xref: /dragonfly/sys/kern/kern_clock.c (revision 2c603719)
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 1.26 2004/11/12 17:50:56 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, but that it is possible for
283 	 * it to temporarily get behind in the seconds if something in the
284 	 * system locks interrupts for a long period of time.  Since periodic
285 	 * timers count events, though everything should resynch again
286 	 * immediately.
287 	 */
288 	cputicks = info->time - gd->gd_cpuclock_base;
289 	if (cputicks >= cputimer_freq) {
290 		++gd->gd_time_seconds;
291 		gd->gd_cpuclock_base += cputimer_freq;
292 	}
293 
294 	/*
295 	 * The system-wide ticks counter and NTP related timedelta/tickdelta
296 	 * adjustments only occur on cpu #0.  NTP adjustments are accomplished
297 	 * by updating basetime.
298 	 */
299 	if (gd->gd_cpuid == 0) {
300 	    struct timespec nts;
301 	    int leap;
302 
303 	    ++ticks;
304 
305 #ifdef DEVICE_POLLING
306 	    hardclock_device_poll();	/* mpsafe, short and quick */
307 #endif /* DEVICE_POLLING */
308 
309 #if 0
310 	    if (tco->tc_poll_pps)
311 		tco->tc_poll_pps(tco);
312 #endif
313 	    /*
314 	     * Apply adjtime corrections.  At the moment only do this if
315 	     * we can get the MP lock to interlock with adjtime's modification
316 	     * of these variables.  Note that basetime adjustments are not
317 	     * MP safe either XXX.
318 	     */
319 	    if (timedelta != 0 && try_mplock()) {
320 		basetime.tv_nsec += tickdelta * 1000;
321 		if (basetime.tv_nsec >= 1000000000) {
322 		    basetime.tv_nsec -= 1000000000;
323 		    ++basetime.tv_sec;
324 		} else if (basetime.tv_nsec < 0) {
325 		    basetime.tv_nsec += 1000000000;
326 		    --basetime.tv_sec;
327 		}
328 		timedelta -= tickdelta;
329 		rel_mplock();
330 	    }
331 
332 	    /*
333 	     * Apply per-tick compensation.  ticks_adj adjusts for both
334 	     * offset and frequency, and could be negative.
335 	     */
336 	    if (nsec_adj != 0 && try_mplock()) {
337 		nsec_acc += nsec_adj;
338 		if (nsec_acc >= 0x100000000LL) {
339 		    basetime.tv_nsec += nsec_acc >> 32;
340 		    nsec_acc = (nsec_acc & 0xFFFFFFFFLL);
341 		} else if (nsec_acc <= -0x100000000LL) {
342 		    basetime.tv_nsec -= -nsec_acc >> 32;
343 		    nsec_acc = -(-nsec_acc & 0xFFFFFFFFLL);
344 		}
345 		if (basetime.tv_nsec >= 1000000000) {
346 		    basetime.tv_nsec -= 1000000000;
347 		    ++basetime.tv_sec;
348 		} else if (basetime.tv_nsec < 0) {
349 		    basetime.tv_nsec += 1000000000;
350 		    --basetime.tv_sec;
351 		}
352 		rel_mplock();
353 	    }
354 
355 	    /*
356 	     * If the realtime-adjusted seconds hand rolls over then tell
357 	     * ntp_update_second() what we did in the last second so it can
358 	     * calculate what to do in the next second.  It may also add
359 	     * or subtract a leap second.
360 	     */
361 	    getnanotime(&nts);
362 	    if (time_second != nts.tv_sec) {
363 		leap = ntp_update_second(time_second, &nsec_adj);
364 		basetime.tv_sec += leap;
365 		time_second = nts.tv_sec + leap;
366 		nsec_adj /= hz;
367 	    }
368 	}
369 
370 	/*
371 	 * softticks are handled for all cpus
372 	 */
373 	hardclock_softtick(gd);
374 
375 	/*
376 	 * ITimer handling is per-tick, per-cpu.  I don't think psignal()
377 	 * is mpsafe on curproc, so XXX get the mplock.
