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 #ifdef KSE 79 /* 80 * The schedulable entity that can be given a context to run. 81 * A process may have several of these. Probably one per processor 82 * but possibly a few more. In this universe they are grouped 83 * with a KSEG that contains the priority and niceness 84 * for the group. 85 */ 86 #else 87 /* 88 * The schedulable entity that runs a context. 89 * A process may have several of these. Probably one per processor 90 * but posibly a few more. 91 */ 92 #endif 93 struct kse { 94 TAILQ_ENTRY(kse) ke_procq; /* (j/z) Run queue. */ 95 struct thread *ke_thread; /* (*) Active associated thread. */ 96 fixpt_t ke_pctcpu; /* (j) %cpu during p_swtime. */ 97 u_char ke_rqindex; /* (j) Run queue index. */ 98 enum { 99 KES_THREAD = 0x0, /* slaved to thread state */ 100 KES_ONRUNQ 101 } ke_state; /* (j) KSE status. */ 102 int ke_cpticks; /* (j) Ticks of cpu time. */ 103 struct runq *ke_runq; /* runq the kse is currently on */ 104 }; 105 106 #ifdef KSE 107 #define ke_proc ke_thread->td_proc 108 #define ke_ksegrp ke_thread->td_ksegrp 109 #endif 110 111 #define td_kse td_sched 112 113 /* flags kept in td_flags */ 114 #define TDF_DIDRUN TDF_SCHED0 /* KSE actually ran. */ 115 #define TDF_EXIT TDF_SCHED1 /* KSE is being killed. */ 116 #define TDF_BOUND TDF_SCHED2 117 118 #define ke_flags ke_thread->td_flags 119 #define KEF_DIDRUN TDF_DIDRUN /* KSE actually ran. */ 120 #define KEF_EXIT TDF_EXIT /* KSE is being killed. */ 121 #define KEF_BOUND TDF_BOUND /* stuck to one CPU */ 122 123 #define SKE_RUNQ_PCPU(ke) \ 124 ((ke)->ke_runq != 0 && (ke)->ke_runq != &runq) 125 126 #ifdef KSE 127 struct kg_sched { 128 struct thread *skg_last_assigned; /* (j) Last thread assigned to */ 129 /* the system scheduler. */ 130 int skg_avail_opennings; /* (j) Num KSEs requested in group. */ 131 int skg_concurrency; /* (j) Num KSEs requested in group. */ 132 }; 133 #define kg_last_assigned kg_sched->skg_last_assigned 134 #define kg_avail_opennings kg_sched->skg_avail_opennings 135 #define kg_concurrency kg_sched->skg_concurrency 136 137 #define SLOT_RELEASE(kg) \ 138 do { \ 139 kg->kg_avail_opennings++; \ 140 CTR3(KTR_RUNQ, "kg %p(%d) Slot released (->%d)", \ 141 kg, \ 142 kg->kg_concurrency, \ 143 kg->kg_avail_opennings); \ 144 /* KASSERT((kg->kg_avail_opennings <= kg->kg_concurrency), \ 145 ("slots out of whack"));*/ \ 146 } while (0) 147 148 #define SLOT_USE(kg) \ 149 do { \ 150 kg->kg_avail_opennings--; \ 151 CTR3(KTR_RUNQ, "kg %p(%d) Slot used (->%d)", \ 152 kg, \ 153 kg->kg_concurrency, \ 154 kg->kg_avail_opennings); \ 155 /* KASSERT((kg->kg_avail_opennings >= 0), \ 156 ("slots out of whack"));*/ \ 157 } while (0) 158 #endif 159 160 /* 161 * KSE_CAN_MIGRATE macro returns true if the kse can migrate between 162 * cpus. 163 */ 164 #define KSE_CAN_MIGRATE(ke) \ 165 ((ke)->ke_thread->td_pinned == 0 && ((ke)->ke_flags & KEF_BOUND) == 0) 166 167 static struct kse kse0; 168 #ifdef KSE 169 static struct kg_sched kg_sched0; 170 #endif 171 172 static int sched_tdcnt; /* Total runnable threads in the system. */ 173 static int sched_quantum; /* Roundrobin scheduling quantum in ticks. */ 174 #define SCHED_QUANTUM (hz / 10) /* Default sched quantum */ 175 176 static struct callout roundrobin_callout; 177 178 #ifdef KSE 179 static void slot_fill(struct ksegrp *kg); 180 static struct kse *sched_choose(void); /* XXX Should be thread * */ 181 #else 182 static struct thread *sched_choose(void); 183 #endif 184 185 static void setup_runqs(void); 186 static void roundrobin(void *arg); 187 static void schedcpu(void); 188 static void schedcpu_thread(void); 189 static void sched_priority(struct thread *td, u_char prio); 190 static void sched_setup(void *dummy); 191 static void maybe_resched(struct thread *td); 192 #ifdef KSE 193 static void updatepri(struct ksegrp *kg); 194 static void resetpriority(struct ksegrp *kg); 195 static void resetpriority_thread(struct thread *td, struct ksegrp *kg); 196 #else 197 static void updatepri(struct thread *td); 198 static void resetpriority(struct thread *td); 199 static void resetpriority_thread(struct thread *td); 200 #endif 201 #ifdef SMP 202 static int forward_wakeup(int cpunum); 203 #endif 204 205 static struct kproc_desc sched_kp = { 206 "schedcpu", 207 schedcpu_thread, 208 NULL 209 }; 210 SYSINIT(schedcpu, SI_SUB_RUN_SCHEDULER, SI_ORDER_FIRST, kproc_start, &sched_kp) 211 SYSINIT(sched_setup, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, sched_setup, NULL) 212 213 /* 214 * Global run queue. 215 */ 216 static struct runq runq; 217 218 #ifdef SMP 219 /* 220 * Per-CPU run queues 221 */ 222 static struct runq runq_pcpu[MAXCPU]; 223 #endif 224 225 static void 226 setup_runqs(void) 227 { 228 #ifdef SMP 229 int i; 230 231 for (i = 0; i < MAXCPU; ++i) 232 runq_init(&runq_pcpu[i]); 233 #endif 234 235 runq_init(&runq); 236 } 237 238 static int 239 sysctl_kern_quantum(SYSCTL_HANDLER_ARGS) 240 { 241 int error, new_val; 242 243 new_val = sched_quantum * tick; 244 error = sysctl_handle_int(oidp, &new_val, 0, req); 245 if (error != 0 || req->newptr == NULL) 246 return (error); 247 if (new_val < tick) 248 return (EINVAL); 249 sched_quantum = new_val / tick; 250 hogticks = 2 * sched_quantum; 251 return (0); 252 } 253 254 SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RD, 0, "Scheduler"); 255 256 SYSCTL_STRING(_kern_sched, OID_AUTO, name, CTLFLAG_RD, "4BSD", 0, 257 "Scheduler name"); 258 259 SYSCTL_PROC(_kern_sched, OID_AUTO, quantum, CTLTYPE_INT | CTLFLAG_RW, 260 0, sizeof sched_quantum, sysctl_kern_quantum, "I", 261 "Roundrobin scheduling quantum in microseconds"); 262 263 #ifdef SMP 264 /* Enable forwarding of wakeups to all other cpus */ 265 SYSCTL_NODE(_kern_sched, OID_AUTO, ipiwakeup, CTLFLAG_RD, NULL, "Kernel SMP"); 266 267 static int forward_wakeup_enabled = 1; 268 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, enabled, CTLFLAG_RW, 