lkml.org 
[lkml]   [2023]   [Oct]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    Subject[RFC PATCH v2 0/7] tun: Introduce virtio-net hashing feature
    Date
    virtio-net have two usage of hashes: one is RSS and another is hash
    reporting. Conventionally the hash calculation was done by the VMM.
    However, computing the hash after the queue was chosen defeats the
    purpose of RSS.

    Another approach is to use eBPF steering program. This approach has
    another downside: it cannot report the calculated hash due to the
    restrictive nature of eBPF.

    Extend the steering program feature by introducing a dedicated program
    type: BPF_PROG_TYPE_VNET_HASH. This program type is capable to report
    the hash value and the queue to use at the same time.

    This is a rewrite of a RFC patch series submitted by Yuri Benditovich that
    incorporates feedbacks for the series and V1 of this series:
    https://lore.kernel.org/lkml/20210112194143.1494-1-yuri.benditovich@daynix.com/

    QEMU patched to use this new feature is available at:
    https://github.com/daynix/qemu/tree/akihikodaki/bpf

    The QEMU patches will soon be submitted to the upstream as RFC too.

    V1 -> V2:
    Changed to introduce a new BPF program type.

    Akihiko Odaki (7):
    bpf: Introduce BPF_PROG_TYPE_VNET_HASH
    bpf: Add vnet_hash members to __sk_buff
    skbuff: Introduce SKB_EXT_TUN_VNET_HASH
    virtio_net: Add virtio_net_hdr_v1_hash_from_skb()
    tun: Support BPF_PROG_TYPE_VNET_HASH
    selftests/bpf: Test BPF_PROG_TYPE_VNET_HASH
    vhost_net: Support VIRTIO_NET_F_HASH_REPORT

    Documentation/bpf/bpf_prog_run.rst | 1 +
    Documentation/bpf/libbpf/program_types.rst | 2 +
    drivers/net/tun.c | 158 +++++--
    drivers/vhost/net.c | 16 +-
    include/linux/bpf_types.h | 2 +
    include/linux/filter.h | 7 +
    include/linux/skbuff.h | 10 +
    include/linux/virtio_net.h | 22 +
    include/uapi/linux/bpf.h | 5 +
    kernel/bpf/verifier.c | 6 +
    net/core/filter.c | 86 +++-
    net/core/skbuff.c | 3 +
    tools/include/uapi/linux/bpf.h | 5 +
    tools/lib/bpf/libbpf.c | 2 +
    tools/testing/selftests/bpf/config | 1 +
    tools/testing/selftests/bpf/config.aarch64 | 1 -
    .../selftests/bpf/prog_tests/vnet_hash.c | 385 ++++++++++++++++++
    tools/testing/selftests/bpf/progs/vnet_hash.c | 16 +
    18 files changed, 681 insertions(+), 47 deletions(-)
    create mode 100644 tools/testing/selftests/bpf/prog_tests/vnet_hash.c
    create mode 100644 tools/testing/selftests/bpf/progs/vnet_hash.c

    --
    2.42.0

    \
     
     \ /
      Last update: 2023-10-15 16:17    [W:2.605 / U:0.004 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site