Re: [tip:perfcounters/core] perf_counter: x86: Fix call-chain supportto use NMI-safe methods

[H. Peter Anvin]

Avi Kivity wrote:
> On 06/15/2009 10:02 PM, Peter Zijlstra wrote:
>> Ah, well, I have no idea who expensive cr2 is, if its like a regular
>> register then it should be fine. If however its tons more expensive then
>> we should really avoid it.
> 
> IIRC it's pretty cheap, I measured it once when tuning the kvm context 
> switch code.  I don't recall the exact numbers.
> 

Sounds like a win to me.

	-hpa

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