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    SubjectRe: Q: sched_clock() vs. clocksource, how to implement correctly
    On Fri, 2010-04-23 at 18:29 +0200, Martin Schwidefsky wrote:
    > > Questions:
    > >
    > > - Isn't sched_clock() supposed to be extended to 64bit so
    > > that it practically never wraps?
    > > (old implementations use cnt32_to_63())
    > Yes, sched_clock() is supposed to return a monotonic timestamp.
    > > - What would be the effect on scheduling when sched_clock() wraps?
    > It would confuse the process accounting and the scheduling I guess.

    Are you sure about this? I'm pretty sure I've seen Ingo say multiple
    times that sched_clock can wrap, and can be unstable. For instance
    sched_clock is (was?) directly connected to the TSC on x86 ..

    If it really can't wrap there must bunches of architectures that would
    need to be fixed up.


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