FreeBSD/Linux Kernel Cross Reference
sys/kern/sched_4bsd.c
1 /*-
2 * Copyright (c) 1982, 1986, 1990, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD: releng/6.4/sys/kern/sched_4bsd.c 179975 2008-06-24 19:55:22Z jhb $");
37
38 #include "opt_hwpmc_hooks.h"
39
40 #define kse td_sched
41
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/kernel.h>
45 #include <sys/ktr.h>
46 #include <sys/lock.h>
47 #include <sys/kthread.h>
48 #include <sys/mutex.h>
49 #include <sys/proc.h>
50 #include <sys/resourcevar.h>
51 #include <sys/sched.h>
52 #include <sys/smp.h>
53 #include <sys/sysctl.h>
54 #include <sys/sx.h>
55 #include <sys/turnstile.h>
56 #include <machine/smp.h>
57
58 #ifdef HWPMC_HOOKS
59 #include <sys/pmckern.h>
60 #endif
61
62 /*
63 * INVERSE_ESTCPU_WEIGHT is only suitable for statclock() frequencies in
64 * the range 100-256 Hz (approximately).
65 */
66 #define ESTCPULIM(e) \
67 min((e), INVERSE_ESTCPU_WEIGHT * (NICE_WEIGHT * (PRIO_MAX - PRIO_MIN) - \
68 RQ_PPQ) + INVERSE_ESTCPU_WEIGHT - 1)
69 #ifdef SMP
70 #define INVERSE_ESTCPU_WEIGHT (8 * smp_cpus)
71 #else
72 #define INVERSE_ESTCPU_WEIGHT 8 /* 1 / (priorities per estcpu level). */
73 #endif
74 #define NICE_WEIGHT 1 /* Priorities per nice level. */
75
76 /*
77 * The schedulable entity that can be given a context to run.
78 * A process may have several of these. Probably one per processor
79 * but posibly a few more. In this universe they are grouped
80 * with a KSEG that contains the priority and niceness
81 * for the group.
82 */
83 struct kse {
84 TAILQ_ENTRY(kse) ke_procq; /* (j/z) Run queue. */
85 struct thread *ke_thread; /* (*) Active associated thread. */
86 fixpt_t ke_pctcpu; /* (j) %cpu during p_swtime. */
87 char ke_rqindex; /* (j) Run queue index. */
88 enum {
89 KES_THREAD = 0x0, /* slaved to thread state */
90 KES_ONRUNQ
91 } ke_state; /* (j) KSE status. */
92 int ke_cpticks; /* (j) Ticks of cpu time. */
93 struct runq *ke_runq; /* runq the kse is currently on */
94 };
95
96 #define ke_proc ke_thread->td_proc
97 #define ke_ksegrp ke_thread->td_ksegrp
98
99 #define td_kse td_sched
100
101 /* flags kept in td_flags */
102 #define TDF_DIDRUN TDF_SCHED0 /* KSE actually ran. */
103 #define TDF_EXIT TDF_SCHED1 /* KSE is being killed. */
104 #define TDF_BOUND TDF_SCHED2
105
106 #define ke_flags ke_thread->td_flags
107 #define KEF_DIDRUN TDF_DIDRUN /* KSE actually ran. */
108 #define KEF_EXIT TDF_EXIT /* KSE is being killed. */
109 #define KEF_BOUND TDF_BOUND /* stuck to one CPU */
110
111 #define SKE_RUNQ_PCPU(ke) \
112 ((ke)->ke_runq != 0 && (ke)->ke_runq != &runq)
113
114 struct kg_sched {
115 struct thread *skg_last_assigned; /* (j) Last thread assigned to */
116 /* the system scheduler. */
117 int skg_avail_opennings; /* (j) Num KSEs requested in group. */
118 int skg_concurrency; /* (j) Num KSEs requested in group. */
119 };
120 #define kg_last_assigned kg_sched->skg_last_assigned
121 #define kg_avail_opennings kg_sched->skg_avail_opennings
122 #define kg_concurrency kg_sched->skg_concurrency
123
124 #define SLOT_RELEASE(kg) \
125 do { \
126 kg->kg_avail_opennings++; \
127 CTR3(KTR_RUNQ, "kg %p(%d) Slot released (->%d)", \
128 kg, \
129 kg->kg_concurrency, \
130 kg->kg_avail_opennings); \
131 /* KASSERT((kg->kg_avail_opennings <= kg->kg_concurrency), \
132 ("slots out of whack"));*/ \
133 } while (0)
134
135 #define SLOT_USE(kg) \
136 do { \
137 kg->kg_avail_opennings--; \
138 CTR3(KTR_RUNQ, "kg %p(%d) Slot used (->%d)", \
139 kg, \
140 kg->kg_concurrency, \
141 kg->kg_avail_opennings); \
142 /* KASSERT((kg->kg_avail_opennings >= 0), \
143 ("slots out of whack"));*/ \
144 } while (0)
145
146 /*
147 * KSE_CAN_MIGRATE macro returns true if the kse can migrate between
148 * cpus.
149 */
150 #define KSE_CAN_MIGRATE(ke) \
151 ((ke)->ke_thread->td_pinned == 0 && ((ke)->ke_flags & KEF_BOUND) == 0)
152
153 static struct kse kse0;
154 static struct kg_sched kg_sched0;
155
156 static int sched_tdcnt; /* Total runnable threads in the system. */
157 static int sched_quantum; /* Roundrobin scheduling quantum in ticks. */
158 #define SCHED_QUANTUM (hz / 10) /* Default sched quantum */
159
160 static void slot_fill(struct ksegrp *kg);
161 static struct kse *sched_choose(void); /* XXX Should be thread * */
162
163 static void setup_runqs(void);
164 static void schedcpu(void);
165 static void schedcpu_thread(void);
166 static void sched_priority(struct thread *td, u_char prio);
167 static void sched_setup(void *dummy);
168 static void maybe_resched(struct thread *td);
169 static void updatepri(struct ksegrp *kg);
170 static void resetpriority(struct ksegrp *kg);
171 static void resetpriority_thread(struct thread *td, struct ksegrp *kg);
172 #ifdef SMP
173 static int forward_wakeup(int cpunum);
174 #endif
175
176 static struct kproc_desc sched_kp = {
177 "schedcpu",
178 schedcpu_thread,
179 NULL
180 };
181 SYSINIT(schedcpu, SI_SUB_RUN_SCHEDULER, SI_ORDER_FIRST, kproc_start, &sched_kp)
182 SYSINIT(sched_setup, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, sched_setup, NULL)
183
184 /*
185 * Global run queue.
