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author | Alan Korr <alkorr@rockbox.org> | 2002-04-17 13:01:09 +0000 |
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committer | Alan Korr <alkorr@rockbox.org> | 2002-04-17 13:01:09 +0000 |
commit | e0ae9dc0081033be009d3e60b043e89e1e8d243f (patch) | |
tree | 930cf3c912d3d91ea345a1fbfdc60e9c3131408f /firmware/test/memory/memory-slab.c | |
parent | 8a421390916414f37dd411aeff8748f3c1520bc2 (diff) | |
download | rockbox-e0ae9dc0081033be009d3e60b043e89e1e8d243f.tar.gz rockbox-e0ae9dc0081033be009d3e60b043e89e1e8d243f.zip |
Please don't try to compile them... they need to be fixed
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@118 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'firmware/test/memory/memory-slab.c')
-rw-r--r-- | firmware/test/memory/memory-slab.c | 450 |
1 files changed, 450 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..29dc609b47 --- /dev/null +++ b/firmware/test/memory/memory-slab.c | |||
@@ -0,0 +1,450 @@ | |||
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 | #ifndef __LIBRARY_MEMORY_C__ | ||
20 | # error "This header file must be included ONLY from memory.c." | ||
21 | #endif | ||
22 | #ifndef __LIBRARY_MEMORY_PAGE_H__ | ||
23 | # define __LIBRARY_MEMORY_PAGE_H__ | ||
24 | |||
25 | struct memory_free_block | ||
26 | { | ||
27 | struct memory_free_block | ||
28 | *link; | ||
29 | }; | ||
30 | |||
31 | /////////////////////////////////////////////////////////////////////////////// | ||
32 | // MEMORY SLAB : | ||
33 | //////////////// | ||
34 | // | ||
35 | // | ||
36 | |||
37 | struct memory_slab | ||
38 | { | ||
39 | struct memory_slab | ||
40 | *less,*more; | ||
41 | unsigned int // left == number of free blocks left | ||
42 | left; | ||
43 | struct memory_free_block | ||
44 | *free; | ||
45 | }; | ||
46 | |||
47 | static inline struct memory_slab *push_slab (struct memory_slab *head,struct memory_slab *node) | ||
48 | { | ||
49 | node->less = head; | ||
50 | if (head) | ||
51 | { | ||
52 | node->more = head->more; | ||
53 | head->more = node; | ||
54 | } | ||
55 | else | ||
56 | node->more = 0; | ||
57 | return node; | ||
58 | } | ||
59 | |||
60 | static inline struct memory_slab *pop_slab (struct memory_slab *head,struct memory_slab *node) | ||
61 | { | ||
62 | if (head) | ||
63 | head->more = node->more; | ||
64 | return node->more; | ||
65 | } | ||
66 | |||
67 | static inline struct memory_slab *move_slab (struct memory_slab **from,struct memory_slab **to) | ||
68 | { | ||
69 | struct memory_slab *head = *from; | ||
70 | *from = (*from)->more; | ||
71 | if (*from) | ||
72 | (*from)->less = head->less; | ||
73 | head->less = 0; | ||
74 | head->more = (*to); | ||
75 | if (*to) | ||
76 | (*to)->prev = head; | ||
77 | *to = head; | ||
78 | return head; | ||
79 | } | ||
80 | |||
81 | // | ||
82 | /////////////////////////////////////////////////////////////////////////////// | ||
83 | |||
84 | /////////////////////////////////////////////////////////////////////////////// | ||
85 | // MEMORY CACHE : | ||
86 | ///////////////// | ||
87 | // | ||
88 | // | ||
89 | |||
90 | struct memory_cache | ||
91 | { | ||
92 | struct memory_cache | ||
93 | *less,*more,*same; | ||
94 | unsigned int | ||
95 | left; // number of free slabs | ||
96 | struct memory_slab | ||
97 | *used; | ||
98 | struct memory_slab | ||
99 | *free; | ||
100 | struct memory_slab | ||
101 | *reap; | ||
102 | unsigned int | ||
103 | size,original_size; | ||
104 | unsigned int | ||
105 | page_size; | ||
106 | unsigned int | ||
107 | blocks_per_slab; | ||
108 | int | ||
109 | page_order; | ||
110 | unsigned int | ||
