1/*-
2 * Copyright (c) 2004, 2005,
3 * Bosko Milekic <bmilekic@FreeBSD.org>. All rights reserved.
4 * Copyright (c) 2002, 2003, 2004, 2005,
5 * Jeffrey Roberson <jeff@FreeBSD.org>. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice unmodified, this list of conditions, and the following
12 * disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
| 1/*-
2 * Copyright (c) 2004, 2005,
3 * Bosko Milekic <bmilekic@FreeBSD.org>. All rights reserved.
4 * Copyright (c) 2002, 2003, 2004, 2005,
5 * Jeffrey Roberson <jeff@FreeBSD.org>. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice unmodified, this list of conditions, and the following
12 * disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
|
28 * $FreeBSD: head/sys/vm/uma_int.h 147995 2005-07-14 16:17:21Z rwatson $
| 28 * $FreeBSD: head/sys/vm/uma_int.h 147996 2005-07-14 16:35:13Z rwatson $
|
29 *
30 */
31
32/*
33 * This file includes definitions, structures, prototypes, and inlines that
34 * should not be used outside of the actual implementation of UMA.
35 */
36
37/*
38 * Here's a quick description of the relationship between the objects:
39 *
40 * Kegs contain lists of slabs which are stored in either the full bin, empty
41 * bin, or partially allocated bin, to reduce fragmentation. They also contain
42 * the user supplied value for size, which is adjusted for alignment purposes
43 * and rsize is the result of that. The Keg also stores information for
44 * managing a hash of page addresses that maps pages to uma_slab_t structures
45 * for pages that don't have embedded uma_slab_t's.
46 *
47 * The uma_slab_t may be embedded in a UMA_SLAB_SIZE chunk of memory or it may
48 * be allocated off the page from a special slab zone. The free list within a
49 * slab is managed with a linked list of indexes, which are 8 bit values. If
50 * UMA_SLAB_SIZE is defined to be too large I will have to switch to 16bit
51 * values. Currently on alpha you can get 250 or so 32 byte items and on x86
52 * you can get 250 or so 16byte items. For item sizes that would yield more
53 * than 10% memory waste we potentially allocate a separate uma_slab_t if this
54 * will improve the number of items per slab that will fit.
55 *
56 * Other potential space optimizations are storing the 8bit of linkage in space
57 * wasted between items due to alignment problems. This may yield a much better
58 * memory footprint for certain sizes of objects. Another alternative is to
59 * increase the UMA_SLAB_SIZE, or allow for dynamic slab sizes. I prefer
60 * dynamic slab sizes because we could stick with 8 bit indexes and only use
61 * large slab sizes for zones with a lot of waste per slab. This may create
62 * ineffeciencies in the vm subsystem due to fragmentation in the address space.
63 *
64 * The only really gross cases, with regards to memory waste, are for those
65 * items that are just over half the page size. You can get nearly 50% waste,
66 * so you fall back to the memory footprint of the power of two allocator. I
67 * have looked at memory allocation sizes on many of the machines available to
68 * me, and there does not seem to be an abundance of allocations at this range
69 * so at this time it may not make sense to optimize for it. This can, of
70 * course, be solved with dynamic slab sizes.
71 *
72 * Kegs may serve multiple Zones but by far most of the time they only serve
73 * one. When a Zone is created, a Keg is allocated and setup for it. While
74 * the backing Keg stores slabs, the Zone caches Buckets of items allocated
75 * from the slabs. Each Zone is equipped with an init/fini and ctor/dtor
76 * pair, as well as with its own set of small per-CPU caches, layered above
77 * the Zone's general Bucket cache.
78 *
79 * The PCPU caches are protected by their own locks, while the Zones backed
80 * by the same Keg all share a common Keg lock (to coalesce contention on
81 * the backing slabs). The backing Keg typically only serves one Zone but
82 * in the case of multiple Zones, one of the Zones is considered the
83 * Master Zone and all Zone-related stats from the Keg are done in the
84 * Master Zone. For an example of a Multi-Zone setup, refer to the
85 * Mbuf allocation code.
