1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
|
/*
ChibiOS - Copyright (C) 2006..2019 Giovanni Di Sirio.
This file is part of ChibiOS.
ChibiOS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file oslib/include/chobjcaches.h
* @brief Objects Caches macros and structures.
*
* @addtogroup oslib_objchaches
* @{
*/
#ifndef CHOBJCACHES_H
#define CHOBJCACHES_H
#if (CH_CFG_USE_OBJ_CACHES == TRUE) || defined(__DOXYGEN__)
/*===========================================================================*/
/* Module constants. */
/*===========================================================================*/
/**
* @name Cached objects flags
* @{
*/
#define OC_FLAG_INLRU 0x00000001U
#define OC_FLAG_INHASH 0x00000002U
#define OC_FLAG_SHARED 0x00000004U
#define OC_FLAG_NOTSYNC 0x00000008U
#define OC_FLAG_LAZYWRITE 0x00000010U
#define OC_FLAG_FORGET 0x00000020U
/** @} */
/*===========================================================================*/
/* Module pre-compile time settings. */
/*===========================================================================*/
/*===========================================================================*/
/* Derived constants and error checks. */
/*===========================================================================*/
/*===========================================================================*/
/* Module data structures and types. */
/*===========================================================================*/
/**
* @brief Flags of cached objects.
*/
typedef uint32_t oc_flags_t;
/**
* @brief Type of an hash element header.
*/
typedef struct ch_oc_hash_header oc_hash_header_t;
/**
* @brief Type of an LRU element header.
*/
typedef struct ch_oc_lru_header oc_lru_header_t;
/**
* @brief Type of a cached object.
*/
typedef struct ch_oc_object oc_object_t;
/**
* @brief Type of a cache object.
*/
typedef struct ch_objects_cache objects_cache_t;
/**
* @brief Object read function.
*
* @param[in] ocp pointer to the @p objects_cache_t structure
* @param[in] async requests an asynchronous operation if supported, the
* function is then responsible for releasing the
* object
*/
typedef bool (*oc_readf_t)(objects_cache_t *ocp,
oc_object_t *objp,
bool async);
/**
* @brief Object write function.
*
* @param[in] ocp pointer to the @p objects_cache_t structure
* @param[in] async requests an asynchronous operation if supported, the
* function is then responsible for releasing the
* object
*/
typedef bool (*oc_writef_t)(objects_cache_t *ocp,
oc_object_t *objp,
bool async);
/**
* @brief Structure representing an hash table element.
*/
struct ch_oc_hash_header {
/**
* @brief Next in the collisions list.
*/
oc_object_t *hash_next;
/**
* @brief Previous in the collisions list.
*/
oc_object_t *hash_prev;
};
/**
* @brief Structure representing an hash table element.
*/
struct ch_oc_lru_header {
/**
* @brief Next in the collisions list.
*/
oc_object_t *hash_next;
/**
* @brief Previous in the collisions list.
*/
oc_object_t *hash_prev;
/**
* @brief Next in the LRU list.
*/
oc_object_t *lru_next;
/**
* @brief Previous in the LRU list.
*/
oc_object_t *lru_prev;
};
/**
* @brief Structure representing a cached object.
*/
struct ch_oc_object {
/**
* @brief Next in the collisions list.
*/
oc_object_t *hash_next;
/**
* @brief Previous in the collisions list.
*/
oc_object_t *hash_prev;
/**
* @brief Next in the LRU list.
*/
oc_object_t *lru_next;
/**
* @brief Previous in the LRU list.
*/
oc_object_t *lru_prev;
/**
* @brief Object group.
*/
uint32_t obj_group;
/**
* @brief Object key.
*/
uint32_t obj_key;
/**
* @brief Semaphore for object access.
*/
semaphore_t obj_sem;
/**
* @brief Object flags.
*/
oc_flags_t obj_flags;
/**
* @brief User pointer.
* @note This pointer can be used to refer to external buffers,
* @p chCacheObjectInit() initializes it to @p NULL.
*/
void *dptr;
};
/**
* @brief Structure representing a cache object.
*/
struct ch_objects_cache {
/**
* @brief Number of elements in the hash table.
*/
ucnt_t hashn;
/**
* @brief Pointer to the hash table.
*/
oc_hash_header_t *hashp;
/**
* @brief Number of elements in the objects table.
*/
ucnt_t objn;
/**
* @brief Size of elements in the objects table.
*/
size_t objsz;
/**
* @brief Pointer to the objects table.
*/
void *objvp;
/**
* @brief LRU list header.
*/
oc_lru_header_t lru;
/**
* @brief Semaphore for cache access.
*/
semaphore_t cache_sem;
/**
* @brief Semaphore for LRU access.
*/
semaphore_t lru_sem;
/**
* @brief Reader functions for cached objects.
*/
oc_readf_t readf;
/**
* @brief Writer functions for cached objects.
*/
oc_writef_t writef;
};
/*===========================================================================*/
/* Module macros. */
/*===========================================================================*/
/*===========================================================================*/
/* External declarations. */
/*===========================================================================*/
#ifdef __cplusplus
extern "C" {
#endif
void chCacheObjectInit(objects_cache_t *ocp,
ucnt_t hashn,
oc_hash_header_t *hashp,
ucnt_t objn,
size_t objsz,
void *objvp,
oc_readf_t readf,
oc_writef_t writef);
oc_object_t *chCacheGetObject(objects_cache_t *ocp,
uint32_t group,
uint32_t key);
void chCacheReleaseObjectI(objects_cache_t *ocp,
oc_object_t *objp);
bool chCacheReadObject(objects_cache_t *ocp,
oc_object_t *objp,
bool async);
bool chCacheWriteObject(objects_cache_t *ocp,
oc_object_t *objp,
bool async);
#ifdef __cplusplus
}
#endif
/*===========================================================================*/
/* Module inline functions. */
/*===========================================================================*/
/**
* @brief Releases an object into the cache.
* @note This function gives a meaning to the following flags:
* - @p OC_FLAG_INLRU must be cleared.
* - @p OC_FLAG_INHASH must be set.
* - @p OC_FLAG_SHARED must be cleared.
* - @p OC_FLAG_NOTSYNC invalidates the object and queues it on
* the LRU tail.
* - @p OC_FLAG_LAZYWRITE is ignored and kept, a write will occur
* when the object is removed from the LRU list (lazy write).
* .
*
* @param[in] ocp pointer to the @p objects_cache_t structure
* @param[in] objp pointer to the @p oc_object_t structure
*
* @api
*/
static inline void chCacheReleaseObject(objects_cache_t *ocp,
oc_object_t *objp) {
chSysLock();
chCacheReleaseObjectI(ocp, objp);
chSchRescheduleS();
chSysUnlock();
}
#endif /* CH_CFG_USE_OBJ_CACHES == TRUE */
#endif /* CHOBJCACHES_H */
/** @} */
|
