Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/kern/kern_switch.c
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1 /* 2 * Copyright (c) 2001 Jake Burkholder <jake@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: releng/5.1/sys/kern/kern_switch.c 115215 2003-05-21 18:53:25Z julian $ 27 */ 28 29 /*** 30 31 Here is the logic.. 32 33 If there are N processors, then there are at most N KSEs (kernel 34 schedulable entities) working to process threads that belong to a 35 KSEGOUP (kg). If there are X of these KSEs actually running at the 36 moment in question, then there are at most M (N-X) of these KSEs on 37 the run queue, as running KSEs are not on the queue. 38 39 Runnable threads are queued off the KSEGROUP in priority order. 40 If there are M or more threads runnable, the top M threads 41 (by priority) are 'preassigned' to the M KSEs not running. The KSEs take 42 their priority from those threads and are put on the run queue. 43 44 The last thread that had a priority high enough to have a KSE associated 45 with it, AND IS ON THE RUN QUEUE is pointed to by 46 kg->kg_last_assigned. If no threads queued off the KSEGROUP have KSEs 47 assigned as all the available KSEs are activly running, or because there 48 are no threads queued, that pointer is NULL. 49 50 When a KSE is removed from the run queue to become runnable, we know 51 it was associated with the highest priority thread in the queue (at the head 52 of the queue). If it is also the last assigned we know M was 1 and must 53 now be 0. Since the thread is no longer queued that pointer must be 54 removed from it. Since we know there were no more KSEs available, 55 (M was 1 and is now 0) and since we are not FREEING our KSE 56 but using it, we know there are STILL no more KSEs available, we can prove 57 that the next thread in the ksegrp list will not have a KSE to assign to 58 it, so we can show that the pointer must be made 'invalid' (NULL). 59 60 The pointer exists so that when a new thread is made runnable, it can 61 have its priority compared with the last assigned thread to see if 62 it should 'steal' its KSE or not.. i.e. is it 'earlier' 63 on the list than that thread or later.. If it's earlier, then the KSE is 64 removed from the last assigned (which is now not assigned a KSE) 65 and reassigned to the new thread, which is placed earlier in the list. 66 The pointer is then backed up to the previous thread (which may or may not 67 be the new thread). 68 69 When a thread sleeps or is removed, the KSE becomes available and if there 70 are queued threads that are not assigned KSEs, the highest priority one of 71 them is assigned the KSE, which is then placed back on the run queue at 72 the approipriate place, and the kg->kg_last_assigned pointer is adjusted down 73 to point to it. 74 75 The following diagram shows 2 KSEs and 3 threads from a single process. 