slub: When allocating a new slab also prep the first object
[deliverable/linux.git] / mm / slub.c
CommitLineData
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1/*
2 * SLUB: A slab allocator that limits cache line use instead of queuing
3 * objects in per cpu and per node lists.
4 *
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5 * The allocator synchronizes using per slab locks or atomic operatios
6 * and only uses a centralized lock to manage a pool of partial slabs.
81819f0f 7 *
cde53535 8 * (C) 2007 SGI, Christoph Lameter
881db7fb 9 * (C) 2011 Linux Foundation, Christoph Lameter
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10 */
11
12#include <linux/mm.h>
1eb5ac64 13#include <linux/swap.h> /* struct reclaim_state */
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14#include <linux/module.h>
15#include <linux/bit_spinlock.h>
16#include <linux/interrupt.h>
17#include <linux/bitops.h>
18#include <linux/slab.h>
7b3c3a50 19#include <linux/proc_fs.h>
81819f0f 20#include <linux/seq_file.h>
5a896d9e 21#include <linux/kmemcheck.h>
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22#include <linux/cpu.h>
23#include <linux/cpuset.h>
24#include <linux/mempolicy.h>
25#include <linux/ctype.h>
3ac7fe5a 26#include <linux/debugobjects.h>
81819f0f 27#include <linux/kallsyms.h>
b9049e23 28#include <linux/memory.h>
f8bd2258 29#include <linux/math64.h>
773ff60e 30#include <linux/fault-inject.h>
81819f0f 31
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32#include <trace/events/kmem.h>
33
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34/*
35 * Lock order:
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36 * 1. slub_lock (Global Semaphore)
37 * 2. node->list_lock
38 * 3. slab_lock(page) (Only on some arches and for debugging)
81819f0f 39 *
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40 * slub_lock
41 *
42 * The role of the slub_lock is to protect the list of all the slabs
43 * and to synchronize major metadata changes to slab cache structures.
44 *
45 * The slab_lock is only used for debugging and on arches that do not
46 * have the ability to do a cmpxchg_double. It only protects the second
47 * double word in the page struct. Meaning
48 * A. page->freelist -> List of object free in a page
49 * B. page->counters -> Counters of objects
50 * C. page->frozen -> frozen state
51 *
52 * If a slab is frozen then it is exempt from list management. It is not
53 * on any list. The processor that froze the slab is the one who can
54 * perform list operations on the page. Other processors may put objects
55 * onto the freelist but the processor that froze the slab is the only
56 * one that can retrieve the objects from the page's freelist.
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57 *
58 * The list_lock protects the partial and full list on each node and
59 * the partial slab counter. If taken then no new slabs may be added or
60 * removed from the lists nor make the number of partial slabs be modified.
61 * (Note that the total number of slabs is an atomic value that may be
62 * modified without taking the list lock).
63 *
64 * The list_lock is a centralized lock and thus we avoid taking it as
65 * much as possible. As long as SLUB does not have to handle partial
66 * slabs, operations can continue without any centralized lock. F.e.
67 * allocating a long series of objects that fill up slabs does not require
68 * the list lock.
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69 * Interrupts are disabled during allocation and deallocation in order to
70 * make the slab allocator safe to use in the context of an irq. In addition
71 * interrupts are disabled to ensure that the processor does not change
72 * while handling per_cpu slabs, due to kernel preemption.
73 *
74 * SLUB assigns one slab for allocation to each processor.
75 * Allocations only occur from these slabs called cpu slabs.
76 *
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77 * Slabs with free elements are kept on a partial list and during regular
78 * operations no list for full slabs is used. If an object in a full slab is
81819f0f 79 * freed then the slab will show up again on the partial lists.
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80 * We track full slabs for debugging purposes though because otherwise we
81 * cannot scan all objects.
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82 *
83 * Slabs are freed when they become empty. Teardown and setup is
84 * minimal so we rely on the page allocators per cpu caches for
85 * fast frees and allocs.
86 *
87 * Overloading of page flags that are otherwise used for LRU management.
88 *
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89 * PageActive The slab is frozen and exempt from list processing.
90 * This means that the slab is dedicated to a purpose
91 * such as satisfying allocations for a specific
92 * processor. Objects may be freed in the slab while
93 * it is frozen but slab_free will then skip the usual
94 * list operations. It is up to the processor holding
95 * the slab to integrate the slab into the slab lists
96 * when the slab is no longer needed.
97 *
98 * One use of this flag is to mark slabs that are
99 * used for allocations. Then such a slab becomes a cpu
100 * slab. The cpu slab may be equipped with an additional
dfb4f096 101 * freelist that allows lockless access to
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102 * free objects in addition to the regular freelist
103 * that requires the slab lock.
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104 *
105 * PageError Slab requires special handling due to debug
106 * options set. This moves slab handling out of
894b8788 107 * the fast path and disables lockless freelists.
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108 */
109
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110#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
111 SLAB_TRACE | SLAB_DEBUG_FREE)
112
113static inline int kmem_cache_debug(struct kmem_cache *s)
114{
5577bd8a 115#ifdef CONFIG_SLUB_DEBUG
af537b0a 116 return unlikely(s->flags & SLAB_DEBUG_FLAGS);
5577bd8a 117#else
af537b0a 118 return 0;
5577bd8a 119#endif
af537b0a 120}
5577bd8a 121
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122/*
123 * Issues still to be resolved:
124 *
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125 * - Support PAGE_ALLOC_DEBUG. Should be easy to do.
126 *
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127 * - Variable sizing of the per node arrays
128 */
129
130/* Enable to test recovery from slab corruption on boot */
131#undef SLUB_RESILIENCY_TEST
132
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133/* Enable to log cmpxchg failures */
134#undef SLUB_DEBUG_CMPXCHG
135
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136/*
137 * Mininum number of partial slabs. These will be left on the partial
138 * lists even if they are empty. kmem_cache_shrink may reclaim them.
139 */
76be8950 140#define MIN_PARTIAL 5
e95eed57 141
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142/*
143 * Maximum number of desirable partial slabs.
144 * The existence of more partial slabs makes kmem_cache_shrink
145 * sort the partial list by the number of objects in the.
146 */
147#define MAX_PARTIAL 10
148
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149#define DEBUG_DEFAULT_FLAGS (SLAB_DEBUG_FREE | SLAB_RED_ZONE | \
150 SLAB_POISON | SLAB_STORE_USER)
672bba3a 151
fa5ec8a1 152/*
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153 * Debugging flags that require metadata to be stored in the slab. These get
154 * disabled when slub_debug=O is used and a cache's min order increases with
155 * metadata.
fa5ec8a1 156 */
3de47213 157#define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
fa5ec8a1 158
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159/*
160 * Set of flags that will prevent slab merging
161 */
162#define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
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163 SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \
164 SLAB_FAILSLAB)
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165
166#define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \
5a896d9e 167 SLAB_CACHE_DMA | SLAB_NOTRACK)
81819f0f 168
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169#define OO_SHIFT 16
170#define OO_MASK ((1 << OO_SHIFT) - 1)
50d5c41c 171#define MAX_OBJS_PER_PAGE 32767 /* since page.objects is u15 */
210b5c06 172
81819f0f 173/* Internal SLUB flags */
f90ec390 174#define __OBJECT_POISON 0x80000000UL /* Poison object */
b789ef51 175#define __CMPXCHG_DOUBLE 0x40000000UL /* Use cmpxchg_double */
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176
177static int kmem_size = sizeof(struct kmem_cache);
178
179#ifdef CONFIG_SMP
180static struct notifier_block slab_notifier;
181#endif
182
183static enum {
184 DOWN, /* No slab functionality available */
51df1142 185 PARTIAL, /* Kmem_cache_node works */
672bba3a 186 UP, /* Everything works but does not show up in sysfs */
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187 SYSFS /* Sysfs up */
188} slab_state = DOWN;
189
190/* A list of all slab caches on the system */
191static DECLARE_RWSEM(slub_lock);
5af328a5 192static LIST_HEAD(slab_caches);
81819f0f 193
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194/*
195 * Tracking user of a slab.
196 */
197struct track {
ce71e27c 198 unsigned long addr; /* Called from address */
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199 int cpu; /* Was running on cpu */
200 int pid; /* Pid context */
201 unsigned long when; /* When did the operation occur */
202};
203
204enum track_item { TRACK_ALLOC, TRACK_FREE };
205
ab4d5ed5 206#ifdef CONFIG_SYSFS
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207static int sysfs_slab_add(struct kmem_cache *);
208static int sysfs_slab_alias(struct kmem_cache *, const char *);
209static void sysfs_slab_remove(struct kmem_cache *);
8ff12cfc 210
81819f0f 211#else
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212static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; }
213static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p)
214 { return 0; }
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215static inline void sysfs_slab_remove(struct kmem_cache *s)
216{
84c1cf62 217 kfree(s->name);
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218 kfree(s);
219}
8ff12cfc 220
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221#endif
222
4fdccdfb 223static inline void stat(const struct kmem_cache *s, enum stat_item si)
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224{
225#ifdef CONFIG_SLUB_STATS
84e554e6 226 __this_cpu_inc(s->cpu_slab->stat[si]);
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227#endif
228}
229
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230/********************************************************************
231 * Core slab cache functions
232 *******************************************************************/
233
234int slab_is_available(void)
235{
236 return slab_state >= UP;
237}
238
239static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
240{
81819f0f 241 return s->node[node];
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242}
243
6446faa2 244/* Verify that a pointer has an address that is valid within a slab page */
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245static inline int check_valid_pointer(struct kmem_cache *s,
246 struct page *page, const void *object)
247{
248 void *base;
249
a973e9dd 250 if (!object)
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251 return 1;
252
a973e9dd 253 base = page_address(page);
39b26464 254 if (object < base || object >= base + page->objects * s->size ||
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255 (object - base) % s->size) {
256 return 0;
257 }
258
259 return 1;
260}
261
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262static inline void *get_freepointer(struct kmem_cache *s, void *object)
263{
264 return *(void **)(object + s->offset);
265}
266
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267static inline void *get_freepointer_safe(struct kmem_cache *s, void *object)
268{
269 void *p;
270
271#ifdef CONFIG_DEBUG_PAGEALLOC
272 probe_kernel_read(&p, (void **)(object + s->offset), sizeof(p));
273#else
274 p = get_freepointer(s, object);
275#endif
276 return p;
277}
278
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279static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp)
280{
281 *(void **)(object + s->offset) = fp;
282}
283
284/* Loop over all objects in a slab */
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285#define for_each_object(__p, __s, __addr, __objects) \
286 for (__p = (__addr); __p < (__addr) + (__objects) * (__s)->size;\
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287 __p += (__s)->size)
288
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289/* Determine object index from a given position */
290static inline int slab_index(void *p, struct kmem_cache *s, void *addr)
291{
292 return (p - addr) / s->size;
293}
294
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295static inline size_t slab_ksize(const struct kmem_cache *s)
296{
297#ifdef CONFIG_SLUB_DEBUG
298 /*
299 * Debugging requires use of the padding between object
300 * and whatever may come after it.
301 */
302 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
303 return s->objsize;
304
305#endif
306 /*
307 * If we have the need to store the freelist pointer
308 * back there or track user information then we can
309 * only use the space before that information.
310 */
311 if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER))
312 return s->inuse;
313 /*
314 * Else we can use all the padding etc for the allocation
315 */
316 return s->size;
317}
318
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319static inline int order_objects(int order, unsigned long size, int reserved)
320{
321 return ((PAGE_SIZE << order) - reserved) / size;
322}
323
834f3d11 324static inline struct kmem_cache_order_objects oo_make(int order,
ab9a0f19 325 unsigned long size, int reserved)
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326{
327 struct kmem_cache_order_objects x = {
ab9a0f19 328 (order << OO_SHIFT) + order_objects(order, size, reserved)
834f3d11
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329 };
330
331 return x;
332}
333
334static inline int oo_order(struct kmem_cache_order_objects x)
335{
210b5c06 336 return x.x >> OO_SHIFT;
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337}
338
339static inline int oo_objects(struct kmem_cache_order_objects x)
340{
210b5c06 341 return x.x & OO_MASK;
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342}
343
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344/*
345 * Per slab locking using the pagelock
346 */
347static __always_inline void slab_lock(struct page *page)
348{
349 bit_spin_lock(PG_locked, &page->flags);
350}
351
352static __always_inline void slab_unlock(struct page *page)
353{
354 __bit_spin_unlock(PG_locked, &page->flags);
355}
356
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357/* Interrupts must be disabled (for the fallback code to work right) */
358static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
359 void *freelist_old, unsigned long counters_old,
360 void *freelist_new, unsigned long counters_new,
361 const char *n)
362{
363 VM_BUG_ON(!irqs_disabled());
364#ifdef CONFIG_CMPXCHG_DOUBLE
365 if (s->flags & __CMPXCHG_DOUBLE) {
366 if (cmpxchg_double(&page->freelist,
367 freelist_old, counters_old,
368 freelist_new, counters_new))
369 return 1;
370 } else
371#endif
372 {
373 slab_lock(page);
374 if (page->freelist == freelist_old && page->counters == counters_old) {
375 page->freelist = freelist_new;
376 page->counters = counters_new;
377 slab_unlock(page);
378 return 1;
379 }
380 slab_unlock(page);
381 }
382
383 cpu_relax();
384 stat(s, CMPXCHG_DOUBLE_FAIL);
385
386#ifdef SLUB_DEBUG_CMPXCHG
387 printk(KERN_INFO "%s %s: cmpxchg double redo ", n, s->name);
388#endif
389
390 return 0;
391}
392
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393static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
394 void *freelist_old, unsigned long counters_old,
395 void *freelist_new, unsigned long counters_new,
396 const char *n)
397{
398#ifdef CONFIG_CMPXCHG_DOUBLE
399 if (s->flags & __CMPXCHG_DOUBLE) {
400 if (cmpxchg_double(&page->freelist,
401 freelist_old, counters_old,
402 freelist_new, counters_new))
403 return 1;
404 } else
405#endif
406 {
1d07171c
CL
407 unsigned long flags;
408
409 local_irq_save(flags);
881db7fb 410 slab_lock(page);
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411 if (page->freelist == freelist_old && page->counters == counters_old) {
412 page->freelist = freelist_new;
413 page->counters = counters_new;
881db7fb 414 slab_unlock(page);
1d07171c 415 local_irq_restore(flags);
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416 return 1;
417 }
881db7fb 418 slab_unlock(page);
1d07171c 419 local_irq_restore(flags);
b789ef51
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420 }
421
422 cpu_relax();
423 stat(s, CMPXCHG_DOUBLE_FAIL);
424
425#ifdef SLUB_DEBUG_CMPXCHG
426 printk(KERN_INFO "%s %s: cmpxchg double redo ", n, s->name);
427#endif
428
429 return 0;
430}
431
41ecc55b 432#ifdef CONFIG_SLUB_DEBUG
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433/*
434 * Determine a map of object in use on a page.
435 *
881db7fb 436 * Node listlock must be held to guarantee that the page does
5f80b13a
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437 * not vanish from under us.
438 */
439static void get_map(struct kmem_cache *s, struct page *page, unsigned long *map)
440{
441 void *p;
442 void *addr = page_address(page);
443
444 for (p = page->freelist; p; p = get_freepointer(s, p))
445 set_bit(slab_index(p, s, addr), map);
446}
447
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448/*
449 * Debug settings:
450 */
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451#ifdef CONFIG_SLUB_DEBUG_ON
452static int slub_debug = DEBUG_DEFAULT_FLAGS;
453#else
41ecc55b 454static int slub_debug;
f0630fff 455#endif
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456
457static char *slub_debug_slabs;
fa5ec8a1 458static int disable_higher_order_debug;
41ecc55b 459
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460/*
461 * Object debugging
462 */
463static void print_section(char *text, u8 *addr, unsigned int length)
464{
465 int i, offset;
466 int newline = 1;
467 char ascii[17];
468
469 ascii[16] = 0;
470
471 for (i = 0; i < length; i++) {
472 if (newline) {
24922684 473 printk(KERN_ERR "%8s 0x%p: ", text, addr + i);
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474 newline = 0;
475 }
06428780 476 printk(KERN_CONT " %02x", addr[i]);
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477 offset = i % 16;
478 ascii[offset] = isgraph(addr[i]) ? addr[i] : '.';
479 if (offset == 15) {
06428780 480 printk(KERN_CONT " %s\n", ascii);
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481 newline = 1;
482 }
483 }
484 if (!newline) {
485 i %= 16;
486 while (i < 16) {
06428780 487 printk(KERN_CONT " ");
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488 ascii[i] = ' ';
489 i++;
490 }
06428780 491 printk(KERN_CONT " %s\n", ascii);
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492 }
493}
494
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495static struct track *get_track(struct kmem_cache *s, void *object,
496 enum track_item alloc)
497{
498 struct track *p;
499
500 if (s->offset)
501 p = object + s->offset + sizeof(void *);
502 else
503 p = object + s->inuse;
504
505 return p + alloc;
506}
507
508static void set_track(struct kmem_cache *s, void *object,
ce71e27c 509 enum track_item alloc, unsigned long addr)
81819f0f 510{
1a00df4a 511 struct track *p = get_track(s, object, alloc);
81819f0f 512
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513 if (addr) {
514 p->addr = addr;
515 p->cpu = smp_processor_id();
88e4ccf2 516 p->pid = current->pid;
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517 p->when = jiffies;
518 } else
519 memset(p, 0, sizeof(struct track));
520}
521
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522static void init_tracking(struct kmem_cache *s, void *object)
523{
24922684
CL
524 if (!(s->flags & SLAB_STORE_USER))
525 return;
526
ce71e27c
EGM
527 set_track(s, object, TRACK_FREE, 0UL);
528 set_track(s, object, TRACK_ALLOC, 0UL);
81819f0f
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529}
530
531static void print_track(const char *s, struct track *t)
532{
533 if (!t->addr)
534 return;
535
7daf705f 536 printk(KERN_ERR "INFO: %s in %pS age=%lu cpu=%u pid=%d\n",
ce71e27c 537 s, (void *)t->addr, jiffies - t->when, t->cpu, t->pid);
24922684
CL
538}
539
540static void print_tracking(struct kmem_cache *s, void *object)
541{
542 if (!(s->flags & SLAB_STORE_USER))
543 return;
544
545 print_track("Allocated", get_track(s, object, TRACK_ALLOC));
546 print_track("Freed", get_track(s, object, TRACK_FREE));
547}
548
549static void print_page_info(struct page *page)
550{
39b26464
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551 printk(KERN_ERR "INFO: Slab 0x%p objects=%u used=%u fp=0x%p flags=0x%04lx\n",
552 page, page->objects, page->inuse, page->freelist, page->flags);
24922684
CL
553
554}
555
556static void slab_bug(struct kmem_cache *s, char *fmt, ...)
557{
558 va_list args;
559 char buf[100];
560
561 va_start(args, fmt);
562 vsnprintf(buf, sizeof(buf), fmt, args);
563 va_end(args);
564 printk(KERN_ERR "========================================"
565 "=====================================\n");
566 printk(KERN_ERR "BUG %s: %s\n", s->name, buf);
567 printk(KERN_ERR "----------------------------------------"
568 "-------------------------------------\n\n");
81819f0f
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569}
570
24922684
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571static void slab_fix(struct kmem_cache *s, char *fmt, ...)
572{
573 va_list args;
574 char buf[100];
575
576 va_start(args, fmt);
577 vsnprintf(buf, sizeof(buf), fmt, args);
578 va_end(args);
579 printk(KERN_ERR "FIX %s: %s\n", s->name, buf);
580}
581
582static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p)
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583{
584 unsigned int off; /* Offset of last byte */
a973e9dd 585 u8 *addr = page_address(page);
24922684
CL
586
587 print_tracking(s, p);
588
589 print_page_info(page);
590
591 printk(KERN_ERR "INFO: Object 0x%p @offset=%tu fp=0x%p\n\n",
592 p, p - addr, get_freepointer(s, p));
593
594 if (p > addr + 16)
595 print_section("Bytes b4", p - 16, 16);
596
0ebd652b 597 print_section("Object", p, min_t(unsigned long, s->objsize, PAGE_SIZE));
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598
599 if (s->flags & SLAB_RED_ZONE)
600 print_section("Redzone", p + s->objsize,
601 s->inuse - s->objsize);
602
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CL
603 if (s->offset)
604 off = s->offset + sizeof(void *);
605 else
606 off = s->inuse;
607
24922684 608 if (s->flags & SLAB_STORE_USER)
81819f0f 609 off += 2 * sizeof(struct track);
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610
611 if (off != s->size)
612 /* Beginning of the filler is the free pointer */
24922684
CL
613 print_section("Padding", p + off, s->size - off);
614
615 dump_stack();
81819f0f
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616}
617
618static void object_err(struct kmem_cache *s, struct page *page,
619 u8 *object, char *reason)
620{
3dc50637 621 slab_bug(s, "%s", reason);
24922684 622 print_trailer(s, page, object);
81819f0f
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623}
624
24922684 625static void slab_err(struct kmem_cache *s, struct page *page, char *fmt, ...)
