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1 | // SPDX-License-Identifier: GPL-2.0 | |
2 | /* | |
3 | * SLOB Allocator: Simple List Of Blocks | |
4 | * | |
5 | * Matt Mackall <mpm@selenic.com> 12/30/03 | |
6 | * | |
7 | * NUMA support by Paul Mundt, 2007. | |
8 | * | |
9 | * How SLOB works: | |
10 | * | |
11 | * The core of SLOB is a traditional K&R style heap allocator, with | |
12 | * support for returning aligned objects. The granularity of this | |
13 | * allocator is as little as 2 bytes, however typically most architectures | |
14 | * will require 4 bytes on 32-bit and 8 bytes on 64-bit. | |
15 | * | |
16 | * The slob heap is a set of linked list of pages from alloc_pages(), | |
17 | * and within each page, there is a singly-linked list of free blocks | |
18 | * (slob_t). The heap is grown on demand. To reduce fragmentation, | |
19 | * heap pages are segregated into three lists, with objects less than | |
20 | * 256 bytes, objects less than 1024 bytes, and all other objects. | |
21 | * | |
22 | * Allocation from heap involves first searching for a page with | |
23 | * sufficient free blocks (using a next-fit-like approach) followed by | |
24 | * a first-fit scan of the page. Deallocation inserts objects back | |
25 | * into the free list in address order, so this is effectively an | |
26 | * address-ordered first fit. | |
27 | * | |
28 | * Above this is an implementation of kmalloc/kfree. Blocks returned | |
29 | * from kmalloc are prepended with a 4-byte header with the kmalloc size. | |
30 | * If kmalloc is asked for objects of PAGE_SIZE or larger, it calls | |
31 | * alloc_pages() directly, allocating compound pages so the page order | |
32 | * does not have to be separately tracked. | |
33 | * These objects are detected in kfree() because PageSlab() | |
34 | * is false for them. | |
35 | * | |
36 | * SLAB is emulated on top of SLOB by simply calling constructors and | |
37 | * destructors for every SLAB allocation. Objects are returned with the | |
38 | * 4-byte alignment unless the SLAB_HWCACHE_ALIGN flag is set, in which | |
39 | * case the low-level allocator will fragment blocks to create the proper | |
40 | * alignment. Again, objects of page-size or greater are allocated by | |
41 | * calling alloc_pages(). As SLAB objects know their size, no separate | |
42 | * size bookkeeping is necessary and there is essentially no allocation | |
43 | * space overhead, and compound pages aren't needed for multi-page | |
44 | * allocations. | |
45 | * | |
46 | * NUMA support in SLOB is fairly simplistic, pushing most of the real | |
47 | * logic down to the page allocator, and simply doing the node accounting | |
48 | * on the upper levels. In the event that a node id is explicitly | |
49 | * provided, __alloc_pages_node() with the specified node id is used | |
50 | * instead. The common case (or when the node id isn't explicitly provided) | |
51 | * will default to the current node, as per numa_node_id(). | |
52 | * | |
53 | * Node aware pages are still inserted in to the global freelist, and | |
54 | * these are scanned for by matching against the node id encoded in the | |
55 | * page flags. As a result, block allocations that can be satisfied from | |
56 | * the freelist will only be done so on pages residing on the same node, | |
57 | * in order to prevent random node placement. | |
58 | */ | |
59 | ||
60 | #include <linux/kernel.h> | |
61 | #include <linux/slab.h> | |
62 | ||
63 | #include <linux/mm.h> | |
64 | #include <linux/swap.h> /* struct reclaim_state */ | |
