[PATCH 3/8] time: Explicitly use u32 instead of int for shift values

From: John Stultz
Date: Fri Jul 13 2012 - 01:22:27 EST


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@xxxxxxxxxx>
CC: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
CC: Richard Cochran <richardcochran@xxxxxxxxx>
CC: Prarit Bhargava <prarit@xxxxxxxxxx>
CC: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
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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