misc cleanup. Add a case where we don't want an idlethread to HLT (if there
[dragonfly.git] / sys / kern / kern_clock.c
CommitLineData
984263bc
MD
1/*-
2 * Copyright (c) 1997, 1998 Poul-Henning Kamp <phk@FreeBSD.org>
3 * Copyright (c) 1982, 1986, 1991, 1993
4 * The Regents of the University of California. All rights reserved.
5 * (c) UNIX System Laboratories, Inc.
6 * All or some portions of this file are derived from material licensed
7 * to the University of California by American Telephone and Telegraph
8 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
9 * the permission of UNIX System Laboratories, Inc.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * @(#)kern_clock.c 8.5 (Berkeley) 1/21/94
40 * $FreeBSD: src/sys/kern/kern_clock.c,v 1.105.2.10 2002/10/17 13:19:40 maxim Exp $
a2a5ad0d 41 * $DragonFly: src/sys/kern/kern_clock.c,v 1.7 2003/07/10 04:47:54 dillon Exp $
984263bc
MD
42 */
43
44#include "opt_ntp.h"
45
46#include <sys/param.h>
47#include <sys/systm.h>
48#include <sys/dkstat.h>
49#include <sys/callout.h>
50#include <sys/kernel.h>
51#include <sys/proc.h>
52#include <sys/malloc.h>
53#include <sys/resourcevar.h>
54#include <sys/signalvar.h>
55#include <sys/timex.h>
56#include <sys/timepps.h>
57#include <vm/vm.h>
58#include <sys/lock.h>
59#include <vm/pmap.h>
60#include <vm/vm_map.h>
61#include <sys/sysctl.h>
62
63#include <machine/cpu.h>
64#include <machine/limits.h>
65#include <machine/smp.h>
66
67#ifdef GPROF
68#include <sys/gmon.h>
69#endif
70
71#ifdef DEVICE_POLLING
72extern void init_device_poll(void);
73extern void hardclock_device_poll(void);
74#endif /* DEVICE_POLLING */
75
76/*
77 * Number of timecounters used to implement stable storage
78 */
79#ifndef NTIMECOUNTER
80#define NTIMECOUNTER 5
81#endif
82
83static MALLOC_DEFINE(M_TIMECOUNTER, "timecounter",
84 "Timecounter stable storage");
85
86static void initclocks __P((void *dummy));
87SYSINIT(clocks, SI_SUB_CLOCKS, SI_ORDER_FIRST, initclocks, NULL)
88
89static void tco_forward __P((int force));
90static void tco_setscales __P((struct timecounter *tc));
91static __inline unsigned tco_delta __P((struct timecounter *tc));
92
93/* Some of these don't belong here, but it's easiest to concentrate them. */
94long cp_time[CPUSTATES];
95
96SYSCTL_OPAQUE(_kern, OID_AUTO, cp_time, CTLFLAG_RD, &cp_time, sizeof(cp_time),
97 "LU", "CPU time statistics");
98
99long tk_cancc;
100long tk_nin;
101long tk_nout;
102long tk_rawcc;
103
104time_t time_second;
105
106struct timeval boottime;
107SYSCTL_STRUCT(_kern, KERN_BOOTTIME, boottime, CTLFLAG_RD,
108 &boottime, timeval, "System boottime");
109
110/*
111 * Which update policy to use.
112 * 0 - every tick, bad hardware may fail with "calcru negative..."
113 * 1 - more resistent to the above hardware, but less efficient.
114 */
115static int tco_method;
116
117/*
118 * Implement a dummy timecounter which we can use until we get a real one
119 * in the air. This allows the console and other early stuff to use
120 * timeservices.
121 */
122
123static unsigned
124dummy_get_timecount(struct timecounter *tc)
125{
126 static unsigned now;
127 return (++now);
128}
129
130static struct timecounter dummy_timecounter = {
131 dummy_get_timecount,
132 0,
133 ~0u,
134 1000000,
135 "dummy"
136};
137
138struct timecounter *timecounter = &dummy_timecounter;
139
140/*
141 * Clock handling routines.
142 *
143 * This code is written to operate with two timers that run independently of
144 * each other.
145 *
146 * The main timer, running hz times per second, is used to trigger interval
147 * timers, timeouts and rescheduling as needed.
148 *
149 * The second timer handles kernel and user profiling,
150 * and does resource use estimation. If the second timer is programmable,
151 * it is randomized to avoid aliasing between the two clocks. For example,
152 * the randomization prevents an adversary from always giving up the cpu
153 * just before its quantum expires. Otherwise, it would never accumulate
154 * cpu ticks. The mean frequency of the second timer is stathz.
