sched_ule.c revision 123231
1109864Sjeff/*-
2113357Sjeff * Copyright (c) 2002-2003, Jeffrey Roberson <jeff@freebsd.org>
3109864Sjeff * All rights reserved.
4109864Sjeff *
5109864Sjeff * Redistribution and use in source and binary forms, with or without
6109864Sjeff * modification, are permitted provided that the following conditions
7109864Sjeff * are met:
8109864Sjeff * 1. Redistributions of source code must retain the above copyright
9109864Sjeff *    notice unmodified, this list of conditions, and the following
10109864Sjeff *    disclaimer.
11109864Sjeff * 2. Redistributions in binary form must reproduce the above copyright
12109864Sjeff *    notice, this list of conditions and the following disclaimer in the
13109864Sjeff *    documentation and/or other materials provided with the distribution.
14109864Sjeff *
15109864Sjeff * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16109864Sjeff * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17109864Sjeff * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18109864Sjeff * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19109864Sjeff * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20109864Sjeff * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21109864Sjeff * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22109864Sjeff * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23109864Sjeff * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24109864Sjeff * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25109864Sjeff */
26109864Sjeff
27116182Sobrien#include <sys/cdefs.h>
28116182Sobrien__FBSDID("$FreeBSD: head/sys/kern/sched_ule.c 123231 2003-12-07 09:57:51Z peter $");
29116182Sobrien
30109864Sjeff#include <sys/param.h>
31109864Sjeff#include <sys/systm.h>
32109864Sjeff#include <sys/kernel.h>
33109864Sjeff#include <sys/ktr.h>
34109864Sjeff#include <sys/lock.h>
35109864Sjeff#include <sys/mutex.h>
36109864Sjeff#include <sys/proc.h>
37112966Sjeff#include <sys/resource.h>
38122038Sjeff#include <sys/resourcevar.h>
39109864Sjeff#include <sys/sched.h>
40109864Sjeff#include <sys/smp.h>
41109864Sjeff#include <sys/sx.h>
42109864Sjeff#include <sys/sysctl.h>
43109864Sjeff#include <sys/sysproto.h>
44109864Sjeff#include <sys/vmmeter.h>
45109864Sjeff#ifdef DDB
46109864Sjeff#include <ddb/ddb.h>
47109864Sjeff#endif
48109864Sjeff#ifdef KTRACE
49109864Sjeff#include <sys/uio.h>
50109864Sjeff#include <sys/ktrace.h>
51109864Sjeff#endif
52109864Sjeff
53109864Sjeff#include <machine/cpu.h>
54121790Sjeff#include <machine/smp.h>
55109864Sjeff
56113357Sjeff#define KTR_ULE         KTR_NFS
57113357Sjeff
58109864Sjeff/* decay 95% of `p_pctcpu' in 60 seconds; see CCPU_SHIFT before changing */
59109864Sjeff/* XXX This is bogus compatability crap for ps */
60109864Sjeffstatic fixpt_t  ccpu = 0.95122942450071400909 * FSCALE; /* exp(-1/20) */
61109864SjeffSYSCTL_INT(_kern, OID_AUTO, ccpu, CTLFLAG_RD, &ccpu, 0, "");
62109864Sjeff
63109864Sjeffstatic void sched_setup(void *dummy);
64109864SjeffSYSINIT(sched_setup, SI_SUB_RUN_QUEUE, SI_ORDER_FIRST, sched_setup, NULL)
65109864Sjeff
66113357Sjeffstatic SYSCTL_NODE(_kern, OID_AUTO, sched, CTLFLAG_RW, 0, "SCHED");
67113357Sjeff
68113357Sjeffstatic int sched_strict;
69113357SjeffSYSCTL_INT(_kern_sched, OID_AUTO, strict, CTLFLAG_RD, &sched_strict, 0, "");
70113357Sjeff
71113357Sjeffstatic int slice_min = 1;
72113357SjeffSYSCTL_INT(_kern_sched, OID_AUTO, slice_min, CTLFLAG_RW, &slice_min, 0, "");
73113357Sjeff
74116365Sjeffstatic int slice_max = 10;
75113357SjeffSYSCTL_INT(_kern_sched, OID_AUTO, slice_max, CTLFLAG_RW, &slice_max, 0, "");
76113357Sjeff
77111857Sjeffint realstathz;
78113357Sjeffint tickincr = 1;
79111857Sjeff
80116069Sjeff#ifdef SMP
81116069Sjeff/* Callout to handle load balancing SMP systems. */
82116069Sjeffstatic struct callout kseq_lb_callout;
83116069Sjeff#endif
84116069Sjeff
85109864Sjeff/*
86109864Sjeff * These datastructures are allocated within their parent datastructure but
87109864Sjeff * are scheduler specific.
88109864Sjeff */
89109864Sjeff
90109864Sjeffstruct ke_sched {
91109864Sjeff	int		ske_slice;
92109864Sjeff	struct runq	*ske_runq;
93109864Sjeff	/* The following variables are only used for pctcpu calculation */
94109864Sjeff	int		ske_ltick;	/* Last tick that we were running on */
95109864Sjeff	int		ske_ftick;	/* First tick that we were running on */
96109864Sjeff	int		ske_ticks;	/* Tick count */
97113357Sjeff	/* CPU that we have affinity for. */
98110260Sjeff	u_char		ske_cpu;
99109864Sjeff};
100109864Sjeff#define	ke_slice	ke_sched->ske_slice
101109864Sjeff#define	ke_runq		ke_sched->ske_runq
102109864Sjeff#define	ke_ltick	ke_sched->ske_ltick
103109864Sjeff#define	ke_ftick	ke_sched->ske_ftick
104109864Sjeff#define	ke_ticks	ke_sched->ske_ticks
105110260Sjeff#define	ke_cpu		ke_sched->ske_cpu
106121790Sjeff#define	ke_assign	ke_procq.tqe_next
107109864Sjeff
108121790Sjeff#define	KEF_ASSIGNED	KEF_SCHED0	/* KSE is being migrated. */
109122158Sjeff#define	KEF_BOUND	KEF_SCHED1	/* KSE can not migrate. */
110121790Sjeff
111109864Sjeffstruct kg_sched {
112110645Sjeff	int	skg_slptime;		/* Number of ticks we vol. slept */
113110645Sjeff	int	skg_runtime;		/* Number of ticks we were running */
114109864Sjeff};
115109864Sjeff#define	kg_slptime	kg_sched->skg_slptime
116110645Sjeff#define	kg_runtime	kg_sched->skg_runtime
117109864Sjeff
118109864Sjeffstruct td_sched {
119109864Sjeff	int	std_slptime;
120109864Sjeff};
121109864Sjeff#define	td_slptime	td_sched->std_slptime
122109864Sjeff
123110267Sjeffstruct td_sched td_sched;
124109864Sjeffstruct ke_sched ke_sched;
125109864Sjeffstruct kg_sched kg_sched;
126109864Sjeff
127109864Sjeffstruct ke_sched *kse0_sched = &ke_sched;
128109864Sjeffstruct kg_sched *ksegrp0_sched = &kg_sched;
129109864Sjeffstruct p_sched *proc0_sched = NULL;
130109864Sjeffstruct td_sched *thread0_sched = &td_sched;
131109864Sjeff
132109864Sjeff/*
133116642Sjeff * The priority is primarily determined by the interactivity score.  Thus, we
134116642Sjeff * give lower(better) priorities to kse groups that use less CPU.  The nice
135116642Sjeff * value is then directly added to this to allow nice to have some effect
136116642Sjeff * on latency.
137111857Sjeff *
138111857Sjeff * PRI_RANGE:	Total priority range for timeshare threads.
139116642Sjeff * PRI_NRESV:	Number of nice values.
140111857Sjeff * PRI_BASE:	The start of the dynamic range.
141109864Sjeff */
142111857Sjeff#define	SCHED_PRI_RANGE		(PRI_MAX_TIMESHARE - PRI_MIN_TIMESHARE + 1)
143121869Sjeff#define	SCHED_PRI_NRESV		((PRIO_MAX - PRIO_MIN) + 1)
144121869Sjeff#define	SCHED_PRI_NHALF		(SCHED_PRI_NRESV / 2)
145116642Sjeff#define	SCHED_PRI_BASE		(PRI_MIN_TIMESHARE)
146113357Sjeff#define	SCHED_PRI_INTERACT(score)					\
147116642Sjeff    ((score) * SCHED_PRI_RANGE / SCHED_INTERACT_MAX)
148109864Sjeff
149109864Sjeff/*
150111857Sjeff * These determine the interactivity of a process.
151109864Sjeff *
152110645Sjeff * SLP_RUN_MAX:	Maximum amount of sleep time + run time we'll accumulate
153110645Sjeff *		before throttling back.
154121868Sjeff * SLP_RUN_FORK:	Maximum slp+run time to inherit at fork time.
155116365Sjeff * INTERACT_MAX:	Maximum interactivity value.  Smaller is better.
156111857Sjeff * INTERACT_THRESH:	Threshhold for placement on the current runq.
157109864Sjeff */
158121126Sjeff#define	SCHED_SLP_RUN_MAX	((hz * 5) << 10)
159121868Sjeff#define	SCHED_SLP_RUN_FORK	((hz / 2) << 10)
160116365Sjeff#define	SCHED_INTERACT_MAX	(100)
161116365Sjeff#define	SCHED_INTERACT_HALF	(SCHED_INTERACT_MAX / 2)
162121126Sjeff#define	SCHED_INTERACT_THRESH	(30)
163111857Sjeff
164109864Sjeff/*
165109864Sjeff * These parameters and macros determine the size of the time slice that is
166109864Sjeff * granted to each thread.
167109864Sjeff *
168109864Sjeff * SLICE_MIN:	Minimum time slice granted, in units of ticks.
169109864Sjeff * SLICE_MAX:	Maximum time slice granted.
170109864Sjeff * SLICE_RANGE:	Range of available time slices scaled by hz.
171112966Sjeff * SLICE_SCALE:	The number slices granted per val in the range of [0, max].
172112966Sjeff * SLICE_NICE:  Determine the amount of slice granted to a scaled nice.
173121871Sjeff * SLICE_NTHRESH:	The nice cutoff point for slice assignment.