81819f0f
CL
626{
627 va_list args;
628 char buf[100];
629
24922684
CL
630 va_start(args, fmt);
631 vsnprintf(buf, sizeof(buf), fmt, args);
81819f0f 632 va_end(args);
3dc50637 633 slab_bug(s, "%s", buf);
24922684 634 print_page_info(page);
81819f0f
CL
635 dump_stack();
636}
637
f7cb1933 638static void init_object(struct kmem_cache *s, void *object, u8 val)
81819f0f
CL
639{
640 u8 *p = object;
641
642 if (s->flags & __OBJECT_POISON) {
643 memset(p, POISON_FREE, s->objsize - 1);
06428780 644 p[s->objsize - 1] = POISON_END;
81819f0f
CL
645 }
646
647 if (s->flags & SLAB_RED_ZONE)
f7cb1933 648 memset(p + s->objsize, val, s->inuse - s->objsize);
81819f0f
CL
649}
650
24922684 651static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes)
81819f0f
CL
652{
653 while (bytes) {
654 if (*start != (u8)value)
24922684 655 return start;
81819f0f
CL
656 start++;
657 bytes--;
658 }
24922684
CL
659 return NULL;
660}
661
662static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
663 void *from, void *to)
664{
665 slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data);
666 memset(from, data, to - from);
667}
668
669static int check_bytes_and_report(struct kmem_cache *s, struct page *page,
670 u8 *object, char *what,
06428780 671 u8 *start, unsigned int value, unsigned int bytes)
24922684
CL
672{
673 u8 *fault;
674 u8 *end;
675
676 fault = check_bytes(start, value, bytes);
677 if (!fault)
678 return 1;
679
680 end = start + bytes;
681 while (end > fault && end[-1] == value)
682 end--;
683
684 slab_bug(s, "%s overwritten", what);
685 printk(KERN_ERR "INFO: 0x%p-0x%p. First byte 0x%x instead of 0x%x\n",
686 fault, end - 1, fault[0], value);
687 print_trailer(s, page, object);
688
689 restore_bytes(s, what, value, fault, end);
690 return 0;
81819f0f
CL
691}
692
81819f0f
CL
693/*
694 * Object layout:
695 *
696 * object address
697 * Bytes of the object to be managed.
698 * If the freepointer may overlay the object then the free
699 * pointer is the first word of the object.
672bba3a 700 *
81819f0f
CL
701 * Poisoning uses 0x6b (POISON_FREE) and the last byte is
702 * 0xa5 (POISON_END)
703 *
704 * object + s->objsize
705 * Padding to reach word boundary. This is also used for Redzoning.
672bba3a
CL
706 * Padding is extended by another word if Redzoning is enabled and
707 * objsize == inuse.
708 *
81819f0f
CL
709 * We fill with 0xbb (RED_INACTIVE) for inactive objects and with
710 * 0xcc (RED_ACTIVE) for objects in use.
711 *
712 * object + s->inuse
672bba3a
CL
713 * Meta data starts here.
714 *
81819f0f
CL
715 * A. Free pointer (if we cannot overwrite object on free)
716 * B. Tracking data for SLAB_STORE_USER
672bba3a 717 * C. Padding to reach required alignment boundary or at mininum
6446faa2 718 * one word if debugging is on to be able to detect writes
672bba3a
CL
719 * before the word boundary.
720 *
721 * Padding is done using 0x5a (POISON_INUSE)
81819f0f
CL
722 *
723 * object + s->size
672bba3a 724 * Nothing is used beyond s->size.
81819f0f 725 *
672bba3a
CL
726 * If slabcaches are merged then the objsize and inuse boundaries are mostly
727 * ignored. And therefore no slab options that rely on these boundaries
81819f0f
CL
728 * may be used with merged slabcaches.
729 */
730
81819f0f
CL
731static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p)
732{
733 unsigned long off = s->inuse; /* The end of info */
734
735 if (s->offset)
736 /* Freepointer is placed after the object. */
737 off += sizeof(void *);
738
739 if (s->flags & SLAB_STORE_USER)
740 /* We also have user information there */
741 off += 2 * sizeof(struct track);
742
743 if (s->size == off)
744 return 1;
745
24922684
CL
746 return check_bytes_and_report(s, page, p, "Object padding",
747 p + off, POISON_INUSE, s->size - off);
81819f0f
CL
748}
749
39b26464 750/* Check the pad bytes at the end of a slab page */
81819f0f
CL
751static int slab_pad_check(struct kmem_cache *s, struct page *page)
752{
24922684
CL
753 u8 *start;
754 u8 *fault;
755 u8 *end;
756 int length;
757 int remainder;
81819f0f
CL
758
759 if (!(s->flags & SLAB_POISON))
760 return 1;
761
a973e9dd 762 start = page_address(page);
ab9a0f19 763 length = (PAGE_SIZE << compound_order(page)) - s->reserved;
39b26464
CL
764 end = start + length;
765 remainder = length % s->size;
81819f0f
CL
766 if (!remainder)
767 return 1;
768
39b26464 769 fault = check_bytes(end - remainder, POISON_INUSE, remainder);
24922684
CL
770 if (!fault)
771 return 1;
772 while (end > fault && end[-1] == POISON_INUSE)
773 end--;
774
775 slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1);
39b26464 776 print_section("Padding", end - remainder, remainder);
24922684 777
8a3d271d 778 restore_bytes(s, "slab padding", POISON_INUSE, end - remainder, end);
24922684 779 return 0;
81819f0f
CL
780}
781
782static int check_object(struct kmem_cache *s, struct page *page,
f7cb1933 783 void *object, u8 val)
81819f0f
CL
784{
785 u8 *p = object;
786 u8 *endobject = object + s->objsize;
787
788 if (s->flags & SLAB_RED_ZONE) {
24922684 789 if (!check_bytes_and_report(s, page, object, "Redzone",
f7cb1933 790 endobject, val, s->inuse - s->objsize))
81819f0f 791 return 0;
81819f0f 792 } else {
3adbefee
IM
793 if ((s->flags & SLAB_POISON) && s->objsize < s->inuse) {
794 check_bytes_and_report(s, page, p, "Alignment padding",
795 endobject, POISON_INUSE, s->inuse - s->objsize);
796 }
81819f0f
CL
797 }
798
799 if (s->flags & SLAB_POISON) {
f7cb1933 800 if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) &&
24922684
CL
801 (!check_bytes_and_report(s, page, p, "Poison", p,
802 POISON_FREE, s->objsize - 1) ||
803 !check_bytes_and_report(s, page, p, "Poison",
06428780 804 p + s->objsize - 1, POISON_END, 1)))
81819f0f 805 return 0;
81819f0f
CL
806 /*
807 * check_pad_bytes cleans up on its own.
808 */
809 check_pad_bytes(s, page, p);
810 }
811
f7cb1933 812 if (!s->offset && val == SLUB_RED_ACTIVE)
81819f0f
CL
813 /*
814 * Object and freepointer overlap. Cannot check
815 * freepointer while object is allocated.
816 */
817 return 1;
818
819 /* Check free pointer validity */
820 if (!check_valid_pointer(s, page, get_freepointer(s, p))) {
821 object_err(s, page, p, "Freepointer corrupt");
822 /*
9f6c708e 823 * No choice but to zap it and thus lose the remainder
81819f0f 824 * of the free objects in this slab. May cause
672bba3a 825 * another error because the object count is now wrong.
81819f0f 826 */
a973e9dd 827 set_freepointer(s, p, NULL);
81819f0f
CL
828 return 0;
829 }
830 return 1;
831}
832
833static int check_slab(struct kmem_cache *s, struct page *page)
834{
39b26464
CL
835 int maxobj;
836
81819f0f
CL
837 VM_BUG_ON(!irqs_disabled());
838
839 if (!PageSlab(page)) {
24922684 840 slab_err(s, page, "Not a valid slab page");
81819f0f
CL
841 return 0;
842 }
39b26464 843
ab9a0f19 844 maxobj = order_objects(compound_order(page), s->size, s->reserved);
39b26464
CL
845 if (page->objects > maxobj) {
846 slab_err(s, page, "objects %u > max %u",
847 s->name, page->objects, maxobj);
848 return 0;
849 }
850 if (page->inuse > page->objects) {
24922684 851 slab_err(s, page, "inuse %u > max %u",
39b26464 852 s->name, page->inuse, page->objects);
81819f0f
CL
853 return 0;
854 }
855 /* Slab_pad_check fixes things up after itself */
856 slab_pad_check(s, page);
857 return 1;
858}
859
860/*
672bba3a
CL
861 * Determine if a certain object on a page is on the freelist. Must hold the
862 * slab lock to guarantee that the chains are in a consistent state.
81819f0f
CL
863 */
864static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
865{
866 int nr = 0;
881db7fb 867 void *fp;
81819f0f 868 void *object = NULL;
224a88be 869 unsigned long max_objects;
81819f0f 870
881db7fb 871 fp = page->freelist;
39b26464 872 while (fp && nr <= page->objects) {
81819f0f
CL
873 if (fp == search)
874 return 1;
875 if (!check_valid_pointer(s, page, fp)) {
876 if (object) {
877 object_err(s, page, object,
878 "Freechain corrupt");
a973e9dd 879 set_freepointer(s, object, NULL);
81819f0f
CL
880 break;
881 } else {
24922684 882 slab_err(s, page, "Freepointer corrupt");
a973e9dd 883 page->freelist = NULL;
39b26464 884 page->inuse = page->objects;
24922684 885 slab_fix(s, "Freelist cleared");
81819f0f
CL
886 return 0;
887 }
888 break;
889 }
890 object = fp;
891 fp = get_freepointer(s, object);
892 nr++;
893 }
894
ab9a0f19 895 max_objects = order_objects(compound_order(page), s->size, s->reserved);
210b5c06
CG
896 if (max_objects > MAX_OBJS_PER_PAGE)
897 max_objects = MAX_OBJS_PER_PAGE;
224a88be
CL
898
899 if (page->objects != max_objects) {
900 slab_err(s, page, "Wrong number of objects. Found %d but "
901 "should be %d", page->objects, max_objects);
902 page->objects = max_objects;
903 slab_fix(s, "Number of objects adjusted.");
904 }
39b26464 905 if (page->inuse != page->objects - nr) {
70d71228 906 slab_err(s, page, "Wrong object count. Counter is %d but "
39b26464
CL
907 "counted were %d", page->inuse, page->objects - nr);
908 page->inuse = page->objects - nr;
24922684 909 slab_fix(s, "Object count adjusted.");
81819f0f
CL
910 }
911 return search == NULL;
912}
913
0121c619
CL
914static void trace(struct kmem_cache *s, struct page *page, void *object,
915 int alloc)
3ec09742
CL
916{
917 if (s->flags & SLAB_TRACE) {
918 printk(KERN_INFO "TRACE %s %s 0x%p inuse=%d fp=0x%p\n",
919 s->name,
920 alloc ? "alloc" : "free",
921 object, page->inuse,
922 page->freelist);
923
924 if (!alloc)
925 print_section("Object", (void *)object, s->objsize);
926
927 dump_stack();
928 }
929}
930
c016b0bd
CL
931/*
932 * Hooks for other subsystems that check memory allocations. In a typical
933 * production configuration these hooks all should produce no code at all.
934 */
935static inline int slab_pre_alloc_hook(struct kmem_cache *s, gfp_t flags)
936{
c1d50836 937 flags &= gfp_allowed_mask;
c016b0bd
CL
938 lockdep_trace_alloc(flags);
939 might_sleep_if(flags & __GFP_WAIT);
940
941 return should_failslab(s->objsize, flags, s->flags);
942}
943
944static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags, void *object)
945{
c1d50836 946 flags &= gfp_allowed_mask;
b3d41885 947 kmemcheck_slab_alloc(s, flags, object, slab_ksize(s));
c016b0bd
CL
948 kmemleak_alloc_recursive(object, s->objsize, 1, s->flags, flags);
949}
950
951static inline void slab_free_hook(struct kmem_cache *s, void *x)
952{
953 kmemleak_free_recursive(x, s->flags);
c016b0bd 954
d3f661d6
CL
955 /*
956 * Trouble is that we may no longer disable interupts in the fast path
957 * So in order to make the debug calls that expect irqs to be
958 * disabled we need to disable interrupts temporarily.
959 */
960#if defined(CONFIG_KMEMCHECK) || defined(CONFIG_LOCKDEP)
961 {
962 unsigned long flags;
963
964 local_irq_save(flags);
965 kmemcheck_slab_free(s, x, s->objsize);
966 debug_check_no_locks_freed(x, s->objsize);
d3f661d6
CL
967 local_irq_restore(flags);
968 }
969#endif
f9b615de
TG
970 if (!(s->flags & SLAB_DEBUG_OBJECTS))
971 debug_check_no_obj_freed(x, s->objsize);
c016b0bd
CL
972}
973
643b1138 974/*
672bba3a 975 * Tracking of fully allocated slabs for debugging purposes.
5cc6eee8
CL
976 *
977 * list_lock must be held.
643b1138 978 */
5cc6eee8
CL
979static void add_full(struct kmem_cache *s,
980 struct kmem_cache_node *n, struct page *page)
643b1138 981{
5cc6eee8
CL
982 if (!(s->flags & SLAB_STORE_USER))
983 return;
984
643b1138 985 list_add(&page->lru, &n->full);
643b1138
CL
986}
987
5cc6eee8
CL
988/*
989 * list_lock must be held.
990 */
643b1138
CL
991static void remove_full(struct kmem_cache *s, struct page *page)
992{
643b1138
CL
993 if (!(s->flags & SLAB_STORE_USER))
994 return;
995
643b1138 996 list_del(&page->lru);
643b1138
CL
997}
998
0f389ec6
CL
999/* Tracking of the number of slabs for debugging purposes */
1000static inline unsigned long slabs_node(struct kmem_cache *s, int node)
1001{
1002 struct kmem_cache_node *n = get_node(s, node);
1003
1004 return atomic_long_read(&n->nr_slabs);
1005}
1006
26c02cf0
AB
1007static inline unsigned long node_nr_slabs(struct kmem_cache_node *n)
1008{
1009 return atomic_long_read(&n->nr_slabs);
1010}
1011
205ab99d 1012static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects)
0f389ec6
CL
1013{
1014 struct kmem_cache_node *n = get_node(s, node);
1015
1016 /*
1017 * May be called early in order to allocate a slab for the
1018 * kmem_cache_node structure. Solve the chicken-egg
1019 * dilemma by deferring the increment of the count during
1020 * bootstrap (see early_kmem_cache_node_alloc).
1021 */
7340cc84 1022 if (n) {
0f389ec6 1023 atomic_long_inc(&n->nr_slabs);
205ab99d
CL
1024 atomic_long_add(objects, &n->total_objects);
1025 }
0f389ec6 1026}
205ab99d 1027static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects)
0f389ec6
CL
1028{
1029 struct kmem_cache_node *n = get_node(s, node);
1030
1031 atomic_long_dec(&n->nr_slabs);
205ab99d 1032 atomic_long_sub(objects, &n->total_objects);
0f389ec6
CL
1033}
1034
1035/* Object debug checks for alloc/free paths */
3ec09742
CL
1036static void setup_object_debug(struct kmem_cache *s, struct page *page,
1037 void *object)
1038{
1039 if (!(s->flags & (SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON)))
1040 return;
1041
f7cb1933 1042 init_object(s, object, SLUB_RED_INACTIVE);
3ec09742
CL
1043 init_tracking(s, object);
1044}
1045
1537066c 1046static noinline int alloc_debug_processing(struct kmem_cache *s, struct page *page,
ce71e27c 1047 void *object, unsigned long addr)
81819f0f
CL
1048{
1049 if (!check_slab(s, page))
1050 goto bad;
1051
81819f0f
CL
1052 if (!check_valid_pointer(s, page, object)) {
1053 object_err(s, page, object, "Freelist Pointer check fails");
70d71228 1054 goto bad;
81819f0f
CL
1055 }
1056
f7cb1933 1057 if (!check_object(s, page, object, SLUB_RED_INACTIVE))
81819f0f 1058 goto bad;
81819f0f 1059
3ec09742
CL
1060 /* Success perform special debug activities for allocs */
1061 if (s->flags & SLAB_STORE_USER)
1062 set_track(s, object, TRACK_ALLOC, addr);
1063 trace(s, page, object, 1);
f7cb1933 1064 init_object(s, object, SLUB_RED_ACTIVE);
81819f0f 1065 return 1;
3ec09742 1066
81819f0f
CL
1067bad:
1068 if (PageSlab(page)) {
1069 /*
1070 * If this is a slab page then lets do the best we can
1071 * to avoid issues in the future. Marking all objects
672bba3a 1072 * as used avoids touching the remaining objects.
81819f0f 1073 */
24922684 1074 slab_fix(s, "Marking all objects used");
39b26464 1075 page->inuse = page->objects;
a973e9dd 1076 page->freelist = NULL;
81819f0f
CL
1077 }
1078 return 0;
1079}
1080
1537066c
CL
1081static noinline int free_debug_processing(struct kmem_cache *s,
1082 struct page *page, void *object, unsigned long addr)
81819f0f 1083{
5c2e4bbb
CL
1084 unsigned long flags;
1085 int rc = 0;
1086
1087 local_irq_save(flags);
881db7fb
CL
1088 slab_lock(page);
1089
81819f0f
CL
1090 if (!check_slab(s, page))
1091 goto fail;
1092
1093 if (!check_valid_pointer(s, page, object)) {
70d71228 1094 slab_err(s, page, "Invalid object pointer 0x%p", object);
81819f0f
CL
1095 goto fail;
1096 }
1097
1098 if (on_freelist(s, page, object)) {
24922684 1099 object_err(s, page, object, "Object already free");
81819f0f
CL
1100 goto fail;
1101 }
1102
f7cb1933 1103 if (!check_object(s, page, object, SLUB_RED_ACTIVE))
5c2e4bbb 1104 goto out;
81819f0f
CL
1105
1106 if (unlikely(s != page->slab)) {
3adbefee 1107 if (!PageSlab(page)) {
70d71228
CL
1108 slab_err(s, page, "Attempt to free object(0x%p) "
1109 "outside of slab", object);
3adbefee 1110 } else if (!page->slab) {
81819f0f 1111 printk(KERN_ERR
70d71228 1112 "SLUB <none>: no slab for object 0x%p.\n",
81819f0f 1113 object);
70d71228 1114 dump_stack();
06428780 1115 } else
24922684
CL
1116 object_err(s, page, object,
1117 "page slab pointer corrupt.");
81819f0f
CL
1118 goto fail;
1119 }
3ec09742 1120
3ec09742
CL
1121 if (s->flags & SLAB_STORE_USER)
1122 set_track(s, object, TRACK_FREE, addr);
1123 trace(s, page, object, 0);
f7cb1933 1124 init_object(s, object, SLUB_RED_INACTIVE);
5c2e4bbb
CL
1125 rc = 1;
1126out:
881db7fb 1127 slab_unlock(page);
5c2e4bbb
CL
1128 local_irq_restore(flags);
1129 return rc;
3ec09742 1130
81819f0f 1131fail:
24922684 1132 slab_fix(s, "Object at 0x%p not freed", object);
5c2e4bbb 1133 goto out;
81819f0f
CL
1134}
1135
41ecc55b
CL
1136static int __init setup_slub_debug(char *str)
1137{
f0630fff
CL
1138 slub_debug = DEBUG_DEFAULT_FLAGS;
1139 if (*str++ != '=' || !*str)
1140 /*
1141 * No options specified. Switch on full debugging.
1142 */
1143 goto out;
1144
1145 if (*str == ',')
1146 /*
1147 * No options but restriction on slabs. This means full
1148 * debugging for slabs matching a pattern.
1149 */
1150 goto check_slabs;
1151
fa5ec8a1
DR
1152 if (tolower(*str) == 'o') {
1153 /*
1154 * Avoid enabling debugging on caches if its minimum order
1155 * would increase as a result.
1156 */
1157 disable_higher_order_debug = 1;
1158 goto out;
1159 }
1160
f0630fff
CL
1161 slub_debug = 0;
1162 if (*str == '-')
1163 /*
1164 * Switch off all debugging measures.
