mm/page_alloc: prevent merging between isolated and other pageblocks
[linux-2.6-block.git] / kernel / time / timekeeping.c
CommitLineData
8524070b 1/*
2 * linux/kernel/time/timekeeping.c
3 *
4 * Kernel timekeeping code and accessor functions
5 *
6 * This code was moved from linux/kernel/timer.c.
7 * Please see that file for copyright and history logs.
8 *
9 */
10
d7b4202e 11#include <linux/timekeeper_internal.h>
8524070b 12#include <linux/module.h>
13#include <linux/interrupt.h>
14#include <linux/percpu.h>
15#include <linux/init.h>
16#include <linux/mm.h>
d43c36dc 17#include <linux/sched.h>
e1a85b2c 18#include <linux/syscore_ops.h>
8524070b 19#include <linux/clocksource.h>
20#include <linux/jiffies.h>
21#include <linux/time.h>
22#include <linux/tick.h>
75c5158f 23#include <linux/stop_machine.h>
e0b306fe 24#include <linux/pvclock_gtod.h>
52f5684c 25#include <linux/compiler.h>
8524070b 26
eb93e4d9 27#include "tick-internal.h"
aa6f9c59 28#include "ntp_internal.h"
5c83545f 29#include "timekeeping_internal.h"
155ec602 30
04397fe9
DV
31#define TK_CLEAR_NTP (1 << 0)
32#define TK_MIRROR (1 << 1)
780427f0 33#define TK_CLOCK_WAS_SET (1 << 2)
04397fe9 34
3fdb14fd
TG
35/*
36 * The most important data for readout fits into a single 64 byte
37 * cache line.
38 */
39static struct {
40 seqcount_t seq;
41 struct timekeeper timekeeper;
42} tk_core ____cacheline_aligned;
43
9a7a71b1 44static DEFINE_RAW_SPINLOCK(timekeeper_lock);
48cdc135 45static struct timekeeper shadow_timekeeper;
155ec602 46
4396e058
TG
47/**
48 * struct tk_fast - NMI safe timekeeper
49 * @seq: Sequence counter for protecting updates. The lowest bit
50 * is the index for the tk_read_base array
51 * @base: tk_read_base array. Access is indexed by the lowest bit of
52 * @seq.
53 *
54 * See @update_fast_timekeeper() below.
55 */
56struct tk_fast {
57 seqcount_t seq;
58 struct tk_read_base base[2];
59};
60
61static struct tk_fast tk_fast_mono ____cacheline_aligned;
f09cb9a1 62static struct tk_fast tk_fast_raw ____cacheline_aligned;
4396e058 63
8fcce546
JS
64/* flag for if timekeeping is suspended */
65int __read_mostly timekeeping_suspended;
66
1e75fa8b
JS
67static inline void tk_normalize_xtime(struct timekeeper *tk)
68{
876e7881
PZ
69 while (tk->tkr_mono.xtime_nsec >= ((u64)NSEC_PER_SEC << tk->tkr_mono.shift)) {
70 tk->tkr_mono.xtime_nsec -= (u64)NSEC_PER_SEC << tk->tkr_mono.shift;
1e75fa8b
JS
71 tk->xtime_sec++;
72 }
73}
74
c905fae4
TG
75static inline struct timespec64 tk_xtime(struct timekeeper *tk)
76{
77 struct timespec64 ts;
78
79 ts.tv_sec = tk->xtime_sec;
876e7881 80 ts.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
c905fae4
TG
81 return ts;
82}
83
7d489d15 84static void tk_set_xtime(struct timekeeper *tk, const struct timespec64 *ts)
1e75fa8b
JS
85{
86 tk->xtime_sec = ts->tv_sec;
876e7881 87 tk->tkr_mono.xtime_nsec = (u64)ts->tv_nsec << tk->tkr_mono.shift;
1e75fa8b
JS
88}
89
7d489d15 90static void tk_xtime_add(struct timekeeper *tk, const struct timespec64 *ts)
1e75fa8b
JS
91{
92 tk->xtime_sec += ts->tv_sec;
876e7881 93 tk->tkr_mono.xtime_nsec += (u64)ts->tv_nsec << tk->tkr_mono.shift;
784ffcbb 94 tk_normalize_xtime(tk);
1e75fa8b 95}
8fcce546 96
7d489d15 97static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec64 wtm)
6d0ef903 98{
7d489d15 99 struct timespec64 tmp;
6d0ef903
JS
100
101 /*
102 * Verify consistency of: offset_real = -wall_to_monotonic
103 * before modifying anything
104 */
7d489d15 105 set_normalized_timespec64(&tmp, -tk->wall_to_monotonic.tv_sec,
6d0ef903 106 -tk->wall_to_monotonic.tv_nsec);
7d489d15 107 WARN_ON_ONCE(tk->offs_real.tv64 != timespec64_to_ktime(tmp).tv64);
6d0ef903 108 tk->wall_to_monotonic = wtm;
7d489d15
JS
109 set_normalized_timespec64(&tmp, -wtm.tv_sec, -wtm.tv_nsec);
110 tk->offs_real = timespec64_to_ktime(tmp);
04005f60 111 tk->offs_tai = ktime_add(tk->offs_real, ktime_set(tk->tai_offset, 0));
6d0ef903
JS
112}
113
47da70d3 114static inline void tk_update_sleep_time(struct timekeeper *tk, ktime_t delta)
6d0ef903 115{
47da70d3 116 tk->offs_boot = ktime_add(tk->offs_boot, delta);
6d0ef903
JS
117}
118
3c17ad19 119#ifdef CONFIG_DEBUG_TIMEKEEPING
4ca22c26 120#define WARNING_FREQ (HZ*300) /* 5 minute rate-limiting */
4ca22c26 121
3c17ad19
JS
122static void timekeeping_check_update(struct timekeeper *tk, cycle_t offset)
123{
124
876e7881
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125 cycle_t max_cycles = tk->tkr_mono.clock->max_cycles;
126 const char *name = tk->tkr_mono.clock->name;
3c17ad19
JS
127
128 if (offset > max_cycles) {
a558cd02 129 printk_deferred("WARNING: timekeeping: Cycle offset (%lld) is larger than allowed by the '%s' clock's max_cycles value (%lld): time overflow danger\n",
3c17ad19 130 offset, name, max_cycles);
a558cd02 131 printk_deferred(" timekeeping: Your kernel is sick, but tries to cope by capping time updates\n");
3c17ad19
JS
132 } else {
133 if (offset > (max_cycles >> 1)) {
fc4fa6e1 134 printk_deferred("INFO: timekeeping: Cycle offset (%lld) is larger than the '%s' clock's 50%% safety margin (%lld)\n",
3c17ad19
JS
135 offset, name, max_cycles >> 1);
136 printk_deferred(" timekeeping: Your kernel is still fine, but is feeling a bit nervous\n");
137 }
138 }
4ca22c26 139
57d05a93
JS
140 if (tk->underflow_seen) {
141 if (jiffies - tk->last_warning > WARNING_FREQ) {
4ca22c26
JS
142 printk_deferred("WARNING: Underflow in clocksource '%s' observed, time update ignored.\n", name);
143 printk_deferred(" Please report this, consider using a different clocksource, if possible.\n");
144 printk_deferred(" Your kernel is probably still fine.\n");
57d05a93 145 tk->last_warning = jiffies;
4ca22c26 146 }
57d05a93 147 tk->underflow_seen = 0;
4ca22c26
JS
148 }
149
57d05a93
JS
150 if (tk->overflow_seen) {
151 if (jiffies - tk->last_warning > WARNING_FREQ) {
4ca22c26
JS
152 printk_deferred("WARNING: Overflow in clocksource '%s' observed, time update capped.\n", name);
153 printk_deferred(" Please report this, consider using a different clocksource, if possible.\n");
154 printk_deferred(" Your kernel is probably still fine.\n");
57d05a93 155 tk->last_warning = jiffies;
4ca22c26 156 }
57d05a93 157 tk->overflow_seen = 0;
4ca22c26 158 }
3c17ad19 159}
a558cd02
JS
160
161static inline cycle_t timekeeping_get_delta(struct tk_read_base *tkr)
162{
57d05a93 163 struct timekeeper *tk = &tk_core.timekeeper;
4ca22c26
JS
164 cycle_t now, last, mask, max, delta;
165 unsigned int seq;
a558cd02 166
4ca22c26
JS
167 /*
168 * Since we're called holding a seqlock, the data may shift
169 * under us while we're doing the calculation. This can cause
170 * false positives, since we'd note a problem but throw the
171 * results away. So nest another seqlock here to atomically
172 * grab the points we are checking with.
173 */
174 do {
175 seq = read_seqcount_begin(&tk_core.seq);
176 now = tkr->read(tkr->clock);
177 last = tkr->cycle_last;
178 mask = tkr->mask;
179 max = tkr->clock->max_cycles;
180 } while (read_seqcount_retry(&tk_core.seq, seq));
a558cd02 181
4ca22c26 182 delta = clocksource_delta(now, last, mask);
a558cd02 183
057b87e3
JS
184 /*
185 * Try to catch underflows by checking if we are seeing small
186 * mask-relative negative values.
187 */
4ca22c26 188 if (unlikely((~delta & mask) < (mask >> 3))) {
57d05a93 189 tk->underflow_seen = 1;
057b87e3 190 delta = 0;
4ca22c26 191 }
057b87e3 192
a558cd02 193 /* Cap delta value to the max_cycles values to avoid mult overflows */
4ca22c26 194 if (unlikely(delta > max)) {
57d05a93 195 tk->overflow_seen = 1;
a558cd02 196 delta = tkr->clock->max_cycles;
4ca22c26 197 }
a558cd02
JS
198
199 return delta;
200}
3c17ad19
JS
201#else
202static inline void timekeeping_check_update(struct timekeeper *tk, cycle_t offset)
203{
204}
a558cd02
JS
205static inline cycle_t timekeeping_get_delta(struct tk_read_base *tkr)
206{
207 cycle_t cycle_now, delta;
208
209 /* read clocksource */
210 cycle_now = tkr->read(tkr->clock);
211
212 /* calculate the delta since the last update_wall_time */
213 delta = clocksource_delta(cycle_now, tkr->cycle_last, tkr->mask);
214
215 return delta;
216}
3c17ad19
JS
217#endif
218
155ec602 219/**
d26e4fe0 220 * tk_setup_internals - Set up internals to use clocksource clock.
155ec602 221 *
d26e4fe0 222 * @tk: The target timekeeper to setup.
155ec602
MS
223 * @clock: Pointer to clocksource.
224 *
225 * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment
226 * pair and interval request.
227 *
228 * Unless you're the timekeeping code, you should not be using this!
229 */
f726a697 230static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock)
155ec602
MS
231{
232 cycle_t interval;
a386b5af 233 u64 tmp, ntpinterval;
1e75fa8b 234 struct clocksource *old_clock;
155ec602 235
2c756feb 236 ++tk->cs_was_changed_seq;
876e7881
PZ
237 old_clock = tk->tkr_mono.clock;
238 tk->tkr_mono.clock = clock;
239 tk->tkr_mono.read = clock->read;
240 tk->tkr_mono.mask = clock->mask;
241 tk->tkr_mono.cycle_last = tk->tkr_mono.read(clock);
155ec602 242
4a4ad80d
PZ
243 tk->tkr_raw.clock = clock;
244 tk->tkr_raw.read = clock->read;
245 tk->tkr_raw.mask = clock->mask;
246 tk->tkr_raw.cycle_last = tk->tkr_mono.cycle_last;
247
155ec602
MS
248 /* Do the ns -> cycle conversion first, using original mult */
249 tmp = NTP_INTERVAL_LENGTH;
250 tmp <<= clock->shift;
a386b5af 251 ntpinterval = tmp;
0a544198
MS
252 tmp += clock->mult/2;
253 do_div(tmp, clock->mult);
155ec602
MS
254 if (tmp == 0)
255 tmp = 1;
256
257 interval = (cycle_t) tmp;
f726a697 258 tk->cycle_interval = interval;
155ec602
MS
259
260 /* Go back from cycles -> shifted ns */
f726a697
JS
261 tk->xtime_interval = (u64) interval * clock->mult;
262 tk->xtime_remainder = ntpinterval - tk->xtime_interval;
263 tk->raw_interval =
0a544198 264 ((u64) interval * clock->mult) >> clock->shift;
155ec602 265
1e75fa8b
JS
266 /* if changing clocks, convert xtime_nsec shift units */
267 if (old_clock) {
268 int shift_change = clock->shift - old_clock->shift;
269 if (shift_change < 0)
876e7881 270 tk->tkr_mono.xtime_nsec >>= -shift_change;
1e75fa8b 271 else
876e7881 272 tk->tkr_mono.xtime_nsec <<= shift_change;
1e75fa8b 273 }
4a4ad80d
PZ
274 tk->tkr_raw.xtime_nsec = 0;
275
876e7881 276 tk->tkr_mono.shift = clock->shift;
4a4ad80d 277 tk->tkr_raw.shift = clock->shift;
155ec602 278
f726a697
JS
279 tk->ntp_error = 0;
280 tk->ntp_error_shift = NTP_SCALE_SHIFT - clock->shift;
375f45b5 281 tk->ntp_tick = ntpinterval << tk->ntp_error_shift;
0a544198
MS
282
283 /*
284 * The timekeeper keeps its own mult values for the currently
285 * active clocksource. These value will be adjusted via NTP
286 * to counteract clock drifting.