174109864Sjeff */
175113357Sjeff#define	SCHED_SLICE_MIN			(slice_min)
176113357Sjeff#define	SCHED_SLICE_MAX			(slice_max)
177121871Sjeff#define	SCHED_SLICE_NTHRESH	(SCHED_PRI_NHALF - 1)
178111857Sjeff#define	SCHED_SLICE_RANGE		(SCHED_SLICE_MAX - SCHED_SLICE_MIN + 1)
179109864Sjeff#define	SCHED_SLICE_SCALE(val, max)	(((val) * SCHED_SLICE_RANGE) / (max))
180112966Sjeff#define	SCHED_SLICE_NICE(nice)						\
181121871Sjeff    (SCHED_SLICE_MAX - SCHED_SLICE_SCALE((nice), SCHED_SLICE_NTHRESH))
182109864Sjeff
183109864Sjeff/*
184109864Sjeff * This macro determines whether or not the kse belongs on the current or
185109864Sjeff * next run queue.
186109864Sjeff */
187113357Sjeff#define	SCHED_INTERACTIVE(kg)						\
188113357Sjeff    (sched_interact_score(kg) < SCHED_INTERACT_THRESH)
189113417Sjeff#define	SCHED_CURR(kg, ke)						\
190121107Sjeff    (ke->ke_thread->td_priority != kg->kg_user_pri ||			\
191121107Sjeff    SCHED_INTERACTIVE(kg))
192109864Sjeff
193109864Sjeff/*
194109864Sjeff * Cpu percentage computation macros and defines.
195109864Sjeff *
196109864Sjeff * SCHED_CPU_TIME:	Number of seconds to average the cpu usage across.
197109864Sjeff * SCHED_CPU_TICKS:	Number of hz ticks to average the cpu usage across.
198109864Sjeff */
199109864Sjeff
200112971Sjeff#define	SCHED_CPU_TIME	10
201109864Sjeff#define	SCHED_CPU_TICKS	(hz * SCHED_CPU_TIME)
202109864Sjeff
203109864Sjeff/*
204113357Sjeff * kseq - per processor runqs and statistics.
205109864Sjeff */
206109864Sjeff
207113357Sjeff#define	KSEQ_NCLASS	(PRI_IDLE + 1)	/* Number of run classes. */
208113357Sjeff
209109864Sjeffstruct kseq {
210113357Sjeff	struct runq	ksq_idle;		/* Queue of IDLE threads. */
211113357Sjeff	struct runq	ksq_timeshare[2];	/* Run queues for !IDLE. */
212113357Sjeff	struct runq	*ksq_next;		/* Next timeshare queue. */
213113357Sjeff	struct runq	*ksq_curr;		/* Current queue. */
214121896Sjeff	int		ksq_load_timeshare;	/* Load for timeshare. */
215113357Sjeff	int		ksq_load;		/* Aggregate load. */
216121869Sjeff	short		ksq_nice[SCHED_PRI_NRESV]; /* KSEs in each nice bin. */
217113357Sjeff	short		ksq_nicemin;		/* Least nice. */
218110267Sjeff#ifdef SMP
219121896Sjeff	int		ksq_load_transferable;	/* kses that may be migrated. */
220121923Sjeff	int		ksq_idled;
221117237Sjeff	int		ksq_cpus;	/* Count of CPUs in this kseq. */
222122848Sjeff	volatile struct kse *ksq_assigned;	/* assigned by another CPU. */
223110267Sjeff#endif
224109864Sjeff};
225109864Sjeff
226109864Sjeff/*
227109864Sjeff * One kse queue per processor.
228109864Sjeff */
229110028Sjeff#ifdef SMP
230121790Sjeffstatic int kseq_idle;
231121790Sjeffstatic struct kseq	kseq_cpu[MAXCPU];
232121790Sjeffstatic struct kseq	*kseq_idmap[MAXCPU];
233117237Sjeff#define	KSEQ_SELF()	(kseq_idmap[PCPU_GET(cpuid)])
234117237Sjeff#define	KSEQ_CPU(x)	(kseq_idmap[(x)])
235110028Sjeff#else
236121790Sjeffstatic struct kseq	kseq_cpu;
237110028Sjeff#define	KSEQ_SELF()	(&kseq_cpu)
238110028Sjeff#define	KSEQ_CPU(x)	(&kseq_cpu)
239110028Sjeff#endif
240109864Sjeff
241112966Sjeffstatic void sched_slice(struct kse *ke);
242113357Sjeffstatic void sched_priority(struct ksegrp *kg);
243111857Sjeffstatic int sched_interact_score(struct ksegrp *kg);
244116463Sjeffstatic void sched_interact_update(struct ksegrp *kg);
245121868Sjeffstatic void sched_interact_fork(struct ksegrp *kg);
246121790Sjeffstatic void sched_pctcpu_update(struct kse *ke);
247109864Sjeff
248110267Sjeff/* Operations on per processor queues */
249121790Sjeffstatic struct kse * kseq_choose(struct kseq *kseq);
250110028Sjeffstatic void kseq_setup(struct kseq *kseq);
251122744Sjeffstatic void kseq_load_add(struct kseq *kseq, struct kse *ke);
252122744Sjeffstatic void kseq_load_rem(struct kseq *kseq, struct kse *ke);
253122744Sjeffstatic __inline void kseq_runq_add(struct kseq *kseq, struct kse *ke);
254122744Sjeffstatic __inline void kseq_runq_rem(struct kseq *kseq, struct kse *ke);
255113357Sjeffstatic void kseq_nice_add(struct kseq *kseq, int nice);
256113357Sjeffstatic void kseq_nice_rem(struct kseq *kseq, int nice);
257113660Sjeffvoid kseq_print(int cpu);
258110267Sjeff#ifdef SMP
259121790Sjeffstatic struct kse *runq_steal(struct runq *rq);
260122744Sjeffstatic void sched_balance(void *arg);
261121790Sjeffstatic void kseq_move(struct kseq *from, int cpu);
262121923Sjeffstatic __inline void kseq_setidle(struct kseq *kseq);
263121790Sjeffstatic void kseq_notify(struct kse *ke, int cpu);
264121790Sjeffstatic void kseq_assign(struct kseq *);
265121790Sjeffstatic struct kse *kseq_steal(struct kseq *kseq);
266122038Sjeff#define	KSE_CAN_MIGRATE(ke, class)					\
267122158Sjeff    ((class) != PRI_ITHD && (ke)->ke_thread->td_pinned == 0 &&		\
268122165Sjeff    ((ke)->ke_flags & KEF_BOUND) == 0)
269121790Sjeff#endif
270110028Sjeff
271113357Sjeffvoid
272113660Sjeffkseq_print(int cpu)
273110267Sjeff{
274113660Sjeff	struct kseq *kseq;
275113357Sjeff	int i;
276112994Sjeff
277113660Sjeff	kseq = KSEQ_CPU(cpu);
278112994Sjeff
279113357Sjeff	printf("kseq:\n");
280113357Sjeff	printf("\tload:           %d\n", kseq->ksq_load);
281122744Sjeff	printf("\tload TIMESHARE: %d\n", kseq->ksq_load_timeshare);
282121896Sjeff#ifdef SMP
283121896Sjeff	printf("\tload transferable: %d\n", kseq->ksq_load_transferable);
284121896Sjeff#endif
285113357Sjeff	printf("\tnicemin:\t%d\n", kseq->ksq_nicemin);
286113357Sjeff	printf("\tnice counts:\n");
287121869Sjeff	for (i = 0; i < SCHED_PRI_NRESV; i++)
288113357Sjeff		if (kseq->ksq_nice[i])
289113357Sjeff			printf("\t\t%d = %d\n",
290113357Sjeff			    i - SCHED_PRI_NHALF, kseq->ksq_nice[i]);
291113357Sjeff}
292112994Sjeff
293122744Sjeffstatic __inline void
294122744Sjeffkseq_runq_add(struct kseq *kseq, struct kse *ke)
295122744Sjeff{
296122744Sjeff#ifdef SMP
297122744Sjeff	if (KSE_CAN_MIGRATE(ke, PRI_BASE(ke->ke_ksegrp->kg_pri_class)))
298122744Sjeff		kseq->ksq_load_transferable++;
299122744Sjeff#endif
300122744Sjeff	runq_add(ke->ke_runq, ke);
301122744Sjeff}
302122744Sjeff
303122744Sjeffstatic __inline void
304122744Sjeffkseq_runq_rem(struct kseq *kseq, struct kse *ke)
305122744Sjeff{
306122744Sjeff#ifdef SMP
307122744Sjeff	if (KSE_CAN_MIGRATE(ke, PRI_BASE(ke->ke_ksegrp->kg_pri_class)))
308122744Sjeff		kseq->ksq_load_transferable--;
309122744Sjeff#endif
310122744Sjeff	runq_remove(ke->ke_runq, ke);
311122744Sjeff}
312122744Sjeff
313113357Sjeffstatic void
314122744Sjeffkseq_load_add(struct kseq *kseq, struct kse *ke)
315113357Sjeff{
316121896Sjeff	int class;
317115998Sjeff	mtx_assert(&sched_lock, MA_OWNED);
318121896Sjeff	class = PRI_BASE(ke->ke_ksegrp->kg_pri_class);
319121896Sjeff	if (class == PRI_TIMESHARE)
320121896Sjeff		kseq->ksq_load_timeshare++;
321113357Sjeff	kseq->ksq_load++;
322113357Sjeff	if (ke->ke_ksegrp->kg_pri_class == PRI_TIMESHARE)
323122744Sjeff		CTR6(KTR_ULE,
324122744Sjeff		    "Add kse %p to %p (slice: %d, pri: %d, nice: %d(%d))",
325122744Sjeff		    ke, ke->ke_runq, ke->ke_slice, ke->ke_thread->td_priority,
326122744Sjeff		    ke->ke_ksegrp->kg_nice, kseq->ksq_nicemin);
327113357Sjeff	if (ke->ke_ksegrp->kg_pri_class == PRI_TIMESHARE)
328113357Sjeff		kseq_nice_add(kseq, ke->ke_ksegrp->kg_nice);
329110267Sjeff}
330113357Sjeff
331112994Sjeffstatic void
332122744Sjeffkseq_load_rem(struct kseq *kseq, struct kse *ke)
333110267Sjeff{
334121896Sjeff	int class;
335115998Sjeff	mtx_assert(&sched_lock, MA_OWNED);
336121896Sjeff	class = PRI_BASE(ke->ke_ksegrp->kg_pri_class);
337121896Sjeff	if (class == PRI_TIMESHARE)
338121896Sjeff		kseq->ksq_load_timeshare--;
339113357Sjeff	kseq->ksq_load--;
340113357Sjeff	ke->ke_runq = NULL;
341113357Sjeff	if (ke->ke_ksegrp->kg_pri_class == PRI_TIMESHARE)
342113357Sjeff		kseq_nice_rem(kseq, ke->ke_ksegrp->kg_nice);
343110267Sjeff}
344110267Sjeff
345113357Sjeffstatic void
346113357Sjeffkseq_nice_add(struct kseq *kseq, int nice)
347110267Sjeff{
348115998Sjeff	mtx_assert(&sched_lock, MA_OWNED);
349113357Sjeff	/* Normalize to zero. */
350113357Sjeff	kseq->ksq_nice[nice + SCHED_PRI_NHALF]++;
351121896Sjeff	if (nice < kseq->ksq_nicemin || kseq->ksq_load_timeshare == 1)
352113357Sjeff		kseq->ksq_nicemin = nice;
353110267Sjeff}
354110267Sjeff
355113357Sjeffstatic void
356113357Sjeffkseq_nice_rem(struct kseq *kseq, int nice)
357110267Sjeff{
358113357Sjeff	int n;
359113357Sjeff
360115998Sjeff	mtx_assert(&sched_lock, MA_OWNED);
361113357Sjeff	/* Normalize to zero. */
362113357Sjeff	n = nice + SCHED_PRI_NHALF;
363113357Sjeff	kseq->ksq_nice[n]--;
364113357Sjeff	KASSERT(kseq->ksq_nice[n] >= 0, ("Negative nice count."));
365113357Sjeff
366113357Sjeff	/*
367113357Sjeff	 * If this wasn't the smallest nice value or there are more in
368113357Sjeff	 * this bucket we can just return.  Otherwise we have to recalculate
369113357Sjeff	 * the smallest nice.
