1 /* 2 * Copyright (c) 2003,2004 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * Copyright (c) 1997, 1998 Poul-Henning Kamp <phk@FreeBSD.org> 35 * Copyright (c) 1982, 1986, 1991, 1993 36 * The Regents of the University of California. All rights reserved. 37 * (c) UNIX System Laboratories, Inc. 38 * All or some portions of this file are derived from material licensed 39 * to the University of California by American Telephone and Telegraph 40 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 41 * the permission of UNIX System Laboratories, Inc. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. Neither the name of the University nor the names of its contributors 52 * may be used to endorse or promote products derived from this software 53 * without specific prior written permission. 54 * 55 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 56 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 57 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 58 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 59 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 60 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 61 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 62 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 63 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 64 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 65 * SUCH DAMAGE. 66 * 67 * @(#)kern_clock.c 8.5 (Berkeley) 1/21/94 68 * $FreeBSD: src/sys/kern/kern_clock.c,v 1.105.2.10 2002/10/17 13:19:40 maxim Exp $ 69 */ 70 71 #include "opt_ntp.h" 72 #include "opt_pctrack.h" 73 74 #include <sys/param.h> 75 #include <sys/systm.h> 76 #include <sys/callout.h> 77 #include <sys/kernel.h> 78 #include <sys/kinfo.h> 79 #include <sys/proc.h> 80 #include <sys/malloc.h> 81 #include <sys/resource.h> 82 #include <sys/resourcevar.h> 83 #include <sys/signalvar.h> 84 #include <sys/priv.h> 85 #include <sys/timex.h> 86 #include <sys/timepps.h> 87 #include <sys/upmap.h> 88 #include <sys/lock.h> 89 #include <sys/sysctl.h> 90 #include <sys/kcollect.h> 91 92 #include <vm/vm.h> 93 #include <vm/pmap.h> 94 #include <vm/vm_map.h> 95 #include <vm/vm_extern.h> 96 97 #include <sys/thread2.h> 98 #include <sys/spinlock2.h> 99 100 #include <machine/cpu.h> 101 #include <machine/limits.h> 102 #include <machine/smp.h> 103 #include <machine/cpufunc.h> 104 #include <machine/specialreg.h> 105 #include <machine/clock.h> 106 107 #ifdef DEBUG_PCTRACK 108 static void do_pctrack(struct intrframe *frame, int which); 109 #endif 110 111 static void initclocks (void *dummy); 112 SYSINIT(clocks, SI_BOOT2_CLOCKS, SI_ORDER_FIRST, initclocks, NULL); 113 114 /* 115 * Some of these don't belong here, but it's easiest to concentrate them. 116 * Note that cpu_time counts in microseconds, but most userland programs 117 * just compare relative times against the total by delta. 118 */ 119 struct kinfo_cputime cputime_percpu[MAXCPU]; 120 #ifdef DEBUG_PCTRACK 121 struct kinfo_pcheader cputime_pcheader = { PCTRACK_SIZE, PCTRACK_ARYSIZE }; 122 struct kinfo_pctrack cputime_pctrack[MAXCPU][PCTRACK_SIZE]; 123 #endif 124 125 __read_mostly static int sniff_enable = 1; 126 __read_mostly static int sniff_target = -1; 127 __read_mostly static int clock_debug2 = 0; 128 SYSCTL_INT(_kern, OID_AUTO, sniff_enable, CTLFLAG_RW, &sniff_enable, 0 , ""); 129 SYSCTL_INT(_kern, OID_AUTO, sniff_target, CTLFLAG_RW, &sniff_target, 0 , ""); 130 SYSCTL_INT(_debug, OID_AUTO, clock_debug2, CTLFLAG_RW, &clock_debug2, 0 , ""); 131 132 static int 133 sysctl_cputime(SYSCTL_HANDLER_ARGS) 134 { 135 int cpu, error = 0; 136 int root_error; 137 size_t size = sizeof(struct kinfo_cputime); 138 struct kinfo_cputime tmp; 139 140 /* 141 * NOTE: For security reasons, only root can sniff %rip 142 */ 143 root_error = priv_check_cred(curthread->td_ucred, PRIV_ROOT, 0); 144 145 for (cpu = 0; cpu < ncpus; ++cpu) { 146 tmp = cputime_percpu[cpu]; 147 if (root_error == 0) { 148 tmp.cp_sample_pc = 149 (int64_t)globaldata_find(cpu)->gd_sample_pc; 150 tmp.cp_sample_sp = 151 (int64_t)globaldata_find(cpu)->gd_sample_sp; 152 } 153 if ((error = SYSCTL_OUT(req, &tmp, size)) != 0) 154 break; 155 } 156 157 if (root_error == 0) { 158 if (sniff_enable) { 159 int n = sniff_target; 160 if (n < 0) 161 smp_sniff(); 162 else if (n < ncpus) 163 cpu_sniff(n); 164 } 165 } 166 167 return (error); 168 } 169 SYSCTL_PROC(_kern, OID_AUTO, cputime, (CTLTYPE_OPAQUE|CTLFLAG_RD), 0, 0, 170 sysctl_cputime, "S,kinfo_cputime", "CPU time statistics"); 171 172 static int 173 sysctl_cp_time(SYSCTL_HANDLER_ARGS) 174 { 175 long cpu_states[CPUSTATES] = {0}; 176 int cpu, error = 0; 177 size_t size = sizeof(cpu_states); 178 179 for (cpu = 0; cpu < ncpus; ++cpu) { 180 cpu_states[CP_USER] += cputime_percpu[cpu].cp_user; 181 cpu_states[CP_NICE] += cputime_percpu[cpu].cp_nice; 182 cpu_states[CP_SYS] += cputime_percpu[cpu].cp_sys; 183 cpu_states[CP_INTR] += cputime_percpu[cpu].cp_intr; 184 cpu_states[CP_IDLE] += cputime_percpu[cpu].cp_idle; 185 } 186 187 error = SYSCTL_OUT(req, cpu_states, size); 188 189 return (error); 190 } 191 192 SYSCTL_PROC(_kern, OID_AUTO, cp_time, (CTLTYPE_LONG|CTLFLAG_RD), 0, 0, 193 sysctl_cp_time, "LU", "CPU time statistics"); 194 195 static int 196 sysctl_cp_times(SYSCTL_HANDLER_ARGS) 197 { 198 long cpu_states[CPUSTATES] = {0}; 199 int cpu, error; 200 size_t size = sizeof(cpu_states); 201 202 for (error = 0, cpu = 0; error == 0 && cpu < ncpus; ++cpu) { 203 cpu_states[CP_USER] = cputime_percpu[cpu].cp_user; 204 cpu_states[CP_NICE] = cputime_percpu[cpu].cp_nice; 205 cpu_states[CP_SYS] = cputime_percpu[cpu].cp_sys; 206 cpu_states[CP_INTR] = cputime_percpu[cpu].cp_intr; 207 cpu_states[CP_IDLE] = cputime_percpu[cpu].cp_idle; 208 error = SYSCTL_OUT(req, cpu_states, size); 209 } 210 211 return (error); 212 } 213 214 SYSCTL_PROC(_kern, OID_AUTO, cp_times, (CTLTYPE_LONG|CTLFLAG_RD), 0, 0, 215 sysctl_cp_times, "LU", "per-CPU time statistics"); 216 217 /* 218 * boottime is used to calculate the 'real' uptime. Do not confuse this with 219 * microuptime(). microtime() is not drift compensated. The real uptime 220 * with compensation is nanotime() - bootime. boottime is recalculated 221 * whenever the real time is set based on the compensated elapsed time 222 * in seconds (gd->gd_time_seconds). 223 * 224 * The gd_time_seconds and gd_cpuclock_base fields remain fairly monotonic. 