kern_time.c revision 225617
1/*- 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 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 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. 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 15 * without specific prior written permission. 16 * 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 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 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 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)kern_time.c 8.1 (Berkeley) 6/10/93 30 */ 31 32#include <sys/cdefs.h> 33__FBSDID("$FreeBSD: head/sys/kern/kern_time.c 225617 2011-09-16 13:58:51Z kmacy $"); 34 35#include <sys/param.h> 36#include <sys/systm.h> 37#include <sys/limits.h> 38#include <sys/clock.h> 39#include <sys/lock.h> 40#include <sys/mutex.h> 41#include <sys/sysproto.h> 42#include <sys/eventhandler.h> 43#include <sys/resourcevar.h> 44#include <sys/signalvar.h> 45#include <sys/kernel.h> 46#include <sys/syscallsubr.h> 47#include <sys/sysctl.h> 48#include <sys/sysent.h> 49#include <sys/priv.h> 50#include <sys/proc.h> 51#include <sys/posix4.h> 52#include <sys/time.h> 53#include <sys/timers.h> 54#include <sys/timetc.h> 55#include <sys/vnode.h> 56 57#include <vm/vm.h> 58#include <vm/vm_extern.h> 59 60#define MAX_CLOCKS (CLOCK_MONOTONIC+1) 61 62static struct kclock posix_clocks[MAX_CLOCKS]; 63static uma_zone_t itimer_zone = NULL; 64 65/* 66 * Time of day and interval timer support. 67 * 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. 73 */ 74 75static int settime(struct thread *, struct timeval *); 76static void timevalfix(struct timeval *); 77 78static void itimer_start(void); 79static int itimer_init(void *, int, int); 80static void itimer_fini(void *, int); 81static void itimer_enter(struct itimer *); 82static void itimer_leave(struct itimer *); 83static struct itimer *itimer_find(struct proc *, int); 84static void itimers_alloc(struct proc *); 85static void itimers_event_hook_exec(void *arg, struct proc *p, struct image_params *imgp); 86static void itimers_event_hook_exit(void *arg, struct proc *p); 87static int realtimer_create(struct itimer *); 88static int realtimer_gettime(struct itimer *, struct itimerspec *); 89static int realtimer_settime(struct itimer *, int, 90 struct itimerspec *, struct itimerspec *); 91static int realtimer_delete(struct itimer *); 92static void realtimer_clocktime(clockid_t, struct timespec *); 93static void realtimer_expire(void *); 94static int kern_timer_create(struct thread *, clockid_t, 95 struct sigevent *, int *, int); 96static int kern_timer_delete(struct thread *, int); 97 98int register_posix_clock(int, struct kclock *); 99void itimer_fire(struct itimer *it); 100int itimespecfix(struct timespec *ts); 101 102#define CLOCK_CALL(clock, call, arglist) \ 103 ((*posix_clocks[clock].call) arglist) 104 105SYSINIT(posix_timer, SI_SUB_P1003_1B, SI_ORDER_FIRST+4, itimer_start, NULL); 106 107 108static int 109settime(struct thread *td, struct timeval *tv) 110{ 111 struct timeval delta, tv1, tv2; 112 static struct timeval maxtime, laststep; 113 struct timespec ts; 114 int s; 115 116 s = splclock(); 117 microtime(&tv1); 118 delta = *tv; 119 timevalsub(&delta, &tv1); 120 121 /* 122 * If the system is secure, we do not allow the time to be 123 * set to a value earlier than 1 second less than the highest 124 * time we have yet seen. The worst a miscreant can do in 125 * this circumstance is "freeze" time. He couldn't go 126 * back to the past. 127 * 128 * We similarly do not allow the clock to be stepped more 129 * than one second, nor more than once per second. This allows 130 * a miscreant to make the clock march double-time, but no worse. 131 */ 132 if (securelevel_gt(td->td_ucred, 1) != 0) { 133 if (delta.tv_sec < 0 || delta.tv_usec < 0) { 134 /* 135 * Update maxtime to latest time we've seen. 136 */ 137 if (tv1.tv_sec > maxtime.tv_sec) 138 maxtime = tv1; 139 tv2 = *tv; 140 timevalsub(&tv2, &maxtime); 141 if (tv2.tv_sec < -1) { 142 tv->tv_sec = maxtime.tv_sec - 1; 143 printf("Time adjustment clamped to -1 second\n"); 144 } 145 } else { 146 if (tv1.tv_sec == laststep.tv_sec) { 147 splx(s); 148 return (EPERM); 149 } 150 if (delta.tv_sec > 1) { 151 tv->tv_sec = tv1.tv_sec + 1; 152 printf("Time adjustment clamped to +1 second\n"); 153 } 154 laststep = *tv; 155 } 156 } 157 158 ts.tv_sec = tv->tv_sec; 159 ts.tv_nsec = tv->tv_usec * 1000; 160 mtx_lock(&Giant); 161 tc_setclock(&ts); 162 resettodr(); 163 mtx_unlock(&Giant); 164 return (0); 165} 166 167#ifndef _SYS_SYSPROTO_H_ 168struct clock_gettime_args { 169 clockid_t clock_id; 170 struct timespec *tp; 171}; 172#endif 173/* ARGSUSED */ 174int 175sys_clock_gettime(struct thread *td, struct clock_gettime_args *uap) 176{ 177 struct timespec ats; 178 int error; 179 180 error = kern_clock_gettime(td, uap->clock_id, &ats); 