1 /*- 2 * Copyright (c) 2010-2013 Alexander Motin <mav@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer, 10 * without modification, immediately at the beginning of the file. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 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 #ifdef KDTRACE_HOOKS 58 #include <sys/dtrace_bsd.h> 59 cyclic_clock_func_t cyclic_clock_func = NULL; 60 #endif 61 62 int cpu_can_deep_sleep = 0; /* C3 state is available. */ 63 int cpu_disable_deep_sleep = 0; /* Timer dies in C3. */ 64 65 static void setuptimer(void); 66 static void loadtimer(sbintime_t now, int first); 67 static int doconfigtimer(void); 68 static void configtimer(int start); 69 static int round_freq(struct eventtimer *et, int freq); 70 71 static sbintime_t getnextcpuevent(int idle); 72 static sbintime_t getnextevent(void); 73 static int handleevents(sbintime_t now, int fake); 74 75 static struct mtx et_hw_mtx; 76 77 #define ET_HW_LOCK(state) \ 78 { \ 79 if (timer->et_flags & ET_FLAGS_PERCPU) \ 80 mtx_lock_spin(&(state)->et_hw_mtx); \ 81 else \ 82 mtx_lock_spin(&et_hw_mtx); \ 83 } 84 85 #define ET_HW_UNLOCK(state) \ 86 { \ 87 if (timer->et_flags & ET_FLAGS_PERCPU) \ 88 mtx_unlock_spin(&(state)->et_hw_mtx); \ 89 else \ 90 mtx_unlock_spin(&et_hw_mtx); \ 91 } 92 93 static struct eventtimer *timer = NULL; 94 static sbintime_t timerperiod; /* Timer period for periodic mode. */ 95 static sbintime_t statperiod; /* statclock() events period. */ 96 static sbintime_t profperiod; /* profclock() events period. */ 97 static sbintime_t nexttick; /* Next global timer tick time. */ 98 static u_int busy = 1; /* Reconfiguration is in progress. */ 99 static int profiling; /* Profiling events enabled. */ 100 101 static char timername[32]; /* Wanted timer. */ 102 TUNABLE_STR("kern.eventtimer.timer", timername, sizeof(timername)); 103 104 static int singlemul; /* Multiplier for periodic mode. */ 105 SYSCTL_INT(_kern_eventtimer, OID_AUTO, singlemul, CTLFLAG_RWTUN, &singlemul, 106 0, "Multiplier for periodic mode"); 107 108 static u_int idletick; /* Run periodic events when idle. */ 109 SYSCTL_UINT(_kern_eventtimer, OID_AUTO, idletick, CTLFLAG_RWTUN, &idletick, 110 0, "Run periodic events when idle"); 111 112 static int periodic; /* Periodic or one-shot mode. */ 113 static int want_periodic; /* What mode to prefer. */ 114 TUNABLE_INT("kern.eventtimer.periodic", &want_periodic); 115 116 struct pcpu_state { 117 struct mtx et_hw_mtx; /* Per-CPU timer mutex. */ 118 u_int action; /* Reconfiguration requests. */ 119 u_int handle; /* Immediate handle resuests. */ 120 sbintime_t now; /* Last tick time. */ 121 sbintime_t nextevent; /* Next scheduled event on this CPU. */ 122 sbintime_t nexttick; /* Next timer tick time. */ 123 sbintime_t nexthard; /* Next hardlock() event. */ 124 sbintime_t nextstat; /* Next statclock() event. */ 125 sbintime_t nextprof; /* Next profclock() event. */ 126 sbintime_t nextcall; /* Next callout event. */ 127 sbintime_t nextcallopt; /* Next optional callout event. */ 128 #ifdef KDTRACE_HOOKS 129 sbintime_t nextcyc; /* Next OpenSolaris cyclics event. */ 130 #endif 131 int ipi; /* This CPU needs IPI. */ 132 int idle; /* This CPU is in idle mode. */ 133 }; 134 135 static DPCPU_DEFINE(struct pcpu_state, timerstate); 136 DPCPU_DEFINE(sbintime_t, hardclocktime); 137 138 /* 139 * Timer broadcast IPI handler. 