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_kdtrace.h" 44 #include "opt_ntp.h" 45 #include "opt_watchdog.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/callout.h> 50 #include <sys/kdb.h> 51 #include <sys/kernel.h> 52 #include <sys/kthread.h> 53 #include <sys/ktr.h> 54 #include <sys/lock.h> 55 #include <sys/mutex.h> 56 #include <sys/proc.h> 57 #include <sys/resource.h> 58 #include <sys/resourcevar.h> 59 #include <sys/sched.h> 60 #include <sys/sdt.h> 61 #include <sys/signalvar.h> 62 #include <sys/sleepqueue.h> 63 #include <sys/smp.h> 64 #include <vm/vm.h> 65 #include <vm/pmap.h> 66 #include <vm/vm_map.h> 67 #include <sys/sysctl.h> 68 #include <sys/bus.h> 69 #include <sys/interrupt.h> 70 #include <sys/limits.h> 71 #include <sys/timetc.h> 72 73 #ifdef GPROF 74 #include <sys/gmon.h> 75 #endif 76 77 #ifdef HWPMC_HOOKS 78 #include <sys/pmckern.h> 79 PMC_SOFT_DEFINE( , , clock, hard); 80 PMC_SOFT_DEFINE( , , clock, stat); 81 PMC_SOFT_DEFINE_EX( , , clock, prof, \ 82 cpu_startprofclock, cpu_stopprofclock); 83 #endif 84 85 #ifdef DEVICE_POLLING 86 extern void hardclock_device_poll(void); 87 #endif /* DEVICE_POLLING */ 88 89 static void initclocks(void *dummy); 90 SYSINIT(clocks, SI_SUB_CLOCKS, SI_ORDER_FIRST, initclocks, NULL); 91 92 /* Spin-lock protecting profiling statistics. */ 93 static struct mtx time_lock; 94 95 SDT_PROVIDER_DECLARE(sched); 96 SDT_PROBE_DEFINE2(sched, , , tick, tick, "struct thread *", "struct proc *"); 97 98 static int 99 sysctl_kern_cp_time(SYSCTL_HANDLER_ARGS) 100 { 101 int error; 102 long cp_time[CPUSTATES]; 103 #ifdef SCTL_MASK32 104 int i; 105 unsigned int cp_time32[CPUSTATES]; 106 #endif 107 108 read_cpu_time(cp_time); 109 #ifdef SCTL_MASK32 110 if (req->flags & SCTL_MASK32) { 111 if (!req->oldptr) 112 return SYSCTL_OUT(req, 0, sizeof(cp_time32)); 113 for (i = 0; i < CPUSTATES; i++) 114 cp_time32[i] = (unsigned int)cp_time[i]; 115 error = SYSCTL_OUT(req, cp_time32, sizeof(cp_time32)); 116 } else 117 #endif 118 { 119 if (!req->oldptr) 120 return SYSCTL_OUT(req, 0, sizeof(cp_time)); 121 error = SYSCTL_OUT(req, cp_time, sizeof(cp_time)); 122 } 123 return error; 124 } 125 126 SYSCTL_PROC(_kern, OID_AUTO, cp_time, CTLTYPE_LONG|CTLFLAG_RD|CTLFLAG_MPSAFE, 127 0,0, sysctl_kern_cp_time, "LU", "CPU time statistics"); 128 129 static long empty[CPUSTATES]; 130 131 static int 132 sysctl_kern_cp_times(SYSCTL_HANDLER_ARGS) 133 { 134 struct pcpu *pcpu; 135 int error; 136 int c; 137 long *cp_time; 138 #ifdef SCTL_MASK32 139 unsigned int cp_time32[CPUSTATES]; 140 int i; 141 #endif 142 143 if (!req->oldptr) { 144 #ifdef SCTL_MASK32 145 if (req->flags & SCTL_MASK32) 146 return SYSCTL_OUT(req, 0, sizeof(cp_time32) * (mp_maxid + 1)); 147 else 148 #endif 149 return SYSCTL_OUT(req, 0, sizeof(long) * CPUSTATES * (mp_maxid + 1)); 150 } 151 for (error = 0, c = 0; error == 0 && c <= mp_maxid; c++) { 152 if (!CPU_ABSENT(c)) { 153 pcpu = pcpu_find(c); 154 cp_time = pcpu->pc_cp_time; 155 } else { 156 cp_time = empty; 157 } 158 #ifdef SCTL_MASK32 159 if (req->flags & SCTL_MASK32) { 160 for (i = 0; i < CPUSTATES; i++) 161 cp_time32[i] = (unsigned int)cp_time[i]; 162 error = SYSCTL_OUT(req, cp_time32, sizeof(cp_time32)); 163 } else 164 #endif 165 error = SYSCTL_OUT(req, cp_time, sizeof(long) * CPUSTATES); 