sched_ule.c revision 165819
1/*- 2 * Copyright (c) 2002-2007, Jeffrey Roberson <jeff@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 unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/sys/kern/sched_ule.c 165819 2007-01-05 23:45:38Z jeff $"); 29 30#include "opt_hwpmc_hooks.h" 31#include "opt_sched.h" 32 33#include <sys/param.h> 34#include <sys/systm.h> 35#include <sys/kdb.h> 36#include <sys/kernel.h> 37#include <sys/ktr.h> 38#include <sys/lock.h> 39#include <sys/mutex.h> 40#include <sys/proc.h> 41#include <sys/resource.h> 42#include <sys/resourcevar.h> 43#include <sys/sched.h> 44#include <sys/smp.h> 45#include <sys/sx.h> 46#include <sys/sysctl.h> 47#include <sys/sysproto.h> 48#include <sys/turnstile.h> 49#include <sys/umtx.h> 50#include <sys/vmmeter.h> 51#ifdef KTRACE 52#include <sys/uio.h> 53#include <sys/ktrace.h> 54#endif 55 56#ifdef HWPMC_HOOKS 57#include <sys/pmckern.h> 58#endif 59 60#include <machine/cpu.h> 61#include <machine/smp.h> 62 63/* 64 * Thread scheduler specific section. 65 */ 66struct td_sched { 67 TAILQ_ENTRY(td_sched) ts_procq; /* (j/z) Run queue. */ 68 int ts_flags; /* (j) TSF_* flags. */ 69 struct thread *ts_thread; /* (*) Active associated thread. */ 70 fixpt_t ts_pctcpu; /* (j) %cpu during p_swtime. */ 71 u_char ts_rqindex; /* (j) Run queue index. */ 72 enum { 73 TSS_THREAD, 74 TSS_ONRUNQ 75 } ts_state; /* (j) thread sched specific status. */ 76 int ts_slptime; 77 int ts_slice; 78 struct runq *ts_runq; 79 u_char ts_cpu; /* CPU that we have affinity for. */ 80 /* The following variables are only used for pctcpu calculation */ 81 int ts_ltick; /* Last tick that we were running on */ 82 int ts_ftick; /* First tick that we were running on */ 83 int ts_ticks; /* Tick count */ 84 85 /* originally from kg_sched */ 86 int skg_slptime; /* Number of ticks we vol. slept */ 87 int skg_runtime; /* Number of ticks we were running */ 88}; 89#define ts_assign ts_procq.tqe_next 90/* flags kept in ts_flags */ 91#define TSF_ASSIGNED 0x0001 /* Thread is being migrated. */ 92#define TSF_BOUND 0x0002 /* Thread can not migrate. */ 93#define TSF_XFERABLE 0x0004 /* Thread was added as transferable. */ 94#define TSF_HOLD 0x0008 /* Thread is temporarily bound. */ 95#define TSF_REMOVED 0x0010 /* Thread was removed while ASSIGNED */ 96#define TSF_INTERNAL 0x0020 /* Thread added due to migration. */ 97#define TSF_DIDRUN 0x2000 /* Thread actually ran. */ 98#define TSF_EXIT 0x4000 /* Thread is being killed. */ 99 100static struct td_sched td_sched0; 101 102/* 103 * Cpu percentage computation macros and defines. 104 * 105 * SCHED_TICK_SECS: Number of seconds to average the cpu usage across. 106 * SCHED_TICK_TARG: Number of hz ticks to average the cpu usage across. 107 * SCHED_TICK_MAX: Maximum number of ticks before scaling back. 108 * SCHED_TICK_SHIFT: Shift factor to avoid rounding away results. 109 * SCHED_TICK_HZ: Compute the number of hz ticks for a given ticks count. 110 * SCHED_TICK_TOTAL: Gives the amount of time we've been recording ticks. 111 */ 112#define SCHED_TICK_SECS 10 113#define SCHED_TICK_TARG (hz * SCHED_TICK_SECS) 114#define SCHED_TICK_MAX (SCHED_TICK_TARG + hz) 115#define SCHED_TICK_SHIFT 10 116#define SCHED_TICK_HZ(ts) ((ts)->ts_ticks >> SCHED_TICK_SHIFT) 117#define SCHED_TICK_TOTAL(ts) ((ts)->ts_ltick - (ts)->ts_ftick) 118 119/* 120 * These macros determine priorities for non-interactive threads. They are 121 * assigned a priority based on their recent cpu utilization as expressed 122 * by the ratio of ticks to the tick total. NHALF priorities at the start 123 * and end of the MIN to MAX timeshare range are only reachable with negative 124 * or positive nice respectively. 125 * 126 * PRI_RANGE: Priority range for utilization dependent priorities. 127 * PRI_NRESV: Number of nice values. 128 * PRI_TICKS: Compute a priority in PRI_RANGE from the ticks count and total. 129 * PRI_NICE: Determines the part of the priority inherited from nice. 130 */ 131#define SCHED_PRI_NRESV (PRIO_MAX - PRIO_MIN) 132#define SCHED_PRI_NHALF (SCHED_PRI_NRESV / 2) 133#define SCHED_PRI_MIN (PRI_MIN_TIMESHARE + SCHED_PRI_NHALF) 134#define SCHED_PRI_MAX (PRI_MAX_TIMESHARE - SCHED_PRI_NHALF) 135#define SCHED_PRI_RANGE (SCHED_PRI_MAX - SCHED_PRI_MIN + 1) 136#define SCHED_PRI_TICKS(ts) \ 137 (SCHED_TICK_HZ((ts)) / \ 138 (max(SCHED_TICK_TOTAL((ts)), SCHED_PRI_RANGE) / SCHED_PRI_RANGE)) 139#define SCHED_PRI_NICE(nice) (nice) 140 141/* 142 * These determine the interactivity of a process. Interactivity differs from 143 * cpu utilization in that it expresses the voluntary time slept vs time ran 144 * while cpu utilization includes all time not running. This more accurately 145 * models the intent of the thread. 146 * 147 * SLP_RUN_MAX: Maximum amount of sleep time + run time we'll accumulate 148 * before throttling back. 149 * SLP_RUN_FORK: Maximum slp+run time to inherit at fork time. 150 * INTERACT_MAX: Maximum interactivity value. Smaller is better. 151 * INTERACT_THRESH: Threshhold for placement on the current runq. 152 */ 153#define SCHED_SLP_RUN_MAX ((hz * 5) << SCHED_TICK_SHIFT) 154#define SCHED_SLP_RUN_FORK ((hz / 2) << SCHED_TICK_SHIFT) 155#define SCHED_INTERACT_MAX (100) 156#define SCHED_INTERACT_HALF (SCHED_INTERACT_MAX / 2) 157#define SCHED_INTERACT_THRESH (30) 158 159/* 160 * tickincr: Converts a stathz tick into a hz domain scaled by 161 * the shift factor. Without the shift the error rate 162 * due to rounding would be unacceptably high. 163 * realstathz: stathz is sometimes 0 and run off of hz. 164 * sched_slice: Runtime of each thread before rescheduling. 165 */ 166static int sched_interact = SCHED_INTERACT_THRESH; 167static int realstathz; 168static int tickincr; 169static int sched_slice; 170static int sched_rebalance; 171 172/* 173 * tdq - per processor runqs and statistics. 174 */ 175struct tdq { 176 struct runq tdq_idle; /* Queue of IDLE threads. */ 177 struct runq tdq_timeshare; /* timeshare run queue. */ 178 struct runq tdq_realtime; /* real-time run queue. */ 179 int tdq_idx; /* Current insert index. */ 180 int tdq_ridx; /* Current removal index. */ 181 int tdq_load_timeshare; /* Load for timeshare. */ 182 int tdq_load; /* Aggregate load. */ 183#ifdef SMP 184 int tdq_transferable; 185 LIST_ENTRY(tdq) tdq_siblings; /* Next in tdq group. */ 186 struct tdq_group *tdq_group; /* Our processor group. */ 187 volatile struct td_sched *tdq_assigned; /* assigned by another CPU. */ 188#else 189 int tdq_sysload; /* For loadavg, !ITHD load. */ 190#endif 191}; 192 193#ifdef SMP 194/* 195 * tdq groups are groups of processors which can cheaply share threads. When 196 * one processor in the group goes idle it will check the runqs of the other 197 * processors in its group prior to halting and waiting for an interrupt. 198 * These groups are suitable for SMT (Symetric Multi-Threading) and not NUMA. 199 * In a numa environment we'd want an idle bitmap per group and a two tiered 200 * load balancer. 