Re: FOR REVIEW: New x86-64 vsyscall vgetcpu()

Andi Kleen
2006-06-17T06:58:39Z

> That work could form the basis for a low-impact method of exporting
> the current CPU to user space via a read-only mapped page. I'll admit
> to having zero knowledge of whether this would be workable on anything
> other than ia64.

On x86 per CPU mappings are not really feasible. That is because
the CPU uses the Linux page tables directly and to change them
per CPU you would need to fork them per CPU. That would add so much
complications that I don't even want to think them all through ...

-andi