1 /*- 2 * Copyright (c) 1982, 1986, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)kern_clock.c 8.5 (Berkeley) 1/21/94 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "opt_kdb.h" 41 #include "opt_device_polling.h" 42 #include "opt_hwpmc_hooks.h" 43 #include "opt_ntp.h" 44 #include "opt_watchdog.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/callout.h> 49 #include <sys/kdb.h> 50 #include <sys/kernel.h> 51 #include <sys/kthread.h> 52 #include <sys/ktr.h> 53 #include <sys/lock.h> 54 #include <sys/mutex.h> 55 #include <sys/proc.h> 56 #include <sys/resource.h> 57 #include <sys/resourcevar.h> 58 #include <sys/sched.h> 59 #include <sys/sdt.h> 60 #include <sys/signalvar.h> 61 #include <sys/sleepqueue.h> 62 #include <sys/smp.h> 63 #include <vm/vm.h> 64 #include <vm/pmap.h> 65 #include <vm/vm_map.h> 66 #include <sys/sysctl.h> 67 #include <sys/bus.h> 68 #include <sys/interrupt.h> 69 #include <sys/limits.h> 70 #include <sys/timetc.h> 71 72 #ifdef GPROF 73 #include <sys/gmon.h> 74 #endif 75 76 #ifdef HWPMC_HOOKS 77 #include <sys/pmckern.h> 78 PMC_SOFT_DEFINE( , , clock, hard); 79 PMC_SOFT_DEFINE( , , clock, stat); 80 PMC_SOFT_DEFINE_EX( , , clock, prof, \ 81 cpu_startprofclock, cpu_stopprofclock); 82 #endif 83 84 #ifdef DEVICE_POLLING 85 extern void hardclock_device_poll(void); 86 #endif /* DEVICE_POLLING */ 87 88 static void initclocks(void *dummy); 89 SYSINIT(clocks, SI_SUB_CLOCKS, SI_ORDER_FIRST, initclocks, NULL); 90 91 /* Spin-lock protecting profiling statistics. */ 92 static struct mtx time_lock; 93 94 SDT_PROVIDER_DECLARE(sched); 95 SDT_PROBE_DEFINE2(sched, , , tick, "struct thread *", "struct proc *"); 96 97 static int 98 sysctl_kern_cp_time(SYSCTL_HANDLER_ARGS) 99 { 100 int error; 101 long cp_time[CPUSTATES]; 102 #ifdef SCTL_MASK32 103 int i; 104 unsigned int cp_time32[CPUSTATES]; 105 #endif 106 107 read_cpu_time(cp_time); 108 #ifdef SCTL_MASK32 109 if (req->flags & SCTL_MASK32) { 110 if (!req->oldptr) 111 return SYSCTL_OUT(req, 0, sizeof(cp_time32)); 112 for (i = 0; i < CPUSTATES; i++) 113 cp_time32[i] = (unsigned int)cp_time[i]; 114 error = SYSCTL_OUT(req, cp_time32, sizeof(cp_time32)); 115 } else 116 #endif 117 { 118 if (!req->oldptr) 119 return SYSCTL_OUT(req, 0, sizeof(cp_time)); 120 error = SYSCTL_OUT(req, cp_time, sizeof(cp_time)); 121 } 122 return error; 123 } 124 125 SYSCTL_PROC(_kern, OID_AUTO, cp_time, CTLTYPE_LONG|CTLFLAG_RD|CTLFLAG_MPSAFE, 126 0,0, sysctl_kern_cp_time, "LU", "CPU time statistics"); 127 128 static long empty[CPUSTATES]; 129 130 static int 131 sysctl_kern_cp_times(SYSCTL_HANDLER_ARGS) 132 { 133 struct pcpu *pcpu; 134 int error; 135 int c; 136 long *cp_time; 137 #ifdef SCTL_MASK32 138 unsigned int cp_time32[CPUSTATES]; 139 int i; 140 #endif 141 142 if (!req->oldptr) { 143 #ifdef SCTL_MASK32 144 if (req->flags & SCTL_MASK32) 145 return SYSCTL_OUT(req, 0, sizeof(cp_time32) * (mp_maxid + 1)); 146 else 147 #endif 148 return SYSCTL_OUT(req, 0, sizeof(long) * CPUSTATES * (mp_maxid + 1)); 149 } 150 for (error = 0, c = 0; error == 0 && c <= mp_maxid; c++) { 151 if (!CPU_ABSENT(c)) { 152 pcpu = pcpu_find(c); 153 cp_time = pcpu->pc_cp_time; 154 } else { 155 cp_time = empty; 156 } 157 #ifdef SCTL_MASK32 158 if (req->flags & SCTL_MASK32) { 159 for (i = 0; i < CPUSTATES; i++) 160 cp_time32[i] = (unsigned int)cp_time[i]; 161 error = SYSCTL_OUT(req, cp_time32, sizeof(cp_time32)); 162 } else 163 #endif 164 error = SYSCTL_OUT(req, cp_time, sizeof(long) * CPUSTATES); 165 } 166 return error; 167 } 168 169 SYSCTL_PROC(_kern, OID_AUTO, cp_times, CTLTYPE_LONG|CTLFLAG_RD|CTLFLAG_MPSAFE, 170 0,0, sysctl_kern_cp_times, "LU", "per-CPU time statistics"); 171 172 #ifdef DEADLKRES 173 static const char *blessed[] = { 174 "getblk", 175 "so_snd_sx", 176 "so_rcv_sx", 177 NULL 178 }; 179 static int slptime_threshold = 1800; 180 static int blktime_threshold = 900; 181 static int sleepfreq = 3; 182 183 static void 184 deadlkres(void) 185 { 186 struct proc *p; 187 struct thread *td; 188 void *wchan; 189 int blkticks, i, slpticks, slptype, tryl, tticks; 190 191 tryl = 0; 192 for (;;) { 193 blkticks = blktime_threshold * hz; 194 slpticks = slptime_threshold * hz; 195 196 /* 197 * Avoid to sleep on the sx_lock in order to avoid a possible 198 * priority inversion problem leading to starvation. 199 * If the lock can't be held after 100 tries, panic. 200 */ 201 if (!sx_try_slock(&allproc_lock)) { 202 if (tryl > 100) 203 panic("%s: possible deadlock detected on allproc_lock\n", 204 __func__); 205 tryl++; 206 pause("allproc", sleepfreq * hz); 207 continue; 208 } 209 tryl = 0; 210 FOREACH_PROC_IN_SYSTEM(p) { 211 PROC_LOCK(p); 212 if (p->p_state == PRS_NEW) { 213 PROC_UNLOCK(p); 214 continue; 215 } 216 FOREACH_THREAD_IN_PROC(p, td) { 217 218 thread_lock(td); 219 if (TD_ON_LOCK(td)) { 220 221 /* 222 * The thread should be blocked on a 223 * turnstile, simply check if the 224 * turnstile channel is in good state. 225 */ 226 MPASS(td->td_blocked != NULL); 227 228 tticks = ticks - td->td_blktick; 229 thread_unlock(td); 230 if (tticks > blkticks) { 231 232 /* 233 * Accordingly with provided 234 * thresholds, this thread is 235 * stuck for too long on a 236 * turnstile. 237 */ 238 PROC_UNLOCK(p); 239 sx_sunlock(&allproc_lock); 240 panic("%s: possible deadlock detected for %p, blocked for %d ticks\n", 241 __func__, td, tticks); 242 } 243 } else if (TD_IS_SLEEPING(td) && 244 TD_ON_SLEEPQ(td)) { 245 246 /* 247 * Check if the thread is sleeping on a 248 * lock, otherwise skip the check. 249 * Drop the thread lock in order to 250 * avoid a LOR with the sleepqueue 251 * spinlock. 252 */ 253 wchan = td->td_wchan; 254 tticks = ticks - td->td_slptick; 255 thread_unlock(td); 256 slptype = sleepq_type(wchan); 257 if ((slptype == SLEEPQ_SX || 258 slptype == SLEEPQ_LK) && 259 tticks > slpticks) { 260 261 /* 262 * Accordingly with provided 263 * thresholds, this thread is 264 * stuck for too long on a 265 * sleepqueue. 266 * However, being on a 267 * sleepqueue, we might still 268 * check for the blessed 269 * list. 270 */ 271 tryl = 0; 272 for (i = 0; blessed[i] != NULL; 273 i++) { 274 if (!strcmp(blessed[i], 275 td->td_wmesg)) { 276 tryl = 1; 277 break; 278 } 279 } 280 if (tryl != 0) { 281 tryl = 0; 282 continue; 283 } 284 PROC_UNLOCK(p); 285 sx_sunlock(&allproc_lock); 286 panic("%s: possible deadlock detected for %p, blocked for %d ticks\n", 287 __func__, td, tticks); 288 } 289 } else 290 thread_unlock(td); 291 } 292 PROC_UNLOCK(p); 293 } 294 sx_sunlock(&allproc_lock); 