111 | flags; | ||
112 | }; | ||
113 | |||
114 | static struct memory_cache *cache_tree; | ||
115 | |||
116 | static inline int get_order (unsigned size) | ||
117 | { | ||
118 | int order = 0; | ||
119 | size = (size + sizeof(struct memory_free_block) - 1) & - sizeof(struct memory_free_block); | ||
120 | while (size > 0) | ||
121 | { | ||
122 | ++order; size <<= 1; | ||
123 | } | ||
124 | return order; | ||
125 | } | ||
126 | |||
127 | static inline struct memory_slab *get_slab (struct memory_cache *cache,void *address) | ||
128 | { | ||
129 | #ifdef TEST | ||
130 | return (struct memory_slab *)((((unsigned)address + cache->page_size) & -cache->page_size) - sizeof (struct memory_slab)); | ||
131 | #else | ||
132 | return (struct memory_slab *)((free_page + (((unsigned)address - free_page + cache->page_size) & -cache->page_size) - sizeof (struct memory_slab))); | ||
133 | #endif | ||
134 | } | ||
135 | |||
136 | static struct memory_cache *splay_cache (struct memory_cache *root,unsigned int left) | ||
137 | { | ||
138 | struct memory_cache *down; | ||
139 | struct memory_cache *less; | ||
140 | struct memory_cache *more; | ||
141 | struct memory_cache head; | ||
142 | head.less = | ||
143 | head.more = 0; | ||
144 | less = | ||
145 | more = &head; | ||
146 | while (1) | ||
147 | { | ||
148 | if (left < root->left) | ||
149 | { | ||
150 | if ((down = root->less)) | ||
151 | { | ||
152 | if (left < down->left) | ||
153 | { | ||
154 | root->less = down->more; | ||
155 | down->more = root; | ||
156 | root = down; | ||
157 | if (!root->less) | ||
158 | break; | ||
159 | } | ||
160 | more->less = root; | ||
161 | more = root; | ||
162 | root = root->less; | ||
163 | continue; | ||
164 | } | ||
165 | break; | ||
166 | } | ||
167 | if (root->left < left) | ||
168 | { | ||
169 | if ((down = root->more)) | ||
170 | { | ||
171 | if (root->left < left) | ||
172 | { | ||
173 | root->more = down->less; | ||
174 | down->less = root; | ||
175 | root = down; | ||
176 | if (!root->more) | ||
177 | break; | ||
178 | } | ||
179 | less->more = root; | ||
180 | less = root; | ||
181 | root = root->more; | ||
182 | continue; | ||
183 | } | ||
184 | } | ||
185 | break; | ||
186 | } | ||
187 | less->more = root->less; | ||
188 | more->less = root->more; | ||
189 | root->less = head.more; | ||
190 | root->more = head.less; | ||
191 | return root; | ||
192 | } | ||
193 | |||
194 | static inline struct memory_cache *insert_cache (struct memory_cache *root,struct memory_cache *node) | ||
195 | { | ||
196 | node->less = | ||
197 | node->more = | ||
198 | node->same = 0; | ||
199 | if (root) | ||
200 | { | ||
201 | if (node->left == ((root = splay_cache (root,node))->left)) | ||
202 | { | ||
203 | node->less = root.less; | ||
204 | node->more = root.more; | ||
205 | node->same = root; | ||
206 | root->less = node; | ||
207 | } | ||
208 | else if (node < root) | ||
209 | { | ||
210 | node->less = root->less; | ||
211 | node->more = root; | ||
212 | root->less = 0; | ||
213 | } | ||
214 | else | ||
215 | { | ||
216 | node->less = root; | ||
217 | node->more = root->more; | ||
218 | node->more = 0; | ||
219 | } | ||
220 | } | ||
221 | return node; | ||
222 | } | ||
223 | |||
224 | static inline struct memory_cache *remove_cache (struct memory_cache *root,struct memory_cache *node) | ||
225 | { | ||
226 | if (root) | ||
227 | { | ||
228 | root = splay_cache (root,node); | ||
229 | if (root != node) | ||
230 | { | ||
231 | node->less->same = node->same; | ||
232 | if (node->same) | ||
233 | node->same->less = node->less; | ||
234 | return root; | ||
235 | } | ||
236 | if (root->less) | ||
