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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 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/mutex.h> 48 #include <sys/proc.h> 49 #include <sys/resourcevar.h> 50 #include <sys/sched.h> 51 #include <sys/smp.h> 52 #include <sys/sysctl.h> 53 #include <sys/sx.h> 54 55 /* 56 * INVERSE_ESTCPU_WEIGHT is only suitable for statclock() frequencies in 57 * the range 100-256 Hz (approximately). 58 */ 59 #define ESTCPULIM(e) \ 60 min((e), INVERSE_ESTCPU_WEIGHT * (NICE_WEIGHT * (PRIO_MAX - PRIO_MIN) - \ 61 RQ_PPQ) + INVERSE_ESTCPU_WEIGHT - 1) 62 #define INVERSE_ESTCPU_WEIGHT 8 /* 1 / (priorities per estcpu level). */ 63 #define NICE_WEIGHT 1 /* Priorities per nice level. */ 64 65 struct ke_sched { 66 int ske_cpticks; /* (j) Ticks of cpu time. */ 67 }; 68 69 static struct ke_sched ke_sched; 70 71 struct ke_sched *kse0_sched = &ke_sched; 72 struct kg_sched *ksegrp0_sched = NULL; 73 struct p_sched *proc0_sched = NULL; 74 struct td_sched *thread0_sched = NULL; 75 76 static int sched_quantum; /* Roundrobin scheduling quantum in ticks. */ 77 #define SCHED_QUANTUM (hz / 10) /* Default sched quantum */ 78 79 static struct callout schedcpu_callout; 80 static struct callout roundrobin_callout; 81 82 static void roundrobin(void *arg); 83 static void schedcpu(void *arg); 84 static void sched_setup(void *dummy); 85 static void maybe_resched(struct thread *td); 86 static void updatepri(struct ksegrp *kg); 87 static void resetpriority(struct ksegrp *kg); 88 89 SYSINIT(sched_setup, SI_SUB_KICK_SCHEDULER, SI_ORDER_FIRST, sched_setup, NULL) 90 91 /* 92 * Global run queue. 93 */ 94 static struct runq runq; 95 SYSINIT(runq, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, runq_init, &runq) 96 97 static int 98 sysctl_kern_quantum(SYSCTL_HANDLER_ARGS) 99 { 100 int error, new_val; 101 102 new_val = sched_quantum * tick; 103 error = sysctl_handle_int(oidp, &new_val, 0, req); 104 if (error != 0 || req->newptr == NULL) 105 return (error); 106 if (new_val < tick) 107 return (EINVAL); 108 sched_quantum = new_val / tick; 109 hogticks = 2 * sched_quantum; 110 return (0); 111 } 112 113 SYSCTL_PROC(_kern, OID_AUTO, quantum, CTLTYPE_INT|CTLFLAG_RW, 114 0, sizeof sched_quantum, sysctl_kern_quantum, "I", 115 "Roundrobin scheduling quantum in microseconds"); 116 117 /* 118 * Arrange to reschedule if necessary, taking the priorities and 119 * schedulers into account. 120 */ 121 static void 122 maybe_resched(struct thread *td) 123 { 124 125 mtx_assert(&sched_lock, MA_OWNED); 126 if (td->td_priority < curthread->td_priority && curthread->td_kse) 127 curthread->td_flags |= TDF_NEEDRESCHED; 128 } 129 130 /* 131 * Force switch among equal priority processes every 100ms. 132 * We don't actually need to force a context switch of the current process. 133 * The act of firing the event triggers a context switch to softclock() and 134 * then switching back out again which is equivalent to a preemption, thus 135 * no further work is needed on the local CPU. 136 */ 137 /* ARGSUSED */ 138 static void 139 roundrobin(void *arg) 140 { 141 142 #ifdef SMP 143 mtx_lock_spin(&sched_lock); 144 forward_roundrobin(); 145 mtx_unlock_spin(&sched_lock); 146 #endif 147 148 callout_reset(&roundrobin_callout, sched_quantum, roundrobin, NULL); 149 } 150 151 /* 152 * Constants for digital decay and forget: 153 * 90% of (kg_estcpu) usage in 5 * loadav time 154 * 95% of (ke_pctcpu) usage in 60 seconds (load insensitive) 155 * Note that, as ps(1) mentions, this can let percentages 156 * total over 100% (I've seen 137.9% for 3 processes). 