1165 */
1166 goto out;
1167
1168 /*
1169 * Determine which debug features should be switched on
1170 */
06428780 1171 for (; *str && *str != ','; str++) {
f0630fff
CL
1172 switch (tolower(*str)) {
1173 case 'f':
1174 slub_debug |= SLAB_DEBUG_FREE;
1175 break;
1176 case 'z':
1177 slub_debug |= SLAB_RED_ZONE;
1178 break;
1179 case 'p':
1180 slub_debug |= SLAB_POISON;
1181 break;
1182 case 'u':
1183 slub_debug |= SLAB_STORE_USER;
1184 break;
1185 case 't':
1186 slub_debug |= SLAB_TRACE;
1187 break;
4c13dd3b
DM
1188 case 'a':
1189 slub_debug |= SLAB_FAILSLAB;
1190 break;
f0630fff
CL
1191 default:
1192 printk(KERN_ERR "slub_debug option '%c' "
06428780 1193 "unknown. skipped\n", *str);
f0630fff 1194 }
41ecc55b
CL
1195 }
1196
f0630fff 1197check_slabs:
41ecc55b
CL
1198 if (*str == ',')
1199 slub_debug_slabs = str + 1;
f0630fff 1200out:
41ecc55b
CL
1201 return 1;
1202}
1203
1204__setup("slub_debug", setup_slub_debug);
1205
ba0268a8
CL
1206static unsigned long kmem_cache_flags(unsigned long objsize,
1207 unsigned long flags, const char *name,
51cc5068 1208 void (*ctor)(void *))
41ecc55b
CL
1209{
1210 /*
e153362a 1211 * Enable debugging if selected on the kernel commandline.
41ecc55b 1212 */
e153362a 1213 if (slub_debug && (!slub_debug_slabs ||
3de47213
DR
1214 !strncmp(slub_debug_slabs, name, strlen(slub_debug_slabs))))
1215 flags |= slub_debug;
ba0268a8
CL
1216
1217 return flags;
41ecc55b
CL
1218}
1219#else
3ec09742
CL
1220static inline void setup_object_debug(struct kmem_cache *s,
1221 struct page *page, void *object) {}
41ecc55b 1222
3ec09742 1223static inline int alloc_debug_processing(struct kmem_cache *s,
ce71e27c 1224 struct page *page, void *object, unsigned long addr) { return 0; }
41ecc55b 1225
3ec09742 1226static inline int free_debug_processing(struct kmem_cache *s,
ce71e27c 1227 struct page *page, void *object, unsigned long addr) { return 0; }
41ecc55b 1228
41ecc55b
CL
1229static inline int slab_pad_check(struct kmem_cache *s, struct page *page)
1230 { return 1; }
1231static inline int check_object(struct kmem_cache *s, struct page *page,
f7cb1933 1232 void *object, u8 val) { return 1; }
5cc6eee8
CL
1233static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n,
1234 struct page *page) {}
2cfb7455 1235static inline void remove_full(struct kmem_cache *s, struct page *page) {}
ba0268a8
CL
1236static inline unsigned long kmem_cache_flags(unsigned long objsize,
1237 unsigned long flags, const char *name,
51cc5068 1238 void (*ctor)(void *))
ba0268a8
CL
1239{
1240 return flags;
1241}
41ecc55b 1242#define slub_debug 0
0f389ec6 1243
fdaa45e9
IM
1244#define disable_higher_order_debug 0
1245
0f389ec6
CL
1246static inline unsigned long slabs_node(struct kmem_cache *s, int node)
1247 { return 0; }
26c02cf0
AB
1248static inline unsigned long node_nr_slabs(struct kmem_cache_node *n)
1249 { return 0; }
205ab99d
CL
1250static inline void inc_slabs_node(struct kmem_cache *s, int node,
1251 int objects) {}
1252static inline void dec_slabs_node(struct kmem_cache *s, int node,
1253 int objects) {}
7d550c56
CL
1254
1255static inline int slab_pre_alloc_hook(struct kmem_cache *s, gfp_t flags)
1256 { return 0; }
1257
1258static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
1259 void *object) {}
1260
1261static inline void slab_free_hook(struct kmem_cache *s, void *x) {}
1262
ab4d5ed5 1263#endif /* CONFIG_SLUB_DEBUG */
205ab99d 1264
81819f0f
CL
1265/*
1266 * Slab allocation and freeing
1267 */
65c3376a
CL
1268static inline struct page *alloc_slab_page(gfp_t flags, int node,
1269 struct kmem_cache_order_objects oo)
1270{
1271 int order = oo_order(oo);
1272
b1eeab67
VN
1273 flags |= __GFP_NOTRACK;
1274
2154a336 1275 if (node == NUMA_NO_NODE)
65c3376a
CL
1276 return alloc_pages(flags, order);
1277 else
6b65aaf3 1278 return alloc_pages_exact_node(node, flags, order);
65c3376a
CL
1279}
1280
81819f0f
CL
1281static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
1282{
06428780 1283 struct page *page;
834f3d11 1284 struct kmem_cache_order_objects oo = s->oo;
ba52270d 1285 gfp_t alloc_gfp;
81819f0f 1286
7e0528da
CL
1287 flags &= gfp_allowed_mask;
1288
1289 if (flags & __GFP_WAIT)
1290 local_irq_enable();
1291
b7a49f0d 1292 flags |= s->allocflags;
e12ba74d 1293
ba52270d
PE
1294 /*
1295 * Let the initial higher-order allocation fail under memory pressure
1296 * so we fall-back to the minimum order allocation.
1297 */
1298 alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL;
1299
1300 page = alloc_slab_page(alloc_gfp, node, oo);
65c3376a
CL
1301 if (unlikely(!page)) {
1302 oo = s->min;
1303 /*
1304 * Allocation may have failed due to fragmentation.
1305 * Try a lower order alloc if possible
1306 */
1307 page = alloc_slab_page(flags, node, oo);
81819f0f 1308
7e0528da
CL
1309 if (page)
1310 stat(s, ORDER_FALLBACK);
65c3376a 1311 }
5a896d9e 1312
7e0528da
CL
1313 if (flags & __GFP_WAIT)
1314 local_irq_disable();
1315
1316 if (!page)
1317 return NULL;
1318
5a896d9e 1319 if (kmemcheck_enabled
5086c389 1320 && !(s->flags & (SLAB_NOTRACK | DEBUG_DEFAULT_FLAGS))) {
b1eeab67
VN
1321 int pages = 1 << oo_order(oo);
1322
1323 kmemcheck_alloc_shadow(page, oo_order(oo), flags, node);
1324
1325 /*
1326 * Objects from caches that have a constructor don't get
1327 * cleared when they're allocated, so we need to do it here.
1328 */
1329 if (s->ctor)
1330 kmemcheck_mark_uninitialized_pages(page, pages);
1331 else
1332 kmemcheck_mark_unallocated_pages(page, pages);
5a896d9e
VN
1333 }
1334
834f3d11 1335 page->objects = oo_objects(oo);
81819f0f
CL
1336 mod_zone_page_state(page_zone(page),
1337 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
1338 NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
65c3376a 1339 1 << oo_order(oo));
81819f0f
CL
1340
1341 return page;
1342}
1343
1344static void setup_object(struct kmem_cache *s, struct page *page,
1345 void *object)
1346{
3ec09742 1347 setup_object_debug(s, page, object);
4f104934 1348 if (unlikely(s->ctor))
51cc5068 1349 s->ctor(object);
81819f0f
CL
1350}
1351
1352static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
1353{
1354 struct page *page;
81819f0f 1355 void *start;
81819f0f
CL
1356 void *last;
1357 void *p;
1358
6cb06229 1359 BUG_ON(flags & GFP_SLAB_BUG_MASK);
81819f0f 1360
6cb06229
CL
1361 page = allocate_slab(s,
1362 flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node);
81819f0f
CL
1363 if (!page)
1364 goto out;
1365
205ab99d 1366 inc_slabs_node(s, page_to_nid(page), page->objects);
81819f0f
CL
1367 page->slab = s;
1368 page->flags |= 1 << PG_slab;
81819f0f
CL
1369
1370 start = page_address(page);
81819f0f
CL
1371
1372 if (unlikely(s->flags & SLAB_POISON))
834f3d11 1373 memset(start, POISON_INUSE, PAGE_SIZE << compound_order(page));
81819f0f
CL
1374
1375 last = start;
224a88be 1376 for_each_object(p, s, start, page->objects) {
81819f0f
CL
1377 setup_object(s, page, last);
1378 set_freepointer(s, last, p);
1379 last = p;
1380 }
1381 setup_object(s, page, last);
a973e9dd 1382 set_freepointer(s, last, NULL);
81819f0f
CL
1383
1384 page->freelist = start;
1385 page->inuse = 0;
8cb0a506 1386 page->frozen = 1;
81819f0f 1387out:
81819f0f
CL
1388 return page;
1389}
1390
1391static void __free_slab(struct kmem_cache *s, struct page *page)
1392{
834f3d11
CL
1393 int order = compound_order(page);
1394 int pages = 1 << order;
81819f0f 1395
af537b0a 1396 if (kmem_cache_debug(s)) {
81819f0f
CL
1397 void *p;
1398
1399 slab_pad_check(s, page);
224a88be
CL
1400 for_each_object(p, s, page_address(page),
1401 page->objects)
f7cb1933 1402 check_object(s, page, p, SLUB_RED_INACTIVE);
81819f0f
CL
1403 }
1404
b1eeab67 1405 kmemcheck_free_shadow(page, compound_order(page));
5a896d9e 1406
81819f0f
CL
1407 mod_zone_page_state(page_zone(page),
1408 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
1409 NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
06428780 1410 -pages);
81819f0f 1411
49bd5221
CL
1412 __ClearPageSlab(page);
1413 reset_page_mapcount(page);
1eb5ac64
NP
1414 if (current->reclaim_state)
1415 current->reclaim_state->reclaimed_slab += pages;
834f3d11 1416 __free_pages(page, order);
81819f0f
CL
1417}
1418
da9a638c
LJ
1419#define need_reserve_slab_rcu \
1420 (sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head))
1421
81819f0f
CL
1422static void rcu_free_slab(struct rcu_head *h)
1423{
1424 struct page *page;
1425
da9a638c
LJ
1426 if (need_reserve_slab_rcu)
1427 page = virt_to_head_page(h);
1428 else
1429 page = container_of((struct list_head *)h, struct page, lru);
1430
81819f0f
CL
1431 __free_slab(page->slab, page);
1432}
1433
1434static void free_slab(struct kmem_cache *s, struct page *page)
1435{
1436 if (unlikely(s->flags & SLAB_DESTROY_BY_RCU)) {
da9a638c
LJ
1437 struct rcu_head *head;
1438
1439 if (need_reserve_slab_rcu) {
1440 int order = compound_order(page);
1441 int offset = (PAGE_SIZE << order) - s->reserved;
1442
1443 VM_BUG_ON(s->reserved != sizeof(*head));
1444 head = page_address(page) + offset;
1445 } else {
1446 /*
1447 * RCU free overloads the RCU head over the LRU
1448 */
1449 head = (void *)&page->lru;
1450 }
81819f0f
CL
1451
1452 call_rcu(head, rcu_free_slab);
1453 } else
1454 __free_slab(s, page);
1455}
1456
1457static void discard_slab(struct kmem_cache *s, struct page *page)
1458{
205ab99d 1459 dec_slabs_node(s, page_to_nid(page), page->objects);
81819f0f
CL
1460 free_slab(s, page);
1461}
1462
81819f0f 1463/*
5cc6eee8
CL
1464 * Management of partially allocated slabs.
1465 *
1466 * list_lock must be held.
81819f0f 1467 */
5cc6eee8 1468static inline void add_partial(struct kmem_cache_node *n,
7c2e132c 1469 struct page *page, int tail)
81819f0f 1470{
e95eed57 1471 n->nr_partial++;
7c2e132c
CL
1472 if (tail)
1473 list_add_tail(&page->lru, &n->partial);
1474 else
1475 list_add(&page->lru, &n->partial);
81819f0f
CL
1476}
1477
5cc6eee8
CL
1478/*
1479 * list_lock must be held.
1480 */
1481static inline void remove_partial(struct kmem_cache_node *n,
62e346a8
CL
1482 struct page *page)
1483{
1484 list_del(&page->lru);
1485 n->nr_partial--;
1486}
1487
81819f0f 1488/*
5cc6eee8
CL
1489 * Lock slab, remove from the partial list and put the object into the
1490 * per cpu freelist.
81819f0f 1491 *
672bba3a 1492 * Must hold list_lock.
81819f0f 1493 */
881db7fb 1494static inline int acquire_slab(struct kmem_cache *s,
61728d1e 1495 struct kmem_cache_node *n, struct page *page)
81819f0f 1496{
2cfb7455
CL
1497 void *freelist;
1498 unsigned long counters;
1499 struct page new;
1500
2cfb7455
CL
1501 /*
1502 * Zap the freelist and set the frozen bit.
1503 * The old freelist is the list of objects for the
1504 * per cpu allocation list.
1505 */
1506 do {
1507 freelist = page->freelist;
1508 counters = page->counters;
1509 new.counters = counters;
1510 new.inuse = page->objects;
1511
1512 VM_BUG_ON(new.frozen);
1513 new.frozen = 1;
1514
1d07171c 1515 } while (!__cmpxchg_double_slab(s, page,
2cfb7455
CL
1516 freelist, counters,
1517 NULL, new.counters,
1518 "lock and freeze"));
1519
1520 remove_partial(n, page);
1521
1522 if (freelist) {
1523 /* Populate the per cpu freelist */
1524 this_cpu_write(s->cpu_slab->freelist, freelist);
1525 this_cpu_write(s->cpu_slab->page, page);
1526 this_cpu_write(s->cpu_slab->node, page_to_nid(page));
81819f0f 1527 return 1;
2cfb7455
CL
1528 } else {
1529 /*
1530 * Slab page came from the wrong list. No object to allocate
1531 * from. Put it onto the correct list and continue partial
1532 * scan.
1533 */
1534 printk(KERN_ERR "SLUB: %s : Page without available objects on"
1535 " partial list\n", s->name);
2cfb7455 1536 return 0;
81819f0f 1537 }
81819f0f
CL
1538}
1539
1540/*
672bba3a 1541 * Try to allocate a partial slab from a specific node.
81819f0f 1542 */
61728d1e
CL
1543static struct page *get_partial_node(struct kmem_cache *s,
1544 struct kmem_cache_node *n)
81819f0f
CL
1545{
1546 struct page *page;
1547
1548 /*
1549 * Racy check. If we mistakenly see no partial slabs then we
1550 * just allocate an empty slab. If we mistakenly try to get a
672bba3a
CL
1551 * partial slab and there is none available then get_partials()
1552 * will return NULL.
81819f0f
CL
1553 */
1554 if (!n || !n->nr_partial)
1555 return NULL;
1556
1557 spin_lock(&n->list_lock);
1558 list_for_each_entry(page, &n->partial, lru)
881db7fb 1559 if (acquire_slab(s, n, page))
81819f0f
CL
1560 goto out;
1561 page = NULL;
1562out:
1563 spin_unlock(&n->list_lock);
1564 return page;
1565}
1566
1567/*
672bba3a 1568 * Get a page from somewhere. Search in increasing NUMA distances.
81819f0f
CL
1569 */
1570static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags)
1571{
1572#ifdef CONFIG_NUMA
1573 struct zonelist *zonelist;
dd1a239f 1574 struct zoneref *z;
54a6eb5c
MG
1575 struct zone *zone;
1576 enum zone_type high_zoneidx = gfp_zone(flags);
81819f0f
CL
1577 struct page *page;
1578
1579 /*
672bba3a
CL
1580 * The defrag ratio allows a configuration of the tradeoffs between
1581 * inter node defragmentation and node local allocations. A lower
1582 * defrag_ratio increases the tendency to do local allocations
1583 * instead of attempting to obtain partial slabs from other nodes.
81819f0f 1584 *
672bba3a
CL
1585 * If the defrag_ratio is set to 0 then kmalloc() always
1586 * returns node local objects. If the ratio is higher then kmalloc()
1587 * may return off node objects because partial slabs are obtained
1588 * from other nodes and filled up.
81819f0f 1589 *
6446faa2 1590 * If /sys/kernel/slab/xx/defrag_ratio is set to 100 (which makes
672bba3a
CL
1591 * defrag_ratio = 1000) then every (well almost) allocation will
1592 * first attempt to defrag slab caches on other nodes. This means
1593 * scanning over all nodes to look for partial slabs which may be
1594 * expensive if we do it every time we are trying to find a slab
1595 * with available objects.
81819f0f 1596 */
9824601e
CL
1597 if (!s->remote_node_defrag_ratio ||
1598 get_cycles() % 1024 > s->remote_node_defrag_ratio)
81819f0f
CL
1599 return NULL;
1600
c0ff7453 1601 get_mems_allowed();
0e88460d 1602 zonelist = node_zonelist(slab_node(current->mempolicy), flags);
54a6eb5c 1603 for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
81819f0f
CL
1604 struct kmem_cache_node *n;
1605
54a6eb5c 1606 n = get_node(s, zone_to_nid(zone));
81819f0f 1607
54a6eb5c 1608 if (n && cpuset_zone_allowed_hardwall(zone, flags) &&
3b89d7d8 1609 n->nr_partial > s->min_partial) {
61728d1e 1610 page = get_partial_node(s, n);
c0ff7453
MX
1611 if (page) {
1612 put_mems_allowed();
81819f0f 1613 return page;
c0ff7453 1614 }
81819f0f
CL
1615 }
1616 }
c0ff7453 1617 put_mems_allowed();
81819f0f
CL
1618#endif
1619 return NULL;
1620}
1621
1622/*
1623 * Get a partial page, lock it and return it.
1624 */
1625static struct page *get_partial(struct kmem_cache *s, gfp_t flags, int node)
1626{
1627 struct page *page;
2154a336 1628 int searchnode = (node == NUMA_NO_NODE) ? numa_node_id() : node;
81819f0f 1629
61728d1e 1630 page = get_partial_node(s, get_node(s, searchnode));
33de04ec 1631 if (page || node != NUMA_NO_NODE)
81819f0f
CL
1632 return page;
1633
1634 return get_any_partial(s, flags);
1635}
1636
8a5ec0ba
CL
1637#ifdef CONFIG_PREEMPT
1638/*
1639 * Calculate the next globally unique transaction for disambiguiation
1640 * during cmpxchg. The transactions start with the cpu number and are then
1641 * incremented by CONFIG_NR_CPUS.
1642 */
1643#define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS)
1644#else
1645/*
1646 * No preemption supported therefore also no need to check for
1647 * different cpus.
1648 */
1649#define TID_STEP 1
1650#endif
1651
1652static inline unsigned long next_tid(unsigned long tid)
1653{
1654 return tid + TID_STEP;
1655}
1656
1657static inline unsigned int tid_to_cpu(unsigned long tid)
1658{
1659 return tid % TID_STEP;
1660}
1661
1662static inline unsigned long tid_to_event(unsigned long tid)
1663{
1664 return tid / TID_STEP;
1665}
1666
1667static inline unsigned int init_tid(int cpu)
1668{
1669 return cpu;
1670}
1671
1672static inline void note_cmpxchg_failure(const char *n,
1673 const struct kmem_cache *s, unsigned long tid)
1674{
1675#ifdef SLUB_DEBUG_CMPXCHG
1676 unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid);
1677
1678 printk(KERN_INFO "%s %s: cmpxchg redo ", n, s->name);
1679
1680#ifdef CONFIG_PREEMPT
1681 if (tid_to_cpu(tid) != tid_to_cpu(actual_tid))
1682 printk("due to cpu change %d -> %d\n",
1683 tid_to_cpu(tid), tid_to_cpu(actual_tid));
1684 else
1685#endif
1686 if (tid_to_event(tid) != tid_to_event(actual_tid))
1687 printk("due to cpu running other code. Event %ld->%ld\n",
1688 tid_to_event(tid), tid_to_event(actual_tid));
1689 else
1690 printk("for unknown reason: actual=%lx was=%lx target=%lx\n",
1691 actual_tid, tid, next_tid(tid));
1692#endif
4fdccdfb 1693 stat(s, CMPXCHG_DOUBLE_CPU_FAIL);
8a5ec0ba
CL
1694}
1695
8a5ec0ba
CL
1696void init_kmem_cache_cpus(struct kmem_cache *s)
1697{
8a5ec0ba
CL
1698 int cpu;
1699
1700 for_each_possible_cpu(cpu)
1701 per_cpu_ptr(s->cpu_slab, cpu)->tid = init_tid(cpu);
8a5ec0ba 1702}
2cfb7455
CL
1703/*
1704 * Remove the cpu slab
1705 */
1706
81819f0f
CL
1707/*
1708 * Remove the cpu slab
1709 */
dfb4f096 1710static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
81819f0f 1711{
2cfb7455 1712 enum slab_modes { M_NONE, M_PARTIAL, M_FULL, M_FREE };
dfb4f096 1713 struct page *page = c->page;
2cfb7455
CL
1714 struct kmem_cache_node *n = get_node(s, page_to_nid(page));
1715 int lock = 0;
1716 enum slab_modes l = M_NONE, m = M_NONE;
1717 void *freelist;
1718 void *nextfree;
1719 int tail = 0;
1720 struct page new;
1721 struct page old;
1722
1723 if (page->freelist) {
84e554e6 1724 stat(s, DEACTIVATE_REMOTE_FREES);
2cfb7455
CL
1725 tail = 1;
1726 }
1727
1728 c->tid = next_tid(c->tid);
1729 c->page = NULL;
1730 freelist = c->freelist;
1731 c->freelist = NULL;
1732
894b8788 1733 /*
2cfb7455
CL
1734 * Stage one: Free all available per cpu objects back
1735 * to the page freelist while it is still frozen. Leave the
1736 * last one.
