| Message ID | 20230208094253.702672-5-eperezma@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Dynamycally switch to vhost shadow virtqueues at vdpa net migration | expand |
在 2023/2/8 17:42, Eugenio Pérez 写道: > The function vhost.c:vhost_dev_stop calls vhost operation > vhost_dev_start(false). In the case of vdpa it totally reset and wipes > the device, making the fetching of the vring base (virtqueue state) totally > useless. > > The kernel backend does not use vhost_dev_start vhost op callback, but > vhost-user do. A patch to make vhost_user_dev_start more similar to vdpa > is desirable, but it can be added on top. > > Signed-off-by: Eugenio Pérez <eperezma@redhat.com> > --- > include/hw/virtio/vhost-backend.h | 4 ++++ > hw/virtio/vhost-vdpa.c | 22 ++++++++++++++++------ > hw/virtio/vhost.c | 3 +++ > 3 files changed, 23 insertions(+), 6 deletions(-) > > diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h > index c5ab49051e..ec3fbae58d 100644 > --- a/include/hw/virtio/vhost-backend.h > +++ b/include/hw/virtio/vhost-backend.h > @@ -130,6 +130,9 @@ typedef bool (*vhost_force_iommu_op)(struct vhost_dev *dev); > > typedef int (*vhost_set_config_call_op)(struct vhost_dev *dev, > int fd); > + > +typedef void (*vhost_reset_status_op)(struct vhost_dev *dev); > + > typedef struct VhostOps { > VhostBackendType backend_type; > vhost_backend_init vhost_backend_init; > @@ -177,6 +180,7 @@ typedef struct VhostOps { > vhost_get_device_id_op vhost_get_device_id; > vhost_force_iommu_op vhost_force_iommu; > vhost_set_config_call_op vhost_set_config_call; > + vhost_reset_status_op vhost_reset_status; > } VhostOps; > > int vhost_backend_update_device_iotlb(struct vhost_dev *dev, > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c > index cbbe92ffe8..26e38a6aab 100644 > --- a/hw/virtio/vhost-vdpa.c > +++ b/hw/virtio/vhost-vdpa.c > @@ -1152,14 +1152,23 @@ static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started) > if (started) { > memory_listener_register(&v->listener, &address_space_memory); > return vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK); > - } else { > - vhost_vdpa_reset_device(dev); > - vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE | > - VIRTIO_CONFIG_S_DRIVER); > - memory_listener_unregister(&v->listener); > + } > > - return 0; > + return 0; > +} > + > +static void vhost_vdpa_reset_status(struct vhost_dev *dev) > +{ > + struct vhost_vdpa *v = dev->opaque; > + > + if (dev->vq_index + dev->nvqs != dev->vq_index_end) { > + return; > } > + > + vhost_vdpa_reset_device(dev); > + vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE | > + VIRTIO_CONFIG_S_DRIVER); > + memory_listener_unregister(&v->listener); > } > > static int vhost_vdpa_set_log_base(struct vhost_dev *dev, uint64_t base, > @@ -1346,4 +1355,5 @@ const VhostOps vdpa_ops = { > .vhost_vq_get_addr = vhost_vdpa_vq_get_addr, > .vhost_force_iommu = vhost_vdpa_force_iommu, > .vhost_set_config_call = vhost_vdpa_set_config_call, > + .vhost_reset_status = vhost_vdpa_reset_status, > }; > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c > index eb8c4c378c..a266396576 100644 > --- a/hw/virtio/vhost.c > +++ b/hw/virtio/vhost.c > @@ -2049,6 +2049,9 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) > hdev->vqs + i, > hdev->vq_index + i); > } > + if (hdev->vhost_ops->vhost_reset_status) { > + hdev->vhost_ops->vhost_reset_status(hdev); > + } This looks racy, if we don't suspend/reset the device, device can move last_avail_idx even after get_vring_base()? Instead of doing things like this, should we fallback to virtio_queue_restore_last_avail_idx() in this case? Thanks > > if (vhost_dev_has_iommu(hdev)) { > if (hdev->vhost_ops->vhost_set_iotlb_callback) {
