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    SubjectRe: 2.6.20-rc6-mm3
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    Date
    On Mon, 2007-01-29 at 20:45 -0800, Andrew Morton wrote:
    > Temporarily at
    >
    > http://userweb.kernel.org/~akpm/2.6.20-rc6-mm3/
    >
    > Will appear later at
    >
    > ftp://ftp.kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.20-rc6/2.6.20-rc6-mm3/
    >

    I was running likely profiling and I noticed that when I turn on the
    "tickless" option I get the following line,

    +unlikely | 21111208| 9367278 need_resched()@:include/linux/sched.h@1597
    This means that this line is 21111208 true, and 9367278 false.
    This existed on bootup, and stayed after about 7 hours of runtime
    (mostly idle). Since need_resched is a "static inline" there are
    multiple instances of need_resched() in the kernel. If I turn off the
    "tickless" feature this wrong unlikely disappears, and the output looks
    like this,

    unlikely | 0| 169 need_resched()@:include/linux/sched.h@1597
    unlikely | 0| 94 need_resched()@:include/linux/sched.h@1597
    unlikely | 0| 63 need_resched()@:include/linux/sched.h@1597
    unlikely | 0| 19 need_resched()@:include/linux/sched.h@1597
    unlikely | 0| 379 need_resched()@:include/linux/sched.h@1597
    unlikely | 1| 202596 need_resched()@:include/linux/sched.h@1597
    unlikely | 7| 205929 need_resched()@:include/linux/sched.h@1597
    unlikely | 6461| 271690 need_resched()@:include/linux/sched.h@1597
    Only a little after boot. I suppose this could be a natural side effect
    of the tickless feature but I thought I would report it anyway.

    Daniel

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