157 * 158 * Note that schedclock() updates kg_estcpu and p_cpticks asynchronously. 159 * 160 * We wish to decay away 90% of kg_estcpu in (5 * loadavg) seconds. 161 * That is, the system wants to compute a value of decay such 162 * that the following for loop: 163 * for (i = 0; i < (5 * loadavg); i++) 164 * kg_estcpu *= decay; 165 * will compute 166 * kg_estcpu *= 0.1; 167 * for all values of loadavg: 168 * 169 * Mathematically this loop can be expressed by saying: 170 * decay ** (5 * loadavg) ~= .1 171 * 172 * The system computes decay as: 173 * decay = (2 * loadavg) / (2 * loadavg + 1) 174 * 175 * We wish to prove that the system's computation of decay 176 * will always fulfill the equation: 177 * decay ** (5 * loadavg) ~= .1 178 * 179 * If we compute b as: 180 * b = 2 * loadavg 181 * then 182 * decay = b / (b + 1) 183 * 184 * We now need to prove two things: 185 * 1) Given factor ** (5 * loadavg) ~= .1, prove factor == b/(b+1) 186 * 2) Given b/(b+1) ** power ~= .1, prove power == (5 * loadavg) 187 * 188 * Facts: 189 * For x close to zero, exp(x) =~ 1 + x, since 190 * exp(x) = 0! + x**1/1! + x**2/2! + ... . 191 * therefore exp(-1/b) =~ 1 - (1/b) = (b-1)/b. 192 * For x close to zero, ln(1+x) =~ x, since 193 * ln(1+x) = x - x**2/2 + x**3/3 - ... -1 < x < 1 194 * therefore ln(b/(b+1)) = ln(1 - 1/(b+1)) =~ -1/(b+1). 195 * ln(.1) =~ -2.30 196 * 197 * Proof of (1): 198 * Solve (factor)**(power) =~ .1 given power (5*loadav): 199 * solving for factor, 200 * ln(factor) =~ (-2.30/5*loadav), or 201 * factor =~ exp(-1/((5/2.30)*loadav)) =~ exp(-1/(2*loadav)) = 202 * exp(-1/b) =~ (b-1)/b =~ b/(b+1). QED 203 * 204 * Proof of (2): 205 * Solve (factor)**(power) =~ .1 given factor == (b/(b+1)): 206 * solving for power, 207 * power*ln(b/(b+1)) =~ -2.30, or 208 * power =~ 2.3 * (b + 1) = 4.6*loadav + 2.3 =~ 5*loadav. QED 209 * 210 * Actual power values for the implemented algorithm are as follows: 211 * loadav: 1 2 3 4 212 * power: 5.68 10.32 14.94 19.55 213 */ 214 215 /* calculations for digital decay to forget 90% of usage in 5*loadav sec */ 216 #define loadfactor(loadav) (2 * (loadav)) 217 #define decay_cpu(loadfac, cpu) (((loadfac) * (cpu)) / ((loadfac) + FSCALE)) 218 219 /* decay 95% of `ke_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */ 220 static fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */ 221 SYSCTL_INT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, ""); 222 223 /* 224 * If `ccpu' is not equal to `exp(-1/20)' and you still want to use the 225 * faster/more-accurate formula, you'll have to estimate CCPU_SHIFT below 226 * and possibly adjust FSHIFT in "param.h" so that (FSHIFT >= CCPU_SHIFT). 227 * 228 * To estimate CCPU_SHIFT for exp(-1/20), the following formula was used: 229 * 1 - exp(-1/20) ~= 0.0487 ~= 0.0488 == 1 (fixed pt, *11* bits). 230 * 231 * If you don't want to bother with the faster/more-accurate formula, you 232 * can set CCPU_SHIFT to (FSHIFT + 1) which will use a slower/less-accurate 233 * (more general) method of calculating the %age of CPU used by a process. 