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Commit | Line | Data |
---|---|---|
4c7ee8de | 1 | /* |
4c7ee8de JS |
2 | * NTP state machine interfaces and logic. |
3 | * | |
4 | * This code was mainly moved from kernel/timer.c and kernel/time.c | |
5 | * Please see those files for relevant copyright info and historical | |
6 | * changelogs. | |
7 | */ | |
aa0ac365 | 8 | #include <linux/capability.h> |
7dffa3c6 | 9 | #include <linux/clocksource.h> |
eb3f938f | 10 | #include <linux/workqueue.h> |
53bbfa9e IM |
11 | #include <linux/hrtimer.h> |
12 | #include <linux/jiffies.h> | |
13 | #include <linux/math64.h> | |
14 | #include <linux/timex.h> | |
15 | #include <linux/time.h> | |
16 | #include <linux/mm.h> | |
4c7ee8de | 17 | |
b0ee7556 | 18 | /* |
53bbfa9e | 19 | * NTP timekeeping variables: |
b0ee7556 | 20 | */ |
b0ee7556 | 21 | |
53bbfa9e IM |
22 | /* USER_HZ period (usecs): */ |
23 | unsigned long tick_usec = TICK_USEC; | |
24 | ||
25 | /* ACTHZ period (nsecs): */ | |
26 | unsigned long tick_nsec; | |
7dffa3c6 | 27 | |
53bbfa9e IM |
28 | u64 tick_length; |
29 | static u64 tick_length_base; | |
30 | ||
31 | static struct hrtimer leap_timer; | |
32 | ||
bbd12676 | 33 | #define MAX_TICKADJ 500LL /* usecs */ |
53bbfa9e | 34 | #define MAX_TICKADJ_SCALED \ |
bbd12676 | 35 | (((MAX_TICKADJ * NSEC_PER_USEC) << NTP_SCALE_SHIFT) / NTP_INTERVAL_FREQ) |
4c7ee8de JS |
36 | |
37 | /* | |
38 | * phase-lock loop variables | |
39 | */ | |
53bbfa9e IM |
40 | |
41 | /* | |
42 | * clock synchronization status | |
43 | * | |
44 | * (TIME_ERROR prevents overwriting the CMOS clock) | |
45 | */ | |
46 | static int time_state = TIME_OK; | |
47 | ||
48 | /* clock status bits: */ | |
49 | int time_status = STA_UNSYNC; | |
50 | ||
51 | /* TAI offset (secs): */ | |
52 | static long time_tai; | |
53 | ||
54 | /* time adjustment (nsecs): */ | |
55 | static s64 time_offset; | |
56 | ||
57 | /* pll time constant: */ | |
58 | static long time_constant = 2; | |
59 | ||
60 | /* maximum error (usecs): */ | |
61 | long time_maxerror = NTP_PHASE_LIMIT; | |
62 | ||
63 | /* estimated error (usecs): */ | |
64 | long time_esterror = NTP_PHASE_LIMIT; | |
65 | ||
66 | /* frequency offset (scaled nsecs/secs): */ | |
67 | static s64 time_freq; | |
68 | ||
69 | /* time at last adjustment (secs): */ | |
70 | static long time_reftime; | |
71 | ||
72 | long time_adjust; | |
73 | ||
74 | static long ntp_tick_adj; | |
75 | ||
76 | /* | |
77 | * NTP methods: | |
78 | */ | |
4c7ee8de | 79 | |
9ce616aa IM |
80 | /* |
81 | * Update (tick_length, tick_length_base, tick_nsec), based | |
82 | * on (tick_usec, ntp_tick_adj, time_freq): | |
83 | */ | |
70bc42f9 AB |
84 | static void ntp_update_frequency(void) |
85 | { | |
9ce616aa | 86 | u64 second_length; |
bc26c31d | 87 | u64 new_base; |
9ce616aa IM |
88 | |
89 | second_length = (u64)(tick_usec * NSEC_PER_USEC * USER_HZ) | |
90 | << NTP_SCALE_SHIFT; | |
91 | ||
92 | second_length += (s64)ntp_tick_adj << NTP_SCALE_SHIFT; | |
93 | second_length += time_freq; | |
70bc42f9 | 94 | |
9ce616aa | 95 | tick_nsec = div_u64(second_length, HZ) >> NTP_SCALE_SHIFT; |
bc26c31d | 96 | new_base = div_u64(second_length, NTP_INTERVAL_FREQ); |
