[dpdk-dev] [PATCH 1/2] ethdev: add symmetric toeplitz hash support

[Andrew Rybchenko]

On 7/25/19 7:57 AM, simei wrote:
> From: Simei Su <simei.su at intel.com>
> 
> Currently, there are DEFAULT,TOEPLITZ and SIMPLE_XOR hash funtion.
> To support symmetric hash by rte_flow RSS action, this patch adds
> new hash function "Symmetric Toeplitz" which is supported by some hardware.

Isn't it a question of key to achieve symmetry?
I.e. hash algorithm (function) is still the same - Toeplitz, but
hash key makes the result symmetric (i.e. equal for flows in both
directions - swap transport ports and IPv4/6 addresses).

> Signed-off-by: Simei Su <simei.su at intel.com>
> ---
>   lib/librte_ethdev/rte_flow.h | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/lib/librte_ethdev/rte_flow.h b/lib/librte_ethdev/rte_flow.h
> index f3a8fb1..2a0e6d5 100644
> --- a/lib/librte_ethdev/rte_flow.h
> +++ b/lib/librte_ethdev/rte_flow.h
> @@ -1744,6 +1744,7 @@ enum rte_eth_hash_function {
>   	RTE_ETH_HASH_FUNCTION_DEFAULT = 0,
>   	RTE_ETH_HASH_FUNCTION_TOEPLITZ, /**< Toeplitz */
>   	RTE_ETH_HASH_FUNCTION_SIMPLE_XOR, /**< Simple XOR */
> +	RTE_ETH_HASH_FUNCTION_SYMMETRIC_TOEPLITZ, /**< Symmetric Toeplitz */
>   	RTE_ETH_HASH_FUNCTION_MAX,
>   };
>   
>