201 */ 202struct tdq_group { 203 int tdg_cpus; /* Count of CPUs in this tdq group. */ 204 cpumask_t tdg_cpumask; /* Mask of cpus in this group. */ 205 cpumask_t tdg_idlemask; /* Idle cpus in this group. */ 206 cpumask_t tdg_mask; /* Bit mask for first cpu. */ 207 int tdg_load; /* Total load of this group. */ 208 int tdg_transferable; /* Transferable load of this group. */ 209 LIST_HEAD(, tdq) tdg_members; /* Linked list of all members. */ 210}; 211#endif 212 213/* 214 * One thread queue per processor. 215 */ 216#ifdef SMP 217static cpumask_t tdq_idle; 218static int tdg_maxid; 219static struct tdq tdq_cpu[MAXCPU]; 220static struct tdq_group tdq_groups[MAXCPU]; 221static int bal_tick; 222static int gbal_tick; 223static int balance_groups; 224 225#define TDQ_SELF() (&tdq_cpu[PCPU_GET(cpuid)]) 226#define TDQ_CPU(x) (&tdq_cpu[(x)]) 227#define TDQ_ID(x) ((x) - tdq_cpu) 228#define TDQ_GROUP(x) (&tdq_groups[(x)]) 229#else /* !SMP */ 230static struct tdq tdq_cpu; 231 232#define TDQ_SELF() (&tdq_cpu) 233#define TDQ_CPU(x) (&tdq_cpu) 234#endif 235 236static struct td_sched *sched_choose(void); /* XXX Should be thread * */ 237static void sched_priority(struct thread *); 238static void sched_thread_priority(struct thread *, u_char); 239static int sched_interact_score(struct thread *); 240static void sched_interact_update(struct thread *); 241static void sched_interact_fork(struct thread *); 242static void sched_pctcpu_update(struct td_sched *); 243 244/* Operations on per processor queues */ 245static struct td_sched * tdq_choose(struct tdq *); 246static void tdq_setup(struct tdq *); 247static void tdq_load_add(struct tdq *, struct td_sched *); 248static void tdq_load_rem(struct tdq *, struct td_sched *); 249static __inline void tdq_runq_add(struct tdq *, struct td_sched *, int); 250static __inline void tdq_runq_rem(struct tdq *, struct td_sched *); 251void tdq_print(int cpu); 252static void runq_print(struct runq *rq); 253#ifdef SMP 254static int tdq_transfer(struct tdq *, struct td_sched *, int); 255static struct td_sched *runq_steal(struct runq *); 256static void sched_balance(void); 257static void sched_balance_groups(void); 258static void sched_balance_group(struct tdq_group *); 259static void sched_balance_pair(struct tdq *, struct tdq *); 260static void sched_smp_tick(void); 261static void tdq_move(struct tdq *, int); 262static int tdq_idled(struct tdq *); 263static void tdq_notify(struct td_sched *, int); 264static void tdq_assign(struct tdq *); 265static struct td_sched *tdq_steal(struct tdq *, int); 266#define THREAD_CAN_MIGRATE(td) \ 267 ((td)->td_pinned == 0 && (td)->td_pri_class != PRI_ITHD) 268#endif 269 270static void sched_setup(void *dummy); 271SYSINIT(sched_setup, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, sched_setup, NULL) 272 273static void sched_initticks(void *dummy); 274SYSINIT(sched_initticks, SI_SUB_CLOCKS, SI_ORDER_THIRD, sched_initticks, NULL) 275 276static void 277runq_print(struct runq *rq) 278{ 279 struct rqhead *rqh; 280 struct td_sched *ts; 281 int pri; 282 int j; 283 int i; 284 285 for (i = 0; i < RQB_LEN; i++) { 286 printf("\t\trunq bits %d 0x%zx\n", 287 i, rq->rq_status.rqb_bits[i]); 288 for (j = 0; j < RQB_BPW; j++) 289 if (rq->rq_status.rqb_bits[i] & (1ul << j)) { 290 pri = j + (i << RQB_L2BPW); 291 rqh = &rq->rq_queues[pri]; 292 TAILQ_FOREACH(ts, rqh, ts_procq) { 293 printf("\t\t\ttd %p(%s) priority %d rqindex %d pri %d\n", 294 ts->ts_thread, ts->ts_thread->td_proc->p_comm, ts->ts_thread->td_priority, ts->ts_rqindex, pri); 295 } 296 } 297 } 298} 299 300void 301tdq_print(int cpu) 302{ 303 struct tdq *tdq; 304 305 tdq = TDQ_CPU(cpu); 306 307 printf("tdq:\n"); 308 printf("\tload: %d\n", tdq->tdq_load); 309 printf("\tload TIMESHARE: %d\n", tdq->tdq_load_timeshare); 310 printf("\ttimeshare idx: %d\n", tdq->tdq_idx); 311 printf("\ttimeshare ridx: %d\n", tdq->tdq_ridx); 312 printf("\trealtime runq:\n"); 313 runq_print(&tdq->tdq_realtime); 314 printf("\ttimeshare runq:\n"); 315 runq_print(&tdq->tdq_timeshare); 316 printf("\tidle runq:\n"); 317 runq_print(&tdq->tdq_idle); 318#ifdef SMP 319 printf("\tload transferable: %d\n", tdq->tdq_transferable); 320#endif 321} 322 323static __inline void 324tdq_runq_add(struct tdq *tdq, struct td_sched *ts, int flags) 325{ 326#ifdef SMP 327 if (THREAD_CAN_MIGRATE(ts->ts_thread)) { 328 tdq->tdq_transferable++; 329 tdq->tdq_group->tdg_transferable++; 330 ts->ts_flags |= TSF_XFERABLE; 331 } 332#endif 333 if (ts->ts_runq == &tdq->tdq_timeshare) { 334 int pri; 335 336 pri = ts->ts_thread->td_priority; 337 KASSERT(pri <= PRI_MAX_TIMESHARE && pri >= PRI_MIN_TIMESHARE, 338 ("Invalid priority %d on timeshare runq", pri)); 339 /* 340 * This queue contains only priorities between MIN and MAX 341 * realtime. Use the whole queue to represent these values. 342 */ 343#define TS_RQ_PPQ (((PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE) + 1) / RQ_NQS) 344 if ((flags & SRQ_BORROWING) == 0) { 345 pri = (pri - PRI_MIN_TIMESHARE) / TS_RQ_PPQ; 346 pri = (pri + tdq->tdq_idx) % RQ_NQS; 347 /* 348 * This effectively shortens the queue by one so we 349 * can have a one slot difference between idx and 350 * ridx while we wait for threads to drain. 351 */ 352 if (tdq->tdq_ridx != tdq->tdq_idx && 353 pri == tdq->tdq_ridx) 354 pri = (pri - 1) % RQ_NQS; 355 } else 356 pri = tdq->tdq_ridx; 357 runq_add_pri(ts->ts_runq, ts, pri, flags); 358 } else 359 runq_add(ts->ts_runq, ts, flags); 360} 361 362static __inline void 363tdq_runq_rem(struct tdq *tdq, struct td_sched *ts) 364{ 365#ifdef SMP 366 if (ts->ts_flags & TSF_XFERABLE) { 367 tdq->tdq_transferable--; 368 tdq->tdq_group->tdg_transferable--; 369 ts->ts_flags &= ~TSF_XFERABLE; 370 } 371#endif 372 if (ts->ts_runq == &tdq->tdq_timeshare) { 373 if (tdq->tdq_idx != tdq->tdq_ridx) 374 runq_remove_idx(ts->ts_runq, ts, &tdq->tdq_ridx); 375 else 376 runq_remove_idx(ts->ts_runq, ts, NULL); 377 /* 378 * For timeshare threads we update the priority here so 379 * the priority reflects the time we've been sleeping. 380 */ 381 ts->ts_ltick = ticks; 382 sched_pctcpu_update(ts); 383 sched_priority(ts->ts_thread); 384 } else 385 runq_remove(ts->ts_runq, ts); 386} 387 388static void 389tdq_load_add(struct tdq *tdq, struct td_sched *ts) 390{ 391 int class; 392 mtx_assert(&sched_lock, MA_OWNED); 393 class = PRI_BASE(ts->ts_thread->td_pri_class); 394 if (class == PRI_TIMESHARE) 395 tdq->tdq_load_timeshare++; 396 tdq->tdq_load++; 397 CTR1(KTR_SCHED, "load: %d", tdq->tdq_load); 398 if (class != PRI_ITHD && (ts->ts_thread->td_proc->p_flag & P_NOLOAD) == 0) 399#ifdef SMP 400 tdq->tdq_group->tdg_load++; 401#else 402 tdq->tdq_sysload++; 403#endif 404} 405 406static void 407tdq_load_rem(struct tdq *tdq, struct td_sched *ts) 408{ 409 int class; 410 mtx_assert(&sched_lock, MA_OWNED); 411 class = PRI_BASE(ts->ts_thread->td_pri_class); 412 if (class == PRI_TIMESHARE) 413 tdq->tdq_load_timeshare--; 414 if (class != PRI_ITHD && (ts->ts_thread->td_proc->p_flag & P_NOLOAD) == 0) 415#ifdef SMP 416 tdq->tdq_group->tdg_load--; 417#else 418 tdq->tdq_sysload--; 419#endif 420 tdq->tdq_load--; 421 CTR1(KTR_SCHED, "load: %d", tdq->tdq_load); 422 ts->ts_runq = NULL; 423} 424 425#ifdef SMP 426static void 427sched_smp_tick(void) 428{ 429 struct tdq *tdq; 430 431 tdq = TDQ_SELF(); 432 if (sched_rebalance) { 433 if (ticks >= bal_tick) 434 sched_balance(); 435 if (ticks >= gbal_tick && balance_groups) 436 sched_balance_groups(); 437 } 438 /* 439 * We could have been assigned a non real-time thread without an 440 * IPI. 441 */ 442 if (tdq->tdq_assigned) 443 tdq_assign(tdq); /* Potentially sets NEEDRESCHED */ 444} 445 446/* 447 * sched_balance is a simple CPU load balancing algorithm. It operates by 448 * finding the least loaded and most loaded cpu and equalizing their load 449 * by migrating some processes. 