155 *
156 * If no second timer exists, stathz will be zero; in this case we drive
157 * profiling and statistics off the main clock. This WILL NOT be accurate;
158 * do not do it unless absolutely necessary.
159 *
160 * The statistics clock may (or may not) be run at a higher rate while
161 * profiling. This profile clock runs at profhz. We require that profhz
162 * be an integral multiple of stathz.
163 *
164 * If the statistics clock is running fast, it must be divided by the ratio
165 * profhz/stathz for statistics. (For profiling, every tick counts.)
166 *
167 * Time-of-day is maintained using a "timecounter", which may or may
168 * not be related to the hardware generating the above mentioned
169 * interrupts.
170 */
171
172int stathz;
173int profhz;
174static int profprocs;
175int ticks;
176static int psdiv, pscnt; /* prof => stat divider */
177int psratio; /* ratio: prof / stat */
178
179/*
180 * Initialize clock frequencies and start both clocks running.
181 */
182/* ARGSUSED*/
183static void
184initclocks(dummy)
185 void *dummy;
186{
187 register int i;
188
189 /*
190 * Set divisors to 1 (normal case) and let the machine-specific
191 * code do its bit.
192 */
193 psdiv = pscnt = 1;
194 cpu_initclocks();
195
196#ifdef DEVICE_POLLING
197 init_device_poll();
198#endif
199
200 /*
201 * Compute profhz/stathz, and fix profhz if needed.
202 */
203 i = stathz ? stathz : hz;
204 if (profhz == 0)
205 profhz = i;
206 psratio = profhz / i;
207}
208
209/*
4b5f931b
MD
210 * The real-time timer, interrupting hz times per second. This is implemented
211 * as a FAST interrupt so it is in the context of the thread it interrupted,
212 * and not in an interrupt thread. YYY needs help.
984263bc
MD
213 */
214void
215hardclock(frame)
216 register struct clockframe *frame;
217{
218 register struct proc *p;
219
220 p = curproc;
221 if (p) {
222 register struct pstats *pstats;
223
224 /*
225 * Run current process's virtual and profile time, as needed.
226 */
227 pstats = p->p_stats;
228 if (CLKF_USERMODE(frame) &&
229 timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value) &&
230 itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], tick) == 0)
231 psignal(p, SIGVTALRM);
232 if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value) &&
233 itimerdecr(&pstats->p_timer[ITIMER_PROF], tick) == 0)
234 psignal(p, SIGPROF);
235 }
236
237#if defined(SMP) && defined(BETTER_CLOCK)
238 forward_hardclock(pscnt);
239#endif
240
241 /*
242 * If no separate statistics clock is available, run it from here.
243 */
244 if (stathz == 0)
245 statclock(frame);
246
247 tco_forward(0);
248 ticks++;
249
250#ifdef DEVICE_POLLING
251 hardclock_device_poll(); /* this is very short and quick */
252#endif /* DEVICE_POLLING */
253
254 /*
255 * Process callouts at a very low cpu priority, so we don't keep the
256 * relatively high clock interrupt priority any longer than necessary.
257 */
258 if (TAILQ_FIRST(&callwheel[ticks & callwheelmask]) != NULL) {
b68b7282
MD
259 setsoftclock();
260 } else if (softticks + 1 == ticks) {
984263bc 261 ++softticks;
b68b7282 262 }
984263bc
MD
263}
264
265/*
266 * Compute number of ticks in the specified amount of time.
267 */
268int
269tvtohz(tv)
270 struct timeval *tv;
271{
272 register unsigned long ticks;
273 register long sec, usec;
274
275 /*
276 * If the number of usecs in the whole seconds part of the time
277 * difference fits in a long, then the total number of usecs will
278 * fit in an unsigned long. Compute the total and convert it to
279 * ticks, rounding up and adding 1 to allow for the current tick
280 * to expire. Rounding also depends on unsigned long arithmetic
281 * to avoid overflow.
282 *
283 * Otherwise, if the number of ticks in the whole seconds part of
284 * the time difference fits in a long, then convert the parts to
285 * ticks separately and add, using similar rounding methods and
286 * overflow avoidance. This method would work in the previous
287 * case but it is slightly slower and assumes that hz is integral.
288 *
289 * Otherwise, round the time difference down to the maximum
290 * representable value.
291 *
292 * If ints have 32 bits, then the maximum value for any timeout in
293 * 10ms ticks is 248 days.