140 */ 141 int 142 hardclockintr(void) 143 { 144 sbintime_t now; 145 struct pcpu_state *state; 146 int done; 147 148 if (doconfigtimer() || busy) 149 return (FILTER_HANDLED); 150 state = DPCPU_PTR(timerstate); 151 now = state->now; 152 CTR3(KTR_SPARE2, "ipi at %d: now %d.%08x", 153 curcpu, (int)(now >> 32), (u_int)(now & 0xffffffff)); 154 done = handleevents(now, 0); 155 return (done ? FILTER_HANDLED : FILTER_STRAY); 156 } 157 158 /* 159 * Handle all events for specified time on this CPU 160 */ 161 static int 162 handleevents(sbintime_t now, int fake) 163 { 164 sbintime_t t, *hct; 165 struct trapframe *frame; 166 struct pcpu_state *state; 167 int usermode; 168 int done, runs; 169 170 CTR3(KTR_SPARE2, "handle at %d: now %d.%08x", 171 curcpu, (int)(now >> 32), (u_int)(now & 0xffffffff)); 172 done = 0; 173 if (fake) { 174 frame = NULL; 175 usermode = 0; 176 } else { 177 frame = curthread->td_intr_frame; 178 usermode = TRAPF_USERMODE(frame); 179 } 180 181 state = DPCPU_PTR(timerstate); 182 183 runs = 0; 184 while (now >= state->nexthard) { 185 state->nexthard += tick_sbt; 186 runs++; 187 } 188 if (runs) { 189 hct = DPCPU_PTR(hardclocktime); 190 *hct = state->nexthard - tick_sbt; 191 if (fake < 2) { 192 hardclock_cnt(runs, usermode); 193 done = 1; 194 } 195 } 196 runs = 0; 197 while (now >= state->nextstat) { 198 state->nextstat += statperiod; 199 runs++; 200 } 201 if (runs && fake < 2) { 202 statclock_cnt(runs, usermode); 203 done = 1; 204 } 205 if (profiling) { 206 runs = 0; 207 while (now >= state->nextprof) { 208 state->nextprof += profperiod; 209 runs++; 210 } 211 if (runs && !fake) { 212 profclock_cnt(runs, usermode, TRAPF_PC(frame)); 213 done = 1; 214 } 215 } else 216 state->nextprof = state->nextstat; 217 if (now >= state->nextcallopt) { 218 state->nextcall = state->nextcallopt = SBT_MAX; 219 callout_process(now); 220 } 221 222 #ifdef KDTRACE_HOOKS 223 if (fake == 0 && now >= state->nextcyc && cyclic_clock_func != NULL) { 224 state->nextcyc = SBT_MAX; 225 (*cyclic_clock_func)(frame); 226 } 227 #endif 228 229 t = getnextcpuevent(0); 230 ET_HW_LOCK(state); 231 if (!busy) { 232 state->idle = 0; 233 state->nextevent = t; 234 loadtimer(now, (fake == 2) && 235 (timer->et_flags & ET_FLAGS_PERCPU)); 236 } 237 ET_HW_UNLOCK(state); 238 return (done); 239 } 240 241 /* 242 * Schedule binuptime of the next event on current CPU. 243 */ 244 static sbintime_t 245 getnextcpuevent(int idle) 246 { 247 sbintime_t event; 248 struct pcpu_state *state; 249 u_int hardfreq; 250 251 state = DPCPU_PTR(timerstate); 252 /* Handle hardclock() events, skipping some if CPU is idle. */ 253 event = state->nexthard; 254 if (idle) { 255 hardfreq = (u_int)hz / 2; 256 if (tc_min_ticktock_freq > 2 257 #ifdef SMP 258 && curcpu == CPU_FIRST() 259 #endif 260 ) 261 hardfreq = hz / tc_min_ticktock_freq; 262 if (hardfreq > 1) 263 event += tick_sbt * (hardfreq - 1); 264 } 265 /* Handle callout events. */ 266 if (event > state->nextcall) 267 event = state->nextcall; 