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