294 */
295 sec = tv->tv_sec;
296 usec = tv->tv_usec;
297 if (usec < 0) {
298 sec--;
299 usec += 1000000;
300 }
301 if (sec < 0) {
302#ifdef DIAGNOSTIC
303 if (usec > 0) {
304 sec++;
305 usec -= 1000000;
306 }
307 printf("tvotohz: negative time difference %ld sec %ld usec\n",
308 sec, usec);
309#endif
310 ticks = 1;
311 } else if (sec <= LONG_MAX / 1000000)
312 ticks = (sec * 1000000 + (unsigned long)usec + (tick - 1))
313 / tick + 1;
314 else if (sec <= LONG_MAX / hz)
315 ticks = sec * hz
316 + ((unsigned long)usec + (tick - 1)) / tick + 1;
317 else
318 ticks = LONG_MAX;
319 if (ticks > INT_MAX)
320 ticks = INT_MAX;
321 return ((int)ticks);
322}
323
324/*
325 * Start profiling on a process.
326 *
327 * Kernel profiling passes proc0 which never exits and hence
328 * keeps the profile clock running constantly.
329 */
330void
331startprofclock(p)
332 register struct proc *p;
333{
334 int s;
335
336 if ((p->p_flag & P_PROFIL) == 0) {
337 p->p_flag |= P_PROFIL;
338 if (++profprocs == 1 && stathz != 0) {
339 s = splstatclock();
340 psdiv = pscnt = psratio;
341 setstatclockrate(profhz);
342 splx(s);
343 }
344 }
345}
346
347/*
348 * Stop profiling on a process.
349 */
350void
351stopprofclock(p)
352 register struct proc *p;
353{
354 int s;
355
356 if (p->p_flag & P_PROFIL) {
357 p->p_flag &= ~P_PROFIL;
358 if (--profprocs == 0 && stathz != 0) {
359 s = splstatclock();
360 psdiv = pscnt = 1;
361 setstatclockrate(stathz);
362 splx(s);
363 }
364 }
365}
366
367/*
368 * Statistics clock. Grab profile sample, and if divider reaches 0,
369 * do process and kernel statistics. Most of the statistics are only
370 * used by user-level statistics programs. The main exceptions are
371 * p->p_uticks, p->p_sticks, p->p_iticks, and p->p_estcpu.
4b5f931b
MD
372 *
373 * The statclock should be called from an exclusive, fast interrupt,
374 * so the context should be the thread/process that got interrupted and
375 * not an interrupt thread.
984263bc
MD
376 */
377void
378statclock(frame)
379 register struct clockframe *frame;
380{
381#ifdef GPROF
382 register struct gmonparam *g;
383 int i;
384#endif
d16a8831 385 thread_t td;
984263bc
MD
386 struct pstats *pstats;
387 long rss;
388 struct rusage *ru;
389 struct vmspace *vm;
d16a8831
MD
390 struct proc *p;
391 int bump;
392 struct timeval tv;
393 struct timeval *stv;
984263bc 394
d16a8831
MD
395 /*
396 * How big was our timeslice relative to the last time
397 */
398 microuptime(&tv);
399 stv = &mycpu->gd_stattv;
400 if (stv->tv_sec == 0) {
401 bump = 1;
402 } else {
403 bump = tv.tv_usec - stv->tv_usec +
404 (tv.tv_sec - stv->tv_sec) * 1000000;
405 if (bump < 0)
406 bump = 0;
407 if (bump > 1000000)
408 bump = 1000000;
409 }
410 *stv = tv;
411
412 td = curthread;
413 p = td->td_proc;
414
415 if (CLKF_USERMODE(frame)) {
984263bc 416 /*
d16a8831
MD
417 * Came from userland, handle user time and deal with
418 * possible process.
984263bc 419 */
d16a8831 420 if (p && (p->p_flag & P_PROFIL))
984263bc
MD
421 addupc_intr(p, CLKF_PC(frame), 1);
422#if defined(SMP) && defined(BETTER_CLOCK)
423 if (stathz != 0)
424 forward_statclock(pscnt);
425#endif
d16a8831 426 td->td_uticks += bump;
984263bc
MD
427 if (--pscnt > 0)
428 return;
d16a8831 429
984263bc 430 /*
d16a8831 431 * Charge the time as appropriate
984263bc 432 */
d16a8831
MD
433 if (p && p->p_nice > NZERO)
434 ++cp_time[CP_NICE];
984263bc 435 else
d16a8831 436 ++cp_time[CP_USER];
984263bc
MD
437 } else {
438#ifdef GPROF
439 /*
440 * Kernel statistics are just like addupc_intr, only easier.
