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Commit | Line | Data |
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81819f0f CL |
1 | /* |
2 | * SLUB: A slab allocator that limits cache line use instead of queuing | |
3 | * objects in per cpu and per node lists. | |
4 | * | |
5 | * The allocator synchronizes using per slab locks and only | |
6 | * uses a centralized lock to manage a pool of partial slabs. | |
7 | * | |
cde53535 | 8 | * (C) 2007 SGI, Christoph Lameter |
81819f0f CL |
9 | */ |
10 | ||
11 | #include <linux/mm.h> | |
12 | #include <linux/module.h> | |
13 | #include <linux/bit_spinlock.h> | |
14 | #include <linux/interrupt.h> | |
15 | #include <linux/bitops.h> | |
16 | #include <linux/slab.h> | |
17 | #include <linux/seq_file.h> | |
18 | #include <linux/cpu.h> | |
19 | #include <linux/cpuset.h> | |
20 | #include <linux/mempolicy.h> | |
21 | #include <linux/ctype.h> | |
3ac7fe5a | 22 | #include <linux/debugobjects.h> |
81819f0f | 23 | #include <linux/kallsyms.h> |
b9049e23 | 24 | #include <linux/memory.h> |
f8bd2258 | 25 | #include <linux/math64.h> |
81819f0f CL |
26 | |
27 | /* | |
28 | * Lock order: | |
29 | * 1. slab_lock(page) | |
30 | * 2. slab->list_lock | |
31 | * | |
32 | * The slab_lock protects operations on the object of a particular | |
33 | * slab and its metadata in the page struct. If the slab lock | |
34 | * has been taken then no allocations nor frees can be performed | |
35 | * on the objects in the slab nor can the slab be added or removed | |
36 | * from the partial or full lists since this would mean modifying | |
37 | * the page_struct of the slab. | |
38 | * | |
39 | * The list_lock protects the partial and full list on each node and | |
40 | * the partial slab counter. If taken then no new slabs may be added or | |
41 | * removed from the lists nor make the number of partial slabs be modified. | |
42 | * (Note that the total number of slabs is an atomic value that may be | |
43 | * modified without taking the list lock). | |
44 | * | |
45 | * The list_lock is a centralized lock and thus we avoid taking it as | |
46 | * much as possible. As long as SLUB does not have to handle partial | |
47 | * slabs, operations can continue without any centralized lock. F.e. | |
48 | * allocating a long series of objects that fill up slabs does not require | |
49 | * the list lock. | |
50 | * | |
51 | * The lock order is sometimes inverted when we are trying to get a slab | |
52 | * off a list. We take the list_lock and then look for a page on the list | |
53 | * to use. While we do that objects in the slabs may be freed. We can | |
54 | * only operate on the slab if we have also taken the slab_lock. So we use | |
55 | * a slab_trylock() on the slab. If trylock was successful then no frees | |
56 | * can occur anymore and we can use the slab for allocations etc. If the | |
57 | * slab_trylock() does not succeed then frees are in progress in the slab and | |
58 | * we must stay away from it for a while since we may cause a bouncing | |
59 | * cacheline if we try to acquire the lock. So go onto the next slab. | |
60 | * If all pages are busy then we may allocate a new slab instead of reusing | |
61 | * a partial slab. A new slab has noone operating on it and thus there is | |
62 | * no danger of cacheline contention. | |
63 | * | |
64 | * Interrupts are disabled during allocation and deallocation in order to | |
65 | * make the slab allocator safe to use in the context of an irq. In addition | |
66 | * interrupts are disabled to ensure that the processor does not change | |
67 | * while handling per_cpu slabs, due to kernel preemption. | |
68 | * | |
69 | * SLUB assigns one slab for allocation to each processor. | |
70 | * Allocations only occur from these slabs called cpu slabs. | |
71 | * | |
672bba3a CL |
72 | * Slabs with free elements are kept on a partial list and during regular |
73 | * operations no list for full slabs is used. If an object in a full slab is | |
81819f0f | 74 | * freed then the slab will show up again on the partial lists. |
672bba3a CL |
75 | * We track full slabs for debugging purposes though because otherwise we |
76 | * cannot scan all objects. | |
81819f0f CL |
77 | * |
78 | * Slabs are freed when they become empty. Teardown and setup is | |
79 | * minimal so we rely on the page allocators per cpu caches for | |
80 | * fast frees and allocs. | |
81 | * | |
82 | * Overloading of page flags that are otherwise used for LRU management. | |
83 | * | |
4b6f0750 CL |
84 | * PageActive The slab is frozen and exempt from list processing. |
85 | * This means that the slab is dedicated to a purpose | |
86 | * such as satisfying allocations for a specific | |
87 | * processor. Objects may be freed in the slab while | |
88 | * it is frozen but slab_free will then skip the usual | |
89 | * list operations. It is up to the processor holding | |
90 | * the slab to integrate the slab into the slab lists | |
91 | * when the slab is no longer needed. | |
92 | * | |
93 | * One use of this flag is to mark slabs that are | |
94 | * used for allocations. Then such a slab becomes a cpu | |
95 | * slab. The cpu slab may be equipped with an additional | |
dfb4f096 | 96 | * freelist that allows lockless access to |
894b8788 CL |
97 | * free objects in addition to the regular freelist |
98 | * that requires the slab lock. | |
81819f0f CL |
99 | * |
100 | * PageError Slab requires special handling due to debug | |
101 | * options set. This moves slab handling out of | |
894b8788 | 102 | * the fast path and disables lockless freelists. |
81819f0f CL |
103 | */ |
104 | ||
5577bd8a CL |
105 | #define FROZEN (1 << PG_active) |
106 | ||
107 | #ifdef CONFIG_SLUB_DEBUG | |
108 | #define SLABDEBUG (1 << PG_error) | |
109 | #else | |
110 | #define SLABDEBUG 0 | |
111 | #endif | |
112 | ||
4b6f0750 CL |
113 | static inline int SlabFrozen(struct page *page) |
114 | { | |
5577bd8a | 115 | return page->flags & FROZEN; |
4b6f0750 CL |
116 | } |
117 | ||
118 | static inline void SetSlabFrozen(struct page *page) | |
119 | { | |
5577bd8a | 120 | page->flags |= FROZEN; |
4b6f0750 CL |
121 | } |
122 | ||
123 | static inline void ClearSlabFrozen(struct page *page) | |
124 | { | |
5577bd8a | 125 | page->flags &= ~FROZEN; |
4b6f0750 CL |
126 | } |
127 | ||
35e5d7ee CL |
128 | static inline int SlabDebug(struct page *page) |
129 | { | |
5577bd8a | 130 | return page->flags & SLABDEBUG; |
35e5d7ee CL |
131 | } |
132 | ||
133 | static inline void SetSlabDebug(struct page *page) | |
134 | { | |
5577bd8a | 135 | page->flags |= SLABDEBUG; |
35e5d7ee CL |
136 | } |
137 | ||
138 | static inline void ClearSlabDebug(struct page *page) | |
139 | { | |
5577bd8a | 140 | page->flags &= ~SLABDEBUG; |
35e5d7ee CL |
141 | } |
142 | ||
81819f0f CL |
143 | /* |
144 | * Issues still to be resolved: | |
145 | * | |
81819f0f CL |
146 | * - Support PAGE_ALLOC_DEBUG. Should be easy to do. |
147 | * | |
81819f0f CL |
148 | * - Variable sizing of the per node arrays |
149 | */ | |
150 | ||
151 | /* Enable to test recovery from slab corruption on boot */ | |
152 | #undef SLUB_RESILIENCY_TEST | |
153 | ||
2086d26a CL |
154 | /* |
155 | * Mininum number of partial slabs. These will be left on the partial | |
156 | * lists even if they are empty. kmem_cache_shrink may reclaim them. | |
157 | */ | |
76be8950 | 158 | #define MIN_PARTIAL 5 |
e95eed57 | 159 | |
2086d26a CL |
160 | /* |
161 | * Maximum number of desirable partial slabs. | |
162 | * The existence of more partial slabs makes kmem_cache_shrink | |
163 | * sort the partial list by the number of objects in the. | |
164 | */ | |
165 | #define MAX_PARTIAL 10 | |
166 | ||
81819f0f CL |
167 | #define DEBUG_DEFAULT_FLAGS (SLAB_DEBUG_FREE | SLAB_RED_ZONE | \ |
168 | SLAB_POISON | SLAB_STORE_USER) | |
672bba3a | 169 | |
81819f0f CL |
170 | /* |
171 | * Set of flags that will prevent slab merging | |
172 | */ | |
173 | #define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ | |
174 | SLAB_TRACE | SLAB_DESTROY_BY_RCU) | |
175 | ||
176 | #define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \ | |
177 | SLAB_CACHE_DMA) | |
178 | ||
179 | #ifndef ARCH_KMALLOC_MINALIGN | |
47bfdc0d | 180 | #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long) |
81819f0f CL |
181 | #endif |
182 | ||
183 | #ifndef ARCH_SLAB_MINALIGN | |
47bfdc0d | 184 | #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long) |
81819f0f CL |
185 | #endif |
186 | ||
187 | /* Internal SLUB flags */ | |
1ceef402 CL |
188 | #define __OBJECT_POISON 0x80000000 /* Poison object */ |
189 | #define __SYSFS_ADD_DEFERRED 0x40000000 /* Not yet visible via sysfs */ | |
81819f0f CL |
190 | |
191 | static int kmem_size = sizeof(struct kmem_cache); | |
192 | ||
193 | #ifdef CONFIG_SMP | |
194 | static struct notifier_block slab_notifier; | |
195 | #endif | |
196 | ||
197 | static enum { | |
198 | DOWN, /* No slab functionality available */ | |
199 | PARTIAL, /* kmem_cache_open() works but kmalloc does not */ | |
672bba3a | 200 | UP, /* Everything works but does not show up in sysfs */ |
81819f0f CL |
201 | SYSFS /* Sysfs up */ |
202 | } slab_state = DOWN; | |
203 | ||
204 | /* A list of all slab caches on the system */ | |
205 | static DECLARE_RWSEM(slub_lock); | |
5af328a5 | 206 | static LIST_HEAD(slab_caches); |
81819f0f | 207 | |
02cbc874 CL |
208 | /* |
209 | * Tracking user of a slab. | |
210 | */ | |
211 | struct track { | |
212 | void *addr; /* Called from address */ | |
213 | int cpu; /* Was running on cpu */ | |
214 | int pid; /* Pid context */ | |
215 | unsigned long when; /* When did the operation occur */ | |
216 | }; | |
217 | ||
218 | enum track_item { TRACK_ALLOC, TRACK_FREE }; | |
219 | ||
f6acb635 | 220 | #ifdef CONFIG_SLUB_DEBUG |
81819f0f CL |
221 | static int sysfs_slab_add(struct kmem_cache *); |
222 | static int sysfs_slab_alias(struct kmem_cache *, const char *); | |
223 | static void sysfs_slab_remove(struct kmem_cache *); | |
8ff12cfc | 224 | |
81819f0f | 225 | #else |
0c710013 CL |
226 | static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; } |
227 | static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p) | |
228 | { return 0; } | |
151c602f CL |
229 | static inline void sysfs_slab_remove(struct kmem_cache *s) |
230 | { | |
231 | kfree(s); | |
232 | } | |
8ff12cfc | 233 | |
81819f0f CL |
234 | #endif |
235 | ||
8ff12cfc CL |
236 | static inline void stat(struct kmem_cache_cpu *c, enum stat_item si) |
237 | { | |
238 | #ifdef CONFIG_SLUB_STATS | |
239 | c->stat[si]++; | |
240 | #endif | |
241 | } | |
242 | ||
81819f0f CL |
243 | /******************************************************************** |
244 | * Core slab cache functions | |
245 | *******************************************************************/ | |
246 | ||
247 | int slab_is_available(void) | |
248 | { | |
249 | return slab_state >= UP; | |
250 | } | |
251 | ||
252 | static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) | |
253 | { | |
254 | #ifdef CONFIG_NUMA | |
255 | return s->node[node]; | |
256 | #else | |
257 | return &s->local_node; | |
258 | #endif | |
259 | } | |
260 | ||
dfb4f096 CL |
261 | static inline struct kmem_cache_cpu *get_cpu_slab(struct kmem_cache *s, int cpu) |
262 | { | |
4c93c355 CL |
263 | #ifdef CONFIG_SMP |
264 | return s->cpu_slab[cpu]; | |
265 | #else | |
266 | return &s->cpu_slab; | |
267 | #endif | |
dfb4f096 CL |
268 | } |
269 | ||
6446faa2 | 270 | /* Verify that a pointer has an address that is valid within a slab page */ |
02cbc874 CL |
271 | static inline int check_valid_pointer(struct kmem_cache *s, |
272 | struct page *page, const void *object) | |
273 | { | |
274 | void *base; | |
275 | ||
a973e9dd | 276 | if (!object) |
02cbc874 CL |
277 | return 1; |
278 | ||
a973e9dd | 279 | base = page_address(page); |
39b26464 | 280 | if (object < base || object >= base + page->objects * s->size || |
02cbc874 CL |
281 | (object - base) % s->size) { |
282 | return 0; | |
283 | } | |
284 | ||
285 | return 1; | |
286 | } | |
287 | ||
7656c72b CL |
288 | /* |
289 | * Slow version of get and set free pointer. | |
290 | * | |
291 | * This version requires touching the cache lines of kmem_cache which | |
292 | * we avoid to do in the fast alloc free paths. There we obtain the offset | |
293 | * from the page struct. | |
294 | */ | |
295 | static inline void *get_freepointer(struct kmem_cache *s, void *object) | |
296 | { | |
297 | return *(void **)(object + s->offset); | |
298 | } | |
299 | ||
300 | static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp) | |
301 | { | |
302 | *(void **)(object + s->offset) = fp; | |
303 | } | |
304 | ||
305 | /* Loop over all objects in a slab */ | |
224a88be CL |
306 | #define for_each_object(__p, __s, __addr, __objects) \ |
307 | for (__p = (__addr); __p < (__addr) + (__objects) * (__s)->size;\ | |
7656c72b CL |
308 | __p += (__s)->size) |
309 | ||
310 | /* Scan freelist */ | |
311 | #define for_each_free_object(__p, __s, __free) \ | |
a973e9dd | 312 | for (__p = (__free); __p; __p = get_freepointer((__s), __p)) |
7656c72b CL |
313 | |
314 | /* Determine object index from a given position */ | |
315 | static inline int slab_index(void *p, struct kmem_cache *s, void *addr) | |
316 | { | |
317 | return (p - addr) / s->size; | |
318 | } | |
319 | ||
834f3d11 CL |
320 | static inline struct kmem_cache_order_objects oo_make(int order, |
321 | unsigned long size) | |
322 | { | |
323 | struct kmem_cache_order_objects x = { | |
324 | (order << 16) + (PAGE_SIZE << order) / size | |
325 | }; | |
326 | ||
327 | return x; | |
328 | } | |
329 | ||
330 | static inline int oo_order(struct kmem_cache_order_objects x) | |
331 | { | |
332 | return x.x >> 16; | |
333 | } | |
334 | ||
335 | static inline int oo_objects(struct kmem_cache_order_objects x) | |
336 | { | |
337 | return x.x & ((1 << 16) - 1); | |
338 | } | |
339 | ||
41ecc55b CL |
340 | #ifdef CONFIG_SLUB_DEBUG |
341 | /* | |
342 | * Debug settings: | |
343 | */ | |
f0630fff CL |
344 | #ifdef CONFIG_SLUB_DEBUG_ON |
345 | static int slub_debug = DEBUG_DEFAULT_FLAGS; | |
346 | #else | |
41ecc55b | 347 | static int slub_debug; |
f0630fff | 348 | #endif |
41ecc55b CL |
349 | |
350 | static char *slub_debug_slabs; | |
351 | ||
81819f0f CL |
352 | /* |
353 | * Object debugging | |
354 | */ | |
355 | static void print_section(char *text, u8 *addr, unsigned int length) | |
356 | { | |
357 | int i, offset; | |
358 | int newline = 1; | |
359 | char ascii[17]; | |
360 | ||
361 | ascii[16] = 0; | |
362 | ||
363 | for (i = 0; i < length; i++) { | |
364 | if (newline) { | |
24922684 | 365 | printk(KERN_ERR "%8s 0x%p: ", text, addr + i); |
81819f0f CL |
366 | newline = 0; |
367 | } | |
06428780 | 368 | printk(KERN_CONT " %02x", addr[i]); |
81819f0f CL |
369 | offset = i % 16; |
370 | ascii[offset] = isgraph(addr[i]) ? addr[i] : '.'; | |
371 | if (offset == 15) { | |
06428780 | 372 | printk(KERN_CONT " %s\n", ascii); |
81819f0f CL |
373 | newline = 1; |
374 | } | |
375 | } | |
376 | if (!newline) { | |
377 | i %= 16; | |
378 | while (i < 16) { | |
06428780 | 379 | printk(KERN_CONT " "); |
81819f0f CL |
380 | ascii[i] = ' '; |
381 | i++; | |
382 | } | |
06428780 | 383 | printk(KERN_CONT " %s\n", ascii); |
81819f0f CL |
384 | } |
385 | } | |
386 | ||
81819f0f CL |
387 | static struct track *get_track(struct kmem_cache *s, void *object, |
388 | enum track_item alloc) | |
389 | { | |
390 | struct track *p; | |
391 | ||
392 | if (s->offset) | |
393 | p = object + s->offset + sizeof(void *); | |
394 | else | |
395 | p = object + s->inuse; | |
396 | ||
397 | return p + alloc; | |
398 | } | |
399 | ||
400 | static void set_track(struct kmem_cache *s, void *object, | |
401 | enum track_item alloc, void *addr) | |
402 | { | |
403 | struct track *p; | |
404 | ||
405 | if (s->offset) | |
406 | p = object + s->offset + sizeof(void *); | |
407 | else | |
408 | p = object + s->inuse; | |
409 | ||
410 | p += alloc; | |
411 | if (addr) { | |
412 | p->addr = addr; | |
413 | p->cpu = smp_processor_id(); | |
414 | p->pid = current ? current->pid : -1; | |
415 | p->when = jiffies; | |
416 | } else | |
417 | memset(p, 0, sizeof(struct track)); | |
418 | } | |
419 | ||
81819f0f CL |
420 | static void init_tracking(struct kmem_cache *s, void *object) |
421 | { | |
24922684 CL |
422 | if (!(s->flags & SLAB_STORE_USER)) |
423 | return; | |
424 | ||
425 | set_track(s, object, TRACK_FREE, NULL); | |
426 | set_track(s, object, TRACK_ALLOC, NULL); | |
81819f0f CL |
427 | } |
428 | ||
429 | static void print_track(const char *s, struct track *t) | |
430 | { | |
431 | if (!t->addr) | |
432 | return; | |
433 | ||
24922684 | 434 | printk(KERN_ERR "INFO: %s in ", s); |
81819f0f | 435 | __print_symbol("%s", (unsigned long)t->addr); |
24922684 CL |
436 | printk(" age=%lu cpu=%u pid=%d\n", jiffies - t->when, t->cpu, t->pid); |
437 | } | |
438 | ||
439 | static void print_tracking(struct kmem_cache *s, void *object) | |
440 | { | |
441 | if (!(s->flags & SLAB_STORE_USER)) | |
442 | return; | |
443 | ||
444 | print_track("Allocated", get_track(s, object, TRACK_ALLOC)); | |
445 | print_track("Freed", get_track(s, object, TRACK_FREE)); | |
446 | } | |
447 | ||
448 | static void print_page_info(struct page *page) | |
449 | { | |
39b26464 CL |
450 | printk(KERN_ERR "INFO: Slab 0x%p objects=%u used=%u fp=0x%p flags=0x%04lx\n", |
451 | page, page->objects, page->inuse, page->freelist, page->flags); | |
24922684 CL |
452 | |
453 | } | |
454 | ||
455 | static void slab_bug(struct kmem_cache *s, char *fmt, ...) | |
456 | { | |
457 | va_list args; | |
458 | char buf[100]; | |
459 | ||
460 | va_start(args, fmt); | |
461 | vsnprintf(buf, sizeof(buf), fmt, args); | |
462 | va_end(args); | |
463 | printk(KERN_ERR "========================================" | |
464 | "=====================================\n"); | |
465 | printk(KERN_ERR "BUG %s: %s\n", s->name, buf); | |
466 | printk(KERN_ERR "----------------------------------------" | |
467 | "-------------------------------------\n\n"); | |
81819f0f CL |
468 | } |
469 | ||
24922684 CL |
470 | static void slab_fix(struct kmem_cache *s, char *fmt, ...) |
471 | { | |
472 | va_list args; | |
473 | char buf[100]; | |
474 | ||
475 | va_start(args, fmt); | |
476 | vsnprintf(buf, sizeof(buf), fmt, args); | |
477 | va_end(args); | |
478 | printk(KERN_ERR "FIX %s: %s\n", s->name, buf); | |
479 | } | |
480 | ||
481 | static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p) | |
81819f0f CL |
482 | { |
483 | unsigned int off; /* Offset of last byte */ | |
a973e9dd | 484 | u8 *addr = page_address(page); |
24922684 CL |
485 | |
486 | print_tracking(s, p); | |
487 | ||
488 | print_page_info(page); | |
489 | ||
490 | printk(KERN_ERR "INFO: Object 0x%p @offset=%tu fp=0x%p\n\n", | |
491 | p, p - addr, get_freepointer(s, p)); | |
492 | ||
493 | if (p > addr + 16) | |
494 | print_section("Bytes b4", p - 16, 16); | |
495 | ||
496 | print_section("Object", p, min(s->objsize, 128)); | |
81819f0f CL |
497 | |
498 | if (s->flags & SLAB_RED_ZONE) | |
499 | print_section("Redzone", p + s->objsize, | |
500 | s->inuse - s->objsize); | |
501 | ||
81819f0f CL |
502 | if (s->offset) |
503 | off = s->offset + sizeof(void *); | |
504 | else | |
505 | off = s->inuse; | |
506 | ||
24922684 | 507 | if (s->flags & SLAB_STORE_USER) |
81819f0f | 508 | off += 2 * sizeof(struct track); |
81819f0f CL |
509 | |
510 | if (off != s->size) | |
511 | /* Beginning of the filler is the free pointer */ | |
24922684 CL |
512 | print_section("Padding", p + off, s->size - off); |
513 | ||
514 | dump_stack(); | |
81819f0f CL |
515 | } |
516 | ||
517 | static void object_err(struct kmem_cache *s, struct page *page, | |
518 | u8 *object, char *reason) | |
519 | { | |
3dc50637 | 520 | slab_bug(s, "%s", reason); |
24922684 | 521 | print_trailer(s, page, object); |
81819f0f CL |
522 | } |
523 | ||
24922684 | 524 | static void slab_err(struct kmem_cache *s, struct page *page, char *fmt, ...) |
81819f0f CL |
525 | { |
526 | va_list args; | |
527 | char buf[100]; | |
528 | ||
24922684 CL |
529 | va_start(args, fmt); |
530 | vsnprintf(buf, sizeof(buf), fmt, args); | |
81819f0f | 531 | va_end(args); |
3dc50637 | 532 | slab_bug(s, "%s", buf); |
24922684 | 533 | print_page_info(page); |
81819f0f CL |
534 | dump_stack(); |
535 | } | |
536 | ||
537 | static void init_object(struct kmem_cache *s, void *object, int active) | |
538 | { | |
539 | u8 *p = object; | |
540 | ||
541 | if (s->flags & __OBJECT_POISON) { | |
542 | memset(p, POISON_FREE, s->objsize - 1); | |
06428780 | 543 | p[s->objsize - 1] = POISON_END; |