269 &forward_wakeup_enabled, 0, 270 "Forwarding of wakeup to idle CPUs"); 271 272 static int forward_wakeups_requested = 0; 273 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, requested, CTLFLAG_RD, 274 &forward_wakeups_requested, 0, 275 "Requests for Forwarding of wakeup to idle CPUs"); 276 277 static int forward_wakeups_delivered = 0; 278 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, delivered, CTLFLAG_RD, 279 &forward_wakeups_delivered, 0, 280 "Completed Forwarding of wakeup to idle CPUs"); 281 282 static int forward_wakeup_use_mask = 1; 283 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, usemask, CTLFLAG_RW, 284 &forward_wakeup_use_mask, 0, 285 "Use the mask of idle cpus"); 286 287 static int forward_wakeup_use_loop = 0; 288 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, useloop, CTLFLAG_RW, 289 &forward_wakeup_use_loop, 0, 290 "Use a loop to find idle cpus"); 291 292 static int forward_wakeup_use_single = 0; 293 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, onecpu, CTLFLAG_RW, 294 &forward_wakeup_use_single, 0, 295 "Only signal one idle cpu"); 296 297 static int forward_wakeup_use_htt = 0; 298 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, htt2, CTLFLAG_RW, 299 &forward_wakeup_use_htt, 0, 300 "account for htt"); 301 302 #endif 303 #ifdef KSE 304 static int sched_followon = 0; 305 SYSCTL_INT(_kern_sched, OID_AUTO, followon, CTLFLAG_RW, 306 &sched_followon, 0, 307 "allow threads to share a quantum"); 308 309 static int sched_pfollowons = 0; 310 SYSCTL_INT(_kern_sched, OID_AUTO, pfollowons, CTLFLAG_RD, 311 &sched_pfollowons, 0, 312 "number of followons done to a different ksegrp"); 313 314 static int sched_kgfollowons = 0; 315 SYSCTL_INT(_kern_sched, OID_AUTO, kgfollowons, CTLFLAG_RD, 316 &sched_kgfollowons, 0, 317 "number of followons done in a ksegrp"); 318 #endif 319 320 static __inline void 321 sched_load_add(void) 322 { 323 sched_tdcnt++; 324 CTR1(KTR_SCHED, "global load: %d", sched_tdcnt); 325 } 326 327 static __inline void 328 sched_load_rem(void) 329 { 330 sched_tdcnt--; 331 CTR1(KTR_SCHED, "global load: %d", sched_tdcnt); 332 } 333 /* 334 * Arrange to reschedule if necessary, taking the priorities and 335 * schedulers into account. 336 */ 337 static void 338 maybe_resched(struct thread *td) 339 { 340 341 mtx_assert(&sched_lock, MA_OWNED); 342 if (td->td_priority < curthread->td_priority) 343 curthread->td_flags |= TDF_NEEDRESCHED; 344 } 345 346 /* 347 * Force switch among equal priority processes every 100ms. 348 * We don't actually need to force a context switch of the current process. 349 * The act of firing the event triggers a context switch to softclock() and 350 * then switching back out again which is equivalent to a preemption, thus 351 * no further work is needed on the local CPU. 352 */ 353 /* ARGSUSED */ 354 static void 355 roundrobin(void *arg) 356 { 357 358 #ifdef SMP 359 mtx_lock_spin(&sched_lock); 360 forward_roundrobin(); 361 mtx_unlock_spin(&sched_lock); 362 #endif 363 364 callout_reset(&roundrobin_callout, sched_quantum, roundrobin, NULL); 365 } 366 367 /* 368 * Constants for digital decay and forget: 369 * ifdef KSE 370 * 90% of (kg_estcpu) usage in 5 * loadav time 371 * else 372 * 90% of (td_estcpu) usage in 5 * loadav time 373 * endif 374 * 95% of (ke_pctcpu) usage in 60 seconds (load insensitive) 375 * Note that, as ps(1) mentions, this can let percentages 376 * total over 100% (I've seen 137.9% for 3 processes). 377 * 378 * ifdef KSE 379 * Note that schedclock() updates kg_estcpu and p_cpticks asynchronously. 380 * else 381 * Note that schedclock() updates td_estcpu and p_cpticks asynchronously. 382 * endif 383 * 384 * ifdef KSE 385 * We wish to decay away 90% of kg_estcpu in (5 * loadavg) seconds. 386 * else 387 * We wish to decay away 90% of td_estcpu in (5 * loadavg) seconds. 388 * endif 389 * That is, the system wants to compute a value of decay such 390 * that the following for loop: 391 * for (i = 0; i < (5 * loadavg); i++) 392 * ifdef KSE 393 * kg_estcpu *= decay; 394 * else 395 * td_estcpu *= decay; 396 * endif 397 * will compute 398 * ifdef KSE 399 * kg_estcpu *= 0.1; 400 * else 401 * td_estcpu *= 0.1; 402 * endif 403 * for all values of loadavg: 404 * 405 * Mathematically this loop can be expressed by saying: 406 * decay ** (5 * loadavg) ~= .1 407 * 408 * The system computes decay as: 409 * decay = (2 * loadavg) / (2 * loadavg + 1) 410 * 411 * We wish to prove that the system's computation of decay 412 * will always fulfill the equation: 413 * decay ** (5 * loadavg) ~= .1 414 * 415 * If we compute b as: 416 * b = 2 * loadavg 417 * then 418 * decay = b / (b + 1) 419 * 420 * We now need to prove two things: 421 * 1) Given factor ** (5 * loadavg) ~= .1, prove factor == b/(b+1) 422 * 2) Given b/(b+1) ** power ~= .1, prove power == (5 * loadavg) 423 * 424 * Facts: 425 * For x close to zero, exp(x) =~ 1 + x, since 426 * exp(x) = 0! + x**1/1! + x**2/2! + ... . 427 * therefore exp(-1/b) =~ 1 - (1/b) = (b-1)/b. 428 * For x close to zero, ln(1+x) =~ x, since 429 * ln(1+x) = x - x**2/2 + x**3/3 - ... -1 < x < 1 430 * therefore ln(b/(b+1)) = ln(1 - 1/(b+1)) =~ -1/(b+1). 431 * ln(.1) =~ -2.30 432 * 433 * Proof of (1): 434 * Solve (factor)**(power) =~ .1 given power (5*loadav): 435 * solving for factor, 436 * ln(factor) =~ (-2.30/5*loadav), or 437 * factor =~ exp(-1/((5/2.30)*loadav)) =~ exp(-1/(2*loadav)) = 438 * exp(-1/b) =~ (b-1)/b =~ b/(b+1). QED 439 * 440 * Proof of (2): 441 * Solve (factor)**(power) =~ .1 given factor == (b/(b+1)): 442 * solving for power, 443 * power*ln(b/(b+1)) =~ -2.30, or 444 * power =~ 2.3 * (b + 1) = 4.6*loadav + 2.3 =~ 5*loadav. QED 445 * 446 * Actual power values for the implemented algorithm are as follows: 447 * loadav: 1 2 3 4 448 * power: 5.68 10.32 14.94 19.55 449 */ 450 451 /* calculations for digital decay to forget 90% of usage in 5*loadav sec */ 452 #define loadfactor(loadav) (2 * (loadav)) 453 #define decay_cpu(loadfac, cpu) (((loadfac) * (cpu)) / ((loadfac) + FSCALE)) 454 455 /* decay 95% of `ke_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */ 456 static fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */ 457 SYSCTL_INT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, ""); 458 459 /* 460 * If `ccpu' is not equal to `exp(-1/20)' and you still want to use the 461 * faster/more-accurate formula, you'll have to estimate CCPU_SHIFT below 462 * and possibly adjust FSHIFT in "param.h" so that (FSHIFT >= CCPU_SHIFT). 