65 | #include <linux/cache.h> | |
66 | #include <linux/init.h> | |
67 | #include <linux/export.h> | |
68 | #include <linux/rcupdate.h> | |
69 | #include <linux/list.h> | |
70 | #include <linux/kmemleak.h> | |
71 | ||
72 | #include <trace/events/kmem.h> | |
73 | ||
74 | #include <linux/atomic.h> | |
75 | ||
76 | #include "slab.h" | |
77 | /* | |
78 | * slob_block has a field 'units', which indicates size of block if +ve, | |
79 | * or offset of next block if -ve (in SLOB_UNITs). | |
80 | * | |
81 | * Free blocks of size 1 unit simply contain the offset of the next block. | |
82 | * Those with larger size contain their size in the first SLOB_UNIT of | |
83 | * memory, and the offset of the next free block in the second SLOB_UNIT. | |
84 | */ | |
85 | #if PAGE_SIZE <= (32767 * 2) | |
86 | typedef s16 slobidx_t; | |
87 | #else | |
88 | typedef s32 slobidx_t; | |
89 | #endif | |
90 | ||
91 | struct slob_block { | |
92 | slobidx_t units; | |
93 | }; | |
94 | typedef struct slob_block slob_t; | |
95 | ||
96 | /* | |
97 | * All partially free slob pages go on these lists. | |
98 | */ | |
99 | #define SLOB_BREAK1 256 | |
100 | #define SLOB_BREAK2 1024 | |
101 | static LIST_HEAD(free_slob_small); | |
102 | static LIST_HEAD(free_slob_medium); | |
103 | static LIST_HEAD(free_slob_large); | |
104 | ||
105 | /* | |
106 | * slob_page_free: true for pages on free_slob_pages list. | |
107 | */ | |
108 | static inline int slob_page_free(struct page *sp) | |
109 | { | |
110 | return PageSlobFree(sp); | |
111 | } | |
112 | ||
113 | static void set_slob_page_free(struct page *sp, struct list_head *list) | |
114 | { | |
115 | list_add(&sp->slab_list, list); | |
116 | __SetPageSlobFree(sp); | |
117 | } | |
118 | ||
119 | static inline void clear_slob_page_free(struct page *sp) | |
120 | { | |
121 | list_del(&sp->slab_list); | |
122 | __ClearPageSlobFree(sp); | |
123 | } | |
124 | ||
125 | #define SLOB_UNIT sizeof(slob_t) | |
126 | #define SLOB_UNITS(size) DIV_ROUND_UP(size, SLOB_UNIT) | |
127 | ||
128 | /* | |
129 | * struct slob_rcu is inserted at the tail of allocated slob blocks, which | |
130 | * were created with a SLAB_TYPESAFE_BY_RCU slab. slob_rcu is used to free | |
131 | * the block using call_rcu. | |
132 | */ | |
133 | struct slob_rcu { | |
134 | struct rcu_head head; | |
135 | int size; | |
136 | }; | |
137 | ||
138 | /* | |
139 | * slob_lock protects all slob allocator structures. | |
140 | */ | |
141 | static DEFINE_SPINLOCK(slob_lock); | |
142 | ||
143 | /* | |
144 | * Encode the given size and next info into a free slob block s. | |
145 | */ | |
146 | static void set_slob(slob_t *s, slobidx_t size, slob_t *next) | |
147 | { | |
148 | slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); | |
149 | slobidx_t offset = next - base; | |
150 | ||
151 | if (size > 1) { | |
152 | s[0].units = size; | |
153 | s[1].units = offset; | |
154 | } else | |
155 | s[0].units = -offset; | |
156 | } | |
157 | ||
158 | /* | |
159 | * Return the size of a slob block. | |
160 | */ | |
161 | static slobidx_t slob_units(slob_t *s) | |
162 | { | |
163 | if (s->units > 0) | |
164 | return s->units; | |
165 | return 1; | |
166 | } | |
167 | ||
168 | /* | |
169 | * Return the next free slob block pointer after this one. | |
170 | */ | |
171 | static slob_t *slob_next(slob_t *s) | |
172 | { | |
173 | slob_t *base = (slob_t *)((unsigned long)s & PAGE_MASK); | |
174 | slobidx_t next; | |
175 | ||
176 | if (s[0].units < 0) | |
177 | next = -s[0].units; | |
178 | else | |
179 | next = s[1].units; | |
