FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_tc.c
1 /*-
2 * ----------------------------------------------------------------------------
3 * "THE BEER-WARE LICENSE" (Revision 42):
4 * <phk@FreeBSD.ORG> wrote this file. As long as you retain this notice you
5 * can do whatever you want with this stuff. If we meet some day, and you think
6 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
7 * ----------------------------------------------------------------------------
8 *
9 * Copyright (c) 2011 The FreeBSD Foundation
10 * All rights reserved.
11 *
12 * Portions of this software were developed by Julien Ridoux at the University
13 * of Melbourne under sponsorship from the FreeBSD Foundation.
14 */
15
16 #include <sys/cdefs.h>
17 __FBSDID("$FreeBSD: releng/10.2/sys/kern/kern_tc.c 285753 2015-07-21 15:06:22Z kib $");
18
19 #include "opt_compat.h"
20 #include "opt_ntp.h"
21 #include "opt_ffclock.h"
22
23 #include <sys/param.h>
24 #include <sys/kernel.h>
25 #include <sys/limits.h>
26 #include <sys/lock.h>
27 #include <sys/mutex.h>
28 #include <sys/sysctl.h>
29 #include <sys/syslog.h>
30 #include <sys/systm.h>
31 #include <sys/timeffc.h>
32 #include <sys/timepps.h>
33 #include <sys/timetc.h>
34 #include <sys/timex.h>
35 #include <sys/vdso.h>
36
37 /*
38 * A large step happens on boot. This constant detects such steps.
39 * It is relatively small so that ntp_update_second gets called enough
40 * in the typical 'missed a couple of seconds' case, but doesn't loop
41 * forever when the time step is large.
42 */
43 #define LARGE_STEP 200
44
45 /*
46 * Implement a dummy timecounter which we can use until we get a real one
47 * in the air. This allows the console and other early stuff to use
48 * time services.
49 */
50
51 static u_int
52 dummy_get_timecount(struct timecounter *tc)
53 {
54 static u_int now;
55
56 return (++now);
57 }
58
59 static struct timecounter dummy_timecounter = {
60 dummy_get_timecount, 0, ~0u, 1000000, "dummy", -1000000
61 };
62
63 struct timehands {
64 /* These fields must be initialized by the driver. */
65 struct timecounter *th_counter;
66 int64_t th_adjustment;
67 uint64_t th_scale;
68 u_int th_offset_count;
69 struct bintime th_offset;
70 struct timeval th_microtime;
71 struct timespec th_nanotime;
72 /* Fields not to be copied in tc_windup start with th_generation. */
73 volatile u_int th_generation;
74 struct timehands *th_next;
75 };
76
77 static struct timehands th0;
78 static struct timehands th9 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0, &th0};
79 static struct timehands th8 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0, &th9};
80 static struct timehands th7 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0, &th8};
81 static struct timehands th6 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0, &th7};
82 static struct timehands th5 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0, &th6};
83 static struct timehands th4 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0, &th5};
84 static struct timehands th3 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0, &th4};
85 static struct timehands th2 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0, &th3};
86 static struct timehands th1 = { NULL, 0, 0, 0, {0, 0}, {0, 0}, {0, 0}, 0, &th2};
87 static struct timehands th0 = {
88 &dummy_timecounter,
89 0,
90 (uint64_t)-1 / 1000000,
91 0,
92 {1, 0},
93 {0, 0},
94 {0, 0},
95 1,
96 &th1
97 };
98
99 static struct timehands *volatile timehands = &th0;
100 struct timecounter *timecounter = &dummy_timecounter;
101 static struct timecounter *timecounters = &dummy_timecounter;
102
103 int tc_min_ticktock_freq = 1;
104
105 volatile time_t time_second = 1;
106 volatile time_t time_uptime = 1;
107
108 struct bintime boottimebin;
109 struct timeval boottime;
110 static int sysctl_kern_boottime(SYSCTL_HANDLER_ARGS);
111 SYSCTL_PROC(_kern, KERN_BOOTTIME, boottime, CTLTYPE_STRUCT|CTLFLAG_RD,
112 NULL, 0, sysctl_kern_boottime, "S,timeval", "System boottime");
113
114 SYSCTL_NODE(_kern, OID_AUTO, timecounter, CTLFLAG_RW, 0, "");
115 static SYSCTL_NODE(_kern_timecounter, OID_AUTO, tc, CTLFLAG_RW, 0, "");
116
117 static int timestepwarnings;
118 SYSCTL_INT(_kern_timecounter, OID_AUTO, stepwarnings, CTLFLAG_RW,
119 ×tepwarnings, 0, "Log time steps");
120
121 struct bintime bt_timethreshold;
122 struct bintime bt_tickthreshold;
123 sbintime_t sbt_timethreshold;
124 sbintime_t sbt_tickthreshold;
125 struct bintime tc_tick_bt;
126 sbintime_t tc_tick_sbt;
127 int tc_precexp;
128 int tc_timepercentage = TC_DEFAULTPERC;
129 TUNABLE_INT("kern.timecounter.alloweddeviation", &tc_timepercentage);
130 static int sysctl_kern_timecounter_adjprecision(SYSCTL_HANDLER_ARGS);
131 SYSCTL_PROC(_kern_timecounter, OID_AUTO, alloweddeviation,
132 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0,
133 sysctl_kern_timecounter_adjprecision, "I",
134 "Allowed time interval deviation in percents");
135
136 static void tc_windup(void);
137 static void cpu_tick_calibrate(int);
138
139 void dtrace_getnanotime(struct timespec *tsp);
140
141 static int
142 sysctl_kern_boottime(SYSCTL_HANDLER_ARGS)
143 {
144 #ifndef __mips__
145 #ifdef SCTL_MASK32
146 int tv[2];
147
148 if (req->flags & SCTL_MASK32) {
149 tv[0] = boottime.tv_sec;
150 tv[1] = boottime.tv_usec;
151 return SYSCTL_OUT(req, tv, sizeof(tv));
152 } else
153 #endif
154 #endif
155 return SYSCTL_OUT(req, &boottime, sizeof(boottime));
156 }
157
158 static int
159 sysctl_kern_timecounter_get(SYSCTL_HANDLER_ARGS)
160 {
161 u_int ncount;
162 struct timecounter *tc = arg1;
163
164 ncount = tc->tc_get_timecount(tc);
165 return sysctl_handle_int(oidp, &ncount, 0, req);
166 }
167
168 static int
169 sysctl_kern_timecounter_freq(SYSCTL_HANDLER_ARGS)
170 {
171 uint64_t freq;
172 struct timecounter *tc = arg1;
173
174 freq = tc->tc_frequency;
175 return sysctl_handle_64(oidp, &freq, 0, req);
176 }
177
178 /*
179 * Return the difference between the timehands' counter value now and what
180 * was when we copied it to the timehands' offset_count.
181 */
182 static __inline u_int
183 tc_delta(struct timehands *th)
184 {
185 struct timecounter *tc;
186
187 tc = th->th_counter;
188 return ((tc->tc_get_timecount(tc) - th->th_offset_count) &
189 tc->tc_counter_mask);
190 }
191
192 /*
193 * Functions for reading the time. We have to loop until we are sure that
194 * the timehands that we operated on was not updated under our feet. See
195 * the comment in <sys/time.h> for a description of these 12 functions.