441 */
442 g = &_gmonparam;
443 if (g->state == GMON_PROF_ON) {
444 i = CLKF_PC(frame) - g->lowpc;
445 if (i < g->textsize) {
446 i /= HISTFRACTION * sizeof(*g->kcount);
447 g->kcount[i]++;
448 }
449 }
450#endif
451#if defined(SMP) && defined(BETTER_CLOCK)
452 if (stathz != 0)
453 forward_statclock(pscnt);
454#endif
984263bc
MD
455 /*
456 * Came from kernel mode, so we were:
457 * - handling an interrupt,
458 * - doing syscall or trap work on behalf of the current
459 * user process, or
460 * - spinning in the idle loop.
461 * Whichever it is, charge the time as appropriate.
462 * Note that we charge interrupts to the current process,
463 * regardless of whether they are ``for'' that process,
464 * so that we know how much of its real time was spent
465 * in ``non-process'' (i.e., interrupt) work.
466 */
d16a8831
MD
467 if (CLKF_INTR(frame))
468 td->td_iticks += bump;
469 else
470 td->td_sticks += bump;
471
472 if (--pscnt > 0)
473 return;
474
984263bc 475 if (CLKF_INTR(frame)) {
984263bc 476 cp_time[CP_INTR]++;
d16a8831 477 } else {
a2a5ad0d 478 if (td == &mycpu->gd_idlethread)
d16a8831
MD
479 ++cp_time[CP_IDLE];
480 else
481 ++cp_time[CP_SYS];
482 }
984263bc
MD
483 }
484 pscnt = psdiv;
485
486 if (p != NULL) {
487 schedclock(p);
488
489 /* Update resource usage integrals and maximums. */
490 if ((pstats = p->p_stats) != NULL &&
491 (ru = &pstats->p_ru) != NULL &&
492 (vm = p->p_vmspace) != NULL) {
493 ru->ru_ixrss += pgtok(vm->vm_tsize);
494 ru->ru_idrss += pgtok(vm->vm_dsize);
495 ru->ru_isrss += pgtok(vm->vm_ssize);
496 rss = pgtok(vmspace_resident_count(vm));
497 if (ru->ru_maxrss < rss)
498 ru->ru_maxrss = rss;
499 }
500 }
501}
502
503/*
504 * Return information about system clocks.
505 */
506static int
507sysctl_kern_clockrate(SYSCTL_HANDLER_ARGS)
508{
509 struct clockinfo clkinfo;
510 /*
511 * Construct clockinfo structure.
512 */
513 clkinfo.hz = hz;
514 clkinfo.tick = tick;
515 clkinfo.tickadj = tickadj;
516 clkinfo.profhz = profhz;
517 clkinfo.stathz = stathz ? stathz : hz;
518 return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req));
519}
520
521SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, CTLTYPE_STRUCT|CTLFLAG_RD,
522 0, 0, sysctl_kern_clockrate, "S,clockinfo","");
523
524static __inline unsigned
525tco_delta(struct timecounter *tc)
526{
527
528 return ((tc->tc_get_timecount(tc) - tc->tc_offset_count) &
529 tc->tc_counter_mask);
530}
531
532/*
533 * We have eight functions for looking at the clock, four for
534 * microseconds and four for nanoseconds. For each there is fast
535 * but less precise version "get{nano|micro}[up]time" which will
536 * return a time which is up to 1/HZ previous to the call, whereas
537 * the raw version "{nano|micro}[up]time" will return a timestamp
538 * which is as precise as possible. The "up" variants return the
539 * time relative to system boot, these are well suited for time
540 * interval measurements.
