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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 | * | |
53 | * The c_cpuarray may not be read with enabled local interrupts - | |
54 | * it's changed with a smp_call_function(). | |
55 | * | |
56 | * SMP synchronization: | |
57 | * constructors and destructors are called without any locking. | |
343e0d7a | 58 | * Several members in struct kmem_cache and struct slab never change, they |
1da177e4 LT |
59 | * are accessed without any locking. |
60 | * The per-cpu arrays are never accessed from the wrong cpu, no locking, | |
61 | * and local interrupts are disabled so slab code is preempt-safe. | |
62 | * The non-constant members are protected with a per-cache irq spinlock. | |
63 | * | |
64 | * Many thanks to Mark Hemment, who wrote another per-cpu slab patch | |
65 | * in 2000 - many ideas in the current implementation are derived from | |
66 | * his patch. | |
67 | * | |
68 | * Further notes from the original documentation: | |
69 | * | |
70 | * 11 April '97. Started multi-threading - markhe | |
fc0abb14 | 71 | * The global cache-chain is protected by the mutex 'cache_chain_mutex'. |
1da177e4 LT |
72 | * The sem is only needed when accessing/extending the cache-chain, which |
73 | * can never happen inside an interrupt (kmem_cache_create(), | |
74 | * kmem_cache_shrink() and kmem_cache_reap()). | |
75 | * | |
76 | * At present, each engine can be growing a cache. This should be blocked. | |
77 | * | |
e498be7d CL |
78 | * 15 March 2005. NUMA slab allocator. |
79 | * Shai Fultheim <shai@scalex86.org>. | |
80 | * Shobhit Dayal <shobhit@calsoftinc.com> | |
81 | * Alok N Kataria <alokk@calsoftinc.com> | |
82 | * Christoph Lameter <christoph@lameter.com> | |
83 | * | |
84 | * Modified the slab allocator to be node aware on NUMA systems. | |
85 | * Each node has its own list of partial, free and full slabs. | |
86 | * All object allocations for a node occur from node specific slab lists. | |
1da177e4 LT |
87 | */ |
88 | ||
89 | #include <linux/config.h> | |
90 | #include <linux/slab.h> | |
91 | #include <linux/mm.h> | |
92 | #include <linux/swap.h> | |
93 | #include <linux/cache.h> | |
94 | #include <linux/interrupt.h> | |
95 | #include <linux/init.h> | |
96 | #include <linux/compiler.h> | |
97 | #include <linux/seq_file.h> | |
98 | #include <linux/notifier.h> | |
99 | #include <linux/kallsyms.h> | |
100 | #include <linux/cpu.h> | |
101 | #include <linux/sysctl.h> | |
102 | #include <linux/module.h> | |
103 | #include <linux/rcupdate.h> | |
543537bd | 104 | #include <linux/string.h> |
e498be7d | 105 | #include <linux/nodemask.h> |
dc85da15 | 106 | #include <linux/mempolicy.h> |
fc0abb14 | 107 | #include <linux/mutex.h> |
1da177e4 LT |
108 | |
109 | #include <asm/uaccess.h> | |
110 | #include <asm/cacheflush.h> | |
111 | #include <asm/tlbflush.h> | |
112 | #include <asm/page.h> | |
113 | ||
114 | /* | |
115 | * DEBUG - 1 for kmem_cache_create() to honour; SLAB_DEBUG_INITIAL, | |
116 | * SLAB_RED_ZONE & SLAB_POISON. | |
117 | * 0 for faster, smaller code (especially in the critical paths). | |
118 | * | |
119 | * STATS - 1 to collect stats for /proc/slabinfo. | |
120 | * 0 for faster, smaller code (especially in the critical paths). | |
121 | * | |
122 | * FORCED_DEBUG - 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible) | |
123 | */ | |
124 | ||
125 | #ifdef CONFIG_DEBUG_SLAB | |
126 | #define DEBUG 1 | |
127 | #define STATS 1 | |
128 | #define FORCED_DEBUG 1 | |
129 | #else | |
130 | #define DEBUG 0 | |
131 | #define STATS 0 | |
132 | #define FORCED_DEBUG 0 | |
133 | #endif | |
134 | ||
1da177e4 LT |
135 | /* Shouldn't this be in a header file somewhere? */ |
136 | #define BYTES_PER_WORD sizeof(void *) | |
137 | ||
138 | #ifndef cache_line_size | |
139 | #define cache_line_size() L1_CACHE_BYTES | |
140 | #endif | |
141 | ||
142 | #ifndef ARCH_KMALLOC_MINALIGN | |
143 | /* | |
144 | * Enforce a minimum alignment for the kmalloc caches. | |
145 | * Usually, the kmalloc caches are cache_line_size() aligned, except when | |
146 | * DEBUG and FORCED_DEBUG are enabled, then they are BYTES_PER_WORD aligned. | |
147 | * Some archs want to perform DMA into kmalloc caches and need a guaranteed | |
148 | * alignment larger than BYTES_PER_WORD. ARCH_KMALLOC_MINALIGN allows that. | |
149 | * Note that this flag disables some debug features. | |
150 | */ | |
151 | #define ARCH_KMALLOC_MINALIGN 0 | |
152 | #endif | |
153 | ||
154 | #ifndef ARCH_SLAB_MINALIGN | |
155 | /* | |
156 | * Enforce a minimum alignment for all caches. | |
157 | * Intended for archs that get misalignment faults even for BYTES_PER_WORD | |
158 | * aligned buffers. Includes ARCH_KMALLOC_MINALIGN. | |
159 | * If possible: Do not enable this flag for CONFIG_DEBUG_SLAB, it disables | |
160 | * some debug features. | |
161 | */ | |
162 | #define ARCH_SLAB_MINALIGN 0 | |
163 | #endif | |
164 | ||
165 | #ifndef ARCH_KMALLOC_FLAGS | |
166 | #define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN | |
167 | #endif | |
168 | ||
169 | /* Legal flag mask for kmem_cache_create(). */ | |
170 | #if DEBUG | |
171 | # define CREATE_MASK (SLAB_DEBUG_INITIAL | SLAB_RED_ZONE | \ | |
172 | SLAB_POISON | SLAB_HWCACHE_ALIGN | \ | |
173 | SLAB_NO_REAP | SLAB_CACHE_DMA | \ | |
174 | SLAB_MUST_HWCACHE_ALIGN | SLAB_STORE_USER | \ | |
175 | SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \ | |
176 | SLAB_DESTROY_BY_RCU) | |
177 | #else | |
178 | # define CREATE_MASK (SLAB_HWCACHE_ALIGN | SLAB_NO_REAP | \ | |
179 | SLAB_CACHE_DMA | SLAB_MUST_HWCACHE_ALIGN | \ | |
180 | SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \ | |
181 | SLAB_DESTROY_BY_RCU) | |
182 | #endif | |
183 | ||
184 | /* | |
185 | * kmem_bufctl_t: | |
186 | * | |
187 | * Bufctl's are used for linking objs within a slab | |
188 | * linked offsets. | |
189 | * | |
190 | * This implementation relies on "struct page" for locating the cache & | |
191 | * slab an object belongs to. | |
192 | * This allows the bufctl structure to be small (one int), but limits | |
193 | * the number of objects a slab (not a cache) can contain when off-slab | |
194 | * bufctls are used. The limit is the size of the largest general cache | |
195 | * that does not use off-slab slabs. | |
196 | * For 32bit archs with 4 kB pages, is this 56. | |
197 | * This is not serious, as it is only for large objects, when it is unwise | |
198 | * to have too many per slab. | |
199 | * Note: This limit can be raised by introducing a general cache whose size | |
200 | * is less than 512 (PAGE_SIZE<<3), but greater than 256. | |
201 | */ | |
202 | ||
fa5b08d5 | 203 | typedef unsigned int kmem_bufctl_t; |
1da177e4 LT |
204 | #define BUFCTL_END (((kmem_bufctl_t)(~0U))-0) |
205 | #define BUFCTL_FREE (((kmem_bufctl_t)(~0U))-1) | |
206 | #define SLAB_LIMIT (((kmem_bufctl_t)(~0U))-2) | |
207 | ||
208 | /* Max number of objs-per-slab for caches which use off-slab slabs. | |
209 | * Needed to avoid a possible looping condition in cache_grow(). | |
210 | */ | |
211 | static unsigned long offslab_limit; | |
212 | ||
213 | /* | |
214 | * struct slab | |
215 | * | |
216 | * Manages the objs in a slab. Placed either at the beginning of mem allocated | |
217 | * for a slab, or allocated from an general cache. | |
218 | * Slabs are chained into three list: fully used, partial, fully free slabs. | |
219 | */ | |
220 | struct slab { | |
b28a02de PE |
221 | struct list_head list; |
222 | unsigned long colouroff; | |
223 | void *s_mem; /* including colour offset */ | |
224 | unsigned int inuse; /* num of objs active in slab */ | |
225 | kmem_bufctl_t free; | |
226 | unsigned short nodeid; | |
1da177e4 LT |
227 | }; |
228 | ||
229 | /* | |
230 | * struct slab_rcu | |
231 | * | |
232 | * slab_destroy on a SLAB_DESTROY_BY_RCU cache uses this structure to | |
233 | * arrange for kmem_freepages to be called via RCU. This is useful if | |
234 | * we need to approach a kernel structure obliquely, from its address | |
235 | * obtained without the usual locking. We can lock the structure to | |
236 | * stabilize it and check it's still at the given address, only if we | |
237 | * can be sure that the memory has not been meanwhile reused for some | |
238 | * other kind of object (which our subsystem's lock might corrupt). | |
239 | * | |
240 | * rcu_read_lock before reading the address, then rcu_read_unlock after | |
241 | * taking the spinlock within the structure expected at that address. | |
242 | * | |
243 | * We assume struct slab_rcu can overlay struct slab when destroying. | |
244 | */ | |
245 | struct slab_rcu { | |
b28a02de | 246 | struct rcu_head head; |
343e0d7a | 247 | struct kmem_cache *cachep; |
b28a02de | 248 | void *addr; |
1da177e4 LT |
249 | }; |
250 | ||
251 | /* | |
252 | * struct array_cache | |
253 | * | |
1da177e4 LT |
254 | * Purpose: |
255 | * - LIFO ordering, to hand out cache-warm objects from _alloc | |
256 | * - reduce the number of linked list operations | |
257 | * - reduce spinlock operations | |
258 | * | |
259 | * The limit is stored in the per-cpu structure to reduce the data cache | |
260 | * footprint. | |
261 | * | |
262 | */ | |
263 | struct array_cache { | |
264 | unsigned int avail; | |
265 | unsigned int limit; | |
266 | unsigned int batchcount; | |
267 | unsigned int touched; | |
e498be7d CL |
268 | spinlock_t lock; |
269 | void *entry[0]; /* | |
270 | * Must have this definition in here for the proper | |
271 | * alignment of array_cache. Also simplifies accessing | |
272 | * the entries. | |
273 | * [0] is for gcc 2.95. It should really be []. | |
274 | */ | |
1da177e4 LT |
275 | }; |
276 | ||
277 | /* bootstrap: The caches do not work without cpuarrays anymore, | |
278 | * but the cpuarrays are allocated from the generic caches... | |
279 | */ | |
280 | #define BOOT_CPUCACHE_ENTRIES 1 | |
281 | struct arraycache_init { | |
282 | struct array_cache cache; | |
b28a02de | 283 | void *entries[BOOT_CPUCACHE_ENTRIES]; |
1da177e4 LT |
284 | }; |
285 | ||
286 | /* | |
e498be7d | 287 | * The slab lists for all objects. |
1da177e4 LT |
288 | */ |
289 | struct kmem_list3 { | |
b28a02de PE |
290 | struct list_head slabs_partial; /* partial list first, better asm code */ |
291 | struct list_head slabs_full; | |
292 | struct list_head slabs_free; | |
293 | unsigned long free_objects; | |
294 | unsigned long next_reap; | |
295 | int free_touched; | |
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 */ | |
1da177e4 LT |
301 | }; |
302 | ||
e498be7d CL |
303 | /* |
304 | * Need this for bootstrapping a per node allocator. | |
305 | */ | |
306 | #define NUM_INIT_LISTS (2 * MAX_NUMNODES + 1) | |
307 | struct kmem_list3 __initdata initkmem_list3[NUM_INIT_LISTS]; | |
308 | #define CACHE_CACHE 0 | |
309 | #define SIZE_AC 1 | |
310 | #define SIZE_L3 (1 + MAX_NUMNODES) | |
311 | ||
312 | /* | |
7243cc05 | 313 | * This function must be completely optimized away if |
e498be7d CL |
314 | * a constant is passed to it. Mostly the same as |
315 | * what is in linux/slab.h except it returns an | |
316 | * index. | |
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 | ||
354 | #define MAKE_LIST(cachep, listp, slab, nodeid) \ | |
355 | do { \ | |
356 | INIT_LIST_HEAD(listp); \ | |
357 | list_splice(&(cachep->nodelists[nodeid]->slab), listp); \ | |
358 | } while (0) | |
359 | ||
360 | #define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ | |
361 | do { \ | |
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 PE |
375 | struct array_cache *array[NR_CPUS]; |
376 | unsigned int batchcount; | |
377 | unsigned int limit; | |
378 | unsigned int shared; | |
3dafccf2 | 379 | unsigned int buffer_size; |
e498be7d | 380 | /* 2) touched by every alloc & free from the backend */ |
b28a02de PE |
381 | struct kmem_list3 *nodelists[MAX_NUMNODES]; |
382 | unsigned int flags; /* constant flags */ | |
383 | unsigned int num; /* # of objs per slab */ | |
384 | spinlock_t spinlock; | |
1da177e4 LT |
385 | |
386 | /* 3) cache_grow/shrink */ | |
387 | /* order of pgs per slab (2^n) */ | |
b28a02de | 388 | unsigned int gfporder; |
1da177e4 LT |
389 | |
390 | /* force GFP flags, e.g. GFP_DMA */ | |
b28a02de | 391 | gfp_t gfpflags; |
1da177e4 | 392 | |
b28a02de PE |
393 | size_t colour; /* cache colouring range */ |
394 | unsigned int colour_off; /* colour offset */ | |
343e0d7a | 395 | struct kmem_cache *slabp_cache; |
b28a02de PE |
396 | unsigned int slab_size; |
397 | unsigned int dflags; /* dynamic flags */ | |
1da177e4 LT |
398 | |
399 | /* constructor func */ | |
343e0d7a | 400 | void (*ctor) (void *, struct kmem_cache *, unsigned long); |
1da177e4 LT |
401 | |
402 | /* de-constructor func */ | |
343e0d7a | 403 | void (*dtor) (void *, struct kmem_cache *, unsigned long); |
1da177e4 LT |
404 | |
405 | /* 4) cache creation/removal */ | |
b28a02de PE |
406 | const char *name; |
407 | struct list_head next; | |
1da177e4 LT |
408 | |
409 | /* 5) statistics */ | |
410 | #if STATS | |
b28a02de PE |
411 | unsigned long num_active; |
412 | unsigned long num_allocations; | |
413 | unsigned long high_mark; | |
414 | unsigned long grown; | |
415 | unsigned long reaped; | |
416 | unsigned long errors; | |
417 | unsigned long max_freeable; | |
418 | unsigned long node_allocs; | |
419 | unsigned long node_frees; | |
420 | atomic_t allochit; | |
421 | atomic_t allocmiss; | |
422 | atomic_t freehit; | |
423 | atomic_t freemiss; | |
1da177e4 LT |
424 | #endif |
425 | #if DEBUG | |
3dafccf2 MS |
426 | /* |
427 | * If debugging is enabled, then the allocator can add additional | |
428 | * fields and/or padding to every object. buffer_size contains the total | |
429 | * object size including these internal fields, the following two | |
430 | * variables contain the offset to the user object and its size. | |
431 | */ | |
432 | int obj_offset; | |
433 | int obj_size; | |
1da177e4 LT |
434 | #endif |
435 | }; | |
436 | ||
437 | #define CFLGS_OFF_SLAB (0x80000000UL) | |
438 | #define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) | |
439 | ||
440 | #define BATCHREFILL_LIMIT 16 | |
441 | /* Optimization question: fewer reaps means less | |
442 | * probability for unnessary cpucache drain/refill cycles. | |
443 | * | |
dc6f3f27 | 444 | * OTOH the cpuarrays can contain lots of objects, |
1da177e4 LT |
445 | * which could lock up otherwise freeable slabs. |
446 | */ | |
447 | #define REAPTIMEOUT_CPUC (2*HZ) | |
448 | #define REAPTIMEOUT_LIST3 (4*HZ) | |
449 | ||
450 | #if STATS | |
451 | #define STATS_INC_ACTIVE(x) ((x)->num_active++) | |
452 | #define STATS_DEC_ACTIVE(x) ((x)->num_active--) | |
453 | #define STATS_INC_ALLOCED(x) ((x)->num_allocations++) | |
454 | #define STATS_INC_GROWN(x) ((x)->grown++) | |
455 | #define STATS_INC_REAPED(x) ((x)->reaped++) | |
456 | #define STATS_SET_HIGH(x) do { if ((x)->num_active > (x)->high_mark) \ | |
457 | (x)->high_mark = (x)->num_active; \ | |
458 | } while (0) | |
459 | #define STATS_INC_ERR(x) ((x)->errors++) | |
460 | #define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) | |
e498be7d | 461 | #define STATS_INC_NODEFREES(x) ((x)->node_frees++) |
1da177e4 LT |
462 | #define STATS_SET_FREEABLE(x, i) \ |
463 | do { if ((x)->max_freeable < i) \ | |
464 | (x)->max_freeable = i; \ | |
465 | } while (0) | |
466 | ||
467 | #define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) | |
468 | #define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) | |
469 | #define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) | |
470 | #define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) | |
471 | #else | |
472 | #define STATS_INC_ACTIVE(x) do { } while (0) | |
473 | #define STATS_DEC_ACTIVE(x) do { } while (0) | |
474 | #define STATS_INC_ALLOCED(x) do { } while (0) | |
475 | #define STATS_INC_GROWN(x) do { } while (0) | |
476 | #define STATS_INC_REAPED(x) do { } while (0) | |
477 | #define STATS_SET_HIGH(x) do { } while (0) | |
478 | #define STATS_INC_ERR(x) do { } while (0) | |
479 | #define STATS_INC_NODEALLOCS(x) do { } while (0) | |
e498be7d | 480 | #define STATS_INC_NODEFREES(x) do { } while (0) |
1da177e4 LT |
481 | #define STATS_SET_FREEABLE(x, i) \ |
482 | do { } while (0) | |
483 | ||
484 | #define STATS_INC_ALLOCHIT(x) do { } while (0) | |
485 | #define STATS_INC_ALLOCMISS(x) do { } while (0) | |
486 | #define STATS_INC_FREEHIT(x) do { } while (0) | |
487 | #define STATS_INC_FREEMISS(x) do { } while (0) | |
488 | #endif | |
489 | ||
490 | #if DEBUG | |
491 | /* Magic nums for obj red zoning. | |
492 | * Placed in the first word before and the first word after an obj. | |
493 | */ | |
494 | #define RED_INACTIVE 0x5A2CF071UL /* when obj is inactive */ | |
495 | #define RED_ACTIVE 0x170FC2A5UL /* when obj is active */ | |
496 | ||
497 | /* ...and for poisoning */ | |
498 | #define POISON_INUSE 0x5a /* for use-uninitialised poisoning */ | |
499 | #define POISON_FREE 0x6b /* for use-after-free poisoning */ | |
500 | #define POISON_END 0xa5 /* end-byte of poisoning */ | |
501 | ||
502 | /* memory layout of objects: | |
503 | * 0 : objp | |
3dafccf2 | 504 | * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that |
1da177e4 LT |
505 | * the end of an object is aligned with the end of the real |
506 | * allocation. Catches writes behind the end of the allocation. | |
3dafccf2 | 507 | * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1: |
1da177e4 | 508 | * redzone word. |
3dafccf2 MS |
509 | * cachep->obj_offset: The real object. |
510 | * cachep->buffer_size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long] | |
511 | * cachep->buffer_size - 1* BYTES_PER_WORD: last caller address [BYTES_PER_WORD long] | |
1da177e4 | 512 | */ |
343e0d7a | 513 | static int obj_offset(struct kmem_cache *cachep) |
1da177e4 | 514 | { |
3dafccf2 | 515 | return cachep->obj_offset; |
1da177e4 LT |
516 | } |
517 | ||