181 if (error == 0) 182 error = copyout(&ats, uap->tp, sizeof(ats)); 183 184 return (error); 185} 186 187int 188kern_clock_gettime(struct thread *td, clockid_t clock_id, struct timespec *ats) 189{ 190 struct timeval sys, user; 191 struct proc *p; 192 uint64_t runtime, curtime, switchtime; 193 194 p = td->td_proc; 195 switch (clock_id) { 196 case CLOCK_REALTIME: /* Default to precise. */ 197 case CLOCK_REALTIME_PRECISE: 198 nanotime(ats); 199 break; 200 case CLOCK_REALTIME_FAST: 201 getnanotime(ats); 202 break; 203 case CLOCK_VIRTUAL: 204 PROC_LOCK(p); 205 PROC_SLOCK(p); 206 calcru(p, &user, &sys); 207 PROC_SUNLOCK(p); 208 PROC_UNLOCK(p); 209 TIMEVAL_TO_TIMESPEC(&user, ats); 210 break; 211 case CLOCK_PROF: 212 PROC_LOCK(p); 213 PROC_SLOCK(p); 214 calcru(p, &user, &sys); 215 PROC_SUNLOCK(p); 216 PROC_UNLOCK(p); 217 timevaladd(&user, &sys); 218 TIMEVAL_TO_TIMESPEC(&user, ats); 219 break; 220 case CLOCK_MONOTONIC: /* Default to precise. */ 221 case CLOCK_MONOTONIC_PRECISE: 222 case CLOCK_UPTIME: 223 case CLOCK_UPTIME_PRECISE: 224 nanouptime(ats); 225 break; 226 case CLOCK_UPTIME_FAST: 227 case CLOCK_MONOTONIC_FAST: 228 getnanouptime(ats); 229 break; 230 case CLOCK_SECOND: 231 ats->tv_sec = time_second; 232 ats->tv_nsec = 0; 233 break; 234 case CLOCK_THREAD_CPUTIME_ID: 235 critical_enter(); 236 switchtime = PCPU_GET(switchtime); 237 curtime = cpu_ticks(); 238 runtime = td->td_runtime; 239 critical_exit(); 240 runtime = cputick2usec(runtime + curtime - switchtime); 241 ats->tv_sec = runtime / 1000000; 242 ats->tv_nsec = runtime % 1000000 * 1000; 243 break; 244 default: 245 return (EINVAL); 246 } 247 return (0); 248} 249 250#ifndef _SYS_SYSPROTO_H_ 251struct clock_settime_args { 252 clockid_t clock_id; 253 const struct timespec *tp; 254}; 255#endif 256/* ARGSUSED */ 257int 258sys_clock_settime(struct thread *td, struct clock_settime_args *uap) 259{ 260 struct timespec ats; 261 int error; 262 263 if ((error = copyin(uap->tp, &ats, sizeof(ats))) != 0) 264 return (error); 265 return (kern_clock_settime(td, uap->clock_id, &ats)); 266} 267 268int 269kern_clock_settime(struct thread *td, clockid_t clock_id, struct timespec *ats) 270{ 271 struct timeval atv; 272 int error; 273 274 if ((error = priv_check(td, PRIV_CLOCK_SETTIME)) != 0) 275 return (error); 276 if (clock_id != CLOCK_REALTIME) 277 return (EINVAL); 278 if (ats->tv_nsec < 0 || ats->tv_nsec >= 1000000000) 279 return (EINVAL); 280 /* XXX Don't convert nsec->usec and back */ 281 TIMESPEC_TO_TIMEVAL(&atv, ats); 282 error = settime(td, &atv); 283 return (error); 284} 285 286#ifndef _SYS_SYSPROTO_H_ 287struct clock_getres_args { 288 clockid_t clock_id; 289 struct timespec *tp; 290}; 291#endif 292int 293sys_clock_getres(struct thread *td, struct clock_getres_args *uap) 294{ 295 struct timespec ts; 296 int error; 297 298 if (uap->tp == NULL) 299 return (0); 300 301 error = kern_clock_getres(td, uap->clock_id, &ts); 302 if (error == 0) 303 error = copyout(&ts, uap->tp, sizeof(ts)); 304 return (error); 305} 306 307int 308kern_clock_getres(struct thread *td, clockid_t clock_id, struct timespec *ts) 309{ 310 311 ts->tv_sec = 0; 312 switch (clock_id) { 313 case CLOCK_REALTIME: 314 case CLOCK_REALTIME_FAST: 315 case CLOCK_REALTIME_PRECISE: 316 case CLOCK_MONOTONIC: 317 case CLOCK_MONOTONIC_FAST: 318 case CLOCK_MONOTONIC_PRECISE: 319 case CLOCK_UPTIME: 320 case CLOCK_UPTIME_FAST: 321 case CLOCK_UPTIME_PRECISE: 322 /* 323 * Round up the result of the division cheaply by adding 1. 324 * Rounding up is especially important if rounding down 325 * would give 0. Perfect rounding is unimportant. 326 */ 327 ts->tv_nsec = 1000000000 / tc_getfrequency() + 1; 328 break; 329 case CLOCK_VIRTUAL: 330 case CLOCK_PROF: 331 /* Accurately round up here because we can do so cheaply. */ 332 ts->tv_nsec = (1000000000 + hz - 1) / hz; 333 break; 334 case CLOCK_SECOND: 335 ts->tv_sec = 1; 336 ts->tv_nsec = 0; 337 break; 338 case CLOCK_THREAD_CPUTIME_ID: 339 /* sync with cputick2usec */ 340 ts->tv_nsec = 1000000 / cpu_tickrate(); 341 if (ts->tv_nsec == 0) 342 ts->tv_nsec = 1000; 343 break; 344 default: 345 return (EINVAL); 346 } 347 return (0); 348} 349 350static int nanowait; 351 352int 353kern_nanosleep(struct thread *td, struct timespec *rqt, struct timespec *rmt) 354{ 355 struct timespec ts, ts2, ts3; 356 struct timeval tv; 357 int error; 358 359 if (rqt->tv_nsec < 0 || rqt->tv_nsec >= 1000000000) 360 return (EINVAL); 361 if (rqt->tv_sec < 0 || (rqt->tv_sec == 0 && rqt->tv_nsec == 0)) 362 return (0); 363 getnanouptime(&ts); 364 timespecadd(&ts, rqt); 365 TIMESPEC_TO_TIMEVAL(&tv, rqt); 366 for (;;) { 367 error = tsleep(&nanowait, PWAIT | PCATCH, "nanslp", 368 tvtohz(&tv)); 369 getnanouptime(&ts2); 370 if (error != EWOULDBLOCK) { 371 if (error == ERESTART) 372 error = EINTR; 373 if (rmt != NULL) { 374 timespecsub(&ts, &ts2); 