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