186 */
187 static struct runq runq;
188
189 #ifdef SMP
190 /*
191 * Per-CPU run queues
192 */
193 static struct runq runq_pcpu[MAXCPU];
194 #endif
195
196 static void
197 setup_runqs(void)
198 {
199 #ifdef SMP
200 int i;
201
202 for (i = 0; i < MAXCPU; ++i)
203 runq_init(&runq_pcpu[i]);
204 #endif
205
206 runq_init(&runq);
207 }
208
209 static int
210 sysctl_kern_quantum(SYSCTL_HANDLER_ARGS)
211 {
212 int error, new_val;
213
214 new_val = sched_quantum * tick;
215 error = sysctl_handle_int(oidp, &new_val, 0, req);
216 if (error != 0 || req->newptr == NULL)
217 return (error);
218 if (new_val < tick)
219 return (EINVAL);
220 sched_quantum = new_val / tick;
221 hogticks = 2 * sched_quantum;
222 return (0);
223 }
224
225 SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RD, 0, "Scheduler");
226
227 SYSCTL_STRING(_kern_sched, OID_AUTO, name, CTLFLAG_RD, "4BSD", 0,
228 "Scheduler name");
229
230 SYSCTL_PROC(_kern_sched, OID_AUTO, quantum, CTLTYPE_INT | CTLFLAG_RW,
231 0, sizeof sched_quantum, sysctl_kern_quantum, "I",
232 "Roundrobin scheduling quantum in microseconds");
233
234 #ifdef SMP
235 /* Enable forwarding of wakeups to all other cpus */
236 SYSCTL_NODE(_kern_sched, OID_AUTO, ipiwakeup, CTLFLAG_RD, NULL, "Kernel SMP");
237
238 static int forward_wakeup_enabled = 1;
239 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, enabled, CTLFLAG_RW,
240 &forward_wakeup_enabled, 0,
241 "Forwarding of wakeup to idle CPUs");
242
243 static int forward_wakeups_requested = 0;
244 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, requested, CTLFLAG_RD,
245 &forward_wakeups_requested, 0,
246 "Requests for Forwarding of wakeup to idle CPUs");
247
248 static int forward_wakeups_delivered = 0;
249 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, delivered, CTLFLAG_RD,
250 &forward_wakeups_delivered, 0,
251 "Completed Forwarding of wakeup to idle CPUs");
252
253 static int forward_wakeup_use_mask = 1;
254 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, usemask, CTLFLAG_RW,
255 &forward_wakeup_use_mask, 0,
256 "Use the mask of idle cpus");
257
258 static int forward_wakeup_use_loop = 0;
259 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, useloop, CTLFLAG_RW,
260 &forward_wakeup_use_loop, 0,
261 "Use a loop to find idle cpus");
262
263 static int forward_wakeup_use_single = 0;
264 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, onecpu, CTLFLAG_RW,
265 &forward_wakeup_use_single, 0,
266 "Only signal one idle cpu");
267
268 static int forward_wakeup_use_htt = 0;
269 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, htt2, CTLFLAG_RW,
270 &forward_wakeup_use_htt, 0,
271 "account for htt");
272
273 #endif
274 static int sched_followon = 0;
275 SYSCTL_INT(_kern_sched, OID_AUTO, followon, CTLFLAG_RW,
276 &sched_followon, 0,
277 "allow threads to share a quantum");
278
279 static int sched_pfollowons = 0;
280 SYSCTL_INT(_kern_sched, OID_AUTO, pfollowons, CTLFLAG_RD,
281 &sched_pfollowons, 0,
282 "number of followons done to a different ksegrp");
283
284 static int sched_kgfollowons = 0;
285 SYSCTL_INT(_kern_sched, OID_AUTO, kgfollowons, CTLFLAG_RD,
286 &sched_kgfollowons, 0,
287 "number of followons done in a ksegrp");
288
289 static __inline void
290 sched_load_add(void)
291 {
292 sched_tdcnt++;
293 CTR1(KTR_SCHED, "global load: %d", sched_tdcnt);
294 }
295
296 static __inline void
297 sched_load_rem(void)
298 {
299 sched_tdcnt--;
300 CTR1(KTR_SCHED, "global load: %d", sched_tdcnt);
301 }
302 /*
303 * Arrange to reschedule if necessary, taking the priorities and
304 * schedulers into account.
305 */
306 static void
307 maybe_resched(struct thread *td)
308 {
309
310 mtx_assert(&sched_lock, MA_OWNED);
311 if (td->td_priority < curthread->td_priority)
312 curthread->td_flags |= TDF_NEEDRESCHED;
313 }
314
315 /*
316 * Constants for digital decay and forget:
317 * 90% of (kg_estcpu) usage in 5 * loadav time
318 * 95% of (ke_pctcpu) usage in 60 seconds (load insensitive)
319 * Note that, as ps(1) mentions, this can let percentages
320 * total over 100% (I've seen 137.9% for 3 processes).
321 *
322 * Note that schedclock() updates kg_estcpu and p_cpticks asynchronously.
323 *
324 * We wish to decay away 90% of kg_estcpu in (5 * loadavg) seconds.
325 * That is, the system wants to compute a value of decay such
326 * that the following for loop:
327 * for (i = 0; i < (5 * loadavg); i++)
328 * kg_estcpu *= decay;
329 * will compute
330 * kg_estcpu *= 0.1;
331 * for all values of loadavg:
332 *
333 * Mathematically this loop can be expressed by saying:
334 * decay ** (5 * loadavg) ~= .1
335 *
336 * The system computes decay as:
337 * decay = (2 * loadavg) / (2 * loadavg + 1)
338 *
339 * We wish to prove that the system's computation of decay
340 * will always fulfill the equation:
341 * decay ** (5 * loadavg) ~= .1
342 *
343 * If we compute b as:
344 * b = 2 * loadavg
345 * then
346 * decay = b / (b + 1)
347 *
348 * We now need to prove two things:
349 * 1) Given factor ** (5 * loadavg) ~= .1, prove factor == b/(b+1)
350 * 2) Given b/(b+1) ** power ~= .1, prove power == (5 * loadavg)
351 *
352 * Facts:
353 * For x close to zero, exp(x) =~ 1 + x, since
354 * exp(x) = 0! + x**1/1! + x**2/2! + ... .
