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    Subject[patch 12/19] SPARC64: Fix serious bug in sched_clock() on sparc64
    -stable review patch.  If anyone has any objections, please let us know.

    ------------------
    From: David S. Miller <davem@davemloft.net>

    [SPARC64]: Fix sched_clock() wrapping every ~17 seconds.

    Unfortunately, sparc64 doesn't have an easy way to do a "64 X 64 -->
    128" bit multiply like PowerPC and IA64 do. We were doing a
    "64 X 64 --> 64" bit multiple which causes overflow very quickly with
    a 30-bit quotient shift.

    So use a quotientshift count of 10 instead of 30, just like x86 and
    ARM do.

    This also fixes the wrapping of printk timestamp values every ~17
    seconds.

    Signed-off-by: David S. Miller <davem@davemloft.net>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    arch/sparc64/kernel/time.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    --- linux-2.6.17.13.orig/arch/sparc64/kernel/time.c
    +++ linux-2.6.17.13/arch/sparc64/kernel/time.c
    @@ -1105,7 +1105,7 @@ static struct time_interpolator sparc64_
    };

    /* The quotient formula is taken from the IA64 port. */
    -#define SPARC64_NSEC_PER_CYC_SHIFT 30UL
    +#define SPARC64_NSEC_PER_CYC_SHIFT 10UL
    void __init time_init(void)
    {
    unsigned long clock = sparc64_init_timers();
    --
    -
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