 05:26:02PM -0700, Si-Wei Liu wrote:> > > On 7/3/2023 8:46 AM, Michael S. Tsirkin wrote: > > On Mon, Jul 03, 2023 at 04:25:14PM +0200, Eugenio P?rez wrote: > > > Offer this backend feature as mlx5 is compatible with it. It allows it > > > to do live migration with CVQ, dynamically switching between passthrough > > > and shadow virtqueue. > > > > > > Signed-off-by: Eugenio P?rez <eperezma at redhat.com> > > Same comment. > to which? > > -SiweiVHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK is too narrow a use-case to commit to it as a kernel/userspace ABI: what if one wants to start rings in some other specific order? As was discussed on list, a better promise is not to access ring until the 1st kick. vdpa can then do a kick when it wants the device to start accessing rings.> > > > > --- > > > drivers/vdpa/mlx5/net/mlx5_vnet.c | 7 +++++++ > > > 1 file changed, 7 insertions(+) > > > > > > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > index 9138ef2fb2c8..5f309a16b9dc 100644 > > > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > @@ -7,6 +7,7 @@ > > > #include <uapi/linux/virtio_net.h> > > > #include <uapi/linux/virtio_ids.h> > > > #include <uapi/linux/vdpa.h> > > > +#include <uapi/linux/vhost_types.h> > > > #include <linux/virtio_config.h> > > > #include <linux/auxiliary_bus.h> > > > #include <linux/mlx5/cq.h> > > > @@ -2499,6 +2500,11 @@ static void unregister_link_notifier(struct mlx5_vdpa_net *ndev) > > > flush_workqueue(ndev->mvdev.wq); > > > } > > > +static u64 mlx5_vdpa_get_backend_features(const struct vdpa_device *vdpa) > > > +{ > > > + return BIT_ULL(VHOST_BACKEND_F_ENABLE_AFTER_DRIVER_OK); > > > +} > > > + > > > static int mlx5_vdpa_set_driver_features(struct vdpa_device *vdev, u64 features) > > > { > > > struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev); > > > @@ -3140,6 +3146,7 @@ static const struct vdpa_config_ops mlx5_vdpa_ops = { > > > .get_vq_align = mlx5_vdpa_get_vq_align, > > > .get_vq_group = mlx5_vdpa_get_vq_group, > > > .get_device_features = mlx5_vdpa_get_device_features, > > > + .get_backend_features = mlx5_vdpa_get_backend_features, > > > .set_driver_features = mlx5_vdpa_set_driver_features, > > > .get_driver_features = mlx5_vdpa_get_driver_features, > > > .set_config_cb = mlx5_vdpa_set_config_cb, > > > -- > > > 2.39.3