diff options
author | Alan Korr <alkorr@rockbox.org> | 2002-04-15 23:19:10 +0000 |
---|---|---|
committer | Alan Korr <alkorr@rockbox.org> | 2002-04-15 23:19:10 +0000 |
commit | 27df7b0b96686771b9fafba33d0a97b4d77f6206 (patch) | |
tree | 638189ff3754910b98f4725167fe621c4c20436a /firmware/test/memory/memory-slab.c | |
parent | f5747cf78a4506dca544fde5324fd020a988c73b (diff) | |
download | rockbox-27df7b0b96686771b9fafba33d0a97b4d77f6206.tar.gz rockbox-27df7b0b96686771b9fafba33d0a97b4d77f6206.zip |
*** empty log message ***
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@98 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'firmware/test/memory/memory-slab.c')
-rw-r--r-- | firmware/test/memory/memory-slab.c | 463 |
1 files changed, 463 insertions, 0 deletions
diff --git a/firmware/test/memory/memory-slab.c b/firmware/test/memory/memory-slab.c new file mode 100644 index 0000000000..289818b24a --- /dev/null +++ b/firmware/test/memory/memory-slab.c | |||
@@ -0,0 +1,463 @@ | |||
1 | /*************************************************************************** | ||
2 | * __________ __ ___. | ||
3 | * Open \______ \ ____ ____ | | _\_ |__ _______ ___ | ||
4 | * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / | ||
5 | * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < | ||
6 | * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ | ||
7 | * \/ \/ \/ \/ \/ | ||
8 | * $Id: | ||
9 | * | ||
10 | * Copyright (C) 2002 by Alan Korr | ||
11 | * | ||
12 | * All files in this archive are subject to the GNU General Public License. | ||
13 | * See the file COPYING in the source tree root for full license agreement. | ||
14 | * | ||
15 | * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY | ||
16 | * KIND, either express or implied. | ||
17 | * | ||
18 | ****************************************************************************/ | ||
19 | #if 0 | ||
20 | |||
21 | #include <memory.h> | ||
22 | |||
23 | static struct memory_cache *free_block_cache[MEMORY_PAGE_MINIMAL_SIZE - ]; | ||
24 | static struct memory_cache *cache_list; | ||
25 | |||
26 | static inline int get_order (unsigned size) | ||
27 | { | ||
28 | int order = 0; | ||
29 | size = (size + sizeof(struct memory_free_block) - 1) & - sizeof(struct memory_free_block); | ||
30 | while (size > 0) | ||
31 | { | ||
32 | ++order; size <<= 1; | ||
33 | } | ||
34 | return order; | ||
35 | } | ||
36 | |||
37 | static inline struct memory_slab *get_slab (struct memory_cache *cache,void *address) | ||
38 | { | ||
39 | #ifdef TEST | ||
40 | return (struct memory_slab *)((((unsigned)address + cache->page_size) & -cache->page_size) - sizeof (struct memory_slab)); | ||
41 | #else | ||
42 | return (struct memory_slab *)((free_page + (((unsigned)address - free_page + cache->page_size) & -cache->page_size) - sizeof (struct memory_slab))); | ||
43 | #endif | ||
44 | } | ||
45 | |||
46 | static struct memory_cache *splay_cache (struct memory_cache *root,unsigned int left) | ||
47 | { | ||
48 | struct memory_cache *down; | ||
49 | struct memory_cache *less; | ||
50 | struct memory_cache *more; | ||
51 | struct memory_cache head; | ||
52 | head.less = | ||
53 | head.more = 0; | ||
54 | less = | ||
55 | more = &head; | ||
56 | while (1) | ||
57 | { | ||
58 | if (left < root->left) | ||