370113357Sjeff	 */
371113357Sjeff	if (nice != kseq->ksq_nicemin ||
372113357Sjeff	    kseq->ksq_nice[n] != 0 ||
373121896Sjeff	    kseq->ksq_load_timeshare == 0)
374113357Sjeff		return;
375113357Sjeff
376121869Sjeff	for (; n < SCHED_PRI_NRESV; n++)
377113357Sjeff		if (kseq->ksq_nice[n]) {
378113357Sjeff			kseq->ksq_nicemin = n - SCHED_PRI_NHALF;
379113357Sjeff			return;
380113357Sjeff		}
381110267Sjeff}
382110267Sjeff
383113357Sjeff#ifdef SMP
384116069Sjeff/*
385122744Sjeff * sched_balance is a simple CPU load balancing algorithm.  It operates by
386116069Sjeff * finding the least loaded and most loaded cpu and equalizing their load
387116069Sjeff * by migrating some processes.
388116069Sjeff *
389116069Sjeff * Dealing only with two CPUs at a time has two advantages.  Firstly, most
390116069Sjeff * installations will only have 2 cpus.  Secondly, load balancing too much at
391116069Sjeff * once can have an unpleasant effect on the system.  The scheduler rarely has
392116069Sjeff * enough information to make perfect decisions.  So this algorithm chooses
393116069Sjeff * algorithm simplicity and more gradual effects on load in larger systems.
394116069Sjeff *
395116069Sjeff * It could be improved by considering the priorities and slices assigned to
396116069Sjeff * each task prior to balancing them.  There are many pathological cases with
397116069Sjeff * any approach and so the semi random algorithm below may work as well as any.
398116069Sjeff *
399116069Sjeff */
400121790Sjeffstatic void
401122744Sjeffsched_balance(void *arg)
402116069Sjeff{
403116069Sjeff	struct kseq *kseq;
404116069Sjeff	int high_load;
405116069Sjeff	int low_load;
406116069Sjeff	int high_cpu;
407116069Sjeff	int low_cpu;
408116069Sjeff	int move;
409116069Sjeff	int diff;
410116069Sjeff	int i;
411116069Sjeff
412116069Sjeff	high_cpu = 0;
413116069Sjeff	low_cpu = 0;
414116069Sjeff	high_load = 0;
415116069Sjeff	low_load = -1;
416116069Sjeff
417116069Sjeff	mtx_lock_spin(&sched_lock);
418116962Sjeff	if (smp_started == 0)
419116962Sjeff		goto out;
420116962Sjeff
421123126Sjhb	for (i = 0; i <= mp_maxid; i++) {
422116970Sjeff		if (CPU_ABSENT(i) || (i & stopped_cpus) != 0)
423116069Sjeff			continue;
424116069Sjeff		kseq = KSEQ_CPU(i);
425122744Sjeff		if (kseq->ksq_load_transferable > high_load) {
426122744Sjeff			high_load = kseq->ksq_load_transferable;
427116069Sjeff			high_cpu = i;
428116069Sjeff		}
429116069Sjeff		if (low_load == -1 || kseq->ksq_load < low_load) {
430116069Sjeff			low_load = kseq->ksq_load;
431116069Sjeff			low_cpu = i;
432116069Sjeff		}
433116069Sjeff	}
434117237Sjeff	kseq = KSEQ_CPU(high_cpu);
435116069Sjeff	/*
436116069Sjeff	 * Nothing to do.
437116069Sjeff	 */
438122744Sjeff	if (high_load == 0 || low_load >= kseq->ksq_load)
439116069Sjeff		goto out;
440122744Sjeff	/*
441122744Sjeff	 * Determine what the imbalance is and then adjust that to how many
442122744Sjeff	 * kses we actually have to give up (load_transferable).
443122744Sjeff	 */
444122744Sjeff	diff = kseq->ksq_load - low_load;
445116069Sjeff	move = diff / 2;
446116069Sjeff	if (diff & 0x1)
447116069Sjeff		move++;
448122744Sjeff	move = min(move, high_load);
449116069Sjeff	for (i = 0; i < move; i++)
450117237Sjeff		kseq_move(kseq, low_cpu);
451116069Sjeffout:
452116069Sjeff	mtx_unlock_spin(&sched_lock);
453122744Sjeff	callout_reset(&kseq_lb_callout, hz, sched_balance, NULL);
454116069Sjeff
455116069Sjeff	return;
456116069Sjeff}
457116069Sjeff
458121790Sjeffstatic void
459116069Sjeffkseq_move(struct kseq *from, int cpu)
460116069Sjeff{
461116069Sjeff	struct kse *ke;
462116069Sjeff
463121790Sjeff	ke = kseq_steal(from);
464116069Sjeff	ke->ke_state = KES_THREAD;
465122744Sjeff	kseq_runq_rem(from, ke);
466122744Sjeff	kseq_load_rem(from, ke);
467116069Sjeff
468116069Sjeff	ke->ke_cpu = cpu;
469121923Sjeff	kseq_notify(ke, cpu);
470116069Sjeff}
471110267Sjeff
472121923Sjeffstatic __inline void
473121923Sjeffkseq_setidle(struct kseq *kseq)
474121790Sjeff{
475121923Sjeff	if (kseq->ksq_idled)
476121923Sjeff		return;
477121923Sjeff	kseq->ksq_idled = 1;
478121923Sjeff	atomic_set_int(&kseq_idle, PCPU_GET(cpumask));
479121923Sjeff	return;
480121790Sjeff}
481121790Sjeff
482121790Sjeffstatic void
483121790Sjeffkseq_assign(struct kseq *kseq)
484121790Sjeff{
485121790Sjeff	struct kse *nke;
486121790Sjeff	struct kse *ke;
487121790Sjeff
488121790Sjeff	do {
489122848Sjeff		(volatile struct kse *)ke = kseq->ksq_assigned;
490121790Sjeff	} while(!atomic_cmpset_ptr(&kseq->ksq_assigned, ke, NULL));
491121790Sjeff	for (; ke != NULL; ke = nke) {
492121790Sjeff		nke = ke->ke_assign;
493121790Sjeff		ke->ke_flags &= ~KEF_ASSIGNED;
494121790Sjeff		sched_add(ke->ke_thread);
495121790Sjeff	}
496121790Sjeff}
497121790Sjeff
498121790Sjeffstatic void
499121790Sjeffkseq_notify(struct kse *ke, int cpu)
500121790Sjeff{
501121790Sjeff	struct kseq *kseq;
502121790Sjeff	struct thread *td;
503121790Sjeff	struct pcpu *pcpu;
504121790Sjeff
505121790Sjeff	ke->ke_flags |= KEF_ASSIGNED;
506121790Sjeff
507121790Sjeff	kseq = KSEQ_CPU(cpu);
508121790Sjeff
509121790Sjeff	/*
510121790Sjeff	 * Place a KSE on another cpu's queue and force a resched.