343e0d7a | 518 | static int obj_size(struct kmem_cache *cachep) |
1da177e4 | 519 | { |
3dafccf2 | 520 | return cachep->obj_size; |
1da177e4 LT |
521 | } |
522 | ||
343e0d7a | 523 | static unsigned long *dbg_redzone1(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
524 | { |
525 | BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); | |
3dafccf2 | 526 | return (unsigned long*) (objp+obj_offset(cachep)-BYTES_PER_WORD); |
1da177e4 LT |
527 | } |
528 | ||
343e0d7a | 529 | static unsigned long *dbg_redzone2(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
530 | { |
531 | BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); | |
532 | if (cachep->flags & SLAB_STORE_USER) | |
3dafccf2 | 533 | return (unsigned long *)(objp + cachep->buffer_size - |
b28a02de | 534 | 2 * BYTES_PER_WORD); |
3dafccf2 | 535 | return (unsigned long *)(objp + cachep->buffer_size - BYTES_PER_WORD); |
1da177e4 LT |
536 | } |
537 | ||
343e0d7a | 538 | static void **dbg_userword(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
539 | { |
540 | BUG_ON(!(cachep->flags & SLAB_STORE_USER)); | |
3dafccf2 | 541 | return (void **)(objp + cachep->buffer_size - BYTES_PER_WORD); |
1da177e4 LT |
542 | } |
543 | ||
544 | #else | |
545 | ||
3dafccf2 MS |
546 | #define obj_offset(x) 0 |
547 | #define obj_size(cachep) (cachep->buffer_size) | |
1da177e4 LT |
548 | #define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long *)NULL;}) |
549 | #define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long *)NULL;}) | |
550 | #define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;}) | |
551 | ||
552 | #endif | |
553 | ||
554 | /* | |
555 | * Maximum size of an obj (in 2^order pages) | |
556 | * and absolute limit for the gfp order. | |
557 | */ | |
558 | #if defined(CONFIG_LARGE_ALLOCS) | |
559 | #define MAX_OBJ_ORDER 13 /* up to 32Mb */ | |
560 | #define MAX_GFP_ORDER 13 /* up to 32Mb */ | |
561 | #elif defined(CONFIG_MMU) | |
562 | #define MAX_OBJ_ORDER 5 /* 32 pages */ | |
563 | #define MAX_GFP_ORDER 5 /* 32 pages */ | |
564 | #else | |
565 | #define MAX_OBJ_ORDER 8 /* up to 1Mb */ | |
566 | #define MAX_GFP_ORDER 8 /* up to 1Mb */ | |
567 | #endif | |
568 | ||
569 | /* | |
570 | * Do not go above this order unless 0 objects fit into the slab. | |
571 | */ | |
572 | #define BREAK_GFP_ORDER_HI 1 | |
573 | #define BREAK_GFP_ORDER_LO 0 | |
574 | static int slab_break_gfp_order = BREAK_GFP_ORDER_LO; | |
575 | ||
065d41cb | 576 | /* Functions for storing/retrieving the cachep and or slab from the |
1da177e4 LT |
577 | * global 'mem_map'. These are used to find the slab an obj belongs to. |
578 | * With kfree(), these are used to find the cache which an obj belongs to. | |
579 | */ | |
065d41cb PE |
580 | static inline void page_set_cache(struct page *page, struct kmem_cache *cache) |
581 | { | |
582 | page->lru.next = (struct list_head *)cache; | |
583 | } | |
584 | ||
585 | static inline struct kmem_cache *page_get_cache(struct page *page) | |
586 | { | |
587 | return (struct kmem_cache *)page->lru.next; | |
588 | } | |
589 | ||
590 | static inline void page_set_slab(struct page *page, struct slab *slab) | |
591 | { | |
592 | page->lru.prev = (struct list_head *)slab; | |
593 | } | |
594 | ||
595 | static inline struct slab *page_get_slab(struct page *page) | |
596 | { | |
597 | return (struct slab *)page->lru.prev; | |
598 | } | |
1da177e4 | 599 | |
6ed5eb22 PE |
600 | static inline struct kmem_cache *virt_to_cache(const void *obj) |
601 | { | |
602 | struct page *page = virt_to_page(obj); | |
603 | return page_get_cache(page); | |
604 | } | |
605 | ||
606 | static inline struct slab *virt_to_slab(const void *obj) | |
607 | { | |
608 | struct page *page = virt_to_page(obj); | |
609 | return page_get_slab(page); | |
610 | } | |
611 | ||
1da177e4 LT |
612 | /* These are the default caches for kmalloc. Custom caches can have other sizes. */ |
613 | struct cache_sizes malloc_sizes[] = { | |
614 | #define CACHE(x) { .cs_size = (x) }, | |
615 | #include <linux/kmalloc_sizes.h> | |
616 | CACHE(ULONG_MAX) | |
617 | #undef CACHE | |
618 | }; | |
619 | EXPORT_SYMBOL(malloc_sizes); | |
620 | ||
621 | /* Must match cache_sizes above. Out of line to keep cache footprint low. */ | |
622 | struct cache_names { | |
623 | char *name; | |
624 | char *name_dma; | |
625 | }; | |
626 | ||
627 | static struct cache_names __initdata cache_names[] = { | |
628 | #define CACHE(x) { .name = "size-" #x, .name_dma = "size-" #x "(DMA)" }, | |
629 | #include <linux/kmalloc_sizes.h> | |
b28a02de | 630 | {NULL,} |
1da177e4 LT |
631 | #undef CACHE |
632 | }; | |
633 | ||
634 | static struct arraycache_init initarray_cache __initdata = | |
b28a02de | 635 | { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; |
1da177e4 | 636 | static struct arraycache_init initarray_generic = |
b28a02de | 637 | { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; |
1da177e4 LT |
638 | |
639 | /* internal cache of cache description objs */ | |
343e0d7a | 640 | static struct kmem_cache cache_cache = { |
b28a02de PE |
641 | .batchcount = 1, |
642 | .limit = BOOT_CPUCACHE_ENTRIES, | |
643 | .shared = 1, | |
343e0d7a | 644 | .buffer_size = sizeof(struct kmem_cache), |
b28a02de PE |
645 | .flags = SLAB_NO_REAP, |
646 | .spinlock = SPIN_LOCK_UNLOCKED, | |
647 | .name = "kmem_cache", | |
1da177e4 | 648 | #if DEBUG |
343e0d7a | 649 | .obj_size = sizeof(struct kmem_cache), |
1da177e4 LT |
650 | #endif |
651 | }; | |
652 | ||
653 | /* Guard access to the cache-chain. */ | |
fc0abb14 | 654 | static DEFINE_MUTEX(cache_chain_mutex); |
1da177e4 LT |
655 | static struct list_head cache_chain; |
656 | ||
657 | /* | |
658 | * vm_enough_memory() looks at this to determine how many | |
659 | * slab-allocated pages are possibly freeable under pressure | |
660 | * | |
661 | * SLAB_RECLAIM_ACCOUNT turns this on per-slab | |
662 | */ | |
663 | atomic_t slab_reclaim_pages; | |
1da177e4 LT |
664 | |
665 | /* | |
666 | * chicken and egg problem: delay the per-cpu array allocation | |
667 | * until the general caches are up. | |
668 | */ | |
669 | static enum { | |
670 | NONE, | |
e498be7d CL |
671 | PARTIAL_AC, |
672 | PARTIAL_L3, | |
1da177e4 LT |
673 | FULL |
674 | } g_cpucache_up; | |
675 | ||
676 | static DEFINE_PER_CPU(struct work_struct, reap_work); | |
677 | ||
343e0d7a PE |
678 | static void free_block(struct kmem_cache *cachep, void **objpp, int len, int node); |
679 | static void enable_cpucache(struct kmem_cache *cachep); | |
b28a02de | 680 | static void cache_reap(void *unused); |
343e0d7a | 681 | static int __node_shrink(struct kmem_cache *cachep, int node); |
1da177e4 | 682 | |
343e0d7a | 683 | static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep) |
1da177e4 LT |
684 | { |
685 | return cachep->array[smp_processor_id()]; | |
686 | } | |
687 | ||
343e0d7a | 688 | static inline struct kmem_cache *__find_general_cachep(size_t size, gfp_t gfpflags) |
1da177e4 LT |
689 | { |
690 | struct cache_sizes *csizep = malloc_sizes; | |
691 | ||
692 | #if DEBUG | |
693 | /* This happens if someone tries to call | |
b28a02de PE |
694 | * kmem_cache_create(), or __kmalloc(), before |
695 | * the generic caches are initialized. | |
696 | */ | |
c7e43c78 | 697 | BUG_ON(malloc_sizes[INDEX_AC].cs_cachep == NULL); |
1da177e4 LT |
698 | #endif |
699 | while (size > csizep->cs_size) | |
700 | csizep++; | |
701 | ||
702 | /* | |
0abf40c1 | 703 | * Really subtle: The last entry with cs->cs_size==ULONG_MAX |
1da177e4 LT |
704 | * has cs_{dma,}cachep==NULL. Thus no special case |
705 | * for large kmalloc calls required. | |
706 | */ | |
707 | if (unlikely(gfpflags & GFP_DMA)) | |
708 | return csizep->cs_dmacachep; | |
709 | return csizep->cs_cachep; | |
710 | } | |
711 | ||
343e0d7a | 712 | struct kmem_cache *kmem_find_general_cachep(size_t size, gfp_t gfpflags) |
97e2bde4 MS |
713 | { |
714 | return __find_general_cachep(size, gfpflags); | |
715 | } | |
716 | EXPORT_SYMBOL(kmem_find_general_cachep); | |
717 | ||
fbaccacf | 718 | static size_t slab_mgmt_size(size_t nr_objs, size_t align) |
1da177e4 | 719 | { |
fbaccacf SR |
720 | return ALIGN(sizeof(struct slab)+nr_objs*sizeof(kmem_bufctl_t), align); |
721 | } | |
1da177e4 | 722 | |
fbaccacf SR |
723 | /* Calculate the number of objects and left-over bytes for a given |
724 | buffer size. */ | |
725 | static void cache_estimate(unsigned long gfporder, size_t buffer_size, | |
726 | size_t align, int flags, size_t *left_over, | |
727 | unsigned int *num) | |
728 | { | |
729 | int nr_objs; | |
730 | size_t mgmt_size; | |
731 | size_t slab_size = PAGE_SIZE << gfporder; | |
1da177e4 | 732 | |
fbaccacf SR |
733 | /* |
734 | * The slab management structure can be either off the slab or | |
735 | * on it. For the latter case, the memory allocated for a | |
736 | * slab is used for: | |
737 | * | |
738 | * - The struct slab | |
739 | * - One kmem_bufctl_t for each object | |
740 | * - Padding to respect alignment of @align | |
741 | * - @buffer_size bytes for each object | |
742 | * | |
743 | * If the slab management structure is off the slab, then the | |
744 | * alignment will already be calculated into the size. Because | |
745 | * the slabs are all pages aligned, the objects will be at the | |
746 | * correct alignment when allocated. | |
747 | */ | |
748 | if (flags & CFLGS_OFF_SLAB) { | |
749 | mgmt_size = 0; | |
750 | nr_objs = slab_size / buffer_size; | |
751 | ||
752 | if (nr_objs > SLAB_LIMIT) | |
753 | nr_objs = SLAB_LIMIT; | |
754 | } else { | |
755 | /* | |
756 | * Ignore padding for the initial guess. The padding | |
757 | * is at most @align-1 bytes, and @buffer_size is at | |
758 | * least @align. In the worst case, this result will | |
759 | * be one greater than the number of objects that fit | |
760 | * into the memory allocation when taking the padding | |
761 | * into account. | |
762 | */ | |
763 | nr_objs = (slab_size - sizeof(struct slab)) / | |
764 | (buffer_size + sizeof(kmem_bufctl_t)); | |
765 | ||
766 | /* | |
767 | * This calculated number will be either the right | |
768 | * amount, or one greater than what we want. | |
769 | */ | |
770 | if (slab_mgmt_size(nr_objs, align) + nr_objs*buffer_size | |
771 | > slab_size) | |
772 | nr_objs--; | |
773 | ||
774 | if (nr_objs > SLAB_LIMIT) | |
775 | nr_objs = SLAB_LIMIT; | |
776 | ||
777 | mgmt_size = slab_mgmt_size(nr_objs, align); | |
778 | } | |
779 | *num = nr_objs; | |
780 | *left_over = slab_size - nr_objs*buffer_size - mgmt_size; | |
1da177e4 LT |
781 | } |
782 | ||
783 | #define slab_error(cachep, msg) __slab_error(__FUNCTION__, cachep, msg) | |
784 | ||
343e0d7a | 785 | static void __slab_error(const char *function, struct kmem_cache *cachep, char *msg) |
1da177e4 LT |
786 | { |
787 | printk(KERN_ERR "slab error in %s(): cache `%s': %s\n", | |
b28a02de | 788 | function, cachep->name, msg); |
1da177e4 LT |
789 | dump_stack(); |
790 | } | |
791 | ||
792 | /* | |
793 | * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz | |
794 | * via the workqueue/eventd. | |
795 | * Add the CPU number into the expiration time to minimize the possibility of | |
796 | * the CPUs getting into lockstep and contending for the global cache chain | |
797 | * lock. | |
798 | */ | |
799 | static void __devinit start_cpu_timer(int cpu) | |
800 | { | |
801 | struct work_struct *reap_work = &per_cpu(reap_work, cpu); | |
802 | ||
803 | /* | |
804 | * When this gets called from do_initcalls via cpucache_init(), | |
805 | * init_workqueues() has already run, so keventd will be setup | |
806 | * at that time. | |
807 | */ | |
808 | if (keventd_up() && reap_work->func == NULL) { | |
809 | INIT_WORK(reap_work, cache_reap, NULL); | |
810 | schedule_delayed_work_on(cpu, reap_work, HZ + 3 * cpu); | |
811 | } | |
812 | } | |
813 | ||
e498be7d | 814 | static struct array_cache *alloc_arraycache(int node, int entries, |
b28a02de | 815 | int batchcount) |
1da177e4 | 816 | { |
b28a02de | 817 | int memsize = sizeof(void *) * entries + sizeof(struct array_cache); |
1da177e4 LT |
818 | struct array_cache *nc = NULL; |
819 | ||
e498be7d | 820 | nc = kmalloc_node(memsize, GFP_KERNEL, node); |
1da177e4 LT |
821 | if (nc) { |
822 | nc->avail = 0; | |
823 | nc->limit = entries; | |
824 | nc->batchcount = batchcount; | |
825 | nc->touched = 0; | |
e498be7d | 826 | spin_lock_init(&nc->lock); |
1da177e4 LT |
827 | } |
828 | return nc; | |
829 | } | |
830 | ||
e498be7d | 831 | #ifdef CONFIG_NUMA |
343e0d7a | 832 | static void *__cache_alloc_node(struct kmem_cache *, gfp_t, int); |
dc85da15 | 833 | |
5295a74c | 834 | static struct array_cache **alloc_alien_cache(int node, int limit) |
e498be7d CL |
835 | { |
836 | struct array_cache **ac_ptr; | |
b28a02de | 837 | int memsize = sizeof(void *) * MAX_NUMNODES; |
e498be7d CL |
838 | int i; |
839 | ||
840 | if (limit > 1) | |
841 | limit = 12; | |
842 | ac_ptr = kmalloc_node(memsize, GFP_KERNEL, node); | |
843 | if (ac_ptr) { | |
844 | for_each_node(i) { | |
845 | if (i == node || !node_online(i)) { | |
846 | ac_ptr[i] = NULL; | |
847 | continue; | |
848 | } | |
849 | ac_ptr[i] = alloc_arraycache(node, limit, 0xbaadf00d); | |
850 | if (!ac_ptr[i]) { | |
b28a02de | 851 | for (i--; i <= 0; i--) |
e498be7d CL |
852 | kfree(ac_ptr[i]); |
853 | kfree(ac_ptr); | |
854 | return NULL; | |
855 | } | |
856 | } | |
857 | } | |
858 | return ac_ptr; | |
859 | } | |
860 | ||
5295a74c | 861 | static void free_alien_cache(struct array_cache **ac_ptr) |
e498be7d CL |
862 | { |
863 | int i; | |
864 | ||
865 | if (!ac_ptr) | |
866 | return; | |
867 | ||
868 | for_each_node(i) | |
b28a02de | 869 | kfree(ac_ptr[i]); |
e498be7d CL |
870 | |
871 | kfree(ac_ptr); | |
872 | } | |
873 | ||
343e0d7a | 874 | static void __drain_alien_cache(struct kmem_cache *cachep, |
5295a74c | 875 | struct array_cache *ac, int node) |
e498be7d CL |
876 | { |
877 | struct kmem_list3 *rl3 = cachep->nodelists[node]; | |
878 | ||
879 | if (ac->avail) { | |
880 | spin_lock(&rl3->list_lock); | |
ff69416e | 881 | free_block(cachep, ac->entry, ac->avail, node); |
e498be7d CL |
882 | ac->avail = 0; |
883 | spin_unlock(&rl3->list_lock); | |
884 | } | |
885 | } | |
886 | ||
343e0d7a | 887 | static void drain_alien_cache(struct kmem_cache *cachep, struct kmem_list3 *l3) |
e498be7d | 888 | { |
b28a02de | 889 | int i = 0; |
e498be7d CL |
890 | struct array_cache *ac; |
891 | unsigned long flags; | |
892 | ||
893 | for_each_online_node(i) { | |
894 | ac = l3->alien[i]; | |
895 | if (ac) { | |
896 | spin_lock_irqsave(&ac->lock, flags); | |
897 | __drain_alien_cache(cachep, ac, i); | |
898 | spin_unlock_irqrestore(&ac->lock, flags); | |
899 | } | |
900 | } | |
901 | } | |
902 | #else | |
903 | #define alloc_alien_cache(node, limit) do { } while (0) | |
904 | #define free_alien_cache(ac_ptr) do { } while (0) | |
905 | #define drain_alien_cache(cachep, l3) do { } while (0) | |
906 | #endif | |
907 | ||
1da177e4 | 908 | static int __devinit cpuup_callback(struct notifier_block *nfb, |
b28a02de | 909 | unsigned long action, void *hcpu) |
1da177e4 LT |
910 | { |
911 | long cpu = (long)hcpu; | |
343e0d7a | 912 | struct kmem_cache *cachep; |
e498be7d CL |
913 | struct kmem_list3 *l3 = NULL; |
914 | int node = cpu_to_node(cpu); | |
915 | int memsize = sizeof(struct kmem_list3); | |
1da177e4 LT |
916 | |
917 | switch (action) { | |
918 | case CPU_UP_PREPARE: | |
fc0abb14 | 919 | mutex_lock(&cache_chain_mutex); |
e498be7d CL |
920 | /* we need to do this right in the beginning since |
921 | * alloc_arraycache's are going to use this list. | |
922 | * kmalloc_node allows us to add the slab to the right | |
923 | * kmem_list3 and not this cpu's kmem_list3 | |
924 | */ | |
925 | ||
1da177e4 | 926 | list_for_each_entry(cachep, &cache_chain, next) { |
e498be7d CL |
927 | /* setup the size64 kmemlist for cpu before we can |
928 | * begin anything. Make sure some other cpu on this | |
929 | * node has not already allocated this | |
930 | */ | |
931 | if (!cachep->nodelists[node]) { | |
932 | if (!(l3 = kmalloc_node(memsize, | |
b28a02de | 933 | GFP_KERNEL, node))) |
e498be7d CL |
934 | goto bad; |
935 | kmem_list3_init(l3); | |
936 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + | |
b28a02de | 937 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
e498be7d CL |
938 | |
939 | cachep->nodelists[node] = l3; | |
940 | } | |
1da177e4 | 941 | |
e498be7d CL |
942 | spin_lock_irq(&cachep->nodelists[node]->list_lock); |
943 | cachep->nodelists[node]->free_limit = | |
b28a02de PE |
944 | (1 + nr_cpus_node(node)) * |
945 | cachep->batchcount + cachep->num; | |
e498be7d CL |
946 | spin_unlock_irq(&cachep->nodelists[node]->list_lock); |
947 | } | |
948 | ||
949 | /* Now we can go ahead with allocating the shared array's | |
b28a02de | 950 | & array cache's */ |
e498be7d | 951 | list_for_each_entry(cachep, &cache_chain, next) { |
cd105df4 TK |
952 | struct array_cache *nc; |
953 | ||
e498be7d | 954 | nc = alloc_arraycache(node, cachep->limit, |
b28a02de | 955 | cachep->batchcount); |
1da177e4 LT |
956 | if (!nc) |
957 | goto bad; | |
1da177e4 | 958 | cachep->array[cpu] = nc; |
1da177e4 | 959 | |
e498be7d CL |
960 | l3 = cachep->nodelists[node]; |
961 | BUG_ON(!l3); | |
962 | if (!l3->shared) { | |
963 | if (!(nc = alloc_arraycache(node, | |
b28a02de PE |
964 | cachep->shared * |
965 | cachep->batchcount, | |
966 | 0xbaadf00d))) | |
967 | goto bad; | |
e498be7d CL |
968 | |
969 | /* we are serialised from CPU_DEAD or | |
b28a02de | 970 | CPU_UP_CANCELLED by the cpucontrol lock */ |
e498be7d CL |
971 | l3->shared = nc; |
972 | } | |
1da177e4 | 973 | } |
fc0abb14 | 974 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
975 | break; |
976 | case CPU_ONLINE: | |
977 | start_cpu_timer(cpu); | |
978 | break; | |
979 | #ifdef CONFIG_HOTPLUG_CPU | |
980 | case CPU_DEAD: | |
981 | /* fall thru */ | |
982 | case CPU_UP_CANCELED: | |