375 if (ts.tv_sec < 0) 376 timespecclear(&ts); 377 *rmt = ts; 378 } 379 return (error); 380 } 381 if (timespeccmp(&ts2, &ts, >=)) 382 return (0); 383 ts3 = ts; 384 timespecsub(&ts3, &ts2); 385 TIMESPEC_TO_TIMEVAL(&tv, &ts3); 386 } 387} 388 389#ifndef _SYS_SYSPROTO_H_ 390struct nanosleep_args { 391 struct timespec *rqtp; 392 struct timespec *rmtp; 393}; 394#endif 395/* ARGSUSED */ 396int 397sys_nanosleep(struct thread *td, struct nanosleep_args *uap) 398{ 399 struct timespec rmt, rqt; 400 int error; 401 402 error = copyin(uap->rqtp, &rqt, sizeof(rqt)); 403 if (error) 404 return (error); 405 406 if (uap->rmtp && 407 !useracc((caddr_t)uap->rmtp, sizeof(rmt), VM_PROT_WRITE)) 408 return (EFAULT); 409 error = kern_nanosleep(td, &rqt, &rmt); 410 if (error && uap->rmtp) { 411 int error2; 412 413 error2 = copyout(&rmt, uap->rmtp, sizeof(rmt)); 414 if (error2) 415 error = error2; 416 } 417 return (error); 418} 419 420#ifndef _SYS_SYSPROTO_H_ 421struct gettimeofday_args { 422 struct timeval *tp; 423 struct timezone *tzp; 424}; 425#endif 426/* ARGSUSED */ 427int 428sys_gettimeofday(struct thread *td, struct gettimeofday_args *uap) 429{ 430 struct timeval atv; 431 struct timezone rtz; 432 int error = 0; 433 434 if (uap->tp) { 435 microtime(&atv); 436 error = copyout(&atv, uap->tp, sizeof (atv)); 437 } 438 if (error == 0 && uap->tzp != NULL) { 439 rtz.tz_minuteswest = tz_minuteswest; 440 rtz.tz_dsttime = tz_dsttime; 441 error = copyout(&rtz, uap->tzp, sizeof (rtz)); 442 } 443 return (error); 444} 445 446#ifndef _SYS_SYSPROTO_H_ 447struct settimeofday_args { 448 struct timeval *tv; 449 struct timezone *tzp; 450}; 451#endif 452/* ARGSUSED */ 453int 454sys_settimeofday(struct thread *td, struct settimeofday_args *uap) 455{ 456 struct timeval atv, *tvp; 457 struct timezone atz, *tzp; 458 int error; 459 460 if (uap->tv) { 461 error = copyin(uap->tv, &atv, sizeof(atv)); 462 if (error) 463 return (error); 464 tvp = &atv; 465 } else 466 tvp = NULL; 467 if (uap->tzp) { 468 error = copyin(uap->tzp, &atz, sizeof(atz)); 469 if (error) 470 return (error); 471 tzp = &atz; 472 } else 473 tzp = NULL; 474 return (kern_settimeofday(td, tvp, tzp)); 475} 476 477int 478kern_settimeofday(struct thread *td, struct timeval *tv, struct timezone *tzp) 479{ 480 int error; 481 482 error = priv_check(td, PRIV_SETTIMEOFDAY); 483 if (error) 484 return (error); 485 /* Verify all parameters before changing time. */ 486 if (tv) { 487 if (tv->tv_usec < 0 || tv->tv_usec >= 1000000) 488 return (EINVAL); 489 error = settime(td, tv); 490 } 491 if (tzp && error == 0) { 492 tz_minuteswest = tzp->tz_minuteswest; 493 tz_dsttime = tzp->tz_dsttime; 494 } 495 return (error); 496} 497 498/* 499 * Get value of an interval timer. The process virtual and profiling virtual 500 * time timers are kept in the p_stats area, since they can be swapped out. 501 * These are kept internally in the way they are specified externally: in 502 * time until they expire. 503 * 504 * The real time interval timer is kept in the process table slot for the 505 * process, and its value (it_value) is kept as an absolute time rather than 506 * as a delta, so that it is easy to keep periodic real-time signals from 507 * drifting. 508 * 509 * Virtual time timers are processed in the hardclock() routine of 510 * kern_clock.c. The real time timer is processed by a timeout routine, 511 * called from the softclock() routine. Since a callout may be delayed in 512 * real time due to interrupt processing in the system, it is possible for 513 * the real time timeout routine (realitexpire, given below), to be delayed 514 * in real time past when it is supposed to occur. It does not suffice, 515 * therefore, to reload the real timer .it_value from the real time timers 516 * .it_interval. Rather, we compute the next time in absolute time the timer 517 * should go off. 518 */ 519#ifndef _SYS_SYSPROTO_H_ 520struct getitimer_args { 521 u_int which; 522 struct itimerval *itv; 523}; 524#endif 525int 526sys_getitimer(struct thread *td, struct getitimer_args *uap) 527{ 528 struct itimerval aitv; 529 int error; 530 531 error = kern_getitimer(td, uap->which, &aitv); 532 if (error != 0) 533 return (error); 534 return (copyout(&aitv, uap->itv, sizeof (struct itimerval))); 535} 536 537int 538kern_getitimer(struct thread *td, u_int which, struct itimerval *aitv) 539{ 540 struct proc *p = td->td_proc; 541 struct timeval ctv; 542 543 if (which > ITIMER_PROF) 544 return (EINVAL); 545 546 if (which == ITIMER_REAL) { 547 /* 548 * Convert from absolute to relative time in .it_value 549 * part of real time timer. If time for real time timer 550 * has passed return 0, else return difference between 551 * current time and time for the timer to go off. 552 */ 553 PROC_LOCK(p); 554 *aitv = p->p_realtimer; 555 PROC_UNLOCK(p); 556 if (timevalisset(&aitv->it_value)) { 