| Message ID | 20240617-stage-vdpa-vq-precreate-v1-21-8c0483f0ca2a@nvidia.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | vdpa/mlx5: Pre-create HW VQs to reduce LM downtime | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Not a local patch |
On Mon, Jun 17, 2024 at 5:09 PM Dragos Tatulea <dtatulea@nvidia.com> wrote: > > There are a few conditions under which the hardware VQs need a full > teardown and setup: > > - VQ size changed to something else than default value. Hardware VQ size > modification is not supported. > > - User turns off certain device features: mergeable buffers, checksum > virtio 1.0 compliance. In these cases, the TIR and RQT need to be > re-created. > > Add a needs_teardown configuration variable and set it when detecting > the above scenarios. On next DRIVER_OK, the resources will be torn down > first. > > Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com> > Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com> Acked-by: Eugenio Pérez <eperezma@redhat.com> > --- > drivers/vdpa/mlx5/net/mlx5_vnet.c | 15 +++++++++++++++ > drivers/vdpa/mlx5/net/mlx5_vnet.h | 1 + > 2 files changed, 16 insertions(+) > > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c > index b2836fd3d1dd..d80d6b47da61 100644 > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c > @@ -2390,6 +2390,7 @@ static void mlx5_vdpa_set_vq_num(struct vdpa_device *vdev, u16 idx, u32 num) > } > > mvq = &ndev->vqs[idx]; > + ndev->needs_teardown = num != mvq->num_ent; > mvq->num_ent = num; > } > > @@ -2800,6 +2801,7 @@ static int mlx5_vdpa_set_driver_features(struct vdpa_device *vdev, u64 features) > struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev); > struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev); > u64 old_features = mvdev->actual_features; > + u64 diff_features; > int err; > > print_features(mvdev, features, true); > @@ -2822,6 +2824,14 @@ static int mlx5_vdpa_set_driver_features(struct vdpa_device *vdev, u64 features) > } > } > > + /* When below features diverge from initial device features, VQs need a full teardown. */ > +#define NEEDS_TEARDOWN_MASK (BIT_ULL(VIRTIO_NET_F_MRG_RXBUF) | \ > + BIT_ULL(VIRTIO_NET_F_CSUM) | \ > + BIT_ULL(VIRTIO_F_VERSION_1)) > + > + diff_features = mvdev->mlx_features ^ mvdev->actual_features; > + ndev->needs_teardown = !!(diff_features & NEEDS_TEARDOWN_MASK); > + > update_cvq_info(mvdev); > return err; > } > @@ -3038,6 +3048,7 @@ static void teardown_vq_resources(struct mlx5_vdpa_net *ndev) > destroy_rqt(ndev); > teardown_virtqueues(ndev); > ndev->setup = false; > + ndev->needs_teardown = false; > } > > static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev) > @@ -3078,6 +3089,10 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status) > goto err_setup; > } > register_link_notifier(ndev); > + > + if (ndev->needs_teardown) > + teardown_vq_resources(ndev); > + > if (ndev->setup) { > err = resume_vqs(ndev); > if (err) { > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.h b/drivers/vdpa/mlx5/net/mlx5_vnet.h > index 2ada29767cc5..da7318f82d2a 100644 > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.h > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.h > @@ -56,6 +56,7 @@ struct mlx5_vdpa_net { > struct dentry *rx_dent; > struct dentry *rx_table_dent; > bool setup; > + bool needs_teardown; > u32 cur_num_vqs; > u32 rqt_size; > u16 default_queue_size; > > -- > 2.45.1 >
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c index b2836fd3d1dd..d80d6b47da61 100644 --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c @@ -2390,6 +2390,7 @@ static void mlx5_vdpa_set_vq_num(struct vdpa_device *vdev, u16 idx, u32 num) } mvq = &ndev->vqs[idx]; + ndev->needs_teardown = num != mvq->num_ent; mvq->num_ent = num; } @@ -2800,6 +2801,7 @@ static int mlx5_vdpa_set_driver_features(struct vdpa_device *vdev, u64 features) struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev); struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev); u64 old_features = mvdev->actual_features; + u64 diff_features; int err; print_features(mvdev, features, true); @@ -2822,6 +2824,14 @@ static int mlx5_vdpa_set_driver_features(struct vdpa_device *vdev, u64 features) } } + /* When below features diverge from initial device features, VQs need a full teardown. */ +#define NEEDS_TEARDOWN_MASK (BIT_ULL(VIRTIO_NET_F_MRG_RXBUF) | \ + BIT_ULL(VIRTIO_NET_F_CSUM) | \ + BIT_ULL(VIRTIO_F_VERSION_1)) + + diff_features = mvdev->mlx_features ^ mvdev->actual_features; + ndev->needs_teardown = !!(diff_features & NEEDS_TEARDOWN_MASK); + update_cvq_info(mvdev); return err; } @@ -3038,6 +3048,7 @@ static void teardown_vq_resources(struct mlx5_vdpa_net *ndev) destroy_rqt(ndev); teardown_virtqueues(ndev); ndev->setup = false; + ndev->needs_teardown = false; } static int setup_cvq_vring(struct mlx5_vdpa_dev *mvdev) @@ -3078,6 +3089,10 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status) goto err_setup; } register_link_notifier(ndev); + + if (ndev->needs_teardown) + teardown_vq_resources(ndev); + if (ndev->setup) { err = resume_vqs(ndev); if (err) { diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.h b/drivers/vdpa/mlx5/net/mlx5_vnet.h index 2ada29767cc5..da7318f82d2a 100644 --- a/drivers/vdpa/mlx5/net/mlx5_vnet.h +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.h @@ -56,6 +56,7 @@ struct mlx5_vdpa_net { struct dentry *rx_dent; struct dentry *rx_table_dent; bool setup; + bool needs_teardown; u32 cur_num_vqs; u32 rqt_size; u16 default_queue_size;