295 296 /* Sleep for sleepfreq seconds. */ 297 pause("-", sleepfreq * hz); 298 } 299 } 300 301 static struct kthread_desc deadlkres_kd = { 302 "deadlkres", 303 deadlkres, 304 (struct thread **)NULL 305 }; 306 307 SYSINIT(deadlkres, SI_SUB_CLOCKS, SI_ORDER_ANY, kthread_start, &deadlkres_kd); 308 309 static SYSCTL_NODE(_debug, OID_AUTO, deadlkres, CTLFLAG_RW, 0, 310 "Deadlock resolver"); 311 SYSCTL_INT(_debug_deadlkres, OID_AUTO, slptime_threshold, CTLFLAG_RW, 312 &slptime_threshold, 0, 313 "Number of seconds within is valid to sleep on a sleepqueue"); 314 SYSCTL_INT(_debug_deadlkres, OID_AUTO, blktime_threshold, CTLFLAG_RW, 315 &blktime_threshold, 0, 316 "Number of seconds within is valid to block on a turnstile"); 317 SYSCTL_INT(_debug_deadlkres, OID_AUTO, sleepfreq, CTLFLAG_RW, &sleepfreq, 0, 318 "Number of seconds between any deadlock resolver thread run"); 319 #endif /* DEADLKRES */ 320 321 void 322 read_cpu_time(long *cp_time) 323 { 324 struct pcpu *pc; 325 int i, j; 326 327 /* Sum up global cp_time[]. */ 328 bzero(cp_time, sizeof(long) * CPUSTATES); 329 CPU_FOREACH(i) { 330 pc = pcpu_find(i); 331 for (j = 0; j < CPUSTATES; j++) 332 cp_time[j] += pc->pc_cp_time[j]; 333 } 334 } 335 336 #ifdef SW_WATCHDOG 337 #include <sys/watchdog.h> 338 339 static int watchdog_ticks; 340 static int watchdog_enabled; 341 static void watchdog_fire(void); 342 static void watchdog_config(void *, u_int, int *); 343 #endif /* SW_WATCHDOG */ 344 345 /* 346 * Clock handling routines. 347 * 348 * This code is written to operate with two timers that run independently of 349 * each other. 350 * 351 * The main timer, running hz times per second, is used to trigger interval 352 * timers, timeouts and rescheduling as needed. 353 * 354 * The second timer handles kernel and user profiling, 355 * and does resource use estimation. If the second timer is programmable, 356 * it is randomized to avoid aliasing between the two clocks. For example, 357 * the randomization prevents an adversary from always giving up the cpu 358 * just before its quantum expires. Otherwise, it would never accumulate 359 * cpu ticks. The mean frequency of the second timer is stathz. 360 * 361 * If no second timer exists, stathz will be zero; in this case we drive 362 * profiling and statistics off the main clock. This WILL NOT be accurate; 363 * do not do it unless absolutely necessary. 364 * 365 * The statistics clock may (or may not) be run at a higher rate while 366 * profiling. This profile clock runs at profhz. We require that profhz 367 * be an integral multiple of stathz. 368 * 369 * If the statistics clock is running fast, it must be divided by the ratio 370 * profhz/stathz for statistics. (For profiling, every tick counts.) 371 * 372 * Time-of-day is maintained using a "timecounter", which may or may 373 * not be related to the hardware generating the above mentioned 374 * interrupts. 375 */ 376 377 int stathz; 378 int profhz; 379 int profprocs; 380 volatile int ticks; 381 int psratio; 382 383 static DPCPU_DEFINE(int, pcputicks); /* Per-CPU version of ticks. */ 384 #ifdef DEVICE_POLLING 385 static int devpoll_run = 0; 386 #endif 387 388 /* 389 * Initialize clock frequencies and start both clocks running. 