Re: [dpdk-dev] [PATCH v3 4/4] ethdev: check driver support for functions

[Stephen Hemminger <stephen@networkplumber.org>]

On Tue,  3 Nov 2015 12:00:59 +0000
Bruce Richardson <bruce.richardson@intel.com> wrote:

>  * @return
> - *  The number of used descriptors in the specific queue.
> + *  The number of used descriptors in the specific queue, or:
> + *     (-EINVAL) if *port_id* is invalid
> + *     (-ENOTSUP) if the device does not support this function
>   */
> -static inline uint32_t
> +static inline int
>  rte_eth_rx_queue_count(uint8_t port_id, uint16_t queue_id)
>  {
>  	struct rte_eth_dev *dev = &rte_eth_devices[port_id];
>  #ifdef RTE_LIBRTE_ETHDEV_DEBUG
> -	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, 0);
> -	RTE_ETH_FPTR_OR_ERR_RET(*dev->dev_ops->rx_queue_count, 0);
> +	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);
>  #endif

I think it should always check validity of portid/queueid
the check is very brief.