86 */
87
88/*
89 * This is the representation for normal (Non OFFPAGE slab)
90 *
91 * i == item
92 * s == slab pointer
93 *
94 * <---------------- Page (UMA_SLAB_SIZE) ------------------>
95 * ___________________________________________________________
96 * | _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___________ |
97 * ||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i| |slab header||
98 * ||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_| |___________||
99 * |___________________________________________________________|
100 *
101 *
102 * This is an OFFPAGE slab. These can be larger than UMA_SLAB_SIZE.
103 *
104 * ___________________________________________________________
105 * | _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ |
106 * ||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i| |
107 * ||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_| |
108 * |___________________________________________________________|
109 * ___________ ^
110 * |slab header| |
111 * |___________|---*
112 *
113 */
114
115#ifndef VM_UMA_INT_H
116#define VM_UMA_INT_H
117
118#define UMA_SLAB_SIZE PAGE_SIZE /* How big are our slabs? */
119#define UMA_SLAB_MASK (PAGE_SIZE - 1) /* Mask to get back to the page */
120#define UMA_SLAB_SHIFT PAGE_SHIFT /* Number of bits PAGE_MASK */
121
122#define UMA_BOOT_PAGES 48 /* Pages allocated for startup */
123
124/* Max waste before going to off page slab management */
125#define UMA_MAX_WASTE (UMA_SLAB_SIZE / 10)
126
127/*
128 * I doubt there will be many cases where this is exceeded. This is the initial
129 * size of the hash table for uma_slabs that are managed off page. This hash
130 * does expand by powers of two. Currently it doesn't get smaller.
131 */
132#define UMA_HASH_SIZE_INIT 32
133
134/*
135 * I should investigate other hashing algorithms. This should yield a low
136 * number of collisions if the pages are relatively contiguous.
137 *
138 * This is the same algorithm that most processor caches use.
139 *
140 * I'm shifting and masking instead of % because it should be faster.
141 */
142
143#define UMA_HASH(h, s) ((((unsigned long)s) >> UMA_SLAB_SHIFT) & \
144 (h)->uh_hashmask)
145
146#define UMA_HASH_INSERT(h, s, mem) \
147 SLIST_INSERT_HEAD(&(h)->uh_slab_hash[UMA_HASH((h), \
148 (mem))], (s), us_hlink);
149#define UMA_HASH_REMOVE(h, s, mem) \
150 SLIST_REMOVE(&(h)->uh_slab_hash[UMA_HASH((h), \
151 (mem))], (s), uma_slab, us_hlink);
152
153/* Hash table for freed address -> slab translation */
154
155SLIST_HEAD(slabhead, uma_slab);
156
157struct uma_hash {
158 struct slabhead *uh_slab_hash; /* Hash table for slabs */
159 int uh_hashsize; /* Current size of the hash table */
160 int uh_hashmask; /* Mask used during hashing */
161};
162
163/*
164 * Structures for per cpu queues.
165 */
166
167struct uma_bucket {
168 LIST_ENTRY(uma_bucket) ub_link; /* Link into the zone */
169 int16_t ub_cnt; /* Count of free items. */
170 int16_t ub_entries; /* Max items. */
171 void *ub_bucket[]; /* actual allocation storage */
172};
173
174typedef struct uma_bucket * uma_bucket_t;
175
176struct uma_cache {
177 uma_bucket_t uc_freebucket; /* Bucket we're freeing to */
178 uma_bucket_t uc_allocbucket; /* Bucket to allocate from */
179 u_int64_t uc_allocs; /* Count of allocations */
180 u_int64_t uc_frees; /* Count of frees */
181};
182
183typedef struct uma_cache * uma_cache_t;
184
185/*
