[dpdk-dev] Direct using of 'rte_eth_devices' in DPDK apps.

[Ilya Maximets <i.maximets@samsung.com>]

Hi,
While discussing the ways to enable DPDK 18.11 new features in OVS
there was suggestions to use 'rte_eth_devices[]' array directly.
But this array is marked as '@internal' and also it located in
the internal header 'lib/librte_ethdev/rte_ethdev_core.h' with the
following disclaimer:

/**
 * @file
 *
 * RTE Ethernet Device internal header.
 *
 * This header contains internal data types. But they are still part of the
 * public API because they are used by inline functions in the published API.
 *
 * Applications should not use these directly.
 *
 */

>From the other hand, test-pmd and some example apps in DPDK source
tree are using this array for various reasons.

So, is it OK to use this array directly or not?

In general we need to change the API, i.e. make 'rte_eth_devices' part
of a public API. Or change the test-pmd and example apps to stop
using it.

One more related question: Is it OK to access internal device
stuff using 'device' pointer obtained by 'rte_eth_dev_info'?
This looks really dangerous. It's unclear why pointers like this
exposed to user.

Thoughts?

Best regards, Ilya Maximets.