1 /*- 2 * Copyright (c) 1997, 1998 Poul-Henning Kamp <phk@FreeBSD.org> 3 * Copyright (c) 1982, 1986, 1991, 1993 4 * The Regents of the University of California. All rights reserved. 5 * (c) UNIX System Laboratories, Inc. 6 * All or some portions of this file are derived from material licensed 7 * to the University of California by American Telephone and Telegraph 8 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 9 * the permission of UNIX System Laboratories, Inc. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * @(#)kern_clock.c 8.5 (Berkeley) 1/21/94 40 * $FreeBSD$ 41 */ 42 43 #include "opt_ntp.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/dkstat.h> 48 #include <sys/callout.h> 49 #include <sys/kernel.h> 50 #include <sys/proc.h> 51 #include <sys/malloc.h> 52 #include <sys/resourcevar.h> 53 #include <sys/signalvar.h> 54 #include <sys/timex.h> 55 #include <sys/timepps.h> 56 #include <vm/vm.h> 57 #include <sys/lock.h> 58 #include <vm/pmap.h> 59 #include <vm/vm_map.h> 60 #include <sys/sysctl.h> 61 62 #include <machine/cpu.h> 63 #include <machine/limits.h> 64 65 #ifdef GPROF 66 #include <sys/gmon.h> 67 #endif 68 69 #if defined(SMP) && defined(BETTER_CLOCK) 70 #include <machine/smp.h> 71 #endif 72 73 /* 74 * Number of timecounters used to implement stable storage 75 */ 76 #ifndef NTIMECOUNTER 77 #define NTIMECOUNTER 5 78 #endif 79 80 static MALLOC_DEFINE(M_TIMECOUNTER, "timecounter", 81 "Timecounter stable storage"); 82 83 static void initclocks __P((void *dummy)); 84 SYSINIT(clocks, SI_SUB_CLOCKS, SI_ORDER_FIRST, initclocks, NULL) 85 86 static void tco_forward __P((int force)); 87 static void tco_setscales __P((struct timecounter *tc)); 88 static __inline unsigned tco_delta __P((struct timecounter *tc)); 89 90 /* Some of these don't belong here, but it's easiest to concentrate them. */ 91 #if defined(SMP) && defined(BETTER_CLOCK) 92 long cp_time[CPUSTATES]; 93 #else 94 static long cp_time[CPUSTATES]; 95 #endif 96 97 long tk_cancc; 98 long tk_nin; 99 long tk_nout; 100 long tk_rawcc; 101 102 time_t time_second; 103 104 struct timeval boottime; 105 SYSCTL_STRUCT(_kern, KERN_BOOTTIME, boottime, CTLFLAG_RD, 106 &boottime, timeval, "System boottime"); 107 108 /* 109 * Which update policy to use. 110 * 0 - every tick, bad hardware may fail with "calcru negative..." 111 * 1 - more resistent to the above hardware, but less efficient. 112 */ 113 static int tco_method; 114 115 /* 116 * Implement a dummy timecounter which we can use until we get a real one 117 * in the air. This allows the console and other early stuff to use 118 * timeservices. 119 */ 120 121 static unsigned 122 dummy_get_timecount(struct timecounter *tc) 123 { 124 static unsigned now; 125 return (++now); 126 } 127 128 static struct timecounter dummy_timecounter = { 129 dummy_get_timecount, 130 0, 131 ~0u, 132 1000000, 133 "dummy" 134 }; 135 136 struct timecounter *timecounter = &dummy_timecounter; 137 138 /* 139 * Clock handling routines. 140 * 141 * This code is written to operate with two timers that run independently of 142 * each other. 143 * 144 * The main timer, running hz times per second, is used to trigger interval 145 * timers, timeouts and rescheduling as needed. 