| Message ID | 20220214081416.117695-20-xuanzhuo@linux.alibaba.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | virtio pci support VIRTIO_F_RING_RESET | expand |
On Mon, Feb 14, 2022 at 4:15 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: > > Added helper virtio_set_max_ring_num() to set the upper limit of ring > num when creating a virtqueue. > > Can be used to limit ring num before find_vqs() call. Or change ring num > when re-enable reset queue. Do we have a chance that RX and TX may want different ring size? If yes, it might be even better to have per vq limit via find_vqs()? > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > --- > drivers/virtio/virtio_ring.c | 6 ++++++ > include/linux/virtio.h | 1 + > include/linux/virtio_config.h | 30 ++++++++++++++++++++++++++++++ > 3 files changed, 37 insertions(+) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index 1a123b5e5371..a77a82883e44 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -943,6 +943,9 @@ static struct virtqueue *vring_create_virtqueue_split( > size_t queue_size_in_bytes; > struct vring vring; > > + if (vdev->max_ring_num && num > vdev->max_ring_num) > + num = vdev->max_ring_num; > + > /* We assume num is a power of 2. */ > if (num & (num - 1)) { > dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num); > @@ -1692,6 +1695,9 @@ static struct virtqueue *vring_create_virtqueue_packed( > dma_addr_t ring_dma_addr, driver_event_dma_addr, device_event_dma_addr; > size_t ring_size_in_bytes, event_size_in_bytes; > > + if (vdev->max_ring_num && num > vdev->max_ring_num) > + num = vdev->max_ring_num; > + > ring_size_in_bytes = num * sizeof(struct vring_packed_desc); > > ring = vring_alloc_queue(vdev, ring_size_in_bytes, > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > index 1153b093c53d..45525beb2ec4 100644 > --- a/include/linux/virtio.h > +++ b/include/linux/virtio.h > @@ -127,6 +127,7 @@ struct virtio_device { > struct list_head vqs; > u64 features; > void *priv; > + u16 max_ring_num; > }; > > static inline struct virtio_device *dev_to_virtio(struct device *_dev) > diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h > index cd7f7f44ce38..d7cb2d0341ee 100644 > --- a/include/linux/virtio_config.h > +++ b/include/linux/virtio_config.h > @@ -200,6 +200,36 @@ static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev) > return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM); > } > > +/** > + * virtio_set_max_ring_num - set max ring num > + * @vdev: the device > + * @num: max ring num. Zero clear the limit. > + * > + * When creating a virtqueue, use this value as the upper limit of ring num. > + * > + * Returns 0 on success or error status > + */ > +static inline > +int virtio_set_max_ring_num(struct virtio_device *vdev, u16 num) > +{ Having a dedicated helper for a per device parameter usually means the use cases are greatly limited. For example, this seems can only be used when DRIVER_OK is not set? And in patch 17 this function is called even if we only modify the RX size, this is probably another call for a more flexible API as I suggest like exporting vring allocation/deallocation helper and extend find_vqs()? Thanks > + if (!num) { > + vdev->max_ring_num = num; > + return 0; > + } > + > + if (!virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > + if (!is_power_of_2(num)) { > + num = __rounddown_pow_of_two(num); > + > + if (!num) > + return -EINVAL; > + } > + } > + > + vdev->max_ring_num = num; > + return 0; > +} > + > static inline > struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev, > vq_callback_t *c, const char *n) > -- > 2.31.0 >
On Wed, 16 Feb 2022 12:14:04 +0800, Jason Wang <jasowang@redhat.com> wrote: > On Mon, Feb 14, 2022 at 4:15 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote: > > > > Added helper virtio_set_max_ring_num() to set the upper limit of ring > > num when creating a virtqueue. > > > > Can be used to limit ring num before find_vqs() call. Or change ring num > > when re-enable reset queue. > > Do we have a chance that RX and TX may want different ring size? If > yes, it might be even better to have per vq limit via find_vqs()? > > > > > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> > > --- > > drivers/virtio/virtio_ring.c | 6 ++++++ > > include/linux/virtio.h | 1 + > > include/linux/virtio_config.h | 30 ++++++++++++++++++++++++++++++ > > 3 files changed, 37 insertions(+) > > > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > > index 1a123b5e5371..a77a82883e44 100644 > > --- a/drivers/virtio/virtio_ring.c > > +++ b/drivers/virtio/virtio_ring.c > > @@ -943,6 +943,9 @@ static struct virtqueue *vring_create_virtqueue_split( > > size_t queue_size_in_bytes; > > struct vring vring; > > > > + if (vdev->max_ring_num && num > vdev->max_ring_num) > > + num = vdev->max_ring_num; > > + > > /* We assume num is a power of 2. */ > > if (num & (num - 1)) { > > dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num); > > @@ -1692,6 +1695,9 @@ static struct virtqueue *vring_create_virtqueue_packed( > > dma_addr_t