511121790Sjeff	 */
512121790Sjeff	do {
513122848Sjeff		(volatile struct kse *)ke->ke_assign = kseq->ksq_assigned;
514121790Sjeff	} while(!atomic_cmpset_ptr(&kseq->ksq_assigned, ke->ke_assign, ke));
515121790Sjeff	pcpu = pcpu_find(cpu);
516121790Sjeff	td = pcpu->pc_curthread;
517121790Sjeff	if (ke->ke_thread->td_priority < td->td_priority ||
518121790Sjeff	    td == pcpu->pc_idlethread) {
519121790Sjeff		td->td_flags |= TDF_NEEDRESCHED;
520121790Sjeff		ipi_selected(1 << cpu, IPI_AST);
521121790Sjeff	}
522121790Sjeff}
523121790Sjeff
524121790Sjeffstatic struct kse *
525121790Sjeffrunq_steal(struct runq *rq)
526121790Sjeff{
527121790Sjeff	struct rqhead *rqh;
528121790Sjeff	struct rqbits *rqb;
529121790Sjeff	struct kse *ke;
530121790Sjeff	int word;
531121790Sjeff	int bit;
532121790Sjeff
533121790Sjeff	mtx_assert(&sched_lock, MA_OWNED);
534121790Sjeff	rqb = &rq->rq_status;
535121790Sjeff	for (word = 0; word < RQB_LEN; word++) {
536121790Sjeff		if (rqb->rqb_bits[word] == 0)
537121790Sjeff			continue;
538121790Sjeff		for (bit = 0; bit < RQB_BPW; bit++) {
539123231Speter			if ((rqb->rqb_bits[word] & (1ul << bit)) == 0)
540121790Sjeff				continue;
541121790Sjeff			rqh = &rq->rq_queues[bit + (word << RQB_L2BPW)];
542121790Sjeff			TAILQ_FOREACH(ke, rqh, ke_procq) {
543121896Sjeff				if (KSE_CAN_MIGRATE(ke,
544121896Sjeff				    PRI_BASE(ke->ke_ksegrp->kg_pri_class)))
545121790Sjeff					return (ke);
546121790Sjeff			}
547121790Sjeff		}
548121790Sjeff	}
549121790Sjeff	return (NULL);
550121790Sjeff}
551121790Sjeff
552121790Sjeffstatic struct kse *
553121790Sjeffkseq_steal(struct kseq *kseq)
554121790Sjeff{
555121790Sjeff	struct kse *ke;
556121790Sjeff
557121790Sjeff	if ((ke = runq_steal(kseq->ksq_curr)) != NULL)
558121790Sjeff		return (ke);
559121790Sjeff	if ((ke = runq_steal(kseq->ksq_next)) != NULL)
560121790Sjeff		return (ke);
561121790Sjeff	return (runq_steal(&kseq->ksq_idle));
562121790Sjeff}
563121790Sjeff#endif	/* SMP */
564121790Sjeff
565117326Sjeff/*
566121790Sjeff * Pick the highest priority task we have and return it.
567117326Sjeff */
568117326Sjeff
569121790Sjeffstatic struct kse *
570121790Sjeffkseq_choose(struct kseq *kseq)
571110267Sjeff{
572110267Sjeff	struct kse *ke;
573110267Sjeff	struct runq *swap;
574110267Sjeff
575115998Sjeff	mtx_assert(&sched_lock, MA_OWNED);
576113357Sjeff	swap = NULL;
577112994Sjeff
578113357Sjeff	for (;;) {
579113357Sjeff		ke = runq_choose(kseq->ksq_curr);
580113357Sjeff		if (ke == NULL) {
581113357Sjeff			/*
582113357Sjeff			 * We already swaped once and didn't get anywhere.
583113357Sjeff			 */
584113357Sjeff			if (swap)
585113357Sjeff				break;
586113357Sjeff			swap = kseq->ksq_curr;
587113357Sjeff			kseq->ksq_curr = kseq->ksq_next;
588113357Sjeff			kseq->ksq_next = swap;
589113357Sjeff			continue;
590113357Sjeff		}
591113357Sjeff		/*
592113357Sjeff		 * If we encounter a slice of 0 the kse is in a
593113357Sjeff		 * TIMESHARE kse group and its nice was too far out
594113357Sjeff		 * of the range that receives slices.
595113357Sjeff		 */
596121790Sjeff		if (ke->ke_slice == 0) {
597113357Sjeff			runq_remove(ke->ke_runq, ke);
598113357Sjeff			sched_slice(ke);
599113357Sjeff			ke->ke_runq = kseq->ksq_next;
600113357Sjeff			runq_add(ke->ke_runq, ke);
601113357Sjeff			continue;
602113357Sjeff		}
603113357Sjeff		return (ke);
604110267Sjeff	}
605110267Sjeff
606113357Sjeff	return (runq_choose(&kseq->ksq_idle));
607110267Sjeff}
608110267Sjeff
609109864Sjeffstatic void
610110028Sjeffkseq_setup(struct kseq *kseq)
611110028Sjeff{
612113357Sjeff	runq_init(&kseq->ksq_timeshare[0]);
613113357Sjeff	runq_init(&kseq->ksq_timeshare[1]);
614112994Sjeff	runq_init(&kseq->ksq_idle);
615113357Sjeff	kseq->ksq_curr = &kseq->ksq_timeshare[0];
616113357Sjeff	kseq->ksq_next = &kseq->ksq_timeshare[1];
617113660Sjeff	kseq->ksq_load = 0;
618121896Sjeff	kseq->ksq_load_timeshare = 0;
619110267Sjeff#ifdef SMP
620121896Sjeff	kseq->ksq_load_transferable = 0;
621121923Sjeff	kseq->ksq_idled = 0;
622121790Sjeff	kseq->ksq_assigned = NULL;
623110267Sjeff#endif
624110028Sjeff}
625110028Sjeff
626110028Sjeffstatic void
627109864Sjeffsched_setup(void *dummy)
628109864Sjeff{
629117313Sjeff#ifdef SMP
630109864Sjeff	int i;
631117313Sjeff#endif
632109864Sjeff
633116946Sjeff	slice_min = (hz/100);	/* 10ms */
634116946Sjeff	slice_max = (hz/7);	/* ~140ms */
635111857Sjeff
636117237Sjeff#ifdef SMP
637109864Sjeff	/* init kseqs */
638117237Sjeff	/* Create the idmap. */
639117237Sjeff#ifdef ULE_HTT_EXPERIMENTAL
640117237Sjeff	if (smp_topology == NULL) {
641117237Sjeff#else
642117237Sjeff	if (1) {
643117237Sjeff#endif
644117237Sjeff		for (i = 0; i < MAXCPU; i++) {
645117237Sjeff			kseq_setup(&kseq_cpu[i]);
646117237Sjeff			kseq_idmap[i] = &kseq_cpu[i];
647117237Sjeff			kseq_cpu[i].ksq_cpus = 1;
648117237Sjeff		}
649117237Sjeff	} else {
650117237Sjeff		int j;
651113357Sjeff
652117237Sjeff		for (i = 0; i < smp_topology->ct_count; i++) {
653117237Sjeff			struct cpu_group *cg;
654117237Sjeff
655117237Sjeff			cg = &smp_topology->ct_group[i];
656117237Sjeff			kseq_setup(&kseq_cpu[i]);
657117237Sjeff
658117237Sjeff			for (j = 0; j < MAXCPU; j++)
659117237Sjeff				if ((cg->cg_mask & (1 << j)) != 0)
660117237Sjeff					kseq_idmap[j] = &kseq_cpu[i];
661117237Sjeff			kseq_cpu[i].ksq_cpus = cg->cg_count;
662117237Sjeff		}
663117237Sjeff	}
664119137Ssam	callout_init(&kseq_lb_callout, CALLOUT_MPSAFE);
665122744Sjeff	sched_balance(NULL);
666117237Sjeff#else
667117237Sjeff	kseq_setup(KSEQ_SELF());
668116069Sjeff#endif
669117237Sjeff	mtx_lock_spin(&sched_lock);
670122744Sjeff	kseq_load_add(KSEQ_SELF(), &kse0);
671117237Sjeff	mtx_unlock_spin(&sched_lock);
672109864Sjeff}
673109864Sjeff
674109864Sjeff/*
675109864Sjeff * Scale the scheduling priority according to the "interactivity" of this
676109864Sjeff * process.
677109864Sjeff */
678113357Sjeffstatic void
679109864Sjeffsched_priority(struct ksegrp *kg)
680109864Sjeff{
681109864Sjeff	int pri;
682109864Sjeff
683109864Sjeff	if (kg->kg_pri_class != PRI_TIMESHARE)
684113357Sjeff		return;
685109864Sjeff
686113357Sjeff	pri = SCHED_PRI_INTERACT(sched_interact_score(kg));
687111857Sjeff	pri += SCHED_PRI_BASE;
688109864Sjeff	pri += kg->kg_nice;
689109864Sjeff
690109864Sjeff	if (pri > PRI_MAX_TIMESHARE)
691109864Sjeff		pri = PRI_MAX_TIMESHARE;
692109864Sjeff	else if (pri < PRI_MIN_TIMESHARE)
693109864Sjeff		pri = PRI_MIN_TIMESHARE;
694109864Sjeff
695109864Sjeff	kg->kg_user_pri = pri;
696109864Sjeff
697113357Sjeff	return;
698109864Sjeff}
699109864Sjeff
700109864Sjeff/*
701112966Sjeff * Calculate a time slice based on the properties of the kseg and the runq
702112994Sjeff * that we're on.  This is only for PRI_TIMESHARE ksegrps.
703109864Sjeff */
704112966Sjeffstatic void
705112966Sjeffsched_slice(struct kse *ke)
706109864Sjeff{
707113357Sjeff	struct kseq *kseq;
708112966Sjeff	struct ksegrp *kg;
709109864Sjeff
710112966Sjeff	kg = ke->ke_ksegrp;
711113357Sjeff	kseq = KSEQ_CPU(ke->ke_cpu);
712109864Sjeff
713112966Sjeff	/*
714112966Sjeff	 * Rationale:
715112966Sjeff	 * KSEs in interactive ksegs get the minimum slice so that we
716112966Sjeff	 * quickly notice if it abuses its advantage.
717112966Sjeff	 *
718112966Sjeff	 * KSEs in non-interactive ksegs are assigned a slice that is
719112966Sjeff	 * based on the ksegs nice value relative to the least nice kseg
720112966Sjeff	 * on the run queue for this cpu.
721112966Sjeff	 *
722112966Sjeff	 * If the KSE is less nice than all others it gets the maximum
723112966Sjeff	 * slice and other KSEs will adjust their slice relative to
724112966Sjeff	 * this when they first expire.
725112966Sjeff	 *
726112966Sjeff	 * There is 20 point window that starts relative to the least
727112966Sjeff	 * nice kse on the run queue.  Slice size is determined by
728112966Sjeff	 * the kse distance from the last nice ksegrp.
729112966Sjeff	 *
730121871Sjeff	 * If the kse is outside of the window it will get no slice
731121871Sjeff	 * and will be reevaluated each time it is selected on the
732121871Sjeff	 * run queue.  The exception to this is nice 0 ksegs when
733121871Sjeff	 * a nice -20 is running.  They are always granted a minimum
734121871Sjeff	 * slice.
