2 * linux/kernel/time/timekeeping.c
4 * Kernel timekeeping code and accessor functions
6 * This code was moved from linux/kernel/timer.c.
7 * Please see that file for copyright and history logs.
11 #include <linux/module.h>
12 #include <linux/interrupt.h>
13 #include <linux/percpu.h>
14 #include <linux/init.h>
16 #include <linux/sched.h>
17 #include <linux/sysdev.h>
18 #include <linux/clocksource.h>
19 #include <linux/jiffies.h>
20 #include <linux/time.h>
21 #include <linux/tick.h>
22 #include <linux/stop_machine.h>
24 /* Structure holding internal timekeeping values. */
26 /* Current clocksource used for timekeeping. */
27 struct clocksource
*clock
;
28 /* The shift value of the current clocksource. */
31 /* Number of clock cycles in one NTP interval. */
32 cycle_t cycle_interval
;
33 /* Number of clock shifted nano seconds in one NTP interval. */
35 /* Raw nano seconds accumulated per NTP interval. */
38 /* Clock shifted nano seconds remainder not stored in xtime.tv_nsec. */
40 /* Difference between accumulated time and NTP time in ntp
41 * shifted nano seconds. */
43 /* Shift conversion between clock shifted nano seconds and
44 * ntp shifted nano seconds. */
46 /* NTP adjusted clock multiplier */
50 struct timekeeper timekeeper
;
53 * timekeeper_setup_internals - Set up internals to use clocksource clock.
55 * @clock: Pointer to clocksource.
57 * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment
58 * pair and interval request.
60 * Unless you're the timekeeping code, you should not be using this!
62 static void timekeeper_setup_internals(struct clocksource
*clock
)
67 timekeeper
.clock
= clock
;
68 clock
->cycle_last
= clock
->read(clock
);
70 /* Do the ns -> cycle conversion first, using original mult */
71 tmp
= NTP_INTERVAL_LENGTH
;
74 do_div(tmp
, clock
->mult
);
78 interval
= (cycle_t
) tmp
;
79 timekeeper
.cycle_interval
= interval
;
81 /* Go back from cycles -> shifted ns */
82 timekeeper
.xtime_interval
= (u64
) interval
* clock
->mult
;
83 timekeeper
.raw_interval
=
84 ((u64
) interval
* clock
->mult
) >> clock
->shift
;
86 timekeeper
.xtime_nsec
= 0;
87 timekeeper
.shift
= clock
->shift
;
89 timekeeper
.ntp_error
= 0;
90 timekeeper
.ntp_error_shift
= NTP_SCALE_SHIFT
- clock
->shift
;
93 * The timekeeper keeps its own mult values for the currently
94 * active clocksource. These value will be adjusted via NTP
95 * to counteract clock drifting.
97 timekeeper
.mult
= clock
->mult
;
100 /* Timekeeper helper functions. */
101 static inline s64
timekeeping_get_ns(void)
103 cycle_t cycle_now
, cycle_delta
;
104 struct clocksource
*clock
;
106 /* read clocksource: */
107 clock
= timekeeper
.clock
;
108 cycle_now
= clock
->read(clock
);
110 /* calculate the delta since the last update_wall_time: */
111 cycle_delta
= (cycle_now
- clock
->cycle_last
) & clock
->mask
;
113 /* return delta convert to nanoseconds using ntp adjusted mult. */
114 return clocksource_cyc2ns(cycle_delta
, timekeeper
.mult
,
118 static inline s64
timekeeping_get_ns_raw(void)
120 cycle_t cycle_now
, cycle_delta
;
121 struct clocksource
*clock
;
123 /* read clocksource: */
124 clock
= timekeeper
.clock
;
125 cycle_now
= clock
->read(clock
);
127 /* calculate the delta since the last update_wall_time: */
128 cycle_delta
= (cycle_now
- clock
->cycle_last
) & clock
->mask
;
130 /* return delta convert to nanoseconds using ntp adjusted mult. */
131 return clocksource_cyc2ns(cycle_delta
, clock
->mult
, clock
->shift
);
135 * This read-write spinlock protects us from races in SMP while
136 * playing with xtime.
138 __cacheline_aligned_in_smp
DEFINE_SEQLOCK(xtime_lock
);
143 * wall_to_monotonic is what we need to add to xtime (or xtime corrected
144 * for sub jiffie times) to get to monotonic time. Monotonic is pegged
145 * at zero at system boot time, so wall_to_monotonic will be negative,
146 * however, we will ALWAYS keep the tv_nsec part positive so we can use
147 * the usual normalization.
