[PATCH 03/16] time: Move xtime into timekeeeper structure

From: John Stultz
Date: Mon Nov 14 2011 - 23:04:26 EST


In preparation for locking cleanups, move xtime into
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 | 91 +++++++++++++++++++++++----------------------
1 files changed, 47 insertions(+), 44 deletions(-)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 15740b5..6c64931 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -48,6 +48,8 @@ struct timekeeper {
/* NTP adjusted clock multiplier */
u32 mult;

+ /* The current time */
+ struct timespec xtime;
/*
* 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
@@ -161,10 +163,6 @@ static inline s64 timekeeping_get_ns_raw(void)
__cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);


-/*
- * The current time
- */
-static struct timespec xtime __attribute__ ((aligned (16)));

/*
* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock.
@@ -177,10 +175,10 @@ int __read_mostly timekeeping_suspended;
/* must hold xtime_lock */
void timekeeping_leap_insert(int leapsecond)
{
- xtime.tv_sec += leapsecond;
+ timekeeper.xtime.tv_sec += leapsecond;
timekeeper.wall_to_monotonic.tv_sec -= leapsecond;
- update_vsyscall(&xtime, &timekeeper.wall_to_monotonic, timekeeper.clock,
- timekeeper.mult);
+ update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic,
+ timekeeper.clock, timekeeper.mult);
}

/**
@@ -207,7 +205,7 @@ static void timekeeping_forward_now(void)
/* If arch requires, add in gettimeoffset() */
nsec += arch_gettimeoffset();

- timespec_add_ns(&xtime, nsec);
+ timespec_add_ns(&timekeeper.xtime, nsec);

nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
timespec_add_ns(&raw_time, nsec);
@@ -229,7 +227,7 @@ void getnstimeofday(struct timespec *ts)
do {
seq = read_seqbegin(&xtime_lock);

- *ts = xtime;
+ *ts = timekeeper.xtime;
nsecs = timekeeping_get_ns();

/* If arch requires, add in gettimeoffset() */
@@ -251,8 +249,10 @@ ktime_t ktime_get(void)

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

} while (read_seqretry(&xtime_lock, seq));
@@ -282,7 +282,7 @@ void ktime_get_ts(struct timespec *ts)

do {
seq = read_seqbegin(&xtime_lock);
- *ts = xtime;
+ *ts = timekeeper.xtime;
tomono = timekeeper.wall_to_monotonic;
nsecs = timekeeping_get_ns();

@@ -317,7 +317,7 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real)
seq = read_seqbegin(&xtime_lock);

*ts_raw = raw_time;
- *ts_real = xtime;
+ *ts_real = timekeeper.xtime;

nsecs_raw = timekeeping_get_ns_raw();
nsecs_real = timekeeping_get_ns();
@@ -370,18 +370,18 @@ int do_settimeofday(const struct timespec *tv)

timekeeping_forward_now();

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

- xtime = *tv;
+ timekeeper.xtime = *tv;

timekeeper.ntp_error = 0;
ntp_clear();

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

write_sequnlock_irqrestore(&xtime_lock, flags);

@@ -411,15 +411,15 @@ int timekeeping_inject_offset(struct timespec *ts)

timekeeping_forward_now();

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

timekeeper.ntp_error = 0;
ntp_clear();

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

write_sequnlock_irqrestore(&xtime_lock, flags);

@@ -584,13 +584,13 @@ void __init timekeeping_init(void)
clock->enable(clock);
timekeeper_setup_internals(clock);

- xtime.tv_sec = now.tv_sec;
- xtime.tv_nsec = now.tv_nsec;
+ timekeeper.xtime.tv_sec = now.tv_sec;
+ timekeeper.xtime.tv_nsec = now.tv_nsec;
raw_time.tv_sec = 0;
raw_time.tv_nsec = 0;
if (boot.tv_sec == 0 && boot.tv_nsec == 0) {
- boot.tv_sec = xtime.tv_sec;
- boot.tv_nsec = xtime.tv_nsec;
+ boot.tv_sec = timekeeper.xtime.tv_sec;
+ boot.tv_nsec = timekeeper.xtime.tv_nsec;
}
set_normalized_timespec(&timekeeper.wall_to_monotonic,
-boot.tv_sec, -boot.tv_nsec);
@@ -617,7 +617,7 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta)
return;
}

