[xdp-hints] Re: [PATCH bpf-next v2 8/8] selftests/bpf: Simple program to dump XDP RX metadata

[Stanislav Fomichev <sdf@google.com>]

On Wed, Nov 23, 2022 at 6:26 AM Toke Høiland-Jørgensen <toke@redhat.com> wrote:
>
> Stanislav Fomichev <sdf@google.com> writes:
>
> > +static int rxq_num(const char *ifname)
> > +{
> > +     struct ethtool_channels ch = {
> > +             .cmd = ETHTOOL_GCHANNELS,
> > +     };
> > +
> > +     struct ifreq ifr = {
> > +             .ifr_data = (void *)&ch,
> > +     };
> > +     strcpy(ifr.ifr_name, ifname);
> > +     int fd, ret;
> > +
> > +     fd = socket(AF_UNIX, SOCK_DGRAM, 0);
> > +     if (fd < 0)
> > +             error(-1, errno, "socket");
> > +
> > +     ret = ioctl(fd, SIOCETHTOOL, &ifr);
> > +     if (ret < 0)
> > +             error(-1, errno, "socket");
> > +
> > +     close(fd);
> > +
> > +     return ch.rx_count;
> > +}
>
> mlx5 uses 'combined' channels, so this returns 0. Changing it to just:
>
> return ch.rx_count ?: ch.combined_count;
>
> works though :)

Perfect, will do the same :-) Thank you for running and testing!

> -Toke
>