/* * 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: clock_prim.c * Author: Avadis Tevanian, Jr. * Date: 1986 * * Clock primitives. */ #include <cpus.h> #include <mach/boolean.h> #include <mach/kern_return.h> #include <mach/machine.h> #include <kern/host.h> #include <kern/mach_param.h> #include <kern/sched.h> #include <kern/spl.h> #include <kern/thread.h> #include <kern/processor.h> #include <machine/machparam.h> /* * thread_quantum_expire: * * Recalculate the quantum and priority for a thread. */ void thread_quantum_expire( timer_call_param_t p0, timer_call_param_t p1) { register processor_t myprocessor = p0; register thread_t thread = p1; spl_t s; s = splsched(); thread_lock(thread); /* * Check for fail-safe trip. */ if (!(thread->sched_mode & TH_MODE_TIMESHARE)) { extern uint64_t max_unsafe_computation; uint64_t new_computation; new_computation = myprocessor->quantum_end; new_computation -= thread->computation_epoch; if (new_computation + thread->computation_metered > max_unsafe_computation) { extern uint32_t sched_safe_duration; if (thread->sched_mode & TH_MODE_REALTIME) { thread->priority = DEPRESSPRI; thread->safe_mode |= TH_MODE_REALTIME; thread->sched_mode &= ~TH_MODE_REALTIME; } thread->safe_release = sched_tick + sched_safe_duration; thread->sched_mode |= (TH_MODE_FAILSAFE|TH_MODE_TIMESHARE); thread->sched_mode &= ~TH_MODE_PREEMPT; } } /* * Recompute scheduled priority if appropriate. */ if (thread->sched_stamp != sched_tick) update_priority(thread); else if (thread->sched_mode & TH_MODE_TIMESHARE) { thread_timer_delta(thread); thread->sched_usage += thread->sched_delta; thread->sched_delta = 0; /* * Adjust the scheduled priority if * the thread has not been promoted * and is not depressed. */ if ( !(thread->sched_mode & TH_MODE_PROMOTED) && !(thread->sched_mode & TH_MODE_ISDEPRESSED) ) compute_my_priority(thread); } /* * This quantum is up, give this thread another. */ if (first_quantum(myprocessor)) myprocessor->slice_quanta--; thread->current_quantum = (thread->sched_mode & TH_MODE_REALTIME)? thread->realtime.computation: std_quantum; myprocessor->quantum_end += thread->current_quantum; timer_call_enter1(&myprocessor->quantum_timer, thread, myprocessor->quantum_end); thread_unlock(thread); /* * Check for and schedule ast if needed. */ ast_check(myprocessor); splx(s); }