1 /* $OpenBSD: sched_bsd.c,v 1.89 2023/10/17 00:04:02 cheloha Exp $ */ 2 /* $NetBSD: kern_synch.c,v 1.37 1996/04/22 01:38:37 christos Exp $ */ 3 4 /*- 5 * Copyright (c) 1982, 1986, 1990, 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * (c) UNIX System Laboratories, Inc. 8 * All or some portions of this file are derived from material licensed 9 * to the University of California by American Telephone and Telegraph 10 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 11 * the permission of UNIX System Laboratories, Inc. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * @(#)kern_synch.c 8.6 (Berkeley) 1/21/94 38 */ 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/clockintr.h> 43 #include <sys/proc.h> 44 #include <sys/kernel.h> 45 #include <sys/malloc.h> 46 #include <sys/resourcevar.h> 47 #include <uvm/uvm_extern.h> 48 #include <sys/sched.h> 49 #include <sys/timeout.h> 50 #include <sys/smr.h> 51 #include <sys/tracepoint.h> 52 53 #ifdef KTRACE 54 #include <sys/ktrace.h> 55 #endif 56 57 uint64_t roundrobin_period; /* [I] roundrobin period (ns) */ 58 int lbolt; /* once a second sleep address */ 59 60 #ifdef MULTIPROCESSOR 61 struct __mp_lock sched_lock; 62 #endif 63 64 void update_loadavg(void *); 65 void schedcpu(void *); 66 uint32_t decay_aftersleep(uint32_t, uint32_t); 67 68 extern struct cpuset sched_idle_cpus; 69 70 /* 71 * constants for averages over 1, 5, and 15 minutes when sampling at 72 * 5 second intervals. 73 */ 74 static const fixpt_t cexp[3] = { 75 0.9200444146293232 * FSCALE, /* exp(-1/12) */ 76 0.9834714538216174 * FSCALE, /* exp(-1/60) */ 77 0.9944598480048967 * FSCALE, /* exp(-1/180) */ 78 }; 79 80 struct loadavg averunnable; 81 82 /* 83 * Force switch among equal priority processes every 100ms. 84 */ 85 void 86 roundrobin(struct clockrequest *cr, void *cf, void *arg) 87 { 88 uint64_t count; 89 struct cpu_info *ci = curcpu(); 90 struct schedstate_percpu *spc = &ci->ci_schedstate; 91 92 count = clockrequest_advance(cr, roundrobin_period); 93 94 if (ci->ci_curproc != NULL) { 95 if (spc->spc_schedflags & SPCF_SEENRR || count >= 2) { 96 /* 97 * The process has already been through a roundrobin 98 * without switching and may be hogging the CPU. 99 * Indicate that the process should yield. 100 */ 101 atomic_setbits_int(&spc->spc_schedflags, 102 SPCF_SEENRR | SPCF_SHOULDYIELD); 103 } else { 104 atomic_setbits_int(&spc->spc_schedflags, 105 SPCF_SEENRR); 106 } 107 } 108 109 if (spc->spc_nrun || spc->spc_schedflags & SPCF_SHOULDYIELD) 110 need_resched(ci); 111 } 112 113 114 115 /* 116 * update_loadav: compute a tenex style load average of a quantity on 117 * 1, 5, and 15 minute intervals. 118 */ 119 void 120 update_loadavg(void *unused) 121 { 122 static struct timeout to = TIMEOUT_INITIALIZER(update_loadavg, NULL); 123 CPU_INFO_ITERATOR cii; 124 struct cpu_info *ci; 125 u_int i, nrun = 0; 126 127 CPU_INFO_FOREACH(cii, ci) { 128 if (!cpuset_isset(&sched_idle_cpus, ci)) 129 nrun++; 130 nrun += ci->ci_schedstate.spc_nrun; 131 } 132 133 for (i = 0; i < 3; i++) { 134 averunnable.ldavg[i] = (cexp[i] * averunnable.ldavg[i] + 135 nrun * FSCALE * (FSCALE - cexp[i])) >> FSHIFT; 136 } 137 138 timeout_add_sec(&to, 5); 139 } 140 141 /* 142 * Constants for digital decay and forget: 143 * 90% of (p_estcpu) usage in 5 * loadav time 144 * 95% of (p_pctcpu) usage in 60 seconds (load insensitive) 145 * Note that, as ps(1) mentions, this can let percentages 146 * total over 100% (I've seen 137.9% for 3 processes). 