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Subject: Re: [PATCH] powerpc: Optimise per cpu accesses on 64bit
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Alan Modra <amodra@gmail.com>
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On Wed, 2010-06-02 at 08:10 +0930, Alan Modra wrote:
> Not r12.  It is used in function prologue and epilogue code.  If you
> want a dedicated gpr I think you'll need to use (and lose) one of the
> non-volatile regs. 

Which would probably not be a big deal... 

Cheers,
Ben.