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From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Marco Elver <elver@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
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Subject: Re: [patch 3/3] tick: Annotate tick_do_timer_cpu data races
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On Tue, Dec 08, 2020 at 09:11:29AM +0100, Peter Zijlstra wrote:
> On Mon, Dec 07, 2020 at 11:44:06AM -0800, Paul E. McKenney wrote:
> 
> > Also, in this particular case, why data_race() rather than READ_ONCE()?
> > Do we really expect the compiler to be able to optimize this case
> > significantly without READ_ONCE()?
> 
> It's about intent and how the code reads. READ_ONCE() is something
> completely different from data_race(). data_race() is correct here.

Why?

							Thanx, Paul