225 * Slight adjustments to gd_cpuclock_base are made to phase-lock it to 226 * the real time. 227 * 228 * WARNING! time_second can backstep on time corrections. Also, unlike 229 * time_second, time_uptime is not a "real" time_t (seconds 230 * since the Epoch) but seconds since booting. 231 */ 232 __read_mostly struct timespec boottime; /* boot time (realtime) for ref only */ 233 __read_mostly struct timespec ticktime0;/* updated every tick */ 234 __read_mostly struct timespec ticktime2;/* updated every tick */ 235 __read_mostly int ticktime_update; 236 __read_mostly time_t time_second; /* read-only 'passive' rt in seconds */ 237 __read_mostly time_t time_uptime; /* read-only 'passive' ut in seconds */ 238 239 /* 240 * basetime is used to calculate the compensated real time of day. The 241 * basetime can be modified on a per-tick basis by the adjtime(), 242 * ntp_adjtime(), and sysctl-based time correction APIs. 243 * 244 * Note that frequency corrections can also be made by adjusting 245 * gd_cpuclock_base. 246 * 247 * basetime is a tail-chasing FIFO, updated only by cpu #0. The FIFO is 248 * used on both SMP and UP systems to avoid MP races between cpu's and 249 * interrupt races on UP systems. 250 */ 251 struct hardtime { 252 __uint32_t time_second; 253 sysclock_t cpuclock_base; 254 }; 255 256 #define BASETIME_ARYSIZE 16 257 #define BASETIME_ARYMASK (BASETIME_ARYSIZE - 1) 258 static struct timespec basetime[BASETIME_ARYSIZE]; 259 static struct hardtime hardtime[BASETIME_ARYSIZE]; 260 static volatile int basetime_index; 261 262 static int 263 sysctl_get_basetime(SYSCTL_HANDLER_ARGS) 264 { 265 struct timespec *bt; 266 int error; 267 int index; 268 269 /* 270 * Because basetime data and index may be updated by another cpu, 271 * a load fence is required to ensure that the data we read has 272 * not been speculatively read relative to a possibly updated index. 273 */ 274 index = basetime_index; 275 cpu_lfence(); 276 bt = &basetime[index]; 277 error = SYSCTL_OUT(req, bt, sizeof(*bt)); 278 return (error); 279 } 280 281 SYSCTL_STRUCT(_kern, KERN_BOOTTIME, boottime, CTLFLAG_RD, 282 &boottime, timespec, "System boottime"); 283 SYSCTL_PROC(_kern, OID_AUTO, basetime, CTLTYPE_STRUCT|CTLFLAG_RD, 0, 0, 284 sysctl_get_basetime, "S,timespec", "System basetime"); 285 286 static void hardclock(systimer_t info, int, struct intrframe *frame); 287 static void statclock(systimer_t info, int, struct intrframe *frame); 288 static void schedclock(systimer_t info, int, struct intrframe *frame); 289 static void getnanotime_nbt(struct timespec *nbt, struct timespec *tsp); 290 291 /* 292 * Use __read_mostly for ticks and sched_ticks because these variables are 293 * used all over the kernel and only updated once per tick. 294 */ 295 __read_mostly int ticks; /* system master ticks at hz */ 296 __read_mostly int sched_ticks; /* global schedule clock ticks */ 297 __read_mostly int clocks_running; /* tsleep/timeout clocks operational */ 298 int64_t nsec_adj; /* ntpd per-tick adjustment in nsec << 32 */ 299 int64_t nsec_acc; /* accumulator */ 300 301 /* NTPD time correction fields */ 302 int64_t ntp_tick_permanent; /* per-tick adjustment in nsec << 32 */ 303 int64_t ntp_tick_acc; /* accumulator for per-tick adjustment */ 304 int64_t ntp_delta; /* one-time correction in nsec */ 305 int64_t ntp_big_delta = 1000000000; 306 int32_t ntp_tick_delta; /* current adjustment rate */ 307 int32_t ntp_default_tick_delta; /* adjustment rate for ntp_delta */ 308 time_t ntp_leap_second; /* time of next leap second */ 309 int ntp_leap_insert; /* whether to insert or remove a second */ 310 struct spinlock ntp_spin; 311 312 /* 313 * Finish initializing clock frequencies and start all clocks running. 314 */ 315 /* ARGSUSED*/ 316 static void 317 initclocks(void *dummy) 318 { 319 /*psratio = profhz / stathz;*/ 320 spin_init(&ntp_spin, "ntp"); 321 initclocks_pcpu(); 322 clocks_running = 1; 323 if (kpmap) { 324 kpmap->tsc_freq = tsc_frequency; 325 kpmap->tick_freq = hz; 326 } 327 } 328 329 /* 330 * Called on a per-cpu basis from the idle thread bootstrap on each cpu 331 * during SMP initialization. 332 * 333 * This routine is called concurrently during low-level SMP initialization 334 * and may not block in any way. Meaning, among other things, we can't 335 * acquire any tokens. 336 */ 337 void 338 initclocks_pcpu(void) 339 { 340 struct globaldata *gd = mycpu; 341 342 crit_enter(); 343 if (gd->gd_cpuid == 0) { 344 gd->gd_time_seconds = 1; 345 gd->gd_cpuclock_base = sys_cputimer->count(); 346 hardtime[0].time_second = gd->gd_time_seconds; 347 hardtime[0].cpuclock_base = gd->gd_cpuclock_base; 348 } else { 349 gd->gd_time_seconds = globaldata_find(0)->gd_time_seconds; 350 gd->gd_cpuclock_base = globaldata_find(0)->gd_cpuclock_base; 351 } 352 353 systimer_intr_enable(); 354 355 crit_exit(); 356 } 357 358 /* 359 * Called on a 10-second interval after the system is operational. 360 * Return the collection data for USERPCT and install the data for 361 * SYSTPCT and IDLEPCT. 362 */ 363 static 364 uint64_t 365 collect_cputime_callback(int n) 366 { 367 static long cpu_base[CPUSTATES]; 368 long cpu_states[CPUSTATES]; 369 long total; 370 long acc; 371 long lsb; 372 373 bzero(cpu_states, sizeof(cpu_states)); 374 for (n = 0; n < ncpus; ++n) { 375 cpu_states[CP_USER] += cputime_percpu[n].cp_user; 376 cpu_states[CP_NICE] += cputime_percpu[n].cp_nice; 377 cpu_states[CP_SYS] += cputime_percpu[n].cp_sys; 378 cpu_states[CP_INTR] += cputime_percpu[n].cp_intr; 379 cpu_states[CP_IDLE] += cputime_percpu[n].cp_idle; 380 } 381 382 acc = 0; 383 for (n = 0; n < CPUSTATES; ++n) { 384 total = cpu_states[n] - cpu_base[n]; 385 cpu_base[n] = cpu_states[n]; 386 cpu_states[n] = total; 387 acc += total; 388 } 389 if (acc == 0) /* prevent degenerate divide by 0 */ 390 acc = 1; 391 lsb = acc / (10000 * 2); 392 kcollect_setvalue(KCOLLECT_SYSTPCT, 393 (cpu_states[CP_SYS] + lsb) * 10000 / acc); 394 kcollect_setvalue(KCOLLECT_IDLEPCT, 395 (cpu_states[CP_IDLE] + lsb) * 10000 / acc); 396 kcollect_setvalue(KCOLLECT_INTRPCT, 397 (cpu_states[CP_INTR] + lsb) * 10000 / acc); 398 return((cpu_states[CP_USER] + cpu_states[CP_NICE] + lsb) * 10000 / acc); 399 } 400 401 /* 402 * This routine is called on just the BSP, just after SMP initialization 403 * completes to * finish initializing any clocks that might contend/block 404 * (e.g. like on a token). We can't do this in initclocks_pcpu() because 405 * that function is called from the idle thread bootstrap for each cpu and 406 * not allowed to block at all. 407 */ 408 static 409 void 410 initclocks_other(void *dummy) 411 { 412 struct globaldata *ogd = mycpu; 413 struct globaldata *gd; 414 int n; 415 416 for (n = 0; n < ncpus; ++n) { 417 lwkt_setcpu_self(globaldata_find(n)); 418 gd = mycpu; 419 420 /* 421 * Use a non-queued periodic systimer to prevent multiple 422 * ticks from building up if the sysclock jumps forward 423 * (8254 gets reset). The sysclock will never jump backwards. 