268 if (!idle) { /* If CPU is active - handle other types of events. */ 269 if (event > state->nextstat) 270 event = state->nextstat; 271 if (profiling && event > state->nextprof) 272 event = state->nextprof; 273 } 274 #ifdef KDTRACE_HOOKS 275 if (event > state->nextcyc) 276 event = state->nextcyc; 277 #endif 278 return (event); 279 } 280 281 /* 282 * Schedule binuptime of the next event on all CPUs. 283 */ 284 static sbintime_t 285 getnextevent(void) 286 { 287 struct pcpu_state *state; 288 sbintime_t event; 289 #ifdef SMP 290 int cpu; 291 #endif 292 int c; 293 294 state = DPCPU_PTR(timerstate); 295 event = state->nextevent; 296 c = -1; 297 #ifdef SMP 298 if ((timer->et_flags & ET_FLAGS_PERCPU) == 0) { 299 CPU_FOREACH(cpu) { 300 state = DPCPU_ID_PTR(cpu, timerstate); 301 if (event > state->nextevent) { 302 event = state->nextevent; 303 c = cpu; 304 } 305 } 306 } 307 #endif 308 CTR4(KTR_SPARE2, "next at %d: next %d.%08x by %d", 309 curcpu, (int)(event >> 32), (u_int)(event & 0xffffffff), c); 310 return (event); 311 } 312 313 /* Hardware timer callback function. */ 314 static void 315 timercb(struct eventtimer *et, void *arg) 316 { 317 sbintime_t now; 318 sbintime_t *next; 319 struct pcpu_state *state; 320 #ifdef SMP 321 int cpu, bcast; 322 #endif 323 324 /* Do not touch anything if somebody reconfiguring timers. */ 325 if (busy) 326 return; 327 /* Update present and next tick times. */ 328 state = DPCPU_PTR(timerstate); 329 if (et->et_flags & ET_FLAGS_PERCPU) { 330 next = &state->nexttick; 331 } else 332 next = &nexttick; 333 now = sbinuptime(); 334 if (periodic) 335 *next = now + timerperiod; 336 else 337 *next = -1; /* Next tick is not scheduled yet. */ 338 state->now = now; 339 CTR3(KTR_SPARE2, "intr at %d: now %d.%08x", 340 curcpu, (int)(now >> 32), (u_int)(now & 0xffffffff)); 341 342 #ifdef SMP 343 /* Prepare broadcasting to other CPUs for non-per-CPU timers. */ 344 bcast = 0; 345 if ((et->et_flags & ET_FLAGS_PERCPU) == 0 && smp_started) { 346 CPU_FOREACH(cpu) { 347 state = DPCPU_ID_PTR(cpu, timerstate); 348 ET_HW_LOCK(state); 349 state->now = now; 350 if (now >= state->nextevent) { 351 state->nextevent += SBT_1S; 352 if (curcpu != cpu) { 353 state->ipi = 1; 354 bcast = 1; 355 } 356 } 357 ET_HW_UNLOCK(state); 358 } 359 } 360 #endif 361 362 /* Handle events for this time on this CPU. */ 363 handleevents(now, 0); 364 365 #ifdef SMP 366 /* Broadcast interrupt to other CPUs for non-per-CPU timers. */ 367 if (bcast) { 368 CPU_FOREACH(cpu) { 369 if (curcpu == cpu) 370 continue; 371 state = DPCPU_ID_PTR(cpu, timerstate); 372 if (state->ipi) { 373 state->ipi = 0; 374 ipi_cpu(cpu, IPI_HARDCLOCK); 375 } 376 } 377 } 378 #endif 379 } 380 381 /* 382 * Load new value into hardware timer. 383 */ 384 static void 385 loadtimer(sbintime_t now, int start) 386 { 387 struct pcpu_state *state; 388 sbintime_t new; 389 sbintime_t *next; 390 uint64_t tmp; 391 int eq; 392 393 if (timer->et_flags & ET_FLAGS_PERCPU) { 394 state = DPCPU_PTR(timerstate); 395 next = &state->nexttick; 396 } else 397 next = &nexttick; 398 if (periodic) { 399 if (start) { 400 /* 401 * Try to start all periodic timers aligned 402 * to period to make events synchronous. 