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.
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35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
38 #include "opt_hwpmc_hooks.h"
39 #include "opt_sched.h"
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/cpuset.h>
44 #include <sys/kernel.h>
47 #include <sys/kthread.h>
48 #include <sys/mutex.h>
50 #include <sys/resourcevar.h>
51 #include <sys/sched.h>
54 #include <sys/sysctl.h>
56 #include <sys/turnstile.h>
58 #include <machine/pcb.h>
59 #include <machine/smp.h>
62 #include <sys/pmckern.h>
66 #include <sys/dtrace_bsd.h>
67 int dtrace_vtime_active;
68 dtrace_vtime_switch_func_t dtrace_vtime_switch_func;
72 * INVERSE_ESTCPU_WEIGHT is only suitable for statclock() frequencies in
73 * the range 100-256 Hz (approximately).
75 #define ESTCPULIM(e) \
76 min((e), INVERSE_ESTCPU_WEIGHT * (NICE_WEIGHT * (PRIO_MAX - PRIO_MIN) - \
77 RQ_PPQ) + INVERSE_ESTCPU_WEIGHT - 1)
79 #define INVERSE_ESTCPU_WEIGHT (8 * smp_cpus)
81 #define INVERSE_ESTCPU_WEIGHT 8 /* 1 / (priorities per estcpu level). */
83 #define NICE_WEIGHT 1 /* Priorities per nice level. */
85 #define TS_NAME_LEN (MAXCOMLEN + sizeof(" td ") + sizeof(__XSTRING(UINT_MAX)))
88 * The schedulable entity that runs a context.
89 * This is an extension to the thread structure and is tailored to
90 * the requirements of this scheduler.
91 * All fields are protected by the scheduler lock.
94 fixpt_t ts_pctcpu; /* %cpu during p_swtime. */
95 u_int ts_estcpu; /* Estimated cpu utilization. */
96 int ts_cpticks; /* Ticks of cpu time. */
97 int ts_slptime; /* Seconds !RUNNING. */
98 int ts_slice; /* Remaining part of time slice. */
100 struct runq *ts_runq; /* runq the thread is currently on */
102 char ts_name[TS_NAME_LEN];
106 /* flags kept in td_flags */
107 #define TDF_DIDRUN TDF_SCHED0 /* thread actually ran. */
108 #define TDF_BOUND TDF_SCHED1 /* Bound to one CPU. */
109 #define TDF_SLICEEND TDF_SCHED2 /* Thread time slice is over. */
111 /* flags kept in ts_flags */
112 #define TSF_AFFINITY 0x0001 /* Has a non-"full" CPU set. */
114 #define SKE_RUNQ_PCPU(ts) \
115 ((ts)->ts_runq != 0 && (ts)->ts_runq != &runq)
117 #define THREAD_CAN_SCHED(td, cpu) \
118 CPU_ISSET((cpu), &(td)->td_cpuset->cs_mask)
120 _Static_assert(sizeof(struct thread) + sizeof(struct td_sched) <=
121 sizeof(struct thread0_storage),
122 "increase struct thread0_storage.t0st_sched size");
124 static struct mtx sched_lock;
126 static int realstathz = 127; /* stathz is sometimes 0 and run off of hz. */
127 static int sched_tdcnt; /* Total runnable threads in the system. */
128 static int sched_slice = 12; /* Thread run time before rescheduling. */
130 static void setup_runqs(void);
131 static void schedcpu(void);
132 static void schedcpu_thread(void);
133 static void sched_priority(struct thread *td, u_char prio);
134 static void sched_setup(void *dummy);
135 static void maybe_resched(struct thread *td);
136 static void updatepri(struct thread *td);
137 static void resetpriority(struct thread *td);
138 static void resetpriority_thread(struct thread *td);
140 static int sched_pickcpu(struct thread *td);
141 static int forward_wakeup(int cpunum);
142 static void kick_other_cpu(int pri, int cpuid);
145 static struct kproc_desc sched_kp = {
150 SYSINIT(schedcpu, SI_SUB_LAST, SI_ORDER_FIRST, kproc_start,
152 SYSINIT(sched_setup, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, sched_setup, NULL);
154 static void sched_initticks(void *dummy);
155 SYSINIT(sched_initticks, SI_SUB_CLOCKS, SI_ORDER_THIRD, sched_initticks,
161 static struct runq runq;
167 static struct runq runq_pcpu[MAXCPU];
168 long runq_length[MAXCPU];
170 static cpuset_t idle_cpus_mask;
173 struct pcpuidlestat {
177 static DPCPU_DEFINE(struct pcpuidlestat, idlestat);
185 for (i = 0; i < MAXCPU; ++i)
186 runq_init(&runq_pcpu[i]);
193 sysctl_kern_quantum(SYSCTL_HANDLER_ARGS)
195 int error, new_val, period;
197 period = 1000000 / realstathz;
198 new_val = period * sched_slice;
199 error = sysctl_handle_int(oidp, &new_val, 0, req);
200 if (error != 0 || req->newptr == NULL)
204 sched_slice = imax(1, (new_val + period / 2) / period);
205 hogticks = imax(1, (2 * hz * sched_slice + realstathz / 2) /
210 SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RD, 0, "Scheduler");
212 SYSCTL_STRING(_kern_sched, OID_AUTO, name, CTLFLAG_RD, "4BSD", 0,
214 SYSCTL_PROC(_kern_sched, OID_AUTO, quantum, CTLTYPE_INT | CTLFLAG_RW,
215 NULL, 0, sysctl_kern_quantum, "I",
216 "Quantum for timeshare threads in microseconds");
217 SYSCTL_INT(_kern_sched, OID_AUTO, slice, CTLFLAG_RW, &sched_slice, 0,
218 "Quantum for timeshare threads in stathz ticks");
220 /* Enable forwarding of wakeups to all other cpus */
221 static SYSCTL_NODE(_kern_sched, OID_AUTO, ipiwakeup, CTLFLAG_RD, NULL,
224 static int runq_fuzz = 1;
225 SYSCTL_INT(_kern_sched, OID_AUTO, runq_fuzz, CTLFLAG_RW, &runq_fuzz, 0, "");
227 static int forward_wakeup_enabled = 1;
228 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, enabled, CTLFLAG_RW,
229 &forward_wakeup_enabled, 0,
230 "Forwarding of wakeup to idle CPUs");
232 static int forward_wakeups_requested = 0;
233 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, requested, CTLFLAG_RD,
234 &forward_wakeups_requested, 0,
235 "Requests for Forwarding of wakeup to idle CPUs");
237 static int forward_wakeups_delivered = 0;
238 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, delivered, CTLFLAG_RD,
