[dpdk-dev] [RFC] ethdev: complete closing to free all resources

[Andrew Rybchenko]

On 09/10/2018 11:42 AM, Thomas Monjalon wrote:
> 10/09/2018 10:03, Andrew Rybchenko:
>> On 09/08/2018 02:39 AM, Thomas Monjalon wrote:
>>> After closing a port, it cannot be restarted.
>>> So there is no reason to not free all associated resources.
>>>
>>> The last step was done with rte_eth_dev_detach() which is deprecated.
>>> Instead of removing the associated rte_device, the driver should check
>>> if no more port (ethdev, cryptodev, etc) is still open for the device.
>>> Then the device resources can be freed by the driver inside the
>>> dev_close() driver callback operation.
>>>
>>> The last ethdev freeing (dev_private and final release), which were done
>>> by rte_eth_dev_detach(), are now done at the end of rte_eth_dev_close().
>> For me, it sounds more logical to kill dev_close and keep detach.
>> IMHO, dev_close is artificial and hardly useful. detach is a local pair
>> to attach.
> I don't get your point.
>
> In order to free a port, we need close + detach.
> We can keep only one.
> I choose close because:
> 	1) attach/detach are deprecated
> 	2) probe/close is a more obvious pair
> 	3) we need the driver to free the lower level resources

Yes, I'm sorry I used bad terminology.
We have probe/remove pair for both PCI and vdev drivers and I mean
that remove is a better candidate to be kept (as a pair for probe which
allocates all resources).