On Tue, Feb 21, 2023 at 6:36 AM Jason Wang <jasowang@redhat.com> wrote: > > > 在 2023/2/8 17:42, Eugenio Pérez 写道: > > The function vhost.c:vhost_dev_stop calls vhost operation > > vhost_dev_start(false). In the case of vdpa it totally reset and wipes > > the device, making the fetching of the vring base (virtqueue state) totally > > useless. > > > > The kernel backend does not use vhost_dev_start vhost op callback, but > > vhost-user do. A patch to make vhost_user_dev_start more similar to vdpa > > is desirable, but it can be added on top. > > > > Signed-off-by: Eugenio Pérez <eperezma@redhat.com> > > --- > > include/hw/virtio/vhost-backend.h | 4 ++++ > > hw/virtio/vhost-vdpa.c | 22 ++++++++++++++++------ > > hw/virtio/vhost.c | 3 +++ > > 3 files changed, 23 insertions(+), 6 deletions(-) > > > > diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h > > index c5ab49051e..ec3fbae58d 100644 > > --- a/include/hw/virtio/vhost-backend.h > > +++ b/include/hw/virtio/vhost-backend.h > > @@ -130,6 +130,9 @@ typedef bool (*vhost_force_iommu_op)(struct vhost_dev *dev); > > > > typedef int (*vhost_set_config_call_op)(struct vhost_dev *dev, > > int fd); > > + > > +typedef void (*vhost_reset_status_op)(struct vhost_dev *dev); > > + > > typedef struct VhostOps { > > VhostBackendType backend_type; > > vhost_backend_init vhost_backend_init; > > @@ -177,6 +180,7 @@ typedef struct VhostOps { > > vhost_get_device_id_op vhost_get_device_id; > > vhost_force_iommu_op vhost_force_iommu; > > vhost_set_config_call_op vhost_set_config_call; > > + vhost_reset_status_op vhost_reset_status; > > } VhostOps; > > > > int vhost_backend_update_device_iotlb(struct vhost_dev *dev, > > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c > > index cbbe92ffe8..26e38a6aab 100644 > > --- a/hw/virtio/vhost-vdpa.c > > +++ b/hw/virtio/vhost-vdpa.c > > @@ -1152,14 +1152,23 @@ static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started) > > if (started) { > > memory_listener_register(&v->listener, &address_space_memory); > > return vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK); > > - } else { > > - vhost_vdpa_reset_device(dev); > > - vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE | > > - VIRTIO_CONFIG_S_DRIVER); > > - memory_listener_unregister(&v->listener); > > + } > > > > - return 0; > > + return 0; > > +} > > + > > +static void vhost_vdpa_reset_status(struct vhost_dev *dev) > > +{ > > + struct vhost_vdpa *v = dev->opaque; > > + > > + if (dev->vq_index + dev->nvqs != dev->vq_index_end) { > > + return; > > } > > + > > + vhost_vdpa_reset_device(dev); > > + vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE | > > + VIRTIO_CONFIG_S_DRIVER); > > + memory_listener_unregister(&v->listener); > > } > > > > static int vhost_vdpa_set_log_base(struct vhost_dev *dev, uint64_t base, > > @@ -1346,4 +1355,5 @@ const VhostOps vdpa_ops = { > > .vhost_vq_get_addr = vhost_vdpa_vq_get_addr, > > .vhost_force_iommu = vhost_vdpa_force_iommu, > > .vhost_set_config_call = vhost_vdpa_set_config_call, > > + .vhost_reset_status = vhost_vdpa_reset_status, > > }; > > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c > > index eb8c4c378c..a266396576 100644 > > --- a/hw/virtio/vhost.c > > +++ b/hw/virtio/vhost.c > > @@ -2049,6 +2049,9 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) > > hdev->vqs + i, > > hdev->vq_index + i); > > } > > + if (hdev->vhost_ops->vhost_reset_status) { > > + hdev->vhost_ops->vhost_reset_status(hdev); > > + } > > > This looks racy, if we don't suspend/reset the device, device can move > last_avail_idx even after get_vring_base()? > > Instead of doing things like this, should we fallback to > virtio_queue_restore_last_avail_idx() in this case? > Right, we can track if the device is suspended / SVQ and then return an error in vring_get_base if it is not. Would that work? Thanks! > Thanks > > > > > > if (vhost_dev_has_iommu(hdev)) { > > if (hdev->vhost_ops->vhost_set_iotlb_callback) { >
