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1da177e4 LT |
1 | /* |
2 | * linux/mm/slab.c | |
3 | * Written by Mark Hemment, 1996/97. | |
4 | * (markhe@nextd.demon.co.uk) | |
5 | * | |
6 | * kmem_cache_destroy() + some cleanup - 1999 Andrea Arcangeli | |
7 | * | |
8 | * Major cleanup, different bufctl logic, per-cpu arrays | |
9 | * (c) 2000 Manfred Spraul | |
10 | * | |
11 | * Cleanup, make the head arrays unconditional, preparation for NUMA | |
12 | * (c) 2002 Manfred Spraul | |
13 | * | |
14 | * An implementation of the Slab Allocator as described in outline in; | |
15 | * UNIX Internals: The New Frontiers by Uresh Vahalia | |
16 | * Pub: Prentice Hall ISBN 0-13-101908-2 | |
17 | * or with a little more detail in; | |
18 | * The Slab Allocator: An Object-Caching Kernel Memory Allocator | |
19 | * Jeff Bonwick (Sun Microsystems). | |
20 | * Presented at: USENIX Summer 1994 Technical Conference | |
21 | * | |
22 | * The memory is organized in caches, one cache for each object type. | |
23 | * (e.g. inode_cache, dentry_cache, buffer_head, vm_area_struct) | |
24 | * Each cache consists out of many slabs (they are small (usually one | |
25 | * page long) and always contiguous), and each slab contains multiple | |
26 | * initialized objects. | |
27 | * | |
28 | * This means, that your constructor is used only for newly allocated | |
29 | * slabs and you must pass objects with the same intializations to | |
30 | * kmem_cache_free. | |
31 | * | |
32 | * Each cache can only support one memory type (GFP_DMA, GFP_HIGHMEM, | |
33 | * normal). If you need a special memory type, then must create a new | |
34 | * cache for that memory type. | |
35 | * | |
36 | * In order to reduce fragmentation, the slabs are sorted in 3 groups: | |
37 | * full slabs with 0 free objects | |
38 | * partial slabs | |
39 | * empty slabs with no allocated objects | |
40 | * | |
41 | * If partial slabs exist, then new allocations come from these slabs, | |
42 | * otherwise from empty slabs or new slabs are allocated. | |
43 | * | |
44 | * kmem_cache_destroy() CAN CRASH if you try to allocate from the cache | |
45 | * during kmem_cache_destroy(). The caller must prevent concurrent allocs. | |
46 | * | |
47 | * Each cache has a short per-cpu head array, most allocs | |
48 | * and frees go into that array, and if that array overflows, then 1/2 | |
49 | * of the entries in the array are given back into the global cache. | |
50 | * The head array is strictly LIFO and should improve the cache hit rates. | |
51 | * On SMP, it additionally reduces the spinlock operations. | |
52 | * | |
a737b3e2 | 53 | * The c_cpuarray may not be read with enabled local interrupts - |
1da177e4 LT |
54 | * it's changed with a smp_call_function(). |
55 | * | |
56 | * SMP synchronization: | |
57 | * constructors and destructors are called without any locking. | |
343e0d7a | 58 | * Several members in struct kmem_cache and struct slab never change, they |
1da177e4 LT |
59 | * are accessed without any locking. |
60 | * The per-cpu arrays are never accessed from the wrong cpu, no locking, | |
61 | * and local interrupts are disabled so slab code is preempt-safe. | |
62 | * The non-constant members are protected with a per-cache irq spinlock. | |
63 | * | |
64 | * Many thanks to Mark Hemment, who wrote another per-cpu slab patch | |
65 | * in 2000 - many ideas in the current implementation are derived from | |
66 | * his patch. | |
67 | * | |
68 | * Further notes from the original documentation: | |
69 | * | |
70 | * 11 April '97. Started multi-threading - markhe | |
fc0abb14 | 71 | * The global cache-chain is protected by the mutex 'cache_chain_mutex'. |
1da177e4 LT |
72 | * The sem is only needed when accessing/extending the cache-chain, which |
73 | * can never happen inside an interrupt (kmem_cache_create(), | |
74 | * kmem_cache_shrink() and kmem_cache_reap()). | |
75 | * | |
76 | * At present, each engine can be growing a cache. This should be blocked. | |
77 | * | |
e498be7d CL |
78 | * 15 March 2005. NUMA slab allocator. |
79 | * Shai Fultheim <shai@scalex86.org>. | |
80 | * Shobhit Dayal <shobhit@calsoftinc.com> | |
81 | * Alok N Kataria <alokk@calsoftinc.com> | |
82 | * Christoph Lameter <christoph@lameter.com> | |
83 | * | |
84 | * Modified the slab allocator to be node aware on NUMA systems. | |
85 | * Each node has its own list of partial, free and full slabs. | |
86 | * All object allocations for a node occur from node specific slab lists. | |
1da177e4 LT |
87 | */ |
88 | ||
89 | #include <linux/config.h> | |
90 | #include <linux/slab.h> | |
91 | #include <linux/mm.h> | |
92 | #include <linux/swap.h> | |
93 | #include <linux/cache.h> | |
94 | #include <linux/interrupt.h> | |
95 | #include <linux/init.h> | |
96 | #include <linux/compiler.h> | |
101a5001 | 97 | #include <linux/cpuset.h> |
1da177e4 LT |
98 | #include <linux/seq_file.h> |
99 | #include <linux/notifier.h> | |
100 | #include <linux/kallsyms.h> | |
101 | #include <linux/cpu.h> | |
102 | #include <linux/sysctl.h> | |
103 | #include <linux/module.h> | |
104 | #include <linux/rcupdate.h> | |
543537bd | 105 | #include <linux/string.h> |
e498be7d | 106 | #include <linux/nodemask.h> |
dc85da15 | 107 | #include <linux/mempolicy.h> |
fc0abb14 | 108 | #include <linux/mutex.h> |
1da177e4 LT |
109 | |
110 | #include <asm/uaccess.h> | |
111 | #include <asm/cacheflush.h> | |
112 | #include <asm/tlbflush.h> | |
113 | #include <asm/page.h> | |
114 | ||
115 | /* | |
116 | * DEBUG - 1 for kmem_cache_create() to honour; SLAB_DEBUG_INITIAL, | |
117 | * SLAB_RED_ZONE & SLAB_POISON. | |
118 | * 0 for faster, smaller code (especially in the critical paths). | |
119 | * | |
120 | * STATS - 1 to collect stats for /proc/slabinfo. | |
121 | * 0 for faster, smaller code (especially in the critical paths). | |
122 | * | |
123 | * FORCED_DEBUG - 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible) | |
124 | */ | |
125 | ||
126 | #ifdef CONFIG_DEBUG_SLAB | |
127 | #define DEBUG 1 | |
128 | #define STATS 1 | |
129 | #define FORCED_DEBUG 1 | |
130 | #else | |
131 | #define DEBUG 0 | |
132 | #define STATS 0 | |
133 | #define FORCED_DEBUG 0 | |
134 | #endif | |
135 | ||
1da177e4 LT |
136 | /* Shouldn't this be in a header file somewhere? */ |
137 | #define BYTES_PER_WORD sizeof(void *) | |
138 | ||
139 | #ifndef cache_line_size | |
140 | #define cache_line_size() L1_CACHE_BYTES | |
141 | #endif | |
142 | ||
143 | #ifndef ARCH_KMALLOC_MINALIGN | |
144 | /* | |
145 | * Enforce a minimum alignment for the kmalloc caches. | |
146 | * Usually, the kmalloc caches are cache_line_size() aligned, except when | |
147 | * DEBUG and FORCED_DEBUG are enabled, then they are BYTES_PER_WORD aligned. | |
148 | * Some archs want to perform DMA into kmalloc caches and need a guaranteed | |
149 | * alignment larger than BYTES_PER_WORD. ARCH_KMALLOC_MINALIGN allows that. | |
150 | * Note that this flag disables some debug features. | |
151 | */ | |
152 | #define ARCH_KMALLOC_MINALIGN 0 | |
153 | #endif | |
154 | ||
155 | #ifndef ARCH_SLAB_MINALIGN | |
156 | /* | |
157 | * Enforce a minimum alignment for all caches. | |
158 | * Intended for archs that get misalignment faults even for BYTES_PER_WORD | |
159 | * aligned buffers. Includes ARCH_KMALLOC_MINALIGN. | |
160 | * If possible: Do not enable this flag for CONFIG_DEBUG_SLAB, it disables | |
161 | * some debug features. | |
162 | */ | |
163 | #define ARCH_SLAB_MINALIGN 0 | |
164 | #endif | |
165 | ||
166 | #ifndef ARCH_KMALLOC_FLAGS | |
167 | #define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN | |
168 | #endif | |
169 | ||
170 | /* Legal flag mask for kmem_cache_create(). */ | |
171 | #if DEBUG | |
172 | # define CREATE_MASK (SLAB_DEBUG_INITIAL | SLAB_RED_ZONE | \ | |
173 | SLAB_POISON | SLAB_HWCACHE_ALIGN | \ | |
ac2b898c | 174 | SLAB_CACHE_DMA | \ |
1da177e4 LT |
175 | SLAB_MUST_HWCACHE_ALIGN | SLAB_STORE_USER | \ |
176 | SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \ | |
101a5001 | 177 | SLAB_DESTROY_BY_RCU | SLAB_MEM_SPREAD) |
1da177e4 | 178 | #else |
ac2b898c | 179 | # define CREATE_MASK (SLAB_HWCACHE_ALIGN | \ |
1da177e4 LT |
180 | SLAB_CACHE_DMA | SLAB_MUST_HWCACHE_ALIGN | \ |
181 | SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \ | |
101a5001 | 182 | SLAB_DESTROY_BY_RCU | SLAB_MEM_SPREAD) |
1da177e4 LT |
183 | #endif |
184 | ||
185 | /* | |
186 | * kmem_bufctl_t: | |
187 | * | |
188 | * Bufctl's are used for linking objs within a slab | |
189 | * linked offsets. | |
190 | * | |
191 | * This implementation relies on "struct page" for locating the cache & | |
192 | * slab an object belongs to. | |
193 | * This allows the bufctl structure to be small (one int), but limits | |
194 | * the number of objects a slab (not a cache) can contain when off-slab | |
195 | * bufctls are used. The limit is the size of the largest general cache | |
196 | * that does not use off-slab slabs. | |
197 | * For 32bit archs with 4 kB pages, is this 56. | |
198 | * This is not serious, as it is only for large objects, when it is unwise | |
199 | * to have too many per slab. | |
200 | * Note: This limit can be raised by introducing a general cache whose size | |
201 | * is less than 512 (PAGE_SIZE<<3), but greater than 256. | |
202 | */ | |
203 | ||
fa5b08d5 | 204 | typedef unsigned int kmem_bufctl_t; |
1da177e4 LT |
205 | #define BUFCTL_END (((kmem_bufctl_t)(~0U))-0) |
206 | #define BUFCTL_FREE (((kmem_bufctl_t)(~0U))-1) | |
871751e2 AV |
207 | #define BUFCTL_ACTIVE (((kmem_bufctl_t)(~0U))-2) |
208 | #define SLAB_LIMIT (((kmem_bufctl_t)(~0U))-3) | |
1da177e4 | 209 | |
1da177e4 LT |
210 | /* |
211 | * struct slab | |
212 | * | |
213 | * Manages the objs in a slab. Placed either at the beginning of mem allocated | |
214 | * for a slab, or allocated from an general cache. | |
215 | * Slabs are chained into three list: fully used, partial, fully free slabs. | |
216 | */ | |
217 | struct slab { | |
b28a02de PE |
218 | struct list_head list; |
219 | unsigned long colouroff; | |
220 | void *s_mem; /* including colour offset */ | |
221 | unsigned int inuse; /* num of objs active in slab */ | |
222 | kmem_bufctl_t free; | |
223 | unsigned short nodeid; | |
1da177e4 LT |
224 | }; |
225 | ||
226 | /* | |
227 | * struct slab_rcu | |
228 | * | |
229 | * slab_destroy on a SLAB_DESTROY_BY_RCU cache uses this structure to | |
230 | * arrange for kmem_freepages to be called via RCU. This is useful if | |
231 | * we need to approach a kernel structure obliquely, from its address | |
232 | * obtained without the usual locking. We can lock the structure to | |
233 | * stabilize it and check it's still at the given address, only if we | |
234 | * can be sure that the memory has not been meanwhile reused for some | |
235 | * other kind of object (which our subsystem's lock might corrupt). | |
236 | * | |
237 | * rcu_read_lock before reading the address, then rcu_read_unlock after | |
238 | * taking the spinlock within the structure expected at that address. | |
239 | * | |
240 | * We assume struct slab_rcu can overlay struct slab when destroying. | |
241 | */ | |
242 | struct slab_rcu { | |
b28a02de | 243 | struct rcu_head head; |
343e0d7a | 244 | struct kmem_cache *cachep; |
b28a02de | 245 | void *addr; |
1da177e4 LT |
246 | }; |
247 | ||
248 | /* | |
249 | * struct array_cache | |
250 | * | |
1da177e4 LT |
251 | * Purpose: |
252 | * - LIFO ordering, to hand out cache-warm objects from _alloc | |
253 | * - reduce the number of linked list operations | |
254 | * - reduce spinlock operations | |
255 | * | |
256 | * The limit is stored in the per-cpu structure to reduce the data cache | |
257 | * footprint. | |
258 | * | |
259 | */ | |
260 | struct array_cache { | |
261 | unsigned int avail; | |
262 | unsigned int limit; | |
263 | unsigned int batchcount; | |
264 | unsigned int touched; | |
e498be7d | 265 | spinlock_t lock; |
a737b3e2 AM |
266 | void *entry[0]; /* |
267 | * Must have this definition in here for the proper | |
268 | * alignment of array_cache. Also simplifies accessing | |
269 | * the entries. | |
270 | * [0] is for gcc 2.95. It should really be []. | |
271 | */ | |
1da177e4 LT |
272 | }; |
273 | ||
a737b3e2 AM |
274 | /* |
275 | * bootstrap: The caches do not work without cpuarrays anymore, but the | |
276 | * cpuarrays are allocated from the generic caches... | |
1da177e4 LT |
277 | */ |
278 | #define BOOT_CPUCACHE_ENTRIES 1 | |
279 | struct arraycache_init { | |
280 | struct array_cache cache; | |
b28a02de | 281 | void *entries[BOOT_CPUCACHE_ENTRIES]; |
1da177e4 LT |
282 | }; |
283 | ||
284 | /* | |
e498be7d | 285 | * The slab lists for all objects. |
1da177e4 LT |
286 | */ |
287 | struct kmem_list3 { | |
b28a02de PE |
288 | struct list_head slabs_partial; /* partial list first, better asm code */ |
289 | struct list_head slabs_full; | |
290 | struct list_head slabs_free; | |
291 | unsigned long free_objects; | |
b28a02de | 292 | unsigned int free_limit; |
2e1217cf | 293 | unsigned int colour_next; /* Per-node cache coloring */ |
b28a02de PE |
294 | spinlock_t list_lock; |
295 | struct array_cache *shared; /* shared per node */ | |
296 | struct array_cache **alien; /* on other nodes */ | |
35386e3b CL |
297 | unsigned long next_reap; /* updated without locking */ |
298 | int free_touched; /* updated without locking */ | |
1da177e4 LT |
299 | }; |
300 | ||
e498be7d CL |
301 | /* |
302 | * Need this for bootstrapping a per node allocator. | |
303 | */ | |
304 | #define NUM_INIT_LISTS (2 * MAX_NUMNODES + 1) | |
305 | struct kmem_list3 __initdata initkmem_list3[NUM_INIT_LISTS]; | |
306 | #define CACHE_CACHE 0 | |
307 | #define SIZE_AC 1 | |
308 | #define SIZE_L3 (1 + MAX_NUMNODES) | |
309 | ||
310 | /* | |
a737b3e2 AM |
311 | * This function must be completely optimized away if a constant is passed to |
312 | * it. Mostly the same as what is in linux/slab.h except it returns an index. | |
e498be7d | 313 | */ |
7243cc05 | 314 | static __always_inline int index_of(const size_t size) |
e498be7d | 315 | { |
5ec8a847 SR |
316 | extern void __bad_size(void); |
317 | ||
e498be7d CL |
318 | if (__builtin_constant_p(size)) { |
319 | int i = 0; | |
320 | ||
321 | #define CACHE(x) \ | |
322 | if (size <=x) \ | |
323 | return i; \ | |
324 | else \ | |
325 | i++; | |
326 | #include "linux/kmalloc_sizes.h" | |
327 | #undef CACHE | |
5ec8a847 | 328 | __bad_size(); |
7243cc05 | 329 | } else |
5ec8a847 | 330 | __bad_size(); |
e498be7d CL |
331 | return 0; |
332 | } | |
333 | ||
334 | #define INDEX_AC index_of(sizeof(struct arraycache_init)) | |
335 | #define INDEX_L3 index_of(sizeof(struct kmem_list3)) | |
1da177e4 | 336 | |
5295a74c | 337 | static void kmem_list3_init(struct kmem_list3 *parent) |
e498be7d CL |
338 | { |
339 | INIT_LIST_HEAD(&parent->slabs_full); | |
340 | INIT_LIST_HEAD(&parent->slabs_partial); | |
341 | INIT_LIST_HEAD(&parent->slabs_free); | |
342 | parent->shared = NULL; | |
343 | parent->alien = NULL; | |
2e1217cf | 344 | parent->colour_next = 0; |
e498be7d CL |
345 | spin_lock_init(&parent->list_lock); |
346 | parent->free_objects = 0; | |
347 | parent->free_touched = 0; | |
348 | } | |
349 | ||
a737b3e2 AM |
350 | #define MAKE_LIST(cachep, listp, slab, nodeid) \ |
351 | do { \ | |
352 | INIT_LIST_HEAD(listp); \ | |
353 | list_splice(&(cachep->nodelists[nodeid]->slab), listp); \ | |
e498be7d CL |
354 | } while (0) |
355 | ||
a737b3e2 AM |
356 | #define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ |
357 | do { \ | |
e498be7d CL |
358 | MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \ |
359 | MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \ | |
360 | MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \ | |
361 | } while (0) | |
1da177e4 LT |
362 | |
363 | /* | |
343e0d7a | 364 | * struct kmem_cache |
1da177e4 LT |
365 | * |
366 | * manages a cache. | |
367 | */ | |
b28a02de | 368 | |
2109a2d1 | 369 | struct kmem_cache { |
1da177e4 | 370 | /* 1) per-cpu data, touched during every alloc/free */ |
b28a02de | 371 | struct array_cache *array[NR_CPUS]; |
b5d8ca7c | 372 | /* 2) Cache tunables. Protected by cache_chain_mutex */ |
b28a02de PE |
373 | unsigned int batchcount; |
374 | unsigned int limit; | |
375 | unsigned int shared; | |
b5d8ca7c | 376 | |
3dafccf2 | 377 | unsigned int buffer_size; |
b5d8ca7c | 378 | /* 3) touched by every alloc & free from the backend */ |
b28a02de | 379 | struct kmem_list3 *nodelists[MAX_NUMNODES]; |
b5d8ca7c | 380 | |
a737b3e2 AM |
381 | unsigned int flags; /* constant flags */ |
382 | unsigned int num; /* # of objs per slab */ | |
1da177e4 | 383 | |
b5d8ca7c | 384 | /* 4) cache_grow/shrink */ |
1da177e4 | 385 | /* order of pgs per slab (2^n) */ |
b28a02de | 386 | unsigned int gfporder; |
1da177e4 LT |
387 | |
388 | /* force GFP flags, e.g. GFP_DMA */ | |
b28a02de | 389 | gfp_t gfpflags; |
1da177e4 | 390 | |
a737b3e2 | 391 | size_t colour; /* cache colouring range */ |
b28a02de | 392 | unsigned int colour_off; /* colour offset */ |
343e0d7a | 393 | struct kmem_cache *slabp_cache; |
b28a02de | 394 | unsigned int slab_size; |
a737b3e2 | 395 | unsigned int dflags; /* dynamic flags */ |
1da177e4 LT |
396 | |
397 | /* constructor func */ | |
343e0d7a | 398 | void (*ctor) (void *, struct kmem_cache *, unsigned long); |
1da177e4 LT |
399 | |
400 | /* de-constructor func */ | |
343e0d7a | 401 | void (*dtor) (void *, struct kmem_cache *, unsigned long); |
1da177e4 | 402 | |
b5d8ca7c | 403 | /* 5) cache creation/removal */ |
b28a02de PE |
404 | const char *name; |
405 | struct list_head next; | |
1da177e4 | 406 | |
b5d8ca7c | 407 | /* 6) statistics */ |
1da177e4 | 408 | #if STATS |
b28a02de PE |
409 | unsigned long num_active; |
410 | unsigned long num_allocations; | |
411 | unsigned long high_mark; | |
412 | unsigned long grown; | |
413 | unsigned long reaped; | |
414 | unsigned long errors; | |
415 | unsigned long max_freeable; | |
416 | unsigned long node_allocs; | |
417 | unsigned long node_frees; | |
fb7faf33 | 418 | unsigned long node_overflow; |
b28a02de PE |
419 | atomic_t allochit; |
420 | atomic_t allocmiss; | |
421 | atomic_t freehit; | |
422 | atomic_t freemiss; | |
1da177e4 LT |
423 | #endif |
424 | #if DEBUG | |
3dafccf2 MS |
425 | /* |
426 | * If debugging is enabled, then the allocator can add additional | |
427 | * fields and/or padding to every object. buffer_size contains the total | |
428 | * object size including these internal fields, the following two | |
429 | * variables contain the offset to the user object and its size. | |
430 | */ | |
431 | int obj_offset; | |
432 | int obj_size; | |
1da177e4 LT |
433 | #endif |
434 | }; | |
435 | ||
436 | #define CFLGS_OFF_SLAB (0x80000000UL) | |
437 | #define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) | |
438 | ||
439 | #define BATCHREFILL_LIMIT 16 | |
a737b3e2 AM |
440 | /* |
441 | * Optimization question: fewer reaps means less probability for unnessary | |
442 | * cpucache drain/refill cycles. | |
1da177e4 | 443 | * |
dc6f3f27 | 444 | * OTOH the cpuarrays can contain lots of objects, |
1da177e4 LT |
445 | * which could lock up otherwise freeable slabs. |
446 | */ | |
447 | #define REAPTIMEOUT_CPUC (2*HZ) | |
448 | #define REAPTIMEOUT_LIST3 (4*HZ) | |
449 | ||
450 | #if STATS | |
451 | #define STATS_INC_ACTIVE(x) ((x)->num_active++) | |
452 | #define STATS_DEC_ACTIVE(x) ((x)->num_active--) | |
453 | #define STATS_INC_ALLOCED(x) ((x)->num_allocations++) | |
454 | #define STATS_INC_GROWN(x) ((x)->grown++) | |
455 | #define STATS_INC_REAPED(x) ((x)->reaped++) | |
a737b3e2 AM |
456 | #define STATS_SET_HIGH(x) \ |
457 | do { \ | |
458 | if ((x)->num_active > (x)->high_mark) \ | |
459 | (x)->high_mark = (x)->num_active; \ | |
460 | } while (0) | |
1da177e4 LT |
461 | #define STATS_INC_ERR(x) ((x)->errors++) |
462 | #define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) | |
e498be7d | 463 | #define STATS_INC_NODEFREES(x) ((x)->node_frees++) |
fb7faf33 | 464 | #define STATS_INC_ACOVERFLOW(x) ((x)->node_overflow++) |
a737b3e2 AM |
465 | #define STATS_SET_FREEABLE(x, i) \ |
466 | do { \ | |
467 | if ((x)->max_freeable < i) \ | |
468 | (x)->max_freeable = i; \ | |
469 | } while (0) | |
1da177e4 LT |
470 | #define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) |
471 | #define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) | |
472 | #define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) | |
473 | #define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) | |
474 | #else | |
475 | #define STATS_INC_ACTIVE(x) do { } while (0) | |