463 * 464 * To estimate CCPU_SHIFT for exp(-1/20), the following formula was used: 465 * 1 - exp(-1/20) ~= 0.0487 ~= 0.0488 == 1 (fixed pt, *11* bits). 466 * 467 * If you don't want to bother with the faster/more-accurate formula, you 468 * can set CCPU_SHIFT to (FSHIFT + 1) which will use a slower/less-accurate 469 * (more general) method of calculating the %age of CPU used by a process. 470 */ 471 #define CCPU_SHIFT 11 472 473 /* 474 * Recompute process priorities, every hz ticks. 475 * MP-safe, called without the Giant mutex. 476 */ 477 /* ARGSUSED */ 478 static void 479 schedcpu(void) 480 { 481 register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]); 482 struct thread *td; 483 struct proc *p; 484 struct kse *ke; 485 #ifdef KSE 486 struct ksegrp *kg; 487 #endif 488 int awake, realstathz; 489 490 realstathz = stathz ? stathz : hz; 491 sx_slock(&allproc_lock); 492 FOREACH_PROC_IN_SYSTEM(p) { 493 /* 494 * Prevent state changes and protect run queue. 495 */ 496 mtx_lock_spin(&sched_lock); 497 /* 498 * Increment time in/out of memory. We ignore overflow; with 499 * 16-bit int's (remember them?) overflow takes 45 days. 500 */ 501 p->p_swtime++; 502 #ifdef KSE 503 FOREACH_KSEGRP_IN_PROC(p, kg) { 504 #else 505 FOREACH_THREAD_IN_PROC(p, td) { 506 #endif 507 awake = 0; 508 #ifdef KSE 509 FOREACH_THREAD_IN_GROUP(kg, td) { 510 ke = td->td_kse; 511 /* 512 * Increment sleep time (if sleeping). We 513 * ignore overflow, as above. 514 */ 515 /* 516 * The kse slptimes are not touched in wakeup 517 * because the thread may not HAVE a KSE. 518 */ 519 if (ke->ke_state == KES_ONRUNQ) { 520 awake = 1; 521 ke->ke_flags &= ~KEF_DIDRUN; 522 } else if ((ke->ke_state == KES_THREAD) && 523 (TD_IS_RUNNING(td))) { 524 awake = 1; 525 /* Do not clear KEF_DIDRUN */ 526 } else if (ke->ke_flags & KEF_DIDRUN) { 527 awake = 1; 528 ke->ke_flags &= ~KEF_DIDRUN; 529 } 530 531 /* 532 * ke_pctcpu is only for ps and ttyinfo(). 533 * Do it per kse, and add them up at the end? 534 * XXXKSE 535 */ 536 ke->ke_pctcpu = (ke->ke_pctcpu * ccpu) >> 537 FSHIFT; 538 /* 539 * If the kse has been idle the entire second, 540 * stop recalculating its priority until 541 * it wakes up. 542 */ 543 if (ke->ke_cpticks == 0) 544 continue; 545 #if (FSHIFT >= CCPU_SHIFT) 546 ke->ke_pctcpu += (realstathz == 100) 547 ? ((fixpt_t) ke->ke_cpticks) << 548 (FSHIFT - CCPU_SHIFT) : 549 100 * (((fixpt_t) ke->ke_cpticks) 550 << (FSHIFT - CCPU_SHIFT)) / realstathz; 551 #else 552 ke->ke_pctcpu += ((FSCALE - ccpu) * 553 (ke->ke_cpticks * 554 FSCALE / realstathz)) >> FSHIFT; 555 #endif 556 ke->ke_cpticks = 0; 557 } /* end of kse loop */ 558 #else 559 ke = td->td_kse; 560 /* 561 * Increment sleep time (if sleeping). We 562 * ignore overflow, as above. 563 */ 564 /* 565 * The kse slptimes are not touched in wakeup 566 * because the thread may not HAVE a KSE. 567 */ 568 if (ke->ke_state == KES_ONRUNQ) { 569 awake = 1; 570 ke->ke_flags &= ~KEF_DIDRUN; 571 } else if ((ke->ke_state == KES_THREAD) && 572 (TD_IS_RUNNING(td))) { 573 awake = 1; 574 /* Do not clear KEF_DIDRUN */ 575 } else if (ke->ke_flags & KEF_DIDRUN) { 576 awake = 1; 577 ke->ke_flags &= ~KEF_DIDRUN; 578 } 579 580 /* 581 * ke_pctcpu is only for ps and ttyinfo(). 582 * Do it per kse, and add them up at the end? 583 * XXXKSE 584 */ 585 ke->ke_pctcpu = (ke->ke_pctcpu * ccpu) >> 586 FSHIFT; 587 /* 588 * If the kse has been idle the entire second, 589 * stop recalculating its priority until 590 * it wakes up. 591 */ 592 if (ke->ke_cpticks == 0) 593 continue; 594 #if (FSHIFT >= CCPU_SHIFT) 595 ke->ke_pctcpu += (realstathz == 100) 596 ? ((fixpt_t) ke->ke_cpticks) << 597 (FSHIFT - CCPU_SHIFT) : 598 100 * (((fixpt_t) ke->ke_cpticks) 599 << (FSHIFT - CCPU_SHIFT)) / realstathz; 600 #else 601 ke->ke_pctcpu += ((FSCALE - ccpu) * 602 (ke->ke_cpticks * 603 FSCALE / realstathz)) >> FSHIFT; 604 #endif 605 ke->ke_cpticks = 0; 606 #endif 607 608 /* 609 * ifdef KSE 610 * If there are ANY running threads in this KSEGRP, 611 * else 612 * If there are ANY running threads in this process, 613 * endif 614 * then don't count it as sleeping. 615 */ 616 if (awake) { 617 #ifdef KSE 618 if (kg->kg_slptime > 1) { 619 #else 620 if (td->td_slptime > 1) { 621 #endif 622 /* 623 * In an ideal world, this should not 624 * happen, because whoever woke us 625 * up from the long sleep should have 626 * unwound the slptime and reset our 627 * priority before we run at the stale 628 * priority. Should KASSERT at some 629 * point when all the cases are fixed. 630 */ 631 #ifdef KSE 632 updatepri(kg); 633 } 634 kg->kg_slptime = 0; 635 } else 636 kg->kg_slptime++; 637 if (kg->kg_slptime > 1) 638 continue; 639 kg->kg_estcpu = decay_cpu(loadfac, kg->kg_estcpu); 640 resetpriority(kg); 641 FOREACH_THREAD_IN_GROUP(kg, td) { 642 resetpriority_thread(td, kg); 643 } 644 } /* end of ksegrp loop */ 645 #else 646 updatepri(td); 647 } 648 td->td_slptime = 0; 649 } else 650 td->td_slptime++; 651 if (td->td_slptime > 1) 652 continue; 653 td->td_estcpu = decay_cpu(loadfac, td->td_estcpu); 654 resetpriority(td); 655 resetpriority_thread(td); 656 } /* end of thread loop */ 657 #endif 658 mtx_unlock_spin(&sched_lock); 659 } /* end of process loop */ 660 sx_sunlock(&allproc_lock); 661 } 662 663 /* 664 * Main loop for a kthread that executes schedcpu once a second. 