234 */ 235 #define CCPU_SHIFT 11 236 237 /* 238 * Recompute process priorities, every hz ticks. 239 * MP-safe, called without the Giant mutex. 240 */ 241 /* ARGSUSED */ 242 static void 243 schedcpu(void *arg) 244 { 245 register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]); 246 struct thread *td; 247 struct proc *p; 248 struct kse *ke; 249 struct ksegrp *kg; 250 int awake, realstathz; 251 252 realstathz = stathz ? stathz : hz; 253 sx_slock(&allproc_lock); 254 FOREACH_PROC_IN_SYSTEM(p) { 255 /* 256 * Prevent state changes and protect run queue. 257 */ 258 mtx_lock_spin(&sched_lock); 259 /* 260 * Increment time in/out of memory. We ignore overflow; with 261 * 16-bit int's (remember them?) overflow takes 45 days. 262 */ 263 p->p_swtime++; 264 FOREACH_KSEGRP_IN_PROC(p, kg) { 265 awake = 0; 266 FOREACH_KSE_IN_GROUP(kg, ke) { 267 /* 268 * Increment sleep time (if sleeping). We 269 * ignore overflow, as above. 270 */ 271 /* 272 * The kse slptimes are not touched in wakeup 273 * because the thread may not HAVE a KSE. 274 */ 275 if (ke->ke_state == KES_ONRUNQ) { 276 awake = 1; 277 ke->ke_flags &= ~KEF_DIDRUN; 278 } else if ((ke->ke_state == KES_THREAD) && 279 (TD_IS_RUNNING(ke->ke_thread))) { 280 awake = 1; 281 /* Do not clear KEF_DIDRUN */ 282 } else if (ke->ke_flags & KEF_DIDRUN) { 283 awake = 1; 284 ke->ke_flags &= ~KEF_DIDRUN; 285 } 286 287 /* 288 * ke_pctcpu is only for ps and ttyinfo(). 289 * Do it per kse, and add them up at the end? 290 * XXXKSE 291 */ 292 ke->ke_pctcpu = (ke->ke_pctcpu * ccpu) >> 293 FSHIFT; 294 /* 295 * If the kse has been idle the entire second, 296 * stop recalculating its priority until 297 * it wakes up. 298 */ 299 if (ke->ke_sched->ske_cpticks == 0) 300 continue; 301 #if (FSHIFT >= CCPU_SHIFT) 302 ke->ke_pctcpu += (realstathz == 100) 303 ? ((fixpt_t) ke->ke_sched->ske_cpticks) << 304 (FSHIFT - CCPU_SHIFT) : 305 100 * (((fixpt_t) ke->ke_sched->ske_cpticks) 306 << (FSHIFT - CCPU_SHIFT)) / realstathz; 307 #else 308 ke->ke_pctcpu += ((FSCALE - ccpu) * 309 (ke->ke_sched->ske_cpticks * 310 FSCALE / realstathz)) >> FSHIFT; 311 #endif 312 ke->ke_sched->ske_cpticks = 0; 313 } /* end of kse loop */ 314 /* 315 * If there are ANY running threads in this KSEGRP, 316 * then don't count it as sleeping. 317 */ 318 if (awake) { 319 if (kg->kg_slptime > 1) { 320 /* 321 * In an ideal world, this should not 322 * happen, because whoever woke us 323 * up from the long sleep should have 324 * unwound the slptime and reset our 325 * priority before we run at the stale 326 * priority. Should KASSERT at some 327 * point when all the cases are fixed. 328 */ 329 updatepri(kg); 330 } 331 kg->kg_slptime = 0; 332 } else 333 kg->kg_slptime++; 334 if (kg->kg_slptime > 1) 335 continue; 336 kg->kg_estcpu = decay_cpu(loadfac, kg->kg_estcpu); 337 resetpriority(kg); 338 FOREACH_THREAD_IN_GROUP(kg, td) { 339 if (td->td_priority >= PUSER) { 340 sched_prio(td, kg->kg_user_pri); 341 } 342 } 343 } /* end of ksegrp loop */ 344 mtx_unlock_spin(&sched_lock); 345 } /* end of process loop */ 346 sx_sunlock(&allproc_lock); 347 callout_reset(&schedcpu_callout, hz, schedcpu, NULL); 348 } 349 350 /* 351 * Recalculate the priority of a process after it has slept for a while. 