476 | #define STATS_DEC_ACTIVE(x) do { } while (0) | |
477 | #define STATS_INC_ALLOCED(x) do { } while (0) | |
478 | #define STATS_INC_GROWN(x) do { } while (0) | |
479 | #define STATS_INC_REAPED(x) do { } while (0) | |
480 | #define STATS_SET_HIGH(x) do { } while (0) | |
481 | #define STATS_INC_ERR(x) do { } while (0) | |
482 | #define STATS_INC_NODEALLOCS(x) do { } while (0) | |
e498be7d | 483 | #define STATS_INC_NODEFREES(x) do { } while (0) |
fb7faf33 | 484 | #define STATS_INC_ACOVERFLOW(x) do { } while (0) |
a737b3e2 | 485 | #define STATS_SET_FREEABLE(x, i) do { } while (0) |
1da177e4 LT |
486 | #define STATS_INC_ALLOCHIT(x) do { } while (0) |
487 | #define STATS_INC_ALLOCMISS(x) do { } while (0) | |
488 | #define STATS_INC_FREEHIT(x) do { } while (0) | |
489 | #define STATS_INC_FREEMISS(x) do { } while (0) | |
490 | #endif | |
491 | ||
492 | #if DEBUG | |
a737b3e2 AM |
493 | /* |
494 | * Magic nums for obj red zoning. | |
1da177e4 LT |
495 | * Placed in the first word before and the first word after an obj. |
496 | */ | |
497 | #define RED_INACTIVE 0x5A2CF071UL /* when obj is inactive */ | |
498 | #define RED_ACTIVE 0x170FC2A5UL /* when obj is active */ | |
499 | ||
500 | /* ...and for poisoning */ | |
501 | #define POISON_INUSE 0x5a /* for use-uninitialised poisoning */ | |
502 | #define POISON_FREE 0x6b /* for use-after-free poisoning */ | |
503 | #define POISON_END 0xa5 /* end-byte of poisoning */ | |
504 | ||
a737b3e2 AM |
505 | /* |
506 | * memory layout of objects: | |
1da177e4 | 507 | * 0 : objp |
3dafccf2 | 508 | * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that |
1da177e4 LT |
509 | * the end of an object is aligned with the end of the real |
510 | * allocation. Catches writes behind the end of the allocation. | |
3dafccf2 | 511 | * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1: |
1da177e4 | 512 | * redzone word. |
3dafccf2 MS |
513 | * cachep->obj_offset: The real object. |
514 | * cachep->buffer_size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long] | |
a737b3e2 AM |
515 | * cachep->buffer_size - 1* BYTES_PER_WORD: last caller address |
516 | * [BYTES_PER_WORD long] | |
1da177e4 | 517 | */ |
343e0d7a | 518 | static int obj_offset(struct kmem_cache *cachep) |
1da177e4 | 519 | { |
3dafccf2 | 520 | return cachep->obj_offset; |
1da177e4 LT |
521 | } |
522 | ||
343e0d7a | 523 | static int obj_size(struct kmem_cache *cachep) |
1da177e4 | 524 | { |
3dafccf2 | 525 | return cachep->obj_size; |
1da177e4 LT |
526 | } |
527 | ||
343e0d7a | 528 | static unsigned long *dbg_redzone1(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
529 | { |
530 | BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); | |
3dafccf2 | 531 | return (unsigned long*) (objp+obj_offset(cachep)-BYTES_PER_WORD); |
1da177e4 LT |
532 | } |
533 | ||
343e0d7a | 534 | static unsigned long *dbg_redzone2(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
535 | { |
536 | BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); | |
537 | if (cachep->flags & SLAB_STORE_USER) | |
3dafccf2 | 538 | return (unsigned long *)(objp + cachep->buffer_size - |
b28a02de | 539 | 2 * BYTES_PER_WORD); |
3dafccf2 | 540 | return (unsigned long *)(objp + cachep->buffer_size - BYTES_PER_WORD); |
1da177e4 LT |
541 | } |
542 | ||
343e0d7a | 543 | static void **dbg_userword(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
544 | { |
545 | BUG_ON(!(cachep->flags & SLAB_STORE_USER)); | |
3dafccf2 | 546 | return (void **)(objp + cachep->buffer_size - BYTES_PER_WORD); |
1da177e4 LT |
547 | } |
548 | ||
549 | #else | |
550 | ||
3dafccf2 MS |
551 | #define obj_offset(x) 0 |
552 | #define obj_size(cachep) (cachep->buffer_size) | |
1da177e4 LT |
553 | #define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long *)NULL;}) |
554 | #define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long *)NULL;}) | |
555 | #define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;}) | |
556 | ||
557 | #endif | |
558 | ||
559 | /* | |
a737b3e2 AM |
560 | * Maximum size of an obj (in 2^order pages) and absolute limit for the gfp |
561 | * order. | |
1da177e4 LT |
562 | */ |
563 | #if defined(CONFIG_LARGE_ALLOCS) | |
564 | #define MAX_OBJ_ORDER 13 /* up to 32Mb */ | |
565 | #define MAX_GFP_ORDER 13 /* up to 32Mb */ | |
566 | #elif defined(CONFIG_MMU) | |
567 | #define MAX_OBJ_ORDER 5 /* 32 pages */ | |
568 | #define MAX_GFP_ORDER 5 /* 32 pages */ | |
569 | #else | |
570 | #define MAX_OBJ_ORDER 8 /* up to 1Mb */ | |
571 | #define MAX_GFP_ORDER 8 /* up to 1Mb */ | |
572 | #endif | |
573 | ||
574 | /* | |
575 | * Do not go above this order unless 0 objects fit into the slab. | |
576 | */ | |
577 | #define BREAK_GFP_ORDER_HI 1 | |
578 | #define BREAK_GFP_ORDER_LO 0 | |
579 | static int slab_break_gfp_order = BREAK_GFP_ORDER_LO; | |
580 | ||
a737b3e2 AM |
581 | /* |
582 | * Functions for storing/retrieving the cachep and or slab from the page | |
583 | * allocator. These are used to find the slab an obj belongs to. With kfree(), | |
584 | * these are used to find the cache which an obj belongs to. | |
1da177e4 | 585 | */ |
065d41cb PE |
586 | static inline void page_set_cache(struct page *page, struct kmem_cache *cache) |
587 | { | |
588 | page->lru.next = (struct list_head *)cache; | |
589 | } | |
590 | ||
591 | static inline struct kmem_cache *page_get_cache(struct page *page) | |
592 | { | |
84097518 NP |
593 | if (unlikely(PageCompound(page))) |
594 | page = (struct page *)page_private(page); | |
065d41cb PE |
595 | return (struct kmem_cache *)page->lru.next; |
596 | } | |
597 | ||
598 | static inline void page_set_slab(struct page *page, struct slab *slab) | |
599 | { | |
600 | page->lru.prev = (struct list_head *)slab; | |
601 | } | |
602 | ||
603 | static inline struct slab *page_get_slab(struct page *page) | |
604 | { | |
84097518 NP |
605 | if (unlikely(PageCompound(page))) |
606 | page = (struct page *)page_private(page); | |
065d41cb PE |
607 | return (struct slab *)page->lru.prev; |
608 | } | |
1da177e4 | 609 | |
6ed5eb22 PE |
610 | static inline struct kmem_cache *virt_to_cache(const void *obj) |
611 | { | |
612 | struct page *page = virt_to_page(obj); | |
613 | return page_get_cache(page); | |
614 | } | |
615 | ||
616 | static inline struct slab *virt_to_slab(const void *obj) | |
617 | { | |
618 | struct page *page = virt_to_page(obj); | |
619 | return page_get_slab(page); | |
620 | } | |
621 | ||
8fea4e96 PE |
622 | static inline void *index_to_obj(struct kmem_cache *cache, struct slab *slab, |
623 | unsigned int idx) | |
624 | { | |
625 | return slab->s_mem + cache->buffer_size * idx; | |
626 | } | |
627 | ||
628 | static inline unsigned int obj_to_index(struct kmem_cache *cache, | |
629 | struct slab *slab, void *obj) | |
630 | { | |
631 | return (unsigned)(obj - slab->s_mem) / cache->buffer_size; | |
632 | } | |
633 | ||
a737b3e2 AM |
634 | /* |
635 | * These are the default caches for kmalloc. Custom caches can have other sizes. | |
636 | */ | |
1da177e4 LT |
637 | struct cache_sizes malloc_sizes[] = { |
638 | #define CACHE(x) { .cs_size = (x) }, | |
639 | #include <linux/kmalloc_sizes.h> | |
640 | CACHE(ULONG_MAX) | |
641 | #undef CACHE | |
642 | }; | |
643 | EXPORT_SYMBOL(malloc_sizes); | |
644 | ||
645 | /* Must match cache_sizes above. Out of line to keep cache footprint low. */ | |
646 | struct cache_names { | |
647 | char *name; | |
648 | char *name_dma; | |
649 | }; | |
650 | ||
651 | static struct cache_names __initdata cache_names[] = { | |
652 | #define CACHE(x) { .name = "size-" #x, .name_dma = "size-" #x "(DMA)" }, | |
653 | #include <linux/kmalloc_sizes.h> | |
b28a02de | 654 | {NULL,} |
1da177e4 LT |
655 | #undef CACHE |
656 | }; | |
657 | ||
658 | static struct arraycache_init initarray_cache __initdata = | |
b28a02de | 659 | { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; |
1da177e4 | 660 | static struct arraycache_init initarray_generic = |
b28a02de | 661 | { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; |
1da177e4 LT |
662 | |
663 | /* internal cache of cache description objs */ | |
343e0d7a | 664 | static struct kmem_cache cache_cache = { |
b28a02de PE |
665 | .batchcount = 1, |
666 | .limit = BOOT_CPUCACHE_ENTRIES, | |
667 | .shared = 1, | |
343e0d7a | 668 | .buffer_size = sizeof(struct kmem_cache), |
b28a02de | 669 | .name = "kmem_cache", |
1da177e4 | 670 | #if DEBUG |
343e0d7a | 671 | .obj_size = sizeof(struct kmem_cache), |
1da177e4 LT |
672 | #endif |
673 | }; | |
674 | ||
675 | /* Guard access to the cache-chain. */ | |
fc0abb14 | 676 | static DEFINE_MUTEX(cache_chain_mutex); |
1da177e4 LT |
677 | static struct list_head cache_chain; |
678 | ||
679 | /* | |
a737b3e2 AM |
680 | * vm_enough_memory() looks at this to determine how many slab-allocated pages |
681 | * are possibly freeable under pressure | |
1da177e4 LT |
682 | * |
683 | * SLAB_RECLAIM_ACCOUNT turns this on per-slab | |
684 | */ | |
685 | atomic_t slab_reclaim_pages; | |
1da177e4 LT |
686 | |
687 | /* | |
688 | * chicken and egg problem: delay the per-cpu array allocation | |
689 | * until the general caches are up. | |
690 | */ | |
691 | static enum { | |
692 | NONE, | |
e498be7d CL |
693 | PARTIAL_AC, |
694 | PARTIAL_L3, | |
1da177e4 LT |
695 | FULL |
696 | } g_cpucache_up; | |
697 | ||
39d24e64 MK |
698 | /* |
699 | * used by boot code to determine if it can use slab based allocator | |
700 | */ | |
701 | int slab_is_available(void) | |
702 | { | |
703 | return g_cpucache_up == FULL; | |
704 | } | |
705 | ||
1da177e4 LT |
706 | static DEFINE_PER_CPU(struct work_struct, reap_work); |
707 | ||
a737b3e2 AM |
708 | static void free_block(struct kmem_cache *cachep, void **objpp, int len, |
709 | int node); | |
343e0d7a | 710 | static void enable_cpucache(struct kmem_cache *cachep); |
b28a02de | 711 | static void cache_reap(void *unused); |
343e0d7a | 712 | static int __node_shrink(struct kmem_cache *cachep, int node); |
1da177e4 | 713 | |
343e0d7a | 714 | static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) |
1da177e4 LT |
715 | { |
716 | return cachep->array[smp_processor_id()]; | |
717 | } | |
718 | ||
a737b3e2 AM |
719 | static inline struct kmem_cache *__find_general_cachep(size_t size, |
720 | gfp_t gfpflags) | |
1da177e4 LT |
721 | { |
722 | struct cache_sizes *csizep = malloc_sizes; | |
723 | ||
724 | #if DEBUG | |
725 | /* This happens if someone tries to call | |
b28a02de PE |
726 | * kmem_cache_create(), or __kmalloc(), before |
727 | * the generic caches are initialized. | |
728 | */ | |
c7e43c78 | 729 | BUG_ON(malloc_sizes[INDEX_AC].cs_cachep == NULL); |
1da177e4 LT |
730 | #endif |
731 | while (size > csizep->cs_size) | |
732 | csizep++; | |
733 | ||
734 | /* | |
0abf40c1 | 735 | * Really subtle: The last entry with cs->cs_size==ULONG_MAX |
1da177e4 LT |
736 | * has cs_{dma,}cachep==NULL. Thus no special case |
737 | * for large kmalloc calls required. | |
738 | */ | |
739 | if (unlikely(gfpflags & GFP_DMA)) | |
740 | return csizep->cs_dmacachep; | |
741 | return csizep->cs_cachep; | |
742 | } | |
743 | ||
343e0d7a | 744 | struct kmem_cache *kmem_find_general_cachep(size_t size, gfp_t gfpflags) |
97e2bde4 MS |
745 | { |
746 | return __find_general_cachep(size, gfpflags); | |
747 | } | |
748 | EXPORT_SYMBOL(kmem_find_general_cachep); | |
749 | ||
fbaccacf | 750 | static size_t slab_mgmt_size(size_t nr_objs, size_t align) |
1da177e4 | 751 | { |
fbaccacf SR |
752 | return ALIGN(sizeof(struct slab)+nr_objs*sizeof(kmem_bufctl_t), align); |
753 | } | |
1da177e4 | 754 | |
a737b3e2 AM |
755 | /* |
756 | * Calculate the number of objects and left-over bytes for a given buffer size. | |
757 | */ | |
fbaccacf SR |
758 | static void cache_estimate(unsigned long gfporder, size_t buffer_size, |
759 | size_t align, int flags, size_t *left_over, | |
760 | unsigned int *num) | |
761 | { | |
762 | int nr_objs; | |
763 | size_t mgmt_size; | |
764 | size_t slab_size = PAGE_SIZE << gfporder; | |
1da177e4 | 765 | |
fbaccacf SR |
766 | /* |
767 | * The slab management structure can be either off the slab or | |
768 | * on it. For the latter case, the memory allocated for a | |
769 | * slab is used for: | |
770 | * | |
771 | * - The struct slab | |
772 | * - One kmem_bufctl_t for each object | |
773 | * - Padding to respect alignment of @align | |
774 | * - @buffer_size bytes for each object | |
775 | * | |
776 | * If the slab management structure is off the slab, then the | |
777 | * alignment will already be calculated into the size. Because | |
778 | * the slabs are all pages aligned, the objects will be at the | |
779 | * correct alignment when allocated. | |
780 | */ | |
781 | if (flags & CFLGS_OFF_SLAB) { | |
782 | mgmt_size = 0; | |
783 | nr_objs = slab_size / buffer_size; | |
784 | ||
785 | if (nr_objs > SLAB_LIMIT) | |
786 | nr_objs = SLAB_LIMIT; | |
787 | } else { | |
788 | /* | |
789 | * Ignore padding for the initial guess. The padding | |
790 | * is at most @align-1 bytes, and @buffer_size is at | |
791 | * least @align. In the worst case, this result will | |
792 | * be one greater than the number of objects that fit | |
793 | * into the memory allocation when taking the padding | |
794 | * into account. | |
795 | */ | |
796 | nr_objs = (slab_size - sizeof(struct slab)) / | |
797 | (buffer_size + sizeof(kmem_bufctl_t)); | |
798 | ||
799 | /* | |
800 | * This calculated number will be either the right | |
801 | * amount, or one greater than what we want. | |
802 | */ | |
803 | if (slab_mgmt_size(nr_objs, align) + nr_objs*buffer_size | |
804 | > slab_size) | |
805 | nr_objs--; | |
806 | ||
807 | if (nr_objs > SLAB_LIMIT) | |
808 | nr_objs = SLAB_LIMIT; | |
809 | ||
810 | mgmt_size = slab_mgmt_size(nr_objs, align); | |
811 | } | |
812 | *num = nr_objs; | |
813 | *left_over = slab_size - nr_objs*buffer_size - mgmt_size; | |
1da177e4 LT |
814 | } |
815 | ||
816 | #define slab_error(cachep, msg) __slab_error(__FUNCTION__, cachep, msg) | |
817 | ||
a737b3e2 AM |
818 | static void __slab_error(const char *function, struct kmem_cache *cachep, |
819 | char *msg) | |
1da177e4 LT |
820 | { |
821 | printk(KERN_ERR "slab error in %s(): cache `%s': %s\n", | |
b28a02de | 822 | function, cachep->name, msg); |
1da177e4 LT |
823 | dump_stack(); |
824 | } | |
825 | ||
8fce4d8e CL |
826 | #ifdef CONFIG_NUMA |
827 | /* | |
828 | * Special reaping functions for NUMA systems called from cache_reap(). | |
829 | * These take care of doing round robin flushing of alien caches (containing | |
830 | * objects freed on different nodes from which they were allocated) and the | |
831 | * flushing of remote pcps by calling drain_node_pages. | |
832 | */ | |
833 | static DEFINE_PER_CPU(unsigned long, reap_node); | |
834 | ||
835 | static void init_reap_node(int cpu) | |
836 | { | |
837 | int node; | |
838 | ||
839 | node = next_node(cpu_to_node(cpu), node_online_map); | |
840 | if (node == MAX_NUMNODES) | |
442295c9 | 841 | node = first_node(node_online_map); |
8fce4d8e CL |
842 | |
843 | __get_cpu_var(reap_node) = node; | |
844 | } | |
845 | ||
846 | static void next_reap_node(void) | |
847 | { | |
848 | int node = __get_cpu_var(reap_node); | |
849 | ||
850 | /* | |
851 | * Also drain per cpu pages on remote zones | |
852 | */ | |
853 | if (node != numa_node_id()) | |
854 | drain_node_pages(node); | |
855 | ||
856 | node = next_node(node, node_online_map); | |
857 | if (unlikely(node >= MAX_NUMNODES)) | |
858 | node = first_node(node_online_map); | |
859 | __get_cpu_var(reap_node) = node; | |
860 | } | |
861 | ||
862 | #else | |
863 | #define init_reap_node(cpu) do { } while (0) | |
864 | #define next_reap_node(void) do { } while (0) | |
865 | #endif | |
866 | ||
1da177e4 LT |
867 | /* |
868 | * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz | |
869 | * via the workqueue/eventd. | |
870 | * Add the CPU number into the expiration time to minimize the possibility of | |
871 | * the CPUs getting into lockstep and contending for the global cache chain | |
872 | * lock. | |
873 | */ | |
874 | static void __devinit start_cpu_timer(int cpu) | |
875 | { | |
876 | struct work_struct *reap_work = &per_cpu(reap_work, cpu); | |
877 | ||
878 | /* | |
879 | * When this gets called from do_initcalls via cpucache_init(), | |
880 | * init_workqueues() has already run, so keventd will be setup | |
881 | * at that time. | |
882 | */ | |
883 | if (keventd_up() && reap_work->func == NULL) { | |
8fce4d8e | 884 | init_reap_node(cpu); |
1da177e4 LT |
885 | INIT_WORK(reap_work, cache_reap, NULL); |
886 | schedule_delayed_work_on(cpu, reap_work, HZ + 3 * cpu); | |
887 | } | |
888 | } | |
889 | ||
e498be7d | 890 | static struct array_cache *alloc_arraycache(int node, int entries, |
b28a02de | 891 | int batchcount) |
1da177e4 | 892 | { |
b28a02de | 893 | int memsize = sizeof(void *) * entries + sizeof(struct array_cache); |
1da177e4 LT |
894 | struct array_cache *nc = NULL; |
895 | ||
e498be7d | 896 | nc = kmalloc_node(memsize, GFP_KERNEL, node); |
1da177e4 LT |
897 | if (nc) { |
898 | nc->avail = 0; | |
899 | nc->limit = entries; | |
900 | nc->batchcount = batchcount; | |
901 | nc->touched = 0; | |
e498be7d | 902 | spin_lock_init(&nc->lock); |
1da177e4 LT |
903 | } |
904 | return nc; | |
905 | } | |
906 | ||
3ded175a CL |
907 | /* |
908 | * Transfer objects in one arraycache to another. | |
909 | * Locking must be handled by the caller. | |
910 | * | |
911 | * Return the number of entries transferred. | |
912 | */ | |
913 | static int transfer_objects(struct array_cache *to, | |
914 | struct array_cache *from, unsigned int max) | |
915 | { | |
916 | /* Figure out how many entries to transfer */ | |
917 | int nr = min(min(from->avail, max), to->limit - to->avail); | |
918 | ||
919 | if (!nr) | |
920 | return 0; | |
921 | ||
922 | memcpy(to->entry + to->avail, from->entry + from->avail -nr, | |
923 | sizeof(void *) *nr); | |
924 | ||
925 | from->avail -= nr; | |
926 | to->avail += nr; | |
927 | to->touched = 1; | |
928 | return nr; | |
929 | } | |
930 | ||
e498be7d | 931 | #ifdef CONFIG_NUMA |
343e0d7a | 932 | static void *__cache_alloc_node(struct kmem_cache *, gfp_t, int); |
c61afb18 | 933 | static void *alternate_node_alloc(struct kmem_cache *, gfp_t); |
dc85da15 | 934 | |
5295a74c | 935 | static struct array_cache **alloc_alien_cache(int node, int limit) |
e498be7d CL |
936 | { |
937 | struct array_cache **ac_ptr; | |
b28a02de | 938 | int memsize = sizeof(void *) * MAX_NUMNODES; |
e498be7d CL |
939 | int i; |
940 | ||
941 | if (limit > 1) | |
942 | limit = 12; | |
943 | ac_ptr = kmalloc_node(memsize, GFP_KERNEL, node); | |
944 | if (ac_ptr) { | |
945 | for_each_node(i) { | |
946 | if (i == node || !node_online(i)) { | |
947 | ac_ptr[i] = NULL; | |
948 | continue; | |
949 | } | |
950 | ac_ptr[i] = alloc_arraycache(node, limit, 0xbaadf00d); | |
951 | if (!ac_ptr[i]) { | |
b28a02de | 952 | for (i--; i <= 0; i--) |
e498be7d CL |
953 | kfree(ac_ptr[i]); |
954 | kfree(ac_ptr); | |
955 | return NULL; | |
956 | } | |
957 | } | |
958 | } | |
959 | return ac_ptr; | |
960 | } | |
961 | ||
5295a74c | 962 | static void free_alien_cache(struct array_cache **ac_ptr) |
e498be7d CL |
963 | { |
964 | int i; | |
965 | ||
966 | if (!ac_ptr) | |
967 | return; | |
e498be7d | 968 | for_each_node(i) |
b28a02de | 969 | kfree(ac_ptr[i]); |
e498be7d CL |
970 | kfree(ac_ptr); |
971 | } | |
972 | ||
343e0d7a | 973 | static void __drain_alien_cache(struct kmem_cache *cachep, |
5295a74c | 974 | struct array_cache *ac, int node) |
e498be7d CL |
975 | { |
976 | struct kmem_list3 *rl3 = cachep->nodelists[node]; | |
977 | ||
978 | if (ac->avail) { | |
979 | spin_lock(&rl3->list_lock); | |
e00946fe CL |
980 | /* |
981 | * Stuff objects into the remote nodes shared array first. | |
982 | * That way we could avoid the overhead of putting the objects | |
983 | * into the free lists and getting them back later. | |
984 | */ | |
693f7d36 JS |
985 | if (rl3->shared) |
986 | transfer_objects(rl3->shared, ac, ac->limit); | |
e00946fe | 987 | |
ff69416e | 988 | free_block(cachep, ac->entry, ac->avail, node); |
e498be7d CL |
989 | ac->avail = 0; |
990 | spin_unlock(&rl3->list_lock); | |
991 | } | |
992 | } | |
993 | ||
8fce4d8e CL |
994 | /* |
995 | * Called from cache_reap() to regularly drain alien caches round robin. | |
996 | */ | |
997 | static void reap_alien(struct kmem_cache *cachep, struct kmem_list3 *l3) | |
998 | { | |
999 | int node = __get_cpu_var(reap_node); | |
1000 | ||
1001 | if (l3->alien) { | |
1002 | struct array_cache *ac = l3->alien[node]; | |
e00946fe CL |
