[xdp-hints] Re: [PATCH bpf V7 4/7] mlx5: bpf_xdp_metadata_rx_hash add xdp rss hash type

[Simon Horman <simon.horman@corigine.com>]

On Sat, Apr 08, 2023 at 09:24:56PM +0200, Jesper Dangaard Brouer wrote:
> Update API for bpf_xdp_metadata_rx_hash() with arg for xdp rss hash type
> via mapping table.
> 
> The mlx5 hardware can also identify and RSS hash IPSEC.  This indicate
> hash includes SPI (Security Parameters Index) as part of IPSEC hash.
> 
> Extend xdp core enum xdp_rss_hash_type with IPSEC hash type.
> 
> Fixes: bc8d405b1ba9 ("net/mlx5e: Support RX XDP metadata")
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
> Acked-by: Stanislav Fomichev <sdf@google.com>
> ---
>  drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c |   60 ++++++++++++++++++++++
>  include/linux/mlx5/device.h                      |   14 ++++-
>  include/net/xdp.h                                |    2 +
>  3 files changed, 73 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
> index efe609f8e3aa..97ef1df94d50 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
> @@ -34,6 +34,7 @@
>  #include <net/xdp_sock_drv.h>
>  #include "en/xdp.h"
>  #include "en/params.h"
> +#include <linux/bitfield.h>
>  
>  int mlx5e_xdp_max_mtu(struct mlx5e_params *params, struct mlx5e_xsk_param *xsk)
>  {
> @@ -169,15 +170,72 @@ static int mlx5e_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp)
>  	return 0;
>  }
>  
> +/* Mapping HW RSS Type bits CQE_RSS_HTYPE_IP + CQE_RSS_HTYPE_L4 into 4-bits*/
> +#define RSS_TYPE_MAX_TABLE	16 /* 4-bits max 16 entries */
> +#define RSS_L4		GENMASK(1, 0)
> +#define RSS_L3		GENMASK(3, 2) /* Same as CQE_RSS_HTYPE_IP */
> +
> +/* Valid combinations of CQE_RSS_HTYPE_IP + CQE_RSS_HTYPE_L4 sorted numerical */
> +enum mlx5_rss_hash_type {
> +	RSS_TYPE_NO_HASH	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IP_NONE) |
> +				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
> +	RSS_TYPE_L3_IPV4	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
> +				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
> +	RSS_TYPE_L4_IPV4_TCP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
> +				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_TCP)),
> +	RSS_TYPE_L4_IPV4_UDP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
> +				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_UDP)),
> +	RSS_TYPE_L4_IPV4_IPSEC	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
> +				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_IPSEC)),
> +	RSS_TYPE_L3_IPV6	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
> +				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
> +	RSS_TYPE_L4_IPV6_TCP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
> +				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_TCP)),
> +	RSS_TYPE_L4_IPV6_UDP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
> +				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_UDP)),
> +	RSS_TYPE_L4_IPV6_IPSEC	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
> +				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_IPSEC)),
> +} mlx5_rss_hash_type;

Hi Jesper,

Sparse seems confused about 'mlx5_rss_hash_type' on the line above.
And I am too. Perhaps it can be removed?

drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c:198:3: warning: symbol 'mlx5_rss_hash_type' was not declared. Should it be static?

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