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kern_time.c revision 1.146.2.7
      1 /*	$NetBSD: kern_time.c,v 1.146.2.7 2008/06/30 23:03:38 wrstuden Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2000, 2004, 2005, 2007, 2008 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Christopher G. Demetriou.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Copyright (c) 1982, 1986, 1989, 1993
     34  *	The Regents of the University of California.  All rights reserved.
     35  *
     36  * Redistribution and use in source and binary forms, with or without
     37  * modification, are permitted provided that the following conditions
     38  * are met:
     39  * 1. Redistributions of source code must retain the above copyright
     40  *    notice, this list of conditions and the following disclaimer.
     41  * 2. Redistributions in binary form must reproduce the above copyright
     42  *    notice, this list of conditions and the following disclaimer in the
     43  *    documentation and/or other materials provided with the distribution.
     44  * 3. Neither the name of the University nor the names of its contributors
     45  *    may be used to endorse or promote products derived from this software
     46  *    without specific prior written permission.
     47  *
     48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     58  * SUCH DAMAGE.
     59  *
     60  *	@(#)kern_time.c	8.4 (Berkeley) 5/26/95
     61  */
     62 
     63 #include <sys/cdefs.h>
     64 __KERNEL_RCSID(0, "$NetBSD: kern_time.c,v 1.146.2.7 2008/06/30 23:03:38 wrstuden Exp $");
     65 
     66 #include <sys/param.h>
     67 #include <sys/resourcevar.h>
     68 #include <sys/kernel.h>
     69 #include <sys/systm.h>
     70 #include <sys/proc.h>
     71 #include <sys/vnode.h>
     72 #include <sys/signalvar.h>
     73 #include <sys/syslog.h>
     74 #include <sys/timetc.h>
     75 #include <sys/timex.h>
     76 #include <sys/kauth.h>
     77 #include <sys/mount.h>
     78 #include <sys/sa.h>
     79 #include <sys/savar.h>
     80 #include <sys/syscallargs.h>
     81 #include <sys/cpu.h>
     82 
     83 #include <uvm/uvm_extern.h>
     84 
     85 static void	timer_intr(void *);
     86 static void	itimerfire(struct ptimer *);
     87 static void	itimerfree(struct ptimers *, int);
     88 
     89 kmutex_t	timer_lock;
     90 
     91 static void	*timer_sih;
     92 static TAILQ_HEAD(, ptimer) timer_queue;
     93 
     94 POOL_INIT(ptimer_pool, sizeof(struct ptimer), 0, 0, 0, "ptimerpl",
     95     &pool_allocator_nointr, IPL_NONE);
     96 POOL_INIT(ptimers_pool, sizeof(struct ptimers), 0, 0, 0, "ptimerspl",
     97     &pool_allocator_nointr, IPL_NONE);
     98 
     99 /*
    100  * Initialize timekeeping.
    101  */
    102 void
    103 time_init(void)
    104 {
    105 
    106 	/* nothing yet */
    107 }
    108 
    109 void
    110 time_init2(void)
    111 {
    112 
    113 	TAILQ_INIT(&timer_queue);
    114 	mutex_init(&timer_lock, MUTEX_DEFAULT, IPL_SCHED);
    115 	timer_sih = softint_establish(SOFTINT_CLOCK | SOFTINT_MPSAFE,
    116 	    timer_intr, NULL);
    117 }
    118 
    119 /* Time of day and interval timer support.
    120  *
    121  * These routines provide the kernel entry points to get and set
    122  * the time-of-day and per-process interval timers.  Subroutines
    123  * here provide support for adding and subtracting timeval structures
    124  * and decrementing interval timers, optionally reloading the interval
    125  * timers when they expire.
    126  */
    127 
    128 /* This function is used by clock_settime and settimeofday */
    129 static int
    130 settime1(struct proc *p, struct timespec *ts, bool check_kauth)
    131 {
    132 	struct timeval delta, tv;
    133 	struct timeval now;
    134 	struct timespec ts1;
    135 	struct bintime btdelta;
    136 	lwp_t *l;
    137 	int s;
    138 
    139 	TIMESPEC_TO_TIMEVAL(&tv, ts);
    140 
    141 	/* WHAT DO WE DO ABOUT PENDING REAL-TIME TIMEOUTS??? */
    142 	s = splclock();
    143 	microtime(&now);
    144 	timersub(&tv, &now, &delta);
    145 
    146 	if (check_kauth && kauth_authorize_system(kauth_cred_get(),
    147 	    KAUTH_SYSTEM_TIME, KAUTH_REQ_SYSTEM_TIME_SYSTEM, ts, &delta,
    148 	    KAUTH_ARG(check_kauth ? false : true)) != 0) {
    149 		splx(s);
    150 		return (EPERM);
    151 	}
    152 
    153 #ifdef notyet
    154 	if ((delta.tv_sec < 86400) && securelevel > 0) { /* XXX elad - notyet */
    155 		splx(s);
    156 		return (EPERM);
    157 	}
    158 #endif
    159 
    160 	TIMEVAL_TO_TIMESPEC(&tv, &ts1);
    161 	tc_setclock(&ts1);
    162 
    163 	timeradd(&boottime, &delta, &boottime);
    164 
    165 	/*
    166 	 * XXXSMP: There is a short race between setting the time above
    167 	 * and adjusting LWP's run times.  Fixing this properly means
    168 	 * pausing all CPUs while we adjust the clock.
