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

/*
 * Copyright (c) 2000-2005 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:	zalloc.h
 *	Author:	Avadis Tevanian, Jr.
 *	Date:	 1985
 *
 */

#ifdef	KERNEL_PRIVATE

#ifndef	_KERN_ZALLOC_H_
#define _KERN_ZALLOC_H_

#include <mach/machine/vm_types.h>
#include <kern/kern_types.h>
#include <sys/cdefs.h>

#ifdef	MACH_KERNEL_PRIVATE

#include <zone_debug.h>
#include <mach_kdb.h>
#include <kern/lock.h>
#include <kern/locks.h>
#include <kern/queue.h>
#include <kern/call_entry.h>

/*
 *	A zone is a collection of fixed size blocks for which there
 *	is fast allocation/deallocation access.  Kernel routines can
 *	use zones to manage data structures dynamically, creating a zone
 *	for each type of data structure to be managed.
 *
 */

struct zone {
	int		count;		/* Number of elements used now */
	vm_offset_t	free_elements;
	decl_lck_mtx_data(,lock)	/* zone lock */
	lck_mtx_ext_t   lock_ext;	/* placeholder for indirect mutex */
	lck_attr_t      lock_attr;	/* zone lock attribute */
	lck_grp_t       lock_grp;	/* zone lock group */
	lck_grp_attr_t  lock_grp_attr;	/* zone lock group attribute */
	vm_size_t	cur_size;	/* current memory utilization */
	vm_size_t	max_size;	/* how large can this zone grow */
	vm_size_t	elem_size;	/* size of an element */
	vm_size_t	alloc_size;	/* size used for more memory */
	uint64_t	sum_count;	/* count of allocs (life of zone) */
	unsigned int
	/* boolean_t */ exhaustible :1,	/* (F) merely return if empty? */
	/* boolean_t */	collectable :1,	/* (F) garbage collect empty pages */
	/* boolean_t */	expandable :1,	/* (T) expand zone (with message)? */
	/* boolean_t */ allows_foreign :1,/* (F) allow non-zalloc space */
	/* boolean_t */	doing_alloc :1,	/* is zone expanding now? */
	/* boolean_t */	waiting :1,	/* is thread waiting for expansion? */
	/* boolean_t */	async_pending :1,	/* asynchronous allocation pending? */
#if CONFIG_ZLEAKS
	/* boolean_t */ zleak_on :1,	/* Are we collecting allocation information? */
#endif	/* ZONE_DEBUG */
	/* boolean_t */	caller_acct: 1, /* do we account allocation/free to the caller? */  
	/* boolean_t */	doing_gc :1,	/* garbage collect in progress? */
	/* boolean_t */ noencrypt :1,
	/* boolean_t */	no_callout:1,
	/* boolean_t */	async_prio_refill:1;
	int		index;		/* index into zone_info arrays for this zone */
	struct zone *	next_zone;	/* Link for all-zones list */
	call_entry_data_t	call_async_alloc;	/* callout for asynchronous alloc */
	const char	*zone_name;	/* a name for the zone */
#if	ZONE_DEBUG
	queue_head_t	active_zones;	/* active elements */
#endif	/* ZONE_DEBUG */

#if CONFIG_ZLEAKS
	uint32_t num_allocs;	/* alloc stats for zleak benchmarks */
	uint32_t num_frees;		/* free stats for zleak benchmarks */
	uint32_t zleak_capture; /* per-zone counter for capturing every N allocations */
#endif /* CONFIG_ZLEAKS */
	vm_size_t	prio_refill_watermark;
	thread_t	zone_replenish_thread;
};

/*
 *	structure for tracking zone usage
 *	Used either one per task/thread for all zones or <per-task,per-zone>.
 */
typedef struct zinfo_usage_store_t {
	/* These fields may be updated atomically, and so must be 8 byte aligned */
	uint64_t	alloc __attribute__((aligned(8)));		/* allocation counter */
	uint64_t	free __attribute__((aligned(8)));		/* free counter */
} zinfo_usage_store_t;
typedef zinfo_usage_store_t *zinfo_usage_t;

extern void		zone_gc(void);
extern void		consider_zone_gc(boolean_t);

/* Steal memory for zone module */
extern void		zone_steal_memory(void);

/* Bootstrap zone module (create zone zone) */
extern void		zone_bootstrap(void) __attribute__((section("__TEXT, initcode")));