287 */
876e7881 288 tk->tkr_mono.mult = clock->mult;
4a4ad80d 289 tk->tkr_raw.mult = clock->mult;
dc491596 290 tk->ntp_err_mult = 0;
155ec602 291}
8524070b 292
2ba2a305 293/* Timekeeper helper functions. */
7b1f6207
SW
294
295#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
e06fde37
TG
296static u32 default_arch_gettimeoffset(void) { return 0; }
297u32 (*arch_gettimeoffset)(void) = default_arch_gettimeoffset;
7b1f6207 298#else
e06fde37 299static inline u32 arch_gettimeoffset(void) { return 0; }
7b1f6207
SW
300#endif
301
6bd58f09
CH
302static inline s64 timekeeping_delta_to_ns(struct tk_read_base *tkr,
303 cycle_t delta)
304{
305 s64 nsec;
306
307 nsec = delta * tkr->mult + tkr->xtime_nsec;
308 nsec >>= tkr->shift;
309
310 /* If arch requires, add in get_arch_timeoffset() */
311 return nsec + arch_gettimeoffset();
312}
313
0e5ac3a8 314static inline s64 timekeeping_get_ns(struct tk_read_base *tkr)
2ba2a305 315{
a558cd02 316 cycle_t delta;
2ba2a305 317
a558cd02 318 delta = timekeeping_get_delta(tkr);
6bd58f09
CH
319 return timekeeping_delta_to_ns(tkr, delta);
320}
2ba2a305 321
6bd58f09
CH
322static inline s64 timekeeping_cycles_to_ns(struct tk_read_base *tkr,
323 cycle_t cycles)
324{
325 cycle_t delta;
f2a5a085 326
6bd58f09
CH
327 /* calculate the delta since the last update_wall_time */
328 delta = clocksource_delta(cycles, tkr->cycle_last, tkr->mask);
329 return timekeeping_delta_to_ns(tkr, delta);
2ba2a305
MS
330}
331
4396e058
TG
332/**
333 * update_fast_timekeeper - Update the fast and NMI safe monotonic timekeeper.
affe3e85 334 * @tkr: Timekeeping readout base from which we take the update
4396e058
TG
335 *
336 * We want to use this from any context including NMI and tracing /
337 * instrumenting the timekeeping code itself.
338 *
6695b92a 339 * Employ the latch technique; see @raw_write_seqcount_latch.
4396e058
TG
340 *
341 * So if a NMI hits the update of base[0] then it will use base[1]
342 * which is still consistent. In the worst case this can result is a
343 * slightly wrong timestamp (a few nanoseconds). See
344 * @ktime_get_mono_fast_ns.
345 */
4498e746 346static void update_fast_timekeeper(struct tk_read_base *tkr, struct tk_fast *tkf)
4396e058 347{
4498e746 348 struct tk_read_base *base = tkf->base;
4396e058
TG
349
350 /* Force readers off to base[1] */
4498e746 351 raw_write_seqcount_latch(&tkf->seq);
4396e058
TG
352
353 /* Update base[0] */
affe3e85 354 memcpy(base, tkr, sizeof(*base));
4396e058
TG
355
356 /* Force readers back to base[0] */
4498e746 357 raw_write_seqcount_latch(&tkf->seq);
4396e058
TG
358
359 /* Update base[1] */
360 memcpy(base + 1, base, sizeof(*base));
361}
362
363/**
364 * ktime_get_mono_fast_ns - Fast NMI safe access to clock monotonic
365 *
366 * This timestamp is not guaranteed to be monotonic across an update.
367 * The timestamp is calculated by:
368 *
369 * now = base_mono + clock_delta * slope
370 *
371 * So if the update lowers the slope, readers who are forced to the
372 * not yet updated second array are still using the old steeper slope.
373 *
374 * tmono
375 * ^
376 * | o n
377 * | o n
378 * | u
379 * | o
380 * |o
381 * |12345678---> reader order
382 *
383 * o = old slope
384 * u = update
385 * n = new slope
386 *
387 * So reader 6 will observe time going backwards versus reader 5.
388 *
389 * While other CPUs are likely to be able observe that, the only way
390 * for a CPU local observation is when an NMI hits in the middle of
391 * the update. Timestamps taken from that NMI context might be ahead
392 * of the following timestamps. Callers need to be aware of that and
393 * deal with it.
394 */
4498e746 395static __always_inline u64 __ktime_get_fast_ns(struct tk_fast *tkf)
4396e058
TG
396{
397 struct tk_read_base *tkr;
398 unsigned int seq;
399 u64 now;
400
401 do {
7fc26327 402 seq = raw_read_seqcount_latch(&tkf->seq);
4498e746 403 tkr = tkf->base + (seq & 0x01);
876e7881 404 now = ktime_to_ns(tkr->base) + timekeeping_get_ns(tkr);
4498e746 405 } while (read_seqcount_retry(&tkf->seq, seq));
4396e058 406
4396e058
TG
407 return now;
408}
4498e746
PZ
409
410u64 ktime_get_mono_fast_ns(void)
411{
412 return __ktime_get_fast_ns(&tk_fast_mono);
413}
4396e058
TG
414EXPORT_SYMBOL_GPL(ktime_get_mono_fast_ns);
415
f09cb9a1
PZ
416u64 ktime_get_raw_fast_ns(void)
417{
418 return __ktime_get_fast_ns(&tk_fast_raw);
419}
420EXPORT_SYMBOL_GPL(ktime_get_raw_fast_ns);
421
060407ae
RW
422/* Suspend-time cycles value for halted fast timekeeper. */
423static cycle_t cycles_at_suspend;
424
425static cycle_t dummy_clock_read(struct clocksource *cs)
426{
427 return cycles_at_suspend;
428}
429
430/**
431 * halt_fast_timekeeper - Prevent fast timekeeper from accessing clocksource.
432 * @tk: Timekeeper to snapshot.
433 *
434 * It generally is unsafe to access the clocksource after timekeeping has been
435 * suspended, so take a snapshot of the readout base of @tk and use it as the
436 * fast timekeeper's readout base while suspended. It will return the same
437 * number of cycles every time until timekeeping is resumed at which time the
438 * proper readout base for the fast timekeeper will be restored automatically.
439 */
440static void halt_fast_timekeeper(struct timekeeper *tk)
441{
442 static struct tk_read_base tkr_dummy;
876e7881 443 struct tk_read_base *tkr = &tk->tkr_mono;
060407ae
RW
444
445 memcpy(&tkr_dummy, tkr, sizeof(tkr_dummy));
446 cycles_at_suspend = tkr->read(tkr->clock);
447 tkr_dummy.read = dummy_clock_read;
4498e746 448 update_fast_timekeeper(&tkr_dummy, &tk_fast_mono);
f09cb9a1
PZ
449
450 tkr = &tk->tkr_raw;
451 memcpy(&tkr_dummy, tkr, sizeof(tkr_dummy));
452 tkr_dummy.read = dummy_clock_read;
453 update_fast_timekeeper(&tkr_dummy, &tk_fast_raw);
060407ae
RW
454}
455
c905fae4
TG
456#ifdef CONFIG_GENERIC_TIME_VSYSCALL_OLD
457
458static inline void update_vsyscall(struct timekeeper *tk)
459{
0680eb1f 460 struct timespec xt, wm;
c905fae4 461
e2dff1ec 462 xt = timespec64_to_timespec(tk_xtime(tk));
0680eb1f 463 wm = timespec64_to_timespec(tk->wall_to_monotonic);
876e7881
PZ
464 update_vsyscall_old(&xt, &wm, tk->tkr_mono.clock, tk->tkr_mono.mult,
465 tk->tkr_mono.cycle_last);
c905fae4
TG
466}
467
468static inline void old_vsyscall_fixup(struct timekeeper *tk)
469{
470 s64 remainder;
471
472 /*
473 * Store only full nanoseconds into xtime_nsec after rounding
474 * it up and add the remainder to the error difference.
475 * XXX - This is necessary to avoid small 1ns inconsistnecies caused
476 * by truncating the remainder in vsyscalls. However, it causes
477 * additional work to be done in timekeeping_adjust(). Once
478 * the vsyscall implementations are converted to use xtime_nsec
479 * (shifted nanoseconds), and CONFIG_GENERIC_TIME_VSYSCALL_OLD
480 * users are removed, this can be killed.
481 */
876e7881
PZ
482 remainder = tk->tkr_mono.xtime_nsec & ((1ULL << tk->tkr_mono.shift) - 1);
483 tk->tkr_mono.xtime_nsec -= remainder;
484 tk->tkr_mono.xtime_nsec += 1ULL << tk->tkr_mono.shift;
c905fae4 485 tk->ntp_error += remainder << tk->ntp_error_shift;
876e7881 486 tk->ntp_error -= (1ULL << tk->tkr_mono.shift) << tk->ntp_error_shift;
c905fae4
TG
487}
488#else
489#define old_vsyscall_fixup(tk)
490#endif
491
e0b306fe
MT
492static RAW_NOTIFIER_HEAD(pvclock_gtod_chain);
493
780427f0 494static void update_pvclock_gtod(struct timekeeper *tk, bool was_set)
e0b306fe 495{
780427f0 496 raw_notifier_call_chain(&pvclock_gtod_chain, was_set, tk);
e0b306fe
MT
497}
498
499/**
500 * pvclock_gtod_register_notifier - register a pvclock timedata update listener
e0b306fe
MT
501 */
502int pvclock_gtod_register_notifier(struct notifier_block *nb)
503{
3fdb14fd 504 struct timekeeper *tk = &tk_core.timekeeper;
e0b306fe
MT
505 unsigned long flags;
506 int ret;
507
9a7a71b1 508 raw_spin_lock_irqsave(&timekeeper_lock, flags);
e0b306fe 509 ret = raw_notifier_chain_register(&pvclock_gtod_chain, nb);
780427f0 510 update_pvclock_gtod(tk, true);
9a7a71b1 511 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
e0b306fe
MT
512
513 return ret;
514}
515EXPORT_SYMBOL_GPL(pvclock_gtod_register_notifier);
516
517/**
518 * pvclock_gtod_unregister_notifier - unregister a pvclock
519 * timedata update listener
e0b306fe
MT
520 */
521int pvclock_gtod_unregister_notifier(struct notifier_block *nb)
522{
e0b306fe
MT
523 unsigned long flags;
524 int ret;
525
9a7a71b1 526 raw_spin_lock_irqsave(&timekeeper_lock, flags);
e0b306fe 527 ret = raw_notifier_chain_unregister(&pvclock_gtod_chain, nb);
9a7a71b1 528 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
e0b306fe
MT
529
530 return ret;
531}
532EXPORT_SYMBOL_GPL(pvclock_gtod_unregister_notifier);
533
833f32d7
JS
534/*
535 * tk_update_leap_state - helper to update the next_leap_ktime
536 */
537static inline void tk_update_leap_state(struct timekeeper *tk)
538{
539 tk->next_leap_ktime = ntp_get_next_leap();
540 if (tk->next_leap_ktime.tv64 != KTIME_MAX)
541 /* Convert to monotonic time */
542 tk->next_leap_ktime = ktime_sub(tk->next_leap_ktime, tk->offs_real);
543}
544
7c032df5
TG
545/*
546 * Update the ktime_t based scalar nsec members of the timekeeper
547 */
548static inline void tk_update_ktime_data(struct timekeeper *tk)
549{
9e3680b1
HS
550 u64 seconds;
551 u32 nsec;
7c032df5
TG
552
553 /*
554 * The xtime based monotonic readout is:
555 * nsec = (xtime_sec + wtm_sec) * 1e9 + wtm_nsec + now();
556 * The ktime based monotonic readout is:
557 * nsec = base_mono + now();
558 * ==> base_mono = (xtime_sec + wtm_sec) * 1e9 + wtm_nsec
559 */
9e3680b1
HS
560 seconds = (u64)(tk->xtime_sec + tk->wall_to_monotonic.tv_sec);
561 nsec = (u32) tk->wall_to_monotonic.tv_nsec;
876e7881 562 tk->tkr_mono.base = ns_to_ktime(seconds * NSEC_PER_SEC + nsec);
f519b1a2
TG
563
564 /* Update the monotonic raw base */
4a4ad80d 565 tk->tkr_raw.base = timespec64_to_ktime(tk->raw_time);
9e3680b1
HS
566
567 /*
568 * The sum of the nanoseconds portions of xtime and
569 * wall_to_monotonic can be greater/equal one second. Take
570 * this into account before updating tk->ktime_sec.