237 | { | ||
238 | node = splay_page (root->less,node); | ||
239 | node->more = root->more; | ||
240 | } | ||
241 | else | ||
242 | node = root->more; | ||
243 | } | ||
244 | return root; | ||
245 | } | ||
246 | |||
247 | static inline struct memory_cache *move_cache (struct memory_cache *root,struct memory_cache *node,int delta) | ||
248 | { | ||
249 | if ((root = remove_cache (root,node))) | ||
250 | { | ||
251 | node->left += delta; | ||
252 | root = insert_cache (root,node); | ||
253 | } | ||
254 | return root; | ||
255 | } | ||
256 | |||
257 | // | ||
258 | ///////////////////// | ||
259 | // PUBLIC FUNCTIONS : | ||
260 | ///////////////////// | ||
261 | // | ||
262 | // - memory_grow_cache : allocate a new slab for a cache | ||
263 | // - memory_shrink_cache : release free slabs from a cache | ||
264 | // - memory_create_cache : create a new cache of size-fixed blocks | ||
265 | // - memory_destroy_cache : destroy the cache and release all the slabs | ||
266 | // - memory_cache_allocate : allocate a block from the cache | ||
267 | // - memory_cache_release : release a block in the cache | ||
268 | // | ||
269 | |||
270 | struct memory_slab *memory_grow_cache (struct memory_cache *cache) | ||
271 | { | ||
272 | struct memory_slab *slab; | ||
273 | unsigned int page; | ||
274 | if (cache) | ||
275 | { | ||
276 | page = (unsigned int)memory_allocate_page (cache->page_order); | ||
277 | if (page) | ||
278 | { | ||
279 | struct memory_free_block *block,**link; | ||
280 | slab = (struct memory_slab *)(page + cache->page_size - sizeof (struct memory_slab)); | ||
281 | slab->free = 0; | ||
282 | slab->left = 0; | ||
283 | link = &slab->free; | ||
284 | for ((unsigned int)block = page; | ||
285 | (unsigned int)block + cache->size < (unsigned int)slab; | ||
286 | (unsigned int)block += cache->size) | ||
287 | { | ||
288 | *link = block; | ||
289 | link = &block->link; | ||
290 | ++slab->free; | ||
291 | } | ||
292 | *link = 0; | ||
293 | cache->blocks_per_slab = slab->free; | ||
294 | cache->reap = push_slab (cache->reap,slab); | ||
295 | cache_tree = move_cache (cache_tree,cache,+1); | ||
296 | return slab; | ||
297 | } | ||
298 | } | ||
299 | return MEMORY_RETURN_FAILURE; | ||
300 | } | ||
301 | |||
302 | static int shrink_cache (struct memory_cache *cache,int all,int move) | ||
303 | { | ||
304 | struct memory_slab *slab; | ||
305 | unsigned int slabs = 0; | ||
306 | if (cache) | ||
307 | { | ||
308 | while ((slab = cache->reap)) | ||
309 | { | ||
310 | ++slabs; | ||
311 | cache->reap = pop_slab (cache->reap,slab); | ||
312 | memory_release_page ((void *)slab); | ||
313 | if (all) | ||
314 | continue; | ||
315 | if (move) | ||
316 | cache_tree = move_cache (cache_tree,cache,-slabs); | ||
317 | return MEMORY_RETURN_SUCCESS; | ||
318 | } | ||
319 | } | ||
320 | return MEMORY_RETURN_FAILURE; | ||
321 | } | ||
322 | |||
323 | int memory_shrink_cache (struct memory_cache *cache,int all) | ||
324 | { | ||
325 | return shrink_cache (cache,all,1 /* move cache in cache_tree */); | ||
326 | } | ||
327 | |||
328 | struct memory_cache *memory_create_cache (unsigned int size,int align,int flags) | ||
329 | { | ||
330 | struct memory_cache *cache; | ||
331 | unsigned int waste = 0,blocks_per_page; | ||
332 | int page_order; | ||
333 | unsigned int page_size; | ||
334 | unsigned int original_size = size; | ||
335 | |||
336 | // Align size on 'align' bytes ('align' should equal 1<<n) | ||
337 | // if 'align' is inferior to 4, 32-bit word alignment is done by default. | ||
338 | size = (align > 4) ? ((size + align - 1) & -align) : ((size + sizeof (int) - 1) & -sizeof (int)); | ||