196 */
197
198 #ifdef FFCLOCK
199 void
200 fbclock_binuptime(struct bintime *bt)
201 {
202 struct timehands *th;
203 unsigned int gen;
204
205 do {
206 th = timehands;
207 gen = th->th_generation;
208 *bt = th->th_offset;
209 bintime_addx(bt, th->th_scale * tc_delta(th));
210 } while (gen == 0 || gen != th->th_generation);
211 }
212
213 void
214 fbclock_nanouptime(struct timespec *tsp)
215 {
216 struct bintime bt;
217
218 fbclock_binuptime(&bt);
219 bintime2timespec(&bt, tsp);
220 }
221
222 void
223 fbclock_microuptime(struct timeval *tvp)
224 {
225 struct bintime bt;
226
227 fbclock_binuptime(&bt);
228 bintime2timeval(&bt, tvp);
229 }
230
231 void
232 fbclock_bintime(struct bintime *bt)
233 {
234
235 fbclock_binuptime(bt);
236 bintime_add(bt, &boottimebin);
237 }
238
239 void
240 fbclock_nanotime(struct timespec *tsp)
241 {
242 struct bintime bt;
243
244 fbclock_bintime(&bt);
245 bintime2timespec(&bt, tsp);
246 }
247
248 void
249 fbclock_microtime(struct timeval *tvp)
250 {
251 struct bintime bt;
252
253 fbclock_bintime(&bt);
254 bintime2timeval(&bt, tvp);
255 }
256
257 void
258 fbclock_getbinuptime(struct bintime *bt)
259 {
260 struct timehands *th;
261 unsigned int gen;
262
263 do {
264 th = timehands;
265 gen = th->th_generation;
266 *bt = th->th_offset;
267 } while (gen == 0 || gen != th->th_generation);
268 }
269
270 void
271 fbclock_getnanouptime(struct timespec *tsp)
272 {
273 struct timehands *th;
274 unsigned int gen;
275
276 do {
277 th = timehands;
278 gen = th->th_generation;
279 bintime2timespec(&th->th_offset, tsp);
280 } while (gen == 0 || gen != th->th_generation);
281 }
282
283 void
284 fbclock_getmicrouptime(struct timeval *tvp)
285 {
286 struct timehands *th;
287 unsigned int gen;
288
289 do {
290 th = timehands;
291 gen = th->th_generation;
292 bintime2timeval(&th->th_offset, tvp);
293 } while (gen == 0 || gen != th->th_generation);
294 }
295
296 void
297 fbclock_getbintime(struct bintime *bt)
298 {
299 struct timehands *th;
300 unsigned int gen;
301
302 do {
303 th = timehands;
304 gen = th->th_generation;
305 *bt = th->th_offset;
306 } while (gen == 0 || gen != th->th_generation);
307 bintime_add(bt, &boottimebin);
308 }
309
310 void
311 fbclock_getnanotime(struct timespec *tsp)
312 {
313 struct timehands *th;
314 unsigned int gen;
315
316 do {
317 th = timehands;
318 gen = th->th_generation;
319 *tsp = th->th_nanotime;
320 } while (gen == 0 || gen != th->th_generation);
321 }
322
323 void
324 fbclock_getmicrotime(struct timeval *tvp)
325 {
326 struct timehands *th;
327 unsigned int gen;
328
329 do {
330 th = timehands;
331 gen = th->th_generation;
332 *tvp = th->th_microtime;
333 } while (gen == 0 || gen != th->th_generation);
334 }
335 #else /* !FFCLOCK */
336 void
337 binuptime(struct bintime *bt)
338 {
339 struct timehands *th;
340 u_int gen;
341
342 do {
343 th = timehands;
344 gen = th->th_generation;
345 *bt = th->th_offset;
346 bintime_addx(bt, th->th_scale * tc_delta(th));
347 } while (gen == 0 || gen != th->th_generation);
348 }
349
350 void
351 nanouptime(struct timespec *tsp)
352 {
353 struct bintime bt;
354
355 binuptime(&bt);
356 bintime2timespec(&bt, tsp);
357 }
358
359 void
360 microuptime(struct timeval *tvp)
361 {
362 struct bintime bt;
363
364 binuptime(&bt);
365 bintime2timeval(&bt, tvp);
366 }
367
368 void
369 bintime(struct bintime *bt)
370 {
371
372 binuptime(bt);
373 bintime_add(bt, &boottimebin);
374 }
375
376 void
377 nanotime(struct timespec *tsp)
378 {
379 struct bintime bt;
380
381 bintime(&bt);
382 bintime2timespec(&bt, tsp);
383 }
384
385 void
386 microtime(struct timeval *tvp)
387 {
388 struct bintime bt;
389
390 bintime(&bt);
391 bintime2timeval(&bt, tvp);
392 }
393
394 void
395 getbinuptime(struct bintime *bt)
396 {
397 struct timehands *th;
398 u_int gen;
399
400 do {
401 th = timehands;
402 gen = th->th_generation;
403 *bt = th->th_offset;
404 } while (gen == 0 || gen != th->th_generation);
405 }
406
407 void
408 getnanouptime(struct timespec *tsp)
409 {
410 struct timehands *th;
411 u_int gen;
412
413 do {
414 th = timehands;
415 gen = th->th_generation;
416 bintime2timespec(&th->th_offset, tsp);
417 } while (gen == 0 || gen != th->th_generation);
418 }
419
420 void
421 getmicrouptime(struct timeval *tvp)
422 {
423 struct timehands *th;
424 u_int gen;
425
426 do {
427 th = timehands;
428 gen = th->th_generation;
429 bintime2timeval(&th->th_offset, tvp);
430 } while (gen == 0 || gen != th->th_generation);
431 }
432
433 void
434 getbintime(struct bintime *bt)
435 {
436 struct timehands *th;
437 u_int gen;
438
439 do {
440 th = timehands;
441 gen = th->th_generation;
442 *bt = th->th_offset;
443 } while (gen == 0 || gen != th->th_generation);
444 bintime_add(bt, &boottimebin);
445 }
446
447 void
448 getnanotime(struct timespec *tsp)
449 {
450 struct timehands *th;
451 u_int gen;
452
453 do {
454 th = timehands;
455 gen = th->th_generation;
456 *tsp = th->th_nanotime;
457 } while (gen == 0 || gen != th->th_generation);
458 }
459
460 void
461 getmicrotime(struct timeval *tvp)
462 {
463 struct timehands *th;
464 u_int gen;
465
466 do {
467 th = timehands;
468 gen = th->th_generation;
469 *tvp = th->th_microtime;
470 } while (gen == 0 || gen != th->th_generation);
471 }
472 #endif /* FFCLOCK */
473
474 #ifdef FFCLOCK
475 /*
476 * Support for feed-forward synchronization algorithms. This is heavily inspired
477 * by the timehands mechanism but kept independent from it. *_windup() functions
478 * have some connection to avoid accessing the timecounter hardware more than
479 * necessary.
480 */
481
482 /* Feed-forward clock estimates kept updated by the synchronization daemon. */
483 struct ffclock_estimate ffclock_estimate;
484 struct bintime ffclock_boottime; /* Feed-forward boot time estimate. */
485 uint32_t ffclock_status; /* Feed-forward clock status. */
486 int8_t ffclock_updated; /* New estimates are available. */
487 struct mtx ffclock_mtx; /* Mutex on ffclock_estimate. */
488
489 struct fftimehands {
490 struct ffclock_estimate cest;
491 struct bintime tick_time;
492 struct bintime tick_time_lerp;
493 ffcounter tick_ffcount;
494 uint64_t period_lerp;
495 volatile uint8_t gen;
496 struct fftimehands *next;
497 };
498
499 #define NUM_ELEMENTS(x) (sizeof(x) / sizeof(*x))
500
501 static struct fftimehands ffth[10];
502 static struct fftimehands *volatile fftimehands = ffth;
503
504 static void
505 ffclock_init(void)
506 {
507 struct fftimehands *cur;
508 struct fftimehands *last;
509
510 memset(ffth, 0, sizeof(ffth));
511
512 last = ffth + NUM_ELEMENTS(ffth) - 1;
513 for (cur = ffth; cur < last; cur++)
514 cur->next = cur + 1;
515 last->next = ffth;
516
517 ffclock_updated = 0;
518 ffclock_status = FFCLOCK_STA_UNSYNC;
519 mtx_init(&ffclock_mtx, "ffclock lock", NULL, MTX_DEF);
520 }
521
522 /*
523 * Reset the feed-forward clock estimates. Called from inittodr() to get things
524 * kick started and uses the timecounter nominal frequency as a first period
525 * estimate. Note: this function may be called several time just after boot.
526 * Note: this is the only function that sets the value of boot time for the
527 * monotonic (i.e. uptime) version of the feed-forward clock.
528 */
529 void
530 ffclock_reset_clock(struct timespec *ts)
531 {
532 struct timecounter *tc;
533 struct ffclock_estimate cest;
534
535 tc = timehands->th_counter;
536 memset(&cest, 0, sizeof(struct ffclock_estimate));
537
538 timespec2bintime(ts, &ffclock_boottime);
539 timespec2bintime(ts, &(cest.update_time));
540 ffclock_read_counter(&cest.update_ffcount);
541 cest.leapsec_next = 0;
542 cest.period = ((1ULL << 63) / tc->tc_frequency) << 1;
543 cest.errb_abs = 0;
544 cest.errb_rate = 0;
545 cest.status = FFCLOCK_STA_UNSYNC;
546 cest.leapsec_total = 0;
547 cest.leapsec = 0;
548
549 mtx_lock(&ffclock_mtx);
550 bcopy(&cest, &ffclock_estimate, sizeof(struct ffclock_estimate));
551 ffclock_updated = INT8_MAX;
552 mtx_unlock(&ffclock_mtx);
553
554 printf("ffclock reset: %s (%llu Hz), time = %ld.%09lu\n", tc->tc_name,
555 (unsigned long long)tc->tc_frequency, (long)ts->tv_sec,
556 (unsigned long)ts->tv_nsec);
557 }
558
559 /*
560 * Sub-routine to convert a time interval measured in RAW counter units to time
561 * in seconds stored in bintime format.
562 * NOTE: bintime_mul requires u_int, but the value of the ffcounter may be
563 * larger than the max value of u_int (on 32 bit architecture). Loop to consume
564 * extra cycles.
565 */
566 static void
567 ffclock_convert_delta(ffcounter ffdelta, uint64_t period, struct bintime *bt)
568 {
569 struct bintime bt2;
570 ffcounter delta, delta_max;
571
572 delta_max = (1ULL << (8 * sizeof(unsigned int))) - 1;
573 bintime_clear(bt);
574 do {
575 if (ffdelta > delta_max)
576 delta = delta_max;
577 else
578 delta = ffdelta;
579 bt2.sec = 0;
580 bt2.frac = period;
581 bintime_mul(&bt2, (unsigned int)delta);
582 bintime_add(bt, &bt2);
583 ffdelta -= delta;
584 } while (ffdelta > 0);
585 }
586
587 /*
588 * Update the fftimehands.
589 * Push the tick ffcount and time(s) forward based on current clock estimate.
590 * The conversion from ffcounter to bintime relies on the difference clock
591 * principle, whose accuracy relies on computing small time intervals. If a new
592 * clock estimate has been passed by the synchronisation daemon, make it
593 * current, and compute the linear interpolation for monotonic time if needed.