239 &forward_wakeups_delivered, 0,
240 "Completed Forwarding of wakeup to idle CPUs");
242 static int forward_wakeup_use_mask = 1;
243 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, usemask, CTLFLAG_RW,
244 &forward_wakeup_use_mask, 0,
245 "Use the mask of idle cpus");
247 static int forward_wakeup_use_loop = 0;
248 SYSCTL_INT(_kern_sched_ipiwakeup, OID_AUTO, useloop, CTLFLAG_RW,
249 &forward_wakeup_use_loop, 0,
250 "Use a loop to find idle cpus");
254 static int sched_followon = 0;
255 SYSCTL_INT(_kern_sched, OID_AUTO, followon, CTLFLAG_RW,
257 "allow threads to share a quantum");
260 SDT_PROVIDER_DEFINE(sched);
262 SDT_PROBE_DEFINE3(sched, , , change__pri, "struct thread *",
263 "struct proc *", "uint8_t");
264 SDT_PROBE_DEFINE3(sched, , , dequeue, "struct thread *",
265 "struct proc *", "void *");
266 SDT_PROBE_DEFINE4(sched, , , enqueue, "struct thread *",
267 "struct proc *", "void *", "int");
268 SDT_PROBE_DEFINE4(sched, , , lend__pri, "struct thread *",
269 "struct proc *", "uint8_t", "struct thread *");
270 SDT_PROBE_DEFINE2(sched, , , load__change, "int", "int");
271 SDT_PROBE_DEFINE2(sched, , , off__cpu, "struct thread *",
273 SDT_PROBE_DEFINE(sched, , , on__cpu);
274 SDT_PROBE_DEFINE(sched, , , remain__cpu);
275 SDT_PROBE_DEFINE2(sched, , , surrender, "struct thread *",
283 KTR_COUNTER0(KTR_SCHED, "load", "global load", sched_tdcnt);
284 SDT_PROBE2(sched, , , load__change, NOCPU, sched_tdcnt);
292 KTR_COUNTER0(KTR_SCHED, "load", "global load", sched_tdcnt);
293 SDT_PROBE2(sched, , , load__change, NOCPU, sched_tdcnt);
296 * Arrange to reschedule if necessary, taking the priorities and
297 * schedulers into account.
300 maybe_resched(struct thread *td)
303 THREAD_LOCK_ASSERT(td, MA_OWNED);
304 if (td->td_priority < curthread->td_priority)
305 curthread->td_flags |= TDF_NEEDRESCHED;
309 * This function is called when a thread is about to be put on run queue
310 * because it has been made runnable or its priority has been adjusted. It
311 * determines if the new thread should be immediately preempted to. If so,
312 * it switches to it and eventually returns true. If not, it returns false
313 * so that the caller may place the thread on an appropriate run queue.
316 maybe_preempt(struct thread *td)
323 * The new thread should not preempt the current thread if any of the
324 * following conditions are true:
326 * - The kernel is in the throes of crashing (panicstr).
327 * - The current thread has a higher (numerically lower) or
328 * equivalent priority. Note that this prevents curthread from
329 * trying to preempt to itself.
330 * - It is too early in the boot for context switches (cold is set).
331 * - The current thread has an inhibitor set or is in the process of
332 * exiting. In this case, the current thread is about to switch
333 * out anyways, so there's no point in preempting. If we did,
334 * the current thread would not be properly resumed as well, so
335 * just avoid that whole landmine.
336 * - If the new thread's priority is not a realtime priority and
337 * the current thread's priority is not an idle priority and
338 * FULL_PREEMPTION is disabled.
340 * If all of these conditions are false, but the current thread is in
341 * a nested critical section, then we have to defer the preemption
342 * until we exit the critical section. Otherwise, switch immediately
346 THREAD_LOCK_ASSERT(td, MA_OWNED);
347 KASSERT((td->td_inhibitors == 0),
348 ("maybe_preempt: trying to run inhibited thread"));
349 pri = td->td_priority;
350 cpri = ctd->td_priority;
351 if (panicstr != NULL || pri >= cpri || cold /* || dumping */ ||
352 TD_IS_INHIBITED(ctd))
354 #ifndef FULL_PREEMPTION
355 if (pri > PRI_MAX_ITHD && cpri < PRI_MIN_IDLE)
359 if (ctd->td_critnest > 1) {
360 CTR1(KTR_PROC, "maybe_preempt: in critical section %d",
362 ctd->td_owepreempt = 1;
366 * Thread is runnable but not yet put on system run queue.
368 MPASS(ctd->td_lock == td->td_lock);
369 MPASS(TD_ON_RUNQ(td));
371 CTR3(KTR_PROC, "preempting to thread %p (pid %d, %s)\n", td,
372 td->td_proc->p_pid, td->td_name);
373 mi_switch(SW_INVOL | SW_PREEMPT | SWT_PREEMPT, td);
375 * td's lock pointer may have changed. We have to return with it
389 * Constants for digital decay and forget:
390 * 90% of (ts_estcpu) usage in 5 * loadav time
391 * 95% of (ts_pctcpu) usage in 60 seconds (load insensitive)
392 * Note that, as ps(1) mentions, this can let percentages
393 * total over 100% (I've seen 137.9% for 3 processes).
395 * Note that schedclock() updates ts_estcpu and p_cpticks asynchronously.
397 * We wish to decay away 90% of ts_estcpu in (5 * loadavg) seconds.
398 * That is, the system wants to compute a value of decay such
399 * that the following for loop:
400 * for (i = 0; i < (5 * loadavg); i++)
401 * ts_estcpu *= decay;
404 * for all values of loadavg:
406 * Mathematically this loop can be expressed by saying:
407 * decay ** (5 * loadavg) ~= .1
409 * The system computes decay as:
410 * decay = (2 * loadavg) / (2 * loadavg + 1)
412 * We wish to prove that the system's computation of decay
413 * will always fulfill the equation:
414 * decay ** (5 * loadavg) ~= .1
416 * If we compute b as:
419 * decay = b / (b + 1)
421 * We now need to prove two things:
422 * 1) Given factor ** (5 * loadavg) ~= .1, prove factor == b/(b+1)
423 * 2) Given b/(b+1) ** power ~= .1, prove power == (5 * loadavg)
426 * For x close to zero, exp(x) =~ 1 + x, since
427 * exp(x) = 0! + x**1/1! + x**2/2! + ... .