352 * For all load averages >= 1 and max kg_estcpu of 255, sleeping for at 353 * least six times the loadfactor will decay kg_estcpu to zero. 354 */ 355 static void 356 updatepri(struct ksegrp *kg) 357 { 358 register fixpt_t loadfac; 359 register unsigned int newcpu; 360 361 loadfac = loadfactor(averunnable.ldavg[0]); 362 if (kg->kg_slptime > 5 * loadfac) 363 kg->kg_estcpu = 0; 364 else { 365 newcpu = kg->kg_estcpu; 366 kg->kg_slptime--; /* was incremented in schedcpu() */ 367 while (newcpu && --kg->kg_slptime) 368 newcpu = decay_cpu(loadfac, newcpu); 369 kg->kg_estcpu = newcpu; 370 } 371 resetpriority(kg); 372 } 373 374 /* 375 * Compute the priority of a process when running in user mode. 376 * Arrange to reschedule if the resulting priority is better 377 * than that of the current process. 378 */ 379 static void 380 resetpriority(struct ksegrp *kg) 381 { 382 register unsigned int newpriority; 383 struct thread *td; 384 385 if (kg->kg_pri_class == PRI_TIMESHARE) { 386 newpriority = PUSER + kg->kg_estcpu / INVERSE_ESTCPU_WEIGHT + 387 NICE_WEIGHT * (kg->kg_nice - PRIO_MIN); 388 newpriority = min(max(newpriority, PRI_MIN_TIMESHARE), 389 PRI_MAX_TIMESHARE); 390 kg->kg_user_pri = newpriority; 391 } 392 FOREACH_THREAD_IN_GROUP(kg, td) { 393 maybe_resched(td); /* XXXKSE silly */ 394 } 395 } 396 397 /* ARGSUSED */ 398 static void 399 sched_setup(void *dummy) 400 { 401 402 if (sched_quantum == 0) 403 sched_quantum = SCHED_QUANTUM; 404 hogticks = 2 * sched_quantum; 405 406 callout_init(&schedcpu_callout, CALLOUT_MPSAFE); 407 callout_init(&roundrobin_callout, 0); 408 409 /* Kick off timeout driven events by calling first time. */ 410 roundrobin(NULL); 411 schedcpu(NULL); 412 } 413 414 /* External interfaces start here */ 415 int 416 sched_runnable(void) 417 { 418 return runq_check(&runq); 419 } 420 421 int 422 sched_rr_interval(void) 423 { 424 if (sched_quantum == 0) 425 sched_quantum = SCHED_QUANTUM; 426 return (sched_quantum); 427 } 428 429 /* 430 * We adjust the priority of the current process. The priority of 431 * a process gets worse as it accumulates CPU time. The cpu usage 432 * estimator (kg_estcpu) is increased here. resetpriority() will 433 * compute a different priority each time kg_estcpu increases by 434 * INVERSE_ESTCPU_WEIGHT 435 * (until MAXPRI is reached). The cpu usage estimator ramps up 436 * quite quickly when the process is running (linearly), and decays 437 * away exponentially, at a rate which is proportionally slower when 438 * the system is busy. The basic principle is that the system will 439 * 90% forget that the process used a lot of CPU time in 5 * loadav 440 * seconds. This causes the system to favor processes which haven't 441 * run much recently, and to round-robin among other processes. 442 */ 443 void 444 sched_clock(struct kse *ke) 445 { 446 struct ksegrp *kg; 447 struct thread *td; 448 449 mtx_assert(&sched_lock, MA_OWNED); 450 kg = ke->ke_ksegrp; 451 td = ke->ke_thread; 452 453 ke->ke_sched->ske_cpticks++; 454 kg->kg_estcpu = ESTCPULIM(kg->kg_estcpu + 1); 455 if ((kg->kg_estcpu % INVERSE_ESTCPU_WEIGHT) == 0) { 456 resetpriority(kg); 457 if (td->td_priority >= PUSER) 458 td->td_priority = kg->kg_user_pri; 459 } 460 } 461 462 /* 463 * charge childs scheduling cpu usage to parent. 