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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Ingo Molnarfc0abb12006-01-18 17:42:33 -080071 * The global cache-chain is protected by the mutex 'cache_chain_mutex'.
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 * 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 *
Christoph Lametere498be72005-09-09 13:03:32 -070078 * 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.
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 */
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>
Paulo Marques543537b2005-06-23 00:09:02 -0700104#include <linux/string.h>
Christoph Lametere498be72005-09-09 13:03:32 -0700105#include <linux/nodemask.h>
Christoph Lameterdc85da12006-01-18 17:42:36 -0800106#include <linux/mempolicy.h>
Ingo Molnarfc0abb12006-01-18 17:42:33 -0800107#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108
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
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135/* 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
Kyle Moffettfa5b08d2005-09-03 15:55:03 -0700203typedef unsigned int kmem_bufctl_t;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204#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 */
211static 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 */
220struct slab {
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800221 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;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227};
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 */
245struct slab_rcu {
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800246 struct rcu_head head;
247 kmem_cache_t *cachep;
248 void *addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249};
250
251/*
252 * struct array_cache
253 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 * 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 */
263struct array_cache {
264 unsigned int avail;
265 unsigned int limit;
266 unsigned int batchcount;
267 unsigned int touched;
Christoph Lametere498be72005-09-09 13:03:32 -0700268 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 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275};
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
281struct arraycache_init {
282 struct array_cache cache;
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800283 void *entries[BOOT_CPUCACHE_ENTRIES];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284};
285
286/*
Christoph Lametere498be72005-09-09 13:03:32 -0700287 * The slab lists for all objects.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700288 */
289struct kmem_list3 {
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800290 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 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300};
301
Christoph Lametere498be72005-09-09 13:03:32 -0700302/*
303 * Need this for bootstrapping a per node allocator.
304 */
305#define NUM_INIT_LISTS (2 * MAX_NUMNODES + 1)
306struct 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)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310
Christoph Lametere498be72005-09-09 13:03:32 -0700311/*
Ivan Kokshaysky7243cc02005-09-22 21:43:58 -0700312 * This function must be completely optimized away if
Christoph Lametere498be72005-09-09 13:03:32 -0700313 * a constant is passed to it. Mostly the same as
314 * what is in linux/slab.h except it returns an
315 * index.
316 */
Ivan Kokshaysky7243cc02005-09-22 21:43:58 -0700317static __always_inline int index_of(const size_t size)
Christoph Lametere498be72005-09-09 13:03:32 -0700318{
Steven Rostedt5ec8a842006-02-01 03:05:44 -0800319 extern void __bad_size(void);
320
Christoph Lametere498be72005-09-09 13:03:32 -0700321 if (__builtin_constant_p(size)) {
322 int i = 0;
323
324#define CACHE(x) \
325 if (size <=x) \
326 return i; \
327 else \
328 i++;
329#include "linux/kmalloc_sizes.h"
330#undef CACHE
Steven Rostedt5ec8a842006-02-01 03:05:44 -0800331 __bad_size();
Ivan Kokshaysky7243cc02005-09-22 21:43:58 -0700332 } else
Steven Rostedt5ec8a842006-02-01 03:05:44 -0800333 __bad_size();
Christoph Lametere498be72005-09-09 13:03:32 -0700334 return 0;
335}
336
337#define INDEX_AC index_of(sizeof(struct arraycache_init))
338#define INDEX_L3 index_of(sizeof(struct kmem_list3))
339
340static inline void kmem_list3_init(struct kmem_list3 *parent)
341{
342 INIT_LIST_HEAD(&parent->slabs_full);
343 INIT_LIST_HEAD(&parent->slabs_partial);
344 INIT_LIST_HEAD(&parent->slabs_free);
345 parent->shared = NULL;
346 parent->alien = NULL;
347 spin_lock_init(&parent->list_lock);
348 parent->free_objects = 0;
349 parent->free_touched = 0;
350}
351
352#define MAKE_LIST(cachep, listp, slab, nodeid) \
353 do { \
354 INIT_LIST_HEAD(listp); \
355 list_splice(&(cachep->nodelists[nodeid]->slab), listp); \
356 } while (0)
357
358#define MAKE_ALL_LISTS(cachep, ptr, nodeid) \
359 do { \
360 MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid); \
361 MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \
362 MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid); \
363 } while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364
365/*
366 * kmem_cache_t
367 *
368 * manages a cache.
369 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800370
Pekka J Enberg2109a2d2005-11-07 00:58:01 -0800371struct kmem_cache {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372/* 1) per-cpu data, touched during every alloc/free */
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800373 struct array_cache *array[NR_CPUS];
374 unsigned int batchcount;
375 unsigned int limit;
376 unsigned int shared;
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800377 unsigned int buffer_size;
Christoph Lametere498be72005-09-09 13:03:32 -0700378/* 2) touched by every alloc & free from the backend */
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800379 struct kmem_list3 *nodelists[MAX_NUMNODES];
380 unsigned int flags; /* constant flags */
381 unsigned int num; /* # of objs per slab */
382 spinlock_t spinlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383
384/* 3) cache_grow/shrink */
385 /* order of pgs per slab (2^n) */
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800386 unsigned int gfporder;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387
388 /* force GFP flags, e.g. GFP_DMA */
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800389 gfp_t gfpflags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800391 size_t colour; /* cache colouring range */
392 unsigned int colour_off; /* colour offset */
393 unsigned int colour_next; /* cache colouring */
394 kmem_cache_t *slabp_cache;
395 unsigned int slab_size;
396 unsigned int dflags; /* dynamic flags */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397
398 /* constructor func */
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800399 void (*ctor) (void *, kmem_cache_t *, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400
401 /* de-constructor func */
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800402 void (*dtor) (void *, kmem_cache_t *, unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403
404/* 4) cache creation/removal */
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800405 const char *name;
406 struct list_head next;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407
408/* 5) statistics */
409#if STATS
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800410 unsigned long num_active;
411 unsigned long num_allocations;
412 unsigned long high_mark;
413 unsigned long grown;
414 unsigned long reaped;
415 unsigned long errors;
416 unsigned long max_freeable;
417 unsigned long node_allocs;
418 unsigned long node_frees;
419 atomic_t allochit;
420 atomic_t allocmiss;
421 atomic_t freehit;
422 atomic_t freemiss;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423#endif
424#if DEBUG
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800425 /*
426 * If debugging is enabled, then the allocator can add additional
427 * fields and/or padding to every object. buffer_size contains the total
428 * object size including these internal fields, the following two
429 * variables contain the offset to the user object and its size.
430 */
431 int obj_offset;
432 int obj_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433#endif
434};
435
436#define CFLGS_OFF_SLAB (0x80000000UL)
437#define OFF_SLAB(x) ((x)->flags & CFLGS_OFF_SLAB)
438
439#define BATCHREFILL_LIMIT 16
440/* Optimization question: fewer reaps means less
441 * probability for unnessary cpucache drain/refill cycles.
442 *
Adrian Bunkdc6f3f22005-11-08 16:44:08 +0100443 * OTOH the cpuarrays can contain lots of objects,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 * which could lock up otherwise freeable slabs.
445 */
446#define REAPTIMEOUT_CPUC (2*HZ)
447#define REAPTIMEOUT_LIST3 (4*HZ)
448
449#if STATS
450#define STATS_INC_ACTIVE(x) ((x)->num_active++)
451#define STATS_DEC_ACTIVE(x) ((x)->num_active--)
452#define STATS_INC_ALLOCED(x) ((x)->num_allocations++)
453#define STATS_INC_GROWN(x) ((x)->grown++)
454#define STATS_INC_REAPED(x) ((x)->reaped++)
455#define STATS_SET_HIGH(x) do { if ((x)->num_active > (x)->high_mark) \
456 (x)->high_mark = (x)->num_active; \
457 } while (0)
458#define STATS_INC_ERR(x) ((x)->errors++)
459#define STATS_INC_NODEALLOCS(x) ((x)->node_allocs++)
Christoph Lametere498be72005-09-09 13:03:32 -0700460#define STATS_INC_NODEFREES(x) ((x)->node_frees++)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461#define STATS_SET_FREEABLE(x, i) \
462 do { if ((x)->max_freeable < i) \
463 (x)->max_freeable = i; \
464 } while (0)
465
466#define STATS_INC_ALLOCHIT(x) atomic_inc(&(x)->allochit)
467#define STATS_INC_ALLOCMISS(x) atomic_inc(&(x)->allocmiss)
468#define STATS_INC_FREEHIT(x) atomic_inc(&(x)->freehit)
469#define STATS_INC_FREEMISS(x) atomic_inc(&(x)->freemiss)
470#else
471#define STATS_INC_ACTIVE(x) do { } while (0)
472#define STATS_DEC_ACTIVE(x) do { } while (0)
473#define STATS_INC_ALLOCED(x) do { } while (0)
474#define STATS_INC_GROWN(x) do { } while (0)
475#define STATS_INC_REAPED(x) do { } while (0)
476#define STATS_SET_HIGH(x) do { } while (0)
477#define STATS_INC_ERR(x) do { } while (0)
478#define STATS_INC_NODEALLOCS(x) do { } while (0)
Christoph Lametere498be72005-09-09 13:03:32 -0700479#define STATS_INC_NODEFREES(x) do { } while (0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700480#define STATS_SET_FREEABLE(x, i) \
481 do { } while (0)
482
483#define STATS_INC_ALLOCHIT(x) do { } while (0)
484#define STATS_INC_ALLOCMISS(x) do { } while (0)
485#define STATS_INC_FREEHIT(x) do { } while (0)
486#define STATS_INC_FREEMISS(x) do { } while (0)
487#endif
488
489#if DEBUG
490/* Magic nums for obj red zoning.
491 * Placed in the first word before and the first word after an obj.
492 */
493#define RED_INACTIVE 0x5A2CF071UL /* when obj is inactive */
494#define RED_ACTIVE 0x170FC2A5UL /* when obj is active */
495
496/* ...and for poisoning */
497#define POISON_INUSE 0x5a /* for use-uninitialised poisoning */
498#define POISON_FREE 0x6b /* for use-after-free poisoning */
499#define POISON_END 0xa5 /* end-byte of poisoning */
500
501/* memory layout of objects:
502 * 0 : objp
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800503 * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504 * the end of an object is aligned with the end of the real
505 * allocation. Catches writes behind the end of the allocation.
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800506 * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507 * redzone word.
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800508 * cachep->obj_offset: The real object.
509 * cachep->buffer_size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long]
510 * cachep->buffer_size - 1* BYTES_PER_WORD: last caller address [BYTES_PER_WORD long]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700511 */
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800512static int obj_offset(kmem_cache_t *cachep)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513{
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800514 return cachep->obj_offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515}
516
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800517static int obj_size(kmem_cache_t *cachep)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518{
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800519 return cachep->obj_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700520}
521
522static unsigned long *dbg_redzone1(kmem_cache_t *cachep, void *objp)
523{
524 BUG_ON(!(cachep->flags & SLAB_RED_ZONE));
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800525 return (unsigned long*) (objp+obj_offset(cachep)-BYTES_PER_WORD);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526}
527
528static unsigned long *dbg_redzone2(kmem_cache_t *cachep, void *objp)
529{
530 BUG_ON(!(cachep->flags & SLAB_RED_ZONE));
531 if (cachep->flags & SLAB_STORE_USER)
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800532 return (unsigned long *)(objp + cachep->buffer_size -
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800533 2 * BYTES_PER_WORD);
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800534 return (unsigned long *)(objp + cachep->buffer_size - BYTES_PER_WORD);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535}
536
537static void **dbg_userword(kmem_cache_t *cachep, void *objp)
538{
539 BUG_ON(!(cachep->flags & SLAB_STORE_USER));
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800540 return (void **)(objp + cachep->buffer_size - BYTES_PER_WORD);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541}
542
543#else
544
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800545#define obj_offset(x) 0
546#define obj_size(cachep) (cachep->buffer_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547#define dbg_redzone1(cachep, objp) ({BUG(); (unsigned long *)NULL;})
548#define dbg_redzone2(cachep, objp) ({BUG(); (unsigned long *)NULL;})
549#define dbg_userword(cachep, objp) ({BUG(); (void **)NULL;})
550
551#endif
552
553/*
554 * Maximum size of an obj (in 2^order pages)
555 * and absolute limit for the gfp order.
556 */
557#if defined(CONFIG_LARGE_ALLOCS)
558#define MAX_OBJ_ORDER 13 /* up to 32Mb */
559#define MAX_GFP_ORDER 13 /* up to 32Mb */
560#elif defined(CONFIG_MMU)
561#define MAX_OBJ_ORDER 5 /* 32 pages */
562#define MAX_GFP_ORDER 5 /* 32 pages */
563#else
564#define MAX_OBJ_ORDER 8 /* up to 1Mb */
565#define MAX_GFP_ORDER 8 /* up to 1Mb */
566#endif
567
568/*
569 * Do not go above this order unless 0 objects fit into the slab.
570 */
571#define BREAK_GFP_ORDER_HI 1
572#define BREAK_GFP_ORDER_LO 0
573static int slab_break_gfp_order = BREAK_GFP_ORDER_LO;
574
Pekka Enberg065d41c2005-11-13 16:06:46 -0800575/* Functions for storing/retrieving the cachep and or slab from the
Linus Torvalds1da177e2005-04-16 15:20:36 -0700576 * global 'mem_map'. These are used to find the slab an obj belongs to.
577 * With kfree(), these are used to find the cache which an obj belongs to.
578 */
Pekka Enberg065d41c2005-11-13 16:06:46 -0800579static inline void page_set_cache(struct page *page, struct kmem_cache *cache)
580{
581 page->lru.next = (struct list_head *)cache;
582}
583
584static inline struct kmem_cache *page_get_cache(struct page *page)
585{
586 return (struct kmem_cache *)page->lru.next;
587}
588
589static inline void page_set_slab(struct page *page, struct slab *slab)
590{
591 page->lru.prev = (struct list_head *)slab;
592}
593
594static inline struct slab *page_get_slab(struct page *page)
595{
596 return (struct slab *)page->lru.prev;
597}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598
599/* These are the default caches for kmalloc. Custom caches can have other sizes. */
600struct cache_sizes malloc_sizes[] = {
601#define CACHE(x) { .cs_size = (x) },
602#include <linux/kmalloc_sizes.h>
603 CACHE(ULONG_MAX)
604#undef CACHE
605};
606EXPORT_SYMBOL(malloc_sizes);
607
608/* Must match cache_sizes above. Out of line to keep cache footprint low. */
609struct cache_names {
610 char *name;
611 char *name_dma;
612};
613
614static struct cache_names __initdata cache_names[] = {
615#define CACHE(x) { .name = "size-" #x, .name_dma = "size-" #x "(DMA)" },
616#include <linux/kmalloc_sizes.h>
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800617 {NULL,}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618#undef CACHE
619};
620
621static struct arraycache_init initarray_cache __initdata =
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800622 { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700623static struct arraycache_init initarray_generic =
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800624 { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625
626/* internal cache of cache description objs */
627static kmem_cache_t cache_cache = {
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800628 .batchcount = 1,
629 .limit = BOOT_CPUCACHE_ENTRIES,
630 .shared = 1,
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800631 .buffer_size = sizeof(kmem_cache_t),
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800632 .flags = SLAB_NO_REAP,
633 .spinlock = SPIN_LOCK_UNLOCKED,
634 .name = "kmem_cache",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635#if DEBUG
Manfred Spraul3dafccf2006-02-01 03:05:42 -0800636 .obj_size = sizeof(kmem_cache_t),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637#endif
638};
639
640/* Guard access to the cache-chain. */
Ingo Molnarfc0abb12006-01-18 17:42:33 -0800641static DEFINE_MUTEX(cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642static struct list_head cache_chain;
643
644/*
645 * vm_enough_memory() looks at this to determine how many
646 * slab-allocated pages are possibly freeable under pressure
647 *
648 * SLAB_RECLAIM_ACCOUNT turns this on per-slab
649 */
650atomic_t slab_reclaim_pages;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651
652/*
653 * chicken and egg problem: delay the per-cpu array allocation
654 * until the general caches are up.
655 */
656static enum {
657 NONE,
Christoph Lametere498be72005-09-09 13:03:32 -0700658 PARTIAL_AC,
659 PARTIAL_L3,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 FULL
661} g_cpucache_up;
662
663static DEFINE_PER_CPU(struct work_struct, reap_work);
664
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800665static void free_block(kmem_cache_t *cachep, void **objpp, int len, int node);
666static void enable_cpucache(kmem_cache_t *cachep);
667static void cache_reap(void *unused);
Christoph Lametere498be72005-09-09 13:03:32 -0700668static int __node_shrink(kmem_cache_t *cachep, int node);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669
670static inline struct array_cache *ac_data(kmem_cache_t *cachep)
671{
672 return cachep->array[smp_processor_id()];
673}
674
Al Virodd0fc662005-10-07 07:46:04 +0100675static inline kmem_cache_t *__find_general_cachep(size_t size, gfp_t gfpflags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676{
677 struct cache_sizes *csizep = malloc_sizes;
678
679#if DEBUG
680 /* This happens if someone tries to call
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800681 * kmem_cache_create(), or __kmalloc(), before
682 * the generic caches are initialized.
683 */
Alok Katariac7e43c72005-09-14 12:17:53 -0700684 BUG_ON(malloc_sizes[INDEX_AC].cs_cachep == NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685#endif
686 while (size > csizep->cs_size)
687 csizep++;
688
689 /*
Martin Hicks0abf40c2005-09-03 15:54:54 -0700690 * Really subtle: The last entry with cs->cs_size==ULONG_MAX
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691 * has cs_{dma,}cachep==NULL. Thus no special case
692 * for large kmalloc calls required.