/* Init zone module */
extern void		zone_init(
					vm_size_t	map_size) __attribute__((section("__TEXT, initcode")));

/* Handle per-task zone info */
extern void		zinfo_task_init(task_t task);
extern void		zinfo_task_free(task_t task);


/* Stack use statistics */
extern void		stack_fake_zone_init(int zone_index);
extern void		stack_fake_zone_info(
					int			*count, 
					vm_size_t	*cur_size, 
					vm_size_t	*max_size,
					vm_size_t	*elem_size,
					vm_size_t	*alloc_size, 
					uint64_t	*sum_size,
					int			*collectable, 
					int			*exhaustable,
					int		*caller_acct);

#if		ZONE_DEBUG

#if		MACH_KDB

extern void *	next_element(
				zone_t		z,
				void 		*elt);

extern void *	first_element(
				zone_t		z);

#endif	/* MACH_KDB */

extern void		zone_debug_enable(
				zone_t		z);

extern void		zone_debug_disable(
				zone_t		z);

#endif	/* ZONE_DEBUG */

#endif	/* MACH_KERNEL_PRIVATE */

__BEGIN_DECLS

#ifdef	XNU_KERNEL_PRIVATE

/* Allocate from zone */
extern void *	zalloc(
					zone_t		zone);

/* Free zone element */
extern void		zfree(
					zone_t		zone,
					void 		*elem);

/* Create zone */
extern zone_t	zinit(
					vm_size_t	size,		/* the size of an element */
					vm_size_t	maxmem,		/* maximum memory to use */
					vm_size_t	alloc,		/* allocation size */
					const char	*name);		/* a name for the zone */


/* Non-blocking version of zalloc */
extern void *	zalloc_noblock(
					zone_t		zone);

/* direct (non-wrappered) interface */
extern void *	zalloc_canblock(
					zone_t		zone,
					boolean_t	canblock);

/* Get from zone free list */
extern void *	zget(
					zone_t		zone);

/* Fill zone with memory */
extern void		zcram(
					zone_t		zone,
					vm_offset_t	newmem,
					vm_size_t	size);

/* Initially fill zone with specified number of elements */
extern int		zfill(
					zone_t		zone,
					int			nelem);

/* Change zone parameters */
extern void		zone_change(
					zone_t			zone,
					unsigned int	item,
					boolean_t		value);
extern void		zone_prio_refill_configure(zone_t, vm_size_t);
/* Item definitions */
#define Z_EXHAUST	1	/* Make zone exhaustible	*/
#define Z_COLLECT	2	/* Make zone collectable	*/
#define Z_EXPAND	3	/* Make zone expandable		*/
#define	Z_FOREIGN	4	/* Allow collectable zone to contain foreign elements */
#define Z_CALLERACCT	5	/* Account alloc/free against the caller */
#define Z_NOENCRYPT	6	/* Don't encrypt zone during hibernation */
#define Z_NOCALLOUT 	7	/* Don't asynchronously replenish the zone via
				 * callouts
				 */
/* Preallocate space for zone from zone map */
extern void		zprealloc(
					zone_t		zone,
					vm_size_t	size);

extern integer_t	zone_free_count(
						zone_t		zone);

/*
 * MAX_ZTRACE_DEPTH configures how deep of a stack trace is taken on each zalloc in the zone of interest.  15
 * levels is usually enough to get past all the layers of code in kalloc and IOKit and see who the actual
 * caller is up above these lower levels.
 *
 * This is used both for the zone leak detector and the zone corruption log.
 */

#define MAX_ZTRACE_DEPTH	15

/* 
 *  Structure for keeping track of a backtrace, used for leak detection.
 *  This is in the .h file because it is used during panic, see kern/debug.c
 *  A non-zero size indicates that the trace is in use.
 */
struct ztrace {
	vm_size_t		zt_size;			/* How much memory are all the allocations referring to this trace taking up? */
	uint32_t		zt_depth;			/* depth of stack (0 to MAX_ZTRACE_DEPTH) */
	void*			zt_stack[MAX_ZTRACE_DEPTH];	/* series of return addresses from OSBacktrace */
	uint32_t		zt_collisions;			/* How many times did a different stack land here while it was occupied? */
	uint32_t		zt_hit_count;			/* for determining effectiveness of hash function */
};