541 */
542
543void
544getmicrotime(struct timeval *tvp)
545{
546 struct timecounter *tc;
547
548 if (!tco_method) {
549 tc = timecounter;
550 *tvp = tc->tc_microtime;
551 } else {
552 microtime(tvp);
553 }
554}
555
556void
557getnanotime(struct timespec *tsp)
558{
559 struct timecounter *tc;
560
561 if (!tco_method) {
562 tc = timecounter;
563 *tsp = tc->tc_nanotime;
564 } else {
565 nanotime(tsp);
566 }
567}
568
569void
570microtime(struct timeval *tv)
571{
572 struct timecounter *tc;
573
574 tc = timecounter;
575 tv->tv_sec = tc->tc_offset_sec;
576 tv->tv_usec = tc->tc_offset_micro;
577 tv->tv_usec += ((u_int64_t)tco_delta(tc) * tc->tc_scale_micro) >> 32;
578 tv->tv_usec += boottime.tv_usec;
579 tv->tv_sec += boottime.tv_sec;
580 while (tv->tv_usec < 0) {
581 tv->tv_usec += 1000000;
582 if (tv->tv_sec > 0)
583 tv->tv_sec--;
584 }
585 while (tv->tv_usec >= 1000000) {
586 tv->tv_usec -= 1000000;
587 tv->tv_sec++;
588 }
589}
590
591void
592nanotime(struct timespec *ts)
593{
594 unsigned count;
595 u_int64_t delta;
596 struct timecounter *tc;
597
598 tc = timecounter;
599 ts->tv_sec = tc->tc_offset_sec;
600 count = tco_delta(tc);
601 delta = tc->tc_offset_nano;
602 delta += ((u_int64_t)count * tc->tc_scale_nano_f);
603 delta >>= 32;
604 delta += ((u_int64_t)count * tc->tc_scale_nano_i);
605 delta += boottime.tv_usec * 1000;
606 ts->tv_sec += boottime.tv_sec;
607 while (delta < 0) {
608 delta += 1000000000;
609 if (ts->tv_sec > 0)
610 ts->tv_sec--;
611 }
612 while (delta >= 1000000000) {
613 delta -= 1000000000;
614 ts->tv_sec++;
615 }
616 ts->tv_nsec = delta;
617}
618
619void
620getmicrouptime(struct timeval *tvp)
621{
622 struct timecounter *tc;
623
624 if (!tco_method) {
625 tc = timecounter;
626 tvp->tv_sec = tc->tc_offset_sec;
627 tvp->tv_usec = tc->tc_offset_micro;
628 } else {
629 microuptime(tvp);
630 }
631}
632
633void
634getnanouptime(struct timespec *tsp)
635{
636 struct timecounter *tc;
637
638 if (!tco_method) {
639 tc = timecounter;
640 tsp->tv_sec = tc->tc_offset_sec;
641 tsp->tv_nsec = tc->tc_offset_nano >> 32;
642 } else {
643 nanouptime(tsp);
644 }
645}
646
647void
648microuptime(struct timeval *tv)
649{
650 struct timecounter *tc;
651
652 tc = timecounter;
653 tv->tv_sec = tc->tc_offset_sec;
654 tv->tv_usec = tc->tc_offset_micro;
655 tv->tv_usec += ((u_int64_t)tco_delta(tc) * tc->tc_scale_micro) >> 32;
656 while (tv->tv_usec < 0) {
657 tv->tv_usec += 1000000;
658 if (tv->tv_sec > 0)
659 tv->tv_sec--;
660 }
661 while (tv->tv_usec >= 1000000) {
662 tv->tv_usec -= 1000000;
663 tv->tv_sec++;
664 }
665}
666
667void
668nanouptime(struct timespec *ts)
669{
670 unsigned count;
671 u_int64_t delta;
672 struct timecounter *tc;
673
674 tc = timecounter;
675 ts->tv_sec = tc->tc_offset_sec;
676 count = tco_delta(tc);
677 delta = tc->tc_offset_nano;
678 delta += ((u_int64_t)count * tc->tc_scale_nano_f);
679 delta >>= 32;
680 delta += ((u_int64_t)count * tc->tc_scale_nano_i);
681 while (delta < 0) {
682 delta += 1000000000;
683 if (ts->tv_sec > 0)
684 ts->tv_sec--;
685 }
686 while (delta >= 1000000000) {
687 delta -= 1000000000;
688 ts->tv_sec++;
689 }
690 ts->tv_nsec = delta;
691}
692
693static void
694tco_setscales(struct timecounter *tc)
695{
696 u_int64_t scale;
697
698 scale = 1000000000LL << 32;
699 scale += tc->tc_adjustment;
700 scale /= tc->tc_tweak->tc_frequency;
701 tc->tc_scale_micro = scale / 1000;
702 tc->tc_scale_nano_f = scale & 0xffffffff;
703 tc->tc_scale_nano_i = scale >> 32;
704}
705
706void
707update_timecounter(struct timecounter *tc)
708{
709 tco_setscales(tc);