    169 	 */
    170 	timeval2bintime(&delta, &btdelta);
    171 	mutex_enter(proc_lock);
    172 	LIST_FOREACH(l, &alllwp, l_list) {
    173 		lwp_lock(l);
    174 		bintime_add(&l->l_stime, &btdelta);
    175 		lwp_unlock(l);
    176 	}
    177 	mutex_exit(proc_lock);
    178 	resettodr();
    179 	splx(s);
    180 
    181 	return (0);
    182 }
    183 
    184 int
    185 settime(struct proc *p, struct timespec *ts)
    186 {
    187 	return (settime1(p, ts, true));
    188 }
    189 
    190 /* ARGSUSED */
    191 int
    192 sys_clock_gettime(struct lwp *l, const struct sys_clock_gettime_args *uap,
    193     register_t *retval)
    194 {
    195 	/* {
    196 		syscallarg(clockid_t) clock_id;
    197 		syscallarg(struct timespec *) tp;
    198 	} */
    199 	clockid_t clock_id;
    200 	struct timespec ats;
    201 
    202 	clock_id = SCARG(uap, clock_id);
    203 	switch (clock_id) {
    204 	case CLOCK_REALTIME:
    205 		nanotime(&ats);
    206 		break;
    207 	case CLOCK_MONOTONIC:
    208 		nanouptime(&ats);
    209 		break;
    210 	default:
    211 		return (EINVAL);
    212 	}
    213 
    214 	return copyout(&ats, SCARG(uap, tp), sizeof(ats));
    215 }
    216 
    217 /* ARGSUSED */
    218 int
    219 sys_clock_settime(struct lwp *l, const struct sys_clock_settime_args *uap,
    220     register_t *retval)
    221 {
    222 	/* {
    223 		syscallarg(clockid_t) clock_id;
    224 		syscallarg(const struct timespec *) tp;
    225 	} */
    226 
    227 	return clock_settime1(l->l_proc, SCARG(uap, clock_id), SCARG(uap, tp),
    228 	    true);
    229 }
    230 
    231 
    232 int
    233 clock_settime1(struct proc *p, clockid_t clock_id, const struct timespec *tp,
    234     bool check_kauth)
    235 {
    236 	struct timespec ats;
    237 	int error;
    238 
    239 	if ((error = copyin(tp, &ats, sizeof(ats))) != 0)
    240 		return (error);
    241 
    242 	switch (clock_id) {
    243 	case CLOCK_REALTIME:
    244 		if ((error = settime1(p, &ats, check_kauth)) != 0)
    245 			return (error);
    246 		break;
    247 	case CLOCK_MONOTONIC:
    248 		return (EINVAL);	/* read-only clock */
    249 	default:
    250 		return (EINVAL);
    251 	}
    252 
    253 	return 0;
    254 }
    255 
    256 int
    257 sys_clock_getres(struct lwp *l, const struct sys_clock_getres_args *uap,
    258     register_t *retval)
    259 {
    260 	/* {
    261 		syscallarg(clockid_t) clock_id;
    262 		syscallarg(struct timespec *) tp;
    263 	} */
    264 	clockid_t clock_id;
    265 	struct timespec ts;
    266 	int error = 0;
    267 
    268 	clock_id = SCARG(uap, clock_id);
    269 	switch (clock_id) {
    270 	case CLOCK_REALTIME:
    271 	case CLOCK_MONOTONIC:
    272 		ts.tv_sec = 0;
    273 		if (tc_getfrequency() > 1000000000)
    274 			ts.tv_nsec = 1;
    275 		else
    276 			ts.tv_nsec = 1000000000 / tc_getfrequency();
    277 		break;
    278 	default:
    279 		return (EINVAL);
    280 	}
    281 
    282 	if (SCARG(uap, tp))
    283 		error = copyout(&ts, SCARG(uap, tp), sizeof(ts));
    284 
    285 	return error;
    286 }
    287 
    288 /* ARGSUSED */
    289 int
    290 sys_nanosleep(struct lwp *l, const struct sys_nanosleep_args *uap,
    291     register_t *retval)
    292 {
    293 	/* {
    294 		syscallarg(struct timespec *) rqtp;
    295 		syscallarg(struct timespec *) rmtp;
    296 	} */
    297 	struct timespec rmt, rqt;
    298 	int error, error1;
    299 
    300 	error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec));
    301 	if (error)
    302 		return (error);
    303 
    304 	error = nanosleep1(l, &rqt, SCARG(uap, rmtp) ? &rmt : NULL);
    305 	if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR))
    306 		return error;
    307 
    308 	error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt));
    309 	return error1 ? error1 : error;
    310 }
    311 
    312 int
    313 nanosleep1(struct lwp *l, struct timespec *rqt, struct timespec *rmt)
    314 {
    315 	struct timespec rmtstart;
    316 	int error, timo;
    317 
    318 	if (itimespecfix(rqt))
    319 		return (EINVAL);
    320 
    321 	timo = tstohz(rqt);
    322 	/*
    323 	 * Avoid inadvertantly sleeping forever
    324 	 */
    325 	if (timo == 0)
    326 		timo = 1;
    327 	getnanouptime(&rmtstart);
    328 again:
    329 	error = kpause("nanoslp", true, timo, NULL);
    330 	if (rmt != NULL || error == 0) {
    331 		struct timespec rmtend;
    332 		struct timespec t0;
    333 		struct timespec *t;
    334 
    335 		getnanouptime(&rmtend);
    336 		t = (rmt != NULL) ? rmt : &t0;
    337 		timespecsub(&rmtend, &rmtstart, t);
    338 		timespecsub(rqt, t, t);
    339 		if (t->tv_sec < 0)
    340 			timespecclear(t);
    341 		if (error == 0) {
    342 			timo = tstohz(t);
    343 			if (timo > 0)
    344 				goto again;
    345 		}
    346 	}
    347 
    348 	if (error == ERESTART)
    349 		error = EINTR;
    350 	if (error == EWOULDBLOCK)
    351 		error = 0;
    352 
    353 	return error;
    354 }
    355 
    356 /* ARGSUSED */
    357 int
    358 sys_gettimeofday(struct lwp *l, const struct sys_gettimeofday_args *uap,
    359     register_t *retval)
    360 {
    361 	/* {
    362 		syscallarg(struct timeval *) tp;
    363 		syscallarg(void *) tzp;		really "struct timezone *";
    364 	} */
    365 	struct timeval atv;
    366 	int error = 0;
    367 	struct timezone tzfake;
    368 
    369 	if (SCARG(uap, tp)) {
    370 		microtime(&atv);
    371 		error = copyout(&atv, SCARG(uap, tp), sizeof(atv));
    372 		if (error)
    373 			return (error);
    374 	}
    375 	if (SCARG(uap, tzp)) {
    376 		/*
    377 		 * NetBSD has no kernel notion of time zone, so we just
    378 		 * fake up a timezone struct and return it if demanded.
    379 		 */
    380 		tzfake.tz_minuteswest = 0;
    381 		tzfake.tz_dsttime = 0;
    382 		error = copyout(&tzfake, SCARG(uap, tzp), sizeof(tzfake));
    383 	}
    384 	return (error);
    385 }
    386 
    387 /* ARGSUSED */
    388 int
    389 sys_settimeofday(struct lwp *l, const struct sys_settimeofday_args *uap,
    390     register_t *retval)
    391 {
    392 	/* {
    393 		syscallarg(const struct timeval *) tv;
    394 		syscallarg(const void *) tzp; really "const struct timezone *";
    395 	} */
    396 
    397 	return settimeofday1(SCARG(uap, tv), true, SCARG(uap, tzp), l, true);
    398 }
    399 
    400 int
    401 settimeofday1(const struct timeval *utv, bool userspace,
    402     const void *utzp, struct lwp *l, bool check_kauth)
    403 {
    404 	struct timeval atv;
    405 	struct timespec ts;
    406 	int error;
    407 
    408 	/* Verify all parameters before changing time. */
    409 
    410 	/*
    411 	 * NetBSD has no kernel notion of time zone, and only an
    412 	 * obsolete program would try to set it, so we log a warning.
    413 	 */
    414 	if (utzp)
    415 		log(LOG_WARNING, "pid %d attempted to set the "
    416 		    "(obsolete) kernel time zone\n", l->l_proc->p_pid);
    417 
    418 	if (utv == NULL)
    419 		return 0;
    420 
    421 	if (userspace) {
    422 		if ((error = copyin(utv, &atv, sizeof(atv))) != 0)
    423 			return error;
    424 		utv = &atv;
    425 	}
    426 
    427 	TIMEVAL_TO_TIMESPEC(utv, &ts);
    428 	return settime1(l->l_proc, &ts, check_kauth);
    429 }
    430 
    431 int	time_adjusted;			/* set if an adjustment is made */
    432 
    433 /* ARGSUSED */
    434 int
    435 sys_adjtime(struct lwp *l, const struct sys_adjtime_args *uap,
    436     register_t *retval)
    437 {
    438 	/* {
    439 		syscallarg(const struct timeval *) delta;
    440 		syscallarg(struct timeval *) olddelta;
    441 	} */
    442 	int error;
    443 
    444 	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_TIME,
    445 	    KAUTH_REQ_SYSTEM_TIME_ADJTIME, NULL, NULL, NULL)) != 0)
    446 		return (error);
    447 
    448 	return adjtime1(SCARG(uap, delta), SCARG(uap, olddelta), l->l_proc);
    449 }
    450 
    451 int
    452 adjtime1(const struct timeval *delta, struct timeval *olddelta, struct proc *p)
    453 {
    454 	struct timeval atv;
    455 	int error = 0;
    456 
    457 	extern int64_t time_adjtime;  /* in kern_ntptime.c */
    458 
    459 	if (olddelta) {
    460 		mutex_spin_enter(&timecounter_lock);
    461 		atv.tv_sec = time_adjtime / 1000000;
    462 		atv.tv_usec = time_adjtime % 1000000;
    463 		mutex_spin_exit(&timecounter_lock);
    464 		if (atv.tv_usec < 0) {
    465 			atv.tv_usec += 1000000;
    466 			atv.tv_sec--;
    467 		}
    468 		error = copyout(&atv, olddelta, sizeof(struct timeval));
    469 		if (error)
    470 			return (error);
    471 	}
    472 
    473 	if (delta) {
    474 		error = copyin(delta, &atv, sizeof(struct timeval));
    475 		if (error)
    476 			return (error);
    477 
    478 		mutex_spin_enter(&timecounter_lock);
    479 		time_adjtime = (int64_t)atv.tv_sec * 1000000 +
    480 			atv.tv_usec;
    481 		if (time_adjtime) {
    482 			/* We need to save the system time during shutdown */
    483 			time_adjusted |= 1;
    484 		}
    485 		mutex_spin_exit(&timecounter_lock);
    486 	}
    487 
    488 	return error;
    489 }
    490 
    491 /*
    492  * Interval timer support. Both the BSD getitimer() family and the POSIX
    493  * timer_*() family of routines are supported.
