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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 | ||
4484ebf1 | 887 | static void drain_alien_cache(struct kmem_cache *cachep, struct array_cache **alien) |
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) { | |
4484ebf1 | 894 | ac = alien[i]; |
e498be7d CL |
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 | |
7a21ef6f | 903 | |
4484ebf1 RT |
904 | #define drain_alien_cache(cachep, alien) do { } while (0) |
905 | ||
7a21ef6f LT |
906 | static inline struct array_cache **alloc_alien_cache(int node, int limit) |
907 | { | |
908 | return (struct array_cache **) 0x01020304ul; | |
909 | } | |
910 | ||
4484ebf1 RT |
911 | static inline void free_alien_cache(struct array_cache **ac_ptr) |
912 | { | |
913 | } | |
7a21ef6f | 914 | |
e498be7d CL |
915 | #endif |
916 | ||
1da177e4 | 917 | static int __devinit cpuup_callback(struct notifier_block *nfb, |
b28a02de | 918 | unsigned long action, void *hcpu) |
1da177e4 LT |
919 | { |
920 | long cpu = (long)hcpu; | |
343e0d7a | 921 | struct kmem_cache *cachep; |
e498be7d CL |
922 | struct kmem_list3 *l3 = NULL; |
923 | int node = cpu_to_node(cpu); | |
924 | int memsize = sizeof(struct kmem_list3); | |
1da177e4 LT |
925 | |
926 | switch (action) { | |
927 | case CPU_UP_PREPARE: | |
fc0abb14 | 928 | mutex_lock(&cache_chain_mutex); |
e498be7d CL |
929 | /* we need to do this right in the beginning since |
930 | * alloc_arraycache's are going to use this list. | |
931 | * kmalloc_node allows us to add the slab to the right | |
932 | * kmem_list3 and not this cpu's kmem_list3 | |
933 | */ | |
934 | ||
1da177e4 | 935 | list_for_each_entry(cachep, &cache_chain, next) { |
e498be7d CL |
936 | /* setup the size64 kmemlist for cpu before we can |
937 | * begin anything. Make sure some other cpu on this | |
938 | * node has not already allocated this | |
939 | */ | |
940 | if (!cachep->nodelists[node]) { | |
941 | if (!(l3 = kmalloc_node(memsize, | |
b28a02de | 942 | GFP_KERNEL, node))) |
e498be7d CL |
943 | goto bad; |
944 | kmem_list3_init(l3); | |
945 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + | |
b28a02de | 946 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
e498be7d | 947 | |
4484ebf1 RT |
948 | /* |
949 | * The l3s don't come and go as CPUs come and | |
950 | * go. cache_chain_mutex is sufficient | |
951 | * protection here. | |
952 | */ | |
e498be7d CL |
953 | cachep->nodelists[node] = l3; |
954 | } | |
1da177e4 | 955 | |
e498be7d CL |
956 | spin_lock_irq(&cachep->nodelists[node]->list_lock); |
957 | cachep->nodelists[node]->free_limit = | |
b28a02de PE |
958 | (1 + nr_cpus_node(node)) * |
959 | cachep->batchcount + cachep->num; | |
e498be7d CL |
960 | spin_unlock_irq(&cachep->nodelists[node]->list_lock); |
961 | } | |
962 | ||
963 | /* Now we can go ahead with allocating the shared array's | |
b28a02de | 964 | & array cache's */ |
e498be7d | 965 | list_for_each_entry(cachep, &cache_chain, next) { |
cd105df4 | 966 | struct array_cache *nc; |
4484ebf1 RT |
967 | struct array_cache *shared; |
968 | struct array_cache **alien; | |
cd105df4 | 969 | |
e498be7d | 970 | nc = alloc_arraycache(node, cachep->limit, |
4484ebf1 | 971 | cachep->batchcount); |
1da177e4 LT |
972 | if (!nc) |
973 | goto bad; | |
4484ebf1 RT |
974 | shared = alloc_arraycache(node, |
975 | cachep->shared * cachep->batchcount, | |
976 | 0xbaadf00d); | |
977 | if (!shared) | |
978 | goto bad; | |
7a21ef6f | 979 | |
4484ebf1 RT |
980 | alien = alloc_alien_cache(node, cachep->limit); |
981 | if (!alien) | |
982 | goto bad; | |
1da177e4 | 983 | cachep->array[cpu] = nc; |
1da177e4 | 984 | |
e498be7d CL |
985 | l3 = cachep->nodelists[node]; |
986 | BUG_ON(!l3); | |
e498be7d | 987 | |
4484ebf1 RT |
988 | spin_lock_irq(&l3->list_lock); |
989 | if (!l3->shared) { | |
990 | /* | |
991 | * We are serialised from CPU_DEAD or | |
992 | * CPU_UP_CANCELLED by the cpucontrol lock | |
993 | */ | |
994 | l3->shared = shared; | |
995 | shared = NULL; | |
e498be7d | 996 | } |
4484ebf1 RT |
997 | #ifdef CONFIG_NUMA |
998 | if (!l3->alien) { | |
999 | l3->alien = alien; | |
1000 | alien = NULL; | |
1001 | } | |
1002 | #endif | |
1003 | spin_unlock_irq(&l3->list_lock); | |
1004 | ||
1005 | kfree(shared); | |
1006 | free_alien_cache(alien); | |
1da177e4 | 1007 | } |
fc0abb14 | 1008 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1009 | break; |
1010 | case CPU_ONLINE: | |
1011 | start_cpu_timer(cpu); | |
1012 | break; | |
1013 | #ifdef CONFIG_HOTPLUG_CPU | |
1014 | case CPU_DEAD: | |
4484ebf1 RT |
1015 | /* |
1016 | * Even if all the cpus of a node are down, we don't free the | |
1017 | * kmem_list3 of any cache. This to avoid a race between | |
1018 | * cpu_down, and a kmalloc allocation from another cpu for | |
1019 | * memory from the node of the cpu going down. The list3 | |
1020 | * structure is usually allocated from kmem_cache_create() and | |
1021 | * gets destroyed at kmem_cache_destroy(). | |
1022 | */ | |
1da177e4 LT |
1023 | /* fall thru */ |
1024 | case CPU_UP_CANCELED: | |
fc0abb14 | 1025 | mutex_lock(&cache_chain_mutex); |
1da177e4 LT |
1026 | |
1027 | list_for_each_entry(cachep, &cache_chain, next) { | |
1028 | struct array_cache *nc; | |
4484ebf1 RT |
1029 | struct array_cache *shared; |
1030 | struct array_cache **alien; | |
e498be7d | 1031 | cpumask_t mask; |
1da177e4 | 1032 | |
e498be7d | 1033 | mask = node_to_cpumask(node); |
1da177e4 LT |
1034 | /* cpu is dead; no one can alloc from it. */ |
1035 | nc = cachep->array[cpu]; | |
1036 | cachep->array[cpu] = NULL; | |
e498be7d CL |
1037 | l3 = cachep->nodelists[node]; |
1038 | ||
1039 | if (!l3) | |
4484ebf1 | 1040 | goto free_array_cache; |
e498be7d | 1041 | |
ca3b9b91 | 1042 | spin_lock_irq(&l3->list_lock); |
e498be7d CL |
1043 | |
1044 | /* Free limit for this kmem_list3 */ | |
1045 | l3->free_limit -= cachep->batchcount; | |
1046 | if (nc) | |
ff69416e | 1047 | free_block(cachep, nc->entry, nc->avail, node); |
e498be7d CL |
1048 | |
1049 | if (!cpus_empty(mask)) { | |
ca3b9b91 | 1050 | spin_unlock_irq(&l3->list_lock); |
4484ebf1 | 1051 | goto free_array_cache; |
b28a02de | 1052 | } |
e498be7d | 1053 | |
4484ebf1 RT |
1054 | shared = l3->shared; |
1055 | if (shared) { | |
e498be7d | 1056 | free_block(cachep, l3->shared->entry, |
b28a02de | 1057 | l3->shared->avail, node); |
e498be7d CL |
1058 | l3->shared = NULL; |
1059 | } | |
e498be7d | 1060 | |
4484ebf1 RT |
1061 | alien = l3->alien; |
1062 | l3->alien = NULL; | |
1063 | ||
1064 | spin_unlock_irq(&l3->list_lock); | |
1065 | ||
1066 | kfree(shared); | |
1067 | if (alien) { | |
1068 | drain_alien_cache(cachep, alien); | |
1069 | free_alien_cache(alien); | |
e498be7d | 1070 | } |
4484ebf1 | 1071 | free_array_cache: |
1da177e4 LT |
1072 | kfree(nc); |
1073 | } | |
4484ebf1 RT |
1074 | /* |
1075 | * In the previous loop, all the objects were freed to | |
1076 | * the respective cache's slabs, now we can go ahead and | |
1077 | * shrink each nodelist to its limit. | |
1078 | */ | |
1079 | list_for_each_entry(cachep, &cache_chain, next) { | |
1080 | l3 = cachep->nodelists[node]; | |
1081 | if (!l3) | |
1082 | continue; | |
1083 | spin_lock_irq(&l3->list_lock); | |
1084 | /* free slabs belonging to this node */ | |
1085 | __node_shrink(cachep, node); | |
1086 | spin_unlock_irq(&l3->list_lock); | |
1087 | } | |
fc0abb14 | 1088 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1089 | break; |
1090 | #endif | |
1091 | } | |
1092 | return NOTIFY_OK; | |
b28a02de | 1093 | bad: |
fc0abb14 | 1094 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1095 | return NOTIFY_BAD; |
1096 | } | |
1097 | ||
1098 | static struct notifier_block cpucache_notifier = { &cpuup_callback, NULL, 0 }; | |
1099 | ||
e498be7d CL |
1100 | /* |
1101 | * swap the static kmem_list3 with kmalloced memory | |
1102 | */ | |
343e0d7a | 1103 | static void init_list(struct kmem_cache *cachep, struct kmem_list3 *list, int nodeid) |
e498be7d CL |
1104 | { |
1105 | struct kmem_list3 *ptr; | |
1106 | ||
1107 | BUG_ON(cachep->nodelists[nodeid] != list); | |
1108 | ptr = kmalloc_node(sizeof(struct kmem_list3), GFP_KERNEL, nodeid); | |
1109 | BUG_ON(!ptr); | |
1110 | ||
1111 | local_irq_disable(); | |
1112 | memcpy(ptr, list, sizeof(struct kmem_list3)); | |
1113 | MAKE_ALL_LISTS(cachep, ptr, nodeid); | |
1114 | cachep->nodelists[nodeid] = ptr; | |
1115 | local_irq_enable(); | |
1116 | } | |
1117 | ||
1da177e4 LT |
1118 | /* Initialisation. |
1119 | * Called after the gfp() functions have been enabled, and before smp_init(). | |
1120 | */ | |
1121 | void __init kmem_cache_init(void) | |
1122 | { | |
1123 | size_t left_over; | |
1124 | struct cache_sizes *sizes; | |
1125 | struct cache_names *names; | |
e498be7d | 1126 | int i; |
07ed76b2 | 1127 | int order; |
e498be7d CL |
1128 | |
1129 | for (i = 0; i < NUM_INIT_LISTS; i++) { | |
1130 | kmem_list3_init(&initkmem_list3[i]); | |
1131 | if (i < MAX_NUMNODES) | |
1132 | cache_cache.nodelists[i] = NULL; | |
1133 | } | |
1da177e4 LT |
1134 | |
1135 | /* | |
1136 | * Fragmentation resistance on low memory - only use bigger | |
1137 | * page orders on machines with more than 32MB of memory. | |
1138 | */ | |
1139 | if (num_physpages > (32 << 20) >> PAGE_SHIFT) | |
1140 | slab_break_gfp_order = BREAK_GFP_ORDER_HI; | |
1141 | ||
1da177e4 LT |
1142 | /* Bootstrap is tricky, because several objects are allocated |
1143 | * from caches that do not exist yet: | |
343e0d7a | 1144 | * 1) initialize the cache_cache cache: it contains the struct kmem_cache |
1da177e4 LT |
1145 | * structures of all caches, except cache_cache itself: cache_cache |
1146 | * is statically allocated. | |
e498be7d CL |
1147 | * Initially an __init data area is used for the head array and the |
1148 | * kmem_list3 structures, it's replaced with a kmalloc allocated | |
1149 | * array at the end of the bootstrap. | |
1da177e4 | 1150 | * 2) Create the first kmalloc cache. |
343e0d7a | 1151 | * The struct kmem_cache for the new cache is allocated normally. |
e498be7d CL |
1152 | * An __init data area is used for the head array. |
1153 | * 3) Create the remaining kmalloc caches, with minimally sized | |
1154 | * head arrays. | |
1da177e4 LT |
1155 | * 4) Replace the __init data head arrays for cache_cache and the first |
1156 | * kmalloc cache with kmalloc allocated arrays. | |
e498be7d CL |
1157 | * 5) Replace the __init data for kmem_list3 for cache_cache and |
1158 | * the other cache's with kmalloc allocated memory. | |
1159 | * 6) Resize the head arrays of the kmalloc caches to their final sizes. | |
1da177e4 LT |
1160 | */ |
1161 | ||
1162 | /* 1) create the cache_cache */ | |
1da177e4 LT |
1163 | INIT_LIST_HEAD(&cache_chain); |
1164 | list_add(&cache_cache.next, &cache_chain); | |
1165 | cache_cache.colour_off = cache_line_size(); | |
1166 | cache_cache.array[smp_processor_id()] = &initarray_cache.cache; | |
e498be7d | 1167 | cache_cache.nodelists[numa_node_id()] = &initkmem_list3[CACHE_CACHE]; |
1da177e4 | 1168 | |
3dafccf2 | 1169 | cache_cache.buffer_size = ALIGN(cache_cache.buffer_size, cache_line_size()); |
1da177e4 | 1170 | |
07ed76b2 JS |
1171 | for (order = 0; order < MAX_ORDER; order++) { |
1172 | cache_estimate(order, cache_cache.buffer_size, | |
1173 | cache_line_size(), 0, &left_over, &cache_cache.num); | |
1174 | if (cache_cache.num) | |
1175 | break; | |
1176 | } | |
1da177e4 LT |
1177 | if (!cache_cache.num) |
1178 | BUG(); | |
07ed76b2 | 1179 | cache_cache.gfporder = order; |
b28a02de | 1180 | cache_cache.colour = left_over / cache_cache.colour_off; |
b28a02de PE |
1181 | cache_cache.slab_size = ALIGN(cache_cache.num * sizeof(kmem_bufctl_t) + |
1182 | sizeof(struct slab), cache_line_size()); | |
1da177e4 LT |
1183 | |
1184 | /* 2+3) create the kmalloc caches */ | |
1185 | sizes = malloc_sizes; | |
1186 | names = cache_names; | |
1187 | ||
e498be7d CL |
1188 | /* Initialize the caches that provide memory for the array cache |
1189 | * and the kmem_list3 structures first. | |
1190 | * Without this, further allocations will bug | |
1191 | */ | |
1192 | ||
1193 | sizes[INDEX_AC].cs_cachep = kmem_cache_create(names[INDEX_AC].name, | |
b28a02de PE |
1194 | sizes[INDEX_AC].cs_size, |
1195 | ARCH_KMALLOC_MINALIGN, | |
1196 | (ARCH_KMALLOC_FLAGS | | |
1197 | SLAB_PANIC), NULL, NULL); | |
e498be7d CL |
1198 | |
1199 | if (INDEX_AC != INDEX_L3) | |
1200 | sizes[INDEX_L3].cs_cachep = | |
b28a02de PE |
1201 | kmem_cache_create(names[INDEX_L3].name, |
1202 | sizes[INDEX_L3].cs_size, | |
1203 | ARCH_KMALLOC_MINALIGN, | |
1204 | (ARCH_KMALLOC_FLAGS | SLAB_PANIC), NULL, | |
1205 | NULL); | |
e498be7d | 1206 | |
1da177e4 | 1207 | while (sizes->cs_size != ULONG_MAX) { |
e498be7d CL |
1208 | /* |
1209 | * For performance, all the general caches are L1 aligned. | |
1da177e4 LT |
1210 | * This should be particularly beneficial on SMP boxes, as it |
1211 | * eliminates "false sharing". | |
1212 | * Note for systems short on memory removing the alignment will | |
e498be7d CL |
1213 | * allow tighter packing of the smaller caches. |
1214 | */ | |
b28a02de | 1215 | if (!sizes->cs_cachep) |
e498be7d | 1216 | sizes->cs_cachep = kmem_cache_create(names->name, |
b28a02de PE |
1217 | sizes->cs_size, |
1218 | ARCH_KMALLOC_MINALIGN, | |
1219 | (ARCH_KMALLOC_FLAGS | |
1220 | | SLAB_PANIC), | |
1221 | NULL, NULL); | |
1da177e4 LT |
1222 | |
1223 | /* Inc off-slab bufctl limit until the ceiling is hit. */ | |
1224 | if (!(OFF_SLAB(sizes->cs_cachep))) { | |
b28a02de | 1225 | offslab_limit = sizes->cs_size - sizeof(struct slab); |
1da177e4 LT |
1226 | offslab_limit /= sizeof(kmem_bufctl_t); |
1227 | } | |
1228 | ||
1229 | sizes->cs_dmacachep = kmem_cache_create(names->name_dma, | |
b28a02de PE |
1230 | sizes->cs_size, |
1231 | ARCH_KMALLOC_MINALIGN, | |
1232 | (ARCH_KMALLOC_FLAGS | | |
1233 | SLAB_CACHE_DMA | | |
1234 | SLAB_PANIC), NULL, | |
1235 | NULL); | |
1da177e4 LT |
1236 | |
1237 | sizes++; | |
1238 | names++; | |
1239 | } | |
1240 | /* 4) Replace the bootstrap head arrays */ | |
1241 | { | |
b28a02de | 1242 | void *ptr; |
e498be7d | 1243 | |
1da177e4 | 1244 | ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d | 1245 | |