693 */
694 if (unlikely(gfpflags & GFP_DMA))
695 return csizep->cs_dmacachep;
696 return csizep->cs_cachep;
697}
698
Al Virodd0fc662005-10-07 07:46:04 +0100699kmem_cache_t *kmem_find_general_cachep(size_t size, gfp_t gfpflags)
Manfred Spraul97e2bde2005-05-01 08:58:38 -0700700{
701 return __find_general_cachep(size, gfpflags);
702}
703EXPORT_SYMBOL(kmem_find_general_cachep);
704
Steven Rostedtfbaccac2006-02-01 03:05:45 -0800705static size_t slab_mgmt_size(size_t nr_objs, size_t align)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706{
Steven Rostedtfbaccac2006-02-01 03:05:45 -0800707 return ALIGN(sizeof(struct slab)+nr_objs*sizeof(kmem_bufctl_t), align);
708}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709
Steven Rostedtfbaccac2006-02-01 03:05:45 -0800710/* Calculate the number of objects and left-over bytes for a given
711 buffer size. */
712static void cache_estimate(unsigned long gfporder, size_t buffer_size,
713 size_t align, int flags, size_t *left_over,
714 unsigned int *num)
715{
716 int nr_objs;
717 size_t mgmt_size;
718 size_t slab_size = PAGE_SIZE << gfporder;
719
720 /*
721 * The slab management structure can be either off the slab or
722 * on it. For the latter case, the memory allocated for a
723 * slab is used for:
724 *
725 * - The struct slab
726 * - One kmem_bufctl_t for each object
727 * - Padding to respect alignment of @align
728 * - @buffer_size bytes for each object
729 *
730 * If the slab management structure is off the slab, then the
731 * alignment will already be calculated into the size. Because
732 * the slabs are all pages aligned, the objects will be at the
733 * correct alignment when allocated.
734 */
735 if (flags & CFLGS_OFF_SLAB) {
736 mgmt_size = 0;
737 nr_objs = slab_size / buffer_size;
738
739 if (nr_objs > SLAB_LIMIT)
740 nr_objs = SLAB_LIMIT;
741 } else {
742 /*
743 * Ignore padding for the initial guess. The padding
744 * is at most @align-1 bytes, and @buffer_size is at
745 * least @align. In the worst case, this result will
746 * be one greater than the number of objects that fit
747 * into the memory allocation when taking the padding
748 * into account.
749 */
750 nr_objs = (slab_size - sizeof(struct slab)) /
751 (buffer_size + sizeof(kmem_bufctl_t));
752
753 /*
754 * This calculated number will be either the right
755 * amount, or one greater than what we want.
756 */
757 if (slab_mgmt_size(nr_objs, align) + nr_objs*buffer_size
758 > slab_size)
759 nr_objs--;
760
761 if (nr_objs > SLAB_LIMIT)
762 nr_objs = SLAB_LIMIT;
763
764 mgmt_size = slab_mgmt_size(nr_objs, align);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 }
Steven Rostedtfbaccac2006-02-01 03:05:45 -0800766 *num = nr_objs;
767 *left_over = slab_size - nr_objs*buffer_size - mgmt_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768}
769
770#define slab_error(cachep, msg) __slab_error(__FUNCTION__, cachep, msg)
771
772static void __slab_error(const char *function, kmem_cache_t *cachep, char *msg)
773{
774 printk(KERN_ERR "slab error in %s(): cache `%s': %s\n",
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800775 function, cachep->name, msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 dump_stack();
777}
778
779/*
780 * Initiate the reap timer running on the target CPU. We run at around 1 to 2Hz
781 * via the workqueue/eventd.
782 * Add the CPU number into the expiration time to minimize the possibility of
783 * the CPUs getting into lockstep and contending for the global cache chain
784 * lock.
785 */
786static void __devinit start_cpu_timer(int cpu)
787{
788 struct work_struct *reap_work = &per_cpu(reap_work, cpu);
789
790 /*
791 * When this gets called from do_initcalls via cpucache_init(),
792 * init_workqueues() has already run, so keventd will be setup
793 * at that time.
794 */
795 if (keventd_up() && reap_work->func == NULL) {
796 INIT_WORK(reap_work, cache_reap, NULL);
797 schedule_delayed_work_on(cpu, reap_work, HZ + 3 * cpu);
798 }
799}
800
Christoph Lametere498be72005-09-09 13:03:32 -0700801static struct array_cache *alloc_arraycache(int node, int entries,
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800802 int batchcount)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700803{
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800804 int memsize = sizeof(void *) * entries + sizeof(struct array_cache);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805 struct array_cache *nc = NULL;
806
Christoph Lametere498be72005-09-09 13:03:32 -0700807 nc = kmalloc_node(memsize, GFP_KERNEL, node);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808 if (nc) {
809 nc->avail = 0;
810 nc->limit = entries;
811 nc->batchcount = batchcount;
812 nc->touched = 0;
Christoph Lametere498be72005-09-09 13:03:32 -0700813 spin_lock_init(&nc->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814 }
815 return nc;
816}
817
Christoph Lametere498be72005-09-09 13:03:32 -0700818#ifdef CONFIG_NUMA
Christoph Lameterdc85da12006-01-18 17:42:36 -0800819static void *__cache_alloc_node(kmem_cache_t *, gfp_t, int);
820
Christoph Lametere498be72005-09-09 13:03:32 -0700821static inline struct array_cache **alloc_alien_cache(int node, int limit)
822{
823 struct array_cache **ac_ptr;
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800824 int memsize = sizeof(void *) * MAX_NUMNODES;
Christoph Lametere498be72005-09-09 13:03:32 -0700825 int i;
826
827 if (limit > 1)
828 limit = 12;
829 ac_ptr = kmalloc_node(memsize, GFP_KERNEL, node);
830 if (ac_ptr) {
831 for_each_node(i) {
832 if (i == node || !node_online(i)) {
833 ac_ptr[i] = NULL;
834 continue;
835 }
836 ac_ptr[i] = alloc_arraycache(node, limit, 0xbaadf00d);
837 if (!ac_ptr[i]) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800838 for (i--; i <= 0; i--)
Christoph Lametere498be72005-09-09 13:03:32 -0700839 kfree(ac_ptr[i]);
840 kfree(ac_ptr);
841 return NULL;
842 }
843 }
844 }
845 return ac_ptr;
846}
847
848static inline void free_alien_cache(struct array_cache **ac_ptr)
849{
850 int i;
851
852 if (!ac_ptr)
853 return;
854
855 for_each_node(i)
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800856 kfree(ac_ptr[i]);
Christoph Lametere498be72005-09-09 13:03:32 -0700857
858 kfree(ac_ptr);
859}
860
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800861static inline void __drain_alien_cache(kmem_cache_t *cachep,
862 struct array_cache *ac, int node)
Christoph Lametere498be72005-09-09 13:03:32 -0700863{
864 struct kmem_list3 *rl3 = cachep->nodelists[node];
865
866 if (ac->avail) {
867 spin_lock(&rl3->list_lock);
Christoph Lameterff694162005-09-22 21:44:02 -0700868 free_block(cachep, ac->entry, ac->avail, node);
Christoph Lametere498be72005-09-09 13:03:32 -0700869 ac->avail = 0;
870 spin_unlock(&rl3->list_lock);
871 }
872}
873
874static void drain_alien_cache(kmem_cache_t *cachep, struct kmem_list3 *l3)
875{
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800876 int i = 0;
Christoph Lametere498be72005-09-09 13:03:32 -0700877 struct array_cache *ac;
878 unsigned long flags;
879
880 for_each_online_node(i) {
881 ac = l3->alien[i];
882 if (ac) {
883 spin_lock_irqsave(&ac->lock, flags);
884 __drain_alien_cache(cachep, ac, i);
885 spin_unlock_irqrestore(&ac->lock, flags);
886 }
887 }
888}
889#else
890#define alloc_alien_cache(node, limit) do { } while (0)
891#define free_alien_cache(ac_ptr) do { } while (0)
892#define drain_alien_cache(cachep, l3) do { } while (0)
893#endif
894
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895static int __devinit cpuup_callback(struct notifier_block *nfb,
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800896 unsigned long action, void *hcpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700897{
898 long cpu = (long)hcpu;
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800899 kmem_cache_t *cachep;
Christoph Lametere498be72005-09-09 13:03:32 -0700900 struct kmem_list3 *l3 = NULL;
901 int node = cpu_to_node(cpu);
902 int memsize = sizeof(struct kmem_list3);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903
904 switch (action) {
905 case CPU_UP_PREPARE:
Ingo Molnarfc0abb12006-01-18 17:42:33 -0800906 mutex_lock(&cache_chain_mutex);
Christoph Lametere498be72005-09-09 13:03:32 -0700907 /* we need to do this right in the beginning since
908 * alloc_arraycache's are going to use this list.
909 * kmalloc_node allows us to add the slab to the right
910 * kmem_list3 and not this cpu's kmem_list3
911 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912
Christoph Lametere498be72005-09-09 13:03:32 -0700913 list_for_each_entry(cachep, &cache_chain, next) {
914 /* setup the size64 kmemlist for cpu before we can
915 * begin anything. Make sure some other cpu on this
916 * node has not already allocated this
917 */
918 if (!cachep->nodelists[node]) {
919 if (!(l3 = kmalloc_node(memsize,
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800920 GFP_KERNEL, node)))
Christoph Lametere498be72005-09-09 13:03:32 -0700921 goto bad;
922 kmem_list3_init(l3);
923 l3->next_reap = jiffies + REAPTIMEOUT_LIST3 +
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800924 ((unsigned long)cachep) % REAPTIMEOUT_LIST3;
Christoph Lametere498be72005-09-09 13:03:32 -0700925
926 cachep->nodelists[node] = l3;
927 }
928
929 spin_lock_irq(&cachep->nodelists[node]->list_lock);
930 cachep->nodelists[node]->free_limit =
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800931 (1 + nr_cpus_node(node)) *
932 cachep->batchcount + cachep->num;
Christoph Lametere498be72005-09-09 13:03:32 -0700933 spin_unlock_irq(&cachep->nodelists[node]->list_lock);
934 }
935
936 /* Now we can go ahead with allocating the shared array's
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800937 & array cache's */
Christoph Lametere498be72005-09-09 13:03:32 -0700938 list_for_each_entry(cachep, &cache_chain, next) {
Tobias Klausercd105df2006-01-08 01:00:59 -0800939 struct array_cache *nc;
940
Christoph Lametere498be72005-09-09 13:03:32 -0700941 nc = alloc_arraycache(node, cachep->limit,
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800942 cachep->batchcount);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943 if (!nc)
944 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 cachep->array[cpu] = nc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700946
Christoph Lametere498be72005-09-09 13:03:32 -0700947 l3 = cachep->nodelists[node];
948 BUG_ON(!l3);
949 if (!l3->shared) {
950 if (!(nc = alloc_arraycache(node,
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800951 cachep->shared *
952 cachep->batchcount,
953 0xbaadf00d)))
954 goto bad;
Christoph Lametere498be72005-09-09 13:03:32 -0700955
956 /* we are serialised from CPU_DEAD or
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800957 CPU_UP_CANCELLED by the cpucontrol lock */
Christoph Lametere498be72005-09-09 13:03:32 -0700958 l3->shared = nc;
959 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700960 }
Ingo Molnarfc0abb12006-01-18 17:42:33 -0800961 mutex_unlock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700962 break;
963 case CPU_ONLINE:
964 start_cpu_timer(cpu);
965 break;
966#ifdef CONFIG_HOTPLUG_CPU
967 case CPU_DEAD:
968 /* fall thru */
969 case CPU_UP_CANCELED:
Ingo Molnarfc0abb12006-01-18 17:42:33 -0800970 mutex_lock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700971
972 list_for_each_entry(cachep, &cache_chain, next) {
973 struct array_cache *nc;
Christoph Lametere498be72005-09-09 13:03:32 -0700974 cpumask_t mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975
Christoph Lametere498be72005-09-09 13:03:32 -0700976 mask = node_to_cpumask(node);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977 spin_lock_irq(&cachep->spinlock);
978 /* cpu is dead; no one can alloc from it. */
979 nc = cachep->array[cpu];
980 cachep->array[cpu] = NULL;
Christoph Lametere498be72005-09-09 13:03:32 -0700981 l3 = cachep->nodelists[node];
982
983 if (!l3)
984 goto unlock_cache;
985
986 spin_lock(&l3->list_lock);
987
988 /* Free limit for this kmem_list3 */
989 l3->free_limit -= cachep->batchcount;
990 if (nc)
Christoph Lameterff694162005-09-22 21:44:02 -0700991 free_block(cachep, nc->entry, nc->avail, node);
Christoph Lametere498be72005-09-09 13:03:32 -0700992
993 if (!cpus_empty(mask)) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -0800994 spin_unlock(&l3->list_lock);
995 goto unlock_cache;
996 }
Christoph Lametere498be72005-09-09 13:03:32 -0700997
998 if (l3->shared) {
999 free_block(cachep, l3->shared->entry,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001000 l3->shared->avail, node);
Christoph Lametere498be72005-09-09 13:03:32 -07001001 kfree(l3->shared);
1002 l3->shared = NULL;
1003 }
1004 if (l3->alien) {
1005 drain_alien_cache(cachep, l3);
1006 free_alien_cache(l3->alien);
1007 l3->alien = NULL;
1008 }
1009
1010 /* free slabs belonging to this node */
1011 if (__node_shrink(cachep, node)) {
1012 cachep->nodelists[node] = NULL;
1013 spin_unlock(&l3->list_lock);
1014 kfree(l3);
1015 } else {
1016 spin_unlock(&l3->list_lock);
1017 }
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001018 unlock_cache:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019 spin_unlock_irq(&cachep->spinlock);
1020 kfree(nc);
1021 }
Ingo Molnarfc0abb12006-01-18 17:42:33 -08001022 mutex_unlock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001023 break;
1024#endif
1025 }
1026 return NOTIFY_OK;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001027 bad:
Ingo Molnarfc0abb12006-01-18 17:42:33 -08001028 mutex_unlock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001029 return NOTIFY_BAD;
1030}
1031
1032static struct notifier_block cpucache_notifier = { &cpuup_callback, NULL, 0 };
1033
Christoph Lametere498be72005-09-09 13:03:32 -07001034/*
1035 * swap the static kmem_list3 with kmalloced memory
1036 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001037static void init_list(kmem_cache_t *cachep, struct kmem_list3 *list, int nodeid)
Christoph Lametere498be72005-09-09 13:03:32 -07001038{
1039 struct kmem_list3 *ptr;
1040
1041 BUG_ON(cachep->nodelists[nodeid] != list);
1042 ptr = kmalloc_node(sizeof(struct kmem_list3), GFP_KERNEL, nodeid);
1043 BUG_ON(!ptr);
1044
1045 local_irq_disable();
1046 memcpy(ptr, list, sizeof(struct kmem_list3));
1047 MAKE_ALL_LISTS(cachep, ptr, nodeid);
1048 cachep->nodelists[nodeid] = ptr;
1049 local_irq_enable();
1050}
1051
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052/* Initialisation.
1053 * Called after the gfp() functions have been enabled, and before smp_init().
1054 */
1055void __init kmem_cache_init(void)
1056{
1057 size_t left_over;
1058 struct cache_sizes *sizes;
1059 struct cache_names *names;
Christoph Lametere498be72005-09-09 13:03:32 -07001060 int i;
1061
1062 for (i = 0; i < NUM_INIT_LISTS; i++) {
1063 kmem_list3_init(&initkmem_list3[i]);
1064 if (i < MAX_NUMNODES)
1065 cache_cache.nodelists[i] = NULL;
1066 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067
1068 /*
1069 * Fragmentation resistance on low memory - only use bigger
1070 * page orders on machines with more than 32MB of memory.
1071 */
1072 if (num_physpages > (32 << 20) >> PAGE_SHIFT)
1073 slab_break_gfp_order = BREAK_GFP_ORDER_HI;
1074
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075 /* Bootstrap is tricky, because several objects are allocated
1076 * from caches that do not exist yet:
1077 * 1) initialize the cache_cache cache: it contains the kmem_cache_t
1078 * structures of all caches, except cache_cache itself: cache_cache
1079 * is statically allocated.
Christoph Lametere498be72005-09-09 13:03:32 -07001080 * Initially an __init data area is used for the head array and the
1081 * kmem_list3 structures, it's replaced with a kmalloc allocated
1082 * array at the end of the bootstrap.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001083 * 2) Create the first kmalloc cache.
Christoph Lametere498be72005-09-09 13:03:32 -07001084 * The kmem_cache_t for the new cache is allocated normally.
1085 * An __init data area is used for the head array.
1086 * 3) Create the remaining kmalloc caches, with minimally sized
1087 * head arrays.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001088 * 4) Replace the __init data head arrays for cache_cache and the first
1089 * kmalloc cache with kmalloc allocated arrays.
Christoph Lametere498be72005-09-09 13:03:32 -07001090 * 5) Replace the __init data for kmem_list3 for cache_cache and
1091 * the other cache's with kmalloc allocated memory.
1092 * 6) Resize the head arrays of the kmalloc caches to their final sizes.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093 */
1094
1095 /* 1) create the cache_cache */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096 INIT_LIST_HEAD(&cache_chain);
1097 list_add(&cache_cache.next, &cache_chain);
1098 cache_cache.colour_off = cache_line_size();
1099 cache_cache.array[smp_processor_id()] = &initarray_cache.cache;
Christoph Lametere498be72005-09-09 13:03:32 -07001100 cache_cache.nodelists[numa_node_id()] = &initkmem_list3[CACHE_CACHE];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001101
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001102 cache_cache.buffer_size = ALIGN(cache_cache.buffer_size, cache_line_size());
Linus Torvalds1da177e2005-04-16 15:20:36 -07001103
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001104 cache_estimate(0, cache_cache.buffer_size, cache_line_size(), 0,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001105 &left_over, &cache_cache.num);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001106 if (!cache_cache.num)
1107 BUG();
1108
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001109 cache_cache.colour = left_over / cache_cache.colour_off;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 cache_cache.colour_next = 0;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001111 cache_cache.slab_size = ALIGN(cache_cache.num * sizeof(kmem_bufctl_t) +
1112 sizeof(struct slab), cache_line_size());
Linus Torvalds1da177e2005-04-16 15:20:36 -07001113
1114 /* 2+3) create the kmalloc caches */
1115 sizes = malloc_sizes;
1116 names = cache_names;
1117
Christoph Lametere498be72005-09-09 13:03:32 -07001118 /* Initialize the caches that provide memory for the array cache
1119 * and the kmem_list3 structures first.