fc0abb14 | 983 | mutex_lock(&cache_chain_mutex); |
1da177e4 LT |
984 | |
985 | list_for_each_entry(cachep, &cache_chain, next) { | |
986 | struct array_cache *nc; | |
e498be7d | 987 | cpumask_t mask; |
1da177e4 | 988 | |
e498be7d | 989 | mask = node_to_cpumask(node); |
1da177e4 LT |
990 | spin_lock_irq(&cachep->spinlock); |
991 | /* cpu is dead; no one can alloc from it. */ | |
992 | nc = cachep->array[cpu]; | |
993 | cachep->array[cpu] = NULL; | |
e498be7d CL |
994 | l3 = cachep->nodelists[node]; |
995 | ||
996 | if (!l3) | |
997 | goto unlock_cache; | |
998 | ||
999 | spin_lock(&l3->list_lock); | |
1000 | ||
1001 | /* Free limit for this kmem_list3 */ | |
1002 | l3->free_limit -= cachep->batchcount; | |
1003 | if (nc) | |
ff69416e | 1004 | free_block(cachep, nc->entry, nc->avail, node); |
e498be7d CL |
1005 | |
1006 | if (!cpus_empty(mask)) { | |
b28a02de PE |
1007 | spin_unlock(&l3->list_lock); |
1008 | goto unlock_cache; | |
1009 | } | |
e498be7d CL |
1010 | |
1011 | if (l3->shared) { | |
1012 | free_block(cachep, l3->shared->entry, | |
b28a02de | 1013 | l3->shared->avail, node); |
e498be7d CL |
1014 | kfree(l3->shared); |
1015 | l3->shared = NULL; | |
1016 | } | |
1017 | if (l3->alien) { | |
1018 | drain_alien_cache(cachep, l3); | |
1019 | free_alien_cache(l3->alien); | |
1020 | l3->alien = NULL; | |
1021 | } | |
1022 | ||
1023 | /* free slabs belonging to this node */ | |
1024 | if (__node_shrink(cachep, node)) { | |
1025 | cachep->nodelists[node] = NULL; | |
1026 | spin_unlock(&l3->list_lock); | |
1027 | kfree(l3); | |
1028 | } else { | |
1029 | spin_unlock(&l3->list_lock); | |
1030 | } | |
b28a02de | 1031 | unlock_cache: |
1da177e4 LT |
1032 | spin_unlock_irq(&cachep->spinlock); |
1033 | kfree(nc); | |
1034 | } | |
fc0abb14 | 1035 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1036 | break; |
1037 | #endif | |
1038 | } | |
1039 | return NOTIFY_OK; | |
b28a02de | 1040 | bad: |
fc0abb14 | 1041 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1042 | return NOTIFY_BAD; |
1043 | } | |
1044 | ||
1045 | static struct notifier_block cpucache_notifier = { &cpuup_callback, NULL, 0 }; | |
1046 | ||
e498be7d CL |
1047 | /* |
1048 | * swap the static kmem_list3 with kmalloced memory | |
1049 | */ | |
343e0d7a | 1050 | static void init_list(struct kmem_cache *cachep, struct kmem_list3 *list, int nodeid) |
e498be7d CL |
1051 | { |
1052 | struct kmem_list3 *ptr; | |
1053 | ||
1054 | BUG_ON(cachep->nodelists[nodeid] != list); | |
1055 | ptr = kmalloc_node(sizeof(struct kmem_list3), GFP_KERNEL, nodeid); | |
1056 | BUG_ON(!ptr); | |
1057 | ||
1058 | local_irq_disable(); | |
1059 | memcpy(ptr, list, sizeof(struct kmem_list3)); | |
1060 | MAKE_ALL_LISTS(cachep, ptr, nodeid); | |
1061 | cachep->nodelists[nodeid] = ptr; | |
1062 | local_irq_enable(); | |
1063 | } | |
1064 | ||
1da177e4 LT |
1065 | /* Initialisation. |
1066 | * Called after the gfp() functions have been enabled, and before smp_init(). | |
1067 | */ | |
1068 | void __init kmem_cache_init(void) | |
1069 | { | |
1070 | size_t left_over; | |
1071 | struct cache_sizes *sizes; | |
1072 | struct cache_names *names; | |
e498be7d CL |
1073 | int i; |
1074 | ||
1075 | for (i = 0; i < NUM_INIT_LISTS; i++) { | |
1076 | kmem_list3_init(&initkmem_list3[i]); | |
1077 | if (i < MAX_NUMNODES) | |
1078 | cache_cache.nodelists[i] = NULL; | |
1079 | } | |
1da177e4 LT |
1080 | |
1081 | /* | |
1082 | * Fragmentation resistance on low memory - only use bigger | |
1083 | * page orders on machines with more than 32MB of memory. | |
1084 | */ | |
1085 | if (num_physpages > (32 << 20) >> PAGE_SHIFT) | |
1086 | slab_break_gfp_order = BREAK_GFP_ORDER_HI; | |
1087 | ||
1da177e4 LT |
1088 | /* Bootstrap is tricky, because several objects are allocated |
1089 | * from caches that do not exist yet: | |
343e0d7a | 1090 | * 1) initialize the cache_cache cache: it contains the struct kmem_cache |
1da177e4 LT |
1091 | * structures of all caches, except cache_cache itself: cache_cache |
1092 | * is statically allocated. | |
e498be7d CL |
1093 | * Initially an __init data area is used for the head array and the |
1094 | * kmem_list3 structures, it's replaced with a kmalloc allocated | |
1095 | * array at the end of the bootstrap. | |
1da177e4 | 1096 | * 2) Create the first kmalloc cache. |
343e0d7a | 1097 | * The struct kmem_cache for the new cache is allocated normally. |
e498be7d CL |
1098 | * An __init data area is used for the head array. |
1099 | * 3) Create the remaining kmalloc caches, with minimally sized | |
1100 | * head arrays. | |
1da177e4 LT |
1101 | * 4) Replace the __init data head arrays for cache_cache and the first |
1102 | * kmalloc cache with kmalloc allocated arrays. | |
e498be7d CL |
1103 | * 5) Replace the __init data for kmem_list3 for cache_cache and |
1104 | * the other cache's with kmalloc allocated memory. | |
1105 | * 6) Resize the head arrays of the kmalloc caches to their final sizes. | |
1da177e4 LT |
1106 | */ |
1107 | ||
1108 | /* 1) create the cache_cache */ | |
1da177e4 LT |
1109 | INIT_LIST_HEAD(&cache_chain); |
1110 | list_add(&cache_cache.next, &cache_chain); | |
1111 | cache_cache.colour_off = cache_line_size(); | |
1112 | cache_cache.array[smp_processor_id()] = &initarray_cache.cache; | |
e498be7d | 1113 | cache_cache.nodelists[numa_node_id()] = &initkmem_list3[CACHE_CACHE]; |
1da177e4 | 1114 | |
3dafccf2 | 1115 | cache_cache.buffer_size = ALIGN(cache_cache.buffer_size, cache_line_size()); |
1da177e4 | 1116 | |
3dafccf2 | 1117 | cache_estimate(0, cache_cache.buffer_size, cache_line_size(), 0, |
b28a02de | 1118 | &left_over, &cache_cache.num); |
1da177e4 LT |
1119 | if (!cache_cache.num) |
1120 | BUG(); | |
1121 | ||
b28a02de | 1122 | cache_cache.colour = left_over / cache_cache.colour_off; |
b28a02de PE |
1123 | cache_cache.slab_size = ALIGN(cache_cache.num * sizeof(kmem_bufctl_t) + |
1124 | sizeof(struct slab), cache_line_size()); | |
1da177e4 LT |
1125 | |
1126 | /* 2+3) create the kmalloc caches */ | |
1127 | sizes = malloc_sizes; | |
1128 | names = cache_names; | |
1129 | ||
e498be7d CL |
1130 | /* Initialize the caches that provide memory for the array cache |
1131 | * and the kmem_list3 structures first. | |
1132 | * Without this, further allocations will bug | |
1133 | */ | |
1134 | ||
1135 | sizes[INDEX_AC].cs_cachep = kmem_cache_create(names[INDEX_AC].name, | |
b28a02de PE |
1136 | sizes[INDEX_AC].cs_size, |
1137 | ARCH_KMALLOC_MINALIGN, | |
1138 | (ARCH_KMALLOC_FLAGS | | |
1139 | SLAB_PANIC), NULL, NULL); | |
e498be7d CL |
1140 | |
1141 | if (INDEX_AC != INDEX_L3) | |
1142 | sizes[INDEX_L3].cs_cachep = | |
b28a02de PE |
1143 | kmem_cache_create(names[INDEX_L3].name, |
1144 | sizes[INDEX_L3].cs_size, | |
1145 | ARCH_KMALLOC_MINALIGN, | |
1146 | (ARCH_KMALLOC_FLAGS | SLAB_PANIC), NULL, | |
1147 | NULL); | |
e498be7d | 1148 | |
1da177e4 | 1149 | while (sizes->cs_size != ULONG_MAX) { |
e498be7d CL |
1150 | /* |
1151 | * For performance, all the general caches are L1 aligned. | |
1da177e4 LT |
1152 | * This should be particularly beneficial on SMP boxes, as it |
1153 | * eliminates "false sharing". | |
1154 | * Note for systems short on memory removing the alignment will | |
e498be7d CL |
1155 | * allow tighter packing of the smaller caches. |
1156 | */ | |
b28a02de | 1157 | if (!sizes->cs_cachep) |
e498be7d | 1158 | sizes->cs_cachep = kmem_cache_create(names->name, |
b28a02de PE |
1159 | sizes->cs_size, |
1160 | ARCH_KMALLOC_MINALIGN, | |
1161 | (ARCH_KMALLOC_FLAGS | |
1162 | | SLAB_PANIC), | |
1163 | NULL, NULL); | |
1da177e4 LT |
1164 | |
1165 | /* Inc off-slab bufctl limit until the ceiling is hit. */ | |
1166 | if (!(OFF_SLAB(sizes->cs_cachep))) { | |
b28a02de | 1167 | offslab_limit = sizes->cs_size - sizeof(struct slab); |
1da177e4 LT |
1168 | offslab_limit /= sizeof(kmem_bufctl_t); |
1169 | } | |
1170 | ||
1171 | sizes->cs_dmacachep = kmem_cache_create(names->name_dma, | |
b28a02de PE |
1172 | sizes->cs_size, |
1173 | ARCH_KMALLOC_MINALIGN, | |
1174 | (ARCH_KMALLOC_FLAGS | | |
1175 | SLAB_CACHE_DMA | | |
1176 | SLAB_PANIC), NULL, | |
1177 | NULL); | |
1da177e4 LT |
1178 | |
1179 | sizes++; | |
1180 | names++; | |
1181 | } | |
1182 | /* 4) Replace the bootstrap head arrays */ | |
1183 | { | |
b28a02de | 1184 | void *ptr; |
e498be7d | 1185 | |
1da177e4 | 1186 | ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d | 1187 | |
1da177e4 | 1188 | local_irq_disable(); |
9a2dba4b PE |
1189 | BUG_ON(cpu_cache_get(&cache_cache) != &initarray_cache.cache); |
1190 | memcpy(ptr, cpu_cache_get(&cache_cache), | |
b28a02de | 1191 | sizeof(struct arraycache_init)); |
1da177e4 LT |
1192 | cache_cache.array[smp_processor_id()] = ptr; |
1193 | local_irq_enable(); | |
e498be7d | 1194 | |
1da177e4 | 1195 | ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d | 1196 | |
1da177e4 | 1197 | local_irq_disable(); |
9a2dba4b | 1198 | BUG_ON(cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep) |
b28a02de | 1199 | != &initarray_generic.cache); |
9a2dba4b | 1200 | memcpy(ptr, cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep), |
b28a02de | 1201 | sizeof(struct arraycache_init)); |
e498be7d | 1202 | malloc_sizes[INDEX_AC].cs_cachep->array[smp_processor_id()] = |
b28a02de | 1203 | ptr; |
1da177e4 LT |
1204 | local_irq_enable(); |
1205 | } | |
e498be7d CL |
1206 | /* 5) Replace the bootstrap kmem_list3's */ |
1207 | { | |
1208 | int node; | |
1209 | /* Replace the static kmem_list3 structures for the boot cpu */ | |
1210 | init_list(&cache_cache, &initkmem_list3[CACHE_CACHE], | |
b28a02de | 1211 | numa_node_id()); |
e498be7d CL |
1212 | |
1213 | for_each_online_node(node) { | |
1214 | init_list(malloc_sizes[INDEX_AC].cs_cachep, | |
b28a02de | 1215 | &initkmem_list3[SIZE_AC + node], node); |
e498be7d CL |
1216 | |
1217 | if (INDEX_AC != INDEX_L3) { | |
1218 | init_list(malloc_sizes[INDEX_L3].cs_cachep, | |
b28a02de PE |
1219 | &initkmem_list3[SIZE_L3 + node], |
1220 | node); | |
e498be7d CL |
1221 | } |
1222 | } | |
1223 | } | |
1da177e4 | 1224 | |
e498be7d | 1225 | /* 6) resize the head arrays to their final sizes */ |
1da177e4 | 1226 | { |
343e0d7a | 1227 | struct kmem_cache *cachep; |
fc0abb14 | 1228 | mutex_lock(&cache_chain_mutex); |
1da177e4 | 1229 | list_for_each_entry(cachep, &cache_chain, next) |
b28a02de | 1230 | enable_cpucache(cachep); |
fc0abb14 | 1231 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1232 | } |
1233 | ||
1234 | /* Done! */ | |
1235 | g_cpucache_up = FULL; | |
1236 | ||
1237 | /* Register a cpu startup notifier callback | |
9a2dba4b | 1238 | * that initializes cpu_cache_get for all new cpus |
1da177e4 LT |
1239 | */ |
1240 | register_cpu_notifier(&cpucache_notifier); | |
1da177e4 LT |
1241 | |
1242 | /* The reap timers are started later, with a module init call: | |
1243 | * That part of the kernel is not yet operational. | |
1244 | */ | |
1245 | } | |
1246 | ||
1247 | static int __init cpucache_init(void) | |
1248 | { | |
1249 | int cpu; | |
1250 | ||
1251 | /* | |
1252 | * Register the timers that return unneeded | |
1253 | * pages to gfp. | |
1254 | */ | |
e498be7d | 1255 | for_each_online_cpu(cpu) |
b28a02de | 1256 | start_cpu_timer(cpu); |
1da177e4 LT |
1257 | |
1258 | return 0; | |
1259 | } | |
1260 | ||
1261 | __initcall(cpucache_init); | |
1262 | ||
1263 | /* | |
1264 | * Interface to system's page allocator. No need to hold the cache-lock. | |
1265 | * | |
1266 | * If we requested dmaable memory, we will get it. Even if we | |
1267 | * did not request dmaable memory, we might get it, but that | |
1268 | * would be relatively rare and ignorable. | |
1269 | */ | |
343e0d7a | 1270 | static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 LT |
1271 | { |
1272 | struct page *page; | |
1273 | void *addr; | |
1274 | int i; | |
1275 | ||
1276 | flags |= cachep->gfpflags; | |
50c85a19 | 1277 | page = alloc_pages_node(nodeid, flags, cachep->gfporder); |
1da177e4 LT |
1278 | if (!page) |
1279 | return NULL; | |
1280 | addr = page_address(page); | |
1281 | ||
1282 | i = (1 << cachep->gfporder); | |
1283 | if (cachep->flags & SLAB_RECLAIM_ACCOUNT) | |
1284 | atomic_add(i, &slab_reclaim_pages); | |
1285 | add_page_state(nr_slab, i); | |
1286 | while (i--) { | |
1287 | SetPageSlab(page); | |
1288 | page++; | |
1289 | } | |
1290 | return addr; | |
1291 | } | |
1292 | ||
1293 | /* | |
1294 | * Interface to system's page release. | |
1295 | */ | |
343e0d7a | 1296 | static void kmem_freepages(struct kmem_cache *cachep, void *addr) |
1da177e4 | 1297 | { |
b28a02de | 1298 | unsigned long i = (1 << cachep->gfporder); |
1da177e4 LT |
1299 | struct page *page = virt_to_page(addr); |
1300 | const unsigned long nr_freed = i; | |
1301 | ||
1302 | while (i--) { | |
1303 | if (!TestClearPageSlab(page)) | |
1304 | BUG(); | |
1305 | page++; | |
1306 | } | |
1307 | sub_page_state(nr_slab, nr_freed); | |
1308 | if (current->reclaim_state) | |
1309 | current->reclaim_state->reclaimed_slab += nr_freed; | |
1310 | free_pages((unsigned long)addr, cachep->gfporder); | |
b28a02de PE |
1311 | if (cachep->flags & SLAB_RECLAIM_ACCOUNT) |
1312 | atomic_sub(1 << cachep->gfporder, &slab_reclaim_pages); | |
1da177e4 LT |
1313 | } |
1314 | ||
1315 | static void kmem_rcu_free(struct rcu_head *head) | |
1316 | { | |
b28a02de | 1317 | struct slab_rcu *slab_rcu = (struct slab_rcu *)head; |
343e0d7a | 1318 | struct kmem_cache *cachep = slab_rcu->cachep; |
1da177e4 LT |
1319 | |
1320 | kmem_freepages(cachep, slab_rcu->addr); | |
1321 | if (OFF_SLAB(cachep)) | |
1322 | kmem_cache_free(cachep->slabp_cache, slab_rcu); | |
1323 | } | |
1324 | ||
1325 | #if DEBUG | |
1326 | ||
1327 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
343e0d7a | 1328 | static void store_stackinfo(struct kmem_cache *cachep, unsigned long *addr, |
b28a02de | 1329 | unsigned long caller) |
1da177e4 | 1330 | { |
3dafccf2 | 1331 | int size = obj_size(cachep); |
1da177e4 | 1332 | |
3dafccf2 | 1333 | addr = (unsigned long *)&((char *)addr)[obj_offset(cachep)]; |
1da177e4 | 1334 | |
b28a02de | 1335 | if (size < 5 * sizeof(unsigned long)) |
1da177e4 LT |
1336 | return; |
1337 | ||
b28a02de PE |
1338 | *addr++ = 0x12345678; |
1339 | *addr++ = caller; | |
1340 | *addr++ = smp_processor_id(); | |
1341 | size -= 3 * sizeof(unsigned long); | |
1da177e4 LT |
1342 | { |
1343 | unsigned long *sptr = &caller; | |
1344 | unsigned long svalue; | |
1345 | ||
1346 | while (!kstack_end(sptr)) { | |
1347 | svalue = *sptr++; | |
1348 | if (kernel_text_address(svalue)) { | |
b28a02de | 1349 | *addr++ = svalue; |
1da177e4 LT |
1350 | size -= sizeof(unsigned long); |
1351 | if (size <= sizeof(unsigned long)) | |
1352 | break; | |
1353 | } | |
1354 | } | |
1355 | ||
1356 | } | |
b28a02de | 1357 | *addr++ = 0x87654321; |
1da177e4 LT |
1358 | } |
1359 | #endif | |
1360 | ||
343e0d7a | 1361 | static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) |
1da177e4 | 1362 | { |
3dafccf2 MS |
1363 | int size = obj_size(cachep); |
1364 | addr = &((char *)addr)[obj_offset(cachep)]; | |
1da177e4 LT |
1365 | |
1366 | memset(addr, val, size); | |
b28a02de | 1367 | *(unsigned char *)(addr + size - 1) = POISON_END; |
1da177e4 LT |
1368 | } |
1369 | ||
1370 | static void dump_line(char *data, int offset, int limit) | |
1371 | { | |
1372 | int i; | |
1373 | printk(KERN_ERR "%03x:", offset); | |
b28a02de PE |
1374 | for (i = 0; i < limit; i++) { |
1375 | printk(" %02x", (unsigned char)data[offset + i]); | |
1da177e4 LT |
1376 | } |
1377 | printk("\n"); | |
1378 | } | |
1379 | #endif | |
1380 | ||
1381 | #if DEBUG | |
1382 | ||
343e0d7a | 1383 | static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines) |
1da177e4 LT |
1384 | { |
1385 | int i, size; | |
1386 | char *realobj; | |
1387 | ||
1388 | if (cachep->flags & SLAB_RED_ZONE) { | |
1389 | printk(KERN_ERR "Redzone: 0x%lx/0x%lx.\n", | |
b28a02de PE |
1390 | *dbg_redzone1(cachep, objp), |
1391 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
1392 | } |
1393 | ||
1394 | if (cachep->flags & SLAB_STORE_USER) { | |
1395 | printk(KERN_ERR "Last user: [<%p>]", | |
b28a02de | 1396 | *dbg_userword(cachep, objp)); |
1da177e4 | 1397 | print_symbol("(%s)", |
b28a02de | 1398 | (unsigned long)*dbg_userword(cachep, objp)); |
1da177e4 LT |
1399 | printk("\n"); |
1400 | } | |
3dafccf2 MS |
1401 | realobj = (char *)objp + obj_offset(cachep); |
1402 | size = obj_size(cachep); | |
b28a02de | 1403 | for (i = 0; i < size && lines; i += 16, lines--) { |
1da177e4 LT |
1404 | int limit; |
1405 | limit = 16; | |
b28a02de PE |
1406 | if (i + limit > size) |
1407 | limit = size - i; | |
1da177e4 LT |
1408 | dump_line(realobj, i, limit); |
1409 | } | |
1410 | } | |
1411 | ||
343e0d7a | 1412 | static void check_poison_obj(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
1413 | { |
1414 | char *realobj; | |
1415 | int size, i; | |
1416 | int lines = 0; | |
1417 | ||
3dafccf2 MS |
1418 | realobj = (char *)objp + obj_offset(cachep); |
1419 | size = obj_size(cachep); | |
1da177e4 | 1420 | |
b28a02de | 1421 | for (i = 0; i < size; i++) { |
1da177e4 | 1422 | char exp = POISON_FREE; |
b28a02de | 1423 | if (i == size - 1) |
1da177e4 LT |
1424 | exp = POISON_END; |
1425 | if (realobj[i] != exp) { | |
1426 | int limit; | |
1427 | /* Mismatch ! */ | |
1428 | /* Print header */ | |
1429 | if (lines == 0) { | |
b28a02de PE |
1430 | printk(KERN_ERR |
1431 | "Slab corruption: start=%p, len=%d\n", | |
1432 | realobj, size); | |
1da177e4 LT |
1433 | print_objinfo(cachep, objp, 0); |
1434 | } | |
1435 | /* Hexdump the affected line */ | |
b28a02de | 1436 | i = (i / 16) * 16; |
1da177e4 | 1437 | limit = 16; |
b28a02de PE |
1438 | if (i + limit > size) |
1439 | limit = size - i; | |
1da177e4 LT |
1440 | dump_line(realobj, i, limit); |
1441 | i += 16; | |
1442 | lines++; | |
1443 | /* Limit to 5 lines */ | |
1444 | if (lines > 5) | |