428 * therefore exp(-1/b) =~ 1 - (1/b) = (b-1)/b.
429 * For x close to zero, ln(1+x) =~ x, since
430 * ln(1+x) = x - x**2/2 + x**3/3 - ... -1 < x < 1
431 * therefore ln(b/(b+1)) = ln(1 - 1/(b+1)) =~ -1/(b+1).
435 * Solve (factor)**(power) =~ .1 given power (5*loadav):
436 * solving for factor,
437 * ln(factor) =~ (-2.30/5*loadav), or
438 * factor =~ exp(-1/((5/2.30)*loadav)) =~ exp(-1/(2*loadav)) =
439 * exp(-1/b) =~ (b-1)/b =~ b/(b+1). QED
442 * Solve (factor)**(power) =~ .1 given factor == (b/(b+1)):
444 * power*ln(b/(b+1)) =~ -2.30, or
445 * power =~ 2.3 * (b + 1) = 4.6*loadav + 2.3 =~ 5*loadav. QED
447 * Actual power values for the implemented algorithm are as follows:
449 * power: 5.68 10.32 14.94 19.55
452 /* calculations for digital decay to forget 90% of usage in 5*loadav sec */
453 #define loadfactor(loadav) (2 * (loadav))
454 #define decay_cpu(loadfac, cpu) (((loadfac) * (cpu)) / ((loadfac) + FSCALE))
456 /* decay 95% of `ts_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */
457 static fixpt_t ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */
458 SYSCTL_UINT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, "");
461 * If `ccpu' is not equal to `exp(-1/20)' and you still want to use the
462 * faster/more-accurate formula, you'll have to estimate CCPU_SHIFT below
463 * and possibly adjust FSHIFT in "param.h" so that (FSHIFT >= CCPU_SHIFT).
465 * To estimate CCPU_SHIFT for exp(-1/20), the following formula was used:
466 * 1 - exp(-1/20) ~= 0.0487 ~= 0.0488 == 1 (fixed pt, *11* bits).
468 * If you don't want to bother with the faster/more-accurate formula, you
469 * can set CCPU_SHIFT to (FSHIFT + 1) which will use a slower/less-accurate
470 * (more general) method of calculating the %age of CPU used by a process.
472 #define CCPU_SHIFT 11
475 * Recompute process priorities, every hz ticks.
476 * MP-safe, called without the Giant mutex.
482 register fixpt_t loadfac = loadfactor(averunnable.ldavg[0]);
488 sx_slock(&allproc_lock);
489 FOREACH_PROC_IN_SYSTEM(p) {
491 if (p->p_state == PRS_NEW) {
495 FOREACH_THREAD_IN_PROC(p, td) {
497 ts = td_get_sched(td);
500 * Increment sleep time (if sleeping). We
501 * ignore overflow, as above.
504 * The td_sched slptimes are not touched in wakeup
505 * because the thread may not HAVE everything in
506 * memory? XXX I think this is out of date.
508 if (TD_ON_RUNQ(td)) {
510 td->td_flags &= ~TDF_DIDRUN;
511 } else if (TD_IS_RUNNING(td)) {
513 /* Do not clear TDF_DIDRUN */
514 } else if (td->td_flags & TDF_DIDRUN) {
516 td->td_flags &= ~TDF_DIDRUN;
520 * ts_pctcpu is only for ps and ttyinfo().
522 ts->ts_pctcpu = (ts->ts_pctcpu * ccpu) >> FSHIFT;
524 * If the td_sched has been idle the entire second,
525 * stop recalculating its priority until
528 if (ts->ts_cpticks != 0) {
529 #if (FSHIFT >= CCPU_SHIFT)
530 ts->ts_pctcpu += (realstathz == 100)
531 ? ((fixpt_t) ts->ts_cpticks) <<
532 (FSHIFT - CCPU_SHIFT) :
533 100 * (((fixpt_t) ts->ts_cpticks)
534 << (FSHIFT - CCPU_SHIFT)) / realstathz;
536 ts->ts_pctcpu += ((FSCALE - ccpu) *
538 FSCALE / realstathz)) >> FSHIFT;
543 * If there are ANY running threads in this process,
544 * then don't count it as sleeping.
545 * XXX: this is broken.
548 if (ts->ts_slptime > 1) {
550 * In an ideal world, this should not
551 * happen, because whoever woke us
552 * up from the long sleep should have
553 * unwound the slptime and reset our
554 * priority before we run at the stale
555 * priority. Should KASSERT at some
556 * point when all the cases are fixed.
563 if (ts->ts_slptime > 1) {
567 ts->ts_estcpu = decay_cpu(loadfac, ts->ts_estcpu);
569 resetpriority_thread(td);
574 sx_sunlock(&allproc_lock);
578 * Main loop for a kthread that executes schedcpu once a second.
581 schedcpu_thread(void)
591 * Recalculate the priority of a process after it has slept for a while.
592 * For all load averages >= 1 and max ts_estcpu of 255, sleeping for at
593 * least six times the loadfactor will decay ts_estcpu to zero.
596 updatepri(struct thread *td)
602 ts = td_get_sched(td);
603 loadfac = loadfactor(averunnable.ldavg[0]);
604 if (ts->ts_slptime > 5 * loadfac)
607 newcpu = ts->ts_estcpu;
608 ts->ts_slptime--; /* was incremented in schedcpu() */
609 while (newcpu && --ts->ts_slptime)
610 newcpu = decay_cpu(loadfac, newcpu);
611 ts->ts_estcpu = newcpu;
616 * Compute the priority of a process when running in user mode.
617 * Arrange to reschedule if the resulting priority is better
618 * than that of the current process.
621 resetpriority(struct thread *td)
625 if (td->td_pri_class != PRI_TIMESHARE)
627 newpriority = PUSER +
628 td_get_sched(td)->ts_estcpu / INVERSE_ESTCPU_WEIGHT +
629 NICE_WEIGHT * (td->td_proc->p_nice - PRIO_MIN);
630 newpriority = min(max(newpriority, PRI_MIN_TIMESHARE),
632 sched_user_prio(td, newpriority);
636 * Update the thread's priority when the associated process's user
640 resetpriority_thread(struct thread *td)
643 /* Only change threads with a time sharing user priority. */
644 if (td->td_priority < PRI_MIN_TIMESHARE ||
645 td->td_priority > PRI_MAX_TIMESHARE)
648 /* XXX the whole needresched thing is broken, but not silly. */
651 sched_prio(td, td->td_user_pri);
656 sched_setup(void *dummy)
661 /* Account for thread0. */
666 * This routine determines time constants after stathz and hz are setup.
