Re: x86, vmi: TSC going backwards check in vmi clocksource

[Alok Kataria]

On Thu, 2009-02-19 at 03:18 -0800, Ingo Molnar wrote:
> * Alok Kataria <akataria@xxxxxxxxxx> wrote:
> 
> > From: Alok N Kataria <akataria@xxxxxxxxxx>
> > 
> > Similar to the check for TSC going backwards in the TSC 
> > clocksource, we also need this check for VMI clocksource.
> 
> ok. Precisely what kind of bug/symptoms does this fix?

If the read CYCLES_REAL counter value is less than the cycle_last value,
it may result in time jumps.
I also saw some messages about  process being stuck for more than
120sec, which was traced back to this.

Thanks,
Alok
> 
> 	Ingo

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