424 * Our time sync is based on the actual sysclock, not the 425 * ticks count. 426 * 427 * Install statclock before hardclock to prevent statclock 428 * from misinterpreting gd_flags for tick assignment when 429 * they overlap. Also offset the statclock by half of 430 * its interval to try to avoid being coincident with 431 * callouts. 432 */ 433 systimer_init_periodic_flags(&gd->gd_statclock, statclock, 434 NULL, stathz, 435 SYSTF_MSSYNC | SYSTF_FIRST | 436 SYSTF_OFFSET50 | SYSTF_OFFSETCPU); 437 systimer_init_periodic_flags(&gd->gd_hardclock, hardclock, 438 NULL, hz, 439 SYSTF_MSSYNC | SYSTF_OFFSETCPU); 440 } 441 lwkt_setcpu_self(ogd); 442 443 /* 444 * Regular data collection 445 */ 446 kcollect_register(KCOLLECT_USERPCT, "user", collect_cputime_callback, 447 KCOLLECT_SCALE(KCOLLECT_USERPCT_FORMAT, 0)); 448 kcollect_register(KCOLLECT_SYSTPCT, "syst", NULL, 449 KCOLLECT_SCALE(KCOLLECT_SYSTPCT_FORMAT, 0)); 450 kcollect_register(KCOLLECT_IDLEPCT, "idle", NULL, 451 KCOLLECT_SCALE(KCOLLECT_IDLEPCT_FORMAT, 0)); 452 } 453 SYSINIT(clocks2, SI_BOOT2_POST_SMP, SI_ORDER_ANY, initclocks_other, NULL); 454 455 /* 456 * This method is called on just the BSP, after all the usched implementations 457 * are initialized. This avoids races between usched initialization functions 458 * and usched_schedulerclock(). 459 */ 460 static 461 void 462 initclocks_usched(void *dummy) 463 { 464 struct globaldata *ogd = mycpu; 465 struct globaldata *gd; 466 int n; 467 468 for (n = 0; n < ncpus; ++n) { 469 lwkt_setcpu_self(globaldata_find(n)); 470 gd = mycpu; 471 472 /* XXX correct the frequency for scheduler / estcpu tests */ 473 systimer_init_periodic_flags(&gd->gd_schedclock, schedclock, 474 NULL, ESTCPUFREQ, SYSTF_MSSYNC); 475 } 476 lwkt_setcpu_self(ogd); 477 } 478 SYSINIT(clocks3, SI_BOOT2_USCHED, SI_ORDER_ANY, initclocks_usched, NULL); 479 480 /* 481 * This sets the current real time of day. Timespecs are in seconds and 482 * nanoseconds. We do not mess with gd_time_seconds and gd_cpuclock_base, 483 * instead we adjust basetime so basetime + gd_* results in the current 484 * time of day. This way the gd_* fields are guaranteed to represent 485 * a monotonically increasing 'uptime' value. 486 * 487 * When set_timeofday() is called from userland, the system call forces it 488 * onto cpu #0 since only cpu #0 can update basetime_index. 489 */ 490 void 491 set_timeofday(struct timespec *ts) 492 { 493 struct timespec *nbt; 494 int ni; 495 496 /* 497 * XXX SMP / non-atomic basetime updates 498 */ 499 crit_enter(); 500 ni = (basetime_index + 1) & BASETIME_ARYMASK; 501 cpu_lfence(); 502 nbt = &basetime[ni]; 503 nanouptime(nbt); 504 nbt->tv_sec = ts->tv_sec - nbt->tv_sec; 505 nbt->tv_nsec = ts->tv_nsec - nbt->tv_nsec; 506 if (nbt->tv_nsec < 0) { 507 nbt->tv_nsec += 1000000000; 508 --nbt->tv_sec; 509 } 510 511 /* 512 * Note that basetime diverges from boottime as the clock drift is 513 * compensated for, so we cannot do away with boottime. When setting 514 * the absolute time of day the drift is 0 (for an instant) and we 515 * can simply assign boottime to basetime. 516 * 517 * Note that nanouptime() is based on gd_time_seconds which is drift 518 * compensated up to a point (it is guaranteed to remain monotonically 519 * increasing). gd_time_seconds is thus our best uptime guess and 520 * suitable for use in the boottime calculation. It is already taken 521 * into account in the basetime calculation above. 522 */ 523 spin_lock(&ntp_spin); 524 boottime.tv_sec = nbt->tv_sec; 525 ntp_delta = 0; 526 527 /* 528 * We now have a new basetime, make sure all other cpus have it, 529 * then update the index. 530 */ 531 cpu_sfence(); 532 basetime_index = ni; 533 spin_unlock(&ntp_spin); 534 535 crit_exit(); 536 } 537 538 /* 539 * Each cpu has its own hardclock, but we only increment ticks and softticks 540 * on cpu #0. 541 * 542 * NOTE! systimer! the MP lock might not be held here. We can only safely 543 * manipulate objects owned by the current cpu. 544 */ 545 static void 546 hardclock(systimer_t info, int in_ipi, struct intrframe *frame) 547 { 548 sysclock_t cputicks; 549 struct proc *p; 550 struct globaldata *gd = mycpu; 551 552 if ((gd->gd_reqflags & RQF_IPIQ) == 0 && lwkt_need_ipiq_process(gd)) { 553 /* Defer to doreti on passive IPIQ processing */ 554 need_ipiq(); 555 } 556 557 /* 558 * We update the compensation base to calculate fine-grained time 559 * from the sys_cputimer on a per-cpu basis in order to avoid 560 * having to mess around with locks. sys_cputimer is assumed to 561 * be consistent across all cpus. CPU N copies the base state from 562 * CPU 0 using the same FIFO trick that we use for basetime (so we 563 * don't catch a CPU 0 update in the middle). 564 * 565 * Note that we never allow info->time (aka gd->gd_hardclock.time) 566 * to reverse index gd_cpuclock_base, but that it is possible for 567 * it to temporarily get behind in the seconds if something in the 568 * system locks interrupts for a long period of time. Since periodic 569 * timers count events, though everything should resynch again 570 * immediately. 571 */ 572 if (gd->gd_cpuid == 0) { 573 int ni; 574 575 cputicks = info->time - gd->gd_cpuclock_base; 576 if (cputicks >= sys_cputimer->freq) { 577 cputicks /= sys_cputimer->freq; 578 if (cputicks != 0 && cputicks != 1) 579 kprintf("Warning: hardclock missed > 1 sec\n"); 580 gd->gd_time_seconds += cputicks; 581 gd->gd_cpuclock_base += sys_cputimer->freq * cputicks; 582 /* uncorrected monotonic 1-sec gran */ 583 time_uptime += cputicks; 584 } 585 ni = (basetime_index + 1) & BASETIME_ARYMASK; 586 hardtime[ni].time_second = gd->gd_time_seconds; 587 hardtime[ni].cpuclock_base = gd->gd_cpuclock_base; 588 } else { 589 int ni; 590 591 ni = basetime_index; 592 cpu_lfence(); 593 gd->gd_time_seconds = hardtime[ni].time_second; 594 gd->gd_cpuclock_base = hardtime[ni].cpuclock_base; 595 } 596 597 /* 598 * The system-wide ticks counter and NTP related timedelta/tickdelta 599 * adjustments only occur on cpu #0. NTP adjustments are accomplished 600 * by updating basetime. 