180 | return base+next; | |
181 | } | |
182 | ||
183 | /* | |
184 | * Returns true if s is the last free block in its page. | |
185 | */ | |
186 | static int slob_last(slob_t *s) | |
187 | { | |
188 | return !((unsigned long)slob_next(s) & ~PAGE_MASK); | |
189 | } | |
190 | ||
191 | static void *slob_new_pages(gfp_t gfp, int order, int node) | |
192 | { | |
193 | struct page *page; | |
194 | ||
195 | #ifdef CONFIG_NUMA | |
196 | if (node != NUMA_NO_NODE) | |
197 | page = __alloc_pages_node(node, gfp, order); | |
198 | else | |
199 | #endif | |
200 | page = alloc_pages(gfp, order); | |
201 | ||
202 | if (!page) | |
203 | return NULL; | |
204 | ||
205 | mod_node_page_state(page_pgdat(page), NR_SLAB_UNRECLAIMABLE_B, | |
206 | PAGE_SIZE << order); | |
207 | return page_address(page); | |
208 | } | |
209 | ||
210 | static void slob_free_pages(void *b, int order) | |
211 | { | |
212 | struct page *sp = virt_to_page(b); | |
213 | ||
214 | if (current->reclaim_state) | |
215 | current->reclaim_state->reclaimed_slab += 1 << order; | |
216 | ||
217 | mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, | |
218 | -(PAGE_SIZE << order)); | |
219 | __free_pages(sp, order); | |
220 | } | |
221 | ||
222 | /* | |
223 | * slob_page_alloc() - Allocate a slob block within a given slob_page sp. | |
224 | * @sp: Page to look in. | |
225 | * @size: Size of the allocation. | |
226 | * @align: Allocation alignment. | |
227 | * @align_offset: Offset in the allocated block that will be aligned. | |
228 | * @page_removed_from_list: Return parameter. | |
229 | * | |
230 | * Tries to find a chunk of memory at least @size bytes big within @page. | |
231 | * | |
232 | * Return: Pointer to memory if allocated, %NULL otherwise. If the | |
233 | * allocation fills up @page then the page is removed from the | |
234 | * freelist, in this case @page_removed_from_list will be set to | |
235 | * true (set to false otherwise). | |
236 | */ | |
237 | static void *slob_page_alloc(struct page *sp, size_t size, int align, | |
238 | int align_offset, bool *page_removed_from_list) | |
239 | { | |
240 | slob_t *prev, *cur, *aligned = NULL; | |
241 | int delta = 0, units = SLOB_UNITS(size); | |
242 | ||
243 | *page_removed_from_list = false; | |
244 | for (prev = NULL, cur = sp->freelist; ; prev = cur, cur = slob_next(cur)) { | |
245 | slobidx_t avail = slob_units(cur); | |
246 | ||
247 | /* | |
248 | * 'aligned' will hold the address of the slob block so that the | |
249 | * address 'aligned'+'align_offset' is aligned according to the | |
250 | * 'align' parameter. This is for kmalloc() which prepends the | |
251 | * allocated block with its size, so that the block itself is | |
252 | * aligned when needed. | |
253 | */ | |
254 | if (align) { | |
255 | aligned = (slob_t *) | |
256 | (ALIGN((unsigned long)cur + align_offset, align) | |
257 | - align_offset); | |
258 | delta = aligned - cur; | |
259 | } | |
260 | if (avail >= units + delta) { /* room enough? */ | |
261 | slob_t *next; | |
262 | ||
263 | if (delta) { /* need to fragment head to align? */ | |
264 | next = slob_next(cur); | |
265 | set_slob(aligned, avail - delta, next); | |
266 | set_slob(cur, delta, aligned); | |
267 | prev = cur; | |
268 | cur = aligned; | |
269 | avail = slob_units(cur); | |
270 | } | |
271 | ||
272 | next = slob_next(cur); | |
273 | if (avail == units) { /* exact fit? unlink. */ | |
274 | if (prev) | |
275 | set_slob(prev, slob_units(prev), next); | |
276 | else | |
277 | sp->freelist = next; | |
278 | } else { /* fragment */ | |
