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Commit | Line | Data |
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10cef602 MM |
1 | /* |
2 | * SLOB Allocator: Simple List Of Blocks | |
3 | * | |
4 | * Matt Mackall <mpm@selenic.com> 12/30/03 | |
5 | * | |
6193a2ff PM |
6 | * NUMA support by Paul Mundt, 2007. |
7 | * | |
10cef602 MM |
8 | * How SLOB works: |
9 | * | |
10 | * The core of SLOB is a traditional K&R style heap allocator, with | |
11 | * support for returning aligned objects. The granularity of this | |
55394849 NP |
12 | * allocator is as little as 2 bytes, however typically most architectures |
13 | * will require 4 bytes on 32-bit and 8 bytes on 64-bit. | |
95b35127 | 14 | * |
6193a2ff | 15 | * The slob heap is a linked list of pages from alloc_pages(), and |
95b35127 NP |
16 | * within each page, there is a singly-linked list of free blocks (slob_t). |
17 | * The heap is grown on demand and allocation from the heap is currently | |
18 | * first-fit. | |
10cef602 MM |
19 | * |
20 | * Above this is an implementation of kmalloc/kfree. Blocks returned | |
55394849 | 21 | * from kmalloc are prepended with a 4-byte header with the kmalloc size. |
10cef602 | 22 | * If kmalloc is asked for objects of PAGE_SIZE or larger, it calls |
6193a2ff | 23 | * alloc_pages() directly, allocating compound pages so the page order |
d87a133f NP |
24 | * does not have to be separately tracked, and also stores the exact |
25 | * allocation size in page->private so that it can be used to accurately | |
26 | * provide ksize(). These objects are detected in kfree() because slob_page() | |
27 | * is false for them. | |
10cef602 MM |
28 | * |
29 | * SLAB is emulated on top of SLOB by simply calling constructors and | |
95b35127 NP |
30 | * destructors for every SLAB allocation. Objects are returned with the |
31 | * 4-byte alignment unless the SLAB_HWCACHE_ALIGN flag is set, in which | |
32 | * case the low-level allocator will fragment blocks to create the proper | |
33 | * alignment. Again, objects of page-size or greater are allocated by | |
6193a2ff | 34 | * calling alloc_pages(). As SLAB objects know their size, no separate |
95b35127 | 35 | * size bookkeeping is necessary and there is essentially no allocation |
d87a133f NP |
36 | * space overhead, and compound pages aren't needed for multi-page |
37 | * allocations. | |
6193a2ff PM |
38 | * |
39 | * NUMA support in SLOB is fairly simplistic, pushing most of the real | |
40 | * logic down to the page allocator, and simply doing the node accounting | |
41 | * on the upper levels. In the event that a node id is explicitly | |
42 | * provided, alloc_pages_node() with the specified node id is used | |
43 | * instead. The common case (or when the node id isn't explicitly provided) | |
44 | * will default to the current node, as per numa_node_id(). | |
45 | * | |
46 | * Node aware pages are still inserted in to the global freelist, and | |
47 | * these are scanned for by matching against the node id encoded in the | |
48 | * page flags. As a result, block allocations that can be satisfied from | |
49 | * the freelist will only be done so on pages residing on the same node, | |
50 | * in order to prevent random node placement. | |
10cef602 MM |
