1 /* $NetBSD: kern_time.c,v 1.148 2008/05/29 15:27:51 joerg 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 1.148 2008/05/29 15:27:51 joerg 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/syscallargs.h> 79 #include <sys/cpu.h> 80 81 #include <uvm/uvm_extern.h> 82 83 static void timer_intr(void *); 84 static void itimerfire(struct ptimer *); 85 static void itimerfree(struct ptimers *, int); 86 87 kmutex_t timer_lock; 88 89 static void *timer_sih; 90 static TAILQ_HEAD(, ptimer) timer_queue; 91 92 POOL_INIT(ptimer_pool, sizeof(struct ptimer), 0, 0, 0, "ptimerpl", 93 &pool_allocator_nointr, IPL_NONE); 94 POOL_INIT(ptimers_pool, sizeof(struct ptimers), 0, 0, 0, "ptimerspl", 95 &pool_allocator_nointr, IPL_NONE); 96 97 /* 98 * Initialize timekeeping. 99 */ 100 void 101 time_init(void) 102 { 103 104 /* nothing yet */ 105 } 106 107 void 108 time_init2(void) 109 { 110 111 TAILQ_INIT(&timer_queue); 112 mutex_init(&timer_lock, MUTEX_DEFAULT, IPL_SCHED); 113 timer_sih = softint_establish(SOFTINT_CLOCK | SOFTINT_MPSAFE, 114 timer_intr, NULL); 115 } 116 117 /* Time of day and interval timer support. 118 * 119 * These routines provide the kernel entry points to get and set 120 * the time-of-day and per-process interval timers. Subroutines 121 * here provide support for adding and subtracting timeval structures 122 * and decrementing interval timers, optionally reloading the interval 123 * timers when they expire. 124 */ 125 126 /* This function is used by clock_settime and settimeofday */ 127 static int 128 settime1(struct proc *p, struct timespec *ts, bool check_kauth) 129 { 130 struct timeval delta, tv; 131 struct timeval now; 132 struct timespec ts1; 133 struct bintime btdelta; 134 lwp_t *l; 135 int s; 136 137 TIMESPEC_TO_TIMEVAL(&tv, ts); 138 139 /* WHAT DO WE DO ABOUT PENDING REAL-TIME TIMEOUTS??? */ 140 s = splclock(); 141 microtime(&now); 142 timersub(&tv, &now, &delta); 143 144 if (check_kauth && kauth_authorize_system(kauth_cred_get(), 145 KAUTH_SYSTEM_TIME, KAUTH_REQ_SYSTEM_TIME_SYSTEM, ts, &delta, 146 KAUTH_ARG(check_kauth ? false : true)) != 0) { 147 splx(s); 148 return (EPERM); 149 } 150 151 #ifdef notyet 152 if ((delta.tv_sec < 86400) && securelevel > 0) { /* XXX elad - notyet */ 153 splx(s); 154 return (EPERM); 155 } 156 #endif 157 158 TIMEVAL_TO_TIMESPEC(&tv, &ts1); 159 tc_setclock(&ts1); 160 161 timeradd(&boottime, &delta, &boottime); 162 163 /* 164 * XXXSMP: There is a short race between setting the time above 165 * and adjusting LWP's run times. Fixing this properly means 166 * pausing all CPUs while we adjust the clock. 167 */ 168 timeval2bintime(&delta, &btdelta); 169 mutex_enter(proc_lock); 170 LIST_FOREACH(l, &alllwp, l_list) { 171 lwp_lock(l); 172 bintime_add(&l->l_stime, &btdelta); 173 lwp_unlock(l); 174 } 175 mutex_exit(proc_lock); 176 resettodr(); 177 splx(s); 178 179 return (0); 180 } 181 182 int 183 settime(struct proc *p, struct timespec *ts) 184 { 185 return (settime1(p, ts, true)); 186 } 187 188 /* ARGSUSED */ 189 int 190 sys_clock_gettime(struct lwp *l, const struct sys_clock_gettime_args *uap, 191 register_t *retval) 192 { 193 /* { 194 syscallarg(clockid_t) clock_id; 195 syscallarg(struct timespec *) tp; 196 } */ 197 clockid_t clock_id; 198 struct timespec ats; 199 200 clock_id = SCARG(uap, clock_id); 201 switch (clock_id) { 202 case CLOCK_REALTIME: 203 nanotime(&ats); 204 break; 205 case CLOCK_MONOTONIC: 206 nanouptime(&ats); 207 break; 208 default: 209 return (EINVAL); 210 } 211 212 return copyout(&ats, SCARG(uap, tp), sizeof(ats)); 213 } 214 215 /* ARGSUSED */ 216 int 217 sys_clock_settime(struct lwp *l, const struct sys_clock_settime_args *uap, 218 register_t *retval) 219 { 220 /* { 221 syscallarg(clockid_t) clock_id; 222 syscallarg(const struct timespec *) tp; 223 } */ 224 225 return clock_settime1(l->l_proc, SCARG(uap, clock_id), SCARG(uap, tp), 226 true); 227 } 228 229 230 int 231 clock_settime1(struct proc *p, clockid_t clock_id, const struct timespec *tp, 232 bool check_kauth) 233 { 234 struct timespec ats; 235 int error; 236 237 if ((error = copyin(tp, &ats, sizeof(ats))) != 0) 238 return (error); 239 240 switch (clock_id) { 241 case CLOCK_REALTIME: 242 if ((error = settime1(p, &ats, check_kauth)) != 0) 243 return (error); 244 break; 245 case CLOCK_MONOTONIC: 246 return (EINVAL); /* read-only clock */ 247 default: 248 return (EINVAL); 249 } 250 251 return 0; 252 } 253 254 int 255 sys_clock_getres(struct lwp *l, const struct sys_clock_getres_args *uap, 256 register_t *retval) 257 { 258 /* { 259 syscallarg(clockid_t) clock_id; 260 syscallarg(struct timespec *) tp; 261 } */ 