279 | if (prev) | |
280 | set_slob(prev, slob_units(prev), cur + units); | |
281 | else | |
282 | sp->freelist = cur + units; | |
283 | set_slob(cur + units, avail - units, next); | |
284 | } | |
285 | ||
286 | sp->units -= units; | |
287 | if (!sp->units) { | |
288 | clear_slob_page_free(sp); | |
289 | *page_removed_from_list = true; | |
290 | } | |
291 | return cur; | |
292 | } | |
293 | if (slob_last(cur)) | |
294 | return NULL; | |
295 | } | |
296 | } | |
297 | ||
298 | /* | |
299 | * slob_alloc: entry point into the slob allocator. | |
300 | */ | |
301 | static void *slob_alloc(size_t size, gfp_t gfp, int align, int node, | |
302 | int align_offset) | |
303 | { | |
304 | struct page *sp; | |
305 | struct list_head *slob_list; | |
306 | slob_t *b = NULL; | |
307 | unsigned long flags; | |
308 | bool _unused; | |
309 | ||
310 | if (size < SLOB_BREAK1) | |
311 | slob_list = &free_slob_small; | |
312 | else if (size < SLOB_BREAK2) | |
313 | slob_list = &free_slob_medium; | |
314 | else | |
315 | slob_list = &free_slob_large; | |
316 | ||
317 | spin_lock_irqsave(&slob_lock, flags); | |
318 | /* Iterate through each partially free page, try to find room */ | |
319 | list_for_each_entry(sp, slob_list, slab_list) { | |
320 | bool page_removed_from_list = false; | |
321 | #ifdef CONFIG_NUMA | |
322 | /* | |
323 | * If there's a node specification, search for a partial | |
324 | * page with a matching node id in the freelist. | |
325 | */ | |
326 | if (node != NUMA_NO_NODE && page_to_nid(sp) != node) | |
327 | continue; | |
328 | #endif | |
329 | /* Enough room on this page? */ | |
330 | if (sp->units < SLOB_UNITS(size)) | |
331 | continue; | |
332 | ||
333 | b = slob_page_alloc(sp, size, align, align_offset, &page_removed_from_list); | |
334 | if (!b) | |
335 | continue; | |
336 | ||
337 | /* | |
338 | * If slob_page_alloc() removed sp from the list then we | |
339 | * cannot call list functions on sp. If so allocation | |
340 | * did not fragment the page anyway so optimisation is | |
341 | * unnecessary. | |
342 | */ | |
343 | if (!page_removed_from_list) { | |
344 | /* | |
345 | * Improve fragment distribution and reduce our average | |
346 | * search time by starting our next search here. (see | |
347 | * Knuth vol 1, sec 2.5, pg 449) | |
348 | */ | |
349 | if (!list_is_first(&sp->slab_list, slob_list)) | |
350 | list_rotate_to_front(&sp->slab_list, slob_list); | |
351 | } | |
352 | break; | |
353 | } | |
354 | spin_unlock_irqrestore(&slob_lock, flags); | |
355 | ||
356 | /* Not enough space: must allocate a new page */ | |
357 | if (!b) { | |
358 | b = slob_new_pages(gfp & ~__GFP_ZERO, 0, node); | |
359 | if (!b) | |
360 | return NULL; | |
361 | sp = virt_to_page(b); | |
362 | __SetPageSlab(sp); | |
363 | ||
364 | spin_lock_irqsave(&slob_lock, flags); | |
365 | sp->units = SLOB_UNITS(PAGE_SIZE); | |
366 | sp->freelist = b; | |
367 | INIT_LIST_HEAD(&sp->slab_list); | |
368 | set_slob(b, SLOB_UNITS(PAGE_SIZE), b + SLOB_UNITS(PAGE_SIZE)); | |
369 | set_slob_page_free(sp, slob_list); | |
370 | b = slob_page_alloc(sp, size, align, align_offset, &_unused); | |
371 | BUG_ON(!b); | |
372 | spin_unlock_irqrestore(&slob_lock, flags); | |
373 | } | |
374 | if (unlikely(gfp & __GFP_ZERO)) | |
375 | memset(b, 0, size); | |
376 | return b; | |
377 | } | |
378 | ||
379 | /* | |
380 | * slob_free: entry point into the slob allocator. | |
381 | */ | |
382 | static void slob_free(void *block, int size) | |
383 | { | |
384 | struct page *sp; | |
385 | slob_t *prev, *next, *b = (slob_t *)block; | |