fdcedf7b JS |
97 | |
98 | /* | |
99 | * Don't wait for the next second_overflow, apply | |
bc26c31d | 100 | * the change to the tick length immediately: |
fdcedf7b | 101 | */ |
bc26c31d IM |
102 | tick_length += new_base - tick_length_base; |
103 | tick_length_base = new_base; | |
70bc42f9 AB |
104 | } |
105 | ||
478b7aab | 106 | static inline s64 ntp_update_offset_fll(s64 offset64, long secs) |
f939890b IM |
107 | { |
108 | time_status &= ~STA_MODE; | |
109 | ||
110 | if (secs < MINSEC) | |
478b7aab | 111 | return 0; |
f939890b IM |
112 | |
113 | if (!(time_status & STA_FLL) && (secs <= MAXSEC)) | |
478b7aab | 114 | return 0; |
f939890b | 115 | |
f939890b IM |
116 | time_status |= STA_MODE; |
117 | ||
478b7aab | 118 | return div_s64(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs); |
f939890b IM |
119 | } |
120 | ||
ee9851b2 RZ |
121 | static void ntp_update_offset(long offset) |
122 | { | |
ee9851b2 | 123 | s64 freq_adj; |
f939890b IM |
124 | s64 offset64; |
125 | long secs; | |
ee9851b2 RZ |
126 | |
127 | if (!(time_status & STA_PLL)) | |
128 | return; | |
129 | ||
eea83d89 | 130 | if (!(time_status & STA_NANO)) |
9f14f669 | 131 | offset *= NSEC_PER_USEC; |
ee9851b2 RZ |
132 | |
133 | /* | |
134 | * Scale the phase adjustment and | |
135 | * clamp to the operating range. | |
136 | */ | |
9f14f669 RZ |
137 | offset = min(offset, MAXPHASE); |
138 | offset = max(offset, -MAXPHASE); | |
ee9851b2 RZ |
139 | |
140 | /* | |
141 | * Select how the frequency is to be controlled | |
142 | * and in which mode (PLL or FLL). | |
143 | */ | |
f939890b | 144 | secs = xtime.tv_sec - time_reftime; |
10dd31a7 | 145 | if (unlikely(time_status & STA_FREQHOLD)) |
c7986acb IM |
146 | secs = 0; |
147 | ||
ee9851b2 RZ |
148 | time_reftime = xtime.tv_sec; |
149 | ||
f939890b IM |
150 | offset64 = offset; |
151 | freq_adj = (offset64 * secs) << | |
152 | (NTP_SCALE_SHIFT - 2 * (SHIFT_PLL + 2 + time_constant)); | |
153 | ||
478b7aab | 154 | freq_adj += ntp_update_offset_fll(offset64, secs); |
f939890b IM |
155 | |
156 | freq_adj = min(freq_adj + time_freq, MAXFREQ_SCALED); | |
157 | ||
158 | time_freq = max(freq_adj, -MAXFREQ_SCALED); | |
159 | ||
160 | time_offset = div_s64(offset64 << NTP_SCALE_SHIFT, NTP_INTERVAL_FREQ); | |
ee9851b2 RZ |
161 | } |
162 | ||
b0ee7556 RZ |
163 | /** |
164 | * ntp_clear - Clears the NTP state variables | |
165 | * | |
166 | * Must be called while holding a write on the xtime_lock | |
167 | */ | |
168 | void ntp_clear(void) | |
169 | { | |
53bbfa9e IM |
170 | time_adjust = 0; /* stop active adjtime() */ |
171 | time_status |= STA_UNSYNC; | |
172 | time_maxerror = NTP_PHASE_LIMIT; | |
173 | time_esterror = NTP_PHASE_LIMIT; | |
b0ee7556 RZ |
174 | |
175 | ntp_update_frequency(); | |
176 | ||
53bbfa9e IM |
177 | tick_length = tick_length_base; |
178 | time_offset = 0; | |
b0ee7556 RZ |
179 | } |
180 | ||
4c7ee8de | 181 | /* |
7dffa3c6 RZ |
182 | * Leap second processing. If in leap-insert state at the end of the |
183 | * day, the system clock is set back one second; if in leap-delete | |
184 | * state, the system clock is set ahead one second. | |
4c7ee8de | 185 | */ |
