Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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sys/kern/sched_4bsd.c
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1 /*- 2 * Copyright (c) 1982, 1986, 1990, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include "opt_hwpmc_hooks.h" 39 40 #define kse td_sched 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/kernel.h> 45 #include <sys/ktr.h> 46 #include <sys/lock.h> 47 #include <sys/kthread.h> 48 #include <sys/mutex.h> 49 #include <sys/proc.h> 50 #include <sys/resourcevar.h> 51 #include <sys/sched.h> 52 #include <sys/smp.h> 53 #include <sys/sysctl.h> 54 #include <sys/sx.h> 55 #include <sys/turnstile.h> 56 #include <machine/smp.h> 57 58 #ifdef HWPMC_HOOKS 59 #include <sys/pmckern.h> 60 #endif 61 62 /* 63 * INVERSE_ESTCPU_WEIGHT is only suitable for statclock() frequencies in 64 * the range 100-256 Hz (approximately). 65 */ 66 #define ESTCPULIM(e) \ 67 min((e), INVERSE_ESTCPU_WEIGHT * (NICE_WEIGHT * (PRIO_MAX - PRIO_MIN) - \ 68 RQ_PPQ) + INVERSE_ESTCPU_WEIGHT - 1) 69 #ifdef SMP 70 #define INVERSE_ESTCPU_WEIGHT (8 * smp_cpus) 71 #else 72 #define INVERSE_ESTCPU_WEIGHT 8 /* 1 / (priorities per estcpu level). */ 73 #endif 74 #define NICE_WEIGHT 1 /* Priorities per nice level. */ 75 76 /* 77 * The schedulable entity that can be given a context to run. 78 * A process may have several of these. Probably one per processor 79 * but posibly a few more. In this universe they are grouped 80 * with a KSEG that contains the priority and niceness 81 * for the group. 82 */ 83 struct kse { 84 TAILQ_ENTRY(kse) ke_procq; /* (j/z) Run queue. */ 85 struct thread *ke_thread; /* (*) Active associated thread. */ 86 fixpt_t ke_pctcpu; /* (j) %cpu during p_swtime. */ 87 char ke_rqindex; /* (j) Run queue index. */ 88 enum { 89 KES_THREAD = 0x0, /* slaved to thread state */ 90 KES_ONRUNQ 91 } ke_state; /* (j) KSE status. */ 92 int ke_cpticks; /* (j) Ticks of cpu time. */ 93 struct runq *ke_runq; /* runq the kse is currently on */ 94 }; 95 96 #define ke_proc ke_thread->td_proc 97 #define ke_ksegrp ke_thread->td_ksegrp 98 99 #define td_kse td_sched 100 101 /* flags kept in td_flags */ 102 #define TDF_DIDRUN TDF_SCHED0 /* KSE actually ran. */ 103 #define TDF_EXIT TDF_SCHED1 /* KSE is being killed. */ 104 #define TDF_BOUND TDF_SCHED2 105 106 #define ke_flags ke_thread->td_flags 107 #define KEF_DIDRUN TDF_DIDRUN /* KSE actually ran. */ 108 #define KEF_EXIT TDF_EXIT /* KSE is being killed. */ 109 #define KEF_BOUND TDF_BOUND /* stuck to one CPU */ 110 111 #define SKE_RUNQ_PCPU(ke) \ 112 ((ke)->ke_runq != 0 && (ke)->ke_runq != &runq) 113 114 struct kg_sched { 115 struct thread *skg_last_assigned; /* (j) Last thread assigned to */ 116 /* the system scheduler. */ 117 int skg_avail_opennings; /* (j) Num KSEs requested in group. */ 118 int skg_concurrency; /* (j) Num KSEs requested in group. */ 119 }; 120 #define kg_last_assigned kg_sched->skg_last_assigned 121 #define kg_avail_opennings kg_sched->skg_avail_opennings 122 #define kg_concurrency kg_sched->skg_concurrency 123 124 #define SLOT_RELEASE(kg) \ 125 do { \ 126 kg->kg_avail_opennings++; \ 127 CTR3(KTR_RUNQ, "kg %p(%d) Slot released (->%d)", \ 128 kg, \ 129 kg->kg_concurrency, \ 130 kg->kg_avail_opennings); \ 131 /* KASSERT((kg->kg_avail_opennings <= kg->kg_concurrency), \ 132 ("slots out of whack"));*/ \ 133 } while (0) 134 135 #define SLOT_USE(kg) \ 136 do { \ 137 kg->kg_avail_opennings--; \ 138 CTR3(KTR_RUNQ, "kg %p(%d) Slot used (->%d)", \ 139 kg, \ 140 kg->kg_concurrency, \ 141 kg->kg_avail_opennings); \ 142 /* KASSERT((kg->kg_avail_opennings >= 0), \ 143 ("slots out of whack"));*/ \ 144 } while (0) 145 146 /* 147 * KSE_CAN_MIGRATE macro returns true if the kse can migrate between 148 * cpus. 149 */ 150 #define KSE_CAN_MIGRATE(ke) \ 151 ((ke)->ke_thread->td_pinned == 0 && ((ke)->ke_flags & KEF_BOUND) == 0) 152 153 static struct kse kse0; 154 static struct kg_sched kg_sched0; 155 156 static int sched_tdcnt; /* Total runnable threads in the system. */ 157 static int sched_quantum; /* Roundrobin scheduling quantum in ticks. */ 158 #define SCHED_QUANTUM (hz / 10) /* Default sched quantum */ 159 160 static void slot_fill(struct ksegrp *kg); 161 static struct kse *sched_choose(void); /* XXX Should be thread * */ 162 163 static void setup_runqs(void); 164 static void schedcpu(void); 165 static void schedcpu_thread(void); 166 static void sched_priority(struct thread *td, u_char prio); 167 static void sched_setup(void *dummy); 168 static void maybe_resched(struct thread *td); 169 static void updatepri(struct ksegrp *kg); 170 static void resetpriority(struct ksegrp *kg); 171 static void resetpriority_thread(struct thread *td, struct ksegrp *kg); 172 #ifdef SMP 173 static int forward_wakeup(int cpunum); 174 #endif 175 176 static struct kproc_desc sched_kp = { 177 "schedcpu", 178 schedcpu_thread, 179 NULL 180 }; 181 SYSINIT(schedcpu, SI_SUB_RUN_SCHEDULER, SI_ORDER_FIRST, kproc_start, &sched_kp) 182 SYSINIT(sched_setup, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, sched_setup, NULL) 183 184 /* 185 * Global run queue. 