1445 | break; | |
1446 | } | |
1447 | } | |
1448 | if (lines != 0) { | |
1449 | /* Print some data about the neighboring objects, if they | |
1450 | * exist: | |
1451 | */ | |
6ed5eb22 | 1452 | struct slab *slabp = virt_to_slab(objp); |
1da177e4 LT |
1453 | int objnr; |
1454 | ||
3dafccf2 | 1455 | objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size; |
1da177e4 | 1456 | if (objnr) { |
3dafccf2 MS |
1457 | objp = slabp->s_mem + (objnr - 1) * cachep->buffer_size; |
1458 | realobj = (char *)objp + obj_offset(cachep); | |
1da177e4 | 1459 | printk(KERN_ERR "Prev obj: start=%p, len=%d\n", |
b28a02de | 1460 | realobj, size); |
1da177e4 LT |
1461 | print_objinfo(cachep, objp, 2); |
1462 | } | |
b28a02de | 1463 | if (objnr + 1 < cachep->num) { |
3dafccf2 MS |
1464 | objp = slabp->s_mem + (objnr + 1) * cachep->buffer_size; |
1465 | realobj = (char *)objp + obj_offset(cachep); | |
1da177e4 | 1466 | printk(KERN_ERR "Next obj: start=%p, len=%d\n", |
b28a02de | 1467 | realobj, size); |
1da177e4 LT |
1468 | print_objinfo(cachep, objp, 2); |
1469 | } | |
1470 | } | |
1471 | } | |
1472 | #endif | |
1473 | ||
12dd36fa MD |
1474 | #if DEBUG |
1475 | /** | |
1476 | * slab_destroy_objs - call the registered destructor for each object in | |
1477 | * a slab that is to be destroyed. | |
1da177e4 | 1478 | */ |
343e0d7a | 1479 | static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp) |
1da177e4 | 1480 | { |
1da177e4 LT |
1481 | int i; |
1482 | for (i = 0; i < cachep->num; i++) { | |
3dafccf2 | 1483 | void *objp = slabp->s_mem + cachep->buffer_size * i; |
1da177e4 LT |
1484 | |
1485 | if (cachep->flags & SLAB_POISON) { | |
1486 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
3dafccf2 | 1487 | if ((cachep->buffer_size % PAGE_SIZE) == 0 |
b28a02de PE |
1488 | && OFF_SLAB(cachep)) |
1489 | kernel_map_pages(virt_to_page(objp), | |
3dafccf2 | 1490 | cachep->buffer_size / PAGE_SIZE, |
b28a02de | 1491 | 1); |
1da177e4 LT |
1492 | else |
1493 | check_poison_obj(cachep, objp); | |
1494 | #else | |
1495 | check_poison_obj(cachep, objp); | |
1496 | #endif | |
1497 | } | |
1498 | if (cachep->flags & SLAB_RED_ZONE) { | |
1499 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) | |
1500 | slab_error(cachep, "start of a freed object " | |
b28a02de | 1501 | "was overwritten"); |
1da177e4 LT |
1502 | if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) |
1503 | slab_error(cachep, "end of a freed object " | |
b28a02de | 1504 | "was overwritten"); |
1da177e4 LT |
1505 | } |
1506 | if (cachep->dtor && !(cachep->flags & SLAB_POISON)) | |
3dafccf2 | 1507 | (cachep->dtor) (objp + obj_offset(cachep), cachep, 0); |
1da177e4 | 1508 | } |
12dd36fa | 1509 | } |
1da177e4 | 1510 | #else |
343e0d7a | 1511 | static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp) |
12dd36fa | 1512 | { |
1da177e4 LT |
1513 | if (cachep->dtor) { |
1514 | int i; | |
1515 | for (i = 0; i < cachep->num; i++) { | |
3dafccf2 | 1516 | void *objp = slabp->s_mem + cachep->buffer_size * i; |
b28a02de | 1517 | (cachep->dtor) (objp, cachep, 0); |
1da177e4 LT |
1518 | } |
1519 | } | |
12dd36fa | 1520 | } |
1da177e4 LT |
1521 | #endif |
1522 | ||
12dd36fa MD |
1523 | /** |
1524 | * Destroy all the objs in a slab, and release the mem back to the system. | |
1525 | * Before calling the slab must have been unlinked from the cache. | |
1526 | * The cache-lock is not held/needed. | |
1527 | */ | |
343e0d7a | 1528 | static void slab_destroy(struct kmem_cache *cachep, struct slab *slabp) |
12dd36fa MD |
1529 | { |
1530 | void *addr = slabp->s_mem - slabp->colouroff; | |
1531 | ||
1532 | slab_destroy_objs(cachep, slabp); | |
1da177e4 LT |
1533 | if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) { |
1534 | struct slab_rcu *slab_rcu; | |
1535 | ||
b28a02de | 1536 | slab_rcu = (struct slab_rcu *)slabp; |
1da177e4 LT |
1537 | slab_rcu->cachep = cachep; |
1538 | slab_rcu->addr = addr; | |
1539 | call_rcu(&slab_rcu->head, kmem_rcu_free); | |
1540 | } else { | |
1541 | kmem_freepages(cachep, addr); | |
1542 | if (OFF_SLAB(cachep)) | |
1543 | kmem_cache_free(cachep->slabp_cache, slabp); | |
1544 | } | |
1545 | } | |
1546 | ||
3dafccf2 | 1547 | /* For setting up all the kmem_list3s for cache whose buffer_size is same |
e498be7d | 1548 | as size of kmem_list3. */ |
343e0d7a | 1549 | static void set_up_list3s(struct kmem_cache *cachep, int index) |
e498be7d CL |
1550 | { |
1551 | int node; | |
1552 | ||
1553 | for_each_online_node(node) { | |
b28a02de | 1554 | cachep->nodelists[node] = &initkmem_list3[index + node]; |
e498be7d | 1555 | cachep->nodelists[node]->next_reap = jiffies + |
b28a02de PE |
1556 | REAPTIMEOUT_LIST3 + |
1557 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; | |
e498be7d CL |
1558 | } |
1559 | } | |
1560 | ||
4d268eba | 1561 | /** |
a70773dd RD |
1562 | * calculate_slab_order - calculate size (page order) of slabs |
1563 | * @cachep: pointer to the cache that is being created | |
1564 | * @size: size of objects to be created in this cache. | |
1565 | * @align: required alignment for the objects. | |
1566 | * @flags: slab allocation flags | |
1567 | * | |
1568 | * Also calculates the number of objects per slab. | |
4d268eba PE |
1569 | * |
1570 | * This could be made much more intelligent. For now, try to avoid using | |
1571 | * high order pages for slabs. When the gfp() functions are more friendly | |
1572 | * towards high-order requests, this should be changed. | |
1573 | */ | |
ee13d785 RD |
1574 | static inline size_t calculate_slab_order(struct kmem_cache *cachep, |
1575 | size_t size, size_t align, unsigned long flags) | |
4d268eba PE |
1576 | { |
1577 | size_t left_over = 0; | |
1578 | ||
b28a02de | 1579 | for (;; cachep->gfporder++) { |
4d268eba PE |
1580 | unsigned int num; |
1581 | size_t remainder; | |
1582 | ||
1583 | if (cachep->gfporder > MAX_GFP_ORDER) { | |
1584 | cachep->num = 0; | |
1585 | break; | |
1586 | } | |
1587 | ||
1588 | cache_estimate(cachep->gfporder, size, align, flags, | |
1589 | &remainder, &num); | |
1590 | if (!num) | |
1591 | continue; | |
1592 | /* More than offslab_limit objects will cause problems */ | |
1593 | if (flags & CFLGS_OFF_SLAB && cachep->num > offslab_limit) | |
1594 | break; | |
1595 | ||
1596 | cachep->num = num; | |
1597 | left_over = remainder; | |
1598 | ||
1599 | /* | |
1600 | * Large number of objects is good, but very large slabs are | |
1601 | * currently bad for the gfp()s. | |
1602 | */ | |
1603 | if (cachep->gfporder >= slab_break_gfp_order) | |
1604 | break; | |
1605 | ||
1606 | if ((left_over * 8) <= (PAGE_SIZE << cachep->gfporder)) | |
1607 | /* Acceptable internal fragmentation */ | |
1608 | break; | |
1609 | } | |
1610 | return left_over; | |
1611 | } | |
1612 | ||
1da177e4 LT |
1613 | /** |
1614 | * kmem_cache_create - Create a cache. | |
1615 | * @name: A string which is used in /proc/slabinfo to identify this cache. | |
1616 | * @size: The size of objects to be created in this cache. | |
1617 | * @align: The required alignment for the objects. | |
1618 | * @flags: SLAB flags | |
1619 | * @ctor: A constructor for the objects. | |
1620 | * @dtor: A destructor for the objects. | |
1621 | * | |
1622 | * Returns a ptr to the cache on success, NULL on failure. | |
1623 | * Cannot be called within a int, but can be interrupted. | |
1624 | * The @ctor is run when new pages are allocated by the cache | |
1625 | * and the @dtor is run before the pages are handed back. | |
1626 | * | |
1627 | * @name must be valid until the cache is destroyed. This implies that | |
1628 | * the module calling this has to destroy the cache before getting | |
1629 | * unloaded. | |
1630 | * | |
1631 | * The flags are | |
1632 | * | |
1633 | * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5) | |
1634 | * to catch references to uninitialised memory. | |
1635 | * | |
1636 | * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check | |
1637 | * for buffer overruns. | |
1638 | * | |
1639 | * %SLAB_NO_REAP - Don't automatically reap this cache when we're under | |
1640 | * memory pressure. | |
1641 | * | |
1642 | * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware | |
1643 | * cacheline. This can be beneficial if you're counting cycles as closely | |
1644 | * as davem. | |
1645 | */ | |
343e0d7a | 1646 | struct kmem_cache * |
1da177e4 | 1647 | kmem_cache_create (const char *name, size_t size, size_t align, |
343e0d7a PE |
1648 | unsigned long flags, void (*ctor)(void*, struct kmem_cache *, unsigned long), |
1649 | void (*dtor)(void*, struct kmem_cache *, unsigned long)) | |
1da177e4 LT |
1650 | { |
1651 | size_t left_over, slab_size, ralign; | |
343e0d7a | 1652 | struct kmem_cache *cachep = NULL; |
4f12bb4f | 1653 | struct list_head *p; |
1da177e4 LT |
1654 | |
1655 | /* | |
1656 | * Sanity checks... these are all serious usage bugs. | |
1657 | */ | |
1658 | if ((!name) || | |
b28a02de PE |
1659 | in_interrupt() || |
1660 | (size < BYTES_PER_WORD) || | |
1661 | (size > (1 << MAX_OBJ_ORDER) * PAGE_SIZE) || (dtor && !ctor)) { | |
1662 | printk(KERN_ERR "%s: Early error in slab %s\n", | |
1663 | __FUNCTION__, name); | |
1664 | BUG(); | |
1665 | } | |
1da177e4 | 1666 | |
fc0abb14 | 1667 | mutex_lock(&cache_chain_mutex); |
4f12bb4f AM |
1668 | |
1669 | list_for_each(p, &cache_chain) { | |
343e0d7a | 1670 | struct kmem_cache *pc = list_entry(p, struct kmem_cache, next); |
4f12bb4f AM |
1671 | mm_segment_t old_fs = get_fs(); |
1672 | char tmp; | |
1673 | int res; | |
1674 | ||
1675 | /* | |
1676 | * This happens when the module gets unloaded and doesn't | |
1677 | * destroy its slab cache and no-one else reuses the vmalloc | |
1678 | * area of the module. Print a warning. | |
1679 | */ | |
1680 | set_fs(KERNEL_DS); | |
1681 | res = __get_user(tmp, pc->name); | |
1682 | set_fs(old_fs); | |
1683 | if (res) { | |
1684 | printk("SLAB: cache with size %d has lost its name\n", | |
3dafccf2 | 1685 | pc->buffer_size); |
4f12bb4f AM |
1686 | continue; |
1687 | } | |
1688 | ||
b28a02de | 1689 | if (!strcmp(pc->name, name)) { |
4f12bb4f AM |
1690 | printk("kmem_cache_create: duplicate cache %s\n", name); |
1691 | dump_stack(); | |
1692 | goto oops; | |
1693 | } | |
1694 | } | |
1695 | ||
1da177e4 LT |
1696 | #if DEBUG |
1697 | WARN_ON(strchr(name, ' ')); /* It confuses parsers */ | |
1698 | if ((flags & SLAB_DEBUG_INITIAL) && !ctor) { | |
1699 | /* No constructor, but inital state check requested */ | |
1700 | printk(KERN_ERR "%s: No con, but init state check " | |
b28a02de | 1701 | "requested - %s\n", __FUNCTION__, name); |
1da177e4 LT |
1702 | flags &= ~SLAB_DEBUG_INITIAL; |
1703 | } | |
1da177e4 LT |
1704 | #if FORCED_DEBUG |
1705 | /* | |
1706 | * Enable redzoning and last user accounting, except for caches with | |
1707 | * large objects, if the increased size would increase the object size | |
1708 | * above the next power of two: caches with object sizes just above a | |
1709 | * power of two have a significant amount of internal fragmentation. | |
1710 | */ | |
b28a02de PE |
1711 | if ((size < 4096 |
1712 | || fls(size - 1) == fls(size - 1 + 3 * BYTES_PER_WORD))) | |
1713 | flags |= SLAB_RED_ZONE | SLAB_STORE_USER; | |
1da177e4 LT |
1714 | if (!(flags & SLAB_DESTROY_BY_RCU)) |
1715 | flags |= SLAB_POISON; | |
1716 | #endif | |
1717 | if (flags & SLAB_DESTROY_BY_RCU) | |
1718 | BUG_ON(flags & SLAB_POISON); | |
1719 | #endif | |
1720 | if (flags & SLAB_DESTROY_BY_RCU) | |
1721 | BUG_ON(dtor); | |
1722 | ||
1723 | /* | |
1724 | * Always checks flags, a caller might be expecting debug | |
1725 | * support which isn't available. | |
1726 | */ | |
1727 | if (flags & ~CREATE_MASK) | |
1728 | BUG(); | |
1729 | ||
1730 | /* Check that size is in terms of words. This is needed to avoid | |
1731 | * unaligned accesses for some archs when redzoning is used, and makes | |
1732 | * sure any on-slab bufctl's are also correctly aligned. | |
1733 | */ | |
b28a02de PE |
1734 | if (size & (BYTES_PER_WORD - 1)) { |
1735 | size += (BYTES_PER_WORD - 1); | |
1736 | size &= ~(BYTES_PER_WORD - 1); | |
1da177e4 LT |
1737 | } |
1738 | ||
1739 | /* calculate out the final buffer alignment: */ | |
1740 | /* 1) arch recommendation: can be overridden for debug */ | |
1741 | if (flags & SLAB_HWCACHE_ALIGN) { | |
1742 | /* Default alignment: as specified by the arch code. | |
1743 | * Except if an object is really small, then squeeze multiple | |
1744 | * objects into one cacheline. | |
1745 | */ | |
1746 | ralign = cache_line_size(); | |
b28a02de | 1747 | while (size <= ralign / 2) |
1da177e4 LT |
1748 | ralign /= 2; |
1749 | } else { | |
1750 | ralign = BYTES_PER_WORD; | |
1751 | } | |
1752 | /* 2) arch mandated alignment: disables debug if necessary */ | |
1753 | if (ralign < ARCH_SLAB_MINALIGN) { | |
1754 | ralign = ARCH_SLAB_MINALIGN; | |
1755 | if (ralign > BYTES_PER_WORD) | |
b28a02de | 1756 | flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
1da177e4 LT |
1757 | } |
1758 | /* 3) caller mandated alignment: disables debug if necessary */ | |
1759 | if (ralign < align) { | |
1760 | ralign = align; | |
1761 | if (ralign > BYTES_PER_WORD) | |
b28a02de | 1762 | flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
1da177e4 LT |
1763 | } |
1764 | /* 4) Store it. Note that the debug code below can reduce | |
1765 | * the alignment to BYTES_PER_WORD. | |
1766 | */ | |
1767 | align = ralign; | |
1768 | ||
1769 | /* Get cache's description obj. */ | |
343e0d7a | 1770 | cachep = kmem_cache_alloc(&cache_cache, SLAB_KERNEL); |
1da177e4 | 1771 | if (!cachep) |
4f12bb4f | 1772 | goto oops; |
343e0d7a | 1773 | memset(cachep, 0, sizeof(struct kmem_cache)); |
1da177e4 LT |
1774 | |
1775 | #if DEBUG | |
3dafccf2 | 1776 | cachep->obj_size = size; |
1da177e4 LT |
1777 | |
1778 | if (flags & SLAB_RED_ZONE) { | |
1779 | /* redzoning only works with word aligned caches */ | |
1780 | align = BYTES_PER_WORD; | |
1781 | ||
1782 | /* add space for red zone words */ | |
3dafccf2 | 1783 | cachep->obj_offset += BYTES_PER_WORD; |
b28a02de | 1784 | size += 2 * BYTES_PER_WORD; |
1da177e4 LT |
1785 | } |
1786 | if (flags & SLAB_STORE_USER) { | |
1787 | /* user store requires word alignment and | |
1788 | * one word storage behind the end of the real | |
1789 | * object. | |
1790 | */ | |
1791 | align = BYTES_PER_WORD; | |
1792 | size += BYTES_PER_WORD; | |
1793 | } | |
1794 | #if FORCED_DEBUG && defined(CONFIG_DEBUG_PAGEALLOC) | |
b28a02de | 1795 | if (size >= malloc_sizes[INDEX_L3 + 1].cs_size |
3dafccf2 MS |
1796 | && cachep->obj_size > cache_line_size() && size < PAGE_SIZE) { |
1797 | cachep->obj_offset += PAGE_SIZE - size; | |
1da177e4 LT |
1798 | size = PAGE_SIZE; |
1799 | } | |
1800 | #endif | |
1801 | #endif | |
1802 | ||
1803 | /* Determine if the slab management is 'on' or 'off' slab. */ | |
b28a02de | 1804 | if (size >= (PAGE_SIZE >> 3)) |
1da177e4 LT |
1805 | /* |
1806 | * Size is large, assume best to place the slab management obj | |
1807 | * off-slab (should allow better packing of objs). | |
1808 | */ | |
1809 | flags |= CFLGS_OFF_SLAB; | |
1810 | ||
1811 | size = ALIGN(size, align); | |
1812 | ||
1813 | if ((flags & SLAB_RECLAIM_ACCOUNT) && size <= PAGE_SIZE) { | |
1814 | /* | |
1815 | * A VFS-reclaimable slab tends to have most allocations | |
1816 | * as GFP_NOFS and we really don't want to have to be allocating | |
1817 | * higher-order pages when we are unable to shrink dcache. | |
1818 | */ | |
1819 | cachep->gfporder = 0; | |
1820 | cache_estimate(cachep->gfporder, size, align, flags, | |
b28a02de | 1821 | &left_over, &cachep->num); |
4d268eba PE |
1822 | } else |
1823 | left_over = calculate_slab_order(cachep, size, align, flags); | |
1da177e4 LT |
1824 | |
1825 | if (!cachep->num) { | |
1826 | printk("kmem_cache_create: couldn't create cache %s.\n", name); | |
1827 | kmem_cache_free(&cache_cache, cachep); | |
1828 | cachep = NULL; | |
4f12bb4f | 1829 | goto oops; |
1da177e4 | 1830 | } |
b28a02de PE |
1831 | slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t) |
1832 | + sizeof(struct slab), align); | |
1da177e4 LT |
1833 | |
1834 | /* | |
1835 | * If the slab has been placed off-slab, and we have enough space then | |
1836 | * move it on-slab. This is at the expense of any extra colouring. | |
1837 | */ | |
1838 | if (flags & CFLGS_OFF_SLAB && left_over >= slab_size) { | |
1839 | flags &= ~CFLGS_OFF_SLAB; | |
1840 | left_over -= slab_size; | |
1841 | } | |
1842 | ||
1843 | if (flags & CFLGS_OFF_SLAB) { | |
1844 | /* really off slab. No need for manual alignment */ | |
b28a02de PE |
1845 | slab_size = |
1846 | cachep->num * sizeof(kmem_bufctl_t) + sizeof(struct slab); | |
1da177e4 LT |
1847 | } |
1848 | ||
1849 | cachep->colour_off = cache_line_size(); | |
1850 | /* Offset must be a multiple of the alignment. */ | |
1851 | if (cachep->colour_off < align) | |
1852 | cachep->colour_off = align; | |
b28a02de | 1853 | cachep->colour = left_over / cachep->colour_off; |
1da177e4 LT |
1854 | cachep->slab_size = slab_size; |
1855 | cachep->flags = flags; | |
1856 | cachep->gfpflags = 0; | |
1857 | if (flags & SLAB_CACHE_DMA) | |
1858 | cachep->gfpflags |= GFP_DMA; | |
1859 | spin_lock_init(&cachep->spinlock); | |
3dafccf2 | 1860 | cachep->buffer_size = size; |
1da177e4 LT |
1861 | |
1862 | if (flags & CFLGS_OFF_SLAB) | |
b2d55073 | 1863 | cachep->slabp_cache = kmem_find_general_cachep(slab_size, 0u); |
1da177e4 LT |
1864 | cachep->ctor = ctor; |
1865 | cachep->dtor = dtor; | |
1866 | cachep->name = name; | |
1867 | ||
1868 | /* Don't let CPUs to come and go */ | |
1869 | lock_cpu_hotplug(); | |
1870 | ||
1871 | if (g_cpucache_up == FULL) { | |
1872 | enable_cpucache(cachep); | |
1873 | } else { | |
1874 | if (g_cpucache_up == NONE) { | |
1875 | /* Note: the first kmem_cache_create must create | |
1876 | * the cache that's used by kmalloc(24), otherwise | |
1877 | * the creation of further caches will BUG(). | |