403 */ 404 tmp = now % timerperiod; 405 new = timerperiod - tmp; 406 if (new < tmp) /* Left less then passed. */ 407 new += timerperiod; 408 CTR5(KTR_SPARE2, "load p at %d: now %d.%08x first in %d.%08x", 409 curcpu, (int)(now >> 32), (u_int)(now & 0xffffffff), 410 (int)(new >> 32), (u_int)(new & 0xffffffff)); 411 *next = new + now; 412 et_start(timer, new, timerperiod); 413 } 414 } else { 415 new = getnextevent(); 416 eq = (new == *next); 417 CTR4(KTR_SPARE2, "load at %d: next %d.%08x eq %d", 418 curcpu, (int)(new >> 32), (u_int)(new & 0xffffffff), eq); 419 if (!eq) { 420 *next = new; 421 et_start(timer, new - now, 0); 422 } 423 } 424 } 425 426 /* 427 * Prepare event timer parameters after configuration changes. 428 */ 429 static void 430 setuptimer(void) 431 { 432 int freq; 433 434 if (periodic && (timer->et_flags & ET_FLAGS_PERIODIC) == 0) 435 periodic = 0; 436 else if (!periodic && (timer->et_flags & ET_FLAGS_ONESHOT) == 0) 437 periodic = 1; 438 singlemul = MIN(MAX(singlemul, 1), 20); 439 freq = hz * singlemul; 440 while (freq < (profiling ? profhz : stathz)) 441 freq += hz; 442 freq = round_freq(timer, freq); 443 timerperiod = SBT_1S / freq; 444 } 445 446 /* 447 * Reconfigure specified per-CPU timer on other CPU. Called from IPI handler. 448 */ 449 static int 450 doconfigtimer(void) 451 { 452 sbintime_t now; 453 struct pcpu_state *state; 454 455 state = DPCPU_PTR(timerstate); 456 switch (atomic_load_acq_int(&state->action)) { 457 case 1: 458 now = sbinuptime(); 459 ET_HW_LOCK(state); 460 loadtimer(now, 1); 461 ET_HW_UNLOCK(state); 462 state->handle = 0; 463 atomic_store_rel_int(&state->action, 0); 464 return (1); 465 case 2: 466 ET_HW_LOCK(state); 467 et_stop(timer); 468 ET_HW_UNLOCK(state); 469 state->handle = 0; 470 atomic_store_rel_int(&state->action, 0); 471 return (1); 472 } 473 if (atomic_readandclear_int(&state->handle) && !busy) { 474 now = sbinuptime(); 475 handleevents(now, 0); 476 return (1); 477 } 478 return (0); 479 } 480 481 /* 482 * Reconfigure specified timer. 483 * For per-CPU timers use IPI to make other CPUs to reconfigure. 484 */ 485 static void 486 configtimer(int start) 487 { 488 sbintime_t now, next; 489 struct pcpu_state *state; 490 int cpu; 491 492 if (start) { 493 setuptimer(); 494 now = sbinuptime(); 495 } else 496 now = 0; 497 critical_enter(); 498 ET_HW_LOCK(DPCPU_PTR(timerstate)); 499 if (start) { 500 /* Initialize time machine parameters. */ 501 next = now + timerperiod; 502 if (periodic) 503 nexttick = next; 504 else 505 nexttick = -1; 506 CPU_FOREACH(cpu) { 507 state = DPCPU_ID_PTR(cpu, timerstate); 508 state->now = now; 509 if (!smp_started && cpu != CPU_FIRST()) 510 state->nextevent = SBT_MAX; 511 else 512 state->nextevent = next; 513 if (periodic) 514 state->nexttick = next; 515 else 516 state->nexttick = -1; 517 state->nexthard = next; 518 state->nextstat = next; 519 state->nextprof = next; 520 state->nextcall = next; 521 state->nextcallopt = next; 522 hardclock_sync(cpu); 523 } 524 busy = 0; 525 /* Start global timer or per-CPU timer of this CPU. */ 526 loadtimer(now, 1); 527 } else { 528 busy = 1; 529 /* Stop global timer or per-CPU timer of this CPU. */ 