81819f0f CL |
544 | } |
545 | ||
546 | if (s->flags & SLAB_RED_ZONE) | |
547 | memset(p + s->objsize, | |
548 | active ? SLUB_RED_ACTIVE : SLUB_RED_INACTIVE, | |
549 | s->inuse - s->objsize); | |
550 | } | |
551 | ||
24922684 | 552 | static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes) |
81819f0f CL |
553 | { |
554 | while (bytes) { | |
555 | if (*start != (u8)value) | |
24922684 | 556 | return start; |
81819f0f CL |
557 | start++; |
558 | bytes--; | |
559 | } | |
24922684 CL |
560 | return NULL; |
561 | } | |
562 | ||
563 | static void restore_bytes(struct kmem_cache *s, char *message, u8 data, | |
564 | void *from, void *to) | |
565 | { | |
566 | slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data); | |
567 | memset(from, data, to - from); | |
568 | } | |
569 | ||
570 | static int check_bytes_and_report(struct kmem_cache *s, struct page *page, | |
571 | u8 *object, char *what, | |
06428780 | 572 | u8 *start, unsigned int value, unsigned int bytes) |
24922684 CL |
573 | { |
574 | u8 *fault; | |
575 | u8 *end; | |
576 | ||
577 | fault = check_bytes(start, value, bytes); | |
578 | if (!fault) | |
579 | return 1; | |
580 | ||
581 | end = start + bytes; | |
582 | while (end > fault && end[-1] == value) | |
583 | end--; | |
584 | ||
585 | slab_bug(s, "%s overwritten", what); | |
586 | printk(KERN_ERR "INFO: 0x%p-0x%p. First byte 0x%x instead of 0x%x\n", | |
587 | fault, end - 1, fault[0], value); | |
588 | print_trailer(s, page, object); | |
589 | ||
590 | restore_bytes(s, what, value, fault, end); | |
591 | return 0; | |
81819f0f CL |
592 | } |
593 | ||
81819f0f CL |
594 | /* |
595 | * Object layout: | |
596 | * | |
597 | * object address | |
598 | * Bytes of the object to be managed. | |
599 | * If the freepointer may overlay the object then the free | |
600 | * pointer is the first word of the object. | |
672bba3a | 601 | * |
81819f0f CL |
602 | * Poisoning uses 0x6b (POISON_FREE) and the last byte is |
603 | * 0xa5 (POISON_END) | |
604 | * | |
605 | * object + s->objsize | |
606 | * Padding to reach word boundary. This is also used for Redzoning. | |
672bba3a CL |
607 | * Padding is extended by another word if Redzoning is enabled and |
608 | * objsize == inuse. | |
609 | * | |
81819f0f CL |
610 | * We fill with 0xbb (RED_INACTIVE) for inactive objects and with |
611 | * 0xcc (RED_ACTIVE) for objects in use. | |
612 | * | |
613 | * object + s->inuse | |
672bba3a CL |
614 | * Meta data starts here. |
615 | * | |
81819f0f CL |
616 | * A. Free pointer (if we cannot overwrite object on free) |
617 | * B. Tracking data for SLAB_STORE_USER | |
672bba3a | 618 | * C. Padding to reach required alignment boundary or at mininum |
6446faa2 | 619 | * one word if debugging is on to be able to detect writes |
672bba3a CL |
620 | * before the word boundary. |
621 | * | |
622 | * Padding is done using 0x5a (POISON_INUSE) | |
81819f0f CL |
623 | * |
624 | * object + s->size | |
672bba3a | 625 | * Nothing is used beyond s->size. |
81819f0f | 626 | * |
672bba3a CL |
627 | * If slabcaches are merged then the objsize and inuse boundaries are mostly |
628 | * ignored. And therefore no slab options that rely on these boundaries | |
81819f0f CL |
629 | * may be used with merged slabcaches. |
630 | */ | |
631 | ||
81819f0f CL |
632 | static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p) |
633 | { | |
634 | unsigned long off = s->inuse; /* The end of info */ | |
635 | ||
636 | if (s->offset) | |
637 | /* Freepointer is placed after the object. */ | |
638 | off += sizeof(void *); | |
639 | ||
640 | if (s->flags & SLAB_STORE_USER) | |
641 | /* We also have user information there */ | |
642 | off += 2 * sizeof(struct track); | |
643 | ||
644 | if (s->size == off) | |
645 | return 1; | |
646 | ||
24922684 CL |
647 | return check_bytes_and_report(s, page, p, "Object padding", |
648 | p + off, POISON_INUSE, s->size - off); | |
81819f0f CL |
649 | } |
650 | ||
39b26464 | 651 | /* Check the pad bytes at the end of a slab page */ |
81819f0f CL |
652 | static int slab_pad_check(struct kmem_cache *s, struct page *page) |
653 | { | |
24922684 CL |
654 | u8 *start; |
655 | u8 *fault; | |
656 | u8 *end; | |
657 | int length; | |
658 | int remainder; | |
81819f0f CL |
659 | |
660 | if (!(s->flags & SLAB_POISON)) | |
661 | return 1; | |
662 | ||
a973e9dd | 663 | start = page_address(page); |
834f3d11 | 664 | length = (PAGE_SIZE << compound_order(page)); |
39b26464 CL |
665 | end = start + length; |
666 | remainder = length % s->size; | |
81819f0f CL |
667 | if (!remainder) |
668 | return 1; | |
669 | ||
39b26464 | 670 | fault = check_bytes(end - remainder, POISON_INUSE, remainder); |
24922684 CL |
671 | if (!fault) |
672 | return 1; | |
673 | while (end > fault && end[-1] == POISON_INUSE) | |
674 | end--; | |
675 | ||
676 | slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1); | |
39b26464 | 677 | print_section("Padding", end - remainder, remainder); |
24922684 CL |
678 | |
679 | restore_bytes(s, "slab padding", POISON_INUSE, start, end); | |
680 | return 0; | |
81819f0f CL |
681 | } |
682 | ||
683 | static int check_object(struct kmem_cache *s, struct page *page, | |
684 | void *object, int active) | |
685 | { | |
686 | u8 *p = object; | |
687 | u8 *endobject = object + s->objsize; | |
688 | ||
689 | if (s->flags & SLAB_RED_ZONE) { | |
690 | unsigned int red = | |
691 | active ? SLUB_RED_ACTIVE : SLUB_RED_INACTIVE; | |
692 | ||
24922684 CL |
693 | if (!check_bytes_and_report(s, page, object, "Redzone", |
694 | endobject, red, s->inuse - s->objsize)) | |
81819f0f | 695 | return 0; |
81819f0f | 696 | } else { |
3adbefee IM |
697 | if ((s->flags & SLAB_POISON) && s->objsize < s->inuse) { |
698 | check_bytes_and_report(s, page, p, "Alignment padding", | |
699 | endobject, POISON_INUSE, s->inuse - s->objsize); | |
700 | } | |
81819f0f CL |
701 | } |
702 | ||
703 | if (s->flags & SLAB_POISON) { | |
704 | if (!active && (s->flags & __OBJECT_POISON) && | |
24922684 CL |
705 | (!check_bytes_and_report(s, page, p, "Poison", p, |
706 | POISON_FREE, s->objsize - 1) || | |
707 | !check_bytes_and_report(s, page, p, "Poison", | |
06428780 | 708 | p + s->objsize - 1, POISON_END, 1))) |
81819f0f | 709 | return 0; |
81819f0f CL |
710 | /* |
711 | * check_pad_bytes cleans up on its own. | |
712 | */ | |
713 | check_pad_bytes(s, page, p); | |
714 | } | |
715 | ||
716 | if (!s->offset && active) | |
717 | /* | |
718 | * Object and freepointer overlap. Cannot check | |
719 | * freepointer while object is allocated. | |
720 | */ | |
721 | return 1; | |
722 | ||
723 | /* Check free pointer validity */ | |
724 | if (!check_valid_pointer(s, page, get_freepointer(s, p))) { | |
725 | object_err(s, page, p, "Freepointer corrupt"); | |
726 | /* | |
727 | * No choice but to zap it and thus loose the remainder | |
728 | * of the free objects in this slab. May cause | |
672bba3a | 729 | * another error because the object count is now wrong. |
81819f0f | 730 | */ |
a973e9dd | 731 | set_freepointer(s, p, NULL); |
81819f0f CL |
732 | return 0; |
733 | } | |
734 | return 1; | |
735 | } | |
736 | ||
737 | static int check_slab(struct kmem_cache *s, struct page *page) | |
738 | { | |
39b26464 CL |
739 | int maxobj; |
740 | ||
81819f0f CL |
741 | VM_BUG_ON(!irqs_disabled()); |
742 | ||
743 | if (!PageSlab(page)) { | |
24922684 | 744 | slab_err(s, page, "Not a valid slab page"); |
81819f0f CL |
745 | return 0; |
746 | } | |
39b26464 CL |
747 | |
748 | maxobj = (PAGE_SIZE << compound_order(page)) / s->size; | |
749 | if (page->objects > maxobj) { | |
750 | slab_err(s, page, "objects %u > max %u", | |
751 | s->name, page->objects, maxobj); | |
752 | return 0; | |
753 | } | |
754 | if (page->inuse > page->objects) { | |
24922684 | 755 | slab_err(s, page, "inuse %u > max %u", |
39b26464 | 756 | s->name, page->inuse, page->objects); |
81819f0f CL |
757 | return 0; |
758 | } | |
759 | /* Slab_pad_check fixes things up after itself */ | |
760 | slab_pad_check(s, page); | |
761 | return 1; | |
762 | } | |
763 | ||
764 | /* | |
672bba3a CL |
765 | * Determine if a certain object on a page is on the freelist. Must hold the |
766 | * slab lock to guarantee that the chains are in a consistent state. | |
81819f0f CL |
767 | */ |
768 | static int on_freelist(struct kmem_cache *s, struct page *page, void *search) | |
769 | { | |
770 | int nr = 0; | |
771 | void *fp = page->freelist; | |
772 | void *object = NULL; | |
224a88be | 773 | unsigned long max_objects; |
81819f0f | 774 | |
39b26464 | 775 | while (fp && nr <= page->objects) { |
81819f0f CL |
776 | if (fp == search) |
777 | return 1; | |
778 | if (!check_valid_pointer(s, page, fp)) { | |
779 | if (object) { | |
780 | object_err(s, page, object, | |
781 | "Freechain corrupt"); | |
a973e9dd | 782 | set_freepointer(s, object, NULL); |
81819f0f CL |
783 | break; |
784 | } else { | |
24922684 | 785 | slab_err(s, page, "Freepointer corrupt"); |
a973e9dd | 786 | page->freelist = NULL; |
39b26464 | 787 | page->inuse = page->objects; |
24922684 | 788 | slab_fix(s, "Freelist cleared"); |
81819f0f CL |
789 | return 0; |
790 | } | |
791 | break; | |
792 | } | |
793 | object = fp; | |
794 | fp = get_freepointer(s, object); | |
795 | nr++; | |
796 | } | |
797 | ||
224a88be CL |
798 | max_objects = (PAGE_SIZE << compound_order(page)) / s->size; |
799 | if (max_objects > 65535) | |
800 | max_objects = 65535; | |
801 | ||
802 | if (page->objects != max_objects) { | |
803 | slab_err(s, page, "Wrong number of objects. Found %d but " | |
804 | "should be %d", page->objects, max_objects); | |
805 | page->objects = max_objects; | |
806 | slab_fix(s, "Number of objects adjusted."); | |
807 | } | |
39b26464 | 808 | if (page->inuse != page->objects - nr) { |
70d71228 | 809 | slab_err(s, page, "Wrong object count. Counter is %d but " |
39b26464 CL |
810 | "counted were %d", page->inuse, page->objects - nr); |
811 | page->inuse = page->objects - nr; | |
24922684 | 812 | slab_fix(s, "Object count adjusted."); |
81819f0f CL |
813 | } |
814 | return search == NULL; | |
815 | } | |
816 | ||
0121c619 CL |
817 | static void trace(struct kmem_cache *s, struct page *page, void *object, |
818 | int alloc) | |
3ec09742 CL |
819 | { |
820 | if (s->flags & SLAB_TRACE) { | |
821 | printk(KERN_INFO "TRACE %s %s 0x%p inuse=%d fp=0x%p\n", | |
822 | s->name, | |
823 | alloc ? "alloc" : "free", | |
824 | object, page->inuse, | |
825 | page->freelist); | |
826 | ||
827 | if (!alloc) | |
828 | print_section("Object", (void *)object, s->objsize); | |
829 | ||
830 | dump_stack(); | |
831 | } | |
832 | } | |
833 | ||
643b1138 | 834 | /* |
672bba3a | 835 | * Tracking of fully allocated slabs for debugging purposes. |
643b1138 | 836 | */ |
e95eed57 | 837 | static void add_full(struct kmem_cache_node *n, struct page *page) |
643b1138 | 838 | { |
643b1138 CL |
839 | spin_lock(&n->list_lock); |
840 | list_add(&page->lru, &n->full); | |
841 | spin_unlock(&n->list_lock); | |
842 | } | |
843 | ||
844 | static void remove_full(struct kmem_cache *s, struct page *page) | |
845 | { | |
846 | struct kmem_cache_node *n; | |
847 | ||
848 | if (!(s->flags & SLAB_STORE_USER)) | |
849 | return; | |
850 | ||
851 | n = get_node(s, page_to_nid(page)); | |
852 | ||
853 | spin_lock(&n->list_lock); | |
854 | list_del(&page->lru); | |
855 | spin_unlock(&n->list_lock); | |
856 | } | |
857 | ||
0f389ec6 CL |
858 | /* Tracking of the number of slabs for debugging purposes */ |
859 | static inline unsigned long slabs_node(struct kmem_cache *s, int node) | |
860 | { | |
861 | struct kmem_cache_node *n = get_node(s, node); | |
862 | ||
863 | return atomic_long_read(&n->nr_slabs); | |
864 | } | |
865 | ||
205ab99d | 866 | static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects) |
0f389ec6 CL |
867 | { |
868 | struct kmem_cache_node *n = get_node(s, node); | |
869 | ||
870 | /* | |
871 | * May be called early in order to allocate a slab for the | |
872 | * kmem_cache_node structure. Solve the chicken-egg | |
873 | * dilemma by deferring the increment of the count during | |
874 | * bootstrap (see early_kmem_cache_node_alloc). | |
875 | */ | |
205ab99d | 876 | if (!NUMA_BUILD || n) { |
0f389ec6 | 877 | atomic_long_inc(&n->nr_slabs); |
205ab99d CL |
878 | atomic_long_add(objects, &n->total_objects); |
879 | } | |
0f389ec6 | 880 | } |
205ab99d | 881 | static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects) |
0f389ec6 CL |
882 | { |
883 | struct kmem_cache_node *n = get_node(s, node); | |
884 | ||
885 | atomic_long_dec(&n->nr_slabs); | |
205ab99d | 886 | atomic_long_sub(objects, &n->total_objects); |
0f389ec6 CL |
887 | } |
888 | ||
889 | /* Object debug checks for alloc/free paths */ | |
3ec09742 CL |
890 | static void setup_object_debug(struct kmem_cache *s, struct page *page, |
891 | void *object) | |
892 | { | |
893 | if (!(s->flags & (SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON))) | |
894 | return; | |
895 | ||
896 | init_object(s, object, 0); | |
897 | init_tracking(s, object); | |
898 | } | |
899 | ||
900 | static int alloc_debug_processing(struct kmem_cache *s, struct page *page, | |
901 | void *object, void *addr) | |
81819f0f CL |
902 | { |
903 | if (!check_slab(s, page)) | |
904 | goto bad; | |
905 | ||
d692ef6d | 906 | if (!on_freelist(s, page, object)) { |
24922684 | 907 | object_err(s, page, object, "Object already allocated"); |
70d71228 | 908 | goto bad; |
81819f0f CL |
909 | } |
910 | ||
911 | if (!check_valid_pointer(s, page, object)) { | |
912 | object_err(s, page, object, "Freelist Pointer check fails"); | |
70d71228 | 913 | goto bad; |
81819f0f CL |
914 | } |
915 | ||
d692ef6d | 916 | if (!check_object(s, page, object, 0)) |
81819f0f | 917 | goto bad; |
81819f0f | 918 | |
3ec09742 CL |
919 | /* Success perform special debug activities for allocs */ |
920 | if (s->flags & SLAB_STORE_USER) | |
921 | set_track(s, object, TRACK_ALLOC, addr); | |
922 | trace(s, page, object, 1); | |
923 | init_object(s, object, 1); | |
81819f0f | 924 | return 1; |
3ec09742 | 925 | |
81819f0f CL |
926 | bad: |
927 | if (PageSlab(page)) { | |
928 | /* | |
929 | * If this is a slab page then lets do the best we can | |
930 | * to avoid issues in the future. Marking all objects | |
672bba3a | 931 | * as used avoids touching the remaining objects. |
81819f0f | 932 | */ |
24922684 | 933 | slab_fix(s, "Marking all objects used"); |
39b26464 | 934 | page->inuse = page->objects; |
a973e9dd | 935 | page->freelist = NULL; |
81819f0f CL |
936 | } |
937 | return 0; | |
938 | } | |
939 | ||
3ec09742 CL |
940 | static int free_debug_processing(struct kmem_cache *s, struct page *page, |
941 | void *object, void *addr) | |
81819f0f CL |
942 | { |
943 | if (!check_slab(s, page)) | |
944 | goto fail; | |
945 | ||
946 | if (!check_valid_pointer(s, page, object)) { | |
70d71228 | 947 | slab_err(s, page, "Invalid object pointer 0x%p", object); |
81819f0f CL |
948 | goto fail; |
949 | } | |
950 | ||
951 | if (on_freelist(s, page, object)) { | |
24922684 | 952 | object_err(s, page, object, "Object already free"); |
81819f0f CL |
953 | goto fail; |
954 | } | |
955 | ||
956 | if (!check_object(s, page, object, 1)) | |
957 | return 0; | |
958 | ||
959 | if (unlikely(s != page->slab)) { | |
3adbefee | 960 | if (!PageSlab(page)) { |
70d71228 CL |
961 | slab_err(s, page, "Attempt to free object(0x%p) " |
962 | "outside of slab", object); | |
3adbefee | 963 | } else if (!page->slab) { |
81819f0f | 964 | printk(KERN_ERR |
70d71228 | 965 | "SLUB <none>: no slab for object 0x%p.\n", |
81819f0f | 966 | object); |
70d71228 | 967 | dump_stack(); |
06428780 | 968 | } else |
24922684 CL |
969 | object_err(s, page, object, |
970 | "page slab pointer corrupt."); | |
81819f0f CL |
971 | goto fail; |
972 | } | |
3ec09742 CL |
973 | |
974 | /* Special debug activities for freeing objects */ | |
a973e9dd | 975 | if (!SlabFrozen(page) && !page->freelist) |
3ec09742 CL |
976 | remove_full(s, page); |
977 | if (s->flags & SLAB_STORE_USER) | |
978 | set_track(s, object, TRACK_FREE, addr); | |
979 | trace(s, page, object, 0); | |
980 | init_object(s, object, 0); | |
81819f0f | 981 | return 1; |
3ec09742 | 982 | |
81819f0f | 983 | fail: |
24922684 | 984 | slab_fix(s, "Object at 0x%p not freed", object); |
81819f0f CL |
985 | return 0; |
986 | } | |
987 | ||
41ecc55b CL |
988 | static int __init setup_slub_debug(char *str) |
989 | { | |
f0630fff CL |
990 | slub_debug = DEBUG_DEFAULT_FLAGS; |
991 | if (*str++ != '=' || !*str) | |
992 | /* | |
993 | * No options specified. Switch on full debugging. | |
994 | */ | |
995 | goto out; | |
996 | ||
997 | if (*str == ',') | |
998 | /* | |
999 | * No options but restriction on slabs. This means full | |
1000 | * debugging for slabs matching a pattern. | |
1001 | */ | |
1002 | goto check_slabs; | |
1003 | ||
1004 | slub_debug = 0; | |
1005 | if (*str == '-') | |
1006 | /* | |
1007 | * Switch off all debugging measures. | |
1008 | */ | |
1009 | goto out; | |
1010 | ||
1011 | /* | |
1012 | * Determine which debug features should be switched on | |
1013 | */ | |
06428780 | 1014 | for (; *str && *str != ','; str++) { |
f0630fff CL |
1015 | switch (tolower(*str)) { |
1016 | case 'f': | |
1017 | slub_debug |= SLAB_DEBUG_FREE; | |
1018 | break; | |
1019 | case 'z': | |
1020 | slub_debug |= SLAB_RED_ZONE; | |
1021 | break; | |
1022 | case 'p': | |
1023 | slub_debug |= SLAB_POISON; | |
1024 | break; | |
1025 | case 'u': | |
1026 | slub_debug |= SLAB_STORE_USER; | |
1027 | break; | |
1028 | case 't': | |
1029 | slub_debug |= SLAB_TRACE; | |
1030 | break; | |
1031 | default: | |
1032 | printk(KERN_ERR "slub_debug option '%c' " | |
06428780 | 1033 | "unknown. skipped\n", *str); |
f0630fff | 1034 | } |
41ecc55b CL |
1035 | } |
1036 | ||
f0630fff | 1037 | check_slabs: |
41ecc55b CL |
1038 | if (*str == ',') |
1039 | slub_debug_slabs = str + 1; | |
f0630fff | 1040 | out: |
41ecc55b CL |
1041 | return 1; |
1042 | } | |
1043 | ||
1044 | __setup("slub_debug", setup_slub_debug); | |
1045 | ||
ba0268a8 CL |
1046 | static unsigned long kmem_cache_flags(unsigned long objsize, |
1047 | unsigned long flags, const char *name, | |
4ba9b9d0 | 1048 | void (*ctor)(struct kmem_cache *, void *)) |
41ecc55b CL |
1049 | { |
1050 | /* | |
e153362a | 1051 | * Enable debugging if selected on the kernel commandline. |
41ecc55b | 1052 | */ |
e153362a CL |
1053 | if (slub_debug && (!slub_debug_slabs || |
1054 | strncmp(slub_debug_slabs, name, strlen(slub_debug_slabs)) == 0)) | |
1055 | flags |= slub_debug; | |
ba0268a8 CL |
1056 | |
1057 | return flags; | |
41ecc55b CL |
1058 | } |
1059 | #else | |
3ec09742 CL |
1060 | static inline void setup_object_debug(struct kmem_cache *s, |
1061 | struct page *page, void *object) {} | |
41ecc55b | 1062 | |
3ec09742 CL |
1063 | static inline int alloc_debug_processing(struct kmem_cache *s, |
1064 | struct page *page, void *object, void *addr) { return 0; } | |
41ecc55b | 1065 | |
3ec09742 CL |
1066 | static inline int free_debug_processing(struct kmem_cache *s, |
1067 | struct page *page, void *object, void *addr) { return 0; } | |
41ecc55b | 1068 | |
41ecc55b CL |
1069 | static inline int slab_pad_check(struct kmem_cache *s, struct page *page) |
1070 | { return 1; } | |
1071 | static inline int check_object(struct kmem_cache *s, struct page *page, | |
1072 | void *object, int active) { return 1; } | |
3ec09742 | 1073 | static inline void add_full(struct kmem_cache_node *n, struct page *page) {} |
ba0268a8 CL |
1074 | static inline unsigned long kmem_cache_flags(unsigned long objsize, |
1075 | unsigned long flags, const char *name, | |
4ba9b9d0 | 1076 | void (*ctor)(struct kmem_cache *, void *)) |
ba0268a8 CL |
1077 | { |
1078 | return flags; | |
1079 | } | |
41ecc55b | 1080 | #define slub_debug 0 |
0f389ec6 CL |
1081 | |
1082 | static inline unsigned long slabs_node(struct kmem_cache *s, int node) | |
1083 | { return 0; } | |
205ab99d CL |
1084 | static inline void inc_slabs_node(struct kmem_cache *s, int node, |
1085 | int objects) {} | |
1086 | static inline void dec_slabs_node(struct kmem_cache *s, int node, | |
1087 | int objects) {} | |
41ecc55b | 1088 | #endif |
205ab99d | 1089 | |
81819f0f CL |
1090 | /* |
1091 | * Slab allocation and freeing | |
1092 | */ | |
65c3376a CL |
1093 | static inline struct page *alloc_slab_page(gfp_t flags, int node, |
1094 | struct kmem_cache_order_objects oo) | |
1095 | { | |
1096 | int order = oo_order(oo); | |
1097 | ||
1098 | if (node == -1) | |
1099 | return alloc_pages(flags, order); | |
1100 | else | |
1101 | return alloc_pages_node(node, flags, order); | |
