1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2010-2013 Alexander Motin <mav@FreeBSD.org> 5 * All rights reserved. 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 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer, 12 * without modification, immediately at the beginning of the file. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 /* 31 * Common routines to manage event timers hardware. 32 */ 33 34 #include "opt_device_polling.h" 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/bus.h> 39 #include <sys/limits.h> 40 #include <sys/lock.h> 41 #include <sys/kdb.h> 42 #include <sys/ktr.h> 43 #include <sys/mutex.h> 44 #include <sys/proc.h> 45 #include <sys/kernel.h> 46 #include <sys/sched.h> 47 #include <sys/smp.h> 48 #include <sys/sysctl.h> 49 #include <sys/timeet.h> 50 #include <sys/timetc.h> 51 52 #include <machine/atomic.h> 53 #include <machine/clock.h> 54 #include <machine/cpu.h> 55 #include <machine/smp.h> 56 57 int cpu_disable_c2_sleep = 0; /* Timer dies in C2. */ 58 int cpu_disable_c3_sleep = 0; /* Timer dies in C3. */ 59 60 static void setuptimer(void); 61 static void loadtimer(sbintime_t now, int first); 62 static int doconfigtimer(void); 63 static void configtimer(int start); 64 static int round_freq(struct eventtimer *et, int freq); 65 66 struct pcpu_state; 67 static sbintime_t getnextcpuevent(struct pcpu_state *state, int idle); 68 static sbintime_t getnextevent(struct pcpu_state *state); 69 static int handleevents(sbintime_t now, int fake); 70 71 static struct mtx et_hw_mtx; 72 73 #define ET_HW_LOCK(state) \ 74 { \ 75 if (timer->et_flags & ET_FLAGS_PERCPU) \ 76 mtx_lock_spin(&(state)->et_hw_mtx); \ 77 else \ 78 mtx_lock_spin(&et_hw_mtx); \ 79 } 80 81 #define ET_HW_UNLOCK(state) \ 82 { \ 83 if (timer->et_flags & ET_FLAGS_PERCPU) \ 84 mtx_unlock_spin(&(state)->et_hw_mtx); \ 85 else \ 86 mtx_unlock_spin(&et_hw_mtx); \ 87 } 88 89 static struct eventtimer *timer = NULL; 90 static sbintime_t timerperiod; /* Timer period for periodic mode. */ 91 static sbintime_t statperiod; /* statclock() events period. */ 92 static sbintime_t profperiod; /* profclock() events period. */ 93 static sbintime_t nexttick; /* Next global timer tick time. */ 94 static u_int busy = 1; /* Reconfiguration is in progress. */ 95 static int profiling; /* Profiling events enabled. */ 96 97 static char timername[32]; /* Wanted timer. */ 98 TUNABLE_STR("kern.eventtimer.timer", timername, sizeof(timername)); 99 100 static int singlemul; /* Multiplier for periodic mode. */ 101 SYSCTL_INT(_kern_eventtimer, OID_AUTO, singlemul, CTLFLAG_RWTUN, &singlemul, 102 0, "Multiplier for periodic mode"); 103 104 static u_int idletick; /* Run periodic events when idle. */ 105 SYSCTL_UINT(_kern_eventtimer, OID_AUTO, idletick, CTLFLAG_RWTUN, &idletick, 106 0, "Run periodic events when idle"); 107 108 static int periodic; /* Periodic or one-shot mode. */ 109 static int want_periodic; /* What mode to prefer. */ 110 TUNABLE_INT("kern.eventtimer.periodic", &want_periodic); 111 112 struct pcpu_state { 113 struct mtx et_hw_mtx; /* Per-CPU timer mutex. */ 114 u_int action; /* Reconfiguration