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 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 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 * $FreeBSD: src/sys/kern/kern_time.c,v 1.68.2.1 2002/10/01 08:00:41 bde Exp $ 31 */ 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/buf.h> 36 #include <sys/sysmsg.h> 37 #include <sys/resourcevar.h> 38 #include <sys/signalvar.h> 39 #include <sys/kernel.h> 40 #include <sys/sysent.h> 41 #include <sys/proc.h> 42 #include <sys/priv.h> 43 #include <sys/time.h> 44 #include <sys/vnode.h> 45 #include <sys/sysctl.h> 46 #include <sys/kern_syscall.h> 47 #include <sys/upmap.h> 48 #include <vm/vm.h> 49 #include <vm/vm_extern.h> 50 51 #include <sys/msgport2.h> 52 #include <sys/spinlock2.h> 53 #include <sys/thread2.h> 54 55 extern struct spinlock ntp_spin; 56 57 #define CPUCLOCK_BIT 0x80000000 58 #define CPUCLOCK_ID_MASK ~CPUCLOCK_BIT 59 #define CPUCLOCK2LWPID(clock_id) (((clockid_t)(clock_id) >> 32) & CPUCLOCK_ID_MASK) 60 #define CPUCLOCK2PID(clock_id) ((clock_id) & CPUCLOCK_ID_MASK) 61 #define MAKE_CPUCLOCK(pid, lwp_id) ((clockid_t)(lwp_id) << 32 | (pid) | CPUCLOCK_BIT) 62 63 struct timezone tz; 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 75 static int settime(struct timeval *); 76 static void timevalfix(struct timeval *); 77 static void realitexpire(void *arg); 78 79 static int sysctl_gettimeofday_quick(SYSCTL_HANDLER_ARGS); 80 81 82 /* 83 * Nanosleep tries very hard to sleep for a precisely requested time 84 * interval, down to 1uS. The administrator can impose a minimum delay 85 * and a delay below which we hard-loop instead of initiate a timer 86 * interrupt and sleep. 87 * 88 * For machines under high loads it might be beneficial to increase min_us 89 * to e.g. 1000uS (1ms) so spining processes sleep meaningfully. 90 */ 91 static int nanosleep_min_us = 10; 92 static int nanosleep_hard_us = 100; 93 static int gettimeofday_quick = 0; 94 SYSCTL_INT(_kern, OID_AUTO, nanosleep_min_us, CTLFLAG_RW, 95 &nanosleep_min_us, 0, ""); 96 SYSCTL_INT(_kern, OID_AUTO, nanosleep_hard_us, CTLFLAG_RW, 97 &nanosleep_hard_us, 0, ""); 98 SYSCTL_PROC(_kern, OID_AUTO, gettimeofday_quick, CTLTYPE_INT | CTLFLAG_RW, 99 0, 0, sysctl_gettimeofday_quick, "I", "Quick mode gettimeofday"); 100 101 static struct lock masterclock_lock = LOCK_INITIALIZER("mstrclk", 0, 0); 102 103 static int 104 settime(struct timeval *tv) 105 { 106 struct timeval delta, tv1, tv2; 107 static struct timeval maxtime, laststep; 108 struct timespec ts; 109 int origcpu; 110 111 if ((origcpu = mycpu->gd_cpuid) != 0) 112 lwkt_setcpu_self(globaldata_find(0)); 113 114 crit_enter(); 115 microtime(&tv1); 116 delta = *tv; 117 timevalsub(&delta, &tv1); 118 119 /* 120 * If the system is secure, we do not allow the time to be 121 * set to a value earlier than 1 second less than the highest 122 * time we have yet seen. The worst a miscreant can do in 123 * this circumstance is "freeze" time. He couldn't go 124 * back to the past. 125 * 126 * We similarly do not allow the clock to be stepped more 127 * than one second, nor more than once per second. This allows 128 * a miscreant to make the clock march double-time, but no worse. 129 */ 130 if (securelevel > 1) { 131 if (delta.tv_sec < 0 || delta.tv_usec < 0) { 132 /* 133 * Update maxtime to latest time we've seen. 134 */ 135 if (tv1.tv_sec > maxtime.tv_sec) 136 maxtime = tv1; 137 tv2 = *tv; 138 timevalsub(&tv2, &maxtime); 139 if (tv2.tv_sec < -1) { 140 tv->tv_sec = maxtime.tv_sec - 1; 141 kprintf("Time adjustment clamped to -1 second\n"); 142 } 143 } else { 144 if (tv1.tv_sec == laststep.tv_sec) { 145 crit_exit(); 146 return (EPERM); 147 } 148 if (delta.tv_sec > 1) { 149 tv->tv_sec = tv1.tv_sec + 1; 150 kprintf("Time adjustment clamped to +1 second\n"); 151 } 152 laststep = *tv; 153 } 154 } 155 156 ts.tv_sec = tv->tv_sec; 157 ts.tv_nsec = tv->tv_usec * 1000; 158 set_timeofday(&ts); 159 crit_exit(); 160 161 if (origcpu != 0) 162 lwkt_setcpu_self(globaldata_find(origcpu)); 163 164 resettodr(); 165 return (0); 166 } 167 168 static void 169 get_process_cputime(struct