Re: [dpdk-dev] [PATCH v3] ethdev: add IPv4 and L4 checksum RSS offload types

[Jerin Jacob <jerinjacobk@gmail.com>]

On Tue, Jun 15, 2021 at 1:50 PM Alvin Zhang <alvinx.zhang@intel.com> wrote:
>
> This patch defines new RSS offload types for IPv4 and L4 checksum,
> which are required when users want to distribute packets based on the
> IPv4 or L4 checksum field.

What is the usecase for distribution based on L4/IPv4 checksum?
Is it something like HW has the feature so expose it or there is some
real use case for this application?



> For example "flow create 0 ingress pattern eth / ipv4 / end
> actions rss types ipv4-chksum end queues end / end", this flow
> causes all matching packets to be distributed to queues on
> basis of IPv4 checksum.
>
> Signed-off-by: Alvin Zhang <alvinx.zhang@intel.com>
> Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
> Acked-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
> ---
>
> v3: Add L4 checksum RSS offload type
> ---
>  app/test-pmd/cmdline.c  | 4 ++++
>  app/test-pmd/config.c   | 2 ++
>  lib/ethdev/rte_ethdev.h | 2 ++
>  3 files changed, 8 insertions(+)
>
> diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c
> index 0268b18..6148d84 100644
> --- a/app/test-pmd/cmdline.c
> +++ b/app/test-pmd/cmdline.c
> @@ -2254,6 +2254,10 @@ struct cmd_config_rss {
>                 rss_conf.rss_hf = ETH_RSS_ECPRI;
>         else if (!strcmp(res->value, "mpls"))
>                 rss_conf.rss_hf = ETH_RSS_MPLS;
> +       else if (!strcmp(res->value, "ipv4-chksum"))
> +               rss_conf.rss_hf = ETH_RSS_IPV4_CHKSUM;
> +       else if (!strcmp(res->value, "l4-chksum"))
> +               rss_conf.rss_hf = ETH_RSS_L4_CHKSUM;
>         else if (!strcmp(res->value, "none"))
>                 rss_conf.rss_hf = 0;
>         else if (!strcmp(res->value, "level-default")) {
> diff --git a/app/test-pmd/config.c b/app/test-pmd/config.c
> index 43c79b5..14968bf 100644
> --- a/app/test-pmd/config.c
> +++ b/app/test-pmd/config.c
> @@ -140,6 +140,8 @@
>         { "gtpu", ETH_RSS_GTPU },
>         { "ecpri", ETH_RSS_ECPRI },
>         { "mpls", ETH_RSS_MPLS },
> +       { "ipv4-chksum", ETH_RSS_IPV4_CHKSUM },
> +       { "l4-chksum", ETH_RSS_L4_CHKSUM },
>         { NULL, 0 },
>  };
>
> diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h
> index faf3bd9..1268729 100644
> --- a/lib/ethdev/rte_ethdev.h
> +++ b/lib/ethdev/rte_ethdev.h
> @@ -537,6 +537,8 @@ struct rte_eth_rss_conf {
>  #define ETH_RSS_PPPOE             (1ULL << 31)
>  #define ETH_RSS_ECPRI             (1ULL << 32)
>  #define ETH_RSS_MPLS              (1ULL << 33)
> +#define ETH_RSS_IPV4_CHKSUM       (1ULL << 34)
> +#define ETH_RSS_L4_CHKSUM         (1ULL << 35)
>
>  /*
>   * We use the following macros to combine with above ETH_RSS_* for
> --
> 1.8.3.1
>