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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> | |
97 | #include <linux/seq_file.h> | |
98 | #include <linux/notifier.h> | |
99 | #include <linux/kallsyms.h> | |
100 | #include <linux/cpu.h> | |
101 | #include <linux/sysctl.h> | |
102 | #include <linux/module.h> | |
103 | #include <linux/rcupdate.h> | |
543537bd | 104 | #include <linux/string.h> |
e498be7d | 105 | #include <linux/nodemask.h> |
dc85da15 | 106 | #include <linux/mempolicy.h> |
fc0abb14 | 107 | #include <linux/mutex.h> |
1da177e4 LT |
108 | |
109 | #include <asm/uaccess.h> | |
110 | #include <asm/cacheflush.h> | |
111 | #include <asm/tlbflush.h> | |
112 | #include <asm/page.h> | |
113 | ||
114 | /* | |
115 | * DEBUG - 1 for kmem_cache_create() to honour; SLAB_DEBUG_INITIAL, | |
116 | * SLAB_RED_ZONE & SLAB_POISON. | |
117 | * 0 for faster, smaller code (especially in the critical paths). | |
118 | * | |
119 | * STATS - 1 to collect stats for /proc/slabinfo. | |
120 | * 0 for faster, smaller code (especially in the critical paths). | |
121 | * | |
122 | * FORCED_DEBUG - 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible) | |
123 | */ | |
124 | ||
125 | #ifdef CONFIG_DEBUG_SLAB | |
126 | #define DEBUG 1 | |
127 | #define STATS 1 | |
128 | #define FORCED_DEBUG 1 | |
129 | #else | |
130 | #define DEBUG 0 | |
131 | #define STATS 0 | |
132 | #define FORCED_DEBUG 0 | |
133 | #endif | |
134 | ||
1da177e4 LT |
135 | /* Shouldn't this be in a header file somewhere? */ |
136 | #define BYTES_PER_WORD sizeof(void *) | |
137 | ||
138 | #ifndef cache_line_size | |
139 | #define cache_line_size() L1_CACHE_BYTES | |
140 | #endif | |
141 | ||
142 | #ifndef ARCH_KMALLOC_MINALIGN | |
143 | /* | |
144 | * Enforce a minimum alignment for the kmalloc caches. | |
145 | * Usually, the kmalloc caches are cache_line_size() aligned, except when | |
146 | * DEBUG and FORCED_DEBUG are enabled, then they are BYTES_PER_WORD aligned. | |
147 | * Some archs want to perform DMA into kmalloc caches and need a guaranteed | |
148 | * alignment larger than BYTES_PER_WORD. ARCH_KMALLOC_MINALIGN allows that. | |
149 | * Note that this flag disables some debug features. | |
150 | */ | |
151 | #define ARCH_KMALLOC_MINALIGN 0 | |
152 | #endif | |
153 | ||
154 | #ifndef ARCH_SLAB_MINALIGN | |
155 | /* | |
156 | * Enforce a minimum alignment for all caches. | |
157 | * Intended for archs that get misalignment faults even for BYTES_PER_WORD | |
158 | * aligned buffers. Includes ARCH_KMALLOC_MINALIGN. | |
159 | * If possible: Do not enable this flag for CONFIG_DEBUG_SLAB, it disables | |
160 | * some debug features. | |
161 | */ | |
162 | #define ARCH_SLAB_MINALIGN 0 | |
163 | #endif | |
164 | ||
165 | #ifndef ARCH_KMALLOC_FLAGS | |
166 | #define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN | |
167 | #endif | |
168 | ||
169 | /* Legal flag mask for kmem_cache_create(). */ | |
170 | #if DEBUG | |
171 | # define CREATE_MASK (SLAB_DEBUG_INITIAL | SLAB_RED_ZONE | \ | |
172 | SLAB_POISON | SLAB_HWCACHE_ALIGN | \ | |
173 | SLAB_NO_REAP | SLAB_CACHE_DMA | \ | |
174 | SLAB_MUST_HWCACHE_ALIGN | SLAB_STORE_USER | \ | |
175 | SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \ | |
176 | SLAB_DESTROY_BY_RCU) | |
177 | #else | |
178 | # define CREATE_MASK (SLAB_HWCACHE_ALIGN | SLAB_NO_REAP | \ | |
179 | SLAB_CACHE_DMA | SLAB_MUST_HWCACHE_ALIGN | \ | |
180 | SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \ | |
181 | SLAB_DESTROY_BY_RCU) | |
182 | #endif | |
183 | ||
184 | /* | |
185 | * kmem_bufctl_t: | |
186 | * | |
187 | * Bufctl's are used for linking objs within a slab | |
188 | * linked offsets. | |
189 | * | |
190 | * This implementation relies on "struct page" for locating the cache & | |
191 | * slab an object belongs to. | |
192 | * This allows the bufctl structure to be small (one int), but limits | |
193 | * the number of objects a slab (not a cache) can contain when off-slab | |
194 | * bufctls are used. The limit is the size of the largest general cache | |
195 | * that does not use off-slab slabs. | |
196 | * For 32bit archs with 4 kB pages, is this 56. | |
197 | * This is not serious, as it is only for large objects, when it is unwise | |
198 | * to have too many per slab. | |
199 | * Note: This limit can be raised by introducing a general cache whose size | |
200 | * is less than 512 (PAGE_SIZE<<3), but greater than 256. | |
201 | */ | |
202 | ||
fa5b08d5 | 203 | typedef unsigned int kmem_bufctl_t; |
1da177e4 LT |
204 | #define BUFCTL_END (((kmem_bufctl_t)(~0U))-0) |
205 | #define BUFCTL_FREE (((kmem_bufctl_t)(~0U))-1) | |
206 | #define SLAB_LIMIT (((kmem_bufctl_t)(~0U))-2) | |
207 | ||
208 | /* Max number of objs-per-slab for caches which use off-slab slabs. | |
209 | * Needed to avoid a possible looping condition in cache_grow(). | |
210 | */ | |
211 | static unsigned long offslab_limit; | |
212 | ||
213 | /* | |
214 | * struct slab | |
215 | * | |
216 | * Manages the objs in a slab. Placed either at the beginning of mem allocated | |
217 | * for a slab, or allocated from an general cache. | |
218 | * Slabs are chained into three list: fully used, partial, fully free slabs. | |
219 | */ | |
220 | struct slab { | |
b28a02de PE |
221 | struct list_head list; |
222 | unsigned long colouroff; | |
223 | void *s_mem; /* including colour offset */ | |
224 | unsigned int inuse; /* num of objs active in slab */ | |
225 | kmem_bufctl_t free; | |
226 | unsigned short nodeid; | |
1da177e4 LT |
227 | }; |
228 | ||
229 | /* | |
230 | * struct slab_rcu | |
231 | * | |
232 | * slab_destroy on a SLAB_DESTROY_BY_RCU cache uses this structure to | |
233 | * arrange for kmem_freepages to be called via RCU. This is useful if | |
234 | * we need to approach a kernel structure obliquely, from its address | |
235 | * obtained without the usual locking. We can lock the structure to | |
236 | * stabilize it and check it's still at the given address, only if we | |
237 | * can be sure that the memory has not been meanwhile reused for some | |
238 | * other kind of object (which our subsystem's lock might corrupt). | |
239 | * | |
240 | * rcu_read_lock before reading the address, then rcu_read_unlock after | |
241 | * taking the spinlock within the structure expected at that address. | |
242 | * | |
243 | * We assume struct slab_rcu can overlay struct slab when destroying. | |
244 | */ | |
245 | struct slab_rcu { | |
b28a02de | 246 | struct rcu_head head; |
343e0d7a | 247 | struct kmem_cache *cachep; |
b28a02de | 248 | void *addr; |
1da177e4 LT |
249 | }; |
250 | ||
251 | /* | |
252 | * struct array_cache | |
253 | * | |
1da177e4 LT |
254 | * Purpose: |
255 | * - LIFO ordering, to hand out cache-warm objects from _alloc | |
256 | * - reduce the number of linked list operations | |
257 | * - reduce spinlock operations | |
258 | * | |
259 | * The limit is stored in the per-cpu structure to reduce the data cache | |
260 | * footprint. | |
261 | * | |
262 | */ | |
263 | struct array_cache { | |
264 | unsigned int avail; | |
265 | unsigned int limit; | |
266 | unsigned int batchcount; | |
267 | unsigned int touched; | |
e498be7d | 268 | spinlock_t lock; |
a737b3e2 AM |
269 | void *entry[0]; /* |
270 | * Must have this definition in here for the proper | |
271 | * alignment of array_cache. Also simplifies accessing | |
272 | * the entries. | |
273 | * [0] is for gcc 2.95. It should really be []. | |
274 | */ | |
1da177e4 LT |
275 | }; |
276 | ||
a737b3e2 AM |
277 | /* |
278 | * bootstrap: The caches do not work without cpuarrays anymore, but the | |
279 | * cpuarrays are allocated from the generic caches... | |
1da177e4 LT |
280 | */ |
281 | #define BOOT_CPUCACHE_ENTRIES 1 | |
282 | struct arraycache_init { | |
283 | struct array_cache cache; | |
b28a02de | 284 | void *entries[BOOT_CPUCACHE_ENTRIES]; |
1da177e4 LT |
285 | }; |
286 | ||
287 | /* | |
e498be7d | 288 | * The slab lists for all objects. |
1da177e4 LT |
289 | */ |
290 | struct kmem_list3 { | |
b28a02de PE |
291 | struct list_head slabs_partial; /* partial list first, better asm code */ |
292 | struct list_head slabs_full; | |
293 | struct list_head slabs_free; | |
294 | unsigned long free_objects; | |
295 | unsigned long next_reap; | |
296 | int free_touched; | |
297 | unsigned int free_limit; | |
2e1217cf | 298 | unsigned int colour_next; /* Per-node cache coloring */ |
b28a02de PE |
299 | spinlock_t list_lock; |
300 | struct array_cache *shared; /* shared per node */ | |
301 | struct array_cache **alien; /* on other nodes */ | |
1da177e4 LT |
302 | }; |
303 | ||
e498be7d CL |
304 | /* |
305 | * Need this for bootstrapping a per node allocator. | |
306 | */ | |
307 | #define NUM_INIT_LISTS (2 * MAX_NUMNODES + 1) | |
308 | struct kmem_list3 __initdata initkmem_list3[NUM_INIT_LISTS]; | |
309 | #define CACHE_CACHE 0 | |
310 | #define SIZE_AC 1 | |
311 | #define SIZE_L3 (1 + MAX_NUMNODES) | |
312 | ||
313 | /* | |
a737b3e2 AM |
314 | * This function must be completely optimized away if a constant is passed to |
315 | * it. Mostly the same as what is in linux/slab.h except it returns an index. | |
e498be7d | 316 | */ |
7243cc05 | 317 | static __always_inline int index_of(const size_t size) |
e498be7d | 318 | { |
5ec8a847 SR |
319 | extern void __bad_size(void); |
320 | ||
e498be7d CL |
321 | if (__builtin_constant_p(size)) { |
322 | int i = 0; | |
323 | ||
324 | #define CACHE(x) \ | |
325 | if (size <=x) \ | |
326 | return i; \ | |
327 | else \ | |
328 | i++; | |
329 | #include "linux/kmalloc_sizes.h" | |
330 | #undef CACHE | |
5ec8a847 | 331 | __bad_size(); |
7243cc05 | 332 | } else |
5ec8a847 | 333 | __bad_size(); |
e498be7d CL |
334 | return 0; |
335 | } | |
336 | ||
337 | #define INDEX_AC index_of(sizeof(struct arraycache_init)) | |
338 | #define INDEX_L3 index_of(sizeof(struct kmem_list3)) | |
1da177e4 | 339 | |
5295a74c | 340 | static void kmem_list3_init(struct kmem_list3 *parent) |
e498be7d CL |
341 | { |
342 | INIT_LIST_HEAD(&parent->slabs_full); | |
343 | INIT_LIST_HEAD(&parent->slabs_partial); | |
344 | INIT_LIST_HEAD(&parent->slabs_free); | |
345 | parent->shared = NULL; | |
346 | parent->alien = NULL; | |
2e1217cf | 347 | parent->colour_next = 0; |
e498be7d CL |
348 | spin_lock_init(&parent->list_lock); |
349 | parent->free_objects = 0; | |
350 | parent->free_touched = 0; | |
351 | } | |
352 | ||
a737b3e2 AM |
353 | #define MAKE_LIST(cachep, listp, slab, nodeid) \ |
354 | do { \ | |
355 | INIT_LIST_HEAD(listp); \ | |
356 | list_splice(&(cachep->nodelists[nodeid]->slab), listp); \ | |
e498be7d CL |
357 | } while (0) |
358 | ||
a737b3e2 AM |
359 | #define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ |
360 | do { \ | |
e498be7d CL |
361 | MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \ |
362 | MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \ | |
363 | MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \ | |
364 | } while (0) | |
1da177e4 LT |
365 | |
366 | /* | |
343e0d7a | 367 | * struct kmem_cache |
1da177e4 LT |
368 | * |
369 | * manages a cache. | |
370 | */ | |
b28a02de | 371 | |
2109a2d1 | 372 | struct kmem_cache { |
1da177e4 | 373 | /* 1) per-cpu data, touched during every alloc/free */ |
b28a02de | 374 | struct array_cache *array[NR_CPUS]; |
b5d8ca7c | 375 | /* 2) Cache tunables. Protected by cache_chain_mutex */ |
b28a02de PE |
376 | unsigned int batchcount; |
377 | unsigned int limit; | |
378 | unsigned int shared; | |
b5d8ca7c | 379 | |
3dafccf2 | 380 | unsigned int buffer_size; |
b5d8ca7c | 381 | /* 3) touched by every alloc & free from the backend */ |
b28a02de | 382 | struct kmem_list3 *nodelists[MAX_NUMNODES]; |
b5d8ca7c | 383 | |
a737b3e2 AM |
384 | unsigned int flags; /* constant flags */ |
385 | unsigned int num; /* # of objs per slab */ | |
1da177e4 | 386 | |
b5d8ca7c | 387 | /* 4) cache_grow/shrink */ |
1da177e4 | 388 | /* order of pgs per slab (2^n) */ |
b28a02de | 389 | unsigned int gfporder; |
1da177e4 LT |
390 | |
391 | /* force GFP flags, e.g. GFP_DMA */ | |
b28a02de | 392 | gfp_t gfpflags; |
1da177e4 | 393 | |
a737b3e2 | 394 | size_t colour; /* cache colouring range */ |
b28a02de | 395 | unsigned int colour_off; /* colour offset */ |
343e0d7a | 396 | struct kmem_cache *slabp_cache; |
b28a02de | 397 | unsigned int slab_size; |
a737b3e2 | 398 | unsigned int dflags; /* dynamic flags */ |
1da177e4 LT |
399 | |
400 | /* constructor func */ | |
343e0d7a | 401 | void (*ctor) (void *, struct kmem_cache *, unsigned long); |
1da177e4 LT |
402 | |
403 | /* de-constructor func */ | |
343e0d7a | 404 | void (*dtor) (void *, struct kmem_cache *, unsigned long); |
1da177e4 | 405 | |
b5d8ca7c | 406 | /* 5) cache creation/removal */ |
b28a02de PE |
407 | const char *name; |
408 | struct list_head next; | |
1da177e4 | 409 | |
b5d8ca7c | 410 | /* 6) statistics */ |
1da177e4 | 411 | #if STATS |
b28a02de PE |
412 | unsigned long num_active; |
413 | unsigned long num_allocations; | |
414 | unsigned long high_mark; | |
415 | unsigned long grown; | |
416 | unsigned long reaped; | |
417 | unsigned long errors; | |
418 | unsigned long max_freeable; | |
419 | unsigned long node_allocs; | |
420 | unsigned long node_frees; | |
421 | atomic_t allochit; | |
422 | atomic_t allocmiss; | |
423 | atomic_t freehit; | |
424 | atomic_t freemiss; | |
1da177e4 LT |
425 | #endif |
426 | #if DEBUG | |
3dafccf2 MS |
427 | /* |
428 | * If debugging is enabled, then the allocator can add additional | |
429 | * fields and/or padding to every object. buffer_size contains the total | |
430 | * object size including these internal fields, the following two | |
431 | * variables contain the offset to the user object and its size. | |
432 | */ | |
433 | int obj_offset; | |
434 | int obj_size; | |
1da177e4 LT |
435 | #endif |
436 | }; | |
437 | ||
438 | #define CFLGS_OFF_SLAB (0x80000000UL) | |
439 | #define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) | |
440 | ||
441 | #define BATCHREFILL_LIMIT 16 | |
a737b3e2 AM |
442 | /* |
443 | * Optimization question: fewer reaps means less probability for unnessary | |
444 | * cpucache drain/refill cycles. | |
1da177e4 | 445 | * |
dc6f3f27 | 446 | * OTOH the cpuarrays can contain lots of objects, |
1da177e4 LT |
447 | * which could lock up otherwise freeable slabs. |
448 | */ | |
449 | #define REAPTIMEOUT_CPUC (2*HZ) | |
450 | #define REAPTIMEOUT_LIST3 (4*HZ) | |
451 | ||
452 | #if STATS | |
453 | #define STATS_INC_ACTIVE(x) ((x)->num_active++) | |
454 | #define STATS_DEC_ACTIVE(x) ((x)->num_active--) | |
455 | #define STATS_INC_ALLOCED(x) ((x)->num_allocations++) | |
456 | #define STATS_INC_GROWN(x) ((x)->grown++) | |
457 | #define STATS_INC_REAPED(x) ((x)->reaped++) | |
a737b3e2 AM |
458 | #define STATS_SET_HIGH(x) \ |
459 | do { \ | |
460 | if ((x)->num_active > (x)->high_mark) \ | |
461 | (x)->high_mark = (x)->num_active; \ | |
462 | } while (0) | |
1da177e4 LT |
463 | #define STATS_INC_ERR(x) ((x)->errors++) |
464 | #define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) | |
e498be7d | 465 | #define STATS_INC_NODEFREES(x) ((x)->node_frees++) |
a737b3e2 AM |
466 | #define STATS_SET_FREEABLE(x, i) \ |
467 | do { \ | |
468 | if ((x)->max_freeable < i) \ | |
469 | (x)->max_freeable = i; \ | |
470 | } while (0) | |
1da177e4 LT |
471 | #define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) |
472 | #define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) | |
473 | #define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) | |
474 | #define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) | |
475 | #else | |
476 | #define STATS_INC_ACTIVE(x) do { } while (0) | |
477 | #define STATS_DEC_ACTIVE(x) do { } while (0) | |
478 | #define STATS_INC_ALLOCED(x) do { } while (0) | |
479 | #define STATS_INC_GROWN(x) do { } while (0) | |
480 | #define STATS_INC_REAPED(x) do { } while (0) | |
481 | #define STATS_SET_HIGH(x) do { } while (0) | |
482 | #define STATS_INC_ERR(x) do { } while (0) | |
483 | #define STATS_INC_NODEALLOCS(x) do { } while (0) | |
e498be7d | 484 | #define STATS_INC_NODEFREES(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 | { | |
593 | return (struct kmem_cache *)page->lru.next; | |
594 | } | |
595 | ||
596 | static inline void page_set_slab(struct page *page, struct slab *slab) | |
597 | { | |
598 | page->lru.prev = (struct list_head *)slab; | |
599 | } | |
600 | ||
601 | static inline struct slab *page_get_slab(struct page *page) | |
602 | { | |
603 | return (struct slab *)page->lru.prev; | |
604 | } | |
1da177e4 | 605 | |
6ed5eb22 PE |
606 | static inline struct kmem_cache *virt_to_cache(const void *obj) |
607 | { | |
608 | struct page *page = virt_to_page(obj); | |
609 | return page_get_cache(page); | |
610 | } | |
611 | ||
612 | static inline struct slab *virt_to_slab(const void *obj) | |
613 | { | |
614 | struct page *page = virt_to_page(obj); | |
615 | return page_get_slab(page); | |
616 | } | |
617 | ||
8fea4e96 PE |
618 | static inline void *index_to_obj(struct kmem_cache *cache, struct slab *slab, |
619 | unsigned int idx) | |
620 | { | |
621 | return slab->s_mem + cache->buffer_size * idx; | |
622 | } | |
623 | ||
624 | static inline unsigned int obj_to_index(struct kmem_cache *cache, | |
625 | struct slab *slab, void *obj) | |
626 | { | |
627 | return (unsigned)(obj - slab->s_mem) / cache->buffer_size; | |
628 | } | |
629 | ||
a737b3e2 AM |
630 | /* |
631 | * These are the default caches for kmalloc. Custom caches can have other sizes. | |
632 | */ | |
1da177e4 LT |
633 | struct cache_sizes malloc_sizes[] = { |
634 | #define CACHE(x) { .cs_size = (x) }, | |
635 | #include <linux/kmalloc_sizes.h> | |
636 | CACHE(ULONG_MAX) | |
637 | #undef CACHE | |
638 | }; | |
639 | EXPORT_SYMBOL(malloc_sizes); | |
640 | ||
641 | /* Must match cache_sizes above. Out of line to keep cache footprint low. */ | |
642 | struct cache_names { | |
643 | char *name; | |
644 | char *name_dma; | |
645 | }; | |
646 | ||
647 | static struct cache_names __initdata cache_names[] = { | |
