在 2022/8/16 09:06, Kangjie Xu 写道:
The virtio queue reset function has already been defined in the virtio spec 1.2. The relevant virtio spec information is here: https://github.com/oasis-tcs/virtio-spec/issues/124 https://github.com/oasis-tcs/virtio-spec/issues/139 This patch set is to support this function in QEMU. It consists of several parts: 1. Patches 1-7 are the basic interfaces for vq reset in virtio and virtio-pci. 2. Patches 8-12 support vq stop and vq restart for vhost-kernel. 3. Patches 13-19 support vq stop and vq restart for vhost-user. 4. Patches 20-22 support vq reset and re-enable for virtio-net. 5. Patches 23-24 enable the vq reset feature for vhost-kernel and vhost-user. The process of virtqueue reset can be concluded as: 1. The virtqueue is disabled when VIRTIO_PCI_COMMON_Q_RESET is written. 2. Then the virtqueue can be optionally restarted(re-enabled). Since this patch set involves multiple modules and seems a bit messy, we briefly describe the calling process for different modes below. virtio-net: 1. VIRTIO_PCI_COMMON_Q_RESET is written [virtio-pci] -> virtio_queue_reset() [virtio] -> virtio_net_queue_reset() [virtio-net] -> __virtio_queue_reset() 2. VIRTIO_PCI_COMMON_Q_ENABLE is written [virtio-pci] -> set enabled, reset status of vq. vhost-kernel: 1. VIRTIO_PCI_COMMON_Q_RESET is written [virtio-pci] -> virtio_queue_reset() [virtio] -> virtio_net_queue_reset() [virtio-net] -> vhost_net_virtqueue_stop() [vhost-net] -> vhost_net_set_backend() [vhost] -> vhost_dev_virtqueue_stop() -> vhost_virtqueue_unmap() -> __virtio_queue_reset() 2. VIRTIO_PCI_COMMON_Q_ENABLE is written [virtio-pci] -> virtio_queue_enable() [virtio] -> virtio_net_queue_enable() [virtio-net] -> vhost_net_virtqueue_restart() [vhost-net] -> vhost_dev_virtqueue_restart() [vhost] -> vhost_virtqueue_start() -> vhost_net_set_backend() -> set enabled, reset status of vq. vhost-user: 1. VIRTIO_PCI_COMMON_Q_RESET is written [virtio-pci] -> virtio_queue_reset() [virtio] -> virtio_net_queue_reset() [virtio-net] -> vhost_net_virtqueue_stop() [vhost-net] -> vhost_dev_virtqueue_stop() [vhost] -> vhost_user_reset_vring() [vhost-user] -> send VHOST_USER_RESET_VRING to the device -> vhost_virtqueue_unmap() -> __virtio_queue_reset() 2. VIRTIO_PCI_COMMON_Q_ENABLE is written [virtio-pci] -> virtio_queue_enable() [virtio] -> virtio_net_queue_enable() [virtio-net] -> vhost_net_virtqueue_restart() [vhost-net] -> vhost_dev_virtqueue_restart() [vhost] -> vhost_virtqueue_start() -> vhost_user_set_single_vring_enable [vhost-user] -> send VHOST_USER_SET_VRING_ENABLE to the device -> set enabled, reset status of vq. Test environment: Host: 5.19.0-rc3 (With vq reset support) Qemu: QEMU emulator version 7.0.50 Guest: 5.19.0-rc3 (With vq reset support) DPDK: 22.07-rc1 (With vq reset support) Test Cmd: ethtool -g eth1; ethtool -G eth1 rx $1 tx $2; ethtool -g eth1; The drvier can resize the virtio queue, then virtio queue reset function should be triggered. The default is split mode, modify Qemu virtio-net to add PACKED feature to test packed mode. Guest Kernel Patch: https://lore.kernel.org/bpf/20220801063902.129329-1-xuanz...@linux.alibaba.com/ DPDK Patch: https://github.com/middaywords/dpdk/compare/72206323a5dd3182b13f61b25a64abdddfee595c...eabadfac7953da66bc10ffb8284b490d09bb7ec7 Host Kernel Patch: https://github.com/middaywords/linux/commit/19a91e0d7167b2031e46078c6215c213b89cb2c3 Looking forward to your review and comments. Thanks.
I suggest to split vhost-user part into another series since: 1) vhost-net kernel is ready for this future 2) vhost-user probably requires some extensions of the current protocol Then it can speed up the merging and reduce the rebasing of a huge series. Thanks
Kangjie Xu (19): virtio: introduce virtio_queue_enable() virtio: core: vq reset feature negotation support virtio-pci: support queue enable vhost: extract the logic of unmapping the vrings and desc vhost: introduce vhost_dev_virtqueue_stop() vhost: introduce vhost_dev_virtqueue_restart() vhost-net: vhost-kernel: introduce vhost_net_virtqueue_stop() vhost-net: vhost-kernel: introduce vhost_net_virtqueue_restart() docs: vhost-user: add VHOST_USER_RESET_VRING message vhost-user: introduce vhost_reset_vring() interface vhost-user: add op to enable or disable a single vring vhost: vhost-user: update vhost_dev_virtqueue_stop() vhost: vhost-user: update vhost_dev_virtqueue_restart() vhost-net: vhost-user: update vhost_net_virtqueue_stop() vhost-net: vhost-user: update vhost_net_virtqueue_restart() virtio-net: introduce flush_or_purge_queued_packets() virtio-net: support queue_enable vhost: vhost-kernel: enable vq reset feature vhost: vhost-user: enable vq reset feature Xuan Zhuo (5): virtio: sync relevant definitions with linux virtio: introduce __virtio_queue_reset() virtio: introduce virtio_queue_reset() virtio-pci: support queue reset virtio-net: support queue reset docs/interop/vhost-user.rst | 10 +++ hw/core/machine.c | 1 + hw/net/vhost_net.c | 79 +++++++++++++++++++ hw/net/virtio-net.c | 58 ++++++++++++-- hw/virtio/vhost-user.c | 67 ++++++++++++++-- hw/virtio/vhost.c | 79 +++++++++++++++++-- hw/virtio/virtio-pci.c | 20 +++++ hw/virtio/virtio.c | 62 +++++++++++---- include/hw/virtio/vhost-backend.h | 6 ++ include/hw/virtio/vhost.h | 5 ++ include/hw/virtio/virtio-pci.h | 1 + include/hw/virtio/virtio.h | 8 +- include/net/vhost_net.h | 4 + .../standard-headers/linux/virtio_config.h | 5 ++ include/standard-headers/linux/virtio_pci.h | 2 + 15 files changed, 371 insertions(+), 36 deletions(-)