1 /*- 2 * Copyright (c) 2002-2005, 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("$FreeBSD$"); 29 30 #include "opt_hwpmc_hooks.h" 31 #include "opt_sched.h" 32 33 #define kse td_sched 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/kdb.h> 38 #include <sys/kernel.h> 39 #include <sys/ktr.h> 40 #include <sys/lock.h> 41 #include <sys/mutex.h> 42 #include <sys/proc.h> 43 #include <sys/resource.h> 44 #include <sys/resourcevar.h> 45 #include <sys/sched.h> 46 #include <sys/smp.h> 47 #include <sys/sx.h> 48 #include <sys/sysctl.h> 49 #include <sys/sysproto.h> 50 #include <sys/turnstile.h> 51 #include <sys/vmmeter.h> 52 #ifdef KTRACE 53 #include <sys/uio.h> 54 #include <sys/ktrace.h> 55 #endif 56 57 #ifdef HWPMC_HOOKS 58 #include <sys/pmckern.h> 59 #endif 60 61 #include <machine/cpu.h> 62 #include <machine/smp.h> 63 64 /* decay 95% of `p_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */ 65 /* XXX This is bogus compatability crap for ps */ 66 static fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */ 67 SYSCTL_INT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, ""); 68 69 static void sched_setup(void *dummy); 70 SYSINIT(sched_setup, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, sched_setup, NULL) 71 72 static SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RW, 0, "Scheduler"); 73 74 SYSCTL_STRING(_kern_sched, OID_AUTO, name, CTLFLAG_RD, "ule", 0, 75 "Scheduler name"); 76 77 static int slice_min = 1; 78 SYSCTL_INT(_kern_sched, OID_AUTO, slice_min, CTLFLAG_RW, &slice_min, 0, ""); 79 80 static int slice_max = 10; 81 SYSCTL_INT(_kern_sched, OID_AUTO, slice_max, CTLFLAG_RW, &slice_max, 0, ""); 82 83 int realstathz; 84 int tickincr = 1; 85 86 /* 87 * The following datastructures are allocated within their parent structure 88 * but are scheduler specific. 89 */ 90 /* 91 * The schedulable entity that can be given a context to run. A process may 92 * have several of these. 93 */ 94 struct kse { 95 TAILQ_ENTRY(kse) ke_procq; /* (j/z) Run queue. */ 96 int ke_flags; /* (j) KEF_* flags. */ 97 struct thread *ke_thread; /* (*) Active associated thread. */ 98 fixpt_t ke_pctcpu; /* (j) %cpu during p_swtime. */ 99 char ke_rqindex; /* (j) Run queue index. */ 100 enum { 101 KES_THREAD = 0x0, /* slaved to thread state */ 102 KES_ONRUNQ 103 } ke_state; /* (j) thread sched specific status. */ 104 int ke_slptime; 105 int ke_slice; 106 struct runq *ke_runq; 107 u_char ke_cpu; /* CPU that we have affinity for. */ 108 /* The following variables are only used for pctcpu calculation */ 109 int ke_ltick; /* Last tick that we were running on */ 110 int ke_ftick; /* First tick that we were running on */ 111 int ke_ticks; /* Tick count */ 112 113 }; 114 #define td_kse td_sched 115 #define td_slptime td_kse->ke_slptime 116 #define ke_proc ke_thread->td_proc 117 #define ke_ksegrp ke_thread->td_ksegrp 118 #define ke_assign ke_procq.tqe_next 119 /* flags kept in ke_flags */ 120 #define KEF_ASSIGNED 0x0001 /* Thread is being migrated. */ 121 #define KEF_BOUND 0x0002 /* Thread can not migrate. */ 122 #define KEF_XFERABLE 0x0004 /* Thread was added as transferable. */ 123 #define KEF_HOLD 0x0008 /* Thread is temporarily bound. */ 124 #define KEF_REMOVED 0x0010 /* Thread was removed while ASSIGNED */ 125 #define KEF_INTERNAL 0x0020 /* Thread added due to migration. */ 126 #define KEF_PREEMPTED 0x0040 /* Thread was preempted */ 127 #define KEF_DIDRUN 0x02000 /* Thread actually ran. */ 128 #define KEF_EXIT 0x04000 /* Thread is being killed. */ 129 130 struct kg_sched { 131 struct thread *skg_last_assigned; /* (j) Last thread assigned to */ 132 /* the system scheduler */ 133 int skg_slptime; /* Number of ticks we vol. slept */ 134 int skg_runtime; /* Number of ticks we were running */ 135 int skg_avail_opennings; /* (j) Num unfilled slots in group.*/ 136 int skg_concurrency; /* (j) Num threads requested in group.*/ 137 }; 138 #define kg_last_assigned kg_sched->skg_last_assigned 139 #define kg_avail_opennings kg_sched->skg_avail_opennings 140 #define kg_concurrency kg_sched->skg_concurrency 141 #define kg_runtime kg_sched->skg_runtime 142 #define kg_slptime kg_sched->skg_slptime 143 144 #define SLOT_RELEASE(kg) (kg)->kg_avail_opennings++ 145 #define SLOT_USE(kg) (kg)->kg_avail_opennings-- 146 147 static struct kse kse0; 148 static struct kg_sched kg_sched0; 149 150 /* 151 * The priority is primarily determined by the interactivity score. Thus, we 152 * give lower(better) priorities to kse groups that use less CPU. The nice 153 * value is then directly added to this to allow nice to have some effect 154 * on latency. 155 * 156 * PRI_RANGE: Total priority range for timeshare threads. 157 * PRI_NRESV: Number of nice values. 158 * PRI_BASE: The start of the dynamic range. 159 */ 160 #define SCHED_PRI_RANGE (PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE + 1) 161 #define SCHED_PRI_NRESV ((PRIO_MAX - PRIO_MIN) + 1) 162 #define SCHED_PRI_NHALF (SCHED_PRI_NRESV / 2) 163 #define SCHED_PRI_BASE (PRI_MIN_TIMESHARE) 164 #define SCHED_PRI_INTERACT(score) \ 165 ((score) * SCHED_PRI_RANGE / SCHED_INTERACT_MAX) 166 167 /* 168 * These determine the interactivity of a process. 169 * 170 * SLP_RUN_MAX: Maximum amount of sleep time + run time we'll accumulate 171 * before throttling back. 172 * SLP_RUN_FORK: Maximum slp+run time to inherit at fork time. 173 * INTERACT_MAX: Maximum interactivity value. Smaller is better. 174 * INTERACT_THRESH: Threshhold for placement on the current runq. 175 */ 176 #define SCHED_SLP_RUN_MAX ((hz * 5) << 10) 177 #define SCHED_SLP_RUN_FORK ((hz / 2) << 10) 178 #define SCHED_INTERACT_MAX (100) 179 #define SCHED_INTERACT_HALF (SCHED_INTERACT_MAX / 2) 180 #define SCHED_INTERACT_THRESH (30) 181 182 /* 183 * These parameters and macros determine the size of the time slice that is 184 * granted to each thread. 185 * 186 * SLICE_MIN: Minimum time slice granted, in units of ticks. 187 * SLICE_MAX: Maximum time slice granted. 188 * SLICE_RANGE: Range of available time slices scaled by hz. 189 * SLICE_SCALE: The number slices granted per val in the range of [0, max]. 190 * SLICE_NICE: Determine the amount of slice granted to a scaled nice. 191 * SLICE_NTHRESH: The nice cutoff point for slice assignment. 192 */ 193 #define SCHED_SLICE_MIN (slice_min) 194 #define SCHED_SLICE_MAX (slice_max) 195 #define SCHED_SLICE_INTERACTIVE (slice_max) 196 #define SCHED_SLICE_NTHRESH (SCHED_PRI_NHALF - 1) 197 #define SCHED_SLICE_RANGE (SCHED_SLICE_MAX - SCHED_SLICE_MIN + 1) 198 #define SCHED_SLICE_SCALE(val, max) (((val) * SCHED_SLICE_RANGE) / (max)) 199 #define SCHED_SLICE_NICE(nice) \ 200 (SCHED_SLICE_MAX - SCHED_SLICE_SCALE((nice), SCHED_SLICE_NTHRESH)) 201 202 /* 203 * This macro determines whether or not the thread belongs on the current or 204 * next run queue. 205 */ 206 #define SCHED_INTERACTIVE(kg) \ 207 (sched_interact_score(kg) < SCHED_INTERACT_THRESH) 208 #define SCHED_CURR(kg, ke) \ 209 ((ke->ke_thread->td_flags & TDF_BORROWING) || \ 210 (ke->ke_flags & KEF_PREEMPTED) || SCHED_INTERACTIVE(kg)) 211 212 /* 213 * Cpu percentage computation macros and defines. 