146 * 147 * The second timer handles kernel and user profiling, 148 * and does resource use estimation. If the second timer is programmable, 149 * it is randomized to avoid aliasing between the two clocks. For example, 150 * the randomization prevents an adversary from always giving up the cpu 151 * just before its quantum expires. Otherwise, it would never accumulate 152 * cpu ticks. The mean frequency of the second timer is stathz. 153 * 154 * If no second timer exists, stathz will be zero; in this case we drive 155 * profiling and statistics off the main clock. This WILL NOT be accurate; 156 * do not do it unless absolutely necessary. 157 * 158 * The statistics clock may (or may not) be run at a higher rate while 159 * profiling. This profile clock runs at profhz. We require that profhz 160 * be an integral multiple of stathz. 161 * 162 * If the statistics clock is running fast, it must be divided by the ratio 163 * profhz/stathz for statistics. (For profiling, every tick counts.) 164 * 165 * Time-of-day is maintained using a "timecounter", which may or may 166 * not be related to the hardware generating the above mentioned 167 * interrupts. 168 */ 169 170 int stathz; 171 int profhz; 172 static int profprocs; 173 int ticks; 174 static int psdiv, pscnt; /* prof => stat divider */ 175 int psratio; /* ratio: prof / stat */ 176 177 /* 178 * Initialize clock frequencies and start both clocks running. 179 */ 180 /* ARGSUSED*/ 181 static void 182 initclocks(dummy) 183 void *dummy; 184 { 185 register int i; 186 187 /* 188 * Set divisors to 1 (normal case) and let the machine-specific 189 * code do its bit. 190 */ 191 psdiv = pscnt = 1; 192 cpu_initclocks(); 193 194 /* 195 * Compute profhz/stathz, and fix profhz if needed. 196 */ 197 i = stathz ? stathz : hz; 198 if (profhz == 0) 199 profhz = i; 200 psratio = profhz / i; 201 } 202 203 /* 204 * The real-time timer, interrupting hz times per second. 205 */ 206 void 207 hardclock(frame) 208 register struct clockframe *frame; 209 { 210 register struct proc *p; 211 212 p = curproc; 213 if (p) { 214 register struct pstats *pstats; 215 216 /* 217 * Run current process's virtual and profile time, as needed. 218 */ 219 pstats = p->p_stats; 220 if (CLKF_USERMODE(frame) && 221 timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value) && 222 itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], tick) == 0) 223 psignal(p, SIGVTALRM); 224 if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value) && 225 itimerdecr(&pstats->p_timer[ITIMER_PROF], tick) == 0) 226 psignal(p, SIGPROF); 227 } 228 229 #if defined(SMP) && defined(BETTER_CLOCK) 230 forward_hardclock(pscnt); 231 #endif 232 233 /* 234 * If no separate statistics clock is available, run it from here. 235 */ 236 if (stathz == 0) 237 statclock(frame); 238 239 tco_forward(0); 240 ticks++; 241 242 /* 243 * Process callouts at a very low cpu priority, so we don't keep the 244 * relatively high clock interrupt priority any longer than necessary. 