1 /*	$OpenBSD: pool.h,v 1.18 2004/07/29 09:18:17 mickey Exp $	*/
2 /*	$NetBSD: pool.h,v 1.27 2001/06/06 22:00:17 rafal Exp $	*/
3 
4 /*-
5  * Copyright (c) 1997, 1998, 1999, 2000 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Paul Kranenburg; by Jason R. Thorpe of the Numerical Aerospace
10  * Simulation Facility, NASA Ames Research Center.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the NetBSD
23  *	Foundation, Inc. and its contributors.
24  * 4. Neither the name of The NetBSD Foundation nor the names of its
25  *    contributors may be used to endorse or promote products derived
26  *    from this software without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
29  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
30  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
31  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
32  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
33  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
34  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
35  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
36  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
37  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38  * POSSIBILITY OF SUCH DAMAGE.
39  */
40 
41 #ifndef _SYS_POOL_H_
42 #define _SYS_POOL_H_
43 
44 /*
45  * sysctls.
46  * kern.pool.npools
47  * kern.pool.name.<number>
48  * kern.pool.pool.<number>
49  */
50 #define KERN_POOL_NPOOLS	1
51 #define KERN_POOL_NAME		2
52 #define KERN_POOL_POOL		3
53 
54 #include <sys/lock.h>
55 #include <sys/queue.h>
56 #include <sys/time.h>
57 #include <sys/tree.h>
58 
59 struct pool_cache {
60 	TAILQ_ENTRY(pool_cache)
61 			pc_poollist;	/* entry on pool's group list */
62 	TAILQ_HEAD(, pool_cache_group)
63 			pc_grouplist;	/* Cache group list */
64 	struct pool_cache_group
65 			*pc_allocfrom;	/* group to allocate from */
66 	struct pool_cache_group
67 			*pc_freeto;	/* grop to free to */
68 	struct pool	*pc_pool;	/* parent pool */
69 	struct simplelock pc_slock;	/* mutex */
70 
71 	int		(*pc_ctor)(void *, void *, int);
72 	void		(*pc_dtor)(void *, void *);
73 	void		*pc_arg;
74 
75 	/* Statistics. */
76 	unsigned long	pc_hits;	/* cache hits */
77 	unsigned long	pc_misses;	/* cache misses */
78 
79 	unsigned long	pc_ngroups;	/* # cache groups */
80 
81 	unsigned long	pc_nitems;	/* # objects currently in cache */
82 };
83 
84 struct pool_allocator {
85 	void *(*pa_alloc)(struct pool *, int);
86 	void (*pa_free)(struct pool *, void *);
87 	int pa_pagesz;
88 
89 	/* The following fields are for internal use only */
90 	struct simplelock pa_slock;
91 	TAILQ_HEAD(,pool) pa_list;
92 	int pa_flags;
93 #define PA_INITIALIZED	0x01
94 #define PA_WANT	0x02			/* wakeup any sleeping pools on free */
95 	int pa_pagemask;
96 	int pa_pageshift;
97 };
98 
99 LIST_HEAD(pool_pagelist,pool_item_header);
100 
101 struct pool {
102 	TAILQ_ENTRY(pool)
103 			pr_poollist;
104 	struct pool_pagelist
105 			pr_emptypages;	/* Empty pages */
106 	struct pool_pagelist
107 			pr_fullpages;	/* Full pages */
108 	struct pool_pagelist
109 			pr_partpages;	/* Partially-allocated pages */
110 	struct pool_item_header	*pr_curpage;
111 	TAILQ_HEAD(,pool_cache)
112 			pr_cachelist;	/* Caches for this pool */
113 	unsigned int	pr_size;	/* Size of item */
114 	unsigned int	pr_align;	/* Requested alignment, must be 2^n */
115 	unsigned int	pr_itemoffset;	/* Align this offset in item */
116 	unsigned int	pr_minitems;	/* minimum # of items to keep */
117 	unsigned int	pr_minpages;	/* same in page units */
118 	unsigned int	pr_maxpages;	/* maximum # of idle pages to keep */
119 	unsigned int	pr_npages;	/* # of pages allocated */
120 	unsigned int	pr_itemsperpage;/* # items that fit in a page */
121 	unsigned int	pr_slack;	/* unused space in a page */
122 	unsigned int	pr_nitems;	/* number of available items in pool */
123 	unsigned int	pr_nout;	/* # items currently allocated */
124 	unsigned int	pr_hardlimit;	/* hard limit to number of allocated
125 					   items */
126 	unsigned int	pr_serial;	/* unique serial number of the pool */
127 	struct pool_allocator *pr_alloc;/* backend allocator */
128 	TAILQ_ENTRY(pool) pr_alloc_list;/* list of pools using this allocator */
129 	const char	*pr_wchan;	/* tsleep(9) identifier */
130 	unsigned int	pr_flags;	/* r/w flags */
131 	unsigned int	pr_roflags;	/* r/o flags */
132 #define PR_MALLOCOK	0x01
133 #define	PR_NOWAIT	0x00		/* for symmetry */
134 #define PR_WAITOK	0x02
135 #define PR_WANTED	0x04
136 #define PR_PHINPAGE	0x08
137 #define PR_LOGGING	0x10
138 #define PR_LIMITFAIL	0x20	/* even if waiting, fail if we hit limit */
139 #define PR_DEBUG	0x40
140 
141 	/*
142 	 * `pr_slock' protects the pool's data structures when removing
143 	 * items from or returning items to the pool, or when reading
144 	 * or updating read/write fields in the pool descriptor.