186 */ 187 static struct runq runq; 188 189 #ifdef SMP 190 /* 191 * Per-CPU run queues 192 */ 193 static struct runq runq_pcpu[MAXCPU]; 194 #endif 195 196 static void 197 setup_runqs(void) 198 { 199 #ifdef SMP 200 int i; 201 202 for (i = 0; i < MAXCPU; ++i) 203 runq_init(&runq_pcpu[i]); 204 #endif 205 206 runq_init(&runq); 207 } 208 209 static int 210 sysctl_kern_quantum(SYSCTL_HANDLER_ARGS) 211 { 212 int error, new_val; 213 214 new_val = sched_quantum * tick; 215 error = sysctl_handle_int(oidp, &new_val, 0, req); 216 if (error != 0 || req->newptr == NULL) 217 return (error); 218 if (new_val < tick) 219 return (EINVAL); 220 sched_quantum = new_val / tick; 221 hogticks = 2 * sched_quantum; 222 return (0); 223 } 224 225 SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RD, 0, "Scheduler"); 226 227 SYSCTL_STRING(_kern_sched, OID_AUTO, name, CTLFLAG_RD, "4BSD", 0, 228 "Scheduler name"); 229 230 SYSCTL_PROC(_kern_sched, OID_AUTO, quantum, CTLTYPE_INT | CTLFLAG_RW, 231 0, sizeof sched_quantum, sysctl_kern_quantum, "I", 232 "Roundrobin scheduling quantum in microseconds"); 233 234 #ifdef SMP 235 /* Enable forwarding of wakeups to all other cpus */ 236 SYSCTL_NODE(_kern_sched, OID_AUTO, ipiwakeup, CTLFLAG_RD, NULL, "Kernel SMP"); 237 238 static int forward_wakeup_enabled = 1; 239 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, enabled, CTLFLAG_RW, 240 &forward_wakeup_enabled, 0, 241 "Forwarding of wakeup to idle CPUs"); 242 243 static int forward_wakeups_requested = 0; 244 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, requested, CTLFLAG_RD, 245 &forward_wakeups_requested, 0, 246 "Requests for Forwarding of wakeup to idle CPUs"); 247 248 static int forward_wakeups_delivered = 0; 249 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, delivered, CTLFLAG_RD, 250 &forward_wakeups_delivered, 0, 251 "Completed Forwarding of wakeup to idle CPUs"); 252 253 static int forward_wakeup_use_mask = 1; 254 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, usemask, CTLFLAG_RW, 255 &forward_wakeup_use_mask, 0, 256 "Use the mask of idle cpus"); 257 258 static int forward_wakeup_use_loop = 0; 259 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, useloop, CTLFLAG_RW, 260 &forward_wakeup_use_loop, 0, 261 "Use a loop to find idle cpus"); 262 263 static int forward_wakeup_use_single = 0; 264 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, onecpu, CTLFLAG_RW, 265 &forward_wakeup_use_single, 0, 266 "Only signal one idle cpu"); 267 268 static int forward_wakeup_use_htt = 0; 269 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, htt2, CTLFLAG_RW, 270 &forward_wakeup_use_htt, 0, 271 "account for htt"); 272 273 #endif 274 static int sched_followon = 0; 275 SYSCTL_INT(_kern_sched, OID_AUTO, followon, CTLFLAG_RW, 276 &sched_followon, 0, 277 "allow threads to share a quantum"); 278 279 static int sched_pfollowons = 0; 280 SYSCTL_INT(_kern_sched, OID_AUTO, pfollowons, CTLFLAG_RD, 281 &sched_pfollowons, 0, 282 "number of followons done to a different ksegrp"); 283 284 static int sched_kgfollowons = 0; 285 SYSCTL_INT(_kern_sched, OID_AUTO, kgfollowons, CTLFLAG_RD, 286 &sched_kgfollowons, 0, 287 "number of followons done in a ksegrp"); 288 289 static __inline void 290 sched_load_add(void) 291 { 292 sched_tdcnt++; 293 CTR1(KTR_SCHED, "global load: %d", sched_tdcnt); 294 } 295 296 static __inline void 297 sched_load_rem(void) 298 { 299 sched_tdcnt--; 300 CTR1(KTR_SCHED, "global load: %d", sched_tdcnt); 301 } 302 /* 303 * Arrange to reschedule if necessary, taking the priorities and 304 * schedulers into account. 305 */ 306 static void 307 maybe_resched(struct thread *td) 308 { 309 310 mtx_assert(&sched_lock, MA_OWNED); 311 if (td->td_priority < curthread->td_priority) 312 curthread->td_flags |= TDF_NEEDRESCHED; 313 } 314 315 /* 316 * Constants for digital decay and forget: 317 * 90% of (kg_estcpu) usage in 5 * loadav time 318 * 95% of (ke_pctcpu) usage in 60 seconds (load insensitive) 319 * Note that, as ps(1) mentions, this can let percentages 320 * total over 100% (I've seen 137.9% for 3 processes). 321 * 322 * Note that schedclock() updates kg_estcpu and p_cpticks asynchronously. 323 * 324 * We wish to decay away 90% of kg_estcpu in (5 * loadavg) seconds. 