648 | #define CACHE(x) { .name = "size-" #x, .name_dma = "size-" #x "(DMA)" }, | |
649 | #include <linux/kmalloc_sizes.h> | |
b28a02de | 650 | {NULL,} |
1da177e4 LT |
651 | #undef CACHE |
652 | }; | |
653 | ||
654 | static struct arraycache_init initarray_cache __initdata = | |
b28a02de | 655 | { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; |
1da177e4 | 656 | static struct arraycache_init initarray_generic = |
b28a02de | 657 | { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; |
1da177e4 LT |
658 | |
659 | /* internal cache of cache description objs */ | |
343e0d7a | 660 | static struct kmem_cache cache_cache = { |
b28a02de PE |
661 | .batchcount = 1, |
662 | .limit = BOOT_CPUCACHE_ENTRIES, | |
663 | .shared = 1, | |
343e0d7a | 664 | .buffer_size = sizeof(struct kmem_cache), |
b28a02de | 665 | .flags = SLAB_NO_REAP, |
b28a02de | 666 | .name = "kmem_cache", |
1da177e4 | 667 | #if DEBUG |
343e0d7a | 668 | .obj_size = sizeof(struct kmem_cache), |
1da177e4 LT |
669 | #endif |
670 | }; | |
671 | ||
672 | /* Guard access to the cache-chain. */ | |
fc0abb14 | 673 | static DEFINE_MUTEX(cache_chain_mutex); |
1da177e4 LT |
674 | static struct list_head cache_chain; |
675 | ||
676 | /* | |
a737b3e2 AM |
677 | * vm_enough_memory() looks at this to determine how many slab-allocated pages |
678 | * are possibly freeable under pressure | |
1da177e4 LT |
679 | * |
680 | * SLAB_RECLAIM_ACCOUNT turns this on per-slab | |
681 | */ | |
682 | atomic_t slab_reclaim_pages; | |
1da177e4 LT |
683 | |
684 | /* | |
685 | * chicken and egg problem: delay the per-cpu array allocation | |
686 | * until the general caches are up. | |
687 | */ | |
688 | static enum { | |
689 | NONE, | |
e498be7d CL |
690 | PARTIAL_AC, |
691 | PARTIAL_L3, | |
1da177e4 LT |
692 | FULL |
693 | } g_cpucache_up; | |
694 | ||
695 | static DEFINE_PER_CPU(struct work_struct, reap_work); | |
696 | ||
a737b3e2 AM |
697 | static void free_block(struct kmem_cache *cachep, void **objpp, int len, |
698 | int node); | |
343e0d7a | 699 | static void enable_cpucache(struct kmem_cache *cachep); |
b28a02de | 700 | static void cache_reap(void *unused); |
343e0d7a | 701 | static int __node_shrink(struct kmem_cache *cachep, int node); |
1da177e4 | 702 | |
343e0d7a | 703 | static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) |
1da177e4 LT |
704 | { |
705 | return cachep->array[smp_processor_id()]; | |
706 | } | |
707 | ||
a737b3e2 AM |
708 | static inline struct kmem_cache *__find_general_cachep(size_t size, |
709 | gfp_t gfpflags) | |
1da177e4 LT |
710 | { |
711 | struct cache_sizes *csizep = malloc_sizes; | |
712 | ||
713 | #if DEBUG | |
714 | /* This happens if someone tries to call | |
b28a02de PE |
715 | * kmem_cache_create(), or __kmalloc(), before |
716 | * the generic caches are initialized. | |
717 | */ | |
c7e43c78 | 718 | BUG_ON(malloc_sizes[INDEX_AC].cs_cachep == NULL); |
1da177e4 LT |
719 | #endif |
720 | while (size > csizep->cs_size) | |
721 | csizep++; | |
722 | ||
723 | /* | |
0abf40c1 | 724 | * Really subtle: The last entry with cs->cs_size==ULONG_MAX |
1da177e4 LT |
725 | * has cs_{dma,}cachep==NULL. Thus no special case |
726 | * for large kmalloc calls required. | |
727 | */ | |
728 | if (unlikely(gfpflags & GFP_DMA)) | |
729 | return csizep->cs_dmacachep; | |
730 | return csizep->cs_cachep; | |
731 | } | |
732 | ||
343e0d7a | 733 | struct kmem_cache *kmem_find_general_cachep(size_t size, gfp_t gfpflags) |
97e2bde4 MS |
734 | { |
735 | return __find_general_cachep(size, gfpflags); | |
736 | } | |
737 | EXPORT_SYMBOL(kmem_find_general_cachep); | |
738 | ||
fbaccacf | 739 | static size_t slab_mgmt_size(size_t nr_objs, size_t align) |
1da177e4 | 740 | { |
fbaccacf SR |
741 | return ALIGN(sizeof(struct slab)+nr_objs*sizeof(kmem_bufctl_t), align); |
742 | } | |
1da177e4 | 743 | |
a737b3e2 AM |
744 | /* |
745 | * Calculate the number of objects and left-over bytes for a given buffer size. | |
746 | */ | |
fbaccacf SR |
747 | static void cache_estimate(unsigned long gfporder, size_t buffer_size, |
748 | size_t align, int flags, size_t *left_over, | |
749 | unsigned int *num) | |
750 | { | |
751 | int nr_objs; | |
752 | size_t mgmt_size; | |
753 | size_t slab_size = PAGE_SIZE << gfporder; | |
1da177e4 | 754 | |
fbaccacf SR |
755 | /* |
756 | * The slab management structure can be either off the slab or | |
757 | * on it. For the latter case, the memory allocated for a | |
758 | * slab is used for: | |
759 | * | |
760 | * - The struct slab | |
761 | * - One kmem_bufctl_t for each object | |
762 | * - Padding to respect alignment of @align | |
763 | * - @buffer_size bytes for each object | |
764 | * | |
765 | * If the slab management structure is off the slab, then the | |
766 | * alignment will already be calculated into the size. Because | |
767 | * the slabs are all pages aligned, the objects will be at the | |
768 | * correct alignment when allocated. | |
769 | */ | |
770 | if (flags & CFLGS_OFF_SLAB) { | |
771 | mgmt_size = 0; | |
772 | nr_objs = slab_size / buffer_size; | |
773 | ||
774 | if (nr_objs > SLAB_LIMIT) | |
775 | nr_objs = SLAB_LIMIT; | |
776 | } else { | |
777 | /* | |
778 | * Ignore padding for the initial guess. The padding | |
779 | * is at most @align-1 bytes, and @buffer_size is at | |
780 | * least @align. In the worst case, this result will | |
781 | * be one greater than the number of objects that fit | |
782 | * into the memory allocation when taking the padding | |
783 | * into account. | |
784 | */ | |
785 | nr_objs = (slab_size - sizeof(struct slab)) / | |
786 | (buffer_size + sizeof(kmem_bufctl_t)); | |
787 | ||
788 | /* | |
789 | * This calculated number will be either the right | |
790 | * amount, or one greater than what we want. | |
791 | */ | |
792 | if (slab_mgmt_size(nr_objs, align) + nr_objs*buffer_size | |
793 | > slab_size) | |
794 | nr_objs--; | |
795 | ||
796 | if (nr_objs > SLAB_LIMIT) | |
797 | nr_objs = SLAB_LIMIT; | |
798 | ||
799 | mgmt_size = slab_mgmt_size(nr_objs, align); | |
800 | } | |
801 | *num = nr_objs; | |
802 | *left_over = slab_size - nr_objs*buffer_size - mgmt_size; | |
1da177e4 LT |
803 | } |
804 | ||
805 | #define slab_error(cachep, msg) __slab_error(__FUNCTION__, cachep, msg) | |
806 | ||
a737b3e2 AM |
807 | static void __slab_error(const char *function, struct kmem_cache *cachep, |
808 | char *msg) | |
1da177e4 LT |
809 | { |
810 | printk(KERN_ERR "slab error in %s(): cache `%s': %s\n", | |
b28a02de | 811 | function, cachep->name, msg); |
1da177e4 LT |
812 | dump_stack(); |
813 | } | |
814 | ||
8fce4d8e CL |
815 | #ifdef CONFIG_NUMA |
816 | /* | |
817 | * Special reaping functions for NUMA systems called from cache_reap(). | |
818 | * These take care of doing round robin flushing of alien caches (containing | |
819 | * objects freed on different nodes from which they were allocated) and the | |
820 | * flushing of remote pcps by calling drain_node_pages. | |
821 | */ | |
822 | static DEFINE_PER_CPU(unsigned long, reap_node); | |
823 | ||
824 | static void init_reap_node(int cpu) | |
825 | { | |
826 | int node; | |
827 | ||
828 | node = next_node(cpu_to_node(cpu), node_online_map); | |
829 | if (node == MAX_NUMNODES) | |
830 | node = 0; | |
831 | ||
832 | __get_cpu_var(reap_node) = node; | |
833 | } | |
834 | ||
835 | static void next_reap_node(void) | |
836 | { | |
837 | int node = __get_cpu_var(reap_node); | |
838 | ||
839 | /* | |
840 | * Also drain per cpu pages on remote zones | |
841 | */ | |
842 | if (node != numa_node_id()) | |
843 | drain_node_pages(node); | |
844 | ||
845 | node = next_node(node, node_online_map); | |
846 | if (unlikely(node >= MAX_NUMNODES)) | |
847 | node = first_node(node_online_map); | |
848 | __get_cpu_var(reap_node) = node; | |
849 | } | |
850 | ||
851 | #else | |
852 | #define init_reap_node(cpu) do { } while (0) | |
853 | #define next_reap_node(void) do { } while (0) | |
854 | #endif | |
855 | ||
1da177e4 LT |
856 | /* |
857 | * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz | |
858 | * via the workqueue/eventd. | |
859 | * Add the CPU number into the expiration time to minimize the possibility of | |
860 | * the CPUs getting into lockstep and contending for the global cache chain | |
861 | * lock. | |
862 | */ | |
863 | static void __devinit start_cpu_timer(int cpu) | |
864 | { | |
865 | struct work_struct *reap_work = &per_cpu(reap_work, cpu); | |
866 | ||
867 | /* | |
868 | * When this gets called from do_initcalls via cpucache_init(), | |
869 | * init_workqueues() has already run, so keventd will be setup | |
870 | * at that time. | |
871 | */ | |
872 | if (keventd_up() && reap_work->func == NULL) { | |
8fce4d8e | 873 | init_reap_node(cpu); |
1da177e4 LT |
874 | INIT_WORK(reap_work, cache_reap, NULL); |
875 | schedule_delayed_work_on(cpu, reap_work, HZ + 3 * cpu); | |
876 | } | |
877 | } | |
878 | ||
e498be7d | 879 | static struct array_cache *alloc_arraycache(int node, int entries, |
b28a02de | 880 | int batchcount) |
1da177e4 | 881 | { |
b28a02de | 882 | int memsize = sizeof(void *) * entries + sizeof(struct array_cache); |
1da177e4 LT |
883 | struct array_cache *nc = NULL; |
884 | ||
e498be7d | 885 | nc = kmalloc_node(memsize, GFP_KERNEL, node); |
1da177e4 LT |
886 | if (nc) { |
887 | nc->avail = 0; | |
888 | nc->limit = entries; | |
889 | nc->batchcount = batchcount; | |
890 | nc->touched = 0; | |
e498be7d | 891 | spin_lock_init(&nc->lock); |
1da177e4 LT |
892 | } |
893 | return nc; | |
894 | } | |
895 | ||
e498be7d | 896 | #ifdef CONFIG_NUMA |
343e0d7a | 897 | static void *__cache_alloc_node(struct kmem_cache *, gfp_t, int); |
dc85da15 | 898 | |
5295a74c | 899 | static struct array_cache **alloc_alien_cache(int node, int limit) |
e498be7d CL |
900 | { |
901 | struct array_cache **ac_ptr; | |
b28a02de | 902 | int memsize = sizeof(void *) * MAX_NUMNODES; |
e498be7d CL |
903 | int i; |
904 | ||
905 | if (limit > 1) | |
906 | limit = 12; | |
907 | ac_ptr = kmalloc_node(memsize, GFP_KERNEL, node); | |
908 | if (ac_ptr) { | |
909 | for_each_node(i) { | |
910 | if (i == node || !node_online(i)) { | |
911 | ac_ptr[i] = NULL; | |
912 | continue; | |
913 | } | |
914 | ac_ptr[i] = alloc_arraycache(node, limit, 0xbaadf00d); | |
915 | if (!ac_ptr[i]) { | |
b28a02de | 916 | for (i--; i <= 0; i--) |
e498be7d CL |
917 | kfree(ac_ptr[i]); |
918 | kfree(ac_ptr); | |
919 | return NULL; | |
920 | } | |
921 | } | |
922 | } | |
923 | return ac_ptr; | |
924 | } | |
925 | ||
5295a74c | 926 | static void free_alien_cache(struct array_cache **ac_ptr) |
e498be7d CL |
927 | { |
928 | int i; | |
929 | ||
930 | if (!ac_ptr) | |
931 | return; | |
e498be7d | 932 | for_each_node(i) |
b28a02de | 933 | kfree(ac_ptr[i]); |
e498be7d CL |
934 | kfree(ac_ptr); |
935 | } | |
936 | ||
343e0d7a | 937 | static void __drain_alien_cache(struct kmem_cache *cachep, |
5295a74c | 938 | struct array_cache *ac, int node) |
e498be7d CL |
939 | { |
940 | struct kmem_list3 *rl3 = cachep->nodelists[node]; | |
941 | ||
942 | if (ac->avail) { | |
943 | spin_lock(&rl3->list_lock); | |
ff69416e | 944 | free_block(cachep, ac->entry, ac->avail, node); |
e498be7d CL |
945 | ac->avail = 0; |
946 | spin_unlock(&rl3->list_lock); | |
947 | } | |
948 | } | |
949 | ||
8fce4d8e CL |
950 | /* |
951 | * Called from cache_reap() to regularly drain alien caches round robin. | |
952 | */ | |
953 | static void reap_alien(struct kmem_cache *cachep, struct kmem_list3 *l3) | |
954 | { | |
955 | int node = __get_cpu_var(reap_node); | |
956 | ||
957 | if (l3->alien) { | |
958 | struct array_cache *ac = l3->alien[node]; | |
959 | if (ac && ac->avail) { | |
960 | spin_lock_irq(&ac->lock); | |
961 | __drain_alien_cache(cachep, ac, node); | |
962 | spin_unlock_irq(&ac->lock); | |
963 | } | |
964 | } | |
965 | } | |
966 | ||
a737b3e2 AM |
967 | static void drain_alien_cache(struct kmem_cache *cachep, |
968 | struct array_cache **alien) | |
e498be7d | 969 | { |
b28a02de | 970 | int i = 0; |
e498be7d CL |
971 | struct array_cache *ac; |
972 | unsigned long flags; | |
973 | ||
974 | for_each_online_node(i) { | |
4484ebf1 | 975 | ac = alien[i]; |
e498be7d CL |
976 | if (ac) { |
977 | spin_lock_irqsave(&ac->lock, flags); | |
978 | __drain_alien_cache(cachep, ac, i); | |
979 | spin_unlock_irqrestore(&ac->lock, flags); | |
980 | } | |
981 | } | |
982 | } | |
983 | #else | |
7a21ef6f | 984 | |
4484ebf1 | 985 | #define drain_alien_cache(cachep, alien) do { } while (0) |
8fce4d8e | 986 | #define reap_alien(cachep, l3) do { } while (0) |
4484ebf1 | 987 | |
7a21ef6f LT |
988 | static inline struct array_cache **alloc_alien_cache(int node, int limit) |
989 | { | |
990 | return (struct array_cache **) 0x01020304ul; | |
991 | } | |
992 | ||
4484ebf1 RT |
993 | static inline void free_alien_cache(struct array_cache **ac_ptr) |
994 | { | |
995 | } | |
7a21ef6f | 996 | |
e498be7d CL |
997 | #endif |
998 | ||
1da177e4 | 999 | static int __devinit cpuup_callback(struct notifier_block *nfb, |
b28a02de | 1000 | unsigned long action, void *hcpu) |
1da177e4 LT |
1001 | { |
1002 | long cpu = (long)hcpu; | |
343e0d7a | 1003 | struct kmem_cache *cachep; |
e498be7d CL |
1004 | struct kmem_list3 *l3 = NULL; |
1005 | int node = cpu_to_node(cpu); | |
1006 | int memsize = sizeof(struct kmem_list3); | |
1da177e4 LT |
1007 | |
1008 | switch (action) { | |
1009 | case CPU_UP_PREPARE: | |
fc0abb14 | 1010 | mutex_lock(&cache_chain_mutex); |
a737b3e2 AM |
1011 | /* |
1012 | * We need to do this right in the beginning since | |
e498be7d CL |
1013 | * alloc_arraycache's are going to use this list. |
1014 | * kmalloc_node allows us to add the slab to the right | |
1015 | * kmem_list3 and not this cpu's kmem_list3 | |
1016 | */ | |
1017 | ||
1da177e4 | 1018 | list_for_each_entry(cachep, &cache_chain, next) { |
a737b3e2 AM |
1019 | /* |
1020 | * Set up the size64 kmemlist for cpu before we can | |
e498be7d CL |
1021 | * begin anything. Make sure some other cpu on this |
1022 | * node has not already allocated this | |
1023 | */ | |
1024 | if (!cachep->nodelists[node]) { | |
a737b3e2 AM |
1025 | l3 = kmalloc_node(memsize, GFP_KERNEL, node); |
1026 | if (!l3) | |
e498be7d CL |
1027 | goto bad; |
1028 | kmem_list3_init(l3); | |
1029 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + | |
b28a02de | 1030 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
e498be7d | 1031 | |
4484ebf1 RT |
1032 | /* |
1033 | * The l3s don't come and go as CPUs come and | |
1034 | * go. cache_chain_mutex is sufficient | |
1035 | * protection here. | |
1036 | */ | |
e498be7d CL |
1037 | cachep->nodelists[node] = l3; |
1038 | } | |
1da177e4 | 1039 | |
e498be7d CL |
1040 | spin_lock_irq(&cachep->nodelists[node]->list_lock); |
1041 | cachep->nodelists[node]->free_limit = | |
a737b3e2 AM |
1042 | (1 + nr_cpus_node(node)) * |
1043 | cachep->batchcount + cachep->num; | |
e498be7d CL |
1044 | spin_unlock_irq(&cachep->nodelists[node]->list_lock); |
1045 | } | |
1046 | ||
a737b3e2 AM |
1047 | /* |
1048 | * Now we can go ahead with allocating the shared arrays and | |
1049 | * array caches | |
1050 | */ | |
e498be7d | 1051 | list_for_each_entry(cachep, &cache_chain, next) { |
cd105df4 | 1052 | struct array_cache *nc; |
4484ebf1 RT |
1053 | struct array_cache *shared; |
1054 | struct array_cache **alien; | |
cd105df4 | 1055 | |
e498be7d | 1056 | nc = alloc_arraycache(node, cachep->limit, |
4484ebf1 | 1057 | cachep->batchcount); |
1da177e4 LT |
1058 | if (!nc) |
1059 | goto bad; | |
4484ebf1 RT |
1060 | shared = alloc_arraycache(node, |
1061 | cachep->shared * cachep->batchcount, | |
1062 | 0xbaadf00d); | |
1063 | if (!shared) | |
1064 | goto bad; | |
7a21ef6f | 1065 | |
4484ebf1 RT |
1066 | alien = alloc_alien_cache(node, cachep->limit); |
1067 | if (!alien) | |
1068 | goto bad; | |
1da177e4 | 1069 | cachep->array[cpu] = nc; |
e498be7d CL |
1070 | l3 = cachep->nodelists[node]; |
1071 | BUG_ON(!l3); | |
e498be7d | 1072 | |
4484ebf1 RT |
1073 | spin_lock_irq(&l3->list_lock); |
1074 | if (!l3->shared) { | |
1075 | /* | |
1076 | * We are serialised from CPU_DEAD or | |
1077 | * CPU_UP_CANCELLED by the cpucontrol lock | |
1078 | */ | |
1079 | l3->shared = shared; | |
1080 | shared = NULL; | |
e498be7d | 1081 | } |
4484ebf1 RT |
1082 | #ifdef CONFIG_NUMA |
1083 | if (!l3->alien) { | |
1084 | l3->alien = alien; | |
1085 | alien = NULL; | |
1086 | } | |
1087 | #endif | |
1088 | spin_unlock_irq(&l3->list_lock); | |
4484ebf1 RT |
1089 | kfree(shared); |
1090 | free_alien_cache(alien); | |
1da177e4 | 1091 | } |
fc0abb14 | 1092 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1093 | break; |
1094 | case CPU_ONLINE: | |
1095 | start_cpu_timer(cpu); | |
1096 | break; | |
1097 | #ifdef CONFIG_HOTPLUG_CPU | |
1098 | case CPU_DEAD: | |
4484ebf1 RT |
1099 | /* |
1100 | * Even if all the cpus of a node are down, we don't free the | |
1101 | * kmem_list3 of any cache. This to avoid a race between | |
1102 | * cpu_down, and a kmalloc allocation from another cpu for | |
1103 | * memory from the node of the cpu going down. The list3 | |
1104 | * structure is usually allocated from kmem_cache_create() and | |
1105 | * gets destroyed at kmem_cache_destroy(). | |
1106 | */ | |
1da177e4 LT |
1107 | /* fall thru */ |
1108 | case CPU_UP_CANCELED: | |
fc0abb14 | 1109 | mutex_lock(&cache_chain_mutex); |
1da177e4 LT |
1110 | list_for_each_entry(cachep, &cache_chain, next) { |
1111 | struct array_cache *nc; | |
4484ebf1 RT |
1112 | struct array_cache *shared; |
1113 | struct array_cache **alien; | |
e498be7d | 1114 | cpumask_t mask; |
1da177e4 | 1115 | |
e498be7d | 1116 | mask = node_to_cpumask(node); |
1da177e4 LT |
1117 | /* cpu is dead; no one can alloc from it. */ |
1118 | nc = cachep->array[cpu]; | |
1119 | cachep->array[cpu] = NULL; | |
e498be7d CL |
1120 | l3 = cachep->nodelists[node]; |
1121 | ||
1122 | if (!l3) | |
4484ebf1 | 1123 | goto free_array_cache; |
e498be7d | 1124 | |
ca3b9b91 | 1125 | spin_lock_irq(&l3->list_lock); |
e498be7d CL |
1126 | |
1127 | /* Free limit for this kmem_list3 */ | |
