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    SubjectRe: Ktimer / -rt9 (+custom) monotonic_clock going backwards.
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    On Wed, 2005-10-19 at 10:59 -0400, Steven Rostedt wrote:
    > Hi Thomas,
    >
    > I switched my custom kernel timer to use the ktimers with the prio of -1
    > as you mentioned to me offline. I set up the timer to be monotonic and
    > have a requirement that the returned time is always greater or equal to
    > the last time returned from do_get_ktime_mono.
    >
    > Now here's the results that I got between two calls of do_get_ktime_mono
    >
    > 358.069795728 secs then later 355.981483177. Should this ever happen?

    Definitely not. monotonic time must go forwards.

    > I haven't look to see if this happens in vanilla -rt10 but I haven't
    > touched your ktimer code except for my logging and the patch with the
    > unlock_ktimer_base (since I was based off of -rt9)

    The ktimer code itself calls the timeofday code, which provides the
    monotonic clock. I have no idea what might go wrong.

    Is this reproducible ?

    tglx


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