Re: [PATCH-tip] locking/pvqspinlock: Relax cmpxchg's to improve performance on some archs

From: Waiman Long
Date: Fri Dec 09 2016 - 11:10:29 EST

On 12/09/2016 11:05 AM, Peter Zijlstra wrote:
> 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.
OK, I will update the patch to either document them with comments or
enumerate them in the change log.