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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. | |
58 | * Several members in kmem_cache_t and struct slab never change, they | |
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 PE |
246 | struct rcu_head head; |
247 | kmem_cache_t *cachep; | |
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; | |
297 | spinlock_t list_lock; | |
298 | struct array_cache *shared; /* shared per node */ | |
299 | struct array_cache **alien; /* on other nodes */ | |
1da177e4 LT |
300 | }; |
301 | ||
e498be7d CL |
302 | /* |
303 | * Need this for bootstrapping a per node allocator. | |
304 | */ | |
305 | #define NUM_INIT_LISTS (2 * MAX_NUMNODES + 1) | |
306 | struct kmem_list3 __initdata initkmem_list3[NUM_INIT_LISTS]; | |
307 | #define CACHE_CACHE 0 | |
308 | #define SIZE_AC 1 | |
309 | #define SIZE_L3 (1 + MAX_NUMNODES) | |
310 | ||
311 | /* | |
7243cc05 | 312 | * This function must be completely optimized away if |
e498be7d CL |
313 | * a constant is passed to it. Mostly the same as |
314 | * what is in linux/slab.h except it returns an | |
315 | * index. | |
316 | */ | |
7243cc05 | 317 | static __always_inline int index_of(const size_t size) |
e498be7d CL |
318 | { |
319 | if (__builtin_constant_p(size)) { | |
320 | int i = 0; | |
321 | ||
322 | #define CACHE(x) \ | |
323 | if (size <=x) \ | |
324 | return i; \ | |
325 | else \ | |
326 | i++; | |
327 | #include "linux/kmalloc_sizes.h" | |
328 | #undef CACHE | |
329 | { | |
330 | extern void __bad_size(void); | |
331 | __bad_size(); | |
332 | } | |
7243cc05 IK |
333 | } else |
334 | BUG(); | |
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 | |
e498be7d CL |
341 | static inline void kmem_list3_init(struct kmem_list3 *parent) |
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; | |
348 | spin_lock_init(&parent->list_lock); | |
349 | parent->free_objects = 0; | |
350 | parent->free_touched = 0; | |
351 | } | |
352 | ||
353 | #define MAKE_LIST(cachep, listp, slab, nodeid) \ | |
354 | do { \ | |
355 | INIT_LIST_HEAD(listp); \ | |
356 | list_splice(&(cachep->nodelists[nodeid]->slab), listp); \ | |
357 | } while (0) | |
358 | ||
359 | #define MAKE_ALL_LISTS(cachep, ptr, nodeid) \ | |
360 | do { \ | |
361 | MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \ | |
362 | MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \ | |
363 | MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \ | |
364 | } while (0) | |
1da177e4 LT |
365 | |
366 | /* | |
367 | * kmem_cache_t | |
368 | * | |
369 | * manages a cache. | |
370 | */ | |
b28a02de | 371 | |
2109a2d1 | 372 | struct kmem_cache { |
1da177e4 | 373 | /* 1) per-cpu data, touched during every alloc/free */ |
b28a02de PE |
374 | struct array_cache *array[NR_CPUS]; |
375 | unsigned int batchcount; | |
376 | unsigned int limit; | |
377 | unsigned int shared; | |
378 | unsigned int objsize; | |
e498be7d | 379 | /* 2) touched by every alloc & free from the backend */ |
b28a02de PE |
380 | struct kmem_list3 *nodelists[MAX_NUMNODES]; |
381 | unsigned int flags; /* constant flags */ | |
382 | unsigned int num; /* # of objs per slab */ | |
383 | spinlock_t spinlock; | |
1da177e4 LT |
384 | |
385 | /* 3) cache_grow/shrink */ | |
386 | /* order of pgs per slab (2^n) */ | |
b28a02de | 387 | unsigned int gfporder; |
1da177e4 LT |
388 | |
389 | /* force GFP flags, e.g. GFP_DMA */ | |
b28a02de | 390 | gfp_t gfpflags; |
1da177e4 | 391 | |
b28a02de PE |
392 | size_t colour; /* cache colouring range */ |
393 | unsigned int colour_off; /* colour offset */ | |
394 | unsigned int colour_next; /* cache colouring */ | |
395 | kmem_cache_t *slabp_cache; | |
396 | unsigned int slab_size; | |
397 | unsigned int dflags; /* dynamic flags */ | |
1da177e4 LT |
398 | |
399 | /* constructor func */ | |
b28a02de | 400 | void (*ctor) (void *, kmem_cache_t *, unsigned long); |
1da177e4 LT |
401 | |
402 | /* de-constructor func */ | |
b28a02de | 403 | void (*dtor) (void *, kmem_cache_t *, 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 | |
b28a02de PE |
426 | int dbghead; |
427 | int reallen; | |
1da177e4 LT |
428 | #endif |
429 | }; | |
430 | ||
431 | #define CFLGS_OFF_SLAB (0x80000000UL) | |
432 | #define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB) | |
433 | ||
434 | #define BATCHREFILL_LIMIT 16 | |
435 | /* Optimization question: fewer reaps means less | |
436 | * probability for unnessary cpucache drain/refill cycles. | |
437 | * | |
dc6f3f27 | 438 | * OTOH the cpuarrays can contain lots of objects, |
1da177e4 LT |
439 | * which could lock up otherwise freeable slabs. |
440 | */ | |
441 | #define REAPTIMEOUT_CPUC (2*HZ) | |
442 | #define REAPTIMEOUT_LIST3 (4*HZ) | |
443 | ||
444 | #if STATS | |
445 | #define STATS_INC_ACTIVE(x) ((x)->num_active++) | |
446 | #define STATS_DEC_ACTIVE(x) ((x)->num_active--) | |
447 | #define STATS_INC_ALLOCED(x) ((x)->num_allocations++) | |
448 | #define STATS_INC_GROWN(x) ((x)->grown++) | |
449 | #define STATS_INC_REAPED(x) ((x)->reaped++) | |
450 | #define STATS_SET_HIGH(x) do { if ((x)->num_active > (x)->high_mark) \ | |
451 | (x)->high_mark = (x)->num_active; \ | |
452 | } while (0) | |
453 | #define STATS_INC_ERR(x) ((x)->errors++) | |
454 | #define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++) | |
e498be7d | 455 | #define STATS_INC_NODEFREES(x) ((x)->node_frees++) |
1da177e4 LT |
456 | #define STATS_SET_FREEABLE(x, i) \ |
457 | do { if ((x)->max_freeable < i) \ | |
458 | (x)->max_freeable = i; \ | |
459 | } while (0) | |
460 | ||
461 | #define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit) | |
462 | #define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss) | |
463 | #define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit) | |
464 | #define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss) | |
465 | #else | |
466 | #define STATS_INC_ACTIVE(x) do { } while (0) | |
467 | #define STATS_DEC_ACTIVE(x) do { } while (0) | |
468 | #define STATS_INC_ALLOCED(x) do { } while (0) | |
469 | #define STATS_INC_GROWN(x) do { } while (0) | |
470 | #define STATS_INC_REAPED(x) do { } while (0) | |
471 | #define STATS_SET_HIGH(x) do { } while (0) | |
472 | #define STATS_INC_ERR(x) do { } while (0) | |
473 | #define STATS_INC_NODEALLOCS(x) do { } while (0) | |
e498be7d | 474 | #define STATS_INC_NODEFREES(x) do { } while (0) |
1da177e4 LT |
475 | #define STATS_SET_FREEABLE(x, i) \ |
476 | do { } while (0) | |
477 | ||
478 | #define STATS_INC_ALLOCHIT(x) do { } while (0) | |
479 | #define STATS_INC_ALLOCMISS(x) do { } while (0) | |
480 | #define STATS_INC_FREEHIT(x) do { } while (0) | |
481 | #define STATS_INC_FREEMISS(x) do { } while (0) | |
482 | #endif | |
483 | ||
484 | #if DEBUG | |
485 | /* Magic nums for obj red zoning. | |
486 | * Placed in the first word before and the first word after an obj. | |
487 | */ | |
488 | #define RED_INACTIVE 0x5A2CF071UL /* when obj is inactive */ | |
489 | #define RED_ACTIVE 0x170FC2A5UL /* when obj is active */ | |
490 | ||
491 | /* ...and for poisoning */ | |
492 | #define POISON_INUSE 0x5a /* for use-uninitialised poisoning */ | |
493 | #define POISON_FREE 0x6b /* for use-after-free poisoning */ | |
494 | #define POISON_END 0xa5 /* end-byte of poisoning */ | |
495 | ||
496 | /* memory layout of objects: | |
497 | * 0 : objp | |
498 | * 0 .. cachep->dbghead - BYTES_PER_WORD - 1: padding. This ensures that | |
499 | * the end of an object is aligned with the end of the real | |
500 | * allocation. Catches writes behind the end of the allocation. | |
501 | * cachep->dbghead - BYTES_PER_WORD .. cachep->dbghead - 1: | |
502 | * redzone word. | |
503 | * cachep->dbghead: The real object. | |
504 | * cachep->objsize - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long] | |
505 | * cachep->objsize - 1* BYTES_PER_WORD: last caller address [BYTES_PER_WORD long] | |
506 | */ | |
507 | static int obj_dbghead(kmem_cache_t *cachep) | |
508 | { | |
509 | return cachep->dbghead; | |
510 | } | |
511 | ||
512 | static int obj_reallen(kmem_cache_t *cachep) | |
513 | { | |
514 | return cachep->reallen; | |
515 | } | |
516 | ||
517 | static unsigned long *dbg_redzone1(kmem_cache_t *cachep, void *objp) | |
518 | { | |
519 | BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); | |
520 | return (unsigned long*) (objp+obj_dbghead(cachep)-BYTES_PER_WORD); | |
521 | } | |
522 | ||
523 | static unsigned long *dbg_redzone2(kmem_cache_t *cachep, void *objp) | |
524 | { | |
525 | BUG_ON(!(cachep->flags & SLAB_RED_ZONE)); | |
526 | if (cachep->flags & SLAB_STORE_USER) | |
b28a02de PE |
527 | return (unsigned long *)(objp + cachep->objsize - |
528 | 2 * BYTES_PER_WORD); | |
529 | return (unsigned long *)(objp + cachep->objsize - BYTES_PER_WORD); | |
1da177e4 LT |
530 | } |
531 | ||
532 | static void **dbg_userword(kmem_cache_t *cachep, void *objp) | |
533 | { | |
534 | BUG_ON(!(cachep->flags & SLAB_STORE_USER)); | |
b28a02de | 535 | return (void **)(objp + cachep->objsize - BYTES_PER_WORD); |
1da177e4 LT |
536 | } |
537 | ||
538 | #else | |
539 | ||
540 | #define obj_dbghead(x) 0 | |
541 | #define obj_reallen(cachep) (cachep->objsize) | |
542 | #define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long *)NULL;}) | |
543 | #define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long *)NULL;}) | |
544 | #define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;}) | |
545 | ||
546 | #endif | |
547 | ||
548 | /* | |
549 | * Maximum size of an obj (in 2^order pages) | |
550 | * and absolute limit for the gfp order. | |
551 | */ | |
552 | #if defined(CONFIG_LARGE_ALLOCS) | |
553 | #define MAX_OBJ_ORDER 13 /* up to 32Mb */ | |
554 | #define MAX_GFP_ORDER 13 /* up to 32Mb */ | |
555 | #elif defined(CONFIG_MMU) | |
556 | #define MAX_OBJ_ORDER 5 /* 32 pages */ | |
557 | #define MAX_GFP_ORDER 5 /* 32 pages */ | |
558 | #else | |
559 | #define MAX_OBJ_ORDER 8 /* up to 1Mb */ | |
560 | #define MAX_GFP_ORDER 8 /* up to 1Mb */ | |
561 | #endif | |
562 | ||
563 | /* | |
564 | * Do not go above this order unless 0 objects fit into the slab. | |
565 | */ | |
566 | #define BREAK_GFP_ORDER_HI 1 | |
567 | #define BREAK_GFP_ORDER_LO 0 | |
568 | static int slab_break_gfp_order = BREAK_GFP_ORDER_LO; | |
569 | ||
065d41cb | 570 | /* Functions for storing/retrieving the cachep and or slab from the |
1da177e4 LT |
571 | * global 'mem_map'. These are used to find the slab an obj belongs to. |
572 | * With kfree(), these are used to find the cache which an obj belongs to. | |
573 | */ | |
065d41cb PE |
574 | static inline void page_set_cache(struct page *page, struct kmem_cache *cache) |
575 | { | |
576 | page->lru.next = (struct list_head *)cache; | |
577 | } | |
578 | ||
579 | static inline struct kmem_cache *page_get_cache(struct page *page) | |
580 | { | |
581 | return (struct kmem_cache *)page->lru.next; | |
582 | } | |
583 | ||
584 | static inline void page_set_slab(struct page *page, struct slab *slab) | |
585 | { | |
586 | page->lru.prev = (struct list_head *)slab; | |
587 | } | |
588 | ||
589 | static inline struct slab *page_get_slab(struct page *page) | |
590 | { | |
591 | return (struct slab *)page->lru.prev; | |
592 | } | |
1da177e4 LT |
593 | |
594 | /* These are the default caches for kmalloc. Custom caches can have other sizes. */ | |
595 | struct cache_sizes malloc_sizes[] = { | |
596 | #define CACHE(x) { .cs_size = (x) }, | |
597 | #include <linux/kmalloc_sizes.h> | |
598 | CACHE(ULONG_MAX) | |
599 | #undef CACHE | |
600 | }; | |
601 | EXPORT_SYMBOL(malloc_sizes); | |
602 | ||
603 | /* Must match cache_sizes above. Out of line to keep cache footprint low. */ | |
604 | struct cache_names { | |
605 | char *name; | |
606 | char *name_dma; | |
607 | }; | |
608 | ||
609 | static struct cache_names __initdata cache_names[] = { | |
610 | #define CACHE(x) { .name = "size-" #x, .name_dma = "size-" #x "(DMA)" }, | |
611 | #include <linux/kmalloc_sizes.h> | |
b28a02de | 612 | {NULL,} |
1da177e4 LT |
613 | #undef CACHE |
614 | }; | |
615 | ||
616 | static struct arraycache_init initarray_cache __initdata = | |
b28a02de | 617 | { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; |
1da177e4 | 618 | static struct arraycache_init initarray_generic = |
b28a02de | 619 | { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} }; |
1da177e4 LT |
620 | |
621 | /* internal cache of cache description objs */ | |
622 | static kmem_cache_t cache_cache = { | |
b28a02de PE |
623 | .batchcount = 1, |
624 | .limit = BOOT_CPUCACHE_ENTRIES, | |
625 | .shared = 1, | |
626 | .objsize = sizeof(kmem_cache_t), | |
627 | .flags = SLAB_NO_REAP, | |
628 | .spinlock = SPIN_LOCK_UNLOCKED, | |
629 | .name = "kmem_cache", | |
1da177e4 | 630 | #if DEBUG |
b28a02de | 631 | .reallen = sizeof(kmem_cache_t), |
1da177e4 LT |
632 | #endif |
633 | }; | |
634 | ||
635 | /* Guard access to the cache-chain. */ | |
fc0abb14 | 636 | static DEFINE_MUTEX(cache_chain_mutex); |
1da177e4 LT |
637 | static struct list_head cache_chain; |
638 | ||
639 | /* | |
640 | * vm_enough_memory() looks at this to determine how many | |
641 | * slab-allocated pages are possibly freeable under pressure | |
642 | * | |
643 | * SLAB_RECLAIM_ACCOUNT turns this on per-slab | |
644 | */ | |
645 | atomic_t slab_reclaim_pages; | |
1da177e4 LT |
646 | |
647 | /* | |
648 | * chicken and egg problem: delay the per-cpu array allocation | |
649 | * until the general caches are up. | |
650 | */ | |
651 | static enum { | |
652 | NONE, | |
e498be7d CL |
653 | PARTIAL_AC, |
654 | PARTIAL_L3, | |
1da177e4 LT |
655 | FULL |
656 | } g_cpucache_up; | |
657 | ||
658 | static DEFINE_PER_CPU(struct work_struct, reap_work); | |
659 | ||
b28a02de PE |
660 | static void free_block(kmem_cache_t *cachep, void **objpp, int len, int node); |
661 | static void enable_cpucache(kmem_cache_t *cachep); | |
662 | static void cache_reap(void *unused); | |
e498be7d | 663 | static int __node_shrink(kmem_cache_t *cachep, int node); |
1da177e4 LT |
664 | |
665 | static inline struct array_cache *ac_data(kmem_cache_t *cachep) | |
666 | { | |
667 | return cachep->array[smp_processor_id()]; | |
668 | } | |
669 | ||
dd0fc66f | 670 | static inline kmem_cache_t *__find_general_cachep(size_t size, gfp_t gfpflags) |
1da177e4 LT |
671 | { |
672 | struct cache_sizes *csizep = malloc_sizes; | |
673 | ||
674 | #if DEBUG | |
675 | /* This happens if someone tries to call | |
b28a02de PE |
676 | * kmem_cache_create(), or __kmalloc(), before |
677 | * the generic caches are initialized. | |
678 | */ | |
c7e43c78 | 679 | BUG_ON(malloc_sizes[INDEX_AC].cs_cachep == NULL); |
1da177e4 LT |
680 | #endif |
681 | while (size > csizep->cs_size) | |
682 | csizep++; | |
683 | ||
684 | /* | |
0abf40c1 | 685 | * Really subtle: The last entry with cs->cs_size==ULONG_MAX |
1da177e4 LT |
686 | * has cs_{dma,}cachep==NULL. Thus no special case |
687 | * for large kmalloc calls required. | |
688 | */ | |
689 | if (unlikely(gfpflags & GFP_DMA)) | |
690 | return csizep->cs_dmacachep; | |
691 | return csizep->cs_cachep; | |
692 | } | |
693 | ||
dd0fc66f | 694 | kmem_cache_t *kmem_find_general_cachep(size_t size, gfp_t gfpflags) |
97e2bde4 MS |
695 | { |
696 | return __find_general_cachep(size, gfpflags); | |
697 | } | |
698 | EXPORT_SYMBOL(kmem_find_general_cachep); | |
699 | ||
1da177e4 LT |
700 | /* Cal the num objs, wastage, and bytes left over for a given slab size. */ |
701 | static void cache_estimate(unsigned long gfporder, size_t size, size_t align, | |
b28a02de | 702 | int flags, size_t *left_over, unsigned int *num) |
1da177e4 LT |
703 | { |
704 | int i; | |
b28a02de | 705 | size_t wastage = PAGE_SIZE << gfporder; |
1da177e4 LT |
706 | size_t extra = 0; |
707 | size_t base = 0; | |
708 | ||
709 | if (!(flags & CFLGS_OFF_SLAB)) { | |
710 | base = sizeof(struct slab); | |
711 | extra = sizeof(kmem_bufctl_t); | |
712 | } | |
713 | i = 0; | |
b28a02de | 714 | while (i * size + ALIGN(base + i * extra, align) <= wastage) |
1da177e4 LT |
715 | i++; |
