[xdp-hints] Re: [PATCH bpf V6 5/5] selftests/bpf: Adjust bpf_xdp_metadata_rx_hash for new arg

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

On Sun, Apr 2, 2023 at 1:30 AM Jesper Dangaard Brouer <brouer@redhat.com> wrote:
>
> Update BPF selftests to use the new RSS type argument for kfunc
> bpf_xdp_metadata_rx_hash.
>
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
> Acked-by: Stanislav Fomichev <sdf@google.com>
> ---
>  .../selftests/bpf/prog_tests/xdp_metadata.c        |    2 ++
>  .../testing/selftests/bpf/progs/xdp_hw_metadata.c  |   14 +++++++++-----
>  tools/testing/selftests/bpf/progs/xdp_metadata.c   |    6 +++---
>  tools/testing/selftests/bpf/progs/xdp_metadata2.c  |    7 ++++---
>  tools/testing/selftests/bpf/xdp_hw_metadata.c      |    2 +-
>  tools/testing/selftests/bpf/xdp_metadata.h         |    1 +
>  6 files changed, 20 insertions(+), 12 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c b/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
> index aa4beae99f4f..8c5e98da9ae9 100644
> --- a/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
> +++ b/tools/testing/selftests/bpf/prog_tests/xdp_metadata.c
> @@ -273,6 +273,8 @@ static int verify_xsk_metadata(struct xsk *xsk)
>         if (!ASSERT_NEQ(meta->rx_hash, 0, "rx_hash"))
>                 return -1;
>
> +       ASSERT_EQ(meta->rx_hash_type, 0, "rx_hash_type");
> +
>         xsk_ring_cons__release(&xsk->rx, 1);
>         refill_rx(xsk, comp_addr);
>
> diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> index 4c55b4d79d3d..7b3fc12e96d6 100644
> --- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> +++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> @@ -14,8 +14,8 @@ struct {
>
>  extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
>                                          __u64 *timestamp) __ksym;
> -extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx,
> -                                   __u32 *hash) __ksym;
> +extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
> +                                   enum xdp_rss_hash_type *rss_type) __ksym;
>
>  SEC("xdp")
>  int rx(struct xdp_md *ctx)
> @@ -74,10 +74,14 @@ int rx(struct xdp_md *ctx)
>         else
>                 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
> +       if (!bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash, &meta->rx_hash_type)) {
> +               bpf_printk("populated rx_hash:0x%X type:0x%X",
> +                          meta->rx_hash, meta->rx_hash_type);
> +               if (!(meta->rx_hash_type & XDP_RSS_L4))
> +                       bpf_printk("rx_hash low quality L3 hash type");
> +       } else {
>                 meta->rx_hash = 0; /* Used by AF_XDP as not avail signal */
> +       }

Didn't we agree in the previous thread to remove these printks and
replace them with actual stats that user space can see?