Re: [dpdk-dev] [PATCH v4] net/ice: add flow mark hint support

[Thomas Monjalon <thomas@monjalon.net>]

19/11/2019 07:14, Qi Zhang:
> Since not all data paths support flow mark, the driver needs
> a hint from application to select the correct data path if
> flow mark is required. The patch introduces a devarg
> "flow-mark-support" as a workaround solution, since a standard
> way is still ongoing.
> 
> Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
> Acked-by: Qiming Yang <qiming.yang@intel.com>
> ---
> 
> v4:
> - remove debug code, fix typos
> 
> v3:
> - add "experimental notification" in ice.rst
> 
> v2:
> - fix typos

Please use --in-reply-to to help tracking all the versions together.

> +- ``Flow Mark Support`` (default ``0``)
> +
> +  This is a hint to the driver to select the data path that supports flow mark extraction
> +  by default.
> +  NOTE: This is an experimental devarg, it will be removed when any of below conditions
> +  is ready.
> +  1) all data paths support flow mark (currently vPMD does not)
> +  2) a new offload like RTE_DEV_RX_OFFLOAD_FLOW_MARK be introduced as a standard way to hint.

When the data path is selected?
I suppose such decision should be done when starting the port,
after everything is configured.
So you can check if a rte_flow rule was added for mark action.
Why the user needs to use an explicit option?