245 */ 246 if (TAILQ_FIRST(&callwheel[ticks & callwheelmask]) != NULL) { 247 if (CLKF_BASEPRI(frame)) { 248 /* 249 * Save the overhead of a software interrupt; 250 * it will happen as soon as we return, so do it now. 251 */ 252 (void)splsoftclock(); 253 softclock(); 254 } else 255 setsoftclock(); 256 } else if (softticks + 1 == ticks) 257 ++softticks; 258 } 259 260 /* 261 * Compute number of ticks in the specified amount of time. 262 */ 263 int 264 tvtohz(tv) 265 struct timeval *tv; 266 { 267 register unsigned long ticks; 268 register long sec, usec; 269 270 /* 271 * If the number of usecs in the whole seconds part of the time 272 * difference fits in a long, then the total number of usecs will 273 * fit in an unsigned long. Compute the total and convert it to 274 * ticks, rounding up and adding 1 to allow for the current tick 275 * to expire. Rounding also depends on unsigned long arithmetic 276 * to avoid overflow. 277 * 278 * Otherwise, if the number of ticks in the whole seconds part of 279 * the time difference fits in a long, then convert the parts to 280 * ticks separately and add, using similar rounding methods and 281 * overflow avoidance. This method would work in the previous 282 * case but it is slightly slower and assumes that hz is integral. 283 * 284 * Otherwise, round the time difference down to the maximum 285 * representable value. 286 * 287 * If ints have 32 bits, then the maximum value for any timeout in 288 * 10ms ticks is 248 days. 289 */ 290 sec = tv->tv_sec; 291 usec = tv->tv_usec; 292 if (usec < 0) { 293 sec--; 294 usec += 1000000; 295 } 296 if (sec < 0) { 297 #ifdef DIAGNOSTIC 298 if (usec > 0) { 299 sec++; 300 usec -= 1000000; 301 } 302 printf("tvotohz: negative time difference %ld sec %ld usec\n", 303 sec, usec); 304 #endif 305 ticks = 1; 306 } else if (sec <= LONG_MAX / 1000000) 307 ticks = (sec * 1000000 + (unsigned long)usec + (tick - 1)) 308 / tick + 1; 309 else if (sec <= LONG_MAX / hz) 310 ticks = sec * hz 311 + ((unsigned long)usec + (tick - 1)) / tick + 1; 312 else 313 ticks = LONG_MAX; 314 if (ticks > INT_MAX) 315 ticks = INT_MAX; 316 return ((int)ticks); 317 } 318 319 /* 320 * Start profiling on a process. 321 * 322 * Kernel profiling passes proc0 which never exits and hence 323 * keeps the profile clock running constantly. 324 */ 325 void 326 startprofclock(p) 327 register struct proc *p; 328 { 329 int s; 330 331 if ((p->p_flag & P_PROFIL) == 0) { 332 p->p_flag |= P_PROFIL; 333 if (++profprocs == 1 && stathz != 0) { 334 s = splstatclock(); 335 psdiv = pscnt = psratio; 336 setstatclockrate(profhz); 337 splx(s); 338 } 339 } 340 } 341 342 /* 343 * Stop profiling on a process. 344 */ 345 void 346 stopprofclock(p) 347 register struct proc *p; 348 { 349 int s; 350 351 if (p->p_flag & P_PROFIL) { 352 p->p_flag &= ~P_PROFIL; 353 if (--profprocs == 0 && stathz != 0) { 354 s = splstatclock(); 355 psdiv = pscnt = 1; 356 setstatclockrate(stathz); 357 splx(s); 358 } 359 } 360 } 361 362 /* 363 * Statistics clock. Grab profile sample, and if divider reaches 0, 364 * do process and kernel statistics. Most of the statistics are only 365 * used by user-level statistics programs. The main exceptions are 366 * p->p_uticks, p->p_sticks, p->p_iticks, and p->p_estcpu. 367 */ 368 void 369 statclock(frame) 370 register struct clockframe *frame; 371 { 372 #ifdef GPROF 373 register struct gmonparam *g; 374 int i; 375 #endif 376 register struct proc *p; 377 struct pstats *pstats; 378 long rss; 379 struct rusage *ru; 380 struct vmspace *vm; 381 382 if (curproc != NULL && CLKF_USERMODE(frame)) { 383 /* 384 * Came from user mode; CPU was in user state. 