Re: [PATCH -tip] Convert CONFIG_SMP=y powerpc defconfigs toTREE_RCU.

From: Paul E. McKenney
Date: Sun Apr 05 2009 - 12:44:32 EST


On Sun, Apr 05, 2009 at 12:17:56PM +0200, Ingo Molnar wrote:
>
> * Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> wrote:
>
> > On Sat, Apr 04, 2009 at 09:21:58AM -0400, Josh Boyer wrote:
> > > On Fri, Apr 3, 2009 at 8:27 PM, Paul E. McKenney
> > > <paulmck@xxxxxxxxxxxxxxxxxx> wrote:
> > > > From: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
> > >
> > > Why would one want to do this? The commit log doesn't explain the
> > > switch and why it's great. Mostly because the commit log doesn't
> > > exist. (I'll stop channeling Andrew now)
> >
> > Indeed, I am sure that I will get the hang the relevant git
> > commands at some point, but clearly am not yet there.
> >
> > The thing that is great about this patch is that it is a step on
> > the way to retiring Classic RCU entirely.
>
> I'd suggest you dont do these dozens of defconfig updates at all -
> arch maintainers can do this themselves, once the core kernel
> default has been flipped.

I am of course personally quite happy with this approach in the short
term, as I would only need to worry about one patch.

My one concern would be that we cannot retire Classic RCU until all the
arch maintainers remove CONFIG_CLASSIC_RCU=y from their defconfig files.
However, given that the attached script suffices, I am not too worried
about that.

Of course, none of this matters unless people agree that Tree RCU has
proven reliable enough to be made default. So, any objections to such
a change at this point?

Thanx, Paul

Attachment: 2rcutree.sh
Description: 2rcutree.sh