1120 * Without this, further allocations will bug
1121 */
1122
1123 sizes[INDEX_AC].cs_cachep = kmem_cache_create(names[INDEX_AC].name,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001124 sizes[INDEX_AC].cs_size,
1125 ARCH_KMALLOC_MINALIGN,
1126 (ARCH_KMALLOC_FLAGS |
1127 SLAB_PANIC), NULL, NULL);
Christoph Lametere498be72005-09-09 13:03:32 -07001128
1129 if (INDEX_AC != INDEX_L3)
1130 sizes[INDEX_L3].cs_cachep =
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001131 kmem_cache_create(names[INDEX_L3].name,
1132 sizes[INDEX_L3].cs_size,
1133 ARCH_KMALLOC_MINALIGN,
1134 (ARCH_KMALLOC_FLAGS | SLAB_PANIC), NULL,
1135 NULL);
Christoph Lametere498be72005-09-09 13:03:32 -07001136
Linus Torvalds1da177e2005-04-16 15:20:36 -07001137 while (sizes->cs_size != ULONG_MAX) {
Christoph Lametere498be72005-09-09 13:03:32 -07001138 /*
1139 * For performance, all the general caches are L1 aligned.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001140 * This should be particularly beneficial on SMP boxes, as it
1141 * eliminates "false sharing".
1142 * Note for systems short on memory removing the alignment will
Christoph Lametere498be72005-09-09 13:03:32 -07001143 * allow tighter packing of the smaller caches.
1144 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001145 if (!sizes->cs_cachep)
Christoph Lametere498be72005-09-09 13:03:32 -07001146 sizes->cs_cachep = kmem_cache_create(names->name,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001147 sizes->cs_size,
1148 ARCH_KMALLOC_MINALIGN,
1149 (ARCH_KMALLOC_FLAGS
1150 | SLAB_PANIC),
1151 NULL, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152
1153 /* Inc off-slab bufctl limit until the ceiling is hit. */
1154 if (!(OFF_SLAB(sizes->cs_cachep))) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001155 offslab_limit = sizes->cs_size - sizeof(struct slab);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001156 offslab_limit /= sizeof(kmem_bufctl_t);
1157 }
1158
1159 sizes->cs_dmacachep = kmem_cache_create(names->name_dma,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001160 sizes->cs_size,
1161 ARCH_KMALLOC_MINALIGN,
1162 (ARCH_KMALLOC_FLAGS |
1163 SLAB_CACHE_DMA |
1164 SLAB_PANIC), NULL,
1165 NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001166
1167 sizes++;
1168 names++;
1169 }
1170 /* 4) Replace the bootstrap head arrays */
1171 {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001172 void *ptr;
Christoph Lametere498be72005-09-09 13:03:32 -07001173
Linus Torvalds1da177e2005-04-16 15:20:36 -07001174 ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL);
Christoph Lametere498be72005-09-09 13:03:32 -07001175
Linus Torvalds1da177e2005-04-16 15:20:36 -07001176 local_irq_disable();
1177 BUG_ON(ac_data(&cache_cache) != &initarray_cache.cache);
Christoph Lametere498be72005-09-09 13:03:32 -07001178 memcpy(ptr, ac_data(&cache_cache),
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001179 sizeof(struct arraycache_init));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001180 cache_cache.array[smp_processor_id()] = ptr;
1181 local_irq_enable();
Christoph Lametere498be72005-09-09 13:03:32 -07001182
Linus Torvalds1da177e2005-04-16 15:20:36 -07001183 ptr = kmalloc(sizeof(struct arraycache_init), GFP_KERNEL);
Christoph Lametere498be72005-09-09 13:03:32 -07001184
Linus Torvalds1da177e2005-04-16 15:20:36 -07001185 local_irq_disable();
Christoph Lametere498be72005-09-09 13:03:32 -07001186 BUG_ON(ac_data(malloc_sizes[INDEX_AC].cs_cachep)
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001187 != &initarray_generic.cache);
Christoph Lametere498be72005-09-09 13:03:32 -07001188 memcpy(ptr, ac_data(malloc_sizes[INDEX_AC].cs_cachep),
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001189 sizeof(struct arraycache_init));
Christoph Lametere498be72005-09-09 13:03:32 -07001190 malloc_sizes[INDEX_AC].cs_cachep->array[smp_processor_id()] =
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001191 ptr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001192 local_irq_enable();
1193 }
Christoph Lametere498be72005-09-09 13:03:32 -07001194 /* 5) Replace the bootstrap kmem_list3's */
1195 {
1196 int node;
1197 /* Replace the static kmem_list3 structures for the boot cpu */
1198 init_list(&cache_cache, &initkmem_list3[CACHE_CACHE],
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001199 numa_node_id());
Linus Torvalds1da177e2005-04-16 15:20:36 -07001200
Christoph Lametere498be72005-09-09 13:03:32 -07001201 for_each_online_node(node) {
1202 init_list(malloc_sizes[INDEX_AC].cs_cachep,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001203 &initkmem_list3[SIZE_AC + node], node);
Christoph Lametere498be72005-09-09 13:03:32 -07001204
1205 if (INDEX_AC != INDEX_L3) {
1206 init_list(malloc_sizes[INDEX_L3].cs_cachep,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001207 &initkmem_list3[SIZE_L3 + node],
1208 node);
Christoph Lametere498be72005-09-09 13:03:32 -07001209 }
1210 }
1211 }
1212
1213 /* 6) resize the head arrays to their final sizes */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001214 {
1215 kmem_cache_t *cachep;
Ingo Molnarfc0abb12006-01-18 17:42:33 -08001216 mutex_lock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001217 list_for_each_entry(cachep, &cache_chain, next)
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001218 enable_cpucache(cachep);
Ingo Molnarfc0abb12006-01-18 17:42:33 -08001219 mutex_unlock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001220 }
1221
1222 /* Done! */
1223 g_cpucache_up = FULL;
1224
1225 /* Register a cpu startup notifier callback
1226 * that initializes ac_data for all new cpus
1227 */
1228 register_cpu_notifier(&cpucache_notifier);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001229
1230 /* The reap timers are started later, with a module init call:
1231 * That part of the kernel is not yet operational.
1232 */
1233}
1234
1235static int __init cpucache_init(void)
1236{
1237 int cpu;
1238
1239 /*
1240 * Register the timers that return unneeded
1241 * pages to gfp.
1242 */
Christoph Lametere498be72005-09-09 13:03:32 -07001243 for_each_online_cpu(cpu)
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001244 start_cpu_timer(cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001245
1246 return 0;
1247}
1248
1249__initcall(cpucache_init);
1250
1251/*
1252 * Interface to system's page allocator. No need to hold the cache-lock.
1253 *
1254 * If we requested dmaable memory, we will get it. Even if we
1255 * did not request dmaable memory, we might get it, but that
1256 * would be relatively rare and ignorable.
1257 */
Al Virodd0fc662005-10-07 07:46:04 +01001258static void *kmem_getpages(kmem_cache_t *cachep, gfp_t flags, int nodeid)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259{
1260 struct page *page;
1261 void *addr;
1262 int i;
1263
1264 flags |= cachep->gfpflags;
Christoph Lameter50c85a12005-11-13 16:06:47 -08001265 page = alloc_pages_node(nodeid, flags, cachep->gfporder);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001266 if (!page)
1267 return NULL;
1268 addr = page_address(page);
1269
1270 i = (1 << cachep->gfporder);
1271 if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
1272 atomic_add(i, &slab_reclaim_pages);
1273 add_page_state(nr_slab, i);
1274 while (i--) {
1275 SetPageSlab(page);
1276 page++;
1277 }
1278 return addr;
1279}
1280
1281/*
1282 * Interface to system's page release.
1283 */
1284static void kmem_freepages(kmem_cache_t *cachep, void *addr)
1285{
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001286 unsigned long i = (1 << cachep->gfporder);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001287 struct page *page = virt_to_page(addr);
1288 const unsigned long nr_freed = i;
1289
1290 while (i--) {
1291 if (!TestClearPageSlab(page))
1292 BUG();
1293 page++;
1294 }
1295 sub_page_state(nr_slab, nr_freed);
1296 if (current->reclaim_state)
1297 current->reclaim_state->reclaimed_slab += nr_freed;
1298 free_pages((unsigned long)addr, cachep->gfporder);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001299 if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
1300 atomic_sub(1 << cachep->gfporder, &slab_reclaim_pages);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301}
1302
1303static void kmem_rcu_free(struct rcu_head *head)
1304{
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001305 struct slab_rcu *slab_rcu = (struct slab_rcu *)head;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001306 kmem_cache_t *cachep = slab_rcu->cachep;
1307
1308 kmem_freepages(cachep, slab_rcu->addr);
1309 if (OFF_SLAB(cachep))
1310 kmem_cache_free(cachep->slabp_cache, slab_rcu);
1311}
1312
1313#if DEBUG
1314
1315#ifdef CONFIG_DEBUG_PAGEALLOC
1316static void store_stackinfo(kmem_cache_t *cachep, unsigned long *addr,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001317 unsigned long caller)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001318{
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001319 int size = obj_size(cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001320
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001321 addr = (unsigned long *)&((char *)addr)[obj_offset(cachep)];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001323 if (size < 5 * sizeof(unsigned long))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001324 return;
1325
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001326 *addr++ = 0x12345678;
1327 *addr++ = caller;
1328 *addr++ = smp_processor_id();
1329 size -= 3 * sizeof(unsigned long);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001330 {
1331 unsigned long *sptr = &caller;
1332 unsigned long svalue;
1333
1334 while (!kstack_end(sptr)) {
1335 svalue = *sptr++;
1336 if (kernel_text_address(svalue)) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001337 *addr++ = svalue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001338 size -= sizeof(unsigned long);
1339 if (size <= sizeof(unsigned long))
1340 break;
1341 }
1342 }
1343
1344 }
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001345 *addr++ = 0x87654321;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346}
1347#endif
1348
1349static void poison_obj(kmem_cache_t *cachep, void *addr, unsigned char val)
1350{
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001351 int size = obj_size(cachep);
1352 addr = &((char *)addr)[obj_offset(cachep)];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001353
1354 memset(addr, val, size);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001355 *(unsigned char *)(addr + size - 1) = POISON_END;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001356}
1357
1358static void dump_line(char *data, int offset, int limit)
1359{
1360 int i;
1361 printk(KERN_ERR "%03x:", offset);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001362 for (i = 0; i < limit; i++) {
1363 printk(" %02x", (unsigned char)data[offset + i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001364 }
1365 printk("\n");
1366}
1367#endif
1368
1369#if DEBUG
1370
1371static void print_objinfo(kmem_cache_t *cachep, void *objp, int lines)
1372{
1373 int i, size;
1374 char *realobj;
1375
1376 if (cachep->flags & SLAB_RED_ZONE) {
1377 printk(KERN_ERR "Redzone: 0x%lx/0x%lx.\n",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001378 *dbg_redzone1(cachep, objp),
1379 *dbg_redzone2(cachep, objp));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001380 }
1381
1382 if (cachep->flags & SLAB_STORE_USER) {
1383 printk(KERN_ERR "Last user: [<%p>]",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001384 *dbg_userword(cachep, objp));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001385 print_symbol("(%s)",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001386 (unsigned long)*dbg_userword(cachep, objp));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001387 printk("\n");
1388 }
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001389 realobj = (char *)objp + obj_offset(cachep);
1390 size = obj_size(cachep);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001391 for (i = 0; i < size && lines; i += 16, lines--) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001392 int limit;
1393 limit = 16;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001394 if (i + limit > size)
1395 limit = size - i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001396 dump_line(realobj, i, limit);
1397 }
1398}
1399
1400static void check_poison_obj(kmem_cache_t *cachep, void *objp)
1401{
1402 char *realobj;
1403 int size, i;
1404 int lines = 0;
1405
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001406 realobj = (char *)objp + obj_offset(cachep);
1407 size = obj_size(cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001408
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001409 for (i = 0; i < size; i++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001410 char exp = POISON_FREE;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001411 if (i == size - 1)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001412 exp = POISON_END;
1413 if (realobj[i] != exp) {
1414 int limit;
1415 /* Mismatch ! */
1416 /* Print header */
1417 if (lines == 0) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001418 printk(KERN_ERR
1419 "Slab corruption: start=%p, len=%d\n",
1420 realobj, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001421 print_objinfo(cachep, objp, 0);
1422 }
1423 /* Hexdump the affected line */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001424 i = (i / 16) * 16;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001425 limit = 16;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001426 if (i + limit > size)
1427 limit = size - i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001428 dump_line(realobj, i, limit);
1429 i += 16;
1430 lines++;
1431 /* Limit to 5 lines */
1432 if (lines > 5)
1433 break;
1434 }
1435 }
1436 if (lines != 0) {
1437 /* Print some data about the neighboring objects, if they
1438 * exist:
1439 */
Pekka Enberg065d41c2005-11-13 16:06:46 -08001440 struct slab *slabp = page_get_slab(virt_to_page(objp));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001441 int objnr;
1442
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001443 objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001444 if (objnr) {
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001445 objp = slabp->s_mem + (objnr - 1) * cachep->buffer_size;
1446 realobj = (char *)objp + obj_offset(cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001447 printk(KERN_ERR "Prev obj: start=%p, len=%d\n",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001448 realobj, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001449 print_objinfo(cachep, objp, 2);
1450 }
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001451 if (objnr + 1 < cachep->num) {
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001452 objp = slabp->s_mem + (objnr + 1) * cachep->buffer_size;
1453 realobj = (char *)objp + obj_offset(cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454 printk(KERN_ERR "Next obj: start=%p, len=%d\n",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001455 realobj, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001456 print_objinfo(cachep, objp, 2);
1457 }
1458 }
1459}
1460#endif
1461
1462/* Destroy all the objs in a slab, and release the mem back to the system.
1463 * Before calling the slab must have been unlinked from the cache.
1464 * The cache-lock is not held/needed.
1465 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001466static void slab_destroy(kmem_cache_t *cachep, struct slab *slabp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001467{
1468 void *addr = slabp->s_mem - slabp->colouroff;
1469
1470#if DEBUG
1471 int i;
1472 for (i = 0; i < cachep->num; i++) {
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001473 void *objp = slabp->s_mem + cachep->buffer_size * i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001474
1475 if (cachep->flags & SLAB_POISON) {
1476#ifdef CONFIG_DEBUG_PAGEALLOC
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001477 if ((cachep->buffer_size % PAGE_SIZE) == 0
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001478 && OFF_SLAB(cachep))
1479 kernel_map_pages(virt_to_page(objp),
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001480 cachep->buffer_size / PAGE_SIZE,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001481 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001482 else
1483 check_poison_obj(cachep, objp);
1484#else
1485 check_poison_obj(cachep, objp);
1486#endif
1487 }
1488 if (cachep->flags & SLAB_RED_ZONE) {
1489 if (*dbg_redzone1(cachep, objp) != RED_INACTIVE)
1490 slab_error(cachep, "start of a freed object "
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001491 "was overwritten");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001492 if (*dbg_redzone2(cachep, objp) != RED_INACTIVE)
1493 slab_error(cachep, "end of a freed object "
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001494 "was overwritten");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001495 }
1496 if (cachep->dtor && !(cachep->flags & SLAB_POISON))
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001497 (cachep->dtor) (objp + obj_offset(cachep), cachep, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001498 }
1499#else
1500 if (cachep->dtor) {
1501 int i;
1502 for (i = 0; i < cachep->num; i++) {
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001503 void *objp = slabp->s_mem + cachep->buffer_size * i;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001504 (cachep->dtor) (objp, cachep, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001505 }
1506 }
1507#endif
1508
1509 if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) {
1510 struct slab_rcu *slab_rcu;
1511
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001512 slab_rcu = (struct slab_rcu *)slabp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001513 slab_rcu->cachep = cachep;
1514 slab_rcu->addr = addr;
1515 call_rcu(&slab_rcu->head, kmem_rcu_free);
1516 } else {
1517 kmem_freepages(cachep, addr);
1518 if (OFF_SLAB(cachep))
1519 kmem_cache_free(cachep->slabp_cache, slabp);
1520 }
1521}
1522
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001523/* For setting up all the kmem_list3s for cache whose buffer_size is same
Christoph Lametere498be72005-09-09 13:03:32 -07001524 as size of kmem_list3. */
1525static inline void set_up_list3s(kmem_cache_t *cachep, int index)
1526{
1527 int node;
1528
1529 for_each_online_node(node) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001530 cachep->nodelists[node] = &initkmem_list3[index + node];
Christoph Lametere498be72005-09-09 13:03:32 -07001531 cachep->nodelists[node]->next_reap = jiffies +
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001532 REAPTIMEOUT_LIST3 +
1533 ((unsigned long)cachep) % REAPTIMEOUT_LIST3;
Christoph Lametere498be72005-09-09 13:03:32 -07001534 }
1535}
1536
Linus Torvalds1da177e2005-04-16 15:20:36 -07001537/**
Pekka Enberg4d268eb2006-01-08 01:00:36 -08001538 * calculate_slab_order - calculate size (page order) of slabs and the number
1539 * of objects per slab.
1540 *
1541 * This could be made much more intelligent. For now, try to avoid using
1542 * high order pages for slabs. When the gfp() functions are more friendly
1543 * towards high-order requests, this should be changed.
1544 */
1545static inline size_t calculate_slab_order(kmem_cache_t *cachep, size_t size,
1546 size_t align, gfp_t flags)
1547{
1548 size_t left_over = 0;
1549
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001550 for (;; cachep->gfporder++) {
Pekka Enberg4d268eb2006-01-08 01:00:36 -08001551 unsigned int num;
1552 size_t remainder;
1553
1554 if (cachep->gfporder > MAX_GFP_ORDER) {
1555 cachep->num = 0;
1556 break;
1557 }
1558
1559 cache_estimate(cachep->gfporder, size, align, flags,
1560 &remainder, &num);
1561 if (!num)
1562 continue;
1563 /* More than offslab_limit objects will cause problems */
1564 if (flags & CFLGS_OFF_SLAB && cachep->num > offslab_limit)
1565 break;
1566
1567 cachep->num = num;
1568 left_over = remainder;
1569
1570 /*
1571 * Large number of objects is good, but very large slabs are
1572 * currently bad for the gfp()s.