390 */ 391 /* ARGSUSED*/ 392 static void 393 initclocks(void *dummy) 394 { 395 int i; 396 397 /* 398 * Set divisors to 1 (normal case) and let the machine-specific 399 * code do its bit. 400 */ 401 mtx_init(&time_lock, "time lock", NULL, MTX_DEF); 402 cpu_initclocks(); 403 404 /* 405 * Compute profhz/stathz, and fix profhz if needed. 406 */ 407 i = stathz ? stathz : hz; 408 if (profhz == 0) 409 profhz = i; 410 psratio = profhz / i; 411 #ifdef SW_WATCHDOG 412 EVENTHANDLER_REGISTER(watchdog_list, watchdog_config, NULL, 0); 413 #endif 414 } 415 416 /* 417 * Each time the real-time timer fires, this function is called on all CPUs. 418 * Note that hardclock() calls hardclock_cpu() for the boot CPU, so only 419 * the other CPUs in the system need to call this function. 420 */ 421 void 422 hardclock_cpu(int usermode) 423 { 424 struct pstats *pstats; 425 struct thread *td = curthread; 426 struct proc *p = td->td_proc; 427 int flags; 428 429 /* 430 * Run current process's virtual and profile time, as needed. 431 */ 432 pstats = p->p_stats; 433 flags = 0; 434 if (usermode && 435 timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value)) { 436 PROC_ITIMLOCK(p); 437 if (itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], tick) == 0) 438 flags |= TDF_ALRMPEND | TDF_ASTPENDING; 439 PROC_ITIMUNLOCK(p); 440 } 441 if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value)) { 442 PROC_ITIMLOCK(p); 443 if (itimerdecr(&pstats->p_timer[ITIMER_PROF], tick) == 0) 444 flags |= TDF_PROFPEND | TDF_ASTPENDING; 445 PROC_ITIMUNLOCK(p); 446 } 447 thread_lock(td); 448 td->td_flags |= flags; 449 thread_unlock(td); 450 451 #ifdef HWPMC_HOOKS 452 if (PMC_CPU_HAS_SAMPLES(PCPU_GET(cpuid))) 453 PMC_CALL_HOOK_UNLOCKED(curthread, PMC_FN_DO_SAMPLES, NULL); 454 if (td->td_intr_frame != NULL) 455 PMC_SOFT_CALL_TF( , , clock, hard, td->td_intr_frame); 456 #endif 457 callout_process(sbinuptime()); 458 } 459 460 /* 461 * The real-time timer, interrupting hz times per second. 462 */ 463 void 464 hardclock(int usermode, uintfptr_t pc) 465 { 466 467 atomic_add_int(&ticks, 1); 468 hardclock_cpu(usermode); 469 tc_ticktock(1); 470 cpu_tick_calibration(); 471 /* 472 * If no separate statistics clock is available, run it from here. 473 * 474 * XXX: this only works for UP 475 */ 476 if (stathz == 0) { 477 profclock(usermode, pc); 478 statclock(usermode); 479 } 480 #ifdef DEVICE_POLLING 481 hardclock_device_poll(); /* this is very short and quick */ 482 #endif /* DEVICE_POLLING */ 483 #ifdef SW_WATCHDOG 484 if (watchdog_enabled > 0 && --watchdog_ticks <= 0) 485 watchdog_fire(); 486 #endif /* SW_WATCHDOG */ 487 } 488 489 void 490 hardclock_cnt(int cnt, int usermode) 491 { 492 struct pstats *pstats; 493 struct thread *td = curthread; 494 struct proc *p = td->td_proc; 495 int *t = DPCPU_PTR(pcputicks); 496 int flags, global, newticks; 497 #ifdef SW_WATCHDOG 498 int i; 499 #endif /* SW_WATCHDOG */ 500 501 /* 502 * Update per-CPU and possibly global ticks values. 503 */ 504 *t += cnt; 505 do { 506 global = ticks; 507 newticks = *t - global; 508 if (newticks <= 0) { 509 if (newticks < -1) 510 *t = global - 1; 511 newticks = 0; 512 break; 513 } 514 } while (!atomic_cmpset_int(&ticks, global, *t)); 515 516 /* 517 * Run current process's virtual and profile time, as needed. 