    494  *
    495  * All timers are kept in an array pointed to by p_timers, which is
    496  * allocated on demand - many processes don't use timers at all. The
    497  * first three elements in this array are reserved for the BSD timers:
    498  * element 0 is ITIMER_REAL, element 1 is ITIMER_VIRTUAL, and element
    499  * 2 is ITIMER_PROF. The rest may be allocated by the timer_create()
    500  * syscall.
    501  *
    502  * Realtime timers are kept in the ptimer structure as an absolute
    503  * time; virtual time timers are kept as a linked list of deltas.
    504  * Virtual time timers are processed in the hardclock() routine of
    505  * kern_clock.c.  The real time timer is processed by a callout
    506  * routine, called from the softclock() routine.  Since a callout may
    507  * be delayed in real time due to interrupt processing in the system,
    508  * it is possible for the real time timeout routine (realtimeexpire,
    509  * given below), to be delayed in real time past when it is supposed
    510  * to occur.  It does not suffice, therefore, to reload the real timer
    511  * .it_value from the real time timers .it_interval.  Rather, we
    512  * compute the next time in absolute time the timer should go off.  */
    513 
    514 /* Allocate a POSIX realtime timer. */
    515 int
    516 sys_timer_create(struct lwp *l, const struct sys_timer_create_args *uap,
    517     register_t *retval)
    518 {
    519 	/* {
    520 		syscallarg(clockid_t) clock_id;
    521 		syscallarg(struct sigevent *) evp;
    522 		syscallarg(timer_t *) timerid;
    523 	} */
    524 
    525 	return timer_create1(SCARG(uap, timerid), SCARG(uap, clock_id),
    526 	    SCARG(uap, evp), copyin, l);
    527 }
    528 
    529 int
    530 timer_create1(timer_t *tid, clockid_t id, struct sigevent *evp,
    531     copyin_t fetch_event, struct lwp *l)
    532 {
    533 	int error;
    534 	timer_t timerid;
    535 	struct ptimers *pts;
    536 	struct ptimer *pt;
    537 	struct proc *p;
    538 
    539 	p = l->l_proc;
    540 
    541 	if (id < CLOCK_REALTIME || id > CLOCK_PROF)
    542 		return (EINVAL);
    543 
    544 	if ((pts = p->p_timers) == NULL)
    545 		pts = timers_alloc(p);
    546 
    547 	pt = pool_get(&ptimer_pool, PR_WAITOK);
    548 	if (evp != NULL) {
    549 		if (((error =
    550 		    (*fetch_event)(evp, &pt->pt_ev, sizeof(pt->pt_ev))) != 0) ||
    551 		    ((pt->pt_ev.sigev_notify < SIGEV_NONE) ||
    552 			(pt->pt_ev.sigev_notify > SIGEV_SA))) {
    553 			pool_put(&ptimer_pool, pt);
    554 			return (error ? error : EINVAL);
    555 		}
    556 	}
    557 
    558 	/* Find a free timer slot, skipping those reserved for setitimer(). */
    559 	mutex_spin_enter(&timer_lock);
    560 	for (timerid = 3; timerid < TIMER_MAX; timerid++)
    561 		if (pts->pts_timers[timerid] == NULL)
    562 			break;
    563 	if (timerid == TIMER_MAX) {
    564 		mutex_spin_exit(&timer_lock);
    565 		pool_put(&ptimer_pool, pt);
    566 		return EAGAIN;
    567 	}
    568 	if (evp == NULL) {
    569 		pt->pt_ev.sigev_notify = SIGEV_SIGNAL;
    570 		switch (id) {
    571 		case CLOCK_REALTIME:
    572 			pt->pt_ev.sigev_signo = SIGALRM;
    573 			break;
    574 		case CLOCK_VIRTUAL:
    575 			pt->pt_ev.sigev_signo = SIGVTALRM;
    576 			break;
    577 		case CLOCK_PROF:
    578 			pt->pt_ev.sigev_signo = SIGPROF;
    579 			break;
    580 		}
    581 		pt->pt_ev.sigev_value.sival_int = timerid;
    582 	}
    583 	pt->pt_info.ksi_signo = pt->pt_ev.sigev_signo;
    584 	pt->pt_info.ksi_errno = 0;
    585 	pt->pt_info.ksi_code = 0;
    586 	pt->pt_info.ksi_pid = p->p_pid;
    587 	pt->pt_info.ksi_uid = kauth_cred_getuid(l->l_cred);
    588 	pt->pt_info.ksi_value = pt->pt_ev.sigev_value;
    589 	pt->pt_type = id;
    590 	pt->pt_proc = p;
    591 	pt->pt_overruns = 0;
    592 	pt->pt_poverruns = 0;
    593 	pt->pt_entry = timerid;
    594 	pt->pt_queued = false;
    595 	pt->pt_active = 0;
    596 	timerclear(&pt->pt_time.it_value);
    597 	callout_init(&pt->pt_ch, 0);
    598 	pts->pts_timers[timerid] = pt;
    599 	mutex_spin_exit(&timer_lock);
    600 
    601 	return copyout(&timerid, tid, sizeof(timerid));
    602 }
    603 
    604 /* Delete a POSIX realtime timer */
    605 int
    606 sys_timer_delete(struct lwp *l, const struct sys_timer_delete_args *uap,
    607     register_t *retval)
    608 {
    609 	/* {
    610 		syscallarg(timer_t) timerid;
    611 	} */
    612 	struct proc *p = l->l_proc;
    613 	timer_t timerid;
    614 	struct ptimers *pts;
    615 	struct ptimer *pt, *ptn;
    616 
    617 	timerid = SCARG(uap, timerid);
    618 	pts = p->p_timers;
    619 
    620 	if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
    621 		return (EINVAL);
    622 
    623 	mutex_spin_enter(&timer_lock);
    624 	if ((pt = pts->pts_timers[timerid]) == NULL) {
    625 		mutex_spin_exit(&timer_lock);
    626 		return (EINVAL);
    627 	}
    628 	if (pt->pt_active) {
    629 		ptn = LIST_NEXT(pt, pt_list);
    630 		LIST_REMOVE(pt, pt_list);
    631 		for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list))
    632 			timeradd(&pt->pt_time.it_value, &ptn->pt_time.it_value,
    633 			    &ptn->pt_time.it_value);
    634 		pt->pt_active = 0;
    635 	}
    636 	itimerfree(pts, timerid);
    637 
    638 	return (0);
    639 }
    640 
    641 /*
    642  * Set up the given timer. The value in pt->pt_time.it_value is taken
    643  * to be an absolute time for CLOCK_REALTIME timers and a relative
    644  * time for virtual timers.