325 * That is, the system wants to compute a value of decay such 326 * that the following for loop: 327 * for (i = 0; i < (5 * loadavg); i++) 328 * kg_estcpu *= decay; 329 * will compute 330 * kg_estcpu *= 0.1; 331 * for all values of loadavg: 332 * 333 * Mathematically this loop can be expressed by saying: 334 * decay ** (5 * loadavg) ~= .1 335 * 336 * The system computes decay as: 337 * decay = (2 * loadavg) / (2 * loadavg + 1) 338 * 339 * We wish to prove that the system's computation of decay 340 * will always fulfill the equation: 341 * decay ** (5 * loadavg) ~= .1 342 * 343 * If we compute b as: 344 * b = 2 * loadavg 345 * then 346 * decay = b / (b + 1) 347 * 348 * We now need to prove two things: 349 * 1) Given factor ** (5 * loadavg) ~= .1, prove factor == b/(b+1) 350 * 2) Given b/(b+1) ** power ~= .1, prove power == (5 * loadavg) 351 * 352 * Facts: 353 * For x close to zero, exp(x) =~ 1 + x, since 354 * exp(x) = 0! + x**1/1! + x**2/2! + ... . 355 * therefore exp(-1/b) =~ 1 - (1/b) = (b-1)/b. 356 * For x close to zero, ln(1+x) =~ x, since 357 * ln(1+x) = x - x**2/2 + x**3/3 - ... -1 < x < 1 358 * therefore ln(b/(b+1)) = ln(1 - 1/(b+1)) =~ -1/(b+1). 359 * ln(.1) =~ -2.30 360 * 361 * Proof of (1): 362 * Solve (factor)**(power) =~ .1 given power (5*loadav): 363 * solving for factor, 364 * ln(factor) =~ (-2.30/5*loadav), or 365 * factor =~ exp(-1/((5/2.30)*loadav)) =~ exp(-1/(2*loadav)) = 366 * exp(-1/b) =~ (b-1)/b =~ b/(b+1). QED 367 * 368 * Proof of (2): 369 * Solve (factor)**(power) =~ .1 given factor == (b/(b+1)): 370 * solving for power, 371 * power*ln(b/(b+1)) =~ -2.30, or 372 * power =~ 2.3 * (b + 1) = 4.6*loadav + 2.3 =~ 5*loadav. QED 373 * 374 * Actual power values for the implemented algorithm are as follows: 375 * loadav: 1 2 3 4 376 * power: 5.68 10.32 14.94 19.55 377 */ 378 379 /* calculations for digital decay to forget 90% of usage in 5*loadav sec */ 380 #define loadfactor(loadav) (2 * (loadav)) 381 #define decay_cpu(loadfac, cpu) (((loadfac) * (cpu)) / ((loadfac) + FSCALE)) 382 383 /* decay 95% of `ke_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */ 384 static fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */ 385 SYSCTL_INT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, ""); 386 387 /* 388 * If `ccpu' is not equal to `exp(-1/20)' and you still want to use the 389 * faster/more-accurate formula, you'll have to estimate CCPU_SHIFT below 390 * and possibly adjust FSHIFT in "param.h" so that (FSHIFT >= CCPU_SHIFT). 391 * 392 * To estimate CCPU_SHIFT for exp(-1/20), the following formula was used: 393 * 1 - exp(-1/20) ~= 0.0487 ~= 0.0488 == 1 (fixed pt, *11* bits). 394 * 395 * If you don't want to bother with the faster/more-accurate formula, you 396 * can set CCPU_SHIFT to (FSHIFT + 1) which will use a slower/less-accurate 397 * (more general) method of calculating the %age of CPU used by a process. 398 */ 399 #define CCPU_SHIFT 11 400 401 /* 402 * Recompute process priorities, every hz ticks. 403 * MP-safe, called without the Giant mutex. 404 */ 405 /* ARGSUSED */ 406 static void 407 schedcpu(void) 408 { 409 register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]); 410 struct thread *td; 411 struct proc *p; 412 struct kse *ke; 413 struct ksegrp *kg; 414 int awake, realstathz; 415 416 realstathz = stathz ? stathz : hz; 417 sx_slock(&allproc_lock); 418 FOREACH_PROC_IN_SYSTEM(p) { 419 /* 420 * Prevent state changes and protect run queue. 421 */ 422 mtx_lock_spin(&sched_lock); 423 /* 424 * Increment time in/out of memory. We ignore overflow; with 425 * 16-bit int's (remember them?) overflow takes 45 days. 426 */ 427 p->p_swtime++; 428 FOREACH_KSEGRP_IN_PROC(p, kg) { 429 awake = 0; 430 FOREACH_THREAD_IN_GROUP(kg, td) { 431 ke = td->td_kse; 432 /* 433 * Increment sleep time (if sleeping). We 434 * ignore overflow, as above. 435 */ 436 /* 437 * The kse slptimes are not touched in wakeup 438 * because the thread may not HAVE a KSE. 439 */ 440 if (ke->ke_state == KES_ONRUNQ) { 441 awake = 1; 442 ke->ke_flags &= ~KEF_DIDRUN; 443 } else if ((ke->ke_state == KES_THREAD) && 444 (TD_IS_RUNNING(td))) { 445 awake = 1; 446 /* Do not clear KEF_DIDRUN */ 447 } else if (ke->ke_flags & KEF_DIDRUN) { 448 awake = 1; 449 ke->ke_flags &= ~KEF_DIDRUN; 450 } 451 452 /* 453 * ke_pctcpu is only for ps and ttyinfo(). 454 * Do it per kse, and add them up at the end? 455 * XXXKSE 456 */ 457 ke->ke_pctcpu = (ke->ke_pctcpu * ccpu) >> 458 FSHIFT; 459 /* 460 * If the kse has been idle the entire second, 461 * stop recalculating its priority until 462 * it wakes up. 463 */ 464 if (ke->ke_cpticks == 0) 465 continue; 466 #if (FSHIFT >= CCPU_SHIFT) 467 ke->ke_pctcpu += (realstathz == 100) 468 ? ((fixpt_t) ke->ke_cpticks) << 469 (FSHIFT - CCPU_SHIFT) : 470 100 * (((fixpt_t) ke->ke_cpticks) 471 << (FSHIFT - CCPU_SHIFT)) / realstathz; 472 #else 473 ke->ke_pctcpu += ((FSCALE - ccpu) * 474 (ke->ke_cpticks * 475 FSCALE / realstathz)) >> FSHIFT; 476 #endif 477 ke->ke_cpticks = 0; 478 } /* end of kse loop */ 479 /* 480 * If there are ANY running threads in this KSEGRP, 481 * then don't count it as sleeping. 