262 clockid_t clock_id; 263 struct timespec ts; 264 int error = 0; 265 266 clock_id = SCARG(uap, clock_id); 267 switch (clock_id) { 268 case CLOCK_REALTIME: 269 case CLOCK_MONOTONIC: 270 ts.tv_sec = 0; 271 if (tc_getfrequency() > 1000000000) 272 ts.tv_nsec = 1; 273 else 274 ts.tv_nsec = 1000000000 / tc_getfrequency(); 275 break; 276 default: 277 return (EINVAL); 278 } 279 280 if (SCARG(uap, tp)) 281 error = copyout(&ts, SCARG(uap, tp), sizeof(ts)); 282 283 return error; 284 } 285 286 /* ARGSUSED */ 287 int 288 sys_nanosleep(struct lwp *l, const struct sys_nanosleep_args *uap, 289 register_t *retval) 290 { 291 /* { 292 syscallarg(struct timespec *) rqtp; 293 syscallarg(struct timespec *) rmtp; 294 } */ 295 struct timespec rmt, rqt; 296 int error, error1; 297 298 error = copyin(SCARG(uap, rqtp), &rqt, sizeof(struct timespec)); 299 if (error) 300 return (error); 301 302 error = nanosleep1(l, &rqt, SCARG(uap, rmtp) ? &rmt : NULL); 303 if (SCARG(uap, rmtp) == NULL || (error != 0 && error != EINTR)) 304 return error; 305 306 error1 = copyout(&rmt, SCARG(uap, rmtp), sizeof(rmt)); 307 return error1 ? error1 : error; 308 } 309 310 int 311 nanosleep1(struct lwp *l, struct timespec *rqt, struct timespec *rmt) 312 { 313 struct timespec rmtstart; 314 int error, timo; 315 316 if (itimespecfix(rqt)) 317 return (EINVAL); 318 319 timo = tstohz(rqt); 320 /* 321 * Avoid inadvertantly sleeping forever 322 */ 323 if (timo == 0) 324 timo = 1; 325 getnanouptime(&rmtstart); 326 again: 327 error = kpause("nanoslp", true, timo, NULL); 328 if (rmt != NULL || error == 0) { 329 struct timespec rmtend; 330 struct timespec t0; 331 struct timespec *t; 332 333 getnanouptime(&rmtend); 334 t = (rmt != NULL) ? rmt : &t0; 335 timespecsub(&rmtend, &rmtstart, t); 336 timespecsub(rqt, t, t); 337 if (t->tv_sec < 0) 338 timespecclear(t); 339 if (error == 0) { 340 timo = tstohz(t); 341 if (timo > 0) 342 goto again; 343 } 344 } 345 346 if (error == ERESTART) 347 error = EINTR; 348 if (error == EWOULDBLOCK) 349 error = 0; 350 351 return error; 352 } 353 354 /* ARGSUSED */ 355 int 356 sys_gettimeofday(struct lwp *l, const struct sys_gettimeofday_args *uap, 357 register_t *retval) 358 { 359 /* { 360 syscallarg(struct timeval *) tp; 361 syscallarg(void *) tzp; really "struct timezone *"; 362 } */ 363 struct timeval atv; 364 int error = 0; 365 struct timezone tzfake; 366 367 if (SCARG(uap, tp)) { 368 microtime(&atv); 369 error = copyout(&atv, SCARG(uap, tp), sizeof(atv)); 370 if (error) 371 return (error); 372 } 373 if (SCARG(uap, tzp)) { 374 /* 375 * NetBSD has no kernel notion of time zone, so we just 376 * fake up a timezone struct and return it if demanded. 377 */ 378 tzfake.tz_minuteswest = 0; 379 tzfake.tz_dsttime = 0; 380 error = copyout(&tzfake, SCARG(uap, tzp), sizeof(tzfake)); 381 } 382 return (error); 383 } 384 385 /* ARGSUSED */ 386 int 387 sys_settimeofday(struct lwp *l, const struct sys_settimeofday_args *uap, 388 register_t *retval) 389 { 390 /* { 391 syscallarg(const struct timeval *) tv; 392 syscallarg(const void *) tzp; really "const struct timezone *"; 393 } */ 394 395 return settimeofday1(SCARG(uap, tv), true, SCARG(uap, tzp), l, true); 396 } 397 398 int 399 settimeofday1(const struct timeval *utv, bool userspace, 400 const void *utzp, struct lwp *l, bool check_kauth) 401 { 402 struct timeval atv; 403 struct timespec ts; 404 int error; 405 406 /* Verify all parameters before changing time. */ 407 408 /* 409 * NetBSD has no kernel notion of time zone, and only an 410 * obsolete program would try to set it, so we log a warning. 411 */ 412 if (utzp) 413 log(LOG_WARNING, "pid %d attempted to set the " 414 "(obsolete) kernel time zone\n", l->l_proc->p_pid); 415 416 if (utv == NULL) 417 return 0; 418 419 if (userspace) { 420 if ((error = copyin(utv, &atv, sizeof(atv))) != 0) 421 return error; 422 utv = &atv; 423 } 424 425 TIMEVAL_TO_TIMESPEC(utv, &ts); 426 return settime1(l->l_proc, &ts, check_kauth); 427 } 428 429 int time_adjusted; /* set if an adjustment is made */ 430 431 /* ARGSUSED */ 432 int 433 sys_adjtime(struct lwp *l, const struct sys_adjtime_args *uap, 434 register_t *retval) 435 { 436 /* { 437 syscallarg(const struct timeval *) delta; 438 syscallarg(struct timeval *) olddelta; 439 } */ 440 int error; 441 442 if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_TIME, 443 KAUTH_REQ_SYSTEM_TIME_ADJTIME, NULL, NULL, NULL)) != 0) 444 return (error); 445 446 return adjtime1(SCARG(uap, delta), SCARG(uap, olddelta), l->l_proc); 447 } 448 449 int 450 adjtime1(const struct timeval *delta, struct timeval *olddelta, struct proc *p) 451 { 