[xdp-hints] Re: [PATCH bpf-next V3 3/6] selftests/bpf: xdp_hw_metadata RX hash return code info

[Alexei Starovoitov <alexei.starovoitov@gmail.com>]

On Wed, Mar 22, 2023 at 9:01 AM Jesper Dangaard Brouer
<brouer@redhat.com> wrote:
>
> When driver developers add XDP-hints kfuncs for RX hash it is
> practical to print the return code in bpf_printk trace pipe log.
>
> Print hash value as a hex value, both AF_XDP userspace and bpf_prog,
> as this makes it easier to spot poor quality hashes.
>
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
> Acked-by: Stanislav Fomichev <sdf@google.com>
> ---
>  .../testing/selftests/bpf/progs/xdp_hw_metadata.c  |    9 ++++++---
>  tools/testing/selftests/bpf/xdp_hw_metadata.c      |    5 ++++-
>  2 files changed, 10 insertions(+), 4 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> index 40c17adbf483..ce07010e4d48 100644
> --- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> +++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> @@ -77,10 +77,13 @@ int rx(struct xdp_md *ctx)
>                 meta->rx_timestamp = 0; /* Used by AF_XDP as not avail signal */
>         }
>
> -       if (!bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash))
> -               bpf_printk("populated rx_hash with %u", meta->rx_hash);
> -       else
> +       ret = bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash);
> +       if (ret >= 0) {
> +               bpf_printk("populated rx_hash with 0x%08X", meta->rx_hash);
> +       } else {
> +               bpf_printk("rx_hash not-avail errno:%d", ret);
>                 meta->rx_hash = 0; /* Used by AF_XDP as not avail signal */
> +       }

Just noticed this mess of printks.
Please remove them all. selftests should not have them.