355 * therefore exp(-1/b) =~ 1 - (1/b) = (b-1)/b.
356 * For x close to zero, ln(1+x) =~ x, since
357 * ln(1+x) = x - x**2/2 + x**3/3 - ... -1 < x < 1
358 * therefore ln(b/(b+1)) = ln(1 - 1/(b+1)) =~ -1/(b+1).
359 * ln(.1) =~ -2.30
360 *
361 * Proof of (1):
362 * Solve (factor)**(power) =~ .1 given power (5*loadav):
363 * solving for factor,
364 * ln(factor) =~ (-2.30/5*loadav), or
365 * factor =~ exp(-1/((5/2.30)*loadav)) =~ exp(-1/(2*loadav)) =
366 * exp(-1/b) =~ (b-1)/b =~ b/(b+1). QED
367 *
368 * Proof of (2):
369 * Solve (factor)**(power) =~ .1 given factor == (b/(b+1)):
370 * solving for power,
371 * power*ln(b/(b+1)) =~ -2.30, or
372 * power =~ 2.3 * (b + 1) = 4.6*loadav + 2.3 =~ 5*loadav. QED
373 *
374 * Actual power values for the implemented algorithm are as follows:
375 * loadav: 1 2 3 4
376 * power: 5.68 10.32 14.94 19.55
377 */
378
379 /* calculations for digital decay to forget 90% of usage in 5*loadav sec */
380 #define loadfactor(loadav) (2 * (loadav))
381 #define decay_cpu(loadfac, cpu) (((loadfac) * (cpu)) / ((loadfac) + FSCALE))
382
383 /* decay 95% of `ke_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */
384 static fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */
385 SYSCTL_INT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, "");
386
387 /*
388 * If `ccpu' is not equal to `exp(-1/20)' and you still want to use the
389 * faster/more-accurate formula, you'll have to estimate CCPU_SHIFT below
390 * and possibly adjust FSHIFT in "param.h" so that (FSHIFT >= CCPU_SHIFT).
391 *
392 * To estimate CCPU_SHIFT for exp(-1/20), the following formula was used:
393 * 1 - exp(-1/20) ~= 0.0487 ~= 0.0488 == 1 (fixed pt, *11* bits).
394 *
395 * If you don't want to bother with the faster/more-accurate formula, you
396 * can set CCPU_SHIFT to (FSHIFT + 1) which will use a slower/less-accurate
397 * (more general) method of calculating the %age of CPU used by a process.
398 */
399 #define CCPU_SHIFT 11
400
401 /*
402 * Recompute process priorities, every hz ticks.
403 * MP-safe, called without the Giant mutex.
404 */
405 /* ARGSUSED */
406 static void
407 schedcpu(void)
408 {
409 register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]);
410 struct thread *td;
411 struct proc *p;
412 struct kse *ke;
413 struct ksegrp *kg;
414 int awake, realstathz;
415
416 realstathz = stathz ? stathz : hz;
417 sx_slock(&allproc_lock);
418 FOREACH_PROC_IN_SYSTEM(p) {
419 /*
420 * Prevent state changes and protect run queue.
421 */
422 mtx_lock_spin(&sched_lock);
423 /*
424 * Increment time in/out of memory. We ignore overflow; with
425 * 16-bit int's (remember them?) overflow takes 45 days.
426 */
427 p->p_swtime++;
428 FOREACH_KSEGRP_IN_PROC(p, kg) {
429 awake = 0;
430 FOREACH_THREAD_IN_GROUP(kg, td) {
431 ke = td->td_kse;
432 /*
433 * Increment sleep time (if sleeping). We
434 * ignore overflow, as above.
435 */
436 /*
437 * The kse slptimes are not touched in wakeup
438 * because the thread may not HAVE a KSE.
439 */
440 if (ke->ke_state == KES_ONRUNQ) {
441 awake = 1;
442 ke->ke_flags &= ~KEF_DIDRUN;
443 } else if ((ke->ke_state == KES_THREAD) &&
444 (TD_IS_RUNNING(td))) {
445 awake = 1;
446 /* Do not clear KEF_DIDRUN */
447 } else if (ke->ke_flags & KEF_DIDRUN) {
448 awake = 1;
449 ke->ke_flags &= ~KEF_DIDRUN;
450 }
451
452 /*
453 * ke_pctcpu is only for ps and ttyinfo().
454 * Do it per kse, and add them up at the end?
455 * XXXKSE
456 */
457 ke->ke_pctcpu = (ke->ke_pctcpu * ccpu) >>
458 FSHIFT;
459 /*
460 * If the kse has been idle the entire second,
461 * stop recalculating its priority until
462 * it wakes up.
463 */
464 if (ke->ke_cpticks == 0)
465 continue;
466 #if (FSHIFT >= CCPU_SHIFT)
467 ke->ke_pctcpu += (realstathz == 100)
468 ? ((fixpt_t) ke->ke_cpticks) <<
469 (FSHIFT - CCPU_SHIFT) :
470 100 * (((fixpt_t) ke->ke_cpticks)
471 << (FSHIFT - CCPU_SHIFT)) / realstathz;
472 #else
473 ke->ke_pctcpu += ((FSCALE - ccpu) *
474 (ke->ke_cpticks *
475 FSCALE / realstathz)) >> FSHIFT;
476 #endif
477 ke->ke_cpticks = 0;
478 } /* end of kse loop */
479 /*
480 * If there are ANY running threads in this KSEGRP,
481 * then don't count it as sleeping.
482 */
483 if (awake) {
484 if (kg->kg_slptime > 1) {
485 /*
486 * In an ideal world, this should not
487 * happen, because whoever woke us
488 * up from the long sleep should have
489 * unwound the slptime and reset our
490 * priority before we run at the stale
491 * priority. Should KASSERT at some
492 * point when all the cases are fixed.