710}
711
712void
713init_timecounter(struct timecounter *tc)
714{
715 struct timespec ts1;
716 struct timecounter *t1, *t2, *t3;
717 unsigned u;
718 int i;
719
720 u = tc->tc_frequency / tc->tc_counter_mask;
721 if (u > hz) {
722 printf("Timecounter \"%s\" frequency %lu Hz"
723 " -- Insufficient hz, needs at least %u\n",
724 tc->tc_name, (u_long) tc->tc_frequency, u);
725 return;
726 }
727
728 tc->tc_adjustment = 0;
729 tc->tc_tweak = tc;
730 tco_setscales(tc);
731 tc->tc_offset_count = tc->tc_get_timecount(tc);
732 if (timecounter == &dummy_timecounter)
733 tc->tc_avail = tc;
734 else {
735 tc->tc_avail = timecounter->tc_tweak->tc_avail;
736 timecounter->tc_tweak->tc_avail = tc;
737 }
738 MALLOC(t1, struct timecounter *, sizeof *t1, M_TIMECOUNTER, M_WAITOK);
739 tc->tc_other = t1;
740 *t1 = *tc;
741 t2 = t1;
742 for (i = 1; i < NTIMECOUNTER; i++) {
743 MALLOC(t3, struct timecounter *, sizeof *t3,
744 M_TIMECOUNTER, M_WAITOK);
745 *t3 = *tc;
746 t3->tc_other = t2;
747 t2 = t3;
748 }
749 t1->tc_other = t3;
750 tc = t1;
751
752 printf("Timecounter \"%s\" frequency %lu Hz\n",
753 tc->tc_name, (u_long)tc->tc_frequency);
754
755 /* XXX: For now always start using the counter. */
756 tc->tc_offset_count = tc->tc_get_timecount(tc);
757 nanouptime(&ts1);
758 tc->tc_offset_nano = (u_int64_t)ts1.tv_nsec << 32;
759 tc->tc_offset_micro = ts1.tv_nsec / 1000;
760 tc->tc_offset_sec = ts1.tv_sec;
761 timecounter = tc;
762}
763
764void
765set_timecounter(struct timespec *ts)
766{
767 struct timespec ts2;
768
769 nanouptime(&ts2);
770 boottime.tv_sec = ts->tv_sec - ts2.tv_sec;
771 boottime.tv_usec = (ts->tv_nsec - ts2.tv_nsec) / 1000;
772 if (boottime.tv_usec < 0) {
773 boottime.tv_usec += 1000000;
774 boottime.tv_sec--;
775 }
776 /* fiddle all the little crinkly bits around the fiords... */
777 tco_forward(1);
778}
779
780static void
781switch_timecounter(struct timecounter *newtc)
782{
783 int s;
784 struct timecounter *tc;
785 struct timespec ts;
786
787 s = splclock();
788 tc = timecounter;
789 if (newtc->tc_tweak == tc->tc_tweak) {
790 splx(s);
791 return;
792 }
793 newtc = newtc->tc_tweak->tc_other;
794 nanouptime(&ts);
795 newtc->tc_offset_sec = ts.tv_sec;
796 newtc->tc_offset_nano = (u_int64_t)ts.tv_nsec << 32;
797 newtc->tc_offset_micro = ts.tv_nsec / 1000;
798 newtc->tc_offset_count = newtc->tc_get_timecount(newtc);
799 tco_setscales(newtc);
800 timecounter = newtc;
801 splx(s);
802}
803
804static struct timecounter *
805sync_other_counter(void)
806{
807 struct timecounter *tc, *tcn, *tco;
808 unsigned delta;
809
810 tco = timecounter;
811 tc = tco->tc_other;
812 tcn = tc->tc_other;
813 *tc = *tco;
814 tc->tc_other = tcn;
815 delta = tco_delta(tc);
816 tc->tc_offset_count += delta;
817 tc->tc_offset_count &= tc->tc_counter_mask;
818 tc->tc_offset_nano += (u_int64_t)delta * tc->tc_scale_nano_f;
819 tc->tc_offset_nano += (u_int64_t)delta * tc->tc_scale_nano_i << 32;
820 return (tc);
821}
822
823static void
824tco_forward(int force)
825{
826 struct timecounter *tc, *tco;
827 struct timeval tvt;
828
829 tco = timecounter;
830 tc = sync_other_counter();
831 /*
832 * We may be inducing a tiny error here, the tc_poll_pps() may
833 * process a latched count which happens after the tco_delta()
834 * in sync_other_counter(), which would extend the previous
835 * counters parameters into the domain of this new one.
836 * Since the timewindow is very small for this, the error is
837 * going to be only a few weenieseconds (as Dave Mills would
838 * say), so lets just not talk more about it, OK ?