385 * If this process is being profiled, record the tick. 386 */ 387 p = curproc; 388 if (p->p_flag & P_PROFIL) 389 addupc_intr(p, CLKF_PC(frame), 1); 390 #if defined(SMP) && defined(BETTER_CLOCK) 391 if (stathz != 0) 392 forward_statclock(pscnt); 393 #endif 394 if (--pscnt > 0) 395 return; 396 /* 397 * Charge the time as appropriate. 398 */ 399 p->p_uticks++; 400 if (p->p_nice > NZERO) 401 cp_time[CP_NICE]++; 402 else 403 cp_time[CP_USER]++; 404 } else { 405 #ifdef GPROF 406 /* 407 * Kernel statistics are just like addupc_intr, only easier. 408 */ 409 g = &_gmonparam; 410 if (g->state == GMON_PROF_ON) { 411 i = CLKF_PC(frame) - g->lowpc; 412 if (i < g->textsize) { 413 i /= HISTFRACTION * sizeof(*g->kcount); 414 g->kcount[i]++; 415 } 416 } 417 #endif 418 #if defined(SMP) && defined(BETTER_CLOCK) 419 if (stathz != 0) 420 forward_statclock(pscnt); 421 #endif 422 if (--pscnt > 0) 423 return; 424 /* 425 * Came from kernel mode, so we were: 426 * - handling an interrupt, 427 * - doing syscall or trap work on behalf of the current 428 * user process, or 429 * - spinning in the idle loop. 430 * Whichever it is, charge the time as appropriate. 431 * Note that we charge interrupts to the current process, 432 * regardless of whether they are ``for'' that process, 433 * so that we know how much of its real time was spent 434 * in ``non-process'' (i.e., interrupt) work. 435 */ 436 p = curproc; 437 if (CLKF_INTR(frame)) { 438 if (p != NULL) 439 p->p_iticks++; 440 cp_time[CP_INTR]++; 441 } else if (p != NULL) { 442 p->p_sticks++; 443 cp_time[CP_SYS]++; 444 } else 445 cp_time[CP_IDLE]++; 446 } 447 pscnt = psdiv; 448 449 if (p != NULL) { 450 schedclock(p); 451 452 /* Update resource usage integrals and maximums. */ 453 if ((pstats = p->p_stats) != NULL && 454 (ru = &pstats->p_ru) != NULL && 455 (vm = p->p_vmspace) != NULL) { 456 ru->ru_ixrss += pgtok(vm->vm_tsize); 457 ru->ru_idrss += pgtok(vm->vm_dsize); 458 ru->ru_isrss += pgtok(vm->vm_ssize); 459 rss = pgtok(vmspace_resident_count(vm)); 460 if (ru->ru_maxrss < rss) 461 ru->ru_maxrss = rss; 462 } 463 } 464 } 465 466 /* 467 * Return information about system clocks. 468 */ 469 static int 470 sysctl_kern_clockrate SYSCTL_HANDLER_ARGS 471 { 472 struct clockinfo clkinfo; 473 /* 474 * Construct clockinfo structure. 475 */ 476 clkinfo.hz = hz; 477 clkinfo.tick = tick; 478 clkinfo.tickadj = tickadj; 479 clkinfo.profhz = profhz; 480 clkinfo.stathz = stathz ? stathz : hz; 481 return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req)); 482 } 483 484 SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, CTLTYPE_STRUCT|CTLFLAG_RD, 485 0, 0, sysctl_kern_clockrate, "S,clockinfo",""); 486 487 static __inline unsigned 488 tco_delta(struct timecounter *tc) 489 { 490 491 return ((tc->tc_get_timecount(tc) - tc->tc_offset_count) & 492 tc->tc_counter_mask); 493 } 494 495 /* 496 * We have eight functions for looking at the clock, four for 497 * microseconds and four for nanoseconds. For each there is fast 498 * but less precise version "get{nano|micro}[up]time" which will 499 * return a time which is up to 1/HZ previous to the call, whereas 500 * the raw version "{nano|micro}[up]time" will return a timestamp 501 * which is as precise as possible. The "up" variants return the 502 * time relative to system boot, these are well suited for time 503 * interval measurements. 