665 */ 666 static void 667 schedcpu_thread(void) 668 { 669 int nowake; 670 671 for (;;) { 672 schedcpu(); 673 tsleep(&nowake, 0, "-", hz); 674 } 675 } 676 677 /* 678 * Recalculate the priority of a process after it has slept for a while. 679 * ifdef KSE 680 * For all load averages >= 1 and max kg_estcpu of 255, sleeping for at 681 * least six times the loadfactor will decay kg_estcpu to zero. 682 * else 683 * For all load averages >= 1 and max td_estcpu of 255, sleeping for at 684 * least six times the loadfactor will decay td_estcpu to zero. 685 * endif 686 */ 687 static void 688 #ifdef KSE 689 updatepri(struct ksegrp *kg) 690 #else 691 updatepri(struct thread *td) 692 #endif 693 { 694 register fixpt_t loadfac; 695 register unsigned int newcpu; 696 697 loadfac = loadfactor(averunnable.ldavg[0]); 698 #ifdef KSE 699 if (kg->kg_slptime > 5 * loadfac) 700 kg->kg_estcpu = 0; 701 #else 702 if (td->td_slptime > 5 * loadfac) 703 td->td_estcpu = 0; 704 #endif 705 else { 706 #ifdef KSE 707 newcpu = kg->kg_estcpu; 708 kg->kg_slptime--; /* was incremented in schedcpu() */ 709 while (newcpu && --kg->kg_slptime) 710 #else 711 newcpu = td->td_estcpu; 712 td->td_slptime--; /* was incremented in schedcpu() */ 713 while (newcpu && --td->td_slptime) 714 #endif 715 newcpu = decay_cpu(loadfac, newcpu); 716 #ifdef KSE 717 kg->kg_estcpu = newcpu; 718 #else 719 td->td_estcpu = newcpu; 720 #endif 721 } 722 } 723 724 /* 725 * Compute the priority of a process when running in user mode. 726 * Arrange to reschedule if the resulting priority is better 727 * than that of the current process. 728 */ 729 static void 730 #ifdef KSE 731 resetpriority(struct ksegrp *kg) 732 #else 733 resetpriority(struct thread *td) 734 #endif 735 { 736 register unsigned int newpriority; 737 738 #ifdef KSE 739 if (kg->kg_pri_class == PRI_TIMESHARE) { 740 newpriority = PUSER + kg->kg_estcpu / INVERSE_ESTCPU_WEIGHT + 741 NICE_WEIGHT * (kg->kg_proc->p_nice - PRIO_MIN); 742 #else 743 if (td->td_pri_class == PRI_TIMESHARE) { 744 newpriority = PUSER + td->td_estcpu / INVERSE_ESTCPU_WEIGHT + 745 NICE_WEIGHT * (td->td_proc->p_nice - PRIO_MIN); 746 #endif 747 newpriority = min(max(newpriority, PRI_MIN_TIMESHARE), 748 PRI_MAX_TIMESHARE); 749 #ifdef KSE 750 sched_user_prio(kg, newpriority); 751 #else 752 sched_user_prio(td, newpriority); 753 #endif 754 } 755 } 756 757 /* 758 * Update the thread's priority when the associated ksegroup's user 759 * priority changes. 760 */ 761 static void 762 #ifdef KSE 763 resetpriority_thread(struct thread *td, struct ksegrp *kg) 764 #else 765 resetpriority_thread(struct thread *td) 766 #endif 767 { 768 769 /* Only change threads with a time sharing user priority. */ 770 if (td->td_priority < PRI_MIN_TIMESHARE || 771 td->td_priority > PRI_MAX_TIMESHARE) 772 return; 773 774 /* XXX the whole needresched thing is broken, but not silly. */ 775 maybe_resched(td); 776 777 #ifdef KSE 778 sched_prio(td, kg->kg_user_pri); 779 #else 780 sched_prio(td, td->td_user_pri); 781 #endif 782 } 783 784 /* ARGSUSED */ 785 static void 786 sched_setup(void *dummy) 787 { 788 setup_runqs(); 789 790 if (sched_quantum == 0) 791 sched_quantum = SCHED_QUANTUM; 792 hogticks = 2 * sched_quantum; 793 794 callout_init(&roundrobin_callout, CALLOUT_MPSAFE); 795 796 /* Kick off timeout driven events by calling first time. */ 797 roundrobin(NULL); 798 799 /* Account for thread0. */ 800 sched_load_add(); 801 } 802 803 /* External interfaces start here */ 804 /* 805 * Very early in the boot some setup of scheduler-specific 806 * parts of proc0 and of some scheduler resources needs to be done. 807 * Called from: 808 * proc0_init() 809 */ 810 void 811 schedinit(void) 812 { 813 /* 814 * Set up the scheduler specific parts of proc0. 815 */ 816 proc0.p_sched = NULL; /* XXX */ 817 #ifdef KSE 818 ksegrp0.kg_sched = &kg_sched0; 819 #endif 820 thread0.td_sched = &kse0; 821 kse0.ke_thread = &thread0; 822 kse0.ke_state = KES_THREAD; 823 #ifdef KSE 824 kg_sched0.skg_concurrency = 1; 825 kg_sched0.skg_avail_opennings = 0; /* we are already running */ 826 #endif 827 } 828 829 int 830 sched_runnable(void) 831 { 832 #ifdef SMP 833 return runq_check(&runq) + runq_check(&runq_pcpu[PCPU_GET(cpuid)]); 834 #else 835 return runq_check(&runq); 836 #endif 837 } 838 839 int 840 sched_rr_interval(void) 841 { 842 if (sched_quantum == 0) 843 sched_quantum = SCHED_QUANTUM; 844 return (sched_quantum); 845 } 846 847 /* 848 * We adjust the priority of the current process. The priority of 849 * a process gets worse as it accumulates CPU time. The cpu usage 850 * ifdef KSE 851 * estimator (kg_estcpu) is increased here. resetpriority() will 852 * compute a different priority each time kg_estcpu increases by 853 * else 854 * estimator (td_estcpu) is increased here. resetpriority() will 855 * compute a different priority each time td_estcpu increases by 856 * endif 857 * INVERSE_ESTCPU_WEIGHT 858 * (until MAXPRI is reached). The cpu usage estimator ramps up 859 * quite quickly when the process is running (linearly), and decays 860 * away exponentially, at a rate which is proportionally slower when 861 * the system is busy. The basic principle is that the system will 862 * 90% forget that the process used a lot of CPU time in 5 * loadav 863 * seconds. This causes the system to favor processes which haven't 864 * run much recently, and to round-robin among other processes. 865 */ 866 void 867 sched_clock(struct thread *td) 868 { 869 #ifdef KSE 870 struct ksegrp *kg; 871 #endif 872 struct kse *ke; 873 874 mtx_assert(&sched_lock, MA_OWNED); 875 #ifdef KSE 876 kg = td->td_ksegrp; 877 #endif 878 ke = td->td_kse; 879 880 ke->ke_cpticks++; 881 #ifdef KSE 882 kg->kg_estcpu = ESTCPULIM(kg->kg_estcpu + 1); 883 if ((kg->kg_estcpu % INVERSE_ESTCPU_WEIGHT) == 0) { 884 resetpriority(kg); 885 resetpriority_thread(td, kg); 886 #else 887 td->td_estcpu = ESTCPULIM(td->td_estcpu + 1); 888 if ((td->td_estcpu % INVERSE_ESTCPU_WEIGHT) == 0) { 889 resetpriority(td); 890 resetpriority_thread(td); 891 #endif 892 } 893 } 894 895 #ifdef KSE 896 /* 897 * charge childs scheduling cpu usage to parent. 