452 struct timeval atv; 453 int error = 0; 454 455 extern int64_t time_adjtime; /* in kern_ntptime.c */ 456 457 if (olddelta) { 458 mutex_spin_enter(&timecounter_lock); 459 atv.tv_sec = time_adjtime / 1000000; 460 atv.tv_usec = time_adjtime % 1000000; 461 mutex_spin_exit(&timecounter_lock); 462 if (atv.tv_usec < 0) { 463 atv.tv_usec += 1000000; 464 atv.tv_sec--; 465 } 466 error = copyout(&atv, olddelta, sizeof(struct timeval)); 467 if (error) 468 return (error); 469 } 470 471 if (delta) { 472 error = copyin(delta, &atv, sizeof(struct timeval)); 473 if (error) 474 return (error); 475 476 mutex_spin_enter(&timecounter_lock); 477 time_adjtime = (int64_t)atv.tv_sec * 1000000 + 478 atv.tv_usec; 479 if (time_adjtime) { 480 /* We need to save the system time during shutdown */ 481 time_adjusted |= 1; 482 } 483 mutex_spin_exit(&timecounter_lock); 484 } 485 486 return error; 487 } 488 489 /* 490 * Interval timer support. Both the BSD getitimer() family and the POSIX 491 * timer_*() family of routines are supported. 492 * 493 * All timers are kept in an array pointed to by p_timers, which is 494 * allocated on demand - many processes don't use timers at all. The 495 * first three elements in this array are reserved for the BSD timers: 496 * element 0 is ITIMER_REAL, element 1 is ITIMER_VIRTUAL, and element 497 * 2 is ITIMER_PROF. The rest may be allocated by the timer_create() 498 * syscall. 499 * 500 * Realtime timers are kept in the ptimer structure as an absolute 501 * time; virtual time timers are kept as a linked list of deltas. 502 * Virtual time timers are processed in the hardclock() routine of 503 * kern_clock.c. The real time timer is processed by a callout 504 * routine, called from the softclock() routine. Since a callout may 505 * be delayed in real time due to interrupt processing in the system, 506 * it is possible for the real time timeout routine (realtimeexpire, 507 * given below), to be delayed in real time past when it is supposed 508 * to occur. It does not suffice, therefore, to reload the real timer 509 * .it_value from the real time timers .it_interval. Rather, we 510 * compute the next time in absolute time the timer should go off. */ 511 512 /* Allocate a POSIX realtime timer. */ 513 int 514 sys_timer_create(struct lwp *l, const struct sys_timer_create_args *uap, 515 register_t *retval) 516 { 517 /* { 518 syscallarg(clockid_t) clock_id; 519 syscallarg(struct sigevent *) evp; 520 syscallarg(timer_t *) timerid; 521 } */ 522 523 return timer_create1(SCARG(uap, timerid), SCARG(uap, clock_id), 524 SCARG(uap, evp), copyin, l); 525 } 526 527 int 528 timer_create1(timer_t *tid, clockid_t id, struct sigevent *evp, 529 copyin_t fetch_event, struct lwp *l) 530 { 531 int error; 532 timer_t timerid; 533 struct ptimers *pts; 534 struct ptimer *pt; 535 struct proc *p; 536 537 p = l->l_proc; 538 539 if (id < CLOCK_REALTIME || id > CLOCK_PROF) 540 return (EINVAL); 541 542 if ((pts = p->p_timers) == NULL) 543 pts = timers_alloc(p); 544 545 pt = pool_get(&ptimer_pool, PR_WAITOK); 546 if (evp != NULL) { 547 if (((error = 548 (*fetch_event)(evp, &pt->pt_ev, sizeof(pt->pt_ev))) != 0) || 549 ((pt->pt_ev.sigev_notify < SIGEV_NONE) || 550 (pt->pt_ev.sigev_notify > SIGEV_SA))) { 551 pool_put(&ptimer_pool, pt); 552 return (error ? error : EINVAL); 553 } 554 } 555 556 /* Find a free timer slot, skipping those reserved for setitimer(). */ 557 mutex_spin_enter(&timer_lock); 558 for (timerid = 3; timerid < TIMER_MAX; timerid++) 559 if (pts->pts_timers[timerid] == NULL) 560 break; 561 if (timerid == TIMER_MAX) { 562 mutex_spin_exit(&timer_lock); 563 pool_put(&ptimer_pool, pt); 564 return EAGAIN; 565 } 566 if (evp == NULL) { 567 pt->pt_ev.sigev_notify = SIGEV_SIGNAL; 568 switch (id) { 569 case CLOCK_REALTIME: 570 pt->pt_ev.sigev_signo = SIGALRM; 571 break; 572 case CLOCK_VIRTUAL: 573 pt->pt_ev.sigev_signo = SIGVTALRM; 574 break; 575 case CLOCK_PROF: 576 pt->pt_ev.sigev_signo = SIGPROF; 577 break; 578 } 579 pt->pt_ev.sigev_value.sival_int = timerid; 580 } 581 pt->pt_info.ksi_signo = pt->pt_ev.sigev_signo; 582 pt->pt_info.ksi_errno = 0; 583 pt->pt_info.ksi_code = 0; 584 pt->pt_info.ksi_pid = p->p_pid; 585 pt->pt_info.ksi_uid = kauth_cred_getuid(l->l_cred); 586 pt->pt_info.ksi_value = pt->pt_ev.sigev_value; 587 pt->pt_type = id; 588 pt->pt_proc = p; 589 pt->pt_overruns = 0; 590 pt->pt_poverruns = 0; 591 pt->pt_entry = timerid; 592 pt->pt_queued = false; 593 pt->pt_active = 0; 594 timerclear(&pt->pt_time.it_value); 595 callout_init(&pt->pt_ch, 0); 596 pts->pts_timers[timerid] = pt; 597 mutex_spin_exit(&timer_lock); 598 599 return