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-rw-r--r--kernel/time/timekeeping.c511
1 files changed, 303 insertions, 208 deletions
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 6f46a00a1e8a..f045cc50832d 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -24,32 +24,32 @@
/* Structure holding internal timekeeping values. */
struct timekeeper {
/* Current clocksource used for timekeeping. */
- struct clocksource *clock;
+ struct clocksource *clock;
/* NTP adjusted clock multiplier */
- u32 mult;
+ 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;
+ cycle_t cycle_interval;
/* Number of clock shifted nano seconds in one NTP interval. */
- u64 xtime_interval;
+ u64 xtime_interval;
/* shifted nano seconds left over when rounding cycle_interval */
- s64 xtime_remainder;
+ s64 xtime_remainder;
/* Raw nano seconds accumulated per NTP interval. */
- u32 raw_interval;
+ u32 raw_interval;
+
+ /* Current CLOCK_REALTIME time in seconds */
+ u64 xtime_sec;
+ /* Clock shifted nano seconds */
+ u64 xtime_nsec;
- /* Clock shifted nano seconds remainder not stored in xtime.tv_nsec. */
- u64 xtime_nsec;
/* Difference between accumulated time and NTP time in ntp
* shifted nano seconds. */
- s64 ntp_error;
+ 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;
/*
* 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
@@ -64,14 +64,17 @@ struct timekeeper {
* - wall_to_monotonic is no longer the boot time, getboottime must be
* used instead.
*/
- struct timespec wall_to_monotonic;
+ struct timespec wall_to_monotonic;
/* time spent in suspend */
- struct timespec total_sleep_time;
+ struct timespec total_sleep_time;
/* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
- struct timespec raw_time;
-
+ struct timespec raw_time;
+ /* Offset clock monotonic -> clock realtime */
+ ktime_t offs_real;
+ /* Offset clock monotonic -> clock boottime */
+ ktime_t offs_boot;
/* Seqlock for all timekeeper values */
- seqlock_t lock;
+ seqlock_t lock;
};
static struct timekeeper timekeeper;
@@ -82,11 +85,37 @@ static struct timekeeper timekeeper;
*/
__cacheline_aligned_in_smp DEFINE_SEQLOCK(xtime_lock);
-
/* flag for if timekeeping is suspended */
int __read_mostly timekeeping_suspended;
+static inline void tk_normalize_xtime(struct timekeeper *tk)
+{
+ while (tk->xtime_nsec >= ((u64)NSEC_PER_SEC << tk->shift)) {
+ tk->xtime_nsec -= (u64)NSEC_PER_SEC << tk->shift;
+ tk->xtime_sec++;
+ }
+}
+
+static struct timespec tk_xtime(struct timekeeper *tk)
+{
+ struct timespec ts;
+
+ ts.tv_sec = tk->xtime_sec;
+ ts.tv_nsec = (long)(tk->xtime_nsec >> tk->shift);
+ return ts;
+}
+
+static void tk_set_xtime(struct timekeeper *tk, const struct timespec *ts)
+{
+ tk->xtime_sec = ts->tv_sec;
+ tk->xtime_nsec = ts->tv_nsec << tk->shift;
+}
+static void tk_xtime_add(struct timekeeper *tk, const struct timespec *ts)
+{
+ tk->xtime_sec += ts->tv_sec;
+ tk->xtime_nsec += ts->tv_nsec << tk->shift;
+}
/**
* timekeeper_setup_internals - Set up internals to use clocksource clock.
@@ -98,12 +127,14 @@ int __read_mostly timekeeping_suspended;
*
* Unless you're the timekeeping code, you should not be using this!