76 77 RUNQ: --->KSE---KSE--... (KSEs queued at priorities from threads) 78 \ \____ 79 \ \ 80 KSEGROUP---thread--thread--thread (queued in priority order) 81 \ / 82 \_______________/ 83 (last_assigned) 84 85 The result of this scheme is that the M available KSEs are always 86 queued at the priorities they have inherrited from the M highest priority 87 threads for that KSEGROUP. If this situation changes, the KSEs are 88 reassigned to keep this true. 89 90 */ 91 92 #include <sys/param.h> 93 #include <sys/systm.h> 94 #include <sys/kernel.h> 95 #include <sys/ktr.h> 96 #include <sys/lock.h> 97 #include <sys/mutex.h> 98 #include <sys/proc.h> 99 #include <sys/queue.h> 100 #include <sys/sched.h> 101 #if defined(SMP) && defined(__i386__) 102 #include <sys/smp.h> 103 #endif 104 #include <machine/critical.h> 105 106 CTASSERT((RQB_BPW * RQB_LEN) == RQ_NQS); 107 108 void panc(char *string1, char *string2); 109 110 #if 0 111 static void runq_readjust(struct runq *rq, struct kse *ke); 112 #endif 113 /************************************************************************ 114 * Functions that manipulate runnability from a thread perspective. * 115 ************************************************************************/ 116 /* 117 * Select the KSE that will be run next. From that find the thread, and 118 * remove it from the KSEGRP's run queue. If there is thread clustering, 119 * this will be what does it. 120 */ 121 struct thread * 122 choosethread(void) 123 { 124 struct kse *ke; 125 struct thread *td; 126 struct ksegrp *kg; 127 128 #if defined(SMP) && defined(__i386__) 129 if (smp_active == 0 && PCPU_GET(cpuid) != 0) { 130 /* Shutting down, run idlethread on AP's */ 131 td = PCPU_GET(idlethread); 132 ke = td->td_kse; 133 CTR1(KTR_RUNQ, "choosethread: td=%p (idle)", td); 134 ke->ke_flags |= KEF_DIDRUN; 135 TD_SET_RUNNING(td); 136 return (td); 137 } 138 #endif 139 140 retry: 141 ke = sched_choose(); 142 if (ke) { 143 td = ke->ke_thread; 144 KASSERT((td->td_kse == ke), ("kse/thread mismatch")); 145 kg = ke->ke_ksegrp; 146 if (td->td_proc->p_flag & P_THREADED) { 147 if (kg->kg_last_assigned == td) { 148 kg->kg_last_assigned = TAILQ_PREV(td, 149 threadqueue, td_runq); 150 } 151 TAILQ_REMOVE(&kg->kg_runq, td, td_runq); 152 } 153 kg->kg_runnable--; 154 CTR2(KTR_RUNQ, "choosethread: td=%p pri=%d", 155 td, td->td_priority); 156 } else { 157 /* Simulate runq_choose() having returned the idle thread */ 158 td = PCPU_GET(idlethread); 159 ke = td->td_kse; 160 CTR1(KTR_RUNQ, "choosethread: td=%p (idle)", td); 161 } 162 ke->ke_flags |= KEF_DIDRUN; 163 164 /* 165 * If we are in panic, only allow system threads, 166 * plus the one we are running in, to be run. 167 */ 168 if (panicstr && ((td->td_proc->p_flag & P_SYSTEM) == 0 && 169 (td->td_flags & TDF_INPANIC) == 0)) { 170 /* note that it is no longer on the run queue */ 171 TD_SET_CAN_RUN(td); 172 goto retry; 173 } 174 175 TD_SET_RUNNING(td); 176 return (td); 177 } 178 179 /* 180 * Given a surplus KSE, either assign a new runable thread to it 181 * (and put it in the run queue) or put it in the ksegrp's idle KSE list. 182 * Assumes that the original thread is not runnable. 183 */ 184 void 185 kse_reassign(struct kse *ke) 186 { 187 struct ksegrp *kg; 188 struct thread *td; 189 struct thread *original; 190 191 mtx_assert(&sched_lock, MA_OWNED); 192 original = ke->ke_thread; 193 KASSERT(original == NULL || TD_IS_INHIBITED(original), 194 ("reassigning KSE with runnable thread")); 195 kg = ke->ke_ksegrp; 196 if (original) 197 original->td_kse = NULL; 198 199 /* 200 * Find the first unassigned thread 201 */ 202 if ((td = kg->kg_last_assigned) != NULL) 203 td = TAILQ_NEXT(td, td_runq); 204 else 205 td = TAILQ_FIRST(&kg->kg_runq); 206 207 /* 208 * If we found one, assign it the kse, otherwise idle the kse. 209 */ 210 if (td) { 211 kg->kg_last_assigned = td; 212 td->td_kse = ke; 213 ke->ke_thread = td; 214 sched_add(ke); 215 CTR2(KTR_RUNQ, "kse_reassign: ke%p -> td%p", ke, td); 216 return; 217 } 218 219 ke->ke_state = KES_IDLE; 220 ke->ke_thread = NULL; 221 TAILQ_INSERT_TAIL(&kg->kg_iq, ke, ke_kgrlist); 222 kg->kg_idle_kses++; 223 CTR1(KTR_RUNQ, "kse_reassign: ke%p on idle queue", ke); 224 return; 225 } 226 227 #if 0 228 /* 229 * Remove a thread from its KSEGRP's run queue. 230 * This in turn may remove it from a KSE if it was already assigned 231 * to one, possibly causing a new thread to be assigned to the KSE 232 * and the KSE getting a new priority. 233 */ 234 static void 235 remrunqueue(struct thread *td) 236 { 237 struct thread *td2, *td3; 238 struct ksegrp *kg; 239 struct kse *ke; 240 241 mtx_assert(&sched_lock, MA_OWNED); 242 KASSERT((TD_ON_RUNQ(td)), ("remrunqueue: Bad state on run queue")); 243 kg = td->td_ksegrp; 244 ke = td->td_kse; 245 CTR1(KTR_RUNQ, "remrunqueue: td%p", td); 246 kg->kg_runnable--; 247 TD_SET_CAN_RUN(td); 248 /* 249 * If it is not a threaded process, take the shortcut. 250 */ 251 if ((td->td_proc->p_flag & P_THREADED) == 0) { 252 /* Bring its kse with it, leave the thread attached */ 253 sched_rem(ke); 254 ke->ke_state = KES_THREAD; 255 return; 256 } 257 td3 = TAILQ_PREV(td, threadqueue, td_runq); 258 TAILQ_REMOVE(&kg->kg_runq, td, td_runq); 259 if (ke) { 260 /* 261 * This thread has been assigned to a KSE. 262 * We need to dissociate it and try assign the 263 * KSE to the next available thread. Then, we should 264 * see if we need to move the KSE in the run queues. 265 */ 266 sched_rem(ke); 267 ke->ke_state = KES_THREAD; 268 td2 = kg->kg_last_assigned; 269 KASSERT((td2 != NULL), ("last assigned has wrong value")); 270 if (td2 == td) 271 kg->kg_last_assigned = td3; 272 kse_reassign(ke); 273 } 274 } 275 #endif 276 277 /* 278 * Change the priority of a thread that is on the run queue. 279 */ 280 void 281 adjustrunqueue( struct thread *td, int newpri) 282 { 283 struct ksegrp *kg; 284 struct kse *ke; 285 286 mtx_assert(&sched_lock, MA_OWNED); 287 KASSERT((TD_ON_RUNQ(td)), ("adjustrunqueue: Bad state on run queue")); 288 289 ke = td->td_kse; 290 CTR1(KTR_RUNQ, "adjustrunqueue: td%p", td); 291 /* 292 * If it is not a threaded process, take the shortcut. 293 */ 294 if ((td->td_proc->p_flag & P_THREADED) == 0) { 295 /* We only care about the kse in the run queue. */ 296 td->td_priority = newpri; 297 if (ke->ke_rqindex != (newpri / RQ_PPQ)) { 298 sched_rem(ke); 299 sched_add(ke); 300 } 301 return; 302 } 303 304 /* It is a threaded process */ 305 kg = td->td_ksegrp; 306 kg->kg_runnable--; 307 TD_SET_CAN_RUN(td); 308 if (ke) { 309 if (kg->kg_last_assigned == td) { 310 kg->kg_last_assigned = 311 TAILQ_PREV(td, threadqueue, td_runq); 312 } 313 sched_rem(ke); 314 } 315 TAILQ_REMOVE(&kg->kg_runq, td, td_runq); 316 td->td_priority = newpri; 317 setrunqueue(td); 318 } 319 320 void 321 setrunqueue(struct thread *td) 322 { 323 struct kse *ke; 324 struct ksegrp *kg; 325 struct thread *td2; 326 struct thread *tda; 327 328 CTR1(KTR_RUNQ, "setrunqueue: td%p", td); 329 mtx_assert(&sched_lock, MA_OWNED); 330 KASSERT((TD_CAN_RUN(td) || TD_IS_RUNNING(td)), 331 ("setrunqueue: bad thread state")); 332 TD_SET_RUNQ(td); 333 kg = td->td_ksegrp; 334 kg->kg_runnable++; 335 if ((td->td_proc->p_flag & P_THREADED) == 0) { 336 /* 337 * Common path optimisation: Only one of everything 338 * and the KSE is always already attached. 