copyout(&timerid, tid, sizeof(timerid)); 600 } 601 602 /* Delete a POSIX realtime timer */ 603 int 604 sys_timer_delete(struct lwp *l, const struct sys_timer_delete_args *uap, 605 register_t *retval) 606 { 607 /* { 608 syscallarg(timer_t) timerid; 609 } */ 610 struct proc *p = l->l_proc; 611 timer_t timerid; 612 struct ptimers *pts; 613 struct ptimer *pt, *ptn; 614 615 timerid = SCARG(uap, timerid); 616 pts = p->p_timers; 617 618 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 619 return (EINVAL); 620 621 mutex_spin_enter(&timer_lock); 622 if ((pt = pts->pts_timers[timerid]) == NULL) { 623 mutex_spin_exit(&timer_lock); 624 return (EINVAL); 625 } 626 if (pt->pt_active) { 627 ptn = LIST_NEXT(pt, pt_list); 628 LIST_REMOVE(pt, pt_list); 629 for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list)) 630 timeradd(&pt->pt_time.it_value, &ptn->pt_time.it_value, 631 &ptn->pt_time.it_value); 632 pt->pt_active = 0; 633 } 634 itimerfree(pts, timerid); 635 636 return (0); 637 } 638 639 /* 640 * Set up the given timer. The value in pt->pt_time.it_value is taken 641 * to be an absolute time for CLOCK_REALTIME timers and a relative 642 * time for virtual timers. 643 * Must be called at splclock(). 644 */ 645 void 646 timer_settime(struct ptimer *pt) 647 { 648 struct ptimer *ptn, *pptn; 649 struct ptlist *ptl; 650 651 KASSERT(mutex_owned(&timer_lock)); 652 653 if (pt->pt_type == CLOCK_REALTIME) { 654 callout_stop(&pt->pt_ch); 655 if (timerisset(&pt->pt_time.it_value)) { 656 /* 657 * Don't need to check hzto() return value, here. 658 * callout_reset() does it for us. 659 */ 660 callout_reset(&pt->pt_ch, hzto(&pt->pt_time.it_value), 661 realtimerexpire, pt); 662 } 663 } else { 664 if (pt->pt_active) { 665 ptn = LIST_NEXT(pt, pt_list); 666 LIST_REMOVE(pt, pt_list); 667 for ( ; ptn; ptn = LIST_NEXT(ptn, pt_list)) 668 timeradd(&pt->pt_time.it_value, 669 &ptn->pt_time.it_value, 670 &ptn->pt_time.it_value); 671 } 672 if (timerisset(&pt->pt_time.it_value)) { 673 if (pt->pt_type == CLOCK_VIRTUAL) 674 ptl = &pt->pt_proc->p_timers->pts_virtual; 675 else 676 ptl = &pt->pt_proc->p_timers->pts_prof; 677 678 for (ptn = LIST_FIRST(ptl), pptn = NULL; 679 ptn && timercmp(&pt->pt_time.it_value, 680 &ptn->pt_time.it_value, >); 681 pptn = ptn, ptn = LIST_NEXT(ptn, pt_list)) 682 timersub(&pt->pt_time.it_value, 683 &ptn->pt_time.it_value, 684 &pt->pt_time.it_value); 685 686 if (pptn) 687 LIST_INSERT_AFTER(pptn, pt, pt_list); 688 else 689 LIST_INSERT_HEAD(ptl, pt, pt_list); 690 691 for ( ; ptn ; ptn = LIST_NEXT(ptn, pt_list)) 692 timersub(&ptn->pt_time.it_value, 693 &pt->pt_time.it_value, 694 &ptn->pt_time.it_value); 695 696 pt->pt_active = 1; 697 } else 698 pt->pt_active = 0; 699 } 700 } 701 702 void 703 timer_gettime(struct ptimer *pt, struct itimerval *aitv) 704 { 705 struct timeval now; 706 struct ptimer *ptn; 707 708 KASSERT(mutex_owned(&timer_lock)); 709 710 *aitv = pt->pt_time; 711 if (pt->pt_type == CLOCK_REALTIME) { 712 /* 713 * Convert from absolute to relative time in .it_value 714 * part of real time timer. If time for real time 715 * timer has passed return 0, else return difference 716 * between current time and time for the timer to go 717 * off. 718 */ 719 if (timerisset(&aitv->it_value)) { 720 getmicrotime(&now); 721 if (timercmp(&aitv->it_value, &now, <)) 722 timerclear(&aitv->it_value); 723 else 724 timersub(&aitv->it_value, &now, 725 &aitv->it_value); 726 } 727 } else if (pt->pt_active) { 728 if (pt->pt_type == CLOCK_VIRTUAL) 729 ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_virtual); 730 else 731 ptn = LIST_FIRST(&pt->pt_proc->p_timers->pts_prof); 732 for ( ; ptn && ptn != pt; ptn = LIST_NEXT(ptn, pt_list)) 733 timeradd(&aitv->it_value, 734 &ptn->pt_time.it_value, &aitv->it_value); 735 KASSERT(ptn != NULL); /* pt should be findable on the list */ 736 } else 737 timerclear(&aitv->it_value); 738 } 739 740 741 742 /* Set and arm a POSIX realtime timer */ 743 int 744 sys_timer_settime(struct lwp *l, const struct sys_timer_settime_args *uap, 745 register_t *retval) 746 { 747 /* { 748 syscallarg(timer_t) timerid; 749 syscallarg(int) flags; 750 syscallarg(const struct itimerspec *) value; 751 syscallarg(struct itimerspec *) ovalue; 752 } */ 753 int error; 754 struct itimerspec value, ovalue, *ovp = NULL; 755 756 if ((error = copyin(SCARG(uap, value), &value, 757 sizeof(struct itimerspec))) != 0) 758 return (error); 759 760 if (SCARG(uap, ovalue)) 761 ovp = &ovalue; 762 763 if ((error = dotimer_settime(SCARG(uap, timerid), &value, ovp, 764 SCARG(uap, flags), l->l_proc)) != 0) 765 return error; 766 767 if (ovp) 768 return