1128 | l3->free_limit -= cachep->batchcount; | |
1129 | if (nc) | |
ff69416e | 1130 | free_block(cachep, nc->entry, nc->avail, node); |
e498be7d CL |
1131 | |
1132 | if (!cpus_empty(mask)) { | |
ca3b9b91 | 1133 | spin_unlock_irq(&l3->list_lock); |
4484ebf1 | 1134 | goto free_array_cache; |
b28a02de | 1135 | } |
e498be7d | 1136 | |
4484ebf1 RT |
1137 | shared = l3->shared; |
1138 | if (shared) { | |
e498be7d | 1139 | free_block(cachep, l3->shared->entry, |
b28a02de | 1140 | l3->shared->avail, node); |
e498be7d CL |
1141 | l3->shared = NULL; |
1142 | } | |
e498be7d | 1143 | |
4484ebf1 RT |
1144 | alien = l3->alien; |
1145 | l3->alien = NULL; | |
1146 | ||
1147 | spin_unlock_irq(&l3->list_lock); | |
1148 | ||
1149 | kfree(shared); | |
1150 | if (alien) { | |
1151 | drain_alien_cache(cachep, alien); | |
1152 | free_alien_cache(alien); | |
e498be7d | 1153 | } |
4484ebf1 | 1154 | free_array_cache: |
1da177e4 LT |
1155 | kfree(nc); |
1156 | } | |
4484ebf1 RT |
1157 | /* |
1158 | * In the previous loop, all the objects were freed to | |
1159 | * the respective cache's slabs, now we can go ahead and | |
1160 | * shrink each nodelist to its limit. | |
1161 | */ | |
1162 | list_for_each_entry(cachep, &cache_chain, next) { | |
1163 | l3 = cachep->nodelists[node]; | |
1164 | if (!l3) | |
1165 | continue; | |
1166 | spin_lock_irq(&l3->list_lock); | |
1167 | /* free slabs belonging to this node */ | |
1168 | __node_shrink(cachep, node); | |
1169 | spin_unlock_irq(&l3->list_lock); | |
1170 | } | |
fc0abb14 | 1171 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1172 | break; |
1173 | #endif | |
1174 | } | |
1175 | return NOTIFY_OK; | |
a737b3e2 | 1176 | bad: |
fc0abb14 | 1177 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1178 | return NOTIFY_BAD; |
1179 | } | |
1180 | ||
1181 | static struct notifier_block cpucache_notifier = { &cpuup_callback, NULL, 0 }; | |
1182 | ||
e498be7d CL |
1183 | /* |
1184 | * swap the static kmem_list3 with kmalloced memory | |
1185 | */ | |
a737b3e2 AM |
1186 | static void init_list(struct kmem_cache *cachep, struct kmem_list3 *list, |
1187 | int nodeid) | |
e498be7d CL |
1188 | { |
1189 | struct kmem_list3 *ptr; | |
1190 | ||
1191 | BUG_ON(cachep->nodelists[nodeid] != list); | |
1192 | ptr = kmalloc_node(sizeof(struct kmem_list3), GFP_KERNEL, nodeid); | |
1193 | BUG_ON(!ptr); | |
1194 | ||
1195 | local_irq_disable(); | |
1196 | memcpy(ptr, list, sizeof(struct kmem_list3)); | |
1197 | MAKE_ALL_LISTS(cachep, ptr, nodeid); | |
1198 | cachep->nodelists[nodeid] = ptr; | |
1199 | local_irq_enable(); | |
1200 | } | |
1201 | ||
a737b3e2 AM |
1202 | /* |
1203 | * Initialisation. Called after the page allocator have been initialised and | |
1204 | * before smp_init(). | |
1da177e4 LT |
1205 | */ |
1206 | void __init kmem_cache_init(void) | |
1207 | { | |
1208 | size_t left_over; | |
1209 | struct cache_sizes *sizes; | |
1210 | struct cache_names *names; | |
e498be7d | 1211 | int i; |
07ed76b2 | 1212 | int order; |
e498be7d CL |
1213 | |
1214 | for (i = 0; i < NUM_INIT_LISTS; i++) { | |
1215 | kmem_list3_init(&initkmem_list3[i]); | |
1216 | if (i < MAX_NUMNODES) | |
1217 | cache_cache.nodelists[i] = NULL; | |
1218 | } | |
1da177e4 LT |
1219 | |
1220 | /* | |
1221 | * Fragmentation resistance on low memory - only use bigger | |
1222 | * page orders on machines with more than 32MB of memory. | |
1223 | */ | |
1224 | if (num_physpages > (32 << 20) >> PAGE_SHIFT) | |
1225 | slab_break_gfp_order = BREAK_GFP_ORDER_HI; | |
1226 | ||
1da177e4 LT |
1227 | /* Bootstrap is tricky, because several objects are allocated |
1228 | * from caches that do not exist yet: | |
a737b3e2 AM |
1229 | * 1) initialize the cache_cache cache: it contains the struct |
1230 | * kmem_cache structures of all caches, except cache_cache itself: | |
1231 | * cache_cache is statically allocated. | |
e498be7d CL |
1232 | * Initially an __init data area is used for the head array and the |
1233 | * kmem_list3 structures, it's replaced with a kmalloc allocated | |
1234 | * array at the end of the bootstrap. | |
1da177e4 | 1235 | * 2) Create the first kmalloc cache. |
343e0d7a | 1236 | * The struct kmem_cache for the new cache is allocated normally. |
e498be7d CL |
1237 | * An __init data area is used for the head array. |
1238 | * 3) Create the remaining kmalloc caches, with minimally sized | |
1239 | * head arrays. | |
1da177e4 LT |
1240 | * 4) Replace the __init data head arrays for cache_cache and the first |
1241 | * kmalloc cache with kmalloc allocated arrays. | |
e498be7d CL |
1242 | * 5) Replace the __init data for kmem_list3 for cache_cache and |
1243 | * the other cache's with kmalloc allocated memory. | |
1244 | * 6) Resize the head arrays of the kmalloc caches to their final sizes. | |
1da177e4 LT |
1245 | */ |
1246 | ||
1247 | /* 1) create the cache_cache */ | |
1da177e4 LT |
1248 | INIT_LIST_HEAD(&cache_chain); |
1249 | list_add(&cache_cache.next, &cache_chain); | |
1250 | cache_cache.colour_off = cache_line_size(); | |
1251 | cache_cache.array[smp_processor_id()] = &initarray_cache.cache; | |
e498be7d | 1252 | cache_cache.nodelists[numa_node_id()] = &initkmem_list3[CACHE_CACHE]; |
1da177e4 | 1253 | |
a737b3e2 AM |
1254 | cache_cache.buffer_size = ALIGN(cache_cache.buffer_size, |
1255 | cache_line_size()); | |
1da177e4 | 1256 | |
07ed76b2 JS |
1257 | for (order = 0; order < MAX_ORDER; order++) { |
1258 | cache_estimate(order, cache_cache.buffer_size, | |
1259 | cache_line_size(), 0, &left_over, &cache_cache.num); | |
1260 | if (cache_cache.num) | |
1261 | break; | |
1262 | } | |
1da177e4 LT |
1263 | if (!cache_cache.num) |
1264 | BUG(); | |
07ed76b2 | 1265 | cache_cache.gfporder = order; |
b28a02de | 1266 | cache_cache.colour = left_over / cache_cache.colour_off; |
b28a02de PE |
1267 | cache_cache.slab_size = ALIGN(cache_cache.num * sizeof(kmem_bufctl_t) + |
1268 | sizeof(struct slab), cache_line_size()); | |
1da177e4 LT |
1269 | |
1270 | /* 2+3) create the kmalloc caches */ | |
1271 | sizes = malloc_sizes; | |
1272 | names = cache_names; | |
1273 | ||
a737b3e2 AM |
1274 | /* |
1275 | * Initialize the caches that provide memory for the array cache and the | |
1276 | * kmem_list3 structures first. Without this, further allocations will | |
1277 | * bug. | |
e498be7d CL |
1278 | */ |
1279 | ||
1280 | sizes[INDEX_AC].cs_cachep = kmem_cache_create(names[INDEX_AC].name, | |
a737b3e2 AM |
1281 | sizes[INDEX_AC].cs_size, |
1282 | ARCH_KMALLOC_MINALIGN, | |
1283 | ARCH_KMALLOC_FLAGS|SLAB_PANIC, | |
1284 | NULL, NULL); | |
e498be7d | 1285 | |
a737b3e2 | 1286 | if (INDEX_AC != INDEX_L3) { |
e498be7d | 1287 | sizes[INDEX_L3].cs_cachep = |
a737b3e2 AM |
1288 | kmem_cache_create(names[INDEX_L3].name, |
1289 | sizes[INDEX_L3].cs_size, | |
1290 | ARCH_KMALLOC_MINALIGN, | |
1291 | ARCH_KMALLOC_FLAGS|SLAB_PANIC, | |
1292 | NULL, NULL); | |
1293 | } | |
e498be7d | 1294 | |
1da177e4 | 1295 | while (sizes->cs_size != ULONG_MAX) { |
e498be7d CL |
1296 | /* |
1297 | * For performance, all the general caches are L1 aligned. | |
1da177e4 LT |
1298 | * This should be particularly beneficial on SMP boxes, as it |
1299 | * eliminates "false sharing". | |
1300 | * Note for systems short on memory removing the alignment will | |
e498be7d CL |
1301 | * allow tighter packing of the smaller caches. |
1302 | */ | |
a737b3e2 | 1303 | if (!sizes->cs_cachep) { |
e498be7d | 1304 | sizes->cs_cachep = kmem_cache_create(names->name, |
a737b3e2 AM |
1305 | sizes->cs_size, |
1306 | ARCH_KMALLOC_MINALIGN, | |
1307 | ARCH_KMALLOC_FLAGS|SLAB_PANIC, | |
1308 | NULL, NULL); | |
1309 | } | |
1da177e4 LT |
1310 | |
1311 | /* Inc off-slab bufctl limit until the ceiling is hit. */ | |
1312 | if (!(OFF_SLAB(sizes->cs_cachep))) { | |
b28a02de | 1313 | offslab_limit = sizes->cs_size - sizeof(struct slab); |
1da177e4 LT |
1314 | offslab_limit /= sizeof(kmem_bufctl_t); |
1315 | } | |
1316 | ||
1317 | sizes->cs_dmacachep = kmem_cache_create(names->name_dma, | |
a737b3e2 AM |
1318 | sizes->cs_size, |
1319 | ARCH_KMALLOC_MINALIGN, | |
1320 | ARCH_KMALLOC_FLAGS|SLAB_CACHE_DMA| | |
1321 | SLAB_PANIC, | |
1322 | NULL, NULL); | |
1da177e4 LT |
1323 | sizes++; |
1324 | names++; | |
1325 | } | |
1326 | /* 4) Replace the bootstrap head arrays */ | |
1327 | { | |
b28a02de | 1328 | void *ptr; |
e498be7d | 1329 | |
1da177e4 | 1330 | ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d | 1331 | |
1da177e4 | 1332 | local_irq_disable(); |
9a2dba4b PE |
1333 | BUG_ON(cpu_cache_get(&cache_cache) != &initarray_cache.cache); |
1334 | memcpy(ptr, cpu_cache_get(&cache_cache), | |
b28a02de | 1335 | sizeof(struct arraycache_init)); |
1da177e4 LT |
1336 | cache_cache.array[smp_processor_id()] = ptr; |
1337 | local_irq_enable(); | |
e498be7d | 1338 | |
1da177e4 | 1339 | ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d | 1340 | |
1da177e4 | 1341 | local_irq_disable(); |
9a2dba4b | 1342 | BUG_ON(cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep) |
b28a02de | 1343 | != &initarray_generic.cache); |
9a2dba4b | 1344 | memcpy(ptr, cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep), |
b28a02de | 1345 | sizeof(struct arraycache_init)); |
e498be7d | 1346 | malloc_sizes[INDEX_AC].cs_cachep->array[smp_processor_id()] = |
b28a02de | 1347 | ptr; |
1da177e4 LT |
1348 | local_irq_enable(); |
1349 | } | |
e498be7d CL |
1350 | /* 5) Replace the bootstrap kmem_list3's */ |
1351 | { | |
1352 | int node; | |
1353 | /* Replace the static kmem_list3 structures for the boot cpu */ | |
1354 | init_list(&cache_cache, &initkmem_list3[CACHE_CACHE], | |
b28a02de | 1355 | numa_node_id()); |
e498be7d CL |
1356 | |
1357 | for_each_online_node(node) { | |
1358 | init_list(malloc_sizes[INDEX_AC].cs_cachep, | |
b28a02de | 1359 | &initkmem_list3[SIZE_AC + node], node); |
e498be7d CL |
1360 | |
1361 | if (INDEX_AC != INDEX_L3) { | |
1362 | init_list(malloc_sizes[INDEX_L3].cs_cachep, | |
b28a02de PE |
1363 | &initkmem_list3[SIZE_L3 + node], |
1364 | node); | |
e498be7d CL |
1365 | } |
1366 | } | |
1367 | } | |
1da177e4 | 1368 | |
e498be7d | 1369 | /* 6) resize the head arrays to their final sizes */ |
1da177e4 | 1370 | { |
343e0d7a | 1371 | struct kmem_cache *cachep; |
fc0abb14 | 1372 | mutex_lock(&cache_chain_mutex); |
1da177e4 | 1373 | list_for_each_entry(cachep, &cache_chain, next) |
a737b3e2 | 1374 | enable_cpucache(cachep); |
fc0abb14 | 1375 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1376 | } |
1377 | ||
1378 | /* Done! */ | |
1379 | g_cpucache_up = FULL; | |
1380 | ||
a737b3e2 AM |
1381 | /* |
1382 | * Register a cpu startup notifier callback that initializes | |
1383 | * cpu_cache_get for all new cpus | |
1da177e4 LT |
1384 | */ |
1385 | register_cpu_notifier(&cpucache_notifier); | |
1da177e4 | 1386 | |
a737b3e2 AM |
1387 | /* |
1388 | * The reap timers are started later, with a module init call: That part | |
1389 | * of the kernel is not yet operational. | |
1da177e4 LT |
1390 | */ |
1391 | } | |
1392 | ||
1393 | static int __init cpucache_init(void) | |
1394 | { | |
1395 | int cpu; | |
1396 | ||
a737b3e2 AM |
1397 | /* |
1398 | * Register the timers that return unneeded pages to the page allocator | |
1da177e4 | 1399 | */ |
e498be7d | 1400 | for_each_online_cpu(cpu) |
a737b3e2 | 1401 | start_cpu_timer(cpu); |
1da177e4 LT |
1402 | return 0; |
1403 | } | |
1da177e4 LT |
1404 | __initcall(cpucache_init); |
1405 | ||
1406 | /* | |
1407 | * Interface to system's page allocator. No need to hold the cache-lock. | |
1408 | * | |
1409 | * If we requested dmaable memory, we will get it. Even if we | |
1410 | * did not request dmaable memory, we might get it, but that | |
1411 | * would be relatively rare and ignorable. | |
1412 | */ | |
343e0d7a | 1413 | static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 LT |
1414 | { |
1415 | struct page *page; | |
1416 | void *addr; | |
1417 | int i; | |
1418 | ||
1419 | flags |= cachep->gfpflags; | |
50c85a19 | 1420 | page = alloc_pages_node(nodeid, flags, cachep->gfporder); |
1da177e4 LT |
1421 | if (!page) |
1422 | return NULL; | |
1423 | addr = page_address(page); | |
1424 | ||
1425 | i = (1 << cachep->gfporder); | |
1426 | if (cachep->flags & SLAB_RECLAIM_ACCOUNT) | |
1427 | atomic_add(i, &slab_reclaim_pages); | |
1428 | add_page_state(nr_slab, i); | |
1429 | while (i--) { | |
f205b2fe | 1430 | __SetPageSlab(page); |
1da177e4 LT |
1431 | page++; |
1432 | } | |
1433 | return addr; | |
1434 | } | |
1435 | ||
1436 | /* | |
1437 | * Interface to system's page release. | |
1438 | */ | |
343e0d7a | 1439 | static void kmem_freepages(struct kmem_cache *cachep, void *addr) |
1da177e4 | 1440 | { |
b28a02de | 1441 | unsigned long i = (1 << cachep->gfporder); |
1da177e4 LT |
1442 | struct page *page = virt_to_page(addr); |
1443 | const unsigned long nr_freed = i; | |
1444 | ||
1445 | while (i--) { | |
f205b2fe NP |
1446 | BUG_ON(!PageSlab(page)); |
1447 | __ClearPageSlab(page); | |
1da177e4 LT |
1448 | page++; |
1449 | } | |
1450 | sub_page_state(nr_slab, nr_freed); | |
1451 | if (current->reclaim_state) | |
1452 | current->reclaim_state->reclaimed_slab += nr_freed; | |
1453 | free_pages((unsigned long)addr, cachep->gfporder); | |
b28a02de PE |
1454 | if (cachep->flags & SLAB_RECLAIM_ACCOUNT) |
1455 | atomic_sub(1 << cachep->gfporder, &slab_reclaim_pages); | |
1da177e4 LT |
1456 | } |
1457 | ||
1458 | static void kmem_rcu_free(struct rcu_head *head) | |
1459 | { | |
b28a02de | 1460 | struct slab_rcu *slab_rcu = (struct slab_rcu *)head; |
343e0d7a | 1461 | struct kmem_cache *cachep = slab_rcu->cachep; |
1da177e4 LT |
1462 | |
1463 | kmem_freepages(cachep, slab_rcu->addr); | |
1464 | if (OFF_SLAB(cachep)) | |
1465 | kmem_cache_free(cachep->slabp_cache, slab_rcu); | |
1466 | } | |
1467 | ||
1468 | #if DEBUG | |
1469 | ||
1470 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
343e0d7a | 1471 | static void store_stackinfo(struct kmem_cache *cachep, unsigned long *addr, |
b28a02de | 1472 | unsigned long caller) |
1da177e4 | 1473 | { |
3dafccf2 | 1474 | int size = obj_size(cachep); |
1da177e4 | 1475 | |
3dafccf2 | 1476 | addr = (unsigned long *)&((char *)addr)[obj_offset(cachep)]; |
1da177e4 | 1477 | |
b28a02de | 1478 | if (size < 5 * sizeof(unsigned long)) |
1da177e4 LT |
1479 | return; |
1480 | ||
b28a02de PE |
1481 | *addr++ = 0x12345678; |
1482 | *addr++ = caller; | |
1483 | *addr++ = smp_processor_id(); | |
1484 | size -= 3 * sizeof(unsigned long); | |
1da177e4 LT |
1485 | { |
1486 | unsigned long *sptr = &caller; | |
1487 | unsigned long svalue; | |
1488 | ||
1489 | while (!kstack_end(sptr)) { | |
1490 | svalue = *sptr++; | |
1491 | if (kernel_text_address(svalue)) { | |
b28a02de | 1492 | *addr++ = svalue; |
1da177e4 LT |
1493 | size -= sizeof(unsigned long); |
1494 | if (size <= sizeof(unsigned long)) | |
1495 | break; | |
1496 | } | |
1497 | } | |
1498 | ||
1499 | } | |
b28a02de | 1500 | *addr++ = 0x87654321; |
1da177e4 LT |
1501 | } |
1502 | #endif | |
1503 | ||
343e0d7a | 1504 | static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) |
1da177e4 | 1505 | { |
3dafccf2 MS |
1506 | int size = obj_size(cachep); |
1507 | addr = &((char *)addr)[obj_offset(cachep)]; | |
1da177e4 LT |
1508 | |
1509 | memset(addr, val, size); | |
b28a02de | 1510 | *(unsigned char *)(addr + size - 1) = POISON_END; |
1da177e4 LT |
1511 | } |
1512 | ||
1513 | static void dump_line(char *data, int offset, int limit) | |
1514 | { | |
1515 | int i; | |
1516 | printk(KERN_ERR "%03x:", offset); | |
a737b3e2 | 1517 | for (i = 0; i < limit; i++) |
b28a02de | 1518 | printk(" %02x", (unsigned char)data[offset + i]); |
1da177e4 LT |
1519 | printk("\n"); |
1520 | } | |
1521 | #endif | |
1522 | ||
1523 | #if DEBUG | |
1524 | ||
343e0d7a | 1525 | static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines) |
1da177e4 LT |
1526 | { |
1527 | int i, size; | |
1528 | char *realobj; | |
1529 | ||
1530 | if (cachep->flags & SLAB_RED_ZONE) { | |
1531 | printk(KERN_ERR "Redzone: 0x%lx/0x%lx.\n", | |
a737b3e2 AM |
1532 | *dbg_redzone1(cachep, objp), |
1533 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
1534 | } |
1535 | ||
1536 | if (cachep->flags & SLAB_STORE_USER) { | |
1537 | printk(KERN_ERR "Last user: [<%p>]", | |
a737b3e2 | 1538 | *dbg_userword(cachep, objp)); |
1da177e4 | 1539 | print_symbol("(%s)", |
a737b3e2 | 1540 | (unsigned long)*dbg_userword(cachep, objp)); |
1da177e4 LT |
1541 | printk("\n"); |
1542 | } | |
3dafccf2 MS |
1543 | realobj = (char *)objp + obj_offset(cachep); |
1544 | size = obj_size(cachep); | |
b28a02de | 1545 | for (i = 0; i < size && lines; i += 16, lines--) { |
1da177e4 LT |
1546 | int limit; |
1547 | limit = 16; | |
b28a02de PE |
1548 | if (i + limit > size) |
1549 | limit = size - i; | |
1da177e4 LT |
1550 | dump_line(realobj, i, limit); |
1551 | } | |
1552 | } | |
1553 | ||
343e0d7a | 1554 | static void check_poison_obj(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
1555 | { |
1556 | char *realobj; | |
1557 | int size, i; | |
1558 | int lines = 0; | |
1559 | ||
3dafccf2 MS |
1560 | realobj = (char *)objp + obj_offset(cachep); |
1561 | size = obj_size(cachep); | |
1da177e4 | 1562 | |
b28a02de | 1563 | for (i = 0; i < size; i++) { |
1da177e4 | 1564 | char exp = POISON_FREE; |
b28a02de | 1565 | if (i == size - 1) |
1da177e4 LT |
1566 | exp = POISON_END; |
1567 | if (realobj[i] != exp) { | |
1568 | int limit; | |
1569 | /* Mismatch ! */ | |
1570 | /* Print header */ | |
1571 | if (lines == 0) { | |
b28a02de | 1572 | printk(KERN_ERR |
a737b3e2 AM |
1573 | "Slab corruption: start=%p, len=%d\n", |
1574 | realobj, size); | |
1da177e4 LT |
1575 | print_objinfo(cachep, objp, 0); |
1576 | } | |
1577 | /* Hexdump the affected line */ | |
b28a02de | 1578 | i = (i / 16) * 16; |
1da177e4 | 1579 | limit = 16; |
b28a02de PE |
1580 | if (i + limit > size) |
1581 | limit = size - i; | |
1da177e4 LT |
1582 | dump_line(realobj, i, limit); |
1583 | i += 16; | |
1584 | lines++; | |
1585 | /* Limit to 5 lines */ | |
1586 | if (lines > 5) | |
1587 | break; | |
1588 | } | |
1589 | } | |