166 } 167 return error; 168 } 169 170 SYSCTL_PROC(_kern, OID_AUTO, cp_times, CTLTYPE_LONG|CTLFLAG_RD|CTLFLAG_MPSAFE, 171 0,0, sysctl_kern_cp_times, "LU", "per-CPU time statistics"); 172 173 #ifdef DEADLKRES 174 static const char *blessed[] = { 175 "getblk", 176 "so_snd_sx", 177 "so_rcv_sx", 178 NULL 179 }; 180 static int slptime_threshold = 1800; 181 static int blktime_threshold = 900; 182 static int sleepfreq = 3; 183 184 static void 185 deadlkres(void) 186 { 187 struct proc *p; 188 struct thread *td; 189 void *wchan; 190 int blkticks, i, slpticks, slptype, tryl, tticks; 191 192 tryl = 0; 193 for (;;) { 194 blkticks = blktime_threshold * hz; 195 slpticks = slptime_threshold * hz; 196 197 /* 198 * Avoid to sleep on the sx_lock in order to avoid a possible 199 * priority inversion problem leading to starvation. 200 * If the lock can't be held after 100 tries, panic. 201 */ 202 if (!sx_try_slock(&allproc_lock)) { 203 if (tryl > 100) 204 panic("%s: possible deadlock detected on allproc_lock\n", 205 __func__); 206 tryl++; 207 pause("allproc", sleepfreq * hz); 208 continue; 209 } 210 tryl = 0; 211 FOREACH_PROC_IN_SYSTEM(p) { 212 PROC_LOCK(p); 213 if (p->p_state == PRS_NEW) { 214 PROC_UNLOCK(p); 215 continue; 216 } 217 FOREACH_THREAD_IN_PROC(p, td) { 218 219 /* 220 * Once a thread is found in "interesting" 221 * state a possible ticks wrap-up needs to be 222 * checked. 223 */ 224 thread_lock(td); 225 if (TD_ON_LOCK(td) && ticks < td->td_blktick) { 226 227 /* 228 * The thread should be blocked on a 229 * turnstile, simply check if the 230 * turnstile channel is in good state. 231 */ 232 MPASS(td->td_blocked != NULL); 233 234 tticks = ticks - td->td_blktick; 235 thread_unlock(td); 236 if (tticks > blkticks) { 237 238 /* 239 * Accordingly with provided 240 * thresholds, this thread is 241 * stuck for too long on a 242 * turnstile. 243 */ 244 PROC_UNLOCK(p); 245 sx_sunlock(&allproc_lock); 246 panic("%s: possible deadlock detected for %p, blocked for %d ticks\n", 247 __func__, td, tticks); 248 } 249 } else if (TD_IS_SLEEPING(td) && 250 TD_ON_SLEEPQ(td) && 251 ticks < td->td_blktick) { 252 253 /* 254 * Check if the thread is sleeping on a 255 * lock, otherwise skip the check. 256 * Drop the thread lock in order to 257 * avoid a LOR with the sleepqueue 258 * spinlock. 259 */ 260 wchan = td->td_wchan; 261 tticks = ticks - td->td_slptick; 262 thread_unlock(td); 263 slptype = sleepq_type(wchan); 264 if ((slptype == SLEEPQ_SX || 265 slptype == SLEEPQ_LK) && 266 tticks > slpticks) { 267 268 /* 269 * Accordingly with provided 270 * thresholds, this thread is 271 * stuck for too long on a 272 * sleepqueue. 273 * However, being on a 274 * sleepqueue, we might still 275 * check for the blessed 276 * list. 277 */ 278 tryl = 0; 279 for (i = 0; blessed[i] != NULL; 280 i++) { 281 if (!strcmp(blessed[i], 282 td->td_wmesg)) { 283 tryl = 1; 284 break; 285 } 286 } 287 if (tryl != 0) { 288 tryl = 0; 289 continue; 290 } 291 PROC_UNLOCK(p); 292 sx_sunlock(&allproc_lock); 293 panic("%s: possible deadlock detected for %p, blocked for %d ticks\n", 294 __func__, td, tticks); 295 } 296 } else 297 thread_unlock(td); 298 } 299 PROC_UNLOCK(p); 300 } 301 sx_sunlock(&allproc_lock); 302 303 /* Sleep for