339 * Totally ignore the ksegrp run queue. 340 */ 341 sched_add(td->td_kse); 342 return; 343 } 344 345 tda = kg->kg_last_assigned; 346 if ((ke = td->td_kse) == NULL) { 347 if (kg->kg_idle_kses) { 348 /* 349 * There is a free one so it's ours for the asking.. 350 */ 351 ke = TAILQ_FIRST(&kg->kg_iq); 352 TAILQ_REMOVE(&kg->kg_iq, ke, ke_kgrlist); 353 ke->ke_state = KES_THREAD; 354 kg->kg_idle_kses--; 355 } else if (tda && (tda->td_priority > td->td_priority)) { 356 /* 357 * None free, but there is one we can commandeer. 358 */ 359 ke = tda->td_kse; 360 tda->td_kse = NULL; 361 ke->ke_thread = NULL; 362 tda = kg->kg_last_assigned = 363 TAILQ_PREV(tda, threadqueue, td_runq); 364 sched_rem(ke); 365 } 366 } else { 367 /* 368 * Temporarily disassociate so it looks like the other cases. 369 */ 370 ke->ke_thread = NULL; 371 td->td_kse = NULL; 372 } 373 374 /* 375 * Add the thread to the ksegrp's run queue at 376 * the appropriate place. 377 */ 378 TAILQ_FOREACH(td2, &kg->kg_runq, td_runq) { 379 if (td2->td_priority > td->td_priority) { 380 TAILQ_INSERT_BEFORE(td2, td, td_runq); 381 break; 382 } 383 } 384 if (td2 == NULL) { 385 /* We ran off the end of the TAILQ or it was empty. */ 386 TAILQ_INSERT_TAIL(&kg->kg_runq, td, td_runq); 387 } 388 389 /* 390 * If we have a ke to use, then put it on the run queue and 391 * If needed, readjust the last_assigned pointer. 392 */ 393 if (ke) { 394 if (tda == NULL) { 395 /* 396 * No pre-existing last assigned so whoever is first 397 * gets the KSE we brought in.. (maybe us) 398 */ 399 td2 = TAILQ_FIRST(&kg->kg_runq); 400 KASSERT((td2->td_kse == NULL), 401 ("unexpected ke present")); 402 td2->td_kse = ke; 403 ke->ke_thread = td2; 404 kg->kg_last_assigned = td2; 405 } else if (tda->td_priority > td->td_priority) { 406 /* 407 * It's ours, grab it, but last_assigned is past us 408 * so don't change it. 409 */ 410 td->td_kse = ke; 411 ke->ke_thread = td; 412 } else { 413 /* 414 * We are past last_assigned, so 415 * put the new kse on whatever is next, 416 * which may or may not be us. 417 */ 418 td2 = TAILQ_NEXT(tda, td_runq); 419 kg->kg_last_assigned = td2; 420 td2->td_kse = ke; 421 ke->ke_thread = td2; 422 } 423 sched_add(ke); 424 } 425 } 426 427 /************************************************************************ 428 * Critical section marker functions * 429 ************************************************************************/ 430 /* Critical sections that prevent preemption. */ 431 void 432 critical_enter(void) 433 { 434 struct thread *td; 435 436 td = curthread; 437 if (td->td_critnest == 0) 438 cpu_critical_enter(); 439 td->td_critnest++; 440 } 441 442 void 443 critical_exit(void) 444 { 445 struct thread *td; 446 447 td = curthread; 448 if (td->td_critnest == 1) { 449 td->td_critnest = 0; 450 cpu_critical_exit(); 451 } else { 452 td->td_critnest--; 453 } 454 } 455 456 457 /************************************************************************ 458 * SYSTEM RUN QUEUE manipulations and tests * 459 ************************************************************************/ 460 /* 461 * Initialize a run structure. 