214 * 215 * SCHED_CPU_TIME: Number of seconds to average the cpu usage across. 216 * SCHED_CPU_TICKS: Number of hz ticks to average the cpu usage across. 217 */ 218 219 #define SCHED_CPU_TIME 10 220 #define SCHED_CPU_TICKS (hz * SCHED_CPU_TIME) 221 222 /* 223 * kseq - per processor runqs and statistics. 224 */ 225 struct kseq { 226 struct runq ksq_idle; /* Queue of IDLE threads. */ 227 struct runq ksq_timeshare[2]; /* Run queues for !IDLE. */ 228 struct runq *ksq_next; /* Next timeshare queue. */ 229 struct runq *ksq_curr; /* Current queue. */ 230 int ksq_load_timeshare; /* Load for timeshare. */ 231 int ksq_load; /* Aggregate load. */ 232 short ksq_nice[SCHED_PRI_NRESV]; /* KSEs in each nice bin. */ 233 short ksq_nicemin; /* Least nice. */ 234 #ifdef SMP 235 int ksq_transferable; 236 LIST_ENTRY(kseq) ksq_siblings; /* Next in kseq group. */ 237 struct kseq_group *ksq_group; /* Our processor group. */ 238 volatile struct kse *ksq_assigned; /* assigned by another CPU. */ 239 #else 240 int ksq_sysload; /* For loadavg, !ITHD load. */ 241 #endif 242 }; 243 244 #ifdef SMP 245 /* 246 * kseq groups are groups of processors which can cheaply share threads. When 247 * one processor in the group goes idle it will check the runqs of the other 248 * processors in its group prior to halting and waiting for an interrupt. 249 * These groups are suitable for SMT (Symetric Multi-Threading) and not NUMA. 250 * In a numa environment we'd want an idle bitmap per group and a two tiered 251 * load balancer. 252 */ 253 struct kseq_group { 254 int ksg_cpus; /* Count of CPUs in this kseq group. */ 255 cpumask_t ksg_cpumask; /* Mask of cpus in this group. */ 256 cpumask_t ksg_idlemask; /* Idle cpus in this group. */ 257 cpumask_t ksg_mask; /* Bit mask for first cpu. */ 258 int ksg_load; /* Total load of this group. */ 259 int ksg_transferable; /* Transferable load of this group. */ 260 LIST_HEAD(, kseq) ksg_members; /* Linked list of all members. */ 261 }; 262 #endif 263 264 /* 265 * One kse queue per processor. 266 */ 267 #ifdef SMP 268 static cpumask_t kseq_idle; 269 static int ksg_maxid; 270 static struct kseq kseq_cpu[MAXCPU]; 271 static struct kseq_group kseq_groups[MAXCPU]; 272 static int bal_tick; 273 static int gbal_tick; 274 static int balance_groups; 275 276 #define KSEQ_SELF() (&kseq_cpu[PCPU_GET(cpuid)]) 277 #define KSEQ_CPU(x) (&kseq_cpu[(x)]) 278 #define KSEQ_ID(x) ((x) - kseq_cpu) 279 #define KSEQ_GROUP(x) (&kseq_groups[(x)]) 280 #else /* !SMP */ 281 static struct kseq kseq_cpu; 282 283 #define KSEQ_SELF() (&kseq_cpu) 284 #define KSEQ_CPU(x) (&kseq_cpu) 285 #endif 286 287 static void slot_fill(struct ksegrp *); 288 static struct kse *sched_choose(void); /* XXX Should be thread * */ 289 static void sched_slice(struct kse *); 290 static void sched_priority(struct ksegrp *); 291 static void sched_thread_priority(struct thread *, u_char); 292 static int sched_interact_score(struct ksegrp *); 293 static void sched_interact_update(struct ksegrp *); 294 static void sched_interact_fork(struct ksegrp *); 295 static void sched_pctcpu_update(struct kse *); 296 297 /* Operations on per processor queues */ 298 static struct kse * kseq_choose(struct kseq *); 299 static void kseq_setup(struct kseq *); 300 static void kseq_load_add(struct kseq *, struct kse *); 301 static void kseq_load_rem(struct kseq *, struct kse *); 302 static __inline void kseq_runq_add(struct kseq *, struct kse *, int); 303 static __inline void kseq_runq_rem(struct kseq *, struct kse *); 304 static void kseq_nice_add(struct kseq *, int); 305 static void kseq_nice_rem(struct kseq *, int); 306 void kseq_print(int cpu); 307 #ifdef SMP 308 static int kseq_transfer(struct kseq *, struct kse *, int); 309 static struct kse *runq_steal(struct runq *); 310 static void sched_balance(void); 311 static void sched_balance_groups(void); 312 static void sched_balance_group(struct kseq_group *); 313 static void sched_balance_pair(struct kseq *, struct kseq *); 314 static void kseq_move(struct kseq *, int); 315 static int kseq_idled(struct kseq *); 316 static void kseq_notify(struct kse *, int); 317 static void kseq_assign(struct kseq *); 318 static struct kse *kseq_steal(struct kseq *, int); 319 #define KSE_CAN_MIGRATE(ke) \ 320 ((ke)->ke_thread->td_pinned == 0 && ((ke)->ke_flags & KEF_BOUND) == 0) 321 #endif 322 323 void 324 kseq_print(int cpu) 325 { 326 struct kseq *kseq; 327 int i; 328 329 kseq = KSEQ_CPU(cpu); 330 331 printf("kseq:\n"); 332 printf("\tload: %d\n", kseq->ksq_load); 333 printf("\tload TIMESHARE: %d\n", kseq->ksq_load_timeshare); 334 #ifdef SMP 335 printf("\tload transferable: %d\n", kseq->ksq_transferable); 336 #endif 337 printf("\tnicemin:\t%d\n", kseq->ksq_nicemin); 338 printf("\tnice counts:\n"); 339 for (i = 0; i < SCHED_PRI_NRESV; i++) 340 if (kseq->ksq_nice[i]) 341 printf("\t\t%d = %d\n", 342 i - SCHED_PRI_NHALF, kseq->ksq_nice[i]); 343 } 344 345 static __inline void 346 kseq_runq_add(struct kseq *kseq, struct kse *ke, int flags) 347 { 348 #ifdef SMP 349 if (KSE_CAN_MIGRATE(ke)) { 350 kseq->ksq_transferable++; 351 kseq->ksq_group->ksg_transferable++; 352 ke->ke_flags |= KEF_XFERABLE; 353 } 354 #endif 355 if (ke->ke_flags & KEF_PREEMPTED) 356 flags |= SRQ_PREEMPTED; 357 runq_add(ke->ke_runq, ke, flags); 358 } 359 360 static __inline void 361 kseq_runq_rem(struct kseq *kseq, struct kse *ke) 362 { 363 #ifdef SMP 364 if (ke->ke_flags & KEF_XFERABLE) { 365 kseq->ksq_transferable--; 366 kseq->ksq_group->ksg_transferable--; 367 ke->ke_flags &= ~KEF_XFERABLE; 368 } 369 #endif 370 runq_remove(ke->ke_runq, ke); 371 } 372 373 static void 374 kseq_load_add(struct kseq *kseq, struct kse *ke) 375 { 376 int class; 377 mtx_assert(&sched_lock, MA_OWNED); 378 class = PRI_BASE(ke->ke_ksegrp->kg_pri_class); 379 if (class == PRI_TIMESHARE) 380 kseq->ksq_load_timeshare++; 381 kseq->ksq_load++; 382 CTR1(KTR_SCHED, "load: %d", kseq->ksq_load); 383 if (class != PRI_ITHD && (ke->ke_proc->p_flag & P_NOLOAD) == 0) 384 #ifdef SMP 385 kseq->ksq_group->ksg_load++; 386 #else 387 kseq->ksq_sysload++; 388 #endif 389 if (ke->ke_ksegrp->kg_pri_class == PRI_TIMESHARE) 390 kseq_nice_add(kseq, ke->ke_proc->p_nice); 391 } 392 393 static void 394 kseq_load_rem(struct kseq *kseq, struct kse *ke) 395 { 396 int class; 397 mtx_assert(&sched_lock, MA_OWNED); 398 class = PRI_BASE(ke->ke_ksegrp->kg_pri_class); 399 if (class == PRI_TIMESHARE) 400 kseq->ksq_load_timeshare--; 401 if (class != PRI_ITHD && (ke->ke_proc->p_flag & P_NOLOAD) == 0) 402 #ifdef SMP 403 kseq->ksq_group->ksg_load--; 404 #else 405 kseq->ksq_sysload--; 406 #endif 407 kseq->ksq_load--; 408 CTR1(KTR_SCHED, "load: %d", kseq->ksq_load); 409 ke->ke_runq = NULL; 410 if (ke->ke_ksegrp->kg_pri_class == PRI_TIMESHARE) 411 kseq_nice_rem(kseq, ke->ke_proc->p_nice); 412 } 413 414 static void 415 kseq_nice_add(struct kseq *kseq, int nice) 416 { 417 mtx_assert(&sched_lock, MA_OWNED); 418 /* Normalize to zero. */ 419 kseq->ksq_nice[nice + SCHED_PRI_NHALF]++; 420 if (nice < kseq->ksq_nicemin || kseq->ksq_load_timeshare == 1) 421 kseq->ksq_nicemin = nice; 422 } 423 424 static void 425 kseq_nice_rem(struct kseq *kseq, int nice) 426 { 427 int n; 428 429 mtx_assert(&sched_lock, MA_OWNED); 430 /* Normalize to zero. */ 431 n = nice + SCHED_PRI_NHALF; 432 kseq->ksq_nice[n]--; 433 KASSERT(kseq->ksq_nice[n] >= 0, ("Negative nice count.")); 434 435 /* 436 * If this wasn't the smallest nice value or there are more in 437 * this bucket we can just return. Otherwise we have to recalculate 438 * the smallest nice. 439 */ 440 if (nice != kseq->ksq_nicemin || 441 kseq->ksq_nice[n] != 0 || 442 kseq->ksq_load_timeshare == 0) 443 return; 444 445 for (; n < SCHED_PRI_NRESV; n++) 446 if (kseq->ksq_nice[n]) { 447 kseq->ksq_nicemin = n - SCHED_PRI_NHALF; 448 return; 449 } 450 } 451 452 #ifdef SMP 453 /* 454 * sched_balance is a simple CPU load balancing algorithm. It operates by 455 * finding the least loaded and most loaded cpu and equalizing their load 456 * by migrating some processes. 