601 */ 602 if (gd->gd_cpuid == 0) { 603 struct timespec *nbt; 604 struct timespec nts; 605 int leap; 606 int ni; 607 608 /* 609 * Update system-wide ticks 610 */ 611 ++ticks; 612 613 /* 614 * Update system-wide ticktime for getnanotime() and getmicrotime() 615 */ 616 nanotime(&nts); 617 atomic_add_int_nonlocked(&ticktime_update, 1); 618 cpu_sfence(); 619 if (ticktime_update & 2) 620 ticktime2 = nts; 621 else 622 ticktime0 = nts; 623 cpu_sfence(); 624 atomic_add_int_nonlocked(&ticktime_update, 1); 625 626 #if 0 627 if (tco->tc_poll_pps) 628 tco->tc_poll_pps(tco); 629 #endif 630 631 /* 632 * Calculate the new basetime index. We are in a critical section 633 * on cpu #0 and can safely play with basetime_index. Start 634 * with the current basetime and then make adjustments. 635 */ 636 ni = (basetime_index + 1) & BASETIME_ARYMASK; 637 nbt = &basetime[ni]; 638 *nbt = basetime[basetime_index]; 639 640 /* 641 * ntp adjustments only occur on cpu 0 and are protected by 642 * ntp_spin. This spinlock virtually never conflicts. 643 */ 644 spin_lock(&ntp_spin); 645 646 /* 647 * Apply adjtime corrections. (adjtime() API) 648 * 649 * adjtime() only runs on cpu #0 so our critical section is 650 * sufficient to access these variables. 651 */ 652 if (ntp_delta != 0) { 653 nbt->tv_nsec += ntp_tick_delta; 654 ntp_delta -= ntp_tick_delta; 655 if ((ntp_delta > 0 && ntp_delta < ntp_tick_delta) || 656 (ntp_delta < 0 && ntp_delta > ntp_tick_delta)) { 657 ntp_tick_delta = ntp_delta; 658 } 659 } 660 661 /* 662 * Apply permanent frequency corrections. (sysctl API) 663 */ 664 if (ntp_tick_permanent != 0) { 665 ntp_tick_acc += ntp_tick_permanent; 666 if (ntp_tick_acc >= (1LL << 32)) { 667 nbt->tv_nsec += ntp_tick_acc >> 32; 668 ntp_tick_acc -= (ntp_tick_acc >> 32) << 32; 669 } else if (ntp_tick_acc <= -(1LL << 32)) { 670 /* Negate ntp_tick_acc to avoid shifting the sign bit. */ 671 nbt->tv_nsec -= (-ntp_tick_acc) >> 32; 672 ntp_tick_acc += ((-ntp_tick_acc) >> 32) << 32; 673 } 674 } 675 676 if (nbt->tv_nsec >= 1000000000) { 677 nbt->tv_sec++; 678 nbt->tv_nsec -= 1000000000; 679 } else if (nbt->tv_nsec < 0) { 680 nbt->tv_sec--; 681 nbt->tv_nsec += 1000000000; 682 } 683 684 /* 685 * Another per-tick compensation. (for ntp_adjtime() API) 686 */ 687 if (nsec_adj != 0) { 688 nsec_acc += nsec_adj; 689 if (nsec_acc >= 0x100000000LL) { 690 nbt->tv_nsec += nsec_acc >> 32; 691 nsec_acc = (nsec_acc & 0xFFFFFFFFLL); 692 } else if (nsec_acc <= -0x100000000LL) { 693 nbt->tv_nsec -= -nsec_acc >> 32; 694 nsec_acc = -(-nsec_acc & 0xFFFFFFFFLL); 695 } 696 if (nbt->tv_nsec >= 1000000000) { 697 nbt->tv_nsec -= 1000000000; 698 ++nbt->tv_sec; 699 } else if (nbt->tv_nsec < 0) { 700 nbt->tv_nsec += 1000000000; 701 --nbt->tv_sec; 702 } 703 } 704 spin_unlock(&ntp_spin); 705 706 /************************************************************ 707 * LEAP SECOND CORRECTION * 708 ************************************************************ 709 * 710 * Taking into account all the corrections made above, figure 711 * out the new real time. If the seconds field has changed 712 * then apply any pending leap-second corrections. 713 */ 714 getnanotime_nbt(nbt, &nts); 715 716 if (time_second != nts.tv_sec) { 717 /* 718 * Apply leap second (sysctl API). Adjust nts for changes 719 * so we do not have to call getnanotime_nbt again. 720 */ 721 if (ntp_leap_second) { 722 if (ntp_leap_second == nts.tv_sec) { 723 if (ntp_leap_insert) { 724 nbt->tv_sec++; 725 nts.tv_sec++; 726 } else { 727 nbt->tv_sec--; 728 nts.tv_sec--; 729 } 730 ntp_leap_second--; 731 } 732 } 733 734 /* 735 * Apply leap second (ntp_adjtime() API), calculate a new 736 * nsec_adj field. ntp_update_second() returns nsec_adj 737 * as a per-second value but we need it as a per-tick value. 738 */ 739 leap = ntp_update_second(time_second, &nsec_adj); 740 nsec_adj /= hz; 741 nbt->tv_sec += leap; 742 nts.tv_sec += leap; 743 744 /* 745 * Update the time_second 'approximate time' global. 746 */ 747 time_second = nts.tv_sec; 748 749 /* 750 * Clear the IPC hint for the currently running thread once 751 * per second, allowing us to disconnect the hint from a 752 * thread which may no longer care. 753 */ 754 curthread->td_wakefromcpu = -1; 755 } 756 757 /* 758 * Finally, our new basetime is ready to go live! 759 */ 760 cpu_sfence(); 761 basetime_index = ni; 762 763 /* 764 * Update kpmap on each tick. TS updates are integrated with 765 * fences and upticks allowing userland to read the data 766 * deterministically. 767 */ 768 if (kpmap) { 769 int w; 770 771 w = (kpmap->upticks + 1) & 1; 772 getnanouptime(&kpmap->ts_uptime[w]); 773 getnanotime(&kpmap->ts_realtime[w]); 774 cpu_sfence(); 775 ++kpmap->upticks; 776 cpu_sfence(); 777 } 778 } 779 780 /* 781 * lwkt thread scheduler fair queueing 782 */ 783 lwkt_schedulerclock(curthread); 784 785 /* 786 * softticks are handled for all cpus 787 */ 788 hardclock_softtick(gd); 789 790 /* 791 * Rollup accumulated vmstats, copy-back for critical path checks. 792 */ 793 vmstats_rollup_cpu(gd); 794 vfscache_rollup_cpu(gd); 795 mycpu->gd_vmstats = vmstats; 796 797 /* 798 * ITimer handling is per-tick, per-cpu. 799 * 800 * We must acquire the per-process token in order for ksignal() 801 * to be non-blocking. For the moment this requires an AST fault, 802 * the ksignal() cannot be safely issued from this hard interrupt. 803 * 804 * XXX Even the trytoken here isn't right, and itimer operation in 805 * a multi threaded environment is going to be weird at the 806 * very least. 807 */ 808 if ((p = curproc) != NULL && lwkt_trytoken(&p->p_token)) { 809 crit_enter_hard(); 810 if (p->p_upmap) 811 ++p->p_upmap->runticks; 812 813 if (frame && CLKF_USERMODE(frame) && 814 timevalisset(&p->p_timer[ITIMER_VIRTUAL].it_value) && 815 itimerdecr(&p->p_timer[ITIMER_VIRTUAL], ustick) == 0) { 816 p->p_flags |= P_SIGVTALRM; 817 need_user_resched(); 818 } 819 if (timevalisset(&p->p_timer[ITIMER_PROF].it_value) && 820 itimerdecr(&p->p_timer[ITIMER_PROF], ustick) == 0) { 821 p->p_flags |= P_SIGPROF; 822 need_user_resched(); 823 } 824 crit_exit_hard(); 825 lwkt_reltoken(&p->p_token); 826 } 827 setdelayed(); 828 } 829 830 /* 831 * The statistics clock typically runs at a 125Hz rate, and is intended 832 * to be frequency offset from the hardclock (typ 100Hz). It is per-cpu. 833 * 834 * NOTE! systimer! the MP lock might not be held here. We can only safely 835 * manipulate objects owned by the current cpu. 836 * 837 * The stats clock is responsible for grabbing a profiling sample. 