147 * 148 * Note that hardclock updates p_estcpu and p_cpticks independently. 149 * 150 * We wish to decay away 90% of p_estcpu in (5 * loadavg) seconds. 151 * That is, the system wants to compute a value of decay such 152 * that the following for loop: 153 * for (i = 0; i < (5 * loadavg); i++) 154 * p_estcpu *= decay; 155 * will compute 156 * p_estcpu *= 0.1; 157 * for all values of loadavg: 158 * 159 * Mathematically this loop can be expressed by saying: 160 * decay ** (5 * loadavg) ~= .1 161 * 162 * The system computes decay as: 163 * decay = (2 * loadavg) / (2 * loadavg + 1) 164 * 165 * We wish to prove that the system's computation of decay 166 * will always fulfill the equation: 167 * decay ** (5 * loadavg) ~= .1 168 * 169 * If we compute b as: 170 * b = 2 * loadavg 171 * then 172 * decay = b / (b + 1) 173 * 174 * We now need to prove two things: 175 * 1) Given factor ** (5 * loadavg) ~= .1, prove factor == b/(b+1) 176 * 2) Given b/(b+1) ** power ~= .1, prove power == (5 * loadavg) 177 * 178 * Facts: 179 * For x close to zero, exp(x) =~ 1 + x, since 180 * exp(x) = 0! + x**1/1! + x**2/2! + ... . 181 * therefore exp(-1/b) =~ 1 - (1/b) = (b-1)/b. 182 * For x close to zero, ln(1+x) =~ x, since 183 * ln(1+x) = x - x**2/2 + x**3/3 - ... -1 < x < 1 184 * therefore ln(b/(b+1)) = ln(1 - 1/(b+1)) =~ -1/(b+1). 185 * ln(.1) =~ -2.30 186 * 187 * Proof of (1): 188 * Solve (factor)**(power) =~ .1 given power (5*loadav): 189 * solving for factor, 190 * ln(factor) =~ (-2.30/5*loadav), or 191 * factor =~ exp(-1/((5/2.30)*loadav)) =~ exp(-1/(2*loadav)) = 192 * exp(-1/b) =~ (b-1)/b =~ b/(b+1). QED 193 * 194 * Proof of (2): 195 * Solve (factor)**(power) =~ .1 given factor == (b/(b+1)): 196 * solving for power, 197 * power*ln(b/(b+1)) =~ -2.30, or 198 * power =~ 2.3 * (b + 1) = 4.6*loadav + 2.3 =~ 5*loadav. QED 199 * 200 * Actual power values for the implemented algorithm are as follows: 201 * loadav: 1 2 3 4 202 * power: 5.68 10.32 14.94 19.55 203 */ 204 205 /* calculations for digital decay to forget 90% of usage in 5*loadav sec */ 206 #define loadfactor(loadav) (2 * (loadav)) 207 #define decay_cpu(loadfac, cpu) (((loadfac) * (cpu)) / ((loadfac) + FSCALE)) 208 209 /* decay 95% of `p_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */ 210 fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */ 211 212 /* 213 * If `ccpu' is not equal to `exp(-1/20)' and you still want to use the 214 * faster/more-accurate formula, you'll have to estimate CCPU_SHIFT below 215 * and possibly adjust FSHIFT in "param.h" so that (FSHIFT >= CCPU_SHIFT). 216 * 217 * To estimate CCPU_SHIFT for exp(-1/20), the following formula was used: 218 * 1 - exp(-1/20) ~= 0.0487 ~= 0.0488 == 1 (fixed pt, *11* bits). 219 * 220 * If you don't want to bother with the faster/more-accurate formula, you 221 * can set CCPU_SHIFT to (FSHIFT + 1) which will use a slower/less-accurate 222 * (more general) method of calculating the %age of CPU used by a process. 223 */ 224 #define CCPU_SHIFT 11 225 226 /* 227 * Recompute process priorities, every second. 