571 */
876e7881 572 nsec += (u32)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
9e3680b1
HS
573 if (nsec >= NSEC_PER_SEC)
574 seconds++;
575 tk->ktime_sec = seconds;
7c032df5
TG
576}
577
9a7a71b1 578/* must hold timekeeper_lock */
04397fe9 579static void timekeeping_update(struct timekeeper *tk, unsigned int action)
cc06268c 580{
04397fe9 581 if (action & TK_CLEAR_NTP) {
f726a697 582 tk->ntp_error = 0;
cc06268c
TG
583 ntp_clear();
584 }
48cdc135 585
833f32d7 586 tk_update_leap_state(tk);
7c032df5
TG
587 tk_update_ktime_data(tk);
588
9bf2419f
TG
589 update_vsyscall(tk);
590 update_pvclock_gtod(tk, action & TK_CLOCK_WAS_SET);
591
4498e746 592 update_fast_timekeeper(&tk->tkr_mono, &tk_fast_mono);
f09cb9a1 593 update_fast_timekeeper(&tk->tkr_raw, &tk_fast_raw);
868a3e91
TG
594
595 if (action & TK_CLOCK_WAS_SET)
596 tk->clock_was_set_seq++;
d1518326
JS
597 /*
598 * The mirroring of the data to the shadow-timekeeper needs
599 * to happen last here to ensure we don't over-write the
600 * timekeeper structure on the next update with stale data
601 */
602 if (action & TK_MIRROR)
603 memcpy(&shadow_timekeeper, &tk_core.timekeeper,
604 sizeof(tk_core.timekeeper));
cc06268c
TG
605}
606
8524070b 607/**
155ec602 608 * timekeeping_forward_now - update clock to the current time
8524070b 609 *
9a055117
RZ
610 * Forward the current clock to update its state since the last call to
611 * update_wall_time(). This is useful before significant clock changes,
612 * as it avoids having to deal with this time offset explicitly.
8524070b 613 */
f726a697 614static void timekeeping_forward_now(struct timekeeper *tk)
8524070b 615{
876e7881 616 struct clocksource *clock = tk->tkr_mono.clock;
3a978377 617 cycle_t cycle_now, delta;
9a055117 618 s64 nsec;
8524070b 619
876e7881
PZ
620 cycle_now = tk->tkr_mono.read(clock);
621 delta = clocksource_delta(cycle_now, tk->tkr_mono.cycle_last, tk->tkr_mono.mask);
622 tk->tkr_mono.cycle_last = cycle_now;
4a4ad80d 623 tk->tkr_raw.cycle_last = cycle_now;
8524070b 624
876e7881 625 tk->tkr_mono.xtime_nsec += delta * tk->tkr_mono.mult;
7d27558c 626
7b1f6207 627 /* If arch requires, add in get_arch_timeoffset() */
876e7881 628 tk->tkr_mono.xtime_nsec += (u64)arch_gettimeoffset() << tk->tkr_mono.shift;
7d27558c 629
f726a697 630 tk_normalize_xtime(tk);
2d42244a 631
4a4ad80d 632 nsec = clocksource_cyc2ns(delta, tk->tkr_raw.mult, tk->tkr_raw.shift);
7d489d15 633 timespec64_add_ns(&tk->raw_time, nsec);
8524070b 634}
635
636/**
d6d29896 637 * __getnstimeofday64 - Returns the time of day in a timespec64.
8524070b 638 * @ts: pointer to the timespec to be set
639 *
1e817fb6
KC
640 * Updates the time of day in the timespec.
641 * Returns 0 on success, or -ve when suspended (timespec will be undefined).
8524070b 642 */
d6d29896 643int __getnstimeofday64(struct timespec64 *ts)
8524070b 644{
3fdb14fd 645 struct timekeeper *tk = &tk_core.timekeeper;
8524070b 646 unsigned long seq;
1e75fa8b 647 s64 nsecs = 0;
8524070b 648
649 do {
3fdb14fd 650 seq = read_seqcount_begin(&tk_core.seq);
8524070b 651
4e250fdd 652 ts->tv_sec = tk->xtime_sec;
876e7881 653 nsecs = timekeeping_get_ns(&tk->tkr_mono);
8524070b 654
3fdb14fd 655 } while (read_seqcount_retry(&tk_core.seq, seq));
8524070b 656
ec145bab 657 ts->tv_nsec = 0;
d6d29896 658 timespec64_add_ns(ts, nsecs);
1e817fb6
KC
659
660 /*
661 * Do not bail out early, in case there were callers still using
662 * the value, even in the face of the WARN_ON.
663 */
664 if (unlikely(timekeeping_suspended))
665 return -EAGAIN;
666 return 0;
667}
d6d29896 668EXPORT_SYMBOL(__getnstimeofday64);
1e817fb6
KC
669
670/**
d6d29896 671 * getnstimeofday64 - Returns the time of day in a timespec64.
5322e4c2 672 * @ts: pointer to the timespec64 to be set
1e817fb6 673 *
5322e4c2 674 * Returns the time of day in a timespec64 (WARN if suspended).
1e817fb6 675 */
d6d29896 676void getnstimeofday64(struct timespec64 *ts)
1e817fb6 677{
d6d29896 678 WARN_ON(__getnstimeofday64(ts));
8524070b 679}
d6d29896 680EXPORT_SYMBOL(getnstimeofday64);
8524070b 681
951ed4d3
MS
682ktime_t ktime_get(void)
683{
3fdb14fd 684 struct timekeeper *tk = &tk_core.timekeeper;
951ed4d3 685 unsigned int seq;
a016a5bd
TG
686 ktime_t base;
687 s64 nsecs;
951ed4d3
MS
688
689 WARN_ON(timekeeping_suspended);
690
691 do {
3fdb14fd 692 seq = read_seqcount_begin(&tk_core.seq);
876e7881
PZ
693 base = tk->tkr_mono.base;
694 nsecs = timekeeping_get_ns(&tk->tkr_mono);
951ed4d3 695
3fdb14fd 696 } while (read_seqcount_retry(&tk_core.seq, seq));
24e4a8c3 697
a016a5bd 698 return ktime_add_ns(base, nsecs);
951ed4d3
MS
699}
700EXPORT_SYMBOL_GPL(ktime_get);
701
6374f912
HG
702u32 ktime_get_resolution_ns(void)
703{
704 struct timekeeper *tk = &tk_core.timekeeper;
705 unsigned int seq;
706 u32 nsecs;
707
708 WARN_ON(timekeeping_suspended);
709
710 do {
711 seq = read_seqcount_begin(&tk_core.seq);
712 nsecs = tk->tkr_mono.mult >> tk->tkr_mono.shift;
713 } while (read_seqcount_retry(&tk_core.seq, seq));
714
715 return nsecs;
716}
717EXPORT_SYMBOL_GPL(ktime_get_resolution_ns);
718
0077dc60
TG
719static ktime_t *offsets[TK_OFFS_MAX] = {
720 [TK_OFFS_REAL] = &tk_core.timekeeper.offs_real,
721 [TK_OFFS_BOOT] = &tk_core.timekeeper.offs_boot,
722 [TK_OFFS_TAI] = &tk_core.timekeeper.offs_tai,
723};
724
725ktime_t ktime_get_with_offset(enum tk_offsets offs)
726{
727 struct timekeeper *tk = &tk_core.timekeeper;
728 unsigned int seq;
729 ktime_t base, *offset = offsets[offs];
730 s64 nsecs;
731
732 WARN_ON(timekeeping_suspended);
733
734 do {
735 seq = read_seqcount_begin(&tk_core.seq);
876e7881
PZ
736 base = ktime_add(tk->tkr_mono.base, *offset);
737 nsecs = timekeeping_get_ns(&tk->tkr_mono);
0077dc60
TG
738
739 } while (read_seqcount_retry(&tk_core.seq, seq));
740
741 return ktime_add_ns(base, nsecs);
742
743}
744EXPORT_SYMBOL_GPL(ktime_get_with_offset);
745
9a6b5197
TG
746/**
747 * ktime_mono_to_any() - convert mononotic time to any other time
748 * @tmono: time to convert.
749 * @offs: which offset to use
750 */
751ktime_t ktime_mono_to_any(ktime_t tmono, enum tk_offsets offs)
752{
753 ktime_t *offset = offsets[offs];
754 unsigned long seq;
755 ktime_t tconv;
756
757 do {
758 seq = read_seqcount_begin(&tk_core.seq);
759 tconv = ktime_add(tmono, *offset);
760 } while (read_seqcount_retry(&tk_core.seq, seq));
761
762 return tconv;
763}
764EXPORT_SYMBOL_GPL(ktime_mono_to_any);
765
f519b1a2
TG
766/**
767 * ktime_get_raw - Returns the raw monotonic time in ktime_t format
768 */
769ktime_t ktime_get_raw(void)
770{
771 struct timekeeper *tk = &tk_core.timekeeper;
772 unsigned int seq;
773 ktime_t base;
774 s64 nsecs;
775
776 do {
777 seq = read_seqcount_begin(&tk_core.seq);
4a4ad80d
PZ
778 base = tk->tkr_raw.base;
779 nsecs = timekeeping_get_ns(&tk->tkr_raw);
f519b1a2
TG
780
781 } while (read_seqcount_retry(&tk_core.seq, seq));
782
783 return ktime_add_ns(base, nsecs);
784}
785EXPORT_SYMBOL_GPL(ktime_get_raw);
786
951ed4d3 787/**
d6d29896 788 * ktime_get_ts64 - get the monotonic clock in timespec64 format
951ed4d3
MS
789 * @ts: pointer to timespec variable
790 *
791 * The function calculates the monotonic clock from the realtime
792 * clock and the wall_to_monotonic offset and stores the result
5322e4c2 793 * in normalized timespec64 format in the variable pointed to by @ts.
951ed4d3 794 */
d6d29896 795void ktime_get_ts64(struct timespec64 *ts)
951ed4d3 796{
3fdb14fd 797 struct timekeeper *tk = &tk_core.timekeeper;
d6d29896 798 struct timespec64 tomono;
ec145bab 799 s64 nsec;
951ed4d3 800 unsigned int seq;
951ed4d3
MS
801
802 WARN_ON(timekeeping_suspended);
803
804 do {
3fdb14fd 805 seq = read_seqcount_begin(&tk_core.seq);
d6d29896 806 ts->tv_sec = tk->xtime_sec;
876e7881 807 nsec = timekeeping_get_ns(&tk->tkr_mono);
4e250fdd 808 tomono = tk->wall_to_monotonic;
951ed4d3 809
3fdb14fd 810 } while (read_seqcount_retry(&tk_core.seq, seq));
951ed4d3 811
d6d29896
TG
812 ts->tv_sec += tomono.tv_sec;
813 ts->tv_nsec = 0;
814 timespec64_add_ns(ts, nsec + tomono.tv_nsec);
951ed4d3 815}
d6d29896 816EXPORT_SYMBOL_GPL(ktime_get_ts64);
951ed4d3 817
9e3680b1
HS
818/**
819 * ktime_get_seconds - Get the seconds portion of CLOCK_MONOTONIC
820 *
821 * Returns the seconds portion of CLOCK_MONOTONIC with a single non
822 * serialized read. tk->ktime_sec is of type 'unsigned long' so this
823 * works on both 32 and 64 bit systems. On 32 bit systems the readout
824 * covers ~136 years of uptime which should be enough to prevent
825 * premature wrap arounds.
826 */
827time64_t ktime_get_seconds(void)
828{
829 struct timekeeper *tk = &tk_core.timekeeper;
830
831 WARN_ON(timekeeping_suspended);
832 return tk->ktime_sec;
833}
834EXPORT_SYMBOL_GPL(ktime_get_seconds);
835
dbe7aa62
HS
836/**
837 * ktime_get_real_seconds - Get the seconds portion of CLOCK_REALTIME
838 *
839 * Returns the wall clock seconds since 1970. This replaces the
840 * get_seconds() interface which is not y2038 safe on 32bit systems.
841 *
842 * For 64bit systems the fast access to tk->xtime_sec is preserved. On
843 * 32bit systems the access must be protected with the sequence
844 * counter to provide "atomic" access to the 64bit tk->xtime_sec
845 * value.
846 */
847time64_t ktime_get_real_seconds(void)
848{
849 struct timekeeper *tk = &tk_core.timekeeper;
850 time64_t seconds;
851 unsigned int seq;
852
853 if (IS_ENABLED(CONFIG_64BIT))
854 return tk->xtime_sec;
855
856 do {
857 seq = read_seqcount_begin(&tk_core.seq);
858 seconds = tk->xtime_sec;
859
860 } while (read_seqcount_retry(&tk_core.seq, seq));
861
862 return seconds;
863}
864EXPORT_SYMBOL_GPL(ktime_get_real_seconds);
865
dee36654
D
866/**
867 * __ktime_get_real_seconds - The same as ktime_get_real_seconds
868 * but without the sequence counter protect. This internal function
869 * is called just when timekeeping lock is already held.