557 getmicrouptime(&ctv); 558 if (timevalcmp(&aitv->it_value, &ctv, <)) 559 timevalclear(&aitv->it_value); 560 else 561 timevalsub(&aitv->it_value, &ctv); 562 } 563 } else { 564 PROC_SLOCK(p); 565 *aitv = p->p_stats->p_timer[which]; 566 PROC_SUNLOCK(p); 567 } 568 return (0); 569} 570 571#ifndef _SYS_SYSPROTO_H_ 572struct setitimer_args { 573 u_int which; 574 struct itimerval *itv, *oitv; 575}; 576#endif 577int 578sys_setitimer(struct thread *td, struct setitimer_args *uap) 579{ 580 struct itimerval aitv, oitv; 581 int error; 582 583 if (uap->itv == NULL) { 584 uap->itv = uap->oitv; 585 return (sys_getitimer(td, (struct getitimer_args *)uap)); 586 } 587 588 if ((error = copyin(uap->itv, &aitv, sizeof(struct itimerval)))) 589 return (error); 590 error = kern_setitimer(td, uap->which, &aitv, &oitv); 591 if (error != 0 || uap->oitv == NULL) 592 return (error); 593 return (copyout(&oitv, uap->oitv, sizeof(struct itimerval))); 594} 595 596int 597kern_setitimer(struct thread *td, u_int which, struct itimerval *aitv, 598 struct itimerval *oitv) 599{ 600 struct proc *p = td->td_proc; 601 struct timeval ctv; 602 603 if (aitv == NULL) 604 return (kern_getitimer(td, which, oitv)); 605 606 if (which > ITIMER_PROF) 607 return (EINVAL); 608 if (itimerfix(&aitv->it_value)) 609 return (EINVAL); 610 if (!timevalisset(&aitv->it_value)) 611 timevalclear(&aitv->it_interval); 612 else if (itimerfix(&aitv->it_interval)) 613 return (EINVAL); 614 615 if (which == ITIMER_REAL) { 616 PROC_LOCK(p); 617 if (timevalisset(&p->p_realtimer.it_value)) 618 callout_stop(&p->p_itcallout); 619 getmicrouptime(&ctv); 620 if (timevalisset(&aitv->it_value)) { 621 callout_reset(&p->p_itcallout, tvtohz(&aitv->it_value), 622 realitexpire, p); 623 timevaladd(&aitv->it_value, &ctv); 624 } 625 *oitv = p->p_realtimer; 626 p->p_realtimer = *aitv; 627 PROC_UNLOCK(p); 628 if (timevalisset(&oitv->it_value)) { 629 if (timevalcmp(&oitv->it_value, &ctv, <)) 630 timevalclear(&oitv->it_value); 631 else 632 timevalsub(&oitv->it_value, &ctv); 633 } 634 } else { 635 PROC_SLOCK(p); 636 *oitv = p->p_stats->p_timer[which]; 637 p->p_stats->p_timer[which] = *aitv; 638 PROC_SUNLOCK(p); 639 } 640 return (0); 641} 642 643/* 644 * Real interval timer expired: 645 * send process whose timer expired an alarm signal. 646 * If time is not set up to reload, then just return. 647 * Else compute next time timer should go off which is > current time. 648 * This is where delay in processing this timeout causes multiple 649 * SIGALRM calls to be compressed into one. 650 * tvtohz() always adds 1 to allow for the time until the next clock 651 * interrupt being strictly less than 1 clock tick, but we don't want 652 * that here since we want to appear to be in sync with the clock 653 * interrupt even when we're delayed. 654 */ 655void 656realitexpire(void *arg) 657{ 658 struct proc *p; 659 struct timeval ctv, ntv; 660 661 p = (struct proc *)arg; 662 PROC_LOCK(p); 663 kern_psignal(p, SIGALRM); 664 if (!timevalisset(&p->p_realtimer.it_interval)) { 665 timevalclear(&p->p_realtimer.it_value); 666 if (p->p_flag & P_WEXIT) 667 wakeup(&p->p_itcallout); 668 PROC_UNLOCK(p); 669 return; 670 } 671 for (;;) { 672 timevaladd(&p->p_realtimer.it_value, 673 &p->p_realtimer.it_interval); 674 getmicrouptime(&ctv); 675 if (timevalcmp(&p->p_realtimer.it_value, &ctv, >)) { 676 ntv = p->p_realtimer.it_value; 677 timevalsub(&ntv, &ctv); 678 callout_reset(&p->p_itcallout, tvtohz(&ntv) - 1, 679 realitexpire, p); 680 PROC_UNLOCK(p); 681 return; 682 } 683 } 684 /*NOTREACHED*/ 685} 686 687/* 688 * Check that a proposed value to load into the .it_value or 689 * .it_interval part of an interval timer is acceptable, and 690 * fix it to have at least minimal value (i.e. if it is less 691 * than the resolution of the clock, round it up.) 692 */ 693int 694itimerfix(struct timeval *tv) 695{ 696 697 if (tv->tv_sec < 0 || tv->tv_usec < 0 || tv->tv_usec >= 1000000) 698 return (EINVAL); 699 if (tv->tv_sec == 0 && tv->tv_usec != 0 && tv->tv_usec < tick) 700 tv->tv_usec = tick; 701 return (0); 702} 703 704/* 705 * Decrement an interval timer by a specified number 706 * of microseconds, which must be less than a second, 707 * i.e. < 1000000. If the timer expires, then reload 708 * it. In this case, carry over (usec - old value) to 709 * reduce the value reloaded into the timer so that 710 * the timer does not drift. This routine assumes 711 * that it is called in a context where the timers 712 * on which it is operating cannot change in value. 