Re: [patch] x86: optimize __pa() to be linear again on 64-bit x86

From: Andi Kleen
Date: Tue Feb 24 2009 - 11:02:46 EST


Ingo Molnar <mingo@xxxxxxx> writes:
>
> Yeah, we can do this complete conversion.
>
> I'll clean it up some more. I think the best representation of
> this will be via a virt_to_sym() and sym_to_virt() space. That
> makes it really clear when we are moving from the symbol space
> to the linear space and back.
>
> That way we wont need the _slow() methods at all - we'll always
> know whether an address is pure linear or in the symbol space.
>
> In other words, it will be even faster and even nicer ;-)

That is what the original code did (virt_to_sym was just
done through __pa_symbol), but it was sometimes tricky
to get right andLinus wanted an unified __pa/__va
and put it out of line.

-Andi
--
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
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