requests. */ 115 u_int handle; /* Immediate handle resuests. */ 116 sbintime_t now; /* Last tick time. */ 117 sbintime_t nextevent; /* Next scheduled event on this CPU. */ 118 sbintime_t nexttick; /* Next timer tick time. */ 119 sbintime_t nexthard; /* Next hardclock() event. */ 120 sbintime_t nextstat; /* Next statclock() event. */ 121 sbintime_t nextprof; /* Next profclock() event. */ 122 sbintime_t nextcall; /* Next callout event. */ 123 sbintime_t nextcallopt; /* Next optional callout event. */ 124 int ipi; /* This CPU needs IPI. */ 125 int idle; /* This CPU is in idle mode. */ 126 }; 127 128 DPCPU_DEFINE_STATIC(struct pcpu_state, timerstate); 129 DPCPU_DEFINE(sbintime_t, hardclocktime); 130 131 /* 132 * Timer broadcast IPI handler. 133 */ 134 int 135 hardclockintr(void) 136 { 137 sbintime_t now; 138 struct pcpu_state *state; 139 int done; 140 141 if (doconfigtimer() || busy) 142 return (FILTER_HANDLED); 143 state = DPCPU_PTR(timerstate); 144 now = state->now; 145 CTR2(KTR_SPARE2, "ipi: now %d.%08x", 146 (int)(now >> 32), (u_int)(now & 0xffffffff)); 147 done = handleevents(now, 0); 148 return (done ? FILTER_HANDLED : FILTER_STRAY); 149 } 150 151 /* 152 * Handle all events for specified time on this CPU 153 */ 154 static int 155 handleevents(sbintime_t now, int fake) 156 { 157 sbintime_t t, *hct; 158 struct trapframe *frame; 159 struct pcpu_state *state; 160 int usermode; 161 int done, runs; 162 163 CTR2(KTR_SPARE2, "handle: now %d.%08x", 164 (int)(now >> 32), (u_int)(now & 0xffffffff)); 165 done = 0; 166 if (fake) { 167 frame = NULL; 168 usermode = 0; 169 } else { 170 frame = curthread->td_intr_frame; 171 usermode = TRAPF_USERMODE(frame); 172 } 173 174 state = DPCPU_PTR(timerstate); 175 176 runs = 0; 177 while (now >= state->nexthard) { 178 state->nexthard += tick_sbt; 179 runs++; 180 } 181 if (runs) { 182 hct = DPCPU_PTR(hardclocktime); 183 *hct = state->nexthard - tick_sbt; 184 if (fake < 2) { 185 hardclock(runs, usermode); 186 done = 1; 187 } 188 } 189 runs = 0; 190 while (now >= state->nextstat) { 191 state->nextstat += statperiod; 192 runs++; 193 } 194 if (runs && fake < 2) { 195 statclock(runs, usermode); 196 done = 1; 197 } 198 if (profiling) { 199 runs = 0; 200 while (now >= state->nextprof) { 201 state->nextprof += profperiod; 202 runs++; 203 } 204 if (runs && !fake) { 205 profclock(runs, usermode, TRAPF_PC(frame)); 206 done = 1; 207 } 208 } else 209 state->nextprof = state->nextstat; 210 if (now >= state->nextcallopt || now >= state->nextcall) { 211 state->nextcall = state->nextcallopt = SBT_MAX; 212 callout_process(now); 213 } 214 215 ET_HW_LOCK(state); 216 t = getnextcpuevent(state, 0); 217 if (!busy) { 218 state->idle = 0; 219 state->nextevent = t; 220 loadtimer(now, (fake == 2) && 221 (timer->et_flags & ET_FLAGS_PERCPU)); 222 } 223 ET_HW_UNLOCK(state); 224 return (done); 225 } 226 227 /* 228 * Schedule binuptime of the next event on current CPU. 229 */ 230 static sbintime_t 231 getnextcpuevent(struct pcpu_state *state, int idle) 232 { 233 sbintime_t event; 234 u_int hardfreq; 235 236 /* Handle hardclock() events, skipping some