482 */ 483 if (awake) { 484 if (kg->kg_slptime > 1) { 485 /* 486 * In an ideal world, this should not 487 * happen, because whoever woke us 488 * up from the long sleep should have 489 * unwound the slptime and reset our 490 * priority before we run at the stale 491 * priority. Should KASSERT at some 492 * point when all the cases are fixed. 493 */ 494 updatepri(kg); 495 } 496 kg->kg_slptime = 0; 497 } else 498 kg->kg_slptime++; 499 if (kg->kg_slptime > 1) 500 continue; 501 kg->kg_estcpu = decay_cpu(loadfac, kg->kg_estcpu); 502 resetpriority(kg); 503 FOREACH_THREAD_IN_GROUP(kg, td) { 504 resetpriority_thread(td, kg); 505 } 506 } /* end of ksegrp loop */ 507 mtx_unlock_spin(&sched_lock); 508 } /* end of process loop */ 509 sx_sunlock(&allproc_lock); 510 } 511 512 /* 513 * Main loop for a kthread that executes schedcpu once a second. 514 */ 515 static void 516 schedcpu_thread(void) 517 { 518 int nowake; 519 520 for (;;) { 521 schedcpu(); 522 tsleep(&nowake, 0, "-", hz); 523 } 524 } 525 526 /* 527 * Recalculate the priority of a process after it has slept for a while. 528 * For all load averages >= 1 and max kg_estcpu of 255, sleeping for at 529 * least six times the loadfactor will decay kg_estcpu to zero. 530 */ 531 static void 532 updatepri(struct ksegrp *kg) 533 { 534 register fixpt_t loadfac; 535 register unsigned int newcpu; 536 537 loadfac = loadfactor(averunnable.ldavg[0]); 538 if (kg->kg_slptime > 5 * loadfac) 539 kg->kg_estcpu = 0; 540 else { 541 newcpu = kg->kg_estcpu; 542 kg->kg_slptime--; /* was incremented in schedcpu() */ 543 while (newcpu && --kg->kg_slptime) 544 newcpu = decay_cpu(loadfac, newcpu); 545 kg->kg_estcpu = newcpu; 546 } 547 } 548 549 /* 550 * Compute the priority of a process when running in user mode. 551 * Arrange to reschedule if the resulting priority is better 552 * than that of the current process. 553 */ 554 static void 555 resetpriority(struct ksegrp *kg) 556 { 557 register unsigned int newpriority; 558 559 if (kg->kg_pri_class == PRI_TIMESHARE) { 560 newpriority = PUSER + kg->kg_estcpu / INVERSE_ESTCPU_WEIGHT + 561 NICE_WEIGHT * (kg->kg_proc->p_nice - PRIO_MIN); 562 newpriority = min(max(newpriority, PRI_MIN_TIMESHARE), 563 PRI_MAX_TIMESHARE); 564 kg->kg_user_pri = newpriority; 565 } 566 } 567 568 /* 569 * Update the thread's priority when the associated ksegroup's user 570 * priority changes. 571 */ 572 static void 573 resetpriority_thread(struct thread *td, struct ksegrp *kg) 574 { 575 576 /* Only change threads with a time sharing user priority. */ 577 if (td->td_priority < PRI_MIN_TIMESHARE || 578 td->td_priority > PRI_MAX_TIMESHARE) 579 return; 580 581 /* XXX the whole needresched thing is broken, but not silly. */ 582 maybe_resched(td); 583 584 sched_prio(td, kg->kg_user_pri); 585 } 586 587 /* ARGSUSED */ 588 static void 589 sched_setup(void *dummy) 590 { 591 setup_runqs(); 592 593 if (sched_quantum == 0) 594 sched_quantum = SCHED_QUANTUM; 595 hogticks = 2 * sched_quantum; 596 597 /* Account for thread0. */ 598 sched_load_add(); 599 } 600 601 /* External interfaces start here */ 602 /* 603 * Very early in the boot some setup of scheduler-specific 604 * parts of proc0 and of some scheduler resources needs to be done. 605 * Called from: 606 * proc0_init() 607 */ 608 void 609 schedinit(void) 610 { 611 /* 612 * Set up the scheduler specific parts of proc0. 613 */ 614 proc0.p_sched = NULL; /* XXX */ 615 ksegrp0.kg_sched = &kg_sched0; 616 thread0.td_sched = &kse0; 617 kse0.ke_thread = &thread0; 618 kse0.ke_state = KES_THREAD; 619 kg_sched0.skg_concurrency = 1; 620 kg_sched0.skg_avail_opennings = 0; /* we are already running */ 621 } 622 623 int 624 sched_runnable(void) 625 { 626 #ifdef SMP 627 return runq_check(&runq) + runq_check(&runq_pcpu[PCPU_GET(cpuid)]); 628 #else 629 return runq_check(&runq); 630 #endif 631 } 632 633 int 634 sched_rr_interval(void) 635 { 636 if (sched_quantum == 0) 637 sched_quantum = SCHED_QUANTUM; 638 return (sched_quantum); 639 } 640 641 /* 642 * We adjust the priority of the current process. The priority of 643 * a process gets worse as it accumulates CPU time. The cpu usage 644 * estimator (kg_estcpu) is increased here. resetpriority() will 645 * compute a different priority each time kg_estcpu increases by 646 * INVERSE_ESTCPU_WEIGHT 647 * (until MAXPRI is reached). The cpu usage estimator ramps up 648 * quite quickly when the process is running (linearly), and decays 649 * away exponentially, at a rate which is proportionally slower when 650 * the system is busy. The basic principle is that the system will 651 * 90% forget that the process used a lot of CPU time in 5 * loadav 652 * seconds. This causes the system to favor processes which haven't 653 * run much recently, and to round-robin among other processes. 