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    SubjectRe: preempt-timing-2.6.8-rc1
    William Lee Irwin III wrote:
    >>+ unsigned long preempt_exit
    >>+ = (unsigned long)__builtin_return_address(0);
    >>+ hold = sched_clock() - __get_cpu_var(preempt_timings) +
    >>999999;
    >>+ do_div(hold, 1000000);
    >>+ if (preempt_thresh && hold > preempt_thresh &&
    >>+ printk_ratelimit()) {

    On Tue, Jul 13, 2004 at 10:51:24PM +1000, Nick Piggin wrote:
    > This looks wrong. This means hold times of 1ns to 1000000ns trigger the
    > exceeded 1ms threshold, 1000001 to 2000000 trigger the 2ms one, etc.
    > Removing the + 999999 gives the correct result:
    > 1000000 - 1999999ns triggers the 1ms threshold
    > 2000000 - 2999999ns triggers the 2ms threshold
    > etc
    > Or have I missed something?

    AFAICT this is nothing more than rounding up.


    -- wli
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