if CPU is idle. */ 237 event = state->nexthard; 238 if (idle) { 239 if (tc_min_ticktock_freq > 1 240 #ifdef SMP 241 && curcpu == CPU_FIRST() 242 #endif 243 ) 244 hardfreq = hz / tc_min_ticktock_freq; 245 else 246 hardfreq = hz; 247 if (hardfreq > 1) 248 event += tick_sbt * (hardfreq - 1); 249 } 250 /* Handle callout events. */ 251 if (event > state->nextcall) 252 event = state->nextcall; 253 if (!idle) { /* If CPU is active - handle other types of events. */ 254 if (event > state->nextstat) 255 event = state->nextstat; 256 if (profiling && event > state->nextprof) 257 event = state->nextprof; 258 } 259 return (event); 260 } 261 262 /* 263 * Schedule binuptime of the next event on all CPUs. 264 */ 265 static sbintime_t 266 getnextevent(struct pcpu_state *state) 267 { 268 sbintime_t event; 269 #ifdef SMP 270 int cpu; 271 #endif 272 #ifdef KTR 273 int c; 274 275 c = -1; 276 #endif 277 event = state->nextevent; 278 #ifdef SMP 279 if ((timer->et_flags & ET_FLAGS_PERCPU) == 0) { 280 CPU_FOREACH(cpu) { 281 state = DPCPU_ID_PTR(cpu, timerstate); 282 if (event > state->nextevent) { 283 event = state->nextevent; 284 #ifdef KTR 285 c = cpu; 286 #endif 287 } 288 } 289 } 290 #endif 291 CTR3(KTR_SPARE2, "next: next %d.%08x by %d", 292 (int)(event >> 32), (u_int)(event & 0xffffffff), c); 293 return (event); 294 } 295 296 /* Hardware timer callback function. */ 297 static void 298 timercb(struct eventtimer *et, void *arg) 299 { 300 sbintime_t now; 301 sbintime_t *next; 302 struct pcpu_state *state; 303 #ifdef SMP 304 int cpu, bcast; 305 #endif 306 307 /* Do not touch anything if somebody reconfiguring timers. */ 308 if (busy) 309 return; 310 /* Update present and next tick times. */ 311 state = DPCPU_PTR(timerstate); 312 if (et->et_flags & ET_FLAGS_PERCPU) { 313 next = &state->nexttick; 314 } else 315 next = &nexttick; 316 now = sbinuptime(); 317 if (periodic) 318 *next = now + timerperiod; 319 else 320 *next = -1; /* Next tick is not scheduled yet. */ 321 state->now = now; 322 CTR2(KTR_SPARE2, "intr: now %d.%08x", 323 (int)(now >> 32), (u_int)(now & 0xffffffff)); 324 325 #ifdef SMP 326 #ifdef EARLY_AP_STARTUP 327 MPASS(mp_ncpus == 1 || smp_started); 328 #endif 329 /* Prepare broadcasting to other CPUs for non-per-CPU timers. */ 330 bcast = 0; 331 #ifdef EARLY_AP_STARTUP 332 if ((et->et_flags & ET_FLAGS_PERCPU) == 0) { 333 #else 334 if ((et->et_flags & ET_FLAGS_PERCPU) == 0 && smp_started) { 335 #endif 336 CPU_FOREACH(cpu) { 337 state = DPCPU_ID_PTR(cpu, timerstate); 338 ET_HW_LOCK(state); 339 state->now = now; 340 if (now >= state->nextevent) { 341 state->nextevent += SBT_1S; 342 if (curcpu != cpu) { 343 state->ipi = 1; 344 bcast = 1; 345 } 346 } 347 ET_HW_UNLOCK(state); 348 } 349 } 350 #endif 351 352 /* Handle events for this time on this CPU. */ 353 handleevents(now, 0); 354 355 #ifdef SMP 356 /* Broadcast interrupt to other CPUs for non-per-CPU timers. */ 357 if (bcast) { 358 CPU_FOREACH(cpu) { 359 if (curcpu == cpu) 360 continue; 361 state = DPCPU_ID_PTR(cpu, timerstate); 362 if (state->ipi) { 363 state->ipi = 0; 364 ipi_cpu(cpu, IPI_HARDCLOCK); 365 } 366 } 367 } 368 #endif 369 } 370 371 /* 372 * Load new value into hardware timer. 