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Date: Tue, 29 Sep 2015 17:46:27 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: mingo@kernel.org, linux-kernel@vger.kernel.org,
        torvalds@linux-foundation.org, fweisbec@gmail.com, oleg@redhat.com,
        umgwanakikbuti@gmail.com, tglx@linutronix.de
Subject: Re: [RFC][PATCH 09/11] sched, x86: Kill saved_preempt_count
Message-ID: <20150929154627.GR3816@twins.programming.kicks-ass.net>
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On Tue, Sep 29, 2015 at 11:44:04AM -0400, Steven Rostedt wrote:
> On Tue, 29 Sep 2015 11:28:34 +0200
> Peter Zijlstra <peterz@infradead.org> wrote:
> 
> > With the introduction of the context switch preempt_count invariant,
> > and the demise of PREEMPT_ACTIVE, its pointless to save/restore the
> > per-cpu preemption count, it must always be 2.
> > 
> > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> 
> Should we add a warn on someplace:
> 
>  WARN_ON_ONCE(preempt_count() != 2)

See v2 12/11 :-)