735112966Sjeff	 */
736113357Sjeff	if (!SCHED_INTERACTIVE(kg)) {
737112966Sjeff		int nice;
738112966Sjeff
739113357Sjeff		nice = kg->kg_nice + (0 - kseq->ksq_nicemin);
740121896Sjeff		if (kseq->ksq_load_timeshare == 0 ||
741113357Sjeff		    kg->kg_nice < kseq->ksq_nicemin)
742112966Sjeff			ke->ke_slice = SCHED_SLICE_MAX;
743121871Sjeff		else if (nice <= SCHED_SLICE_NTHRESH)
744112966Sjeff			ke->ke_slice = SCHED_SLICE_NICE(nice);
745121871Sjeff		else if (kg->kg_nice == 0)
746121871Sjeff			ke->ke_slice = SCHED_SLICE_MIN;
747112966Sjeff		else
748112966Sjeff			ke->ke_slice = 0;
749112966Sjeff	} else
750112966Sjeff		ke->ke_slice = SCHED_SLICE_MIN;
751112966Sjeff
752113357Sjeff	CTR6(KTR_ULE,
753113357Sjeff	    "Sliced %p(%d) (nice: %d, nicemin: %d, load: %d, interactive: %d)",
754113357Sjeff	    ke, ke->ke_slice, kg->kg_nice, kseq->ksq_nicemin,
755121896Sjeff	    kseq->ksq_load_timeshare, SCHED_INTERACTIVE(kg));
756113357Sjeff
757112966Sjeff	return;
758109864Sjeff}
759109864Sjeff
760121868Sjeff/*
761121868Sjeff * This routine enforces a maximum limit on the amount of scheduling history
762121868Sjeff * kept.  It is called after either the slptime or runtime is adjusted.
763121868Sjeff * This routine will not operate correctly when slp or run times have been
764121868Sjeff * adjusted to more than double their maximum.
765121868Sjeff */
766116463Sjeffstatic void
767116463Sjeffsched_interact_update(struct ksegrp *kg)
768116463Sjeff{
769121868Sjeff	int sum;
770121605Sjeff
771121868Sjeff	sum = kg->kg_runtime + kg->kg_slptime;
772121868Sjeff	if (sum < SCHED_SLP_RUN_MAX)
773121868Sjeff		return;
774121868Sjeff	/*
775121868Sjeff	 * If we have exceeded by more than 1/5th then the algorithm below
776121868Sjeff	 * will not bring us back into range.  Dividing by two here forces
777121868Sjeff	 * us into the range of [3/5 * SCHED_INTERACT_MAX, SCHED_INTERACT_MAX]
778121868Sjeff	 */
779121868Sjeff	if (sum > (SCHED_INTERACT_MAX / 5) * 6) {
780121868Sjeff		kg->kg_runtime /= 2;
781121868Sjeff		kg->kg_slptime /= 2;
782121868Sjeff		return;
783116463Sjeff	}
784121868Sjeff	kg->kg_runtime = (kg->kg_runtime / 5) * 4;
785121868Sjeff	kg->kg_slptime = (kg->kg_slptime / 5) * 4;
786116463Sjeff}
787116463Sjeff
788121868Sjeffstatic void
789121868Sjeffsched_interact_fork(struct ksegrp *kg)
790121868Sjeff{
791121868Sjeff	int ratio;
792121868Sjeff	int sum;
793121868Sjeff
794121868Sjeff	sum = kg->kg_runtime + kg->kg_slptime;
795121868Sjeff	if (sum > SCHED_SLP_RUN_FORK) {
796121868Sjeff		ratio = sum / SCHED_SLP_RUN_FORK;
797121868Sjeff		kg->kg_runtime /= ratio;
798121868Sjeff		kg->kg_slptime /= ratio;
799121868Sjeff	}
800121868Sjeff}
801121868Sjeff
802111857Sjeffstatic int
803111857Sjeffsched_interact_score(struct ksegrp *kg)
804111857Sjeff{
805116365Sjeff	int div;
806111857Sjeff
807111857Sjeff	if (kg->kg_runtime > kg->kg_slptime) {
808116365Sjeff		div = max(1, kg->kg_runtime / SCHED_INTERACT_HALF);
809116365Sjeff		return (SCHED_INTERACT_HALF +
810116365Sjeff		    (SCHED_INTERACT_HALF - (kg->kg_slptime / div)));
811116365Sjeff	} if (kg->kg_slptime > kg->kg_runtime) {
812116365Sjeff		div = max(1, kg->kg_slptime / SCHED_INTERACT_HALF);
813116365Sjeff		return (kg->kg_runtime / div);
814111857Sjeff	}
815111857Sjeff
816116365Sjeff	/*
817116365Sjeff	 * This can happen if slptime and runtime are 0.
818116365Sjeff	 */
819116365Sjeff	return (0);
820111857Sjeff
821111857Sjeff}
822111857Sjeff
823113357Sjeff/*
824113357Sjeff * This is only somewhat accurate since given many processes of the same
825113357Sjeff * priority they will switch when their slices run out, which will be
826113357Sjeff * at most SCHED_SLICE_MAX.
827113357Sjeff */
828109864Sjeffint
829109864Sjeffsched_rr_interval(void)
830109864Sjeff{
831109864Sjeff	return (SCHED_SLICE_MAX);
832109864Sjeff}
833109864Sjeff
834121790Sjeffstatic void
835109864Sjeffsched_pctcpu_update(struct kse *ke)
836109864Sjeff{
837109864Sjeff	/*
838109864Sjeff	 * Adjust counters and watermark for pctcpu calc.
839116365Sjeff	 */
840120272Sjeff	if (ke->ke_ltick > ticks - SCHED_CPU_TICKS) {
841120272Sjeff		/*
842120272Sjeff		 * Shift the tick count out so that the divide doesn't
843120272Sjeff		 * round away our results.
844120272Sjeff		 */
845120272Sjeff		ke->ke_ticks <<= 10;
846120272Sjeff		ke->ke_ticks = (ke->ke_ticks / (ticks - ke->ke_ftick)) *
847120272Sjeff			    SCHED_CPU_TICKS;
848120272Sjeff		ke->ke_ticks >>= 10;
849120272Sjeff	} else
850120272Sjeff		ke->ke_ticks = 0;
851109864Sjeff	ke->ke_ltick = ticks;
852109864Sjeff	ke->ke_ftick = ke->ke_ltick - SCHED_CPU_TICKS;
853109864Sjeff}
854109864Sjeff
855109864Sjeffvoid
856109864Sjeffsched_prio(struct thread *td, u_char prio)
857109864Sjeff{
858121605Sjeff	struct kse *ke;
859109864Sjeff
860121605Sjeff	ke = td->td_kse;
861109864Sjeff	mtx_assert(&sched_lock, MA_OWNED);
862109864Sjeff	if (TD_ON_RUNQ(td)) {
863121605Sjeff		/*
864121605Sjeff		 * If the priority has been elevated due to priority
865121605Sjeff		 * propagation, we may have to move ourselves to a new
866121605Sjeff		 * queue.  We still call adjustrunqueue below in case kse
867121605Sjeff		 * needs to fix things up.
868121605Sjeff		 */
869121872Sjeff		if (prio < td->td_priority && ke &&
870121872Sjeff		    (ke->ke_flags & KEF_ASSIGNED) == 0 &&
871121790Sjeff		    ke->ke_runq != KSEQ_CPU(ke->ke_cpu)->ksq_curr) {
872121605Sjeff			runq_remove(ke->ke_runq, ke);
873121605Sjeff			ke->ke_runq = KSEQ_CPU(ke->ke_cpu)->ksq_curr;
874121605Sjeff			runq_add(ke->ke_runq, ke);
875121605Sjeff		}
876119488Sdavidxu		adjustrunqueue(td, prio);
877121605Sjeff	} else
878119488Sdavidxu		td->td_priority = prio;
879109864Sjeff}
880109864Sjeff
881109864Sjeffvoid
882121128Sjeffsched_switch(struct thread *td)
883109864Sjeff{
884121128Sjeff	struct thread *newtd;
885109864Sjeff	struct kse *ke;
886109864Sjeff
887109864Sjeff	mtx_assert(&sched_lock, MA_OWNED);
888109864Sjeff
889109864Sjeff	ke = td->td_kse;
890109864Sjeff
891109864Sjeff	td->td_last_kse = ke;
892113339Sjulian        td->td_lastcpu = td->td_oncpu;
893113339Sjulian	td->td_oncpu = NOCPU;
894111032Sjulian        td->td_flags &= ~TDF_NEEDRESCHED;
895109864Sjeff
896109864Sjeff	if (TD_IS_RUNNING(td)) {
897119488Sdavidxu		if (td->td_proc->p_flag & P_SA) {
898122744Sjeff			kseq_load_rem(KSEQ_CPU(ke->ke_cpu), ke);
899119488Sdavidxu			setrunqueue(td);
900119488Sdavidxu		} else {
901119488Sdavidxu			/*
902121605Sjeff			 * This queue is always correct except for idle threads
903121605Sjeff			 * which have a higher priority due to priority
904121605Sjeff			 * propagation.
905119488Sdavidxu			 */
906121605Sjeff			if (ke->ke_ksegrp->kg_pri_class == PRI_IDLE) {
907121605Sjeff				if (td->td_priority < PRI_MIN_IDLE)
908121605Sjeff					ke->ke_runq = KSEQ_SELF()->ksq_curr;
909121605Sjeff				else
910121605Sjeff					ke->ke_runq = &KSEQ_SELF()->ksq_idle;
911121605Sjeff			}
912122744Sjeff			kseq_runq_add(KSEQ_SELF(), ke);
913119488Sdavidxu		}
914121146Sjeff	} else {
915121146Sjeff		if (ke->ke_runq)
916122744Sjeff			kseq_load_rem(KSEQ_CPU(ke->ke_cpu), ke);
917121146Sjeff		/*
918121146Sjeff		 * We will not be on the run queue. So we must be
919121146Sjeff		 * sleeping or similar.
