2 * Copyright (c) 1982, 1986, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
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12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
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17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * @(#)kern_time.c 8.1 (Berkeley) 6/10/93
30 * $FreeBSD: src/sys/kern/kern_time.c,v 1.68.2.1 2002/10/01 08:00:41 bde Exp $
33 #include <sys/param.h>
34 #include <sys/systm.h>
36 #include <sys/sysproto.h>
37 #include <sys/resourcevar.h>
38 #include <sys/signalvar.h>
39 #include <sys/kernel.h>
40 #include <sys/sysent.h>
41 #include <sys/sysunion.h>
45 #include <sys/vnode.h>
46 #include <sys/sysctl.h>
47 #include <sys/kern_syscall.h>
49 #include <vm/vm_extern.h>
51 #include <sys/msgport2.h>
52 #include <sys/spinlock2.h>
53 #include <sys/thread2.h>
55 extern struct spinlock ntp_spin;
57 #define CPUCLOCK_BIT 0x80000000
58 #define CPUCLOCK_ID_MASK ~CPUCLOCK_BIT
59 #define CPUCLOCK2LWPID(clock_id) (((clockid_t)(clock_id) >> 32) & CPUCLOCK_ID_MASK)
60 #define CPUCLOCK2PID(clock_id) ((clock_id) & CPUCLOCK_ID_MASK)
61 #define MAKE_CPUCLOCK(pid, lwp_id) ((clockid_t)(lwp_id) << 32 | (pid) | CPUCLOCK_BIT)
66 * Time of day and interval timer support.
68 * These routines provide the kernel entry points to get and set
69 * the time-of-day and per-process interval timers. Subroutines
70 * here provide support for adding and subtracting timeval structures
71 * and decrementing interval timers, optionally reloading the interval
72 * timers when they expire.
75 static int settime(struct timeval *);
76 static void timevalfix(struct timeval *);
77 static void realitexpire(void *arg);
80 * Nanosleep tries very hard to sleep for a precisely requested time
81 * interval, down to 1uS. The administrator can impose a minimum delay
82 * and a delay below which we hard-loop instead of initiate a timer
83 * interrupt and sleep.
85 * For machines under high loads it might be beneficial to increase min_us
86 * to e.g. 1000uS (1ms) so spining processes sleep meaningfully.
88 static int nanosleep_min_us = 10;
89 static int nanosleep_hard_us = 100;
90 static int gettimeofday_quick = 0;
91 SYSCTL_INT(_kern, OID_AUTO, nanosleep_min_us, CTLFLAG_RW,
92 &nanosleep_min_us, 0, "");
93 SYSCTL_INT(_kern, OID_AUTO, nanosleep_hard_us, CTLFLAG_RW,
94 &nanosleep_hard_us, 0, "");
95 SYSCTL_INT(_kern, OID_AUTO, gettimeofday_quick, CTLFLAG_RW,
96 &gettimeofday_quick, 0, "");
98 static struct lock masterclock_lock = LOCK_INITIALIZER("mstrclk", 0, 0);
101 settime(struct timeval *tv)
103 struct timeval delta, tv1, tv2;
104 static struct timeval maxtime, laststep;
108 if ((origcpu = mycpu->gd_cpuid) != 0)
109 lwkt_setcpu_self(globaldata_find(0));
114 timevalsub(&delta, &tv1);
117 * If the system is secure, we do not allow the time to be
118 * set to a value earlier than 1 second less than the highest
119 * time we have yet seen. The worst a miscreant can do in
120 * this circumstance is "freeze" time. He couldn't go
123 * We similarly do not allow the clock to be stepped more
124 * than one second, nor more than once per second. This allows
125 * a miscreant to make the clock march double-time, but no worse.
127 if (securelevel > 1) {
128 if (delta.tv_sec < 0 || delta.tv_usec < 0) {
130 * Update maxtime to latest time we've seen.