228 */ 229 void 230 schedcpu(void *unused) 231 { 232 static struct timeout to = TIMEOUT_INITIALIZER(schedcpu, NULL); 233 fixpt_t loadfac = loadfactor(averunnable.ldavg[0]); 234 struct proc *p; 235 int s; 236 unsigned int newcpu; 237 238 LIST_FOREACH(p, &allproc, p_list) { 239 /* 240 * Idle threads are never placed on the runqueue, 241 * therefore computing their priority is pointless. 242 */ 243 if (p->p_cpu != NULL && 244 p->p_cpu->ci_schedstate.spc_idleproc == p) 245 continue; 246 /* 247 * Increment sleep time (if sleeping). We ignore overflow. 248 */ 249 if (p->p_stat == SSLEEP || p->p_stat == SSTOP) 250 p->p_slptime++; 251 p->p_pctcpu = (p->p_pctcpu * ccpu) >> FSHIFT; 252 /* 253 * If the process has slept the entire second, 254 * stop recalculating its priority until it wakes up. 255 */ 256 if (p->p_slptime > 1) 257 continue; 258 SCHED_LOCK(s); 259 /* 260 * p_pctcpu is only for diagnostic tools such as ps. 261 */ 262 #if (FSHIFT >= CCPU_SHIFT) 263 p->p_pctcpu += (stathz == 100)? 264 ((fixpt_t) p->p_cpticks) << (FSHIFT - CCPU_SHIFT): 265 100 * (((fixpt_t) p->p_cpticks) 266 << (FSHIFT - CCPU_SHIFT)) / stathz; 267 #else 268 p->p_pctcpu += ((FSCALE - ccpu) * 269 (p->p_cpticks * FSCALE / stathz)) >> FSHIFT; 270 #endif 271 p->p_cpticks = 0; 272 newcpu = (u_int) decay_cpu(loadfac, p->p_estcpu); 273 setpriority(p, newcpu, p->p_p->ps_nice); 274 275 if (p->p_stat == SRUN && 276 (p->p_runpri / SCHED_PPQ) != (p->p_usrpri / SCHED_PPQ)) { 277 remrunqueue(p); 278 setrunqueue(p->p_cpu, p, p->p_usrpri); 279 } 280 SCHED_UNLOCK(s); 281 } 282 wakeup(&lbolt); 283 timeout_add_sec(&to, 1); 284 } 285 286 /* 287 * Recalculate the priority of a process after it has slept for a while. 288 * For all load averages >= 1 and max p_estcpu of 255, sleeping for at 289 * least six times the loadfactor will decay p_estcpu to zero. 290 */ 291 uint32_t 292 decay_aftersleep(uint32_t estcpu, uint32_t slptime) 293 { 294 fixpt_t loadfac = loadfactor(averunnable.ldavg[0]); 295 uint32_t newcpu; 296 297 if (slptime > 5 * loadfac) 298 newcpu = 0; 299 else { 300 newcpu = estcpu; 301 slptime--; /* the first time was done in schedcpu */ 302 while (newcpu && --slptime) 303 newcpu = decay_cpu(loadfac, newcpu); 304 305 } 306 307 return (newcpu); 308 } 309 310 /* 311 * General yield call. Puts the current process back on its run queue and 312 * performs a voluntary context switch. 313 */ 314 void 315 yield(void) 316 { 317 struct proc *p = curproc; 318 int s; 319 320 SCHED_LOCK(s); 321 setrunqueue(p->p_cpu, p, p->p_usrpri); 322 p->p_ru.ru_nvcsw++; 323 mi_switch(); 324 SCHED_UNLOCK(s); 325 } 326 327 /* 328 * General preemption call. Puts the current process back on its run queue 329 * and performs an involuntary context switch. If a process is supplied, 330 * we switch to that process. Otherwise, we use the normal process selection 331 * criteria. 332 */ 333 void 334 preempt(void) 335 { 336 struct proc *p = curproc; 337 int s; 338 339 SCHED_LOCK(s); 340 setrunqueue(p->p_cpu, p, p->p_usrpri); 341 p->p_ru.ru_nivcsw++; 342 mi_switch(); 343 SCHED_UNLOCK(s); 344 } 345 346 void 347 mi_switch(void) 348 { 349 struct schedstate_percpu *spc = &curcpu()->ci_schedstate; 350 struct proc *p = curproc; 351 struct proc *nextproc; 352 struct process *pr = p->p_p; 353 struct timespec ts; 354 #ifdef MULTIPROCESSOR 355 int hold_count; 356 int sched_count; 357 #endif 358 359 assertwaitok(); 360 KASSERT(p->p_stat != SONPROC); 361 362 SCHED_ASSERT_LOCKED(); 363 364 #ifdef MULTIPROCESSOR 