839 */
840 if (tco->tc_poll_pps)
841 tco->tc_poll_pps(tco);
842 if (timedelta != 0) {
843 tvt = boottime;
844 tvt.tv_usec += tickdelta;
845 if (tvt.tv_usec >= 1000000) {
846 tvt.tv_sec++;
847 tvt.tv_usec -= 1000000;
848 } else if (tvt.tv_usec < 0) {
849 tvt.tv_sec--;
850 tvt.tv_usec += 1000000;
851 }
852 boottime = tvt;
853 timedelta -= tickdelta;
854 }
855
856 while (tc->tc_offset_nano >= 1000000000ULL << 32) {
857 tc->tc_offset_nano -= 1000000000ULL << 32;
858 tc->tc_offset_sec++;
859 ntp_update_second(tc); /* XXX only needed if xntpd runs */
860 tco_setscales(tc);
861 force++;
862 }
863
864 if (tco_method && !force)
865 return;
866
867 tc->tc_offset_micro = (tc->tc_offset_nano / 1000) >> 32;
868
869 /* Figure out the wall-clock time */
870 tc->tc_nanotime.tv_sec = tc->tc_offset_sec + boottime.tv_sec;
871 tc->tc_nanotime.tv_nsec =
872 (tc->tc_offset_nano >> 32) + boottime.tv_usec * 1000;
873 tc->tc_microtime.tv_usec = tc->tc_offset_micro + boottime.tv_usec;
874 while (tc->tc_nanotime.tv_nsec >= 1000000000) {
875 tc->tc_nanotime.tv_nsec -= 1000000000;
876 tc->tc_microtime.tv_usec -= 1000000;
877 tc->tc_nanotime.tv_sec++;
878 }
879 time_second = tc->tc_microtime.tv_sec = tc->tc_nanotime.tv_sec;
880
881 timecounter = tc;
882}
883
884SYSCTL_NODE(_kern, OID_AUTO, timecounter, CTLFLAG_RW, 0, "");
885
886SYSCTL_INT(_kern_timecounter, OID_AUTO, method, CTLFLAG_RW, &tco_method, 0,
887 "This variable determines the method used for updating timecounters. "
888 "If the default algorithm (0) fails with \"calcru negative...\" messages "
889 "try the alternate algorithm (1) which handles bad hardware better."
890
891);
892
893static int
894sysctl_kern_timecounter_hardware(SYSCTL_HANDLER_ARGS)
895{
896 char newname[32];
897 struct timecounter *newtc, *tc;
898 int error;
899
900 tc = timecounter->tc_tweak;
901 strncpy(newname, tc->tc_name, sizeof(newname));
902 error = sysctl_handle_string(oidp, &newname[0], sizeof(newname), req);
903 if (error == 0 && req->newptr != NULL &&
904 strcmp(newname, tc->tc_name) != 0) {
905 for (newtc = tc->tc_avail; newtc != tc;
906 newtc = newtc->tc_avail) {
907 if (strcmp(newname, newtc->tc_name) == 0) {
908 /* Warm up new timecounter. */
909 (void)newtc->tc_get_timecount(newtc);
910
911 switch_timecounter(newtc);
912 return (0);
913 }
914 }
915 return (EINVAL);
916 }
917 return (error);
918}
919
920SYSCTL_PROC(_kern_timecounter, OID_AUTO, hardware, CTLTYPE_STRING | CTLFLAG_RW,
921 0, 0, sysctl_kern_timecounter_hardware, "A", "");
922
923
924int
925pps_ioctl(u_long cmd, caddr_t data, struct pps_state *pps)
926{
927 pps_params_t *app;
928 struct pps_fetch_args *fapi;
929#ifdef PPS_SYNC
930 struct pps_kcbind_args *kapi;
931#endif
932
933 switch (cmd) {
934 case PPS_IOC_CREATE:
935 return (0);
936 case PPS_IOC_DESTROY:
937 return (0);
938 case PPS_IOC_SETPARAMS:
939 app = (pps_params_t *)data;
940 if (app->mode & ~pps->ppscap)
941 return (EINVAL);
942 pps->ppsparam = *app;
943 return (0);
944 case PPS_IOC_GETPARAMS:
945 app = (pps_params_t *)data;
946 *app = pps->ppsparam;
947 app->api_version = PPS_API_VERS_1;
948 return (0);
949 case PPS_IOC_GETCAP:
950 *(int*)data = pps->ppscap;
951 return (0);
952 case PPS_IOC_FETCH:
953 fapi = (struct pps_fetch_args *)data;