7dffa3c6 | 186 | static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer) |
4c7ee8de | 187 | { |
7dffa3c6 | 188 | enum hrtimer_restart res = HRTIMER_NORESTART; |
4c7ee8de | 189 | |
ca109491 | 190 | write_seqlock(&xtime_lock); |
4c7ee8de | 191 | |
4c7ee8de JS |
192 | switch (time_state) { |
193 | case TIME_OK: | |
4c7ee8de JS |
194 | break; |
195 | case TIME_INS: | |
7dffa3c6 RZ |
196 | xtime.tv_sec--; |
197 | wall_to_monotonic.tv_sec++; | |
198 | time_state = TIME_OOP; | |
53bbfa9e IM |
199 | printk(KERN_NOTICE |
200 | "Clock: inserting leap second 23:59:60 UTC\n"); | |
cc584b21 | 201 | hrtimer_add_expires_ns(&leap_timer, NSEC_PER_SEC); |
7dffa3c6 | 202 | res = HRTIMER_RESTART; |
4c7ee8de JS |
203 | break; |
204 | case TIME_DEL: | |
7dffa3c6 RZ |
205 | xtime.tv_sec++; |
206 | time_tai--; | |
207 | wall_to_monotonic.tv_sec--; | |
208 | time_state = TIME_WAIT; | |
53bbfa9e IM |
209 | printk(KERN_NOTICE |
210 | "Clock: deleting leap second 23:59:59 UTC\n"); | |
4c7ee8de JS |
211 | break; |
212 | case TIME_OOP: | |
153b5d05 | 213 | time_tai++; |
4c7ee8de | 214 | time_state = TIME_WAIT; |
7dffa3c6 | 215 | /* fall through */ |
4c7ee8de JS |
216 | case TIME_WAIT: |
217 | if (!(time_status & (STA_INS | STA_DEL))) | |
ee9851b2 | 218 | time_state = TIME_OK; |
7dffa3c6 RZ |
219 | break; |
220 | } | |
221 | update_vsyscall(&xtime, clock); | |
222 | ||
ca109491 | 223 | write_sequnlock(&xtime_lock); |
7dffa3c6 RZ |
224 | |
225 | return res; | |
226 | } | |
227 | ||
228 | /* | |
229 | * this routine handles the overflow of the microsecond field | |
230 | * | |
231 | * The tricky bits of code to handle the accurate clock support | |
232 | * were provided by Dave Mills (Mills@UDEL.EDU) of NTP fame. | |
233 | * They were originally developed for SUN and DEC kernels. | |
234 | * All the kudos should go to Dave for this stuff. | |
235 | */ | |
236 | void second_overflow(void) | |
237 | { | |
238 | s64 time_adj; | |
239 | ||
240 | /* Bump the maxerror field */ | |
241 | time_maxerror += MAXFREQ / NSEC_PER_USEC; | |
242 | if (time_maxerror > NTP_PHASE_LIMIT) { | |
243 | time_maxerror = NTP_PHASE_LIMIT; | |
244 | time_status |= STA_UNSYNC; | |
4c7ee8de JS |
245 | } |
246 | ||
247 | /* | |
f1992393 RZ |
248 | * Compute the phase adjustment for the next second. The offset is |
249 | * reduced by a fixed factor times the time constant. | |
4c7ee8de | 250 | */ |
53bbfa9e IM |
251 | tick_length = tick_length_base; |
252 | time_adj = shift_right(time_offset, SHIFT_PLL + time_constant); | |
253 | time_offset -= time_adj; | |
254 | tick_length += time_adj; | |
4c7ee8de | 255 | |
3c972c24 IM |
256 | if (!time_adjust) |
257 | return; | |
258 | ||
259 | if (time_adjust > MAX_TICKADJ) { | |
260 | time_adjust -= MAX_TICKADJ; | |
261 | tick_length += MAX_TICKADJ_SCALED; | |
262 | return; | |
4c7ee8de | 263 | } |
3c972c24 IM |
264 | |
265 | if (time_adjust < -MAX_TICKADJ) { | |
266 | time_adjust += MAX_TICKADJ; | |
267 | tick_length -= MAX_TICKADJ_SCALED; | |
268 | return; | |
269 | } | |
270 | ||
271 | tick_length += (s64)(time_adjust * NSEC_PER_USEC / NTP_INTERVAL_FREQ) | |
272 | << NTP_SCALE_SHIFT; | |
273 | time_adjust = 0; | |
4c7ee8de JS |
274 | } |
275 | ||