149 * wall_to_monotonic is moved after resume from suspend for the monotonic
150 * time not to jump. We need to add total_sleep_time to wall_to_monotonic
151 * to get the real boot based time offset.
153 * - wall_to_monotonic is no longer the boot time, getboottime must be
156 static struct timespec xtime
__attribute__ ((aligned (16)));
157 static struct timespec wall_to_monotonic
__attribute__ ((aligned (16)));
158 static struct timespec total_sleep_time
;
161 * The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock.
163 struct timespec raw_time
;
165 /* flag for if timekeeping is suspended */
166 int __read_mostly timekeeping_suspended
;
168 /* must hold xtime_lock */
169 void timekeeping_leap_insert(int leapsecond
)
171 xtime
.tv_sec
+= leapsecond
;
172 wall_to_monotonic
.tv_sec
-= leapsecond
;
173 update_vsyscall(&xtime
, &wall_to_monotonic
, timekeeper
.clock
,
178 * timekeeping_forward_now - update clock to the current time
180 * Forward the current clock to update its state since the last call to
181 * update_wall_time(). This is useful before significant clock changes,
182 * as it avoids having to deal with this time offset explicitly.
184 static void timekeeping_forward_now(void)
186 cycle_t cycle_now
, cycle_delta
;
187 struct clocksource
*clock
;
190 clock
= timekeeper
.clock
;
191 cycle_now
= clock
->read(clock
);
192 cycle_delta
= (cycle_now
- clock
->cycle_last
) & clock
->mask
;
193 clock
->cycle_last
= cycle_now
;
195 nsec
= clocksource_cyc2ns(cycle_delta
, timekeeper
.mult
,
198 /* If arch requires, add in gettimeoffset() */
199 nsec
+= arch_gettimeoffset();
201 timespec_add_ns(&xtime
, nsec
);
203 nsec
= clocksource_cyc2ns(cycle_delta
, clock
->mult
, clock
->shift
);
204 timespec_add_ns(&raw_time
, nsec
);
208 * getnstimeofday - Returns the time of day in a timespec
209 * @ts: pointer to the timespec to be set
211 * Returns the time of day in a timespec.
213 void getnstimeofday(struct timespec
*ts
)
218 WARN_ON(timekeeping_suspended
);
221 seq
= read_seqbegin(&xtime_lock
);
224 nsecs
= timekeeping_get_ns();
226 /* If arch requires, add in gettimeoffset() */
227 nsecs
+= arch_gettimeoffset();
229 } while (read_seqretry(&xtime_lock
, seq
));
231 timespec_add_ns(ts
, nsecs
);
234 EXPORT_SYMBOL(getnstimeofday
);
236 ktime_t
ktime_get(void)
241 WARN_ON(timekeeping_suspended
);
244 seq
= read_seqbegin(&xtime_lock
);
245 secs
= xtime
.tv_sec
+ wall_to_monotonic
.tv_sec
;
246 nsecs
= xtime
.tv_nsec
+ wall_to_monotonic
.tv_nsec
;
247 nsecs
+= timekeeping_get_ns();
249 } while (read_seqretry(&xtime_lock
, seq
));
251 * Use ktime_set/ktime_add_ns to create a proper ktime on
252 * 32-bit architectures without CONFIG_KTIME_SCALAR.
254 return ktime_add_ns(ktime_set(secs
, 0), nsecs
);
256 EXPORT_SYMBOL_GPL(ktime_get
);
259 * ktime_get_ts - get the monotonic clock in timespec format
260 * @ts: pointer to timespec variable
262 * The function calculates the monotonic clock from the realtime
263 * clock and the wall_to_monotonic offset and stores the result
264 * in normalized timespec format in the variable pointed to by @ts.