654 */ 655 void 656 sched_clock(struct thread *td) 657 { 658 struct ksegrp *kg; 659 struct kse *ke; 660 661 mtx_assert(&sched_lock, MA_OWNED); 662 kg = td->td_ksegrp; 663 ke = td->td_kse; 664 665 ke->ke_cpticks++; 666 kg->kg_estcpu = ESTCPULIM(kg->kg_estcpu + 1); 667 if ((kg->kg_estcpu % INVERSE_ESTCPU_WEIGHT) == 0) { 668 resetpriority(kg); 669 resetpriority_thread(td, kg); 670 } 671 672 /* 673 * Force a context switch if the current thread has used up a full 674 * quantum (default quantum is 100ms). 675 */ 676 if (td != PCPU_GET(idlethread) && 677 ticks - PCPU_GET(switchticks) >= sched_quantum) 678 td->td_flags |= TDF_NEEDRESCHED; 679 } 680 681 /* 682 * charge childs scheduling cpu usage to parent. 683 * 684 * XXXKSE assume only one thread & kse & ksegrp keep estcpu in each ksegrp. 685 * Charge it to the ksegrp that did the wait since process estcpu is sum of 686 * all ksegrps, this is strictly as expected. Assume that the child process 687 * aggregated all the estcpu into the 'built-in' ksegrp. 688 */ 689 void 690 sched_exit(struct proc *p, struct thread *td) 691 { 692 sched_exit_ksegrp(FIRST_KSEGRP_IN_PROC(p), td); 693 sched_exit_thread(FIRST_THREAD_IN_PROC(p), td); 694 } 695 696 void 697 sched_exit_ksegrp(struct ksegrp *kg, struct thread *childtd) 698 { 699 700 mtx_assert(&sched_lock, MA_OWNED); 701 kg->kg_estcpu = ESTCPULIM(kg->kg_estcpu + childtd->td_ksegrp->kg_estcpu); 702 } 703 704 void 705 sched_exit_thread(struct thread *td, struct thread *child) 706 { 707 CTR3(KTR_SCHED, "sched_exit_thread: %p(%s) prio %d", 708 child, child->td_proc->p_comm, child->td_priority); 709 if ((child->td_proc->p_flag & P_NOLOAD) == 0) 710 sched_load_rem(); 711 } 712 713 void 714 sched_fork(struct thread *td, struct thread *childtd) 715 { 716 sched_fork_ksegrp(td, childtd->td_ksegrp); 717 sched_fork_thread(td, childtd); 718 } 719 720 void 721 sched_fork_ksegrp(struct thread *td, struct ksegrp *child) 722 { 723 mtx_assert(&sched_lock, MA_OWNED); 724 child->kg_estcpu = td->td_ksegrp->kg_estcpu; 725 } 726 727 void 728 sched_fork_thread(struct thread *td, struct thread *childtd) 729 { 730 sched_newthread(childtd); 731 } 732 733 void 734 sched_nice(struct proc *p, int nice) 735 { 736 struct ksegrp *kg; 737 struct thread *td; 738 739 PROC_LOCK_ASSERT(p, MA_OWNED); 740 mtx_assert(&sched_lock, MA_OWNED); 741 p->p_nice = nice; 742 FOREACH_KSEGRP_IN_PROC(p, kg) { 743 resetpriority(kg); 744 FOREACH_THREAD_IN_GROUP(kg, td) { 745 resetpriority_thread(td, kg); 746 } 747 } 748 } 749 750 void 751 sched_class(struct ksegrp *kg, int class) 752 { 753 mtx_assert(&sched_lock, MA_OWNED); 754 kg->kg_pri_class = class; 755 } 756 757 /* 758 * Adjust the priority of a thread. 759 * This may include moving the thread within the KSEGRP, 760 * changing the assignment of a kse to the thread, 761 * and moving a KSE in the system run queue. 762 */ 763 static void 764 sched_priority(struct thread *td, u_char prio) 765 { 766 CTR6(KTR_SCHED, "sched_prio: %p(%s) prio %d newprio %d by %p(%s)", 767 td, td->td_proc->p_comm, td->td_priority, prio, curthread, 768 curthread->td_proc->p_comm); 769 770 mtx_assert(&sched_lock, MA_OWNED); 771 if (td->td_priority == prio) 772 return; 773 if (TD_ON_RUNQ(td)) { 774 adjustrunqueue(td, prio); 775 } else { 776 td->td_priority = prio; 777 } 778 } 779 780 /* 781 * Update a thread's priority when it is lent another thread's 782 * priority. 783 */ 784 void 785 sched_lend_prio(struct thread *td, u_char prio) 786 { 787 788 td->td_flags |= TDF_BORROWING; 789 sched_priority(td, prio); 790 } 791 792 /* 793 * Restore a thread's priority when priority propagation is 794 * over. The prio argument is the minimum priority the thread 795 * needs to have to satisfy other possible priority lending 796 * requests. If the thread's regulary priority is less 797 * important than prio the thread will keep a priority boost 798 * of prio. 799 */ 800 void 801 sched_unlend_prio(struct thread *td, u_char prio) 802 { 803 u_char base_pri; 804 805 if (td->td_base_pri >= PRI_MIN_TIMESHARE && 806 td->td_base_pri <= PRI_MAX_TIMESHARE) 807 base_pri = td->td_ksegrp->kg_user_pri; 808 else 809 base_pri = td->td_base_pri; 810 if (prio >= base_pri) { 811 td->td_flags &= ~TDF_BORROWING; 812 sched_prio(td, base_pri); 813 } else 814 sched_lend_prio(td, prio); 815 } 816 817 void 818 sched_prio(struct thread *td, u_char prio) 819 { 820 u_char oldprio; 821 822 /* First, update the base priority. */ 823 td->td_base_pri = prio; 824 825 /* 826 * If the thread is borrowing another thread's priority, don't ever 827 * lower the priority. 