386 | slobidx_t units; | |
387 | unsigned long flags; | |
388 | struct list_head *slob_list; | |
389 | ||
390 | if (unlikely(ZERO_OR_NULL_PTR(block))) | |
391 | return; | |
392 | BUG_ON(!size); | |
393 | ||
394 | sp = virt_to_page(block); | |
395 | units = SLOB_UNITS(size); | |
396 | ||
397 | spin_lock_irqsave(&slob_lock, flags); | |
398 | ||
399 | if (sp->units + units == SLOB_UNITS(PAGE_SIZE)) { | |
400 | /* Go directly to page allocator. Do not pass slob allocator */ | |
401 | if (slob_page_free(sp)) | |
402 | clear_slob_page_free(sp); | |
403 | spin_unlock_irqrestore(&slob_lock, flags); | |
404 | __ClearPageSlab(sp); | |
405 | page_mapcount_reset(sp); | |
406 | slob_free_pages(b, 0); | |
407 | return; | |
408 | } | |
409 | ||
410 | if (!slob_page_free(sp)) { | |
411 | /* This slob page is about to become partially free. Easy! */ | |
412 | sp->units = units; | |
413 | sp->freelist = b; | |
414 | set_slob(b, units, | |
415 | (void *)((unsigned long)(b + | |
416 | SLOB_UNITS(PAGE_SIZE)) & PAGE_MASK)); | |
417 | if (size < SLOB_BREAK1) | |
418 | slob_list = &free_slob_small; | |
419 | else if (size < SLOB_BREAK2) | |
420 | slob_list = &free_slob_medium; | |
421 | else | |
422 | slob_list = &free_slob_large; | |
423 | set_slob_page_free(sp, slob_list); | |
424 | goto out; | |
425 | } | |
426 | ||
427 | /* | |
428 | * Otherwise the page is already partially free, so find reinsertion | |
429 | * point. | |
430 | */ | |
431 | sp->units += units; | |
432 | ||
433 | if (b < (slob_t *)sp->freelist) { | |
434 | if (b + units == sp->freelist) { | |
435 | units += slob_units(sp->freelist); | |
436 | sp->freelist = slob_next(sp->freelist); | |
437 | } | |
438 | set_slob(b, units, sp->freelist); | |
439 | sp->freelist = b; | |
440 | } else { | |
441 | prev = sp->freelist; | |
442 | next = slob_next(prev); | |
443 | while (b > next) { | |
444 | prev = next; | |
445 | next = slob_next(prev); | |
446 | } | |
447 | ||
448 | if (!slob_last(prev) && b + units == next) { | |
449 | units += slob_units(next); | |
450 | set_slob(b, units, slob_next(next)); | |
451 | } else | |
452 | set_slob(b, units, next); | |
453 | ||
454 | if (prev + slob_units(prev) == b) { | |
455 | units = slob_units(b) + slob_units(prev); | |
456 | set_slob(prev, units, slob_next(b)); | |
457 | } else | |
458 | set_slob(prev, slob_units(prev), b); | |
459 | } | |
460 | out: | |
461 | spin_unlock_irqrestore(&slob_lock, flags); | |
462 | } | |
463 | ||
464 | #ifdef CONFIG_PRINTK | |
465 | void kmem_obj_info(struct kmem_obj_info *kpp, void *object, struct page *page) | |
466 | { | |
467 | kpp->kp_ptr = object; | |
468 | kpp->kp_page = page; | |
469 | } | |
470 | #endif | |
471 | ||
472 | /* | |
473 | * End of slob allocator proper. Begin kmem_cache_alloc and kmalloc frontend. | |
474 | */ | |
475 | ||
476 | static __always_inline void * | |
477 | __do_kmalloc_node(size_t size, gfp_t gfp, int node, unsigned long caller) | |
478 | { | |
479 | unsigned int *m; | |
480 | int minalign = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN); | |
481 | void *ret; | |
482 | ||
483 | gfp &= gfp_allowed_mask; | |
484 | ||
485 | might_alloc(gfp); | |
486 | ||
487 | if (size < PAGE_SIZE - minalign) { | |
488 | int align = minalign; | |
489 | ||
490 | /* | |
491 | * For power of two sizes, guarantee natural alignment for | |
492 | * kmalloc()'d objects. | |
493 | */ | |
494 | if (is_power_of_2(size)) | |
495 | align = max(minalign, (int) size); | |
496 | ||
497 | if (!size) | |
498 | return ZERO_SIZE_PTR; | |
499 | ||