716 | if (i > 0) | |
717 | i--; | |
718 | ||
719 | if (i > SLAB_LIMIT) | |
720 | i = SLAB_LIMIT; | |
721 | ||
722 | *num = i; | |
b28a02de PE |
723 | wastage -= i * size; |
724 | wastage -= ALIGN(base + i * extra, align); | |
1da177e4 LT |
725 | *left_over = wastage; |
726 | } | |
727 | ||
728 | #define slab_error(cachep, msg) __slab_error(__FUNCTION__, cachep, msg) | |
729 | ||
730 | static void __slab_error(const char *function, kmem_cache_t *cachep, char *msg) | |
731 | { | |
732 | printk(KERN_ERR "slab error in %s(): cache `%s': %s\n", | |
b28a02de | 733 | function, cachep->name, msg); |
1da177e4 LT |
734 | dump_stack(); |
735 | } | |
736 | ||
737 | /* | |
738 | * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz | |
739 | * via the workqueue/eventd. | |
740 | * Add the CPU number into the expiration time to minimize the possibility of | |
741 | * the CPUs getting into lockstep and contending for the global cache chain | |
742 | * lock. | |
743 | */ | |
744 | static void __devinit start_cpu_timer(int cpu) | |
745 | { | |
746 | struct work_struct *reap_work = &per_cpu(reap_work, cpu); | |
747 | ||
748 | /* | |
749 | * When this gets called from do_initcalls via cpucache_init(), | |
750 | * init_workqueues() has already run, so keventd will be setup | |
751 | * at that time. | |
752 | */ | |
753 | if (keventd_up() && reap_work->func == NULL) { | |
754 | INIT_WORK(reap_work, cache_reap, NULL); | |
755 | schedule_delayed_work_on(cpu, reap_work, HZ + 3 * cpu); | |
756 | } | |
757 | } | |
758 | ||
e498be7d | 759 | static struct array_cache *alloc_arraycache(int node, int entries, |
b28a02de | 760 | int batchcount) |
1da177e4 | 761 | { |
b28a02de | 762 | int memsize = sizeof(void *) * entries + sizeof(struct array_cache); |
1da177e4 LT |
763 | struct array_cache *nc = NULL; |
764 | ||
e498be7d | 765 | nc = kmalloc_node(memsize, GFP_KERNEL, node); |
1da177e4 LT |
766 | if (nc) { |
767 | nc->avail = 0; | |
768 | nc->limit = entries; | |
769 | nc->batchcount = batchcount; | |
770 | nc->touched = 0; | |
e498be7d | 771 | spin_lock_init(&nc->lock); |
1da177e4 LT |
772 | } |
773 | return nc; | |
774 | } | |
775 | ||
e498be7d | 776 | #ifdef CONFIG_NUMA |
dc85da15 CL |
777 | static void *__cache_alloc_node(kmem_cache_t *, gfp_t, int); |
778 | ||
e498be7d CL |
779 | static inline struct array_cache **alloc_alien_cache(int node, int limit) |
780 | { | |
781 | struct array_cache **ac_ptr; | |
b28a02de | 782 | int memsize = sizeof(void *) * MAX_NUMNODES; |
e498be7d CL |
783 | int i; |
784 | ||
785 | if (limit > 1) | |
786 | limit = 12; | |
787 | ac_ptr = kmalloc_node(memsize, GFP_KERNEL, node); | |
788 | if (ac_ptr) { | |
789 | for_each_node(i) { | |
790 | if (i == node || !node_online(i)) { | |
791 | ac_ptr[i] = NULL; | |
792 | continue; | |
793 | } | |
794 | ac_ptr[i] = alloc_arraycache(node, limit, 0xbaadf00d); | |
795 | if (!ac_ptr[i]) { | |
b28a02de | 796 | for (i--; i <= 0; i--) |
e498be7d CL |
797 | kfree(ac_ptr[i]); |
798 | kfree(ac_ptr); | |
799 | return NULL; | |
800 | } | |
801 | } | |
802 | } | |
803 | return ac_ptr; | |
804 | } | |
805 | ||
806 | static inline void free_alien_cache(struct array_cache **ac_ptr) | |
807 | { | |
808 | int i; | |
809 | ||
810 | if (!ac_ptr) | |
811 | return; | |
812 | ||
813 | for_each_node(i) | |
b28a02de | 814 | kfree(ac_ptr[i]); |
e498be7d CL |
815 | |
816 | kfree(ac_ptr); | |
817 | } | |
818 | ||
b28a02de PE |
819 | static inline void __drain_alien_cache(kmem_cache_t *cachep, |
820 | struct array_cache *ac, int node) | |
e498be7d CL |
821 | { |
822 | struct kmem_list3 *rl3 = cachep->nodelists[node]; | |
823 | ||
824 | if (ac->avail) { | |
825 | spin_lock(&rl3->list_lock); | |
ff69416e | 826 | free_block(cachep, ac->entry, ac->avail, node); |
e498be7d CL |
827 | ac->avail = 0; |
828 | spin_unlock(&rl3->list_lock); | |
829 | } | |
830 | } | |
831 | ||
832 | static void drain_alien_cache(kmem_cache_t *cachep, struct kmem_list3 *l3) | |
833 | { | |
b28a02de | 834 | int i = 0; |
e498be7d CL |
835 | struct array_cache *ac; |
836 | unsigned long flags; | |
837 | ||
838 | for_each_online_node(i) { | |
839 | ac = l3->alien[i]; | |
840 | if (ac) { | |
841 | spin_lock_irqsave(&ac->lock, flags); | |
842 | __drain_alien_cache(cachep, ac, i); | |
843 | spin_unlock_irqrestore(&ac->lock, flags); | |
844 | } | |
845 | } | |
846 | } | |
847 | #else | |
848 | #define alloc_alien_cache(node, limit) do { } while (0) | |
849 | #define free_alien_cache(ac_ptr) do { } while (0) | |
850 | #define drain_alien_cache(cachep, l3) do { } while (0) | |
851 | #endif | |
852 | ||
1da177e4 | 853 | static int __devinit cpuup_callback(struct notifier_block *nfb, |
b28a02de | 854 | unsigned long action, void *hcpu) |
1da177e4 LT |
855 | { |
856 | long cpu = (long)hcpu; | |
b28a02de | 857 | kmem_cache_t *cachep; |
e498be7d CL |
858 | struct kmem_list3 *l3 = NULL; |
859 | int node = cpu_to_node(cpu); | |
860 | int memsize = sizeof(struct kmem_list3); | |
1da177e4 LT |
861 | |
862 | switch (action) { | |
863 | case CPU_UP_PREPARE: | |
fc0abb14 | 864 | mutex_lock(&cache_chain_mutex); |
e498be7d CL |
865 | /* we need to do this right in the beginning since |
866 | * alloc_arraycache's are going to use this list. | |
867 | * kmalloc_node allows us to add the slab to the right | |
868 | * kmem_list3 and not this cpu's kmem_list3 | |
869 | */ | |
870 | ||
1da177e4 | 871 | list_for_each_entry(cachep, &cache_chain, next) { |
e498be7d CL |
872 | /* setup the size64 kmemlist for cpu before we can |
873 | * begin anything. Make sure some other cpu on this | |
874 | * node has not already allocated this | |
875 | */ | |
876 | if (!cachep->nodelists[node]) { | |
877 | if (!(l3 = kmalloc_node(memsize, | |
b28a02de | 878 | GFP_KERNEL, node))) |
e498be7d CL |
879 | goto bad; |
880 | kmem_list3_init(l3); | |
881 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + | |
b28a02de | 882 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
e498be7d CL |
883 | |
884 | cachep->nodelists[node] = l3; | |
885 | } | |
1da177e4 | 886 | |
e498be7d CL |
887 | spin_lock_irq(&cachep->nodelists[node]->list_lock); |
888 | cachep->nodelists[node]->free_limit = | |
b28a02de PE |
889 | (1 + nr_cpus_node(node)) * |
890 | cachep->batchcount + cachep->num; | |
e498be7d CL |
891 | spin_unlock_irq(&cachep->nodelists[node]->list_lock); |
892 | } | |
893 | ||
894 | /* Now we can go ahead with allocating the shared array's | |
b28a02de | 895 | & array cache's */ |
e498be7d | 896 | list_for_each_entry(cachep, &cache_chain, next) { |
cd105df4 TK |
897 | struct array_cache *nc; |
898 | ||
e498be7d | 899 | nc = alloc_arraycache(node, cachep->limit, |
b28a02de | 900 | cachep->batchcount); |
1da177e4 LT |
901 | if (!nc) |
902 | goto bad; | |
1da177e4 | 903 | cachep->array[cpu] = nc; |
1da177e4 | 904 | |
e498be7d CL |
905 | l3 = cachep->nodelists[node]; |
906 | BUG_ON(!l3); | |
907 | if (!l3->shared) { | |
908 | if (!(nc = alloc_arraycache(node, | |
b28a02de PE |
909 | cachep->shared * |
910 | cachep->batchcount, | |
911 | 0xbaadf00d))) | |
912 | goto bad; | |
e498be7d CL |
913 | |
914 | /* we are serialised from CPU_DEAD or | |
b28a02de | 915 | CPU_UP_CANCELLED by the cpucontrol lock */ |
e498be7d CL |
916 | l3->shared = nc; |
917 | } | |
1da177e4 | 918 | } |
fc0abb14 | 919 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
920 | break; |
921 | case CPU_ONLINE: | |
922 | start_cpu_timer(cpu); | |
923 | break; | |
924 | #ifdef CONFIG_HOTPLUG_CPU | |
925 | case CPU_DEAD: | |
926 | /* fall thru */ | |
927 | case CPU_UP_CANCELED: | |
fc0abb14 | 928 | mutex_lock(&cache_chain_mutex); |
1da177e4 LT |
929 | |
930 | list_for_each_entry(cachep, &cache_chain, next) { | |
931 | struct array_cache *nc; | |
e498be7d | 932 | cpumask_t mask; |
1da177e4 | 933 | |
e498be7d | 934 | mask = node_to_cpumask(node); |
1da177e4 LT |
935 | spin_lock_irq(&cachep->spinlock); |
936 | /* cpu is dead; no one can alloc from it. */ | |
937 | nc = cachep->array[cpu]; | |
938 | cachep->array[cpu] = NULL; | |
e498be7d CL |
939 | l3 = cachep->nodelists[node]; |
940 | ||
941 | if (!l3) | |
942 | goto unlock_cache; | |
943 | ||
944 | spin_lock(&l3->list_lock); | |
945 | ||
946 | /* Free limit for this kmem_list3 */ | |
947 | l3->free_limit -= cachep->batchcount; | |
948 | if (nc) | |
ff69416e | 949 | free_block(cachep, nc->entry, nc->avail, node); |
e498be7d CL |
950 | |
951 | if (!cpus_empty(mask)) { | |
b28a02de PE |
952 | spin_unlock(&l3->list_lock); |
953 | goto unlock_cache; | |
954 | } | |
e498be7d CL |
955 | |
956 | if (l3->shared) { | |
957 | free_block(cachep, l3->shared->entry, | |
b28a02de | 958 | l3->shared->avail, node); |
e498be7d CL |
959 | kfree(l3->shared); |
960 | l3->shared = NULL; | |
961 | } | |
962 | if (l3->alien) { | |
963 | drain_alien_cache(cachep, l3); | |
964 | free_alien_cache(l3->alien); | |
965 | l3->alien = NULL; | |
966 | } | |
967 | ||
968 | /* free slabs belonging to this node */ | |
969 | if (__node_shrink(cachep, node)) { | |
970 | cachep->nodelists[node] = NULL; | |
971 | spin_unlock(&l3->list_lock); | |
972 | kfree(l3); | |
973 | } else { | |
974 | spin_unlock(&l3->list_lock); | |
975 | } | |
b28a02de | 976 | unlock_cache: |
1da177e4 LT |
977 | spin_unlock_irq(&cachep->spinlock); |
978 | kfree(nc); | |
979 | } | |
fc0abb14 | 980 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
981 | break; |
982 | #endif | |
983 | } | |
984 | return NOTIFY_OK; | |
b28a02de | 985 | bad: |
fc0abb14 | 986 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
987 | return NOTIFY_BAD; |
988 | } | |
989 | ||
990 | static struct notifier_block cpucache_notifier = { &cpuup_callback, NULL, 0 }; | |
991 | ||
e498be7d CL |
992 | /* |
993 | * swap the static kmem_list3 with kmalloced memory | |
994 | */ | |
b28a02de | 995 | static void init_list(kmem_cache_t *cachep, struct kmem_list3 *list, int nodeid) |
e498be7d CL |
996 | { |
997 | struct kmem_list3 *ptr; | |
998 | ||
999 | BUG_ON(cachep->nodelists[nodeid] != list); | |
1000 | ptr = kmalloc_node(sizeof(struct kmem_list3), GFP_KERNEL, nodeid); | |
1001 | BUG_ON(!ptr); | |
1002 | ||
1003 | local_irq_disable(); | |
1004 | memcpy(ptr, list, sizeof(struct kmem_list3)); | |
1005 | MAKE_ALL_LISTS(cachep, ptr, nodeid); | |
1006 | cachep->nodelists[nodeid] = ptr; | |
1007 | local_irq_enable(); | |
1008 | } | |
1009 | ||
1da177e4 LT |
1010 | /* Initialisation. |
1011 | * Called after the gfp() functions have been enabled, and before smp_init(). | |
1012 | */ | |
1013 | void __init kmem_cache_init(void) | |
1014 | { | |
1015 | size_t left_over; | |
1016 | struct cache_sizes *sizes; | |
1017 | struct cache_names *names; | |
e498be7d CL |
1018 | int i; |
1019 | ||
1020 | for (i = 0; i < NUM_INIT_LISTS; i++) { | |
1021 | kmem_list3_init(&initkmem_list3[i]); | |
1022 | if (i < MAX_NUMNODES) | |
1023 | cache_cache.nodelists[i] = NULL; | |
1024 | } | |
1da177e4 LT |
1025 | |
1026 | /* | |
1027 | * Fragmentation resistance on low memory - only use bigger | |
1028 | * page orders on machines with more than 32MB of memory. | |
1029 | */ | |
1030 | if (num_physpages > (32 << 20) >> PAGE_SHIFT) | |
1031 | slab_break_gfp_order = BREAK_GFP_ORDER_HI; | |
1032 | ||
1da177e4 LT |
1033 | /* Bootstrap is tricky, because several objects are allocated |
1034 | * from caches that do not exist yet: | |
1035 | * 1) initialize the cache_cache cache: it contains the kmem_cache_t | |
1036 | * structures of all caches, except cache_cache itself: cache_cache | |
1037 | * is statically allocated. | |
e498be7d CL |
1038 | * Initially an __init data area is used for the head array and the |
1039 | * kmem_list3 structures, it's replaced with a kmalloc allocated | |
1040 | * array at the end of the bootstrap. | |
1da177e4 | 1041 | * 2) Create the first kmalloc cache. |
e498be7d CL |
1042 | * The kmem_cache_t for the new cache is allocated normally. |
1043 | * An __init data area is used for the head array. | |
1044 | * 3) Create the remaining kmalloc caches, with minimally sized | |
1045 | * head arrays. | |
1da177e4 LT |
1046 | * 4) Replace the __init data head arrays for cache_cache and the first |
1047 | * kmalloc cache with kmalloc allocated arrays. | |
e498be7d CL |
1048 | * 5) Replace the __init data for kmem_list3 for cache_cache and |
1049 | * the other cache's with kmalloc allocated memory. | |
1050 | * 6) Resize the head arrays of the kmalloc caches to their final sizes. | |
1da177e4 LT |
1051 | */ |
1052 | ||
1053 | /* 1) create the cache_cache */ | |
1da177e4 LT |
1054 | INIT_LIST_HEAD(&cache_chain); |
1055 | list_add(&cache_cache.next, &cache_chain); | |
1056 | cache_cache.colour_off = cache_line_size(); | |
1057 | cache_cache.array[smp_processor_id()] = &initarray_cache.cache; | |
e498be7d | 1058 | cache_cache.nodelists[numa_node_id()] = &initkmem_list3[CACHE_CACHE]; |
1da177e4 LT |
1059 | |
1060 | cache_cache.objsize = ALIGN(cache_cache.objsize, cache_line_size()); | |
1061 | ||
1062 | cache_estimate(0, cache_cache.objsize, cache_line_size(), 0, | |
b28a02de | 1063 | &left_over, &cache_cache.num); |
1da177e4 LT |
1064 | if (!cache_cache.num) |
1065 | BUG(); | |
1066 | ||
b28a02de | 1067 | cache_cache.colour = left_over / cache_cache.colour_off; |
1da177e4 | 1068 | cache_cache.colour_next = 0; |
b28a02de PE |
1069 | cache_cache.slab_size = ALIGN(cache_cache.num * sizeof(kmem_bufctl_t) + |
1070 | sizeof(struct slab), cache_line_size()); | |
1da177e4 LT |
1071 | |
1072 | /* 2+3) create the kmalloc caches */ | |
1073 | sizes = malloc_sizes; | |
1074 | names = cache_names; | |
1075 | ||
e498be7d CL |
1076 | /* Initialize the caches that provide memory for the array cache |
1077 | * and the kmem_list3 structures first. | |
1078 | * Without this, further allocations will bug | |
1079 | */ | |
1080 | ||
1081 | sizes[INDEX_AC].cs_cachep = kmem_cache_create(names[INDEX_AC].name, | |
b28a02de PE |
1082 | sizes[INDEX_AC].cs_size, |
1083 | ARCH_KMALLOC_MINALIGN, | |
1084 | (ARCH_KMALLOC_FLAGS | | |
1085 | SLAB_PANIC), NULL, NULL); | |
e498be7d CL |
1086 | |
1087 | if (INDEX_AC != INDEX_L3) | |
1088 | sizes[INDEX_L3].cs_cachep = | |
b28a02de PE |
1089 | kmem_cache_create(names[INDEX_L3].name, |
1090 | sizes[INDEX_L3].cs_size, | |
1091 | ARCH_KMALLOC_MINALIGN, | |
1092 | (ARCH_KMALLOC_FLAGS | SLAB_PANIC), NULL, | |
1093 | NULL); | |
e498be7d | 1094 | |
1da177e4 | 1095 | while (sizes->cs_size != ULONG_MAX) { |
e498be7d CL |
1096 | /* |
1097 | * For performance, all the general caches are L1 aligned. | |
1da177e4 LT |
1098 | * This should be particularly beneficial on SMP boxes, as it |
1099 | * eliminates "false sharing". | |
1100 | * Note for systems short on memory removing the alignment will | |
e498be7d CL |
1101 | * allow tighter packing of the smaller caches. |
1102 | */ | |
b28a02de | 1103 | if (!sizes->cs_cachep) |
e498be7d | 1104 | sizes->cs_cachep = kmem_cache_create(names->name, |
b28a02de PE |
1105 | sizes->cs_size, |
1106 | ARCH_KMALLOC_MINALIGN, | |
1107 | (ARCH_KMALLOC_FLAGS | |
1108 | | SLAB_PANIC), | |
1109 | NULL, NULL); | |
1da177e4 LT |
1110 | |
1111 | /* Inc off-slab bufctl limit until the ceiling is hit. */ | |
1112 | if (!(OFF_SLAB(sizes->cs_cachep))) { | |
b28a02de | 1113 | offslab_limit = sizes->cs_size - sizeof(struct slab); |
1da177e4 LT |
1114 | offslab_limit /= sizeof(kmem_bufctl_t); |
1115 | } | |
1116 | ||
1117 | sizes->cs_dmacachep = kmem_cache_create(names->name_dma, | |
b28a02de PE |
1118 | sizes->cs_size, |
1119 | ARCH_KMALLOC_MINALIGN, | |
1120 | (ARCH_KMALLOC_FLAGS | | |
1121 | SLAB_CACHE_DMA | | |
1122 | SLAB_PANIC), NULL, | |
1123 | NULL); | |
1da177e4 LT |
1124 | |
1125 | sizes++; | |
1126 | names++; | |
1127 | } | |
1128 | /* 4) Replace the bootstrap head arrays */ | |
1129 | { | |
b28a02de | 1130 | void *ptr; |
e498be7d | 1131 | |
1da177e4 | 1132 | ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d | 1133 | |
1da177e4 LT |
1134 | local_irq_disable(); |
1135 | BUG_ON(ac_data(&cache_cache) != &initarray_cache.cache); | |
e498be7d | 1136 | memcpy(ptr, ac_data(&cache_cache), |