1573 */
1574 if (cachep->gfporder >= slab_break_gfp_order)
1575 break;
1576
1577 if ((left_over * 8) <= (PAGE_SIZE << cachep->gfporder))
1578 /* Acceptable internal fragmentation */
1579 break;
1580 }
1581 return left_over;
1582}
1583
1584/**
Linus Torvalds1da177e2005-04-16 15:20:36 -07001585 * kmem_cache_create - Create a cache.
1586 * @name: A string which is used in /proc/slabinfo to identify this cache.
1587 * @size: The size of objects to be created in this cache.
1588 * @align: The required alignment for the objects.
1589 * @flags: SLAB flags
1590 * @ctor: A constructor for the objects.
1591 * @dtor: A destructor for the objects.
1592 *
1593 * Returns a ptr to the cache on success, NULL on failure.
1594 * Cannot be called within a int, but can be interrupted.
1595 * The @ctor is run when new pages are allocated by the cache
1596 * and the @dtor is run before the pages are handed back.
1597 *
1598 * @name must be valid until the cache is destroyed. This implies that
1599 * the module calling this has to destroy the cache before getting
1600 * unloaded.
1601 *
1602 * The flags are
1603 *
1604 * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5)
1605 * to catch references to uninitialised memory.
1606 *
1607 * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check
1608 * for buffer overruns.
1609 *
1610 * %SLAB_NO_REAP - Don't automatically reap this cache when we're under
1611 * memory pressure.
1612 *
1613 * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware
1614 * cacheline. This can be beneficial if you're counting cycles as closely
1615 * as davem.
1616 */
1617kmem_cache_t *
1618kmem_cache_create (const char *name, size_t size, size_t align,
1619 unsigned long flags, void (*ctor)(void*, kmem_cache_t *, unsigned long),
1620 void (*dtor)(void*, kmem_cache_t *, unsigned long))
1621{
1622 size_t left_over, slab_size, ralign;
1623 kmem_cache_t *cachep = NULL;
Andrew Morton4f12bb42005-11-07 00:58:00 -08001624 struct list_head *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001625
1626 /*
1627 * Sanity checks... these are all serious usage bugs.
1628 */
1629 if ((!name) ||
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001630 in_interrupt() ||
1631 (size < BYTES_PER_WORD) ||
1632 (size > (1 << MAX_OBJ_ORDER) * PAGE_SIZE) || (dtor && !ctor)) {
1633 printk(KERN_ERR "%s: Early error in slab %s\n",
1634 __FUNCTION__, name);
1635 BUG();
1636 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001637
Ingo Molnarfc0abb12006-01-18 17:42:33 -08001638 mutex_lock(&cache_chain_mutex);
Andrew Morton4f12bb42005-11-07 00:58:00 -08001639
1640 list_for_each(p, &cache_chain) {
1641 kmem_cache_t *pc = list_entry(p, kmem_cache_t, next);
1642 mm_segment_t old_fs = get_fs();
1643 char tmp;
1644 int res;
1645
1646 /*
1647 * This happens when the module gets unloaded and doesn't
1648 * destroy its slab cache and no-one else reuses the vmalloc
1649 * area of the module. Print a warning.
1650 */
1651 set_fs(KERNEL_DS);
1652 res = __get_user(tmp, pc->name);
1653 set_fs(old_fs);
1654 if (res) {
1655 printk("SLAB: cache with size %d has lost its name\n",
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001656 pc->buffer_size);
Andrew Morton4f12bb42005-11-07 00:58:00 -08001657 continue;
1658 }
1659
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001660 if (!strcmp(pc->name, name)) {
Andrew Morton4f12bb42005-11-07 00:58:00 -08001661 printk("kmem_cache_create: duplicate cache %s\n", name);
1662 dump_stack();
1663 goto oops;
1664 }
1665 }
1666
Linus Torvalds1da177e2005-04-16 15:20:36 -07001667#if DEBUG
1668 WARN_ON(strchr(name, ' ')); /* It confuses parsers */
1669 if ((flags & SLAB_DEBUG_INITIAL) && !ctor) {
1670 /* No constructor, but inital state check requested */
1671 printk(KERN_ERR "%s: No con, but init state check "
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001672 "requested - %s\n", __FUNCTION__, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001673 flags &= ~SLAB_DEBUG_INITIAL;
1674 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001675#if FORCED_DEBUG
1676 /*
1677 * Enable redzoning and last user accounting, except for caches with
1678 * large objects, if the increased size would increase the object size
1679 * above the next power of two: caches with object sizes just above a
1680 * power of two have a significant amount of internal fragmentation.
1681 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001682 if ((size < 4096
1683 || fls(size - 1) == fls(size - 1 + 3 * BYTES_PER_WORD)))
1684 flags |= SLAB_RED_ZONE | SLAB_STORE_USER;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685 if (!(flags & SLAB_DESTROY_BY_RCU))
1686 flags |= SLAB_POISON;
1687#endif
1688 if (flags & SLAB_DESTROY_BY_RCU)
1689 BUG_ON(flags & SLAB_POISON);
1690#endif
1691 if (flags & SLAB_DESTROY_BY_RCU)
1692 BUG_ON(dtor);
1693
1694 /*
1695 * Always checks flags, a caller might be expecting debug
1696 * support which isn't available.
1697 */
1698 if (flags & ~CREATE_MASK)
1699 BUG();
1700
1701 /* Check that size is in terms of words. This is needed to avoid
1702 * unaligned accesses for some archs when redzoning is used, and makes
1703 * sure any on-slab bufctl's are also correctly aligned.
1704 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001705 if (size & (BYTES_PER_WORD - 1)) {
1706 size += (BYTES_PER_WORD - 1);
1707 size &= ~(BYTES_PER_WORD - 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001708 }
1709
1710 /* calculate out the final buffer alignment: */
1711 /* 1) arch recommendation: can be overridden for debug */
1712 if (flags & SLAB_HWCACHE_ALIGN) {
1713 /* Default alignment: as specified by the arch code.
1714 * Except if an object is really small, then squeeze multiple
1715 * objects into one cacheline.
1716 */
1717 ralign = cache_line_size();
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001718 while (size <= ralign / 2)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001719 ralign /= 2;
1720 } else {
1721 ralign = BYTES_PER_WORD;
1722 }
1723 /* 2) arch mandated alignment: disables debug if necessary */
1724 if (ralign < ARCH_SLAB_MINALIGN) {
1725 ralign = ARCH_SLAB_MINALIGN;
1726 if (ralign > BYTES_PER_WORD)
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001727 flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001728 }
1729 /* 3) caller mandated alignment: disables debug if necessary */
1730 if (ralign < align) {
1731 ralign = align;
1732 if (ralign > BYTES_PER_WORD)
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001733 flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001734 }
1735 /* 4) Store it. Note that the debug code below can reduce
1736 * the alignment to BYTES_PER_WORD.
1737 */
1738 align = ralign;
1739
1740 /* Get cache's description obj. */
1741 cachep = (kmem_cache_t *) kmem_cache_alloc(&cache_cache, SLAB_KERNEL);
1742 if (!cachep)
Andrew Morton4f12bb42005-11-07 00:58:00 -08001743 goto oops;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001744 memset(cachep, 0, sizeof(kmem_cache_t));
1745
1746#if DEBUG
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001747 cachep->obj_size = size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001748
1749 if (flags & SLAB_RED_ZONE) {
1750 /* redzoning only works with word aligned caches */
1751 align = BYTES_PER_WORD;
1752
1753 /* add space for red zone words */
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001754 cachep->obj_offset += BYTES_PER_WORD;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001755 size += 2 * BYTES_PER_WORD;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001756 }
1757 if (flags & SLAB_STORE_USER) {
1758 /* user store requires word alignment and
1759 * one word storage behind the end of the real
1760 * object.
1761 */
1762 align = BYTES_PER_WORD;
1763 size += BYTES_PER_WORD;
1764 }
1765#if FORCED_DEBUG && defined(CONFIG_DEBUG_PAGEALLOC)
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001766 if (size >= malloc_sizes[INDEX_L3 + 1].cs_size
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001767 && cachep->obj_size > cache_line_size() && size < PAGE_SIZE) {
1768 cachep->obj_offset += PAGE_SIZE - size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001769 size = PAGE_SIZE;
1770 }
1771#endif
1772#endif
1773
1774 /* Determine if the slab management is 'on' or 'off' slab. */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001775 if (size >= (PAGE_SIZE >> 3))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001776 /*
1777 * Size is large, assume best to place the slab management obj
1778 * off-slab (should allow better packing of objs).
1779 */
1780 flags |= CFLGS_OFF_SLAB;
1781
1782 size = ALIGN(size, align);
1783
1784 if ((flags & SLAB_RECLAIM_ACCOUNT) && size <= PAGE_SIZE) {
1785 /*
1786 * A VFS-reclaimable slab tends to have most allocations
1787 * as GFP_NOFS and we really don't want to have to be allocating
1788 * higher-order pages when we are unable to shrink dcache.
1789 */
1790 cachep->gfporder = 0;
1791 cache_estimate(cachep->gfporder, size, align, flags,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001792 &left_over, &cachep->num);
Pekka Enberg4d268eb2006-01-08 01:00:36 -08001793 } else
1794 left_over = calculate_slab_order(cachep, size, align, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001795
1796 if (!cachep->num) {
1797 printk("kmem_cache_create: couldn't create cache %s.\n", name);
1798 kmem_cache_free(&cache_cache, cachep);
1799 cachep = NULL;
Andrew Morton4f12bb42005-11-07 00:58:00 -08001800 goto oops;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001801 }
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001802 slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t)
1803 + sizeof(struct slab), align);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001804
1805 /*
1806 * If the slab has been placed off-slab, and we have enough space then
1807 * move it on-slab. This is at the expense of any extra colouring.
1808 */
1809 if (flags & CFLGS_OFF_SLAB && left_over >= slab_size) {
1810 flags &= ~CFLGS_OFF_SLAB;
1811 left_over -= slab_size;
1812 }
1813
1814 if (flags & CFLGS_OFF_SLAB) {
1815 /* really off slab. No need for manual alignment */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001816 slab_size =
1817 cachep->num * sizeof(kmem_bufctl_t) + sizeof(struct slab);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001818 }
1819
1820 cachep->colour_off = cache_line_size();
1821 /* Offset must be a multiple of the alignment. */
1822 if (cachep->colour_off < align)
1823 cachep->colour_off = align;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001824 cachep->colour = left_over / cachep->colour_off;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001825 cachep->slab_size = slab_size;
1826 cachep->flags = flags;
1827 cachep->gfpflags = 0;
1828 if (flags & SLAB_CACHE_DMA)
1829 cachep->gfpflags |= GFP_DMA;
1830 spin_lock_init(&cachep->spinlock);
Manfred Spraul3dafccf2006-02-01 03:05:42 -08001831 cachep->buffer_size = size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001832
1833 if (flags & CFLGS_OFF_SLAB)
Victor Fuscob2d55072005-09-10 00:26:36 -07001834 cachep->slabp_cache = kmem_find_general_cachep(slab_size, 0u);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001835 cachep->ctor = ctor;
1836 cachep->dtor = dtor;
1837 cachep->name = name;
1838
1839 /* Don't let CPUs to come and go */
1840 lock_cpu_hotplug();
1841
1842 if (g_cpucache_up == FULL) {
1843 enable_cpucache(cachep);
1844 } else {
1845 if (g_cpucache_up == NONE) {
1846 /* Note: the first kmem_cache_create must create
1847 * the cache that's used by kmalloc(24), otherwise
1848 * the creation of further caches will BUG().
1849 */
Christoph Lametere498be72005-09-09 13:03:32 -07001850 cachep->array[smp_processor_id()] =
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001851 &initarray_generic.cache;
Christoph Lametere498be72005-09-09 13:03:32 -07001852
1853 /* If the cache that's used by
1854 * kmalloc(sizeof(kmem_list3)) is the first cache,
1855 * then we need to set up all its list3s, otherwise
1856 * the creation of further caches will BUG().
1857 */
1858 set_up_list3s(cachep, SIZE_AC);
1859 if (INDEX_AC == INDEX_L3)
1860 g_cpucache_up = PARTIAL_L3;
1861 else
1862 g_cpucache_up = PARTIAL_AC;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001863 } else {
Christoph Lametere498be72005-09-09 13:03:32 -07001864 cachep->array[smp_processor_id()] =
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001865 kmalloc(sizeof(struct arraycache_init), GFP_KERNEL);
Christoph Lametere498be72005-09-09 13:03:32 -07001866
1867 if (g_cpucache_up == PARTIAL_AC) {
1868 set_up_list3s(cachep, SIZE_L3);
1869 g_cpucache_up = PARTIAL_L3;
1870 } else {
1871 int node;
1872 for_each_online_node(node) {
1873
1874 cachep->nodelists[node] =
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001875 kmalloc_node(sizeof
1876 (struct kmem_list3),
1877 GFP_KERNEL, node);
Christoph Lametere498be72005-09-09 13:03:32 -07001878 BUG_ON(!cachep->nodelists[node]);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001879 kmem_list3_init(cachep->
1880 nodelists[node]);
Christoph Lametere498be72005-09-09 13:03:32 -07001881 }
1882 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001883 }
Christoph Lametere498be72005-09-09 13:03:32 -07001884 cachep->nodelists[numa_node_id()]->next_reap =
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001885 jiffies + REAPTIMEOUT_LIST3 +
1886 ((unsigned long)cachep) % REAPTIMEOUT_LIST3;
Christoph Lametere498be72005-09-09 13:03:32 -07001887
Linus Torvalds1da177e2005-04-16 15:20:36 -07001888 BUG_ON(!ac_data(cachep));
1889 ac_data(cachep)->avail = 0;
1890 ac_data(cachep)->limit = BOOT_CPUCACHE_ENTRIES;
1891 ac_data(cachep)->batchcount = 1;
1892 ac_data(cachep)->touched = 0;
1893 cachep->batchcount = 1;
1894 cachep->limit = BOOT_CPUCACHE_ENTRIES;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001895 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001896
Linus Torvalds1da177e2005-04-16 15:20:36 -07001897 /* cache setup completed, link it into the list */
1898 list_add(&cachep->next, &cache_chain);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001899 unlock_cpu_hotplug();
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001900 oops:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001901 if (!cachep && (flags & SLAB_PANIC))
1902 panic("kmem_cache_create(): failed to create slab `%s'\n",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001903 name);
Ingo Molnarfc0abb12006-01-18 17:42:33 -08001904 mutex_unlock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001905 return cachep;
1906}
1907EXPORT_SYMBOL(kmem_cache_create);
1908
1909#if DEBUG
1910static void check_irq_off(void)
1911{
1912 BUG_ON(!irqs_disabled());
1913}
1914
1915static void check_irq_on(void)
1916{
1917 BUG_ON(irqs_disabled());
1918}
1919
1920static void check_spinlock_acquired(kmem_cache_t *cachep)
1921{
1922#ifdef CONFIG_SMP
1923 check_irq_off();
Christoph Lametere498be72005-09-09 13:03:32 -07001924 assert_spin_locked(&cachep->nodelists[numa_node_id()]->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001925#endif
1926}
Christoph Lametere498be72005-09-09 13:03:32 -07001927
1928static inline void check_spinlock_acquired_node(kmem_cache_t *cachep, int node)
1929{
1930#ifdef CONFIG_SMP
1931 check_irq_off();
1932 assert_spin_locked(&cachep->nodelists[node]->list_lock);
1933#endif
1934}
1935
Linus Torvalds1da177e2005-04-16 15:20:36 -07001936#else
1937#define check_irq_off() do { } while(0)
1938#define check_irq_on() do { } while(0)
1939#define check_spinlock_acquired(x) do { } while(0)
Christoph Lametere498be72005-09-09 13:03:32 -07001940#define check_spinlock_acquired_node(x, y) do { } while(0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001941#endif
1942
1943/*
1944 * Waits for all CPUs to execute func().
1945 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001946static void smp_call_function_all_cpus(void (*func)(void *arg), void *arg)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001947{
1948 check_irq_on();
1949 preempt_disable();
1950
1951 local_irq_disable();
1952 func(arg);
1953 local_irq_enable();
1954
1955 if (smp_call_function(func, arg, 1, 1))
1956 BUG();
1957
1958 preempt_enable();
1959}
1960
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001961static void drain_array_locked(kmem_cache_t *cachep, struct array_cache *ac,
1962 int force, int node);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001963
1964static void do_drain(void *arg)
1965{
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001966 kmem_cache_t *cachep = (kmem_cache_t *) arg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001967 struct array_cache *ac;
Christoph Lameterff694162005-09-22 21:44:02 -07001968 int node = numa_node_id();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001969
1970 check_irq_off();
1971 ac = ac_data(cachep);
Christoph Lameterff694162005-09-22 21:44:02 -07001972 spin_lock(&cachep->nodelists[node]->list_lock);
1973 free_block(cachep, ac->entry, ac->avail, node);
1974 spin_unlock(&cachep->nodelists[node]->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001975 ac->avail = 0;
1976}
1977
1978static void drain_cpu_caches(kmem_cache_t *cachep)
1979{
Christoph Lametere498be72005-09-09 13:03:32 -07001980 struct kmem_list3 *l3;
1981 int node;
1982
Linus Torvalds1da177e2005-04-16 15:20:36 -07001983 smp_call_function_all_cpus(do_drain, cachep);
1984 check_irq_on();
1985 spin_lock_irq(&cachep->spinlock);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08001986 for_each_online_node(node) {
Christoph Lametere498be72005-09-09 13:03:32 -07001987 l3 = cachep->nodelists[node];
1988 if (l3) {
1989 spin_lock(&l3->list_lock);
1990 drain_array_locked(cachep, l3->shared, 1, node);
1991 spin_unlock(&l3->list_lock);
1992 if (l3->alien)
1993 drain_alien_cache(cachep, l3);
1994 }
1995 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001996 spin_unlock_irq(&cachep->spinlock);
1997}
1998
Christoph Lametere498be72005-09-09 13:03:32 -07001999static int __node_shrink(kmem_cache_t *cachep, int node)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002000{
2001 struct slab *slabp;
Christoph Lametere498be72005-09-09 13:03:32 -07002002 struct kmem_list3 *l3 = cachep->nodelists[node];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002003 int ret;
2004
Christoph Lametere498be72005-09-09 13:03:32 -07002005 for (;;) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002006 struct list_head *p;
2007
Christoph Lametere498be72005-09-09 13:03:32 -07002008 p = l3->slabs_free.prev;
2009 if (p == &l3->slabs_free)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002010 break;
2011
Christoph Lametere498be72005-09-09 13:03:32 -07002012 slabp = list_entry(l3->slabs_free.prev, struct slab, list);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002013#if DEBUG
2014 if (slabp->inuse)
2015 BUG();
2016#endif
2017 list_del(&slabp->list);
2018
Christoph Lametere498be72005-09-09 13:03:32 -07002019 l3->free_objects -= cachep->num;
2020 spin_unlock_irq(&l3->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002021 slab_destroy(cachep, slabp);
Christoph Lametere498be72005-09-09 13:03:32 -07002022 spin_lock_irq(&l3->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002023 }
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002024 ret = !list_empty(&l3->slabs_full) || !list_empty(&l3->slabs_partial);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002025 return ret;
2026}
2027
Christoph Lametere498be72005-09-09 13:03:32 -07002028static int __cache_shrink(kmem_cache_t *cachep)
2029{
2030 int ret = 0, i = 0;
2031 struct kmem_list3 *l3;
2032
2033 drain_cpu_caches(cachep);
2034
2035 check_irq_on();
2036 for_each_online_node(i) {
2037 l3 = cachep->nodelists[i];
2038 if (l3) {
2039 spin_lock_irq(&l3->list_lock);
2040 ret += __node_shrink(cachep, i);
2041 spin_unlock_irq(&l3->list_lock);
2042 }
2043 }
2044 return (ret ? 1 : 0);
2045}
2046
Linus Torvalds1da177e2005-04-16 15:20:36 -07002047/**
2048 * kmem_cache_shrink - Shrink a cache.
