Re: [dpdk-stable] [dpdk-dev] [PATCH v2] app/testpmd: fix pmd_test_exit function for vdevs

[Thomas Monjalon <thomas@monjalon.net>]

19/05/2018 16:19, Thomas Monjalon:
> 18/05/2018 18:29, Ferruh Yigit:
> > On 5/18/2018 4:55 PM, Matan Azrad wrote:
> > > Hi all
> > > 
> > > While this patch also applied I don't understand it.
> > > Is it mandatory for each PMD to free all its resources in dev_close()?
> > > Or it should be done by the rte_device remove function?
> > > 
> > > If the resource cleanup should be done by the remove function I think it
> > > should be called for all the devices (pci, vdev, etc).
> > > 
> > > Is there an exit function for EAL to clean rte_eal_init()? If no, looks like we need it...
> > 
> > Hi Matan,
> > 
> > I believe there is a gap in resource cleanup.
> > dev_close() it not for resource cleanup, it should be in PMD remove() functions,
> > and PMDs have it. The problem is remove path is not called in application exit.
> > 
> > As far as I know there is no simple API to clean the resources, having it may
> > help application to do the cleanup.
> > 
> > I have seen the rte_eal_cleanup() API by Harry, that can be extended to cover
> > PMD resource cleanup if there is enough motivation for it.
> 
> Yes, EAL resources should be removed by the function rte_eal_cleanup().
> And ethdev ports must be removed by rte_eth_dev_close().

This patch is relying on rte_eth_dev_detach() to remove the EAL device.
It should be done in rte_eal_cleanup().

I am concerned that this patch is workarounding a miss in rte_eal_cleanup,
and takes a different action only for vdev. It is a bad example.

And the function rte_eth_dev_detach() is fundamentally wrong and should be deprecated:
	http://dpdk.org/commit/b05b444d22
	http://dpdk.org/commit/b0fb266855
	http://dpdk.org/commit/df3e8ad73f

One more concern: it seems this patch is breaking failsafe use case.
Note: bonding is managed as an exception in rte_eth_dev_detach().