51 | */ |
52 | ||
95b35127 | 53 | #include <linux/kernel.h> |
10cef602 MM |
54 | #include <linux/slab.h> |
55 | #include <linux/mm.h> | |
56 | #include <linux/cache.h> | |
57 | #include <linux/init.h> | |
58 | #include <linux/module.h> | |
afc0cedb | 59 | #include <linux/rcupdate.h> |
95b35127 NP |
60 | #include <linux/list.h> |
61 | #include <asm/atomic.h> | |
62 | ||
95b35127 NP |
63 | /* |
64 | * slob_block has a field 'units', which indicates size of block if +ve, | |
65 | * or offset of next block if -ve (in SLOB_UNITs). | |
66 | * | |
67 | * Free blocks of size 1 unit simply contain the offset of the next block. | |
68 | * Those with larger size contain their size in the first SLOB_UNIT of | |
69 | * memory, and the offset of the next free block in the second SLOB_UNIT. | |
70 | */ | |
55394849 | 71 | #if PAGE_SIZE <= (32767 * 2) |
95b35127 NP |
72 | typedef s16 slobidx_t; |
73 | #else | |
74 | typedef s32 slobidx_t; | |
75 | #endif | |
76 | ||
10cef602 | 77 | struct slob_block { |
95b35127 | 78 | slobidx_t units; |
55394849 | 79 | }; |
10cef602 MM |
80 | typedef struct slob_block slob_t; |
81 | ||
95b35127 NP |
82 | /* |
83 | * We use struct page fields to manage some slob allocation aspects, | |
84 | * however to avoid the horrible mess in include/linux/mm_types.h, we'll | |
85 | * just define our own struct page type variant here. | |
86 | */ | |
87 | struct slob_page { | |
88 | union { | |
89 | struct { | |
90 | unsigned long flags; /* mandatory */ | |
91 | atomic_t _count; /* mandatory */ | |
92 | slobidx_t units; /* free units left in page */ | |
93 | unsigned long pad[2]; | |
94 | slob_t *free; /* first free slob_t in page */ | |
95 | struct list_head list; /* linked list of free pages */ | |
96 | }; | |
97 | struct page page; | |
98 | }; | |
99 | }; | |
100 | static inline void struct_slob_page_wrong_size(void) | |
101 | { BUILD_BUG_ON(sizeof(struct slob_page) != sizeof(struct page)); } | |
102 | ||
103 | /* | |
104 | * free_slob_page: call before a slob_page is returned to the page allocator. | |
105 | */ | |
106 | static inline void free_slob_page(struct slob_page *sp) | |
107 | { | |
108 | reset_page_mapcount(&sp->page); | |
109 | sp->page.mapping = NULL; | |
110 | } | |
111 | ||
112 | /* | |
113 | * All (partially) free slob pages go on this list. | |
114 | */ | |
115 | static LIST_HEAD(free_slob_pages); | |
116 | ||
117 | /* | |
118 | * slob_page: True for all slob pages (false for bigblock pages) | |
119 | */ | |
120 | static inline int slob_page(struct slob_page *sp) | |
121 | { | |
122 | return test_bit(PG_active, &sp->flags); | |
123 | } | |
124 | ||
125 | static inline void set_slob_page(struct slob_page *sp) | |
126 | { | |
127 | __set_bit(PG_active, &sp->flags); | |
128 | } | |
129 | ||
130 | static inline void clear_slob_page(struct slob_page *sp) | |
131 | { | |
132 | __clear_bit(PG_active, &sp->flags); | |
133 | } | |
134 | ||
135 | /* | |
136 | * slob_page_free: true for pages on free_slob_pages list. | |
137 | */ | |
138 | static inline int slob_page_free(struct slob_page *sp) | |
139 | { | |
140 | return test_bit(PG_private, &sp->flags); | |
141 | } | |
142 | ||
143 | static inline void set_slob_page_free(struct slob_page *sp) | |
144 | { | |