1590 | if (lines != 0) { | |
1591 | /* Print some data about the neighboring objects, if they | |
1592 | * exist: | |
1593 | */ | |
6ed5eb22 | 1594 | struct slab *slabp = virt_to_slab(objp); |
8fea4e96 | 1595 | unsigned int objnr; |
1da177e4 | 1596 | |
8fea4e96 | 1597 | objnr = obj_to_index(cachep, slabp, objp); |
1da177e4 | 1598 | if (objnr) { |
8fea4e96 | 1599 | objp = index_to_obj(cachep, slabp, objnr - 1); |
3dafccf2 | 1600 | realobj = (char *)objp + obj_offset(cachep); |
1da177e4 | 1601 | printk(KERN_ERR "Prev obj: start=%p, len=%d\n", |
b28a02de | 1602 | realobj, size); |
1da177e4 LT |
1603 | print_objinfo(cachep, objp, 2); |
1604 | } | |
b28a02de | 1605 | if (objnr + 1 < cachep->num) { |
8fea4e96 | 1606 | objp = index_to_obj(cachep, slabp, objnr + 1); |
3dafccf2 | 1607 | realobj = (char *)objp + obj_offset(cachep); |
1da177e4 | 1608 | printk(KERN_ERR "Next obj: start=%p, len=%d\n", |
b28a02de | 1609 | realobj, size); |
1da177e4 LT |
1610 | print_objinfo(cachep, objp, 2); |
1611 | } | |
1612 | } | |
1613 | } | |
1614 | #endif | |
1615 | ||
12dd36fa MD |
1616 | #if DEBUG |
1617 | /** | |
1618 | * slab_destroy_objs - call the registered destructor for each object in | |
1619 | * a slab that is to be destroyed. | |
1da177e4 | 1620 | */ |
343e0d7a | 1621 | static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp) |
1da177e4 | 1622 | { |
1da177e4 LT |
1623 | int i; |
1624 | for (i = 0; i < cachep->num; i++) { | |
8fea4e96 | 1625 | void *objp = index_to_obj(cachep, slabp, i); |
1da177e4 LT |
1626 | |
1627 | if (cachep->flags & SLAB_POISON) { | |
1628 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
a737b3e2 AM |
1629 | if (cachep->buffer_size % PAGE_SIZE == 0 && |
1630 | OFF_SLAB(cachep)) | |
b28a02de | 1631 | kernel_map_pages(virt_to_page(objp), |
a737b3e2 | 1632 | cachep->buffer_size / PAGE_SIZE, 1); |
1da177e4 LT |
1633 | else |
1634 | check_poison_obj(cachep, objp); | |
1635 | #else | |
1636 | check_poison_obj(cachep, objp); | |
1637 | #endif | |
1638 | } | |
1639 | if (cachep->flags & SLAB_RED_ZONE) { | |
1640 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) | |
1641 | slab_error(cachep, "start of a freed object " | |
b28a02de | 1642 | "was overwritten"); |
1da177e4 LT |
1643 | if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) |
1644 | slab_error(cachep, "end of a freed object " | |
b28a02de | 1645 | "was overwritten"); |
1da177e4 LT |
1646 | } |
1647 | if (cachep->dtor && !(cachep->flags & SLAB_POISON)) | |
3dafccf2 | 1648 | (cachep->dtor) (objp + obj_offset(cachep), cachep, 0); |
1da177e4 | 1649 | } |
12dd36fa | 1650 | } |
1da177e4 | 1651 | #else |
343e0d7a | 1652 | static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp) |
12dd36fa | 1653 | { |
1da177e4 LT |
1654 | if (cachep->dtor) { |
1655 | int i; | |
1656 | for (i = 0; i < cachep->num; i++) { | |
8fea4e96 | 1657 | void *objp = index_to_obj(cachep, slabp, i); |
b28a02de | 1658 | (cachep->dtor) (objp, cachep, 0); |
1da177e4 LT |
1659 | } |
1660 | } | |
12dd36fa | 1661 | } |
1da177e4 LT |
1662 | #endif |
1663 | ||
a737b3e2 | 1664 | /* |
12dd36fa | 1665 | * Destroy all the objs in a slab, and release the mem back to the system. |
a737b3e2 AM |
1666 | * Before calling the slab must have been unlinked from the cache. The |
1667 | * cache-lock is not held/needed. | |
12dd36fa | 1668 | */ |
343e0d7a | 1669 | static void slab_destroy(struct kmem_cache *cachep, struct slab *slabp) |
12dd36fa MD |
1670 | { |
1671 | void *addr = slabp->s_mem - slabp->colouroff; | |
1672 | ||
1673 | slab_destroy_objs(cachep, slabp); | |
1da177e4 LT |
1674 | if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) { |
1675 | struct slab_rcu *slab_rcu; | |
1676 | ||
b28a02de | 1677 | slab_rcu = (struct slab_rcu *)slabp; |
1da177e4 LT |
1678 | slab_rcu->cachep = cachep; |
1679 | slab_rcu->addr = addr; | |
1680 | call_rcu(&slab_rcu->head, kmem_rcu_free); | |
1681 | } else { | |
1682 | kmem_freepages(cachep, addr); | |
1683 | if (OFF_SLAB(cachep)) | |
1684 | kmem_cache_free(cachep->slabp_cache, slabp); | |
1685 | } | |
1686 | } | |
1687 | ||
a737b3e2 AM |
1688 | /* |
1689 | * For setting up all the kmem_list3s for cache whose buffer_size is same as | |
1690 | * size of kmem_list3. | |
1691 | */ | |
343e0d7a | 1692 | static void set_up_list3s(struct kmem_cache *cachep, int index) |
e498be7d CL |
1693 | { |
1694 | int node; | |
1695 | ||
1696 | for_each_online_node(node) { | |
b28a02de | 1697 | cachep->nodelists[node] = &initkmem_list3[index + node]; |
e498be7d | 1698 | cachep->nodelists[node]->next_reap = jiffies + |
b28a02de PE |
1699 | REAPTIMEOUT_LIST3 + |
1700 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; | |
e498be7d CL |
1701 | } |
1702 | } | |
1703 | ||
4d268eba | 1704 | /** |
a70773dd RD |
1705 | * calculate_slab_order - calculate size (page order) of slabs |
1706 | * @cachep: pointer to the cache that is being created | |
1707 | * @size: size of objects to be created in this cache. | |
1708 | * @align: required alignment for the objects. | |
1709 | * @flags: slab allocation flags | |
1710 | * | |
1711 | * Also calculates the number of objects per slab. | |
4d268eba PE |
1712 | * |
1713 | * This could be made much more intelligent. For now, try to avoid using | |
1714 | * high order pages for slabs. When the gfp() functions are more friendly | |
1715 | * towards high-order requests, this should be changed. | |
1716 | */ | |
a737b3e2 | 1717 | static size_t calculate_slab_order(struct kmem_cache *cachep, |
ee13d785 | 1718 | size_t size, size_t align, unsigned long flags) |
4d268eba PE |
1719 | { |
1720 | size_t left_over = 0; | |
9888e6fa | 1721 | int gfporder; |
4d268eba | 1722 | |
a737b3e2 | 1723 | for (gfporder = 0; gfporder <= MAX_GFP_ORDER; gfporder++) { |
4d268eba PE |
1724 | unsigned int num; |
1725 | size_t remainder; | |
1726 | ||
9888e6fa | 1727 | cache_estimate(gfporder, size, align, flags, &remainder, &num); |
4d268eba PE |
1728 | if (!num) |
1729 | continue; | |
9888e6fa | 1730 | |
4d268eba | 1731 | /* More than offslab_limit objects will cause problems */ |
9888e6fa | 1732 | if ((flags & CFLGS_OFF_SLAB) && num > offslab_limit) |
4d268eba PE |
1733 | break; |
1734 | ||
9888e6fa | 1735 | /* Found something acceptable - save it away */ |
4d268eba | 1736 | cachep->num = num; |
9888e6fa | 1737 | cachep->gfporder = gfporder; |
4d268eba PE |
1738 | left_over = remainder; |
1739 | ||
f78bb8ad LT |
1740 | /* |
1741 | * A VFS-reclaimable slab tends to have most allocations | |
1742 | * as GFP_NOFS and we really don't want to have to be allocating | |
1743 | * higher-order pages when we are unable to shrink dcache. | |
1744 | */ | |
1745 | if (flags & SLAB_RECLAIM_ACCOUNT) | |
1746 | break; | |
1747 | ||
4d268eba PE |
1748 | /* |
1749 | * Large number of objects is good, but very large slabs are | |
1750 | * currently bad for the gfp()s. | |
1751 | */ | |
9888e6fa | 1752 | if (gfporder >= slab_break_gfp_order) |
4d268eba PE |
1753 | break; |
1754 | ||
9888e6fa LT |
1755 | /* |
1756 | * Acceptable internal fragmentation? | |
1757 | */ | |
a737b3e2 | 1758 | if (left_over * 8 <= (PAGE_SIZE << gfporder)) |
4d268eba PE |
1759 | break; |
1760 | } | |
1761 | return left_over; | |
1762 | } | |
1763 | ||
f30cf7d1 PE |
1764 | static void setup_cpu_cache(struct kmem_cache *cachep) |
1765 | { | |
1766 | if (g_cpucache_up == FULL) { | |
1767 | enable_cpucache(cachep); | |
1768 | return; | |
1769 | } | |
1770 | if (g_cpucache_up == NONE) { | |
1771 | /* | |
1772 | * Note: the first kmem_cache_create must create the cache | |
1773 | * that's used by kmalloc(24), otherwise the creation of | |
1774 | * further caches will BUG(). | |
1775 | */ | |
1776 | cachep->array[smp_processor_id()] = &initarray_generic.cache; | |
1777 | ||
1778 | /* | |
1779 | * If the cache that's used by kmalloc(sizeof(kmem_list3)) is | |
1780 | * the first cache, then we need to set up all its list3s, | |
1781 | * otherwise the creation of further caches will BUG(). | |
1782 | */ | |
1783 | set_up_list3s(cachep, SIZE_AC); | |
1784 | if (INDEX_AC == INDEX_L3) | |
1785 | g_cpucache_up = PARTIAL_L3; | |
1786 | else | |
1787 | g_cpucache_up = PARTIAL_AC; | |
1788 | } else { | |
1789 | cachep->array[smp_processor_id()] = | |
1790 | kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); | |
1791 | ||
1792 | if (g_cpucache_up == PARTIAL_AC) { | |
1793 | set_up_list3s(cachep, SIZE_L3); | |
1794 | g_cpucache_up = PARTIAL_L3; | |
1795 | } else { | |
1796 | int node; | |
1797 | for_each_online_node(node) { | |
1798 | cachep->nodelists[node] = | |
1799 | kmalloc_node(sizeof(struct kmem_list3), | |
1800 | GFP_KERNEL, node); | |
1801 | BUG_ON(!cachep->nodelists[node]); | |
1802 | kmem_list3_init(cachep->nodelists[node]); | |
1803 | } | |
1804 | } | |
1805 | } | |
1806 | cachep->nodelists[numa_node_id()]->next_reap = | |
1807 | jiffies + REAPTIMEOUT_LIST3 + | |
1808 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; | |
1809 | ||
1810 | cpu_cache_get(cachep)->avail = 0; | |
1811 | cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES; | |
1812 | cpu_cache_get(cachep)->batchcount = 1; | |
1813 | cpu_cache_get(cachep)->touched = 0; | |
1814 | cachep->batchcount = 1; | |
1815 | cachep->limit = BOOT_CPUCACHE_ENTRIES; | |
1816 | } | |
1817 | ||
1da177e4 LT |
1818 | /** |
1819 | * kmem_cache_create - Create a cache. | |
1820 | * @name: A string which is used in /proc/slabinfo to identify this cache. | |
1821 | * @size: The size of objects to be created in this cache. | |
1822 | * @align: The required alignment for the objects. | |
1823 | * @flags: SLAB flags | |
1824 | * @ctor: A constructor for the objects. | |
1825 | * @dtor: A destructor for the objects. | |
1826 | * | |
1827 | * Returns a ptr to the cache on success, NULL on failure. | |
1828 | * Cannot be called within a int, but can be interrupted. | |
1829 | * The @ctor is run when new pages are allocated by the cache | |
1830 | * and the @dtor is run before the pages are handed back. | |
1831 | * | |
1832 | * @name must be valid until the cache is destroyed. This implies that | |
a737b3e2 AM |
1833 | * the module calling this has to destroy the cache before getting unloaded. |
1834 | * | |
1da177e4 LT |
1835 | * The flags are |
1836 | * | |
1837 | * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5) | |
1838 | * to catch references to uninitialised memory. | |
1839 | * | |
1840 | * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check | |
1841 | * for buffer overruns. | |
1842 | * | |
1843 | * %SLAB_NO_REAP - Don't automatically reap this cache when we're under | |
1844 | * memory pressure. | |
1845 | * | |
1846 | * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware | |
1847 | * cacheline. This can be beneficial if you're counting cycles as closely | |
1848 | * as davem. | |
1849 | */ | |
343e0d7a | 1850 | struct kmem_cache * |
1da177e4 | 1851 | kmem_cache_create (const char *name, size_t size, size_t align, |
a737b3e2 AM |
1852 | unsigned long flags, |
1853 | void (*ctor)(void*, struct kmem_cache *, unsigned long), | |
343e0d7a | 1854 | void (*dtor)(void*, struct kmem_cache *, unsigned long)) |
1da177e4 LT |
1855 | { |
1856 | size_t left_over, slab_size, ralign; | |
343e0d7a | 1857 | struct kmem_cache *cachep = NULL; |
4f12bb4f | 1858 | struct list_head *p; |
1da177e4 LT |
1859 | |
1860 | /* | |
1861 | * Sanity checks... these are all serious usage bugs. | |
1862 | */ | |
a737b3e2 | 1863 | if (!name || in_interrupt() || (size < BYTES_PER_WORD) || |
b28a02de | 1864 | (size > (1 << MAX_OBJ_ORDER) * PAGE_SIZE) || (dtor && !ctor)) { |
a737b3e2 AM |
1865 | printk(KERN_ERR "%s: Early error in slab %s\n", __FUNCTION__, |
1866 | name); | |
b28a02de PE |
1867 | BUG(); |
1868 | } | |
1da177e4 | 1869 | |
f0188f47 RT |
1870 | /* |
1871 | * Prevent CPUs from coming and going. | |
1872 | * lock_cpu_hotplug() nests outside cache_chain_mutex | |
1873 | */ | |
1874 | lock_cpu_hotplug(); | |
1875 | ||
fc0abb14 | 1876 | mutex_lock(&cache_chain_mutex); |
4f12bb4f AM |
1877 | |
1878 | list_for_each(p, &cache_chain) { | |
343e0d7a | 1879 | struct kmem_cache *pc = list_entry(p, struct kmem_cache, next); |
4f12bb4f AM |
1880 | mm_segment_t old_fs = get_fs(); |
1881 | char tmp; | |
1882 | int res; | |
1883 | ||
1884 | /* | |
1885 | * This happens when the module gets unloaded and doesn't | |
1886 | * destroy its slab cache and no-one else reuses the vmalloc | |
1887 | * area of the module. Print a warning. | |
1888 | */ | |
1889 | set_fs(KERNEL_DS); | |
1890 | res = __get_user(tmp, pc->name); | |
1891 | set_fs(old_fs); | |
1892 | if (res) { | |
1893 | printk("SLAB: cache with size %d has lost its name\n", | |
3dafccf2 | 1894 | pc->buffer_size); |
4f12bb4f AM |
1895 | continue; |
1896 | } | |
1897 | ||
b28a02de | 1898 | if (!strcmp(pc->name, name)) { |
4f12bb4f AM |
1899 | printk("kmem_cache_create: duplicate cache %s\n", name); |
1900 | dump_stack(); | |
1901 | goto oops; | |
1902 | } | |
1903 | } | |
1904 | ||
1da177e4 LT |
1905 | #if DEBUG |
1906 | WARN_ON(strchr(name, ' ')); /* It confuses parsers */ | |
1907 | if ((flags & SLAB_DEBUG_INITIAL) && !ctor) { | |
1908 | /* No constructor, but inital state check requested */ | |
1909 | printk(KERN_ERR "%s: No con, but init state check " | |
b28a02de | 1910 | "requested - %s\n", __FUNCTION__, name); |
1da177e4 LT |
1911 | flags &= ~SLAB_DEBUG_INITIAL; |
1912 | } | |
1da177e4 LT |
1913 | #if FORCED_DEBUG |
1914 | /* | |
1915 | * Enable redzoning and last user accounting, except for caches with | |
1916 | * large objects, if the increased size would increase the object size | |
1917 | * above the next power of two: caches with object sizes just above a | |
1918 | * power of two have a significant amount of internal fragmentation. | |
1919 | */ | |
a737b3e2 | 1920 | if (size < 4096 || fls(size - 1) == fls(size-1 + 3 * BYTES_PER_WORD)) |
b28a02de | 1921 | flags |= SLAB_RED_ZONE | SLAB_STORE_USER; |
1da177e4 LT |
1922 | if (!(flags & SLAB_DESTROY_BY_RCU)) |
1923 | flags |= SLAB_POISON; | |
1924 | #endif | |
1925 | if (flags & SLAB_DESTROY_BY_RCU) | |
1926 | BUG_ON(flags & SLAB_POISON); | |
1927 | #endif | |
1928 | if (flags & SLAB_DESTROY_BY_RCU) | |
1929 | BUG_ON(dtor); | |
1930 | ||
1931 | /* | |
a737b3e2 AM |
1932 | * Always checks flags, a caller might be expecting debug support which |
1933 | * isn't available. | |
1da177e4 LT |
1934 | */ |
1935 | if (flags & ~CREATE_MASK) | |
1936 | BUG(); | |
1937 | ||
a737b3e2 AM |
1938 | /* |
1939 | * Check that size is in terms of words. This is needed to avoid | |
1da177e4 LT |
1940 | * unaligned accesses for some archs when redzoning is used, and makes |
1941 | * sure any on-slab bufctl's are also correctly aligned. | |
1942 | */ | |
b28a02de PE |
1943 | if (size & (BYTES_PER_WORD - 1)) { |
1944 | size += (BYTES_PER_WORD - 1); | |
1945 | size &= ~(BYTES_PER_WORD - 1); | |
1da177e4 LT |
1946 | } |
1947 | ||
a737b3e2 AM |
1948 | /* calculate the final buffer alignment: */ |
1949 | ||
1da177e4 LT |
1950 | /* 1) arch recommendation: can be overridden for debug */ |
1951 | if (flags & SLAB_HWCACHE_ALIGN) { | |
a737b3e2 AM |
1952 | /* |
1953 | * Default alignment: as specified by the arch code. Except if | |
1954 | * an object is really small, then squeeze multiple objects into | |
1955 | * one cacheline. | |
1da177e4 LT |
1956 | */ |
1957 | ralign = cache_line_size(); | |
b28a02de | 1958 | while (size <= ralign / 2) |
1da177e4 LT |
1959 | ralign /= 2; |
1960 | } else { | |
1961 | ralign = BYTES_PER_WORD; | |
1962 | } | |
1963 | /* 2) arch mandated alignment: disables debug if necessary */ | |
1964 | if (ralign < ARCH_SLAB_MINALIGN) { | |
1965 | ralign = ARCH_SLAB_MINALIGN; | |
1966 | if (ralign > BYTES_PER_WORD) | |
b28a02de | 1967 | flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
1da177e4 LT |
1968 | } |
1969 | /* 3) caller mandated alignment: disables debug if necessary */ | |
1970 | if (ralign < align) { | |
1971 | ralign = align; | |
1972 | if (ralign > BYTES_PER_WORD) | |
b28a02de | 1973 | flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
1da177e4 | 1974 | } |
a737b3e2 AM |
1975 | /* |
1976 | * 4) Store it. Note that the debug code below can reduce | |
1da177e4 LT |
1977 | * the alignment to BYTES_PER_WORD. |
1978 | */ | |
1979 | align = ralign; | |
1980 | ||
1981 | /* Get cache's description obj. */ | |
343e0d7a | 1982 | cachep = kmem_cache_alloc(&cache_cache, SLAB_KERNEL); |
1da177e4 | 1983 | if (!cachep) |
4f12bb4f | 1984 | goto oops; |
343e0d7a | 1985 | memset(cachep, 0, sizeof(struct kmem_cache)); |
1da177e4 LT |
1986 | |
1987 | #if DEBUG | |
3dafccf2 | 1988 | cachep->obj_size = size; |
1da177e4 LT |
1989 | |
1990 | if (flags & SLAB_RED_ZONE) { | |
1991 | /* redzoning only works with word aligned caches */ | |
1992 | align = BYTES_PER_WORD; | |
1993 | ||
1994 | /* add space for red zone words */ | |
3dafccf2 | 1995 | cachep->obj_offset += BYTES_PER_WORD; |
b28a02de | 1996 | size += 2 * BYTES_PER_WORD; |
1da177e4 LT |
1997 | } |
1998 | if (flags & SLAB_STORE_USER) { | |
1999 | /* user store requires word alignment and | |
2000 | * one word storage behind the end of the real | |
2001 | * object. | |
2002 | */ | |
2003 | align = BYTES_PER_WORD; | |
2004 | size += BYTES_PER_WORD; | |
2005 | } | |
2006 | #if FORCED_DEBUG && defined(CONFIG_DEBUG_PAGEALLOC) | |
b28a02de | 2007 | if (size >= malloc_sizes[INDEX_L3 + 1].cs_size |
3dafccf2 MS |
2008 | && cachep->obj_size > cache_line_size() && size < PAGE_SIZE) { |
2009 | cachep->obj_offset += PAGE_SIZE - size; | |
1da177e4 LT |
2010 | size = PAGE_SIZE; |
2011 | } | |
2012 | #endif | |
2013 | #endif | |
2014 | ||
2015 | /* Determine if the slab management is 'on' or 'off' slab. */ | |
b28a02de | 2016 | if (size >= (PAGE_SIZE >> 3)) |
1da177e4 LT |
2017 | /* |
2018 | * Size is large, assume best to place the slab management obj | |
2019 | * off-slab (should allow better packing of objs). | |
2020 | */ | |
2021 | flags |= CFLGS_OFF_SLAB; | |
2022 | ||
2023 | size = ALIGN(size, align); | |
2024 | ||