266 void ktime_get_ts(struct timespec
*ts
)
268 struct timespec tomono
;
272 WARN_ON(timekeeping_suspended
);
275 seq
= read_seqbegin(&xtime_lock
);
277 tomono
= wall_to_monotonic
;
278 nsecs
= timekeeping_get_ns();
280 } while (read_seqretry(&xtime_lock
, seq
));
282 set_normalized_timespec(ts
, ts
->tv_sec
+ tomono
.tv_sec
,
283 ts
->tv_nsec
+ tomono
.tv_nsec
+ nsecs
);
285 EXPORT_SYMBOL_GPL(ktime_get_ts
);
288 * do_gettimeofday - Returns the time of day in a timeval
289 * @tv: pointer to the timeval to be set
291 * NOTE: Users should be converted to using getnstimeofday()
293 void do_gettimeofday(struct timeval
*tv
)
297 getnstimeofday(&now
);
298 tv
->tv_sec
= now
.tv_sec
;
299 tv
->tv_usec
= now
.tv_nsec
/1000;
302 EXPORT_SYMBOL(do_gettimeofday
);
304 * do_settimeofday - Sets the time of day
305 * @tv: pointer to the timespec variable containing the new time
307 * Sets the time of day to the new time and update NTP and notify hrtimers
309 int do_settimeofday(struct timespec
*tv
)
311 struct timespec ts_delta
;
314 if ((unsigned long)tv
->tv_nsec
>= NSEC_PER_SEC
)
317 write_seqlock_irqsave(&xtime_lock
, flags
);
319 timekeeping_forward_now();
321 ts_delta
.tv_sec
= tv
->tv_sec
- xtime
.tv_sec
;
322 ts_delta
.tv_nsec
= tv
->tv_nsec
- xtime
.tv_nsec
;
323 wall_to_monotonic
= timespec_sub(wall_to_monotonic
, ts_delta
);
327 timekeeper
.ntp_error
= 0;
330 update_vsyscall(&xtime
, &wall_to_monotonic
, timekeeper
.clock
,
333 write_sequnlock_irqrestore(&xtime_lock
, flags
);
335 /* signal hrtimers about time change */
341 EXPORT_SYMBOL(do_settimeofday
);
344 * change_clocksource - Swaps clocksources if a new one is available
346 * Accumulates current time interval and initializes new clocksource
348 static int change_clocksource(void *data
)
350 struct clocksource
*new, *old
;
352 new = (struct clocksource
*) data
;
354 timekeeping_forward_now();
355 if (!new->enable
|| new->enable(new) == 0) {
356 old
= timekeeper
.clock
;
357 timekeeper_setup_internals(new);
365 * timekeeping_notify - Install a new clock source
366 * @clock: pointer to the clock source
368 * This function is called from clocksource.c after a new, better clock
369 * source has been registered. The caller holds the clocksource_mutex.
371 void timekeeping_notify(struct clocksource
*clock
)
373 if (timekeeper
.clock
== clock
)
375 stop_machine(change_clocksource
, clock
, NULL
);
380 * ktime_get_real - get the real (wall-) time in ktime_t format
382 * returns the time in ktime_t format
384 ktime_t
ktime_get_real(void)
388 getnstimeofday(&now
);
390 return timespec_to_ktime(now
);
392 EXPORT_SYMBOL_GPL(ktime_get_real
);
395 * getrawmonotonic - Returns the raw monotonic time in a timespec
396 * @ts: pointer to the timespec to be set
398 * Returns the raw monotonic time (completely un-modified by ntp)
400 void getrawmonotonic(struct timespec
*ts
)
406 seq
= read_seqbegin(&xtime_lock
);
407 nsecs
= timekeeping_get_ns_raw();
410 } while (read_seqretry(&xtime_lock
, seq
));
412 timespec_add_ns(ts
, nsecs
);
414 EXPORT_SYMBOL(getrawmonotonic
);
418 * timekeeping_valid_for_hres - Check if timekeeping is suitable for hres
420 int timekeeping_valid_for_hres(void)
426 seq
= read_seqbegin(&xtime_lock
);
428 ret
= timekeeper
.clock
->flags
& CLOCK_SOURCE_VALID_FOR_HRES
;
430 } while (read_seqretry(&xtime_lock
, seq
));
436 * timekeeping_max_deferment - Returns max time the clocksource can be deferred
438 * Caller must observe xtime_lock via read_seqbegin/read_seqretry to
439 * ensure that the clocksource does not change!