594 */
595 static void
596 ffclock_windup(unsigned int delta)
597 {
598 struct ffclock_estimate *cest;
599 struct fftimehands *ffth;
600 struct bintime bt, gap_lerp;
601 ffcounter ffdelta;
602 uint64_t frac;
603 unsigned int polling;
604 uint8_t forward_jump, ogen;
605
606 /*
607 * Pick the next timehand, copy current ffclock estimates and move tick
608 * times and counter forward.
609 */
610 forward_jump = 0;
611 ffth = fftimehands->next;
612 ogen = ffth->gen;
613 ffth->gen = 0;
614 cest = &ffth->cest;
615 bcopy(&fftimehands->cest, cest, sizeof(struct ffclock_estimate));
616 ffdelta = (ffcounter)delta;
617 ffth->period_lerp = fftimehands->period_lerp;
618
619 ffth->tick_time = fftimehands->tick_time;
620 ffclock_convert_delta(ffdelta, cest->period, &bt);
621 bintime_add(&ffth->tick_time, &bt);
622
623 ffth->tick_time_lerp = fftimehands->tick_time_lerp;
624 ffclock_convert_delta(ffdelta, ffth->period_lerp, &bt);
625 bintime_add(&ffth->tick_time_lerp, &bt);
626
627 ffth->tick_ffcount = fftimehands->tick_ffcount + ffdelta;
628
629 /*
630 * Assess the status of the clock, if the last update is too old, it is
631 * likely the synchronisation daemon is dead and the clock is free
632 * running.
633 */
634 if (ffclock_updated == 0) {
635 ffdelta = ffth->tick_ffcount - cest->update_ffcount;
636 ffclock_convert_delta(ffdelta, cest->period, &bt);
637 if (bt.sec > 2 * FFCLOCK_SKM_SCALE)
638 ffclock_status |= FFCLOCK_STA_UNSYNC;
639 }
640
641 /*
642 * If available, grab updated clock estimates and make them current.
643 * Recompute time at this tick using the updated estimates. The clock
644 * estimates passed the feed-forward synchronisation daemon may result
645 * in time conversion that is not monotonically increasing (just after
646 * the update). time_lerp is a particular linear interpolation over the
647 * synchronisation algo polling period that ensures monotonicity for the
648 * clock ids requesting it.
649 */
650 if (ffclock_updated > 0) {
651 bcopy(&ffclock_estimate, cest, sizeof(struct ffclock_estimate));
652 ffdelta = ffth->tick_ffcount - cest->update_ffcount;
653 ffth->tick_time = cest->update_time;
654 ffclock_convert_delta(ffdelta, cest->period, &bt);
655 bintime_add(&ffth->tick_time, &bt);
656
657 /* ffclock_reset sets ffclock_updated to INT8_MAX */
658 if (ffclock_updated == INT8_MAX)
659 ffth->tick_time_lerp = ffth->tick_time;
660
661 if (bintime_cmp(&ffth->tick_time, &ffth->tick_time_lerp, >))
662 forward_jump = 1;
663 else
664 forward_jump = 0;
665
666 bintime_clear(&gap_lerp);
667 if (forward_jump) {
668 gap_lerp = ffth->tick_time;
669 bintime_sub(&gap_lerp, &ffth->tick_time_lerp);
670 } else {
671 gap_lerp = ffth->tick_time_lerp;
672 bintime_sub(&gap_lerp, &ffth->tick_time);
673 }
674
675 /*
676 * The reset from the RTC clock may be far from accurate, and
677 * reducing the gap between real time and interpolated time
678 * could take a very long time if the interpolated clock insists
679 * on strict monotonicity. The clock is reset under very strict
680 * conditions (kernel time is known to be wrong and
681 * synchronization daemon has been restarted recently.
682 * ffclock_boottime absorbs the jump to ensure boot time is
683 * correct and uptime functions stay consistent.
684 */
685 if (((ffclock_status & FFCLOCK_STA_UNSYNC) == FFCLOCK_STA_UNSYNC) &&
686 ((cest->status & FFCLOCK_STA_UNSYNC) == 0) &&
687 ((cest->status & FFCLOCK_STA_WARMUP) == FFCLOCK_STA_WARMUP)) {
688 if (forward_jump)
689 bintime_add(&ffclock_boottime, &gap_lerp);
690 else
691 bintime_sub(&ffclock_boottime, &gap_lerp);
692 ffth->tick_time_lerp = ffth->tick_time;
693 bintime_clear(&gap_lerp);
694 }
695
696 ffclock_status = cest->status;
697 ffth->period_lerp = cest->period;
698
699 /*
700 * Compute corrected period used for the linear interpolation of
701 * time. The rate of linear interpolation is capped to 5000PPM
702 * (5ms/s).
703 */
704 if (bintime_isset(&gap_lerp)) {
705 ffdelta = cest->update_ffcount;
706 ffdelta -= fftimehands->cest.update_ffcount;
707 ffclock_convert_delta(ffdelta, cest->period, &bt);
708 polling = bt.sec;
709 bt.sec = 0;
710 bt.frac = 5000000 * (uint64_t)18446744073LL;
711 bintime_mul(&bt, polling);
712 if (bintime_cmp(&gap_lerp, &bt, >))
713 gap_lerp = bt;
714
715 /* Approximate 1 sec by 1-(1/2^64) to ease arithmetic */
716 frac = 0;
717 if (gap_lerp.sec > 0) {
718 frac -= 1;
719 frac /= ffdelta / gap_lerp.sec;
720 }
721 frac += gap_lerp.frac / ffdelta;
722
723 if (forward_jump)
724 ffth->period_lerp += frac;
725 else
726 ffth->period_lerp -= frac;
727 }
728
729 ffclock_updated = 0;
730 }
731 if (++ogen == 0)
732 ogen = 1;
733 ffth->gen = ogen;
734 fftimehands = ffth;
735 }
736
737 /*
738 * Adjust the fftimehands when the timecounter is changed. Stating the obvious,
739 * the old and new hardware counter cannot be read simultaneously. tc_windup()
740 * does read the two counters 'back to back', but a few cycles are effectively
741 * lost, and not accumulated in tick_ffcount. This is a fairly radical
742 * operation for a feed-forward synchronization daemon, and it is its job to not
743 * pushing irrelevant data to the kernel. Because there is no locking here,
744 * simply force to ignore pending or next update to give daemon a chance to
745 * realize the counter has changed.
746 */
747 static void
748 ffclock_change_tc(struct timehands *th)
749 {
750 struct fftimehands *ffth;
751 struct ffclock_estimate *cest;
752 struct timecounter *tc;
753 uint8_t ogen;
754
755 tc = th->th_counter;
756 ffth = fftimehands->next;
757 ogen = ffth->gen;
758 ffth->gen = 0;
759
760 cest = &ffth->cest;
761 bcopy(&(fftimehands->cest), cest, sizeof(struct ffclock_estimate));
762 cest->period = ((1ULL << 63) / tc->tc_frequency ) << 1;
763 cest->errb_abs = 0;
764 cest->errb_rate = 0;
765 cest->status |= FFCLOCK_STA_UNSYNC;
766
767 ffth->tick_ffcount = fftimehands->tick_ffcount;
768 ffth->tick_time_lerp = fftimehands->tick_time_lerp;
769 ffth->tick_time = fftimehands->tick_time;
770 ffth->period_lerp = cest->period;
771
772 /* Do not lock but ignore next update from synchronization daemon. */
773 ffclock_updated--;
774
775 if (++ogen == 0)
776 ogen = 1;
777 ffth->gen = ogen;
778 fftimehands = ffth;
779 }
780
781 /*
782 * Retrieve feed-forward counter and time of last kernel tick.
783 */
784 void
785 ffclock_last_tick(ffcounter *ffcount, struct bintime *bt, uint32_t flags)
786 {
787 struct fftimehands *ffth;
788 uint8_t gen;
789
790 /*
791 * No locking but check generation has not changed. Also need to make
792 * sure ffdelta is positive, i.e. ffcount > tick_ffcount.
793 */
794 do {
795 ffth = fftimehands;
796 gen = ffth->gen;
797 if ((flags & FFCLOCK_LERP) == FFCLOCK_LERP)
798 *bt = ffth->tick_time_lerp;
799 else
800 *bt = ffth->tick_time;
801 *ffcount = ffth->tick_ffcount;
802 } while (gen == 0 || gen != ffth->gen);
803 }
804
805 /*
806 * Absolute clock conversion. Low level function to convert ffcounter to
807 * bintime. The ffcounter is converted using the current ffclock period estimate
808 * or the "interpolated period" to ensure monotonicity.
809 * NOTE: this conversion may have been deferred, and the clock updated since the
810 * hardware counter has been read.
811 */
812 void
813 ffclock_convert_abs(ffcounter ffcount, struct bintime *bt, uint32_t flags)
814 {
815 struct fftimehands *ffth;
816 struct bintime bt2;
817 ffcounter ffdelta;
818 uint8_t gen;
819
820 /*
821 * No locking but check generation has not changed. Also need to make
822 * sure ffdelta is positive, i.e. ffcount > tick_ffcount.