1003 | |
1004 | if (ac && ac->avail && spin_trylock_irq(&ac->lock)) { | |
8fce4d8e CL |
1005 | __drain_alien_cache(cachep, ac, node); |
1006 | spin_unlock_irq(&ac->lock); | |
1007 | } | |
1008 | } | |
1009 | } | |
1010 | ||
a737b3e2 AM |
1011 | static void drain_alien_cache(struct kmem_cache *cachep, |
1012 | struct array_cache **alien) | |
e498be7d | 1013 | { |
b28a02de | 1014 | int i = 0; |
e498be7d CL |
1015 | struct array_cache *ac; |
1016 | unsigned long flags; | |
1017 | ||
1018 | for_each_online_node(i) { | |
4484ebf1 | 1019 | ac = alien[i]; |
e498be7d CL |
1020 | if (ac) { |
1021 | spin_lock_irqsave(&ac->lock, flags); | |
1022 | __drain_alien_cache(cachep, ac, i); | |
1023 | spin_unlock_irqrestore(&ac->lock, flags); | |
1024 | } | |
1025 | } | |
1026 | } | |
1027 | #else | |
7a21ef6f | 1028 | |
4484ebf1 | 1029 | #define drain_alien_cache(cachep, alien) do { } while (0) |
8fce4d8e | 1030 | #define reap_alien(cachep, l3) do { } while (0) |
4484ebf1 | 1031 | |
7a21ef6f LT |
1032 | static inline struct array_cache **alloc_alien_cache(int node, int limit) |
1033 | { | |
1034 | return (struct array_cache **) 0x01020304ul; | |
1035 | } | |
1036 | ||
4484ebf1 RT |
1037 | static inline void free_alien_cache(struct array_cache **ac_ptr) |
1038 | { | |
1039 | } | |
7a21ef6f | 1040 | |
e498be7d CL |
1041 | #endif |
1042 | ||
83d722f7 | 1043 | static int cpuup_callback(struct notifier_block *nfb, |
b28a02de | 1044 | unsigned long action, void *hcpu) |
1da177e4 LT |
1045 | { |
1046 | long cpu = (long)hcpu; | |
343e0d7a | 1047 | struct kmem_cache *cachep; |
e498be7d CL |
1048 | struct kmem_list3 *l3 = NULL; |
1049 | int node = cpu_to_node(cpu); | |
1050 | int memsize = sizeof(struct kmem_list3); | |
1da177e4 LT |
1051 | |
1052 | switch (action) { | |
1053 | case CPU_UP_PREPARE: | |
fc0abb14 | 1054 | mutex_lock(&cache_chain_mutex); |
a737b3e2 AM |
1055 | /* |
1056 | * We need to do this right in the beginning since | |
e498be7d CL |
1057 | * alloc_arraycache's are going to use this list. |
1058 | * kmalloc_node allows us to add the slab to the right | |
1059 | * kmem_list3 and not this cpu's kmem_list3 | |
1060 | */ | |
1061 | ||
1da177e4 | 1062 | list_for_each_entry(cachep, &cache_chain, next) { |
a737b3e2 AM |
1063 | /* |
1064 | * Set up the size64 kmemlist for cpu before we can | |
e498be7d CL |
1065 | * begin anything. Make sure some other cpu on this |
1066 | * node has not already allocated this | |
1067 | */ | |
1068 | if (!cachep->nodelists[node]) { | |
a737b3e2 AM |
1069 | l3 = kmalloc_node(memsize, GFP_KERNEL, node); |
1070 | if (!l3) | |
e498be7d CL |
1071 | goto bad; |
1072 | kmem_list3_init(l3); | |
1073 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + | |
b28a02de | 1074 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
e498be7d | 1075 | |
4484ebf1 RT |
1076 | /* |
1077 | * The l3s don't come and go as CPUs come and | |
1078 | * go. cache_chain_mutex is sufficient | |
1079 | * protection here. | |
1080 | */ | |
e498be7d CL |
1081 | cachep->nodelists[node] = l3; |
1082 | } | |
1da177e4 | 1083 | |
e498be7d CL |
1084 | spin_lock_irq(&cachep->nodelists[node]->list_lock); |
1085 | cachep->nodelists[node]->free_limit = | |
a737b3e2 AM |
1086 | (1 + nr_cpus_node(node)) * |
1087 | cachep->batchcount + cachep->num; | |
e498be7d CL |
1088 | spin_unlock_irq(&cachep->nodelists[node]->list_lock); |
1089 | } | |
1090 | ||
a737b3e2 AM |
1091 | /* |
1092 | * Now we can go ahead with allocating the shared arrays and | |
1093 | * array caches | |
1094 | */ | |
e498be7d | 1095 | list_for_each_entry(cachep, &cache_chain, next) { |
cd105df4 | 1096 | struct array_cache *nc; |
4484ebf1 RT |
1097 | struct array_cache *shared; |
1098 | struct array_cache **alien; | |
cd105df4 | 1099 | |
e498be7d | 1100 | nc = alloc_arraycache(node, cachep->limit, |
4484ebf1 | 1101 | cachep->batchcount); |
1da177e4 LT |
1102 | if (!nc) |
1103 | goto bad; | |
4484ebf1 RT |
1104 | shared = alloc_arraycache(node, |
1105 | cachep->shared * cachep->batchcount, | |
1106 | 0xbaadf00d); | |
1107 | if (!shared) | |
1108 | goto bad; | |
7a21ef6f | 1109 | |
4484ebf1 RT |
1110 | alien = alloc_alien_cache(node, cachep->limit); |
1111 | if (!alien) | |
1112 | goto bad; | |
1da177e4 | 1113 | cachep->array[cpu] = nc; |
e498be7d CL |
1114 | l3 = cachep->nodelists[node]; |
1115 | BUG_ON(!l3); | |
e498be7d | 1116 | |
4484ebf1 RT |
1117 | spin_lock_irq(&l3->list_lock); |
1118 | if (!l3->shared) { | |
1119 | /* | |
1120 | * We are serialised from CPU_DEAD or | |
1121 | * CPU_UP_CANCELLED by the cpucontrol lock | |
1122 | */ | |
1123 | l3->shared = shared; | |
1124 | shared = NULL; | |
e498be7d | 1125 | } |
4484ebf1 RT |
1126 | #ifdef CONFIG_NUMA |
1127 | if (!l3->alien) { | |
1128 | l3->alien = alien; | |
1129 | alien = NULL; | |
1130 | } | |
1131 | #endif | |
1132 | spin_unlock_irq(&l3->list_lock); | |
4484ebf1 RT |
1133 | kfree(shared); |
1134 | free_alien_cache(alien); | |
1da177e4 | 1135 | } |
fc0abb14 | 1136 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1137 | break; |
1138 | case CPU_ONLINE: | |
1139 | start_cpu_timer(cpu); | |
1140 | break; | |
1141 | #ifdef CONFIG_HOTPLUG_CPU | |
1142 | case CPU_DEAD: | |
4484ebf1 RT |
1143 | /* |
1144 | * Even if all the cpus of a node are down, we don't free the | |
1145 | * kmem_list3 of any cache. This to avoid a race between | |
1146 | * cpu_down, and a kmalloc allocation from another cpu for | |
1147 | * memory from the node of the cpu going down. The list3 | |
1148 | * structure is usually allocated from kmem_cache_create() and | |
1149 | * gets destroyed at kmem_cache_destroy(). | |
1150 | */ | |
1da177e4 LT |
1151 | /* fall thru */ |
1152 | case CPU_UP_CANCELED: | |
fc0abb14 | 1153 | mutex_lock(&cache_chain_mutex); |
1da177e4 LT |
1154 | list_for_each_entry(cachep, &cache_chain, next) { |
1155 | struct array_cache *nc; | |
4484ebf1 RT |
1156 | struct array_cache *shared; |
1157 | struct array_cache **alien; | |
e498be7d | 1158 | cpumask_t mask; |
1da177e4 | 1159 | |
e498be7d | 1160 | mask = node_to_cpumask(node); |
1da177e4 LT |
1161 | /* cpu is dead; no one can alloc from it. */ |
1162 | nc = cachep->array[cpu]; | |
1163 | cachep->array[cpu] = NULL; | |
e498be7d CL |
1164 | l3 = cachep->nodelists[node]; |
1165 | ||
1166 | if (!l3) | |
4484ebf1 | 1167 | goto free_array_cache; |
e498be7d | 1168 | |
ca3b9b91 | 1169 | spin_lock_irq(&l3->list_lock); |
e498be7d CL |
1170 | |
1171 | /* Free limit for this kmem_list3 */ | |
1172 | l3->free_limit -= cachep->batchcount; | |
1173 | if (nc) | |
ff69416e | 1174 | free_block(cachep, nc->entry, nc->avail, node); |
e498be7d CL |
1175 | |
1176 | if (!cpus_empty(mask)) { | |
ca3b9b91 | 1177 | spin_unlock_irq(&l3->list_lock); |
4484ebf1 | 1178 | goto free_array_cache; |
b28a02de | 1179 | } |
e498be7d | 1180 | |
4484ebf1 RT |
1181 | shared = l3->shared; |
1182 | if (shared) { | |
e498be7d | 1183 | free_block(cachep, l3->shared->entry, |
b28a02de | 1184 | l3->shared->avail, node); |
e498be7d CL |
1185 | l3->shared = NULL; |
1186 | } | |
e498be7d | 1187 | |
4484ebf1 RT |
1188 | alien = l3->alien; |
1189 | l3->alien = NULL; | |
1190 | ||
1191 | spin_unlock_irq(&l3->list_lock); | |
1192 | ||
1193 | kfree(shared); | |
1194 | if (alien) { | |
1195 | drain_alien_cache(cachep, alien); | |
1196 | free_alien_cache(alien); | |
e498be7d | 1197 | } |
4484ebf1 | 1198 | free_array_cache: |
1da177e4 LT |
1199 | kfree(nc); |
1200 | } | |
4484ebf1 RT |
1201 | /* |
1202 | * In the previous loop, all the objects were freed to | |
1203 | * the respective cache's slabs, now we can go ahead and | |
1204 | * shrink each nodelist to its limit. | |
1205 | */ | |
1206 | list_for_each_entry(cachep, &cache_chain, next) { | |
1207 | l3 = cachep->nodelists[node]; | |
1208 | if (!l3) | |
1209 | continue; | |
1210 | spin_lock_irq(&l3->list_lock); | |
1211 | /* free slabs belonging to this node */ | |
1212 | __node_shrink(cachep, node); | |
1213 | spin_unlock_irq(&l3->list_lock); | |
1214 | } | |
fc0abb14 | 1215 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1216 | break; |
1217 | #endif | |
1218 | } | |
1219 | return NOTIFY_OK; | |
a737b3e2 | 1220 | bad: |
fc0abb14 | 1221 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1222 | return NOTIFY_BAD; |
1223 | } | |
1224 | ||
1225 | static struct notifier_block cpucache_notifier = { &cpuup_callback, NULL, 0 }; | |
1226 | ||
e498be7d CL |
1227 | /* |
1228 | * swap the static kmem_list3 with kmalloced memory | |
1229 | */ | |
a737b3e2 AM |
1230 | static void init_list(struct kmem_cache *cachep, struct kmem_list3 *list, |
1231 | int nodeid) | |
e498be7d CL |
1232 | { |
1233 | struct kmem_list3 *ptr; | |
1234 | ||
1235 | BUG_ON(cachep->nodelists[nodeid] != list); | |
1236 | ptr = kmalloc_node(sizeof(struct kmem_list3), GFP_KERNEL, nodeid); | |
1237 | BUG_ON(!ptr); | |
1238 | ||
1239 | local_irq_disable(); | |
1240 | memcpy(ptr, list, sizeof(struct kmem_list3)); | |
1241 | MAKE_ALL_LISTS(cachep, ptr, nodeid); | |
1242 | cachep->nodelists[nodeid] = ptr; | |
1243 | local_irq_enable(); | |
1244 | } | |
1245 | ||
a737b3e2 AM |
1246 | /* |
1247 | * Initialisation. Called after the page allocator have been initialised and | |
1248 | * before smp_init(). | |
1da177e4 LT |
1249 | */ |
1250 | void __init kmem_cache_init(void) | |
1251 | { | |
1252 | size_t left_over; | |
1253 | struct cache_sizes *sizes; | |
1254 | struct cache_names *names; | |
e498be7d | 1255 | int i; |
07ed76b2 | 1256 | int order; |
e498be7d CL |
1257 | |
1258 | for (i = 0; i < NUM_INIT_LISTS; i++) { | |
1259 | kmem_list3_init(&initkmem_list3[i]); | |
1260 | if (i < MAX_NUMNODES) | |
1261 | cache_cache.nodelists[i] = NULL; | |
1262 | } | |
1da177e4 LT |
1263 | |
1264 | /* | |
1265 | * Fragmentation resistance on low memory - only use bigger | |
1266 | * page orders on machines with more than 32MB of memory. | |
1267 | */ | |
1268 | if (num_physpages > (32 << 20) >> PAGE_SHIFT) | |
1269 | slab_break_gfp_order = BREAK_GFP_ORDER_HI; | |
1270 | ||
1da177e4 LT |
1271 | /* Bootstrap is tricky, because several objects are allocated |
1272 | * from caches that do not exist yet: | |
a737b3e2 AM |
1273 | * 1) initialize the cache_cache cache: it contains the struct |
1274 | * kmem_cache structures of all caches, except cache_cache itself: | |
1275 | * cache_cache is statically allocated. | |
e498be7d CL |
1276 | * Initially an __init data area is used for the head array and the |
1277 | * kmem_list3 structures, it's replaced with a kmalloc allocated | |
1278 | * array at the end of the bootstrap. | |
1da177e4 | 1279 | * 2) Create the first kmalloc cache. |
343e0d7a | 1280 | * The struct kmem_cache for the new cache is allocated normally. |
e498be7d CL |
1281 | * An __init data area is used for the head array. |
1282 | * 3) Create the remaining kmalloc caches, with minimally sized | |
1283 | * head arrays. | |
1da177e4 LT |
1284 | * 4) Replace the __init data head arrays for cache_cache and the first |
1285 | * kmalloc cache with kmalloc allocated arrays. | |
e498be7d CL |
1286 | * 5) Replace the __init data for kmem_list3 for cache_cache and |
1287 | * the other cache's with kmalloc allocated memory. | |
1288 | * 6) Resize the head arrays of the kmalloc caches to their final sizes. | |
1da177e4 LT |
1289 | */ |
1290 | ||
1291 | /* 1) create the cache_cache */ | |
1da177e4 LT |
1292 | INIT_LIST_HEAD(&cache_chain); |
1293 | list_add(&cache_cache.next, &cache_chain); | |
1294 | cache_cache.colour_off = cache_line_size(); | |
1295 | cache_cache.array[smp_processor_id()] = &initarray_cache.cache; | |
e498be7d | 1296 | cache_cache.nodelists[numa_node_id()] = &initkmem_list3[CACHE_CACHE]; |
1da177e4 | 1297 | |
a737b3e2 AM |
1298 | cache_cache.buffer_size = ALIGN(cache_cache.buffer_size, |
1299 | cache_line_size()); | |
1da177e4 | 1300 | |
07ed76b2 JS |
1301 | for (order = 0; order < MAX_ORDER; order++) { |
1302 | cache_estimate(order, cache_cache.buffer_size, | |
1303 | cache_line_size(), 0, &left_over, &cache_cache.num); | |
1304 | if (cache_cache.num) | |
1305 | break; | |
1306 | } | |
40094fa6 | 1307 | BUG_ON(!cache_cache.num); |
07ed76b2 | 1308 | cache_cache.gfporder = order; |
b28a02de | 1309 | cache_cache.colour = left_over / cache_cache.colour_off; |
b28a02de PE |
1310 | cache_cache.slab_size = ALIGN(cache_cache.num * sizeof(kmem_bufctl_t) + |
1311 | sizeof(struct slab), cache_line_size()); | |
1da177e4 LT |
1312 | |
1313 | /* 2+3) create the kmalloc caches */ | |
1314 | sizes = malloc_sizes; | |
1315 | names = cache_names; | |
1316 | ||
a737b3e2 AM |
1317 | /* |
1318 | * Initialize the caches that provide memory for the array cache and the | |
1319 | * kmem_list3 structures first. Without this, further allocations will | |
1320 | * bug. | |
e498be7d CL |
1321 | */ |
1322 | ||
1323 | sizes[INDEX_AC].cs_cachep = kmem_cache_create(names[INDEX_AC].name, | |
a737b3e2 AM |
1324 | sizes[INDEX_AC].cs_size, |
1325 | ARCH_KMALLOC_MINALIGN, | |
1326 | ARCH_KMALLOC_FLAGS|SLAB_PANIC, | |
1327 | NULL, NULL); | |
e498be7d | 1328 | |
a737b3e2 | 1329 | if (INDEX_AC != INDEX_L3) { |
e498be7d | 1330 | sizes[INDEX_L3].cs_cachep = |
a737b3e2 AM |
1331 | kmem_cache_create(names[INDEX_L3].name, |
1332 | sizes[INDEX_L3].cs_size, | |
1333 | ARCH_KMALLOC_MINALIGN, | |
1334 | ARCH_KMALLOC_FLAGS|SLAB_PANIC, | |
1335 | NULL, NULL); | |
1336 | } | |
e498be7d | 1337 | |
1da177e4 | 1338 | while (sizes->cs_size != ULONG_MAX) { |
e498be7d CL |
1339 | /* |
1340 | * For performance, all the general caches are L1 aligned. | |
1da177e4 LT |
1341 | * This should be particularly beneficial on SMP boxes, as it |
1342 | * eliminates "false sharing". | |
1343 | * Note for systems short on memory removing the alignment will | |
e498be7d CL |
1344 | * allow tighter packing of the smaller caches. |
1345 | */ | |
a737b3e2 | 1346 | if (!sizes->cs_cachep) { |
e498be7d | 1347 | sizes->cs_cachep = kmem_cache_create(names->name, |
a737b3e2 AM |
1348 | sizes->cs_size, |
1349 | ARCH_KMALLOC_MINALIGN, | |
1350 | ARCH_KMALLOC_FLAGS|SLAB_PANIC, | |
1351 | NULL, NULL); | |
1352 | } | |
1da177e4 | 1353 | |
1da177e4 | 1354 | sizes->cs_dmacachep = kmem_cache_create(names->name_dma, |
a737b3e2 AM |
1355 | sizes->cs_size, |
1356 | ARCH_KMALLOC_MINALIGN, | |
1357 | ARCH_KMALLOC_FLAGS|SLAB_CACHE_DMA| | |
1358 | SLAB_PANIC, | |
1359 | NULL, NULL); | |
1da177e4 LT |
1360 | sizes++; |
1361 | names++; | |
1362 | } | |
1363 | /* 4) Replace the bootstrap head arrays */ | |
1364 | { | |
b28a02de | 1365 | void *ptr; |
e498be7d | 1366 | |
1da177e4 | 1367 | ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d | 1368 | |
1da177e4 | 1369 | local_irq_disable(); |
9a2dba4b PE |
1370 | BUG_ON(cpu_cache_get(&cache_cache) != &initarray_cache.cache); |
1371 | memcpy(ptr, cpu_cache_get(&cache_cache), | |
b28a02de | 1372 | sizeof(struct arraycache_init)); |
1da177e4 LT |
1373 | cache_cache.array[smp_processor_id()] = ptr; |
1374 | local_irq_enable(); | |
e498be7d | 1375 | |
1da177e4 | 1376 | ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d | 1377 | |
1da177e4 | 1378 | local_irq_disable(); |
9a2dba4b | 1379 | BUG_ON(cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep) |
b28a02de | 1380 | != &initarray_generic.cache); |
9a2dba4b | 1381 | memcpy(ptr, cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep), |
b28a02de | 1382 | sizeof(struct arraycache_init)); |
e498be7d | 1383 | malloc_sizes[INDEX_AC].cs_cachep->array[smp_processor_id()] = |
b28a02de | 1384 | ptr; |
1da177e4 LT |
1385 | local_irq_enable(); |
1386 | } | |
e498be7d CL |
1387 | /* 5) Replace the bootstrap kmem_list3's */ |
1388 | { | |
1389 | int node; | |
1390 | /* Replace the static kmem_list3 structures for the boot cpu */ | |
1391 | init_list(&cache_cache, &initkmem_list3[CACHE_CACHE], | |
b28a02de | 1392 | numa_node_id()); |
e498be7d CL |
1393 | |
1394 | for_each_online_node(node) { | |
1395 | init_list(malloc_sizes[INDEX_AC].cs_cachep, | |
b28a02de | 1396 | &initkmem_list3[SIZE_AC + node], node); |
e498be7d CL |
1397 | |
1398 | if (INDEX_AC != INDEX_L3) { | |
1399 | init_list(malloc_sizes[INDEX_L3].cs_cachep, | |
b28a02de PE |
1400 | &initkmem_list3[SIZE_L3 + node], |
1401 | node); | |
e498be7d CL |
1402 | } |
1403 | } | |
1404 | } | |
1da177e4 | 1405 | |
e498be7d | 1406 | /* 6) resize the head arrays to their final sizes */ |
1da177e4 | 1407 | { |
343e0d7a | 1408 | struct kmem_cache *cachep; |
fc0abb14 | 1409 | mutex_lock(&cache_chain_mutex); |
1da177e4 | 1410 | list_for_each_entry(cachep, &cache_chain, next) |
a737b3e2 | 1411 | enable_cpucache(cachep); |
fc0abb14 | 1412 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1413 | } |
1414 | ||
1415 | /* Done! */ | |
1416 | g_cpucache_up = FULL; | |
1417 | ||
a737b3e2 AM |
1418 | /* |
1419 | * Register a cpu startup notifier callback that initializes | |
1420 | * cpu_cache_get for all new cpus | |
1da177e4 LT |
1421 | */ |
1422 | register_cpu_notifier(&cpucache_notifier); | |
1da177e4 | 1423 | |
a737b3e2 AM |
1424 | /* |
1425 | * The reap timers are started later, with a module init call: That part | |
1426 | * of the kernel is not yet operational. | |
1da177e4 LT |
1427 | */ |
1428 | } | |
1429 | ||
1430 | static int __init cpucache_init(void) | |
1431 | { | |
1432 | int cpu; | |
1433 | ||
a737b3e2 AM |
1434 | /* |
1435 | * Register the timers that return unneeded pages to the page allocator | |
1da177e4 | 1436 | */ |
e498be7d | 1437 | for_each_online_cpu(cpu) |
a737b3e2 | 1438 | start_cpu_timer(cpu); |
1da177e4 LT |
1439 | return 0; |
1440 | } | |
1da177e4 LT |
1441 | __initcall(cpucache_init); |
1442 | ||
1443 | /* | |
1444 | * Interface to system's page allocator. No need to hold the cache-lock. | |
1445 | * | |
1446 | * If we requested dmaable memory, we will get it. Even if we | |
1447 | * did not request dmaable memory, we might get it, but that | |
1448 | * would be relatively rare and ignorable. | |
1449 | */ | |
343e0d7a | 1450 | static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 LT |
1451 | { |
1452 | struct page *page; | |
1453 | void *addr; | |
1454 | int i; | |
1455 | ||
1456 | flags |= cachep->gfpflags; | |
d6fef9da LY |
1457 | #ifndef CONFIG_MMU |
1458 | /* nommu uses slab's for process anonymous memory allocations, so | |
1459 | * requires __GFP_COMP to properly refcount higher order allocations" | |
1460 | */ | |
1461 | page = alloc_pages_node(nodeid, (flags | __GFP_COMP), cachep->gfporder); | |
1462 | #else | |
50c85a19 | 1463 | page = alloc_pages_node(nodeid, flags, cachep->gfporder); |
d6fef9da | 1464 | #endif |
1da177e4 LT |
1465 | if (!page) |
1466 | return NULL; | |
1467 | addr = page_address(page); | |
1468 | ||
1469 | i = (1 << cachep->gfporder); | |
1470 | if (cachep->flags & SLAB_RECLAIM_ACCOUNT) | |
1471 | atomic_add(i, &slab_reclaim_pages); | |
1472 | add_page_state(nr_slab, i); | |
1473 | while (i--) { | |
f205b2fe | 1474 | __SetPageSlab(page); |
1da177e4 LT |
1475 | page++; |
1476 | } | |
1477 | return addr; | |
1478 | } | |
1479 | ||
1480 | /* | |
1481 | * Interface to system's page release. | |
1482 | */ | |
343e0d7a | 1483 | static void kmem_freepages(struct kmem_cache *cachep, void *addr) |
1da177e4 | 1484 | { |
b28a02de | 1485 | unsigned long i = (1 << cachep->gfporder); |
1da177e4 LT |
1486 | struct page *page = virt_to_page(addr); |
1487 | const unsigned long nr_freed = i; | |
1488 | ||
1489 | while (i--) { | |
f205b2fe NP |
1490 | BUG_ON(!PageSlab(page)); |
1491 | __ClearPageSlab(page); | |
1da177e4 LT |
1492 | page++; |
1493 | } | |
1494 | sub_page_state(nr_slab, nr_freed); | |
1495 | if (current->reclaim_state) | |
1496 | current->reclaim_state->reclaimed_slab += nr_freed; | |
1497 | free_pages((unsigned long)addr, cachep->gfporder); | |
b28a02de PE |
1498 | if (cachep->flags & SLAB_RECLAIM_ACCOUNT) |
1499 | atomic_sub(1 << cachep->gfporder, &slab_reclaim_pages); | |
1da177e4 LT |
1500 | } |
1501 | ||
1502 | static void kmem_rcu_free(struct rcu_head *head) | |
1503 | { | |
b28a02de | 1504 | struct slab_rcu *slab_rcu = (struct slab_rcu *)head; |
343e0d7a | 1505 | struct kmem_cache *cachep = slab_rcu->cachep; |
1da177e4 LT |
1506 | |
1507 | kmem_freepages(cachep, slab_rcu->addr); | |
1508 | if (OFF_SLAB(cachep)) | |
1509 | kmem_cache_free(cachep->slabp_cache, slab_rcu); | |
1510 | } | |
1511 | ||
1512 | #if DEBUG | |
1513 | ||
1514 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
343e0d7a | 1515 | static void store_stackinfo(struct kmem_cache *cachep, unsigned long *addr, |
b28a02de | 1516 | unsigned long caller) |
1da177e4 | 1517 | { |
3dafccf2 | 1518 | int size = obj_size(cachep); |