378 	 */
379 	if ((p = curproc) != NULL && try_mplock()) {
380 		pstats = p->p_stats;
381 		if (frame && CLKF_USERMODE(frame) &&
382 		    timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value) &&
383 		    itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], tick) == 0)
384 			psignal(p, SIGVTALRM);
385 		if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value) &&
386 		    itimerdecr(&pstats->p_timer[ITIMER_PROF], tick) == 0)
387 			psignal(p, SIGPROF);
388 		rel_mplock();
389 	}
390 	setdelayed();
391 }
392 
393 /*
394  * The statistics clock typically runs at a 125Hz rate, and is intended
395  * to be frequency offset from the hardclock (typ 100Hz).  It is per-cpu.
396  *
397  * NOTE! systimer! the MP lock might not be held here.  We can only safely
398  * manipulate objects owned by the current cpu.
399  *
400  * The stats clock is responsible for grabbing a profiling sample.
401  * Most of the statistics are only used by user-level statistics programs.
402  * The main exceptions are p->p_uticks, p->p_sticks, p->p_iticks, and
403  * p->p_estcpu.
404  *
405  * Like the other clocks, the stat clock is called from what is effectively
406  * a fast interrupt, so the context should be the thread/process that got
407  * interrupted.
408  */
409 static void
410 statclock(systimer_t info, struct intrframe *frame)
411 {
412 #ifdef GPROF
413 	struct gmonparam *g;
414 	int i;
415 #endif
416 	thread_t td;
417 	struct proc *p;
418 	int bump;
419 	struct timeval tv;
420 	struct timeval *stv;
421 
422 	/*
423 	 * How big was our timeslice relative to the last time?
424 	 */
425 	microuptime(&tv);	/* mpsafe */
426 	stv = &mycpu->gd_stattv;
427 	if (stv->tv_sec == 0) {
428 	    bump = 1;
429 	} else {
430 	    bump = tv.tv_usec - stv->tv_usec +
431 		(tv.tv_sec - stv->tv_sec) * 1000000;
432 	    if (bump < 0)
433 		bump = 0;
434 	    if (bump > 1000000)
435 		bump = 1000000;
436 	}
437 	*stv = tv;
438 
439 	td = curthread;
440 	p = td->td_proc;
441 
442 	if (frame && CLKF_USERMODE(frame)) {
443 		/*
444 		 * Came from userland, handle user time and deal with
445 		 * possible process.
446 		 */
447 		if (p && (p->p_flag & P_PROFIL))
448 			addupc_intr(p, CLKF_PC(frame), 1);
449 		td->td_uticks += bump;
450 
451 		/*
452 		 * Charge the time as appropriate
453 		 */
454 		if (p && p->p_nice > NZERO)
455 			cp_time[CP_NICE] += bump;
456 		else
457 			cp_time[CP_USER] += bump;
458 	} else {
459 #ifdef GPROF
460 		/*
461 		 * Kernel statistics are just like addupc_intr, only easier.
462 		 */
463 		g = &_gmonparam;
464 		if (g->state == GMON_PROF_ON && frame) {
465 			i = CLKF_PC(frame) - g->lowpc;
466 			if (i < g->textsize) {
467 				i /= HISTFRACTION * sizeof(*g->kcount);
468 				g->kcount[i]++;
469 			}
470 		}
471 #endif
472 		/*
473 		 * Came from kernel mode, so we were:
474 		 * - handling an interrupt,
475 		 * - doing syscall or trap work on behalf of the current
476 		 *   user process, or
477 		 * - spinning in the idle loop.
478 		 * Whichever it is, charge the time as appropriate.
479 		 * Note that we charge interrupts to the current process,
480 		 * regardless of whether they are ``for'' that process,
481 		 * so that we know how much of its real time was spent
482 		 * in ``non-process'' (i.e., interrupt) work.
483 		 *
484 		 * XXX assume system if frame is NULL.  A NULL frame
485 		 * can occur if ipi processing is done from an splx().