*/
-static void timekeeper_setup_internals(struct clocksource *clock)
+static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock)
{
cycle_t interval;
u64 tmp, ntpinterval;
+ struct clocksource *old_clock;
- timekeeper.clock = clock;
+ old_clock = tk->clock;
+ tk->clock = clock;
clock->cycle_last = clock->read(clock);
/* Do the ns -> cycle conversion first, using original mult */
@@ -116,71 +147,96 @@ static void timekeeper_setup_internals(struct clocksource *clock)
tmp = 1;
interval = (cycle_t) tmp;
- timekeeper.cycle_interval = interval;
+ tk->cycle_interval = interval;
/* Go back from cycles -> shifted ns */
- timekeeper.xtime_interval = (u64) interval * clock->mult;
- timekeeper.xtime_remainder = ntpinterval - timekeeper.xtime_interval;
- timekeeper.raw_interval =
+ tk->xtime_interval = (u64) interval * clock->mult;
+ tk->xtime_remainder = ntpinterval - tk->xtime_interval;
+ tk->raw_interval =
((u64) interval * clock->mult) >> clock->shift;
- timekeeper.xtime_nsec = 0;
- timekeeper.shift = clock->shift;
+ /* if changing clocks, convert xtime_nsec shift units */
+ if (old_clock) {
+ int shift_change = clock->shift - old_clock->shift;
+ if (shift_change < 0)
+ tk->xtime_nsec >>= -shift_change;
+ else
+ tk->xtime_nsec <<= shift_change;
+ }
+ tk->shift = clock->shift;
- timekeeper.ntp_error = 0;
- timekeeper.ntp_error_shift = NTP_SCALE_SHIFT - clock->shift;
+ tk->ntp_error = 0;
+ tk->ntp_error_shift = NTP_SCALE_SHIFT - clock->shift;
/*
* The timekeeper keeps its own mult values for the currently
* active clocksource. These value will be adjusted via NTP
* to counteract clock drifting.
*/
- timekeeper.mult = clock->mult;
+ tk->mult = clock->mult;
}
/* Timekeeper helper functions. */
-static inline s64 timekeeping_get_ns(void)
+static inline s64 timekeeping_get_ns(struct timekeeper *tk)
{
cycle_t cycle_now, cycle_delta;
struct clocksource *clock;
+ s64 nsec;
/* read clocksource: */
- clock = timekeeper.clock;
+ clock = tk->clock;
cycle_now = clock->read(clock);
/* calculate the delta since the last update_wall_time: */
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
- /* return delta convert to nanoseconds using ntp adjusted mult. */
- return clocksource_cyc2ns(cycle_delta, timekeeper.mult,
- timekeeper.shift);
+ nsec = cycle_delta * tk->mult + tk->xtime_nsec;
+ nsec >>= tk->shift;
+
+ /* If arch requires, add in gettimeoffset() */
+ return nsec + arch_gettimeoffset();
}
-static inline s64 timekeeping_get_ns_raw(void)
+static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk)
{
cycle_t cycle_now, cycle_delta;
struct clocksource *clock;
+ s64 nsec;
/* read clocksource: */
- clock = timekeeper.clock;
+ clock = tk->clock;
cycle_now = clock->read(clock);
/* calculate the delta since the last update_wall_time: */
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
- /* return delta convert to nanoseconds. */
- return clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
+ /* convert delta to nanoseconds. */
+ nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
+
+ /* If arch requires, add in gettimeoffset() */
+ return nsec + arch_gettimeoffset();
+}
+
+static void update_rt_offset(struct timekeeper *tk)
+{
+ struct timespec tmp, *wtm = &tk->wall_to_monotonic;
+
+ set_normalized_timespec(&tmp, -wtm->tv_sec, -wtm->tv_nsec);
+ tk->offs_real = timespec_to_ktime(tmp);
}
/* must hold write on timekeeper.lock */
-static void timekeeping_update(bool clearntp)
+static void timekeeping_update(struct timekeeper *tk, bool clearntp)
{
+ struct timespec xt;
+
if (clearntp) {
- timekeeper.ntp_error = 0;
+ tk->ntp_error = 0;
ntp_clear();
}
- update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic,
- timekeeper.clock, timekeeper.mult);
+ update_rt_offset(tk);
+ xt = tk_xtime(tk);
+ update_vsyscall(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult);
}
@@ -191,27 +247,26 @@ static void timekeeping_update(bool clearntp)
* update_wall_time(). This is useful before significant clock changes,
* as it avoids having to deal with this time offset explicitly.