504 */ 505 506 void 507 getmicrotime(struct timeval *tvp) 508 { 509 struct timecounter *tc; 510 511 if (!tco_method) { 512 tc = timecounter; 513 *tvp = tc->tc_microtime; 514 } else { 515 microtime(tvp); 516 } 517 } 518 519 void 520 getnanotime(struct timespec *tsp) 521 { 522 struct timecounter *tc; 523 524 if (!tco_method) { 525 tc = timecounter; 526 *tsp = tc->tc_nanotime; 527 } else { 528 nanotime(tsp); 529 } 530 } 531 532 void 533 microtime(struct timeval *tv) 534 { 535 struct timecounter *tc; 536 537 tc = timecounter; 538 tv->tv_sec = tc->tc_offset_sec; 539 tv->tv_usec = tc->tc_offset_micro; 540 tv->tv_usec += ((u_int64_t)tco_delta(tc) * tc->tc_scale_micro) >> 32; 541 tv->tv_usec += boottime.tv_usec; 542 tv->tv_sec += boottime.tv_sec; 543 while (tv->tv_usec >= 1000000) { 544 tv->tv_usec -= 1000000; 545 tv->tv_sec++; 546 } 547 } 548 549 void 550 nanotime(struct timespec *ts) 551 { 552 unsigned count; 553 u_int64_t delta; 554 struct timecounter *tc; 555 556 tc = timecounter; 557 ts->tv_sec = tc->tc_offset_sec; 558 count = tco_delta(tc); 559 delta = tc->tc_offset_nano; 560 delta += ((u_int64_t)count * tc->tc_scale_nano_f); 561 delta >>= 32; 562 delta += ((u_int64_t)count * tc->tc_scale_nano_i); 563 delta += boottime.tv_usec * 1000; 564 ts->tv_sec += boottime.tv_sec; 565 while (delta >= 1000000000) { 566 delta -= 1000000000; 567 ts->tv_sec++; 568 } 569 ts->tv_nsec = delta; 570 } 571 572 void 573 getmicrouptime(struct timeval *tvp) 574 { 575 struct timecounter *tc; 576 577 if (!tco_method) { 578 tc = timecounter; 579 tvp->tv_sec = tc->tc_offset_sec; 580 tvp->tv_usec = tc->tc_offset_micro; 581 } else { 582 microuptime(tvp); 583 } 584 } 585 586 void 587 getnanouptime(struct timespec *tsp) 588 { 589 struct timecounter *tc; 590 591 if (!tco_method) { 592 tc = timecounter; 593 tsp->tv_sec = tc->tc_offset_sec; 594 tsp->tv_nsec = tc->tc_offset_nano >> 32; 595 } else { 596 nanouptime(tsp); 597 } 598 } 599 600 void 601 microuptime(struct timeval *tv) 602 { 603 struct timecounter *tc; 604 605 tc = timecounter; 606 tv->tv_sec = tc->tc_offset_sec; 607 tv->tv_usec = tc->tc_offset_micro; 608 tv->tv_usec += ((u_int64_t)tco_delta(tc) * tc->tc_scale_micro) >> 32; 609 if (tv->tv_usec >= 1000000) { 610 tv->tv_usec -= 1000000; 611 tv->tv_sec++; 612 } 613 } 614 615 void 616 nanouptime(struct timespec *ts) 617 { 618 unsigned count; 619 u_int64_t delta; 620 struct timecounter *tc; 621 622 tc = timecounter; 623 ts->tv_sec = tc->tc_offset_sec; 624 count = tco_delta(tc); 625 delta = tc->tc_offset_nano; 626 delta += ((u_int64_t)count * tc->tc_scale_nano_f); 627 delta >>= 32; 628 delta += ((u_int64_t)count * tc->tc_scale_nano_i); 629 if (delta >= 1000000000) { 630 delta -= 1000000000; 631 ts->tv_sec++; 632 } 633 ts->tv_nsec = delta; 634 } 635 636 static void 637 tco_setscales(struct timecounter *tc) 638 { 639 u_int64_t scale; 640 641 scale = 1000000000LL << 32; 642 scale += tc->tc_adjustment; 643 scale /= tc->tc_tweak->tc_frequency; 644 tc->tc_scale_micro = scale / 1000; 645 tc->tc_scale_nano_f = scale & 0xffffffff; 646 tc->tc_scale_nano_i = scale >> 32; 647 } 648 649 void 650 update_timecounter(struct timecounter *tc) 