145 	 *
146 	 * We assume back-end page allocators provide their own locking
147 	 * scheme.  They will be called with the pool descriptor _unlocked_,
148 	 * since the page allocators may block.
149 	 */
150 	struct simplelock	pr_slock;
151 
152 	SPLAY_HEAD(phtree, pool_item_header) pr_phtree;
153 
154 	int		pr_maxcolor;	/* Cache colouring */
155 	int		pr_curcolor;
156 	int		pr_phoffset;	/* Offset in page of page header */
157 
158 	/*
159 	 * Warning message to be issued, and a per-time-delta rate cap,
160 	 * if the hard limit is reached.
161 	 */
162 	const char	*pr_hardlimit_warning;
163 	struct timeval	pr_hardlimit_ratecap;
164 	struct timeval	pr_hardlimit_warning_last;
165 
166 	/*
167 	 * Instrumentation
168 	 */
169 	unsigned long	pr_nget;	/* # of successful requests */
170 	unsigned long	pr_nfail;	/* # of unsuccessful requests */
171 	unsigned long	pr_nput;	/* # of releases */
172 	unsigned long	pr_npagealloc;	/* # of pages allocated */
173 	unsigned long	pr_npagefree;	/* # of pages released */
174 	unsigned int	pr_hiwat;	/* max # of pages in pool */
175 	unsigned long	pr_nidle;	/* # of idle pages */
176 
177 	/*
178 	 * Diagnostic aides.
179 	 */
180 	struct pool_log	*pr_log;
181 	int		pr_curlogentry;
182 	int		pr_logsize;
183 
184 	const char	*pr_entered_file; /* reentrancy check */
185 	long		pr_entered_line;
186 	void		(*pr_drain_hook)(void *, int);
187 	void		*pr_drain_hook_arg;
188 };
189 
190 #ifdef _KERNEL
191 /* old nointr allocator, still needed for large allocations */
192 extern struct pool_allocator pool_allocator_oldnointr;
193 /* interrupt safe (name preserved for compat) new default allocator */
194 extern struct pool_allocator pool_allocator_nointr;
195 /* previous interrupt safe allocator, allocates from kmem */
196 extern struct pool_allocator pool_allocator_kmem;
197 
198 int		pool_allocator_drain(struct pool_allocator *, struct pool *,
199 		    int);
200 
201 void		pool_init(struct pool *, size_t, u_int, u_int, int,
202 		    const char *, struct pool_allocator *);
203 void		pool_destroy(struct pool *);
204 
205 void		pool_set_drain_hook(struct pool *, void (*)(void *, int),
206 		    void *);
207 
208 void		*pool_get(struct pool *, int);
209 void		pool_put(struct pool *, void *);
210 int		pool_reclaim(struct pool *);
211 
212 #ifdef POOL_DIAGNOSTIC
213 /*
214  * These versions do reentrancy checking.
215  */
216 void		*_pool_get(struct pool *, int, const char *, long);
217 void		_pool_put(struct pool *, void *, const char *, long);
218 int		_pool_reclaim(struct pool *, const char *, long);
219 #define		pool_get(h, f)	_pool_get((h), (f), __FILE__, __LINE__)
220 #define		pool_put(h, v)	_pool_put((h), (v), __FILE__, __LINE__)
221 #define		pool_reclaim(h)	_pool_reclaim((h), __FILE__, __LINE__)
222 #endif /* POOL_DIAGNOSTIC */
223 
224 int		pool_prime(struct pool *, int);
225 void		pool_setlowat(struct pool *, int);
226 void		pool_sethiwat(struct pool *, int);
227 int		pool_sethardlimit(struct pool *, unsigned, const char *, int);
228 void		pool_drain(void *);
229 
230 #ifdef DDB
231 /*
232  * Debugging and diagnostic aides.
233  */
234 void		pool_printit(struct pool *, const char *,
235 		    int (*)(const char *, ...));
236 int		pool_chk(struct pool *, const char *);
237 #endif
238 
239 /*
240  * Pool cache routines.
241  */
242 void		pool_cache_init(struct pool_cache *, struct pool *,
243 		    int (*ctor)(void *, void *, int),
244 		    void (*dtor)(void *, void *),
245 		    void *);
246 void		pool_cache_destroy(struct pool_cache *);
247 void		*pool_cache_get(struct pool_cache *, int);
248 void		pool_cache_put(struct pool_cache *, void *);
249 void		pool_cache_destruct_object(struct pool_cache *, void *);
250 void		pool_cache_invalidate(struct pool_cache *);
251 #endif /* _KERNEL */
252 
253 #endif /* _SYS_POOL_H_ */
254