b28a02de | 1137 | sizeof(struct arraycache_init)); |
1da177e4 LT |
1138 | cache_cache.array[smp_processor_id()] = ptr; |
1139 | local_irq_enable(); | |
e498be7d | 1140 | |
1da177e4 | 1141 | ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d | 1142 | |
1da177e4 | 1143 | local_irq_disable(); |
e498be7d | 1144 | BUG_ON(ac_data(malloc_sizes[INDEX_AC].cs_cachep) |
b28a02de | 1145 | != &initarray_generic.cache); |
e498be7d | 1146 | memcpy(ptr, ac_data(malloc_sizes[INDEX_AC].cs_cachep), |
b28a02de | 1147 | sizeof(struct arraycache_init)); |
e498be7d | 1148 | malloc_sizes[INDEX_AC].cs_cachep->array[smp_processor_id()] = |
b28a02de | 1149 | ptr; |
1da177e4 LT |
1150 | local_irq_enable(); |
1151 | } | |
e498be7d CL |
1152 | /* 5) Replace the bootstrap kmem_list3's */ |
1153 | { | |
1154 | int node; | |
1155 | /* Replace the static kmem_list3 structures for the boot cpu */ | |
1156 | init_list(&cache_cache, &initkmem_list3[CACHE_CACHE], | |
b28a02de | 1157 | numa_node_id()); |
e498be7d CL |
1158 | |
1159 | for_each_online_node(node) { | |
1160 | init_list(malloc_sizes[INDEX_AC].cs_cachep, | |
b28a02de | 1161 | &initkmem_list3[SIZE_AC + node], node); |
e498be7d CL |
1162 | |
1163 | if (INDEX_AC != INDEX_L3) { | |
1164 | init_list(malloc_sizes[INDEX_L3].cs_cachep, | |
b28a02de PE |
1165 | &initkmem_list3[SIZE_L3 + node], |
1166 | node); | |
e498be7d CL |
1167 | } |
1168 | } | |
1169 | } | |
1da177e4 | 1170 | |
e498be7d | 1171 | /* 6) resize the head arrays to their final sizes */ |
1da177e4 LT |
1172 | { |
1173 | kmem_cache_t *cachep; | |
fc0abb14 | 1174 | mutex_lock(&cache_chain_mutex); |
1da177e4 | 1175 | list_for_each_entry(cachep, &cache_chain, next) |
b28a02de | 1176 | enable_cpucache(cachep); |
fc0abb14 | 1177 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1178 | } |
1179 | ||
1180 | /* Done! */ | |
1181 | g_cpucache_up = FULL; | |
1182 | ||
1183 | /* Register a cpu startup notifier callback | |
1184 | * that initializes ac_data for all new cpus | |
1185 | */ | |
1186 | register_cpu_notifier(&cpucache_notifier); | |
1da177e4 LT |
1187 | |
1188 | /* The reap timers are started later, with a module init call: | |
1189 | * That part of the kernel is not yet operational. | |
1190 | */ | |
1191 | } | |
1192 | ||
1193 | static int __init cpucache_init(void) | |
1194 | { | |
1195 | int cpu; | |
1196 | ||
1197 | /* | |
1198 | * Register the timers that return unneeded | |
1199 | * pages to gfp. | |
1200 | */ | |
e498be7d | 1201 | for_each_online_cpu(cpu) |
b28a02de | 1202 | start_cpu_timer(cpu); |
1da177e4 LT |
1203 | |
1204 | return 0; | |
1205 | } | |
1206 | ||
1207 | __initcall(cpucache_init); | |
1208 | ||
1209 | /* | |
1210 | * Interface to system's page allocator. No need to hold the cache-lock. | |
1211 | * | |
1212 | * If we requested dmaable memory, we will get it. Even if we | |
1213 | * did not request dmaable memory, we might get it, but that | |
1214 | * would be relatively rare and ignorable. | |
1215 | */ | |
dd0fc66f | 1216 | static void *kmem_getpages(kmem_cache_t *cachep, gfp_t flags, int nodeid) |
1da177e4 LT |
1217 | { |
1218 | struct page *page; | |
1219 | void *addr; | |
1220 | int i; | |
1221 | ||
1222 | flags |= cachep->gfpflags; | |
50c85a19 | 1223 | page = alloc_pages_node(nodeid, flags, cachep->gfporder); |
1da177e4 LT |
1224 | if (!page) |
1225 | return NULL; | |
1226 | addr = page_address(page); | |
1227 | ||
1228 | i = (1 << cachep->gfporder); | |
1229 | if (cachep->flags & SLAB_RECLAIM_ACCOUNT) | |
1230 | atomic_add(i, &slab_reclaim_pages); | |
1231 | add_page_state(nr_slab, i); | |
1232 | while (i--) { | |
1233 | SetPageSlab(page); | |
1234 | page++; | |
1235 | } | |
1236 | return addr; | |
1237 | } | |
1238 | ||
1239 | /* | |
1240 | * Interface to system's page release. | |
1241 | */ | |
1242 | static void kmem_freepages(kmem_cache_t *cachep, void *addr) | |
1243 | { | |
b28a02de | 1244 | unsigned long i = (1 << cachep->gfporder); |
1da177e4 LT |
1245 | struct page *page = virt_to_page(addr); |
1246 | const unsigned long nr_freed = i; | |
1247 | ||
1248 | while (i--) { | |
1249 | if (!TestClearPageSlab(page)) | |
1250 | BUG(); | |
1251 | page++; | |
1252 | } | |
1253 | sub_page_state(nr_slab, nr_freed); | |
1254 | if (current->reclaim_state) | |
1255 | current->reclaim_state->reclaimed_slab += nr_freed; | |
1256 | free_pages((unsigned long)addr, cachep->gfporder); | |
b28a02de PE |
1257 | if (cachep->flags & SLAB_RECLAIM_ACCOUNT) |
1258 | atomic_sub(1 << cachep->gfporder, &slab_reclaim_pages); | |
1da177e4 LT |
1259 | } |
1260 | ||
1261 | static void kmem_rcu_free(struct rcu_head *head) | |
1262 | { | |
b28a02de | 1263 | struct slab_rcu *slab_rcu = (struct slab_rcu *)head; |
1da177e4 LT |
1264 | kmem_cache_t *cachep = slab_rcu->cachep; |
1265 | ||
1266 | kmem_freepages(cachep, slab_rcu->addr); | |
1267 | if (OFF_SLAB(cachep)) | |
1268 | kmem_cache_free(cachep->slabp_cache, slab_rcu); | |
1269 | } | |
1270 | ||
1271 | #if DEBUG | |
1272 | ||
1273 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
1274 | static void store_stackinfo(kmem_cache_t *cachep, unsigned long *addr, | |
b28a02de | 1275 | unsigned long caller) |
1da177e4 LT |
1276 | { |
1277 | int size = obj_reallen(cachep); | |
1278 | ||
b28a02de | 1279 | addr = (unsigned long *)&((char *)addr)[obj_dbghead(cachep)]; |
1da177e4 | 1280 | |
b28a02de | 1281 | if (size < 5 * sizeof(unsigned long)) |
1da177e4 LT |
1282 | return; |
1283 | ||
b28a02de PE |
1284 | *addr++ = 0x12345678; |
1285 | *addr++ = caller; | |
1286 | *addr++ = smp_processor_id(); | |
1287 | size -= 3 * sizeof(unsigned long); | |
1da177e4 LT |
1288 | { |
1289 | unsigned long *sptr = &caller; | |
1290 | unsigned long svalue; | |
1291 | ||
1292 | while (!kstack_end(sptr)) { | |
1293 | svalue = *sptr++; | |
1294 | if (kernel_text_address(svalue)) { | |
b28a02de | 1295 | *addr++ = svalue; |
1da177e4 LT |
1296 | size -= sizeof(unsigned long); |
1297 | if (size <= sizeof(unsigned long)) | |
1298 | break; | |
1299 | } | |
1300 | } | |
1301 | ||
1302 | } | |
b28a02de | 1303 | *addr++ = 0x87654321; |
1da177e4 LT |
1304 | } |
1305 | #endif | |
1306 | ||
1307 | static void poison_obj(kmem_cache_t *cachep, void *addr, unsigned char val) | |
1308 | { | |
1309 | int size = obj_reallen(cachep); | |
b28a02de | 1310 | addr = &((char *)addr)[obj_dbghead(cachep)]; |
1da177e4 LT |
1311 | |
1312 | memset(addr, val, size); | |
b28a02de | 1313 | *(unsigned char *)(addr + size - 1) = POISON_END; |
1da177e4 LT |
1314 | } |
1315 | ||
1316 | static void dump_line(char *data, int offset, int limit) | |
1317 | { | |
1318 | int i; | |
1319 | printk(KERN_ERR "%03x:", offset); | |
b28a02de PE |
1320 | for (i = 0; i < limit; i++) { |
1321 | printk(" %02x", (unsigned char)data[offset + i]); | |
1da177e4 LT |
1322 | } |
1323 | printk("\n"); | |
1324 | } | |
1325 | #endif | |
1326 | ||
1327 | #if DEBUG | |
1328 | ||
1329 | static void print_objinfo(kmem_cache_t *cachep, void *objp, int lines) | |
1330 | { | |
1331 | int i, size; | |
1332 | char *realobj; | |
1333 | ||
1334 | if (cachep->flags & SLAB_RED_ZONE) { | |
1335 | printk(KERN_ERR "Redzone: 0x%lx/0x%lx.\n", | |
b28a02de PE |
1336 | *dbg_redzone1(cachep, objp), |
1337 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
1338 | } |
1339 | ||
1340 | if (cachep->flags & SLAB_STORE_USER) { | |
1341 | printk(KERN_ERR "Last user: [<%p>]", | |
b28a02de | 1342 | *dbg_userword(cachep, objp)); |
1da177e4 | 1343 | print_symbol("(%s)", |
b28a02de | 1344 | (unsigned long)*dbg_userword(cachep, objp)); |
1da177e4 LT |
1345 | printk("\n"); |
1346 | } | |
b28a02de | 1347 | realobj = (char *)objp + obj_dbghead(cachep); |
1da177e4 | 1348 | size = obj_reallen(cachep); |
b28a02de | 1349 | for (i = 0; i < size && lines; i += 16, lines--) { |
1da177e4 LT |
1350 | int limit; |
1351 | limit = 16; | |
b28a02de PE |
1352 | if (i + limit > size) |
1353 | limit = size - i; | |
1da177e4 LT |
1354 | dump_line(realobj, i, limit); |
1355 | } | |
1356 | } | |
1357 | ||
1358 | static void check_poison_obj(kmem_cache_t *cachep, void *objp) | |
1359 | { | |
1360 | char *realobj; | |
1361 | int size, i; | |
1362 | int lines = 0; | |
1363 | ||
b28a02de | 1364 | realobj = (char *)objp + obj_dbghead(cachep); |
1da177e4 LT |
1365 | size = obj_reallen(cachep); |
1366 | ||
b28a02de | 1367 | for (i = 0; i < size; i++) { |
1da177e4 | 1368 | char exp = POISON_FREE; |
b28a02de | 1369 | if (i == size - 1) |
1da177e4 LT |
1370 | exp = POISON_END; |
1371 | if (realobj[i] != exp) { | |
1372 | int limit; | |
1373 | /* Mismatch ! */ | |
1374 | /* Print header */ | |
1375 | if (lines == 0) { | |
b28a02de PE |
1376 | printk(KERN_ERR |
1377 | "Slab corruption: start=%p, len=%d\n", | |
1378 | realobj, size); | |
1da177e4 LT |
1379 | print_objinfo(cachep, objp, 0); |
1380 | } | |
1381 | /* Hexdump the affected line */ | |
b28a02de | 1382 | i = (i / 16) * 16; |
1da177e4 | 1383 | limit = 16; |
b28a02de PE |
1384 | if (i + limit > size) |
1385 | limit = size - i; | |
1da177e4 LT |
1386 | dump_line(realobj, i, limit); |
1387 | i += 16; | |
1388 | lines++; | |
1389 | /* Limit to 5 lines */ | |
1390 | if (lines > 5) | |
1391 | break; | |
1392 | } | |
1393 | } | |
1394 | if (lines != 0) { | |
1395 | /* Print some data about the neighboring objects, if they | |
1396 | * exist: | |
1397 | */ | |
065d41cb | 1398 | struct slab *slabp = page_get_slab(virt_to_page(objp)); |
1da177e4 LT |
1399 | int objnr; |
1400 | ||
b28a02de | 1401 | objnr = (objp - slabp->s_mem) / cachep->objsize; |
1da177e4 | 1402 | if (objnr) { |
b28a02de PE |
1403 | objp = slabp->s_mem + (objnr - 1) * cachep->objsize; |
1404 | realobj = (char *)objp + obj_dbghead(cachep); | |
1da177e4 | 1405 | printk(KERN_ERR "Prev obj: start=%p, len=%d\n", |
b28a02de | 1406 | realobj, size); |
1da177e4 LT |
1407 | print_objinfo(cachep, objp, 2); |
1408 | } | |
b28a02de PE |
1409 | if (objnr + 1 < cachep->num) { |
1410 | objp = slabp->s_mem + (objnr + 1) * cachep->objsize; | |
1411 | realobj = (char *)objp + obj_dbghead(cachep); | |
1da177e4 | 1412 | printk(KERN_ERR "Next obj: start=%p, len=%d\n", |
b28a02de | 1413 | realobj, size); |
1da177e4 LT |
1414 | print_objinfo(cachep, objp, 2); |
1415 | } | |
1416 | } | |
1417 | } | |
1418 | #endif | |
1419 | ||
1420 | /* Destroy all the objs in a slab, and release the mem back to the system. | |
1421 | * Before calling the slab must have been unlinked from the cache. | |
1422 | * The cache-lock is not held/needed. | |
1423 | */ | |
b28a02de | 1424 | static void slab_destroy(kmem_cache_t *cachep, struct slab *slabp) |
1da177e4 LT |
1425 | { |
1426 | void *addr = slabp->s_mem - slabp->colouroff; | |
1427 | ||
1428 | #if DEBUG | |
1429 | int i; | |
1430 | for (i = 0; i < cachep->num; i++) { | |
1431 | void *objp = slabp->s_mem + cachep->objsize * i; | |
1432 | ||
1433 | if (cachep->flags & SLAB_POISON) { | |
1434 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
b28a02de PE |
1435 | if ((cachep->objsize % PAGE_SIZE) == 0 |
1436 | && OFF_SLAB(cachep)) | |
1437 | kernel_map_pages(virt_to_page(objp), | |
1438 | cachep->objsize / PAGE_SIZE, | |
1439 | 1); | |
1da177e4 LT |
1440 | else |
1441 | check_poison_obj(cachep, objp); | |
1442 | #else | |
1443 | check_poison_obj(cachep, objp); | |
1444 | #endif | |
1445 | } | |
1446 | if (cachep->flags & SLAB_RED_ZONE) { | |
1447 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) | |
1448 | slab_error(cachep, "start of a freed object " | |
b28a02de | 1449 | "was overwritten"); |
1da177e4 LT |
1450 | if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) |
1451 | slab_error(cachep, "end of a freed object " | |
b28a02de | 1452 | "was overwritten"); |
1da177e4 LT |
1453 | } |
1454 | if (cachep->dtor && !(cachep->flags & SLAB_POISON)) | |
b28a02de | 1455 | (cachep->dtor) (objp + obj_dbghead(cachep), cachep, 0); |
1da177e4 LT |
1456 | } |
1457 | #else | |
1458 | if (cachep->dtor) { | |
1459 | int i; | |
1460 | for (i = 0; i < cachep->num; i++) { | |
b28a02de PE |
1461 | void *objp = slabp->s_mem + cachep->objsize * i; |
1462 | (cachep->dtor) (objp, cachep, 0); | |
1da177e4 LT |
1463 | } |
1464 | } | |
1465 | #endif | |
1466 | ||
1467 | if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) { | |
1468 | struct slab_rcu *slab_rcu; | |
1469 | ||
b28a02de | 1470 | slab_rcu = (struct slab_rcu *)slabp; |
1da177e4 LT |
1471 | slab_rcu->cachep = cachep; |
1472 | slab_rcu->addr = addr; | |
1473 | call_rcu(&slab_rcu->head, kmem_rcu_free); | |
1474 | } else { | |
1475 | kmem_freepages(cachep, addr); | |
1476 | if (OFF_SLAB(cachep)) | |
1477 | kmem_cache_free(cachep->slabp_cache, slabp); | |
1478 | } | |
1479 | } | |
1480 | ||
e498be7d CL |
1481 | /* For setting up all the kmem_list3s for cache whose objsize is same |
1482 | as size of kmem_list3. */ | |
1483 | static inline void set_up_list3s(kmem_cache_t *cachep, int index) | |
1484 | { | |
1485 | int node; | |
1486 | ||
1487 | for_each_online_node(node) { | |
b28a02de | 1488 | cachep->nodelists[node] = &initkmem_list3[index + node]; |
e498be7d | 1489 | cachep->nodelists[node]->next_reap = jiffies + |
b28a02de PE |
1490 | REAPTIMEOUT_LIST3 + |
1491 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; | |
e498be7d CL |
1492 | } |
1493 | } | |
1494 | ||
4d268eba PE |
1495 | /** |
1496 | * calculate_slab_order - calculate size (page order) of slabs and the number | |
1497 | * of objects per slab. | |
1498 | * | |
1499 | * This could be made much more intelligent. For now, try to avoid using | |
1500 | * high order pages for slabs. When the gfp() functions are more friendly | |
1501 | * towards high-order requests, this should be changed. | |
1502 | */ | |
1503 | static inline size_t calculate_slab_order(kmem_cache_t *cachep, size_t size, | |
1504 | size_t align, gfp_t flags) | |
1505 | { | |
1506 | size_t left_over = 0; | |
1507 | ||
b28a02de | 1508 | for (;; cachep->gfporder++) { |
4d268eba PE |
1509 | unsigned int num; |
1510 | size_t remainder; | |
1511 | ||
1512 | if (cachep->gfporder > MAX_GFP_ORDER) { | |
1513 | cachep->num = 0; | |
1514 | break; | |
1515 | } | |
1516 | ||
1517 | cache_estimate(cachep->gfporder, size, align, flags, | |
1518 | &remainder, &num); | |
1519 | if (!num) | |
1520 | continue; | |
1521 | /* More than offslab_limit objects will cause problems */ | |
1522 | if (flags & CFLGS_OFF_SLAB && cachep->num > offslab_limit) | |
1523 | break; | |
1524 | ||
1525 | cachep->num = num; | |
1526 | left_over = remainder; | |
1527 | ||
1528 | /* | |
1529 | * Large number of objects is good, but very large slabs are | |
1530 | * currently bad for the gfp()s. | |
1531 | */ | |
1532 | if (cachep->gfporder >= slab_break_gfp_order) | |
1533 | break; | |
1534 | ||
1535 | if ((left_over * 8) <= (PAGE_SIZE << cachep->gfporder)) | |
1536 | /* Acceptable internal fragmentation */ | |
1537 | break; | |
1538 | } | |
1539 | return left_over; | |
1540 | } | |
1541 | ||
1da177e4 LT |
1542 | /** |
1543 | * kmem_cache_create - Create a cache. | |
1544 | * @name: A string which is used in /proc/slabinfo to identify this cache. | |
1545 | * @size: The size of objects to be created in this cache. | |
1546 | * @align: The required alignment for the objects. | |
1547 | * @flags: SLAB flags | |
1548 | * @ctor: A constructor for the objects. | |
1549 | * @dtor: A destructor for the objects. | |
1550 | * | |
1551 | * Returns a ptr to the cache on success, NULL on failure. | |
1552 | * Cannot be called within a int, but can be interrupted. | |
1553 | * The @ctor is run when new pages are allocated by the cache | |
1554 | * and the @dtor is run before the pages are handed back. | |
1555 | * | |
1556 | * @name must be valid until the cache is destroyed. This implies that | |
1557 | * the module calling this has to destroy the cache before getting | |
1558 | * unloaded. | |
1559 | * | |
1560 | * The flags are | |
1561 | * | |
1562 | * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5) | |
1563 | * to catch references to uninitialised memory. | |
