Subject: Re: [PATCH] powerpc/mm: Remove debug context clamping from nohash code

From: Benjamin Herrenschmidt <[email-masked]>
Date: Thu, 05 Nov 2009 16:21:53 +1100

On Wed, 2009-11-04 at 23:16 -0600, Kumar Gala wrote:
> On Nov 4, 2009, at 5:39 PM, Benjamin Herrenschmidt wrote:
> 
> > I inadvertently left that debug code enabled, causing the number of
> > contexts to be clamped to 31 which is going to slow things down on
> > 4xx and just plain breaks 8xx
> >
> > Signed-off-by: Benjamin Herrenschmidt <[email-masked]>
> > ---
> > arch/powerpc/mm/mmu_context_nohash.c |    4 ++--
> > 1 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/ 
> > mmu_context_nohash.c
> > index c2f93dc..be4f34c 100644
> > --- a/arch/powerpc/mm/mmu_context_nohash.c
> > +++ b/arch/powerpc/mm/mmu_context_nohash.c
> > @@ -25,8 +25,8 @@
> >  *     also clear mm->cpu_vm_mask bits when processes are migrated
> >  */
> >
> > -#define DEBUG_MAP_CONSISTENCY
> > -#define DEBUG_CLAMP_LAST_CONTEXT   31
> > +//#define DEBUG_MAP_CONSISTENCY
> > +//#define DEBUG_CLAMP_LAST_CONTEXT   31
> > //#define DEBUG_HARDER
> >
> > /* We don't use DEBUG because it tends to be compiled in always  
> > nowadays
> 
> Can you send this to stable.

No need. .31 doesn't have the clamp, it went in afterward afaik
(my bad) though stable does have DEBUG_MAP_CONSISTENCY which you
may want to remove for perfs.

Cheers,
Ben.