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Commit | Line | Data |
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8524070b JS |
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 JS |
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 JS |
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> |
8524070b | 25 | |
155ec602 | 26 | |
afa14e7c | 27 | static struct timekeeper timekeeper; |
155ec602 | 28 | |
8fcce546 JS |
29 | /* flag for if timekeeping is suspended */ |
30 | int __read_mostly timekeeping_suspended; | |
31 | ||
31ade306 FT |
32 | /* Flag for if there is a persistent clock on this platform */ |
33 | bool __read_mostly persistent_clock_exist = false; | |
34 | ||
1e75fa8b JS |
35 | static inline void tk_normalize_xtime(struct timekeeper *tk) |
36 | { | |
37 | while (tk->xtime_nsec >= ((u64)NSEC_PER_SEC << tk->shift)) { | |
38 | tk->xtime_nsec -= (u64)NSEC_PER_SEC << tk->shift; | |
39 | tk->xtime_sec++; | |
40 | } | |
41 | } | |
42 | ||
1e75fa8b JS |
43 | static void tk_set_xtime(struct timekeeper *tk, const struct timespec *ts) |
44 | { | |
45 | tk->xtime_sec = ts->tv_sec; | |
b44d50dc | 46 | tk->xtime_nsec = (u64)ts->tv_nsec << tk->shift; |
1e75fa8b JS |
47 | } |
48 | ||
49 | static void tk_xtime_add(struct timekeeper *tk, const struct timespec *ts) | |
50 | { | |
51 | tk->xtime_sec += ts->tv_sec; | |
b44d50dc | 52 | tk->xtime_nsec += (u64)ts->tv_nsec << tk->shift; |
784ffcbb | 53 | tk_normalize_xtime(tk); |
1e75fa8b | 54 | } |
8fcce546 | 55 | |
6d0ef903 JS |
56 | static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec wtm) |
57 | { | |
58 | struct timespec tmp; | |
59 | ||
60 | /* | |
61 | * Verify consistency of: offset_real = -wall_to_monotonic | |
62 | * before modifying anything | |
63 | */ | |
64 | set_normalized_timespec(&tmp, -tk->wall_to_monotonic.tv_sec, | |
65 | -tk->wall_to_monotonic.tv_nsec); | |
66 | WARN_ON_ONCE(tk->offs_real.tv64 != timespec_to_ktime(tmp).tv64); | |
67 | tk->wall_to_monotonic = wtm; | |
68 | set_normalized_timespec(&tmp, -wtm.tv_sec, -wtm.tv_nsec); | |
69 | tk->offs_real = timespec_to_ktime(tmp); | |
70 | } | |
71 | ||
72 | static void tk_set_sleep_time(struct timekeeper *tk, struct timespec t) | |
73 | { | |
74 | /* Verify consistency before modifying */ | |
75 | WARN_ON_ONCE(tk->offs_boot.tv64 != timespec_to_ktime(tk->total_sleep_time).tv64); | |
76 | ||
77 | tk->total_sleep_time = t; | |
78 | tk->offs_boot = timespec_to_ktime(t); | |
79 | } | |
80 | ||
155ec602 MS |
81 | /** |
82 | * timekeeper_setup_internals - Set up internals to use clocksource clock. | |
83 | * | |
84 | * @clock: Pointer to clocksource. | |
85 | * | |
86 | * Calculates a fixed cycle/nsec interval for a given clocksource/adjustment | |
87 | * pair and interval request. | |
88 | * | |
89 | * Unless you're the timekeeping code, you should not be using this! | |
90 | */ | |
f726a697 | 91 | static void tk_setup_internals(struct timekeeper *tk, struct clocksource *clock) |
155ec602 MS |
92 | { |
93 | cycle_t interval; | |
a386b5af | 94 | u64 tmp, ntpinterval; |
1e75fa8b | 95 | struct clocksource *old_clock; |
155ec602 | 96 | |
f726a697 JS |
97 | old_clock = tk->clock; |
98 | tk->clock = clock; | |
155ec602 MS |
99 | clock->cycle_last = clock->read(clock); |
100 | ||
101 | /* Do the ns -> cycle conversion first, using original mult */ | |
102 | tmp = NTP_INTERVAL_LENGTH; | |
103 | tmp <<= clock->shift; | |
a386b5af | 104 | ntpinterval = tmp; |
0a544198 MS |
105 | tmp += clock->mult/2; |
106 | do_div(tmp, clock->mult); | |
155ec602 MS |
107 | if (tmp == 0) |
108 | tmp = 1; | |
109 | ||
110 | interval = (cycle_t) tmp; | |
f726a697 | 111 | tk->cycle_interval = interval; |
155ec602 MS |
112 | |
113 | /* Go back from cycles -> shifted ns */ | |
f726a697 JS |
114 | tk->xtime_interval = (u64) interval * clock->mult; |
115 | tk->xtime_remainder = ntpinterval - tk->xtime_interval; | |
116 | tk->raw_interval = | |
0a544198 | 117 | ((u64) interval * clock->mult) >> clock->shift; |
155ec602 | 118 | |
1e75fa8b JS |
119 | /* if changing clocks, convert xtime_nsec shift units */ |
120 | if (old_clock) { | |
121 | int shift_change = clock->shift - old_clock->shift; | |
122 | if (shift_change < 0) | |
f726a697 | 123 | tk->xtime_nsec >>= -shift_change; |
1e75fa8b | 124 | else |
f726a697 | 125 | tk->xtime_nsec <<= shift_change; |
1e75fa8b | 126 | } |
f726a697 | 127 | tk->shift = clock->shift; |
155ec602 | 128 | |
f726a697 JS |
129 | tk->ntp_error = 0; |
130 | tk->ntp_error_shift = NTP_SCALE_SHIFT - clock->shift; | |
0a544198 MS |
131 | |
132 | /* | |
133 | * The timekeeper keeps its own mult values for the currently | |
134 | * active clocksource. These value will be adjusted via NTP | |
135 | * to counteract clock drifting. | |
136 | */ | |
f726a697 | 137 | tk->mult = clock->mult; |
155ec602 | 138 | } |
8524070b | 139 | |
2ba2a305 | 140 | /* Timekeeper helper functions. */ |
7b1f6207 SW |
141 | |
142 | #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET | |
143 | u32 (*arch_gettimeoffset)(void); | |
144 | ||
145 | u32 get_arch_timeoffset(void) | |
146 | { | |
147 | if (likely(arch_gettimeoffset)) | |
148 | return arch_gettimeoffset(); | |
149 | return 0; | |
150 | } | |
151 | #else | |
152 | static inline u32 get_arch_timeoffset(void) { return 0; } | |
153 | #endif | |
154 | ||
f726a697 | 155 | static inline s64 timekeeping_get_ns(struct timekeeper *tk) |
2ba2a305 MS |
156 | { |
157 | cycle_t cycle_now, cycle_delta; | |
158 | struct clocksource *clock; | |
1e75fa8b | 159 | s64 nsec; |
2ba2a305 MS |
160 | |
161 | /* read clocksource: */ | |
f726a697 | 162 | clock = tk->clock; |
2ba2a305 MS |
163 | cycle_now = clock->read(clock); |
164 | ||
165 | /* calculate the delta since the last update_wall_time: */ | |
166 | cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; | |
167 | ||
f726a697 JS |
168 | nsec = cycle_delta * tk->mult + tk->xtime_nsec; |
169 | nsec >>= tk->shift; | |
f2a5a085 | 170 | |
7b1f6207 SW |
171 | /* If arch requires, add in get_arch_timeoffset() */ |
172 | return nsec + get_arch_timeoffset(); | |
2ba2a305 MS |
173 | } |
174 | ||
f726a697 | 175 | static inline s64 timekeeping_get_ns_raw(struct timekeeper *tk) |
2ba2a305 MS |
176 | { |
177 | cycle_t cycle_now, cycle_delta; | |
178 | struct clocksource *clock; | |
f2a5a085 | 179 | s64 nsec; |
2ba2a305 MS |
180 | |
181 | /* read clocksource: */ | |
f726a697 | 182 | clock = tk->clock; |
2ba2a305 MS |
183 | cycle_now = clock->read(clock); |
184 | ||
185 | /* calculate the delta since the last update_wall_time: */ | |
186 | cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; | |
187 | ||
f2a5a085 JS |
188 | /* convert delta to nanoseconds. */ |
189 | nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); | |
190 | ||
7b1f6207 SW |
191 | /* If arch requires, add in get_arch_timeoffset() */ |
192 | return nsec + get_arch_timeoffset(); | |
2ba2a305 MS |
193 | } |
194 | ||
e0b306fe MT |
195 | static RAW_NOTIFIER_HEAD(pvclock_gtod_chain); |
196 | ||
197 | static void update_pvclock_gtod(struct timekeeper *tk) | |
198 | { | |
199 | raw_notifier_call_chain(&pvclock_gtod_chain, 0, tk); | |
200 | } | |
201 | ||
202 | /** | |
203 | * pvclock_gtod_register_notifier - register a pvclock timedata update listener | |
204 | * | |
205 | * Must hold write on timekeeper.lock | |
206 | */ | |
207 | int pvclock_gtod_register_notifier(struct notifier_block *nb) | |
208 | { | |
209 | struct timekeeper *tk = &timekeeper; | |
210 | unsigned long flags; | |
211 | int ret; | |
212 | ||
213 | write_seqlock_irqsave(&tk->lock, flags); | |