365 /* 366 * Release the kernel_lock, as we are about to yield the CPU. 367 */ 368 sched_count = __mp_release_all_but_one(&sched_lock); 369 if (_kernel_lock_held()) 370 hold_count = __mp_release_all(&kernel_lock); 371 else 372 hold_count = 0; 373 #endif 374 375 /* 376 * Compute the amount of time during which the current 377 * process was running, and add that to its total so far. 378 */ 379 nanouptime(&ts); 380 if (timespeccmp(&ts, &spc->spc_runtime, <)) { 381 #if 0 382 printf("uptime is not monotonic! " 383 "ts=%lld.%09lu, runtime=%lld.%09lu\n", 384 (long long)tv.tv_sec, tv.tv_nsec, 385 (long long)spc->spc_runtime.tv_sec, 386 spc->spc_runtime.tv_nsec); 387 #endif 388 timespecclear(&ts); 389 } else { 390 timespecsub(&ts, &spc->spc_runtime, &ts); 391 } 392 393 /* add the time counts for this thread to the process's total */ 394 tuagg_locked(pr, p, &ts); 395 396 /* Stop any optional clock interrupts. */ 397 if (ISSET(spc->spc_schedflags, SPCF_ITIMER)) { 398 atomic_clearbits_int(&spc->spc_schedflags, SPCF_ITIMER); 399 clockintr_cancel(spc->spc_itimer); 400 } 401 if (ISSET(spc->spc_schedflags, SPCF_PROFCLOCK)) { 402 atomic_clearbits_int(&spc->spc_schedflags, SPCF_PROFCLOCK); 403 clockintr_cancel(spc->spc_profclock); 404 } 405 406 /* 407 * Process is about to yield the CPU; clear the appropriate 408 * scheduling flags. 409 */ 410 atomic_clearbits_int(&spc->spc_schedflags, SPCF_SWITCHCLEAR); 411 412 nextproc = sched_chooseproc(); 413 414 if (p != nextproc) { 415 uvmexp.swtch++; 416 TRACEPOINT(sched, off__cpu, nextproc->p_tid + THREAD_PID_OFFSET, 417 nextproc->p_p->ps_pid); 418 cpu_switchto(p, nextproc); 419 TRACEPOINT(sched, on__cpu, NULL); 420 } else { 421 TRACEPOINT(sched, remain__cpu, NULL); 422 p->p_stat = SONPROC; 423 } 424 425 clear_resched(curcpu()); 426 427 SCHED_ASSERT_LOCKED(); 428 429 /* 430 * To preserve lock ordering, we need to release the sched lock 431 * and grab it after we grab the big lock. 432 * In the future, when the sched lock isn't recursive, we'll 433 * just release it here. 434 */ 435 #ifdef MULTIPROCESSOR 436 __mp_unlock(&sched_lock); 437 #endif 438 439 SCHED_ASSERT_UNLOCKED(); 440 441 smr_idle(); 442 443 /* 444 * We're running again; record our new start time. We might 445 * be running on a new CPU now, so refetch the schedstate_percpu 446 * pointer. 447 */ 448 KASSERT(p->p_cpu == curcpu()); 449 spc = &p->p_cpu->ci_schedstate; 450 451 /* Start any optional clock interrupts needed by the thread. */ 452 if (ISSET(p->p_p->ps_flags, PS_ITIMER)) { 453 atomic_setbits_int(&spc->spc_schedflags, SPCF_ITIMER); 454 clockintr_advance(spc->spc_itimer, hardclock_period); 455 } 456 if (ISSET(p->p_p->ps_flags, PS_PROFIL)) { 457 atomic_setbits_int(&spc->spc_schedflags, SPCF_PROFCLOCK); 458 clockintr_advance(spc->spc_profclock, profclock_period); 459 } 460 461 nanouptime(&spc->spc_runtime); 462 463 #ifdef MULTIPROCESSOR 464 /* 465 * Reacquire the kernel_lock now. We do this after we've 466 * released the scheduler lock to avoid deadlock, and before 467 * we reacquire the interlock and the scheduler lock. 468 */ 469 if (hold_count) 470 __mp_acquire_count(&kernel_lock, hold_count); 471 __mp_acquire_count(&sched_lock, sched_count + 1); 472 #endif 473 } 474 475 /* 476 * Change process state to be runnable, 477 * placing it on the run queue. 