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 <sys/umtx.h> 57 #include <machine/pcb.h> 58 #include <machine/smp.h> 59 60 #ifdef HWPMC_HOOKS 61 #include <sys/pmckern.h> 62 #endif 63 64 /* 65 * INVERSE_ESTCPU_WEIGHT is only suitable for statclock() frequencies in 66 * the range 100-256 Hz (approximately). 67 */ 68 #define ESTCPULIM(e) \ 69 min((e), INVERSE_ESTCPU_WEIGHT * (NICE_WEIGHT * (PRIO_MAX - PRIO_MIN) - \ 70 RQ_PPQ) + INVERSE_ESTCPU_WEIGHT - 1) 71 #ifdef SMP 72 #define INVERSE_ESTCPU_WEIGHT (8 * smp_cpus) 73 #else 74 #define INVERSE_ESTCPU_WEIGHT 8 /* 1 / (priorities per estcpu level). */ 75 #endif 76 #define NICE_WEIGHT 1 /* Priorities per nice level. */ 77 78 /* 79 * The schedulable entity that can be given a context to run. 80 * A process may have several of these. Probably one per processor 81 * but possibly a few more. In this universe they are grouped 82 * with a KSEG that contains the priority and niceness 83 * for the group. 84 */ 85 struct kse { 86 TAILQ_ENTRY(kse) ke_procq; /* (j/z) Run queue. */ 87 struct thread *ke_thread; /* (*) Active associated thread. */ 88 fixpt_t ke_pctcpu; /* (j) %cpu during p_swtime. */ 89 u_char ke_rqindex; /* (j) Run queue index. */ 90 enum { 91 KES_THREAD = 0x0, /* slaved to thread state */ 92 KES_ONRUNQ 93 } ke_state; /* (j) KSE status. */ 94 int ke_cpticks; /* (j) Ticks of cpu time. */ 95 struct runq *ke_runq; /* runq the kse is currently on */ 96 }; 97 98 #define ke_proc ke_thread->td_proc 99 #define ke_ksegrp ke_thread->td_ksegrp 100 101 #define td_kse td_sched 102 103 /* flags kept in td_flags */ 104 #define TDF_DIDRUN TDF_SCHED0 /* KSE actually ran. */ 105 #define TDF_EXIT TDF_SCHED1 /* KSE is being killed. */ 106 #define TDF_BOUND TDF_SCHED2 107 108 #define ke_flags ke_thread->td_flags 109 #define KEF_DIDRUN TDF_DIDRUN /* KSE actually ran. */ 110 #define KEF_EXIT TDF_EXIT /* KSE is being killed. */ 111 #define KEF_BOUND TDF_BOUND /* stuck to one CPU */ 112 113 #define SKE_RUNQ_PCPU(ke) \ 114 ((ke)->ke_runq != 0 && (ke)->ke_runq != &runq) 115 116 struct kg_sched { 117 struct thread *skg_last_assigned; /* (j) Last thread assigned to */ 118 /* the system scheduler. */ 119 int skg_avail_opennings; /* (j) Num KSEs requested in group. */ 120 int skg_concurrency; /* (j) Num KSEs requested in group. */ 121 }; 122 #define kg_last_assigned kg_sched->skg_last_assigned 123 #define kg_avail_opennings kg_sched->skg_avail_opennings 124 #define kg_concurrency kg_sched->skg_concurrency 125 126 #define SLOT_RELEASE(kg) \ 127 do { \ 128 kg->kg_avail_opennings++; \ 129 CTR3(KTR_RUNQ, "kg %p(%d) Slot released (->%d)", \ 130 kg, \ 131 kg->kg_concurrency, \ 132 kg->kg_avail_opennings); \ 133 /* KASSERT((kg->kg_avail_opennings <= kg->kg_concurrency), \ 134 ("slots out of whack"));*/ \ 135 } while (0) 136 137 #define SLOT_USE(kg) \ 138 do { \ 139 kg->kg_avail_opennings--; \ 140 CTR3(KTR_RUNQ, "kg %p(%d) Slot used (->%d)", \ 141 kg, \ 142 kg->kg_concurrency, \ 143 kg->kg_avail_opennings); \ 144 /* KASSERT((kg->kg_avail_opennings >= 0), \ 145 ("slots out of whack"));*/ \ 146 } while (0) 147 148 /* 149 * KSE_CAN_MIGRATE macro returns true if the kse can migrate between 150 * cpus. 151 */ 152 #define KSE_CAN_MIGRATE(ke) \ 153 ((ke)->ke_thread->td_pinned == 0 && ((ke)->ke_flags & KEF_BOUND) == 0) 154 155 static struct kse kse0; 156 static struct kg_sched kg_sched0; 157 158 static int sched_tdcnt; /* Total runnable threads in the system. */ 159 static int sched_quantum; /* Roundrobin scheduling quantum in ticks. */ 160 #define SCHED_QUANTUM (hz / 10) /* Default sched quantum */ 161 162 static struct callout roundrobin_callout; 163 164 static void slot_fill(struct ksegrp *kg); 165 static struct kse *sched_choose(void); /* XXX Should be thread * */ 166 167 static void setup_runqs(void); 168 static void roundrobin(void *arg); 169 static void schedcpu(void); 170 static void schedcpu_thread(void); 171 static void sched_priority(struct thread *td, u_char prio); 172 static void sched_setup(void *dummy); 173 static void maybe_resched(struct thread *td); 174 static void updatepri(struct ksegrp *kg); 175 static void resetpriority(struct ksegrp *kg); 176 static void resetpriority_thread(struct thread *td, struct ksegrp *kg); 177 #ifdef SMP 178 static int forward_wakeup(int cpunum); 179 #endif 180 181 static struct kproc_desc sched_kp = { 182 "schedcpu", 183 schedcpu_thread, 184 NULL 185 }; 186 SYSINIT(schedcpu, SI_SUB_RUN_SCHEDULER, SI_ORDER_FIRST, kproc_start, &sched_kp) 187 SYSINIT(sched_setup, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, sched_setup, NULL) 188 189 /* 190 * Global run queue. 