1da177e4 | 1246 | local_irq_disable(); |
9a2dba4b PE |
1247 | BUG_ON(cpu_cache_get(&cache_cache) != &initarray_cache.cache); |
1248 | memcpy(ptr, cpu_cache_get(&cache_cache), | |
b28a02de | 1249 | sizeof(struct arraycache_init)); |
1da177e4 LT |
1250 | cache_cache.array[smp_processor_id()] = ptr; |
1251 | local_irq_enable(); | |
e498be7d | 1252 | |
1da177e4 | 1253 | ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d | 1254 | |
1da177e4 | 1255 | local_irq_disable(); |
9a2dba4b | 1256 | BUG_ON(cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep) |
b28a02de | 1257 | != &initarray_generic.cache); |
9a2dba4b | 1258 | memcpy(ptr, cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep), |
b28a02de | 1259 | sizeof(struct arraycache_init)); |
e498be7d | 1260 | malloc_sizes[INDEX_AC].cs_cachep->array[smp_processor_id()] = |
b28a02de | 1261 | ptr; |
1da177e4 LT |
1262 | local_irq_enable(); |
1263 | } | |
e498be7d CL |
1264 | /* 5) Replace the bootstrap kmem_list3's */ |
1265 | { | |
1266 | int node; | |
1267 | /* Replace the static kmem_list3 structures for the boot cpu */ | |
1268 | init_list(&cache_cache, &initkmem_list3[CACHE_CACHE], | |
b28a02de | 1269 | numa_node_id()); |
e498be7d CL |
1270 | |
1271 | for_each_online_node(node) { | |
1272 | init_list(malloc_sizes[INDEX_AC].cs_cachep, | |
b28a02de | 1273 | &initkmem_list3[SIZE_AC + node], node); |
e498be7d CL |
1274 | |
1275 | if (INDEX_AC != INDEX_L3) { | |
1276 | init_list(malloc_sizes[INDEX_L3].cs_cachep, | |
b28a02de PE |
1277 | &initkmem_list3[SIZE_L3 + node], |
1278 | node); | |
e498be7d CL |
1279 | } |
1280 | } | |
1281 | } | |
1da177e4 | 1282 | |
e498be7d | 1283 | /* 6) resize the head arrays to their final sizes */ |
1da177e4 | 1284 | { |
343e0d7a | 1285 | struct kmem_cache *cachep; |
fc0abb14 | 1286 | mutex_lock(&cache_chain_mutex); |
1da177e4 | 1287 | list_for_each_entry(cachep, &cache_chain, next) |
b28a02de | 1288 | enable_cpucache(cachep); |
fc0abb14 | 1289 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1290 | } |
1291 | ||
1292 | /* Done! */ | |
1293 | g_cpucache_up = FULL; | |
1294 | ||
1295 | /* Register a cpu startup notifier callback | |
9a2dba4b | 1296 | * that initializes cpu_cache_get for all new cpus |
1da177e4 LT |
1297 | */ |
1298 | register_cpu_notifier(&cpucache_notifier); | |
1da177e4 LT |
1299 | |
1300 | /* The reap timers are started later, with a module init call: | |
1301 | * That part of the kernel is not yet operational. | |
1302 | */ | |
1303 | } | |
1304 | ||
1305 | static int __init cpucache_init(void) | |
1306 | { | |
1307 | int cpu; | |
1308 | ||
1309 | /* | |
1310 | * Register the timers that return unneeded | |
1311 | * pages to gfp. | |
1312 | */ | |
e498be7d | 1313 | for_each_online_cpu(cpu) |
b28a02de | 1314 | start_cpu_timer(cpu); |
1da177e4 LT |
1315 | |
1316 | return 0; | |
1317 | } | |
1318 | ||
1319 | __initcall(cpucache_init); | |
1320 | ||
1321 | /* | |
1322 | * Interface to system's page allocator. No need to hold the cache-lock. | |
1323 | * | |
1324 | * If we requested dmaable memory, we will get it. Even if we | |
1325 | * did not request dmaable memory, we might get it, but that | |
1326 | * would be relatively rare and ignorable. | |
1327 | */ | |
343e0d7a | 1328 | static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 LT |
1329 | { |
1330 | struct page *page; | |
1331 | void *addr; | |
1332 | int i; | |
1333 | ||
1334 | flags |= cachep->gfpflags; | |
50c85a19 | 1335 | page = alloc_pages_node(nodeid, flags, cachep->gfporder); |
1da177e4 LT |
1336 | if (!page) |
1337 | return NULL; | |
1338 | addr = page_address(page); | |
1339 | ||
1340 | i = (1 << cachep->gfporder); | |
1341 | if (cachep->flags & SLAB_RECLAIM_ACCOUNT) | |
1342 | atomic_add(i, &slab_reclaim_pages); | |
1343 | add_page_state(nr_slab, i); | |
1344 | while (i--) { | |
1345 | SetPageSlab(page); | |
1346 | page++; | |
1347 | } | |
1348 | return addr; | |
1349 | } | |
1350 | ||
1351 | /* | |
1352 | * Interface to system's page release. | |
1353 | */ | |
343e0d7a | 1354 | static void kmem_freepages(struct kmem_cache *cachep, void *addr) |
1da177e4 | 1355 | { |
b28a02de | 1356 | unsigned long i = (1 << cachep->gfporder); |
1da177e4 LT |
1357 | struct page *page = virt_to_page(addr); |
1358 | const unsigned long nr_freed = i; | |
1359 | ||
1360 | while (i--) { | |
1361 | if (!TestClearPageSlab(page)) | |
1362 | BUG(); | |
1363 | page++; | |
1364 | } | |
1365 | sub_page_state(nr_slab, nr_freed); | |
1366 | if (current->reclaim_state) | |
1367 | current->reclaim_state->reclaimed_slab += nr_freed; | |
1368 | free_pages((unsigned long)addr, cachep->gfporder); | |
b28a02de PE |
1369 | if (cachep->flags & SLAB_RECLAIM_ACCOUNT) |
1370 | atomic_sub(1 << cachep->gfporder, &slab_reclaim_pages); | |
1da177e4 LT |
1371 | } |
1372 | ||
1373 | static void kmem_rcu_free(struct rcu_head *head) | |
1374 | { | |
b28a02de | 1375 | struct slab_rcu *slab_rcu = (struct slab_rcu *)head; |
343e0d7a | 1376 | struct kmem_cache *cachep = slab_rcu->cachep; |
1da177e4 LT |
1377 | |
1378 | kmem_freepages(cachep, slab_rcu->addr); | |
1379 | if (OFF_SLAB(cachep)) | |
1380 | kmem_cache_free(cachep->slabp_cache, slab_rcu); | |
1381 | } | |
1382 | ||
1383 | #if DEBUG | |
1384 | ||
1385 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
343e0d7a | 1386 | static void store_stackinfo(struct kmem_cache *cachep, unsigned long *addr, |
b28a02de | 1387 | unsigned long caller) |
1da177e4 | 1388 | { |
3dafccf2 | 1389 | int size = obj_size(cachep); |
1da177e4 | 1390 | |
3dafccf2 | 1391 | addr = (unsigned long *)&((char *)addr)[obj_offset(cachep)]; |
1da177e4 | 1392 | |
b28a02de | 1393 | if (size < 5 * sizeof(unsigned long)) |
1da177e4 LT |
1394 | return; |
1395 | ||
b28a02de PE |
1396 | *addr++ = 0x12345678; |
1397 | *addr++ = caller; | |
1398 | *addr++ = smp_processor_id(); | |
1399 | size -= 3 * sizeof(unsigned long); | |
1da177e4 LT |
1400 | { |
1401 | unsigned long *sptr = &caller; | |
1402 | unsigned long svalue; | |
1403 | ||
1404 | while (!kstack_end(sptr)) { | |
1405 | svalue = *sptr++; | |
1406 | if (kernel_text_address(svalue)) { | |
b28a02de | 1407 | *addr++ = svalue; |
1da177e4 LT |
1408 | size -= sizeof(unsigned long); |
1409 | if (size <= sizeof(unsigned long)) | |
1410 | break; | |
1411 | } | |
1412 | } | |
1413 | ||
1414 | } | |
b28a02de | 1415 | *addr++ = 0x87654321; |
1da177e4 LT |
1416 | } |
1417 | #endif | |
1418 | ||
343e0d7a | 1419 | static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val) |
1da177e4 | 1420 | { |
3dafccf2 MS |
1421 | int size = obj_size(cachep); |
1422 | addr = &((char *)addr)[obj_offset(cachep)]; | |
1da177e4 LT |
1423 | |
1424 | memset(addr, val, size); | |
b28a02de | 1425 | *(unsigned char *)(addr + size - 1) = POISON_END; |
1da177e4 LT |
1426 | } |
1427 | ||
1428 | static void dump_line(char *data, int offset, int limit) | |
1429 | { | |
1430 | int i; | |
1431 | printk(KERN_ERR "%03x:", offset); | |
b28a02de PE |
1432 | for (i = 0; i < limit; i++) { |
1433 | printk(" %02x", (unsigned char)data[offset + i]); | |
1da177e4 LT |
1434 | } |
1435 | printk("\n"); | |
1436 | } | |
1437 | #endif | |
1438 | ||
1439 | #if DEBUG | |
1440 | ||
343e0d7a | 1441 | static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines) |
1da177e4 LT |
1442 | { |
1443 | int i, size; | |
1444 | char *realobj; | |
1445 | ||
1446 | if (cachep->flags & SLAB_RED_ZONE) { | |
1447 | printk(KERN_ERR "Redzone: 0x%lx/0x%lx.\n", | |
b28a02de PE |
1448 | *dbg_redzone1(cachep, objp), |
1449 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
1450 | } |
1451 | ||
1452 | if (cachep->flags & SLAB_STORE_USER) { | |
1453 | printk(KERN_ERR "Last user: [<%p>]", | |
b28a02de | 1454 | *dbg_userword(cachep, objp)); |
1da177e4 | 1455 | print_symbol("(%s)", |
b28a02de | 1456 | (unsigned long)*dbg_userword(cachep, objp)); |
1da177e4 LT |
1457 | printk("\n"); |
1458 | } | |
3dafccf2 MS |
1459 | realobj = (char *)objp + obj_offset(cachep); |
1460 | size = obj_size(cachep); | |
b28a02de | 1461 | for (i = 0; i < size && lines; i += 16, lines--) { |
1da177e4 LT |
1462 | int limit; |
1463 | limit = 16; | |
b28a02de PE |
1464 | if (i + limit > size) |
1465 | limit = size - i; | |
1da177e4 LT |
1466 | dump_line(realobj, i, limit); |
1467 | } | |
1468 | } | |
1469 | ||
343e0d7a | 1470 | static void check_poison_obj(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
1471 | { |
1472 | char *realobj; | |
1473 | int size, i; | |
1474 | int lines = 0; | |
1475 | ||
3dafccf2 MS |
1476 | realobj = (char *)objp + obj_offset(cachep); |
1477 | size = obj_size(cachep); | |
1da177e4 | 1478 | |
b28a02de | 1479 | for (i = 0; i < size; i++) { |
1da177e4 | 1480 | char exp = POISON_FREE; |
b28a02de | 1481 | if (i == size - 1) |
1da177e4 LT |
1482 | exp = POISON_END; |
1483 | if (realobj[i] != exp) { | |
1484 | int limit; | |
1485 | /* Mismatch ! */ | |
1486 | /* Print header */ | |
1487 | if (lines == 0) { | |
b28a02de PE |
1488 | printk(KERN_ERR |
1489 | "Slab corruption: start=%p, len=%d\n", | |
1490 | realobj, size); | |
1da177e4 LT |
1491 | print_objinfo(cachep, objp, 0); |
1492 | } | |
1493 | /* Hexdump the affected line */ | |
b28a02de | 1494 | i = (i / 16) * 16; |
1da177e4 | 1495 | limit = 16; |
b28a02de PE |
1496 | if (i + limit > size) |
1497 | limit = size - i; | |
1da177e4 LT |
1498 | dump_line(realobj, i, limit); |
1499 | i += 16; | |
1500 | lines++; | |
1501 | /* Limit to 5 lines */ | |
1502 | if (lines > 5) | |
1503 | break; | |
1504 | } | |
1505 | } | |
1506 | if (lines != 0) { | |
1507 | /* Print some data about the neighboring objects, if they | |
1508 | * exist: | |
1509 | */ | |
6ed5eb22 | 1510 | struct slab *slabp = virt_to_slab(objp); |
1da177e4 LT |
1511 | int objnr; |
1512 | ||
3dafccf2 | 1513 | objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size; |
1da177e4 | 1514 | if (objnr) { |
3dafccf2 MS |
1515 | objp = slabp->s_mem + (objnr - 1) * cachep->buffer_size; |
1516 | realobj = (char *)objp + obj_offset(cachep); | |
1da177e4 | 1517 | printk(KERN_ERR "Prev obj: start=%p, len=%d\n", |
b28a02de | 1518 | realobj, size); |
1da177e4 LT |
1519 | print_objinfo(cachep, objp, 2); |
1520 | } | |
b28a02de | 1521 | if (objnr + 1 < cachep->num) { |
3dafccf2 MS |
1522 | objp = slabp->s_mem + (objnr + 1) * cachep->buffer_size; |
1523 | realobj = (char *)objp + obj_offset(cachep); | |
1da177e4 | 1524 | printk(KERN_ERR "Next obj: start=%p, len=%d\n", |
b28a02de | 1525 | realobj, size); |
1da177e4 LT |
1526 | print_objinfo(cachep, objp, 2); |
1527 | } | |
1528 | } | |
1529 | } | |
1530 | #endif | |
1531 | ||
12dd36fa MD |
1532 | #if DEBUG |
1533 | /** | |
1534 | * slab_destroy_objs - call the registered destructor for each object in | |
1535 | * a slab that is to be destroyed. | |
1da177e4 | 1536 | */ |
343e0d7a | 1537 | static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp) |
1da177e4 | 1538 | { |
1da177e4 LT |
1539 | int i; |
1540 | for (i = 0; i < cachep->num; i++) { | |
3dafccf2 | 1541 | void *objp = slabp->s_mem + cachep->buffer_size * i; |
1da177e4 LT |
1542 | |
1543 | if (cachep->flags & SLAB_POISON) { | |
1544 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
3dafccf2 | 1545 | if ((cachep->buffer_size % PAGE_SIZE) == 0 |
b28a02de PE |
1546 | && OFF_SLAB(cachep)) |
1547 | kernel_map_pages(virt_to_page(objp), | |
3dafccf2 | 1548 | cachep->buffer_size / PAGE_SIZE, |
b28a02de | 1549 | 1); |
1da177e4 LT |
1550 | else |
1551 | check_poison_obj(cachep, objp); | |
1552 | #else | |
1553 | check_poison_obj(cachep, objp); | |
1554 | #endif | |
1555 | } | |
1556 | if (cachep->flags & SLAB_RED_ZONE) { | |
1557 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) | |
1558 | slab_error(cachep, "start of a freed object " | |
b28a02de | 1559 | "was overwritten"); |
1da177e4 LT |
1560 | if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) |
1561 | slab_error(cachep, "end of a freed object " | |
b28a02de | 1562 | "was overwritten"); |
1da177e4 LT |
1563 | } |
1564 | if (cachep->dtor && !(cachep->flags & SLAB_POISON)) | |
3dafccf2 | 1565 | (cachep->dtor) (objp + obj_offset(cachep), cachep, 0); |
1da177e4 | 1566 | } |
12dd36fa | 1567 | } |
1da177e4 | 1568 | #else |
343e0d7a | 1569 | static void slab_destroy_objs(struct kmem_cache *cachep, struct slab *slabp) |
12dd36fa | 1570 | { |
1da177e4 LT |
1571 | if (cachep->dtor) { |
1572 | int i; | |
1573 | for (i = 0; i < cachep->num; i++) { | |
3dafccf2 | 1574 | void *objp = slabp->s_mem + cachep->buffer_size * i; |
b28a02de | 1575 | (cachep->dtor) (objp, cachep, 0); |
1da177e4 LT |
1576 | } |
1577 | } | |
12dd36fa | 1578 | } |
1da177e4 LT |
1579 | #endif |
1580 | ||
12dd36fa MD |
1581 | /** |
1582 | * Destroy all the objs in a slab, and release the mem back to the system. | |
1583 | * Before calling the slab must have been unlinked from the cache. | |
1584 | * The cache-lock is not held/needed. | |
1585 | */ | |
343e0d7a | 1586 | static void slab_destroy(struct kmem_cache *cachep, struct slab *slabp) |
12dd36fa MD |
1587 | { |
1588 | void *addr = slabp->s_mem - slabp->colouroff; | |
1589 | ||
1590 | slab_destroy_objs(cachep, slabp); | |
1da177e4 LT |
1591 | if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) { |
1592 | struct slab_rcu *slab_rcu; | |
1593 | ||
b28a02de | 1594 | slab_rcu = (struct slab_rcu *)slabp; |
1da177e4 LT |
1595 | slab_rcu->cachep = cachep; |
1596 | slab_rcu->addr = addr; | |
1597 | call_rcu(&slab_rcu->head, kmem_rcu_free); | |
1598 | } else { | |
1599 | kmem_freepages(cachep, addr); | |
1600 | if (OFF_SLAB(cachep)) | |
1601 | kmem_cache_free(cachep->slabp_cache, slabp); | |
1602 | } | |
1603 | } | |
1604 | ||
3dafccf2 | 1605 | /* For setting up all the kmem_list3s for cache whose buffer_size is same |
e498be7d | 1606 | as size of kmem_list3. */ |
343e0d7a | 1607 | static void set_up_list3s(struct kmem_cache *cachep, int index) |
e498be7d CL |
1608 | { |
1609 | int node; | |
1610 | ||
1611 | for_each_online_node(node) { | |
b28a02de | 1612 | cachep->nodelists[node] = &initkmem_list3[index + node]; |
e498be7d | 1613 | cachep->nodelists[node]->next_reap = jiffies + |
b28a02de PE |
1614 | REAPTIMEOUT_LIST3 + |
