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    Subject2.6.18-rt7: rollover with 32-bit cycles_t
    On ARM, I'm noticing the 'bug' message from check_critical_timing()
    where two calls to get_cycles() are compared and the 2nd is assumed to
    be >= the first.

    This isn't properly handling the case of rollover which occurs
    relatively often with fast hardware clocks and 32-bit cycle counters.

    Is this really a bug? If the get_cycles() can be assumed to run between
    0 and (cycles_t)~0, using the right unsigned math could get a proper
    delta even in the rollover case. Is this a safe assumption?

    Kevin





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