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.
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(-)
--
2.32.0