186 * Keg management structure
187 *
188 * TODO: Optimize for cache line size
189 *
190 */
191struct uma_keg {
192 LIST_ENTRY(uma_keg) uk_link; /* List of all kegs */
193
194 struct mtx uk_lock; /* Lock for the keg */
195 struct uma_hash uk_hash;
196
197 LIST_HEAD(,uma_zone) uk_zones; /* Keg's zones */
198 LIST_HEAD(,uma_slab) uk_part_slab; /* partially allocated slabs */
199 LIST_HEAD(,uma_slab) uk_free_slab; /* empty slab list */
200 LIST_HEAD(,uma_slab) uk_full_slab; /* full slabs */
201
202 u_int32_t uk_recurse; /* Allocation recursion count */
203 u_int32_t uk_align; /* Alignment mask */
204 u_int32_t uk_pages; /* Total page count */
205 u_int32_t uk_free; /* Count of items free in slabs */
206 u_int32_t uk_size; /* Requested size of each item */
207 u_int32_t uk_rsize; /* Real size of each item */
208 u_int32_t uk_maxpages; /* Maximum number of pages to alloc */
209
210 uma_init uk_init; /* Keg's init routine */
211 uma_fini uk_fini; /* Keg's fini routine */
212 uma_alloc uk_allocf; /* Allocation function */
213 uma_free uk_freef; /* Free routine */
214
215 struct vm_object *uk_obj; /* Zone specific object */
216 vm_offset_t uk_kva; /* Base kva for zones with objs */
217 uma_zone_t uk_slabzone; /* Slab zone backing us, if OFFPAGE */
218
219 u_int16_t uk_pgoff; /* Offset to uma_slab struct */
220 u_int16_t uk_ppera; /* pages per allocation from backend */
221 u_int16_t uk_ipers; /* Items per slab */
222 u_int16_t uk_flags; /* Internal flags */
223};
224
225/* Simpler reference to uma_keg for internal use. */
226typedef struct uma_keg * uma_keg_t;
227
228/* Page management structure */
229
230/* Sorry for the union, but space efficiency is important */
231struct uma_slab_head {
232 uma_keg_t us_keg; /* Keg we live in */
233 union {
234 LIST_ENTRY(uma_slab) _us_link; /* slabs in zone */
235 unsigned long _us_size; /* Size of allocation */
236 } us_type;
237 SLIST_ENTRY(uma_slab) us_hlink; /* Link for hash table */
238 u_int8_t *us_data; /* First item */
239 u_int8_t us_flags; /* Page flags see uma.h */
240 u_int8_t us_freecount; /* How many are free? */
241 u_int8_t us_firstfree; /* First free item index */
242};
243
244/* The standard slab structure */
245struct uma_slab {
246 struct uma_slab_head us_head; /* slab header data */
247 struct {
248 u_int8_t us_item;
249 } us_freelist[1]; /* actual number bigger */
250};
251
252/*
253 * The slab structure for UMA_ZONE_REFCNT zones for whose items we
254 * maintain reference counters in the slab for.
255 */
256struct uma_slab_refcnt {
257 struct uma_slab_head us_head; /* slab header data */
258 struct {
259 u_int8_t us_item;
260 u_int32_t us_refcnt;
261 } us_freelist[1]; /* actual number bigger */
262};
263
264#define us_keg us_head.us_keg
265#define us_link us_head.us_type._us_link
266#define us_size us_head.us_type._us_size
267#define us_hlink us_head.us_hlink
268#define us_data us_head.us_data
269#define us_flags us_head.us_flags
270#define us_freecount us_head.us_freecount
271#define us_firstfree us_head.us_firstfree
272
273typedef struct uma_slab * uma_slab_t;
274typedef struct uma_slab_refcnt * uma_slabrefcnt_t;
275
276/*
277 * These give us the size of one free item reference within our corresponding
278 * uma_slab structures, so that our calculations during zone setup are correct
279 * regardless of what the compiler decides to do with padding the structure
280 * arrays within uma_slab.