f78bb8ad | 2025 | left_over = calculate_slab_order(cachep, size, align, flags); |
1da177e4 LT |
2026 | |
2027 | if (!cachep->num) { | |
2028 | printk("kmem_cache_create: couldn't create cache %s.\n", name); | |
2029 | kmem_cache_free(&cache_cache, cachep); | |
2030 | cachep = NULL; | |
4f12bb4f | 2031 | goto oops; |
1da177e4 | 2032 | } |
b28a02de PE |
2033 | slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t) |
2034 | + sizeof(struct slab), align); | |
1da177e4 LT |
2035 | |
2036 | /* | |
2037 | * If the slab has been placed off-slab, and we have enough space then | |
2038 | * move it on-slab. This is at the expense of any extra colouring. | |
2039 | */ | |
2040 | if (flags & CFLGS_OFF_SLAB && left_over >= slab_size) { | |
2041 | flags &= ~CFLGS_OFF_SLAB; | |
2042 | left_over -= slab_size; | |
2043 | } | |
2044 | ||
2045 | if (flags & CFLGS_OFF_SLAB) { | |
2046 | /* really off slab. No need for manual alignment */ | |
b28a02de PE |
2047 | slab_size = |
2048 | cachep->num * sizeof(kmem_bufctl_t) + sizeof(struct slab); | |
1da177e4 LT |
2049 | } |
2050 | ||
2051 | cachep->colour_off = cache_line_size(); | |
2052 | /* Offset must be a multiple of the alignment. */ | |
2053 | if (cachep->colour_off < align) | |
2054 | cachep->colour_off = align; | |
b28a02de | 2055 | cachep->colour = left_over / cachep->colour_off; |
1da177e4 LT |
2056 | cachep->slab_size = slab_size; |
2057 | cachep->flags = flags; | |
2058 | cachep->gfpflags = 0; | |
2059 | if (flags & SLAB_CACHE_DMA) | |
2060 | cachep->gfpflags |= GFP_DMA; | |
3dafccf2 | 2061 | cachep->buffer_size = size; |
1da177e4 LT |
2062 | |
2063 | if (flags & CFLGS_OFF_SLAB) | |
b2d55073 | 2064 | cachep->slabp_cache = kmem_find_general_cachep(slab_size, 0u); |
1da177e4 LT |
2065 | cachep->ctor = ctor; |
2066 | cachep->dtor = dtor; | |
2067 | cachep->name = name; | |
2068 | ||
1da177e4 | 2069 | |
f30cf7d1 | 2070 | setup_cpu_cache(cachep); |
1da177e4 | 2071 | |
1da177e4 LT |
2072 | /* cache setup completed, link it into the list */ |
2073 | list_add(&cachep->next, &cache_chain); | |
a737b3e2 | 2074 | oops: |
1da177e4 LT |
2075 | if (!cachep && (flags & SLAB_PANIC)) |
2076 | panic("kmem_cache_create(): failed to create slab `%s'\n", | |
b28a02de | 2077 | name); |
fc0abb14 | 2078 | mutex_unlock(&cache_chain_mutex); |
f0188f47 | 2079 | unlock_cpu_hotplug(); |
1da177e4 LT |
2080 | return cachep; |
2081 | } | |
2082 | EXPORT_SYMBOL(kmem_cache_create); | |
2083 | ||
2084 | #if DEBUG | |
2085 | static void check_irq_off(void) | |
2086 | { | |
2087 | BUG_ON(!irqs_disabled()); | |
2088 | } | |
2089 | ||
2090 | static void check_irq_on(void) | |
2091 | { | |
2092 | BUG_ON(irqs_disabled()); | |
2093 | } | |
2094 | ||
343e0d7a | 2095 | static void check_spinlock_acquired(struct kmem_cache *cachep) |
1da177e4 LT |
2096 | { |
2097 | #ifdef CONFIG_SMP | |
2098 | check_irq_off(); | |
e498be7d | 2099 | assert_spin_locked(&cachep->nodelists[numa_node_id()]->list_lock); |
1da177e4 LT |
2100 | #endif |
2101 | } | |
e498be7d | 2102 | |
343e0d7a | 2103 | static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) |
e498be7d CL |
2104 | { |
2105 | #ifdef CONFIG_SMP | |
2106 | check_irq_off(); | |
2107 | assert_spin_locked(&cachep->nodelists[node]->list_lock); | |
2108 | #endif | |
2109 | } | |
2110 | ||
1da177e4 LT |
2111 | #else |
2112 | #define check_irq_off() do { } while(0) | |
2113 | #define check_irq_on() do { } while(0) | |
2114 | #define check_spinlock_acquired(x) do { } while(0) | |
e498be7d | 2115 | #define check_spinlock_acquired_node(x, y) do { } while(0) |
1da177e4 LT |
2116 | #endif |
2117 | ||
2118 | /* | |
2119 | * Waits for all CPUs to execute func(). | |
2120 | */ | |
b28a02de | 2121 | static void smp_call_function_all_cpus(void (*func)(void *arg), void *arg) |
1da177e4 LT |
2122 | { |
2123 | check_irq_on(); | |
2124 | preempt_disable(); | |
1da177e4 LT |
2125 | local_irq_disable(); |
2126 | func(arg); | |
2127 | local_irq_enable(); | |
2128 | ||
2129 | if (smp_call_function(func, arg, 1, 1)) | |
2130 | BUG(); | |
2131 | ||
2132 | preempt_enable(); | |
2133 | } | |
2134 | ||
a737b3e2 AM |
2135 | static void drain_array_locked(struct kmem_cache *cachep, |
2136 | struct array_cache *ac, int force, int node); | |
1da177e4 LT |
2137 | |
2138 | static void do_drain(void *arg) | |
2139 | { | |
a737b3e2 | 2140 | struct kmem_cache *cachep = arg; |
1da177e4 | 2141 | struct array_cache *ac; |
ff69416e | 2142 | int node = numa_node_id(); |
1da177e4 LT |
2143 | |
2144 | check_irq_off(); | |
9a2dba4b | 2145 | ac = cpu_cache_get(cachep); |
ff69416e CL |
2146 | spin_lock(&cachep->nodelists[node]->list_lock); |
2147 | free_block(cachep, ac->entry, ac->avail, node); | |
2148 | spin_unlock(&cachep->nodelists[node]->list_lock); | |
1da177e4 LT |
2149 | ac->avail = 0; |
2150 | } | |
2151 | ||
343e0d7a | 2152 | static void drain_cpu_caches(struct kmem_cache *cachep) |
1da177e4 | 2153 | { |
e498be7d CL |
2154 | struct kmem_list3 *l3; |
2155 | int node; | |
2156 | ||
1da177e4 LT |
2157 | smp_call_function_all_cpus(do_drain, cachep); |
2158 | check_irq_on(); | |
b28a02de | 2159 | for_each_online_node(node) { |
e498be7d CL |
2160 | l3 = cachep->nodelists[node]; |
2161 | if (l3) { | |
ca3b9b91 | 2162 | spin_lock_irq(&l3->list_lock); |
e498be7d | 2163 | drain_array_locked(cachep, l3->shared, 1, node); |
ca3b9b91 | 2164 | spin_unlock_irq(&l3->list_lock); |
e498be7d | 2165 | if (l3->alien) |
4484ebf1 | 2166 | drain_alien_cache(cachep, l3->alien); |
e498be7d CL |
2167 | } |
2168 | } | |
1da177e4 LT |
2169 | } |
2170 | ||
343e0d7a | 2171 | static int __node_shrink(struct kmem_cache *cachep, int node) |
1da177e4 LT |
2172 | { |
2173 | struct slab *slabp; | |
e498be7d | 2174 | struct kmem_list3 *l3 = cachep->nodelists[node]; |
1da177e4 LT |
2175 | int ret; |
2176 | ||
e498be7d | 2177 | for (;;) { |
1da177e4 LT |
2178 | struct list_head *p; |
2179 | ||
e498be7d CL |
2180 | p = l3->slabs_free.prev; |
2181 | if (p == &l3->slabs_free) | |
1da177e4 LT |
2182 | break; |
2183 | ||
e498be7d | 2184 | slabp = list_entry(l3->slabs_free.prev, struct slab, list); |
1da177e4 LT |
2185 | #if DEBUG |
2186 | if (slabp->inuse) | |
2187 | BUG(); | |
2188 | #endif | |
2189 | list_del(&slabp->list); | |
2190 | ||
e498be7d CL |
2191 | l3->free_objects -= cachep->num; |
2192 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 2193 | slab_destroy(cachep, slabp); |
e498be7d | 2194 | spin_lock_irq(&l3->list_lock); |
1da177e4 | 2195 | } |
b28a02de | 2196 | ret = !list_empty(&l3->slabs_full) || !list_empty(&l3->slabs_partial); |
1da177e4 LT |
2197 | return ret; |
2198 | } | |
2199 | ||
343e0d7a | 2200 | static int __cache_shrink(struct kmem_cache *cachep) |
e498be7d CL |
2201 | { |
2202 | int ret = 0, i = 0; | |
2203 | struct kmem_list3 *l3; | |
2204 | ||
2205 | drain_cpu_caches(cachep); | |
2206 | ||
2207 | check_irq_on(); | |
2208 | for_each_online_node(i) { | |
2209 | l3 = cachep->nodelists[i]; | |
2210 | if (l3) { | |
2211 | spin_lock_irq(&l3->list_lock); | |
2212 | ret += __node_shrink(cachep, i); | |
2213 | spin_unlock_irq(&l3->list_lock); | |
2214 | } | |
2215 | } | |
2216 | return (ret ? 1 : 0); | |
2217 | } | |
2218 | ||
1da177e4 LT |
2219 | /** |
2220 | * kmem_cache_shrink - Shrink a cache. | |
2221 | * @cachep: The cache to shrink. | |
2222 | * | |
2223 | * Releases as many slabs as possible for a cache. | |
2224 | * To help debugging, a zero exit status indicates all slabs were released. | |
2225 | */ | |
343e0d7a | 2226 | int kmem_cache_shrink(struct kmem_cache *cachep) |
1da177e4 LT |
2227 | { |
2228 | if (!cachep || in_interrupt()) | |
2229 | BUG(); | |
2230 | ||
2231 | return __cache_shrink(cachep); | |
2232 | } | |
2233 | EXPORT_SYMBOL(kmem_cache_shrink); | |
2234 | ||
2235 | /** | |
2236 | * kmem_cache_destroy - delete a cache | |
2237 | * @cachep: the cache to destroy | |
2238 | * | |
343e0d7a | 2239 | * Remove a struct kmem_cache object from the slab cache. |
1da177e4 LT |
2240 | * Returns 0 on success. |
2241 | * | |
2242 | * It is expected this function will be called by a module when it is | |
2243 | * unloaded. This will remove the cache completely, and avoid a duplicate | |
2244 | * cache being allocated each time a module is loaded and unloaded, if the | |
2245 | * module doesn't have persistent in-kernel storage across loads and unloads. | |
2246 | * | |
2247 | * The cache must be empty before calling this function. | |
2248 | * | |
2249 | * The caller must guarantee that noone will allocate memory from the cache | |
2250 | * during the kmem_cache_destroy(). | |
2251 | */ | |
343e0d7a | 2252 | int kmem_cache_destroy(struct kmem_cache *cachep) |
1da177e4 LT |
2253 | { |
2254 | int i; | |
e498be7d | 2255 | struct kmem_list3 *l3; |
1da177e4 LT |
2256 | |
2257 | if (!cachep || in_interrupt()) | |
2258 | BUG(); | |
2259 | ||
2260 | /* Don't let CPUs to come and go */ | |
2261 | lock_cpu_hotplug(); | |
2262 | ||
2263 | /* Find the cache in the chain of caches. */ | |
fc0abb14 | 2264 | mutex_lock(&cache_chain_mutex); |
1da177e4 LT |
2265 | /* |
2266 | * the chain is never empty, cache_cache is never destroyed | |
2267 | */ | |
2268 | list_del(&cachep->next); | |
fc0abb14 | 2269 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
2270 | |
2271 | if (__cache_shrink(cachep)) { | |
2272 | slab_error(cachep, "Can't free all objects"); | |
fc0abb14 | 2273 | mutex_lock(&cache_chain_mutex); |
b28a02de | 2274 | list_add(&cachep->next, &cache_chain); |
fc0abb14 | 2275 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
2276 | unlock_cpu_hotplug(); |
2277 | return 1; | |
2278 | } | |
2279 | ||
2280 | if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) | |
fbd568a3 | 2281 | synchronize_rcu(); |
1da177e4 | 2282 | |
e498be7d | 2283 | for_each_online_cpu(i) |
b28a02de | 2284 | kfree(cachep->array[i]); |
1da177e4 LT |
2285 | |
2286 | /* NUMA: free the list3 structures */ | |
e498be7d | 2287 | for_each_online_node(i) { |
a737b3e2 AM |
2288 | l3 = cachep->nodelists[i]; |
2289 | if (l3) { | |
e498be7d CL |
2290 | kfree(l3->shared); |
2291 | free_alien_cache(l3->alien); | |
2292 | kfree(l3); | |
2293 | } | |
2294 | } | |
1da177e4 | 2295 | kmem_cache_free(&cache_cache, cachep); |
1da177e4 | 2296 | unlock_cpu_hotplug(); |
1da177e4 LT |
2297 | return 0; |
2298 | } | |
2299 | EXPORT_SYMBOL(kmem_cache_destroy); | |
2300 | ||
2301 | /* Get the memory for a slab management obj. */ | |
343e0d7a | 2302 | static struct slab *alloc_slabmgmt(struct kmem_cache *cachep, void *objp, |
b28a02de | 2303 | int colour_off, gfp_t local_flags) |
1da177e4 LT |
2304 | { |
2305 | struct slab *slabp; | |
b28a02de | 2306 | |
1da177e4 LT |
2307 | if (OFF_SLAB(cachep)) { |
2308 | /* Slab management obj is off-slab. */ | |
2309 | slabp = kmem_cache_alloc(cachep->slabp_cache, local_flags); | |
2310 | if (!slabp) | |
2311 | return NULL; | |
2312 | } else { | |
b28a02de | 2313 | slabp = objp + colour_off; |
1da177e4 LT |
2314 | colour_off += cachep->slab_size; |
2315 | } | |
2316 | slabp->inuse = 0; | |
2317 | slabp->colouroff = colour_off; | |
b28a02de | 2318 | slabp->s_mem = objp + colour_off; |
1da177e4 LT |
2319 | return slabp; |
2320 | } | |
2321 | ||
2322 | static inline kmem_bufctl_t *slab_bufctl(struct slab *slabp) | |
2323 | { | |
b28a02de | 2324 | return (kmem_bufctl_t *) (slabp + 1); |
1da177e4 LT |
2325 | } |
2326 | ||
343e0d7a | 2327 | static void cache_init_objs(struct kmem_cache *cachep, |
b28a02de | 2328 | struct slab *slabp, unsigned long ctor_flags) |
1da177e4 LT |
2329 | { |
2330 | int i; | |
2331 | ||
2332 | for (i = 0; i < cachep->num; i++) { | |
8fea4e96 | 2333 | void *objp = index_to_obj(cachep, slabp, i); |
1da177e4 LT |
2334 | #if DEBUG |
2335 | /* need to poison the objs? */ | |
2336 | if (cachep->flags & SLAB_POISON) | |
2337 | poison_obj(cachep, objp, POISON_FREE); | |
2338 | if (cachep->flags & SLAB_STORE_USER) | |
2339 | *dbg_userword(cachep, objp) = NULL; | |
2340 | ||
2341 | if (cachep->flags & SLAB_RED_ZONE) { | |
2342 | *dbg_redzone1(cachep, objp) = RED_INACTIVE; | |
2343 | *dbg_redzone2(cachep, objp) = RED_INACTIVE; | |
2344 | } | |
2345 | /* | |
a737b3e2 AM |
2346 | * Constructors are not allowed to allocate memory from the same |
2347 | * cache which they are a constructor for. Otherwise, deadlock. | |
2348 | * They must also be threaded. | |
1da177e4 LT |
2349 | */ |
2350 | if (cachep->ctor && !(cachep->flags & SLAB_POISON)) | |
3dafccf2 | 2351 | cachep->ctor(objp + obj_offset(cachep), cachep, |
b28a02de | 2352 | ctor_flags); |
1da177e4 LT |
2353 | |
2354 | if (cachep->flags & SLAB_RED_ZONE) { | |
2355 | if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) | |
2356 | slab_error(cachep, "constructor overwrote the" | |
b28a02de | 2357 | " end of an object"); |
1da177e4 LT |
2358 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) |
2359 | slab_error(cachep, "constructor overwrote the" | |
b28a02de | 2360 | " start of an object"); |
1da177e4 | 2361 | } |
a737b3e2 AM |
2362 | if ((cachep->buffer_size % PAGE_SIZE) == 0 && |
2363 | OFF_SLAB(cachep) && cachep->flags & SLAB_POISON) | |
b28a02de | 2364 | kernel_map_pages(virt_to_page(objp), |
3dafccf2 | 2365 | cachep->buffer_size / PAGE_SIZE, 0); |
1da177e4 LT |
2366 | #else |
2367 | if (cachep->ctor) | |
2368 | cachep->ctor(objp, cachep, ctor_flags); | |
2369 | #endif | |
b28a02de | 2370 | slab_bufctl(slabp)[i] = i + 1; |
1da177e4 | 2371 | } |
b28a02de | 2372 | slab_bufctl(slabp)[i - 1] = BUFCTL_END; |
1da177e4 LT |
2373 | slabp->free = 0; |
2374 | } | |
2375 | ||
343e0d7a | 2376 | static void kmem_flagcheck(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 | 2377 | { |
a737b3e2 AM |
2378 | if (flags & SLAB_DMA) |
2379 | BUG_ON(!(cachep->gfpflags & GFP_DMA)); | |
2380 | else | |
2381 | BUG_ON(cachep->gfpflags & GFP_DMA); | |
1da177e4 LT |
2382 | } |
2383 | ||
a737b3e2 AM |
2384 | static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp, |
2385 | int nodeid) | |
78d382d7 | 2386 | { |
8fea4e96 | 2387 | void *objp = index_to_obj(cachep, slabp, slabp->free); |
78d382d7 MD |
2388 | kmem_bufctl_t next; |
2389 | ||
2390 | slabp->inuse++; | |
2391 | next = slab_bufctl(slabp)[slabp->free]; | |
2392 | #if DEBUG | |
2393 | slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE; | |
2394 | WARN_ON(slabp->nodeid != nodeid); | |
2395 | #endif | |
2396 | slabp->free = next; | |
2397 | ||
2398 | return objp; | |
2399 | } | |
2400 | ||
a737b3e2 AM |
2401 | static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp, |
2402 | void *objp, int nodeid) | |
78d382d7 | 2403 | { |
8fea4e96 | 2404 | unsigned int objnr = obj_to_index(cachep, slabp, objp); |
78d382d7 MD |
2405 | |
2406 | #if DEBUG | |
2407 | /* Verify that the slab belongs to the intended node */ | |
2408 | WARN_ON(slabp->nodeid != nodeid); | |
2409 | ||
2410 | if (slab_bufctl(slabp)[objnr] != BUFCTL_FREE) { | |
2411 | printk(KERN_ERR "slab: double free detected in cache " | |
a737b3e2 | 2412 | "'%s', objp %p\n", cachep->name, objp); |
78d382d7 MD |
2413 | BUG(); |
2414 | } | |
2415 | #endif | |
2416 | slab_bufctl(slabp)[objnr] = slabp->free; | |
2417 | slabp->free = objnr; | |
2418 | slabp->inuse--; | |
2419 | } | |
2420 | ||
a737b3e2 AM |
2421 | static void set_slab_attr(struct kmem_cache *cachep, struct slab *slabp, |
2422 | void *objp) | |
1da177e4 LT |
2423 | { |
2424 | int i; | |
2425 | struct page *page; | |
2426 | ||
2427 | /* Nasty!!!!!! I hope this is OK. */ | |
2428 | i = 1 << cachep->gfporder; | |
2429 | page = virt_to_page(objp); | |
2430 | do { | |
065d41cb PE |
2431 | page_set_cache(page, cachep); |
2432 | page_set_slab(page, slabp); | |
1da177e4 LT |
2433 | page++; |
2434 | } while (--i); | |
2435 | } | |
2436 | ||
2437 | /* | |
2438 | * Grow (by 1) the number of slabs within a cache. This is called by | |
2439 | * kmem_cache_alloc() when there are no active objs left in a cache. | |
2440 | */ | |
343e0d7a | 2441 | static int cache_grow(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 | 2442 | { |
b28a02de PE |
2443 | struct slab *slabp; |
2444 | void *objp; | |
2445 | size_t offset; | |
2446 | gfp_t local_flags; | |
2447 | unsigned long ctor_flags; | |
e498be7d | 2448 | struct kmem_list3 *l3; |
1da177e4 | 2449 | |
a737b3e2 AM |
2450 | /* |
2451 | * Be lazy and only check for valid flags here, keeping it out of the | |
2452 | * critical path in kmem_cache_alloc(). | |
1da177e4 | 2453 | */ |
b28a02de | 2454 | if (flags & ~(SLAB_DMA | SLAB_LEVEL_MASK | SLAB_NO_GROW)) |
1da177e4 LT |
2455 | BUG(); |
2456 | if (flags & SLAB_NO_GROW) | |
2457 | return 0; | |
2458 | ||
2459 | ctor_flags = SLAB_CTOR_CONSTRUCTOR; | |
2460 | local_flags = (flags & SLAB_LEVEL_MASK); | |
2461 | if (!(local_flags & __GFP_WAIT)) | |
2462 | /* | |
2463 | * Not allowed to sleep. Need to tell a constructor about | |
2464 | * this - it might need to know... | |
2465 | */ | |
2466 | ctor_flags |= SLAB_CTOR_ATOMIC; | |
2467 | ||
2e1217cf | 2468 | /* Take the l3 list lock to change the colour_next on this node */ |
1da177e4 | 2469 | check_irq_off(); |
2e1217cf RT |
2470 | l3 = cachep->nodelists[nodeid]; |
2471 | spin_lock(&l3->list_lock); | |
1da177e4 LT |
2472 | |
2473 | /* Get colour for the slab, and cal the next value. */ | |
2e1217cf RT |
2474 | offset = l3->colour_next; |
2475 | l3->colour_next++; | |
2476 | if (l3->colour_next >= cachep->colour) | |
2477 | l3->colour_next = 0; | |
2478 | spin_unlock(&l3->list_lock); | |
1da177e4 | 2479 | |
2e1217cf | 2480 | offset *= cachep->colour_off; |
1da177e4 LT |
2481 | |
2482 | if (local_flags & __GFP_WAIT) | |
2483 | local_irq_enable(); | |
2484 | ||
2485 | /* | |
2486 | * The test for missing atomic flag is performed here, rather than | |
2487 | * the more obvious place, simply to reduce the critical path length | |
2488 | * in kmem_cache_alloc(). If a caller is seriously mis-behaving they | |
2489 | * will eventually be caught here (where it matters). | |
2490 | */ | |
2491 | kmem_flagcheck(cachep, flags); | |
2492 | ||
a737b3e2 AM |
2493 | /* |