proc *p, struct timespec *ats) 170 { 171 struct rusage ru; 172 173 lwkt_gettoken(&p->p_token); 174 calcru_proc(p, &ru); 175 lwkt_reltoken(&p->p_token); 176 timevaladd(&ru.ru_utime, &ru.ru_stime); 177 TIMEVAL_TO_TIMESPEC(&ru.ru_utime, ats); 178 } 179 180 static void 181 get_process_usertime(struct proc *p, struct timespec *ats) 182 { 183 struct rusage ru; 184 185 lwkt_gettoken(&p->p_token); 186 calcru_proc(p, &ru); 187 lwkt_reltoken(&p->p_token); 188 TIMEVAL_TO_TIMESPEC(&ru.ru_utime, ats); 189 } 190 191 static void 192 get_thread_cputime(struct thread *td, struct timespec *ats) 193 { 194 struct timeval sys, user; 195 196 calcru(td->td_lwp, &user, &sys); 197 timevaladd(&user, &sys); 198 TIMEVAL_TO_TIMESPEC(&user, ats); 199 } 200 201 /* 202 * MPSAFE 203 */ 204 int 205 kern_clock_gettime(clockid_t clock_id, struct timespec *ats) 206 { 207 struct proc *p; 208 struct lwp *lp; 209 lwpid_t lwp_id; 210 211 p = curproc; 212 switch(clock_id) { 213 case CLOCK_REALTIME: 214 case CLOCK_REALTIME_PRECISE: 215 nanotime(ats); 216 break; 217 case CLOCK_REALTIME_FAST: 218 getnanotime(ats); 219 break; 220 case CLOCK_MONOTONIC: 221 case CLOCK_MONOTONIC_PRECISE: 222 case CLOCK_UPTIME: 223 case CLOCK_UPTIME_PRECISE: 224 nanouptime(ats); 225 break; 226 case CLOCK_MONOTONIC_FAST: 227 case CLOCK_UPTIME_FAST: 228 getnanouptime(ats); 229 break; 230 case CLOCK_VIRTUAL: 231 get_process_usertime(p, ats); 232 break; 233 case CLOCK_PROF: 234 case CLOCK_PROCESS_CPUTIME_ID: 235 get_process_cputime(p, ats); 236 break; 237 case CLOCK_SECOND: 238 ats->tv_sec = time_second; 239 ats->tv_nsec = 0; 240 break; 241 case CLOCK_THREAD_CPUTIME_ID: 242 get_thread_cputime(curthread, ats); 243 break; 244 default: 245 if ((clock_id & CPUCLOCK_BIT) == 0) 246 return (EINVAL); 247 if ((p = pfind(CPUCLOCK2PID(clock_id))) == NULL) 248 return (EINVAL); 249 lwp_id = CPUCLOCK2LWPID(clock_id); 250 if (lwp_id == 0) { 251 get_process_cputime(p, ats); 252 } else { 253 lwkt_gettoken(&p->p_token); 254 lp = lwp_rb_tree_RB_LOOKUP(&p->p_lwp_tree, lwp_id); 255 if (lp == NULL) { 256 lwkt_reltoken(&p->p_token); 257 PRELE(p); 258 return (EINVAL); 259 } 260 get_thread_cputime(lp->lwp_thread, ats); 261 lwkt_reltoken(&p->p_token); 262 } 263 PRELE(p); 264 } 265 return (0); 266 } 267 268 /* 269 * MPSAFE 270 */ 271 int 272 sys_clock_gettime(struct sysmsg *sysmsg, const struct clock_gettime_args *uap) 273 { 274 struct timespec ats; 275 int error; 276 277 error = kern_clock_gettime(uap->clock_id, &ats); 278 if (error == 0) 279 error = copyout(&ats, uap->tp, sizeof(ats)); 280 281 return (error); 282 } 283 284 int 285 kern_clock_settime(clockid_t clock_id, struct timespec *ats) 286 { 287 struct thread *td = curthread; 288 struct timeval atv; 289 int error; 290 291 if ((error = priv_check(td, PRIV_CLOCK_SETTIME)) != 0) 292 return (error); 293 if (clock_id != CLOCK_REALTIME) 294 return (EINVAL); 295 if (ats->tv_sec < 0 || ats->tv_nsec < 0 || ats->tv_nsec >= 1000000000) 296 return (EINVAL); 297 298 lockmgr(&masterclock_lock, LK_EXCLUSIVE); 299 TIMESPEC_TO_TIMEVAL(&atv, ats); 300 error = settime(&atv); 301 lockmgr(&masterclock_lock, LK_RELEASE); 302 303 return (error); 304 } 305 306 /* 307 * MPALMOSTSAFE 308 */ 309 int 310 sys_clock_settime(struct sysmsg *sysmsg, const struct clock_settime_args *uap) 311 { 312 struct timespec ats; 313 int error; 314 315 if ((error = copyin(uap->tp, &ats, sizeof(ats))) != 0) 316 return (error); 317 318 error = kern_clock_settime(uap->clock_id, &ats); 319 320 return (error); 321 } 322 323 /* 324 * MPSAFE 325 */ 326 int 327 kern_clock_getres(clockid_t clock_id, struct timespec *ts) 328 { 329 ts->tv_sec = 0; 330 331 switch (clock_id) { 332 case CLOCK_REALTIME: 333 case CLOCK_REALTIME_FAST: 334 case CLOCK_REALTIME_PRECISE: 335 case CLOCK_MONOTONIC: 336 case CLOCK_MONOTONIC_FAST: 337 case CLOCK_MONOTONIC_PRECISE: 338 case CLOCK_UPTIME: 339 case CLOCK_UPTIME_FAST: 340 case CLOCK_UPTIME_PRECISE: 341 /* 342 * Minimum reportable resolution is 1ns. Rounding is 343 * otherwise unimportant. 