Re: [dpdk-dev] [PATCH] log: do not drop debug logs at compile time

[Olivier Matz <olivier.matz@6wind.com>]

Hi Keith,

On 09/30/2016 05:48 PM, Wiles, Keith wrote:
>> On Sep 30, 2016, at 4:33 AM, Thomas Monjalon <thomas.monjalon@6wind.com> wrote:
>>
>> 2016-09-16 09:43, Olivier Matz:
>>> Today, all logs whose level is lower than INFO are dropped at
>>> compile-time. This prevents from enabling debug logs at runtime using
>>> --log-level=8.
>>>
>>> The rationale was to remove debug logs from the data path at
>>> compile-time, avoiding a test at run-time.
>>>
>>> This patch changes the behavior of RTE_LOG() to avoid the compile-time
>>> optimization, and introduces the RTE_LOG_DP() macro that has the same
>>> behavior than the previous RTE_LOG(), for the rare cases where debug
>>> logs are in the data path.
>>>
>>> So it is now possible to enable debug logs at run-time by just
>>> specifying --log-level=8. Some drivers still have special compile-time
>>> options to enable more debug log. Maintainers may consider to
>>> remove/reduce them.
>>>
>>> Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
>>
>> I think it is a good change.
>> However I'm not sure we should take it for 16.11 as it was sent late and
>> there is no review comment.
>> It is neither really a fix nor really a feature.
>> If there are some +1, and no opinions against, it will go in 16.11.
>> Note that some drivers would need some changes to fully benefit of
>> debug logs enabled at run-time.
> 
> Would this be easier to add a new LOG level instead say DEBUG_DATAPATH and then change the RTE_LOG to exclude the new log level?
> 
> 

The log levels are quite standard, I don't feel it would be very clear
to have a new level for that. It would also prevent to have different
log level inside data path.

Regards,
Olivier