145 | list_add(&sp->list, &free_slob_pages); | |
146 | __set_bit(PG_private, &sp->flags); | |
147 | } | |
148 | ||
149 | static inline void clear_slob_page_free(struct slob_page *sp) | |
150 | { | |
151 | list_del(&sp->list); | |
152 | __clear_bit(PG_private, &sp->flags); | |
153 | } | |
154 | ||
10cef602 MM |
155 | #define SLOB_UNIT sizeof(slob_t) |
156 | #define SLOB_UNITS(size) (((size) + SLOB_UNIT - 1)/SLOB_UNIT) | |
157 | #define SLOB_ALIGN L1_CACHE_BYTES | |
158 | ||
afc0cedb NP |
159 | /* |
160 | * struct slob_rcu is inserted at the tail of allocated slob blocks, which | |
161 | * were created with a SLAB_DESTROY_BY_RCU slab. slob_rcu is used to free | |
162 | * the block using call_rcu. | |
163 | */ | |
164 | struct slob_rcu { | |
165 | struct rcu_head head; | |
166 | int size; | |
167 | }; | |
168 | ||
95b35127 NP |
169 | /* |
170 | * slob_lock protects all slob allocator structures. | |
171 | */ | |
10cef602 | 172 | static DEFINE_SPINLOCK(slob_lock); |
10cef602 | 173 | |
95b35127 NP |
174 | /* |
175 | * Encode the given size and next info into a free slob block s. | |
176 | */ | |
177 | static void set_slob(slob_t *s, slobidx_t size, slob_t *next) | |
178 | { | |
179 | slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); | |
180 | slobidx_t offset = next - base; | |
bcb4ddb4 | 181 | |
95b35127 NP |
182 | if (size > 1) { |
183 | s[0].units = size; | |
184 | s[1].units = offset; | |
185 | } else | |
186 | s[0].units = -offset; | |
187 | } | |
10cef602 | 188 | |
95b35127 NP |
189 | /* |
190 | * Return the size of a slob block. | |
191 | */ | |
192 | static slobidx_t slob_units(slob_t *s) | |
193 | { | |
194 | if (s->units > 0) | |
195 | return s->units; | |
196 | return 1; | |
197 | } | |
198 | ||
199 | /* | |
200 | * Return the next free slob block pointer after this one. | |
201 | */ | |
202 | static slob_t *slob_next(slob_t *s) | |
203 | { | |
204 | slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); | |
205 | slobidx_t next; | |
206 | ||
207 | if (s[0].units < 0) | |
208 | next = -s[0].units; | |
209 | else | |
210 | next = s[1].units; | |
211 | return base+next; | |
212 | } | |
213 | ||
214 | /* | |
215 | * Returns true if s is the last free block in its page. | |
216 | */ | |
217 | static int slob_last(slob_t *s) | |
218 | { | |
219 | return !((unsigned long)slob_next(s) & ~PAGE_MASK); | |
220 | } | |
221 | ||
6193a2ff PM |
222 | static void *slob_new_page(gfp_t gfp, int order, int node) |
223 | { | |
224 | void *page; | |
225 | ||
226 | #ifdef CONFIG_NUMA | |
227 | if (node != -1) | |
228 | page = alloc_pages_node(node, gfp, order); | |
229 | else | |
230 | #endif | |
231 | page = alloc_pages(gfp, order); | |
232 | ||
233 | if (!page) | |
234 | return NULL; | |
235 | ||
236 | return page_address(page); | |
237 | } | |
238 | ||
95b35127 NP |
239 | /* |
240 | * Allocate a slob block within a given slob_page sp. | |
241 | */ | |
242 | static void *slob_page_alloc(struct slob_page *sp, size_t size, int align) | |
10cef602 MM |
243 | { |
244 | slob_t *prev, *cur, *aligned = 0; | |
245 | int delta = 0, units = SLOB_UNITS(size); | |
10cef602 | 246 | |
95b35127 NP |
247 | for (prev = NULL, cur = sp->free; ; prev = cur, cur = slob_next(cur)) { |
248 | slobidx_t avail = slob_units(cur); | |
249 | ||