2494 | * Get mem for the objs. Attempt to allocate a physical page from | |
2495 | * 'nodeid'. | |
e498be7d | 2496 | */ |
a737b3e2 AM |
2497 | objp = kmem_getpages(cachep, flags, nodeid); |
2498 | if (!objp) | |
1da177e4 LT |
2499 | goto failed; |
2500 | ||
2501 | /* Get slab management. */ | |
a737b3e2 AM |
2502 | slabp = alloc_slabmgmt(cachep, objp, offset, local_flags); |
2503 | if (!slabp) | |
1da177e4 LT |
2504 | goto opps1; |
2505 | ||
e498be7d | 2506 | slabp->nodeid = nodeid; |
1da177e4 LT |
2507 | set_slab_attr(cachep, slabp, objp); |
2508 | ||
2509 | cache_init_objs(cachep, slabp, ctor_flags); | |
2510 | ||
2511 | if (local_flags & __GFP_WAIT) | |
2512 | local_irq_disable(); | |
2513 | check_irq_off(); | |
e498be7d | 2514 | spin_lock(&l3->list_lock); |
1da177e4 LT |
2515 | |
2516 | /* Make slab active. */ | |
e498be7d | 2517 | list_add_tail(&slabp->list, &(l3->slabs_free)); |
1da177e4 | 2518 | STATS_INC_GROWN(cachep); |
e498be7d CL |
2519 | l3->free_objects += cachep->num; |
2520 | spin_unlock(&l3->list_lock); | |
1da177e4 | 2521 | return 1; |
a737b3e2 | 2522 | opps1: |
1da177e4 | 2523 | kmem_freepages(cachep, objp); |
a737b3e2 | 2524 | failed: |
1da177e4 LT |
2525 | if (local_flags & __GFP_WAIT) |
2526 | local_irq_disable(); | |
2527 | return 0; | |
2528 | } | |
2529 | ||
2530 | #if DEBUG | |
2531 | ||
2532 | /* | |
2533 | * Perform extra freeing checks: | |
2534 | * - detect bad pointers. | |
2535 | * - POISON/RED_ZONE checking | |
2536 | * - destructor calls, for caches with POISON+dtor | |
2537 | */ | |
2538 | static void kfree_debugcheck(const void *objp) | |
2539 | { | |
2540 | struct page *page; | |
2541 | ||
2542 | if (!virt_addr_valid(objp)) { | |
2543 | printk(KERN_ERR "kfree_debugcheck: out of range ptr %lxh.\n", | |
b28a02de PE |
2544 | (unsigned long)objp); |
2545 | BUG(); | |
1da177e4 LT |
2546 | } |
2547 | page = virt_to_page(objp); | |
2548 | if (!PageSlab(page)) { | |
b28a02de PE |
2549 | printk(KERN_ERR "kfree_debugcheck: bad ptr %lxh.\n", |
2550 | (unsigned long)objp); | |
1da177e4 LT |
2551 | BUG(); |
2552 | } | |
2553 | } | |
2554 | ||
343e0d7a | 2555 | static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp, |
b28a02de | 2556 | void *caller) |
1da177e4 LT |
2557 | { |
2558 | struct page *page; | |
2559 | unsigned int objnr; | |
2560 | struct slab *slabp; | |
2561 | ||
3dafccf2 | 2562 | objp -= obj_offset(cachep); |
1da177e4 LT |
2563 | kfree_debugcheck(objp); |
2564 | page = virt_to_page(objp); | |
2565 | ||
065d41cb | 2566 | if (page_get_cache(page) != cachep) { |
a737b3e2 AM |
2567 | printk(KERN_ERR "mismatch in kmem_cache_free: expected " |
2568 | "cache %p, got %p\n", | |
b28a02de | 2569 | page_get_cache(page), cachep); |
1da177e4 | 2570 | printk(KERN_ERR "%p is %s.\n", cachep, cachep->name); |
b28a02de PE |
2571 | printk(KERN_ERR "%p is %s.\n", page_get_cache(page), |
2572 | page_get_cache(page)->name); | |
1da177e4 LT |
2573 | WARN_ON(1); |
2574 | } | |
065d41cb | 2575 | slabp = page_get_slab(page); |
1da177e4 LT |
2576 | |
2577 | if (cachep->flags & SLAB_RED_ZONE) { | |
a737b3e2 AM |
2578 | if (*dbg_redzone1(cachep, objp) != RED_ACTIVE || |
2579 | *dbg_redzone2(cachep, objp) != RED_ACTIVE) { | |
2580 | slab_error(cachep, "double free, or memory outside" | |
2581 | " object was overwritten"); | |
2582 | printk(KERN_ERR "%p: redzone 1:0x%lx, " | |
2583 | "redzone 2:0x%lx.\n", | |
b28a02de PE |
2584 | objp, *dbg_redzone1(cachep, objp), |
2585 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
2586 | } |
2587 | *dbg_redzone1(cachep, objp) = RED_INACTIVE; | |
2588 | *dbg_redzone2(cachep, objp) = RED_INACTIVE; | |
2589 | } | |
2590 | if (cachep->flags & SLAB_STORE_USER) | |
2591 | *dbg_userword(cachep, objp) = caller; | |
2592 | ||
8fea4e96 | 2593 | objnr = obj_to_index(cachep, slabp, objp); |
1da177e4 LT |
2594 | |
2595 | BUG_ON(objnr >= cachep->num); | |
8fea4e96 | 2596 | BUG_ON(objp != index_to_obj(cachep, slabp, objnr)); |
1da177e4 LT |
2597 | |
2598 | if (cachep->flags & SLAB_DEBUG_INITIAL) { | |
a737b3e2 AM |
2599 | /* |
2600 | * Need to call the slab's constructor so the caller can | |
2601 | * perform a verify of its state (debugging). Called without | |
2602 | * the cache-lock held. | |
1da177e4 | 2603 | */ |
3dafccf2 | 2604 | cachep->ctor(objp + obj_offset(cachep), |
b28a02de | 2605 | cachep, SLAB_CTOR_CONSTRUCTOR | SLAB_CTOR_VERIFY); |
1da177e4 LT |
2606 | } |
2607 | if (cachep->flags & SLAB_POISON && cachep->dtor) { | |
2608 | /* we want to cache poison the object, | |
2609 | * call the destruction callback | |
2610 | */ | |
3dafccf2 | 2611 | cachep->dtor(objp + obj_offset(cachep), cachep, 0); |
1da177e4 LT |
2612 | } |
2613 | if (cachep->flags & SLAB_POISON) { | |
2614 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
a737b3e2 | 2615 | if ((cachep->buffer_size % PAGE_SIZE)==0 && OFF_SLAB(cachep)) { |
1da177e4 | 2616 | store_stackinfo(cachep, objp, (unsigned long)caller); |
b28a02de | 2617 | kernel_map_pages(virt_to_page(objp), |
3dafccf2 | 2618 | cachep->buffer_size / PAGE_SIZE, 0); |
1da177e4 LT |
2619 | } else { |
2620 | poison_obj(cachep, objp, POISON_FREE); | |
2621 | } | |
2622 | #else | |
2623 | poison_obj(cachep, objp, POISON_FREE); | |
2624 | #endif | |
2625 | } | |
2626 | return objp; | |
2627 | } | |
2628 | ||
343e0d7a | 2629 | static void check_slabp(struct kmem_cache *cachep, struct slab *slabp) |
1da177e4 LT |
2630 | { |
2631 | kmem_bufctl_t i; | |
2632 | int entries = 0; | |
b28a02de | 2633 | |
1da177e4 LT |
2634 | /* Check slab's freelist to see if this obj is there. */ |
2635 | for (i = slabp->free; i != BUFCTL_END; i = slab_bufctl(slabp)[i]) { | |
2636 | entries++; | |
2637 | if (entries > cachep->num || i >= cachep->num) | |
2638 | goto bad; | |
2639 | } | |
2640 | if (entries != cachep->num - slabp->inuse) { | |
a737b3e2 AM |
2641 | bad: |
2642 | printk(KERN_ERR "slab: Internal list corruption detected in " | |
2643 | "cache '%s'(%d), slabp %p(%d). Hexdump:\n", | |
2644 | cachep->name, cachep->num, slabp, slabp->inuse); | |
b28a02de | 2645 | for (i = 0; |
264132bc | 2646 | i < sizeof(*slabp) + cachep->num * sizeof(kmem_bufctl_t); |
b28a02de | 2647 | i++) { |
a737b3e2 | 2648 | if (i % 16 == 0) |
1da177e4 | 2649 | printk("\n%03x:", i); |
b28a02de | 2650 | printk(" %02x", ((unsigned char *)slabp)[i]); |
1da177e4 LT |
2651 | } |
2652 | printk("\n"); | |
2653 | BUG(); | |
2654 | } | |
2655 | } | |
2656 | #else | |
2657 | #define kfree_debugcheck(x) do { } while(0) | |
2658 | #define cache_free_debugcheck(x,objp,z) (objp) | |
2659 | #define check_slabp(x,y) do { } while(0) | |
2660 | #endif | |
2661 | ||
343e0d7a | 2662 | static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 LT |
2663 | { |
2664 | int batchcount; | |
2665 | struct kmem_list3 *l3; | |
2666 | struct array_cache *ac; | |
2667 | ||
2668 | check_irq_off(); | |
9a2dba4b | 2669 | ac = cpu_cache_get(cachep); |
a737b3e2 | 2670 | retry: |
1da177e4 LT |
2671 | batchcount = ac->batchcount; |
2672 | if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { | |
a737b3e2 AM |
2673 | /* |
2674 | * If there was little recent activity on this cache, then | |
2675 | * perform only a partial refill. Otherwise we could generate | |
2676 | * refill bouncing. | |
1da177e4 LT |
2677 | */ |
2678 | batchcount = BATCHREFILL_LIMIT; | |
2679 | } | |
e498be7d CL |
2680 | l3 = cachep->nodelists[numa_node_id()]; |
2681 | ||
2682 | BUG_ON(ac->avail > 0 || !l3); | |
2683 | spin_lock(&l3->list_lock); | |
1da177e4 | 2684 | |
1da177e4 LT |
2685 | if (l3->shared) { |
2686 | struct array_cache *shared_array = l3->shared; | |
2687 | if (shared_array->avail) { | |
2688 | if (batchcount > shared_array->avail) | |
2689 | batchcount = shared_array->avail; | |
2690 | shared_array->avail -= batchcount; | |
2691 | ac->avail = batchcount; | |
e498be7d | 2692 | memcpy(ac->entry, |
b28a02de PE |
2693 | &(shared_array->entry[shared_array->avail]), |
2694 | sizeof(void *) * batchcount); | |
1da177e4 LT |
2695 | shared_array->touched = 1; |
2696 | goto alloc_done; | |
2697 | } | |
2698 | } | |
2699 | while (batchcount > 0) { | |
2700 | struct list_head *entry; | |
2701 | struct slab *slabp; | |
2702 | /* Get slab alloc is to come from. */ | |
2703 | entry = l3->slabs_partial.next; | |
2704 | if (entry == &l3->slabs_partial) { | |
2705 | l3->free_touched = 1; | |
2706 | entry = l3->slabs_free.next; | |
2707 | if (entry == &l3->slabs_free) | |
2708 | goto must_grow; | |
2709 | } | |
2710 | ||
2711 | slabp = list_entry(entry, struct slab, list); | |
2712 | check_slabp(cachep, slabp); | |
2713 | check_spinlock_acquired(cachep); | |
2714 | while (slabp->inuse < cachep->num && batchcount--) { | |
1da177e4 LT |
2715 | STATS_INC_ALLOCED(cachep); |
2716 | STATS_INC_ACTIVE(cachep); | |
2717 | STATS_SET_HIGH(cachep); | |
2718 | ||
78d382d7 MD |
2719 | ac->entry[ac->avail++] = slab_get_obj(cachep, slabp, |
2720 | numa_node_id()); | |
1da177e4 LT |
2721 | } |
2722 | check_slabp(cachep, slabp); | |
2723 | ||
2724 | /* move slabp to correct slabp list: */ | |
2725 | list_del(&slabp->list); | |
2726 | if (slabp->free == BUFCTL_END) | |
2727 | list_add(&slabp->list, &l3->slabs_full); | |
2728 | else | |
2729 | list_add(&slabp->list, &l3->slabs_partial); | |
2730 | } | |
2731 | ||
a737b3e2 | 2732 | must_grow: |
1da177e4 | 2733 | l3->free_objects -= ac->avail; |
a737b3e2 | 2734 | alloc_done: |
e498be7d | 2735 | spin_unlock(&l3->list_lock); |
1da177e4 LT |
2736 | |
2737 | if (unlikely(!ac->avail)) { | |
2738 | int x; | |
e498be7d CL |
2739 | x = cache_grow(cachep, flags, numa_node_id()); |
2740 | ||
a737b3e2 | 2741 | /* cache_grow can reenable interrupts, then ac could change. */ |
9a2dba4b | 2742 | ac = cpu_cache_get(cachep); |
a737b3e2 | 2743 | if (!x && ac->avail == 0) /* no objects in sight? abort */ |
1da177e4 LT |
2744 | return NULL; |
2745 | ||
a737b3e2 | 2746 | if (!ac->avail) /* objects refilled by interrupt? */ |
1da177e4 LT |
2747 | goto retry; |
2748 | } | |
2749 | ac->touched = 1; | |
e498be7d | 2750 | return ac->entry[--ac->avail]; |
1da177e4 LT |
2751 | } |
2752 | ||
a737b3e2 AM |
2753 | static inline void cache_alloc_debugcheck_before(struct kmem_cache *cachep, |
2754 | gfp_t flags) | |
1da177e4 LT |
2755 | { |
2756 | might_sleep_if(flags & __GFP_WAIT); | |
2757 | #if DEBUG | |
2758 | kmem_flagcheck(cachep, flags); | |
2759 | #endif | |
2760 | } | |
2761 | ||
2762 | #if DEBUG | |
a737b3e2 AM |
2763 | static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, |
2764 | gfp_t flags, void *objp, void *caller) | |
1da177e4 | 2765 | { |
b28a02de | 2766 | if (!objp) |
1da177e4 | 2767 | return objp; |
b28a02de | 2768 | if (cachep->flags & SLAB_POISON) { |
1da177e4 | 2769 | #ifdef CONFIG_DEBUG_PAGEALLOC |
3dafccf2 | 2770 | if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) |
b28a02de | 2771 | kernel_map_pages(virt_to_page(objp), |
3dafccf2 | 2772 | cachep->buffer_size / PAGE_SIZE, 1); |
1da177e4 LT |
2773 | else |
2774 | check_poison_obj(cachep, objp); | |
2775 | #else | |
2776 | check_poison_obj(cachep, objp); | |
2777 | #endif | |
2778 | poison_obj(cachep, objp, POISON_INUSE); | |
2779 | } | |
2780 | if (cachep->flags & SLAB_STORE_USER) | |
2781 | *dbg_userword(cachep, objp) = caller; | |
2782 | ||
2783 | if (cachep->flags & SLAB_RED_ZONE) { | |
a737b3e2 AM |
2784 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE || |
2785 | *dbg_redzone2(cachep, objp) != RED_INACTIVE) { | |
2786 | slab_error(cachep, "double free, or memory outside" | |
2787 | " object was overwritten"); | |
b28a02de | 2788 | printk(KERN_ERR |
a737b3e2 AM |
2789 | "%p: redzone 1:0x%lx, redzone 2:0x%lx\n", |
2790 | objp, *dbg_redzone1(cachep, objp), | |
2791 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
2792 | } |
2793 | *dbg_redzone1(cachep, objp) = RED_ACTIVE; | |
2794 | *dbg_redzone2(cachep, objp) = RED_ACTIVE; | |
2795 | } | |
3dafccf2 | 2796 | objp += obj_offset(cachep); |
1da177e4 | 2797 | if (cachep->ctor && cachep->flags & SLAB_POISON) { |
b28a02de | 2798 | unsigned long ctor_flags = SLAB_CTOR_CONSTRUCTOR; |
1da177e4 LT |
2799 | |
2800 | if (!(flags & __GFP_WAIT)) | |
2801 | ctor_flags |= SLAB_CTOR_ATOMIC; | |
2802 | ||
2803 | cachep->ctor(objp, cachep, ctor_flags); | |
b28a02de | 2804 | } |
1da177e4 LT |
2805 | return objp; |
2806 | } | |
2807 | #else | |
2808 | #define cache_alloc_debugcheck_after(a,b,objp,d) (objp) | |
2809 | #endif | |
2810 | ||
343e0d7a | 2811 | static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 | 2812 | { |
b28a02de | 2813 | void *objp; |
1da177e4 LT |
2814 | struct array_cache *ac; |
2815 | ||
dc85da15 | 2816 | #ifdef CONFIG_NUMA |
86c562a9 | 2817 | if (unlikely(current->mempolicy && !in_interrupt())) { |
dc85da15 CL |
2818 | int nid = slab_node(current->mempolicy); |
2819 | ||
2820 | if (nid != numa_node_id()) | |
2821 | return __cache_alloc_node(cachep, flags, nid); | |
2822 | } | |
2823 | #endif | |
2824 | ||
5c382300 | 2825 | check_irq_off(); |
9a2dba4b | 2826 | ac = cpu_cache_get(cachep); |
1da177e4 LT |
2827 | if (likely(ac->avail)) { |
2828 | STATS_INC_ALLOCHIT(cachep); | |
2829 | ac->touched = 1; | |
e498be7d | 2830 | objp = ac->entry[--ac->avail]; |
1da177e4 LT |
2831 | } else { |
2832 | STATS_INC_ALLOCMISS(cachep); | |
2833 | objp = cache_alloc_refill(cachep, flags); | |
2834 | } | |
5c382300 AK |
2835 | return objp; |
2836 | } | |
2837 | ||
a737b3e2 AM |
2838 | static __always_inline void *__cache_alloc(struct kmem_cache *cachep, |
2839 | gfp_t flags, void *caller) | |
5c382300 AK |
2840 | { |
2841 | unsigned long save_flags; | |
b28a02de | 2842 | void *objp; |
5c382300 AK |
2843 | |
2844 | cache_alloc_debugcheck_before(cachep, flags); | |
2845 | ||
2846 | local_irq_save(save_flags); | |
2847 | objp = ____cache_alloc(cachep, flags); | |
1da177e4 | 2848 | local_irq_restore(save_flags); |
34342e86 | 2849 | objp = cache_alloc_debugcheck_after(cachep, flags, objp, |
7fd6b141 | 2850 | caller); |
34342e86 | 2851 | prefetchw(objp); |
1da177e4 LT |
2852 | return objp; |
2853 | } | |
2854 | ||
e498be7d CL |
2855 | #ifdef CONFIG_NUMA |
2856 | /* | |
2857 | * A interface to enable slab creation on nodeid | |
1da177e4 | 2858 | */ |
a737b3e2 AM |
2859 | static void *__cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, |
2860 | int nodeid) | |
e498be7d CL |
2861 | { |
2862 | struct list_head *entry; | |
b28a02de PE |
2863 | struct slab *slabp; |
2864 | struct kmem_list3 *l3; | |
2865 | void *obj; | |
b28a02de PE |
2866 | int x; |
2867 | ||
2868 | l3 = cachep->nodelists[nodeid]; | |
2869 | BUG_ON(!l3); | |
2870 | ||
a737b3e2 | 2871 | retry: |
ca3b9b91 | 2872 | check_irq_off(); |
b28a02de PE |
2873 | spin_lock(&l3->list_lock); |
2874 | entry = l3->slabs_partial.next; | |
2875 | if (entry == &l3->slabs_partial) { | |
2876 | l3->free_touched = 1; | |
2877 | entry = l3->slabs_free.next; | |
2878 | if (entry == &l3->slabs_free) | |
2879 | goto must_grow; | |
2880 | } | |
2881 | ||
2882 | slabp = list_entry(entry, struct slab, list); | |
2883 | check_spinlock_acquired_node(cachep, nodeid); | |
2884 | check_slabp(cachep, slabp); | |
2885 | ||
2886 | STATS_INC_NODEALLOCS(cachep); | |
2887 | STATS_INC_ACTIVE(cachep); | |
2888 | STATS_SET_HIGH(cachep); | |
2889 | ||
2890 | BUG_ON(slabp->inuse == cachep->num); | |
2891 | ||
78d382d7 | 2892 | obj = slab_get_obj(cachep, slabp, nodeid); |
b28a02de PE |
2893 | check_slabp(cachep, slabp); |
2894 | l3->free_objects--; | |
2895 | /* move slabp to correct slabp list: */ | |
2896 | list_del(&slabp->list); | |
2897 | ||
a737b3e2 | 2898 | if (slabp->free == BUFCTL_END) |
b28a02de | 2899 | list_add(&slabp->list, &l3->slabs_full); |
a737b3e2 | 2900 | else |
b28a02de | 2901 | list_add(&slabp->list, &l3->slabs_partial); |
e498be7d | 2902 | |
b28a02de PE |
2903 | spin_unlock(&l3->list_lock); |
2904 | goto done; | |
e498be7d | 2905 | |
a737b3e2 | 2906 | must_grow: |
b28a02de PE |
2907 | spin_unlock(&l3->list_lock); |
2908 | x = cache_grow(cachep, flags, nodeid); | |
1da177e4 | 2909 | |
b28a02de PE |
2910 | if (!x) |
2911 | return NULL; | |
e498be7d | 2912 | |
b28a02de | 2913 | goto retry; |
a737b3e2 | 2914 | done: |
b28a02de | 2915 | return obj; |
e498be7d CL |
2916 | } |
2917 | #endif | |
2918 | ||
2919 | /* | |
2920 | * Caller needs to acquire correct kmem_list's list_lock | |
2921 | */ | |
343e0d7a | 2922 | static void free_block(struct kmem_cache *cachep, void **objpp, int nr_objects, |
b28a02de | 2923 | int node) |
1da177e4 LT |
2924 | { |
2925 | int i; | |
e498be7d | 2926 | struct kmem_list3 *l3; |
1da177e4 LT |
2927 | |
2928 | for (i = 0; i < nr_objects; i++) { | |
2929 | void *objp = objpp[i]; | |
2930 | struct slab *slabp; | |
1da177e4 | 2931 | |
6ed5eb22 | 2932 | slabp = virt_to_slab(objp); |
ff69416e | 2933 | l3 = cachep->nodelists[node]; |
1da177e4 | 2934 | list_del(&slabp->list); |
ff69416e | 2935 | check_spinlock_acquired_node(cachep, node); |
1da177e4 | 2936 | check_slabp(cachep, slabp); |
78d382d7 | 2937 | slab_put_obj(cachep, slabp, objp, node); |
1da177e4 | 2938 | STATS_DEC_ACTIVE(cachep); |
e498be7d | 2939 | l3->free_objects++; |
1da177e4 LT |
2940 | check_slabp(cachep, slabp); |
2941 | ||
2942 | /* fixup slab chains */ | |
2943 | if (slabp->inuse == 0) { | |
e498be7d CL |
2944 | if (l3->free_objects > l3->free_limit) { |
2945 | l3->free_objects -= cachep->num; | |
1da177e4 LT |
2946 | slab_destroy(cachep, slabp); |
2947 | } else { | |
e498be7d | 2948 | list_add(&slabp->list, &l3->slabs_free); |
1da177e4 LT |
2949 | } |
2950 | } else { | |
2951 | /* Unconditionally move a slab to the end of the | |
2952 | * partial list on free - maximum time for the | |
2953 | * other objects to be freed, too. | |
2954 | */ | |
e498be7d | 2955 | list_add_tail(&slabp->list, &l3->slabs_partial); |
1da177e4 LT |
2956 | } |
2957 | } | |
2958 | } | |
2959 | ||
343e0d7a | 2960 | static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) |
1da177e4 LT |
2961 | { |
2962 | int batchcount; | |
e498be7d | 2963 | struct kmem_list3 *l3; |
ff69416e | 2964 | int node = numa_node_id(); |
1da177e4 LT |
2965 | |