450 * 451 * Dealing only with two CPUs at a time has two advantages. Firstly, most 452 * installations will only have 2 cpus. Secondly, load balancing too much at 453 * once can have an unpleasant effect on the system. The scheduler rarely has 454 * enough information to make perfect decisions. So this algorithm chooses 455 * algorithm simplicity and more gradual effects on load in larger systems. 456 * 457 * It could be improved by considering the priorities and slices assigned to 458 * each task prior to balancing them. There are many pathological cases with 459 * any approach and so the semi random algorithm below may work as well as any. 460 * 461 */ 462static void 463sched_balance(void) 464{ 465 struct tdq_group *high; 466 struct tdq_group *low; 467 struct tdq_group *tdg; 468 int cnt; 469 int i; 470 471 bal_tick = ticks + (random() % (hz * 2)); 472 if (smp_started == 0) 473 return; 474 low = high = NULL; 475 i = random() % (tdg_maxid + 1); 476 for (cnt = 0; cnt <= tdg_maxid; cnt++) { 477 tdg = TDQ_GROUP(i); 478 /* 479 * Find the CPU with the highest load that has some 480 * threads to transfer. 481 */ 482 if ((high == NULL || tdg->tdg_load > high->tdg_load) 483 && tdg->tdg_transferable) 484 high = tdg; 485 if (low == NULL || tdg->tdg_load < low->tdg_load) 486 low = tdg; 487 if (++i > tdg_maxid) 488 i = 0; 489 } 490 if (low != NULL && high != NULL && high != low) 491 sched_balance_pair(LIST_FIRST(&high->tdg_members), 492 LIST_FIRST(&low->tdg_members)); 493} 494 495static void 496sched_balance_groups(void) 497{ 498 int i; 499 500 gbal_tick = ticks + (random() % (hz * 2)); 501 mtx_assert(&sched_lock, MA_OWNED); 502 if (smp_started) 503 for (i = 0; i <= tdg_maxid; i++) 504 sched_balance_group(TDQ_GROUP(i)); 505} 506 507static void 508sched_balance_group(struct tdq_group *tdg) 509{ 510 struct tdq *tdq; 511 struct tdq *high; 512 struct tdq *low; 513 int load; 514 515 if (tdg->tdg_transferable == 0) 516 return; 517 low = NULL; 518 high = NULL; 519 LIST_FOREACH(tdq, &tdg->tdg_members, tdq_siblings) { 520 load = tdq->tdq_load; 521 if (high == NULL || load > high->tdq_load) 522 high = tdq; 523 if (low == NULL || load < low->tdq_load) 524 low = tdq; 525 } 526 if (high != NULL && low != NULL && high != low) 527 sched_balance_pair(high, low); 528} 529 530static void 531sched_balance_pair(struct tdq *high, struct tdq *low) 532{ 533 int transferable; 534 int high_load; 535 int low_load; 536 int move; 537 int diff; 538 int i; 539 540 /* 541 * If we're transfering within a group we have to use this specific 542 * tdq's transferable count, otherwise we can steal from other members 543 * of the group. 544 */ 545 if (high->tdq_group == low->tdq_group) { 546 transferable = high->tdq_transferable; 547 high_load = high->tdq_load; 548 low_load = low->tdq_load; 549 } else { 550 transferable = high->tdq_group->tdg_transferable; 551 high_load = high->tdq_group->tdg_load; 552 low_load = low->tdq_group->tdg_load; 553 } 554 if (transferable == 0) 555 return; 556 /* 557 * Determine what the imbalance is and then adjust that to how many 558 * threads we actually have to give up (transferable). 559 */ 560 diff = high_load - low_load; 561 move = diff / 2; 562 if (diff & 0x1) 563 move++; 564 move = min(move, transferable); 565 for (i = 0; i < move; i++) 566 tdq_move(high, TDQ_ID(low)); 567 return; 568} 569 570static void 571tdq_move(struct tdq *from, int cpu) 572{ 573 struct tdq *tdq; 574 struct tdq *to; 575 struct td_sched *ts; 576 577 tdq = from; 578 to = TDQ_CPU(cpu); 579 ts = tdq_steal(tdq, 1); 580 if (ts == NULL) { 581 struct tdq_group *tdg; 582 583 tdg = tdq->tdq_group; 584 LIST_FOREACH(tdq, &tdg->tdg_members, tdq_siblings) { 585 if (tdq == from || tdq->tdq_transferable == 0) 586 continue; 587 ts = tdq_steal(tdq, 1); 588 break; 589 } 590 if (ts == NULL) 591 panic("tdq_move: No threads available with a " 592 "transferable count of %d\n", 593 tdg->tdg_transferable); 594 } 595 if (tdq == to) 596 return; 597 ts->ts_state = TSS_THREAD; 598 tdq_runq_rem(tdq, ts); 599 tdq_load_rem(tdq, ts); 600 tdq_notify(ts, cpu); 601} 602 603static int 604tdq_idled(struct tdq *tdq) 605{ 606 struct tdq_group *tdg; 607 struct tdq *steal; 608 struct td_sched *ts; 609 610 tdg = tdq->tdq_group; 611 /* 612 * If we're in a cpu group, try and steal threads from another cpu in 613 * the group before idling. 614 */ 615 if (tdg->tdg_cpus > 1 && tdg->tdg_transferable) { 616 LIST_FOREACH(steal, &tdg->tdg_members, tdq_siblings) { 617 if (steal == tdq || steal->tdq_transferable == 0) 618 continue; 619 ts = tdq_steal(steal, 0); 620 if (ts == NULL) 621 continue; 622 ts->ts_state = TSS_THREAD; 623 tdq_runq_rem(steal, ts); 624 tdq_load_rem(steal, ts); 625 ts->ts_cpu = PCPU_GET(cpuid); 626 ts->ts_flags |= TSF_INTERNAL | TSF_HOLD; 627 sched_add(ts->ts_thread, SRQ_YIELDING); 628 return (0); 629 } 630 } 631 /* 632 * We only set the idled bit when all of the cpus in the group are 633 * idle. Otherwise we could get into a situation where a thread bounces 634 * back and forth between two idle cores on seperate physical CPUs. 635 */ 636 tdg->tdg_idlemask |= PCPU_GET(cpumask); 637 if (tdg->tdg_idlemask != tdg->tdg_cpumask) 638 return (1); 639 atomic_set_int(&tdq_idle, tdg->tdg_mask); 640 return (1); 641} 642 643static void 644tdq_assign(struct tdq *tdq) 645{ 646 struct td_sched *nts; 647 struct td_sched *ts; 648 649 do { 650 *(volatile struct td_sched **)&ts = tdq->tdq_assigned; 651 } while(!atomic_cmpset_ptr((volatile uintptr_t *)&tdq->tdq_assigned, 652 (uintptr_t)ts, (uintptr_t)NULL)); 653 for (; ts != NULL; ts = nts) { 654 nts = ts->ts_assign; 655 tdq->tdq_group->tdg_load--; 656 tdq->tdq_load--; 657 ts->ts_flags &= ~TSF_ASSIGNED; 658 if (ts->ts_flags & TSF_REMOVED) { 659 ts->ts_flags &= ~TSF_REMOVED; 660 continue; 661 } 662 ts->ts_flags |= TSF_INTERNAL | TSF_HOLD; 663 sched_add(ts->ts_thread, SRQ_YIELDING); 664 } 665} 666 667static void 668tdq_notify(struct td_sched *ts, int cpu) 669{ 670 struct tdq *tdq; 671 struct thread *td; 672 struct pcpu *pcpu; 673 int class; 674 int prio; 675 676 tdq = TDQ_CPU(cpu); 677 class = PRI_BASE(ts->ts_thread->td_pri_class); 678 if ((class != PRI_IDLE && class != PRI_ITHD) 679 && (tdq_idle & tdq->tdq_group->tdg_mask)) 680 atomic_clear_int(&tdq_idle, tdq->tdq_group->tdg_mask); 681 tdq->tdq_group->tdg_load++; 682 tdq->tdq_load++; 683 ts->ts_cpu = cpu; 684 ts->ts_flags |= TSF_ASSIGNED; 685 prio = ts->ts_thread->td_priority; 686 687 /* 688 * Place a thread on another cpu's queue and force a resched. 