530 et_stop(timer); 531 } 532 ET_HW_UNLOCK(DPCPU_PTR(timerstate)); 533 #ifdef SMP 534 /* If timer is global or there is no other CPUs yet - we are done. */ 535 if ((timer->et_flags & ET_FLAGS_PERCPU) == 0 || !smp_started) { 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 #ifdef KDTRACE_HOOKS 599 state->nextcyc = SBT_MAX; 600 #endif 601 state->nextcall = SBT_MAX; 602 state->nextcallopt = SBT_MAX; 603 } 604 periodic = want_periodic; 605 /* Grab requested timer or the best of present. */ 606 if (timername[0]) 607 timer = et_find(timername, 0, 0); 608 if (timer == NULL && periodic) { 609 timer = et_find(NULL, 610 ET_FLAGS_PERIODIC, ET_FLAGS_PERIODIC); 611 } 612 if (timer == NULL) { 613 timer = et_find(NULL, 614 ET_FLAGS_ONESHOT, ET_FLAGS_ONESHOT); 615 } 616 if (timer == NULL && !periodic) { 617 timer = et_find(NULL, 618 ET_FLAGS_PERIODIC, ET_FLAGS_PERIODIC); 619 } 620 if (timer == NULL) 621 panic("No usable event timer found!"); 622 et_init(timer, timercb, NULL, NULL); 623 624 /* Adapt to timer capabilities. */ 625 if (periodic && (timer->et_flags & ET_FLAGS_PERIODIC) == 0) 626 periodic = 0; 627 else if (!periodic && (timer->et_flags & ET_FLAGS_ONESHOT) == 0) 628 periodic = 1; 629 if (timer->et_flags & ET_FLAGS_C3STOP) 630 cpu_disable_deep_sleep++; 631 632 /* 633 * We honor the requested 'hz' value. 634 * We want to run stathz in the neighborhood of 128hz. 635 * We would like profhz to run as often as possible. 636 */ 637 if (singlemul <= 0 || singlemul > 20) { 638 if (hz >= 1500 || (hz % 128) == 0) 639 singlemul = 1; 640 else if (hz >= 750) 641 singlemul = 2; 642 else 643 singlemul = 4; 644 } 645 if (periodic) { 646 base = round_freq(timer, hz * singlemul); 647 singlemul = max((base + hz / 2) / hz, 1); 648 hz = (base + singlemul / 2) / singlemul; 649 if (base <= 128) 650 stathz = base; 651 else { 652 div = base / 128; 653 if (div >= singlemul && (div % singlemul) == 0) 654 div++; 655 stathz = base / div; 656 } 657 profhz = stathz; 658 while ((profhz + stathz) <= 128 * 64) 659 profhz += stathz; 660 profhz = round_freq(timer, profhz); 661 } else { 662 hz = round_freq(timer, hz); 663 stathz = round_freq(timer, 127); 664 profhz = round_freq(timer, stathz * 64); 665 } 666 tick = 1000000 / hz; 667 tick_sbt = SBT_1S / hz; 668 tick_bt = sbttobt(tick_sbt); 669 statperiod = SBT_1S / stathz; 670 profperiod = SBT_1S / profhz; 671 ET_LOCK(); 672 configtimer(1); 673 ET_UNLOCK(); 674 } 675 676 /* 677 * Start per-CPU event timers on APs. 678 */ 679 void 680 cpu_initclocks_ap(void) 681 { 682 sbintime_t now; 683 struct pcpu_state *state; 684 struct thread *td; 685 686 state = DPCPU_PTR(timerstate); 687 now = sbinuptime(); 688 ET_HW_LOCK(state); 689 state->now = now; 690 hardclock_sync(curcpu); 691 spinlock_enter(); 692 ET_HW_UNLOCK(state); 693 td = curthread; 694 td->td_intr_nesting_level++; 695 handleevents(state->now, 2); 696 td->td_intr_nesting_level--; 697 spinlock_exit(); 698 } 699 700 /* 701 * Switch to profiling clock rates. 702 */ 703 void 704 cpu_startprofclock(void) 705 { 706 707 ET_LOCK(); 708 if (profiling == 0) { 709 if (periodic) { 710 configtimer(0); 711 profiling = 1; 712 configtimer(1); 713 } else 714 profiling = 1; 715 } else 716 profiling++; 717 ET_UNLOCK(); 718 } 719 720 /* 721 * Switch to regular clock rates. 