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