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Date: Wed, 4 Nov 2015 05:54:31 -0800
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Dmitry Vyukov <dvyukov@google.com>,
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Subject: Re: [GIT PULL] locking changes for v4.4
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On Wed, Nov 04, 2015 at 12:48:50PM +0100, Ingo Molnar wrote:
> 
> * Linus Torvalds <torvalds@linux-foundation.org> wrote:
> 
> > On Tue, Nov 3, 2015 at 3:58 PM, Linus Torvalds
> > <torvalds@linux-foundation.org> wrote:
> > >
> > > I think I'll pull this, but then just make a separate commit to remove
> 
> Thanks!
> 
> > > all the bogus games with "control" dependencies that seem to have no basis is 
> > > reality.
> > 
> > So the attached is what I committed in my tree. [...]
> 
> Acked-by: Ingo Molnar <mingo@kernel.org>
> 
> > +      dependency into nonexistence.  Careful use of READ_ONCE() or
> > +      atomic{,64}_read() can help to preserve your control dependency.
> > +      Please see the Compiler Barrier section for more information.
> 
> So technically it's the "COMPILER BARRIER" section, but this is a pre-existing 
> formulation and the document doesn't use such references consistently so I guess 
> it doesn't matter much.

I will take a pass through and fix these up.  I don't see this as urgent,
so will add it to my patches for the next merge window.

							Thanx, Paul