Re: [PATCH] app/testpmd: handle IEEE1588 init fail

[huangdengdui <huangdengdui@huawei.com>]

On 2024/4/9 10:50, Stephen Hemminger wrote:
> On Tue, 9 Apr 2024 10:06:01 +0800
> huangdengdui <huangdengdui@huawei.com> wrote:
> 
>> On 2024/4/8 16:45, Ferruh Yigit wrote:
>>> On 4/8/2024 6:52 AM, huangdengdui wrote:  
>>>>
>>>>
>>>> On 2024/4/6 0:44, Stephen Hemminger wrote:  
>>>>> On Sat, 30 Mar 2024 15:44:09 +0800
>>>>> Dengdui Huang <huangdengdui@huawei.com> wrote:
>>>>>  
>>>>>> When the port's timestamping function failed to initialize
>>>>>> (for example, the device does not support PTP), the packets
>>>>>> received by the hardware do not contain the timestamp.
>>>>>> In this case, IEEE1588 packet forwarding should not start.
>>>>>> This patch fix it.
>>>>>>
>>>>>> Plus, adding a failure message when failed to disable PTP.
>>>>>>
>>>>>> Fixes: a78040c990cb ("app/testpmd: update forward engine beginning")
>>>>>> Cc: stable@dpdk.org
>>>>>>
>>>>>> Signed-off-by: Dengdui Huang <huangdengdui@huawei.com>  
>>>>>
>>>>> Noticed that ieee1588 part is printing errors to stdout,
>>>>> but other parts of test-pmd are using stderr or TEST_PMD_LOG.
>>>>>
>>>>> It would be good to decide on one good way to handle this
>>>>> across all of testpmd.  
>>>>
>>>> Yeah, it's a bit of a mess. Is it better to use TEST_PMD_LOG?
>>>> But this is a test app, and modifying it seems unnecessary.
>>>> What should we do next?
>>>>  
>>>
>>> 'TESTPMD_LOG' exists and used in a few places, but still most of the
>>> logging done with 'printf/fprintf'.
>>>
>>> Agree to have an agreement what to use, document it, and stick to it.
>>>
>>>
>>> For some cases, like 'usage()' output (testpmd supported parameters), or
>>> cmdline prompt we always want to have output, so 'printf' suits well.
>>>
>>> Not sure where 'TESTPMD_LOG' is needed and what is the benefit. I don't
>>> remember many cases that I want to refine testpmd app level output.
>>> Maybe a case can be packet verbose output, but it also has its specific
>>> command to control it.
>>>
>>> So should we continue to 'printf/fprintf', is there any disadvantage to
>>> do so?  
>> OK, 'printf/fprintf' is really necessary. Am I to understand it as follows?
>>
>> 'TESTPMD_LOG' is more suitable for printing app runtime context logs,
>> such as initialization logs and uninstallation logs.
>>
>> 'printf' is suitable for normal interaction with the user, such as
>> show port info <port_id>
>>
>> When should we print to stderr?
> 
> Any Unix convention is that any error message should go to stderr.
> For test-pmd, using TESTPMD_LOG has benefits and problems.
> The benefit is following a convention across all the startup and error
> codes. And with the color log patches, errors are highlighted.
> 
> But the current way rte_log works, the testpmd stuff ends up going
> to syslog/journal which is not necessary and overly chatty.

That seems hard to unify. I don't have a better idea at the moment.
Do you have a better suggestion?