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