Re: [PATCH] rcu: convert rcupreempt trace to seq file

Li Zefan
2009-01-12T01:10:04Z

>> The debugfs and seqfile handling and handled in the statistical
>> tracing engine.
>>
>> You just have to provide an iterator for your stat entries through two callbacks:
>>
>> _ stat_start() -> gives the first entry
>> _ stat_next() -> iterates over the next entry
>>
>> And an output callback
>>
>> _ stat_show() -> print one entry from your stat list
>>
>> And two optional things:
>>
>> _ stat_cmp() -> compare two entries, useful if you want your stats to be sorted
>> _ stat_headers() -> provide the first line in your stat file, typically to describe your columns
>>
>> The last thing you need is to give a name to your trace file.
>> You will retrieve it into /debugfs/tracing/trace_stat/your_file_name as a current snapshot
>> of your stats.
>>
>> It is currently used by the branch tracer, and by a pending patch for a new workqueue
>> tracer which will provide you a simple example.
>>
>> If you have any question about how to use it, don't hesitate to ask.
>
> Li Zefan, is this something you would be willing to try? Sounds like
> it might be a good addition.
>

Sure, I'll try. :)