898 * 899 * XXXKSE assume only one thread & kse & ksegrp keep estcpu in each ksegrp. 900 * Charge it to the ksegrp that did the wait since process estcpu is sum of 901 * all ksegrps, this is strictly as expected. Assume that the child process 902 * aggregated all the estcpu into the 'built-in' ksegrp. 903 */ 904 #else 905 /* 906 * charge childs scheduling cpu usage to parent. 907 */ 908 #endif 909 void 910 sched_exit(struct proc *p, struct thread *td) 911 { 912 #ifdef KSE 913 sched_exit_ksegrp(FIRST_KSEGRP_IN_PROC(p), td); 914 sched_exit_thread(FIRST_THREAD_IN_PROC(p), td); 915 #else 916 struct thread *parent = FIRST_THREAD_IN_PROC(p); 917 918 CTR3(KTR_SCHED, "sched_exit: %p(%s) prio %d", 919 td, td->td_proc->p_comm, td->td_priority); 920 921 parent->td_estcpu = ESTCPULIM(parent->td_estcpu + td->td_estcpu); 922 if ((td->td_proc->p_flag & P_NOLOAD) == 0) 923 sched_load_rem(); 924 #endif 925 } 926 927 #ifdef KSE 928 void 929 sched_exit_ksegrp(struct ksegrp *kg, struct thread *childtd) 930 { 931 932 mtx_assert(&sched_lock, MA_OWNED); 933 kg->kg_estcpu = ESTCPULIM(kg->kg_estcpu + childtd->td_ksegrp->kg_estcpu); 934 } 935 936 void 937 sched_exit_thread(struct thread *td, struct thread *child) 938 { 939 CTR3(KTR_SCHED, "sched_exit_thread: %p(%s) prio %d", 940 child, child->td_proc->p_comm, child->td_priority); 941 if ((child->td_proc->p_flag & P_NOLOAD) == 0) 942 sched_load_rem(); 943 } 944 #endif 945 946 void 947 sched_fork(struct thread *td, struct thread *childtd) 948 { 949 #ifdef KSE 950 sched_fork_ksegrp(td, childtd->td_ksegrp); 951 sched_fork_thread(td, childtd); 952 #else 953 childtd->td_estcpu = td->td_estcpu; 954 sched_newthread(childtd); 955 #endif 956 } 957 958 #ifdef KSE 959 void 960 sched_fork_ksegrp(struct thread *td, struct ksegrp *child) 961 { 962 mtx_assert(&sched_lock, MA_OWNED); 963 child->kg_estcpu = td->td_ksegrp->kg_estcpu; 964 } 965 966 void 967 sched_fork_thread(struct thread *td, struct thread *childtd) 968 { 969 sched_newthread(childtd); 970 } 971 #endif 972 973 void 974 sched_nice(struct proc *p, int nice) 975 { 976 #ifdef KSE 977 struct ksegrp *kg; 978 #endif 979 struct thread *td; 980 981 PROC_LOCK_ASSERT(p, MA_OWNED); 982 mtx_assert(&sched_lock, MA_OWNED); 983 p->p_nice = nice; 984 #ifdef KSE 985 FOREACH_KSEGRP_IN_PROC(p, kg) { 986 resetpriority(kg); 987 FOREACH_THREAD_IN_GROUP(kg, td) { 988 resetpriority_thread(td, kg); 989 } 990 } 991 #else 992 FOREACH_THREAD_IN_PROC(p, td) { 993 resetpriority(td); 994 resetpriority_thread(td); 995 } 996 #endif 997 } 998 999 void 1000 #ifdef KSE 1001 sched_class(struct ksegrp *kg, int class) 1002 #else 1003 sched_class(struct thread *td, int class) 1004 #endif 1005 { 1006 mtx_assert(&sched_lock, MA_OWNED); 1007 #ifdef KSE 1008 kg->kg_pri_class = class; 1009 #else 1010 td->td_pri_class = class; 1011 #endif 1012 } 1013 1014 #ifdef KSE 1015 /* 1016 * Adjust the priority of a thread. 1017 * This may include moving the thread within the KSEGRP, 1018 * changing the assignment of a kse to the thread, 1019 * and moving a KSE in the system run queue. 1020 */ 1021 #else 1022 /* 1023 * Adjust the priority of a thread. 1024 */ 1025 #endif 1026 static void 1027 sched_priority(struct thread *td, u_char prio) 1028 { 1029 CTR6(KTR_SCHED, "sched_prio: %p(%s) prio %d newprio %d by %p(%s)", 1030 td, td->td_proc->p_comm, td->td_priority, prio, curthread, 1031 curthread->td_proc->p_comm); 1032 1033 mtx_assert(&sched_lock, MA_OWNED); 1034 if (td->td_priority == prio) 1035 return; 1036 if (TD_ON_RUNQ(td)) { 1037 adjustrunqueue(td, prio); 1038 } else { 1039 td->td_priority = prio; 1040 } 1041 } 1042 1043 /* 1044 * Update a thread's priority when it is lent another thread's 1045 * priority. 1046 */ 1047 void 1048 sched_lend_prio(struct thread *td, u_char prio) 1049 { 1050 1051 td->td_flags |= TDF_BORROWING; 1052 sched_priority(td, prio); 1053 } 1054 1055 /* 1056 * Restore a thread's priority when priority propagation is 1057 * over. The prio argument is the minimum priority the thread 1058 * needs to have to satisfy other possible priority lending 1059 * requests. If the thread's regulary priority is less 1060 * important than prio the thread will keep a priority boost 1061 * of prio. 1062 */ 1063 void 1064 sched_unlend_prio(struct thread *td, u_char prio) 1065 { 1066 u_char base_pri; 1067 1068 if (td->td_base_pri >= PRI_MIN_TIMESHARE && 1069 td->td_base_pri <= PRI_MAX_TIMESHARE) 1070 #ifdef KSE 1071 base_pri = td->td_ksegrp->kg_user_pri; 1072 #else 1073 base_pri = td->td_user_pri; 1074 #endif 1075 else 1076 base_pri = td->td_base_pri; 1077 if (prio >= base_pri) { 1078 td->td_flags &= ~TDF_BORROWING; 1079 sched_prio(td, base_pri); 1080 } else 1081 sched_lend_prio(td, prio); 1082 } 1083 1084 void 1085 sched_prio(struct thread *td, u_char prio) 1086 { 1087 u_char oldprio; 1088 1089 /* First, update the base priority. */ 1090 td->td_base_pri = prio; 1091 1092 /* 1093 * If the thread is borrowing another thread's priority, don't ever 1094 * lower the priority. 1095 */ 1096 if (td->td_flags & TDF_BORROWING && td->td_priority < prio) 1097 return; 1098 1099 /* Change the real priority. */ 1100 oldprio = td->td_priority; 1101 sched_priority(td, prio); 1102 1103 /* 1104 * If the thread is on a turnstile, then let the turnstile update 1105 * its state. 