On Mon, Jun 05, 2023 at 04:44:28PM +0200, Maciej Fijalkowski wrote:
> From: Magnus Karlsson <magnus.karlsson@xxxxxxxxx>
>
> Add the first basic multi-buffer test that sends a stream of 9K
> packets and validates that they are received at the other end. In
> order to enable sending and receiving multi-buffer packets, code that
> sets the MTU is introduced as well as modifications to the XDP
> programs so that they signal that they are multi-buffer enabled.
>
> Signed-off-by: Magnus Karlsson <magnus.karlsson@xxxxxxxxx>
> ---
> tools/include/uapi/linux/if_xdp.h | 6 +
> tools/include/uapi/linux/netdev.h | 3 +-
> .../selftests/bpf/progs/xsk_xdp_progs.c | 4 +-
> tools/testing/selftests/bpf/xsk.c | 136 +++++++++++++++++-
> tools/testing/selftests/bpf/xsk.h | 2 +
> tools/testing/selftests/bpf/xskxceiver.c | 67 +++++++++
> tools/testing/selftests/bpf/xskxceiver.h | 6 +
> 7 files changed, 220 insertions(+), 4 deletions(-)
>
> diff --git a/tools/include/uapi/linux/if_xdp.h b/tools/include/uapi/linux/if_xdp.h
> index 80245f5b4dd7..73a47da885dc 100644
> --- a/tools/include/uapi/linux/if_xdp.h
> +++ b/tools/include/uapi/linux/if_xdp.h
> @@ -25,6 +25,12 @@
> * application.
> */
> #define XDP_USE_NEED_WAKEUP (1 << 3)
> +/* By setting this option, userspace application indicates that it can
> + * handle multiple descriptors per packet thus enabling xsk core to split
> + * multi-buffer XDP frames into multiple Rx descriptors. Without this set
> + * such frames will be dropped by xsk.
> + */
> +#define XDP_USE_SG (1 << 4)
>
> /* Flags for xsk_umem_config flags */
> #define XDP_UMEM_UNALIGNED_CHUNK_FLAG (1 << 0)
> diff --git a/tools/include/uapi/linux/netdev.h b/tools/include/uapi/linux/netdev.h
> index 639524b59930..c1e59bfbae41 100644
> --- a/tools/include/uapi/linux/netdev.h
> +++ b/tools/include/uapi/linux/netdev.h
> @@ -33,8 +33,9 @@ enum netdev_xdp_act {
> NETDEV_XDP_ACT_HW_OFFLOAD = 16,
> NETDEV_XDP_ACT_RX_SG = 32,
> NETDEV_XDP_ACT_NDO_XMIT_SG = 64,
> + NETDEV_XDP_ACT_ZC_SG = 128,
Hi Maciej,
a minor nit from my side: NETDEV_XDP_ACT_ZC_SG was not added to the kernel
doc a few lines further above
> - NETDEV_XDP_ACT_MASK = 127,
> + NETDEV_XDP_ACT_MASK = 255,
> };
