xref: /minix/sys/sys/sched.h (revision 6c8f7fc3)
1 /*	$NetBSD: sched.h,v 1.75 2011/11/21 04:36:05 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1999, 2000, 2001, 2002, 2007, 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Ross Harvey, Jason R. Thorpe, Nathan J. Williams, Andrew Doran and
9  * Daniel Sieger.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 /*-
34  * Copyright (c) 1982, 1986, 1991, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  * (c) UNIX System Laboratories, Inc.
37  * All or some portions of this file are derived from material licensed
38  * to the University of California by American Telephone and Telegraph
39  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
40  * the permission of UNIX System Laboratories, Inc.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. Neither the name of the University nor the names of its contributors
51  *    may be used to endorse or promote products derived from this software
52  *    without specific prior written permission.
53  *
54  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64  * SUCH DAMAGE.
65  *
66  *	@(#)kern_clock.c	8.5 (Berkeley) 1/21/94
67  */
68 
69 #ifndef	_SYS_SCHED_H_
70 #define	_SYS_SCHED_H_
71 
72 #include <sys/featuretest.h>
73 #include <sys/types.h>
74 
75 #if defined(_KERNEL_OPT)
76 #include "opt_multiprocessor.h"
77 #include "opt_lockdebug.h"
78 #endif
79 
80 struct sched_param {
81 	int	sched_priority;
82 };
83 
84 /*
85  * Scheduling policies required by IEEE Std 1003.1-2001
86  */
87 #define	SCHED_NONE	-1
88 #define	SCHED_OTHER	0
89 #define	SCHED_FIFO	1
90 #define	SCHED_RR	2
91 
92 #if defined(_NETBSD_SOURCE)
93 __BEGIN_DECLS
94 
95 /*
96  * Interface of CPU-sets.
97  */
98 typedef struct _cpuset cpuset_t;
99 
100 #ifndef _KERNEL
101 
102 #define	cpuset_create()		_cpuset_create()
103 #define	cpuset_destroy(c)	_cpuset_destroy(c)
104 #define	cpuset_size(c)		_cpuset_size(c)
105 #define	cpuset_zero(c)		_cpuset_zero(c)
106 #define	cpuset_isset(i, c)	_cpuset_isset(i, c)
107 #define	cpuset_set(i, c)	_cpuset_set(i, c)
108 #define	cpuset_clr(i, c)	_cpuset_clr(i, c)
109 
110 cpuset_t *_cpuset_create(void);
111 void	_cpuset_destroy(cpuset_t *);
112 void	_cpuset_zero(cpuset_t *);
113 int	_cpuset_set(cpuid_t, cpuset_t *);
114 int	_cpuset_clr(cpuid_t, cpuset_t *);
115 int	_cpuset_isset(cpuid_t, const cpuset_t *);
116 size_t	_cpuset_size(const cpuset_t *);
117 
118 #endif
119 
120 /*
121  * Internal affinity and scheduling calls.
122  */
123 int	_sched_getaffinity(pid_t, lwpid_t, size_t, cpuset_t *);
124 int	_sched_setaffinity(pid_t, lwpid_t, size_t, const cpuset_t *);
125 int	_sched_getparam(pid_t, lwpid_t, int *, struct sched_param *);
126 int	_sched_setparam(pid_t, lwpid_t, int, const struct sched_param *);
127 __END_DECLS
128 
129 /*
130  * CPU states.
131  * XXX Not really scheduler state, but no other good place to put
132  * it right now, and it really is per-CPU.
