[apple/xnu.git] / osfmk / kern / sched.h

/*
 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */
/*
 *	File:	sched.h
 *	Author:	Avadis Tevanian, Jr.
 *	Date:	1985
 *
 *	Header file for scheduler.
 *
 */

#ifndef	_KERN_SCHED_H_
#define _KERN_SCHED_H_

#include <stat_time.h>

#include <mach/policy.h>
#include <kern/kern_types.h>
#include <kern/queue.h>
#include <kern/lock.h>
#include <kern/macro_help.h>
#include <kern/timer_call.h>
#include <kern/ast.h>

#define	NRQS		128				/* 128 levels per run queue */
#define NRQBM		(NRQS / 32)		/* number of words per bit map */

#define MAXPRI		(NRQS-1)
#define MINPRI		IDLEPRI			/* lowest legal priority schedulable */
#define	IDLEPRI		0				/* idle thread priority */
#define DEPRESSPRI	MINPRI			/* depress priority */

/*
 *	High-level priority assignments
 *
 *************************************************************************
 * 127		Reserved (real-time)
 *				A
 *				+
 *			(32 levels)
 *				+
 *				V
 * 96		Reserved (real-time)
 * 95		Kernel mode only
 *				A
 *				+
 *			(16 levels)
 *				+
 *				V
 * 80		Kernel mode only
 * 79		System high priority
 *				A
 *				+
 *			(16 levels)
 *				+
 *				V
 * 64		System high priority
 * 63		Elevated priorities
 *				A
 *				+
 *			(12 levels)
 *				+
 *				V
 * 52		Elevated priorities
 * 51		Elevated priorities (incl. BSD +nice)
 *				A
 *				+
 *			(20 levels)
 *				+
 *				V
 * 32		Elevated priorities (incl. BSD +nice)
 * 31		Default (default base for threads)
 * 30		Lowered priorities (incl. BSD -nice)
 *				A
 *				+
 *			(20 levels)
 *				+
 *				V
 * 11		Lowered priorities (incl. BSD -nice)
 * 10		Lowered priorities (aged pri's)
 *				A
 *				+
 *			(11 levels)
 *				+
 *				V
 * 0		Lowered priorities (aged pri's / idle)
 *************************************************************************
 */

#define BASEPRI_RTQUEUES	(BASEPRI_REALTIME + 1)				/* 97 */
#define BASEPRI_REALTIME	(MAXPRI - (NRQS / 4) + 1)			/* 96 */

#define MAXPRI_KERNEL		(BASEPRI_REALTIME - 1)				/* 95 */
#define BASEPRI_PREEMPT		(MAXPRI_KERNEL - 2)					/* 93 */
#define BASEPRI_KERNEL		(MINPRI_KERNEL + 1)					/* 81 */
#define MINPRI_KERNEL		(MAXPRI_KERNEL - (NRQS / 8) + 1)	/* 80 */

#define MAXPRI_RESERVED		(MINPRI_KERNEL - 1)					/* 79 */
#define MINPRI_RESERVED		(MAXPRI_RESERVED - (NRQS / 8) + 1)	/* 64 */

#define MAXPRI_USER			(MINPRI_RESERVED - 1)				/* 63 */
#define BASEPRI_CONTROL		(BASEPRI_DEFAULT + 17)				/* 48 */
#define BASEPRI_FOREGROUND	(BASEPRI_DEFAULT + 16)				/* 47 */
#define BASEPRI_BACKGROUND	(BASEPRI_DEFAULT + 15)				/* 46 */
#define BASEPRI_DEFAULT		(MAXPRI_USER - (NRQS / 4))			/* 31 */
#define MINPRI_USER			MINPRI								/*  0 */

/*
 *	Macro to check for invalid priorities.
 */
#define invalid_pri(pri) ((pri) < MINPRI || (pri) > MAXPRI)

struct run_queue {
	int					highq;				/* highest runnable queue */
	int					bitmap[NRQBM];		/* run queue bitmap array */
	int					count;				/* # of threads total */
	int					urgency;			/* level of preemption urgency */
	queue_head_t		queues[NRQS];		/* one for each priority */
};

typedef struct run_queue	*run_queue_t;
#define RUN_QUEUE_NULL		((run_queue_t) 0)

#define first_timeslice(processor)		((processor)->timeslice > 0)

#define	processor_timeslice_setup(processor, thread)			\
MACRO_BEGIN														\
	(processor)->timeslice =									\
		((thread)->sched_mode & TH_MODE_TIMESHARE)?				\
			(processor)->processor_set->timeshare_quanta: 1;	\
MACRO_END