669 sched_initticks(void *dummy)
672 realstathz = stathz ? stathz : hz;
673 sched_slice = realstathz / 10; /* ~100ms */
674 hogticks = imax(1, (2 * hz * sched_slice + realstathz / 2) /
678 /* External interfaces start here */
681 * Very early in the boot some setup of scheduler-specific
682 * parts of proc0 and of some scheduler resources needs to be done.
691 * Set up the scheduler specific parts of thread0.
693 thread0.td_lock = &sched_lock;
694 td_get_sched(&thread0)->ts_slice = sched_slice;
695 mtx_init(&sched_lock, "sched lock", NULL, MTX_SPIN | MTX_RECURSE);
702 return runq_check(&runq) + runq_check(&runq_pcpu[PCPU_GET(cpuid)]);
704 return runq_check(&runq);
709 sched_rr_interval(void)
712 /* Convert sched_slice from stathz to hz. */
713 return (imax(1, (sched_slice * hz + realstathz / 2) / realstathz));
717 * We adjust the priority of the current process. The priority of a
718 * process gets worse as it accumulates CPU time. The cpu usage
719 * estimator (ts_estcpu) is increased here. resetpriority() will
720 * compute a different priority each time ts_estcpu increases by
721 * INVERSE_ESTCPU_WEIGHT (until PRI_MAX_TIMESHARE is reached). The
722 * cpu usage estimator ramps up quite quickly when the process is
723 * running (linearly), and decays away exponentially, at a rate which
724 * is proportionally slower when the system is busy. The basic
725 * principle is that the system will 90% forget that the process used
726 * a lot of CPU time in 5 * loadav seconds. This causes the system to
727 * favor processes which haven't run much recently, and to round-robin
728 * among other processes.
731 sched_clock(struct thread *td)
733 struct pcpuidlestat *stat;
736 THREAD_LOCK_ASSERT(td, MA_OWNED);
737 ts = td_get_sched(td);
740 ts->ts_estcpu = ESTCPULIM(ts->ts_estcpu + 1);
741 if ((ts->ts_estcpu % INVERSE_ESTCPU_WEIGHT) == 0) {
743 resetpriority_thread(td);
747 * Force a context switch if the current thread has used up a full
748 * time slice (default is 100ms).
750 if (!TD_IS_IDLETHREAD(td) && --ts->ts_slice <= 0) {
751 ts->ts_slice = sched_slice;
752 td->td_flags |= TDF_NEEDRESCHED | TDF_SLICEEND;
755 stat = DPCPU_PTR(idlestat);
756 stat->oldidlecalls = stat->idlecalls;
761 * Charge child's scheduling CPU usage to parent.
764 sched_exit(struct proc *p, struct thread *td)
767 KTR_STATE1(KTR_SCHED, "thread", sched_tdname(td), "proc exit",
768 "prio:%d", td->td_priority);
770 PROC_LOCK_ASSERT(p, MA_OWNED);
771 sched_exit_thread(FIRST_THREAD_IN_PROC(p), td);
775 sched_exit_thread(struct thread *td, struct thread *child)
778 KTR_STATE1(KTR_SCHED, "thread", sched_tdname(child), "exit",
779 "prio:%d", child->td_priority);
781 td_get_sched(td)->ts_estcpu = ESTCPULIM(td_get_sched(td)->ts_estcpu +
782 td_get_sched(child)->ts_estcpu);
785 if ((child->td_flags & TDF_NOLOAD) == 0)
787 thread_unlock(child);
791 sched_fork(struct thread *td, struct thread *childtd)
793 sched_fork_thread(td, childtd);
797 sched_fork_thread(struct thread *td, struct thread *childtd)
799 struct td_sched *ts, *tsc;
801 childtd->td_oncpu = NOCPU;
802 childtd->td_lastcpu = NOCPU;
803 childtd->td_lock = &sched_lock;
804 childtd->td_cpuset = cpuset_ref(td->td_cpuset);
805 childtd->td_priority = childtd->td_base_pri;
806 ts = td_get_sched(childtd);
807 bzero(ts, sizeof(*ts));
808 tsc = td_get_sched(td);
809 ts->ts_estcpu = tsc->ts_estcpu;
810 ts->ts_flags |= (tsc->ts_flags & TSF_AFFINITY);
815 sched_nice(struct proc *p, int nice)
819 PROC_LOCK_ASSERT(p, MA_OWNED);
821 FOREACH_THREAD_IN_PROC(p, td) {
824 resetpriority_thread(td);
830 sched_class(struct thread *td, int class)
832 THREAD_LOCK_ASSERT(td, MA_OWNED);
833 td->td_pri_class = class;
837 * Adjust the priority of a thread.
840 sched_priority(struct thread *td, u_char prio)
844 KTR_POINT3(KTR_SCHED, "thread", sched_tdname(td), "priority change",
845 "prio:%d", td->td_priority, "new prio:%d", prio, KTR_ATTR_LINKED,
846 sched_tdname(curthread));
847 SDT_PROBE3(sched, , , change__pri, td, td->td_proc, prio);
848 if (td != curthread && prio > td->td_priority) {
849 KTR_POINT3(KTR_SCHED, "thread", sched_tdname(curthread),
850 "lend prio", "prio:%d", td->td_priority, "new prio:%d",
851 prio, KTR_ATTR_LINKED, sched_tdname(td));
852 SDT_PROBE4(sched, , , lend__pri, td, td->td_proc, prio,
855 THREAD_LOCK_ASSERT(td, MA_OWNED);
856 if (td->td_priority == prio)
858 td->td_priority = prio;
859 if (TD_ON_RUNQ(td) && td->td_rqindex != (prio / RQ_PPQ)) {
861 sched_add(td, SRQ_BORING);
866 * Update a thread's priority when it is lent another thread's
870 sched_lend_prio(struct thread *td, u_char prio)
873 td->td_flags |= TDF_BORROWING;
874 sched_priority(td, prio);
878 * Restore a thread's priority when priority propagation is
879 * over. The prio argument is the minimum priority the thread
880 * needs to have to satisfy other possible priority lending
881 * requests. If the thread's regulary priority is less
882 * important than prio the thread will keep a priority boost
886 sched_unlend_prio(struct thread *td, u_char prio)
890 if (td->td_base_pri >= PRI_MIN_TIMESHARE &&
891 td->td_base_pri <= PRI_MAX_TIMESHARE)
892 base_pri = td->td_user_pri;
894 base_pri = td->td_base_pri;
895 if (prio >= base_pri) {
896 td->td_flags &= ~TDF_BORROWING;
897 sched_prio(td, base_pri);
899 sched_lend_prio(td, prio);
903 sched_prio(struct thread *td, u_char prio)
907 /* First, update the base priority. */
908 td->td_base_pri = prio;
911 * If the thread is borrowing another thread's priority, don't ever
912 * lower the priority.