214 | ret = raw_notifier_chain_register(&pvclock_gtod_chain, nb); | |
215 | /* update timekeeping data */ | |
216 | update_pvclock_gtod(tk); | |
217 | write_sequnlock_irqrestore(&tk->lock, flags); | |
218 | ||
219 | return ret; | |
220 | } | |
221 | EXPORT_SYMBOL_GPL(pvclock_gtod_register_notifier); | |
222 | ||
223 | /** | |
224 | * pvclock_gtod_unregister_notifier - unregister a pvclock | |
225 | * timedata update listener | |
226 | * | |
227 | * Must hold write on timekeeper.lock | |
228 | */ | |
229 | int pvclock_gtod_unregister_notifier(struct notifier_block *nb) | |
230 | { | |
231 | struct timekeeper *tk = &timekeeper; | |
232 | unsigned long flags; | |
233 | int ret; | |
234 | ||
235 | write_seqlock_irqsave(&tk->lock, flags); | |
236 | ret = raw_notifier_chain_unregister(&pvclock_gtod_chain, nb); | |
237 | write_sequnlock_irqrestore(&tk->lock, flags); | |
238 | ||
239 | return ret; | |
240 | } | |
241 | EXPORT_SYMBOL_GPL(pvclock_gtod_unregister_notifier); | |
242 | ||
cc06268c | 243 | /* must hold write on timekeeper.lock */ |
f726a697 | 244 | static void timekeeping_update(struct timekeeper *tk, bool clearntp) |
cc06268c TG |
245 | { |
246 | if (clearntp) { | |
f726a697 | 247 | tk->ntp_error = 0; |
cc06268c TG |
248 | ntp_clear(); |
249 | } | |
576094b7 | 250 | update_vsyscall(tk); |
e0b306fe | 251 | update_pvclock_gtod(tk); |
cc06268c TG |
252 | } |
253 | ||
8524070b | 254 | /** |
155ec602 | 255 | * timekeeping_forward_now - update clock to the current time |
8524070b | 256 | * |
9a055117 RZ |
257 | * Forward the current clock to update its state since the last call to |
258 | * update_wall_time(). This is useful before significant clock changes, | |
259 | * as it avoids having to deal with this time offset explicitly. | |
8524070b | 260 | */ |
f726a697 | 261 | static void timekeeping_forward_now(struct timekeeper *tk) |
8524070b JS |
262 | { |
263 | cycle_t cycle_now, cycle_delta; | |
155ec602 | 264 | struct clocksource *clock; |
9a055117 | 265 | s64 nsec; |
8524070b | 266 | |
f726a697 | 267 | clock = tk->clock; |
a0f7d48b | 268 | cycle_now = clock->read(clock); |
8524070b | 269 | cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; |
9a055117 | 270 | clock->cycle_last = cycle_now; |
8524070b | 271 | |
f726a697 | 272 | tk->xtime_nsec += cycle_delta * tk->mult; |
7d27558c | 273 | |
7b1f6207 SW |
274 | /* If arch requires, add in get_arch_timeoffset() */ |
275 | tk->xtime_nsec += (u64)get_arch_timeoffset() << tk->shift; | |
7d27558c | 276 | |
f726a697 | 277 | tk_normalize_xtime(tk); |
2d42244a | 278 | |
0a544198 | 279 | nsec = clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift); |
f726a697 | 280 | timespec_add_ns(&tk->raw_time, nsec); |
8524070b JS |
281 | } |
282 | ||
283 | /** | |
1e817fb6 | 284 | * __getnstimeofday - Returns the time of day in a timespec. |
8524070b JS |
285 | * @ts: pointer to the timespec to be set |
286 | * | |
1e817fb6 KC |
287 | * Updates the time of day in the timespec. |
288 | * Returns 0 on success, or -ve when suspended (timespec will be undefined). | |
8524070b | 289 | */ |
1e817fb6 | 290 | int __getnstimeofday(struct timespec *ts) |
8524070b | 291 | { |
4e250fdd | 292 | struct timekeeper *tk = &timekeeper; |
8524070b | 293 | unsigned long seq; |
1e75fa8b | 294 | s64 nsecs = 0; |
8524070b JS |
295 | |
296 | do { | |
4e250fdd | 297 | seq = read_seqbegin(&tk->lock); |
8524070b | 298 | |
4e250fdd | 299 | ts->tv_sec = tk->xtime_sec; |
ec145bab | 300 | nsecs = timekeeping_get_ns(tk); |
8524070b | 301 | |
4e250fdd | 302 | } while (read_seqretry(&tk->lock, seq)); |
8524070b | 303 | |
ec145bab | 304 | ts->tv_nsec = 0; |
8524070b | 305 | timespec_add_ns(ts, nsecs); |
1e817fb6 KC |
306 | |
307 | /* | |
308 | * Do not bail out early, in case there were callers still using | |
309 | * the value, even in the face of the WARN_ON. | |
310 | */ | |
311 | if (unlikely(timekeeping_suspended)) | |
312 | return -EAGAIN; | |
313 | return 0; | |
314 | } | |
315 | EXPORT_SYMBOL(__getnstimeofday); | |
316 | ||
317 | /** | |
318 | * getnstimeofday - Returns the time of day in a timespec. | |
319 | * @ts: pointer to the timespec to be set | |
320 | * | |
321 | * Returns the time of day in a timespec (WARN if suspended). | |
322 | */ | |
323 | void getnstimeofday(struct timespec *ts) | |
324 | { | |
325 | WARN_ON(__getnstimeofday(ts)); | |
8524070b | 326 | } |
8524070b JS |
327 | EXPORT_SYMBOL(getnstimeofday); |
328 | ||
951ed4d3 MS |
329 | ktime_t ktime_get(void) |
330 | { | |
4e250fdd | 331 | struct timekeeper *tk = &timekeeper; |
951ed4d3 MS |
332 | unsigned int seq; |
333 | s64 secs, nsecs; | |
334 | ||
335 | WARN_ON(timekeeping_suspended); | |
336 | ||
337 | do { | |
4e250fdd JS |
338 | seq = read_seqbegin(&tk->lock); |
339 | secs = tk->xtime_sec + tk->wall_to_monotonic.tv_sec; | |
340 | nsecs = timekeeping_get_ns(tk) + tk->wall_to_monotonic.tv_nsec; | |
951ed4d3 | 341 | |
4e250fdd | 342 | } while (read_seqretry(&tk->lock, seq)); |
951ed4d3 MS |
343 | /* |
344 | * Use ktime_set/ktime_add_ns to create a proper ktime on | |
345 | * 32-bit architectures without CONFIG_KTIME_SCALAR. | |
346 | */ | |
347 | return ktime_add_ns(ktime_set(secs, 0), nsecs); | |
348 | } | |
349 | EXPORT_SYMBOL_GPL(ktime_get); | |
350 | ||
351 | /** | |
352 | * ktime_get_ts - get the monotonic clock in timespec format | |
353 | * @ts: pointer to timespec variable | |
354 | * | |
355 | * The function calculates the monotonic clock from the realtime | |
356 | * clock and the wall_to_monotonic offset and stores the result | |
357 | * in normalized timespec format in the variable pointed to by @ts. | |
358 | */ | |
359 | void ktime_get_ts(struct timespec *ts) | |
360 | { | |
4e250fdd | 361 | struct timekeeper *tk = &timekeeper; |
951ed4d3 | 362 | struct timespec tomono; |
ec145bab | 363 | s64 nsec; |
951ed4d3 | 364 | unsigned int seq; |
951ed4d3 MS |
365 | |
366 | WARN_ON(timekeeping_suspended); | |
367 | ||
368 | do { | |
4e250fdd JS |
369 | seq = read_seqbegin(&tk->lock); |
370 | ts->tv_sec = tk->xtime_sec; | |
ec145bab | 371 | nsec = timekeeping_get_ns(tk); |
4e250fdd | 372 | tomono = tk->wall_to_monotonic; |
951ed4d3 | 373 | |
4e250fdd | 374 | } while (read_seqretry(&tk->lock, seq)); |
951ed4d3 | 375 | |
ec145bab JS |
376 | ts->tv_sec += tomono.tv_sec; |
377 | ts->tv_nsec = 0; | |
378 | timespec_add_ns(ts, nsec + tomono.tv_nsec); | |
951ed4d3 MS |
379 | } |
380 | EXPORT_SYMBOL_GPL(ktime_get_ts); | |
381 | ||
e2c18e49 AG |
382 | #ifdef CONFIG_NTP_PPS |
383 | ||
384 | /** | |
385 | * getnstime_raw_and_real - get day and raw monotonic time in timespec format | |
386 | * @ts_raw: pointer to the timespec to be set to raw monotonic time | |
387 | * @ts_real: pointer to the timespec to be set to the time of day | |
388 | * | |
389 | * This function reads both the time of day and raw monotonic time at the | |
390 | * same time atomically and stores the resulting timestamps in timespec | |
391 | * format. | |
392 | */ | |
393 | void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) | |
394 | { | |
4e250fdd | 395 | struct timekeeper *tk = &timekeeper; |
e2c18e49 AG |
396 | unsigned long seq; |
397 | s64 nsecs_raw, nsecs_real; | |
398 | ||
399 | WARN_ON_ONCE(timekeeping_suspended); | |
400 | ||
401 | do { | |
4e250fdd | 402 | seq = read_seqbegin(&tk->lock); |
e2c18e49 | 403 | |
4e250fdd JS |
404 | *ts_raw = tk->raw_time; |
405 | ts_real->tv_sec = tk->xtime_sec; | |
1e75fa8b | 406 | ts_real->tv_nsec = 0; |
e2c18e49 | 407 | |
4e250fdd JS |
408 | nsecs_raw = timekeeping_get_ns_raw(tk); |
409 | nsecs_real = timekeeping_get_ns(tk); | |
e2c18e49 | 410 | |