132 if (tv1.tv_sec > maxtime.tv_sec)
135 timevalsub(&tv2, &maxtime);
136 if (tv2.tv_sec < -1) {
137 tv->tv_sec = maxtime.tv_sec - 1;
138 kprintf("Time adjustment clamped to -1 second\n");
141 if (tv1.tv_sec == laststep.tv_sec) {
145 if (delta.tv_sec > 1) {
146 tv->tv_sec = tv1.tv_sec + 1;
147 kprintf("Time adjustment clamped to +1 second\n");
153 ts.tv_sec = tv->tv_sec;
154 ts.tv_nsec = tv->tv_usec * 1000;
159 lwkt_setcpu_self(globaldata_find(origcpu));
166 get_process_cputime(struct proc *p, struct timespec *ats)
170 lwkt_gettoken(&p->p_token);
172 lwkt_reltoken(&p->p_token);
173 timevaladd(&ru.ru_utime, &ru.ru_stime);
174 TIMEVAL_TO_TIMESPEC(&ru.ru_utime, ats);
178 get_process_usertime(struct proc *p, struct timespec *ats)
182 lwkt_gettoken(&p->p_token);
184 lwkt_reltoken(&p->p_token);
185 TIMEVAL_TO_TIMESPEC(&ru.ru_utime, ats);
189 get_thread_cputime(struct thread *td, struct timespec *ats)
191 struct timeval sys, user;
193 calcru(td->td_lwp, &user, &sys);
194 timevaladd(&user, &sys);
195 TIMEVAL_TO_TIMESPEC(&user, ats);
202 kern_clock_gettime(clockid_t clock_id, struct timespec *ats)
211 case CLOCK_REALTIME_PRECISE:
214 case CLOCK_REALTIME_FAST:
217 case CLOCK_MONOTONIC:
218 case CLOCK_MONOTONIC_PRECISE:
220 case CLOCK_UPTIME_PRECISE:
223 case CLOCK_MONOTONIC_FAST:
224 case CLOCK_UPTIME_FAST:
228 get_process_usertime(p, ats);
231 case CLOCK_PROCESS_CPUTIME_ID:
232 get_process_cputime(p, ats);
235 ats->tv_sec = time_second;
238 case CLOCK_THREAD_CPUTIME_ID:
239 get_thread_cputime(curthread, ats);
242 if ((clock_id & CPUCLOCK_BIT) == 0)
244 if ((p = pfind(CPUCLOCK2PID(clock_id))) == NULL)
246 lwp_id = CPUCLOCK2LWPID(clock_id);
248 get_process_cputime(p, ats);
250 lwkt_gettoken(&p->p_token);
251 lp = lwp_rb_tree_RB_LOOKUP(&p->p_lwp_tree, lwp_id);
253 lwkt_reltoken(&p->p_token);
257 get_thread_cputime(lp->lwp_thread, ats);
258 lwkt_reltoken(&p->p_token);
269 sys_clock_gettime(struct clock_gettime_args *uap)
274 error = kern_clock_gettime(uap->clock_id, &ats);
276 error = copyout(&ats, uap->tp, sizeof(ats));
282 kern_clock_settime(clockid_t clock_id, struct timespec *ats)
284 struct thread *td = curthread;
288 if ((error = priv_check(td, PRIV_CLOCK_SETTIME)) != 0)
290 if (clock_id != CLOCK_REALTIME)
292 if (ats->tv_nsec < 0 || ats->tv_nsec >= 1000000000)
295 lockmgr(&masterclock_lock, LK_EXCLUSIVE);
296 TIMESPEC_TO_TIMEVAL(&atv, ats);
297 error = settime(&atv);
298 lockmgr(&masterclock_lock, LK_RELEASE);
307 sys_clock_settime(struct clock_settime_args *uap)
312 if ((error = copyin(uap->tp, &ats, sizeof(ats))) != 0)
315 error = kern_clock_settime(uap->clock_id, &ats);
324 kern_clock_getres(clockid_t clock_id, struct timespec *ts)
329 case CLOCK_REALTIME_FAST:
330 case CLOCK_REALTIME_PRECISE:
331 case CLOCK_MONOTONIC:
332 case CLOCK_MONOTONIC_FAST:
333 case CLOCK_MONOTONIC_PRECISE:
335 case CLOCK_UPTIME_FAST:
336 case CLOCK_UPTIME_PRECISE:
338 * Round up the result of the division cheaply
339 * by adding 1. Rounding up is especially important
340 * if rounding down would give 0. Perfect rounding
343 ts->tv_nsec = 1000000000 / sys_cputimer->freq + 1;