838 * Most of the statistics are only used by user-level statistics programs. 839 * The main exceptions are p->p_uticks, p->p_sticks, p->p_iticks, and 840 * p->p_estcpu. 841 * 842 * Like the other clocks, the stat clock is called from what is effectively 843 * a fast interrupt, so the context should be the thread/process that got 844 * interrupted. 845 */ 846 static void 847 statclock(systimer_t info, int in_ipi, struct intrframe *frame) 848 { 849 globaldata_t gd = mycpu; 850 thread_t td; 851 struct proc *p; 852 int bump; 853 sysclock_t cv; 854 sysclock_t scv; 855 856 /* 857 * How big was our timeslice relative to the last time? Calculate 858 * in microseconds. 859 * 860 * NOTE: Use of microuptime() is typically MPSAFE, but usually not 861 * during early boot. Just use the systimer count to be nice 862 * to e.g. qemu. The systimer has a better chance of being 863 * MPSAFE at early boot. 864 */ 865 cv = sys_cputimer->count(); 866 scv = gd->statint.gd_statcv; 867 if (scv == 0) { 868 bump = 1; 869 } else { 870 bump = (sys_cputimer->freq64_usec * (cv - scv)) >> 32; 871 if (bump < 0) 872 bump = 0; 873 if (bump > 1000000) 874 bump = 1000000; 875 } 876 gd->statint.gd_statcv = cv; 877 878 #if 0 879 stv = &gd->gd_stattv; 880 if (stv->tv_sec == 0) { 881 bump = 1; 882 } else { 883 bump = tv.tv_usec - stv->tv_usec + 884 (tv.tv_sec - stv->tv_sec) * 1000000; 885 if (bump < 0) 886 bump = 0; 887 if (bump > 1000000) 888 bump = 1000000; 889 } 890 *stv = tv; 891 #endif 892 893 td = curthread; 894 p = td->td_proc; 895 896 /* 897 * If this is an interrupt thread used for the clock interrupt, adjust 898 * td to the thread it is preempting. If a frame is available, it will 899 * be related to the thread being preempted. 900 */ 901 if ((td->td_flags & TDF_CLKTHREAD) && td->td_preempted) 902 td = td->td_preempted; 903 904 if (frame && CLKF_USERMODE(frame)) { 905 /* 906 * Came from userland, handle user time and deal with 907 * possible process. 908 */ 909 if (p && (p->p_flags & P_PROFIL)) 910 addupc_intr(p, CLKF_PC(frame), 1); 911 td->td_uticks += bump; 912 913 /* 914 * Charge the time as appropriate 915 */ 916 if (p && p->p_nice > NZERO) 917 cpu_time.cp_nice += bump; 918 else 919 cpu_time.cp_user += bump; 920 } else { 921 int intr_nest = gd->gd_intr_nesting_level; 922 923 if (in_ipi) { 924 /* 925 * IPI processing code will bump gd_intr_nesting_level 926 * up by one, which breaks following CLKF_INTR testing, 927 * so we subtract it by one here. 928 */ 929 --intr_nest; 930 } 931 932 /* 933 * Came from kernel mode, so we were: 934 * - handling an interrupt, 935 * - doing syscall or trap work on behalf of the current 936 * user process, or 937 * - spinning in the idle loop. 938 * Whichever it is, charge the time as appropriate. 939 * Note that we charge interrupts to the current process, 940 * regardless of whether they are ``for'' that process, 941 * so that we know how much of its real time was spent 942 * in ``non-process'' (i.e., interrupt) work. 943 * 944 * XXX assume system if frame is NULL. A NULL frame 945 * can occur if ipi processing is done from a crit_exit(). 946 */ 947 if ((frame && CLKF_INTR(intr_nest)) || 948 cpu_interrupt_running(td)) { 949 /* 950 * If we interrupted an interrupt thread, well, 951 * count it as interrupt time. 952 */ 953 td->td_iticks += bump; 954 #ifdef DEBUG_PCTRACK 955 if (frame) 956 do_pctrack(frame, PCTRACK_INT); 957 #endif 958 cpu_time.cp_intr += bump; 959 } else if (gd->gd_flags & GDF_VIRTUSER) { 960 /* 961 * The vkernel doesn't do a good job providing trap 962 * frames that we can test. If the GDF_VIRTUSER 963 * flag is set we probably interrupted user mode. 964 * 965 * We also use this flag on the host when entering 966 * VMM mode. 967 */ 968 td->td_uticks += bump; 969 970 /* 971 * Charge the time as appropriate 972 */ 973 if (p && p->p_nice > NZERO) 974 cpu_time.cp_nice += bump; 975 else 976 cpu_time.cp_user += bump; 977 } else { 978 if (clock_debug2 > 0) { 979 --clock_debug2; 980 kprintf("statclock preempt %s (%p %p)\n", td->td_comm, td, &gd->gd_idlethread); 981 } 982 td->td_sticks += bump; 983 if (td == &gd->gd_idlethread) { 984 /* 985 * We want to count token contention as 986 * system time. When token contention occurs 987 * the cpu may only be outside its critical 988 * section while switching through the idle 989 * thread. In this situation, various flags 990 * will be set in gd_reqflags. 991 * 992 * INTPEND is not necessarily useful because 993 * it will be set if the clock interrupt 994 * happens to be on an interrupt thread, the 995 * cpu_interrupt_running() call does a better 996 * job so we've already handled it. 997 */ 998 if (gd->gd_reqflags & 999 (RQF_IDLECHECK_WK_MASK & ~RQF_INTPEND)) { 1000 cpu_time.cp_sys += bump; 1001 } else { 1002 cpu_time.cp_idle += bump; 1003 } 1004 } else { 1005 /* 1006 * System thread was running. 1007 */ 1008 #ifdef DEBUG_PCTRACK 1009 if (frame) 1010 do_pctrack(frame, PCTRACK_SYS); 1011 #endif 1012 cpu_time.cp_sys += bump; 1013 } 1014 } 1015 } 1016 } 1017 1018 #ifdef DEBUG_PCTRACK 1019 /* 1020 * Sample the PC when in the kernel or in an interrupt. User code can 1021 * retrieve the information and generate a histogram or other output. 1022 */ 1023 1024 static void 1025 do_pctrack(struct intrframe *frame, int which) 1026 { 1027 struct kinfo_pctrack *pctrack; 1028 1029 pctrack = &cputime_pctrack[mycpu->gd_cpuid][which]; 1030 pctrack->pc_array[pctrack->pc_index & PCTRACK_ARYMASK] = 1031 (void *)CLKF_PC(frame); 1032 ++pctrack->pc_index; 1033 } 1034 1035 static int 1036 sysctl_pctrack(SYSCTL_HANDLER_ARGS) 1037 { 1038 struct kinfo_pcheader head; 1039 int error; 1040 int cpu; 1041 int ntrack; 1042 1043 head.pc_ntrack = PCTRACK_SIZE; 1044 head.pc_arysize = PCTRACK_ARYSIZE; 1045 1046 if ((error = SYSCTL_OUT(req, &head, sizeof(head))) != 0) 1047 return (error); 1048 1049 for (cpu = 0; cpu < ncpus; ++cpu) { 1050 for (ntrack = 0; ntrack < PCTRACK_SIZE; ++ntrack) { 1051 error = SYSCTL_OUT(req, &cputime_pctrack[cpu][ntrack], 1052 sizeof(struct kinfo_pctrack)); 1053 if (error) 1054 break; 1055 } 1056 if (error) 1057 break; 1058 } 1059 return (error); 1060 } 1061 SYSCTL_PROC(_kern, OID_AUTO, pctrack, (CTLTYPE_OPAQUE|CTLFLAG_RD), 0, 0, 1062 sysctl_pctrack, "S,kinfo_pcheader", "CPU PC tracking"); 1063 1064 #endif 1065 1066 /* 1067 * The scheduler clock typically runs at a 50Hz rate. NOTE! systimer, 1068 * the MP lock might not be held. We can safely manipulate parts of curproc 1069 * but that's about it. 1070 * 1071 * Each cpu has its own scheduler clock. 