Re: [RFC 00/15] x86_64: Optimize percpu accesses

[H. Peter Anvin]

Mike Travis wrote:
> Eric W. Biederman wrote:
> ...
> > Another alternative that almost fares better then a segment with
> > a base of zero is a base of -32K or so.  Only trouble that would get us
> > manually managing the per cpu area size again.
>
> One thing to remember is the eventual goal is implementing the cpu_alloc
> functions which I think we've agreed has to be "growable".  This means that
> the addresses will need to be virtual to allow the same offsets for all cpus.
> The patchset I have uses 2Mb pages.  This "little" twist might figure into the
> implementation issues that are being discussed.

No, since the *addresses* can be arbitrary.  The current issue is about 
*offsets.*

	-hpa

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