From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH -v3 7/8] locking: Move smp_cond_load_acquire() and
 friends into asm-generic/barrier.h
Date: Wed, 1 Jun 2016 14:45:41 +0200
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Cc: Waiman Long <waiman.long@hpe.com>, linux-kernel@vger.kernel.org,
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To: Will Deacon <will.deacon@arm.com>
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On Wed, Jun 01, 2016 at 01:13:33PM +0100, Will Deacon wrote:
> On Wed, Jun 01, 2016 at 02:06:54PM +0200, Peter Zijlstra wrote:

> > Works for me; but that would loose using cmpwait() for
> > !smp_cond_load_acquire() spins, you fine with that?
> > 
> > The two conversions in the patch were both !acquire spins.
> 
> Maybe we could go the whole hog and add smp_cond_load_relaxed?

What about say the cmpxchg loops in queued_write_lock_slowpath()
? Would that be something you'd like to use wfe for?

Writing those in smp_cond_load_{acquire,relaxed)() is somewhat possible
but quite ugleh.