copyout(&ovalue, SCARG(uap, ovalue), 769 sizeof(struct itimerspec)); 770 return 0; 771 } 772 773 int 774 dotimer_settime(int timerid, struct itimerspec *value, 775 struct itimerspec *ovalue, int flags, struct proc *p) 776 { 777 struct timeval now; 778 struct itimerval val, oval; 779 struct ptimers *pts; 780 struct ptimer *pt; 781 782 pts = p->p_timers; 783 784 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 785 return EINVAL; 786 TIMESPEC_TO_TIMEVAL(&val.it_value, &value->it_value); 787 TIMESPEC_TO_TIMEVAL(&val.it_interval, &value->it_interval); 788 if (itimerfix(&val.it_value) || itimerfix(&val.it_interval)) 789 return (EINVAL); 790 791 mutex_spin_enter(&timer_lock); 792 if ((pt = pts->pts_timers[timerid]) == NULL) { 793 mutex_spin_exit(&timer_lock); 794 return (EINVAL); 795 } 796 797 oval = pt->pt_time; 798 pt->pt_time = val; 799 800 /* 801 * If we've been passed a relative time for a realtime timer, 802 * convert it to absolute; if an absolute time for a virtual 803 * timer, convert it to relative and make sure we don't set it 804 * to zero, which would cancel the timer, or let it go 805 * negative, which would confuse the comparison tests. 806 */ 807 if (timerisset(&pt->pt_time.it_value)) { 808 if (pt->pt_type == CLOCK_REALTIME) { 809 if ((flags & TIMER_ABSTIME) == 0) { 810 getmicrotime(&now); 811 timeradd(&pt->pt_time.it_value, &now, 812 &pt->pt_time.it_value); 813 } 814 } else { 815 if ((flags & TIMER_ABSTIME) != 0) { 816 getmicrotime(&now); 817 timersub(&pt->pt_time.it_value, &now, 818 &pt->pt_time.it_value); 819 if (!timerisset(&pt->pt_time.it_value) || 820 pt->pt_time.it_value.tv_sec < 0) { 821 pt->pt_time.it_value.tv_sec = 0; 822 pt->pt_time.it_value.tv_usec = 1; 823 } 824 } 825 } 826 } 827 828 timer_settime(pt); 829 mutex_spin_exit(&timer_lock); 830 831 if (ovalue) { 832 TIMEVAL_TO_TIMESPEC(&oval.it_value, &ovalue->it_value); 833 TIMEVAL_TO_TIMESPEC(&oval.it_interval, &ovalue->it_interval); 834 } 835 836 return (0); 837 } 838 839 /* Return the time remaining until a POSIX timer fires. */ 840 int 841 sys_timer_gettime(struct lwp *l, const struct sys_timer_gettime_args *uap, 842 register_t *retval) 843 { 844 /* { 845 syscallarg(timer_t) timerid; 846 syscallarg(struct itimerspec *) value; 847 } */ 848 struct itimerspec its; 849 int error; 850 851 if ((error = dotimer_gettime(SCARG(uap, timerid), l->l_proc, 852 &its)) != 0) 853 return error; 854 855 return copyout(&its, SCARG(uap, value), sizeof(its)); 856 } 857 858 int 859 dotimer_gettime(int timerid, struct proc *p, struct itimerspec *its) 860 { 861 struct ptimer *pt; 862 struct ptimers *pts; 863 struct itimerval aitv; 864 865 pts = p->p_timers; 866 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 867 return (EINVAL); 868 mutex_spin_enter(&timer_lock); 869 if ((pt = pts->pts_timers[timerid]) == NULL) { 870 mutex_spin_exit(&timer_lock); 871 return (EINVAL); 872 } 873 timer_gettime(pt, &aitv); 874 mutex_spin_exit(&timer_lock); 875 876 TIMEVAL_TO_TIMESPEC(&aitv.it_interval, &its->it_interval); 877 TIMEVAL_TO_TIMESPEC(&aitv.it_value, &its->it_value); 878 879 return 0; 880 } 881 882 /* 883 * Return the count of the number of times a periodic timer expired 884 * while a notification was already pending. The counter is reset when 885 * a timer expires and a notification can be posted. 886 */ 887 int 888 sys_timer_getoverrun(struct lwp *l, const struct sys_timer_getoverrun_args *uap, 889 register_t *retval) 890 { 891 /* { 892 syscallarg(timer_t) timerid; 893 } */ 894 struct proc *p = l->l_proc; 895 struct ptimers *pts; 896 int timerid; 897 struct ptimer *pt; 898 899 timerid = SCARG(uap, timerid); 900 901 pts = p->p_timers; 902 if (pts == NULL || timerid < 2 || timerid >= TIMER_MAX) 903 return (EINVAL); 904 mutex_spin_enter(&timer_lock); 905 if ((pt = pts->pts_timers[timerid]) == NULL) { 906 mutex_spin_exit(&timer_lock); 907 return (EINVAL); 908 } 909 *retval = pt->pt_poverruns; 910 mutex_spin_exit(&timer_lock); 911 912 return (0); 913 } 914 915 /* 916 * Real interval timer expired: 917 * send process whose timer expired an alarm signal. 918 * If time is not set up to reload, then just return. 