1da177e4 | 1519 | |
3dafccf2 | 1520 | addr = (unsigned long *)&((char *)addr)[obj_offset(cachep)]; |
1da177e4 | 1521 | |
b28a02de | 1522 | if (size < 5 * sizeof(unsigned long)) |
1da177e4 LT |
1523 | return; |
1524 | ||
b28a02de PE |
1525 | *addr++ = 0x12345678; |
1526 | *addr++ = caller; | |
1527 | *addr++ = smp_processor_id(); | |
1528 | size -= 3 * sizeof(unsigned long); | |
1da177e4 LT |
1529 | { |
1530 | unsigned long *sptr = &caller; | |
1531 | unsigned long svalue; | |
1532 | ||
1533 | while (!kstack_end(sptr)) { | |
1534 | svalue = *sptr++; | |
1535 | if (kernel_text_address(svalue)) { | |
b28a02de | 1536 | *addr++ = svalue; |
1da177e4 LT |
1537 | size -= sizeof(unsigned long); |
1538 | if (size <= sizeof(unsigned long)) | |
1539 | break; | |
1540 | } | |
1541 | } | |
1542 | ||
1543 | } | |
b28a02de | 1544 | *addr++ = 0x87654321; |
1da177e4 LT |
1545 | } |
1546 | #endif | |
1547 | ||
343e0d7a | 1548 | static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) |
1da177e4 | 1549 | { |
3dafccf2 MS |
1550 | int size = obj_size(cachep); |
1551 | addr = &((char *)addr)[obj_offset(cachep)]; | |
1da177e4 LT |
1552 | |
1553 | memset(addr, val, size); | |
b28a02de | 1554 | *(unsigned char *)(addr + size - 1) = POISON_END; |
1da177e4 LT |
1555 | } |
1556 | ||
1557 | static void dump_line(char *data, int offset, int limit) | |
1558 | { | |
1559 | int i; | |
1560 | printk(KERN_ERR "%03x:", offset); | |
a737b3e2 | 1561 | for (i = 0; i < limit; i++) |
b28a02de | 1562 | printk(" %02x", (unsigned char)data[offset + i]); |
1da177e4 LT |
1563 | printk("\n"); |
1564 | } | |
1565 | #endif | |
1566 | ||
1567 | #if DEBUG | |
1568 | ||
343e0d7a | 1569 | static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines) |
1da177e4 LT |
1570 | { |
1571 | int i, size; | |
1572 | char *realobj; | |
1573 | ||
1574 | if (cachep->flags & SLAB_RED_ZONE) { | |
1575 | printk(KERN_ERR "Redzone: 0x%lx/0x%lx.\n", | |
a737b3e2 AM |
1576 | *dbg_redzone1(cachep, objp), |
1577 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
1578 | } |
1579 | ||
1580 | if (cachep->flags & SLAB_STORE_USER) { | |
1581 | printk(KERN_ERR "Last user: [<%p>]", | |
a737b3e2 | 1582 | *dbg_userword(cachep, objp)); |
1da177e4 | 1583 | print_symbol("(%s)", |
a737b3e2 | 1584 | (unsigned long)*dbg_userword(cachep, objp)); |
1da177e4 LT |
1585 | printk("\n"); |
1586 | } | |
3dafccf2 MS |
1587 | realobj = (char *)objp + obj_offset(cachep); |
1588 | size = obj_size(cachep); | |
b28a02de | 1589 | for (i = 0; i < size && lines; i += 16, lines--) { |
1da177e4 LT |
1590 | int limit; |
1591 | limit = 16; | |
b28a02de PE |
1592 | if (i + limit > size) |
1593 | limit = size - i; | |
1da177e4 LT |
1594 | dump_line(realobj, i, limit); |
1595 | } | |
1596 | } | |
1597 | ||
343e0d7a | 1598 | static void check_poison_obj(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
1599 | { |
1600 | char *realobj; | |
1601 | int size, i; | |
1602 | int lines = 0; | |
1603 | ||
3dafccf2 MS |
1604 | realobj = (char *)objp + obj_offset(cachep); |
1605 | size = obj_size(cachep); | |
1da177e4 | 1606 | |
b28a02de | 1607 | for (i = 0; i < size; i++) { |
1da177e4 | 1608 | char exp = POISON_FREE; |
b28a02de | 1609 | if (i == size - 1) |
1da177e4 LT |
1610 | exp = POISON_END; |
1611 | if (realobj[i] != exp) { | |
1612 | int limit; | |
1613 | /* Mismatch ! */ | |
1614 | /* Print header */ | |
1615 | if (lines == 0) { | |
b28a02de | 1616 | printk(KERN_ERR |
a737b3e2 AM |
1617 | "Slab corruption: start=%p, len=%d\n", |
1618 | realobj, size); | |
1da177e4 LT |
1619 | print_objinfo(cachep, objp, 0); |
1620 | } | |
1621 | /* Hexdump the affected line */ | |
b28a02de | 1622 | i = (i / 16) * 16; |
1da177e4 | 1623 | limit = 16; |
b28a02de PE |
1624 | if (i + limit > size) |
1625 | limit = size - i; | |
1da177e4 LT |
1626 | dump_line(realobj, i, limit); |
1627 | i += 16; | |
1628 | lines++; | |
1629 | /* Limit to 5 lines */ | |
1630 | if (lines > 5) | |
1631 | break; | |
1632 | } | |
1633 | } | |
1634 | if (lines != 0) { | |
1635 | /* Print some data about the neighboring objects, if they | |
1636 | * exist: | |
1637 | */ | |
6ed5eb22 | 1638 | struct slab *slabp = virt_to_slab(objp); |
8fea4e96 | 1639 | unsigned int objnr; |
1da177e4 | 1640 | |
8fea4e96 | 1641 | objnr = obj_to_index(cachep, slabp, objp); |
1da177e4 | 1642 | if (objnr) { |
8fea4e96 | 1643 | objp = index_to_obj(cachep, slabp, objnr - 1); |
3dafccf2 | 1644 | realobj = (char *)objp + obj_offset(cachep); |
1da177e4 | 1645 | printk(KERN_ERR "Prev obj: start=%p, len=%d\n", |
b28a02de | 1646 | realobj, size); |
1da177e4 LT |
1647 | print_objinfo(cachep, objp, 2); |
1648 | } | |
b28a02de | 1649 | if (objnr + 1 < cachep->num) { |
8fea4e96 | 1650 | objp = index_to_obj(cachep, slabp, objnr + 1); |
3dafccf2 | 1651 | realobj = (char *)objp + obj_offset(cachep); |
1da177e4 | 1652 | printk(KERN_ERR "Next obj: start=%p, len=%d\n", |
b28a02de | 1653 | realobj, size); |
1da177e4 LT |
1654 | print_objinfo(cachep, objp, 2); |
1655 | } | |
1656 | } | |
1657 | } | |
1658 | #endif | |
1659 | ||
12dd36fa MD |
1660 | #if DEBUG |
1661 | /** | |
911851e6 RD |
1662 | * slab_destroy_objs - destroy a slab and its objects |
1663 | * @cachep: cache pointer being destroyed | |
1664 | * @slabp: slab pointer being destroyed | |
1665 | * | |
1666 | * Call the registered destructor for each object in a slab that is being | |
1667 | * destroyed. | |
1da177e4 | 1668 | */ |
343e0d7a | 1669 | static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp) |
1da177e4 | 1670 | { |
1da177e4 LT |
1671 | int i; |
1672 | for (i = 0; i < cachep->num; i++) { | |
8fea4e96 | 1673 | void *objp = index_to_obj(cachep, slabp, i); |
1da177e4 LT |
1674 | |
1675 | if (cachep->flags & SLAB_POISON) { | |
1676 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
a737b3e2 AM |
1677 | if (cachep->buffer_size % PAGE_SIZE == 0 && |
1678 | OFF_SLAB(cachep)) | |
b28a02de | 1679 | kernel_map_pages(virt_to_page(objp), |
a737b3e2 | 1680 | cachep->buffer_size / PAGE_SIZE, 1); |
1da177e4 LT |
1681 | else |
1682 | check_poison_obj(cachep, objp); | |
1683 | #else | |
1684 | check_poison_obj(cachep, objp); | |
1685 | #endif | |
1686 | } | |
1687 | if (cachep->flags & SLAB_RED_ZONE) { | |
1688 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) | |
1689 | slab_error(cachep, "start of a freed object " | |
b28a02de | 1690 | "was overwritten"); |
1da177e4 LT |
1691 | if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) |
1692 | slab_error(cachep, "end of a freed object " | |
b28a02de | 1693 | "was overwritten"); |
1da177e4 LT |
1694 | } |
1695 | if (cachep->dtor && !(cachep->flags & SLAB_POISON)) | |
3dafccf2 | 1696 | (cachep->dtor) (objp + obj_offset(cachep), cachep, 0); |
1da177e4 | 1697 | } |
12dd36fa | 1698 | } |
1da177e4 | 1699 | #else |
343e0d7a | 1700 | static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp) |
12dd36fa | 1701 | { |
1da177e4 LT |
1702 | if (cachep->dtor) { |
1703 | int i; | |
1704 | for (i = 0; i < cachep->num; i++) { | |
8fea4e96 | 1705 | void *objp = index_to_obj(cachep, slabp, i); |
b28a02de | 1706 | (cachep->dtor) (objp, cachep, 0); |
1da177e4 LT |
1707 | } |
1708 | } | |
12dd36fa | 1709 | } |
1da177e4 LT |
1710 | #endif |
1711 | ||
911851e6 RD |
1712 | /** |
1713 | * slab_destroy - destroy and release all objects in a slab | |
1714 | * @cachep: cache pointer being destroyed | |
1715 | * @slabp: slab pointer being destroyed | |
1716 | * | |
12dd36fa | 1717 | * Destroy all the objs in a slab, and release the mem back to the system. |
a737b3e2 AM |
1718 | * Before calling the slab must have been unlinked from the cache. The |
1719 | * cache-lock is not held/needed. | |
12dd36fa | 1720 | */ |
343e0d7a | 1721 | static void slab_destroy(struct kmem_cache *cachep, struct slab *slabp) |
12dd36fa MD |
1722 | { |
1723 | void *addr = slabp->s_mem - slabp->colouroff; | |
1724 | ||
1725 | slab_destroy_objs(cachep, slabp); | |
1da177e4 LT |
1726 | if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) { |
1727 | struct slab_rcu *slab_rcu; | |
1728 | ||
b28a02de | 1729 | slab_rcu = (struct slab_rcu *)slabp; |
1da177e4 LT |
1730 | slab_rcu->cachep = cachep; |
1731 | slab_rcu->addr = addr; | |
1732 | call_rcu(&slab_rcu->head, kmem_rcu_free); | |
1733 | } else { | |
1734 | kmem_freepages(cachep, addr); | |
1735 | if (OFF_SLAB(cachep)) | |
1736 | kmem_cache_free(cachep->slabp_cache, slabp); | |
1737 | } | |
1738 | } | |
1739 | ||
a737b3e2 AM |
1740 | /* |
1741 | * For setting up all the kmem_list3s for cache whose buffer_size is same as | |
1742 | * size of kmem_list3. | |
1743 | */ | |
343e0d7a | 1744 | static void set_up_list3s(struct kmem_cache *cachep, int index) |
e498be7d CL |
1745 | { |
1746 | int node; | |
1747 | ||
1748 | for_each_online_node(node) { | |
b28a02de | 1749 | cachep->nodelists[node] = &initkmem_list3[index + node]; |
e498be7d | 1750 | cachep->nodelists[node]->next_reap = jiffies + |
b28a02de PE |
1751 | REAPTIMEOUT_LIST3 + |
1752 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; | |
e498be7d CL |
1753 | } |
1754 | } | |
1755 | ||
4d268eba | 1756 | /** |
a70773dd RD |
1757 | * calculate_slab_order - calculate size (page order) of slabs |
1758 | * @cachep: pointer to the cache that is being created | |
1759 | * @size: size of objects to be created in this cache. | |
1760 | * @align: required alignment for the objects. | |
1761 | * @flags: slab allocation flags | |
1762 | * | |
1763 | * Also calculates the number of objects per slab. | |
4d268eba PE |
1764 | * |
1765 | * This could be made much more intelligent. For now, try to avoid using | |
1766 | * high order pages for slabs. When the gfp() functions are more friendly | |
1767 | * towards high-order requests, this should be changed. | |
1768 | */ | |
a737b3e2 | 1769 | static size_t calculate_slab_order(struct kmem_cache *cachep, |
ee13d785 | 1770 | size_t size, size_t align, unsigned long flags) |
4d268eba | 1771 | { |
b1ab41c4 | 1772 | unsigned long offslab_limit; |
4d268eba | 1773 | size_t left_over = 0; |
9888e6fa | 1774 | int gfporder; |
4d268eba | 1775 | |
a737b3e2 | 1776 | for (gfporder = 0; gfporder <= MAX_GFP_ORDER; gfporder++) { |
4d268eba PE |
1777 | unsigned int num; |
1778 | size_t remainder; | |
1779 | ||
9888e6fa | 1780 | cache_estimate(gfporder, size, align, flags, &remainder, &num); |
4d268eba PE |
1781 | if (!num) |
1782 | continue; | |
9888e6fa | 1783 | |
b1ab41c4 IM |
1784 | if (flags & CFLGS_OFF_SLAB) { |
1785 | /* | |
1786 | * Max number of objs-per-slab for caches which | |
1787 | * use off-slab slabs. Needed to avoid a possible | |
1788 | * looping condition in cache_grow(). | |
1789 | */ | |
1790 | offslab_limit = size - sizeof(struct slab); | |
1791 | offslab_limit /= sizeof(kmem_bufctl_t); | |
1792 | ||
1793 | if (num > offslab_limit) | |
1794 | break; | |
1795 | } | |
4d268eba | 1796 | |
9888e6fa | 1797 | /* Found something acceptable - save it away */ |
4d268eba | 1798 | cachep->num = num; |
9888e6fa | 1799 | cachep->gfporder = gfporder; |
4d268eba PE |
1800 | left_over = remainder; |
1801 | ||
f78bb8ad LT |
1802 | /* |
1803 | * A VFS-reclaimable slab tends to have most allocations | |
1804 | * as GFP_NOFS and we really don't want to have to be allocating | |
1805 | * higher-order pages when we are unable to shrink dcache. | |
1806 | */ | |
1807 | if (flags & SLAB_RECLAIM_ACCOUNT) | |
1808 | break; | |
1809 | ||
4d268eba PE |
1810 | /* |
1811 | * Large number of objects is good, but very large slabs are | |
1812 | * currently bad for the gfp()s. | |
1813 | */ | |
9888e6fa | 1814 | if (gfporder >= slab_break_gfp_order) |
4d268eba PE |
1815 | break; |
1816 | ||
9888e6fa LT |
1817 | /* |
1818 | * Acceptable internal fragmentation? | |
1819 | */ | |
a737b3e2 | 1820 | if (left_over * 8 <= (PAGE_SIZE << gfporder)) |
4d268eba PE |
1821 | break; |
1822 | } | |
1823 | return left_over; | |
1824 | } | |
1825 | ||
f30cf7d1 PE |
1826 | static void setup_cpu_cache(struct kmem_cache *cachep) |
1827 | { | |
1828 | if (g_cpucache_up == FULL) { | |
1829 | enable_cpucache(cachep); | |
1830 | return; | |
1831 | } | |
1832 | if (g_cpucache_up == NONE) { | |
1833 | /* | |
1834 | * Note: the first kmem_cache_create must create the cache | |
1835 | * that's used by kmalloc(24), otherwise the creation of | |
1836 | * further caches will BUG(). | |
1837 | */ | |
1838 | cachep->array[smp_processor_id()] = &initarray_generic.cache; | |
1839 | ||
1840 | /* | |
1841 | * If the cache that's used by kmalloc(sizeof(kmem_list3)) is | |
1842 | * the first cache, then we need to set up all its list3s, | |
1843 | * otherwise the creation of further caches will BUG(). | |
1844 | */ | |
1845 | set_up_list3s(cachep, SIZE_AC); | |
1846 | if (INDEX_AC == INDEX_L3) | |
1847 | g_cpucache_up = PARTIAL_L3; | |
1848 | else | |
1849 | g_cpucache_up = PARTIAL_AC; | |
1850 | } else { | |
1851 | cachep->array[smp_processor_id()] = | |
1852 | kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); | |
1853 | ||
1854 | if (g_cpucache_up == PARTIAL_AC) { | |
1855 | set_up_list3s(cachep, SIZE_L3); | |
1856 | g_cpucache_up = PARTIAL_L3; | |
1857 | } else { | |
1858 | int node; | |
1859 | for_each_online_node(node) { | |
1860 | cachep->nodelists[node] = | |
1861 | kmalloc_node(sizeof(struct kmem_list3), | |
1862 | GFP_KERNEL, node); | |
1863 | BUG_ON(!cachep->nodelists[node]); | |
1864 | kmem_list3_init(cachep->nodelists[node]); | |
1865 | } | |
1866 | } | |
1867 | } | |
1868 | cachep->nodelists[numa_node_id()]->next_reap = | |
1869 | jiffies + REAPTIMEOUT_LIST3 + | |
1870 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; | |
1871 | ||
1872 | cpu_cache_get(cachep)->avail = 0; | |
1873 | cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES; | |
1874 | cpu_cache_get(cachep)->batchcount = 1; | |
1875 | cpu_cache_get(cachep)->touched = 0; | |
1876 | cachep->batchcount = 1; | |
1877 | cachep->limit = BOOT_CPUCACHE_ENTRIES; | |
1878 | } | |
1879 | ||
1da177e4 LT |
1880 | /** |
1881 | * kmem_cache_create - Create a cache. | |
1882 | * @name: A string which is used in /proc/slabinfo to identify this cache. | |
1883 | * @size: The size of objects to be created in this cache. | |
1884 | * @align: The required alignment for the objects. | |
1885 | * @flags: SLAB flags | |
1886 | * @ctor: A constructor for the objects. | |
1887 | * @dtor: A destructor for the objects. | |
1888 | * | |
1889 | * Returns a ptr to the cache on success, NULL on failure. | |
1890 | * Cannot be called within a int, but can be interrupted. | |
1891 | * The @ctor is run when new pages are allocated by the cache | |
1892 | * and the @dtor is run before the pages are handed back. | |
1893 | * | |
1894 | * @name must be valid until the cache is destroyed. This implies that | |
a737b3e2 AM |
1895 | * the module calling this has to destroy the cache before getting unloaded. |
1896 | * | |
1da177e4 LT |
1897 | * The flags are |
1898 | * | |
1899 | * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5) | |
1900 | * to catch references to uninitialised memory. | |
1901 | * | |
1902 | * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check | |
1903 | * for buffer overruns. | |
1904 | * | |
1da177e4 LT |
1905 | * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware |
1906 | * cacheline. This can be beneficial if you're counting cycles as closely | |
1907 | * as davem. | |
1908 | */ | |
343e0d7a | 1909 | struct kmem_cache * |
1da177e4 | 1910 | kmem_cache_create (const char *name, size_t size, size_t align, |
a737b3e2 AM |
1911 | unsigned long flags, |
1912 | void (*ctor)(void*, struct kmem_cache *, unsigned long), | |
343e0d7a | 1913 | void (*dtor)(void*, struct kmem_cache *, unsigned long)) |
1da177e4 LT |
1914 | { |
1915 | size_t left_over, slab_size, ralign; | |
343e0d7a | 1916 | struct kmem_cache *cachep = NULL; |
4f12bb4f | 1917 | struct list_head *p; |
1da177e4 LT |
1918 | |
1919 | /* | |
1920 | * Sanity checks... these are all serious usage bugs. | |
1921 | */ | |
a737b3e2 | 1922 | if (!name || in_interrupt() || (size < BYTES_PER_WORD) || |
b28a02de | 1923 | (size > (1 << MAX_OBJ_ORDER) * PAGE_SIZE) || (dtor && !ctor)) { |
a737b3e2 AM |
1924 | printk(KERN_ERR "%s: Early error in slab %s\n", __FUNCTION__, |
1925 | name); | |
b28a02de PE |
1926 | BUG(); |
1927 | } | |
1da177e4 | 1928 | |
f0188f47 RT |
1929 | /* |
1930 | * Prevent CPUs from coming and going. | |
1931 | * lock_cpu_hotplug() nests outside cache_chain_mutex | |
1932 | */ | |
1933 | lock_cpu_hotplug(); | |
1934 | ||
fc0abb14 | 1935 | mutex_lock(&cache_chain_mutex); |
4f12bb4f AM |
1936 | |
1937 | list_for_each(p, &cache_chain) { | |
343e0d7a | 1938 | struct kmem_cache *pc = list_entry(p, struct kmem_cache, next); |
4f12bb4f AM |
1939 | mm_segment_t old_fs = get_fs(); |
1940 | char tmp; | |
1941 | int res; | |
1942 | ||
1943 | /* | |
1944 | * This happens when the module gets unloaded and doesn't | |
1945 | * destroy its slab cache and no-one else reuses the vmalloc | |
1946 | * area of the module. Print a warning. | |
1947 | */ | |
1948 | set_fs(KERNEL_DS); | |
1949 | res = __get_user(tmp, pc->name); | |
1950 | set_fs(old_fs); | |
1951 | if (res) { | |
1952 | printk("SLAB: cache with size %d has lost its name\n", | |
3dafccf2 | 1953 | pc->buffer_size); |
4f12bb4f AM |
1954 | continue; |
1955 | } | |
1956 | ||
b28a02de | 1957 | if (!strcmp(pc->name, name)) { |
4f12bb4f AM |
1958 | printk("kmem_cache_create: duplicate cache %s\n", name); |
1959 | dump_stack(); | |
1960 | goto oops; | |
1961 | } | |
1962 | } | |
1963 | ||
1da177e4 LT |
1964 | #if DEBUG |
1965 | WARN_ON(strchr(name, ' ')); /* It confuses parsers */ | |
1966 | if ((flags & SLAB_DEBUG_INITIAL) && !ctor) { | |
1967 | /* No constructor, but inital state check requested */ | |
1968 | printk(KERN_ERR "%s: No con, but init state check " | |
b28a02de | 1969 | "requested - %s\n", __FUNCTION__, name); |
1da177e4 LT |
1970 | flags &= ~SLAB_DEBUG_INITIAL; |
1971 | } | |
1da177e4 LT |
1972 | #if FORCED_DEBUG |
1973 | /* | |
1974 | * Enable redzoning and last user accounting, except for caches with | |
1975 | * large objects, if the increased size would increase the object size | |
1976 | * above the next power of two: caches with object sizes just above a | |
1977 | * power of two have a significant amount of internal fragmentation. | |
1978 | */ | |
a737b3e2 | 1979 | if (size < 4096 || fls(size - 1) == fls(size-1 + 3 * BYTES_PER_WORD)) |
b28a02de | 1980 | flags |= SLAB_RED_ZONE | SLAB_STORE_USER; |
1da177e4 LT |
1981 | if (!(flags & SLAB_DESTROY_BY_RCU)) |
1982 | flags |= SLAB_POISON; | |
1983 | #endif | |
1984 | if (flags & SLAB_DESTROY_BY_RCU) | |
1985 | BUG_ON(flags & SLAB_POISON); | |
1986 | #endif | |
1987 | if (flags & SLAB_DESTROY_BY_RCU) | |
1988 | BUG_ON(dtor); | |
1989 | ||
1990 | /* | |
a737b3e2 AM |
1991 | * Always checks flags, a caller might be expecting debug support which |
1992 | * isn't available. | |
1da177e4 | 1993 | */ |
40094fa6 | 1994 | BUG_ON(flags & ~CREATE_MASK); |
1da177e4 | 1995 | |
a737b3e2 AM |
1996 | /* |
1997 | * Check that size is in terms of words. This is needed to avoid | |
1da177e4 LT |
1998 | * unaligned accesses for some archs when redzoning is used, and makes |
1999 | * sure any on-slab bufctl's are also correctly aligned. | |
2000 | */ | |
b28a02de PE |
2001 | if (size & (BYTES_PER_WORD - 1)) { |
2002 | size += (BYTES_PER_WORD - 1); | |
2003 | size &= ~(BYTES_PER_WORD - 1); | |
1da177e4 LT |
2004 | } |
2005 | ||
a737b3e2 AM |
2006 | /* calculate the final buffer alignment: */ |
2007 | ||
1da177e4 LT |
2008 | /* 1) arch recommendation: can be overridden for debug */ |
2009 | if (flags & SLAB_HWCACHE_ALIGN) { | |
a737b3e2 AM |
2010 | /* |
2011 | * Default alignment: as specified by the arch code. Except if | |
2012 | * an object is really small, then squeeze multiple objects into | |
2013 | * one cacheline. | |
1da177e4 LT |
2014 | */ |
2015 | ralign = cache_line_size(); | |
b28a02de | 2016 | while (size <= ralign / 2) |
1da177e4 LT |
2017 | ralign /= 2; |
2018 | } else { | |
2019 | ralign = BYTES_PER_WORD; | |
2020 | } | |
2021 | /* 2) arch mandated alignment: disables debug if necessary */ | |
2022 | if (ralign < ARCH_SLAB_MINALIGN) { | |
2023 | ralign = ARCH_SLAB_MINALIGN; | |
2024 | if (ralign > BYTES_PER_WORD) | |
b28a02de | 2025 | flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
1da177e4 LT |
2026 | } |
2027 | /* 3) caller mandated alignment: disables debug if necessary */ | |
2028 | if (ralign < align) { | |
2029 | ralign = align; | |
2030 | if (ralign > BYTES_PER_WORD) | |