870 */
871time64_t __ktime_get_real_seconds(void)
872{
873 struct timekeeper *tk = &tk_core.timekeeper;
874
875 return tk->xtime_sec;
876}
877
9da0f49c
CH
878/**
879 * ktime_get_snapshot - snapshots the realtime/monotonic raw clocks with counter
880 * @systime_snapshot: pointer to struct receiving the system time snapshot
881 */
882void ktime_get_snapshot(struct system_time_snapshot *systime_snapshot)
883{
884 struct timekeeper *tk = &tk_core.timekeeper;
885 unsigned long seq;
886 ktime_t base_raw;
887 ktime_t base_real;
888 s64 nsec_raw;
889 s64 nsec_real;
890 cycle_t now;
891
ba26621e
CH
892 WARN_ON_ONCE(timekeeping_suspended);
893
9da0f49c
CH
894 do {
895 seq = read_seqcount_begin(&tk_core.seq);
896
897 now = tk->tkr_mono.read(tk->tkr_mono.clock);
2c756feb
CH
898 systime_snapshot->cs_was_changed_seq = tk->cs_was_changed_seq;
899 systime_snapshot->clock_was_set_seq = tk->clock_was_set_seq;
9da0f49c
CH
900 base_real = ktime_add(tk->tkr_mono.base,
901 tk_core.timekeeper.offs_real);
902 base_raw = tk->tkr_raw.base;
903 nsec_real = timekeeping_cycles_to_ns(&tk->tkr_mono, now);
904 nsec_raw = timekeeping_cycles_to_ns(&tk->tkr_raw, now);
905 } while (read_seqcount_retry(&tk_core.seq, seq));
906
907 systime_snapshot->cycles = now;
908 systime_snapshot->real = ktime_add_ns(base_real, nsec_real);
909 systime_snapshot->raw = ktime_add_ns(base_raw, nsec_raw);
910}
911EXPORT_SYMBOL_GPL(ktime_get_snapshot);
dee36654 912
2c756feb
CH
913/* Scale base by mult/div checking for overflow */
914static int scale64_check_overflow(u64 mult, u64 div, u64 *base)
915{
916 u64 tmp, rem;
917
918 tmp = div64_u64_rem(*base, div, &rem);
919
920 if (((int)sizeof(u64)*8 - fls64(mult) < fls64(tmp)) ||
921 ((int)sizeof(u64)*8 - fls64(mult) < fls64(rem)))
922 return -EOVERFLOW;
923 tmp *= mult;
924 rem *= mult;
925
926 do_div(rem, div);
927 *base = tmp + rem;
928 return 0;
929}
930
931/**
932 * adjust_historical_crosststamp - adjust crosstimestamp previous to current interval
933 * @history: Snapshot representing start of history
934 * @partial_history_cycles: Cycle offset into history (fractional part)
935 * @total_history_cycles: Total history length in cycles
936 * @discontinuity: True indicates clock was set on history period
937 * @ts: Cross timestamp that should be adjusted using
938 * partial/total ratio
939 *
940 * Helper function used by get_device_system_crosststamp() to correct the
941 * crosstimestamp corresponding to the start of the current interval to the
942 * system counter value (timestamp point) provided by the driver. The
943 * total_history_* quantities are the total history starting at the provided
944 * reference point and ending at the start of the current interval. The cycle
945 * count between the driver timestamp point and the start of the current
946 * interval is partial_history_cycles.
947 */
948static int adjust_historical_crosststamp(struct system_time_snapshot *history,
949 cycle_t partial_history_cycles,
950 cycle_t total_history_cycles,
951 bool discontinuity,
952 struct system_device_crosststamp *ts)
953{
954 struct timekeeper *tk = &tk_core.timekeeper;
955 u64 corr_raw, corr_real;
956 bool interp_forward;
957 int ret;
958
959 if (total_history_cycles == 0 || partial_history_cycles == 0)
960 return 0;
961
962 /* Interpolate shortest distance from beginning or end of history */
963 interp_forward = partial_history_cycles > total_history_cycles/2 ?
964 true : false;
965 partial_history_cycles = interp_forward ?
966 total_history_cycles - partial_history_cycles :
967 partial_history_cycles;
968
969 /*
970 * Scale the monotonic raw time delta by:
971 * partial_history_cycles / total_history_cycles
972 */
973 corr_raw = (u64)ktime_to_ns(
974 ktime_sub(ts->sys_monoraw, history->raw));
975 ret = scale64_check_overflow(partial_history_cycles,
976 total_history_cycles, &corr_raw);
977 if (ret)
978 return ret;
979
980 /*
981 * If there is a discontinuity in the history, scale monotonic raw
982 * correction by:
983 * mult(real)/mult(raw) yielding the realtime correction
984 * Otherwise, calculate the realtime correction similar to monotonic
985 * raw calculation
986 */
987 if (discontinuity) {
988 corr_real = mul_u64_u32_div
989 (corr_raw, tk->tkr_mono.mult, tk->tkr_raw.mult);
990 } else {
991 corr_real = (u64)ktime_to_ns(
992 ktime_sub(ts->sys_realtime, history->real));
993 ret = scale64_check_overflow(partial_history_cycles,
994 total_history_cycles, &corr_real);
995 if (ret)
996 return ret;
997 }
998
999 /* Fixup monotonic raw and real time time values */
1000 if (interp_forward) {
1001 ts->sys_monoraw = ktime_add_ns(history->raw, corr_raw);
1002 ts->sys_realtime = ktime_add_ns(history->real, corr_real);
1003 } else {
1004 ts->sys_monoraw = ktime_sub_ns(ts->sys_monoraw, corr_raw);
1005 ts->sys_realtime = ktime_sub_ns(ts->sys_realtime, corr_real);
1006 }
1007
1008 return 0;
1009}
1010
1011/*
1012 * cycle_between - true if test occurs chronologically between before and after
1013 */
1014static bool cycle_between(cycle_t before, cycle_t test, cycle_t after)
1015{
1016 if (test > before && test < after)
1017 return true;
1018 if (test < before && before > after)
1019 return true;
1020 return false;
1021}
1022
8006c245
CH
1023/**
1024 * get_device_system_crosststamp - Synchronously capture system/device timestamp
2c756feb 1025 * @get_time_fn: Callback to get simultaneous device time and
8006c245 1026 * system counter from the device driver
2c756feb
CH
1027 * @ctx: Context passed to get_time_fn()
1028 * @history_begin: Historical reference point used to interpolate system
1029 * time when counter provided by the driver is before the current interval
8006c245
CH
1030 * @xtstamp: Receives simultaneously captured system and device time
1031 *
1032 * Reads a timestamp from a device and correlates it to system time
1033 */
1034int get_device_system_crosststamp(int (*get_time_fn)
1035 (ktime_t *device_time,
1036 struct system_counterval_t *sys_counterval,
1037 void *ctx),
1038 void *ctx,
2c756feb 1039 struct system_time_snapshot *history_begin,
8006c245
CH
1040 struct system_device_crosststamp *xtstamp)
1041{
1042 struct system_counterval_t system_counterval;
1043 struct timekeeper *tk = &tk_core.timekeeper;
2c756feb 1044 cycle_t cycles, now, interval_start;
6436257b 1045 unsigned int clock_was_set_seq = 0;
8006c245
CH
1046 ktime_t base_real, base_raw;
1047 s64 nsec_real, nsec_raw;
2c756feb 1048 u8 cs_was_changed_seq;
8006c245 1049 unsigned long seq;
2c756feb 1050 bool do_interp;
8006c245
CH
1051 int ret;
1052
1053 do {
1054 seq = read_seqcount_begin(&tk_core.seq);
1055 /*
1056 * Try to synchronously capture device time and a system
1057 * counter value calling back into the device driver
1058 */
1059 ret = get_time_fn(&xtstamp->device, &system_counterval, ctx);
1060 if (ret)
1061 return ret;
1062
1063 /*
1064 * Verify that the clocksource associated with the captured
1065 * system counter value is the same as the currently installed
1066 * timekeeper clocksource
1067 */
1068 if (tk->tkr_mono.clock != system_counterval.cs)
1069 return -ENODEV;
2c756feb
CH
1070 cycles = system_counterval.cycles;
1071
1072 /*
1073 * Check whether the system counter value provided by the
1074 * device driver is on the current timekeeping interval.
1075 */
1076 now = tk->tkr_mono.read(tk->tkr_mono.clock);
1077 interval_start = tk->tkr_mono.cycle_last;
1078 if (!cycle_between(interval_start, cycles, now)) {
1079 clock_was_set_seq = tk->clock_was_set_seq;
1080 cs_was_changed_seq = tk->cs_was_changed_seq;
1081 cycles = interval_start;
1082 do_interp = true;
1083 } else {
1084 do_interp = false;
1085 }
8006c245
CH
1086
1087 base_real = ktime_add(tk->tkr_mono.base,
1088 tk_core.timekeeper.offs_real);
1089 base_raw = tk->tkr_raw.base;
1090
1091 nsec_real = timekeeping_cycles_to_ns(&tk->tkr_mono,
1092 system_counterval.cycles);
1093 nsec_raw = timekeeping_cycles_to_ns(&tk->tkr_raw,
1094 system_counterval.cycles);
1095 } while (read_seqcount_retry(&tk_core.seq, seq));
1096
1097 xtstamp->sys_realtime = ktime_add_ns(base_real, nsec_real);
1098 xtstamp->sys_monoraw = ktime_add_ns(base_raw, nsec_raw);
2c756feb
CH
1099
1100 /*
1101 * Interpolate if necessary, adjusting back from the start of the
1102 * current interval
1103 */
1104 if (do_interp) {
1105 cycle_t partial_history_cycles, total_history_cycles;
1106 bool discontinuity;
1107
1108 /*
1109 * Check that the counter value occurs after the provided
1110 * history reference and that the history doesn't cross a
1111 * clocksource change
1112 */
1113 if (!history_begin ||
1114 !cycle_between(history_begin->cycles,
1115 system_counterval.cycles, cycles) ||
1116 history_begin->cs_was_changed_seq != cs_was_changed_seq)
1117 return -EINVAL;
1118 partial_history_cycles = cycles - system_counterval.cycles;
1119 total_history_cycles = cycles - history_begin->cycles;
1120 discontinuity =
1121 history_begin->clock_was_set_seq != clock_was_set_seq;
1122
1123 ret = adjust_historical_crosststamp(history_begin,
1124 partial_history_cycles,
1125 total_history_cycles,
1126 discontinuity, xtstamp);
1127 if (ret)
1128 return ret;
1129 }
1130
8006c245
CH
1131 return 0;
1132}
1133EXPORT_SYMBOL_GPL(get_device_system_crosststamp);
1134
8524070b 1135/**
1136 * do_gettimeofday - Returns the time of day in a timeval
1137 * @tv: pointer to the timeval to be set
1138 *
efd9ac86 1139 * NOTE: Users should be converted to using getnstimeofday()
8524070b 1140 */
1141void do_gettimeofday(struct timeval *tv)
1142{
d6d29896 1143 struct timespec64 now;
8524070b 1144
d6d29896 1145 getnstimeofday64(&now);
8524070b 1146 tv->tv_sec = now.tv_sec;
1147 tv->tv_usec = now.tv_nsec/1000;
1148}
8524070b 1149EXPORT_SYMBOL(do_gettimeofday);
d239f49d 1150
8524070b 1151/**
21f7eca5 1152 * do_settimeofday64 - Sets the time of day.
1153 * @ts: pointer to the timespec64 variable containing the new time
8524070b 1154 *
1155 * Sets the time of day to the new time and update NTP and notify hrtimers
1156 */
21f7eca5 1157int do_settimeofday64(const struct timespec64 *ts)
8524070b 1158{
3fdb14fd 1159 struct timekeeper *tk = &tk_core.timekeeper;
21f7eca5 1160 struct timespec64 ts_delta, xt;
92c1d3ed 1161 unsigned long flags;
e1d7ba87 1162 int ret = 0;
8524070b 1163
21f7eca5 1164 if (!timespec64_valid_strict(ts))
8524070b 1165 return -EINVAL;
1166
9a7a71b1 1167 raw_spin_lock_irqsave(&timekeeper_lock, flags);
3fdb14fd 1168 write_seqcount_begin(&tk_core.seq);
8524070b 1169
4e250fdd 1170 timekeeping_forward_now(tk);
9a055117 1171
4e250fdd 1172 xt = tk_xtime(tk);
21f7eca5 1173 ts_delta.tv_sec = ts->tv_sec - xt.tv_sec;
1174 ts_delta.tv_nsec = ts->tv_nsec - xt.tv_nsec;
1e75fa8b 1175
e1d7ba87
WY
1176 if (timespec64_compare(&tk->wall_to_monotonic, &ts_delta) > 0) {
1177 ret = -EINVAL;
1178 goto out;
1179 }
1180
7d489d15 1181 tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, ts_delta));
8524070b 1182
21f7eca5 1183 tk_set_xtime(tk, ts);
e1d7ba87 1184out:
780427f0 1185 timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);
8524070b 1186
3fdb14fd 1187 write_seqcount_end(&tk_core.seq);
9a7a71b1 1188 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
8524070b 1189
1190 /* signal hrtimers about time change */
1191 clock_was_set();
1192
e1d7ba87 1193 return ret;
8524070b 1194}
21f7eca5 1195EXPORT_SYMBOL(do_settimeofday64);
8524070b 1196
c528f7c6
JS
1197/**
1198 * timekeeping_inject_offset - Adds or subtracts from the current time.
