Re: [PATCH v7 00/26] virtio pci support VIRTIO_F_RING_RESET

Michael S. Tsirkin
2022-03-09T09:02:39Z

On Wed, Mar 09, 2022 at 12:45:57PM +0800, Jason Wang wrote:
>
> 在 2022/3/8 下午8:34, Xuan Zhuo 写道:
> > The virtio spec already supports the virtio queue reset function. This patch set
> > is to add this function to the kernel. The relevant virtio spec information is
> > here:
> >
> > https://github.com/oasis-tcs/virtio-spec/issues/124
> >
> > Also regarding MMIO support for queue reset, I plan to support it after this
> > patch is passed.
> >
> > Performing reset on a queue is divided into four steps:
> > 1. virtio_reset_vq() - notify the device to reset the queue
> > 2. virtqueue_detach_unused_buf() - recycle the buffer submitted
> > 3. virtqueue_reset_vring() - reset the vring (may re-alloc)
> > 4. virtio_enable_resetq() - mmap vring to device, and enable the queue
> >
> > The first part 1-17 of this patch set implements virtio pci's support and API
> > for queue reset. The latter part is to make virtio-net support set_ringparam. Do
> > these things for this feature:
> >
> > 1. virtio-net support rx,tx reset
> > 2. find_vqs() support to special the max size of each vq
> > 3. virtio-net support set_ringparam
> >
> > #1 -#3 : prepare
> > #4 -#12: virtio ring support reset vring of the vq
> > #13-#14: add helper
> > #15-#17: virtio pci support reset queue and re-enable
> > #18-#21: find_vqs() support sizes to special the max size of each vq
> > #23-#24: virtio-net support rx, tx reset
> > #22, #25, #26: virtio-net support set ringparam
> >
> > Test environment:
> > Host: 4.19.91
> > Qemu: QEMU emulator version 6.2.50 (with vq reset support)
> > Test Cmd: ethtool -G eth1 rx $1 tx $2; ethtool -g eth1
> >
> > The default is split mode, modify Qemu virtio-net to add PACKED feature to test
> > packed mode.
> >
> >
> > Please review. Thanks.
> >
> > v7:
> > 1. fix #6 subject typo
> > 2. fix #6 ring_size_in_bytes is uninitialized
> > 3. check by: make W=12
> >
> > v6:
> > 1. virtio_pci: use synchronize_irq(irq) to sync the irq callbacks
> > 2. Introduce virtqueue_reset_vring() to implement the reset of vring during
> > the reset process. May use the old vring if num of the vq not change.
> > 3. find_vqs() support sizes to special the max size of each vq
> >
> > v5:
> > 1. add virtio-net support set_ringparam
> >
> > v4:
> > 1. just the code of virtio, without virtio-net
> > 2. Performing reset on a queue is divided into these steps:
> > 1. reset_vq: reset one vq
> > 2. recycle the buffer from vq by virtqueue_detach_unused_buf()
> > 3. release the ring of the vq by vring_release_virtqueue()
> > 4. enable_reset_vq: re-enable the reset queue
> > 3. Simplify the parameters of enable_reset_vq()
> > 4. add container structures for virtio_pci_common_cfg
> >
> > v3:
> > 1. keep vq, irq unreleased
>
>
> The series became kind of huge.
>
> I'd suggest to split it into two series.
>
> 1) refactoring of the virtio_ring to prepare for the resize
> 2) the reset support + virtio-net support
>
> Thanks

And just to clarify, I think you mean all the "extract logic"
things need to also go into the refactoring part, right?
Just making 3 first patches a series by themselves won't help ...
I'm kind of ambivalent on the splitup - both parts
need work for now, so I wonder how does it help.
But if you care about it, I don't mind.

> >
> > *** BLURB HERE ***

You don't want this in your cover letters btw.

> > Xuan Zhuo (26):
> > virtio_pci: struct virtio_pci_common_cfg add queue_notify_data
> > virtio: queue_reset: add VIRTIO_F_RING_RESET
> > virtio: add helper virtqueue_get_vring_max_size()
> > virtio_ring: split: extract the logic of creating vring
> > virtio_ring: split: extract the logic of init vq and attach vring
> > virtio_ring: packed: extract the logic of creating vring
> > virtio_ring: packed: extract the logic of init vq and attach vring
> > virtio_ring: extract the logic of freeing vring
> > virtio_ring: split: implement virtqueue_reset_vring_split()
> > virtio_ring: packed: implement virtqueue_reset_vring_packed()
> > virtio_ring: introduce virtqueue_reset_vring()
> > virtio_ring: update the document of the virtqueue_detach_unused_buf
> > for queue reset
> > virtio: queue_reset: struct virtio_config_ops add callbacks for
> > queue_reset
> > virtio: add helper for queue reset
> > virtio_pci: queue_reset: update struct virtio_pci_common_cfg and
> > option functions
> > virtio_pci: queue_reset: extract the logic of active vq for modern pci
> > virtio_pci: queue_reset: support VIRTIO_F_RING_RESET
> > virtio: find_vqs() add arg sizes
> > virtio_pci: support the arg sizes of find_vqs()
> > virtio_mmio: support the arg sizes of find_vqs()
> > virtio: add helper virtio_find_vqs_ctx_size()
> > virtio_net: get ringparam by virtqueue_get_vring_max_size()
> > virtio_net: split free_unused_bufs()
> > virtio_net: support rx/tx queue reset
> > virtio_net: set the default max ring size by find_vqs()
> > virtio_net: support set_ringparam
> >
> > arch/um/drivers/virtio_uml.c | 2 +-
> > drivers/net/virtio_net.c | 257 ++++++++--
> > drivers/platform/mellanox/mlxbf-tmfifo.c | 3 +-
> > drivers/remoteproc/remoteproc_virtio.c | 2 +-
> > drivers/s390/virtio/virtio_ccw.c | 2 +-
> > drivers/virtio/virtio_mmio.c | 12 +-
> > drivers/virtio/virtio_pci_common.c | 28 +-
> > drivers/virtio/virtio_pci_common.h | 3 +-
> > drivers/virtio/virtio_pci_legacy.c | 8 +-
> > drivers/virtio/virtio_pci_modern.c | 146 +++++-
> > drivers/virtio/virtio_pci_modern_dev.c | 36 ++
> > drivers/virtio/virtio_ring.c | 584 +++++++++++++++++------
> > drivers/virtio/virtio_vdpa.c | 2 +-
> > include/linux/virtio.h | 12 +
> > include/linux/virtio_config.h | 74 ++-
> > include/linux/virtio_pci_modern.h | 2 +
> > include/uapi/linux/virtio_config.h | 7 +-
> > include/uapi/linux/virtio_pci.h | 14 +
> > 18 files changed, 979 insertions(+), 215 deletions(-)
> >
> > --
> > 2.31.0
> >