486 		 */
487 		if (frame && CLKF_INTR(frame))
488 			td->td_iticks += bump;
489 		else
490 			td->td_sticks += bump;
491 
492 		if (frame && CLKF_INTR(frame)) {
493 			cp_time[CP_INTR] += bump;
494 		} else {
495 			if (td == &mycpu->gd_idlethread)
496 				cp_time[CP_IDLE] += bump;
497 			else
498 				cp_time[CP_SYS] += bump;
499 		}
500 	}
501 }
502 
503 /*
504  * The scheduler clock typically runs at a 20Hz rate.  NOTE! systimer,
505  * the MP lock might not be held.  We can safely manipulate parts of curproc
506  * but that's about it.
507  */
508 static void
509 schedclock(systimer_t info, struct intrframe *frame)
510 {
511 	struct proc *p;
512 	struct pstats *pstats;
513 	struct rusage *ru;
514 	struct vmspace *vm;
515 	long rss;
516 
517 	schedulerclock(NULL);	/* mpsafe */
518 	if ((p = curproc) != NULL) {
519 		/* Update resource usage integrals and maximums. */
520 		if ((pstats = p->p_stats) != NULL &&
521 		    (ru = &pstats->p_ru) != NULL &&
522 		    (vm = p->p_vmspace) != NULL) {
523 			ru->ru_ixrss += pgtok(vm->vm_tsize);
524 			ru->ru_idrss += pgtok(vm->vm_dsize);
525 			ru->ru_isrss += pgtok(vm->vm_ssize);
526 			rss = pgtok(vmspace_resident_count(vm));
527 			if (ru->ru_maxrss < rss)
528 				ru->ru_maxrss = rss;
529 		}
530 	}
531 }
532 
533 /*
534  * Compute number of ticks for the specified amount of time.  The
535  * return value is intended to be used in a clock interrupt timed
536  * operation and guarenteed to meet or exceed the requested time.
537  * If the representation overflows, return INT_MAX.  The minimum return
538  * value is 1 ticks and the function will average the calculation up.
539  * If any value greater then 0 microseconds is supplied, a value
540  * of at least 2 will be returned to ensure that a near-term clock
541  * interrupt does not cause the timeout to occur (degenerately) early.
542  *
543  * Note that limit checks must take into account microseconds, which is
544  * done simply by using the smaller signed long maximum instead of
545  * the unsigned long maximum.
546  *
547  * If ints have 32 bits, then the maximum value for any timeout in
548  * 10ms ticks is 248 days.
549  */
550 int
551 tvtohz_high(struct timeval *tv)
552 {
553 	int ticks;
554 	long sec, usec;
555 
556 	sec = tv->tv_sec;
557 	usec = tv->tv_usec;
558 	if (usec < 0) {
559 		sec--;
560 		usec += 1000000;
561 	}
562 	if (sec < 0) {
563 #ifdef DIAGNOSTIC
564 		if (usec > 0) {
565 			sec++;
566 			usec -= 1000000;
567 		}
568 		printf("tvotohz: negative time difference %ld sec %ld usec\n",
569 		       sec, usec);
570 #endif
571 		ticks = 1;
572 	} else if (sec <= INT_MAX / hz) {
573 		ticks = (int)(sec * hz +
574 			    ((u_long)usec + (tick - 1)) / tick) + 1;
575 	} else {
576 		ticks = INT_MAX;
577 	}
578 	return (ticks);
579 }
580 
581 /*
582  * Compute number of ticks for the specified amount of time, erroring on
583  * the side of it being too low to ensure that sleeping the returned number
584  * of ticks will not result in a late return.
585  *
586  * The supplied timeval may not be negative and should be normalized.  A
587  * return value of 0 is possible if the timeval converts to less then
588  * 1 tick.
589  *
590  * If ints have 32 bits, then the maximum value for any timeout in
591  * 10ms ticks is 248 days.
