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    SubjectRe: 2.5.40-mm2
    Robert Love wrote:
    >
    > On Sun, 2002-10-06 at 18:07, Andrew Morton wrote:
    >
    > > > - while (base->running_timer == timer) {
    > > > + while (base->running_timer == timer)
    > > > cpu_relax();
    > > > - preempt_disable();
    > > > - preempt_enable();
    >
    > I am confused as to why Ingo would put these here. He knows very well
    > what he is doing... surely he had a reason.
    >
    > If he intended to force a preemption point here, then the lines needs to
    > be reversed. This assumes, of course, preemption is disabled here. But
    > I do not think it is.
    >
    > If he just wanted to check for preemption, we have a
    > preempt_check_resched() which does just that (I even think he wrote
    > it). Note as long as interrupts are enabled this probably does not
    > achieve much anyhow.
    >

    I think it's a way of doing "cond_resched() if cond_resched() is
    a legal thing to do right now".

    I'm sure David isn't using preempt though.
    -
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