2966 | batchcount = ac->batchcount; | |
2967 | #if DEBUG | |
2968 | BUG_ON(!batchcount || batchcount > ac->avail); | |
2969 | #endif | |
2970 | check_irq_off(); | |
ff69416e | 2971 | l3 = cachep->nodelists[node]; |
e498be7d CL |
2972 | spin_lock(&l3->list_lock); |
2973 | if (l3->shared) { | |
2974 | struct array_cache *shared_array = l3->shared; | |
b28a02de | 2975 | int max = shared_array->limit - shared_array->avail; |
1da177e4 LT |
2976 | if (max) { |
2977 | if (batchcount > max) | |
2978 | batchcount = max; | |
e498be7d | 2979 | memcpy(&(shared_array->entry[shared_array->avail]), |
b28a02de | 2980 | ac->entry, sizeof(void *) * batchcount); |
1da177e4 LT |
2981 | shared_array->avail += batchcount; |
2982 | goto free_done; | |
2983 | } | |
2984 | } | |
2985 | ||
ff69416e | 2986 | free_block(cachep, ac->entry, batchcount, node); |
a737b3e2 | 2987 | free_done: |
1da177e4 LT |
2988 | #if STATS |
2989 | { | |
2990 | int i = 0; | |
2991 | struct list_head *p; | |
2992 | ||
e498be7d CL |
2993 | p = l3->slabs_free.next; |
2994 | while (p != &(l3->slabs_free)) { | |
1da177e4 LT |
2995 | struct slab *slabp; |
2996 | ||
2997 | slabp = list_entry(p, struct slab, list); | |
2998 | BUG_ON(slabp->inuse); | |
2999 | ||
3000 | i++; | |
3001 | p = p->next; | |
3002 | } | |
3003 | STATS_SET_FREEABLE(cachep, i); | |
3004 | } | |
3005 | #endif | |
e498be7d | 3006 | spin_unlock(&l3->list_lock); |
1da177e4 | 3007 | ac->avail -= batchcount; |
a737b3e2 | 3008 | memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail); |
1da177e4 LT |
3009 | } |
3010 | ||
3011 | /* | |
a737b3e2 AM |
3012 | * Release an obj back to its cache. If the obj has a constructed state, it must |
3013 | * be in this state _before_ it is released. Called with disabled ints. | |
1da177e4 | 3014 | */ |
343e0d7a | 3015 | static inline void __cache_free(struct kmem_cache *cachep, void *objp) |
1da177e4 | 3016 | { |
9a2dba4b | 3017 | struct array_cache *ac = cpu_cache_get(cachep); |
1da177e4 LT |
3018 | |
3019 | check_irq_off(); | |
3020 | objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0)); | |
3021 | ||
e498be7d CL |
3022 | /* Make sure we are not freeing a object from another |
3023 | * node to the array cache on this cpu. | |
3024 | */ | |
3025 | #ifdef CONFIG_NUMA | |
3026 | { | |
3027 | struct slab *slabp; | |
6ed5eb22 | 3028 | slabp = virt_to_slab(objp); |
e498be7d CL |
3029 | if (unlikely(slabp->nodeid != numa_node_id())) { |
3030 | struct array_cache *alien = NULL; | |
3031 | int nodeid = slabp->nodeid; | |
a737b3e2 | 3032 | struct kmem_list3 *l3; |
e498be7d | 3033 | |
a737b3e2 | 3034 | l3 = cachep->nodelists[numa_node_id()]; |
e498be7d CL |
3035 | STATS_INC_NODEFREES(cachep); |
3036 | if (l3->alien && l3->alien[nodeid]) { | |
3037 | alien = l3->alien[nodeid]; | |
3038 | spin_lock(&alien->lock); | |
3039 | if (unlikely(alien->avail == alien->limit)) | |
3040 | __drain_alien_cache(cachep, | |
b28a02de | 3041 | alien, nodeid); |
e498be7d CL |
3042 | alien->entry[alien->avail++] = objp; |
3043 | spin_unlock(&alien->lock); | |
3044 | } else { | |
3045 | spin_lock(&(cachep->nodelists[nodeid])-> | |
b28a02de | 3046 | list_lock); |
ff69416e | 3047 | free_block(cachep, &objp, 1, nodeid); |
e498be7d | 3048 | spin_unlock(&(cachep->nodelists[nodeid])-> |
b28a02de | 3049 | list_lock); |
e498be7d CL |
3050 | } |
3051 | return; | |
3052 | } | |
3053 | } | |
3054 | #endif | |
1da177e4 LT |
3055 | if (likely(ac->avail < ac->limit)) { |
3056 | STATS_INC_FREEHIT(cachep); | |
e498be7d | 3057 | ac->entry[ac->avail++] = objp; |
1da177e4 LT |
3058 | return; |
3059 | } else { | |
3060 | STATS_INC_FREEMISS(cachep); | |
3061 | cache_flusharray(cachep, ac); | |
e498be7d | 3062 | ac->entry[ac->avail++] = objp; |
1da177e4 LT |
3063 | } |
3064 | } | |
3065 | ||
3066 | /** | |
3067 | * kmem_cache_alloc - Allocate an object | |
3068 | * @cachep: The cache to allocate from. | |
3069 | * @flags: See kmalloc(). | |
3070 | * | |
3071 | * Allocate an object from this cache. The flags are only relevant | |
3072 | * if the cache has no available objects. | |
3073 | */ | |
343e0d7a | 3074 | void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 | 3075 | { |
7fd6b141 | 3076 | return __cache_alloc(cachep, flags, __builtin_return_address(0)); |
1da177e4 LT |
3077 | } |
3078 | EXPORT_SYMBOL(kmem_cache_alloc); | |
3079 | ||
3080 | /** | |
3081 | * kmem_ptr_validate - check if an untrusted pointer might | |
3082 | * be a slab entry. | |
3083 | * @cachep: the cache we're checking against | |
3084 | * @ptr: pointer to validate | |
3085 | * | |
3086 | * This verifies that the untrusted pointer looks sane: | |
3087 | * it is _not_ a guarantee that the pointer is actually | |
3088 | * part of the slab cache in question, but it at least | |
3089 | * validates that the pointer can be dereferenced and | |
3090 | * looks half-way sane. | |
3091 | * | |
3092 | * Currently only used for dentry validation. | |
3093 | */ | |
343e0d7a | 3094 | int fastcall kmem_ptr_validate(struct kmem_cache *cachep, void *ptr) |
1da177e4 | 3095 | { |
b28a02de | 3096 | unsigned long addr = (unsigned long)ptr; |
1da177e4 | 3097 | unsigned long min_addr = PAGE_OFFSET; |
b28a02de | 3098 | unsigned long align_mask = BYTES_PER_WORD - 1; |
3dafccf2 | 3099 | unsigned long size = cachep->buffer_size; |
1da177e4 LT |
3100 | struct page *page; |
3101 | ||
3102 | if (unlikely(addr < min_addr)) | |
3103 | goto out; | |
3104 | if (unlikely(addr > (unsigned long)high_memory - size)) | |
3105 | goto out; | |
3106 | if (unlikely(addr & align_mask)) | |
3107 | goto out; | |
3108 | if (unlikely(!kern_addr_valid(addr))) | |
3109 | goto out; | |
3110 | if (unlikely(!kern_addr_valid(addr + size - 1))) | |
3111 | goto out; | |
3112 | page = virt_to_page(ptr); | |
3113 | if (unlikely(!PageSlab(page))) | |
3114 | goto out; | |
065d41cb | 3115 | if (unlikely(page_get_cache(page) != cachep)) |
1da177e4 LT |
3116 | goto out; |
3117 | return 1; | |
a737b3e2 | 3118 | out: |
1da177e4 LT |
3119 | return 0; |
3120 | } | |
3121 | ||
3122 | #ifdef CONFIG_NUMA | |
3123 | /** | |
3124 | * kmem_cache_alloc_node - Allocate an object on the specified node | |
3125 | * @cachep: The cache to allocate from. | |
3126 | * @flags: See kmalloc(). | |
3127 | * @nodeid: node number of the target node. | |
3128 | * | |
3129 | * Identical to kmem_cache_alloc, except that this function is slow | |
3130 | * and can sleep. And it will allocate memory on the given node, which | |
3131 | * can improve the performance for cpu bound structures. | |
e498be7d CL |
3132 | * New and improved: it will now make sure that the object gets |
3133 | * put on the correct node list so that there is no false sharing. | |
1da177e4 | 3134 | */ |
343e0d7a | 3135 | void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 | 3136 | { |
e498be7d CL |
3137 | unsigned long save_flags; |
3138 | void *ptr; | |
1da177e4 | 3139 | |
e498be7d CL |
3140 | cache_alloc_debugcheck_before(cachep, flags); |
3141 | local_irq_save(save_flags); | |
18f820f6 CL |
3142 | |
3143 | if (nodeid == -1 || nodeid == numa_node_id() || | |
a737b3e2 | 3144 | !cachep->nodelists[nodeid]) |
5c382300 AK |
3145 | ptr = ____cache_alloc(cachep, flags); |
3146 | else | |
3147 | ptr = __cache_alloc_node(cachep, flags, nodeid); | |
e498be7d | 3148 | local_irq_restore(save_flags); |
18f820f6 CL |
3149 | |
3150 | ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, | |
3151 | __builtin_return_address(0)); | |
1da177e4 | 3152 | |
e498be7d | 3153 | return ptr; |
1da177e4 LT |
3154 | } |
3155 | EXPORT_SYMBOL(kmem_cache_alloc_node); | |
3156 | ||
dd0fc66f | 3157 | void *kmalloc_node(size_t size, gfp_t flags, int node) |
97e2bde4 | 3158 | { |
343e0d7a | 3159 | struct kmem_cache *cachep; |
97e2bde4 MS |
3160 | |
3161 | cachep = kmem_find_general_cachep(size, flags); | |
3162 | if (unlikely(cachep == NULL)) | |
3163 | return NULL; | |
3164 | return kmem_cache_alloc_node(cachep, flags, node); | |
3165 | } | |
3166 | EXPORT_SYMBOL(kmalloc_node); | |
1da177e4 LT |
3167 | #endif |
3168 | ||
3169 | /** | |
3170 | * kmalloc - allocate memory | |
3171 | * @size: how many bytes of memory are required. | |
3172 | * @flags: the type of memory to allocate. | |
3173 | * | |
3174 | * kmalloc is the normal method of allocating memory | |
3175 | * in the kernel. | |
3176 | * | |
3177 | * The @flags argument may be one of: | |
3178 | * | |
3179 | * %GFP_USER - Allocate memory on behalf of user. May sleep. | |
3180 | * | |
3181 | * %GFP_KERNEL - Allocate normal kernel ram. May sleep. | |
3182 | * | |
3183 | * %GFP_ATOMIC - Allocation will not sleep. Use inside interrupt handlers. | |
3184 | * | |
3185 | * Additionally, the %GFP_DMA flag may be set to indicate the memory | |
3186 | * must be suitable for DMA. This can mean different things on different | |
3187 | * platforms. For example, on i386, it means that the memory must come | |
3188 | * from the first 16MB. | |
3189 | */ | |
7fd6b141 PE |
3190 | static __always_inline void *__do_kmalloc(size_t size, gfp_t flags, |
3191 | void *caller) | |
1da177e4 | 3192 | { |
343e0d7a | 3193 | struct kmem_cache *cachep; |
1da177e4 | 3194 | |
97e2bde4 MS |
3195 | /* If you want to save a few bytes .text space: replace |
3196 | * __ with kmem_. | |
3197 | * Then kmalloc uses the uninlined functions instead of the inline | |
3198 | * functions. | |
3199 | */ | |
3200 | cachep = __find_general_cachep(size, flags); | |
dbdb9045 AM |
3201 | if (unlikely(cachep == NULL)) |
3202 | return NULL; | |
7fd6b141 PE |
3203 | return __cache_alloc(cachep, flags, caller); |
3204 | } | |
3205 | ||
3206 | #ifndef CONFIG_DEBUG_SLAB | |
3207 | ||
3208 | void *__kmalloc(size_t size, gfp_t flags) | |
3209 | { | |
3210 | return __do_kmalloc(size, flags, NULL); | |
1da177e4 LT |
3211 | } |
3212 | EXPORT_SYMBOL(__kmalloc); | |
3213 | ||
7fd6b141 PE |
3214 | #else |
3215 | ||
3216 | void *__kmalloc_track_caller(size_t size, gfp_t flags, void *caller) | |
3217 | { | |
3218 | return __do_kmalloc(size, flags, caller); | |
3219 | } | |
3220 | EXPORT_SYMBOL(__kmalloc_track_caller); | |
3221 | ||
3222 | #endif | |
3223 | ||
1da177e4 LT |
3224 | #ifdef CONFIG_SMP |
3225 | /** | |
3226 | * __alloc_percpu - allocate one copy of the object for every present | |
3227 | * cpu in the system, zeroing them. | |
3228 | * Objects should be dereferenced using the per_cpu_ptr macro only. | |
3229 | * | |
3230 | * @size: how many bytes of memory are required. | |
1da177e4 | 3231 | */ |
f9f75005 | 3232 | void *__alloc_percpu(size_t size) |
1da177e4 LT |
3233 | { |
3234 | int i; | |
b28a02de | 3235 | struct percpu_data *pdata = kmalloc(sizeof(*pdata), GFP_KERNEL); |
1da177e4 LT |
3236 | |
3237 | if (!pdata) | |
3238 | return NULL; | |
3239 | ||
e498be7d CL |
3240 | /* |
3241 | * Cannot use for_each_online_cpu since a cpu may come online | |
3242 | * and we have no way of figuring out how to fix the array | |
3243 | * that we have allocated then.... | |
3244 | */ | |
3245 | for_each_cpu(i) { | |
3246 | int node = cpu_to_node(i); | |
3247 | ||
3248 | if (node_online(node)) | |
3249 | pdata->ptrs[i] = kmalloc_node(size, GFP_KERNEL, node); | |
3250 | else | |
3251 | pdata->ptrs[i] = kmalloc(size, GFP_KERNEL); | |
1da177e4 LT |
3252 | |
3253 | if (!pdata->ptrs[i]) | |
3254 | goto unwind_oom; | |
3255 | memset(pdata->ptrs[i], 0, size); | |
3256 | } | |
3257 | ||
3258 | /* Catch derefs w/o wrappers */ | |
b28a02de | 3259 | return (void *)(~(unsigned long)pdata); |
1da177e4 | 3260 | |
a737b3e2 | 3261 | unwind_oom: |
1da177e4 LT |
3262 | while (--i >= 0) { |
3263 | if (!cpu_possible(i)) | |
3264 | continue; | |
3265 | kfree(pdata->ptrs[i]); | |
3266 | } | |
3267 | kfree(pdata); | |
3268 | return NULL; | |
3269 | } | |
3270 | EXPORT_SYMBOL(__alloc_percpu); | |
3271 | #endif | |
3272 | ||
3273 | /** | |
3274 | * kmem_cache_free - Deallocate an object | |
3275 | * @cachep: The cache the allocation was from. | |
3276 | * @objp: The previously allocated object. | |
3277 | * | |
3278 | * Free an object which was previously allocated from this | |
3279 | * cache. | |
3280 | */ | |
343e0d7a | 3281 | void kmem_cache_free(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
3282 | { |
3283 | unsigned long flags; | |
3284 | ||
3285 | local_irq_save(flags); | |
3286 | __cache_free(cachep, objp); | |
3287 | local_irq_restore(flags); | |
3288 | } | |
3289 | EXPORT_SYMBOL(kmem_cache_free); | |
3290 | ||
1da177e4 LT |
3291 | /** |
3292 | * kfree - free previously allocated memory | |
3293 | * @objp: pointer returned by kmalloc. | |
3294 | * | |
80e93eff PE |
3295 | * If @objp is NULL, no operation is performed. |
3296 | * | |
1da177e4 LT |
3297 | * Don't free memory not originally allocated by kmalloc() |
3298 | * or you will run into trouble. | |
3299 | */ | |
3300 | void kfree(const void *objp) | |
3301 | { | |
343e0d7a | 3302 | struct kmem_cache *c; |
1da177e4 LT |
3303 | unsigned long flags; |
3304 | ||
3305 | if (unlikely(!objp)) | |
3306 | return; | |
3307 | local_irq_save(flags); | |
3308 | kfree_debugcheck(objp); | |
6ed5eb22 | 3309 | c = virt_to_cache(objp); |
3dafccf2 | 3310 | mutex_debug_check_no_locks_freed(objp, obj_size(c)); |
b28a02de | 3311 | __cache_free(c, (void *)objp); |
1da177e4 LT |
3312 | local_irq_restore(flags); |
3313 | } | |
3314 | EXPORT_SYMBOL(kfree); | |
3315 | ||
3316 | #ifdef CONFIG_SMP | |
3317 | /** | |
3318 | * free_percpu - free previously allocated percpu memory | |
3319 | * @objp: pointer returned by alloc_percpu. | |
3320 | * | |
3321 | * Don't free memory not originally allocated by alloc_percpu() | |
3322 | * The complemented objp is to check for that. | |
3323 | */ | |
b28a02de | 3324 | void free_percpu(const void *objp) |
1da177e4 LT |
3325 | { |
3326 | int i; | |
b28a02de | 3327 | struct percpu_data *p = (struct percpu_data *)(~(unsigned long)objp); |
1da177e4 | 3328 | |
e498be7d CL |
3329 | /* |
3330 | * We allocate for all cpus so we cannot use for online cpu here. | |
3331 | */ | |
3332 | for_each_cpu(i) | |
b28a02de | 3333 | kfree(p->ptrs[i]); |
1da177e4 LT |
3334 | kfree(p); |
3335 | } | |
3336 | EXPORT_SYMBOL(free_percpu); | |
3337 | #endif | |
3338 | ||
343e0d7a | 3339 | unsigned int kmem_cache_size(struct kmem_cache *cachep) |
1da177e4 | 3340 | { |
3dafccf2 | 3341 | return obj_size(cachep); |
1da177e4 LT |
3342 | } |
3343 | EXPORT_SYMBOL(kmem_cache_size); | |
3344 | ||
343e0d7a | 3345 | const char *kmem_cache_name(struct kmem_cache *cachep) |
1944972d ACM |
3346 | { |
3347 | return cachep->name; | |
3348 | } | |
3349 | EXPORT_SYMBOL_GPL(kmem_cache_name); | |
3350 | ||
e498be7d CL |
3351 | /* |
3352 | * This initializes kmem_list3 for all nodes. | |
3353 | */ | |
343e0d7a | 3354 | static int alloc_kmemlist(struct kmem_cache *cachep) |
e498be7d CL |
3355 | { |
3356 | int node; | |
3357 | struct kmem_list3 *l3; | |
3358 | int err = 0; | |
3359 | ||
3360 | for_each_online_node(node) { | |
3361 | struct array_cache *nc = NULL, *new; | |
3362 | struct array_cache **new_alien = NULL; | |
3363 | #ifdef CONFIG_NUMA | |
a737b3e2 AM |
3364 | new_alien = alloc_alien_cache(node, cachep->limit); |
3365 | if (!new_alien) | |
e498be7d CL |
3366 | goto fail; |
3367 | #endif | |
a737b3e2 AM |
3368 | new = alloc_arraycache(node, cachep->shared*cachep->batchcount, |
3369 | 0xbaadf00d); | |
3370 | if (!new) | |
e498be7d | 3371 | goto fail; |
a737b3e2 AM |
3372 | l3 = cachep->nodelists[node]; |
3373 | if (l3) { | |
e498be7d CL |
3374 | spin_lock_irq(&l3->list_lock); |
3375 | ||
a737b3e2 AM |
3376 | nc = cachep->nodelists[node]->shared; |
3377 | if (nc) | |
b28a02de | 3378 | free_block(cachep, nc->entry, nc->avail, node); |
e498be7d CL |
3379 | |
3380 | l3->shared = new; | |
3381 | if (!cachep->nodelists[node]->alien) { | |
3382 | l3->alien = new_alien; | |
3383 | new_alien = NULL; | |
3384 | } | |
b28a02de | 3385 | l3->free_limit = (1 + nr_cpus_node(node)) * |
a737b3e2 | 3386 | cachep->batchcount + cachep->num; |
e498be7d CL |
3387 | spin_unlock_irq(&l3->list_lock); |
3388 | kfree(nc); | |
3389 | free_alien_cache(new_alien); | |
3390 | continue; | |
3391 | } | |
a737b3e2 AM |
3392 | l3 = kmalloc_node(sizeof(struct kmem_list3), GFP_KERNEL, node); |
3393 | if (!l3) | |
e498be7d CL |
3394 | goto fail; |
3395 | ||
3396 | kmem_list3_init(l3); | |
3397 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + | |
a737b3e2 | 3398 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
e498be7d CL |
3399 | l3->shared = new; |
3400 | l3->alien = new_alien; | |
b28a02de | 3401 | l3->free_limit = (1 + nr_cpus_node(node)) * |
a737b3e2 | 3402 | cachep->batchcount + cachep->num; |
e498be7d CL |
3403 | cachep->nodelists[node] = l3; |
3404 | } | |
3405 | return err; | |
a737b3e2 | 3406 | fail: |
e498be7d CL |
3407 | err = -ENOMEM; |
3408 | return err; | |
3409 | } | |
3410 | ||
1da177e4 | 3411 | struct ccupdate_struct { |
343e0d7a | 3412 | struct kmem_cache *cachep; |
1da177e4 LT |
3413 | struct array_cache *new[NR_CPUS]; |
3414 | }; | |
3415 | ||
3416 | static void do_ccupdate_local(void *info) | |
3417 | { | |
a737b3e2 | 3418 | struct ccupdate_struct *new = info; |
1da177e4 LT |
3419 | struct array_cache *old; |
3420 | ||
3421 | check_irq_off(); | |
9a2dba4b | 3422 | old = cpu_cache_get(new->cachep); |
e498be7d | 3423 | |
1da177e4 LT |
3424 | new->cachep->array[smp_processor_id()] = new->new[smp_processor_id()]; |
3425 | new->new[smp_processor_id()] = old; | |
3426 | } | |
3427 | ||
b5d8ca7c | 3428 | /* Always called with the cache_chain_mutex held */ |
a737b3e2 AM |
3429 | static int do_tune_cpucache(struct kmem_cache *cachep, int limit, |
3430 | int batchcount, int shared) | |
1da177e4 LT |
3431 | { |
3432 | struct ccupdate_struct new; | |
e498be7d | 3433 | int i, err; |
1da177e4 | 3434 | |
b28a02de | 3435 | memset(&new.new, 0, sizeof(new.new)); |
e498be7d | 3436 | for_each_online_cpu(i) { |
a737b3e2 AM |
3437 | new.new[i] = alloc_arraycache(cpu_to_node(i), limit, |
3438 | batchcount); | |
e498be7d | 3439 | if (!new.new[i]) { |
b28a02de PE |
3440 | for (i--; i >= 0; i--) |
