Messages in this thread | | | Date | Mon, 27 Apr 2015 22:03:29 +0200 | From | Borislav Petkov <> | Subject | Re: [PATCH] x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue |
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On Mon, Apr 27, 2015 at 12:59:11PM -0700, H. Peter Anvin wrote: > It really comes down to this: it seems older cores from both Intel > and AMD perform better with 66 66 66 90, whereas the 0F 1F series is > better on newer cores. > > When I measured it, the differences were sometimes dramatic.
How did you measure that? I should probably do the same on some newer AMD machines... We're using k8_nops on all AMD, even though the optimization manuals cite different NOPs on newer AMD families.
Thanks.
-- Regards/Gruss, Boris.
ECO tip #101: Trim your mails when you reply. --
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