59 | { | ||
60 | if ((down = root->less)) | ||
61 | { | ||
62 | if (left < down->left) | ||
63 | { | ||
64 | root->less = down->more; | ||
65 | down->more = root; | ||
66 | root = down; | ||
67 | if (!root->less) | ||
68 | break; | ||
69 | } | ||
70 | more->less = root; | ||
71 | more = root; | ||
72 | root = root->less; | ||
73 | continue; | ||
74 | } | ||
75 | break; | ||
76 | } | ||
77 | if (root->left < left) | ||
78 | { | ||
79 | if ((down = root->more)) | ||
80 | { | ||
81 | if (root->left < left) | ||
82 | { | ||
83 | root->more = down->less; | ||
84 | down->less = root; | ||
85 | root = down; | ||
86 | if (!root->more) | ||
87 | break; | ||
88 | } | ||
89 | less->more = root; | ||
90 | less = root; | ||
91 | root = root->more; | ||
92 | continue; | ||
93 | } | ||
94 | } | ||
95 | break; | ||
96 | } | ||
97 | less->more = root->less; | ||
98 | more->less = root->more; | ||
99 | root->less = head.more; | ||
100 | root->more = head.less; | ||
101 | return root; | ||
102 | } | ||
103 | |||
104 | static inline struct memory_cache *insert_cache (struct memory_cache *root,struct memory_cache *node) | ||
105 | { | ||
106 | node->less = | ||
107 | node->more = | ||
108 | node->same = 0; | ||
109 | if (root) | ||
110 | { | ||
111 | if (node->left == ((root = splay_cache (root,node))->left)) | ||
112 | { | ||
113 | node->less = root.less; | ||
114 | node->more = root.more; | ||
115 | node->same = root; | ||
116 | root->less = node; | ||
117 | } | ||
118 | else if (node < root) | ||
119 | { | ||
120 | node->less = root->less; | ||
121 | node->more = root; | ||
122 | root->less = 0; | ||
123 | } | ||
124 | else | ||
125 | { | ||
126 | node->less = root; | ||
127 | node->more = root->more; | ||
128 | node->more = 0; | ||
129 | } | ||
130 | } | ||
131 | return node; | ||
132 | } | ||
133 | |||
134 | static inline struct memory_cache *remove_cache (struct memory_cache *root,struct memory_cache *node) | ||
135 | { | ||
136 | if (root) | ||
137 | { | ||
138 | root = splay_cache (root,node); | ||
139 | if (root != node) | ||
140 | { | ||
141 | node->less->same = node->same; | ||
142 | if (node->same) | ||
143 | node->same->less = node->less; | ||
144 | return root; | ||
145 | } | ||
146 | if (root->less) | ||
147 | { | ||
148 | node = splay_page (root->less,node); | ||
149 | node->more = root->more; | ||
150 | } | ||
151 | else | ||
152 | node = root->more; | ||
153 | } | ||
154 | return root; | ||
155 | } | ||
156 | |||
157 | static inline struct memory_cache *move_cache (struct memory_cache *root,struct memory_cache *node,int delta) | ||
158 | { | ||
159 | if ((root = remove_cache (root,node))) | ||
160 | { | ||
161 | node->left += delta; | ||
162 | root = insert_cache (root,node); | ||
163 | } | ||
164 | return root; | ||
165 | } | ||
166 | |||
167 | static inline struct memory_slab *push_slab (struct memory_cache *head,struct memory_cache *node) | ||
168 | { | ||
169 | node->less = head; | ||
170 | if (head) | ||
171 | { | ||
172 | node->more = head->more; | ||
173 | head->more = node; | ||
174 | } | ||
175 | else | ||
176 | node->more = 0; | ||
177 | return node; | ||
178 | } | ||
179 | |||
180 | static inline struct memory_slab *pop_slab (struct memory_cache *head,struct memory_cache *node) | ||