4e250fdd | 411 | } while (read_seqretry(&tk->lock, seq)); |
e2c18e49 AG |
412 | |
413 | timespec_add_ns(ts_raw, nsecs_raw); | |
414 | timespec_add_ns(ts_real, nsecs_real); | |
415 | } | |
416 | EXPORT_SYMBOL(getnstime_raw_and_real); | |
417 | ||
418 | #endif /* CONFIG_NTP_PPS */ | |
419 | ||
8524070b JS |
420 | /** |
421 | * do_gettimeofday - Returns the time of day in a timeval | |
422 | * @tv: pointer to the timeval to be set | |
423 | * | |
efd9ac86 | 424 | * NOTE: Users should be converted to using getnstimeofday() |
8524070b JS |
425 | */ |
426 | void do_gettimeofday(struct timeval *tv) | |
427 | { | |
428 | struct timespec now; | |
429 | ||
efd9ac86 | 430 | getnstimeofday(&now); |
8524070b JS |
431 | tv->tv_sec = now.tv_sec; |
432 | tv->tv_usec = now.tv_nsec/1000; | |
433 | } | |
8524070b | 434 | EXPORT_SYMBOL(do_gettimeofday); |
d239f49d | 435 | |
8524070b JS |
436 | /** |
437 | * do_settimeofday - Sets the time of day | |
438 | * @tv: pointer to the timespec variable containing the new time | |
439 | * | |
440 | * Sets the time of day to the new time and update NTP and notify hrtimers | |
441 | */ | |
1e6d7679 | 442 | int do_settimeofday(const struct timespec *tv) |
8524070b | 443 | { |
4e250fdd | 444 | struct timekeeper *tk = &timekeeper; |
1e75fa8b | 445 | struct timespec ts_delta, xt; |
92c1d3ed | 446 | unsigned long flags; |
8524070b | 447 | |
cee58483 | 448 | if (!timespec_valid_strict(tv)) |
8524070b JS |
449 | return -EINVAL; |
450 | ||
4e250fdd | 451 | write_seqlock_irqsave(&tk->lock, flags); |
8524070b | 452 | |
4e250fdd | 453 | timekeeping_forward_now(tk); |
9a055117 | 454 | |
4e250fdd | 455 | xt = tk_xtime(tk); |
1e75fa8b JS |
456 | ts_delta.tv_sec = tv->tv_sec - xt.tv_sec; |
457 | ts_delta.tv_nsec = tv->tv_nsec - xt.tv_nsec; | |
458 | ||
4e250fdd | 459 | tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, ts_delta)); |
8524070b | 460 | |
4e250fdd | 461 | tk_set_xtime(tk, tv); |
1e75fa8b | 462 | |
4e250fdd | 463 | timekeeping_update(tk, true); |
8524070b | 464 | |
4e250fdd | 465 | write_sequnlock_irqrestore(&tk->lock, flags); |
8524070b JS |
466 | |
467 | /* signal hrtimers about time change */ | |
468 | clock_was_set(); | |
469 | ||
470 | return 0; | |
471 | } | |
8524070b JS |
472 | EXPORT_SYMBOL(do_settimeofday); |
473 | ||
c528f7c6 JS |
474 | /** |
475 | * timekeeping_inject_offset - Adds or subtracts from the current time. | |
476 | * @tv: pointer to the timespec variable containing the offset | |
477 | * | |
478 | * Adds or subtracts an offset value from the current time. | |
479 | */ | |
480 | int timekeeping_inject_offset(struct timespec *ts) | |
481 | { | |
4e250fdd | 482 | struct timekeeper *tk = &timekeeper; |
92c1d3ed | 483 | unsigned long flags; |
4e8b1452 JS |
484 | struct timespec tmp; |
485 | int ret = 0; | |
c528f7c6 JS |
486 | |
487 | if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC) | |
488 | return -EINVAL; | |
489 | ||
4e250fdd | 490 | write_seqlock_irqsave(&tk->lock, flags); |
c528f7c6 | 491 | |
4e250fdd | 492 | timekeeping_forward_now(tk); |
c528f7c6 | 493 | |
4e8b1452 JS |
494 | /* Make sure the proposed value is valid */ |
495 | tmp = timespec_add(tk_xtime(tk), *ts); | |
cee58483 | 496 | if (!timespec_valid_strict(&tmp)) { |
4e8b1452 JS |
497 | ret = -EINVAL; |
498 | goto error; | |
499 | } | |
1e75fa8b | 500 | |
4e250fdd JS |
501 | tk_xtime_add(tk, ts); |
502 | tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, *ts)); | |
c528f7c6 | 503 | |
4e8b1452 | 504 | error: /* even if we error out, we forwarded the time, so call update */ |
4e250fdd | 505 | timekeeping_update(tk, true); |
c528f7c6 | 506 | |
4e250fdd | 507 | write_sequnlock_irqrestore(&tk->lock, flags); |
c528f7c6 JS |
508 | |
509 | /* signal hrtimers about time change */ | |
510 | clock_was_set(); | |
511 | ||
4e8b1452 | 512 | return ret; |
c528f7c6 JS |
513 | } |
514 | EXPORT_SYMBOL(timekeeping_inject_offset); | |
515 | ||
cc244dda JS |
516 | |
517 | /** | |
518 | * timekeeping_get_tai_offset - Returns current TAI offset from UTC | |
519 | * | |
520 | */ | |
521 | s32 timekeeping_get_tai_offset(void) | |
522 | { | |
523 | struct timekeeper *tk = &timekeeper; | |
524 | unsigned int seq; | |
525 | s32 ret; | |
526 | ||
527 | do { | |
528 | seq = read_seqbegin(&tk->lock); | |
529 | ret = tk->tai_offset; | |
530 | } while (read_seqretry(&tk->lock, seq)); | |
531 | ||
532 | return ret; | |
533 | } | |
534 | ||
535 | /** | |
536 | * __timekeeping_set_tai_offset - Lock free worker function | |
537 | * | |
538 | */ | |
539 | void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset) | |
540 | { | |
541 | tk->tai_offset = tai_offset; | |
542 | } | |
543 | ||
544 | /** | |
545 | * timekeeping_set_tai_offset - Sets the current TAI offset from UTC | |
546 | * | |
547 | */ | |
548 | void timekeeping_set_tai_offset(s32 tai_offset) | |
549 | { | |
550 | struct timekeeper *tk = &timekeeper; | |
551 | unsigned long flags; | |
552 | ||
553 | write_seqlock_irqsave(&tk->lock, flags); | |
554 | __timekeeping_set_tai_offset(tk, tai_offset); | |
555 | write_sequnlock_irqrestore(&tk->lock, flags); | |
556 | } | |
557 | ||
8524070b JS |
558 | /** |
559 | * change_clocksource - Swaps clocksources if a new one is available | |
560 | * | |
561 | * Accumulates current time interval and initializes new clocksource | |
562 | */ | |
75c5158f | 563 | static int change_clocksource(void *data) |
8524070b | 564 | { |
4e250fdd | 565 | struct timekeeper *tk = &timekeeper; |
4614e6ad | 566 | struct clocksource *new, *old; |
f695cf94 | 567 | unsigned long flags; |
8524070b | 568 | |
75c5158f | 569 | new = (struct clocksource *) data; |
8524070b | 570 | |
4e250fdd | 571 | write_seqlock_irqsave(&tk->lock, flags); |
f695cf94 | 572 | |
4e250fdd | 573 | timekeeping_forward_now(tk); |
75c5158f | 574 | if (!new->enable || new->enable(new) == 0) { |
4e250fdd JS |
575 | old = tk->clock; |
576 | tk_setup_internals(tk, new); | |
75c5158f MS |
577 | if (old->disable) |
578 | old->disable(old); | |
579 | } | |
4e250fdd | 580 | timekeeping_update(tk, true); |
f695cf94 | 581 | |
4e250fdd | 582 | write_sequnlock_irqrestore(&tk->lock, flags); |
f695cf94 | 583 | |
75c5158f MS |
584 | return 0; |
585 | } | |
8524070b | 586 | |
75c5158f MS |
587 | /** |
588 | * timekeeping_notify - Install a new clock source | |
589 | * @clock: pointer to the clock source | |
590 | * | |
591 | * This function is called from clocksource.c after a new, better clock | |
592 | * source has been registered. The caller holds the clocksource_mutex. | |
593 | */ | |
594 | void timekeeping_notify(struct clocksource *clock) | |
595 | { | |
4e250fdd JS |
596 | struct timekeeper *tk = &timekeeper; |
597 | ||
598 | if (tk->clock == clock) | |
4614e6ad | 599 | return; |
75c5158f | 600 | stop_machine(change_clocksource, clock, NULL); |
8524070b | 601 | tick_clock_notify(); |
8524070b | 602 | } |
75c5158f | 603 | |
a40f262c TG |
604 | /** |
605 | * ktime_get_real - get the real (wall-) time in ktime_t format | |
606 | * | |
607 | * returns the time in ktime_t format | |
608 | */ | |
609 | ktime_t ktime_get_real(void) | |
610 | { | |
611 | struct timespec now; | |
612 | ||
613 | getnstimeofday(&now); | |
614 | ||
615 | return timespec_to_ktime(now); | |
616 | } | |
617 | EXPORT_SYMBOL_GPL(ktime_get_real); | |
8524070b | 618 | |
2d42244a JS |
619 | /** |
620 | * getrawmonotonic - Returns the raw monotonic time in a timespec | |
621 | * @ts: pointer to the timespec to be set | |
622 | * | |
623 | * Returns the raw monotonic time (completely un-modified by ntp) | |
624 | */ | |