373 */ 374 static void 375 loadtimer(sbintime_t now, int start) 376 { 377 struct pcpu_state *state; 378 sbintime_t new; 379 sbintime_t *next; 380 uint64_t tmp; 381 int eq; 382 383 state = DPCPU_PTR(timerstate); 384 if (timer->et_flags & ET_FLAGS_PERCPU) 385 next = &state->nexttick; 386 else 387 next = &nexttick; 388 if (periodic) { 389 if (start) { 390 /* 391 * Try to start all periodic timers aligned 392 * to period to make events synchronous. 393 */ 394 tmp = now % timerperiod; 395 new = timerperiod - tmp; 396 if (new < tmp) /* Left less then passed. */ 397 new += timerperiod; 398 CTR4(KTR_SPARE2, "load p: now %d.%08x first in %d.%08x", 399 (int)(now >> 32), (u_int)(now & 0xffffffff), 400 (int)(new >> 32), (u_int)(new & 0xffffffff)); 401 *next = new + now; 402 et_start(timer, new, timerperiod); 403 } 404 } else { 405 new = getnextevent(state); 406 eq = (new == *next); 407 CTR3(KTR_SPARE2, "load: next %d.%08x eq %d", 408 (int)(new >> 32), (u_int)(new & 0xffffffff), eq); 409 if (!eq) { 410 *next = new; 411 et_start(timer, new - now, 0); 412 } 413 } 414 } 415 416 /* 417 * Prepare event timer parameters after configuration changes. 418 */ 419 static void 420 setuptimer(void) 421 { 422 int freq; 423 424 if (periodic && (timer->et_flags & ET_FLAGS_PERIODIC) == 0) 425 periodic = 0; 426 else if (!periodic && (timer->et_flags & ET_FLAGS_ONESHOT) == 0) 427 periodic = 1; 428 singlemul = MIN(MAX(singlemul, 1), 20); 429 freq = hz * singlemul; 430 while (freq < (profiling ? profhz : stathz)) 431 freq += hz; 432 freq = round_freq(timer, freq); 433 timerperiod = SBT_1S / freq; 434 } 435 436 /* 437 * Reconfigure specified per-CPU timer on other CPU. Called from IPI handler. 438 */ 439 static int 440 doconfigtimer(void) 441 { 442 sbintime_t now; 443 struct pcpu_state *state; 444 445 state = DPCPU_PTR(timerstate); 446 switch (atomic_load_acq_int(&state->action)) { 447 case 1: 448 now = sbinuptime(); 449 ET_HW_LOCK(state); 450 loadtimer(now, 1); 451 ET_HW_UNLOCK(state); 452 state->handle = 0; 453 atomic_store_rel_int(&state->action, 0); 454 return (1); 455 case 2: 456 ET_HW_LOCK(state); 457 et_stop(timer); 458 ET_HW_UNLOCK(state); 459 state->handle = 0; 460 atomic_store_rel_int(&state->action, 0); 461 return (1); 462 } 463 if (atomic_readandclear_int(&state->handle) && !busy) { 464 now = sbinuptime(); 465 handleevents(now, 0); 466 return (1); 467 } 468 return (0); 469 } 470 471 /* 472 * Reconfigure specified timer. 473 * For per-CPU timers use IPI to make other CPUs to reconfigure. 474 */ 475 static void 476 configtimer(int start) 477 { 478 sbintime_t now, next; 479 struct pcpu_state *state; 480 int cpu; 481 482 if (start) { 483 setuptimer(); 484 now = sbinuptime(); 485 } else 486 now = 0; 487 critical_enter(); 488 ET_HW_LOCK(DPCPU_PTR(timerstate)); 489 if (start) { 490 /* Initialize time machine parameters. */ 491 next = now + timerperiod; 492 if (periodic) 493 nexttick = next; 494 else 495 nexttick = -1; 496 #ifdef EARLY_AP_STARTUP 497 MPASS(mp_ncpus == 1 || smp_started); 498 #endif 499 CPU_FOREACH(cpu) { 