*/
-static void timekeeping_forward_now(void)
+static void timekeeping_forward_now(struct timekeeper *tk)
{
cycle_t cycle_now, cycle_delta;
struct clocksource *clock;
s64 nsec;
- clock = timekeeper.clock;
+ clock = tk->clock;
cycle_now = clock->read(clock);
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
clock->cycle_last = cycle_now;
- nsec = clocksource_cyc2ns(cycle_delta, timekeeper.mult,
- timekeeper.shift);
+ tk->xtime_nsec += cycle_delta * tk->mult;
/* If arch requires, add in gettimeoffset() */
- nsec += arch_gettimeoffset();
+ tk->xtime_nsec += arch_gettimeoffset() << tk->shift;
- timespec_add_ns(&timekeeper.xtime, nsec);
+ tk_normalize_xtime(tk);
nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
- timespec_add_ns(&timekeeper.raw_time, nsec);
+ timespec_add_ns(&tk->raw_time, nsec);
}
/**
@@ -223,18 +278,15 @@ static void timekeeping_forward_now(void)
void getnstimeofday(struct timespec *ts)
{
unsigned long seq;
- s64 nsecs;
+ s64 nsecs = 0;
WARN_ON(timekeeping_suspended);
do {
seq = read_seqbegin(&timekeeper.lock);
- *ts = timekeeper.xtime;
- nsecs = timekeeping_get_ns();
-
- /* If arch requires, add in gettimeoffset() */
- nsecs += arch_gettimeoffset();
+ ts->tv_sec = timekeeper.xtime_sec;
+ ts->tv_nsec = timekeeping_get_ns(&timekeeper);
} while (read_seqretry(&timekeeper.lock, seq));
@@ -251,13 +303,10 @@ ktime_t ktime_get(void)
do {
seq = read_seqbegin(&timekeeper.lock);
- secs = timekeeper.xtime.tv_sec +
+ secs = timekeeper.xtime_sec +
timekeeper.wall_to_monotonic.tv_sec;
- nsecs = timekeeper.xtime.tv_nsec +
+ nsecs = timekeeping_get_ns(&timekeeper) +
timekeeper.wall_to_monotonic.tv_nsec;
- nsecs += timekeeping_get_ns();
- /* If arch requires, add in gettimeoffset() */
- nsecs += arch_gettimeoffset();
} while (read_seqretry(&timekeeper.lock, seq));
/*
@@ -280,22 +329,19 @@ void ktime_get_ts(struct timespec *ts)
{
struct timespec tomono;
unsigned int seq;
- s64 nsecs;
WARN_ON(timekeeping_suspended);
do {
seq = read_seqbegin(&timekeeper.lock);
- *ts = timekeeper.xtime;
+ ts->tv_sec = timekeeper.xtime_sec;
+ ts->tv_nsec = timekeeping_get_ns(&timekeeper);
tomono = timekeeper.wall_to_monotonic;
- nsecs = timekeeping_get_ns();
- /* If arch requires, add in gettimeoffset() */
- nsecs += arch_gettimeoffset();
} while (read_seqretry(&timekeeper.lock, seq));
set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec,
- ts->tv_nsec + tomono.tv_nsec + nsecs);
+ ts->tv_nsec + tomono.tv_nsec);
}
EXPORT_SYMBOL_GPL(ktime_get_ts);
@@ -318,20 +364,14 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real)
WARN_ON_ONCE(timekeeping_suspended);
do {
- u32 arch_offset;
-
seq = read_seqbegin(&timekeeper.lock);
*ts_raw = timekeeper.raw_time;
- *ts_real = timekeeper.xtime;
-
- nsecs_raw = timekeeping_get_ns_raw();
- nsecs_real = timekeeping_get_ns();
+ ts_real->tv_sec = timekeeper.xtime_sec;
+ ts_real->tv_nsec = 0;
- /* If arch requires, add in gettimeoffset() */
- arch_offset = arch_gettimeoffset();
- nsecs_raw += arch_offset;
- nsecs_real += arch_offset;
+ nsecs_raw = timekeeping_get_ns_raw(&timekeeper);
+ nsecs_real = timekeeping_get_ns(&timekeeper);
} while (read_seqretry(&timekeeper.lock, seq));
@@ -366,7 +406,7 @@ EXPORT_SYMBOL(do_gettimeofday);
*/
int do_settimeofday(const struct timespec *tv)
{
- struct timespec ts_delta;
+ struct timespec ts_delta, xt;
unsigned long flags;
if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