919 * Else compute next time timer should go off which is > current time. 920 * This is where delay in processing this timeout causes multiple 921 * SIGALRM calls to be compressed into one. 922 */ 923 void 924 realtimerexpire(void *arg) 925 { 926 uint64_t last_val, next_val, interval, now_ms; 927 struct timeval now, next; 928 struct ptimer *pt; 929 int backwards; 930 931 pt = arg; 932 933 mutex_spin_enter(&timer_lock); 934 itimerfire(pt); 935 936 if (!timerisset(&pt->pt_time.it_interval)) { 937 timerclear(&pt->pt_time.it_value); 938 mutex_spin_exit(&timer_lock); 939 return; 940 } 941 942 getmicrotime(&now); 943 backwards = (timercmp(&pt->pt_time.it_value, &now, >)); 944 timeradd(&pt->pt_time.it_value, &pt->pt_time.it_interval, &next); 945 /* Handle the easy case of non-overflown timers first. */ 946 if (!backwards && timercmp(&next, &now, >)) { 947 pt->pt_time.it_value = next; 948 } else { 949 #define TV2MS(x) (((uint64_t)(x)->tv_sec) * 1000000 + (x)->tv_usec) 950 now_ms = TV2MS(&now); 951 last_val = TV2MS(&pt->pt_time.it_value); 952 interval = TV2MS(&pt->pt_time.it_interval); 953 #undef TV2MS 954 955 next_val = now_ms + 956 (now_ms - last_val + interval - 1) % interval; 957 958 if (backwards) 959 next_val += interval; 960 else 961 pt->pt_overruns += (now_ms - last_val) / interval; 962 963 pt->pt_time.it_value.tv_sec = next_val / 1000000; 964 pt->pt_time.it_value.tv_usec = next_val % 1000000; 965 } 966 967 /* 968 * Don't need to check hzto() return value, here. 969 * callout_reset() does it for us. 970 */ 971 callout_reset(&pt->pt_ch, hzto(&pt->pt_time.it_value), 972 realtimerexpire, pt); 973 mutex_spin_exit(&timer_lock); 974 } 975 976 /* BSD routine to get the value of an interval timer. */ 977 /* ARGSUSED */ 978 int 979 sys_getitimer(struct lwp *l, const struct sys_getitimer_args *uap, 980 register_t *retval) 981 { 982 /* { 983 syscallarg(int) which; 984 syscallarg(struct itimerval *) itv; 985 } */ 986 struct proc *p = l->l_proc; 987 struct itimerval aitv; 988 int error; 989 990 error = dogetitimer(p, SCARG(uap, which), &aitv); 991 if (error) 992 return error; 993 return (copyout(&aitv, SCARG(uap, itv), sizeof(struct itimerval))); 994 } 995 996 int 997 dogetitimer(struct proc *p, int which, struct itimerval *itvp) 998 { 999 struct ptimers *pts; 1000 struct ptimer *pt; 1001 1002 if ((u_int)which > ITIMER_PROF) 1003 return (EINVAL); 1004 1005 mutex_spin_enter(&timer_lock); 1006 pts = p->p_timers; 1007 if (pts == NULL || (pt = pts->pts_timers[which]) == NULL) { 1008 timerclear(&itvp->it_value); 1009 timerclear(&itvp->it_interval); 1010 } else 1011 timer_gettime(pt, itvp); 1012 mutex_spin_exit(&timer_lock); 1013 1014 return 0; 1015 } 1016 1017 /* BSD routine to set/arm an interval timer. */ 1018 /* ARGSUSED */ 1019 int 1020 sys_setitimer(struct lwp *l, const struct sys_setitimer_args *uap, 1021 register_t *retval) 1022 { 1023 /* { 1024 syscallarg(int) which; 1025 syscallarg(const struct itimerval *) itv; 1026 syscallarg(struct itimerval *) oitv; 1027 } */ 1028 struct proc *p = l->l_proc; 1029 int which = SCARG(uap, which); 1030 struct sys_getitimer_args getargs; 1031 const struct itimerval *itvp; 1032 struct itimerval aitv; 1033 int error; 1034 1035 if ((u_int)which > ITIMER_PROF) 1036 return (EINVAL); 1037 itvp = SCARG(uap, itv); 1038 if (itvp && 1039 (error = copyin(itvp, &aitv, sizeof(struct itimerval)) != 0)) 1040 return (error); 1041 if (SCARG(uap, oitv) != NULL) { 1042 SCARG(&getargs, which) = which; 1043 SCARG(&getargs, itv) = SCARG(uap, oitv); 1044 if ((error = sys_getitimer(l, &getargs, retval)) != 0) 1045 return (error); 1046 } 1047 if (itvp == 0) 1048 return (0); 1049 1050 return dosetitimer(p, which, &aitv); 1051 } 1052 1053 int 1054 dosetitimer(struct proc *p, int which, struct itimerval *itvp) 1055 { 1056 struct timeval now; 1057 struct ptimers *pts; 1058 struct ptimer *pt, *spare; 1059 1060 if (itimerfix(&itvp->it_value) || itimerfix(&itvp->it_interval)) 1061 return (EINVAL); 1062 1063 /* 1064 * Don't bother allocating data structures if the process just 1065 * wants to clear the timer. 1066 */ 1067 spare = NULL; 1068 pts = p->p_timers; 1069 retry: 1070 if (!timerisset(&itvp->it_value) && (pts == NULL || 1071 pts->pts_timers[which] == NULL)) 1072 return (0); 1073 if (pts == NULL) 1074 pts = timers_alloc(p); 1075 mutex_spin_enter(&timer_lock); 1076 pt = pts->pts_timers[which]; 1077 if (pt == NULL) { 1078 if (spare == NULL) { 1079 mutex_spin_exit(&timer_lock); 1080 spare = pool_get(&ptimer_pool, PR_WAITOK); 1081 goto retry; 1082 } 1083 pt = spare; 1084 spare = NULL; 1085 pt->pt_ev.sigev_notify = SIGEV_SIGNAL; 1086 pt->pt_ev.sigev_value.sival_int = which; 1087 pt->pt_overruns = 0; 1088 pt->pt_proc = p; 1089 pt->pt_type = which; 1090 pt->pt_entry = which; 1091 pt->pt_active = 0; 1092 pt->pt_queued = false; 1093 callout_init(&pt->pt_ch, CALLOUT_MPSAFE); 1094 switch (which) { 1095 case ITIMER_REAL: 1096 pt->pt_ev.sigev_signo = SIGALRM; 1097 break; 1098 case ITIMER_VIRTUAL: 1099 pt->pt_ev.sigev_signo = SIGVTALRM; 1100 break; 1101 case ITIMER_PROF: 1102 