689 */ 690 do { 691 *(volatile struct td_sched **)&ts->ts_assign = tdq->tdq_assigned; 692 } while(!atomic_cmpset_ptr((volatile uintptr_t *)&tdq->tdq_assigned, 693 (uintptr_t)ts->ts_assign, (uintptr_t)ts)); 694 /* Only ipi for realtime/ithd priorities */ 695 if (ts->ts_thread->td_priority >= PRI_MIN_TIMESHARE) 696 return; 697 /* 698 * Without sched_lock we could lose a race where we set NEEDRESCHED 699 * on a thread that is switched out before the IPI is delivered. This 700 * would lead us to miss the resched. This will be a problem once 701 * sched_lock is pushed down. 702 */ 703 pcpu = pcpu_find(cpu); 704 td = pcpu->pc_curthread; 705 if (ts->ts_thread->td_priority < td->td_priority) { 706 td->td_flags |= TDF_NEEDRESCHED; 707 ipi_selected(1 << cpu, IPI_AST); 708 } 709} 710 711static struct td_sched * 712runq_steal(struct runq *rq) 713{ 714 struct rqhead *rqh; 715 struct rqbits *rqb; 716 struct td_sched *ts; 717 int word; 718 int bit; 719 720 mtx_assert(&sched_lock, MA_OWNED); 721 rqb = &rq->rq_status; 722 for (word = 0; word < RQB_LEN; word++) { 723 if (rqb->rqb_bits[word] == 0) 724 continue; 725 for (bit = 0; bit < RQB_BPW; bit++) { 726 if ((rqb->rqb_bits[word] & (1ul << bit)) == 0) 727 continue; 728 rqh = &rq->rq_queues[bit + (word << RQB_L2BPW)]; 729 TAILQ_FOREACH(ts, rqh, ts_procq) { 730 if (THREAD_CAN_MIGRATE(ts->ts_thread)) 731 return (ts); 732 } 733 } 734 } 735 return (NULL); 736} 737 738static struct td_sched * 739tdq_steal(struct tdq *tdq, int stealidle) 740{ 741 struct td_sched *ts; 742 743 /* 744 * Steal from next first to try to get a non-interactive task that 745 * may not have run for a while. 746 * XXX Need to effect steal order for timeshare threads. 747 */ 748 if ((ts = runq_steal(&tdq->tdq_realtime)) != NULL) 749 return (ts); 750 if ((ts = runq_steal(&tdq->tdq_timeshare)) != NULL) 751 return (ts); 752 if (stealidle) 753 return (runq_steal(&tdq->tdq_idle)); 754 return (NULL); 755} 756 757int 758tdq_transfer(struct tdq *tdq, struct td_sched *ts, int class) 759{ 760 struct tdq_group *ntdg; 761 struct tdq_group *tdg; 762 struct tdq *old; 763 int cpu; 764 int idx; 765 766 if (smp_started == 0) 767 return (0); 768 cpu = 0; 769 /* 770 * If our load exceeds a certain threshold we should attempt to 771 * reassign this thread. The first candidate is the cpu that 772 * originally ran the thread. If it is idle, assign it there, 773 * otherwise, pick an idle cpu. 774 * 775 * The threshold at which we start to reassign has a large impact 776 * on the overall performance of the system. Tuned too high and 777 * some CPUs may idle. Too low and there will be excess migration 778 * and context switches. 779 */ 780 old = TDQ_CPU(ts->ts_cpu); 781 ntdg = old->tdq_group; 782 tdg = tdq->tdq_group; 783 if (tdq_idle) { 784 if (tdq_idle & ntdg->tdg_mask) { 785 cpu = ffs(ntdg->tdg_idlemask); 786 if (cpu) { 787 CTR2(KTR_SCHED, 788 "tdq_transfer: %p found old cpu %X " 789 "in idlemask.", ts, cpu); 790 goto migrate; 791 } 792 } 793 /* 794 * Multiple cpus could find this bit simultaneously 795 * but the race shouldn't be terrible. 796 */ 797 cpu = ffs(tdq_idle); 798 if (cpu) { 799 CTR2(KTR_SCHED, "tdq_transfer: %p found %X " 800 "in idlemask.", ts, cpu); 801 goto migrate; 802 } 803 } 804 idx = 0; 805#if 0 806 if (old->tdq_load < tdq->tdq_load) { 807 cpu = ts->ts_cpu + 1; 808 CTR2(KTR_SCHED, "tdq_transfer: %p old cpu %X " 809 "load less than ours.", ts, cpu); 810 goto migrate; 811 } 812 /* 813 * No new CPU was found, look for one with less load. 814 */ 815 for (idx = 0; idx <= tdg_maxid; idx++) { 816 ntdg = TDQ_GROUP(idx); 817 if (ntdg->tdg_load /*+ (ntdg->tdg_cpus * 2)*/ < tdg->tdg_load) { 818 cpu = ffs(ntdg->tdg_cpumask); 819 CTR2(KTR_SCHED, "tdq_transfer: %p cpu %X load less " 820 "than ours.", ts, cpu); 821 goto migrate; 822 } 823 } 824#endif 825 /* 826 * If another cpu in this group has idled, assign a thread over 827 * to them after checking to see if there are idled groups. 828 */ 829 if (tdg->tdg_idlemask) { 830 cpu = ffs(tdg->tdg_idlemask); 831 if (cpu) { 832 CTR2(KTR_SCHED, "tdq_transfer: %p cpu %X idle in " 833 "group.", ts, cpu); 834 goto migrate; 835 } 836 } 837 return (0); 838migrate: 839 /* 840 * Now that we've found an idle CPU, migrate the thread. 841 */ 842 cpu--; 843 ts->ts_runq = NULL; 844 tdq_notify(ts, cpu); 845 846 return (1); 847} 848 849#endif /* SMP */ 850 851/* 852 * Pick the highest priority task we have and return it. 853 */ 854 855static struct td_sched * 856tdq_choose(struct tdq *tdq) 857{ 858 struct td_sched *ts; 859 860 mtx_assert(&sched_lock, MA_OWNED); 861 862 ts = runq_choose(&tdq->tdq_realtime); 863 if (ts != NULL) { 864 KASSERT(ts->ts_thread->td_priority <= PRI_MAX_REALTIME, 865 ("tdq_choose: Invalid priority on realtime queue %d", 866 ts->ts_thread->td_priority)); 867 return (ts); 868 } 869 ts = runq_choose_from(&tdq->tdq_timeshare, tdq->tdq_ridx); 870 if (ts != NULL) { 871 KASSERT(ts->ts_thread->td_priority <= PRI_MAX_TIMESHARE && 872 ts->ts_thread->td_priority >= PRI_MIN_TIMESHARE, 873 ("tdq_choose: Invalid priority on timeshare queue %d", 874 ts->ts_thread->td_priority)); 875 return (ts); 876 } 877 878 ts = runq_choose(&tdq->tdq_idle); 879 if (ts != NULL) { 880 KASSERT(ts->ts_thread->td_priority >= PRI_MIN_IDLE, 881 ("tdq_choose: Invalid priority on idle queue %d", 882 ts->ts_thread->td_priority)); 883 return (ts); 884 } 885 886 return (NULL); 887} 888 889static void 890tdq_setup(struct tdq *tdq) 891{ 892 runq_init(&tdq->tdq_realtime); 893 runq_init(&tdq->tdq_timeshare); 894 runq_init(&tdq->tdq_idle); 895 tdq->tdq_load = 0; 896 tdq->tdq_load_timeshare = 0; 897} 898 899static void 900sched_setup(void *dummy) 901{ 902#ifdef SMP 903 int i; 904#endif 905 906 /* 907 * To avoid divide-by-zero, we set realstathz a dummy value 908 * in case which sched_clock() called before sched_initticks(). 909 */ 910 realstathz = hz; 911 sched_slice = (realstathz/7); /* 140ms */ 912 tickincr = 1 << SCHED_TICK_SHIFT; 913 914#ifdef SMP 915 balance_groups = 0; 916 /* 917 * Initialize the tdqs. 918 */ 919 for (i = 0; i < MAXCPU; i++) { 920 struct tdq *tdq; 921 922 tdq = &tdq_cpu[i]; 923 tdq->tdq_assigned = NULL; 924 tdq_setup(&tdq_cpu[i]); 925 } 926 if (smp_topology == NULL) { 927 struct tdq_group *tdg; 928 struct tdq *tdq; 929 int cpus; 930 931 for (cpus = 0, i = 0; i < MAXCPU; i++) { 932 if (CPU_ABSENT(i)) 933 continue; 934 tdq = &tdq_cpu[i]; 935 tdg = &tdq_groups[cpus]; 936 /* 937 * Setup a tdq group with one member. 938 */ 939 tdq->tdq_transferable = 0; 940 tdq->tdq_group = tdg; 941 tdg->tdg_cpus = 1; 942 tdg->tdg_idlemask = 0; 943 tdg->tdg_cpumask = tdg->tdg_mask = 1 << i; 944 tdg->tdg_load = 0; 945 tdg->tdg_transferable = 0; 946 LIST_INIT(&tdg->tdg_members); 947 LIST_INSERT_HEAD(&tdg->tdg_members, tdq, tdq_siblings); 948 cpus++; 949 } 950 tdg_maxid = cpus - 1; 951 } else { 952 struct tdq_group *tdg; 953 struct cpu_group *cg; 954 int j; 955 956 for (i = 0; i < smp_topology->ct_count; i++) { 957 cg = &smp_topology->ct_group[i]; 958 tdg = &tdq_groups[i]; 959 /* 960 * Initialize the group. 