@@ -374,15 +414,18 @@ int do_settimeofday(const struct timespec *tv)
write_seqlock_irqsave(&timekeeper.lock, flags);
- timekeeping_forward_now();
+ timekeeping_forward_now(&timekeeper);
+
+ xt = tk_xtime(&timekeeper);
+ ts_delta.tv_sec = tv->tv_sec - xt.tv_sec;
+ ts_delta.tv_nsec = tv->tv_nsec - xt.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);
- timekeeper.xtime = *tv;
- timekeeping_update(true);
+ tk_set_xtime(&timekeeper, tv);
+
+ timekeeping_update(&timekeeper, true);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
@@ -409,13 +452,14 @@ int timekeeping_inject_offset(struct timespec *ts)
write_seqlock_irqsave(&timekeeper.lock, flags);
- timekeeping_forward_now();
+ timekeeping_forward_now(&timekeeper);
- timekeeper.xtime = timespec_add(timekeeper.xtime, *ts);
+
+ tk_xtime_add(&timekeeper, ts);
timekeeper.wall_to_monotonic =
timespec_sub(timekeeper.wall_to_monotonic, *ts);
- timekeeping_update(true);
+ timekeeping_update(&timekeeper, true);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
@@ -440,14 +484,14 @@ static int change_clocksource(void *data)
write_seqlock_irqsave(&timekeeper.lock, flags);
- timekeeping_forward_now();
+ timekeeping_forward_now(&timekeeper);
if (!new->enable || new->enable(new) == 0) {
old = timekeeper.clock;
- timekeeper_setup_internals(new);
+ tk_setup_internals(&timekeeper, new);
if (old->disable)
old->disable(old);
}
- timekeeping_update(true);
+ timekeeping_update(&timekeeper, true);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
@@ -497,7 +541,7 @@ void getrawmonotonic(struct timespec *ts)
do {
seq = read_seqbegin(&timekeeper.lock);
- nsecs = timekeeping_get_ns_raw();
+ nsecs = timekeeping_get_ns_raw(&timekeeper);
*ts = timekeeper.raw_time;
} while (read_seqretry(&timekeeper.lock, seq));
@@ -532,6 +576,7 @@ u64 timekeeping_max_deferment(void)
{
unsigned long seq;
u64 ret;
+
do {
seq = read_seqbegin(&timekeeper.lock);
@@ -592,18 +637,17 @@ void __init timekeeping_init(void)
clock = clocksource_default_clock();
if (clock->enable)
clock->enable(clock);
- timekeeper_setup_internals(clock);
+ tk_setup_internals(&timekeeper, clock);
- timekeeper.xtime.tv_sec = now.tv_sec;
- timekeeper.xtime.tv_nsec = now.tv_nsec;
+ tk_set_xtime(&timekeeper, &now);
timekeeper.raw_time.tv_sec = 0;
timekeeper.raw_time.tv_nsec = 0;
- if (boot.tv_sec == 0 && boot.tv_nsec == 0) {
- boot.tv_sec = timekeeper.xtime.tv_sec;
- boot.tv_nsec = timekeeper.xtime.tv_nsec;
- }
+ if (boot.tv_sec == 0 && boot.tv_nsec == 0)
+ boot = tk_xtime(&timekeeper);
+
set_normalized_timespec(&timekeeper.wall_to_monotonic,
-boot.tv_sec, -boot.tv_nsec);
+ update_rt_offset(&timekeeper);
timekeeper.total_sleep_time.tv_sec = 0;
timekeeper.total_sleep_time.tv_nsec = 0;
write_sequnlock_irqrestore(&timekeeper.lock, flags);
@@ -612,6 +656,12 @@ void __init timekeeping_init(void)
/* time in seconds when suspend began */
static struct timespec timekeeping_suspend_time;
+static void update_sleep_time(struct timespec t)
+{
+ timekeeper.total_sleep_time = t;
+ timekeeper.offs_boot = timespec_to_ktime(t);
+}
+
/**
* __timekeeping_inject_sleeptime - Internal function to add sleep interval
* @delta: pointer to a timespec delta value
@@ -619,7 +669,8 @@ static struct timespec timekeeping_suspend_time;
* Takes a timespec offset measuring a suspend interval and properly
* adds the sleep offset to the timekeeping variables.
