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Date: Mon, 12 Mar 2018 14:31:35 +0100
From: Peter Zijlstra <peterz@infradead.org>
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Subject: Re: smp_mb__after_spinlock requirement too strong?
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On Mon, Mar 12, 2018 at 05:13:03PM +0800, 焦晓冬 wrote:

> If the fixed comment could point out where this RCsc is used, it will be great.

The one that comes to mind first is RCU-sched, that relies on a context
switch implying a full smp_mb(). But I think there's more..