347 /* Accurately round up here because we can do so cheaply. */
348 ts->tv_nsec = (1000000000 + hz - 1) / hz;
354 case CLOCK_THREAD_CPUTIME_ID:
355 case CLOCK_PROCESS_CPUTIME_ID:
359 if ((clock_id & CPUCLOCK_BIT) != 0)
372 sys_clock_getres(struct clock_getres_args *uap)
377 error = kern_clock_getres(uap->clock_id, &ts);
379 error = copyout(&ts, uap->tp, sizeof(ts));
385 kern_getcpuclockid(pid_t pid, lwpid_t lwp_id, clockid_t *clock_id)
399 /* lwp_id can be 0 when called by clock_getcpuclockid() */
404 lwkt_gettoken(&p->p_token);
406 lwp_rb_tree_RB_LOOKUP(&p->p_lwp_tree, lwp_id) == NULL) {
407 lwkt_reltoken(&p->p_token);
411 *clock_id = MAKE_CPUCLOCK(pid, lwp_id);
412 lwkt_reltoken(&p->p_token);
419 sys_getcpuclockid(struct getcpuclockid_args *uap)
424 error = kern_getcpuclockid(uap->pid, uap->lwp_id, &clk_id);
426 error = copyout(&clk_id, uap->clock_id, sizeof(clockid_t));
434 * This is a general helper function for nanosleep() (aka sleep() aka
437 * If there is less then one tick's worth of time left and
438 * we haven't done a yield, or the remaining microseconds is
439 * ridiculously low, do a yield. This avoids having
440 * to deal with systimer overheads when the system is under
441 * heavy loads. If we have done a yield already then use
442 * a systimer and an uninterruptable thread wait.
444 * If there is more then a tick's worth of time left,
445 * calculate the baseline ticks and use an interruptable
446 * tsleep, then handle the fine-grained delay on the next
447 * loop. This usually results in two sleeps occuring, a long one
453 ns1_systimer(systimer_t info, int in_ipi __unused,
454 struct intrframe *frame __unused)
456 lwkt_schedule(info->data);
460 nanosleep1(struct timespec *rqt, struct timespec *rmt)
463 struct timespec ts, ts2, ts3;
467 if (rqt->tv_nsec < 0 || rqt->tv_nsec >= 1000000000)
469 /* XXX: imho this should return EINVAL at least for tv_sec < 0 */
470 if (rqt->tv_sec < 0 || (rqt->tv_sec == 0 && rqt->tv_nsec == 0))
473 timespecadd(&ts, rqt); /* ts = target timestamp compare */
474 TIMESPEC_TO_TIMEVAL(&tv, rqt); /* tv = sleep interval */
478 struct systimer info;
480 ticks = tv.tv_usec / ustick; /* approximate */
482 if (tv.tv_sec == 0 && ticks == 0) {
483 thread_t td = curthread;
484 if (tv.tv_usec > 0 && tv.tv_usec < nanosleep_min_us)
485 tv.tv_usec = nanosleep_min_us;
486 if (tv.tv_usec < nanosleep_hard_us) {
490 crit_enter_quick(td);
491 systimer_init_oneshot(&info, ns1_systimer,
493 lwkt_deschedule_self(td);
496 systimer_del(&info); /* make sure it's gone */
498 error = iscaught(td->td_lwp);
499 } else if (tv.tv_sec == 0) {
500 error = tsleep(&nanowait, PCATCH, "nanslp", ticks);
502 ticks = tvtohz_low(&tv); /* also handles overflow */
503 error = tsleep(&nanowait, PCATCH, "nanslp", ticks);
506 if (error && error != EWOULDBLOCK) {
507 if (error == ERESTART)
510 timespecsub(&ts, &ts2);
517 if (timespeccmp(&ts2, &ts, >=))
520 timespecsub(&ts3, &ts2);
521 TIMESPEC_TO_TIMEVAL(&tv, &ts3);
529 sys_nanosleep(struct nanosleep_args *uap)
535 error = copyin(uap->rqtp, &rqt, sizeof(rqt));
539 error = nanosleep1(&rqt, &rmt);
542 * copyout the residual if nanosleep was interrupted.