500 state = DPCPU_ID_PTR(cpu, timerstate); 501 state->now = now; 502 #ifndef EARLY_AP_STARTUP 503 if (!smp_started && cpu != CPU_FIRST()) 504 state->nextevent = SBT_MAX; 505 else 506 #endif 507 state->nextevent = next; 508 if (periodic) 509 state->nexttick = next; 510 else 511 state->nexttick = -1; 512 state->nexthard = next; 513 state->nextstat = next; 514 state->nextprof = next; 515 state->nextcall = next; 516 state->nextcallopt = next; 517 hardclock_sync(cpu); 518 } 519 busy = 0; 520 /* Start global timer or per-CPU timer of this CPU. */ 521 loadtimer(now, 1); 522 } else { 523 busy = 1; 524 /* Stop global timer or per-CPU timer of this CPU. */ 525 et_stop(timer); 526 } 527 ET_HW_UNLOCK(DPCPU_PTR(timerstate)); 528 #ifdef SMP 529 #ifdef EARLY_AP_STARTUP 530 /* If timer is global we are done. */ 531 if ((timer->et_flags & ET_FLAGS_PERCPU) == 0) { 532 #else 533 /* If timer is global or there is no other CPUs yet - we are done. */ 534 if ((timer->et_flags & ET_FLAGS_PERCPU) == 0 || !smp_started) { 535 #endif 536 critical_exit(); 537 return; 538 } 539 /* Set reconfigure flags for other CPUs. */ 540 CPU_FOREACH(cpu) { 541 state = DPCPU_ID_PTR(cpu, timerstate); 542 atomic_store_rel_int(&state->action, 543 (cpu == curcpu) ? 0 : ( start ? 1 : 2)); 544 } 545 /* Broadcast reconfigure IPI. */ 546 ipi_all_but_self(IPI_HARDCLOCK); 547 /* Wait for reconfiguration completed. */ 548 restart: 549 cpu_spinwait(); 550 CPU_FOREACH(cpu) { 551 if (cpu == curcpu) 552 continue; 553 state = DPCPU_ID_PTR(cpu, timerstate); 554 if (atomic_load_acq_int(&state->action)) 555 goto restart; 556 } 557 #endif 558 critical_exit(); 559 } 560 561 /* 562 * Calculate nearest frequency supported by hardware timer. 563 */ 564 static int 565 round_freq(struct eventtimer *et, int freq) 566 { 567 uint64_t div; 568 569 if (et->et_frequency != 0) { 570 div = lmax((et->et_frequency + freq / 2) / freq, 1); 571 if (et->et_flags & ET_FLAGS_POW2DIV) 572 div = 1 << (flsl(div + div / 2) - 1); 573 freq = (et->et_frequency + div / 2) / div; 574 } 575 if (et->et_min_period > SBT_1S) 576 panic("Event timer \"%s\" doesn't support sub-second periods!", 577 et->et_name); 578 else if (et->et_min_period != 0) 579 freq = min(freq, SBT2FREQ(et->et_min_period)); 580 if (et->et_max_period < SBT_1S && et->et_max_period != 0) 581 freq = max(freq, SBT2FREQ(et->et_max_period)); 582 return (freq); 583 } 584 585 /* 586 * Configure and start event timers (BSP part). 587 */ 588 void 589 cpu_initclocks_bsp(void) 590 { 591 struct pcpu_state *state; 592 int base, div, cpu; 593 594 mtx_init(&et_hw_mtx, "et_hw_mtx", NULL, MTX_SPIN); 595 CPU_FOREACH(cpu) { 596 state = DPCPU_ID_PTR(cpu, timerstate); 597 mtx_init(&state->et_hw_mtx, "et_hw_mtx", NULL, MTX_SPIN); 598 state->nextcall = SBT_MAX; 599 state->nextcallopt = SBT_MAX; 600 } 601 periodic = want_periodic; 602 /* Grab requested timer or the best of present. */ 603 if (timername[0]) 604 timer = et_find(timername, 0, 0); 605 if (timer == NULL && periodic) { 606 timer = et_find(NULL, 607 ET_FLAGS_PERIODIC, ET_FLAGS_PERIODIC); 608 } 609 if (timer == NULL) { 610 timer = et_find(NULL, 