625 | void getrawmonotonic(struct timespec *ts) | |
626 | { | |
4e250fdd | 627 | struct timekeeper *tk = &timekeeper; |
2d42244a JS |
628 | unsigned long seq; |
629 | s64 nsecs; | |
2d42244a JS |
630 | |
631 | do { | |
4e250fdd JS |
632 | seq = read_seqbegin(&tk->lock); |
633 | nsecs = timekeeping_get_ns_raw(tk); | |
634 | *ts = tk->raw_time; | |
2d42244a | 635 | |
4e250fdd | 636 | } while (read_seqretry(&tk->lock, seq)); |
2d42244a JS |
637 | |
638 | timespec_add_ns(ts, nsecs); | |
639 | } | |
640 | EXPORT_SYMBOL(getrawmonotonic); | |
641 | ||
8524070b | 642 | /** |
cf4fc6cb | 643 | * timekeeping_valid_for_hres - Check if timekeeping is suitable for hres |
8524070b | 644 | */ |
cf4fc6cb | 645 | int timekeeping_valid_for_hres(void) |
8524070b | 646 | { |
4e250fdd | 647 | struct timekeeper *tk = &timekeeper; |
8524070b JS |
648 | unsigned long seq; |
649 | int ret; | |
650 | ||
651 | do { | |
4e250fdd | 652 | seq = read_seqbegin(&tk->lock); |
8524070b | 653 | |
4e250fdd | 654 | ret = tk->clock->flags & CLOCK_SOURCE_VALID_FOR_HRES; |
8524070b | 655 | |
4e250fdd | 656 | } while (read_seqretry(&tk->lock, seq)); |
8524070b JS |
657 | |
658 | return ret; | |
659 | } | |
660 | ||
98962465 JH |
661 | /** |
662 | * timekeeping_max_deferment - Returns max time the clocksource can be deferred | |
98962465 JH |
663 | */ |
664 | u64 timekeeping_max_deferment(void) | |
665 | { | |
4e250fdd | 666 | struct timekeeper *tk = &timekeeper; |
70471f2f JS |
667 | unsigned long seq; |
668 | u64 ret; | |
42e71e81 | 669 | |
70471f2f | 670 | do { |
4e250fdd | 671 | seq = read_seqbegin(&tk->lock); |
70471f2f | 672 | |
4e250fdd | 673 | ret = tk->clock->max_idle_ns; |
70471f2f | 674 | |
4e250fdd | 675 | } while (read_seqretry(&tk->lock, seq)); |
70471f2f JS |
676 | |
677 | return ret; | |
98962465 JH |
678 | } |
679 | ||
8524070b | 680 | /** |
d4f587c6 | 681 | * read_persistent_clock - Return time from the persistent clock. |
8524070b JS |
682 | * |
683 | * Weak dummy function for arches that do not yet support it. | |
d4f587c6 MS |
684 | * Reads the time from the battery backed persistent clock. |
685 | * Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported. | |
8524070b JS |
686 | * |
687 | * XXX - Do be sure to remove it once all arches implement it. | |
688 | */ | |
d4f587c6 | 689 | void __attribute__((weak)) read_persistent_clock(struct timespec *ts) |
8524070b | 690 | { |
d4f587c6 MS |
691 | ts->tv_sec = 0; |
692 | ts->tv_nsec = 0; | |
8524070b JS |
693 | } |
694 | ||
23970e38 MS |
695 | /** |
696 | * read_boot_clock - Return time of the system start. | |
697 | * | |
698 | * Weak dummy function for arches that do not yet support it. | |
699 | * Function to read the exact time the system has been started. | |
700 | * Returns a timespec with tv_sec=0 and tv_nsec=0 if unsupported. | |
701 | * | |
702 | * XXX - Do be sure to remove it once all arches implement it. | |
703 | */ | |
704 | void __attribute__((weak)) read_boot_clock(struct timespec *ts) | |
705 | { | |
706 | ts->tv_sec = 0; | |
707 | ts->tv_nsec = 0; | |
708 | } | |
709 | ||
8524070b JS |
710 | /* |
711 | * timekeeping_init - Initializes the clocksource and common timekeeping values | |
712 | */ | |
713 | void __init timekeeping_init(void) | |
714 | { | |
4e250fdd | 715 | struct timekeeper *tk = &timekeeper; |
155ec602 | 716 | struct clocksource *clock; |
8524070b | 717 | unsigned long flags; |
6d0ef903 | 718 | struct timespec now, boot, tmp; |
d4f587c6 MS |
719 | |
720 | read_persistent_clock(&now); | |
31ade306 | 721 | |
cee58483 | 722 | if (!timespec_valid_strict(&now)) { |
4e8b1452 JS |
723 | pr_warn("WARNING: Persistent clock returned invalid value!\n" |
724 | " Check your CMOS/BIOS settings.\n"); | |
725 | now.tv_sec = 0; | |
726 | now.tv_nsec = 0; | |
31ade306 FT |
727 | } else if (now.tv_sec || now.tv_nsec) |
728 | persistent_clock_exist = true; | |
4e8b1452 | 729 | |
23970e38 | 730 | read_boot_clock(&boot); |
cee58483 | 731 | if (!timespec_valid_strict(&boot)) { |
4e8b1452 JS |
732 | pr_warn("WARNING: Boot clock returned invalid value!\n" |
733 | " Check your CMOS/BIOS settings.\n"); | |
734 | boot.tv_sec = 0; | |
735 | boot.tv_nsec = 0; | |
736 | } | |
8524070b | 737 | |
4e250fdd | 738 | seqlock_init(&tk->lock); |
8524070b | 739 | |
7dffa3c6 | 740 | ntp_init(); |
8524070b | 741 | |
4e250fdd | 742 | write_seqlock_irqsave(&tk->lock, flags); |
f1b82746 | 743 | clock = clocksource_default_clock(); |
a0f7d48b MS |
744 | if (clock->enable) |
745 | clock->enable(clock); | |
4e250fdd | 746 | tk_setup_internals(tk, clock); |
8524070b | 747 | |
4e250fdd JS |
748 | tk_set_xtime(tk, &now); |
749 | tk->raw_time.tv_sec = 0; | |
750 | tk->raw_time.tv_nsec = 0; | |
1e75fa8b | 751 | if (boot.tv_sec == 0 && boot.tv_nsec == 0) |
4e250fdd | 752 | boot = tk_xtime(tk); |
1e75fa8b | 753 | |
6d0ef903 | 754 | set_normalized_timespec(&tmp, -boot.tv_sec, -boot.tv_nsec); |
4e250fdd | 755 | tk_set_wall_to_mono(tk, tmp); |
6d0ef903 JS |
756 | |
757 | tmp.tv_sec = 0; | |
758 | tmp.tv_nsec = 0; | |
4e250fdd | 759 | tk_set_sleep_time(tk, tmp); |
6d0ef903 | 760 | |
4e250fdd | 761 | write_sequnlock_irqrestore(&tk->lock, flags); |
8524070b JS |
762 | } |
763 | ||
8524070b | 764 | /* time in seconds when suspend began */ |
d4f587c6 | 765 | static struct timespec timekeeping_suspend_time; |
8524070b | 766 | |
304529b1 JS |
767 | /** |
768 | * __timekeeping_inject_sleeptime - Internal function to add sleep interval | |
769 | * @delta: pointer to a timespec delta value | |
770 | * | |
771 | * Takes a timespec offset measuring a suspend interval and properly | |
772 | * adds the sleep offset to the timekeeping variables. | |
773 | */ | |
f726a697 JS |
774 | static void __timekeeping_inject_sleeptime(struct timekeeper *tk, |
775 | struct timespec *delta) | |
304529b1 | 776 | { |
cee58483 | 777 | if (!timespec_valid_strict(delta)) { |
cbaa5152 | 778 | printk(KERN_WARNING "__timekeeping_inject_sleeptime: Invalid " |
cb5de2f8 JS |
779 | "sleep delta value!\n"); |
780 | return; | |
781 | } | |
f726a697 | 782 | tk_xtime_add(tk, delta); |
6d0ef903 JS |
783 | tk_set_wall_to_mono(tk, timespec_sub(tk->wall_to_monotonic, *delta)); |
784 | tk_set_sleep_time(tk, timespec_add(tk->total_sleep_time, *delta)); | |
304529b1 JS |
785 | } |
786 | ||
304529b1 JS |
787 | /** |
788 | * timekeeping_inject_sleeptime - Adds suspend interval to timeekeeping values | |
789 | * @delta: pointer to a timespec delta value | |
790 | * | |
791 | * This hook is for architectures that cannot support read_persistent_clock | |
792 | * because their RTC/persistent clock is only accessible when irqs are enabled. | |
793 | * | |
794 | * This function should only be called by rtc_resume(), and allows | |
795 | * a suspend offset to be injected into the timekeeping values. | |
796 | */ | |
797 | void timekeeping_inject_sleeptime(struct timespec *delta) | |
798 | { | |
4e250fdd | 799 | struct timekeeper *tk = &timekeeper; |
92c1d3ed | 800 | unsigned long flags; |
304529b1 | 801 | |
31ade306 FT |
802 | /* |
803 | * Make sure we don't set the clock twice, as timekeeping_resume() | |
804 | * already did it | |
805 | */ | |
806 | if (has_persistent_clock()) | |
304529b1 JS |
807 | return; |
808 | ||
4e250fdd | 809 | write_seqlock_irqsave(&tk->lock, flags); |
70471f2f | 810 | |
4e250fdd | 811 | timekeeping_forward_now(tk); |
304529b1 | 812 | |
4e250fdd | 813 | __timekeeping_inject_sleeptime(tk, delta); |
304529b1 | 814 | |
4e250fdd | 815 | timekeeping_update(tk, true); |
304529b1 | 816 | |
4e250fdd | 817 | write_sequnlock_irqrestore(&tk->lock, flags); |
304529b1 JS |
818 | |