1199 * @tv: pointer to the timespec variable containing the offset
1200 *
1201 * Adds or subtracts an offset value from the current time.
1202 */
1203int timekeeping_inject_offset(struct timespec *ts)
1204{
3fdb14fd 1205 struct timekeeper *tk = &tk_core.timekeeper;
92c1d3ed 1206 unsigned long flags;
7d489d15 1207 struct timespec64 ts64, tmp;
4e8b1452 1208 int ret = 0;
c528f7c6 1209
37cf4dc3 1210 if (!timespec_inject_offset_valid(ts))
c528f7c6
JS
1211 return -EINVAL;
1212
7d489d15
JS
1213 ts64 = timespec_to_timespec64(*ts);
1214
9a7a71b1 1215 raw_spin_lock_irqsave(&timekeeper_lock, flags);
3fdb14fd 1216 write_seqcount_begin(&tk_core.seq);
c528f7c6 1217
4e250fdd 1218 timekeeping_forward_now(tk);
c528f7c6 1219
4e8b1452 1220 /* Make sure the proposed value is valid */
7d489d15 1221 tmp = timespec64_add(tk_xtime(tk), ts64);
e1d7ba87
WY
1222 if (timespec64_compare(&tk->wall_to_monotonic, &ts64) > 0 ||
1223 !timespec64_valid_strict(&tmp)) {
4e8b1452
JS
1224 ret = -EINVAL;
1225 goto error;
1226 }
1e75fa8b 1227
7d489d15
JS
1228 tk_xtime_add(tk, &ts64);
1229 tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, ts64));
c528f7c6 1230
4e8b1452 1231error: /* even if we error out, we forwarded the time, so call update */
780427f0 1232 timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);
c528f7c6 1233
3fdb14fd 1234 write_seqcount_end(&tk_core.seq);
9a7a71b1 1235 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
c528f7c6
JS
1236
1237 /* signal hrtimers about time change */
1238 clock_was_set();
1239
4e8b1452 1240 return ret;
c528f7c6
JS
1241}
1242EXPORT_SYMBOL(timekeeping_inject_offset);
1243
cc244dda
JS
1244
1245/**
1246 * timekeeping_get_tai_offset - Returns current TAI offset from UTC
1247 *
1248 */
1249s32 timekeeping_get_tai_offset(void)
1250{
3fdb14fd 1251 struct timekeeper *tk = &tk_core.timekeeper;
cc244dda
JS
1252 unsigned int seq;
1253 s32 ret;
1254
1255 do {
3fdb14fd 1256 seq = read_seqcount_begin(&tk_core.seq);
cc244dda 1257 ret = tk->tai_offset;
3fdb14fd 1258 } while (read_seqcount_retry(&tk_core.seq, seq));
cc244dda
JS
1259
1260 return ret;
1261}
1262
1263/**
1264 * __timekeeping_set_tai_offset - Lock free worker function
1265 *
1266 */
dd5d70e8 1267static void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset)
cc244dda
JS
1268{
1269 tk->tai_offset = tai_offset;
04005f60 1270 tk->offs_tai = ktime_add(tk->offs_real, ktime_set(tai_offset, 0));
cc244dda
JS
1271}
1272
1273/**
1274 * timekeeping_set_tai_offset - Sets the current TAI offset from UTC
1275 *
1276 */
1277void timekeeping_set_tai_offset(s32 tai_offset)
1278{
3fdb14fd 1279 struct timekeeper *tk = &tk_core.timekeeper;
cc244dda
JS
1280 unsigned long flags;
1281
9a7a71b1 1282 raw_spin_lock_irqsave(&timekeeper_lock, flags);
3fdb14fd 1283 write_seqcount_begin(&tk_core.seq);
cc244dda 1284 __timekeeping_set_tai_offset(tk, tai_offset);
f55c0760 1285 timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
3fdb14fd 1286 write_seqcount_end(&tk_core.seq);
9a7a71b1 1287 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
4e8f8b34 1288 clock_was_set();
cc244dda
JS
1289}
1290
8524070b 1291/**
1292 * change_clocksource - Swaps clocksources if a new one is available
1293 *
1294 * Accumulates current time interval and initializes new clocksource
1295 */
75c5158f 1296static int change_clocksource(void *data)
8524070b 1297{
3fdb14fd 1298 struct timekeeper *tk = &tk_core.timekeeper;
4614e6ad 1299 struct clocksource *new, *old;
f695cf94 1300 unsigned long flags;
8524070b 1301
75c5158f 1302 new = (struct clocksource *) data;
8524070b 1303
9a7a71b1 1304 raw_spin_lock_irqsave(&timekeeper_lock, flags);
3fdb14fd 1305 write_seqcount_begin(&tk_core.seq);
f695cf94 1306
4e250fdd 1307 timekeeping_forward_now(tk);
09ac369c
TG
1308 /*
1309 * If the cs is in module, get a module reference. Succeeds
1310 * for built-in code (owner == NULL) as well.
1311 */
1312 if (try_module_get(new->owner)) {
1313 if (!new->enable || new->enable(new) == 0) {
876e7881 1314 old = tk->tkr_mono.clock;
09ac369c
TG
1315 tk_setup_internals(tk, new);
1316 if (old->disable)
1317 old->disable(old);
1318 module_put(old->owner);
1319 } else {
1320 module_put(new->owner);
1321 }
75c5158f 1322 }
780427f0 1323 timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);
f695cf94 1324
3fdb14fd 1325 write_seqcount_end(&tk_core.seq);
9a7a71b1 1326 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
f695cf94 1327
75c5158f
MS
1328 return 0;
1329}
8524070b 1330
75c5158f
MS
1331/**
1332 * timekeeping_notify - Install a new clock source
1333 * @clock: pointer to the clock source
1334 *
1335 * This function is called from clocksource.c after a new, better clock
1336 * source has been registered. The caller holds the clocksource_mutex.
1337 */
ba919d1c 1338int timekeeping_notify(struct clocksource *clock)
75c5158f 1339{
3fdb14fd 1340 struct timekeeper *tk = &tk_core.timekeeper;
4e250fdd 1341
876e7881 1342 if (tk->tkr_mono.clock == clock)
ba919d1c 1343 return 0;
75c5158f 1344 stop_machine(change_clocksource, clock, NULL);
8524070b 1345 tick_clock_notify();
876e7881 1346 return tk->tkr_mono.clock == clock ? 0 : -1;
8524070b 1347}
75c5158f 1348
2d42244a 1349/**
cdba2ec5
JS
1350 * getrawmonotonic64 - Returns the raw monotonic time in a timespec
1351 * @ts: pointer to the timespec64 to be set
2d42244a
JS
1352 *
1353 * Returns the raw monotonic time (completely un-modified by ntp)
1354 */
cdba2ec5 1355void getrawmonotonic64(struct timespec64 *ts)
2d42244a 1356{
3fdb14fd 1357 struct timekeeper *tk = &tk_core.timekeeper;
7d489d15 1358 struct timespec64 ts64;
2d42244a
JS
1359 unsigned long seq;
1360 s64 nsecs;
2d42244a
JS
1361
1362 do {
3fdb14fd 1363 seq = read_seqcount_begin(&tk_core.seq);
4a4ad80d 1364 nsecs = timekeeping_get_ns(&tk->tkr_raw);
7d489d15 1365 ts64 = tk->raw_time;
2d42244a 1366
3fdb14fd 1367 } while (read_seqcount_retry(&tk_core.seq, seq));
2d42244a 1368
7d489d15 1369 timespec64_add_ns(&ts64, nsecs);
cdba2ec5 1370 *ts = ts64;
2d42244a 1371}
cdba2ec5
JS
1372EXPORT_SYMBOL(getrawmonotonic64);
1373
2d42244a 1374
8524070b 1375/**
cf4fc6cb 1376 * timekeeping_valid_for_hres - Check if timekeeping is suitable for hres
8524070b 1377 */
cf4fc6cb 1378int timekeeping_valid_for_hres(void)
8524070b 1379{
3fdb14fd 1380 struct timekeeper *tk = &tk_core.timekeeper;
8524070b 1381 unsigned long seq;
1382 int ret;
1383
1384 do {
3fdb14fd 1385 seq = read_seqcount_begin(&tk_core.seq);
8524070b 1386
876e7881 1387 ret = tk->tkr_mono.clock->flags & CLOCK_SOURCE_VALID_FOR_HRES;
8524070b 1388
3fdb14fd 1389 } while (read_seqcount_retry(&tk_core.seq, seq));
8524070b 1390
1391 return ret;
1392}
1393
98962465
JH
1394/**
1395 * timekeeping_max_deferment - Returns max time the clocksource can be deferred
98962465
JH
1396 */
1397u64 timekeeping_max_deferment(void)
1398{
3fdb14fd 1399 struct timekeeper *tk = &tk_core.timekeeper;
70471f2f
JS
1400 unsigned long seq;
1401 u64 ret;
42e71e81 1402
70471f2f 1403 do {
3fdb14fd 1404 seq = read_seqcount_begin(&tk_core.seq);
70471f2f 1405
876e7881 1406 ret = tk->tkr_mono.clock->max_idle_ns;
70471f2f 1407
3fdb14fd 1408 } while (read_seqcount_retry(&tk_core.seq, seq));
70471f2f
JS
1409
1410 return ret;
98962465
JH
1411}
1412
8524070b 1413/**
d4f587c6 1414 * read_persistent_clock - Return time from the persistent clock.
8524070b 1415 *
1416 * Weak dummy function for arches that do not yet support it.
d4f587c6
MS
1417 * Reads the time from the battery backed persistent clock.
1418 * Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported.
8524070b 1419 *
1420 * XXX - Do be sure to remove it once all arches implement it.
1421 */
52f5684c 1422void __weak read_persistent_clock(struct timespec *ts)
8524070b 1423{
d4f587c6
MS
1424 ts->tv_sec = 0;
1425 ts->tv_nsec = 0;
8524070b 1426}
1427
2ee96632
XP
1428void __weak read_persistent_clock64(struct timespec64 *ts64)
1429{
1430 struct timespec ts;
1431
1432 read_persistent_clock(&ts);
1433 *ts64 = timespec_to_timespec64(ts);
1434}
1435
23970e38 1436/**
e83d0a41 1437 * read_boot_clock64 - Return time of the system start.
23970e38
MS
1438 *
1439 * Weak dummy function for arches that do not yet support it.
1440 * Function to read the exact time the system has been started.
e83d0a41 1441 * Returns a timespec64 with tv_sec=0 and tv_nsec=0 if unsupported.
23970e38
MS
1442 *
1443 * XXX - Do be sure to remove it once all arches implement it.
1444 */
e83d0a41 1445void __weak read_boot_clock64(struct timespec64 *ts)
23970e38
MS
1446{
1447 ts->tv_sec = 0;
1448 ts->tv_nsec = 0;
1449}
1450
0fa88cb4
XP
1451/* Flag for if timekeeping_resume() has injected sleeptime */
1452static bool sleeptime_injected;
1453
1454/* Flag for if there is a persistent clock on this platform */
1455static bool persistent_clock_exists;
1456
8524070b 1457/*
1458 * timekeeping_init - Initializes the clocksource and common timekeeping values
1459 */
1460void __init timekeeping_init(void)
1461{
3fdb14fd 1462 struct timekeeper *tk = &tk_core.timekeeper;
155ec602 1463 struct clocksource *clock;
8524070b 1464 unsigned long flags;
7d489d15 1465 struct timespec64 now, boot, tmp;
31ade306 1466
2ee96632 1467 read_persistent_clock64(&now);
7d489d15 1468 if (!timespec64_valid_strict(&now)) {
4e8b1452
JS
1469 pr_warn("WARNING: Persistent clock returned invalid value!\n"
1470 " Check your CMOS/BIOS settings.\n");
1471 now.tv_sec = 0;
1472 now.tv_nsec = 0;
31ade306 1473 } else if (now.tv_sec || now.tv_nsec)
0fa88cb4 1474 persistent_clock_exists = true;
4e8b1452 1475
9a806ddb 1476 read_boot_clock64(&boot);
7d489d15 1477 if (!timespec64_valid_strict(&boot)) {
4e8b1452
JS
1478 pr_warn("WARNING: Boot clock returned invalid value!\n"
1479 " Check your CMOS/BIOS settings.\n");
1480 boot.tv_sec = 0;
1481 boot.tv_nsec = 0;
1482 }
8524070b 1483
9a7a71b1 1484 raw_spin_lock_irqsave(&timekeeper_lock, flags);
3fdb14fd 1485 write_seqcount_begin(&tk_core.seq);
06c017fd
JS
1486 ntp_init();
1487
f1b82746 1488 clock = clocksource_default_clock();
a0f7d48b
MS
1489 if (clock->enable)
1490 clock->enable(clock);
4e250fdd 1491 tk_setup_internals(tk, clock);
8524070b 1492
4e250fdd
JS
1493 tk_set_xtime(tk, &now);
1494 tk->raw_time.tv_sec = 0;
1495 tk->raw_time.tv_nsec = 0;
1e75fa8b 1496 if (boot.tv_sec == 0 && boot.tv_nsec == 0)
4e250fdd 1497 boot = tk_xtime(tk);
1e75fa8b 1498
7d489d15 1499 set_normalized_timespec64(&tmp, -boot.tv_sec, -boot.tv_nsec);
4e250fdd 1500 tk_set_wall_to_mono(tk, tmp);
6d0ef903 1501
56fd16ca 1502 timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
48cdc135 1503
3fdb14fd 1504 write_seqcount_end(&tk_core.seq);
9a7a71b1 1505 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
8524070b 1506}
1507
264bb3f7 1508/* time in seconds when suspend began for persistent clock */
7d489d15 1509static struct timespec64 timekeeping_suspend_time;
8524070b 1510
304529b1
JS
1511/**
1512 * __timekeeping_inject_sleeptime - Internal function to add sleep interval
1513 * @delta: pointer to a timespec delta value
1514 *
1515 * Takes a timespec offset measuring a suspend interval and properly
1516 * adds the sleep offset to the timekeeping variables.