- xtime = timespec_add(xtime, *delta);
+ timekeeper.xtime = timespec_add(timekeeper.xtime, *delta);
timekeeper.wall_to_monotonic =
timespec_sub(timekeeper.wall_to_monotonic, *delta);
timekeeper.total_sleep_time = timespec_add(
@@ -652,8 +652,8 @@ void timekeeping_inject_sleeptime(struct timespec *delta)

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

write_sequnlock_irqrestore(&xtime_lock, flags);

@@ -716,7 +716,7 @@ static int timekeeping_suspend(void)
* try to compensate so the difference in system time
* and persistent_clock time stays close to constant.
*/
- delta = timespec_sub(xtime, timekeeping_suspend_time);
+ delta = timespec_sub(timekeeper.xtime, timekeeping_suspend_time);
delta_delta = timespec_sub(delta, old_delta);
if (abs(delta_delta.tv_sec) >= 2) {
/*
@@ -862,7 +862,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
timekeeper.xtime_nsec += timekeeper.xtime_interval << shift;
while (timekeeper.xtime_nsec >= nsecps) {
timekeeper.xtime_nsec -= nsecps;
- xtime.tv_sec++;
+ timekeeper.xtime.tv_sec++;
second_overflow();
}

@@ -908,7 +908,8 @@ static void update_wall_time(void)
#else
offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
#endif
- timekeeper.xtime_nsec = (s64)xtime.tv_nsec << timekeeper.shift;
+ timekeeper.xtime_nsec = (s64)timekeeper.xtime.tv_nsec <<
+ timekeeper.shift;

/*
* With NO_HZ we may have to accumulate many cycle_intervals
@@ -959,8 +960,10 @@ static void update_wall_time(void)
* Store full nanoseconds into xtime after rounding it up and
* add the remainder to the error difference.
*/
- xtime.tv_nsec = ((s64) timekeeper.xtime_nsec >> timekeeper.shift) + 1;
- timekeeper.xtime_nsec -= (s64) xtime.tv_nsec << timekeeper.shift;
+ timekeeper.xtime.tv_nsec = ((s64)timekeeper.xtime_nsec >>
+ timekeeper.shift) + 1;
+ timekeeper.xtime_nsec -= (s64)timekeeper.xtime.tv_nsec <<
+ timekeeper.shift;
timekeeper.ntp_error += timekeeper.xtime_nsec <<
timekeeper.ntp_error_shift;

@@ -968,15 +971,15 @@ static void update_wall_time(void)
* Finally, make sure that after the rounding
* xtime.tv_nsec isn't larger then NSEC_PER_SEC
*/
- if (unlikely(xtime.tv_nsec >= NSEC_PER_SEC)) {
- xtime.tv_nsec -= NSEC_PER_SEC;
- xtime.tv_sec++;
+ if (unlikely(timekeeper.xtime.tv_nsec >= NSEC_PER_SEC)) {
+ timekeeper.xtime.tv_nsec -= NSEC_PER_SEC;
+ timekeeper.xtime.tv_sec++;
second_overflow();
}

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

/**
@@ -1023,7 +1026,7 @@ void get_monotonic_boottime(struct timespec *ts)

do {
seq = read_seqbegin(&xtime_lock);
- *ts = xtime;
+ *ts = timekeeper.xtime;
tomono = timekeeper.wall_to_monotonic;
sleep = timekeeper.total_sleep_time;
nsecs = timekeeping_get_ns();
@@ -1064,13 +1067,13 @@ EXPORT_SYMBOL_GPL(monotonic_to_bootbased);

unsigned long get_seconds(void)
{
- return xtime.tv_sec;
+ return timekeeper.xtime.tv_sec;
}
EXPORT_SYMBOL(get_seconds);

struct timespec __current_kernel_time(void)
{
- return xtime;
+ return timekeeper.xtime;
}

struct timespec current_kernel_time(void)
@@ -1081,7 +1084,7 @@ struct timespec current_kernel_time(void)
do {
seq = read_seqbegin(&xtime_lock);

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

return now;
@@ -1096,7 +1099,7 @@ struct timespec get_monotonic_coarse(void)
do {
seq = read_seqbegin(&xtime_lock);

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

@@ -1131,7 +1134,7 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,

do {
seq = read_seqbegin(&xtime_lock);
- *xtim = xtime;
+ *xtim = timekeeper.xtime;
*wtom = timekeeper.wall_to_monotonic;
*sleep = timekeeper.total_sleep_time;
} while (read_seqretry(&xtime_lock, seq));
--
1.7.3.2.146.gca209

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