462 */ 463 void 464 runq_init(struct runq *rq) 465 { 466 int i; 467 468 bzero(rq, sizeof *rq); 469 for (i = 0; i < RQ_NQS; i++) 470 TAILQ_INIT(&rq->rq_queues[i]); 471 } 472 473 /* 474 * Clear the status bit of the queue corresponding to priority level pri, 475 * indicating that it is empty. 476 */ 477 static __inline void 478 runq_clrbit(struct runq *rq, int pri) 479 { 480 struct rqbits *rqb; 481 482 rqb = &rq->rq_status; 483 CTR4(KTR_RUNQ, "runq_clrbit: bits=%#x %#x bit=%#x word=%d", 484 rqb->rqb_bits[RQB_WORD(pri)], 485 rqb->rqb_bits[RQB_WORD(pri)] & ~RQB_BIT(pri), 486 RQB_BIT(pri), RQB_WORD(pri)); 487 rqb->rqb_bits[RQB_WORD(pri)] &= ~RQB_BIT(pri); 488 } 489 490 /* 491 * Find the index of the first non-empty run queue. This is done by 492 * scanning the status bits, a set bit indicates a non-empty queue. 493 */ 494 static __inline int 495 runq_findbit(struct runq *rq) 496 { 497 struct rqbits *rqb; 498 int pri; 499 int i; 500 501 rqb = &rq->rq_status; 502 for (i = 0; i < RQB_LEN; i++) 503 if (rqb->rqb_bits[i]) { 504 pri = RQB_FFS(rqb->rqb_bits[i]) + (i << RQB_L2BPW); 505 CTR3(KTR_RUNQ, "runq_findbit: bits=%#x i=%d pri=%d", 506 rqb->rqb_bits[i], i, pri); 507 return (pri); 508 } 509 510 return (-1); 511 } 512 513 /* 514 * Set the status bit of the queue corresponding to priority level pri, 515 * indicating that it is non-empty. 516 */ 517 static __inline void 518 runq_setbit(struct runq *rq, int pri) 519 { 520 struct rqbits *rqb; 521 522 rqb = &rq->rq_status; 523 CTR4(KTR_RUNQ, "runq_setbit: bits=%#x %#x bit=%#x word=%d", 524 rqb->rqb_bits[RQB_WORD(pri)], 525 rqb->rqb_bits[RQB_WORD(pri)] | RQB_BIT(pri), 526 RQB_BIT(pri), RQB_WORD(pri)); 527 rqb->rqb_bits[RQB_WORD(pri)] |= RQB_BIT(pri); 528 } 529 530 /* 531 * Add the KSE to the queue specified by its priority, and set the 532 * corresponding status bit. 533 */ 534 void 535 runq_add(struct runq *rq, struct kse *ke) 536 { 537 struct rqhead *rqh; 538 int pri; 539 540 pri = ke->ke_thread->td_priority / RQ_PPQ; 541 ke->ke_rqindex = pri; 542 runq_setbit(rq, pri); 543 rqh = &rq->rq_queues[pri]; 544 CTR4(KTR_RUNQ, "runq_add: p=%p pri=%d %d rqh=%p", 545 ke->ke_proc, ke->ke_thread->td_priority, pri, rqh); 546 TAILQ_INSERT_TAIL(rqh, ke, ke_procq); 547 } 548 549 /* 550 * Return true if there are runnable processes of any priority on the run 551 * queue, false otherwise. Has no side effects, does not modify the run 552 * queue structure. 553 */ 554 int 555 runq_check(struct runq *rq) 556 { 557 struct rqbits *rqb; 558 int i; 559 560 rqb = &rq->rq_status; 561 for (i = 0; i < RQB_LEN; i++) 562 if (rqb->rqb_bits[i]) { 563 CTR2(KTR_RUNQ, "runq_check: bits=%#x i=%d", 564 rqb->rqb_bits[i], i); 565 return (1); 566 } 567 CTR0(KTR_RUNQ, "runq_check: empty"); 568 569 return (0); 570 } 571 572 /* 573 * Find the highest priority process on the run queue. 574 */ 575 struct kse * 576 runq_choose(struct runq *rq) 577 { 578 struct rqhead *rqh; 579 struct kse *ke; 580 int pri; 581 582 mtx_assert(&sched_lock, MA_OWNED); 583 while ((pri = runq_findbit(rq)) != -1) { 584 rqh = &rq->rq_queues[pri]; 585 ke = TAILQ_FIRST(rqh); 586 KASSERT(ke != NULL, ("runq_choose: no proc on busy queue")); 587 CTR3(KTR_RUNQ, 588 "runq_choose: pri=%d kse=%p rqh=%p", pri, ke, rqh); 589 return (ke); 590 } 591 CTR1(KTR_RUNQ, "runq_choose: idleproc pri=%d", pri); 592 593 return (NULL); 594 } 595 596 /* 597 * Remove the KSE from the queue specified by its priority, and clear the 598 * corresponding status bit if the queue becomes empty. 