828 */ 829 if (td->td_flags & TDF_BORROWING && td->td_priority < prio) 830 return; 831 832 /* Change the real priority. */ 833 oldprio = td->td_priority; 834 sched_priority(td, prio); 835 836 /* 837 * If the thread is on a turnstile, then let the turnstile update 838 * its state. 839 */ 840 if (TD_ON_LOCK(td) && oldprio != prio) 841 turnstile_adjust(td, oldprio); 842 } 843 844 void 845 sched_sleep(struct thread *td) 846 { 847 848 mtx_assert(&sched_lock, MA_OWNED); 849 td->td_ksegrp->kg_slptime = 0; 850 } 851 852 static void remrunqueue(struct thread *td); 853 854 void 855 sched_switch(struct thread *td, struct thread *newtd, int flags) 856 { 857 struct kse *ke; 858 struct ksegrp *kg; 859 struct proc *p; 860 861 ke = td->td_kse; 862 p = td->td_proc; 863 864 mtx_assert(&sched_lock, MA_OWNED); 865 866 if ((p->p_flag & P_NOLOAD) == 0) 867 sched_load_rem(); 868 /* 869 * We are volunteering to switch out so we get to nominate 870 * a successor for the rest of our quantum 871 * First try another thread in our ksegrp, and then look for 872 * other ksegrps in our process. 873 */ 874 if (sched_followon && 875 (p->p_flag & P_HADTHREADS) && 876 (flags & SW_VOL) && 877 newtd == NULL) { 878 /* lets schedule another thread from this process */ 879 kg = td->td_ksegrp; 880 if ((newtd = TAILQ_FIRST(&kg->kg_runq))) { 881 remrunqueue(newtd); 882 sched_kgfollowons++; 883 } else { 884 FOREACH_KSEGRP_IN_PROC(p, kg) { 885 if ((newtd = TAILQ_FIRST(&kg->kg_runq))) { 886 sched_pfollowons++; 887 remrunqueue(newtd); 888 break; 889 } 890 } 891 } 892 } 893 894 if (newtd) 895 newtd->td_flags |= (td->td_flags & TDF_NEEDRESCHED); 896 897 td->td_lastcpu = td->td_oncpu; 898 td->td_flags &= ~TDF_NEEDRESCHED; 899 td->td_owepreempt = 0; 900 td->td_oncpu = NOCPU; 901 /* 902 * At the last moment, if this thread is still marked RUNNING, 903 * then put it back on the run queue as it has not been suspended 904 * or stopped or any thing else similar. We never put the idle 905 * threads on the run queue, however. 906 */ 907 if (td == PCPU_GET(idlethread)) 908 TD_SET_CAN_RUN(td); 909 else { 910 SLOT_RELEASE(td->td_ksegrp); 911 if (TD_IS_RUNNING(td)) { 912 /* Put us back on the run queue (kse and all). */ 913 setrunqueue(td, (flags & SW_PREEMPT) ? 914 SRQ_OURSELF|SRQ_YIELDING|SRQ_PREEMPTED : 915 SRQ_OURSELF|SRQ_YIELDING); 916 } else if (p->p_flag & P_HADTHREADS) { 917 /* 918 * We will not be on the run queue. So we must be 919 * sleeping or similar. As it's available, 920 * someone else can use the KSE if they need it. 921 * It's NOT available if we are about to need it 922 */ 923 if (newtd == NULL || newtd->td_ksegrp != td->td_ksegrp) 924 slot_fill(td->td_ksegrp); 925 } 926 } 927 if (newtd) { 928 /* 929 * The thread we are about to run needs to be counted 930 * as if it had been added to the run queue and selected. 931 * It came from: 932 * * A preemption 933 * * An upcall 934 * * A followon 935 */ 936 KASSERT((newtd->td_inhibitors == 0), 937 ("trying to run inhibitted thread")); 938 SLOT_USE(newtd->td_ksegrp); 939 newtd->td_kse->ke_flags |= KEF_DIDRUN; 940 TD_SET_RUNNING(newtd); 941 if ((newtd->td_proc->p_flag & P_NOLOAD) == 0) 942 sched_load_add(); 943 } else { 944 newtd = choosethread(); 945 } 946 947 if (td != newtd) { 948 #ifdef HWPMC_HOOKS 949 if (PMC_PROC_IS_USING_PMCS(td->td_proc)) 950 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT); 951 #endif 952 cpu_switch(td, newtd); 953 #ifdef HWPMC_HOOKS 954 if (PMC_PROC_IS_USING_PMCS(td->td_proc)) 955 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_IN); 956 #endif 957 } 958 959 sched_lock.mtx_lock = (uintptr_t)td; 960 td->td_oncpu = PCPU_GET(cpuid); 961 } 962 963 void 964 sched_wakeup(struct thread *td) 965 { 966 struct ksegrp *kg; 967 968 mtx_assert(&sched_lock, MA_OWNED); 969 kg = td->td_ksegrp; 970 if (kg->kg_slptime > 1) { 971 updatepri(kg); 972 resetpriority(kg); 973 } 974 kg->kg_slptime = 0; 975 setrunqueue(td, SRQ_BORING); 976 } 977 978 #ifdef SMP 979 /* enable HTT_2 if you have a 2-way HTT cpu.*/ 980 static int 981 forward_wakeup(int cpunum) 982 { 983 cpumask_t map, me, dontuse; 984 cpumask_t map2; 985 struct pcpu *pc; 986 cpumask_t id, map3; 987 988 mtx_assert(&sched_lock, MA_OWNED); 989 990 CTR0(KTR_RUNQ, "forward_wakeup()"); 991 992 if ((!forward_wakeup_enabled) || 993 (forward_wakeup_use_mask == 0 && forward_wakeup_use_loop == 0)) 994 return (0); 995 if (!smp_started || cold || panicstr) 996 return (0); 997 998 forward_wakeups_requested++; 999 1000 /* 1001 * check the idle mask we received against what we calculated before 1002 * in the old version. 1003 */ 1004 me = PCPU_GET(cpumask); 1005 /* 1006 * don't bother if we should be doing it ourself.. 