1102 | } | |
1103 | ||
81819f0f CL |
1104 | static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) |
1105 | { | |
06428780 | 1106 | struct page *page; |
834f3d11 | 1107 | struct kmem_cache_order_objects oo = s->oo; |
81819f0f | 1108 | |
b7a49f0d | 1109 | flags |= s->allocflags; |
e12ba74d | 1110 | |
65c3376a CL |
1111 | page = alloc_slab_page(flags | __GFP_NOWARN | __GFP_NORETRY, node, |
1112 | oo); | |
1113 | if (unlikely(!page)) { | |
1114 | oo = s->min; | |
1115 | /* | |
1116 | * Allocation may have failed due to fragmentation. | |
1117 | * Try a lower order alloc if possible | |
1118 | */ | |
1119 | page = alloc_slab_page(flags, node, oo); | |
1120 | if (!page) | |
1121 | return NULL; | |
81819f0f | 1122 | |
65c3376a CL |
1123 | stat(get_cpu_slab(s, raw_smp_processor_id()), ORDER_FALLBACK); |
1124 | } | |
834f3d11 | 1125 | page->objects = oo_objects(oo); |
81819f0f CL |
1126 | mod_zone_page_state(page_zone(page), |
1127 | (s->flags & SLAB_RECLAIM_ACCOUNT) ? | |
1128 | NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, | |
65c3376a | 1129 | 1 << oo_order(oo)); |
81819f0f CL |
1130 | |
1131 | return page; | |
1132 | } | |
1133 | ||
1134 | static void setup_object(struct kmem_cache *s, struct page *page, | |
1135 | void *object) | |
1136 | { | |
3ec09742 | 1137 | setup_object_debug(s, page, object); |
4f104934 | 1138 | if (unlikely(s->ctor)) |
4ba9b9d0 | 1139 | s->ctor(s, object); |
81819f0f CL |
1140 | } |
1141 | ||
1142 | static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) | |
1143 | { | |
1144 | struct page *page; | |
81819f0f | 1145 | void *start; |
81819f0f CL |
1146 | void *last; |
1147 | void *p; | |
1148 | ||
6cb06229 | 1149 | BUG_ON(flags & GFP_SLAB_BUG_MASK); |
81819f0f | 1150 | |
6cb06229 CL |
1151 | page = allocate_slab(s, |
1152 | flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node); | |
81819f0f CL |
1153 | if (!page) |
1154 | goto out; | |
1155 | ||
205ab99d | 1156 | inc_slabs_node(s, page_to_nid(page), page->objects); |
81819f0f CL |
1157 | page->slab = s; |
1158 | page->flags |= 1 << PG_slab; | |
1159 | if (s->flags & (SLAB_DEBUG_FREE | SLAB_RED_ZONE | SLAB_POISON | | |
1160 | SLAB_STORE_USER | SLAB_TRACE)) | |
35e5d7ee | 1161 | SetSlabDebug(page); |
81819f0f CL |
1162 | |
1163 | start = page_address(page); | |
81819f0f CL |
1164 | |
1165 | if (unlikely(s->flags & SLAB_POISON)) | |
834f3d11 | 1166 | memset(start, POISON_INUSE, PAGE_SIZE << compound_order(page)); |
81819f0f CL |
1167 | |
1168 | last = start; | |
224a88be | 1169 | for_each_object(p, s, start, page->objects) { |
81819f0f CL |
1170 | setup_object(s, page, last); |
1171 | set_freepointer(s, last, p); | |
1172 | last = p; | |
1173 | } | |
1174 | setup_object(s, page, last); | |
a973e9dd | 1175 | set_freepointer(s, last, NULL); |
81819f0f CL |
1176 | |
1177 | page->freelist = start; | |
1178 | page->inuse = 0; | |
1179 | out: | |
81819f0f CL |
1180 | return page; |
1181 | } | |
1182 | ||
1183 | static void __free_slab(struct kmem_cache *s, struct page *page) | |
1184 | { | |
834f3d11 CL |
1185 | int order = compound_order(page); |
1186 | int pages = 1 << order; | |
81819f0f | 1187 | |
c59def9f | 1188 | if (unlikely(SlabDebug(page))) { |
81819f0f CL |
1189 | void *p; |
1190 | ||
1191 | slab_pad_check(s, page); | |
224a88be CL |
1192 | for_each_object(p, s, page_address(page), |
1193 | page->objects) | |
81819f0f | 1194 | check_object(s, page, p, 0); |
2208b764 | 1195 | ClearSlabDebug(page); |
81819f0f CL |
1196 | } |
1197 | ||
1198 | mod_zone_page_state(page_zone(page), | |
1199 | (s->flags & SLAB_RECLAIM_ACCOUNT) ? | |
1200 | NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE, | |
06428780 | 1201 | -pages); |
81819f0f | 1202 | |
49bd5221 CL |
1203 | __ClearPageSlab(page); |
1204 | reset_page_mapcount(page); | |
834f3d11 | 1205 | __free_pages(page, order); |
81819f0f CL |
1206 | } |
1207 | ||
1208 | static void rcu_free_slab(struct rcu_head *h) | |
1209 | { | |
1210 | struct page *page; | |
1211 | ||
1212 | page = container_of((struct list_head *)h, struct page, lru); | |
1213 | __free_slab(page->slab, page); | |
1214 | } | |
1215 | ||
1216 | static void free_slab(struct kmem_cache *s, struct page *page) | |
1217 | { | |
1218 | if (unlikely(s->flags & SLAB_DESTROY_BY_RCU)) { | |
1219 | /* | |
1220 | * RCU free overloads the RCU head over the LRU | |
1221 | */ | |
1222 | struct rcu_head *head = (void *)&page->lru; | |
1223 | ||
1224 | call_rcu(head, rcu_free_slab); | |
1225 | } else | |
1226 | __free_slab(s, page); | |
1227 | } | |
1228 | ||
1229 | static void discard_slab(struct kmem_cache *s, struct page *page) | |
1230 | { | |
205ab99d | 1231 | dec_slabs_node(s, page_to_nid(page), page->objects); |
81819f0f CL |
1232 | free_slab(s, page); |
1233 | } | |
1234 | ||
1235 | /* | |
1236 | * Per slab locking using the pagelock | |
1237 | */ | |
1238 | static __always_inline void slab_lock(struct page *page) | |
1239 | { | |
1240 | bit_spin_lock(PG_locked, &page->flags); | |
1241 | } | |
1242 | ||
1243 | static __always_inline void slab_unlock(struct page *page) | |
1244 | { | |
a76d3546 | 1245 | __bit_spin_unlock(PG_locked, &page->flags); |
81819f0f CL |
1246 | } |
1247 | ||
1248 | static __always_inline int slab_trylock(struct page *page) | |
1249 | { | |
1250 | int rc = 1; | |
1251 | ||
1252 | rc = bit_spin_trylock(PG_locked, &page->flags); | |
1253 | return rc; | |
1254 | } | |
1255 | ||
1256 | /* | |
1257 | * Management of partially allocated slabs | |
1258 | */ | |
7c2e132c CL |
1259 | static void add_partial(struct kmem_cache_node *n, |
1260 | struct page *page, int tail) | |
81819f0f | 1261 | { |
e95eed57 CL |
1262 | spin_lock(&n->list_lock); |
1263 | n->nr_partial++; | |
7c2e132c CL |
1264 | if (tail) |
1265 | list_add_tail(&page->lru, &n->partial); | |
1266 | else | |
1267 | list_add(&page->lru, &n->partial); | |
81819f0f CL |
1268 | spin_unlock(&n->list_lock); |
1269 | } | |
1270 | ||
0121c619 | 1271 | static void remove_partial(struct kmem_cache *s, struct page *page) |
81819f0f CL |
1272 | { |
1273 | struct kmem_cache_node *n = get_node(s, page_to_nid(page)); | |
1274 | ||
1275 | spin_lock(&n->list_lock); | |
1276 | list_del(&page->lru); | |
1277 | n->nr_partial--; | |
1278 | spin_unlock(&n->list_lock); | |
1279 | } | |
1280 | ||
1281 | /* | |
672bba3a | 1282 | * Lock slab and remove from the partial list. |
81819f0f | 1283 | * |
672bba3a | 1284 | * Must hold list_lock. |
81819f0f | 1285 | */ |
0121c619 CL |
1286 | static inline int lock_and_freeze_slab(struct kmem_cache_node *n, |
1287 | struct page *page) | |
81819f0f CL |
1288 | { |
1289 | if (slab_trylock(page)) { | |
1290 | list_del(&page->lru); | |
1291 | n->nr_partial--; | |
4b6f0750 | 1292 | SetSlabFrozen(page); |
81819f0f CL |
1293 | return 1; |
1294 | } | |
1295 | return 0; | |
1296 | } | |
1297 | ||
1298 | /* | |
672bba3a | 1299 | * Try to allocate a partial slab from a specific node. |
81819f0f CL |
1300 | */ |
1301 | static struct page *get_partial_node(struct kmem_cache_node *n) | |
1302 | { | |
1303 | struct page *page; | |
1304 | ||
1305 | /* | |
1306 | * Racy check. If we mistakenly see no partial slabs then we | |
1307 | * just allocate an empty slab. If we mistakenly try to get a | |
672bba3a CL |
1308 | * partial slab and there is none available then get_partials() |
1309 | * will return NULL. | |
81819f0f CL |
1310 | */ |
1311 | if (!n || !n->nr_partial) | |
1312 | return NULL; | |
1313 | ||
1314 | spin_lock(&n->list_lock); | |
1315 | list_for_each_entry(page, &n->partial, lru) | |
4b6f0750 | 1316 | if (lock_and_freeze_slab(n, page)) |
81819f0f CL |
1317 | goto out; |
1318 | page = NULL; | |
1319 | out: | |
1320 | spin_unlock(&n->list_lock); | |
1321 | return page; | |
1322 | } | |
1323 | ||
1324 | /* | |
672bba3a | 1325 | * Get a page from somewhere. Search in increasing NUMA distances. |
81819f0f CL |
1326 | */ |
1327 | static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags) | |
1328 | { | |
1329 | #ifdef CONFIG_NUMA | |
1330 | struct zonelist *zonelist; | |
dd1a239f | 1331 | struct zoneref *z; |
54a6eb5c MG |
1332 | struct zone *zone; |
1333 | enum zone_type high_zoneidx = gfp_zone(flags); | |
81819f0f CL |
1334 | struct page *page; |
1335 | ||
1336 | /* | |
672bba3a CL |
1337 | * The defrag ratio allows a configuration of the tradeoffs between |
1338 | * inter node defragmentation and node local allocations. A lower | |
1339 | * defrag_ratio increases the tendency to do local allocations | |
1340 | * instead of attempting to obtain partial slabs from other nodes. | |
81819f0f | 1341 | * |
672bba3a CL |
1342 | * If the defrag_ratio is set to 0 then kmalloc() always |
1343 | * returns node local objects. If the ratio is higher then kmalloc() | |
1344 | * may return off node objects because partial slabs are obtained | |
1345 | * from other nodes and filled up. | |
81819f0f | 1346 | * |
6446faa2 | 1347 | * If /sys/kernel/slab/xx/defrag_ratio is set to 100 (which makes |
672bba3a CL |
1348 | * defrag_ratio = 1000) then every (well almost) allocation will |
1349 | * first attempt to defrag slab caches on other nodes. This means | |
1350 | * scanning over all nodes to look for partial slabs which may be | |
1351 | * expensive if we do it every time we are trying to find a slab | |
1352 | * with available objects. | |
81819f0f | 1353 | */ |
9824601e CL |
1354 | if (!s->remote_node_defrag_ratio || |
1355 | get_cycles() % 1024 > s->remote_node_defrag_ratio) | |
81819f0f CL |
1356 | return NULL; |
1357 | ||
0e88460d | 1358 | zonelist = node_zonelist(slab_node(current->mempolicy), flags); |
54a6eb5c | 1359 | for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) { |
81819f0f CL |
1360 | struct kmem_cache_node *n; |
1361 | ||
54a6eb5c | 1362 | n = get_node(s, zone_to_nid(zone)); |
81819f0f | 1363 | |
54a6eb5c | 1364 | if (n && cpuset_zone_allowed_hardwall(zone, flags) && |
e95eed57 | 1365 | n->nr_partial > MIN_PARTIAL) { |
81819f0f CL |
1366 | page = get_partial_node(n); |
1367 | if (page) | |
1368 | return page; | |
1369 | } | |
1370 | } | |
1371 | #endif | |
1372 | return NULL; | |
1373 | } | |
1374 | ||
1375 | /* | |
1376 | * Get a partial page, lock it and return it. | |
1377 | */ | |
1378 | static struct page *get_partial(struct kmem_cache *s, gfp_t flags, int node) | |
1379 | { | |
1380 | struct page *page; | |
1381 | int searchnode = (node == -1) ? numa_node_id() : node; | |
1382 | ||
1383 | page = get_partial_node(get_node(s, searchnode)); | |
1384 | if (page || (flags & __GFP_THISNODE)) | |
1385 | return page; | |
1386 | ||
1387 | return get_any_partial(s, flags); | |
1388 | } | |
1389 | ||
1390 | /* | |
1391 | * Move a page back to the lists. | |
1392 | * | |
1393 | * Must be called with the slab lock held. | |
1394 | * | |
1395 | * On exit the slab lock will have been dropped. | |
1396 | */ | |
7c2e132c | 1397 | static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail) |
81819f0f | 1398 | { |
e95eed57 | 1399 | struct kmem_cache_node *n = get_node(s, page_to_nid(page)); |
8ff12cfc | 1400 | struct kmem_cache_cpu *c = get_cpu_slab(s, smp_processor_id()); |
e95eed57 | 1401 | |
4b6f0750 | 1402 | ClearSlabFrozen(page); |
81819f0f | 1403 | if (page->inuse) { |
e95eed57 | 1404 | |
a973e9dd | 1405 | if (page->freelist) { |
7c2e132c | 1406 | add_partial(n, page, tail); |
8ff12cfc CL |
1407 | stat(c, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD); |
1408 | } else { | |
1409 | stat(c, DEACTIVATE_FULL); | |
1410 | if (SlabDebug(page) && (s->flags & SLAB_STORE_USER)) | |
1411 | add_full(n, page); | |
1412 | } | |
81819f0f CL |
1413 | slab_unlock(page); |
1414 | } else { | |
8ff12cfc | 1415 | stat(c, DEACTIVATE_EMPTY); |
e95eed57 CL |
1416 | if (n->nr_partial < MIN_PARTIAL) { |
1417 | /* | |
672bba3a CL |
1418 | * Adding an empty slab to the partial slabs in order |
1419 | * to avoid page allocator overhead. This slab needs | |
1420 | * to come after the other slabs with objects in | |
6446faa2 CL |
1421 | * so that the others get filled first. That way the |
1422 | * size of the partial list stays small. | |
1423 | * | |
0121c619 CL |
1424 | * kmem_cache_shrink can reclaim any empty slabs from |
1425 | * the partial list. | |
e95eed57 | 1426 | */ |
7c2e132c | 1427 | add_partial(n, page, 1); |
e95eed57 CL |
1428 | slab_unlock(page); |
1429 | } else { | |
1430 | slab_unlock(page); | |
8ff12cfc | 1431 | stat(get_cpu_slab(s, raw_smp_processor_id()), FREE_SLAB); |
e95eed57 CL |
1432 | discard_slab(s, page); |
1433 | } | |
81819f0f CL |
1434 | } |
1435 | } | |
1436 | ||
1437 | /* | |
1438 | * Remove the cpu slab | |
1439 | */ | |
dfb4f096 | 1440 | static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) |
81819f0f | 1441 | { |
dfb4f096 | 1442 | struct page *page = c->page; |
7c2e132c | 1443 | int tail = 1; |
8ff12cfc | 1444 | |
b773ad73 | 1445 | if (page->freelist) |
8ff12cfc | 1446 | stat(c, DEACTIVATE_REMOTE_FREES); |
894b8788 | 1447 | /* |
6446faa2 | 1448 | * Merge cpu freelist into slab freelist. Typically we get here |
894b8788 CL |
1449 | * because both freelists are empty. So this is unlikely |
1450 | * to occur. | |
1451 | */ | |
a973e9dd | 1452 | while (unlikely(c->freelist)) { |
894b8788 CL |
1453 | void **object; |
1454 | ||
7c2e132c CL |
1455 | tail = 0; /* Hot objects. Put the slab first */ |
1456 | ||
894b8788 | 1457 | /* Retrieve object from cpu_freelist */ |
dfb4f096 | 1458 | object = c->freelist; |
b3fba8da | 1459 | c->freelist = c->freelist[c->offset]; |
894b8788 CL |
1460 | |
1461 | /* And put onto the regular freelist */ | |
b3fba8da | 1462 | object[c->offset] = page->freelist; |
894b8788 CL |
1463 | page->freelist = object; |
1464 | page->inuse--; | |
1465 | } | |
dfb4f096 | 1466 | c->page = NULL; |
7c2e132c | 1467 | unfreeze_slab(s, page, tail); |
81819f0f CL |
1468 | } |
1469 | ||
dfb4f096 | 1470 | static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c) |
81819f0f | 1471 | { |
8ff12cfc | 1472 | stat(c, CPUSLAB_FLUSH); |
dfb4f096 CL |
1473 | slab_lock(c->page); |
1474 | deactivate_slab(s, c); | |
81819f0f CL |
1475 | } |
1476 | ||
1477 | /* | |
1478 | * Flush cpu slab. | |
6446faa2 | 1479 | * |
81819f0f CL |
1480 | * Called from IPI handler with interrupts disabled. |
1481 | */ | |
0c710013 | 1482 | static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu) |
81819f0f | 1483 | { |
dfb4f096 | 1484 | struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); |
81819f0f | 1485 | |
dfb4f096 CL |
1486 | if (likely(c && c->page)) |
1487 | flush_slab(s, c); | |
81819f0f CL |
1488 | } |
1489 | ||
1490 | static void flush_cpu_slab(void *d) | |
1491 | { | |
1492 | struct kmem_cache *s = d; | |
81819f0f | 1493 | |
dfb4f096 | 1494 | __flush_cpu_slab(s, smp_processor_id()); |
81819f0f CL |
1495 | } |
1496 | ||
1497 | static void flush_all(struct kmem_cache *s) | |
1498 | { | |
1499 | #ifdef CONFIG_SMP | |
1500 | on_each_cpu(flush_cpu_slab, s, 1, 1); | |
1501 | #else | |
1502 | unsigned long flags; | |
1503 | ||
1504 | local_irq_save(flags); | |
1505 | flush_cpu_slab(s); | |
1506 | local_irq_restore(flags); | |
1507 | #endif | |
1508 | } | |
1509 | ||
dfb4f096 CL |
1510 | /* |
1511 | * Check if the objects in a per cpu structure fit numa | |
1512 | * locality expectations. | |
1513 | */ | |
1514 | static inline int node_match(struct kmem_cache_cpu *c, int node) | |
1515 | { | |
1516 | #ifdef CONFIG_NUMA | |
1517 | if (node != -1 && c->node != node) | |
1518 | return 0; | |
1519 | #endif | |
1520 | return 1; | |
1521 | } | |
1522 | ||
81819f0f | 1523 | /* |
894b8788 CL |
1524 | * Slow path. The lockless freelist is empty or we need to perform |
1525 | * debugging duties. | |
1526 | * | |
1527 | * Interrupts are disabled. | |
81819f0f | 1528 | * |
894b8788 CL |
1529 | * Processing is still very fast if new objects have been freed to the |
1530 | * regular freelist. In that case we simply take over the regular freelist | |
1531 | * as the lockless freelist and zap the regular freelist. | |
81819f0f | 1532 | * |
894b8788 CL |
1533 | * If that is not working then we fall back to the partial lists. We take the |
1534 | * first element of the freelist as the object to allocate now and move the | |
1535 | * rest of the freelist to the lockless freelist. | |
81819f0f | 1536 | * |
894b8788 | 1537 | * And if we were unable to get a new slab from the partial slab lists then |
6446faa2 CL |
1538 | * we need to allocate a new slab. This is the slowest path since it involves |
1539 | * a call to the page allocator and the setup of a new slab. | |
81819f0f | 1540 | */ |
894b8788 | 1541 | static void *__slab_alloc(struct kmem_cache *s, |
dfb4f096 | 1542 | gfp_t gfpflags, int node, void *addr, struct kmem_cache_cpu *c) |
81819f0f | 1543 | { |
81819f0f | 1544 | void **object; |
dfb4f096 | 1545 | struct page *new; |
81819f0f | 1546 | |
e72e9c23 LT |
1547 | /* We handle __GFP_ZERO in the caller */ |
1548 | gfpflags &= ~__GFP_ZERO; | |
1549 | ||
dfb4f096 | 1550 | if (!c->page) |
81819f0f CL |
1551 | goto new_slab; |
1552 | ||
dfb4f096 CL |
1553 | slab_lock(c->page); |
1554 | if (unlikely(!node_match(c, node))) | |
81819f0f | 1555 | goto another_slab; |
6446faa2 | 1556 | |
8ff12cfc | 1557 | stat(c, ALLOC_REFILL); |
6446faa2 | 1558 | |
894b8788 | 1559 | load_freelist: |
dfb4f096 | 1560 | object = c->page->freelist; |
a973e9dd | 1561 | if (unlikely(!object)) |
81819f0f | 1562 | goto another_slab; |
dfb4f096 | 1563 | if (unlikely(SlabDebug(c->page))) |
81819f0f CL |
1564 | goto debug; |
1565 | ||
b3fba8da | 1566 | c->freelist = object[c->offset]; |
39b26464 | 1567 | c->page->inuse = c->page->objects; |
a973e9dd | 1568 | c->page->freelist = NULL; |
dfb4f096 | 1569 | c->node = page_to_nid(c->page); |
1f84260c | 1570 | unlock_out: |
dfb4f096 | 1571 | slab_unlock(c->page); |
8ff12cfc | 1572 | stat(c, ALLOC_SLOWPATH); |
81819f0f CL |
1573 | return object; |
1574 | ||
1575 | another_slab: | |
dfb4f096 | 1576 | deactivate_slab(s, c); |
81819f0f CL |
1577 | |
1578 | new_slab: | |
dfb4f096 CL |
1579 | new = get_partial(s, gfpflags, node); |
1580 | if (new) { | |
1581 | c->page = new; | |
8ff12cfc | 1582 | stat(c, ALLOC_FROM_PARTIAL); |
894b8788 | 1583 | goto load_freelist; |
81819f0f CL |
1584 | } |
1585 | ||
b811c202 CL |
1586 | if (gfpflags & __GFP_WAIT) |
1587 | local_irq_enable(); | |
1588 | ||
dfb4f096 | 1589 | new = new_slab(s, gfpflags, node); |
b811c202 CL |
1590 | |
1591 | if (gfpflags & __GFP_WAIT) | |
1592 | local_irq_disable(); | |
1593 | ||
dfb4f096 CL |
1594 | if (new) { |
1595 | c = get_cpu_slab(s, smp_processor_id()); | |
8ff12cfc | 1596 | stat(c, ALLOC_SLAB); |
05aa3450 | 1597 | if (c->page) |
dfb4f096 | 1598 | flush_slab(s, c); |
dfb4f096 CL |
1599 | slab_lock(new); |
1600 | SetSlabFrozen(new); | |
1601 | c->page = new; | |
4b6f0750 | 1602 | goto load_freelist; |
81819f0f | 1603 | } |
71c7a06f | 1604 | return NULL; |
81819f0f | 1605 | debug: |
dfb4f096 | 1606 | if (!alloc_debug_processing(s, c->page, object, addr)) |
81819f0f | 1607 | goto another_slab; |
894b8788 | 1608 | |
dfb4f096 | 1609 | c->page->inuse++; |
b3fba8da | 1610 | c->page->freelist = object[c->offset]; |
ee3c72a1 | 1611 | c->node = -1; |
1f84260c | 1612 | goto unlock_out; |
894b8788 CL |
1613 | } |
1614 | ||
1615 | /* | |
1616 | * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc) | |
1617 | * have the fastpath folded into their functions. So no function call | |
1618 | * overhead for requests that can be satisfied on the fastpath. | |
1619 | * | |
1620 | * The fastpath works by first checking if the lockless freelist can be used. | |
1621 | * If not then __slab_alloc is called for slow processing. | |
1622 | * | |
1623 | * Otherwise we can simply pick the next object from the lockless free list. | |
1624 | */ | |
06428780 | 1625 | static __always_inline void *slab_alloc(struct kmem_cache *s, |
ce15fea8 | 1626 | gfp_t gfpflags, int node, void *addr) |
894b8788 | 1627 | { |
894b8788 | 1628 | void **object; |
dfb4f096 | 1629 | struct kmem_cache_cpu *c; |
1f84260c | 1630 | unsigned long flags; |
bdb21928 | 1631 | unsigned int objsize; |
1f84260c | 1632 | |
894b8788 | 1633 | local_irq_save(flags); |
dfb4f096 | 1634 | c = get_cpu_slab(s, smp_processor_id()); |
bdb21928 | 1635 | objsize = c->objsize; |
a973e9dd | 1636 | if (unlikely(!c->freelist || !node_match(c, node))) |
894b8788 | 1637 | |
dfb4f096 | 1638 | object = __slab_alloc(s, gfpflags, node, addr, c); |
894b8788 CL |
1639 | |
1640 | else { | |
dfb4f096 | 1641 | object = c->freelist; |
b3fba8da | 1642 | c->freelist = object[c->offset]; |
8ff12cfc | 1643 | stat(c, ALLOC_FASTPATH); |
894b8788 CL |