611 ET_FLAGS_ONESHOT, ET_FLAGS_ONESHOT); 612 } 613 if (timer == NULL && !periodic) { 614 timer = et_find(NULL, 615 ET_FLAGS_PERIODIC, ET_FLAGS_PERIODIC); 616 } 617 if (timer == NULL) 618 panic("No usable event timer found!"); 619 et_init(timer, timercb, NULL, NULL); 620 621 /* Adapt to timer capabilities. */ 622 if (periodic && (timer->et_flags & ET_FLAGS_PERIODIC) == 0) 623 periodic = 0; 624 else if (!periodic && (timer->et_flags & ET_FLAGS_ONESHOT) == 0) 625 periodic = 1; 626 if (timer->et_flags & ET_FLAGS_C3STOP) 627 cpu_disable_c3_sleep++; 628 629 /* 630 * We honor the requested 'hz' value. 631 * We want to run stathz in the neighborhood of 128hz. 632 * We would like profhz to run as often as possible. 633 */ 634 if (singlemul <= 0 || singlemul > 20) { 635 if (hz >= 1500 || (hz % 128) == 0) 636 singlemul = 1; 637 else if (hz >= 750) 638 singlemul = 2; 639 else 640 singlemul = 4; 641 } 642 if (periodic) { 643 base = round_freq(timer, hz * singlemul); 644 singlemul = max((base + hz / 2) / hz, 1); 645 hz = (base + singlemul / 2) / singlemul; 646 if (base <= 128) 647 stathz = base; 648 else { 649 div = base / 128; 650 if (div >= singlemul && (div % singlemul) == 0) 651 div++; 652 stathz = base / div; 653 } 654 profhz = stathz; 655 while ((profhz + stathz) <= 128 * 64) 656 profhz += stathz; 657 profhz = round_freq(timer, profhz); 658 } else { 659 hz = round_freq(timer, hz); 660 stathz = round_freq(timer, 127); 661 profhz = round_freq(timer, stathz * 64); 662 } 663 tick = 1000000 / hz; 664 tick_sbt = SBT_1S / hz; 665 tick_bt = sbttobt(tick_sbt); 666 statperiod = SBT_1S / stathz; 667 profperiod = SBT_1S / profhz; 668 ET_LOCK(); 669 configtimer(1); 670 ET_UNLOCK(); 671 } 672 673 /* 674 * Start per-CPU event timers on APs. 675 */ 676 void 677 cpu_initclocks_ap(void) 678 { 679 struct pcpu_state *state; 680 struct thread *td; 681 682 state = DPCPU_PTR(timerstate); 683 ET_HW_LOCK(state); 684 state->now = sbinuptime(); 685 hardclock_sync(curcpu); 686 spinlock_enter(); 687 ET_HW_UNLOCK(state); 688 td = curthread; 689 td->td_intr_nesting_level++; 690 handleevents(state->now, 2); 691 td->td_intr_nesting_level--; 692 spinlock_exit(); 693 } 694 695 void 696 suspendclock(void) 697 { 698 ET_LOCK(); 699 configtimer(0); 700 ET_UNLOCK(); 701 } 702 703 void 704 resumeclock(void) 705 { 706 ET_LOCK(); 707 configtimer(1); 708 ET_UNLOCK(); 709 } 710 711 /* 712 * Switch to profiling clock rates. 713 */ 714 void 715 cpu_startprofclock(void) 716 { 717 718 ET_LOCK(); 719 if (profiling == 0) { 720 if (periodic) { 721 configtimer(0); 722 profiling = 1; 723 configtimer(1); 724 } else 725 profiling = 1; 726 } else 727 profiling++; 728 ET_UNLOCK(); 729 } 730 731 /* 732 * Switch to regular clock rates. 733 */ 734 void 735 cpu_stopprofclock(void) 736 { 737 738 ET_LOCK(); 739 if (profiling == 1) { 740 if (periodic) { 741 configtimer(0); 742 profiling = 0; 743 configtimer(1); 744 } else 745 profiling = 0; 746 } else 747 profiling--; 748 ET_UNLOCK(); 749 } 750 751 /* 752 * Switch to idle mode (all ticks handled). 