344 */ 345 ts->tv_nsec = 999999999 / sys_cputimer->freq + 1; 346 break; 347 case CLOCK_VIRTUAL: 348 case CLOCK_PROF: 349 /* Accurately round up here because we can do so cheaply. */ 350 ts->tv_nsec = howmany(1000000000, hz); 351 break; 352 case CLOCK_SECOND: 353 ts->tv_sec = 1; 354 ts->tv_nsec = 0; 355 break; 356 case CLOCK_THREAD_CPUTIME_ID: 357 case CLOCK_PROCESS_CPUTIME_ID: 358 ts->tv_nsec = 1000; 359 break; 360 default: 361 if ((clock_id & CPUCLOCK_BIT) == CPUCLOCK_BIT) { 362 pid_t pid = CPUCLOCK2PID(clock_id); 363 if (pid < 2 || pid > PID_MAX) 364 return (EINVAL); 365 ts->tv_nsec = 1000; 366 } else { 367 return (EINVAL); 368 } 369 } 370 371 return (0); 372 } 373 374 /* 375 * MPSAFE 376 */ 377 int 378 sys_clock_getres(struct sysmsg *sysmsg, const struct clock_getres_args *uap) 379 { 380 int error; 381 struct timespec ts; 382 383 error = kern_clock_getres(uap->clock_id, &ts); 384 if (error == 0) 385 error = copyout(&ts, uap->tp, sizeof(ts)); 386 387 return (error); 388 } 389 390 static int 391 kern_getcpuclockid(pid_t pid, lwpid_t lwp_id, clockid_t *clock_id) 392 { 393 struct proc *p; 394 int error = 0; 395 396 if (pid == 0) { 397 p = curproc; 398 pid = p->p_pid; 399 PHOLD(p); 400 } else { 401 p = pfind(pid); 402 if (p == NULL) 403 return (ESRCH); 404 } 405 /* lwp_id can be 0 when called by clock_getcpuclockid() */ 406 if (lwp_id < 0) { 407 error = EINVAL; 408 goto out; 409 } 410 lwkt_gettoken(&p->p_token); 411 if (lwp_id > 0 && 412 lwp_rb_tree_RB_LOOKUP(&p->p_lwp_tree, lwp_id) == NULL) { 413 lwkt_reltoken(&p->p_token); 414 error = ESRCH; 415 goto out; 416 } 417 *clock_id = MAKE_CPUCLOCK(pid, lwp_id); 418 lwkt_reltoken(&p->p_token); 419 out: 420 PRELE(p); 421 return (error); 422 } 423 424 int 425 sys_getcpuclockid(struct sysmsg *sysmsg, const struct getcpuclockid_args *uap) 426 { 427 clockid_t clk_id; 428 int error; 429 430 error = kern_getcpuclockid(uap->pid, uap->lwp_id, &clk_id); 431 if (error == 0) 432 error = copyout(&clk_id, uap->clock_id, sizeof(clockid_t)); 433 434 return (error); 435 } 436 437 /* 438 * clock_nanosleep1() 439 * 440 * This is a general helper function for clock_nanosleep() and 441 * nanosleep() (aka sleep(), aka usleep()). 442 * 443 * If there is less than one tick's worth of time left and 444 * we haven't done a yield, or the remaining microseconds is 445 * ridiculously low, do a yield. This avoids having 446 * to deal with systimer overheads when the system is under 447 * heavy loads. If we have done a yield already then use 448 * a systimer and an uninterruptable thread wait. 449 * 450 * If there is more than a tick's worth of time left, 451 * calculate the baseline ticks and use an interruptable 452 * tsleep, then handle the fine-grained delay on the next 453 * loop. This usually results in two sleeps occuring, a long one 454 * and a short one. 455 * 456 * MPSAFE 457 */ 458 static void 459 ns1_systimer(systimer_t info, int in_ipi __unused, 460 struct intrframe *frame __unused) 461 { 462 lwkt_schedule(info->data); 463 } 464 465 int 466 clock_nanosleep1(clockid_t clock_id, int flags, 467 struct timespec *rqt, struct timespec *rmt) 468 { 469 static int nanowait; 470 struct timespec ts_cur, ts_tgt, ts_int; 471 struct timeval tv; 472 bool is_abs; 473 int error, error2; 474 475 if ((flags & ~(TIMER_RELTIME | TIMER_ABSTIME)) != 0) 476 return (EINVAL); 477 if (rqt->tv_sec < 0 || rqt->tv_nsec < 0 || rqt->tv_nsec >= 1000000000) 478 return (EINVAL); 479 if (rqt->tv_sec == 0 && rqt->tv_nsec == 0) 480 return (0); 481 482 switch (clock_id) { 483 case CLOCK_REALTIME: 484 case CLOCK_REALTIME_FAST: 485 case CLOCK_REALTIME_PRECISE: 486 case CLOCK_SECOND: 487 case CLOCK_MONOTONIC: 488 case CLOCK_MONOTONIC_FAST: 489 case CLOCK_MONOTONIC_PRECISE: 490 case CLOCK_UPTIME: 491 case CLOCK_UPTIME_FAST: 492 case CLOCK_UPTIME_PRECISE: 493 is_abs = (flags & TIMER_ABSTIME) != 0; 494 break; 495 case CLOCK_VIRTUAL: 496 case CLOCK_PROF: 497 case CLOCK_PROCESS_CPUTIME_ID: 498 return (ENOTSUP); 499 case CLOCK_THREAD_CPUTIME_ID: 500 default: 501 return (EINVAL); 502 } 503 504 error = kern_clock_gettime(clock_id, &ts_cur); 505 if (error) 506 return (error); 507 508 if (is_abs) { 509 if (timespeccmp(&ts_cur, rqt, >=)) 510 return (0); 511 512 ts_tgt = *rqt; /* target timestamp */ 513 timespecsub(&ts_tgt, &ts_cur, &ts_int); /* sleep interval */ 514 } else { 515 ts_int = *rqt; /* sleep interval */ 516 timespecadd(&ts_cur, &ts_int, &ts_tgt); /* target timestamp */ 517 } 518 519 for (;;) { 520 int ticks; 521 struct systimer info; 522 thread_t td; 523 524 timespecsub(&ts_tgt, &ts_cur, &ts_int); 525 TIMESPEC_TO_TIMEVAL(&tv, &ts_int); 526 ticks = tv.tv_usec / ustick; /* approximate */ 527 528 if (tv.tv_sec == 0 && ticks == 0) { 529 td = curthread; 530 if (tv.tv_usec > 0 && tv.tv_usec < nanosleep_min_us) 531 tv.tv_usec = nanosleep_min_us; 532 if (tv.tv_usec < nanosleep_hard_us) { 533 lwkt_user_yield(); 534 cpu_pause(); 535 } else { 536 crit_enter_quick(td); 537 systimer_init_oneshot(&info, ns1_systimer, 538 td, tv.tv_usec); 539 lwkt_deschedule_self(td); 540 crit_exit_quick(td); 541 lwkt_switch(); 542 systimer_del(&info); /* make sure it's gone */ 543 } 544 error = iscaught(td->td_lwp); 545 } else if (tv.tv_sec == 0) { 546 error = tsleep(&nanowait, PCATCH, "nanslp", ticks); 547 } else { 548 ticks = tvtohz_low(&tv); /* also handles overflow */ 549 error = tsleep(&nanowait, PCATCH, "nanslp", ticks); 550 } 551 552 error2 = kern_clock_gettime(clock_id, &ts_cur); 553 if (error2) 554 return (error2); 555 556 if (error && error != EWOULDBLOCK) { 557 if (error == ERESTART) 558 error = EINTR; 559 if (rmt != NULL && !is_abs) { 560 timespecsub(&ts_tgt, &ts_cur, &ts_int); 561 if (ts_int.tv_sec < 0) 562 timespecclear(&ts_int); 563 *rmt = ts_int; 564 } 565 return (error); 566 } 567 if (timespeccmp(&ts_cur, &ts_tgt, >=)) 568 return (0); 569 } 570 } 571 572 int 573 nanosleep1(struct timespec *rqt, struct timespec *rmt) 574 { 575 return clock_nanosleep1(CLOCK_REALTIME, TIMER_RELTIME, rqt, rmt); 576 } 577 578 /* 579 * MPSAFE 580 */ 581 int 582 sys_clock_nanosleep(struct sysmsg *sysmsg, 583 const struct clock_nanosleep_args *uap) 584 { 585 int error; 586 bool is_abs; 587 struct timespec rqt; 588 struct timespec rmt; 589 590 is_abs = (uap->flags & TIMER_ABSTIME) != 0; 591 592 error = copyin(uap->rqtp, &rqt, sizeof(rqt)); 593 if (error) { 594 sysmsg->sysmsg_result = error; 595 return (0); 596 } 597 598 bzero(&rmt, sizeof(rmt)); 599 error = clock_nanosleep1(uap->clock_id, uap->flags, &rqt, &rmt); 600 601 /* 602 * copyout the residual if nanosleep was interrupted. 603 */ 604 if (error == EINTR && uap->rmtp != NULL && !is_abs) { 605 int error2; 606 607 error2 = copyout(&rmt, uap->rmtp, sizeof(rmt)); 608 if (error2) 609 error = error2; 610 } 611 612 sysmsg->sysmsg_result = error; 613 return (0); 614 } 615 616 /* 617 * MPSAFE 618 */ 619 int 620 sys_nanosleep(struct sysmsg *sysmsg, const struct nanosleep_args *uap) 621 { 622 int error; 623 struct timespec rqt; 624 struct timespec rmt; 625 626 error = copyin(uap->rqtp, &rqt, sizeof(rqt)); 627 if (error) 628 return (error); 629 630 bzero(&rmt, sizeof(rmt)); 631 error = nanosleep1(&rqt, &rmt); 632 633 /* 634 * copyout the residual if nanosleep was interrupted. 635 */ 636 if (error == EINTR && uap->rmtp != NULL) { 637 int error2; 638 639 error2 = copyout(&rmt, uap->rmtp, sizeof(rmt)); 640 if (error2) 641 error = error2; 642 } 643 return (error); 644 } 645 646 /* 647 * The gettimeofday() system call is supposed to return a fine-grained 648 * realtime stamp. However, acquiring a fine-grained stamp can create a 649 * bottleneck when multiple cpu cores are trying to accessing e.g. the 650 * HPET hardware timer all at the same time, so we have a sysctl that 651 * allows its behavior to be changed to a more coarse-grained timestamp 652 * which does not have to access a hardware timer. 