#if CONFIG_ZLEAKS

/* support for the kern.zleak.* sysctls */

extern kern_return_t zleak_activate(void);
extern vm_size_t zleak_max_zonemap_size;
extern vm_size_t zleak_global_tracking_threshold;
extern vm_size_t zleak_per_zone_tracking_threshold;

extern int get_zleak_state(void);

#endif	/* CONFIG_ZLEAKS */

/* These functions used for leak detection both in zalloc.c and mbuf.c */
extern uint32_t fastbacktrace(uintptr_t* bt, uint32_t max_frames);
extern uintptr_t hash_mix(uintptr_t x);
extern uint32_t hashbacktrace(uintptr_t* bt, uint32_t depth, uint32_t max_size);
extern uint32_t hashaddr(uintptr_t pt, uint32_t max_size);

#endif	/* XNU_KERNEL_PRIVATE */

__END_DECLS

#endif	/* _KERN_ZALLOC_H_ */

#endif	/* KERNEL_PRIVATE */
Commit	Line	Data
1c79356b	1	/*
91447636	2	* Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
1c79356b	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
2d21ac55 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.
8f6c56a5	14	*
2d21ac55 A	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
8f6c56a5 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
8f6c56a5	25	*
2d21ac55	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: zalloc.h
	60	* Author: Avadis Tevanian, Jr.
	61	* Date: 1985
	62	*
	63	*/
	64
91447636 A	65	#ifdef KERNEL_PRIVATE
91447636 A	66
1c79356b A	67	#ifndef _KERN_ZALLOC_H_
	68	#define _KERN_ZALLOC_H_
	69
	70	#include <mach/machine/vm_types.h>
	71	#include <kern/kern_types.h>
91447636	72	#include <sys/cdefs.h>
9bccf70c A	73
	74	#ifdef MACH_KERNEL_PRIVATE
	75
1c79356b A	76	#include <zone_debug.h>
	77	#include <mach_kdb.h>
	78	#include <kern/lock.h>
2d21ac55	79	#include <kern/locks.h>
1c79356b	80	#include <kern/queue.h>
0b4e3aa0	81	#include <kern/call_entry.h>
1c79356b A	82
	83	/*
	84	* A zone is a collection of fixed size blocks for which there
	85	* is fast allocation/deallocation access. Kernel routines can
	86	* use zones to manage data structures dynamically, creating a zone
	87	* for each type of data structure to be managed.
	88	*
	89	*/
	90
	91	struct zone {
	92	int count; /* Number of elements used now */
	93	vm_offset_t free_elements;
2d21ac55 A	94	decl_lck_mtx_data(,lock) /* zone lock */
	95	lck_mtx_ext_t lock_ext; /* placeholder for indirect mutex */
	96	lck_attr_t lock_attr; /* zone lock attribute */
	97	lck_grp_t lock_grp; /* zone lock group */
	98	lck_grp_attr_t lock_grp_attr; /* zone lock group attribute */
1c79356b A	99	vm_size_t cur_size; /* current memory utilization */
	100	vm_size_t max_size; /* how large can this zone grow */
	101	vm_size_t elem_size; /* size of an element */
	102	vm_size_t alloc_size; /* size used for more memory */
6d2010ae	103	uint64_t sum_count; /* count of allocs (life of zone) */
1c79356b A	104	unsigned int
	105	/* boolean_t / exhaustible :1, / (F) merely return if empty? */
	106	/* boolean_t / collectable :1, / (F) garbage collect empty pages */
	107	/* boolean_t / expandable :1, / (T) expand zone (with message)? */
	108	/* boolean_t / allows_foreign :1,/ (F) allow non-zalloc space */
	109	/* boolean_t / doing_alloc :1, / is zone expanding now? */
0b4e3aa0	110	/* boolean_t / waiting :1, / is thread waiting for expansion? */
a3d08fcd	111	/* boolean_t / async_pending :1, / asynchronous allocation pending? */
6d2010ae A	112	#if CONFIG_ZLEAKS
	113	/* boolean_t / zleak_on :1, / Are we collecting allocation information? */
	114	#endif /* ZONE_DEBUG */
	115	/* boolean_t / caller_acct: 1, / do we account allocation/free to the caller? */
0b4c1975	116	/* boolean_t / doing_gc :1, / garbage collect in progress? */
7ddcb079 A	117	/* boolean_t */ noencrypt :1,