961 */ 962 tdg->tdg_idlemask = 0; 963 tdg->tdg_load = 0; 964 tdg->tdg_transferable = 0; 965 tdg->tdg_cpus = cg->cg_count; 966 tdg->tdg_cpumask = cg->cg_mask; 967 LIST_INIT(&tdg->tdg_members); 968 /* 969 * Find all of the group members and add them. 970 */ 971 for (j = 0; j < MAXCPU; j++) { 972 if ((cg->cg_mask & (1 << j)) != 0) { 973 if (tdg->tdg_mask == 0) 974 tdg->tdg_mask = 1 << j; 975 tdq_cpu[j].tdq_transferable = 0; 976 tdq_cpu[j].tdq_group = tdg; 977 LIST_INSERT_HEAD(&tdg->tdg_members, 978 &tdq_cpu[j], tdq_siblings); 979 } 980 } 981 if (tdg->tdg_cpus > 1) 982 balance_groups = 1; 983 } 984 tdg_maxid = smp_topology->ct_count - 1; 985 } 986 /* 987 * Stagger the group and global load balancer so they do not 988 * interfere with each other. 989 */ 990 bal_tick = ticks + hz; 991 if (balance_groups) 992 gbal_tick = ticks + (hz / 2); 993#else 994 tdq_setup(TDQ_SELF()); 995#endif 996 mtx_lock_spin(&sched_lock); 997 tdq_load_add(TDQ_SELF(), &td_sched0); 998 mtx_unlock_spin(&sched_lock); 999} 1000 1001/* ARGSUSED */ 1002static void 1003sched_initticks(void *dummy) 1004{ 1005 mtx_lock_spin(&sched_lock); 1006 realstathz = stathz ? stathz : hz; 1007 sched_slice = (realstathz/7); /* ~140ms */ 1008 1009 /* 1010 * tickincr is shifted out by 10 to avoid rounding errors due to 1011 * hz not being evenly divisible by stathz on all platforms. 1012 */ 1013 tickincr = (hz << SCHED_TICK_SHIFT) / realstathz; 1014 /* 1015 * This does not work for values of stathz that are more than 1016 * 1 << SCHED_TICK_SHIFT * hz. In practice this does not happen. 1017 */ 1018 if (tickincr == 0) 1019 tickincr = 1; 1020 mtx_unlock_spin(&sched_lock); 1021} 1022 1023 1024/* 1025 * Scale the scheduling priority according to the "interactivity" of this 1026 * process. 1027 */ 1028static void 1029sched_priority(struct thread *td) 1030{ 1031 int score; 1032 int pri; 1033 1034 if (td->td_pri_class != PRI_TIMESHARE) 1035 return; 1036 /* 1037 * If the score is interactive we place the thread in the realtime 1038 * queue with a priority that is less than kernel and interrupt 1039 * priorities. These threads are not subject to nice restrictions. 1040 * 1041 * Scores greater than this are placed on the normal realtime queue 1042 * where the priority is partially decided by the most recent cpu 1043 * utilization and the rest is decided by nice value. 1044 */ 1045 score = sched_interact_score(td); 1046 if (score < sched_interact) { 1047 pri = PRI_MIN_REALTIME; 1048 pri += ((PRI_MAX_REALTIME - PRI_MIN_REALTIME) / sched_interact) 1049 * score; 1050 KASSERT(pri >= PRI_MIN_REALTIME && pri <= PRI_MAX_REALTIME, 1051 ("sched_priority: invalid interactive priority %d", pri)); 1052 } else { 1053 pri = SCHED_PRI_MIN; 1054 if (td->td_sched->ts_ticks) 1055 pri += SCHED_PRI_TICKS(td->td_sched); 1056 pri += SCHED_PRI_NICE(td->td_proc->p_nice); 1057 if (!(pri >= PRI_MIN_TIMESHARE && pri <= PRI_MAX_TIMESHARE)) { 1058 static int once = 1; 1059 if (once) { 1060 printf("sched_priority: invalid priority %d", 1061 pri); 1062 printf("nice %d, ticks %d ftick %d ltick %d tick pri %d\n", 1063 td->td_proc->p_nice, 1064 td->td_sched->ts_ticks, 1065 td->td_sched->ts_ftick, 1066 td->td_sched->ts_ltick, 1067 SCHED_PRI_TICKS(td->td_sched)); 1068 once = 0; 1069 } 1070 pri = min(max(pri, PRI_MIN_TIMESHARE), 1071 PRI_MAX_TIMESHARE); 1072 } 1073 } 1074 sched_user_prio(td, pri); 1075 1076 return; 1077} 1078 1079/* 1080 * This routine enforces a maximum limit on the amount of scheduling history 1081 * kept. It is called after either the slptime or runtime is adjusted. 1082 */ 1083static void 1084sched_interact_update(struct thread *td) 1085{ 1086 struct td_sched *ts; 1087 int sum; 1088 1089 ts = td->td_sched; 1090 sum = ts->skg_runtime + ts->skg_slptime; 1091 if (sum < SCHED_SLP_RUN_MAX) 1092 return; 1093 /* 1094 * This only happens from two places: 1095 * 1) We have added an unusual amount of run time from fork_exit. 1096 * 2) We have added an unusual amount of sleep time from sched_sleep(). 1097 */ 1098 if (sum > SCHED_SLP_RUN_MAX * 2) { 1099 if (ts->skg_runtime > ts->skg_slptime) { 1100 ts->skg_runtime = SCHED_SLP_RUN_MAX; 1101 ts->skg_slptime = 1; 1102 } else { 1103 ts->skg_slptime = SCHED_SLP_RUN_MAX; 1104 ts->skg_runtime = 1; 1105 } 1106 return; 1107 } 1108 /* 1109 * If we have exceeded by more than 1/5th then the algorithm below 1110 * will not bring us back into range. Dividing by two here forces 1111 * us into the range of [4/5 * SCHED_INTERACT_MAX, SCHED_INTERACT_MAX] 1112 */ 1113 if (sum > (SCHED_SLP_RUN_MAX / 5) * 6) { 1114 ts->skg_runtime /= 2; 1115 ts->skg_slptime /= 2; 1116 return; 1117 } 1118 ts->skg_runtime = (ts->skg_runtime / 5) * 4; 1119 ts->skg_slptime = (ts->skg_slptime / 5) * 4; 1120} 1121 1122static void 1123sched_interact_fork(struct thread *td) 1124{ 1125 int ratio; 1126 int sum; 1127 1128 sum = td->td_sched->skg_runtime + td->td_sched->skg_slptime; 1129 if (sum > SCHED_SLP_RUN_FORK) { 1130 ratio = sum / SCHED_SLP_RUN_FORK; 1131 td->td_sched->skg_runtime /= ratio; 1132 td->td_sched->skg_slptime /= ratio; 1133 } 1134} 1135 1136static int 1137sched_interact_score(struct thread *td) 1138{ 1139 int div; 1140 1141 if (td->td_sched->skg_runtime > td->td_sched->skg_slptime) { 1142 div = max(1, td->td_sched->skg_runtime / SCHED_INTERACT_HALF); 1143 return (SCHED_INTERACT_HALF + 1144 (SCHED_INTERACT_HALF - (td->td_sched->skg_slptime / div))); 1145 } if (td->td_sched->skg_slptime > td->td_sched->skg_runtime) { 1146 div = max(1, td->td_sched->skg_slptime / SCHED_INTERACT_HALF); 1147 return (td->td_sched->skg_runtime / div); 1148 } 1149 1150 /* 1151 * This can happen if slptime and runtime are 0. 1152 */ 1153 return (0); 1154 1155} 1156 1157/* 1158 * Called from proc0_init() to bootstrap the scheduler. 1159 */ 1160void 1161schedinit(void) 1162{ 1163 1164 /* 1165 * Set up the scheduler specific parts of proc0. 1166 */ 1167 proc0.p_sched = NULL; /* XXX */ 1168 thread0.td_sched = &td_sched0; 1169 td_sched0.ts_ltick = ticks; 1170 td_sched0.ts_ftick = ticks; 1171 td_sched0.ts_thread = &thread0; 1172 td_sched0.ts_state = TSS_THREAD; 1173} 1174 1175/* 1176 * This is only somewhat accurate since given many processes of the same 1177 * priority they will switch when their slices run out, which will be 1178 * at most sched_slice stathz ticks. 