441 u64
timekeeping_max_deferment(void)
443 return timekeeper
.clock
->max_idle_ns
;
446 void __attribute__((weak
)) read_persistent_clock(struct timespec
*ts
)
452 void __attribute__((weak
)) read_boot_clock(struct timespec
*ts
)
459 * timekeeping_init - Initializes the clocksource and common timekeeping values
461 void __init
timekeeping_init(void)
463 struct clocksource
*clock
;
465 struct timespec now
, boot
;
467 read_persistent_clock(&now
);
468 read_boot_clock(&boot
);
470 write_seqlock_irqsave(&xtime_lock
, flags
);
474 clock
= clocksource_default_clock();
476 clock
->enable(clock
);
477 timekeeper_setup_internals(clock
);
479 xtime
.tv_sec
= now
.tv_sec
;
480 xtime
.tv_nsec
= now
.tv_nsec
;
482 raw_time
.tv_nsec
= 0;
483 if (boot
.tv_sec
== 0 && boot
.tv_nsec
== 0) {
484 boot
.tv_sec
= xtime
.tv_sec
;
485 boot
.tv_nsec
= xtime
.tv_nsec
;
487 set_normalized_timespec(&wall_to_monotonic
,
488 -boot
.tv_sec
, -boot
.tv_nsec
);
489 total_sleep_time
.tv_sec
= 0;
490 total_sleep_time
.tv_nsec
= 0;
491 write_sequnlock_irqrestore(&xtime_lock
, flags
);
494 /* time in seconds when suspend began */
495 static struct timespec timekeeping_suspend_time
;
498 * timekeeping_resume - Resumes the generic timekeeping subsystem.
501 * This is for the generic clocksource timekeeping.
502 * xtime/wall_to_monotonic/jiffies/etc are
503 * still managed by arch specific suspend/resume code.
505 static int timekeeping_resume(struct sys_device
*dev
)
510 read_persistent_clock(&ts
);
512 clocksource_resume();
514 write_seqlock_irqsave(&xtime_lock
, flags
);
516 if (timespec_compare(&ts
, &timekeeping_suspend_time
) > 0) {
517 ts
= timespec_sub(ts
, timekeeping_suspend_time
);
518 xtime
= timespec_add(xtime
, ts
);
519 wall_to_monotonic
= timespec_sub(wall_to_monotonic
, ts
);
520 total_sleep_time
= timespec_add(total_sleep_time
, ts
);
522 /* re-base the last cycle value */
523 timekeeper
.clock
->cycle_last
= timekeeper
.clock
->read(timekeeper
.clock
);
524 timekeeper
.ntp_error
= 0;
525 timekeeping_suspended
= 0;
526 write_sequnlock_irqrestore(&xtime_lock
, flags
);
528 touch_softlockup_watchdog();
530 clockevents_notify(CLOCK_EVT_NOTIFY_RESUME
, NULL
);
532 /* Resume hrtimers */
533 hres_timers_resume();
538 static int timekeeping_suspend(struct sys_device
*dev
, pm_message_t state
)
542 read_persistent_clock(&timekeeping_suspend_time
);
544 write_seqlock_irqsave(&xtime_lock
, flags
);
545 timekeeping_forward_now();
546 timekeeping_suspended
= 1;
547 write_sequnlock_irqrestore(&xtime_lock
, flags
);
549 clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND
, NULL
);
550 clocksource_suspend();
555 /* sysfs resume/suspend bits for timekeeping */
556 static struct sysdev_class timekeeping_sysclass
= {
557 .name
= "timekeeping",
558 .resume
= timekeeping_resume
,
559 .suspend
= timekeeping_suspend
,
562 static struct sys_device device_timer
= {
564 .cls
= &timekeeping_sysclass
,
567 static int __init
timekeeping_init_device(void)
569 int error
= sysdev_class_register(&timekeeping_sysclass
);
571 error
= sysdev_register(&device_timer
);
575 device_initcall(timekeeping_init_device
);
578 * If the error is already larger, we look ahead even further
579 * to compensate for late or lost adjustments.
581 static __always_inline
int timekeeping_bigadjust(s64 error
, s64
*interval
,
589 * Use the current error value to determine how much to look ahead.
590 * The larger the error the slower we adjust for it to avoid problems
591 * with losing too many ticks, otherwise we would overadjust and
592 * produce an even larger error. The smaller the adjustment the
593 * faster we try to adjust for it, as lost ticks can do less harm
594 * here. This is tuned so that an error of about 1 msec is adjusted
595 * within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks).
597 error2
= timekeeper
.ntp_error
>> (NTP_SCALE_SHIFT
+ 22 - 2 * SHIFT_HZ
);
598 error2
= abs(error2
);
599 for (look_ahead
= 0; error2
> 0; look_ahead
++)
603 * Now calculate the error in (1 << look_ahead) ticks, but first
604 * remove the single look ahead already included in the error.