181 | { | ||
182 | if (head) | ||
183 | head->more = node->more; | ||
184 | return node->more; | ||
185 | } | ||
186 | |||
187 | static inline struct memory_slab *move_slab (struct memory_slab **from,struct memory_slab **to) | ||
188 | { | ||
189 | struct memory_slab *head = *from; | ||
190 | *from = (*from)->more; | ||
191 | if (*from) | ||
192 | (*from)->less = head->less; | ||
193 | head->less = 0; | ||
194 | head->more = (*to); | ||
195 | if (*to) | ||
196 | (*to)->prev = head; | ||
197 | *to = head; | ||
198 | return head; | ||
199 | } | ||
200 | |||
201 | |||
202 | /*****************************************************************************/ | ||
203 | /* PUBLIC FUNCTIONS */ | ||
204 | /*****************************************************************************/ | ||
205 | |||
206 | /////////////////////////////////////////////////////////////////////////////// | ||
207 | // MEMORY CACHE : | ||
208 | ///////////////// | ||
209 | // | ||
210 | // - memory_grow_cache : allocate a new slab for a cache | ||
211 | // - memory_shrink_cache : release free slabs from a cache | ||
212 | // - memory_create_cache : create a new cache of size-fixed blocks | ||
213 | // - memory_destroy_cache : destroy the cache and release all the slabs | ||
214 | // - memory_cache_allocate : allocate a block from the cache | ||
215 | // - memory_cache_release : release a block in the cache | ||
216 | // | ||
217 | |||
218 | struct memory_slab *memory_grow_cache (struct memory_cache *cache) | ||
219 | { | ||
220 | struct memory_slab *slab; | ||
221 | unsigned int page; | ||
222 | if (cache) | ||
223 | { | ||
224 | page = (unsigned int)memory_allocate_page (cache->page_order); | ||
225 | if (page) | ||
226 | { | ||
227 | struct memory_free_block *block,**link; | ||
228 | slab = (struct memory_slab *)(page + cache->page_size - sizeof (struct memory_slab)); | ||
229 | slab->free = 0; | ||
230 | slab->left = 0; | ||
231 | link = &slab->free; | ||
232 | for ((unsigned int)block = page; | ||
233 | (unsigned int)block + cache->size < (unsigned int)slab; | ||
234 | (unsigned int)block += cache->size) | ||
235 | { | ||
236 | *link = block; | ||
237 | link = &block->link; | ||
238 | ++slab->free; | ||
239 | } | ||
240 | *link = 0; | ||
241 | cache->blocks_per_slab = slab->free; | ||
242 | cache->reap = push_slab (cache->reap,slab); | ||
243 | cache_list = move_cache (cache_list,cache,+1); | ||
244 | return slab; | ||
245 | } | ||
246 | } | ||
247 | return MEMORY_RETURN_FAILURE; | ||
248 | } | ||
249 | |||
250 | static int memory_shrink_cache (struct memory_cache *cache,int all,int move) | ||
251 | { | ||
252 | struct memory_slab *slab; | ||
253 | unsigned int slabs = 0; | ||
254 | if (cache) | ||
255 | { | ||
256 | while ((slab = cache->reap)) | ||
257 | { | ||
258 | ++slabs; | ||
259 | cache->reap = pop_slab (cache->reap,slab); | ||
260 | memory_release_page ((void *)slab); | ||
261 | if (all) | ||
262 | continue; | ||
263 | if (move) | ||
264 | cache_list = move_cache (cache_list,cache,-slabs); | ||
265 | return MEMORY_RETURN_SUCCESS; | ||
266 | } | ||
267 | } | ||
268 | return MEMORY_RETURN_FAILURE; | ||
269 | } | ||
270 | |||
271 | int memory_shrink_cache (struct memory_cache *cache,int all) | ||
272 | { | ||