1878 | */ | |
e498be7d | 1879 | cachep->array[smp_processor_id()] = |
b28a02de | 1880 | &initarray_generic.cache; |
e498be7d CL |
1881 | |
1882 | /* If the cache that's used by | |
1883 | * kmalloc(sizeof(kmem_list3)) is the first cache, | |
1884 | * then we need to set up all its list3s, otherwise | |
1885 | * the creation of further caches will BUG(). | |
1886 | */ | |
1887 | set_up_list3s(cachep, SIZE_AC); | |
1888 | if (INDEX_AC == INDEX_L3) | |
1889 | g_cpucache_up = PARTIAL_L3; | |
1890 | else | |
1891 | g_cpucache_up = PARTIAL_AC; | |
1da177e4 | 1892 | } else { |
e498be7d | 1893 | cachep->array[smp_processor_id()] = |
b28a02de | 1894 | kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d CL |
1895 | |
1896 | if (g_cpucache_up == PARTIAL_AC) { | |
1897 | set_up_list3s(cachep, SIZE_L3); | |
1898 | g_cpucache_up = PARTIAL_L3; | |
1899 | } else { | |
1900 | int node; | |
1901 | for_each_online_node(node) { | |
1902 | ||
1903 | cachep->nodelists[node] = | |
b28a02de PE |
1904 | kmalloc_node(sizeof |
1905 | (struct kmem_list3), | |
1906 | GFP_KERNEL, node); | |
e498be7d | 1907 | BUG_ON(!cachep->nodelists[node]); |
b28a02de PE |
1908 | kmem_list3_init(cachep-> |
1909 | nodelists[node]); | |
e498be7d CL |
1910 | } |
1911 | } | |
1da177e4 | 1912 | } |
e498be7d | 1913 | cachep->nodelists[numa_node_id()]->next_reap = |
b28a02de PE |
1914 | jiffies + REAPTIMEOUT_LIST3 + |
1915 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; | |
e498be7d | 1916 | |
9a2dba4b PE |
1917 | BUG_ON(!cpu_cache_get(cachep)); |
1918 | cpu_cache_get(cachep)->avail = 0; | |
1919 | cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES; | |
1920 | cpu_cache_get(cachep)->batchcount = 1; | |
1921 | cpu_cache_get(cachep)->touched = 0; | |
1da177e4 LT |
1922 | cachep->batchcount = 1; |
1923 | cachep->limit = BOOT_CPUCACHE_ENTRIES; | |
b28a02de | 1924 | } |
1da177e4 | 1925 | |
1da177e4 LT |
1926 | /* cache setup completed, link it into the list */ |
1927 | list_add(&cachep->next, &cache_chain); | |
1da177e4 | 1928 | unlock_cpu_hotplug(); |
b28a02de | 1929 | oops: |
1da177e4 LT |
1930 | if (!cachep && (flags & SLAB_PANIC)) |
1931 | panic("kmem_cache_create(): failed to create slab `%s'\n", | |
b28a02de | 1932 | name); |
fc0abb14 | 1933 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1934 | return cachep; |
1935 | } | |
1936 | EXPORT_SYMBOL(kmem_cache_create); | |
1937 | ||
1938 | #if DEBUG | |
1939 | static void check_irq_off(void) | |
1940 | { | |
1941 | BUG_ON(!irqs_disabled()); | |
1942 | } | |
1943 | ||
1944 | static void check_irq_on(void) | |
1945 | { | |
1946 | BUG_ON(irqs_disabled()); | |
1947 | } | |
1948 | ||
343e0d7a | 1949 | static void check_spinlock_acquired(struct kmem_cache *cachep) |
1da177e4 LT |
1950 | { |
1951 | #ifdef CONFIG_SMP | |
1952 | check_irq_off(); | |
e498be7d | 1953 | assert_spin_locked(&cachep->nodelists[numa_node_id()]->list_lock); |
1da177e4 LT |
1954 | #endif |
1955 | } | |
e498be7d | 1956 | |
343e0d7a | 1957 | static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) |
e498be7d CL |
1958 | { |
1959 | #ifdef CONFIG_SMP | |
1960 | check_irq_off(); | |
1961 | assert_spin_locked(&cachep->nodelists[node]->list_lock); | |
1962 | #endif | |
1963 | } | |
1964 | ||
1da177e4 LT |
1965 | #else |
1966 | #define check_irq_off() do { } while(0) | |
1967 | #define check_irq_on() do { } while(0) | |
1968 | #define check_spinlock_acquired(x) do { } while(0) | |
e498be7d | 1969 | #define check_spinlock_acquired_node(x, y) do { } while(0) |
1da177e4 LT |
1970 | #endif |
1971 | ||
1972 | /* | |
1973 | * Waits for all CPUs to execute func(). | |
1974 | */ | |
b28a02de | 1975 | static void smp_call_function_all_cpus(void (*func)(void *arg), void *arg) |
1da177e4 LT |
1976 | { |
1977 | check_irq_on(); | |
1978 | preempt_disable(); | |
1979 | ||
1980 | local_irq_disable(); | |
1981 | func(arg); | |
1982 | local_irq_enable(); | |
1983 | ||
1984 | if (smp_call_function(func, arg, 1, 1)) | |
1985 | BUG(); | |
1986 | ||
1987 | preempt_enable(); | |
1988 | } | |
1989 | ||
343e0d7a | 1990 | static void drain_array_locked(struct kmem_cache *cachep, struct array_cache *ac, |
b28a02de | 1991 | int force, int node); |
1da177e4 LT |
1992 | |
1993 | static void do_drain(void *arg) | |
1994 | { | |
343e0d7a | 1995 | struct kmem_cache *cachep = (struct kmem_cache *) arg; |
1da177e4 | 1996 | struct array_cache *ac; |
ff69416e | 1997 | int node = numa_node_id(); |
1da177e4 LT |
1998 | |
1999 | check_irq_off(); | |
9a2dba4b | 2000 | ac = cpu_cache_get(cachep); |
ff69416e CL |
2001 | spin_lock(&cachep->nodelists[node]->list_lock); |
2002 | free_block(cachep, ac->entry, ac->avail, node); | |
2003 | spin_unlock(&cachep->nodelists[node]->list_lock); | |
1da177e4 LT |
2004 | ac->avail = 0; |
2005 | } | |
2006 | ||
343e0d7a | 2007 | static void drain_cpu_caches(struct kmem_cache *cachep) |
1da177e4 | 2008 | { |
e498be7d CL |
2009 | struct kmem_list3 *l3; |
2010 | int node; | |
2011 | ||
1da177e4 LT |
2012 | smp_call_function_all_cpus(do_drain, cachep); |
2013 | check_irq_on(); | |
2014 | spin_lock_irq(&cachep->spinlock); | |
b28a02de | 2015 | for_each_online_node(node) { |
e498be7d CL |
2016 | l3 = cachep->nodelists[node]; |
2017 | if (l3) { | |
2018 | spin_lock(&l3->list_lock); | |
2019 | drain_array_locked(cachep, l3->shared, 1, node); | |
2020 | spin_unlock(&l3->list_lock); | |
2021 | if (l3->alien) | |
2022 | drain_alien_cache(cachep, l3); | |
2023 | } | |
2024 | } | |
1da177e4 LT |
2025 | spin_unlock_irq(&cachep->spinlock); |
2026 | } | |
2027 | ||
343e0d7a | 2028 | static int __node_shrink(struct kmem_cache *cachep, int node) |
1da177e4 LT |
2029 | { |
2030 | struct slab *slabp; | |
e498be7d | 2031 | struct kmem_list3 *l3 = cachep->nodelists[node]; |
1da177e4 LT |
2032 | int ret; |
2033 | ||
e498be7d | 2034 | for (;;) { |
1da177e4 LT |
2035 | struct list_head *p; |
2036 | ||
e498be7d CL |
2037 | p = l3->slabs_free.prev; |
2038 | if (p == &l3->slabs_free) | |
1da177e4 LT |
2039 | break; |
2040 | ||
e498be7d | 2041 | slabp = list_entry(l3->slabs_free.prev, struct slab, list); |
1da177e4 LT |
2042 | #if DEBUG |
2043 | if (slabp->inuse) | |
2044 | BUG(); | |
2045 | #endif | |
2046 | list_del(&slabp->list); | |
2047 | ||
e498be7d CL |
2048 | l3->free_objects -= cachep->num; |
2049 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 2050 | slab_destroy(cachep, slabp); |
e498be7d | 2051 | spin_lock_irq(&l3->list_lock); |
1da177e4 | 2052 | } |
b28a02de | 2053 | ret = !list_empty(&l3->slabs_full) || !list_empty(&l3->slabs_partial); |
1da177e4 LT |
2054 | return ret; |
2055 | } | |
2056 | ||
343e0d7a | 2057 | static int __cache_shrink(struct kmem_cache *cachep) |
e498be7d CL |
2058 | { |
2059 | int ret = 0, i = 0; | |
2060 | struct kmem_list3 *l3; | |
2061 | ||
2062 | drain_cpu_caches(cachep); | |
2063 | ||
2064 | check_irq_on(); | |
2065 | for_each_online_node(i) { | |
2066 | l3 = cachep->nodelists[i]; | |
2067 | if (l3) { | |
2068 | spin_lock_irq(&l3->list_lock); | |
2069 | ret += __node_shrink(cachep, i); | |
2070 | spin_unlock_irq(&l3->list_lock); | |
2071 | } | |
2072 | } | |
2073 | return (ret ? 1 : 0); | |
2074 | } | |
2075 | ||
1da177e4 LT |
2076 | /** |
2077 | * kmem_cache_shrink - Shrink a cache. | |
2078 | * @cachep: The cache to shrink. | |
2079 | * | |
2080 | * Releases as many slabs as possible for a cache. | |
2081 | * To help debugging, a zero exit status indicates all slabs were released. | |
2082 | */ | |
343e0d7a | 2083 | int kmem_cache_shrink(struct kmem_cache *cachep) |
1da177e4 LT |
2084 | { |
2085 | if (!cachep || in_interrupt()) | |
2086 | BUG(); | |
2087 | ||
2088 | return __cache_shrink(cachep); | |
2089 | } | |
2090 | EXPORT_SYMBOL(kmem_cache_shrink); | |
2091 | ||
2092 | /** | |
2093 | * kmem_cache_destroy - delete a cache | |
2094 | * @cachep: the cache to destroy | |
2095 | * | |
343e0d7a | 2096 | * Remove a struct kmem_cache object from the slab cache. |
1da177e4 LT |
2097 | * Returns 0 on success. |
2098 | * | |
2099 | * It is expected this function will be called by a module when it is | |
2100 | * unloaded. This will remove the cache completely, and avoid a duplicate | |
2101 | * cache being allocated each time a module is loaded and unloaded, if the | |
2102 | * module doesn't have persistent in-kernel storage across loads and unloads. | |
2103 | * | |
2104 | * The cache must be empty before calling this function. | |
2105 | * | |
2106 | * The caller must guarantee that noone will allocate memory from the cache | |
2107 | * during the kmem_cache_destroy(). | |
2108 | */ | |
343e0d7a | 2109 | int kmem_cache_destroy(struct kmem_cache *cachep) |
1da177e4 LT |
2110 | { |
2111 | int i; | |
e498be7d | 2112 | struct kmem_list3 *l3; |
1da177e4 LT |
2113 | |
2114 | if (!cachep || in_interrupt()) | |
2115 | BUG(); | |
2116 | ||
2117 | /* Don't let CPUs to come and go */ | |
2118 | lock_cpu_hotplug(); | |
2119 | ||
2120 | /* Find the cache in the chain of caches. */ | |
fc0abb14 | 2121 | mutex_lock(&cache_chain_mutex); |
1da177e4 LT |
2122 | /* |
2123 | * the chain is never empty, cache_cache is never destroyed | |
2124 | */ | |
2125 | list_del(&cachep->next); | |
fc0abb14 | 2126 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
2127 | |
2128 | if (__cache_shrink(cachep)) { | |
2129 | slab_error(cachep, "Can't free all objects"); | |
fc0abb14 | 2130 | mutex_lock(&cache_chain_mutex); |
b28a02de | 2131 | list_add(&cachep->next, &cache_chain); |
fc0abb14 | 2132 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
2133 | unlock_cpu_hotplug(); |
2134 | return 1; | |
2135 | } | |
2136 | ||
2137 | if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) | |
fbd568a3 | 2138 | synchronize_rcu(); |
1da177e4 | 2139 | |
e498be7d | 2140 | for_each_online_cpu(i) |
b28a02de | 2141 | kfree(cachep->array[i]); |
1da177e4 LT |
2142 | |
2143 | /* NUMA: free the list3 structures */ | |
e498be7d CL |
2144 | for_each_online_node(i) { |
2145 | if ((l3 = cachep->nodelists[i])) { | |
2146 | kfree(l3->shared); | |
2147 | free_alien_cache(l3->alien); | |
2148 | kfree(l3); | |
2149 | } | |
2150 | } | |
1da177e4 LT |
2151 | kmem_cache_free(&cache_cache, cachep); |
2152 | ||
2153 | unlock_cpu_hotplug(); | |
2154 | ||
2155 | return 0; | |
2156 | } | |
2157 | EXPORT_SYMBOL(kmem_cache_destroy); | |
2158 | ||
2159 | /* Get the memory for a slab management obj. */ | |
343e0d7a | 2160 | static struct slab *alloc_slabmgmt(struct kmem_cache *cachep, void *objp, |
b28a02de | 2161 | int colour_off, gfp_t local_flags) |
1da177e4 LT |
2162 | { |
2163 | struct slab *slabp; | |
b28a02de | 2164 | |
1da177e4 LT |
2165 | if (OFF_SLAB(cachep)) { |
2166 | /* Slab management obj is off-slab. */ | |
2167 | slabp = kmem_cache_alloc(cachep->slabp_cache, local_flags); | |
2168 | if (!slabp) | |
2169 | return NULL; | |
2170 | } else { | |
b28a02de | 2171 | slabp = objp + colour_off; |
1da177e4 LT |
2172 | colour_off += cachep->slab_size; |
2173 | } | |
2174 | slabp->inuse = 0; | |
2175 | slabp->colouroff = colour_off; | |
b28a02de | 2176 | slabp->s_mem = objp + colour_off; |
1da177e4 LT |
2177 | |
2178 | return slabp; | |
2179 | } | |
2180 | ||
2181 | static inline kmem_bufctl_t *slab_bufctl(struct slab *slabp) | |
2182 | { | |
b28a02de | 2183 | return (kmem_bufctl_t *) (slabp + 1); |
1da177e4 LT |
2184 | } |
2185 | ||
343e0d7a | 2186 | static void cache_init_objs(struct kmem_cache *cachep, |
b28a02de | 2187 | struct slab *slabp, unsigned long ctor_flags) |
1da177e4 LT |
2188 | { |
2189 | int i; | |
2190 | ||
2191 | for (i = 0; i < cachep->num; i++) { | |
3dafccf2 | 2192 | void *objp = slabp->s_mem + cachep->buffer_size * i; |
1da177e4 LT |
2193 | #if DEBUG |
2194 | /* need to poison the objs? */ | |
2195 | if (cachep->flags & SLAB_POISON) | |
2196 | poison_obj(cachep, objp, POISON_FREE); | |
2197 | if (cachep->flags & SLAB_STORE_USER) | |
2198 | *dbg_userword(cachep, objp) = NULL; | |
2199 | ||
2200 | if (cachep->flags & SLAB_RED_ZONE) { | |
2201 | *dbg_redzone1(cachep, objp) = RED_INACTIVE; | |
2202 | *dbg_redzone2(cachep, objp) = RED_INACTIVE; | |
2203 | } | |
2204 | /* | |
2205 | * Constructors are not allowed to allocate memory from | |
2206 | * the same cache which they are a constructor for. | |
2207 | * Otherwise, deadlock. They must also be threaded. | |
2208 | */ | |
2209 | if (cachep->ctor && !(cachep->flags & SLAB_POISON)) | |
3dafccf2 | 2210 | cachep->ctor(objp + obj_offset(cachep), cachep, |
b28a02de | 2211 | ctor_flags); |
1da177e4 LT |
2212 | |
2213 | if (cachep->flags & SLAB_RED_ZONE) { | |
2214 | if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) | |
2215 | slab_error(cachep, "constructor overwrote the" | |
b28a02de | 2216 | " end of an object"); |
1da177e4 LT |
2217 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) |
2218 | slab_error(cachep, "constructor overwrote the" | |
b28a02de | 2219 | " start of an object"); |
1da177e4 | 2220 | } |
3dafccf2 | 2221 | if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep) |
b28a02de PE |
2222 | && cachep->flags & SLAB_POISON) |
2223 | kernel_map_pages(virt_to_page(objp), | |
3dafccf2 | 2224 | cachep->buffer_size / PAGE_SIZE, 0); |
1da177e4 LT |
2225 | #else |
2226 | if (cachep->ctor) | |
2227 | cachep->ctor(objp, cachep, ctor_flags); | |
2228 | #endif | |
b28a02de | 2229 | slab_bufctl(slabp)[i] = i + 1; |
1da177e4 | 2230 | } |
b28a02de | 2231 | slab_bufctl(slabp)[i - 1] = BUFCTL_END; |
1da177e4 LT |
2232 | slabp->free = 0; |
2233 | } | |
2234 | ||
343e0d7a | 2235 | static void kmem_flagcheck(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 LT |
2236 | { |
2237 | if (flags & SLAB_DMA) { | |
2238 | if (!(cachep->gfpflags & GFP_DMA)) | |
2239 | BUG(); | |
2240 | } else { | |
2241 | if (cachep->gfpflags & GFP_DMA) | |
2242 | BUG(); | |
2243 | } | |
2244 | } | |
2245 | ||
343e0d7a | 2246 | static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp, int nodeid) |
78d382d7 MD |
2247 | { |
2248 | void *objp = slabp->s_mem + (slabp->free * cachep->buffer_size); | |
2249 | kmem_bufctl_t next; | |
2250 | ||
2251 | slabp->inuse++; | |
2252 | next = slab_bufctl(slabp)[slabp->free]; | |
2253 | #if DEBUG | |
2254 | slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE; | |
2255 | WARN_ON(slabp->nodeid != nodeid); | |
2256 | #endif | |
2257 | slabp->free = next; | |
2258 | ||
2259 | return objp; | |
2260 | } | |
2261 | ||
343e0d7a | 2262 | static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp, void *objp, |
78d382d7 MD |
2263 | int nodeid) |
2264 | { | |
2265 | unsigned int objnr = (unsigned)(objp-slabp->s_mem) / cachep->buffer_size; | |
2266 | ||
2267 | #if DEBUG | |
2268 | /* Verify that the slab belongs to the intended node */ | |
2269 | WARN_ON(slabp->nodeid != nodeid); | |
2270 | ||
2271 | if (slab_bufctl(slabp)[objnr] != BUFCTL_FREE) { | |
2272 | printk(KERN_ERR "slab: double free detected in cache " | |
2273 | "'%s', objp %p\n", cachep->name, objp); | |
2274 | BUG(); | |
2275 | } | |
2276 | #endif | |
2277 | slab_bufctl(slabp)[objnr] = slabp->free; | |
2278 | slabp->free = objnr; | |
2279 | slabp->inuse--; | |
2280 | } | |
2281 | ||
343e0d7a | 2282 | static void set_slab_attr(struct kmem_cache *cachep, struct slab *slabp, void *objp) |
1da177e4 LT |
2283 | { |
2284 | int i; | |
2285 | struct page *page; | |
2286 | ||
2287 | /* Nasty!!!!!! I hope this is OK. */ | |
2288 | i = 1 << cachep->gfporder; | |
2289 | page = virt_to_page(objp); | |
2290 | do { | |
065d41cb PE |
2291 | page_set_cache(page, cachep); |
2292 | page_set_slab(page, slabp); | |
1da177e4 LT |
2293 | page++; |
2294 | } while (--i); | |
2295 | } | |
2296 | ||
2297 | /* | |
2298 | * Grow (by 1) the number of slabs within a cache. This is called by | |
2299 | * kmem_cache_alloc() when there are no active objs left in a cache. | |
2300 | */ | |
343e0d7a | 2301 | static int cache_grow(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 | 2302 | { |
b28a02de PE |
2303 | struct slab *slabp; |
2304 | void *objp; | |
2305 | size_t offset; | |
2306 | gfp_t local_flags; | |
2307 | unsigned long ctor_flags; | |
e498be7d | 2308 | struct kmem_list3 *l3; |
1da177e4 LT |
2309 | |
2310 | /* Be lazy and only check for valid flags here, | |
b28a02de | 2311 | * keeping it out of the critical path in kmem_cache_alloc(). |
1da177e4 | 2312 | */ |
b28a02de | 2313 | if (flags & ~(SLAB_DMA | SLAB_LEVEL_MASK | SLAB_NO_GROW)) |
1da177e4 LT |
2314 | BUG(); |
2315 | if (flags & SLAB_NO_GROW) | |
2316 | return 0; | |
2317 | ||
2318 | ctor_flags = SLAB_CTOR_CONSTRUCTOR; | |
2319 | local_flags = (flags & SLAB_LEVEL_MASK); | |
2320 | if (!(local_flags & __GFP_WAIT)) | |
2321 | /* | |
2322 | * Not allowed to sleep. Need to tell a constructor about | |
2323 | * this - it might need to know... | |
2324 | */ | |
2325 | ctor_flags |= SLAB_CTOR_ATOMIC; | |
2326 | ||
2e1217cf | 2327 | /* Take the l3 list lock to change the colour_next on this node */ |
1da177e4 | 2328 | check_irq_off(); |
2e1217cf RT |
2329 | l3 = cachep->nodelists[nodeid]; |
2330 | spin_lock(&l3->list_lock); | |
1da177e4 LT |
2331 | |
2332 | /* Get colour for the slab, and cal the next value. */ | |
2e1217cf RT |
2333 | offset = l3->colour_next; |
2334 | l3->colour_next++; | |
2335 | if (l3->colour_next >= cachep->colour) | |
2336 | l3->colour_next = 0; | |
2337 | spin_unlock(&l3->list_lock); | |
1da177e4 | 2338 | |
2e1217cf | 2339 | offset *= cachep->colour_off; |
1da177e4 | 2340 | |
e498be7d | 2341 | check_irq_off(); |
1da177e4 LT |
2342 | if (local_flags & __GFP_WAIT) |
2343 | local_irq_enable(); | |
2344 | ||
2345 | /* | |
2346 | * The test for missing atomic flag is performed here, rather than | |
2347 | * the more obvious place, simply to reduce the critical path length | |
2348 | * in kmem_cache_alloc(). If a caller is seriously mis-behaving they | |
2349 | * will eventually be caught here (where it matters). | |
