Date: Fri, 9 Dec 2016 17:05:34 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Waiman Long <longman@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>, linux-kernel@vger.kernel.org,
        Pan Xinhui <xinhui@linux.vnet.ibm.com>,
        Boqun Feng <boqun.feng@gmail.com>, Will Deacon <will.deacon@arm.com>
Subject: Re: [PATCH-tip] locking/pvqspinlock: Relax cmpxchg's to improve
 performance  on some archs
Message-ID: <20161209160534.GX3124@twins.programming.kicks-ass.net>
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On Tue, Dec 06, 2016 at 02:14:42PM -0500, Waiman Long wrote:
> A number of cmpxchg calls in qspinlock_paravirt.h were replaced by more
> relaxed versions to improve performance on architectures that use LL/SC.

I would feel so much better if each change were to have some rationale
included. Either enumerate them in the changelog, or split them up into
smaller patches.