1179 */ 1180int 1181sched_rr_interval(void) 1182{ 1183 1184 /* Convert sched_slice to hz */ 1185 return (hz/(realstathz/sched_slice)); 1186} 1187 1188static void 1189sched_pctcpu_update(struct td_sched *ts) 1190{ 1191 1192 if (ts->ts_ticks == 0) 1193 return; 1194 if (ticks - (hz / 10) < ts->ts_ltick && 1195 SCHED_TICK_TOTAL(ts) < SCHED_TICK_MAX) 1196 return; 1197 /* 1198 * Adjust counters and watermark for pctcpu calc. 1199 */ 1200 if (ts->ts_ltick > ticks - SCHED_TICK_TARG) 1201 ts->ts_ticks = (ts->ts_ticks / (ticks - ts->ts_ftick)) * 1202 SCHED_TICK_TARG; 1203 else 1204 ts->ts_ticks = 0; 1205 ts->ts_ltick = ticks; 1206 ts->ts_ftick = ts->ts_ltick - SCHED_TICK_TARG; 1207} 1208 1209static void 1210sched_thread_priority(struct thread *td, u_char prio) 1211{ 1212 struct td_sched *ts; 1213 1214 CTR6(KTR_SCHED, "sched_prio: %p(%s) prio %d newprio %d by %p(%s)", 1215 td, td->td_proc->p_comm, td->td_priority, prio, curthread, 1216 curthread->td_proc->p_comm); 1217 ts = td->td_sched; 1218 mtx_assert(&sched_lock, MA_OWNED); 1219 if (td->td_priority == prio) 1220 return; 1221 1222 if (TD_ON_RUNQ(td) && prio < td->td_priority) { 1223 /* 1224 * If the priority has been elevated due to priority 1225 * propagation, we may have to move ourselves to a new 1226 * queue. This could be optimized to not re-add in some 1227 * cases. 1228 * 1229 * Hold this td_sched on this cpu so that sched_prio() doesn't 1230 * cause excessive migration. We only want migration to 1231 * happen as the result of a wakeup. 1232 */ 1233 ts->ts_flags |= TSF_HOLD; 1234 sched_rem(td); 1235 td->td_priority = prio; 1236 sched_add(td, SRQ_BORROWING); 1237 ts->ts_flags &= ~TSF_HOLD; 1238 } else 1239 td->td_priority = prio; 1240} 1241 1242/* 1243 * Update a thread's priority when it is lent another thread's 1244 * priority. 1245 */ 1246void 1247sched_lend_prio(struct thread *td, u_char prio) 1248{ 1249 1250 td->td_flags |= TDF_BORROWING; 1251 sched_thread_priority(td, prio); 1252} 1253 1254/* 1255 * Restore a thread's priority when priority propagation is 1256 * over. The prio argument is the minimum priority the thread 1257 * needs to have to satisfy other possible priority lending 1258 * requests. If the thread's regular priority is less 1259 * important than prio, the thread will keep a priority boost 1260 * of prio. 1261 */ 1262void 1263sched_unlend_prio(struct thread *td, u_char prio) 1264{ 1265 u_char base_pri; 1266 1267 if (td->td_base_pri >= PRI_MIN_TIMESHARE && 1268 td->td_base_pri <= PRI_MAX_TIMESHARE) 1269 base_pri = td->td_user_pri; 1270 else 1271 base_pri = td->td_base_pri; 1272 if (prio >= base_pri) { 1273 td->td_flags &= ~TDF_BORROWING; 1274 sched_thread_priority(td, base_pri); 1275 } else 1276 sched_lend_prio(td, prio); 1277} 1278 1279void 1280sched_prio(struct thread *td, u_char prio) 1281{ 1282 u_char oldprio; 1283 1284 /* First, update the base priority. */ 1285 td->td_base_pri = prio; 1286 1287 /* 1288 * If the thread is borrowing another thread's priority, don't 1289 * ever lower the priority. 1290 */ 1291 if (td->td_flags & TDF_BORROWING && td->td_priority < prio) 1292 return; 1293 1294 /* Change the real priority. */ 1295 oldprio = td->td_priority; 1296 sched_thread_priority(td, prio); 1297 1298 /* 1299 * If the thread is on a turnstile, then let the turnstile update 1300 * its state. 1301 */ 1302 if (TD_ON_LOCK(td) && oldprio != prio) 1303 turnstile_adjust(td, oldprio); 1304} 1305 1306void 1307sched_user_prio(struct thread *td, u_char prio) 1308{ 1309 u_char oldprio; 1310 1311 td->td_base_user_pri = prio; 1312 if (td->td_flags & TDF_UBORROWING && td->td_user_pri <= prio) 1313 return; 1314 oldprio = td->td_user_pri; 1315 td->td_user_pri = prio; 1316 1317 if (TD_ON_UPILOCK(td) && oldprio != prio) 1318 umtx_pi_adjust(td, oldprio); 1319} 1320 1321void 1322sched_lend_user_prio(struct thread *td, u_char prio) 1323{ 1324 u_char oldprio; 1325 1326 td->td_flags |= TDF_UBORROWING; 1327 1328 oldprio = td->td_user_pri; 1329 td->td_user_pri = prio; 1330 1331 if (TD_ON_UPILOCK(td) && oldprio != prio) 1332 umtx_pi_adjust(td, oldprio); 1333} 1334 1335void 1336sched_unlend_user_prio(struct thread *td, u_char prio) 1337{ 1338 u_char base_pri; 1339 1340 base_pri = td->td_base_user_pri; 1341 if (prio >= base_pri) { 1342 td->td_flags &= ~TDF_UBORROWING; 1343 sched_user_prio(td, base_pri); 1344 } else 1345 sched_lend_user_prio(td, prio); 1346} 1347 1348void 1349sched_switch(struct thread *td, struct thread *newtd, int flags) 1350{ 1351 struct tdq *tdq; 1352 struct td_sched *ts; 1353 1354 mtx_assert(&sched_lock, MA_OWNED); 1355 1356 tdq = TDQ_SELF(); 1357 ts = td->td_sched; 1358 td->td_lastcpu = td->td_oncpu; 1359 td->td_oncpu = NOCPU; 1360 td->td_flags &= ~TDF_NEEDRESCHED; 1361 td->td_owepreempt = 0; 1362 /* 1363 * If the thread has been assigned it may be in the process of switching 1364 * to the new cpu. This is the case in sched_bind(). 1365 */ 1366 if (td == PCPU_GET(idlethread)) { 1367 TD_SET_CAN_RUN(td); 1368 } else if ((ts->ts_flags & TSF_ASSIGNED) == 0) { 1369 /* We are ending our run so make our slot available again */ 1370 tdq_load_rem(tdq, ts); 1371 if (TD_IS_RUNNING(td)) { 1372 /* 1373 * Don't allow the thread to migrate 1374 * from a preemption. 1375 */ 1376 ts->ts_flags |= TSF_HOLD; 1377 setrunqueue(td, (flags & SW_PREEMPT) ? 1378 SRQ_OURSELF|SRQ_YIELDING|SRQ_PREEMPTED : 1379 SRQ_OURSELF|SRQ_YIELDING); 1380 ts->ts_flags &= ~TSF_HOLD; 1381 } 1382 } 1383 if (newtd != NULL) { 1384 /* 1385 * If we bring in a thread account for it as if it had been 1386 * added to the run queue and then chosen. 1387 */ 1388 newtd->td_sched->ts_flags |= TSF_DIDRUN; 1389 TD_SET_RUNNING(newtd); 1390 tdq_load_add(TDQ_SELF(), newtd->td_sched); 1391 } else 1392 newtd = choosethread(); 1393 if (td != newtd) { 1394#ifdef HWPMC_HOOKS 1395 if (PMC_PROC_IS_USING_PMCS(td->td_proc)) 1396 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT); 1397#endif 1398 1399 cpu_switch(td, newtd); 1400#ifdef HWPMC_HOOKS 1401 if (PMC_PROC_IS_USING_PMCS(td->td_proc)) 1402 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_IN); 1403#endif 1404 } 1405 sched_lock.mtx_lock = (uintptr_t)td; 1406 td->td_oncpu = PCPU_GET(cpuid); 1407} 1408 1409void 1410sched_nice(struct proc *p, int nice) 1411{ 1412 struct thread *td; 1413 1414 PROC_LOCK_ASSERT(p, MA_OWNED); 1415 mtx_assert(&sched_lock, MA_OWNED); 1416 1417 p->p_nice = nice; 1418 FOREACH_THREAD_IN_PROC(p, td) { 1419 sched_priority(td); 1420 sched_prio(td, td->td_base_user_pri); 1421 } 1422} 1423 1424void 1425sched_sleep(struct thread *td) 1426{ 1427 1428 mtx_assert(&sched_lock, MA_OWNED); 1429 1430 td->td_sched->ts_slptime = ticks; 1431} 1432 1433void 1434sched_wakeup(struct thread *td) 1435{ 1436 int slptime; 1437 1438 mtx_assert(&sched_lock, MA_OWNED); 1439 1440 /* 1441 * If we slept for more than a tick update our interactivity and 1442 * priority. 1443 */ 1444 slptime = td->td_sched->ts_slptime; 1445 td->td_sched->ts_slptime = 0; 1446 if (slptime && slptime != ticks) { 1447 int hzticks; 1448 1449 hzticks = (ticks - slptime) << SCHED_TICK_SHIFT; 1450 td->td_sched->skg_slptime += hzticks; 1451 sched_interact_update(td); 1452 sched_pctcpu_update(td->td_sched); 1453 sched_priority(td); 1454 } 1455 setrunqueue(td, SRQ_BORING); 1456} 1457 1458/* 1459 * Penalize the parent for creating a new child and initialize the child's 1460 * priority. 1461 */ 1462void 1463sched_fork(struct thread *td, struct thread *child) 1464{ 1465 mtx_assert(&sched_lock, MA_OWNED); 1466 sched_fork_thread(td, child); 1467 /* 1468 * Penalize the parent and child for forking. 