1737 *
1738 * There is no need to take the list->lock because the page
1739 * is still frozen.
1740 */
1741 while (freelist && (nextfree = get_freepointer(s, freelist))) {
1742 void *prior;
1743 unsigned long counters;
1744
1745 do {
1746 prior = page->freelist;
1747 counters = page->counters;
1748 set_freepointer(s, freelist, prior);
1749 new.counters = counters;
1750 new.inuse--;
1751 VM_BUG_ON(!new.frozen);
1752
1d07171c 1753 } while (!__cmpxchg_double_slab(s, page,
2cfb7455
CL
1754 prior, counters,
1755 freelist, new.counters,
1756 "drain percpu freelist"));
1757
1758 freelist = nextfree;
1759 }
1760
1761 /*
1762 * Stage two: Ensure that the page is unfrozen while the
1763 * list presence reflects the actual number of objects
1764 * during unfreeze.
1765 *
1766 * We setup the list membership and then perform a cmpxchg
1767 * with the count. If there is a mismatch then the page
1768 * is not unfrozen but the page is on the wrong list.
1769 *
1770 * Then we restart the process which may have to remove
1771 * the page from the list that we just put it on again
1772 * because the number of objects in the slab may have
1773 * changed.
894b8788 1774 */
2cfb7455 1775redo:
894b8788 1776
2cfb7455
CL
1777 old.freelist = page->freelist;
1778 old.counters = page->counters;
1779 VM_BUG_ON(!old.frozen);
7c2e132c 1780
2cfb7455
CL
1781 /* Determine target state of the slab */
1782 new.counters = old.counters;
1783 if (freelist) {
1784 new.inuse--;
1785 set_freepointer(s, freelist, old.freelist);
1786 new.freelist = freelist;
1787 } else
1788 new.freelist = old.freelist;
1789
1790 new.frozen = 0;
1791
1792 if (!new.inuse && n->nr_partial < s->min_partial)
1793 m = M_FREE;
1794 else if (new.freelist) {
1795 m = M_PARTIAL;
1796 if (!lock) {
1797 lock = 1;
1798 /*
1799 * Taking the spinlock removes the possiblity
1800 * that acquire_slab() will see a slab page that
1801 * is frozen
1802 */
1803 spin_lock(&n->list_lock);
1804 }
1805 } else {
1806 m = M_FULL;
1807 if (kmem_cache_debug(s) && !lock) {
1808 lock = 1;
1809 /*
1810 * This also ensures that the scanning of full
1811 * slabs from diagnostic functions will not see
1812 * any frozen slabs.
1813 */
1814 spin_lock(&n->list_lock);
1815 }
1816 }
1817
1818 if (l != m) {
1819
1820 if (l == M_PARTIAL)
1821
1822 remove_partial(n, page);
1823
1824 else if (l == M_FULL)
894b8788 1825
2cfb7455
CL
1826 remove_full(s, page);
1827
1828 if (m == M_PARTIAL) {
1829
1830 add_partial(n, page, tail);
1831 stat(s, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD);
1832
1833 } else if (m == M_FULL) {
1834
1835 stat(s, DEACTIVATE_FULL);
1836 add_full(s, n, page);
1837
1838 }
1839 }
1840
1841 l = m;
1d07171c 1842 if (!__cmpxchg_double_slab(s, page,
2cfb7455
CL
1843 old.freelist, old.counters,
1844 new.freelist, new.counters,
1845 "unfreezing slab"))
1846 goto redo;
1847
2cfb7455
CL
1848 if (lock)
1849 spin_unlock(&n->list_lock);
1850
1851 if (m == M_FREE) {
1852 stat(s, DEACTIVATE_EMPTY);
1853 discard_slab(s, page);
1854 stat(s, FREE_SLAB);
894b8788 1855 }
81819f0f
CL
1856}
1857
dfb4f096 1858static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
81819f0f 1859{
84e554e6 1860 stat(s, CPUSLAB_FLUSH);
dfb4f096 1861 deactivate_slab(s, c);
81819f0f
CL
1862}
1863
1864/*
1865 * Flush cpu slab.
6446faa2 1866 *
81819f0f
CL
1867 * Called from IPI handler with interrupts disabled.
1868 */
0c710013 1869static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu)
81819f0f 1870{
9dfc6e68 1871 struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
81819f0f 1872
dfb4f096
CL
1873 if (likely(c && c->page))
1874 flush_slab(s, c);
81819f0f
CL
1875}
1876
1877static void flush_cpu_slab(void *d)
1878{
1879 struct kmem_cache *s = d;
81819f0f 1880
dfb4f096 1881 __flush_cpu_slab(s, smp_processor_id());
81819f0f
CL
1882}
1883
1884static void flush_all(struct kmem_cache *s)
1885{
15c8b6c1 1886 on_each_cpu(flush_cpu_slab, s, 1);
81819f0f
CL
1887}
1888
dfb4f096
CL
1889/*
1890 * Check if the objects in a per cpu structure fit numa
1891 * locality expectations.
1892 */
1893static inline int node_match(struct kmem_cache_cpu *c, int node)
1894{
1895#ifdef CONFIG_NUMA
2154a336 1896 if (node != NUMA_NO_NODE && c->node != node)
dfb4f096
CL
1897 return 0;
1898#endif
1899 return 1;
1900}
1901
781b2ba6
PE
1902static int count_free(struct page *page)
1903{
1904 return page->objects - page->inuse;
1905}
1906
1907static unsigned long count_partial(struct kmem_cache_node *n,
1908 int (*get_count)(struct page *))
1909{
1910 unsigned long flags;
1911 unsigned long x = 0;
1912 struct page *page;
1913
1914 spin_lock_irqsave(&n->list_lock, flags);
1915 list_for_each_entry(page, &n->partial, lru)
1916 x += get_count(page);
1917 spin_unlock_irqrestore(&n->list_lock, flags);
1918 return x;
1919}
1920
26c02cf0
AB
1921static inline unsigned long node_nr_objs(struct kmem_cache_node *n)
1922{
1923#ifdef CONFIG_SLUB_DEBUG
1924 return atomic_long_read(&n->total_objects);
1925#else
1926 return 0;
1927#endif
1928}
1929
781b2ba6
PE
1930static noinline void
1931slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid)
1932{
1933 int node;
1934
1935 printk(KERN_WARNING
1936 "SLUB: Unable to allocate memory on node %d (gfp=0x%x)\n",
1937 nid, gfpflags);
1938 printk(KERN_WARNING " cache: %s, object size: %d, buffer size: %d, "
1939 "default order: %d, min order: %d\n", s->name, s->objsize,
1940 s->size, oo_order(s->oo), oo_order(s->min));
1941
fa5ec8a1
DR
1942 if (oo_order(s->min) > get_order(s->objsize))
1943 printk(KERN_WARNING " %s debugging increased min order, use "
1944 "slub_debug=O to disable.\n", s->name);
1945
781b2ba6
PE
1946 for_each_online_node(node) {
1947 struct kmem_cache_node *n = get_node(s, node);
1948 unsigned long nr_slabs;
1949 unsigned long nr_objs;
1950 unsigned long nr_free;
1951
1952 if (!n)
1953 continue;
1954
26c02cf0
AB
1955 nr_free = count_partial(n, count_free);
1956 nr_slabs = node_nr_slabs(n);
1957 nr_objs = node_nr_objs(n);
781b2ba6
PE
1958
1959 printk(KERN_WARNING
1960 " node %d: slabs: %ld, objs: %ld, free: %ld\n",
1961 node, nr_slabs, nr_objs, nr_free);
1962 }
1963}
1964
81819f0f 1965/*
894b8788
CL
1966 * Slow path. The lockless freelist is empty or we need to perform
1967 * debugging duties.
1968 *
1969 * Interrupts are disabled.
81819f0f 1970 *
894b8788
CL
1971 * Processing is still very fast if new objects have been freed to the
1972 * regular freelist. In that case we simply take over the regular freelist
1973 * as the lockless freelist and zap the regular freelist.
81819f0f 1974 *
894b8788
CL
1975 * If that is not working then we fall back to the partial lists. We take the
1976 * first element of the freelist as the object to allocate now and move the
1977 * rest of the freelist to the lockless freelist.
81819f0f 1978 *
894b8788 1979 * And if we were unable to get a new slab from the partial slab lists then
6446faa2
CL
1980 * we need to allocate a new slab. This is the slowest path since it involves
1981 * a call to the page allocator and the setup of a new slab.
81819f0f 1982 */
ce71e27c
EGM
1983static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
1984 unsigned long addr, struct kmem_cache_cpu *c)
81819f0f 1985{
81819f0f 1986 void **object;
01ad8a7b 1987 struct page *page;
8a5ec0ba 1988 unsigned long flags;
2cfb7455
CL
1989 struct page new;
1990 unsigned long counters;
8a5ec0ba
CL
1991
1992 local_irq_save(flags);
1993#ifdef CONFIG_PREEMPT
1994 /*
1995 * We may have been preempted and rescheduled on a different
1996 * cpu before disabling interrupts. Need to reload cpu area
1997 * pointer.
1998 */
1999 c = this_cpu_ptr(s->cpu_slab);
8a5ec0ba 2000#endif
81819f0f 2001
e72e9c23
LT
2002 /* We handle __GFP_ZERO in the caller */
2003 gfpflags &= ~__GFP_ZERO;
2004
01ad8a7b
CL
2005 page = c->page;
2006 if (!page)
81819f0f
CL
2007 goto new_slab;
2008
fc59c053 2009 if (unlikely(!node_match(c, node))) {
e36a2652 2010 stat(s, ALLOC_NODE_MISMATCH);
fc59c053
CL
2011 deactivate_slab(s, c);
2012 goto new_slab;
2013 }
6446faa2 2014
2cfb7455
CL
2015 stat(s, ALLOC_SLOWPATH);
2016
2017 do {
2018 object = page->freelist;
2019 counters = page->counters;
2020 new.counters = counters;
2cfb7455
CL
2021 VM_BUG_ON(!new.frozen);
2022
03e404af
CL
2023 /*
2024 * If there is no object left then we use this loop to
2025 * deactivate the slab which is simple since no objects
2026 * are left in the slab and therefore we do not need to
2027 * put the page back onto the partial list.
2028 *
2029 * If there are objects left then we retrieve them
2030 * and use them to refill the per cpu queue.
2031 */
2032
2033 new.inuse = page->objects;
2034 new.frozen = object != NULL;
2035
1d07171c 2036 } while (!__cmpxchg_double_slab(s, page,
2cfb7455
CL
2037 object, counters,
2038 NULL, new.counters,
2039 "__slab_alloc"));
6446faa2 2040
03e404af
CL
2041 if (unlikely(!object)) {
2042 c->page = NULL;
2043 stat(s, DEACTIVATE_BYPASS);
fc59c053 2044 goto new_slab;
03e404af 2045 }
81819f0f 2046
2cfb7455 2047 stat(s, ALLOC_REFILL);
01ad8a7b 2048
4eade540
CL
2049load_freelist:
2050 VM_BUG_ON(!page->frozen);
2cfb7455 2051 c->freelist = get_freepointer(s, object);
8a5ec0ba
CL
2052 c->tid = next_tid(c->tid);
2053 local_irq_restore(flags);
81819f0f
CL
2054 return object;
2055
81819f0f 2056new_slab:
01ad8a7b
CL
2057 page = get_partial(s, gfpflags, node);
2058 if (page) {
84e554e6 2059 stat(s, ALLOC_FROM_PARTIAL);
2cfb7455
CL
2060 object = c->freelist;
2061
2062 if (kmem_cache_debug(s))
2063 goto debug;
894b8788 2064 goto load_freelist;
81819f0f
CL
2065 }
2066
01ad8a7b 2067 page = new_slab(s, gfpflags, node);
b811c202 2068
01ad8a7b 2069 if (page) {
9dfc6e68 2070 c = __this_cpu_ptr(s->cpu_slab);
05aa3450 2071 if (c->page)
dfb4f096 2072 flush_slab(s, c);
01ad8a7b 2073
2cfb7455
CL
2074 /*
2075 * No other reference to the page yet so we can
2076 * muck around with it freely without cmpxchg
2077 */
2078 object = page->freelist;
2079 page->freelist = NULL;
2080 page->inuse = page->objects;
2081
2082 stat(s, ALLOC_SLAB);
bd07d87f
DR
2083 c->node = page_to_nid(page);
2084 c->page = page;
9e577e8b
CL
2085
2086 if (kmem_cache_debug(s))
2087 goto debug;
4b6f0750 2088 goto load_freelist;
81819f0f 2089 }
95f85989
PE
2090 if (!(gfpflags & __GFP_NOWARN) && printk_ratelimit())
2091 slab_out_of_memory(s, gfpflags, node);
2fd66c51 2092 local_irq_restore(flags);
71c7a06f 2093 return NULL;
2cfb7455 2094
81819f0f 2095debug:
2cfb7455
CL
2096 if (!object || !alloc_debug_processing(s, page, object, addr))
2097 goto new_slab;
894b8788 2098
2cfb7455 2099 c->freelist = get_freepointer(s, object);
442b06bc
CL
2100 deactivate_slab(s, c);
2101 c->page = NULL;
15b7c514 2102 c->node = NUMA_NO_NODE;
a71ae47a
CL
2103 local_irq_restore(flags);
2104 return object;
894b8788
CL
2105}
2106
2107/*
2108 * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc)
2109 * have the fastpath folded into their functions. So no function call
2110 * overhead for requests that can be satisfied on the fastpath.
2111 *
2112 * The fastpath works by first checking if the lockless freelist can be used.
2113 * If not then __slab_alloc is called for slow processing.
2114 *
2115 * Otherwise we can simply pick the next object from the lockless free list.
2116 */
06428780 2117static __always_inline void *slab_alloc(struct kmem_cache *s,
ce71e27c 2118 gfp_t gfpflags, int node, unsigned long addr)
894b8788 2119{
894b8788 2120 void **object;
dfb4f096 2121 struct kmem_cache_cpu *c;
8a5ec0ba 2122 unsigned long tid;
1f84260c 2123
c016b0bd 2124 if (slab_pre_alloc_hook(s, gfpflags))
773ff60e 2125 return NULL;
1f84260c 2126
8a5ec0ba 2127redo:
8a5ec0ba
CL
2128
2129 /*
2130 * Must read kmem_cache cpu data via this cpu ptr. Preemption is
2131 * enabled. We may switch back and forth between cpus while
2132 * reading from one cpu area. That does not matter as long
2133 * as we end up on the original cpu again when doing the cmpxchg.
2134 */
9dfc6e68 2135 c = __this_cpu_ptr(s->cpu_slab);
8a5ec0ba 2136
8a5ec0ba
CL
2137 /*
2138 * The transaction ids are globally unique per cpu and per operation on
2139 * a per cpu queue. Thus they can be guarantee that the cmpxchg_double
2140 * occurs on the right processor and that there was no operation on the
2141 * linked list in between.
2142 */
2143 tid = c->tid;
2144 barrier();
8a5ec0ba 2145
9dfc6e68 2146 object = c->freelist;
9dfc6e68 2147 if (unlikely(!object || !node_match(c, node)))
894b8788 2148
dfb4f096 2149 object = __slab_alloc(s, gfpflags, node, addr, c);
894b8788
CL
2150
2151 else {
8a5ec0ba 2152 /*
25985edc 2153 * The cmpxchg will only match if there was no additional
8a5ec0ba
CL
2154 * operation and if we are on the right processor.
2155 *
2156 * The cmpxchg does the following atomically (without lock semantics!)
2157 * 1. Relocate first pointer to the current per cpu area.
2158 * 2. Verify that tid and freelist have not been changed
2159 * 3. If they were not changed replace tid and freelist
2160 *
2161 * Since this is without lock semantics the protection is only against
2162 * code executing on this cpu *not* from access by other cpus.
2163 */
30106b8c 2164 if (unlikely(!irqsafe_cpu_cmpxchg_double(
8a5ec0ba
CL
2165 s->cpu_slab->freelist, s->cpu_slab->tid,
2166 object, tid,
1393d9a1 2167 get_freepointer_safe(s, object), next_tid(tid)))) {
8a5ec0ba
CL
2168
2169 note_cmpxchg_failure("slab_alloc", s, tid);
2170 goto redo;
2171 }
84e554e6 2172 stat(s, ALLOC_FASTPATH);
894b8788 2173 }
8a5ec0ba 2174
74e2134f 2175 if (unlikely(gfpflags & __GFP_ZERO) && object)
ff12059e 2176 memset(object, 0, s->objsize);
d07dbea4 2177
c016b0bd 2178 slab_post_alloc_hook(s, gfpflags, object);
5a896d9e 2179
894b8788 2180 return object;
81819f0f
CL
2181}
2182
2183void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags)
2184{
2154a336 2185 void *ret = slab_alloc(s, gfpflags, NUMA_NO_NODE, _RET_IP_);
5b882be4 2186
ca2b84cb 2187 trace_kmem_cache_alloc(_RET_IP_, ret, s->objsize, s->size, gfpflags);
5b882be4
EGM
2188
2189 return ret;
81819f0f
CL
2190}
2191EXPORT_SYMBOL(kmem_cache_alloc);
2192
0f24f128 2193#ifdef CONFIG_TRACING
4a92379b
RK
2194void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size)
2195{
2196 void *ret = slab_alloc(s, gfpflags, NUMA_NO_NODE, _RET_IP_);
2197 trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags);
2198 return ret;
2199}
2200EXPORT_SYMBOL(kmem_cache_alloc_trace);
2201
2202void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
5b882be4 2203{
4a92379b
RK
2204 void *ret = kmalloc_order(size, flags, order);
2205 trace_kmalloc(_RET_IP_, ret, size, PAGE_SIZE << order, flags);
2206 return ret;
5b882be4 2207}
4a92379b 2208EXPORT_SYMBOL(kmalloc_order_trace);
5b882be4
EGM
2209#endif
2210
81819f0f
CL
2211#ifdef CONFIG_NUMA
2212void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node)
2213{
5b882be4
EGM
2214 void *ret = slab_alloc(s, gfpflags, node, _RET_IP_);
2215
ca2b84cb
EGM
2216 trace_kmem_cache_alloc_node(_RET_IP_, ret,
2217 s->objsize, s->size, gfpflags, node);
5b882be4
EGM
2218
2219 return ret;
81819f0f
CL
2220}
2221EXPORT_SYMBOL(kmem_cache_alloc_node);
81819f0f 2222
0f24f128 2223#ifdef CONFIG_TRACING
4a92379b 2224void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
5b882be4 2225 gfp_t gfpflags,
4a92379b 2226 int node, size_t size)
5b882be4 2227{
4a92379b
RK
2228 void *ret = slab_alloc(s, gfpflags, node, _RET_IP_);
2229
2230 trace_kmalloc_node(_RET_IP_, ret,
2231 size, s->size, gfpflags, node);
2232 return ret;
5b882be4 2233}
4a92379b 2234EXPORT_SYMBOL(kmem_cache_alloc_node_trace);
5b882be4 2235#endif
5d1f57e4 2236#endif
5b882be4 2237
81819f0f 2238/*
894b8788
CL
2239 * Slow patch handling. This may still be called frequently since objects
2240 * have a longer lifetime than the cpu slabs in most processing loads.
81819f0f 2241 *
894b8788
CL
2242 * So we still attempt to reduce cache line usage. Just take the slab
2243 * lock and free the item. If there is no additional partial page
2244 * handling required then we can return immediately.