914 if (td->td_flags & TDF_BORROWING && td->td_priority < prio)
917 /* Change the real priority. */
918 oldprio = td->td_priority;
919 sched_priority(td, prio);
922 * If the thread is on a turnstile, then let the turnstile update
925 if (TD_ON_LOCK(td) && oldprio != prio)
926 turnstile_adjust(td, oldprio);
930 sched_user_prio(struct thread *td, u_char prio)
933 THREAD_LOCK_ASSERT(td, MA_OWNED);
934 td->td_base_user_pri = prio;
935 if (td->td_lend_user_pri <= prio)
937 td->td_user_pri = prio;
941 sched_lend_user_prio(struct thread *td, u_char prio)
944 THREAD_LOCK_ASSERT(td, MA_OWNED);
945 td->td_lend_user_pri = prio;
946 td->td_user_pri = min(prio, td->td_base_user_pri);
947 if (td->td_priority > td->td_user_pri)
948 sched_prio(td, td->td_user_pri);
949 else if (td->td_priority != td->td_user_pri)
950 td->td_flags |= TDF_NEEDRESCHED;
954 sched_sleep(struct thread *td, int pri)
957 THREAD_LOCK_ASSERT(td, MA_OWNED);
958 td->td_slptick = ticks;
959 td_get_sched(td)->ts_slptime = 0;
960 if (pri != 0 && PRI_BASE(td->td_pri_class) == PRI_TIMESHARE)
962 if (TD_IS_SUSPENDED(td) || pri >= PSOCK)
963 td->td_flags |= TDF_CANSWAP;
967 sched_switch(struct thread *td, struct thread *newtd, int flags)
975 ts = td_get_sched(td);
978 THREAD_LOCK_ASSERT(td, MA_OWNED);
981 * Switch to the sched lock to fix things up and pick
983 * Block the td_lock in order to avoid breaking the critical path.
985 if (td->td_lock != &sched_lock) {
986 mtx_lock_spin(&sched_lock);
987 tmtx = thread_lock_block(td);
990 if ((td->td_flags & TDF_NOLOAD) == 0)
993 td->td_lastcpu = td->td_oncpu;
994 preempted = !((td->td_flags & TDF_SLICEEND) ||
995 (flags & SWT_RELINQUISH));
996 td->td_flags &= ~(TDF_NEEDRESCHED | TDF_SLICEEND);
997 td->td_owepreempt = 0;
998 td->td_oncpu = NOCPU;
1001 * At the last moment, if this thread is still marked RUNNING,
1002 * then put it back on the run queue as it has not been suspended
1003 * or stopped or any thing else similar. We never put the idle
1004 * threads on the run queue, however.
1006 if (td->td_flags & TDF_IDLETD) {
1009 CPU_CLR(PCPU_GET(cpuid), &idle_cpus_mask);
1012 if (TD_IS_RUNNING(td)) {
1013 /* Put us back on the run queue. */
1014 sched_add(td, preempted ?
1015 SRQ_OURSELF|SRQ_YIELDING|SRQ_PREEMPTED :
1016 SRQ_OURSELF|SRQ_YIELDING);
1021 * The thread we are about to run needs to be counted
1022 * as if it had been added to the run queue and selected.
1028 KASSERT((newtd->td_inhibitors == 0),
1029 ("trying to run inhibited thread"));
1030 newtd->td_flags |= TDF_DIDRUN;
1031 TD_SET_RUNNING(newtd);
1032 if ((newtd->td_flags & TDF_NOLOAD) == 0)
1035 newtd = choosethread();
1036 MPASS(newtd->td_lock == &sched_lock);
1041 if (PMC_PROC_IS_USING_PMCS(td->td_proc))
1042 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_OUT);
1045 SDT_PROBE2(sched, , , off__cpu, newtd, newtd->td_proc);
1048 lock_profile_release_lock(&sched_lock.lock_object);
1049 #ifdef KDTRACE_HOOKS
1051 * If DTrace has set the active vtime enum to anything
1052 * other than INACTIVE (0), then it should have set the
1055 if (dtrace_vtime_active)
1056 (*dtrace_vtime_switch_func)(newtd);
1059 cpu_switch(td, newtd, tmtx != NULL ? tmtx : td->td_lock);
1060 lock_profile_obtain_lock_success(&sched_lock.lock_object,
1061 0, 0, __FILE__, __LINE__);
1063 * Where am I? What year is it?
1064 * We are in the same thread that went to sleep above,
1065 * but any amount of time may have passed. All our context
1066 * will still be available as will local variables.
1067 * PCPU values however may have changed as we may have
1068 * changed CPU so don't trust cached values of them.
1069 * New threads will go to fork_exit() instead of here
1070 * so if you change things here you may need to change
1073 * If the thread above was exiting it will never wake
1074 * up again here, so either it has saved everything it
1075 * needed to, or the thread_wait() or wait() will
1079 SDT_PROBE0(sched, , , on__cpu);
1081 if (PMC_PROC_IS_USING_PMCS(td->td_proc))
1082 PMC_SWITCH_CONTEXT(td, PMC_FN_CSW_IN);
1085 SDT_PROBE0(sched, , , remain__cpu);
1088 if (td->td_flags & TDF_IDLETD)
1089 CPU_SET(PCPU_GET(cpuid), &idle_cpus_mask);
1091 sched_lock.mtx_lock = (uintptr_t)td;
1092 td->td_oncpu = PCPU_GET(cpuid);
1093 MPASS(td->td_lock == &sched_lock);
1097 sched_wakeup(struct thread *td)
1099 struct td_sched *ts;
1101 THREAD_LOCK_ASSERT(td, MA_OWNED);
1102 ts = td_get_sched(td);
1103 td->td_flags &= ~TDF_CANSWAP;
1104 if (ts->ts_slptime > 1) {
1110 ts->ts_slice = sched_slice;
1111 sched_add(td, SRQ_BORING);
1116 forward_wakeup(int cpunum)
1119 cpuset_t dontuse, map, map2;
1123 mtx_assert(&sched_lock, MA_OWNED);
1125 CTR0(KTR_RUNQ, "forward_wakeup()");
1127 if ((!forward_wakeup_enabled) ||
1128 (forward_wakeup_use_mask == 0 && forward_wakeup_use_loop == 0))
1130 if (!smp_started || cold || panicstr)
1133 forward_wakeups_requested++;
1136 * Check the idle mask we received against what we calculated
1137 * before in the old version.