1564 | * | |
1565 | * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check | |
1566 | * for buffer overruns. | |
1567 | * | |
1568 | * %SLAB_NO_REAP - Don't automatically reap this cache when we're under | |
1569 | * memory pressure. | |
1570 | * | |
1571 | * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware | |
1572 | * cacheline. This can be beneficial if you're counting cycles as closely | |
1573 | * as davem. | |
1574 | */ | |
1575 | kmem_cache_t * | |
1576 | kmem_cache_create (const char *name, size_t size, size_t align, | |
1577 | unsigned long flags, void (*ctor)(void*, kmem_cache_t *, unsigned long), | |
1578 | void (*dtor)(void*, kmem_cache_t *, unsigned long)) | |
1579 | { | |
1580 | size_t left_over, slab_size, ralign; | |
1581 | kmem_cache_t *cachep = NULL; | |
4f12bb4f | 1582 | struct list_head *p; |
1da177e4 LT |
1583 | |
1584 | /* | |
1585 | * Sanity checks... these are all serious usage bugs. | |
1586 | */ | |
1587 | if ((!name) || | |
b28a02de PE |
1588 | in_interrupt() || |
1589 | (size < BYTES_PER_WORD) || | |
1590 | (size > (1 << MAX_OBJ_ORDER) * PAGE_SIZE) || (dtor && !ctor)) { | |
1591 | printk(KERN_ERR "%s: Early error in slab %s\n", | |
1592 | __FUNCTION__, name); | |
1593 | BUG(); | |
1594 | } | |
1da177e4 | 1595 | |
fc0abb14 | 1596 | mutex_lock(&cache_chain_mutex); |
4f12bb4f AM |
1597 | |
1598 | list_for_each(p, &cache_chain) { | |
1599 | kmem_cache_t *pc = list_entry(p, kmem_cache_t, next); | |
1600 | mm_segment_t old_fs = get_fs(); | |
1601 | char tmp; | |
1602 | int res; | |
1603 | ||
1604 | /* | |
1605 | * This happens when the module gets unloaded and doesn't | |
1606 | * destroy its slab cache and no-one else reuses the vmalloc | |
1607 | * area of the module. Print a warning. | |
1608 | */ | |
1609 | set_fs(KERNEL_DS); | |
1610 | res = __get_user(tmp, pc->name); | |
1611 | set_fs(old_fs); | |
1612 | if (res) { | |
1613 | printk("SLAB: cache with size %d has lost its name\n", | |
b28a02de | 1614 | pc->objsize); |
4f12bb4f AM |
1615 | continue; |
1616 | } | |
1617 | ||
b28a02de | 1618 | if (!strcmp(pc->name, name)) { |
4f12bb4f AM |
1619 | printk("kmem_cache_create: duplicate cache %s\n", name); |
1620 | dump_stack(); | |
1621 | goto oops; | |
1622 | } | |
1623 | } | |
1624 | ||
1da177e4 LT |
1625 | #if DEBUG |
1626 | WARN_ON(strchr(name, ' ')); /* It confuses parsers */ | |
1627 | if ((flags & SLAB_DEBUG_INITIAL) && !ctor) { | |
1628 | /* No constructor, but inital state check requested */ | |
1629 | printk(KERN_ERR "%s: No con, but init state check " | |
b28a02de | 1630 | "requested - %s\n", __FUNCTION__, name); |
1da177e4 LT |
1631 | flags &= ~SLAB_DEBUG_INITIAL; |
1632 | } | |
1da177e4 LT |
1633 | #if FORCED_DEBUG |
1634 | /* | |
1635 | * Enable redzoning and last user accounting, except for caches with | |
1636 | * large objects, if the increased size would increase the object size | |
1637 | * above the next power of two: caches with object sizes just above a | |
1638 | * power of two have a significant amount of internal fragmentation. | |
1639 | */ | |
b28a02de PE |
1640 | if ((size < 4096 |
1641 | || fls(size - 1) == fls(size - 1 + 3 * BYTES_PER_WORD))) | |
1642 | flags |= SLAB_RED_ZONE | SLAB_STORE_USER; | |
1da177e4 LT |
1643 | if (!(flags & SLAB_DESTROY_BY_RCU)) |
1644 | flags |= SLAB_POISON; | |
1645 | #endif | |
1646 | if (flags & SLAB_DESTROY_BY_RCU) | |
1647 | BUG_ON(flags & SLAB_POISON); | |
1648 | #endif | |
1649 | if (flags & SLAB_DESTROY_BY_RCU) | |
1650 | BUG_ON(dtor); | |
1651 | ||
1652 | /* | |
1653 | * Always checks flags, a caller might be expecting debug | |
1654 | * support which isn't available. | |
1655 | */ | |
1656 | if (flags & ~CREATE_MASK) | |
1657 | BUG(); | |
1658 | ||
1659 | /* Check that size is in terms of words. This is needed to avoid | |
1660 | * unaligned accesses for some archs when redzoning is used, and makes | |
1661 | * sure any on-slab bufctl's are also correctly aligned. | |
1662 | */ | |
b28a02de PE |
1663 | if (size & (BYTES_PER_WORD - 1)) { |
1664 | size += (BYTES_PER_WORD - 1); | |
1665 | size &= ~(BYTES_PER_WORD - 1); | |
1da177e4 LT |
1666 | } |
1667 | ||
1668 | /* calculate out the final buffer alignment: */ | |
1669 | /* 1) arch recommendation: can be overridden for debug */ | |
1670 | if (flags & SLAB_HWCACHE_ALIGN) { | |
1671 | /* Default alignment: as specified by the arch code. | |
1672 | * Except if an object is really small, then squeeze multiple | |
1673 | * objects into one cacheline. | |
1674 | */ | |
1675 | ralign = cache_line_size(); | |
b28a02de | 1676 | while (size <= ralign / 2) |
1da177e4 LT |
1677 | ralign /= 2; |
1678 | } else { | |
1679 | ralign = BYTES_PER_WORD; | |
1680 | } | |
1681 | /* 2) arch mandated alignment: disables debug if necessary */ | |
1682 | if (ralign < ARCH_SLAB_MINALIGN) { | |
1683 | ralign = ARCH_SLAB_MINALIGN; | |
1684 | if (ralign > BYTES_PER_WORD) | |
b28a02de | 1685 | flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
1da177e4 LT |
1686 | } |
1687 | /* 3) caller mandated alignment: disables debug if necessary */ | |
1688 | if (ralign < align) { | |
1689 | ralign = align; | |
1690 | if (ralign > BYTES_PER_WORD) | |
b28a02de | 1691 | flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER); |
1da177e4 LT |
1692 | } |
1693 | /* 4) Store it. Note that the debug code below can reduce | |
1694 | * the alignment to BYTES_PER_WORD. | |
1695 | */ | |
1696 | align = ralign; | |
1697 | ||
1698 | /* Get cache's description obj. */ | |
1699 | cachep = (kmem_cache_t *) kmem_cache_alloc(&cache_cache, SLAB_KERNEL); | |
1700 | if (!cachep) | |
4f12bb4f | 1701 | goto oops; |
1da177e4 LT |
1702 | memset(cachep, 0, sizeof(kmem_cache_t)); |
1703 | ||
1704 | #if DEBUG | |
1705 | cachep->reallen = size; | |
1706 | ||
1707 | if (flags & SLAB_RED_ZONE) { | |
1708 | /* redzoning only works with word aligned caches */ | |
1709 | align = BYTES_PER_WORD; | |
1710 | ||
1711 | /* add space for red zone words */ | |
1712 | cachep->dbghead += BYTES_PER_WORD; | |
b28a02de | 1713 | size += 2 * BYTES_PER_WORD; |
1da177e4 LT |
1714 | } |
1715 | if (flags & SLAB_STORE_USER) { | |
1716 | /* user store requires word alignment and | |
1717 | * one word storage behind the end of the real | |
1718 | * object. | |
1719 | */ | |
1720 | align = BYTES_PER_WORD; | |
1721 | size += BYTES_PER_WORD; | |
1722 | } | |
1723 | #if FORCED_DEBUG && defined(CONFIG_DEBUG_PAGEALLOC) | |
b28a02de PE |
1724 | if (size >= malloc_sizes[INDEX_L3 + 1].cs_size |
1725 | && cachep->reallen > cache_line_size() && size < PAGE_SIZE) { | |
1da177e4 LT |
1726 | cachep->dbghead += PAGE_SIZE - size; |
1727 | size = PAGE_SIZE; | |
1728 | } | |
1729 | #endif | |
1730 | #endif | |
1731 | ||
1732 | /* Determine if the slab management is 'on' or 'off' slab. */ | |
b28a02de | 1733 | if (size >= (PAGE_SIZE >> 3)) |
1da177e4 LT |
1734 | /* |
1735 | * Size is large, assume best to place the slab management obj | |
1736 | * off-slab (should allow better packing of objs). | |
1737 | */ | |
1738 | flags |= CFLGS_OFF_SLAB; | |
1739 | ||
1740 | size = ALIGN(size, align); | |
1741 | ||
1742 | if ((flags & SLAB_RECLAIM_ACCOUNT) && size <= PAGE_SIZE) { | |
1743 | /* | |
1744 | * A VFS-reclaimable slab tends to have most allocations | |
1745 | * as GFP_NOFS and we really don't want to have to be allocating | |
1746 | * higher-order pages when we are unable to shrink dcache. | |
1747 | */ | |
1748 | cachep->gfporder = 0; | |
1749 | cache_estimate(cachep->gfporder, size, align, flags, | |
b28a02de | 1750 | &left_over, &cachep->num); |
4d268eba PE |
1751 | } else |
1752 | left_over = calculate_slab_order(cachep, size, align, flags); | |
1da177e4 LT |
1753 | |
1754 | if (!cachep->num) { | |
1755 | printk("kmem_cache_create: couldn't create cache %s.\n", name); | |
1756 | kmem_cache_free(&cache_cache, cachep); | |
1757 | cachep = NULL; | |
4f12bb4f | 1758 | goto oops; |
1da177e4 | 1759 | } |
b28a02de PE |
1760 | slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t) |
1761 | + sizeof(struct slab), align); | |
1da177e4 LT |
1762 | |
1763 | /* | |
1764 | * If the slab has been placed off-slab, and we have enough space then | |
1765 | * move it on-slab. This is at the expense of any extra colouring. | |
1766 | */ | |
1767 | if (flags & CFLGS_OFF_SLAB && left_over >= slab_size) { | |
1768 | flags &= ~CFLGS_OFF_SLAB; | |
1769 | left_over -= slab_size; | |
1770 | } | |
1771 | ||
1772 | if (flags & CFLGS_OFF_SLAB) { | |
1773 | /* really off slab. No need for manual alignment */ | |
b28a02de PE |
1774 | slab_size = |
1775 | cachep->num * sizeof(kmem_bufctl_t) + sizeof(struct slab); | |
1da177e4 LT |
1776 | } |
1777 | ||
1778 | cachep->colour_off = cache_line_size(); | |
1779 | /* Offset must be a multiple of the alignment. */ | |
1780 | if (cachep->colour_off < align) | |
1781 | cachep->colour_off = align; | |
b28a02de | 1782 | cachep->colour = left_over / cachep->colour_off; |
1da177e4 LT |
1783 | cachep->slab_size = slab_size; |
1784 | cachep->flags = flags; | |
1785 | cachep->gfpflags = 0; | |
1786 | if (flags & SLAB_CACHE_DMA) | |
1787 | cachep->gfpflags |= GFP_DMA; | |
1788 | spin_lock_init(&cachep->spinlock); | |
1789 | cachep->objsize = size; | |
1da177e4 LT |
1790 | |
1791 | if (flags & CFLGS_OFF_SLAB) | |
b2d55073 | 1792 | cachep->slabp_cache = kmem_find_general_cachep(slab_size, 0u); |
1da177e4 LT |
1793 | cachep->ctor = ctor; |
1794 | cachep->dtor = dtor; | |
1795 | cachep->name = name; | |
1796 | ||
1797 | /* Don't let CPUs to come and go */ | |
1798 | lock_cpu_hotplug(); | |
1799 | ||
1800 | if (g_cpucache_up == FULL) { | |
1801 | enable_cpucache(cachep); | |
1802 | } else { | |
1803 | if (g_cpucache_up == NONE) { | |
1804 | /* Note: the first kmem_cache_create must create | |
1805 | * the cache that's used by kmalloc(24), otherwise | |
1806 | * the creation of further caches will BUG(). | |
1807 | */ | |
e498be7d | 1808 | cachep->array[smp_processor_id()] = |
b28a02de | 1809 | &initarray_generic.cache; |
e498be7d CL |
1810 | |
1811 | /* If the cache that's used by | |
1812 | * kmalloc(sizeof(kmem_list3)) is the first cache, | |
1813 | * then we need to set up all its list3s, otherwise | |
1814 | * the creation of further caches will BUG(). | |
1815 | */ | |
1816 | set_up_list3s(cachep, SIZE_AC); | |
1817 | if (INDEX_AC == INDEX_L3) | |
1818 | g_cpucache_up = PARTIAL_L3; | |
1819 | else | |
1820 | g_cpucache_up = PARTIAL_AC; | |
1da177e4 | 1821 | } else { |
e498be7d | 1822 | cachep->array[smp_processor_id()] = |
b28a02de | 1823 | kmalloc(sizeof(struct arraycache_init), GFP_KERNEL); |
e498be7d CL |
1824 | |
1825 | if (g_cpucache_up == PARTIAL_AC) { | |
1826 | set_up_list3s(cachep, SIZE_L3); | |
1827 | g_cpucache_up = PARTIAL_L3; | |
1828 | } else { | |
1829 | int node; | |
1830 | for_each_online_node(node) { | |
1831 | ||
1832 | cachep->nodelists[node] = | |
b28a02de PE |
1833 | kmalloc_node(sizeof |
1834 | (struct kmem_list3), | |
1835 | GFP_KERNEL, node); | |
e498be7d | 1836 | BUG_ON(!cachep->nodelists[node]); |
b28a02de PE |
1837 | kmem_list3_init(cachep-> |
1838 | nodelists[node]); | |
e498be7d CL |
1839 | } |
1840 | } | |
1da177e4 | 1841 | } |
e498be7d | 1842 | cachep->nodelists[numa_node_id()]->next_reap = |
b28a02de PE |
1843 | jiffies + REAPTIMEOUT_LIST3 + |
1844 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; | |
e498be7d | 1845 | |
1da177e4 LT |
1846 | BUG_ON(!ac_data(cachep)); |
1847 | ac_data(cachep)->avail = 0; | |
1848 | ac_data(cachep)->limit = BOOT_CPUCACHE_ENTRIES; | |
1849 | ac_data(cachep)->batchcount = 1; | |
1850 | ac_data(cachep)->touched = 0; | |
1851 | cachep->batchcount = 1; | |
1852 | cachep->limit = BOOT_CPUCACHE_ENTRIES; | |
b28a02de | 1853 | } |
1da177e4 | 1854 | |
1da177e4 LT |
1855 | /* cache setup completed, link it into the list */ |
1856 | list_add(&cachep->next, &cache_chain); | |
1da177e4 | 1857 | unlock_cpu_hotplug(); |
b28a02de | 1858 | oops: |
1da177e4 LT |
1859 | if (!cachep && (flags & SLAB_PANIC)) |
1860 | panic("kmem_cache_create(): failed to create slab `%s'\n", | |
b28a02de | 1861 | name); |
fc0abb14 | 1862 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
1863 | return cachep; |
1864 | } | |
1865 | EXPORT_SYMBOL(kmem_cache_create); | |
1866 | ||
1867 | #if DEBUG | |
1868 | static void check_irq_off(void) | |
1869 | { | |
1870 | BUG_ON(!irqs_disabled()); | |
1871 | } | |
1872 | ||
1873 | static void check_irq_on(void) | |
1874 | { | |
1875 | BUG_ON(irqs_disabled()); | |
1876 | } | |
1877 | ||
1878 | static void check_spinlock_acquired(kmem_cache_t *cachep) | |
1879 | { | |
1880 | #ifdef CONFIG_SMP | |
1881 | check_irq_off(); | |
e498be7d | 1882 | assert_spin_locked(&cachep->nodelists[numa_node_id()]->list_lock); |
1da177e4 LT |
1883 | #endif |
1884 | } | |
e498be7d CL |
1885 | |
1886 | static inline void check_spinlock_acquired_node(kmem_cache_t *cachep, int node) | |
1887 | { | |
1888 | #ifdef CONFIG_SMP | |
1889 | check_irq_off(); | |
1890 | assert_spin_locked(&cachep->nodelists[node]->list_lock); | |
1891 | #endif | |
1892 | } | |
1893 | ||
1da177e4 LT |
1894 | #else |
1895 | #define check_irq_off() do { } while(0) | |
1896 | #define check_irq_on() do { } while(0) | |
1897 | #define check_spinlock_acquired(x) do { } while(0) | |
e498be7d | 1898 | #define check_spinlock_acquired_node(x, y) do { } while(0) |
1da177e4 LT |
1899 | #endif |
1900 | ||
1901 | /* | |
1902 | * Waits for all CPUs to execute func(). | |
1903 | */ | |
b28a02de | 1904 | static void smp_call_function_all_cpus(void (*func)(void *arg), void *arg) |
1da177e4 LT |
1905 | { |
1906 | check_irq_on(); | |
1907 | preempt_disable(); | |
1908 | ||
1909 | local_irq_disable(); | |
1910 | func(arg); | |
1911 | local_irq_enable(); | |
1912 | ||
1913 | if (smp_call_function(func, arg, 1, 1)) | |
1914 | BUG(); | |
1915 | ||
1916 | preempt_enable(); | |
1917 | } | |
1918 | ||
b28a02de PE |
1919 | static void drain_array_locked(kmem_cache_t *cachep, struct array_cache *ac, |
1920 | int force, int node); | |
1da177e4 LT |
1921 | |
1922 | static void do_drain(void *arg) | |
1923 | { | |
b28a02de | 1924 | kmem_cache_t *cachep = (kmem_cache_t *) arg; |
1da177e4 | 1925 | struct array_cache *ac; |
ff69416e | 1926 | int node = numa_node_id(); |
1da177e4 LT |
1927 | |
1928 | check_irq_off(); | |
1929 | ac = ac_data(cachep); | |
ff69416e CL |
1930 | spin_lock(&cachep->nodelists[node]->list_lock); |
1931 | free_block(cachep, ac->entry, ac->avail, node); | |
1932 | spin_unlock(&cachep->nodelists[node]->list_lock); | |
1da177e4 LT |
1933 | ac->avail = 0; |
1934 | } | |
1935 | ||
1936 | static void drain_cpu_caches(kmem_cache_t *cachep) | |
1937 | { | |
e498be7d CL |
1938 | struct kmem_list3 *l3; |
1939 | int node; | |
1940 | ||
1da177e4 LT |
1941 | smp_call_function_all_cpus(do_drain, cachep); |
1942 | check_irq_on(); | |
1943 | spin_lock_irq(&cachep->spinlock); | |
b28a02de | 1944 | for_each_online_node(node) { |
e498be7d CL |
1945 | l3 = cachep->nodelists[node]; |
1946 | if (l3) { | |
1947 | spin_lock(&l3->list_lock); | |
1948 | drain_array_locked(cachep, l3->shared, 1, node); | |
1949 | spin_unlock(&l3->list_lock); | |
1950 | if (l3->alien) | |
1951 | drain_alien_cache(cachep, l3); | |
1952 | } | |
1953 | } | |
1da177e4 LT |
1954 | spin_unlock_irq(&cachep->spinlock); |
1955 | } | |
1956 | ||
e498be7d | 1957 | static int __node_shrink(kmem_cache_t *cachep, int node) |
1da177e4 LT |
1958 | { |
1959 | struct slab *slabp; | |
e498be7d | 1960 | struct kmem_list3 *l3 = cachep->nodelists[node]; |
1da177e4 LT |
1961 | int ret; |
1962 | ||
e498be7d | 1963 | for (;;) { |
1da177e4 LT |
1964 | struct list_head *p; |
1965 | ||
e498be7d CL |
1966 | p = l3->slabs_free.prev; |
1967 | if (p == &l3->slabs_free) | |
1da177e4 LT |
1968 | break; |
1969 | ||
e498be7d | 1970 | slabp = list_entry(l3->slabs_free.prev, struct slab, list); |
1da177e4 LT |
1971 | #if DEBUG |
1972 | if (slabp->inuse) | |
1973 | BUG(); | |
1974 | #endif | |
1975 | list_del(&slabp->list); | |
1976 | ||
e498be7d CL |
