On Wed, Apr 12, 2023 at 11:35 AM Jesper Dangaard Brouer
<brouer@xxxxxxxxxx> wrote:
>
> The tool xdp_hw_metadata can be used by driver developers
> implementing XDP-hints metadata kfuncs.
>
> Remove all bpf_printk calls, as the tool already transfers all the
> XDP-hints related information via metadata area to AF_XDP
> userspace process.
>
> Add counters for providing remaining information about failure and
> skipped packet events.
>
> Signed-off-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx>
Acked-by: Stanislav Fomichev <sdf@xxxxxxxxxx>
nit: maybe those ++ should be __sync_add_and_fetch instead? Then you
should be able to drop volatile..
> ---
> .../testing/selftests/bpf/progs/xdp_hw_metadata.c | 36 ++++++++++++--------
> tools/testing/selftests/bpf/xdp_hw_metadata.c | 4 ++
> 2 files changed, 24 insertions(+), 16 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> index 4c55b4d79d3d..8a042343cb0c 100644
> --- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> +++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> @@ -12,6 +12,10 @@ struct {
> __type(value, __u32);
> } xsk SEC(".maps");
>
> +volatile __u64 pkts_skip = 0;
> +volatile __u64 pkts_fail = 0;
> +volatile __u64 pkts_redir = 0;
> +
> 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,
> @@ -26,7 +30,7 @@ int rx(struct xdp_md *ctx)
> struct udphdr *udp = NULL;
> struct iphdr *iph = NULL;
> struct xdp_meta *meta;
> - int ret;
> + int err;
>
> data = (void *)(long)ctx->data;
> data_end = (void *)(long)ctx->data_end;
> @@ -46,17 +50,20 @@ int rx(struct xdp_md *ctx)
> udp = NULL;
> }
>
> - if (!udp)
> + if (!udp) {
> + pkts_skip++;
> return XDP_PASS;
> + }
>
> - if (udp->dest != bpf_htons(9091))
> + /* Forwarding UDP:9091 to AF_XDP */
> + if (udp->dest != bpf_htons(9091)) {
> + pkts_skip++;
> return XDP_PASS;
> + }
>
> - bpf_printk("forwarding UDP:9091 to AF_XDP");
> -
> - ret = bpf_xdp_adjust_meta(ctx, -(int)sizeof(struct xdp_meta));
> - if (ret != 0) {
> - bpf_printk("bpf_xdp_adjust_meta returned %d", ret);
> + err = bpf_xdp_adjust_meta(ctx, -(int)sizeof(struct xdp_meta));
> + if (err) {
> + pkts_fail++;
> return XDP_PASS;
> }
>
> @@ -65,20 +72,19 @@ int rx(struct xdp_md *ctx)
> meta = data_meta;
>
> if (meta + 1 > data) {
> - bpf_printk("bpf_xdp_adjust_meta doesn't appear to work");
> + pkts_fail++;
> return XDP_PASS;
> }
>
> - if (!bpf_xdp_metadata_rx_timestamp(ctx, &meta->rx_timestamp))
> - bpf_printk("populated rx_timestamp with %llu", meta->rx_timestamp);
> - else
> + err = bpf_xdp_metadata_rx_timestamp(ctx, &meta->rx_timestamp);
> + if (err)
> 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
> + err = bpf_xdp_metadata_rx_hash(ctx, &meta->rx_hash);
> + if (err)
> meta->rx_hash = 0; /* Used by AF_XDP as not avail signal */
>
> + pkts_redir++;
> return bpf_redirect_map(&xsk, ctx->rx_queue_index, XDP_PASS);
> }
>
> diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> index 1c8acb68b977..3b942ef7297b 100644
> --- a/tools/testing/selftests/bpf/xdp_hw_metadata.c
> +++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> @@ -212,7 +212,9 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd)
> while (true) {
> errno = 0;
> ret = poll(fds, rxq + 1, 1000);
> - printf("poll: %d (%d)\n", ret, errno);
> + printf("poll: %d (%d) skip=%llu fail=%llu redir=%llu\n",
> + ret, errno, bpf_obj->bss->pkts_skip,
> + bpf_obj->bss->pkts_fail, bpf_obj->bss->pkts_redir);
> if (ret < 0)
> break;
> if (ret == 0)
>
>