653 */ 654 int 655 sys_gettimeofday(struct sysmsg *sysmsg, const struct gettimeofday_args *uap) 656 { 657 struct timeval atv; 658 int error = 0; 659 660 if (uap->tp) { 661 if (gettimeofday_quick) 662 getmicrotime(&atv); 663 else 664 microtime(&atv); 665 if ((error = copyout((caddr_t)&atv, (caddr_t)uap->tp, 666 sizeof (atv)))) 667 return (error); 668 } 669 if (uap->tzp) 670 error = copyout((caddr_t)&tz, (caddr_t)uap->tzp, 671 sizeof (tz)); 672 return (error); 673 } 674 675 /* 676 * MPALMOSTSAFE 677 */ 678 int 679 sys_settimeofday(struct sysmsg *sysmsg, const struct settimeofday_args *uap) 680 { 681 struct thread *td = curthread; 682 struct timeval atv; 683 struct timezone atz; 684 int error; 685 686 if ((error = priv_check(td, PRIV_SETTIMEOFDAY))) 687 return (error); 688 /* 689 * Verify all parameters before changing time. 690 * 691 * XXX: We do not allow the time to be set to 0.0, which also by 692 * happy coincidence works around a pkgsrc bulk build bug. 693 */ 694 if (uap->tv) { 695 if ((error = copyin((caddr_t)uap->tv, (caddr_t)&atv, 696 sizeof(atv)))) 697 return (error); 698 if (atv.tv_usec < 0 || atv.tv_usec >= 1000000) 699 return (EINVAL); 700 if (atv.tv_sec == 0 && atv.tv_usec == 0) 701 return (EINVAL); 702 } 703 if (uap->tzp && 704 (error = copyin((caddr_t)uap->tzp, (caddr_t)&atz, sizeof(atz)))) 705 return (error); 706 707 lockmgr(&masterclock_lock, LK_EXCLUSIVE); 708 if (uap->tv && (error = settime(&atv))) { 709 lockmgr(&masterclock_lock, LK_RELEASE); 710 return (error); 711 } 712 lockmgr(&masterclock_lock, LK_RELEASE); 713 714 if (uap->tzp) 715 tz = atz; 716 return (0); 717 } 718 719 /* 720 * WARNING! Run with ntp_spin held 721 */ 722 static void 723 kern_adjtime_common(void) 724 { 725 if ((ntp_delta >= 0 && ntp_delta < ntp_default_tick_delta) || 726 (ntp_delta < 0 && ntp_delta > -ntp_default_tick_delta)) 727 ntp_tick_delta = ntp_delta; 728 else if (ntp_delta > ntp_big_delta) 729 ntp_tick_delta = 10 * ntp_default_tick_delta; 730 else if (ntp_delta < -ntp_big_delta) 731 ntp_tick_delta = -10 * ntp_default_tick_delta; 732 else if (ntp_delta > 0) 733 ntp_tick_delta = ntp_default_tick_delta; 734 else 735 ntp_tick_delta = -ntp_default_tick_delta; 736 } 737 738 void 739 kern_adjtime(int64_t delta, int64_t *odelta) 740 { 741 spin_lock(&ntp_spin); 742 *odelta = ntp_delta; 743 ntp_delta = delta; 744 kern_adjtime_common(); 745 spin_unlock(&ntp_spin); 746 } 747 748 static void 749 kern_get_ntp_delta(int64_t *delta) 750 { 751 *delta = ntp_delta; 752 } 753 754 void 755 kern_reladjtime(int64_t delta) 756 { 757 spin_lock(&ntp_spin); 758 ntp_delta += delta; 759 kern_adjtime_common(); 760 spin_unlock(&ntp_spin); 761 } 762 763 static void 764 kern_adjfreq(int64_t rate) 765 { 766 spin_lock(&ntp_spin); 767 ntp_tick_permanent = rate; 768 spin_unlock(&ntp_spin); 769 } 770 771 /* 772 * MPALMOSTSAFE 773 */ 774 int 775 sys_adjtime(struct sysmsg *sysmsg, const struct adjtime_args *uap) 776 { 777 struct thread *td = curthread; 778 struct timeval atv; 779 int64_t ndelta, odelta; 780 int error; 781 782 if ((error = priv_check(td, PRIV_ADJTIME))) 783 return (error); 784 error = copyin(uap->delta, &atv, sizeof(struct timeval)); 785 if (error) 786 return (error); 787 788 /* 789 * Compute the total correction and the rate at which to apply it. 790 * Round the adjustment down to a whole multiple of the per-tick 791 * delta, so that after some number of incremental changes in 792 * hardclock(), tickdelta will become zero, lest the correction 793 * overshoot and start taking us away from the desired final time. 794 */ 795 ndelta = (int64_t)atv.tv_sec * 1000000000 + atv.tv_usec * 1000; 796 kern_adjtime(ndelta, &odelta); 797 798 if (uap->olddelta) { 799 atv.tv_sec = odelta / 1000000000; 800 atv.tv_usec = odelta % 1000000000 / 1000; 801 copyout(&atv, uap->olddelta, sizeof(struct timeval)); 802 } 803 return (0); 804 } 805 806 static int 807 sysctl_adjtime(SYSCTL_HANDLER_ARGS) 808 { 809 int64_t delta; 810 int error; 811 812 if (req->newptr != NULL) { 813 if (priv_check(curthread, PRIV_ROOT)) 814 return (EPERM); 815 error = SYSCTL_IN(req, &delta, sizeof(delta)); 816 if (error) 817 return (error); 818 kern_reladjtime(delta); 819 } 820 821 if (req->oldptr) 822 kern_get_ntp_delta(&delta); 823 error = SYSCTL_OUT(req, &delta, sizeof(delta)); 824 return (error); 825 } 826 827 /* 828 * delta is in nanoseconds. 