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Re: [RFC][PATCH 05/11] sched: Add preempt argument to __schedule()

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On Tue, 29 Sep 2015 11:28:39 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> On Tue, 29 Sep 2015 11:28:30 +0200
> Peter Zijlstra <peterz@infradead.org> wrote:
> 
> > There is only a single PREEMPT_ACTIVE use in the regular __schedule()
> > path and that is to circumvent the task->state check. Since the code
> > setting PREEMPT_ACTIVE is the immediate caller of __schedule() we can
> > replace this with a function argument.
> > 
> > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > ---
> 
> Reviewed-by: Steven Rostedt <rostedt@goodmis.org>

I just want to note that this scared me at first, because __schedule()
can be traced by the function tracer that can also do a
preempt_enable() which would schedule if preemption was enabled. But it
looks as __schedule() is always called with preemption disabled, thus,
no worries.

-- Steve

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[RFC][PATCH 05/11] sched: Add preempt argument to __schedule() Peter Zijlstra <peterz@infradead.org> - 2015-09-29 11:50 +0200
  Re: [RFC][PATCH 05/11] sched: Add preempt argument to __schedule() Frederic Weisbecker <fweisbec@gmail.com> - 2015-09-29 15:20 +0200
  Re: [RFC][PATCH 05/11] sched: Add preempt argument to __schedule() Steven Rostedt <rostedt@goodmis.org> - 2015-09-29 17:30 +0200
    Re: [RFC][PATCH 05/11] sched: Add preempt argument to __schedule() Steven Rostedt <rostedt@goodmis.org> - 2015-09-29 17:40 +0200
      Re: [RFC][PATCH 05/11] sched: Add preempt argument to __schedule() Peter Zijlstra <peterz@infradead.org> - 2015-09-29 17:40 +0200

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