1644 | } |
1645 | local_irq_restore(flags); | |
d07dbea4 CL |
1646 | |
1647 | if (unlikely((gfpflags & __GFP_ZERO) && object)) | |
bdb21928 | 1648 | memset(object, 0, objsize); |
d07dbea4 | 1649 | |
894b8788 | 1650 | return object; |
81819f0f CL |
1651 | } |
1652 | ||
1653 | void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags) | |
1654 | { | |
ce15fea8 | 1655 | return slab_alloc(s, gfpflags, -1, __builtin_return_address(0)); |
81819f0f CL |
1656 | } |
1657 | EXPORT_SYMBOL(kmem_cache_alloc); | |
1658 | ||
1659 | #ifdef CONFIG_NUMA | |
1660 | void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node) | |
1661 | { | |
ce15fea8 | 1662 | return slab_alloc(s, gfpflags, node, __builtin_return_address(0)); |
81819f0f CL |
1663 | } |
1664 | EXPORT_SYMBOL(kmem_cache_alloc_node); | |
1665 | #endif | |
1666 | ||
1667 | /* | |
894b8788 CL |
1668 | * Slow patch handling. This may still be called frequently since objects |
1669 | * have a longer lifetime than the cpu slabs in most processing loads. | |
81819f0f | 1670 | * |
894b8788 CL |
1671 | * So we still attempt to reduce cache line usage. Just take the slab |
1672 | * lock and free the item. If there is no additional partial page | |
1673 | * handling required then we can return immediately. | |
81819f0f | 1674 | */ |
894b8788 | 1675 | static void __slab_free(struct kmem_cache *s, struct page *page, |
b3fba8da | 1676 | void *x, void *addr, unsigned int offset) |
81819f0f CL |
1677 | { |
1678 | void *prior; | |
1679 | void **object = (void *)x; | |
8ff12cfc | 1680 | struct kmem_cache_cpu *c; |
81819f0f | 1681 | |
8ff12cfc CL |
1682 | c = get_cpu_slab(s, raw_smp_processor_id()); |
1683 | stat(c, FREE_SLOWPATH); | |
81819f0f CL |
1684 | slab_lock(page); |
1685 | ||
35e5d7ee | 1686 | if (unlikely(SlabDebug(page))) |
81819f0f | 1687 | goto debug; |
6446faa2 | 1688 | |
81819f0f | 1689 | checks_ok: |
b3fba8da | 1690 | prior = object[offset] = page->freelist; |
81819f0f CL |
1691 | page->freelist = object; |
1692 | page->inuse--; | |
1693 | ||
8ff12cfc CL |
1694 | if (unlikely(SlabFrozen(page))) { |
1695 | stat(c, FREE_FROZEN); | |
81819f0f | 1696 | goto out_unlock; |
8ff12cfc | 1697 | } |
81819f0f CL |
1698 | |
1699 | if (unlikely(!page->inuse)) | |
1700 | goto slab_empty; | |
1701 | ||
1702 | /* | |
6446faa2 | 1703 | * Objects left in the slab. If it was not on the partial list before |
81819f0f CL |
1704 | * then add it. |
1705 | */ | |
a973e9dd | 1706 | if (unlikely(!prior)) { |
7c2e132c | 1707 | add_partial(get_node(s, page_to_nid(page)), page, 1); |
8ff12cfc CL |
1708 | stat(c, FREE_ADD_PARTIAL); |
1709 | } | |
81819f0f CL |
1710 | |
1711 | out_unlock: | |
1712 | slab_unlock(page); | |
81819f0f CL |
1713 | return; |
1714 | ||
1715 | slab_empty: | |
a973e9dd | 1716 | if (prior) { |
81819f0f | 1717 | /* |
672bba3a | 1718 | * Slab still on the partial list. |
81819f0f CL |
1719 | */ |
1720 | remove_partial(s, page); | |
8ff12cfc CL |
1721 | stat(c, FREE_REMOVE_PARTIAL); |
1722 | } | |
81819f0f | 1723 | slab_unlock(page); |
8ff12cfc | 1724 | stat(c, FREE_SLAB); |
81819f0f | 1725 | discard_slab(s, page); |
81819f0f CL |
1726 | return; |
1727 | ||
1728 | debug: | |
3ec09742 | 1729 | if (!free_debug_processing(s, page, x, addr)) |
77c5e2d0 | 1730 | goto out_unlock; |
77c5e2d0 | 1731 | goto checks_ok; |
81819f0f CL |
1732 | } |
1733 | ||
894b8788 CL |
1734 | /* |
1735 | * Fastpath with forced inlining to produce a kfree and kmem_cache_free that | |
1736 | * can perform fastpath freeing without additional function calls. | |
1737 | * | |
1738 | * The fastpath is only possible if we are freeing to the current cpu slab | |
1739 | * of this processor. This typically the case if we have just allocated | |
1740 | * the item before. | |
1741 | * | |
1742 | * If fastpath is not possible then fall back to __slab_free where we deal | |
1743 | * with all sorts of special processing. | |
1744 | */ | |
06428780 | 1745 | static __always_inline void slab_free(struct kmem_cache *s, |
894b8788 CL |
1746 | struct page *page, void *x, void *addr) |
1747 | { | |
1748 | void **object = (void *)x; | |
dfb4f096 | 1749 | struct kmem_cache_cpu *c; |
1f84260c CL |
1750 | unsigned long flags; |
1751 | ||
894b8788 | 1752 | local_irq_save(flags); |
dfb4f096 | 1753 | c = get_cpu_slab(s, smp_processor_id()); |
27d9e4e9 | 1754 | debug_check_no_locks_freed(object, c->objsize); |
3ac7fe5a TG |
1755 | if (!(s->flags & SLAB_DEBUG_OBJECTS)) |
1756 | debug_check_no_obj_freed(object, s->objsize); | |
ee3c72a1 | 1757 | if (likely(page == c->page && c->node >= 0)) { |
b3fba8da | 1758 | object[c->offset] = c->freelist; |
dfb4f096 | 1759 | c->freelist = object; |
8ff12cfc | 1760 | stat(c, FREE_FASTPATH); |
894b8788 | 1761 | } else |
b3fba8da | 1762 | __slab_free(s, page, x, addr, c->offset); |
894b8788 CL |
1763 | |
1764 | local_irq_restore(flags); | |
1765 | } | |
1766 | ||
81819f0f CL |
1767 | void kmem_cache_free(struct kmem_cache *s, void *x) |
1768 | { | |
77c5e2d0 | 1769 | struct page *page; |
81819f0f | 1770 | |
b49af68f | 1771 | page = virt_to_head_page(x); |
81819f0f | 1772 | |
77c5e2d0 | 1773 | slab_free(s, page, x, __builtin_return_address(0)); |
81819f0f CL |
1774 | } |
1775 | EXPORT_SYMBOL(kmem_cache_free); | |
1776 | ||
1777 | /* Figure out on which slab object the object resides */ | |
1778 | static struct page *get_object_page(const void *x) | |
1779 | { | |
b49af68f | 1780 | struct page *page = virt_to_head_page(x); |
81819f0f CL |
1781 | |
1782 | if (!PageSlab(page)) | |
1783 | return NULL; | |
1784 | ||
1785 | return page; | |
1786 | } | |
1787 | ||
1788 | /* | |
672bba3a CL |
1789 | * Object placement in a slab is made very easy because we always start at |
1790 | * offset 0. If we tune the size of the object to the alignment then we can | |
1791 | * get the required alignment by putting one properly sized object after | |
1792 | * another. | |
81819f0f CL |
1793 | * |
1794 | * Notice that the allocation order determines the sizes of the per cpu | |
1795 | * caches. Each processor has always one slab available for allocations. | |
1796 | * Increasing the allocation order reduces the number of times that slabs | |
672bba3a | 1797 | * must be moved on and off the partial lists and is therefore a factor in |
81819f0f | 1798 | * locking overhead. |
81819f0f CL |
1799 | */ |
1800 | ||
1801 | /* | |
1802 | * Mininum / Maximum order of slab pages. This influences locking overhead | |
1803 | * and slab fragmentation. A higher order reduces the number of partial slabs | |
1804 | * and increases the number of allocations possible without having to | |
1805 | * take the list_lock. | |
1806 | */ | |
1807 | static int slub_min_order; | |
114e9e89 | 1808 | static int slub_max_order = PAGE_ALLOC_COSTLY_ORDER; |
9b2cd506 | 1809 | static int slub_min_objects; |
81819f0f CL |
1810 | |
1811 | /* | |
1812 | * Merge control. If this is set then no merging of slab caches will occur. | |
672bba3a | 1813 | * (Could be removed. This was introduced to pacify the merge skeptics.) |
81819f0f CL |
1814 | */ |
1815 | static int slub_nomerge; | |
1816 | ||
81819f0f CL |
1817 | /* |
1818 | * Calculate the order of allocation given an slab object size. | |
1819 | * | |
672bba3a CL |
1820 | * The order of allocation has significant impact on performance and other |
1821 | * system components. Generally order 0 allocations should be preferred since | |
1822 | * order 0 does not cause fragmentation in the page allocator. Larger objects | |
1823 | * be problematic to put into order 0 slabs because there may be too much | |
c124f5b5 | 1824 | * unused space left. We go to a higher order if more than 1/16th of the slab |
672bba3a CL |
1825 | * would be wasted. |
1826 | * | |
1827 | * In order to reach satisfactory performance we must ensure that a minimum | |
1828 | * number of objects is in one slab. Otherwise we may generate too much | |
1829 | * activity on the partial lists which requires taking the list_lock. This is | |
1830 | * less a concern for large slabs though which are rarely used. | |
81819f0f | 1831 | * |
672bba3a CL |
1832 | * slub_max_order specifies the order where we begin to stop considering the |
1833 | * number of objects in a slab as critical. If we reach slub_max_order then | |
1834 | * we try to keep the page order as low as possible. So we accept more waste | |
1835 | * of space in favor of a small page order. | |
81819f0f | 1836 | * |
672bba3a CL |
1837 | * Higher order allocations also allow the placement of more objects in a |
1838 | * slab and thereby reduce object handling overhead. If the user has | |
1839 | * requested a higher mininum order then we start with that one instead of | |
1840 | * the smallest order which will fit the object. | |
81819f0f | 1841 | */ |
5e6d444e CL |
1842 | static inline int slab_order(int size, int min_objects, |
1843 | int max_order, int fract_leftover) | |
81819f0f CL |
1844 | { |
1845 | int order; | |
1846 | int rem; | |
6300ea75 | 1847 | int min_order = slub_min_order; |
81819f0f | 1848 | |
39b26464 CL |
1849 | if ((PAGE_SIZE << min_order) / size > 65535) |
1850 | return get_order(size * 65535) - 1; | |
1851 | ||
6300ea75 | 1852 | for (order = max(min_order, |
5e6d444e CL |
1853 | fls(min_objects * size - 1) - PAGE_SHIFT); |
1854 | order <= max_order; order++) { | |
81819f0f | 1855 | |
5e6d444e | 1856 | unsigned long slab_size = PAGE_SIZE << order; |
81819f0f | 1857 | |
5e6d444e | 1858 | if (slab_size < min_objects * size) |
81819f0f CL |
1859 | continue; |
1860 | ||
1861 | rem = slab_size % size; | |
1862 | ||
5e6d444e | 1863 | if (rem <= slab_size / fract_leftover) |
81819f0f CL |
1864 | break; |
1865 | ||
1866 | } | |
672bba3a | 1867 | |
81819f0f CL |
1868 | return order; |
1869 | } | |
1870 | ||
5e6d444e CL |
1871 | static inline int calculate_order(int size) |
1872 | { | |
1873 | int order; | |
1874 | int min_objects; | |
1875 | int fraction; | |
1876 | ||
1877 | /* | |
1878 | * Attempt to find best configuration for a slab. This | |
1879 | * works by first attempting to generate a layout with | |
1880 | * the best configuration and backing off gradually. | |
1881 | * | |
1882 | * First we reduce the acceptable waste in a slab. Then | |
1883 | * we reduce the minimum objects required in a slab. | |
1884 | */ | |
1885 | min_objects = slub_min_objects; | |
9b2cd506 CL |
1886 | if (!min_objects) |
1887 | min_objects = 4 * (fls(nr_cpu_ids) + 1); | |
5e6d444e | 1888 | while (min_objects > 1) { |
c124f5b5 | 1889 | fraction = 16; |
5e6d444e CL |
1890 | while (fraction >= 4) { |
1891 | order = slab_order(size, min_objects, | |
1892 | slub_max_order, fraction); | |
1893 | if (order <= slub_max_order) | |
1894 | return order; | |
1895 | fraction /= 2; | |
1896 | } | |
1897 | min_objects /= 2; | |
1898 | } | |
1899 | ||
1900 | /* | |
1901 | * We were unable to place multiple objects in a slab. Now | |
1902 | * lets see if we can place a single object there. | |
1903 | */ | |
1904 | order = slab_order(size, 1, slub_max_order, 1); | |
1905 | if (order <= slub_max_order) | |
1906 | return order; | |
1907 | ||
1908 | /* | |
1909 | * Doh this slab cannot be placed using slub_max_order. | |
1910 | */ | |
1911 | order = slab_order(size, 1, MAX_ORDER, 1); | |
1912 | if (order <= MAX_ORDER) | |
1913 | return order; | |
1914 | return -ENOSYS; | |
1915 | } | |
1916 | ||
81819f0f | 1917 | /* |
672bba3a | 1918 | * Figure out what the alignment of the objects will be. |
81819f0f CL |
1919 | */ |
1920 | static unsigned long calculate_alignment(unsigned long flags, | |
1921 | unsigned long align, unsigned long size) | |
1922 | { | |
1923 | /* | |
6446faa2 CL |
1924 | * If the user wants hardware cache aligned objects then follow that |
1925 | * suggestion if the object is sufficiently large. | |
81819f0f | 1926 | * |
6446faa2 CL |
1927 | * The hardware cache alignment cannot override the specified |
1928 | * alignment though. If that is greater then use it. | |
81819f0f | 1929 | */ |
b6210386 NP |
1930 | if (flags & SLAB_HWCACHE_ALIGN) { |
1931 | unsigned long ralign = cache_line_size(); | |
1932 | while (size <= ralign / 2) | |
1933 | ralign /= 2; | |
1934 | align = max(align, ralign); | |
1935 | } | |
81819f0f CL |
1936 | |
1937 | if (align < ARCH_SLAB_MINALIGN) | |
b6210386 | 1938 | align = ARCH_SLAB_MINALIGN; |
81819f0f CL |
1939 | |
1940 | return ALIGN(align, sizeof(void *)); | |
1941 | } | |
1942 | ||
dfb4f096 CL |
1943 | static void init_kmem_cache_cpu(struct kmem_cache *s, |
1944 | struct kmem_cache_cpu *c) | |
1945 | { | |
1946 | c->page = NULL; | |
a973e9dd | 1947 | c->freelist = NULL; |
dfb4f096 | 1948 | c->node = 0; |
42a9fdbb CL |
1949 | c->offset = s->offset / sizeof(void *); |
1950 | c->objsize = s->objsize; | |
62f75532 PE |
1951 | #ifdef CONFIG_SLUB_STATS |
1952 | memset(c->stat, 0, NR_SLUB_STAT_ITEMS * sizeof(unsigned)); | |
1953 | #endif | |
dfb4f096 CL |
1954 | } |
1955 | ||
81819f0f CL |
1956 | static void init_kmem_cache_node(struct kmem_cache_node *n) |
1957 | { | |
1958 | n->nr_partial = 0; | |
81819f0f CL |
1959 | spin_lock_init(&n->list_lock); |
1960 | INIT_LIST_HEAD(&n->partial); | |
8ab1372f | 1961 | #ifdef CONFIG_SLUB_DEBUG |
0f389ec6 | 1962 | atomic_long_set(&n->nr_slabs, 0); |
643b1138 | 1963 | INIT_LIST_HEAD(&n->full); |
8ab1372f | 1964 | #endif |
81819f0f CL |
1965 | } |
1966 | ||
4c93c355 CL |
1967 | #ifdef CONFIG_SMP |
1968 | /* | |
1969 | * Per cpu array for per cpu structures. | |
1970 | * | |
1971 | * The per cpu array places all kmem_cache_cpu structures from one processor | |
1972 | * close together meaning that it becomes possible that multiple per cpu | |
1973 | * structures are contained in one cacheline. This may be particularly | |
1974 | * beneficial for the kmalloc caches. | |
1975 | * | |
1976 | * A desktop system typically has around 60-80 slabs. With 100 here we are | |
1977 | * likely able to get per cpu structures for all caches from the array defined | |
1978 | * here. We must be able to cover all kmalloc caches during bootstrap. | |
1979 | * | |
1980 | * If the per cpu array is exhausted then fall back to kmalloc | |
1981 | * of individual cachelines. No sharing is possible then. | |
1982 | */ | |
1983 | #define NR_KMEM_CACHE_CPU 100 | |
1984 | ||
1985 | static DEFINE_PER_CPU(struct kmem_cache_cpu, | |
1986 | kmem_cache_cpu)[NR_KMEM_CACHE_CPU]; | |
1987 | ||
1988 | static DEFINE_PER_CPU(struct kmem_cache_cpu *, kmem_cache_cpu_free); | |
1989 | static cpumask_t kmem_cach_cpu_free_init_once = CPU_MASK_NONE; | |
1990 | ||
1991 | static struct kmem_cache_cpu *alloc_kmem_cache_cpu(struct kmem_cache *s, | |
1992 | int cpu, gfp_t flags) | |
1993 | { | |
1994 | struct kmem_cache_cpu *c = per_cpu(kmem_cache_cpu_free, cpu); | |
1995 | ||
1996 | if (c) | |
1997 | per_cpu(kmem_cache_cpu_free, cpu) = | |
1998 | (void *)c->freelist; | |
1999 | else { | |
2000 | /* Table overflow: So allocate ourselves */ | |
2001 | c = kmalloc_node( | |
2002 | ALIGN(sizeof(struct kmem_cache_cpu), cache_line_size()), | |
2003 | flags, cpu_to_node(cpu)); | |
2004 | if (!c) | |
2005 | return NULL; | |
2006 | } | |
2007 | ||
2008 | init_kmem_cache_cpu(s, c); | |
2009 | return c; | |
2010 | } | |
2011 | ||
2012 | static void free_kmem_cache_cpu(struct kmem_cache_cpu *c, int cpu) | |
2013 | { | |
2014 | if (c < per_cpu(kmem_cache_cpu, cpu) || | |
2015 | c > per_cpu(kmem_cache_cpu, cpu) + NR_KMEM_CACHE_CPU) { | |
2016 | kfree(c); | |
2017 | return; | |
2018 | } | |
2019 | c->freelist = (void *)per_cpu(kmem_cache_cpu_free, cpu); | |
2020 | per_cpu(kmem_cache_cpu_free, cpu) = c; | |
2021 | } | |
2022 | ||
2023 | static void free_kmem_cache_cpus(struct kmem_cache *s) | |
2024 | { | |
2025 | int cpu; | |
2026 | ||
2027 | for_each_online_cpu(cpu) { | |
2028 | struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); | |
2029 | ||
2030 | if (c) { | |
2031 | s->cpu_slab[cpu] = NULL; | |
2032 | free_kmem_cache_cpu(c, cpu); | |
2033 | } | |
2034 | } | |
2035 | } | |
2036 | ||
2037 | static int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags) | |
2038 | { | |
2039 | int cpu; | |
2040 | ||
2041 | for_each_online_cpu(cpu) { | |
2042 | struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); | |
2043 | ||
2044 | if (c) | |
2045 | continue; | |
2046 | ||
2047 | c = alloc_kmem_cache_cpu(s, cpu, flags); | |
2048 | if (!c) { | |
2049 | free_kmem_cache_cpus(s); | |
2050 | return 0; | |
2051 | } | |
2052 | s->cpu_slab[cpu] = c; | |
2053 | } | |
2054 | return 1; | |
2055 | } | |
2056 | ||
2057 | /* | |
2058 | * Initialize the per cpu array. | |
2059 | */ | |
2060 | static void init_alloc_cpu_cpu(int cpu) | |
2061 | { | |
2062 | int i; | |
2063 | ||
2064 | if (cpu_isset(cpu, kmem_cach_cpu_free_init_once)) | |
2065 | return; | |
2066 | ||
2067 | for (i = NR_KMEM_CACHE_CPU - 1; i >= 0; i--) | |
2068 | free_kmem_cache_cpu(&per_cpu(kmem_cache_cpu, cpu)[i], cpu); | |
2069 | ||
2070 | cpu_set(cpu, kmem_cach_cpu_free_init_once); | |
2071 | } | |
2072 | ||
2073 | static void __init init_alloc_cpu(void) | |
2074 | { | |
2075 | int cpu; | |
2076 | ||
2077 | for_each_online_cpu(cpu) | |
2078 | init_alloc_cpu_cpu(cpu); | |
2079 | } | |
2080 | ||
2081 | #else | |
2082 | static inline void free_kmem_cache_cpus(struct kmem_cache *s) {} | |
2083 | static inline void init_alloc_cpu(void) {} | |
2084 | ||
2085 | static inline int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags) | |
2086 | { | |
2087 | init_kmem_cache_cpu(s, &s->cpu_slab); | |
2088 | return 1; | |
2089 | } | |
2090 | #endif | |
2091 | ||
81819f0f CL |
2092 | #ifdef CONFIG_NUMA |
2093 | /* | |
2094 | * No kmalloc_node yet so do it by hand. We know that this is the first | |
2095 | * slab on the node for this slabcache. There are no concurrent accesses | |
2096 | * possible. | |
2097 | * | |
2098 | * Note that this function only works on the kmalloc_node_cache | |
4c93c355 CL |
2099 | * when allocating for the kmalloc_node_cache. This is used for bootstrapping |
2100 | * memory on a fresh node that has no slab structures yet. | |
81819f0f | 2101 | */ |
1cd7daa5 AB |
2102 | static struct kmem_cache_node *early_kmem_cache_node_alloc(gfp_t gfpflags, |
2103 | int node) | |
81819f0f CL |
2104 | { |
2105 | struct page *page; | |
2106 | struct kmem_cache_node *n; | |
ba84c73c | 2107 | unsigned long flags; |
81819f0f CL |
2108 | |
2109 | BUG_ON(kmalloc_caches->size < sizeof(struct kmem_cache_node)); | |
2110 | ||
a2f92ee7 | 2111 | page = new_slab(kmalloc_caches, gfpflags, node); |
81819f0f CL |
2112 | |
2113 | BUG_ON(!page); | |
a2f92ee7 CL |
2114 | if (page_to_nid(page) != node) { |
2115 | printk(KERN_ERR "SLUB: Unable to allocate memory from " | |
2116 | "node %d\n", node); | |
2117 | printk(KERN_ERR "SLUB: Allocating a useless per node structure " | |
2118 | "in order to be able to continue\n"); | |
2119 | } | |
2120 | ||
81819f0f CL |
2121 | n = page->freelist; |
2122 | BUG_ON(!n); | |
2123 | page->freelist = get_freepointer(kmalloc_caches, n); | |
2124 | page->inuse++; | |
2125 | kmalloc_caches->node[node] = n; | |
8ab1372f | 2126 | #ifdef CONFIG_SLUB_DEBUG |
d45f39cb CL |
2127 | init_object(kmalloc_caches, n, 1); |
2128 | init_tracking(kmalloc_caches, n); | |
8ab1372f | 2129 | #endif |
81819f0f | 2130 | init_kmem_cache_node(n); |
205ab99d | 2131 | inc_slabs_node(kmalloc_caches, node, page->objects); |
6446faa2 | 2132 | |
ba84c73c | 2133 | /* |
2134 | * lockdep requires consistent irq usage for each lock | |
2135 | * so even though there cannot be a race this early in | |
2136 | * the boot sequence, we still disable irqs. | |
2137 | */ | |
2138 | local_irq_save(flags); | |
7c2e132c | 2139 | add_partial(n, page, 0); |
ba84c73c | 2140 | local_irq_restore(flags); |
81819f0f CL |
2141 | return n; |
2142 | } | |
2143 | ||
2144 | static void free_kmem_cache_nodes(struct kmem_cache *s) | |
2145 | { | |
2146 | int node; | |
2147 | ||
f64dc58c | 2148 | for_each_node_state(node, N_NORMAL_MEMORY) { |
81819f0f CL |
2149 | struct kmem_cache_node *n = s->node[node]; |
2150 | if (n && n != &s->local_node) | |
2151 | kmem_cache_free(kmalloc_caches, n); | |
2152 | s->node[node] = NULL; | |
2153 | } | |
2154 | } | |
2155 | ||
2156 | static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags) | |
2157 | { | |
2158 | int node; | |
2159 | int local_node; | |
2160 | ||
2161 | if (slab_state >= UP) | |
2162 | local_node = page_to_nid(virt_to_page(s)); | |
2163 | else | |
2164 | local_node = 0; | |
2165 | ||
f64dc58c | 2166 | for_each_node_state(node, N_NORMAL_MEMORY) { |
81819f0f CL |
2167 | struct kmem_cache_node *n; |
2168 | ||
2169 | if (local_node == node) | |