518 */ 519 pstats = p->p_stats; 520 flags = 0; 521 if (usermode && 522 timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value)) { 523 PROC_ITIMLOCK(p); 524 if (itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], 525 tick * cnt) == 0) 526 flags |= TDF_ALRMPEND | TDF_ASTPENDING; 527 PROC_ITIMUNLOCK(p); 528 } 529 if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value)) { 530 PROC_ITIMLOCK(p); 531 if (itimerdecr(&pstats->p_timer[ITIMER_PROF], 532 tick * cnt) == 0) 533 flags |= TDF_PROFPEND | TDF_ASTPENDING; 534 PROC_ITIMUNLOCK(p); 535 } 536 if (flags != 0) { 537 thread_lock(td); 538 td->td_flags |= flags; 539 thread_unlock(td); 540 } 541 542 #ifdef HWPMC_HOOKS 543 if (PMC_CPU_HAS_SAMPLES(PCPU_GET(cpuid))) 544 PMC_CALL_HOOK_UNLOCKED(curthread, PMC_FN_DO_SAMPLES, NULL); 545 if (td->td_intr_frame != NULL) 546 PMC_SOFT_CALL_TF( , , clock, hard, td->td_intr_frame); 547 #endif 548 /* We are in charge to handle this tick duty. */ 549 if (newticks > 0) { 550 tc_ticktock(newticks); 551 #ifdef DEVICE_POLLING 552 /* Dangerous and no need to call these things concurrently. */ 553 if (atomic_cmpset_acq_int(&devpoll_run, 0, 1)) { 554 /* This is very short and quick. */ 555 hardclock_device_poll(); 556 atomic_store_rel_int(&devpoll_run, 0); 557 } 558 #endif /* DEVICE_POLLING */ 559 #ifdef SW_WATCHDOG 560 if (watchdog_enabled > 0) { 561 i = atomic_fetchadd_int(&watchdog_ticks, -newticks); 562 if (i > 0 && i <= newticks) 563 watchdog_fire(); 564 } 565 #endif /* SW_WATCHDOG */ 566 } 567 if (curcpu == CPU_FIRST()) 568 cpu_tick_calibration(); 569 } 570 571 void 572 hardclock_sync(int cpu) 573 { 574 int *t = DPCPU_ID_PTR(cpu, pcputicks); 575 576 *t = ticks; 577 } 578 579 /* 580 * Compute number of ticks in the specified amount of time. 581 */ 582 int 583 tvtohz(struct timeval *tv) 584 { 585 unsigned long ticks; 586 long sec, usec; 587 588 /* 589 * If the number of usecs in the whole seconds part of the time 590 * difference fits in a long, then the total number of usecs will 591 * fit in an unsigned long. Compute the total and convert it to 592 * ticks, rounding up and adding 1 to allow for the current tick 593 * to expire. Rounding also depends on unsigned long arithmetic 594 * to avoid overflow. 595 * 596 * Otherwise, if the number of ticks in the whole seconds part of 597 * the time difference fits in a long, then convert the parts to 598 * ticks separately and add, using similar rounding methods and 599 * overflow avoidance. This method would work in the previous 600 * case but it is slightly slower and assumes that hz is integral. 601 * 602 * Otherwise, round the time difference down to the maximum 603 * representable value. 604 * 605 * If ints have 32 bits, then the maximum value for any timeout in 606 * 10ms ticks is 248 days. 607 */ 608 sec = tv->tv_sec; 609 usec = tv->tv_usec; 610 if (usec < 0) { 611 sec--; 612 usec += 1000000; 613 } 614 if (sec < 0) { 615 #ifdef DIAGNOSTIC 616 if (usec > 0) { 617 sec++; 618 usec -= 1000000; 619 } 620 printf("tvotohz: negative time difference %ld sec %ld usec\n", 621 sec, usec); 622 #endif 623 ticks = 1; 624 } else if (sec <= LONG_MAX / 1000000) 625 ticks = howmany(sec * 1000000 + (unsigned long)usec, tick) + 1; 626 else if (sec <= LONG_MAX / hz) 627 ticks = sec * hz 628 + howmany((unsigned long)usec, tick) + 1; 629 else 630 ticks = LONG_MAX; 631 if (ticks > INT_MAX) 632 ticks = INT_MAX; 633 return ((int)ticks); 634 } 635 636 /* 637 * Start profiling on a process. 