281 */
282#define UMA_FRITM_SZ (sizeof(struct uma_slab) - sizeof(struct uma_slab_head))
283#define UMA_FRITMREF_SZ (sizeof(struct uma_slab_refcnt) - \
284 sizeof(struct uma_slab_head))
285
286/*
287 * Zone management structure
288 *
289 * TODO: Optimize for cache line size
290 *
291 */
292struct uma_zone {
293 char *uz_name; /* Text name of the zone */
294 struct mtx *uz_lock; /* Lock for the zone (keg's lock) */
295 uma_keg_t uz_keg; /* Our underlying Keg */
296
297 LIST_ENTRY(uma_zone) uz_link; /* List of all zones in keg */
298 LIST_HEAD(,uma_bucket) uz_full_bucket; /* full buckets */
299 LIST_HEAD(,uma_bucket) uz_free_bucket; /* Buckets for frees */
300
301 uma_ctor uz_ctor; /* Constructor for each allocation */
302 uma_dtor uz_dtor; /* Destructor */
303 uma_init uz_init; /* Initializer for each item */
304 uma_fini uz_fini; /* Discards memory */
305
306 u_int64_t uz_allocs; /* Total number of allocations */
| 29 *
30 */
31
32/*
33 * This file includes definitions, structures, prototypes, and inlines that
34 * should not be used outside of the actual implementation of UMA.
35 */
36
37/*
38 * Here's a quick description of the relationship between the objects:
39 *
40 * Kegs contain lists of slabs which are stored in either the full bin, empty
41 * bin, or partially allocated bin, to reduce fragmentation. They also contain
42 * the user supplied value for size, which is adjusted for alignment purposes
43 * and rsize is the result of that. The Keg also stores information for
44 * managing a hash of page addresses that maps pages to uma_slab_t structures
45 * for pages that don't have embedded uma_slab_t's.
46 *
47 * The uma_slab_t may be embedded in a UMA_SLAB_SIZE chunk of memory or it may
48 * be allocated off the page from a special slab zone. The free list within a
49 * slab is managed with a linked list of indexes, which are 8 bit values. If
50 * UMA_SLAB_SIZE is defined to be too large I will have to switch to 16bit
51 * values. Currently on alpha you can get 250 or so 32 byte items and on x86
52 * you can get 250 or so 16byte items. For item sizes that would yield more
53 * than 10% memory waste we potentially allocate a separate uma_slab_t if this
54 * will improve the number of items per slab that will fit.
55 *
56 * Other potential space optimizations are storing the 8bit of linkage in space
57 * wasted between items due to alignment problems. This may yield a much better
58 * memory footprint for certain sizes of objects. Another alternative is to
59 * increase the UMA_SLAB_SIZE, or allow for dynamic slab sizes. I prefer
60 * dynamic slab sizes because we could stick with 8 bit indexes and only use
61 * large slab sizes for zones with a lot of waste per slab. This may create
62 * ineffeciencies in the vm subsystem due to fragmentation in the address space.
63 *
64 * The only really gross cases, with regards to memory waste, are for those
65 * items that are just over half the page size. You can get nearly 50% waste,
66 * so you fall back to the memory footprint of the power of two allocator. I
67 * have looked at memory allocation sizes on many of the machines available to
68 * me, and there does not seem to be an abundance of allocations at this range
69 * so at this time it may not make sense to optimize for it. This can, of
70 * course, be solved with dynamic slab sizes.
71 *
72 * Kegs may serve multiple Zones but by far most of the time they only serve
73 * one. When a Zone is created, a Keg is allocated and setup for it. While
74 * the backing Keg stores slabs, the Zone caches Buckets of items allocated
75 * from the slabs. Each Zone is equipped with an init/fini and ctor/dtor
76 * pair, as well as with its own set of small per-CPU caches, layered above
77 * the Zone's general Bucket cache.
78 *
79 * The PCPU caches are protected by their own locks, while the Zones backed
80 * by the same Keg all share a common Keg lock (to coalesce contention on
81 * the backing slabs). The backing Keg typically only serves one Zone but
82 * in the case of multiple Zones, one of the Zones is considered the
83 * Master Zone and all Zone-related stats from the Keg are done in the
84 * Master Zone. For an example of a Multi-Zone setup, refer to the
85 * Mbuf allocation code.
86 */
87
88/*
89 * This is the representation for normal (Non OFFPAGE slab)
90 *
91 * i == item
92 * s == slab pointer
93 *
94 * <---------------- Page (UMA_SLAB_SIZE) ------------------>
95 * ___________________________________________________________
96 * | _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ ___________ |
97 * ||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i| |slab header||
98 * ||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_| |___________||
99 * |___________________________________________________________|
100 *
101 *
102 * This is an OFFPAGE slab. These can be larger than UMA_SLAB_SIZE.
