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    Subject[PATCH] TIMERS: add missing compensation for HZ == 250.
    From
    Hello.

    Add missing compensation for (HZ == 250) != (1 << SHIFT_HZ) in
    second_overflow().

    Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

    diff --git a/kernel/timer.c b/kernel/timer.c
    --- a/kernel/timer.c
    +++ b/kernel/timer.c
    @@ -752,6 +752,15 @@ static void second_overflow(void)
    else
    time_adj += (time_adj >> 2) + (time_adj >> 5);
    #endif
    +#if HZ == 250
    + /* Compensate for (HZ==250) != (1 << SHIFT_HZ).
    + * Add 1.5625% and 0.78125% to get 255.85938; => only 0.05% error (p. 14)
    + */
    + if (time_adj < 0)
    + time_adj -= (-time_adj >> 6) + (-time_adj >> 7);
    + else
    + time_adj += (time_adj >> 6) + (time_adj >> 7);
    +#endif
    #if HZ == 1000
    /* Compensate for (HZ==1000) != (1 << SHIFT_HZ).
    * Add 1.5625% and 0.78125% to get 1023.4375; => only 0.05% error (p. 14)
    --
    YOSHIFUJI Hideaki @ USAGI Project <yoshfuji@linux-ipv6.org>
    GPG-FP : 9022 65EB 1ECF 3AD1 0BDF 80D8 4807 F894 E062 0EEA
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