Re: [PATCH] sched/debug:fix stale comments of sched_debug

[Hailong Liu]

On 6/1/21 8:58 PM, Andy Shevchenko wrote:
> On Tue, Jun 01, 2021 at 09:56:51AM +0200, Peter Zijlstra wrote:
>> On Mon, May 31, 2021 at 07:05:22PM +0300, Andy Shevchenko wrote:
>>>>>> --- a/lib/Kconfig.debug
>>>>>> +++ b/lib/Kconfig.debug
>>>>>> @@ -1166,7 +1166,7 @@ config SCHED_DEBUG
>>>>>>  	depends on DEBUG_KERNEL && PROC_FS
>>>>>
>>>>> Are the dependencies correct?
>>>>
>>>> Based on your suggestion, I checked and it turned out that PROC_FS is not
>>>> the correct dependency, but DEBUG_FS. 
>>>
>>> I guess you missed something.
>>>
>>>> Shoud I change it to DEBUG_FS?
>>>
>>> Please, double check.
>>
>> Thing is that proc_sched_show_task() still wants PROC_FS, i've not yet
>> found a suitable debugfs based location for that.
>>
>> And DEBUG_FS doesn't need a dependency; it has complete DEBUG_FS=n
>> wrappers and will build fine. Arguably selecting SCHED_DEBUG without
>> DEBUG_FS is daft, but it should work.
> 
> Yep, my point here is that we have several files (in procfs and debugfs) which
> are enabled by the same option. Changing help text as it's done in the patch
> seems a half baked solution, i.e. it needs more, like describing what the files
> are visible in different configurations.
> 

Big thanks to Andy and Peter for the views and suggestions.

Personally, neither DEBUG_FS nor RPOC_FS are the building dependencies of
SCHED_DEBUG. However, The visibility of the files(in procfs and debugfs) depends
on both.

So, can I make a compromise and add both PROC_FS and DEBUG_FS as dependencies in
Kconfig; at the same time, add more descriptions of the two situations in the
help text?