ring_dma_addr, driver_event_dma_addr, device_event_dma_addr; > > size_t ring_size_in_bytes, event_size_in_bytes; > > > > + if (vdev->max_ring_num && num > vdev->max_ring_num) > > + num = vdev->max_ring_num; > > + > > ring_size_in_bytes = num * sizeof(struct vring_packed_desc); > > > > ring = vring_alloc_queue(vdev, ring_size_in_bytes, > > diff --git a/include/linux/virtio.h b/include/linux/virtio.h > > index 1153b093c53d..45525beb2ec4 100644 > > --- a/include/linux/virtio.h > > +++ b/include/linux/virtio.h > > @@ -127,6 +127,7 @@ struct virtio_device { > > struct list_head vqs; > > u64 features; > > void *priv; > > + u16 max_ring_num; > > }; > > > > static inline struct virtio_device *dev_to_virtio(struct device *_dev) > > diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h > > index cd7f7f44ce38..d7cb2d0341ee 100644 > > --- a/include/linux/virtio_config.h > > +++ b/include/linux/virtio_config.h > > @@ -200,6 +200,36 @@ static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev) > > return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM); > > } > > > > +/** > > + * virtio_set_max_ring_num - set max ring num > > + * @vdev: the device > > + * @num: max ring num. Zero clear the limit. > > + * > > + * When creating a virtqueue, use this value as the upper limit of ring num. > > + * > > + * Returns 0 on success or error status > > + */ > > +static inline > > +int virtio_set_max_ring_num(struct virtio_device *vdev, u16 num) > > +{ > > Having a dedicated helper for a per device parameter usually means the > use cases are greatly limited. For example, this seems can only be > used when DRIVER_OK is not set? > > And in patch 17 this function is called even if we only modify the RX > size, this is probably another call for a more flexible API as I > suggest like exporting vring allocation/deallocation helper and extend > find_vqs()? > I understand. Thanks. > Thanks > > > > + if (!num) { > > + vdev->max_ring_num = num; > > + return 0; > > + } > > + > > + if (!virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) { > > + if (!is_power_of_2(num)) { > > + num = __rounddown_pow_of_two(num); > > + > > + if (!num) > > + return -EINVAL; > > + } > > + } > > + > > + vdev->max_ring_num = num; > > + return 0; > > +} > > + > > static inline > > struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev, > > vq_callback_t *c, const char *n) > > -- > > 2.31.0 > > >
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 1a123b5e5371..a77a82883e44 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -943,6 +943,9 @@ static struct virtqueue *vring_create_virtqueue_split( size_t queue_size_in_bytes; struct vring vring; + if (vdev->max_ring_num && num > vdev->max_ring_num) + num = vdev->max_ring_num; + /* We assume num is a power of 2. */ if (num & (num - 1)) { dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num); @@ -1692,6 +1695,9 @@ static struct virtqueue *vring_create_virtqueue_packed( dma_addr_t ring_dma_addr, driver_event_dma_addr, device_event_dma_addr; size_t ring_size_in_bytes, event_size_in_bytes; + if (vdev->max_ring_num && num > vdev->max_ring_num) + num = vdev->max_ring_num; + ring_size_in_bytes = num * sizeof(struct vring_packed_desc); ring = vring_alloc_queue(vdev, ring_size_in_bytes, diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 1153b093c53d..45525beb2ec4 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -127,6 +127,7 @@ struct virtio_device { struct list_head vqs; u64 features; void *priv; + u16 max_ring_num; }; static inline struct virtio_device *dev_to_virtio(struct device *_dev) diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h index cd7f7f44ce38..d7cb2d0341ee 100644 --- a/include/linux/virtio_config.h +++ b/include/linux/virtio_config.h @@ -200,6 +200,36 @@ static inline bool virtio_has_dma_quirk(const struct virtio_device *vdev) return !virtio_has_feature(vdev, VIRTIO_F_ACCESS_PLATFORM); } +/** + * virtio_set_max_ring_num - set max ring num + * @vdev: the device + * @num: max ring num. Zero clear the limit. + * + * When creating a virtqueue, use this value as the upper limit of ring num. + * + * Returns 0 on success or error status + */ +static inline +int virtio_set_max_ring_num(struct virtio_device *vdev, u16 num) +{ + if (!num) { + vdev->max_ring_num = num; + return 0; + } + + if (!virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) { + if (!is_power_of_2(num)) { + num = __rounddown_pow_of_two(num); + + if (!num) + return -EINVAL; + } + } + + vdev->max_ring_num = num; + return 0; +} + static inline struct virtqueue *virtio_find_single_vq(struct virtio_device *vdev, vq_callback_t *c, const char *n)
Added helper virtio_set_max_ring_num() to set the upper limit of ring num when creating a virtqueue. Can be used to limit ring num before find_vqs() call. Or change ring num when re-enable reset queue. Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> --- drivers/virtio/virtio_ring.c | 6 ++++++ include/linux/virtio.h | 1 + include/linux/virtio_config.h | 30 ++++++++++++++++++++++++++++++ 3 files changed, 37 insertions(+)