606 tick_error
= tick_length
>> (timekeeper
.ntp_error_shift
+ 1);
607 tick_error
-= timekeeper
.xtime_interval
>> 1;
608 error
= ((error
- tick_error
) >> look_ahead
) + tick_error
;
610 /* Finally calculate the adjustment shift value. */
615 *interval
= -*interval
;
619 for (adj
= 0; error
> i
; adj
++)
628 * Adjust the multiplier to reduce the error value,
629 * this is optimized for the most common adjustments of -1,0,1,
630 * for other values we can do a bit more work.
632 static void timekeeping_adjust(s64 offset
)
634 s64 error
, interval
= timekeeper
.cycle_interval
;
637 error
= timekeeper
.ntp_error
>> (timekeeper
.ntp_error_shift
- 1);
638 if (error
> interval
) {
640 if (likely(error
<= interval
))
643 adj
= timekeeping_bigadjust(error
, &interval
, &offset
);
644 } else if (error
< -interval
) {
646 if (likely(error
>= -interval
)) {
648 interval
= -interval
;
651 adj
= timekeeping_bigadjust(error
, &interval
, &offset
);
655 timekeeper
.mult
+= adj
;
656 timekeeper
.xtime_interval
+= interval
;
657 timekeeper
.xtime_nsec
-= offset
;
658 timekeeper
.ntp_error
-= (interval
- offset
) <<
659 timekeeper
.ntp_error_shift
;
664 * logarithmic_accumulation - shifted accumulation of cycles
666 * This functions accumulates a shifted interval of cycles into
667 * into a shifted interval nanoseconds. Allows for O(log) accumulation
670 * Returns the unconsumed cycles.
672 static cycle_t
logarithmic_accumulation(cycle_t offset
, int shift
)
674 u64 nsecps
= (u64
)NSEC_PER_SEC
<< timekeeper
.shift
;
677 /* If the offset is smaller then a shifted interval, do nothing */
678 if (offset
< timekeeper
.cycle_interval
<<shift
)
681 /* Accumulate one shifted interval */
682 offset
-= timekeeper
.cycle_interval
<< shift
;
683 timekeeper
.clock
->cycle_last
+= timekeeper
.cycle_interval
<< shift
;
685 timekeeper
.xtime_nsec
+= timekeeper
.xtime_interval
<< shift
;
686 while (timekeeper
.xtime_nsec
>= nsecps
) {
687 timekeeper
.xtime_nsec
-= nsecps
;
692 /* Accumulate raw time */
693 raw_nsecs
= timekeeper
.raw_interval
<< shift
;
694 raw_nsecs
+= raw_time
.tv_nsec
;
695 if (raw_nsecs
>= NSEC_PER_SEC
) {
696 u64 raw_secs
= raw_nsecs
;
697 raw_nsecs
= do_div(raw_secs
, NSEC_PER_SEC
);
698 raw_time
.tv_sec
+= raw_secs
;
700 raw_time
.tv_nsec
= raw_nsecs
;
702 /* Accumulate error between NTP and clock interval */
703 timekeeper
.ntp_error
+= tick_length
<< shift
;
704 timekeeper
.ntp_error
-= timekeeper
.xtime_interval
<<
705 (timekeeper
.ntp_error_shift
+ shift
);
712 * update_wall_time - Uses the current clocksource to increment the wall time
714 * Called from the timer interrupt, must hold a write on xtime_lock.
716 void update_wall_time(void)
718 struct clocksource
*clock
;
720 int shift
= 0, maxshift
;
722 /* Make sure we're fully resumed: */
723 if (unlikely(timekeeping_suspended
))
726 clock
= timekeeper
.clock
;
728 #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
729 offset
= timekeeper
.cycle_interval
;
731 offset
= (clock
->read(clock
) - clock
->cycle_last
) & clock
->mask
;
733 timekeeper
.xtime_nsec
= (s64
)xtime
.tv_nsec
<< timekeeper
.shift
;
736 * With NO_HZ we may have to accumulate many cycle_intervals
737 * (think "ticks") worth of time at once. To do this efficiently,
738 * we calculate the largest doubling multiple of cycle_intervals
739 * that is smaller then the offset. We then accumulate that
740 * chunk in one go, and then try to consume the next smaller
743 shift
= ilog2(offset
) - ilog2(timekeeper
.cycle_interval
);
744 shift
= max(0, shift
);
745 /* Bound shift to one less then what overflows tick_length */
746 maxshift
= (8*sizeof(tick_length
) - (ilog2(tick_length
)+1)) - 1;
747 shift
= min(shift
, maxshift
);
748 while (offset
>= timekeeper
.cycle_interval
) {
749 offset
= logarithmic_accumulation(offset
, shift
);
750 if(offset
< timekeeper
.cycle_interval
<<shift
)
754 /* correct the clock when NTP error is too big */
755 timekeeping_adjust(offset
);
758 * Since in the loop above, we accumulate any amount of time
759 * in xtime_nsec over a second into xtime.tv_sec, its possible for
760 * xtime_nsec to be fairly small after the loop. Further, if we're
761 * slightly speeding the clocksource up in timekeeping_adjust(),
762 * its possible the required corrective factor to xtime_nsec could
763 * cause it to underflow.