2049 * @cachep: The cache to shrink.
2050 *
2051 * Releases as many slabs as possible for a cache.
2052 * To help debugging, a zero exit status indicates all slabs were released.
2053 */
2054int kmem_cache_shrink(kmem_cache_t *cachep)
2055{
2056 if (!cachep || in_interrupt())
2057 BUG();
2058
2059 return __cache_shrink(cachep);
2060}
2061EXPORT_SYMBOL(kmem_cache_shrink);
2062
2063/**
2064 * kmem_cache_destroy - delete a cache
2065 * @cachep: the cache to destroy
2066 *
2067 * Remove a kmem_cache_t object from the slab cache.
2068 * Returns 0 on success.
2069 *
2070 * It is expected this function will be called by a module when it is
2071 * unloaded. This will remove the cache completely, and avoid a duplicate
2072 * cache being allocated each time a module is loaded and unloaded, if the
2073 * module doesn't have persistent in-kernel storage across loads and unloads.
2074 *
2075 * The cache must be empty before calling this function.
2076 *
2077 * The caller must guarantee that noone will allocate memory from the cache
2078 * during the kmem_cache_destroy().
2079 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002080int kmem_cache_destroy(kmem_cache_t *cachep)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002081{
2082 int i;
Christoph Lametere498be72005-09-09 13:03:32 -07002083 struct kmem_list3 *l3;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002084
2085 if (!cachep || in_interrupt())
2086 BUG();
2087
2088 /* Don't let CPUs to come and go */
2089 lock_cpu_hotplug();
2090
2091 /* Find the cache in the chain of caches. */
Ingo Molnarfc0abb12006-01-18 17:42:33 -08002092 mutex_lock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002093 /*
2094 * the chain is never empty, cache_cache is never destroyed
2095 */
2096 list_del(&cachep->next);
Ingo Molnarfc0abb12006-01-18 17:42:33 -08002097 mutex_unlock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002098
2099 if (__cache_shrink(cachep)) {
2100 slab_error(cachep, "Can't free all objects");
Ingo Molnarfc0abb12006-01-18 17:42:33 -08002101 mutex_lock(&cache_chain_mutex);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002102 list_add(&cachep->next, &cache_chain);
Ingo Molnarfc0abb12006-01-18 17:42:33 -08002103 mutex_unlock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002104 unlock_cpu_hotplug();
2105 return 1;
2106 }
2107
2108 if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU))
Paul E. McKenneyfbd568a3e2005-05-01 08:59:04 -07002109 synchronize_rcu();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002110
Christoph Lametere498be72005-09-09 13:03:32 -07002111 for_each_online_cpu(i)
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002112 kfree(cachep->array[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002113
2114 /* NUMA: free the list3 structures */
Christoph Lametere498be72005-09-09 13:03:32 -07002115 for_each_online_node(i) {
2116 if ((l3 = cachep->nodelists[i])) {
2117 kfree(l3->shared);
2118 free_alien_cache(l3->alien);
2119 kfree(l3);
2120 }
2121 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002122 kmem_cache_free(&cache_cache, cachep);
2123
2124 unlock_cpu_hotplug();
2125
2126 return 0;
2127}
2128EXPORT_SYMBOL(kmem_cache_destroy);
2129
2130/* Get the memory for a slab management obj. */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002131static struct slab *alloc_slabmgmt(kmem_cache_t *cachep, void *objp,
2132 int colour_off, gfp_t local_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002133{
2134 struct slab *slabp;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002135
Linus Torvalds1da177e2005-04-16 15:20:36 -07002136 if (OFF_SLAB(cachep)) {
2137 /* Slab management obj is off-slab. */
2138 slabp = kmem_cache_alloc(cachep->slabp_cache, local_flags);
2139 if (!slabp)
2140 return NULL;
2141 } else {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002142 slabp = objp + colour_off;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002143 colour_off += cachep->slab_size;
2144 }
2145 slabp->inuse = 0;
2146 slabp->colouroff = colour_off;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002147 slabp->s_mem = objp + colour_off;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002148
2149 return slabp;
2150}
2151
2152static inline kmem_bufctl_t *slab_bufctl(struct slab *slabp)
2153{
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002154 return (kmem_bufctl_t *) (slabp + 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002155}
2156
2157static void cache_init_objs(kmem_cache_t *cachep,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002158 struct slab *slabp, unsigned long ctor_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002159{
2160 int i;
2161
2162 for (i = 0; i < cachep->num; i++) {
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002163 void *objp = slabp->s_mem + cachep->buffer_size * i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002164#if DEBUG
2165 /* need to poison the objs? */
2166 if (cachep->flags & SLAB_POISON)
2167 poison_obj(cachep, objp, POISON_FREE);
2168 if (cachep->flags & SLAB_STORE_USER)
2169 *dbg_userword(cachep, objp) = NULL;
2170
2171 if (cachep->flags & SLAB_RED_ZONE) {
2172 *dbg_redzone1(cachep, objp) = RED_INACTIVE;
2173 *dbg_redzone2(cachep, objp) = RED_INACTIVE;
2174 }
2175 /*
2176 * Constructors are not allowed to allocate memory from
2177 * the same cache which they are a constructor for.
2178 * Otherwise, deadlock. They must also be threaded.
2179 */
2180 if (cachep->ctor && !(cachep->flags & SLAB_POISON))
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002181 cachep->ctor(objp + obj_offset(cachep), cachep,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002182 ctor_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002183
2184 if (cachep->flags & SLAB_RED_ZONE) {
2185 if (*dbg_redzone2(cachep, objp) != RED_INACTIVE)
2186 slab_error(cachep, "constructor overwrote the"
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002187 " end of an object");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002188 if (*dbg_redzone1(cachep, objp) != RED_INACTIVE)
2189 slab_error(cachep, "constructor overwrote the"
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002190 " start of an object");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002191 }
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002192 if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep)
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002193 && cachep->flags & SLAB_POISON)
2194 kernel_map_pages(virt_to_page(objp),
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002195 cachep->buffer_size / PAGE_SIZE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002196#else
2197 if (cachep->ctor)
2198 cachep->ctor(objp, cachep, ctor_flags);
2199#endif
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002200 slab_bufctl(slabp)[i] = i + 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002201 }
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002202 slab_bufctl(slabp)[i - 1] = BUFCTL_END;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002203 slabp->free = 0;
2204}
2205
Al Viro6daa0e22005-10-21 03:18:50 -04002206static void kmem_flagcheck(kmem_cache_t *cachep, gfp_t flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002207{
2208 if (flags & SLAB_DMA) {
2209 if (!(cachep->gfpflags & GFP_DMA))
2210 BUG();
2211 } else {
2212 if (cachep->gfpflags & GFP_DMA)
2213 BUG();
2214 }
2215}
2216
2217static void set_slab_attr(kmem_cache_t *cachep, struct slab *slabp, void *objp)
2218{
2219 int i;
2220 struct page *page;
2221
2222 /* Nasty!!!!!! I hope this is OK. */
2223 i = 1 << cachep->gfporder;
2224 page = virt_to_page(objp);
2225 do {
Pekka Enberg065d41c2005-11-13 16:06:46 -08002226 page_set_cache(page, cachep);
2227 page_set_slab(page, slabp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002228 page++;
2229 } while (--i);
2230}
2231
2232/*
2233 * Grow (by 1) the number of slabs within a cache. This is called by
2234 * kmem_cache_alloc() when there are no active objs left in a cache.
2235 */
Al Virodd0fc662005-10-07 07:46:04 +01002236static int cache_grow(kmem_cache_t *cachep, gfp_t flags, int nodeid)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002237{
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002238 struct slab *slabp;
2239 void *objp;
2240 size_t offset;
2241 gfp_t local_flags;
2242 unsigned long ctor_flags;
Christoph Lametere498be72005-09-09 13:03:32 -07002243 struct kmem_list3 *l3;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002244
2245 /* Be lazy and only check for valid flags here,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002246 * keeping it out of the critical path in kmem_cache_alloc().
Linus Torvalds1da177e2005-04-16 15:20:36 -07002247 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002248 if (flags & ~(SLAB_DMA | SLAB_LEVEL_MASK | SLAB_NO_GROW))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002249 BUG();
2250 if (flags & SLAB_NO_GROW)
2251 return 0;
2252
2253 ctor_flags = SLAB_CTOR_CONSTRUCTOR;
2254 local_flags = (flags & SLAB_LEVEL_MASK);
2255 if (!(local_flags & __GFP_WAIT))
2256 /*
2257 * Not allowed to sleep. Need to tell a constructor about
2258 * this - it might need to know...
2259 */
2260 ctor_flags |= SLAB_CTOR_ATOMIC;
2261
2262 /* About to mess with non-constant members - lock. */
2263 check_irq_off();
2264 spin_lock(&cachep->spinlock);
2265
2266 /* Get colour for the slab, and cal the next value. */
2267 offset = cachep->colour_next;
2268 cachep->colour_next++;
2269 if (cachep->colour_next >= cachep->colour)
2270 cachep->colour_next = 0;
2271 offset *= cachep->colour_off;
2272
2273 spin_unlock(&cachep->spinlock);
2274
Christoph Lametere498be72005-09-09 13:03:32 -07002275 check_irq_off();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002276 if (local_flags & __GFP_WAIT)
2277 local_irq_enable();
2278
2279 /*
2280 * The test for missing atomic flag is performed here, rather than
2281 * the more obvious place, simply to reduce the critical path length
2282 * in kmem_cache_alloc(). If a caller is seriously mis-behaving they
2283 * will eventually be caught here (where it matters).
2284 */
2285 kmem_flagcheck(cachep, flags);
2286
Christoph Lametere498be72005-09-09 13:03:32 -07002287 /* Get mem for the objs.
2288 * Attempt to allocate a physical page from 'nodeid',
2289 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002290 if (!(objp = kmem_getpages(cachep, flags, nodeid)))
2291 goto failed;
2292
2293 /* Get slab management. */
2294 if (!(slabp = alloc_slabmgmt(cachep, objp, offset, local_flags)))
2295 goto opps1;
2296
Christoph Lametere498be72005-09-09 13:03:32 -07002297 slabp->nodeid = nodeid;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002298 set_slab_attr(cachep, slabp, objp);
2299
2300 cache_init_objs(cachep, slabp, ctor_flags);
2301
2302 if (local_flags & __GFP_WAIT)
2303 local_irq_disable();
2304 check_irq_off();
Christoph Lametere498be72005-09-09 13:03:32 -07002305 l3 = cachep->nodelists[nodeid];
2306 spin_lock(&l3->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002307
2308 /* Make slab active. */
Christoph Lametere498be72005-09-09 13:03:32 -07002309 list_add_tail(&slabp->list, &(l3->slabs_free));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002310 STATS_INC_GROWN(cachep);
Christoph Lametere498be72005-09-09 13:03:32 -07002311 l3->free_objects += cachep->num;
2312 spin_unlock(&l3->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002313 return 1;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002314 opps1:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002315 kmem_freepages(cachep, objp);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002316 failed:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002317 if (local_flags & __GFP_WAIT)
2318 local_irq_disable();
2319 return 0;
2320}
2321
2322#if DEBUG
2323
2324/*
2325 * Perform extra freeing checks:
2326 * - detect bad pointers.
2327 * - POISON/RED_ZONE checking
2328 * - destructor calls, for caches with POISON+dtor
2329 */
2330static void kfree_debugcheck(const void *objp)
2331{
2332 struct page *page;
2333
2334 if (!virt_addr_valid(objp)) {
2335 printk(KERN_ERR "kfree_debugcheck: out of range ptr %lxh.\n",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002336 (unsigned long)objp);
2337 BUG();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002338 }
2339 page = virt_to_page(objp);
2340 if (!PageSlab(page)) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002341 printk(KERN_ERR "kfree_debugcheck: bad ptr %lxh.\n",
2342 (unsigned long)objp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002343 BUG();
2344 }
2345}
2346
2347static void *cache_free_debugcheck(kmem_cache_t *cachep, void *objp,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002348 void *caller)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002349{
2350 struct page *page;
2351 unsigned int objnr;
2352 struct slab *slabp;
2353
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002354 objp -= obj_offset(cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002355 kfree_debugcheck(objp);
2356 page = virt_to_page(objp);
2357
Pekka Enberg065d41c2005-11-13 16:06:46 -08002358 if (page_get_cache(page) != cachep) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002359 printk(KERN_ERR
2360 "mismatch in kmem_cache_free: expected cache %p, got %p\n",
2361 page_get_cache(page), cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002362 printk(KERN_ERR "%p is %s.\n", cachep, cachep->name);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002363 printk(KERN_ERR "%p is %s.\n", page_get_cache(page),
2364 page_get_cache(page)->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002365 WARN_ON(1);
2366 }
Pekka Enberg065d41c2005-11-13 16:06:46 -08002367 slabp = page_get_slab(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002368
2369 if (cachep->flags & SLAB_RED_ZONE) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002370 if (*dbg_redzone1(cachep, objp) != RED_ACTIVE
2371 || *dbg_redzone2(cachep, objp) != RED_ACTIVE) {
2372 slab_error(cachep,
2373 "double free, or memory outside"
2374 " object was overwritten");
2375 printk(KERN_ERR
2376 "%p: redzone 1: 0x%lx, redzone 2: 0x%lx.\n",
2377 objp, *dbg_redzone1(cachep, objp),
2378 *dbg_redzone2(cachep, objp));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002379 }
2380 *dbg_redzone1(cachep, objp) = RED_INACTIVE;
2381 *dbg_redzone2(cachep, objp) = RED_INACTIVE;
2382 }
2383 if (cachep->flags & SLAB_STORE_USER)
2384 *dbg_userword(cachep, objp) = caller;
2385
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002386 objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002387
2388 BUG_ON(objnr >= cachep->num);
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002389 BUG_ON(objp != slabp->s_mem + objnr * cachep->buffer_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002390
2391 if (cachep->flags & SLAB_DEBUG_INITIAL) {
2392 /* Need to call the slab's constructor so the
2393 * caller can perform a verify of its state (debugging).
2394 * Called without the cache-lock held.
2395 */
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002396 cachep->ctor(objp + obj_offset(cachep),
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002397 cachep, SLAB_CTOR_CONSTRUCTOR | SLAB_CTOR_VERIFY);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002398 }
2399 if (cachep->flags & SLAB_POISON && cachep->dtor) {
2400 /* we want to cache poison the object,
2401 * call the destruction callback
2402 */
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002403 cachep->dtor(objp + obj_offset(cachep), cachep, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002404 }
2405 if (cachep->flags & SLAB_POISON) {
2406#ifdef CONFIG_DEBUG_PAGEALLOC
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002407 if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002408 store_stackinfo(cachep, objp, (unsigned long)caller);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002409 kernel_map_pages(virt_to_page(objp),
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002410 cachep->buffer_size / PAGE_SIZE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002411 } else {
2412 poison_obj(cachep, objp, POISON_FREE);
2413 }
2414#else
2415 poison_obj(cachep, objp, POISON_FREE);
2416#endif
2417 }
2418 return objp;
2419}
2420
2421static void check_slabp(kmem_cache_t *cachep, struct slab *slabp)
2422{
2423 kmem_bufctl_t i;
2424 int entries = 0;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002425
Linus Torvalds1da177e2005-04-16 15:20:36 -07002426 /* Check slab's freelist to see if this obj is there. */
2427 for (i = slabp->free; i != BUFCTL_END; i = slab_bufctl(slabp)[i]) {
2428 entries++;
2429 if (entries > cachep->num || i >= cachep->num)
2430 goto bad;
2431 }
2432 if (entries != cachep->num - slabp->inuse) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002433 bad:
2434 printk(KERN_ERR
2435 "slab: Internal list corruption detected in cache '%s'(%d), slabp %p(%d). Hexdump:\n",
2436 cachep->name, cachep->num, slabp, slabp->inuse);
2437 for (i = 0;
2438 i < sizeof(slabp) + cachep->num * sizeof(kmem_bufctl_t);
2439 i++) {
2440 if ((i % 16) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002441 printk("\n%03x:", i);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002442 printk(" %02x", ((unsigned char *)slabp)[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002443 }
2444 printk("\n");
2445 BUG();
2446 }
2447}
2448#else
2449#define kfree_debugcheck(x) do { } while(0)
2450#define cache_free_debugcheck(x,objp,z) (objp)
2451#define check_slabp(x,y) do { } while(0)
2452#endif
2453
Al Virodd0fc662005-10-07 07:46:04 +01002454static void *cache_alloc_refill(kmem_cache_t *cachep, gfp_t flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002455{
2456 int batchcount;
2457 struct kmem_list3 *l3;
2458 struct array_cache *ac;
2459
2460 check_irq_off();
2461 ac = ac_data(cachep);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002462 retry:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002463 batchcount = ac->batchcount;
2464 if (!ac->touched && batchcount > BATCHREFILL_LIMIT) {
2465 /* if there was little recent activity on this
2466 * cache, then perform only a partial refill.
