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

Paul E. McKenney
2009-01-12T02:00:10Z

On Mon, Jan 12, 2009 at 09:09:02AM +0800, Li Zefan wrote:
> >> 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. :)

Very cool! I look forward to seeing it!!!

Thanx, Paul