2170 | n = &s->local_node; | |
2171 | else { | |
2172 | if (slab_state == DOWN) { | |
2173 | n = early_kmem_cache_node_alloc(gfpflags, | |
2174 | node); | |
2175 | continue; | |
2176 | } | |
2177 | n = kmem_cache_alloc_node(kmalloc_caches, | |
2178 | gfpflags, node); | |
2179 | ||
2180 | if (!n) { | |
2181 | free_kmem_cache_nodes(s); | |
2182 | return 0; | |
2183 | } | |
2184 | ||
2185 | } | |
2186 | s->node[node] = n; | |
2187 | init_kmem_cache_node(n); | |
2188 | } | |
2189 | return 1; | |
2190 | } | |
2191 | #else | |
2192 | static void free_kmem_cache_nodes(struct kmem_cache *s) | |
2193 | { | |
2194 | } | |
2195 | ||
2196 | static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags) | |
2197 | { | |
2198 | init_kmem_cache_node(&s->local_node); | |
2199 | return 1; | |
2200 | } | |
2201 | #endif | |
2202 | ||
2203 | /* | |
2204 | * calculate_sizes() determines the order and the distribution of data within | |
2205 | * a slab object. | |
2206 | */ | |
06b285dc | 2207 | static int calculate_sizes(struct kmem_cache *s, int forced_order) |
81819f0f CL |
2208 | { |
2209 | unsigned long flags = s->flags; | |
2210 | unsigned long size = s->objsize; | |
2211 | unsigned long align = s->align; | |
834f3d11 | 2212 | int order; |
81819f0f | 2213 | |
d8b42bf5 CL |
2214 | /* |
2215 | * Round up object size to the next word boundary. We can only | |
2216 | * place the free pointer at word boundaries and this determines | |
2217 | * the possible location of the free pointer. | |
2218 | */ | |
2219 | size = ALIGN(size, sizeof(void *)); | |
2220 | ||
2221 | #ifdef CONFIG_SLUB_DEBUG | |
81819f0f CL |
2222 | /* |
2223 | * Determine if we can poison the object itself. If the user of | |
2224 | * the slab may touch the object after free or before allocation | |
2225 | * then we should never poison the object itself. | |
2226 | */ | |
2227 | if ((flags & SLAB_POISON) && !(flags & SLAB_DESTROY_BY_RCU) && | |
c59def9f | 2228 | !s->ctor) |
81819f0f CL |
2229 | s->flags |= __OBJECT_POISON; |
2230 | else | |
2231 | s->flags &= ~__OBJECT_POISON; | |
2232 | ||
81819f0f CL |
2233 | |
2234 | /* | |
672bba3a | 2235 | * If we are Redzoning then check if there is some space between the |
81819f0f | 2236 | * end of the object and the free pointer. If not then add an |
672bba3a | 2237 | * additional word to have some bytes to store Redzone information. |
81819f0f CL |
2238 | */ |
2239 | if ((flags & SLAB_RED_ZONE) && size == s->objsize) | |
2240 | size += sizeof(void *); | |
41ecc55b | 2241 | #endif |
81819f0f CL |
2242 | |
2243 | /* | |
672bba3a CL |
2244 | * With that we have determined the number of bytes in actual use |
2245 | * by the object. This is the potential offset to the free pointer. | |
81819f0f CL |
2246 | */ |
2247 | s->inuse = size; | |
2248 | ||
2249 | if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) || | |
c59def9f | 2250 | s->ctor)) { |
81819f0f CL |
2251 | /* |
2252 | * Relocate free pointer after the object if it is not | |
2253 | * permitted to overwrite the first word of the object on | |
2254 | * kmem_cache_free. | |
2255 | * | |
2256 | * This is the case if we do RCU, have a constructor or | |
2257 | * destructor or are poisoning the objects. | |
2258 | */ | |
2259 | s->offset = size; | |
2260 | size += sizeof(void *); | |
2261 | } | |
2262 | ||
c12b3c62 | 2263 | #ifdef CONFIG_SLUB_DEBUG |
81819f0f CL |
2264 | if (flags & SLAB_STORE_USER) |
2265 | /* | |
2266 | * Need to store information about allocs and frees after | |
2267 | * the object. | |
2268 | */ | |
2269 | size += 2 * sizeof(struct track); | |
2270 | ||
be7b3fbc | 2271 | if (flags & SLAB_RED_ZONE) |
81819f0f CL |
2272 | /* |
2273 | * Add some empty padding so that we can catch | |
2274 | * overwrites from earlier objects rather than let | |
2275 | * tracking information or the free pointer be | |
2276 | * corrupted if an user writes before the start | |
2277 | * of the object. | |
2278 | */ | |
2279 | size += sizeof(void *); | |
41ecc55b | 2280 | #endif |
672bba3a | 2281 | |
81819f0f CL |
2282 | /* |
2283 | * Determine the alignment based on various parameters that the | |
65c02d4c CL |
2284 | * user specified and the dynamic determination of cache line size |
2285 | * on bootup. | |
81819f0f CL |
2286 | */ |
2287 | align = calculate_alignment(flags, align, s->objsize); | |
2288 | ||
2289 | /* | |
2290 | * SLUB stores one object immediately after another beginning from | |
2291 | * offset 0. In order to align the objects we have to simply size | |
2292 | * each object to conform to the alignment. | |
2293 | */ | |
2294 | size = ALIGN(size, align); | |
2295 | s->size = size; | |
06b285dc CL |
2296 | if (forced_order >= 0) |
2297 | order = forced_order; | |
2298 | else | |
2299 | order = calculate_order(size); | |
81819f0f | 2300 | |
834f3d11 | 2301 | if (order < 0) |
81819f0f CL |
2302 | return 0; |
2303 | ||
b7a49f0d | 2304 | s->allocflags = 0; |
834f3d11 | 2305 | if (order) |
b7a49f0d CL |
2306 | s->allocflags |= __GFP_COMP; |
2307 | ||
2308 | if (s->flags & SLAB_CACHE_DMA) | |
2309 | s->allocflags |= SLUB_DMA; | |
2310 | ||
2311 | if (s->flags & SLAB_RECLAIM_ACCOUNT) | |
2312 | s->allocflags |= __GFP_RECLAIMABLE; | |
2313 | ||
81819f0f CL |
2314 | /* |
2315 | * Determine the number of objects per slab | |
2316 | */ | |
834f3d11 | 2317 | s->oo = oo_make(order, size); |
65c3376a | 2318 | s->min = oo_make(get_order(size), size); |
205ab99d CL |
2319 | if (oo_objects(s->oo) > oo_objects(s->max)) |
2320 | s->max = s->oo; | |
81819f0f | 2321 | |
834f3d11 | 2322 | return !!oo_objects(s->oo); |
81819f0f CL |
2323 | |
2324 | } | |
2325 | ||
81819f0f CL |
2326 | static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags, |
2327 | const char *name, size_t size, | |
2328 | size_t align, unsigned long flags, | |
4ba9b9d0 | 2329 | void (*ctor)(struct kmem_cache *, void *)) |
81819f0f CL |
2330 | { |
2331 | memset(s, 0, kmem_size); | |
2332 | s->name = name; | |
2333 | s->ctor = ctor; | |
81819f0f | 2334 | s->objsize = size; |
81819f0f | 2335 | s->align = align; |
ba0268a8 | 2336 | s->flags = kmem_cache_flags(size, flags, name, ctor); |
81819f0f | 2337 | |
06b285dc | 2338 | if (!calculate_sizes(s, -1)) |
81819f0f CL |
2339 | goto error; |
2340 | ||
2341 | s->refcount = 1; | |
2342 | #ifdef CONFIG_NUMA | |
9824601e | 2343 | s->remote_node_defrag_ratio = 100; |
81819f0f | 2344 | #endif |
dfb4f096 CL |
2345 | if (!init_kmem_cache_nodes(s, gfpflags & ~SLUB_DMA)) |
2346 | goto error; | |
81819f0f | 2347 | |
dfb4f096 | 2348 | if (alloc_kmem_cache_cpus(s, gfpflags & ~SLUB_DMA)) |
81819f0f | 2349 | return 1; |
4c93c355 | 2350 | free_kmem_cache_nodes(s); |
81819f0f CL |
2351 | error: |
2352 | if (flags & SLAB_PANIC) | |
2353 | panic("Cannot create slab %s size=%lu realsize=%u " | |
2354 | "order=%u offset=%u flags=%lx\n", | |
834f3d11 | 2355 | s->name, (unsigned long)size, s->size, oo_order(s->oo), |
81819f0f CL |
2356 | s->offset, flags); |
2357 | return 0; | |
2358 | } | |
81819f0f CL |
2359 | |
2360 | /* | |
2361 | * Check if a given pointer is valid | |
2362 | */ | |
2363 | int kmem_ptr_validate(struct kmem_cache *s, const void *object) | |
2364 | { | |
06428780 | 2365 | struct page *page; |
81819f0f CL |
2366 | |
2367 | page = get_object_page(object); | |
2368 | ||
2369 | if (!page || s != page->slab) | |
2370 | /* No slab or wrong slab */ | |
2371 | return 0; | |
2372 | ||
abcd08a6 | 2373 | if (!check_valid_pointer(s, page, object)) |
81819f0f CL |
2374 | return 0; |
2375 | ||
2376 | /* | |
2377 | * We could also check if the object is on the slabs freelist. | |
2378 | * But this would be too expensive and it seems that the main | |
6446faa2 | 2379 | * purpose of kmem_ptr_valid() is to check if the object belongs |
81819f0f CL |
2380 | * to a certain slab. |
2381 | */ | |
2382 | return 1; | |
2383 | } | |
2384 | EXPORT_SYMBOL(kmem_ptr_validate); | |
2385 | ||
2386 | /* | |
2387 | * Determine the size of a slab object | |
2388 | */ | |
2389 | unsigned int kmem_cache_size(struct kmem_cache *s) | |
2390 | { | |
2391 | return s->objsize; | |
2392 | } | |
2393 | EXPORT_SYMBOL(kmem_cache_size); | |
2394 | ||
2395 | const char *kmem_cache_name(struct kmem_cache *s) | |
2396 | { | |
2397 | return s->name; | |
2398 | } | |
2399 | EXPORT_SYMBOL(kmem_cache_name); | |
2400 | ||
33b12c38 CL |
2401 | static void list_slab_objects(struct kmem_cache *s, struct page *page, |
2402 | const char *text) | |
2403 | { | |
2404 | #ifdef CONFIG_SLUB_DEBUG | |
2405 | void *addr = page_address(page); | |
2406 | void *p; | |
2407 | DECLARE_BITMAP(map, page->objects); | |
2408 | ||
2409 | bitmap_zero(map, page->objects); | |
2410 | slab_err(s, page, "%s", text); | |
2411 | slab_lock(page); | |
2412 | for_each_free_object(p, s, page->freelist) | |
2413 | set_bit(slab_index(p, s, addr), map); | |
2414 | ||
2415 | for_each_object(p, s, addr, page->objects) { | |
2416 | ||
2417 | if (!test_bit(slab_index(p, s, addr), map)) { | |
2418 | printk(KERN_ERR "INFO: Object 0x%p @offset=%tu\n", | |
2419 | p, p - addr); | |
2420 | print_tracking(s, p); | |
2421 | } | |
2422 | } | |
2423 | slab_unlock(page); | |
2424 | #endif | |
2425 | } | |
2426 | ||
81819f0f | 2427 | /* |
599870b1 | 2428 | * Attempt to free all partial slabs on a node. |
81819f0f | 2429 | */ |
599870b1 | 2430 | static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n) |
81819f0f | 2431 | { |
81819f0f CL |
2432 | unsigned long flags; |
2433 | struct page *page, *h; | |
2434 | ||
2435 | spin_lock_irqsave(&n->list_lock, flags); | |
33b12c38 | 2436 | list_for_each_entry_safe(page, h, &n->partial, lru) { |
81819f0f CL |
2437 | if (!page->inuse) { |
2438 | list_del(&page->lru); | |
2439 | discard_slab(s, page); | |
599870b1 | 2440 | n->nr_partial--; |
33b12c38 CL |
2441 | } else { |
2442 | list_slab_objects(s, page, | |
2443 | "Objects remaining on kmem_cache_close()"); | |
599870b1 | 2444 | } |
33b12c38 | 2445 | } |
81819f0f | 2446 | spin_unlock_irqrestore(&n->list_lock, flags); |
81819f0f CL |
2447 | } |
2448 | ||
2449 | /* | |
672bba3a | 2450 | * Release all resources used by a slab cache. |
81819f0f | 2451 | */ |
0c710013 | 2452 | static inline int kmem_cache_close(struct kmem_cache *s) |
81819f0f CL |
2453 | { |
2454 | int node; | |
2455 | ||
2456 | flush_all(s); | |
2457 | ||
2458 | /* Attempt to free all objects */ | |
4c93c355 | 2459 | free_kmem_cache_cpus(s); |
f64dc58c | 2460 | for_each_node_state(node, N_NORMAL_MEMORY) { |
81819f0f CL |
2461 | struct kmem_cache_node *n = get_node(s, node); |
2462 | ||
599870b1 CL |
2463 | free_partial(s, n); |
2464 | if (n->nr_partial || slabs_node(s, node)) | |
81819f0f CL |
2465 | return 1; |
2466 | } | |
2467 | free_kmem_cache_nodes(s); | |
2468 | return 0; | |
2469 | } | |
2470 | ||
2471 | /* | |
2472 | * Close a cache and release the kmem_cache structure | |
2473 | * (must be used for caches created using kmem_cache_create) | |
2474 | */ | |
2475 | void kmem_cache_destroy(struct kmem_cache *s) | |
2476 | { | |
2477 | down_write(&slub_lock); | |
2478 | s->refcount--; | |
2479 | if (!s->refcount) { | |
2480 | list_del(&s->list); | |
a0e1d1be | 2481 | up_write(&slub_lock); |
d629d819 PE |
2482 | if (kmem_cache_close(s)) { |
2483 | printk(KERN_ERR "SLUB %s: %s called for cache that " | |
2484 | "still has objects.\n", s->name, __func__); | |
2485 | dump_stack(); | |
2486 | } | |
81819f0f | 2487 | sysfs_slab_remove(s); |
a0e1d1be CL |
2488 | } else |
2489 | up_write(&slub_lock); | |
81819f0f CL |
2490 | } |
2491 | EXPORT_SYMBOL(kmem_cache_destroy); | |
2492 | ||
2493 | /******************************************************************** | |
2494 | * Kmalloc subsystem | |
2495 | *******************************************************************/ | |
2496 | ||
331dc558 | 2497 | struct kmem_cache kmalloc_caches[PAGE_SHIFT + 1] __cacheline_aligned; |
81819f0f CL |
2498 | EXPORT_SYMBOL(kmalloc_caches); |
2499 | ||
81819f0f CL |
2500 | static int __init setup_slub_min_order(char *str) |
2501 | { | |
06428780 | 2502 | get_option(&str, &slub_min_order); |
81819f0f CL |
2503 | |
2504 | return 1; | |
2505 | } | |
2506 | ||
2507 | __setup("slub_min_order=", setup_slub_min_order); | |
2508 | ||
2509 | static int __init setup_slub_max_order(char *str) | |
2510 | { | |
06428780 | 2511 | get_option(&str, &slub_max_order); |
81819f0f CL |
2512 | |
2513 | return 1; | |
2514 | } | |
2515 | ||
2516 | __setup("slub_max_order=", setup_slub_max_order); | |
2517 | ||
2518 | static int __init setup_slub_min_objects(char *str) | |
2519 | { | |
06428780 | 2520 | get_option(&str, &slub_min_objects); |
81819f0f CL |
2521 | |
2522 | return 1; | |
2523 | } | |
2524 | ||
2525 | __setup("slub_min_objects=", setup_slub_min_objects); | |
2526 | ||
2527 | static int __init setup_slub_nomerge(char *str) | |
2528 | { | |
2529 | slub_nomerge = 1; | |
2530 | return 1; | |
2531 | } | |
2532 | ||
2533 | __setup("slub_nomerge", setup_slub_nomerge); | |
2534 | ||
81819f0f CL |
2535 | static struct kmem_cache *create_kmalloc_cache(struct kmem_cache *s, |
2536 | const char *name, int size, gfp_t gfp_flags) | |
2537 | { | |
2538 | unsigned int flags = 0; | |
2539 | ||
2540 | if (gfp_flags & SLUB_DMA) | |
2541 | flags = SLAB_CACHE_DMA; | |
2542 | ||
2543 | down_write(&slub_lock); | |
2544 | if (!kmem_cache_open(s, gfp_flags, name, size, ARCH_KMALLOC_MINALIGN, | |
319d1e24 | 2545 | flags, NULL)) |
81819f0f CL |
2546 | goto panic; |
2547 | ||
2548 | list_add(&s->list, &slab_caches); | |
2549 | up_write(&slub_lock); | |
2550 | if (sysfs_slab_add(s)) | |
2551 | goto panic; | |
2552 | return s; | |
2553 | ||
2554 | panic: | |
2555 | panic("Creation of kmalloc slab %s size=%d failed.\n", name, size); | |
2556 | } | |
2557 | ||
2e443fd0 | 2558 | #ifdef CONFIG_ZONE_DMA |
4097d601 | 2559 | static struct kmem_cache *kmalloc_caches_dma[PAGE_SHIFT + 1]; |
1ceef402 CL |
2560 | |
2561 | static void sysfs_add_func(struct work_struct *w) | |
2562 | { | |
2563 | struct kmem_cache *s; | |
2564 | ||
2565 | down_write(&slub_lock); | |
2566 | list_for_each_entry(s, &slab_caches, list) { | |
2567 | if (s->flags & __SYSFS_ADD_DEFERRED) { | |
2568 | s->flags &= ~__SYSFS_ADD_DEFERRED; | |
2569 | sysfs_slab_add(s); | |
2570 | } | |
2571 | } | |
2572 | up_write(&slub_lock); | |
2573 | } | |
2574 | ||
2575 | static DECLARE_WORK(sysfs_add_work, sysfs_add_func); | |
2576 | ||
2e443fd0 CL |
2577 | static noinline struct kmem_cache *dma_kmalloc_cache(int index, gfp_t flags) |
2578 | { | |
2579 | struct kmem_cache *s; | |
2e443fd0 CL |
2580 | char *text; |
2581 | size_t realsize; | |
2582 | ||
2583 | s = kmalloc_caches_dma[index]; | |
2584 | if (s) | |
2585 | return s; | |
2586 | ||
2587 | /* Dynamically create dma cache */ | |
1ceef402 CL |
2588 | if (flags & __GFP_WAIT) |
2589 | down_write(&slub_lock); | |
2590 | else { | |
2591 | if (!down_write_trylock(&slub_lock)) | |
2592 | goto out; | |
2593 | } | |
2594 | ||
2595 | if (kmalloc_caches_dma[index]) | |
2596 | goto unlock_out; | |
2e443fd0 | 2597 | |
7b55f620 | 2598 | realsize = kmalloc_caches[index].objsize; |
3adbefee IM |
2599 | text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d", |
2600 | (unsigned int)realsize); | |
1ceef402 CL |
2601 | s = kmalloc(kmem_size, flags & ~SLUB_DMA); |
2602 | ||
2603 | if (!s || !text || !kmem_cache_open(s, flags, text, | |
2604 | realsize, ARCH_KMALLOC_MINALIGN, | |
2605 | SLAB_CACHE_DMA|__SYSFS_ADD_DEFERRED, NULL)) { | |
2606 | kfree(s); | |
2607 | kfree(text); | |
2608 | goto unlock_out; | |
dfce8648 | 2609 | } |
1ceef402 CL |
2610 | |
2611 | list_add(&s->list, &slab_caches); | |
2612 | kmalloc_caches_dma[index] = s; | |
2613 | ||
2614 | schedule_work(&sysfs_add_work); | |
2615 | ||
2616 | unlock_out: | |
dfce8648 | 2617 | up_write(&slub_lock); |
1ceef402 | 2618 | out: |
dfce8648 | 2619 | return kmalloc_caches_dma[index]; |
2e443fd0 CL |
2620 | } |
2621 | #endif | |
2622 | ||
f1b26339 CL |
2623 | /* |
2624 | * Conversion table for small slabs sizes / 8 to the index in the | |
2625 | * kmalloc array. This is necessary for slabs < 192 since we have non power | |
2626 | * of two cache sizes there. The size of larger slabs can be determined using | |
2627 | * fls. | |
2628 | */ | |
2629 | static s8 size_index[24] = { | |
2630 | 3, /* 8 */ | |
2631 | 4, /* 16 */ | |
2632 | 5, /* 24 */ | |
2633 | 5, /* 32 */ | |
2634 | 6, /* 40 */ | |
2635 | 6, /* 48 */ | |
2636 | 6, /* 56 */ | |
2637 | 6, /* 64 */ | |
2638 | 1, /* 72 */ | |
2639 | 1, /* 80 */ | |
2640 | 1, /* 88 */ | |
2641 | 1, /* 96 */ | |
2642 | 7, /* 104 */ | |
2643 | 7, /* 112 */ | |
2644 | 7, /* 120 */ | |
2645 | 7, /* 128 */ | |
2646 | 2, /* 136 */ | |
2647 | 2, /* 144 */ | |
2648 | 2, /* 152 */ | |
2649 | 2, /* 160 */ | |
2650 | 2, /* 168 */ | |
2651 | 2, /* 176 */ | |
2652 | 2, /* 184 */ | |
2653 | 2 /* 192 */ | |
2654 | }; | |
2655 | ||
81819f0f CL |
2656 | static struct kmem_cache *get_slab(size_t size, gfp_t flags) |
2657 | { | |
f1b26339 | 2658 | int index; |
81819f0f | 2659 | |
f1b26339 CL |
2660 | if (size <= 192) { |
2661 | if (!size) | |
2662 | return ZERO_SIZE_PTR; | |
81819f0f | 2663 | |
f1b26339 | 2664 | index = size_index[(size - 1) / 8]; |
aadb4bc4 | 2665 | } else |
f1b26339 | 2666 | index = fls(size - 1); |
81819f0f CL |
2667 | |
2668 | #ifdef CONFIG_ZONE_DMA | |
f1b26339 | 2669 | if (unlikely((flags & SLUB_DMA))) |
2e443fd0 | 2670 | return dma_kmalloc_cache(index, flags); |
f1b26339 | 2671 | |
81819f0f CL |
2672 | #endif |
2673 | return &kmalloc_caches[index]; | |
2674 | } | |
2675 | ||
2676 | void *__kmalloc(size_t size, gfp_t flags) | |
2677 | { | |
aadb4bc4 | 2678 | struct kmem_cache *s; |
81819f0f | 2679 | |
331dc558 | 2680 | if (unlikely(size > PAGE_SIZE)) |
eada35ef | 2681 | return kmalloc_large(size, flags); |
aadb4bc4 CL |
2682 | |
2683 | s = get_slab(size, flags); | |
2684 | ||
2685 | if (unlikely(ZERO_OR_NULL_PTR(s))) | |
6cb8f913 CL |
2686 | return s; |
2687 | ||
ce15fea8 | 2688 | return slab_alloc(s, flags, -1, __builtin_return_address(0)); |
81819f0f CL |
2689 | } |
2690 | EXPORT_SYMBOL(__kmalloc); | |
2691 | ||
f619cfe1 CL |
2692 | static void *kmalloc_large_node(size_t size, gfp_t flags, int node) |
2693 | { | |
2694 | struct page *page = alloc_pages_node(node, flags | __GFP_COMP, | |
2695 | get_order(size)); | |
2696 | ||
2697 | if (page) | |
2698 | return page_address(page); | |
2699 | else | |
2700 | return NULL; | |
2701 | } | |
2702 | ||
81819f0f CL |
2703 | #ifdef CONFIG_NUMA |
2704 | void *__kmalloc_node(size_t size, gfp_t flags, int node) | |
2705 | { | |
aadb4bc4 | 2706 | struct kmem_cache *s; |
81819f0f | 2707 | |
331dc558 | 2708 | if (unlikely(size > PAGE_SIZE)) |
f619cfe1 | 2709 | return kmalloc_large_node(size, flags, node); |
aadb4bc4 CL |
2710 | |
2711 | s = get_slab(size, flags); | |
2712 | ||
2713 | if (unlikely(ZERO_OR_NULL_PTR(s))) | |
6cb8f913 CL |
2714 | return s; |
2715 | ||
ce15fea8 | 2716 | return slab_alloc(s, flags, node, __builtin_return_address(0)); |
81819f0f CL |
2717 | } |
2718 | EXPORT_SYMBOL(__kmalloc_node); | |
2719 | #endif | |
2720 | ||
2721 | size_t ksize(const void *object) | |
2722 | { | |
272c1d21 | 2723 | struct page *page; |
81819f0f CL |
2724 | struct kmem_cache *s; |
2725 | ||
ef8b4520 | 2726 | if (unlikely(object == ZERO_SIZE_PTR)) |
272c1d21 CL |
2727 | return 0; |
2728 | ||
294a80a8 | 2729 | page = virt_to_head_page(object); |
294a80a8 | 2730 | |
76994412 PE |
2731 | if (unlikely(!PageSlab(page))) { |
2732 | WARN_ON(!PageCompound(page)); | |
294a80a8 | 2733 | return PAGE_SIZE << compound_order(page); |
76994412 | 2734 | } |
81819f0f | 2735 | s = page->slab; |
81819f0f | 2736 | |
ae20bfda | 2737 | #ifdef CONFIG_SLUB_DEBUG |
81819f0f CL |
2738 | /* |
2739 | * Debugging requires use of the padding between object | |
2740 | * and whatever may come after it. | |
2741 | */ | |
2742 | if (s->flags & (SLAB_RED_ZONE | SLAB_POISON)) | |
2743 | return s->objsize; | |
2744 | ||
ae20bfda | 2745 | #endif |
81819f0f CL |
2746 | /* |
2747 | * If we have the need to store the freelist pointer | |
2748 | * back there or track user information then we can | |
2749 | * only use the space before that information. | |
2750 | */ | |
2751 | if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER)) | |
2752 | return s->inuse; | |
81819f0f CL |
2753 | /* |
2754 | * Else we can use all the padding etc for the allocation | |
2755 | */ | |
2756 | return s->size; | |
2757 | } | |
2758 | EXPORT_SYMBOL(ksize); | |
2759 | ||
2760 | void kfree(const void *x) | |
2761 | { | |
81819f0f | 2762 | struct page *page; |
5bb983b0 | 2763 | void *object = (void *)x; |
81819f0f | 2764 | |
