> On Feb 15, 2022, at 4:44 PM, Jason Wang <jasowang@xxxxxxxxxx> wrote: > > On Tue, Feb 15, 2022 at 4:15 PM Junji Wei <weijunji@xxxxxxxxxxxxx> wrote: >> >> Hi all, >> >> This RFC aims to introduce our recent work on VirtIO-RDMA. >> >> We have finished a draft of VirtIO-RDMA specification and a vhost-user >> RDMA demo based on the spec.This demo can work with CM/Socket >> and UD/RC QP now. >> >> NOTE that this spec now only focuses on emulating a soft >> RoCE (RDMA over Converged Ethernet) device with normal Network Interface >> Card (without RDMA capability). So most Infiniband (IB) specific features >> such as Subnet Manager (SM), Local Identifier (LID) and Automatic Path >> Migration (APM) are not covered in this specification. >> >> There are four parts of our work: >> >> 1. VirtIO-RDMA driver in linux kernel: >> https://github.com/weijunji/linux/tree/virtio-rdma-patch >> >> 2. VirtIO-RDMA userspace provider in rdma-core: >> https://github.com/weijunji/rdma-core/tree/virtio-rdma >> >> 3. VHost-User RDMA backend in QEMU: >> https://github.com/weijunji/qemu/tree/vhost-user-rdma >> >> 4. VHost-User RDMA demo implements with DPDK: >> https://github.com/weijunji/dpdk-rdma >> >> >> To test with our demo: >> >> 1. Build Linux kernel with config INFINIBAND_VIRTIO_RDMA >> >> 2. Build QEMU with config VHOST_USER_RDMA >> >> 3. Build rdma-core and install it to VM image >> >> 4. Build and install DPDK(NOTE that we only tested on DPDK 20.11.3) >> >> 5. Build dpdk-rdma: >> $ cd dpdk-rdma >> $ meson build >> $ cd build >> $ ninja >> >> 6. Run dpdk-rdma: >> $ sudo ./dpdk-rdma --vdev 'net_vhost0,iface=/tmp/sock0,queues=1' \ >> --vdev 'net_tap0' --lcore '1-3' >> $ sudo brctl addif virbr0 dtap0 >> >> 7. Boot kernel with qemu with following args using libvirt: >> <qemu:commandline> >> <qemu:arg value='-chardev'/> >> <qemu:arg value='socket,path=/tmp/sock0,id=vunet'/> >> <qemu:arg value='-netdev'/> >> <qemu:arg value='vhost-user,id=net1,chardev=vunet,vhostforce,queues=1'/> >> <qemu:arg value='-device'/> >> <qemu:arg value='virtio-net-pci,netdev=net1,bus=pci.0,multifunction=on,addr=0x2'/> >> <qemu:arg value='-chardev'/> >> <qemu:arg value='socket,path=/tmp/vhost-rdma0,id=vurdma'/> >> <qemu:arg value='-device'/> >> <qemu:arg value='vhost-user-rdma-pci,page-per-vq,disable-legacy=on,addr=2.1,chardev=vurdma'/> >> </qemu:commandline> >> >> NOTE that virtio-net-pci and vhost-user-rdma-pci MUST in same PCI addresss. >> > > A silly question, if RoCE is the focus, why not extending virtio-net instead? I think it's OK to extend virtio-net to implement virtio-rdma. But if we want to support IB in the future, would it be better to implement the virtio-rdma in an independent way? And currently virtio-rdma doesn't have a strong dependency on virtio-net (except for gid and ah stuffs). Is it OK to mix them up? Thanks.