    645  * Must be called at splclock().
    646  */
    647 void
    648 timer_settime(struct ptimer *pt)
    649 {
    650 	struct ptimer *ptn, *pptn;
    651 	struct ptlist *ptl;
    652 
    653 	KASSERT(mutex_owned(&timer_lock));
    654 
    655 	if (pt->pt_type == CLOCK_REALTIME) {
    656 		callout_stop(&pt->pt_ch);
    657 		if (timerisset(&pt->pt_time.it_value)) {
    658 			/*
    659 			 * Don't need to check hzto() return value, here.
    660 			 * callout_reset() does it for us.
    661 			 */
    662 			callout_reset(&pt->pt_ch, hzto(&pt->pt_time.it_value),
    663 			    realtimerexpire, pt);
    664 		}
    665 	} else {
    666 		if (pt->pt_active) {
    667 			ptn = LIST_NEXT(pt, pt_list);
    668 			LIST_REMOVE(pt, pt_list);
    669 			for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list))
    670 				timeradd(&pt->pt_time.it_value,
    671 				    &ptn->pt_time.it_value,
    672 				    &ptn->pt_time.it_value);
    673 		}
    674 		if (timerisset(&pt->pt_time.it_value)) {
    675 			if (pt->pt_type == CLOCK_VIRTUAL)
    676 				ptl = &pt->pt_proc->p_timers->pts_virtual;
    677 			else
    678 				ptl = &pt->pt_proc->p_timers->pts_prof;
    679 
    680 			for (ptn = LIST_FIRST(ptl), pptn = NULL;
    681 			     ptn && timercmp(&pt->pt_time.it_value,
    682 				 &ptn->pt_time.it_value, >);
    683 			     pptn = ptn, ptn = LIST_NEXT(ptn, pt_list))
    684 				timersub(&pt->pt_time.it_value,
    685 				    &ptn->pt_time.it_value,
    686 				    &pt->pt_time.it_value);
    687 
    688 			if (pptn)
    689 				LIST_INSERT_AFTER(pptn, pt, pt_list);
    690 			else
    691 				LIST_INSERT_HEAD(ptl, pt, pt_list);
    692 
    693 			for ( ; ptn ; ptn = LIST_NEXT(ptn, pt_list))
    694 				timersub(&ptn->pt_time.it_value,
    695 				    &pt->pt_time.it_value,
    696 				    &ptn->pt_time.it_value);
    697 
    698 			pt->pt_active = 1;
    699 		} else
    700 			pt->pt_active = 0;
    701 	}
    702 }
    703 
    704 void
    705 timer_gettime(struct ptimer *pt, struct itimerval *aitv)
    706 {
    707 	struct timeval now;
    708 	struct ptimer *ptn;
    709 
    710 	KASSERT(mutex_owned(&timer_lock));
    711 
    712 	*aitv = pt->pt_time;
    713 	if (pt->pt_type == CLOCK_REALTIME) {
    714 		/*
    715 		 * Convert from absolute to relative time in .it_value
    716 		 * part of real time timer.  If time for real time
    717 		 * timer has passed return 0, else return difference
    718 		 * between current time and time for the timer to go
    719 		 * off.
    720 		 */
    721 		if (timerisset(&aitv->it_value)) {
    722 			getmicrotime(&now);
    723 			if (timercmp(&aitv->it_value, &now, <))
    724 				timerclear(&aitv->it_value);
    725 			else
    726 				timersub(&aitv->it_value, &now,
    727 				    &aitv->it_value);
    728 		}
    729 	} else if (pt->pt_active) {
    730 		if (pt->pt_type == CLOCK_VIRTUAL)
    731 			ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_virtual);
    732 		else
    733 			ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_prof);
    734 		for ( ; ptn && ptn != pt; ptn = LIST_NEXT(ptn, pt_list))
    735 			timeradd(&aitv->it_value,
    736 			    &ptn->pt_time.it_value, &aitv->it_value);
    737 		KASSERT(ptn != NULL); /* pt should be findable on the list */
    738 	} else
    739 		timerclear(&aitv->it_value);
    740 }
    741 
    742 
    743 
    744 /* Set and arm a POSIX realtime timer */
    745 int
    746 sys_timer_settime(struct lwp *l, const struct sys_timer_settime_args *uap,
    747     register_t *retval)
    748 {
    749 	/* {
    750 		syscallarg(timer_t) timerid;
    751 		syscallarg(int) flags;
    752 		syscallarg(const struct itimerspec *) value;
    753 		syscallarg(struct itimerspec *) ovalue;
    754 	} */
    755 	int error;
    756 	struct itimerspec value, ovalue, *ovp = NULL;
    757 
    758 	if ((error = copyin(SCARG(uap, value), &value,
    759 	    sizeof(struct itimerspec))) != 0)
    760 		return (error);
    761 
    762 	if (SCARG(uap, ovalue))
    763 		ovp = &ovalue;
    764 
    765 	if ((error = dotimer_settime(SCARG(uap, timerid), &value, ovp,
    766 	    SCARG(uap, flags), l->l_proc)) != 0)
    767 		return error;
    768 
    769 	if (ovp)
    770 		return copyout(&ovalue, SCARG(uap, ovalue),
    771 		    sizeof(struct itimerspec));
    772 	return 0;
    773 }
    774 
    775 int
    776 dotimer_settime(int timerid, struct itimerspec *value,
    777     struct itimerspec *ovalue, int flags, struct proc *p)
    778 {
    779 	struct timeval now;
    780 	struct itimerval val, oval;
    781 	struct ptimers *pts;
    782 	struct ptimer *pt;
    783 
    784 	pts = p->p_timers;
    785 
    786 	if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
    787 		return EINVAL;
    788 	TIMESPEC_TO_TIMEVAL(&val.it_value, &value->it_value);
    789 	TIMESPEC_TO_TIMEVAL(&val.it_interval, &value->it_interval);
    790 	if (itimerfix(&val.it_value) || itimerfix(&val.it_interval))
    791 		return (EINVAL);
    792 
    793 	mutex_spin_enter(&timer_lock);
    794 	if ((pt = pts->pts_timers[timerid]) == NULL) {
    795 		mutex_spin_exit(&timer_lock);
    796 		return (EINVAL);
    797 	}
    798 
    799 	oval = pt->pt_time;
    800 	pt->pt_time = val;
    801 
    802 	/*
    803 	 * If we've been passed a relative time for a realtime timer,
    804 	 * convert it to absolute; if an absolute time for a virtual
    805 	 * timer, convert it to relative and make sure we don't set it
    806 	 * to zero, which would cancel the timer, or let it go
    807 	 * negative, which would confuse the comparison tests.