191 */ 192 static struct runq runq; 193 194 #ifdef SMP 195 /* 196 * Per-CPU run queues 197 */ 198 static struct runq runq_pcpu[MAXCPU]; 199 #endif 200 201 static void 202 setup_runqs(void) 203 { 204 #ifdef SMP 205 int i; 206 207 for (i = 0; i < MAXCPU; ++i) 208 runq_init(&runq_pcpu[i]); 209 #endif 210 211 runq_init(&runq); 212 } 213 214 static int 215 sysctl_kern_quantum(SYSCTL_HANDLER_ARGS) 216 { 217 int error, new_val; 218 219 new_val = sched_quantum * tick; 220 error = sysctl_handle_int(oidp, &new_val, 0, req); 221 if (error != 0 || req->newptr == NULL) 222 return (error); 223 if (new_val < tick) 224 return (EINVAL); 225 sched_quantum = new_val / tick; 226 hogticks = 2 * sched_quantum; 227 return (0); 228 } 229 230 SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RD, 0, "Scheduler"); 231 232 SYSCTL_STRING(_kern_sched, OID_AUTO, name, CTLFLAG_RD, "4BSD", 0, 233 "Scheduler name"); 234 235 SYSCTL_PROC(_kern_sched, OID_AUTO, quantum, CTLTYPE_INT | CTLFLAG_RW, 236 0, sizeof sched_quantum, sysctl_kern_quantum, "I", 237 "Roundrobin scheduling quantum in microseconds"); 238 239 #ifdef SMP 240 /* Enable forwarding of wakeups to all other cpus */ 241 SYSCTL_NODE(_kern_sched, OID_AUTO, ipiwakeup, CTLFLAG_RD, NULL, "Kernel SMP"); 242 243 static int forward_wakeup_enabled = 1; 244 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, enabled, CTLFLAG_RW, 245 &forward_wakeup_enabled, 0, 246 "Forwarding of wakeup to idle CPUs"); 247 248 static int forward_wakeups_requested = 0; 249 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, requested, CTLFLAG_RD, 250 &forward_wakeups_requested, 0, 251 "Requests for Forwarding of wakeup to idle CPUs"); 252 253 static int forward_wakeups_delivered = 0; 254 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, delivered, CTLFLAG_RD, 255 &forward_wakeups_delivered, 0, 256 "Completed Forwarding of wakeup to idle CPUs"); 257 258 static int forward_wakeup_use_mask = 1; 259 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, usemask, CTLFLAG_RW, 260 &forward_wakeup_use_mask, 0, 261 "Use the mask of idle cpus"); 262 263 static int forward_wakeup_use_loop = 0; 264 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, useloop, CTLFLAG_RW, 265 &forward_wakeup_use_loop, 0, 266 "Use a loop to find idle cpus"); 267 268 static int forward_wakeup_use_single = 0; 269 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, onecpu, CTLFLAG_RW, 270 &forward_wakeup_use_single, 0, 271 "Only signal one idle cpu"); 272 273 static int forward_wakeup_use_htt = 0; 274 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, htt2, CTLFLAG_RW, 275 &forward_wakeup_use_htt, 0, 276 "account for htt"); 277 278 #endif 279 static int sched_followon = 0; 280 SYSCTL_INT(_kern_sched, OID_AUTO, followon, CTLFLAG_RW, 281 &sched_followon, 0, 282 "allow threads to share a quantum"); 283 284 static int sched_pfollowons = 0; 285 SYSCTL_INT(_kern_sched, OID_AUTO, pfollowons, CTLFLAG_RD, 286 &sched_pfollowons, 0, 287 "number of followons done to a different ksegrp"); 288 289 static int sched_kgfollowons = 0; 290 SYSCTL_INT(_kern_sched, OID_AUTO, kgfollowons, CTLFLAG_RD, 291 &sched_kgfollowons, 0, 292 "number of followons done in a ksegrp"); 293 294 static __inline void 295 sched_load_add(void) 296 { 297 sched_tdcnt++; 298 CTR1(KTR_SCHED, "global load: %d", sched_tdcnt); 299 } 300 301 static __inline void 302 sched_load_rem(void) 303 { 304 sched_tdcnt--; 305 CTR1(KTR_SCHED, "global load: %d", sched_tdcnt); 306 } 307 /* 308 * Arrange to reschedule if necessary, taking the priorities and 309 * schedulers into account. 310 */ 311 static void 312 maybe_resched(struct thread *td) 313 { 314 315 mtx_assert(&sched_lock, MA_OWNED); 316 if (td->td_priority < curthread->td_priority) 317 curthread->td_flags |= TDF_NEEDRESCHED; 318 } 319 320 /* 321 * Force switch among equal priority processes every 100ms. 322 * We don't actually need to force a context switch of the current process. 323 * The act of firing the event triggers a context switch to softclock() and 324 * then switching back out again which is equivalent to a preemption, thus 325 * no further work is needed on the local CPU. 326 */ 327 /* ARGSUSED */ 328 static void 329 roundrobin(void *arg) 330 { 331 332 #ifdef SMP 333 mtx_lock_spin(&sched_lock); 334 forward_roundrobin(); 335 mtx_unlock_spin(&sched_lock); 336 #endif 337 338 callout_reset(&roundrobin_callout, sched_quantum, roundrobin, NULL); 339 } 340 341 /* 342 * Constants for digital decay and forget: 343 * 90% of (kg_estcpu) usage in 5 * loadav time 344 * 95% of (ke_pctcpu) usage in 60 seconds (load insensitive) 345 * Note that, as ps(1) mentions, this can let percentages 346 * total over 100% (I've seen 137.9% for 3 processes). 347 * 348 * Note that schedclock() updates kg_estcpu and p_cpticks asynchronously. 349 * 350 * We wish to decay away 90% of kg_estcpu in (5 * loadavg) seconds. 