457 * 458 * Dealing only with two CPUs at a time has two advantages. Firstly, most 459 * installations will only have 2 cpus. Secondly, load balancing too much at 460 * once can have an unpleasant effect on the system. The scheduler rarely has 461 * enough information to make perfect decisions. So this algorithm chooses 462 * algorithm simplicity and more gradual effects on load in larger systems. 463 * 464 * It could be improved by considering the priorities and slices assigned to 465 * each task prior to balancing them. There are many pathological cases with 466 * any approach and so the semi random algorithm below may work as well as any. 467 * 468 */ 469 static void 470 sched_balance(void) 471 { 472 struct kseq_group *high; 473 struct kseq_group *low; 474 struct kseq_group *ksg; 475 int cnt; 476 int i; 477 478 bal_tick = ticks + (random() % (hz * 2)); 479 if (smp_started == 0) 480 return; 481 low = high = NULL; 482 i = random() % (ksg_maxid + 1); 483 for (cnt = 0; cnt <= ksg_maxid; cnt++) { 484 ksg = KSEQ_GROUP(i); 485 /* 486 * Find the CPU with the highest load that has some 487 * threads to transfer. 488 */ 489 if ((high == NULL || ksg->ksg_load > high->ksg_load) 490 && ksg->ksg_transferable) 491 high = ksg; 492 if (low == NULL || ksg->ksg_load < low->ksg_load) 493 low = ksg; 494 if (++i > ksg_maxid) 495 i = 0; 496 } 497 if (low != NULL && high != NULL && high != low) 498 sched_balance_pair(LIST_FIRST(&high->ksg_members), 499 LIST_FIRST(&low->ksg_members)); 500 } 501 502 static void 503 sched_balance_groups(void) 504 { 505 int i; 506 507 gbal_tick = ticks + (random() % (hz * 2)); 508 mtx_assert(&sched_lock, MA_OWNED); 509 if (smp_started) 510 for (i = 0; i <= ksg_maxid; i++) 511 sched_balance_group(KSEQ_GROUP(i)); 512 } 513 514 static void 515 sched_balance_group(struct kseq_group *ksg) 516 { 517 struct kseq *kseq; 518 struct kseq *high; 519 struct kseq *low; 520 int load; 521 522 if (ksg->ksg_transferable == 0) 523 return; 524 low = NULL; 525 high = NULL; 526 LIST_FOREACH(kseq, &ksg->ksg_members, ksq_siblings) { 527 load = kseq->ksq_load; 528 if (high == NULL || load > high->ksq_load) 529 high = kseq; 530 if (low == NULL || load < low->ksq_load) 531 low = kseq; 532 } 533 if (high != NULL && low != NULL && high != low) 534 sched_balance_pair(high, low); 535 } 536 537 static void 538 sched_balance_pair(struct kseq *high, struct kseq *low) 539 { 540 int transferable; 541 int high_load; 542 int low_load; 543 int move; 544 int diff; 545 int i; 546 547 /* 548 * If we're transfering within a group we have to use this specific 549 * kseq's transferable count, otherwise we can steal from other members 550 * of the group. 551 */ 552 if (high->ksq_group == low->ksq_group) { 553 transferable = high->ksq_transferable; 554 high_load = high->ksq_load; 555 low_load = low->ksq_load; 556 } else { 557 transferable = high->ksq_group->ksg_transferable; 558 high_load = high->ksq_group->ksg_load; 559 low_load = low->ksq_group->ksg_load; 560 } 561 if (transferable == 0) 562 return; 563 /* 564 * Determine what the imbalance is and then adjust that to how many 565 * kses we actually have to give up (transferable). 566 */ 567 diff = high_load - low_load; 568 move = diff / 2; 569 if (diff & 0x1) 570 move++; 571 move = min(move, transferable); 572 for (i = 0; i < move; i++) 573 kseq_move(high, KSEQ_ID(low)); 574 return; 575 } 576 577 static void 578 kseq_move(struct kseq *from, int cpu) 579 { 580 struct kseq *kseq; 581 struct kseq *to; 582 struct kse *ke; 583 584 kseq = from; 585 to = KSEQ_CPU(cpu); 586 ke = kseq_steal(kseq, 1); 587 if (ke == NULL) { 588 struct kseq_group *ksg; 589 590 ksg = kseq->ksq_group; 591 LIST_FOREACH(kseq, &ksg->ksg_members, ksq_siblings) { 592 if (kseq == from || kseq->ksq_transferable == 0) 593 continue; 594 ke = kseq_steal(kseq, 1); 595 break; 596 } 597 if (ke == NULL) 598 panic("kseq_move: No KSEs available with a " 599 "transferable count of %d\n", 600 ksg->ksg_transferable); 601 } 602 if (kseq == to) 603 return; 604 ke->ke_state = KES_THREAD; 605 kseq_runq_rem(kseq, ke); 606 kseq_load_rem(kseq, ke); 607 kseq_notify(ke, cpu); 608 } 609 610 static int 611 kseq_idled(struct kseq *kseq) 612 { 613 struct kseq_group *ksg; 614 struct kseq *steal; 615 struct kse *ke; 616 617 ksg = kseq->ksq_group; 618 /* 619 * If we're in a cpu group, try and steal kses from another cpu in 620 * the group before idling. 621 */ 622 if (ksg->ksg_cpus > 1 && ksg->ksg_transferable) { 623 LIST_FOREACH(steal, &ksg->ksg_members, ksq_siblings) { 624 if (steal == kseq || steal->ksq_transferable == 0) 625 continue; 626 ke = kseq_steal(steal, 0); 627 if (ke == NULL) 628 continue; 629 ke->ke_state = KES_THREAD; 630 kseq_runq_rem(steal, ke); 631 kseq_load_rem(steal, ke); 632 ke->ke_cpu = PCPU_GET(cpuid); 633 ke->ke_flags |= KEF_INTERNAL | KEF_HOLD; 634 sched_add(ke->ke_thread, SRQ_YIELDING); 635 return (0); 636 } 637 } 638 /* 639 * We only set the idled bit when all of the cpus in the group are 640 * idle. Otherwise we could get into a situation where a KSE bounces 641 * back and forth between two idle cores on seperate physical CPUs. 642 */ 643 ksg->ksg_idlemask |= PCPU_GET(cpumask); 644 if (ksg->ksg_idlemask != ksg->ksg_cpumask) 645 return (1); 646 atomic_set_int(&kseq_idle, ksg->ksg_mask); 647 return (1); 648 } 649 650 static void 651 kseq_assign(struct kseq *kseq) 652 { 653 struct kse *nke; 654 struct kse *ke; 655 656 do { 657 *(volatile struct kse **)&ke = kseq->ksq_assigned; 658 } while(!atomic_cmpset_ptr((volatile uintptr_t *)&kseq->ksq_assigned, 659 (uintptr_t)ke, (uintptr_t)NULL)); 660 for (; ke != NULL; ke = nke) { 661 nke = ke->ke_assign; 662 kseq->ksq_group->ksg_load--; 663 kseq->ksq_load--; 664 ke->ke_flags &= ~KEF_ASSIGNED; 665 if (ke->ke_flags & KEF_REMOVED) { 666 ke->ke_flags &= ~KEF_REMOVED; 667 continue; 668 } 669 ke->ke_flags |= KEF_INTERNAL | KEF_HOLD; 670 sched_add(ke->ke_thread, SRQ_YIELDING); 671 } 672 } 673 674 static void 675 kseq_notify(struct kse *ke, int cpu) 676 { 677 struct kseq *kseq; 678 struct thread *td; 679 struct pcpu *pcpu; 680 int class; 681 int prio; 682 683 kseq = KSEQ_CPU(cpu); 684 /* XXX */ 685 class = PRI_BASE(ke->ke_ksegrp->kg_pri_class); 686 if ((class == PRI_TIMESHARE || class == PRI_REALTIME) && 687 (kseq_idle & kseq->ksq_group->ksg_mask)) 688 atomic_clear_int(&kseq_idle, kseq->ksq_group->ksg_mask); 689 kseq->ksq_group->ksg_load++; 690 kseq->ksq_load++; 691 ke->ke_cpu = cpu; 692 ke->ke_flags |= KEF_ASSIGNED; 693 prio = ke->ke_thread->td_priority; 694 695 /* 696 * Place a KSE on another cpu's queue and force a resched. 