819 | /* signal hrtimers about time change */ | |
820 | clock_was_set(); | |
821 | } | |
822 | ||
8524070b JS |
823 | /** |
824 | * timekeeping_resume - Resumes the generic timekeeping subsystem. | |
8524070b JS |
825 | * |
826 | * This is for the generic clocksource timekeeping. | |
827 | * xtime/wall_to_monotonic/jiffies/etc are | |
828 | * still managed by arch specific suspend/resume code. | |
829 | */ | |
e1a85b2c | 830 | static void timekeeping_resume(void) |
8524070b | 831 | { |
4e250fdd | 832 | struct timekeeper *tk = &timekeeper; |
e445cf1c | 833 | struct clocksource *clock = tk->clock; |
92c1d3ed | 834 | unsigned long flags; |
e445cf1c FT |
835 | struct timespec ts_new, ts_delta; |
836 | cycle_t cycle_now, cycle_delta; | |
837 | bool suspendtime_found = false; | |
d4f587c6 | 838 | |
e445cf1c | 839 | read_persistent_clock(&ts_new); |
8524070b | 840 | |
adc78e6b | 841 | clockevents_resume(); |
d10ff3fb TG |
842 | clocksource_resume(); |
843 | ||
4e250fdd | 844 | write_seqlock_irqsave(&tk->lock, flags); |
8524070b | 845 | |
e445cf1c FT |
846 | /* |
847 | * After system resumes, we need to calculate the suspended time and | |
848 | * compensate it for the OS time. There are 3 sources that could be | |
849 | * used: Nonstop clocksource during suspend, persistent clock and rtc | |
850 | * device. | |
851 | * | |
852 | * One specific platform may have 1 or 2 or all of them, and the | |
853 | * preference will be: | |
854 | * suspend-nonstop clocksource -> persistent clock -> rtc | |
855 | * The less preferred source will only be tried if there is no better | |
856 | * usable source. The rtc part is handled separately in rtc core code. | |
857 | */ | |
858 | cycle_now = clock->read(clock); | |
859 | if ((clock->flags & CLOCK_SOURCE_SUSPEND_NONSTOP) && | |
860 | cycle_now > clock->cycle_last) { | |
861 | u64 num, max = ULLONG_MAX; | |
862 | u32 mult = clock->mult; | |
863 | u32 shift = clock->shift; | |
864 | s64 nsec = 0; | |
865 | ||
866 | cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; | |
867 | ||
868 | /* | |
869 | * "cycle_delta * mutl" may cause 64 bits overflow, if the | |
870 | * suspended time is too long. In that case we need do the | |
871 | * 64 bits math carefully | |
872 | */ | |
873 | do_div(max, mult); | |
874 | if (cycle_delta > max) { | |
875 | num = div64_u64(cycle_delta, max); | |
876 | nsec = (((u64) max * mult) >> shift) * num; | |
877 | cycle_delta -= num * max; | |
878 | } | |
879 | nsec += ((u64) cycle_delta * mult) >> shift; | |
880 | ||
881 | ts_delta = ns_to_timespec(nsec); | |
882 | suspendtime_found = true; | |
883 | } else if (timespec_compare(&ts_new, &timekeeping_suspend_time) > 0) { | |
884 | ts_delta = timespec_sub(ts_new, timekeeping_suspend_time); | |
885 | suspendtime_found = true; | |
8524070b | 886 | } |
e445cf1c FT |
887 | |
888 | if (suspendtime_found) | |
889 | __timekeeping_inject_sleeptime(tk, &ts_delta); | |
890 | ||
891 | /* Re-base the last cycle value */ | |
892 | clock->cycle_last = cycle_now; | |
4e250fdd | 893 | tk->ntp_error = 0; |
8524070b | 894 | timekeeping_suspended = 0; |
4e250fdd JS |
895 | timekeeping_update(tk, false); |
896 | write_sequnlock_irqrestore(&tk->lock, flags); | |
8524070b JS |
897 | |
898 | touch_softlockup_watchdog(); | |
899 | ||
900 | clockevents_notify(CLOCK_EVT_NOTIFY_RESUME, NULL); | |
901 | ||
902 | /* Resume hrtimers */ | |
b12a03ce | 903 | hrtimers_resume(); |
8524070b JS |
904 | } |
905 | ||
e1a85b2c | 906 | static int timekeeping_suspend(void) |
8524070b | 907 | { |
4e250fdd | 908 | struct timekeeper *tk = &timekeeper; |
92c1d3ed | 909 | unsigned long flags; |
cb33217b JS |
910 | struct timespec delta, delta_delta; |
911 | static struct timespec old_delta; | |
8524070b | 912 | |
d4f587c6 | 913 | read_persistent_clock(&timekeeping_suspend_time); |
3be90950 | 914 | |
4e250fdd JS |
915 | write_seqlock_irqsave(&tk->lock, flags); |
916 | timekeeping_forward_now(tk); | |
8524070b | 917 | timekeeping_suspended = 1; |
cb33217b JS |
918 | |
919 | /* | |
920 | * To avoid drift caused by repeated suspend/resumes, | |
921 | * which each can add ~1 second drift error, | |
922 | * try to compensate so the difference in system time | |
923 | * and persistent_clock time stays close to constant. | |
924 | */ | |
4e250fdd | 925 | delta = timespec_sub(tk_xtime(tk), timekeeping_suspend_time); |
cb33217b JS |
926 | delta_delta = timespec_sub(delta, old_delta); |
927 | if (abs(delta_delta.tv_sec) >= 2) { | |
928 | /* | |
929 | * if delta_delta is too large, assume time correction | |
930 | * has occured and set old_delta to the current delta. | |
931 | */ | |
932 | old_delta = delta; | |
933 | } else { | |
934 | /* Otherwise try to adjust old_system to compensate */ | |
935 | timekeeping_suspend_time = | |
936 | timespec_add(timekeeping_suspend_time, delta_delta); | |
937 | } | |
4e250fdd | 938 | write_sequnlock_irqrestore(&tk->lock, flags); |
8524070b JS |
939 | |
940 | clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL); | |
c54a42b1 | 941 | clocksource_suspend(); |
adc78e6b | 942 | clockevents_suspend(); |
8524070b JS |
943 | |
944 | return 0; | |
945 | } | |
946 | ||
947 | /* sysfs resume/suspend bits for timekeeping */ | |
e1a85b2c | 948 | static struct syscore_ops timekeeping_syscore_ops = { |
8524070b JS |
949 | .resume = timekeeping_resume, |
950 | .suspend = timekeeping_suspend, | |
8524070b JS |
951 | }; |
952 | ||
e1a85b2c | 953 | static int __init timekeeping_init_ops(void) |
8524070b | 954 | { |
e1a85b2c RW |
955 | register_syscore_ops(&timekeeping_syscore_ops); |
956 | return 0; | |
8524070b JS |
957 | } |
958 | ||
e1a85b2c | 959 | device_initcall(timekeeping_init_ops); |
8524070b JS |
960 | |
961 | /* | |
962 | * If the error is already larger, we look ahead even further | |
963 | * to compensate for late or lost adjustments. | |
964 | */ | |
f726a697 JS |
965 | static __always_inline int timekeeping_bigadjust(struct timekeeper *tk, |
966 | s64 error, s64 *interval, | |
8524070b JS |
967 | s64 *offset) |
968 | { | |
969 | s64 tick_error, i; | |
970 | u32 look_ahead, adj; | |
971 | s32 error2, mult; | |
972 | ||
973 | /* | |
974 | * Use the current error value to determine how much to look ahead. | |
975 | * The larger the error the slower we adjust for it to avoid problems | |
976 | * with losing too many ticks, otherwise we would overadjust and | |
977 | * produce an even larger error. The smaller the adjustment the | |
978 | * faster we try to adjust for it, as lost ticks can do less harm | |
3eb05676 | 979 | * here. This is tuned so that an error of about 1 msec is adjusted |
8524070b JS |
980 | * within about 1 sec (or 2^20 nsec in 2^SHIFT_HZ ticks). |
981 | */ | |
f726a697 | 982 | error2 = tk->ntp_error >> (NTP_SCALE_SHIFT + 22 - 2 * SHIFT_HZ); |
8524070b JS |
983 | error2 = abs(error2); |
984 | for (look_ahead = 0; error2 > 0; look_ahead++) | |
985 | error2 >>= 2; | |
986 | ||
987 | /* | |
988 | * Now calculate the error in (1 << look_ahead) ticks, but first | |
989 | * remove the single look ahead already included in the error. | |
990 | */ | |
f726a697 JS |
991 | tick_error = ntp_tick_length() >> (tk->ntp_error_shift + 1); |
992 | tick_error -= tk->xtime_interval >> 1; | |
8524070b JS |
993 | error = ((error - tick_error) >> look_ahead) + tick_error; |
994 | ||
995 | /* Finally calculate the adjustment shift value. */ | |
996 | i = *interval; | |
997 | mult = 1; | |
998 | if (error < 0) { | |
999 | error = -error; | |
1000 | *interval = -*interval; | |
1001 | *offset = -*offset; | |
1002 | mult = -1; | |
1003 | } | |