1072 */ 1073 static void 1074 schedclock(systimer_t info, int in_ipi __unused, struct intrframe *frame) 1075 { 1076 struct lwp *lp; 1077 struct rusage *ru; 1078 struct vmspace *vm; 1079 long rss; 1080 1081 if ((lp = lwkt_preempted_proc()) != NULL) { 1082 /* 1083 * Account for cpu time used and hit the scheduler. Note 1084 * that this call MUST BE MP SAFE, and the BGL IS NOT HELD 1085 * HERE. 1086 */ 1087 ++lp->lwp_cpticks; 1088 usched_schedulerclock(lp, info->periodic, info->time); 1089 } else { 1090 usched_schedulerclock(NULL, info->periodic, info->time); 1091 } 1092 if ((lp = curthread->td_lwp) != NULL) { 1093 /* 1094 * Update resource usage integrals and maximums. 1095 */ 1096 if ((ru = &lp->lwp_proc->p_ru) && 1097 (vm = lp->lwp_proc->p_vmspace) != NULL) { 1098 ru->ru_ixrss += pgtok(btoc(vm->vm_tsize)); 1099 ru->ru_idrss += pgtok(btoc(vm->vm_dsize)); 1100 ru->ru_isrss += pgtok(btoc(vm->vm_ssize)); 1101 if (lwkt_trytoken(&vm->vm_map.token)) { 1102 rss = pgtok(vmspace_resident_count(vm)); 1103 if (ru->ru_maxrss < rss) 1104 ru->ru_maxrss = rss; 1105 lwkt_reltoken(&vm->vm_map.token); 1106 } 1107 } 1108 } 1109 /* Increment the global sched_ticks */ 1110 if (mycpu->gd_cpuid == 0) 1111 ++sched_ticks; 1112 } 1113 1114 /* 1115 * Compute number of ticks for the specified amount of time. The 1116 * return value is intended to be used in a clock interrupt timed 1117 * operation and guaranteed to meet or exceed the requested time. 1118 * If the representation overflows, return INT_MAX. The minimum return 1119 * value is 1 ticks and the function will average the calculation up. 1120 * If any value greater then 0 microseconds is supplied, a value 1121 * of at least 2 will be returned to ensure that a near-term clock 1122 * interrupt does not cause the timeout to occur (degenerately) early. 1123 * 1124 * Note that limit checks must take into account microseconds, which is 1125 * done simply by using the smaller signed long maximum instead of 1126 * the unsigned long maximum. 1127 * 1128 * If ints have 32 bits, then the maximum value for any timeout in 1129 * 10ms ticks is 248 days. 1130 */ 1131 int 1132 tvtohz_high(struct timeval *tv) 1133 { 1134 int ticks; 1135 long sec, usec; 1136 1137 sec = tv->tv_sec; 1138 usec = tv->tv_usec; 1139 if (usec < 0) { 1140 sec--; 1141 usec += 1000000; 1142 } 1143 if (sec < 0) { 1144 #ifdef DIAGNOSTIC 1145 if (usec > 0) { 1146 sec++; 1147 usec -= 1000000; 1148 } 1149 kprintf("tvtohz_high: negative time difference " 1150 "%ld sec %ld usec\n", 1151 sec, usec); 1152 #endif 1153 ticks = 1; 1154 } else if (sec <= INT_MAX / hz) { 1155 ticks = (int)(sec * hz + howmany((u_long)usec, ustick)) + 1; 1156 } else { 1157 ticks = INT_MAX; 1158 } 1159 return (ticks); 1160 } 1161 1162 int 1163 tstohz_high(struct timespec *ts) 1164 { 1165 int ticks; 1166 long sec, nsec; 1167 1168 sec = ts->tv_sec; 1169 nsec = ts->tv_nsec; 1170 if (nsec < 0) { 1171 sec--; 1172 nsec += 1000000000; 1173 } 1174 if (sec < 0) { 1175 #ifdef DIAGNOSTIC 1176 if (nsec > 0) { 1177 sec++; 1178 nsec -= 1000000000; 1179 } 1180 kprintf("tstohz_high: negative time difference " 1181 "%ld sec %ld nsec\n", 1182 sec, nsec); 1183 #endif 1184 ticks = 1; 1185 } else if (sec <= INT_MAX / hz) { 1186 ticks = (int)(sec * hz + howmany((u_long)nsec, nstick)) + 1; 1187 } else { 1188 ticks = INT_MAX; 1189 } 1190 return (ticks); 1191 } 1192 1193 1194 /* 1195 * Compute number of ticks for the specified amount of time, erroring on 1196 * the side of it being too low to ensure that sleeping the returned number 1197 * of ticks will not result in a late return. 1198 * 1199 * The supplied timeval may not be negative and should be normalized. A 1200 * return value of 0 is possible if the timeval converts to less then 1201 * 1 tick. 1202 * 1203 * If ints have 32 bits, then the maximum value for any timeout in 1204 * 10ms ticks is 248 days. 1205 */ 1206 int 1207 tvtohz_low(struct timeval *tv) 1208 { 1209 int ticks; 1210 long sec; 1211 1212 sec = tv->tv_sec; 1213 if (sec <= INT_MAX / hz) 1214 ticks = (int)(sec * hz + (u_long)tv->tv_usec / ustick); 1215 else 1216 ticks = INT_MAX; 1217 return (ticks); 1218 } 1219 1220 int 1221 tstohz_low(struct timespec *ts) 1222 { 1223 int ticks; 1224 long sec; 1225 1226 sec = ts->tv_sec; 1227 if (sec <= INT_MAX / hz) 1228 ticks = (int)(sec * hz + (u_long)ts->tv_nsec / nstick); 1229 else 1230 ticks = INT_MAX; 1231 return (ticks); 1232 } 1233 1234 /* 1235 * Start profiling on a process. 1236 * 1237 * Caller must hold p->p_token(); 1238 * 1239 * Kernel profiling passes proc0 which never exits and hence 1240 * keeps the profile clock running constantly. 1241 */ 1242 void 1243 startprofclock(struct proc *p) 1244 { 1245 if ((p->p_flags & P_PROFIL) == 0) { 1246 p->p_flags |= P_PROFIL; 1247 #if 0 /* XXX */ 1248 if (++profprocs == 1 && stathz != 0) { 1249 crit_enter(); 1250 psdiv = psratio; 1251 setstatclockrate(profhz); 1252 crit_exit(); 1253 } 1254 #endif 1255 } 1256 } 1257 1258 /* 1259 * Stop profiling on a process. 1260 * 1261 * caller must hold p->p_token 1262 */ 1263 void 1264 stopprofclock(struct proc *p) 1265 { 1266 if (p->p_flags & P_PROFIL) { 1267 p->p_flags &= ~P_PROFIL; 1268 #if 0 /* XXX */ 1269 if (--profprocs == 0 && stathz != 0) { 1270 crit_enter(); 1271 psdiv = 1; 1272 setstatclockrate(stathz); 1273 crit_exit(); 1274 } 1275 #endif 1276 } 1277 } 1278 1279 /* 1280 * Return information about system clocks. 1281 */ 1282 static int 1283 sysctl_kern_clockrate(SYSCTL_HANDLER_ARGS) 1284 { 1285 struct kinfo_clockinfo clkinfo; 1286 /* 1287 * Construct clockinfo structure. 1288 */ 1289 clkinfo.ci_hz = hz; 1290 clkinfo.ci_tick = ustick; 1291 clkinfo.ci_tickadj = ntp_default_tick_delta / 1000; 1292 clkinfo.ci_profhz = profhz; 1293 clkinfo.ci_stathz = stathz ? stathz : hz; 1294 return (sysctl_handle_opaque(oidp, &clkinfo, sizeof clkinfo, req)); 1295 } 1296 1297 SYSCTL_PROC(_kern, KERN_CLOCKRATE, clockrate, CTLTYPE_STRUCT|CTLFLAG_RD, 1298 0, 0, sysctl_kern_clockrate, "S,clockinfo",""); 1299 1300 /* 1301 * We have eight functions for looking at the clock, four for 1302 * microseconds and four for nanoseconds. For each there is fast 1303 * but less precise version "get{nano|micro}[up]time" which will 1304 * return a time which is up to 1/HZ previous to the call, whereas 1305 * the raw version "{nano|micro}[up]time" will return a timestamp 1306 * which is as precise as possible. The "up" variants return the 1307 * time relative to system boot, these are well suited for time 1308 * interval measurements. 