599 * Caller must set ke->ke_state afterwards. 600 */ 601 void 602 runq_remove(struct runq *rq, struct kse *ke) 603 { 604 struct rqhead *rqh; 605 int pri; 606 607 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 608 ("runq_remove: process swapped out")); 609 pri = ke->ke_rqindex; 610 rqh = &rq->rq_queues[pri]; 611 CTR4(KTR_RUNQ, "runq_remove: p=%p pri=%d %d rqh=%p", 612 ke, ke->ke_thread->td_priority, pri, rqh); 613 KASSERT(ke != NULL, ("runq_remove: no proc on busy queue")); 614 TAILQ_REMOVE(rqh, ke, ke_procq); 615 if (TAILQ_EMPTY(rqh)) { 616 CTR0(KTR_RUNQ, "runq_remove: empty"); 617 runq_clrbit(rq, pri); 618 } 619 } 620 621 #if 0 622 void 623 panc(char *string1, char *string2) 624 { 625 printf("%s", string1); 626 Debugger(string2); 627 } 628 629 void 630 thread_sanity_check(struct thread *td, char *string) 631 { 632 struct proc *p; 633 struct ksegrp *kg; 634 struct kse *ke; 635 struct thread *td2 = NULL; 636 unsigned int prevpri; 637 int saw_lastassigned = 0; 638 int unassigned = 0; 639 int assigned = 0; 640 641 p = td->td_proc; 642 kg = td->td_ksegrp; 643 ke = td->td_kse; 644 645 646 if (ke) { 647 if (p != ke->ke_proc) { 648 panc(string, "wrong proc"); 649 } 650 if (ke->ke_thread != td) { 651 panc(string, "wrong thread"); 652 } 653 } 654 655 if ((p->p_flag & P_THREADED) == 0) { 656 if (ke == NULL) { 657 panc(string, "non KSE thread lost kse"); 658 } 659 } else { 660 prevpri = 0; 661 saw_lastassigned = 0; 662 unassigned = 0; 663 assigned = 0; 664 TAILQ_FOREACH(td2, &kg->kg_runq, td_runq) { 665 if (td2->td_priority < prevpri) { 666 panc(string, "thread runqueue unosorted"); 667 } 668 if ((td2->td_state == TDS_RUNQ) && 669 td2->td_kse && 670 (td2->td_kse->ke_state != KES_ONRUNQ)) { 671 panc(string, "KSE wrong state"); 672 } 673 prevpri = td2->td_priority; 674 if (td2->td_kse) { 675 assigned++; 676 if (unassigned) { 677 panc(string, "unassigned before assigned"); 678 } 679 if (kg->kg_last_assigned == NULL) { 680 panc(string, "lastassigned corrupt"); 681 } 682 if (saw_lastassigned) { 683 panc(string, "last assigned not last"); 684 } 685 if (td2->td_kse->ke_thread != td2) { 686 panc(string, "mismatched kse/thread"); 687 } 688 } else { 689 unassigned++; 690 } 691 if (td2 == kg->kg_last_assigned) { 692 saw_lastassigned = 1; 693 if (td2->td_kse == NULL) { 694 panc(string, "last assigned not assigned"); 695 } 696 } 697 } 698 if (kg->kg_last_assigned && (saw_lastassigned == 0)) { 699 panc(string, "where on earth does lastassigned point?"); 700 } 701 #if 0 702 FOREACH_THREAD_IN_GROUP(kg, td2) { 703 if (((td2->td_flags & TDF_UNBOUND) == 0) && 704 (TD_ON_RUNQ(td2))) { 705 assigned++; 706 if (td2->td_kse == NULL) { 707 panc(string, "BOUND thread with no KSE"); 708 } 709 } 710 } 711 #endif 712 #if 0 713 if ((unassigned + assigned) != kg->kg_runnable) { 714 panc(string, "wrong number in runnable"); 715 } 716 #endif 717 } 718 if (assigned == 12345) { 719 printf("%p %p %p %p %p %d, %d", 720 td, td2, ke, kg, p, assigned, saw_lastassigned); 721 } 722 } 723 #endif 724
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