592  */
593 int
594 tvtohz_low(struct timeval *tv)
595 {
596 	int ticks;
597 	long sec;
598 
599 	sec = tv->tv_sec;
600 	if (sec <= INT_MAX / hz)
601 		ticks = (int)(sec * hz + (u_long)tv->tv_usec / tick);
602 	else
603 		ticks = INT_MAX;
604 	return (ticks);
605 }
606 
607 
608 /*
609  * Start profiling on a process.
610  *
611  * Kernel profiling passes proc0 which never exits and hence
612  * keeps the profile clock running constantly.
613  */
614 void
615 startprofclock(struct proc *p)
616 {
617 	if ((p->p_flag & P_PROFIL) == 0) {
618 		p->p_flag |= P_PROFIL;
619 #if 0	/* XXX */
620 		if (++profprocs == 1 && stathz != 0) {
621 			s = splstatclock();
622 			psdiv = psratio;
623 			setstatclockrate(profhz);
624 			splx(s);
625 		}
626 #endif
627 	}
628 }
629 
630 /*
631  * Stop profiling on a process.
632  */
633 void
634 stopprofclock(struct proc *p)
635 {
636 	if (p->p_flag & P_PROFIL) {
637 		p->p_flag &= ~P_PROFIL;
638 #if 0	/* XXX */
639 		if (--profprocs == 0 && stathz != 0) {
640 			s = splstatclock();
641 			psdiv = 1;
642 			setstatclockrate(stathz);
643 			splx(s);
644 		}
645 #endif
646 	}
647 }
648 
649 /*
650  * Return information about system clocks.
651  */
652 static int
653 sysctl_kern_clockrate(SYSCTL_HANDLER_ARGS)
654 {
655 	struct clockinfo clkinfo;
656 	/*
657 	 * Construct clockinfo structure.
658 	 */
659 	clkinfo.hz = hz;
660 	clkinfo.tick = tick;
661 	clkinfo.tickadj = tickadj;
662 	clkinfo.profhz = profhz;
663 	clkinfo.stathz = stathz ? stathz : hz;
664 	return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req));
665 }
666 
667 SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, CTLTYPE_STRUCT|CTLFLAG_RD,
668 	0, 0, sysctl_kern_clockrate, "S,clockinfo","");
669 
670 /*
671  * We have eight functions for looking at the clock, four for
672  * microseconds and four for nanoseconds.  For each there is fast
673  * but less precise version "get{nano|micro}[up]time" which will
674  * return a time which is up to 1/HZ previous to the call, whereas
675  * the raw version "{nano|micro}[up]time" will return a timestamp
676  * which is as precise as possible.  The "up" variants return the
677  * time relative to system boot, these are well suited for time
678  * interval measurements.
679  *
680  * Each cpu independantly maintains the current time of day, so all
681  * we need to do to protect ourselves from changes is to do a loop
682  * check on the seconds field changing out from under us.
683  *
684  * The system timer maintains a 32 bit count and due to various issues
685  * it is possible for the calculated delta to occassionally exceed
686  * cputimer_freq.  If this occurs the cputimer_freq64_nsec multiplication
687  * can easily overflow, so we deal with the case.  For uniformity we deal
688  * with the case in the usec case too.