2467 * Otherwise we could generate refill bouncing.
2468 */
2469 batchcount = BATCHREFILL_LIMIT;
2470 }
Christoph Lametere498be72005-09-09 13:03:32 -07002471 l3 = cachep->nodelists[numa_node_id()];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002472
Christoph Lametere498be72005-09-09 13:03:32 -07002473 BUG_ON(ac->avail > 0 || !l3);
2474 spin_lock(&l3->list_lock);
2475
Linus Torvalds1da177e2005-04-16 15:20:36 -07002476 if (l3->shared) {
2477 struct array_cache *shared_array = l3->shared;
2478 if (shared_array->avail) {
2479 if (batchcount > shared_array->avail)
2480 batchcount = shared_array->avail;
2481 shared_array->avail -= batchcount;
2482 ac->avail = batchcount;
Christoph Lametere498be72005-09-09 13:03:32 -07002483 memcpy(ac->entry,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002484 &(shared_array->entry[shared_array->avail]),
2485 sizeof(void *) * batchcount);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002486 shared_array->touched = 1;
2487 goto alloc_done;
2488 }
2489 }
2490 while (batchcount > 0) {
2491 struct list_head *entry;
2492 struct slab *slabp;
2493 /* Get slab alloc is to come from. */
2494 entry = l3->slabs_partial.next;
2495 if (entry == &l3->slabs_partial) {
2496 l3->free_touched = 1;
2497 entry = l3->slabs_free.next;
2498 if (entry == &l3->slabs_free)
2499 goto must_grow;
2500 }
2501
2502 slabp = list_entry(entry, struct slab, list);
2503 check_slabp(cachep, slabp);
2504 check_spinlock_acquired(cachep);
2505 while (slabp->inuse < cachep->num && batchcount--) {
2506 kmem_bufctl_t next;
2507 STATS_INC_ALLOCED(cachep);
2508 STATS_INC_ACTIVE(cachep);
2509 STATS_SET_HIGH(cachep);
2510
2511 /* get obj pointer */
Christoph Lametere498be72005-09-09 13:03:32 -07002512 ac->entry[ac->avail++] = slabp->s_mem +
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002513 slabp->free * cachep->buffer_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002514
2515 slabp->inuse++;
2516 next = slab_bufctl(slabp)[slabp->free];
2517#if DEBUG
2518 slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE;
Christoph Lameter09ad4bb2005-10-29 18:15:52 -07002519 WARN_ON(numa_node_id() != slabp->nodeid);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002520#endif
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002521 slabp->free = next;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002522 }
2523 check_slabp(cachep, slabp);
2524
2525 /* move slabp to correct slabp list: */
2526 list_del(&slabp->list);
2527 if (slabp->free == BUFCTL_END)
2528 list_add(&slabp->list, &l3->slabs_full);
2529 else
2530 list_add(&slabp->list, &l3->slabs_partial);
2531 }
2532
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002533 must_grow:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002534 l3->free_objects -= ac->avail;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002535 alloc_done:
Christoph Lametere498be72005-09-09 13:03:32 -07002536 spin_unlock(&l3->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002537
2538 if (unlikely(!ac->avail)) {
2539 int x;
Christoph Lametere498be72005-09-09 13:03:32 -07002540 x = cache_grow(cachep, flags, numa_node_id());
2541
Linus Torvalds1da177e2005-04-16 15:20:36 -07002542 // cache_grow can reenable interrupts, then ac could change.
2543 ac = ac_data(cachep);
2544 if (!x && ac->avail == 0) // no objects in sight? abort
2545 return NULL;
2546
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002547 if (!ac->avail) // objects refilled by interrupt?
Linus Torvalds1da177e2005-04-16 15:20:36 -07002548 goto retry;
2549 }
2550 ac->touched = 1;
Christoph Lametere498be72005-09-09 13:03:32 -07002551 return ac->entry[--ac->avail];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002552}
2553
2554static inline void
Al Virodd0fc662005-10-07 07:46:04 +01002555cache_alloc_debugcheck_before(kmem_cache_t *cachep, gfp_t flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002556{
2557 might_sleep_if(flags & __GFP_WAIT);
2558#if DEBUG
2559 kmem_flagcheck(cachep, flags);
2560#endif
2561}
2562
2563#if DEBUG
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002564static void *cache_alloc_debugcheck_after(kmem_cache_t *cachep, gfp_t flags,
2565 void *objp, void *caller)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002566{
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002567 if (!objp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002568 return objp;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002569 if (cachep->flags & SLAB_POISON) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002570#ifdef CONFIG_DEBUG_PAGEALLOC
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002571 if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep))
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002572 kernel_map_pages(virt_to_page(objp),
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002573 cachep->buffer_size / PAGE_SIZE, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002574 else
2575 check_poison_obj(cachep, objp);
2576#else
2577 check_poison_obj(cachep, objp);
2578#endif
2579 poison_obj(cachep, objp, POISON_INUSE);
2580 }
2581 if (cachep->flags & SLAB_STORE_USER)
2582 *dbg_userword(cachep, objp) = caller;
2583
2584 if (cachep->flags & SLAB_RED_ZONE) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002585 if (*dbg_redzone1(cachep, objp) != RED_INACTIVE
2586 || *dbg_redzone2(cachep, objp) != RED_INACTIVE) {
2587 slab_error(cachep,
2588 "double free, or memory outside"
2589 " object was overwritten");
2590 printk(KERN_ERR
2591 "%p: redzone 1: 0x%lx, redzone 2: 0x%lx.\n",
2592 objp, *dbg_redzone1(cachep, objp),
2593 *dbg_redzone2(cachep, objp));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002594 }
2595 *dbg_redzone1(cachep, objp) = RED_ACTIVE;
2596 *dbg_redzone2(cachep, objp) = RED_ACTIVE;
2597 }
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002598 objp += obj_offset(cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002599 if (cachep->ctor && cachep->flags & SLAB_POISON) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002600 unsigned long ctor_flags = SLAB_CTOR_CONSTRUCTOR;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002601
2602 if (!(flags & __GFP_WAIT))
2603 ctor_flags |= SLAB_CTOR_ATOMIC;
2604
2605 cachep->ctor(objp, cachep, ctor_flags);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002606 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002607 return objp;
2608}
2609#else
2610#define cache_alloc_debugcheck_after(a,b,objp,d) (objp)
2611#endif
2612
Al Virodd0fc662005-10-07 07:46:04 +01002613static inline void *____cache_alloc(kmem_cache_t *cachep, gfp_t flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002614{
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002615 void *objp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002616 struct array_cache *ac;
2617
Christoph Lameterdc85da12006-01-18 17:42:36 -08002618#ifdef CONFIG_NUMA
Christoph Lameter86c562a2006-01-18 17:42:37 -08002619 if (unlikely(current->mempolicy && !in_interrupt())) {
Christoph Lameterdc85da12006-01-18 17:42:36 -08002620 int nid = slab_node(current->mempolicy);
2621
2622 if (nid != numa_node_id())
2623 return __cache_alloc_node(cachep, flags, nid);
2624 }
2625#endif
2626
Alok N Kataria5c382302005-09-27 21:45:46 -07002627 check_irq_off();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002628 ac = ac_data(cachep);
2629 if (likely(ac->avail)) {
2630 STATS_INC_ALLOCHIT(cachep);
2631 ac->touched = 1;
Christoph Lametere498be72005-09-09 13:03:32 -07002632 objp = ac->entry[--ac->avail];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002633 } else {
2634 STATS_INC_ALLOCMISS(cachep);
2635 objp = cache_alloc_refill(cachep, flags);
2636 }
Alok N Kataria5c382302005-09-27 21:45:46 -07002637 return objp;
2638}
2639
Al Virodd0fc662005-10-07 07:46:04 +01002640static inline void *__cache_alloc(kmem_cache_t *cachep, gfp_t flags)
Alok N Kataria5c382302005-09-27 21:45:46 -07002641{
2642 unsigned long save_flags;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002643 void *objp;
Alok N Kataria5c382302005-09-27 21:45:46 -07002644
2645 cache_alloc_debugcheck_before(cachep, flags);
2646
2647 local_irq_save(save_flags);
2648 objp = ____cache_alloc(cachep, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002649 local_irq_restore(save_flags);
Eric Dumazet34342e82005-09-03 15:55:06 -07002650 objp = cache_alloc_debugcheck_after(cachep, flags, objp,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002651 __builtin_return_address(0));
Eric Dumazet34342e82005-09-03 15:55:06 -07002652 prefetchw(objp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002653 return objp;
2654}
2655
Christoph Lametere498be72005-09-09 13:03:32 -07002656#ifdef CONFIG_NUMA
2657/*
2658 * A interface to enable slab creation on nodeid
Linus Torvalds1da177e2005-04-16 15:20:36 -07002659 */
Al Viro6daa0e22005-10-21 03:18:50 -04002660static void *__cache_alloc_node(kmem_cache_t *cachep, gfp_t flags, int nodeid)
Christoph Lametere498be72005-09-09 13:03:32 -07002661{
2662 struct list_head *entry;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002663 struct slab *slabp;
2664 struct kmem_list3 *l3;
2665 void *obj;
2666 kmem_bufctl_t next;
2667 int x;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002668
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002669 l3 = cachep->nodelists[nodeid];
2670 BUG_ON(!l3);
Christoph Lametere498be72005-09-09 13:03:32 -07002671
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002672 retry:
2673 spin_lock(&l3->list_lock);
2674 entry = l3->slabs_partial.next;
2675 if (entry == &l3->slabs_partial) {
2676 l3->free_touched = 1;
2677 entry = l3->slabs_free.next;
2678 if (entry == &l3->slabs_free)
2679 goto must_grow;
2680 }
Christoph Lametere498be72005-09-09 13:03:32 -07002681
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002682 slabp = list_entry(entry, struct slab, list);
2683 check_spinlock_acquired_node(cachep, nodeid);
2684 check_slabp(cachep, slabp);
Christoph Lametere498be72005-09-09 13:03:32 -07002685
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002686 STATS_INC_NODEALLOCS(cachep);
2687 STATS_INC_ACTIVE(cachep);
2688 STATS_SET_HIGH(cachep);
Christoph Lametere498be72005-09-09 13:03:32 -07002689
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002690 BUG_ON(slabp->inuse == cachep->num);
Christoph Lametere498be72005-09-09 13:03:32 -07002691
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002692 /* get obj pointer */
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002693 obj = slabp->s_mem + slabp->free * cachep->buffer_size;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002694 slabp->inuse++;
2695 next = slab_bufctl(slabp)[slabp->free];
Christoph Lametere498be72005-09-09 13:03:32 -07002696#if DEBUG
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002697 slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE;
Christoph Lametere498be72005-09-09 13:03:32 -07002698#endif
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002699 slabp->free = next;
2700 check_slabp(cachep, slabp);
2701 l3->free_objects--;
2702 /* move slabp to correct slabp list: */
2703 list_del(&slabp->list);
Christoph Lametere498be72005-09-09 13:03:32 -07002704
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002705 if (slabp->free == BUFCTL_END) {
2706 list_add(&slabp->list, &l3->slabs_full);
2707 } else {
2708 list_add(&slabp->list, &l3->slabs_partial);
2709 }
Christoph Lametere498be72005-09-09 13:03:32 -07002710
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002711 spin_unlock(&l3->list_lock);
2712 goto done;
Christoph Lametere498be72005-09-09 13:03:32 -07002713
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002714 must_grow:
2715 spin_unlock(&l3->list_lock);
2716 x = cache_grow(cachep, flags, nodeid);
Christoph Lametere498be72005-09-09 13:03:32 -07002717
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002718 if (!x)
2719 return NULL;
Christoph Lametere498be72005-09-09 13:03:32 -07002720
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002721 goto retry;
2722 done:
2723 return obj;
Christoph Lametere498be72005-09-09 13:03:32 -07002724}
2725#endif
2726
2727/*
2728 * Caller needs to acquire correct kmem_list's list_lock
2729 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002730static void free_block(kmem_cache_t *cachep, void **objpp, int nr_objects,
2731 int node)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002732{
2733 int i;
Christoph Lametere498be72005-09-09 13:03:32 -07002734 struct kmem_list3 *l3;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002735
2736 for (i = 0; i < nr_objects; i++) {
2737 void *objp = objpp[i];
2738 struct slab *slabp;
2739 unsigned int objnr;
2740
Pekka Enberg065d41c2005-11-13 16:06:46 -08002741 slabp = page_get_slab(virt_to_page(objp));
Christoph Lameterff694162005-09-22 21:44:02 -07002742 l3 = cachep->nodelists[node];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002743 list_del(&slabp->list);
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002744 objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size;
Christoph Lameterff694162005-09-22 21:44:02 -07002745 check_spinlock_acquired_node(cachep, node);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002746 check_slabp(cachep, slabp);
Christoph Lametere498be72005-09-09 13:03:32 -07002747
Linus Torvalds1da177e2005-04-16 15:20:36 -07002748#if DEBUG
Christoph Lameter09ad4bb2005-10-29 18:15:52 -07002749 /* Verify that the slab belongs to the intended node */
2750 WARN_ON(slabp->nodeid != node);
2751
Linus Torvalds1da177e2005-04-16 15:20:36 -07002752 if (slab_bufctl(slabp)[objnr] != BUFCTL_FREE) {
Christoph Lametere498be72005-09-09 13:03:32 -07002753 printk(KERN_ERR "slab: double free detected in cache "
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002754 "'%s', objp %p\n", cachep->name, objp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002755 BUG();
2756 }
2757#endif
2758 slab_bufctl(slabp)[objnr] = slabp->free;
2759 slabp->free = objnr;
2760 STATS_DEC_ACTIVE(cachep);
2761 slabp->inuse--;
Christoph Lametere498be72005-09-09 13:03:32 -07002762 l3->free_objects++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002763 check_slabp(cachep, slabp);
2764
2765 /* fixup slab chains */
2766 if (slabp->inuse == 0) {
Christoph Lametere498be72005-09-09 13:03:32 -07002767 if (l3->free_objects > l3->free_limit) {
2768 l3->free_objects -= cachep->num;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002769 slab_destroy(cachep, slabp);
2770 } else {
Christoph Lametere498be72005-09-09 13:03:32 -07002771 list_add(&slabp->list, &l3->slabs_free);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002772 }
2773 } else {
2774 /* Unconditionally move a slab to the end of the
2775 * partial list on free - maximum time for the
2776 * other objects to be freed, too.
2777 */
Christoph Lametere498be72005-09-09 13:03:32 -07002778 list_add_tail(&slabp->list, &l3->slabs_partial);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002779 }
2780 }
2781}
2782
2783static void cache_flusharray(kmem_cache_t *cachep, struct array_cache *ac)
2784{
2785 int batchcount;
Christoph Lametere498be72005-09-09 13:03:32 -07002786 struct kmem_list3 *l3;
Christoph Lameterff694162005-09-22 21:44:02 -07002787 int node = numa_node_id();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002788
2789 batchcount = ac->batchcount;
2790#if DEBUG
2791 BUG_ON(!batchcount || batchcount > ac->avail);
2792#endif
2793 check_irq_off();
Christoph Lameterff694162005-09-22 21:44:02 -07002794 l3 = cachep->nodelists[node];
Christoph Lametere498be72005-09-09 13:03:32 -07002795 spin_lock(&l3->list_lock);
2796 if (l3->shared) {
2797 struct array_cache *shared_array = l3->shared;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002798 int max = shared_array->limit - shared_array->avail;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002799 if (max) {
2800 if (batchcount > max)
2801 batchcount = max;
Christoph Lametere498be72005-09-09 13:03:32 -07002802 memcpy(&(shared_array->entry[shared_array->avail]),
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002803 ac->entry, sizeof(void *) * batchcount);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002804 shared_array->avail += batchcount;
2805 goto free_done;
2806 }
2807 }
2808
Christoph Lameterff694162005-09-22 21:44:02 -07002809 free_block(cachep, ac->entry, batchcount, node);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002810 free_done:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002811#if STATS
2812 {
2813 int i = 0;
2814 struct list_head *p;
2815
Christoph Lametere498be72005-09-09 13:03:32 -07002816 p = l3->slabs_free.next;
2817 while (p != &(l3->slabs_free)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002818 struct slab *slabp;
2819
2820 slabp = list_entry(p, struct slab, list);
2821 BUG_ON(slabp->inuse);
2822
2823 i++;
2824 p = p->next;
2825 }
2826 STATS_SET_FREEABLE(cachep, i);
2827 }
2828#endif
Christoph Lametere498be72005-09-09 13:03:32 -07002829 spin_unlock(&l3->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002830 ac->avail -= batchcount;
Christoph Lametere498be72005-09-09 13:03:32 -07002831 memmove(ac->entry, &(ac->entry[batchcount]),
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002832 sizeof(void *) * ac->avail);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002833}
2834
2835/*
2836 * __cache_free
2837 * Release an obj back to its cache. If the obj has a constructed
2838 * state, it must be in this state _before_ it is released.
2839 *
2840 * Called with disabled ints.
2841 */
2842static inline void __cache_free(kmem_cache_t *cachep, void *objp)
2843{
2844 struct array_cache *ac = ac_data(cachep);
2845
2846 check_irq_off();
2847 objp = cache_free_debugcheck(cachep, objp, __builtin_return_address(0));
2848
Christoph Lametere498be72005-09-09 13:03:32 -07002849 /* Make sure we are not freeing a object from another
2850 * node to the array cache on this cpu.