493 */
494 updatepri(kg);
495 }
496 kg->kg_slptime = 0;
497 } else
498 kg->kg_slptime++;
499 if (kg->kg_slptime > 1)
500 continue;
501 kg->kg_estcpu = decay_cpu(loadfac, kg->kg_estcpu);
502 resetpriority(kg);
503 FOREACH_THREAD_IN_GROUP(kg, td) {
504 resetpriority_thread(td, kg);
505 }
506 } /* end of ksegrp loop */
507 mtx_unlock_spin(&sched_lock);
508 } /* end of process loop */
509 sx_sunlock(&allproc_lock);
510 }
511
512 /*
513 * Main loop for a kthread that executes schedcpu once a second.
514 */
515 static void
516 schedcpu_thread(void)
517 {
518 int nowake;
519
520 for (;;) {
521 schedcpu();
522 tsleep(&nowake, 0, "-", hz);
523 }
524 }
525
526 /*
527 * Recalculate the priority of a process after it has slept for a while.
528 * For all load averages >= 1 and max kg_estcpu of 255, sleeping for at
529 * least six times the loadfactor will decay kg_estcpu to zero.
530 */
531 static void
532 updatepri(struct ksegrp *kg)
533 {
534 register fixpt_t loadfac;
535 register unsigned int newcpu;
536
537 loadfac = loadfactor(averunnable.ldavg[0]);
538 if (kg->kg_slptime > 5 * loadfac)
539 kg->kg_estcpu = 0;
540 else {
541 newcpu = kg->kg_estcpu;
542 kg->kg_slptime--; /* was incremented in schedcpu() */
543 while (newcpu && --kg->kg_slptime)
544 newcpu = decay_cpu(loadfac, newcpu);
545 kg->kg_estcpu = newcpu;
546 }
547 }
548
549 /*
550 * Compute the priority of a process when running in user mode.
551 * Arrange to reschedule if the resulting priority is better
552 * than that of the current process.
553 */
554 static void
555 resetpriority(struct ksegrp *kg)
556 {
557 register unsigned int newpriority;
558
559 if (kg->kg_pri_class == PRI_TIMESHARE) {
560 newpriority = PUSER + kg->kg_estcpu / INVERSE_ESTCPU_WEIGHT +
561 NICE_WEIGHT * (kg->kg_proc->p_nice - PRIO_MIN);
562 newpriority = min(max(newpriority, PRI_MIN_TIMESHARE),
563 PRI_MAX_TIMESHARE);
564 kg->kg_user_pri = newpriority;
565 }
566 }
567
568 /*
569 * Update the thread's priority when the associated ksegroup's user
570 * priority changes.
571 */
572 static void
573 resetpriority_thread(struct thread *td, struct ksegrp *kg)
574 {
575
576 /* Only change threads with a time sharing user priority. */
577 if (td->td_priority < PRI_MIN_TIMESHARE ||
578 td->td_priority > PRI_MAX_TIMESHARE)
579 return;
580
581 /* XXX the whole needresched thing is broken, but not silly. */
582 maybe_resched(td);
583
584 sched_prio(td, kg->kg_user_pri);
585 }
586
587 /* ARGSUSED */
588 static void
589 sched_setup(void *dummy)
590 {
591 setup_runqs();
592
593 if (sched_quantum == 0)
594 sched_quantum = SCHED_QUANTUM;
595 hogticks = 2 * sched_quantum;
596
597 /* Account for thread0. */
598 sched_load_add();
599 }
600
601 /* External interfaces start here */
602 /*
603 * Very early in the boot some setup of scheduler-specific
604 * parts of proc0 and of some scheduler resources needs to be done.
605 * Called from:
606 * proc0_init()
607 */
608 void
609 schedinit(void)
610 {
611 /*
612 * Set up the scheduler specific parts of proc0.
613 */
614 proc0.p_sched = NULL; /* XXX */
615 ksegrp0.kg_sched = &kg_sched0;
616 thread0.td_sched = &kse0;
617 kse0.ke_thread = &thread0;
618 kse0.ke_state = KES_THREAD;
619 kg_sched0.skg_concurrency = 1;
620 kg_sched0.skg_avail_opennings = 0; /* we are already running */
621 }
622
623 int
624 sched_runnable(void)
625 {
626 #ifdef SMP
627 return runq_check(&runq) + runq_check(&runq_pcpu[PCPU_GET(cpuid)]);
628 #else
629 return runq_check(&runq);
630 #endif
631 }
632
633 int
634 sched_rr_interval(void)
635 {
636 if (sched_quantum == 0)
637 sched_quantum = SCHED_QUANTUM;
638 return (sched_quantum);
639 }
640
641 /*
642 * We adjust the priority of the current process. The priority of
643 * a process gets worse as it accumulates CPU time. The cpu usage
644 * estimator (kg_estcpu) is increased here. resetpriority() will
645 * compute a different priority each time kg_estcpu increases by
646 * INVERSE_ESTCPU_WEIGHT
647 * (until MAXPRI is reached). The cpu usage estimator ramps up
648 * quite quickly when the process is running (linearly), and decays
649 * away exponentially, at a rate which is proportionally slower when
650 * the system is busy. The basic principle is that the system will
651 * 90% forget that the process used a lot of CPU time in 5 * loadav
652 * seconds. This causes the system to favor processes which haven't
653 * run much recently, and to round-robin among other processes.
654 */
655 void
656 sched_clock(struct thread *td)
657 {
658 struct ksegrp *kg;
659 struct kse *ke;
660
661 mtx_assert(&sched_lock, MA_OWNED);
662 kg = td->td_ksegrp;
663 ke = td->td_kse;
664
665 ke->ke_cpticks++;
666 kg->kg_estcpu = ESTCPULIM(kg->kg_estcpu + 1);
667 if ((kg->kg_estcpu % INVERSE_ESTCPU_WEIGHT) == 0) {
668 resetpriority(kg);
669 resetpriority_thread(td, kg);
670 }
671
672 /*
673 * Force a context switch if the current thread has used up a full
674 * quantum (default quantum is 100ms).