103 *
104 * ___________________________________________________________
105 * | _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ |
106 * ||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i||i| |
107 * ||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_||_| |
108 * |___________________________________________________________|
109 * ___________ ^
110 * |slab header| |
111 * |___________|---*
112 *
113 */
114
115#ifndef VM_UMA_INT_H
116#define VM_UMA_INT_H
117
118#define UMA_SLAB_SIZE PAGE_SIZE /* How big are our slabs? */
119#define UMA_SLAB_MASK (PAGE_SIZE - 1) /* Mask to get back to the page */
120#define UMA_SLAB_SHIFT PAGE_SHIFT /* Number of bits PAGE_MASK */
121
122#define UMA_BOOT_PAGES 48 /* Pages allocated for startup */
123
124/* Max waste before going to off page slab management */
125#define UMA_MAX_WASTE (UMA_SLAB_SIZE / 10)
126
127/*
128 * I doubt there will be many cases where this is exceeded. This is the initial
129 * size of the hash table for uma_slabs that are managed off page. This hash
130 * does expand by powers of two. Currently it doesn't get smaller.
131 */
132#define UMA_HASH_SIZE_INIT 32
133
134/*
135 * I should investigate other hashing algorithms. This should yield a low
136 * number of collisions if the pages are relatively contiguous.
137 *
138 * This is the same algorithm that most processor caches use.
139 *
140 * I'm shifting and masking instead of % because it should be faster.
141 */
142
143#define UMA_HASH(h, s) ((((unsigned long)s) >> UMA_SLAB_SHIFT) & \
144 (h)->uh_hashmask)
145
146#define UMA_HASH_INSERT(h, s, mem) \
147 SLIST_INSERT_HEAD(&(h)->uh_slab_hash[UMA_HASH((h), \
148 (mem))], (s), us_hlink);
149#define UMA_HASH_REMOVE(h, s, mem) \
150 SLIST_REMOVE(&(h)->uh_slab_hash[UMA_HASH((h), \
151 (mem))], (s), uma_slab, us_hlink);
152
153/* Hash table for freed address -> slab translation */
154
155SLIST_HEAD(slabhead, uma_slab);
156
157struct uma_hash {
158 struct slabhead *uh_slab_hash; /* Hash table for slabs */
159 int uh_hashsize; /* Current size of the hash table */
160 int uh_hashmask; /* Mask used during hashing */
161};
162
163/*
164 * Structures for per cpu queues.
165 */
166
167struct uma_bucket {
168 LIST_ENTRY(uma_bucket) ub_link; /* Link into the zone */
169 int16_t ub_cnt; /* Count of free items. */
170 int16_t ub_entries; /* Max items. */
171 void *ub_bucket[]; /* actual allocation storage */
172};
173
174typedef struct uma_bucket * uma_bucket_t;
175
176struct uma_cache {
177 uma_bucket_t uc_freebucket; /* Bucket we're freeing to */
178 uma_bucket_t uc_allocbucket; /* Bucket to allocate from */
179 u_int64_t uc_allocs; /* Count of allocations */
180 u_int64_t uc_frees; /* Count of frees */
181};
182
183typedef struct uma_cache * uma_cache_t;
184
185/*
186 * Keg management structure
187 *
188 * TODO: Optimize for cache line size
189 *
190 */
191struct uma_keg {
192 LIST_ENTRY(uma_keg) uk_link; /* List of all kegs */
193
194 struct mtx uk_lock; /* Lock for the keg */
195 struct uma_hash uk_hash;
196
197 LIST_HEAD(,uma_zone) uk_zones; /* Keg's zones */
198 LIST_HEAD(,uma_slab) uk_part_slab; /* partially allocated slabs */
199 LIST_HEAD(,uma_slab) uk_free_slab; /* empty slab list */
200 LIST_HEAD(,uma_slab) uk_full_slab; /* full slabs */
201
202 u_int32_t uk_recurse; /* Allocation recursion count */
203 u_int32_t uk_align; /* Alignment mask */
204 u_int32_t uk_pages; /* Total page count */
205 u_int32_t uk_free; /* Count of items free in slabs */
206 u_int32_t uk_size; /* Requested size of each item */
207 u_int32_t uk_rsize; /* Real size of each item */
208 u_int32_t uk_maxpages; /* Maximum number of pages to alloc */
209
210 uma_init uk_init; /* Keg's init routine */
211 uma_fini uk_fini; /* Keg's fini routine */
212 uma_alloc uk_allocf; /* Allocation function */