	118	/* boolean_t */ no_callout:1,
	119	/* boolean_t */ async_prio_refill:1;
6d2010ae	120	int index; /* index into zone_info arrays for this zone */
1c79356b	121	struct zone * next_zone; /* Link for all-zones list */
0b4e3aa0	122	call_entry_data_t call_async_alloc; /* callout for asynchronous alloc */
91447636	123	const char zone_name; / a name for the zone */
1c79356b A	124	#if ZONE_DEBUG
	125	queue_head_t active_zones; /* active elements */
	126	#endif /* ZONE_DEBUG */
6d2010ae A	127
	128	#if CONFIG_ZLEAKS
	129	uint32_t num_allocs; /* alloc stats for zleak benchmarks */
	130	uint32_t num_frees; /* free stats for zleak benchmarks */
	131	uint32_t zleak_capture; /* per-zone counter for capturing every N allocations */
	132	#endif /* CONFIG_ZLEAKS */
7ddcb079 A	133	vm_size_t prio_refill_watermark;
7ddcb079 A	134	thread_t zone_replenish_thread;
1c79356b A	135	};
1c79356b A	136
6d2010ae A	137	/*
	138	* structure for tracking zone usage
	139	* Used either one per task/thread for all zones or <per-task,per-zone>.
	140	*/
	141	typedef struct zinfo_usage_store_t {
	142	/* These fields may be updated atomically, and so must be 8 byte aligned */
	143	uint64_t alloc __attribute__((aligned(8))); /* allocation counter */
	144	uint64_t free __attribute__((aligned(8))); /* free counter */
	145	} zinfo_usage_store_t;
	146	typedef zinfo_usage_store_t *zinfo_usage_t;
	147
1c79356b	148	extern void zone_gc(void);
b0d623f7	149	extern void consider_zone_gc(boolean_t);
1c79356b A	150
	151	/* Steal memory for zone module */
	152	extern void zone_steal_memory(void);
	153
	154	/* Bootstrap zone module (create zone zone) */
2d21ac55	155	extern void zone_bootstrap(void) __attribute__((section("__TEXT, initcode")));
1c79356b A	156
1c79356b A	157	/* Init zone module */
91447636	158	extern void zone_init(
2d21ac55	159	vm_size_t map_size) __attribute__((section("__TEXT, initcode")));
1c79356b	160
6d2010ae A	161	/* Handle per-task zone info */
	162	extern void zinfo_task_init(task_t task);
	163	extern void zinfo_task_free(task_t task);
	164
	165
91447636	166	/* Stack use statistics */
6d2010ae	167	extern void stack_fake_zone_init(int zone_index);
91447636 A	168	extern void stack_fake_zone_info(
	169	int *count,
	170	vm_size_t *cur_size,
	171	vm_size_t *max_size,
	172	vm_size_t *elem_size,
	173	vm_size_t *alloc_size,
6d2010ae	174	uint64_t *sum_size,
91447636	175	int *collectable,
6d2010ae A	176	int *exhaustable,
6d2010ae A	177	int *caller_acct);
1c79356b	178
91447636	179	#if ZONE_DEBUG
1c79356b	180
91447636	181	#if MACH_KDB
1c79356b	182
91447636 A	183	extern void * next_element(
	184	zone_t z,
	185	void *elt);
1c79356b	186
91447636 A	187	extern void * first_element(
91447636 A	188	zone_t z);
1c79356b	189
91447636 A	190	#endif /* MACH_KDB */
	191
	192	extern void zone_debug_enable(
	193	zone_t z);
	194
	195	extern void zone_debug_disable(
	196	zone_t z);
	197
	198	#endif /* ZONE_DEBUG */
	199
	200	#endif /* MACH_KERNEL_PRIVATE */
	201
	202	__BEGIN_DECLS
	203
	204	#ifdef XNU_KERNEL_PRIVATE
	205
	206	/* Allocate from zone */
	207	extern void * zalloc(
	208	zone_t zone);
1c79356b A	209
	210	/* Free zone element */
	211	extern void zfree(
91447636 A	212	zone_t zone,
	213	void *elem);
	214
	215	/* Create zone */
	216	extern zone_t zinit(
	217	vm_size_t size, /* the size of an element */
	218	vm_size_t maxmem, /* maximum memory to use */
	219	vm_size_t alloc, /* allocation size */
	220	const char name); / a name for the zone */
	221
	222
	223	/* Non-blocking version of zalloc */
	224	extern void * zalloc_noblock(
	225	zone_t zone);
	226
