[PATCH 02/16] time: Move wall_to_monotonic into the timekeeper structure

From: John Stultz
Date: Mon Nov 14 2011 - 23:05:10 EST


In preparation for locking cleanups, move wall_to_monotonic
into the timekeeper structure.

CC: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CC: Eric Dumazet <eric.dumazet@xxxxxxxxx>
CC: Richard Cochran <richardcochran@xxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
kernel/time/timekeeping.c | 69 ++++++++++++++++++++++++---------------------
1 files changed, 37 insertions(+), 32 deletions(-)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index bd8e7fd..15740b5 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -48,6 +48,21 @@ struct timekeeper {
/* NTP adjusted clock multiplier */
u32 mult;

+ /*
+ * wall_to_monotonic is what we need to add to xtime (or xtime corrected
+ * for sub jiffie times) to get to monotonic time. Monotonic is pegged
+ * at zero at system boot time, so wall_to_monotonic will be negative,
+ * however, we will ALWAYS keep the tv_nsec part positive so we can use
+ * the usual normalization.
+ *
+ * wall_to_monotonic is moved after resume from suspend for the
+ * monotonic time not to jump. We need to add total_sleep_time to
+ * wall_to_monotonic to get the real boot based time offset.
+ *
+ * - wall_to_monotonic is no longer the boot time, getboottime must be
+ * used instead.
+ */
+ struct timespec wall_to_monotonic;
/* time spent in suspend */
struct timespec total_sleep_time;

@@ -148,21 +163,8 @@ __cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);

/*
* The current time
- * wall_to_monotonic is what we need to add to xtime (or xtime corrected
- * for sub jiffie times) to get to monotonic time. Monotonic is pegged
- * at zero at system boot time, so wall_to_monotonic will be negative,
- * however, we will ALWAYS keep the tv_nsec part positive so we can use
- * the usual normalization.
- *
- * wall_to_monotonic is moved after resume from suspend for the monotonic
- * time not to jump. We need to add total_sleep_time to wall_to_monotonic
- * to get the real boot based time offset.
- *
- * - wall_to_monotonic is no longer the boot time, getboottime must be
- * used instead.
*/
static struct timespec xtime __attribute__ ((aligned (16)));
-static struct timespec wall_to_monotonic __attribute__ ((aligned (16)));

/*
* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock.
@@ -176,8 +178,8 @@ int __read_mostly timekeeping_suspended;
void timekeeping_leap_insert(int leapsecond)
{
xtime.tv_sec += leapsecond;
- wall_to_monotonic.tv_sec -= leapsecond;
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
+ timekeeper.wall_to_monotonic.tv_sec -= leapsecond;
+ update_vsyscall(&xtime, &timekeeper.wall_to_monotonic, timekeeper.clock,
timekeeper.mult);
}

@@ -249,8 +251,8 @@ ktime_t ktime_get(void)

do {
seq = read_seqbegin(&xtime_lock);
- secs = xtime.tv_sec + wall_to_monotonic.tv_sec;
- nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec;
+ secs = xtime.tv_sec + timekeeper.wall_to_monotonic.tv_sec;
+ nsecs = xtime.tv_nsec + timekeeper.wall_to_monotonic.tv_nsec;
nsecs += timekeeping_get_ns();

} while (read_seqretry(&xtime_lock, seq));
@@ -281,7 +283,7 @@ void ktime_get_ts(struct timespec *ts)
do {
seq = read_seqbegin(&xtime_lock);
*ts = xtime;
- tomono = wall_to_monotonic;
+ tomono = timekeeper.wall_to_monotonic;
nsecs = timekeeping_get_ns();

} while (read_seqretry(&xtime_lock, seq));
@@ -370,14 +372,15 @@ int do_settimeofday(const struct timespec *tv)

ts_delta.tv_sec = tv->tv_sec - xtime.tv_sec;
ts_delta.tv_nsec = tv->tv_nsec - xtime.tv_nsec;
- wall_to_monotonic = timespec_sub(wall_to_monotonic, ts_delta);
+ timekeeper.wall_to_monotonic =
+ timespec_sub(timekeeper.wall_to_monotonic, ts_delta);

xtime = *tv;

timekeeper.ntp_error = 0;
ntp_clear();

- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
+ update_vsyscall(&xtime, &timekeeper.wall_to_monotonic, timekeeper.clock,
timekeeper.mult);

write_sequnlock_irqrestore(&xtime_lock, flags);
@@ -409,12 +412,13 @@ int timekeeping_inject_offset(struct timespec *ts)
timekeeping_forward_now();

xtime = timespec_add(xtime, *ts);
- wall_to_monotonic = timespec_sub(wall_to_monotonic, *ts);
+ timekeeper.wall_to_monotonic =
+ timespec_sub(timekeeper.wall_to_monotonic, *ts);

timekeeper.ntp_error = 0;
ntp_clear();

- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
+ update_vsyscall(&xtime, &timekeeper.wall_to_monotonic, timekeeper.clock,
timekeeper.mult);

write_sequnlock_irqrestore(&xtime_lock, flags);
@@ -588,7 +592,7 @@ void __init timekeeping_init(void)
boot.tv_sec = xtime.tv_sec;
boot.tv_nsec = xtime.tv_nsec;
}
- set_normalized_timespec(&wall_to_monotonic,
+ set_normalized_timespec(&timekeeper.wall_to_monotonic,
-boot.tv_sec, -boot.tv_nsec);
timekeeper.total_sleep_time.tv_sec = 0;
timekeeper.total_sleep_time.tv_nsec = 0;
@@ -614,7 +618,8 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta)
}

xtime = timespec_add(xtime, *delta);
- wall_to_monotonic = timespec_sub(wall_to_monotonic, *delta);
+ timekeeper.wall_to_monotonic =
+ timespec_sub(timekeeper.wall_to_monotonic, *delta);
timekeeper.total_sleep_time = timespec_add(
timekeeper.total_sleep_time, *delta);
}
@@ -647,7 +652,7 @@ void timekeeping_inject_sleeptime(struct timespec *delta)

timekeeper.ntp_error = 0;
ntp_clear();
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
+ update_vsyscall(&xtime, &timekeeper.wall_to_monotonic, timekeeper.clock,
timekeeper.mult);

write_sequnlock_irqrestore(&xtime_lock, flags);
@@ -970,7 +975,7 @@ static void update_wall_time(void)
}

/* check to see if there is a new clocksource to use */
- update_vsyscall(&xtime, &wall_to_monotonic, timekeeper.clock,
+ update_vsyscall(&xtime, &timekeeper.wall_to_monotonic, timekeeper.clock,
timekeeper.mult);
}

@@ -988,9 +993,9 @@ static void update_wall_time(void)
void getboottime(struct timespec *ts)
{
struct timespec boottime = {
- .tv_sec = wall_to_monotonic.tv_sec +
+ .tv_sec = timekeeper.wall_to_monotonic.tv_sec +
timekeeper.total_sleep_time.tv_sec,
- .tv_nsec = wall_to_monotonic.tv_nsec +
+ .tv_nsec = timekeeper.wall_to_monotonic.tv_nsec +
timekeeper.total_sleep_time.tv_nsec
};

@@ -1019,7 +1024,7 @@ void get_monotonic_boottime(struct timespec *ts)
do {
seq = read_seqbegin(&xtime_lock);
*ts = xtime;
- tomono = wall_to_monotonic;
+ tomono = timekeeper.wall_to_monotonic;
sleep = timekeeper.total_sleep_time;
nsecs = timekeeping_get_ns();

@@ -1092,7 +1097,7 @@ struct timespec get_monotonic_coarse(void)
seq = read_seqbegin(&xtime_lock);

now = xtime;
- mono = wall_to_monotonic;
+ mono = timekeeper.wall_to_monotonic;
} while (read_seqretry(&xtime_lock, seq));

set_normalized_timespec(&now, now.tv_sec + mono.tv_sec,
@@ -1127,7 +1132,7 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
do {
seq = read_seqbegin(&xtime_lock);
*xtim = xtime;
- *wtom = wall_to_monotonic;
+ *wtom = timekeeper.wall_to_monotonic;
*sleep = timekeeper.total_sleep_time;
} while (read_seqretry(&xtime_lock, seq));
}
@@ -1142,7 +1147,7 @@ ktime_t ktime_get_monotonic_offset(void)

do {
seq = read_seqbegin(&xtime_lock);
- wtom = wall_to_monotonic;
+ wtom = timekeeper.wall_to_monotonic;
} while (read_seqretry(&xtime_lock, seq));
return timespec_to_ktime(wtom);
}
--
1.7.3.2.146.gca209

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