273 | return shrink_cache (cache,all,1 /* move cache in cache_list */); | ||
274 | } | ||
275 | |||
276 | struct memory_cache *memory_create_cache (unsigned int size,int align,int flags) | ||
277 | { | ||
278 | struct memory_cache *cache; | ||
279 | unsigned int waste = 0,blocks_per_page; | ||
280 | int page_order; | ||
281 | unsigned int page_size; | ||
282 | unsigned int original_size = size; | ||
283 | |||
284 | // Align size on 'align' bytes ('align' should equal 1<<n) | ||
285 | // if 'align' is inferior to 4, 32-bit word alignment is done by default. | ||
286 | size = (align > 4) ? ((size + align - 1) & -align) : ((size + sizeof (int) - 1) & -sizeof (int)); | ||
287 | if (!(cache = memory_cache_allocate (&cache_cache)) | ||
288 | return MEMORY_RETURN_FAILURE; | ||
289 | |||
290 | cache->flags = | ||
291 | cache->left = 0; | ||
292 | |||
293 | cache->used = | ||
294 | cache->free = | ||
295 | cache->reap = 0; | ||
296 | |||
297 | cache->original_size = original_size; | ||
298 | cache->size = size; | ||
299 | |||
300 | page_size = 0; | ||
301 | page_order = MEMORY_PAGE_MINIMAL_SIZE;; | ||
302 | |||
303 | // Trying to determine what is the best number of pages per slab | ||
304 | for (;; ++order,(page_size <<= 1)) | ||
305 | { | ||
306 | if (page_order >= MEMORY_MAXIMUM_PAGE_ORDER_PER_SLAB) | ||
307 | { | ||
308 | memory_cache_release (&cache_cache,cache); | ||
309 | return MEMORY_RETURN_FAILURE; | ||
310 | } | ||
311 | |||
312 | waste = page_size; | ||
313 | waste -= sizeof (struct memory_slab); | ||
314 | |||
315 | blocks_per_slab = waste / size; | ||
316 | waste -= block_per_slab * size; | ||
317 | |||
318 | if (blocks_per_slab < MEMORY_MINIMUM_BLOCKS_PER_SLAB) | ||
319 | { | ||
320 | ++page_order; page_size <<= 1; | ||
321 | continue; | ||
322 | } | ||
323 | |||
324 | // below 3% of lost space is correct | ||
325 | if ((waste << 16) / page_size) < 1967) | ||
326 | break; | ||
327 | ++page_order; page_size <<= 1; | ||
328 | } | ||
329 | |||
330 | cache->page_size = page_size; | ||
331 | cache->page_order = page_order; | ||
332 | |||
333 | cache_list = insert_cache (cache_list,cache); | ||
334 | |||
335 | return cache; | ||
336 | } | ||
337 | |||
338 | int memory_destroy_cache (struct memory_cache *cache) | ||
339 | { | ||
340 | if (cache) | ||
341 | { | ||
342 | cache_list = remove_cache (cache_list,cache); | ||
343 | if (shrink_cache (cache,1 /* release all free slabs */,0 /* don't move in cache_list */)) | ||
344 | return memory_cache_release (&cache_cache,cache); | ||
345 | } | ||
346 | return MEMORY_RETURN_FAILURE; | ||
347 | } | ||
348 | |||
349 | void *memory_cache_allocate (struct memory_cache *cache) | ||
350 | { | ||
351 | if (cache) | ||
352 | { | ||
353 | do | ||
354 | { | ||
355 | struct memory_slab *slab; | ||
356 | if ((slab = cache->free)) | ||
357 | { | ||
358 | if (slab->left > 0) | ||
359 | { | ||
360 | ok: struct memory_free_block *block = slab->free; | ||
361 | slab->free = block->link; | ||
362 | if (--slab->left == 0) | ||
363 | move_slab (&cache->free,&cache->used); | ||
364 | return block; | ||
365 | } | ||
366 | } | ||
367 | if (cache->reap) | ||
368 | { | ||
369 | slab = move_slab (&cache->reap,&cache->free); | ||
370 | cache_list = move_cache (cache_list,cache,-1); | ||
371 | goto ok; | ||
372 | } | ||
