>On Fri, Sep 2, 2011 at 6:29 AM, Michael Mueller <ss7box@xxxxxxxxx> wrote:
>
> >> > >
> >> > > 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;
> >> > > }
I have tried this on 2 panda boards. Both of them fail this simple
test with vanilla (both single core and SMP) kernels (2.6.39-rc4
mainline with high-resolution timer patch, 3.0.1 mainline with
high-resolution timer patch, 3.1-rc2 OMAP git tree without any patch
but with high-resolution timer enabled) within a few seconds to an
hour. Time goes backwards from as low as 234 nsec to 53 usec. The
problem does not reproduce without high resolution timer (i.e by
enabling 32 KHz timer in kernel config) for several hours of testing.
Everyone, could you please try this test on any other ARM boards (and
x86 machines?) with high resolution timer support?
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