pt->pt_ev.sigev_signo = SIGPROF; 1103 break; 1104 } 1105 pts->pts_timers[which] = pt; 1106 } 1107 pt->pt_time = *itvp; 1108 1109 if ((which == ITIMER_REAL) && timerisset(&pt->pt_time.it_value)) { 1110 /* Convert to absolute time */ 1111 /* XXX need to wrap in splclock for timecounters case? */ 1112 getmicrotime(&now); 1113 timeradd(&pt->pt_time.it_value, &now, &pt->pt_time.it_value); 1114 } 1115 timer_settime(pt); 1116 mutex_spin_exit(&timer_lock); 1117 if (spare != NULL) 1118 pool_put(&ptimer_pool, spare); 1119 1120 return (0); 1121 } 1122 1123 /* Utility routines to manage the array of pointers to timers. */ 1124 struct ptimers * 1125 timers_alloc(struct proc *p) 1126 { 1127 struct ptimers *pts; 1128 int i; 1129 1130 pts = pool_get(&ptimers_pool, PR_WAITOK); 1131 LIST_INIT(&pts->pts_virtual); 1132 LIST_INIT(&pts->pts_prof); 1133 for (i = 0; i < TIMER_MAX; i++) 1134 pts->pts_timers[i] = NULL; 1135 pts->pts_fired = 0; 1136 mutex_spin_enter(&timer_lock); 1137 if (p->p_timers == NULL) { 1138 p->p_timers = pts; 1139 mutex_spin_exit(&timer_lock); 1140 return pts; 1141 } 1142 mutex_spin_exit(&timer_lock); 1143 pool_put(&ptimers_pool, pts); 1144 return p->p_timers; 1145 } 1146 1147 /* 1148 * Clean up the per-process timers. If "which" is set to TIMERS_ALL, 1149 * then clean up all timers and free all the data structures. If 1150 * "which" is set to TIMERS_POSIX, only clean up the timers allocated 1151 * by timer_create(), not the BSD setitimer() timers, and only free the 1152 * structure if none of those remain. 1153 */ 1154 void 1155 timers_free(struct proc *p, int which) 1156 { 1157 struct ptimers *pts; 1158 struct ptimer *ptn; 1159 struct timeval tv; 1160 int i; 1161 1162 if (p->p_timers == NULL) 1163 return; 1164 1165 pts = p->p_timers; 1166 mutex_spin_enter(&timer_lock); 1167 if (which == TIMERS_ALL) { 1168 p->p_timers = NULL; 1169 i = 0; 1170 } else { 1171 timerclear(&tv); 1172 for (ptn = LIST_FIRST(&pts->pts_virtual); 1173 ptn && ptn != pts->pts_timers[ITIMER_VIRTUAL]; 1174 ptn = LIST_NEXT(ptn, pt_list)) 1175 timeradd(&tv, &ptn->pt_time.it_value, &tv); 1176 LIST_FIRST(&pts->pts_virtual) = NULL; 1177 if (ptn) { 1178 timeradd(&tv, &ptn->pt_time.it_value, 1179 &ptn->pt_time.it_value); 1180 LIST_INSERT_HEAD(&pts->pts_virtual, ptn, pt_list); 1181 } 1182 timerclear(&tv); 1183 for (ptn = LIST_FIRST(&pts->pts_prof); 1184 ptn && ptn != pts->pts_timers[ITIMER_PROF]; 1185 ptn = LIST_NEXT(ptn, pt_list)) 1186 timeradd(&tv, &ptn->pt_time.it_value, &tv); 1187 LIST_FIRST(&pts->pts_prof) = NULL; 1188 if (ptn) { 1189 timeradd(&tv, &ptn->pt_time.it_value, 1190 &ptn->pt_time.it_value); 1191 LIST_INSERT_HEAD(&pts->pts_prof, ptn, pt_list); 1192 } 1193 i = 3; 1194 } 1195 for ( ; i < TIMER_MAX; i++) { 1196 if (pts->pts_timers[i] != NULL) { 1197 itimerfree(pts, i); 1198 mutex_spin_enter(&timer_lock); 1199 } 1200 } 1201 if (pts->pts_timers[0] == NULL && pts->pts_timers[1] == NULL && 1202 pts->pts_timers[2] == NULL) { 1203 p->p_timers = NULL; 1204 mutex_spin_exit(&timer_lock); 1205 pool_put(&ptimers_pool, pts); 1206 } else 1207 mutex_spin_exit(&timer_lock); 1208 } 1209 1210 static void 1211 itimerfree(struct ptimers *pts, int index) 1212 { 1213 struct ptimer *pt; 1214 1215 KASSERT(mutex_owned(&timer_lock)); 1216 1217 pt = pts->pts_timers[index]; 1218 pts->pts_timers[index] = NULL; 1219 if (pt->pt_type == CLOCK_REALTIME) 1220 callout_halt(&pt->pt_ch, &timer_lock); 1221 else if (pt->pt_queued) 1222 TAILQ_REMOVE(&timer_queue, pt, pt_chain); 1223 mutex_spin_exit(&timer_lock); 1224 callout_destroy(&pt->pt_ch); 1225 pool_put(&ptimer_pool, pt); 1226 } 1227 1228 /* 1229 * Decrement an interval timer by a specified number 1230 * of microseconds, which must be less than a second, 1231 * i.e. < 1000000. If the timer expires, then reload 1232 * it. In this case, carry over (usec - old value) to 1233 * reduce the value reloaded into the timer so that 1234 * the timer does not drift. This routine assumes 1235 * that it is called in a context where the timers 1236 * on which it is operating cannot change in value. 