133  */
134 #define	CP_USER		0
135 #define	CP_NICE		1
136 #define	CP_SYS		2
137 #define	CP_INTR		3
138 #define	CP_IDLE		4
139 #define	CPUSTATES	5
140 
141 #if defined(_KERNEL) || defined(_KMEMUSER)
142 
143 #include <sys/mutex.h>
144 #include <sys/time.h>
145 
146 /*
147  * Per-CPU scheduler state.  Field markings and the corresponding locks:
148  *
149  * s:	splsched, may only be safely accessed by the CPU itself
150  * m:	spc_mutex
151  * (:	unlocked, stable
152  * c:	cpu_lock
153  */
154 struct schedstate_percpu {
155 	/* First set of data is likely to be accessed by other CPUs. */
156 	kmutex_t	*spc_mutex;	/* (: lock on below, runnable LWPs */
157 	kmutex_t	*spc_lwplock;	/* (: general purpose lock for LWPs */
158 	struct lwp	*spc_migrating;	/* (: migrating LWP */
159 	pri_t		spc_curpriority;/* m: usrpri of curlwp */
160 	pri_t		spc_maxpriority;/* m: highest priority queued */
161 	psetid_t	spc_psid;	/* c: processor-set ID */
162 	time_t		spc_lastmod;	/* c: time of last cpu state change */
163 
164 	/* For the most part, this set of data is CPU-private. */
165 	void		*spc_sched_info;/* (: scheduler-specific structure */
166 	volatile int	spc_flags;	/* s: flags; see below */
167 	u_int		spc_schedticks;	/* s: ticks for schedclock() */
168 	uint64_t	spc_cp_time[CPUSTATES];/* s: CPU state statistics */
169 	int		spc_ticks;	/* s: ticks until sched_tick() */
170 	int		spc_pscnt;	/* s: prof/stat counter */
171 	int		spc_psdiv;	/* s: prof/stat divisor */
172 };
173 
174 /* spc_flags */
175 #define	SPCF_SEENRR		0x0001	/* process has seen roundrobin() */
176 #define	SPCF_SHOULDYIELD	0x0002	/* process should yield the CPU */
177 #define	SPCF_OFFLINE		0x0004	/* CPU marked offline */
178 #define	SPCF_RUNNING		0x0008	/* CPU is running */
179 #define	SPCF_NOINTR		0x0010	/* shielded from interrupts */
180 
181 #define	SPCF_SWITCHCLEAR	(SPCF_SEENRR|SPCF_SHOULDYIELD)
182 
183 #endif /* defined(_KERNEL) || defined(_KMEMUSER) */
184 
185 /*
186  * Flags passed to the Linux-compatible __clone(2) system call.
187  */
188 #define	CLONE_CSIGNAL		0x000000ff	/* signal to be sent at exit */
189 #define	CLONE_VM		0x00000100	/* share address space */
190 #define	CLONE_FS		0x00000200	/* share "file system" info */
191 #define	CLONE_FILES		0x00000400	/* share file descriptors */
192 #define	CLONE_SIGHAND		0x00000800	/* share signal actions */
193 #define	CLONE_PID		0x00001000	/* share process ID */
194 #define	CLONE_PTRACE		0x00002000	/* ptrace(2) continues on
195 						   child */
196 #define	CLONE_VFORK		0x00004000	/* parent blocks until child
197 						   exits */
198 
199 #endif /* _NETBSD_SOURCE */
200 
201 #ifdef _KERNEL
202 
203 extern int schedhz;			/* ideally: 16 */
204 
205 struct proc;
206 struct cpu_info;
207 
208 /*
209  * Common Scheduler Interface.
210  */
211 
212 /* Scheduler initialization */
213 void		runq_init(void);
214 void		synch_init(void);
215 void		sched_init(void);
216 void		sched_rqinit(void);
217 void		sched_cpuattach(struct cpu_info *);
218 
219 /* Time-driven events */
220 void		sched_tick(struct cpu_info *);
221 void		schedclock(struct lwp *);
222 void		sched_schedclock(struct lwp *);
223 void		sched_pstats(void);
224 void		sched_lwp_stats(struct lwp *);
225 void		sched_pstats_hook(struct lwp *, int);
226 
227 /* Runqueue-related functions */
228 bool		sched_curcpu_runnable_p(void);
229 void		sched_dequeue(struct lwp *);
230 void		sched_enqueue(struct lwp *, bool);
231 struct lwp *	sched_nextlwp(void);
232 void		sched_oncpu(struct lwp *);
233 void		sched_newts(struct lwp *);
234 
235 /* Priority adjustment */
236 void		sched_nice(struct proc *, int);
237 
238 /* Handlers of fork and exit */
239 void		sched_proc_fork(struct proc *, struct proc *);
240 void		sched_proc_exit(struct proc *, struct proc *);
241 void		sched_lwp_fork(struct lwp *, struct lwp *);
242 void		sched_lwp_collect(struct lwp *);
243 
244 void		sched_slept(struct lwp *);
245 void		sched_wakeup(struct lwp *);
246 
247 void		setrunnable(struct lwp *);
248 void		sched_setrunnable(struct lwp *);
249 
250 struct cpu_info *sched_takecpu(struct lwp *);
251 void		sched_print_runqueue(void (*pr)(const char *, ...)
252     __printflike(1, 2));
253 
254 /* Dispatching */
255 bool		kpreempt(uintptr_t);
256 void		preempt(void);
257 void		yield(void);
258 int		mi_switch(struct lwp *);
259 void		updatertime(lwp_t *, const struct bintime *);
260 void		sched_idle(void);
261 void		suspendsched(void);
262 
263 int		do_sched_setparam(pid_t, lwpid_t, int, const struct sched_param *);
264 int		do_sched_getparam(pid_t, lwpid_t, int *, struct sched_param *);
265 
266 #endif	/* _KERNEL */
267 #endif	/* _SYS_SCHED_H_ */
268