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Date: Thu, 30 Nov 2017 10:15:32 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Boqun Feng <boqun.feng@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>,
        Daniel Lustig <dlustig@nvidia.com>,
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        David Howells <dhowells@redhat.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Kernel development list <linux-kernel@vger.kernel.org>
Subject: Re: Unlock-lock questions and the Linux Kernel Memory Model
Message-ID: <20171130091532.qdczu5zz43okruu6@hirez.programming.kicks-ass.net>
References: <17506ed0-1ce8-791d-7cf1-c40426015a99@nvidia.com>
 <Pine.LNX.4.44L0.1711291409440.1369-100000@iolanthe.rowland.org>
 <20171130085509.GA9516@tardis>
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On Thu, Nov 30, 2017 at 04:55:09PM +0800, Boqun Feng wrote:
> But in case of AMOs, which directly send the addition request to memory
> controller, so there wouldn't be any read part or even write part of the
> atomic_inc() executed by CPU. Would this be allowed then?

Personally I bloody hate AMOs that don't respect the normal way of
things.