2408c550 | 2765 | if (unlikely(ZERO_OR_NULL_PTR(x))) |
81819f0f CL |
2766 | return; |
2767 | ||
b49af68f | 2768 | page = virt_to_head_page(x); |
aadb4bc4 CL |
2769 | if (unlikely(!PageSlab(page))) { |
2770 | put_page(page); | |
2771 | return; | |
2772 | } | |
5bb983b0 | 2773 | slab_free(page->slab, page, object, __builtin_return_address(0)); |
81819f0f CL |
2774 | } |
2775 | EXPORT_SYMBOL(kfree); | |
2776 | ||
2086d26a | 2777 | /* |
672bba3a CL |
2778 | * kmem_cache_shrink removes empty slabs from the partial lists and sorts |
2779 | * the remaining slabs by the number of items in use. The slabs with the | |
2780 | * most items in use come first. New allocations will then fill those up | |
2781 | * and thus they can be removed from the partial lists. | |
2782 | * | |
2783 | * The slabs with the least items are placed last. This results in them | |
2784 | * being allocated from last increasing the chance that the last objects | |
2785 | * are freed in them. | |
2086d26a CL |
2786 | */ |
2787 | int kmem_cache_shrink(struct kmem_cache *s) | |
2788 | { | |
2789 | int node; | |
2790 | int i; | |
2791 | struct kmem_cache_node *n; | |
2792 | struct page *page; | |
2793 | struct page *t; | |
205ab99d | 2794 | int objects = oo_objects(s->max); |
2086d26a | 2795 | struct list_head *slabs_by_inuse = |
834f3d11 | 2796 | kmalloc(sizeof(struct list_head) * objects, GFP_KERNEL); |
2086d26a CL |
2797 | unsigned long flags; |
2798 | ||
2799 | if (!slabs_by_inuse) | |
2800 | return -ENOMEM; | |
2801 | ||
2802 | flush_all(s); | |
f64dc58c | 2803 | for_each_node_state(node, N_NORMAL_MEMORY) { |
2086d26a CL |
2804 | n = get_node(s, node); |
2805 | ||
2806 | if (!n->nr_partial) | |
2807 | continue; | |
2808 | ||
834f3d11 | 2809 | for (i = 0; i < objects; i++) |
2086d26a CL |
2810 | INIT_LIST_HEAD(slabs_by_inuse + i); |
2811 | ||
2812 | spin_lock_irqsave(&n->list_lock, flags); | |
2813 | ||
2814 | /* | |
672bba3a | 2815 | * Build lists indexed by the items in use in each slab. |
2086d26a | 2816 | * |
672bba3a CL |
2817 | * Note that concurrent frees may occur while we hold the |
2818 | * list_lock. page->inuse here is the upper limit. | |
2086d26a CL |
2819 | */ |
2820 | list_for_each_entry_safe(page, t, &n->partial, lru) { | |
2821 | if (!page->inuse && slab_trylock(page)) { | |
2822 | /* | |
2823 | * Must hold slab lock here because slab_free | |
2824 | * may have freed the last object and be | |
2825 | * waiting to release the slab. | |
2826 | */ | |
2827 | list_del(&page->lru); | |
2828 | n->nr_partial--; | |
2829 | slab_unlock(page); | |
2830 | discard_slab(s, page); | |
2831 | } else { | |
fcda3d89 CL |
2832 | list_move(&page->lru, |
2833 | slabs_by_inuse + page->inuse); | |
2086d26a CL |
2834 | } |
2835 | } | |
2836 | ||
2086d26a | 2837 | /* |
672bba3a CL |
2838 | * Rebuild the partial list with the slabs filled up most |
2839 | * first and the least used slabs at the end. | |
2086d26a | 2840 | */ |
834f3d11 | 2841 | for (i = objects - 1; i >= 0; i--) |
2086d26a CL |
2842 | list_splice(slabs_by_inuse + i, n->partial.prev); |
2843 | ||
2086d26a CL |
2844 | spin_unlock_irqrestore(&n->list_lock, flags); |
2845 | } | |
2846 | ||
2847 | kfree(slabs_by_inuse); | |
2848 | return 0; | |
2849 | } | |
2850 | EXPORT_SYMBOL(kmem_cache_shrink); | |
2851 | ||
b9049e23 YG |
2852 | #if defined(CONFIG_NUMA) && defined(CONFIG_MEMORY_HOTPLUG) |
2853 | static int slab_mem_going_offline_callback(void *arg) | |
2854 | { | |
2855 | struct kmem_cache *s; | |
2856 | ||
2857 | down_read(&slub_lock); | |
2858 | list_for_each_entry(s, &slab_caches, list) | |
2859 | kmem_cache_shrink(s); | |
2860 | up_read(&slub_lock); | |
2861 | ||
2862 | return 0; | |
2863 | } | |
2864 | ||
2865 | static void slab_mem_offline_callback(void *arg) | |
2866 | { | |
2867 | struct kmem_cache_node *n; | |
2868 | struct kmem_cache *s; | |
2869 | struct memory_notify *marg = arg; | |
2870 | int offline_node; | |
2871 | ||
2872 | offline_node = marg->status_change_nid; | |
2873 | ||
2874 | /* | |
2875 | * If the node still has available memory. we need kmem_cache_node | |
2876 | * for it yet. | |
2877 | */ | |
2878 | if (offline_node < 0) | |
2879 | return; | |
2880 | ||
2881 | down_read(&slub_lock); | |
2882 | list_for_each_entry(s, &slab_caches, list) { | |
2883 | n = get_node(s, offline_node); | |
2884 | if (n) { | |
2885 | /* | |
2886 | * if n->nr_slabs > 0, slabs still exist on the node | |
2887 | * that is going down. We were unable to free them, | |
2888 | * and offline_pages() function shoudn't call this | |
2889 | * callback. So, we must fail. | |
2890 | */ | |
0f389ec6 | 2891 | BUG_ON(slabs_node(s, offline_node)); |
b9049e23 YG |
2892 | |
2893 | s->node[offline_node] = NULL; | |
2894 | kmem_cache_free(kmalloc_caches, n); | |
2895 | } | |
2896 | } | |
2897 | up_read(&slub_lock); | |
2898 | } | |
2899 | ||
2900 | static int slab_mem_going_online_callback(void *arg) | |
2901 | { | |
2902 | struct kmem_cache_node *n; | |
2903 | struct kmem_cache *s; | |
2904 | struct memory_notify *marg = arg; | |
2905 | int nid = marg->status_change_nid; | |
2906 | int ret = 0; | |
2907 | ||
2908 | /* | |
2909 | * If the node's memory is already available, then kmem_cache_node is | |
2910 | * already created. Nothing to do. | |
2911 | */ | |
2912 | if (nid < 0) | |
2913 | return 0; | |
2914 | ||
2915 | /* | |
0121c619 | 2916 | * We are bringing a node online. No memory is available yet. We must |
b9049e23 YG |
2917 | * allocate a kmem_cache_node structure in order to bring the node |
2918 | * online. | |
2919 | */ | |
2920 | down_read(&slub_lock); | |
2921 | list_for_each_entry(s, &slab_caches, list) { | |
2922 | /* | |
2923 | * XXX: kmem_cache_alloc_node will fallback to other nodes | |
2924 | * since memory is not yet available from the node that | |
2925 | * is brought up. | |
2926 | */ | |
2927 | n = kmem_cache_alloc(kmalloc_caches, GFP_KERNEL); | |
2928 | if (!n) { | |
2929 | ret = -ENOMEM; | |
2930 | goto out; | |
2931 | } | |
2932 | init_kmem_cache_node(n); | |
2933 | s->node[nid] = n; | |
2934 | } | |
2935 | out: | |
2936 | up_read(&slub_lock); | |
2937 | return ret; | |
2938 | } | |
2939 | ||
2940 | static int slab_memory_callback(struct notifier_block *self, | |
2941 | unsigned long action, void *arg) | |
2942 | { | |
2943 | int ret = 0; | |
2944 | ||
2945 | switch (action) { | |
2946 | case MEM_GOING_ONLINE: | |
2947 | ret = slab_mem_going_online_callback(arg); | |
2948 | break; | |
2949 | case MEM_GOING_OFFLINE: | |
2950 | ret = slab_mem_going_offline_callback(arg); | |
2951 | break; | |
2952 | case MEM_OFFLINE: | |
2953 | case MEM_CANCEL_ONLINE: | |
2954 | slab_mem_offline_callback(arg); | |
2955 | break; | |
2956 | case MEM_ONLINE: | |
2957 | case MEM_CANCEL_OFFLINE: | |
2958 | break; | |
2959 | } | |
2960 | ||
2961 | ret = notifier_from_errno(ret); | |
2962 | return ret; | |
2963 | } | |
2964 | ||
2965 | #endif /* CONFIG_MEMORY_HOTPLUG */ | |
2966 | ||
81819f0f CL |
2967 | /******************************************************************** |
2968 | * Basic setup of slabs | |
2969 | *******************************************************************/ | |
2970 | ||
2971 | void __init kmem_cache_init(void) | |
2972 | { | |
2973 | int i; | |
4b356be0 | 2974 | int caches = 0; |
81819f0f | 2975 | |
4c93c355 CL |
2976 | init_alloc_cpu(); |
2977 | ||
81819f0f CL |
2978 | #ifdef CONFIG_NUMA |
2979 | /* | |
2980 | * Must first have the slab cache available for the allocations of the | |
672bba3a | 2981 | * struct kmem_cache_node's. There is special bootstrap code in |
81819f0f CL |
2982 | * kmem_cache_open for slab_state == DOWN. |
2983 | */ | |
2984 | create_kmalloc_cache(&kmalloc_caches[0], "kmem_cache_node", | |
2985 | sizeof(struct kmem_cache_node), GFP_KERNEL); | |
8ffa6875 | 2986 | kmalloc_caches[0].refcount = -1; |
4b356be0 | 2987 | caches++; |
b9049e23 | 2988 | |
0c40ba4f | 2989 | hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI); |
81819f0f CL |
2990 | #endif |
2991 | ||
2992 | /* Able to allocate the per node structures */ | |
2993 | slab_state = PARTIAL; | |
2994 | ||
2995 | /* Caches that are not of the two-to-the-power-of size */ | |
4b356be0 CL |
2996 | if (KMALLOC_MIN_SIZE <= 64) { |
2997 | create_kmalloc_cache(&kmalloc_caches[1], | |
81819f0f | 2998 | "kmalloc-96", 96, GFP_KERNEL); |
4b356be0 | 2999 | caches++; |
4b356be0 | 3000 | create_kmalloc_cache(&kmalloc_caches[2], |
81819f0f | 3001 | "kmalloc-192", 192, GFP_KERNEL); |
4b356be0 CL |
3002 | caches++; |
3003 | } | |
81819f0f | 3004 | |
331dc558 | 3005 | for (i = KMALLOC_SHIFT_LOW; i <= PAGE_SHIFT; i++) { |
81819f0f CL |
3006 | create_kmalloc_cache(&kmalloc_caches[i], |
3007 | "kmalloc", 1 << i, GFP_KERNEL); | |
4b356be0 CL |
3008 | caches++; |
3009 | } | |
81819f0f | 3010 | |
f1b26339 CL |
3011 | |
3012 | /* | |
3013 | * Patch up the size_index table if we have strange large alignment | |
3014 | * requirements for the kmalloc array. This is only the case for | |
6446faa2 | 3015 | * MIPS it seems. The standard arches will not generate any code here. |
f1b26339 CL |
3016 | * |
3017 | * Largest permitted alignment is 256 bytes due to the way we | |
3018 | * handle the index determination for the smaller caches. | |
3019 | * | |
3020 | * Make sure that nothing crazy happens if someone starts tinkering | |
3021 | * around with ARCH_KMALLOC_MINALIGN | |
3022 | */ | |
3023 | BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 || | |
3024 | (KMALLOC_MIN_SIZE & (KMALLOC_MIN_SIZE - 1))); | |
3025 | ||
12ad6843 | 3026 | for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) |
f1b26339 CL |
3027 | size_index[(i - 1) / 8] = KMALLOC_SHIFT_LOW; |
3028 | ||
41d54d3b CL |
3029 | if (KMALLOC_MIN_SIZE == 128) { |
3030 | /* | |
3031 | * The 192 byte sized cache is not used if the alignment | |
3032 | * is 128 byte. Redirect kmalloc to use the 256 byte cache | |
3033 | * instead. | |
3034 | */ | |
3035 | for (i = 128 + 8; i <= 192; i += 8) | |
3036 | size_index[(i - 1) / 8] = 8; | |
3037 | } | |
3038 | ||
81819f0f CL |
3039 | slab_state = UP; |
3040 | ||
3041 | /* Provide the correct kmalloc names now that the caches are up */ | |
331dc558 | 3042 | for (i = KMALLOC_SHIFT_LOW; i <= PAGE_SHIFT; i++) |
81819f0f CL |
3043 | kmalloc_caches[i]. name = |
3044 | kasprintf(GFP_KERNEL, "kmalloc-%d", 1 << i); | |
3045 | ||
3046 | #ifdef CONFIG_SMP | |
3047 | register_cpu_notifier(&slab_notifier); | |
4c93c355 CL |
3048 | kmem_size = offsetof(struct kmem_cache, cpu_slab) + |
3049 | nr_cpu_ids * sizeof(struct kmem_cache_cpu *); | |
3050 | #else | |
3051 | kmem_size = sizeof(struct kmem_cache); | |
81819f0f CL |
3052 | #endif |
3053 | ||
3adbefee IM |
3054 | printk(KERN_INFO |
3055 | "SLUB: Genslabs=%d, HWalign=%d, Order=%d-%d, MinObjects=%d," | |
4b356be0 CL |
3056 | " CPUs=%d, Nodes=%d\n", |
3057 | caches, cache_line_size(), | |
81819f0f CL |
3058 | slub_min_order, slub_max_order, slub_min_objects, |
3059 | nr_cpu_ids, nr_node_ids); | |
3060 | } | |
3061 | ||
3062 | /* | |
3063 | * Find a mergeable slab cache | |
3064 | */ | |
3065 | static int slab_unmergeable(struct kmem_cache *s) | |
3066 | { | |
3067 | if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE)) | |
3068 | return 1; | |
3069 | ||
c59def9f | 3070 | if (s->ctor) |
81819f0f CL |
3071 | return 1; |
3072 | ||
8ffa6875 CL |
3073 | /* |
3074 | * We may have set a slab to be unmergeable during bootstrap. | |
3075 | */ | |
3076 | if (s->refcount < 0) | |
3077 | return 1; | |
3078 | ||
81819f0f CL |
3079 | return 0; |
3080 | } | |
3081 | ||
3082 | static struct kmem_cache *find_mergeable(size_t size, | |
ba0268a8 | 3083 | size_t align, unsigned long flags, const char *name, |
4ba9b9d0 | 3084 | void (*ctor)(struct kmem_cache *, void *)) |
81819f0f | 3085 | { |
5b95a4ac | 3086 | struct kmem_cache *s; |
81819f0f CL |
3087 | |
3088 | if (slub_nomerge || (flags & SLUB_NEVER_MERGE)) | |
3089 | return NULL; | |
3090 | ||
c59def9f | 3091 | if (ctor) |
81819f0f CL |
3092 | return NULL; |
3093 | ||
3094 | size = ALIGN(size, sizeof(void *)); | |
3095 | align = calculate_alignment(flags, align, size); | |
3096 | size = ALIGN(size, align); | |
ba0268a8 | 3097 | flags = kmem_cache_flags(size, flags, name, NULL); |
81819f0f | 3098 | |
5b95a4ac | 3099 | list_for_each_entry(s, &slab_caches, list) { |
81819f0f CL |
3100 | if (slab_unmergeable(s)) |
3101 | continue; | |
3102 | ||
3103 | if (size > s->size) | |
3104 | continue; | |
3105 | ||
ba0268a8 | 3106 | if ((flags & SLUB_MERGE_SAME) != (s->flags & SLUB_MERGE_SAME)) |
81819f0f CL |
3107 | continue; |
3108 | /* | |
3109 | * Check if alignment is compatible. | |
3110 | * Courtesy of Adrian Drzewiecki | |
3111 | */ | |
06428780 | 3112 | if ((s->size & ~(align - 1)) != s->size) |
81819f0f CL |
3113 | continue; |
3114 | ||
3115 | if (s->size - size >= sizeof(void *)) | |
3116 | continue; | |
3117 | ||
3118 | return s; | |
3119 | } | |
3120 | return NULL; | |
3121 | } | |
3122 | ||
3123 | struct kmem_cache *kmem_cache_create(const char *name, size_t size, | |
3124 | size_t align, unsigned long flags, | |
4ba9b9d0 | 3125 | void (*ctor)(struct kmem_cache *, void *)) |
81819f0f CL |
3126 | { |
3127 | struct kmem_cache *s; | |
3128 | ||
3129 | down_write(&slub_lock); | |
ba0268a8 | 3130 | s = find_mergeable(size, align, flags, name, ctor); |
81819f0f | 3131 | if (s) { |
42a9fdbb CL |
3132 | int cpu; |
3133 | ||
81819f0f CL |
3134 | s->refcount++; |
3135 | /* | |
3136 | * Adjust the object sizes so that we clear | |
3137 | * the complete object on kzalloc. | |
3138 | */ | |
3139 | s->objsize = max(s->objsize, (int)size); | |
42a9fdbb CL |
3140 | |
3141 | /* | |
3142 | * And then we need to update the object size in the | |
3143 | * per cpu structures | |
3144 | */ | |
3145 | for_each_online_cpu(cpu) | |
3146 | get_cpu_slab(s, cpu)->objsize = s->objsize; | |
6446faa2 | 3147 | |
81819f0f | 3148 | s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *))); |
a0e1d1be | 3149 | up_write(&slub_lock); |
6446faa2 | 3150 | |
81819f0f CL |
3151 | if (sysfs_slab_alias(s, name)) |
3152 | goto err; | |
a0e1d1be CL |
3153 | return s; |
3154 | } | |
6446faa2 | 3155 | |
a0e1d1be CL |
3156 | s = kmalloc(kmem_size, GFP_KERNEL); |
3157 | if (s) { | |
3158 | if (kmem_cache_open(s, GFP_KERNEL, name, | |
c59def9f | 3159 | size, align, flags, ctor)) { |
81819f0f | 3160 | list_add(&s->list, &slab_caches); |
a0e1d1be CL |
3161 | up_write(&slub_lock); |
3162 | if (sysfs_slab_add(s)) | |
3163 | goto err; | |
3164 | return s; | |
3165 | } | |
3166 | kfree(s); | |
81819f0f CL |
3167 | } |
3168 | up_write(&slub_lock); | |
81819f0f CL |
3169 | |
3170 | err: | |
81819f0f CL |
3171 | if (flags & SLAB_PANIC) |
3172 | panic("Cannot create slabcache %s\n", name); | |
3173 | else | |
3174 | s = NULL; | |
3175 | return s; | |
3176 | } | |
3177 | EXPORT_SYMBOL(kmem_cache_create); | |
3178 | ||
81819f0f | 3179 | #ifdef CONFIG_SMP |
81819f0f | 3180 | /* |
672bba3a CL |
3181 | * Use the cpu notifier to insure that the cpu slabs are flushed when |
3182 | * necessary. | |
81819f0f CL |
3183 | */ |
3184 | static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb, | |
3185 | unsigned long action, void *hcpu) | |
3186 | { | |
3187 | long cpu = (long)hcpu; | |
5b95a4ac CL |
3188 | struct kmem_cache *s; |
3189 | unsigned long flags; | |
81819f0f CL |
3190 | |
3191 | switch (action) { | |
4c93c355 CL |
3192 | case CPU_UP_PREPARE: |
3193 | case CPU_UP_PREPARE_FROZEN: | |
3194 | init_alloc_cpu_cpu(cpu); | |
3195 | down_read(&slub_lock); | |
3196 | list_for_each_entry(s, &slab_caches, list) | |
3197 | s->cpu_slab[cpu] = alloc_kmem_cache_cpu(s, cpu, | |
3198 | GFP_KERNEL); | |
3199 | up_read(&slub_lock); | |
3200 | break; | |
3201 | ||
81819f0f | 3202 | case CPU_UP_CANCELED: |
8bb78442 | 3203 | case CPU_UP_CANCELED_FROZEN: |
81819f0f | 3204 | case CPU_DEAD: |
8bb78442 | 3205 | case CPU_DEAD_FROZEN: |
5b95a4ac CL |
3206 | down_read(&slub_lock); |
3207 | list_for_each_entry(s, &slab_caches, list) { | |
4c93c355 CL |
3208 | struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); |
3209 | ||
5b95a4ac CL |
3210 | local_irq_save(flags); |
3211 | __flush_cpu_slab(s, cpu); | |
3212 | local_irq_restore(flags); | |
4c93c355 CL |
3213 | free_kmem_cache_cpu(c, cpu); |
3214 | s->cpu_slab[cpu] = NULL; | |
5b95a4ac CL |
3215 | } |
3216 | up_read(&slub_lock); | |
81819f0f CL |
3217 | break; |
3218 | default: | |
3219 | break; | |
3220 | } | |
3221 | return NOTIFY_OK; | |
3222 | } | |
3223 | ||
06428780 | 3224 | static struct notifier_block __cpuinitdata slab_notifier = { |
3adbefee | 3225 | .notifier_call = slab_cpuup_callback |
06428780 | 3226 | }; |
81819f0f CL |
3227 | |
3228 | #endif | |
3229 | ||
81819f0f CL |
3230 | void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, void *caller) |
3231 | { | |
aadb4bc4 CL |
3232 | struct kmem_cache *s; |
3233 | ||
331dc558 | 3234 | if (unlikely(size > PAGE_SIZE)) |
eada35ef PE |
3235 | return kmalloc_large(size, gfpflags); |
3236 | ||
aadb4bc4 | 3237 | s = get_slab(size, gfpflags); |
81819f0f | 3238 | |
2408c550 | 3239 | if (unlikely(ZERO_OR_NULL_PTR(s))) |
6cb8f913 | 3240 | return s; |
81819f0f | 3241 | |
ce15fea8 | 3242 | return slab_alloc(s, gfpflags, -1, caller); |
81819f0f CL |
3243 | } |
3244 | ||
3245 | void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags, | |
3246 | int node, void *caller) | |
3247 | { | |
aadb4bc4 CL |
3248 | struct kmem_cache *s; |
3249 | ||
331dc558 | 3250 | if (unlikely(size > PAGE_SIZE)) |
f619cfe1 | 3251 | return kmalloc_large_node(size, gfpflags, node); |
eada35ef | 3252 | |
aadb4bc4 | 3253 | s = get_slab(size, gfpflags); |
81819f0f | 3254 | |
2408c550 | 3255 | if (unlikely(ZERO_OR_NULL_PTR(s))) |
6cb8f913 | 3256 | return s; |
81819f0f | 3257 | |
ce15fea8 | 3258 | return slab_alloc(s, gfpflags, node, caller); |
81819f0f CL |
3259 | } |
3260 | ||
f6acb635 | 3261 | #ifdef CONFIG_SLUB_DEBUG |
205ab99d CL |
3262 | static unsigned long count_partial(struct kmem_cache_node *n, |
3263 | int (*get_count)(struct page *)) | |
5b06c853 CL |
3264 | { |
3265 | unsigned long flags; | |
3266 | unsigned long x = 0; | |
3267 | struct page *page; | |
3268 | ||
3269 | spin_lock_irqsave(&n->list_lock, flags); | |
3270 | list_for_each_entry(page, &n->partial, lru) | |
205ab99d | 3271 | x += get_count(page); |
5b06c853 CL |
3272 | spin_unlock_irqrestore(&n->list_lock, flags); |
3273 | return x; | |
3274 | } | |
205ab99d CL |
3275 | |
3276 | static int count_inuse(struct page *page) | |
3277 | { | |
3278 | return page->inuse; | |
3279 | } | |
3280 | ||
3281 | static int count_total(struct page *page) | |
3282 | { | |
3283 | return page->objects; | |
3284 | } | |
3285 | ||
3286 | static int count_free(struct page *page) | |
3287 | { | |
3288 | return page->objects - page->inuse; | |
3289 | } | |
5b06c853 | 3290 | |
434e245d CL |
3291 | static int validate_slab(struct kmem_cache *s, struct page *page, |
3292 | unsigned long *map) | |
53e15af0 CL |
3293 | { |
3294 | void *p; | |
a973e9dd | 3295 | void *addr = page_address(page); |
53e15af0 CL |
3296 | |
3297 | if (!check_slab(s, page) || | |
3298 | !on_freelist(s, page, NULL)) | |
3299 | return 0; | |
3300 | ||
3301 | /* Now we know that a valid freelist exists */ | |
39b26464 | 3302 | bitmap_zero(map, page->objects); |
53e15af0 | 3303 | |
7656c72b CL |
3304 | for_each_free_object(p, s, page->freelist) { |
3305 | set_bit(slab_index(p, s, addr), map); | |
53e15af0 CL |
3306 | if (!check_object(s, page, p, 0)) |
3307 | return 0; | |
3308 | } | |
3309 | ||
224a88be | 3310 | for_each_object(p, s, addr, page->objects) |
7656c72b | 3311 | if (!test_bit(slab_index(p, s, addr), map)) |
53e15af0 CL |
3312 | if (!check_object(s, page, p, 1)) |
3313 | return 0; | |
3314 | return 1; | |
3315 | } | |
3316 | ||
434e245d CL |
3317 | static void validate_slab_slab(struct kmem_cache *s, struct page *page, |
3318 | unsigned long *map) | |
53e15af0 CL |
3319 | { |
3320 | if (slab_trylock(page)) { | |
434e245d | 3321 | validate_slab(s, page, map); |
53e15af0 CL |
3322 | slab_unlock(page); |
3323 | } else | |
3324 | printk(KERN_INFO "SLUB %s: Skipped busy slab 0x%p\n", | |
3325 | s->name, page); | |
3326 | ||
3327 | if (s->flags & DEBUG_DEFAULT_FLAGS) { | |
35e5d7ee CL |
3328 | if (!SlabDebug(page)) |
3329 | printk(KERN_ERR "SLUB %s: SlabDebug not set " | |
53e15af0 CL |
3330 | "on slab 0x%p\n", s->name, page); |
3331 | } else { | |
35e5d7ee CL |
3332 | if (SlabDebug(page)) |
3333 | printk(KERN_ERR "SLUB %s: SlabDebug set on " | |
53e15af0 CL |
3334 | "slab 0x%p\n", s->name, page); |
3335 | } | |
3336 | } | |
3337 | ||
434e245d CL |
