On Mon, Oct 16, 2023 at 8:00 PM Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> wrote: > > ## AF_XDP > > XDP socket(AF_XDP) is an excellent bypass kernel network framework. The zero > copy feature of xsk (XDP socket) needs to be supported by the driver. The > performance of zero copy is very good. mlx5 and intel ixgbe already support > this feature, This patch set allows virtio-net to support xsk's zerocopy xmit > feature. > > At present, we have completed some preparation: > > 1. vq-reset (virtio spec and kernel code) > 2. virtio-core premapped dma > 3. virtio-net xdp refactor > > So it is time for Virtio-Net to complete the support for the XDP Socket > Zerocopy. > > Virtio-net can not increase the queue num at will, so xsk shares the queue with > kernel. > > On the other hand, Virtio-Net does not support generate interrupt from driver > manually, so when we wakeup tx xmit, we used some tips. If the CPU run by TX > NAPI last time is other CPUs, use IPI to wake up NAPI on the remote CPU. If it > is also the local CPU, then we wake up napi directly. > > This patch set includes some refactor to the virtio-net to let that to support > AF_XDP. > > ## performance > > ENV: Qemu with vhost-user(polling mode). > > Sockperf: https://github.com/Mellanox/sockperf > I use this tool to send udp packet by kernel syscall. > > xmit command: sockperf tp -i 10.0.3.1 -t 1000 > > I write a tool that sends udp packets or recvs udp packets by AF_XDP. > > | Guest APP CPU |Guest Softirq CPU | UDP PPS > ------------------|---------------|------------------|------------ > xmit by syscall | 100% | | 676,915 > xmit by xsk | 59.1% | 100% | 5,447,168 > recv by syscall | 60% | 100% | 932,288 > recv by xsk | 35.7% | 100% | 3,343,168 Any chance we can get a testpmd result (which I guess should be better than PPS above)? Thanks > > ## maintain > > I am currently a reviewer for virtio-net. I commit to maintain AF_XDP support in > virtio-net. > > Please review. > > Thanks. > > v1: > 1. remove two virtio commits. Push this patchset to net-next > 2. squash "virtio_net: virtnet_poll_tx support rescheduled" to xsk: support tx > 3. fix some warnings > > Xuan Zhuo (19): > virtio_net: rename free_old_xmit_skbs to free_old_xmit > virtio_net: unify the code for recycling the xmit ptr > virtio_net: independent directory > virtio_net: move to virtio_net.h > virtio_net: add prefix virtnet to all struct/api inside virtio_net.h > virtio_net: separate virtnet_rx_resize() > virtio_net: separate virtnet_tx_resize() > virtio_net: sq support premapped mode > virtio_net: xsk: bind/unbind xsk > virtio_net: xsk: prevent disable tx napi > virtio_net: xsk: tx: support tx > virtio_net: xsk: tx: support wakeup > virtio_net: xsk: tx: virtnet_free_old_xmit() distinguishes xsk buffer > virtio_net: xsk: tx: virtnet_sq_free_unused_buf() check xsk buffer > virtio_net: xsk: rx: introduce add_recvbuf_xsk() > virtio_net: xsk: rx: introduce receive_xsk() to recv xsk buffer > virtio_net: xsk: rx: virtnet_rq_free_unused_buf() check xsk buffer > virtio_net: update tx timeout record > virtio_net: xdp_features add NETDEV_XDP_ACT_XSK_ZEROCOPY > > MAINTAINERS | 2 +- > drivers/net/Kconfig | 8 +- > drivers/net/Makefile | 2 +- > drivers/net/virtio/Kconfig | 13 + > drivers/net/virtio/Makefile | 8 + > drivers/net/{virtio_net.c => virtio/main.c} | 652 +++++++++----------- > drivers/net/virtio/virtio_net.h | 359 +++++++++++ > drivers/net/virtio/xsk.c | 545 ++++++++++++++++ > drivers/net/virtio/xsk.h | 32 + > 9 files changed, 1247 insertions(+), 374 deletions(-) > create mode 100644 drivers/net/virtio/Kconfig > create mode 100644 drivers/net/virtio/Makefile > rename drivers/net/{virtio_net.c => virtio/main.c} (91%) > create mode 100644 drivers/net/virtio/virtio_net.h > create mode 100644 drivers/net/virtio/xsk.c > create mode 100644 drivers/net/virtio/xsk.h > > -- > 2.32.0.3.g01195cf9f >