81819f0f 2245 */
894b8788 2246static void __slab_free(struct kmem_cache *s, struct page *page,
ff12059e 2247 void *x, unsigned long addr)
81819f0f
CL
2248{
2249 void *prior;
2250 void **object = (void *)x;
2cfb7455
CL
2251 int was_frozen;
2252 int inuse;
2253 struct page new;
2254 unsigned long counters;
2255 struct kmem_cache_node *n = NULL;
61728d1e 2256 unsigned long uninitialized_var(flags);
81819f0f 2257
8a5ec0ba 2258 stat(s, FREE_SLOWPATH);
81819f0f 2259
8dc16c6c 2260 if (kmem_cache_debug(s) && !free_debug_processing(s, page, x, addr))
80f08c19 2261 return;
6446faa2 2262
2cfb7455
CL
2263 do {
2264 prior = page->freelist;
2265 counters = page->counters;
2266 set_freepointer(s, object, prior);
2267 new.counters = counters;
2268 was_frozen = new.frozen;
2269 new.inuse--;
2270 if ((!new.inuse || !prior) && !was_frozen && !n) {
2271 n = get_node(s, page_to_nid(page));
2272 /*
2273 * Speculatively acquire the list_lock.
2274 * If the cmpxchg does not succeed then we may
2275 * drop the list_lock without any processing.
2276 *
2277 * Otherwise the list_lock will synchronize with
2278 * other processors updating the list of slabs.
2279 */
80f08c19 2280 spin_lock_irqsave(&n->list_lock, flags);
2cfb7455
CL
2281 }
2282 inuse = new.inuse;
81819f0f 2283
2cfb7455
CL
2284 } while (!cmpxchg_double_slab(s, page,
2285 prior, counters,
2286 object, new.counters,
2287 "__slab_free"));
81819f0f 2288
2cfb7455
CL
2289 if (likely(!n)) {
2290 /*
2291 * The list lock was not taken therefore no list
2292 * activity can be necessary.
2293 */
2294 if (was_frozen)
2295 stat(s, FREE_FROZEN);
80f08c19 2296 return;
2cfb7455 2297 }
81819f0f
CL
2298
2299 /*
2cfb7455
CL
2300 * was_frozen may have been set after we acquired the list_lock in
2301 * an earlier loop. So we need to check it here again.
81819f0f 2302 */
2cfb7455
CL
2303 if (was_frozen)
2304 stat(s, FREE_FROZEN);
2305 else {
2306 if (unlikely(!inuse && n->nr_partial > s->min_partial))
2307 goto slab_empty;
5cc6eee8 2308
2cfb7455
CL
2309 /*
2310 * Objects left in the slab. If it was not on the partial list before
2311 * then add it.
2312 */
2313 if (unlikely(!prior)) {
2314 remove_full(s, page);
2315 add_partial(n, page, 0);
2316 stat(s, FREE_ADD_PARTIAL);
2317 }
8ff12cfc 2318 }
80f08c19 2319 spin_unlock_irqrestore(&n->list_lock, flags);
81819f0f
CL
2320 return;
2321
2322slab_empty:
a973e9dd 2323 if (prior) {
81819f0f 2324 /*
672bba3a 2325 * Slab still on the partial list.
81819f0f 2326 */
5cc6eee8 2327 remove_partial(n, page);
84e554e6 2328 stat(s, FREE_REMOVE_PARTIAL);
8ff12cfc 2329 }
2cfb7455 2330
80f08c19 2331 spin_unlock_irqrestore(&n->list_lock, flags);
84e554e6 2332 stat(s, FREE_SLAB);
81819f0f 2333 discard_slab(s, page);
81819f0f
CL
2334}
2335
894b8788
CL
2336/*
2337 * Fastpath with forced inlining to produce a kfree and kmem_cache_free that
2338 * can perform fastpath freeing without additional function calls.
2339 *
2340 * The fastpath is only possible if we are freeing to the current cpu slab
2341 * of this processor. This typically the case if we have just allocated
2342 * the item before.
2343 *
2344 * If fastpath is not possible then fall back to __slab_free where we deal
2345 * with all sorts of special processing.
2346 */
06428780 2347static __always_inline void slab_free(struct kmem_cache *s,
ce71e27c 2348 struct page *page, void *x, unsigned long addr)
894b8788
CL
2349{
2350 void **object = (void *)x;
dfb4f096 2351 struct kmem_cache_cpu *c;
8a5ec0ba 2352 unsigned long tid;
1f84260c 2353
c016b0bd
CL
2354 slab_free_hook(s, x);
2355
8a5ec0ba 2356redo:
a24c5a0e 2357
8a5ec0ba
CL
2358 /*
2359 * Determine the currently cpus per cpu slab.
2360 * The cpu may change afterward. However that does not matter since
2361 * data is retrieved via this pointer. If we are on the same cpu
2362 * during the cmpxchg then the free will succedd.
2363 */
9dfc6e68 2364 c = __this_cpu_ptr(s->cpu_slab);
c016b0bd 2365
8a5ec0ba
CL
2366 tid = c->tid;
2367 barrier();
c016b0bd 2368
442b06bc 2369 if (likely(page == c->page)) {
ff12059e 2370 set_freepointer(s, object, c->freelist);
8a5ec0ba 2371
30106b8c 2372 if (unlikely(!irqsafe_cpu_cmpxchg_double(
8a5ec0ba
CL
2373 s->cpu_slab->freelist, s->cpu_slab->tid,
2374 c->freelist, tid,
2375 object, next_tid(tid)))) {
2376
2377 note_cmpxchg_failure("slab_free", s, tid);
2378 goto redo;
2379 }
84e554e6 2380 stat(s, FREE_FASTPATH);
894b8788 2381 } else
ff12059e 2382 __slab_free(s, page, x, addr);
894b8788 2383
894b8788
CL
2384}
2385
81819f0f
CL
2386void kmem_cache_free(struct kmem_cache *s, void *x)
2387{
77c5e2d0 2388 struct page *page;
81819f0f 2389
b49af68f 2390 page = virt_to_head_page(x);
81819f0f 2391
ce71e27c 2392 slab_free(s, page, x, _RET_IP_);
5b882be4 2393
ca2b84cb 2394 trace_kmem_cache_free(_RET_IP_, x);
81819f0f
CL
2395}
2396EXPORT_SYMBOL(kmem_cache_free);
2397
81819f0f 2398/*
672bba3a
CL
2399 * Object placement in a slab is made very easy because we always start at
2400 * offset 0. If we tune the size of the object to the alignment then we can
2401 * get the required alignment by putting one properly sized object after
2402 * another.
81819f0f
CL
2403 *
2404 * Notice that the allocation order determines the sizes of the per cpu
2405 * caches. Each processor has always one slab available for allocations.
2406 * Increasing the allocation order reduces the number of times that slabs
672bba3a 2407 * must be moved on and off the partial lists and is therefore a factor in
81819f0f 2408 * locking overhead.
81819f0f
CL
2409 */
2410
2411/*
2412 * Mininum / Maximum order of slab pages. This influences locking overhead
2413 * and slab fragmentation. A higher order reduces the number of partial slabs
2414 * and increases the number of allocations possible without having to
2415 * take the list_lock.
2416 */
2417static int slub_min_order;
114e9e89 2418static int slub_max_order = PAGE_ALLOC_COSTLY_ORDER;
9b2cd506 2419static int slub_min_objects;
81819f0f
CL
2420
2421/*
2422 * Merge control. If this is set then no merging of slab caches will occur.
672bba3a 2423 * (Could be removed. This was introduced to pacify the merge skeptics.)
81819f0f
CL
2424 */
2425static int slub_nomerge;
2426
81819f0f
CL
2427/*
2428 * Calculate the order of allocation given an slab object size.
2429 *
672bba3a
CL
2430 * The order of allocation has significant impact on performance and other
2431 * system components. Generally order 0 allocations should be preferred since
2432 * order 0 does not cause fragmentation in the page allocator. Larger objects
2433 * be problematic to put into order 0 slabs because there may be too much
c124f5b5 2434 * unused space left. We go to a higher order if more than 1/16th of the slab
672bba3a
CL
2435 * would be wasted.
2436 *
2437 * In order to reach satisfactory performance we must ensure that a minimum
2438 * number of objects is in one slab. Otherwise we may generate too much
2439 * activity on the partial lists which requires taking the list_lock. This is
2440 * less a concern for large slabs though which are rarely used.
81819f0f 2441 *
672bba3a
CL
2442 * slub_max_order specifies the order where we begin to stop considering the
2443 * number of objects in a slab as critical. If we reach slub_max_order then
2444 * we try to keep the page order as low as possible. So we accept more waste
2445 * of space in favor of a small page order.
81819f0f 2446 *
672bba3a
CL
2447 * Higher order allocations also allow the placement of more objects in a
2448 * slab and thereby reduce object handling overhead. If the user has
2449 * requested a higher mininum order then we start with that one instead of
2450 * the smallest order which will fit the object.
81819f0f 2451 */
5e6d444e 2452static inline int slab_order(int size, int min_objects,
ab9a0f19 2453 int max_order, int fract_leftover, int reserved)
81819f0f
CL
2454{
2455 int order;
2456 int rem;
6300ea75 2457 int min_order = slub_min_order;
81819f0f 2458
ab9a0f19 2459 if (order_objects(min_order, size, reserved) > MAX_OBJS_PER_PAGE)
210b5c06 2460 return get_order(size * MAX_OBJS_PER_PAGE) - 1;
39b26464 2461
6300ea75 2462 for (order = max(min_order,
5e6d444e
CL
2463 fls(min_objects * size - 1) - PAGE_SHIFT);
2464 order <= max_order; order++) {
81819f0f 2465
5e6d444e 2466 unsigned long slab_size = PAGE_SIZE << order;
81819f0f 2467
ab9a0f19 2468 if (slab_size < min_objects * size + reserved)
81819f0f
CL
2469 continue;
2470
ab9a0f19 2471 rem = (slab_size - reserved) % size;
81819f0f 2472
5e6d444e 2473 if (rem <= slab_size / fract_leftover)
81819f0f
CL
2474 break;
2475
2476 }
672bba3a 2477
81819f0f
CL
2478 return order;
2479}
2480
ab9a0f19 2481static inline int calculate_order(int size, int reserved)
5e6d444e
CL
2482{
2483 int order;
2484 int min_objects;
2485 int fraction;
e8120ff1 2486 int max_objects;
5e6d444e
CL
2487
2488 /*
2489 * Attempt to find best configuration for a slab. This
2490 * works by first attempting to generate a layout with
2491 * the best configuration and backing off gradually.
2492 *
2493 * First we reduce the acceptable waste in a slab. Then
2494 * we reduce the minimum objects required in a slab.
2495 */
2496 min_objects = slub_min_objects;
9b2cd506
CL
2497 if (!min_objects)
2498 min_objects = 4 * (fls(nr_cpu_ids) + 1);
ab9a0f19 2499 max_objects = order_objects(slub_max_order, size, reserved);
e8120ff1
ZY
2500 min_objects = min(min_objects, max_objects);
2501
5e6d444e 2502 while (min_objects > 1) {
c124f5b5 2503 fraction = 16;
5e6d444e
CL
2504 while (fraction >= 4) {
2505 order = slab_order(size, min_objects,
ab9a0f19 2506 slub_max_order, fraction, reserved);
5e6d444e
CL
2507 if (order <= slub_max_order)
2508 return order;
2509 fraction /= 2;
2510 }
5086c389 2511 min_objects--;
5e6d444e
CL
2512 }
2513
2514 /*
2515 * We were unable to place multiple objects in a slab. Now
2516 * lets see if we can place a single object there.
2517 */
ab9a0f19 2518 order = slab_order(size, 1, slub_max_order, 1, reserved);
5e6d444e
CL
2519 if (order <= slub_max_order)
2520 return order;
2521
2522 /*
2523 * Doh this slab cannot be placed using slub_max_order.
2524 */
ab9a0f19 2525 order = slab_order(size, 1, MAX_ORDER, 1, reserved);
818cf590 2526 if (order < MAX_ORDER)
5e6d444e
CL
2527 return order;
2528 return -ENOSYS;
2529}
2530
81819f0f 2531/*
672bba3a 2532 * Figure out what the alignment of the objects will be.
81819f0f
CL
2533 */
2534static unsigned long calculate_alignment(unsigned long flags,
2535 unsigned long align, unsigned long size)
2536{
2537 /*
6446faa2
CL
2538 * If the user wants hardware cache aligned objects then follow that
2539 * suggestion if the object is sufficiently large.
81819f0f 2540 *
6446faa2
CL
2541 * The hardware cache alignment cannot override the specified
2542 * alignment though. If that is greater then use it.
81819f0f 2543 */
b6210386
NP
2544 if (flags & SLAB_HWCACHE_ALIGN) {
2545 unsigned long ralign = cache_line_size();
2546 while (size <= ralign / 2)
2547 ralign /= 2;
2548 align = max(align, ralign);
2549 }
81819f0f
CL
2550
2551 if (align < ARCH_SLAB_MINALIGN)
b6210386 2552 align = ARCH_SLAB_MINALIGN;
81819f0f
CL
2553
2554 return ALIGN(align, sizeof(void *));
2555}
2556
5595cffc
PE
2557static void
2558init_kmem_cache_node(struct kmem_cache_node *n, struct kmem_cache *s)
81819f0f
CL
2559{
2560 n->nr_partial = 0;
81819f0f
CL
2561 spin_lock_init(&n->list_lock);
2562 INIT_LIST_HEAD(&n->partial);
8ab1372f 2563#ifdef CONFIG_SLUB_DEBUG
0f389ec6 2564 atomic_long_set(&n->nr_slabs, 0);
02b71b70 2565 atomic_long_set(&n->total_objects, 0);
643b1138 2566 INIT_LIST_HEAD(&n->full);
8ab1372f 2567#endif
81819f0f
CL
2568}
2569
55136592 2570static inline int alloc_kmem_cache_cpus(struct kmem_cache *s)
4c93c355 2571{
6c182dc0
CL
2572 BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE <
2573 SLUB_PAGE_SHIFT * sizeof(struct kmem_cache_cpu));
4c93c355 2574
8a5ec0ba 2575 /*
d4d84fef
CM
2576 * Must align to double word boundary for the double cmpxchg
2577 * instructions to work; see __pcpu_double_call_return_bool().
8a5ec0ba 2578 */
d4d84fef
CM
2579 s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu),
2580 2 * sizeof(void *));
8a5ec0ba
CL
2581
2582 if (!s->cpu_slab)
2583 return 0;
2584
2585 init_kmem_cache_cpus(s);
4c93c355 2586
8a5ec0ba 2587 return 1;
4c93c355 2588}
4c93c355 2589
51df1142
CL
2590static struct kmem_cache *kmem_cache_node;
2591
81819f0f
CL
2592/*
2593 * No kmalloc_node yet so do it by hand. We know that this is the first
2594 * slab on the node for this slabcache. There are no concurrent accesses
2595 * possible.
2596 *
2597 * Note that this function only works on the kmalloc_node_cache
4c93c355
CL
2598 * when allocating for the kmalloc_node_cache. This is used for bootstrapping
2599 * memory on a fresh node that has no slab structures yet.
81819f0f 2600 */
55136592 2601static void early_kmem_cache_node_alloc(int node)
81819f0f
CL
2602{
2603 struct page *page;
2604 struct kmem_cache_node *n;
2605
51df1142 2606 BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node));
81819f0f 2607
51df1142 2608 page = new_slab(kmem_cache_node, GFP_NOWAIT, node);
81819f0f
CL
2609
2610 BUG_ON(!page);
a2f92ee7
CL
2611 if (page_to_nid(page) != node) {
2612 printk(KERN_ERR "SLUB: Unable to allocate memory from "
2613 "node %d\n", node);
2614 printk(KERN_ERR "SLUB: Allocating a useless per node structure "
2615 "in order to be able to continue\n");
2616 }
2617
81819f0f
CL
2618 n = page->freelist;
2619 BUG_ON(!n);
51df1142 2620 page->freelist = get_freepointer(kmem_cache_node, n);
81819f0f 2621 page->inuse++;
8cb0a506 2622 page->frozen = 0;
51df1142 2623 kmem_cache_node->node[node] = n;
8ab1372f 2624#ifdef CONFIG_SLUB_DEBUG
f7cb1933 2625 init_object(kmem_cache_node, n, SLUB_RED_ACTIVE);
51df1142 2626 init_tracking(kmem_cache_node, n);
8ab1372f 2627#endif
51df1142
CL
2628 init_kmem_cache_node(n, kmem_cache_node);
2629 inc_slabs_node(kmem_cache_node, node, page->objects);
6446faa2 2630
7c2e132c 2631 add_partial(n, page, 0);
81819f0f
CL
2632}
2633
2634static void free_kmem_cache_nodes(struct kmem_cache *s)
2635{
2636 int node;
2637
f64dc58c 2638 for_each_node_state(node, N_NORMAL_MEMORY) {
81819f0f 2639 struct kmem_cache_node *n = s->node[node];
51df1142 2640
73367bd8 2641 if (n)
51df1142
CL
2642 kmem_cache_free(kmem_cache_node, n);
2643
81819f0f
CL
2644 s->node[node] = NULL;
2645 }
2646}
2647
55136592 2648static int init_kmem_cache_nodes(struct kmem_cache *s)
81819f0f
CL
2649{
2650 int node;
81819f0f 2651
f64dc58c 2652 for_each_node_state(node, N_NORMAL_MEMORY) {
81819f0f
CL
2653 struct kmem_cache_node *n;
2654
73367bd8 2655 if (slab_state == DOWN) {
55136592 2656 early_kmem_cache_node_alloc(node);
73367bd8
AD
2657 continue;
2658 }
51df1142 2659 n = kmem_cache_alloc_node(kmem_cache_node,
55136592 2660 GFP_KERNEL, node);
81819f0f 2661
73367bd8
AD
2662 if (!n) {
2663 free_kmem_cache_nodes(s);
2664 return 0;
81819f0f 2665 }
73367bd8 2666
81819f0f 2667 s->node[node] = n;
5595cffc 2668 init_kmem_cache_node(n, s);
81819f0f
CL
2669 }
2670 return 1;
2671}
81819f0f 2672
c0bdb232 2673static void set_min_partial(struct kmem_cache *s, unsigned long min)
3b89d7d8
DR
2674{
2675 if (min < MIN_PARTIAL)
2676 min = MIN_PARTIAL;
2677 else if (min > MAX_PARTIAL)
2678 min = MAX_PARTIAL;
2679 s->min_partial = min;
2680}
2681
81819f0f
CL
2682/*
2683 * calculate_sizes() determines the order and the distribution of data within
2684 * a slab object.
2685 */
06b285dc 2686static int calculate_sizes(struct kmem_cache *s, int forced_order)
81819f0f
CL
2687{
2688 unsigned long flags = s->flags;
2689 unsigned long size = s->objsize;
2690 unsigned long align = s->align;
834f3d11 2691 int order;
81819f0f 2692
d8b42bf5
CL
2693 /*
2694 * Round up object size to the next word boundary. We can only
2695 * place the free pointer at word boundaries and this determines
2696 * the possible location of the free pointer.
2697 */
2698 size = ALIGN(size, sizeof(void *));
2699
2700#ifdef CONFIG_SLUB_DEBUG
81819f0f
CL
2701 /*
2702 * Determine if we can poison the object itself. If the user of
2703 * the slab may touch the object after free or before allocation
2704 * then we should never poison the object itself.
2705 */
2706 if ((flags & SLAB_POISON) && !(flags & SLAB_DESTROY_BY_RCU) &&
c59def9f 2707 !s->ctor)
81819f0f
CL
2708 s->flags |= __OBJECT_POISON;
2709 else
2710 s->flags &= ~__OBJECT_POISON;
2711
81819f0f
CL
2712
2713 /*
672bba3a 2714 * If we are Redzoning then check if there is some space between the
81819f0f 2715 * end of the object and the free pointer. If not then add an
672bba3a 2716 * additional word to have some bytes to store Redzone information.
81819f0f
CL
2717 */
2718 if ((flags & SLAB_RED_ZONE) && size == s->objsize)
2719 size += sizeof(void *);
41ecc55b 2720#endif
81819f0f
CL
2721
2722 /*
672bba3a
CL
2723 * With that we have determined the number of bytes in actual use
2724 * by the object. This is the potential offset to the free pointer.
81819f0f
CL
2725 */
2726 s->inuse = size;
2727
2728 if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) ||
c59def9f 2729 s->ctor)) {
81819f0f
CL
2730 /*
2731 * Relocate free pointer after the object if it is not
2732 * permitted to overwrite the first word of the object on
2733 * kmem_cache_free.
2734 *
2735 * This is the case if we do RCU, have a constructor or
2736 * destructor or are poisoning the objects.
2737 */
2738 s->offset = size;
2739 size += sizeof(void *);
2740 }
2741
c12b3c62 2742#ifdef CONFIG_SLUB_DEBUG
81819f0f
CL
2743 if (flags & SLAB_STORE_USER)
2744 /*
2745 * Need to store information about allocs and frees after
2746 * the object.
2747 */
2748 size += 2 * sizeof(struct track);
2749
be7b3fbc 2750 if (flags & SLAB_RED_ZONE)
81819f0f
CL
2751 /*
2752 * Add some empty padding so that we can catch
2753 * overwrites from earlier objects rather than let
2754 * tracking information or the free pointer be
0211a9c8 2755 * corrupted if a user writes before the start
81819f0f
CL
2756 * of the object.