638 * 639 * Kernel profiling passes proc0 which never exits and hence 640 * keeps the profile clock running constantly. 641 */ 642 void 643 startprofclock(struct proc *p) 644 { 645 646 PROC_LOCK_ASSERT(p, MA_OWNED); 647 if (p->p_flag & P_STOPPROF) 648 return; 649 if ((p->p_flag & P_PROFIL) == 0) { 650 p->p_flag |= P_PROFIL; 651 mtx_lock(&time_lock); 652 if (++profprocs == 1) 653 cpu_startprofclock(); 654 mtx_unlock(&time_lock); 655 } 656 } 657 658 /* 659 * Stop profiling on a process. 660 */ 661 void 662 stopprofclock(struct proc *p) 663 { 664 665 PROC_LOCK_ASSERT(p, MA_OWNED); 666 if (p->p_flag & P_PROFIL) { 667 if (p->p_profthreads != 0) { 668 while (p->p_profthreads != 0) { 669 p->p_flag |= P_STOPPROF; 670 msleep(&p->p_profthreads, &p->p_mtx, PPAUSE, 671 "stopprof", 0); 672 } 673 } 674 if ((p->p_flag & P_PROFIL) == 0) 675 return; 676 p->p_flag &= ~P_PROFIL; 677 mtx_lock(&time_lock); 678 if (--profprocs == 0) 679 cpu_stopprofclock(); 680 mtx_unlock(&time_lock); 681 } 682 } 683 684 /* 685 * Statistics clock. Updates rusage information and calls the scheduler 686 * to adjust priorities of the active thread. 687 * 688 * This should be called by all active processors. 689 */ 690 void 691 statclock(int usermode) 692 { 693 694 statclock_cnt(1, usermode); 695 } 696 697 void 698 statclock_cnt(int cnt, int usermode) 699 { 700 struct rusage *ru; 701 struct vmspace *vm; 702 struct thread *td; 703 struct proc *p; 704 long rss; 705 long *cp_time; 706 707 td = curthread; 708 p = td->td_proc; 709 710 cp_time = (long *)PCPU_PTR(cp_time); 711 if (usermode) { 712 /* 713 * Charge the time as appropriate. 714 */ 715 td->td_uticks += cnt; 716 if (p->p_nice > NZERO) 717 cp_time[CP_NICE] += cnt; 718 else 719 cp_time[CP_USER] += cnt; 720 } else { 721 /* 722 * Came from kernel mode, so we were: 723 * - handling an interrupt, 724 * - doing syscall or trap work on behalf of the current 725 * user process, or 726 * - spinning in the idle loop. 727 * Whichever it is, charge the time as appropriate. 728 * Note that we charge interrupts to the current process, 729 * regardless of whether they are ``for'' that process, 730 * so that we know how much of its real time was spent 731 * in ``non-process'' (i.e., interrupt) work. 732 */ 733 if ((td->td_pflags & TDP_ITHREAD) || 734 td->td_intr_nesting_level >= 2) { 735 td->td_iticks += cnt; 736 cp_time[CP_INTR] += cnt; 737 } else { 738 td->td_pticks += cnt; 739 td->td_sticks += cnt; 740 if (!TD_IS_IDLETHREAD(td)) 741 cp_time[CP_SYS] += cnt; 742 else 743 cp_time[CP_IDLE] += cnt; 744 } 745 } 746 747 /* Update resource usage integrals and maximums. */ 748 MPASS(p->p_vmspace != NULL); 749 vm = p->p_vmspace; 750 ru = &td->td_ru; 751 ru->ru_ixrss += pgtok(vm->vm_tsize) * cnt; 752 ru->ru_idrss += pgtok(vm->vm_dsize) * cnt; 753 ru->ru_isrss += pgtok(vm->vm_ssize) * cnt; 754 rss = pgtok(vmspace_resident_count(vm)); 755 if (ru->ru_maxrss < rss) 756 ru->ru_maxrss = rss; 757 KTR_POINT2(KTR_SCHED, "thread", sched_tdname(td), "statclock", 