500 | m = slob_alloc(size + minalign, gfp, align, node, minalign); | |
501 | ||
502 | if (!m) | |
503 | return NULL; | |
504 | *m = size; | |
505 | ret = (void *)m + minalign; | |
506 | ||
507 | trace_kmalloc_node(caller, ret, | |
508 | size, size + minalign, gfp, node); | |
509 | } else { | |
510 | unsigned int order = get_order(size); | |
511 | ||
512 | if (likely(order)) | |
513 | gfp |= __GFP_COMP; | |
514 | ret = slob_new_pages(gfp, order, node); | |
515 | ||
516 | trace_kmalloc_node(caller, ret, | |
517 | size, PAGE_SIZE << order, gfp, node); | |
518 | } | |
519 | ||
520 | kmemleak_alloc(ret, size, 1, gfp); | |
521 | return ret; | |
522 | } | |
523 | ||
524 | void *__kmalloc(size_t size, gfp_t gfp) | |
525 | { | |
526 | return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, _RET_IP_); | |
527 | } | |
528 | EXPORT_SYMBOL(__kmalloc); | |
529 | ||
530 | void *__kmalloc_track_caller(size_t size, gfp_t gfp, unsigned long caller) | |
531 | { | |
532 | return __do_kmalloc_node(size, gfp, NUMA_NO_NODE, caller); | |
533 | } | |
534 | EXPORT_SYMBOL(__kmalloc_track_caller); | |
535 | ||
536 | #ifdef CONFIG_NUMA | |
537 | void *__kmalloc_node_track_caller(size_t size, gfp_t gfp, | |
538 | int node, unsigned long caller) | |
539 | { | |
540 | return __do_kmalloc_node(size, gfp, node, caller); | |
541 | } | |
542 | EXPORT_SYMBOL(__kmalloc_node_track_caller); | |
543 | #endif | |
544 | ||
545 | void kfree(const void *block) | |
546 | { | |
547 | struct page *sp; | |
548 | ||
549 | trace_kfree(_RET_IP_, block); | |
550 | ||
551 | if (unlikely(ZERO_OR_NULL_PTR(block))) | |
552 | return; | |
553 | kmemleak_free(block); | |
554 | ||
555 | sp = virt_to_page(block); | |
556 | if (PageSlab(sp)) { | |
557 | int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN); | |
558 | unsigned int *m = (unsigned int *)(block - align); | |
559 | slob_free(m, *m + align); | |
560 | } else { | |
561 | unsigned int order = compound_order(sp); | |
562 | mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B, | |
563 | -(PAGE_SIZE << order)); | |
564 | __free_pages(sp, order); | |
565 | ||
566 | } | |
567 | } | |
568 | EXPORT_SYMBOL(kfree); | |
569 | ||
570 | /* can't use ksize for kmem_cache_alloc memory, only kmalloc */ | |
571 | size_t __ksize(const void *block) | |
572 | { | |
573 | struct page *sp; | |
574 | int align; | |
575 | unsigned int *m; | |
576 | ||
577 | BUG_ON(!block); | |
578 | if (unlikely(block == ZERO_SIZE_PTR)) | |
579 | return 0; | |
580 | ||
581 | sp = virt_to_page(block); | |
582 | if (unlikely(!PageSlab(sp))) | |
583 | return page_size(sp); | |
584 | ||
585 | align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN); | |
586 | m = (unsigned int *)(block - align); | |
587 | return SLOB_UNITS(*m) * SLOB_UNIT; | |
588 | } | |
589 | EXPORT_SYMBOL(__ksize); | |
590 | ||
591 | int __kmem_cache_create(struct kmem_cache *c, slab_flags_t flags) | |
592 | { | |
593 | if (flags & SLAB_TYPESAFE_BY_RCU) { | |
594 | /* leave room for rcu footer at the end of object */ | |
595 | c->size += sizeof(struct slob_rcu); | |
596 | } | |
597 | c->flags = flags; | |
598 | return 0; | |
599 | } | |
600 | ||
601 | static void *slob_alloc_node(struct kmem_cache *c, gfp_t flags, int node) | |
602 | { | |
603 | void *b; | |
604 | ||
605 | flags &= gfp_allowed_mask; | |
606 | ||
607 | might_alloc(flags); | |
608 | ||
609 | if (c->size < PAGE_SIZE) { | |
610 | b = slob_alloc(c->size, flags, c->align, node, 0); | |
611 | trace_kmem_cache_alloc_node(_RET_IP_, b, c->object_size, | |