sleepfreq seconds. */ 304 pause("-", sleepfreq * hz); 305 } 306 } 307 308 static struct kthread_desc deadlkres_kd = { 309 "deadlkres", 310 deadlkres, 311 (struct thread **)NULL 312 }; 313 314 SYSINIT(deadlkres, SI_SUB_CLOCKS, SI_ORDER_ANY, kthread_start, &deadlkres_kd); 315 316 static SYSCTL_NODE(_debug, OID_AUTO, deadlkres, CTLFLAG_RW, 0, 317 "Deadlock resolver"); 318 SYSCTL_INT(_debug_deadlkres, OID_AUTO, slptime_threshold, CTLFLAG_RW, 319 &slptime_threshold, 0, 320 "Number of seconds within is valid to sleep on a sleepqueue"); 321 SYSCTL_INT(_debug_deadlkres, OID_AUTO, blktime_threshold, CTLFLAG_RW, 322 &blktime_threshold, 0, 323 "Number of seconds within is valid to block on a turnstile"); 324 SYSCTL_INT(_debug_deadlkres, OID_AUTO, sleepfreq, CTLFLAG_RW, &sleepfreq, 0, 325 "Number of seconds between any deadlock resolver thread run"); 326 #endif /* DEADLKRES */ 327 328 void 329 read_cpu_time(long *cp_time) 330 { 331 struct pcpu *pc; 332 int i, j; 333 334 /* Sum up global cp_time[]. */ 335 bzero(cp_time, sizeof(long) * CPUSTATES); 336 CPU_FOREACH(i) { 337 pc = pcpu_find(i); 338 for (j = 0; j < CPUSTATES; j++) 339 cp_time[j] += pc->pc_cp_time[j]; 340 } 341 } 342 343 #ifdef SW_WATCHDOG 344 #include <sys/watchdog.h> 345 346 static int watchdog_ticks; 347 static int watchdog_enabled; 348 static void watchdog_fire(void); 349 static void watchdog_config(void *, u_int, int *); 350 #endif /* SW_WATCHDOG */ 351 352 /* 353 * Clock handling routines. 354 * 355 * This code is written to operate with two timers that run independently of 356 * each other. 357 * 358 * The main timer, running hz times per second, is used to trigger interval 359 * timers, timeouts and rescheduling as needed. 360 * 361 * The second timer handles kernel and user profiling, 362 * and does resource use estimation. If the second timer is programmable, 363 * it is randomized to avoid aliasing between the two clocks. For example, 364 * the randomization prevents an adversary from always giving up the cpu 365 * just before its quantum expires. Otherwise, it would never accumulate 366 * cpu ticks. The mean frequency of the second timer is stathz. 367 * 368 * If no second timer exists, stathz will be zero; in this case we drive 369 * profiling and statistics off the main clock. This WILL NOT be accurate; 370 * do not do it unless absolutely necessary. 371 * 372 * The statistics clock may (or may not) be run at a higher rate while 373 * profiling. This profile clock runs at profhz. We require that profhz 374 * be an integral multiple of stathz. 375 * 376 * If the statistics clock is running fast, it must be divided by the ratio 377 * profhz/stathz for statistics. (For profiling, every tick counts.) 378 * 379 * Time-of-day is maintained using a "timecounter", which may or may 380 * not be related to the hardware generating the above mentioned 381 * interrupts. 382 */ 383 384 int stathz; 385 int profhz; 386 int profprocs; 387 volatile int ticks; 388 int psratio; 389 390 static DPCPU_DEFINE(int, pcputicks); /* Per-CPU version of ticks. */ 391 static int global_hardclock_run = 0; 392 393 /* 394 * Initialize clock frequencies and start both clocks running. 