697 */ 698 do { 699 *(volatile struct kse **)&ke->ke_assign = kseq->ksq_assigned; 700 } while(!atomic_cmpset_ptr((volatile uintptr_t *)&kseq->ksq_assigned, 701 (uintptr_t)ke->ke_assign, (uintptr_t)ke)); 702 /* 703 * Without sched_lock we could lose a race where we set NEEDRESCHED 704 * on a thread that is switched out before the IPI is delivered. This 705 * would lead us to miss the resched. This will be a problem once 706 * sched_lock is pushed down. 707 */ 708 pcpu = pcpu_find(cpu); 709 td = pcpu->pc_curthread; 710 if (ke->ke_thread->td_priority < td->td_priority || 711 td == pcpu->pc_idlethread) { 712 td->td_flags |= TDF_NEEDRESCHED; 713 ipi_selected(1 << cpu, IPI_AST); 714 } 715 } 716 717 static struct kse * 718 runq_steal(struct runq *rq) 719 { 720 struct rqhead *rqh; 721 struct rqbits *rqb; 722 struct kse *ke; 723 int word; 724 int bit; 725 726 mtx_assert(&sched_lock, MA_OWNED); 727 rqb = &rq->rq_status; 728 for (word = 0; word < RQB_LEN; word++) { 729 if (rqb->rqb_bits[word] == 0) 730 continue; 731 for (bit = 0; bit < RQB_BPW; bit++) { 732 if ((rqb->rqb_bits[word] & (1ul << bit)) == 0) 733 continue; 734 rqh = &rq->rq_queues[bit + (word << RQB_L2BPW)]; 735 TAILQ_FOREACH(ke, rqh, ke_procq) { 736 if (KSE_CAN_MIGRATE(ke)) 737 return (ke); 738 } 739 } 740 } 741 return (NULL); 742 } 743 744 static struct kse * 745 kseq_steal(struct kseq *kseq, int stealidle) 746 { 747 struct kse *ke; 748 749 /* 750 * Steal from next first to try to get a non-interactive task that 751 * may not have run for a while. 752 */ 753 if ((ke = runq_steal(kseq->ksq_next)) != NULL) 754 return (ke); 755 if ((ke = runq_steal(kseq->ksq_curr)) != NULL) 756 return (ke); 757 if (stealidle) 758 return (runq_steal(&kseq->ksq_idle)); 759 return (NULL); 760 } 761 762 int 763 kseq_transfer(struct kseq *kseq, struct kse *ke, int class) 764 { 765 struct kseq_group *nksg; 766 struct kseq_group *ksg; 767 struct kseq *old; 768 int cpu; 769 int idx; 770 771 if (smp_started == 0) 772 return (0); 773 cpu = 0; 774 /* 775 * If our load exceeds a certain threshold we should attempt to 776 * reassign this thread. The first candidate is the cpu that 777 * originally ran the thread. If it is idle, assign it there, 778 * otherwise, pick an idle cpu. 779 * 780 * The threshold at which we start to reassign kses has a large impact 781 * on the overall performance of the system. Tuned too high and 782 * some CPUs may idle. Too low and there will be excess migration 783 * and context switches. 784 */ 785 old = KSEQ_CPU(ke->ke_cpu); 786 nksg = old->ksq_group; 787 ksg = kseq->ksq_group; 788 if (kseq_idle) { 789 if (kseq_idle & nksg->ksg_mask) { 790 cpu = ffs(nksg->ksg_idlemask); 791 if (cpu) { 792 CTR2(KTR_SCHED, 793 "kseq_transfer: %p found old cpu %X " 794 "in idlemask.", ke, cpu); 795 goto migrate; 796 } 797 } 798 /* 799 * Multiple cpus could find this bit simultaneously 800 * but the race shouldn't be terrible. 801 */ 802 cpu = ffs(kseq_idle); 803 if (cpu) { 804 CTR2(KTR_SCHED, "kseq_transfer: %p found %X " 805 "in idlemask.", ke, cpu); 806 goto migrate; 807 } 808 } 809 idx = 0; 810 #if 0 811 if (old->ksq_load < kseq->ksq_load) { 812 cpu = ke->ke_cpu + 1; 813 CTR2(KTR_SCHED, "kseq_transfer: %p old cpu %X " 814 "load less than ours.", ke, cpu); 815 goto migrate; 816 } 817 /* 818 * No new CPU was found, look for one with less load. 819 */ 820 for (idx = 0; idx <= ksg_maxid; idx++) { 821 nksg = KSEQ_GROUP(idx); 822 if (nksg->ksg_load /*+ (nksg->ksg_cpus * 2)*/ < ksg->ksg_load) { 823 cpu = ffs(nksg->ksg_cpumask); 824 CTR2(KTR_SCHED, "kseq_transfer: %p cpu %X load less " 825 "than ours.", ke, cpu); 826 goto migrate; 827 } 828 } 829 #endif 830 /* 831 * If another cpu in this group has idled, assign a thread over 832 * to them after checking to see if there are idled groups. 833 */ 834 if (ksg->ksg_idlemask) { 835 cpu = ffs(ksg->ksg_idlemask); 836 if (cpu) { 837 CTR2(KTR_SCHED, "kseq_transfer: %p cpu %X idle in " 838 "group.", ke, cpu); 839 goto migrate; 840 } 841 } 842 return (0); 843 migrate: 844 /* 845 * Now that we've found an idle CPU, migrate the thread. 846 */ 847 cpu--; 848 ke->ke_runq = NULL; 849 kseq_notify(ke, cpu); 850 851 return (1); 852 } 853 854 #endif /* SMP */ 855 856 /* 857 * Pick the highest priority task we have and return it. 858 */ 859 860 static struct kse * 861 kseq_choose(struct kseq *kseq) 862 { 863 struct runq *swap; 864 struct kse *ke; 865 int nice; 866 867 mtx_assert(&sched_lock, MA_OWNED); 868 swap = NULL; 869 870 for (;;) { 871 ke = runq_choose(kseq->ksq_curr); 872 if (ke == NULL) { 873 /* 874 * We already swapped once and didn't get anywhere. 875 */ 876 if (swap) 877 break; 878 swap = kseq->ksq_curr; 879 kseq->ksq_curr = kseq->ksq_next; 880 kseq->ksq_next = swap; 881 continue; 882 } 883 /* 884 * If we encounter a slice of 0 the kse is in a 885 * TIMESHARE kse group and its nice was too far out 886 * of the range that receives slices. 887 */ 888 nice = ke->ke_proc->p_nice + (0 - kseq->ksq_nicemin); 889 if (ke->ke_slice == 0 || (nice > SCHED_SLICE_NTHRESH && 890 ke->ke_proc->p_nice != 0)) { 891 runq_remove(ke->ke_runq, ke); 892 sched_slice(ke); 893 ke->ke_runq = kseq->ksq_next; 894 runq_add(ke->ke_runq, ke, 0); 895 continue; 896 } 897 return (ke); 898 } 899 900 return (runq_choose(&kseq->ksq_idle)); 901 } 902 903 static void 904 kseq_setup(struct kseq *kseq) 905 { 906 runq_init(&kseq->ksq_timeshare[0]); 907 runq_init(&kseq->ksq_timeshare[1]); 908 runq_init(&kseq->ksq_idle); 909 kseq->ksq_curr = &kseq->ksq_timeshare[0]; 910 kseq->ksq_next = &kseq->ksq_timeshare[1]; 911 kseq->ksq_load = 0; 912 kseq->ksq_load_timeshare = 0; 913 } 914 915 static void 916 sched_setup(void *dummy) 917 { 918 #ifdef SMP 919 int i; 920 #endif 921 922 slice_min = (hz/100); /* 10ms */ 923 slice_max = (hz/7); /* ~140ms */ 924 925 #ifdef SMP 926 balance_groups = 0; 927 /* 928 * Initialize the kseqs. 929 */ 930 for (i = 0; i < MAXCPU; i++) { 931 struct kseq *ksq; 932 933 ksq = &kseq_cpu[i]; 934 ksq->ksq_assigned = NULL; 935 kseq_setup(&kseq_cpu[i]); 936 } 937 if (smp_topology == NULL) { 938 struct kseq_group *ksg; 939 struct kseq *ksq; 940 int cpus; 941 942 for (cpus = 0, i = 0; i < MAXCPU; i++) { 943 if (CPU_ABSENT(i)) 944 continue; 945 ksq = &kseq_cpu[cpus]; 946 ksg = &kseq_groups[cpus]; 947 /* 948 * Setup a kseq group with one member. 