612 | SLOB_UNITS(c->size) * SLOB_UNIT, | |
613 | flags, node); | |
614 | } else { | |
615 | b = slob_new_pages(flags, get_order(c->size), node); | |
616 | trace_kmem_cache_alloc_node(_RET_IP_, b, c->object_size, | |
617 | PAGE_SIZE << get_order(c->size), | |
618 | flags, node); | |
619 | } | |
620 | ||
621 | if (b && c->ctor) { | |
622 | WARN_ON_ONCE(flags & __GFP_ZERO); | |
623 | c->ctor(b); | |
624 | } | |
625 | ||
626 | kmemleak_alloc_recursive(b, c->size, 1, c->flags, flags); | |
627 | return b; | |
628 | } | |
629 | ||
630 | void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) | |
631 | { | |
632 | return slob_alloc_node(cachep, flags, NUMA_NO_NODE); | |
633 | } | |
634 | EXPORT_SYMBOL(kmem_cache_alloc); | |
635 | ||
636 | #ifdef CONFIG_NUMA | |
637 | void *__kmalloc_node(size_t size, gfp_t gfp, int node) | |
638 | { | |
639 | return __do_kmalloc_node(size, gfp, node, _RET_IP_); | |
640 | } | |
641 | EXPORT_SYMBOL(__kmalloc_node); | |
642 | ||
643 | void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t gfp, int node) | |
644 | { | |
645 | return slob_alloc_node(cachep, gfp, node); | |
646 | } | |
647 | EXPORT_SYMBOL(kmem_cache_alloc_node); | |
648 | #endif | |
649 | ||
650 | static void __kmem_cache_free(void *b, int size) | |
651 | { | |
652 | if (size < PAGE_SIZE) | |
653 | slob_free(b, size); | |
654 | else | |
655 | slob_free_pages(b, get_order(size)); | |
656 | } | |
657 | ||
658 | static void kmem_rcu_free(struct rcu_head *head) | |
659 | { | |
660 | struct slob_rcu *slob_rcu = (struct slob_rcu *)head; | |
661 | void *b = (void *)slob_rcu - (slob_rcu->size - sizeof(struct slob_rcu)); | |
662 | ||
663 | __kmem_cache_free(b, slob_rcu->size); | |
664 | } | |
665 | ||
666 | void kmem_cache_free(struct kmem_cache *c, void *b) | |
667 | { | |
668 | kmemleak_free_recursive(b, c->flags); | |
669 | if (unlikely(c->flags & SLAB_TYPESAFE_BY_RCU)) { | |
670 | struct slob_rcu *slob_rcu; | |
671 | slob_rcu = b + (c->size - sizeof(struct slob_rcu)); | |
672 | slob_rcu->size = c->size; | |
673 | call_rcu(&slob_rcu->head, kmem_rcu_free); | |
674 | } else { | |
675 | __kmem_cache_free(b, c->size); | |
676 | } | |
677 | ||
678 | trace_kmem_cache_free(_RET_IP_, b, c->name); | |
679 | } | |
680 | EXPORT_SYMBOL(kmem_cache_free); | |
681 | ||
682 | void kmem_cache_free_bulk(struct kmem_cache *s, size_t size, void **p) | |
683 | { | |
684 | __kmem_cache_free_bulk(s, size, p); | |
685 | } | |
686 | EXPORT_SYMBOL(kmem_cache_free_bulk); | |
687 | ||
688 | int kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t size, | |
689 | void **p) | |
690 | { | |
691 | return __kmem_cache_alloc_bulk(s, flags, size, p); | |
692 | } | |
693 | EXPORT_SYMBOL(kmem_cache_alloc_bulk); | |
694 | ||
695 | int __kmem_cache_shutdown(struct kmem_cache *c) | |
696 | { | |
697 | /* No way to check for remaining objects */ | |
698 | return 0; | |
699 | } | |
700 | ||
701 | void __kmem_cache_release(struct kmem_cache *c) | |
702 | { | |
703 | } | |
704 | ||
705 | int __kmem_cache_shrink(struct kmem_cache *d) | |
706 | { | |
707 | return 0; | |
708 | } | |
709 | ||
710 | struct kmem_cache kmem_cache_boot = { | |
711 | .name = "kmem_cache", | |
712 | .size = sizeof(struct kmem_cache), | |
713 | .flags = SLAB_PANIC, | |
714 | .align = ARCH_KMALLOC_MINALIGN, | |
715 | }; | |
716 | ||
717 | void __init kmem_cache_init(void) | |
718 | { | |
719 | kmem_cache = &kmem_cache_boot; | |
720 | slab_state = UP; | |
721 | } | |
722 | ||
723 | void __init kmem_cache_init_late(void) | |
724 | { | |
725 | slab_state = FULL; | |
726 | } |