1517 */
f726a697 1518static void __timekeeping_inject_sleeptime(struct timekeeper *tk,
7d489d15 1519 struct timespec64 *delta)
304529b1 1520{
7d489d15 1521 if (!timespec64_valid_strict(delta)) {
6d9bcb62
JS
1522 printk_deferred(KERN_WARNING
1523 "__timekeeping_inject_sleeptime: Invalid "
1524 "sleep delta value!\n");
cb5de2f8
JS
1525 return;
1526 }
f726a697 1527 tk_xtime_add(tk, delta);
7d489d15 1528 tk_set_wall_to_mono(tk, timespec64_sub(tk->wall_to_monotonic, *delta));
47da70d3 1529 tk_update_sleep_time(tk, timespec64_to_ktime(*delta));
5c83545f 1530 tk_debug_account_sleep_time(delta);
304529b1
JS
1531}
1532
7f298139 1533#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_RTC_HCTOSYS_DEVICE)
0fa88cb4
XP
1534/**
1535 * We have three kinds of time sources to use for sleep time
1536 * injection, the preference order is:
1537 * 1) non-stop clocksource
1538 * 2) persistent clock (ie: RTC accessible when irqs are off)
1539 * 3) RTC
1540 *
1541 * 1) and 2) are used by timekeeping, 3) by RTC subsystem.
1542 * If system has neither 1) nor 2), 3) will be used finally.
1543 *
1544 *
1545 * If timekeeping has injected sleeptime via either 1) or 2),
1546 * 3) becomes needless, so in this case we don't need to call
1547 * rtc_resume(), and this is what timekeeping_rtc_skipresume()
1548 * means.
1549 */
1550bool timekeeping_rtc_skipresume(void)
1551{
1552 return sleeptime_injected;
1553}
1554
1555/**
1556 * 1) can be determined whether to use or not only when doing
1557 * timekeeping_resume() which is invoked after rtc_suspend(),
1558 * so we can't skip rtc_suspend() surely if system has 1).
1559 *
1560 * But if system has 2), 2) will definitely be used, so in this
1561 * case we don't need to call rtc_suspend(), and this is what
1562 * timekeeping_rtc_skipsuspend() means.
1563 */
1564bool timekeeping_rtc_skipsuspend(void)
1565{
1566 return persistent_clock_exists;
1567}
1568
304529b1 1569/**
04d90890 1570 * timekeeping_inject_sleeptime64 - Adds suspend interval to timeekeeping values
1571 * @delta: pointer to a timespec64 delta value
304529b1 1572 *
2ee96632 1573 * This hook is for architectures that cannot support read_persistent_clock64
304529b1 1574 * because their RTC/persistent clock is only accessible when irqs are enabled.
0fa88cb4 1575 * and also don't have an effective nonstop clocksource.
304529b1
JS
1576 *
1577 * This function should only be called by rtc_resume(), and allows
1578 * a suspend offset to be injected into the timekeeping values.
1579 */
04d90890 1580void timekeeping_inject_sleeptime64(struct timespec64 *delta)
304529b1 1581{
3fdb14fd 1582 struct timekeeper *tk = &tk_core.timekeeper;
92c1d3ed 1583 unsigned long flags;
304529b1 1584
9a7a71b1 1585 raw_spin_lock_irqsave(&timekeeper_lock, flags);
3fdb14fd 1586 write_seqcount_begin(&tk_core.seq);
70471f2f 1587
4e250fdd 1588 timekeeping_forward_now(tk);
304529b1 1589
04d90890 1590 __timekeeping_inject_sleeptime(tk, delta);
304529b1 1591
780427f0 1592 timekeeping_update(tk, TK_CLEAR_NTP | TK_MIRROR | TK_CLOCK_WAS_SET);
304529b1 1593
3fdb14fd 1594 write_seqcount_end(&tk_core.seq);
9a7a71b1 1595 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
304529b1
JS
1596
1597 /* signal hrtimers about time change */
1598 clock_was_set();
1599}
7f298139 1600#endif
304529b1 1601
8524070b 1602/**
1603 * timekeeping_resume - Resumes the generic timekeeping subsystem.
8524070b 1604 */
124cf911 1605void timekeeping_resume(void)
8524070b 1606{
3fdb14fd 1607 struct timekeeper *tk = &tk_core.timekeeper;
876e7881 1608 struct clocksource *clock = tk->tkr_mono.clock;
92c1d3ed 1609 unsigned long flags;
7d489d15 1610 struct timespec64 ts_new, ts_delta;
e445cf1c 1611 cycle_t cycle_now, cycle_delta;
d4f587c6 1612
0fa88cb4 1613 sleeptime_injected = false;
2ee96632 1614 read_persistent_clock64(&ts_new);
8524070b 1615
adc78e6b 1616 clockevents_resume();
d10ff3fb
TG
1617 clocksource_resume();
1618
9a7a71b1 1619 raw_spin_lock_irqsave(&timekeeper_lock, flags);
3fdb14fd 1620 write_seqcount_begin(&tk_core.seq);
8524070b 1621
e445cf1c
FT
1622 /*
1623 * After system resumes, we need to calculate the suspended time and
1624 * compensate it for the OS time. There are 3 sources that could be
1625 * used: Nonstop clocksource during suspend, persistent clock and rtc
1626 * device.
1627 *
1628 * One specific platform may have 1 or 2 or all of them, and the
1629 * preference will be:
1630 * suspend-nonstop clocksource -> persistent clock -> rtc
1631 * The less preferred source will only be tried if there is no better
1632 * usable source. The rtc part is handled separately in rtc core code.
1633 */
876e7881 1634 cycle_now = tk->tkr_mono.read(clock);
e445cf1c 1635 if ((clock->flags & CLOCK_SOURCE_SUSPEND_NONSTOP) &&
876e7881 1636 cycle_now > tk->tkr_mono.cycle_last) {
e445cf1c
FT
1637 u64 num, max = ULLONG_MAX;
1638 u32 mult = clock->mult;
1639 u32 shift = clock->shift;
1640 s64 nsec = 0;
1641
876e7881
PZ
1642 cycle_delta = clocksource_delta(cycle_now, tk->tkr_mono.cycle_last,
1643 tk->tkr_mono.mask);
e445cf1c
FT
1644
1645 /*
1646 * "cycle_delta * mutl" may cause 64 bits overflow, if the
1647 * suspended time is too long. In that case we need do the
1648 * 64 bits math carefully
1649 */
1650 do_div(max, mult);
1651 if (cycle_delta > max) {
1652 num = div64_u64(cycle_delta, max);
1653 nsec = (((u64) max * mult) >> shift) * num;
1654 cycle_delta -= num * max;
1655 }
1656 nsec += ((u64) cycle_delta * mult) >> shift;
1657
7d489d15 1658 ts_delta = ns_to_timespec64(nsec);
0fa88cb4 1659 sleeptime_injected = true;
7d489d15
JS
1660 } else if (timespec64_compare(&ts_new, &timekeeping_suspend_time) > 0) {
1661 ts_delta = timespec64_sub(ts_new, timekeeping_suspend_time);
0fa88cb4 1662 sleeptime_injected = true;
8524070b 1663 }
e445cf1c 1664
0fa88cb4 1665 if (sleeptime_injected)
e445cf1c
FT
1666 __timekeeping_inject_sleeptime(tk, &ts_delta);
1667
1668 /* Re-base the last cycle value */
876e7881 1669 tk->tkr_mono.cycle_last = cycle_now;
4a4ad80d
PZ
1670 tk->tkr_raw.cycle_last = cycle_now;
1671
4e250fdd 1672 tk->ntp_error = 0;
8524070b 1673 timekeeping_suspended = 0;
780427f0 1674 timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
3fdb14fd 1675 write_seqcount_end(&tk_core.seq);
9a7a71b1 1676 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
8524070b 1677
1678 touch_softlockup_watchdog();
1679
4ffee521 1680 tick_resume();
b12a03ce 1681 hrtimers_resume();
8524070b 1682}
1683
124cf911 1684int timekeeping_suspend(void)
8524070b 1685{
3fdb14fd 1686 struct timekeeper *tk = &tk_core.timekeeper;
92c1d3ed 1687 unsigned long flags;
7d489d15
JS
1688 struct timespec64 delta, delta_delta;
1689 static struct timespec64 old_delta;
8524070b 1690
2ee96632 1691 read_persistent_clock64(&timekeeping_suspend_time);
3be90950 1692
0d6bd995
ZM
1693 /*
1694 * On some systems the persistent_clock can not be detected at
1695 * timekeeping_init by its return value, so if we see a valid
1696 * value returned, update the persistent_clock_exists flag.
1697 */
1698 if (timekeeping_suspend_time.tv_sec || timekeeping_suspend_time.tv_nsec)
0fa88cb4 1699 persistent_clock_exists = true;
0d6bd995 1700
9a7a71b1 1701 raw_spin_lock_irqsave(&timekeeper_lock, flags);
3fdb14fd 1702 write_seqcount_begin(&tk_core.seq);
4e250fdd 1703 timekeeping_forward_now(tk);
8524070b 1704 timekeeping_suspended = 1;
cb33217b 1705
0fa88cb4 1706 if (persistent_clock_exists) {
cb33217b 1707 /*
264bb3f7
XP
1708 * To avoid drift caused by repeated suspend/resumes,
1709 * which each can add ~1 second drift error,
1710 * try to compensate so the difference in system time
1711 * and persistent_clock time stays close to constant.
cb33217b 1712 */
264bb3f7
XP
1713 delta = timespec64_sub(tk_xtime(tk), timekeeping_suspend_time);
1714 delta_delta = timespec64_sub(delta, old_delta);
1715 if (abs(delta_delta.tv_sec) >= 2) {
1716 /*
1717 * if delta_delta is too large, assume time correction
1718 * has occurred and set old_delta to the current delta.
1719 */
1720 old_delta = delta;
1721 } else {
1722 /* Otherwise try to adjust old_system to compensate */
1723 timekeeping_suspend_time =
1724 timespec64_add(timekeeping_suspend_time, delta_delta);
1725 }
cb33217b 1726 }
330a1617
JS
1727
1728 timekeeping_update(tk, TK_MIRROR);
060407ae 1729 halt_fast_timekeeper(tk);
3fdb14fd 1730 write_seqcount_end(&tk_core.seq);
9a7a71b1 1731 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
8524070b 1732
4ffee521 1733 tick_suspend();
c54a42b1 1734 clocksource_suspend();
adc78e6b 1735 clockevents_suspend();
8524070b 1736
1737 return 0;
1738}
1739
1740/* sysfs resume/suspend bits for timekeeping */
e1a85b2c 1741static struct syscore_ops timekeeping_syscore_ops = {
8524070b 1742 .resume = timekeeping_resume,
1743 .suspend = timekeeping_suspend,
8524070b 1744};
1745
e1a85b2c 1746static int __init timekeeping_init_ops(void)
8524070b 1747{
e1a85b2c
RW
1748 register_syscore_ops(&timekeeping_syscore_ops);
1749 return 0;
8524070b 1750}
e1a85b2c 1751device_initcall(timekeeping_init_ops);
8524070b 1752
1753/*
dc491596 1754 * Apply a multiplier adjustment to the timekeeper
8524070b 1755 */
dc491596
JS
1756static __always_inline void timekeeping_apply_adjustment(struct timekeeper *tk,
1757 s64 offset,
1758 bool negative,
1759 int adj_scale)
8524070b 1760{
dc491596
JS
1761 s64 interval = tk->cycle_interval;
1762 s32 mult_adj = 1;
8524070b 1763
dc491596
JS
1764 if (negative) {
1765 mult_adj = -mult_adj;
1766 interval = -interval;
1767 offset = -offset;
1d17d174 1768 }
dc491596
JS
1769 mult_adj <<= adj_scale;
1770 interval <<= adj_scale;
1771 offset <<= adj_scale;
8524070b 1772
c2bc1111
JS
1773 /*
1774 * So the following can be confusing.