10cef602 MM |
250 | if (align) { |
251 | aligned = (slob_t *)ALIGN((unsigned long)cur, align); | |
252 | delta = aligned - cur; | |
253 | } | |
95b35127 NP |
254 | if (avail >= units + delta) { /* room enough? */ |
255 | slob_t *next; | |
256 | ||
10cef602 | 257 | if (delta) { /* need to fragment head to align? */ |
95b35127 NP |
258 | next = slob_next(cur); |
259 | set_slob(aligned, avail - delta, next); | |
260 | set_slob(cur, delta, aligned); | |
10cef602 MM |
261 | prev = cur; |
262 | cur = aligned; | |
95b35127 | 263 | avail = slob_units(cur); |
10cef602 MM |
264 | } |
265 | ||
95b35127 NP |
266 | next = slob_next(cur); |
267 | if (avail == units) { /* exact fit? unlink. */ | |
268 | if (prev) | |
269 | set_slob(prev, slob_units(prev), next); | |
270 | else | |
271 | sp->free = next; | |
272 | } else { /* fragment */ | |
273 | if (prev) | |
274 | set_slob(prev, slob_units(prev), cur + units); | |
275 | else | |
276 | sp->free = cur + units; | |
277 | set_slob(cur + units, avail - units, next); | |
10cef602 MM |
278 | } |
279 | ||
95b35127 NP |
280 | sp->units -= units; |
281 | if (!sp->units) | |
282 | clear_slob_page_free(sp); | |
10cef602 MM |
283 | return cur; |
284 | } | |
95b35127 NP |
285 | if (slob_last(cur)) |
286 | return NULL; | |
287 | } | |
288 | } | |
10cef602 | 289 | |
95b35127 NP |
290 | /* |
291 | * slob_alloc: entry point into the slob allocator. | |
292 | */ | |
6193a2ff | 293 | static void *slob_alloc(size_t size, gfp_t gfp, int align, int node) |
95b35127 NP |
294 | { |
295 | struct slob_page *sp; | |
d6269543 | 296 | struct list_head *prev; |
95b35127 NP |
297 | slob_t *b = NULL; |
298 | unsigned long flags; | |
10cef602 | 299 | |
95b35127 NP |
300 | spin_lock_irqsave(&slob_lock, flags); |
301 | /* Iterate through each partially free page, try to find room */ | |
302 | list_for_each_entry(sp, &free_slob_pages, list) { | |
6193a2ff PM |
303 | #ifdef CONFIG_NUMA |
304 | /* | |
305 | * If there's a node specification, search for a partial | |
306 | * page with a matching node id in the freelist. | |
307 | */ | |
308 | if (node != -1 && page_to_nid(&sp->page) != node) | |
309 | continue; | |
310 | #endif | |
d6269543 MM |
311 | /* Enough room on this page? */ |
312 | if (sp->units < SLOB_UNITS(size)) | |
313 | continue; | |
6193a2ff | 314 | |
d6269543 MM |
315 | /* Attempt to alloc */ |
316 | prev = sp->list.prev; | |
317 | b = slob_page_alloc(sp, size, align); | |
318 | if (!b) | |
319 | continue; | |
320 | ||
321 | /* Improve fragment distribution and reduce our average | |
322 | * search time by starting our next search here. (see | |
323 | * Knuth vol 1, sec 2.5, pg 449) */ | |
d32ddd8f NP |
324 | if (prev != free_slob_pages.prev && |
325 | free_slob_pages.next != prev->next) | |
d6269543 MM |
326 | list_move_tail(&free_slob_pages, prev->next); |
327 | break; | |
10cef602 | 328 | } |
95b35127 NP |
329 | spin_unlock_irqrestore(&slob_lock, flags); |
330 | ||
331 | /* Not enough space: must allocate a new page */ | |
332 | if (!b) { | |
7fd27255 | 333 | b = slob_new_page(gfp & ~__GFP_ZERO, 0, node); |
95b35127 NP |
334 | if (!b) |
335 | return 0; | |
336 | sp = (struct slob_page *)virt_to_page(b); | |
337 | set_slob_page(sp); | |
338 | ||
339 | spin_lock_irqsave(&slob_lock, flags); | |