1237 */ 1238 static int 1239 itimerdecr(struct ptimer *pt, int usec) 1240 { 1241 struct itimerval *itp; 1242 1243 KASSERT(mutex_owned(&timer_lock)); 1244 1245 itp = &pt->pt_time; 1246 if (itp->it_value.tv_usec < usec) { 1247 if (itp->it_value.tv_sec == 0) { 1248 /* expired, and already in next interval */ 1249 usec -= itp->it_value.tv_usec; 1250 goto expire; 1251 } 1252 itp->it_value.tv_usec += 1000000; 1253 itp->it_value.tv_sec--; 1254 } 1255 itp->it_value.tv_usec -= usec; 1256 usec = 0; 1257 if (timerisset(&itp->it_value)) 1258 return (1); 1259 /* expired, exactly at end of interval */ 1260 expire: 1261 if (timerisset(&itp->it_interval)) { 1262 itp->it_value = itp->it_interval; 1263 itp->it_value.tv_usec -= usec; 1264 if (itp->it_value.tv_usec < 0) { 1265 itp->it_value.tv_usec += 1000000; 1266 itp->it_value.tv_sec--; 1267 } 1268 timer_settime(pt); 1269 } else 1270 itp->it_value.tv_usec = 0; /* sec is already 0 */ 1271 return (0); 1272 } 1273 1274 static void 1275 itimerfire(struct ptimer *pt) 1276 { 1277 1278 KASSERT(mutex_owned(&timer_lock)); 1279 1280 /* 1281 * XXX Can overrun, but we don't do signal queueing yet, anyway. 1282 * XXX Relying on the clock interrupt is stupid. 1283 */ 1284 if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL || pt->pt_queued) 1285 return; 1286 TAILQ_INSERT_TAIL(&timer_queue, pt, pt_chain); 1287 pt->pt_queued = true; 1288 softint_schedule(timer_sih); 1289 } 1290 1291 void 1292 timer_tick(lwp_t *l, bool user) 1293 { 1294 struct ptimers *pts; 1295 struct ptimer *pt; 1296 proc_t *p; 1297 1298 p = l->l_proc; 1299 if (p->p_timers == NULL) 1300 return; 1301 1302 mutex_spin_enter(&timer_lock); 1303 if ((pts = l->l_proc->p_timers) != NULL) { 1304 /* 1305 * Run current process's virtual and profile time, as needed. 1306 */ 1307 if (user && (pt = LIST_FIRST(&pts->pts_virtual)) != NULL) 1308 if (itimerdecr(pt, tick) == 0) 1309 itimerfire(pt); 1310 if ((pt = LIST_FIRST(&pts->pts_prof)) != NULL) 1311 if (itimerdecr(pt, tick) == 0) 1312 itimerfire(pt); 1313 } 1314 mutex_spin_exit(&timer_lock); 1315 } 1316 1317 static void 1318 timer_intr(void *cookie) 1319 { 1320 ksiginfo_t ksi; 1321 struct ptimer *pt; 1322 proc_t *p; 1323 1324 mutex_spin_enter(&timer_lock); 1325 while ((pt = TAILQ_FIRST(&timer_queue)) != NULL) { 1326 TAILQ_REMOVE(&timer_queue, pt, pt_chain); 1327 KASSERT(pt->pt_queued); 1328 pt->pt_queued = false; 1329 1330 if (pt->pt_ev.sigev_notify != SIGEV_SIGNAL) 1331 continue; 1332 p = pt->pt_proc; 1333 if (pt->pt_proc->p_timers == NULL) { 1334 /* Process is dying. */ 1335 continue; 1336 } 1337 if (sigismember(&p->p_sigpend.sp_set, pt->pt_ev.sigev_signo)) { 1338 pt->pt_overruns++; 1339 continue; 1340 } 1341 1342 KSI_INIT(&ksi); 1343 ksi.ksi_signo = pt->pt_ev.sigev_signo; 1344 ksi.ksi_code = SI_TIMER; 1345 ksi.ksi_value = pt->pt_ev.sigev_value; 1346 pt->pt_poverruns = pt->pt_overruns; 1347 pt->pt_overruns = 0; 1348 mutex_spin_exit(&timer_lock); 1349 1350 mutex_enter(proc_lock); 1351 kpsignal(p, &ksi, NULL); 1352 mutex_exit(proc_lock); 1353 1354 mutex_spin_enter(&timer_lock); 1355 } 1356 mutex_spin_exit(&timer_lock); 1357 } 1358 1359 /* 1360 * ratecheck(): simple time-based rate-limit checking. see ratecheck(9) 1361 * for usage and rationale. 1362 */ 1363 int 1364 ratecheck(struct timeval *lasttime, const struct timeval *mininterval) 1365 { 1366 struct timeval tv, delta; 1367 int rv = 0; 1368 1369 getmicrouptime(&tv); 1370 timersub(&tv, lasttime, &delta); 1371 1372 /* 1373 * check for 0,0 is so that the message will be seen at least once, 1374 * even if interval is huge. 1375 */ 1376 if (timercmp(&delta, mininterval, >=) || 1377 (lasttime->tv_sec == 0 && lasttime->tv_usec == 0)) { 1378 *lasttime = tv; 1379 rv = 1; 1380 } 1381 1382 return (rv); 1383 } 1384 1385 /* 1386 * ppsratecheck(): packets (or events) per second limitation. 1387 */ 1388 int 1389 ppsratecheck(struct timeval *lasttime, int *curpps, int maxpps) 1390 { 1391 struct timeval tv, delta; 1392 int rv; 1393 1394 getmicrouptime(&tv); 1395 timersub(&tv, lasttime, &delta); 1396 1397 /* 1398 * check for 0,0 is so that the message will be seen at least once. 1399 * if more than one second have passed since the last update of 1400 * lasttime, reset the counter. 1401 * 1402 * we do increment *curpps even in *curpps < maxpps case, as some may 1403 * try to use *curpps for stat purposes as well. 1404 */ 1405 if ((lasttime->tv_sec == 0 && lasttime->tv_usec == 0) || 1406 delta.tv_sec >= 1) { 1407 *lasttime = tv; 1408 *curpps = 0; 1409 } 1410 if (maxpps < 0) 1411 rv = 1; 1412 else if (*curpps < maxpps) 1413 rv = 1; 1414 else 1415 rv = 0; 1416 1417 #if 1 /*DIAGNOSTIC?*/ 1418 /* be careful about wrap-around */ 1419 if (*curpps + 1 > *curpps) 1420 *curpps = *curpps + 1; 1421 #else 1422 /* 1423 * assume that there's not too many calls to this function. 1424 * not sure if the assumption holds, as it depends on *caller's* 1425 * behavior, not the behavior of this function. 1426 * IMHO it is wrong to make assumption on the caller's behavior, 1427 * so the above #if is #if 1, not #ifdef DIAGNOSTIC. 1428 */ 1429 *curpps = *curpps + 1; 1430 #endif 1431 1432 return (rv); 1433 } 1434