1977 | l3->free_objects -= cachep->num; |
1978 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 1979 | slab_destroy(cachep, slabp); |
e498be7d | 1980 | spin_lock_irq(&l3->list_lock); |
1da177e4 | 1981 | } |
b28a02de | 1982 | ret = !list_empty(&l3->slabs_full) || !list_empty(&l3->slabs_partial); |
1da177e4 LT |
1983 | return ret; |
1984 | } | |
1985 | ||
e498be7d CL |
1986 | static int __cache_shrink(kmem_cache_t *cachep) |
1987 | { | |
1988 | int ret = 0, i = 0; | |
1989 | struct kmem_list3 *l3; | |
1990 | ||
1991 | drain_cpu_caches(cachep); | |
1992 | ||
1993 | check_irq_on(); | |
1994 | for_each_online_node(i) { | |
1995 | l3 = cachep->nodelists[i]; | |
1996 | if (l3) { | |
1997 | spin_lock_irq(&l3->list_lock); | |
1998 | ret += __node_shrink(cachep, i); | |
1999 | spin_unlock_irq(&l3->list_lock); | |
2000 | } | |
2001 | } | |
2002 | return (ret ? 1 : 0); | |
2003 | } | |
2004 | ||
1da177e4 LT |
2005 | /** |
2006 | * kmem_cache_shrink - Shrink a cache. | |
2007 | * @cachep: The cache to shrink. | |
2008 | * | |
2009 | * Releases as many slabs as possible for a cache. | |
2010 | * To help debugging, a zero exit status indicates all slabs were released. | |
2011 | */ | |
2012 | int kmem_cache_shrink(kmem_cache_t *cachep) | |
2013 | { | |
2014 | if (!cachep || in_interrupt()) | |
2015 | BUG(); | |
2016 | ||
2017 | return __cache_shrink(cachep); | |
2018 | } | |
2019 | EXPORT_SYMBOL(kmem_cache_shrink); | |
2020 | ||
2021 | /** | |
2022 | * kmem_cache_destroy - delete a cache | |
2023 | * @cachep: the cache to destroy | |
2024 | * | |
2025 | * Remove a kmem_cache_t object from the slab cache. | |
2026 | * Returns 0 on success. | |
2027 | * | |
2028 | * It is expected this function will be called by a module when it is | |
2029 | * unloaded. This will remove the cache completely, and avoid a duplicate | |
2030 | * cache being allocated each time a module is loaded and unloaded, if the | |
2031 | * module doesn't have persistent in-kernel storage across loads and unloads. | |
2032 | * | |
2033 | * The cache must be empty before calling this function. | |
2034 | * | |
2035 | * The caller must guarantee that noone will allocate memory from the cache | |
2036 | * during the kmem_cache_destroy(). | |
2037 | */ | |
b28a02de | 2038 | int kmem_cache_destroy(kmem_cache_t *cachep) |
1da177e4 LT |
2039 | { |
2040 | int i; | |
e498be7d | 2041 | struct kmem_list3 *l3; |
1da177e4 LT |
2042 | |
2043 | if (!cachep || in_interrupt()) | |
2044 | BUG(); | |
2045 | ||
2046 | /* Don't let CPUs to come and go */ | |
2047 | lock_cpu_hotplug(); | |
2048 | ||
2049 | /* Find the cache in the chain of caches. */ | |
fc0abb14 | 2050 | mutex_lock(&cache_chain_mutex); |
1da177e4 LT |
2051 | /* |
2052 | * the chain is never empty, cache_cache is never destroyed | |
2053 | */ | |
2054 | list_del(&cachep->next); | |
fc0abb14 | 2055 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
2056 | |
2057 | if (__cache_shrink(cachep)) { | |
2058 | slab_error(cachep, "Can't free all objects"); | |
fc0abb14 | 2059 | mutex_lock(&cache_chain_mutex); |
b28a02de | 2060 | list_add(&cachep->next, &cache_chain); |
fc0abb14 | 2061 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
2062 | unlock_cpu_hotplug(); |
2063 | return 1; | |
2064 | } | |
2065 | ||
2066 | if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) | |
fbd568a3 | 2067 | synchronize_rcu(); |
1da177e4 | 2068 | |
e498be7d | 2069 | for_each_online_cpu(i) |
b28a02de | 2070 | kfree(cachep->array[i]); |
1da177e4 LT |
2071 | |
2072 | /* NUMA: free the list3 structures */ | |
e498be7d CL |
2073 | for_each_online_node(i) { |
2074 | if ((l3 = cachep->nodelists[i])) { | |
2075 | kfree(l3->shared); | |
2076 | free_alien_cache(l3->alien); | |
2077 | kfree(l3); | |
2078 | } | |
2079 | } | |
1da177e4 LT |
2080 | kmem_cache_free(&cache_cache, cachep); |
2081 | ||
2082 | unlock_cpu_hotplug(); | |
2083 | ||
2084 | return 0; | |
2085 | } | |
2086 | EXPORT_SYMBOL(kmem_cache_destroy); | |
2087 | ||
2088 | /* Get the memory for a slab management obj. */ | |
b28a02de PE |
2089 | static struct slab *alloc_slabmgmt(kmem_cache_t *cachep, void *objp, |
2090 | int colour_off, gfp_t local_flags) | |
1da177e4 LT |
2091 | { |
2092 | struct slab *slabp; | |
b28a02de | 2093 | |
1da177e4 LT |
2094 | if (OFF_SLAB(cachep)) { |
2095 | /* Slab management obj is off-slab. */ | |
2096 | slabp = kmem_cache_alloc(cachep->slabp_cache, local_flags); | |
2097 | if (!slabp) | |
2098 | return NULL; | |
2099 | } else { | |
b28a02de | 2100 | slabp = objp + colour_off; |
1da177e4 LT |
2101 | colour_off += cachep->slab_size; |
2102 | } | |
2103 | slabp->inuse = 0; | |
2104 | slabp->colouroff = colour_off; | |
b28a02de | 2105 | slabp->s_mem = objp + colour_off; |
1da177e4 LT |
2106 | |
2107 | return slabp; | |
2108 | } | |
2109 | ||
2110 | static inline kmem_bufctl_t *slab_bufctl(struct slab *slabp) | |
2111 | { | |
b28a02de | 2112 | return (kmem_bufctl_t *) (slabp + 1); |
1da177e4 LT |
2113 | } |
2114 | ||
2115 | static void cache_init_objs(kmem_cache_t *cachep, | |
b28a02de | 2116 | struct slab *slabp, unsigned long ctor_flags) |
1da177e4 LT |
2117 | { |
2118 | int i; | |
2119 | ||
2120 | for (i = 0; i < cachep->num; i++) { | |
b28a02de | 2121 | void *objp = slabp->s_mem + cachep->objsize * i; |
1da177e4 LT |
2122 | #if DEBUG |
2123 | /* need to poison the objs? */ | |
2124 | if (cachep->flags & SLAB_POISON) | |
2125 | poison_obj(cachep, objp, POISON_FREE); | |
2126 | if (cachep->flags & SLAB_STORE_USER) | |
2127 | *dbg_userword(cachep, objp) = NULL; | |
2128 | ||
2129 | if (cachep->flags & SLAB_RED_ZONE) { | |
2130 | *dbg_redzone1(cachep, objp) = RED_INACTIVE; | |
2131 | *dbg_redzone2(cachep, objp) = RED_INACTIVE; | |
2132 | } | |
2133 | /* | |
2134 | * Constructors are not allowed to allocate memory from | |
2135 | * the same cache which they are a constructor for. | |
2136 | * Otherwise, deadlock. They must also be threaded. | |
2137 | */ | |
2138 | if (cachep->ctor && !(cachep->flags & SLAB_POISON)) | |
b28a02de PE |
2139 | cachep->ctor(objp + obj_dbghead(cachep), cachep, |
2140 | ctor_flags); | |
1da177e4 LT |
2141 | |
2142 | if (cachep->flags & SLAB_RED_ZONE) { | |
2143 | if (*dbg_redzone2(cachep, objp) != RED_INACTIVE) | |
2144 | slab_error(cachep, "constructor overwrote the" | |
b28a02de | 2145 | " end of an object"); |
1da177e4 LT |
2146 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE) |
2147 | slab_error(cachep, "constructor overwrote the" | |
b28a02de | 2148 | " start of an object"); |
1da177e4 | 2149 | } |
b28a02de PE |
2150 | if ((cachep->objsize % PAGE_SIZE) == 0 && OFF_SLAB(cachep) |
2151 | && cachep->flags & SLAB_POISON) | |
2152 | kernel_map_pages(virt_to_page(objp), | |
2153 | cachep->objsize / PAGE_SIZE, 0); | |
1da177e4 LT |
2154 | #else |
2155 | if (cachep->ctor) | |
2156 | cachep->ctor(objp, cachep, ctor_flags); | |
2157 | #endif | |
b28a02de | 2158 | slab_bufctl(slabp)[i] = i + 1; |
1da177e4 | 2159 | } |
b28a02de | 2160 | slab_bufctl(slabp)[i - 1] = BUFCTL_END; |
1da177e4 LT |
2161 | slabp->free = 0; |
2162 | } | |
2163 | ||
6daa0e28 | 2164 | static void kmem_flagcheck(kmem_cache_t *cachep, gfp_t flags) |
1da177e4 LT |
2165 | { |
2166 | if (flags & SLAB_DMA) { | |
2167 | if (!(cachep->gfpflags & GFP_DMA)) | |
2168 | BUG(); | |
2169 | } else { | |
2170 | if (cachep->gfpflags & GFP_DMA) | |
2171 | BUG(); | |
2172 | } | |
2173 | } | |
2174 | ||
2175 | static void set_slab_attr(kmem_cache_t *cachep, struct slab *slabp, void *objp) | |
2176 | { | |
2177 | int i; | |
2178 | struct page *page; | |
2179 | ||
2180 | /* Nasty!!!!!! I hope this is OK. */ | |
2181 | i = 1 << cachep->gfporder; | |
2182 | page = virt_to_page(objp); | |
2183 | do { | |
065d41cb PE |
2184 | page_set_cache(page, cachep); |
2185 | page_set_slab(page, slabp); | |
1da177e4 LT |
2186 | page++; |
2187 | } while (--i); | |
2188 | } | |
2189 | ||
2190 | /* | |
2191 | * Grow (by 1) the number of slabs within a cache. This is called by | |
2192 | * kmem_cache_alloc() when there are no active objs left in a cache. | |
2193 | */ | |
dd0fc66f | 2194 | static int cache_grow(kmem_cache_t *cachep, gfp_t flags, int nodeid) |
1da177e4 | 2195 | { |
b28a02de PE |
2196 | struct slab *slabp; |
2197 | void *objp; | |
2198 | size_t offset; | |
2199 | gfp_t local_flags; | |
2200 | unsigned long ctor_flags; | |
e498be7d | 2201 | struct kmem_list3 *l3; |
1da177e4 LT |
2202 | |
2203 | /* Be lazy and only check for valid flags here, | |
b28a02de | 2204 | * keeping it out of the critical path in kmem_cache_alloc(). |
1da177e4 | 2205 | */ |
b28a02de | 2206 | if (flags & ~(SLAB_DMA | SLAB_LEVEL_MASK | SLAB_NO_GROW)) |
1da177e4 LT |
2207 | BUG(); |
2208 | if (flags & SLAB_NO_GROW) | |
2209 | return 0; | |
2210 | ||
2211 | ctor_flags = SLAB_CTOR_CONSTRUCTOR; | |
2212 | local_flags = (flags & SLAB_LEVEL_MASK); | |
2213 | if (!(local_flags & __GFP_WAIT)) | |
2214 | /* | |
2215 | * Not allowed to sleep. Need to tell a constructor about | |
2216 | * this - it might need to know... | |
2217 | */ | |
2218 | ctor_flags |= SLAB_CTOR_ATOMIC; | |
2219 | ||
2220 | /* About to mess with non-constant members - lock. */ | |
2221 | check_irq_off(); | |
2222 | spin_lock(&cachep->spinlock); | |
2223 | ||
2224 | /* Get colour for the slab, and cal the next value. */ | |
2225 | offset = cachep->colour_next; | |
2226 | cachep->colour_next++; | |
2227 | if (cachep->colour_next >= cachep->colour) | |
2228 | cachep->colour_next = 0; | |
2229 | offset *= cachep->colour_off; | |
2230 | ||
2231 | spin_unlock(&cachep->spinlock); | |
2232 | ||
e498be7d | 2233 | check_irq_off(); |
1da177e4 LT |
2234 | if (local_flags & __GFP_WAIT) |
2235 | local_irq_enable(); | |
2236 | ||
2237 | /* | |
2238 | * The test for missing atomic flag is performed here, rather than | |
2239 | * the more obvious place, simply to reduce the critical path length | |
2240 | * in kmem_cache_alloc(). If a caller is seriously mis-behaving they | |
2241 | * will eventually be caught here (where it matters). | |
2242 | */ | |
2243 | kmem_flagcheck(cachep, flags); | |
2244 | ||
e498be7d CL |
2245 | /* Get mem for the objs. |
2246 | * Attempt to allocate a physical page from 'nodeid', | |
2247 | */ | |
1da177e4 LT |
2248 | if (!(objp = kmem_getpages(cachep, flags, nodeid))) |
2249 | goto failed; | |
2250 | ||
2251 | /* Get slab management. */ | |
2252 | if (!(slabp = alloc_slabmgmt(cachep, objp, offset, local_flags))) | |
2253 | goto opps1; | |
2254 | ||
e498be7d | 2255 | slabp->nodeid = nodeid; |
1da177e4 LT |
2256 | set_slab_attr(cachep, slabp, objp); |
2257 | ||
2258 | cache_init_objs(cachep, slabp, ctor_flags); | |
2259 | ||
2260 | if (local_flags & __GFP_WAIT) | |
2261 | local_irq_disable(); | |
2262 | check_irq_off(); | |
e498be7d CL |
2263 | l3 = cachep->nodelists[nodeid]; |
2264 | spin_lock(&l3->list_lock); | |
1da177e4 LT |
2265 | |
2266 | /* Make slab active. */ | |
e498be7d | 2267 | list_add_tail(&slabp->list, &(l3->slabs_free)); |
1da177e4 | 2268 | STATS_INC_GROWN(cachep); |
e498be7d CL |
2269 | l3->free_objects += cachep->num; |
2270 | spin_unlock(&l3->list_lock); | |
1da177e4 | 2271 | return 1; |
b28a02de | 2272 | opps1: |
1da177e4 | 2273 | kmem_freepages(cachep, objp); |
b28a02de | 2274 | failed: |
1da177e4 LT |
2275 | if (local_flags & __GFP_WAIT) |
2276 | local_irq_disable(); | |
2277 | return 0; | |
2278 | } | |
2279 | ||
2280 | #if DEBUG | |
2281 | ||
2282 | /* | |
2283 | * Perform extra freeing checks: | |
2284 | * - detect bad pointers. | |
2285 | * - POISON/RED_ZONE checking | |
2286 | * - destructor calls, for caches with POISON+dtor | |
2287 | */ | |
2288 | static void kfree_debugcheck(const void *objp) | |
2289 | { | |
2290 | struct page *page; | |
2291 | ||
2292 | if (!virt_addr_valid(objp)) { | |
2293 | printk(KERN_ERR "kfree_debugcheck: out of range ptr %lxh.\n", | |
b28a02de PE |
2294 | (unsigned long)objp); |
2295 | BUG(); | |
1da177e4 LT |
2296 | } |
2297 | page = virt_to_page(objp); | |
2298 | if (!PageSlab(page)) { | |
b28a02de PE |
2299 | printk(KERN_ERR "kfree_debugcheck: bad ptr %lxh.\n", |
2300 | (unsigned long)objp); | |
1da177e4 LT |
2301 | BUG(); |
2302 | } | |
2303 | } | |
2304 | ||
2305 | static void *cache_free_debugcheck(kmem_cache_t *cachep, void *objp, | |
b28a02de | 2306 | void *caller) |
1da177e4 LT |
2307 | { |
2308 | struct page *page; | |
2309 | unsigned int objnr; | |
2310 | struct slab *slabp; | |
2311 | ||
2312 | objp -= obj_dbghead(cachep); | |
2313 | kfree_debugcheck(objp); | |
2314 | page = virt_to_page(objp); | |
2315 | ||
065d41cb | 2316 | if (page_get_cache(page) != cachep) { |
b28a02de PE |
2317 | printk(KERN_ERR |
2318 | "mismatch in kmem_cache_free: expected cache %p, got %p\n", | |
2319 | page_get_cache(page), cachep); | |
1da177e4 | 2320 | printk(KERN_ERR "%p is %s.\n", cachep, cachep->name); |
b28a02de PE |
2321 | printk(KERN_ERR "%p is %s.\n", page_get_cache(page), |
2322 | page_get_cache(page)->name); | |
1da177e4 LT |
2323 | WARN_ON(1); |
2324 | } | |
065d41cb | 2325 | slabp = page_get_slab(page); |
1da177e4 LT |
2326 | |
2327 | if (cachep->flags & SLAB_RED_ZONE) { | |
b28a02de PE |
2328 | if (*dbg_redzone1(cachep, objp) != RED_ACTIVE |
2329 | || *dbg_redzone2(cachep, objp) != RED_ACTIVE) { | |
2330 | slab_error(cachep, | |
2331 | "double free, or memory outside" | |
2332 | " object was overwritten"); | |
2333 | printk(KERN_ERR | |
2334 | "%p: redzone 1: 0x%lx, redzone 2: 0x%lx.\n", | |
2335 | objp, *dbg_redzone1(cachep, objp), | |
2336 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
2337 | } |
2338 | *dbg_redzone1(cachep, objp) = RED_INACTIVE; | |
2339 | *dbg_redzone2(cachep, objp) = RED_INACTIVE; | |
2340 | } | |
2341 | if (cachep->flags & SLAB_STORE_USER) | |
2342 | *dbg_userword(cachep, objp) = caller; | |
2343 | ||
b28a02de | 2344 | objnr = (objp - slabp->s_mem) / cachep->objsize; |
1da177e4 LT |
2345 | |
2346 | BUG_ON(objnr >= cachep->num); | |
b28a02de | 2347 | BUG_ON(objp != slabp->s_mem + objnr * cachep->objsize); |
1da177e4 LT |
2348 | |
2349 | if (cachep->flags & SLAB_DEBUG_INITIAL) { | |
2350 | /* Need to call the slab's constructor so the | |
2351 | * caller can perform a verify of its state (debugging). | |
2352 | * Called without the cache-lock held. | |
2353 | */ | |
b28a02de PE |
2354 | cachep->ctor(objp + obj_dbghead(cachep), |
2355 | cachep, SLAB_CTOR_CONSTRUCTOR | SLAB_CTOR_VERIFY); | |
1da177e4 LT |
2356 | } |
2357 | if (cachep->flags & SLAB_POISON && cachep->dtor) { | |
2358 | /* we want to cache poison the object, | |
2359 | * call the destruction callback | |
2360 | */ | |
b28a02de | 2361 | cachep->dtor(objp + obj_dbghead(cachep), cachep, 0); |
1da177e4 LT |
2362 | } |
2363 | if (cachep->flags & SLAB_POISON) { | |
2364 | #ifdef CONFIG_DEBUG_PAGEALLOC | |
2365 | if ((cachep->objsize % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) { | |
2366 | store_stackinfo(cachep, objp, (unsigned long)caller); | |
b28a02de PE |
2367 | kernel_map_pages(virt_to_page(objp), |
2368 | cachep->objsize / PAGE_SIZE, 0); | |
1da177e4 LT |
2369 | } else { |
2370 | poison_obj(cachep, objp, POISON_FREE); | |
2371 | } | |
2372 | #else | |
2373 | poison_obj(cachep, objp, POISON_FREE); | |
2374 | #endif | |
2375 | } | |
2376 | return objp; | |
2377 | } | |
2378 | ||
2379 | static void check_slabp(kmem_cache_t *cachep, struct slab *slabp) | |
2380 | { | |
2381 | kmem_bufctl_t i; | |
2382 | int entries = 0; | |
b28a02de | 2383 | |
1da177e4 LT |
2384 | /* Check slab's freelist to see if this obj is there. */ |
2385 | for (i = slabp->free; i != BUFCTL_END; i = slab_bufctl(slabp)[i]) { | |
2386 | entries++; | |
2387 | if (entries > cachep->num || i >= cachep->num) | |
2388 | goto bad; | |
2389 | } | |
2390 | if (entries != cachep->num - slabp->inuse) { | |
b28a02de PE |
2391 | bad: |
2392 | printk(KERN_ERR | |
2393 | "slab: Internal list corruption detected in cache '%s'(%d), slabp %p(%d). Hexdump:\n", | |
2394 | cachep->name, cachep->num, slabp, slabp->inuse); | |
2395 | for (i = 0; | |