675 */
676 if (td != PCPU_GET(idlethread) &&
677 ticks - PCPU_GET(switchticks) >= sched_quantum)
678 td->td_flags |= TDF_NEEDRESCHED;
679 }
680
681 /*
682 * charge childs scheduling cpu usage to parent.
683 *
684 * XXXKSE assume only one thread & kse & ksegrp keep estcpu in each ksegrp.
685 * Charge it to the ksegrp that did the wait since process estcpu is sum of
686 * all ksegrps, this is strictly as expected. Assume that the child process
687 * aggregated all the estcpu into the 'built-in' ksegrp.
688 */
689 void
690 sched_exit(struct proc *p, struct thread *td)
691 {
692 sched_exit_ksegrp(FIRST_KSEGRP_IN_PROC(p), td);
693 sched_exit_thread(FIRST_THREAD_IN_PROC(p), td);
694 }
695
696 void
697 sched_exit_ksegrp(struct ksegrp *kg, struct thread *childtd)
698 {
699
700 mtx_assert(&sched_lock, MA_OWNED);
701 kg->kg_estcpu = ESTCPULIM(kg->kg_estcpu + childtd->td_ksegrp->kg_estcpu);
702 }
703
704 void
705 sched_exit_thread(struct thread *td, struct thread *child)
706 {
707 CTR3(KTR_SCHED, "sched_exit_thread: %p(%s) prio %d",
708 child, child->td_proc->p_comm, child->td_priority);
709 if ((child->td_proc->p_flag & P_NOLOAD) == 0)
710 sched_load_rem();
711 }
712
713 void
714 sched_fork(struct thread *td, struct thread *childtd)
715 {
716 sched_fork_ksegrp(td, childtd->td_ksegrp);
717 sched_fork_thread(td, childtd);
718 }
719
720 void
721 sched_fork_ksegrp(struct thread *td, struct ksegrp *child)
722 {
723 mtx_assert(&sched_lock, MA_OWNED);
724 child->kg_estcpu = td->td_ksegrp->kg_estcpu;
725 }
726
727 void
728 sched_fork_thread(struct thread *td, struct thread *childtd)
729 {
730 sched_newthread(childtd);
731 }
732
733 void
734 sched_nice(struct proc *p, int nice)
735 {
736 struct ksegrp *kg;
737 struct thread *td;
738
739 PROC_LOCK_ASSERT(p, MA_OWNED);
740 mtx_assert(&sched_lock, MA_OWNED);
741 p->p_nice = nice;
742 FOREACH_KSEGRP_IN_PROC(p, kg) {
743 resetpriority(kg);
744 FOREACH_THREAD_IN_GROUP(kg, td) {
745 resetpriority_thread(td, kg);
746 }
747 }
748 }
749
750 void
751 sched_class(struct ksegrp *kg, int class)
752 {
753 mtx_assert(&sched_lock, MA_OWNED);
754 kg->kg_pri_class = class;
755 }
756
757 /*
758 * Adjust the priority of a thread.
759 * This may include moving the thread within the KSEGRP,
760 * changing the assignment of a kse to the thread,
761 * and moving a KSE in the system run queue.
762 */
763 static void
764 sched_priority(struct thread *td, u_char prio)
765 {
766 CTR6(KTR_SCHED, "sched_prio: %p(%s) prio %d newprio %d by %p(%s)",
767 td, td->td_proc->p_comm, td->td_priority, prio, curthread,
768 curthread->td_proc->p_comm);
769
770 mtx_assert(&sched_lock, MA_OWNED);
771 if (td->td_priority == prio)
772 return;
773 if (TD_ON_RUNQ(td)) {
774 adjustrunqueue(td, prio);
775 } else {
776 td->td_priority = prio;
777 }
778 }
779
780 /*
781 * Update a thread's priority when it is lent another thread's
782 * priority.
783 */
784 void
785 sched_lend_prio(struct thread *td, u_char prio)
786 {
787
788 td->td_flags |= TDF_BORROWING;
789 sched_priority(td, prio);
790 }
791
792 /*
793 * Restore a thread's priority when priority propagation is
794 * over. The prio argument is the minimum priority the thread
795 * needs to have to satisfy other possible priority lending
796 * requests. If the thread's regulary priority is less
797 * important than prio the thread will keep a priority boost
798 * of prio.
799 */
800 void
801 sched_unlend_prio(struct thread *td, u_char prio)
802 {
803 u_char base_pri;
804
805 if (td->td_base_pri >= PRI_MIN_TIMESHARE &&
806 td->td_base_pri <= PRI_MAX_TIMESHARE)
807 base_pri = td->td_ksegrp->kg_user_pri;
808 else
809 base_pri = td->td_base_pri;
810 if (prio >= base_pri) {
811 td->td_flags &= ~TDF_BORROWING;
812 sched_prio(td, base_pri);
813 } else
814 sched_lend_prio(td, prio);
815 }
816
817 void
818 sched_prio(struct thread *td, u_char prio)
819 {
820 u_char oldprio;
821
822 /* First, update the base priority. */
823 td->td_base_pri = prio;
824
825 /*
826 * If the thread is borrowing another thread's priority, don't ever
827 * lower the priority.
828 */
829 if (td->td_flags & TDF_BORROWING && td->td_priority < prio)
830 return;
831
832 /* Change the real priority. */
833 oldprio = td->td_priority;
834 sched_priority(td, prio);
835
836 /*
837 * If the thread is on a turnstile, then let the turnstile update
838 * its state.
839 */
840 if (TD_ON_LOCK(td) && oldprio != prio)
841 turnstile_adjust(td, oldprio);
842 }
843
844 void
845 sched_sleep(struct thread *td)
846 {
847
848 mtx_assert(&sched_lock, MA_OWNED);
849 td->td_ksegrp->kg_slptime = 0;
850 }
851
852 static void remrunqueue(struct thread *td);
853
854 void
855 sched_switch(struct thread *td, struct thread *newtd, int flags)
856 {
857 struct kse *ke;
858 struct ksegrp *kg;
859 struct proc *p;
860
861 ke = td->td_kse;
862 p = td->td_proc;
863
864 mtx_assert(&sched_lock, MA_OWNED);
865
866 if ((p->p_flag & P_NOLOAD) == 0)
867 sched_load_rem();
868 /*
869 * We are volunteering to switch out so we get to nominate
870 * a successor for the rest of our quantum
871 * First try another thread in our ksegrp, and then look for
872 * other ksegrps in our process.
