Hi Jason, Yes, the work to support RSS in the Linux virtio-net driver is in progress. https://bugzilla.redhat.com/show_bug.cgi?id=1912082
On Fri, Apr 2, 2021 at 5:57 AM Jason Wang <jasow...@redhat.com> wrote: > > > 在 2021/3/25 下午11:35, Andrew Melnychenko 写道: > > This set of patches introduces the usage of eBPF for packet steering > > and RSS hash calculation: > > * RSS(Receive Side Scaling) is used to distribute network packets to > > guest virtqueues by calculating packet hash > > * Additionally adding support for the usage of RSS with vhost > > > > The eBPF works on kernels 5.8+ > > On earlier kerneld it fails to load and the RSS feature is reported > > only without vhost and implemented in 'in-qemu' software. > > > > Implementation notes: > > Linux TAP TUNSETSTEERINGEBPF ioctl was used to set the eBPF program. > > Added libbpf dependency and eBPF support. > > The eBPF program is part of the qemu and presented as an array > > of BPF ELF file data. The eBPF array file initially generated by bpftool. > > The compilation of eBPF is not part of QEMU build and can be done > > using provided Makefile.ebpf. > > Added changes to virtio-net and vhost, primary eBPF RSS is used. > > 'in-qemu' RSS used in the case of hash population and as a fallback option. > > For vhost, the hash population feature is not reported to the guest. > > > > Please also see the documentation in PATCH 6/7. > > > > Known issues: > > * hash population not supported by eBPF RSS: 'in-qemu' RSS used > > as a fallback, also, hash population feature is not reported to guests > > with vhost. > > * IPv6 extensions still in progress. > > > Hi Andrew: > > The patch looks good at a glance. I tend to queue it for 6.1. > > One issue is that, there's no easy way for testing it without a windows > guest. > > Do you have plan to extend Linux driver to support RSS (e.g via ethtool?). > > Thanks > > > > > > Changes since v1: > > * using libbpf instead of direct 'bpf' system call. > > * added libbpf dependency to the configure/meson scripts. > > * changed python script for eBPF .h file generation. > > * changed eBPF program - reading L3 proto from ethernet frame. > > * added TUNSETSTEERINGEBPF define for TUN. > > * changed the maintainer's info. > > * added license headers. > > * refactored code. > > > > Changes since v2: > > * using bpftool for eBPF skeleton generation. > > * ebpf_rss is refactored to use skeleton generated by bpftool. > > * added/adjasted license in comment sections and in eBPF file. > > * rss.bpf.c and Makefile.ebpf moved to the tool/ebpf folder. > > * virtio-net eBPF rss refactored. Now eBPF initialized during realize(). > > > > Changes since v3: > > * rebased to last master. > > * fixed issue with failed build without libbpf. > > * fixed ebpf loading without rss option. > > * refactored labels in ebpf_rss.c > > > > Changes since v4: > > * refactored configure/meson script. > > * added checks for load_bytes in ebpf. > > * documentation added to the index. > > * refactored Makefile and rss.bpf.c. > > * rebased to last master. > > > > Andrew (7): > > net/tap: Added TUNSETSTEERINGEBPF code. > > net: Added SetSteeringEBPF method for NetClientState. > > ebpf: Added eBPF RSS program. > > ebpf: Added eBPF RSS loader. > > virtio-net: Added eBPF RSS to virtio-net. > > docs: Added eBPF documentation. > > MAINTAINERS: Added eBPF maintainers information. > > > > MAINTAINERS | 8 + > > configure | 8 +- > > docs/devel/ebpf_rss.rst | 125 ++++++++ > > docs/devel/index.rst | 1 + > > ebpf/ebpf_rss-stub.c | 40 +++ > > ebpf/ebpf_rss.c | 165 ++++++++++ > > ebpf/ebpf_rss.h | 44 +++ > > ebpf/meson.build | 1 + > > ebpf/rss.bpf.skeleton.h | 423 +++++++++++++++++++++++++ > > ebpf/trace-events | 4 + > > ebpf/trace.h | 2 + > > hw/net/vhost_net.c | 3 + > > hw/net/virtio-net.c | 115 ++++++- > > include/hw/virtio/virtio-net.h | 4 + > > include/net/net.h | 2 + > > meson.build | 9 + > > meson_options.txt | 2 + > > net/tap-bsd.c | 5 + > > net/tap-linux.c | 13 + > > net/tap-linux.h | 1 + > > net/tap-solaris.c | 5 + > > net/tap-stub.c | 5 + > > net/tap.c | 9 + > > net/tap_int.h | 1 + > > net/vhost-vdpa.c | 2 + > > tools/ebpf/Makefile.ebpf | 22 ++ > > tools/ebpf/rss.bpf.c | 552 +++++++++++++++++++++++++++++++++ > > 27 files changed, 1567 insertions(+), 4 deletions(-) > > create mode 100644 docs/devel/ebpf_rss.rst > > create mode 100644 ebpf/ebpf_rss-stub.c > > create mode 100644 ebpf/ebpf_rss.c > > create mode 100644 ebpf/ebpf_rss.h > > create mode 100644 ebpf/meson.build > > create mode 100644 ebpf/rss.bpf.skeleton.h > > create mode 100644 ebpf/trace-events > > create mode 100644 ebpf/trace.h > > create mode 100755 tools/ebpf/Makefile.ebpf > > create mode 100644 tools/ebpf/rss.bpf.c > > >
