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Message-ID: <1390943840.11839.10.camel@buesod1.americas.hpqcorp.net>
Subject: Re: [PATCH v2 2/5] mutex: Modify the way optimistic spinners are
 queued
From: Davidlohr Bueso <davidlohr@hp.com>
To: paulmck@linux.vnet.ibm.com
Cc: Jason Low <jason.low2@hp.com>, mingo@redhat.com, peterz@infradead.org,
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Date: Tue, 28 Jan 2014 13:17:20 -0800
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On Tue, 2014-01-28 at 12:23 -0800, Paul E. McKenney wrote:
> On Tue, Jan 28, 2014 at 11:13:13AM -0800, Jason Low wrote:
> > ...
> >  		if (!owner && (need_resched() || rt_task(task)))
> > -			goto slowpath;
> > +			break;
> > 
> >  		/*
> >  		 * The cpu_relax() call is a compiler barrier which forces
> > @@ -514,6 +511,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass,
> >  		 */
> >  		arch_mutex_cpu_relax();
> >  	}
> > +	mspin_unlock(MLOCK(lock), &node);
> >  slowpath:
> 
> Are there any remaining goto statements to slowpath?  If so, they need
> to release the lock.  If not, this label should be removed.

We still have the !mutex_can_spin_on_owner case.

Thanks,
Davidlohr