823 */
824 do {
825 ffth = fftimehands;
826 gen = ffth->gen;
827 if (ffcount > ffth->tick_ffcount)
828 ffdelta = ffcount - ffth->tick_ffcount;
829 else
830 ffdelta = ffth->tick_ffcount - ffcount;
831
832 if ((flags & FFCLOCK_LERP) == FFCLOCK_LERP) {
833 *bt = ffth->tick_time_lerp;
834 ffclock_convert_delta(ffdelta, ffth->period_lerp, &bt2);
835 } else {
836 *bt = ffth->tick_time;
837 ffclock_convert_delta(ffdelta, ffth->cest.period, &bt2);
838 }
839
840 if (ffcount > ffth->tick_ffcount)
841 bintime_add(bt, &bt2);
842 else
843 bintime_sub(bt, &bt2);
844 } while (gen == 0 || gen != ffth->gen);
845 }
846
847 /*
848 * Difference clock conversion.
849 * Low level function to Convert a time interval measured in RAW counter units
850 * into bintime. The difference clock allows measuring small intervals much more
851 * reliably than the absolute clock.
852 */
853 void
854 ffclock_convert_diff(ffcounter ffdelta, struct bintime *bt)
855 {
856 struct fftimehands *ffth;
857 uint8_t gen;
858
859 /* No locking but check generation has not changed. */
860 do {
861 ffth = fftimehands;
862 gen = ffth->gen;
863 ffclock_convert_delta(ffdelta, ffth->cest.period, bt);
864 } while (gen == 0 || gen != ffth->gen);
865 }
866
867 /*
868 * Access to current ffcounter value.
869 */
870 void
871 ffclock_read_counter(ffcounter *ffcount)
872 {
873 struct timehands *th;
874 struct fftimehands *ffth;
875 unsigned int gen, delta;
876
877 /*
878 * ffclock_windup() called from tc_windup(), safe to rely on
879 * th->th_generation only, for correct delta and ffcounter.
880 */
881 do {
882 th = timehands;
883 gen = th->th_generation;
884 ffth = fftimehands;
885 delta = tc_delta(th);
886 *ffcount = ffth->tick_ffcount;
887 } while (gen == 0 || gen != th->th_generation);
888
889 *ffcount += delta;
890 }
891
892 void
893 binuptime(struct bintime *bt)
894 {
895
896 binuptime_fromclock(bt, sysclock_active);
897 }
898
899 void
900 nanouptime(struct timespec *tsp)
901 {
902
903 nanouptime_fromclock(tsp, sysclock_active);
904 }
905
906 void
907 microuptime(struct timeval *tvp)
908 {
909
910 microuptime_fromclock(tvp, sysclock_active);
911 }
912
913 void
914 bintime(struct bintime *bt)
915 {
916
917 bintime_fromclock(bt, sysclock_active);
918 }
919
920 void
921 nanotime(struct timespec *tsp)
922 {
923
924 nanotime_fromclock(tsp, sysclock_active);
925 }
926
927 void
928 microtime(struct timeval *tvp)
929 {
930
931 microtime_fromclock(tvp, sysclock_active);
932 }
933
934 void
935 getbinuptime(struct bintime *bt)
936 {
937
938 getbinuptime_fromclock(bt, sysclock_active);
939 }
940
941 void
942 getnanouptime(struct timespec *tsp)
943 {
944
945 getnanouptime_fromclock(tsp, sysclock_active);
946 }
947
948 void
949 getmicrouptime(struct timeval *tvp)
950 {
951
952 getmicrouptime_fromclock(tvp, sysclock_active);
953 }
954
955 void
956 getbintime(struct bintime *bt)
957 {
958
959 getbintime_fromclock(bt, sysclock_active);
960 }
961
962 void
963 getnanotime(struct timespec *tsp)
964 {
965
966 getnanotime_fromclock(tsp, sysclock_active);
967 }
968
969 void
970 getmicrotime(struct timeval *tvp)
971 {
972
973 getmicrouptime_fromclock(tvp, sysclock_active);
974 }
975
976 #endif /* FFCLOCK */
977
978 /*
979 * This is a clone of getnanotime and used for walltimestamps.
980 * The dtrace_ prefix prevents fbt from creating probes for
981 * it so walltimestamp can be safely used in all fbt probes.
982 */
983 void
984 dtrace_getnanotime(struct timespec *tsp)
985 {
986 struct timehands *th;
987 u_int gen;
988
989 do {
990 th = timehands;
991 gen = th->th_generation;
992 *tsp = th->th_nanotime;
993 } while (gen == 0 || gen != th->th_generation);
994 }
995
996 /*
997 * System clock currently providing time to the system. Modifiable via sysctl
998 * when the FFCLOCK option is defined.
999 */
1000 int sysclock_active = SYSCLOCK_FBCK;
1001
1002 /* Internal NTP status and error estimates. */
1003 extern int time_status;
1004 extern long time_esterror;
1005
1006 /*
1007 * Take a snapshot of sysclock data which can be used to compare system clocks
1008 * and generate timestamps after the fact.
1009 */
1010 void
1011 sysclock_getsnapshot(struct sysclock_snap *clock_snap, int fast)
1012 {
1013 struct fbclock_info *fbi;
1014 struct timehands *th;
1015 struct bintime bt;
1016 unsigned int delta, gen;
1017 #ifdef FFCLOCK
1018 ffcounter ffcount;
1019 struct fftimehands *ffth;
1020 struct ffclock_info *ffi;
1021 struct ffclock_estimate cest;
1022
1023 ffi = &clock_snap->ff_info;
1024 #endif
1025
1026 fbi = &clock_snap->fb_info;
1027 delta = 0;
1028
1029 do {
1030 th = timehands;
1031 gen = th->th_generation;
1032 fbi->th_scale = th->th_scale;
1033 fbi->tick_time = th->th_offset;
1034 #ifdef FFCLOCK
1035 ffth = fftimehands;
1036 ffi->tick_time = ffth->tick_time_lerp;
1037 ffi->tick_time_lerp = ffth->tick_time_lerp;
1038 ffi->period = ffth->cest.period;
1039 ffi->period_lerp = ffth->period_lerp;
1040 clock_snap->ffcount = ffth->tick_ffcount;
1041 cest = ffth->cest;
1042 #endif
1043 if (!fast)
1044 delta = tc_delta(th);
1045 } while (gen == 0 || gen != th->th_generation);
1046
1047 clock_snap->delta = delta;
1048 clock_snap->sysclock_active = sysclock_active;
1049
1050 /* Record feedback clock status and error. */
1051 clock_snap->fb_info.status = time_status;
1052 /* XXX: Very crude estimate of feedback clock error. */
1053 bt.sec = time_esterror / 1000000;
1054 bt.frac = ((time_esterror - bt.sec) * 1000000) *
1055 (uint64_t)18446744073709ULL;
1056 clock_snap->fb_info.error = bt;
1057
1058 #ifdef FFCLOCK
1059 if (!fast)
1060 clock_snap->ffcount += delta;
1061
1062 /* Record feed-forward clock leap second adjustment. */
1063 ffi->leapsec_adjustment = cest.leapsec_total;
1064 if (clock_snap->ffcount > cest.leapsec_next)
1065 ffi->leapsec_adjustment -= cest.leapsec;
1066
1067 /* Record feed-forward clock status and error. */
1068 clock_snap->ff_info.status = cest.status;
1069 ffcount = clock_snap->ffcount - cest.update_ffcount;
1070 ffclock_convert_delta(ffcount, cest.period, &bt);
1071 /* 18446744073709 = int(2^64/1e12), err_bound_rate in [ps/s]. */
1072 bintime_mul(&bt, cest.errb_rate * (uint64_t)18446744073709ULL);
1073 /* 18446744073 = int(2^64 / 1e9), since err_abs in [ns]. */
1074 bintime_addx(&bt, cest.errb_abs * (uint64_t)18446744073ULL);
1075 clock_snap->ff_info.error = bt;
1076 #endif
1077 }
1078
1079 /*
1080 * Convert a sysclock snapshot into a struct bintime based on the specified
1081 * clock source and flags.
1082 */
1083 int
1084 sysclock_snap2bintime(struct sysclock_snap *cs, struct bintime *bt,
1085 int whichclock, uint32_t flags)
1086 {
1087 #ifdef FFCLOCK
1088 struct bintime bt2;
1089 uint64_t period;
1090 #endif
1091
1092 switch (whichclock) {
1093 case SYSCLOCK_FBCK:
1094 *bt = cs->fb_info.tick_time;
1095
1096 /* If snapshot was created with !fast, delta will be >0. */
1097 if (cs->delta > 0)
1098 bintime_addx(bt, cs->fb_info.th_scale * cs->delta);
1099
1100 if ((flags & FBCLOCK_UPTIME) == 0)
1101 bintime_add(bt, &boottimebin);
1102 break;
1103 #ifdef FFCLOCK
1104 case SYSCLOCK_FFWD:
1105 if (flags & FFCLOCK_LERP) {
1106 *bt = cs->ff_info.tick_time_lerp;
1107 period = cs->ff_info.period_lerp;
1108 } else {
1109 *bt = cs->ff_info.tick_time;
1110 period = cs->ff_info.period;
1111 }
1112
1113 /* If snapshot was created with !fast, delta will be >0. */
1114 if (cs->delta > 0) {
1115 ffclock_convert_delta(cs->delta, period, &bt2);
1116 bintime_add(bt, &bt2);
1117 }
1118
1119 /* Leap second adjustment. */
1120 if (flags & FFCLOCK_LEAPSEC)
1121 bt->sec -= cs->ff_info.leapsec_adjustment;
1122
1123 /* Boot time adjustment, for uptime/monotonic clocks. */
1124 if (flags & FFCLOCK_UPTIME)
1125 bintime_sub(bt, &ffclock_boottime);
1126 break;
1127 #endif
1128 default:
1129 return (EINVAL);
1130 break;
1131 }
1132
1133 return (0);
1134 }
1135
1136 /*
1137 * Initialize a new timecounter and possibly use it.