478 */ 479 void 480 setrunnable(struct proc *p) 481 { 482 struct process *pr = p->p_p; 483 u_char prio; 484 485 SCHED_ASSERT_LOCKED(); 486 487 switch (p->p_stat) { 488 case 0: 489 case SRUN: 490 case SONPROC: 491 case SDEAD: 492 case SIDL: 493 default: 494 panic("setrunnable"); 495 case SSTOP: 496 /* 497 * If we're being traced (possibly because someone attached us 498 * while we were stopped), check for a signal from the debugger. 499 */ 500 if ((pr->ps_flags & PS_TRACED) != 0 && pr->ps_xsig != 0) 501 atomic_setbits_int(&p->p_siglist, sigmask(pr->ps_xsig)); 502 prio = p->p_usrpri; 503 unsleep(p); 504 setrunqueue(NULL, p, prio); 505 break; 506 case SSLEEP: 507 prio = p->p_slppri; 508 unsleep(p); /* e.g. when sending signals */ 509 510 /* if not yet asleep, don't add to runqueue */ 511 if (ISSET(p->p_flag, P_WSLEEP)) 512 return; 513 setrunqueue(NULL, p, prio); 514 TRACEPOINT(sched, wakeup, p->p_tid + THREAD_PID_OFFSET, 515 p->p_p->ps_pid, CPU_INFO_UNIT(p->p_cpu)); 516 break; 517 } 518 if (p->p_slptime > 1) { 519 uint32_t newcpu; 520 521 newcpu = decay_aftersleep(p->p_estcpu, p->p_slptime); 522 setpriority(p, newcpu, pr->ps_nice); 523 } 524 p->p_slptime = 0; 525 } 526 527 /* 528 * Compute the priority of a process. 529 */ 530 void 531 setpriority(struct proc *p, uint32_t newcpu, uint8_t nice) 532 { 533 unsigned int newprio; 534 535 newprio = min((PUSER + newcpu + NICE_WEIGHT * (nice - NZERO)), MAXPRI); 536 537 SCHED_ASSERT_LOCKED(); 538 p->p_estcpu = newcpu; 539 p->p_usrpri = newprio; 540 } 541 542 /* 543 * We adjust the priority of the current process. The priority of a process 544 * gets worse as it accumulates CPU time. The cpu usage estimator (p_estcpu) 545 * is increased here. The formula for computing priorities (in kern_synch.c) 546 * will compute a different value each time p_estcpu increases. This can 547 * cause a switch, but unless the priority crosses a PPQ boundary the actual 548 * queue will not change. The cpu usage estimator ramps up quite quickly 549 * when the process is running (linearly), and decays away exponentially, at 550 * a rate which is proportionally slower when the system is busy. The basic 551 * principle is that the system will 90% forget that the process used a lot 552 * of CPU time in 5 * loadav seconds. This causes the system to favor 553 * processes which haven't run much recently, and to round-robin among other 554 * processes. 555 */ 556 void 557 schedclock(struct proc *p) 558 { 559 struct cpu_info *ci = curcpu(); 560 struct schedstate_percpu *spc = &ci->ci_schedstate; 561 uint32_t newcpu; 562 int s; 563 564 if (p == spc->spc_idleproc || spc->spc_spinning) 565 return; 566 567 SCHED_LOCK(s); 568 newcpu = ESTCPULIM(p->p_estcpu + 1); 569 setpriority(p, newcpu, p->p_p->ps_nice); 570 SCHED_UNLOCK(s); 571 } 572 573 void (*cpu_setperf)(int); 574 575 #define PERFPOL_MANUAL 0 576 #define PERFPOL_AUTO 1 577 #define PERFPOL_HIGH 2 578 int perflevel = 100; 579 int perfpolicy = PERFPOL_AUTO; 580 581 #ifndef SMALL_KERNEL 582 /* 583 * The code below handles CPU throttling. 584 */ 585 #include <sys/sysctl.h> 586 587 void setperf_auto(void *); 588 struct timeout setperf_to = TIMEOUT_INITIALIZER(setperf_auto, NULL); 589 extern int hw_power; 590 591 void 592 setperf_auto(void *v) 593 { 594 static uint64_t *idleticks, *totalticks; 595 static int downbeats; 596 int i, j = 0; 597 int speedup = 0; 598 CPU_INFO_ITERATOR cii; 599 struct cpu_info *ci; 600 uint64_t idle, total, allidle = 0, alltotal = 0; 601 602 if (perfpolicy != PERFPOL_AUTO) 603 return; 604 605 if (cpu_setperf == NULL) 606 return; 607 608 if (hw_power) { 609 speedup = 1; 610 goto faster; 611 } 612 613 if (!idleticks) 614 if (!