b28a02de | 2031 | flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
1da177e4 | 2032 | } |
a737b3e2 AM |
2033 | /* |
2034 | * 4) Store it. Note that the debug code below can reduce | |
1da177e4 LT |
2035 | * the alignment to BYTES_PER_WORD. |
2036 | */ | |
2037 | align = ralign; | |
2038 | ||
2039 | /* Get cache's description obj. */ | |
c5e3b83e | 2040 | cachep = kmem_cache_zalloc(&cache_cache, SLAB_KERNEL); |
1da177e4 | 2041 | if (!cachep) |
4f12bb4f | 2042 | goto oops; |
1da177e4 LT |
2043 | |
2044 | #if DEBUG | |
3dafccf2 | 2045 | cachep->obj_size = size; |
1da177e4 LT |
2046 | |
2047 | if (flags & SLAB_RED_ZONE) { | |
2048 | /* redzoning only works with word aligned caches */ | |
2049 | align = BYTES_PER_WORD; | |
2050 | ||
2051 | /* add space for red zone words */ | |
3dafccf2 | 2052 | cachep->obj_offset += BYTES_PER_WORD; |
b28a02de | 2053 | size += 2 * BYTES_PER_WORD; |
1da177e4 LT |
2054 | } |
2055 | if (flags & SLAB_STORE_USER) { | |
2056 | /* user store requires word alignment and | |
2057 | * one word storage behind the end of the real | |
2058 | * object. | |
2059 | */ | |
2060 | align = BYTES_PER_WORD; | |
2061 | size += BYTES_PER_WORD; | |
2062 | } | |
2063 | #if FORCED_DEBUG && defined(CONFIG_DEBUG_PAGEALLOC) | |
b28a02de | 2064 | if (size >= malloc_sizes[INDEX_L3 + 1].cs_size |
3dafccf2 MS |
2065 | && cachep->obj_size > cache_line_size() && size < PAGE_SIZE) { |
2066 | cachep->obj_offset += PAGE_SIZE - size; | |
1da177e4 LT |
2067 | size = PAGE_SIZE; |
2068 | } | |
2069 | #endif | |
2070 | #endif | |
2071 | ||
2072 | /* Determine if the slab management is 'on' or 'off' slab. */ | |
b28a02de | 2073 | if (size >= (PAGE_SIZE >> 3)) |
1da177e4 LT |
2074 | /* |
2075 | * Size is large, assume best to place the slab management obj | |
2076 | * off-slab (should allow better packing of objs). | |
2077 | */ | |
2078 | flags |= CFLGS_OFF_SLAB; | |
2079 | ||
2080 | size = ALIGN(size, align); | |
2081 | ||
f78bb8ad | 2082 | left_over = calculate_slab_order(cachep, size, align, flags); |
1da177e4 LT |
2083 | |
2084 | if (!cachep->num) { | |
2085 | printk("kmem_cache_create: couldn't create cache %s.\n", name); | |
2086 | kmem_cache_free(&cache_cache, cachep); | |
2087 | cachep = NULL; | |
4f12bb4f | 2088 | goto oops; |
1da177e4 | 2089 | } |
b28a02de PE |
2090 | slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t) |
2091 | + sizeof(struct slab), align); | |
1da177e4 LT |
2092 | |
2093 | /* | |
2094 | * If the slab has been placed off-slab, and we have enough space then | |
2095 | * move it on-slab. This is at the expense of any extra colouring. | |
2096 | */ | |
2097 | if (flags & CFLGS_OFF_SLAB && left_over >= slab_size) { | |
2098 | flags &= ~CFLGS_OFF_SLAB; | |
2099 | left_over -= slab_size; | |
2100 | } | |
2101 | ||
2102 | if (flags & CFLGS_OFF_SLAB) { | |
2103 | /* really off slab. No need for manual alignment */ | |
b28a02de PE |
2104 | slab_size = |
2105 | cachep->num * sizeof(kmem_bufctl_t) + sizeof(struct slab); | |
1da177e4 LT |
2106 | } |
2107 | ||
2108 | cachep->colour_off = cache_line_size(); | |
2109 | /* Offset must be a multiple of the alignment. */ | |
2110 | if (cachep->colour_off < align) | |
2111 | cachep->colour_off = align; | |
b28a02de | 2112 | cachep->colour = left_over / cachep->colour_off; |
1da177e4 LT |
2113 | cachep->slab_size = slab_size; |
2114 | cachep->flags = flags; | |
2115 | cachep->gfpflags = 0; | |
2116 | if (flags & SLAB_CACHE_DMA) | |
2117 | cachep->gfpflags |= GFP_DMA; | |
3dafccf2 | 2118 | cachep->buffer_size = size; |
1da177e4 LT |
2119 | |
2120 | if (flags & CFLGS_OFF_SLAB) | |
b2d55073 | 2121 | cachep->slabp_cache = kmem_find_general_cachep(slab_size, 0u); |
1da177e4 LT |
2122 | cachep->ctor = ctor; |
2123 | cachep->dtor = dtor; | |
2124 | cachep->name = name; | |
2125 | ||
1da177e4 | 2126 | |
f30cf7d1 | 2127 | setup_cpu_cache(cachep); |
1da177e4 | 2128 | |
1da177e4 LT |
2129 | /* cache setup completed, link it into the list */ |
2130 | list_add(&cachep->next, &cache_chain); | |
a737b3e2 | 2131 | oops: |
1da177e4 LT |
2132 | if (!cachep && (flags & SLAB_PANIC)) |
2133 | panic("kmem_cache_create(): failed to create slab `%s'\n", | |
b28a02de | 2134 | name); |
fc0abb14 | 2135 | mutex_unlock(&cache_chain_mutex); |
f0188f47 | 2136 | unlock_cpu_hotplug(); |
1da177e4 LT |
2137 | return cachep; |
2138 | } | |
2139 | EXPORT_SYMBOL(kmem_cache_create); | |
2140 | ||
2141 | #if DEBUG | |
2142 | static void check_irq_off(void) | |
2143 | { | |
2144 | BUG_ON(!irqs_disabled()); | |
2145 | } | |
2146 | ||
2147 | static void check_irq_on(void) | |
2148 | { | |
2149 | BUG_ON(irqs_disabled()); | |
2150 | } | |
2151 | ||
343e0d7a | 2152 | static void check_spinlock_acquired(struct kmem_cache *cachep) |
1da177e4 LT |
2153 | { |
2154 | #ifdef CONFIG_SMP | |
2155 | check_irq_off(); | |
e498be7d | 2156 | assert_spin_locked(&cachep->nodelists[numa_node_id()]->list_lock); |
1da177e4 LT |
2157 | #endif |
2158 | } | |
e498be7d | 2159 | |
343e0d7a | 2160 | static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) |
e498be7d CL |
2161 | { |
2162 | #ifdef CONFIG_SMP | |
2163 | check_irq_off(); | |
2164 | assert_spin_locked(&cachep->nodelists[node]->list_lock); | |
2165 | #endif | |
2166 | } | |
2167 | ||
1da177e4 LT |
2168 | #else |
2169 | #define check_irq_off() do { } while(0) | |
2170 | #define check_irq_on() do { } while(0) | |
2171 | #define check_spinlock_acquired(x) do { } while(0) | |
e498be7d | 2172 | #define check_spinlock_acquired_node(x, y) do { } while(0) |
1da177e4 LT |
2173 | #endif |
2174 | ||
aab2207c CL |
2175 | static void drain_array(struct kmem_cache *cachep, struct kmem_list3 *l3, |
2176 | struct array_cache *ac, | |
2177 | int force, int node); | |
2178 | ||
1da177e4 LT |
2179 | static void do_drain(void *arg) |
2180 | { | |
a737b3e2 | 2181 | struct kmem_cache *cachep = arg; |
1da177e4 | 2182 | struct array_cache *ac; |
ff69416e | 2183 | int node = numa_node_id(); |
1da177e4 LT |
2184 | |
2185 | check_irq_off(); | |
9a2dba4b | 2186 | ac = cpu_cache_get(cachep); |
ff69416e CL |
2187 | spin_lock(&cachep->nodelists[node]->list_lock); |
2188 | free_block(cachep, ac->entry, ac->avail, node); | |
2189 | spin_unlock(&cachep->nodelists[node]->list_lock); | |
1da177e4 LT |
2190 | ac->avail = 0; |
2191 | } | |
2192 | ||
343e0d7a | 2193 | static void drain_cpu_caches(struct kmem_cache *cachep) |
1da177e4 | 2194 | { |
e498be7d CL |
2195 | struct kmem_list3 *l3; |
2196 | int node; | |
2197 | ||
a07fa394 | 2198 | on_each_cpu(do_drain, cachep, 1, 1); |
1da177e4 | 2199 | check_irq_on(); |
b28a02de | 2200 | for_each_online_node(node) { |
e498be7d | 2201 | l3 = cachep->nodelists[node]; |
a4523a8b RD |
2202 | if (l3 && l3->alien) |
2203 | drain_alien_cache(cachep, l3->alien); | |
2204 | } | |
2205 | ||
2206 | for_each_online_node(node) { | |
2207 | l3 = cachep->nodelists[node]; | |
2208 | if (l3) | |
aab2207c | 2209 | drain_array(cachep, l3, l3->shared, 1, node); |
e498be7d | 2210 | } |
1da177e4 LT |
2211 | } |
2212 | ||
343e0d7a | 2213 | static int __node_shrink(struct kmem_cache *cachep, int node) |
1da177e4 LT |
2214 | { |
2215 | struct slab *slabp; | |
e498be7d | 2216 | struct kmem_list3 *l3 = cachep->nodelists[node]; |
1da177e4 LT |
2217 | int ret; |
2218 | ||
e498be7d | 2219 | for (;;) { |
1da177e4 LT |
2220 | struct list_head *p; |
2221 | ||
e498be7d CL |
2222 | p = l3->slabs_free.prev; |
2223 | if (p == &l3->slabs_free) | |
1da177e4 LT |
2224 | break; |
2225 | ||
e498be7d | 2226 | slabp = list_entry(l3->slabs_free.prev, struct slab, list); |
1da177e4 | 2227 | #if DEBUG |
40094fa6 | 2228 | BUG_ON(slabp->inuse); |
1da177e4 LT |
2229 | #endif |
2230 | list_del(&slabp->list); | |
2231 | ||
e498be7d CL |
2232 | l3->free_objects -= cachep->num; |
2233 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 2234 | slab_destroy(cachep, slabp); |
e498be7d | 2235 | spin_lock_irq(&l3->list_lock); |
1da177e4 | 2236 | } |
b28a02de | 2237 | ret = !list_empty(&l3->slabs_full) || !list_empty(&l3->slabs_partial); |
1da177e4 LT |
2238 | return ret; |
2239 | } | |
2240 | ||
343e0d7a | 2241 | static int __cache_shrink(struct kmem_cache *cachep) |
e498be7d CL |
2242 | { |
2243 | int ret = 0, i = 0; | |
2244 | struct kmem_list3 *l3; | |
2245 | ||
2246 | drain_cpu_caches(cachep); | |
2247 | ||
2248 | check_irq_on(); | |
2249 | for_each_online_node(i) { | |
2250 | l3 = cachep->nodelists[i]; | |
2251 | if (l3) { | |
2252 | spin_lock_irq(&l3->list_lock); | |
2253 | ret += __node_shrink(cachep, i); | |
2254 | spin_unlock_irq(&l3->list_lock); | |
2255 | } | |
2256 | } | |
2257 | return (ret ? 1 : 0); | |
2258 | } | |
2259 | ||
1da177e4 LT |
2260 | /** |
2261 | * kmem_cache_shrink - Shrink a cache. | |
2262 | * @cachep: The cache to shrink. | |
2263 | * | |
2264 | * Releases as many slabs as possible for a cache. | |
2265 | * To help debugging, a zero exit status indicates all slabs were released. | |
2266 | */ | |
343e0d7a | 2267 | int kmem_cache_shrink(struct kmem_cache *cachep) |
1da177e4 | 2268 | { |
40094fa6 | 2269 | BUG_ON(!cachep || in_interrupt()); |
1da177e4 LT |
2270 | |
2271 | return __cache_shrink(cachep); | |
2272 | } | |
2273 | EXPORT_SYMBOL(kmem_cache_shrink); | |
2274 | ||
2275 | /** | |
2276 | * kmem_cache_destroy - delete a cache | |
2277 | * @cachep: the cache to destroy | |
2278 | * | |
343e0d7a | 2279 | * Remove a struct kmem_cache object from the slab cache. |
1da177e4 LT |
2280 | * Returns 0 on success. |
2281 | * | |
2282 | * It is expected this function will be called by a module when it is | |
2283 | * unloaded. This will remove the cache completely, and avoid a duplicate | |
2284 | * cache being allocated each time a module is loaded and unloaded, if the | |
2285 | * module doesn't have persistent in-kernel storage across loads and unloads. | |
2286 | * | |
2287 | * The cache must be empty before calling this function. | |
2288 | * | |
2289 | * The caller must guarantee that noone will allocate memory from the cache | |
2290 | * during the kmem_cache_destroy(). | |
2291 | */ | |
343e0d7a | 2292 | int kmem_cache_destroy(struct kmem_cache *cachep) |
1da177e4 LT |
2293 | { |
2294 | int i; | |
e498be7d | 2295 | struct kmem_list3 *l3; |
1da177e4 | 2296 | |
40094fa6 | 2297 | BUG_ON(!cachep || in_interrupt()); |
1da177e4 LT |
2298 | |
2299 | /* Don't let CPUs to come and go */ | |
2300 | lock_cpu_hotplug(); | |
2301 | ||
2302 | /* Find the cache in the chain of caches. */ | |
fc0abb14 | 2303 | mutex_lock(&cache_chain_mutex); |
1da177e4 LT |
2304 | /* |
2305 | * the chain is never empty, cache_cache is never destroyed | |
2306 | */ | |
2307 | list_del(&cachep->next); | |
fc0abb14 | 2308 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
2309 | |
2310 | if (__cache_shrink(cachep)) { | |
2311 | slab_error(cachep, "Can't free all objects"); | |
fc0abb14 | 2312 | mutex_lock(&cache_chain_mutex); |
b28a02de | 2313 | list_add(&cachep->next, &cache_chain); |
fc0abb14 | 2314 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
2315 | unlock_cpu_hotplug(); |
2316 | return 1; | |
2317 | } | |
2318 | ||
2319 | if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) | |
fbd568a3 | 2320 | synchronize_rcu(); |
1da177e4 | 2321 | |
e498be7d | 2322 | for_each_online_cpu(i) |
b28a02de | 2323 | kfree(cachep->array[i]); |
1da177e4 LT |
2324 | |
2325 | /* NUMA: free the list3 structures */ | |
e498be7d | 2326 | for_each_online_node(i) { |
a737b3e2 AM |
2327 | l3 = cachep->nodelists[i]; |
2328 | if (l3) { | |
e498be7d CL |
2329 | kfree(l3->shared); |
2330 | free_alien_cache(l3->alien); | |
2331 | kfree(l3); | |
2332 | } | |
2333 | } | |
1da177e4 | 2334 | kmem_cache_free(&cache_cache, cachep); |
1da177e4 | 2335 | unlock_cpu_hotplug(); |
1da177e4 LT |
2336 | return 0; |
2337 | } | |
2338 | EXPORT_SYMBOL(kmem_cache_destroy); | |
2339 | ||
2340 | /* Get the memory for a slab management obj. */ | |
343e0d7a | 2341 | static struct slab *alloc_slabmgmt(struct kmem_cache *cachep, void *objp, |
5b74ada7 RT |
2342 | int colour_off, gfp_t local_flags, |
2343 | int nodeid) | |
1da177e4 LT |
2344 | { |
2345 | struct slab *slabp; | |
b28a02de | 2346 | |
1da177e4 LT |
2347 | if (OFF_SLAB(cachep)) { |
2348 | /* Slab management obj is off-slab. */ | |
5b74ada7 RT |
2349 | slabp = kmem_cache_alloc_node(cachep->slabp_cache, |
2350 | local_flags, nodeid); | |
1da177e4 LT |
2351 | if (!slabp) |
2352 | return NULL; | |
2353 | } else { | |
b28a02de | 2354 | slabp = objp + colour_off; |
1da177e4 LT |
2355 | colour_off += cachep->slab_size; |
2356 | } | |
2357 | slabp->inuse = 0; | |
2358 | slabp->colouroff = colour_off; | |
b28a02de | 2359 | slabp->s_mem = objp + colour_off; |
5b74ada7 | 2360 | slabp->nodeid = nodeid; |
1da177e4 LT |
2361 | return slabp; |
2362 | } | |
2363 | ||
2364 | static inline kmem_bufctl_t *slab_bufctl(struct slab *slabp) | |
2365 | { | |
b28a02de | 2366 | return (kmem_bufctl_t *) (slabp + 1); |
1da177e4 LT |
2367 | } |
2368 | ||
343e0d7a | 2369 | static void cache_init_objs(struct kmem_cache *cachep, |
b28a02de | 2370 | struct slab *slabp, unsigned long ctor_flags) |
1da177e4 LT |
2371 | { |
2372 | int i; | |
2373 | ||
2374 | for (i = 0; i < cachep->num; i++) { | |
8fea4e96 | 2375 | void *objp = index_to_obj(cachep, slabp, i); |
1da177e4 LT |
2376 | #if DEBUG |
2377 | /* need to poison the objs? */ | |
2378 | if (cachep->flags & SLAB_POISON) | |
2379 | poison_obj(cachep, objp, POISON_FREE); | |
2380 | if (cachep->flags & SLAB_STORE_USER) | |
2381 | *dbg_userword(cachep, objp) = NULL; | |
2382 | ||
2383 | if (cachep->flags & SLAB_RED_ZONE) { | |
2384 | *dbg_redzone1(cachep, objp) = RED_INACTIVE; | |
2385 | *dbg_redzone2(cachep, objp) = RED_INACTIVE; | |
2386 | } | |
2387 | /* | |
a737b3e2 AM |
2388 | * Constructors are not allowed to allocate memory from the same |
2389 | * cache which they are a constructor for. Otherwise, deadlock. | |
2390 | * They must also be threaded. | |
1da177e4 LT |
2391 | */ |
2392 | if (cachep->ctor && !(cachep->flags & SLAB_POISON)) | |
3dafccf2 | 2393 | cachep->ctor(objp + obj_offset(cachep), cachep, |
b28a02de | 2394 | ctor_flags); |
1da177e4 LT |
2395 | |
2396 | if (cachep->flags & SLAB_RED_ZONE) { | |
2397 | if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) | |
2398 | slab_error(cachep, "constructor overwrote the" | |
b28a02de | 2399 | " end of an object"); |
1da177e4 LT |
2400 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) |
2401 | slab_error(cachep, "constructor overwrote the" | |
b28a02de | 2402 | " start of an object"); |
1da177e4 | 2403 | } |
a737b3e2 AM |
2404 | if ((cachep->buffer_size % PAGE_SIZE) == 0 && |
2405 | OFF_SLAB(cachep) && cachep->flags & SLAB_POISON) | |
b28a02de | 2406 | kernel_map_pages(virt_to_page(objp), |
3dafccf2 | 2407 | cachep->buffer_size / PAGE_SIZE, 0); |
1da177e4 LT |
2408 | #else |
2409 | if (cachep->ctor) | |
2410 | cachep->ctor(objp, cachep, ctor_flags); | |
2411 | #endif | |
b28a02de | 2412 | slab_bufctl(slabp)[i] = i + 1; |
1da177e4 | 2413 | } |
b28a02de | 2414 | slab_bufctl(slabp)[i - 1] = BUFCTL_END; |
1da177e4 LT |
2415 | slabp->free = 0; |
2416 | } | |
2417 | ||
343e0d7a | 2418 | static void kmem_flagcheck(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 | 2419 | { |
a737b3e2 AM |
2420 | if (flags & SLAB_DMA) |
2421 | BUG_ON(!(cachep->gfpflags & GFP_DMA)); | |
2422 | else | |
2423 | BUG_ON(cachep->gfpflags & GFP_DMA); | |
1da177e4 LT |
2424 | } |
2425 | ||
a737b3e2 AM |
2426 | static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp, |
2427 | int nodeid) | |
78d382d7 | 2428 | { |
8fea4e96 | 2429 | void *objp = index_to_obj(cachep, slabp, slabp->free); |
78d382d7 MD |
2430 | kmem_bufctl_t next; |
2431 | ||
2432 | slabp->inuse++; | |
2433 | next = slab_bufctl(slabp)[slabp->free]; | |
2434 | #if DEBUG | |
2435 | slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE; | |
2436 | WARN_ON(slabp->nodeid != nodeid); | |
2437 | #endif | |
2438 | slabp->free = next; | |
2439 | ||
2440 | return objp; | |
2441 | } | |
2442 | ||
a737b3e2 AM |
2443 | static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp, |
2444 | void *objp, int nodeid) | |
78d382d7 | 2445 | { |
8fea4e96 | 2446 | unsigned int objnr = obj_to_index(cachep, slabp, objp); |
78d382d7 MD |
2447 | |
2448 | #if DEBUG | |
2449 | /* Verify that the slab belongs to the intended node */ | |
2450 | WARN_ON(slabp->nodeid != nodeid); | |
2451 | ||
871751e2 | 2452 | if (slab_bufctl(slabp)[objnr] + 1 <= SLAB_LIMIT + 1) { |
78d382d7 | 2453 | printk(KERN_ERR "slab: double free detected in cache " |
a737b3e2 | 2454 | "'%s', objp %p\n", cachep->name, objp); |
78d382d7 MD |
2455 | BUG(); |
2456 | } | |
2457 | #endif | |
2458 | slab_bufctl(slabp)[objnr] = slabp->free; | |
2459 | slabp->free = objnr; | |
2460 | slabp->inuse--; | |
2461 | } | |
2462 | ||
a737b3e2 AM |
2463 | static void set_slab_attr(struct kmem_cache *cachep, struct slab *slabp, |
2464 | void *objp) | |
1da177e4 LT |
2465 | { |
2466 | int i; | |
2467 | struct page *page; | |
2468 | ||
2469 | /* Nasty!!!!!! I hope this is OK. */ | |
1da177e4 | 2470 | page = virt_to_page(objp); |
84097518 NP |
2471 | |
2472 | i = 1; | |
2473 | if (likely(!PageCompound(page))) | |
2474 | i <<= cachep->gfporder; | |
1da177e4 | 2475 | do { |
065d41cb PE |
2476 | page_set_cache(page, cachep); |
2477 | page_set_slab(page, slabp); | |
1da177e4 LT |
2478 | page++; |
2479 | } while (--i); | |
2480 | } | |
2481 | ||
2482 | /* | |
2483 | * Grow (by 1) the number of slabs within a cache. This is called by | |
2484 | * kmem_cache_alloc() when there are no active objs left in a cache. | |
2485 | */ | |
343e0d7a | 2486 | static int cache_grow(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 | 2487 | { |
b28a02de PE |
2488 | struct slab *slabp; |
2489 | void *objp; | |
2490 | size_t offset; | |
2491 | gfp_t local_flags; | |
2492 | unsigned long ctor_flags; | |
e498be7d | 2493 | struct kmem_list3 *l3; |
1da177e4 | 2494 | |
a737b3e2 AM |
2495 | /* |
2496 | * Be lazy and only check for valid flags here, keeping it out of the | |
2497 | * critical path in kmem_cache_alloc(). | |
1da177e4 | 2498 | */ |
40094fa6 | 2499 | BUG_ON(flags & ~(SLAB_DMA | SLAB_LEVEL_MASK | SLAB_NO_GROW)); |
1da177e4 LT |
2500 | if (flags & SLAB_NO_GROW) |
2501 | return 0; | |
2502 | ||
2503 | ctor_flags = SLAB_CTOR_CONSTRUCTOR; | |
2504 | local_flags = (flags & SLAB_LEVEL_MASK); | |
2505 | if (!(local_flags & __GFP_WAIT)) | |
2506 | /* | |
2507 | * Not allowed to sleep. Need to tell a constructor about | |
2508 | * this - it might need to know... | |
2509 | */ | |
2510 | ctor_flags |= SLAB_CTOR_ATOMIC; | |
2511 | ||
2e1217cf | 2512 | /* Take the l3 list lock to change the colour_next on this node */ |
1da177e4 | 2513 | check_irq_off(); |
2e1217cf RT |
2514 | l3 = cachep->nodelists[nodeid]; |
2515 | spin_lock(&l3->list_lock); | |
1da177e4 LT |
2516 | |
2517 | /* Get colour for the slab, and cal the next value. */ | |
2e1217cf RT |
2518 | offset = l3->colour_next; |
2519 | l3->colour_next++; | |
2520 | if (l3->colour_next >= cachep->colour) | |
2521 | l3->colour_next = 0; | |
2522 | spin_unlock(&l3->list_lock); | |
1da177e4 | 2523 | |
2e1217cf | 2524 | offset *= cachep->colour_off; |
1da177e4 LT |
2525 | |
2526 | if (local_flags & __GFP_WAIT) | |
2527 | local_irq_enable(); | |
2528 | ||
2529 | /* | |
2530 | * The test for missing atomic flag is performed here, rather than | |
2531 | * the more obvious place, simply to reduce the critical path length | |
2532 | * in kmem_cache_alloc(). If a caller is seriously mis-behaving they | |
2533 | * will eventually be caught here (where it matters). | |
2534 | */ | |
2535 | kmem_flagcheck(cachep, flags); | |
2536 | ||
a737b3e2 AM |
2537 | /* |
2538 | * Get mem for the objs. Attempt to allocate a physical page from | |
2539 | * 'nodeid'. | |
e498be7d | 2540 | */ |
a737b3e2 AM |
2541 | objp = kmem_getpages(cachep, flags, nodeid); |
2542 | if (!objp) | |
1da177e4 LT |
2543 | goto failed; |
2544 | ||
2545 | /* Get slab management. */ | |
5b74ada7 | 2546 | slabp = alloc_slabmgmt(cachep, objp, offset, local_flags, nodeid); |
a737b3e2 | 2547 | if (!slabp) |
1da177e4 LT |
2548 | goto opps1; |
2549 | ||
e498be7d | 2550 | slabp->nodeid = nodeid; |
1da177e4 LT |
2551 | set_slab_attr(cachep, slabp, objp); |
2552 | ||
2553 | cache_init_objs(cachep, slabp, ctor_flags); | |
2554 | ||
2555 | if (local_flags & __GFP_WAIT) | |
2556 | local_irq_disable(); | |
2557 | check_irq_off(); | |
e498be7d | 2558 | spin_lock(&l3->list_lock); |
1da177e4 LT |
2559 | |
2560 | /* Make slab active. */ | |