1309 * 1310 * Each cpu independently maintains the current time of day, so all 1311 * we need to do to protect ourselves from changes is to do a loop 1312 * check on the seconds field changing out from under us. 1313 * 1314 * The system timer maintains a 32 bit count and due to various issues 1315 * it is possible for the calculated delta to occasionally exceed 1316 * sys_cputimer->freq. If this occurs the sys_cputimer->freq64_nsec 1317 * multiplication can easily overflow, so we deal with the case. For 1318 * uniformity we deal with the case in the usec case too. 1319 * 1320 * All the [get][micro,nano][time,uptime]() routines are MPSAFE. 1321 * 1322 * NEW CODE (!) 1323 * 1324 * cpu 0 now maintains global ticktimes and an update counter. The 1325 * getnanotime() and getmicrotime() routines use these globals. 1326 */ 1327 void 1328 getmicrouptime(struct timeval *tvp) 1329 { 1330 struct globaldata *gd = mycpu; 1331 sysclock_t delta; 1332 1333 do { 1334 tvp->tv_sec = gd->gd_time_seconds; 1335 delta = gd->gd_hardclock.time - gd->gd_cpuclock_base; 1336 } while (tvp->tv_sec != gd->gd_time_seconds); 1337 1338 if (delta >= sys_cputimer->freq) { 1339 tvp->tv_sec += delta / sys_cputimer->freq; 1340 delta %= sys_cputimer->freq; 1341 } 1342 tvp->tv_usec = (sys_cputimer->freq64_usec * delta) >> 32; 1343 if (tvp->tv_usec >= 1000000) { 1344 tvp->tv_usec -= 1000000; 1345 ++tvp->tv_sec; 1346 } 1347 } 1348 1349 void 1350 getnanouptime(struct timespec *tsp) 1351 { 1352 struct globaldata *gd = mycpu; 1353 sysclock_t delta; 1354 1355 do { 1356 tsp->tv_sec = gd->gd_time_seconds; 1357 delta = gd->gd_hardclock.time - gd->gd_cpuclock_base; 1358 } while (tsp->tv_sec != gd->gd_time_seconds); 1359 1360 if (delta >= sys_cputimer->freq) { 1361 tsp->tv_sec += delta / sys_cputimer->freq; 1362 delta %= sys_cputimer->freq; 1363 } 1364 tsp->tv_nsec = (sys_cputimer->freq64_nsec * delta) >> 32; 1365 } 1366 1367 void 1368 microuptime(struct timeval *tvp) 1369 { 1370 struct globaldata *gd = mycpu; 1371 sysclock_t delta; 1372 1373 do { 1374 tvp->tv_sec = gd->gd_time_seconds; 1375 delta = sys_cputimer->count() - gd->gd_cpuclock_base; 1376 } while (tvp->tv_sec != gd->gd_time_seconds); 1377 1378 if (delta >= sys_cputimer->freq) { 1379 tvp->tv_sec += delta / sys_cputimer->freq; 1380 delta %= sys_cputimer->freq; 1381 } 1382 tvp->tv_usec = (sys_cputimer->freq64_usec * delta) >> 32; 1383 } 1384 1385 void 1386 nanouptime(struct timespec *tsp) 1387 { 1388 struct globaldata *gd = mycpu; 1389 sysclock_t delta; 1390 1391 do { 1392 tsp->tv_sec = gd->gd_time_seconds; 1393 delta = sys_cputimer->count() - gd->gd_cpuclock_base; 1394 } while (tsp->tv_sec != gd->gd_time_seconds); 1395 1396 if (delta >= sys_cputimer->freq) { 1397 tsp->tv_sec += delta / sys_cputimer->freq; 1398 delta %= sys_cputimer->freq; 1399 } 1400 tsp->tv_nsec = (sys_cputimer->freq64_nsec * delta) >> 32; 1401 } 1402 1403 /* 1404 * realtime routines 1405 */ 1406 void 1407 getmicrotime(struct timeval *tvp) 1408 { 1409 struct timespec ts; 1410 int counter; 1411 1412 do { 1413 counter = *(volatile int *)&ticktime_update; 1414 cpu_lfence(); 1415 switch(counter & 3) { 1416 case 0: /* ticktime2 completed update */ 1417 ts = ticktime2; 1418 break; 1419 case 1: /* ticktime0 update in progress */ 1420 ts = ticktime2; 1421 break; 1422 case 2: /* ticktime0 completed update */ 1423 ts = ticktime0; 1424 break; 1425 case 3: /* ticktime2 update in progress */ 1426 ts = ticktime0; 1427 break; 1428 } 1429 cpu_lfence(); 1430 } while (counter != *(volatile int *)&ticktime_update); 1431 tvp->tv_sec = ts.tv_sec; 1432 tvp->tv_usec = ts.tv_nsec / 1000; 1433 } 1434 1435 void 1436 getnanotime(struct timespec *tsp) 1437 { 1438 struct timespec ts; 1439 int counter; 1440 1441 do { 1442 counter = *(volatile int *)&ticktime_update; 1443 cpu_lfence(); 1444 switch(counter & 3) { 1445 case 0: /* ticktime2 completed update */ 1446 ts = ticktime2; 1447 break; 1448 case 1: /* ticktime0 update in progress */ 1449 ts = ticktime2; 1450 break; 1451 case 2: /* ticktime0 completed update */ 1452 ts = ticktime0; 1453 break; 1454 case 3: /* ticktime2 update in progress */ 1455 ts = ticktime0; 1456 break; 1457 } 1458 cpu_lfence(); 1459 } while (counter != *(volatile int *)&ticktime_update); 1460 *tsp = ts; 1461 } 1462 1463 static void 1464 getnanotime_nbt(struct timespec *nbt, struct timespec *tsp) 1465 { 1466 struct globaldata *gd = mycpu; 1467 sysclock_t delta; 1468 1469 do { 1470 tsp->tv_sec = gd->gd_time_seconds; 1471 delta = gd->gd_hardclock.time - gd->gd_cpuclock_base; 1472 } while (tsp->tv_sec != gd->gd_time_seconds); 1473 1474 if (delta >= sys_cputimer->freq) { 1475 tsp->tv_sec += delta / sys_cputimer->freq; 1476 delta %= sys_cputimer->freq; 1477 } 1478 tsp->tv_nsec = (sys_cputimer->freq64_nsec * delta) >> 32; 1479 1480 tsp->tv_sec += nbt->tv_sec; 1481 tsp->tv_nsec += nbt->tv_nsec; 1482 while (tsp->tv_nsec >= 1000000000) { 1483 tsp->tv_nsec -= 1000000000; 1484 ++tsp->tv_sec; 1485 } 1486 } 1487 1488 1489 void 1490 microtime(struct timeval *tvp) 1491 { 1492 struct globaldata *gd = mycpu; 1493 struct timespec *bt; 1494 sysclock_t delta; 1495 1496 do { 1497 tvp->tv_sec = gd->gd_time_seconds; 1498 delta = sys_cputimer->count() - gd->gd_cpuclock_base; 1499 } while (tvp->tv_sec != gd->gd_time_seconds); 1500 1501 if (delta >= sys_cputimer->freq) { 1502 tvp->tv_sec += delta / sys_cputimer->freq; 1503 delta %= sys_cputimer->freq; 1504 } 1505 tvp->tv_usec = (sys_cputimer->freq64_usec * delta) >> 32; 1506 1507 bt = &basetime[basetime_index]; 1508 cpu_lfence(); 1509 tvp->tv_sec += bt->tv_sec; 1510 tvp->tv_usec += bt->tv_nsec / 1000; 1511 while (tvp->tv_usec >= 1000000) { 1512 tvp->tv_usec -= 1000000; 1513 ++tvp->tv_sec; 1514 } 1515 } 1516 1517 void 1518 nanotime(struct timespec *tsp) 1519 { 1520 struct globaldata *gd = mycpu; 1521 struct timespec *bt; 1522 sysclock_t delta; 1523 1524 do { 1525 tsp->tv_sec = gd->gd_time_seconds; 1526 delta = sys_cputimer->count() - gd->gd_cpuclock_base; 1527 } while (tsp->tv_sec != gd->gd_time_seconds); 1528 1529 if (delta >= sys_cputimer->freq) { 1530 tsp->tv_sec += delta / sys_cputimer->freq; 1531 delta %= sys_cputimer->freq; 1532 } 1533 tsp->tv_nsec = (sys_cputimer->freq64_nsec * delta) >> 32; 1534 1535 bt = &basetime[basetime_index]; 1536 cpu_lfence(); 1537 tsp->tv_sec += bt->tv_sec; 1538 tsp->tv_nsec += bt->tv_nsec; 1539 while (tsp->tv_nsec >= 1000000000) { 1540 tsp->tv_nsec -= 1000000000; 1541 ++tsp->tv_sec; 1542 } 1543 } 1544 1545 /* 1546 * Get an approximate time_t. It does not have to be accurate. This 1547 * function is called only from KTR and can be called with the system in 1548 * any state so do not use a critical section or other complex operation 1549 * here. 1550 * 1551 * NOTE: This is not exactly synchronized with real time. To do that we 1552 * would have to do what microtime does and check for a nanoseconds 1553 * overflow. 