Re: [PATCH] KVM: VMX: Enable memory mappedTPR shadow(FlexPriority)

Dong, Eddie
2007-10-30T15:07:19Z

>
> Yes. FlexPriority will be both faster and safer for those who have it
> than my hack.
>
> It may turn out that patching can improve performance even with
> FlexPriority: we can patch the APIC EOI write to look if any
> interrupts are pending, and only exit if the EOI will result in a new
> interrupt being injected. But it is very possible that this will not
> be necessary if we can achieve good interrupt mitigation with virtio.
>
Mmm, I won't say so. The issues is: A guest EOI (level triggered IRQ)
need to clear remote IRR bit in IOAPIC side and resample that pin in
IOAPIC side.
This one is not easy to do in patched code.

thx,eddie