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

[huangdengdui <huangdengdui@huawei.com>]

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?