(idleticks = mallocarray(ncpusfound, sizeof(*idleticks), 615 M_DEVBUF, M_NOWAIT | M_ZERO))) 616 return; 617 if (!totalticks) 618 if (!(totalticks = mallocarray(ncpusfound, sizeof(*totalticks), 619 M_DEVBUF, M_NOWAIT | M_ZERO))) { 620 free(idleticks, M_DEVBUF, 621 sizeof(*idleticks) * ncpusfound); 622 return; 623 } 624 CPU_INFO_FOREACH(cii, ci) { 625 if (!cpu_is_online(ci)) 626 continue; 627 total = 0; 628 for (i = 0; i < CPUSTATES; i++) { 629 total += ci->ci_schedstate.spc_cp_time[i]; 630 } 631 total -= totalticks[j]; 632 idle = ci->ci_schedstate.spc_cp_time[CP_IDLE] - idleticks[j]; 633 if (idle < total / 3) 634 speedup = 1; 635 alltotal += total; 636 allidle += idle; 637 idleticks[j] += idle; 638 totalticks[j] += total; 639 j++; 640 } 641 if (allidle < alltotal / 2) 642 speedup = 1; 643 if (speedup && downbeats < 5) 644 downbeats++; 645 646 if (speedup && perflevel != 100) { 647 faster: 648 perflevel = 100; 649 cpu_setperf(perflevel); 650 } else if (!speedup && perflevel != 0 && --downbeats <= 0) { 651 perflevel = 0; 652 cpu_setperf(perflevel); 653 } 654 655 timeout_add_msec(&setperf_to, 100); 656 } 657 658 int 659 sysctl_hwsetperf(void *oldp, size_t *oldlenp, void *newp, size_t newlen) 660 { 661 int err; 662 663 if (!cpu_setperf) 664 return EOPNOTSUPP; 665 666 if (perfpolicy != PERFPOL_MANUAL) 667 return sysctl_rdint(oldp, oldlenp, newp, perflevel); 668 669 err = sysctl_int_bounded(oldp, oldlenp, newp, newlen, 670 &perflevel, 0, 100); 671 if (err) 672 return err; 673 674 if (newp != NULL) 675 cpu_setperf(perflevel); 676 677 return 0; 678 } 679 680 int 681 sysctl_hwperfpolicy(void *oldp, size_t *oldlenp, void *newp, size_t newlen) 682 { 683 char policy[32]; 684 int err; 685 686 if (!cpu_setperf) 687 return EOPNOTSUPP; 688 689 switch (perfpolicy) { 690 case PERFPOL_MANUAL: 691 strlcpy(policy, "manual", sizeof(policy)); 692 break; 693 case PERFPOL_AUTO: 694 strlcpy(policy, "auto", sizeof(policy)); 695 break; 696 case PERFPOL_HIGH: 697 strlcpy(policy, "high", sizeof(policy)); 698 break; 699 default: 700 strlcpy(policy, "unknown", sizeof(policy)); 701 break; 702 } 703 704 if (newp == NULL) 705 return sysctl_rdstring(oldp, oldlenp, newp, policy); 706 707 err = sysctl_string(oldp, oldlenp, newp, newlen, policy, sizeof(policy)); 708 if (err) 709 return err; 710 if (strcmp(policy, "manual") == 0) 711 perfpolicy = PERFPOL_MANUAL; 712 else if (strcmp(policy, "auto") == 0) 713 perfpolicy = PERFPOL_AUTO; 714 else if (strcmp(policy, "high") == 0) 715 perfpolicy = PERFPOL_HIGH; 716 else 717 return EINVAL; 718 719 if (perfpolicy == PERFPOL_AUTO) { 720 timeout_add_msec(&setperf_to, 200); 721 } else if (perfpolicy == PERFPOL_HIGH) { 722 perflevel = 100; 723 cpu_setperf(perflevel); 724 } 725 return 0; 726 } 727 #endif 728 729 /* 730 * Start the scheduler's periodic timeouts. 731 */ 732 void 733 scheduler_start(void) 734 { 735 schedcpu(NULL); 736 update_loadavg(NULL); 737 738 #ifndef SMALL_KERNEL 739 if (perfpolicy == PERFPOL_AUTO) 740 timeout_add_msec(&setperf_to, 200); 741 #endif 742 } 743 744