3441 | kfree(new.new[i]); | |
e498be7d | 3442 | return -ENOMEM; |
1da177e4 LT |
3443 | } |
3444 | } | |
3445 | new.cachep = cachep; | |
3446 | ||
3447 | smp_call_function_all_cpus(do_ccupdate_local, (void *)&new); | |
e498be7d | 3448 | |
1da177e4 | 3449 | check_irq_on(); |
1da177e4 LT |
3450 | cachep->batchcount = batchcount; |
3451 | cachep->limit = limit; | |
e498be7d | 3452 | cachep->shared = shared; |
1da177e4 | 3453 | |
e498be7d | 3454 | for_each_online_cpu(i) { |
1da177e4 LT |
3455 | struct array_cache *ccold = new.new[i]; |
3456 | if (!ccold) | |
3457 | continue; | |
e498be7d | 3458 | spin_lock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
ff69416e | 3459 | free_block(cachep, ccold->entry, ccold->avail, cpu_to_node(i)); |
e498be7d | 3460 | spin_unlock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
1da177e4 LT |
3461 | kfree(ccold); |
3462 | } | |
1da177e4 | 3463 | |
e498be7d CL |
3464 | err = alloc_kmemlist(cachep); |
3465 | if (err) { | |
3466 | printk(KERN_ERR "alloc_kmemlist failed for %s, error %d.\n", | |
b28a02de | 3467 | cachep->name, -err); |
e498be7d | 3468 | BUG(); |
1da177e4 | 3469 | } |
1da177e4 LT |
3470 | return 0; |
3471 | } | |
3472 | ||
b5d8ca7c | 3473 | /* Called with cache_chain_mutex held always */ |
343e0d7a | 3474 | static void enable_cpucache(struct kmem_cache *cachep) |
1da177e4 LT |
3475 | { |
3476 | int err; | |
3477 | int limit, shared; | |
3478 | ||
a737b3e2 AM |
3479 | /* |
3480 | * The head array serves three purposes: | |
1da177e4 LT |
3481 | * - create a LIFO ordering, i.e. return objects that are cache-warm |
3482 | * - reduce the number of spinlock operations. | |
a737b3e2 | 3483 | * - reduce the number of linked list operations on the slab and |
1da177e4 LT |
3484 | * bufctl chains: array operations are cheaper. |
3485 | * The numbers are guessed, we should auto-tune as described by | |
3486 | * Bonwick. | |
3487 | */ | |
3dafccf2 | 3488 | if (cachep->buffer_size > 131072) |
1da177e4 | 3489 | limit = 1; |
3dafccf2 | 3490 | else if (cachep->buffer_size > PAGE_SIZE) |
1da177e4 | 3491 | limit = 8; |
3dafccf2 | 3492 | else if (cachep->buffer_size > 1024) |
1da177e4 | 3493 | limit = 24; |
3dafccf2 | 3494 | else if (cachep->buffer_size > 256) |
1da177e4 LT |
3495 | limit = 54; |
3496 | else | |
3497 | limit = 120; | |
3498 | ||
a737b3e2 AM |
3499 | /* |
3500 | * CPU bound tasks (e.g. network routing) can exhibit cpu bound | |
1da177e4 LT |
3501 | * allocation behaviour: Most allocs on one cpu, most free operations |
3502 | * on another cpu. For these cases, an efficient object passing between | |
3503 | * cpus is necessary. This is provided by a shared array. The array | |
3504 | * replaces Bonwick's magazine layer. | |
3505 | * On uniprocessor, it's functionally equivalent (but less efficient) | |
3506 | * to a larger limit. Thus disabled by default. | |
3507 | */ | |
3508 | shared = 0; | |
3509 | #ifdef CONFIG_SMP | |
3dafccf2 | 3510 | if (cachep->buffer_size <= PAGE_SIZE) |
1da177e4 LT |
3511 | shared = 8; |
3512 | #endif | |
3513 | ||
3514 | #if DEBUG | |
a737b3e2 AM |
3515 | /* |
3516 | * With debugging enabled, large batchcount lead to excessively long | |
3517 | * periods with disabled local interrupts. Limit the batchcount | |
1da177e4 LT |
3518 | */ |
3519 | if (limit > 32) | |
3520 | limit = 32; | |
3521 | #endif | |
b28a02de | 3522 | err = do_tune_cpucache(cachep, limit, (limit + 1) / 2, shared); |
1da177e4 LT |
3523 | if (err) |
3524 | printk(KERN_ERR "enable_cpucache failed for %s, error %d.\n", | |
b28a02de | 3525 | cachep->name, -err); |
1da177e4 LT |
3526 | } |
3527 | ||
a737b3e2 AM |
3528 | static void drain_array_locked(struct kmem_cache *cachep, |
3529 | struct array_cache *ac, int force, int node) | |
1da177e4 LT |
3530 | { |
3531 | int tofree; | |
3532 | ||
e498be7d | 3533 | check_spinlock_acquired_node(cachep, node); |
1da177e4 LT |
3534 | if (ac->touched && !force) { |
3535 | ac->touched = 0; | |
3536 | } else if (ac->avail) { | |
b28a02de | 3537 | tofree = force ? ac->avail : (ac->limit + 4) / 5; |
a737b3e2 | 3538 | if (tofree > ac->avail) |
b28a02de | 3539 | tofree = (ac->avail + 1) / 2; |
ff69416e | 3540 | free_block(cachep, ac->entry, tofree, node); |
1da177e4 | 3541 | ac->avail -= tofree; |
e498be7d | 3542 | memmove(ac->entry, &(ac->entry[tofree]), |
b28a02de | 3543 | sizeof(void *) * ac->avail); |
1da177e4 LT |
3544 | } |
3545 | } | |
3546 | ||
3547 | /** | |
3548 | * cache_reap - Reclaim memory from caches. | |
1e5d5331 | 3549 | * @unused: unused parameter |
1da177e4 LT |
3550 | * |
3551 | * Called from workqueue/eventd every few seconds. | |
3552 | * Purpose: | |
3553 | * - clear the per-cpu caches for this CPU. | |
3554 | * - return freeable pages to the main free memory pool. | |
3555 | * | |
a737b3e2 AM |
3556 | * If we cannot acquire the cache chain mutex then just give up - we'll try |
3557 | * again on the next iteration. | |
1da177e4 LT |
3558 | */ |
3559 | static void cache_reap(void *unused) | |
3560 | { | |
3561 | struct list_head *walk; | |
e498be7d | 3562 | struct kmem_list3 *l3; |
1da177e4 | 3563 | |
fc0abb14 | 3564 | if (!mutex_trylock(&cache_chain_mutex)) { |
1da177e4 | 3565 | /* Give up. Setup the next iteration. */ |
b28a02de PE |
3566 | schedule_delayed_work(&__get_cpu_var(reap_work), |
3567 | REAPTIMEOUT_CPUC); | |
1da177e4 LT |
3568 | return; |
3569 | } | |
3570 | ||
3571 | list_for_each(walk, &cache_chain) { | |
343e0d7a | 3572 | struct kmem_cache *searchp; |
b28a02de | 3573 | struct list_head *p; |
1da177e4 LT |
3574 | int tofree; |
3575 | struct slab *slabp; | |
3576 | ||
343e0d7a | 3577 | searchp = list_entry(walk, struct kmem_cache, next); |
1da177e4 LT |
3578 | |
3579 | if (searchp->flags & SLAB_NO_REAP) | |
3580 | goto next; | |
3581 | ||
3582 | check_irq_on(); | |
3583 | ||
e498be7d | 3584 | l3 = searchp->nodelists[numa_node_id()]; |
8fce4d8e | 3585 | reap_alien(searchp, l3); |
e498be7d | 3586 | spin_lock_irq(&l3->list_lock); |
1da177e4 | 3587 | |
9a2dba4b | 3588 | drain_array_locked(searchp, cpu_cache_get(searchp), 0, |
b28a02de | 3589 | numa_node_id()); |
1da177e4 | 3590 | |
e498be7d | 3591 | if (time_after(l3->next_reap, jiffies)) |
1da177e4 LT |
3592 | goto next_unlock; |
3593 | ||
e498be7d | 3594 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3; |
1da177e4 | 3595 | |
e498be7d CL |
3596 | if (l3->shared) |
3597 | drain_array_locked(searchp, l3->shared, 0, | |
b28a02de | 3598 | numa_node_id()); |
1da177e4 | 3599 | |
e498be7d CL |
3600 | if (l3->free_touched) { |
3601 | l3->free_touched = 0; | |
1da177e4 LT |
3602 | goto next_unlock; |
3603 | } | |
3604 | ||
a737b3e2 AM |
3605 | tofree = (l3->free_limit + 5 * searchp->num - 1) / |
3606 | (5 * searchp->num); | |
1da177e4 | 3607 | do { |
e498be7d CL |
3608 | p = l3->slabs_free.next; |
3609 | if (p == &(l3->slabs_free)) | |
1da177e4 LT |
3610 | break; |
3611 | ||
3612 | slabp = list_entry(p, struct slab, list); | |
3613 | BUG_ON(slabp->inuse); | |
3614 | list_del(&slabp->list); | |
3615 | STATS_INC_REAPED(searchp); | |
3616 | ||
a737b3e2 AM |
3617 | /* |
3618 | * Safe to drop the lock. The slab is no longer linked | |
3619 | * to the cache. searchp cannot disappear, we hold | |
1da177e4 LT |
3620 | * cache_chain_lock |
3621 | */ | |
e498be7d CL |
3622 | l3->free_objects -= searchp->num; |
3623 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 3624 | slab_destroy(searchp, slabp); |
e498be7d | 3625 | spin_lock_irq(&l3->list_lock); |
b28a02de | 3626 | } while (--tofree > 0); |
a737b3e2 | 3627 | next_unlock: |
e498be7d | 3628 | spin_unlock_irq(&l3->list_lock); |
a737b3e2 | 3629 | next: |
1da177e4 LT |
3630 | cond_resched(); |
3631 | } | |
3632 | check_irq_on(); | |
fc0abb14 | 3633 | mutex_unlock(&cache_chain_mutex); |
8fce4d8e | 3634 | next_reap_node(); |
a737b3e2 | 3635 | /* Set up the next iteration */ |
cd61ef62 | 3636 | schedule_delayed_work(&__get_cpu_var(reap_work), REAPTIMEOUT_CPUC); |
1da177e4 LT |
3637 | } |
3638 | ||
3639 | #ifdef CONFIG_PROC_FS | |
3640 | ||
85289f98 | 3641 | static void print_slabinfo_header(struct seq_file *m) |
1da177e4 | 3642 | { |
85289f98 PE |
3643 | /* |
3644 | * Output format version, so at least we can change it | |
3645 | * without _too_ many complaints. | |
3646 | */ | |
1da177e4 | 3647 | #if STATS |
85289f98 | 3648 | seq_puts(m, "slabinfo - version: 2.1 (statistics)\n"); |
1da177e4 | 3649 | #else |
85289f98 | 3650 | seq_puts(m, "slabinfo - version: 2.1\n"); |
1da177e4 | 3651 | #endif |
85289f98 PE |
3652 | seq_puts(m, "# name <active_objs> <num_objs> <objsize> " |
3653 | "<objperslab> <pagesperslab>"); | |
3654 | seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); | |
3655 | seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); | |
1da177e4 | 3656 | #if STATS |
85289f98 PE |
3657 | seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> " |
3658 | "<error> <maxfreeable> <nodeallocs> <remotefrees>"); | |
3659 | seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>"); | |
1da177e4 | 3660 | #endif |
85289f98 PE |
3661 | seq_putc(m, '\n'); |
3662 | } | |
3663 | ||
3664 | static void *s_start(struct seq_file *m, loff_t *pos) | |
3665 | { | |
3666 | loff_t n = *pos; | |
3667 | struct list_head *p; | |
3668 | ||
fc0abb14 | 3669 | mutex_lock(&cache_chain_mutex); |
85289f98 PE |
3670 | if (!n) |
3671 | print_slabinfo_header(m); | |
1da177e4 LT |
3672 | p = cache_chain.next; |
3673 | while (n--) { | |
3674 | p = p->next; | |
3675 | if (p == &cache_chain) | |
3676 | return NULL; | |
3677 | } | |
343e0d7a | 3678 | return list_entry(p, struct kmem_cache, next); |
1da177e4 LT |
3679 | } |
3680 | ||
3681 | static void *s_next(struct seq_file *m, void *p, loff_t *pos) | |
3682 | { | |
343e0d7a | 3683 | struct kmem_cache *cachep = p; |
1da177e4 | 3684 | ++*pos; |
a737b3e2 AM |
3685 | return cachep->next.next == &cache_chain ? |
3686 | NULL : list_entry(cachep->next.next, struct kmem_cache, next); | |
1da177e4 LT |
3687 | } |
3688 | ||
3689 | static void s_stop(struct seq_file *m, void *p) | |
3690 | { | |
fc0abb14 | 3691 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
3692 | } |
3693 | ||
3694 | static int s_show(struct seq_file *m, void *p) | |
3695 | { | |
343e0d7a | 3696 | struct kmem_cache *cachep = p; |
1da177e4 | 3697 | struct list_head *q; |
b28a02de PE |
3698 | struct slab *slabp; |
3699 | unsigned long active_objs; | |
3700 | unsigned long num_objs; | |
3701 | unsigned long active_slabs = 0; | |
3702 | unsigned long num_slabs, free_objects = 0, shared_avail = 0; | |
e498be7d | 3703 | const char *name; |
1da177e4 | 3704 | char *error = NULL; |
e498be7d CL |
3705 | int node; |
3706 | struct kmem_list3 *l3; | |
1da177e4 | 3707 | |
1da177e4 LT |
3708 | active_objs = 0; |
3709 | num_slabs = 0; | |
e498be7d CL |
3710 | for_each_online_node(node) { |
3711 | l3 = cachep->nodelists[node]; | |
3712 | if (!l3) | |
3713 | continue; | |
3714 | ||
ca3b9b91 RT |
3715 | check_irq_on(); |
3716 | spin_lock_irq(&l3->list_lock); | |
e498be7d | 3717 | |
b28a02de | 3718 | list_for_each(q, &l3->slabs_full) { |
e498be7d CL |
3719 | slabp = list_entry(q, struct slab, list); |
3720 | if (slabp->inuse != cachep->num && !error) | |
3721 | error = "slabs_full accounting error"; | |
3722 | active_objs += cachep->num; | |
3723 | active_slabs++; | |
3724 | } | |
b28a02de | 3725 | list_for_each(q, &l3->slabs_partial) { |
e498be7d CL |
3726 | slabp = list_entry(q, struct slab, list); |
3727 | if (slabp->inuse == cachep->num && !error) | |
3728 | error = "slabs_partial inuse accounting error"; | |
3729 | if (!slabp->inuse && !error) | |
3730 | error = "slabs_partial/inuse accounting error"; | |
3731 | active_objs += slabp->inuse; | |
3732 | active_slabs++; | |
3733 | } | |
b28a02de | 3734 | list_for_each(q, &l3->slabs_free) { |
e498be7d CL |
3735 | slabp = list_entry(q, struct slab, list); |
3736 | if (slabp->inuse && !error) | |
3737 | error = "slabs_free/inuse accounting error"; | |
3738 | num_slabs++; | |
3739 | } | |
3740 | free_objects += l3->free_objects; | |
4484ebf1 RT |
3741 | if (l3->shared) |
3742 | shared_avail += l3->shared->avail; | |
e498be7d | 3743 | |
ca3b9b91 | 3744 | spin_unlock_irq(&l3->list_lock); |
1da177e4 | 3745 | } |
b28a02de PE |
3746 | num_slabs += active_slabs; |
3747 | num_objs = num_slabs * cachep->num; | |
e498be7d | 3748 | if (num_objs - active_objs != free_objects && !error) |
1da177e4 LT |
3749 | error = "free_objects accounting error"; |
3750 | ||
b28a02de | 3751 | name = cachep->name; |
1da177e4 LT |
3752 | if (error) |
3753 | printk(KERN_ERR "slab: cache %s error: %s\n", name, error); | |
3754 | ||
3755 | seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", | |
3dafccf2 | 3756 | name, active_objs, num_objs, cachep->buffer_size, |
b28a02de | 3757 | cachep->num, (1 << cachep->gfporder)); |
1da177e4 | 3758 | seq_printf(m, " : tunables %4u %4u %4u", |
b28a02de | 3759 | cachep->limit, cachep->batchcount, cachep->shared); |
e498be7d | 3760 | seq_printf(m, " : slabdata %6lu %6lu %6lu", |
b28a02de | 3761 | active_slabs, num_slabs, shared_avail); |
1da177e4 | 3762 | #if STATS |
b28a02de | 3763 | { /* list3 stats */ |
1da177e4 LT |
3764 | unsigned long high = cachep->high_mark; |
3765 | unsigned long allocs = cachep->num_allocations; | |
3766 | unsigned long grown = cachep->grown; | |
3767 | unsigned long reaped = cachep->reaped; | |
3768 | unsigned long errors = cachep->errors; | |
3769 | unsigned long max_freeable = cachep->max_freeable; | |
1da177e4 | 3770 | unsigned long node_allocs = cachep->node_allocs; |
e498be7d | 3771 | unsigned long node_frees = cachep->node_frees; |
1da177e4 | 3772 | |
e498be7d | 3773 | seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu \ |
a737b3e2 AM |
3774 | %4lu %4lu %4lu %4lu", allocs, high, grown, |
3775 | reaped, errors, max_freeable, node_allocs, | |
3776 | node_frees); | |
1da177e4 LT |
3777 | } |
3778 | /* cpu stats */ | |
3779 | { | |
3780 | unsigned long allochit = atomic_read(&cachep->allochit); | |
3781 | unsigned long allocmiss = atomic_read(&cachep->allocmiss); | |
3782 | unsigned long freehit = atomic_read(&cachep->freehit); | |
3783 | unsigned long freemiss = atomic_read(&cachep->freemiss); | |
3784 | ||
3785 | seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", | |
b28a02de | 3786 | allochit, allocmiss, freehit, freemiss); |
1da177e4 LT |
3787 | } |
3788 | #endif | |
3789 | seq_putc(m, '\n'); | |
1da177e4 LT |
3790 | return 0; |
3791 | } | |
3792 | ||
3793 | /* | |
3794 | * slabinfo_op - iterator that generates /proc/slabinfo | |
3795 | * | |
3796 | * Output layout: | |
3797 | * cache-name | |
3798 | * num-active-objs | |
3799 | * total-objs | |
3800 | * object size | |
3801 | * num-active-slabs | |
3802 | * total-slabs | |
3803 | * num-pages-per-slab | |
3804 | * + further values on SMP and with statistics enabled | |
3805 | */ | |
3806 | ||
3807 | struct seq_operations slabinfo_op = { | |
b28a02de PE |
3808 | .start = s_start, |
3809 | .next = s_next, | |
3810 | .stop = s_stop, | |
3811 | .show = s_show, | |
1da177e4 LT |
3812 | }; |
3813 | ||
3814 | #define MAX_SLABINFO_WRITE 128 | |
3815 | /** | |
3816 | * slabinfo_write - Tuning for the slab allocator | |
3817 | * @file: unused | |
3818 | * @buffer: user buffer | |
3819 | * @count: data length | |
3820 | * @ppos: unused | |
3821 | */ | |
b28a02de PE |
3822 | ssize_t slabinfo_write(struct file *file, const char __user * buffer, |
3823 | size_t count, loff_t *ppos) | |
1da177e4 | 3824 | { |
b28a02de | 3825 | char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; |
1da177e4 LT |
3826 | int limit, batchcount, shared, res; |
3827 | struct list_head *p; | |
b28a02de | 3828 | |
1da177e4 LT |
3829 | if (count > MAX_SLABINFO_WRITE) |
3830 | return -EINVAL; | |
3831 | if (copy_from_user(&kbuf, buffer, count)) | |
3832 | return -EFAULT; | |
b28a02de | 3833 | kbuf[MAX_SLABINFO_WRITE] = '\0'; |
1da177e4 LT |
3834 | |
3835 | tmp = strchr(kbuf, ' '); | |
3836 | if (!tmp) | |
3837 | return -EINVAL; | |
3838 | *tmp = '\0'; | |
3839 | tmp++; | |
3840 | if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) | |
3841 | return -EINVAL; | |
3842 | ||
3843 | /* Find the cache in the chain of caches. */ | |
fc0abb14 | 3844 | mutex_lock(&cache_chain_mutex); |
1da177e4 | 3845 | res = -EINVAL; |
b28a02de | 3846 | list_for_each(p, &cache_chain) { |
a737b3e2 | 3847 | struct kmem_cache *cachep; |
1da177e4 | 3848 | |
a737b3e2 | 3849 | cachep = list_entry(p, struct kmem_cache, next); |
1da177e4 | 3850 | if (!strcmp(cachep->name, kbuf)) { |
a737b3e2 AM |
3851 | if (limit < 1 || batchcount < 1 || |
3852 | batchcount > limit || shared < 0) { | |
e498be7d | 3853 | res = 0; |
1da177e4 | 3854 | } else { |
e498be7d | 3855 | res = do_tune_cpucache(cachep, limit, |
b28a02de | 3856 | batchcount, shared); |
1da177e4 LT |
3857 | } |
3858 | break; | |
3859 | } | |
3860 | } | |
fc0abb14 | 3861 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
3862 | if (res >= 0) |
3863 | res = count; | |
3864 | return res; | |
3865 | } | |
3866 | #endif | |
3867 | ||
00e145b6 MS |
3868 | /** |
3869 | * ksize - get the actual amount of memory allocated for a given object | |
3870 | * @objp: Pointer to the object | |
3871 | * | |
3872 | * kmalloc may internally round up allocations and return more memory | |
3873 | * than requested. ksize() can be used to determine the actual amount of | |
3874 | * memory allocated. The caller may use this additional memory, even though | |
3875 | * a smaller amount of memory was initially specified with the kmalloc call. | |
3876 | * The caller must guarantee that objp points to a valid object previously | |
3877 | * allocated with either kmalloc() or kmem_cache_alloc(). The object | |
3878 | * must not be freed during the duration of the call. | |
3879 | */ | |
1da177e4 LT |
3880 | unsigned int ksize(const void *objp) |
3881 | { | |
00e145b6 MS |
3882 | if (unlikely(objp == NULL)) |
3883 | return 0; | |
1da177e4 | 3884 | |
6ed5eb22 | 3885 | return obj_size(virt_to_cache(objp)); |
1da177e4 | 3886 | } |