1615 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; | |
e498be7d CL |
1616 | } |
1617 | } | |
1618 | ||
4d268eba | 1619 | /** |
a70773dd RD |
1620 | * calculate_slab_order - calculate size (page order) of slabs |
1621 | * @cachep: pointer to the cache that is being created | |
1622 | * @size: size of objects to be created in this cache. | |
1623 | * @align: required alignment for the objects. | |
1624 | * @flags: slab allocation flags | |
1625 | * | |
1626 | * Also calculates the number of objects per slab. | |
4d268eba PE |
1627 | * |
1628 | * This could be made much more intelligent. For now, try to avoid using | |
1629 | * high order pages for slabs. When the gfp() functions are more friendly | |
1630 | * towards high-order requests, this should be changed. | |
1631 | */ | |
ee13d785 RD |
1632 | static inline size_t calculate_slab_order(struct kmem_cache *cachep, |
1633 | size_t size, size_t align, unsigned long flags) | |
4d268eba PE |
1634 | { |
1635 | size_t left_over = 0; | |
9888e6fa | 1636 | int gfporder; |
4d268eba | 1637 | |
9888e6fa | 1638 | for (gfporder = 0 ; gfporder <= MAX_GFP_ORDER; gfporder++) { |
4d268eba PE |
1639 | unsigned int num; |
1640 | size_t remainder; | |
1641 | ||
9888e6fa | 1642 | cache_estimate(gfporder, size, align, flags, &remainder, &num); |
4d268eba PE |
1643 | if (!num) |
1644 | continue; | |
9888e6fa | 1645 | |
4d268eba | 1646 | /* More than offslab_limit objects will cause problems */ |
9888e6fa | 1647 | if ((flags & CFLGS_OFF_SLAB) && num > offslab_limit) |
4d268eba PE |
1648 | break; |
1649 | ||
9888e6fa | 1650 | /* Found something acceptable - save it away */ |
4d268eba | 1651 | cachep->num = num; |
9888e6fa | 1652 | cachep->gfporder = gfporder; |
4d268eba PE |
1653 | left_over = remainder; |
1654 | ||
f78bb8ad LT |
1655 | /* |
1656 | * A VFS-reclaimable slab tends to have most allocations | |
1657 | * as GFP_NOFS and we really don't want to have to be allocating | |
1658 | * higher-order pages when we are unable to shrink dcache. | |
1659 | */ | |
1660 | if (flags & SLAB_RECLAIM_ACCOUNT) | |
1661 | break; | |
1662 | ||
4d268eba PE |
1663 | /* |
1664 | * Large number of objects is good, but very large slabs are | |
1665 | * currently bad for the gfp()s. | |
1666 | */ | |
9888e6fa | 1667 | if (gfporder >= slab_break_gfp_order) |
4d268eba PE |
1668 | break; |
1669 | ||
9888e6fa LT |
1670 | /* |
1671 | * Acceptable internal fragmentation? | |
1672 | */ | |
1673 | if ((left_over * 8) <= (PAGE_SIZE << gfporder)) | |
4d268eba PE |
1674 | break; |
1675 | } | |
1676 | return left_over; | |
1677 | } | |
1678 | ||
1da177e4 LT |
1679 | /** |
1680 | * kmem_cache_create - Create a cache. | |
1681 | * @name: A string which is used in /proc/slabinfo to identify this cache. | |
1682 | * @size: The size of objects to be created in this cache. | |
1683 | * @align: The required alignment for the objects. | |
1684 | * @flags: SLAB flags | |
1685 | * @ctor: A constructor for the objects. | |
1686 | * @dtor: A destructor for the objects. | |
1687 | * | |
1688 | * Returns a ptr to the cache on success, NULL on failure. | |
1689 | * Cannot be called within a int, but can be interrupted. | |
1690 | * The @ctor is run when new pages are allocated by the cache | |
1691 | * and the @dtor is run before the pages are handed back. | |
1692 | * | |
1693 | * @name must be valid until the cache is destroyed. This implies that | |
1694 | * the module calling this has to destroy the cache before getting | |
1695 | * unloaded. | |
1696 | * | |
1697 | * The flags are | |
1698 | * | |
1699 | * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5) | |
1700 | * to catch references to uninitialised memory. | |
1701 | * | |
1702 | * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check | |
1703 | * for buffer overruns. | |
1704 | * | |
1705 | * %SLAB_NO_REAP - Don't automatically reap this cache when we're under | |
1706 | * memory pressure. | |
1707 | * | |
1708 | * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware | |
1709 | * cacheline. This can be beneficial if you're counting cycles as closely | |
1710 | * as davem. | |
1711 | */ | |
343e0d7a | 1712 | struct kmem_cache * |
1da177e4 | 1713 | kmem_cache_create (const char *name, size_t size, size_t align, |
343e0d7a PE |
1714 | unsigned long flags, void (*ctor)(void*, struct kmem_cache *, unsigned long), |
1715 | void (*dtor)(void*, struct kmem_cache *, unsigned long)) | |
1da177e4 LT |
1716 | { |
1717 | size_t left_over, slab_size, ralign; | |
343e0d7a | 1718 | struct kmem_cache *cachep = NULL; |
4f12bb4f | 1719 | struct list_head *p; |
1da177e4 LT |
1720 | |
1721 | /* | |
1722 | * Sanity checks... these are all serious usage bugs. | |
1723 | */ | |
1724 | if ((!name) || | |
b28a02de PE |
1725 | in_interrupt() || |
1726 | (size < BYTES_PER_WORD) || | |
1727 | (size > (1 << MAX_OBJ_ORDER) * PAGE_SIZE) || (dtor && !ctor)) { | |
1728 | printk(KERN_ERR "%s: Early error in slab %s\n", | |
1729 | __FUNCTION__, name); | |
1730 | BUG(); | |
1731 | } | |
1da177e4 | 1732 | |
f0188f47 RT |
1733 | /* |
1734 | * Prevent CPUs from coming and going. | |
1735 | * lock_cpu_hotplug() nests outside cache_chain_mutex | |
1736 | */ | |
1737 | lock_cpu_hotplug(); | |
1738 | ||
fc0abb14 | 1739 | mutex_lock(&cache_chain_mutex); |
4f12bb4f AM |
1740 | |
1741 | list_for_each(p, &cache_chain) { | |
343e0d7a | 1742 | struct kmem_cache *pc = list_entry(p, struct kmem_cache, next); |
4f12bb4f AM |
1743 | mm_segment_t old_fs = get_fs(); |
1744 | char tmp; | |
1745 | int res; | |
1746 | ||
1747 | /* | |
1748 | * This happens when the module gets unloaded and doesn't | |
1749 | * destroy its slab cache and no-one else reuses the vmalloc | |
1750 | * area of the module. Print a warning. | |
1751 | */ | |
1752 | set_fs(KERNEL_DS); | |
1753 | res = __get_user(tmp, pc->name); | |
1754 | set_fs(old_fs); | |
1755 | if (res) { | |
1756 | printk("SLAB: cache with size %d has lost its name\n", | |
3dafccf2 | 1757 | pc->buffer_size); |
4f12bb4f AM |
1758 | continue; |
1759 | } | |
1760 | ||
b28a02de | 1761 | if (!strcmp(pc->name, name)) { |
4f12bb4f AM |
1762 | printk("kmem_cache_create: duplicate cache %s\n", name); |
1763 | dump_stack(); | |
1764 | goto oops; | |
1765 | } | |
1766 | } | |
1767 | ||
1da177e4 LT |
1768 | #if DEBUG |
1769 | WARN_ON(strchr(name, ' ')); /* It confuses parsers */ | |
1770 | if ((flags & SLAB_DEBUG_INITIAL) && !ctor) { | |
1771 | /* No constructor, but inital state check requested */ | |
1772 | printk(KERN_ERR "%s: No con, but init state check " | |
b28a02de | 1773 | "requested - %s\n", __FUNCTION__, name); |
1da177e4 LT |
1774 | flags &= ~SLAB_DEBUG_INITIAL; |
1775 | } | |
1da177e4 LT |
1776 | #if FORCED_DEBUG |
1777 | /* | |
1778 | * Enable redzoning and last user accounting, except for caches with | |
1779 | * large objects, if the increased size would increase the object size | |
1780 | * above the next power of two: caches with object sizes just above a | |
1781 | * power of two have a significant amount of internal fragmentation. | |
1782 | */ | |
b28a02de PE |
1783 | if ((size < 4096 |
1784 | || fls(size - 1) == fls(size - 1 + 3 * BYTES_PER_WORD))) | |
1785 | flags |= SLAB_RED_ZONE | SLAB_STORE_USER; | |
1da177e4 LT |
1786 | if (!(flags & SLAB_DESTROY_BY_RCU)) |
1787 | flags |= SLAB_POISON; | |
1788 | #endif | |
1789 | if (flags & SLAB_DESTROY_BY_RCU) | |
1790 | BUG_ON(flags & SLAB_POISON); | |
1791 | #endif | |
1792 | if (flags & SLAB_DESTROY_BY_RCU) | |
1793 | BUG_ON(dtor); | |
1794 | ||
1795 | /* | |
1796 | * Always checks flags, a caller might be expecting debug | |
1797 | * support which isn't available. | |
1798 | */ | |
1799 | if (flags & ~CREATE_MASK) | |
1800 | BUG(); | |
1801 | ||
1802 | /* Check that size is in terms of words. This is needed to avoid | |
1803 | * unaligned accesses for some archs when redzoning is used, and makes | |
1804 | * sure any on-slab bufctl's are also correctly aligned. | |
1805 | */ | |
b28a02de PE |
1806 | if (size & (BYTES_PER_WORD - 1)) { |
1807 | size += (BYTES_PER_WORD - 1); | |
1808 | size &= ~(BYTES_PER_WORD - 1); | |
1da177e4 LT |
1809 | } |
1810 | ||
1811 | /* calculate out the final buffer alignment: */ | |
1812 | /* 1) arch recommendation: can be overridden for debug */ | |
1813 | if (flags & SLAB_HWCACHE_ALIGN) { | |
1814 | /* Default alignment: as specified by the arch code. | |
1815 | * Except if an object is really small, then squeeze multiple | |
1816 | * objects into one cacheline. | |
1817 | */ | |
1818 | ralign = cache_line_size(); | |
b28a02de | 1819 | while (size <= ralign / 2) |
1da177e4 LT |
1820 | ralign /= 2; |
1821 | } else { | |
1822 | ralign = BYTES_PER_WORD; | |
1823 | } | |
1824 | /* 2) arch mandated alignment: disables debug if necessary */ | |
1825 | if (ralign < ARCH_SLAB_MINALIGN) { | |
1826 | ralign = ARCH_SLAB_MINALIGN; | |
1827 | if (ralign > BYTES_PER_WORD) | |
b28a02de | 1828 | flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
1da177e4 LT |
1829 | } |
1830 | /* 3) caller mandated alignment: disables debug if necessary */ | |
1831 | if (ralign < align) { | |
1832 | ralign = align; | |
1833 | if (ralign > BYTES_PER_WORD) | |
b28a02de | 1834 | flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
1da177e4 LT |
1835 | } |
1836 | /* 4) Store it. Note that the debug code below can reduce | |
1837 | * the alignment to BYTES_PER_WORD. | |
1838 | */ | |
1839 | align = ralign; | |
1840 | ||
1841 | /* Get cache's description obj. */ | |
343e0d7a | 1842 | cachep = kmem_cache_alloc(&cache_cache, SLAB_KERNEL); |
1da177e4 | 1843 | if (!cachep) |
4f12bb4f | 1844 | goto oops; |
343e0d7a | 1845 | memset(cachep, 0, sizeof(struct kmem_cache)); |
1da177e4 LT |
1846 | |
1847 | #if DEBUG | |
3dafccf2 | 1848 | cachep->obj_size = size; |
1da177e4 LT |
1849 | |
1850 | if (flags & SLAB_RED_ZONE) { | |
1851 | /* redzoning only works with word aligned caches */ | |
1852 | align = BYTES_PER_WORD; | |
1853 | ||
1854 | /* add space for red zone words */ | |
3dafccf2 | 1855 | cachep->obj_offset += BYTES_PER_WORD; |
b28a02de | 1856 | size += 2 * BYTES_PER_WORD; |
1da177e4 LT |
1857 | } |
1858 | if (flags & SLAB_STORE_USER) { | |
1859 | /* user store requires word alignment and | |
1860 | * one word storage behind the end of the real | |
1861 | * object. | |
1862 | */ | |
1863 | align = BYTES_PER_WORD; | |
1864 | size += BYTES_PER_WORD; | |
1865 | } | |
1866 | #if FORCED_DEBUG && defined(CONFIG_DEBUG_PAGEALLOC) | |
b28a02de | 1867 | if (size >= malloc_sizes[INDEX_L3 + 1].cs_size |
3dafccf2 MS |
1868 | && cachep->obj_size > cache_line_size() && size < PAGE_SIZE) { |
1869 | cachep->obj_offset += PAGE_SIZE - size; | |
1da177e4 LT |
1870 | size = PAGE_SIZE; |
1871 | } | |
1872 | #endif | |
1873 | #endif | |
1874 | ||
1875 | /* Determine if the slab management is 'on' or 'off' slab. */ | |
b28a02de | 1876 | if (size >= (PAGE_SIZE >> 3)) |
1da177e4 LT |
1877 | /* |
1878 | * Size is large, assume best to place the slab management obj | |
1879 | * off-slab (should allow better packing of objs). | |
1880 | */ | |
1881 | flags |= CFLGS_OFF_SLAB; | |
1882 | ||
1883 | size = ALIGN(size, align); | |
1884 | ||
f78bb8ad | 1885 | left_over = calculate_slab_order(cachep, size, align, flags); |
1da177e4 LT |
1886 | |
1887 | if (!cachep->num) { | |
1888 | printk("kmem_cache_create: couldn't create cache %s.\n", name); | |
1889 | kmem_cache_free(&cache_cache, cachep); | |
1890 | cachep = NULL; | |
4f12bb4f | 1891 | goto oops; |
1da177e4 | 1892 | } |
b28a02de PE |
1893 | slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t) |
1894 | + sizeof(struct slab), align); | |
1da177e4 LT |
1895 | |
1896 | /* | |
1897 | * If the slab has been placed off-slab, and we have enough space then | |
1898 | * move it on-slab. This is at the expense of any extra colouring. | |
1899 | */ | |
1900 | if (flags & CFLGS_OFF_SLAB && left_over >= slab_size) { | |
1901 | flags &= ~CFLGS_OFF_SLAB; | |
1902 | left_over -= slab_size; | |
1903 | } | |
1904 | ||
1905 | if (flags & CFLGS_OFF_SLAB) { | |
1906 | /* really off slab. No need for manual alignment */ | |
b28a02de PE |
1907 | slab_size = |
1908 | cachep->num * sizeof(kmem_bufctl_t) + sizeof(struct slab); | |
1da177e4 LT |
1909 | } |
1910 | ||
1911 | cachep->colour_off = cache_line_size(); | |
1912 | /* Offset must be a multiple of the alignment. */ | |
1913 | if (cachep->colour_off < align) | |
1914 | cachep->colour_off = align; | |
b28a02de | 1915 | cachep->colour = left_over / cachep->colour_off; |
1da177e4 LT |
1916 | cachep->slab_size = slab_size; |
1917 | cachep->flags = flags; | |
1918 | cachep->gfpflags = 0; | |
1919 | if (flags & SLAB_CACHE_DMA) | |
1920 | cachep->gfpflags |= GFP_DMA; | |
1921 | spin_lock_init(&cachep->spinlock); | |
3dafccf2 | 1922 | cachep->buffer_size = size; |
1da177e4 LT |
1923 | |
1924 | if (flags & CFLGS_OFF_SLAB) | |
b2d55073 | 1925 | cachep->slabp_cache = kmem_find_general_cachep(slab_size, 0u); |
1da177e4 LT |
1926 | cachep->ctor = ctor; |
1927 | cachep->dtor = dtor; | |
1928 | cachep->name = name; | |
1929 | ||
1da177e4 LT |
1930 | |
1931 | if (g_cpucache_up == FULL) { | |
1932 | enable_cpucache(cachep); | |
1933 | } else { | |
1934 | if (g_cpucache_up == NONE) { | |
1935 | /* Note: the first kmem_cache_create must create | |
1936 | * the cache that's used by kmalloc(24), otherwise | |
1937 | * the creation of further caches will BUG(). | |
1938 | */ | |
e498be7d | 1939 | cachep->array[smp_processor_id()] = |
b28a02de | 1940 | &initarray_generic.cache; |
e498be7d CL |
1941 | |
1942 | /* If the cache that's used by | |
1943 | * kmalloc(sizeof(kmem_list3)) is the first cache, | |
1944 | * then we need to set up all its list3s, otherwise | |
1945 | * the creation of further caches will BUG(). | |
1946 | */ | |
1947 | set_up_list3s(cachep, SIZE_AC); | |
1948 | if (INDEX_AC == INDEX_L3) | |
1949 | g_cpucache_up = PARTIAL_L3; | |
1950 | else | |
1951 | g_cpucache_up = PARTIAL_AC; | |
1da177e4 | 1952 | } else { |
e498be7d | 1953 | cachep->array[smp_processor_id()] = |
b28a02de | 1954 | kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d CL |
1955 | |
1956 | if (g_cpucache_up == PARTIAL_AC) { | |