373 | } | ||
374 | while (grow_cache (cache)); | ||
375 | } | ||
376 | return MEMORY_RETURN_FAILURE; | ||
377 | } | ||
378 | |||
379 | int memory_cache_release (struct memory_cache *cache,void *address) | ||
380 | { | ||
381 | struct memory_slab *slab = get_slab (cache,address); | ||
382 | slab->free = (struct memory_free_block *)address; | ||
383 | if (slab->left++ == 0) | ||
384 | move_slab (&cache->used,&cache->free); | ||
385 | else if (slab->left == cache->elements_per_slab) | ||
386 | { | ||
387 | move_slab (&cache->free,&cache->reap); | ||
388 | cache_list = move_cache (cache_list,cache,+1); | ||
389 | } | ||
390 | return MEMORY_RETURN_SUCCESS; | ||
391 | } | ||
392 | |||
393 | |||
394 | /////////////////////////////////////////////////////////////////////////////// | ||
395 | // MEMORY BLOCK : | ||
396 | ///////////////// | ||
397 | // | ||
398 | // - memory_allocate_small_block : allocate a small block (no page) | ||
399 | // - memory_release_small_block : release a small block (no page) | ||
400 | // - memory_allocate_block : allocate a block (or a page) | ||
401 | // - memory_release_block : release a block (or a page) | ||
402 | // | ||
403 | |||
404 | static inline void *allocate_small_block (int order) | ||
405 | { | ||
406 | struct memory_cache *cache = free_block_cache[order]; | ||
407 | do | ||
408 | { | ||
409 | if (cache) | ||
410 | return memory_cache_allocate (cache); | ||
411 | } | ||
412 | while ((free_block_cache[order] = cache = memory_create_cache (size,0,0))); | ||
413 | return MEMORY_RETURN_FAILURE; | ||
414 | } | ||
415 | |||
416 | void *memory_allocate_small_block (int order) | ||
417 | { | ||
418 | if (order < MEMORY_PAGE_MINIMAL_ORDER) | ||
419 | return allocate_small_block (order) | ||
420 | return MEMORY_RETURN_FAILURE; | ||
421 | } | ||
422 | |||
423 | static inline int release_small_block (int order,void *address) | ||
424 | { | ||
425 | struct memory_cache *cache = free_block_cache[order]; | ||
426 | if (cache) | ||
427 | return memory_cache_release (cache,address); | ||
428 | return MEMORY_RETURN_FAILURE; | ||
429 | } | ||
430 | |||
431 | int memory_release_small_block (int order,void *address) | ||
432 | { | ||
433 | if (order < MEMORY_PAGE_MINIMAL_ORDER) | ||
434 | return memory_release_small_block (order,address); | ||
435 | return memory_release_page (address); | ||
436 | } | ||
437 | |||
438 | void *memory_allocate_block (unsigned int size) | ||
439 | { | ||
440 | size += sizeof (int *); | ||
441 | int order = get_order (size); | ||
442 | if (size < MEMORY_PAGE_MINIMAL_SIZE) | ||
443 | { | ||
444 | int *block = (int *)allocate_block (order); | ||
445 | *block = order; | ||
446 | return block; | ||
447 | } | ||
448 | if (size < MEMORY_PAGE_MAXIMAL_SIZE) | ||
449 | return memory_allocate_page (order); | ||
450 | return MEMORY_RETURN_FAILURE; | ||
451 | } | ||
452 | |||
453 | int memory_release_block (void *address) | ||
454 | { | ||
455 | int order = *((int *)address); | ||
456 | if (order < MEMORY_PAGE_MINIMAL_ORDER) | ||
457 | return release_block (order); | ||
458 | if (order < MEMORY_PAGE_MAXIMAL_ORDER) | ||
459 | return memory_release_page (address); | ||
460 | return MEMORY_RETURN_FAILURE; | ||
461 | } | ||
462 | |||
463 | #endif \ No newline at end of file | ||