e498be7d | 2561 | list_add_tail(&slabp->list, &(l3->slabs_free)); |
1da177e4 | 2562 | STATS_INC_GROWN(cachep); |
e498be7d CL |
2563 | l3->free_objects += cachep->num; |
2564 | spin_unlock(&l3->list_lock); | |
1da177e4 | 2565 | return 1; |
a737b3e2 | 2566 | opps1: |
1da177e4 | 2567 | kmem_freepages(cachep, objp); |
a737b3e2 | 2568 | failed: |
1da177e4 LT |
2569 | if (local_flags & __GFP_WAIT) |
2570 | local_irq_disable(); | |
2571 | return 0; | |
2572 | } | |
2573 | ||
2574 | #if DEBUG | |
2575 | ||
2576 | /* | |
2577 | * Perform extra freeing checks: | |
2578 | * - detect bad pointers. | |
2579 | * - POISON/RED_ZONE checking | |
2580 | * - destructor calls, for caches with POISON+dtor | |
2581 | */ | |
2582 | static void kfree_debugcheck(const void *objp) | |
2583 | { | |
2584 | struct page *page; | |
2585 | ||
2586 | if (!virt_addr_valid(objp)) { | |
2587 | printk(KERN_ERR "kfree_debugcheck: out of range ptr %lxh.\n", | |
b28a02de PE |
2588 | (unsigned long)objp); |
2589 | BUG(); | |
1da177e4 LT |
2590 | } |
2591 | page = virt_to_page(objp); | |
2592 | if (!PageSlab(page)) { | |
b28a02de PE |
2593 | printk(KERN_ERR "kfree_debugcheck: bad ptr %lxh.\n", |
2594 | (unsigned long)objp); | |
1da177e4 LT |
2595 | BUG(); |
2596 | } | |
2597 | } | |
2598 | ||
343e0d7a | 2599 | static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp, |
b28a02de | 2600 | void *caller) |
1da177e4 LT |
2601 | { |
2602 | struct page *page; | |
2603 | unsigned int objnr; | |
2604 | struct slab *slabp; | |
2605 | ||
3dafccf2 | 2606 | objp -= obj_offset(cachep); |
1da177e4 LT |
2607 | kfree_debugcheck(objp); |
2608 | page = virt_to_page(objp); | |
2609 | ||
065d41cb | 2610 | if (page_get_cache(page) != cachep) { |
a737b3e2 AM |
2611 | printk(KERN_ERR "mismatch in kmem_cache_free: expected " |
2612 | "cache %p, got %p\n", | |
b28a02de | 2613 | page_get_cache(page), cachep); |
1da177e4 | 2614 | printk(KERN_ERR "%p is %s.\n", cachep, cachep->name); |
b28a02de PE |
2615 | printk(KERN_ERR "%p is %s.\n", page_get_cache(page), |
2616 | page_get_cache(page)->name); | |
1da177e4 LT |
2617 | WARN_ON(1); |
2618 | } | |
065d41cb | 2619 | slabp = page_get_slab(page); |
1da177e4 LT |
2620 | |
2621 | if (cachep->flags & SLAB_RED_ZONE) { | |
a737b3e2 AM |
2622 | if (*dbg_redzone1(cachep, objp) != RED_ACTIVE || |
2623 | *dbg_redzone2(cachep, objp) != RED_ACTIVE) { | |
2624 | slab_error(cachep, "double free, or memory outside" | |
2625 | " object was overwritten"); | |
2626 | printk(KERN_ERR "%p: redzone 1:0x%lx, " | |
2627 | "redzone 2:0x%lx.\n", | |
b28a02de PE |
2628 | objp, *dbg_redzone1(cachep, objp), |
2629 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
2630 | } |
2631 | *dbg_redzone1(cachep, objp) = RED_INACTIVE; | |
2632 | *dbg_redzone2(cachep, objp) = RED_INACTIVE; | |
2633 | } | |
2634 | if (cachep->flags & SLAB_STORE_USER) | |
2635 | *dbg_userword(cachep, objp) = caller; | |
2636 | ||
8fea4e96 | 2637 | objnr = obj_to_index(cachep, slabp, objp); |
1da177e4 LT |
2638 | |
2639 | BUG_ON(objnr >= cachep->num); | |
8fea4e96 | 2640 | BUG_ON(objp != index_to_obj(cachep, slabp, objnr)); |
1da177e4 LT |
2641 | |
2642 | if (cachep->flags & SLAB_DEBUG_INITIAL) { | |
a737b3e2 AM |
2643 | /* |
2644 | * Need to call the slab's constructor so the caller can | |
2645 | * perform a verify of its state (debugging). Called without | |
2646 | * the cache-lock held. | |
1da177e4 | 2647 | */ |
3dafccf2 | 2648 | cachep->ctor(objp + obj_offset(cachep), |
b28a02de | 2649 | cachep, SLAB_CTOR_CONSTRUCTOR | SLAB_CTOR_VERIFY); |
1da177e4 LT |
2650 | } |
2651 | if (cachep->flags & SLAB_POISON && cachep->dtor) { | |
2652 | /* we want to cache poison the object, | |
2653 | * call the destruction callback | |
2654 | */ | |
3dafccf2 | 2655 | cachep->dtor(objp + obj_offset(cachep), cachep, 0); |
1da177e4 | 2656 | } |
871751e2 AV |
2657 | #ifdef CONFIG_DEBUG_SLAB_LEAK |
2658 | slab_bufctl(slabp)[objnr] = BUFCTL_FREE; | |
2659 | #endif | |
1da177e4 LT |
2660 | if (cachep->flags & SLAB_POISON) { |
2661 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
a737b3e2 | 2662 | if ((cachep->buffer_size % PAGE_SIZE)==0 && OFF_SLAB(cachep)) { |
1da177e4 | 2663 | store_stackinfo(cachep, objp, (unsigned long)caller); |
b28a02de | 2664 | kernel_map_pages(virt_to_page(objp), |
3dafccf2 | 2665 | cachep->buffer_size / PAGE_SIZE, 0); |
1da177e4 LT |
2666 | } else { |
2667 | poison_obj(cachep, objp, POISON_FREE); | |
2668 | } | |
2669 | #else | |
2670 | poison_obj(cachep, objp, POISON_FREE); | |
2671 | #endif | |
2672 | } | |
2673 | return objp; | |
2674 | } | |
2675 | ||
343e0d7a | 2676 | static void check_slabp(struct kmem_cache *cachep, struct slab *slabp) |
1da177e4 LT |
2677 | { |
2678 | kmem_bufctl_t i; | |
2679 | int entries = 0; | |
b28a02de | 2680 | |
1da177e4 LT |
2681 | /* Check slab's freelist to see if this obj is there. */ |
2682 | for (i = slabp->free; i != BUFCTL_END; i = slab_bufctl(slabp)[i]) { | |
2683 | entries++; | |
2684 | if (entries > cachep->num || i >= cachep->num) | |
2685 | goto bad; | |
2686 | } | |
2687 | if (entries != cachep->num - slabp->inuse) { | |
a737b3e2 AM |
2688 | bad: |
2689 | printk(KERN_ERR "slab: Internal list corruption detected in " | |
2690 | "cache '%s'(%d), slabp %p(%d). Hexdump:\n", | |
2691 | cachep->name, cachep->num, slabp, slabp->inuse); | |
b28a02de | 2692 | for (i = 0; |
264132bc | 2693 | i < sizeof(*slabp) + cachep->num * sizeof(kmem_bufctl_t); |
b28a02de | 2694 | i++) { |
a737b3e2 | 2695 | if (i % 16 == 0) |
1da177e4 | 2696 | printk("\n%03x:", i); |
b28a02de | 2697 | printk(" %02x", ((unsigned char *)slabp)[i]); |
1da177e4 LT |
2698 | } |
2699 | printk("\n"); | |
2700 | BUG(); | |
2701 | } | |
2702 | } | |
2703 | #else | |
2704 | #define kfree_debugcheck(x) do { } while(0) | |
2705 | #define cache_free_debugcheck(x,objp,z) (objp) | |
2706 | #define check_slabp(x,y) do { } while(0) | |
2707 | #endif | |
2708 | ||
343e0d7a | 2709 | static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 LT |
2710 | { |
2711 | int batchcount; | |
2712 | struct kmem_list3 *l3; | |
2713 | struct array_cache *ac; | |
2714 | ||
2715 | check_irq_off(); | |
9a2dba4b | 2716 | ac = cpu_cache_get(cachep); |
a737b3e2 | 2717 | retry: |
1da177e4 LT |
2718 | batchcount = ac->batchcount; |
2719 | if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { | |
a737b3e2 AM |
2720 | /* |
2721 | * If there was little recent activity on this cache, then | |
2722 | * perform only a partial refill. Otherwise we could generate | |
2723 | * refill bouncing. | |
1da177e4 LT |
2724 | */ |
2725 | batchcount = BATCHREFILL_LIMIT; | |
2726 | } | |
e498be7d CL |
2727 | l3 = cachep->nodelists[numa_node_id()]; |
2728 | ||
2729 | BUG_ON(ac->avail > 0 || !l3); | |
2730 | spin_lock(&l3->list_lock); | |
1da177e4 | 2731 | |
3ded175a CL |
2732 | /* See if we can refill from the shared array */ |
2733 | if (l3->shared && transfer_objects(ac, l3->shared, batchcount)) | |
2734 | goto alloc_done; | |
2735 | ||
1da177e4 LT |
2736 | while (batchcount > 0) { |
2737 | struct list_head *entry; | |
2738 | struct slab *slabp; | |
2739 | /* Get slab alloc is to come from. */ | |
2740 | entry = l3->slabs_partial.next; | |
2741 | if (entry == &l3->slabs_partial) { | |
2742 | l3->free_touched = 1; | |
2743 | entry = l3->slabs_free.next; | |
2744 | if (entry == &l3->slabs_free) | |
2745 | goto must_grow; | |
2746 | } | |
2747 | ||
2748 | slabp = list_entry(entry, struct slab, list); | |
2749 | check_slabp(cachep, slabp); | |
2750 | check_spinlock_acquired(cachep); | |
2751 | while (slabp->inuse < cachep->num && batchcount--) { | |
1da177e4 LT |
2752 | STATS_INC_ALLOCED(cachep); |
2753 | STATS_INC_ACTIVE(cachep); | |
2754 | STATS_SET_HIGH(cachep); | |
2755 | ||
78d382d7 MD |
2756 | ac->entry[ac->avail++] = slab_get_obj(cachep, slabp, |
2757 | numa_node_id()); | |
1da177e4 LT |
2758 | } |
2759 | check_slabp(cachep, slabp); | |
2760 | ||
2761 | /* move slabp to correct slabp list: */ | |
2762 | list_del(&slabp->list); | |
2763 | if (slabp->free == BUFCTL_END) | |
2764 | list_add(&slabp->list, &l3->slabs_full); | |
2765 | else | |
2766 | list_add(&slabp->list, &l3->slabs_partial); | |
2767 | } | |
2768 | ||
a737b3e2 | 2769 | must_grow: |
1da177e4 | 2770 | l3->free_objects -= ac->avail; |
a737b3e2 | 2771 | alloc_done: |
e498be7d | 2772 | spin_unlock(&l3->list_lock); |
1da177e4 LT |
2773 | |
2774 | if (unlikely(!ac->avail)) { | |
2775 | int x; | |
e498be7d CL |
2776 | x = cache_grow(cachep, flags, numa_node_id()); |
2777 | ||
a737b3e2 | 2778 | /* cache_grow can reenable interrupts, then ac could change. */ |
9a2dba4b | 2779 | ac = cpu_cache_get(cachep); |
a737b3e2 | 2780 | if (!x && ac->avail == 0) /* no objects in sight? abort */ |
1da177e4 LT |
2781 | return NULL; |
2782 | ||
a737b3e2 | 2783 | if (!ac->avail) /* objects refilled by interrupt? */ |
1da177e4 LT |
2784 | goto retry; |
2785 | } | |
2786 | ac->touched = 1; | |
e498be7d | 2787 | return ac->entry[--ac->avail]; |
1da177e4 LT |
2788 | } |
2789 | ||
a737b3e2 AM |
2790 | static inline void cache_alloc_debugcheck_before(struct kmem_cache *cachep, |
2791 | gfp_t flags) | |
1da177e4 LT |
2792 | { |
2793 | might_sleep_if(flags & __GFP_WAIT); | |
2794 | #if DEBUG | |
2795 | kmem_flagcheck(cachep, flags); | |
2796 | #endif | |
2797 | } | |
2798 | ||
2799 | #if DEBUG | |
a737b3e2 AM |
2800 | static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, |
2801 | gfp_t flags, void *objp, void *caller) | |
1da177e4 | 2802 | { |
b28a02de | 2803 | if (!objp) |
1da177e4 | 2804 | return objp; |
b28a02de | 2805 | if (cachep->flags & SLAB_POISON) { |
1da177e4 | 2806 | #ifdef CONFIG_DEBUG_PAGEALLOC |
3dafccf2 | 2807 | if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) |
b28a02de | 2808 | kernel_map_pages(virt_to_page(objp), |
3dafccf2 | 2809 | cachep->buffer_size / PAGE_SIZE, 1); |
1da177e4 LT |
2810 | else |
2811 | check_poison_obj(cachep, objp); | |
2812 | #else | |
2813 | check_poison_obj(cachep, objp); | |
2814 | #endif | |
2815 | poison_obj(cachep, objp, POISON_INUSE); | |
2816 | } | |
2817 | if (cachep->flags & SLAB_STORE_USER) | |
2818 | *dbg_userword(cachep, objp) = caller; | |
2819 | ||
2820 | if (cachep->flags & SLAB_RED_ZONE) { | |
a737b3e2 AM |
2821 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE || |
2822 | *dbg_redzone2(cachep, objp) != RED_INACTIVE) { | |
2823 | slab_error(cachep, "double free, or memory outside" | |
2824 | " object was overwritten"); | |
b28a02de | 2825 | printk(KERN_ERR |
a737b3e2 AM |
2826 | "%p: redzone 1:0x%lx, redzone 2:0x%lx\n", |
2827 | objp, *dbg_redzone1(cachep, objp), | |
2828 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
2829 | } |
2830 | *dbg_redzone1(cachep, objp) = RED_ACTIVE; | |
2831 | *dbg_redzone2(cachep, objp) = RED_ACTIVE; | |
2832 | } | |
871751e2 AV |
2833 | #ifdef CONFIG_DEBUG_SLAB_LEAK |
2834 | { | |
2835 | struct slab *slabp; | |
2836 | unsigned objnr; | |
2837 | ||
2838 | slabp = page_get_slab(virt_to_page(objp)); | |
2839 | objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size; | |
2840 | slab_bufctl(slabp)[objnr] = BUFCTL_ACTIVE; | |
2841 | } | |
2842 | #endif | |
3dafccf2 | 2843 | objp += obj_offset(cachep); |
1da177e4 | 2844 | if (cachep->ctor && cachep->flags & SLAB_POISON) { |
b28a02de | 2845 | unsigned long ctor_flags = SLAB_CTOR_CONSTRUCTOR; |
1da177e4 LT |
2846 | |
2847 | if (!(flags & __GFP_WAIT)) | |
2848 | ctor_flags |= SLAB_CTOR_ATOMIC; | |
2849 | ||
2850 | cachep->ctor(objp, cachep, ctor_flags); | |
b28a02de | 2851 | } |
1da177e4 LT |
2852 | return objp; |
2853 | } | |
2854 | #else | |
2855 | #define cache_alloc_debugcheck_after(a,b,objp,d) (objp) | |
2856 | #endif | |
2857 | ||
343e0d7a | 2858 | static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 | 2859 | { |
b28a02de | 2860 | void *objp; |
1da177e4 LT |
2861 | struct array_cache *ac; |
2862 | ||
dc85da15 | 2863 | #ifdef CONFIG_NUMA |
b2455396 | 2864 | if (unlikely(current->flags & (PF_SPREAD_SLAB | PF_MEMPOLICY))) { |
c61afb18 PJ |
2865 | objp = alternate_node_alloc(cachep, flags); |
2866 | if (objp != NULL) | |
2867 | return objp; | |
dc85da15 CL |
2868 | } |
2869 | #endif | |
2870 | ||
5c382300 | 2871 | check_irq_off(); |
9a2dba4b | 2872 | ac = cpu_cache_get(cachep); |
1da177e4 LT |
2873 | if (likely(ac->avail)) { |
2874 | STATS_INC_ALLOCHIT(cachep); | |
2875 | ac->touched = 1; | |
e498be7d | 2876 | objp = ac->entry[--ac->avail]; |
1da177e4 LT |
2877 | } else { |
2878 | STATS_INC_ALLOCMISS(cachep); | |
2879 | objp = cache_alloc_refill(cachep, flags); | |
2880 | } | |
5c382300 AK |
2881 | return objp; |
2882 | } | |
2883 | ||
a737b3e2 AM |
2884 | static __always_inline void *__cache_alloc(struct kmem_cache *cachep, |
2885 | gfp_t flags, void *caller) | |
5c382300 AK |
2886 | { |
2887 | unsigned long save_flags; | |
b28a02de | 2888 | void *objp; |
5c382300 AK |
2889 | |
2890 | cache_alloc_debugcheck_before(cachep, flags); | |
2891 | ||
2892 | local_irq_save(save_flags); | |
2893 | objp = ____cache_alloc(cachep, flags); | |
1da177e4 | 2894 | local_irq_restore(save_flags); |
34342e86 | 2895 | objp = cache_alloc_debugcheck_after(cachep, flags, objp, |
7fd6b141 | 2896 | caller); |
34342e86 | 2897 | prefetchw(objp); |
1da177e4 LT |
2898 | return objp; |
2899 | } | |
2900 | ||
e498be7d | 2901 | #ifdef CONFIG_NUMA |
c61afb18 | 2902 | /* |
b2455396 | 2903 | * Try allocating on another node if PF_SPREAD_SLAB|PF_MEMPOLICY. |
c61afb18 PJ |
2904 | * |
2905 | * If we are in_interrupt, then process context, including cpusets and | |
2906 | * mempolicy, may not apply and should not be used for allocation policy. | |
2907 | */ | |
2908 | static void *alternate_node_alloc(struct kmem_cache *cachep, gfp_t flags) | |
2909 | { | |
2910 | int nid_alloc, nid_here; | |
2911 | ||
2912 | if (in_interrupt()) | |
2913 | return NULL; | |
2914 | nid_alloc = nid_here = numa_node_id(); | |
2915 | if (cpuset_do_slab_mem_spread() && (cachep->flags & SLAB_MEM_SPREAD)) | |
2916 | nid_alloc = cpuset_mem_spread_node(); | |
2917 | else if (current->mempolicy) | |
2918 | nid_alloc = slab_node(current->mempolicy); | |
2919 | if (nid_alloc != nid_here) | |
2920 | return __cache_alloc_node(cachep, flags, nid_alloc); | |
2921 | return NULL; | |
2922 | } | |
2923 | ||
e498be7d CL |
2924 | /* |
2925 | * A interface to enable slab creation on nodeid | |
1da177e4 | 2926 | */ |
a737b3e2 AM |
2927 | static void *__cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, |
2928 | int nodeid) | |
e498be7d CL |
2929 | { |
2930 | struct list_head *entry; | |
b28a02de PE |
2931 | struct slab *slabp; |
2932 | struct kmem_list3 *l3; | |
2933 | void *obj; | |
b28a02de PE |
2934 | int x; |
2935 | ||
2936 | l3 = cachep->nodelists[nodeid]; | |
2937 | BUG_ON(!l3); | |
2938 | ||
a737b3e2 | 2939 | retry: |
ca3b9b91 | 2940 | check_irq_off(); |
b28a02de PE |
2941 | spin_lock(&l3->list_lock); |
2942 | entry = l3->slabs_partial.next; | |
2943 | if (entry == &l3->slabs_partial) { | |
2944 | l3->free_touched = 1; | |
2945 | entry = l3->slabs_free.next; | |
2946 | if (entry == &l3->slabs_free) | |
2947 | goto must_grow; | |
2948 | } | |
2949 | ||
2950 | slabp = list_entry(entry, struct slab, list); | |
2951 | check_spinlock_acquired_node(cachep, nodeid); | |
2952 | check_slabp(cachep, slabp); | |
2953 | ||
2954 | STATS_INC_NODEALLOCS(cachep); | |
2955 | STATS_INC_ACTIVE(cachep); | |
2956 | STATS_SET_HIGH(cachep); | |
2957 | ||
2958 | BUG_ON(slabp->inuse == cachep->num); | |
2959 | ||
78d382d7 | 2960 | obj = slab_get_obj(cachep, slabp, nodeid); |
b28a02de PE |
2961 | check_slabp(cachep, slabp); |
2962 | l3->free_objects--; | |
2963 | /* move slabp to correct slabp list: */ | |
2964 | list_del(&slabp->list); | |
2965 | ||
a737b3e2 | 2966 | if (slabp->free == BUFCTL_END) |
b28a02de | 2967 | list_add(&slabp->list, &l3->slabs_full); |
a737b3e2 | 2968 | else |
b28a02de | 2969 | list_add(&slabp->list, &l3->slabs_partial); |
e498be7d | 2970 | |
b28a02de PE |
2971 | spin_unlock(&l3->list_lock); |
2972 | goto done; | |
e498be7d | 2973 | |
a737b3e2 | 2974 | must_grow: |
b28a02de PE |
2975 | spin_unlock(&l3->list_lock); |
2976 | x = cache_grow(cachep, flags, nodeid); | |
1da177e4 | 2977 | |
b28a02de PE |
2978 | if (!x) |
2979 | return NULL; | |
e498be7d | 2980 | |
b28a02de | 2981 | goto retry; |
a737b3e2 | 2982 | done: |
b28a02de | 2983 | return obj; |
e498be7d CL |
2984 | } |
2985 | #endif | |
2986 | ||
2987 | /* | |
2988 | * Caller needs to acquire correct kmem_list's list_lock | |
2989 | */ | |
343e0d7a | 2990 | static void free_block(struct kmem_cache *cachep, void **objpp, int nr_objects, |
b28a02de | 2991 | int node) |
1da177e4 LT |
2992 | { |
2993 | int i; | |
e498be7d | 2994 | struct kmem_list3 *l3; |
1da177e4 LT |
2995 | |
2996 | for (i = 0; i < nr_objects; i++) { | |
2997 | void *objp = objpp[i]; | |
2998 | struct slab *slabp; | |
1da177e4 | 2999 | |
6ed5eb22 | 3000 | slabp = virt_to_slab(objp); |
ff69416e | 3001 | l3 = cachep->nodelists[node]; |
1da177e4 | 3002 | list_del(&slabp->list); |
ff69416e | 3003 | check_spinlock_acquired_node(cachep, node); |
1da177e4 | 3004 | check_slabp(cachep, slabp); |
78d382d7 | 3005 | slab_put_obj(cachep, slabp, objp, node); |
1da177e4 | 3006 | STATS_DEC_ACTIVE(cachep); |
e498be7d | 3007 | l3->free_objects++; |
1da177e4 LT |
3008 | check_slabp(cachep, slabp); |
3009 | ||
3010 | /* fixup slab chains */ | |
3011 | if (slabp->inuse == 0) { | |
e498be7d CL |
3012 | if (l3->free_objects > l3->free_limit) { |
3013 | l3->free_objects -= cachep->num; | |
1da177e4 LT |
3014 | slab_destroy(cachep, slabp); |
3015 | } else { | |
e498be7d | 3016 | list_add(&slabp->list, &l3->slabs_free); |
1da177e4 LT |
3017 | } |
3018 | } else { | |
3019 | /* Unconditionally move a slab to the end of the | |
3020 | * partial list on free - maximum time for the | |
3021 | * other objects to be freed, too. | |
3022 | */ | |
e498be7d | 3023 | list_add_tail(&slabp->list, &l3->slabs_partial); |
1da177e4 LT |
3024 | } |
3025 | } | |
3026 | } | |
3027 | ||
343e0d7a | 3028 | static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) |
1da177e4 LT |
3029 | { |
3030 | int batchcount; | |
e498be7d | 3031 | struct kmem_list3 *l3; |
ff69416e | 3032 | int node = numa_node_id(); |
1da177e4 LT |
3033 | |
3034 | batchcount = ac->batchcount; | |
3035 | #if DEBUG | |
3036 | BUG_ON(!batchcount || batchcount > ac->avail); | |
3037 | #endif | |
3038 | check_irq_off(); | |
ff69416e | 3039 | l3 = cachep->nodelists[node]; |
e498be7d CL |
3040 | spin_lock(&l3->list_lock); |
3041 | if (l3->shared) { | |
3042 | struct array_cache *shared_array = l3->shared; | |
b28a02de | 3043 | int max = shared_array->limit - shared_array->avail; |
1da177e4 LT |
3044 | if (max) { |
3045 | if (batchcount > max) | |
3046 | batchcount = max; | |
e498be7d | 3047 | memcpy(&(shared_array->entry[shared_array->avail]), |
b28a02de | 3048 | ac->entry, sizeof(void *) * batchcount); |
1da177e4 LT |
3049 | shared_array->avail += batchcount; |
3050 | goto free_done; | |
3051 | } | |
3052 | } | |
3053 | ||
ff69416e | 3054 | free_block(cachep, ac->entry, batchcount, node); |
a737b3e2 | 3055 | free_done: |
1da177e4 LT |
3056 | #if STATS |
3057 | { | |
3058 | int i = 0; | |
3059 | struct list_head *p; | |
3060 | ||
e498be7d CL |
3061 | p = l3->slabs_free.next; |
3062 | while (p != &(l3->slabs_free)) { | |
1da177e4 LT |
3063 | struct slab *slabp; |
3064 | ||
3065 | slabp = list_entry(p, struct slab, list); | |
3066 | BUG_ON(slabp->inuse); | |
3067 | ||
3068 | i++; | |
3069 | p = p->next; | |
3070 | } | |
3071 | STATS_SET_FREEABLE(cachep, i); | |
3072 | } | |
3073 | #endif | |
e498be7d | 3074 | spin_unlock(&l3->list_lock); |
1da177e4 | 3075 | ac->avail -= batchcount; |
a737b3e2 | 3076 | memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail); |
1da177e4 LT |
3077 | } |
3078 | ||
3079 | /* | |
a737b3e2 AM |
3080 | * Release an obj back to its cache. If the obj has a constructed state, it must |
3081 | * be in this state _before_ it is released. Called with disabled ints. | |
1da177e4 | 3082 | */ |
343e0d7a | 3083 | static inline void __cache_free(struct kmem_cache *cachep, void *objp) |
1da177e4 | 3084 | { |
9a2dba4b | 3085 | struct array_cache *ac = cpu_cache_get(cachep); |
1da177e4 LT |
3086 | |
3087 | check_irq_off(); | |
3088 | objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0)); | |
3089 | ||
e498be7d CL |
3090 | /* Make sure we are not freeing a object from another |
3091 | * node to the array cache on this cpu. | |
3092 | */ | |
3093 | #ifdef CONFIG_NUMA | |
3094 | { | |
3095 | struct slab *slabp; | |