On Tue, Feb 21, 2023 at 3:08 PM Eugenio Perez Martin <eperezma@redhat.com> wrote: > > On Tue, Feb 21, 2023 at 6:36 AM Jason Wang <jasowang@redhat.com> wrote: > > > > > > 在 2023/2/8 17:42, Eugenio Pérez 写道: > > > The function vhost.c:vhost_dev_stop calls vhost operation > > > vhost_dev_start(false). In the case of vdpa it totally reset and wipes > > > the device, making the fetching of the vring base (virtqueue state) totally > > > useless. > > > > > > The kernel backend does not use vhost_dev_start vhost op callback, but > > > vhost-user do. A patch to make vhost_user_dev_start more similar to vdpa > > > is desirable, but it can be added on top. > > > > > > Signed-off-by: Eugenio Pérez <eperezma@redhat.com> > > > --- > > > include/hw/virtio/vhost-backend.h | 4 ++++ > > > hw/virtio/vhost-vdpa.c | 22 ++++++++++++++++------ > > > hw/virtio/vhost.c | 3 +++ > > > 3 files changed, 23 insertions(+), 6 deletions(-) > > > > > > diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h > > > index c5ab49051e..ec3fbae58d 100644 > > > --- a/include/hw/virtio/vhost-backend.h > > > +++ b/include/hw/virtio/vhost-backend.h > > > @@ -130,6 +130,9 @@ typedef bool (*vhost_force_iommu_op)(struct vhost_dev *dev); > > > > > > typedef int (*vhost_set_config_call_op)(struct vhost_dev *dev, > > > int fd); > > > + > > > +typedef void (*vhost_reset_status_op)(struct vhost_dev *dev); > > > + > > > typedef struct VhostOps { > > > VhostBackendType backend_type; > > > vhost_backend_init vhost_backend_init; > > > @@ -177,6 +180,7 @@ typedef struct VhostOps { > > > vhost_get_device_id_op vhost_get_device_id; > > > vhost_force_iommu_op vhost_force_iommu; > > > vhost_set_config_call_op vhost_set_config_call; > > > + vhost_reset_status_op vhost_reset_status; > > > } VhostOps; > > > > > > int vhost_backend_update_device_iotlb(struct vhost_dev *dev, > > > diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c > > > index cbbe92ffe8..26e38a6aab 100644 > > > --- a/hw/virtio/vhost-vdpa.c > > > +++ b/hw/virtio/vhost-vdpa.c > > > @@ -1152,14 +1152,23 @@ static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started) > > > if (started) { > > > memory_listener_register(&v->listener, &address_space_memory); > > > return vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK); > > > - } else { > > > - vhost_vdpa_reset_device(dev); > > > - vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE | > > > - VIRTIO_CONFIG_S_DRIVER); > > > - memory_listener_unregister(&v->listener); > > > + } > > > > > > - return 0; > > > + return 0; > > > +} > > > + > > > +static void vhost_vdpa_reset_status(struct vhost_dev *dev) > > > +{ > > > + struct vhost_vdpa *v = dev->opaque; > > > + > > > + if (dev->vq_index + dev->nvqs != dev->vq_index_end) { > > > + return; > > > } > > > + > > > + vhost_vdpa_reset_device(dev); > > > + vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE | > > > + VIRTIO_CONFIG_S_DRIVER); > > > + memory_listener_unregister(&v->listener); > > > } > > > > > > static int vhost_vdpa_set_log_base(struct vhost_dev *dev, uint64_t base, > > > @@ -1346,4 +1355,5 @@ const VhostOps vdpa_ops = { > > > .vhost_vq_get_addr = vhost_vdpa_vq_get_addr, > > > .vhost_force_iommu = vhost_vdpa_force_iommu, > > > .vhost_set_config_call = vhost_vdpa_set_config_call, > > > + .vhost_reset_status = vhost_vdpa_reset_status, > > > }; > > > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c > > > index eb8c4c378c..a266396576 100644 > > > --- a/hw/virtio/vhost.c > > > +++ b/hw/virtio/vhost.c > > > @@ -2049,6 +2049,9 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) > > > hdev->vqs + i, > > > hdev->vq_index + i); > > > } > > > + if (hdev->vhost_ops->vhost_reset_status) { > > > + hdev->vhost_ops->vhost_reset_status(hdev); > > > + } > > > > > > This looks racy, if we don't suspend/reset the device, device can move > > last_avail_idx even after get_vring_base()? > > > > Instead of doing things like this, should we fallback to > > virtio_queue_restore_last_avail_idx() in this case? > > > > Right, we can track if the device is suspended / SVQ and then return > an error in vring_get_base if it is not. Would that work? When we don't support suspend, yes. Thanks > > Thanks! > > > Thanks > > > > > > > > > > if (vhost_dev_has_iommu(hdev)) { > > > if (hdev->vhost_ops->vhost_set_iotlb_callback) { > > > >
diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h index c5ab49051e..ec3fbae58d 100644 --- a/include/hw/virtio/vhost-backend.h +++ b/include/hw/virtio/vhost-backend.h @@ -130,6 +130,9 @@ typedef bool (*vhost_force_iommu_op)(struct vhost_dev *dev); typedef int (*vhost_set_config_call_op)(struct vhost_dev *dev, int fd); + +typedef void (*vhost_reset_status_op)(struct vhost_dev *dev); + typedef struct VhostOps { VhostBackendType backend_type; vhost_backend_init vhost_backend_init; @@ -177,6 +180,7 @@ typedef struct VhostOps { vhost_get_device_id_op vhost_get_device_id; vhost_force_iommu_op vhost_force_iommu; vhost_set_config_call_op vhost_set_config_call; + vhost_reset_status_op vhost_reset_status; } VhostOps; int vhost_backend_update_device_iotlb(struct vhost_dev *dev, diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c index cbbe92ffe8..26e38a6aab 100644 --- a/hw/virtio/vhost-vdpa.c +++ b/hw/virtio/vhost-vdpa.c @@ -1152,14 +1152,23 @@ static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started) if (started) { memory_listener_register(&v->listener, &address_space_memory); return vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK); - } else { - vhost_vdpa_reset_device(dev); - vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE | - VIRTIO_CONFIG_S_DRIVER); - memory_listener_unregister(&v->listener); + } - return 0; + return 0; +} + +static void vhost_vdpa_reset_status(struct vhost_dev *dev) +{ + struct vhost_vdpa *v = dev->opaque; + + if (dev->vq_index + dev->nvqs != dev->vq_index_end) { + return; } + + vhost_vdpa_reset_device(dev); + vhost_vdpa_add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE | + VIRTIO_CONFIG_S_DRIVER); + memory_listener_unregister(&v->listener); } static int vhost_vdpa_set_log_base(struct vhost_dev *dev, uint64_t base, @@ -1346,4 +1355,5 @@ const VhostOps vdpa_ops = { .vhost_vq_get_addr = vhost_vdpa_vq_get_addr, .vhost_force_iommu = vhost_vdpa_force_iommu, .vhost_set_config_call = vhost_vdpa_set_config_call, + .vhost_reset_status = vhost_vdpa_reset_status, }; diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index eb8c4c378c..a266396576 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -2049,6 +2049,9 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) hdev->vqs + i, hdev->vq_index + i); } + if (hdev->vhost_ops->vhost_reset_status) { + hdev->vhost_ops->vhost_reset_status(hdev); + } if (vhost_dev_has_iommu(hdev)) { if (hdev->vhost_ops->vhost_set_iotlb_callback) {
The function vhost.c:vhost_dev_stop calls vhost operation vhost_dev_start(false). In the case of vdpa it totally reset and wipes the device, making the fetching of the vring base (virtqueue state) totally useless. The kernel backend does not use vhost_dev_start vhost op callback, but vhost-user do. A patch to make vhost_user_dev_start more similar to vdpa is desirable, but it can be added on top. Signed-off-by: Eugenio Pérez <eperezma@redhat.com> --- include/hw/virtio/vhost-backend.h | 4 ++++ hw/virtio/vhost-vdpa.c | 22 ++++++++++++++++------ hw/virtio/vhost.c | 3 +++ 3 files changed, 23 insertions(+), 6 deletions(-)