351 * That is, the system wants to compute a value of decay such 352 * that the following for loop: 353 * for (i = 0; i < (5 * loadavg); i++) 354 * kg_estcpu *= decay; 355 * will compute 356 * kg_estcpu *= 0.1; 357 * for all values of loadavg: 358 * 359 * Mathematically this loop can be expressed by saying: 360 * decay ** (5 * loadavg) ~= .1 361 * 362 * The system computes decay as: 363 * decay = (2 * loadavg) / (2 * loadavg + 1) 364 * 365 * We wish to prove that the system's computation of decay 366 * will always fulfill the equation: 367 * decay ** (5 * loadavg) ~= .1 368 * 369 * If we compute b as: 370 * b = 2 * loadavg 371 * then 372 * decay = b / (b + 1) 373 * 374 * We now need to prove two things: 375 * 1) Given factor ** (5 * loadavg) ~= .1, prove factor == b/(b+1) 376 * 2) Given b/(b+1) ** power ~= .1, prove power == (5 * loadavg) 377 * 378 * Facts: 379 * For x close to zero, exp(x) =~ 1 + x, since 380 * exp(x) = 0! + x**1/1! + x**2/2! + ... . 381 * therefore exp(-1/b) =~ 1 - (1/b) = (b-1)/b. 382 * For x close to zero, ln(1+x) =~ x, since 383 * ln(1+x) = x - x**2/2 + x**3/3 - ... -1 < x < 1 384 * therefore ln(b/(b+1)) = ln(1 - 1/(b+1)) =~ -1/(b+1). 385 * ln(.1) =~ -2.30 386 * 387 * Proof of (1): 388 * Solve (factor)**(power) =~ .1 given power (5*loadav): 389 * solving for factor, 390 * ln(factor) =~ (-2.30/5*loadav), or 391 * factor =~ exp(-1/((5/2.30)*loadav)) =~ exp(-1/(2*loadav)) = 392 * exp(-1/b) =~ (b-1)/b =~ b/(b+1). QED 393 * 394 * Proof of (2): 395 * Solve (factor)**(power) =~ .1 given factor == (b/(b+1)): 396 * solving for power, 397 * power*ln(b/(b+1)) =~ -2.30, or 398 * power =~ 2.3 * (b + 1) = 4.6*loadav + 2.3 =~ 5*loadav. QED 399 * 400 * Actual power values for the implemented algorithm are as follows: 401 * loadav: 1 2 3 4 402 * power: 5.68 10.32 14.94 19.55 403 */ 404 405 /* calculations for digital decay to forget 90% of usage in 5*loadav sec */ 406 #define loadfactor(loadav) (2 * (loadav)) 407 #define decay_cpu(loadfac, cpu) (((loadfac) * (cpu)) / ((loadfac) + FSCALE)) 408 409 /* decay 95% of `ke_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */ 410 static fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */ 411 SYSCTL_INT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, ""); 412 413 /* 414 * If `ccpu' is not equal to `exp(-1/20)' and you still want to use the 415 * faster/more-accurate formula, you'll have to estimate CCPU_SHIFT below 416 * and possibly adjust FSHIFT in "param.h" so that (FSHIFT >= CCPU_SHIFT). 417 * 418 * To estimate CCPU_SHIFT for exp(-1/20), the following formula was used: 419 * 1 - exp(-1/20) ~= 0.0487 ~= 0.0488 == 1 (fixed pt, *11* bits). 420 * 421 * If you don't want to bother with the faster/more-accurate formula, you 422 * can set CCPU_SHIFT to (FSHIFT + 1) which will use a slower/less-accurate 423 * (more general) method of calculating the %age of CPU used by a process. 424 */ 425 #define CCPU_SHIFT 11 426 427 /* 428 * Recompute process priorities, every hz ticks. 429 * MP-safe, called without the Giant mutex. 430 */ 431 /* ARGSUSED */ 432 static void 433 schedcpu(void) 434 { 435 register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]); 436 struct thread *td; 437 struct proc *p; 438 struct kse *ke; 439 struct ksegrp *kg; 440 int awake, realstathz; 441 442 realstathz = stathz ? stathz : hz; 443 sx_slock(&allproc_lock); 444 FOREACH_PROC_IN_SYSTEM(p) { 445 /* 446 * Prevent state changes and protect run queue. 447 */ 448 mtx_lock_spin(&sched_lock); 449 /* 450 * Increment time in/out of memory. We ignore overflow; with 451 * 16-bit int's (remember them?) overflow takes 45 days. 452 */ 453 p->p_swtime++; 454 FOREACH_KSEGRP_IN_PROC(p, kg) { 455 awake = 0; 456 FOREACH_THREAD_IN_GROUP(kg, td) { 457 ke = td->td_kse; 458 /* 459 * Increment sleep time (if sleeping). We 460 * ignore overflow, as above. 461 */ 462 /* 463 * The kse slptimes are not touched in wakeup 464 * because the thread may not HAVE a KSE. 465 */ 466 if (ke->ke_state == KES_ONRUNQ) { 467 awake = 1; 468 ke->ke_flags &= ~KEF_DIDRUN; 469 } else if ((ke->ke_state == KES_THREAD) && 470 (TD_IS_RUNNING(td))) { 471 awake = 1; 472 /* Do not clear KEF_DIDRUN */ 473 } else if (ke->ke_flags & KEF_DIDRUN) { 474 awake = 1; 475 ke->ke_flags &= ~KEF_DIDRUN; 476 } 477 478 /* 479 * ke_pctcpu is only for ps and ttyinfo(). 480 * Do it per kse, and add them up at the end? 481 * XXXKSE 482 */ 483 ke->ke_pctcpu = (ke->ke_pctcpu * ccpu) >> 484 FSHIFT; 485 /* 486 * If the kse has been idle the entire second, 487 * stop recalculating its priority until 488 * it wakes up. 489 */ 490 if (ke->ke_cpticks == 0) 491 continue; 492 #if (FSHIFT >= CCPU_SHIFT) 493 ke->ke_pctcpu += (realstathz == 100) 494 ? ((fixpt_t) ke->ke_cpticks) << 495 (FSHIFT - CCPU_SHIFT) : 496 100 * (((fixpt_t) ke->ke_cpticks) 497 << (FSHIFT - CCPU_SHIFT)) / realstathz; 498 #else 499 ke->ke_pctcpu += ((FSCALE - ccpu) * 500 (ke->ke_cpticks * 501 FSCALE / realstathz)) >> FSHIFT; 502 #endif 503 ke->ke_cpticks = 0; 504 } /* end of kse loop */ 505 /* 506 * If there are ANY running threads in this KSEGRP, 507 * then don't count it as sleeping. 508 */ 509 if (awake) { 510 if (kg->kg_slptime > 1) { 511 /* 512 * In an ideal world, this should not 513 * happen, because whoever woke us 514 * up from the long sleep should have 515 * unwound the slptime and reset our 516 * priority before we run at the stale 517 * priority. Should KASSERT at some 518 * point when all the cases are fixed. 