Re: gettimeofday() jumping into the future

[John Stultz]

On Mon, 2008-03-31 at 10:55 +0200, Thomas Gleixner wrote:
> 
> > +     if (cycle_now < clock->cycle_last)
> > +             return 0;
> > +
> 
> No, this breaks wrapping clocksources e.g. pmtimer. We need a
> different sanity check for that TSC crap.

Yea. If you're going to do that sort of logic (which requires a costly
cmpxchg as well), it should be done in the read() function of the
clocksource.

thanks
-john
 

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