1106 */ 1107 if (TD_ON_LOCK(td) && oldprio != prio) 1108 turnstile_adjust(td, oldprio); 1109 } 1110 1111 void 1112 #ifdef KSE 1113 sched_user_prio(struct ksegrp *kg, u_char prio) 1114 #else 1115 sched_user_prio(struct thread *td, u_char prio) 1116 #endif 1117 { 1118 #ifdef KSE 1119 struct thread *td; 1120 #endif 1121 u_char oldprio; 1122 1123 #ifdef KSE 1124 kg->kg_base_user_pri = prio; 1125 1126 /* XXXKSE only for 1:1 */ 1127 1128 td = TAILQ_FIRST(&kg->kg_threads); 1129 if (td == NULL) { 1130 kg->kg_user_pri = prio; 1131 return; 1132 } 1133 1134 if (td->td_flags & TDF_UBORROWING && kg->kg_user_pri <= prio) 1135 return; 1136 1137 oldprio = kg->kg_user_pri; 1138 kg->kg_user_pri = prio; 1139 #else 1140 td->td_base_user_pri = prio; 1141 1142 oldprio = td->td_user_pri; 1143 td->td_user_pri = prio; 1144 #endif 1145 1146 if (TD_ON_UPILOCK(td) && oldprio != prio) 1147 umtx_pi_adjust(td, oldprio); 1148 } 1149 1150 void 1151 sched_lend_user_prio(struct thread *td, u_char prio) 1152 { 1153 u_char oldprio; 1154 1155 td->td_flags |= TDF_UBORROWING; 1156 1157 #ifdef KSE 1158 oldprio = td->td_ksegrp->kg_user_pri; 1159 td->td_ksegrp->kg_user_pri = prio; 1160 #else 1161 oldprio = td->td_user_pri; 1162 td->td_user_pri = prio; 1163 #endif 1164 1165 if (TD_ON_UPILOCK(td) && oldprio != prio) 1166 umtx_pi_adjust(td, oldprio); 1167 } 1168 1169 void 1170 sched_unlend_user_prio(struct thread *td, u_char prio) 1171 { 1172 #ifdef KSE 1173 struct ksegrp *kg = td->td_ksegrp; 1174 #endif 1175 u_char base_pri; 1176 1177 #ifdef KSE 1178 base_pri = kg->kg_base_user_pri; 1179 #else 1180 base_pri = td->td_base_user_pri; 1181 #endif 1182 if (prio >= base_pri) { 1183 td->td_flags &= ~TDF_UBORROWING; 1184 #ifdef KSE 1185 sched_user_prio(kg, base_pri); 1186 #else 1187 sched_user_prio(td, base_pri); 1188 #endif 1189 } else 1190 sched_lend_user_prio(td, prio); 1191 } 1192 1193 void 1194 sched_sleep(struct thread *td) 1195 { 1196 1197 mtx_assert(&sched_lock, MA_OWNED); 1198 #ifdef KSE 1199 td->td_ksegrp->kg_slptime = 0; 1200 #else 1201 td->td_slptime = 0; 1202 #endif 1203 } 1204 1205 #ifdef KSE 1206 static void remrunqueue(struct thread *td); 1207 #endif 1208 1209 void 1210 sched_switch(struct thread *td, struct thread *newtd, int flags) 1211 { 1212 struct kse *ke; 1213 #ifdef KSE 1214 struct ksegrp *kg; 1215 #endif 1216 struct proc *p; 1217 1218 ke = td->td_kse; 1219 p = td->td_proc; 1220 1221 mtx_assert(&sched_lock, MA_OWNED); 1222 1223 if ((p->p_flag & P_NOLOAD) == 0) 1224 sched_load_rem(); 1225 #ifdef KSE 1226 /* 1227 * We are volunteering to switch out so we get to nominate 1228 * a successor for the rest of our quantum 1229 * First try another thread in our ksegrp, and then look for 1230 * other ksegrps in our process. 1231 */ 1232 if (sched_followon && 1233 (p->p_flag & P_HADTHREADS) && 1234 (flags & SW_VOL) && 1235 newtd == NULL) { 1236 /* lets schedule another thread from this process */ 1237 kg = td->td_ksegrp; 1238 if ((newtd = TAILQ_FIRST(&kg->kg_runq))) { 1239 remrunqueue(newtd); 1240 sched_kgfollowons++; 1241 } else { 1242 FOREACH_KSEGRP_IN_PROC(p, kg) { 1243 if ((newtd = TAILQ_FIRST(&kg->kg_runq))) { 1244 sched_pfollowons++; 1245 remrunqueue(newtd); 1246 break; 1247 } 1248 } 1249 } 1250 } 1251 #endif 1252 1253 if (newtd) 1254 newtd->td_flags |= (td->td_flags & TDF_NEEDRESCHED); 1255 1256 td->td_lastcpu = td->td_oncpu; 1257 td->td_flags &= ~TDF_NEEDRESCHED; 1258 td->td_owepreempt = 0; 1259 td->td_oncpu = NOCPU; 1260 /* 1261 * At the last moment, if this thread is still marked RUNNING, 1262 * then put it back on the run queue as it has not been suspended 1263 * or stopped or any thing else similar. We never put the idle 1264 * threads on the run queue, however. 1265 */ 1266 if (td == PCPU_GET(idlethread)) 1267 TD_SET_CAN_RUN(td); 1268 else { 1269 #ifdef KSE 1270 SLOT_RELEASE(td->td_ksegrp); 1271 #endif 1272 if (TD_IS_RUNNING(td)) { 1273 /* Put us back on the run queue (kse and all). */ 1274 setrunqueue(td, (flags & SW_PREEMPT) ? 1275 SRQ_OURSELF|SRQ_YIELDING|SRQ_PREEMPTED : 1276 SRQ_OURSELF|SRQ_YIELDING); 1277 #ifdef KSE 1278 } else if (p->p_flag & P_HADTHREADS) { 1279 /* 1280 * We will not be on the run queue. So we must be 1281 * sleeping or similar. As it's available, 1282 * someone else can use the KSE if they need it. 1283 * It's NOT available if we are about to need it 1284 */ 1285 if (newtd == NULL || newtd->td_ksegrp != td->td_ksegrp) 1286 slot_fill(td->td_ksegrp); 1287 #endif 1288 } 1289 } 1290 if (newtd) { 1291 /* 1292 * The thread we are about to run needs to be counted 1293 * as if it had been added to the run queue and selected. 1294 * It came from: 1295 * * A preemption 1296 * ifdef KSE 1297 * * An upcall 1298 * endif 1299 * * A followon 1300 */ 1301 KASSERT((newtd->td_inhibitors == 0), 1302 ("trying to run inhibitted thread")); 1303 #ifdef KSE 1304 SLOT_USE(newtd->td_ksegrp); 1305 #endif 1306 newtd->td_kse->ke_flags |= KEF_DIDRUN; 1307 TD_SET_RUNNING(newtd); 1308 if ((newtd->td_proc->p_flag & P_NOLOAD) == 0) 1309 sched_load_add(); 1310 } else { 1311 newtd = choosethread(); 1312 } 1313 1314 if (td != newtd) { 1315 #ifdef HWPMC_HOOKS 1316 if (PMC_PROC_IS_USING_PMCS(td->td_proc)) 1317 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT); 1318 #endif 1319 1320 cpu_switch(td, newtd); 1321 #ifdef HWPMC_HOOKS 1322 if (PMC_PROC_IS_USING_PMCS(td->td_proc)) 1323 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_IN); 1324 #endif 1325 } 1326 1327 sched_lock.mtx_lock = (uintptr_t)td; 1328 td->td_oncpu = PCPU_GET(cpuid); 1329 } 1330 1331 void 1332 sched_wakeup(struct thread *td) 1333 { 1334 #ifdef KSE 1335 struct ksegrp *kg; 1336 #endif 1337 1338 mtx_assert(&sched_lock, MA_OWNED); 1339 #ifdef KSE 1340 kg = td->td_ksegrp; 1341 if (kg->kg_slptime > 1) { 1342 updatepri(kg); 1343 resetpriority(kg); 1344 } 1345 kg->kg_slptime = 0; 1346 #else 1347 if (td->td_slptime > 1) { 1348 updatepri(td); 1349 resetpriority(td); 1350 } 1351 td->td_slptime = 0; 1352 #endif 1353 setrunqueue(td, SRQ_BORING); 1354 } 1355 1356 #ifdef SMP 1357 /* enable HTT_2 if you have a 2-way HTT cpu.