765 * Now, we cannot simply roll the accumulated second back, since
766 * the NTP subsystem has been notified via second_overflow. So
767 * instead we push xtime_nsec forward by the amount we underflowed,
768 * and add that amount into the error.
770 * We'll correct this error next time through this function, when
771 * xtime_nsec is not as small.
773 if (unlikely((s64
)timekeeper
.xtime_nsec
< 0)) {
774 s64 neg
= -(s64
)timekeeper
.xtime_nsec
;
775 timekeeper
.xtime_nsec
= 0;
776 timekeeper
.ntp_error
+= neg
<< timekeeper
.ntp_error_shift
;
781 * Store full nanoseconds into xtime after rounding it up and
782 * add the remainder to the error difference.
784 xtime
.tv_nsec
= ((s64
) timekeeper
.xtime_nsec
>> timekeeper
.shift
) + 1;
785 timekeeper
.xtime_nsec
-= (s64
) xtime
.tv_nsec
<< timekeeper
.shift
;
786 timekeeper
.ntp_error
+= timekeeper
.xtime_nsec
<<
787 timekeeper
.ntp_error_shift
;
790 * Finally, make sure that after the rounding
791 * xtime.tv_nsec isn't larger then NSEC_PER_SEC
793 if (unlikely(xtime
.tv_nsec
>= NSEC_PER_SEC
)) {
794 xtime
.tv_nsec
-= NSEC_PER_SEC
;
799 /* check to see if there is a new clocksource to use */
800 update_vsyscall(&xtime
, &wall_to_monotonic
, timekeeper
.clock
,
805 * getboottime - Return the real time of system boot.
806 * @ts: pointer to the timespec to be set
808 * Returns the time of day in a timespec.
810 * This is based on the wall_to_monotonic offset and the total suspend
811 * time. Calls to settimeofday will affect the value returned (which
812 * basically means that however wrong your real time clock is at boot time,
813 * you get the right time here).
815 void getboottime(struct timespec
*ts
)
817 struct timespec boottime
= {
818 .tv_sec
= wall_to_monotonic
.tv_sec
+ total_sleep_time
.tv_sec
,
819 .tv_nsec
= wall_to_monotonic
.tv_nsec
+ total_sleep_time
.tv_nsec
822 set_normalized_timespec(ts
, -boottime
.tv_sec
, -boottime
.tv_nsec
);
824 EXPORT_SYMBOL_GPL(getboottime
);
827 * monotonic_to_bootbased - Convert the monotonic time to boot based.
828 * @ts: pointer to the timespec to be converted
830 void monotonic_to_bootbased(struct timespec
*ts
)
832 *ts
= timespec_add(*ts
, total_sleep_time
);
834 EXPORT_SYMBOL_GPL(monotonic_to_bootbased
);
836 unsigned long get_seconds(void)
840 EXPORT_SYMBOL(get_seconds
);
842 struct timespec
__current_kernel_time(void)
847 struct timespec
__get_wall_to_monotonic(void)
849 return wall_to_monotonic
;
852 struct timespec
current_kernel_time(void)
858 seq
= read_seqbegin(&xtime_lock
);
861 } while (read_seqretry(&xtime_lock
, seq
));
865 EXPORT_SYMBOL(current_kernel_time
);
867 struct timespec
get_monotonic_coarse(void)
869 struct timespec now
, mono
;
873 seq
= read_seqbegin(&xtime_lock
);
876 mono
= wall_to_monotonic
;
877 } while (read_seqretry(&xtime_lock
, seq
));
879 set_normalized_timespec(&now
, now
.tv_sec
+ mono
.tv_sec
,
880 now
.tv_nsec
+ mono
.tv_nsec
);