*/
-static void __timekeeping_inject_sleeptime(struct timespec *delta)
+static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
+ struct timespec *delta)
{
if (!timespec_valid(delta)) {
printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid "
@@ -627,11 +678,9 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta)
return;
}
- timekeeper.xtime = timespec_add(timekeeper.xtime, *delta);
- timekeeper.wall_to_monotonic =
- timespec_sub(timekeeper.wall_to_monotonic, *delta);
- timekeeper.total_sleep_time = timespec_add(
- timekeeper.total_sleep_time, *delta);
+ tk_xtime_add(tk, delta);
+ tk->wall_to_monotonic = timespec_sub(tk->wall_to_monotonic, *delta);
+ update_sleep_time(timespec_add(tk->total_sleep_time, *delta));
}
@@ -657,11 +706,11 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
write_seqlock_irqsave(&timekeeper.lock, flags);
- timekeeping_forward_now();
+ timekeeping_forward_now(&timekeeper);
- __timekeeping_inject_sleeptime(delta);
+ __timekeeping_inject_sleeptime(&timekeeper, delta);
- timekeeping_update(true);
+ timekeeping_update(&timekeeper, true);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
@@ -690,12 +739,13 @@ static void timekeeping_resume(void)
if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) {
ts = timespec_sub(ts, timekeeping_suspend_time);
- __timekeeping_inject_sleeptime(&ts);
+ __timekeeping_inject_sleeptime(&timekeeper, &ts);
}
/* re-base the last cycle value */
timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
timekeeper.ntp_error = 0;
timekeeping_suspended = 0;
+ timekeeping_update(&timekeeper, false);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
touch_softlockup_watchdog();
@@ -715,7 +765,7 @@ static int timekeeping_suspend(void)
read_persistent_clock(&timekeeping_suspend_time);
write_seqlock_irqsave(&timekeeper.lock, flags);
- timekeeping_forward_now();
+ timekeeping_forward_now(&timekeeper);
timekeeping_suspended = 1;
/*
@@ -724,7 +774,7 @@ 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(timekeeper.xtime, timekeeping_suspend_time);
+ delta = timespec_sub(tk_xtime(&timekeeper), timekeeping_suspend_time);
delta_delta = timespec_sub(delta, old_delta);
if (abs(delta_delta.tv_sec) >= 2) {
/*
@@ -763,7 +813,8 @@ device_initcall(timekeeping_init_ops);
* If the error is already larger, we look ahead even further
* to compensate for late or lost adjustments.
*/
-static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,
+static __always_inline int timekeeping_bigadjust(struct timekeeper *tk,
+ s64 error, s64 *interval,
s64 *offset)
{
s64 tick_error, i;
@@ -779,7 +830,7 @@ static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,
* here. This is tuned so that an error of about 1 msec is adjusted
* within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks).
*/
- error2 = timekeeper.ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);
+ error2 = tk->ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ);
error2 = abs(error2);
for (look_ahead = 0; error2 > 0; look_ahead++)
error2 >>= 2;
@@ -788,8 +839,8 @@ 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 = ntp_tick_length() >> (timekeeper.ntp_error_shift + 1);
- tick_error -= timekeeper.xtime_interval >> 1;
+ tick_error = ntp_tick_length() >> (tk->ntp_error_shift + 1);
+ tick_error -= tk->xtime_interval >> 1;
error = ((error - tick_error) >> look_ahead) + tick_error;
/* Finally calculate the adjustment shift value. */
@@ -814,9 +865,9 @@ static __always_inline int timekeeping_bigadjust(s64 error, s64 *interval,
* this is optimized for the most common adjustments of -1,0,1,
* for other values we can do a bit more work.
*/
-static void timekeeping_adjust(s64 offset)
+static void timekeeping_adjust(struct timekeeper *tk, s64 offset)
{
- s64 error, interval = timekeeper.cycle_interval;
+ s64 error, interval = tk->cycle_interval;
int adj;
/*
@@ -832,7 +883,7 @@ static void timekeeping_adjust(s64 offset)
*
* Note: It does not "save" on aggravation when reading the code.
*/
- error = timekeeper.ntp_error >> (timekeeper.ntp_error_shift - 1);
+ error = tk->ntp_error >> (tk->ntp_error_shift - 1);
if (error > interval) {
/*
* We now divide error by 4(via shift), which checks if
@@ -854,7 +905,8 @@ static void timekeeping_adjust(s64 offset)
if (likely(error <= interval))
adj = 1;
else
- adj = timekeeping_bigadjust(error, &interval, &offset);
+ adj = timekeeping_bigadjust(tk, error, &interval,
+ &offset);
} else if (error < -interval) {
/* See comment above, this is just switched for the negative */
error >>= 2;
@@ -863,18 +915,17 @@ static void timekeeping_adjust(s64 offset)
interval = -interval;
offset = -offset;
} else
- adj = timekeeping_bigadjust(error, &interval, &offset);
- } else /* No adjustment needed */
+ adj = timekeeping_bigadjust(tk, error, &interval,
+ &offset);
+ } else
return;
- if (unlikely(timekeeper.clock->maxadj &&
- (timekeeper.mult + adj >
- timekeeper.clock->mult + timekeeper.clock->maxadj))) {
+ if (unlikely(tk->clock->maxadj &&
+ (tk->mult + adj > tk->clock->mult + tk->clock->maxadj))) {
printk_once(KERN_WARNING
"Adjusting %s more than 11%% (%ld vs %ld)\n",
- timekeeper.clock->name, (long)timekeeper.mult + adj,
- (long)timekeeper.clock->mult +
- timekeeper.clock->maxadj);
+ tk->clock->name, (long)tk->mult + adj,
+ (long)tk->clock->mult + tk->clock->maxadj);
}
/*
* So the following can be confusing.