713 */ 714int 715itimerdecr(struct itimerval *itp, int usec) 716{ 717 718 if (itp->it_value.tv_usec < usec) { 719 if (itp->it_value.tv_sec == 0) { 720 /* expired, and already in next interval */ 721 usec -= itp->it_value.tv_usec; 722 goto expire; 723 } 724 itp->it_value.tv_usec += 1000000; 725 itp->it_value.tv_sec--; 726 } 727 itp->it_value.tv_usec -= usec; 728 usec = 0; 729 if (timevalisset(&itp->it_value)) 730 return (1); 731 /* expired, exactly at end of interval */ 732expire: 733 if (timevalisset(&itp->it_interval)) { 734 itp->it_value = itp->it_interval; 735 itp->it_value.tv_usec -= usec; 736 if (itp->it_value.tv_usec < 0) { 737 itp->it_value.tv_usec += 1000000; 738 itp->it_value.tv_sec--; 739 } 740 } else 741 itp->it_value.tv_usec = 0; /* sec is already 0 */ 742 return (0); 743} 744 745/* 746 * Add and subtract routines for timevals. 747 * N.B.: subtract routine doesn't deal with 748 * results which are before the beginning, 749 * it just gets very confused in this case. 750 * Caveat emptor. 751 */ 752void 753timevaladd(struct timeval *t1, const struct timeval *t2) 754{ 755 756 t1->tv_sec += t2->tv_sec; 757 t1->tv_usec += t2->tv_usec; 758 timevalfix(t1); 759} 760 761void 762timevalsub(struct timeval *t1, const struct timeval *t2) 763{ 764 765 t1->tv_sec -= t2->tv_sec; 766 t1->tv_usec -= t2->tv_usec; 767 timevalfix(t1); 768} 769 770static void 771timevalfix(struct timeval *t1) 772{ 773 774 if (t1->tv_usec < 0) { 775 t1->tv_sec--; 776 t1->tv_usec += 1000000; 777 } 778 if (t1->tv_usec >= 1000000) { 779 t1->tv_sec++; 780 t1->tv_usec -= 1000000; 781 } 782} 783 784/* 785 * ratecheck(): simple time-based rate-limit checking. 786 */ 787int 788ratecheck(struct timeval *lasttime, const struct timeval *mininterval) 789{ 790 struct timeval tv, delta; 791 int rv = 0; 792 793 getmicrouptime(&tv); /* NB: 10ms precision */ 794 delta = tv; 795 timevalsub(&delta, lasttime); 796 797 /* 798 * check for 0,0 is so that the message will be seen at least once, 799 * even if interval is huge. 800 */ 801 if (timevalcmp(&delta, mininterval, >=) || 802 (lasttime->tv_sec == 0 && lasttime->tv_usec == 0)) { 803 *lasttime = tv; 804 rv = 1; 805 } 806 807 return (rv); 808} 809 810/* 811 * ppsratecheck(): packets (or events) per second limitation. 812 * 813 * Return 0 if the limit is to be enforced (e.g. the caller 814 * should drop a packet because of the rate limitation). 815 * 816 * maxpps of 0 always causes zero to be returned. maxpps of -1 817 * always causes 1 to be returned; this effectively defeats rate 818 * limiting. 819 * 820 * Note that we maintain the struct timeval for compatibility 821 * with other bsd systems. We reuse the storage and just monitor 822 * clock ticks for minimal overhead. 823 */ 824int 825ppsratecheck(struct timeval *lasttime, int *curpps, int maxpps) 826{ 827 int now; 828 829 /* 830 * Reset the last time and counter if this is the first call 831 * or more than a second has passed since the last update of 832 * lasttime. 833 */ 834 now = ticks; 835 if (lasttime->tv_sec == 0 || (u_int)(now - lasttime->tv_sec) >= hz) { 836 lasttime->tv_sec = now; 837 *curpps = 1; 838 return (maxpps != 0); 839 } else { 840 (*curpps)++; /* NB: ignore potential overflow */ 841 return (maxpps < 0 || *curpps < maxpps); 842 } 843} 844 845static void 846itimer_start(void) 847{ 848 struct kclock rt_clock = { 849 .timer_create = realtimer_create, 850 .timer_delete = realtimer_delete, 851 .timer_settime = realtimer_settime, 852 .timer_gettime = realtimer_gettime, 853 .event_hook = NULL 854 }; 855 856 itimer_zone = uma_zcreate("itimer", sizeof(struct itimer), 857 NULL, NULL, itimer_init, itimer_fini, UMA_ALIGN_PTR, 0); 858 register_posix_clock(CLOCK_REALTIME, &rt_clock); 859 register_posix_clock(CLOCK_MONOTONIC, &rt_clock); 860 p31b_setcfg(CTL_P1003_1B_TIMERS, 200112L); 861 p31b_setcfg(CTL_P1003_1B_DELAYTIMER_MAX, INT_MAX); 862 p31b_setcfg(CTL_P1003_1B_TIMER_MAX, TIMER_MAX); 863 EVENTHANDLER_REGISTER(process_exit, itimers_event_hook_exit, 864 (void *)ITIMER_EV_EXIT, EVENTHANDLER_PRI_ANY); 865 EVENTHANDLER_REGISTER(process_exec, itimers_event_hook_exec, 866 (void *)ITIMER_EV_EXEC, EVENTHANDLER_PRI_ANY); 867} 868 869int 870register_posix_clock(int clockid, struct kclock *clk) 871{ 872 if ((unsigned)clockid >= MAX_CLOCKS) { 873 printf("%s: invalid clockid\n", __func__); 874 return (0); 875 } 876 posix_clocks[clockid] = *clk; 877 return (1); 878} 879 880static int 881itimer_init(void *mem, int size, int flags) 882{ 883 struct itimer *it; 884 885 it = (struct itimer *)mem; 886 mtx_init(&it->it_mtx, "itimer lock", NULL, MTX_DEF); 887 return (0); 888} 889 890static void 891itimer_fini(void *mem, int size) 892{ 893 struct itimer *it; 894 895 it = (struct itimer *)mem; 896 mtx_destroy(&it->it_mtx); 897} 898 899static void 900itimer_enter(struct itimer *it) 901{ 902 903 mtx_assert(&it->it_mtx, MA_OWNED); 904 it->it_usecount++; 905} 906 907static void 908itimer_leave(struct itimer *it) 909{ 910 911 mtx_assert(&it->it_mtx, MA_OWNED); 912 KASSERT(it->it_usecount > 0, ("invalid it_usecount")); 913 914 if (--it->it_usecount == 0 && (it->it_flags & ITF_WANTED) != 0) 915 wakeup(it); 916} 917 918#ifndef _SYS_SYSPROTO_H_ 