Re: [PATCH v2 1/3] virtio_ring: Allow non power of 2 sizes for packed virtqueue
On 2023-03-16 p.m.11:16, Jason Wang wrote: External email: Use caution opening links or attachments On Thu, Mar 16, 2023 at 2:55 AM Feng Liu wrote: According to the Virtio Specification, the Queue Size parameter of a virtqueue corresponds to the maximum number of descriptors in that queue, and it does not have to be a power of 2 for packed virtqueues. However, the virtio_pci_modern driver enforced a power of 2 check for virtqueue sizes, which is unnecessary and restrictive for packed virtuqueue. Split virtqueue still needs to check the virtqueue size is power_of_2 which has been done in vring_alloc_queue_split of the virtio_ring layer. To validate this change, we tested various virtqueue sizes for packed rings, including 128, 256, 512, 100, 200, 500, and 1000, with CONFIG_PAGE_POISONING enabled, and all tests passed successfully. Signed-off-by: Feng Liu Reviewed-by: Jiri Pirko Acked-by: Jason Wang Thanks Hi Michael & Jason Could you please help to take these reviewed/acked patches forward? Thanks so much --- v0 -> v1 feedbacks from Jason Wang and Michael S. Tsirkin - remove power_of_2 check of virtqueue size v1 -> v2 feedbacks from Parav Pandit and Jiri Pirko - keep power_of_2 check of split virtqueue in vring_alloc_queue_split of virtio_ring layer. --- drivers/virtio/virtio_pci_modern.c | 5 - 1 file changed, 5 deletions(-) diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index 9e496e288cfa..6e713904d8e8 100644 --- a/drivers/virtio/virtio_pci_modern.c +++ b/drivers/virtio/virtio_pci_modern.c @@ -310,11 +310,6 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev, if (!num || vp_modern_get_queue_enable(mdev, index)) return ERR_PTR(-ENOENT); - if (!is_power_of_2(num)) { - dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num); - return ERR_PTR(-EINVAL); - } - info->msix_vector = msix_vec; /* create the vring */ -- 2.34.1 ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
Re: [PATCH v2 1/3] virtio_ring: Allow non power of 2 sizes for packed virtqueue
Feng Liu writes: > According to the Virtio Specification, the Queue Size parameter of a > virtqueue corresponds to the maximum number of descriptors in that > queue, and it does not have to be a power of 2 for packed virtqueues. > However, the virtio_pci_modern driver enforced a power of 2 check for > virtqueue sizes, which is unnecessary and restrictive for packed > virtuqueue. > > Split virtqueue still needs to check the virtqueue size is power_of_2 > which has been done in vring_alloc_queue_split of the virtio_ring layer. > > To validate this change, we tested various virtqueue sizes for packed > rings, including 128, 256, 512, 100, 200, 500, and 1000, with > CONFIG_PAGE_POISONING enabled, and all tests passed successfully. > > Signed-off-by: Feng Liu > Reviewed-by: Jiri Pirko > Reviewed-by: David Edmondson > --- > v0 -> v1 > feedbacks from Jason Wang and Michael S. Tsirkin > - remove power_of_2 check of virtqueue size > > v1 -> v2 > feedbacks from Parav Pandit and Jiri Pirko > - keep power_of_2 check of split virtqueue in vring_alloc_queue_split of > virtio_ring layer. > --- > drivers/virtio/virtio_pci_modern.c | 5 - > 1 file changed, 5 deletions(-) > > diff --git a/drivers/virtio/virtio_pci_modern.c > b/drivers/virtio/virtio_pci_modern.c > index 9e496e288cfa..6e713904d8e8 100644 > --- a/drivers/virtio/virtio_pci_modern.c > +++ b/drivers/virtio/virtio_pci_modern.c > @@ -310,11 +310,6 @@ static struct virtqueue *setup_vq(struct > virtio_pci_device *vp_dev, > if (!num || vp_modern_get_queue_enable(mdev, index)) > return ERR_PTR(-ENOENT); > > - if (!is_power_of_2(num)) { > - dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num); > - return ERR_PTR(-EINVAL); > - } > - > info->msix_vector = msix_vec; > > /* create the vring */ > -- > 2.34.1 -- Do not leave the building. ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
Re: [PATCH v2 1/3] virtio_ring: Allow non power of 2 sizes for packed virtqueue
On Thu, Mar 16, 2023 at 2:55 AM Feng Liu wrote: > > According to the Virtio Specification, the Queue Size parameter of a > virtqueue corresponds to the maximum number of descriptors in that > queue, and it does not have to be a power of 2 for packed virtqueues. > However, the virtio_pci_modern driver enforced a power of 2 check for > virtqueue sizes, which is unnecessary and restrictive for packed > virtuqueue. > > Split virtqueue still needs to check the virtqueue size is power_of_2 > which has been done in vring_alloc_queue_split of the virtio_ring layer. > > To validate this change, we tested various virtqueue sizes for packed > rings, including 128, 256, 512, 100, 200, 500, and 1000, with > CONFIG_PAGE_POISONING enabled, and all tests passed successfully. > > Signed-off-by: Feng Liu > Reviewed-by: Jiri Pirko Acked-by: Jason Wang Thanks > > --- > v0 -> v1 > feedbacks from Jason Wang and Michael S. Tsirkin > - remove power_of_2 check of virtqueue size > > v1 -> v2 > feedbacks from Parav Pandit and Jiri Pirko > - keep power_of_2 check of split virtqueue in vring_alloc_queue_split of > virtio_ring layer. > --- > drivers/virtio/virtio_pci_modern.c | 5 - > 1 file changed, 5 deletions(-) > > diff --git a/drivers/virtio/virtio_pci_modern.c > b/drivers/virtio/virtio_pci_modern.c > index 9e496e288cfa..6e713904d8e8 100644 > --- a/drivers/virtio/virtio_pci_modern.c > +++ b/drivers/virtio/virtio_pci_modern.c > @@ -310,11 +310,6 @@ static struct virtqueue *setup_vq(struct > virtio_pci_device *vp_dev, > if (!num || vp_modern_get_queue_enable(mdev, index)) > return ERR_PTR(-ENOENT); > > - if (!is_power_of_2(num)) { > - dev_warn(&vp_dev->pci_dev->dev, "bad queue size %u", num); > - return ERR_PTR(-EINVAL); > - } > - > info->msix_vector = msix_vec; > > /* create the vring */ > -- > 2.34.1 > ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization