xref: /dragonfly/sys/kern/kern_clock.c (revision 17b61719)
1 /*
2  * Copyright (c) 2003,2004 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * Copyright (c) 1997, 1998 Poul-Henning Kamp <phk@FreeBSD.org>
35  * Copyright (c) 1982, 1986, 1991, 1993
36  *	The Regents of the University of California.  All rights reserved.
37  * (c) UNIX System Laboratories, Inc.
38  * All or some portions of this file are derived from material licensed
39  * to the University of California by American Telephone and Telegraph
40  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
41  * the permission of UNIX System Laboratories, Inc.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. All advertising materials mentioning features or use of this software
52  *    must display the following acknowledgement:
53  *	This product includes software developed by the University of
54  *	California, Berkeley and its contributors.
55  * 4. Neither the name of the University nor the names of its contributors
56  *    may be used to endorse or promote products derived from this software
57  *    without specific prior written permission.
58  *
59  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
60  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
61  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
62  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
63  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
64  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
65  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
66  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
67  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
68  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
69  * SUCH DAMAGE.
70  *
71  *	@(#)kern_clock.c	8.5 (Berkeley) 1/21/94
72  * $FreeBSD: src/sys/kern/kern_clock.c,v 1.105.2.10 2002/10/17 13:19:40 maxim Exp $
73  * $DragonFly: src/sys/kern/kern_clock.c,v 1.23 2004/08/02 23:20:30 dillon Exp $
74  */
75 
76 #include "opt_ntp.h"
77 
78 #include <sys/param.h>
79 #include <sys/systm.h>
80 #include <sys/dkstat.h>
81 #include <sys/callout.h>
82 #include <sys/kernel.h>
83 #include <sys/proc.h>
84 #include <sys/malloc.h>
85 #include <sys/resourcevar.h>
86 #include <sys/signalvar.h>
87 #include <sys/timex.h>
88 #include <sys/timepps.h>
89 #include <vm/vm.h>
90 #include <sys/lock.h>
91 #include <vm/pmap.h>
92 #include <vm/vm_map.h>
93 #include <sys/sysctl.h>
94 #include <sys/thread2.h>
95 
96 #include <machine/cpu.h>
97 #include <machine/limits.h>
98 #include <machine/smp.h>
99 
100 #ifdef GPROF
101 #include <sys/gmon.h>
102 #endif
103 
104 #ifdef DEVICE_POLLING
105 extern void init_device_poll(void);
106 extern void hardclock_device_poll(void);
107 #endif /* DEVICE_POLLING */
108 
109 static void initclocks (void *dummy);
110 SYSINIT(clocks, SI_SUB_CLOCKS, SI_ORDER_FIRST, initclocks, NULL)
111 
112 /*
113  * Some of these don't belong here, but it's easiest to concentrate them.
114  * Note that cp_time[] counts in microseconds, but most userland programs
115  * just compare relative times against the total by delta.
116  */
117 long cp_time[CPUSTATES];
118 
119 SYSCTL_OPAQUE(_kern, OID_AUTO, cp_time, CTLFLAG_RD, &cp_time, sizeof(cp_time),
120     "LU", "CPU time statistics");
121 
122 long tk_cancc;
123 long tk_nin;
124 long tk_nout;
125 long tk_rawcc;
126 
127 /*
128  * boottime is used to calculate the 'real' uptime.  Do not confuse this with
129  * microuptime().  microtime() is not drift compensated.  The real uptime
130  * with compensation is nanotime() - bootime.  boottime is recalculated
131  * whenever the real time is set based on the compensated elapsed time
132  * in seconds (gd->gd_time_seconds).
133  *
134  * basetime is used to calculate the compensated real time of day.  Chunky
135  * changes to the time, aka settimeofday(), are made by modifying basetime.
136  *
137  * The gd_time_seconds and gd_cpuclock_base fields remain fairly monotonic.
138  * Slight adjustments to gd_cpuclock_base are made to phase-lock it to
139  * the real time.
