Re: perf uncore & lkvm woes

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On 08/21/2012 10:11 AM, Peter Zijlstra wrote:
> On Sun, 2012-08-19 at 12:55 +0300, Avi Kivity wrote:
>> > I think Avi prefers the method where KVM 'fakes' the MSRs and we have to
>> > detect if the MSRs actually work or not.
>> 
>> s/we have/we don't have/. 
> 
> So for the 'normal' PMU we actually do check to see if the MSRs are
> being faked and bail if they are.

That was because earlier versions of kvm did not virtualize the pmu.

The approaches are not mutually exclusive.  We can check in the guest,
and fake it in the host.

The problem with faking it in the host is if someone actually relies on
the pmu for something, not just instrumentation.  We do that for the
watchdog, but I don't see it happening with the uncore pmu.


-- 
error compiling committee.c: too many arguments to function
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