2851 */
2852#ifdef CONFIG_NUMA
2853 {
2854 struct slab *slabp;
Pekka Enberg065d41c2005-11-13 16:06:46 -08002855 slabp = page_get_slab(virt_to_page(objp));
Christoph Lametere498be72005-09-09 13:03:32 -07002856 if (unlikely(slabp->nodeid != numa_node_id())) {
2857 struct array_cache *alien = NULL;
2858 int nodeid = slabp->nodeid;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002859 struct kmem_list3 *l3 =
2860 cachep->nodelists[numa_node_id()];
Christoph Lametere498be72005-09-09 13:03:32 -07002861
2862 STATS_INC_NODEFREES(cachep);
2863 if (l3->alien && l3->alien[nodeid]) {
2864 alien = l3->alien[nodeid];
2865 spin_lock(&alien->lock);
2866 if (unlikely(alien->avail == alien->limit))
2867 __drain_alien_cache(cachep,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002868 alien, nodeid);
Christoph Lametere498be72005-09-09 13:03:32 -07002869 alien->entry[alien->avail++] = objp;
2870 spin_unlock(&alien->lock);
2871 } else {
2872 spin_lock(&(cachep->nodelists[nodeid])->
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002873 list_lock);
Christoph Lameterff694162005-09-22 21:44:02 -07002874 free_block(cachep, &objp, 1, nodeid);
Christoph Lametere498be72005-09-09 13:03:32 -07002875 spin_unlock(&(cachep->nodelists[nodeid])->
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002876 list_lock);
Christoph Lametere498be72005-09-09 13:03:32 -07002877 }
2878 return;
2879 }
2880 }
2881#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07002882 if (likely(ac->avail < ac->limit)) {
2883 STATS_INC_FREEHIT(cachep);
Christoph Lametere498be72005-09-09 13:03:32 -07002884 ac->entry[ac->avail++] = objp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002885 return;
2886 } else {
2887 STATS_INC_FREEMISS(cachep);
2888 cache_flusharray(cachep, ac);
Christoph Lametere498be72005-09-09 13:03:32 -07002889 ac->entry[ac->avail++] = objp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002890 }
2891}
2892
2893/**
2894 * kmem_cache_alloc - Allocate an object
2895 * @cachep: The cache to allocate from.
2896 * @flags: See kmalloc().
2897 *
2898 * Allocate an object from this cache. The flags are only relevant
2899 * if the cache has no available objects.
2900 */
Al Virodd0fc662005-10-07 07:46:04 +01002901void *kmem_cache_alloc(kmem_cache_t *cachep, gfp_t flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002902{
2903 return __cache_alloc(cachep, flags);
2904}
2905EXPORT_SYMBOL(kmem_cache_alloc);
2906
2907/**
2908 * kmem_ptr_validate - check if an untrusted pointer might
2909 * be a slab entry.
2910 * @cachep: the cache we're checking against
2911 * @ptr: pointer to validate
2912 *
2913 * This verifies that the untrusted pointer looks sane:
2914 * it is _not_ a guarantee that the pointer is actually
2915 * part of the slab cache in question, but it at least
2916 * validates that the pointer can be dereferenced and
2917 * looks half-way sane.
2918 *
2919 * Currently only used for dentry validation.
2920 */
2921int fastcall kmem_ptr_validate(kmem_cache_t *cachep, void *ptr)
2922{
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002923 unsigned long addr = (unsigned long)ptr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002924 unsigned long min_addr = PAGE_OFFSET;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002925 unsigned long align_mask = BYTES_PER_WORD - 1;
Manfred Spraul3dafccf2006-02-01 03:05:42 -08002926 unsigned long size = cachep->buffer_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002927 struct page *page;
2928
2929 if (unlikely(addr < min_addr))
2930 goto out;
2931 if (unlikely(addr > (unsigned long)high_memory - size))
2932 goto out;
2933 if (unlikely(addr & align_mask))
2934 goto out;
2935 if (unlikely(!kern_addr_valid(addr)))
2936 goto out;
2937 if (unlikely(!kern_addr_valid(addr + size - 1)))
2938 goto out;
2939 page = virt_to_page(ptr);
2940 if (unlikely(!PageSlab(page)))
2941 goto out;
Pekka Enberg065d41c2005-11-13 16:06:46 -08002942 if (unlikely(page_get_cache(page) != cachep))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002943 goto out;
2944 return 1;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08002945 out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002946 return 0;
2947}
2948
2949#ifdef CONFIG_NUMA
2950/**
2951 * kmem_cache_alloc_node - Allocate an object on the specified node
2952 * @cachep: The cache to allocate from.
2953 * @flags: See kmalloc().
2954 * @nodeid: node number of the target node.
2955 *
2956 * Identical to kmem_cache_alloc, except that this function is slow
2957 * and can sleep. And it will allocate memory on the given node, which
2958 * can improve the performance for cpu bound structures.
Christoph Lametere498be72005-09-09 13:03:32 -07002959 * New and improved: it will now make sure that the object gets
2960 * put on the correct node list so that there is no false sharing.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002961 */
Al Virodd0fc662005-10-07 07:46:04 +01002962void *kmem_cache_alloc_node(kmem_cache_t *cachep, gfp_t flags, int nodeid)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002963{
Christoph Lametere498be72005-09-09 13:03:32 -07002964 unsigned long save_flags;
2965 void *ptr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002966
Christoph Lametere498be72005-09-09 13:03:32 -07002967 cache_alloc_debugcheck_before(cachep, flags);
2968 local_irq_save(save_flags);
Christoph Lameter18f820f2006-02-01 03:05:43 -08002969
2970 if (nodeid == -1 || nodeid == numa_node_id() ||
2971 !cachep->nodelists[nodeid])
Alok N Kataria5c382302005-09-27 21:45:46 -07002972 ptr = ____cache_alloc(cachep, flags);
2973 else
2974 ptr = __cache_alloc_node(cachep, flags, nodeid);
Christoph Lametere498be72005-09-09 13:03:32 -07002975 local_irq_restore(save_flags);
Christoph Lameter18f820f2006-02-01 03:05:43 -08002976
2977 ptr = cache_alloc_debugcheck_after(cachep, flags, ptr,
2978 __builtin_return_address(0));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002979
Christoph Lametere498be72005-09-09 13:03:32 -07002980 return ptr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002981}
2982EXPORT_SYMBOL(kmem_cache_alloc_node);
2983
Al Virodd0fc662005-10-07 07:46:04 +01002984void *kmalloc_node(size_t size, gfp_t flags, int node)
Manfred Spraul97e2bde2005-05-01 08:58:38 -07002985{
2986 kmem_cache_t *cachep;
2987
2988 cachep = kmem_find_general_cachep(size, flags);
2989 if (unlikely(cachep == NULL))
2990 return NULL;
2991 return kmem_cache_alloc_node(cachep, flags, node);
2992}
2993EXPORT_SYMBOL(kmalloc_node);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002994#endif
2995
2996/**
2997 * kmalloc - allocate memory
2998 * @size: how many bytes of memory are required.
2999 * @flags: the type of memory to allocate.
3000 *
3001 * kmalloc is the normal method of allocating memory
3002 * in the kernel.
3003 *
3004 * The @flags argument may be one of:
3005 *
3006 * %GFP_USER - Allocate memory on behalf of user. May sleep.
3007 *
3008 * %GFP_KERNEL - Allocate normal kernel ram. May sleep.
3009 *
3010 * %GFP_ATOMIC - Allocation will not sleep. Use inside interrupt handlers.
3011 *
3012 * Additionally, the %GFP_DMA flag may be set to indicate the memory
3013 * must be suitable for DMA. This can mean different things on different
3014 * platforms. For example, on i386, it means that the memory must come
3015 * from the first 16MB.
3016 */
Al Virodd0fc662005-10-07 07:46:04 +01003017void *__kmalloc(size_t size, gfp_t flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003018{
3019 kmem_cache_t *cachep;
3020
Manfred Spraul97e2bde2005-05-01 08:58:38 -07003021 /* If you want to save a few bytes .text space: replace
3022 * __ with kmem_.
3023 * Then kmalloc uses the uninlined functions instead of the inline
3024 * functions.
3025 */
3026 cachep = __find_general_cachep(size, flags);
Andrew Mortondbdb9042005-09-23 13:24:10 -07003027 if (unlikely(cachep == NULL))
3028 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003029 return __cache_alloc(cachep, flags);
3030}
3031EXPORT_SYMBOL(__kmalloc);
3032
3033#ifdef CONFIG_SMP
3034/**
3035 * __alloc_percpu - allocate one copy of the object for every present
3036 * cpu in the system, zeroing them.
3037 * Objects should be dereferenced using the per_cpu_ptr macro only.
3038 *
3039 * @size: how many bytes of memory are required.
Linus Torvalds1da177e2005-04-16 15:20:36 -07003040 */
Pekka Enbergf9f75002006-01-08 01:00:33 -08003041void *__alloc_percpu(size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003042{
3043 int i;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003044 struct percpu_data *pdata = kmalloc(sizeof(*pdata), GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003045
3046 if (!pdata)
3047 return NULL;
3048
Christoph Lametere498be72005-09-09 13:03:32 -07003049 /*
3050 * Cannot use for_each_online_cpu since a cpu may come online
3051 * and we have no way of figuring out how to fix the array
3052 * that we have allocated then....
3053 */
3054 for_each_cpu(i) {
3055 int node = cpu_to_node(i);
3056
3057 if (node_online(node))
3058 pdata->ptrs[i] = kmalloc_node(size, GFP_KERNEL, node);
3059 else
3060 pdata->ptrs[i] = kmalloc(size, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003061
3062 if (!pdata->ptrs[i])
3063 goto unwind_oom;
3064 memset(pdata->ptrs[i], 0, size);
3065 }
3066
3067 /* Catch derefs w/o wrappers */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003068 return (void *)(~(unsigned long)pdata);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003069
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003070 unwind_oom:
Linus Torvalds1da177e2005-04-16 15:20:36 -07003071 while (--i >= 0) {
3072 if (!cpu_possible(i))
3073 continue;
3074 kfree(pdata->ptrs[i]);
3075 }
3076 kfree(pdata);
3077 return NULL;
3078}
3079EXPORT_SYMBOL(__alloc_percpu);
3080#endif
3081
3082/**
3083 * kmem_cache_free - Deallocate an object
3084 * @cachep: The cache the allocation was from.
3085 * @objp: The previously allocated object.
3086 *
3087 * Free an object which was previously allocated from this
3088 * cache.
3089 */
3090void kmem_cache_free(kmem_cache_t *cachep, void *objp)
3091{
3092 unsigned long flags;
3093
3094 local_irq_save(flags);
3095 __cache_free(cachep, objp);
3096 local_irq_restore(flags);
3097}
3098EXPORT_SYMBOL(kmem_cache_free);
3099
3100/**
Linus Torvalds1da177e2005-04-16 15:20:36 -07003101 * kfree - free previously allocated memory
3102 * @objp: pointer returned by kmalloc.
3103 *
Pekka Enberg80e93ef2005-09-09 13:10:16 -07003104 * If @objp is NULL, no operation is performed.
3105 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07003106 * Don't free memory not originally allocated by kmalloc()
3107 * or you will run into trouble.
3108 */
3109void kfree(const void *objp)
3110{
3111 kmem_cache_t *c;
3112 unsigned long flags;
3113
3114 if (unlikely(!objp))
3115 return;
3116 local_irq_save(flags);
3117 kfree_debugcheck(objp);
Pekka Enberg065d41c2005-11-13 16:06:46 -08003118 c = page_get_cache(virt_to_page(objp));
Manfred Spraul3dafccf2006-02-01 03:05:42 -08003119 mutex_debug_check_no_locks_freed(objp, obj_size(c));
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003120 __cache_free(c, (void *)objp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003121 local_irq_restore(flags);
3122}
3123EXPORT_SYMBOL(kfree);
3124
3125#ifdef CONFIG_SMP
3126/**
3127 * free_percpu - free previously allocated percpu memory
3128 * @objp: pointer returned by alloc_percpu.
3129 *
3130 * Don't free memory not originally allocated by alloc_percpu()
3131 * The complemented objp is to check for that.
3132 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003133void free_percpu(const void *objp)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003134{
3135 int i;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003136 struct percpu_data *p = (struct percpu_data *)(~(unsigned long)objp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003137
Christoph Lametere498be72005-09-09 13:03:32 -07003138 /*
3139 * We allocate for all cpus so we cannot use for online cpu here.
3140 */
3141 for_each_cpu(i)
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003142 kfree(p->ptrs[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003143 kfree(p);
3144}
3145EXPORT_SYMBOL(free_percpu);
3146#endif
3147
3148unsigned int kmem_cache_size(kmem_cache_t *cachep)
3149{
Manfred Spraul3dafccf2006-02-01 03:05:42 -08003150 return obj_size(cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003151}
3152EXPORT_SYMBOL(kmem_cache_size);
3153
Arnaldo Carvalho de Melo19449722005-06-18 22:46:19 -07003154const char *kmem_cache_name(kmem_cache_t *cachep)
3155{
3156 return cachep->name;
3157}
3158EXPORT_SYMBOL_GPL(kmem_cache_name);
3159
Christoph Lametere498be72005-09-09 13:03:32 -07003160/*
3161 * This initializes kmem_list3 for all nodes.
3162 */
3163static int alloc_kmemlist(kmem_cache_t *cachep)
3164{
3165 int node;
3166 struct kmem_list3 *l3;
3167 int err = 0;
3168
3169 for_each_online_node(node) {
3170 struct array_cache *nc = NULL, *new;
3171 struct array_cache **new_alien = NULL;
3172#ifdef CONFIG_NUMA
3173 if (!(new_alien = alloc_alien_cache(node, cachep->limit)))
3174 goto fail;
3175#endif
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003176 if (!(new = alloc_arraycache(node, (cachep->shared *
3177 cachep->batchcount),
3178 0xbaadf00d)))
Christoph Lametere498be72005-09-09 13:03:32 -07003179 goto fail;
3180 if ((l3 = cachep->nodelists[node])) {
3181
3182 spin_lock_irq(&l3->list_lock);
3183
3184 if ((nc = cachep->nodelists[node]->shared))
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003185 free_block(cachep, nc->entry, nc->avail, node);
Christoph Lametere498be72005-09-09 13:03:32 -07003186
3187 l3->shared = new;
3188 if (!cachep->nodelists[node]->alien) {
3189 l3->alien = new_alien;
3190 new_alien = NULL;
3191 }
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003192 l3->free_limit = (1 + nr_cpus_node(node)) *
3193 cachep->batchcount + cachep->num;
Christoph Lametere498be72005-09-09 13:03:32 -07003194 spin_unlock_irq(&l3->list_lock);
3195 kfree(nc);
3196 free_alien_cache(new_alien);
3197 continue;
3198 }
3199 if (!(l3 = kmalloc_node(sizeof(struct kmem_list3),
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003200 GFP_KERNEL, node)))
Christoph Lametere498be72005-09-09 13:03:32 -07003201 goto fail;
3202
3203 kmem_list3_init(l3);
3204 l3->next_reap = jiffies + REAPTIMEOUT_LIST3 +
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003205 ((unsigned long)cachep) % REAPTIMEOUT_LIST3;
Christoph Lametere498be72005-09-09 13:03:32 -07003206 l3->shared = new;
3207 l3->alien = new_alien;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003208 l3->free_limit = (1 + nr_cpus_node(node)) *
3209 cachep->batchcount + cachep->num;
Christoph Lametere498be72005-09-09 13:03:32 -07003210 cachep->nodelists[node] = l3;
3211 }
3212 return err;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003213 fail:
Christoph Lametere498be72005-09-09 13:03:32 -07003214 err = -ENOMEM;
3215 return err;
3216}
3217
Linus Torvalds1da177e2005-04-16 15:20:36 -07003218struct ccupdate_struct {
3219 kmem_cache_t *cachep;
3220 struct array_cache *new[NR_CPUS];
3221};
3222
3223static void do_ccupdate_local(void *info)
3224{
3225 struct ccupdate_struct *new = (struct ccupdate_struct *)info;
3226 struct array_cache *old;
3227
3228 check_irq_off();
3229 old = ac_data(new->cachep);
Christoph Lametere498be72005-09-09 13:03:32 -07003230
Linus Torvalds1da177e2005-04-16 15:20:36 -07003231 new->cachep->array[smp_processor_id()] = new->new[smp_processor_id()];
3232 new->new[smp_processor_id()] = old;
3233}
3234
Linus Torvalds1da177e2005-04-16 15:20:36 -07003235static int do_tune_cpucache(kmem_cache_t *cachep, int limit, int batchcount,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003236 int shared)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003237{
3238 struct ccupdate_struct new;
Christoph Lametere498be72005-09-09 13:03:32 -07003239 int i, err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003240
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003241 memset(&new.new, 0, sizeof(new.new));
Christoph Lametere498be72005-09-09 13:03:32 -07003242 for_each_online_cpu(i) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003243 new.new[i] =
3244 alloc_arraycache(cpu_to_node(i), limit, batchcount);
Christoph Lametere498be72005-09-09 13:03:32 -07003245 if (!new.new[i]) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003246 for (i--; i >= 0; i--)
3247 kfree(new.new[i]);
Christoph Lametere498be72005-09-09 13:03:32 -07003248 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003249 }
3250 }
3251 new.cachep = cachep;
3252
3253 smp_call_function_all_cpus(do_ccupdate_local, (void *)&new);
Christoph Lametere498be72005-09-09 13:03:32 -07003254
Linus Torvalds1da177e2005-04-16 15:20:36 -07003255 check_irq_on();
3256 spin_lock_irq(&cachep->spinlock);
3257 cachep->batchcount = batchcount;
3258 cachep->limit = limit;
Christoph Lametere498be72005-09-09 13:03:32 -07003259 cachep->shared = shared;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003260 spin_unlock_irq(&cachep->spinlock);
3261
Christoph Lametere498be72005-09-09 13:03:32 -07003262 for_each_online_cpu(i) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003263 struct array_cache *ccold = new.new[i];
3264 if (!ccold)
3265 continue;
Christoph Lametere498be72005-09-09 13:03:32 -07003266 spin_lock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock);
Christoph Lameterff694162005-09-22 21:44:02 -07003267 free_block(cachep, ccold->entry, ccold->avail, cpu_to_node(i));
Christoph Lametere498be72005-09-09 13:03:32 -07003268 spin_unlock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003269 kfree(ccold);
3270 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003271
Christoph Lametere498be72005-09-09 13:03:32 -07003272 err = alloc_kmemlist(cachep);
3273 if (err) {
3274 printk(KERN_ERR "alloc_kmemlist failed for %s, error %d.\n",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003275 cachep->name, -err);
Christoph Lametere498be72005-09-09 13:03:32 -07003276 BUG();
Linus Torvalds1da177e2005-04-16 15:20:36 -07003277 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003278 return 0;
3279}
3280
Linus Torvalds1da177e2005-04-16 15:20:36 -07003281static void enable_cpucache(kmem_cache_t *cachep)
3282{
3283 int err;
3284 int limit, shared;
3285
3286 /* The head array serves three purposes:
3287 * - create a LIFO ordering, i.e. return objects that are cache-warm
3288 * - reduce the number of spinlock operations.