	227	/* direct (non-wrappered) interface */
	228	extern void * zalloc_canblock(
	229	zone_t zone,
	230	boolean_t canblock);
	231
	232	/* Get from zone free list */
	233	extern void * zget(
	234	zone_t zone);
1c79356b A	235
	236	/* Fill zone with memory */
	237	extern void zcram(
91447636	238	zone_t zone,
7ddcb079	239	vm_offset_t newmem,
91447636	240	vm_size_t size);
1c79356b A	241
	242	/* Initially fill zone with specified number of elements */
	243	extern int zfill(
91447636 A	244	zone_t zone,
	245	int nelem);
	246
1c79356b A	247	/* Change zone parameters */
1c79356b A	248	extern void zone_change(
91447636 A	249	zone_t zone,
	250	unsigned int item,
	251	boolean_t value);
7ddcb079	252	extern void zone_prio_refill_configure(zone_t, vm_size_t);
91447636	253	/* Item definitions */
1c79356b A	254	#define Z_EXHAUST 1 /* Make zone exhaustible */
	255	#define Z_COLLECT 2 /* Make zone collectable */
	256	#define Z_EXPAND 3 /* Make zone expandable */
91447636	257	#define Z_FOREIGN 4 /* Allow collectable zone to contain foreign elements */
6d2010ae	258	#define Z_CALLERACCT 5 /* Account alloc/free against the caller */
0b4c1975	259	#define Z_NOENCRYPT 6 /* Don't encrypt zone during hibernation */
7ddcb079 A	260	#define Z_NOCALLOUT 7 /* Don't asynchronously replenish the zone via
	261	* callouts
	262	*/
91447636 A	263	/* Preallocate space for zone from zone map */
	264	extern void zprealloc(
	265	zone_t zone,
	266	vm_size_t size);
9bccf70c	267
91447636 A	268	extern integer_t zone_free_count(
91447636 A	269	zone_t zone);
9bccf70c	270
6d2010ae A	271	/*
	272	* MAX_ZTRACE_DEPTH configures how deep of a stack trace is taken on each zalloc in the zone of interest. 15
	273	* levels is usually enough to get past all the layers of code in kalloc and IOKit and see who the actual
	274	* caller is up above these lower levels.
	275	*
	276	* This is used both for the zone leak detector and the zone corruption log.
	277	*/
	278
	279	#define MAX_ZTRACE_DEPTH 15
	280
	281	/*
	282	* Structure for keeping track of a backtrace, used for leak detection.
	283	* This is in the .h file because it is used during panic, see kern/debug.c
	284	* A non-zero size indicates that the trace is in use.
	285	*/
	286	struct ztrace {
	287	vm_size_t zt_size; /* How much memory are all the allocations referring to this trace taking up? */
	288	uint32_t zt_depth; /* depth of stack (0 to MAX_ZTRACE_DEPTH) */
	289	void* zt_stack[MAX_ZTRACE_DEPTH]; /* series of return addresses from OSBacktrace */
	290	uint32_t zt_collisions; /* How many times did a different stack land here while it was occupied? */
	291	uint32_t zt_hit_count; /* for determining effectiveness of hash function */
	292	};
	293
	294	#if CONFIG_ZLEAKS
	295
	296	/* support for the kern.zleak.* sysctls */
	297
	298	extern kern_return_t zleak_activate(void);
	299	extern vm_size_t zleak_max_zonemap_size;
	300	extern vm_size_t zleak_global_tracking_threshold;
	301	extern vm_size_t zleak_per_zone_tracking_threshold;
	302
	303	extern int get_zleak_state(void);
	304
	305	#endif /* CONFIG_ZLEAKS */
	306
	307	/* These functions used for leak detection both in zalloc.c and mbuf.c */
	308	extern uint32_t fastbacktrace(uintptr_t* bt, uint32_t max_frames);
	309	extern uintptr_t hash_mix(uintptr_t x);
	310	extern uint32_t hashbacktrace(uintptr_t* bt, uint32_t depth, uint32_t max_size);
	311	extern uint32_t hashaddr(uintptr_t pt, uint32_t max_size);
	312
91447636	313	#endif /* XNU_KERNEL_PRIVATE */
9bccf70c	314
91447636	315	__END_DECLS
1c79356b A	316
1c79356b A	317	#endif /* _KERN_ZALLOC_H_ */
91447636 A	318
91447636 A	319	#endif /* KERNEL_PRIVATE */