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

Andi Kleen
2007-11-20T03:30:41Z

> 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