[PATCH] ARM: implement optimized percpu variable access

Will Deacon will.deacon at arm.com
Tue Nov 13 05:40:07 EST 2012


On Mon, Nov 12, 2012 at 09:01:58PM +0000, Rob Herring wrote:
> On 11/12/2012 10:51 AM, Will Deacon wrote:
> > Ok, similar numbers over here so it looks like this is definitely worth
> > doing. However, I still object to the "cc", particularly after discussion
> > with the tools guys here who agree that the behaviour you're seeing is
> > indicative of a buggy compiler. It may even be part of a larger issue with
> > GCC's definition of `reachability' for kernel entry points. For interest, I
> > failed to reproduce with:
> > 
> >   gcc version 4.7.3 20121001 (prerelease) (crosstool-NG linaro-1.13.1-4.7-2012.10-20121022 - Linaro GCC 2012.10)
> > (http://launchpad.net/linaro-toolchain-binaries/trunk/2012.10/+download/gcc-linaro-arm-linux-gnueabihf-4.7-2012.10-20121022_linux.tar.bz2)
> > 
> > which sounds fairly close to the tools that you are using. Please can you
> > file a bug in launchpad? 
> 
> Strangely, I can't reproduce it either now...

Reproduce what? :)

If you remove the "cc" clobber, you can add my ack:

  Acked-by: Will Deacon <will.deacon at arm.com>

Will




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