544 if (error && uap->rmtp) {
547 error2 = copyout(&rmt, uap->rmtp, sizeof(rmt));
555 * The gettimeofday() system call is supposed to return a fine-grained
556 * realtime stamp. However, acquiring a fine-grained stamp can create a
557 * bottleneck when multiple cpu cores are trying to accessing e.g. the
558 * HPET hardware timer all at the same time, so we have a sysctl that
559 * allows its behavior to be changed to a more coarse-grained timestamp
560 * which does not have to access a hardware timer.
563 sys_gettimeofday(struct gettimeofday_args *uap)
569 if (gettimeofday_quick)
573 if ((error = copyout((caddr_t)&atv, (caddr_t)uap->tp,
578 error = copyout((caddr_t)&tz, (caddr_t)uap->tzp,
587 sys_settimeofday(struct settimeofday_args *uap)
589 struct thread *td = curthread;
594 if ((error = priv_check(td, PRIV_SETTIMEOFDAY)))
597 * Verify all parameters before changing time.
599 * XXX: We do not allow the time to be set to 0.0, which also by
600 * happy coincidence works around a pkgsrc bulk build bug.
603 if ((error = copyin((caddr_t)uap->tv, (caddr_t)&atv,
606 if (atv.tv_usec < 0 || atv.tv_usec >= 1000000)
608 if (atv.tv_sec == 0 && atv.tv_usec == 0)
612 (error = copyin((caddr_t)uap->tzp, (caddr_t)&atz, sizeof(atz))))
615 lockmgr(&masterclock_lock, LK_EXCLUSIVE);
616 if (uap->tv && (error = settime(&atv))) {
617 lockmgr(&masterclock_lock, LK_RELEASE);
620 lockmgr(&masterclock_lock, LK_RELEASE);
628 * WARNING! Run with ntp_spin held
631 kern_adjtime_common(void)
633 if ((ntp_delta >= 0 && ntp_delta < ntp_default_tick_delta) ||
634 (ntp_delta < 0 && ntp_delta > -ntp_default_tick_delta))
635 ntp_tick_delta = ntp_delta;
636 else if (ntp_delta > ntp_big_delta)
637 ntp_tick_delta = 10 * ntp_default_tick_delta;
638 else if (ntp_delta < -ntp_big_delta)
639 ntp_tick_delta = -10 * ntp_default_tick_delta;
640 else if (ntp_delta > 0)
641 ntp_tick_delta = ntp_default_tick_delta;
643 ntp_tick_delta = -ntp_default_tick_delta;
647 kern_adjtime(int64_t delta, int64_t *odelta)
649 spin_lock(&ntp_spin);
652 kern_adjtime_common();
653 spin_unlock(&ntp_spin);
657 kern_get_ntp_delta(int64_t *delta)
663 kern_reladjtime(int64_t delta)
665 spin_lock(&ntp_spin);
667 kern_adjtime_common();
668 spin_unlock(&ntp_spin);
672 kern_adjfreq(int64_t rate)
674 spin_lock(&ntp_spin);
675 ntp_tick_permanent = rate;
676 spin_unlock(&ntp_spin);
683 sys_adjtime(struct adjtime_args *uap)
685 struct thread *td = curthread;
687 int64_t ndelta, odelta;
690 if ((error = priv_check(td, PRIV_ADJTIME)))
692 error = copyin(uap->delta, &atv, sizeof(struct timeval));
697 * Compute the total correction and the rate at which to apply it.
698 * Round the adjustment down to a whole multiple of the per-tick
699 * delta, so that after some number of incremental changes in
700 * hardclock(), tickdelta will become zero, lest the correction
701 * overshoot and start taking us away from the desired final time.