1554 */ 1555 time_t 1556 get_approximate_time_t(void) 1557 { 1558 struct globaldata *gd = mycpu; 1559 struct timespec *bt; 1560 1561 bt = &basetime[basetime_index]; 1562 return(gd->gd_time_seconds + bt->tv_sec); 1563 } 1564 1565 int 1566 pps_ioctl(u_long cmd, caddr_t data, struct pps_state *pps) 1567 { 1568 pps_params_t *app; 1569 struct pps_fetch_args *fapi; 1570 #ifdef PPS_SYNC 1571 struct pps_kcbind_args *kapi; 1572 #endif 1573 1574 switch (cmd) { 1575 case PPS_IOC_CREATE: 1576 return (0); 1577 case PPS_IOC_DESTROY: 1578 return (0); 1579 case PPS_IOC_SETPARAMS: 1580 app = (pps_params_t *)data; 1581 if (app->mode & ~pps->ppscap) 1582 return (EINVAL); 1583 pps->ppsparam = *app; 1584 return (0); 1585 case PPS_IOC_GETPARAMS: 1586 app = (pps_params_t *)data; 1587 *app = pps->ppsparam; 1588 app->api_version = PPS_API_VERS_1; 1589 return (0); 1590 case PPS_IOC_GETCAP: 1591 *(int*)data = pps->ppscap; 1592 return (0); 1593 case PPS_IOC_FETCH: 1594 fapi = (struct pps_fetch_args *)data; 1595 if (fapi->tsformat && fapi->tsformat != PPS_TSFMT_TSPEC) 1596 return (EINVAL); 1597 if (fapi->timeout.tv_sec || fapi->timeout.tv_nsec) 1598 return (EOPNOTSUPP); 1599 pps->ppsinfo.current_mode = pps->ppsparam.mode; 1600 fapi->pps_info_buf = pps->ppsinfo; 1601 return (0); 1602 case PPS_IOC_KCBIND: 1603 #ifdef PPS_SYNC 1604 kapi = (struct pps_kcbind_args *)data; 1605 /* XXX Only root should be able to do this */ 1606 if (kapi->tsformat && kapi->tsformat != PPS_TSFMT_TSPEC) 1607 return (EINVAL); 1608 if (kapi->kernel_consumer != PPS_KC_HARDPPS) 1609 return (EINVAL); 1610 if (kapi->edge & ~pps->ppscap) 1611 return (EINVAL); 1612 pps->kcmode = kapi->edge; 1613 return (0); 1614 #else 1615 return (EOPNOTSUPP); 1616 #endif 1617 default: 1618 return (ENOTTY); 1619 } 1620 } 1621 1622 void 1623 pps_init(struct pps_state *pps) 1624 { 1625 pps->ppscap |= PPS_TSFMT_TSPEC; 1626 if (pps->ppscap & PPS_CAPTUREASSERT) 1627 pps->ppscap |= PPS_OFFSETASSERT; 1628 if (pps->ppscap & PPS_CAPTURECLEAR) 1629 pps->ppscap |= PPS_OFFSETCLEAR; 1630 } 1631 1632 void 1633 pps_event(struct pps_state *pps, sysclock_t count, int event) 1634 { 1635 struct globaldata *gd; 1636 struct timespec *tsp; 1637 struct timespec *osp; 1638 struct timespec *bt; 1639 struct timespec ts; 1640 sysclock_t *pcount; 1641 #ifdef PPS_SYNC 1642 sysclock_t tcount; 1643 #endif 1644 sysclock_t delta; 1645 pps_seq_t *pseq; 1646 int foff; 1647 #ifdef PPS_SYNC 1648 int fhard; 1649 #endif 1650 int ni; 1651 1652 gd = mycpu; 1653 1654 /* Things would be easier with arrays... */ 1655 if (event == PPS_CAPTUREASSERT) { 1656 tsp = &pps->ppsinfo.assert_timestamp; 1657 osp = &pps->ppsparam.assert_offset; 1658 foff = pps->ppsparam.mode & PPS_OFFSETASSERT; 1659 #ifdef PPS_SYNC 1660 fhard = pps->kcmode & PPS_CAPTUREASSERT; 1661 #endif 1662 pcount = &pps->ppscount[0]; 1663 pseq = &pps->ppsinfo.assert_sequence; 1664 } else { 1665 tsp = &pps->ppsinfo.clear_timestamp; 1666 osp = &pps->ppsparam.clear_offset; 1667 foff = pps->ppsparam.mode & PPS_OFFSETCLEAR; 1668 #ifdef PPS_SYNC 1669 fhard = pps->kcmode & PPS_CAPTURECLEAR; 1670 #endif 1671 pcount = &pps->ppscount[1]; 1672 pseq = &pps->ppsinfo.clear_sequence; 1673 } 1674 1675 /* Nothing really happened */ 1676 if (*pcount == count) 1677 return; 1678 1679 *pcount = count; 1680 1681 do { 1682 ts.tv_sec = gd->gd_time_seconds; 1683 delta = count - gd->gd_cpuclock_base; 1684 } while (ts.tv_sec != gd->gd_time_seconds); 1685 1686 if (delta >= sys_cputimer->freq) { 1687 ts.tv_sec += delta / sys_cputimer->freq; 1688 delta %= sys_cputimer->freq; 1689 } 1690 ts.tv_nsec = (sys_cputimer->freq64_nsec * delta) >> 32; 1691 ni = basetime_index; 1692 cpu_lfence(); 1693 bt = &basetime[ni]; 1694 ts.tv_sec += bt->tv_sec; 1695 ts.tv_nsec += bt->tv_nsec; 1696 while (ts.tv_nsec >= 1000000000) { 1697 ts.tv_nsec -= 1000000000; 1698 ++ts.tv_sec; 1699 } 1700 1701 (*pseq)++; 1702 *tsp = ts; 1703 1704 if (foff) { 1705 timespecadd(tsp, osp, tsp); 1706 if (tsp->tv_nsec < 0) { 1707 tsp->tv_nsec += 1000000000; 1708 tsp->tv_sec -= 1; 1709 } 1710 } 1711 #ifdef PPS_SYNC 1712 if (fhard) { 1713 /* magic, at its best... */ 1714 tcount = count - pps->ppscount[2]; 1715 pps->ppscount[2] = count; 1716 if (tcount >= sys_cputimer->freq) { 1717 delta = (1000000000 * (tcount / sys_cputimer->freq) + 1718 sys_cputimer->freq64_nsec * 1719 (tcount % sys_cputimer->freq)) >> 32; 1720 } else { 1721 delta = (sys_cputimer->freq64_nsec * tcount) >> 32; 1722 } 1723 hardpps(tsp, delta); 1724 } 1725 #endif 1726 } 1727 1728 /* 1729 * Return the tsc target value for a delay of (ns). 1730 * 1731 * Returns -1 if the TSC is not supported. 1732 */ 1733 tsc_uclock_t 1734 tsc_get_target(int ns) 1735 { 1736 #if defined(_RDTSC_SUPPORTED_) 1737 if (cpu_feature & CPUID_TSC) { 1738 return (rdtsc() + tsc_frequency * ns / (int64_t)1000000000); 1739 } 1740 #endif 1741 return(-1); 1742 } 1743 1744 /* 1745 * Compare the tsc against the passed target 1746 * 1747 * Returns +1 if the target has been reached 1748 * Returns 0 if the target has not yet been reached 1749 * Returns -1 if the TSC is not supported. 1750 * 1751 * Typical use: while (tsc_test_target(target) == 0) { ...poll... } 1752 */ 1753 int 1754 tsc_test_target(int64_t target) 1755 { 1756 #if defined(_RDTSC_SUPPORTED_) 1757 if (cpu_feature & CPUID_TSC) { 1758 if ((int64_t)(target - rdtsc()) <= 0) 1759 return(1); 1760 return(0); 1761 } 1762 #endif 1763 return(-1); 1764 } 1765 1766 /* 1767 * Delay the specified number of nanoseconds using the tsc. This function 1768 * returns immediately if the TSC is not supported. At least one cpu_pause() 1769 * will be issued. 1770 */ 1771 void 1772 tsc_delay(int ns) 1773 { 1774 int64_t clk; 1775 1776 clk = tsc_get_target(ns); 1777 cpu_pause(); 1778 cpu_pause(); 1779 while (tsc_test_target(clk) == 0) { 1780 cpu_pause(); 1781 cpu_pause(); 1782 cpu_pause(); 1783 cpu_pause(); 1784 } 1785 } 1786