213 uma_free uk_freef; /* Free routine */
214
215 struct vm_object *uk_obj; /* Zone specific object */
216 vm_offset_t uk_kva; /* Base kva for zones with objs */
217 uma_zone_t uk_slabzone; /* Slab zone backing us, if OFFPAGE */
218
219 u_int16_t uk_pgoff; /* Offset to uma_slab struct */
220 u_int16_t uk_ppera; /* pages per allocation from backend */
221 u_int16_t uk_ipers; /* Items per slab */
222 u_int16_t uk_flags; /* Internal flags */
223};
224
225/* Simpler reference to uma_keg for internal use. */
226typedef struct uma_keg * uma_keg_t;
227
228/* Page management structure */
229
230/* Sorry for the union, but space efficiency is important */
231struct uma_slab_head {
232 uma_keg_t us_keg; /* Keg we live in */
233 union {
234 LIST_ENTRY(uma_slab) _us_link; /* slabs in zone */
235 unsigned long _us_size; /* Size of allocation */
236 } us_type;
237 SLIST_ENTRY(uma_slab) us_hlink; /* Link for hash table */
238 u_int8_t *us_data; /* First item */
239 u_int8_t us_flags; /* Page flags see uma.h */
240 u_int8_t us_freecount; /* How many are free? */
241 u_int8_t us_firstfree; /* First free item index */
242};
243
244/* The standard slab structure */
245struct uma_slab {
246 struct uma_slab_head us_head; /* slab header data */
247 struct {
248 u_int8_t us_item;
249 } us_freelist[1]; /* actual number bigger */
250};
251
252/*
253 * The slab structure for UMA_ZONE_REFCNT zones for whose items we
254 * maintain reference counters in the slab for.
255 */
256struct uma_slab_refcnt {
257 struct uma_slab_head us_head; /* slab header data */
258 struct {
259 u_int8_t us_item;
260 u_int32_t us_refcnt;
261 } us_freelist[1]; /* actual number bigger */
262};
263
264#define us_keg us_head.us_keg
265#define us_link us_head.us_type._us_link
266#define us_size us_head.us_type._us_size
267#define us_hlink us_head.us_hlink
268#define us_data us_head.us_data
269#define us_flags us_head.us_flags
270#define us_freecount us_head.us_freecount
271#define us_firstfree us_head.us_firstfree
272
273typedef struct uma_slab * uma_slab_t;
274typedef struct uma_slab_refcnt * uma_slabrefcnt_t;
275
276/*
277 * These give us the size of one free item reference within our corresponding
278 * uma_slab structures, so that our calculations during zone setup are correct
279 * regardless of what the compiler decides to do with padding the structure
280 * arrays within uma_slab.
281 */
282#define UMA_FRITM_SZ (sizeof(struct uma_slab) - sizeof(struct uma_slab_head))
283#define UMA_FRITMREF_SZ (sizeof(struct uma_slab_refcnt) - \
284 sizeof(struct uma_slab_head))
285
286/*
287 * Zone management structure
288 *
289 * TODO: Optimize for cache line size
290 *
291 */
292struct uma_zone {
293 char *uz_name; /* Text name of the zone */
294 struct mtx *uz_lock; /* Lock for the zone (keg's lock) */
295 uma_keg_t uz_keg; /* Our underlying Keg */
296
297 LIST_ENTRY(uma_zone) uz_link; /* List of all zones in keg */
298 LIST_HEAD(,uma_bucket) uz_full_bucket; /* full buckets */
299 LIST_HEAD(,uma_bucket) uz_free_bucket; /* Buckets for frees */
300
301 uma_ctor uz_ctor; /* Constructor for each allocation */
302 uma_dtor uz_dtor; /* Destructor */
303 uma_init uz_init; /* Initializer for each item */
304 uma_fini uz_fini; /* Discards memory */
305
306 u_int64_t uz_allocs; /* Total number of allocations */
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307 u_int64_t uz_frees; /* total number of frees */
| 307 u_int64_t uz_frees; /* Total number of frees */
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308 uint16_t uz_fills; /* Outstanding bucket fills */
309 uint16_t uz_count; /* Highest value ub_ptr can have */
310
311 /*
312 * This HAS to be the last item because we adjust the zone size
313 * based on NCPU and then allocate the space for the zones.