1957 | set_up_list3s(cachep, SIZE_L3); | |
1958 | g_cpucache_up = PARTIAL_L3; | |
1959 | } else { | |
1960 | int node; | |
1961 | for_each_online_node(node) { | |
1962 | ||
1963 | cachep->nodelists[node] = | |
b28a02de PE |
1964 | kmalloc_node(sizeof |
1965 | (struct kmem_list3), | |
1966 | GFP_KERNEL, node); | |
e498be7d | 1967 | BUG_ON(!cachep->nodelists[node]); |
b28a02de PE |
1968 | kmem_list3_init(cachep-> |
1969 | nodelists[node]); | |
e498be7d CL |
1970 | } |
1971 | } | |
1da177e4 | 1972 | } |
e498be7d | 1973 | cachep->nodelists[numa_node_id()]->next_reap = |
b28a02de PE |
1974 | jiffies + REAPTIMEOUT_LIST3 + |
1975 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; | |
e498be7d | 1976 | |
9a2dba4b PE |
1977 | BUG_ON(!cpu_cache_get(cachep)); |
1978 | cpu_cache_get(cachep)->avail = 0; | |
1979 | cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES; | |
1980 | cpu_cache_get(cachep)->batchcount = 1; | |
1981 | cpu_cache_get(cachep)->touched = 0; | |
1da177e4 LT |
1982 | cachep->batchcount = 1; |
1983 | cachep->limit = BOOT_CPUCACHE_ENTRIES; | |
b28a02de | 1984 | } |
1da177e4 | 1985 | |
1da177e4 LT |
1986 | /* cache setup completed, link it into the list */ |
1987 | list_add(&cachep->next, &cache_chain); | |
b28a02de | 1988 | oops: |
1da177e4 LT |
1989 | if (!cachep && (flags & SLAB_PANIC)) |
1990 | panic("kmem_cache_create(): failed to create slab `%s'\n", | |
b28a02de | 1991 | name); |
fc0abb14 | 1992 | mutex_unlock(&cache_chain_mutex); |
f0188f47 | 1993 | unlock_cpu_hotplug(); |
1da177e4 LT |
1994 | return cachep; |
1995 | } | |
1996 | EXPORT_SYMBOL(kmem_cache_create); | |
1997 | ||
1998 | #if DEBUG | |
1999 | static void check_irq_off(void) | |
2000 | { | |
2001 | BUG_ON(!irqs_disabled()); | |
2002 | } | |
2003 | ||
2004 | static void check_irq_on(void) | |
2005 | { | |
2006 | BUG_ON(irqs_disabled()); | |
2007 | } | |
2008 | ||
343e0d7a | 2009 | static void check_spinlock_acquired(struct kmem_cache *cachep) |
1da177e4 LT |
2010 | { |
2011 | #ifdef CONFIG_SMP | |
2012 | check_irq_off(); | |
e498be7d | 2013 | assert_spin_locked(&cachep->nodelists[numa_node_id()]->list_lock); |
1da177e4 LT |
2014 | #endif |
2015 | } | |
e498be7d | 2016 | |
343e0d7a | 2017 | static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node) |
e498be7d CL |
2018 | { |
2019 | #ifdef CONFIG_SMP | |
2020 | check_irq_off(); | |
2021 | assert_spin_locked(&cachep->nodelists[node]->list_lock); | |
2022 | #endif | |
2023 | } | |
2024 | ||
1da177e4 LT |
2025 | #else |
2026 | #define check_irq_off() do { } while(0) | |
2027 | #define check_irq_on() do { } while(0) | |
2028 | #define check_spinlock_acquired(x) do { } while(0) | |
e498be7d | 2029 | #define check_spinlock_acquired_node(x, y) do { } while(0) |
1da177e4 LT |
2030 | #endif |
2031 | ||
2032 | /* | |
2033 | * Waits for all CPUs to execute func(). | |
2034 | */ | |
b28a02de | 2035 | static void smp_call_function_all_cpus(void (*func)(void *arg), void *arg) |
1da177e4 LT |
2036 | { |
2037 | check_irq_on(); | |
2038 | preempt_disable(); | |
2039 | ||
2040 | local_irq_disable(); | |
2041 | func(arg); | |
2042 | local_irq_enable(); | |
2043 | ||
2044 | if (smp_call_function(func, arg, 1, 1)) | |
2045 | BUG(); | |
2046 | ||
2047 | preempt_enable(); | |
2048 | } | |
2049 | ||
343e0d7a | 2050 | static void drain_array_locked(struct kmem_cache *cachep, struct array_cache *ac, |
b28a02de | 2051 | int force, int node); |
1da177e4 LT |
2052 | |
2053 | static void do_drain(void *arg) | |
2054 | { | |
343e0d7a | 2055 | struct kmem_cache *cachep = (struct kmem_cache *) arg; |
1da177e4 | 2056 | struct array_cache *ac; |
ff69416e | 2057 | int node = numa_node_id(); |
1da177e4 LT |
2058 | |
2059 | check_irq_off(); | |
9a2dba4b | 2060 | ac = cpu_cache_get(cachep); |
ff69416e CL |
2061 | spin_lock(&cachep->nodelists[node]->list_lock); |
2062 | free_block(cachep, ac->entry, ac->avail, node); | |
2063 | spin_unlock(&cachep->nodelists[node]->list_lock); | |
1da177e4 LT |
2064 | ac->avail = 0; |
2065 | } | |
2066 | ||
343e0d7a | 2067 | static void drain_cpu_caches(struct kmem_cache *cachep) |
1da177e4 | 2068 | { |
e498be7d CL |
2069 | struct kmem_list3 *l3; |
2070 | int node; | |
2071 | ||
1da177e4 LT |
2072 | smp_call_function_all_cpus(do_drain, cachep); |
2073 | check_irq_on(); | |
b28a02de | 2074 | for_each_online_node(node) { |
e498be7d CL |
2075 | l3 = cachep->nodelists[node]; |
2076 | if (l3) { | |
ca3b9b91 | 2077 | spin_lock_irq(&l3->list_lock); |
e498be7d | 2078 | drain_array_locked(cachep, l3->shared, 1, node); |
ca3b9b91 | 2079 | spin_unlock_irq(&l3->list_lock); |
e498be7d | 2080 | if (l3->alien) |
4484ebf1 | 2081 | drain_alien_cache(cachep, l3->alien); |
e498be7d CL |
2082 | } |
2083 | } | |
1da177e4 LT |
2084 | } |
2085 | ||
343e0d7a | 2086 | static int __node_shrink(struct kmem_cache *cachep, int node) |
1da177e4 LT |
2087 | { |
2088 | struct slab *slabp; | |
e498be7d | 2089 | struct kmem_list3 *l3 = cachep->nodelists[node]; |
1da177e4 LT |
2090 | int ret; |
2091 | ||
e498be7d | 2092 | for (;;) { |
1da177e4 LT |
2093 | struct list_head *p; |
2094 | ||
e498be7d CL |
2095 | p = l3->slabs_free.prev; |
2096 | if (p == &l3->slabs_free) | |
1da177e4 LT |
2097 | break; |
2098 | ||
e498be7d | 2099 | slabp = list_entry(l3->slabs_free.prev, struct slab, list); |
1da177e4 LT |
2100 | #if DEBUG |
2101 | if (slabp->inuse) | |
2102 | BUG(); | |
2103 | #endif | |
2104 | list_del(&slabp->list); | |
2105 | ||
e498be7d CL |
2106 | l3->free_objects -= cachep->num; |
2107 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 2108 | slab_destroy(cachep, slabp); |
e498be7d | 2109 | spin_lock_irq(&l3->list_lock); |
1da177e4 | 2110 | } |
b28a02de | 2111 | ret = !list_empty(&l3->slabs_full) || !list_empty(&l3->slabs_partial); |
1da177e4 LT |
2112 | return ret; |
2113 | } | |
2114 | ||
343e0d7a | 2115 | static int __cache_shrink(struct kmem_cache *cachep) |
e498be7d CL |
2116 | { |
2117 | int ret = 0, i = 0; | |
2118 | struct kmem_list3 *l3; | |
2119 | ||
2120 | drain_cpu_caches(cachep); | |
2121 | ||
2122 | check_irq_on(); | |
2123 | for_each_online_node(i) { | |
2124 | l3 = cachep->nodelists[i]; | |
2125 | if (l3) { | |
2126 | spin_lock_irq(&l3->list_lock); | |
2127 | ret += __node_shrink(cachep, i); | |
2128 | spin_unlock_irq(&l3->list_lock); | |
2129 | } | |
2130 | } | |
2131 | return (ret ? 1 : 0); | |
2132 | } | |
2133 | ||
1da177e4 LT |
2134 | /** |
2135 | * kmem_cache_shrink - Shrink a cache. | |
2136 | * @cachep: The cache to shrink. | |
2137 | * | |
2138 | * Releases as many slabs as possible for a cache. | |
2139 | * To help debugging, a zero exit status indicates all slabs were released. | |
2140 | */ | |
343e0d7a | 2141 | int kmem_cache_shrink(struct kmem_cache *cachep) |
1da177e4 LT |
2142 | { |
2143 | if (!cachep || in_interrupt()) | |
2144 | BUG(); | |
2145 | ||
2146 | return __cache_shrink(cachep); | |
2147 | } | |
2148 | EXPORT_SYMBOL(kmem_cache_shrink); | |
2149 | ||
2150 | /** | |
2151 | * kmem_cache_destroy - delete a cache | |
2152 | * @cachep: the cache to destroy | |
2153 | * | |
343e0d7a | 2154 | * Remove a struct kmem_cache object from the slab cache. |
1da177e4 LT |
2155 | * Returns 0 on success. |
2156 | * | |
2157 | * It is expected this function will be called by a module when it is | |
2158 | * unloaded. This will remove the cache completely, and avoid a duplicate | |
2159 | * cache being allocated each time a module is loaded and unloaded, if the | |
2160 | * module doesn't have persistent in-kernel storage across loads and unloads. | |
2161 | * | |
2162 | * The cache must be empty before calling this function. | |
2163 | * | |
2164 | * The caller must guarantee that noone will allocate memory from the cache | |
2165 | * during the kmem_cache_destroy(). | |
2166 | */ | |
343e0d7a | 2167 | int kmem_cache_destroy(struct kmem_cache *cachep) |
1da177e4 LT |
2168 | { |
2169 | int i; | |
e498be7d | 2170 | struct kmem_list3 *l3; |
1da177e4 LT |
2171 | |
2172 | if (!cachep || in_interrupt()) | |
2173 | BUG(); | |
2174 | ||
2175 | /* Don't let CPUs to come and go */ | |
2176 | lock_cpu_hotplug(); | |
2177 | ||
2178 | /* Find the cache in the chain of caches. */ | |
fc0abb14 | 2179 | mutex_lock(&cache_chain_mutex); |
1da177e4 LT |
2180 | /* |
2181 | * the chain is never empty, cache_cache is never destroyed | |
2182 | */ | |
2183 | list_del(&cachep->next); | |
fc0abb14 | 2184 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
2185 | |
2186 | if (__cache_shrink(cachep)) { | |
2187 | slab_error(cachep, "Can't free all objects"); | |
fc0abb14 | 2188 | mutex_lock(&cache_chain_mutex); |
b28a02de | 2189 | list_add(&cachep->next, &cache_chain); |
fc0abb14 | 2190 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
2191 | unlock_cpu_hotplug(); |
2192 | return 1; | |
2193 | } | |
2194 | ||
2195 | if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) | |
fbd568a3 | 2196 | synchronize_rcu(); |
1da177e4 | 2197 | |
e498be7d | 2198 | for_each_online_cpu(i) |
b28a02de | 2199 | kfree(cachep->array[i]); |
1da177e4 LT |
2200 | |
2201 | /* NUMA: free the list3 structures */ | |
e498be7d CL |
2202 | for_each_online_node(i) { |
2203 | if ((l3 = cachep->nodelists[i])) { | |
2204 | kfree(l3->shared); | |
2205 | free_alien_cache(l3->alien); | |
2206 | kfree(l3); | |
2207 | } | |
2208 | } | |
1da177e4 LT |
2209 | kmem_cache_free(&cache_cache, cachep); |
2210 | ||
2211 | unlock_cpu_hotplug(); | |
2212 | ||
2213 | return 0; | |
2214 | } | |
2215 | EXPORT_SYMBOL(kmem_cache_destroy); | |
2216 | ||
2217 | /* Get the memory for a slab management obj. */ | |
343e0d7a | 2218 | static struct slab *alloc_slabmgmt(struct kmem_cache *cachep, void *objp, |
b28a02de | 2219 | int colour_off, gfp_t local_flags) |
1da177e4 LT |
2220 | { |
2221 | struct slab *slabp; | |
b28a02de | 2222 | |
1da177e4 LT |
2223 | if (OFF_SLAB(cachep)) { |
2224 | /* Slab management obj is off-slab. */ | |
2225 | slabp = kmem_cache_alloc(cachep->slabp_cache, local_flags); | |
2226 | if (!slabp) | |
2227 | return NULL; | |
2228 | } else { | |
b28a02de | 2229 | slabp = objp + colour_off; |
1da177e4 LT |
2230 | colour_off += cachep->slab_size; |
2231 | } | |
2232 | slabp->inuse = 0; | |
2233 | slabp->colouroff = colour_off; | |
b28a02de | 2234 | slabp->s_mem = objp + colour_off; |
1da177e4 LT |
2235 | |
2236 | return slabp; | |
2237 | } | |
2238 | ||
2239 | static inline kmem_bufctl_t *slab_bufctl(struct slab *slabp) | |
2240 | { | |
b28a02de | 2241 | return (kmem_bufctl_t *) (slabp + 1); |
1da177e4 LT |
2242 | } |
2243 | ||
343e0d7a | 2244 | static void cache_init_objs(struct kmem_cache *cachep, |
b28a02de | 2245 | struct slab *slabp, unsigned long ctor_flags) |
1da177e4 LT |
2246 | { |
2247 | int i; | |
2248 | ||
2249 | for (i = 0; i < cachep->num; i++) { | |
3dafccf2 | 2250 | void *objp = slabp->s_mem + cachep->buffer_size * i; |
1da177e4 LT |
2251 | #if DEBUG |
2252 | /* need to poison the objs? */ | |
2253 | if (cachep->flags & SLAB_POISON) | |
2254 | poison_obj(cachep, objp, POISON_FREE); | |
2255 | if (cachep->flags & SLAB_STORE_USER) | |
2256 | *dbg_userword(cachep, objp) = NULL; | |
2257 | ||
2258 | if (cachep->flags & SLAB_RED_ZONE) { | |
2259 | *dbg_redzone1(cachep, objp) = RED_INACTIVE; | |
2260 | *dbg_redzone2(cachep, objp) = RED_INACTIVE; | |
2261 | } | |
2262 | /* | |
2263 | * Constructors are not allowed to allocate memory from | |
2264 | * the same cache which they are a constructor for. | |
2265 | * Otherwise, deadlock. They must also be threaded. | |
2266 | */ | |
2267 | if (cachep->ctor && !(cachep->flags & SLAB_POISON)) | |
3dafccf2 | 2268 | cachep->ctor(objp + obj_offset(cachep), cachep, |
b28a02de | 2269 | ctor_flags); |
1da177e4 LT |
2270 | |
2271 | if (cachep->flags & SLAB_RED_ZONE) { | |
2272 | if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) | |
2273 | slab_error(cachep, "constructor overwrote the" | |
b28a02de | 2274 | " end of an object"); |
1da177e4 LT |
2275 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) |
2276 | slab_error(cachep, "constructor overwrote the" | |
b28a02de | 2277 | " start of an object"); |
1da177e4 | 2278 | } |
3dafccf2 | 2279 | if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep) |
b28a02de PE |
2280 | && cachep->flags & SLAB_POISON) |
2281 | kernel_map_pages(virt_to_page(objp), | |
3dafccf2 | 2282 | cachep->buffer_size / PAGE_SIZE, 0); |
1da177e4 LT |
2283 | #else |
2284 | if (cachep->ctor) | |
2285 | cachep->ctor(objp, cachep, ctor_flags); | |
2286 | #endif | |
b28a02de | 2287 | slab_bufctl(slabp)[i] = i + 1; |
1da177e4 | 2288 | } |
b28a02de | 2289 | slab_bufctl(slabp)[i - 1] = BUFCTL_END; |
1da177e4 LT |
2290 | slabp->free = 0; |
2291 | } | |
2292 | ||
343e0d7a | 2293 | static void kmem_flagcheck(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 LT |
2294 | { |
2295 | if (flags & SLAB_DMA) { | |
2296 | if (!(cachep->gfpflags & GFP_DMA)) | |
2297 | BUG(); | |
2298 | } else { | |
2299 | if (cachep->gfpflags & GFP_DMA) | |
2300 | BUG(); | |
2301 | } | |
2302 | } | |
2303 | ||
343e0d7a | 2304 | static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp, int nodeid) |
78d382d7 MD |
2305 | { |
2306 | void *objp = slabp->s_mem + (slabp->free * cachep->buffer_size); | |
2307 | kmem_bufctl_t next; | |
2308 | ||
2309 | slabp->inuse++; | |
2310 | next = slab_bufctl(slabp)[slabp->free]; | |
2311 | #if DEBUG | |
2312 | slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE; | |
2313 | WARN_ON(slabp->nodeid != nodeid); | |
2314 | #endif | |
2315 | slabp->free = next; | |
2316 | ||
2317 | return objp; | |
2318 | } | |
2319 | ||
343e0d7a | 2320 | static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp, void *objp, |
78d382d7 MD |
2321 | int nodeid) |
2322 | { | |
2323 | unsigned int objnr = (unsigned)(objp-slabp->s_mem) / cachep->buffer_size; | |
2324 | ||
2325 | #if DEBUG | |
2326 | /* Verify that the slab belongs to the intended node */ | |
2327 | WARN_ON(slabp->nodeid != nodeid); | |
2328 | ||
2329 | if (slab_bufctl(slabp)[objnr] != BUFCTL_FREE) { | |
2330 | printk(KERN_ERR "slab: double free detected in cache " | |
2331 | "'%s', objp %p\n", cachep->name, objp); | |
2332 | BUG(); | |
2333 | } | |
2334 | #endif | |