6ed5eb22 | 3096 | slabp = virt_to_slab(objp); |
e498be7d CL |
3097 | if (unlikely(slabp->nodeid != numa_node_id())) { |
3098 | struct array_cache *alien = NULL; | |
3099 | int nodeid = slabp->nodeid; | |
a737b3e2 | 3100 | struct kmem_list3 *l3; |
e498be7d | 3101 | |
a737b3e2 | 3102 | l3 = cachep->nodelists[numa_node_id()]; |
e498be7d CL |
3103 | STATS_INC_NODEFREES(cachep); |
3104 | if (l3->alien && l3->alien[nodeid]) { | |
3105 | alien = l3->alien[nodeid]; | |
3106 | spin_lock(&alien->lock); | |
fb7faf33 RT |
3107 | if (unlikely(alien->avail == alien->limit)) { |
3108 | STATS_INC_ACOVERFLOW(cachep); | |
e498be7d | 3109 | __drain_alien_cache(cachep, |
b28a02de | 3110 | alien, nodeid); |
fb7faf33 | 3111 | } |
e498be7d CL |
3112 | alien->entry[alien->avail++] = objp; |
3113 | spin_unlock(&alien->lock); | |
3114 | } else { | |
3115 | spin_lock(&(cachep->nodelists[nodeid])-> | |
b28a02de | 3116 | list_lock); |
ff69416e | 3117 | free_block(cachep, &objp, 1, nodeid); |
e498be7d | 3118 | spin_unlock(&(cachep->nodelists[nodeid])-> |
b28a02de | 3119 | list_lock); |
e498be7d CL |
3120 | } |
3121 | return; | |
3122 | } | |
3123 | } | |
3124 | #endif | |
1da177e4 LT |
3125 | if (likely(ac->avail < ac->limit)) { |
3126 | STATS_INC_FREEHIT(cachep); | |
e498be7d | 3127 | ac->entry[ac->avail++] = objp; |
1da177e4 LT |
3128 | return; |
3129 | } else { | |
3130 | STATS_INC_FREEMISS(cachep); | |
3131 | cache_flusharray(cachep, ac); | |
e498be7d | 3132 | ac->entry[ac->avail++] = objp; |
1da177e4 LT |
3133 | } |
3134 | } | |
3135 | ||
3136 | /** | |
3137 | * kmem_cache_alloc - Allocate an object | |
3138 | * @cachep: The cache to allocate from. | |
3139 | * @flags: See kmalloc(). | |
3140 | * | |
3141 | * Allocate an object from this cache. The flags are only relevant | |
3142 | * if the cache has no available objects. | |
3143 | */ | |
343e0d7a | 3144 | void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 | 3145 | { |
7fd6b141 | 3146 | return __cache_alloc(cachep, flags, __builtin_return_address(0)); |
1da177e4 LT |
3147 | } |
3148 | EXPORT_SYMBOL(kmem_cache_alloc); | |
3149 | ||
a8c0f9a4 PE |
3150 | /** |
3151 | * kmem_cache_alloc - Allocate an object. The memory is set to zero. | |
3152 | * @cache: The cache to allocate from. | |
3153 | * @flags: See kmalloc(). | |
3154 | * | |
3155 | * Allocate an object from this cache and set the allocated memory to zero. | |
3156 | * The flags are only relevant if the cache has no available objects. | |
3157 | */ | |
3158 | void *kmem_cache_zalloc(struct kmem_cache *cache, gfp_t flags) | |
3159 | { | |
3160 | void *ret = __cache_alloc(cache, flags, __builtin_return_address(0)); | |
3161 | if (ret) | |
3162 | memset(ret, 0, obj_size(cache)); | |
3163 | return ret; | |
3164 | } | |
3165 | EXPORT_SYMBOL(kmem_cache_zalloc); | |
3166 | ||
1da177e4 LT |
3167 | /** |
3168 | * kmem_ptr_validate - check if an untrusted pointer might | |
3169 | * be a slab entry. | |
3170 | * @cachep: the cache we're checking against | |
3171 | * @ptr: pointer to validate | |
3172 | * | |
3173 | * This verifies that the untrusted pointer looks sane: | |
3174 | * it is _not_ a guarantee that the pointer is actually | |
3175 | * part of the slab cache in question, but it at least | |
3176 | * validates that the pointer can be dereferenced and | |
3177 | * looks half-way sane. | |
3178 | * | |
3179 | * Currently only used for dentry validation. | |
3180 | */ | |
343e0d7a | 3181 | int fastcall kmem_ptr_validate(struct kmem_cache *cachep, void *ptr) |
1da177e4 | 3182 | { |
b28a02de | 3183 | unsigned long addr = (unsigned long)ptr; |
1da177e4 | 3184 | unsigned long min_addr = PAGE_OFFSET; |
b28a02de | 3185 | unsigned long align_mask = BYTES_PER_WORD - 1; |
3dafccf2 | 3186 | unsigned long size = cachep->buffer_size; |
1da177e4 LT |
3187 | struct page *page; |
3188 | ||
3189 | if (unlikely(addr < min_addr)) | |
3190 | goto out; | |
3191 | if (unlikely(addr > (unsigned long)high_memory - size)) | |
3192 | goto out; | |
3193 | if (unlikely(addr & align_mask)) | |
3194 | goto out; | |
3195 | if (unlikely(!kern_addr_valid(addr))) | |
3196 | goto out; | |
3197 | if (unlikely(!kern_addr_valid(addr + size - 1))) | |
3198 | goto out; | |
3199 | page = virt_to_page(ptr); | |
3200 | if (unlikely(!PageSlab(page))) | |
3201 | goto out; | |
065d41cb | 3202 | if (unlikely(page_get_cache(page) != cachep)) |
1da177e4 LT |
3203 | goto out; |
3204 | return 1; | |
a737b3e2 | 3205 | out: |
1da177e4 LT |
3206 | return 0; |
3207 | } | |
3208 | ||
3209 | #ifdef CONFIG_NUMA | |
3210 | /** | |
3211 | * kmem_cache_alloc_node - Allocate an object on the specified node | |
3212 | * @cachep: The cache to allocate from. | |
3213 | * @flags: See kmalloc(). | |
3214 | * @nodeid: node number of the target node. | |
3215 | * | |
3216 | * Identical to kmem_cache_alloc, except that this function is slow | |
3217 | * and can sleep. And it will allocate memory on the given node, which | |
3218 | * can improve the performance for cpu bound structures. | |
e498be7d CL |
3219 | * New and improved: it will now make sure that the object gets |
3220 | * put on the correct node list so that there is no false sharing. | |
1da177e4 | 3221 | */ |
343e0d7a | 3222 | void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 | 3223 | { |
e498be7d CL |
3224 | unsigned long save_flags; |
3225 | void *ptr; | |
1da177e4 | 3226 | |
e498be7d CL |
3227 | cache_alloc_debugcheck_before(cachep, flags); |
3228 | local_irq_save(save_flags); | |
18f820f6 CL |
3229 | |
3230 | if (nodeid == -1 || nodeid == numa_node_id() || | |
a737b3e2 | 3231 | !cachep->nodelists[nodeid]) |
5c382300 AK |
3232 | ptr = ____cache_alloc(cachep, flags); |
3233 | else | |
3234 | ptr = __cache_alloc_node(cachep, flags, nodeid); | |
e498be7d | 3235 | local_irq_restore(save_flags); |
18f820f6 CL |
3236 | |
3237 | ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, | |
3238 | __builtin_return_address(0)); | |
1da177e4 | 3239 | |
e498be7d | 3240 | return ptr; |
1da177e4 LT |
3241 | } |
3242 | EXPORT_SYMBOL(kmem_cache_alloc_node); | |
3243 | ||
dd0fc66f | 3244 | void *kmalloc_node(size_t size, gfp_t flags, int node) |
97e2bde4 | 3245 | { |
343e0d7a | 3246 | struct kmem_cache *cachep; |
97e2bde4 MS |
3247 | |
3248 | cachep = kmem_find_general_cachep(size, flags); | |
3249 | if (unlikely(cachep == NULL)) | |
3250 | return NULL; | |
3251 | return kmem_cache_alloc_node(cachep, flags, node); | |
3252 | } | |
3253 | EXPORT_SYMBOL(kmalloc_node); | |
1da177e4 LT |
3254 | #endif |
3255 | ||
3256 | /** | |
3257 | * kmalloc - allocate memory | |
3258 | * @size: how many bytes of memory are required. | |
3259 | * @flags: the type of memory to allocate. | |
911851e6 | 3260 | * @caller: function caller for debug tracking of the caller |
1da177e4 LT |
3261 | * |
3262 | * kmalloc is the normal method of allocating memory | |
3263 | * in the kernel. | |
3264 | * | |
3265 | * The @flags argument may be one of: | |
3266 | * | |
3267 | * %GFP_USER - Allocate memory on behalf of user. May sleep. | |
3268 | * | |
3269 | * %GFP_KERNEL - Allocate normal kernel ram. May sleep. | |
3270 | * | |
3271 | * %GFP_ATOMIC - Allocation will not sleep. Use inside interrupt handlers. | |
3272 | * | |
3273 | * Additionally, the %GFP_DMA flag may be set to indicate the memory | |
3274 | * must be suitable for DMA. This can mean different things on different | |
3275 | * platforms. For example, on i386, it means that the memory must come | |
3276 | * from the first 16MB. | |
3277 | */ | |
7fd6b141 PE |
3278 | static __always_inline void *__do_kmalloc(size_t size, gfp_t flags, |
3279 | void *caller) | |
1da177e4 | 3280 | { |
343e0d7a | 3281 | struct kmem_cache *cachep; |
1da177e4 | 3282 | |
97e2bde4 MS |
3283 | /* If you want to save a few bytes .text space: replace |
3284 | * __ with kmem_. | |
3285 | * Then kmalloc uses the uninlined functions instead of the inline | |
3286 | * functions. | |
3287 | */ | |
3288 | cachep = __find_general_cachep(size, flags); | |
dbdb9045 AM |
3289 | if (unlikely(cachep == NULL)) |
3290 | return NULL; | |
7fd6b141 PE |
3291 | return __cache_alloc(cachep, flags, caller); |
3292 | } | |
3293 | ||
7fd6b141 PE |
3294 | |
3295 | void *__kmalloc(size_t size, gfp_t flags) | |
3296 | { | |
871751e2 | 3297 | #ifndef CONFIG_DEBUG_SLAB |
7fd6b141 | 3298 | return __do_kmalloc(size, flags, NULL); |
871751e2 AV |
3299 | #else |
3300 | return __do_kmalloc(size, flags, __builtin_return_address(0)); | |
3301 | #endif | |
1da177e4 LT |
3302 | } |
3303 | EXPORT_SYMBOL(__kmalloc); | |
3304 | ||
871751e2 | 3305 | #ifdef CONFIG_DEBUG_SLAB |
7fd6b141 PE |
3306 | void *__kmalloc_track_caller(size_t size, gfp_t flags, void *caller) |
3307 | { | |
3308 | return __do_kmalloc(size, flags, caller); | |
3309 | } | |
3310 | EXPORT_SYMBOL(__kmalloc_track_caller); | |
7fd6b141 PE |
3311 | #endif |
3312 | ||
1da177e4 LT |
3313 | #ifdef CONFIG_SMP |
3314 | /** | |
3315 | * __alloc_percpu - allocate one copy of the object for every present | |
3316 | * cpu in the system, zeroing them. | |
3317 | * Objects should be dereferenced using the per_cpu_ptr macro only. | |
3318 | * | |
3319 | * @size: how many bytes of memory are required. | |
1da177e4 | 3320 | */ |
f9f75005 | 3321 | void *__alloc_percpu(size_t size) |
1da177e4 LT |
3322 | { |
3323 | int i; | |
b28a02de | 3324 | struct percpu_data *pdata = kmalloc(sizeof(*pdata), GFP_KERNEL); |
1da177e4 LT |
3325 | |
3326 | if (!pdata) | |
3327 | return NULL; | |
3328 | ||
e498be7d CL |
3329 | /* |
3330 | * Cannot use for_each_online_cpu since a cpu may come online | |
3331 | * and we have no way of figuring out how to fix the array | |
3332 | * that we have allocated then.... | |
3333 | */ | |
0a945022 | 3334 | for_each_possible_cpu(i) { |
e498be7d CL |
3335 | int node = cpu_to_node(i); |
3336 | ||
3337 | if (node_online(node)) | |
3338 | pdata->ptrs[i] = kmalloc_node(size, GFP_KERNEL, node); | |
3339 | else | |
3340 | pdata->ptrs[i] = kmalloc(size, GFP_KERNEL); | |
1da177e4 LT |
3341 | |
3342 | if (!pdata->ptrs[i]) | |
3343 | goto unwind_oom; | |
3344 | memset(pdata->ptrs[i], 0, size); | |
3345 | } | |
3346 | ||
3347 | /* Catch derefs w/o wrappers */ | |
b28a02de | 3348 | return (void *)(~(unsigned long)pdata); |
1da177e4 | 3349 | |
a737b3e2 | 3350 | unwind_oom: |
1da177e4 LT |
3351 | while (--i >= 0) { |
3352 | if (!cpu_possible(i)) | |
3353 | continue; | |
3354 | kfree(pdata->ptrs[i]); | |
3355 | } | |
3356 | kfree(pdata); | |
3357 | return NULL; | |
3358 | } | |
3359 | EXPORT_SYMBOL(__alloc_percpu); | |
3360 | #endif | |
3361 | ||
3362 | /** | |
3363 | * kmem_cache_free - Deallocate an object | |
3364 | * @cachep: The cache the allocation was from. | |
3365 | * @objp: The previously allocated object. | |
3366 | * | |
3367 | * Free an object which was previously allocated from this | |
3368 | * cache. | |
3369 | */ | |
343e0d7a | 3370 | void kmem_cache_free(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
3371 | { |
3372 | unsigned long flags; | |
3373 | ||
3374 | local_irq_save(flags); | |
3375 | __cache_free(cachep, objp); | |
3376 | local_irq_restore(flags); | |
3377 | } | |
3378 | EXPORT_SYMBOL(kmem_cache_free); | |
3379 | ||
1da177e4 LT |
3380 | /** |
3381 | * kfree - free previously allocated memory | |
3382 | * @objp: pointer returned by kmalloc. | |
3383 | * | |
80e93eff PE |
3384 | * If @objp is NULL, no operation is performed. |
3385 | * | |
1da177e4 LT |
3386 | * Don't free memory not originally allocated by kmalloc() |
3387 | * or you will run into trouble. | |
3388 | */ | |
3389 | void kfree(const void *objp) | |
3390 | { | |
343e0d7a | 3391 | struct kmem_cache *c; |
1da177e4 LT |
3392 | unsigned long flags; |
3393 | ||
3394 | if (unlikely(!objp)) | |
3395 | return; | |
3396 | local_irq_save(flags); | |
3397 | kfree_debugcheck(objp); | |
6ed5eb22 | 3398 | c = virt_to_cache(objp); |
3dafccf2 | 3399 | mutex_debug_check_no_locks_freed(objp, obj_size(c)); |
b28a02de | 3400 | __cache_free(c, (void *)objp); |
1da177e4 LT |
3401 | local_irq_restore(flags); |
3402 | } | |
3403 | EXPORT_SYMBOL(kfree); | |
3404 | ||
3405 | #ifdef CONFIG_SMP | |
3406 | /** | |
3407 | * free_percpu - free previously allocated percpu memory | |
3408 | * @objp: pointer returned by alloc_percpu. | |
3409 | * | |
3410 | * Don't free memory not originally allocated by alloc_percpu() | |
3411 | * The complemented objp is to check for that. | |
3412 | */ | |
b28a02de | 3413 | void free_percpu(const void *objp) |
1da177e4 LT |
3414 | { |
3415 | int i; | |
b28a02de | 3416 | struct percpu_data *p = (struct percpu_data *)(~(unsigned long)objp); |
1da177e4 | 3417 | |
e498be7d CL |
3418 | /* |
3419 | * We allocate for all cpus so we cannot use for online cpu here. | |
3420 | */ | |
0a945022 | 3421 | for_each_possible_cpu(i) |
b28a02de | 3422 | kfree(p->ptrs[i]); |
1da177e4 LT |
3423 | kfree(p); |
3424 | } | |
3425 | EXPORT_SYMBOL(free_percpu); | |
3426 | #endif | |
3427 | ||
343e0d7a | 3428 | unsigned int kmem_cache_size(struct kmem_cache *cachep) |
1da177e4 | 3429 | { |
3dafccf2 | 3430 | return obj_size(cachep); |
1da177e4 LT |
3431 | } |
3432 | EXPORT_SYMBOL(kmem_cache_size); | |
3433 | ||
343e0d7a | 3434 | const char *kmem_cache_name(struct kmem_cache *cachep) |
1944972d ACM |
3435 | { |
3436 | return cachep->name; | |
3437 | } | |
3438 | EXPORT_SYMBOL_GPL(kmem_cache_name); | |
3439 | ||
e498be7d | 3440 | /* |
0718dc2a | 3441 | * This initializes kmem_list3 or resizes varioius caches for all nodes. |
e498be7d | 3442 | */ |
343e0d7a | 3443 | static int alloc_kmemlist(struct kmem_cache *cachep) |
e498be7d CL |
3444 | { |
3445 | int node; | |
3446 | struct kmem_list3 *l3; | |
cafeb02e CL |
3447 | struct array_cache *new_shared; |
3448 | struct array_cache **new_alien; | |
e498be7d CL |
3449 | |
3450 | for_each_online_node(node) { | |
cafeb02e | 3451 | |
a737b3e2 AM |
3452 | new_alien = alloc_alien_cache(node, cachep->limit); |
3453 | if (!new_alien) | |
e498be7d | 3454 | goto fail; |
cafeb02e | 3455 | |
0718dc2a CL |
3456 | new_shared = alloc_arraycache(node, |
3457 | cachep->shared*cachep->batchcount, | |
a737b3e2 | 3458 | 0xbaadf00d); |
0718dc2a CL |
3459 | if (!new_shared) { |
3460 | free_alien_cache(new_alien); | |
e498be7d | 3461 | goto fail; |
0718dc2a | 3462 | } |
cafeb02e | 3463 | |
a737b3e2 AM |
3464 | l3 = cachep->nodelists[node]; |
3465 | if (l3) { | |
cafeb02e CL |
3466 | struct array_cache *shared = l3->shared; |
3467 | ||
e498be7d CL |
3468 | spin_lock_irq(&l3->list_lock); |
3469 | ||
cafeb02e | 3470 | if (shared) |
0718dc2a CL |
3471 | free_block(cachep, shared->entry, |
3472 | shared->avail, node); | |
e498be7d | 3473 | |
cafeb02e CL |
3474 | l3->shared = new_shared; |
3475 | if (!l3->alien) { | |
e498be7d CL |
3476 | l3->alien = new_alien; |
3477 | new_alien = NULL; | |
3478 | } | |
b28a02de | 3479 | l3->free_limit = (1 + nr_cpus_node(node)) * |
a737b3e2 | 3480 | cachep->batchcount + cachep->num; |
e498be7d | 3481 | spin_unlock_irq(&l3->list_lock); |
cafeb02e | 3482 | kfree(shared); |
e498be7d CL |
3483 | free_alien_cache(new_alien); |
3484 | continue; | |
3485 | } | |
a737b3e2 | 3486 | l3 = kmalloc_node(sizeof(struct kmem_list3), GFP_KERNEL, node); |
0718dc2a CL |
3487 | if (!l3) { |
3488 | free_alien_cache(new_alien); | |
3489 | kfree(new_shared); | |
e498be7d | 3490 | goto fail; |
0718dc2a | 3491 | } |
e498be7d CL |
3492 | |
3493 | kmem_list3_init(l3); | |
3494 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + | |
a737b3e2 | 3495 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
cafeb02e | 3496 | l3->shared = new_shared; |
e498be7d | 3497 | l3->alien = new_alien; |
b28a02de | 3498 | l3->free_limit = (1 + nr_cpus_node(node)) * |
a737b3e2 | 3499 | cachep->batchcount + cachep->num; |
e498be7d CL |
3500 | cachep->nodelists[node] = l3; |
3501 | } | |
cafeb02e | 3502 | return 0; |
0718dc2a | 3503 | |
a737b3e2 | 3504 | fail: |
0718dc2a CL |
3505 | if (!cachep->next.next) { |
3506 | /* Cache is not active yet. Roll back what we did */ | |
3507 | node--; | |
3508 | while (node >= 0) { | |
3509 | if (cachep->nodelists[node]) { | |
3510 | l3 = cachep->nodelists[node]; | |
3511 | ||
3512 | kfree(l3->shared); | |
3513 | free_alien_cache(l3->alien); | |
3514 | kfree(l3); | |
3515 | cachep->nodelists[node] = NULL; | |
3516 | } | |
3517 | node--; | |
3518 | } | |
3519 | } | |
cafeb02e | 3520 | return -ENOMEM; |
e498be7d CL |
3521 | } |
3522 | ||
1da177e4 | 3523 | struct ccupdate_struct { |
343e0d7a | 3524 | struct kmem_cache *cachep; |
1da177e4 LT |
3525 | struct array_cache *new[NR_CPUS]; |
3526 | }; | |
3527 | ||
3528 | static void do_ccupdate_local(void *info) | |
3529 | { | |
a737b3e2 | 3530 | struct ccupdate_struct *new = info; |
1da177e4 LT |
3531 | struct array_cache *old; |
3532 | ||
3533 | check_irq_off(); | |
9a2dba4b | 3534 | old = cpu_cache_get(new->cachep); |
e498be7d | 3535 | |
1da177e4 LT |
3536 | new->cachep->array[smp_processor_id()] = new->new[smp_processor_id()]; |
3537 | new->new[smp_processor_id()] = old; | |
3538 | } | |
3539 | ||
b5d8ca7c | 3540 | /* Always called with the cache_chain_mutex held */ |
a737b3e2 AM |
3541 | static int do_tune_cpucache(struct kmem_cache *cachep, int limit, |
3542 | int batchcount, int shared) | |
1da177e4 LT |
3543 | { |
3544 | struct ccupdate_struct new; | |
e498be7d | 3545 | int i, err; |
1da177e4 | 3546 | |
b28a02de | 3547 | memset(&new.new, 0, sizeof(new.new)); |
e498be7d | 3548 | for_each_online_cpu(i) { |
a737b3e2 AM |
3549 | new.new[i] = alloc_arraycache(cpu_to_node(i), limit, |
3550 | batchcount); | |
e498be7d | 3551 | if (!new.new[i]) { |
b28a02de PE |
3552 | for (i--; i >= 0; i--) |
3553 | kfree(new.new[i]); | |
e498be7d | 3554 | return -ENOMEM; |
1da177e4 LT |
3555 | } |
3556 | } | |
3557 | new.cachep = cachep; | |
3558 | ||
a07fa394 | 3559 | on_each_cpu(do_ccupdate_local, (void *)&new, 1, 1); |
e498be7d | 3560 | |
1da177e4 | 3561 | check_irq_on(); |
1da177e4 LT |
3562 | cachep->batchcount = batchcount; |
3563 | cachep->limit = limit; | |
e498be7d | 3564 | cachep->shared = shared; |
1da177e4 | 3565 | |
e498be7d | 3566 | for_each_online_cpu(i) { |
1da177e4 LT |
3567 | struct array_cache *ccold = new.new[i]; |
3568 | if (!ccold) | |
3569 | continue; | |
e498be7d | 3570 | spin_lock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
ff69416e | 3571 | free_block(cachep, ccold->entry, ccold->avail, cpu_to_node(i)); |
e498be7d | 3572 | spin_unlock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
1da177e4 LT |
3573 | kfree(ccold); |
3574 | } | |
1da177e4 | 3575 | |
e498be7d CL |
3576 | err = alloc_kmemlist(cachep); |
3577 | if (err) { | |
3578 | printk(KERN_ERR "alloc_kmemlist failed for %s, error %d.\n", | |
b28a02de | 3579 | cachep->name, -err); |
e498be7d | 3580 | BUG(); |
1da177e4 | 3581 | } |
1da177e4 LT |
3582 | return 0; |
3583 | } | |
3584 | ||
b5d8ca7c | 3585 | /* Called with cache_chain_mutex held always */ |
343e0d7a | 3586 | static void enable_cpucache(struct kmem_cache *cachep) |
1da177e4 LT |
3587 | { |
3588 | int err; | |
3589 | int limit, shared; | |
3590 | ||
a737b3e2 AM |
3591 | /* |
3592 | * The head array serves three purposes: | |
1da177e4 LT |
3593 | * - create a LIFO ordering, i.e. return objects that are cache-warm |
3594 | * - reduce the number of spinlock operations. | |
a737b3e2 | 3595 | * - reduce the number of linked list operations on the slab and |
1da177e4 LT |
3596 | * bufctl chains: array operations are cheaper. |
3597 | * The numbers are guessed, we should auto-tune as described by | |
3598 | * Bonwick. | |
3599 | */ | |
3dafccf2 | 3600 | if (cachep->buffer_size > 131072) |
1da177e4 | 3601 | limit = 1; |
3dafccf2 | 3602 | else if (cachep->buffer_size > PAGE_SIZE) |
1da177e4 | 3603 | limit = 8; |
3dafccf2 | 3604 | else if (cachep->buffer_size > 1024) |
1da177e4 | 3605 | limit = 24; |
3dafccf2 | 3606 | else if (cachep->buffer_size > 256) |
1da177e4 LT |
3607 | limit = 54; |
3608 | else | |
3609 | limit = 120; | |
3610 | ||
a737b3e2 AM |
3611 | /* |
3612 | * CPU bound tasks (e.g. network routing) can exhibit cpu bound | |
1da177e4 LT |
3613 | * allocation behaviour: Most allocs on one cpu, most free operations |
3614 | * on another cpu. For these cases, an efficient object passing between | |
3615 | * cpus is necessary. This is provided by a shared array. The array | |
3616 | * replaces Bonwick's magazine layer. | |
3617 | * On uniprocessor, it's functionally equivalent (but less efficient) | |
3618 | * to a larger limit. Thus disabled by default. | |
3619 | */ | |
3620 | shared = 0; | |