464 * 465 * XXXKSE assume only one thread & kse & ksegrp keep estcpu in each ksegrp. 466 * Charge it to the ksegrp that did the wait since process estcpu is sum of 467 * all ksegrps, this is strictly as expected. Assume that the child process 468 * aggregated all the estcpu into the 'built-in' ksegrp. 469 */ 470 void 471 sched_exit(struct proc *p, struct proc *p1) 472 { 473 sched_exit_kse(FIRST_KSE_IN_PROC(p), FIRST_KSE_IN_PROC(p1)); 474 sched_exit_ksegrp(FIRST_KSEGRP_IN_PROC(p), FIRST_KSEGRP_IN_PROC(p1)); 475 sched_exit_thread(FIRST_THREAD_IN_PROC(p), FIRST_THREAD_IN_PROC(p1)); 476 } 477 478 void 479 sched_exit_kse(struct kse *ke, struct kse *child) 480 { 481 } 482 483 void 484 sched_exit_ksegrp(struct ksegrp *kg, struct ksegrp *child) 485 { 486 487 mtx_assert(&sched_lock, MA_OWNED); 488 kg->kg_estcpu = ESTCPULIM(kg->kg_estcpu + child->kg_estcpu); 489 } 490 491 void 492 sched_exit_thread(struct thread *td, struct thread *child) 493 { 494 } 495 496 void 497 sched_fork(struct proc *p, struct proc *p1) 498 { 499 sched_fork_kse(FIRST_KSE_IN_PROC(p), FIRST_KSE_IN_PROC(p1)); 500 sched_fork_ksegrp(FIRST_KSEGRP_IN_PROC(p), FIRST_KSEGRP_IN_PROC(p1)); 501 sched_fork_thread(FIRST_THREAD_IN_PROC(p), FIRST_THREAD_IN_PROC(p1)); 502 } 503 504 void 505 sched_fork_kse(struct kse *ke, struct kse *child) 506 { 507 child->ke_sched->ske_cpticks = 0; 508 } 509 510 void 511 sched_fork_ksegrp(struct ksegrp *kg, struct ksegrp *child) 512 { 513 mtx_assert(&sched_lock, MA_OWNED); 514 child->kg_estcpu = kg->kg_estcpu; 515 } 516 517 void 518 sched_fork_thread(struct thread *td, struct thread *child) 519 { 520 } 521 522 void 523 sched_nice(struct ksegrp *kg, int nice) 524 { 525 526 PROC_LOCK_ASSERT(kg->kg_proc, MA_OWNED); 527 mtx_assert(&sched_lock, MA_OWNED); 528 kg->kg_nice = nice; 529 resetpriority(kg); 530 } 531 532 void 533 sched_class(struct ksegrp *kg, int class) 534 { 535 mtx_assert(&sched_lock, MA_OWNED); 536 kg->kg_pri_class = class; 537 } 538 539 /* 540 * Adjust the priority of a thread. 541 * This may include moving the thread within the KSEGRP, 542 * changing the assignment of a kse to the thread, 543 * and moving a KSE in the system run queue. 544 */ 545 void 546 sched_prio(struct thread *td, u_char prio) 547 { 548 549 mtx_assert(&sched_lock, MA_OWNED); 550 if (TD_ON_RUNQ(td)) { 551 adjustrunqueue(td, prio); 552 } else { 553 td->td_priority = prio; 554 } 555 } 556 557 void 558 sched_sleep(struct thread *td, u_char prio) 559 { 560 561 mtx_assert(&sched_lock, MA_OWNED); 562 td->td_ksegrp->kg_slptime = 0; 563 td->td_priority = prio; 564 } 565 566 void 567 sched_switchin(struct thread *td) 568 { 569 570 mtx_assert(&sched_lock, MA_OWNED); 571 td->td_oncpu = PCPU_GET(cpuid); 572 } 573 574 void 575 sched_switchout(struct thread *td) 576 { 577 struct kse *ke; 578 struct proc *p; 579 580 ke = td->td_kse; 581 p = td->td_proc; 582 583 mtx_assert(&sched_lock, MA_OWNED); 584 KASSERT((ke->ke_state == KES_THREAD), ("mi_switch: kse state?")); 585 586 td->td_lastcpu = td->td_oncpu; 587 td->td_last_kse = ke; 588 td->td_oncpu = NOCPU; 589 td->td_flags &= ~TDF_NEEDRESCHED; 590 /* 591 * At the last moment, if this thread is still marked RUNNING, 592 * then put it back on the run queue as it has not been suspended 593 * or stopped or any thing else similar. 