2335 | slab_bufctl(slabp)[objnr] = slabp->free; | |
2336 | slabp->free = objnr; | |
2337 | slabp->inuse--; | |
2338 | } | |
2339 | ||
343e0d7a | 2340 | static void set_slab_attr(struct kmem_cache *cachep, struct slab *slabp, void *objp) |
1da177e4 LT |
2341 | { |
2342 | int i; | |
2343 | struct page *page; | |
2344 | ||
2345 | /* Nasty!!!!!! I hope this is OK. */ | |
2346 | i = 1 << cachep->gfporder; | |
2347 | page = virt_to_page(objp); | |
2348 | do { | |
065d41cb PE |
2349 | page_set_cache(page, cachep); |
2350 | page_set_slab(page, slabp); | |
1da177e4 LT |
2351 | page++; |
2352 | } while (--i); | |
2353 | } | |
2354 | ||
2355 | /* | |
2356 | * Grow (by 1) the number of slabs within a cache. This is called by | |
2357 | * kmem_cache_alloc() when there are no active objs left in a cache. | |
2358 | */ | |
343e0d7a | 2359 | static int cache_grow(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 | 2360 | { |
b28a02de PE |
2361 | struct slab *slabp; |
2362 | void *objp; | |
2363 | size_t offset; | |
2364 | gfp_t local_flags; | |
2365 | unsigned long ctor_flags; | |
e498be7d | 2366 | struct kmem_list3 *l3; |
1da177e4 LT |
2367 | |
2368 | /* Be lazy and only check for valid flags here, | |
b28a02de | 2369 | * keeping it out of the critical path in kmem_cache_alloc(). |
1da177e4 | 2370 | */ |
b28a02de | 2371 | if (flags & ~(SLAB_DMA | SLAB_LEVEL_MASK | SLAB_NO_GROW)) |
1da177e4 LT |
2372 | BUG(); |
2373 | if (flags & SLAB_NO_GROW) | |
2374 | return 0; | |
2375 | ||
2376 | ctor_flags = SLAB_CTOR_CONSTRUCTOR; | |
2377 | local_flags = (flags & SLAB_LEVEL_MASK); | |
2378 | if (!(local_flags & __GFP_WAIT)) | |
2379 | /* | |
2380 | * Not allowed to sleep. Need to tell a constructor about | |
2381 | * this - it might need to know... | |
2382 | */ | |
2383 | ctor_flags |= SLAB_CTOR_ATOMIC; | |
2384 | ||
2e1217cf | 2385 | /* Take the l3 list lock to change the colour_next on this node */ |
1da177e4 | 2386 | check_irq_off(); |
2e1217cf RT |
2387 | l3 = cachep->nodelists[nodeid]; |
2388 | spin_lock(&l3->list_lock); | |
1da177e4 LT |
2389 | |
2390 | /* Get colour for the slab, and cal the next value. */ | |
2e1217cf RT |
2391 | offset = l3->colour_next; |
2392 | l3->colour_next++; | |
2393 | if (l3->colour_next >= cachep->colour) | |
2394 | l3->colour_next = 0; | |
2395 | spin_unlock(&l3->list_lock); | |
1da177e4 | 2396 | |
2e1217cf | 2397 | offset *= cachep->colour_off; |
1da177e4 LT |
2398 | |
2399 | if (local_flags & __GFP_WAIT) | |
2400 | local_irq_enable(); | |
2401 | ||
2402 | /* | |
2403 | * The test for missing atomic flag is performed here, rather than | |
2404 | * the more obvious place, simply to reduce the critical path length | |
2405 | * in kmem_cache_alloc(). If a caller is seriously mis-behaving they | |
2406 | * will eventually be caught here (where it matters). | |
2407 | */ | |
2408 | kmem_flagcheck(cachep, flags); | |
2409 | ||
e498be7d CL |
2410 | /* Get mem for the objs. |
2411 | * Attempt to allocate a physical page from 'nodeid', | |
2412 | */ | |
1da177e4 LT |
2413 | if (!(objp = kmem_getpages(cachep, flags, nodeid))) |
2414 | goto failed; | |
2415 | ||
2416 | /* Get slab management. */ | |
2417 | if (!(slabp = alloc_slabmgmt(cachep, objp, offset, local_flags))) | |
2418 | goto opps1; | |
2419 | ||
e498be7d | 2420 | slabp->nodeid = nodeid; |
1da177e4 LT |
2421 | set_slab_attr(cachep, slabp, objp); |
2422 | ||
2423 | cache_init_objs(cachep, slabp, ctor_flags); | |
2424 | ||
2425 | if (local_flags & __GFP_WAIT) | |
2426 | local_irq_disable(); | |
2427 | check_irq_off(); | |
e498be7d | 2428 | spin_lock(&l3->list_lock); |
1da177e4 LT |
2429 | |
2430 | /* Make slab active. */ | |
e498be7d | 2431 | list_add_tail(&slabp->list, &(l3->slabs_free)); |
1da177e4 | 2432 | STATS_INC_GROWN(cachep); |
e498be7d CL |
2433 | l3->free_objects += cachep->num; |
2434 | spin_unlock(&l3->list_lock); | |
1da177e4 | 2435 | return 1; |
b28a02de | 2436 | opps1: |
1da177e4 | 2437 | kmem_freepages(cachep, objp); |
b28a02de | 2438 | failed: |
1da177e4 LT |
2439 | if (local_flags & __GFP_WAIT) |
2440 | local_irq_disable(); | |
2441 | return 0; | |
2442 | } | |
2443 | ||
2444 | #if DEBUG | |
2445 | ||
2446 | /* | |
2447 | * Perform extra freeing checks: | |
2448 | * - detect bad pointers. | |
2449 | * - POISON/RED_ZONE checking | |
2450 | * - destructor calls, for caches with POISON+dtor | |
2451 | */ | |
2452 | static void kfree_debugcheck(const void *objp) | |
2453 | { | |
2454 | struct page *page; | |
2455 | ||
2456 | if (!virt_addr_valid(objp)) { | |
2457 | printk(KERN_ERR "kfree_debugcheck: out of range ptr %lxh.\n", | |
b28a02de PE |
2458 | (unsigned long)objp); |
2459 | BUG(); | |
1da177e4 LT |
2460 | } |
2461 | page = virt_to_page(objp); | |
2462 | if (!PageSlab(page)) { | |
b28a02de PE |
2463 | printk(KERN_ERR "kfree_debugcheck: bad ptr %lxh.\n", |
2464 | (unsigned long)objp); | |
1da177e4 LT |
2465 | BUG(); |
2466 | } | |
2467 | } | |
2468 | ||
343e0d7a | 2469 | static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp, |
b28a02de | 2470 | void *caller) |
1da177e4 LT |
2471 | { |
2472 | struct page *page; | |
2473 | unsigned int objnr; | |
2474 | struct slab *slabp; | |
2475 | ||
3dafccf2 | 2476 | objp -= obj_offset(cachep); |
1da177e4 LT |
2477 | kfree_debugcheck(objp); |
2478 | page = virt_to_page(objp); | |
2479 | ||
065d41cb | 2480 | if (page_get_cache(page) != cachep) { |
b28a02de PE |
2481 | printk(KERN_ERR |
2482 | "mismatch in kmem_cache_free: expected cache %p, got %p\n", | |
2483 | page_get_cache(page), cachep); | |
1da177e4 | 2484 | printk(KERN_ERR "%p is %s.\n", cachep, cachep->name); |
b28a02de PE |
2485 | printk(KERN_ERR "%p is %s.\n", page_get_cache(page), |
2486 | page_get_cache(page)->name); | |
1da177e4 LT |
2487 | WARN_ON(1); |
2488 | } | |
065d41cb | 2489 | slabp = page_get_slab(page); |
1da177e4 LT |
2490 | |
2491 | if (cachep->flags & SLAB_RED_ZONE) { | |
b28a02de PE |
2492 | if (*dbg_redzone1(cachep, objp) != RED_ACTIVE |
2493 | || *dbg_redzone2(cachep, objp) != RED_ACTIVE) { | |
2494 | slab_error(cachep, | |
2495 | "double free, or memory outside" | |
2496 | " object was overwritten"); | |
2497 | printk(KERN_ERR | |
2498 | "%p: redzone 1: 0x%lx, redzone 2: 0x%lx.\n", | |
2499 | objp, *dbg_redzone1(cachep, objp), | |
2500 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
2501 | } |
2502 | *dbg_redzone1(cachep, objp) = RED_INACTIVE; | |
2503 | *dbg_redzone2(cachep, objp) = RED_INACTIVE; | |
2504 | } | |
2505 | if (cachep->flags & SLAB_STORE_USER) | |
2506 | *dbg_userword(cachep, objp) = caller; | |
2507 | ||
3dafccf2 | 2508 | objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size; |
1da177e4 LT |
2509 | |
2510 | BUG_ON(objnr >= cachep->num); | |
3dafccf2 | 2511 | BUG_ON(objp != slabp->s_mem + objnr * cachep->buffer_size); |
1da177e4 LT |
2512 | |
2513 | if (cachep->flags & SLAB_DEBUG_INITIAL) { | |
2514 | /* Need to call the slab's constructor so the | |
2515 | * caller can perform a verify of its state (debugging). | |
2516 | * Called without the cache-lock held. | |
2517 | */ | |
3dafccf2 | 2518 | cachep->ctor(objp + obj_offset(cachep), |
b28a02de | 2519 | cachep, SLAB_CTOR_CONSTRUCTOR | SLAB_CTOR_VERIFY); |
1da177e4 LT |
2520 | } |
2521 | if (cachep->flags & SLAB_POISON && cachep->dtor) { | |
2522 | /* we want to cache poison the object, | |
2523 | * call the destruction callback | |
2524 | */ | |
3dafccf2 | 2525 | cachep->dtor(objp + obj_offset(cachep), cachep, 0); |
1da177e4 LT |
2526 | } |
2527 | if (cachep->flags & SLAB_POISON) { | |
2528 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
3dafccf2 | 2529 | if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) { |
1da177e4 | 2530 | store_stackinfo(cachep, objp, (unsigned long)caller); |
b28a02de | 2531 | kernel_map_pages(virt_to_page(objp), |
3dafccf2 | 2532 | cachep->buffer_size / PAGE_SIZE, 0); |
1da177e4 LT |
2533 | } else { |
2534 | poison_obj(cachep, objp, POISON_FREE); | |
2535 | } | |
2536 | #else | |
2537 | poison_obj(cachep, objp, POISON_FREE); | |
2538 | #endif | |
2539 | } | |
2540 | return objp; | |
2541 | } | |
2542 | ||
343e0d7a | 2543 | static void check_slabp(struct kmem_cache *cachep, struct slab *slabp) |
1da177e4 LT |
2544 | { |
2545 | kmem_bufctl_t i; | |
2546 | int entries = 0; | |
b28a02de | 2547 | |
1da177e4 LT |
2548 | /* Check slab's freelist to see if this obj is there. */ |
2549 | for (i = slabp->free; i != BUFCTL_END; i = slab_bufctl(slabp)[i]) { | |
2550 | entries++; | |
2551 | if (entries > cachep->num || i >= cachep->num) | |
2552 | goto bad; | |
2553 | } | |
2554 | if (entries != cachep->num - slabp->inuse) { | |
b28a02de PE |
2555 | bad: |
2556 | printk(KERN_ERR | |
2557 | "slab: Internal list corruption detected in cache '%s'(%d), slabp %p(%d). Hexdump:\n", | |
2558 | cachep->name, cachep->num, slabp, slabp->inuse); | |
2559 | for (i = 0; | |
264132bc | 2560 | i < sizeof(*slabp) + cachep->num * sizeof(kmem_bufctl_t); |
b28a02de PE |
2561 | i++) { |
2562 | if ((i % 16) == 0) | |
1da177e4 | 2563 | printk("\n%03x:", i); |
b28a02de | 2564 | printk(" %02x", ((unsigned char *)slabp)[i]); |
1da177e4 LT |
2565 | } |
2566 | printk("\n"); | |
2567 | BUG(); | |
2568 | } | |
2569 | } | |
2570 | #else | |
2571 | #define kfree_debugcheck(x) do { } while(0) | |
2572 | #define cache_free_debugcheck(x,objp,z) (objp) | |
2573 | #define check_slabp(x,y) do { } while(0) | |
2574 | #endif | |
2575 | ||
343e0d7a | 2576 | static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 LT |
2577 | { |
2578 | int batchcount; | |
2579 | struct kmem_list3 *l3; | |
2580 | struct array_cache *ac; | |
2581 | ||
2582 | check_irq_off(); | |
9a2dba4b | 2583 | ac = cpu_cache_get(cachep); |
b28a02de | 2584 | retry: |
1da177e4 LT |
2585 | batchcount = ac->batchcount; |
2586 | if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { | |
2587 | /* if there was little recent activity on this | |
2588 | * cache, then perform only a partial refill. | |
2589 | * Otherwise we could generate refill bouncing. | |
2590 | */ | |
2591 | batchcount = BATCHREFILL_LIMIT; | |
2592 | } | |
e498be7d CL |
2593 | l3 = cachep->nodelists[numa_node_id()]; |
2594 | ||
2595 | BUG_ON(ac->avail > 0 || !l3); | |
2596 | spin_lock(&l3->list_lock); | |
1da177e4 | 2597 | |
1da177e4 LT |
2598 | if (l3->shared) { |
2599 | struct array_cache *shared_array = l3->shared; | |
2600 | if (shared_array->avail) { | |
2601 | if (batchcount > shared_array->avail) | |
2602 | batchcount = shared_array->avail; | |
2603 | shared_array->avail -= batchcount; | |
2604 | ac->avail = batchcount; | |
e498be7d | 2605 | memcpy(ac->entry, |
b28a02de PE |
2606 | &(shared_array->entry[shared_array->avail]), |
2607 | sizeof(void *) * batchcount); | |
1da177e4 LT |
2608 | shared_array->touched = 1; |
2609 | goto alloc_done; | |
2610 | } | |
2611 | } | |
2612 | while (batchcount > 0) { | |
2613 | struct list_head *entry; | |
2614 | struct slab *slabp; | |
2615 | /* Get slab alloc is to come from. */ | |
2616 | entry = l3->slabs_partial.next; | |
2617 | if (entry == &l3->slabs_partial) { | |
2618 | l3->free_touched = 1; | |
2619 | entry = l3->slabs_free.next; | |
2620 | if (entry == &l3->slabs_free) | |
2621 | goto must_grow; | |
2622 | } | |
2623 | ||
2624 | slabp = list_entry(entry, struct slab, list); | |
2625 | check_slabp(cachep, slabp); | |
2626 | check_spinlock_acquired(cachep); | |
2627 | while (slabp->inuse < cachep->num && batchcount--) { | |
1da177e4 LT |
2628 | STATS_INC_ALLOCED(cachep); |
2629 | STATS_INC_ACTIVE(cachep); | |
2630 | STATS_SET_HIGH(cachep); | |
2631 | ||
78d382d7 MD |
2632 | ac->entry[ac->avail++] = slab_get_obj(cachep, slabp, |
2633 | numa_node_id()); | |
1da177e4 LT |
2634 | } |
2635 | check_slabp(cachep, slabp); | |
2636 | ||
2637 | /* move slabp to correct slabp list: */ | |
2638 | list_del(&slabp->list); | |
2639 | if (slabp->free == BUFCTL_END) | |
2640 | list_add(&slabp->list, &l3->slabs_full); | |
2641 | else | |
2642 | list_add(&slabp->list, &l3->slabs_partial); | |
2643 | } | |
2644 | ||
b28a02de | 2645 | must_grow: |
1da177e4 | 2646 | l3->free_objects -= ac->avail; |
b28a02de | 2647 | alloc_done: |
e498be7d | 2648 | spin_unlock(&l3->list_lock); |
1da177e4 LT |
2649 | |
2650 | if (unlikely(!ac->avail)) { | |
2651 | int x; | |
e498be7d CL |
2652 | x = cache_grow(cachep, flags, numa_node_id()); |
2653 | ||
1da177e4 | 2654 | // cache_grow can reenable interrupts, then ac could change. |
9a2dba4b | 2655 | ac = cpu_cache_get(cachep); |
1da177e4 LT |
2656 | if (!x && ac->avail == 0) // no objects in sight? abort |
2657 | return NULL; | |
2658 | ||
b28a02de | 2659 | if (!ac->avail) // objects refilled by interrupt? |
1da177e4 LT |
2660 | goto retry; |
2661 | } | |
2662 | ac->touched = 1; | |
e498be7d | 2663 | return ac->entry[--ac->avail]; |
1da177e4 LT |
2664 | } |
2665 | ||
2666 | static inline void | |
343e0d7a | 2667 | cache_alloc_debugcheck_before(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 LT |
2668 | { |
2669 | might_sleep_if(flags & __GFP_WAIT); | |
2670 | #if DEBUG | |
2671 | kmem_flagcheck(cachep, flags); | |
2672 | #endif | |
2673 | } | |
2674 | ||
2675 | #if DEBUG | |
343e0d7a | 2676 | static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep, gfp_t flags, |
b28a02de | 2677 | void *objp, void *caller) |
1da177e4 | 2678 | { |
b28a02de | 2679 | if (!objp) |
1da177e4 | 2680 | return objp; |
b28a02de | 2681 | if (cachep->flags & SLAB_POISON) { |
1da177e4 | 2682 | #ifdef CONFIG_DEBUG_PAGEALLOC |
3dafccf2 | 2683 | if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) |
b28a02de | 2684 | kernel_map_pages(virt_to_page(objp), |
3dafccf2 | 2685 | cachep->buffer_size / PAGE_SIZE, 1); |
1da177e4 LT |
2686 | else |
2687 | check_poison_obj(cachep, objp); | |
2688 | #else | |
2689 | check_poison_obj(cachep, objp); | |
2690 | #endif | |
2691 | poison_obj(cachep, objp, POISON_INUSE); | |
2692 | } | |
2693 | if (cachep->flags & SLAB_STORE_USER) | |
2694 | *dbg_userword(cachep, objp) = caller; | |
2695 | ||
2696 | if (cachep->flags & SLAB_RED_ZONE) { | |
b28a02de PE |
2697 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE |
2698 | || *dbg_redzone2(cachep, objp) != RED_INACTIVE) { | |