2396 | i < sizeof(slabp) + cachep->num * sizeof(kmem_bufctl_t); | |
2397 | i++) { | |
2398 | if ((i % 16) == 0) | |
1da177e4 | 2399 | printk("\n%03x:", i); |
b28a02de | 2400 | printk(" %02x", ((unsigned char *)slabp)[i]); |
1da177e4 LT |
2401 | } |
2402 | printk("\n"); | |
2403 | BUG(); | |
2404 | } | |
2405 | } | |
2406 | #else | |
2407 | #define kfree_debugcheck(x) do { } while(0) | |
2408 | #define cache_free_debugcheck(x,objp,z) (objp) | |
2409 | #define check_slabp(x,y) do { } while(0) | |
2410 | #endif | |
2411 | ||
dd0fc66f | 2412 | static void *cache_alloc_refill(kmem_cache_t *cachep, gfp_t flags) |
1da177e4 LT |
2413 | { |
2414 | int batchcount; | |
2415 | struct kmem_list3 *l3; | |
2416 | struct array_cache *ac; | |
2417 | ||
2418 | check_irq_off(); | |
2419 | ac = ac_data(cachep); | |
b28a02de | 2420 | retry: |
1da177e4 LT |
2421 | batchcount = ac->batchcount; |
2422 | if (!ac->touched && batchcount > BATCHREFILL_LIMIT) { | |
2423 | /* if there was little recent activity on this | |
2424 | * cache, then perform only a partial refill. | |
2425 | * Otherwise we could generate refill bouncing. | |
2426 | */ | |
2427 | batchcount = BATCHREFILL_LIMIT; | |
2428 | } | |
e498be7d CL |
2429 | l3 = cachep->nodelists[numa_node_id()]; |
2430 | ||
2431 | BUG_ON(ac->avail > 0 || !l3); | |
2432 | spin_lock(&l3->list_lock); | |
1da177e4 | 2433 | |
1da177e4 LT |
2434 | if (l3->shared) { |
2435 | struct array_cache *shared_array = l3->shared; | |
2436 | if (shared_array->avail) { | |
2437 | if (batchcount > shared_array->avail) | |
2438 | batchcount = shared_array->avail; | |
2439 | shared_array->avail -= batchcount; | |
2440 | ac->avail = batchcount; | |
e498be7d | 2441 | memcpy(ac->entry, |
b28a02de PE |
2442 | &(shared_array->entry[shared_array->avail]), |
2443 | sizeof(void *) * batchcount); | |
1da177e4 LT |
2444 | shared_array->touched = 1; |
2445 | goto alloc_done; | |
2446 | } | |
2447 | } | |
2448 | while (batchcount > 0) { | |
2449 | struct list_head *entry; | |
2450 | struct slab *slabp; | |
2451 | /* Get slab alloc is to come from. */ | |
2452 | entry = l3->slabs_partial.next; | |
2453 | if (entry == &l3->slabs_partial) { | |
2454 | l3->free_touched = 1; | |
2455 | entry = l3->slabs_free.next; | |
2456 | if (entry == &l3->slabs_free) | |
2457 | goto must_grow; | |
2458 | } | |
2459 | ||
2460 | slabp = list_entry(entry, struct slab, list); | |
2461 | check_slabp(cachep, slabp); | |
2462 | check_spinlock_acquired(cachep); | |
2463 | while (slabp->inuse < cachep->num && batchcount--) { | |
2464 | kmem_bufctl_t next; | |
2465 | STATS_INC_ALLOCED(cachep); | |
2466 | STATS_INC_ACTIVE(cachep); | |
2467 | STATS_SET_HIGH(cachep); | |
2468 | ||
2469 | /* get obj pointer */ | |
e498be7d | 2470 | ac->entry[ac->avail++] = slabp->s_mem + |
b28a02de | 2471 | slabp->free * cachep->objsize; |
1da177e4 LT |
2472 | |
2473 | slabp->inuse++; | |
2474 | next = slab_bufctl(slabp)[slabp->free]; | |
2475 | #if DEBUG | |
2476 | slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE; | |
09ad4bbc | 2477 | WARN_ON(numa_node_id() != slabp->nodeid); |
1da177e4 | 2478 | #endif |
b28a02de | 2479 | slabp->free = next; |
1da177e4 LT |
2480 | } |
2481 | check_slabp(cachep, slabp); | |
2482 | ||
2483 | /* move slabp to correct slabp list: */ | |
2484 | list_del(&slabp->list); | |
2485 | if (slabp->free == BUFCTL_END) | |
2486 | list_add(&slabp->list, &l3->slabs_full); | |
2487 | else | |
2488 | list_add(&slabp->list, &l3->slabs_partial); | |
2489 | } | |
2490 | ||
b28a02de | 2491 | must_grow: |
1da177e4 | 2492 | l3->free_objects -= ac->avail; |
b28a02de | 2493 | alloc_done: |
e498be7d | 2494 | spin_unlock(&l3->list_lock); |
1da177e4 LT |
2495 | |
2496 | if (unlikely(!ac->avail)) { | |
2497 | int x; | |
e498be7d CL |
2498 | x = cache_grow(cachep, flags, numa_node_id()); |
2499 | ||
1da177e4 LT |
2500 | // cache_grow can reenable interrupts, then ac could change. |
2501 | ac = ac_data(cachep); | |
2502 | if (!x && ac->avail == 0) // no objects in sight? abort | |
2503 | return NULL; | |
2504 | ||
b28a02de | 2505 | if (!ac->avail) // objects refilled by interrupt? |
1da177e4 LT |
2506 | goto retry; |
2507 | } | |
2508 | ac->touched = 1; | |
e498be7d | 2509 | return ac->entry[--ac->avail]; |
1da177e4 LT |
2510 | } |
2511 | ||
2512 | static inline void | |
dd0fc66f | 2513 | cache_alloc_debugcheck_before(kmem_cache_t *cachep, gfp_t flags) |
1da177e4 LT |
2514 | { |
2515 | might_sleep_if(flags & __GFP_WAIT); | |
2516 | #if DEBUG | |
2517 | kmem_flagcheck(cachep, flags); | |
2518 | #endif | |
2519 | } | |
2520 | ||
2521 | #if DEBUG | |
b28a02de PE |
2522 | static void *cache_alloc_debugcheck_after(kmem_cache_t *cachep, gfp_t flags, |
2523 | void *objp, void *caller) | |
1da177e4 | 2524 | { |
b28a02de | 2525 | if (!objp) |
1da177e4 | 2526 | return objp; |
b28a02de | 2527 | if (cachep->flags & SLAB_POISON) { |
1da177e4 LT |
2528 | #ifdef CONFIG_DEBUG_PAGEALLOC |
2529 | if ((cachep->objsize % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) | |
b28a02de PE |
2530 | kernel_map_pages(virt_to_page(objp), |
2531 | cachep->objsize / PAGE_SIZE, 1); | |
1da177e4 LT |
2532 | else |
2533 | check_poison_obj(cachep, objp); | |
2534 | #else | |
2535 | check_poison_obj(cachep, objp); | |
2536 | #endif | |
2537 | poison_obj(cachep, objp, POISON_INUSE); | |
2538 | } | |
2539 | if (cachep->flags & SLAB_STORE_USER) | |
2540 | *dbg_userword(cachep, objp) = caller; | |
2541 | ||
2542 | if (cachep->flags & SLAB_RED_ZONE) { | |
b28a02de PE |
2543 | if (*dbg_redzone1(cachep, objp) != RED_INACTIVE |
2544 | || *dbg_redzone2(cachep, objp) != RED_INACTIVE) { | |
2545 | slab_error(cachep, | |
2546 | "double free, or memory outside" | |
2547 | " object was overwritten"); | |
2548 | printk(KERN_ERR | |
2549 | "%p: redzone 1: 0x%lx, redzone 2: 0x%lx.\n", | |
2550 | objp, *dbg_redzone1(cachep, objp), | |
2551 | *dbg_redzone2(cachep, objp)); | |
1da177e4 LT |
2552 | } |
2553 | *dbg_redzone1(cachep, objp) = RED_ACTIVE; | |
2554 | *dbg_redzone2(cachep, objp) = RED_ACTIVE; | |
2555 | } | |
2556 | objp += obj_dbghead(cachep); | |
2557 | if (cachep->ctor && cachep->flags & SLAB_POISON) { | |
b28a02de | 2558 | unsigned long ctor_flags = SLAB_CTOR_CONSTRUCTOR; |
1da177e4 LT |
2559 | |
2560 | if (!(flags & __GFP_WAIT)) | |
2561 | ctor_flags |= SLAB_CTOR_ATOMIC; | |
2562 | ||
2563 | cachep->ctor(objp, cachep, ctor_flags); | |
b28a02de | 2564 | } |
1da177e4 LT |
2565 | return objp; |
2566 | } | |
2567 | #else | |
2568 | #define cache_alloc_debugcheck_after(a,b,objp,d) (objp) | |
2569 | #endif | |
2570 | ||
dd0fc66f | 2571 | static inline void *____cache_alloc(kmem_cache_t *cachep, gfp_t flags) |
1da177e4 | 2572 | { |
b28a02de | 2573 | void *objp; |
1da177e4 LT |
2574 | struct array_cache *ac; |
2575 | ||
dc85da15 | 2576 | #ifdef CONFIG_NUMA |
86c562a9 | 2577 | if (unlikely(current->mempolicy && !in_interrupt())) { |
dc85da15 CL |
2578 | int nid = slab_node(current->mempolicy); |
2579 | ||
2580 | if (nid != numa_node_id()) | |
2581 | return __cache_alloc_node(cachep, flags, nid); | |
2582 | } | |
2583 | #endif | |
2584 | ||
5c382300 | 2585 | check_irq_off(); |
1da177e4 LT |
2586 | ac = ac_data(cachep); |
2587 | if (likely(ac->avail)) { | |
2588 | STATS_INC_ALLOCHIT(cachep); | |
2589 | ac->touched = 1; | |
e498be7d | 2590 | objp = ac->entry[--ac->avail]; |
1da177e4 LT |
2591 | } else { |
2592 | STATS_INC_ALLOCMISS(cachep); | |
2593 | objp = cache_alloc_refill(cachep, flags); | |
2594 | } | |
5c382300 AK |
2595 | return objp; |
2596 | } | |
2597 | ||
dd0fc66f | 2598 | static inline void *__cache_alloc(kmem_cache_t *cachep, gfp_t flags) |
5c382300 AK |
2599 | { |
2600 | unsigned long save_flags; | |
b28a02de | 2601 | void *objp; |
5c382300 AK |
2602 | |
2603 | cache_alloc_debugcheck_before(cachep, flags); | |
2604 | ||
2605 | local_irq_save(save_flags); | |
2606 | objp = ____cache_alloc(cachep, flags); | |
1da177e4 | 2607 | local_irq_restore(save_flags); |
34342e86 | 2608 | objp = cache_alloc_debugcheck_after(cachep, flags, objp, |
b28a02de | 2609 | __builtin_return_address(0)); |
34342e86 | 2610 | prefetchw(objp); |
1da177e4 LT |
2611 | return objp; |
2612 | } | |
2613 | ||
e498be7d CL |
2614 | #ifdef CONFIG_NUMA |
2615 | /* | |
2616 | * A interface to enable slab creation on nodeid | |
1da177e4 | 2617 | */ |
6daa0e28 | 2618 | static void *__cache_alloc_node(kmem_cache_t *cachep, gfp_t flags, int nodeid) |
e498be7d CL |
2619 | { |
2620 | struct list_head *entry; | |
b28a02de PE |
2621 | struct slab *slabp; |
2622 | struct kmem_list3 *l3; | |
2623 | void *obj; | |
2624 | kmem_bufctl_t next; | |
2625 | int x; | |
2626 | ||
2627 | l3 = cachep->nodelists[nodeid]; | |
2628 | BUG_ON(!l3); | |
2629 | ||
2630 | retry: | |
2631 | spin_lock(&l3->list_lock); | |
2632 | entry = l3->slabs_partial.next; | |
2633 | if (entry == &l3->slabs_partial) { | |
2634 | l3->free_touched = 1; | |
2635 | entry = l3->slabs_free.next; | |
2636 | if (entry == &l3->slabs_free) | |
2637 | goto must_grow; | |
2638 | } | |
2639 | ||
2640 | slabp = list_entry(entry, struct slab, list); | |
2641 | check_spinlock_acquired_node(cachep, nodeid); | |
2642 | check_slabp(cachep, slabp); | |
2643 | ||
2644 | STATS_INC_NODEALLOCS(cachep); | |
2645 | STATS_INC_ACTIVE(cachep); | |
2646 | STATS_SET_HIGH(cachep); | |
2647 | ||
2648 | BUG_ON(slabp->inuse == cachep->num); | |
2649 | ||
2650 | /* get obj pointer */ | |
2651 | obj = slabp->s_mem + slabp->free * cachep->objsize; | |
2652 | slabp->inuse++; | |
2653 | next = slab_bufctl(slabp)[slabp->free]; | |
e498be7d | 2654 | #if DEBUG |
b28a02de | 2655 | slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE; |
e498be7d | 2656 | #endif |
b28a02de PE |
2657 | slabp->free = next; |
2658 | check_slabp(cachep, slabp); | |
2659 | l3->free_objects--; | |
2660 | /* move slabp to correct slabp list: */ | |
2661 | list_del(&slabp->list); | |
2662 | ||
2663 | if (slabp->free == BUFCTL_END) { | |
2664 | list_add(&slabp->list, &l3->slabs_full); | |
2665 | } else { | |
2666 | list_add(&slabp->list, &l3->slabs_partial); | |
2667 | } | |
e498be7d | 2668 | |
b28a02de PE |
2669 | spin_unlock(&l3->list_lock); |
2670 | goto done; | |
e498be7d | 2671 | |
b28a02de PE |
2672 | must_grow: |
2673 | spin_unlock(&l3->list_lock); | |
2674 | x = cache_grow(cachep, flags, nodeid); | |
1da177e4 | 2675 | |
b28a02de PE |
2676 | if (!x) |
2677 | return NULL; | |
e498be7d | 2678 | |
b28a02de PE |
2679 | goto retry; |
2680 | done: | |
2681 | return obj; | |
e498be7d CL |
2682 | } |
2683 | #endif | |
2684 | ||
2685 | /* | |
2686 | * Caller needs to acquire correct kmem_list's list_lock | |
2687 | */ | |
b28a02de PE |
2688 | static void free_block(kmem_cache_t *cachep, void **objpp, int nr_objects, |
2689 | int node) | |
1da177e4 LT |
2690 | { |
2691 | int i; | |
e498be7d | 2692 | struct kmem_list3 *l3; |
1da177e4 LT |
2693 | |
2694 | for (i = 0; i < nr_objects; i++) { | |
2695 | void *objp = objpp[i]; | |
2696 | struct slab *slabp; | |
2697 | unsigned int objnr; | |
2698 | ||
065d41cb | 2699 | slabp = page_get_slab(virt_to_page(objp)); |
ff69416e | 2700 | l3 = cachep->nodelists[node]; |
1da177e4 LT |
2701 | list_del(&slabp->list); |
2702 | objnr = (objp - slabp->s_mem) / cachep->objsize; | |
ff69416e | 2703 | check_spinlock_acquired_node(cachep, node); |
1da177e4 | 2704 | check_slabp(cachep, slabp); |
e498be7d | 2705 | |
1da177e4 | 2706 | #if DEBUG |
09ad4bbc CL |
2707 | /* Verify that the slab belongs to the intended node */ |
2708 | WARN_ON(slabp->nodeid != node); | |
2709 | ||
1da177e4 | 2710 | if (slab_bufctl(slabp)[objnr] != BUFCTL_FREE) { |
e498be7d | 2711 | printk(KERN_ERR "slab: double free detected in cache " |
b28a02de | 2712 | "'%s', objp %p\n", cachep->name, objp); |
1da177e4 LT |
2713 | BUG(); |
2714 | } | |
2715 | #endif | |
2716 | slab_bufctl(slabp)[objnr] = slabp->free; | |
2717 | slabp->free = objnr; | |
2718 | STATS_DEC_ACTIVE(cachep); | |
2719 | slabp->inuse--; | |
e498be7d | 2720 | l3->free_objects++; |
1da177e4 LT |
2721 | check_slabp(cachep, slabp); |
2722 | ||
2723 | /* fixup slab chains */ | |
2724 | if (slabp->inuse == 0) { | |
e498be7d CL |
2725 | if (l3->free_objects > l3->free_limit) { |
2726 | l3->free_objects -= cachep->num; | |
1da177e4 LT |
2727 | slab_destroy(cachep, slabp); |
2728 | } else { | |
e498be7d | 2729 | list_add(&slabp->list, &l3->slabs_free); |
1da177e4 LT |
2730 | } |
2731 | } else { | |
2732 | /* Unconditionally move a slab to the end of the | |
2733 | * partial list on free - maximum time for the | |
2734 | * other objects to be freed, too. | |
2735 | */ | |
e498be7d | 2736 | list_add_tail(&slabp->list, &l3->slabs_partial); |
1da177e4 LT |
2737 | } |
2738 | } | |
2739 | } | |
2740 | ||
2741 | static void cache_flusharray(kmem_cache_t *cachep, struct array_cache *ac) | |
2742 | { | |
2743 | int batchcount; | |
e498be7d | 2744 | struct kmem_list3 *l3; |
ff69416e | 2745 | int node = numa_node_id(); |
1da177e4 LT |
2746 | |
2747 | batchcount = ac->batchcount; | |
2748 | #if DEBUG | |
2749 | BUG_ON(!batchcount || batchcount > ac->avail); | |
2750 | #endif | |
2751 | check_irq_off(); | |
ff69416e | 2752 | l3 = cachep->nodelists[node]; |
e498be7d CL |
2753 | spin_lock(&l3->list_lock); |
2754 | if (l3->shared) { | |
2755 | struct array_cache *shared_array = l3->shared; | |
b28a02de | 2756 | int max = shared_array->limit - shared_array->avail; |
1da177e4 LT |
2757 | if (max) { |
2758 | if (batchcount > max) | |
2759 | batchcount = max; | |
e498be7d | 2760 | memcpy(&(shared_array->entry[shared_array->avail]), |
b28a02de | 2761 | ac->entry, sizeof(void *) * batchcount); |
1da177e4 LT |
2762 | shared_array->avail += batchcount; |
2763 | goto free_done; | |
2764 | } | |
2765 | } | |
2766 | ||
ff69416e | 2767 | free_block(cachep, ac->entry, batchcount, node); |
b28a02de | 2768 | free_done: |
1da177e4 LT |
2769 | #if STATS |
2770 | { | |
2771 | int i = 0; | |
2772 | struct list_head *p; | |
2773 | ||
e498be7d CL |
2774 | p = l3->slabs_free.next; |
2775 | while (p != &(l3->slabs_free)) { | |
1da177e4 LT |
2776 | struct slab *slabp; |
2777 | ||
2778 | slabp = list_entry(p, struct slab, list); | |
2779 | BUG_ON(slabp->inuse); | |
2780 | ||
2781 | i++; | |
2782 | p = p->next; | |
2783 | } | |
2784 | STATS_SET_FREEABLE(cachep, i); | |
2785 | } | |
2786 | #endif | |
e498be7d | 2787 | spin_unlock(&l3->list_lock); |
1da177e4 | 2788 | ac->avail -= batchcount; |
e498be7d | 2789 | memmove(ac->entry, &(ac->entry[batchcount]), |
b28a02de | 2790 | sizeof(void *) * ac->avail); |
1da177e4 LT |
2791 | } |
2792 | ||
2793 | /* | |
2794 | * __cache_free | |
2795 | * Release an obj back to its cache. If the obj has a constructed | |
2796 | * state, it must be in this state _before_ it is released. | |
2797 | * | |
2798 | * Called with disabled ints. | |
2799 | */ | |
2800 | static inline void __cache_free(kmem_cache_t *cachep, void *objp) | |
2801 | { | |
2802 | struct array_cache *ac = ac_data(cachep); | |
2803 | ||
2804 | check_irq_off(); | |
2805 | objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0)); | |
2806 | ||
e498be7d CL |
2807 | /* Make sure we are not freeing a object from another |
2808 | * node to the array cache on this cpu. | |
2809 | */ | |
2810 | #ifdef CONFIG_NUMA | |
2811 | { | |
2812 | struct slab *slabp; | |
065d41cb | 2813 | slabp = page_get_slab(virt_to_page(objp)); |
e498be7d CL |
2814 | if (unlikely(slabp->nodeid != numa_node_id())) { |
2815 | struct array_cache *alien = NULL; | |
2816 | int nodeid = slabp->nodeid; | |
b28a02de PE |
2817 | struct kmem_list3 *l3 = |
2818 | cachep->nodelists[numa_node_id()]; | |
e498be7d CL |
2819 | |
2820 | STATS_INC_NODEFREES(cachep); | |
2821 | if (l3->alien && l3->alien[nodeid]) { | |
2822 | alien = l3->alien[nodeid]; | |
2823 | spin_lock(&alien->lock); | |
2824 | if (unlikely(alien->avail == alien->limit)) | |
2825 | __drain_alien_cache(cachep, | |
b28a02de | 2826 | alien, nodeid); |
e498be7d CL |
2827 | alien->entry[alien->avail++] = objp; |
