Re: [RFC PATCH v2] memory-barriers: remove smp_mb__after_unlock_lock()

From: Will Deacon
Date: Wed Aug 12 2015 - 09:44:26 EST


Hello Paul,

On Fri, Jul 24, 2015 at 04:30:46PM +0100, Paul E. McKenney wrote:
> On Fri, Jul 24, 2015 at 12:31:01PM +0100, Will Deacon wrote:
> > On Wed, Jul 15, 2015 at 02:12:21PM +0100, Paul E. McKenney wrote:
> > > > > commit 695c05d4b9666c50b40a1c022678b5f6e2e3e771
> > > > > Author: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
> > > > > Date: Tue Jul 14 18:35:23 2015 -0700
> > > > >
> > > > > rcu,locking: Privatize smp_mb__after_unlock_lock()
> > > > >
> > > > > RCU is the only thing that uses smp_mb__after_unlock_lock(), and is
> > > > > likely the only thing that ever will use it, so this commit makes this
> > > > > macro private to RCU.
> > > > >
> > > > > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
> > > > > Cc: Will Deacon <will.deacon@xxxxxxx>
> > > > > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> > > > > Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
> > > > > Cc: "linux-arch@xxxxxxxxxxxxxxx" <linux-arch@xxxxxxxxxxxxxxx>
> >
> > Are you planning to queue this somewhere? I think it makes sense regardless
> > of whether we change PowerPc or not and ideally it would be merged around
> > the same time as my relaxed atomics series.
>
> I have is in -rcu. By default, I will push it to the 4.4 merge window.
> Please let me know if you need it sooner.

The generic relaxed atomics are now queued in -tip, so it would be really
good to see this Documentation update land in 4.3 if at all possible. I
appreciate it's late in the cycle, but it's always worth asking.

Thanks,

Will
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/