949 */ 950 ksq->ksq_transferable = 0; 951 ksq->ksq_group = ksg; 952 ksg->ksg_cpus = 1; 953 ksg->ksg_idlemask = 0; 954 ksg->ksg_cpumask = ksg->ksg_mask = 1 << i; 955 ksg->ksg_load = 0; 956 ksg->ksg_transferable = 0; 957 LIST_INIT(&ksg->ksg_members); 958 LIST_INSERT_HEAD(&ksg->ksg_members, ksq, ksq_siblings); 959 cpus++; 960 } 961 ksg_maxid = cpus - 1; 962 } else { 963 struct kseq_group *ksg; 964 struct cpu_group *cg; 965 int j; 966 967 for (i = 0; i < smp_topology->ct_count; i++) { 968 cg = &smp_topology->ct_group[i]; 969 ksg = &kseq_groups[i]; 970 /* 971 * Initialize the group. 972 */ 973 ksg->ksg_idlemask = 0; 974 ksg->ksg_load = 0; 975 ksg->ksg_transferable = 0; 976 ksg->ksg_cpus = cg->cg_count; 977 ksg->ksg_cpumask = cg->cg_mask; 978 LIST_INIT(&ksg->ksg_members); 979 /* 980 * Find all of the group members and add them. 981 */ 982 for (j = 0; j < MAXCPU; j++) { 983 if ((cg->cg_mask & (1 << j)) != 0) { 984 if (ksg->ksg_mask == 0) 985 ksg->ksg_mask = 1 << j; 986 kseq_cpu[j].ksq_transferable = 0; 987 kseq_cpu[j].ksq_group = ksg; 988 LIST_INSERT_HEAD(&ksg->ksg_members, 989 &kseq_cpu[j], ksq_siblings); 990 } 991 } 992 if (ksg->ksg_cpus > 1) 993 balance_groups = 1; 994 } 995 ksg_maxid = smp_topology->ct_count - 1; 996 } 997 /* 998 * Stagger the group and global load balancer so they do not 999 * interfere with each other. 1000 */ 1001 bal_tick = ticks + hz; 1002 if (balance_groups) 1003 gbal_tick = ticks + (hz / 2); 1004 #else 1005 kseq_setup(KSEQ_SELF()); 1006 #endif 1007 mtx_lock_spin(&sched_lock); 1008 kseq_load_add(KSEQ_SELF(), &kse0); 1009 mtx_unlock_spin(&sched_lock); 1010 } 1011 1012 /* 1013 * Scale the scheduling priority according to the "interactivity" of this 1014 * process. 1015 */ 1016 static void 1017 sched_priority(struct ksegrp *kg) 1018 { 1019 int pri; 1020 1021 if (kg->kg_pri_class != PRI_TIMESHARE) 1022 return; 1023 1024 pri = SCHED_PRI_INTERACT(sched_interact_score(kg)); 1025 pri += SCHED_PRI_BASE; 1026 pri += kg->kg_proc->p_nice; 1027 1028 if (pri > PRI_MAX_TIMESHARE) 1029 pri = PRI_MAX_TIMESHARE; 1030 else if (pri < PRI_MIN_TIMESHARE) 1031 pri = PRI_MIN_TIMESHARE; 1032 1033 kg->kg_user_pri = pri; 1034 1035 return; 1036 } 1037 1038 /* 1039 * Calculate a time slice based on the properties of the kseg and the runq 1040 * that we're on. This is only for PRI_TIMESHARE ksegrps. 1041 */ 1042 static void 1043 sched_slice(struct kse *ke) 1044 { 1045 struct kseq *kseq; 1046 struct ksegrp *kg; 1047 1048 kg = ke->ke_ksegrp; 1049 kseq = KSEQ_CPU(ke->ke_cpu); 1050 1051 if (ke->ke_thread->td_flags & TDF_BORROWING) { 1052 ke->ke_slice = SCHED_SLICE_MIN; 1053 return; 1054 } 1055 1056 /* 1057 * Rationale: 1058 * KSEs in interactive ksegs get a minimal slice so that we 1059 * quickly notice if it abuses its advantage. 1060 * 1061 * KSEs in non-interactive ksegs are assigned a slice that is 1062 * based on the ksegs nice value relative to the least nice kseg 1063 * on the run queue for this cpu. 1064 * 1065 * If the KSE is less nice than all others it gets the maximum 1066 * slice and other KSEs will adjust their slice relative to 1067 * this when they first expire. 1068 * 1069 * There is 20 point window that starts relative to the least 1070 * nice kse on the run queue. Slice size is determined by 1071 * the kse distance from the last nice ksegrp. 1072 * 1073 * If the kse is outside of the window it will get no slice 1074 * and will be reevaluated each time it is selected on the 1075 * run queue. The exception to this is nice 0 ksegs when 1076 * a nice -20 is running. They are always granted a minimum 1077 * slice. 1078 */ 1079 if (!SCHED_INTERACTIVE(kg)) { 1080 int nice; 1081 1082 nice = kg->kg_proc->p_nice + (0 - kseq->ksq_nicemin); 1083 if (kseq->ksq_load_timeshare == 0 || 1084 kg->kg_proc->p_nice < kseq->ksq_nicemin) 1085 ke->ke_slice = SCHED_SLICE_MAX; 1086 else if (nice <= SCHED_SLICE_NTHRESH) 1087 ke->ke_slice = SCHED_SLICE_NICE(nice); 1088 else if (kg->kg_proc->p_nice == 0) 1089 ke->ke_slice = SCHED_SLICE_MIN; 1090 else 1091 ke->ke_slice = 0; 1092 } else 1093 ke->ke_slice = SCHED_SLICE_INTERACTIVE; 1094 1095 return; 1096 } 1097 1098 /* 1099 * This routine enforces a maximum limit on the amount of scheduling history 1100 * kept. It is called after either the slptime or runtime is adjusted. 1101 * This routine will not operate correctly when slp or run times have been 1102 * adjusted to more than double their maximum. 1103 */ 1104 static void 1105 sched_interact_update(struct ksegrp *kg) 1106 { 1107 int sum; 1108 1109 sum = kg->kg_runtime + kg->kg_slptime; 1110 if (sum < SCHED_SLP_RUN_MAX) 1111 return; 1112 /* 1113 * If we have exceeded by more than 1/5th then the algorithm below 1114 * will not bring us back into range. Dividing by two here forces 1115 * us into the range of [4/5 * SCHED_INTERACT_MAX, SCHED_INTERACT_MAX] 1116 */ 1117 if (sum > (SCHED_SLP_RUN_MAX / 5) * 6) { 1118 kg->kg_runtime /= 2; 1119 kg->kg_slptime /= 2; 1120 return; 1121 } 1122 kg->kg_runtime = (kg->kg_runtime / 5) * 4; 1123 kg->kg_slptime = (kg->kg_slptime / 5) * 4; 1124 } 1125 1126 static void 1127 sched_interact_fork(struct ksegrp *kg) 1128 { 1129 int ratio; 1130 int sum; 1131 1132 sum = kg->kg_runtime + kg->kg_slptime; 1133 if (sum > SCHED_SLP_RUN_FORK) { 1134 ratio = sum / SCHED_SLP_RUN_FORK; 1135 kg->kg_runtime /= ratio; 1136 kg->kg_slptime /= ratio; 1137 } 1138 } 1139 1140 static int 1141 sched_interact_score(struct ksegrp *kg) 1142 { 1143 int div; 1144 1145 if (kg->kg_runtime > kg->kg_slptime) { 1146 div = max(1, kg->kg_runtime / SCHED_INTERACT_HALF); 1147 return (SCHED_INTERACT_HALF + 1148 (SCHED_INTERACT_HALF - (kg->kg_slptime / div))); 1149 } if (kg->kg_slptime > kg->kg_runtime) { 1150 div = max(1, kg->kg_slptime / SCHED_INTERACT_HALF); 1151 return (kg->kg_runtime / div); 1152 } 1153 1154 /* 1155 * This can happen if slptime and runtime are 0. 1156 */ 1157 return (0); 1158 1159 } 1160 1161 /* 1162 * Very early in the boot some setup of scheduler-specific 1163 * parts of proc0 and of soem scheduler resources needs to be done. 1164 * Called from: 1165 * proc0_init() 1166 */ 1167 void 1168 schedinit(void) 1169 { 1170 /* 1171 * Set up the scheduler specific parts of proc0. 1172 */ 1173 proc0.p_sched = NULL; /* XXX */ 1174 ksegrp0.kg_sched = &kg_sched0; 1175 thread0.td_sched = &kse0; 1176 kse0.ke_thread = &thread0; 1177 kse0.ke_state = KES_THREAD; 1178 kg_sched0.skg_concurrency = 1; 1179 kg_sched0.skg_avail_opennings = 0; /* we are already running */ 1180 } 1181 1182 /* 1183 * This is only somewhat accurate since given many processes of the same 1184 * priority they will switch when their slices run out, which will be 1185 * at most SCHED_SLICE_MAX. 1186 */ 1187 int 1188 sched_rr_interval(void) 1189 { 1190 return (SCHED_SLICE_MAX); 1191 } 1192 1193 static void 1194 sched_pctcpu_update(struct kse *ke) 1195 { 1196 /* 1197 * Adjust counters and watermark for pctcpu calc. 1198 */ 1199 if (ke->ke_ltick > ticks - SCHED_CPU_TICKS) { 1200 /* 1201 * Shift the tick count out so that the divide doesn't 1202 * round away our results. 