829 */ 830 static int 831 sysctl_delta(SYSCTL_HANDLER_ARGS) 832 { 833 int64_t delta, old_delta; 834 int error; 835 836 if (req->newptr != NULL) { 837 if (priv_check(curthread, PRIV_ROOT)) 838 return (EPERM); 839 error = SYSCTL_IN(req, &delta, sizeof(delta)); 840 if (error) 841 return (error); 842 kern_adjtime(delta, &old_delta); 843 } 844 845 if (req->oldptr != NULL) 846 kern_get_ntp_delta(&old_delta); 847 error = SYSCTL_OUT(req, &old_delta, sizeof(old_delta)); 848 return (error); 849 } 850 851 /* 852 * frequency is in nanoseconds per second shifted left 32. 853 * kern_adjfreq() needs it in nanoseconds per tick shifted left 32. 854 */ 855 static int 856 sysctl_adjfreq(SYSCTL_HANDLER_ARGS) 857 { 858 int64_t freqdelta; 859 int error; 860 861 if (req->newptr != NULL) { 862 if (priv_check(curthread, PRIV_ROOT)) 863 return (EPERM); 864 error = SYSCTL_IN(req, &freqdelta, sizeof(freqdelta)); 865 if (error) 866 return (error); 867 868 freqdelta /= hz; 869 kern_adjfreq(freqdelta); 870 } 871 872 if (req->oldptr != NULL) 873 freqdelta = ntp_tick_permanent * hz; 874 error = SYSCTL_OUT(req, &freqdelta, sizeof(freqdelta)); 875 if (error) 876 return (error); 877 878 return (0); 879 } 880 881 SYSCTL_NODE(_kern, OID_AUTO, ntp, CTLFLAG_RW, 0, "NTP related controls"); 882 SYSCTL_PROC(_kern_ntp, OID_AUTO, permanent, 883 CTLTYPE_QUAD|CTLFLAG_RW, 0, 0, 884 sysctl_adjfreq, "Q", "permanent correction per second"); 885 SYSCTL_PROC(_kern_ntp, OID_AUTO, delta, 886 CTLTYPE_QUAD|CTLFLAG_RW, 0, 0, 887 sysctl_delta, "Q", "one-time delta"); 888 SYSCTL_OPAQUE(_kern_ntp, OID_AUTO, big_delta, CTLFLAG_RD, 889 &ntp_big_delta, sizeof(ntp_big_delta), "Q", 890 "threshold for fast adjustment"); 891 SYSCTL_OPAQUE(_kern_ntp, OID_AUTO, tick_delta, CTLFLAG_RD, 892 &ntp_tick_delta, sizeof(ntp_tick_delta), "LU", 893 "per-tick adjustment"); 894 SYSCTL_OPAQUE(_kern_ntp, OID_AUTO, default_tick_delta, CTLFLAG_RD, 895 &ntp_default_tick_delta, sizeof(ntp_default_tick_delta), "LU", 896 "default per-tick adjustment"); 897 SYSCTL_OPAQUE(_kern_ntp, OID_AUTO, next_leap_second, CTLFLAG_RW, 898 &ntp_leap_second, sizeof(ntp_leap_second), "LU", 899 "next leap second"); 900 SYSCTL_INT(_kern_ntp, OID_AUTO, insert_leap_second, CTLFLAG_RW, 901 &ntp_leap_insert, 0, "insert or remove leap second"); 902 SYSCTL_PROC(_kern_ntp, OID_AUTO, adjust, 903 CTLTYPE_QUAD|CTLFLAG_RW, 0, 0, 904 sysctl_adjtime, "Q", "relative adjust for delta"); 905 906 /* 907 * Get value of an interval timer. The process virtual and 908 * profiling virtual time timers are kept in the p_stats area, since 909 * they can be swapped out. These are kept internally in the 910 * way they are specified externally: in time until they expire. 911 * 912 * The real time interval timer is kept in the process table slot 913 * for the process, and its value (it_value) is kept as an 914 * absolute time rather than as a delta, so that it is easy to keep 915 * periodic real-time signals from drifting. 916 * 917 * Virtual time timers are processed in the hardclock() routine of 918 * kern_clock.c. The real time timer is processed by a timeout 919 * routine, called from the softclock() routine. Since a callout 920 * may be delayed in real time due to interrupt processing in the system, 921 * it is possible for the real time timeout routine (realitexpire, given below), 922 * to be delayed in real time past when it is supposed to occur. It 923 * does not suffice, therefore, to reload the real timer .it_value from the 924 * real time timers .it_interval. Rather, we compute the next time in 925 * absolute time the timer should go off. 926 * 927 * MPALMOSTSAFE 928 */ 929 int 930 sys_getitimer(struct sysmsg *sysmsg, const struct getitimer_args *uap) 931 { 932 struct proc *p = curproc; 933 struct timeval ctv; 934 struct itimerval aitv; 935 936 if (uap->which > ITIMER_PROF) 937 return (EINVAL); 938 lwkt_gettoken(&p->p_token); 939 if (uap->which == ITIMER_REAL) { 940 /* 941 * Convert from absolute to relative time in .it_value 942 * part of real time timer. If time for real time timer 943 * has passed return 0, else return difference between 944 * current time and time for the timer to go off. 945 */ 946 aitv = p->p_realtimer; 947 if (timevalisset(&aitv.it_value)) { 948 getmicrouptime(&ctv); 