1138 */
1139 void
1140 tc_init(struct timecounter *tc)
1141 {
1142 u_int u;
1143 struct sysctl_oid *tc_root;
1144
1145 u = tc->tc_frequency / tc->tc_counter_mask;
1146 /* XXX: We need some margin here, 10% is a guess */
1147 u *= 11;
1148 u /= 10;
1149 if (u > hz && tc->tc_quality >= 0) {
1150 tc->tc_quality = -2000;
1151 if (bootverbose) {
1152 printf("Timecounter \"%s\" frequency %ju Hz",
1153 tc->tc_name, (uintmax_t)tc->tc_frequency);
1154 printf(" -- Insufficient hz, needs at least %u\n", u);
1155 }
1156 } else if (tc->tc_quality >= 0 || bootverbose) {
1157 printf("Timecounter \"%s\" frequency %ju Hz quality %d\n",
1158 tc->tc_name, (uintmax_t)tc->tc_frequency,
1159 tc->tc_quality);
1160 }
1161
1162 tc->tc_next = timecounters;
1163 timecounters = tc;
1164 /*
1165 * Set up sysctl tree for this counter.
1166 */
1167 tc_root = SYSCTL_ADD_NODE(NULL,
1168 SYSCTL_STATIC_CHILDREN(_kern_timecounter_tc), OID_AUTO, tc->tc_name,
1169 CTLFLAG_RW, 0, "timecounter description");
1170 SYSCTL_ADD_UINT(NULL, SYSCTL_CHILDREN(tc_root), OID_AUTO,
1171 "mask", CTLFLAG_RD, &(tc->tc_counter_mask), 0,
1172 "mask for implemented bits");
1173 SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(tc_root), OID_AUTO,
1174 "counter", CTLTYPE_UINT | CTLFLAG_RD, tc, sizeof(*tc),
1175 sysctl_kern_timecounter_get, "IU", "current timecounter value");
1176 SYSCTL_ADD_PROC(NULL, SYSCTL_CHILDREN(tc_root), OID_AUTO,
1177 "frequency", CTLTYPE_U64 | CTLFLAG_RD, tc, sizeof(*tc),
1178 sysctl_kern_timecounter_freq, "QU", "timecounter frequency");
1179 SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(tc_root), OID_AUTO,
1180 "quality", CTLFLAG_RD, &(tc->tc_quality), 0,
1181 "goodness of time counter");
1182 /*
1183 * Never automatically use a timecounter with negative quality.
1184 * Even though we run on the dummy counter, switching here may be
1185 * worse since this timecounter may not be monotonous.
1186 */
1187 if (tc->tc_quality < 0)
1188 return;
1189 if (tc->tc_quality < timecounter->tc_quality)
1190 return;
1191 if (tc->tc_quality == timecounter->tc_quality &&
1192 tc->tc_frequency < timecounter->tc_frequency)
1193 return;
1194 (void)tc->tc_get_timecount(tc);
1195 (void)tc->tc_get_timecount(tc);
1196 timecounter = tc;
1197 }
1198
1199 /* Report the frequency of the current timecounter. */
1200 uint64_t
1201 tc_getfrequency(void)
1202 {
1203
1204 return (timehands->th_counter->tc_frequency);
1205 }
1206
1207 /*
1208 * Step our concept of UTC. This is done by modifying our estimate of
1209 * when we booted.
1210 * XXX: not locked.
1211 */
1212 void
1213 tc_setclock(struct timespec *ts)
1214 {
1215 struct timespec tbef, taft;
1216 struct bintime bt, bt2;
1217
1218 cpu_tick_calibrate(1);
1219 nanotime(&tbef);
1220 timespec2bintime(ts, &bt);
1221 binuptime(&bt2);
1222 bintime_sub(&bt, &bt2);
1223 bintime_add(&bt2, &boottimebin);
1224 boottimebin = bt;
1225 bintime2timeval(&bt, &boottime);
1226
1227 /* XXX fiddle all the little crinkly bits around the fiords... */
1228 tc_windup();
1229 nanotime(&taft);
1230 if (timestepwarnings) {
1231 log(LOG_INFO,
1232 "Time stepped from %jd.%09ld to %jd.%09ld (%jd.%09ld)\n",
1233 (intmax_t)tbef.tv_sec, tbef.tv_nsec,
1234 (intmax_t)taft.tv_sec, taft.tv_nsec,
1235 (intmax_t)ts->tv_sec, ts->tv_nsec);
1236 }
1237 cpu_tick_calibrate(1);
1238 }
1239
1240 /*
1241 * Initialize the next struct timehands in the ring and make
1242 * it the active timehands. Along the way we might switch to a different
1243 * timecounter and/or do seconds processing in NTP. Slightly magic.
1244 */
1245 static void
1246 tc_windup(void)
1247 {
1248 struct bintime bt;
1249 struct timehands *th, *tho;
1250 uint64_t scale;
1251 u_int delta, ncount, ogen;
1252 int i;
1253 time_t t;
1254
1255 /*
1256 * Make the next timehands a copy of the current one, but do not
1257 * overwrite the generation or next pointer. While we update
1258 * the contents, the generation must be zero.
1259 */
1260 tho = timehands;
1261 th = tho->th_next;
1262 ogen = th->th_generation;
1263 th->th_generation = 0;
1264 bcopy(tho, th, offsetof(struct timehands, th_generation));
1265
1266 /*
1267 * Capture a timecounter delta on the current timecounter and if
1268 * changing timecounters, a counter value from the new timecounter.
1269 * Update the offset fields accordingly.
1270 */
1271 delta = tc_delta(th);
1272 if (th->th_counter != timecounter)
1273 ncount = timecounter->tc_get_timecount(timecounter);
1274 else
1275 ncount = 0;
1276 #ifdef FFCLOCK
1277 ffclock_windup(delta);
1278 #endif
1279 th->th_offset_count += delta;
1280 th->th_offset_count &= th->th_counter->tc_counter_mask;
1281 while (delta > th->th_counter->tc_frequency) {
1282 /* Eat complete unadjusted seconds. */
1283 delta -= th->th_counter->tc_frequency;
1284 th->th_offset.sec++;
1285 }
1286 if ((delta > th->th_counter->tc_frequency / 2) &&
1287 (th->th_scale * delta < ((uint64_t)1 << 63))) {
1288 /* The product th_scale * delta just barely overflows. */
1289 th->th_offset.sec++;
1290 }
1291 bintime_addx(&th->th_offset, th->th_scale * delta);
1292
1293 /*
1294 * Hardware latching timecounters may not generate interrupts on
1295 * PPS events, so instead we poll them. There is a finite risk that
1296 * the hardware might capture a count which is later than the one we
1297 * got above, and therefore possibly in the next NTP second which might
1298 * have a different rate than the current NTP second. It doesn't
1299 * matter in practice.
1300 */
1301 if (tho->th_counter->tc_poll_pps)
1302 tho->th_counter->tc_poll_pps(tho->th_counter);
1303
1304 /*
1305 * Deal with NTP second processing. The for loop normally
1306 * iterates at most once, but in extreme situations it might
1307 * keep NTP sane if timeouts are not run for several seconds.
1308 * At boot, the time step can be large when the TOD hardware
1309 * has been read, so on really large steps, we call
1310 * ntp_update_second only twice. We need to call it twice in
1311 * case we missed a leap second.
1312 */
1313 bt = th->th_offset;
1314 bintime_add(&bt, &boottimebin);
1315 i = bt.sec - tho->th_microtime.tv_sec;
1316 if (i > LARGE_STEP)
1317 i = 2;
1318 for (; i > 0; i--) {
1319 t = bt.sec;
1320 ntp_update_second(&th->th_adjustment, &bt.sec);
1321 if (bt.sec != t)
1322 boottimebin.sec += bt.sec - t;
1323 }
1324 /* Update the UTC timestamps used by the get*() functions. */
1325 /* XXX shouldn't do this here. Should force non-`get' versions. */
1326 bintime2timeval(&bt, &th->th_microtime);
1327 bintime2timespec(&bt, &th->th_nanotime);
1328
1329 /* Now is a good time to change timecounters. */
1330 if (th->th_counter != timecounter) {
1331 #ifndef __arm__
1332 if ((timecounter->tc_flags & TC_FLAGS_C2STOP) != 0)
1333 cpu_disable_c2_sleep++;
1334 if ((th->th_counter->tc_flags & TC_FLAGS_C2STOP) != 0)
1335 cpu_disable_c2_sleep--;
1336 #endif
1337 th->th_counter = timecounter;
1338 th->th_offset_count = ncount;
1339 tc_min_ticktock_freq = max(1, timecounter->tc_frequency /
1340 (((uint64_t)timecounter->tc_counter_mask + 1) / 3));
1341 #ifdef FFCLOCK
1342 ffclock_change_tc(th);
1343 #endif
1344 }
1345
1346 /*-
1347 * Recalculate the scaling factor. We want the number of 1/2^64
1348 * fractions of a second per period of the hardware counter, taking
1349 * into account the th_adjustment factor which the NTP PLL/adjtime(2)
1350 * processing provides us with.