140  */
141 struct timespec boottime;	/* boot time (realtime) for reference only */
142 struct timespec basetime;	/* base time adjusts uptime -> realtime */
143 time_t time_second;		/* read-only 'passive' uptime in seconds */
144 
145 SYSCTL_STRUCT(_kern, KERN_BOOTTIME, boottime, CTLFLAG_RD,
146     &boottime, timeval, "System boottime");
147 SYSCTL_STRUCT(_kern, OID_AUTO, basetime, CTLFLAG_RD,
148     &basetime, timeval, "System basetime");
149 
150 static void hardclock(systimer_t info, struct intrframe *frame);
151 static void statclock(systimer_t info, struct intrframe *frame);
152 static void schedclock(systimer_t info, struct intrframe *frame);
153 
154 int	ticks;			/* system master ticks at hz */
155 int	clocks_running;		/* tsleep/timeout clocks operational */
156 int64_t	nsec_adj;		/* ntpd per-tick adjustment in nsec << 32 */
157 int64_t	nsec_acc;		/* accumulator */
158 
159 /*
160  * Finish initializing clock frequencies and start all clocks running.
161  */
162 /* ARGSUSED*/
163 static void
164 initclocks(void *dummy)
165 {
166 	cpu_initclocks();
167 #ifdef DEVICE_POLLING
168 	init_device_poll();
169 #endif
170 	/*psratio = profhz / stathz;*/
171 	initclocks_pcpu();
172 	clocks_running = 1;
173 }
174 
175 /*
176  * Called on a per-cpu basis
177  */
178 void
179 initclocks_pcpu(void)
180 {
181 	struct globaldata *gd = mycpu;
182 
183 	crit_enter();
184 	if (gd->gd_cpuid == 0) {
185 	    gd->gd_time_seconds = 1;
186 	    gd->gd_cpuclock_base = cputimer_count();
187 	} else {
188 	    /* XXX */
189 	    gd->gd_time_seconds = globaldata_find(0)->gd_time_seconds;
190 	    gd->gd_cpuclock_base = globaldata_find(0)->gd_cpuclock_base;
191 	}
192 	systimer_init_periodic(&gd->gd_hardclock, hardclock, NULL, hz);
193 	systimer_init_periodic(&gd->gd_statclock, statclock, NULL, stathz);
194 	/* XXX correct the frequency for scheduler / estcpu tests */
195 	systimer_init_periodic(&gd->gd_schedclock, schedclock,
196 				NULL, ESTCPUFREQ);
197 	crit_exit();
198 }
199 
200 /*
201  * Resynchronize gd_cpuclock_base after the system has been woken up from
202  * a sleep.  It is absolutely essential that all the cpus be properly
203  * synchronized.  Resynching is required because nanouptime() and friends
204  * will overflow intermediate multiplications if more then 2 seconds
205  * worth of cputimer_cont() delta has built up.
206  */
207 #ifdef SMP
208 
209 static
210 void
211 restoreclocks_remote(lwkt_cpusync_t poll)
212 {
213 	mycpu->gd_cpuclock_base = *(sysclock_t *)poll->cs_data;
214 	mycpu->gd_time_seconds = globaldata_find(0)->gd_time_seconds;
215 }
216 
217 #endif
218 
219 void
220 restoreclocks(void)
221 {
222 	sysclock_t base = cputimer_count();
223 #ifdef SMP
224 	lwkt_cpusync_simple(-1, restoreclocks_remote, &base);
225 #else
226 	mycpu->gd_cpuclock_base = base;
227 #endif
228 }
229 
230 /*
231  * This sets the current real time of day.  Timespecs are in seconds and
232  * nanoseconds.  We do not mess with gd_time_seconds and gd_cpuclock_base,
233  * instead we adjust basetime so basetime + gd_* results in the current
234  * time of day.  This way the gd_* fields are guarenteed to represent
235  * a monotonically increasing 'uptime' value.
236  */
237 void
238 set_timeofday(struct timespec *ts)
239 {
240 	struct timespec ts2;
241 
242 	/*
243 	 * XXX SMP / non-atomic basetime updates
244 	 */
245 	crit_enter();
246 	nanouptime(&ts2);
247 	basetime.tv_sec = ts->tv_sec - ts2.tv_sec;
248 	basetime.tv_nsec = ts->tv_nsec - ts2.tv_nsec;
249 	if (basetime.tv_nsec < 0) {
250 	    basetime.tv_nsec += 1000000000;
251 	    --basetime.tv_sec;
252 	}
253 	boottime.tv_sec = basetime.tv_sec - mycpu->gd_time_seconds;
254 	timedelta = 0;
255 	crit_exit();
256 }
257 
258 /*
259  * Each cpu has its own hardclock, but we only increments ticks and softticks
260  * on cpu #0.
261  *
262  * NOTE! systimer! the MP lock might not be held here.  We can only safely
263  * manipulate objects owned by the current cpu.