82644459 | 276 | #ifdef CONFIG_GENERIC_CMOS_UPDATE |
4c7ee8de | 277 | |
82644459 TG |
278 | /* Disable the cmos update - used by virtualization and embedded */ |
279 | int no_sync_cmos_clock __read_mostly; | |
280 | ||
eb3f938f | 281 | static void sync_cmos_clock(struct work_struct *work); |
82644459 | 282 | |
eb3f938f | 283 | static DECLARE_DELAYED_WORK(sync_cmos_work, sync_cmos_clock); |
82644459 | 284 | |
eb3f938f | 285 | static void sync_cmos_clock(struct work_struct *work) |
82644459 TG |
286 | { |
287 | struct timespec now, next; | |
288 | int fail = 1; | |
289 | ||
290 | /* | |
291 | * If we have an externally synchronized Linux clock, then update | |
292 | * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be | |
293 | * called as close as possible to 500 ms before the new second starts. | |
294 | * This code is run on a timer. If the clock is set, that timer | |
295 | * may not expire at the correct time. Thus, we adjust... | |
296 | */ | |
53bbfa9e | 297 | if (!ntp_synced()) { |
82644459 TG |
298 | /* |
299 | * Not synced, exit, do not restart a timer (if one is | |
300 | * running, let it run out). | |
301 | */ | |
302 | return; | |
53bbfa9e | 303 | } |
82644459 TG |
304 | |
305 | getnstimeofday(&now); | |
fa6a1a55 | 306 | if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) |
82644459 TG |
307 | fail = update_persistent_clock(now); |
308 | ||
4ff4b9e1 | 309 | next.tv_nsec = (NSEC_PER_SEC / 2) - now.tv_nsec - (TICK_NSEC / 2); |
82644459 TG |
310 | if (next.tv_nsec <= 0) |
311 | next.tv_nsec += NSEC_PER_SEC; | |
312 | ||
313 | if (!fail) | |
314 | next.tv_sec = 659; | |
315 | else | |
316 | next.tv_sec = 0; | |
317 | ||
318 | if (next.tv_nsec >= NSEC_PER_SEC) { | |
319 | next.tv_sec++; | |
320 | next.tv_nsec -= NSEC_PER_SEC; | |
321 | } | |
eb3f938f | 322 | schedule_delayed_work(&sync_cmos_work, timespec_to_jiffies(&next)); |
82644459 TG |
323 | } |
324 | ||
325 | static void notify_cmos_timer(void) | |
4c7ee8de | 326 | { |
298a5df4 | 327 | if (!no_sync_cmos_clock) |
eb3f938f | 328 | schedule_delayed_work(&sync_cmos_work, 0); |
4c7ee8de JS |
329 | } |
330 | ||
82644459 TG |
331 | #else |
332 | static inline void notify_cmos_timer(void) { } | |
333 | #endif | |
334 | ||
80f22571 IM |
335 | |
336 | /* | |
337 | * Propagate a new txc->status value into the NTP state: | |
338 | */ | |
339 | static inline void process_adj_status(struct timex *txc, struct timespec *ts) | |
340 | { | |
341 | long now; | |
342 | ||
343 | if ((time_status & STA_PLL) && !(txc->status & STA_PLL)) { | |
344 | time_state = TIME_OK; | |
345 | time_status = STA_UNSYNC; | |
346 | } | |
347 | /* only set allowed bits */ | |
348 | time_status &= STA_RONLY; | |
349 | ||
350 | /* | |
351 | * If we turn on PLL adjustments then reset the | |
352 | * reference time to current time. | |
353 | */ | |
354 | if (!(time_status & STA_PLL) && (txc->status & STA_PLL)) | |
355 | time_reftime = xtime.tv_sec; | |
356 | ||
357 | time_status |= txc->status & ~STA_RONLY; | |
358 | ||
359 | switch (time_state) { | |
360 | case TIME_OK: | |
361 | start_timer: | |
362 | now = ts->tv_sec; | |
363 | if (time_status & STA_INS) { | |
364 | time_state = TIME_INS; | |