873 */
874 if (sched_followon &&
875 (p->p_flag & P_HADTHREADS) &&
876 (flags & SW_VOL) &&
877 newtd == NULL) {
878 /* lets schedule another thread from this process */
879 kg = td->td_ksegrp;
880 if ((newtd = TAILQ_FIRST(&kg->kg_runq))) {
881 remrunqueue(newtd);
882 sched_kgfollowons++;
883 } else {
884 FOREACH_KSEGRP_IN_PROC(p, kg) {
885 if ((newtd = TAILQ_FIRST(&kg->kg_runq))) {
886 sched_pfollowons++;
887 remrunqueue(newtd);
888 break;
889 }
890 }
891 }
892 }
893
894 if (newtd)
895 newtd->td_flags |= (td->td_flags & TDF_NEEDRESCHED);
896
897 td->td_lastcpu = td->td_oncpu;
898 td->td_flags &= ~TDF_NEEDRESCHED;
899 td->td_owepreempt = 0;
900 td->td_oncpu = NOCPU;
901 /*
902 * At the last moment, if this thread is still marked RUNNING,
903 * then put it back on the run queue as it has not been suspended
904 * or stopped or any thing else similar. We never put the idle
905 * threads on the run queue, however.
906 */
907 if (td == PCPU_GET(idlethread))
908 TD_SET_CAN_RUN(td);
909 else {
910 SLOT_RELEASE(td->td_ksegrp);
911 if (TD_IS_RUNNING(td)) {
912 /* Put us back on the run queue (kse and all). */
913 setrunqueue(td, (flags & SW_PREEMPT) ?
914 SRQ_OURSELF|SRQ_YIELDING|SRQ_PREEMPTED :
915 SRQ_OURSELF|SRQ_YIELDING);
916 } else if (p->p_flag & P_HADTHREADS) {
917 /*
918 * We will not be on the run queue. So we must be
919 * sleeping or similar. As it's available,
920 * someone else can use the KSE if they need it.
921 * It's NOT available if we are about to need it
922 */
923 if (newtd == NULL || newtd->td_ksegrp != td->td_ksegrp)
924 slot_fill(td->td_ksegrp);
925 }
926 }
927 if (newtd) {
928 /*
929 * The thread we are about to run needs to be counted
930 * as if it had been added to the run queue and selected.
931 * It came from:
932 * * A preemption
933 * * An upcall
934 * * A followon
935 */
936 KASSERT((newtd->td_inhibitors == 0),
937 ("trying to run inhibitted thread"));
938 SLOT_USE(newtd->td_ksegrp);
939 newtd->td_kse->ke_flags |= KEF_DIDRUN;
940 TD_SET_RUNNING(newtd);
941 if ((newtd->td_proc->p_flag & P_NOLOAD) == 0)
942 sched_load_add();
943 } else {
944 newtd = choosethread();
945 }
946
947 if (td != newtd) {
948 #ifdef HWPMC_HOOKS
949 if (PMC_PROC_IS_USING_PMCS(td->td_proc))
950 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT);
951 #endif
952 cpu_switch(td, newtd);
953 #ifdef HWPMC_HOOKS
954 if (PMC_PROC_IS_USING_PMCS(td->td_proc))
955 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_IN);
956 #endif
957 }
958
959 sched_lock.mtx_lock = (uintptr_t)td;
960 td->td_oncpu = PCPU_GET(cpuid);
961 }
962
963 void
964 sched_wakeup(struct thread *td)
965 {
966 struct ksegrp *kg;
967
968 mtx_assert(&sched_lock, MA_OWNED);
969 kg = td->td_ksegrp;
970 if (kg->kg_slptime > 1) {
971 updatepri(kg);
972 resetpriority(kg);
973 }
974 kg->kg_slptime = 0;
975 setrunqueue(td, SRQ_BORING);
976 }
977
978 #ifdef SMP
979 /* enable HTT_2 if you have a 2-way HTT cpu.*/
980 static int
981 forward_wakeup(int cpunum)
982 {
983 cpumask_t map, me, dontuse;
984 cpumask_t map2;
985 struct pcpu *pc;
986 cpumask_t id, map3;
987
988 mtx_assert(&sched_lock, MA_OWNED);
989
990 CTR0(KTR_RUNQ, "forward_wakeup()");
991
992 if ((!forward_wakeup_enabled) ||
993 (forward_wakeup_use_mask == 0 && forward_wakeup_use_loop == 0))
994 return (0);
995 if (!smp_started || cold || panicstr)
996 return (0);
997
998 forward_wakeups_requested++;
999
1000 /*
1001 * check the idle mask we received against what we calculated before
1002 * in the old version.
1003 */
1004 me = PCPU_GET(cpumask);
1005 /*
1006 * don't bother if we should be doing it ourself..
