From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH 05/11] qspinlock: Optimize for smaller NR_CPUS
Date: Wed, 18 Jun 2014 13:39:52 +0200
Message-ID: <53A17A88.7090705@redhat.com>
References: <20140615124657.264658593@chello.nl>
	<20140615130153.483502389@chello.nl>
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To: Peter Zijlstra <a.p.zijlstra@chello.nl>, Waiman.Long@hp.com, tglx@linutronix.de, mingo@kernel.org
Cc: linux-arch@vger.kernel.org, riel@redhat.com, gleb@redhat.com, kvm@vger.kernel.org, konrad.wilk@oracle.com, Peter Zijlstra <peterz@infradead.org>, scott.norton@hp.com, raghavendra.kt@linux.vnet.ibm.com, paolo.bonzini@gmail.com, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, chegu_vinod@hp.com, david.vrabel@citrix.com, oleg@redhat.com, xen-devel@lists.xenproject.org, boris.ostrovsky@oracle.com, paulmck@linux.vnet.ibm.com, torvalds@linux-foundation.org
List-Id: virtualization@lists.linuxfoundation.org

Il 15/06/2014 14:47, Peter Zijlstra ha scritto:
>
> -	for (;;) {
> -		new = (val & ~_Q_PENDING_MASK) | _Q_LOCKED_VAL;
> -
> -		old = atomic_cmpxchg(&lock->val, val, new);
> -		if (old == val)
> -			break;
> -
> -		val = old;
> -	}
> +	clear_pending_set_locked(lock, val);
>  	return;


Might as well add clear_pending_set_locked already in patch 3.

Paolo