1351 *
1352 * The th_adjustment is nanoseconds per second with 32 bit binary
1353 * fraction and we want 64 bit binary fraction of second:
1354 *
1355 * x = a * 2^32 / 10^9 = a * 4.294967296
1356 *
1357 * The range of th_adjustment is +/- 5000PPM so inside a 64bit int
1358 * we can only multiply by about 850 without overflowing, that
1359 * leaves no suitably precise fractions for multiply before divide.
1360 *
1361 * Divide before multiply with a fraction of 2199/512 results in a
1362 * systematic undercompensation of 10PPM of th_adjustment. On a
1363 * 5000PPM adjustment this is a 0.05PPM error. This is acceptable.
1364 *
1365 * We happily sacrifice the lowest of the 64 bits of our result
1366 * to the goddess of code clarity.
1367 *
1368 */
1369 scale = (uint64_t)1 << 63;
1370 scale += (th->th_adjustment / 1024) * 2199;
1371 scale /= th->th_counter->tc_frequency;
1372 th->th_scale = scale * 2;
1373
1374 /*
1375 * Now that the struct timehands is again consistent, set the new
1376 * generation number, making sure to not make it zero.
1377 */
1378 if (++ogen == 0)
1379 ogen = 1;
1380 th->th_generation = ogen;
1381
1382 /* Go live with the new struct timehands. */
1383 #ifdef FFCLOCK
1384 switch (sysclock_active) {
1385 case SYSCLOCK_FBCK:
1386 #endif
1387 time_second = th->th_microtime.tv_sec;
1388 time_uptime = th->th_offset.sec;
1389 #ifdef FFCLOCK
1390 break;
1391 case SYSCLOCK_FFWD:
1392 time_second = fftimehands->tick_time_lerp.sec;
1393 time_uptime = fftimehands->tick_time_lerp.sec - ffclock_boottime.sec;
1394 break;
1395 }
1396 #endif
1397
1398 timehands = th;
1399 timekeep_push_vdso();
1400 }
1401
1402 /* Report or change the active timecounter hardware. */
1403 static int
1404 sysctl_kern_timecounter_hardware(SYSCTL_HANDLER_ARGS)
1405 {
1406 char newname[32];
1407 struct timecounter *newtc, *tc;
1408 int error;
1409
1410 tc = timecounter;
1411 strlcpy(newname, tc->tc_name, sizeof(newname));
1412
1413 error = sysctl_handle_string(oidp, &newname[0], sizeof(newname), req);
1414 if (error != 0 || req->newptr == NULL ||
1415 strcmp(newname, tc->tc_name) == 0)
1416 return (error);
1417 for (newtc = timecounters; newtc != NULL; newtc = newtc->tc_next) {
1418 if (strcmp(newname, newtc->tc_name) != 0)
1419 continue;
1420
1421 /* Warm up new timecounter. */
1422 (void)newtc->tc_get_timecount(newtc);
1423 (void)newtc->tc_get_timecount(newtc);
1424
1425 timecounter = newtc;
1426 timekeep_push_vdso();
1427 return (0);
1428 }
1429 return (EINVAL);
1430 }
1431
1432 SYSCTL_PROC(_kern_timecounter, OID_AUTO, hardware, CTLTYPE_STRING | CTLFLAG_RW,
1433 0, 0, sysctl_kern_timecounter_hardware, "A",
1434 "Timecounter hardware selected");
1435
1436
1437 /* Report or change the active timecounter hardware. */
1438 static int
1439 sysctl_kern_timecounter_choice(SYSCTL_HANDLER_ARGS)
1440 {
1441 char buf[32], *spc;
1442 struct timecounter *tc;
1443 int error;
1444
1445 spc = "";
1446 error = 0;
1447 for (tc = timecounters; error == 0 && tc != NULL; tc = tc->tc_next) {
1448 sprintf(buf, "%s%s(%d)",
1449 spc, tc->tc_name, tc->tc_quality);
1450 error = SYSCTL_OUT(req, buf, strlen(buf));
1451 spc = " ";
1452 }
1453 return (error);
1454 }
1455
1456 SYSCTL_PROC(_kern_timecounter, OID_AUTO, choice, CTLTYPE_STRING | CTLFLAG_RD,
1457 0, 0, sysctl_kern_timecounter_choice, "A", "Timecounter hardware detected");
1458
1459 /*
1460 * RFC 2783 PPS-API implementation.
1461 */
1462
1463 /*
1464 * Return true if the driver is aware of the abi version extensions in the
1465 * pps_state structure, and it supports at least the given abi version number.
1466 */
1467 static inline int
1468 abi_aware(struct pps_state *pps, int vers)
1469 {
1470
1471 return ((pps->kcmode & KCMODE_ABIFLAG) && pps->driver_abi >= vers);
1472 }
1473
1474 static int
1475 pps_fetch(struct pps_fetch_args *fapi, struct pps_state *pps)
1476 {
1477 int err, timo;
1478 pps_seq_t aseq, cseq;
1479 struct timeval tv;
1480
1481 if (fapi->tsformat && fapi->tsformat != PPS_TSFMT_TSPEC)
1482 return (EINVAL);
1483
1484 /*
1485 * If no timeout is requested, immediately return whatever values were
1486 * most recently captured. If timeout seconds is -1, that's a request
1487 * to block without a timeout. WITNESS won't let us sleep forever
1488 * without a lock (we really don't need a lock), so just repeatedly
1489 * sleep a long time.
1490 */
1491 if (fapi->timeout.tv_sec || fapi->timeout.tv_nsec) {
1492 if (fapi->timeout.tv_sec == -1)
1493 timo = 0x7fffffff;
1494 else {
1495 tv.tv_sec = fapi->timeout.tv_sec;
1496 tv.tv_usec = fapi->timeout.tv_nsec / 1000;
1497 timo = tvtohz(&tv);
1498 }
1499 aseq = pps->ppsinfo.assert_sequence;
1500 cseq = pps->ppsinfo.clear_sequence;
1501 while (aseq == pps->ppsinfo.assert_sequence &&
1502 cseq == pps->ppsinfo.clear_sequence) {
1503 if (abi_aware(pps, 1) && pps->driver_mtx != NULL) {
1504 if (pps->flags & PPSFLAG_MTX_SPIN) {
1505 err = msleep_spin(pps, pps->driver_mtx,
1506 "ppsfch", timo);
1507 } else {
1508 err = msleep(pps, pps->driver_mtx, PCATCH,
1509 "ppsfch", timo);
1510 }
1511 } else {
1512 err = tsleep(pps, PCATCH, "ppsfch", timo);
1513 }
1514 if (err == EWOULDBLOCK && fapi->timeout.tv_sec == -1) {
1515 continue;
1516 } else if (err != 0) {
1517 return (err);
1518 }
1519 }
1520 }
1521
1522 pps->ppsinfo.current_mode = pps->ppsparam.mode;
1523 fapi->pps_info_buf = pps->ppsinfo;
1524
1525 return (0);
1526 }
1527
1528 int
1529 pps_ioctl(u_long cmd, caddr_t data, struct pps_state *pps)
1530 {
1531 pps_params_t *app;
1532 struct pps_fetch_args *fapi;
1533 #ifdef FFCLOCK
1534 struct pps_fetch_ffc_args *fapi_ffc;
1535 #endif
1536 #ifdef PPS_SYNC
1537 struct pps_kcbind_args *kapi;
1538 #endif
1539
1540 KASSERT(pps != NULL, ("NULL pps pointer in pps_ioctl"));
1541 switch (cmd) {
1542 case PPS_IOC_CREATE:
1543 return (0);
1544 case PPS_IOC_DESTROY:
1545 return (0);
1546 case PPS_IOC_SETPARAMS:
1547 app = (pps_params_t *)data;
1548 if (app->mode & ~pps->ppscap)
1549 return (EINVAL);
1550 #ifdef FFCLOCK
1551 /* Ensure only a single clock is selected for ffc timestamp. */
1552 if ((app->mode & PPS_TSCLK_MASK) == PPS_TSCLK_MASK)
1553 return (EINVAL);
1554 #endif
1555 pps->ppsparam = *app;
1556 return (0);
1557 case PPS_IOC_GETPARAMS:
1558 app = (pps_params_t *)data;
1559 *app = pps->ppsparam;
1560 app->api_version = PPS_API_VERS_1;
1561 return (0);
1562 case PPS_IOC_GETCAP:
1563 *(int*)data = pps->ppscap;
1564 return (0);
1565 case PPS_IOC_FETCH:
1566 fapi = (struct pps_fetch_args *)data;
1567 return (pps_fetch(fapi, pps));
1568 #ifdef FFCLOCK
1569 case PPS_IOC_FETCH_FFCOUNTER:
1570 fapi_ffc = (struct pps_fetch_ffc_args *)data;
1571 if (fapi_ffc->tsformat && fapi_ffc->tsformat !=
1572 PPS_TSFMT_TSPEC)
1573 return (EINVAL);
1574 if (fapi_ffc->timeout.tv_sec || fapi_ffc->timeout.tv_nsec)
1575 return (EOPNOTSUPP);
1576 pps->ppsinfo_ffc.current_mode = pps->ppsparam.mode;
1577 fapi_ffc->pps_info_buf_ffc = pps->ppsinfo_ffc;
1578 /* Overwrite timestamps if feedback clock selected. */
1579 switch (pps->ppsparam.mode & PPS_TSCLK_MASK) {
1580 case PPS_TSCLK_FBCK:
1581 fapi_ffc->pps_info_buf_ffc.assert_timestamp =
1582 pps->ppsinfo.assert_timestamp;
1583 fapi_ffc->pps_info_buf_ffc.clear_timestamp =