1203 */ 1204 ke->ke_ticks <<= 10; 1205 ke->ke_ticks = (ke->ke_ticks / (ticks - ke->ke_ftick)) * 1206 SCHED_CPU_TICKS; 1207 ke->ke_ticks >>= 10; 1208 } else 1209 ke->ke_ticks = 0; 1210 ke->ke_ltick = ticks; 1211 ke->ke_ftick = ke->ke_ltick - SCHED_CPU_TICKS; 1212 } 1213 1214 void 1215 sched_thread_priority(struct thread *td, u_char prio) 1216 { 1217 struct kse *ke; 1218 1219 CTR6(KTR_SCHED, "sched_prio: %p(%s) prio %d newprio %d by %p(%s)", 1220 td, td->td_proc->p_comm, td->td_priority, prio, curthread, 1221 curthread->td_proc->p_comm); 1222 ke = td->td_kse; 1223 mtx_assert(&sched_lock, MA_OWNED); 1224 if (td->td_priority == prio) 1225 return; 1226 if (TD_ON_RUNQ(td)) { 1227 /* 1228 * If the priority has been elevated due to priority 1229 * propagation, we may have to move ourselves to a new 1230 * queue. We still call adjustrunqueue below in case kse 1231 * needs to fix things up. 1232 */ 1233 if (prio < td->td_priority && ke->ke_runq != NULL && 1234 (ke->ke_flags & KEF_ASSIGNED) == 0 && 1235 ke->ke_runq != KSEQ_CPU(ke->ke_cpu)->ksq_curr) { 1236 runq_remove(ke->ke_runq, ke); 1237 ke->ke_runq = KSEQ_CPU(ke->ke_cpu)->ksq_curr; 1238 runq_add(ke->ke_runq, ke, 0); 1239 } 1240 /* 1241 * Hold this kse on this cpu so that sched_prio() doesn't 1242 * cause excessive migration. We only want migration to 1243 * happen as the result of a wakeup. 1244 */ 1245 ke->ke_flags |= KEF_HOLD; 1246 adjustrunqueue(td, prio); 1247 ke->ke_flags &= ~KEF_HOLD; 1248 } else 1249 td->td_priority = prio; 1250 } 1251 1252 /* 1253 * Update a thread's priority when it is lent another thread's 1254 * priority. 1255 */ 1256 void 1257 sched_lend_prio(struct thread *td, u_char prio) 1258 { 1259 1260 td->td_flags |= TDF_BORROWING; 1261 sched_thread_priority(td, prio); 1262 } 1263 1264 /* 1265 * Restore a thread's priority when priority propagation is 1266 * over. The prio argument is the minimum priority the thread 1267 * needs to have to satisfy other possible priority lending 1268 * requests. If the thread's regular priority is less 1269 * important than prio, the thread will keep a priority boost 1270 * of prio. 1271 */ 1272 void 1273 sched_unlend_prio(struct thread *td, u_char prio) 1274 { 1275 u_char base_pri; 1276 1277 if (td->td_base_pri >= PRI_MIN_TIMESHARE && 1278 td->td_base_pri <= PRI_MAX_TIMESHARE) 1279 base_pri = td->td_ksegrp->kg_user_pri; 1280 else 1281 base_pri = td->td_base_pri; 1282 if (prio >= base_pri) { 1283 td->td_flags &= ~TDF_BORROWING; 1284 sched_thread_priority(td, base_pri); 1285 } else 1286 sched_lend_prio(td, prio); 1287 } 1288 1289 void 1290 sched_prio(struct thread *td, u_char prio) 1291 { 1292 u_char oldprio; 1293 1294 /* First, update the base priority. */ 1295 td->td_base_pri = prio; 1296 1297 /* 1298 * If the thread is borrowing another thread's priority, don't 1299 * ever lower the priority. 1300 */ 1301 if (td->td_flags & TDF_BORROWING && td->td_priority < prio) 1302 return; 1303 1304 /* Change the real priority. */ 1305 oldprio = td->td_priority; 1306 sched_thread_priority(td, prio); 1307 1308 /* 1309 * If the thread is on a turnstile, then let the turnstile update 1310 * its state. 1311 */ 1312 if (TD_ON_LOCK(td) && oldprio != prio) 1313 turnstile_adjust(td, oldprio); 1314 } 1315 1316 void 1317 sched_switch(struct thread *td, struct thread *newtd, int flags) 1318 { 1319 struct kseq *ksq; 1320 struct kse *ke; 1321 1322 mtx_assert(&sched_lock, MA_OWNED); 1323 1324 ke = td->td_kse; 1325 ksq = KSEQ_SELF(); 1326 1327 td->td_lastcpu = td->td_oncpu; 1328 td->td_oncpu = NOCPU; 1329 td->td_flags &= ~TDF_NEEDRESCHED; 1330 td->td_owepreempt = 0; 1331 1332 /* 1333 * If the KSE has been assigned it may be in the process of switching 1334 * to the new cpu. This is the case in sched_bind(). 1335 */ 1336 if (td == PCPU_GET(idlethread)) { 1337 TD_SET_CAN_RUN(td); 1338 } else if ((ke->ke_flags & KEF_ASSIGNED) == 0) { 1339 /* We are ending our run so make our slot available again */ 1340 SLOT_RELEASE(td->td_ksegrp); 1341 kseq_load_rem(ksq, ke); 1342 if (TD_IS_RUNNING(td)) { 1343 /* 1344 * Don't allow the thread to migrate 1345 * from a preemption. 1346 */ 1347 ke->ke_flags |= KEF_HOLD; 1348 setrunqueue(td, (flags & SW_PREEMPT) ? 1349 SRQ_OURSELF|SRQ_YIELDING|SRQ_PREEMPTED : 1350 SRQ_OURSELF|SRQ_YIELDING); 1351 ke->ke_flags &= ~KEF_HOLD; 1352 } else if ((td->td_proc->p_flag & P_HADTHREADS) && 1353 (newtd == NULL || newtd->td_ksegrp != td->td_ksegrp)) 1354 /* 1355 * We will not be on the run queue. 1356 * So we must be sleeping or similar. 1357 * Don't use the slot if we will need it 1358 * for newtd. 1359 */ 1360 slot_fill(td->td_ksegrp); 1361 } 1362 if (newtd != NULL) { 1363 /* 1364 * If we bring in a thread account for it as if it had been 1365 * added to the run queue and then chosen. 1366 */ 1367 newtd->td_kse->ke_flags |= KEF_DIDRUN; 1368 newtd->td_kse->ke_runq = ksq->ksq_curr; 1369 TD_SET_RUNNING(newtd); 1370 kseq_load_add(KSEQ_SELF(), newtd->td_kse); 1371 /* 1372 * XXX When we preempt, we've already consumed a slot because 1373 * we got here through sched_add(). However, newtd can come 1374 * from thread_switchout() which can't SLOT_USE() because 1375 * the SLOT code is scheduler dependent. We must use the 1376 * slot here otherwise. 1377 */ 1378 if ((flags & SW_PREEMPT) == 0) 1379 SLOT_USE(newtd->td_ksegrp); 1380 } else 1381 newtd = choosethread(); 1382 if (td != newtd) { 1383 #ifdef HWPMC_HOOKS 1384 if (PMC_PROC_IS_USING_PMCS(td->td_proc)) 1385 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT); 1386 #endif 1387 cpu_switch(td, newtd); 1388 #ifdef HWPMC_HOOKS 1389 if (PMC_PROC_IS_USING_PMCS(td->td_proc)) 1390 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_IN); 1391 #endif 1392 } 1393 1394 sched_lock.mtx_lock = (uintptr_t)td; 1395 1396 td->td_oncpu = PCPU_GET(cpuid); 1397 } 1398 1399 void 1400 sched_nice(struct proc *p, int nice) 1401 { 1402 struct ksegrp *kg; 1403 struct kse *ke; 1404 struct thread *td; 1405 struct kseq *kseq; 1406 1407 PROC_LOCK_ASSERT(p, MA_OWNED); 1408 mtx_assert(&sched_lock, MA_OWNED); 1409 /* 1410 * We need to adjust the nice counts for running KSEs. 1411 */ 1412 FOREACH_KSEGRP_IN_PROC(p, kg) { 1413 if (kg->kg_pri_class == PRI_TIMESHARE) { 1414 FOREACH_THREAD_IN_GROUP(kg, td) { 1415 ke = td->td_kse; 1416 if (ke->ke_runq == NULL) 1417 continue; 1418 kseq = KSEQ_CPU(ke->ke_cpu); 1419 kseq_nice_rem(kseq, p->p_nice); 1420 kseq_nice_add(kseq, nice); 1421 } 1422 } 1423 } 1424 p->p_nice = nice; 1425 FOREACH_KSEGRP_IN_PROC(p, kg) { 1426 sched_priority(kg); 1427 FOREACH_THREAD_IN_GROUP(kg, td) 1428 td->td_flags |= TDF_NEEDRESCHED; 1429 } 1430 } 1431 1432 void 1433 sched_sleep(struct thread *td) 1434 { 1435 mtx_assert(&sched_lock, MA_OWNED); 1436 1437 td->td_slptime = ticks; 1438 } 1439 1440 void 1441 sched_wakeup(struct thread *td) 1442 { 1443 mtx_assert(&sched_lock, MA_OWNED); 1444 1445 /* 1446 * Let the kseg know how long we slept for. This is because process 1447 * interactivity behavior is modeled in the kseg. 1448 */ 1449 if (td->td_slptime) { 1450 struct ksegrp *kg; 1451 int hzticks; 1452 1453 kg = td->td_ksegrp; 1454 hzticks = (ticks - td->td_slptime) << 10; 1455 if (hzticks >= SCHED_SLP_RUN_MAX) { 1456 kg->kg_slptime = SCHED_SLP_RUN_MAX; 1457 kg->kg_runtime = 1; 1458 } else { 1459 kg->kg_slptime += hzticks; 1460 sched_interact_update(kg); 1461 } 1462 sched_priority(kg); 1463 sched_slice(td->td_kse); 1464 td->td_slptime = 0; 1465 } 1466 setrunqueue(td, SRQ_BORING); 1467 } 1468 1469 /* 1470 * Penalize the parent for creating a new child and initialize the child's 1471 * priority. 