651 { 652 tco_setscales(tc); 653 } 654 655 void 656 init_timecounter(struct timecounter *tc) 657 { 658 struct timespec ts1; 659 struct timecounter *t1, *t2, *t3; 660 int i; 661 662 tc->tc_adjustment = 0; 663 tc->tc_tweak = tc; 664 tco_setscales(tc); 665 tc->tc_offset_count = tc->tc_get_timecount(tc); 666 if (timecounter == &dummy_timecounter) 667 tc->tc_avail = tc; 668 else { 669 tc->tc_avail = timecounter->tc_tweak->tc_avail; 670 timecounter->tc_tweak->tc_avail = tc; 671 } 672 MALLOC(t1, struct timecounter *, sizeof *t1, M_TIMECOUNTER, M_WAITOK); 673 tc->tc_other = t1; 674 *t1 = *tc; 675 t2 = t1; 676 for (i = 1; i < NTIMECOUNTER; i++) { 677 MALLOC(t3, struct timecounter *, sizeof *t3, 678 M_TIMECOUNTER, M_WAITOK); 679 *t3 = *tc; 680 t3->tc_other = t2; 681 t2 = t3; 682 } 683 t1->tc_other = t3; 684 tc = t1; 685 686 printf("Timecounter \"%s\" frequency %lu Hz\n", 687 tc->tc_name, (u_long)tc->tc_frequency); 688 689 /* XXX: For now always start using the counter. */ 690 tc->tc_offset_count = tc->tc_get_timecount(tc); 691 nanouptime(&ts1); 692 tc->tc_offset_nano = (u_int64_t)ts1.tv_nsec << 32; 693 tc->tc_offset_micro = ts1.tv_nsec / 1000; 694 tc->tc_offset_sec = ts1.tv_sec; 695 timecounter = tc; 696 } 697 698 void 699 set_timecounter(struct timespec *ts) 700 { 701 struct timespec ts2; 702 703 nanouptime(&ts2); 704 boottime.tv_sec = ts->tv_sec - ts2.tv_sec; 705 boottime.tv_usec = (ts->tv_nsec - ts2.tv_nsec) / 1000; 706 if (boottime.tv_usec < 0) { 707 boottime.tv_usec += 1000000; 708 boottime.tv_sec--; 709 } 710 /* fiddle all the little crinkly bits around the fiords... */ 711 tco_forward(1); 712 } 713 714 static void 715 switch_timecounter(struct timecounter *newtc) 716 { 717 int s; 718 struct timecounter *tc; 719 struct timespec ts; 720 721 s = splclock(); 722 tc = timecounter; 723 if (newtc->tc_tweak == tc->tc_tweak) { 724 splx(s); 725 return; 726 } 727 newtc = newtc->tc_tweak->tc_other; 728 nanouptime(&ts); 729 newtc->tc_offset_sec = ts.tv_sec; 730 newtc->tc_offset_nano = (u_int64_t)ts.tv_nsec << 32; 731 newtc->tc_offset_micro = ts.tv_nsec / 1000; 732 newtc->tc_offset_count = newtc->tc_get_timecount(newtc); 733 tco_setscales(newtc); 734 timecounter = newtc; 735 splx(s); 736 } 737 738 static struct timecounter * 739 sync_other_counter(void) 740 { 741 struct timecounter *tc, *tcn, *tco; 742 unsigned delta; 743 744 tco = timecounter; 745 tc = tco->tc_other; 746 tcn = tc->tc_other; 747 *tc = *tco; 748 tc->tc_other = tcn; 749 delta = tco_delta(tc); 750 tc->tc_offset_count += delta; 751 tc->tc_offset_count &= tc->tc_counter_mask; 752 tc->tc_offset_nano += (u_int64_t)delta * tc->tc_scale_nano_f; 753 tc->tc_offset_nano += (u_int64_t)delta * tc->tc_scale_nano_i << 32; 754 return (tc); 755 } 756 757 static void 758 tco_forward(int force) 759 { 760 struct timecounter *tc, *tco; 761 struct timeval tvt; 762 763 tco = timecounter; 764 tc = sync_other_counter(); 765 /* 766 * We may be inducing a tiny error here, the tc_poll_pps() may 767 * process a latched count which happens after the tco_delta() 768 * in sync_other_counter(), which would extend the previous 769 * counters parameters into the domain of this new one. 770 * Since the timewindow is very small for this, the error is 771 * going to be only a few weenieseconds (as Dave Mills would 772 * say), so lets just not talk more about it, OK ? 