1584 pps->ppsinfo.clear_timestamp;
1585 break;
1586 case PPS_TSCLK_FFWD:
1587 break;
1588 default:
1589 break;
1590 }
1591 return (0);
1592 #endif /* FFCLOCK */
1593 case PPS_IOC_KCBIND:
1594 #ifdef PPS_SYNC
1595 kapi = (struct pps_kcbind_args *)data;
1596 /* XXX Only root should be able to do this */
1597 if (kapi->tsformat && kapi->tsformat != PPS_TSFMT_TSPEC)
1598 return (EINVAL);
1599 if (kapi->kernel_consumer != PPS_KC_HARDPPS)
1600 return (EINVAL);
1601 if (kapi->edge & ~pps->ppscap)
1602 return (EINVAL);
1603 pps->kcmode = (kapi->edge & KCMODE_EDGEMASK) |
1604 (pps->kcmode & KCMODE_ABIFLAG);
1605 return (0);
1606 #else
1607 return (EOPNOTSUPP);
1608 #endif
1609 default:
1610 return (ENOIOCTL);
1611 }
1612 }
1613
1614 void
1615 pps_init(struct pps_state *pps)
1616 {
1617 pps->ppscap |= PPS_TSFMT_TSPEC | PPS_CANWAIT;
1618 if (pps->ppscap & PPS_CAPTUREASSERT)
1619 pps->ppscap |= PPS_OFFSETASSERT;
1620 if (pps->ppscap & PPS_CAPTURECLEAR)
1621 pps->ppscap |= PPS_OFFSETCLEAR;
1622 #ifdef FFCLOCK
1623 pps->ppscap |= PPS_TSCLK_MASK;
1624 #endif
1625 pps->kcmode &= ~KCMODE_ABIFLAG;
1626 }
1627
1628 void
1629 pps_init_abi(struct pps_state *pps)
1630 {
1631
1632 pps_init(pps);
1633 if (pps->driver_abi > 0) {
1634 pps->kcmode |= KCMODE_ABIFLAG;
1635 pps->kernel_abi = PPS_ABI_VERSION;
1636 }
1637 }
1638
1639 void
1640 pps_capture(struct pps_state *pps)
1641 {
1642 struct timehands *th;
1643
1644 KASSERT(pps != NULL, ("NULL pps pointer in pps_capture"));
1645 th = timehands;
1646 pps->capgen = th->th_generation;
1647 pps->capth = th;
1648 #ifdef FFCLOCK
1649 pps->capffth = fftimehands;
1650 #endif
1651 pps->capcount = th->th_counter->tc_get_timecount(th->th_counter);
1652 if (pps->capgen != th->th_generation)
1653 pps->capgen = 0;
1654 }
1655
1656 void
1657 pps_event(struct pps_state *pps, int event)
1658 {
1659 struct bintime bt;
1660 struct timespec ts, *tsp, *osp;
1661 u_int tcount, *pcount;
1662 int foff, fhard;
1663 pps_seq_t *pseq;
1664 #ifdef FFCLOCK
1665 struct timespec *tsp_ffc;
1666 pps_seq_t *pseq_ffc;
1667 ffcounter *ffcount;
1668 #endif
1669
1670 KASSERT(pps != NULL, ("NULL pps pointer in pps_event"));
1671 /* If the timecounter was wound up underneath us, bail out. */
1672 if (pps->capgen == 0 || pps->capgen != pps->capth->th_generation)
1673 return;
1674
1675 /* Things would be easier with arrays. */
1676 if (event == PPS_CAPTUREASSERT) {
1677 tsp = &pps->ppsinfo.assert_timestamp;
1678 osp = &pps->ppsparam.assert_offset;
1679 foff = pps->ppsparam.mode & PPS_OFFSETASSERT;
1680 fhard = pps->kcmode & PPS_CAPTUREASSERT;
1681 pcount = &pps->ppscount[0];
1682 pseq = &pps->ppsinfo.assert_sequence;
1683 #ifdef FFCLOCK
1684 ffcount = &pps->ppsinfo_ffc.assert_ffcount;
1685 tsp_ffc = &pps->ppsinfo_ffc.assert_timestamp;
1686 pseq_ffc = &pps->ppsinfo_ffc.assert_sequence;
1687 #endif
1688 } else {
1689 tsp = &pps->ppsinfo.clear_timestamp;
1690 osp = &pps->ppsparam.clear_offset;
1691 foff = pps->ppsparam.mode & PPS_OFFSETCLEAR;
1692 fhard = pps->kcmode & PPS_CAPTURECLEAR;
1693 pcount = &pps->ppscount[1];
1694 pseq = &pps->ppsinfo.clear_sequence;
1695 #ifdef FFCLOCK
1696 ffcount = &pps->ppsinfo_ffc.clear_ffcount;
1697 tsp_ffc = &pps->ppsinfo_ffc.clear_timestamp;
1698 pseq_ffc = &pps->ppsinfo_ffc.clear_sequence;
1699 #endif
1700 }
1701
1702 /*
1703 * If the timecounter changed, we cannot compare the count values, so
1704 * we have to drop the rest of the PPS-stuff until the next event.
1705 */
1706 if (pps->ppstc != pps->capth->th_counter) {
1707 pps->ppstc = pps->capth->th_counter;
1708 *pcount = pps->capcount;
1709 pps->ppscount[2] = pps->capcount;
1710 return;
1711 }
1712
1713 /* Convert the count to a timespec. */
1714 tcount = pps->capcount - pps->capth->th_offset_count;
1715 tcount &= pps->capth->th_counter->tc_counter_mask;
1716 bt = pps->capth->th_offset;
1717 bintime_addx(&bt, pps->capth->th_scale * tcount);
1718 bintime_add(&bt, &boottimebin);
1719 bintime2timespec(&bt, &ts);
1720
1721 /* If the timecounter was wound up underneath us, bail out. */
1722 if (pps->capgen != pps->capth->th_generation)
1723 return;
1724
1725 *pcount = pps->capcount;
1726 (*pseq)++;
1727 *tsp = ts;
1728
1729 if (foff) {
1730 timespecadd(tsp, osp);
1731 if (tsp->tv_nsec < 0) {
1732 tsp->tv_nsec += 1000000000;
1733 tsp->tv_sec -= 1;
1734 }
1735 }
1736
1737 #ifdef FFCLOCK
1738 *ffcount = pps->capffth->tick_ffcount + tcount;
1739 bt = pps->capffth->tick_time;
1740 ffclock_convert_delta(tcount, pps->capffth->cest.period, &bt);
1741 bintime_add(&bt, &pps->capffth->tick_time);
1742 bintime2timespec(&bt, &ts);
1743 (*pseq_ffc)++;
1744 *tsp_ffc = ts;
1745 #endif
1746
1747 #ifdef PPS_SYNC
1748 if (fhard) {
1749 uint64_t scale;
1750
1751 /*
1752 * Feed the NTP PLL/FLL.
1753 * The FLL wants to know how many (hardware) nanoseconds
1754 * elapsed since the previous event.
1755 */
1756 tcount = pps->capcount - pps->ppscount[2];
1757 pps->ppscount[2] = pps->capcount;
1758 tcount &= pps->capth->th_counter->tc_counter_mask;
1759 scale = (uint64_t)1 << 63;
1760 scale /= pps->capth->th_counter->tc_frequency;
1761 scale *= 2;
1762 bt.sec = 0;
1763 bt.frac = 0;
1764 bintime_addx(&bt, scale * tcount);
1765 bintime2timespec(&bt, &ts);
1766 hardpps(tsp, ts.tv_nsec + 1000000000 * ts.tv_sec);
1767 }
1768 #endif
1769
1770 /* Wakeup anyone sleeping in pps_fetch(). */
1771 wakeup(pps);
1772 }
1773
1774 /*
1775 * Timecounters need to be updated every so often to prevent the hardware
1776 * counter from overflowing. Updating also recalculates the cached values
1777 * used by the get*() family of functions, so their precision depends on
1778 * the update frequency.
1779 */
1780
1781 static int tc_tick;
1782 SYSCTL_INT(_kern_timecounter, OID_AUTO, tick, CTLFLAG_RD, &tc_tick, 0,
1783 "Approximate number of hardclock ticks in a millisecond");
1784
1785 void
1786 tc_ticktock(int cnt)
1787 {
1788 static int count;
1789
1790 count += cnt;
1791 if (count < tc_tick)
1792 return;
1793 count = 0;
1794 tc_windup();
1795 }
1796
1797 static void __inline
1798 tc_adjprecision(void)
1799 {
1800 int t;
1801
1802 if (tc_timepercentage > 0) {
1803 t = (99 + tc_timepercentage) / tc_timepercentage;
1804 tc_precexp = fls(t + (t >> 1)) - 1;
1805 FREQ2BT(hz / tc_tick, &bt_timethreshold);
1806 FREQ2BT(hz, &bt_tickthreshold);
1807 bintime_shift(&bt_timethreshold, tc_precexp);
1808 bintime_shift(&bt_tickthreshold, tc_precexp);
1809 } else {
1810 tc_precexp = 31;
1811 bt_timethreshold.sec = INT_MAX;
1812 bt_timethreshold.frac = ~(uint64_t)0;
1813 bt_tickthreshold = bt_timethreshold;
1814 }
1815 sbt_timethreshold = bttosbt(bt_timethreshold);
1816 sbt_tickthreshold = bttosbt(bt_tickthreshold);
1817 }
1818
1819 static int
1820 sysctl_kern_timecounter_adjprecision(SYSCTL_HANDLER_ARGS)
1821 {
1822 int error, val;
1823
1824 val = tc_timepercentage;
1825 error = sysctl_handle_int(oidp, &val, 0, req);
1826 if (error != 0 || req->newptr == NULL)
1827 return (error);
1828 tc_timepercentage = val;
1829 tc_adjprecision();
1830 return (0);
1831 }
1832
1833 static void
1834 inittimecounter(void *dummy)
1835 {
1836 u_int p;
1837 int tick_rate;
1838
1839 /*
1840 * Set the initial timeout to
1841 * max(1, <approx. number of hardclock ticks in a millisecond>).