703 ndelta = (int64_t)atv.tv_sec * 1000000000 + atv.tv_usec * 1000;
704 kern_adjtime(ndelta, &odelta);
707 atv.tv_sec = odelta / 1000000000;
708 atv.tv_usec = odelta % 1000000000 / 1000;
709 copyout(&atv, uap->olddelta, sizeof(struct timeval));
715 sysctl_adjtime(SYSCTL_HANDLER_ARGS)
720 if (req->newptr != NULL) {
721 if (priv_check(curthread, PRIV_ROOT))
723 error = SYSCTL_IN(req, &delta, sizeof(delta));
726 kern_reladjtime(delta);
730 kern_get_ntp_delta(&delta);
731 error = SYSCTL_OUT(req, &delta, sizeof(delta));
736 * delta is in nanoseconds.
739 sysctl_delta(SYSCTL_HANDLER_ARGS)
741 int64_t delta, old_delta;
744 if (req->newptr != NULL) {
745 if (priv_check(curthread, PRIV_ROOT))
747 error = SYSCTL_IN(req, &delta, sizeof(delta));
750 kern_adjtime(delta, &old_delta);
753 if (req->oldptr != NULL)
754 kern_get_ntp_delta(&old_delta);
755 error = SYSCTL_OUT(req, &old_delta, sizeof(old_delta));
760 * frequency is in nanoseconds per second shifted left 32.
761 * kern_adjfreq() needs it in nanoseconds per tick shifted left 32.
764 sysctl_adjfreq(SYSCTL_HANDLER_ARGS)
769 if (req->newptr != NULL) {
770 if (priv_check(curthread, PRIV_ROOT))
772 error = SYSCTL_IN(req, &freqdelta, sizeof(freqdelta));
777 kern_adjfreq(freqdelta);
780 if (req->oldptr != NULL)
781 freqdelta = ntp_tick_permanent * hz;
782 error = SYSCTL_OUT(req, &freqdelta, sizeof(freqdelta));
789 SYSCTL_NODE(_kern, OID_AUTO, ntp, CTLFLAG_RW, 0, "NTP related controls");
790 SYSCTL_PROC(_kern_ntp, OID_AUTO, permanent,
791 CTLTYPE_QUAD|CTLFLAG_RW, 0, 0,
792 sysctl_adjfreq, "Q", "permanent correction per second");
793 SYSCTL_PROC(_kern_ntp, OID_AUTO, delta,
794 CTLTYPE_QUAD|CTLFLAG_RW, 0, 0,
795 sysctl_delta, "Q", "one-time delta");
796 SYSCTL_OPAQUE(_kern_ntp, OID_AUTO, big_delta, CTLFLAG_RD,
797 &ntp_big_delta, sizeof(ntp_big_delta), "Q",
798 "threshold for fast adjustment");
799 SYSCTL_OPAQUE(_kern_ntp, OID_AUTO, tick_delta, CTLFLAG_RD,
800 &ntp_tick_delta, sizeof(ntp_tick_delta), "LU",
801 "per-tick adjustment");
802 SYSCTL_OPAQUE(_kern_ntp, OID_AUTO, default_tick_delta, CTLFLAG_RD,
803 &ntp_default_tick_delta, sizeof(ntp_default_tick_delta), "LU",
804 "default per-tick adjustment");
805 SYSCTL_OPAQUE(_kern_ntp, OID_AUTO, next_leap_second, CTLFLAG_RW,
806 &ntp_leap_second, sizeof(ntp_leap_second), "LU",
808 SYSCTL_INT(_kern_ntp, OID_AUTO, insert_leap_second, CTLFLAG_RW,
809 &ntp_leap_insert, 0, "insert or remove leap second");
810 SYSCTL_PROC(_kern_ntp, OID_AUTO, adjust,
811 CTLTYPE_QUAD|CTLFLAG_RW, 0, 0,
812 sysctl_adjtime, "Q", "relative adjust for delta");
815 * Get value of an interval timer. The process virtual and
816 * profiling virtual time timers are kept in the p_stats area, since
817 * they can be swapped out. These are kept internally in the
818 * way they are specified externally: in time until they expire.
820 * The real time interval timer is kept in the process table slot
821 * for the process, and its value (it_value) is kept as an
822 * absolute time rather than as a delta, so that it is easy to keep
823 * periodic real-time signals from drifting.