395 */ 396 /* ARGSUSED*/ 397 static void 398 initclocks(dummy) 399 void *dummy; 400 { 401 register int i; 402 403 /* 404 * Set divisors to 1 (normal case) and let the machine-specific 405 * code do its bit. 406 */ 407 mtx_init(&time_lock, "time lock", NULL, MTX_DEF); 408 cpu_initclocks(); 409 410 /* 411 * Compute profhz/stathz, and fix profhz if needed. 412 */ 413 i = stathz ? stathz : hz; 414 if (profhz == 0) 415 profhz = i; 416 psratio = profhz / i; 417 #ifdef SW_WATCHDOG 418 EVENTHANDLER_REGISTER(watchdog_list, watchdog_config, NULL, 0); 419 #endif 420 } 421 422 /* 423 * Each time the real-time timer fires, this function is called on all CPUs. 424 * Note that hardclock() calls hardclock_cpu() for the boot CPU, so only 425 * the other CPUs in the system need to call this function. 426 */ 427 void 428 hardclock_cpu(int usermode) 429 { 430 struct pstats *pstats; 431 struct thread *td = curthread; 432 struct proc *p = td->td_proc; 433 int flags; 434 435 /* 436 * Run current process's virtual and profile time, as needed. 437 */ 438 pstats = p->p_stats; 439 flags = 0; 440 if (usermode && 441 timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value)) { 442 PROC_SLOCK(p); 443 if (itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], tick) == 0) 444 flags |= TDF_ALRMPEND | TDF_ASTPENDING; 445 PROC_SUNLOCK(p); 446 } 447 if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value)) { 448 PROC_SLOCK(p); 449 if (itimerdecr(&pstats->p_timer[ITIMER_PROF], tick) == 0) 450 flags |= TDF_PROFPEND | TDF_ASTPENDING; 451 PROC_SUNLOCK(p); 452 } 453 thread_lock(td); 454 sched_tick(1); 455 td->td_flags |= flags; 456 thread_unlock(td); 457 458 #ifdef HWPMC_HOOKS 459 if (PMC_CPU_HAS_SAMPLES(PCPU_GET(cpuid))) 460 PMC_CALL_HOOK_UNLOCKED(curthread, PMC_FN_DO_SAMPLES, NULL); 461 if (td->td_intr_frame != NULL) 462 PMC_SOFT_CALL_TF( , , clock, hard, td->td_intr_frame); 463 #endif 464 callout_process(sbinuptime()); 465 } 466 467 /* 468 * The real-time timer, interrupting hz times per second. 469 */ 470 void 471 hardclock(int usermode, uintfptr_t pc) 472 { 473 474 atomic_add_int(&ticks, 1); 475 hardclock_cpu(usermode); 476 tc_ticktock(1); 477 cpu_tick_calibration(); 478 /* 479 * If no separate statistics clock is available, run it from here. 480 * 481 * XXX: this only works for UP 482 */ 483 if (stathz == 0) { 484 profclock(usermode, pc); 485 statclock(usermode); 486 } 487 #ifdef DEVICE_POLLING 488 hardclock_device_poll(); /* this is very short and quick */ 489 #endif /* DEVICE_POLLING */ 490 #ifdef SW_WATCHDOG 491 if (watchdog_enabled > 0 && --watchdog_ticks <= 0) 492 watchdog_fire(); 493 #endif /* SW_WATCHDOG */ 494 } 495 496 void 497 hardclock_cnt(int cnt, int usermode) 498 { 499 struct pstats *pstats; 500 struct thread *td = curthread; 501 struct proc *p = td->td_proc; 502 int *t = DPCPU_PTR(pcputicks); 503 int flags, global, newticks; 504 #ifdef SW_WATCHDOG 505 int i; 506 #endif /* SW_WATCHDOG */ 507 508 /* 509 * Update per-CPU and possibly global ticks values. 510 */ 511 *t += cnt; 512 do { 513 global = ticks; 514 newticks = *t - global; 515 if (newticks <= 0) { 516 if (newticks < -1) 517 *t = global - 1; 518 newticks = 0; 519 break; 520 } 521 } while (!atomic_cmpset_int(&ticks, global, *t)); 522 523 /* 524 * Run current process's virtual and profile time, as needed. 