[PATCH] app/testpmd: support retrying device stop

[Ferruh Yigit]

On 6/3/2024 6:09 PM, Stephen Hemminger wrote:
> On Sun, 2 Jun 2024 13:30:35 +0300
> Maayan Kashani <mkashani at nvidia.com> wrote:
> 
>> From: Dariusz Sosnowski <dsosnowski at nvidia.com>
>>
>> In some cases rte_eth_dev_stop() can fail with EBUSY error code meaning
>> that port cannot be stopped, because of other resources referencing this
>> port and port must be stopped again after these resources are freed.
>>
>> This patch adds handling of EBUSY error code on port stop to testpmd.
>>
>> Signed-off-by: Dariusz Sosnowski <dsosnowski at nvidia.com>
> 
> What causes EBUSY. Seems like a driver bug or a test scenario problem.
> You can't expect every DPDK application to retry.
>

'rte_eth_dev_stop()' returning EBUSY anticipates this kind of usage already.

But I also agree we should avoid propagating driver issues to the
application, that is why it is better to clarify motivation of this
patch, why specific driver returns EBUSY on stop.