*/ 1358 static int 1359 forward_wakeup(int cpunum) 1360 { 1361 cpumask_t map, me, dontuse; 1362 cpumask_t map2; 1363 struct pcpu *pc; 1364 cpumask_t id, map3; 1365 1366 mtx_assert(&sched_lock, MA_OWNED); 1367 1368 CTR0(KTR_RUNQ, "forward_wakeup()"); 1369 1370 if ((!forward_wakeup_enabled) || 1371 (forward_wakeup_use_mask == 0 && forward_wakeup_use_loop == 0)) 1372 return (0); 1373 if (!smp_started || cold || panicstr) 1374 return (0); 1375 1376 forward_wakeups_requested++; 1377 1378 /* 1379 * check the idle mask we received against what we calculated before 1380 * in the old version. 1381 */ 1382 me = PCPU_GET(cpumask); 1383 /* 1384 * don't bother if we should be doing it ourself.. 1385 */ 1386 if ((me & idle_cpus_mask) && (cpunum == NOCPU || me == (1 << cpunum))) 1387 return (0); 1388 1389 dontuse = me | stopped_cpus | hlt_cpus_mask; 1390 map3 = 0; 1391 if (forward_wakeup_use_loop) { 1392 SLIST_FOREACH(pc, &cpuhead, pc_allcpu) { 1393 id = pc->pc_cpumask; 1394 if ( (id & dontuse) == 0 && 1395 pc->pc_curthread == pc->pc_idlethread) { 1396 map3 |= id; 1397 } 1398 } 1399 } 1400 1401 if (forward_wakeup_use_mask) { 1402 map = 0; 1403 map = idle_cpus_mask & ~dontuse; 1404 1405 /* If they are both on, compare and use loop if different */ 1406 if (forward_wakeup_use_loop) { 1407 if (map != map3) { 1408 printf("map (%02X) != map3 (%02X)\n", 1409 map, map3); 1410 map = map3; 1411 } 1412 } 1413 } else { 1414 map = map3; 1415 } 1416 /* If we only allow a specific CPU, then mask off all the others */ 1417 if (cpunum != NOCPU) { 1418 KASSERT((cpunum <= mp_maxcpus),("forward_wakeup: bad cpunum.")); 1419 map &= (1 << cpunum); 1420 } else { 1421 /* Try choose an idle die. */ 1422 if (forward_wakeup_use_htt) { 1423 map2 = (map & (map >> 1)) & 0x5555; 1424 if (map2) { 1425 map = map2; 1426 } 1427 } 1428 1429 /* set only one bit */ 1430 if (forward_wakeup_use_single) { 1431 map = map & ((~map) + 1); 1432 } 1433 } 1434 if (map) { 1435 forward_wakeups_delivered++; 1436 ipi_selected(map, IPI_AST); 1437 return (1); 1438 } 1439 if (cpunum == NOCPU) 1440 printf("forward_wakeup: Idle processor not found\n"); 1441 return (0); 1442 } 1443 #endif 1444 1445 #ifdef SMP 1446 static void kick_other_cpu(int pri,int cpuid); 1447 1448 static void 1449 kick_other_cpu(int pri,int cpuid) 1450 { 1451 struct pcpu * pcpu = pcpu_find(cpuid); 1452 int cpri = pcpu->pc_curthread->td_priority; 1453 1454 if (idle_cpus_mask & pcpu->pc_cpumask) { 1455 forward_wakeups_delivered++; 1456 ipi_selected(pcpu->pc_cpumask, IPI_AST); 1457 return; 1458 } 1459 1460 if (pri >= cpri) 1461 return; 1462 1463 #if defined(IPI_PREEMPTION) && defined(PREEMPTION) 1464 #if !defined(FULL_PREEMPTION) 1465 if (pri <= PRI_MAX_ITHD) 1466 #endif /* ! FULL_PREEMPTION */ 1467 { 1468 ipi_selected(pcpu->pc_cpumask, IPI_PREEMPT); 1469 return; 1470 } 1471 #endif /* defined(IPI_PREEMPTION) && defined(PREEMPTION) */ 1472 1473 pcpu->pc_curthread->td_flags |= TDF_NEEDRESCHED; 1474 ipi_selected( pcpu->pc_cpumask , IPI_AST); 1475 return; 1476 } 1477 #endif /* SMP */ 1478 1479 void 1480 sched_add(struct thread *td, int flags) 1481 #ifdef SMP 1482 { 1483 struct kse *ke; 1484 int forwarded = 0; 1485 int cpu; 1486 int single_cpu = 0; 1487 1488 ke = td->td_kse; 1489 mtx_assert(&sched_lock, MA_OWNED); 1490 KASSERT(ke->ke_state != KES_ONRUNQ, 1491 ("sched_add: kse %p (%s) already in run queue", ke, 1492 #ifdef KSE 1493 ke->ke_proc->p_comm)); 1494 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1495 #else 1496 td->td_proc->p_comm)); 1497 KASSERT(td->td_proc->p_sflag & PS_INMEM, 1498 #endif 1499 ("sched_add: process swapped out")); 1500 CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)", 1501 td, td->td_proc->p_comm, td->td_priority, curthread, 1502 curthread->td_proc->p_comm); 1503 1504 1505 if (td->td_pinned != 0) { 1506 cpu = td->td_lastcpu; 1507 ke->ke_runq = &runq_pcpu[cpu]; 1508 single_cpu = 1; 1509 CTR3(KTR_RUNQ, 1510 "sched_add: Put kse:%p(td:%p) on cpu%d runq", ke, td, cpu); 1511 } else if ((ke)->ke_flags & KEF_BOUND) { 1512 /* Find CPU from bound runq */ 1513 KASSERT(SKE_RUNQ_PCPU(ke),("sched_add: bound kse not on cpu runq")); 1514 cpu = ke->ke_runq - &runq_pcpu[0]; 1515 single_cpu = 1; 1516 CTR3(KTR_RUNQ, 1517 "sched_add: Put kse:%p(td:%p) on cpu%d runq", ke, td, cpu); 1518 } else { 1519 CTR2(KTR_RUNQ, 1520 "sched_add: adding kse:%p (td:%p) to gbl runq", ke, td); 1521 cpu = NOCPU; 1522 ke->ke_runq = &runq; 1523 } 1524 1525 if (single_cpu && (cpu != PCPU_GET(cpuid))) { 1526 kick_other_cpu(td->td_priority,cpu); 1527 } else { 1528 1529 if (!single_cpu) { 1530 cpumask_t me = PCPU_GET(cpumask); 1531 int idle = idle_cpus_mask & me; 1532 1533 if (!idle && ((flags & SRQ_INTR) == 0) && 1534 (idle_cpus_mask & ~(hlt_cpus_mask | me))) 1535 forwarded = forward_wakeup(cpu); 1536 } 1537 1538 if (!forwarded) { 1539 if ((flags & SRQ_YIELDING) == 0 && maybe_preempt(td)) 1540 return; 1541 else 1542 maybe_resched(td); 1543 } 1544 } 1545 1546 if ((td->td_proc->p_flag & P_NOLOAD) == 0) 1547 sched_load_add(); 1548 #ifdef KSE 1549 SLOT_USE(td->td_ksegrp); 1550 #endif 1551 runq_add(ke->ke_runq, ke, flags); 1552 ke->ke_state = KES_ONRUNQ; 1553 } 1554 #else /* SMP */ 1555 { 1556 struct kse *ke; 1557 ke = td->td_kse; 1558 mtx_assert(&sched_lock, MA_OWNED); 1559 KASSERT(ke->ke_state != KES_ONRUNQ, 1560 ("sched_add: kse %p (%s) already in run queue", ke, 1561 #ifdef KSE 1562 ke->ke_proc->p_comm)); 1563 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1564 #else 1565 td->td_proc->p_comm)); 1566 KASSERT(td->td_proc->p_sflag & PS_INMEM, 1567 #endif 1568 ("sched_add: process swapped out")); 1569 CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)", 1570 td, td->td_proc->p_comm, td->td_priority, curthread, 1571 curthread->td_proc->p_comm); 1572 CTR2(KTR_RUNQ, "sched_add: adding kse:%p (td:%p) to runq", ke, td); 1573 ke->ke_runq = &runq; 1574 1575 /* 1576 * If we are yielding (on the way out anyhow) 1577 * or the thread being saved is US, 1578 * then don't try be smart about preemption 1579 * or kicking off another CPU 1580 * as it won't help and may hinder. 