1469 */ 1470 sched_interact_fork(child); 1471 sched_priority(child); 1472 td->td_sched->skg_runtime += tickincr; 1473 sched_interact_update(td); 1474 sched_priority(td); 1475} 1476 1477void 1478sched_fork_thread(struct thread *td, struct thread *child) 1479{ 1480 struct td_sched *ts; 1481 struct td_sched *ts2; 1482 1483 /* 1484 * Initialize child. 1485 */ 1486 sched_newthread(child); 1487 ts = td->td_sched; 1488 ts2 = child->td_sched; 1489 ts2->ts_cpu = ts->ts_cpu; 1490 ts2->ts_runq = NULL; 1491 /* 1492 * Grab our parents cpu estimation information and priority. 1493 */ 1494 ts2->ts_ticks = ts->ts_ticks; 1495 ts2->ts_ltick = ts->ts_ltick; 1496 ts2->ts_ftick = ts->ts_ftick; 1497 child->td_user_pri = td->td_user_pri; 1498 child->td_base_user_pri = td->td_base_user_pri; 1499 /* 1500 * And update interactivity score. 1501 */ 1502 ts2->skg_slptime = ts->skg_slptime; 1503 ts2->skg_runtime = ts->skg_runtime; 1504 ts2->ts_slice = 1; /* Attempt to quickly learn interactivity. */ 1505} 1506 1507void 1508sched_class(struct thread *td, int class) 1509{ 1510 struct tdq *tdq; 1511 struct td_sched *ts; 1512 int nclass; 1513 int oclass; 1514 1515 mtx_assert(&sched_lock, MA_OWNED); 1516 if (td->td_pri_class == class) 1517 return; 1518 1519 nclass = PRI_BASE(class); 1520 oclass = PRI_BASE(td->td_pri_class); 1521 ts = td->td_sched; 1522 if (ts->ts_state == TSS_ONRUNQ || td->td_state == TDS_RUNNING) { 1523 tdq = TDQ_CPU(ts->ts_cpu); 1524#ifdef SMP 1525 /* 1526 * On SMP if we're on the RUNQ we must adjust the transferable 1527 * count because could be changing to or from an interrupt 1528 * class. 1529 */ 1530 if (ts->ts_state == TSS_ONRUNQ) { 1531 if (THREAD_CAN_MIGRATE(ts->ts_thread)) { 1532 tdq->tdq_transferable--; 1533 tdq->tdq_group->tdg_transferable--; 1534 } 1535 if (THREAD_CAN_MIGRATE(ts->ts_thread)) { 1536 tdq->tdq_transferable++; 1537 tdq->tdq_group->tdg_transferable++; 1538 } 1539 } 1540#endif 1541 if (oclass == PRI_TIMESHARE) 1542 tdq->tdq_load_timeshare--; 1543 if (nclass == PRI_TIMESHARE) 1544 tdq->tdq_load_timeshare++; 1545 } 1546 1547 td->td_pri_class = class; 1548} 1549 1550/* 1551 * Return some of the child's priority and interactivity to the parent. 1552 */ 1553void 1554sched_exit(struct proc *p, struct thread *child) 1555{ 1556 struct thread *td; 1557 1558 CTR3(KTR_SCHED, "sched_exit: %p(%s) prio %d", 1559 child, child->td_proc->p_comm, child->td_priority); 1560 1561 td = FIRST_THREAD_IN_PROC(p); 1562 sched_exit_thread(td, child); 1563} 1564 1565void 1566sched_exit_thread(struct thread *td, struct thread *child) 1567{ 1568 1569 CTR3(KTR_SCHED, "sched_exit_thread: %p(%s) prio %d", 1570 child, child->td_proc->p_comm, child->td_priority); 1571 1572 tdq_load_rem(TDQ_CPU(child->td_sched->ts_cpu), child->td_sched); 1573#ifdef KSE 1574 /* 1575 * KSE forks and exits so often that this penalty causes short-lived 1576 * threads to always be non-interactive. This causes mozilla to 1577 * crawl under load. 1578 */ 1579 if ((td->td_pflags & TDP_SA) && td->td_proc == child->td_proc) 1580 return; 1581#endif 1582 /* 1583 * Give the child's runtime to the parent without returning the 1584 * sleep time as a penalty to the parent. This causes shells that 1585 * launch expensive things to mark their children as expensive. 1586 */ 1587 td->td_sched->skg_runtime += child->td_sched->skg_runtime; 1588 sched_interact_update(td); 1589 sched_priority(td); 1590} 1591 1592void 1593sched_userret(struct thread *td) 1594{ 1595 /* 1596 * XXX we cheat slightly on the locking here to avoid locking in 1597 * the usual case. Setting td_priority here is essentially an 1598 * incomplete workaround for not setting it properly elsewhere. 1599 * Now that some interrupt handlers are threads, not setting it 1600 * properly elsewhere can clobber it in the window between setting 1601 * it here and returning to user mode, so don't waste time setting 1602 * it perfectly here. 1603 */ 1604 KASSERT((td->td_flags & TDF_BORROWING) == 0, 1605 ("thread with borrowed priority returning to userland")); 1606 if (td->td_priority != td->td_user_pri) { 1607 mtx_lock_spin(&sched_lock); 1608 td->td_priority = td->td_user_pri; 1609 td->td_base_pri = td->td_user_pri; 1610 mtx_unlock_spin(&sched_lock); 1611 } 1612} 1613 1614void 1615sched_clock(struct thread *td) 1616{ 1617 struct tdq *tdq; 1618 struct td_sched *ts; 1619 1620 mtx_assert(&sched_lock, MA_OWNED); 1621#ifdef SMP 1622 sched_smp_tick(); 1623#endif 1624 tdq = TDQ_SELF(); 1625 /* 1626 * Advance the insert index once for each tick to ensure that all 1627 * threads get a chance to run. 1628 */ 1629 if (tdq->tdq_idx == tdq->tdq_ridx) { 1630 tdq->tdq_idx = (tdq->tdq_idx + 1) % RQ_NQS; 1631 if (TAILQ_EMPTY(&tdq->tdq_timeshare.rq_queues[tdq->tdq_ridx])) 1632 tdq->tdq_ridx = tdq->tdq_idx; 1633 } 1634 /* Adjust ticks for pctcpu */ 1635 ts = td->td_sched; 1636 ts->ts_ticks += tickincr; 1637 ts->ts_ltick = ticks; 1638 /* 1639 * Update if we've exceeded our desired tick threshhold by over one 1640 * second. 1641 */ 1642 if (ts->ts_ftick + SCHED_TICK_MAX < ts->ts_ltick) 1643 sched_pctcpu_update(ts); 1644 /* 1645 * We only do slicing code for TIMESHARE threads. 1646 */ 1647 if (td->td_pri_class != PRI_TIMESHARE) 1648 return; 1649 /* 1650 * We used a tick; charge it to the thread so that we can compute our 1651 * interactivity. 1652 */ 1653 td->td_sched->skg_runtime += tickincr; 1654 sched_interact_update(td); 1655 /* 1656 * We used up one time slice. 1657 */ 1658 if (--ts->ts_slice > 0) 1659 return; 1660 /* 1661 * We're out of time, recompute priorities and requeue. 1662 */ 1663 sched_priority(td); 1664 tdq_load_rem(tdq, ts); 1665 ts->ts_slice = sched_slice; 1666 tdq_load_add(tdq, ts); 1667 td->td_flags |= TDF_NEEDRESCHED; 1668} 1669 1670int 1671sched_runnable(void) 1672{ 1673 struct tdq *tdq; 1674 int load; 1675 1676 load = 1; 1677 1678 tdq = TDQ_SELF(); 1679#ifdef SMP 1680 if (tdq->tdq_assigned) { 1681 mtx_lock_spin(&sched_lock); 1682 tdq_assign(tdq); 1683 mtx_unlock_spin(&sched_lock); 1684 } 1685#endif 1686 if ((curthread->td_flags & TDF_IDLETD) != 0) { 1687 if (tdq->tdq_load > 0) 1688 goto out; 1689 } else 1690 if (tdq->tdq_load - 1 > 0) 1691 goto out; 1692 load = 0; 1693out: 1694 return (load); 1695} 1696 1697struct td_sched * 1698sched_choose(void) 1699{ 1700 struct tdq *tdq; 1701 struct td_sched *ts; 1702 1703 mtx_assert(&sched_lock, MA_OWNED); 1704 tdq = TDQ_SELF(); 1705#ifdef SMP 1706restart: 1707 if (tdq->tdq_assigned) 1708 tdq_assign(tdq); 1709#endif 1710 ts = tdq_choose(tdq); 1711 if (ts) { 1712#ifdef SMP 1713 if (ts->ts_thread->td_priority > PRI_MIN_IDLE) 1714 if (tdq_idled(tdq) == 0) 1715 goto restart; 1716#endif 1717 tdq_runq_rem(tdq, ts); 1718 ts->ts_state = TSS_THREAD; 1719 return (ts); 1720 } 1721#ifdef SMP 1722 if (tdq_idled(tdq) == 0) 1723 goto restart; 1724#endif 1725 return (NULL); 1726} 1727 1728void 1729sched_add(struct thread *td, int flags) 1730{ 1731 struct tdq *tdq; 1732 struct td_sched *ts; 1733 int preemptive; 1734 int canmigrate; 1735 int class; 1736 1737 CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)", 1738 td, td->td_proc->p_comm, td->td_priority, curthread, 1739 curthread->td_proc->p_comm); 1740 mtx_assert(&sched_lock, MA_OWNED); 1741 tdq = TDQ_SELF(); 1742 ts = td->td_sched; 1743 ts->ts_flags &= ~TSF_INTERNAL; 1744 class = PRI_BASE(td->td_pri_class); 1745 preemptive = !