2757 */
2758 size += sizeof(void *);
41ecc55b 2759#endif
672bba3a 2760
81819f0f
CL
2761 /*
2762 * Determine the alignment based on various parameters that the
65c02d4c
CL
2763 * user specified and the dynamic determination of cache line size
2764 * on bootup.
81819f0f
CL
2765 */
2766 align = calculate_alignment(flags, align, s->objsize);
dcb0ce1b 2767 s->align = align;
81819f0f
CL
2768
2769 /*
2770 * SLUB stores one object immediately after another beginning from
2771 * offset 0. In order to align the objects we have to simply size
2772 * each object to conform to the alignment.
2773 */
2774 size = ALIGN(size, align);
2775 s->size = size;
06b285dc
CL
2776 if (forced_order >= 0)
2777 order = forced_order;
2778 else
ab9a0f19 2779 order = calculate_order(size, s->reserved);
81819f0f 2780
834f3d11 2781 if (order < 0)
81819f0f
CL
2782 return 0;
2783
b7a49f0d 2784 s->allocflags = 0;
834f3d11 2785 if (order)
b7a49f0d
CL
2786 s->allocflags |= __GFP_COMP;
2787
2788 if (s->flags & SLAB_CACHE_DMA)
2789 s->allocflags |= SLUB_DMA;
2790
2791 if (s->flags & SLAB_RECLAIM_ACCOUNT)
2792 s->allocflags |= __GFP_RECLAIMABLE;
2793
81819f0f
CL
2794 /*
2795 * Determine the number of objects per slab
2796 */
ab9a0f19
LJ
2797 s->oo = oo_make(order, size, s->reserved);
2798 s->min = oo_make(get_order(size), size, s->reserved);
205ab99d
CL
2799 if (oo_objects(s->oo) > oo_objects(s->max))
2800 s->max = s->oo;
81819f0f 2801
834f3d11 2802 return !!oo_objects(s->oo);
81819f0f
CL
2803
2804}
2805
55136592 2806static int kmem_cache_open(struct kmem_cache *s,
81819f0f
CL
2807 const char *name, size_t size,
2808 size_t align, unsigned long flags,
51cc5068 2809 void (*ctor)(void *))
81819f0f
CL
2810{
2811 memset(s, 0, kmem_size);
2812 s->name = name;
2813 s->ctor = ctor;
81819f0f 2814 s->objsize = size;
81819f0f 2815 s->align = align;
ba0268a8 2816 s->flags = kmem_cache_flags(size, flags, name, ctor);
ab9a0f19 2817 s->reserved = 0;
81819f0f 2818
da9a638c
LJ
2819 if (need_reserve_slab_rcu && (s->flags & SLAB_DESTROY_BY_RCU))
2820 s->reserved = sizeof(struct rcu_head);
81819f0f 2821
06b285dc 2822 if (!calculate_sizes(s, -1))
81819f0f 2823 goto error;
3de47213
DR
2824 if (disable_higher_order_debug) {
2825 /*
2826 * Disable debugging flags that store metadata if the min slab
2827 * order increased.
2828 */
2829 if (get_order(s->size) > get_order(s->objsize)) {
2830 s->flags &= ~DEBUG_METADATA_FLAGS;
2831 s->offset = 0;
2832 if (!calculate_sizes(s, -1))
2833 goto error;
2834 }
2835 }
81819f0f 2836
b789ef51
CL
2837#ifdef CONFIG_CMPXCHG_DOUBLE
2838 if (system_has_cmpxchg_double() && (s->flags & SLAB_DEBUG_FLAGS) == 0)
2839 /* Enable fast mode */
2840 s->flags |= __CMPXCHG_DOUBLE;
2841#endif
2842
3b89d7d8
DR
2843 /*
2844 * The larger the object size is, the more pages we want on the partial
2845 * list to avoid pounding the page allocator excessively.
2846 */
c0bdb232 2847 set_min_partial(s, ilog2(s->size));
81819f0f
CL
2848 s->refcount = 1;
2849#ifdef CONFIG_NUMA
e2cb96b7 2850 s->remote_node_defrag_ratio = 1000;
81819f0f 2851#endif
55136592 2852 if (!init_kmem_cache_nodes(s))
dfb4f096 2853 goto error;
81819f0f 2854
55136592 2855 if (alloc_kmem_cache_cpus(s))
81819f0f 2856 return 1;
ff12059e 2857
4c93c355 2858 free_kmem_cache_nodes(s);
81819f0f
CL
2859error:
2860 if (flags & SLAB_PANIC)
2861 panic("Cannot create slab %s size=%lu realsize=%u "
2862 "order=%u offset=%u flags=%lx\n",
834f3d11 2863 s->name, (unsigned long)size, s->size, oo_order(s->oo),
81819f0f
CL
2864 s->offset, flags);
2865 return 0;
2866}
81819f0f 2867
81819f0f
CL
2868/*
2869 * Determine the size of a slab object
2870 */
2871unsigned int kmem_cache_size(struct kmem_cache *s)
2872{
2873 return s->objsize;
2874}
2875EXPORT_SYMBOL(kmem_cache_size);
2876
33b12c38
CL
2877static void list_slab_objects(struct kmem_cache *s, struct page *page,
2878 const char *text)
2879{
2880#ifdef CONFIG_SLUB_DEBUG
2881 void *addr = page_address(page);
2882 void *p;
a5dd5c11
NK
2883 unsigned long *map = kzalloc(BITS_TO_LONGS(page->objects) *
2884 sizeof(long), GFP_ATOMIC);
bbd7d57b
ED
2885 if (!map)
2886 return;
33b12c38
CL
2887 slab_err(s, page, "%s", text);
2888 slab_lock(page);
33b12c38 2889
5f80b13a 2890 get_map(s, page, map);
33b12c38
CL
2891 for_each_object(p, s, addr, page->objects) {
2892
2893 if (!test_bit(slab_index(p, s, addr), map)) {
2894 printk(KERN_ERR "INFO: Object 0x%p @offset=%tu\n",
2895 p, p - addr);
2896 print_tracking(s, p);
2897 }
2898 }
2899 slab_unlock(page);
bbd7d57b 2900 kfree(map);
33b12c38
CL
2901#endif
2902}
2903
81819f0f 2904/*
599870b1 2905 * Attempt to free all partial slabs on a node.
81819f0f 2906 */
599870b1 2907static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
81819f0f 2908{
81819f0f
CL
2909 unsigned long flags;
2910 struct page *page, *h;
2911
2912 spin_lock_irqsave(&n->list_lock, flags);
33b12c38 2913 list_for_each_entry_safe(page, h, &n->partial, lru) {
81819f0f 2914 if (!page->inuse) {
5cc6eee8 2915 remove_partial(n, page);
81819f0f 2916 discard_slab(s, page);
33b12c38
CL
2917 } else {
2918 list_slab_objects(s, page,
2919 "Objects remaining on kmem_cache_close()");
599870b1 2920 }
33b12c38 2921 }
81819f0f 2922 spin_unlock_irqrestore(&n->list_lock, flags);
81819f0f
CL
2923}
2924
2925/*
672bba3a 2926 * Release all resources used by a slab cache.
81819f0f 2927 */
0c710013 2928static inline int kmem_cache_close(struct kmem_cache *s)
81819f0f
CL
2929{
2930 int node;
2931
2932 flush_all(s);
9dfc6e68 2933 free_percpu(s->cpu_slab);
81819f0f 2934 /* Attempt to free all objects */
f64dc58c 2935 for_each_node_state(node, N_NORMAL_MEMORY) {
81819f0f
CL
2936 struct kmem_cache_node *n = get_node(s, node);
2937
599870b1
CL
2938 free_partial(s, n);
2939 if (n->nr_partial || slabs_node(s, node))
81819f0f
CL
2940 return 1;
2941 }
2942 free_kmem_cache_nodes(s);
2943 return 0;
2944}
2945
2946/*
2947 * Close a cache and release the kmem_cache structure
2948 * (must be used for caches created using kmem_cache_create)
2949 */
2950void kmem_cache_destroy(struct kmem_cache *s)
2951{
2952 down_write(&slub_lock);
2953 s->refcount--;
2954 if (!s->refcount) {
2955 list_del(&s->list);
d629d819
PE
2956 if (kmem_cache_close(s)) {
2957 printk(KERN_ERR "SLUB %s: %s called for cache that "
2958 "still has objects.\n", s->name, __func__);
2959 dump_stack();
2960 }
d76b1590
ED
2961 if (s->flags & SLAB_DESTROY_BY_RCU)
2962 rcu_barrier();
81819f0f 2963 sysfs_slab_remove(s);
2bce6485
CL
2964 }
2965 up_write(&slub_lock);
81819f0f
CL
2966}
2967EXPORT_SYMBOL(kmem_cache_destroy);
2968
2969/********************************************************************
2970 * Kmalloc subsystem
2971 *******************************************************************/
2972
51df1142 2973struct kmem_cache *kmalloc_caches[SLUB_PAGE_SHIFT];
81819f0f
CL
2974EXPORT_SYMBOL(kmalloc_caches);
2975
51df1142
CL
2976static struct kmem_cache *kmem_cache;
2977
55136592 2978#ifdef CONFIG_ZONE_DMA
51df1142 2979static struct kmem_cache *kmalloc_dma_caches[SLUB_PAGE_SHIFT];
55136592
CL
2980#endif
2981
81819f0f
CL
2982static int __init setup_slub_min_order(char *str)
2983{
06428780 2984 get_option(&str, &slub_min_order);
81819f0f
CL
2985
2986 return 1;
2987}
2988
2989__setup("slub_min_order=", setup_slub_min_order);
2990
2991static int __init setup_slub_max_order(char *str)
2992{
06428780 2993 get_option(&str, &slub_max_order);
818cf590 2994 slub_max_order = min(slub_max_order, MAX_ORDER - 1);
81819f0f
CL
2995
2996 return 1;
2997}
2998
2999__setup("slub_max_order=", setup_slub_max_order);
3000
3001static int __init setup_slub_min_objects(char *str)
3002{
06428780 3003 get_option(&str, &slub_min_objects);
81819f0f
CL
3004
3005 return 1;
3006}
3007
3008__setup("slub_min_objects=", setup_slub_min_objects);
3009
3010static int __init setup_slub_nomerge(char *str)
3011{
3012 slub_nomerge = 1;
3013 return 1;
3014}
3015
3016__setup("slub_nomerge", setup_slub_nomerge);
3017
51df1142
CL
3018static struct kmem_cache *__init create_kmalloc_cache(const char *name,
3019 int size, unsigned int flags)
81819f0f 3020{
51df1142
CL
3021 struct kmem_cache *s;
3022
3023 s = kmem_cache_alloc(kmem_cache, GFP_NOWAIT);
3024
83b519e8
PE
3025 /*
3026 * This function is called with IRQs disabled during early-boot on
3027 * single CPU so there's no need to take slub_lock here.
3028 */
55136592 3029 if (!kmem_cache_open(s, name, size, ARCH_KMALLOC_MINALIGN,
319d1e24 3030 flags, NULL))
81819f0f
CL
3031 goto panic;
3032
3033 list_add(&s->list, &slab_caches);
51df1142 3034 return s;
81819f0f
CL
3035
3036panic:
3037 panic("Creation of kmalloc slab %s size=%d failed.\n", name, size);
51df1142 3038 return NULL;
81819f0f
CL
3039}
3040
f1b26339
CL
3041/*
3042 * Conversion table for small slabs sizes / 8 to the index in the
3043 * kmalloc array. This is necessary for slabs < 192 since we have non power
3044 * of two cache sizes there. The size of larger slabs can be determined using
3045 * fls.
3046 */
3047static s8 size_index[24] = {
3048 3, /* 8 */
3049 4, /* 16 */
3050 5, /* 24 */
3051 5, /* 32 */
3052 6, /* 40 */
3053 6, /* 48 */
3054 6, /* 56 */
3055 6, /* 64 */
3056 1, /* 72 */
3057 1, /* 80 */
3058 1, /* 88 */
3059 1, /* 96 */
3060 7, /* 104 */
3061 7, /* 112 */
3062 7, /* 120 */
3063 7, /* 128 */
3064 2, /* 136 */
3065 2, /* 144 */
3066 2, /* 152 */
3067 2, /* 160 */
3068 2, /* 168 */
3069 2, /* 176 */
3070 2, /* 184 */
3071 2 /* 192 */
3072};
3073
acdfcd04
AK
3074static inline int size_index_elem(size_t bytes)
3075{
3076 return (bytes - 1) / 8;
3077}
3078
81819f0f
CL
3079static struct kmem_cache *get_slab(size_t size, gfp_t flags)
3080{
f1b26339 3081 int index;
81819f0f 3082
f1b26339
CL
3083 if (size <= 192) {
3084 if (!size)
3085 return ZERO_SIZE_PTR;
81819f0f 3086
acdfcd04 3087 index = size_index[size_index_elem(size)];
aadb4bc4 3088 } else
f1b26339 3089 index = fls(size - 1);
81819f0f
CL
3090
3091#ifdef CONFIG_ZONE_DMA
f1b26339 3092 if (unlikely((flags & SLUB_DMA)))
51df1142 3093 return kmalloc_dma_caches[index];
f1b26339 3094
81819f0f 3095#endif
51df1142 3096 return kmalloc_caches[index];
81819f0f
CL
3097}
3098
3099void *__kmalloc(size_t size, gfp_t flags)
3100{
aadb4bc4 3101 struct kmem_cache *s;
5b882be4 3102 void *ret;
81819f0f 3103
ffadd4d0 3104 if (unlikely(size > SLUB_MAX_SIZE))
eada35ef 3105 return kmalloc_large(size, flags);
aadb4bc4
CL
3106
3107 s = get_slab(size, flags);
3108
3109 if (unlikely(ZERO_OR_NULL_PTR(s)))
6cb8f913
CL
3110 return s;
3111
2154a336 3112 ret = slab_alloc(s, flags, NUMA_NO_NODE, _RET_IP_);
5b882be4 3113
ca2b84cb 3114 trace_kmalloc(_RET_IP_, ret, size, s->size, flags);
5b882be4
EGM
3115
3116 return ret;
81819f0f
CL
3117}
3118EXPORT_SYMBOL(__kmalloc);
3119
5d1f57e4 3120#ifdef CONFIG_NUMA
f619cfe1
CL
3121static void *kmalloc_large_node(size_t size, gfp_t flags, int node)
3122{
b1eeab67 3123 struct page *page;
e4f7c0b4 3124 void *ptr = NULL;
f619cfe1 3125
b1eeab67
VN
3126 flags |= __GFP_COMP | __GFP_NOTRACK;
3127 page = alloc_pages_node(node, flags, get_order(size));
f619cfe1 3128 if (page)
e4f7c0b4
CM
3129 ptr = page_address(page);
3130
3131 kmemleak_alloc(ptr, size, 1, flags);
3132 return ptr;
f619cfe1
CL
3133}
3134
81819f0f
CL
3135void *__kmalloc_node(size_t size, gfp_t flags, int node)
3136{
aadb4bc4 3137 struct kmem_cache *s;
5b882be4 3138 void *ret;
81819f0f 3139
057685cf 3140 if (unlikely(size > SLUB_MAX_SIZE)) {
5b882be4
EGM
3141 ret = kmalloc_large_node(size, flags, node);
3142
ca2b84cb
EGM
3143 trace_kmalloc_node(_RET_IP_, ret,
3144 size, PAGE_SIZE << get_order(size),
3145 flags, node);
5b882be4
EGM
3146
3147 return ret;
3148 }
aadb4bc4
CL
3149
3150 s = get_slab(size, flags);
3151
3152 if (unlikely(ZERO_OR_NULL_PTR(s)))
6cb8f913
CL
3153 return s;
3154
5b882be4
EGM
3155 ret = slab_alloc(s, flags, node, _RET_IP_);
3156
ca2b84cb 3157 trace_kmalloc_node(_RET_IP_, ret, size, s->size, flags, node);
5b882be4
EGM
3158
3159 return ret;
81819f0f
CL
3160}
3161EXPORT_SYMBOL(__kmalloc_node);
3162#endif
3163
3164size_t ksize(const void *object)
3165{
272c1d21 3166 struct page *page;
81819f0f 3167
ef8b4520 3168 if (unlikely(object == ZERO_SIZE_PTR))
272c1d21
CL
3169 return 0;
3170
294a80a8 3171 page = virt_to_head_page(object);
294a80a8 3172
76994412
PE
3173 if (unlikely(!PageSlab(page))) {
3174 WARN_ON(!PageCompound(page));
294a80a8 3175 return PAGE_SIZE << compound_order(page);
76994412 3176 }
81819f0f 3177
b3d41885 3178 return slab_ksize(page->slab);
81819f0f 3179}
b1aabecd 3180EXPORT_SYMBOL(ksize);
81819f0f
CL
3181
3182void kfree(const void *x)
3183{
81819f0f 3184 struct page *page;
5bb983b0 3185 void *object = (void *)x;
81819f0f 3186
2121db74
PE
3187 trace_kfree(_RET_IP_, x);
3188
2408c550 3189 if (unlikely(ZERO_OR_NULL_PTR(x)))
81819f0f
CL
3190 return;
3191
b49af68f 3192 page = virt_to_head_page(x);
aadb4bc4 3193 if (unlikely(!PageSlab(page))) {
0937502a 3194 BUG_ON(!PageCompound(page));
e4f7c0b4 3195 kmemleak_free(x);
aadb4bc4
CL
3196 put_page(page);
3197 return;
3198 }
ce71e27c 3199 slab_free(page->slab, page, object, _RET_IP_);
81819f0f
CL
3200}
3201EXPORT_SYMBOL(kfree);
3202
2086d26a 3203/*
672bba3a
CL
3204 * kmem_cache_shrink removes empty slabs from the partial lists and sorts
3205 * the remaining slabs by the number of items in use. The slabs with the
3206 * most items in use come first. New allocations will then fill those up
3207 * and thus they can be removed from the partial lists.
3208 *
3209 * The slabs with the least items are placed last. This results in them
3210 * being allocated from last increasing the chance that the last objects
3211 * are freed in them.
2086d26a
CL
3212 */
3213int kmem_cache_shrink(struct kmem_cache *s)
3214{
3215 int node;
3216 int i;
3217 struct kmem_cache_node *n;
3218 struct page *page;
3219 struct page *t;
205ab99d 3220 int objects = oo_objects(s->max);
2086d26a 3221 struct list_head *slabs_by_inuse =
834f3d11 3222 kmalloc(sizeof(struct list_head) * objects, GFP_KERNEL);
2086d26a
CL
3223 unsigned long flags;
3224
3225 if (!slabs_by_inuse)
3226 return -ENOMEM;
3227
3228 flush_all(s);
f64dc58c 3229 for_each_node_state(node, N_NORMAL_MEMORY) {
2086d26a
CL
3230 n = get_node(s, node);
3231
3232 if (!n->nr_partial)
3233 continue;
3234
834f3d11 3235 for (i = 0; i < objects; i++)
2086d26a
CL
3236 INIT_LIST_HEAD(slabs_by_inuse + i);
3237
3238 spin_lock_irqsave(&n->list_lock, flags);
3239
3240 /*
672bba3a 3241 * Build lists indexed by the items in use in each slab.
2086d26a 3242 *
672bba3a
CL
3243 * Note that concurrent frees may occur while we hold the
3244 * list_lock. page->inuse here is the upper limit.
2086d26a
CL
3245 */
3246 list_for_each_entry_safe(page, t, &n->partial, lru) {
881db7fb 3247 if (!page->inuse) {
5cc6eee8 3248 remove_partial(n, page);
2086d26a
CL
3249 discard_slab(s, page);
3250 } else {
fcda3d89
CL
3251 list_move(&page->lru,
3252 slabs_by_inuse + page->inuse);
2086d26a
CL
3253 }
3254 }
3255
2086d26a 3256 /*
672bba3a
CL
3257 * Rebuild the partial list with the slabs filled up most
3258 * first and the least used slabs at the end.