758 "prio:%d", td->td_priority, "stathz:%d", (stathz)?stathz:hz); 759 SDT_PROBE2(sched, , , tick, td, td->td_proc); 760 thread_lock_flags(td, MTX_QUIET); 761 for ( ; cnt > 0; cnt--) 762 sched_clock(td); 763 thread_unlock(td); 764 #ifdef HWPMC_HOOKS 765 if (td->td_intr_frame != NULL) 766 PMC_SOFT_CALL_TF( , , clock, stat, td->td_intr_frame); 767 #endif 768 } 769 770 void 771 profclock(int usermode, uintfptr_t pc) 772 { 773 774 profclock_cnt(1, usermode, pc); 775 } 776 777 void 778 profclock_cnt(int cnt, int usermode, uintfptr_t pc) 779 { 780 struct thread *td; 781 #ifdef GPROF 782 struct gmonparam *g; 783 uintfptr_t i; 784 #endif 785 786 td = curthread; 787 if (usermode) { 788 /* 789 * Came from user mode; CPU was in user state. 790 * If this process is being profiled, record the tick. 791 * if there is no related user location yet, don't 792 * bother trying to count it. 793 */ 794 if (td->td_proc->p_flag & P_PROFIL) 795 addupc_intr(td, pc, cnt); 796 } 797 #ifdef GPROF 798 else { 799 /* 800 * Kernel statistics are just like addupc_intr, only easier. 801 */ 802 g = &_gmonparam; 803 if (g->state == GMON_PROF_ON && pc >= g->lowpc) { 804 i = PC_TO_I(g, pc); 805 if (i < g->textsize) { 806 KCOUNT(g, i) += cnt; 807 } 808 } 809 } 810 #endif 811 #ifdef HWPMC_HOOKS 812 if (td->td_intr_frame != NULL) 813 PMC_SOFT_CALL_TF( , , clock, prof, td->td_intr_frame); 814 #endif 815 } 816 817 /* 818 * Return information about system clocks. 819 */ 820 static int 821 sysctl_kern_clockrate(SYSCTL_HANDLER_ARGS) 822 { 823 struct clockinfo clkinfo; 824 /* 825 * Construct clockinfo structure. 826 */ 827 bzero(&clkinfo, sizeof(clkinfo)); 828 clkinfo.hz = hz; 829 clkinfo.tick = tick; 830 clkinfo.profhz = profhz; 831 clkinfo.stathz = stathz ? stathz : hz; 832 return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req)); 833 } 834 835 SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, 836 CTLTYPE_STRUCT|CTLFLAG_RD|CTLFLAG_MPSAFE, 837 0, 0, sysctl_kern_clockrate, "S,clockinfo", 838 "Rate and period of various kernel clocks"); 839 840 #ifdef SW_WATCHDOG 841 842 static void 843 watchdog_config(void *unused __unused, u_int cmd, int *error) 844 { 845 u_int u; 846 847 u = cmd & WD_INTERVAL; 848 if (u >= WD_TO_1SEC) { 849 watchdog_ticks = (1 << (u - WD_TO_1SEC)) * hz; 850 watchdog_enabled = 1; 851 *error = 0; 852 } else { 853 watchdog_enabled = 0; 854 } 855 } 856 857 /* 858 * Handle a watchdog timeout by dumping interrupt information and 859 * then either dropping to DDB or panicking. 860 */ 861 static void 862 watchdog_fire(void) 863 { 864 int nintr; 865 uint64_t inttotal; 866 u_long *curintr; 867 char *curname; 868 869 curintr = intrcnt; 870 curname = intrnames; 871 inttotal = 0; 872 nintr = sintrcnt / sizeof(u_long); 873 874 printf("interrupt total\n"); 875 while (--nintr >= 0) { 876 if (*curintr) 877 printf("%-12s %20lu\n", curname, *curintr); 878 curname += strlen(curname) + 1; 879 inttotal += *curintr++; 880 } 881 printf("Total %20ju\n", (uintmax_t)inttotal); 882 883 #if defined(KDB) && !defined(KDB_UNATTENDED) 884 kdb_backtrace(); 885 kdb_enter(KDB_WHY_WATCHDOG, "watchdog timeout"); 886 #else 887 panic("watchdog timeout"); 888 #endif 889 } 890 891 #endif /* SW_WATCHDOG */ 892