949 if (timevalcmp(&aitv.it_value, &ctv, <)) 950 timevalclear(&aitv.it_value); 951 else 952 timevalsub(&aitv.it_value, &ctv); 953 } 954 } else { 955 aitv = p->p_timer[uap->which]; 956 } 957 lwkt_reltoken(&p->p_token); 958 return (copyout(&aitv, uap->itv, sizeof (struct itimerval))); 959 } 960 961 /* 962 * MPALMOSTSAFE 963 */ 964 int 965 sys_setitimer(struct sysmsg *sysmsg, const struct setitimer_args *uap) 966 { 967 struct itimerval aitv; 968 struct timeval ctv; 969 struct itimerval *itvp; 970 struct proc *p = curproc; 971 struct getitimer_args gitargs; 972 int error; 973 974 if (uap->which > ITIMER_PROF) 975 return (EINVAL); 976 itvp = uap->itv; 977 if (itvp && (error = copyin((caddr_t)itvp, (caddr_t)&aitv, 978 sizeof(struct itimerval)))) 979 return (error); 980 981 if (uap->oitv) { 982 gitargs.which = uap->which; 983 gitargs.itv = uap->oitv; 984 error = sys_getitimer(sysmsg, &gitargs); 985 if (error) 986 return error; 987 } 988 if (itvp == NULL) 989 return (0); 990 if (itimerfix(&aitv.it_value)) 991 return (EINVAL); 992 if (!timevalisset(&aitv.it_value)) 993 timevalclear(&aitv.it_interval); 994 else if (itimerfix(&aitv.it_interval)) 995 return (EINVAL); 996 lwkt_gettoken(&p->p_token); 997 if (uap->which == ITIMER_REAL) { 998 if (timevalisset(&p->p_realtimer.it_value)) 999 callout_cancel(&p->p_ithandle); 1000 if (timevalisset(&aitv.it_value)) 1001 callout_reset(&p->p_ithandle, 1002 tvtohz_high(&aitv.it_value), realitexpire, p); 1003 getmicrouptime(&ctv); 1004 timevaladd(&aitv.it_value, &ctv); 1005 p->p_realtimer = aitv; 1006 } else { 1007 p->p_timer[uap->which] = aitv; 1008 switch(uap->which) { 1009 case ITIMER_VIRTUAL: 1010 p->p_flags &= ~P_SIGVTALRM; 1011 break; 1012 case ITIMER_PROF: 1013 p->p_flags &= ~P_SIGPROF; 1014 break; 1015 } 1016 } 1017 lwkt_reltoken(&p->p_token); 1018 return (0); 1019 } 1020 1021 /* 1022 * Real interval timer expired: 1023 * send process whose timer expired an alarm signal. 1024 * If time is not set up to reload, then just return. 1025 * Else compute next time timer should go off which is > current time. 1026 * This is where delay in processing this timeout causes multiple 1027 * SIGALRM calls to be compressed into one. 1028 * tvtohz_high() always adds 1 to allow for the time until the next clock 1029 * interrupt being strictly less than 1 clock tick, but we don't want 1030 * that here since we want to appear to be in sync with the clock 1031 * interrupt even when we're delayed. 1032 */ 1033 static 1034 void 1035 realitexpire(void *arg) 1036 { 1037 struct proc *p; 1038 struct timeval ctv, ntv; 1039 1040 p = (struct proc *)arg; 1041 PHOLD(p); 1042 lwkt_gettoken(&p->p_token); 1043 ksignal(p, SIGALRM); 1044 if (!timevalisset(&p->p_realtimer.it_interval)) { 1045 timevalclear(&p->p_realtimer.it_value); 1046 goto done; 1047 } 1048 for (;;) { 1049 timevaladd(&p->p_realtimer.it_value, 1050 &p->p_realtimer.it_interval); 1051 getmicrouptime(&ctv); 1052 if (timevalcmp(&p->p_realtimer.it_value, &ctv, >)) { 1053 ntv = p->p_realtimer.it_value; 1054 timevalsub(&ntv, &ctv); 1055 callout_reset(&p->p_ithandle, tvtohz_low(&ntv), 1056 realitexpire, p); 1057 goto done; 1058 } 1059 } 1060 done: 1061 lwkt_reltoken(&p->p_token); 1062 PRELE(p); 1063 } 1064 1065 /* 1066 * Used to validate itimer timeouts and utimes*() timespecs. 1067 */ 1068 int 1069 itimerfix(struct timeval *tv) 1070 { 1071 if (tv->tv_sec < 0 || tv->tv_usec < 0 || tv->tv_usec >= 1000000) 1072 return (EINVAL); 1073 if (tv->tv_sec == 0 && tv->tv_usec != 0 && tv->tv_usec < ustick) 1074 tv->tv_usec = ustick; 1075 return (0); 1076 } 1077 1078 /* 1079 * Used to validate timeouts and utimes*() timespecs. 1080 */ 1081 int 1082 itimespecfix(struct timespec *ts) 1083 { 1084 if (ts->tv_sec < 0 || ts->tv_nsec < 0 || ts->tv_nsec >= 1000000000ULL) 1085 return (EINVAL); 1086 if (ts->tv_sec == 0 && ts->tv_nsec != 0 && ts->tv_nsec < nstick) 1087 ts->tv_nsec = nstick; 1088 return (0); 1089 } 1090 1091 /* 1092 * Decrement an interval timer by a specified number 1093 * of microseconds, which must be less than a second, 1094 * i.e. < 1000000. If the timer expires, then reload 1095 * it. In this case, carry over (usec - old value) to 1096 * reduce the value reloaded into the timer so that 1097 * the timer does not drift. This routine assumes 1098 * that it is called in a context where the timers 1099 * on which it is operating cannot change in value. 