519 */ 520 updatepri(kg); 521 } 522 kg->kg_slptime = 0; 523 } else 524 kg->kg_slptime++; 525 if (kg->kg_slptime > 1) 526 continue; 527 kg->kg_estcpu = decay_cpu(loadfac, kg->kg_estcpu); 528 resetpriority(kg); 529 FOREACH_THREAD_IN_GROUP(kg, td) { 530 resetpriority_thread(td, kg); 531 } 532 } /* end of ksegrp loop */ 533 mtx_unlock_spin(&sched_lock); 534 } /* end of process loop */ 535 sx_sunlock(&allproc_lock); 536 } 537 538 /* 539 * Main loop for a kthread that executes schedcpu once a second. 540 */ 541 static void 542 schedcpu_thread(void) 543 { 544 int nowake; 545 546 for (;;) { 547 schedcpu(); 548 tsleep(&nowake, 0, "-", hz); 549 } 550 } 551 552 /* 553 * Recalculate the priority of a process after it has slept for a while. 554 * For all load averages >= 1 and max kg_estcpu of 255, sleeping for at 555 * least six times the loadfactor will decay kg_estcpu to zero. 556 */ 557 static void 558 updatepri(struct ksegrp *kg) 559 { 560 register fixpt_t loadfac; 561 register unsigned int newcpu; 562 563 loadfac = loadfactor(averunnable.ldavg[0]); 564 if (kg->kg_slptime > 5 * loadfac) 565 kg->kg_estcpu = 0; 566 else { 567 newcpu = kg->kg_estcpu; 568 kg->kg_slptime--; /* was incremented in schedcpu() */ 569 while (newcpu && --kg->kg_slptime) 570 newcpu = decay_cpu(loadfac, newcpu); 571 kg->kg_estcpu = newcpu; 572 } 573 } 574 575 /* 576 * Compute the priority of a process when running in user mode. 577 * Arrange to reschedule if the resulting priority is better 578 * than that of the current process. 579 */ 580 static void 581 resetpriority(struct ksegrp *kg) 582 { 583 register unsigned int newpriority; 584 585 if (kg->kg_pri_class == PRI_TIMESHARE) { 586 newpriority = PUSER + kg->kg_estcpu / INVERSE_ESTCPU_WEIGHT + 587 NICE_WEIGHT * (kg->kg_proc->p_nice - PRIO_MIN); 588 newpriority = min(max(newpriority, PRI_MIN_TIMESHARE), 589 PRI_MAX_TIMESHARE); 590 sched_user_prio(kg, newpriority); 591 } 592 } 593 594 /* 595 * Update the thread's priority when the associated ksegroup's user 596 * priority changes. 597 */ 598 static void 599 resetpriority_thread(struct thread *td, struct ksegrp *kg) 600 { 601 602 /* Only change threads with a time sharing user priority. */ 603 if (td->td_priority < PRI_MIN_TIMESHARE || 604 td->td_priority > PRI_MAX_TIMESHARE) 605 return; 606 607 /* XXX the whole needresched thing is broken, but not silly. */ 608 maybe_resched(td); 609 610 sched_prio(td, kg->kg_user_pri); 611 } 612 613 /* ARGSUSED */ 614 static void 615 sched_setup(void *dummy) 616 { 617 setup_runqs(); 618 619 if (sched_quantum == 0) 620 sched_quantum = SCHED_QUANTUM; 621 hogticks = 2 * sched_quantum; 622 623 callout_init(&roundrobin_callout, CALLOUT_MPSAFE); 624 625 /* Kick off timeout driven events by calling first time. */ 626 roundrobin(NULL); 627 628 /* Account for thread0. */ 629 sched_load_add(); 630 } 631 632 /* External interfaces start here */ 633 /* 634 * Very early in the boot some setup of scheduler-specific 635 * parts of proc0 and of some scheduler resources needs to be done. 636 * Called from: 637 * proc0_init() 638 */ 639 void 640 schedinit(void) 641 { 642 /* 643 * Set up the scheduler specific parts of proc0. 644 */ 645 proc0.p_sched = NULL; /* XXX */ 646 ksegrp0.kg_sched = &kg_sched0; 647 thread0.td_sched = &kse0; 648 kse0.ke_thread = &thread0; 649 kse0.ke_state = KES_THREAD; 650 kg_sched0.skg_concurrency = 1; 651 kg_sched0.skg_avail_opennings = 0; /* we are already running */ 652 } 653 654 int 655 sched_runnable(void) 656 { 657 #ifdef SMP 658 return runq_check(&runq) + runq_check(&runq_pcpu[PCPU_GET(cpuid)]); 659 #else 660 return runq_check(&runq); 661 #endif 662 } 663 664 int 665 sched_rr_interval(void) 666 { 667 if (sched_quantum == 0) 668 sched_quantum = SCHED_QUANTUM; 669 return (sched_quantum); 670 } 671 672 /* 673 * We adjust the priority of the current process. The priority of 674 * a process gets worse as it accumulates CPU time. The cpu usage 675 * estimator (kg_estcpu) is increased here. resetpriority() will 676 * compute a different priority each time kg_estcpu increases by 677 * INVERSE_ESTCPU_WEIGHT 678 * (until MAXPRI is reached). The cpu usage estimator ramps up 679 * quite quickly when the process is running (linearly), and decays 680 * away exponentially, at a rate which is proportionally slower when 681 * the system is busy. The basic principle is that the system will 682 * 90% forget that the process used a lot of CPU time in 5 * loadav 683 * seconds. This causes the system to favor processes which haven't 684 * run much recently, and to round-robin among other processes. 685 */ 686 void 687 sched_clock(struct thread *td) 688 { 689 struct ksegrp *kg; 690 struct kse *ke; 691 692 mtx_assert(&sched_lock, MA_OWNED); 693 kg = td->td_ksegrp; 694 ke = td->td_kse; 695 696 ke->ke_cpticks++; 697 kg->kg_estcpu = ESTCPULIM(kg->kg_estcpu + 1); 698 if ((kg->kg_estcpu % INVERSE_ESTCPU_WEIGHT) == 0) { 699 resetpriority(kg); 700 resetpriority_thread(td, kg); 701 } 702 } 703 704 /* 705 * charge childs scheduling cpu usage to parent. 