1842 * People should probably not use the sysctl to set the timeout
1843 * to smaller than its inital value, since that value is the
1844 * smallest reasonable one. If they want better timestamps they
1845 * should use the non-"get"* functions.
1846 */
1847 if (hz > 1000)
1848 tc_tick = (hz + 500) / 1000;
1849 else
1850 tc_tick = 1;
1851 tc_adjprecision();
1852 FREQ2BT(hz, &tick_bt);
1853 tick_sbt = bttosbt(tick_bt);
1854 tick_rate = hz / tc_tick;
1855 FREQ2BT(tick_rate, &tc_tick_bt);
1856 tc_tick_sbt = bttosbt(tc_tick_bt);
1857 p = (tc_tick * 1000000) / hz;
1858 printf("Timecounters tick every %d.%03u msec\n", p / 1000, p % 1000);
1859
1860 #ifdef FFCLOCK
1861 ffclock_init();
1862 #endif
1863 /* warm up new timecounter (again) and get rolling. */
1864 (void)timecounter->tc_get_timecount(timecounter);
1865 (void)timecounter->tc_get_timecount(timecounter);
1866 tc_windup();
1867 }
1868
1869 SYSINIT(timecounter, SI_SUB_CLOCKS, SI_ORDER_SECOND, inittimecounter, NULL);
1870
1871 /* Cpu tick handling -------------------------------------------------*/
1872
1873 static int cpu_tick_variable;
1874 static uint64_t cpu_tick_frequency;
1875
1876 static uint64_t
1877 tc_cpu_ticks(void)
1878 {
1879 static uint64_t base;
1880 static unsigned last;
1881 unsigned u;
1882 struct timecounter *tc;
1883
1884 tc = timehands->th_counter;
1885 u = tc->tc_get_timecount(tc) & tc->tc_counter_mask;
1886 if (u < last)
1887 base += (uint64_t)tc->tc_counter_mask + 1;
1888 last = u;
1889 return (u + base);
1890 }
1891
1892 void
1893 cpu_tick_calibration(void)
1894 {
1895 static time_t last_calib;
1896
1897 if (time_uptime != last_calib && !(time_uptime & 0xf)) {
1898 cpu_tick_calibrate(0);
1899 last_calib = time_uptime;
1900 }
1901 }
1902
1903 /*
1904 * This function gets called every 16 seconds on only one designated
1905 * CPU in the system from hardclock() via cpu_tick_calibration()().
1906 *
1907 * Whenever the real time clock is stepped we get called with reset=1
1908 * to make sure we handle suspend/resume and similar events correctly.
1909 */
1910
1911 static void
1912 cpu_tick_calibrate(int reset)
1913 {
1914 static uint64_t c_last;
1915 uint64_t c_this, c_delta;
1916 static struct bintime t_last;
1917 struct bintime t_this, t_delta;
1918 uint32_t divi;
1919
1920 if (reset) {
1921 /* The clock was stepped, abort & reset */
1922 t_last.sec = 0;
1923 return;
1924 }
1925
1926 /* we don't calibrate fixed rate cputicks */
1927 if (!cpu_tick_variable)
1928 return;
1929
1930 getbinuptime(&t_this);
1931 c_this = cpu_ticks();
1932 if (t_last.sec != 0) {
1933 c_delta = c_this - c_last;
1934 t_delta = t_this;
1935 bintime_sub(&t_delta, &t_last);
1936 /*
1937 * Headroom:
1938 * 2^(64-20) / 16[s] =
1939 * 2^(44) / 16[s] =
1940 * 17.592.186.044.416 / 16 =
1941 * 1.099.511.627.776 [Hz]
1942 */
1943 divi = t_delta.sec << 20;
1944 divi |= t_delta.frac >> (64 - 20);
1945 c_delta <<= 20;
1946 c_delta /= divi;
1947 if (c_delta > cpu_tick_frequency) {
1948 if (0 && bootverbose)
1949 printf("cpu_tick increased to %ju Hz\n",
1950 c_delta);
1951 cpu_tick_frequency = c_delta;
1952 }
1953 }
1954 c_last = c_this;
1955 t_last = t_this;
1956 }
1957
1958 void
1959 set_cputicker(cpu_tick_f *func, uint64_t freq, unsigned var)
1960 {
1961
1962 if (func == NULL) {
1963 cpu_ticks = tc_cpu_ticks;
1964 } else {
1965 cpu_tick_frequency = freq;
1966 cpu_tick_variable = var;
1967 cpu_ticks = func;
1968 }
1969 }
1970
1971 uint64_t
1972 cpu_tickrate(void)
1973 {
1974
1975 if (cpu_ticks == tc_cpu_ticks)
1976 return (tc_getfrequency());
1977 return (cpu_tick_frequency);
1978 }
1979
1980 /*
1981 * We need to be slightly careful converting cputicks to microseconds.
1982 * There is plenty of margin in 64 bits of microseconds (half a million
1983 * years) and in 64 bits at 4 GHz (146 years), but if we do a multiply
1984 * before divide conversion (to retain precision) we find that the
1985 * margin shrinks to 1.5 hours (one millionth of 146y).
1986 * With a three prong approach we never lose significant bits, no
1987 * matter what the cputick rate and length of timeinterval is.
1988 */
1989
1990 uint64_t
1991 cputick2usec(uint64_t tick)
1992 {
1993
1994 if (tick > 18446744073709551LL) /* floor(2^64 / 1000) */
1995 return (tick / (cpu_tickrate() / 1000000LL));
1996 else if (tick > 18446744073709LL) /* floor(2^64 / 1000000) */
1997 return ((tick * 1000LL) / (cpu_tickrate() / 1000LL));
1998 else
1999 return ((tick * 1000000LL) / cpu_tickrate());
2000 }
2001
2002 cpu_tick_f *cpu_ticks = tc_cpu_ticks;
2003
2004 static int vdso_th_enable = 1;
2005 static int
2006 sysctl_fast_gettime(SYSCTL_HANDLER_ARGS)
2007 {
2008 int old_vdso_th_enable, error;
2009
2010 old_vdso_th_enable = vdso_th_enable;
2011 error = sysctl_handle_int(oidp, &old_vdso_th_enable, 0, req);
2012 if (error != 0)
2013 return (error);
2014 vdso_th_enable = old_vdso_th_enable;
2015 timekeep_push_vdso();
2016 return (0);
2017 }
2018 SYSCTL_PROC(_kern_timecounter, OID_AUTO, fast_gettime,
2019 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
2020 NULL, 0, sysctl_fast_gettime, "I", "Enable fast time of day");
2021
2022 uint32_t
2023 tc_fill_vdso_timehands(struct vdso_timehands *vdso_th)
2024 {
2025 struct timehands *th;
2026 uint32_t enabled;
2027
2028 th = timehands;
2029 vdso_th->th_algo = VDSO_TH_ALGO_1;
2030 vdso_th->th_scale = th->th_scale;
2031 vdso_th->th_offset_count = th->th_offset_count;
2032 vdso_th->th_counter_mask = th->th_counter->tc_counter_mask;
2033 vdso_th->th_offset = th->th_offset;
2034 vdso_th->th_boottime = boottimebin;
2035 enabled = cpu_fill_vdso_timehands(vdso_th);
2036 if (!vdso_th_enable)
2037 enabled = 0;
2038 return (enabled);
2039 }
2040
2041 #ifdef COMPAT_FREEBSD32
2042 uint32_t
2043 tc_fill_vdso_timehands32(struct vdso_timehands32 *vdso_th32)
2044 {
2045 struct timehands *th;
2046 uint32_t enabled;
2047
2048 th = timehands;
2049 vdso_th32->th_algo = VDSO_TH_ALGO_1;
2050 *(uint64_t *)&vdso_th32->th_scale[0] = th->th_scale;
2051 vdso_th32->th_offset_count = th->th_offset_count;
2052 vdso_th32->th_counter_mask = th->th_counter->tc_counter_mask;
2053 vdso_th32->th_offset.sec = th->th_offset.sec;
2054 *(uint64_t *)&vdso_th32->th_offset.frac[0] = th->th_offset.frac;
2055 vdso_th32->th_boottime.sec = boottimebin.sec;
2056 *(uint64_t *)&vdso_th32->th_boottime.frac[0] = boottimebin.frac;
2057 enabled = cpu_fill_vdso_timehands32(vdso_th32);
2058 if (!vdso_th_enable)
2059 enabled = 0;
2060 return (enabled);
2061 }
2062 #endif
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