919struct ktimer_create_args { 920 clockid_t clock_id; 921 struct sigevent * evp; 922 int * timerid; 923}; 924#endif 925int 926sys_ktimer_create(struct thread *td, struct ktimer_create_args *uap) 927{ 928 struct sigevent *evp1, ev; 929 int id; 930 int error; 931 932 if (uap->evp != NULL) { 933 error = copyin(uap->evp, &ev, sizeof(ev)); 934 if (error != 0) 935 return (error); 936 evp1 = &ev; 937 } else 938 evp1 = NULL; 939 940 error = kern_timer_create(td, uap->clock_id, evp1, &id, -1); 941 942 if (error == 0) { 943 error = copyout(&id, uap->timerid, sizeof(int)); 944 if (error != 0) 945 kern_timer_delete(td, id); 946 } 947 return (error); 948} 949 950static int 951kern_timer_create(struct thread *td, clockid_t clock_id, 952 struct sigevent *evp, int *timerid, int preset_id) 953{ 954 struct proc *p = td->td_proc; 955 struct itimer *it; 956 int id; 957 int error; 958 959 if (clock_id < 0 || clock_id >= MAX_CLOCKS) 960 return (EINVAL); 961 962 if (posix_clocks[clock_id].timer_create == NULL) 963 return (EINVAL); 964 965 if (evp != NULL) { 966 if (evp->sigev_notify != SIGEV_NONE && 967 evp->sigev_notify != SIGEV_SIGNAL && 968 evp->sigev_notify != SIGEV_THREAD_ID) 969 return (EINVAL); 970 if ((evp->sigev_notify == SIGEV_SIGNAL || 971 evp->sigev_notify == SIGEV_THREAD_ID) && 972 !_SIG_VALID(evp->sigev_signo)) 973 return (EINVAL); 974 } 975 976 if (p->p_itimers == NULL) 977 itimers_alloc(p); 978 979 it = uma_zalloc(itimer_zone, M_WAITOK); 980 it->it_flags = 0; 981 it->it_usecount = 0; 982 it->it_active = 0; 983 timespecclear(&it->it_time.it_value); 984 timespecclear(&it->it_time.it_interval); 985 it->it_overrun = 0; 986 it->it_overrun_last = 0; 987 it->it_clockid = clock_id; 988 it->it_timerid = -1; 989 it->it_proc = p; 990 ksiginfo_init(&it->it_ksi); 991 it->it_ksi.ksi_flags |= KSI_INS | KSI_EXT; 992 error = CLOCK_CALL(clock_id, timer_create, (it)); 993 if (error != 0) 994 goto out; 995 996 PROC_LOCK(p); 997 if (preset_id != -1) { 998 KASSERT(preset_id >= 0 && preset_id < 3, ("invalid preset_id")); 999 id = preset_id; 1000 if (p->p_itimers->its_timers[id] != NULL) { 1001 PROC_UNLOCK(p); 1002 error = 0; 1003 goto out; 1004 } 1005 } else { 1006 /* 1007 * Find a free timer slot, skipping those reserved 1008 * for setitimer(). 1009 */ 1010 for (id = 3; id < TIMER_MAX; id++) 1011 if (p->p_itimers->its_timers[id] == NULL) 1012 break; 1013 if (id == TIMER_MAX) { 1014 PROC_UNLOCK(p); 1015 error = EAGAIN; 1016 goto out; 1017 } 1018 } 1019 it->it_timerid = id; 1020 p->p_itimers->its_timers[id] = it; 1021 if (evp != NULL) 1022 it->it_sigev = *evp; 1023 else { 1024 it->it_sigev.sigev_notify = SIGEV_SIGNAL; 1025 switch (clock_id) { 1026 default: 1027 case CLOCK_REALTIME: 1028 it->it_sigev.sigev_signo = SIGALRM; 1029 break; 1030 case CLOCK_VIRTUAL: 1031 it->it_sigev.sigev_signo = SIGVTALRM; 1032 break; 1033 case CLOCK_PROF: 1034 it->it_sigev.sigev_signo = SIGPROF; 1035 break; 1036 } 1037 it->it_sigev.sigev_value.sival_int = id; 1038 } 1039 1040 if (it->it_sigev.sigev_notify == SIGEV_SIGNAL || 1041 it->it_sigev.sigev_notify == SIGEV_THREAD_ID) { 1042 it->it_ksi.ksi_signo = it->it_sigev.sigev_signo; 1043 it->it_ksi.ksi_code = SI_TIMER; 1044 it->it_ksi.ksi_value = it->it_sigev.sigev_value; 1045 it->it_ksi.ksi_timerid = id; 1046 } 1047 PROC_UNLOCK(p); 1048 *timerid = id; 1049 return (0); 1050 1051out: 1052 ITIMER_LOCK(it); 1053 CLOCK_CALL(it->it_clockid, timer_delete, (it)); 1054 ITIMER_UNLOCK(it); 1055 uma_zfree(itimer_zone, it); 1056 return (error); 1057} 1058 1059#ifndef _SYS_SYSPROTO_H_ 1060struct ktimer_delete_args { 1061 int timerid; 1062}; 1063#endif 1064int 1065sys_ktimer_delete(struct thread *td, struct ktimer_delete_args *uap) 1066{ 1067 return (kern_timer_delete(td, uap->timerid)); 1068} 1069 1070static struct itimer * 1071itimer_find(struct proc *p, int timerid) 1072{ 1073 struct itimer *it; 1074 1075 PROC_LOCK_ASSERT(p, MA_OWNED); 1076 if ((p->p_itimers == NULL) || 1077 (timerid < 0) || (timerid >= TIMER_MAX) || 1078 (it = p->p_itimers->its_timers[timerid]) == NULL) { 1079 return (NULL); 1080 } 1081 ITIMER_LOCK(it); 1082 if ((it->it_flags & ITF_DELETING) != 0) { 1083 ITIMER_UNLOCK(it); 1084 it = NULL; 1085 } 1086 return (it); 1087} 1088 1089static int 1090kern_timer_delete(struct thread *td, int timerid) 1091{ 1092 struct proc *p = td->td_proc; 1093 struct itimer *it; 1094 1095 PROC_LOCK(p); 1096 it = itimer_find(p, timerid); 1097 if (it == NULL) { 1098 PROC_UNLOCK(p); 1099 return (EINVAL); 1100 } 1101 PROC_UNLOCK(p); 1102 1103 it->it_flags |= ITF_DELETING; 1104 while (it->it_usecount > 0) { 1105 it->it_flags |= ITF_WANTED; 1106 msleep(it, &it->it_mtx, PPAUSE, "itimer", 0); 1107 } 1108 it->it_flags &= ~ITF_WANTED; 1109 CLOCK_CALL(it->it_clockid, timer_delete, (it)); 1110 ITIMER_UNLOCK(it); 1111 1112 PROC_LOCK(p); 1113 if (KSI_ONQ(&it->it_ksi)) 1114 