722 */ 723 void 724 cpu_stopprofclock(void) 725 { 726 727 ET_LOCK(); 728 if (profiling == 1) { 729 if (periodic) { 730 configtimer(0); 731 profiling = 0; 732 configtimer(1); 733 } else 734 profiling = 0; 735 } else 736 profiling--; 737 ET_UNLOCK(); 738 } 739 740 /* 741 * Switch to idle mode (all ticks handled). 742 */ 743 sbintime_t 744 cpu_idleclock(void) 745 { 746 sbintime_t now, t; 747 struct pcpu_state *state; 748 749 if (idletick || busy || 750 (periodic && (timer->et_flags & ET_FLAGS_PERCPU)) 751 #ifdef DEVICE_POLLING 752 || curcpu == CPU_FIRST() 753 #endif 754 ) 755 return (-1); 756 state = DPCPU_PTR(timerstate); 757 if (periodic) 758 now = state->now; 759 else 760 now = sbinuptime(); 761 CTR3(KTR_SPARE2, "idle at %d: now %d.%08x", 762 curcpu, (int)(now >> 32), (u_int)(now & 0xffffffff)); 763 t = getnextcpuevent(1); 764 ET_HW_LOCK(state); 765 state->idle = 1; 766 state->nextevent = t; 767 if (!periodic) 768 loadtimer(now, 0); 769 ET_HW_UNLOCK(state); 770 return (MAX(t - now, 0)); 771 } 772 773 /* 774 * Switch to active mode (skip empty ticks). 775 */ 776 void 777 cpu_activeclock(void) 778 { 779 sbintime_t now; 780 struct pcpu_state *state; 781 struct thread *td; 782 783 state = DPCPU_PTR(timerstate); 784 if (state->idle == 0 || busy) 785 return; 786 if (periodic) 787 now = state->now; 788 else 789 now = sbinuptime(); 790 CTR3(KTR_SPARE2, "active at %d: now %d.%08x", 791 curcpu, (int)(now >> 32), (u_int)(now & 0xffffffff)); 792 spinlock_enter(); 793 td = curthread; 794 td->td_intr_nesting_level++; 795 handleevents(now, 1); 796 td->td_intr_nesting_level--; 797 spinlock_exit(); 798 } 799 800 /* 801 * Change the frequency of the given timer. This changes et->et_frequency and 802 * if et is the active timer it reconfigures the timer on all CPUs. This is 803 * intended to be a private interface for the use of et_change_frequency() only. 804 */ 805 void 806 cpu_et_frequency(struct eventtimer *et, uint64_t newfreq) 807 { 808 809 ET_LOCK(); 810 if (et == timer) { 811 configtimer(0); 812 et->et_frequency = newfreq; 813 configtimer(1); 814 } else 815 et->et_frequency = newfreq; 816 ET_UNLOCK(); 817 } 818 819 #ifdef KDTRACE_HOOKS 820 void 821 clocksource_cyc_set(const struct bintime *bt) 822 { 823 sbintime_t now, t; 824 struct pcpu_state *state; 825 826 /* Do not touch anything if somebody reconfiguring timers. */ 827 if (busy) 828 return; 829 t = bttosbt(*bt); 830 state = DPCPU_PTR(timerstate); 831 if (periodic) 832 now = state->now; 833 else 834 now = sbinuptime(); 835 836 CTR5(KTR_SPARE2, "set_cyc at %d: now %d.%08x t %d.%08x", 837 curcpu, (int)(now >> 32), (u_int)(now & 0xffffffff), 838 (int)(t >> 32), (u_int)(t & 0xffffffff)); 839 840 ET_HW_LOCK(state); 841 if (t == state->nextcyc) 842 goto done; 843 state->nextcyc = t; 844 if (t >= state->nextevent) 845 goto done; 846 state->nextevent = t; 847 if (!periodic) 848 loadtimer(now, 0); 849 done: 850 ET_HW_UNLOCK(state); 851 } 852 #endif 853 854 void 855 cpu_new_callout(int cpu, sbintime_t bt, sbintime_t bt_opt) 856 { 857 struct pcpu_state *state; 858 859 /* Do not touch anything if somebody reconfiguring timers. */ 860 if (busy) 861 return; 862 CTR6(KTR_SPARE2, "new co at %d: on %d at %d.