2828 | spin_unlock(&alien->lock); | |
2829 | } else { | |
2830 | spin_lock(&(cachep->nodelists[nodeid])-> | |
b28a02de | 2831 | list_lock); |
ff69416e | 2832 | free_block(cachep, &objp, 1, nodeid); |
e498be7d | 2833 | spin_unlock(&(cachep->nodelists[nodeid])-> |
b28a02de | 2834 | list_lock); |
e498be7d CL |
2835 | } |
2836 | return; | |
2837 | } | |
2838 | } | |
2839 | #endif | |
1da177e4 LT |
2840 | if (likely(ac->avail < ac->limit)) { |
2841 | STATS_INC_FREEHIT(cachep); | |
e498be7d | 2842 | ac->entry[ac->avail++] = objp; |
1da177e4 LT |
2843 | return; |
2844 | } else { | |
2845 | STATS_INC_FREEMISS(cachep); | |
2846 | cache_flusharray(cachep, ac); | |
e498be7d | 2847 | ac->entry[ac->avail++] = objp; |
1da177e4 LT |
2848 | } |
2849 | } | |
2850 | ||
2851 | /** | |
2852 | * kmem_cache_alloc - Allocate an object | |
2853 | * @cachep: The cache to allocate from. | |
2854 | * @flags: See kmalloc(). | |
2855 | * | |
2856 | * Allocate an object from this cache. The flags are only relevant | |
2857 | * if the cache has no available objects. | |
2858 | */ | |
dd0fc66f | 2859 | void *kmem_cache_alloc(kmem_cache_t *cachep, gfp_t flags) |
1da177e4 LT |
2860 | { |
2861 | return __cache_alloc(cachep, flags); | |
2862 | } | |
2863 | EXPORT_SYMBOL(kmem_cache_alloc); | |
2864 | ||
2865 | /** | |
2866 | * kmem_ptr_validate - check if an untrusted pointer might | |
2867 | * be a slab entry. | |
2868 | * @cachep: the cache we're checking against | |
2869 | * @ptr: pointer to validate | |
2870 | * | |
2871 | * This verifies that the untrusted pointer looks sane: | |
2872 | * it is _not_ a guarantee that the pointer is actually | |
2873 | * part of the slab cache in question, but it at least | |
2874 | * validates that the pointer can be dereferenced and | |
2875 | * looks half-way sane. | |
2876 | * | |
2877 | * Currently only used for dentry validation. | |
2878 | */ | |
2879 | int fastcall kmem_ptr_validate(kmem_cache_t *cachep, void *ptr) | |
2880 | { | |
b28a02de | 2881 | unsigned long addr = (unsigned long)ptr; |
1da177e4 | 2882 | unsigned long min_addr = PAGE_OFFSET; |
b28a02de | 2883 | unsigned long align_mask = BYTES_PER_WORD - 1; |
1da177e4 LT |
2884 | unsigned long size = cachep->objsize; |
2885 | struct page *page; | |
2886 | ||
2887 | if (unlikely(addr < min_addr)) | |
2888 | goto out; | |
2889 | if (unlikely(addr > (unsigned long)high_memory - size)) | |
2890 | goto out; | |
2891 | if (unlikely(addr & align_mask)) | |
2892 | goto out; | |
2893 | if (unlikely(!kern_addr_valid(addr))) | |
2894 | goto out; | |
2895 | if (unlikely(!kern_addr_valid(addr + size - 1))) | |
2896 | goto out; | |
2897 | page = virt_to_page(ptr); | |
2898 | if (unlikely(!PageSlab(page))) | |
2899 | goto out; | |
065d41cb | 2900 | if (unlikely(page_get_cache(page) != cachep)) |
1da177e4 LT |
2901 | goto out; |
2902 | return 1; | |
b28a02de | 2903 | out: |
1da177e4 LT |
2904 | return 0; |
2905 | } | |
2906 | ||
2907 | #ifdef CONFIG_NUMA | |
2908 | /** | |
2909 | * kmem_cache_alloc_node - Allocate an object on the specified node | |
2910 | * @cachep: The cache to allocate from. | |
2911 | * @flags: See kmalloc(). | |
2912 | * @nodeid: node number of the target node. | |
2913 | * | |
2914 | * Identical to kmem_cache_alloc, except that this function is slow | |
2915 | * and can sleep. And it will allocate memory on the given node, which | |
2916 | * can improve the performance for cpu bound structures. | |
e498be7d CL |
2917 | * New and improved: it will now make sure that the object gets |
2918 | * put on the correct node list so that there is no false sharing. | |
1da177e4 | 2919 | */ |
dd0fc66f | 2920 | void *kmem_cache_alloc_node(kmem_cache_t *cachep, gfp_t flags, int nodeid) |
1da177e4 | 2921 | { |
e498be7d CL |
2922 | unsigned long save_flags; |
2923 | void *ptr; | |
1da177e4 | 2924 | |
ff69416e | 2925 | if (nodeid == -1) |
e498be7d | 2926 | return __cache_alloc(cachep, flags); |
1da177e4 | 2927 | |
e498be7d CL |
2928 | if (unlikely(!cachep->nodelists[nodeid])) { |
2929 | /* Fall back to __cache_alloc if we run into trouble */ | |
b28a02de PE |
2930 | printk(KERN_WARNING |
2931 | "slab: not allocating in inactive node %d for cache %s\n", | |
2932 | nodeid, cachep->name); | |
2933 | return __cache_alloc(cachep, flags); | |
1da177e4 | 2934 | } |
1da177e4 | 2935 | |
e498be7d CL |
2936 | cache_alloc_debugcheck_before(cachep, flags); |
2937 | local_irq_save(save_flags); | |
5c382300 AK |
2938 | if (nodeid == numa_node_id()) |
2939 | ptr = ____cache_alloc(cachep, flags); | |
2940 | else | |
2941 | ptr = __cache_alloc_node(cachep, flags, nodeid); | |
e498be7d | 2942 | local_irq_restore(save_flags); |
b28a02de PE |
2943 | ptr = |
2944 | cache_alloc_debugcheck_after(cachep, flags, ptr, | |
2945 | __builtin_return_address(0)); | |
1da177e4 | 2946 | |
e498be7d | 2947 | return ptr; |
1da177e4 LT |
2948 | } |
2949 | EXPORT_SYMBOL(kmem_cache_alloc_node); | |
2950 | ||
dd0fc66f | 2951 | void *kmalloc_node(size_t size, gfp_t flags, int node) |
97e2bde4 MS |
2952 | { |
2953 | kmem_cache_t *cachep; | |
2954 | ||
2955 | cachep = kmem_find_general_cachep(size, flags); | |
2956 | if (unlikely(cachep == NULL)) | |
2957 | return NULL; | |
2958 | return kmem_cache_alloc_node(cachep, flags, node); | |
2959 | } | |
2960 | EXPORT_SYMBOL(kmalloc_node); | |
1da177e4 LT |
2961 | #endif |
2962 | ||
2963 | /** | |
2964 | * kmalloc - allocate memory | |
2965 | * @size: how many bytes of memory are required. | |
2966 | * @flags: the type of memory to allocate. | |
2967 | * | |
2968 | * kmalloc is the normal method of allocating memory | |
2969 | * in the kernel. | |
2970 | * | |
2971 | * The @flags argument may be one of: | |
2972 | * | |
2973 | * %GFP_USER - Allocate memory on behalf of user. May sleep. | |
2974 | * | |
2975 | * %GFP_KERNEL - Allocate normal kernel ram. May sleep. | |
2976 | * | |
2977 | * %GFP_ATOMIC - Allocation will not sleep. Use inside interrupt handlers. | |
2978 | * | |
2979 | * Additionally, the %GFP_DMA flag may be set to indicate the memory | |
2980 | * must be suitable for DMA. This can mean different things on different | |
2981 | * platforms. For example, on i386, it means that the memory must come | |
2982 | * from the first 16MB. | |
2983 | */ | |
dd0fc66f | 2984 | void *__kmalloc(size_t size, gfp_t flags) |
1da177e4 LT |
2985 | { |
2986 | kmem_cache_t *cachep; | |
2987 | ||
97e2bde4 MS |
2988 | /* If you want to save a few bytes .text space: replace |
2989 | * __ with kmem_. | |
2990 | * Then kmalloc uses the uninlined functions instead of the inline | |
2991 | * functions. | |
2992 | */ | |
2993 | cachep = __find_general_cachep(size, flags); | |
dbdb9045 AM |
2994 | if (unlikely(cachep == NULL)) |
2995 | return NULL; | |
1da177e4 LT |
2996 | return __cache_alloc(cachep, flags); |
2997 | } | |
2998 | EXPORT_SYMBOL(__kmalloc); | |
2999 | ||
3000 | #ifdef CONFIG_SMP | |
3001 | /** | |
3002 | * __alloc_percpu - allocate one copy of the object for every present | |
3003 | * cpu in the system, zeroing them. | |
3004 | * Objects should be dereferenced using the per_cpu_ptr macro only. | |
3005 | * | |
3006 | * @size: how many bytes of memory are required. | |
1da177e4 | 3007 | */ |
f9f75005 | 3008 | void *__alloc_percpu(size_t size) |
1da177e4 LT |
3009 | { |
3010 | int i; | |
b28a02de | 3011 | struct percpu_data *pdata = kmalloc(sizeof(*pdata), GFP_KERNEL); |
1da177e4 LT |
3012 | |
3013 | if (!pdata) | |
3014 | return NULL; | |
3015 | ||
e498be7d CL |
3016 | /* |
3017 | * Cannot use for_each_online_cpu since a cpu may come online | |
3018 | * and we have no way of figuring out how to fix the array | |
3019 | * that we have allocated then.... | |
3020 | */ | |
3021 | for_each_cpu(i) { | |
3022 | int node = cpu_to_node(i); | |
3023 | ||
3024 | if (node_online(node)) | |
3025 | pdata->ptrs[i] = kmalloc_node(size, GFP_KERNEL, node); | |
3026 | else | |
3027 | pdata->ptrs[i] = kmalloc(size, GFP_KERNEL); | |
1da177e4 LT |
3028 | |
3029 | if (!pdata->ptrs[i]) | |
3030 | goto unwind_oom; | |
3031 | memset(pdata->ptrs[i], 0, size); | |
3032 | } | |
3033 | ||
3034 | /* Catch derefs w/o wrappers */ | |
b28a02de | 3035 | return (void *)(~(unsigned long)pdata); |
1da177e4 | 3036 | |
b28a02de | 3037 | unwind_oom: |
1da177e4 LT |
3038 | while (--i >= 0) { |
3039 | if (!cpu_possible(i)) | |
3040 | continue; | |
3041 | kfree(pdata->ptrs[i]); | |
3042 | } | |
3043 | kfree(pdata); | |
3044 | return NULL; | |
3045 | } | |
3046 | EXPORT_SYMBOL(__alloc_percpu); | |
3047 | #endif | |
3048 | ||
3049 | /** | |
3050 | * kmem_cache_free - Deallocate an object | |
3051 | * @cachep: The cache the allocation was from. | |
3052 | * @objp: The previously allocated object. | |
3053 | * | |
3054 | * Free an object which was previously allocated from this | |
3055 | * cache. | |
3056 | */ | |
3057 | void kmem_cache_free(kmem_cache_t *cachep, void *objp) | |
3058 | { | |
3059 | unsigned long flags; | |
3060 | ||
3061 | local_irq_save(flags); | |
3062 | __cache_free(cachep, objp); | |
3063 | local_irq_restore(flags); | |
3064 | } | |
3065 | EXPORT_SYMBOL(kmem_cache_free); | |
3066 | ||
1da177e4 LT |
3067 | /** |
3068 | * kfree - free previously allocated memory | |
3069 | * @objp: pointer returned by kmalloc. | |
3070 | * | |
80e93eff PE |
3071 | * If @objp is NULL, no operation is performed. |
3072 | * | |
1da177e4 LT |
3073 | * Don't free memory not originally allocated by kmalloc() |
3074 | * or you will run into trouble. | |
3075 | */ | |
3076 | void kfree(const void *objp) | |
3077 | { | |
3078 | kmem_cache_t *c; | |
3079 | unsigned long flags; | |
3080 | ||
3081 | if (unlikely(!objp)) | |
3082 | return; | |
3083 | local_irq_save(flags); | |
3084 | kfree_debugcheck(objp); | |
065d41cb | 3085 | c = page_get_cache(virt_to_page(objp)); |
a4fc7ab1 | 3086 | mutex_debug_check_no_locks_freed(objp, obj_reallen(c)); |
b28a02de | 3087 | __cache_free(c, (void *)objp); |
1da177e4 LT |
3088 | local_irq_restore(flags); |
3089 | } | |
3090 | EXPORT_SYMBOL(kfree); | |
3091 | ||
3092 | #ifdef CONFIG_SMP | |
3093 | /** | |
3094 | * free_percpu - free previously allocated percpu memory | |
3095 | * @objp: pointer returned by alloc_percpu. | |
3096 | * | |
3097 | * Don't free memory not originally allocated by alloc_percpu() | |
3098 | * The complemented objp is to check for that. | |
3099 | */ | |
b28a02de | 3100 | void free_percpu(const void *objp) |
1da177e4 LT |
3101 | { |
3102 | int i; | |
b28a02de | 3103 | struct percpu_data *p = (struct percpu_data *)(~(unsigned long)objp); |
1da177e4 | 3104 | |
e498be7d CL |
3105 | /* |
3106 | * We allocate for all cpus so we cannot use for online cpu here. | |
3107 | */ | |
3108 | for_each_cpu(i) | |
b28a02de | 3109 | kfree(p->ptrs[i]); |
1da177e4 LT |
3110 | kfree(p); |
3111 | } | |
3112 | EXPORT_SYMBOL(free_percpu); | |
3113 | #endif | |
3114 | ||
3115 | unsigned int kmem_cache_size(kmem_cache_t *cachep) | |
3116 | { | |
3117 | return obj_reallen(cachep); | |
3118 | } | |
3119 | EXPORT_SYMBOL(kmem_cache_size); | |
3120 | ||
1944972d ACM |
3121 | const char *kmem_cache_name(kmem_cache_t *cachep) |
3122 | { | |
3123 | return cachep->name; | |
3124 | } | |
3125 | EXPORT_SYMBOL_GPL(kmem_cache_name); | |
3126 | ||
e498be7d CL |
3127 | /* |
3128 | * This initializes kmem_list3 for all nodes. | |
3129 | */ | |
3130 | static int alloc_kmemlist(kmem_cache_t *cachep) | |
3131 | { | |
3132 | int node; | |
3133 | struct kmem_list3 *l3; | |
3134 | int err = 0; | |
3135 | ||
3136 | for_each_online_node(node) { | |
3137 | struct array_cache *nc = NULL, *new; | |
3138 | struct array_cache **new_alien = NULL; | |
3139 | #ifdef CONFIG_NUMA | |
3140 | if (!(new_alien = alloc_alien_cache(node, cachep->limit))) | |
3141 | goto fail; | |
3142 | #endif | |
b28a02de PE |
3143 | if (!(new = alloc_arraycache(node, (cachep->shared * |
3144 | cachep->batchcount), | |
3145 | 0xbaadf00d))) | |
e498be7d CL |
3146 | goto fail; |
3147 | if ((l3 = cachep->nodelists[node])) { | |
3148 | ||
3149 | spin_lock_irq(&l3->list_lock); | |
3150 | ||
3151 | if ((nc = cachep->nodelists[node]->shared)) | |
b28a02de | 3152 | free_block(cachep, nc->entry, nc->avail, node); |
e498be7d CL |
3153 | |
3154 | l3->shared = new; | |
3155 | if (!cachep->nodelists[node]->alien) { | |
3156 | l3->alien = new_alien; | |
3157 | new_alien = NULL; | |
3158 | } | |
b28a02de PE |
3159 | l3->free_limit = (1 + nr_cpus_node(node)) * |
3160 | cachep->batchcount + cachep->num; | |
e498be7d CL |
3161 | spin_unlock_irq(&l3->list_lock); |
3162 | kfree(nc); | |
3163 | free_alien_cache(new_alien); | |
3164 | continue; | |
3165 | } | |
3166 | if (!(l3 = kmalloc_node(sizeof(struct kmem_list3), | |
b28a02de | 3167 | GFP_KERNEL, node))) |
e498be7d CL |
3168 | goto fail; |
3169 | ||
3170 | kmem_list3_init(l3); | |
3171 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3 + | |
b28a02de | 3172 | ((unsigned long)cachep) % REAPTIMEOUT_LIST3; |
e498be7d CL |
3173 | l3->shared = new; |
3174 | l3->alien = new_alien; | |
b28a02de PE |
3175 | l3->free_limit = (1 + nr_cpus_node(node)) * |
3176 | cachep->batchcount + cachep->num; | |
e498be7d CL |
3177 | cachep->nodelists[node] = l3; |
3178 | } | |
3179 | return err; | |
b28a02de | 3180 | fail: |
e498be7d CL |
3181 | err = -ENOMEM; |
3182 | return err; | |
3183 | } | |
3184 | ||
1da177e4 LT |
3185 | struct ccupdate_struct { |
3186 | kmem_cache_t *cachep; | |
3187 | struct array_cache *new[NR_CPUS]; | |
3188 | }; | |
3189 | ||
3190 | static void do_ccupdate_local(void *info) | |
3191 | { | |
3192 | struct ccupdate_struct *new = (struct ccupdate_struct *)info; | |
3193 | struct array_cache *old; | |
3194 | ||
3195 | check_irq_off(); | |
3196 | old = ac_data(new->cachep); | |
e498be7d | 3197 | |
1da177e4 LT |
3198 | new->cachep->array[smp_processor_id()] = new->new[smp_processor_id()]; |
3199 | new->new[smp_processor_id()] = old; | |
3200 | } | |
3201 | ||
1da177e4 | 3202 | static int do_tune_cpucache(kmem_cache_t *cachep, int limit, int batchcount, |
b28a02de | 3203 | int shared) |
1da177e4 LT |
3204 | { |
3205 | struct ccupdate_struct new; | |
e498be7d | 3206 | int i, err; |
1da177e4 | 3207 | |
b28a02de | 3208 | memset(&new.new, 0, sizeof(new.new)); |
e498be7d | 3209 | for_each_online_cpu(i) { |
b28a02de PE |
3210 | new.new[i] = |
3211 | alloc_arraycache(cpu_to_node(i), limit, batchcount); | |
e498be7d | 3212 | if (!new.new[i]) { |
b28a02de PE |
3213 | for (i--; i >= 0; i--) |
3214 | kfree(new.new[i]); | |
e498be7d | 3215 | return -ENOMEM; |
1da177e4 LT |
3216 | } |
3217 | } | |
3218 | new.cachep = cachep; | |
3219 | ||
3220 | smp_call_function_all_cpus(do_ccupdate_local, (void *)&new); | |
e498be7d | 3221 | |
1da177e4 LT |
3222 | check_irq_on(); |
3223 | spin_lock_irq(&cachep->spinlock); | |
3224 | cachep->batchcount = batchcount; | |
3225 | cachep->limit = limit; | |
e498be7d | 3226 | cachep->shared = shared; |
1da177e4 LT |
3227 | spin_unlock_irq(&cachep->spinlock); |
3228 | ||
e498be7d | 3229 | for_each_online_cpu(i) { |
1da177e4 LT |
3230 | struct array_cache *ccold = new.new[i]; |
3231 | if (!ccold) | |
3232 | continue; | |
e498be7d | 3233 | spin_lock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
ff69416e | 3234 | free_block(cachep, ccold->entry, ccold->avail, cpu_to_node(i)); |
e498be7d | 3235 | spin_unlock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock); |
1da177e4 LT |
3236 | kfree(ccold); |
3237 | } | |
1da177e4 | 3238 | |
e498be7d CL |
3239 | err = alloc_kmemlist(cachep); |
3240 | if (err) { | |
3241 | printk(KERN_ERR "alloc_kmemlist failed for %s, error %d.\n", | |
b28a02de | 3242 | cachep->name, -err); |
e498be7d | 3243 | BUG(); |
1da177e4 | 3244 | } |
1da177e4 LT |
3245 | return 0; |
3246 | } | |
3247 | ||
1da177e4 LT |
3248 | static void enable_cpucache(kmem_cache_t *cachep) |
3249 | { | |
3250 | int err; | |
3251 | int limit, shared; | |
3252 | ||
3253 | /* The head array serves three purposes: | |
3254 | * - create a LIFO ordering, i.e. return objects that are cache-warm | |