1775 *
dc491596 1776 * To keep things simple, lets assume mult_adj == 1 for now.
c2bc1111 1777 *
dc491596 1778 * When mult_adj != 1, remember that the interval and offset values
c2bc1111
JS
1779 * have been appropriately scaled so the math is the same.
1780 *
1781 * The basic idea here is that we're increasing the multiplier
1782 * by one, this causes the xtime_interval to be incremented by
1783 * one cycle_interval. This is because:
1784 * xtime_interval = cycle_interval * mult
1785 * So if mult is being incremented by one:
1786 * xtime_interval = cycle_interval * (mult + 1)
1787 * Its the same as:
1788 * xtime_interval = (cycle_interval * mult) + cycle_interval
1789 * Which can be shortened to:
1790 * xtime_interval += cycle_interval
1791 *
1792 * So offset stores the non-accumulated cycles. Thus the current
1793 * time (in shifted nanoseconds) is:
1794 * now = (offset * adj) + xtime_nsec
1795 * Now, even though we're adjusting the clock frequency, we have
1796 * to keep time consistent. In other words, we can't jump back
1797 * in time, and we also want to avoid jumping forward in time.
1798 *
1799 * So given the same offset value, we need the time to be the same
1800 * both before and after the freq adjustment.
1801 * now = (offset * adj_1) + xtime_nsec_1
1802 * now = (offset * adj_2) + xtime_nsec_2
1803 * So:
1804 * (offset * adj_1) + xtime_nsec_1 =
1805 * (offset * adj_2) + xtime_nsec_2
1806 * And we know:
1807 * adj_2 = adj_1 + 1
1808 * So:
1809 * (offset * adj_1) + xtime_nsec_1 =
1810 * (offset * (adj_1+1)) + xtime_nsec_2
1811 * (offset * adj_1) + xtime_nsec_1 =
1812 * (offset * adj_1) + offset + xtime_nsec_2
1813 * Canceling the sides:
1814 * xtime_nsec_1 = offset + xtime_nsec_2
1815 * Which gives us:
1816 * xtime_nsec_2 = xtime_nsec_1 - offset
1817 * Which simplfies to:
1818 * xtime_nsec -= offset
1819 *
1820 * XXX - TODO: Doc ntp_error calculation.
1821 */
876e7881 1822 if ((mult_adj > 0) && (tk->tkr_mono.mult + mult_adj < mult_adj)) {
6067dc5a 1823 /* NTP adjustment caused clocksource mult overflow */
1824 WARN_ON_ONCE(1);
1825 return;
1826 }
1827
876e7881 1828 tk->tkr_mono.mult += mult_adj;
f726a697 1829 tk->xtime_interval += interval;
876e7881 1830 tk->tkr_mono.xtime_nsec -= offset;
f726a697 1831 tk->ntp_error -= (interval - offset) << tk->ntp_error_shift;
dc491596
JS
1832}
1833
1834/*
1835 * Calculate the multiplier adjustment needed to match the frequency
1836 * specified by NTP
1837 */
1838static __always_inline void timekeeping_freqadjust(struct timekeeper *tk,
1839 s64 offset)
1840{
1841 s64 interval = tk->cycle_interval;
1842 s64 xinterval = tk->xtime_interval;
ec02b076
JS
1843 u32 base = tk->tkr_mono.clock->mult;
1844 u32 max = tk->tkr_mono.clock->maxadj;
1845 u32 cur_adj = tk->tkr_mono.mult;
dc491596
JS
1846 s64 tick_error;
1847 bool negative;
ec02b076 1848 u32 adj_scale;
dc491596
JS
1849
1850 /* Remove any current error adj from freq calculation */
1851 if (tk->ntp_err_mult)
1852 xinterval -= tk->cycle_interval;
1853
375f45b5
JS
1854 tk->ntp_tick = ntp_tick_length();
1855
dc491596
JS
1856 /* Calculate current error per tick */
1857 tick_error = ntp_tick_length() >> tk->ntp_error_shift;
1858 tick_error -= (xinterval + tk->xtime_remainder);
1859
1860 /* Don't worry about correcting it if its small */
1861 if (likely((tick_error >= 0) && (tick_error <= interval)))
1862 return;
1863
1864 /* preserve the direction of correction */
1865 negative = (tick_error < 0);
1866
ec02b076
JS
1867 /* If any adjustment would pass the max, just return */
1868 if (negative && (cur_adj - 1) <= (base - max))
1869 return;
1870 if (!negative && (cur_adj + 1) >= (base + max))
1871 return;
1872 /*
1873 * Sort out the magnitude of the correction, but
1874 * avoid making so large a correction that we go
1875 * over the max adjustment.
1876 */
1877 adj_scale = 0;
79211c8e 1878 tick_error = abs(tick_error);
ec02b076
JS
1879 while (tick_error > interval) {
1880 u32 adj = 1 << (adj_scale + 1);
1881
1882 /* Check if adjustment gets us within 1 unit from the max */
1883 if (negative && (cur_adj - adj) <= (base - max))
1884 break;
1885 if (!negative && (cur_adj + adj) >= (base + max))
1886 break;
1887
1888 adj_scale++;
dc491596 1889 tick_error >>= 1;
ec02b076 1890 }
dc491596
JS
1891
1892 /* scale the corrections */
ec02b076 1893 timekeeping_apply_adjustment(tk, offset, negative, adj_scale);
dc491596
JS
1894}
1895
1896/*
1897 * Adjust the timekeeper's multiplier to the correct frequency
1898 * and also to reduce the accumulated error value.
1899 */
1900static void timekeeping_adjust(struct timekeeper *tk, s64 offset)
1901{
1902 /* Correct for the current frequency error */
1903 timekeeping_freqadjust(tk, offset);
1904
1905 /* Next make a small adjustment to fix any cumulative error */
1906 if (!tk->ntp_err_mult && (tk->ntp_error > 0)) {
1907 tk->ntp_err_mult = 1;
1908 timekeeping_apply_adjustment(tk, offset, 0, 0);
1909 } else if (tk->ntp_err_mult && (tk->ntp_error <= 0)) {
1910 /* Undo any existing error adjustment */
1911 timekeeping_apply_adjustment(tk, offset, 1, 0);
1912 tk->ntp_err_mult = 0;
1913 }
1914
876e7881
PZ
1915 if (unlikely(tk->tkr_mono.clock->maxadj &&
1916 (abs(tk->tkr_mono.mult - tk->tkr_mono.clock->mult)
1917 > tk->tkr_mono.clock->maxadj))) {
dc491596
JS
1918 printk_once(KERN_WARNING
1919 "Adjusting %s more than 11%% (%ld vs %ld)\n",
876e7881
PZ
1920 tk->tkr_mono.clock->name, (long)tk->tkr_mono.mult,
1921 (long)tk->tkr_mono.clock->mult + tk->tkr_mono.clock->maxadj);
dc491596 1922 }
2a8c0883
JS
1923
1924 /*
1925 * It may be possible that when we entered this function, xtime_nsec
1926 * was very small. Further, if we're slightly speeding the clocksource
1927 * in the code above, its possible the required corrective factor to
1928 * xtime_nsec could cause it to underflow.
1929 *
1930 * Now, since we already accumulated the second, cannot simply roll
1931 * the accumulated second back, since the NTP subsystem has been
1932 * notified via second_overflow. So instead we push xtime_nsec forward
1933 * by the amount we underflowed, and add that amount into the error.
1934 *
1935 * We'll correct this error next time through this function, when
1936 * xtime_nsec is not as small.
1937 */
876e7881
PZ
1938 if (unlikely((s64)tk->tkr_mono.xtime_nsec < 0)) {
1939 s64 neg = -(s64)tk->tkr_mono.xtime_nsec;
1940 tk->tkr_mono.xtime_nsec = 0;
f726a697 1941 tk->ntp_error += neg << tk->ntp_error_shift;
2a8c0883 1942 }
8524070b 1943}
1944
1f4f9487
JS
1945/**
1946 * accumulate_nsecs_to_secs - Accumulates nsecs into secs
1947 *
571af55a 1948 * Helper function that accumulates the nsecs greater than a second
1f4f9487
JS
1949 * from the xtime_nsec field to the xtime_secs field.
1950 * It also calls into the NTP code to handle leapsecond processing.
1951 *
1952 */
780427f0 1953static inline unsigned int accumulate_nsecs_to_secs(struct timekeeper *tk)
1f4f9487 1954{
876e7881 1955 u64 nsecps = (u64)NSEC_PER_SEC << tk->tkr_mono.shift;
5258d3f2 1956 unsigned int clock_set = 0;
1f4f9487 1957
876e7881 1958 while (tk->tkr_mono.xtime_nsec >= nsecps) {
1f4f9487
JS
1959 int leap;
1960
876e7881 1961 tk->tkr_mono.xtime_nsec -= nsecps;
1f4f9487
JS
1962 tk->xtime_sec++;
1963
1964 /* Figure out if its a leap sec and apply if needed */
1965 leap = second_overflow(tk->xtime_sec);
6d0ef903 1966 if (unlikely(leap)) {
7d489d15 1967 struct timespec64 ts;
6d0ef903
JS
1968
1969 tk->xtime_sec += leap;
1f4f9487 1970
6d0ef903
JS
1971 ts.tv_sec = leap;
1972 ts.tv_nsec = 0;
1973 tk_set_wall_to_mono(tk,
7d489d15 1974 timespec64_sub(tk->wall_to_monotonic, ts));
6d0ef903 1975
cc244dda
JS
1976 __timekeeping_set_tai_offset(tk, tk->tai_offset - leap);
1977
5258d3f2 1978 clock_set = TK_CLOCK_WAS_SET;
6d0ef903 1979 }
1f4f9487 1980 }
5258d3f2 1981 return clock_set;
1f4f9487
JS
1982}
1983
a092ff0f 1984/**
1985 * logarithmic_accumulation - shifted accumulation of cycles
1986 *
1987 * This functions accumulates a shifted interval of cycles into
1988 * into a shifted interval nanoseconds. Allows for O(log) accumulation
1989 * loop.
1990 *
1991 * Returns the unconsumed cycles.
1992 */
f726a697 1993static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset,
5258d3f2
JS
1994 u32 shift,
1995 unsigned int *clock_set)
a092ff0f 1996{
23a9537a 1997 cycle_t interval = tk->cycle_interval << shift;
deda2e81 1998 u64 raw_nsecs;
a092ff0f 1999
571af55a 2000 /* If the offset is smaller than a shifted interval, do nothing */
23a9537a 2001 if (offset < interval)
a092ff0f 2002 return offset;
2003
2004 /* Accumulate one shifted interval */
23a9537a 2005 offset -= interval;
876e7881 2006 tk->tkr_mono.cycle_last += interval;
4a4ad80d 2007 tk->tkr_raw.cycle_last += interval;
a092ff0f 2008
876e7881 2009 tk->tkr_mono.xtime_nsec += tk->xtime_interval << shift;
5258d3f2 2010 *clock_set |= accumulate_nsecs_to_secs(tk);
a092ff0f 2011
deda2e81 2012 /* Accumulate raw time */
5b3900cd 2013 raw_nsecs = (u64)tk->raw_interval << shift;
f726a697 2014 raw_nsecs += tk->raw_time.tv_nsec;
c7dcf87a
JS
2015 if (raw_nsecs >= NSEC_PER_SEC) {
2016 u64 raw_secs = raw_nsecs;
2017 raw_nsecs = do_div(raw_secs, NSEC_PER_SEC);
f726a697 2018 tk->raw_time.tv_sec += raw_secs;
a092ff0f 2019 }
f726a697 2020 tk->raw_time.tv_nsec = raw_nsecs;
a092ff0f 2021
2022 /* Accumulate error between NTP and clock interval */
375f45b5 2023 tk->ntp_error += tk->ntp_tick << shift;
f726a697
JS
2024 tk->ntp_error -= (tk->xtime_interval + tk->xtime_remainder) <<
2025 (tk->ntp_error_shift + shift);
a092ff0f 2026
2027 return offset;
2028}
2029
8524070b 2030/**
2031 * update_wall_time - Uses the current clocksource to increment the wall time
2032 *
8524070b 2033 */
47a1b796 2034void update_wall_time(void)
8524070b 2035{
3fdb14fd 2036 struct timekeeper *real_tk = &tk_core.timekeeper;
48cdc135 2037 struct timekeeper *tk = &shadow_timekeeper;
8524070b 2038 cycle_t offset;
a092ff0f 2039 int shift = 0, maxshift;
5258d3f2 2040 unsigned int clock_set = 0;
70471f2f
JS
2041 unsigned long flags;
2042
9a7a71b1 2043 raw_spin_lock_irqsave(&timekeeper_lock, flags);
8524070b 2044
2045 /* Make sure we're fully resumed: */
2046 if (unlikely(timekeeping_suspended))
70471f2f 2047 goto out;
8524070b 2048
592913ec 2049#ifdef CONFIG_ARCH_USES_GETTIMEOFFSET
48cdc135 2050 offset = real_tk->cycle_interval;
592913ec 2051#else
876e7881
PZ
2052 offset = clocksource_delta(tk->tkr_mono.read(tk->tkr_mono.clock),
2053 tk->tkr_mono.cycle_last, tk->tkr_mono.mask);
8524070b 2054#endif
8524070b 2055
bf2ac312 2056 /* Check if there's really nothing to do */
48cdc135 2057 if (offset < real_tk->cycle_interval)
bf2ac312
JS
2058 goto out;
2059
3c17ad19
JS
2060 /* Do some additional sanity checking */
2061 timekeeping_check_update(real_tk, offset);
2062
a092ff0f 2063 /*
2064 * With NO_HZ we may have to accumulate many cycle_intervals
2065 * (think "ticks") worth of time at once. To do this efficiently,
2066 * we calculate the largest doubling multiple of cycle_intervals
88b28adf 2067 * that is smaller than the offset. We then accumulate that
a092ff0f 2068 * chunk in one go, and then try to consume the next smaller
2069 * doubled multiple.