339 | if (!(cache = memory_cache_allocate (&cache_cache)) | ||
340 | return MEMORY_RETURN_FAILURE; | ||
341 | |||
342 | cache->flags = | ||
343 | cache->left = 0; | ||
344 | |||
345 | cache->used = | ||
346 | cache->free = | ||
347 | cache->reap = 0; | ||
348 | |||
349 | cache->original_size = original_size; | ||
350 | cache->size = size; | ||
351 | |||
352 | page_size = 0; | ||
353 | page_order = MEMORY_PAGE_MINIMAL_SIZE;; | ||
354 | |||
355 | // Trying to determine what is the best number of pages per slab | ||
356 | for (;; ++order,(page_size <<= 1)) | ||
357 | { | ||
358 | if (page_order >= MEMORY_MAXIMUM_PAGE_ORDER_PER_SLAB) | ||
359 | { | ||
360 | memory_cache_release (&cache_cache,cache); | ||
361 | return MEMORY_RETURN_FAILURE; | ||
362 | } | ||
363 | |||
364 | waste = page_size; | ||
365 | waste -= sizeof (struct memory_slab); | ||
366 | |||
367 | blocks_per_slab = waste / size; | ||
368 | waste -= block_per_slab * size; | ||
369 | |||
370 | if (blocks_per_slab < MEMORY_MINIMUM_BLOCKS_PER_SLAB) | ||
371 | { | ||
372 | ++page_order; page_size <<= 1; | ||
373 | continue; | ||
374 | } | ||
375 | |||
376 | // below 3% of lost space is correct | ||
377 | if ((waste << 16) / page_size) < 1967) | ||
378 | break; | ||
379 | ++page_order; page_size <<= 1; | ||
380 | } | ||
381 | |||
382 | cache->page_size = page_size; | ||
383 | cache->page_order = page_order; | ||
384 | |||
385 | cache_tree = insert_cache (cache_tree,cache); | ||
386 | |||
387 | return cache; | ||
388 | } | ||
389 | |||
390 | int memory_destroy_cache (struct memory_cache *cache) | ||
391 | { | ||
392 | /* FIX ME : this function shouldn't be called if there are still used blocks */ | ||
393 | if (cache && !cache->free && !cache->used) | ||
394 | { | ||
395 | cache_tree = remove_cache (cache_tree,cache); | ||
396 | if (shrink_cache (cache,1 /* release all free slabs */,0 /* don't move in cache_tree */)) | ||
397 | return memory_cache_release (&cache_cache,cache); | ||
398 | } | ||
399 | return MEMORY_RETURN_FAILURE; | ||
400 | } | ||
401 | |||
402 | void *memory_cache_allocate (struct memory_cache *cache) | ||
403 | { | ||
404 | if (cache) | ||
405 | { | ||
406 | do | ||
407 | { | ||
408 | struct memory_slab *slab; | ||
409 | if ((slab = cache->free)) | ||
410 | { | ||
411 | if (slab->left > 0) | ||
412 | { | ||
413 | ok: struct memory_free_block *block = slab->free; | ||
414 | slab->free = block->link; | ||
415 | if (--slab->left == 0) | ||
416 | move_slab (&cache->free,&cache->used); | ||
417 | return block; | ||
418 | } | ||
419 | } | ||
420 | if (cache->reap) | ||
421 | { | ||
422 | slab = move_slab (&cache->reap,&cache->free); | ||
423 | cache_tree = move_cache (cache_tree,cache,-1); | ||
424 | goto ok; | ||
425 | } | ||
426 | } | ||
427 | while (grow_cache (cache)); | ||
428 | } | ||
429 | return MEMORY_RETURN_FAILURE; | ||
430 | } | ||
431 | |||
432 | int memory_cache_release (struct memory_cache *cache,void *address) | ||
433 | { | ||
434 | struct memory_slab *slab = get_slab (cache,address); | ||
435 | ((struct memory_free_block *)address)->link = slab->free; | ||
436 | slab->free = (struct memory_free_block *)address; | ||
437 | if (slab->left++ == 0) | ||
438 | move_slab (&cache->used,&cache->free); | ||
439 | else if (slab->left == cache->blocks_per_slab) | ||
440 | { | ||
441 | move_slab (&cache->free,&cache->reap); | ||
442 | cache_tree = move_cache (cache_tree,cache,+1); | ||
443 | } | ||
444 | return MEMORY_RETURN_SUCCESS; | ||
445 | } | ||
446 | |||
447 | // | ||
448 | /////////////////////////////////////////////////////////////////////////////// | ||
449 | |||
450 | #endif | ||