Re: [dpdk-dev] [PATCH] app/testpmd: fix hotplug

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 1/23/2020 5:46 PM, Iremonger, Bernard wrote:
> Hi Ferruh,
> 
>> <snip>
>>
>>>>> Subject: [PATCH] app/testpmd: fix hotplug
>>>>>
>>>> This is reverting the original patch, which breaks hotplug.
>>>> I think the commit message should make this clear.
>>>> This patch is not fixing hotplug, the original patch seems to have
>>>> revealed a
>>> problem with hotplug.
>>>> Reverting this patch will not fix the underlying hotplug issue.
>>>
>>> What is the problem revealed by the original patch? Did you able to
>>> reproduce it?
>>
>> No, I thought you had.

I can't reproduce the problem mentioned in original patch, but can reproduce
now, so from my perspective "fixing testpmd hotplug"

>> There is a lot of information in the commit message, but is not clear that you
>> are reverting a patch.

OK I can add a note

>> I am ok with reverting the original patch as it has caused a problem.
> 
> Just had another look at the patch, there are two changes.
> One reverts the original patch.
> The second is a fix.

Not exactly, fix is reverting, second change is removing log which is to reduce
the noise.
Both changes mentioned in the commit log.

> Suggest splitting patch into two, one for revert and second one for fix.
> 
>>
>>>
>>>>
>>>>> The 'port_id_is_invalid()' check in the 'detach_port_device()' is
>>>>> breaking the hotplug support, since at that stage port will be
>>>>> closed and validity check always fail [1] and removing the device
>>>>> is not really
>>> completed.
>>>>>
>>>>> But this cause the vfio request interrupt keep triggered
>>>>> continuously and makes the application unusable, since port is
>>>>> closed but device is not removed, the remove path keep generating
>> error log:
>>>>>
>>>>> EAL: can not get port by device 0000:00:05.0!
>>>>> EAL: can not get port by device 0000:00:05.0!
>>>>> EAL: can not get port by device 0000:00:05.0!
>>>>> EAL: can not get port by device 0000:00:05.0!
>>>>> EAL: can not get port by device 0000:00:05.0!
>>>>> EAL: can not get port by device 0000:00:05.0!
>>>>>
>>>>> Fixed by removing 'port_id_is_invalid()' check from
>>>>> 'detach_port_device()', anyway it shouldn't be required. Without
>>>>> this check device remove works as expected.
>>>>>
>>>>> Only "Invalid port_id=0" logs seen a few times, which is because
>>>>> the actual removal not done synchronously but an alarm set for it,
>>>>> until the alarm fired application may receive many interrupts,
>>>>> expect the first ones cause the error.
>>>>> So this patch also removes the logging from checking the invalid
>>>>> port in 'rmv_port_callback()' to reduce the noise.
>>>>>
>>>>> [1]
>>>>> rmv_port_callback()
>>>>>   stop_port(port_id);
>>>>>   close_port(port_id);
>>>>>   detach_port_device(port_id);
>>>>>
>>>>> Fixes: 43d0e304980a ("app/testpmd: fix invalid port detaching")
>>>>> Cc: stable@dpdk.org
>>>>>
>>>>> Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
>>>>> ---
>>>>>  app/test-pmd/testpmd.c | 6 ++----
>>>>>  1 file changed, 2 insertions(+), 4 deletions(-)
>>>>>
>>>>> diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c index
>>>>> f9f4cd1d3..3323013bb 100644
>>>>> --- a/app/test-pmd/testpmd.c
>>>>> +++ b/app/test-pmd/testpmd.c
>>>>> @@ -2641,9 +2641,6 @@ detach_port_device(portid_t port_id)
>>>>>
>>>>>  printf("Removing a device...\n");
>>>>>
>>>>> -if (port_id_is_invalid(port_id, ENABLED_WARN)) -return;
>>>>> -
>>>>>  dev = rte_eth_devices[port_id].device;  if (dev == NULL) {
>>>>> printf("Device already removed\n"); @@ -2875,7 +2872,8 @@
>>>>> rmv_port_callback(void *arg)  int org_no_link_check =
>>>>> no_link_check; portid_t port_id = (intptr_t)arg;
>>>>>
>>>>> -RTE_ETH_VALID_PORTID_OR_RET(port_id);
>>>>> +if (!rte_eth_dev_is_valid_port(port_id))
>>>>> +return;
>>>>>
>>>>>  if (!test_done && port_is_forwarding(port_id)) {  need_to_start =
>>>>> 1;
>>>>> --
>>>>> 2.24.1
>>>>
>>>> Otherwise
>>>> Acked-by: Bernard Iremonger <bernard.iremonger@intel.com>
>>>>
>  Regards,
> 
>  Bernard.
>