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Subject[PATCH 08/16] ntp: Access tick_length variable via ntp_tick_length()
Date
Currently the NTP managed tick_length value is accessed globally,
in preparations for locking cleanups, make sure it is accessed via
a function and mark it as static.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
include/linux/timex.h | 2 +-
kernel/time/ntp.c | 9 ++++++++-
kernel/time/timekeeping.c | 6 +++---
3 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/include/linux/timex.h b/include/linux/timex.h
index 92e01fc..b75e186 100644
--- a/include/linux/timex.h
+++ b/include/linux/timex.h
@@ -250,7 +250,7 @@ extern void ntp_clear(void);
#define NTP_INTERVAL_LENGTH (NSEC_PER_SEC/NTP_INTERVAL_FREQ)

/* Returns how long ticks are at present, in ns / 2^NTP_SCALE_SHIFT. */
-extern u64 tick_length;
+extern u64 ntp_tick_length(void);

extern void second_overflow(void);
extern int do_adjtimex(struct timex *);
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index ae7e136..f131ba6 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -28,7 +28,7 @@ unsigned long tick_usec = TICK_USEC;
/* ACTHZ period (nsecs): */
unsigned long tick_nsec;

-u64 tick_length;
+static u64 tick_length;
static u64 tick_length_base;

static struct hrtimer leap_timer;
@@ -360,6 +360,13 @@ void ntp_clear(void)
pps_clear();
}

+
+u64 ntp_tick_length(void)
+{
+ return tick_length;
+}
+
+
/*
* Leap second processing. If in leap-insert state at the end of the
* day, the system clock is set back one second; if in leap-delete
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 8f54200..f92e636 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -807,7 +807,7 @@ static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,
* Now calculate the error in (1 << look_ahead) ticks, but first
* remove the single look ahead already included in the error.
*/
- tick_error = tick_length >> (timekeeper.ntp_error_shift + 1);
+ tick_error = ntp_tick_length() >> (timekeeper.ntp_error_shift + 1);
tick_error -= timekeeper.xtime_interval >> 1;
error = ((error - tick_error) >> look_ahead) + tick_error;

@@ -904,7 +904,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
timekeeper.raw_time.tv_nsec = raw_nsecs;

/* Accumulate error between NTP and clock interval */
- timekeeper.ntp_error += tick_length << shift;
+ timekeeper.ntp_error += ntp_tick_length() << shift;
timekeeper.ntp_error -=
(timekeeper.xtime_interval + timekeeper.xtime_remainder) <<
(timekeeper.ntp_error_shift + shift);
@@ -952,7 +952,7 @@ static void update_wall_time(void)
shift = ilog2(offset) - ilog2(timekeeper.cycle_interval);
shift = max(0, shift);
/* Bound shift to one less then what overflows tick_length */
- maxshift = (8*sizeof(tick_length) - (ilog2(tick_length)+1)) - 1;
+ maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1;
shift = min(shift, maxshift);
while (offset >= timekeeper.cycle_interval) {
offset = logarithmic_accumulation(offset, shift);
--
1.7.3.2.146.gca209


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