Re: [PATCH V3] perf & kvm: Enhance perf to collect KVM guest os statistics from host side

Sheng Yang
2010-04-14T10:36:07Z

On Wednesday 14 April 2010 18:33:37 Avi Kivity wrote:
> On 04/14/2010 01:27 PM, Sheng Yang wrote:
> >> Yes, interesting to see what the latency is. If it's reasonably short
> >> (and I expect it will be so), we can do the busy wait solution.
> >>
> >> If we have an NMI counter somewhere, we can simply wait until it
> >> changes.
> >
> > Good idea. Of course we have one(at least on x86). There is
> > irq_stat.irq__nmi_count for per cpu. :)
>
> Okay, but kvm doesn't want to know about it. How about a new arch
> function, invoke_nmi_sync(), that will trigger the NMI and wait for it?
>
Sound reasonable. Would try it.

--
regards
Yang, Sheng