314 */
315 struct uma_cache uz_cpu[1]; /* Per cpu caches */
316};
317
318/*
319 * These flags must not overlap with the UMA_ZONE flags specified in uma.h.
320 */
321#define UMA_ZFLAG_PRIVALLOC 0x1000 /* Use uz_allocf. */
322#define UMA_ZFLAG_INTERNAL 0x2000 /* No offpage no PCPU. */
323#define UMA_ZFLAG_FULL 0x4000 /* Reached uz_maxpages */
324#define UMA_ZFLAG_CACHEONLY 0x8000 /* Don't ask VM for buckets. */
325
326/* Internal prototypes */
327static __inline uma_slab_t hash_sfind(struct uma_hash *hash, u_int8_t *data);
328void *uma_large_malloc(int size, int wait);
329void uma_large_free(uma_slab_t slab);
330
331/* Lock Macros */
332
333#define ZONE_LOCK_INIT(z, lc) \
334 do { \
335 if ((lc)) \
336 mtx_init((z)->uz_lock, (z)->uz_name, \
337 (z)->uz_name, MTX_DEF | MTX_DUPOK); \
338 else \
339 mtx_init((z)->uz_lock, (z)->uz_name, \
340 "UMA zone", MTX_DEF | MTX_DUPOK); \
341 } while (0)
342
343#define ZONE_LOCK_FINI(z) mtx_destroy((z)->uz_lock)
344#define ZONE_LOCK(z) mtx_lock((z)->uz_lock)
345#define ZONE_UNLOCK(z) mtx_unlock((z)->uz_lock)
346
347/*
348 * Find a slab within a hash table. This is used for OFFPAGE zones to lookup
349 * the slab structure.
350 *
351 * Arguments:
352 * hash The hash table to search.
353 * data The base page of the item.
354 *
355 * Returns:
356 * A pointer to a slab if successful, else NULL.
357 */
358static __inline uma_slab_t
359hash_sfind(struct uma_hash *hash, u_int8_t *data)
360{
361 uma_slab_t slab;
362 int hval;
363
364 hval = UMA_HASH(hash, data);
365
366 SLIST_FOREACH(slab, &hash->uh_slab_hash[hval], us_hlink) {
367 if ((u_int8_t *)slab->us_data == data)
368 return (slab);
369 }
370 return (NULL);
371}
372
373static __inline uma_slab_t
374vtoslab(vm_offset_t va)
375{
376 vm_page_t p;
377 uma_slab_t slab;
378
379 p = PHYS_TO_VM_PAGE(pmap_kextract(va));
380 slab = (uma_slab_t )p->object;
381
382 if (p->flags & PG_SLAB)
383 return (slab);
384 else
385 return (NULL);
386}
387
388static __inline void
389vsetslab(vm_offset_t va, uma_slab_t slab)
390{
391 vm_page_t p;
392
393 p = PHYS_TO_VM_PAGE(pmap_kextract(va));
394 p->object = (vm_object_t)slab;
395 p->flags |= PG_SLAB;
396}
397
398static __inline void
399vsetobj(vm_offset_t va, vm_object_t obj)
400{
401 vm_page_t p;
402
403 p = PHYS_TO_VM_PAGE(pmap_kextract(va));
404 p->object = obj;
405 p->flags &= ~PG_SLAB;
406}
407
408/*
409 * The following two functions may be defined by architecture specific code
410 * if they can provide more effecient allocation functions. This is useful
411 * for using direct mapped addresses.
