Re: [PATCH v3 0/6] eBPF RSS through QMP support.

[Jason Wang]

On Thu, Jun 15, 2023 at 6:29 AM Andrew Melnychenko <andrew@daynix.com> wrote:
>
> This series of patches provides the ability to retrieve eBPF program
> through qmp, so management application may load bpf blob with proper 
> capabilities.
> Now, virtio-net devices can accept eBPF programs and maps through properties
> as external file descriptors. Access to the eBPF map is direct through mmap()
> call, so it should not require additional capabilities to bpf* calls.
> eBPF file descriptors can be passed to QEMU from parent process or by unix
> socket with sendfd() qmp command.
>
> Possible solution for libvirt may look like this: 
> https://github.com/daynix/libvirt/tree/RSS_eBPF (WIP)
>
> Changes since v2:
>  * moved/refactored QMP command
>  * refactored virtio-net

I've queued this series, but a question left:

mmap() support for eBPF maps is not supported from day0, should we
fallback to syscall for the OS that doesn't support that?

Thanks

>
> Changes since v1:
>  * refactored virtio-net
>  * moved hunks for ebpf mmap()
>  * added qmp enum for eBPF id.
>
> Andrew Melnychenko (6):
>   ebpf: Added eBPF map update through mmap.
>   ebpf: Added eBPF initialization by fds.
>   virtio-net: Added property to load eBPF RSS with fds.
>   ebpf: Added declaration/initialization routines.
>   qmp: Added new command to retrieve eBPF blob.
>   ebpf: Updated eBPF program and skeleton.
>
>  ebpf/ebpf.c                    |   70 ++
>  ebpf/ebpf.h                    |   31 +
>  ebpf/ebpf_rss-stub.c           |    6 +
>  ebpf/ebpf_rss.c                |  150 +++-
>  ebpf/ebpf_rss.h                |   10 +
>  ebpf/meson.build               |    2 +-
>  ebpf/rss.bpf.skeleton.h        | 1469 ++++++++++++++++----------------
>  hw/net/virtio-net.c            |   55 +-
>  include/hw/virtio/virtio-net.h |    1 +
>  qapi/ebpf.json                 |   55 ++
>  qapi/meson.build               |    1 +
>  qapi/qapi-schema.json          |    1 +
>  tools/ebpf/rss.bpf.c           |    2 +-
>  13 files changed, 1093 insertions(+), 760 deletions(-)
>  create mode 100644 ebpf/ebpf.c
>  create mode 100644 ebpf/ebpf.h
>  create mode 100644 qapi/ebpf.json
>
> --
> 2.39.1
>