525 */ 526 pstats = p->p_stats; 527 flags = 0; 528 if (usermode && 529 timevalisset(&pstats->p_timer[ITIMER_VIRTUAL].it_value)) { 530 PROC_SLOCK(p); 531 if (itimerdecr(&pstats->p_timer[ITIMER_VIRTUAL], 532 tick * cnt) == 0) 533 flags |= TDF_ALRMPEND | TDF_ASTPENDING; 534 PROC_SUNLOCK(p); 535 } 536 if (timevalisset(&pstats->p_timer[ITIMER_PROF].it_value)) { 537 PROC_SLOCK(p); 538 if (itimerdecr(&pstats->p_timer[ITIMER_PROF], 539 tick * cnt) == 0) 540 flags |= TDF_PROFPEND | TDF_ASTPENDING; 541 PROC_SUNLOCK(p); 542 } 543 thread_lock(td); 544 sched_tick(cnt); 545 td->td_flags |= flags; 546 thread_unlock(td); 547 548 #ifdef HWPMC_HOOKS 549 if (PMC_CPU_HAS_SAMPLES(PCPU_GET(cpuid))) 550 PMC_CALL_HOOK_UNLOCKED(curthread, PMC_FN_DO_SAMPLES, NULL); 551 if (td->td_intr_frame != NULL) 552 PMC_SOFT_CALL_TF( , , clock, hard, td->td_intr_frame); 553 #endif 554 /* We are in charge to handle this tick duty. */ 555 if (newticks > 0) { 556 /* Dangerous and no need to call these things concurrently. */ 557 if (atomic_cmpset_acq_int(&global_hardclock_run, 0, 1)) { 558 tc_ticktock(newticks); 559 #ifdef DEVICE_POLLING 560 /* This is very short and quick. */ 561 hardclock_device_poll(); 562 #endif /* DEVICE_POLLING */ 563 atomic_store_rel_int(&global_hardclock_run, 0); 564 } 565 #ifdef SW_WATCHDOG 566 if (watchdog_enabled > 0) { 567 i = atomic_fetchadd_int(&watchdog_ticks, -newticks); 568 if (i > 0 && i <= newticks) 569 watchdog_fire(); 570 } 571 #endif /* SW_WATCHDOG */ 572 } 573 if (curcpu == CPU_FIRST()) 574 cpu_tick_calibration(); 575 } 576 577 void 578 hardclock_sync(int cpu) 579 { 580 int *t = DPCPU_ID_PTR(cpu, pcputicks); 581 582 *t = ticks; 583 } 584 585 /* 586 * Compute number of ticks in the specified amount of time. 587 */ 588 int 589 tvtohz(tv) 590 struct timeval *tv; 591 { 592 register unsigned long ticks; 593 register long sec, usec; 594 595 /* 596 * If the number of usecs in the whole seconds part of the time 597 * difference fits in a long, then the total number of usecs will 598 * fit in an unsigned long. Compute the total and convert it to 599 * ticks, rounding up and adding 1 to allow for the current tick 600 * to expire. Rounding also depends on unsigned long arithmetic 601 * to avoid overflow. 602 * 603 * Otherwise, if the number of ticks in the whole seconds part of 604 * the time difference fits in a long, then convert the parts to 605 * ticks separately and add, using similar rounding methods and 606 * overflow avoidance. This method would work in the previous 607 * case but it is slightly slower and assumes that hz is integral. 608 * 609 * Otherwise, round the time difference down to the maximum 610 * representable value. 611 * 612 * If ints have 32 bits, then the maximum value for any timeout in 613 * 10ms ticks is 248 days. 614 */ 615 sec = tv->tv_sec; 616 usec = tv->tv_usec; 617 if (usec < 0) { 618 sec--; 619 usec += 1000000; 620 } 621 if (sec < 0) { 622 #ifdef DIAGNOSTIC 623 if (usec > 0) { 624 sec++; 625 usec -= 1000000; 626 } 627 printf("tvotohz: negative time difference %ld sec %ld usec\n", 628 sec, usec); 629 #endif 630 ticks = 1; 631 } else if (sec <= LONG_MAX / 1000000) 632 ticks = (sec * 1000000 + (unsigned long)usec + (tick - 1)) 633 / tick + 1; 634 else if (sec <= LONG_MAX / hz) 635 ticks = sec * hz 636 + ((unsigned long)usec + (tick - 1)) / tick + 1; 637 else 638 ticks = LONG_MAX; 639 if (ticks > INT_MAX) 640 ticks = INT_MAX; 641 return ((int)ticks); 642 } 643 644 /* 645 * Start profiling on a process. 