Re: [rfc 00/45] [RFC] CPU ops and a rework of per cpu data handling on x86_64

[Andi Kleen]

> Although we have a per-cpu area base in a fixed global register
> for addressing, the above isn't beneficial on sparc64 because
> the atomic is much slower than doing a:
>
> 	local_irq_disable();
> 	nonatomic_percpu_memory_op();
> 	local_irq_enable();

Again might be pointing out the obvious, but you 
need of course save_flags()/restore_flags(), not disable/enable().

If it was just disable/enable x86 could do it much faster too 
and Christoph probably would never felt the need to approach
this project for his SLUB fast path.

-Andi
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