@@ -925,11 +976,60 @@ static void timekeeping_adjust(s64 offset)
*
* XXX - TODO: Doc ntp_error calculation.
*/
- timekeeper.mult += adj;
- timekeeper.xtime_interval += interval;
- timekeeper.xtime_nsec -= offset;
- timekeeper.ntp_error -= (interval - offset) <<
- timekeeper.ntp_error_shift;
+ tk->mult += adj;
+ tk->xtime_interval += interval;
+ tk->xtime_nsec -= offset;
+ tk->ntp_error -= (interval - offset) << tk->ntp_error_shift;
+
+ /*
+ * It may be possible that when we entered this function, xtime_nsec
+ * was very small. Further, if we're slightly speeding the clocksource
+ * in the code above, its possible the required corrective factor to
+ * xtime_nsec could cause it to underflow.
+ *
+ * Now, since we already accumulated the second, cannot simply roll
+ * the accumulated second back, since the NTP subsystem has been
+ * notified via second_overflow. So instead we push xtime_nsec forward
+ * by the amount we underflowed, and add that amount into the error.
+ *
+ * We'll correct this error next time through this function, when
+ * xtime_nsec is not as small.
+ */
+ if (unlikely((s64)tk->xtime_nsec < 0)) {
+ s64 neg = -(s64)tk->xtime_nsec;
+ tk->xtime_nsec = 0;
+ tk->ntp_error += neg << tk->ntp_error_shift;
+ }
+
+}
+
+
+/**
+ * accumulate_nsecs_to_secs - Accumulates nsecs into secs
+ *
+ * Helper function that accumulates a the nsecs greater then a second
+ * from the xtime_nsec field to the xtime_secs field.
+ * It also calls into the NTP code to handle leapsecond processing.
+ *
+ */
+static inline void accumulate_nsecs_to_secs(struct timekeeper *tk)
+{
+ u64 nsecps = (u64)NSEC_PER_SEC << tk->shift;
+
+ while (tk->xtime_nsec >= nsecps) {
+ int leap;
+
+ tk->xtime_nsec -= nsecps;
+ tk->xtime_sec++;
+
+ /* Figure out if its a leap sec and apply if needed */
+ leap = second_overflow(tk->xtime_sec);
+ tk->xtime_sec += leap;
+ tk->wall_to_monotonic.tv_sec -= leap;
+ if (leap)
+ clock_was_set_delayed();
+
+ }
}
@@ -942,44 +1042,36 @@ 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(struct timekeeper *tk, cycle_t offset,
+ u32 shift)
{
- u64 nsecps = (u64)NSEC_PER_SEC << timekeeper.shift;
u64 raw_nsecs;
- /* If the offset is smaller than a shifted interval, do nothing */
- if (offset < timekeeper.cycle_interval<<shift)
+ /* If the offset is smaller then a shifted interval, do nothing */
+ if (offset < tk->cycle_interval<<shift)
return offset;
/* Accumulate one shifted interval */
- offset -= timekeeper.cycle_interval << shift;
- timekeeper.clock->cycle_last += timekeeper.cycle_interval << shift;
+ offset -= tk->cycle_interval << shift;
+ tk->clock->cycle_last += tk->cycle_interval << shift;
- timekeeper.xtime_nsec += timekeeper.xtime_interval << shift;
- while (timekeeper.xtime_nsec >= nsecps) {
- int leap;
- timekeeper.xtime_nsec -= nsecps;
- timekeeper.xtime.tv_sec++;
- leap = second_overflow(timekeeper.xtime.tv_sec);
- timekeeper.xtime.tv_sec += leap;
- timekeeper.wall_to_monotonic.tv_sec -= leap;
- }
+ tk->xtime_nsec += tk->xtime_interval << shift;
+ accumulate_nsecs_to_secs(tk);
/* Accumulate raw time */
- raw_nsecs = timekeeper.raw_interval << shift;
- raw_nsecs += timekeeper.raw_time.tv_nsec;