1007 */
1008 if ((me & idle_cpus_mask) && (cpunum == NOCPU || me == (1 << cpunum)))
1009 return (0);
1010
1011 dontuse = me | stopped_cpus | hlt_cpus_mask;
1012 map3 = 0;
1013 if (forward_wakeup_use_loop) {
1014 SLIST_FOREACH(pc, &cpuhead, pc_allcpu) {
1015 id = pc->pc_cpumask;
1016 if ( (id & dontuse) == 0 &&
1017 pc->pc_curthread == pc->pc_idlethread) {
1018 map3 |= id;
1019 }
1020 }
1021 }
1022
1023 if (forward_wakeup_use_mask) {
1024 map = 0;
1025 map = idle_cpus_mask & ~dontuse;
1026
1027 /* If they are both on, compare and use loop if different */
1028 if (forward_wakeup_use_loop) {
1029 if (map != map3) {
1030 printf("map (%02X) != map3 (%02X)\n",
1031 map, map3);
1032 map = map3;
1033 }
1034 }
1035 } else {
1036 map = map3;
1037 }
1038 /* If we only allow a specific CPU, then mask off all the others */
1039 if (cpunum != NOCPU) {
1040 KASSERT((cpunum <= mp_maxcpus),("forward_wakeup: bad cpunum."));
1041 map &= (1 << cpunum);
1042 } else {
1043 /* Try choose an idle die. */
1044 if (forward_wakeup_use_htt) {
1045 map2 = (map & (map >> 1)) & 0x5555;
1046 if (map2) {
1047 map = map2;
1048 }
1049 }
1050
1051 /* set only one bit */
1052 if (forward_wakeup_use_single) {
1053 map = map & ((~map) + 1);
1054 }
1055 }
1056 if (map) {
1057 forward_wakeups_delivered++;
1058 ipi_selected(map, IPI_AST);
1059 return (1);
1060 }
1061 if (cpunum == NOCPU)
1062 printf("forward_wakeup: Idle processor not found\n");
1063 return (0);
1064 }
1065 #endif
1066
1067 #ifdef SMP
1068 static void kick_other_cpu(int pri,int cpuid);
1069
1070 static void
1071 kick_other_cpu(int pri,int cpuid)
1072 {
1073 struct pcpu * pcpu = pcpu_find(cpuid);
1074 int cpri = pcpu->pc_curthread->td_priority;
1075
1076 if (idle_cpus_mask & pcpu->pc_cpumask) {
1077 forward_wakeups_delivered++;
1078 ipi_selected(pcpu->pc_cpumask, IPI_AST);
1079 return;
1080 }
1081
1082 if (pri >= cpri)
1083 return;
1084
1085 #if defined(IPI_PREEMPTION) && defined(PREEMPTION)
1086 #if !defined(FULL_PREEMPTION)
1087 if (pri <= PRI_MAX_ITHD)
1088 #endif /* ! FULL_PREEMPTION */
1089 {
1090 ipi_selected(pcpu->pc_cpumask, IPI_PREEMPT);
1091 return;
1092 }
1093 #endif /* defined(IPI_PREEMPTION) && defined(PREEMPTION) */
1094
1095 pcpu->pc_curthread->td_flags |= TDF_NEEDRESCHED;
1096 ipi_selected( pcpu->pc_cpumask , IPI_AST);
1097 return;
1098 }
1099 #endif /* SMP */
1100
1101 void
1102 sched_add(struct thread *td, int flags)
1103 #ifdef SMP
1104 {
1105 struct kse *ke;
1106 int forwarded = 0;
1107 int cpu;
1108 int single_cpu = 0;
1109
1110 ke = td->td_kse;
1111 mtx_assert(&sched_lock, MA_OWNED);
1112 KASSERT(ke->ke_state != KES_ONRUNQ,
1113 ("sched_add: kse %p (%s) already in run queue", ke,
1114 ke->ke_proc->p_comm));
1115 KASSERT(ke->ke_proc->p_sflag & PS_INMEM,
1116 ("sched_add: process swapped out"));
1117 CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)",
1118 td, td->td_proc->p_comm, td->td_priority, curthread,
1119 curthread->td_proc->p_comm);
1120
1121
1122 if (td->td_pinned != 0) {
1123 cpu = td->td_lastcpu;
1124 ke->ke_runq = &runq_pcpu[cpu];
1125 single_cpu = 1;
1126 CTR3(KTR_RUNQ,
1127 "sched_add: Put kse:%p(td:%p) on cpu%d runq", ke, td, cpu);
1128 } else if ((ke)->ke_flags & KEF_BOUND) {
1129 /* Find CPU from bound runq */
1130 KASSERT(SKE_RUNQ_PCPU(ke),("sched_add: bound kse not on cpu runq"));
1131 cpu = ke->ke_runq - &runq_pcpu[0];
1132 single_cpu = 1;
1133 CTR3(KTR_RUNQ,
1134 "sched_add: Put kse:%p(td:%p) on cpu%d runq", ke, td, cpu);
1135 } else {
1136 CTR2(KTR_RUNQ,
1137 "sched_add: adding kse:%p (td:%p) to gbl runq", ke, td);
1138 cpu = NOCPU;
1139 ke->ke_runq = &runq;
1140 }
1141
1142 if (single_cpu && (cpu != PCPU_GET(cpuid))) {
1143 kick_other_cpu(td->td_priority,cpu);
1144 } else {
1145
1146 if (!single_cpu) {
1147 cpumask_t me = PCPU_GET(cpumask);
1148 int idle = idle_cpus_mask & me;
1149
1150 if (!idle && ((flags & SRQ_INTR) == 0) &&
1151 (idle_cpus_mask & ~(hlt_cpus_mask | me)))
1152 forwarded = forward_wakeup(cpu);
1153 }
1154
1155 if (!forwarded) {
1156 if ((flags & SRQ_YIELDING) == 0 && maybe_preempt(td))
1157 return;
1158 else
1159 maybe_resched(td);
1160 }
1161 }
1162
1163 if ((td->td_proc->p_flag & P_NOLOAD) == 0)
1164 sched_load_add();
1165 SLOT_USE(td->td_ksegrp);
1166 runq_add(ke->ke_runq, ke, flags);
1167 ke->ke_state = KES_ONRUNQ;
1168 }
1169 #else /* SMP */
1170 {
1171 struct kse *ke;
1172 ke = td->td_kse;
1173 mtx_assert(&sched_lock, MA_OWNED);
1174 KASSERT(ke->ke_state != KES_ONRUNQ,
1175 ("sched_add: kse %p (%s) already in run queue", ke,
1176 ke->ke_proc->p_comm));
1177 KASSERT(ke->ke_proc->p_sflag & PS_INMEM,
1178 ("sched_add: process swapped out"));
1179 CTR5(KTR_SCHED, "sched_add: %p(%s) prio %d by %p(%s)",
1180 td, td->td_proc->p_comm, td->td_priority, curthread,
1181 curthread->td_proc->p_comm);
1182 CTR2(KTR_RUNQ, "sched_add: adding kse:%p (td:%p) to runq", ke, td);
1183 ke->ke_runq = &runq;
1184
1185 /*
1186 * If we are yielding (on the way out anyhow)
1187 * or the thread being saved is US,
1188 * then don't try be smart about preemption
1189 * or kicking off another CPU
1190 * as it won't help and may hinder.