1004 | for (adj = 0; error > i; adj++) | |
1005 | error >>= 1; | |
1006 | ||
1007 | *interval <<= adj; | |
1008 | *offset <<= adj; | |
1009 | return mult << adj; | |
1010 | } | |
1011 | ||
1012 | /* | |
1013 | * Adjust the multiplier to reduce the error value, | |
1014 | * this is optimized for the most common adjustments of -1,0,1, | |
1015 | * for other values we can do a bit more work. | |
1016 | */ | |
f726a697 | 1017 | static void timekeeping_adjust(struct timekeeper *tk, s64 offset) |
8524070b | 1018 | { |
f726a697 | 1019 | s64 error, interval = tk->cycle_interval; |
8524070b JS |
1020 | int adj; |
1021 | ||
c2bc1111 | 1022 | /* |
88b28adf | 1023 | * The point of this is to check if the error is greater than half |
c2bc1111 JS |
1024 | * an interval. |
1025 | * | |
1026 | * First we shift it down from NTP_SHIFT to clocksource->shifted nsecs. | |
1027 | * | |
1028 | * Note we subtract one in the shift, so that error is really error*2. | |
3f86f28f JS |
1029 | * This "saves" dividing(shifting) interval twice, but keeps the |
1030 | * (error > interval) comparison as still measuring if error is | |
88b28adf | 1031 | * larger than half an interval. |
c2bc1111 | 1032 | * |
3f86f28f | 1033 | * Note: It does not "save" on aggravation when reading the code. |
c2bc1111 | 1034 | */ |
f726a697 | 1035 | error = tk->ntp_error >> (tk->ntp_error_shift - 1); |
8524070b | 1036 | if (error > interval) { |
c2bc1111 JS |
1037 | /* |
1038 | * We now divide error by 4(via shift), which checks if | |
88b28adf | 1039 | * the error is greater than twice the interval. |
c2bc1111 JS |
1040 | * If it is greater, we need a bigadjust, if its smaller, |
1041 | * we can adjust by 1. | |
1042 | */ | |
8524070b | 1043 | error >>= 2; |
c2bc1111 JS |
1044 | /* |
1045 | * XXX - In update_wall_time, we round up to the next | |
1046 | * nanosecond, and store the amount rounded up into | |
1047 | * the error. This causes the likely below to be unlikely. | |
1048 | * | |
3f86f28f | 1049 | * The proper fix is to avoid rounding up by using |
4e250fdd | 1050 | * the high precision tk->xtime_nsec instead of |
c2bc1111 JS |
1051 | * xtime.tv_nsec everywhere. Fixing this will take some |
1052 | * time. | |
1053 | */ | |
8524070b JS |
1054 | if (likely(error <= interval)) |
1055 | adj = 1; | |
1056 | else | |
1d17d174 IM |
1057 | adj = timekeeping_bigadjust(tk, error, &interval, &offset); |
1058 | } else { | |
1059 | if (error < -interval) { | |
1060 | /* See comment above, this is just switched for the negative */ | |
1061 | error >>= 2; | |
1062 | if (likely(error >= -interval)) { | |
1063 | adj = -1; | |
1064 | interval = -interval; | |
1065 | offset = -offset; | |
1066 | } else { | |
1067 | adj = timekeeping_bigadjust(tk, error, &interval, &offset); | |
1068 | } | |
1069 | } else { | |
1070 | goto out_adjust; | |
1071 | } | |
1072 | } | |
8524070b | 1073 | |
f726a697 JS |
1074 | if (unlikely(tk->clock->maxadj && |
1075 | (tk->mult + adj > tk->clock->mult + tk->clock->maxadj))) { | |
e919cfd4 JS |
1076 | printk_once(KERN_WARNING |
1077 | "Adjusting %s more than 11%% (%ld vs %ld)\n", | |
f726a697 JS |
1078 | tk->clock->name, (long)tk->mult + adj, |
1079 | (long)tk->clock->mult + tk->clock->maxadj); | |
e919cfd4 | 1080 | } |
c2bc1111 JS |
1081 | /* |
1082 | * So the following can be confusing. | |
1083 | * | |
1084 | * To keep things simple, lets assume adj == 1 for now. | |
1085 | * | |
1086 | * When adj != 1, remember that the interval and offset values | |
1087 | * have been appropriately scaled so the math is the same. | |
1088 | * | |
1089 | * The basic idea here is that we're increasing the multiplier | |
1090 | * by one, this causes the xtime_interval to be incremented by | |
1091 | * one cycle_interval. This is because: | |
1092 | * xtime_interval = cycle_interval * mult | |
1093 | * So if mult is being incremented by one: | |
1094 | * xtime_interval = cycle_interval * (mult + 1) | |
1095 | * Its the same as: | |
1096 | * xtime_interval = (cycle_interval * mult) + cycle_interval | |
1097 | * Which can be shortened to: | |
1098 | * xtime_interval += cycle_interval | |
1099 | * | |
1100 | * So offset stores the non-accumulated cycles. Thus the current | |
1101 | * time (in shifted nanoseconds) is: | |
1102 | * now = (offset * adj) + xtime_nsec | |
1103 | * Now, even though we're adjusting the clock frequency, we have | |
1104 | * to keep time consistent. In other words, we can't jump back | |
1105 | * in time, and we also want to avoid jumping forward in time. | |
1106 | * | |
1107 | * So given the same offset value, we need the time to be the same | |
1108 | * both before and after the freq adjustment. | |
1109 | * now = (offset * adj_1) + xtime_nsec_1 | |
1110 | * now = (offset * adj_2) + xtime_nsec_2 | |
1111 | * So: | |
1112 | * (offset * adj_1) + xtime_nsec_1 = | |
1113 | * (offset * adj_2) + xtime_nsec_2 | |
1114 | * And we know: | |
1115 | * adj_2 = adj_1 + 1 | |
1116 | * So: | |
1117 | * (offset * adj_1) + xtime_nsec_1 = | |
1118 | * (offset * (adj_1+1)) + xtime_nsec_2 | |
1119 | * (offset * adj_1) + xtime_nsec_1 = | |
1120 | * (offset * adj_1) + offset + xtime_nsec_2 | |
1121 | * Canceling the sides: | |
1122 | * xtime_nsec_1 = offset + xtime_nsec_2 | |
1123 | * Which gives us: | |
1124 | * xtime_nsec_2 = xtime_nsec_1 - offset | |
1125 | * Which simplfies to: | |
1126 | * xtime_nsec -= offset | |
1127 | * | |
1128 | * XXX - TODO: Doc ntp_error calculation. | |
1129 | */ | |
f726a697 JS |
1130 | tk->mult += adj; |
1131 | tk->xtime_interval += interval; | |
1132 | tk->xtime_nsec -= offset; | |
1133 | tk->ntp_error -= (interval - offset) << tk->ntp_error_shift; | |
2a8c0883 | 1134 | |
1d17d174 | 1135 | out_adjust: |
2a8c0883 JS |
1136 | /* |
1137 | * It may be possible that when we entered this function, xtime_nsec | |
1138 | * was very small. Further, if we're slightly speeding the clocksource | |
1139 | * in the code above, its possible the required corrective factor to | |
1140 | * xtime_nsec could cause it to underflow. | |
1141 | * | |
1142 | * Now, since we already accumulated the second, cannot simply roll | |
1143 | * the accumulated second back, since the NTP subsystem has been | |
1144 | * notified via second_overflow. So instead we push xtime_nsec forward | |
1145 | * by the amount we underflowed, and add that amount into the error. | |
1146 | * | |
1147 | * We'll correct this error next time through this function, when | |
1148 | * xtime_nsec is not as small. | |
1149 | */ | |
f726a697 JS |
1150 | if (unlikely((s64)tk->xtime_nsec < 0)) { |
1151 | s64 neg = -(s64)tk->xtime_nsec; | |
1152 | tk->xtime_nsec = 0; | |
1153 | tk->ntp_error += neg << tk->ntp_error_shift; | |
2a8c0883 JS |
1154 | } |
1155 | ||
8524070b JS |
1156 | } |
1157 | ||
1f4f9487 JS |
1158 | /** |
1159 | * accumulate_nsecs_to_secs - Accumulates nsecs into secs | |
1160 | * | |
1161 | * Helper function that accumulates a the nsecs greater then a second | |
1162 | * from the xtime_nsec field to the xtime_secs field. | |
1163 | * It also calls into the NTP code to handle leapsecond processing. | |
1164 | * | |
1165 | */ | |
1166 | static inline void accumulate_nsecs_to_secs(struct timekeeper *tk) | |
1167 | { | |
1168 | u64 nsecps = (u64)NSEC_PER_SEC << tk->shift; | |
1169 | ||
1170 | while (tk->xtime_nsec >= nsecps) { | |
1171 | int leap; | |
1172 | ||
1173 | tk->xtime_nsec -= nsecps; | |
1174 | tk->xtime_sec++; | |
1175 | ||
1176 | /* Figure out if its a leap sec and apply if needed */ | |
1177 | leap = second_overflow(tk->xtime_sec); | |
6d0ef903 JS |
1178 | if (unlikely(leap)) { |