8524070b 2070 */
4e250fdd 2071 shift = ilog2(offset) - ilog2(tk->cycle_interval);
a092ff0f 2072 shift = max(0, shift);
88b28adf 2073 /* Bound shift to one less than what overflows tick_length */
ea7cf49a 2074 maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1;
a092ff0f 2075 shift = min(shift, maxshift);
4e250fdd 2076 while (offset >= tk->cycle_interval) {
5258d3f2
JS
2077 offset = logarithmic_accumulation(tk, offset, shift,
2078 &clock_set);
4e250fdd 2079 if (offset < tk->cycle_interval<<shift)
830ec045 2080 shift--;
8524070b 2081 }
2082
2083 /* correct the clock when NTP error is too big */
4e250fdd 2084 timekeeping_adjust(tk, offset);
8524070b 2085
6a867a39 2086 /*
92bb1fcf
JS
2087 * XXX This can be killed once everyone converts
2088 * to the new update_vsyscall.
2089 */
2090 old_vsyscall_fixup(tk);
8524070b 2091
6a867a39
JS
2092 /*
2093 * Finally, make sure that after the rounding
1e75fa8b 2094 * xtime_nsec isn't larger than NSEC_PER_SEC
6a867a39 2095 */
5258d3f2 2096 clock_set |= accumulate_nsecs_to_secs(tk);
83f57a11 2097
3fdb14fd 2098 write_seqcount_begin(&tk_core.seq);
48cdc135
TG
2099 /*
2100 * Update the real timekeeper.
2101 *
2102 * We could avoid this memcpy by switching pointers, but that
2103 * requires changes to all other timekeeper usage sites as
2104 * well, i.e. move the timekeeper pointer getter into the
2105 * spinlocked/seqcount protected sections. And we trade this
3fdb14fd 2106 * memcpy under the tk_core.seq against one before we start
48cdc135
TG
2107 * updating.
2108 */
906c5557 2109 timekeeping_update(tk, clock_set);
48cdc135 2110 memcpy(real_tk, tk, sizeof(*tk));
906c5557 2111 /* The memcpy must come last. Do not put anything here! */
3fdb14fd 2112 write_seqcount_end(&tk_core.seq);
ca4523cd 2113out:
9a7a71b1 2114 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
47a1b796 2115 if (clock_set)
cab5e127
JS
2116 /* Have to call _delayed version, since in irq context*/
2117 clock_was_set_delayed();
8524070b 2118}
7c3f1a57
TJ
2119
2120/**
d08c0cdd
JS
2121 * getboottime64 - Return the real time of system boot.
2122 * @ts: pointer to the timespec64 to be set
7c3f1a57 2123 *
d08c0cdd 2124 * Returns the wall-time of boot in a timespec64.
7c3f1a57
TJ
2125 *
2126 * This is based on the wall_to_monotonic offset and the total suspend
2127 * time. Calls to settimeofday will affect the value returned (which
2128 * basically means that however wrong your real time clock is at boot time,
2129 * you get the right time here).
2130 */
d08c0cdd 2131void getboottime64(struct timespec64 *ts)
7c3f1a57 2132{
3fdb14fd 2133 struct timekeeper *tk = &tk_core.timekeeper;
02cba159
TG
2134 ktime_t t = ktime_sub(tk->offs_real, tk->offs_boot);
2135
d08c0cdd 2136 *ts = ktime_to_timespec64(t);
7c3f1a57 2137}
d08c0cdd 2138EXPORT_SYMBOL_GPL(getboottime64);
7c3f1a57 2139
17c38b74 2140unsigned long get_seconds(void)
2141{
3fdb14fd 2142 struct timekeeper *tk = &tk_core.timekeeper;
4e250fdd
JS
2143
2144 return tk->xtime_sec;
17c38b74 2145}
2146EXPORT_SYMBOL(get_seconds);
2147
da15cfda 2148struct timespec __current_kernel_time(void)
2149{
3fdb14fd 2150 struct timekeeper *tk = &tk_core.timekeeper;
4e250fdd 2151
7d489d15 2152 return timespec64_to_timespec(tk_xtime(tk));
da15cfda 2153}
17c38b74 2154
8758a240 2155struct timespec64 current_kernel_time64(void)
2c6b47de 2156{
3fdb14fd 2157 struct timekeeper *tk = &tk_core.timekeeper;
7d489d15 2158 struct timespec64 now;
2c6b47de 2159 unsigned long seq;
2160
2161 do {
3fdb14fd 2162 seq = read_seqcount_begin(&tk_core.seq);
83f57a11 2163
4e250fdd 2164 now = tk_xtime(tk);
3fdb14fd 2165 } while (read_seqcount_retry(&tk_core.seq, seq));
2c6b47de 2166
8758a240 2167 return now;
2c6b47de 2168}
8758a240 2169EXPORT_SYMBOL(current_kernel_time64);
da15cfda 2170
334334b5 2171struct timespec64 get_monotonic_coarse64(void)
da15cfda 2172{
3fdb14fd 2173 struct timekeeper *tk = &tk_core.timekeeper;
7d489d15 2174 struct timespec64 now, mono;
da15cfda 2175 unsigned long seq;
2176
2177 do {
3fdb14fd 2178 seq = read_seqcount_begin(&tk_core.seq);
83f57a11 2179
4e250fdd
JS
2180 now = tk_xtime(tk);
2181 mono = tk->wall_to_monotonic;
3fdb14fd 2182 } while (read_seqcount_retry(&tk_core.seq, seq));
da15cfda 2183
7d489d15 2184 set_normalized_timespec64(&now, now.tv_sec + mono.tv_sec,
da15cfda 2185 now.tv_nsec + mono.tv_nsec);
7d489d15 2186
334334b5 2187 return now;
da15cfda 2188}
871cf1e5
TH
2189
2190/*
d6ad4187 2191 * Must hold jiffies_lock
871cf1e5
TH
2192 */
2193void do_timer(unsigned long ticks)
2194{
2195 jiffies_64 += ticks;
871cf1e5
TH
2196 calc_global_load(ticks);
2197}
48cf76f7 2198
f6c06abf 2199/**
76f41088 2200 * ktime_get_update_offsets_now - hrtimer helper
868a3e91 2201 * @cwsseq: pointer to check and store the clock was set sequence number
f6c06abf
TG
2202 * @offs_real: pointer to storage for monotonic -> realtime offset
2203 * @offs_boot: pointer to storage for monotonic -> boottime offset
b7bc50e4 2204 * @offs_tai: pointer to storage for monotonic -> clock tai offset
f6c06abf 2205 *
868a3e91
TG
2206 * Returns current monotonic time and updates the offsets if the
2207 * sequence number in @cwsseq and timekeeper.clock_was_set_seq are
2208 * different.
2209 *
b7bc50e4 2210 * Called from hrtimer_interrupt() or retrigger_next_event()
f6c06abf 2211 */
868a3e91
TG
2212ktime_t ktime_get_update_offsets_now(unsigned int *cwsseq, ktime_t *offs_real,
2213 ktime_t *offs_boot, ktime_t *offs_tai)
f6c06abf 2214{
3fdb14fd 2215 struct timekeeper *tk = &tk_core.timekeeper;
f6c06abf 2216 unsigned int seq;
a37c0aad
TG
2217 ktime_t base;
2218 u64 nsecs;
f6c06abf
TG
2219
2220 do {
3fdb14fd 2221 seq = read_seqcount_begin(&tk_core.seq);
f6c06abf 2222
876e7881
PZ
2223 base = tk->tkr_mono.base;
2224 nsecs = timekeeping_get_ns(&tk->tkr_mono);
833f32d7
JS
2225 base = ktime_add_ns(base, nsecs);
2226
868a3e91
TG
2227 if (*cwsseq != tk->clock_was_set_seq) {
2228 *cwsseq = tk->clock_was_set_seq;
2229 *offs_real = tk->offs_real;
2230 *offs_boot = tk->offs_boot;
2231 *offs_tai = tk->offs_tai;
2232 }
833f32d7
JS
2233
2234 /* Handle leapsecond insertion adjustments */
2235 if (unlikely(base.tv64 >= tk->next_leap_ktime.tv64))
2236 *offs_real = ktime_sub(tk->offs_real, ktime_set(1, 0));
2237
3fdb14fd 2238 } while (read_seqcount_retry(&tk_core.seq, seq));
f6c06abf 2239
833f32d7 2240 return base;
f6c06abf 2241}
f6c06abf 2242
aa6f9c59
JS
2243/**
2244 * do_adjtimex() - Accessor function to NTP __do_adjtimex function
2245 */
2246int do_adjtimex(struct timex *txc)
2247{
3fdb14fd 2248 struct timekeeper *tk = &tk_core.timekeeper;
06c017fd 2249 unsigned long flags;
7d489d15 2250 struct timespec64 ts;
4e8f8b34 2251 s32 orig_tai, tai;
e4085693
JS
2252 int ret;
2253
2254 /* Validate the data before disabling interrupts */
2255 ret = ntp_validate_timex(txc);
2256 if (ret)
2257 return ret;
2258
cef90377
JS
2259 if (txc->modes & ADJ_SETOFFSET) {
2260 struct timespec delta;
2261 delta.tv_sec = txc->time.tv_sec;
2262 delta.tv_nsec = txc->time.tv_usec;
2263 if (!(txc->modes & ADJ_NANO))
2264 delta.tv_nsec *= 1000;
2265 ret = timekeeping_inject_offset(&delta);
2266 if (ret)
2267 return ret;
2268 }
2269
d6d29896 2270 getnstimeofday64(&ts);
87ace39b 2271
06c017fd 2272 raw_spin_lock_irqsave(&timekeeper_lock, flags);
3fdb14fd 2273 write_seqcount_begin(&tk_core.seq);
06c017fd 2274
4e8f8b34 2275 orig_tai = tai = tk->tai_offset;
87ace39b 2276 ret = __do_adjtimex(txc, &ts, &tai);
aa6f9c59 2277
4e8f8b34
JS
2278 if (tai != orig_tai) {
2279 __timekeeping_set_tai_offset(tk, tai);
f55c0760 2280 timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET);
4e8f8b34 2281 }
833f32d7
JS
2282 tk_update_leap_state(tk);
2283
3fdb14fd 2284 write_seqcount_end(&tk_core.seq);
06c017fd
JS
2285 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
2286
6fdda9a9
JS
2287 if (tai != orig_tai)
2288 clock_was_set();
2289
7bd36014
JS
2290 ntp_notify_cmos_timer();
2291
87ace39b
JS
2292 return ret;
2293}
aa6f9c59
JS
2294
2295#ifdef CONFIG_NTP_PPS
2296/**
2297 * hardpps() - Accessor function to NTP __hardpps function
2298 */
7ec88e4b 2299void hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts)
aa6f9c59 2300{
06c017fd
JS
2301 unsigned long flags;
2302
2303 raw_spin_lock_irqsave(&timekeeper_lock, flags);
3fdb14fd 2304 write_seqcount_begin(&tk_core.seq);
06c017fd 2305
aa6f9c59 2306 __hardpps(phase_ts, raw_ts);
06c017fd 2307
3fdb14fd 2308 write_seqcount_end(&tk_core.seq);
06c017fd 2309 raw_spin_unlock_irqrestore(&timekeeper_lock, flags);
aa6f9c59
JS
2310}
2311EXPORT_SYMBOL(hardpps);
2312#endif
2313
f0af911a
TH
2314/**
2315 * xtime_update() - advances the timekeeping infrastructure
2316 * @ticks: number of ticks, that have elapsed since the last call.
2317 *
2318 * Must be called with interrupts disabled.
2319 */
2320void xtime_update(unsigned long ticks)
2321{
d6ad4187 2322 write_seqlock(&jiffies_lock);
f0af911a 2323 do_timer(ticks);
d6ad4187 2324 write_sequnlock(&jiffies_lock);
47a1b796 2325 update_wall_time();
f0af911a 2326}