340 | sp->units = SLOB_UNITS(PAGE_SIZE); | |
341 | sp->free = b; | |
342 | INIT_LIST_HEAD(&sp->list); | |
343 | set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE)); | |
344 | set_slob_page_free(sp); | |
345 | b = slob_page_alloc(sp, size, align); | |
346 | BUG_ON(!b); | |
347 | spin_unlock_irqrestore(&slob_lock, flags); | |
348 | } | |
d07dbea4 CL |
349 | if (unlikely((gfp & __GFP_ZERO) && b)) |
350 | memset(b, 0, size); | |
95b35127 | 351 | return b; |
10cef602 MM |
352 | } |
353 | ||
95b35127 NP |
354 | /* |
355 | * slob_free: entry point into the slob allocator. | |
356 | */ | |
10cef602 MM |
357 | static void slob_free(void *block, int size) |
358 | { | |
95b35127 NP |
359 | struct slob_page *sp; |
360 | slob_t *prev, *next, *b = (slob_t *)block; | |
361 | slobidx_t units; | |
10cef602 MM |
362 | unsigned long flags; |
363 | ||
2408c550 | 364 | if (unlikely(ZERO_OR_NULL_PTR(block))) |
10cef602 | 365 | return; |
95b35127 | 366 | BUG_ON(!size); |
10cef602 | 367 | |
95b35127 NP |
368 | sp = (struct slob_page *)virt_to_page(block); |
369 | units = SLOB_UNITS(size); | |
10cef602 | 370 | |
10cef602 | 371 | spin_lock_irqsave(&slob_lock, flags); |
10cef602 | 372 | |
95b35127 NP |
373 | if (sp->units + units == SLOB_UNITS(PAGE_SIZE)) { |
374 | /* Go directly to page allocator. Do not pass slob allocator */ | |
375 | if (slob_page_free(sp)) | |
376 | clear_slob_page_free(sp); | |
377 | clear_slob_page(sp); | |
378 | free_slob_page(sp); | |
379 | free_page((unsigned long)b); | |
380 | goto out; | |
381 | } | |
10cef602 | 382 | |
95b35127 NP |
383 | if (!slob_page_free(sp)) { |
384 | /* This slob page is about to become partially free. Easy! */ | |
385 | sp->units = units; | |
386 | sp->free = b; | |
387 | set_slob(b, units, | |
388 | (void *)((unsigned long)(b + | |
389 | SLOB_UNITS(PAGE_SIZE)) & PAGE_MASK)); | |
390 | set_slob_page_free(sp); | |
391 | goto out; | |
392 | } | |
393 | ||
394 | /* | |
395 | * Otherwise the page is already partially free, so find reinsertion | |
396 | * point. | |
397 | */ | |
398 | sp->units += units; | |
10cef602 | 399 | |
95b35127 NP |
400 | if (b < sp->free) { |
401 | set_slob(b, units, sp->free); | |
402 | sp->free = b; | |
403 | } else { | |
404 | prev = sp->free; | |
405 | next = slob_next(prev); | |
406 | while (b > next) { | |
407 | prev = next; | |
408 | next = slob_next(prev); | |
409 | } | |
10cef602 | 410 | |
95b35127 NP |
411 | if (!slob_last(prev) && b + units == next) { |
412 | units += slob_units(next); | |
413 | set_slob(b, units, slob_next(next)); | |
414 | } else | |
415 | set_slob(b, units, next); | |
416 | ||
417 | if (prev + slob_units(prev) == b) { | |
418 | units = slob_units(b) + slob_units(prev); | |
419 | set_slob(prev, units, slob_next(b)); | |
420 | } else | |
421 | set_slob(prev, slob_units(prev), b); | |
422 | } | |
423 | out: | |
10cef602 MM |
424 | spin_unlock_irqrestore(&slob_lock, flags); |
425 | } | |
426 | ||
95b35127 NP |
427 | /* |
428 | * End of slob allocator proper. Begin kmem_cache_alloc and kmalloc frontend. | |
429 | */ | |
430 | ||
55394849 NP |
431 | #ifndef ARCH_KMALLOC_MINALIGN |
432 | #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long) | |
433 | #endif | |
434 | ||
435 | #ifndef ARCH_SLAB_MINALIGN | |