    808 	 */
    809 	if (timerisset(&pt->pt_time.it_value)) {
    810 		if (pt->pt_type == CLOCK_REALTIME) {
    811 			if ((flags & TIMER_ABSTIME) == 0) {
    812 				getmicrotime(&now);
    813 				timeradd(&pt->pt_time.it_value, &now,
    814 				    &pt->pt_time.it_value);
    815 			}
    816 		} else {
    817 			if ((flags & TIMER_ABSTIME) != 0) {
    818 				getmicrotime(&now);
    819 				timersub(&pt->pt_time.it_value, &now,
    820 				    &pt->pt_time.it_value);
    821 				if (!timerisset(&pt->pt_time.it_value) ||
    822 				    pt->pt_time.it_value.tv_sec < 0) {
    823 					pt->pt_time.it_value.tv_sec = 0;
    824 					pt->pt_time.it_value.tv_usec = 1;
    825 				}
    826 			}
    827 		}
    828 	}
    829 
    830 	timer_settime(pt);
    831 	mutex_spin_exit(&timer_lock);
    832 
    833 	if (ovalue) {
    834 		TIMEVAL_TO_TIMESPEC(&oval.it_value, &ovalue->it_value);
    835 		TIMEVAL_TO_TIMESPEC(&oval.it_interval, &ovalue->it_interval);
    836 	}
    837 
    838 	return (0);
    839 }
    840 
    841 /* Return the time remaining until a POSIX timer fires. */
    842 int
    843 sys_timer_gettime(struct lwp *l, const struct sys_timer_gettime_args *uap,
    844     register_t *retval)
    845 {
    846 	/* {
    847 		syscallarg(timer_t) timerid;
    848 		syscallarg(struct itimerspec *) value;
    849 	} */
    850 	struct itimerspec its;
    851 	int error;
    852 
    853 	if ((error = dotimer_gettime(SCARG(uap, timerid), l->l_proc,
    854 	    &its)) != 0)
    855 		return error;
    856 
    857 	return copyout(&its, SCARG(uap, value), sizeof(its));
    858 }
    859 
    860 int
    861 dotimer_gettime(int timerid, struct proc *p, struct itimerspec *its)
    862 {
    863 	struct ptimer *pt;
    864 	struct ptimers *pts;
    865 	struct itimerval aitv;
    866 
    867 	pts = p->p_timers;
    868 	if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
    869 		return (EINVAL);
    870 	mutex_spin_enter(&timer_lock);
    871 	if ((pt = pts->pts_timers[timerid]) == NULL) {
    872 		mutex_spin_exit(&timer_lock);
    873 		return (EINVAL);
    874 	}
    875 	timer_gettime(pt, &aitv);
    876 	mutex_spin_exit(&timer_lock);
    877 
    878 	TIMEVAL_TO_TIMESPEC(&aitv.it_interval, &its->it_interval);
    879 	TIMEVAL_TO_TIMESPEC(&aitv.it_value, &its->it_value);
    880 
    881 	return 0;
    882 }
    883 
    884 /*
    885  * Return the count of the number of times a periodic timer expired
    886  * while a notification was already pending. The counter is reset when
    887  * a timer expires and a notification can be posted.
    888  */
    889 int
    890 sys_timer_getoverrun(struct lwp *l, const struct sys_timer_getoverrun_args *uap,
    891     register_t *retval)
    892 {
    893 	/* {
    894 		syscallarg(timer_t) timerid;
    895 	} */
    896 	struct proc *p = l->l_proc;
    897 	struct ptimers *pts;
    898 	int timerid;
    899 	struct ptimer *pt;
    900 
    901 	timerid = SCARG(uap, timerid);
    902 
    903 	pts = p->p_timers;
    904 	if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX)
    905 		return (EINVAL);
    906 	mutex_spin_enter(&timer_lock);
    907 	if ((pt = pts->pts_timers[timerid]) == NULL) {
    908 		mutex_spin_exit(&timer_lock);
    909 		return (EINVAL);
    910 	}
    911 	*retval = pt->pt_poverruns;
    912 	mutex_spin_exit(&timer_lock);
    913 
    914 	return (0);
    915 }
    916 
    917 /* Glue function that triggers an upcall; called from userret(). */
    918 void
    919 timerupcall(struct lwp *l)
    920 {
    921 	struct ptimers *pt = l->l_proc->p_timers;
    922 	struct proc *p = l->l_proc;
    923 	unsigned int i, fired, done;
    924 
    925 	KDASSERT(l->l_proc->p_sa);
    926 	/* Bail out if we do not own the virtual processor */
    927 	if (l->l_savp->savp_lwp != l)
    928 		return ;
    929 
    930 	mutex_enter(p->p_lock);
    931 
    932 	fired = pt->pts_fired;
    933 	done = 0;
    934 	while ((i = ffs(fired)) != 0) {
    935 		siginfo_t *si;
    936 		int mask = 1 << --i;
    937 		int f;
    938 
    939 		f = ~l->l_pflag & LP_SA_NOBLOCK;
    940 		l->l_pflag |= LP_SA_NOBLOCK;
    941 		si = siginfo_alloc(PR_WAITOK);
    942 		si->_info = pt->pts_timers[i]->pt_info.ksi_info;
    943 		if (sa_upcall(l, SA_UPCALL_SIGEV | SA_UPCALL_DEFER, NULL, l,
    944 		    sizeof(*si), si, siginfo_free) != 0) {
    945 			siginfo_free(si);
    946 			/* XXX What do we do here?? */
    947 		} else
    948 			done |= mask;
    949 		fired &= ~mask;
    950 		l->l_pflag ^= f;
    951 	}
    952 	pt->pts_fired &= ~done;
    953 	if (pt->pts_fired == 0)
    954 		l->l_proc->p_timerpend = 0;
    955 
    956 	mutex_exit(p->p_lock);
    957 }
    958 
    959 /*
    960  * Real interval timer expired:
    961  * send process whose timer expired an alarm signal.
    962  * If time is not set up to reload, then just return.
    963  * Else compute next time timer should go off which is > current time.
    964  * This is where delay in processing this timeout causes multiple
    965  * SIGALRM calls to be compressed into one.
    966  */
    967 void
    968 realtimerexpire(void *arg)
    969 {
    970 	uint64_t last_val, next_val, interval, now_ms;
    971 	struct timeval now, next;
    972 	struct ptimer *pt;
    973 	int backwards;
    974 
    975 	pt = arg;
    976 
    977 	mutex_spin_enter(&timer_lock);
    978 	itimerfire(pt);
    979 
    980 	if (!timerisset(&pt->pt_time.it_interval)) {
    981 		timerclear(&pt->pt_time.it_value);
    982 		mutex_spin_exit(&timer_lock);
    983 		return;
    984 	}
    985 
    986 	getmicrotime(&now);
    987 	backwards = (timercmp(&pt->pt_time.it_value, &now, >));
    988 	timeradd(&pt->pt_time.it_value, &pt->pt_time.it_interval, &next);
    989 	/* Handle the easy case of non-overflown timers first. */
    990 	if (!backwards && timercmp(&next, &now, >)) {
    991 		pt->pt_time.it_value = next;
    992 	} else {
    993 #define TV2MS(x) (((uint64_t)(x)->tv_sec) * 1000000 + (x)->tv_usec)
    994 		now_ms = TV2MS(&now);
    995 		last_val = TV2MS(&pt->pt_time.it_value);
    996 		interval = TV2MS(&pt->pt_time.it_interval);
    997 #undef TV2MS
    998 
    999 		next_val = now_ms +
   1000 		    (now_ms - last_val + interval - 1) % interval;
   1001 
   1002 		if (backwards)
   1003 			next_val += interval;
   1004 		else
   1005 			pt->pt_overruns += (now_ms - last_val) / interval;
   1006 
   1007 		pt->pt_time.it_value.tv_sec = next_val / 1000000;
   1008 		pt->pt_time.it_value.tv_usec = next_val % 1000000;
   1009 	}
   1010 
   1011 	/*
   1012 	 * Don't need to check hzto() return value, here.