(flags & SRQ_YIELDING); 1746 canmigrate = 1; 1747#ifdef SMP 1748 if (ts->ts_flags & TSF_ASSIGNED) { 1749 if (ts->ts_flags & TSF_REMOVED) 1750 ts->ts_flags &= ~TSF_REMOVED; 1751 return; 1752 } 1753 canmigrate = THREAD_CAN_MIGRATE(td); 1754 /* 1755 * Don't migrate running threads here. Force the long term balancer 1756 * to do it. 1757 */ 1758 if (ts->ts_flags & TSF_HOLD) { 1759 ts->ts_flags &= ~TSF_HOLD; 1760 canmigrate = 0; 1761 } 1762#endif 1763 KASSERT(ts->ts_state != TSS_ONRUNQ, 1764 ("sched_add: thread %p (%s) already in run queue", td, 1765 td->td_proc->p_comm)); 1766 KASSERT(td->td_proc->p_sflag & PS_INMEM, 1767 ("sched_add: process swapped out")); 1768 KASSERT(ts->ts_runq == NULL, 1769 ("sched_add: thread %p is still assigned to a run queue", td)); 1770 /* 1771 * Set the slice and pick the run queue. 1772 */ 1773 if (ts->ts_slice == 0) 1774 ts->ts_slice = sched_slice; 1775 if (class == PRI_TIMESHARE) 1776 sched_priority(td); 1777 if (td->td_priority <= PRI_MAX_REALTIME) { 1778 ts->ts_runq = &tdq->tdq_realtime; 1779 /* 1780 * If the thread is not artificially pinned and it's in 1781 * the realtime queue we directly dispatch it on this cpu 1782 * for minimum latency. Interrupt handlers may also have 1783 * to complete on the cpu that dispatched them. 1784 */ 1785 if (td->td_pinned == 0 && class == PRI_ITHD) 1786 ts->ts_cpu = PCPU_GET(cpuid); 1787 } else if (td->td_priority <= PRI_MAX_TIMESHARE) 1788 ts->ts_runq = &tdq->tdq_timeshare; 1789 else 1790 ts->ts_runq = &tdq->tdq_idle; 1791 1792#ifdef SMP 1793 /* 1794 * If this thread is pinned or bound, notify the target cpu. 1795 */ 1796 if (!canmigrate && ts->ts_cpu != PCPU_GET(cpuid) ) { 1797 ts->ts_runq = NULL; 1798 tdq_notify(ts, ts->ts_cpu); 1799 return; 1800 } 1801 /* 1802 * If we had been idle, clear our bit in the group and potentially 1803 * the global bitmap. If not, see if we should transfer this thread. 1804 */ 1805 if ((class != PRI_IDLE && class != PRI_ITHD) && 1806 (tdq->tdq_group->tdg_idlemask & PCPU_GET(cpumask)) != 0) { 1807 /* 1808 * Check to see if our group is unidling, and if so, remove it 1809 * from the global idle mask. 1810 */ 1811 if (tdq->tdq_group->tdg_idlemask == 1812 tdq->tdq_group->tdg_cpumask) 1813 atomic_clear_int(&tdq_idle, tdq->tdq_group->tdg_mask); 1814 /* 1815 * Now remove ourselves from the group specific idle mask. 1816 */ 1817 tdq->tdq_group->tdg_idlemask &= ~PCPU_GET(cpumask); 1818 } else if (canmigrate && tdq->tdq_load > 1) 1819 if (tdq_transfer(tdq, ts, class)) 1820 return; 1821 ts->ts_cpu = PCPU_GET(cpuid); 1822#endif 1823 if (td->td_priority < curthread->td_priority) 1824 curthread->td_flags |= TDF_NEEDRESCHED; 1825 if (preemptive && maybe_preempt(td)) 1826 return; 1827 ts->ts_state = TSS_ONRUNQ; 1828 1829 tdq_runq_add(tdq, ts, flags); 1830 tdq_load_add(tdq, ts); 1831} 1832 1833void 1834sched_rem(struct thread *td) 1835{ 1836 struct tdq *tdq; 1837 struct td_sched *ts; 1838 1839 CTR5(KTR_SCHED, "sched_rem: %p(%s) prio %d by %p(%s)", 1840 td, td->td_proc->p_comm, td->td_priority, curthread, 1841 curthread->td_proc->p_comm); 1842 mtx_assert(&sched_lock, MA_OWNED); 1843 ts = td->td_sched; 1844 if (ts->ts_flags & TSF_ASSIGNED) { 1845 ts->ts_flags |= TSF_REMOVED; 1846 return; 1847 } 1848 KASSERT((ts->ts_state == TSS_ONRUNQ), 1849 ("sched_rem: thread not on run queue")); 1850 1851 ts->ts_state = TSS_THREAD; 1852 tdq = TDQ_CPU(ts->ts_cpu); 1853 tdq_runq_rem(tdq, ts); 1854 tdq_load_rem(tdq, ts); 1855} 1856 1857fixpt_t 1858sched_pctcpu(struct thread *td) 1859{ 1860 fixpt_t pctcpu; 1861 struct td_sched *ts; 1862 1863 pctcpu = 0; 1864 ts = td->td_sched; 1865 if (ts == NULL) 1866 return (0); 1867 1868 mtx_lock_spin(&sched_lock); 1869 if (ts->ts_ticks) { 1870 int rtick; 1871 1872 sched_pctcpu_update(ts); 1873 /* How many rtick per second ? */ 1874 rtick = min(SCHED_TICK_HZ(ts) / SCHED_TICK_SECS, hz); 1875 pctcpu = (FSCALE * ((FSCALE * rtick)/hz)) >> FSHIFT; 1876 } 1877 td->td_proc->p_swtime = ts->ts_ltick - ts->ts_ftick; 1878 mtx_unlock_spin(&sched_lock); 1879 1880 return (pctcpu); 1881} 1882 1883void 1884sched_bind(struct thread *td, int cpu) 1885{ 1886 struct td_sched *ts; 1887 1888 mtx_assert(&sched_lock, MA_OWNED); 1889 ts = td->td_sched; 1890 KASSERT((ts->ts_flags & TSF_BOUND) == 0, 1891 ("sched_bind: thread %p already bound.", td)); 1892 ts->ts_flags |= TSF_BOUND; 1893#ifdef SMP 1894 if (PCPU_GET(cpuid) == cpu) 1895 return; 1896 /* sched_rem without the runq_remove */ 1897 ts->ts_state = TSS_THREAD; 1898 tdq_load_rem(TDQ_CPU(ts->ts_cpu), ts); 1899 tdq_notify(ts, cpu); 1900 /* When we return from mi_switch we'll be on the correct cpu. */ 1901 mi_switch(SW_VOL, NULL); 1902 sched_pin(); 1903#endif 1904} 1905 1906void 1907sched_unbind(struct thread *td) 1908{ 1909 struct td_sched *ts; 1910 1911 mtx_assert(&sched_lock, MA_OWNED); 1912 ts = td->td_sched; 1913 KASSERT(ts->ts_flags & TSF_BOUND, 1914 ("sched_unbind: thread %p not bound.", td)); 1915 mtx_assert(&sched_lock, MA_OWNED); 1916 ts->ts_flags &= ~TSF_BOUND; 1917#ifdef SMP 1918 sched_unpin(); 1919#endif 1920} 1921 1922int 1923sched_is_bound(struct thread *td) 1924{ 1925 mtx_assert(&sched_lock, MA_OWNED); 1926 return (td->td_sched->ts_flags & TSF_BOUND); 1927} 1928 1929void 1930sched_relinquish(struct thread *td) 1931{ 1932 mtx_lock_spin(&sched_lock); 1933 if (td->td_pri_class == PRI_TIMESHARE) 1934 sched_prio(td, PRI_MAX_TIMESHARE); 1935 mi_switch(SW_VOL, NULL); 1936 mtx_unlock_spin(&sched_lock); 1937} 1938 1939int 1940sched_load(void) 1941{ 1942#ifdef SMP 1943 int total; 1944 int i; 1945 1946 total = 0; 1947 for (i = 0; i <= tdg_maxid; i++) 1948 total += TDQ_GROUP(i)->tdg_load; 1949 return (total); 1950#else 1951 return (TDQ_SELF()->tdq_sysload); 1952#endif 1953} 1954 1955int 1956sched_sizeof_proc(void) 1957{ 1958 return (sizeof(struct proc)); 1959} 1960 1961int 1962sched_sizeof_thread(void) 1963{ 1964 return (sizeof(struct thread) + sizeof(struct td_sched)); 1965} 1966 1967void 1968sched_tick(void) 1969{ 1970} 1971 1972static SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RW, 0, "Scheduler"); 1973SYSCTL_STRING(_kern_sched, OID_AUTO, name, CTLFLAG_RD, "ule", 0, 1974 "Scheduler name"); 1975SYSCTL_INT(_kern_sched, OID_AUTO, slice, CTLFLAG_RW, &sched_slice, 0, ""); 1976SYSCTL_INT(_kern_sched, OID_AUTO, interact, CTLFLAG_RW, &sched_interact, 0, ""); 1977SYSCTL_INT(_kern_sched, OID_AUTO, tickincr, CTLFLAG_RD, &tickincr, 0, ""); 1978SYSCTL_INT(_kern_sched, OID_AUTO, realstathz, CTLFLAG_RD, &realstathz, 0, ""); 1979SYSCTL_INT(_kern_sched, OID_AUTO, balance, CTLFLAG_RD, &sched_rebalance, 0, ""); 1980 1981/* ps compat */ 1982static fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */ 1983SYSCTL_INT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, ""); 1984 1985 1986#define KERN_SWITCH_INCLUDE 1 1987#include "kern/kern_switch.c" 1988