[PATCH] ethdev: add new symmetric hash function

[Ivan Malov]

Hi,

Please see my notes below.

On Mon, 7 Aug 2023, Xueming Li wrote:

> The new symmetric hash function swap src/dst L3 address and
> L4 ports automatically by sorting.
>
> Signed-off-by: Xueming Li <xuemingl at nvidia.com>
> ---
> lib/ethdev/rte_flow.h | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h
> index 86ed98c562..ec6dd170b5 100644
> --- a/lib/ethdev/rte_flow.h
> +++ b/lib/ethdev/rte_flow.h
> @@ -3204,6 +3204,11 @@ enum rte_eth_hash_function {
> 	 * src or dst address will xor with zero pair.
> 	 */
> 	RTE_ETH_HASH_FUNCTION_SYMMETRIC_TOEPLITZ,
> +	/**
> +	 * Symmetric Toeplitz: src, dst will be swapped
> +	 * automatically by sorting.

This is very vague. Consider:

For symmetric Toeplitz, four inputs are prepared as follows:
- src_addr | dst_addr
- src_addr ^ dst_addr
- src_port | dst_port
- src_port ^ dst_port
and then passed to the regular Toeplitz function.

It is important to be as specific as possible
so that readers don't have to guess.

Thank you.

> +	 */
> +	RTE_ETH_HASH_FUNCTION_SYMMETRIC_TOEPLITZ_SORT,
> 	RTE_ETH_HASH_FUNCTION_MAX,
> };
>
> -- 
> 2.25.1
>
>