#define thread_quantum_init(thread)							\
MACRO_BEGIN													\
	(thread)->current_quantum = 							\
		((thread)->sched_mode & TH_MODE_REALTIME)?			\
			(thread)->realtime.computation: std_quantum;	\
MACRO_END

/* Invoked at splsched by a thread on itself */
#define csw_needed(thread, processor) (										\
	((thread)->state & TH_SUSP)										||		\
	(first_timeslice(processor)?											\
	 ((processor)->runq.highq > (thread)->sched_pri				||			\
	  (processor)->processor_set->runq.highq > (thread)->sched_pri) :		\
	 ((processor)->runq.highq >= (thread)->sched_pri			||			\
	  (processor)->processor_set->runq.highq >= (thread)->sched_pri))	)

/*
 *	Scheduler routines.
 */

/* Remove thread from its run queue */
extern run_queue_t	run_queue_remove(
						thread_t	thread);

/* Handle quantum expiration for an executing thread */
extern void		thread_quantum_expire(
					timer_call_param_t	processor,
					timer_call_param_t	thread);

/* Called at splsched by a thread on itself */
extern ast_t	csw_check(
					thread_t		thread,
					processor_t		processor);

extern uint32_t	std_quantum, min_std_quantum;
extern uint32_t	std_quantum_us;

extern uint32_t	max_rt_quantum, min_rt_quantum;

extern uint32_t	sched_cswtime;

/*
 *	Age usage (1 << SCHED_TICK_SHIFT) times per second.
 */
#define SCHED_TICK_SHIFT	3

extern unsigned		sched_tick;
extern uint32_t		sched_tick_interval;

/* Periodic computation of various averages */
extern void		compute_averages(void);

extern void		compute_averunnable(
					void			*nrun);

extern void		compute_stack_target(
					void			*arg);

/*
 *	Conversion factor from usage
 *	to priority.
 */
extern uint32_t		sched_pri_shift;

/*
 *	Scaling factor for usage
 *	based on load.
 */
extern int8_t		sched_load_shifts[NRQS];

extern int32_t		sched_poll_yield_shift;
extern uint32_t		sched_safe_duration;

extern uint64_t		max_unsafe_computation;
extern uint64_t		max_poll_computation;

extern uint32_t		avenrun[3], mach_factor[3];

/*
 *	thread_timer_delta macro takes care of both thread timers.
 */
#define thread_timer_delta(thread, delta)					\
MACRO_BEGIN													\
	(delta) = timer_delta(&(thread)->system_timer,			\
							&(thread)->system_timer_save);	\
	(delta) += timer_delta(&(thread)->user_timer,			\
							&(thread)->user_timer_save);	\
MACRO_END