436 | #define ARCH_SLAB_MINALIGN __alignof__(unsigned long) | |
437 | #endif | |
438 | ||
6193a2ff | 439 | void *__kmalloc_node(size_t size, gfp_t gfp, int node) |
10cef602 | 440 | { |
6cb8f913 | 441 | unsigned int *m; |
55394849 NP |
442 | int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN); |
443 | ||
444 | if (size < PAGE_SIZE - align) { | |
6cb8f913 CL |
445 | if (!size) |
446 | return ZERO_SIZE_PTR; | |
447 | ||
6193a2ff | 448 | m = slob_alloc(size + align, gfp, align, node); |
95b35127 | 449 | if (m) |
55394849 NP |
450 | *m = size; |
451 | return (void *)m + align; | |
d87a133f NP |
452 | } else { |
453 | void *ret; | |
454 | ||
6193a2ff | 455 | ret = slob_new_page(gfp | __GFP_COMP, get_order(size), node); |
d87a133f NP |
456 | if (ret) { |
457 | struct page *page; | |
458 | page = virt_to_page(ret); | |
459 | page->private = size; | |
460 | } | |
461 | return ret; | |
10cef602 | 462 | } |
10cef602 | 463 | } |
6193a2ff | 464 | EXPORT_SYMBOL(__kmalloc_node); |
10cef602 MM |
465 | |
466 | void kfree(const void *block) | |
467 | { | |
95b35127 | 468 | struct slob_page *sp; |
10cef602 | 469 | |
2408c550 | 470 | if (unlikely(ZERO_OR_NULL_PTR(block))) |
10cef602 MM |
471 | return; |
472 | ||
95b35127 | 473 | sp = (struct slob_page *)virt_to_page(block); |
d87a133f | 474 | if (slob_page(sp)) { |
55394849 NP |
475 | int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN); |
476 | unsigned int *m = (unsigned int *)(block - align); | |
477 | slob_free(m, *m + align); | |
d87a133f NP |
478 | } else |
479 | put_page(&sp->page); | |
10cef602 | 480 | } |
10cef602 MM |
481 | EXPORT_SYMBOL(kfree); |
482 | ||
d87a133f | 483 | /* can't use ksize for kmem_cache_alloc memory, only kmalloc */ |
fd76bab2 | 484 | size_t ksize(const void *block) |
10cef602 | 485 | { |
95b35127 | 486 | struct slob_page *sp; |
10cef602 | 487 | |
ef8b4520 CL |
488 | BUG_ON(!block); |
489 | if (unlikely(block == ZERO_SIZE_PTR)) | |
10cef602 MM |
490 | return 0; |
491 | ||
95b35127 | 492 | sp = (struct slob_page *)virt_to_page(block); |
d87a133f NP |
493 | if (slob_page(sp)) |
494 | return ((slob_t *)block - 1)->units + SLOB_UNIT; | |
495 | else | |
496 | return sp->page.private; | |
10cef602 | 497 | } |
f8fcc933 | 498 | EXPORT_SYMBOL(ksize); |
10cef602 MM |
499 | |
500 | struct kmem_cache { | |
501 | unsigned int size, align; | |
afc0cedb | 502 | unsigned long flags; |
10cef602 | 503 | const char *name; |
4ba9b9d0 | 504 | void (*ctor)(struct kmem_cache *, void *); |
10cef602 MM |
505 | }; |
506 | ||
507 | struct kmem_cache *kmem_cache_create(const char *name, size_t size, | |
508 | size_t align, unsigned long flags, | |
4ba9b9d0 | 509 | void (*ctor)(struct kmem_cache *, void *)) |
10cef602 MM |
510 | { |
511 | struct kmem_cache *c; | |
512 | ||
6193a2ff | 513 | c = slob_alloc(sizeof(struct kmem_cache), flags, 0, -1); |
10cef602 MM |
514 | |
515 | if (c) { | |
516 | c->name = name; | |
517 | c->size = size; | |
afc0cedb | 518 | if (flags & SLAB_DESTROY_BY_RCU) { |
afc0cedb NP |
519 | /* leave room for rcu footer at the end of object */ |
520 | c->size += sizeof(struct slob_rcu); | |
521 | } | |
522 | c->flags = flags; | |
10cef602 | 523 | c->ctor = ctor; |
10cef602 | 524 | /* ignore alignment unless it's forced */ |
