Re: [PATCH v2 10/10] net/mlx5: add rate table capacity query API

[Stephen Hemminger <stephen@networkplumber.org>]

On Thu, 12 Mar 2026 16:05:35 +0100
Vincent Jardin <vjardin@free.fr> wrote:

> >   
> > > +	if (!rte_eth_dev_is_valid_port(port_id))
> > > +		return -ENODEV;  
> > 
> > Ditto checks for port_id should be at ethdev  
> 
> This function is a PMD-specific API declared in rte_pmd_mlx5.h, not an ethdev op.
>   application -> rte_pmd_mlx5_pp_rate_table_query() -> mlx5 internals
> 
> Therefore, the function must validate its own inputs:
>  - port_id validity (via rte_eth_dev_get_by_name() / rte_eth_dev_is_valid_port())
>  - info != NULL
> 
> Adding a generic ethdev op (ex eth_rate_table_query_t) for a concept
> only one driver supports would be over-engineering.  If other drivers later
> expose a similar rate table concept, that would be the time to factor out a
> generic ethdev API.

OK, but I have a different point view than most DPDK developers.
Allowing and having driver specific API's in the first place was a mistake.
It encourages one off API's and makes applications locked in to a specific
NIC; which is good for NIC vendors but bad design pattern.