[dpdk-dev] Support for configuring MTU on i40e

[Tom Crugnale]

Hi,

I am trying to configure the MTU through rte_eth_dev_set_mtu() on an i40e interface and noticed that the function pointer inside of the rte_eth_dev struct for mtu_set is not populated from the i40e code.
It seems that the only API that will allow for restricting the MTU is to call rte_eth_dev_configure() with the max_rx_pkt_len field set appropriately inside of the passed rte_eth_conf structure.

This makes it a bit awkward from any code that is common for all NIC types, forcing the caller to fall back on rte_eth_dev_configure() when rte_eth_dev_set_mtu() returns -ENOTSUP.

Is there any reason why an implementation for setting the MTU isn't supported through the proper API here?

Thanks,
Tom