1139 me = PCPU_GET(cpuid);
1141 /* Don't bother if we should be doing it ourself. */
1142 if (CPU_ISSET(me, &idle_cpus_mask) &&
1143 (cpunum == NOCPU || me == cpunum))
1146 CPU_SETOF(me, &dontuse);
1147 CPU_OR(&dontuse, &stopped_cpus);
1148 CPU_OR(&dontuse, &hlt_cpus_mask);
1150 if (forward_wakeup_use_loop) {
1151 STAILQ_FOREACH(pc, &cpuhead, pc_allcpu) {
1153 if (!CPU_ISSET(id, &dontuse) &&
1154 pc->pc_curthread == pc->pc_idlethread) {
1160 if (forward_wakeup_use_mask) {
1161 map = idle_cpus_mask;
1162 CPU_NAND(&map, &dontuse);
1164 /* If they are both on, compare and use loop if different. */
1165 if (forward_wakeup_use_loop) {
1166 if (CPU_CMP(&map, &map2)) {
1167 printf("map != map2, loop method preferred\n");
1175 /* If we only allow a specific CPU, then mask off all the others. */
1176 if (cpunum != NOCPU) {
1177 KASSERT((cpunum <= mp_maxcpus),("forward_wakeup: bad cpunum."));
1178 iscpuset = CPU_ISSET(cpunum, &map);
1182 CPU_SETOF(cpunum, &map);
1184 if (!CPU_EMPTY(&map)) {
1185 forward_wakeups_delivered++;
1186 STAILQ_FOREACH(pc, &cpuhead, pc_allcpu) {
1188 if (!CPU_ISSET(id, &map))
1190 if (cpu_idle_wakeup(pc->pc_cpuid))
1193 if (!CPU_EMPTY(&map))
1194 ipi_selected(map, IPI_AST);
1197 if (cpunum == NOCPU)
1198 printf("forward_wakeup: Idle processor not found\n");
1203 kick_other_cpu(int pri, int cpuid)
1208 pcpu = pcpu_find(cpuid);
1209 if (CPU_ISSET(cpuid, &idle_cpus_mask)) {
1210 forward_wakeups_delivered++;
1211 if (!cpu_idle_wakeup(cpuid))
1212 ipi_cpu(cpuid, IPI_AST);
1216 cpri = pcpu->pc_curthread->td_priority;
1220 #if defined(IPI_PREEMPTION) && defined(PREEMPTION)
1221 #if !defined(FULL_PREEMPTION)
1222 if (pri <= PRI_MAX_ITHD)
1223 #endif /* ! FULL_PREEMPTION */
1225 ipi_cpu(cpuid, IPI_PREEMPT);
1228 #endif /* defined(IPI_PREEMPTION) && defined(PREEMPTION) */
1230 pcpu->pc_curthread->td_flags |= TDF_NEEDRESCHED;
1231 ipi_cpu(cpuid, IPI_AST);
1238 sched_pickcpu(struct thread *td)
1242 mtx_assert(&sched_lock, MA_OWNED);
1244 if (td->td_lastcpu != NOCPU && THREAD_CAN_SCHED(td, td->td_lastcpu))
1245 best = td->td_lastcpu;
1249 if (!THREAD_CAN_SCHED(td, cpu))
1254 else if (runq_length[cpu] < runq_length[best])
1257 KASSERT(best != NOCPU, ("no valid CPUs"));
1264 sched_add(struct thread *td, int flags)
1268 struct td_sched *ts;
1273 ts = td_get_sched(td);
1274 THREAD_LOCK_ASSERT(td, MA_OWNED);
1275 KASSERT((td->td_inhibitors == 0),
1276 ("sched_add: trying to run inhibited thread"));
1277 KASSERT((TD_CAN_RUN(td) || TD_IS_RUNNING(td)),
1278 ("sched_add: bad thread state"));
1279 KASSERT(td->td_flags & TDF_INMEM,
1280 ("sched_add: thread swapped out"));
1282 KTR_STATE2(KTR_SCHED, "thread", sched_tdname(td), "runq add",
1283 "prio:%d", td->td_priority, KTR_ATTR_LINKED,
1284 sched_tdname(curthread));
1285 KTR_POINT1(KTR_SCHED, "thread", sched_tdname(curthread), "wokeup",
1286 KTR_ATTR_LINKED, sched_tdname(td));
1287 SDT_PROBE4(sched, , , enqueue, td, td->td_proc, NULL,
1288 flags & SRQ_PREEMPTED);
1292 * Now that the thread is moving to the run-queue, set the lock
1293 * to the scheduler's lock.
1295 if (td->td_lock != &sched_lock) {
1296 mtx_lock_spin(&sched_lock);
1297 thread_lock_set(td, &sched_lock);
1302 * If SMP is started and the thread is pinned or otherwise limited to
1303 * a specific set of CPUs, queue the thread to a per-CPU run queue.
1304 * Otherwise, queue the thread to the global run queue.
1306 * If SMP has not yet been started we must use the global run queue
1307 * as per-CPU state may not be initialized yet and we may crash if we
1308 * try to access the per-CPU run queues.
