/* * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This 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 OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_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 <cpus.h> #include <simple_clock.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> #if STAT_TIME /* * Statistical timing uses microseconds as timer units. 16 bit shift * yields priorities. PRI_SHIFT_2 isn't needed. */ #define PRI_SHIFT (16 - SCHED_TICK_SHIFT) #else /* STAT_TIME */ /* * Otherwise machine provides shift(s) based on time units it uses. */ #include <machine/sched_param.h> #endif /* STAT_TIME */ #define NRQS 128 /* 128 run queues per cpu */ #define NRQBM (NRQS / 32) /* number of run queue bit maps */ #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 High priority * A * + * (16 levels) * + * V * 64 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_REALTIME (MAXPRI - (NRQS / 4) + 1) /* 96 */ #define MAXPRI_STANDARD (BASEPRI_REALTIME - 1) /* 95 */ #define MAXPRI_KERNBAND MAXPRI_STANDARD /* 95 */ #define MINPRI_KERNBAND (MAXPRI_KERNBAND - (NRQS / 8) + 1) /* 80 */ #define MAXPRI_HIGHBAND (MINPRI_KERNBAND - 1) /* 79 */ #define MINPRI_HIGHBAND (MAXPRI_HIGHBAND - (NRQS / 8) + 1) /* 64 */ #define MAXPRI_MAINBAND (MINPRI_HIGHBAND - 1) /* 63 */ #define BASEPRI_DEFAULT (MAXPRI_MAINBAND - (NRQS / 4)) /* 31 */ #define MINPRI_MAINBAND MINPRI /* 0 */ #define MINPRI_STANDARD MINPRI_MAINBAND /* 0 */ /* * Macro to check for invalid priorities. */ #define invalid_pri(pri) ((pri) < MINPRI || (pri) > MAXPRI) struct run_queue { queue_head_t queues[NRQS]; /* one for each priority */ decl_simple_lock_data(,lock) /* one lock for all queues */ int bitmap[NRQBM]; /* run queue bitmap array */ int highq; /* highest runnable queue */ int count; /* # of runnable threads */ }; typedef struct run_queue *run_queue_t; #define RUN_QUEUE_NULL ((run_queue_t) 0) #define csw_needed(thread, processor) ( \ ((thread)->state & TH_SUSP) || \ ((processor)->first_quantum? \ ((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 rem_runq( thread_t thread); /* Mach factor computation (in mach_factor.c) */ extern void compute_mach_factor(void); /* Update threads quantum (in priority.c) */ extern void thread_quantum_update( int mycpu, thread_t thread, int nticks, int state); extern int min_quantum; /* defines max context switch rate */ /* * Shift structures for holding update shifts. Actual computation * is usage = (usage >> shift1) +/- (usage >> abs(shift2)) where the * +/- is determined by the sign of shift 2. */ struct shift { int shift1; int shift2; }; typedef struct shift *shift_t, shift_data_t; /* * Age usage (1 << SCHED_TICK_SHIFT) times per second. */ extern unsigned sched_tick; #define SCHED_TICK_SHIFT 3 #define SCHED_SCALE 128 #define SCHED_SHIFT 7 /* * thread_timer_delta macro takes care of both thread timers. */ #define thread_timer_delta(thread) \ MACRO_BEGIN \ register unsigned delta; \ \ delta = 0; \ TIMER_DELTA((thread)->system_timer, \ (thread)->system_timer_save, delta); \ TIMER_DELTA((thread)->user_timer, \ (thread)->user_timer_save, delta); \ (thread)->cpu_delta += delta; \ (thread)->sched_delta += (delta * \ (thread)->processor_set->sched_load); \ MACRO_END #if SIMPLE_CLOCK /* * sched_usec is an exponential average of number of microseconds * in a second for clock drift compensation. */ extern int sched_usec; #endif /* SIMPLE_CLOCK */ #endif /* _KERN_SCHED_H_ */