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

[Avi Kivity]

On 04/19/2010 01:51 PM, Peter Zijlstra wrote:
>    
> > > 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)?
> >      
> Not sure, IIRC we clear that when the TSC sync test fails, eg when we
> mark the tsc clocksource unusable.
>    

Worrying.  By the time we detect this the guest may already have gotten 
confused by clocks going backwards.

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

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