646 * 647 * Kernel profiling passes proc0 which never exits and hence 648 * keeps the profile clock running constantly. 649 */ 650 void 651 startprofclock(p) 652 register struct proc *p; 653 { 654 655 PROC_LOCK_ASSERT(p, MA_OWNED); 656 if (p->p_flag & P_STOPPROF) 657 return; 658 if ((p->p_flag & P_PROFIL) == 0) { 659 p->p_flag |= P_PROFIL; 660 mtx_lock(&time_lock); 661 if (++profprocs == 1) 662 cpu_startprofclock(); 663 mtx_unlock(&time_lock); 664 } 665 } 666 667 /* 668 * Stop profiling on a process. 669 */ 670 void 671 stopprofclock(p) 672 register struct proc *p; 673 { 674 675 PROC_LOCK_ASSERT(p, MA_OWNED); 676 if (p->p_flag & P_PROFIL) { 677 if (p->p_profthreads != 0) { 678 p->p_flag |= P_STOPPROF; 679 while (p->p_profthreads != 0) 680 msleep(&p->p_profthreads, &p->p_mtx, PPAUSE, 681 "stopprof", 0); 682 p->p_flag &= ~P_STOPPROF; 683 } 684 if ((p->p_flag & P_PROFIL) == 0) 685 return; 686 p->p_flag &= ~P_PROFIL; 687 mtx_lock(&time_lock); 688 if (--profprocs == 0) 689 cpu_stopprofclock(); 690 mtx_unlock(&time_lock); 691 } 692 } 693 694 /* 695 * Statistics clock. Updates rusage information and calls the scheduler 696 * to adjust priorities of the active thread. 697 * 698 * This should be called by all active processors. 699 */ 700 void 701 statclock(int usermode) 702 { 703 704 statclock_cnt(1, usermode); 705 } 706 707 void 708 statclock_cnt(int cnt, int usermode) 709 { 710 struct rusage *ru; 711 struct vmspace *vm; 712 struct thread *td; 713 struct proc *p; 714 long rss; 715 long *cp_time; 716 717 td = curthread; 718 p = td->td_proc; 719 720 cp_time = (long *)PCPU_PTR(cp_time); 721 if (usermode) { 722 /* 723 * Charge the time as appropriate. 724 */ 725 td->td_uticks += cnt; 726 if (p->p_nice > NZERO) 727 cp_time[CP_NICE] += cnt; 728 else 729 cp_time[CP_USER] += cnt; 730 } else { 731 /* 732 * Came from kernel mode, so we were: 733 * - handling an interrupt, 734 * - doing syscall or trap work on behalf of the current 735 * user process, or 736 * - spinning in the idle loop. 737 * Whichever it is, charge the time as appropriate. 738 * Note that we charge interrupts to the current process, 739 * regardless of whether they are ``for'' that process, 740 * so that we know how much of its real time was spent 741 * in ``non-process'' (i.e., interrupt) work. 742 */ 743 if ((td->td_pflags & TDP_ITHREAD) || 744 td->td_intr_nesting_level >= 2) { 745 td->td_iticks += cnt; 746 cp_time[CP_INTR] += cnt; 747 } else { 748 td->td_pticks += cnt; 749 td->td_sticks += cnt; 750 if (!TD_IS_IDLETHREAD(td)) 751 cp_time[CP_SYS] += cnt; 752 else 753 cp_time[CP_IDLE] += cnt; 754 } 755 } 756 757 /* Update resource usage integrals and maximums. */ 758 MPASS(p->p_vmspace != NULL); 759 vm = p->p_vmspace; 760 ru = &td->td_ru; 761 ru->ru_ixrss += pgtok(vm->vm_tsize) * cnt; 762 ru->ru_idrss += pgtok(vm->vm_dsize) * cnt; 763 ru->ru_isrss += pgtok(vm->vm_ssize) * cnt; 764 rss = pgtok(vmspace_resident_count(vm)); 765 if (ru->ru_maxrss < rss) 766 ru->ru_maxrss = rss; 767 