264  */
265 static void
266 hardclock(systimer_t info, struct intrframe *frame)
267 {
268 	sysclock_t cputicks;
269 	struct proc *p;
270 	struct pstats *pstats;
271 	struct globaldata *gd = mycpu;
272 
273 	/*
274 	 * Realtime updates are per-cpu.  Note that timer corrections as
275 	 * returned by microtime() and friends make an additional adjustment
276 	 * using a system-wise 'basetime', but the running time is always
277 	 * taken from the per-cpu globaldata area.  Since the same clock
278 	 * is distributing (XXX SMP) to all cpus, the per-cpu timebases
279 	 * stay in synch.
280 	 *
281 	 * Note that we never allow info->time (aka gd->gd_hardclock.time)
282 	 * to reverse index gd_cpuclock_base.
283 	 */
284 	cputicks = info->time - gd->gd_cpuclock_base;
285 	if (cputicks > cputimer_freq) {
286 		++gd->gd_time_seconds;
287 		gd->gd_cpuclock_base += cputimer_freq;
288 	}
289 
290 	/*
291 	 * The system-wide ticks and softticks are only updated by cpu #0.
292 	 * Callwheel actions are also (at the moment) only handled by cpu #0.
293 	 * Finally, we also do NTP related timedelta/tickdelta adjustments
294 	 * by adjusting basetime.
295 	 */
296 	if (gd->gd_cpuid == 0) {
297 	    struct timespec nts;
298 	    int leap;
299 
300 	    ++ticks;
301 
302 #ifdef DEVICE_POLLING
303 	    hardclock_device_poll();	/* mpsafe, short and quick */
304 #endif /* DEVICE_POLLING */
305 
306 	    if (TAILQ_FIRST(&callwheel[ticks & callwheelmask]) != NULL) {
307 		setsoftclock();
308 	    } else if (softticks + 1 == ticks) {
309 		++softticks;
310 	    }
311 
312 #if 0
313 	    if (tco->tc_poll_pps)
314 		tco->tc_poll_pps(tco);
315 #endif
316 	    /*
317 	     * Apply adjtime corrections.  At the moment only do this if
318 	     * we can get the MP lock to interlock with adjtime's modification
319 	     * of these variables.  Note that basetime adjustments are not
320 	     * MP safe either XXX.
321 	     */
322 	    if (timedelta != 0 && try_mplock()) {
323 		basetime.tv_nsec += tickdelta * 1000;
324 		if (basetime.tv_nsec >= 1000000000) {
325 		    basetime.tv_nsec -= 1000000000;
326 		    ++basetime.tv_sec;
327 		} else if (basetime.tv_nsec < 0) {
328 		    basetime.tv_nsec += 1000000000;
329 		    --basetime.tv_sec;
330 		}
331 		timedelta -= tickdelta;
332 		rel_mplock();
333 	    }
334 
335 	    /*
336 	     * Apply per-tick compensation.  ticks_adj adjusts for both
337 	     * offset and frequency, and could be negative.
338 	     */
339 	    if (nsec_adj != 0 && try_mplock()) {
340 		nsec_acc += nsec_adj;
341 		if (nsec_acc >= 0x100000000LL) {
342 		    basetime.tv_nsec += nsec_acc >> 32;
343 		    nsec_acc = (nsec_acc & 0xFFFFFFFFLL);
344 		} else if (nsec_acc <= -0x100000000LL) {
345 		    basetime.tv_nsec -= -nsec_acc >> 32;
346 		    nsec_acc = -(-nsec_acc & 0xFFFFFFFFLL);
347 		}
348 		if (basetime.tv_nsec >= 1000000000) {
349 		    basetime.tv_nsec -= 1000000000;
350 		    ++basetime.tv_sec;
351 		} else if (basetime.tv_nsec < 0) {
352 		    basetime.tv_nsec += 1000000000;
353 		    --basetime.tv_sec;
354 		}
355 		rel_mplock();
356 	    }
357 
358 	    /*
359 	     * If the realtime-adjusted seconds hand rolls over then tell
360 	     * ntp_update_second() what we did in the last second so it can
361 	     * calculate what to do in the next second.  It may also add
362 	     * or subtract a leap second.
363 	     */
364 	    getnanotime(&nts);
365 	    if (time_second != nts.tv_sec) {
366 		leap = ntp_update_second(time_second, &nsec_adj);
367 		basetime.tv_sec += leap;
368 		time_second = nts.tv_sec + leap;
369 		nsec_adj /= hz;
370 	    }
371 	}
372 
373 	/*
374 	 * ITimer handling is per-tick, per-cpu.  I don't think psignal()
375 	 * is mpsafe on curproc, so XXX get the mplock.