5af60839 | 525 | c->align = (flags & SLAB_HWCACHE_ALIGN) ? SLOB_ALIGN : 0; |
55394849 NP |
526 | if (c->align < ARCH_SLAB_MINALIGN) |
527 | c->align = ARCH_SLAB_MINALIGN; | |
10cef602 MM |
528 | if (c->align < align) |
529 | c->align = align; | |
bc0055ae AM |
530 | } else if (flags & SLAB_PANIC) |
531 | panic("Cannot create slab cache %s\n", name); | |
10cef602 MM |
532 | |
533 | return c; | |
534 | } | |
535 | EXPORT_SYMBOL(kmem_cache_create); | |
536 | ||
133d205a | 537 | void kmem_cache_destroy(struct kmem_cache *c) |
10cef602 MM |
538 | { |
539 | slob_free(c, sizeof(struct kmem_cache)); | |
10cef602 MM |
540 | } |
541 | EXPORT_SYMBOL(kmem_cache_destroy); | |
542 | ||
6193a2ff | 543 | void *kmem_cache_alloc_node(struct kmem_cache *c, gfp_t flags, int node) |
10cef602 MM |
544 | { |
545 | void *b; | |
546 | ||
547 | if (c->size < PAGE_SIZE) | |
6193a2ff | 548 | b = slob_alloc(c->size, flags, c->align, node); |
10cef602 | 549 | else |
6193a2ff | 550 | b = slob_new_page(flags, get_order(c->size), node); |
10cef602 MM |
551 | |
552 | if (c->ctor) | |
4ba9b9d0 | 553 | c->ctor(c, b); |
10cef602 MM |
554 | |
555 | return b; | |
556 | } | |
6193a2ff | 557 | EXPORT_SYMBOL(kmem_cache_alloc_node); |
10cef602 | 558 | |
afc0cedb | 559 | static void __kmem_cache_free(void *b, int size) |
10cef602 | 560 | { |
afc0cedb NP |
561 | if (size < PAGE_SIZE) |
562 | slob_free(b, size); | |
10cef602 | 563 | else |
afc0cedb NP |
564 | free_pages((unsigned long)b, get_order(size)); |
565 | } | |
566 | ||
567 | static void kmem_rcu_free(struct rcu_head *head) | |
568 | { | |
569 | struct slob_rcu *slob_rcu = (struct slob_rcu *)head; | |
570 | void *b = (void *)slob_rcu - (slob_rcu->size - sizeof(struct slob_rcu)); | |
571 | ||
572 | __kmem_cache_free(b, slob_rcu->size); | |
573 | } | |
574 | ||
575 | void kmem_cache_free(struct kmem_cache *c, void *b) | |
576 | { | |
577 | if (unlikely(c->flags & SLAB_DESTROY_BY_RCU)) { | |
578 | struct slob_rcu *slob_rcu; | |
579 | slob_rcu = b + (c->size - sizeof(struct slob_rcu)); | |
580 | INIT_RCU_HEAD(&slob_rcu->head); | |
581 | slob_rcu->size = c->size; | |
582 | call_rcu(&slob_rcu->head, kmem_rcu_free); | |
583 | } else { | |
afc0cedb NP |
584 | __kmem_cache_free(b, c->size); |
585 | } | |
10cef602 MM |
586 | } |
587 | EXPORT_SYMBOL(kmem_cache_free); | |
588 | ||
589 | unsigned int kmem_cache_size(struct kmem_cache *c) | |
590 | { | |
591 | return c->size; | |
592 | } | |
593 | EXPORT_SYMBOL(kmem_cache_size); | |
594 | ||
595 | const char *kmem_cache_name(struct kmem_cache *c) | |
596 | { | |
597 | return c->name; | |
598 | } | |
599 | EXPORT_SYMBOL(kmem_cache_name); | |
600 | ||
2e892f43 CL |
601 | int kmem_cache_shrink(struct kmem_cache *d) |
602 | { | |
603 | return 0; | |
604 | } | |
605 | EXPORT_SYMBOL(kmem_cache_shrink); | |
606 | ||
55935a34 | 607 | int kmem_ptr_validate(struct kmem_cache *a, const void *b) |
2e892f43 CL |
608 | { |
609 | return 0; | |
610 | } | |
611 | ||
84a01c2f PM |
612 | static unsigned int slob_ready __read_mostly; |
613 | ||
614 | int slab_is_available(void) | |
615 | { | |
616 | return slob_ready; | |
617 | } | |
618 | ||
bcb4ddb4 DG |
619 | void __init kmem_cache_init(void) |
620 | { | |
84a01c2f | 621 | slob_ready = 1; |
10cef602 | 622 | } |