1310 if (smp_started && (td->td_pinned != 0 || td->td_flags & TDF_BOUND ||
1311 ts->ts_flags & TSF_AFFINITY)) {
1312 if (td->td_pinned != 0)
1313 cpu = td->td_lastcpu;
1314 else if (td->td_flags & TDF_BOUND) {
1315 /* Find CPU from bound runq. */
1316 KASSERT(SKE_RUNQ_PCPU(ts),
1317 ("sched_add: bound td_sched not on cpu runq"));
1318 cpu = ts->ts_runq - &runq_pcpu[0];
1320 /* Find a valid CPU for our cpuset */
1321 cpu = sched_pickcpu(td);
1322 ts->ts_runq = &runq_pcpu[cpu];
1325 "sched_add: Put td_sched:%p(td:%p) on cpu%d runq", ts, td,
1329 "sched_add: adding td_sched:%p (td:%p) to gbl runq", ts,
1332 ts->ts_runq = &runq;
1335 cpuid = PCPU_GET(cpuid);
1336 if (single_cpu && cpu != cpuid) {
1337 kick_other_cpu(td->td_priority, cpu);
1340 tidlemsk = idle_cpus_mask;
1341 CPU_NAND(&tidlemsk, &hlt_cpus_mask);
1342 CPU_CLR(cpuid, &tidlemsk);
1344 if (!CPU_ISSET(cpuid, &idle_cpus_mask) &&
1345 ((flags & SRQ_INTR) == 0) &&
1346 !CPU_EMPTY(&tidlemsk))
1347 forwarded = forward_wakeup(cpu);
1351 if ((flags & SRQ_YIELDING) == 0 && maybe_preempt(td))
1358 if ((td->td_flags & TDF_NOLOAD) == 0)
1360 runq_add(ts->ts_runq, td, flags);
1366 struct td_sched *ts;
1368 ts = td_get_sched(td);
1369 THREAD_LOCK_ASSERT(td, MA_OWNED);
1370 KASSERT((td->td_inhibitors == 0),
1371 ("sched_add: trying to run inhibited thread"));
1372 KASSERT((TD_CAN_RUN(td) || TD_IS_RUNNING(td)),
1373 ("sched_add: bad thread state"));
1374 KASSERT(td->td_flags & TDF_INMEM,
1375 ("sched_add: thread swapped out"));
1376 KTR_STATE2(KTR_SCHED, "thread", sched_tdname(td), "runq add",
1377 "prio:%d", td->td_priority, KTR_ATTR_LINKED,
1378 sched_tdname(curthread));
1379 KTR_POINT1(KTR_SCHED, "thread", sched_tdname(curthread), "wokeup",
1380 KTR_ATTR_LINKED, sched_tdname(td));
1381 SDT_PROBE4(sched, , , enqueue, td, td->td_proc, NULL,
1382 flags & SRQ_PREEMPTED);
1385 * Now that the thread is moving to the run-queue, set the lock
1386 * to the scheduler's lock.
1388 if (td->td_lock != &sched_lock) {
1389 mtx_lock_spin(&sched_lock);
1390 thread_lock_set(td, &sched_lock);
1393 CTR2(KTR_RUNQ, "sched_add: adding td_sched:%p (td:%p) to runq", ts, td);
1394 ts->ts_runq = &runq;
1397 * If we are yielding (on the way out anyhow) or the thread
1398 * being saved is US, then don't try be smart about preemption
1399 * or kicking off another CPU as it won't help and may hinder.
1400 * In the YIEDLING case, we are about to run whoever is being
1401 * put in the queue anyhow, and in the OURSELF case, we are
1402 * putting ourself on the run queue which also only happens
1403 * when we are about to yield.
1405 if ((flags & SRQ_YIELDING) == 0) {
1406 if (maybe_preempt(td))
1409 if ((td->td_flags & TDF_NOLOAD) == 0)
1411 runq_add(ts->ts_runq, td, flags);
1417 sched_rem(struct thread *td)
1419 struct td_sched *ts;
1421 ts = td_get_sched(td);
1422 KASSERT(td->td_flags & TDF_INMEM,
1423 ("sched_rem: thread swapped out"));
1424 KASSERT(TD_ON_RUNQ(td),
1425 ("sched_rem: thread not on run queue"));
1426 mtx_assert(&sched_lock, MA_OWNED);
1427 KTR_STATE2(KTR_SCHED, "thread", sched_tdname(td), "runq rem",
1428 "prio:%d", td->td_priority, KTR_ATTR_LINKED,
1429 sched_tdname(curthread));
1430 SDT_PROBE3(sched, , , dequeue, td, td->td_proc, NULL);
1432 if ((td->td_flags & TDF_NOLOAD) == 0)
1435 if (ts->ts_runq != &runq)
1436 runq_length[ts->ts_runq - runq_pcpu]--;
1438 runq_remove(ts->ts_runq, td);
1443 * Select threads to run. Note that running threads still consume a
1452 mtx_assert(&sched_lock, MA_OWNED);
1454 struct thread *tdcpu;
1457 td = runq_choose_fuzz(&runq, runq_fuzz);
1458 tdcpu = runq_choose(&runq_pcpu[PCPU_GET(cpuid)]);
1462 tdcpu->td_priority < td->td_priority)) {
1463 CTR2(KTR_RUNQ, "choosing td %p from pcpu runq %d", tdcpu,
1466 rq = &runq_pcpu[PCPU_GET(cpuid)];
1468 CTR1(KTR_RUNQ, "choosing td_sched %p from main runq", td);
1473 td = runq_choose(&runq);
1479 runq_length[PCPU_GET(cpuid)]--;
1481 runq_remove(rq, td);
1482 td->td_flags |= TDF_DIDRUN;
1484 KASSERT(td->td_flags & TDF_INMEM,
1485 ("sched_choose: thread swapped out"));
1488 return (PCPU_GET(idlethread));
1492 sched_preempt(struct thread *td)
1495 SDT_PROBE2(sched, , , surrender, td, td->td_proc);
1497 if (td->td_critnest > 1)
1498 td->td_owepreempt = 1;
1500 mi_switch(SW_INVOL | SW_PREEMPT | SWT_PREEMPT, NULL);
1505 sched_userret(struct thread *td)
1508 * XXX we cheat slightly on the locking here to avoid locking in
1509 * the usual case. Setting td_priority here is essentially an
1510 * incomplete workaround for not setting it properly elsewhere.
1511 * Now that some interrupt handlers are threads, not setting it
1512 * properly elsewhere can clobber it in the window between setting
1513 * it here and returning to user mode, so don't waste time setting
1514 * it perfectly here.