2350 | */ | |
2351 | kmem_flagcheck(cachep, flags); | |
2352 | ||
e498be7d CL |
2353 | /* Get mem for the objs. |
2354 | * Attempt to allocate a physical page from 'nodeid', | |
2355 | */ | |
1da177e4 LT |
2356 | if (!(objp = kmem_getpages(cachep, flags, nodeid))) |
2357 | goto failed; | |
2358 | ||
2359 | /* Get slab management. */ | |
2360 | if (!(slabp = alloc_slabmgmt(cachep, objp, offset, local_flags))) | |
2361 | goto opps1; | |
2362 | ||
e498be7d | 2363 | slabp->nodeid = nodeid; |
1da177e4 LT |
2364 | set_slab_attr(cachep, slabp, objp); |
2365 | ||
2366 | cache_init_objs(cachep, slabp, ctor_flags); | |
2367 | ||
2368 | if (local_flags & __GFP_WAIT) | |
2369 | local_irq_disable(); | |
2370 | check_irq_off(); | |
e498be7d | 2371 | spin_lock(&l3->list_lock); |
1da177e4 LT |
2372 | |
2373 | /* Make slab active. */ | |
e498be7d | 2374 | list_add_tail(&slabp->list, &(l3->slabs_free)); |
1da177e4 | 2375 | STATS_INC_GROWN(cachep); |
e498be7d CL |
2376 | l3->free_objects += cachep->num; |
2377 | spin_unlock(&l3->list_lock); | |
1da177e4 | 2378 | return 1; |
b28a02de | 2379 | opps1: |
1da177e4 | 2380 | kmem_freepages(cachep, objp); |
b28a02de | 2381 | failed: |
1da177e4 LT |
2382 | if (local_flags & __GFP_WAIT) |
2383 | local_irq_disable(); | |
2384 | return 0; | |
2385 | } | |
2386 | ||
2387 | #if DEBUG | |
2388 | ||
2389 | /* | |
2390 | * Perform extra freeing checks: | |
2391 | * - detect bad pointers. | |
2392 | * - POISON/RED_ZONE checking | |
2393 | * - destructor calls, for caches with POISON+dtor | |
2394 | */ | |
2395 | static void kfree_debugcheck(const void *objp) | |
2396 | { | |
2397 | struct page *page; | |
2398 | ||
2399 | if (!virt_addr_valid(objp)) { | |
2400 | printk(KERN_ERR "kfree_debugcheck: out of range ptr %lxh.\n", | |
b28a02de PE |
2401 | (unsigned long)objp); |
2402 | BUG(); | |
1da177e4 LT |
2403 | } |
2404 | page = virt_to_page(objp); | |
2405 | if (!PageSlab(page)) { | |
b28a02de PE |
2406 | printk(KERN_ERR "kfree_debugcheck: bad ptr %lxh.\n", |
2407 | (unsigned long)objp); | |
1da177e4 LT |
2408 | BUG(); |
2409 | } | |
2410 | } | |
2411 | ||
343e0d7a | 2412 | static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp, |
b28a02de | 2413 | void *caller) |
1da177e4 LT |
2414 | { |
2415 | struct page *page; | |
2416 | unsigned int objnr; | |
2417 | struct slab *slabp; | |
2418 | ||
3dafccf2 | 2419 | objp -= obj_offset(cachep); |
1da177e4 LT |
2420 | kfree_debugcheck(objp); |
2421 | page = virt_to_page(objp); | |
2422 | ||
065d41cb | 2423 | if (page_get_cache(page) != cachep) { |
b28a02de PE |
2424 | printk(KERN_ERR |
2425 | "mismatch in kmem_cache_free: expected cache %p, got %p\n", | |
2426 | page_get_cache(page), cachep); | |
1da177e4 | 2427 | printk(KERN_ERR "%p is %s.\n", cachep, cachep->name); |
b28a02de PE |
2428 | printk(KERN_ERR "%p is %s.\n", page_get_cache(page), |
2429 | page_get_cache(page)->name); | |
1da177e4 LT |
2430 | WARN_ON(1); |
2431 | } | |
065d41cb | 2432 | slabp = page_get_slab(page); |
1da177e4 LT |
2433 | |
2434 | if (cachep->flags & SLAB_RED_ZONE) { | |
b28a02de PE |
2435 | if (*dbg_redzone1(cachep, objp) != RED_ACTIVE |
2436 | || *dbg_redzone2(cachep, objp) != RED_ACTIVE) { | |
2437 | slab_error(cachep, | |
2438 | "double free, or memory outside" | |
2439 | " object was overwritten"); | |
2440 | printk(KERN_ERR | |
2441 | "%p: redzone 1: 0x%lx, redzone 2: 0x%lx.\n", | |
2442 | objp, *dbg_redzone1(cachep, objp), | |
2443 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
2444 | } |
2445 | *dbg_redzone1(cachep, objp) = RED_INACTIVE; | |
2446 | *dbg_redzone2(cachep, objp) = RED_INACTIVE; | |
2447 | } | |
2448 | if (cachep->flags & SLAB_STORE_USER) | |
2449 | *dbg_userword(cachep, objp) = caller; | |
2450 | ||
3dafccf2 | 2451 | objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size; |
1da177e4 LT |
2452 | |
2453 | BUG_ON(objnr >= cachep->num); | |
3dafccf2 | 2454 | BUG_ON(objp != slabp->s_mem + objnr * cachep->buffer_size); |
1da177e4 LT |
2455 | |
2456 | if (cachep->flags & SLAB_DEBUG_INITIAL) { | |
2457 | /* Need to call the slab's constructor so the | |
2458 | * caller can perform a verify of its state (debugging). | |
2459 | * Called without the cache-lock held. | |
2460 | */ | |
3dafccf2 | 2461 | cachep->ctor(objp + obj_offset(cachep), |
b28a02de | 2462 | cachep, SLAB_CTOR_CONSTRUCTOR | SLAB_CTOR_VERIFY); |
1da177e4 LT |
2463 | } |
2464 | if (cachep->flags & SLAB_POISON && cachep->dtor) { | |
2465 | /* we want to cache poison the object, | |
2466 | * call the destruction callback | |
2467 | */ | |
3dafccf2 | 2468 | cachep->dtor(objp + obj_offset(cachep), cachep, 0); |
1da177e4 LT |
2469 | } |
2470 | if (cachep->flags & SLAB_POISON) { | |
2471 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
3dafccf2 | 2472 | if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) { |
1da177e4 | 2473 | store_stackinfo(cachep, objp, (unsigned long)caller); |
b28a02de | 2474 | kernel_map_pages(virt_to_page(objp), |
3dafccf2 | 2475 | cachep->buffer_size / PAGE_SIZE, 0); |
1da177e4 LT |
2476 | } else { |
2477 | poison_obj(cachep, objp, POISON_FREE); | |
2478 | } | |
2479 | #else | |
2480 | poison_obj(cachep, objp, POISON_FREE); | |
2481 | #endif | |
2482 | } | |
2483 | return objp; | |
2484 | } | |
2485 | ||
343e0d7a | 2486 | static void check_slabp(struct kmem_cache *cachep, struct slab *slabp) |
1da177e4 LT |
2487 | { |
2488 | kmem_bufctl_t i; | |
2489 | int entries = 0; | |
b28a02de | 2490 | |
1da177e4 LT |
2491 | /* Check slab's freelist to see if this obj is there. */ |
2492 | for (i = slabp->free; i != BUFCTL_END; i = slab_bufctl(slabp)[i]) { | |
2493 | entries++; | |
2494 | if (entries > cachep->num || i >= cachep->num) | |
2495 | goto bad; | |
2496 | } | |
2497 | if (entries != cachep->num - slabp->inuse) { | |
b28a02de PE |
2498 | bad: |
2499 | printk(KERN_ERR | |
2500 | "slab: Internal list corruption detected in cache '%s'(%d), slabp %p(%d). Hexdump:\n", | |
2501 | cachep->name, cachep->num, slabp, slabp->inuse); | |
2502 | for (i = 0; | |
2503 | i < sizeof(slabp) + cachep->num * sizeof(kmem_bufctl_t); | |
2504 | i++) { | |
2505 | if ((i % 16) == 0) | |
1da177e4 | 2506 | printk("\n%03x:", i); |
b28a02de | 2507 | printk(" %02x", ((unsigned char *)slabp)[i]); |
1da177e4 LT |
2508 | } |
2509 | printk("\n"); | |
2510 | BUG(); | |
2511 | } | |
2512 | } | |
2513 | #else | |
2514 | #define kfree_debugcheck(x) do { } while(0) | |
2515 | #define cache_free_debugcheck(x,objp,z) (objp) | |
2516 | #define check_slabp(x,y) do { } while(0) | |
2517 | #endif | |
2518 | ||
343e0d7a | 2519 | static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 LT |
2520 | { |
2521 | int batchcount; | |
2522 | struct kmem_list3 *l3; | |
2523 | struct array_cache *ac; | |
2524 | ||
2525 | check_irq_off(); | |
9a2dba4b | 2526 | ac = cpu_cache_get(cachep); |
b28a02de | 2527 | retry: |
1da177e4 LT |
2528 | batchcount = ac->batchcount; |
2529 | if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { | |
2530 | /* if there was little recent activity on this | |
2531 | * cache, then perform only a partial refill. | |
2532 | * Otherwise we could generate refill bouncing. | |
2533 | */ | |
2534 | batchcount = BATCHREFILL_LIMIT; | |
2535 | } | |
e498be7d CL |
2536 | l3 = cachep->nodelists[numa_node_id()]; |
2537 | ||
2538 | BUG_ON(ac->avail > 0 || !l3); | |
2539 | spin_lock(&l3->list_lock); | |
1da177e4 | 2540 | |
1da177e4 LT |
2541 | if (l3->shared) { |
2542 | struct array_cache *shared_array = l3->shared; | |
2543 | if (shared_array->avail) { | |
2544 | if (batchcount > shared_array->avail) | |
2545 | batchcount = shared_array->avail; | |
2546 | shared_array->avail -= batchcount; | |
2547 | ac->avail = batchcount; | |
e498be7d | 2548 | memcpy(ac->entry, |
b28a02de PE |
2549 | &(shared_array->entry[shared_array->avail]), |
2550 | sizeof(void *) * batchcount); | |
1da177e4 LT |
2551 | shared_array->touched = 1; |
2552 | goto alloc_done; | |
2553 | } | |
2554 | } | |
2555 | while (batchcount > 0) { | |
2556 | struct list_head *entry; | |
2557 | struct slab *slabp; | |
2558 | /* Get slab alloc is to come from. */ | |
2559 | entry = l3->slabs_partial.next; | |
2560 | if (entry == &l3->slabs_partial) { | |
2561 | l3->free_touched = 1; | |
2562 | entry = l3->slabs_free.next; | |
2563 | if (entry == &l3->slabs_free) | |
2564 | goto must_grow; | |
2565 | } | |
2566 | ||
2567 | slabp = list_entry(entry, struct slab, list); | |
2568 | check_slabp(cachep, slabp); | |
2569 | check_spinlock_acquired(cachep); | |
2570 | while (slabp->inuse < cachep->num && batchcount--) { | |
1da177e4 LT |
2571 | STATS_INC_ALLOCED(cachep); |
2572 | STATS_INC_ACTIVE(cachep); | |
2573 | STATS_SET_HIGH(cachep); | |
2574 | ||
78d382d7 MD |
2575 | ac->entry[ac->avail++] = slab_get_obj(cachep, slabp, |
2576 | numa_node_id()); | |
1da177e4 LT |
2577 | } |
2578 | check_slabp(cachep, slabp); | |
2579 | ||
2580 | /* move slabp to correct slabp list: */ | |
2581 | list_del(&slabp->list); | |
2582 | if (slabp->free == BUFCTL_END) | |
2583 | list_add(&slabp->list, &l3->slabs_full); | |
2584 | else | |
2585 | list_add(&slabp->list, &l3->slabs_partial); | |
2586 | } | |
2587 | ||
b28a02de | 2588 | must_grow: |
1da177e4 | 2589 | l3->free_objects -= ac->avail; |
b28a02de | 2590 | alloc_done: |
e498be7d | 2591 | spin_unlock(&l3->list_lock); |
1da177e4 LT |
2592 | |
2593 | if (unlikely(!ac->avail)) { | |
2594 | int x; | |
e498be7d CL |
2595 | x = cache_grow(cachep, flags, numa_node_id()); |
2596 | ||
1da177e4 | 2597 | // cache_grow can reenable interrupts, then ac could change. |
9a2dba4b | 2598 | ac = cpu_cache_get(cachep); |
1da177e4 LT |
2599 | if (!x && ac->avail == 0) // no objects in sight? abort |
2600 | return NULL; | |
2601 | ||
b28a02de | 2602 | if (!ac->avail) // objects refilled by interrupt? |
1da177e4 LT |
2603 | goto retry; |
2604 | } | |
2605 | ac->touched = 1; | |
e498be7d | 2606 | return ac->entry[--ac->avail]; |
1da177e4 LT |
2607 | } |
2608 | ||
2609 | static inline void | |
343e0d7a | 2610 | cache_alloc_debugcheck_before(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 LT |
2611 | { |
2612 | might_sleep_if(flags & __GFP_WAIT); | |
2613 | #if DEBUG | |
2614 | kmem_flagcheck(cachep, flags); | |
2615 | #endif | |
2616 | } | |
2617 | ||
2618 | #if DEBUG | |
343e0d7a | 2619 | static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, gfp_t flags, |
b28a02de | 2620 | void *objp, void *caller) |
1da177e4 | 2621 | { |
b28a02de | 2622 | if (!objp) |
1da177e4 | 2623 | return objp; |
b28a02de | 2624 | if (cachep->flags & SLAB_POISON) { |
1da177e4 | 2625 | #ifdef CONFIG_DEBUG_PAGEALLOC |
3dafccf2 | 2626 | if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) |
b28a02de | 2627 | kernel_map_pages(virt_to_page(objp), |
3dafccf2 | 2628 | cachep->buffer_size / PAGE_SIZE, 1); |
1da177e4 LT |
2629 | else |
2630 | check_poison_obj(cachep, objp); | |
2631 | #else | |
2632 | check_poison_obj(cachep, objp); | |
2633 | #endif | |
2634 | poison_obj(cachep, objp, POISON_INUSE); | |
2635 | } | |
2636 | if (cachep->flags & SLAB_STORE_USER) | |
2637 | *dbg_userword(cachep, objp) = caller; | |
2638 | ||
2639 | if (cachep->flags & SLAB_RED_ZONE) { | |
b28a02de PE |
2640 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE |
2641 | || *dbg_redzone2(cachep, objp) != RED_INACTIVE) { | |
2642 | slab_error(cachep, | |
2643 | "double free, or memory outside" | |
2644 | " object was overwritten"); | |
2645 | printk(KERN_ERR | |
2646 | "%p: redzone 1: 0x%lx, redzone 2: 0x%lx.\n", | |
2647 | objp, *dbg_redzone1(cachep, objp), | |
2648 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
2649 | } |
2650 | *dbg_redzone1(cachep, objp) = RED_ACTIVE; | |
2651 | *dbg_redzone2(cachep, objp) = RED_ACTIVE; | |
2652 | } | |
3dafccf2 | 2653 | objp += obj_offset(cachep); |
1da177e4 | 2654 | if (cachep->ctor && cachep->flags & SLAB_POISON) { |
b28a02de | 2655 | unsigned long ctor_flags = SLAB_CTOR_CONSTRUCTOR; |
1da177e4 LT |
2656 | |
2657 | if (!(flags & __GFP_WAIT)) | |
2658 | ctor_flags |= SLAB_CTOR_ATOMIC; | |
2659 | ||
2660 | cachep->ctor(objp, cachep, ctor_flags); | |
b28a02de | 2661 | } |
1da177e4 LT |
2662 | return objp; |
2663 | } | |
2664 | #else | |
2665 | #define cache_alloc_debugcheck_after(a,b,objp,d) (objp) | |
2666 | #endif | |
2667 | ||
343e0d7a | 2668 | static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 | 2669 | { |
b28a02de | 2670 | void *objp; |
1da177e4 LT |
2671 | struct array_cache *ac; |
2672 | ||
dc85da15 | 2673 | #ifdef CONFIG_NUMA |
86c562a9 | 2674 | if (unlikely(current->mempolicy && !in_interrupt())) { |
dc85da15 CL |
2675 | int nid = slab_node(current->mempolicy); |
2676 | ||
2677 | if (nid != numa_node_id()) | |
2678 | return __cache_alloc_node(cachep, flags, nid); | |
2679 | } | |
2680 | #endif | |
2681 | ||
5c382300 | 2682 | check_irq_off(); |
9a2dba4b | 2683 | ac = cpu_cache_get(cachep); |
1da177e4 LT |
2684 | if (likely(ac->avail)) { |
2685 | STATS_INC_ALLOCHIT(cachep); | |
2686 | ac->touched = 1; | |
e498be7d | 2687 | objp = ac->entry[--ac->avail]; |
1da177e4 LT |
2688 | } else { |
2689 | STATS_INC_ALLOCMISS(cachep); | |
2690 | objp = cache_alloc_refill(cachep, flags); | |
2691 | } | |
5c382300 AK |
2692 | return objp; |
2693 | } | |
2694 | ||
7fd6b141 PE |
2695 | static __always_inline void * |
2696 | __cache_alloc(struct kmem_cache *cachep, gfp_t flags, void *caller) | |
5c382300 AK |
2697 | { |
2698 | unsigned long save_flags; | |
b28a02de | 2699 | void *objp; |
5c382300 AK |
2700 | |
2701 | cache_alloc_debugcheck_before(cachep, flags); | |
2702 | ||
2703 | local_irq_save(save_flags); | |
2704 | objp = ____cache_alloc(cachep, flags); | |
1da177e4 | 2705 | local_irq_restore(save_flags); |
34342e86 | 2706 | objp = cache_alloc_debugcheck_after(cachep, flags, objp, |
7fd6b141 | 2707 | caller); |
34342e86 | 2708 | prefetchw(objp); |
1da177e4 LT |
2709 | return objp; |
2710 | } | |
2711 | ||
e498be7d CL |
2712 | #ifdef CONFIG_NUMA |
2713 | /* | |
2714 | * A interface to enable slab creation on nodeid | |
1da177e4 | 2715 | */ |
343e0d7a | 2716 | static void *__cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
e498be7d CL |
2717 | { |
2718 | struct list_head *entry; | |
b28a02de PE |
2719 | struct slab *slabp; |
2720 | struct kmem_list3 *l3; | |
2721 | void *obj; | |
b28a02de PE |
2722 | int x; |
2723 | ||
2724 | l3 = cachep->nodelists[nodeid]; | |
2725 | BUG_ON(!l3); | |
2726 | ||
2727 | retry: | |
2728 | spin_lock(&l3->list_lock); | |
2729 | entry = l3->slabs_partial.next; | |
2730 | if (entry == &l3->slabs_partial) { | |
2731 | l3->free_touched = 1; | |
2732 | entry = l3->slabs_free.next; | |
2733 | if (entry == &l3->slabs_free) | |
2734 | goto must_grow; | |
2735 | } | |
2736 | ||
2737 | slabp = list_entry(entry, struct slab, list); | |
2738 | check_spinlock_acquired_node(cachep, nodeid); | |
2739 | check_slabp(cachep, slabp); | |
2740 | ||
2741 | STATS_INC_NODEALLOCS(cachep); | |
2742 | STATS_INC_ACTIVE(cachep); | |
2743 | STATS_SET_HIGH(cachep); | |
2744 | ||
2745 | BUG_ON(slabp->inuse == cachep->num); | |
2746 | ||
78d382d7 | 2747 | obj = slab_get_obj(cachep, slabp, nodeid); |
b28a02de PE |
2748 | check_slabp(cachep, slabp); |
2749 | l3->free_objects--; | |
2750 | /* move slabp to correct slabp list: */ | |
2751 | list_del(&slabp->list); | |
2752 | ||
2753 | if (slabp->free == BUFCTL_END) { | |
2754 | list_add(&slabp->list, &l3->slabs_full); | |
2755 | } else { | |
2756 | list_add(&slabp->list, &l3->slabs_partial); | |
2757 | } | |
e498be7d | 2758 | |
b28a02de PE |
2759 | spin_unlock(&l3->list_lock); |
2760 | goto done; | |
e498be7d | 2761 | |
b28a02de PE |
2762 | must_grow: |
2763 | spin_unlock(&l3->list_lock); | |
2764 | x = cache_grow(cachep, flags, nodeid); | |
1da177e4 | 2765 | |
b28a02de PE |
2766 | if (!x) |
2767 | return NULL; | |
e498be7d | 2768 | |
b28a02de PE |
2769 | goto retry; |
2770 | done: | |
2771 | return obj; | |
e498be7d CL |
2772 | } |
2773 | #endif | |
2774 | ||
2775 | /* | |
2776 | * Caller needs to acquire correct kmem_list's list_lock | |
2777 | */ | |
343e0d7a | 2778 | static void free_block(struct kmem_cache *cachep, void **objpp, int nr_objects, |
b28a02de | 2779 | int node) |
1da177e4 LT |
2780 | { |
2781 | int i; | |
e498be7d | 2782 | struct kmem_list3 *l3; |
1da177e4 LT |
2783 | |
2784 | for (i = 0; i < nr_objects; i++) { | |
2785 | void *objp = objpp[i]; | |
2786 | struct slab *slabp; | |
1da177e4 | 2787 | |
6ed5eb22 | 2788 | slabp = virt_to_slab(objp); |
ff69416e | 2789 | l3 = cachep->nodelists[node]; |
1da177e4 | 2790 | list_del(&slabp->list); |
ff69416e | 2791 | check_spinlock_acquired_node(cachep, node); |
1da177e4 | 2792 | check_slabp(cachep, slabp); |
78d382d7 | 2793 | slab_put_obj(cachep, slabp, objp, node); |
1da177e4 | 2794 | STATS_DEC_ACTIVE(cachep); |
e498be7d | 2795 | l3->free_objects++; |
1da177e4 LT |
2796 | check_slabp(cachep, slabp); |
2797 | ||
2798 | /* fixup slab chains */ | |
2799 | if (slabp->inuse == 0) { | |
e498be7d CL |
2800 | if (l3->free_objects > l3->free_limit) { |
2801 | l3->free_objects -= cachep->num; | |
1da177e4 LT |
2802 | slab_destroy(cachep, slabp); |
2803 | } else { | |
e498be7d | 2804 | list_add(&slabp->list, &l3->slabs_free); |
1da177e4 LT |
2805 | } |
2806 | } else { | |
2807 | /* Unconditionally move a slab to the end of the | |
2808 | * partial list on free - maximum time for the | |
2809 | * other objects to be freed, too. | |
2810 | */ | |
e498be7d | 2811 | list_add_tail(&slabp->list, &l3->slabs_partial); |
1da177e4 LT |
2812 | } |
2813 | } | |
2814 | } | |
2815 | ||
343e0d7a | 2816 | static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) |
1da177e4 LT |
2817 | { |
2818 | int batchcount; | |
e498be7d | 2819 | struct kmem_list3 *l3; |
ff69416e | 2820 | int node = numa_node_id(); |
1da177e4 LT |
2821 | |
2822 | batchcount = ac->batchcount; | |
2823 | #if DEBUG | |