   1013 	 * callout_reset() does it for us.
   1014 	 */
   1015 	callout_reset(&pt->pt_ch, hzto(&pt->pt_time.it_value),
   1016 	    realtimerexpire, pt);
   1017 	mutex_spin_exit(&timer_lock);
   1018 }
   1019 
   1020 /* BSD routine to get the value of an interval timer. */
   1021 /* ARGSUSED */
   1022 int
   1023 sys_getitimer(struct lwp *l, const struct sys_getitimer_args *uap,
   1024     register_t *retval)
   1025 {
   1026 	/* {
   1027 		syscallarg(int) which;
   1028 		syscallarg(struct itimerval *) itv;
   1029 	} */
   1030 	struct proc *p = l->l_proc;
   1031 	struct itimerval aitv;
   1032 	int error;
   1033 
   1034 	error = dogetitimer(p, SCARG(uap, which), &aitv);
   1035 	if (error)
   1036 		return error;
   1037 	return (copyout(&aitv, SCARG(uap, itv), sizeof(struct itimerval)));
   1038 }
   1039 
   1040 int
   1041 dogetitimer(struct proc *p, int which, struct itimerval *itvp)
   1042 {
   1043 	struct ptimers *pts;
   1044 	struct ptimer *pt;
   1045 
   1046 	if ((u_int)which > ITIMER_PROF)
   1047 		return (EINVAL);
   1048 
   1049 	mutex_spin_enter(&timer_lock);
   1050 	pts = p->p_timers;
   1051 	if (pts == NULL || (pt = pts->pts_timers[which]) == NULL) {
   1052 		timerclear(&itvp->it_value);
   1053 		timerclear(&itvp->it_interval);
   1054 	} else
   1055 		timer_gettime(pt, itvp);
   1056 	mutex_spin_exit(&timer_lock);
   1057 
   1058 	return 0;
   1059 }
   1060 
   1061 /* BSD routine to set/arm an interval timer. */
   1062 /* ARGSUSED */
   1063 int
   1064 sys_setitimer(struct lwp *l, const struct sys_setitimer_args *uap,
   1065     register_t *retval)
   1066 {
   1067 	/* {
   1068 		syscallarg(int) which;
   1069 		syscallarg(const struct itimerval *) itv;
   1070 		syscallarg(struct itimerval *) oitv;
   1071 	} */
   1072 	struct proc *p = l->l_proc;
   1073 	int which = SCARG(uap, which);
   1074 	struct sys_getitimer_args getargs;
   1075 	const struct itimerval *itvp;
   1076 	struct itimerval aitv;
   1077 	int error;
   1078 
   1079 	if ((u_int)which > ITIMER_PROF)
   1080 		return (EINVAL);
   1081 	itvp = SCARG(uap, itv);
   1082 	if (itvp &&
   1083 	    (error = copyin(itvp, &aitv, sizeof(struct itimerval)) != 0))
   1084 		return (error);
   1085 	if (SCARG(uap, oitv) != NULL) {
   1086 		SCARG(&getargs, which) = which;
   1087 		SCARG(&getargs, itv) = SCARG(uap, oitv);
   1088 		if ((error = sys_getitimer(l, &getargs, retval)) != 0)
   1089 			return (error);
   1090 	}
   1091 	if (itvp == 0)
   1092 		return (0);
   1093 
   1094 	return dosetitimer(p, which, &aitv);
   1095 }
   1096 
   1097 int
   1098 dosetitimer(struct proc *p, int which, struct itimerval *itvp)
   1099 {
   1100 	struct timeval now;
   1101 	struct ptimers *pts;
   1102 	struct ptimer *pt, *spare;
   1103 
   1104 	if (itimerfix(&itvp->it_value) || itimerfix(&itvp->it_interval))
   1105 		return (EINVAL);
   1106 
   1107 	/*
   1108 	 * Don't bother allocating data structures if the process just
   1109 	 * wants to clear the timer.
   1110 	 */
   1111 	spare = NULL;
   1112 	pts = p->p_timers;
   1113  retry:
   1114 	if (!timerisset(&itvp->it_value) && (pts == NULL ||
   1115 	    pts->pts_timers[which] == NULL))
   1116 		return (0);
   1117 	if (pts == NULL)
   1118 		pts = timers_alloc(p);
   1119 	mutex_spin_enter(&timer_lock);
   1120 	pt = pts->pts_timers[which];
   1121 	if (pt == NULL) {
   1122 		if (spare == NULL) {
   1123 			mutex_spin_exit(&timer_lock);
   1124 			spare = pool_get(&ptimer_pool, PR_WAITOK);
   1125 			goto retry;
   1126 		}
   1127 		pt = spare;
   1128 		spare = NULL;
   1129 		pt->pt_ev.sigev_notify = SIGEV_SIGNAL;
   1130 		pt->pt_ev.sigev_value.sival_int = which;
   1131 		pt->pt_overruns = 0;
   1132 		pt->pt_proc = p;
   1133 		pt->pt_type = which;
   1134 		pt->pt_entry = which;
   1135 		pt->pt_active = 0;
   1136 		pt->pt_queued = false;
   1137 		callout_init(&pt->pt_ch, CALLOUT_MPSAFE);
   1138 		switch (which) {
   1139 		case ITIMER_REAL:
   1140 			pt->pt_ev.sigev_signo = SIGALRM;
   1141 			break;
   1142 		case ITIMER_VIRTUAL:
   1143 			pt->pt_ev.sigev_signo = SIGVTALRM;
   1144 			break;
   1145 		case ITIMER_PROF:
   1146 			pt->pt_ev.sigev_signo = SIGPROF;
   1147 			break;
   1148 		}
   1149 		pts->pts_timers[which] = pt;
   1150 	}
   1151 	pt->pt_time = *itvp;
   1152 
   1153 	if ((which == ITIMER_REAL) && timerisset(&pt->pt_time.it_value)) {
   1154 		/* Convert to absolute time */
   1155 		/* XXX need to wrap in splclock for timecounters case? */
   1156 		getmicrotime(&now);
   1157 		timeradd(&pt->pt_time.it_value, &now, &pt->pt_time.it_value);
   1158 	}
   1159 	timer_settime(pt);
   1160 	mutex_spin_exit(&timer_lock);
   1161 	if (spare != NULL)
   1162 		pool_put(&ptimer_pool, spare);
   1163 
   1164 	return (0);
   1165 }
   1166 
   1167 /* Utility routines to manage the array of pointers to timers. */
   1168 struct ptimers *
   1169 timers_alloc(struct proc *p)
   1170 {
   1171 	struct ptimers *pts;
   1172 	int i;
   1173 
   1174 	pts = pool_get(&ptimers_pool, PR_WAITOK);
   1175 	LIST_INIT(&pts->pts_virtual);
   1176 	LIST_INIT(&pts->pts_prof);
   1177 	for (i = 0; i < TIMER_MAX; i++)
   1178 		pts->pts_timers[i] = NULL;
   1179 	pts->pts_fired = 0;
   1180 	mutex_spin_enter(&timer_lock);
   1181 	if (p->p_timers == NULL) {
   1182 		p->p_timers = pts;
   1183 		mutex_spin_exit(&timer_lock);
   1184 		return pts;
   1185 	}
   1186 	mutex_spin_exit(&timer_lock);
   1187 	pool_put(&ptimers_pool, pts);
   1188 	return p->p_timers;
   1189 }
   1190 
   1191 /*
   1192  * Clean up the per-process timers. If "which" is set to TIMERS_ALL,
   1193  * then clean up all timers and free all the data structures. If
   1194  * "which" is set to TIMERS_POSIX, only clean up the timers allocated
   1195  * by timer_create(), not the BSD setitimer() timers, and only free the
   1196  * structure if none of those remain.