1516 KASSERT((td->td_flags & TDF_BORROWING) == 0,
1517 ("thread with borrowed priority returning to userland"));
1518 if (td->td_priority != td->td_user_pri) {
1520 td->td_priority = td->td_user_pri;
1521 td->td_base_pri = td->td_user_pri;
1527 sched_bind(struct thread *td, int cpu)
1529 struct td_sched *ts;
1531 THREAD_LOCK_ASSERT(td, MA_OWNED|MA_NOTRECURSED);
1532 KASSERT(td == curthread, ("sched_bind: can only bind curthread"));
1534 ts = td_get_sched(td);
1536 td->td_flags |= TDF_BOUND;
1538 ts->ts_runq = &runq_pcpu[cpu];
1539 if (PCPU_GET(cpuid) == cpu)
1542 mi_switch(SW_VOL, NULL);
1547 sched_unbind(struct thread* td)
1549 THREAD_LOCK_ASSERT(td, MA_OWNED);
1550 KASSERT(td == curthread, ("sched_unbind: can only bind curthread"));
1551 td->td_flags &= ~TDF_BOUND;
1555 sched_is_bound(struct thread *td)
1557 THREAD_LOCK_ASSERT(td, MA_OWNED);
1558 return (td->td_flags & TDF_BOUND);
1562 sched_relinquish(struct thread *td)
1565 mi_switch(SW_VOL | SWT_RELINQUISH, NULL);
1572 return (sched_tdcnt);
1576 sched_sizeof_proc(void)
1578 return (sizeof(struct proc));
1582 sched_sizeof_thread(void)
1584 return (sizeof(struct thread) + sizeof(struct td_sched));
1588 sched_pctcpu(struct thread *td)
1590 struct td_sched *ts;
1592 THREAD_LOCK_ASSERT(td, MA_OWNED);
1593 ts = td_get_sched(td);
1594 return (ts->ts_pctcpu);
1599 * Calculates the contribution to the thread cpu usage for the latest
1600 * (unfinished) second.
1603 sched_pctcpu_delta(struct thread *td)
1605 struct td_sched *ts;
1609 THREAD_LOCK_ASSERT(td, MA_OWNED);
1610 ts = td_get_sched(td);
1612 realstathz = stathz ? stathz : hz;
1613 if (ts->ts_cpticks != 0) {
1614 #if (FSHIFT >= CCPU_SHIFT)
1615 delta = (realstathz == 100)
1616 ? ((fixpt_t) ts->ts_cpticks) <<
1617 (FSHIFT - CCPU_SHIFT) :
1618 100 * (((fixpt_t) ts->ts_cpticks)
1619 << (FSHIFT - CCPU_SHIFT)) / realstathz;
1621 delta = ((FSCALE - ccpu) *
1623 FSCALE / realstathz)) >> FSHIFT;
1632 sched_estcpu(struct thread *td)
1635 return (td_get_sched(td)->ts_estcpu);
1639 * The actual idle process.
1642 sched_idletd(void *dummy)
1644 struct pcpuidlestat *stat;
1646 THREAD_NO_SLEEPING();
1647 stat = DPCPU_PTR(idlestat);
1649 mtx_assert(&Giant, MA_NOTOWNED);
1651 while (sched_runnable() == 0) {
1652 cpu_idle(stat->idlecalls + stat->oldidlecalls > 64);
1656 mtx_lock_spin(&sched_lock);
1657 mi_switch(SW_VOL | SWT_IDLE, NULL);
1658 mtx_unlock_spin(&sched_lock);
1663 * A CPU is entering for the first time or a thread is exiting.
1666 sched_throw(struct thread *td)
1669 * Correct spinlock nesting. The idle thread context that we are
1670 * borrowing was created so that it would start out with a single
1671 * spin lock (sched_lock) held in fork_trampoline(). Since we've
1672 * explicitly acquired locks in this function, the nesting count
1673 * is now 2 rather than 1. Since we are nested, calling
1674 * spinlock_exit() will simply adjust the counts without allowing
1675 * spin lock using code to interrupt us.
1678 mtx_lock_spin(&sched_lock);
1680 PCPU_SET(switchtime, cpu_ticks());
1681 PCPU_SET(switchticks, ticks);
1683 lock_profile_release_lock(&sched_lock.lock_object);
1684 MPASS(td->td_lock == &sched_lock);
1685 td->td_lastcpu = td->td_oncpu;
1686 td->td_oncpu = NOCPU;
1688 mtx_assert(&sched_lock, MA_OWNED);
1689 KASSERT(curthread->td_md.md_spinlock_count == 1, ("invalid count"));
1690 cpu_throw(td, choosethread()); /* doesn't return */
1694 sched_fork_exit(struct thread *td)
1698 * Finish setting up thread glue so that it begins execution in a
1699 * non-nested critical section with sched_lock held but not recursed.
1701 td->td_oncpu = PCPU_GET(cpuid);
1702 sched_lock.mtx_lock = (uintptr_t)td;
1703 lock_profile_obtain_lock_success(&sched_lock.lock_object,
1704 0, 0, __FILE__, __LINE__);
1705 THREAD_LOCK_ASSERT(td, MA_OWNED | MA_NOTRECURSED);
1709 sched_tdname(struct thread *td)
1712 struct td_sched *ts;
1714 ts = td_get_sched(td);
1715 if (ts->ts_name[0] == '\0')
1716 snprintf(ts->ts_name, sizeof(ts->ts_name),
1717 "%s tid %d", td->td_name, td->td_tid);
1718 return (ts->ts_name);
1720 return (td->td_name);
1726 sched_clear_tdname(struct thread *td)
1728 struct td_sched *ts;
1730 ts = td_get_sched(td);
1731 ts->ts_name[0] = '\0';
1736 sched_affinity(struct thread *td)
1739 struct td_sched *ts;
1742 THREAD_LOCK_ASSERT(td, MA_OWNED);
1745 * Set the TSF_AFFINITY flag if there is at least one CPU this
1746 * thread can't run on.
1748 ts = td_get_sched(td);
1749 ts->ts_flags &= ~TSF_AFFINITY;
1751 if (!THREAD_CAN_SCHED(td, cpu)) {
1752 ts->ts_flags |= TSF_AFFINITY;
1758 * If this thread can run on all CPUs, nothing else to do.
1760 if (!(ts->ts_flags & TSF_AFFINITY))
1763 /* Pinned threads and bound threads should be left alone. */
1764 if (td->td_pinned != 0 || td->td_flags & TDF_BOUND)
1767 switch (td->td_state) {
1770 * If we are on a per-CPU runqueue that is in the set,
1771 * then nothing needs to be done.
1773 if (ts->ts_runq != &runq &&
1774 THREAD_CAN_SCHED(td, ts->ts_runq - runq_pcpu))
1777 /* Put this thread on a valid per-CPU runqueue. */
1779 sched_add(td, SRQ_BORING);
1783 * See if our current CPU is in the set. If not, force a
1786 if (THREAD_CAN_SCHED(td, td->td_oncpu))
1789 td->td_flags |= TDF_NEEDRESCHED;
1790 if (td != curthread)
1791 ipi_cpu(cpu, IPI_AST);