920121146Sjeff		 */
921121146Sjeff		if (td->td_proc->p_flag & P_SA)
922121146Sjeff			kse_reassign(ke);
923121146Sjeff	}
924121128Sjeff	newtd = choosethread();
925121128Sjeff	if (td != newtd)
926121128Sjeff		cpu_switch(td, newtd);
927121128Sjeff	sched_lock.mtx_lock = (uintptr_t)td;
928109864Sjeff
929113339Sjulian	td->td_oncpu = PCPU_GET(cpuid);
930109864Sjeff}
931109864Sjeff
932109864Sjeffvoid
933109864Sjeffsched_nice(struct ksegrp *kg, int nice)
934109864Sjeff{
935113357Sjeff	struct kse *ke;
936109864Sjeff	struct thread *td;
937113357Sjeff	struct kseq *kseq;
938109864Sjeff
939113873Sjhb	PROC_LOCK_ASSERT(kg->kg_proc, MA_OWNED);
940113873Sjhb	mtx_assert(&sched_lock, MA_OWNED);
941113357Sjeff	/*
942113357Sjeff	 * We need to adjust the nice counts for running KSEs.
943113357Sjeff	 */
944113357Sjeff	if (kg->kg_pri_class == PRI_TIMESHARE)
945113357Sjeff		FOREACH_KSE_IN_GROUP(kg, ke) {
946116500Sjeff			if (ke->ke_runq == NULL)
947113357Sjeff				continue;
948113357Sjeff			kseq = KSEQ_CPU(ke->ke_cpu);
949113357Sjeff			kseq_nice_rem(kseq, kg->kg_nice);
950113357Sjeff			kseq_nice_add(kseq, nice);
951113357Sjeff		}
952109864Sjeff	kg->kg_nice = nice;
953109864Sjeff	sched_priority(kg);
954113357Sjeff	FOREACH_THREAD_IN_GROUP(kg, td)
955111032Sjulian		td->td_flags |= TDF_NEEDRESCHED;
956109864Sjeff}
957109864Sjeff
958109864Sjeffvoid
959109864Sjeffsched_sleep(struct thread *td, u_char prio)
960109864Sjeff{
961109864Sjeff	mtx_assert(&sched_lock, MA_OWNED);
962109864Sjeff
963109864Sjeff	td->td_slptime = ticks;
964109864Sjeff	td->td_priority = prio;
965109864Sjeff
966113357Sjeff	CTR2(KTR_ULE, "sleep kse %p (tick: %d)",
967113357Sjeff	    td->td_kse, td->td_slptime);
968109864Sjeff}
969109864Sjeff
970109864Sjeffvoid
971109864Sjeffsched_wakeup(struct thread *td)
972109864Sjeff{
973109864Sjeff	mtx_assert(&sched_lock, MA_OWNED);
974109864Sjeff
975109864Sjeff	/*
976109864Sjeff	 * Let the kseg know how long we slept for.  This is because process
977109864Sjeff	 * interactivity behavior is modeled in the kseg.
978109864Sjeff	 */
979111788Sjeff	if (td->td_slptime) {
980111788Sjeff		struct ksegrp *kg;
981113357Sjeff		int hzticks;
982109864Sjeff
983111788Sjeff		kg = td->td_ksegrp;
984121868Sjeff		hzticks = (ticks - td->td_slptime) << 10;
985121868Sjeff		if (hzticks >= SCHED_SLP_RUN_MAX) {
986121868Sjeff			kg->kg_slptime = SCHED_SLP_RUN_MAX;
987121868Sjeff			kg->kg_runtime = 1;
988121868Sjeff		} else {
989121868Sjeff			kg->kg_slptime += hzticks;
990121868Sjeff			sched_interact_update(kg);
991121868Sjeff		}
992111788Sjeff		sched_priority(kg);
993116463Sjeff		if (td->td_kse)
994116463Sjeff			sched_slice(td->td_kse);
995113357Sjeff		CTR2(KTR_ULE, "wakeup kse %p (%d ticks)",
996113357Sjeff		    td->td_kse, hzticks);
997111788Sjeff		td->td_slptime = 0;
998109864Sjeff	}
999109864Sjeff	setrunqueue(td);
1000109864Sjeff}
1001109864Sjeff
1002109864Sjeff/*
1003109864Sjeff * Penalize the parent for creating a new child and initialize the child's
1004109864Sjeff * priority.
1005109864Sjeff */
1006109864Sjeffvoid
1007113357Sjeffsched_fork(struct proc *p, struct proc *p1)
1008109864Sjeff{
1009109864Sjeff
1010109864Sjeff	mtx_assert(&sched_lock, MA_OWNED);
1011109864Sjeff
1012113357Sjeff	sched_fork_ksegrp(FIRST_KSEGRP_IN_PROC(p), FIRST_KSEGRP_IN_PROC(p1));
1013113357Sjeff	sched_fork_kse(FIRST_KSE_IN_PROC(p), FIRST_KSE_IN_PROC(p1));
1014113357Sjeff	sched_fork_thread(FIRST_THREAD_IN_PROC(p), FIRST_THREAD_IN_PROC(p1));
1015113357Sjeff}
1016113357Sjeff
1017113357Sjeffvoid
1018113357Sjeffsched_fork_kse(struct kse *ke, struct kse *child)
1019113357Sjeff{
1020113923Sjhb
1021116365Sjeff	child->ke_slice = 1;	/* Attempt to quickly learn interactivity. */
1022122847Sjeff	child->ke_cpu = ke->ke_cpu;
1023113357Sjeff	child->ke_runq = NULL;
1024113357Sjeff
1025121051Sjeff	/* Grab our parents cpu estimation information. */
1026121051Sjeff	child->ke_ticks = ke->ke_ticks;
1027121051Sjeff	child->ke_ltick = ke->ke_ltick;
1028121051Sjeff	child->ke_ftick = ke->ke_ftick;
1029113357Sjeff}
1030113357Sjeff
1031113357Sjeffvoid
1032113357Sjeffsched_fork_ksegrp(struct ksegrp *kg, struct ksegrp *child)
1033113357Sjeff{
1034113923Sjhb	PROC_LOCK_ASSERT(child->kg_proc, MA_OWNED);
1035116365Sjeff
1036121868Sjeff	child->kg_slptime = kg->kg_slptime;
1037121868Sjeff	child->kg_runtime = kg->kg_runtime;
1038121868Sjeff	child->kg_user_pri = kg->kg_user_pri;
1039121868Sjeff	child->kg_nice = kg->kg_nice;
1040121868Sjeff	sched_interact_fork(child);
1041116463Sjeff	kg->kg_runtime += tickincr << 10;
1042116463Sjeff	sched_interact_update(kg);
1043113357Sjeff
1044121868Sjeff	CTR6(KTR_ULE, "sched_fork_ksegrp: %d(%d, %d) - %d(%d, %d)",
1045121868Sjeff	    kg->kg_proc->p_pid, kg->kg_slptime, kg->kg_runtime,
1046121868Sjeff	    child->kg_proc->p_pid, child->kg_slptime, child->kg_runtime);
1047113357Sjeff}
1048109864Sjeff
1049113357Sjeffvoid
1050113357Sjeffsched_fork_thread(struct thread *td, struct thread *child)
1051113357Sjeff{
1052113357Sjeff}
1053113357Sjeff
1054113357Sjeffvoid
1055113357Sjeffsched_class(struct ksegrp *kg, int class)
1056113357Sjeff{
1057113357Sjeff	struct kseq *kseq;
1058113357Sjeff	struct kse *ke;
1059121896Sjeff	int nclass;
1060121896Sjeff	int oclass;
1061113357Sjeff
1062113923Sjhb	mtx_assert(&sched_lock, MA_OWNED);
1063113357Sjeff	if (kg->kg_pri_class == class)
1064113357Sjeff		return;
1065113357Sjeff
1066121896Sjeff	nclass = PRI_BASE(class);
1067121896Sjeff	oclass = PRI_BASE(kg->kg_pri_class);
1068113357Sjeff	FOREACH_KSE_IN_GROUP(kg, ke) {
1069113357Sjeff		if (ke->ke_state != KES_ONRUNQ &&
1070113357Sjeff		    ke->ke_state != KES_THREAD)
1071113357Sjeff			continue;
1072113357Sjeff		kseq = KSEQ_CPU(ke->ke_cpu);
1073113357Sjeff
1074121896Sjeff#ifdef SMP
1075122744Sjeff		/*
1076122744Sjeff		 * On SMP if we're on the RUNQ we must adjust the transferable
1077122744Sjeff		 * count because could be changing to or from an interrupt
1078122744Sjeff		 * class.
1079122744Sjeff		 */
1080122744Sjeff		if (ke->ke_state == KES_ONRUNQ) {
1081122744Sjeff			if (KSE_CAN_MIGRATE(ke, oclass))
1082122744Sjeff				kseq->ksq_load_transferable--;
1083122744Sjeff			if (KSE_CAN_MIGRATE(ke, nclass))
1084122744Sjeff				kseq->ksq_load_transferable++;
1085122744Sjeff		}
1086121896Sjeff#endif
1087122744Sjeff		if (oclass == PRI_TIMESHARE) {
1088121896Sjeff			kseq->ksq_load_timeshare--;
1089122744Sjeff			kseq_nice_rem(kseq, kg->kg_nice);
1090122744Sjeff		}
1091122744Sjeff		if (nclass == PRI_TIMESHARE) {
1092121896Sjeff			kseq->ksq_load_timeshare++;
1093113357Sjeff			kseq_nice_add(kseq, kg->kg_nice);
1094122744Sjeff		}
1095109970Sjeff	}
1096109970Sjeff
1097113357Sjeff	kg->kg_pri_class = class;
1098109864Sjeff}
1099109864Sjeff
1100109864Sjeff/*
1101109864Sjeff * Return some of the child's priority and interactivity to the parent.
