Re: [plex86] Performance enhancement: elminiating mode and context

[James Mastros]

On Sun, Dec 17, 2000 at 01:44:51PM +0100, Ramon van Handel wrote:
> like to run ring0 code in (sandboxed) ring0, if possible.
Ahh, now I remember fully what I was thinking with ring0 -> ring1.

We can make the nexus code ring1 and JMP to it instead of taking an INT3
into it.  This should help preformance.  Of course, it can only be done when
the instruction to be virtualized is >4 bytes.  (We need to to a far jump, a
five-byte opcode.)  

So ring3 can normaly run no-SBE, ring0 code runs in ring1 with SBE, but with
less faults, and ring1,2 run SBE in their natural ring.

Does this help at all?  Can the nexus code be ring1 usefuly?  If not, how
about using call gates, are they more efficent then interupt gates?

      -=- James Mastros
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