706 * 707 * XXXKSE assume only one thread & kse & ksegrp keep estcpu in each ksegrp. 708 * Charge it to the ksegrp that did the wait since process estcpu is sum of 709 * all ksegrps, this is strictly as expected. Assume that the child process 710 * aggregated all the estcpu into the 'built-in' ksegrp. 711 */ 712 void 713 sched_exit(struct proc *p, struct thread *td) 714 { 715 sched_exit_ksegrp(FIRST_KSEGRP_IN_PROC(p), td); 716 sched_exit_thread(FIRST_THREAD_IN_PROC(p), td); 717 } 718 719 void 720 sched_exit_ksegrp(struct ksegrp *kg, struct thread *childtd) 721 { 722 723 mtx_assert(&sched_lock, MA_OWNED); 724 kg->kg_estcpu = ESTCPULIM(kg->kg_estcpu + childtd->td_ksegrp->kg_estcpu); 725 } 726 727 void 728 sched_exit_thread(struct thread *td, struct thread *child) 729 { 730 CTR3(KTR_SCHED, "sched_exit_thread: %p(%s) prio %d", 731 child, child->td_proc->p_comm, child->td_priority); 732 if ((child->td_proc->p_flag & P_NOLOAD) == 0) 733 sched_load_rem(); 734 } 735 736 void 737 sched_fork(struct thread *td, struct thread *childtd) 738 { 739 sched_fork_ksegrp(td, childtd->td_ksegrp); 740 sched_fork_thread(td, childtd); 741 } 742 743 void 744 sched_fork_ksegrp(struct thread *td, struct ksegrp *child) 745 { 746 mtx_assert(&sched_lock, MA_OWNED); 747 child->kg_estcpu = td->td_ksegrp->kg_estcpu; 748 } 749 750 void 751 sched_fork_thread(struct thread *td, struct thread *childtd) 752 { 753 sched_newthread(childtd); 754 } 755 756 void 757 sched_nice(struct proc *p, int nice) 758 { 759 struct ksegrp *kg; 760 struct thread *td; 761 762 PROC_LOCK_ASSERT(p, MA_OWNED); 763 mtx_assert(&sched_lock, MA_OWNED); 764 p->p_nice = nice; 765 FOREACH_KSEGRP_IN_PROC(p, kg) { 766 resetpriority(kg); 767 FOREACH_THREAD_IN_GROUP(kg, td) { 768 resetpriority_thread(td, kg); 769 } 770 } 771 } 772 773 void 774 sched_class(struct ksegrp *kg, int class) 775 { 776 mtx_assert(&sched_lock, MA_OWNED); 777 kg->kg_pri_class = class; 778 } 779 780 /* 781 * Adjust the priority of a thread. 782 * This may include moving the thread within the KSEGRP, 783 * changing the assignment of a kse to the thread, 784 * and moving a KSE in the system run queue. 785 */ 786 static void 787 sched_priority(struct thread *td, u_char prio) 788 { 789 CTR6(KTR_SCHED, "sched_prio: %p(%s) prio %d newprio %d by %p(%s)", 790 td, td->td_proc->p_comm, td->td_priority, prio, curthread, 791 curthread->td_proc->p_comm); 792 793 mtx_assert(&sched_lock, MA_OWNED); 794 if (td->td_priority == prio) 795 return; 796 if (TD_ON_RUNQ(td)) { 797 adjustrunqueue(td, prio); 798 } else { 799 td->td_priority = prio; 800 } 801 } 802 803 /* 804 * Update a thread's priority when it is lent another thread's 805 * priority. 806 */ 807 void 808 sched_lend_prio(struct thread *td, u_char prio) 809 { 810 811 td->td_flags |= TDF_BORROWING; 812 sched_priority(td, prio); 813 } 814 815 /* 816 * Restore a thread's priority when priority propagation is 817 * over. The prio argument is the minimum priority the thread 818 * needs to have to satisfy other possible priority lending 819 * requests. If the thread's regulary priority is less 820 * important than prio the thread will keep a priority boost 821 * of prio. 822 */ 823 void 824 sched_unlend_prio(struct thread *td, u_char prio) 825 { 826 u_char base_pri; 827 828 if (td->td_base_pri >= PRI_MIN_TIMESHARE && 829 td->td_base_pri <= PRI_MAX_TIMESHARE) 830 base_pri = td->td_ksegrp->kg_user_pri; 831 else 832 base_pri = td->td_base_pri; 833 if (prio >= base_pri) { 834 td->td_flags &= ~TDF_BORROWING; 835 sched_prio(td, base_pri); 836 } else 837 sched_lend_prio(td, prio); 838 } 839 840 void 841 sched_prio(struct thread *td, u_char prio) 842 { 843 u_char oldprio; 844 845 /* First, update the base priority. */ 846 td->td_base_pri = prio; 847 848 /* 849 * If the thread is borrowing another thread's priority, don't ever 850 * lower the priority. 851 */ 852 if (td->td_flags & TDF_BORROWING && td->td_priority < prio) 853 return; 854 855 /* Change the real priority. */ 856 oldprio = td->td_priority; 857 sched_priority(td, prio); 858 859 /* 860 * If the thread is on a turnstile, then let the turnstile update 861 * its state. 