Mike,
On Thu, 1 Sep 2011, Michael Mueller wrote:
> On Thu, Sep 1, 2011 at 3:33 PM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
>
> >
> > That looks like a problem in the clocksource. i.e. time is going
> > backward or having weird momentary jumps. You could verify that by
> > running one ore more tight loops which do
> >
> > clock_gettime(CLOCK_MONOTONIC, &prev);
> > while (1) {
> > clock_gettime(CLOCK_MONOTONIC, &curr);
> > if (curr < prev) /* Use a proper compare function for
> > timespec! */
> > printf(.....);
> > prev = curr;
> > }
> >
> > If that triggers on RT or on a vanilla kernel, then the problem is
> > definitely somewhere in the timekeeping/clocksource area.
>
>
> have seen this problem in vanilla kernels; developed a work-around that
> calls
> clock_gettime(CLOCK_MONOTONIC, &curr); until curr>prev
> a couple of times, and if that doesn't work, then it gets a new prev value
> and a new curr value; rinse and repeat until curr<prev; not sure what
> precipitates the problem; will post workaround code if wanted
Is that on a Panda board as well?
Thanks,
tglx
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