1179 | struct timespec ts; | |
1180 | ||
1181 | tk->xtime_sec += leap; | |
1f4f9487 | 1182 | |
6d0ef903 JS |
1183 | ts.tv_sec = leap; |
1184 | ts.tv_nsec = 0; | |
1185 | tk_set_wall_to_mono(tk, | |
1186 | timespec_sub(tk->wall_to_monotonic, ts)); | |
1187 | ||
cc244dda JS |
1188 | __timekeeping_set_tai_offset(tk, tk->tai_offset - leap); |
1189 | ||
6d0ef903 JS |
1190 | clock_was_set_delayed(); |
1191 | } | |
1f4f9487 JS |
1192 | } |
1193 | } | |
1194 | ||
a092ff0f JS |
1195 | /** |
1196 | * logarithmic_accumulation - shifted accumulation of cycles | |
1197 | * | |
1198 | * This functions accumulates a shifted interval of cycles into | |
1199 | * into a shifted interval nanoseconds. Allows for O(log) accumulation | |
1200 | * loop. | |
1201 | * | |
1202 | * Returns the unconsumed cycles. | |
1203 | */ | |
f726a697 JS |
1204 | static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset, |
1205 | u32 shift) | |
a092ff0f | 1206 | { |
deda2e81 | 1207 | u64 raw_nsecs; |
a092ff0f | 1208 | |
f726a697 JS |
1209 | /* If the offset is smaller then a shifted interval, do nothing */ |
1210 | if (offset < tk->cycle_interval<<shift) | |
a092ff0f JS |
1211 | return offset; |
1212 | ||
1213 | /* Accumulate one shifted interval */ | |
f726a697 JS |
1214 | offset -= tk->cycle_interval << shift; |
1215 | tk->clock->cycle_last += tk->cycle_interval << shift; | |
a092ff0f | 1216 | |
f726a697 JS |
1217 | tk->xtime_nsec += tk->xtime_interval << shift; |
1218 | accumulate_nsecs_to_secs(tk); | |
a092ff0f | 1219 | |
deda2e81 | 1220 | /* Accumulate raw time */ |
5b3900cd | 1221 | raw_nsecs = (u64)tk->raw_interval << shift; |
f726a697 | 1222 | raw_nsecs += tk->raw_time.tv_nsec; |
c7dcf87a JS |
1223 | if (raw_nsecs >= NSEC_PER_SEC) { |
1224 | u64 raw_secs = raw_nsecs; | |
1225 | raw_nsecs = do_div(raw_secs, NSEC_PER_SEC); | |
f726a697 | 1226 | tk->raw_time.tv_sec += raw_secs; |
a092ff0f | 1227 | } |
f726a697 | 1228 | tk->raw_time.tv_nsec = raw_nsecs; |
a092ff0f JS |
1229 | |
1230 | /* Accumulate error between NTP and clock interval */ | |
f726a697 JS |
1231 | tk->ntp_error += ntp_tick_length() << shift; |
1232 | tk->ntp_error -= (tk->xtime_interval + tk->xtime_remainder) << | |
1233 | (tk->ntp_error_shift + shift); | |
a092ff0f JS |
1234 | |
1235 | return offset; | |
1236 | } | |
1237 | ||
92bb1fcf JS |
1238 | #ifdef CONFIG_GENERIC_TIME_VSYSCALL_OLD |
1239 | static inline void old_vsyscall_fixup(struct timekeeper *tk) | |
1240 | { | |
1241 | s64 remainder; | |
1242 | ||
1243 | /* | |
1244 | * Store only full nanoseconds into xtime_nsec after rounding | |
1245 | * it up and add the remainder to the error difference. | |
1246 | * XXX - This is necessary to avoid small 1ns inconsistnecies caused | |
1247 | * by truncating the remainder in vsyscalls. However, it causes | |
1248 | * additional work to be done in timekeeping_adjust(). Once | |
1249 | * the vsyscall implementations are converted to use xtime_nsec | |
1250 | * (shifted nanoseconds), and CONFIG_GENERIC_TIME_VSYSCALL_OLD | |
1251 | * users are removed, this can be killed. | |
1252 | */ | |
1253 | remainder = tk->xtime_nsec & ((1ULL << tk->shift) - 1); | |
1254 | tk->xtime_nsec -= remainder; | |
1255 | tk->xtime_nsec += 1ULL << tk->shift; | |
1256 | tk->ntp_error += remainder << tk->ntp_error_shift; | |
1257 | ||
1258 | } | |
1259 | #else | |
1260 | #define old_vsyscall_fixup(tk) | |
1261 | #endif | |
1262 | ||
1263 | ||
1264 | ||
8524070b JS |
1265 | /** |
1266 | * update_wall_time - Uses the current clocksource to increment the wall time | |
1267 | * | |
8524070b | 1268 | */ |
871cf1e5 | 1269 | static void update_wall_time(void) |
8524070b | 1270 | { |
155ec602 | 1271 | struct clocksource *clock; |
4e250fdd | 1272 | struct timekeeper *tk = &timekeeper; |
8524070b | 1273 | cycle_t offset; |
a092ff0f | 1274 | int shift = 0, maxshift; |
70471f2f JS |
1275 | unsigned long flags; |
1276 | ||
4e250fdd | 1277 | write_seqlock_irqsave(&tk->lock, flags); |
8524070b JS |
1278 | |
1279 | /* Make sure we're fully resumed: */ | |
1280 | if (unlikely(timekeeping_suspended)) | |
70471f2f | 1281 | goto out; |
8524070b | 1282 | |
4e250fdd | 1283 | clock = tk->clock; |
592913ec JS |
1284 | |
1285 | #ifdef CONFIG_ARCH_USES_GETTIMEOFFSET | |
4e250fdd | 1286 | offset = tk->cycle_interval; |
592913ec JS |
1287 | #else |
1288 | offset = (clock->read(clock) - clock->cycle_last) & clock->mask; | |
8524070b | 1289 | #endif |
8524070b | 1290 | |
bf2ac312 JS |
1291 | /* Check if there's really nothing to do */ |
1292 | if (offset < tk->cycle_interval) | |
1293 | goto out; | |
1294 | ||
a092ff0f JS |
1295 | /* |
1296 | * With NO_HZ we may have to accumulate many cycle_intervals | |
1297 | * (think "ticks") worth of time at once. To do this efficiently, | |
1298 | * we calculate the largest doubling multiple of cycle_intervals | |
88b28adf | 1299 | * that is smaller than the offset. We then accumulate that |
a092ff0f JS |
1300 | * chunk in one go, and then try to consume the next smaller |
1301 | * doubled multiple. | |
8524070b | 1302 | */ |
4e250fdd | 1303 | shift = ilog2(offset) - ilog2(tk->cycle_interval); |
a092ff0f | 1304 | shift = max(0, shift); |
88b28adf | 1305 | /* Bound shift to one less than what overflows tick_length */ |
ea7cf49a | 1306 | maxshift = (64 - (ilog2(ntp_tick_length())+1)) - 1; |
a092ff0f | 1307 | shift = min(shift, maxshift); |
4e250fdd JS |
1308 | while (offset >= tk->cycle_interval) { |
1309 | offset = logarithmic_accumulation(tk, offset, shift); | |
1310 | if (offset < tk->cycle_interval<<shift) | |
830ec045 | 1311 | shift--; |
8524070b JS |
1312 | } |
1313 | ||
1314 | /* correct the clock when NTP error is too big */ | |
4e250fdd | 1315 | timekeeping_adjust(tk, offset); |
8524070b | 1316 | |
6a867a39 | 1317 | /* |
92bb1fcf JS |
1318 | * XXX This can be killed once everyone converts |
1319 | * to the new update_vsyscall. | |
1320 | */ | |
1321 | old_vsyscall_fixup(tk); | |
8524070b | 1322 | |
6a867a39 JS |
1323 | /* |
1324 | * Finally, make sure that after the rounding | |
1e75fa8b | 1325 | * xtime_nsec isn't larger than NSEC_PER_SEC |
6a867a39 | 1326 | */ |
4e250fdd | 1327 | accumulate_nsecs_to_secs(tk); |
83f57a11 | 1328 | |
4e250fdd | 1329 | timekeeping_update(tk, false); |
70471f2f JS |
1330 | |
1331 | out: | |
4e250fdd | 1332 | write_sequnlock_irqrestore(&tk->lock, flags); |
70471f2f | 1333 | |
8524070b | 1334 | } |
7c3f1a57 TJ |
1335 | |
1336 | /** | |
1337 | * getboottime - Return the real time of system boot. | |
1338 | * @ts: pointer to the timespec to be set | |
1339 | * | |
abb3a4ea | 1340 | * Returns the wall-time of boot in a timespec. |
7c3f1a57 TJ |
1341 | * |
1342 | * This is based on the wall_to_monotonic offset and the total suspend | |
1343 | * time. Calls to settimeofday will affect the value returned (which | |
1344 | * basically means that however wrong your real time clock is at boot time, | |
1345 | * you get the right time here). | |
1346 | */ | |
1347 | void getboottime(struct timespec *ts) | |
1348 | { | |
4e250fdd | 1349 | struct timekeeper *tk = &timekeeper; |
36d47481 | 1350 | struct timespec boottime = { |
4e250fdd JS |
1351 | .tv_sec = tk->wall_to_monotonic.tv_sec + |
1352 | tk->total_sleep_time.tv_sec, | |
1353 | .tv_nsec = tk->wall_to_monotonic.tv_nsec + | |
1354 | tk->total_sleep_time.tv_nsec | |
36d47481 | 1355 | }; |
d4f587c6 | 1356 | |
d4f587c6 | 1357 | set_normalized_timespec(ts, -boottime.tv_sec, -boottime.tv_nsec); |
7c3f1a57 | 1358 | } |
c93d89f3 | 1359 | EXPORT_SYMBOL_GPL(getboottime); |
7c3f1a57 | 1360 | |
abb3a4ea JS |
1361 | /** |