862 */ 863 if (TD_ON_LOCK(td) && oldprio != prio) 864 turnstile_adjust(td, oldprio); 865 } 866 867 void 868 sched_user_prio(struct ksegrp *kg, u_char prio) 869 { 870 struct thread *td; 871 u_char oldprio; 872 873 kg->kg_base_user_pri = prio; 874 875 /* XXXKSE only for 1:1 */ 876 877 td = TAILQ_FIRST(&kg->kg_threads); 878 if (td == NULL) { 879 kg->kg_user_pri = prio; 880 return; 881 } 882 883 if (td->td_flags & TDF_UBORROWING && kg->kg_user_pri <= prio) 884 return; 885 886 oldprio = kg->kg_user_pri; 887 kg->kg_user_pri = prio; 888 889 if (TD_ON_UPILOCK(td) && oldprio != prio) 890 umtx_pi_adjust(td, oldprio); 891 } 892 893 void 894 sched_lend_user_prio(struct thread *td, u_char prio) 895 { 896 u_char oldprio; 897 898 td->td_flags |= TDF_UBORROWING; 899 900 oldprio = td->td_ksegrp->kg_user_pri; 901 td->td_ksegrp->kg_user_pri = prio; 902 903 if (TD_ON_UPILOCK(td) && oldprio != prio) 904 umtx_pi_adjust(td, oldprio); 905 } 906 907 void 908 sched_unlend_user_prio(struct thread *td, u_char prio) 909 { 910 struct ksegrp *kg = td->td_ksegrp; 911 u_char base_pri; 912 913 base_pri = kg->kg_base_user_pri; 914 if (prio >= base_pri) { 915 td->td_flags &= ~TDF_UBORROWING; 916 sched_user_prio(kg, base_pri); 917 } else 918 sched_lend_user_prio(td, prio); 919 } 920 921 void 922 sched_sleep(struct thread *td) 923 { 924 925 mtx_assert(&sched_lock, MA_OWNED); 926 td->td_ksegrp->kg_slptime = 0; 927 } 928 929 static void remrunqueue(struct thread *td); 930 931 void 932 sched_switch(struct thread *td, struct thread *newtd, int flags) 933 { 934 struct kse *ke; 935 struct ksegrp *kg; 936 struct proc *p; 937 938 ke = td->td_kse; 939 p = td->td_proc; 940 941 mtx_assert(&sched_lock, MA_OWNED); 942 943 if ((p->p_flag & P_NOLOAD) == 0) 944 sched_load_rem(); 945 /* 946 * We are volunteering to switch out so we get to nominate 947 * a successor for the rest of our quantum 948 * First try another thread in our ksegrp, and then look for 949 * other ksegrps in our process. 950 */ 951 if (sched_followon && 952 (p->p_flag & P_HADTHREADS) && 953 (flags & SW_VOL) && 954 newtd == NULL) { 955 /* lets schedule another thread from this process */ 956 kg = td->td_ksegrp; 957 if ((newtd = TAILQ_FIRST(&kg->kg_runq))) { 958 remrunqueue(newtd); 959 sched_kgfollowons++; 960 } else { 961 FOREACH_KSEGRP_IN_PROC(p, kg) { 962 if ((newtd = TAILQ_FIRST(&kg->kg_runq))) { 963 sched_pfollowons++; 964 remrunqueue(newtd); 965 break; 966 } 967 } 968 } 969 } 970 971 if (newtd) 972 newtd->td_flags |= (td->td_flags & TDF_NEEDRESCHED); 973 974 td->td_lastcpu = td->td_oncpu; 975 td->td_flags &= ~TDF_NEEDRESCHED; 976 td->td_owepreempt = 0; 977 td->td_oncpu = NOCPU; 978 /* 979 * At the last moment, if this thread is still marked RUNNING, 980 * then put it back on the run queue as it has not been suspended 981 * or stopped or any thing else similar. We never put the idle 982 * threads on the run queue, however. 983 */ 984 if (td == PCPU_GET(idlethread)) 985 TD_SET_CAN_RUN(td); 986 else { 987 SLOT_RELEASE(td->td_ksegrp); 988 if (TD_IS_RUNNING(td)) { 989 /* Put us back on the run queue (kse and all). */ 990 setrunqueue(td, (flags & SW_PREEMPT) ? 991 SRQ_OURSELF|SRQ_YIELDING|SRQ_PREEMPTED : 992 SRQ_OURSELF|SRQ_YIELDING); 993 } else if (p->p_flag & P_HADTHREADS) { 994 /* 995 * We will not be on the run queue. So we must be 996 * sleeping or similar. As it's available, 997 * someone else can use the KSE if they need it. 998 * It's NOT available if we are about to need it 999 */ 1000 if (newtd == NULL || newtd->td_ksegrp != td->td_ksegrp) 1001 slot_fill(td->td_ksegrp); 1002 } 1003 } 1004 if (newtd) { 1005 /* 1006 * The thread we are about to run needs to be counted 1007 * as if it had been added to the run queue and selected. 1008 * It came from: 1009 * * A preemption 1010 * * An upcall 1011 * * A followon 1012 */ 1013 KASSERT((newtd->td_inhibitors == 0), 1014 ("trying to run inhibitted thread")); 1015 SLOT_USE(newtd->td_ksegrp); 1016 newtd->td_kse->ke_flags |= KEF_DIDRUN; 1017 TD_SET_RUNNING(newtd); 1018 if ((newtd->td_proc->p_flag & P_NOLOAD) == 0) 1019 sched_load_add(); 1020 } else { 1021 newtd = choosethread(); 1022 } 1023 1024 if (td != newtd) { 1025 #ifdef HWPMC_HOOKS 1026 if (PMC_PROC_IS_USING_PMCS(td->td_proc)) 1027 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT); 1028 #endif 1029 cpu_switch(td, newtd); 1030 #ifdef HWPMC_HOOKS 1031 if (PMC_PROC_IS_USING_PMCS(td->td_proc)) 1032 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_IN); 1033 #endif 1034 } 1035 1036 sched_lock.mtx_lock = (uintptr_t)td; 1037 td->td_oncpu = PCPU_GET(cpuid); 1038 } 1039 1040 void 1041 sched_wakeup(struct thread *td) 1042 { 1043 struct ksegrp *kg; 1044 1045 mtx_assert(&sched_lock, MA_OWNED); 1046 kg = td->td_ksegrp; 1047 if (kg->kg_slptime > 1) { 1048 updatepri(kg); 1049 resetpriority(kg); 1050 } 1051 kg->kg_slptime = 0; 1052 setrunqueue(td, SRQ_BORING); 1053 } 1054 1055 #ifdef SMP 1056 /* enable HTT_2 if you have a 2-way HTT cpu.*/ 1057 static int 1058 forward_wakeup(int cpunum) 1059 { 1060 cpumask_t map, me, dontuse; 1061 cpumask_t map2; 1062 struct pcpu *pc; 1063 cpumask_t id, map3; 1064 1065 mtx_assert(&sched_lock, MA_OWNED); 1066 1067 CTR0(KTR_RUNQ, "forward_wakeup()"); 1068 1069 if ((!forward_wakeup_enabled) || 1070 (forward_wakeup_use_mask == 0 && forward_wakeup_use_loop == 0)) 1071 return (0); 1072 if (!smp_started || cold || panicstr) 1073 return (0); 1074 1075 forward_wakeups_requested++; 1076 1077 /* 1078 * check the idle mask we received against what we calculated before 1079 * in the old version. 1080 */ 1081 me = PCPU_GET(cpumask); 1082 /* 1083 * don't bother if we should be doing it ourself.. 