1581 * In the YIEDLING case, we are about to run whoever is 1582 * being put in the queue anyhow, and in the 1583 * OURSELF case, we are puting ourself on the run queue 1584 * which also only happens when we are about to yield. 1585 */ 1586 if((flags & SRQ_YIELDING) == 0) { 1587 if (maybe_preempt(td)) 1588 return; 1589 } 1590 if ((td->td_proc->p_flag & P_NOLOAD) == 0) 1591 sched_load_add(); 1592 #ifdef KSE 1593 SLOT_USE(td->td_ksegrp); 1594 #endif 1595 runq_add(ke->ke_runq, ke, flags); 1596 ke->ke_state = KES_ONRUNQ; 1597 maybe_resched(td); 1598 } 1599 #endif /* SMP */ 1600 1601 void 1602 sched_rem(struct thread *td) 1603 { 1604 struct kse *ke; 1605 1606 ke = td->td_kse; 1607 #ifdef KSE 1608 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1609 #else 1610 KASSERT(td->td_proc->p_sflag & PS_INMEM, 1611 #endif 1612 ("sched_rem: process swapped out")); 1613 KASSERT((ke->ke_state == KES_ONRUNQ), 1614 ("sched_rem: KSE not on run queue")); 1615 mtx_assert(&sched_lock, MA_OWNED); 1616 CTR5(KTR_SCHED, "sched_rem: %p(%s) prio %d by %p(%s)", 1617 td, td->td_proc->p_comm, td->td_priority, curthread, 1618 curthread->td_proc->p_comm); 1619 1620 if ((td->td_proc->p_flag & P_NOLOAD) == 0) 1621 sched_load_rem(); 1622 #ifdef KSE 1623 SLOT_RELEASE(td->td_ksegrp); 1624 #endif 1625 runq_remove(ke->ke_runq, ke); 1626 1627 ke->ke_state = KES_THREAD; 1628 } 1629 1630 /* 1631 * Select threads to run. 1632 * Notice that the running threads still consume a slot. 1633 */ 1634 #ifdef KSE 1635 struct kse * 1636 #else 1637 struct thread * 1638 #endif 1639 sched_choose(void) 1640 { 1641 struct kse *ke; 1642 struct runq *rq; 1643 1644 #ifdef SMP 1645 struct kse *kecpu; 1646 1647 rq = &runq; 1648 ke = runq_choose(&runq); 1649 kecpu = runq_choose(&runq_pcpu[PCPU_GET(cpuid)]); 1650 1651 if (ke == NULL || 1652 (kecpu != NULL && 1653 kecpu->ke_thread->td_priority < ke->ke_thread->td_priority)) { 1654 CTR2(KTR_RUNQ, "choosing kse %p from pcpu runq %d", kecpu, 1655 PCPU_GET(cpuid)); 1656 ke = kecpu; 1657 rq = &runq_pcpu[PCPU_GET(cpuid)]; 1658 } else { 1659 CTR1(KTR_RUNQ, "choosing kse %p from main runq", ke); 1660 } 1661 1662 #else 1663 rq = &runq; 1664 ke = runq_choose(&runq); 1665 #endif 1666 1667 #ifdef KSE 1668 if (ke != NULL) { 1669 #else 1670 if (ke) { 1671 #endif 1672 runq_remove(rq, ke); 1673 ke->ke_state = KES_THREAD; 1674 1675 #ifdef KSE 1676 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1677 ("sched_choose: process swapped out")); 1678 #else 1679 KASSERT(ke->ke_thread->td_proc->p_sflag & PS_INMEM, 1680 ("sched_choose: process swapped out")); 1681 return (ke->ke_thread); 1682 #endif 1683 } 1684 #ifdef KSE 1685 return (ke); 1686 #else 1687 return (NULL); 1688 #endif 1689 } 1690 1691 void 1692 sched_userret(struct thread *td) 1693 { 1694 #ifdef KSE 1695 struct ksegrp *kg; 1696 #endif 1697 /* 1698 * XXX we cheat slightly on the locking here to avoid locking in 1699 * the usual case. Setting td_priority here is essentially an 1700 * incomplete workaround for not setting it properly elsewhere. 1701 * Now that some interrupt handlers are threads, not setting it 1702 * properly elsewhere can clobber it in the window between setting 1703 * it here and returning to user mode, so don't waste time setting 1704 * it perfectly here. 1705 */ 1706 KASSERT((td->td_flags & TDF_BORROWING) == 0, 1707 ("thread with borrowed priority returning to userland")); 1708 #ifdef KSE 1709 kg = td->td_ksegrp; 1710 if (td->td_priority != kg->kg_user_pri) { 1711 mtx_lock_spin(&sched_lock); 1712 td->td_priority = kg->kg_user_pri; 1713 td->td_base_pri = kg->kg_user_pri; 1714 mtx_unlock_spin(&sched_lock); 1715 } 1716 #else 1717 if (td->td_priority != td->td_user_pri) { 1718 mtx_lock_spin(&sched_lock); 1719 td->td_priority = td->td_user_pri; 1720 td->td_base_pri = td->td_user_pri; 1721 mtx_unlock_spin(&sched_lock); 1722 } 1723 #endif 1724 } 1725 1726 void 1727 sched_bind(struct thread *td, int cpu) 1728 { 1729 struct kse *ke; 1730 1731 mtx_assert(&sched_lock, MA_OWNED); 1732 KASSERT(TD_IS_RUNNING(td), 1733 ("sched_bind: cannot bind non-running thread")); 1734 1735 ke = td->td_kse; 1736 1737 ke->ke_flags |= KEF_BOUND; 1738 #ifdef SMP 1739 ke->ke_runq = &runq_pcpu[cpu]; 1740 if (PCPU_GET(cpuid) == cpu) 1741 return; 1742 1743 ke->ke_state = KES_THREAD; 1744 1745 mi_switch(SW_VOL, NULL); 1746 #endif 1747 } 1748 1749 void 1750 sched_unbind(struct thread* td) 1751 { 1752 mtx_assert(&sched_lock, MA_OWNED); 1753 td->td_kse->ke_flags &= ~KEF_BOUND; 1754 } 1755 1756 int 1757 sched_is_bound(struct thread *td) 1758 { 1759 mtx_assert(&sched_lock, MA_OWNED); 1760 return (td->td_kse->ke_flags & KEF_BOUND); 1761 } 1762 1763 void 1764 sched_relinquish(struct thread *td) 1765 { 1766 #ifdef KSE 1767 struct ksegrp *kg; 1768 1769 kg = td->td_ksegrp; 1770 #endif 1771 mtx_lock_spin(&sched_lock); 1772 #ifdef KSE 1773 if (kg->kg_pri_class == PRI_TIMESHARE) 1774 #else 1775 if (td->td_pri_class == PRI_TIMESHARE) 1776 #endif 1777 sched_prio(td, PRI_MAX_TIMESHARE); 1778 mi_switch(SW_VOL, NULL); 1779 mtx_unlock_spin(&sched_lock); 1780 } 1781 1782 int 1783 sched_load(void) 1784 { 1785 return (sched_tdcnt); 1786 } 1787 1788 #ifdef KSE 1789 int 1790 sched_sizeof_ksegrp(void) 1791 { 1792 return (sizeof(struct ksegrp) + sizeof(struct kg_sched)); 1793 } 1794 #endif 1795 1796 int 1797 sched_sizeof_proc(void) 1798 { 1799 return (sizeof(struct proc)); 1800 } 1801 1802 int 1803 sched_sizeof_thread(void) 1804 { 1805 return (sizeof(struct thread) + sizeof(struct kse)); 1806 } 1807 1808 fixpt_t 1809 sched_pctcpu(struct thread *td) 1810 { 1811 struct kse *ke; 1812 1813 ke = td->td_kse; 1814 return (ke->ke_pctcpu); 1815 } 1816 1817 void 1818 sched_tick(void) 1819 { 1820 } 1821 #define KERN_SWITCH_INCLUDE 1 1822 #include "kern/kern_switch.c" 1823