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 * 4. 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 static int global_hardclock_run = 0; 385 386 /* 387 * Initialize clock frequencies and start both clocks running. 388 */ 389 /* ARGSUSED*/ 390 static void 391 initclocks(dummy) 392 void *dummy; 393 { 394 register int i; 395 396 /* 397 * Set divisors to 1 (normal case) and let the machine-specific 398 * code do its bit. 399 */ 400 mtx_init(&time_lock, "time lock", NULL, MTX_DEF); 401 cpu_initclocks(); 402 403 /* 404 * Compute profhz/stathz, and fix profhz if needed. 405 */ 406 i = stathz ? stathz : hz; 407 if (profhz == 0) 408 profhz = i; 409 psratio = profhz / i; 410 #ifdef SW_WATCHDOG 411 EVENTHANDLER_REGISTER(watchdog_list, watchdog_config, NULL, 0); 412 #endif 413 } 414 415 /* 416 * Each time the real-time timer fires, this function is called on all CPUs. 417 * Note that hardclock() calls hardclock_cpu() for the boot CPU, so only 418 * the other CPUs in the system need to call this function. 419 */ 420 void 421 hardclock_cpu(int usermode) 422 { 423 struct pstats *pstats; 424 struct thread *td = curthread; 425 struct proc *p = td->td_proc; 426 int flags; 427 428 /* 429 * Run current process's virtual and profile time, as needed. 430 */ 431 pstats = p->p_stats; 432 flags = 0; 433 if (usermode && 434 timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value)) { 435 PROC_SLOCK(p); 436 if (itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], tick) == 0) 437 flags |= TDF_ALRMPEND | TDF_ASTPENDING; 438 PROC_SUNLOCK(p); 439 } 440 if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value)) { 441 PROC_SLOCK(p); 442 if (itimerdecr(&pstats->p_timer[ITIMER_PROF], tick) == 0) 443 flags |= TDF_PROFPEND | TDF_ASTPENDING; 444 PROC_SUNLOCK(p); 445 } 446 thread_lock(td); 447 sched_tick(1); 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_SLOCK(p); 524 if (itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], 525 tick * cnt) == 0) 526 flags |= TDF_ALRMPEND | TDF_ASTPENDING; 527 PROC_SUNLOCK(p); 528 } 529 if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value)) { 530 PROC_SLOCK(p); 531 if (itimerdecr(&pstats->p_timer[ITIMER_PROF], 532 tick * cnt) == 0) 533 flags |= TDF_PROFPEND | TDF_ASTPENDING; 534 PROC_SUNLOCK(p); 535 } 536 thread_lock(td); 537 sched_tick(cnt); 538 td->td_flags |= flags; 539 thread_unlock(td); 540 541 #ifdef HWPMC_HOOKS 542 if (PMC_CPU_HAS_SAMPLES(PCPU_GET(cpuid))) 543 PMC_CALL_HOOK_UNLOCKED(curthread, PMC_FN_DO_SAMPLES, NULL); 544 if (td->td_intr_frame != NULL) 545 PMC_SOFT_CALL_TF( , , clock, hard, td->td_intr_frame); 546 #endif 547 /* We are in charge to handle this tick duty. */ 548 if (newticks > 0) { 549 /* Dangerous and no need to call these things concurrently. */ 550 if (atomic_cmpset_acq_int(&global_hardclock_run, 0, 1)) { 551 tc_ticktock(newticks); 552 #ifdef DEVICE_POLLING 553 /* This is very short and quick. */ 554 hardclock_device_poll(); 555 #endif /* DEVICE_POLLING */ 556 atomic_store_rel_int(&global_hardclock_run, 0); 557 } 558 #ifdef SW_WATCHDOG 559 if (watchdog_enabled > 0) { 560 i = atomic_fetchadd_int(&watchdog_ticks, -newticks); 561 if (i > 0 && i <= newticks) 562 watchdog_fire(); 563 } 564 #endif /* SW_WATCHDOG */ 565 } 566 if (curcpu == CPU_FIRST()) 567 cpu_tick_calibration(); 568 } 569 570 void 571 hardclock_sync(int cpu) 572 { 573 int *t = DPCPU_ID_PTR(cpu, pcputicks); 574 575 *t = ticks; 576 } 577 578 /* 579 * Compute number of ticks in the specified amount of time. 580 */ 581 int 582 tvtohz(tv) 583 struct timeval *tv; 584 { 585 register unsigned long ticks; 586 register 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 = (sec * 1000000 + (unsigned long)usec + (tick - 1)) 626 / tick + 1; 627 else if (sec <= LONG_MAX / hz) 628 ticks = sec * hz 629 + ((unsigned long)usec + (tick - 1)) / tick + 1; 630 else 631 ticks = LONG_MAX; 632 if (ticks > INT_MAX) 633 ticks = INT_MAX; 634 return ((int)ticks); 635 } 636 637 /* 638 * Start profiling on a process. 639 * 640 * Kernel profiling passes proc0 which never exits and hence 641 * keeps the profile clock running constantly. 642 */ 643 void 644 startprofclock(p) 645 register struct proc *p; 646 { 647 648 PROC_LOCK_ASSERT(p, MA_OWNED); 649 if (p->p_flag & P_STOPPROF) 650 return; 651 if ((p->p_flag & P_PROFIL) == 0) { 652 p->p_flag |= P_PROFIL; 653 mtx_lock(&time_lock); 654 if (++profprocs == 1) 655 cpu_startprofclock(); 656 mtx_unlock(&time_lock); 657 } 658 } 659 660 /* 661 * Stop profiling on a process. 662 */ 663 void 664 stopprofclock(p) 665 register struct proc *p; 666 { 667 668 PROC_LOCK_ASSERT(p, MA_OWNED); 669 if (p->p_flag & P_PROFIL) { 670 if (p->p_profthreads != 0) { 671 while (p->p_profthreads != 0) { 672 p->p_flag |= P_STOPPROF; 673 msleep(&p->p_profthreads, &p->p_mtx, PPAUSE, 674 "stopprof", 0); 675 } 676 } 677 if ((p->p_flag & P_PROFIL) == 0) 678 return; 679 p->p_flag &= ~P_PROFIL; 680 mtx_lock(&time_lock); 681 if (--profprocs == 0) 682 cpu_stopprofclock(); 683 mtx_unlock(&time_lock); 684 } 685 } 686 687 /* 688 * Statistics clock. Updates rusage information and calls the scheduler 689 * to adjust priorities of the active thread. 690 * 691 * This should be called by all active processors. 692 */ 693 void 694 statclock(int usermode) 695 { 696 697 statclock_cnt(1, usermode); 698 } 699 700 void 701 statclock_cnt(int cnt, int usermode) 702 { 703 struct rusage *ru; 704 struct vmspace *vm; 705 struct thread *td; 706 struct proc *p; 707 long rss; 708 long *cp_time; 709 710 td = curthread; 711 p = td->td_proc; 712 713 cp_time = (long *)PCPU_PTR(cp_time); 714 if (usermode) { 715 /* 716 * Charge the time as appropriate. 717 */ 718 td->td_uticks += cnt; 719 if (p->p_nice > NZERO) 720 cp_time[CP_NICE] += cnt; 721 else 722 cp_time[CP_USER] += cnt; 723 } else { 724 /* 725 * Came from kernel mode, so we were: 726 * - handling an interrupt, 727 * - doing syscall or trap work on behalf of the current 728 * user process, or 729 * - spinning in the idle loop. 730 * Whichever it is, charge the time as appropriate. 731 * Note that we charge interrupts to the current process, 732 * regardless of whether they are ``for'' that process, 733 * so that we know how much of its real time was spent 734 * in ``non-process'' (i.e., interrupt) work. 735 */ 736 if ((td->td_pflags & TDP_ITHREAD) || 737 td->td_intr_nesting_level >= 2) { 738 td->td_iticks += cnt; 739 cp_time[CP_INTR] += cnt; 740 } else { 741 td->td_pticks += cnt; 742 td->td_sticks += cnt; 743 if (!TD_IS_IDLETHREAD(td)) 744 cp_time[CP_SYS] += cnt; 745 else 746 cp_time[CP_IDLE] += cnt; 747 } 748 } 749 750 /* Update resource usage integrals and maximums. */ 751 MPASS(p->p_vmspace != NULL); 752 vm = p->p_vmspace; 753 ru = &td->td_ru; 754 ru->ru_ixrss += pgtok(vm->vm_tsize) * cnt; 755 ru->ru_idrss += pgtok(vm->vm_dsize) * cnt; 756 ru->ru_isrss += pgtok(vm->vm_ssize) * cnt; 757 rss = pgtok(vmspace_resident_count(vm)); 758 if (ru->ru_maxrss < rss) 759 ru->ru_maxrss = rss; 760 KTR_POINT2(KTR_SCHED, "thread", sched_tdname(td), "statclock", 761 "prio:%d", td->td_priority, "stathz:%d", (stathz)?stathz:hz); 762 SDT_PROBE2(sched, , , tick, td, td->td_proc); 763 thread_lock_flags(td, MTX_QUIET); 764 for ( ; cnt > 0; cnt--) 765 sched_clock(td); 766 thread_unlock(td); 767 #ifdef HWPMC_HOOKS 768 if (td->td_intr_frame != NULL) 769 PMC_SOFT_CALL_TF( , , clock, stat, td->td_intr_frame); 770 #endif 771 } 772 773 void 774 profclock(int usermode, uintfptr_t pc) 775 { 776 777 profclock_cnt(1, usermode, pc); 778 } 779 780 void 781 profclock_cnt(int cnt, int usermode, uintfptr_t pc) 782 { 783 struct thread *td; 784 #ifdef GPROF 785 struct gmonparam *g; 786 uintfptr_t i; 787 #endif 788 789 td = curthread; 790 if (usermode) { 791 /* 792 * Came from user mode; CPU was in user state. 793 * If this process is being profiled, record the tick. 794 * if there is no related user location yet, don't 795 * bother trying to count it. 796 */ 797 if (td->td_proc->p_flag & P_PROFIL) 798 addupc_intr(td, pc, cnt); 799 } 800 #ifdef GPROF 801 else { 802 /* 803 * Kernel statistics are just like addupc_intr, only easier. 804 */ 805 g = &_gmonparam; 806 if (g->state == GMON_PROF_ON && pc >= g->lowpc) { 807 i = PC_TO_I(g, pc); 808 if (i < g->textsize) { 809 KCOUNT(g, i) += cnt; 810 } 811 } 812 } 813 #endif 814 #ifdef HWPMC_HOOKS 815 if (td->td_intr_frame != NULL) 816 PMC_SOFT_CALL_TF( , , clock, prof, td->td_intr_frame); 817 #endif 818 } 819 820 /* 821 * Return information about system clocks. 822 */ 823 static int 824 sysctl_kern_clockrate(SYSCTL_HANDLER_ARGS) 825 { 826 struct clockinfo clkinfo; 827 /* 828 * Construct clockinfo structure. 829 */ 830 bzero(&clkinfo, sizeof(clkinfo)); 831 clkinfo.hz = hz; 832 clkinfo.tick = tick; 833 clkinfo.profhz = profhz; 834 clkinfo.stathz = stathz ? stathz : hz; 835 return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req)); 836 } 837 838 SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, 839 CTLTYPE_STRUCT|CTLFLAG_RD|CTLFLAG_MPSAFE, 840 0, 0, sysctl_kern_clockrate, "S,clockinfo", 841 "Rate and period of various kernel clocks"); 842 843 #ifdef SW_WATCHDOG 844 845 static void 846 watchdog_config(void *unused __unused, u_int cmd, int *error) 847 { 848 u_int u; 849 850 u = cmd & WD_INTERVAL; 851 if (u >= WD_TO_1SEC) { 852 watchdog_ticks = (1 << (u - WD_TO_1SEC)) * hz; 853 watchdog_enabled = 1; 854 *error = 0; 855 } else { 856 watchdog_enabled = 0; 857 } 858 } 859 860 /* 861 * Handle a watchdog timeout by dumping interrupt information and 862 * then either dropping to DDB or panicking. 863 */ 864 static void 865 watchdog_fire(void) 866 { 867 int nintr; 868 uint64_t inttotal; 869 u_long *curintr; 870 char *curname; 871 872 curintr = intrcnt; 873 curname = intrnames; 874 inttotal = 0; 875 nintr = sintrcnt / sizeof(u_long); 876 877 printf("interrupt total\n"); 878 while (--nintr >= 0) { 879 if (*curintr) 880 printf("%-12s %20lu\n", curname, *curintr); 881 curname += strlen(curname) + 1; 882 inttotal += *curintr++; 883 } 884 printf("Total %20ju\n", (uintmax_t)inttotal); 885 886 #if defined(KDB) && !defined(KDB_UNATTENDED) 887 kdb_backtrace(); 888 kdb_enter(KDB_WHY_WATCHDOG, "watchdog timeout"); 889 #else 890 panic("watchdog timeout"); 891 #endif 892 } 893 894 #endif /* SW_WATCHDOG */ 895