1084 */ 1085 if ((me & idle_cpus_mask) && (cpunum == NOCPU || me == (1 << cpunum))) 1086 return (0); 1087 1088 dontuse = me | stopped_cpus | hlt_cpus_mask; 1089 map3 = 0; 1090 if (forward_wakeup_use_loop) { 1091 SLIST_FOREACH(pc, &cpuhead, pc_allcpu) { 1092 id = pc->pc_cpumask; 1093 if ( (id & dontuse) == 0 && 1094 pc->pc_curthread == pc->pc_idlethread) { 1095 map3 |= id; 1096 } 1097 } 1098 } 1099 1100 if (forward_wakeup_use_mask) { 1101 map = 0; 1102 map = idle_cpus_mask & ~dontuse; 1103 1104 /* If they are both on, compare and use loop if different */ 1105 if (forward_wakeup_use_loop) { 1106 if (map != map3) { 1107 printf("map (%02X) != map3 (%02X)\n", 1108 map, map3); 1109 map = map3; 1110 } 1111 } 1112 } else { 1113 map = map3; 1114 } 1115 /* If we only allow a specific CPU, then mask off all the others */ 1116 if (cpunum != NOCPU) { 1117 KASSERT((cpunum <= mp_maxcpus),("forward_wakeup: bad cpunum.")); 1118 map &= (1 << cpunum); 1119 } else { 1120 /* Try choose an idle die. */ 1121 if (forward_wakeup_use_htt) { 1122 map2 = (map & (map >> 1)) & 0x5555; 1123 if (map2) { 1124 map = map2; 1125 } 1126 } 1127 1128 /* set only one bit */ 1129 if (forward_wakeup_use_single) { 1130 map = map & ((~map) + 1); 1131 } 1132 } 1133 if (map) { 1134 forward_wakeups_delivered++; 1135 ipi_selected(map, IPI_AST); 1136 return (1); 1137 } 1138 if (cpunum == NOCPU) 1139 printf("forward_wakeup: Idle processor not found\n"); 1140 return (0); 1141 } 1142 #endif 1143 1144 #ifdef SMP 1145 static void kick_other_cpu(int pri,int cpuid); 1146 1147 static void 1148 kick_other_cpu(int pri,int cpuid) 1149 { 1150 struct pcpu * pcpu = pcpu_find(cpuid); 1151 int cpri = pcpu->pc_curthread->td_priority; 1152 1153 if (idle_cpus_mask & pcpu->pc_cpumask) { 1154 forward_wakeups_delivered++; 1155 ipi_selected(pcpu->pc_cpumask, IPI_AST); 1156 return; 1157 } 1158 1159 if (pri >= cpri) 1160 return; 1161 1162 #if defined(IPI_PREEMPTION) && defined(PREEMPTION) 1163 #if !defined(FULL_PREEMPTION) 1164 if (pri <= PRI_MAX_ITHD) 1165 #endif /* ! FULL_PREEMPTION */ 1166 { 1167 ipi_selected(pcpu->pc_cpumask, IPI_PREEMPT); 1168 return; 1169 } 1170 #endif /* defined(IPI_PREEMPTION) && defined(PREEMPTION) */ 1171 1172 pcpu->pc_curthread->td_flags |= TDF_NEEDRESCHED; 1173 ipi_selected( pcpu->pc_cpumask , IPI_AST); 1174 return; 1175 } 1176 #endif /* SMP */ 1177 1178 void 1179 sched_add(struct thread *td, int flags) 1180 #ifdef SMP 1181 { 1182 struct kse *ke; 1183 int forwarded = 0; 1184 int cpu; 1185 int single_cpu = 0; 1186 1187 ke = td->td_kse; 1188 mtx_assert(&sched_lock, MA_OWNED); 1189 KASSERT(ke->ke_state != KES_ONRUNQ, 1190 ("sched_add: kse %p (%s) already in run queue", ke, 1191 ke->ke_proc->p_comm)); 1192 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1193 ("sched_add: process swapped out")); 1194 CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)", 1195 td, td->td_proc->p_comm, td->td_priority, curthread, 1196 curthread->td_proc->p_comm); 1197 1198 1199 if (td->td_pinned != 0) { 1200 cpu = td->td_lastcpu; 1201 ke->ke_runq = &runq_pcpu[cpu]; 1202 single_cpu = 1; 1203 CTR3(KTR_RUNQ, 1204 "sched_add: Put kse:%p(td:%p) on cpu%d runq", ke, td, cpu); 1205 } else if ((ke)->ke_flags & KEF_BOUND) { 1206 /* Find CPU from bound runq */ 1207 KASSERT(SKE_RUNQ_PCPU(ke),("sched_add: bound kse not on cpu runq")); 1208 cpu = ke->ke_runq - &runq_pcpu[0]; 1209 single_cpu = 1; 1210 CTR3(KTR_RUNQ, 1211 "sched_add: Put kse:%p(td:%p) on cpu%d runq", ke, td, cpu); 1212 } else { 1213 CTR2(KTR_RUNQ, 1214 "sched_add: adding kse:%p (td:%p) to gbl runq", ke, td); 1215 cpu = NOCPU; 1216 ke->ke_runq = &runq; 1217 } 1218 1219 if (single_cpu && (cpu != PCPU_GET(cpuid))) { 1220 kick_other_cpu(td->td_priority,cpu); 1221 } else { 1222 1223 if (!single_cpu) { 1224 cpumask_t me = PCPU_GET(cpumask); 1225 int idle = idle_cpus_mask & me; 1226 1227 if (!idle && ((flags & SRQ_INTR) == 0) && 1228 (idle_cpus_mask & ~(hlt_cpus_mask | me))) 1229 forwarded = forward_wakeup(cpu); 1230 } 1231 1232 if (!forwarded) { 1233 if ((flags & SRQ_YIELDING) == 0 && maybe_preempt(td)) 1234 return; 1235 else 1236 maybe_resched(td); 1237 } 1238 } 1239 1240 if ((td->td_proc->p_flag & P_NOLOAD) == 0) 1241 sched_load_add(); 1242 SLOT_USE(td->td_ksegrp); 1243 runq_add(ke->ke_runq, ke, flags); 1244 ke->ke_state = KES_ONRUNQ; 1245 } 1246 #else /* SMP */ 1247 { 1248 struct kse *ke; 1249 ke = td->td_kse; 1250 mtx_assert(&sched_lock, MA_OWNED); 1251 KASSERT(ke->ke_state != KES_ONRUNQ, 1252 ("sched_add: kse %p (%s) already in run queue", ke, 1253 ke->ke_proc->p_comm)); 1254 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1255 ("sched_add: process swapped out")); 1256 CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)", 1257 td, td->td_proc->p_comm, td->td_priority, curthread, 1258 curthread->td_proc->p_comm); 1259 CTR2(KTR_RUNQ, "sched_add: adding kse:%p (td:%p) to runq", ke, td); 1260 ke->ke_runq = &runq; 1261 1262 /* 1263 * If we are yielding (on the way out anyhow) 1264 * or the thread being saved is US, 1265 * then don't try be smart about preemption 1266 * or kicking off another CPU 1267 * as it won't help and may hinder. 