365 | now += 86400 - now % 86400; | |
366 | hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS); | |
367 | } else if (time_status & STA_DEL) { | |
368 | time_state = TIME_DEL; | |
369 | now += 86400 - (now + 1) % 86400; | |
370 | hrtimer_start(&leap_timer, ktime_set(now, 0), HRTIMER_MODE_ABS); | |
371 | } | |
372 | break; | |
373 | case TIME_INS: | |
374 | case TIME_DEL: | |
375 | time_state = TIME_OK; | |
376 | goto start_timer; | |
377 | case TIME_WAIT: | |
378 | if (!(time_status & (STA_INS | STA_DEL))) | |
379 | time_state = TIME_OK; | |
380 | break; | |
381 | case TIME_OOP: | |
382 | hrtimer_restart(&leap_timer); | |
383 | break; | |
384 | } | |
385 | } | |
386 | /* | |
387 | * Called with the xtime lock held, so we can access and modify | |
388 | * all the global NTP state: | |
389 | */ | |
390 | static inline void process_adjtimex_modes(struct timex *txc, struct timespec *ts) | |
391 | { | |
392 | if (txc->modes & ADJ_STATUS) | |
393 | process_adj_status(txc, ts); | |
394 | ||
395 | if (txc->modes & ADJ_NANO) | |
396 | time_status |= STA_NANO; | |
397 | if (txc->modes & ADJ_MICRO) | |
398 | time_status &= ~STA_NANO; | |
399 | ||
400 | if (txc->modes & ADJ_FREQUENCY) { | |
401 | time_freq = (s64)txc->freq * PPM_SCALE; | |
402 | time_freq = min(time_freq, MAXFREQ_SCALED); | |
403 | time_freq = max(time_freq, -MAXFREQ_SCALED); | |
404 | } | |
405 | ||
406 | if (txc->modes & ADJ_MAXERROR) | |
407 | time_maxerror = txc->maxerror; | |
408 | if (txc->modes & ADJ_ESTERROR) | |
409 | time_esterror = txc->esterror; | |
410 | ||
411 | if (txc->modes & ADJ_TIMECONST) { | |
412 | time_constant = txc->constant; | |
413 | if (!(time_status & STA_NANO)) | |
414 | time_constant += 4; | |
415 | time_constant = min(time_constant, (long)MAXTC); | |
416 | time_constant = max(time_constant, 0l); | |
417 | } | |
418 | ||
419 | if (txc->modes & ADJ_TAI && txc->constant > 0) | |
420 | time_tai = txc->constant; | |
421 | ||
422 | if (txc->modes & ADJ_OFFSET) | |
423 | ntp_update_offset(txc->offset); | |
424 | if (txc->modes & ADJ_TICK) | |
425 | tick_usec = txc->tick; | |
426 | ||
427 | if (txc->modes & (ADJ_TICK|ADJ_FREQUENCY|ADJ_OFFSET)) | |
428 | ntp_update_frequency(); | |
429 | } | |
430 | ||
53bbfa9e IM |
431 | /* |
432 | * adjtimex mainly allows reading (and writing, if superuser) of | |
4c7ee8de JS |
433 | * kernel time-keeping variables. used by xntpd. |
434 | */ | |
435 | int do_adjtimex(struct timex *txc) | |
436 | { | |
eea83d89 | 437 | struct timespec ts; |
4c7ee8de JS |
438 | int result; |
439 | ||
916c7a85 RZ |
440 | /* Validate the data before disabling interrupts */ |
441 | if (txc->modes & ADJ_ADJTIME) { | |
eea83d89 | 442 | /* singleshot must not be used with any other mode bits */ |
916c7a85 | 443 | if (!(txc->modes & ADJ_OFFSET_SINGLESHOT)) |
4c7ee8de | 444 | return -EINVAL; |
916c7a85 RZ |
445 | if (!(txc->modes & ADJ_OFFSET_READONLY) && |
446 | !capable(CAP_SYS_TIME)) | |
447 | return -EPERM; | |
448 | } else { | |
449 | /* In order to modify anything, you gotta be super-user! */ | |
450 | if (txc->modes && !capable(CAP_SYS_TIME)) | |
451 | return -EPERM; | |
452 | ||
53bbfa9e IM |
453 | /* |