689  */
690 void
691 getmicrouptime(struct timeval *tvp)
692 {
693 	struct globaldata *gd = mycpu;
694 	sysclock_t delta;
695 
696 	do {
697 		tvp->tv_sec = gd->gd_time_seconds;
698 		delta = gd->gd_hardclock.time - gd->gd_cpuclock_base;
699 	} while (tvp->tv_sec != gd->gd_time_seconds);
700 
701 	if (delta >= cputimer_freq) {
702 		tvp->tv_sec += delta / cputimer_freq;
703 		delta %= cputimer_freq;
704 	}
705 	tvp->tv_usec = (cputimer_freq64_usec * delta) >> 32;
706 	if (tvp->tv_usec >= 1000000) {
707 		tvp->tv_usec -= 1000000;
708 		++tvp->tv_sec;
709 	}
710 }
711 
712 void
713 getnanouptime(struct timespec *tsp)
714 {
715 	struct globaldata *gd = mycpu;
716 	sysclock_t delta;
717 
718 	do {
719 		tsp->tv_sec = gd->gd_time_seconds;
720 		delta = gd->gd_hardclock.time - gd->gd_cpuclock_base;
721 	} while (tsp->tv_sec != gd->gd_time_seconds);
722 
723 	if (delta >= cputimer_freq) {
724 		tsp->tv_sec += delta / cputimer_freq;
725 		delta %= cputimer_freq;
726 	}
727 	tsp->tv_nsec = (cputimer_freq64_nsec * delta) >> 32;
728 }
729 
730 void
731 microuptime(struct timeval *tvp)
732 {
733 	struct globaldata *gd = mycpu;
734 	sysclock_t delta;
735 
736 	do {
737 		tvp->tv_sec = gd->gd_time_seconds;
738 		delta = cputimer_count() - gd->gd_cpuclock_base;
739 	} while (tvp->tv_sec != gd->gd_time_seconds);
740 
741 	if (delta >= cputimer_freq) {
742 		tvp->tv_sec += delta / cputimer_freq;
743 		delta %= cputimer_freq;
744 	}
745 	tvp->tv_usec = (cputimer_freq64_usec * delta) >> 32;
746 }
747 
748 void
749 nanouptime(struct timespec *tsp)
750 {
751 	struct globaldata *gd = mycpu;
752 	sysclock_t delta;
753 
754 	do {
755 		tsp->tv_sec = gd->gd_time_seconds;
756 		delta = cputimer_count() - gd->gd_cpuclock_base;
757 	} while (tsp->tv_sec != gd->gd_time_seconds);
758 
759 	if (delta >= cputimer_freq) {
760 		tsp->tv_sec += delta / cputimer_freq;
761 		delta %= cputimer_freq;
762 	}
763 	tsp->tv_nsec = (cputimer_freq64_nsec * delta) >> 32;
764 }
765 
766 /*
767  * realtime routines
768  */
769 
770 void
771 getmicrotime(struct timeval *tvp)
772 {
773 	struct globaldata *gd = mycpu;
774 	sysclock_t delta;
775 
776 	do {
777 		tvp->tv_sec = gd->gd_time_seconds;
778 		delta = gd->gd_hardclock.time - gd->gd_cpuclock_base;
779 	} while (tvp->tv_sec != gd->gd_time_seconds);
780 
781 	if (delta >= cputimer_freq) {
782 		tvp->tv_sec += delta / cputimer_freq;
783 		delta %= cputimer_freq;
784 	}
785 	tvp->tv_usec = (cputimer_freq64_usec * delta) >> 32;
786 
787 	tvp->tv_sec += basetime.tv_sec;
788 	tvp->tv_usec += basetime.tv_nsec / 1000;
789 	while (tvp->tv_usec >= 1000000) {
790 		tvp->tv_usec -= 1000000;
791 		++tvp->tv_sec;
792 	}
793 }
794 
795 void
796 getnanotime(struct timespec *tsp)
797 {
798 	struct globaldata *gd = mycpu;
799 	sysclock_t delta;
800 
801 	do {
802 		tsp->tv_sec = gd->gd_time_seconds;
803 		delta = gd->gd_hardclock.time - gd->gd_cpuclock_base;
