Subject: Re: [PATCH] powerpc: POWER7 optimised copy_to_user/copy_from_user using VMX

From: Benjamin Herrenschmidt <[email-masked]>
Date: Mon, 19 Dec 2011 14:19:07 +1100

On Mon, 2011-12-19 at 14:00 +1100, Benjamin Herrenschmidt wrote:
> On Thu, 2011-12-08 at 17:11 +1100, Anton Blanchard wrote:
> > Implement a POWER7 optimised copy_to_user/copy_from_user using VMX.
> > For large aligned copies this new loop is over 10% faster, and for
> > large unaligned copies it is over 200% faster.
> 
> Breaks !CONFIG_ALTIVEC build an pops some WARN's with preempt & lockdep,
> this seems to fix them:

And it's missing another ifdef actually for !CONFIG_ALTIVEC, I'll fix it
locally and will put a fixed version in -next.

Cheers,
Ben.