1102109864Sjeff */
1103109864Sjeffvoid
1104113357Sjeffsched_exit(struct proc *p, struct proc *child)
1105109864Sjeff{
1106109864Sjeff	mtx_assert(&sched_lock, MA_OWNED);
1107113372Sjeff	sched_exit_kse(FIRST_KSE_IN_PROC(p), FIRST_KSE_IN_PROC(child));
1108116365Sjeff	sched_exit_ksegrp(FIRST_KSEGRP_IN_PROC(p), FIRST_KSEGRP_IN_PROC(child));
1109109864Sjeff}
1110109864Sjeff
1111109864Sjeffvoid
1112113372Sjeffsched_exit_kse(struct kse *ke, struct kse *child)
1113113372Sjeff{
1114122744Sjeff	kseq_load_rem(KSEQ_CPU(child->ke_cpu), child);
1115113372Sjeff}
1116113372Sjeff
1117113372Sjeffvoid
1118113372Sjeffsched_exit_ksegrp(struct ksegrp *kg, struct ksegrp *child)
1119113372Sjeff{
1120116463Sjeff	/* kg->kg_slptime += child->kg_slptime; */
1121116365Sjeff	kg->kg_runtime += child->kg_runtime;
1122116463Sjeff	sched_interact_update(kg);
1123113372Sjeff}
1124113372Sjeff
1125113372Sjeffvoid
1126113372Sjeffsched_exit_thread(struct thread *td, struct thread *child)
1127113372Sjeff{
1128113372Sjeff}
1129113372Sjeff
1130113372Sjeffvoid
1131121127Sjeffsched_clock(struct thread *td)
1132109864Sjeff{
1133113357Sjeff	struct kseq *kseq;
1134113357Sjeff	struct ksegrp *kg;
1135121127Sjeff	struct kse *ke;
1136109864Sjeff
1137113357Sjeff	/*
1138113357Sjeff	 * sched_setup() apparently happens prior to stathz being set.  We
1139113357Sjeff	 * need to resolve the timers earlier in the boot so we can avoid
1140113357Sjeff	 * calculating this here.
1141113357Sjeff	 */
1142113357Sjeff	if (realstathz == 0) {
1143113357Sjeff		realstathz = stathz ? stathz : hz;
1144113357Sjeff		tickincr = hz / realstathz;
1145113357Sjeff		/*
1146113357Sjeff		 * XXX This does not work for values of stathz that are much
1147113357Sjeff		 * larger than hz.
1148113357Sjeff		 */
1149113357Sjeff		if (tickincr == 0)
1150113357Sjeff			tickincr = 1;
1151113357Sjeff	}
1152109864Sjeff
1153121127Sjeff	ke = td->td_kse;
1154113357Sjeff	kg = ke->ke_ksegrp;
1155109864Sjeff
1156110028Sjeff	mtx_assert(&sched_lock, MA_OWNED);
1157110028Sjeff	KASSERT((td != NULL), ("schedclock: null thread pointer"));
1158110028Sjeff
1159110028Sjeff	/* Adjust ticks for pctcpu */
1160111793Sjeff	ke->ke_ticks++;
1161109971Sjeff	ke->ke_ltick = ticks;
1162112994Sjeff
1163109971Sjeff	/* Go up to one second beyond our max and then trim back down */
1164109971Sjeff	if (ke->ke_ftick + SCHED_CPU_TICKS + hz < ke->ke_ltick)
1165109971Sjeff		sched_pctcpu_update(ke);
1166109971Sjeff
1167114496Sjulian	if (td->td_flags & TDF_IDLETD)
1168109864Sjeff		return;
1169110028Sjeff
1170113357Sjeff	CTR4(KTR_ULE, "Tick kse %p (slice: %d, slptime: %d, runtime: %d)",
1171113357Sjeff	    ke, ke->ke_slice, kg->kg_slptime >> 10, kg->kg_runtime >> 10);
1172110028Sjeff	/*
1173113357Sjeff	 * We only do slicing code for TIMESHARE ksegrps.
1174113357Sjeff	 */
1175113357Sjeff	if (kg->kg_pri_class != PRI_TIMESHARE)
1176113357Sjeff		return;
1177113357Sjeff	/*
1178110645Sjeff	 * We used a tick charge it to the ksegrp so that we can compute our
1179113357Sjeff	 * interactivity.
1180109864Sjeff	 */
1181113357Sjeff	kg->kg_runtime += tickincr << 10;
1182116463Sjeff	sched_interact_update(kg);
1183110645Sjeff
1184109864Sjeff	/*
1185109864Sjeff	 * We used up one time slice.
1186109864Sjeff	 */
1187122847Sjeff	if (--ke->ke_slice > 0)
1188113357Sjeff		return;
1189109864Sjeff	/*
1190113357Sjeff	 * We're out of time, recompute priorities and requeue.
1191109864Sjeff	 */
1192122847Sjeff	kseq = KSEQ_SELF();
1193122744Sjeff	kseq_load_rem(kseq, ke);
1194113357Sjeff	sched_priority(kg);
1195113357Sjeff	sched_slice(ke);
1196113357Sjeff	if (SCHED_CURR(kg, ke))
1197113357Sjeff		ke->ke_runq = kseq->ksq_curr;
1198113357Sjeff	else
1199113357Sjeff		ke->ke_runq = kseq->ksq_next;
1200122744Sjeff	kseq_load_add(kseq, ke);
1201113357Sjeff	td->td_flags |= TDF_NEEDRESCHED;
1202109864Sjeff}
1203109864Sjeff
1204109864Sjeffint
1205109864Sjeffsched_runnable(void)
1206109864Sjeff{
1207109864Sjeff	struct kseq *kseq;
1208115998Sjeff	int load;
1209109864Sjeff
1210115998Sjeff	load = 1;
1211115998Sjeff
1212110028Sjeff	kseq = KSEQ_SELF();
1213121790Sjeff#ifdef SMP
1214122094Sjeff	if (kseq->ksq_assigned) {
1215122094Sjeff		mtx_lock_spin(&sched_lock);
1216121790Sjeff		kseq_assign(kseq);
1217122094Sjeff		mtx_unlock_spin(&sched_lock);
1218122094Sjeff	}
1219121790Sjeff#endif
1220121605Sjeff	if ((curthread->td_flags & TDF_IDLETD) != 0) {
1221121605Sjeff		if (kseq->ksq_load > 0)
1222121605Sjeff			goto out;
1223121605Sjeff	} else
1224121605Sjeff		if (kseq->ksq_load - 1 > 0)
1225121605Sjeff			goto out;
1226115998Sjeff	load = 0;
1227115998Sjeffout:
1228115998Sjeff	return (load);
1229109864Sjeff}
1230109864Sjeff
1231109864Sjeffvoid
1232109864Sjeffsched_userret(struct thread *td)
1233109864Sjeff{
1234109864Sjeff	struct ksegrp *kg;
1235121605Sjeff
1236121605Sjeff	kg = td->td_ksegrp;
1237109864Sjeff
1238109864Sjeff	if (td->td_priority != kg->kg_user_pri) {
1239109864Sjeff		mtx_lock_spin(&sched_lock);
1240109864Sjeff		td->td_priority = kg->kg_user_pri;
1241109864Sjeff		mtx_unlock_spin(&sched_lock);
1242109864Sjeff	}
1243109864Sjeff}
1244109864Sjeff
1245109864Sjeffstruct kse *
1246109970Sjeffsched_choose(void)
1247109970Sjeff{
1248110028Sjeff	struct kseq *kseq;
1249109970Sjeff	struct kse *ke;
1250109970Sjeff
1251115998Sjeff	mtx_assert(&sched_lock, MA_OWNED);
1252121790Sjeff	kseq = KSEQ_SELF();
1253113357Sjeff#ifdef SMP
1254121790Sjeff	if (kseq->ksq_assigned)
1255121790Sjeff		kseq_assign(kseq);
1256113357Sjeff#endif
1257121790Sjeff	ke = kseq_choose(kseq);
1258109864Sjeff	if (ke) {
1259121790Sjeff#ifdef SMP
1260121790Sjeff		if (ke->ke_ksegrp->kg_pri_class == PRI_IDLE)
1261121923Sjeff			kseq_setidle(kseq);
1262121790Sjeff#endif
1263122744Sjeff		kseq_runq_rem(kseq, ke);
1264109864Sjeff		ke->ke_state = KES_THREAD;
1265112966Sjeff
1266113357Sjeff		if (ke->ke_ksegrp->kg_pri_class == PRI_TIMESHARE) {
1267113357Sjeff			CTR4(KTR_ULE, "Run kse %p from %p (slice: %d, pri: %d)",
1268113357Sjeff			    ke, ke->ke_runq, ke->ke_slice,
1269113357Sjeff			    ke->ke_thread->td_priority);
1270113357Sjeff		}
1271113357Sjeff		return (ke);
1272109864Sjeff	}
1273109970Sjeff#ifdef SMP
1274121923Sjeff	kseq_setidle(kseq);
1275109970Sjeff#endif
1276113357Sjeff	return (NULL);
1277109864Sjeff}
1278109864Sjeff
1279109864Sjeffvoid
1280121127Sjeffsched_add(struct thread *td)
1281109864Sjeff{
1282110267Sjeff	struct kseq *kseq;
1283113357Sjeff	struct ksegrp *kg;
1284121127Sjeff	struct kse *ke;
1285121790Sjeff	int class;
1286109864Sjeff
1287121790Sjeff	mtx_assert(&sched_lock, MA_OWNED);
1288121127Sjeff	ke = td->td_kse;
1289121127Sjeff	kg = td->td_ksegrp;
1290121790Sjeff	if (ke->ke_flags & KEF_ASSIGNED)
1291121790Sjeff		return;
1292121790Sjeff	kseq = KSEQ_SELF();
1293110267Sjeff	KASSERT((ke->ke_thread != NULL), ("sched_add: No thread on KSE"));
1294109864Sjeff	KASSERT((ke->ke_thread->td_kse != NULL),
1295110267Sjeff	    ("sched_add: No KSE on thread"));
1296109864Sjeff	KASSERT(ke->ke_state != KES_ONRUNQ,
1297110267Sjeff	    ("sched_add: kse %p (%s) already in run queue", ke,
1298109864Sjeff	    ke->ke_proc->p_comm));
1299109864Sjeff	KASSERT(ke->ke_proc->p_sflag & PS_INMEM,
1300110267Sjeff	    ("sched_add: process swapped out"));
1301113387Sjeff	KASSERT(ke->ke_runq == NULL,
1302113387Sjeff	    ("sched_add: KSE %p is still assigned to a run queue", ke));
1303109864Sjeff
1304121790Sjeff	class = PRI_BASE(kg->kg_pri_class);
1305121790Sjeff	switch (class) {
1306112994Sjeff	case PRI_ITHD:
1307112994Sjeff	case PRI_REALTIME:
1308113357Sjeff		ke->ke_runq = kseq->ksq_curr;
1309113357Sjeff		ke->ke_slice = SCHED_SLICE_MAX;
1310113660Sjeff		ke->ke_cpu = PCPU_GET(cpuid);
1311112994Sjeff		break;
1312112994Sjeff	case PRI_TIMESHARE:
1313121790Sjeff#ifdef SMP
1314121790Sjeff		if (ke->ke_cpu != PCPU_GET(cpuid)) {
1315121790Sjeff			kseq_notify(ke, ke->ke_cpu);
1316121790Sjeff			return;
1317121790Sjeff		}
1318121790Sjeff#endif
1319113387Sjeff		if (SCHED_CURR(kg, ke))
1320113387Sjeff			ke->ke_runq = kseq->ksq_curr;
1321113387Sjeff		else
1322113387Sjeff			ke->ke_runq = kseq->ksq_next;
1323113357Sjeff		break;
1324112994Sjeff	case PRI_IDLE:
1325121790Sjeff#ifdef SMP
1326121790Sjeff		if (ke->ke_cpu != PCPU_GET(cpuid)) {
1327121790Sjeff			kseq_notify(ke, ke->ke_cpu);
1328121790Sjeff			return;
1329121790Sjeff		}
1330121790Sjeff#endif
1331113357Sjeff		/*
1332113357Sjeff		 * This is for priority prop.