2086d26a 3259 */
834f3d11 3260 for (i = objects - 1; i >= 0; i--)
2086d26a
CL
3261 list_splice(slabs_by_inuse + i, n->partial.prev);
3262
2086d26a
CL
3263 spin_unlock_irqrestore(&n->list_lock, flags);
3264 }
3265
3266 kfree(slabs_by_inuse);
3267 return 0;
3268}
3269EXPORT_SYMBOL(kmem_cache_shrink);
3270
92a5bbc1 3271#if defined(CONFIG_MEMORY_HOTPLUG)
b9049e23
YG
3272static int slab_mem_going_offline_callback(void *arg)
3273{
3274 struct kmem_cache *s;
3275
3276 down_read(&slub_lock);
3277 list_for_each_entry(s, &slab_caches, list)
3278 kmem_cache_shrink(s);
3279 up_read(&slub_lock);
3280
3281 return 0;
3282}
3283
3284static void slab_mem_offline_callback(void *arg)
3285{
3286 struct kmem_cache_node *n;
3287 struct kmem_cache *s;
3288 struct memory_notify *marg = arg;
3289 int offline_node;
3290
3291 offline_node = marg->status_change_nid;
3292
3293 /*
3294 * If the node still has available memory. we need kmem_cache_node
3295 * for it yet.
3296 */
3297 if (offline_node < 0)
3298 return;
3299
3300 down_read(&slub_lock);
3301 list_for_each_entry(s, &slab_caches, list) {
3302 n = get_node(s, offline_node);
3303 if (n) {
3304 /*
3305 * if n->nr_slabs > 0, slabs still exist on the node
3306 * that is going down. We were unable to free them,
c9404c9c 3307 * and offline_pages() function shouldn't call this
b9049e23
YG
3308 * callback. So, we must fail.
3309 */
0f389ec6 3310 BUG_ON(slabs_node(s, offline_node));
b9049e23
YG
3311
3312 s->node[offline_node] = NULL;
8de66a0c 3313 kmem_cache_free(kmem_cache_node, n);
b9049e23
YG
3314 }
3315 }
3316 up_read(&slub_lock);
3317}
3318
3319static int slab_mem_going_online_callback(void *arg)
3320{
3321 struct kmem_cache_node *n;
3322 struct kmem_cache *s;
3323 struct memory_notify *marg = arg;
3324 int nid = marg->status_change_nid;
3325 int ret = 0;
3326
3327 /*
3328 * If the node's memory is already available, then kmem_cache_node is
3329 * already created. Nothing to do.
3330 */
3331 if (nid < 0)
3332 return 0;
3333
3334 /*
0121c619 3335 * We are bringing a node online. No memory is available yet. We must
b9049e23
YG
3336 * allocate a kmem_cache_node structure in order to bring the node
3337 * online.
3338 */
3339 down_read(&slub_lock);
3340 list_for_each_entry(s, &slab_caches, list) {
3341 /*
3342 * XXX: kmem_cache_alloc_node will fallback to other nodes
3343 * since memory is not yet available from the node that
3344 * is brought up.
3345 */
8de66a0c 3346 n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL);
b9049e23
YG
3347 if (!n) {
3348 ret = -ENOMEM;
3349 goto out;
3350 }
5595cffc 3351 init_kmem_cache_node(n, s);
b9049e23
YG
3352 s->node[nid] = n;
3353 }
3354out:
3355 up_read(&slub_lock);
3356 return ret;
3357}
3358
3359static int slab_memory_callback(struct notifier_block *self,
3360 unsigned long action, void *arg)
3361{
3362 int ret = 0;
3363
3364 switch (action) {
3365 case MEM_GOING_ONLINE:
3366 ret = slab_mem_going_online_callback(arg);
3367 break;
3368 case MEM_GOING_OFFLINE:
3369 ret = slab_mem_going_offline_callback(arg);
3370 break;
3371 case MEM_OFFLINE:
3372 case MEM_CANCEL_ONLINE:
3373 slab_mem_offline_callback(arg);
3374 break;
3375 case MEM_ONLINE:
3376 case MEM_CANCEL_OFFLINE:
3377 break;
3378 }
dc19f9db
KH
3379 if (ret)
3380 ret = notifier_from_errno(ret);
3381 else
3382 ret = NOTIFY_OK;
b9049e23
YG
3383 return ret;
3384}
3385
3386#endif /* CONFIG_MEMORY_HOTPLUG */
3387
81819f0f
CL
3388/********************************************************************
3389 * Basic setup of slabs
3390 *******************************************************************/
3391
51df1142
CL
3392/*
3393 * Used for early kmem_cache structures that were allocated using
3394 * the page allocator
3395 */
3396
3397static void __init kmem_cache_bootstrap_fixup(struct kmem_cache *s)
3398{
3399 int node;
3400
3401 list_add(&s->list, &slab_caches);
3402 s->refcount = -1;
3403
3404 for_each_node_state(node, N_NORMAL_MEMORY) {
3405 struct kmem_cache_node *n = get_node(s, node);
3406 struct page *p;
3407
3408 if (n) {
3409 list_for_each_entry(p, &n->partial, lru)
3410 p->slab = s;
3411
607bf324 3412#ifdef CONFIG_SLUB_DEBUG
51df1142
CL
3413 list_for_each_entry(p, &n->full, lru)
3414 p->slab = s;
3415#endif
3416 }
3417 }
3418}
3419
81819f0f
CL
3420void __init kmem_cache_init(void)
3421{
3422 int i;
4b356be0 3423 int caches = 0;
51df1142
CL
3424 struct kmem_cache *temp_kmem_cache;
3425 int order;
51df1142
CL
3426 struct kmem_cache *temp_kmem_cache_node;
3427 unsigned long kmalloc_size;
3428
3429 kmem_size = offsetof(struct kmem_cache, node) +
3430 nr_node_ids * sizeof(struct kmem_cache_node *);
3431
3432 /* Allocate two kmem_caches from the page allocator */
3433 kmalloc_size = ALIGN(kmem_size, cache_line_size());
3434 order = get_order(2 * kmalloc_size);
3435 kmem_cache = (void *)__get_free_pages(GFP_NOWAIT, order);
3436
81819f0f
CL
3437 /*
3438 * Must first have the slab cache available for the allocations of the
672bba3a 3439 * struct kmem_cache_node's. There is special bootstrap code in
81819f0f
CL
3440 * kmem_cache_open for slab_state == DOWN.
3441 */
51df1142
CL
3442 kmem_cache_node = (void *)kmem_cache + kmalloc_size;
3443
3444 kmem_cache_open(kmem_cache_node, "kmem_cache_node",
3445 sizeof(struct kmem_cache_node),
3446 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
b9049e23 3447
0c40ba4f 3448 hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI);
81819f0f
CL
3449
3450 /* Able to allocate the per node structures */
3451 slab_state = PARTIAL;
3452
51df1142
CL
3453 temp_kmem_cache = kmem_cache;
3454 kmem_cache_open(kmem_cache, "kmem_cache", kmem_size,
3455 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
3456 kmem_cache = kmem_cache_alloc(kmem_cache, GFP_NOWAIT);
3457 memcpy(kmem_cache, temp_kmem_cache, kmem_size);
81819f0f 3458
51df1142
CL
3459 /*
3460 * Allocate kmem_cache_node properly from the kmem_cache slab.
3461 * kmem_cache_node is separately allocated so no need to
3462 * update any list pointers.
3463 */
3464 temp_kmem_cache_node = kmem_cache_node;
81819f0f 3465
51df1142
CL
3466 kmem_cache_node = kmem_cache_alloc(kmem_cache, GFP_NOWAIT);
3467 memcpy(kmem_cache_node, temp_kmem_cache_node, kmem_size);
3468
3469 kmem_cache_bootstrap_fixup(kmem_cache_node);
3470
3471 caches++;
51df1142
CL
3472 kmem_cache_bootstrap_fixup(kmem_cache);
3473 caches++;
3474 /* Free temporary boot structure */
3475 free_pages((unsigned long)temp_kmem_cache, order);
3476
3477 /* Now we can use the kmem_cache to allocate kmalloc slabs */
f1b26339
CL
3478
3479 /*
3480 * Patch up the size_index table if we have strange large alignment
3481 * requirements for the kmalloc array. This is only the case for
6446faa2 3482 * MIPS it seems. The standard arches will not generate any code here.
f1b26339
CL
3483 *
3484 * Largest permitted alignment is 256 bytes due to the way we
3485 * handle the index determination for the smaller caches.
3486 *
3487 * Make sure that nothing crazy happens if someone starts tinkering
3488 * around with ARCH_KMALLOC_MINALIGN
3489 */
3490 BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 ||
3491 (KMALLOC_MIN_SIZE & (KMALLOC_MIN_SIZE - 1)));
3492
acdfcd04
AK
3493 for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) {
3494 int elem = size_index_elem(i);
3495 if (elem >= ARRAY_SIZE(size_index))
3496 break;
3497 size_index[elem] = KMALLOC_SHIFT_LOW;
3498 }
f1b26339 3499
acdfcd04
AK
3500 if (KMALLOC_MIN_SIZE == 64) {
3501 /*
3502 * The 96 byte size cache is not used if the alignment
3503 * is 64 byte.
3504 */
3505 for (i = 64 + 8; i <= 96; i += 8)
3506 size_index[size_index_elem(i)] = 7;
3507 } else if (KMALLOC_MIN_SIZE == 128) {
41d54d3b
CL
3508 /*
3509 * The 192 byte sized cache is not used if the alignment
3510 * is 128 byte. Redirect kmalloc to use the 256 byte cache
3511 * instead.
3512 */
3513 for (i = 128 + 8; i <= 192; i += 8)
acdfcd04 3514 size_index[size_index_elem(i)] = 8;
41d54d3b
CL
3515 }
3516
51df1142
CL
3517 /* Caches that are not of the two-to-the-power-of size */
3518 if (KMALLOC_MIN_SIZE <= 32) {
3519 kmalloc_caches[1] = create_kmalloc_cache("kmalloc-96", 96, 0);
3520 caches++;
3521 }
3522
3523 if (KMALLOC_MIN_SIZE <= 64) {
3524 kmalloc_caches[2] = create_kmalloc_cache("kmalloc-192", 192, 0);
3525 caches++;
3526 }
3527
3528 for (i = KMALLOC_SHIFT_LOW; i < SLUB_PAGE_SHIFT; i++) {
3529 kmalloc_caches[i] = create_kmalloc_cache("kmalloc", 1 << i, 0);
3530 caches++;
3531 }
3532
81819f0f
CL
3533 slab_state = UP;
3534
3535 /* Provide the correct kmalloc names now that the caches are up */
84c1cf62
PE
3536 if (KMALLOC_MIN_SIZE <= 32) {
3537 kmalloc_caches[1]->name = kstrdup(kmalloc_caches[1]->name, GFP_NOWAIT);
3538 BUG_ON(!kmalloc_caches[1]->name);
3539 }
3540
3541 if (KMALLOC_MIN_SIZE <= 64) {
3542 kmalloc_caches[2]->name = kstrdup(kmalloc_caches[2]->name, GFP_NOWAIT);
3543 BUG_ON(!kmalloc_caches[2]->name);
3544 }
3545
d7278bd7
CL
3546 for (i = KMALLOC_SHIFT_LOW; i < SLUB_PAGE_SHIFT; i++) {
3547 char *s = kasprintf(GFP_NOWAIT, "kmalloc-%d", 1 << i);
3548
3549 BUG_ON(!s);
51df1142 3550 kmalloc_caches[i]->name = s;
d7278bd7 3551 }
81819f0f
CL
3552
3553#ifdef CONFIG_SMP
3554 register_cpu_notifier(&slab_notifier);
9dfc6e68 3555#endif
81819f0f 3556
55136592 3557#ifdef CONFIG_ZONE_DMA
51df1142
CL
3558 for (i = 0; i < SLUB_PAGE_SHIFT; i++) {
3559 struct kmem_cache *s = kmalloc_caches[i];
55136592 3560
51df1142 3561 if (s && s->size) {
55136592
CL
3562 char *name = kasprintf(GFP_NOWAIT,
3563 "dma-kmalloc-%d", s->objsize);
3564
3565 BUG_ON(!name);
51df1142
CL
3566 kmalloc_dma_caches[i] = create_kmalloc_cache(name,
3567 s->objsize, SLAB_CACHE_DMA);
55136592
CL
3568 }
3569 }
3570#endif
3adbefee
IM
3571 printk(KERN_INFO
3572 "SLUB: Genslabs=%d, HWalign=%d, Order=%d-%d, MinObjects=%d,"
4b356be0
CL
3573 " CPUs=%d, Nodes=%d\n",
3574 caches, cache_line_size(),
81819f0f
CL
3575 slub_min_order, slub_max_order, slub_min_objects,
3576 nr_cpu_ids, nr_node_ids);
3577}
3578
7e85ee0c
PE
3579void __init kmem_cache_init_late(void)
3580{
7e85ee0c
PE
3581}
3582
81819f0f
CL
3583/*
3584 * Find a mergeable slab cache
3585 */
3586static int slab_unmergeable(struct kmem_cache *s)
3587{
3588 if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE))
3589 return 1;
3590
c59def9f 3591 if (s->ctor)
81819f0f
CL
3592 return 1;
3593
8ffa6875
CL
3594 /*
3595 * We may have set a slab to be unmergeable during bootstrap.
3596 */
3597 if (s->refcount < 0)
3598 return 1;
3599
81819f0f
CL
3600 return 0;
3601}
3602
3603static struct kmem_cache *find_mergeable(size_t size,
ba0268a8 3604 size_t align, unsigned long flags, const char *name,
51cc5068 3605 void (*ctor)(void *))
81819f0f 3606{
5b95a4ac 3607 struct kmem_cache *s;
81819f0f
CL
3608
3609 if (slub_nomerge || (flags & SLUB_NEVER_MERGE))
3610 return NULL;
3611
c59def9f 3612 if (ctor)
81819f0f
CL
3613 return NULL;
3614
3615 size = ALIGN(size, sizeof(void *));
3616 align = calculate_alignment(flags, align, size);
3617 size = ALIGN(size, align);
ba0268a8 3618 flags = kmem_cache_flags(size, flags, name, NULL);
81819f0f 3619
5b95a4ac 3620 list_for_each_entry(s, &slab_caches, list) {
81819f0f
CL
3621 if (slab_unmergeable(s))
3622 continue;
3623
3624 if (size > s->size)
3625 continue;
3626
ba0268a8 3627 if ((flags & SLUB_MERGE_SAME) != (s->flags & SLUB_MERGE_SAME))
81819f0f
CL
3628 continue;
3629 /*
3630 * Check if alignment is compatible.
3631 * Courtesy of Adrian Drzewiecki
3632 */
06428780 3633 if ((s->size & ~(align - 1)) != s->size)
81819f0f
CL
3634 continue;
3635
3636 if (s->size - size >= sizeof(void *))
3637 continue;
3638
3639 return s;
3640 }
3641 return NULL;
3642}
3643
3644struct kmem_cache *kmem_cache_create(const char *name, size_t size,
51cc5068 3645 size_t align, unsigned long flags, void (*ctor)(void *))
81819f0f
CL
3646{
3647 struct kmem_cache *s;
84c1cf62 3648 char *n;
81819f0f 3649
fe1ff49d
BH
3650 if (WARN_ON(!name))
3651 return NULL;
3652
81819f0f 3653 down_write(&slub_lock);
ba0268a8 3654 s = find_mergeable(size, align, flags, name, ctor);
81819f0f
CL
3655 if (s) {
3656 s->refcount++;
3657 /*
3658 * Adjust the object sizes so that we clear
3659 * the complete object on kzalloc.
3660 */
3661 s->objsize = max(s->objsize, (int)size);
3662 s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *)));
6446faa2 3663
7b8f3b66 3664 if (sysfs_slab_alias(s, name)) {
7b8f3b66 3665 s->refcount--;
81819f0f 3666 goto err;
7b8f3b66 3667 }
2bce6485 3668 up_write(&slub_lock);
a0e1d1be
CL
3669 return s;
3670 }
6446faa2 3671
84c1cf62
PE
3672 n = kstrdup(name, GFP_KERNEL);
3673 if (!n)
3674 goto err;
3675
a0e1d1be
CL
3676 s = kmalloc(kmem_size, GFP_KERNEL);
3677 if (s) {
84c1cf62 3678 if (kmem_cache_open(s, n,
c59def9f 3679 size, align, flags, ctor)) {
81819f0f 3680 list_add(&s->list, &slab_caches);
7b8f3b66 3681 if (sysfs_slab_add(s)) {
7b8f3b66 3682 list_del(&s->list);
84c1cf62 3683 kfree(n);
7b8f3b66 3684 kfree(s);
a0e1d1be 3685 goto err;
7b8f3b66 3686 }
2bce6485 3687 up_write(&slub_lock);
a0e1d1be
CL
3688 return s;
3689 }
84c1cf62 3690 kfree(n);
a0e1d1be 3691 kfree(s);
81819f0f 3692 }
68cee4f1 3693err:
81819f0f 3694 up_write(&slub_lock);
81819f0f 3695
81819f0f
CL
3696 if (flags & SLAB_PANIC)
3697 panic("Cannot create slabcache %s\n", name);
3698 else
3699 s = NULL;
3700 return s;
3701}
3702EXPORT_SYMBOL(kmem_cache_create);
3703
81819f0f 3704#ifdef CONFIG_SMP
81819f0f 3705/*
672bba3a
CL
3706 * Use the cpu notifier to insure that the cpu slabs are flushed when
3707 * necessary.
81819f0f
CL
3708 */
3709static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
3710 unsigned long action, void *hcpu)
3711{
3712 long cpu = (long)hcpu;
5b95a4ac
CL
3713 struct kmem_cache *s;
3714 unsigned long flags;
81819f0f
CL
3715
3716 switch (action) {
3717 case CPU_UP_CANCELED:
8bb78442 3718 case CPU_UP_CANCELED_FROZEN:
81819f0f 3719 case CPU_DEAD:
8bb78442 3720 case CPU_DEAD_FROZEN:
5b95a4ac
CL
3721 down_read(&slub_lock);
3722 list_for_each_entry(s, &slab_caches, list) {
3723 local_irq_save(flags);
3724 __flush_cpu_slab(s, cpu);
3725 local_irq_restore(flags);
3726 }
3727 up_read(&slub_lock);
81819f0f
CL
3728 break;
3729 default:
3730 break;
3731 }
3732 return NOTIFY_OK;
3733}
3734
06428780 3735static struct notifier_block __cpuinitdata slab_notifier = {
3adbefee 3736 .notifier_call = slab_cpuup_callback
06428780 3737};
81819f0f
CL
3738
3739#endif
3740
ce71e27c 3741void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, unsigned long caller)
81819f0f 3742{
aadb4bc4 3743 struct kmem_cache *s;
94b528d0 3744 void *ret;
aadb4bc4 3745
ffadd4d0 3746 if (unlikely(size > SLUB_MAX_SIZE))
eada35ef
PE
3747 return kmalloc_large(size, gfpflags);
3748
aadb4bc4 3749 s = get_slab(size, gfpflags);
81819f0f 3750
2408c550 3751 if (unlikely(ZERO_OR_NULL_PTR(s)))
6cb8f913 3752 return s;
81819f0f 3753
2154a336 3754 ret = slab_alloc(s, gfpflags, NUMA_NO_NODE, caller);
94b528d0 3755
25985edc 3756 /* Honor the call site pointer we received. */
ca2b84cb 3757 trace_kmalloc(caller, ret, size, s->size, gfpflags);
94b528d0
EGM
3758
3759 return ret;
81819f0f
CL
3760}
3761
5d1f57e4 3762#ifdef CONFIG_NUMA
81819f0f 3763void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
ce71e27c 3764 int node, unsigned long caller)
81819f0f 3765{
aadb4bc4 3766 struct kmem_cache *s;
94b528d0 3767 void *ret;
aadb4bc4 3768
d3e14aa3
XF
3769 if (unlikely(size > SLUB_MAX_SIZE)) {
3770 ret = kmalloc_large_node(size, gfpflags, node);
3771
3772 trace_kmalloc_node(caller, ret,
3773 size, PAGE_SIZE << get_order(size),
3774 gfpflags, node);
3775
3776 return ret;
3777 }
eada35ef 3778
aadb4bc4 3779 s = get_slab(size, gfpflags);
81819f0f 3780
2408c550 3781 if (unlikely(ZERO_OR_NULL_PTR(s)))
6cb8f913 3782 return s;
81819f0f 3783
94b528d0
EGM
3784 ret = slab_alloc(s, gfpflags, node, caller);
3785
25985edc 3786 /* Honor the call site pointer we received. */
ca2b84cb 3787 trace_kmalloc_node(caller, ret, size, s->size, gfpflags, node);
94b528d0
EGM
3788
3789 return ret;
81819f0f 3790}
5d1f57e4 3791#endif
81819f0f 3792
ab4d5ed5 3793#ifdef CONFIG_SYSFS
205ab99d
CL
3794static int count_inuse(struct page *page)
3795{
3796 return page->inuse;
3797}
3798
3799static int count_total(struct page *page)
3800{
3801 return page->objects;
3802}
ab4d5ed5 3803#endif
205ab99d 3804
ab4d5ed5 3805#ifdef CONFIG_SLUB_DEBUG
434e245d
CL
3806static int validate_slab(struct kmem_cache *s, struct page *page,
3807 unsigned long *map)
53e15af0
CL
3808{
3809 void *p;
a973e9dd 3810 void *addr = page_address(page);
53e15af0
CL
3811
3812 if (!check_slab(s, page) ||
3813 !on_freelist(s, page, NULL))
3814 return 0;
3815
3816 /* Now we know that a valid freelist exists */
39b26464 3817 bitmap_zero(map, page->objects);
53e15af0 3818
5f80b13a
CL
3819 get_map(s, page, map);
3820 for_each_object(p, s, addr, page->objects) {
3821 if (test_bit(slab_index(p, s, addr), map))
3822 if (!check_object(s, page, p, SLUB_RED_INACTIVE))
3823 return 0;
53e15af0
CL
3824 }
3825
224a88be 3826 for_each_object(p, s, addr, page->objects)
7656c72b 3827 if (!test_bit(slab_index(p, s, addr), map))
37d57443 3828 if (!check_object(s, page, p, SLUB_RED_ACTIVE))
53e15af0
CL
3829 return 0;
3830 return 1;
3831}
3832
434e245d
CL
3833static void validate_slab_slab(struct kmem_cache *s, struct page *page,
3834 unsigned long *map)
53e15af0 3835{
881db7fb
CL
3836 slab_lock(page);
3837 validate_slab(s, page, map);
3838 slab_unlock(page);
53e15af0
CL
3839}
3840
434e245d
CL
3841static int validate_slab_node(struct kmem_cache *s,
3842 struct kmem_cache_node *n, unsigned long *map)
53e15af0
CL
3843{
3844 unsigned long count = 0;
3845 struct page *page;
3846 unsigned long flags;
3847
3848 spin_lock_irqsave(&n->list_lock, flags);
3849
3850 list_for_each_entry(page, &n->partial, lru) {
434e245d 3851 validate_slab_slab(s, page, map);
53e15af0
CL
3852 count++;
3853 }
3854 if (count != n->nr_partial)
3855 printk(KERN_ERR "SLUB %s: %ld partial slabs counted but "
3856 "counter=%ld\n", s->name, count, n->nr_partial);
3857
3858 if (!(s->flags & SLAB_STORE_USER))
3859 goto out;
3860
3861 list_for_each_entry(page, &n->full, lru) {
434e245d 3862 validate_slab_slab(s, page, map);
53e15af0
CL
3863 count++;
3864 }
3865 if (count != atomic_long_read(&n->nr_slabs))
3866 printk(KERN_ERR "SLUB: %s %ld slabs counted but "
3867 "counter=%ld\n", s->name, count,
3868 atomic_long_read(&n->nr_slabs));
3869
3870out:
3871 spin_unlock_irqrestore(&n->list_lock, flags);
3872 return count;
3873}
3874
434e245d 3875static long validate_slab_cache(struct kmem_cache *s)
53e15af0
CL
3876{
3877 int node;
3878 unsigned long count = 0;
205ab99d 3879 unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
434e245d
CL
3880 sizeof(unsigned long), GFP_KERNEL);
3881
3882 if (!map)
3883 return -ENOMEM;
53e15af0
CL
3884
3885 flush_all(s);
f64dc58c 3886 for_each_node_state(node, N_NORMAL_MEMORY) {
53e15af0
CL
3887 struct kmem_cache_node *n = get_node(s, node);
3888
434e245d 3889 count += validate_slab_node(s, n, map);
53e15af0 3890 }
434e245d 3891 kfree(map);
53e15af0
CL
3892 return count;
3893}
88a420e4 3894/*
672bba3a 3895 * Generate lists of code addresses where slabcache objects are allocated
88a420e4
CL
3896 * and freed.