376 	 */
377 	if ((p = curproc) != NULL && try_mplock()) {
378 		pstats = p->p_stats;
379 		if (frame && CLKF_USERMODE(frame) &&
380 		    timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value) &&
381 		    itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], tick) == 0)
382 			psignal(p, SIGVTALRM);
383 		if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value) &&
384 		    itimerdecr(&pstats->p_timer[ITIMER_PROF], tick) == 0)
385 			psignal(p, SIGPROF);
386 		rel_mplock();
387 	}
388 	setdelayed();
389 }
390 
391 /*
392  * The statistics clock typically runs at a 125Hz rate, and is intended
393  * to be frequency offset from the hardclock (typ 100Hz).  It is per-cpu.
394  *
395  * NOTE! systimer! the MP lock might not be held here.  We can only safely
396  * manipulate objects owned by the current cpu.
397  *
398  * The stats clock is responsible for grabbing a profiling sample.
399  * Most of the statistics are only used by user-level statistics programs.
400  * The main exceptions are p->p_uticks, p->p_sticks, p->p_iticks, and
401  * p->p_estcpu.
402  *
403  * Like the other clocks, the stat clock is called from what is effectively
404  * a fast interrupt, so the context should be the thread/process that got
405  * interrupted.
406  */
407 static void
408 statclock(systimer_t info, struct intrframe *frame)
409 {
410 #ifdef GPROF
411 	struct gmonparam *g;
412 	int i;
413 #endif
414 	thread_t td;
415 	struct proc *p;
416 	int bump;
417 	struct timeval tv;
418 	struct timeval *stv;
419 
420 	/*
421 	 * How big was our timeslice relative to the last time?
422 	 */
423 	microuptime(&tv);	/* mpsafe */
424 	stv = &mycpu->gd_stattv;
425 	if (stv->tv_sec == 0) {
426 	    bump = 1;
427 	} else {
428 	    bump = tv.tv_usec - stv->tv_usec +
429 		(tv.tv_sec - stv->tv_sec) * 1000000;
430 	    if (bump < 0)
431 		bump = 0;
432 	    if (bump > 1000000)
433 		bump = 1000000;
434 	}
435 	*stv = tv;
436 
437 	td = curthread;
438 	p = td->td_proc;
439 
440 	if (frame && CLKF_USERMODE(frame)) {
441 		/*
442 		 * Came from userland, handle user time and deal with
443 		 * possible process.
444 		 */
445 		if (p && (p->p_flag & P_PROFIL))
446 			addupc_intr(p, CLKF_PC(frame), 1);
447 		td->td_uticks += bump;
448 
449 		/*
450 		 * Charge the time as appropriate
451 		 */
452 		if (p && p->p_nice > NZERO)
453 			cp_time[CP_NICE] += bump;
454 		else
455 			cp_time[CP_USER] += bump;
456 	} else {
457 #ifdef GPROF
458 		/*
459 		 * Kernel statistics are just like addupc_intr, only easier.
460 		 */
461 		g = &_gmonparam;
462 		if (g->state == GMON_PROF_ON && frame) {
463 			i = CLKF_PC(frame) - g->lowpc;
464 			if (i < g->textsize) {
465 				i /= HISTFRACTION * sizeof(*g->kcount);
466 				g->kcount[i]++;
467 			}
468 		}
469 #endif
470 		/*
471 		 * Came from kernel mode, so we were:
472 		 * - handling an interrupt,
473 		 * - doing syscall or trap work on behalf of the current
474 		 *   user process, or
475 		 * - spinning in the idle loop.
476 		 * Whichever it is, charge the time as appropriate.
477 		 * Note that we charge interrupts to the current process,
478 		 * regardless of whether they are ``for'' that process,
479 		 * so that we know how much of its real time was spent
480 		 * in ``non-process'' (i.e., interrupt) work.
481 		 *
482 		 * XXX assume system if frame is NULL.  A NULL frame
483 		 * can occur if ipi processing is done from an splx().
484 		 */
485 		if (frame && CLKF_INTR(frame))
486 			td->td_iticks += bump;
487 		else
488 			td->td_sticks += bump;
489 
490 		if (frame && CLKF_INTR(frame)) {
491 			cp_time[CP_INTR] += bump;
492 		} else {
493 			if (td == &mycpu->gd_idlethread)
494 				cp_time[CP_IDLE] += bump;
495 			else
496 				cp_time[CP_SYS] += bump;
497 		}
498 	}
499 }
500 
501 /*
502  * The scheduler clock typically runs at a 20Hz rate.  NOTE! systimer,
503  * the MP lock might not be held.  We can safely manipulate parts of curproc
504  * but that's about it.
