Re: [PATCH 05/10] x86_64: Use generic percpu

[Christoph Lameter]

On Sat, 29 Dec 2007, Andi Kleen wrote:

> Anyways the difference between the x86 percpu.h and the generic one is
> that x86-64 uses a short cut through the PDA to get the current cpu
> offset for the current CPU case. The generic one goes through 
> smp_processor_id()->array reference instead. 

No the patch also uses the pda.

> I would request that this optimization is not being removed
> without suitable replacement in the same patchkit.

The optimization was not removed __my_cpu_offset is used to calculate the 
current offset which is using the pda.

#define __my_cpu_offset read_pda(data_offset)

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