773 */ 774 if (tco->tc_poll_pps) 775 tco->tc_poll_pps(tco); 776 if (timedelta != 0) { 777 tvt = boottime; 778 tvt.tv_usec -= tickdelta; 779 if (tvt.tv_usec >= 1000000) { 780 tvt.tv_sec++; 781 tvt.tv_usec -= 1000000; 782 } else if (tvt.tv_usec < 0) { 783 tvt.tv_sec--; 784 tvt.tv_usec += 1000000; 785 } 786 boottime = tvt; 787 timedelta -= tickdelta; 788 } 789 790 while (tc->tc_offset_nano >= 1000000000ULL << 32) { 791 tc->tc_offset_nano -= 1000000000ULL << 32; 792 tc->tc_offset_sec++; 793 ntp_update_second(tc); /* XXX only needed if xntpd runs */ 794 tco_setscales(tc); 795 force++; 796 } 797 798 if (tco_method && !force) 799 return; 800 801 tc->tc_offset_micro = (tc->tc_offset_nano / 1000) >> 32; 802 803 /* Figure out the wall-clock time */ 804 tc->tc_nanotime.tv_sec = tc->tc_offset_sec + boottime.tv_sec; 805 tc->tc_nanotime.tv_nsec = 806 (tc->tc_offset_nano >> 32) + boottime.tv_usec * 1000; 807 tc->tc_microtime.tv_usec = tc->tc_offset_micro + boottime.tv_usec; 808 if (tc->tc_nanotime.tv_nsec >= 1000000000) { 809 tc->tc_nanotime.tv_nsec -= 1000000000; 810 tc->tc_microtime.tv_usec -= 1000000; 811 tc->tc_nanotime.tv_sec++; 812 } 813 time_second = tc->tc_microtime.tv_sec = tc->tc_nanotime.tv_sec; 814 815 timecounter = tc; 816 } 817 818 SYSCTL_NODE(_kern, OID_AUTO, timecounter, CTLFLAG_RW, 0, ""); 819 820 SYSCTL_INT(_kern_timecounter, OID_AUTO, method, CTLFLAG_RW, &tco_method, 0, 821 "This variable determines the method used for updating timecounters. " 822 "If the default algorithm (0) fails with \"calcru negative...\" messages " 823 "try the alternate algorithm (1) which handles bad hardware better." 824 825 ); 826 827 static int 828 sysctl_kern_timecounter_hardware SYSCTL_HANDLER_ARGS 829 { 830 char newname[32]; 831 struct timecounter *newtc, *tc; 832 int error; 833 834 tc = timecounter->tc_tweak; 835 strncpy(newname, tc->tc_name, sizeof(newname)); 836 error = sysctl_handle_string(oidp, &newname[0], sizeof(newname), req); 837 if (error == 0 && req->newptr != NULL && 838 strcmp(newname, tc->tc_name) != 0) { 839 for (newtc = tc->tc_avail; newtc != tc; 840 newtc = newtc->tc_avail) { 841 if (strcmp(newname, newtc->tc_name) == 0) { 842 /* Warm up new timecounter. */ 843 (void)newtc->tc_get_timecount(newtc); 844 845 switch_timecounter(newtc); 846 return (0); 847 } 848 } 849 return (EINVAL); 850 } 851 return (error); 852 } 853 854 SYSCTL_PROC(_kern_timecounter, OID_AUTO, hardware, CTLTYPE_STRING | CTLFLAG_RW, 855 0, 0, sysctl_kern_timecounter_hardware, "A", ""); 856 857 858 int 859 pps_ioctl(u_long cmd, caddr_t data, struct pps_state *pps) 860 { 861 pps_params_t *app; 862 struct pps_fetch_args *fapi; 863 #ifdef PPS_SYNC 864 struct pps_kcbind_args *kapi; 865 #endif 866 867 switch (cmd) { 868 case PPS_IOC_CREATE: 869 return (0); 870 case PPS_IOC_DESTROY: 871 return (0); 872 case PPS_IOC_SETPARAMS: 873 app = (pps_params_t *)data; 874 if (app->mode & ~pps->ppscap) 875 return (EINVAL); 876 pps->ppsparam = *app; 877 return (0); 878 case PPS_IOC_GETPARAMS: 879 app = (pps_params_t *)data; 880 *app = pps->ppsparam; 881 app->api_version = PPS_API_VERS_1; 882 return (0); 883 case PPS_IOC_GETCAP: 884 *(int*)data = pps->ppscap; 885 return (0); 886 case