2699 | slab_error(cachep, | |
2700 | "double free, or memory outside" | |
2701 | " object was overwritten"); | |
2702 | printk(KERN_ERR | |
2703 | "%p: redzone 1: 0x%lx, redzone 2: 0x%lx.\n", | |
2704 | objp, *dbg_redzone1(cachep, objp), | |
2705 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
2706 | } |
2707 | *dbg_redzone1(cachep, objp) = RED_ACTIVE; | |
2708 | *dbg_redzone2(cachep, objp) = RED_ACTIVE; | |
2709 | } | |
3dafccf2 | 2710 | objp += obj_offset(cachep); |
1da177e4 | 2711 | if (cachep->ctor && cachep->flags & SLAB_POISON) { |
b28a02de | 2712 | unsigned long ctor_flags = SLAB_CTOR_CONSTRUCTOR; |
1da177e4 LT |
2713 | |
2714 | if (!(flags & __GFP_WAIT)) | |
2715 | ctor_flags |= SLAB_CTOR_ATOMIC; | |
2716 | ||
2717 | cachep->ctor(objp, cachep, ctor_flags); | |
b28a02de | 2718 | } |
1da177e4 LT |
2719 | return objp; |
2720 | } | |
2721 | #else | |
2722 | #define cache_alloc_debugcheck_after(a,b,objp,d) (objp) | |
2723 | #endif | |
2724 | ||
343e0d7a | 2725 | static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 | 2726 | { |
b28a02de | 2727 | void *objp; |
1da177e4 LT |
2728 | struct array_cache *ac; |
2729 | ||
dc85da15 | 2730 | #ifdef CONFIG_NUMA |
86c562a9 | 2731 | if (unlikely(current->mempolicy && !in_interrupt())) { |
dc85da15 CL |
2732 | int nid = slab_node(current->mempolicy); |
2733 | ||
2734 | if (nid != numa_node_id()) | |
2735 | return __cache_alloc_node(cachep, flags, nid); | |
2736 | } | |
2737 | #endif | |
2738 | ||
5c382300 | 2739 | check_irq_off(); |
9a2dba4b | 2740 | ac = cpu_cache_get(cachep); |
1da177e4 LT |
2741 | if (likely(ac->avail)) { |
2742 | STATS_INC_ALLOCHIT(cachep); | |
2743 | ac->touched = 1; | |
e498be7d | 2744 | objp = ac->entry[--ac->avail]; |
1da177e4 LT |
2745 | } else { |
2746 | STATS_INC_ALLOCMISS(cachep); | |
2747 | objp = cache_alloc_refill(cachep, flags); | |
2748 | } | |
5c382300 AK |
2749 | return objp; |
2750 | } | |
2751 | ||
7fd6b141 PE |
2752 | static __always_inline void * |
2753 | __cache_alloc(struct kmem_cache *cachep, gfp_t flags, void *caller) | |
5c382300 AK |
2754 | { |
2755 | unsigned long save_flags; | |
b28a02de | 2756 | void *objp; |
5c382300 AK |
2757 | |
2758 | cache_alloc_debugcheck_before(cachep, flags); | |
2759 | ||
2760 | local_irq_save(save_flags); | |
2761 | objp = ____cache_alloc(cachep, flags); | |
1da177e4 | 2762 | local_irq_restore(save_flags); |
34342e86 | 2763 | objp = cache_alloc_debugcheck_after(cachep, flags, objp, |
7fd6b141 | 2764 | caller); |
34342e86 | 2765 | prefetchw(objp); |
1da177e4 LT |
2766 | return objp; |
2767 | } | |
2768 | ||
e498be7d CL |
2769 | #ifdef CONFIG_NUMA |
2770 | /* | |
2771 | * A interface to enable slab creation on nodeid | |
1da177e4 | 2772 | */ |
343e0d7a | 2773 | static void *__cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
e498be7d CL |
2774 | { |
2775 | struct list_head *entry; | |
b28a02de PE |
2776 | struct slab *slabp; |
2777 | struct kmem_list3 *l3; | |
2778 | void *obj; | |
b28a02de PE |
2779 | int x; |
2780 | ||
2781 | l3 = cachep->nodelists[nodeid]; | |
2782 | BUG_ON(!l3); | |
2783 | ||
2784 | retry: | |
ca3b9b91 | 2785 | check_irq_off(); |
b28a02de PE |
2786 | spin_lock(&l3->list_lock); |
2787 | entry = l3->slabs_partial.next; | |
2788 | if (entry == &l3->slabs_partial) { | |
2789 | l3->free_touched = 1; | |
2790 | entry = l3->slabs_free.next; | |
2791 | if (entry == &l3->slabs_free) | |
2792 | goto must_grow; | |
2793 | } | |
2794 | ||
2795 | slabp = list_entry(entry, struct slab, list); | |
2796 | check_spinlock_acquired_node(cachep, nodeid); | |
2797 | check_slabp(cachep, slabp); | |
2798 | ||
2799 | STATS_INC_NODEALLOCS(cachep); | |
2800 | STATS_INC_ACTIVE(cachep); | |
2801 | STATS_SET_HIGH(cachep); | |
2802 | ||
2803 | BUG_ON(slabp->inuse == cachep->num); | |
2804 | ||
78d382d7 | 2805 | obj = slab_get_obj(cachep, slabp, nodeid); |
b28a02de PE |
2806 | check_slabp(cachep, slabp); |
2807 | l3->free_objects--; | |
2808 | /* move slabp to correct slabp list: */ | |
2809 | list_del(&slabp->list); | |
2810 | ||
2811 | if (slabp->free == BUFCTL_END) { | |
2812 | list_add(&slabp->list, &l3->slabs_full); | |
2813 | } else { | |
2814 | list_add(&slabp->list, &l3->slabs_partial); | |
2815 | } | |
e498be7d | 2816 | |
b28a02de PE |
2817 | spin_unlock(&l3->list_lock); |
2818 | goto done; | |
e498be7d | 2819 | |
b28a02de PE |
2820 | must_grow: |
2821 | spin_unlock(&l3->list_lock); | |
2822 | x = cache_grow(cachep, flags, nodeid); | |
1da177e4 | 2823 | |
b28a02de PE |
2824 | if (!x) |
2825 | return NULL; | |
e498be7d | 2826 | |
b28a02de PE |
2827 | goto retry; |
2828 | done: | |
2829 | return obj; | |
e498be7d CL |
2830 | } |
2831 | #endif | |
2832 | ||
2833 | /* | |
2834 | * Caller needs to acquire correct kmem_list's list_lock | |
2835 | */ | |
343e0d7a | 2836 | static void free_block(struct kmem_cache *cachep, void **objpp, int nr_objects, |
b28a02de | 2837 | int node) |
1da177e4 LT |
2838 | { |
2839 | int i; | |
e498be7d | 2840 | struct kmem_list3 *l3; |
1da177e4 LT |
2841 | |
2842 | for (i = 0; i < nr_objects; i++) { | |
2843 | void *objp = objpp[i]; | |
2844 | struct slab *slabp; | |
1da177e4 | 2845 | |
6ed5eb22 | 2846 | slabp = virt_to_slab(objp); |
ff69416e | 2847 | l3 = cachep->nodelists[node]; |
1da177e4 | 2848 | list_del(&slabp->list); |
ff69416e | 2849 | check_spinlock_acquired_node(cachep, node); |
1da177e4 | 2850 | check_slabp(cachep, slabp); |
78d382d7 | 2851 | slab_put_obj(cachep, slabp, objp, node); |
1da177e4 | 2852 | STATS_DEC_ACTIVE(cachep); |
e498be7d | 2853 | l3->free_objects++; |
1da177e4 LT |
2854 | check_slabp(cachep, slabp); |
2855 | ||
2856 | /* fixup slab chains */ | |
2857 | if (slabp->inuse == 0) { | |
e498be7d CL |
2858 | if (l3->free_objects > l3->free_limit) { |
2859 | l3->free_objects -= cachep->num; | |
1da177e4 LT |
2860 | slab_destroy(cachep, slabp); |
2861 | } else { | |
e498be7d | 2862 | list_add(&slabp->list, &l3->slabs_free); |
1da177e4 LT |
2863 | } |
2864 | } else { | |
2865 | /* Unconditionally move a slab to the end of the | |
2866 | * partial list on free - maximum time for the | |
2867 | * other objects to be freed, too. | |
2868 | */ | |
e498be7d | 2869 | list_add_tail(&slabp->list, &l3->slabs_partial); |
1da177e4 LT |
2870 | } |
2871 | } | |
2872 | } | |
2873 | ||
343e0d7a | 2874 | static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac) |
1da177e4 LT |
2875 | { |
2876 | int batchcount; | |
e498be7d | 2877 | struct kmem_list3 *l3; |
ff69416e | 2878 | int node = numa_node_id(); |
1da177e4 LT |
2879 | |
2880 | batchcount = ac->batchcount; | |
2881 | #if DEBUG | |
2882 | BUG_ON(!batchcount || batchcount > ac->avail); | |
2883 | #endif | |
2884 | check_irq_off(); | |
ff69416e | 2885 | l3 = cachep->nodelists[node]; |
e498be7d CL |
2886 | spin_lock(&l3->list_lock); |
2887 | if (l3->shared) { | |
2888 | struct array_cache *shared_array = l3->shared; | |
b28a02de | 2889 | int max = shared_array->limit - shared_array->avail; |
1da177e4 LT |
2890 | if (max) { |
2891 | if (batchcount > max) | |
2892 | batchcount = max; | |
e498be7d | 2893 | memcpy(&(shared_array->entry[shared_array->avail]), |
b28a02de | 2894 | ac->entry, sizeof(void *) * batchcount); |
1da177e4 LT |
2895 | shared_array->avail += batchcount; |
2896 | goto free_done; | |
2897 | } | |
2898 | } | |
2899 | ||
ff69416e | 2900 | free_block(cachep, ac->entry, batchcount, node); |
b28a02de | 2901 | free_done: |
1da177e4 LT |
2902 | #if STATS |
2903 | { | |
2904 | int i = 0; | |
2905 | struct list_head *p; | |
2906 | ||
e498be7d CL |
2907 | p = l3->slabs_free.next; |
2908 | while (p != &(l3->slabs_free)) { | |
1da177e4 LT |
2909 | struct slab *slabp; |
2910 | ||
2911 | slabp = list_entry(p, struct slab, list); | |
2912 | BUG_ON(slabp->inuse); | |
2913 | ||
2914 | i++; | |
2915 | p = p->next; | |
2916 | } | |
2917 | STATS_SET_FREEABLE(cachep, i); | |
2918 | } | |
2919 | #endif | |
e498be7d | 2920 | spin_unlock(&l3->list_lock); |
1da177e4 | 2921 | ac->avail -= batchcount; |
e498be7d | 2922 | memmove(ac->entry, &(ac->entry[batchcount]), |
b28a02de | 2923 | sizeof(void *) * ac->avail); |
1da177e4 LT |
2924 | } |
2925 | ||
2926 | /* | |
2927 | * __cache_free | |
2928 | * Release an obj back to its cache. If the obj has a constructed | |
2929 | * state, it must be in this state _before_ it is released. | |
2930 | * | |
2931 | * Called with disabled ints. | |
2932 | */ | |
343e0d7a | 2933 | static inline void __cache_free(struct kmem_cache *cachep, void *objp) |
1da177e4 | 2934 | { |
9a2dba4b | 2935 | struct array_cache *ac = cpu_cache_get(cachep); |
1da177e4 LT |
2936 | |
2937 | check_irq_off(); | |
2938 | objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0)); | |
2939 | ||
e498be7d CL |
2940 | /* Make sure we are not freeing a object from another |
2941 | * node to the array cache on this cpu. | |
2942 | */ | |
2943 | #ifdef CONFIG_NUMA | |
2944 | { | |
2945 | struct slab *slabp; | |
6ed5eb22 | 2946 | slabp = virt_to_slab(objp); |
e498be7d CL |
2947 | if (unlikely(slabp->nodeid != numa_node_id())) { |
2948 | struct array_cache *alien = NULL; | |
2949 | int nodeid = slabp->nodeid; | |
b28a02de PE |
2950 | struct kmem_list3 *l3 = |
2951 | cachep->nodelists[numa_node_id()]; | |
e498be7d CL |
2952 | |
2953 | STATS_INC_NODEFREES(cachep); | |
2954 | if (l3->alien && l3->alien[nodeid]) { | |
2955 | alien = l3->alien[nodeid]; | |
2956 | spin_lock(&alien->lock); | |
2957 | if (unlikely(alien->avail == alien->limit)) | |
2958 | __drain_alien_cache(cachep, | |
b28a02de | 2959 | alien, nodeid); |
e498be7d CL |
2960 | alien->entry[alien->avail++] = objp; |
2961 | spin_unlock(&alien->lock); | |
2962 | } else { | |
2963 | spin_lock(&(cachep->nodelists[nodeid])-> | |
b28a02de | 2964 | list_lock); |
ff69416e | 2965 | free_block(cachep, &objp, 1, nodeid); |
e498be7d | 2966 | spin_unlock(&(cachep->nodelists[nodeid])-> |
b28a02de | 2967 | list_lock); |
e498be7d CL |
2968 | } |
2969 | return; | |
2970 | } | |
2971 | } | |
2972 | #endif | |
1da177e4 LT |
2973 | if (likely(ac->avail < ac->limit)) { |
2974 | STATS_INC_FREEHIT(cachep); | |
e498be7d | 2975 | ac->entry[ac->avail++] = objp; |
1da177e4 LT |
2976 | return; |
2977 | } else { | |
2978 | STATS_INC_FREEMISS(cachep); | |
2979 | cache_flusharray(cachep, ac); | |
e498be7d | 2980 | ac->entry[ac->avail++] = objp; |
1da177e4 LT |
2981 | } |
2982 | } | |
2983 | ||
2984 | /** | |
2985 | * kmem_cache_alloc - Allocate an object | |
2986 | * @cachep: The cache to allocate from. | |
2987 | * @flags: See kmalloc(). | |
2988 | * | |
2989 | * Allocate an object from this cache. The flags are only relevant | |
2990 | * if the cache has no available objects. | |
2991 | */ | |
343e0d7a | 2992 | void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags) |
1da177e4 | 2993 | { |
7fd6b141 | 2994 | return __cache_alloc(cachep, flags, __builtin_return_address(0)); |
1da177e4 LT |
2995 | } |
2996 | EXPORT_SYMBOL(kmem_cache_alloc); | |
2997 | ||
2998 | /** | |
2999 | * kmem_ptr_validate - check if an untrusted pointer might | |
3000 | * be a slab entry. | |
3001 | * @cachep: the cache we're checking against | |
3002 | * @ptr: pointer to validate | |
3003 | * | |
3004 | * This verifies that the untrusted pointer looks sane: | |
3005 | * it is _not_ a guarantee that the pointer is actually | |
3006 | * part of the slab cache in question, but it at least | |
3007 | * validates that the pointer can be dereferenced and | |
3008 | * looks half-way sane. | |
3009 | * | |
3010 | * Currently only used for dentry validation. | |
3011 | */ | |
343e0d7a | 3012 | int fastcall kmem_ptr_validate(struct kmem_cache *cachep, void *ptr) |
1da177e4 | 3013 | { |
b28a02de | 3014 | unsigned long addr = (unsigned long)ptr; |
1da177e4 | 3015 | unsigned long min_addr = PAGE_OFFSET; |
b28a02de | 3016 | unsigned long align_mask = BYTES_PER_WORD - 1; |
3dafccf2 | 3017 | unsigned long size = cachep->buffer_size; |
1da177e4 LT |
3018 | struct page *page; |
3019 | ||
3020 | if (unlikely(addr < min_addr)) | |
3021 | goto out; | |
3022 | if (unlikely(addr > (unsigned long)high_memory - size)) | |
3023 | goto out; | |
3024 | if (unlikely(addr & align_mask)) | |
3025 | goto out; | |
3026 | if (unlikely(!kern_addr_valid(addr))) | |
3027 | goto out; | |
3028 | if (unlikely(!kern_addr_valid(addr + size - 1))) | |
3029 | goto out; | |
3030 | page = virt_to_page(ptr); | |
3031 | if (unlikely(!PageSlab(page))) | |
3032 | goto out; | |
065d41cb | 3033 | if (unlikely(page_get_cache(page) != cachep)) |
1da177e4 LT |
3034 | goto out; |
3035 | return 1; | |
b28a02de | 3036 | out: |
1da177e4 LT |
3037 | return 0; |
3038 | } | |
3039 | ||
3040 | #ifdef CONFIG_NUMA | |
3041 | /** | |
3042 | * kmem_cache_alloc_node - Allocate an object on the specified node | |
3043 | * @cachep: The cache to allocate from. | |
3044 | * @flags: See kmalloc(). | |
3045 | * @nodeid: node number of the target node. | |
3046 | * | |
3047 | * Identical to kmem_cache_alloc, except that this function is slow | |
3048 | * and can sleep. And it will allocate memory on the given node, which | |
3049 | * can improve the performance for cpu bound structures. | |
e498be7d CL |
3050 | * New and improved: it will now make sure that the object gets |
3051 | * put on the correct node list so that there is no false sharing. | |
1da177e4 | 3052 | */ |
343e0d7a | 3053 | void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid) |
1da177e4 | 3054 | { |
e498be7d CL |
3055 | unsigned long save_flags; |
3056 | void *ptr; | |
1da177e4 | 3057 | |
e498be7d CL |
3058 | cache_alloc_debugcheck_before(cachep, flags); |
3059 | local_irq_save(save_flags); | |
18f820f6 CL |
3060 | |
3061 | if (nodeid == -1 || nodeid == numa_node_id() || | |
3062 | !cachep->nodelists[nodeid]) | |
5c382300 AK |
3063 | ptr = ____cache_alloc(cachep, flags); |
3064 | else | |
3065 | ptr = __cache_alloc_node(cachep, flags, nodeid); | |
e498be7d | 3066 | local_irq_restore(save_flags); |
18f820f6 CL |
3067 | |
3068 | ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, | |
3069 | __builtin_return_address(0)); | |
1da177e4 | 3070 | |
e498be7d | 3071 | return ptr; |
1da177e4 LT |
3072 | } |
3073 | EXPORT_SYMBOL(kmem_cache_alloc_node); | |