1333113357Sjeff		 */
1334121605Sjeff		if (ke->ke_thread->td_priority < PRI_MIN_IDLE)
1335113357Sjeff			ke->ke_runq = kseq->ksq_curr;
1336113357Sjeff		else
1337113357Sjeff			ke->ke_runq = &kseq->ksq_idle;
1338113357Sjeff		ke->ke_slice = SCHED_SLICE_MIN;
1339112994Sjeff		break;
1340113357Sjeff	default:
1341121868Sjeff		panic("Unknown pri class.");
1342113357Sjeff		break;
1343112994Sjeff	}
1344121790Sjeff#ifdef SMP
1345121790Sjeff	/*
1346122744Sjeff	 * If there are any idle processors, give them our extra load.  The
1347122744Sjeff	 * threshold at which we start to reassign kses has a large impact
1348122744Sjeff	 * on the overall performance of the system.  Tuned too high and
1349122744Sjeff	 * some CPUs may idle.  Too low and there will be excess migration
1350122744Sjeff	 * and context swiches.
1351121790Sjeff	 */
1352122744Sjeff	if (kseq->ksq_load_transferable > kseq->ksq_cpus &&
1353122744Sjeff	    KSE_CAN_MIGRATE(ke, class) && kseq_idle) {
1354121790Sjeff		int cpu;
1355109864Sjeff
1356121790Sjeff		/*
1357121790Sjeff		 * Multiple cpus could find this bit simultaneously but the
1358121790Sjeff		 * race shouldn't be terrible.
1359121790Sjeff		 */
1360121790Sjeff		cpu = ffs(kseq_idle);
1361121790Sjeff		if (cpu) {
1362121790Sjeff			cpu--;
1363121790Sjeff			atomic_clear_int(&kseq_idle, 1 << cpu);
1364121790Sjeff			ke->ke_cpu = cpu;
1365121790Sjeff			ke->ke_runq = NULL;
1366121790Sjeff			kseq_notify(ke, cpu);
1367121790Sjeff			return;
1368121790Sjeff		}
1369121790Sjeff	}
1370121923Sjeff	if (kseq->ksq_idled &&
1371121923Sjeff	    (class == PRI_TIMESHARE || class == PRI_REALTIME)) {
1372121790Sjeff		atomic_clear_int(&kseq_idle, PCPU_GET(cpumask));
1373121923Sjeff		kseq->ksq_idled = 0;
1374121923Sjeff	}
1375121790Sjeff#endif
1376121790Sjeff        if (td->td_priority < curthread->td_priority)
1377121790Sjeff                curthread->td_flags |= TDF_NEEDRESCHED;
1378121790Sjeff
1379109864Sjeff	ke->ke_ksegrp->kg_runq_kses++;
1380109864Sjeff	ke->ke_state = KES_ONRUNQ;
1381109864Sjeff
1382122744Sjeff	kseq_runq_add(kseq, ke);
1383122744Sjeff	kseq_load_add(kseq, ke);
1384109864Sjeff}
1385109864Sjeff
1386109864Sjeffvoid
1387121127Sjeffsched_rem(struct thread *td)
1388109864Sjeff{
1389113357Sjeff	struct kseq *kseq;
1390121127Sjeff	struct kse *ke;
1391113357Sjeff
1392121127Sjeff	ke = td->td_kse;
1393121790Sjeff	/*
1394121790Sjeff	 * It is safe to just return here because sched_rem() is only ever
1395121790Sjeff	 * used in places where we're immediately going to add the
1396121790Sjeff	 * kse back on again.  In that case it'll be added with the correct
1397121790Sjeff	 * thread and priority when the caller drops the sched_lock.
1398121790Sjeff	 */
1399121790Sjeff	if (ke->ke_flags & KEF_ASSIGNED)
1400121790Sjeff		return;
1401109864Sjeff	mtx_assert(&sched_lock, MA_OWNED);
1402113387Sjeff	KASSERT((ke->ke_state == KES_ONRUNQ), ("KSE not on run queue"));
1403109864Sjeff
1404109864Sjeff	ke->ke_state = KES_THREAD;
1405109864Sjeff	ke->ke_ksegrp->kg_runq_kses--;
1406113357Sjeff	kseq = KSEQ_CPU(ke->ke_cpu);
1407122744Sjeff	kseq_runq_rem(kseq, ke);
1408122744Sjeff	kseq_load_rem(kseq, ke);
1409109864Sjeff}
1410109864Sjeff
1411109864Sjefffixpt_t
1412121127Sjeffsched_pctcpu(struct thread *td)
1413109864Sjeff{
1414109864Sjeff	fixpt_t pctcpu;
1415121127Sjeff	struct kse *ke;
1416109864Sjeff
1417109864Sjeff	pctcpu = 0;
1418121127Sjeff	ke = td->td_kse;
1419121290Sjeff	if (ke == NULL)
1420121290Sjeff		return (0);
1421109864Sjeff
1422115998Sjeff	mtx_lock_spin(&sched_lock);
1423109864Sjeff	if (ke->ke_ticks) {
1424109864Sjeff		int rtick;
1425109864Sjeff
1426116365Sjeff		/*
1427116365Sjeff		 * Don't update more frequently than twice a second.  Allowing
1428116365Sjeff		 * this causes the cpu usage to decay away too quickly due to
1429116365Sjeff		 * rounding errors.
1430116365Sjeff		 */
1431116365Sjeff		if (ke->ke_ltick < (ticks - (hz / 2)))
1432116365Sjeff			sched_pctcpu_update(ke);
1433109864Sjeff		/* How many rtick per second ? */
1434116365Sjeff		rtick = min(ke->ke_ticks / SCHED_CPU_TIME, SCHED_CPU_TICKS);
1435110226Sscottl		pctcpu = (FSCALE * ((FSCALE * rtick)/realstathz)) >> FSHIFT;
1436109864Sjeff	}
1437109864Sjeff
1438109864Sjeff	ke->ke_proc->p_swtime = ke->ke_ltick - ke->ke_ftick;
1439113865Sjhb	mtx_unlock_spin(&sched_lock);
1440109864Sjeff
1441109864Sjeff	return (pctcpu);
1442109864Sjeff}
1443109864Sjeff
1444122038Sjeffvoid
1445122038Sjeffsched_bind(struct thread *td, int cpu)
1446122038Sjeff{
1447122038Sjeff	struct kse *ke;
1448122038Sjeff
1449122038Sjeff	mtx_assert(&sched_lock, MA_OWNED);
1450122038Sjeff	ke = td->td_kse;
1451122038Sjeff#ifndef SMP
1452122038Sjeff	ke->ke_flags |= KEF_BOUND;
1453122038Sjeff#else
1454122038Sjeff	if (PCPU_GET(cpuid) == cpu) {
1455122038Sjeff		ke->ke_flags |= KEF_BOUND;
1456122038Sjeff		return;
1457122038Sjeff	}
1458122038Sjeff	/* sched_rem without the runq_remove */
1459122038Sjeff	ke->ke_state = KES_THREAD;
1460122038Sjeff	ke->ke_ksegrp->kg_runq_kses--;
1461122744Sjeff	kseq_load_rem(KSEQ_CPU(ke->ke_cpu), ke);
1462122038Sjeff	ke->ke_cpu = cpu;
1463122038Sjeff	kseq_notify(ke, cpu);
1464122038Sjeff	/* When we return from mi_switch we'll be on the correct cpu. */
1465122038Sjeff	td->td_proc->p_stats->p_ru.ru_nvcsw++;
1466122038Sjeff	mi_switch();
1467122038Sjeff#endif
1468122038Sjeff}
1469122038Sjeff
1470122038Sjeffvoid
1471122038Sjeffsched_unbind(struct thread *td)
1472122038Sjeff{
1473122038Sjeff	mtx_assert(&sched_lock, MA_OWNED);
1474122038Sjeff	td->td_kse->ke_flags &= ~KEF_BOUND;
1475122038Sjeff}
1476122038Sjeff
1477109864Sjeffint
1478109864Sjeffsched_sizeof_kse(void)
1479109864Sjeff{
1480109864Sjeff	return (sizeof(struct kse) + sizeof(struct ke_sched));
1481109864Sjeff}
1482109864Sjeff
1483109864Sjeffint
1484109864Sjeffsched_sizeof_ksegrp(void)
1485109864Sjeff{
1486109864Sjeff	return (sizeof(struct ksegrp) + sizeof(struct kg_sched));
1487109864Sjeff}
1488109864Sjeff
1489109864Sjeffint
1490109864Sjeffsched_sizeof_proc(void)
1491109864Sjeff{
1492109864Sjeff	return (sizeof(struct proc));
1493109864Sjeff}
1494109864Sjeff
1495109864Sjeffint
1496109864Sjeffsched_sizeof_thread(void)
1497109864Sjeff{
1498109864Sjeff	return (sizeof(struct thread) + sizeof(struct td_sched));
1499109864Sjeff}
1500