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Date:   Tue, 19 Jun 2018 16:16:42 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Quentin Perret <quentin.perret@arm.com>
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Subject: Re: [RFC PATCH v3 03/10] PM: Introduce an Energy Model management
 framework
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On Tue, Jun 19, 2018 at 02:38:45PM +0100, Quentin Perret wrote:
> But maybe I could use something simpler than a lock in this case ?
> Would WRITE_ONCE/READ_ONCE be enough to ensure that atomicity for
> example ?

Yes, since its a single pointer, smp_store_release() + READ_ONCE()
should be sufficient (these are the foundations of RCU).