753 */ 754 sbintime_t 755 cpu_idleclock(void) 756 { 757 sbintime_t now, t; 758 struct pcpu_state *state; 759 760 if (idletick || busy || 761 (periodic && (timer->et_flags & ET_FLAGS_PERCPU)) 762 #ifdef DEVICE_POLLING 763 || curcpu == CPU_FIRST() 764 #endif 765 ) 766 return (-1); 767 state = DPCPU_PTR(timerstate); 768 ET_HW_LOCK(state); 769 if (periodic) 770 now = state->now; 771 else 772 now = sbinuptime(); 773 CTR2(KTR_SPARE2, "idle: now %d.%08x", 774 (int)(now >> 32), (u_int)(now & 0xffffffff)); 775 t = getnextcpuevent(state, 1); 776 state->idle = 1; 777 state->nextevent = t; 778 if (!periodic) 779 loadtimer(now, 0); 780 ET_HW_UNLOCK(state); 781 return (MAX(t - now, 0)); 782 } 783 784 /* 785 * Switch to active mode (skip empty ticks). 786 */ 787 void 788 cpu_activeclock(void) 789 { 790 sbintime_t now; 791 struct pcpu_state *state; 792 struct thread *td; 793 794 state = DPCPU_PTR(timerstate); 795 if (atomic_load_int(&state->idle) == 0 || busy) 796 return; 797 spinlock_enter(); 798 if (periodic) 799 now = state->now; 800 else 801 now = sbinuptime(); 802 CTR2(KTR_SPARE2, "active: now %d.%08x", 803 (int)(now >> 32), (u_int)(now & 0xffffffff)); 804 td = curthread; 805 td->td_intr_nesting_level++; 806 handleevents(now, 1); 807 td->td_intr_nesting_level--; 808 spinlock_exit(); 809 } 810 811 /* 812 * Change the frequency of the given timer. This changes et->et_frequency and 813 * if et is the active timer it reconfigures the timer on all CPUs. This is 814 * intended to be a private interface for the use of et_change_frequency() only. 815 */ 816 void 817 cpu_et_frequency(struct eventtimer *et, uint64_t newfreq) 818 { 819 820 ET_LOCK(); 821 if (et == timer) { 822 configtimer(0); 823 et->et_frequency = newfreq; 824 configtimer(1); 825 } else 826 et->et_frequency = newfreq; 827 ET_UNLOCK(); 828 } 829 830 void 831 cpu_new_callout(int cpu, sbintime_t bt, sbintime_t bt_opt) 832 { 833 struct pcpu_state *state; 834 835 /* Do not touch anything if somebody reconfiguring timers. */ 836 if (busy) 837 return; 838 839 CTR5(KTR_SPARE2, "new co: on %d at %d.%08x - %d.%08x", 840 cpu, (int)(bt_opt >> 32), (u_int)(bt_opt & 0xffffffff), 841 (int)(bt >> 32), (u_int)(bt & 0xffffffff)); 842 843 KASSERT(!CPU_ABSENT(cpu), ("Absent CPU %d", cpu)); 844 state = DPCPU_ID_PTR(cpu, timerstate); 845 ET_HW_LOCK(state); 846 847 /* 848 * If there is callout time already set earlier -- do nothing. 849 * This check may appear redundant because we check already in 850 * callout_process() but this double check guarantees we're safe 851 * with respect to race conditions between interrupts execution 852 * and scheduling. 853 */ 854 state->nextcallopt = bt_opt; 855 if (bt >= state->nextcall) 856 goto done; 857 state->nextcall = bt; 858 /* If there is some other event set earlier -- do nothing. */ 859 if (bt >= state->nextevent) 860 goto done; 861 state->nextevent = bt; 862 /* If timer is periodic -- there is nothing to reprogram. */ 863 if (periodic) 864 goto done; 865 /* If timer is global or of the current CPU -- reprogram it. */ 866 if ((timer->et_flags & ET_FLAGS_PERCPU) == 0 || cpu == curcpu) { 867 loadtimer(sbinuptime(), 0); 868 done: 869 ET_HW_UNLOCK(state); 870 return; 871 } 872 /* Otherwise make other CPU to reprogram it. */ 873 state->handle = 1; 874 ET_HW_UNLOCK(state); 875 #ifdef SMP 876 ipi_cpu(cpu, IPI_HARDCLOCK); 877 #endif 878 } 879 880 /* 881 * Report or change the active event timers hardware. 