804 	} while (tsp->tv_sec != gd->gd_time_seconds);
805 
806 	if (delta >= cputimer_freq) {
807 		tsp->tv_sec += delta / cputimer_freq;
808 		delta %= cputimer_freq;
809 	}
810 	tsp->tv_nsec = (cputimer_freq64_nsec * delta) >> 32;
811 
812 	tsp->tv_sec += basetime.tv_sec;
813 	tsp->tv_nsec += basetime.tv_nsec;
814 	while (tsp->tv_nsec >= 1000000000) {
815 		tsp->tv_nsec -= 1000000000;
816 		++tsp->tv_sec;
817 	}
818 }
819 
820 void
821 microtime(struct timeval *tvp)
822 {
823 	struct globaldata *gd = mycpu;
824 	sysclock_t delta;
825 
826 	do {
827 		tvp->tv_sec = gd->gd_time_seconds;
828 		delta = cputimer_count() - gd->gd_cpuclock_base;
829 	} while (tvp->tv_sec != gd->gd_time_seconds);
830 
831 	if (delta >= cputimer_freq) {
832 		tvp->tv_sec += delta / cputimer_freq;
833 		delta %= cputimer_freq;
834 	}
835 	tvp->tv_usec = (cputimer_freq64_usec * delta) >> 32;
836 
837 	tvp->tv_sec += basetime.tv_sec;
838 	tvp->tv_usec += basetime.tv_nsec / 1000;
839 	while (tvp->tv_usec >= 1000000) {
840 		tvp->tv_usec -= 1000000;
841 		++tvp->tv_sec;
842 	}
843 }
844 
845 void
846 nanotime(struct timespec *tsp)
847 {
848 	struct globaldata *gd = mycpu;
849 	sysclock_t delta;
850 
851 	do {
852 		tsp->tv_sec = gd->gd_time_seconds;
853 		delta = cputimer_count() - gd->gd_cpuclock_base;
854 	} while (tsp->tv_sec != gd->gd_time_seconds);
855 
856 	if (delta >= cputimer_freq) {
857 		tsp->tv_sec += delta / cputimer_freq;
858 		delta %= cputimer_freq;
859 	}
860 	tsp->tv_nsec = (cputimer_freq64_nsec * delta) >> 32;
861 
862 	tsp->tv_sec += basetime.tv_sec;
863 	tsp->tv_nsec += basetime.tv_nsec;
864 	while (tsp->tv_nsec >= 1000000000) {
865 		tsp->tv_nsec -= 1000000000;
866 		++tsp->tv_sec;
867 	}
868 }
869 
870 int
871 pps_ioctl(u_long cmd, caddr_t data, struct pps_state *pps)
872 {
873 	pps_params_t *app;
874 	struct pps_fetch_args *fapi;
875 #ifdef PPS_SYNC
876 	struct pps_kcbind_args *kapi;
877 #endif
878 
879 	switch (cmd) {
880 	case PPS_IOC_CREATE:
881 		return (0);
882 	case PPS_IOC_DESTROY:
883 		return (0);
884 	case PPS_IOC_SETPARAMS:
885 		app = (pps_params_t *)data;
886 		if (app->mode & ~pps->ppscap)
887 			return (EINVAL);
888 		pps->ppsparam = *app;
889 		return (0);
890 	case PPS_IOC_GETPARAMS:
891 		app = (pps_params_t *)data;
892 		*app = pps->ppsparam;
893 		app->api_version = PPS_API_VERS_1;
894 		return (0);
895 	case PPS_IOC_GETCAP:
896 		*(int*)data = pps->ppscap;
897 		return (0);
898 	case PPS_IOC_FETCH:
899 		fapi = (struct pps_fetch_args *)data;
900 		if (fapi->tsformat && fapi->tsformat != PPS_TSFMT_TSPEC)
901 			return (EINVAL);
902 		if (fapi->timeout.tv_sec || fapi->timeout.tv_nsec)
903 			return (EOPNOTSUPP);
904 		pps->ppsinfo.current_mode = pps->ppsparam.mode;
905 		fapi->pps_info_buf = pps->ppsinfo;
906 		return (0);
907 	case PPS_IOC_KCBIND:
908 #ifdef PPS_SYNC
909 		kapi = (struct pps_kcbind_args *)data;
910 		/* XXX Only root should be able to do this */