454 | * if the quartz is off by more than 10% then | |
455 | * something is VERY wrong! | |
456 | */ | |
916c7a85 RZ |
457 | if (txc->modes & ADJ_TICK && |
458 | (txc->tick < 900000/USER_HZ || | |
459 | txc->tick > 1100000/USER_HZ)) | |
460 | return -EINVAL; | |
461 | ||
462 | if (txc->modes & ADJ_STATUS && time_state != TIME_OK) | |
463 | hrtimer_cancel(&leap_timer); | |
52bfb360 | 464 | } |
4c7ee8de | 465 | |
7dffa3c6 RZ |
466 | getnstimeofday(&ts); |
467 | ||
4c7ee8de | 468 | write_seqlock_irq(&xtime_lock); |
4c7ee8de | 469 | |
4c7ee8de | 470 | /* If there are input parameters, then process them */ |
916c7a85 RZ |
471 | if (txc->modes & ADJ_ADJTIME) { |
472 | long save_adjust = time_adjust; | |
473 | ||
474 | if (!(txc->modes & ADJ_OFFSET_READONLY)) { | |
475 | /* adjtime() is independent from ntp_adjtime() */ | |
476 | time_adjust = txc->offset; | |
477 | ntp_update_frequency(); | |
478 | } | |
479 | txc->offset = save_adjust; | |
480 | goto adj_done; | |
481 | } | |
ee9851b2 | 482 | |
80f22571 IM |
483 | /* If there are input parameters, then process them: */ |
484 | if (txc->modes) | |
485 | process_adjtimex_modes(txc, &ts); | |
eea83d89 | 486 | |
916c7a85 RZ |
487 | txc->offset = shift_right(time_offset * NTP_INTERVAL_FREQ, |
488 | NTP_SCALE_SHIFT); | |
489 | if (!(time_status & STA_NANO)) | |
490 | txc->offset /= NSEC_PER_USEC; | |
491 | ||
492 | adj_done: | |
eea83d89 | 493 | result = time_state; /* mostly `TIME_OK' */ |
ee9851b2 | 494 | if (time_status & (STA_UNSYNC|STA_CLOCKERR)) |
4c7ee8de JS |
495 | result = TIME_ERROR; |
496 | ||
d40e944c RZ |
497 | txc->freq = shift_right((time_freq >> PPM_SCALE_INV_SHIFT) * |
498 | (s64)PPM_SCALE_INV, NTP_SCALE_SHIFT); | |
4c7ee8de JS |
499 | txc->maxerror = time_maxerror; |
500 | txc->esterror = time_esterror; | |
501 | txc->status = time_status; | |
502 | txc->constant = time_constant; | |
70bc42f9 | 503 | txc->precision = 1; |
074b3b87 | 504 | txc->tolerance = MAXFREQ_SCALED / PPM_SCALE; |
4c7ee8de | 505 | txc->tick = tick_usec; |
153b5d05 | 506 | txc->tai = time_tai; |
4c7ee8de JS |
507 | |
508 | /* PPS is not implemented, so these are zero */ | |
509 | txc->ppsfreq = 0; | |
510 | txc->jitter = 0; | |
511 | txc->shift = 0; | |
512 | txc->stabil = 0; | |
513 | txc->jitcnt = 0; | |
514 | txc->calcnt = 0; | |
515 | txc->errcnt = 0; | |
516 | txc->stbcnt = 0; | |
517 | write_sequnlock_irq(&xtime_lock); | |
ee9851b2 | 518 | |
eea83d89 RZ |
519 | txc->time.tv_sec = ts.tv_sec; |
520 | txc->time.tv_usec = ts.tv_nsec; | |
521 | if (!(time_status & STA_NANO)) | |
522 | txc->time.tv_usec /= NSEC_PER_USEC; | |
ee9851b2 | 523 | |
82644459 | 524 | notify_cmos_timer(); |
ee9851b2 RZ |
525 | |
526 | return result; | |
4c7ee8de | 527 | } |
10a398d0 RZ |
528 | |
529 | static int __init ntp_tick_adj_setup(char *str) | |
530 | { | |
531 | ntp_tick_adj = simple_strtol(str, NULL, 0); | |
532 | return 1; | |
533 | } | |
534 | ||
535 | __setup("ntp_tick_adj=", ntp_tick_adj_setup); | |
7dffa3c6 RZ |
536 | |
537 | void __init ntp_init(void) | |
538 | { | |
539 | ntp_clear(); | |
540 | hrtimer_init(&leap_timer, CLOCK_REALTIME, HRTIMER_MODE_ABS); | |
541 | leap_timer.function = ntp_leap_second; | |
542 | } |