Re: [PATCH RFC/RFB] x86_64, i386: interrupt dispatch changes

From: Ingo Molnar
Date: Tue Nov 04 2008 - 16:54:22 EST



* H. Peter Anvin <hpa@xxxxxxxxx> wrote:

> Ingo Molnar wrote:
> > * Ingo Molnar <mingo@xxxxxxx> wrote:
> >
> >> And as hpa's comments point it out, compressing the rather stupid
> >> irq stubs might be a third option that looks promising as well.
> >
> > ... and we should try and see how far we can compress those stubs,
> > before we do any segment register based tricks.
> >
>
> Using the techniques previously mentioned, for 224 vectors:
>
> 1792 bytes ( 8 bytes/stub) - trivial.
> 1568 bytes ( 7 bytes/stub) - same without alignment.
> 952 bytes (~4 bytes/stub) - extra jump needed.
>
> For comparison, the IDT itself is 2048 bytes on x86-32 and 4096 bytes on
> x86-64.

sounds like a plan :)

Ingo
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