505  */
506 static void
507 schedclock(systimer_t info, struct intrframe *frame)
508 {
509 	struct proc *p;
510 	struct pstats *pstats;
511 	struct rusage *ru;
512 	struct vmspace *vm;
513 	long rss;
514 
515 	schedulerclock(NULL);	/* mpsafe */
516 	if ((p = curproc) != NULL) {
517 		/* Update resource usage integrals and maximums. */
518 		if ((pstats = p->p_stats) != NULL &&
519 		    (ru = &pstats->p_ru) != NULL &&
520 		    (vm = p->p_vmspace) != NULL) {
521 			ru->ru_ixrss += pgtok(vm->vm_tsize);
522 			ru->ru_idrss += pgtok(vm->vm_dsize);
523 			ru->ru_isrss += pgtok(vm->vm_ssize);
524 			rss = pgtok(vmspace_resident_count(vm));
525 			if (ru->ru_maxrss < rss)
526 				ru->ru_maxrss = rss;
527 		}
528 	}
529 }
530 
531 /*
532  * Compute number of ticks for the specified amount of time.  The
533  * return value is intended to be used in a clock interrupt timed
534  * operation and guarenteed to meet or exceed the requested time.
535  * If the representation overflows, return INT_MAX.  The minimum return
536  * value is 1 ticks and the function will average the calculation up.
537  * If any value greater then 0 microseconds is supplied, a value
538  * of at least 2 will be returned to ensure that a near-term clock
539  * interrupt does not cause the timeout to occur (degenerately) early.
540  *
541  * Note that limit checks must take into account microseconds, which is
542  * done simply by using the smaller signed long maximum instead of
543  * the unsigned long maximum.
544  *
545  * If ints have 32 bits, then the maximum value for any timeout in
546  * 10ms ticks is 248 days.
547  */
548 int
549 tvtohz_high(struct timeval *tv)
550 {
551 	int ticks;
552 	long sec, usec;
553 
554 	sec = tv->tv_sec;
555 	usec = tv->tv_usec;
556 	if (usec < 0) {
557 		sec--;
558 		usec += 1000000;
559 	}
560 	if (sec < 0) {
561 #ifdef DIAGNOSTIC
562 		if (usec > 0) {
563 			sec++;
564 			usec -= 1000000;
565 		}
566 		printf("tvotohz: negative time difference %ld sec %ld usec\n",
567 		       sec, usec);
568 #endif
569 		ticks = 1;
570 	} else if (sec <= INT_MAX / hz) {
571 		ticks = (int)(sec * hz +
572 			    ((u_long)usec + (tick - 1)) / tick) + 1;
573 	} else {
574 		ticks = INT_MAX;
575 	}
576 	return (ticks);
577 }
578 
579 /*
580  * Compute number of ticks for the specified amount of time, erroring on
581  * the side of it being too low to ensure that sleeping the returned number
582  * of ticks will not result in a late return.
583  *
584  * The supplied timeval may not be negative and should be normalized.  A
585  * return value of 0 is possible if the timeval converts to less then
586  * 1 tick.
587  *
588  * If ints have 32 bits, then the maximum value for any timeout in
589  * 10ms ticks is 248 days.
590  */
591 int
592 tvtohz_low(struct timeval *tv)
593 {
594 	int ticks;
595 	long sec;
596 
597 	sec = tv->tv_sec;
598 	if (sec <= INT_MAX / hz)
599 		ticks = (int)(sec * hz + (u_long)tv->tv_usec / tick);
600 	else
601 		ticks = INT_MAX;
602 	return (ticks);
603 }
604 
605 
606 /*
607  * Start profiling on a process.
608  *
609  * Kernel profiling passes proc0 which never exits and hence
610  * keeps the profile clock running constantly.
611  */
612 void
613 startprofclock(struct proc *p)
614 {
615 	if ((p->p_flag & P_PROFIL) == 0) {
616 		p->p_flag |= P_PROFIL;
617 #if 0	/* XXX */
618 		if (++profprocs == 1 && stathz != 0) {
619 			s = splstatclock();
620 			psdiv = psratio;
621 			setstatclockrate(profhz);
622 			splx(s);
623 		}
624 #endif
625 	}
626 }
627 
628 /*
629  * Stop profiling on a process.