sigqueue_take(&it->it_ksi); 1115 p->p_itimers->its_timers[timerid] = NULL; 1116 PROC_UNLOCK(p); 1117 uma_zfree(itimer_zone, it); 1118 return (0); 1119} 1120 1121#ifndef _SYS_SYSPROTO_H_ 1122struct ktimer_settime_args { 1123 int timerid; 1124 int flags; 1125 const struct itimerspec * value; 1126 struct itimerspec * ovalue; 1127}; 1128#endif 1129int 1130sys_ktimer_settime(struct thread *td, struct ktimer_settime_args *uap) 1131{ 1132 struct proc *p = td->td_proc; 1133 struct itimer *it; 1134 struct itimerspec val, oval, *ovalp; 1135 int error; 1136 1137 error = copyin(uap->value, &val, sizeof(val)); 1138 if (error != 0) 1139 return (error); 1140 1141 if (uap->ovalue != NULL) 1142 ovalp = &oval; 1143 else 1144 ovalp = NULL; 1145 1146 PROC_LOCK(p); 1147 if (uap->timerid < 3 || 1148 (it = itimer_find(p, uap->timerid)) == NULL) { 1149 PROC_UNLOCK(p); 1150 error = EINVAL; 1151 } else { 1152 PROC_UNLOCK(p); 1153 itimer_enter(it); 1154 error = CLOCK_CALL(it->it_clockid, timer_settime, 1155 (it, uap->flags, &val, ovalp)); 1156 itimer_leave(it); 1157 ITIMER_UNLOCK(it); 1158 } 1159 if (error == 0 && uap->ovalue != NULL) 1160 error = copyout(ovalp, uap->ovalue, sizeof(*ovalp)); 1161 return (error); 1162} 1163 1164#ifndef _SYS_SYSPROTO_H_ 1165struct ktimer_gettime_args { 1166 int timerid; 1167 struct itimerspec * value; 1168}; 1169#endif 1170int 1171sys_ktimer_gettime(struct thread *td, struct ktimer_gettime_args *uap) 1172{ 1173 struct proc *p = td->td_proc; 1174 struct itimer *it; 1175 struct itimerspec val; 1176 int error; 1177 1178 PROC_LOCK(p); 1179 if (uap->timerid < 3 || 1180 (it = itimer_find(p, uap->timerid)) == NULL) { 1181 PROC_UNLOCK(p); 1182 error = EINVAL; 1183 } else { 1184 PROC_UNLOCK(p); 1185 itimer_enter(it); 1186 error = CLOCK_CALL(it->it_clockid, timer_gettime, 1187 (it, &val)); 1188 itimer_leave(it); 1189 ITIMER_UNLOCK(it); 1190 } 1191 if (error == 0) 1192 error = copyout(&val, uap->value, sizeof(val)); 1193 return (error); 1194} 1195 1196#ifndef _SYS_SYSPROTO_H_ 1197struct timer_getoverrun_args { 1198 int timerid; 1199}; 1200#endif 1201int 1202sys_ktimer_getoverrun(struct thread *td, struct ktimer_getoverrun_args *uap) 1203{ 1204 struct proc *p = td->td_proc; 1205 struct itimer *it; 1206 int error ; 1207 1208 PROC_LOCK(p); 1209 if (uap->timerid < 3 || 1210 (it = itimer_find(p, uap->timerid)) == NULL) { 1211 PROC_UNLOCK(p); 1212 error = EINVAL; 1213 } else { 1214 td->td_retval[0] = it->it_overrun_last; 1215 ITIMER_UNLOCK(it); 1216 PROC_UNLOCK(p); 1217 error = 0; 1218 } 1219 return (error); 1220} 1221 1222static int 1223realtimer_create(struct itimer *it) 1224{ 1225 callout_init_mtx(&it->it_callout, &it->it_mtx, 0); 1226 return (0); 1227} 1228 1229static int 1230realtimer_delete(struct itimer *it) 1231{ 1232 mtx_assert(&it->it_mtx, MA_OWNED); 1233 1234 /* 1235 * clear timer's value and interval to tell realtimer_expire 1236 * to not rearm the timer. 1237 */ 1238 timespecclear(&it->it_time.it_value); 1239 timespecclear(&it->it_time.it_interval); 1240 ITIMER_UNLOCK(it); 1241 callout_drain(&it->it_callout); 1242 ITIMER_LOCK(it); 1243 return (0); 1244} 1245 1246static int 1247realtimer_gettime(struct itimer *it, struct itimerspec *ovalue) 1248{ 1249 struct timespec cts; 1250 1251 mtx_assert(&it->it_mtx, MA_OWNED); 1252 1253 realtimer_clocktime(it->it_clockid, &cts); 1254 *ovalue = it->it_time; 1255 if (ovalue->it_value.tv_sec != 0 || ovalue->it_value.tv_nsec != 0) { 1256 timespecsub(&ovalue->it_value, &cts); 1257 if (ovalue->it_value.tv_sec < 0 || 1258 (ovalue->it_value.tv_sec == 0 && 1259 ovalue->it_value.tv_nsec == 0)) { 1260 ovalue->it_value.tv_sec = 0; 1261 ovalue->it_value.tv_nsec = 1; 1262 } 1263 } 1264 return (0); 1265} 1266 1267static int 1268realtimer_settime(struct itimer *it, int flags, 1269 struct itimerspec *value, struct itimerspec *ovalue) 1270{ 1271 struct timespec cts, ts; 1272 struct timeval tv; 1273 struct itimerspec val; 1274 1275 mtx_assert(&it->it_mtx, MA_OWNED); 1276 1277 val = *value; 1278 if (itimespecfix(&val.it_value)) 1279 return (EINVAL); 1280 1281 if (timespecisset(&val.it_value)) { 1282 if (itimespecfix(&val.it_interval)) 1283 return (EINVAL); 1284 } else { 1285 timespecclear(&val.it_interval); 1286 } 1287 1288 if (ovalue != NULL) 1289 realtimer_gettime(it, ovalue); 1290 1291 it->it_time = val; 1292 if (timespecisset(&val.it_value)) { 1293 realtimer_clocktime(it->it_clockid, &cts); 1294 ts = val.it_value; 1295 if ((flags & TIMER_ABSTIME) == 0) { 1296 /* Convert to absolute time. */ 1297 timespecadd(&it->it_time.it_value, &cts); 1298 } else { 1299 timespecsub(&ts, &cts); 1300 /* 1301 * We don't care if ts is negative, tztohz will 1302 * fix it. 1303 */ 1304 } 1305 TIMESPEC_TO_TIMEVAL(&tv, &ts); 1306 callout_reset(&it->it_callout, tvtohz(&tv), 1307 realtimer_expire, it); 1308 } else { 1309 callout_stop(&it->it_callout); 