412 */
413void *uma_small_alloc(uma_zone_t zone, int bytes, u_int8_t *pflag, int wait);
414void uma_small_free(void *mem, int size, u_int8_t flags);
415
416#endif /* VM_UMA_INT_H */
| 308 uint16_t uz_fills; /* Outstanding bucket fills */
309 uint16_t uz_count; /* Highest value ub_ptr can have */
310
311 /*
312 * This HAS to be the last item because we adjust the zone size
313 * based on NCPU and then allocate the space for the zones.
314 */
315 struct uma_cache uz_cpu[1]; /* Per cpu caches */
316};
317
318/*
319 * These flags must not overlap with the UMA_ZONE flags specified in uma.h.
320 */
321#define UMA_ZFLAG_PRIVALLOC 0x1000 /* Use uz_allocf. */
322#define UMA_ZFLAG_INTERNAL 0x2000 /* No offpage no PCPU. */
323#define UMA_ZFLAG_FULL 0x4000 /* Reached uz_maxpages */
324#define UMA_ZFLAG_CACHEONLY 0x8000 /* Don't ask VM for buckets. */
325
326/* Internal prototypes */
327static __inline uma_slab_t hash_sfind(struct uma_hash *hash, u_int8_t *data);
328void *uma_large_malloc(int size, int wait);
329void uma_large_free(uma_slab_t slab);
330
331/* Lock Macros */
332
333#define ZONE_LOCK_INIT(z, lc) \
334 do { \
335 if ((lc)) \
336 mtx_init((z)->uz_lock, (z)->uz_name, \
337 (z)->uz_name, MTX_DEF | MTX_DUPOK); \
338 else \
339 mtx_init((z)->uz_lock, (z)->uz_name, \
340 "UMA zone", MTX_DEF | MTX_DUPOK); \
341 } while (0)
342
343#define ZONE_LOCK_FINI(z) mtx_destroy((z)->uz_lock)
344#define ZONE_LOCK(z) mtx_lock((z)->uz_lock)
345#define ZONE_UNLOCK(z) mtx_unlock((z)->uz_lock)
346
347/*
348 * Find a slab within a hash table. This is used for OFFPAGE zones to lookup
349 * the slab structure.
350 *
351 * Arguments:
352 * hash The hash table to search.
353 * data The base page of the item.
354 *
355 * Returns:
356 * A pointer to a slab if successful, else NULL.
357 */
358static __inline uma_slab_t
359hash_sfind(struct uma_hash *hash, u_int8_t *data)
360{
361 uma_slab_t slab;
362 int hval;
363
364 hval = UMA_HASH(hash, data);
365
366 SLIST_FOREACH(slab, &hash->uh_slab_hash[hval], us_hlink) {
367 if ((u_int8_t *)slab->us_data == data)
368 return (slab);
369 }
370 return (NULL);
371}
372
373static __inline uma_slab_t
374vtoslab(vm_offset_t va)
375{
376 vm_page_t p;
377 uma_slab_t slab;
378
379 p = PHYS_TO_VM_PAGE(pmap_kextract(va));
380 slab = (uma_slab_t )p->object;
381
382 if (p->flags & PG_SLAB)
383 return (slab);
384 else
385 return (NULL);
386}
387
388static __inline void
389vsetslab(vm_offset_t va, uma_slab_t slab)
390{
391 vm_page_t p;
392
393 p = PHYS_TO_VM_PAGE(pmap_kextract(va));
394 p->object = (vm_object_t)slab;
395 p->flags |= PG_SLAB;
396}
397
398static __inline void
399vsetobj(vm_offset_t va, vm_object_t obj)
400{
401 vm_page_t p;
402
403 p = PHYS_TO_VM_PAGE(pmap_kextract(va));
404 p->object = obj;
405 p->flags &= ~PG_SLAB;
406}
407
408/*
409 * The following two functions may be defined by architecture specific code
410 * if they can provide more effecient allocation functions. This is useful
411 * for using direct mapped addresses.
412 */
413void *uma_small_alloc(uma_zone_t zone, int bytes, u_int8_t *pflag, int wait);
414void uma_small_free(void *mem, int size, u_int8_t flags);
415
416#endif /* VM_UMA_INT_H */
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