3074 | ||
dd0fc66f | 3075 | void *kmalloc_node(size_t size, gfp_t flags, int node) |
97e2bde4 | 3076 | { |
343e0d7a | 3077 | struct kmem_cache *cachep; |
97e2bde4 MS |
3078 | |
3079 | cachep = kmem_find_general_cachep(size, flags); | |
3080 | if (unlikely(cachep == NULL)) | |
3081 | return NULL; | |
3082 | return kmem_cache_alloc_node(cachep, flags, node); | |
3083 | } | |
3084 | EXPORT_SYMBOL(kmalloc_node); | |
1da177e4 LT |
3085 | #endif |
3086 | ||
3087 | /** | |
3088 | * kmalloc - allocate memory | |
3089 | * @size: how many bytes of memory are required. | |
3090 | * @flags: the type of memory to allocate. | |
3091 | * | |
3092 | * kmalloc is the normal method of allocating memory | |
3093 | * in the kernel. | |
3094 | * | |
3095 | * The @flags argument may be one of: | |
3096 | * | |
3097 | * %GFP_USER - Allocate memory on behalf of user. May sleep. | |
3098 | * | |
3099 | * %GFP_KERNEL - Allocate normal kernel ram. May sleep. | |
3100 | * | |
3101 | * %GFP_ATOMIC - Allocation will not sleep. Use inside interrupt handlers. | |
3102 | * | |
3103 | * Additionally, the %GFP_DMA flag may be set to indicate the memory | |
3104 | * must be suitable for DMA. This can mean different things on different | |
3105 | * platforms. For example, on i386, it means that the memory must come | |
3106 | * from the first 16MB. | |
3107 | */ | |
7fd6b141 PE |
3108 | static __always_inline void *__do_kmalloc(size_t size, gfp_t flags, |
3109 | void *caller) | |
1da177e4 | 3110 | { |
343e0d7a | 3111 | struct kmem_cache *cachep; |
1da177e4 | 3112 | |
97e2bde4 MS |
3113 | /* If you want to save a few bytes .text space: replace |
3114 | * __ with kmem_. | |
3115 | * Then kmalloc uses the uninlined functions instead of the inline | |
3116 | * functions. | |
3117 | */ | |
3118 | cachep = __find_general_cachep(size, flags); | |
dbdb9045 AM |
3119 | if (unlikely(cachep == NULL)) |
3120 | return NULL; | |
7fd6b141 PE |
3121 | return __cache_alloc(cachep, flags, caller); |
3122 | } | |
3123 | ||
3124 | #ifndef CONFIG_DEBUG_SLAB | |
3125 | ||
3126 | void *__kmalloc(size_t size, gfp_t flags) | |
3127 | { | |
3128 | return __do_kmalloc(size, flags, NULL); | |
1da177e4 LT |
3129 | } |
3130 | EXPORT_SYMBOL(__kmalloc); | |
3131 | ||
7fd6b141 PE |
3132 | #else |
3133 | ||
3134 | void *__kmalloc_track_caller(size_t size, gfp_t flags, void *caller) | |
3135 | { | |
3136 | return __do_kmalloc(size, flags, caller); | |
3137 | } | |
3138 | EXPORT_SYMBOL(__kmalloc_track_caller); | |
3139 | ||
3140 | #endif | |
3141 | ||
1da177e4 LT |
3142 | #ifdef CONFIG_SMP |
3143 | /** | |
3144 | * __alloc_percpu - allocate one copy of the object for every present | |
3145 | * cpu in the system, zeroing them. | |
3146 | * Objects should be dereferenced using the per_cpu_ptr macro only. | |
3147 | * | |
3148 | * @size: how many bytes of memory are required. | |
1da177e4 | 3149 | */ |
f9f75005 | 3150 | void *__alloc_percpu(size_t size) |
1da177e4 LT |
3151 | { |
3152 | int i; | |
b28a02de | 3153 | struct percpu_data *pdata = kmalloc(sizeof(*pdata), GFP_KERNEL); |
1da177e4 LT |
3154 | |
3155 | if (!pdata) | |
3156 | return NULL; | |
3157 | ||
e498be7d CL |
3158 | /* |
3159 | * Cannot use for_each_online_cpu since a cpu may come online | |
3160 | * and we have no way of figuring out how to fix the array | |
3161 | * that we have allocated then.... | |
3162 | */ | |
3163 | for_each_cpu(i) { | |
3164 | int node = cpu_to_node(i); | |
3165 | ||
3166 | if (node_online(node)) | |
3167 | pdata->ptrs[i] = kmalloc_node(size, GFP_KERNEL, node); | |
3168 | else | |
3169 | pdata->ptrs[i] = kmalloc(size, GFP_KERNEL); | |
1da177e4 LT |
3170 | |
3171 | if (!pdata->ptrs[i]) | |
3172 | goto unwind_oom; | |
3173 | memset(pdata->ptrs[i], 0, size); | |
3174 | } | |
3175 | ||
3176 | /* Catch derefs w/o wrappers */ | |
b28a02de | 3177 | return (void *)(~(unsigned long)pdata); |
1da177e4 | 3178 | |
b28a02de | 3179 | unwind_oom: |
1da177e4 LT |
3180 | while (--i >= 0) { |
3181 | if (!cpu_possible(i)) | |
3182 | continue; | |
3183 | kfree(pdata->ptrs[i]); | |
3184 | } | |
3185 | kfree(pdata); | |
3186 | return NULL; | |
3187 | } | |
3188 | EXPORT_SYMBOL(__alloc_percpu); | |
3189 | #endif | |
3190 | ||
3191 | /** | |
3192 | * kmem_cache_free - Deallocate an object | |
3193 | * @cachep: The cache the allocation was from. | |
3194 | * @objp: The previously allocated object. | |
3195 | * | |
3196 | * Free an object which was previously allocated from this | |
3197 | * cache. | |
3198 | */ | |
343e0d7a | 3199 | void kmem_cache_free(struct kmem_cache *cachep, void *objp) |
1da177e4 LT |
3200 | { |
3201 | unsigned long flags; | |
3202 | ||
3203 | local_irq_save(flags); | |
3204 | __cache_free(cachep, objp); | |
3205 | local_irq_restore(flags); | |
3206 | } | |
3207 | EXPORT_SYMBOL(kmem_cache_free); | |
3208 | ||
1da177e4 LT |
3209 | /** |
3210 | * kfree - free previously allocated memory | |
3211 | * @objp: pointer returned by kmalloc. | |
3212 | * | |
80e93eff PE |
3213 | * If @objp is NULL, no operation is performed. |
3214 | * | |
1da177e4 LT |
3215 | * Don't free memory not originally allocated by kmalloc() |
3216 | * or you will run into trouble. | |
3217 | */ | |
3218 | void kfree(const void *objp) | |
3219 | { | |
343e0d7a | 3220 | struct kmem_cache *c; |
1da177e4 LT |
3221 | unsigned long flags; |
3222 | ||
3223 | if (unlikely(!objp)) | |
3224 | return; | |
3225 | local_irq_save(flags); | |
3226 | kfree_debugcheck(objp); | |
6ed5eb22 | 3227 | c = virt_to_cache(objp); |
3dafccf2 | 3228 | mutex_debug_check_no_locks_freed(objp, obj_size(c)); |
b28a02de | 3229 | __cache_free(c, (void *)objp); |
1da177e4 LT |
3230 | local_irq_restore(flags); |
3231 | } | |
3232 | EXPORT_SYMBOL(kfree); | |
3233 | ||
3234 | #ifdef CONFIG_SMP | |
3235 | /** | |
3236 | * free_percpu - free previously allocated percpu memory | |
3237 | * @objp: pointer returned by alloc_percpu. | |
3238 | * | |
3239 | * Don't free memory not originally allocated by alloc_percpu() | |
3240 | * The complemented objp is to check for that. | |
3241 | */ | |
b28a02de | 3242 | void free_percpu(const void *objp) |
1da177e4 LT |
3243 | { |
3244 | int i; | |
b28a02de | 3245 | struct percpu_data *p = (struct percpu_data *)(~(unsigned long)objp); |
1da177e4 | 3246 | |
e498be7d CL |
3247 | /* |
3248 | * We allocate for all cpus so we cannot use for online cpu here. | |
3249 | */ | |
3250 | for_each_cpu(i) | |
b28a02de | 3251 | kfree(p->ptrs[i]); |
1da177e4 LT |
3252 | kfree(p); |
3253 | } | |
3254 | EXPORT_SYMBOL(free_percpu); | |
3255 | #endif | |
3256 | ||
343e0d7a | 3257 | unsigned int kmem_cache_size(struct kmem_cache *cachep) |
1da177e4 | 3258 | { |
3dafccf2 | 3259 | return obj_size(cachep); |
1da177e4 LT |
3260 | } |
3261 | EXPORT_SYMBOL(kmem_cache_size); | |
3262 | ||
343e0d7a | 3263 | const char *kmem_cache_name(struct kmem_cache *cachep) |
1944972d ACM |
3264 | { |
3265 | return cachep->name; | |
3266 | } | |
3267 | EXPORT_SYMBOL_GPL(kmem_cache_name); | |
3268 | ||
e498be7d CL |
3269 | /* |
3270 | * This initializes kmem_list3 for all nodes. | |
3271 | */ | |
343e0d7a | 3272 | static int alloc_kmemlist(struct kmem_cache *cachep) |
e498be7d CL |
3273 | { |
3274 | int node; | |
3275 | struct kmem_list3 *l3; | |
3276 | int err = 0; | |
3277 | ||
3278 | for_each_online_node(node) { | |
3279 | struct array_cache *nc = NULL, *new; | |
3280 | struct array_cache **new_alien = NULL; | |
3281 | #ifdef CONFIG_NUMA | |
3282 | if (!(new_alien = alloc_alien_cache(node, cachep->limit))) | |
3283 | goto fail; | |
3284 | #endif | |
b28a02de PE |
3285 | if (!(new = alloc_arraycache(node, (cachep->shared * |
3286 | cachep->batchcount), | |
3287 | 0xbaadf00d))) | |
e498be7d CL |
3288 | goto fail; |
3289 | if ((l3 = cachep->nodelists[node])) { | |
3290 | ||
3291 | spin_lock_irq(&l3->list_lock); | |
3292 | ||
3293 | if ((nc = cachep->nodelists[node]->shared)) | |
b28a02de | 3294 | free_block(cachep, nc->entry, nc->avail, node); |
e498be7d CL |
3295 | |
3296 | l3->shared = new; | |
3297 | if (!cachep->nodelists[node]->alien) { | |
3298 | l3->alien = new_alien; | |
3299 | new_alien = NULL; | |
3300 | } | |
b28a02de PE |
3301 | l3->free_limit = (1 + nr_cpus_node(node)) * |
3302 | cachep->batchcount + cachep->num; | |
e498be7d CL |
3303 | spin_unlock_irq(&l3->list_lock); |
3304 | kfree(nc); | |
3305 | free_alien_cache(new_alien); | |
3306 | continue; | |
3307 | } | |
3308 | if (!(l3 = kmalloc_node(sizeof(struct kmem_list3), | |
b28a02de | 3309 | GFP_KERNEL, node))) |
e498be7d CL |
3310 | goto fail; |
3311 | ||
3312 | kmem_list3_init(l3); | |
3313 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + | |
b28a02de | 3314 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
e498be7d CL |
3315 | l3->shared = new; |
3316 | l3->alien = new_alien; | |
b28a02de PE |
3317 | l3->free_limit = (1 + nr_cpus_node(node)) * |
3318 | cachep->batchcount + cachep->num; | |
e498be7d CL |
3319 | cachep->nodelists[node] = l3; |
3320 | } | |
3321 | return err; | |
b28a02de | 3322 | fail: |
e498be7d CL |
3323 | err = -ENOMEM; |
3324 | return err; | |
3325 | } | |
3326 | ||
1da177e4 | 3327 | struct ccupdate_struct { |
343e0d7a | 3328 | struct kmem_cache *cachep; |
1da177e4 LT |
3329 | struct array_cache *new[NR_CPUS]; |
3330 | }; | |
3331 | ||
3332 | static void do_ccupdate_local(void *info) | |
3333 | { | |
3334 | struct ccupdate_struct *new = (struct ccupdate_struct *)info; | |
3335 | struct array_cache *old; | |
3336 | ||
3337 | check_irq_off(); | |
9a2dba4b | 3338 | old = cpu_cache_get(new->cachep); |
e498be7d | 3339 | |
1da177e4 LT |
3340 | new->cachep->array[smp_processor_id()] = new->new[smp_processor_id()]; |
3341 | new->new[smp_processor_id()] = old; | |
3342 | } | |
3343 | ||
343e0d7a | 3344 | static int do_tune_cpucache(struct kmem_cache *cachep, int limit, int batchcount, |
b28a02de | 3345 | int shared) |
1da177e4 LT |
3346 | { |
3347 | struct ccupdate_struct new; | |
e498be7d | 3348 | int i, err; |
1da177e4 | 3349 | |
b28a02de | 3350 | memset(&new.new, 0, sizeof(new.new)); |
e498be7d | 3351 | for_each_online_cpu(i) { |
b28a02de PE |
3352 | new.new[i] = |
3353 | alloc_arraycache(cpu_to_node(i), limit, batchcount); | |
e498be7d | 3354 | if (!new.new[i]) { |
b28a02de PE |
3355 | for (i--; i >= 0; i--) |
3356 | kfree(new.new[i]); | |
e498be7d | 3357 | return -ENOMEM; |
1da177e4 LT |
3358 | } |
3359 | } | |
3360 | new.cachep = cachep; | |
3361 | ||
3362 | smp_call_function_all_cpus(do_ccupdate_local, (void *)&new); | |
e498be7d | 3363 | |
1da177e4 | 3364 | check_irq_on(); |
ca3b9b91 | 3365 | spin_lock(&cachep->spinlock); |
1da177e4 LT |
3366 | cachep->batchcount = batchcount; |
3367 | cachep->limit = limit; | |
e498be7d | 3368 | cachep->shared = shared; |
ca3b9b91 | 3369 | spin_unlock(&cachep->spinlock); |
1da177e4 | 3370 | |
e498be7d | 3371 | for_each_online_cpu(i) { |
1da177e4 LT |
3372 | struct array_cache *ccold = new.new[i]; |
3373 | if (!ccold) | |
3374 | continue; | |
e498be7d | 3375 | spin_lock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
ff69416e | 3376 | free_block(cachep, ccold->entry, ccold->avail, cpu_to_node(i)); |
e498be7d | 3377 | spin_unlock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
1da177e4 LT |
3378 | kfree(ccold); |
3379 | } | |
1da177e4 | 3380 | |
e498be7d CL |
3381 | err = alloc_kmemlist(cachep); |
3382 | if (err) { | |
3383 | printk(KERN_ERR "alloc_kmemlist failed for %s, error %d.\n", | |
b28a02de | 3384 | cachep->name, -err); |
e498be7d | 3385 | BUG(); |
1da177e4 | 3386 | } |
1da177e4 LT |
3387 | return 0; |
3388 | } | |
3389 | ||
343e0d7a | 3390 | static void enable_cpucache(struct kmem_cache *cachep) |
1da177e4 LT |
3391 | { |
3392 | int err; | |
3393 | int limit, shared; | |
3394 | ||
3395 | /* The head array serves three purposes: | |
3396 | * - create a LIFO ordering, i.e. return objects that are cache-warm | |
3397 | * - reduce the number of spinlock operations. | |
3398 | * - reduce the number of linked list operations on the slab and | |
3399 | * bufctl chains: array operations are cheaper. | |
3400 | * The numbers are guessed, we should auto-tune as described by | |
3401 | * Bonwick. | |
3402 | */ | |
3dafccf2 | 3403 | if (cachep->buffer_size > 131072) |
1da177e4 | 3404 | limit = 1; |
3dafccf2 | 3405 | else if (cachep->buffer_size > PAGE_SIZE) |
1da177e4 | 3406 | limit = 8; |
3dafccf2 | 3407 | else if (cachep->buffer_size > 1024) |
1da177e4 | 3408 | limit = 24; |
3dafccf2 | 3409 | else if (cachep->buffer_size > 256) |
1da177e4 LT |
3410 | limit = 54; |
3411 | else | |
3412 | limit = 120; | |
3413 | ||
3414 | /* Cpu bound tasks (e.g. network routing) can exhibit cpu bound | |
3415 | * allocation behaviour: Most allocs on one cpu, most free operations | |
3416 | * on another cpu. For these cases, an efficient object passing between | |
3417 | * cpus is necessary. This is provided by a shared array. The array | |
3418 | * replaces Bonwick's magazine layer. | |
3419 | * On uniprocessor, it's functionally equivalent (but less efficient) | |
3420 | * to a larger limit. Thus disabled by default. | |
3421 | */ | |
3422 | shared = 0; | |
3423 | #ifdef CONFIG_SMP | |
3dafccf2 | 3424 | if (cachep->buffer_size <= PAGE_SIZE) |
1da177e4 LT |
3425 | shared = 8; |
3426 | #endif | |
3427 | ||
3428 | #if DEBUG | |
3429 | /* With debugging enabled, large batchcount lead to excessively | |
3430 | * long periods with disabled local interrupts. Limit the | |
3431 | * batchcount | |
3432 | */ | |
3433 | if (limit > 32) | |
3434 | limit = 32; | |
3435 | #endif | |
b28a02de | 3436 | err = do_tune_cpucache(cachep, limit, (limit + 1) / 2, shared); |
1da177e4 LT |
3437 | if (err) |
3438 | printk(KERN_ERR "enable_cpucache failed for %s, error %d.\n", | |
b28a02de | 3439 | cachep->name, -err); |
1da177e4 LT |
3440 | } |
3441 | ||
343e0d7a | 3442 | static void drain_array_locked(struct kmem_cache *cachep, struct array_cache *ac, |
b28a02de | 3443 | int force, int node) |
1da177e4 LT |
3444 | { |
3445 | int tofree; | |
3446 | ||
e498be7d | 3447 | check_spinlock_acquired_node(cachep, node); |
1da177e4 LT |
3448 | if (ac->touched && !force) { |
3449 | ac->touched = 0; | |
