Re: [PATCH 1/5] Add a global synchronization point for pvclock

[Avi Kivity]

On 04/19/2010 01:46 PM, Peter Zijlstra wrote:
> On Sat, 2010-04-17 at 21:48 +0300, Avi Kivity wrote:
>    
> > > After this patch is applied, I don't see a single warp in time during 5 days
> > > of execution, in any of the machines I saw them before.
> > >
> > >
> > >        
> > Please define a cpuid bit that makes this optional.  When we eventually
> > enable it in the future, it will allow a wider range of guests to enjoy it.
> >      
> Right, so on x86 we have:
>
> X86_FEATURE_CONSTANT_TSC, which only states that TSC is frequency
> independent, not that it doesn't stop in C states and similar fun stuff.
>
> X86_FEATURE_TSC_RELIABLE, which IIRC should indicate the TSC is constant
> and synced between cores.
>
>    

Sockets and boards too?  (IOW, how reliable is TSC_RELIABLE)?

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

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