825 * Virtual time timers are processed in the hardclock() routine of
826 * kern_clock.c. The real time timer is processed by a timeout
827 * routine, called from the softclock() routine. Since a callout
828 * may be delayed in real time due to interrupt processing in the system,
829 * it is possible for the real time timeout routine (realitexpire, given below),
830 * to be delayed in real time past when it is supposed to occur. It
831 * does not suffice, therefore, to reload the real timer .it_value from the
832 * real time timers .it_interval. Rather, we compute the next time in
833 * absolute time the timer should go off.
838 sys_getitimer(struct getitimer_args *uap)
840 struct proc *p = curproc;
842 struct itimerval aitv;
844 if (uap->which > ITIMER_PROF)
846 lwkt_gettoken(&p->p_token);
847 if (uap->which == ITIMER_REAL) {
849 * Convert from absolute to relative time in .it_value
850 * part of real time timer. If time for real time timer
851 * has passed return 0, else return difference between
852 * current time and time for the timer to go off.
854 aitv = p->p_realtimer;
855 if (timevalisset(&aitv.it_value)) {
856 getmicrouptime(&ctv);
857 if (timevalcmp(&aitv.it_value, &ctv, <))
858 timevalclear(&aitv.it_value);
860 timevalsub(&aitv.it_value, &ctv);
863 aitv = p->p_timer[uap->which];
865 lwkt_reltoken(&p->p_token);
866 return (copyout(&aitv, uap->itv, sizeof (struct itimerval)));
873 sys_setitimer(struct setitimer_args *uap)
875 struct itimerval aitv;
877 struct itimerval *itvp;
878 struct proc *p = curproc;
881 if (uap->which > ITIMER_PROF)
884 if (itvp && (error = copyin((caddr_t)itvp, (caddr_t)&aitv,
885 sizeof(struct itimerval))))
887 if ((uap->itv = uap->oitv) &&
888 (error = sys_getitimer((struct getitimer_args *)uap)))
892 if (itimerfix(&aitv.it_value))
894 if (!timevalisset(&aitv.it_value))
895 timevalclear(&aitv.it_interval);
896 else if (itimerfix(&aitv.it_interval))
898 lwkt_gettoken(&p->p_token);
899 if (uap->which == ITIMER_REAL) {
900 if (timevalisset(&p->p_realtimer.it_value))
901 callout_stop_sync(&p->p_ithandle);
902 if (timevalisset(&aitv.it_value))
903 callout_reset(&p->p_ithandle,
904 tvtohz_high(&aitv.it_value), realitexpire, p);
905 getmicrouptime(&ctv);
906 timevaladd(&aitv.it_value, &ctv);
907 p->p_realtimer = aitv;
909 p->p_timer[uap->which] = aitv;
912 p->p_flags &= ~P_SIGVTALRM;
915 p->p_flags &= ~P_SIGPROF;
919 lwkt_reltoken(&p->p_token);
924 * Real interval timer expired:
925 * send process whose timer expired an alarm signal.
926 * If time is not set up to reload, then just return.
927 * Else compute next time timer should go off which is > current time.
928 * This is where delay in processing this timeout causes multiple
929 * SIGALRM calls to be compressed into one.
930 * tvtohz_high() always adds 1 to allow for the time until the next clock
931 * interrupt being strictly less than 1 clock tick, but we don't want
932 * that here since we want to appear to be in sync with the clock
933 * interrupt even when we're delayed.
937 realitexpire(void *arg)
940 struct timeval ctv, ntv;
942 p = (struct proc *)arg;
944 lwkt_gettoken(&p->p_token);
946 if (!timevalisset(&p->p_realtimer.it_interval)) {
947 timevalclear(&p->p_realtimer.it_value);
951 timevaladd(&p->p_realtimer.it_value,
952 &p->p_realtimer.it_interval);
953 getmicrouptime(&ctv);
954 if (timevalcmp(&p->p_realtimer.it_value, &ctv, >)) {
955 ntv = p->p_realtimer.it_value;
956 timevalsub(&ntv, &ctv);
957 callout_reset(&p->p_ithandle, tvtohz_low(&ntv),
963 lwkt_reltoken(&p->p_token);
968 * Used to validate itimer timeouts and utimes*() timespecs.