2824 | BUG_ON(!batchcount || batchcount > ac->avail); | |
2825 | #endif | |
2826 | check_irq_off(); | |
ff69416e | 2827 | l3 = cachep->nodelists[node]; |
e498be7d CL |
2828 | spin_lock(&l3->list_lock); |
2829 | if (l3->shared) { | |
2830 | struct array_cache *shared_array = l3->shared; | |
b28a02de | 2831 | int max = shared_array->limit - shared_array->avail; |
1da177e4 LT |
2832 | if (max) { |
2833 | if (batchcount > max) | |
2834 | batchcount = max; | |
e498be7d | 2835 | memcpy(&(shared_array->entry[shared_array->avail]), |
b28a02de | 2836 | ac->entry, sizeof(void *) * batchcount); |
1da177e4 LT |
2837 | shared_array->avail += batchcount; |
2838 | goto free_done; | |
2839 | } | |
2840 | } | |
2841 | ||
ff69416e | 2842 | free_block(cachep, ac->entry, batchcount, node); |
b28a02de | 2843 | free_done: |
1da177e4 LT |
2844 | #if STATS |
2845 | { | |
2846 | int i = 0; | |
2847 | struct list_head *p; | |
2848 | ||
e498be7d CL |
2849 | p = l3->slabs_free.next; |
2850 | while (p != &(l3->slabs_free)) { | |
1da177e4 LT |
2851 | struct slab *slabp; |
2852 | ||
2853 | slabp = list_entry(p, struct slab, list); | |
2854 | BUG_ON(slabp->inuse); | |
2855 | ||
2856 | i++; | |
2857 | p = p->next; | |
2858 | } | |
2859 | STATS_SET_FREEABLE(cachep, i); | |
2860 | } | |
2861 | #endif | |
e498be7d | 2862 | spin_unlock(&l3->list_lock); |
1da177e4 | 2863 | ac->avail -= batchcount; |
e498be7d | 2864 | memmove(ac->entry, &(ac->entry[batchcount]), |
b28a02de | 2865 | sizeof(void *) * ac->avail); |
1da177e4 LT |
2866 | } |
2867 | ||
2868 | /* | |
2869 | * __cache_free | |
2870 | * Release an obj back to its cache. If the obj has a constructed | |
2871 | * state, it must be in this state _before_ it is released. | |
2872 | * | |
2873 | * Called with disabled ints. | |
2874 | */ | |
343e0d7a | 2875 | static inline void __cache_free(struct kmem_cache *cachep, void *objp) |
1da177e4 | 2876 | { |
9a2dba4b | 2877 | struct array_cache *ac = cpu_cache_get(cachep); |
1da177e4 LT |
2878 | |
2879 | check_irq_off(); | |
2880 | objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0)); | |
2881 | ||
e498be7d CL |
2882 | /* Make sure we are not freeing a object from another |
2883 | * node to the array cache on this cpu. | |
2884 | */ | |
2885 | #ifdef CONFIG_NUMA | |
2886 | { | |
2887 | struct slab *slabp; | |
6ed5eb22 | 2888 | slabp = virt_to_slab(objp); |
e498be7d CL |
2889 | if (unlikely(slabp->nodeid != numa_node_id())) { |
2890 | struct array_cache *alien = NULL; | |
2891 | int nodeid = slabp->nodeid; | |
b28a02de PE |
2892 | struct kmem_list3 *l3 = |
2893 | cachep->nodelists[numa_node_id()]; | |
e498be7d CL |
2894 | |
2895 | STATS_INC_NODEFREES(cachep); | |
2896 | if (l3->alien && l3->alien[nodeid]) { | |
2897 | alien = l3->alien[nodeid]; | |
2898 | spin_lock(&alien->lock); | |
2899 | if (unlikely(alien->avail == alien->limit)) | |
2900 | __drain_alien_cache(cachep, | |
b28a02de | 2901 | alien, nodeid); |
e498be7d CL |
2902 | alien->entry[alien->avail++] = objp; |
2903 | spin_unlock(&alien->lock); | |
2904 | } else { | |
2905 | spin_lock(&(cachep->nodelists[nodeid])-> | |
b28a02de | 2906 | list_lock); |
ff69416e | 2907 | free_block(cachep, &objp, 1, nodeid); |
e498be7d | 2908 | spin_unlock(&(cachep->nodelists[nodeid])-> |
b28a02de | 2909 | list_lock); |
e498be7d CL |
2910 | } |
2911 | return; | |
2912 | } | |
2913 | } | |
2914 | #endif | |
1da177e4 LT |
2915 | if (likely(ac->avail < ac->limit)) { |
2916 | STATS_INC_FREEHIT(cachep); | |
e498be7d | 2917 | ac->entry[ac->avail++] = objp; |
1da177e4 LT |
2918 | return; |
2919 | } else { | |
2920 | STATS_INC_FREEMISS(cachep); | |
2921 | cache_flusharray(cachep, ac); | |
e498be7d | 2922 | ac->entry[ac->avail++] = objp; |
1da177e4 LT |
2923 | } |
2924 | } | |
2925 | ||
2926 | /** | |
2927 | * kmem_cache_alloc - Allocate an object | |
2928 | * @cachep: The cache to allocate from. | |
2929 | * @flags: See kmalloc(). | |
2930 | * | |
2931 | * Allocate an object from this cache. The flags are only relevant | |
2932 | * if the cache has no available objects. | |
2933 | */ | |
343e0d7a | 2934 | void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 | 2935 | { |
7fd6b141 | 2936 | return __cache_alloc(cachep, flags, __builtin_return_address(0)); |
1da177e4 LT |
2937 | } |
2938 | EXPORT_SYMBOL(kmem_cache_alloc); | |
2939 | ||
2940 | /** | |
2941 | * kmem_ptr_validate - check if an untrusted pointer might | |
2942 | * be a slab entry. | |
2943 | * @cachep: the cache we're checking against | |
2944 | * @ptr: pointer to validate | |
2945 | * | |
2946 | * This verifies that the untrusted pointer looks sane: | |
2947 | * it is _not_ a guarantee that the pointer is actually | |
2948 | * part of the slab cache in question, but it at least | |
2949 | * validates that the pointer can be dereferenced and | |
2950 | * looks half-way sane. | |
2951 | * | |
2952 | * Currently only used for dentry validation. | |
2953 | */ | |
343e0d7a | 2954 | int fastcall kmem_ptr_validate(struct kmem_cache *cachep, void *ptr) |
1da177e4 | 2955 | { |
b28a02de | 2956 | unsigned long addr = (unsigned long)ptr; |
1da177e4 | 2957 | unsigned long min_addr = PAGE_OFFSET; |
b28a02de | 2958 | unsigned long align_mask = BYTES_PER_WORD - 1; |
3dafccf2 | 2959 | unsigned long size = cachep->buffer_size; |
1da177e4 LT |
2960 | struct page *page; |
2961 | ||
2962 | if (unlikely(addr < min_addr)) | |
2963 | goto out; | |
2964 | if (unlikely(addr > (unsigned long)high_memory - size)) | |
2965 | goto out; | |
2966 | if (unlikely(addr & align_mask)) | |
2967 | goto out; | |
2968 | if (unlikely(!kern_addr_valid(addr))) | |
2969 | goto out; | |
2970 | if (unlikely(!kern_addr_valid(addr + size - 1))) | |
2971 | goto out; | |
2972 | page = virt_to_page(ptr); | |
2973 | if (unlikely(!PageSlab(page))) | |
2974 | goto out; | |
065d41cb | 2975 | if (unlikely(page_get_cache(page) != cachep)) |
1da177e4 LT |
2976 | goto out; |
2977 | return 1; | |
b28a02de | 2978 | out: |
1da177e4 LT |
2979 | return 0; |
2980 | } | |
2981 | ||
2982 | #ifdef CONFIG_NUMA | |
2983 | /** | |
2984 | * kmem_cache_alloc_node - Allocate an object on the specified node | |
2985 | * @cachep: The cache to allocate from. | |
2986 | * @flags: See kmalloc(). | |
2987 | * @nodeid: node number of the target node. | |
2988 | * | |
2989 | * Identical to kmem_cache_alloc, except that this function is slow | |
2990 | * and can sleep. And it will allocate memory on the given node, which | |
2991 | * can improve the performance for cpu bound structures. | |
e498be7d CL |
2992 | * New and improved: it will now make sure that the object gets |
2993 | * put on the correct node list so that there is no false sharing. | |
1da177e4 | 2994 | */ |
343e0d7a | 2995 | void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 | 2996 | { |
e498be7d CL |
2997 | unsigned long save_flags; |
2998 | void *ptr; | |
1da177e4 | 2999 | |
e498be7d CL |
3000 | cache_alloc_debugcheck_before(cachep, flags); |
3001 | local_irq_save(save_flags); | |
18f820f6 CL |
3002 | |
3003 | if (nodeid == -1 || nodeid == numa_node_id() || | |
3004 | !cachep->nodelists[nodeid]) | |
5c382300 AK |
3005 | ptr = ____cache_alloc(cachep, flags); |
3006 | else | |
3007 | ptr = __cache_alloc_node(cachep, flags, nodeid); | |
e498be7d | 3008 | local_irq_restore(save_flags); |
18f820f6 CL |
3009 | |
3010 | ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, | |
3011 | __builtin_return_address(0)); | |
1da177e4 | 3012 | |
e498be7d | 3013 | return ptr; |
1da177e4 LT |
3014 | } |
3015 | EXPORT_SYMBOL(kmem_cache_alloc_node); | |
3016 | ||
dd0fc66f | 3017 | void *kmalloc_node(size_t size, gfp_t flags, int node) |
97e2bde4 | 3018 | { |
343e0d7a | 3019 | struct kmem_cache *cachep; |
97e2bde4 MS |
3020 | |
3021 | cachep = kmem_find_general_cachep(size, flags); | |
3022 | if (unlikely(cachep == NULL)) | |
3023 | return NULL; | |
3024 | return kmem_cache_alloc_node(cachep, flags, node); | |
3025 | } | |
3026 | EXPORT_SYMBOL(kmalloc_node); | |
1da177e4 LT |
3027 | #endif |
3028 | ||
3029 | /** | |
3030 | * kmalloc - allocate memory | |
3031 | * @size: how many bytes of memory are required. | |
3032 | * @flags: the type of memory to allocate. | |
3033 | * | |
3034 | * kmalloc is the normal method of allocating memory | |
3035 | * in the kernel. | |
3036 | * | |
3037 | * The @flags argument may be one of: | |
3038 | * | |
3039 | * %GFP_USER - Allocate memory on behalf of user. May sleep. | |
3040 | * | |
3041 | * %GFP_KERNEL - Allocate normal kernel ram. May sleep. | |
3042 | * | |
3043 | * %GFP_ATOMIC - Allocation will not sleep. Use inside interrupt handlers. | |
3044 | * | |
3045 | * Additionally, the %GFP_DMA flag may be set to indicate the memory | |
3046 | * must be suitable for DMA. This can mean different things on different | |
3047 | * platforms. For example, on i386, it means that the memory must come | |
3048 | * from the first 16MB. | |
3049 | */ | |
7fd6b141 PE |
3050 | static __always_inline void *__do_kmalloc(size_t size, gfp_t flags, |
3051 | void *caller) | |
1da177e4 | 3052 | { |
343e0d7a | 3053 | struct kmem_cache *cachep; |
1da177e4 | 3054 | |
97e2bde4 MS |
3055 | /* If you want to save a few bytes .text space: replace |
3056 | * __ with kmem_. | |
3057 | * Then kmalloc uses the uninlined functions instead of the inline | |
3058 | * functions. | |
3059 | */ | |
3060 | cachep = __find_general_cachep(size, flags); | |
dbdb9045 AM |
3061 | if (unlikely(cachep == NULL)) |
3062 | return NULL; | |
7fd6b141 PE |
3063 | return __cache_alloc(cachep, flags, caller); |
3064 | } | |
3065 | ||
3066 | #ifndef CONFIG_DEBUG_SLAB | |
3067 | ||
3068 | void *__kmalloc(size_t size, gfp_t flags) | |
3069 | { | |
3070 | return __do_kmalloc(size, flags, NULL); | |
1da177e4 LT |
3071 | } |
3072 | EXPORT_SYMBOL(__kmalloc); | |
3073 | ||
7fd6b141 PE |
3074 | #else |
3075 | ||
3076 | void *__kmalloc_track_caller(size_t size, gfp_t flags, void *caller) | |
3077 | { | |
3078 | return __do_kmalloc(size, flags, caller); | |
3079 | } | |
3080 | EXPORT_SYMBOL(__kmalloc_track_caller); | |
3081 | ||
3082 | #endif | |
3083 | ||
1da177e4 LT |
3084 | #ifdef CONFIG_SMP |
3085 | /** | |
3086 | * __alloc_percpu - allocate one copy of the object for every present | |
3087 | * cpu in the system, zeroing them. | |
3088 | * Objects should be dereferenced using the per_cpu_ptr macro only. | |
3089 | * | |
3090 | * @size: how many bytes of memory are required. | |
1da177e4 | 3091 | */ |
f9f75005 | 3092 | void *__alloc_percpu(size_t size) |
1da177e4 LT |
3093 | { |
3094 | int i; | |
b28a02de | 3095 | struct percpu_data *pdata = kmalloc(sizeof(*pdata), GFP_KERNEL); |
1da177e4 LT |
3096 | |
3097 | if (!pdata) | |
3098 | return NULL; | |
3099 | ||
e498be7d CL |
3100 | /* |
3101 | * Cannot use for_each_online_cpu since a cpu may come online | |
3102 | * and we have no way of figuring out how to fix the array | |
3103 | * that we have allocated then.... | |
3104 | */ | |
3105 | for_each_cpu(i) { | |
3106 | int node = cpu_to_node(i); | |
3107 | ||
3108 | if (node_online(node)) | |
3109 | pdata->ptrs[i] = kmalloc_node(size, GFP_KERNEL, node); | |
3110 | else | |
3111 | pdata->ptrs[i] = kmalloc(size, GFP_KERNEL); | |
1da177e4 LT |
3112 | |
3113 | if (!pdata->ptrs[i]) | |
3114 | goto unwind_oom; | |
3115 | memset(pdata->ptrs[i], 0, size); | |
3116 | } | |
3117 | ||
3118 | /* Catch derefs w/o wrappers */ | |
b28a02de | 3119 | return (void *)(~(unsigned long)pdata); |
1da177e4 | 3120 | |
b28a02de | 3121 | unwind_oom: |
1da177e4 LT |
3122 | while (--i >= 0) { |
3123 | if (!cpu_possible(i)) | |
3124 | continue; | |
3125 | kfree(pdata->ptrs[i]); | |
3126 | } | |
3127 | kfree(pdata); | |
3128 | return NULL; | |
3129 | } | |
3130 | EXPORT_SYMBOL(__alloc_percpu); | |
3131 | #endif | |
3132 | ||
3133 | /** | |
3134 | * kmem_cache_free - Deallocate an object | |
3135 | * @cachep: The cache the allocation was from. | |
3136 | * @objp: The previously allocated object. | |
3137 | * | |
3138 | * Free an object which was previously allocated from this | |
3139 | * cache. | |
3140 | */ | |
343e0d7a | 3141 | void kmem_cache_free(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
3142 | { |
3143 | unsigned long flags; | |
3144 | ||
3145 | local_irq_save(flags); | |
3146 | __cache_free(cachep, objp); | |
3147 | local_irq_restore(flags); | |
3148 | } | |
3149 | EXPORT_SYMBOL(kmem_cache_free); | |
3150 | ||
1da177e4 LT |
3151 | /** |
3152 | * kfree - free previously allocated memory | |
3153 | * @objp: pointer returned by kmalloc. | |
3154 | * | |
80e93eff PE |
3155 | * If @objp is NULL, no operation is performed. |
3156 | * | |
1da177e4 LT |
3157 | * Don't free memory not originally allocated by kmalloc() |
3158 | * or you will run into trouble. | |
3159 | */ | |
3160 | void kfree(const void *objp) | |
3161 | { | |
343e0d7a | 3162 | struct kmem_cache *c; |
1da177e4 LT |
3163 | unsigned long flags; |
3164 | ||
3165 | if (unlikely(!objp)) | |
3166 | return; | |
3167 | local_irq_save(flags); | |
3168 | kfree_debugcheck(objp); | |
6ed5eb22 | 3169 | c = virt_to_cache(objp); |
3dafccf2 | 3170 | mutex_debug_check_no_locks_freed(objp, obj_size(c)); |
b28a02de | 3171 | __cache_free(c, (void *)objp); |
1da177e4 LT |
3172 | local_irq_restore(flags); |
3173 | } | |
3174 | EXPORT_SYMBOL(kfree); | |
3175 | ||
3176 | #ifdef CONFIG_SMP | |
3177 | /** | |
3178 | * free_percpu - free previously allocated percpu memory | |
3179 | * @objp: pointer returned by alloc_percpu. | |
3180 | * | |
3181 | * Don't free memory not originally allocated by alloc_percpu() | |
3182 | * The complemented objp is to check for that. | |
3183 | */ | |
b28a02de | 3184 | void free_percpu(const void *objp) |
1da177e4 LT |
3185 | { |
3186 | int i; | |
b28a02de | 3187 | struct percpu_data *p = (struct percpu_data *)(~(unsigned long)objp); |
1da177e4 | 3188 | |
e498be7d CL |
3189 | /* |
3190 | * We allocate for all cpus so we cannot use for online cpu here. | |
3191 | */ | |
3192 | for_each_cpu(i) | |
b28a02de | 3193 | kfree(p->ptrs[i]); |
1da177e4 LT |
3194 | kfree(p); |
3195 | } | |
3196 | EXPORT_SYMBOL(free_percpu); | |
3197 | #endif | |
3198 | ||
343e0d7a | 3199 | unsigned int kmem_cache_size(struct kmem_cache *cachep) |
1da177e4 | 3200 | { |
3dafccf2 | 3201 | return obj_size(cachep); |
1da177e4 LT |
3202 | } |
3203 | EXPORT_SYMBOL(kmem_cache_size); | |
3204 | ||
343e0d7a | 3205 | const char *kmem_cache_name(struct kmem_cache *cachep) |
1944972d ACM |
3206 | { |
3207 | return cachep->name; | |
3208 | } | |
3209 | EXPORT_SYMBOL_GPL(kmem_cache_name); | |
3210 | ||
e498be7d CL |
3211 | /* |
3212 | * This initializes kmem_list3 for all nodes. | |
3213 | */ | |
343e0d7a | 3214 | static int alloc_kmemlist(struct kmem_cache *cachep) |
e498be7d CL |
3215 | { |
3216 | int node; | |
3217 | struct kmem_list3 *l3; | |
3218 | int err = 0; | |
3219 | ||
3220 | for_each_online_node(node) { | |
3221 | struct array_cache *nc = NULL, *new; | |
3222 | struct array_cache **new_alien = NULL; | |
3223 | #ifdef CONFIG_NUMA | |
3224 | if (!(new_alien = alloc_alien_cache(node, cachep->limit))) | |
3225 | goto fail; | |
3226 | #endif | |
b28a02de PE |
3227 | if (!(new = alloc_arraycache(node, (cachep->shared * |
3228 | cachep->batchcount), | |
3229 | 0xbaadf00d))) | |
e498be7d CL |
3230 | goto fail; |
3231 | if ((l3 = cachep->nodelists[node])) { | |
3232 | ||
3233 | spin_lock_irq(&l3->list_lock); | |
3234 | ||
3235 | if ((nc = cachep->nodelists[node]->shared)) | |
b28a02de | 3236 | free_block(cachep, nc->entry, nc->avail, node); |
e498be7d CL |
3237 | |
3238 | l3->shared = new; | |
3239 | if (!cachep->nodelists[node]->alien) { | |
3240 | l3->alien = new_alien; | |
3241 | new_alien = NULL; | |
3242 | } | |
b28a02de PE |
3243 | l3->free_limit = (1 + nr_cpus_node(node)) * |
3244 | cachep->batchcount + cachep->num; | |
e498be7d CL |
3245 | spin_unlock_irq(&l3->list_lock); |
3246 | kfree(nc); | |
3247 | free_alien_cache(new_alien); | |
3248 | continue; | |
3249 | } | |
3250 | if (!(l3 = kmalloc_node(sizeof(struct kmem_list3), | |
b28a02de | 3251 | GFP_KERNEL, node))) |
e498be7d CL |
3252 | goto fail; |
3253 | ||
3254 | kmem_list3_init(l3); | |
3255 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + | |
b28a02de | 3256 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
e498be7d CL |
3257 | l3->shared = new; |
3258 | l3->alien = new_alien; | |
b28a02de PE |
3259 | l3->free_limit = (1 + nr_cpus_node(node)) * |
3260 | cachep->batchcount + cachep->num; | |
e498be7d CL |
3261 | cachep->nodelists[node] = l3; |
3262 | } | |
3263 | return err; | |
b28a02de | 3264 | fail: |
e498be7d CL |
3265 | err = -ENOMEM; |
3266 | return err; | |
3267 | } | |
3268 | ||
1da177e4 | 3269 | struct ccupdate_struct { |
343e0d7a | 3270 | struct kmem_cache *cachep; |
1da177e4 LT |
3271 | struct array_cache *new[NR_CPUS]; |
3272 | }; | |
3273 | ||
3274 | static void do_ccupdate_local(void *info) | |
3275 | { | |
3276 | struct ccupdate_struct *new = (struct ccupdate_struct *)info; | |
3277 | struct array_cache *old; | |
3278 | ||
3279 | check_irq_off(); | |
9a2dba4b | 3280 | old = cpu_cache_get(new->cachep); |
e498be7d | 3281 | |
1da177e4 LT |
3282 | new->cachep->array[smp_processor_id()] = new->new[smp_processor_id()]; |
3283 | new->new[smp_processor_id()] = old; | |
3284 | } | |
3285 | ||
343e0d7a | 3286 | static int do_tune_cpucache(struct kmem_cache *cachep, int limit, int batchcount, |
b28a02de | 3287 | int shared) |
1da177e4 LT |
3288 | { |
3289 | struct ccupdate_struct new; | |
e498be7d | 3290 | int i, err; |
1da177e4 | 3291 | |
b28a02de | 3292 | memset(&new.new, 0, sizeof(new.new)); |
e498be7d | 3293 | for_each_online_cpu(i) { |
b28a02de PE |
3294 | new.new[i] = |
3295 | alloc_arraycache(cpu_to_node(i), limit, batchcount); | |
e498be7d | 3296 | if (!new.new[i]) { |
b28a02de PE |
3297 | for (i--; i >= 0; i--) |
3298 | kfree(new.new[i]); | |