954 if (fapi->tsformat && fapi->tsformat != PPS_TSFMT_TSPEC)
955 return (EINVAL);
956 if (fapi->timeout.tv_sec || fapi->timeout.tv_nsec)
957 return (EOPNOTSUPP);
958 pps->ppsinfo.current_mode = pps->ppsparam.mode;
959 fapi->pps_info_buf = pps->ppsinfo;
960 return (0);
961 case PPS_IOC_KCBIND:
962#ifdef PPS_SYNC
963 kapi = (struct pps_kcbind_args *)data;
964 /* XXX Only root should be able to do this */
965 if (kapi->tsformat && kapi->tsformat != PPS_TSFMT_TSPEC)
966 return (EINVAL);
967 if (kapi->kernel_consumer != PPS_KC_HARDPPS)
968 return (EINVAL);
969 if (kapi->edge & ~pps->ppscap)
970 return (EINVAL);
971 pps->kcmode = kapi->edge;
972 return (0);
973#else
974 return (EOPNOTSUPP);
975#endif
976 default:
977 return (ENOTTY);
978 }
979}
980
981void
982pps_init(struct pps_state *pps)
983{
984 pps->ppscap |= PPS_TSFMT_TSPEC;
985 if (pps->ppscap & PPS_CAPTUREASSERT)
986 pps->ppscap |= PPS_OFFSETASSERT;
987 if (pps->ppscap & PPS_CAPTURECLEAR)
988 pps->ppscap |= PPS_OFFSETCLEAR;
989}
990
991void
992pps_event(struct pps_state *pps, struct timecounter *tc, unsigned count, int event)
993{
994 struct timespec ts, *tsp, *osp;
995 u_int64_t delta;
996 unsigned tcount, *pcount;
997 int foff, fhard;
998 pps_seq_t *pseq;
999
1000 /* Things would be easier with arrays... */
1001 if (event == PPS_CAPTUREASSERT) {
1002 tsp = &pps->ppsinfo.assert_timestamp;
1003 osp = &pps->ppsparam.assert_offset;
1004 foff = pps->ppsparam.mode & PPS_OFFSETASSERT;
1005 fhard = pps->kcmode & PPS_CAPTUREASSERT;
1006 pcount = &pps->ppscount[0];
1007 pseq = &pps->ppsinfo.assert_sequence;
1008 } else {
1009 tsp = &pps->ppsinfo.clear_timestamp;
1010 osp = &pps->ppsparam.clear_offset;
1011 foff = pps->ppsparam.mode & PPS_OFFSETCLEAR;
1012 fhard = pps->kcmode & PPS_CAPTURECLEAR;
1013 pcount = &pps->ppscount[1];
1014 pseq = &pps->ppsinfo.clear_sequence;
1015 }
1016
1017 /* The timecounter changed: bail */
1018 if (!pps->ppstc ||
1019 pps->ppstc->tc_name != tc->tc_name ||
1020 tc->tc_name != timecounter->tc_name) {
1021 pps->ppstc = tc;
1022 *pcount = count;
1023 return;
1024 }
1025
1026 /* Nothing really happened */
1027 if (*pcount == count)
1028 return;
1029
1030 *pcount = count;
1031
1032 /* Convert the count to timespec */
1033 ts.tv_sec = tc->tc_offset_sec;
1034 tcount = count - tc->tc_offset_count;
1035 tcount &= tc->tc_counter_mask;
1036 delta = tc->tc_offset_nano;
1037 delta += ((u_int64_t)tcount * tc->tc_scale_nano_f);
1038 delta >>= 32;
1039 delta += ((u_int64_t)tcount * tc->tc_scale_nano_i);
1040 delta += boottime.tv_usec * 1000;
1041 ts.tv_sec += boottime.tv_sec;
1042 while (delta >= 1000000000) {
1043 delta -= 1000000000;
1044 ts.tv_sec++;
1045 }
1046 ts.tv_nsec = delta;
1047
1048 (*pseq)++;
1049 *tsp = ts;
1050
1051 if (foff) {
1052 timespecadd(tsp, osp);
1053 if (tsp->tv_nsec < 0) {
1054 tsp->tv_nsec += 1000000000;
1055 tsp->tv_sec -= 1;
1056 }
1057 }
1058#ifdef PPS_SYNC
1059 if (fhard) {
1060 /* magic, at its best... */
1061 tcount = count - pps->ppscount[2];
1062 pps->ppscount[2] = count;
1063 tcount &= tc->tc_counter_mask;
1064 delta = ((u_int64_t)tcount * tc->tc_tweak->tc_scale_nano_f);
1065 delta >>= 32;
1066 delta += ((u_int64_t)tcount * tc->tc_tweak->tc_scale_nano_i);
1067 hardpps(tsp, delta);
1068 }
1069#endif
1070}