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Date:   Tue, 8 Dec 2020 09:11:29 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     "Paul E. McKenney" <paulmck@kernel.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 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.