1007 */ 1008 if ((me & idle_cpus_mask) && (cpunum == NOCPU || me == (1 << cpunum))) 1009 return (0); 1010 1011 dontuse = me | stopped_cpus | hlt_cpus_mask; 1012 map3 = 0; 1013 if (forward_wakeup_use_loop) { 1014 SLIST_FOREACH(pc, &cpuhead, pc_allcpu) { 1015 id = pc->pc_cpumask; 1016 if ( (id & dontuse) == 0 && 1017 pc->pc_curthread == pc->pc_idlethread) { 1018 map3 |= id; 1019 } 1020 } 1021 } 1022 1023 if (forward_wakeup_use_mask) { 1024 map = 0; 1025 map = idle_cpus_mask & ~dontuse; 1026 1027 /* If they are both on, compare and use loop if different */ 1028 if (forward_wakeup_use_loop) { 1029 if (map != map3) { 1030 printf("map (%02X) != map3 (%02X)\n", 1031 map, map3); 1032 map = map3; 1033 } 1034 } 1035 } else { 1036 map = map3; 1037 } 1038 /* If we only allow a specific CPU, then mask off all the others */ 1039 if (cpunum != NOCPU) { 1040 KASSERT((cpunum <= mp_maxcpus),("forward_wakeup: bad cpunum.")); 1041 map &= (1 << cpunum); 1042 } else { 1043 /* Try choose an idle die. */ 1044 if (forward_wakeup_use_htt) { 1045 map2 = (map & (map >> 1)) & 0x5555; 1046 if (map2) { 1047 map = map2; 1048 } 1049 } 1050 1051 /* set only one bit */ 1052 if (forward_wakeup_use_single) { 1053 map = map & ((~map) + 1); 1054 } 1055 } 1056 if (map) { 1057 forward_wakeups_delivered++; 1058 ipi_selected(map, IPI_AST); 1059 return (1); 1060 } 1061 if (cpunum == NOCPU) 1062 printf("forward_wakeup: Idle processor not found\n"); 1063 return (0); 1064 } 1065 #endif 1066 1067 #ifdef SMP 1068 static void kick_other_cpu(int pri,int cpuid); 1069 1070 static void 1071 kick_other_cpu(int pri,int cpuid) 1072 { 1073 struct pcpu * pcpu = pcpu_find(cpuid); 1074 int cpri = pcpu->pc_curthread->td_priority; 1075 1076 if (idle_cpus_mask & pcpu->pc_cpumask) { 1077 forward_wakeups_delivered++; 1078 ipi_selected(pcpu->pc_cpumask, IPI_AST); 1079 return; 1080 } 1081 1082 if (pri >= cpri) 1083 return; 1084 1085 #if defined(IPI_PREEMPTION) && defined(PREEMPTION) 1086 #if !defined(FULL_PREEMPTION) 1087 if (pri <= PRI_MAX_ITHD) 1088 #endif /* ! FULL_PREEMPTION */ 1089 { 1090 ipi_selected(pcpu->pc_cpumask, IPI_PREEMPT); 1091 return; 1092 } 1093 #endif /* defined(IPI_PREEMPTION) && defined(PREEMPTION) */ 1094 1095 pcpu->pc_curthread->td_flags |= TDF_NEEDRESCHED; 1096 ipi_selected( pcpu->pc_cpumask , IPI_AST); 1097 return; 1098 } 1099 #endif /* SMP */ 1100 1101 void 1102 sched_add(struct thread *td, int flags) 1103 #ifdef SMP 1104 { 1105 struct kse *ke; 1106 int forwarded = 0; 1107 int cpu; 1108 int single_cpu = 0; 1109 1110 ke = td->td_kse; 1111 mtx_assert(&sched_lock, MA_OWNED); 1112 KASSERT(ke->ke_state != KES_ONRUNQ, 1113 ("sched_add: kse %p (%s) already in run queue", ke, 1114 ke->ke_proc->p_comm)); 1115 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1116 ("sched_add: process swapped out")); 1117 CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)", 1118 td, td->td_proc->p_comm, td->td_priority, curthread, 1119 curthread->td_proc->p_comm); 1120 1121 1122 if (td->td_pinned != 0) { 1123 cpu = td->td_lastcpu; 1124 ke->ke_runq = &runq_pcpu[cpu]; 1125 single_cpu = 1; 1126 CTR3(KTR_RUNQ, 1127 "sched_add: Put kse:%p(td:%p) on cpu%d runq", ke, td, cpu); 1128 } else if ((ke)->ke_flags & KEF_BOUND) { 1129 /* Find CPU from bound runq */ 1130 KASSERT(SKE_RUNQ_PCPU(ke),("sched_add: bound kse not on cpu runq")); 1131 cpu = ke->ke_runq - &runq_pcpu[0]; 1132 single_cpu = 1; 1133 CTR3(KTR_RUNQ, 1134 "sched_add: Put kse:%p(td:%p) on cpu%d runq", ke, td, cpu); 1135 } else { 1136 CTR2(KTR_RUNQ, 1137 "sched_add: adding kse:%p (td:%p) to gbl runq", ke, td); 1138 cpu = NOCPU; 1139 ke->ke_runq = &runq; 1140 } 1141 1142 if (single_cpu && (cpu != PCPU_GET(cpuid))) { 1143 kick_other_cpu(td->td_priority,cpu); 1144 } else { 1145 1146 if (!single_cpu) { 1147 cpumask_t me = PCPU_GET(cpumask); 1148 int idle = idle_cpus_mask & me; 1149 1150 if (!idle && ((flags & SRQ_INTR) == 0) && 1151 (idle_cpus_mask & ~(hlt_cpus_mask | me))) 1152 forwarded = forward_wakeup(cpu); 1153 } 1154 1155 if (!forwarded) { 1156 if ((flags & SRQ_YIELDING) == 0 && maybe_preempt(td)) 1157 return; 1158 else 1159 maybe_resched(td); 1160 } 1161 } 1162 1163 if ((td->td_proc->p_flag & P_NOLOAD) == 0) 1164 sched_load_add(); 1165 SLOT_USE(td->td_ksegrp); 1166 runq_add(ke->ke_runq, ke, flags); 1167 ke->ke_state = KES_ONRUNQ; 1168 } 1169 #else /* SMP */ 1170 { 1171 struct kse *ke; 1172 ke = td->td_kse; 1173 mtx_assert(&sched_lock, MA_OWNED); 1174 KASSERT(ke->ke_state != KES_ONRUNQ, 1175 ("sched_add: kse %p (%s) already in run queue", ke, 1176 ke->ke_proc->p_comm)); 1177 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1178 ("sched_add: process swapped out")); 1179 CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)", 1180 td, td->td_proc->p_comm, td->td_priority, curthread, 1181 curthread->td_proc->p_comm); 1182 CTR2(KTR_RUNQ, "sched_add: adding kse:%p (td:%p) to runq", ke, td); 1183 ke->ke_runq = &runq; 1184 1185 /* 1186 * If we are yielding (on the way out anyhow) 1187 * or the thread being saved is US, 1188 * then don't try be smart about preemption 1189 * or kicking off another CPU 1190 * as it won't help and may hinder. 