+ raw_nsecs = tk->raw_interval << shift;
+ raw_nsecs += tk->raw_time.tv_nsec;
if (raw_nsecs >= NSEC_PER_SEC) {
u64 raw_secs = raw_nsecs;
raw_nsecs = do_div(raw_secs, NSEC_PER_SEC);
- timekeeper.raw_time.tv_sec += raw_secs;
+ tk->raw_time.tv_sec += raw_secs;
}
- timekeeper.raw_time.tv_nsec = raw_nsecs;
+ tk->raw_time.tv_nsec = raw_nsecs;
/* Accumulate error between NTP and clock interval */
- timekeeper.ntp_error += ntp_tick_length() << shift;
- timekeeper.ntp_error -=
- (timekeeper.xtime_interval + timekeeper.xtime_remainder) <<
- (timekeeper.ntp_error_shift + shift);
+ tk->ntp_error += ntp_tick_length() << shift;
+ tk->ntp_error -= (tk->xtime_interval + tk->xtime_remainder) <<
+ (tk->ntp_error_shift + shift);
return offset;
}
@@ -995,6 +1087,7 @@ static void update_wall_time(void)
cycle_t offset;
int shift = 0, maxshift;
unsigned long flags;
+ s64 remainder;
write_seqlock_irqsave(&timekeeper.lock, flags);
@@ -1009,8 +1102,6 @@ static void update_wall_time(void)
#else
offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
#endif
- timekeeper.xtime_nsec = (s64)timekeeper.xtime.tv_nsec <<
- timekeeper.shift;
/*
* With NO_HZ we may have to accumulate many cycle_intervals
@@ -1026,62 +1117,36 @@ static void update_wall_time(void)
maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1;
shift = min(shift, maxshift);
while (offset >= timekeeper.cycle_interval) {
- offset = logarithmic_accumulation(offset, shift);
+ offset = logarithmic_accumulation(&timekeeper, offset, shift);
if(offset < timekeeper.cycle_interval<<shift)
shift--;
}
/* correct the clock when NTP error is too big */
- timekeeping_adjust(offset);
-
- /*
- * Since in the loop above, we accumulate any amount of time
- * in xtime_nsec over a second into xtime.tv_sec, its possible for
- * xtime_nsec to be fairly small after the loop. Further, if we're
- * slightly speeding the clocksource up in timekeeping_adjust(),
- * its possible the required corrective factor to xtime_nsec could
- * cause it to underflow.
- *
- * Now, we cannot simply roll the accumulated second back, since
- * the NTP subsystem has been notified via second_overflow. So
- * instead we push xtime_nsec forward by the amount we underflowed,
- * and add that amount into the error.
- *
- * We'll correct this error next time through this function, when
- * xtime_nsec is not as small.
- */
- if (unlikely((s64)timekeeper.xtime_nsec < 0)) {
- s64 neg = -(s64)timekeeper.xtime_nsec;
- timekeeper.xtime_nsec = 0;
- timekeeper.ntp_error += neg << timekeeper.ntp_error_shift;
- }
+ timekeeping_adjust(&timekeeper, offset);
/*
- * Store full nanoseconds into xtime after rounding it up and
- * add the remainder to the error difference.
- */
- 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;
+ * Store only full nanoseconds into xtime_nsec after rounding
+ * it up and add the remainder to the error difference.
+ * XXX - This is necessary to avoid small 1ns inconsistnecies caused
+ * by truncating the remainder in vsyscalls. However, it causes
+ * additional work to be done in timekeeping_adjust(). Once
+ * the vsyscall implementations are converted to use xtime_nsec
+ * (shifted nanoseconds), this can be killed.