630  */
631 void
632 stopprofclock(struct proc *p)
633 {
634 	if (p->p_flag & P_PROFIL) {
635 		p->p_flag &= ~P_PROFIL;
636 #if 0	/* XXX */
637 		if (--profprocs == 0 && stathz != 0) {
638 			s = splstatclock();
639 			psdiv = 1;
640 			setstatclockrate(stathz);
641 			splx(s);
642 		}
643 #endif
644 	}
645 }
646 
647 /*
648  * Return information about system clocks.
649  */
650 static int
651 sysctl_kern_clockrate(SYSCTL_HANDLER_ARGS)
652 {
653 	struct clockinfo clkinfo;
654 	/*
655 	 * Construct clockinfo structure.
656 	 */
657 	clkinfo.hz = hz;
658 	clkinfo.tick = tick;
659 	clkinfo.tickadj = tickadj;
660 	clkinfo.profhz = profhz;
661 	clkinfo.stathz = stathz ? stathz : hz;
662 	return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req));
663 }
664 
665 SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, CTLTYPE_STRUCT|CTLFLAG_RD,
666 	0, 0, sysctl_kern_clockrate, "S,clockinfo","");
667 
668 /*
669  * We have eight functions for looking at the clock, four for
670  * microseconds and four for nanoseconds.  For each there is fast
671  * but less precise version "get{nano|micro}[up]time" which will
672  * return a time which is up to 1/HZ previous to the call, whereas
673  * the raw version "{nano|micro}[up]time" will return a timestamp
674  * which is as precise as possible.  The "up" variants return the
675  * time relative to system boot, these are well suited for time
676  * interval measurements.
677  *
678  * Each cpu independantly maintains the current time of day, so all
679  * we need to do to protect ourselves from changes is to do a loop
680  * check on the seconds field changing out from under us.
681  */
682 void
683 getmicrouptime(struct timeval *tvp)
684 {
685 	struct globaldata *gd = mycpu;
686 	sysclock_t delta;
687 
688 	do {
689 		tvp->tv_sec = gd->gd_time_seconds;
690 		delta = gd->gd_hardclock.time - gd->gd_cpuclock_base;
691 	} while (tvp->tv_sec != gd->gd_time_seconds);
692 	tvp->tv_usec = (cputimer_freq64_usec * delta) >> 32;
693 	if (tvp->tv_usec >= 1000000) {
694 		tvp->tv_usec -= 1000000;
695 		++tvp->tv_sec;
696 	}
697 }
698 
699 void
700 getnanouptime(struct timespec *tsp)
701 {
702 	struct globaldata *gd = mycpu;
703 	sysclock_t delta;
704 
705 	do {
706 		tsp->tv_sec = gd->gd_time_seconds;
707 		delta = gd->gd_hardclock.time - gd->gd_cpuclock_base;
708 	} while (tsp->tv_sec != gd->gd_time_seconds);
709 	tsp->tv_nsec = (cputimer_freq64_nsec * delta) >> 32;
710 	if (tsp->tv_nsec >= 1000000000) {
711 		tsp->tv_nsec -= 1000000000;
712 		++tsp->tv_sec;
713 	}
714 }
715 
716 void
717 microuptime(struct timeval *tvp)
718 {
719 	struct globaldata *gd = mycpu;
720 	sysclock_t delta;
721 
722 	do {
723 		tvp->tv_sec = gd->gd_time_seconds;
724 		delta = cputimer_count() - gd->gd_cpuclock_base;
725 	} while (tvp->tv_sec != gd->gd_time_seconds);
726 	tvp->tv_usec = (cputimer_freq64_usec * delta) >> 32;
727 	if (tvp->tv_usec >= 1000000) {
728 		tvp->tv_usec -= 1000000;
729 		++tvp->tv_sec;
730 	}
731 }
732 
733 void
734 nanouptime(struct timespec *tsp)
735 {
736 	struct globaldata *gd = mycpu;
737 	sysclock_t delta;
738 
739 	do {
740 		tsp->tv_sec = gd->gd_time_seconds;