911 		if (kapi->tsformat && kapi->tsformat != PPS_TSFMT_TSPEC)
912 			return (EINVAL);
913 		if (kapi->kernel_consumer != PPS_KC_HARDPPS)
914 			return (EINVAL);
915 		if (kapi->edge & ~pps->ppscap)
916 			return (EINVAL);
917 		pps->kcmode = kapi->edge;
918 		return (0);
919 #else
920 		return (EOPNOTSUPP);
921 #endif
922 	default:
923 		return (ENOTTY);
924 	}
925 }
926 
927 void
928 pps_init(struct pps_state *pps)
929 {
930 	pps->ppscap |= PPS_TSFMT_TSPEC;
931 	if (pps->ppscap & PPS_CAPTUREASSERT)
932 		pps->ppscap |= PPS_OFFSETASSERT;
933 	if (pps->ppscap & PPS_CAPTURECLEAR)
934 		pps->ppscap |= PPS_OFFSETCLEAR;
935 }
936 
937 void
938 pps_event(struct pps_state *pps, sysclock_t count, int event)
939 {
940 	struct globaldata *gd;
941 	struct timespec *tsp;
942 	struct timespec *osp;
943 	struct timespec ts;
944 	sysclock_t *pcount;
945 #ifdef PPS_SYNC
946 	sysclock_t tcount;
947 #endif
948 	sysclock_t delta;
949 	pps_seq_t *pseq;
950 	int foff;
951 	int fhard;
952 
953 	gd = mycpu;
954 
955 	/* Things would be easier with arrays... */
956 	if (event == PPS_CAPTUREASSERT) {
957 		tsp = &pps->ppsinfo.assert_timestamp;
958 		osp = &pps->ppsparam.assert_offset;
959 		foff = pps->ppsparam.mode & PPS_OFFSETASSERT;
960 		fhard = pps->kcmode & PPS_CAPTUREASSERT;
961 		pcount = &pps->ppscount[0];
962 		pseq = &pps->ppsinfo.assert_sequence;
963 	} else {
964 		tsp = &pps->ppsinfo.clear_timestamp;
965 		osp = &pps->ppsparam.clear_offset;
966 		foff = pps->ppsparam.mode & PPS_OFFSETCLEAR;
967 		fhard = pps->kcmode & PPS_CAPTURECLEAR;
968 		pcount = &pps->ppscount[1];
969 		pseq = &pps->ppsinfo.clear_sequence;
970 	}
971 
972 	/* Nothing really happened */
973 	if (*pcount == count)
974 		return;
975 
976 	*pcount = count;
977 
978 	do {
979 		ts.tv_sec = gd->gd_time_seconds;
980 		delta = count - gd->gd_cpuclock_base;
981 	} while (ts.tv_sec != gd->gd_time_seconds);
982 
983 	if (delta >= cputimer_freq) {
984 		ts.tv_sec += delta / cputimer_freq;
985 		delta %= cputimer_freq;
986 	}
987 	ts.tv_nsec = (cputimer_freq64_nsec * delta) >> 32;
988 	ts.tv_sec += basetime.tv_sec;
989 	ts.tv_nsec += basetime.tv_nsec;
990 	while (ts.tv_nsec >= 1000000000) {
991 		ts.tv_nsec -= 1000000000;
992 		++ts.tv_sec;
993 	}
994 
995 	(*pseq)++;
996 	*tsp = ts;
997 
998 	if (foff) {
999 		timespecadd(tsp, osp);
1000 		if (tsp->tv_nsec < 0) {
1001 			tsp->tv_nsec += 1000000000;
1002 			tsp->tv_sec -= 1;
1003 		}
1004 	}
1005 #ifdef PPS_SYNC
1006 	if (fhard) {
1007 		/* magic, at its best... */
1008 		tcount = count - pps->ppscount[2];
1009 		pps->ppscount[2] = count;
1010 		if (tcount >= cputimer_freq) {
1011 			delta = 1000000000 * (tcount / cputimer_freq) +
1012 				(cputimer_freq64_nsec *
1013 				 (tcount % cputimer_freq)) >> 32;
1014 		} else {
1015 			delta = (cputimer_freq64_nsec * tcount) >> 32;
1016 		}
1017 		hardpps(tsp, delta);
1018 	}
1019 #endif
1020 }
1021 
1022