1100 */ 1101 int 1102 itimerdecr(struct itimerval *itp, int usec) 1103 { 1104 1105 if (itp->it_value.tv_usec < usec) { 1106 if (itp->it_value.tv_sec == 0) { 1107 /* expired, and already in next interval */ 1108 usec -= itp->it_value.tv_usec; 1109 goto expire; 1110 } 1111 itp->it_value.tv_usec += 1000000; 1112 itp->it_value.tv_sec--; 1113 } 1114 itp->it_value.tv_usec -= usec; 1115 usec = 0; 1116 if (timevalisset(&itp->it_value)) 1117 return (1); 1118 /* expired, exactly at end of interval */ 1119 expire: 1120 if (timevalisset(&itp->it_interval)) { 1121 itp->it_value = itp->it_interval; 1122 itp->it_value.tv_usec -= usec; 1123 if (itp->it_value.tv_usec < 0) { 1124 itp->it_value.tv_usec += 1000000; 1125 itp->it_value.tv_sec--; 1126 } 1127 } else 1128 itp->it_value.tv_usec = 0; /* sec is already 0 */ 1129 return (0); 1130 } 1131 1132 /* 1133 * Add and subtract routines for timevals. 1134 * N.B.: subtract routine doesn't deal with 1135 * results which are before the beginning, 1136 * it just gets very confused in this case. 1137 * Caveat emptor. 1138 */ 1139 void 1140 timevaladd(struct timeval *t1, const struct timeval *t2) 1141 { 1142 1143 t1->tv_sec += t2->tv_sec; 1144 t1->tv_usec += t2->tv_usec; 1145 timevalfix(t1); 1146 } 1147 1148 void 1149 timevalsub(struct timeval *t1, const struct timeval *t2) 1150 { 1151 1152 t1->tv_sec -= t2->tv_sec; 1153 t1->tv_usec -= t2->tv_usec; 1154 timevalfix(t1); 1155 } 1156 1157 static void 1158 timevalfix(struct timeval *t1) 1159 { 1160 1161 if (t1->tv_usec < 0) { 1162 t1->tv_sec--; 1163 t1->tv_usec += 1000000; 1164 } 1165 if (t1->tv_usec >= 1000000) { 1166 t1->tv_sec++; 1167 t1->tv_usec -= 1000000; 1168 } 1169 } 1170 1171 /* 1172 * ratecheck(): simple time-based rate-limit checking. 1173 */ 1174 int 1175 ratecheck(struct timeval *lasttime, const struct timeval *mininterval) 1176 { 1177 struct timeval tv, delta; 1178 int rv = 0; 1179 1180 getmicrouptime(&tv); /* NB: 10ms precision */ 1181 delta = tv; 1182 timevalsub(&delta, lasttime); 1183 1184 /* 1185 * check for 0,0 is so that the message will be seen at least once, 1186 * even if interval is huge. 1187 */ 1188 if (timevalcmp(&delta, mininterval, >=) || 1189 (lasttime->tv_sec == 0 && lasttime->tv_usec == 0)) { 1190 *lasttime = tv; 1191 rv = 1; 1192 } 1193 1194 return (rv); 1195 } 1196 1197 /* 1198 * ppsratecheck(): packets (or events) per second limitation. 1199 * 1200 * Return 0 if the limit is to be enforced (e.g. the caller 1201 * should drop a packet because of the rate limitation). 1202 * 1203 * maxpps of 0 always causes zero to be returned. maxpps of -1 1204 * always causes 1 to be returned; this effectively defeats rate 1205 * limiting. 1206 * 1207 * Note that we maintain the struct timeval for compatibility 1208 * with other bsd systems. We reuse the storage and just monitor 1209 * clock ticks for minimal overhead. 1210 */ 1211 int 1212 ppsratecheck(struct timeval *lasttime, int *curpps, int maxpps) 1213 { 1214 int now; 1215 1216 /* 1217 * Reset the last time and counter if this is the first call 1218 * or more than a second has passed since the last update of 1219 * lasttime. 1220 */ 1221 now = ticks; 1222 if (lasttime->tv_sec == 0 || (u_int)(now - lasttime->tv_sec) >= hz) { 1223 lasttime->tv_sec = now; 1224 *curpps = 1; 1225 return (maxpps != 0); 1226 } else { 1227 (*curpps)++; /* NB: ignore potential overflow */ 1228 return (maxpps < 0 || *curpps < maxpps); 1229 } 1230 } 1231 1232 static int 1233 sysctl_gettimeofday_quick(SYSCTL_HANDLER_ARGS) 1234 { 1235 int error; 1236 int gtod; 1237 1238 gtod = gettimeofday_quick; 1239 error = sysctl_handle_int(oidp, >od, 0, req); 1240 if (error || req->newptr == NULL) 1241 return error; 1242 gettimeofday_quick = gtod; 1243 if (kpmap) 1244 kpmap->fast_gtod = gtod; 1245 return 0; 1246 } 1247