741 		delta = cputimer_count() - gd->gd_cpuclock_base;
742 	} while (tsp->tv_sec != gd->gd_time_seconds);
743 	tsp->tv_nsec = (cputimer_freq64_nsec * delta) >> 32;
744 	if (tsp->tv_nsec >= 1000000000) {
745 		tsp->tv_nsec -= 1000000000;
746 		++tsp->tv_sec;
747 	}
748 }
749 
750 /*
751  * realtime routines
752  */
753 
754 void
755 getmicrotime(struct timeval *tvp)
756 {
757 	struct globaldata *gd = mycpu;
758 	sysclock_t delta;
759 
760 	do {
761 		tvp->tv_sec = gd->gd_time_seconds;
762 		delta = gd->gd_hardclock.time - gd->gd_cpuclock_base;
763 	} while (tvp->tv_sec != gd->gd_time_seconds);
764 	tvp->tv_usec = (cputimer_freq64_usec * delta) >> 32;
765 
766 	tvp->tv_sec += basetime.tv_sec;
767 	tvp->tv_usec += basetime.tv_nsec / 1000;
768 	while (tvp->tv_usec >= 1000000) {
769 		tvp->tv_usec -= 1000000;
770 		++tvp->tv_sec;
771 	}
772 }
773 
774 void
775 getnanotime(struct timespec *tsp)
776 {
777 	struct globaldata *gd = mycpu;
778 	sysclock_t delta;
779 
780 	do {
781 		tsp->tv_sec = gd->gd_time_seconds;
782 		delta = gd->gd_hardclock.time - gd->gd_cpuclock_base;
783 	} while (tsp->tv_sec != gd->gd_time_seconds);
784 	tsp->tv_nsec = (cputimer_freq64_nsec * delta) >> 32;
785 
786 	tsp->tv_sec += basetime.tv_sec;
787 	tsp->tv_nsec += basetime.tv_nsec;
788 	while (tsp->tv_nsec >= 1000000000) {
789 		tsp->tv_nsec -= 1000000000;
790 		++tsp->tv_sec;
791 	}
792 }
793 
794 void
795 microtime(struct timeval *tvp)
796 {
797 	struct globaldata *gd = mycpu;
798 	sysclock_t delta;
799 
800 	do {
801 		tvp->tv_sec = gd->gd_time_seconds;
802 		delta = cputimer_count() - gd->gd_cpuclock_base;
803 	} while (tvp->tv_sec != gd->gd_time_seconds);
804 	tvp->tv_usec = (cputimer_freq64_usec * delta) >> 32;
805 
806 	tvp->tv_sec += basetime.tv_sec;
807 	tvp->tv_usec += basetime.tv_nsec / 1000;
808 	while (tvp->tv_usec >= 1000000) {
809 		tvp->tv_usec -= 1000000;
810 		++tvp->tv_sec;
811 	}
812 }
813 
814 void
815 nanotime(struct timespec *tsp)
816 {
817 	struct globaldata *gd = mycpu;
818 	sysclock_t delta;
819 
820 	do {
821 		tsp->tv_sec = gd->gd_time_seconds;
822 		delta = cputimer_count() - gd->gd_cpuclock_base;
823 	} while (tsp->tv_sec != gd->gd_time_seconds);
824 	tsp->tv_nsec = (cputimer_freq64_nsec * delta) >> 32;
825 
826 	tsp->tv_sec += basetime.tv_sec;
827 	tsp->tv_nsec += basetime.tv_nsec;
828 	while (tsp->tv_nsec >= 1000000000) {
829 		tsp->tv_nsec -= 1000000000;
830 		++tsp->tv_sec;
831 	}
832 }
833 
834 int
835 pps_ioctl(u_long cmd, caddr_t data, struct pps_state *pps)
836 {
837 	pps_params_t *app;
838 	struct pps_fetch_args *fapi;
839 #ifdef PPS_SYNC
840 	struct pps_kcbind_args *kapi;
841 #endif
842 
843 	switch (cmd) {
844 	case PPS_IOC_CREATE:
845 		return (0);
846 	case PPS_IOC_DESTROY:
847 		return (0);
848 	case PPS_IOC_SETPARAMS:
849 		app = (pps_params_t *)data;
850 		if (app->mode & ~pps->ppscap)
851 			return (EINVAL);
852 		pps->ppsparam = *app;
853 		return (0);
854 	case PPS_IOC_GETPARAMS:
855 		app = (pps_params_t *)data;
856 		*app = pps->ppsparam;
857 		app->api_version = PPS_API_VERS_1;
858 		return (0);
859 	case PPS_IOC_GETCAP:
860 		*(int*)data = pps->ppscap;
861 		return (0);
862 	case PPS_IOC_FETCH:
863 		fapi = (struct pps_fetch_args *)data;
864 		if (fapi->tsformat && fapi->tsformat != PPS_TSFMT_TSPEC)
865 			return (EINVAL);
866 		if (fapi->timeout.tv_sec || fapi->timeout.tv_nsec)
867 			return (EOPNOTSUPP);
868 		pps->ppsinfo.current_mode = pps->ppsparam.mode;
869 		fapi->pps_info_buf = pps->ppsinfo;
870 		return (0);
871 	case PPS_IOC_KCBIND:
872 #ifdef PPS_SYNC
873 		kapi = (struct pps_kcbind_args *)data;
874 		/* XXX Only root should be able to do this */
875 		if (kapi->tsformat && kapi->tsformat != PPS_TSFMT_TSPEC)
876 			return (EINVAL);
877 		if (kapi->kernel_consumer != PPS_KC_HARDPPS)
878 			return (EINVAL);
879 		if (kapi->edge & ~pps->ppscap)
880 			return (EINVAL);
881 		pps->kcmode = kapi->edge;
882 		return (0);
883 #else
884 		return (EOPNOTSUPP);
885 #endif
886 	default:
887 		return (ENOTTY);
888 	}
889 }
890 
891 void
892 pps_init(struct pps_state *pps)
893 {
894 	pps->ppscap |= PPS_TSFMT_TSPEC;
895 	if (pps->ppscap & PPS_CAPTUREASSERT)
896 		pps->ppscap |= PPS_OFFSETASSERT;
897 	if (pps->ppscap & PPS_CAPTURECLEAR)
898 		pps->ppscap |= PPS_OFFSETCLEAR;
899 }
900 
901 void
902 pps_event(struct pps_state *pps, sysclock_t count, int event)
903 {
904 	struct globaldata *gd;
905 	struct timespec *tsp;
906 	struct timespec *osp;
907 	struct timespec ts;
908 	sysclock_t *pcount;
909 #ifdef PPS_SYNC
910 	sysclock_t tcount;
911 #endif
912 	sysclock_t delta;
913 	pps_seq_t *pseq;
914 	int foff;
915 	int fhard;
916 
917 	gd = mycpu;
918 
919 	/* Things would be easier with arrays... */
920 	if (event == PPS_CAPTUREASSERT) {
921 		tsp = &pps->ppsinfo.assert_timestamp;
922 		osp = &pps->ppsparam.assert_offset;
923 		foff = pps->ppsparam.mode & PPS_OFFSETASSERT;
924 		fhard = pps->kcmode & PPS_CAPTUREASSERT;
925 		pcount = &pps->ppscount[0];
926 		pseq = &pps->ppsinfo.assert_sequence;
927 	} else {
928 		tsp = &pps->ppsinfo.clear_timestamp;
929 		osp = &pps->ppsparam.clear_offset;
930 		foff = pps->ppsparam.mode & PPS_OFFSETCLEAR;
931 		fhard = pps->kcmode & PPS_CAPTURECLEAR;
932 		pcount = &pps->ppscount[1];
933 		pseq = &pps->ppsinfo.clear_sequence;
934 	}
935 
936 	/* Nothing really happened */
937 	if (*pcount == count)
938 		return;
939 
940 	*pcount = count;
941 
942 	do {
943 		ts.tv_sec = gd->gd_time_seconds;
944 		delta = count - gd->gd_cpuclock_base;
945 	} while (ts.tv_sec != gd->gd_time_seconds);
946 	if (delta > cputimer_freq) {
947 		ts.tv_sec += delta / cputimer_freq;
948 		delta %= cputimer_freq;
949 	}
950 	ts.tv_nsec = (cputimer_freq64_nsec * delta) >> 32;
951 	ts.tv_sec += basetime.tv_sec;
952 	ts.tv_nsec += basetime.tv_nsec;
953 	while (ts.tv_nsec >= 1000000000) {
954 		ts.tv_nsec -= 1000000000;
955 		++ts.tv_sec;
956 	}
957 
958 	(*pseq)++;
959 	*tsp = ts;
960 
961 	if (foff) {
962 		timespecadd(tsp, osp);
963 		if (tsp->tv_nsec < 0) {
964 			tsp->tv_nsec += 1000000000;
965 			tsp->tv_sec -= 1;
966 		}
967 	}
968 #ifdef PPS_SYNC
969 	if (fhard) {
970 		/* magic, at its best... */
971 		tcount = count - pps->ppscount[2];
972 		pps->ppscount[2] = count;
973 		delta = (cputimer_freq64_nsec * tcount) >> 32;
974 		hardpps(tsp, delta);
975 	}
976 #endif
977 }
978 
979