/* * 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 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. */ /* */ /* * kern/ast.h: Definitions for Asynchronous System Traps. */ #ifndef _KERN_AST_H_ #define _KERN_AST_H_ #include <cpus.h> #include <platforms.h> #include <kern/assert.h> #include <kern/cpu_number.h> #include <kern/macro_help.h> #include <kern/lock.h> #include <kern/spl.h> #include <machine/ast.h> /* * A CPU takes an AST when it is about to return to user code. * Instead of going back to user code, it calls ast_taken. * Machine-dependent code is responsible for maintaining * a set of reasons for an AST, and passing this set to ast_taken. */ typedef unsigned int ast_t; /* * Bits for reasons */ #define AST_HALT 0x01 #define AST_TERMINATE 0x02 #define AST_BLOCK 0x04 #define AST_QUANTUM 0x08 #define AST_URGENT 0x10 #define AST_APC 0x20 /* migration APC hook */ /* * JMM - This is here temporarily. AST_BSD is used to simulate a * general purpose mechanism for setting asynchronous procedure calls * from the outside. */ #define AST_BSD 0x80 #define AST_BSD_INIT 0x100 #define AST_NONE 0x00 #define AST_ALL (~AST_NONE) #define AST_SCHEDULING (AST_HALT | AST_TERMINATE | AST_BLOCK) #define AST_PREEMPT (AST_BLOCK | AST_QUANTUM | AST_URGENT) extern volatile ast_t need_ast[NCPUS]; #ifdef MACHINE_AST /* * machine/ast.h is responsible for defining aston and astoff. */ #else /* MACHINE_AST */ #define aston(mycpu) #define astoff(mycpu) #endif /* MACHINE_AST */ /* Initialize module */ extern void ast_init(void); /* Handle ASTs */ extern void ast_taken( ast_t mask, boolean_t enable); /* Check for pending ASTs */ extern void ast_check(void); /* * Per-thread ASTs are reset at context-switch time. */ #ifndef MACHINE_AST_PER_THREAD #define MACHINE_AST_PER_THREAD 0 #endif #define AST_PER_THREAD ( AST_HALT | AST_TERMINATE | AST_APC | AST_BSD | \ MACHINE_AST_PER_THREAD ) /* * ast_needed(), ast_on(), ast_off(), ast_context(), and ast_propagate() * assume splsched. */ #define ast_needed(mycpu) need_ast[mycpu] #define ast_on_fast(reasons) \ MACRO_BEGIN \ int mycpu = cpu_number(); \ if ((need_ast[mycpu] |= (reasons)) != AST_NONE) \ { aston(mycpu); } \ MACRO_END #define ast_off_fast(reasons) \ MACRO_BEGIN \ int mycpu = cpu_number(); \ if ((need_ast[mycpu] &= ~(reasons)) == AST_NONE) \ { astoff(mycpu); } \ MACRO_END #define ast_propagate(reasons) ast_on(reasons) #define ast_context(act, mycpu) \ MACRO_BEGIN \ assert((mycpu) == cpu_number()); \ if ((need_ast[mycpu] = \ ((need_ast[mycpu] &~ AST_PER_THREAD) | (act)->ast)) != AST_NONE) \ { aston(mycpu); } \ else \ { astoff(mycpu); } \ MACRO_END #define ast_on(reason) ast_on_fast(reason) #define ast_off(reason) ast_off_fast(reason) #define thread_ast_set(act, reason) ((act)->ast |= (reason)) #define thread_ast_clear(act, reason) ((act)->ast &= ~(reason)) #define thread_ast_clear_all(act) ((act)->ast = AST_NONE) /* * NOTE: if thread is the current thread, thread_ast_set() should * be followed by ast_propagate(). */ #ifdef MACH_KERNEL_PRIVATE #define ast_urgency() (need_ast[cpu_number()] & AST_URGENT) #endif /* MACH_KERNEL_PRIVATE */ #endif /* _KERN_AST_H_ */