   1197  */
   1198 void
   1199 timers_free(struct proc *p, int which)
   1200 {
   1201 	struct ptimers *pts;
   1202 	struct ptimer *ptn;
   1203 	struct timeval tv;
   1204 	int i;
   1205 
   1206 	if (p->p_timers == NULL)
   1207 		return;
   1208 
   1209 	pts = p->p_timers;
   1210 	mutex_spin_enter(&timer_lock);
   1211 	if (which == TIMERS_ALL) {
   1212 		p->p_timers = NULL;
   1213 		i = 0;
   1214 	} else {
   1215 		timerclear(&tv);
   1216 		for (ptn = LIST_FIRST(&pts->pts_virtual);
   1217 		     ptn && ptn != pts->pts_timers[ITIMER_VIRTUAL];
   1218 		     ptn = LIST_NEXT(ptn, pt_list))
   1219 			timeradd(&tv, &ptn->pt_time.it_value, &tv);
   1220 		LIST_FIRST(&pts->pts_virtual) = NULL;
   1221 		if (ptn) {
   1222 			timeradd(&tv, &ptn->pt_time.it_value,
   1223 			    &ptn->pt_time.it_value);
   1224 			LIST_INSERT_HEAD(&pts->pts_virtual, ptn, pt_list);
   1225 		}
   1226 		timerclear(&tv);
   1227 		for (ptn = LIST_FIRST(&pts->pts_prof);
   1228 		     ptn && ptn != pts->pts_timers[ITIMER_PROF];
   1229 		     ptn = LIST_NEXT(ptn, pt_list))
   1230 			timeradd(&tv, &ptn->pt_time.it_value, &tv);
   1231 		LIST_FIRST(&pts->pts_prof) = NULL;
   1232 		if (ptn) {
   1233 			timeradd(&tv, &ptn->pt_time.it_value,
   1234 			    &ptn->pt_time.it_value);
   1235 			LIST_INSERT_HEAD(&pts->pts_prof, ptn, pt_list);
   1236 		}
   1237 		i = 3;
   1238 	}
   1239 	for ( ; i < TIMER_MAX; i++) {
   1240 		if (pts->pts_timers[i] != NULL) {
   1241 			itimerfree(pts, i);
   1242 			mutex_spin_enter(&timer_lock);
   1243 		}
   1244 	}
   1245 	if (pts->pts_timers[0] == NULL && pts->pts_timers[1] == NULL &&
   1246 	    pts->pts_timers[2] == NULL) {
   1247 		p->p_timers = NULL;
   1248 		mutex_spin_exit(&timer_lock);
   1249 		pool_put(&ptimers_pool, pts);
   1250 	} else
   1251 		mutex_spin_exit(&timer_lock);
   1252 }
   1253 
   1254 static void
   1255 itimerfree(struct ptimers *pts, int index)
   1256 {
   1257 	struct ptimer *pt;
   1258 
   1259 	KASSERT(mutex_owned(&timer_lock));
   1260 
   1261 	pt = pts->pts_timers[index];
   1262 	pts->pts_timers[index] = NULL;
   1263 	if (pt->pt_type == CLOCK_REALTIME)
   1264 		callout_halt(&pt->pt_ch, &timer_lock);
   1265 	else if (pt->pt_queued)
   1266 		TAILQ_REMOVE(&timer_queue, pt, pt_chain);
   1267 	mutex_spin_exit(&timer_lock);
   1268 	callout_destroy(&pt->pt_ch);
   1269 	pool_put(&ptimer_pool, pt);
   1270 }
   1271 
   1272 /*
   1273  * Decrement an interval timer by a specified number
   1274  * of microseconds, which must be less than a second,
   1275  * i.e. < 1000000.  If the timer expires, then reload
   1276  * it.  In this case, carry over (usec - old value) to
   1277  * reduce the value reloaded into the timer so that
   1278  * the timer does not drift.  This routine assumes
   1279  * that it is called in a context where the timers
   1280  * on which it is operating cannot change in value.
   1281  */
   1282 static int
   1283 itimerdecr(struct ptimer *pt, int usec)
   1284 {
   1285 	struct itimerval *itp;
   1286 
   1287 	KASSERT(mutex_owned(&timer_lock));
   1288 
   1289 	itp = &pt->pt_time;
   1290 	if (itp->it_value.tv_usec < usec) {
   1291 		if (itp->it_value.tv_sec == 0) {
   1292 			/* expired, and already in next interval */
   1293 			usec -= itp->it_value.tv_usec;
   1294 			goto expire;
   1295 		}
   1296 		itp->it_value.tv_usec += 1000000;
   1297 		itp->it_value.tv_sec--;
   1298 	}
   1299 	itp->it_value.tv_usec -= usec;
   1300 	usec = 0;
   1301 	if (timerisset(&itp->it_value))
   1302 		return (1);
   1303 	/* expired, exactly at end of interval */
   1304 expire:
   1305 	if (timerisset(&itp->it_interval)) {
   1306 		itp->it_value = itp->it_interval;
   1307 		itp->it_value.tv_usec -= usec;
   1308 		if (itp->it_value.tv_usec < 0) {
   1309 			itp->it_value.tv_usec += 1000000;
   1310 			itp->it_value.tv_sec--;
   1311 		}
   1312 		timer_settime(pt);
   1313 	} else
   1314 		itp->it_value.tv_usec = 0;		/* sec is already 0 */
   1315 	return (0);
   1316 }
   1317 
   1318 static void
   1319 itimerfire(struct ptimer *pt)
   1320 {
   1321 
   1322 	KASSERT(mutex_owned(&timer_lock));
   1323 
   1324 	/*
   1325 	 * XXX Can overrun, but we don't do signal queueing yet, anyway.
   1326 	 * XXX Relying on the clock interrupt is stupid.
   1327 	 */
   1328 	if ((pt->pt_ev.sigev_notify == SIGEV_SA && pt->pt_proc->p_sa == NULL) ||
   1329 	    (pt->pt_ev.sigev_notify != SIGEV_SIGNAL &&
   1330 	    pt->pt_ev.sigev_notify != SIGEV_SA) || pt->pt_queued)
   1331 		return;
   1332 	TAILQ_INSERT_TAIL(&timer_queue, pt, pt_chain);
   1333 	pt->pt_queued = true;
   1334 	softint_schedule(timer_sih);
   1335 }
   1336 
   1337 void
   1338 timer_tick(lwp_t *l, bool user)
   1339 {
   1340 	struct ptimers *pts;
   1341 	struct ptimer *pt;
   1342 	proc_t *p;
   1343 
   1344 	p = l->l_proc;
   1345 	if (p->p_timers == NULL)
   1346 		return;
   1347 
   1348 	mutex_spin_enter(&timer_lock);
   1349 	if ((pts = l->l_proc->p_timers) != NULL) {
   1350 		/*
   1351 		 * Run current process's virtual and profile time, as needed.