1191 * In the YIEDLING case, we are about to run whoever is
1192 * being put in the queue anyhow, and in the
1193 * OURSELF case, we are puting ourself on the run queue
1194 * which also only happens when we are about to yield.
1195 */
1196 if((flags & SRQ_YIELDING) == 0) {
1197 if (maybe_preempt(td))
1198 return;
1199 }
1200 if ((td->td_proc->p_flag & P_NOLOAD) == 0)
1201 sched_load_add();
1202 SLOT_USE(td->td_ksegrp);
1203 runq_add(ke->ke_runq, ke, flags);
1204 ke->ke_state = KES_ONRUNQ;
1205 maybe_resched(td);
1206 }
1207 #endif /* SMP */
1208
1209 void
1210 sched_rem(struct thread *td)
1211 {
1212 struct kse *ke;
1213
1214 ke = td->td_kse;
1215 KASSERT(ke->ke_proc->p_sflag & PS_INMEM,
1216 ("sched_rem: process swapped out"));
1217 KASSERT((ke->ke_state == KES_ONRUNQ),
1218 ("sched_rem: KSE not on run queue"));
1219 mtx_assert(&sched_lock, MA_OWNED);
1220 CTR5(KTR_SCHED, "sched_rem: %p(%s) prio %d by %p(%s)",
1221 td, td->td_proc->p_comm, td->td_priority, curthread,
1222 curthread->td_proc->p_comm);
1223
1224 if ((td->td_proc->p_flag & P_NOLOAD) == 0)
1225 sched_load_rem();
1226 SLOT_RELEASE(td->td_ksegrp);
1227 runq_remove(ke->ke_runq, ke);
1228
1229 ke->ke_state = KES_THREAD;
1230 }
1231
1232 /*
1233 * Select threads to run.
1234 * Notice that the running threads still consume a slot.
1235 */
1236 struct kse *
1237 sched_choose(void)
1238 {
1239 struct kse *ke;
1240 struct runq *rq;
1241
1242 #ifdef SMP
1243 struct kse *kecpu;
1244
1245 rq = &runq;
1246 ke = runq_choose(&runq);
1247 kecpu = runq_choose(&runq_pcpu[PCPU_GET(cpuid)]);
1248
1249 if (ke == NULL ||
1250 (kecpu != NULL &&
1251 kecpu->ke_thread->td_priority < ke->ke_thread->td_priority)) {
1252 CTR2(KTR_RUNQ, "choosing kse %p from pcpu runq %d", kecpu,
1253 PCPU_GET(cpuid));
1254 ke = kecpu;
1255 rq = &runq_pcpu[PCPU_GET(cpuid)];
1256 } else {
1257 CTR1(KTR_RUNQ, "choosing kse %p from main runq", ke);
1258 }
1259
1260 #else
1261 rq = &runq;
1262 ke = runq_choose(&runq);
1263 #endif
1264
1265 if (ke != NULL) {
1266 runq_remove(rq, ke);
1267 ke->ke_state = KES_THREAD;
1268
1269 KASSERT(ke->ke_proc->p_sflag & PS_INMEM,
1270 ("sched_choose: process swapped out"));
1271 }
1272 return (ke);
1273 }
1274
1275 void
1276 sched_userret(struct thread *td)
1277 {
1278 struct ksegrp *kg;
1279 /*
1280 * XXX we cheat slightly on the locking here to avoid locking in
1281 * the usual case. Setting td_priority here is essentially an
1282 * incomplete workaround for not setting it properly elsewhere.
1283 * Now that some interrupt handlers are threads, not setting it
1284 * properly elsewhere can clobber it in the window between setting
1285 * it here and returning to user mode, so don't waste time setting
1286 * it perfectly here.
1287 */
1288 KASSERT((td->td_flags & TDF_BORROWING) == 0,
1289 ("thread with borrowed priority returning to userland"));
1290 kg = td->td_ksegrp;
1291 if (td->td_priority != kg->kg_user_pri) {
1292 mtx_lock_spin(&sched_lock);
1293 td->td_priority = kg->kg_user_pri;
1294 td->td_base_pri = kg->kg_user_pri;
1295 mtx_unlock_spin(&sched_lock);
1296 }
1297 }
1298
1299 void
1300 sched_bind(struct thread *td, int cpu)
1301 {
1302 struct kse *ke;
1303
1304 mtx_assert(&sched_lock, MA_OWNED);
1305 KASSERT(TD_IS_RUNNING(td),
1306 ("sched_bind: cannot bind non-running thread"));
1307
1308 ke = td->td_kse;
1309
1310 ke->ke_flags |= KEF_BOUND;
1311 #ifdef SMP
1312 ke->ke_runq = &runq_pcpu[cpu];
1313 if (PCPU_GET(cpuid) == cpu)
1314 return;
1315
1316 ke->ke_state = KES_THREAD;
1317
1318 mi_switch(SW_VOL, NULL);
1319 #endif
1320 }
1321
1322 void
1323 sched_unbind(struct thread* td)
1324 {
1325 mtx_assert(&sched_lock, MA_OWNED);
1326 td->td_kse->ke_flags &= ~KEF_BOUND;
1327 }
1328
1329 int
1330 sched_is_bound(struct thread *td)
1331 {
1332 mtx_assert(&sched_lock, MA_OWNED);
1333 return (td->td_kse->ke_flags & KEF_BOUND);
1334 }
1335
1336 int
1337 sched_load(void)
1338 {
1339 return (sched_tdcnt);
1340 }
1341
1342 int
1343 sched_sizeof_ksegrp(void)
1344 {
1345 return (sizeof(struct ksegrp) + sizeof(struct kg_sched));
1346 }
1347 int
1348 sched_sizeof_proc(void)
1349 {
1350 return (sizeof(struct proc));
1351 }
1352 int
1353 sched_sizeof_thread(void)
1354 {
1355 return (sizeof(struct thread) + sizeof(struct kse));
1356 }
1357
1358 fixpt_t
1359 sched_pctcpu(struct thread *td)
1360 {
1361 struct kse *ke;
1362
1363 ke = td->td_kse;
1364 return (ke->ke_pctcpu);
1365
1366 return (0);
1367 }
1368 #define KERN_SWITCH_INCLUDE 1
1369 #include "kern/kern_switch.c"
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