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

/*
 * 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_ */
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
	11	*
	12	* This Original Code and all software distributed under the License are
	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	/*
	23	* @OSF_COPYRIGHT@
	24	*/
	25	/*
	26	* Mach Operating System
	27	* Copyright (c) 1991,1990,1989 Carnegie Mellon University
	28	* All Rights Reserved.
	29	*
	30	* Permission to use, copy, modify and distribute this software and its
	31	* documentation is hereby granted, provided that both the copyright
	32	* notice and this permission notice appear in all copies of the
	33	* software, derivative works or modified versions, and any portions
	34	* thereof, and that both notices appear in supporting documentation.
	35	*
	36	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	37	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	38	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	39	*
	40	* Carnegie Mellon requests users of this software to return to
	41	*
	42	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	43	* School of Computer Science
	44	* Carnegie Mellon University
	45	* Pittsburgh PA 15213-3890
	46	*
	47	* any improvements or extensions that they make and grant Carnegie Mellon
	48	* the rights to redistribute these changes.
	49	*/
	50	/*
	51	*/
	52
	53	/*
	54	* kern/ast.h: Definitions for Asynchronous System Traps.
	55	*/
	56
	57	#ifndef _KERN_AST_H_
	58	#define _KERN_AST_H_
	59
	60	#include <cpus.h>
	61	#include <platforms.h>
	62
	63	#include <kern/assert.h>
	64	#include <kern/cpu_number.h>
65	#include <kern/macro_help.h>
66	#include <kern/lock.h>
67	#include <kern/spl.h>
68	#include <machine/ast.h>
69
70	/*
71	* A CPU takes an AST when it is about to return to user code.
72	* Instead of going back to user code, it calls ast_taken.
73	* Machine-dependent code is responsible for maintaining
74	* a set of reasons for an AST, and passing this set to ast_taken.
75	*/
0b4e3aa0	76	typedef unsigned int ast_t;
1c79356b A	77
	78	/*
	79	* Bits for reasons
	80	*/
0b4e3aa0	81	#define AST_HALT 0x01
1c79356b A	82	#define AST_TERMINATE 0x02
1c79356b A	83	#define AST_BLOCK 0x04
0b4e3aa0 A	84	#define AST_QUANTUM 0x08
	85	#define AST_URGENT 0x10
	86	#define AST_APC 0x20 /* migration APC hook */
1c79356b A	87	/*
	88	* JMM - This is here temporarily. AST_BSD is used to simulate a
	89	* general purpose mechanism for setting asynchronous procedure calls
	90	* from the outside.
	91	*/
0b4e3aa0	92	#define AST_BSD 0x80
1c79356b A	93	#define AST_BSD_INIT 0x100
1c79356b A	94
0b4e3aa0 A	95	#define AST_NONE 0x00
0b4e3aa0 A	96	#define AST_ALL (~AST_NONE)
1c79356b	97
0b4e3aa0 A	98	#define AST_SCHEDULING (AST_HALT \| AST_TERMINATE \| AST_BLOCK)
0b4e3aa0 A	99	#define AST_PREEMPT (AST_BLOCK \| AST_QUANTUM \| AST_URGENT)
1c79356b	100
0b4e3aa0	101	extern volatile ast_t need_ast[NCPUS];
1c79356b A	102
	103	#ifdef MACHINE_AST
	104	/*
	105	* machine/ast.h is responsible for defining aston and astoff.
	106	*/
	107	#else /* MACHINE_AST */
	108
	109	#define aston(mycpu)
	110	#define astoff(mycpu)
	111
	112	#endif /* MACHINE_AST */
	113
	114	/* Initialize module */
0b4e3aa0	115	extern void ast_init(void);
1c79356b A	116
1c79356b A	117	/* Handle ASTs */
0b4e3aa0 A	118	extern void ast_taken(
	119	ast_t mask,
	120	boolean_t enable);
1c79356b A	121
	122	/* Check for pending ASTs */
	123	extern void ast_check(void);
	124
	125	/*
	126	* Per-thread ASTs are reset at context-switch time.
	127	*/
	128	#ifndef MACHINE_AST_PER_THREAD
	129	#define MACHINE_AST_PER_THREAD 0
	130	#endif
	131
0b4e3aa0 A	132	#define AST_PER_THREAD ( AST_HALT \| AST_TERMINATE \| AST_APC \| AST_BSD \| \
0b4e3aa0 A	133	MACHINE_AST_PER_THREAD )
1c79356b	134	/*
0b4e3aa0 A	135	* ast_needed(), ast_on(), ast_off(), ast_context(), and ast_propagate()
0b4e3aa0 A	136	* assume splsched.
1c79356b	137	*/
0b4e3aa0	138	#define ast_needed(mycpu) need_ast[mycpu]
1c79356b	139
0b4e3aa0 A	140	#define ast_on_fast(reasons) \
	141	MACRO_BEGIN \
	142	int mycpu = cpu_number(); \
	143	if ((need_ast[mycpu] \|= (reasons)) != AST_NONE) \
	144	{ aston(mycpu); } \
1c79356b A	145	MACRO_END
1c79356b A	146
0b4e3aa0 A	147	#define ast_off_fast(reasons) \
	148	MACRO_BEGIN \
	149	int mycpu = cpu_number(); \
	150	if ((need_ast[mycpu] &= ~(reasons)) == AST_NONE) \
	151	{ astoff(mycpu); } \
1c79356b A	152	MACRO_END
	153
	154	#define ast_propagate(reasons) ast_on(reasons)
	155
0b4e3aa0 A	156	#define ast_context(act, mycpu) \
	157	MACRO_BEGIN \
	158	assert((mycpu) == cpu_number()); \
	159	if ((need_ast[mycpu] = \
	160	((need_ast[mycpu] &~ AST_PER_THREAD) \| (act)->ast)) != AST_NONE) \
	161	{ aston(mycpu); } \
	162	else \
	163	{ astoff(mycpu); } \
1c79356b A	164	MACRO_END
	165
	166	#define ast_on(reason) ast_on_fast(reason)
	167	#define ast_off(reason) ast_off_fast(reason)
	168
0b4e3aa0 A	169	#define thread_ast_set(act, reason) ((act)->ast \|= (reason))
	170	#define thread_ast_clear(act, reason) ((act)->ast &= ~(reason))
	171	#define thread_ast_clear_all(act) ((act)->ast = AST_NONE)
1c79356b A	172
1c79356b A	173	/*
0b4e3aa0 A	174	* NOTE: if thread is the current thread, thread_ast_set() should
0b4e3aa0 A	175	* be followed by ast_propagate().
1c79356b A	176	*/
	177
	178	#ifdef MACH_KERNEL_PRIVATE
	179
0b4e3aa0	180	#define ast_urgency() (need_ast[cpu_number()] & AST_URGENT)
1c79356b A	181
	182	#endif /* MACH_KERNEL_PRIVATE */
	183
	184	#endif /* _KERN_AST_H_ */