3289 * - reduce the number of linked list operations on the slab and
3290 * bufctl chains: array operations are cheaper.
3291 * The numbers are guessed, we should auto-tune as described by
3292 * Bonwick.
3293 */
Manfred Spraul3dafccf2006-02-01 03:05:42 -08003294 if (cachep->buffer_size > 131072)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003295 limit = 1;
Manfred Spraul3dafccf2006-02-01 03:05:42 -08003296 else if (cachep->buffer_size > PAGE_SIZE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003297 limit = 8;
Manfred Spraul3dafccf2006-02-01 03:05:42 -08003298 else if (cachep->buffer_size > 1024)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003299 limit = 24;
Manfred Spraul3dafccf2006-02-01 03:05:42 -08003300 else if (cachep->buffer_size > 256)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003301 limit = 54;
3302 else
3303 limit = 120;
3304
3305 /* Cpu bound tasks (e.g. network routing) can exhibit cpu bound
3306 * allocation behaviour: Most allocs on one cpu, most free operations
3307 * on another cpu. For these cases, an efficient object passing between
3308 * cpus is necessary. This is provided by a shared array. The array
3309 * replaces Bonwick's magazine layer.
3310 * On uniprocessor, it's functionally equivalent (but less efficient)
3311 * to a larger limit. Thus disabled by default.
3312 */
3313 shared = 0;
3314#ifdef CONFIG_SMP
Manfred Spraul3dafccf2006-02-01 03:05:42 -08003315 if (cachep->buffer_size <= PAGE_SIZE)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003316 shared = 8;
3317#endif
3318
3319#if DEBUG
3320 /* With debugging enabled, large batchcount lead to excessively
3321 * long periods with disabled local interrupts. Limit the
3322 * batchcount
3323 */
3324 if (limit > 32)
3325 limit = 32;
3326#endif
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003327 err = do_tune_cpucache(cachep, limit, (limit + 1) / 2, shared);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003328 if (err)
3329 printk(KERN_ERR "enable_cpucache failed for %s, error %d.\n",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003330 cachep->name, -err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003331}
3332
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003333static void drain_array_locked(kmem_cache_t *cachep, struct array_cache *ac,
3334 int force, int node)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003335{
3336 int tofree;
3337
Christoph Lametere498be72005-09-09 13:03:32 -07003338 check_spinlock_acquired_node(cachep, node);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003339 if (ac->touched && !force) {
3340 ac->touched = 0;
3341 } else if (ac->avail) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003342 tofree = force ? ac->avail : (ac->limit + 4) / 5;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003343 if (tofree > ac->avail) {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003344 tofree = (ac->avail + 1) / 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003345 }
Christoph Lameterff694162005-09-22 21:44:02 -07003346 free_block(cachep, ac->entry, tofree, node);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003347 ac->avail -= tofree;
Christoph Lametere498be72005-09-09 13:03:32 -07003348 memmove(ac->entry, &(ac->entry[tofree]),
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003349 sizeof(void *) * ac->avail);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003350 }
3351}
3352
3353/**
3354 * cache_reap - Reclaim memory from caches.
Randy Dunlap1e5d5332005-11-07 01:01:06 -08003355 * @unused: unused parameter
Linus Torvalds1da177e2005-04-16 15:20:36 -07003356 *
3357 * Called from workqueue/eventd every few seconds.
3358 * Purpose:
3359 * - clear the per-cpu caches for this CPU.
3360 * - return freeable pages to the main free memory pool.
3361 *
Ingo Molnarfc0abb12006-01-18 17:42:33 -08003362 * If we cannot acquire the cache chain mutex then just give up - we'll
Linus Torvalds1da177e2005-04-16 15:20:36 -07003363 * try again on the next iteration.
3364 */
3365static void cache_reap(void *unused)
3366{
3367 struct list_head *walk;
Christoph Lametere498be72005-09-09 13:03:32 -07003368 struct kmem_list3 *l3;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003369
Ingo Molnarfc0abb12006-01-18 17:42:33 -08003370 if (!mutex_trylock(&cache_chain_mutex)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003371 /* Give up. Setup the next iteration. */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003372 schedule_delayed_work(&__get_cpu_var(reap_work),
3373 REAPTIMEOUT_CPUC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003374 return;
3375 }
3376
3377 list_for_each(walk, &cache_chain) {
3378 kmem_cache_t *searchp;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003379 struct list_head *p;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003380 int tofree;
3381 struct slab *slabp;
3382
3383 searchp = list_entry(walk, kmem_cache_t, next);
3384
3385 if (searchp->flags & SLAB_NO_REAP)
3386 goto next;
3387
3388 check_irq_on();
3389
Christoph Lametere498be72005-09-09 13:03:32 -07003390 l3 = searchp->nodelists[numa_node_id()];
3391 if (l3->alien)
3392 drain_alien_cache(searchp, l3);
3393 spin_lock_irq(&l3->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003394
Christoph Lametere498be72005-09-09 13:03:32 -07003395 drain_array_locked(searchp, ac_data(searchp), 0,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003396 numa_node_id());
Linus Torvalds1da177e2005-04-16 15:20:36 -07003397
Christoph Lametere498be72005-09-09 13:03:32 -07003398 if (time_after(l3->next_reap, jiffies))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003399 goto next_unlock;
3400
Christoph Lametere498be72005-09-09 13:03:32 -07003401 l3->next_reap = jiffies + REAPTIMEOUT_LIST3;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003402
Christoph Lametere498be72005-09-09 13:03:32 -07003403 if (l3->shared)
3404 drain_array_locked(searchp, l3->shared, 0,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003405 numa_node_id());
Linus Torvalds1da177e2005-04-16 15:20:36 -07003406
Christoph Lametere498be72005-09-09 13:03:32 -07003407 if (l3->free_touched) {
3408 l3->free_touched = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003409 goto next_unlock;
3410 }
3411
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003412 tofree =
3413 (l3->free_limit + 5 * searchp->num -
3414 1) / (5 * searchp->num);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003415 do {
Christoph Lametere498be72005-09-09 13:03:32 -07003416 p = l3->slabs_free.next;
3417 if (p == &(l3->slabs_free))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003418 break;
3419
3420 slabp = list_entry(p, struct slab, list);
3421 BUG_ON(slabp->inuse);
3422 list_del(&slabp->list);
3423 STATS_INC_REAPED(searchp);
3424
3425 /* Safe to drop the lock. The slab is no longer
3426 * linked to the cache.
3427 * searchp cannot disappear, we hold
3428 * cache_chain_lock
3429 */
Christoph Lametere498be72005-09-09 13:03:32 -07003430 l3->free_objects -= searchp->num;
3431 spin_unlock_irq(&l3->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003432 slab_destroy(searchp, slabp);
Christoph Lametere498be72005-09-09 13:03:32 -07003433 spin_lock_irq(&l3->list_lock);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003434 } while (--tofree > 0);
3435 next_unlock:
Christoph Lametere498be72005-09-09 13:03:32 -07003436 spin_unlock_irq(&l3->list_lock);
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003437 next:
Linus Torvalds1da177e2005-04-16 15:20:36 -07003438 cond_resched();
3439 }
3440 check_irq_on();
Ingo Molnarfc0abb12006-01-18 17:42:33 -08003441 mutex_unlock(&cache_chain_mutex);
Christoph Lameter4ae7c032005-06-21 17:14:57 -07003442 drain_remote_pages();
Linus Torvalds1da177e2005-04-16 15:20:36 -07003443 /* Setup the next iteration */
Manfred Spraulcd61ef62005-11-07 00:58:02 -08003444 schedule_delayed_work(&__get_cpu_var(reap_work), REAPTIMEOUT_CPUC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003445}
3446
3447#ifdef CONFIG_PROC_FS
3448
Pekka Enberg85289f92006-01-08 01:00:36 -08003449static void print_slabinfo_header(struct seq_file *m)
3450{
3451 /*
3452 * Output format version, so at least we can change it
3453 * without _too_ many complaints.
3454 */
3455#if STATS
3456 seq_puts(m, "slabinfo - version: 2.1 (statistics)\n");
3457#else
3458 seq_puts(m, "slabinfo - version: 2.1\n");
3459#endif
3460 seq_puts(m, "# name <active_objs> <num_objs> <objsize> "
3461 "<objperslab> <pagesperslab>");
3462 seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
3463 seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
3464#if STATS
3465 seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> "
3466 "<error> <maxfreeable> <nodeallocs> <remotefrees>");
3467 seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>");
3468#endif
3469 seq_putc(m, '\n');
3470}
3471
Linus Torvalds1da177e2005-04-16 15:20:36 -07003472static void *s_start(struct seq_file *m, loff_t *pos)
3473{
3474 loff_t n = *pos;
3475 struct list_head *p;
3476
Ingo Molnarfc0abb12006-01-18 17:42:33 -08003477 mutex_lock(&cache_chain_mutex);
Pekka Enberg85289f92006-01-08 01:00:36 -08003478 if (!n)
3479 print_slabinfo_header(m);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003480 p = cache_chain.next;
3481 while (n--) {
3482 p = p->next;
3483 if (p == &cache_chain)
3484 return NULL;
3485 }
3486 return list_entry(p, kmem_cache_t, next);
3487}
3488
3489static void *s_next(struct seq_file *m, void *p, loff_t *pos)
3490{
3491 kmem_cache_t *cachep = p;
3492 ++*pos;
3493 return cachep->next.next == &cache_chain ? NULL
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003494 : list_entry(cachep->next.next, kmem_cache_t, next);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003495}
3496
3497static void s_stop(struct seq_file *m, void *p)
3498{
Ingo Molnarfc0abb12006-01-18 17:42:33 -08003499 mutex_unlock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003500}
3501
3502static int s_show(struct seq_file *m, void *p)
3503{
3504 kmem_cache_t *cachep = p;
3505 struct list_head *q;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003506 struct slab *slabp;
3507 unsigned long active_objs;
3508 unsigned long num_objs;
3509 unsigned long active_slabs = 0;
3510 unsigned long num_slabs, free_objects = 0, shared_avail = 0;
Christoph Lametere498be72005-09-09 13:03:32 -07003511 const char *name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003512 char *error = NULL;
Christoph Lametere498be72005-09-09 13:03:32 -07003513 int node;
3514 struct kmem_list3 *l3;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003515
3516 check_irq_on();
3517 spin_lock_irq(&cachep->spinlock);
3518 active_objs = 0;
3519 num_slabs = 0;
Christoph Lametere498be72005-09-09 13:03:32 -07003520 for_each_online_node(node) {
3521 l3 = cachep->nodelists[node];
3522 if (!l3)
3523 continue;
3524
3525 spin_lock(&l3->list_lock);
3526
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003527 list_for_each(q, &l3->slabs_full) {
Christoph Lametere498be72005-09-09 13:03:32 -07003528 slabp = list_entry(q, struct slab, list);
3529 if (slabp->inuse != cachep->num && !error)
3530 error = "slabs_full accounting error";
3531 active_objs += cachep->num;
3532 active_slabs++;
3533 }
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003534 list_for_each(q, &l3->slabs_partial) {
Christoph Lametere498be72005-09-09 13:03:32 -07003535 slabp = list_entry(q, struct slab, list);
3536 if (slabp->inuse == cachep->num && !error)
3537 error = "slabs_partial inuse accounting error";
3538 if (!slabp->inuse && !error)
3539 error = "slabs_partial/inuse accounting error";
3540 active_objs += slabp->inuse;
3541 active_slabs++;
3542 }
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003543 list_for_each(q, &l3->slabs_free) {
Christoph Lametere498be72005-09-09 13:03:32 -07003544 slabp = list_entry(q, struct slab, list);
3545 if (slabp->inuse && !error)
3546 error = "slabs_free/inuse accounting error";
3547 num_slabs++;
3548 }
3549 free_objects += l3->free_objects;
3550 shared_avail += l3->shared->avail;
3551
3552 spin_unlock(&l3->list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003553 }
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003554 num_slabs += active_slabs;
3555 num_objs = num_slabs * cachep->num;
Christoph Lametere498be72005-09-09 13:03:32 -07003556 if (num_objs - active_objs != free_objects && !error)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003557 error = "free_objects accounting error";
3558
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003559 name = cachep->name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003560 if (error)
3561 printk(KERN_ERR "slab: cache %s error: %s\n", name, error);
3562
3563 seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d",
Manfred Spraul3dafccf2006-02-01 03:05:42 -08003564 name, active_objs, num_objs, cachep->buffer_size,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003565 cachep->num, (1 << cachep->gfporder));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003566 seq_printf(m, " : tunables %4u %4u %4u",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003567 cachep->limit, cachep->batchcount, cachep->shared);
Christoph Lametere498be72005-09-09 13:03:32 -07003568 seq_printf(m, " : slabdata %6lu %6lu %6lu",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003569 active_slabs, num_slabs, shared_avail);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003570#if STATS
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003571 { /* list3 stats */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003572 unsigned long high = cachep->high_mark;
3573 unsigned long allocs = cachep->num_allocations;
3574 unsigned long grown = cachep->grown;
3575 unsigned long reaped = cachep->reaped;
3576 unsigned long errors = cachep->errors;
3577 unsigned long max_freeable = cachep->max_freeable;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003578 unsigned long node_allocs = cachep->node_allocs;
Christoph Lametere498be72005-09-09 13:03:32 -07003579 unsigned long node_frees = cachep->node_frees;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003580
Christoph Lametere498be72005-09-09 13:03:32 -07003581 seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu \
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003582 %4lu %4lu %4lu %4lu", allocs, high, grown, reaped, errors, max_freeable, node_allocs, node_frees);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003583 }
3584 /* cpu stats */
3585 {
3586 unsigned long allochit = atomic_read(&cachep->allochit);
3587 unsigned long allocmiss = atomic_read(&cachep->allocmiss);
3588 unsigned long freehit = atomic_read(&cachep->freehit);
3589 unsigned long freemiss = atomic_read(&cachep->freemiss);
3590
3591 seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu",
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003592 allochit, allocmiss, freehit, freemiss);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003593 }
3594#endif
3595 seq_putc(m, '\n');
3596 spin_unlock_irq(&cachep->spinlock);
3597 return 0;
3598}
3599
3600/*
3601 * slabinfo_op - iterator that generates /proc/slabinfo
3602 *
3603 * Output layout:
3604 * cache-name
3605 * num-active-objs
3606 * total-objs
3607 * object size
3608 * num-active-slabs
3609 * total-slabs
3610 * num-pages-per-slab
3611 * + further values on SMP and with statistics enabled
3612 */
3613
3614struct seq_operations slabinfo_op = {
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003615 .start = s_start,
3616 .next = s_next,
3617 .stop = s_stop,
3618 .show = s_show,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003619};
3620
3621#define MAX_SLABINFO_WRITE 128
3622/**
3623 * slabinfo_write - Tuning for the slab allocator
3624 * @file: unused
3625 * @buffer: user buffer
3626 * @count: data length
3627 * @ppos: unused
3628 */
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003629ssize_t slabinfo_write(struct file *file, const char __user * buffer,
3630 size_t count, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003631{
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003632 char kbuf[MAX_SLABINFO_WRITE + 1], *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003633 int limit, batchcount, shared, res;
3634 struct list_head *p;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003635
Linus Torvalds1da177e2005-04-16 15:20:36 -07003636 if (count > MAX_SLABINFO_WRITE)
3637 return -EINVAL;
3638 if (copy_from_user(&kbuf, buffer, count))
3639 return -EFAULT;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003640 kbuf[MAX_SLABINFO_WRITE] = '\0';
Linus Torvalds1da177e2005-04-16 15:20:36 -07003641
3642 tmp = strchr(kbuf, ' ');
3643 if (!tmp)
3644 return -EINVAL;
3645 *tmp = '\0';
3646 tmp++;
3647 if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3)
3648 return -EINVAL;
3649
3650 /* Find the cache in the chain of caches. */
Ingo Molnarfc0abb12006-01-18 17:42:33 -08003651 mutex_lock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003652 res = -EINVAL;
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003653 list_for_each(p, &cache_chain) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07003654 kmem_cache_t *cachep = list_entry(p, kmem_cache_t, next);
3655
3656 if (!strcmp(cachep->name, kbuf)) {
3657 if (limit < 1 ||
3658 batchcount < 1 ||
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003659 batchcount > limit || shared < 0) {
Christoph Lametere498be72005-09-09 13:03:32 -07003660 res = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003661 } else {
Christoph Lametere498be72005-09-09 13:03:32 -07003662 res = do_tune_cpucache(cachep, limit,
Pekka Enbergb28a02d2006-01-08 01:00:37 -08003663 batchcount, shared);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003664 }
3665 break;
3666 }
3667 }
Ingo Molnarfc0abb12006-01-18 17:42:33 -08003668 mutex_unlock(&cache_chain_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003669 if (res >= 0)
3670 res = count;
3671 return res;
3672}
3673#endif
3674
Manfred Spraul00e145b2005-09-03 15:55:07 -07003675/**
3676 * ksize - get the actual amount of memory allocated for a given object
3677 * @objp: Pointer to the object
3678 *
3679 * kmalloc may internally round up allocations and return more memory
3680 * than requested. ksize() can be used to determine the actual amount of
3681 * memory allocated. The caller may use this additional memory, even though
3682 * a smaller amount of memory was initially specified with the kmalloc call.
3683 * The caller must guarantee that objp points to a valid object previously
3684 * allocated with either kmalloc() or kmem_cache_alloc(). The object
3685 * must not be freed during the duration of the call.
3686 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003687unsigned int ksize(const void *objp)
3688{
Manfred Spraul00e145b2005-09-03 15:55:07 -07003689 if (unlikely(objp == NULL))
3690 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003691
Manfred Spraul3dafccf2006-02-01 03:05:42 -08003692 return obj_size(page_get_cache(virt_to_page(objp)));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003693}