Re: [PATCH 04/12] perf: add @rq to perf_event_task_sched_out()

Steven Rostedt
2010-05-04T18:32:14Z

On Tue, 2010-05-04 at 20:26 +0200, Peter Zijlstra wrote:
> On Tue, 2010-05-04 at 14:22 -0400, Steven Rostedt wrote:
> > On Tue, 2010-05-04 at 19:22 +0200, Tejun Heo wrote:
> > > Hello,
> > >
> > > On 05/04/2010 07:11 PM, Peter Zijlstra wrote:
> > > > On Tue, 2010-05-04 at 14:38 +0200, Tejun Heo wrote:
> > > >> Add @rq to perf_event_task_sched_out() so that its argument matches
> > > >> those of trace_sched_switch(). This will help unifying notifiers in
> > > >> sched.
> > > >
> > > > The alternative is dropping rq from the trace events, its not like
> > > > anybody outside sched.o can do anything sensible with it anyway.
> > >
> > > The comment in include/trace/events/sched.h says...
> > >
> > > * (NOTE: the 'rq' argument is not used by generic trace events,
> > > * but used by the latency tracer plugin. )
> > >
> > > So, I left it there. It would be great if all those @rq params can be
> > > removed tho. The latency tracer thing needs it, right?
> >
> > I believe the rq was used by the original latency tracer code that was
> > in the -rt patch set before ftrace. It is most likely there for
> > historical purposes. I guess it would be fine to just remove it.
>
> I'm building the below, so far so good... ;-)
>
> ---
> include/trace/events/sched.h | 32 ++++++++++----------------------
> kernel/sched.c | 8 ++++----
> kernel/trace/trace_sched_wakeup.c | 5 ++---
> 3 files changed, 16 insertions(+), 29 deletions(-)
>
> diff --git a/include/trace/events/sched.h b/include/trace/events/sched.h
> index cfceb0b..4f733ec 100644
> --- a/include/trace/events/sched.h
> +++ b/include/trace/events/sched.h
> @@ -51,15 +51,12 @@ TRACE_EVENT(sched_kthread_stop_ret,
>
> /*
> * Tracepoint for waiting on task to unschedule:
> - *
> - * (NOTE: the 'rq' argument is not used by generic trace events,
> - * but used by the latency tracer plugin. )
> */
> TRACE_EVENT(sched_wait_task,
>
> - TP_PROTO(struct rq *rq, struct task_struct *p),
> + TP_PROTO(struct task_struct *p),

Acked-by: Steven Rostedt <rostedt@goodmis.org>

-- Steve