e498be7d | 3299 | return -ENOMEM; |
1da177e4 LT |
3300 | } |
3301 | } | |
3302 | new.cachep = cachep; | |
3303 | ||
3304 | smp_call_function_all_cpus(do_ccupdate_local, (void *)&new); | |
e498be7d | 3305 | |
1da177e4 LT |
3306 | check_irq_on(); |
3307 | spin_lock_irq(&cachep->spinlock); | |
3308 | cachep->batchcount = batchcount; | |
3309 | cachep->limit = limit; | |
e498be7d | 3310 | cachep->shared = shared; |
1da177e4 LT |
3311 | spin_unlock_irq(&cachep->spinlock); |
3312 | ||
e498be7d | 3313 | for_each_online_cpu(i) { |
1da177e4 LT |
3314 | struct array_cache *ccold = new.new[i]; |
3315 | if (!ccold) | |
3316 | continue; | |
e498be7d | 3317 | spin_lock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
ff69416e | 3318 | free_block(cachep, ccold->entry, ccold->avail, cpu_to_node(i)); |
e498be7d | 3319 | spin_unlock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
1da177e4 LT |
3320 | kfree(ccold); |
3321 | } | |
1da177e4 | 3322 | |
e498be7d CL |
3323 | err = alloc_kmemlist(cachep); |
3324 | if (err) { | |
3325 | printk(KERN_ERR "alloc_kmemlist failed for %s, error %d.\n", | |
b28a02de | 3326 | cachep->name, -err); |
e498be7d | 3327 | BUG(); |
1da177e4 | 3328 | } |
1da177e4 LT |
3329 | return 0; |
3330 | } | |
3331 | ||
343e0d7a | 3332 | static void enable_cpucache(struct kmem_cache *cachep) |
1da177e4 LT |
3333 | { |
3334 | int err; | |
3335 | int limit, shared; | |
3336 | ||
3337 | /* The head array serves three purposes: | |
3338 | * - create a LIFO ordering, i.e. return objects that are cache-warm | |
3339 | * - reduce the number of spinlock operations. | |
3340 | * - reduce the number of linked list operations on the slab and | |
3341 | * bufctl chains: array operations are cheaper. | |
3342 | * The numbers are guessed, we should auto-tune as described by | |
3343 | * Bonwick. | |
3344 | */ | |
3dafccf2 | 3345 | if (cachep->buffer_size > 131072) |
1da177e4 | 3346 | limit = 1; |
3dafccf2 | 3347 | else if (cachep->buffer_size > PAGE_SIZE) |
1da177e4 | 3348 | limit = 8; |
3dafccf2 | 3349 | else if (cachep->buffer_size > 1024) |
1da177e4 | 3350 | limit = 24; |
3dafccf2 | 3351 | else if (cachep->buffer_size > 256) |
1da177e4 LT |
3352 | limit = 54; |
3353 | else | |
3354 | limit = 120; | |
3355 | ||
3356 | /* Cpu bound tasks (e.g. network routing) can exhibit cpu bound | |
3357 | * allocation behaviour: Most allocs on one cpu, most free operations | |
3358 | * on another cpu. For these cases, an efficient object passing between | |
3359 | * cpus is necessary. This is provided by a shared array. The array | |
3360 | * replaces Bonwick's magazine layer. | |
3361 | * On uniprocessor, it's functionally equivalent (but less efficient) | |
3362 | * to a larger limit. Thus disabled by default. | |
3363 | */ | |
3364 | shared = 0; | |
3365 | #ifdef CONFIG_SMP | |
3dafccf2 | 3366 | if (cachep->buffer_size <= PAGE_SIZE) |
1da177e4 LT |
3367 | shared = 8; |
3368 | #endif | |
3369 | ||
3370 | #if DEBUG | |
3371 | /* With debugging enabled, large batchcount lead to excessively | |
3372 | * long periods with disabled local interrupts. Limit the | |
3373 | * batchcount | |
3374 | */ | |
3375 | if (limit > 32) | |
3376 | limit = 32; | |
3377 | #endif | |
b28a02de | 3378 | err = do_tune_cpucache(cachep, limit, (limit + 1) / 2, shared); |
1da177e4 LT |
3379 | if (err) |
3380 | printk(KERN_ERR "enable_cpucache failed for %s, error %d.\n", | |
b28a02de | 3381 | cachep->name, -err); |
1da177e4 LT |
3382 | } |
3383 | ||
343e0d7a | 3384 | static void drain_array_locked(struct kmem_cache *cachep, struct array_cache *ac, |
b28a02de | 3385 | int force, int node) |
1da177e4 LT |
3386 | { |
3387 | int tofree; | |
3388 | ||
e498be7d | 3389 | check_spinlock_acquired_node(cachep, node); |
1da177e4 LT |
3390 | if (ac->touched && !force) { |
3391 | ac->touched = 0; | |
3392 | } else if (ac->avail) { | |
b28a02de | 3393 | tofree = force ? ac->avail : (ac->limit + 4) / 5; |
1da177e4 | 3394 | if (tofree > ac->avail) { |
b28a02de | 3395 | tofree = (ac->avail + 1) / 2; |
1da177e4 | 3396 | } |
ff69416e | 3397 | free_block(cachep, ac->entry, tofree, node); |
1da177e4 | 3398 | ac->avail -= tofree; |
e498be7d | 3399 | memmove(ac->entry, &(ac->entry[tofree]), |
b28a02de | 3400 | sizeof(void *) * ac->avail); |
1da177e4 LT |
3401 | } |
3402 | } | |
3403 | ||
3404 | /** | |
3405 | * cache_reap - Reclaim memory from caches. | |
1e5d5331 | 3406 | * @unused: unused parameter |
1da177e4 LT |
3407 | * |
3408 | * Called from workqueue/eventd every few seconds. | |
3409 | * Purpose: | |
3410 | * - clear the per-cpu caches for this CPU. | |
3411 | * - return freeable pages to the main free memory pool. | |
3412 | * | |
fc0abb14 | 3413 | * If we cannot acquire the cache chain mutex then just give up - we'll |
1da177e4 LT |
3414 | * try again on the next iteration. |
3415 | */ | |
3416 | static void cache_reap(void *unused) | |
3417 | { | |
3418 | struct list_head *walk; | |
e498be7d | 3419 | struct kmem_list3 *l3; |
1da177e4 | 3420 | |
fc0abb14 | 3421 | if (!mutex_trylock(&cache_chain_mutex)) { |
1da177e4 | 3422 | /* Give up. Setup the next iteration. */ |
b28a02de PE |
3423 | schedule_delayed_work(&__get_cpu_var(reap_work), |
3424 | REAPTIMEOUT_CPUC); | |
1da177e4 LT |
3425 | return; |
3426 | } | |
3427 | ||
3428 | list_for_each(walk, &cache_chain) { | |
343e0d7a | 3429 | struct kmem_cache *searchp; |
b28a02de | 3430 | struct list_head *p; |
1da177e4 LT |
3431 | int tofree; |
3432 | struct slab *slabp; | |
3433 | ||
343e0d7a | 3434 | searchp = list_entry(walk, struct kmem_cache, next); |
1da177e4 LT |
3435 | |
3436 | if (searchp->flags & SLAB_NO_REAP) | |
3437 | goto next; | |
3438 | ||
3439 | check_irq_on(); | |
3440 | ||
e498be7d CL |
3441 | l3 = searchp->nodelists[numa_node_id()]; |
3442 | if (l3->alien) | |
3443 | drain_alien_cache(searchp, l3); | |
3444 | spin_lock_irq(&l3->list_lock); | |
1da177e4 | 3445 | |
9a2dba4b | 3446 | drain_array_locked(searchp, cpu_cache_get(searchp), 0, |
b28a02de | 3447 | numa_node_id()); |
1da177e4 | 3448 | |
e498be7d | 3449 | if (time_after(l3->next_reap, jiffies)) |
1da177e4 LT |
3450 | goto next_unlock; |
3451 | ||
e498be7d | 3452 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3; |
1da177e4 | 3453 | |
e498be7d CL |
3454 | if (l3->shared) |
3455 | drain_array_locked(searchp, l3->shared, 0, | |
b28a02de | 3456 | numa_node_id()); |
1da177e4 | 3457 | |
e498be7d CL |
3458 | if (l3->free_touched) { |
3459 | l3->free_touched = 0; | |
1da177e4 LT |
3460 | goto next_unlock; |
3461 | } | |
3462 | ||
b28a02de PE |
3463 | tofree = |
3464 | (l3->free_limit + 5 * searchp->num - | |
3465 | 1) / (5 * searchp->num); | |
1da177e4 | 3466 | do { |
e498be7d CL |
3467 | p = l3->slabs_free.next; |
3468 | if (p == &(l3->slabs_free)) | |
1da177e4 LT |
3469 | break; |
3470 | ||
3471 | slabp = list_entry(p, struct slab, list); | |
3472 | BUG_ON(slabp->inuse); | |
3473 | list_del(&slabp->list); | |
3474 | STATS_INC_REAPED(searchp); | |
3475 | ||
3476 | /* Safe to drop the lock. The slab is no longer | |
3477 | * linked to the cache. | |
3478 | * searchp cannot disappear, we hold | |
3479 | * cache_chain_lock | |
3480 | */ | |
e498be7d CL |
3481 | l3->free_objects -= searchp->num; |
3482 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 3483 | slab_destroy(searchp, slabp); |
e498be7d | 3484 | spin_lock_irq(&l3->list_lock); |
b28a02de PE |
3485 | } while (--tofree > 0); |
3486 | next_unlock: | |
e498be7d | 3487 | spin_unlock_irq(&l3->list_lock); |
b28a02de | 3488 | next: |
1da177e4 LT |
3489 | cond_resched(); |
3490 | } | |
3491 | check_irq_on(); | |
fc0abb14 | 3492 | mutex_unlock(&cache_chain_mutex); |
4ae7c039 | 3493 | drain_remote_pages(); |
1da177e4 | 3494 | /* Setup the next iteration */ |
cd61ef62 | 3495 | schedule_delayed_work(&__get_cpu_var(reap_work), REAPTIMEOUT_CPUC); |
1da177e4 LT |
3496 | } |
3497 | ||
3498 | #ifdef CONFIG_PROC_FS | |
3499 | ||
85289f98 | 3500 | static void print_slabinfo_header(struct seq_file *m) |
1da177e4 | 3501 | { |
85289f98 PE |
3502 | /* |
3503 | * Output format version, so at least we can change it | |
3504 | * without _too_ many complaints. | |
3505 | */ | |
1da177e4 | 3506 | #if STATS |
85289f98 | 3507 | seq_puts(m, "slabinfo - version: 2.1 (statistics)\n"); |
1da177e4 | 3508 | #else |
85289f98 | 3509 | seq_puts(m, "slabinfo - version: 2.1\n"); |
1da177e4 | 3510 | #endif |
85289f98 PE |
3511 | seq_puts(m, "# name <active_objs> <num_objs> <objsize> " |
3512 | "<objperslab> <pagesperslab>"); | |
3513 | seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); | |
3514 | seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); | |
1da177e4 | 3515 | #if STATS |
85289f98 PE |
3516 | seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> " |
3517 | "<error> <maxfreeable> <nodeallocs> <remotefrees>"); | |
3518 | seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>"); | |
1da177e4 | 3519 | #endif |
85289f98 PE |
3520 | seq_putc(m, '\n'); |
3521 | } | |
3522 | ||
3523 | static void *s_start(struct seq_file *m, loff_t *pos) | |
3524 | { | |
3525 | loff_t n = *pos; | |
3526 | struct list_head *p; | |
3527 | ||
fc0abb14 | 3528 | mutex_lock(&cache_chain_mutex); |
85289f98 PE |
3529 | if (!n) |
3530 | print_slabinfo_header(m); | |
1da177e4 LT |
3531 | p = cache_chain.next; |
3532 | while (n--) { | |
3533 | p = p->next; | |
3534 | if (p == &cache_chain) | |
3535 | return NULL; | |
3536 | } | |
343e0d7a | 3537 | return list_entry(p, struct kmem_cache, next); |
1da177e4 LT |
3538 | } |
3539 | ||
3540 | static void *s_next(struct seq_file *m, void *p, loff_t *pos) | |
3541 | { | |
343e0d7a | 3542 | struct kmem_cache *cachep = p; |
1da177e4 LT |
3543 | ++*pos; |
3544 | return cachep->next.next == &cache_chain ? NULL | |
343e0d7a | 3545 | : list_entry(cachep->next.next, struct kmem_cache, next); |
1da177e4 LT |
3546 | } |
3547 | ||
3548 | static void s_stop(struct seq_file *m, void *p) | |
3549 | { | |
fc0abb14 | 3550 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
3551 | } |
3552 | ||
3553 | static int s_show(struct seq_file *m, void *p) | |
3554 | { | |
343e0d7a | 3555 | struct kmem_cache *cachep = p; |
1da177e4 | 3556 | struct list_head *q; |
b28a02de PE |
3557 | struct slab *slabp; |
3558 | unsigned long active_objs; | |
3559 | unsigned long num_objs; | |
3560 | unsigned long active_slabs = 0; | |
3561 | unsigned long num_slabs, free_objects = 0, shared_avail = 0; | |
e498be7d | 3562 | const char *name; |
1da177e4 | 3563 | char *error = NULL; |
e498be7d CL |
3564 | int node; |
3565 | struct kmem_list3 *l3; | |
1da177e4 LT |
3566 | |
3567 | check_irq_on(); | |
3568 | spin_lock_irq(&cachep->spinlock); | |
3569 | active_objs = 0; | |
3570 | num_slabs = 0; | |
e498be7d CL |
3571 | for_each_online_node(node) { |
3572 | l3 = cachep->nodelists[node]; | |
3573 | if (!l3) | |
3574 | continue; | |
3575 | ||
3576 | spin_lock(&l3->list_lock); | |
3577 | ||
b28a02de | 3578 | list_for_each(q, &l3->slabs_full) { |
e498be7d CL |
3579 | slabp = list_entry(q, struct slab, list); |
3580 | if (slabp->inuse != cachep->num && !error) | |
3581 | error = "slabs_full accounting error"; | |
3582 | active_objs += cachep->num; | |
3583 | active_slabs++; | |
3584 | } | |
b28a02de | 3585 | list_for_each(q, &l3->slabs_partial) { |
e498be7d CL |
3586 | slabp = list_entry(q, struct slab, list); |
3587 | if (slabp->inuse == cachep->num && !error) | |
3588 | error = "slabs_partial inuse accounting error"; | |
3589 | if (!slabp->inuse && !error) | |
3590 | error = "slabs_partial/inuse accounting error"; | |
3591 | active_objs += slabp->inuse; | |
3592 | active_slabs++; | |
3593 | } | |
b28a02de | 3594 | list_for_each(q, &l3->slabs_free) { |
e498be7d CL |
3595 | slabp = list_entry(q, struct slab, list); |
3596 | if (slabp->inuse && !error) | |
3597 | error = "slabs_free/inuse accounting error"; | |
3598 | num_slabs++; | |
3599 | } | |
3600 | free_objects += l3->free_objects; | |
3601 | shared_avail += l3->shared->avail; | |
3602 | ||
3603 | spin_unlock(&l3->list_lock); | |
1da177e4 | 3604 | } |
b28a02de PE |
3605 | num_slabs += active_slabs; |
3606 | num_objs = num_slabs * cachep->num; | |
e498be7d | 3607 | if (num_objs - active_objs != free_objects && !error) |
1da177e4 LT |
3608 | error = "free_objects accounting error"; |
3609 | ||
b28a02de | 3610 | name = cachep->name; |
1da177e4 LT |
3611 | if (error) |
3612 | printk(KERN_ERR "slab: cache %s error: %s\n", name, error); | |
3613 | ||
3614 | seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", | |
3dafccf2 | 3615 | name, active_objs, num_objs, cachep->buffer_size, |
b28a02de | 3616 | cachep->num, (1 << cachep->gfporder)); |
1da177e4 | 3617 | seq_printf(m, " : tunables %4u %4u %4u", |
b28a02de | 3618 | cachep->limit, cachep->batchcount, cachep->shared); |
e498be7d | 3619 | seq_printf(m, " : slabdata %6lu %6lu %6lu", |
b28a02de | 3620 | active_slabs, num_slabs, shared_avail); |
1da177e4 | 3621 | #if STATS |
b28a02de | 3622 | { /* list3 stats */ |
1da177e4 LT |
3623 | unsigned long high = cachep->high_mark; |
3624 | unsigned long allocs = cachep->num_allocations; | |
3625 | unsigned long grown = cachep->grown; | |
3626 | unsigned long reaped = cachep->reaped; | |
3627 | unsigned long errors = cachep->errors; | |
3628 | unsigned long max_freeable = cachep->max_freeable; | |
1da177e4 | 3629 | unsigned long node_allocs = cachep->node_allocs; |
e498be7d | 3630 | unsigned long node_frees = cachep->node_frees; |
1da177e4 | 3631 | |
e498be7d | 3632 | seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu \ |
b28a02de | 3633 | %4lu %4lu %4lu %4lu", allocs, high, grown, reaped, errors, max_freeable, node_allocs, node_frees); |
1da177e4 LT |
3634 | } |
3635 | /* cpu stats */ | |
3636 | { | |
3637 | unsigned long allochit = atomic_read(&cachep->allochit); | |
3638 | unsigned long allocmiss = atomic_read(&cachep->allocmiss); | |
3639 | unsigned long freehit = atomic_read(&cachep->freehit); | |
3640 | unsigned long freemiss = atomic_read(&cachep->freemiss); | |
3641 | ||
3642 | seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", | |
b28a02de | 3643 | allochit, allocmiss, freehit, freemiss); |
1da177e4 LT |
3644 | } |
3645 | #endif | |
3646 | seq_putc(m, '\n'); | |
3647 | spin_unlock_irq(&cachep->spinlock); | |
3648 | return 0; | |
3649 | } | |
3650 | ||
3651 | /* | |
3652 | * slabinfo_op - iterator that generates /proc/slabinfo | |
3653 | * | |
3654 | * Output layout: | |
3655 | * cache-name | |
3656 | * num-active-objs | |
3657 | * total-objs | |
3658 | * object size | |
3659 | * num-active-slabs | |
3660 | * total-slabs | |
3661 | * num-pages-per-slab | |
3662 | * + further values on SMP and with statistics enabled | |
3663 | */ | |
3664 | ||
3665 | struct seq_operations slabinfo_op = { | |
b28a02de PE |
3666 | .start = s_start, |
3667 | .next = s_next, | |
3668 | .stop = s_stop, | |
3669 | .show = s_show, | |
1da177e4 LT |
3670 | }; |
3671 | ||
3672 | #define MAX_SLABINFO_WRITE 128 | |
3673 | /** | |
3674 | * slabinfo_write - Tuning for the slab allocator | |
3675 | * @file: unused | |
3676 | * @buffer: user buffer | |
3677 | * @count: data length | |
3678 | * @ppos: unused | |
3679 | */ | |
b28a02de PE |
3680 | ssize_t slabinfo_write(struct file *file, const char __user * buffer, |
3681 | size_t count, loff_t *ppos) | |
1da177e4 | 3682 | { |
b28a02de | 3683 | char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; |
1da177e4 LT |
3684 | int limit, batchcount, shared, res; |
3685 | struct list_head *p; | |
b28a02de | 3686 | |
1da177e4 LT |
3687 | if (count > MAX_SLABINFO_WRITE) |
3688 | return -EINVAL; | |
3689 | if (copy_from_user(&kbuf, buffer, count)) | |
3690 | return -EFAULT; | |
b28a02de | 3691 | kbuf[MAX_SLABINFO_WRITE] = '\0'; |
1da177e4 LT |
3692 | |
3693 | tmp = strchr(kbuf, ' '); | |
3694 | if (!tmp) | |
3695 | return -EINVAL; | |
3696 | *tmp = '\0'; | |
3697 | tmp++; | |
3698 | if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) | |
3699 | return -EINVAL; | |
3700 | ||
3701 | /* Find the cache in the chain of caches. */ | |
fc0abb14 | 3702 | mutex_lock(&cache_chain_mutex); |
1da177e4 | 3703 | res = -EINVAL; |
b28a02de | 3704 | list_for_each(p, &cache_chain) { |
343e0d7a PE |
3705 | struct kmem_cache *cachep = list_entry(p, struct kmem_cache, |
3706 | next); | |
1da177e4 LT |
3707 | |
3708 | if (!strcmp(cachep->name, kbuf)) { | |
3709 | if (limit < 1 || | |
3710 | batchcount < 1 || | |
b28a02de | 3711 | batchcount > limit || shared < 0) { |
e498be7d | 3712 | res = 0; |
1da177e4 | 3713 | } else { |
e498be7d | 3714 | res = do_tune_cpucache(cachep, limit, |
b28a02de | 3715 | batchcount, shared); |
1da177e4 LT |
3716 | } |
3717 | break; | |
3718 | } | |
3719 | } | |
fc0abb14 | 3720 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
3721 | if (res >= 0) |
3722 | res = count; | |
3723 | return res; | |
3724 | } | |
3725 | #endif | |
3726 | ||
00e145b6 MS |
3727 | /** |
3728 | * ksize - get the actual amount of memory allocated for a given object | |
3729 | * @objp: Pointer to the object | |
3730 | * | |
3731 | * kmalloc may internally round up allocations and return more memory | |
3732 | * than requested. ksize() can be used to determine the actual amount of | |
3733 | * memory allocated. The caller may use this additional memory, even though | |
3734 | * a smaller amount of memory was initially specified with the kmalloc call. | |
3735 | * The caller must guarantee that objp points to a valid object previously | |
3736 | * allocated with either kmalloc() or kmem_cache_alloc(). The object | |
3737 | * must not be freed during the duration of the call. | |
3738 | */ | |
1da177e4 LT |
3739 | unsigned int ksize(const void *objp) |
3740 | { | |
00e145b6 MS |
3741 | if (unlikely(objp == NULL)) |
3742 | return 0; | |
1da177e4 | 3743 | |
6ed5eb22 | 3744 | return obj_size(virt_to_cache(objp)); |
1da177e4 | 3745 | } |