1191 * In the YIEDLING case, we are about to run whoever is 1192 * being put in the queue anyhow, and in the 1193 * OURSELF case, we are puting ourself on the run queue 1194 * which also only happens when we are about to yield. 1195 */ 1196 if((flags & SRQ_YIELDING) == 0) { 1197 if (maybe_preempt(td)) 1198 return; 1199 } 1200 if ((td->td_proc->p_flag & P_NOLOAD) == 0) 1201 sched_load_add(); 1202 SLOT_USE(td->td_ksegrp); 1203 runq_add(ke->ke_runq, ke, flags); 1204 ke->ke_state = KES_ONRUNQ; 1205 maybe_resched(td); 1206 } 1207 #endif /* SMP */ 1208 1209 void 1210 sched_rem(struct thread *td) 1211 { 1212 struct kse *ke; 1213 1214 ke = td->td_kse; 1215 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1216 ("sched_rem: process swapped out")); 1217 KASSERT((ke->ke_state == KES_ONRUNQ), 1218 ("sched_rem: KSE not on run queue")); 1219 mtx_assert(&sched_lock, MA_OWNED); 1220 CTR5(KTR_SCHED, "sched_rem: %p(%s) prio %d by %p(%s)", 1221 td, td->td_proc->p_comm, td->td_priority, curthread, 1222 curthread->td_proc->p_comm); 1223 1224 if ((td->td_proc->p_flag & P_NOLOAD) == 0) 1225 sched_load_rem(); 1226 SLOT_RELEASE(td->td_ksegrp); 1227 runq_remove(ke->ke_runq, ke); 1228 1229 ke->ke_state = KES_THREAD; 1230 } 1231 1232 /* 1233 * Select threads to run. 1234 * Notice that the running threads still consume a slot. 1235 */ 1236 struct kse * 1237 sched_choose(void) 1238 { 1239 struct kse *ke; 1240 struct runq *rq; 1241 1242 #ifdef SMP 1243 struct kse *kecpu; 1244 1245 rq = &runq; 1246 ke = runq_choose(&runq); 1247 kecpu = runq_choose(&runq_pcpu[PCPU_GET(cpuid)]); 1248 1249 if (ke == NULL || 1250 (kecpu != NULL && 1251 kecpu->ke_thread->td_priority < ke->ke_thread->td_priority)) { 1252 CTR2(KTR_RUNQ, "choosing kse %p from pcpu runq %d", kecpu, 1253 PCPU_GET(cpuid)); 1254 ke = kecpu; 1255 rq = &runq_pcpu[PCPU_GET(cpuid)]; 1256 } else { 1257 CTR1(KTR_RUNQ, "choosing kse %p from main runq", ke); 1258 } 1259 1260 #else 1261 rq = &runq; 1262 ke = runq_choose(&runq); 1263 #endif 1264 1265 if (ke != NULL) { 1266 runq_remove(rq, ke); 1267 ke->ke_state = KES_THREAD; 1268 1269 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1270 ("sched_choose: process swapped out")); 1271 } 1272 return (ke); 1273 } 1274 1275 void 1276 sched_userret(struct thread *td) 1277 { 1278 struct ksegrp *kg; 1279 /* 1280 * XXX we cheat slightly on the locking here to avoid locking in 1281 * the usual case. Setting td_priority here is essentially an 1282 * incomplete workaround for not setting it properly elsewhere. 1283 * Now that some interrupt handlers are threads, not setting it 1284 * properly elsewhere can clobber it in the window between setting 1285 * it here and returning to user mode, so don't waste time setting 1286 * it perfectly here. 1287 */ 1288 KASSERT((td->td_flags & TDF_BORROWING) == 0, 1289 ("thread with borrowed priority returning to userland")); 1290 kg = td->td_ksegrp; 1291 if (td->td_priority != kg->kg_user_pri) { 1292 mtx_lock_spin(&sched_lock); 1293 td->td_priority = kg->kg_user_pri; 1294 td->td_base_pri = kg->kg_user_pri; 1295 mtx_unlock_spin(&sched_lock); 1296 } 1297 } 1298 1299 void 1300 sched_bind(struct thread *td, int cpu) 1301 { 1302 struct kse *ke; 1303 1304 mtx_assert(&sched_lock, MA_OWNED); 1305 KASSERT(TD_IS_RUNNING(td), 1306 ("sched_bind: cannot bind non-running thread")); 1307 1308 ke = td->td_kse; 1309 1310 ke->ke_flags |= KEF_BOUND; 1311 #ifdef SMP 1312 ke->ke_runq = &runq_pcpu[cpu]; 1313 if (PCPU_GET(cpuid) == cpu) 1314 return; 1315 1316 ke->ke_state = KES_THREAD; 1317 1318 mi_switch(SW_VOL, NULL); 1319 #endif 1320 } 1321 1322 void 1323 sched_unbind(struct thread* td) 1324 { 1325 mtx_assert(&sched_lock, MA_OWNED); 1326 td->td_kse->ke_flags &= ~KEF_BOUND; 1327 } 1328 1329 int 1330 sched_is_bound(struct thread *td) 1331 { 1332 mtx_assert(&sched_lock, MA_OWNED); 1333 return (td->td_kse->ke_flags & KEF_BOUND); 1334 } 1335 1336 int 1337 sched_load(void) 1338 { 1339 return (sched_tdcnt); 1340 } 1341 1342 int 1343 sched_sizeof_ksegrp(void) 1344 { 1345 return (sizeof(struct ksegrp) + sizeof(struct kg_sched)); 1346 } 1347 int 1348 sched_sizeof_proc(void) 1349 { 1350 return (sizeof(struct proc)); 1351 } 1352 int 1353 sched_sizeof_thread(void) 1354 { 1355 return (sizeof(struct thread) + sizeof(struct kse)); 1356 } 1357 1358 fixpt_t 1359 sched_pctcpu(struct thread *td) 1360 { 1361 struct kse *ke; 1362 1363 ke = td->td_kse; 1364 return (ke->ke_pctcpu); 1365 1366 return (0); 1367 } 1368 #define KERN_SWITCH_INCLUDE 1 1369 #include "kern/kern_switch.c"
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