   1352 		 */
   1353 		if (user && (pt = LIST_FIRST(&pts->pts_virtual)) != NULL)
   1354 			if (itimerdecr(pt, tick) == 0)
   1355 				itimerfire(pt);
   1356 		if ((pt = LIST_FIRST(&pts->pts_prof)) != NULL)
   1357 			if (itimerdecr(pt, tick) == 0)
   1358 				itimerfire(pt);
   1359 	}
   1360 	mutex_spin_exit(&timer_lock);
   1361 }
   1362 
   1363 /*
   1364  * timer_sa_intr:
   1365  *
   1366  *	SIGEV_SA handling for timer_intr(). We are called (and return)
   1367  * with the timer lock held. We know that the process had SA enabled
   1368  * when this timer was enqueued. As timer_intr() is a soft interrupt
   1369  * handler, SA should still be enabled by the time we get here.
   1370  *
   1371  * XXX Is it legit to lock p_lock and the lwp at this time?
   1372  */
   1373 static void
   1374 timer_sa_intr(struct ptimer *pt, proc_t *p)
   1375 {
   1376 	unsigned int i;
   1377 	struct sadata_vp *vp;
   1378 
   1379 	/* Cause the process to generate an upcall when it returns. */
   1380 	if (!p->p_timerpend) {
   1381 		/*
   1382 		 * XXX stop signals can be processed inside tsleep,
   1383 		 * which can be inside sa_yield's inner loop, which
   1384 		 * makes testing for sa_idle alone insuffucent to
   1385 		 * determine if we really should call setrunnable.
   1386 		 */
   1387 		pt->pt_poverruns = pt->pt_overruns;
   1388 		pt->pt_overruns = 0;
   1389 		i = 1 << pt->pt_entry;
   1390 		p->p_timers->pts_fired = i;
   1391 		p->p_timerpend = 1;
   1392 
   1393 		mutex_enter(p->p_lock);
   1394 		SLIST_FOREACH(vp, &p->p_sa->sa_vps, savp_next) {
   1395 			lwp_lock(vp->savp_lwp);
   1396 			lwp_need_userret(vp->savp_lwp);
   1397 			if (vp->savp_lwp->l_flag & LW_SA_IDLE) {
   1398 				vp->savp_lwp->l_flag &= ~LW_SA_IDLE;
   1399 				lwp_unsleep(vp->savp_lwp, true);
   1400 				break;
   1401 			}
   1402 			lwp_unlock(vp->savp_lwp);
   1403 		}
   1404 		mutex_exit(p->p_lock);
   1405 	} else {
   1406 		i = 1 << pt->pt_entry;
   1407 		if ((p->p_timers->pts_fired & i) == 0) {
   1408 			pt->pt_poverruns = pt->pt_overruns;
   1409 			pt->pt_overruns = 0;
   1410 			p->p_timers->pts_fired |= i;
   1411 		} else
   1412 			pt->pt_overruns++;
   1413 	}
   1414 }
   1415 
   1416 static void
   1417 timer_intr(void *cookie)
   1418 {
   1419 	ksiginfo_t ksi;
   1420 	struct ptimer *pt;
   1421 	proc_t *p;
   1422 
   1423 	mutex_spin_enter(&timer_lock);
   1424 	while ((pt = TAILQ_FIRST(&timer_queue)) != NULL) {
   1425 		TAILQ_REMOVE(&timer_queue, pt, pt_chain);
   1426 		KASSERT(pt->pt_queued);
   1427 		pt->pt_queued = false;
   1428 
   1429 		if (pt->pt_proc->p_timers == NULL) {
   1430 			/* Process is dying. */
   1431 			continue;
   1432 		}
   1433 		p = pt->pt_proc;
   1434 		if (pt->pt_ev.sigev_notify == SIGEV_SA) {
   1435 			timer_sa_intr(pt, p);
   1436 			continue;
   1437 		}
   1438 		if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL)
   1439 			continue;
   1440 		if (sigismember(&p->p_sigpend.sp_set, pt->pt_ev.sigev_signo)) {
   1441 			pt->pt_overruns++;
   1442 			continue;
   1443 		}
   1444 
   1445 		KSI_INIT(&ksi);
   1446 		ksi.ksi_signo = pt->pt_ev.sigev_signo;
   1447 		ksi.ksi_code = SI_TIMER;
   1448 		ksi.ksi_value = pt->pt_ev.sigev_value;
   1449 		pt->pt_poverruns = pt->pt_overruns;
   1450 		pt->pt_overruns = 0;
   1451 		mutex_spin_exit(&timer_lock);
   1452 
   1453 		mutex_enter(proc_lock);
   1454 		kpsignal(p, &ksi, NULL);
   1455 		mutex_exit(proc_lock);
   1456 
   1457 		mutex_spin_enter(&timer_lock);
   1458 	}
   1459 	mutex_spin_exit(&timer_lock);
   1460 }
   1461 
   1462 /*
   1463  * ratecheck(): simple time-based rate-limit checking.  see ratecheck(9)
   1464  * for usage and rationale.
   1465  */
   1466 int
   1467 ratecheck(struct timeval *lasttime, const struct timeval *mininterval)
   1468 {
   1469 	struct timeval tv, delta;
   1470 	int rv = 0;
   1471 
   1472 	getmicrouptime(&tv);
   1473 	timersub(&tv, lasttime, &delta);
   1474 
   1475 	/*
   1476 	 * check for 0,0 is so that the message will be seen at least once,
   1477 	 * even if interval is huge.
   1478 	 */
   1479 	if (timercmp(&delta, mininterval, >=) ||
   1480 	    (lasttime->tv_sec == 0 && lasttime->tv_usec == 0)) {
   1481 		*lasttime = tv;
   1482 		rv = 1;
   1483 	}
   1484 
   1485 	return (rv);
   1486 }
   1487 
   1488 /*
   1489  * ppsratecheck(): packets (or events) per second limitation.
   1490  */
   1491 int
   1492 ppsratecheck(struct timeval *lasttime, int *curpps, int maxpps)
   1493 {
   1494 	struct timeval tv, delta;
   1495 	int rv;
   1496 
   1497 	getmicrouptime(&tv);
   1498 	timersub(&tv, lasttime, &delta);
   1499 
   1500 	/*
   1501 	 * check for 0,0 is so that the message will be seen at least once.
   1502 	 * if more than one second have passed since the last update of
   1503 	 * lasttime, reset the counter.
   1504 	 *
   1505 	 * we do increment *curpps even in *curpps < maxpps case, as some may
   1506 	 * try to use *curpps for stat purposes as well.
   1507 	 */
   1508 	if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) ||
   1509 	    delta.tv_sec >= 1) {
   1510 		*lasttime = tv;
   1511 		*curpps = 0;
   1512 	}
   1513 	if (maxpps < 0)
   1514 		rv = 1;
   1515 	else if (*curpps < maxpps)
   1516 		rv = 1;
   1517 	else
   1518 		rv = 0;
   1519 
   1520 #if 1 /*DIAGNOSTIC?*/
   1521 	/* be careful about wrap-around */
   1522 	if (*curpps + 1 > *curpps)
   1523 		*curpps = *curpps + 1;
   1524 #else
   1525 	/*
   1526 	 * assume that there's not too many calls to this function.
   1527 	 * not sure if the assumption holds, as it depends on *caller's*
   1528 	 * behavior, not the behavior of this function.
   1529 	 * IMHO it is wrong to make assumption on the caller's behavior,
   1530 	 * so the above #if is #if 1, not #ifdef DIAGNOSTIC.
   1531 	 */
   1532 	*curpps = *curpps + 1;
   1533 #endif
   1534 
   1535 	return (rv);
   1536 }
   1537