PPS_IOC_FETCH: 887 fapi = (struct pps_fetch_args *)data; 888 if (fapi->tsformat && fapi->tsformat != PPS_TSFMT_TSPEC) 889 return (EINVAL); 890 if (fapi->timeout.tv_sec || fapi->timeout.tv_nsec) 891 return (EOPNOTSUPP); 892 pps->ppsinfo.current_mode = pps->ppsparam.mode; 893 fapi->pps_info_buf = pps->ppsinfo; 894 return (0); 895 case PPS_IOC_KCBIND: 896 #ifdef PPS_SYNC 897 kapi = (struct pps_kcbind_args *)data; 898 /* XXX Only root should be able to do this */ 899 if (kapi->tsformat && kapi->tsformat != PPS_TSFMT_TSPEC) 900 return (EINVAL); 901 if (kapi->kernel_consumer != PPS_KC_HARDPPS) 902 return (EINVAL); 903 if (kapi->edge & ~pps->ppscap) 904 return (EINVAL); 905 pps->kcmode = kapi->edge; 906 return (0); 907 #else 908 return (EOPNOTSUPP); 909 #endif 910 default: 911 return (ENOTTY); 912 } 913 } 914 915 void 916 pps_init(struct pps_state *pps) 917 { 918 pps->ppscap |= PPS_TSFMT_TSPEC; 919 if (pps->ppscap & PPS_CAPTUREASSERT) 920 pps->ppscap |= PPS_OFFSETASSERT; 921 if (pps->ppscap & PPS_CAPTURECLEAR) 922 pps->ppscap |= PPS_OFFSETCLEAR; 923 } 924 925 void 926 pps_event(struct pps_state *pps, struct timecounter *tc, unsigned count, int event) 927 { 928 struct timespec ts, *tsp, *osp; 929 u_int64_t delta; 930 unsigned tcount, *pcount; 931 int foff, fhard; 932 pps_seq_t *pseq; 933 934 /* Things would be easier with arrays... */ 935 if (event == PPS_CAPTUREASSERT) { 936 tsp = &pps->ppsinfo.assert_timestamp; 937 osp = &pps->ppsparam.assert_offset; 938 foff = pps->ppsparam.mode & PPS_OFFSETASSERT; 939 fhard = pps->kcmode & PPS_CAPTUREASSERT; 940 pcount = &pps->ppscount[0]; 941 pseq = &pps->ppsinfo.assert_sequence; 942 } else { 943 tsp = &pps->ppsinfo.clear_timestamp; 944 osp = &pps->ppsparam.clear_offset; 945 foff = pps->ppsparam.mode & PPS_OFFSETCLEAR; 946 fhard = pps->kcmode & PPS_CAPTURECLEAR; 947 pcount = &pps->ppscount[1]; 948 pseq = &pps->ppsinfo.clear_sequence; 949 } 950 951 /* The timecounter changed: bail */ 952 if (!pps->ppstc || 953 pps->ppstc->tc_name != tc->tc_name || 954 tc->tc_name != timecounter->tc_name) { 955 pps->ppstc = tc; 956 *pcount = count; 957 return; 958 } 959 960 /* Nothing really happened */ 961 if (*pcount == count) 962 return; 963 964 *pcount = count; 965 966 /* Convert the count to timespec */ 967 ts.tv_sec = tc->tc_offset_sec; 968 tcount = count - tc->tc_offset_count; 969 tcount &= tc->tc_counter_mask; 970 delta = tc->tc_offset_nano; 971 delta += ((u_int64_t)tcount * tc->tc_scale_nano_f); 972 delta >>= 32; 973 delta += ((u_int64_t)tcount * tc->tc_scale_nano_i); 974 delta += boottime.tv_usec * 1000; 975 ts.tv_sec += boottime.tv_sec; 976 while (delta >= 1000000000) { 977 delta -= 1000000000; 978 ts.tv_sec++; 979 } 980 ts.tv_nsec = delta; 981 982 (*pseq)++; 983 *tsp = ts; 984 985 if (foff) { 986 timespecadd(tsp, osp); 987 if (tsp->tv_nsec < 0) { 988 tsp->tv_nsec += 1000000000; 989 tsp->tv_sec -= 1; 990 } 991 } 992 #ifdef PPS_SYNC 993 if (fhard) { 994 /* magic, at its best... */ 995 tcount = count - pps->ppscount[2]; 996 pps->ppscount[2] = count; 997 tcount &= tc->tc_counter_mask; 998 delta = ((u_int64_t)tcount * tc->tc_tweak->tc_scale_nano_f); 999 delta >>= 32; 1000 delta += ((u_int64_t)tcount * tc->tc_tweak->tc_scale_nano_i); 1001 hardpps(tsp, delta); 1002 } 1003 #endif 1004 } 1005