1472 */ 1473 void 1474 sched_fork(struct thread *td, struct thread *childtd) 1475 { 1476 1477 mtx_assert(&sched_lock, MA_OWNED); 1478 1479 sched_fork_ksegrp(td, childtd->td_ksegrp); 1480 sched_fork_thread(td, childtd); 1481 } 1482 1483 void 1484 sched_fork_ksegrp(struct thread *td, struct ksegrp *child) 1485 { 1486 struct ksegrp *kg = td->td_ksegrp; 1487 mtx_assert(&sched_lock, MA_OWNED); 1488 1489 child->kg_slptime = kg->kg_slptime; 1490 child->kg_runtime = kg->kg_runtime; 1491 child->kg_user_pri = kg->kg_user_pri; 1492 sched_interact_fork(child); 1493 kg->kg_runtime += tickincr << 10; 1494 sched_interact_update(kg); 1495 } 1496 1497 void 1498 sched_fork_thread(struct thread *td, struct thread *child) 1499 { 1500 struct kse *ke; 1501 struct kse *ke2; 1502 1503 sched_newthread(child); 1504 ke = td->td_kse; 1505 ke2 = child->td_kse; 1506 ke2->ke_slice = 1; /* Attempt to quickly learn interactivity. */ 1507 ke2->ke_cpu = ke->ke_cpu; 1508 ke2->ke_runq = NULL; 1509 1510 /* Grab our parents cpu estimation information. */ 1511 ke2->ke_ticks = ke->ke_ticks; 1512 ke2->ke_ltick = ke->ke_ltick; 1513 ke2->ke_ftick = ke->ke_ftick; 1514 } 1515 1516 void 1517 sched_class(struct ksegrp *kg, int class) 1518 { 1519 struct kseq *kseq; 1520 struct kse *ke; 1521 struct thread *td; 1522 int nclass; 1523 int oclass; 1524 1525 mtx_assert(&sched_lock, MA_OWNED); 1526 if (kg->kg_pri_class == class) 1527 return; 1528 1529 nclass = PRI_BASE(class); 1530 oclass = PRI_BASE(kg->kg_pri_class); 1531 FOREACH_THREAD_IN_GROUP(kg, td) { 1532 ke = td->td_kse; 1533 if ((ke->ke_state != KES_ONRUNQ && 1534 ke->ke_state != KES_THREAD) || ke->ke_runq == NULL) 1535 continue; 1536 kseq = KSEQ_CPU(ke->ke_cpu); 1537 1538 #ifdef SMP 1539 /* 1540 * On SMP if we're on the RUNQ we must adjust the transferable 1541 * count because could be changing to or from an interrupt 1542 * class. 1543 */ 1544 if (ke->ke_state == KES_ONRUNQ) { 1545 if (KSE_CAN_MIGRATE(ke)) { 1546 kseq->ksq_transferable--; 1547 kseq->ksq_group->ksg_transferable--; 1548 } 1549 if (KSE_CAN_MIGRATE(ke)) { 1550 kseq->ksq_transferable++; 1551 kseq->ksq_group->ksg_transferable++; 1552 } 1553 } 1554 #endif 1555 if (oclass == PRI_TIMESHARE) { 1556 kseq->ksq_load_timeshare--; 1557 kseq_nice_rem(kseq, kg->kg_proc->p_nice); 1558 } 1559 if (nclass == PRI_TIMESHARE) { 1560 kseq->ksq_load_timeshare++; 1561 kseq_nice_add(kseq, kg->kg_proc->p_nice); 1562 } 1563 } 1564 1565 kg->kg_pri_class = class; 1566 } 1567 1568 /* 1569 * Return some of the child's priority and interactivity to the parent. 1570 */ 1571 void 1572 sched_exit(struct proc *p, struct thread *childtd) 1573 { 1574 mtx_assert(&sched_lock, MA_OWNED); 1575 sched_exit_ksegrp(FIRST_KSEGRP_IN_PROC(p), childtd); 1576 sched_exit_thread(NULL, childtd); 1577 } 1578 1579 void 1580 sched_exit_ksegrp(struct ksegrp *kg, struct thread *td) 1581 { 1582 /* kg->kg_slptime += td->td_ksegrp->kg_slptime; */ 1583 kg->kg_runtime += td->td_ksegrp->kg_runtime; 1584 sched_interact_update(kg); 1585 } 1586 1587 void 1588 sched_exit_thread(struct thread *td, struct thread *childtd) 1589 { 1590 CTR3(KTR_SCHED, "sched_exit_thread: %p(%s) prio %d", 1591 childtd, childtd->td_proc->p_comm, childtd->td_priority); 1592 kseq_load_rem(KSEQ_CPU(childtd->td_kse->ke_cpu), childtd->td_kse); 1593 } 1594 1595 void 1596 sched_clock(struct thread *td) 1597 { 1598 struct kseq *kseq; 1599 struct ksegrp *kg; 1600 struct kse *ke; 1601 1602 mtx_assert(&sched_lock, MA_OWNED); 1603 kseq = KSEQ_SELF(); 1604 #ifdef SMP 1605 if (ticks >= bal_tick) 1606 sched_balance(); 1607 if (ticks >= gbal_tick && balance_groups) 1608 sched_balance_groups(); 1609 /* 1610 * We could have been assigned a non real-time thread without an 1611 * IPI. 1612 */ 1613 if (kseq->ksq_assigned) 1614 kseq_assign(kseq); /* Potentially sets NEEDRESCHED */ 1615 #endif 1616 /* 1617 * sched_setup() apparently happens prior to stathz being set. We 1618 * need to resolve the timers earlier in the boot so we can avoid 1619 * calculating this here. 1620 */ 1621 if (realstathz == 0) { 1622 realstathz = stathz ? stathz : hz; 1623 tickincr = hz / realstathz; 1624 /* 1625 * XXX This does not work for values of stathz that are much 1626 * larger than hz. 1627 */ 1628 if (tickincr == 0) 1629 tickincr = 1; 1630 } 1631 1632 ke = td->td_kse; 1633 kg = ke->ke_ksegrp; 1634 1635 /* Adjust ticks for pctcpu */ 1636 ke->ke_ticks++; 1637 ke->ke_ltick = ticks; 1638 1639 /* Go up to one second beyond our max and then trim back down */ 1640 if (ke->ke_ftick + SCHED_CPU_TICKS + hz < ke->ke_ltick) 1641 sched_pctcpu_update(ke); 1642 1643 if (td->td_flags & TDF_IDLETD) 1644 return; 1645 /* 1646 * We only do slicing code for TIMESHARE ksegrps. 1647 */ 1648 if (kg->kg_pri_class != PRI_TIMESHARE) 1649 return; 1650 /* 1651 * We used a tick charge it to the ksegrp so that we can compute our 1652 * interactivity. 1653 */ 1654 kg->kg_runtime += tickincr << 10; 1655 sched_interact_update(kg); 1656 1657 /* 1658 * We used up one time slice. 1659 */ 1660 if (--ke->ke_slice > 0) 1661 return; 1662 /* 1663 * We're out of time, recompute priorities and requeue. 1664 */ 1665 kseq_load_rem(kseq, ke); 1666 sched_priority(kg); 1667 sched_slice(ke); 1668 if (SCHED_CURR(kg, ke)) 1669 ke->ke_runq = kseq->ksq_curr; 1670 else 1671 ke->ke_runq = kseq->ksq_next; 1672 kseq_load_add(kseq, ke); 1673 td->td_flags |= TDF_NEEDRESCHED; 1674 } 1675 1676 int 1677 sched_runnable(void) 1678 { 1679 struct kseq *kseq; 1680 int load; 1681 1682 load = 1; 1683 1684 kseq = KSEQ_SELF(); 1685 #ifdef SMP 1686 if (kseq->ksq_assigned) { 1687 mtx_lock_spin(&sched_lock); 1688 kseq_assign(kseq); 1689 mtx_unlock_spin(&sched_lock); 1690 } 1691 #endif 1692 if ((curthread->td_flags & TDF_IDLETD) != 0) { 1693 if (kseq->ksq_load > 0) 1694 goto out; 1695 } else 1696 if (kseq->ksq_load - 1 > 0) 1697 goto out; 1698 load = 0; 1699 out: 1700 return (load); 1701 } 1702 1703 void 1704 sched_userret(struct thread *td) 1705 { 1706 struct ksegrp *kg; 1707 1708 KASSERT((td->td_flags & TDF_BORROWING) == 0, 1709 ("thread with borrowed priority returning to userland")); 1710 kg = td->td_ksegrp; 1711 if (td->td_priority != kg->kg_user_pri) { 1712 mtx_lock_spin(&sched_lock); 1713 td->td_priority = kg->kg_user_pri; 1714 td->td_base_pri = kg->kg_user_pri; 1715 mtx_unlock_spin(&sched_lock); 1716 } 1717 } 1718 1719 struct kse * 1720 sched_choose(void) 1721 { 1722 struct kseq *kseq; 1723 struct kse *ke; 1724 1725 mtx_assert(&sched_lock, MA_OWNED); 1726 kseq = KSEQ_SELF(); 1727 #ifdef SMP 1728 restart: 1729 if (kseq->ksq_assigned) 1730 kseq_assign(kseq); 1731 #endif 1732 ke = kseq_choose(kseq); 1733 if (ke) { 1734 #ifdef SMP 1735 if (ke->ke_ksegrp->kg_pri_class == PRI_IDLE) 1736 if (kseq_idled(kseq) == 0) 1737 goto restart; 1738 #endif 1739 kseq_runq_rem(kseq, ke); 1740 ke->ke_state = KES_THREAD; 1741 ke->ke_flags &= ~KEF_PREEMPTED; 1742 return (ke); 1743 } 1744 #ifdef SMP 1745 if (kseq_idled(kseq) == 0) 1746 goto restart; 1747 #endif 1748 return (NULL); 1749 } 1750 1751 void 1752 sched_add(struct thread *td, int flags) 1753 { 1754 struct kseq *kseq; 1755 struct ksegrp *kg; 1756 struct kse *ke; 1757 int preemptive; 1758 int canmigrate; 1759 int class; 1760 1761 CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)", 1762 td, td->td_proc->p_comm, td->td_priority, curthread, 1763 curthread->td_proc->p_comm); 1764 mtx_assert(&sched_lock, MA_OWNED); 1765 ke = td->td_kse; 1766 kg = td->td_ksegrp; 1767 canmigrate = 1; 1768 preemptive = !