1362 | * get_monotonic_boottime - Returns monotonic time since boot | |
1363 | * @ts: pointer to the timespec to be set | |
1364 | * | |
1365 | * Returns the monotonic time since boot in a timespec. | |
1366 | * | |
1367 | * This is similar to CLOCK_MONTONIC/ktime_get_ts, but also | |
1368 | * includes the time spent in suspend. | |
1369 | */ | |
1370 | void get_monotonic_boottime(struct timespec *ts) | |
1371 | { | |
4e250fdd | 1372 | struct timekeeper *tk = &timekeeper; |
abb3a4ea | 1373 | struct timespec tomono, sleep; |
ec145bab | 1374 | s64 nsec; |
abb3a4ea | 1375 | unsigned int seq; |
abb3a4ea JS |
1376 | |
1377 | WARN_ON(timekeeping_suspended); | |
1378 | ||
1379 | do { | |
4e250fdd JS |
1380 | seq = read_seqbegin(&tk->lock); |
1381 | ts->tv_sec = tk->xtime_sec; | |
ec145bab | 1382 | nsec = timekeeping_get_ns(tk); |
4e250fdd JS |
1383 | tomono = tk->wall_to_monotonic; |
1384 | sleep = tk->total_sleep_time; | |
abb3a4ea | 1385 | |
4e250fdd | 1386 | } while (read_seqretry(&tk->lock, seq)); |
abb3a4ea | 1387 | |
ec145bab JS |
1388 | ts->tv_sec += tomono.tv_sec + sleep.tv_sec; |
1389 | ts->tv_nsec = 0; | |
1390 | timespec_add_ns(ts, nsec + tomono.tv_nsec + sleep.tv_nsec); | |
abb3a4ea JS |
1391 | } |
1392 | EXPORT_SYMBOL_GPL(get_monotonic_boottime); | |
1393 | ||
1394 | /** | |
1395 | * ktime_get_boottime - Returns monotonic time since boot in a ktime | |
1396 | * | |
1397 | * Returns the monotonic time since boot in a ktime | |
1398 | * | |
1399 | * This is similar to CLOCK_MONTONIC/ktime_get, but also | |
1400 | * includes the time spent in suspend. | |
1401 | */ | |
1402 | ktime_t ktime_get_boottime(void) | |
1403 | { | |
1404 | struct timespec ts; | |
1405 | ||
1406 | get_monotonic_boottime(&ts); | |
1407 | return timespec_to_ktime(ts); | |
1408 | } | |
1409 | EXPORT_SYMBOL_GPL(ktime_get_boottime); | |
1410 | ||
7c3f1a57 TJ |
1411 | /** |
1412 | * monotonic_to_bootbased - Convert the monotonic time to boot based. | |
1413 | * @ts: pointer to the timespec to be converted | |
1414 | */ | |
1415 | void monotonic_to_bootbased(struct timespec *ts) | |
1416 | { | |
4e250fdd JS |
1417 | struct timekeeper *tk = &timekeeper; |
1418 | ||
1419 | *ts = timespec_add(*ts, tk->total_sleep_time); | |
7c3f1a57 | 1420 | } |
c93d89f3 | 1421 | EXPORT_SYMBOL_GPL(monotonic_to_bootbased); |
2c6b47de | 1422 | |
17c38b74 JS |
1423 | unsigned long get_seconds(void) |
1424 | { | |
4e250fdd JS |
1425 | struct timekeeper *tk = &timekeeper; |
1426 | ||
1427 | return tk->xtime_sec; | |
17c38b74 JS |
1428 | } |
1429 | EXPORT_SYMBOL(get_seconds); | |
1430 | ||
da15cfda JS |
1431 | struct timespec __current_kernel_time(void) |
1432 | { | |
4e250fdd JS |
1433 | struct timekeeper *tk = &timekeeper; |
1434 | ||
1435 | return tk_xtime(tk); | |
da15cfda | 1436 | } |
17c38b74 | 1437 | |
2c6b47de JS |
1438 | struct timespec current_kernel_time(void) |
1439 | { | |
4e250fdd | 1440 | struct timekeeper *tk = &timekeeper; |
2c6b47de JS |
1441 | struct timespec now; |
1442 | unsigned long seq; | |
1443 | ||
1444 | do { | |
4e250fdd | 1445 | seq = read_seqbegin(&tk->lock); |
83f57a11 | 1446 | |
4e250fdd JS |
1447 | now = tk_xtime(tk); |
1448 | } while (read_seqretry(&tk->lock, seq)); | |
2c6b47de JS |
1449 | |
1450 | return now; | |
1451 | } | |
2c6b47de | 1452 | EXPORT_SYMBOL(current_kernel_time); |
da15cfda JS |
1453 | |
1454 | struct timespec get_monotonic_coarse(void) | |
1455 | { | |
4e250fdd | 1456 | struct timekeeper *tk = &timekeeper; |
da15cfda JS |
1457 | struct timespec now, mono; |
1458 | unsigned long seq; | |
1459 | ||
1460 | do { | |
4e250fdd | 1461 | seq = read_seqbegin(&tk->lock); |
83f57a11 | 1462 | |
4e250fdd JS |
1463 | now = tk_xtime(tk); |
1464 | mono = tk->wall_to_monotonic; | |
1465 | } while (read_seqretry(&tk->lock, seq)); | |
da15cfda JS |
1466 | |
1467 | set_normalized_timespec(&now, now.tv_sec + mono.tv_sec, | |
1468 | now.tv_nsec + mono.tv_nsec); | |
1469 | return now; | |
1470 | } | |
871cf1e5 TH |
1471 | |
1472 | /* | |
d6ad4187 | 1473 | * Must hold jiffies_lock |
871cf1e5 TH |
1474 | */ |
1475 | void do_timer(unsigned long ticks) | |
1476 | { | |
1477 | jiffies_64 += ticks; | |
1478 | update_wall_time(); | |
1479 | calc_global_load(ticks); | |
1480 | } | |
48cf76f7 TH |
1481 | |
1482 | /** | |
314ac371 JS |
1483 | * get_xtime_and_monotonic_and_sleep_offset() - get xtime, wall_to_monotonic, |
1484 | * and sleep offsets. | |
48cf76f7 TH |
1485 | * @xtim: pointer to timespec to be set with xtime |
1486 | * @wtom: pointer to timespec to be set with wall_to_monotonic | |
314ac371 | 1487 | * @sleep: pointer to timespec to be set with time in suspend |
48cf76f7 | 1488 | */ |
314ac371 JS |
1489 | void get_xtime_and_monotonic_and_sleep_offset(struct timespec *xtim, |
1490 | struct timespec *wtom, struct timespec *sleep) | |
48cf76f7 | 1491 | { |
4e250fdd | 1492 | struct timekeeper *tk = &timekeeper; |
48cf76f7 TH |
1493 | unsigned long seq; |
1494 | ||
1495 | do { | |
4e250fdd JS |
1496 | seq = read_seqbegin(&tk->lock); |
1497 | *xtim = tk_xtime(tk); | |
1498 | *wtom = tk->wall_to_monotonic; | |
1499 | *sleep = tk->total_sleep_time; | |
1500 | } while (read_seqretry(&tk->lock, seq)); | |
48cf76f7 | 1501 | } |
f0af911a | 1502 | |
f6c06abf TG |
1503 | #ifdef CONFIG_HIGH_RES_TIMERS |
1504 | /** | |
1505 | * ktime_get_update_offsets - hrtimer helper | |
1506 | * @offs_real: pointer to storage for monotonic -> realtime offset | |
1507 | * @offs_boot: pointer to storage for monotonic -> boottime offset | |
1508 | * | |
1509 | * Returns current monotonic time and updates the offsets | |
1510 | * Called from hrtimer_interupt() or retrigger_next_event() | |
1511 | */ | |
1512 | ktime_t ktime_get_update_offsets(ktime_t *offs_real, ktime_t *offs_boot) | |
1513 | { | |
4e250fdd | 1514 | struct timekeeper *tk = &timekeeper; |
f6c06abf TG |
1515 | ktime_t now; |
1516 | unsigned int seq; | |
1517 | u64 secs, nsecs; | |
1518 | ||
1519 | do { | |
4e250fdd | 1520 | seq = read_seqbegin(&tk->lock); |
f6c06abf | 1521 | |
4e250fdd JS |
1522 | secs = tk->xtime_sec; |
1523 | nsecs = timekeeping_get_ns(tk); | |
f6c06abf | 1524 | |
4e250fdd JS |
1525 | *offs_real = tk->offs_real; |
1526 | *offs_boot = tk->offs_boot; | |
1527 | } while (read_seqretry(&tk->lock, seq)); | |
f6c06abf TG |
1528 | |
1529 | now = ktime_add_ns(ktime_set(secs, 0), nsecs); | |
1530 | now = ktime_sub(now, *offs_real); | |
1531 | return now; | |
1532 | } | |
1533 | #endif | |
1534 | ||
99ee5315 TG |
1535 | /** |
1536 | * ktime_get_monotonic_offset() - get wall_to_monotonic in ktime_t format | |
1537 | */ | |
1538 | ktime_t ktime_get_monotonic_offset(void) | |
1539 | { | |
4e250fdd | 1540 | struct timekeeper *tk = &timekeeper; |
99ee5315 TG |
1541 | unsigned long seq; |
1542 | struct timespec wtom; | |
1543 | ||
1544 | do { | |
4e250fdd JS |
1545 | seq = read_seqbegin(&tk->lock); |
1546 | wtom = tk->wall_to_monotonic; | |
1547 | } while (read_seqretry(&tk->lock, seq)); | |
70471f2f | 1548 | |
99ee5315 TG |
1549 | return timespec_to_ktime(wtom); |
1550 | } | |
a80b83b7 JS |
1551 | EXPORT_SYMBOL_GPL(ktime_get_monotonic_offset); |
1552 | ||
f0af911a TH |
1553 | /** |
1554 | * xtime_update() - advances the timekeeping infrastructure | |
1555 | * @ticks: number of ticks, that have elapsed since the last call. | |
1556 | * | |
1557 | * Must be called with interrupts disabled. | |
1558 | */ | |
1559 | void xtime_update(unsigned long ticks) | |
1560 | { | |
d6ad4187 | 1561 | write_seqlock(&jiffies_lock); |
f0af911a | 1562 | do_timer(ticks); |
d6ad4187 | 1563 | write_sequnlock(&jiffies_lock); |
f0af911a | 1564 | } |