971 itimerfix(struct timeval *tv)
973 if (tv->tv_sec < 0 || tv->tv_usec < 0 || tv->tv_usec >= 1000000)
975 if (tv->tv_sec == 0 && tv->tv_usec != 0 && tv->tv_usec < ustick)
976 tv->tv_usec = ustick;
981 * Used to validate timeouts and utimes*() timespecs.
984 itimespecfix(struct timespec *ts)
986 if (ts->tv_sec < 0 || ts->tv_nsec < 0 || ts->tv_nsec >= 1000000000ULL)
988 if (ts->tv_sec == 0 && ts->tv_nsec != 0 && ts->tv_nsec < nstick)
989 ts->tv_nsec = nstick;
994 * Decrement an interval timer by a specified number
995 * of microseconds, which must be less than a second,
996 * i.e. < 1000000. If the timer expires, then reload
997 * it. In this case, carry over (usec - old value) to
998 * reduce the value reloaded into the timer so that
999 * the timer does not drift. This routine assumes
1000 * that it is called in a context where the timers
1001 * on which it is operating cannot change in value.
1004 itimerdecr(struct itimerval *itp, int usec)
1007 if (itp->it_value.tv_usec < usec) {
1008 if (itp->it_value.tv_sec == 0) {
1009 /* expired, and already in next interval */
1010 usec -= itp->it_value.tv_usec;
1013 itp->it_value.tv_usec += 1000000;
1014 itp->it_value.tv_sec--;
1016 itp->it_value.tv_usec -= usec;
1018 if (timevalisset(&itp->it_value))
1020 /* expired, exactly at end of interval */
1022 if (timevalisset(&itp->it_interval)) {
1023 itp->it_value = itp->it_interval;
1024 itp->it_value.tv_usec -= usec;
1025 if (itp->it_value.tv_usec < 0) {
1026 itp->it_value.tv_usec += 1000000;
1027 itp->it_value.tv_sec--;
1030 itp->it_value.tv_usec = 0; /* sec is already 0 */
1035 * Add and subtract routines for timevals.
1036 * N.B.: subtract routine doesn't deal with
1037 * results which are before the beginning,
1038 * it just gets very confused in this case.
1042 timevaladd(struct timeval *t1, const struct timeval *t2)
1045 t1->tv_sec += t2->tv_sec;
1046 t1->tv_usec += t2->tv_usec;
1051 timevalsub(struct timeval *t1, const struct timeval *t2)
1054 t1->tv_sec -= t2->tv_sec;
1055 t1->tv_usec -= t2->tv_usec;
1060 timevalfix(struct timeval *t1)
1063 if (t1->tv_usec < 0) {
1065 t1->tv_usec += 1000000;
1067 if (t1->tv_usec >= 1000000) {
1069 t1->tv_usec -= 1000000;
1074 * ratecheck(): simple time-based rate-limit checking.
1077 ratecheck(struct timeval *lasttime, const struct timeval *mininterval)
1079 struct timeval tv, delta;
1082 getmicrouptime(&tv); /* NB: 10ms precision */
1084 timevalsub(&delta, lasttime);
1087 * check for 0,0 is so that the message will be seen at least once,
1088 * even if interval is huge.
1090 if (timevalcmp(&delta, mininterval, >=) ||
1091 (lasttime->tv_sec == 0 && lasttime->tv_usec == 0)) {
1100 * ppsratecheck(): packets (or events) per second limitation.
1102 * Return 0 if the limit is to be enforced (e.g. the caller
1103 * should drop a packet because of the rate limitation).
1105 * maxpps of 0 always causes zero to be returned. maxpps of -1
1106 * always causes 1 to be returned; this effectively defeats rate
1109 * Note that we maintain the struct timeval for compatibility
1110 * with other bsd systems. We reuse the storage and just monitor
1111 * clock ticks for minimal overhead.
1114 ppsratecheck(struct timeval *lasttime, int *curpps, int maxpps)
1119 * Reset the last time and counter if this is the first call
1120 * or more than a second has passed since the last update of
1124 if (lasttime->tv_sec == 0 || (u_int)(now - lasttime->tv_sec) >= hz) {
1125 lasttime->tv_sec = now;
1127 return (maxpps != 0);
1129 (*curpps)++; /* NB: ignore potential overflow */
1130 return (maxpps < 0 || *curpps < maxpps);