3621 | #ifdef CONFIG_SMP | |
3dafccf2 | 3622 | if (cachep->buffer_size <= PAGE_SIZE) |
1da177e4 LT |
3623 | shared = 8; |
3624 | #endif | |
3625 | ||
3626 | #if DEBUG | |
a737b3e2 AM |
3627 | /* |
3628 | * With debugging enabled, large batchcount lead to excessively long | |
3629 | * periods with disabled local interrupts. Limit the batchcount | |
1da177e4 LT |
3630 | */ |
3631 | if (limit > 32) | |
3632 | limit = 32; | |
3633 | #endif | |
b28a02de | 3634 | err = do_tune_cpucache(cachep, limit, (limit + 1) / 2, shared); |
1da177e4 LT |
3635 | if (err) |
3636 | printk(KERN_ERR "enable_cpucache failed for %s, error %d.\n", | |
b28a02de | 3637 | cachep->name, -err); |
1da177e4 LT |
3638 | } |
3639 | ||
1b55253a CL |
3640 | /* |
3641 | * Drain an array if it contains any elements taking the l3 lock only if | |
b18e7e65 CL |
3642 | * necessary. Note that the l3 listlock also protects the array_cache |
3643 | * if drain_array() is used on the shared array. | |
1b55253a CL |
3644 | */ |
3645 | void drain_array(struct kmem_cache *cachep, struct kmem_list3 *l3, | |
3646 | struct array_cache *ac, int force, int node) | |
1da177e4 LT |
3647 | { |
3648 | int tofree; | |
3649 | ||
1b55253a CL |
3650 | if (!ac || !ac->avail) |
3651 | return; | |
1da177e4 LT |
3652 | if (ac->touched && !force) { |
3653 | ac->touched = 0; | |
b18e7e65 | 3654 | } else { |
1b55253a | 3655 | spin_lock_irq(&l3->list_lock); |
b18e7e65 CL |
3656 | if (ac->avail) { |
3657 | tofree = force ? ac->avail : (ac->limit + 4) / 5; | |
3658 | if (tofree > ac->avail) | |
3659 | tofree = (ac->avail + 1) / 2; | |
3660 | free_block(cachep, ac->entry, tofree, node); | |
3661 | ac->avail -= tofree; | |
3662 | memmove(ac->entry, &(ac->entry[tofree]), | |
3663 | sizeof(void *) * ac->avail); | |
3664 | } | |
1b55253a | 3665 | spin_unlock_irq(&l3->list_lock); |
1da177e4 LT |
3666 | } |
3667 | } | |
3668 | ||
3669 | /** | |
3670 | * cache_reap - Reclaim memory from caches. | |
1e5d5331 | 3671 | * @unused: unused parameter |
1da177e4 LT |
3672 | * |
3673 | * Called from workqueue/eventd every few seconds. | |
3674 | * Purpose: | |
3675 | * - clear the per-cpu caches for this CPU. | |
3676 | * - return freeable pages to the main free memory pool. | |
3677 | * | |
a737b3e2 AM |
3678 | * If we cannot acquire the cache chain mutex then just give up - we'll try |
3679 | * again on the next iteration. | |
1da177e4 LT |
3680 | */ |
3681 | static void cache_reap(void *unused) | |
3682 | { | |
3683 | struct list_head *walk; | |
e498be7d | 3684 | struct kmem_list3 *l3; |
aab2207c | 3685 | int node = numa_node_id(); |
1da177e4 | 3686 | |
fc0abb14 | 3687 | if (!mutex_trylock(&cache_chain_mutex)) { |
1da177e4 | 3688 | /* Give up. Setup the next iteration. */ |
b28a02de PE |
3689 | schedule_delayed_work(&__get_cpu_var(reap_work), |
3690 | REAPTIMEOUT_CPUC); | |
1da177e4 LT |
3691 | return; |
3692 | } | |
3693 | ||
3694 | list_for_each(walk, &cache_chain) { | |
343e0d7a | 3695 | struct kmem_cache *searchp; |
b28a02de | 3696 | struct list_head *p; |
1da177e4 LT |
3697 | int tofree; |
3698 | struct slab *slabp; | |
3699 | ||
343e0d7a | 3700 | searchp = list_entry(walk, struct kmem_cache, next); |
1da177e4 LT |
3701 | check_irq_on(); |
3702 | ||
35386e3b CL |
3703 | /* |
3704 | * We only take the l3 lock if absolutely necessary and we | |
3705 | * have established with reasonable certainty that | |
3706 | * we can do some work if the lock was obtained. | |
3707 | */ | |
aab2207c | 3708 | l3 = searchp->nodelists[node]; |
35386e3b | 3709 | |
8fce4d8e | 3710 | reap_alien(searchp, l3); |
1da177e4 | 3711 | |
aab2207c | 3712 | drain_array(searchp, l3, cpu_cache_get(searchp), 0, node); |
1da177e4 | 3713 | |
35386e3b CL |
3714 | /* |
3715 | * These are racy checks but it does not matter | |
3716 | * if we skip one check or scan twice. | |
3717 | */ | |
e498be7d | 3718 | if (time_after(l3->next_reap, jiffies)) |
35386e3b | 3719 | goto next; |
1da177e4 | 3720 | |
e498be7d | 3721 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3; |
1da177e4 | 3722 | |
aab2207c | 3723 | drain_array(searchp, l3, l3->shared, 0, node); |
1da177e4 | 3724 | |
e498be7d CL |
3725 | if (l3->free_touched) { |
3726 | l3->free_touched = 0; | |
35386e3b | 3727 | goto next; |
1da177e4 LT |
3728 | } |
3729 | ||
a737b3e2 AM |
3730 | tofree = (l3->free_limit + 5 * searchp->num - 1) / |
3731 | (5 * searchp->num); | |
1da177e4 | 3732 | do { |
35386e3b CL |
3733 | /* |
3734 | * Do not lock if there are no free blocks. | |
3735 | */ | |
3736 | if (list_empty(&l3->slabs_free)) | |
3737 | break; | |
3738 | ||
3739 | spin_lock_irq(&l3->list_lock); | |
e498be7d | 3740 | p = l3->slabs_free.next; |
35386e3b CL |
3741 | if (p == &(l3->slabs_free)) { |
3742 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 3743 | break; |
35386e3b | 3744 | } |
1da177e4 LT |
3745 | |
3746 | slabp = list_entry(p, struct slab, list); | |
3747 | BUG_ON(slabp->inuse); | |
3748 | list_del(&slabp->list); | |
3749 | STATS_INC_REAPED(searchp); | |
3750 | ||
a737b3e2 AM |
3751 | /* |
3752 | * Safe to drop the lock. The slab is no longer linked | |
3753 | * to the cache. searchp cannot disappear, we hold | |
1da177e4 LT |
3754 | * cache_chain_lock |
3755 | */ | |
e498be7d CL |
3756 | l3->free_objects -= searchp->num; |
3757 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 3758 | slab_destroy(searchp, slabp); |
b28a02de | 3759 | } while (--tofree > 0); |
35386e3b | 3760 | next: |
1da177e4 LT |
3761 | cond_resched(); |
3762 | } | |
3763 | check_irq_on(); | |
fc0abb14 | 3764 | mutex_unlock(&cache_chain_mutex); |
8fce4d8e | 3765 | next_reap_node(); |
a737b3e2 | 3766 | /* Set up the next iteration */ |
cd61ef62 | 3767 | schedule_delayed_work(&__get_cpu_var(reap_work), REAPTIMEOUT_CPUC); |
1da177e4 LT |
3768 | } |
3769 | ||
3770 | #ifdef CONFIG_PROC_FS | |
3771 | ||
85289f98 | 3772 | static void print_slabinfo_header(struct seq_file *m) |
1da177e4 | 3773 | { |
85289f98 PE |
3774 | /* |
3775 | * Output format version, so at least we can change it | |
3776 | * without _too_ many complaints. | |
3777 | */ | |
1da177e4 | 3778 | #if STATS |
85289f98 | 3779 | seq_puts(m, "slabinfo - version: 2.1 (statistics)\n"); |
1da177e4 | 3780 | #else |
85289f98 | 3781 | seq_puts(m, "slabinfo - version: 2.1\n"); |
1da177e4 | 3782 | #endif |
85289f98 PE |
3783 | seq_puts(m, "# name <active_objs> <num_objs> <objsize> " |
3784 | "<objperslab> <pagesperslab>"); | |
3785 | seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); | |
3786 | seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); | |
1da177e4 | 3787 | #if STATS |
85289f98 | 3788 | seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> " |
fb7faf33 | 3789 | "<error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>"); |
85289f98 | 3790 | seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>"); |
1da177e4 | 3791 | #endif |
85289f98 PE |
3792 | seq_putc(m, '\n'); |
3793 | } | |
3794 | ||
3795 | static void *s_start(struct seq_file *m, loff_t *pos) | |
3796 | { | |
3797 | loff_t n = *pos; | |
3798 | struct list_head *p; | |
3799 | ||
fc0abb14 | 3800 | mutex_lock(&cache_chain_mutex); |
85289f98 PE |
3801 | if (!n) |
3802 | print_slabinfo_header(m); | |
1da177e4 LT |
3803 | p = cache_chain.next; |
3804 | while (n--) { | |
3805 | p = p->next; | |
3806 | if (p == &cache_chain) | |
3807 | return NULL; | |
3808 | } | |
343e0d7a | 3809 | return list_entry(p, struct kmem_cache, next); |
1da177e4 LT |
3810 | } |
3811 | ||
3812 | static void *s_next(struct seq_file *m, void *p, loff_t *pos) | |
3813 | { | |
343e0d7a | 3814 | struct kmem_cache *cachep = p; |
1da177e4 | 3815 | ++*pos; |
a737b3e2 AM |
3816 | return cachep->next.next == &cache_chain ? |
3817 | NULL : list_entry(cachep->next.next, struct kmem_cache, next); | |
1da177e4 LT |
3818 | } |
3819 | ||
3820 | static void s_stop(struct seq_file *m, void *p) | |
3821 | { | |
fc0abb14 | 3822 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
3823 | } |
3824 | ||
3825 | static int s_show(struct seq_file *m, void *p) | |
3826 | { | |
343e0d7a | 3827 | struct kmem_cache *cachep = p; |
1da177e4 | 3828 | struct list_head *q; |
b28a02de PE |
3829 | struct slab *slabp; |
3830 | unsigned long active_objs; | |
3831 | unsigned long num_objs; | |
3832 | unsigned long active_slabs = 0; | |
3833 | unsigned long num_slabs, free_objects = 0, shared_avail = 0; | |
e498be7d | 3834 | const char *name; |
1da177e4 | 3835 | char *error = NULL; |
e498be7d CL |
3836 | int node; |
3837 | struct kmem_list3 *l3; | |
1da177e4 | 3838 | |
1da177e4 LT |
3839 | active_objs = 0; |
3840 | num_slabs = 0; | |
e498be7d CL |
3841 | for_each_online_node(node) { |
3842 | l3 = cachep->nodelists[node]; | |
3843 | if (!l3) | |
3844 | continue; | |
3845 | ||
ca3b9b91 RT |
3846 | check_irq_on(); |
3847 | spin_lock_irq(&l3->list_lock); | |
e498be7d | 3848 | |
b28a02de | 3849 | list_for_each(q, &l3->slabs_full) { |
e498be7d CL |
3850 | slabp = list_entry(q, struct slab, list); |
3851 | if (slabp->inuse != cachep->num && !error) | |
3852 | error = "slabs_full accounting error"; | |
3853 | active_objs += cachep->num; | |
3854 | active_slabs++; | |
3855 | } | |
b28a02de | 3856 | list_for_each(q, &l3->slabs_partial) { |
e498be7d CL |
3857 | slabp = list_entry(q, struct slab, list); |
3858 | if (slabp->inuse == cachep->num && !error) | |
3859 | error = "slabs_partial inuse accounting error"; | |
3860 | if (!slabp->inuse && !error) | |
3861 | error = "slabs_partial/inuse accounting error"; | |
3862 | active_objs += slabp->inuse; | |
3863 | active_slabs++; | |
3864 | } | |
b28a02de | 3865 | list_for_each(q, &l3->slabs_free) { |
e498be7d CL |
3866 | slabp = list_entry(q, struct slab, list); |
3867 | if (slabp->inuse && !error) | |
3868 | error = "slabs_free/inuse accounting error"; | |
3869 | num_slabs++; | |
3870 | } | |
3871 | free_objects += l3->free_objects; | |
4484ebf1 RT |
3872 | if (l3->shared) |
3873 | shared_avail += l3->shared->avail; | |
e498be7d | 3874 | |
ca3b9b91 | 3875 | spin_unlock_irq(&l3->list_lock); |
1da177e4 | 3876 | } |
b28a02de PE |
3877 | num_slabs += active_slabs; |
3878 | num_objs = num_slabs * cachep->num; | |
e498be7d | 3879 | if (num_objs - active_objs != free_objects && !error) |
1da177e4 LT |
3880 | error = "free_objects accounting error"; |
3881 | ||
b28a02de | 3882 | name = cachep->name; |
1da177e4 LT |
3883 | if (error) |
3884 | printk(KERN_ERR "slab: cache %s error: %s\n", name, error); | |
3885 | ||
3886 | seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", | |
3dafccf2 | 3887 | name, active_objs, num_objs, cachep->buffer_size, |
b28a02de | 3888 | cachep->num, (1 << cachep->gfporder)); |
1da177e4 | 3889 | seq_printf(m, " : tunables %4u %4u %4u", |
b28a02de | 3890 | cachep->limit, cachep->batchcount, cachep->shared); |
e498be7d | 3891 | seq_printf(m, " : slabdata %6lu %6lu %6lu", |
b28a02de | 3892 | active_slabs, num_slabs, shared_avail); |
1da177e4 | 3893 | #if STATS |
b28a02de | 3894 | { /* list3 stats */ |
1da177e4 LT |
3895 | unsigned long high = cachep->high_mark; |
3896 | unsigned long allocs = cachep->num_allocations; | |
3897 | unsigned long grown = cachep->grown; | |
3898 | unsigned long reaped = cachep->reaped; | |
3899 | unsigned long errors = cachep->errors; | |
3900 | unsigned long max_freeable = cachep->max_freeable; | |
1da177e4 | 3901 | unsigned long node_allocs = cachep->node_allocs; |
e498be7d | 3902 | unsigned long node_frees = cachep->node_frees; |
fb7faf33 | 3903 | unsigned long overflows = cachep->node_overflow; |
1da177e4 | 3904 | |
e498be7d | 3905 | seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu \ |
fb7faf33 | 3906 | %4lu %4lu %4lu %4lu %4lu", allocs, high, grown, |
a737b3e2 | 3907 | reaped, errors, max_freeable, node_allocs, |
fb7faf33 | 3908 | node_frees, overflows); |
1da177e4 LT |
3909 | } |
3910 | /* cpu stats */ | |
3911 | { | |
3912 | unsigned long allochit = atomic_read(&cachep->allochit); | |
3913 | unsigned long allocmiss = atomic_read(&cachep->allocmiss); | |
3914 | unsigned long freehit = atomic_read(&cachep->freehit); | |
3915 | unsigned long freemiss = atomic_read(&cachep->freemiss); | |
3916 | ||
3917 | seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", | |
b28a02de | 3918 | allochit, allocmiss, freehit, freemiss); |
1da177e4 LT |
3919 | } |
3920 | #endif | |
3921 | seq_putc(m, '\n'); | |
1da177e4 LT |
3922 | return 0; |
3923 | } | |
3924 | ||
3925 | /* | |
3926 | * slabinfo_op - iterator that generates /proc/slabinfo | |
3927 | * | |
3928 | * Output layout: | |
3929 | * cache-name | |
3930 | * num-active-objs | |
3931 | * total-objs | |
3932 | * object size | |
3933 | * num-active-slabs | |
3934 | * total-slabs | |
3935 | * num-pages-per-slab | |
3936 | * + further values on SMP and with statistics enabled | |
3937 | */ | |
3938 | ||
3939 | struct seq_operations slabinfo_op = { | |
b28a02de PE |
3940 | .start = s_start, |
3941 | .next = s_next, | |
3942 | .stop = s_stop, | |
3943 | .show = s_show, | |
1da177e4 LT |
3944 | }; |
3945 | ||
3946 | #define MAX_SLABINFO_WRITE 128 | |
3947 | /** | |
3948 | * slabinfo_write - Tuning for the slab allocator | |
3949 | * @file: unused | |
3950 | * @buffer: user buffer | |
3951 | * @count: data length | |
3952 | * @ppos: unused | |
3953 | */ | |
b28a02de PE |
3954 | ssize_t slabinfo_write(struct file *file, const char __user * buffer, |
3955 | size_t count, loff_t *ppos) | |
1da177e4 | 3956 | { |
b28a02de | 3957 | char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; |
1da177e4 LT |
3958 | int limit, batchcount, shared, res; |
3959 | struct list_head *p; | |
b28a02de | 3960 | |
1da177e4 LT |
3961 | if (count > MAX_SLABINFO_WRITE) |
3962 | return -EINVAL; | |
3963 | if (copy_from_user(&kbuf, buffer, count)) | |
3964 | return -EFAULT; | |
b28a02de | 3965 | kbuf[MAX_SLABINFO_WRITE] = '\0'; |
1da177e4 LT |
3966 | |
3967 | tmp = strchr(kbuf, ' '); | |
3968 | if (!tmp) | |
3969 | return -EINVAL; | |
3970 | *tmp = '\0'; | |
3971 | tmp++; | |
3972 | if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) | |
3973 | return -EINVAL; | |
3974 | ||
3975 | /* Find the cache in the chain of caches. */ | |
fc0abb14 | 3976 | mutex_lock(&cache_chain_mutex); |
1da177e4 | 3977 | res = -EINVAL; |
b28a02de | 3978 | list_for_each(p, &cache_chain) { |
a737b3e2 | 3979 | struct kmem_cache *cachep; |
1da177e4 | 3980 | |
a737b3e2 | 3981 | cachep = list_entry(p, struct kmem_cache, next); |
1da177e4 | 3982 | if (!strcmp(cachep->name, kbuf)) { |
a737b3e2 AM |
3983 | if (limit < 1 || batchcount < 1 || |
3984 | batchcount > limit || shared < 0) { | |
e498be7d | 3985 | res = 0; |
1da177e4 | 3986 | } else { |
e498be7d | 3987 | res = do_tune_cpucache(cachep, limit, |
b28a02de | 3988 | batchcount, shared); |
1da177e4 LT |
3989 | } |
3990 | break; | |
3991 | } | |
3992 | } | |
fc0abb14 | 3993 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
3994 | if (res >= 0) |
3995 | res = count; | |
3996 | return res; | |
3997 | } | |
871751e2 AV |
3998 | |
3999 | #ifdef CONFIG_DEBUG_SLAB_LEAK | |
4000 | ||
4001 | static void *leaks_start(struct seq_file *m, loff_t *pos) | |
4002 | { | |
4003 | loff_t n = *pos; | |
4004 | struct list_head *p; | |
4005 | ||
4006 | mutex_lock(&cache_chain_mutex); | |
4007 | p = cache_chain.next; | |
4008 | while (n--) { | |
4009 | p = p->next; | |
4010 | if (p == &cache_chain) | |
4011 | return NULL; | |
4012 | } | |
4013 | return list_entry(p, struct kmem_cache, next); | |
4014 | } | |
4015 | ||
4016 | static inline int add_caller(unsigned long *n, unsigned long v) | |
4017 | { | |
4018 | unsigned long *p; | |
4019 | int l; | |
4020 | if (!v) | |
4021 | return 1; | |
4022 | l = n[1]; | |
4023 | p = n + 2; | |
4024 | while (l) { | |
4025 | int i = l/2; | |
4026 | unsigned long *q = p + 2 * i; | |
4027 | if (*q == v) { | |
4028 | q[1]++; | |
4029 | return 1; | |
4030 | } | |
4031 | if (*q > v) { | |
4032 | l = i; | |
4033 | } else { | |
4034 | p = q + 2; | |
4035 | l -= i + 1; | |
4036 | } | |
4037 | } | |
4038 | if (++n[1] == n[0]) | |
4039 | return 0; | |
4040 | memmove(p + 2, p, n[1] * 2 * sizeof(unsigned long) - ((void *)p - (void *)n)); | |
4041 | p[0] = v; | |
4042 | p[1] = 1; | |
4043 | return 1; | |
4044 | } | |
4045 | ||
4046 | static void handle_slab(unsigned long *n, struct kmem_cache *c, struct slab *s) | |
4047 | { | |
4048 | void *p; | |
4049 | int i; | |
4050 | if (n[0] == n[1]) | |
4051 | return; | |
4052 | for (i = 0, p = s->s_mem; i < c->num; i++, p += c->buffer_size) { | |
4053 | if (slab_bufctl(s)[i] != BUFCTL_ACTIVE) | |
4054 | continue; | |
4055 | if (!add_caller(n, (unsigned long)*dbg_userword(c, p))) | |
4056 | return; | |
4057 | } | |
4058 | } | |
4059 | ||
4060 | static void show_symbol(struct seq_file *m, unsigned long address) | |
4061 | { | |
4062 | #ifdef CONFIG_KALLSYMS | |
4063 | char *modname; | |
4064 | const char *name; | |
4065 | unsigned long offset, size; | |
4066 | char namebuf[KSYM_NAME_LEN+1]; | |
4067 | ||
4068 | name = kallsyms_lookup(address, &size, &offset, &modname, namebuf); | |
4069 | ||
4070 | if (name) { | |
4071 | seq_printf(m, "%s+%#lx/%#lx", name, offset, size); | |
4072 | if (modname) | |
4073 | seq_printf(m, " [%s]", modname); | |
4074 | return; | |
4075 | } | |
4076 | #endif | |
4077 | seq_printf(m, "%p", (void *)address); | |
4078 | } | |
4079 | ||
4080 | static int leaks_show(struct seq_file *m, void *p) | |
4081 | { | |
4082 | struct kmem_cache *cachep = p; | |
4083 | struct list_head *q; | |
4084 | struct slab *slabp; | |
4085 | struct kmem_list3 *l3; | |
4086 | const char *name; | |
4087 | unsigned long *n = m->private; | |
4088 | int node; | |
4089 | int i; | |
4090 | ||
4091 | if (!(cachep->flags & SLAB_STORE_USER)) | |
4092 | return 0; | |
4093 | if (!(cachep->flags & SLAB_RED_ZONE)) | |
4094 | return 0; | |
4095 | ||
4096 | /* OK, we can do it */ | |
4097 | ||
4098 | n[1] = 0; | |
4099 | ||
4100 | for_each_online_node(node) { | |
4101 | l3 = cachep->nodelists[node]; | |
4102 | if (!l3) | |
4103 | continue; | |
4104 | ||
4105 | check_irq_on(); | |
4106 | spin_lock_irq(&l3->list_lock); | |
4107 | ||
4108 | list_for_each(q, &l3->slabs_full) { | |
4109 | slabp = list_entry(q, struct slab, list); | |
4110 | handle_slab(n, cachep, slabp); | |
4111 | } | |
4112 | list_for_each(q, &l3->slabs_partial) { | |
4113 | slabp = list_entry(q, struct slab, list); | |
4114 | handle_slab(n, cachep, slabp); | |
4115 | } | |
4116 | spin_unlock_irq(&l3->list_lock); | |
4117 | } | |
4118 | name = cachep->name; | |
4119 | if (n[0] == n[1]) { | |
4120 | /* Increase the buffer size */ | |
4121 | mutex_unlock(&cache_chain_mutex); | |
4122 | m->private = kzalloc(n[0] * 4 * sizeof(unsigned long), GFP_KERNEL); | |
4123 | if (!m->private) { | |
4124 | /* Too bad, we are really out */ | |
4125 | m->private = n; | |
4126 | mutex_lock(&cache_chain_mutex); | |
4127 | return -ENOMEM; | |
4128 | } | |
4129 | *(unsigned long *)m->private = n[0] * 2; | |
4130 | kfree(n); | |
4131 | mutex_lock(&cache_chain_mutex); | |
4132 | /* Now make sure this entry will be retried */ | |
4133 | m->count = m->size; | |
4134 | return 0; | |
4135 | } | |
4136 | for (i = 0; i < n[1]; i++) { | |
4137 | seq_printf(m, "%s: %lu ", name, n[2*i+3]); | |
4138 | show_symbol(m, n[2*i+2]); | |
4139 | seq_putc(m, '\n'); | |
4140 | } | |
4141 | return 0; | |
4142 | } | |
4143 | ||
4144 | struct seq_operations slabstats_op = { | |
4145 | .start = leaks_start, | |
4146 | .next = s_next, | |
4147 | .stop = s_stop, | |
4148 | .show = leaks_show, | |
4149 | }; | |
4150 | #endif | |
1da177e4 LT |
4151 | #endif |
4152 | ||
00e145b6 MS |
4153 | /** |
4154 | * ksize - get the actual amount of memory allocated for a given object | |
4155 | * @objp: Pointer to the object | |
4156 | * | |
4157 | * kmalloc may internally round up allocations and return more memory | |
4158 | * than requested. ksize() can be used to determine the actual amount of | |
4159 | * memory allocated. The caller may use this additional memory, even though | |
4160 | * a smaller amount of memory was initially specified with the kmalloc call. | |
4161 | * The caller must guarantee that objp points to a valid object previously | |
4162 | * allocated with either kmalloc() or kmem_cache_alloc(). The object | |
4163 | * must not be freed during the duration of the call. | |
4164 | */ | |
1da177e4 LT |
4165 | unsigned int ksize(const void *objp) |
4166 | { | |
00e145b6 MS |
4167 | if (unlikely(objp == NULL)) |
4168 | return 0; | |
1da177e4 | 4169 | |
6ed5eb22 | 4170 | return obj_size(virt_to_cache(objp)); |
1da177e4 | 4171 | } |