594 */ 595 if (TD_IS_RUNNING(td)) { 596 /* Put us back on the run queue (kse and all). */ 597 setrunqueue(td); 598 } else if (p->p_flag & P_SA) { 599 /* 600 * We will not be on the run queue. So we must be 601 * sleeping or similar. As it's available, 602 * someone else can use the KSE if they need it. 603 */ 604 kse_reassign(ke); 605 } 606 } 607 608 void 609 sched_wakeup(struct thread *td) 610 { 611 struct ksegrp *kg; 612 613 mtx_assert(&sched_lock, MA_OWNED); 614 kg = td->td_ksegrp; 615 if (kg->kg_slptime > 1) 616 updatepri(kg); 617 kg->kg_slptime = 0; 618 setrunqueue(td); 619 maybe_resched(td); 620 } 621 622 void 623 sched_add(struct kse *ke) 624 { 625 mtx_assert(&sched_lock, MA_OWNED); 626 KASSERT((ke->ke_thread != NULL), ("runq_add: No thread on KSE")); 627 KASSERT((ke->ke_thread->td_kse != NULL), 628 ("runq_add: No KSE on thread")); 629 KASSERT(ke->ke_state != KES_ONRUNQ, 630 ("runq_add: kse %p (%s) already in run queue", ke, 631 ke->ke_proc->p_comm)); 632 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 633 ("runq_add: process swapped out")); 634 ke->ke_ksegrp->kg_runq_kses++; 635 ke->ke_state = KES_ONRUNQ; 636 637 runq_add(&runq, ke); 638 } 639 640 void 641 sched_rem(struct kse *ke) 642 { 643 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 644 ("runq_remove: process swapped out")); 645 KASSERT((ke->ke_state == KES_ONRUNQ), ("KSE not on run queue")); 646 mtx_assert(&sched_lock, MA_OWNED); 647 648 runq_remove(&runq, ke); 649 ke->ke_state = KES_THREAD; 650 ke->ke_ksegrp->kg_runq_kses--; 651 } 652 653 struct kse * 654 sched_choose(void) 655 { 656 struct kse *ke; 657 658 ke = runq_choose(&runq); 659 660 if (ke != NULL) { 661 runq_remove(&runq, ke); 662 ke->ke_state = KES_THREAD; 663 664 KASSERT((ke->ke_thread != NULL), 665 ("runq_choose: No thread on KSE")); 666 KASSERT((ke->ke_thread->td_kse != NULL), 667 ("runq_choose: No KSE on thread")); 668 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 669 ("runq_choose: process swapped out")); 670 } 671 return (ke); 672 } 673 674 void 675 sched_userret(struct thread *td) 676 { 677 struct ksegrp *kg; 678 /* 679 * XXX we cheat slightly on the locking here to avoid locking in 680 * the usual case. Setting td_priority here is essentially an 681 * incomplete workaround for not setting it properly elsewhere. 682 * Now that some interrupt handlers are threads, not setting it 683 * properly elsewhere can clobber it in the window between setting 684 * it here and returning to user mode, so don't waste time setting 685 * it perfectly here. 686 */ 687 kg = td->td_ksegrp; 688 if (td->td_priority != kg->kg_user_pri) { 689 mtx_lock_spin(&sched_lock); 690 td->td_priority = kg->kg_user_pri; 691 mtx_unlock_spin(&sched_lock); 692 } 693 } 694 695 int 696 sched_sizeof_kse(void) 697 { 698 return (sizeof(struct kse) + sizeof(struct ke_sched)); 699 } 700 int 701 sched_sizeof_ksegrp(void) 702 { 703 return (sizeof(struct ksegrp)); 704 } 705 int 706 sched_sizeof_proc(void) 707 { 708 return (sizeof(struct proc)); 709 } 710 int 711 sched_sizeof_thread(void) 712 { 713 return (sizeof(struct thread)); 714 } 715 716 fixpt_t 717 sched_pctcpu(struct kse *ke) 718 { 719 return (ke->ke_pctcpu); 720 } 721