#endif	/* _KERN_SCHED_H_ */
Commit	Line	Data
1c79356b	1	/*
91447636	2	* Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
1c79356b	3	*
8f6c56a5	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
8f6c56a5 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
8ad349bb	24	* limitations under the License.
8f6c56a5 A	25	*
8f6c56a5 A	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
	28	/*
	29	* @OSF_COPYRIGHT@
	30	*/
	31	/*
	32	* Mach Operating System
	33	* Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
	34	* All Rights Reserved.
	35	*
	36	* Permission to use, copy, modify and distribute this software and its
	37	* documentation is hereby granted, provided that both the copyright
	38	* notice and this permission notice appear in all copies of the
	39	* software, derivative works or modified versions, and any portions
	40	* thereof, and that both notices appear in supporting documentation.
	41	*
	42	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	43	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	44	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	45	*
	46	* Carnegie Mellon requests users of this software to return to
	47	*
	48	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	49	* School of Computer Science
	50	* Carnegie Mellon University
	51	* Pittsburgh PA 15213-3890
	52	*
	53	* any improvements or extensions that they make and grant Carnegie Mellon
	54	* the rights to redistribute these changes.
	55	*/
	56	/*
	57	*/
	58	/*
	59	* File: sched.h
	60	* Author: Avadis Tevanian, Jr.
	61	* Date: 1985
	62	*
	63	* Header file for scheduler.
	64	*
	65	*/
	66
	67	#ifndef _KERN_SCHED_H_
	68	#define _KERN_SCHED_H_
	69
1c79356b A	70	#include <stat_time.h>
	71
	72	#include <mach/policy.h>
	73	#include <kern/kern_types.h>
	74	#include <kern/queue.h>
	75	#include <kern/lock.h>
	76	#include <kern/macro_help.h>
0b4e3aa0	77	#include <kern/timer_call.h>
9bccf70c	78	#include <kern/ast.h>
1c79356b	79
9bccf70c A	80	#define NRQS 128 /* 128 levels per run queue */
9bccf70c A	81	#define NRQBM (NRQS / 32) /* number of words per bit map */
1c79356b A	82
	83	#define MAXPRI (NRQS-1)
	84	#define MINPRI IDLEPRI /* lowest legal priority schedulable */
	85	#define IDLEPRI 0 /* idle thread priority */
	86	#define DEPRESSPRI MINPRI /* depress priority */
	87
	88	/*
	89	* High-level priority assignments
	90	*
	91	*************************************************************************
	92	* 127 Reserved (real-time)
	93	* A
	94	* +
	95	* (32 levels)
	96	* +
	97	* V
	98	* 96 Reserved (real-time)
	99	* 95 Kernel mode only
	100	* A
	101	* +
	102	* (16 levels)
	103	* +
	104	* V
	105	* 80 Kernel mode only
0b4e3aa0	106	* 79 System high priority
1c79356b A	107	* A
	108	* +
	109	* (16 levels)
	110	* +
	111	* V
0b4e3aa0	112	* 64 System high priority
1c79356b A	113	* 63 Elevated priorities
	114	* A
	115	* +
	116	* (12 levels)
	117	* +
	118	* V
	119	* 52 Elevated priorities
	120	* 51 Elevated priorities (incl. BSD +nice)
	121	* A
	122	* +
	123	* (20 levels)
	124	* +
	125	* V
	126	* 32 Elevated priorities (incl. BSD +nice)
	127	* 31 Default (default base for threads)
	128	* 30 Lowered priorities (incl. BSD -nice)
	129	* A
	130	* +
	131	* (20 levels)
	132	* +
	133	* V
	134	* 11 Lowered priorities (incl. BSD -nice)
	135	* 10 Lowered priorities (aged pri's)
	136	* A
	137	* +
	138	* (11 levels)
	139	* +
	140	* V
	141	* 0 Lowered priorities (aged pri's / idle)
	142	*************************************************************************
	143	*/
	144
55e303ae	145	#define BASEPRI_RTQUEUES (BASEPRI_REALTIME + 1) /* 97 */
1c79356b A	146	#define BASEPRI_REALTIME (MAXPRI - (NRQS / 4) + 1) /* 96 */
1c79356b A	147
91447636	148	#define MAXPRI_KERNEL (BASEPRI_REALTIME - 1) /* 95 */
0b4e3aa0	149	#define BASEPRI_PREEMPT (MAXPRI_KERNEL - 2) /* 93 */
55e303ae	150	#define BASEPRI_KERNEL (MINPRI_KERNEL + 1) /* 81 */
0b4e3aa0	151	#define MINPRI_KERNEL (MAXPRI_KERNEL - (NRQS / 8) + 1) /* 80 */
1c79356b	152
91447636 A	153	#define MAXPRI_RESERVED (MINPRI_KERNEL - 1) /* 79 */
91447636 A	154	#define MINPRI_RESERVED (MAXPRI_RESERVED - (NRQS / 8) + 1) /* 64 */
1c79356b	155
91447636	156	#define MAXPRI_USER (MINPRI_RESERVED - 1) /* 63 */