3450 | } else if (ac->avail) { | |
b28a02de | 3451 | tofree = force ? ac->avail : (ac->limit + 4) / 5; |
1da177e4 | 3452 | if (tofree > ac->avail) { |
b28a02de | 3453 | tofree = (ac->avail + 1) / 2; |
1da177e4 | 3454 | } |
ff69416e | 3455 | free_block(cachep, ac->entry, tofree, node); |
1da177e4 | 3456 | ac->avail -= tofree; |
e498be7d | 3457 | memmove(ac->entry, &(ac->entry[tofree]), |
b28a02de | 3458 | sizeof(void *) * ac->avail); |
1da177e4 LT |
3459 | } |
3460 | } | |
3461 | ||
3462 | /** | |
3463 | * cache_reap - Reclaim memory from caches. | |
1e5d5331 | 3464 | * @unused: unused parameter |
1da177e4 LT |
3465 | * |
3466 | * Called from workqueue/eventd every few seconds. | |
3467 | * Purpose: | |
3468 | * - clear the per-cpu caches for this CPU. | |
3469 | * - return freeable pages to the main free memory pool. | |
3470 | * | |
fc0abb14 | 3471 | * If we cannot acquire the cache chain mutex then just give up - we'll |
1da177e4 LT |
3472 | * try again on the next iteration. |
3473 | */ | |
3474 | static void cache_reap(void *unused) | |
3475 | { | |
3476 | struct list_head *walk; | |
e498be7d | 3477 | struct kmem_list3 *l3; |
1da177e4 | 3478 | |
fc0abb14 | 3479 | if (!mutex_trylock(&cache_chain_mutex)) { |
1da177e4 | 3480 | /* Give up. Setup the next iteration. */ |
b28a02de PE |
3481 | schedule_delayed_work(&__get_cpu_var(reap_work), |
3482 | REAPTIMEOUT_CPUC); | |
1da177e4 LT |
3483 | return; |
3484 | } | |
3485 | ||
3486 | list_for_each(walk, &cache_chain) { | |
343e0d7a | 3487 | struct kmem_cache *searchp; |
b28a02de | 3488 | struct list_head *p; |
1da177e4 LT |
3489 | int tofree; |
3490 | struct slab *slabp; | |
3491 | ||
343e0d7a | 3492 | searchp = list_entry(walk, struct kmem_cache, next); |
1da177e4 LT |
3493 | |
3494 | if (searchp->flags & SLAB_NO_REAP) | |
3495 | goto next; | |
3496 | ||
3497 | check_irq_on(); | |
3498 | ||
e498be7d CL |
3499 | l3 = searchp->nodelists[numa_node_id()]; |
3500 | if (l3->alien) | |
4484ebf1 | 3501 | drain_alien_cache(searchp, l3->alien); |
e498be7d | 3502 | spin_lock_irq(&l3->list_lock); |
1da177e4 | 3503 | |
9a2dba4b | 3504 | drain_array_locked(searchp, cpu_cache_get(searchp), 0, |
b28a02de | 3505 | numa_node_id()); |
1da177e4 | 3506 | |
e498be7d | 3507 | if (time_after(l3->next_reap, jiffies)) |
1da177e4 LT |
3508 | goto next_unlock; |
3509 | ||
e498be7d | 3510 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3; |
1da177e4 | 3511 | |
e498be7d CL |
3512 | if (l3->shared) |
3513 | drain_array_locked(searchp, l3->shared, 0, | |
b28a02de | 3514 | numa_node_id()); |
1da177e4 | 3515 | |
e498be7d CL |
3516 | if (l3->free_touched) { |
3517 | l3->free_touched = 0; | |
1da177e4 LT |
3518 | goto next_unlock; |
3519 | } | |
3520 | ||
b28a02de PE |
3521 | tofree = |
3522 | (l3->free_limit + 5 * searchp->num - | |
3523 | 1) / (5 * searchp->num); | |
1da177e4 | 3524 | do { |
e498be7d CL |
3525 | p = l3->slabs_free.next; |
3526 | if (p == &(l3->slabs_free)) | |
1da177e4 LT |
3527 | break; |
3528 | ||
3529 | slabp = list_entry(p, struct slab, list); | |
3530 | BUG_ON(slabp->inuse); | |
3531 | list_del(&slabp->list); | |
3532 | STATS_INC_REAPED(searchp); | |
3533 | ||
3534 | /* Safe to drop the lock. The slab is no longer | |
3535 | * linked to the cache. | |
3536 | * searchp cannot disappear, we hold | |
3537 | * cache_chain_lock | |
3538 | */ | |
e498be7d CL |
3539 | l3->free_objects -= searchp->num; |
3540 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 3541 | slab_destroy(searchp, slabp); |
e498be7d | 3542 | spin_lock_irq(&l3->list_lock); |
b28a02de PE |
3543 | } while (--tofree > 0); |
3544 | next_unlock: | |
e498be7d | 3545 | spin_unlock_irq(&l3->list_lock); |
b28a02de | 3546 | next: |
1da177e4 LT |
3547 | cond_resched(); |
3548 | } | |
3549 | check_irq_on(); | |
fc0abb14 | 3550 | mutex_unlock(&cache_chain_mutex); |
4ae7c039 | 3551 | drain_remote_pages(); |
1da177e4 | 3552 | /* Setup the next iteration */ |
cd61ef62 | 3553 | schedule_delayed_work(&__get_cpu_var(reap_work), REAPTIMEOUT_CPUC); |
1da177e4 LT |
3554 | } |
3555 | ||
3556 | #ifdef CONFIG_PROC_FS | |
3557 | ||
85289f98 | 3558 | static void print_slabinfo_header(struct seq_file *m) |
1da177e4 | 3559 | { |
85289f98 PE |
3560 | /* |
3561 | * Output format version, so at least we can change it | |
3562 | * without _too_ many complaints. | |
3563 | */ | |
1da177e4 | 3564 | #if STATS |
85289f98 | 3565 | seq_puts(m, "slabinfo - version: 2.1 (statistics)\n"); |
1da177e4 | 3566 | #else |
85289f98 | 3567 | seq_puts(m, "slabinfo - version: 2.1\n"); |
1da177e4 | 3568 | #endif |
85289f98 PE |
3569 | seq_puts(m, "# name <active_objs> <num_objs> <objsize> " |
3570 | "<objperslab> <pagesperslab>"); | |
3571 | seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); | |
3572 | seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); | |
1da177e4 | 3573 | #if STATS |
85289f98 PE |
3574 | seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> " |
3575 | "<error> <maxfreeable> <nodeallocs> <remotefrees>"); | |
3576 | seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>"); | |
1da177e4 | 3577 | #endif |
85289f98 PE |
3578 | seq_putc(m, '\n'); |
3579 | } | |
3580 | ||
3581 | static void *s_start(struct seq_file *m, loff_t *pos) | |
3582 | { | |
3583 | loff_t n = *pos; | |
3584 | struct list_head *p; | |
3585 | ||
fc0abb14 | 3586 | mutex_lock(&cache_chain_mutex); |
85289f98 PE |
3587 | if (!n) |
3588 | print_slabinfo_header(m); | |
1da177e4 LT |
3589 | p = cache_chain.next; |
3590 | while (n--) { | |
3591 | p = p->next; | |
3592 | if (p == &cache_chain) | |
3593 | return NULL; | |
3594 | } | |
343e0d7a | 3595 | return list_entry(p, struct kmem_cache, next); |
1da177e4 LT |
3596 | } |
3597 | ||
3598 | static void *s_next(struct seq_file *m, void *p, loff_t *pos) | |
3599 | { | |
343e0d7a | 3600 | struct kmem_cache *cachep = p; |
1da177e4 LT |
3601 | ++*pos; |
3602 | return cachep->next.next == &cache_chain ? NULL | |
343e0d7a | 3603 | : list_entry(cachep->next.next, struct kmem_cache, next); |
1da177e4 LT |
3604 | } |
3605 | ||
3606 | static void s_stop(struct seq_file *m, void *p) | |
3607 | { | |
fc0abb14 | 3608 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
3609 | } |
3610 | ||
3611 | static int s_show(struct seq_file *m, void *p) | |
3612 | { | |
343e0d7a | 3613 | struct kmem_cache *cachep = p; |
1da177e4 | 3614 | struct list_head *q; |
b28a02de PE |
3615 | struct slab *slabp; |
3616 | unsigned long active_objs; | |
3617 | unsigned long num_objs; | |
3618 | unsigned long active_slabs = 0; | |
3619 | unsigned long num_slabs, free_objects = 0, shared_avail = 0; | |
e498be7d | 3620 | const char *name; |
1da177e4 | 3621 | char *error = NULL; |
e498be7d CL |
3622 | int node; |
3623 | struct kmem_list3 *l3; | |
1da177e4 | 3624 | |
ca3b9b91 | 3625 | spin_lock(&cachep->spinlock); |
1da177e4 LT |
3626 | active_objs = 0; |
3627 | num_slabs = 0; | |
e498be7d CL |
3628 | for_each_online_node(node) { |
3629 | l3 = cachep->nodelists[node]; | |
3630 | if (!l3) | |
3631 | continue; | |
3632 | ||
ca3b9b91 RT |
3633 | check_irq_on(); |
3634 | spin_lock_irq(&l3->list_lock); | |
e498be7d | 3635 | |
b28a02de | 3636 | list_for_each(q, &l3->slabs_full) { |
e498be7d CL |
3637 | slabp = list_entry(q, struct slab, list); |
3638 | if (slabp->inuse != cachep->num && !error) | |
3639 | error = "slabs_full accounting error"; | |
3640 | active_objs += cachep->num; | |
3641 | active_slabs++; | |
3642 | } | |
b28a02de | 3643 | list_for_each(q, &l3->slabs_partial) { |
e498be7d CL |
3644 | slabp = list_entry(q, struct slab, list); |
3645 | if (slabp->inuse == cachep->num && !error) | |
3646 | error = "slabs_partial inuse accounting error"; | |
3647 | if (!slabp->inuse && !error) | |
3648 | error = "slabs_partial/inuse accounting error"; | |
3649 | active_objs += slabp->inuse; | |
3650 | active_slabs++; | |
3651 | } | |
b28a02de | 3652 | list_for_each(q, &l3->slabs_free) { |
e498be7d CL |
3653 | slabp = list_entry(q, struct slab, list); |
3654 | if (slabp->inuse && !error) | |
3655 | error = "slabs_free/inuse accounting error"; | |
3656 | num_slabs++; | |
3657 | } | |
3658 | free_objects += l3->free_objects; | |
4484ebf1 RT |
3659 | if (l3->shared) |
3660 | shared_avail += l3->shared->avail; | |
e498be7d | 3661 | |
ca3b9b91 | 3662 | spin_unlock_irq(&l3->list_lock); |
1da177e4 | 3663 | } |
b28a02de PE |
3664 | num_slabs += active_slabs; |
3665 | num_objs = num_slabs * cachep->num; | |
e498be7d | 3666 | if (num_objs - active_objs != free_objects && !error) |
1da177e4 LT |
3667 | error = "free_objects accounting error"; |
3668 | ||
b28a02de | 3669 | name = cachep->name; |
1da177e4 LT |
3670 | if (error) |
3671 | printk(KERN_ERR "slab: cache %s error: %s\n", name, error); | |
3672 | ||
3673 | seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", | |
3dafccf2 | 3674 | name, active_objs, num_objs, cachep->buffer_size, |
b28a02de | 3675 | cachep->num, (1 << cachep->gfporder)); |
1da177e4 | 3676 | seq_printf(m, " : tunables %4u %4u %4u", |
b28a02de | 3677 | cachep->limit, cachep->batchcount, cachep->shared); |
e498be7d | 3678 | seq_printf(m, " : slabdata %6lu %6lu %6lu", |
b28a02de | 3679 | active_slabs, num_slabs, shared_avail); |
1da177e4 | 3680 | #if STATS |
b28a02de | 3681 | { /* list3 stats */ |
1da177e4 LT |
3682 | unsigned long high = cachep->high_mark; |
3683 | unsigned long allocs = cachep->num_allocations; | |
3684 | unsigned long grown = cachep->grown; | |
3685 | unsigned long reaped = cachep->reaped; | |
3686 | unsigned long errors = cachep->errors; | |
3687 | unsigned long max_freeable = cachep->max_freeable; | |
1da177e4 | 3688 | unsigned long node_allocs = cachep->node_allocs; |
e498be7d | 3689 | unsigned long node_frees = cachep->node_frees; |
1da177e4 | 3690 | |
e498be7d | 3691 | seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu \ |
b28a02de | 3692 | %4lu %4lu %4lu %4lu", allocs, high, grown, reaped, errors, max_freeable, node_allocs, node_frees); |
1da177e4 LT |
3693 | } |
3694 | /* cpu stats */ | |
3695 | { | |
3696 | unsigned long allochit = atomic_read(&cachep->allochit); | |
3697 | unsigned long allocmiss = atomic_read(&cachep->allocmiss); | |
3698 | unsigned long freehit = atomic_read(&cachep->freehit); | |
3699 | unsigned long freemiss = atomic_read(&cachep->freemiss); | |
3700 | ||
3701 | seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", | |
b28a02de | 3702 | allochit, allocmiss, freehit, freemiss); |
1da177e4 LT |
3703 | } |
3704 | #endif | |
3705 | seq_putc(m, '\n'); | |
ca3b9b91 | 3706 | spin_unlock(&cachep->spinlock); |
1da177e4 LT |
3707 | return 0; |
3708 | } | |
3709 | ||
3710 | /* | |
3711 | * slabinfo_op - iterator that generates /proc/slabinfo | |
3712 | * | |
3713 | * Output layout: | |
3714 | * cache-name | |
3715 | * num-active-objs | |
3716 | * total-objs | |
3717 | * object size | |
3718 | * num-active-slabs | |
3719 | * total-slabs | |
3720 | * num-pages-per-slab | |
3721 | * + further values on SMP and with statistics enabled | |
3722 | */ | |
3723 | ||
3724 | struct seq_operations slabinfo_op = { | |
b28a02de PE |
3725 | .start = s_start, |
3726 | .next = s_next, | |
3727 | .stop = s_stop, | |
3728 | .show = s_show, | |
1da177e4 LT |
3729 | }; |
3730 | ||
3731 | #define MAX_SLABINFO_WRITE 128 | |
3732 | /** | |
3733 | * slabinfo_write - Tuning for the slab allocator | |
3734 | * @file: unused | |
3735 | * @buffer: user buffer | |
3736 | * @count: data length | |
3737 | * @ppos: unused | |
3738 | */ | |
b28a02de PE |
3739 | ssize_t slabinfo_write(struct file *file, const char __user * buffer, |
3740 | size_t count, loff_t *ppos) | |
1da177e4 | 3741 | { |
b28a02de | 3742 | char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; |
1da177e4 LT |
3743 | int limit, batchcount, shared, res; |
3744 | struct list_head *p; | |
b28a02de | 3745 | |
1da177e4 LT |
3746 | if (count > MAX_SLABINFO_WRITE) |
3747 | return -EINVAL; | |
3748 | if (copy_from_user(&kbuf, buffer, count)) | |
3749 | return -EFAULT; | |
b28a02de | 3750 | kbuf[MAX_SLABINFO_WRITE] = '\0'; |
1da177e4 LT |
3751 | |
3752 | tmp = strchr(kbuf, ' '); | |
3753 | if (!tmp) | |
3754 | return -EINVAL; | |
3755 | *tmp = '\0'; | |
3756 | tmp++; | |
3757 | if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) | |
3758 | return -EINVAL; | |
3759 | ||
3760 | /* Find the cache in the chain of caches. */ | |
fc0abb14 | 3761 | mutex_lock(&cache_chain_mutex); |
1da177e4 | 3762 | res = -EINVAL; |
b28a02de | 3763 | list_for_each(p, &cache_chain) { |
343e0d7a PE |
3764 | struct kmem_cache *cachep = list_entry(p, struct kmem_cache, |
3765 | next); | |
1da177e4 LT |
3766 | |
3767 | if (!strcmp(cachep->name, kbuf)) { | |
3768 | if (limit < 1 || | |
3769 | batchcount < 1 || | |
b28a02de | 3770 | batchcount > limit || shared < 0) { |
e498be7d | 3771 | res = 0; |
1da177e4 | 3772 | } else { |
e498be7d | 3773 | res = do_tune_cpucache(cachep, limit, |
b28a02de | 3774 | batchcount, shared); |
1da177e4 LT |
3775 | } |
3776 | break; | |
3777 | } | |
3778 | } | |
fc0abb14 | 3779 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
3780 | if (res >= 0) |
3781 | res = count; | |
3782 | return res; | |
3783 | } | |
3784 | #endif | |
3785 | ||
00e145b6 MS |
3786 | /** |
3787 | * ksize - get the actual amount of memory allocated for a given object | |
3788 | * @objp: Pointer to the object | |
3789 | * | |
3790 | * kmalloc may internally round up allocations and return more memory | |
3791 | * than requested. ksize() can be used to determine the actual amount of | |
3792 | * memory allocated. The caller may use this additional memory, even though | |
3793 | * a smaller amount of memory was initially specified with the kmalloc call. | |
3794 | * The caller must guarantee that objp points to a valid object previously | |
3795 | * allocated with either kmalloc() or kmem_cache_alloc(). The object | |
3796 | * must not be freed during the duration of the call. | |
3797 | */ | |
1da177e4 LT |
3798 | unsigned int ksize(const void *objp) |
3799 | { | |
00e145b6 MS |
3800 | if (unlikely(objp == NULL)) |
3801 | return 0; | |
1da177e4 | 3802 | |
6ed5eb22 | 3803 | return obj_size(virt_to_cache(objp)); |
1da177e4 | 3804 | } |