(flags & SRQ_YIELDING); 1769 class = PRI_BASE(kg->kg_pri_class); 1770 kseq = KSEQ_SELF(); 1771 if ((ke->ke_flags & KEF_INTERNAL) == 0) 1772 SLOT_USE(td->td_ksegrp); 1773 ke->ke_flags &= ~KEF_INTERNAL; 1774 #ifdef SMP 1775 if (ke->ke_flags & KEF_ASSIGNED) { 1776 if (ke->ke_flags & KEF_REMOVED) 1777 ke->ke_flags &= ~KEF_REMOVED; 1778 return; 1779 } 1780 canmigrate = KSE_CAN_MIGRATE(ke); 1781 /* 1782 * Don't migrate running threads here. Force the long term balancer 1783 * to do it. 1784 */ 1785 if (ke->ke_flags & KEF_HOLD) { 1786 ke->ke_flags &= ~KEF_HOLD; 1787 canmigrate = 0; 1788 } 1789 #endif 1790 KASSERT(ke->ke_state != KES_ONRUNQ, 1791 ("sched_add: kse %p (%s) already in run queue", ke, 1792 ke->ke_proc->p_comm)); 1793 KASSERT(ke->ke_proc->p_sflag & PS_INMEM, 1794 ("sched_add: process swapped out")); 1795 KASSERT(ke->ke_runq == NULL, 1796 ("sched_add: KSE %p is still assigned to a run queue", ke)); 1797 if (flags & SRQ_PREEMPTED) 1798 ke->ke_flags |= KEF_PREEMPTED; 1799 switch (class) { 1800 case PRI_ITHD: 1801 case PRI_REALTIME: 1802 ke->ke_runq = kseq->ksq_curr; 1803 ke->ke_slice = SCHED_SLICE_MAX; 1804 if (canmigrate) 1805 ke->ke_cpu = PCPU_GET(cpuid); 1806 break; 1807 case PRI_TIMESHARE: 1808 if (SCHED_CURR(kg, ke)) 1809 ke->ke_runq = kseq->ksq_curr; 1810 else 1811 ke->ke_runq = kseq->ksq_next; 1812 break; 1813 case PRI_IDLE: 1814 /* 1815 * This is for priority prop. 1816 */ 1817 if (ke->ke_thread->td_priority < PRI_MIN_IDLE) 1818 ke->ke_runq = kseq->ksq_curr; 1819 else 1820 ke->ke_runq = &kseq->ksq_idle; 1821 ke->ke_slice = SCHED_SLICE_MIN; 1822 break; 1823 default: 1824 panic("Unknown pri class."); 1825 break; 1826 } 1827 #ifdef SMP 1828 /* 1829 * If this thread is pinned or bound, notify the target cpu. 1830 */ 1831 if (!canmigrate && ke->ke_cpu != PCPU_GET(cpuid) ) { 1832 ke->ke_runq = NULL; 1833 kseq_notify(ke, ke->ke_cpu); 1834 return; 1835 } 1836 /* 1837 * If we had been idle, clear our bit in the group and potentially 1838 * the global bitmap. If not, see if we should transfer this thread. 1839 */ 1840 if ((class == PRI_TIMESHARE || class == PRI_REALTIME) && 1841 (kseq->ksq_group->ksg_idlemask & PCPU_GET(cpumask)) != 0) { 1842 /* 1843 * Check to see if our group is unidling, and if so, remove it 1844 * from the global idle mask. 1845 */ 1846 if (kseq->ksq_group->ksg_idlemask == 1847 kseq->ksq_group->ksg_cpumask) 1848 atomic_clear_int(&kseq_idle, kseq->ksq_group->ksg_mask); 1849 /* 1850 * Now remove ourselves from the group specific idle mask. 1851 */ 1852 kseq->ksq_group->ksg_idlemask &= ~PCPU_GET(cpumask); 1853 } else if (canmigrate && kseq->ksq_load > 1 && class != PRI_ITHD) 1854 if (kseq_transfer(kseq, ke, class)) 1855 return; 1856 ke->ke_cpu = PCPU_GET(cpuid); 1857 #endif 1858 if (td->td_priority < curthread->td_priority && 1859 ke->ke_runq == kseq->ksq_curr) 1860 curthread->td_flags |= TDF_NEEDRESCHED; 1861 if (preemptive && maybe_preempt(td)) 1862 return; 1863 ke->ke_state = KES_ONRUNQ; 1864 1865 kseq_runq_add(kseq, ke, flags); 1866 kseq_load_add(kseq, ke); 1867 } 1868 1869 void 1870 sched_rem(struct thread *td) 1871 { 1872 struct kseq *kseq; 1873 struct kse *ke; 1874 1875 CTR5(KTR_SCHED, "sched_rem: %p(%s) prio %d by %p(%s)", 1876 td, td->td_proc->p_comm, td->td_priority, curthread, 1877 curthread->td_proc->p_comm); 1878 mtx_assert(&sched_lock, MA_OWNED); 1879 ke = td->td_kse; 1880 SLOT_RELEASE(td->td_ksegrp); 1881 ke->ke_flags &= ~KEF_PREEMPTED; 1882 if (ke->ke_flags & KEF_ASSIGNED) { 1883 ke->ke_flags |= KEF_REMOVED; 1884 return; 1885 } 1886 KASSERT((ke->ke_state == KES_ONRUNQ), 1887 ("sched_rem: KSE not on run queue")); 1888 1889 ke->ke_state = KES_THREAD; 1890 kseq = KSEQ_CPU(ke->ke_cpu); 1891 kseq_runq_rem(kseq, ke); 1892 kseq_load_rem(kseq, ke); 1893 } 1894 1895 fixpt_t 1896 sched_pctcpu(struct thread *td) 1897 { 1898 fixpt_t pctcpu; 1899 struct kse *ke; 1900 1901 pctcpu = 0; 1902 ke = td->td_kse; 1903 if (ke == NULL) 1904 return (0); 1905 1906 mtx_lock_spin(&sched_lock); 1907 if (ke->ke_ticks) { 1908 int rtick; 1909 1910 /* 1911 * Don't update more frequently than twice a second. Allowing 1912 * this causes the cpu usage to decay away too quickly due to 1913 * rounding errors. 1914 */ 1915 if (ke->ke_ftick + SCHED_CPU_TICKS < ke->ke_ltick || 1916 ke->ke_ltick < (ticks - (hz / 2))) 1917 sched_pctcpu_update(ke); 1918 /* How many rtick per second ? */ 1919 rtick = min(ke->ke_ticks / SCHED_CPU_TIME, SCHED_CPU_TICKS); 1920 pctcpu = (FSCALE * ((FSCALE * rtick)/realstathz)) >> FSHIFT; 1921 } 1922 1923 ke->ke_proc->p_swtime = ke->ke_ltick - ke->ke_ftick; 1924 mtx_unlock_spin(&sched_lock); 1925 1926 return (pctcpu); 1927 } 1928 1929 void 1930 sched_bind(struct thread *td, int cpu) 1931 { 1932 struct kse *ke; 1933 1934 mtx_assert(&sched_lock, MA_OWNED); 1935 ke = td->td_kse; 1936 ke->ke_flags |= KEF_BOUND; 1937 #ifdef SMP 1938 if (PCPU_GET(cpuid) == cpu) 1939 return; 1940 /* sched_rem without the runq_remove */ 1941 ke->ke_state = KES_THREAD; 1942 kseq_load_rem(KSEQ_CPU(ke->ke_cpu), ke); 1943 kseq_notify(ke, cpu); 1944 /* When we return from mi_switch we'll be on the correct cpu. */ 1945 mi_switch(SW_VOL, NULL); 1946 #endif 1947 } 1948 1949 void 1950 sched_unbind(struct thread *td) 1951 { 1952 mtx_assert(&sched_lock, MA_OWNED); 1953 td->td_kse->ke_flags &= ~KEF_BOUND; 1954 } 1955 1956 int 1957 sched_is_bound(struct thread *td) 1958 { 1959 mtx_assert(&sched_lock, MA_OWNED); 1960 return (td->td_kse->ke_flags & KEF_BOUND); 1961 } 1962 1963 int 1964 sched_load(void) 1965 { 1966 #ifdef SMP 1967 int total; 1968 int i; 1969 1970 total = 0; 1971 for (i = 0; i <= ksg_maxid; i++) 1972 total += KSEQ_GROUP(i)->ksg_load; 1973 return (total); 1974 #else 1975 return (KSEQ_SELF()->ksq_sysload); 1976 #endif 1977 } 1978 1979 int 1980 sched_sizeof_ksegrp(void) 1981 { 1982 return (sizeof(struct ksegrp) + sizeof(struct kg_sched)); 1983 } 1984 1985 int 1986 sched_sizeof_proc(void) 1987 { 1988 return (sizeof(struct proc)); 1989 } 1990 1991 int 1992 sched_sizeof_thread(void) 1993 { 1994 return (sizeof(struct thread) + sizeof(struct td_sched)); 1995 } 1996 #define KERN_SWITCH_INCLUDE 1 1997 #include "kern/kern_switch.c" 1998