3338 | static int validate_slab_node(struct kmem_cache *s, |
3339 | struct kmem_cache_node *n, unsigned long *map) | |
53e15af0 CL |
3340 | { |
3341 | unsigned long count = 0; | |
3342 | struct page *page; | |
3343 | unsigned long flags; | |
3344 | ||
3345 | spin_lock_irqsave(&n->list_lock, flags); | |
3346 | ||
3347 | list_for_each_entry(page, &n->partial, lru) { | |
434e245d | 3348 | validate_slab_slab(s, page, map); |
53e15af0 CL |
3349 | count++; |
3350 | } | |
3351 | if (count != n->nr_partial) | |
3352 | printk(KERN_ERR "SLUB %s: %ld partial slabs counted but " | |
3353 | "counter=%ld\n", s->name, count, n->nr_partial); | |
3354 | ||
3355 | if (!(s->flags & SLAB_STORE_USER)) | |
3356 | goto out; | |
3357 | ||
3358 | list_for_each_entry(page, &n->full, lru) { | |
434e245d | 3359 | validate_slab_slab(s, page, map); |
53e15af0 CL |
3360 | count++; |
3361 | } | |
3362 | if (count != atomic_long_read(&n->nr_slabs)) | |
3363 | printk(KERN_ERR "SLUB: %s %ld slabs counted but " | |
3364 | "counter=%ld\n", s->name, count, | |
3365 | atomic_long_read(&n->nr_slabs)); | |
3366 | ||
3367 | out: | |
3368 | spin_unlock_irqrestore(&n->list_lock, flags); | |
3369 | return count; | |
3370 | } | |
3371 | ||
434e245d | 3372 | static long validate_slab_cache(struct kmem_cache *s) |
53e15af0 CL |
3373 | { |
3374 | int node; | |
3375 | unsigned long count = 0; | |
205ab99d | 3376 | unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) * |
434e245d CL |
3377 | sizeof(unsigned long), GFP_KERNEL); |
3378 | ||
3379 | if (!map) | |
3380 | return -ENOMEM; | |
53e15af0 CL |
3381 | |
3382 | flush_all(s); | |
f64dc58c | 3383 | for_each_node_state(node, N_NORMAL_MEMORY) { |
53e15af0 CL |
3384 | struct kmem_cache_node *n = get_node(s, node); |
3385 | ||
434e245d | 3386 | count += validate_slab_node(s, n, map); |
53e15af0 | 3387 | } |
434e245d | 3388 | kfree(map); |
53e15af0 CL |
3389 | return count; |
3390 | } | |
3391 | ||
b3459709 CL |
3392 | #ifdef SLUB_RESILIENCY_TEST |
3393 | static void resiliency_test(void) | |
3394 | { | |
3395 | u8 *p; | |
3396 | ||
3397 | printk(KERN_ERR "SLUB resiliency testing\n"); | |
3398 | printk(KERN_ERR "-----------------------\n"); | |
3399 | printk(KERN_ERR "A. Corruption after allocation\n"); | |
3400 | ||
3401 | p = kzalloc(16, GFP_KERNEL); | |
3402 | p[16] = 0x12; | |
3403 | printk(KERN_ERR "\n1. kmalloc-16: Clobber Redzone/next pointer" | |
3404 | " 0x12->0x%p\n\n", p + 16); | |
3405 | ||
3406 | validate_slab_cache(kmalloc_caches + 4); | |
3407 | ||
3408 | /* Hmmm... The next two are dangerous */ | |
3409 | p = kzalloc(32, GFP_KERNEL); | |
3410 | p[32 + sizeof(void *)] = 0x34; | |
3411 | printk(KERN_ERR "\n2. kmalloc-32: Clobber next pointer/next slab" | |
3adbefee IM |
3412 | " 0x34 -> -0x%p\n", p); |
3413 | printk(KERN_ERR | |
3414 | "If allocated object is overwritten then not detectable\n\n"); | |
b3459709 CL |
3415 | |
3416 | validate_slab_cache(kmalloc_caches + 5); | |
3417 | p = kzalloc(64, GFP_KERNEL); | |
3418 | p += 64 + (get_cycles() & 0xff) * sizeof(void *); | |
3419 | *p = 0x56; | |
3420 | printk(KERN_ERR "\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n", | |
3421 | p); | |
3adbefee IM |
3422 | printk(KERN_ERR |
3423 | "If allocated object is overwritten then not detectable\n\n"); | |
b3459709 CL |
3424 | validate_slab_cache(kmalloc_caches + 6); |
3425 | ||
3426 | printk(KERN_ERR "\nB. Corruption after free\n"); | |
3427 | p = kzalloc(128, GFP_KERNEL); | |
3428 | kfree(p); | |
3429 | *p = 0x78; | |
3430 | printk(KERN_ERR "1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p); | |
3431 | validate_slab_cache(kmalloc_caches + 7); | |
3432 | ||
3433 | p = kzalloc(256, GFP_KERNEL); | |
3434 | kfree(p); | |
3435 | p[50] = 0x9a; | |
3adbefee IM |
3436 | printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n", |
3437 | p); | |
b3459709 CL |
3438 | validate_slab_cache(kmalloc_caches + 8); |
3439 | ||
3440 | p = kzalloc(512, GFP_KERNEL); | |
3441 | kfree(p); | |
3442 | p[512] = 0xab; | |
3443 | printk(KERN_ERR "\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p); | |
3444 | validate_slab_cache(kmalloc_caches + 9); | |
3445 | } | |
3446 | #else | |
3447 | static void resiliency_test(void) {}; | |
3448 | #endif | |
3449 | ||
88a420e4 | 3450 | /* |
672bba3a | 3451 | * Generate lists of code addresses where slabcache objects are allocated |
88a420e4 CL |
3452 | * and freed. |
3453 | */ | |
3454 | ||
3455 | struct location { | |
3456 | unsigned long count; | |
3457 | void *addr; | |
45edfa58 CL |
3458 | long long sum_time; |
3459 | long min_time; | |
3460 | long max_time; | |
3461 | long min_pid; | |
3462 | long max_pid; | |
3463 | cpumask_t cpus; | |
3464 | nodemask_t nodes; | |
88a420e4 CL |
3465 | }; |
3466 | ||
3467 | struct loc_track { | |
3468 | unsigned long max; | |
3469 | unsigned long count; | |
3470 | struct location *loc; | |
3471 | }; | |
3472 | ||
3473 | static void free_loc_track(struct loc_track *t) | |
3474 | { | |
3475 | if (t->max) | |
3476 | free_pages((unsigned long)t->loc, | |
3477 | get_order(sizeof(struct location) * t->max)); | |
3478 | } | |
3479 | ||
68dff6a9 | 3480 | static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags) |
88a420e4 CL |
3481 | { |
3482 | struct location *l; | |
3483 | int order; | |
3484 | ||
88a420e4 CL |
3485 | order = get_order(sizeof(struct location) * max); |
3486 | ||
68dff6a9 | 3487 | l = (void *)__get_free_pages(flags, order); |
88a420e4 CL |
3488 | if (!l) |
3489 | return 0; | |
3490 | ||
3491 | if (t->count) { | |
3492 | memcpy(l, t->loc, sizeof(struct location) * t->count); | |
3493 | free_loc_track(t); | |
3494 | } | |
3495 | t->max = max; | |
3496 | t->loc = l; | |
3497 | return 1; | |
3498 | } | |
3499 | ||
3500 | static int add_location(struct loc_track *t, struct kmem_cache *s, | |
45edfa58 | 3501 | const struct track *track) |
88a420e4 CL |
3502 | { |
3503 | long start, end, pos; | |
3504 | struct location *l; | |
3505 | void *caddr; | |
45edfa58 | 3506 | unsigned long age = jiffies - track->when; |
88a420e4 CL |
3507 | |
3508 | start = -1; | |
3509 | end = t->count; | |
3510 | ||
3511 | for ( ; ; ) { | |
3512 | pos = start + (end - start + 1) / 2; | |
3513 | ||
3514 | /* | |
3515 | * There is nothing at "end". If we end up there | |
3516 | * we need to add something to before end. | |
3517 | */ | |
3518 | if (pos == end) | |
3519 | break; | |
3520 | ||
3521 | caddr = t->loc[pos].addr; | |
45edfa58 CL |
3522 | if (track->addr == caddr) { |
3523 | ||
3524 | l = &t->loc[pos]; | |
3525 | l->count++; | |
3526 | if (track->when) { | |
3527 | l->sum_time += age; | |
3528 | if (age < l->min_time) | |
3529 | l->min_time = age; | |
3530 | if (age > l->max_time) | |
3531 | l->max_time = age; | |
3532 | ||
3533 | if (track->pid < l->min_pid) | |
3534 | l->min_pid = track->pid; | |
3535 | if (track->pid > l->max_pid) | |
3536 | l->max_pid = track->pid; | |
3537 | ||
3538 | cpu_set(track->cpu, l->cpus); | |
3539 | } | |
3540 | node_set(page_to_nid(virt_to_page(track)), l->nodes); | |
88a420e4 CL |
3541 | return 1; |
3542 | } | |
3543 | ||
45edfa58 | 3544 | if (track->addr < caddr) |
88a420e4 CL |
3545 | end = pos; |
3546 | else | |
3547 | start = pos; | |
3548 | } | |
3549 | ||
3550 | /* | |
672bba3a | 3551 | * Not found. Insert new tracking element. |
88a420e4 | 3552 | */ |
68dff6a9 | 3553 | if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC)) |
88a420e4 CL |
3554 | return 0; |
3555 | ||
3556 | l = t->loc + pos; | |
3557 | if (pos < t->count) | |
3558 | memmove(l + 1, l, | |
3559 | (t->count - pos) * sizeof(struct location)); | |
3560 | t->count++; | |
3561 | l->count = 1; | |
45edfa58 CL |
3562 | l->addr = track->addr; |
3563 | l->sum_time = age; | |
3564 | l->min_time = age; | |
3565 | l->max_time = age; | |
3566 | l->min_pid = track->pid; | |
3567 | l->max_pid = track->pid; | |
3568 | cpus_clear(l->cpus); | |
3569 | cpu_set(track->cpu, l->cpus); | |
3570 | nodes_clear(l->nodes); | |
3571 | node_set(page_to_nid(virt_to_page(track)), l->nodes); | |
88a420e4 CL |
3572 | return 1; |
3573 | } | |
3574 | ||
3575 | static void process_slab(struct loc_track *t, struct kmem_cache *s, | |
3576 | struct page *page, enum track_item alloc) | |
3577 | { | |
a973e9dd | 3578 | void *addr = page_address(page); |
39b26464 | 3579 | DECLARE_BITMAP(map, page->objects); |
88a420e4 CL |
3580 | void *p; |
3581 | ||
39b26464 | 3582 | bitmap_zero(map, page->objects); |
7656c72b CL |
3583 | for_each_free_object(p, s, page->freelist) |
3584 | set_bit(slab_index(p, s, addr), map); | |
88a420e4 | 3585 | |
224a88be | 3586 | for_each_object(p, s, addr, page->objects) |
45edfa58 CL |
3587 | if (!test_bit(slab_index(p, s, addr), map)) |
3588 | add_location(t, s, get_track(s, p, alloc)); | |
88a420e4 CL |
3589 | } |
3590 | ||
3591 | static int list_locations(struct kmem_cache *s, char *buf, | |
3592 | enum track_item alloc) | |
3593 | { | |
e374d483 | 3594 | int len = 0; |
88a420e4 | 3595 | unsigned long i; |
68dff6a9 | 3596 | struct loc_track t = { 0, 0, NULL }; |
88a420e4 CL |
3597 | int node; |
3598 | ||
68dff6a9 | 3599 | if (!alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location), |
ea3061d2 | 3600 | GFP_TEMPORARY)) |
68dff6a9 | 3601 | return sprintf(buf, "Out of memory\n"); |
88a420e4 CL |
3602 | |
3603 | /* Push back cpu slabs */ | |
3604 | flush_all(s); | |
3605 | ||
f64dc58c | 3606 | for_each_node_state(node, N_NORMAL_MEMORY) { |
88a420e4 CL |
3607 | struct kmem_cache_node *n = get_node(s, node); |
3608 | unsigned long flags; | |
3609 | struct page *page; | |
3610 | ||
9e86943b | 3611 | if (!atomic_long_read(&n->nr_slabs)) |
88a420e4 CL |
3612 | continue; |
3613 | ||
3614 | spin_lock_irqsave(&n->list_lock, flags); | |
3615 | list_for_each_entry(page, &n->partial, lru) | |
3616 | process_slab(&t, s, page, alloc); | |
3617 | list_for_each_entry(page, &n->full, lru) | |
3618 | process_slab(&t, s, page, alloc); | |
3619 | spin_unlock_irqrestore(&n->list_lock, flags); | |
3620 | } | |
3621 | ||
3622 | for (i = 0; i < t.count; i++) { | |
45edfa58 | 3623 | struct location *l = &t.loc[i]; |
88a420e4 | 3624 | |
e374d483 | 3625 | if (len > PAGE_SIZE - 100) |
88a420e4 | 3626 | break; |
e374d483 | 3627 | len += sprintf(buf + len, "%7ld ", l->count); |
45edfa58 CL |
3628 | |
3629 | if (l->addr) | |
e374d483 | 3630 | len += sprint_symbol(buf + len, (unsigned long)l->addr); |
88a420e4 | 3631 | else |
e374d483 | 3632 | len += sprintf(buf + len, "<not-available>"); |
45edfa58 CL |
3633 | |
3634 | if (l->sum_time != l->min_time) { | |
e374d483 | 3635 | len += sprintf(buf + len, " age=%ld/%ld/%ld", |
f8bd2258 RZ |
3636 | l->min_time, |
3637 | (long)div_u64(l->sum_time, l->count), | |
3638 | l->max_time); | |
45edfa58 | 3639 | } else |
e374d483 | 3640 | len += sprintf(buf + len, " age=%ld", |
45edfa58 CL |
3641 | l->min_time); |
3642 | ||
3643 | if (l->min_pid != l->max_pid) | |
e374d483 | 3644 | len += sprintf(buf + len, " pid=%ld-%ld", |
45edfa58 CL |
3645 | l->min_pid, l->max_pid); |
3646 | else | |
e374d483 | 3647 | len += sprintf(buf + len, " pid=%ld", |
45edfa58 CL |
3648 | l->min_pid); |
3649 | ||
84966343 | 3650 | if (num_online_cpus() > 1 && !cpus_empty(l->cpus) && |
e374d483 HH |
3651 | len < PAGE_SIZE - 60) { |
3652 | len += sprintf(buf + len, " cpus="); | |
3653 | len += cpulist_scnprintf(buf + len, PAGE_SIZE - len - 50, | |
45edfa58 CL |
3654 | l->cpus); |
3655 | } | |
3656 | ||
84966343 | 3657 | if (num_online_nodes() > 1 && !nodes_empty(l->nodes) && |
e374d483 HH |
3658 | len < PAGE_SIZE - 60) { |
3659 | len += sprintf(buf + len, " nodes="); | |
3660 | len += nodelist_scnprintf(buf + len, PAGE_SIZE - len - 50, | |
45edfa58 CL |
3661 | l->nodes); |
3662 | } | |
3663 | ||
e374d483 | 3664 | len += sprintf(buf + len, "\n"); |
88a420e4 CL |
3665 | } |
3666 | ||
3667 | free_loc_track(&t); | |
3668 | if (!t.count) | |
e374d483 HH |
3669 | len += sprintf(buf, "No data\n"); |
3670 | return len; | |
88a420e4 CL |
3671 | } |
3672 | ||
81819f0f | 3673 | enum slab_stat_type { |
205ab99d CL |
3674 | SL_ALL, /* All slabs */ |
3675 | SL_PARTIAL, /* Only partially allocated slabs */ | |
3676 | SL_CPU, /* Only slabs used for cpu caches */ | |
3677 | SL_OBJECTS, /* Determine allocated objects not slabs */ | |
3678 | SL_TOTAL /* Determine object capacity not slabs */ | |
81819f0f CL |
3679 | }; |
3680 | ||
205ab99d | 3681 | #define SO_ALL (1 << SL_ALL) |
81819f0f CL |
3682 | #define SO_PARTIAL (1 << SL_PARTIAL) |
3683 | #define SO_CPU (1 << SL_CPU) | |
3684 | #define SO_OBJECTS (1 << SL_OBJECTS) | |
205ab99d | 3685 | #define SO_TOTAL (1 << SL_TOTAL) |
81819f0f | 3686 | |
62e5c4b4 CG |
3687 | static ssize_t show_slab_objects(struct kmem_cache *s, |
3688 | char *buf, unsigned long flags) | |
81819f0f CL |
3689 | { |
3690 | unsigned long total = 0; | |
81819f0f CL |
3691 | int node; |
3692 | int x; | |
3693 | unsigned long *nodes; | |
3694 | unsigned long *per_cpu; | |
3695 | ||
3696 | nodes = kzalloc(2 * sizeof(unsigned long) * nr_node_ids, GFP_KERNEL); | |
62e5c4b4 CG |
3697 | if (!nodes) |
3698 | return -ENOMEM; | |
81819f0f CL |
3699 | per_cpu = nodes + nr_node_ids; |
3700 | ||
205ab99d CL |
3701 | if (flags & SO_CPU) { |
3702 | int cpu; | |
81819f0f | 3703 | |
205ab99d CL |
3704 | for_each_possible_cpu(cpu) { |
3705 | struct kmem_cache_cpu *c = get_cpu_slab(s, cpu); | |
dfb4f096 | 3706 | |
205ab99d CL |
3707 | if (!c || c->node < 0) |
3708 | continue; | |
3709 | ||
3710 | if (c->page) { | |
3711 | if (flags & SO_TOTAL) | |
3712 | x = c->page->objects; | |
3713 | else if (flags & SO_OBJECTS) | |
3714 | x = c->page->inuse; | |
81819f0f CL |
3715 | else |
3716 | x = 1; | |
205ab99d | 3717 | |
81819f0f | 3718 | total += x; |
205ab99d | 3719 | nodes[c->node] += x; |
81819f0f | 3720 | } |
205ab99d | 3721 | per_cpu[c->node]++; |
81819f0f CL |
3722 | } |
3723 | } | |
3724 | ||
205ab99d CL |
3725 | if (flags & SO_ALL) { |
3726 | for_each_node_state(node, N_NORMAL_MEMORY) { | |
3727 | struct kmem_cache_node *n = get_node(s, node); | |
3728 | ||
3729 | if (flags & SO_TOTAL) | |
3730 | x = atomic_long_read(&n->total_objects); | |
3731 | else if (flags & SO_OBJECTS) | |
3732 | x = atomic_long_read(&n->total_objects) - | |
3733 | count_partial(n, count_free); | |
81819f0f | 3734 | |
81819f0f | 3735 | else |
205ab99d | 3736 | x = atomic_long_read(&n->nr_slabs); |
81819f0f CL |
3737 | total += x; |
3738 | nodes[node] += x; | |
3739 | } | |
3740 | ||
205ab99d CL |
3741 | } else if (flags & SO_PARTIAL) { |
3742 | for_each_node_state(node, N_NORMAL_MEMORY) { | |
3743 | struct kmem_cache_node *n = get_node(s, node); | |
81819f0f | 3744 | |
205ab99d CL |
3745 | if (flags & SO_TOTAL) |
3746 | x = count_partial(n, count_total); | |
3747 | else if (flags & SO_OBJECTS) | |
3748 | x = count_partial(n, count_inuse); | |
81819f0f | 3749 | else |
205ab99d | 3750 | x = n->nr_partial; |
81819f0f CL |
3751 | total += x; |
3752 | nodes[node] += x; | |
3753 | } | |
3754 | } | |
81819f0f CL |
3755 | x = sprintf(buf, "%lu", total); |
3756 | #ifdef CONFIG_NUMA | |
f64dc58c | 3757 | for_each_node_state(node, N_NORMAL_MEMORY) |
81819f0f CL |
3758 | if (nodes[node]) |
3759 | x += sprintf(buf + x, " N%d=%lu", | |
3760 | node, nodes[node]); | |
3761 | #endif | |
3762 | kfree(nodes); | |
3763 | return x + sprintf(buf + x, "\n"); | |
3764 | } | |
3765 | ||
3766 | static int any_slab_objects(struct kmem_cache *s) | |
3767 | { | |
3768 | int node; | |
81819f0f | 3769 | |
dfb4f096 | 3770 | for_each_online_node(node) { |
81819f0f CL |
3771 | struct kmem_cache_node *n = get_node(s, node); |
3772 | ||
dfb4f096 CL |
3773 | if (!n) |
3774 | continue; | |
3775 | ||
4ea33e2d | 3776 | if (atomic_long_read(&n->total_objects)) |
81819f0f CL |
3777 | return 1; |
3778 | } | |
3779 | return 0; | |
3780 | } | |
3781 | ||
3782 | #define to_slab_attr(n) container_of(n, struct slab_attribute, attr) | |
3783 | #define to_slab(n) container_of(n, struct kmem_cache, kobj); | |
3784 | ||
3785 | struct slab_attribute { | |
3786 | struct attribute attr; | |
3787 | ssize_t (*show)(struct kmem_cache *s, char *buf); | |
3788 | ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count); | |
3789 | }; | |
3790 | ||
3791 | #define SLAB_ATTR_RO(_name) \ | |
3792 | static struct slab_attribute _name##_attr = __ATTR_RO(_name) | |
3793 | ||
3794 | #define SLAB_ATTR(_name) \ | |
3795 | static struct slab_attribute _name##_attr = \ | |
3796 | __ATTR(_name, 0644, _name##_show, _name##_store) | |
3797 | ||
81819f0f CL |
3798 | static ssize_t slab_size_show(struct kmem_cache *s, char *buf) |
3799 | { | |
3800 | return sprintf(buf, "%d\n", s->size); | |
3801 | } | |
3802 | SLAB_ATTR_RO(slab_size); | |
3803 | ||
3804 | static ssize_t align_show(struct kmem_cache *s, char *buf) | |
3805 | { | |
3806 | return sprintf(buf, "%d\n", s->align); | |
3807 | } | |
3808 | SLAB_ATTR_RO(align); | |
3809 | ||
3810 | static ssize_t object_size_show(struct kmem_cache *s, char *buf) | |
3811 | { | |
3812 | return sprintf(buf, "%d\n", s->objsize); | |
3813 | } | |
3814 | SLAB_ATTR_RO(object_size); | |
3815 | ||
3816 | static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf) | |
3817 | { | |
834f3d11 | 3818 | return sprintf(buf, "%d\n", oo_objects(s->oo)); |
81819f0f CL |
3819 | } |
3820 | SLAB_ATTR_RO(objs_per_slab); | |
3821 | ||
06b285dc CL |
3822 | static ssize_t order_store(struct kmem_cache *s, |
3823 | const char *buf, size_t length) | |
3824 | { | |
0121c619 CL |
3825 | unsigned long order; |
3826 | int err; | |
3827 | ||
3828 | err = strict_strtoul(buf, 10, &order); | |
3829 | if (err) | |
3830 | return err; | |
06b285dc CL |
3831 | |
3832 | if (order > slub_max_order || order < slub_min_order) | |
3833 | return -EINVAL; | |
3834 | ||
3835 | calculate_sizes(s, order); | |
3836 | return length; | |
3837 | } | |
3838 | ||
81819f0f CL |
3839 | static ssize_t order_show(struct kmem_cache *s, char *buf) |
3840 | { | |
834f3d11 | 3841 | return sprintf(buf, "%d\n", oo_order(s->oo)); |
81819f0f | 3842 | } |
06b285dc | 3843 | SLAB_ATTR(order); |
81819f0f CL |
3844 | |
3845 | static ssize_t ctor_show(struct kmem_cache *s, char *buf) | |
3846 | { | |
3847 | if (s->ctor) { | |
3848 | int n = sprint_symbol(buf, (unsigned long)s->ctor); | |
3849 | ||
3850 | return n + sprintf(buf + n, "\n"); | |
3851 | } | |
3852 | return 0; | |
3853 | } | |
3854 | SLAB_ATTR_RO(ctor); | |
3855 | ||
81819f0f CL |
3856 | static ssize_t aliases_show(struct kmem_cache *s, char *buf) |
3857 | { | |
3858 | return sprintf(buf, "%d\n", s->refcount - 1); | |
3859 | } | |
3860 | SLAB_ATTR_RO(aliases); | |
3861 | ||
3862 | static ssize_t slabs_show(struct kmem_cache *s, char *buf) | |
3863 | { | |
205ab99d | 3864 | return show_slab_objects(s, buf, SO_ALL); |
81819f0f CL |
3865 | } |
3866 | SLAB_ATTR_RO(slabs); | |
3867 | ||
3868 | static ssize_t partial_show(struct kmem_cache *s, char *buf) | |
3869 | { | |
d9acf4b7 | 3870 | return show_slab_objects(s, buf, SO_PARTIAL); |
81819f0f CL |
3871 | } |
3872 | SLAB_ATTR_RO(partial); | |
3873 | ||
3874 | static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf) | |
3875 | { | |
d9acf4b7 | 3876 | return show_slab_objects(s, buf, SO_CPU); |
81819f0f CL |
3877 | } |
3878 | SLAB_ATTR_RO(cpu_slabs); | |
3879 | ||
3880 | static ssize_t objects_show(struct kmem_cache *s, char *buf) | |
3881 | { | |
205ab99d | 3882 | return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS); |
81819f0f CL |
3883 | } |
3884 | SLAB_ATTR_RO(objects); | |
3885 | ||
205ab99d CL |
3886 | static ssize_t objects_partial_show(struct kmem_cache *s, char *buf) |
3887 | { | |
3888 | return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS); | |
3889 | } | |
3890 | SLAB_ATTR_RO(objects_partial); | |
3891 | ||
3892 | static ssize_t total_objects_show(struct kmem_cache *s, char *buf) | |
3893 | { | |
3894 | return show_slab_objects(s, buf, SO_ALL|SO_TOTAL); | |
3895 | } | |
3896 | SLAB_ATTR_RO(total_objects); | |
3897 | ||
81819f0f CL |
3898 | static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf) |
3899 | { | |
3900 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_DEBUG_FREE)); | |
3901 | } | |
3902 | ||
3903 | static ssize_t sanity_checks_store(struct kmem_cache *s, | |
3904 | const char *buf, size_t length) | |
3905 | { | |
3906 | s->flags &= ~SLAB_DEBUG_FREE; | |
3907 | if (buf[0] == '1') | |
3908 | s->flags |= SLAB_DEBUG_FREE; | |
3909 | return length; | |
3910 | } | |
3911 | SLAB_ATTR(sanity_checks); | |
3912 | ||
3913 | static ssize_t trace_show(struct kmem_cache *s, char *buf) | |
3914 | { | |
3915 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_TRACE)); | |