+ */
+ remainder = timekeeper.xtime_nsec & ((1 << timekeeper.shift) - 1);
+ timekeeper.xtime_nsec -= remainder;
+ timekeeper.xtime_nsec += 1 << timekeeper.shift;
+ timekeeper.ntp_error += remainder << timekeeper.ntp_error_shift;
/*
* Finally, make sure that after the rounding
- * xtime.tv_nsec isn't larger than NSEC_PER_SEC
+ * xtime_nsec isn't larger than NSEC_PER_SEC
*/
- if (unlikely(timekeeper.xtime.tv_nsec >= NSEC_PER_SEC)) {
- int leap;
- timekeeper.xtime.tv_nsec -= NSEC_PER_SEC;
- timekeeper.xtime.tv_sec++;
- leap = second_overflow(timekeeper.xtime.tv_sec);
- timekeeper.xtime.tv_sec += leap;
- timekeeper.wall_to_monotonic.tv_sec -= leap;
- }
+ accumulate_nsecs_to_secs(&timekeeper);
- timekeeping_update(false);
+ timekeeping_update(&timekeeper, false);
out:
write_sequnlock_irqrestore(&timekeeper.lock, flags);
@@ -1126,21 +1191,20 @@ void get_monotonic_boottime(struct timespec *ts)
{
struct timespec tomono, sleep;
unsigned int seq;
- s64 nsecs;
WARN_ON(timekeeping_suspended);
do {
seq = read_seqbegin(&timekeeper.lock);
- *ts = timekeeper.xtime;
+ ts->tv_sec = timekeeper.xtime_sec;
+ ts->tv_nsec = timekeeping_get_ns(&timekeeper);
tomono = timekeeper.wall_to_monotonic;
sleep = timekeeper.total_sleep_time;
- nsecs = timekeeping_get_ns();
} while (read_seqretry(&timekeeper.lock, seq));
set_normalized_timespec(ts, ts->tv_sec + tomono.tv_sec + sleep.tv_sec,
- ts->tv_nsec + tomono.tv_nsec + sleep.tv_nsec + nsecs);
+ ts->tv_nsec + tomono.tv_nsec + sleep.tv_nsec);
}
EXPORT_SYMBOL_GPL(get_monotonic_boottime);
@@ -1173,13 +1237,13 @@ EXPORT_SYMBOL_GPL(monotonic_to_bootbased);
unsigned long get_seconds(void)
{
- return timekeeper.xtime.tv_sec;
+ return timekeeper.xtime_sec;
}
EXPORT_SYMBOL(get_seconds);
struct timespec __current_kernel_time(void)
{
- return timekeeper.xtime;
+ return tk_xtime(&timekeeper);
}
struct timespec current_kernel_time(void)
@@ -1190,7 +1254,7 @@ struct timespec current_kernel_time(void)
do {
seq = read_seqbegin(&timekeeper.lock);
- now = timekeeper.xtime;
+ now = tk_xtime(&timekeeper);
} while (read_seqretry(&timekeeper.lock, seq));
return now;
@@ -1205,7 +1269,7 @@ struct timespec get_monotonic_coarse(void)
do {
seq = read_seqbegin(&timekeeper.lock);
- now = timekeeper.xtime;
+ now = tk_xtime(&timekeeper);
mono = timekeeper.wall_to_monotonic;
} while (read_seqretry(&timekeeper.lock, seq));
@@ -1240,12 +1304,43 @@ void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim,
do {
seq = read_seqbegin(&timekeeper.lock);
- *xtim = timekeeper.xtime;
+ *xtim = tk_xtime(&timekeeper);
*wtom = timekeeper.wall_to_monotonic;
*sleep = timekeeper.total_sleep_time;
} while (read_seqretry(&timekeeper.lock, seq));
}
+#ifdef CONFIG_HIGH_RES_TIMERS
+/**
+ * ktime_get_update_offsets - hrtimer helper
+ * @offs_real: pointer to storage for monotonic -> realtime offset
+ * @offs_boot: pointer to storage for monotonic -> boottime offset
+ *
+ * Returns current monotonic time and updates the offsets
+ * Called from hrtimer_interupt() or retrigger_next_event()
+ */
+ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot)
+{
+ ktime_t now;
+ unsigned int seq;
+ u64 secs, nsecs;
+
+ do {
+ seq = read_seqbegin(&timekeeper.lock);
+
+ secs = timekeeper.xtime_sec;
+ nsecs = timekeeping_get_ns(&timekeeper);
+
+ *offs_real = timekeeper.offs_real;
+ *offs_boot = timekeeper.offs_boot;
+ } while (read_seqretry(&timekeeper.lock, seq));
+
+ now = ktime_add_ns(ktime_set(secs, 0), nsecs);
+ now = ktime_sub(now, *offs_real);
+ return now;
+}
+#endif
+
/**
* ktime_get_monotonic_offset() - get wall_to_monotonic in ktime_t format
*/