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Message-ID: <1361540926.26780.56.camel@laptop>
Subject: Re: [PATCH 0/2] cpustat: use atomic operations to read/update stats
From: Peter Zijlstra <peterz@infradead.org>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Kevin Hilman <khilman@linaro.org>,
        Russell King <rmk+kernel@arm.linux.org.uk>,
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Date: Fri, 22 Feb 2013 14:48:46 +0100
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On Fri, 2013-02-22 at 13:50 +0100, Frederic Weisbecker wrote:
> atomic64_read() and atomic64_set() are supposed to take care of that,
> without
> even the need for _inc() or _add() parts that use LOCK.

Are you sure? Generally atomic*_set() is not actually an atomic
operation.