3916 | } | |
3917 | ||
3918 | static ssize_t trace_store(struct kmem_cache *s, const char *buf, | |
3919 | size_t length) | |
3920 | { | |
3921 | s->flags &= ~SLAB_TRACE; | |
3922 | if (buf[0] == '1') | |
3923 | s->flags |= SLAB_TRACE; | |
3924 | return length; | |
3925 | } | |
3926 | SLAB_ATTR(trace); | |
3927 | ||
3928 | static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf) | |
3929 | { | |
3930 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT)); | |
3931 | } | |
3932 | ||
3933 | static ssize_t reclaim_account_store(struct kmem_cache *s, | |
3934 | const char *buf, size_t length) | |
3935 | { | |
3936 | s->flags &= ~SLAB_RECLAIM_ACCOUNT; | |
3937 | if (buf[0] == '1') | |
3938 | s->flags |= SLAB_RECLAIM_ACCOUNT; | |
3939 | return length; | |
3940 | } | |
3941 | SLAB_ATTR(reclaim_account); | |
3942 | ||
3943 | static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf) | |
3944 | { | |
5af60839 | 3945 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN)); |
81819f0f CL |
3946 | } |
3947 | SLAB_ATTR_RO(hwcache_align); | |
3948 | ||
3949 | #ifdef CONFIG_ZONE_DMA | |
3950 | static ssize_t cache_dma_show(struct kmem_cache *s, char *buf) | |
3951 | { | |
3952 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA)); | |
3953 | } | |
3954 | SLAB_ATTR_RO(cache_dma); | |
3955 | #endif | |
3956 | ||
3957 | static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf) | |
3958 | { | |
3959 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_DESTROY_BY_RCU)); | |
3960 | } | |
3961 | SLAB_ATTR_RO(destroy_by_rcu); | |
3962 | ||
3963 | static ssize_t red_zone_show(struct kmem_cache *s, char *buf) | |
3964 | { | |
3965 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE)); | |
3966 | } | |
3967 | ||
3968 | static ssize_t red_zone_store(struct kmem_cache *s, | |
3969 | const char *buf, size_t length) | |
3970 | { | |
3971 | if (any_slab_objects(s)) | |
3972 | return -EBUSY; | |
3973 | ||
3974 | s->flags &= ~SLAB_RED_ZONE; | |
3975 | if (buf[0] == '1') | |
3976 | s->flags |= SLAB_RED_ZONE; | |
06b285dc | 3977 | calculate_sizes(s, -1); |
81819f0f CL |
3978 | return length; |
3979 | } | |
3980 | SLAB_ATTR(red_zone); | |
3981 | ||
3982 | static ssize_t poison_show(struct kmem_cache *s, char *buf) | |
3983 | { | |
3984 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_POISON)); | |
3985 | } | |
3986 | ||
3987 | static ssize_t poison_store(struct kmem_cache *s, | |
3988 | const char *buf, size_t length) | |
3989 | { | |
3990 | if (any_slab_objects(s)) | |
3991 | return -EBUSY; | |
3992 | ||
3993 | s->flags &= ~SLAB_POISON; | |
3994 | if (buf[0] == '1') | |
3995 | s->flags |= SLAB_POISON; | |
06b285dc | 3996 | calculate_sizes(s, -1); |
81819f0f CL |
3997 | return length; |
3998 | } | |
3999 | SLAB_ATTR(poison); | |
4000 | ||
4001 | static ssize_t store_user_show(struct kmem_cache *s, char *buf) | |
4002 | { | |
4003 | return sprintf(buf, "%d\n", !!(s->flags & SLAB_STORE_USER)); | |
4004 | } | |
4005 | ||
4006 | static ssize_t store_user_store(struct kmem_cache *s, | |
4007 | const char *buf, size_t length) | |
4008 | { | |
4009 | if (any_slab_objects(s)) | |
4010 | return -EBUSY; | |
4011 | ||
4012 | s->flags &= ~SLAB_STORE_USER; | |
4013 | if (buf[0] == '1') | |
4014 | s->flags |= SLAB_STORE_USER; | |
06b285dc | 4015 | calculate_sizes(s, -1); |
81819f0f CL |
4016 | return length; |
4017 | } | |
4018 | SLAB_ATTR(store_user); | |
4019 | ||
53e15af0 CL |
4020 | static ssize_t validate_show(struct kmem_cache *s, char *buf) |
4021 | { | |
4022 | return 0; | |
4023 | } | |
4024 | ||
4025 | static ssize_t validate_store(struct kmem_cache *s, | |
4026 | const char *buf, size_t length) | |
4027 | { | |
434e245d CL |
4028 | int ret = -EINVAL; |
4029 | ||
4030 | if (buf[0] == '1') { | |
4031 | ret = validate_slab_cache(s); | |
4032 | if (ret >= 0) | |
4033 | ret = length; | |
4034 | } | |
4035 | return ret; | |
53e15af0 CL |
4036 | } |
4037 | SLAB_ATTR(validate); | |
4038 | ||
2086d26a CL |
4039 | static ssize_t shrink_show(struct kmem_cache *s, char *buf) |
4040 | { | |
4041 | return 0; | |
4042 | } | |
4043 | ||
4044 | static ssize_t shrink_store(struct kmem_cache *s, | |
4045 | const char *buf, size_t length) | |
4046 | { | |
4047 | if (buf[0] == '1') { | |
4048 | int rc = kmem_cache_shrink(s); | |
4049 | ||
4050 | if (rc) | |
4051 | return rc; | |
4052 | } else | |
4053 | return -EINVAL; | |
4054 | return length; | |
4055 | } | |
4056 | SLAB_ATTR(shrink); | |
4057 | ||
88a420e4 CL |
4058 | static ssize_t alloc_calls_show(struct kmem_cache *s, char *buf) |
4059 | { | |
4060 | if (!(s->flags & SLAB_STORE_USER)) | |
4061 | return -ENOSYS; | |
4062 | return list_locations(s, buf, TRACK_ALLOC); | |
4063 | } | |
4064 | SLAB_ATTR_RO(alloc_calls); | |
4065 | ||
4066 | static ssize_t free_calls_show(struct kmem_cache *s, char *buf) | |
4067 | { | |
4068 | if (!(s->flags & SLAB_STORE_USER)) | |
4069 | return -ENOSYS; | |
4070 | return list_locations(s, buf, TRACK_FREE); | |
4071 | } | |
4072 | SLAB_ATTR_RO(free_calls); | |
4073 | ||
81819f0f | 4074 | #ifdef CONFIG_NUMA |
9824601e | 4075 | static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf) |
81819f0f | 4076 | { |
9824601e | 4077 | return sprintf(buf, "%d\n", s->remote_node_defrag_ratio / 10); |
81819f0f CL |
4078 | } |
4079 | ||
9824601e | 4080 | static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s, |
81819f0f CL |
4081 | const char *buf, size_t length) |
4082 | { | |
0121c619 CL |
4083 | unsigned long ratio; |
4084 | int err; | |
4085 | ||
4086 | err = strict_strtoul(buf, 10, &ratio); | |
4087 | if (err) | |
4088 | return err; | |
4089 | ||
4090 | if (ratio < 100) | |
4091 | s->remote_node_defrag_ratio = ratio * 10; | |
81819f0f | 4092 | |
81819f0f CL |
4093 | return length; |
4094 | } | |
9824601e | 4095 | SLAB_ATTR(remote_node_defrag_ratio); |
81819f0f CL |
4096 | #endif |
4097 | ||
8ff12cfc | 4098 | #ifdef CONFIG_SLUB_STATS |
8ff12cfc CL |
4099 | static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si) |
4100 | { | |
4101 | unsigned long sum = 0; | |
4102 | int cpu; | |
4103 | int len; | |
4104 | int *data = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL); | |
4105 | ||
4106 | if (!data) | |
4107 | return -ENOMEM; | |
4108 | ||
4109 | for_each_online_cpu(cpu) { | |
4110 | unsigned x = get_cpu_slab(s, cpu)->stat[si]; | |
4111 | ||
4112 | data[cpu] = x; | |
4113 | sum += x; | |
4114 | } | |
4115 | ||
4116 | len = sprintf(buf, "%lu", sum); | |
4117 | ||
50ef37b9 | 4118 | #ifdef CONFIG_SMP |
8ff12cfc CL |
4119 | for_each_online_cpu(cpu) { |
4120 | if (data[cpu] && len < PAGE_SIZE - 20) | |
50ef37b9 | 4121 | len += sprintf(buf + len, " C%d=%u", cpu, data[cpu]); |
8ff12cfc | 4122 | } |
50ef37b9 | 4123 | #endif |
8ff12cfc CL |
4124 | kfree(data); |
4125 | return len + sprintf(buf + len, "\n"); | |
4126 | } | |
4127 | ||
4128 | #define STAT_ATTR(si, text) \ | |
4129 | static ssize_t text##_show(struct kmem_cache *s, char *buf) \ | |
4130 | { \ | |
4131 | return show_stat(s, buf, si); \ | |
4132 | } \ | |
4133 | SLAB_ATTR_RO(text); \ | |
4134 | ||
4135 | STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath); | |
4136 | STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath); | |
4137 | STAT_ATTR(FREE_FASTPATH, free_fastpath); | |
4138 | STAT_ATTR(FREE_SLOWPATH, free_slowpath); | |
4139 | STAT_ATTR(FREE_FROZEN, free_frozen); | |
4140 | STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial); | |
4141 | STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial); | |
4142 | STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial); | |
4143 | STAT_ATTR(ALLOC_SLAB, alloc_slab); | |
4144 | STAT_ATTR(ALLOC_REFILL, alloc_refill); | |
4145 | STAT_ATTR(FREE_SLAB, free_slab); | |
4146 | STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush); | |
4147 | STAT_ATTR(DEACTIVATE_FULL, deactivate_full); | |
4148 | STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty); | |
4149 | STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head); | |
4150 | STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail); | |
4151 | STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees); | |
65c3376a | 4152 | STAT_ATTR(ORDER_FALLBACK, order_fallback); |
8ff12cfc CL |
4153 | #endif |
4154 | ||
06428780 | 4155 | static struct attribute *slab_attrs[] = { |
81819f0f CL |
4156 | &slab_size_attr.attr, |
4157 | &object_size_attr.attr, | |
4158 | &objs_per_slab_attr.attr, | |
4159 | &order_attr.attr, | |
4160 | &objects_attr.attr, | |
205ab99d CL |
4161 | &objects_partial_attr.attr, |
4162 | &total_objects_attr.attr, | |
81819f0f CL |
4163 | &slabs_attr.attr, |
4164 | &partial_attr.attr, | |
4165 | &cpu_slabs_attr.attr, | |
4166 | &ctor_attr.attr, | |
81819f0f CL |
4167 | &aliases_attr.attr, |
4168 | &align_attr.attr, | |
4169 | &sanity_checks_attr.attr, | |
4170 | &trace_attr.attr, | |
4171 | &hwcache_align_attr.attr, | |
4172 | &reclaim_account_attr.attr, | |
4173 | &destroy_by_rcu_attr.attr, | |
4174 | &red_zone_attr.attr, | |
4175 | &poison_attr.attr, | |
4176 | &store_user_attr.attr, | |
53e15af0 | 4177 | &validate_attr.attr, |
2086d26a | 4178 | &shrink_attr.attr, |
88a420e4 CL |
4179 | &alloc_calls_attr.attr, |
4180 | &free_calls_attr.attr, | |
81819f0f CL |
4181 | #ifdef CONFIG_ZONE_DMA |
4182 | &cache_dma_attr.attr, | |
4183 | #endif | |
4184 | #ifdef CONFIG_NUMA | |
9824601e | 4185 | &remote_node_defrag_ratio_attr.attr, |
8ff12cfc CL |
4186 | #endif |
4187 | #ifdef CONFIG_SLUB_STATS | |
4188 | &alloc_fastpath_attr.attr, | |
4189 | &alloc_slowpath_attr.attr, | |
4190 | &free_fastpath_attr.attr, | |
4191 | &free_slowpath_attr.attr, | |
4192 | &free_frozen_attr.attr, | |
4193 | &free_add_partial_attr.attr, | |
4194 | &free_remove_partial_attr.attr, | |
4195 | &alloc_from_partial_attr.attr, | |
4196 | &alloc_slab_attr.attr, | |
4197 | &alloc_refill_attr.attr, | |
4198 | &free_slab_attr.attr, | |
4199 | &cpuslab_flush_attr.attr, | |
4200 | &deactivate_full_attr.attr, | |
4201 | &deactivate_empty_attr.attr, | |
4202 | &deactivate_to_head_attr.attr, | |
4203 | &deactivate_to_tail_attr.attr, | |
4204 | &deactivate_remote_frees_attr.attr, | |
65c3376a | 4205 | &order_fallback_attr.attr, |
81819f0f CL |
4206 | #endif |
4207 | NULL | |
4208 | }; | |
4209 | ||
4210 | static struct attribute_group slab_attr_group = { | |
4211 | .attrs = slab_attrs, | |
4212 | }; | |
4213 | ||
4214 | static ssize_t slab_attr_show(struct kobject *kobj, | |
4215 | struct attribute *attr, | |
4216 | char *buf) | |
4217 | { | |
4218 | struct slab_attribute *attribute; | |
4219 | struct kmem_cache *s; | |
4220 | int err; | |
4221 | ||
4222 | attribute = to_slab_attr(attr); | |
4223 | s = to_slab(kobj); | |
4224 | ||
4225 | if (!attribute->show) | |
4226 | return -EIO; | |
4227 | ||
4228 | err = attribute->show(s, buf); | |
4229 | ||
4230 | return err; | |
4231 | } | |
4232 | ||
4233 | static ssize_t slab_attr_store(struct kobject *kobj, | |
4234 | struct attribute *attr, | |
4235 | const char *buf, size_t len) | |
4236 | { | |
4237 | struct slab_attribute *attribute; | |
4238 | struct kmem_cache *s; | |
4239 | int err; | |
4240 | ||
4241 | attribute = to_slab_attr(attr); | |
4242 | s = to_slab(kobj); | |
4243 | ||
4244 | if (!attribute->store) | |
4245 | return -EIO; | |
4246 | ||
4247 | err = attribute->store(s, buf, len); | |
4248 | ||
4249 | return err; | |
4250 | } | |
4251 | ||
151c602f CL |
4252 | static void kmem_cache_release(struct kobject *kobj) |
4253 | { | |
4254 | struct kmem_cache *s = to_slab(kobj); | |
4255 | ||
4256 | kfree(s); | |
4257 | } | |
4258 | ||
81819f0f CL |
4259 | static struct sysfs_ops slab_sysfs_ops = { |
4260 | .show = slab_attr_show, | |
4261 | .store = slab_attr_store, | |
4262 | }; | |
4263 | ||
4264 | static struct kobj_type slab_ktype = { | |
4265 | .sysfs_ops = &slab_sysfs_ops, | |
151c602f | 4266 | .release = kmem_cache_release |
81819f0f CL |
4267 | }; |
4268 | ||
4269 | static int uevent_filter(struct kset *kset, struct kobject *kobj) | |
4270 | { | |
4271 | struct kobj_type *ktype = get_ktype(kobj); | |
4272 | ||
4273 | if (ktype == &slab_ktype) | |
4274 | return 1; | |
4275 | return 0; | |
4276 | } | |
4277 | ||
4278 | static struct kset_uevent_ops slab_uevent_ops = { | |
4279 | .filter = uevent_filter, | |
4280 | }; | |
4281 | ||
27c3a314 | 4282 | static struct kset *slab_kset; |
81819f0f CL |
4283 | |
4284 | #define ID_STR_LENGTH 64 | |
4285 | ||
4286 | /* Create a unique string id for a slab cache: | |
6446faa2 CL |
4287 | * |
4288 | * Format :[flags-]size | |
81819f0f CL |
4289 | */ |
4290 | static char *create_unique_id(struct kmem_cache *s) | |
4291 | { | |
4292 | char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL); | |
4293 | char *p = name; | |
4294 | ||
4295 | BUG_ON(!name); | |
4296 | ||
4297 | *p++ = ':'; | |
4298 | /* | |
4299 | * First flags affecting slabcache operations. We will only | |
4300 | * get here for aliasable slabs so we do not need to support | |
4301 | * too many flags. The flags here must cover all flags that | |
4302 | * are matched during merging to guarantee that the id is | |
4303 | * unique. | |
4304 | */ | |
4305 | if (s->flags & SLAB_CACHE_DMA) | |
4306 | *p++ = 'd'; | |
4307 | if (s->flags & SLAB_RECLAIM_ACCOUNT) | |
4308 | *p++ = 'a'; | |
4309 | if (s->flags & SLAB_DEBUG_FREE) | |
4310 | *p++ = 'F'; | |
4311 | if (p != name + 1) | |
4312 | *p++ = '-'; | |
4313 | p += sprintf(p, "%07d", s->size); | |
4314 | BUG_ON(p > name + ID_STR_LENGTH - 1); | |
4315 | return name; | |
4316 | } | |
4317 | ||
4318 | static int sysfs_slab_add(struct kmem_cache *s) | |
4319 | { | |
4320 | int err; | |
4321 | const char *name; | |
4322 | int unmergeable; | |
4323 | ||
4324 | if (slab_state < SYSFS) | |
4325 | /* Defer until later */ | |
4326 | return 0; | |
4327 | ||
4328 | unmergeable = slab_unmergeable(s); | |
4329 | if (unmergeable) { | |
4330 | /* | |
4331 | * Slabcache can never be merged so we can use the name proper. | |
4332 | * This is typically the case for debug situations. In that | |
4333 | * case we can catch duplicate names easily. | |
4334 | */ | |
27c3a314 | 4335 | sysfs_remove_link(&slab_kset->kobj, s->name); |
81819f0f CL |
4336 | name = s->name; |
4337 | } else { | |
4338 | /* | |
4339 | * Create a unique name for the slab as a target | |
4340 | * for the symlinks. | |
4341 | */ | |
4342 | name = create_unique_id(s); | |
4343 | } | |
4344 | ||
27c3a314 | 4345 | s->kobj.kset = slab_kset; |
1eada11c GKH |
4346 | err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, name); |
4347 | if (err) { | |
4348 | kobject_put(&s->kobj); | |
81819f0f | 4349 | return err; |
1eada11c | 4350 | } |
81819f0f CL |
4351 | |
4352 | err = sysfs_create_group(&s->kobj, &slab_attr_group); | |
4353 | if (err) | |
4354 | return err; | |
4355 | kobject_uevent(&s->kobj, KOBJ_ADD); | |
4356 | if (!unmergeable) { | |
4357 | /* Setup first alias */ | |
4358 | sysfs_slab_alias(s, s->name); | |
4359 | kfree(name); | |
4360 | } | |
4361 | return 0; | |
4362 | } | |
4363 | ||
4364 | static void sysfs_slab_remove(struct kmem_cache *s) | |
4365 | { | |
4366 | kobject_uevent(&s->kobj, KOBJ_REMOVE); | |
4367 | kobject_del(&s->kobj); | |
151c602f | 4368 | kobject_put(&s->kobj); |
81819f0f CL |
4369 | } |
4370 | ||
4371 | /* | |
4372 | * Need to buffer aliases during bootup until sysfs becomes | |
4373 | * available lest we loose that information. | |
4374 | */ | |
4375 | struct saved_alias { | |
4376 | struct kmem_cache *s; | |
4377 | const char *name; | |
4378 | struct saved_alias *next; | |
4379 | }; | |
4380 | ||
5af328a5 | 4381 | static struct saved_alias *alias_list; |
81819f0f CL |
4382 | |
4383 | static int sysfs_slab_alias(struct kmem_cache *s, const char *name) | |
4384 | { | |
4385 | struct saved_alias *al; | |
4386 | ||
4387 | if (slab_state == SYSFS) { | |
4388 | /* | |
4389 | * If we have a leftover link then remove it. | |
4390 | */ | |
27c3a314 GKH |
4391 | sysfs_remove_link(&slab_kset->kobj, name); |
4392 | return sysfs_create_link(&slab_kset->kobj, &s->kobj, name); | |
81819f0f CL |
4393 | } |
4394 | ||
4395 | al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL); | |
4396 | if (!al) | |
4397 | return -ENOMEM; | |
4398 | ||
4399 | al->s = s; | |
4400 | al->name = name; | |
4401 | al->next = alias_list; | |
4402 | alias_list = al; | |
4403 | return 0; | |
4404 | } | |
4405 | ||
4406 | static int __init slab_sysfs_init(void) | |
4407 | { | |
5b95a4ac | 4408 | struct kmem_cache *s; |
81819f0f CL |
4409 | int err; |
4410 | ||
0ff21e46 | 4411 | slab_kset = kset_create_and_add("slab", &slab_uevent_ops, kernel_kobj); |
27c3a314 | 4412 | if (!slab_kset) { |
81819f0f CL |
4413 | printk(KERN_ERR "Cannot register slab subsystem.\n"); |
4414 | return -ENOSYS; | |
4415 | } | |
4416 | ||
26a7bd03 CL |
4417 | slab_state = SYSFS; |
4418 | ||
5b95a4ac | 4419 | list_for_each_entry(s, &slab_caches, list) { |
26a7bd03 | 4420 | err = sysfs_slab_add(s); |
5d540fb7 CL |
4421 | if (err) |
4422 | printk(KERN_ERR "SLUB: Unable to add boot slab %s" | |
4423 | " to sysfs\n", s->name); | |
26a7bd03 | 4424 | } |
81819f0f CL |
4425 | |
4426 | while (alias_list) { | |
4427 | struct saved_alias *al = alias_list; | |
4428 | ||
4429 | alias_list = alias_list->next; | |
4430 | err = sysfs_slab_alias(al->s, al->name); | |
5d540fb7 CL |
4431 | if (err) |
4432 | printk(KERN_ERR "SLUB: Unable to add boot slab alias" | |
4433 | " %s to sysfs\n", s->name); | |
81819f0f CL |
4434 | kfree(al); |
4435 | } | |
4436 | ||
4437 | resiliency_test(); | |
4438 | return 0; | |
4439 | } | |
4440 | ||
4441 | __initcall(slab_sysfs_init); | |
81819f0f | 4442 | #endif |
57ed3eda PE |
4443 | |
4444 | /* | |
4445 | * The /proc/slabinfo ABI | |
4446 | */ | |
158a9624 LT |
4447 | #ifdef CONFIG_SLABINFO |
4448 | ||
0121c619 CL |
4449 | ssize_t slabinfo_write(struct file *file, const char __user *buffer, |
4450 | size_t count, loff_t *ppos) | |
158a9624 LT |
4451 | { |
4452 | return -EINVAL; | |
4453 | } | |
4454 | ||
57ed3eda PE |
4455 | |
4456 | static void print_slabinfo_header(struct seq_file *m) | |
4457 | { | |
4458 | seq_puts(m, "slabinfo - version: 2.1\n"); | |
4459 | seq_puts(m, "# name <active_objs> <num_objs> <objsize> " | |
4460 | "<objperslab> <pagesperslab>"); | |
4461 | seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); | |
4462 | seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); | |
4463 | seq_putc(m, '\n'); | |
4464 | } | |
4465 | ||
4466 | static void *s_start(struct seq_file *m, loff_t *pos) | |
4467 | { | |
4468 | loff_t n = *pos; | |
4469 | ||
4470 | down_read(&slub_lock); | |
4471 | if (!n) | |
4472 | print_slabinfo_header(m); | |
4473 | ||
4474 | return seq_list_start(&slab_caches, *pos); | |
4475 | } | |
4476 | ||
4477 | static void *s_next(struct seq_file *m, void *p, loff_t *pos) | |
4478 | { | |
4479 | return seq_list_next(p, &slab_caches, pos); | |
4480 | } | |
4481 | ||
4482 | static void s_stop(struct seq_file *m, void *p) | |
4483 | { | |
4484 | up_read(&slub_lock); | |
4485 | } | |
4486 | ||
4487 | static int s_show(struct seq_file *m, void *p) | |
4488 | { | |
4489 | unsigned long nr_partials = 0; | |
4490 | unsigned long nr_slabs = 0; | |
4491 | unsigned long nr_inuse = 0; | |
205ab99d CL |
4492 | unsigned long nr_objs = 0; |
4493 | unsigned long nr_free = 0; | |
57ed3eda PE |
4494 | struct kmem_cache *s; |
4495 | int node; | |
4496 | ||
4497 | s = list_entry(p, struct kmem_cache, list); | |
4498 | ||
4499 | for_each_online_node(node) { | |
4500 | struct kmem_cache_node *n = get_node(s, node); | |
4501 | ||
4502 | if (!n) | |
4503 | continue; | |
4504 | ||
4505 | nr_partials += n->nr_partial; | |
4506 | nr_slabs += atomic_long_read(&n->nr_slabs); | |
205ab99d CL |
4507 | nr_objs += atomic_long_read(&n->total_objects); |
4508 | nr_free += count_partial(n, count_free); | |
57ed3eda PE |
4509 | } |
4510 | ||
205ab99d | 4511 | nr_inuse = nr_objs - nr_free; |
57ed3eda PE |
4512 | |
4513 | seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", s->name, nr_inuse, | |
834f3d11 CL |
4514 | nr_objs, s->size, oo_objects(s->oo), |
4515 | (1 << oo_order(s->oo))); | |
57ed3eda PE |
4516 | seq_printf(m, " : tunables %4u %4u %4u", 0, 0, 0); |
4517 | seq_printf(m, " : slabdata %6lu %6lu %6lu", nr_slabs, nr_slabs, | |
4518 | 0UL); | |
4519 | seq_putc(m, '\n'); | |
4520 | return 0; | |
4521 | } | |
4522 | ||
4523 | const struct seq_operations slabinfo_op = { | |
4524 | .start = s_start, | |
4525 | .next = s_next, | |
4526 | .stop = s_stop, | |
4527 | .show = s_show, | |
4528 | }; | |
4529 | ||
158a9624 | 4530 | #endif /* CONFIG_SLABINFO */ |