882 */ 883 static int 884 sysctl_kern_eventtimer_timer(SYSCTL_HANDLER_ARGS) 885 { 886 char buf[32]; 887 struct eventtimer *et; 888 int error; 889 890 ET_LOCK(); 891 et = timer; 892 snprintf(buf, sizeof(buf), "%s", et->et_name); 893 ET_UNLOCK(); 894 error = sysctl_handle_string(oidp, buf, sizeof(buf), req); 895 ET_LOCK(); 896 et = timer; 897 if (error != 0 || req->newptr == NULL || 898 strcasecmp(buf, et->et_name) == 0) { 899 ET_UNLOCK(); 900 return (error); 901 } 902 et = et_find(buf, 0, 0); 903 if (et == NULL) { 904 ET_UNLOCK(); 905 return (ENOENT); 906 } 907 configtimer(0); 908 et_free(timer); 909 if (et->et_flags & ET_FLAGS_C3STOP) 910 cpu_disable_c3_sleep++; 911 if (timer->et_flags & ET_FLAGS_C3STOP) 912 cpu_disable_c3_sleep--; 913 periodic = want_periodic; 914 timer = et; 915 et_init(timer, timercb, NULL, NULL); 916 configtimer(1); 917 ET_UNLOCK(); 918 return (error); 919 } 920 SYSCTL_PROC(_kern_eventtimer, OID_AUTO, timer, 921 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_MPSAFE, 922 0, 0, sysctl_kern_eventtimer_timer, "A", "Chosen event timer"); 923 924 /* 925 * Report or change the active event timer periodicity. 926 */ 927 static int 928 sysctl_kern_eventtimer_periodic(SYSCTL_HANDLER_ARGS) 929 { 930 int error, val; 931 932 val = periodic; 933 error = sysctl_handle_int(oidp, &val, 0, req); 934 if (error != 0 || req->newptr == NULL) 935 return (error); 936 ET_LOCK(); 937 configtimer(0); 938 periodic = want_periodic = val; 939 configtimer(1); 940 ET_UNLOCK(); 941 return (error); 942 } 943 SYSCTL_PROC(_kern_eventtimer, OID_AUTO, periodic, 944 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 945 0, 0, sysctl_kern_eventtimer_periodic, "I", "Enable event timer periodic mode"); 946 947 #include "opt_ddb.h" 948 949 #ifdef DDB 950 #include <ddb/ddb.h> 951 952 DB_SHOW_COMMAND(clocksource, db_show_clocksource) 953 { 954 struct pcpu_state *st; 955 int c; 956 957 CPU_FOREACH(c) { 958 st = DPCPU_ID_PTR(c, timerstate); 959 db_printf( 960 "CPU %2d: action %d handle %d ipi %d idle %d\n" 961 " now %#jx nevent %#jx (%jd)\n" 962 " ntick %#jx (%jd) nhard %#jx (%jd)\n" 963 " nstat %#jx (%jd) nprof %#jx (%jd)\n" 964 " ncall %#jx (%jd) ncallopt %#jx (%jd)\n", 965 c, st->action, st->handle, st->ipi, st->idle, 966 (uintmax_t)st->now, 967 (uintmax_t)st->nextevent, 968 (uintmax_t)(st->nextevent - st->now) / tick_sbt, 969 (uintmax_t)st->nexttick, 970 (uintmax_t)(st->nexttick - st->now) / tick_sbt, 971 (uintmax_t)st->nexthard, 972 (uintmax_t)(st->nexthard - st->now) / tick_sbt, 973 (uintmax_t)st->nextstat, 974 (uintmax_t)(st->nextstat - st->now) / tick_sbt, 975 (uintmax_t)st->nextprof, 976 (uintmax_t)(st->nextprof - st->now) / tick_sbt, 977 (uintmax_t)st->nextcall, 978 (uintmax_t)(st->nextcall - st->now) / tick_sbt, 979 (uintmax_t)st->nextcallopt, 980 (uintmax_t)(st->nextcallopt - st->now) / tick_sbt); 981 } 982 } 983 984 #endif 985