KTR_POINT2(KTR_SCHED, "thread", sched_tdname(td), "statclock", 768 "prio:%d", td->td_priority, "stathz:%d", (stathz)?stathz:hz); 769 SDT_PROBE2(sched, , , tick, td, td->td_proc); 770 thread_lock_flags(td, MTX_QUIET); 771 for ( ; cnt > 0; cnt--) 772 sched_clock(td); 773 thread_unlock(td); 774 #ifdef HWPMC_HOOKS 775 if (td->td_intr_frame != NULL) 776 PMC_SOFT_CALL_TF( , , clock, stat, td->td_intr_frame); 777 #endif 778 } 779 780 void 781 profclock(int usermode, uintfptr_t pc) 782 { 783 784 profclock_cnt(1, usermode, pc); 785 } 786 787 void 788 profclock_cnt(int cnt, int usermode, uintfptr_t pc) 789 { 790 struct thread *td; 791 #ifdef GPROF 792 struct gmonparam *g; 793 uintfptr_t i; 794 #endif 795 796 td = curthread; 797 if (usermode) { 798 /* 799 * Came from user mode; CPU was in user state. 800 * If this process is being profiled, record the tick. 801 * if there is no related user location yet, don't 802 * bother trying to count it. 803 */ 804 if (td->td_proc->p_flag & P_PROFIL) 805 addupc_intr(td, pc, cnt); 806 } 807 #ifdef GPROF 808 else { 809 /* 810 * Kernel statistics are just like addupc_intr, only easier. 811 */ 812 g = &_gmonparam; 813 if (g->state == GMON_PROF_ON && pc >= g->lowpc) { 814 i = PC_TO_I(g, pc); 815 if (i < g->textsize) { 816 KCOUNT(g, i) += cnt; 817 } 818 } 819 } 820 #endif 821 #ifdef HWPMC_HOOKS 822 if (td->td_intr_frame != NULL) 823 PMC_SOFT_CALL_TF( , , clock, prof, td->td_intr_frame); 824 #endif 825 } 826 827 /* 828 * Return information about system clocks. 829 */ 830 static int 831 sysctl_kern_clockrate(SYSCTL_HANDLER_ARGS) 832 { 833 struct clockinfo clkinfo; 834 /* 835 * Construct clockinfo structure. 836 */ 837 bzero(&clkinfo, sizeof(clkinfo)); 838 clkinfo.hz = hz; 839 clkinfo.tick = tick; 840 clkinfo.profhz = profhz; 841 clkinfo.stathz = stathz ? stathz : hz; 842 return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req)); 843 } 844 845 SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, 846 CTLTYPE_STRUCT|CTLFLAG_RD|CTLFLAG_MPSAFE, 847 0, 0, sysctl_kern_clockrate, "S,clockinfo", 848 "Rate and period of various kernel clocks"); 849 850 #ifdef SW_WATCHDOG 851 852 static void 853 watchdog_config(void *unused __unused, u_int cmd, int *error) 854 { 855 u_int u; 856 857 u = cmd & WD_INTERVAL; 858 if (u >= WD_TO_1SEC) { 859 watchdog_ticks = (1 << (u - WD_TO_1SEC)) * hz; 860 watchdog_enabled = 1; 861 *error = 0; 862 } else { 863 watchdog_enabled = 0; 864 } 865 } 866 867 /* 868 * Handle a watchdog timeout by dumping interrupt information and 869 * then either dropping to DDB or panicking. 870 */ 871 static void 872 watchdog_fire(void) 873 { 874 int nintr; 875 uint64_t inttotal; 876 u_long *curintr; 877 char *curname; 878 879 curintr = intrcnt; 880 curname = intrnames; 881 inttotal = 0; 882 nintr = sintrcnt / sizeof(u_long); 883 884 printf("interrupt total\n"); 885 while (--nintr >= 0) { 886 if (*curintr) 887 printf("%-12s %20lu\n", curname, *curintr); 888 curname += strlen(curname) + 1; 889 inttotal += *curintr++; 890 } 891 printf("Total %20ju\n", (uintmax_t)inttotal); 892 893 #if defined(KDB) && !defined(KDB_UNATTENDED) 894 kdb_backtrace(); 895 kdb_enter(KDB_WHY_WATCHDOG, "watchdog timeout"); 896 #else 897 panic("watchdog timeout"); 898 #endif 899 } 900 901 #endif /* SW_WATCHDOG */ 902