%08x - %d.%08x", 863 curcpu, cpu, (int)(bt_opt >> 32), (u_int)(bt_opt & 0xffffffff), 864 (int)(bt >> 32), (u_int)(bt & 0xffffffff)); 865 state = DPCPU_ID_PTR(cpu, timerstate); 866 ET_HW_LOCK(state); 867 868 /* 869 * If there is callout time already set earlier -- do nothing. 870 * This check may appear redundant because we check already in 871 * callout_process() but this double check guarantees we're safe 872 * with respect to race conditions between interrupts execution 873 * and scheduling. 874 */ 875 state->nextcallopt = bt_opt; 876 if (bt >= state->nextcall) 877 goto done; 878 state->nextcall = bt; 879 /* If there is some other event set earlier -- do nothing. */ 880 if (bt >= state->nextevent) 881 goto done; 882 state->nextevent = bt; 883 /* If timer is periodic -- there is nothing to reprogram. */ 884 if (periodic) 885 goto done; 886 /* If timer is global or of the current CPU -- reprogram it. */ 887 if ((timer->et_flags & ET_FLAGS_PERCPU) == 0 || cpu == curcpu) { 888 loadtimer(sbinuptime(), 0); 889 done: 890 ET_HW_UNLOCK(state); 891 return; 892 } 893 /* Otherwise make other CPU to reprogram it. */ 894 state->handle = 1; 895 ET_HW_UNLOCK(state); 896 #ifdef SMP 897 ipi_cpu(cpu, IPI_HARDCLOCK); 898 #endif 899 } 900 901 /* 902 * Report or change the active event timers hardware. 903 */ 904 static int 905 sysctl_kern_eventtimer_timer(SYSCTL_HANDLER_ARGS) 906 { 907 char buf[32]; 908 struct eventtimer *et; 909 int error; 910 911 ET_LOCK(); 912 et = timer; 913 snprintf(buf, sizeof(buf), "%s", et->et_name); 914 ET_UNLOCK(); 915 error = sysctl_handle_string(oidp, buf, sizeof(buf), req); 916 ET_LOCK(); 917 et = timer; 918 if (error != 0 || req->newptr == NULL || 919 strcasecmp(buf, et->et_name) == 0) { 920 ET_UNLOCK(); 921 return (error); 922 } 923 et = et_find(buf, 0, 0); 924 if (et == NULL) { 925 ET_UNLOCK(); 926 return (ENOENT); 927 } 928 configtimer(0); 929 et_free(timer); 930 if (et->et_flags & ET_FLAGS_C3STOP) 931 cpu_disable_deep_sleep++; 932 if (timer->et_flags & ET_FLAGS_C3STOP) 933 cpu_disable_deep_sleep--; 934 periodic = want_periodic; 935 timer = et; 936 et_init(timer, timercb, NULL, NULL); 937 configtimer(1); 938 ET_UNLOCK(); 939 return (error); 940 } 941 SYSCTL_PROC(_kern_eventtimer, OID_AUTO, timer, 942 CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_MPSAFE, 943 0, 0, sysctl_kern_eventtimer_timer, "A", "Chosen event timer"); 944 945 /* 946 * Report or change the active event timer periodicity. 947 */ 948 static int 949 sysctl_kern_eventtimer_periodic(SYSCTL_HANDLER_ARGS) 950 { 951 int error, val; 952 953 val = periodic; 954 error = sysctl_handle_int(oidp, &val, 0, req); 955 if (error != 0 || req->newptr == NULL) 956 return (error); 957 ET_LOCK(); 958 configtimer(0); 959 periodic = want_periodic = val; 960 configtimer(1); 961 ET_UNLOCK(); 962 return (error); 963 } 964 SYSCTL_PROC(_kern_eventtimer, OID_AUTO, periodic, 965 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, 966 0, 0, sysctl_kern_eventtimer_periodic, "I", "Enable event timer periodic mode"); 967