9bccf70c A	157	#define BASEPRI_CONTROL (BASEPRI_DEFAULT + 17) /* 48 */
	158	#define BASEPRI_FOREGROUND (BASEPRI_DEFAULT + 16) /* 47 */
	159	#define BASEPRI_BACKGROUND (BASEPRI_DEFAULT + 15) /* 46 */
0b4e3aa0 A	160	#define BASEPRI_DEFAULT (MAXPRI_USER - (NRQS / 4)) /* 31 */
0b4e3aa0 A	161	#define MINPRI_USER MINPRI /* 0 */
1c79356b	162
1c79356b A	163	/*
	164	* Macro to check for invalid priorities.
	165	*/
	166	#define invalid_pri(pri) ((pri) < MINPRI \|\| (pri) > MAXPRI)
	167
	168	struct run_queue {
1c79356b	169	int highq; /* highest runnable queue */
55e303ae A	170	int bitmap[NRQBM]; /* run queue bitmap array */
55e303ae A	171	int count; /* # of threads total */
9bccf70c	172	int urgency; /* level of preemption urgency */
55e303ae	173	queue_head_t queues[NRQS]; /* one for each priority */
1c79356b A	174	};
	175
	176	typedef struct run_queue *run_queue_t;
	177	#define RUN_QUEUE_NULL ((run_queue_t) 0)
	178
55e303ae A	179	#define first_timeslice(processor) ((processor)->timeslice > 0)
	180
	181	#define processor_timeslice_setup(processor, thread) \
	182	MACRO_BEGIN \
	183	(processor)->timeslice = \
	184	((thread)->sched_mode & TH_MODE_TIMESHARE)? \
	185	(processor)->processor_set->timeshare_quanta: 1; \
	186	MACRO_END
	187
	188	#define thread_quantum_init(thread) \
	189	MACRO_BEGIN \
	190	(thread)->current_quantum = \
	191	((thread)->sched_mode & TH_MODE_REALTIME)? \
	192	(thread)->realtime.computation: std_quantum; \
	193	MACRO_END
0b4e3aa0	194
9bccf70c	195	/* Invoked at splsched by a thread on itself */
1c79356b A	196	#define csw_needed(thread, processor) ( \
1c79356b A	197	((thread)->state & TH_SUSP) \|\| \
55e303ae	198	(first_timeslice(processor)? \
1c79356b A	199	((processor)->runq.highq > (thread)->sched_pri \|\| \
	200	(processor)->processor_set->runq.highq > (thread)->sched_pri) : \
	201	((processor)->runq.highq >= (thread)->sched_pri \|\| \
	202	(processor)->processor_set->runq.highq >= (thread)->sched_pri)) )
	203
	204	/*
	205	* Scheduler routines.
	206	*/
	207
	208	/* Remove thread from its run queue */
55e303ae	209	extern run_queue_t run_queue_remove(
0b4e3aa0	210	thread_t thread);
1c79356b	211
0b4e3aa0 A	212	/* Handle quantum expiration for an executing thread */
	213	extern void thread_quantum_expire(
	214	timer_call_param_t processor,
	215	timer_call_param_t thread);
	216
9bccf70c A	217	/* Called at splsched by a thread on itself */
	218	extern ast_t csw_check(
	219	thread_t thread,
	220	processor_t processor);
	221
0b4e3aa0 A	222	extern uint32_t std_quantum, min_std_quantum;
0b4e3aa0 A	223	extern uint32_t std_quantum_us;
1c79356b	224
0b4e3aa0	225	extern uint32_t max_rt_quantum, min_rt_quantum;
1c79356b	226
91447636 A	227	extern uint32_t sched_cswtime;
91447636 A	228
1c79356b	229	/*
91447636	230	* Age usage (1 << SCHED_TICK_SHIFT) times per second.
1c79356b	231	*/
91447636 A	232	#define SCHED_TICK_SHIFT 3
	233
	234	extern unsigned sched_tick;
	235	extern uint32_t sched_tick_interval;
	236
	237	/* Periodic computation of various averages */
	238	extern void compute_averages(void);
1c79356b	239
91447636 A	240	extern void compute_averunnable(
	241	void *nrun);
	242
	243	extern void compute_stack_target(
	244	void *arg);
1c79356b A	245
1c79356b A	246	/*
91447636 A	247	* Conversion factor from usage
	248	* to priority.
	249	*/
	250	extern uint32_t sched_pri_shift;
	251
	252	/*
	253	* Scaling factor for usage
	254	* based on load.
1c79356b	255	*/
91447636	256	extern int8_t sched_load_shifts[NRQS];
1c79356b	257
91447636 A	258	extern int32_t sched_poll_yield_shift;
91447636 A	259	extern uint32_t sched_safe_duration;
1c79356b	260
91447636 A	261	extern uint64_t max_unsafe_computation;
91447636 A	262	extern uint64_t max_poll_computation;
1c79356b	263
91447636	264	extern uint32_t avenrun[3], mach_factor[3];
1c79356b A	265
	266	/*
	267	* thread_timer_delta macro takes care of both thread timers.
	268	*/
91447636	269	#define thread_timer_delta(thread, delta) \
1c79356b	270	MACRO_BEGIN \
91447636 A	271	(delta) = timer_delta(&(thread)->system_timer, \
	272	&(thread)->system_timer_save); \
	273	(delta) += timer_delta(&(thread)->user_timer, \
	274	&(thread)->user_timer_save); \
1c79356b A	275	MACRO_END
1c79356b A	276
1c79356b	277	#endif /* _KERN_SCHED_H_ */