1310 } 1311 1312 return (0); 1313} 1314 1315static void 1316realtimer_clocktime(clockid_t id, struct timespec *ts) 1317{ 1318 if (id == CLOCK_REALTIME) 1319 getnanotime(ts); 1320 else /* CLOCK_MONOTONIC */ 1321 getnanouptime(ts); 1322} 1323 1324int 1325itimer_accept(struct proc *p, int timerid, ksiginfo_t *ksi) 1326{ 1327 struct itimer *it; 1328 1329 PROC_LOCK_ASSERT(p, MA_OWNED); 1330 it = itimer_find(p, timerid); 1331 if (it != NULL) { 1332 ksi->ksi_overrun = it->it_overrun; 1333 it->it_overrun_last = it->it_overrun; 1334 it->it_overrun = 0; 1335 ITIMER_UNLOCK(it); 1336 return (0); 1337 } 1338 return (EINVAL); 1339} 1340 1341int 1342itimespecfix(struct timespec *ts) 1343{ 1344 1345 if (ts->tv_sec < 0 || ts->tv_nsec < 0 || ts->tv_nsec >= 1000000000) 1346 return (EINVAL); 1347 if (ts->tv_sec == 0 && ts->tv_nsec != 0 && ts->tv_nsec < tick * 1000) 1348 ts->tv_nsec = tick * 1000; 1349 return (0); 1350} 1351 1352/* Timeout callback for realtime timer */ 1353static void 1354realtimer_expire(void *arg) 1355{ 1356 struct timespec cts, ts; 1357 struct timeval tv; 1358 struct itimer *it; 1359 1360 it = (struct itimer *)arg; 1361 1362 realtimer_clocktime(it->it_clockid, &cts); 1363 /* Only fire if time is reached. */ 1364 if (timespeccmp(&cts, &it->it_time.it_value, >=)) { 1365 if (timespecisset(&it->it_time.it_interval)) { 1366 timespecadd(&it->it_time.it_value, 1367 &it->it_time.it_interval); 1368 while (timespeccmp(&cts, &it->it_time.it_value, >=)) { 1369 if (it->it_overrun < INT_MAX) 1370 it->it_overrun++; 1371 else 1372 it->it_ksi.ksi_errno = ERANGE; 1373 timespecadd(&it->it_time.it_value, 1374 &it->it_time.it_interval); 1375 } 1376 } else { 1377 /* single shot timer ? */ 1378 timespecclear(&it->it_time.it_value); 1379 } 1380 if (timespecisset(&it->it_time.it_value)) { 1381 ts = it->it_time.it_value; 1382 timespecsub(&ts, &cts); 1383 TIMESPEC_TO_TIMEVAL(&tv, &ts); 1384 callout_reset(&it->it_callout, tvtohz(&tv), 1385 realtimer_expire, it); 1386 } 1387 itimer_enter(it); 1388 ITIMER_UNLOCK(it); 1389 itimer_fire(it); 1390 ITIMER_LOCK(it); 1391 itimer_leave(it); 1392 } else if (timespecisset(&it->it_time.it_value)) { 1393 ts = it->it_time.it_value; 1394 timespecsub(&ts, &cts); 1395 TIMESPEC_TO_TIMEVAL(&tv, &ts); 1396 callout_reset(&it->it_callout, tvtohz(&tv), realtimer_expire, 1397 it); 1398 } 1399} 1400 1401void 1402itimer_fire(struct itimer *it) 1403{ 1404 struct proc *p = it->it_proc; 1405 struct thread *td; 1406 1407 if (it->it_sigev.sigev_notify == SIGEV_SIGNAL || 1408 it->it_sigev.sigev_notify == SIGEV_THREAD_ID) { 1409 if (sigev_findtd(p, &it->it_sigev, &td) != 0) { 1410 ITIMER_LOCK(it); 1411 timespecclear(&it->it_time.it_value); 1412 timespecclear(&it->it_time.it_interval); 1413 callout_stop(&it->it_callout); 1414 ITIMER_UNLOCK(it); 1415 return; 1416 } 1417 if (!KSI_ONQ(&it->it_ksi)) { 1418 it->it_ksi.ksi_errno = 0; 1419 ksiginfo_set_sigev(&it->it_ksi, &it->it_sigev); 1420 tdsendsignal(p, td, it->it_ksi.ksi_signo, &it->it_ksi); 1421 } else { 1422 if (it->it_overrun < INT_MAX) 1423 it->it_overrun++; 1424 else 1425 it->it_ksi.ksi_errno = ERANGE; 1426 } 1427 PROC_UNLOCK(p); 1428 } 1429} 1430 1431static void 1432itimers_alloc(struct proc *p) 1433{ 1434 struct itimers *its; 1435 int i; 1436 1437 its = malloc(sizeof (struct itimers), M_SUBPROC, M_WAITOK | M_ZERO); 1438 LIST_INIT(&its->its_virtual); 1439 LIST_INIT(&its->its_prof); 1440 TAILQ_INIT(&its->its_worklist); 1441 for (i = 0; i < TIMER_MAX; i++) 1442 its->its_timers[i] = NULL; 1443 PROC_LOCK(p); 1444 if (p->p_itimers == NULL) { 1445 p->p_itimers = its; 1446 PROC_UNLOCK(p); 1447 } 1448 else { 1449 PROC_UNLOCK(p); 1450 free(its, M_SUBPROC); 1451 } 1452} 1453 1454static void 1455itimers_event_hook_exec(void *arg, struct proc *p, struct image_params *imgp __unused) 1456{ 1457 itimers_event_hook_exit(arg, p); 1458} 1459 1460/* Clean up timers when some process events are being triggered. */ 1461static void 1462itimers_event_hook_exit(void *arg, struct proc *p) 1463{ 1464 struct itimers *its; 1465 struct itimer *it; 1466 int event = (int)(intptr_t)arg; 1467 int i; 1468 1469 if (p->p_itimers != NULL) { 1470 its = p->p_itimers; 1471 for (i = 0; i < MAX_CLOCKS; ++i) { 1472 if (posix_clocks[i].event_hook != NULL) 1473 CLOCK_CALL(i, event_hook, (p, i, event)); 1474 } 1475 /* 1476 * According to susv3, XSI interval timers should be inherited 1477 * by new image. 1478 */ 1479 if (event == ITIMER_EV_EXEC) 1480 i = 3; 1481 else if (event == ITIMER_EV_EXIT) 1482 i = 0; 1483 else 1484 panic("unhandled event"); 1485 for (; i < TIMER_MAX; ++i) { 1486 if ((it = its->its_timers[i]) != NULL) 1487 kern_timer_delete(curthread, i); 1488 } 1489 if (its->its_timers[0] == NULL && 1490 its->its_timers[1] == NULL && 1491 its->its_timers[2] == NULL) { 1492 free(its, M_SUBPROC); 1493 p->p_itimers = NULL; 1494 } 1495 } 1496} 1497