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    Subject[PATCH 3/8] time: Explicitly use u32 instead of int for shift values
    Date
    Ingo noted that using a u32 instead of int for shift values
    would be better to make sure the compiler doesn't unnecessarily
    use complex signed arithmetic.

    CC: Ingo Molnar <mingo@kernel.org>
    CC: Peter Zijlstra <a.p.zijlstra@chello.nl>
    CC: Richard Cochran <richardcochran@gmail.com>
    CC: Prarit Bhargava <prarit@redhat.com>
    CC: Thomas Gleixner <tglx@linutronix.de>
    Signed-off-by: John Stultz <john.stultz@linaro.org>
    ---
    kernel/time/timekeeping.c | 6 +++---
    1 file changed, 3 insertions(+), 3 deletions(-)

    diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
    index c2f12aa..4fd83df 100644
    --- a/kernel/time/timekeeping.c
    +++ b/kernel/time/timekeeping.c
    @@ -28,7 +28,7 @@ struct timekeeper {
    /* NTP adjusted clock multiplier */
    u32 mult;
    /* The shift value of the current clocksource. */
    - int shift;
    + u32 shift;
    /* Number of clock cycles in one NTP interval. */
    cycle_t cycle_interval;
    /* Number of clock shifted nano seconds in one NTP interval. */
    @@ -45,7 +45,7 @@ struct timekeeper {
    s64 ntp_error;
    /* Shift conversion between clock shifted nano seconds and
    * ntp shifted nano seconds. */
    - int ntp_error_shift;
    + u32 ntp_error_shift;

    /* The current time */
    struct timespec xtime;
    @@ -960,7 +960,7 @@ static void timekeeping_adjust(s64 offset)
    *
    * Returns the unconsumed cycles.
    */
    -static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
    +static cycle_t logarithmic_accumulation(cycle_t offset, u32 shift)
    {
    u64 nsecps = (u64)NSEC_PER_SEC << timekeeper.shift;
    u64 raw_nsecs;
    --
    1.7.9.5


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