1268 * In the YIEDLING case, we are about to run whoever is 1269 * being put in the queue anyhow, and in the 1270 * OURSELF case, we are puting ourself on the run queue 1271 * which also only happens when we are about to yield. 1272 */ 1273 if((flags & SRQ_YIELDING) == 0) { 1274 if (maybe_preempt(td)) 1275 return; 1276 } 1277 if ((td->td_proc->p_flag & P_NOLOAD) == 0) 1278 sched_load_add(); 1279 SLOT_USE(td->td_ksegrp); 1280 runq_add(ke->ke_runq, ke, flags); 1281 ke->ke_state = KES_ONRUNQ; 1282 maybe_resched(td); 1283 } 1284 #endif /* SMP */ 1285 1286 void 1287 sched_rem(struct thread *td) 1288 { 1289 struct kse *ke; 1290 1291 ke = td->td_kse; 1292 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1293 ("sched_rem: process swapped out")); 1294 KASSERT((ke->ke_state == KES_ONRUNQ), 1295 ("sched_rem: KSE not on run queue")); 1296 mtx_assert(&sched_lock, MA_OWNED); 1297 CTR5(KTR_SCHED, "sched_rem: %p(%s) prio %d by %p(%s)", 1298 td, td->td_proc->p_comm, td->td_priority, curthread, 1299 curthread->td_proc->p_comm); 1300 1301 if ((td->td_proc->p_flag & P_NOLOAD) == 0) 1302 sched_load_rem(); 1303 SLOT_RELEASE(td->td_ksegrp); 1304 runq_remove(ke->ke_runq, ke); 1305 1306 ke->ke_state = KES_THREAD; 1307 } 1308 1309 /* 1310 * Select threads to run. 1311 * Notice that the running threads still consume a slot. 1312 */ 1313 struct kse * 1314 sched_choose(void) 1315 { 1316 struct kse *ke; 1317 struct runq *rq; 1318 1319 #ifdef SMP 1320 struct kse *kecpu; 1321 1322 rq = &runq; 1323 ke = runq_choose(&runq); 1324 kecpu = runq_choose(&runq_pcpu[PCPU_GET(cpuid)]); 1325 1326 if (ke == NULL || 1327 (kecpu != NULL && 1328 kecpu->ke_thread->td_priority < ke->ke_thread->td_priority)) { 1329 CTR2(KTR_RUNQ, "choosing kse %p from pcpu runq %d", kecpu, 1330 PCPU_GET(cpuid)); 1331 ke = kecpu; 1332 rq = &runq_pcpu[PCPU_GET(cpuid)]; 1333 } else { 1334 CTR1(KTR_RUNQ, "choosing kse %p from main runq", ke); 1335 } 1336 1337 #else 1338 rq = &runq; 1339 ke = runq_choose(&runq); 1340 #endif 1341 1342 if (ke != NULL) { 1343 runq_remove(rq, ke); 1344 ke->ke_state = KES_THREAD; 1345 1346 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1347 ("sched_choose: process swapped out")); 1348 } 1349 return (ke); 1350 } 1351 1352 void 1353 sched_userret(struct thread *td) 1354 { 1355 struct ksegrp *kg; 1356 /* 1357 * XXX we cheat slightly on the locking here to avoid locking in 1358 * the usual case. Setting td_priority here is essentially an 1359 * incomplete workaround for not setting it properly elsewhere. 1360 * Now that some interrupt handlers are threads, not setting it 1361 * properly elsewhere can clobber it in the window between setting 1362 * it here and returning to user mode, so don't waste time setting 1363 * it perfectly here. 1364 */ 1365 KASSERT((td->td_flags & TDF_BORROWING) == 0, 1366 ("thread with borrowed priority returning to userland")); 1367 kg = td->td_ksegrp; 1368 if (td->td_priority != kg->kg_user_pri) { 1369 mtx_lock_spin(&sched_lock); 1370 td->td_priority = kg->kg_user_pri; 1371 td->td_base_pri = kg->kg_user_pri; 1372 mtx_unlock_spin(&sched_lock); 1373 } 1374 } 1375 1376 void 1377 sched_bind(struct thread *td, int cpu) 1378 { 1379 struct kse *ke; 1380 1381 mtx_assert(&sched_lock, MA_OWNED); 1382 KASSERT(TD_IS_RUNNING(td), 1383 ("sched_bind: cannot bind non-running thread")); 1384 1385 ke = td->td_kse; 1386 1387 ke->ke_flags |= KEF_BOUND; 1388 #ifdef SMP 1389 ke->ke_runq = &runq_pcpu[cpu]; 1390 if (PCPU_GET(cpuid) == cpu) 1391 return; 1392 1393 ke->ke_state = KES_THREAD; 1394 1395 mi_switch(SW_VOL, NULL); 1396 #endif 1397 } 1398 1399 void 1400 sched_unbind(struct thread* td) 1401 { 1402 mtx_assert(&sched_lock, MA_OWNED); 1403 td->td_kse->ke_flags &= ~KEF_BOUND; 1404 } 1405 1406 int 1407 sched_is_bound(struct thread *td) 1408 { 1409 mtx_assert(&sched_lock, MA_OWNED); 1410 return (td->td_kse->ke_flags & KEF_BOUND); 1411 } 1412 1413 void 1414 sched_relinquish(struct thread *td) 1415 { 1416 struct ksegrp *kg; 1417 1418 kg = td->td_ksegrp; 1419 mtx_lock_spin(&sched_lock); 1420 if (kg->kg_pri_class == PRI_TIMESHARE) 1421 sched_prio(td, PRI_MAX_TIMESHARE); 1422 mi_switch(SW_VOL, NULL); 1423 mtx_unlock_spin(&sched_lock); 1424 } 1425 1426 int 1427 sched_load(void) 1428 { 1429 return (sched_tdcnt); 1430 } 1431 1432 int 1433 sched_sizeof_ksegrp(void) 1434 { 1435 return (sizeof(struct ksegrp) + sizeof(struct kg_sched)); 1436 } 1437 1438 int 1439 sched_sizeof_proc(void) 1440 { 1441 return (sizeof(struct proc)); 1442 } 1443 1444 int 1445 sched_sizeof_thread(void) 1446 { 1447 return (sizeof(struct thread) + sizeof(struct kse)); 1448 } 1449 1450 fixpt_t 1451 sched_pctcpu(struct thread *td) 1452 { 1453 struct kse *ke; 1454 1455 ke = td->td_kse; 1456 return (ke->ke_pctcpu); 1457 } 1458 1459 void 1460 sched_tick(void) 1461 { 1462 } 1463 #define KERN_SWITCH_INCLUDE 1 1464 #include "kern/kern_switch.c" 1465