3255 | * - reduce the number of spinlock operations. | |
3256 | * - reduce the number of linked list operations on the slab and | |
3257 | * bufctl chains: array operations are cheaper. | |
3258 | * The numbers are guessed, we should auto-tune as described by | |
3259 | * Bonwick. | |
3260 | */ | |
3261 | if (cachep->objsize > 131072) | |
3262 | limit = 1; | |
3263 | else if (cachep->objsize > PAGE_SIZE) | |
3264 | limit = 8; | |
3265 | else if (cachep->objsize > 1024) | |
3266 | limit = 24; | |
3267 | else if (cachep->objsize > 256) | |
3268 | limit = 54; | |
3269 | else | |
3270 | limit = 120; | |
3271 | ||
3272 | /* Cpu bound tasks (e.g. network routing) can exhibit cpu bound | |
3273 | * allocation behaviour: Most allocs on one cpu, most free operations | |
3274 | * on another cpu. For these cases, an efficient object passing between | |
3275 | * cpus is necessary. This is provided by a shared array. The array | |
3276 | * replaces Bonwick's magazine layer. | |
3277 | * On uniprocessor, it's functionally equivalent (but less efficient) | |
3278 | * to a larger limit. Thus disabled by default. | |
3279 | */ | |
3280 | shared = 0; | |
3281 | #ifdef CONFIG_SMP | |
3282 | if (cachep->objsize <= PAGE_SIZE) | |
3283 | shared = 8; | |
3284 | #endif | |
3285 | ||
3286 | #if DEBUG | |
3287 | /* With debugging enabled, large batchcount lead to excessively | |
3288 | * long periods with disabled local interrupts. Limit the | |
3289 | * batchcount | |
3290 | */ | |
3291 | if (limit > 32) | |
3292 | limit = 32; | |
3293 | #endif | |
b28a02de | 3294 | err = do_tune_cpucache(cachep, limit, (limit + 1) / 2, shared); |
1da177e4 LT |
3295 | if (err) |
3296 | printk(KERN_ERR "enable_cpucache failed for %s, error %d.\n", | |
b28a02de | 3297 | cachep->name, -err); |
1da177e4 LT |
3298 | } |
3299 | ||
b28a02de PE |
3300 | static void drain_array_locked(kmem_cache_t *cachep, struct array_cache *ac, |
3301 | int force, int node) | |
1da177e4 LT |
3302 | { |
3303 | int tofree; | |
3304 | ||
e498be7d | 3305 | check_spinlock_acquired_node(cachep, node); |
1da177e4 LT |
3306 | if (ac->touched && !force) { |
3307 | ac->touched = 0; | |
3308 | } else if (ac->avail) { | |
b28a02de | 3309 | tofree = force ? ac->avail : (ac->limit + 4) / 5; |
1da177e4 | 3310 | if (tofree > ac->avail) { |
b28a02de | 3311 | tofree = (ac->avail + 1) / 2; |
1da177e4 | 3312 | } |
ff69416e | 3313 | free_block(cachep, ac->entry, tofree, node); |
1da177e4 | 3314 | ac->avail -= tofree; |
e498be7d | 3315 | memmove(ac->entry, &(ac->entry[tofree]), |
b28a02de | 3316 | sizeof(void *) * ac->avail); |
1da177e4 LT |
3317 | } |
3318 | } | |
3319 | ||
3320 | /** | |
3321 | * cache_reap - Reclaim memory from caches. | |
1e5d5331 | 3322 | * @unused: unused parameter |
1da177e4 LT |
3323 | * |
3324 | * Called from workqueue/eventd every few seconds. | |
3325 | * Purpose: | |
3326 | * - clear the per-cpu caches for this CPU. | |
3327 | * - return freeable pages to the main free memory pool. | |
3328 | * | |
fc0abb14 | 3329 | * If we cannot acquire the cache chain mutex then just give up - we'll |
1da177e4 LT |
3330 | * try again on the next iteration. |
3331 | */ | |
3332 | static void cache_reap(void *unused) | |
3333 | { | |
3334 | struct list_head *walk; | |
e498be7d | 3335 | struct kmem_list3 *l3; |
1da177e4 | 3336 | |
fc0abb14 | 3337 | if (!mutex_trylock(&cache_chain_mutex)) { |
1da177e4 | 3338 | /* Give up. Setup the next iteration. */ |
b28a02de PE |
3339 | schedule_delayed_work(&__get_cpu_var(reap_work), |
3340 | REAPTIMEOUT_CPUC); | |
1da177e4 LT |
3341 | return; |
3342 | } | |
3343 | ||
3344 | list_for_each(walk, &cache_chain) { | |
3345 | kmem_cache_t *searchp; | |
b28a02de | 3346 | struct list_head *p; |
1da177e4 LT |
3347 | int tofree; |
3348 | struct slab *slabp; | |
3349 | ||
3350 | searchp = list_entry(walk, kmem_cache_t, next); | |
3351 | ||
3352 | if (searchp->flags & SLAB_NO_REAP) | |
3353 | goto next; | |
3354 | ||
3355 | check_irq_on(); | |
3356 | ||
e498be7d CL |
3357 | l3 = searchp->nodelists[numa_node_id()]; |
3358 | if (l3->alien) | |
3359 | drain_alien_cache(searchp, l3); | |
3360 | spin_lock_irq(&l3->list_lock); | |
1da177e4 | 3361 | |
e498be7d | 3362 | drain_array_locked(searchp, ac_data(searchp), 0, |
b28a02de | 3363 | numa_node_id()); |
1da177e4 | 3364 | |
e498be7d | 3365 | if (time_after(l3->next_reap, jiffies)) |
1da177e4 LT |
3366 | goto next_unlock; |
3367 | ||
e498be7d | 3368 | l3->next_reap = jiffies + REAPTIMEOUT_LIST3; |
1da177e4 | 3369 | |
e498be7d CL |
3370 | if (l3->shared) |
3371 | drain_array_locked(searchp, l3->shared, 0, | |
b28a02de | 3372 | numa_node_id()); |
1da177e4 | 3373 | |
e498be7d CL |
3374 | if (l3->free_touched) { |
3375 | l3->free_touched = 0; | |
1da177e4 LT |
3376 | goto next_unlock; |
3377 | } | |
3378 | ||
b28a02de PE |
3379 | tofree = |
3380 | (l3->free_limit + 5 * searchp->num - | |
3381 | 1) / (5 * searchp->num); | |
1da177e4 | 3382 | do { |
e498be7d CL |
3383 | p = l3->slabs_free.next; |
3384 | if (p == &(l3->slabs_free)) | |
1da177e4 LT |
3385 | break; |
3386 | ||
3387 | slabp = list_entry(p, struct slab, list); | |
3388 | BUG_ON(slabp->inuse); | |
3389 | list_del(&slabp->list); | |
3390 | STATS_INC_REAPED(searchp); | |
3391 | ||
3392 | /* Safe to drop the lock. The slab is no longer | |
3393 | * linked to the cache. | |
3394 | * searchp cannot disappear, we hold | |
3395 | * cache_chain_lock | |
3396 | */ | |
e498be7d CL |
3397 | l3->free_objects -= searchp->num; |
3398 | spin_unlock_irq(&l3->list_lock); | |
1da177e4 | 3399 | slab_destroy(searchp, slabp); |
e498be7d | 3400 | spin_lock_irq(&l3->list_lock); |
b28a02de PE |
3401 | } while (--tofree > 0); |
3402 | next_unlock: | |
e498be7d | 3403 | spin_unlock_irq(&l3->list_lock); |
b28a02de | 3404 | next: |
1da177e4 LT |
3405 | cond_resched(); |
3406 | } | |
3407 | check_irq_on(); | |
fc0abb14 | 3408 | mutex_unlock(&cache_chain_mutex); |
4ae7c039 | 3409 | drain_remote_pages(); |
1da177e4 | 3410 | /* Setup the next iteration */ |
cd61ef62 | 3411 | schedule_delayed_work(&__get_cpu_var(reap_work), REAPTIMEOUT_CPUC); |
1da177e4 LT |
3412 | } |
3413 | ||
3414 | #ifdef CONFIG_PROC_FS | |
3415 | ||
85289f98 | 3416 | static void print_slabinfo_header(struct seq_file *m) |
1da177e4 | 3417 | { |
85289f98 PE |
3418 | /* |
3419 | * Output format version, so at least we can change it | |
3420 | * without _too_ many complaints. | |
3421 | */ | |
1da177e4 | 3422 | #if STATS |
85289f98 | 3423 | seq_puts(m, "slabinfo - version: 2.1 (statistics)\n"); |
1da177e4 | 3424 | #else |
85289f98 | 3425 | seq_puts(m, "slabinfo - version: 2.1\n"); |
1da177e4 | 3426 | #endif |
85289f98 PE |
3427 | seq_puts(m, "# name <active_objs> <num_objs> <objsize> " |
3428 | "<objperslab> <pagesperslab>"); | |
3429 | seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>"); | |
3430 | seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>"); | |
1da177e4 | 3431 | #if STATS |
85289f98 PE |
3432 | seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> " |
3433 | "<error> <maxfreeable> <nodeallocs> <remotefrees>"); | |
3434 | seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>"); | |
1da177e4 | 3435 | #endif |
85289f98 PE |
3436 | seq_putc(m, '\n'); |
3437 | } | |
3438 | ||
3439 | static void *s_start(struct seq_file *m, loff_t *pos) | |
3440 | { | |
3441 | loff_t n = *pos; | |
3442 | struct list_head *p; | |
3443 | ||
fc0abb14 | 3444 | mutex_lock(&cache_chain_mutex); |
85289f98 PE |
3445 | if (!n) |
3446 | print_slabinfo_header(m); | |
1da177e4 LT |
3447 | p = cache_chain.next; |
3448 | while (n--) { | |
3449 | p = p->next; | |
3450 | if (p == &cache_chain) | |
3451 | return NULL; | |
3452 | } | |
3453 | return list_entry(p, kmem_cache_t, next); | |
3454 | } | |
3455 | ||
3456 | static void *s_next(struct seq_file *m, void *p, loff_t *pos) | |
3457 | { | |
3458 | kmem_cache_t *cachep = p; | |
3459 | ++*pos; | |
3460 | return cachep->next.next == &cache_chain ? NULL | |
b28a02de | 3461 | : list_entry(cachep->next.next, kmem_cache_t, next); |
1da177e4 LT |
3462 | } |
3463 | ||
3464 | static void s_stop(struct seq_file *m, void *p) | |
3465 | { | |
fc0abb14 | 3466 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
3467 | } |
3468 | ||
3469 | static int s_show(struct seq_file *m, void *p) | |
3470 | { | |
3471 | kmem_cache_t *cachep = p; | |
3472 | struct list_head *q; | |
b28a02de PE |
3473 | struct slab *slabp; |
3474 | unsigned long active_objs; | |
3475 | unsigned long num_objs; | |
3476 | unsigned long active_slabs = 0; | |
3477 | unsigned long num_slabs, free_objects = 0, shared_avail = 0; | |
e498be7d | 3478 | const char *name; |
1da177e4 | 3479 | char *error = NULL; |
e498be7d CL |
3480 | int node; |
3481 | struct kmem_list3 *l3; | |
1da177e4 LT |
3482 | |
3483 | check_irq_on(); | |
3484 | spin_lock_irq(&cachep->spinlock); | |
3485 | active_objs = 0; | |
3486 | num_slabs = 0; | |
e498be7d CL |
3487 | for_each_online_node(node) { |
3488 | l3 = cachep->nodelists[node]; | |
3489 | if (!l3) | |
3490 | continue; | |
3491 | ||
3492 | spin_lock(&l3->list_lock); | |
3493 | ||
b28a02de | 3494 | list_for_each(q, &l3->slabs_full) { |
e498be7d CL |
3495 | slabp = list_entry(q, struct slab, list); |
3496 | if (slabp->inuse != cachep->num && !error) | |
3497 | error = "slabs_full accounting error"; | |
3498 | active_objs += cachep->num; | |
3499 | active_slabs++; | |
3500 | } | |
b28a02de | 3501 | list_for_each(q, &l3->slabs_partial) { |
e498be7d CL |
3502 | slabp = list_entry(q, struct slab, list); |
3503 | if (slabp->inuse == cachep->num && !error) | |
3504 | error = "slabs_partial inuse accounting error"; | |
3505 | if (!slabp->inuse && !error) | |
3506 | error = "slabs_partial/inuse accounting error"; | |
3507 | active_objs += slabp->inuse; | |
3508 | active_slabs++; | |
3509 | } | |
b28a02de | 3510 | list_for_each(q, &l3->slabs_free) { |
e498be7d CL |
3511 | slabp = list_entry(q, struct slab, list); |
3512 | if (slabp->inuse && !error) | |
3513 | error = "slabs_free/inuse accounting error"; | |
3514 | num_slabs++; | |
3515 | } | |
3516 | free_objects += l3->free_objects; | |
3517 | shared_avail += l3->shared->avail; | |
3518 | ||
3519 | spin_unlock(&l3->list_lock); | |
1da177e4 | 3520 | } |
b28a02de PE |
3521 | num_slabs += active_slabs; |
3522 | num_objs = num_slabs * cachep->num; | |
e498be7d | 3523 | if (num_objs - active_objs != free_objects && !error) |
1da177e4 LT |
3524 | error = "free_objects accounting error"; |
3525 | ||
b28a02de | 3526 | name = cachep->name; |
1da177e4 LT |
3527 | if (error) |
3528 | printk(KERN_ERR "slab: cache %s error: %s\n", name, error); | |
3529 | ||
3530 | seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", | |
b28a02de PE |
3531 | name, active_objs, num_objs, cachep->objsize, |
3532 | cachep->num, (1 << cachep->gfporder)); | |
1da177e4 | 3533 | seq_printf(m, " : tunables %4u %4u %4u", |
b28a02de | 3534 | cachep->limit, cachep->batchcount, cachep->shared); |
e498be7d | 3535 | seq_printf(m, " : slabdata %6lu %6lu %6lu", |
b28a02de | 3536 | active_slabs, num_slabs, shared_avail); |
1da177e4 | 3537 | #if STATS |
b28a02de | 3538 | { /* list3 stats */ |
1da177e4 LT |
3539 | unsigned long high = cachep->high_mark; |
3540 | unsigned long allocs = cachep->num_allocations; | |
3541 | unsigned long grown = cachep->grown; | |
3542 | unsigned long reaped = cachep->reaped; | |
3543 | unsigned long errors = cachep->errors; | |
3544 | unsigned long max_freeable = cachep->max_freeable; | |
1da177e4 | 3545 | unsigned long node_allocs = cachep->node_allocs; |
e498be7d | 3546 | unsigned long node_frees = cachep->node_frees; |
1da177e4 | 3547 | |
e498be7d | 3548 | seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu \ |
b28a02de | 3549 | %4lu %4lu %4lu %4lu", allocs, high, grown, reaped, errors, max_freeable, node_allocs, node_frees); |
1da177e4 LT |
3550 | } |
3551 | /* cpu stats */ | |
3552 | { | |
3553 | unsigned long allochit = atomic_read(&cachep->allochit); | |
3554 | unsigned long allocmiss = atomic_read(&cachep->allocmiss); | |
3555 | unsigned long freehit = atomic_read(&cachep->freehit); | |
3556 | unsigned long freemiss = atomic_read(&cachep->freemiss); | |
3557 | ||
3558 | seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu", | |
b28a02de | 3559 | allochit, allocmiss, freehit, freemiss); |
1da177e4 LT |
3560 | } |
3561 | #endif | |
3562 | seq_putc(m, '\n'); | |
3563 | spin_unlock_irq(&cachep->spinlock); | |
3564 | return 0; | |
3565 | } | |
3566 | ||
3567 | /* | |
3568 | * slabinfo_op - iterator that generates /proc/slabinfo | |
3569 | * | |
3570 | * Output layout: | |
3571 | * cache-name | |
3572 | * num-active-objs | |
3573 | * total-objs | |
3574 | * object size | |
3575 | * num-active-slabs | |
3576 | * total-slabs | |
3577 | * num-pages-per-slab | |
3578 | * + further values on SMP and with statistics enabled | |
3579 | */ | |
3580 | ||
3581 | struct seq_operations slabinfo_op = { | |
b28a02de PE |
3582 | .start = s_start, |
3583 | .next = s_next, | |
3584 | .stop = s_stop, | |
3585 | .show = s_show, | |
1da177e4 LT |
3586 | }; |
3587 | ||
3588 | #define MAX_SLABINFO_WRITE 128 | |
3589 | /** | |
3590 | * slabinfo_write - Tuning for the slab allocator | |
3591 | * @file: unused | |
3592 | * @buffer: user buffer | |
3593 | * @count: data length | |
3594 | * @ppos: unused | |
3595 | */ | |
b28a02de PE |
3596 | ssize_t slabinfo_write(struct file *file, const char __user * buffer, |
3597 | size_t count, loff_t *ppos) | |
1da177e4 | 3598 | { |
b28a02de | 3599 | char kbuf[MAX_SLABINFO_WRITE + 1], *tmp; |
1da177e4 LT |
3600 | int limit, batchcount, shared, res; |
3601 | struct list_head *p; | |
b28a02de | 3602 | |
1da177e4 LT |
3603 | if (count > MAX_SLABINFO_WRITE) |
3604 | return -EINVAL; | |
3605 | if (copy_from_user(&kbuf, buffer, count)) | |
3606 | return -EFAULT; | |
b28a02de | 3607 | kbuf[MAX_SLABINFO_WRITE] = '\0'; |
1da177e4 LT |
3608 | |
3609 | tmp = strchr(kbuf, ' '); | |
3610 | if (!tmp) | |
3611 | return -EINVAL; | |
3612 | *tmp = '\0'; | |
3613 | tmp++; | |
3614 | if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3) | |
3615 | return -EINVAL; | |
3616 | ||
3617 | /* Find the cache in the chain of caches. */ | |
fc0abb14 | 3618 | mutex_lock(&cache_chain_mutex); |
1da177e4 | 3619 | res = -EINVAL; |
b28a02de | 3620 | list_for_each(p, &cache_chain) { |
1da177e4 LT |
3621 | kmem_cache_t *cachep = list_entry(p, kmem_cache_t, next); |
3622 | ||
3623 | if (!strcmp(cachep->name, kbuf)) { | |
3624 | if (limit < 1 || | |
3625 | batchcount < 1 || | |
b28a02de | 3626 | batchcount > limit || shared < 0) { |
e498be7d | 3627 | res = 0; |
1da177e4 | 3628 | } else { |
e498be7d | 3629 | res = do_tune_cpucache(cachep, limit, |
b28a02de | 3630 | batchcount, shared); |
1da177e4 LT |
3631 | } |
3632 | break; | |
3633 | } | |
3634 | } | |
fc0abb14 | 3635 | mutex_unlock(&cache_chain_mutex); |
1da177e4 LT |
3636 | if (res >= 0) |
3637 | res = count; | |
3638 | return res; | |
3639 | } | |
3640 | #endif | |
3641 | ||
00e145b6 MS |
3642 | /** |
3643 | * ksize - get the actual amount of memory allocated for a given object | |
3644 | * @objp: Pointer to the object | |
3645 | * | |
3646 | * kmalloc may internally round up allocations and return more memory | |
3647 | * than requested. ksize() can be used to determine the actual amount of | |
3648 | * memory allocated. The caller may use this additional memory, even though | |
3649 | * a smaller amount of memory was initially specified with the kmalloc call. | |
3650 | * The caller must guarantee that objp points to a valid object previously | |
3651 | * allocated with either kmalloc() or kmem_cache_alloc(). The object | |
3652 | * must not be freed during the duration of the call. | |
3653 | */ | |
1da177e4 LT |
3654 | unsigned int ksize(const void *objp) |
3655 | { | |
00e145b6 MS |
3656 | if (unlikely(objp == NULL)) |
3657 | return 0; | |
1da177e4 | 3658 | |
065d41cb | 3659 | return obj_reallen(page_get_cache(virt_to_page(objp))); |
1da177e4 | 3660 | } |