3897 */
3898
3899struct location {
3900 unsigned long count;
ce71e27c 3901 unsigned long addr;
45edfa58
CL
3902 long long sum_time;
3903 long min_time;
3904 long max_time;
3905 long min_pid;
3906 long max_pid;
174596a0 3907 DECLARE_BITMAP(cpus, NR_CPUS);
45edfa58 3908 nodemask_t nodes;
88a420e4
CL
3909};
3910
3911struct loc_track {
3912 unsigned long max;
3913 unsigned long count;
3914 struct location *loc;
3915};
3916
3917static void free_loc_track(struct loc_track *t)
3918{
3919 if (t->max)
3920 free_pages((unsigned long)t->loc,
3921 get_order(sizeof(struct location) * t->max));
3922}
3923
68dff6a9 3924static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags)
88a420e4
CL
3925{
3926 struct location *l;
3927 int order;
3928
88a420e4
CL
3929 order = get_order(sizeof(struct location) * max);
3930
68dff6a9 3931 l = (void *)__get_free_pages(flags, order);
88a420e4
CL
3932 if (!l)
3933 return 0;
3934
3935 if (t->count) {
3936 memcpy(l, t->loc, sizeof(struct location) * t->count);
3937 free_loc_track(t);
3938 }
3939 t->max = max;
3940 t->loc = l;
3941 return 1;
3942}
3943
3944static int add_location(struct loc_track *t, struct kmem_cache *s,
45edfa58 3945 const struct track *track)
88a420e4
CL
3946{
3947 long start, end, pos;
3948 struct location *l;
ce71e27c 3949 unsigned long caddr;
45edfa58 3950 unsigned long age = jiffies - track->when;
88a420e4
CL
3951
3952 start = -1;
3953 end = t->count;
3954
3955 for ( ; ; ) {
3956 pos = start + (end - start + 1) / 2;
3957
3958 /*
3959 * There is nothing at "end". If we end up there
3960 * we need to add something to before end.
3961 */
3962 if (pos == end)
3963 break;
3964
3965 caddr = t->loc[pos].addr;
45edfa58
CL
3966 if (track->addr == caddr) {
3967
3968 l = &t->loc[pos];
3969 l->count++;
3970 if (track->when) {
3971 l->sum_time += age;
3972 if (age < l->min_time)
3973 l->min_time = age;
3974 if (age > l->max_time)
3975 l->max_time = age;
3976
3977 if (track->pid < l->min_pid)
3978 l->min_pid = track->pid;
3979 if (track->pid > l->max_pid)
3980 l->max_pid = track->pid;
3981
174596a0
RR
3982 cpumask_set_cpu(track->cpu,
3983 to_cpumask(l->cpus));
45edfa58
CL
3984 }
3985 node_set(page_to_nid(virt_to_page(track)), l->nodes);
88a420e4
CL
3986 return 1;
3987 }
3988
45edfa58 3989 if (track->addr < caddr)
88a420e4
CL
3990 end = pos;
3991 else
3992 start = pos;
3993 }
3994
3995 /*
672bba3a 3996 * Not found. Insert new tracking element.
88a420e4 3997 */
68dff6a9 3998 if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC))
88a420e4
CL
3999 return 0;
4000
4001 l = t->loc + pos;
4002 if (pos < t->count)
4003 memmove(l + 1, l,
4004 (t->count - pos) * sizeof(struct location));
4005 t->count++;
4006 l->count = 1;
45edfa58
CL
4007 l->addr = track->addr;
4008 l->sum_time = age;
4009 l->min_time = age;
4010 l->max_time = age;
4011 l->min_pid = track->pid;
4012 l->max_pid = track->pid;
174596a0
RR
4013 cpumask_clear(to_cpumask(l->cpus));
4014 cpumask_set_cpu(track->cpu, to_cpumask(l->cpus));
45edfa58
CL
4015 nodes_clear(l->nodes);
4016 node_set(page_to_nid(virt_to_page(track)), l->nodes);
88a420e4
CL
4017 return 1;
4018}
4019
4020static void process_slab(struct loc_track *t, struct kmem_cache *s,
bbd7d57b 4021 struct page *page, enum track_item alloc,
a5dd5c11 4022 unsigned long *map)
88a420e4 4023{
a973e9dd 4024 void *addr = page_address(page);
88a420e4
CL
4025 void *p;
4026
39b26464 4027 bitmap_zero(map, page->objects);
5f80b13a 4028 get_map(s, page, map);
88a420e4 4029
224a88be 4030 for_each_object(p, s, addr, page->objects)
45edfa58
CL
4031 if (!test_bit(slab_index(p, s, addr), map))
4032 add_location(t, s, get_track(s, p, alloc));
88a420e4
CL
4033}
4034
4035static int list_locations(struct kmem_cache *s, char *buf,
4036 enum track_item alloc)
4037{
e374d483 4038 int len = 0;
88a420e4 4039 unsigned long i;
68dff6a9 4040 struct loc_track t = { 0, 0, NULL };
88a420e4 4041 int node;
bbd7d57b
ED
4042 unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
4043 sizeof(unsigned long), GFP_KERNEL);
88a420e4 4044
bbd7d57b
ED
4045 if (!map || !alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location),
4046 GFP_TEMPORARY)) {
4047 kfree(map);
68dff6a9 4048 return sprintf(buf, "Out of memory\n");
bbd7d57b 4049 }
88a420e4
CL
4050 /* Push back cpu slabs */
4051 flush_all(s);
4052
f64dc58c 4053 for_each_node_state(node, N_NORMAL_MEMORY) {
88a420e4
CL
4054 struct kmem_cache_node *n = get_node(s, node);
4055 unsigned long flags;
4056 struct page *page;
4057
9e86943b 4058 if (!atomic_long_read(&n->nr_slabs))
88a420e4
CL
4059 continue;
4060
4061 spin_lock_irqsave(&n->list_lock, flags);
4062 list_for_each_entry(page, &n->partial, lru)
bbd7d57b 4063 process_slab(&t, s, page, alloc, map);
88a420e4 4064 list_for_each_entry(page, &n->full, lru)
bbd7d57b 4065 process_slab(&t, s, page, alloc, map);
88a420e4
CL
4066 spin_unlock_irqrestore(&n->list_lock, flags);
4067 }
4068
4069 for (i = 0; i < t.count; i++) {
45edfa58 4070 struct location *l = &t.loc[i];
88a420e4 4071
9c246247 4072 if (len > PAGE_SIZE - KSYM_SYMBOL_LEN - 100)
88a420e4 4073 break;
e374d483 4074 len += sprintf(buf + len, "%7ld ", l->count);
45edfa58
CL
4075
4076 if (l->addr)
62c70bce 4077 len += sprintf(buf + len, "%pS", (void *)l->addr);
88a420e4 4078 else
e374d483 4079 len += sprintf(buf + len, "<not-available>");
45edfa58
CL
4080
4081 if (l->sum_time != l->min_time) {
e374d483 4082 len += sprintf(buf + len, " age=%ld/%ld/%ld",
f8bd2258
RZ
4083 l->min_time,
4084 (long)div_u64(l->sum_time, l->count),
4085 l->max_time);
45edfa58 4086 } else
e374d483 4087 len += sprintf(buf + len, " age=%ld",
45edfa58
CL
4088 l->min_time);
4089
4090 if (l->min_pid != l->max_pid)
e374d483 4091 len += sprintf(buf + len, " pid=%ld-%ld",
45edfa58
CL
4092 l->min_pid, l->max_pid);
4093 else
e374d483 4094 len += sprintf(buf + len, " pid=%ld",
45edfa58
CL
4095 l->min_pid);
4096
174596a0
RR
4097 if (num_online_cpus() > 1 &&
4098 !cpumask_empty(to_cpumask(l->cpus)) &&
e374d483
HH
4099 len < PAGE_SIZE - 60) {
4100 len += sprintf(buf + len, " cpus=");
4101 len += cpulist_scnprintf(buf + len, PAGE_SIZE - len - 50,
174596a0 4102 to_cpumask(l->cpus));
45edfa58
CL
4103 }
4104
62bc62a8 4105 if (nr_online_nodes > 1 && !nodes_empty(l->nodes) &&
e374d483
HH
4106 len < PAGE_SIZE - 60) {
4107 len += sprintf(buf + len, " nodes=");
4108 len += nodelist_scnprintf(buf + len, PAGE_SIZE - len - 50,
45edfa58
CL
4109 l->nodes);
4110 }
4111
e374d483 4112 len += sprintf(buf + len, "\n");
88a420e4
CL
4113 }
4114
4115 free_loc_track(&t);
bbd7d57b 4116 kfree(map);
88a420e4 4117 if (!t.count)
e374d483
HH
4118 len += sprintf(buf, "No data\n");
4119 return len;
88a420e4 4120}
ab4d5ed5 4121#endif
88a420e4 4122
a5a84755
CL
4123#ifdef SLUB_RESILIENCY_TEST
4124static void resiliency_test(void)
4125{
4126 u8 *p;
4127
4128 BUILD_BUG_ON(KMALLOC_MIN_SIZE > 16 || SLUB_PAGE_SHIFT < 10);
4129
4130 printk(KERN_ERR "SLUB resiliency testing\n");
4131 printk(KERN_ERR "-----------------------\n");
4132 printk(KERN_ERR "A. Corruption after allocation\n");
4133
4134 p = kzalloc(16, GFP_KERNEL);
4135 p[16] = 0x12;
4136 printk(KERN_ERR "\n1. kmalloc-16: Clobber Redzone/next pointer"
4137 " 0x12->0x%p\n\n", p + 16);
4138
4139 validate_slab_cache(kmalloc_caches[4]);
4140
4141 /* Hmmm... The next two are dangerous */
4142 p = kzalloc(32, GFP_KERNEL);
4143 p[32 + sizeof(void *)] = 0x34;
4144 printk(KERN_ERR "\n2. kmalloc-32: Clobber next pointer/next slab"
4145 " 0x34 -> -0x%p\n", p);
4146 printk(KERN_ERR
4147 "If allocated object is overwritten then not detectable\n\n");
4148
4149 validate_slab_cache(kmalloc_caches[5]);
4150 p = kzalloc(64, GFP_KERNEL);
4151 p += 64 + (get_cycles() & 0xff) * sizeof(void *);
4152 *p = 0x56;
4153 printk(KERN_ERR "\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n",
4154 p);
4155 printk(KERN_ERR
4156 "If allocated object is overwritten then not detectable\n\n");
4157 validate_slab_cache(kmalloc_caches[6]);
4158
4159 printk(KERN_ERR "\nB. Corruption after free\n");
4160 p = kzalloc(128, GFP_KERNEL);
4161 kfree(p);
4162 *p = 0x78;
4163 printk(KERN_ERR "1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p);
4164 validate_slab_cache(kmalloc_caches[7]);
4165
4166 p = kzalloc(256, GFP_KERNEL);
4167 kfree(p);
4168 p[50] = 0x9a;
4169 printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n",
4170 p);
4171 validate_slab_cache(kmalloc_caches[8]);
4172
4173 p = kzalloc(512, GFP_KERNEL);
4174 kfree(p);
4175 p[512] = 0xab;
4176 printk(KERN_ERR "\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p);
4177 validate_slab_cache(kmalloc_caches[9]);
4178}
4179#else
4180#ifdef CONFIG_SYSFS
4181static void resiliency_test(void) {};
4182#endif
4183#endif
4184
ab4d5ed5 4185#ifdef CONFIG_SYSFS
81819f0f 4186enum slab_stat_type {
205ab99d
CL
4187 SL_ALL, /* All slabs */
4188 SL_PARTIAL, /* Only partially allocated slabs */
4189 SL_CPU, /* Only slabs used for cpu caches */
4190 SL_OBJECTS, /* Determine allocated objects not slabs */
4191 SL_TOTAL /* Determine object capacity not slabs */
81819f0f
CL
4192};
4193
205ab99d 4194#define SO_ALL (1 << SL_ALL)
81819f0f
CL
4195#define SO_PARTIAL (1 << SL_PARTIAL)
4196#define SO_CPU (1 << SL_CPU)
4197#define SO_OBJECTS (1 << SL_OBJECTS)
205ab99d 4198#define SO_TOTAL (1 << SL_TOTAL)
81819f0f 4199
62e5c4b4
CG
4200static ssize_t show_slab_objects(struct kmem_cache *s,
4201 char *buf, unsigned long flags)
81819f0f
CL
4202{
4203 unsigned long total = 0;
81819f0f
CL
4204 int node;
4205 int x;
4206 unsigned long *nodes;
4207 unsigned long *per_cpu;
4208
4209 nodes = kzalloc(2 * sizeof(unsigned long) * nr_node_ids, GFP_KERNEL);
62e5c4b4
CG
4210 if (!nodes)
4211 return -ENOMEM;
81819f0f
CL
4212 per_cpu = nodes + nr_node_ids;
4213
205ab99d
CL
4214 if (flags & SO_CPU) {
4215 int cpu;
81819f0f 4216
205ab99d 4217 for_each_possible_cpu(cpu) {
9dfc6e68 4218 struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
dfb4f096 4219
205ab99d
CL
4220 if (!c || c->node < 0)
4221 continue;
4222
4223 if (c->page) {
4224 if (flags & SO_TOTAL)
4225 x = c->page->objects;
4226 else if (flags & SO_OBJECTS)
4227 x = c->page->inuse;
81819f0f
CL
4228 else
4229 x = 1;
205ab99d 4230
81819f0f 4231 total += x;
205ab99d 4232 nodes[c->node] += x;
81819f0f 4233 }
205ab99d 4234 per_cpu[c->node]++;
81819f0f
CL
4235 }
4236 }
4237
04d94879 4238 lock_memory_hotplug();
ab4d5ed5 4239#ifdef CONFIG_SLUB_DEBUG
205ab99d
CL
4240 if (flags & SO_ALL) {
4241 for_each_node_state(node, N_NORMAL_MEMORY) {
4242 struct kmem_cache_node *n = get_node(s, node);
4243
4244 if (flags & SO_TOTAL)
4245 x = atomic_long_read(&n->total_objects);
4246 else if (flags & SO_OBJECTS)
4247 x = atomic_long_read(&n->total_objects) -
4248 count_partial(n, count_free);
81819f0f 4249
81819f0f 4250 else
205ab99d 4251 x = atomic_long_read(&n->nr_slabs);
81819f0f
CL
4252 total += x;
4253 nodes[node] += x;
4254 }
4255
ab4d5ed5
CL
4256 } else
4257#endif
4258 if (flags & SO_PARTIAL) {
205ab99d
CL
4259 for_each_node_state(node, N_NORMAL_MEMORY) {
4260 struct kmem_cache_node *n = get_node(s, node);
81819f0f 4261
205ab99d
CL
4262 if (flags & SO_TOTAL)
4263 x = count_partial(n, count_total);
4264 else if (flags & SO_OBJECTS)
4265 x = count_partial(n, count_inuse);
81819f0f 4266 else
205ab99d 4267 x = n->nr_partial;
81819f0f
CL
4268 total += x;
4269 nodes[node] += x;
4270 }
4271 }
81819f0f
CL
4272 x = sprintf(buf, "%lu", total);
4273#ifdef CONFIG_NUMA
f64dc58c 4274 for_each_node_state(node, N_NORMAL_MEMORY)
81819f0f
CL
4275 if (nodes[node])
4276 x += sprintf(buf + x, " N%d=%lu",
4277 node, nodes[node]);
4278#endif
04d94879 4279 unlock_memory_hotplug();
81819f0f
CL
4280 kfree(nodes);
4281 return x + sprintf(buf + x, "\n");
4282}
4283
ab4d5ed5 4284#ifdef CONFIG_SLUB_DEBUG
81819f0f
CL
4285static int any_slab_objects(struct kmem_cache *s)
4286{
4287 int node;
81819f0f 4288
dfb4f096 4289 for_each_online_node(node) {
81819f0f
CL
4290 struct kmem_cache_node *n = get_node(s, node);
4291
dfb4f096
CL
4292 if (!n)
4293 continue;
4294
4ea33e2d 4295 if (atomic_long_read(&n->total_objects))
81819f0f
CL
4296 return 1;
4297 }
4298 return 0;
4299}
ab4d5ed5 4300#endif
81819f0f
CL
4301
4302#define to_slab_attr(n) container_of(n, struct slab_attribute, attr)
4303#define to_slab(n) container_of(n, struct kmem_cache, kobj);
4304
4305struct slab_attribute {
4306 struct attribute attr;
4307 ssize_t (*show)(struct kmem_cache *s, char *buf);
4308 ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count);
4309};
4310
4311#define SLAB_ATTR_RO(_name) \
4312 static struct slab_attribute _name##_attr = __ATTR_RO(_name)
4313
4314#define SLAB_ATTR(_name) \
4315 static struct slab_attribute _name##_attr = \
4316 __ATTR(_name, 0644, _name##_show, _name##_store)
4317
81819f0f
CL
4318static ssize_t slab_size_show(struct kmem_cache *s, char *buf)
4319{
4320 return sprintf(buf, "%d\n", s->size);
4321}
4322SLAB_ATTR_RO(slab_size);
4323
4324static ssize_t align_show(struct kmem_cache *s, char *buf)
4325{
4326 return sprintf(buf, "%d\n", s->align);
4327}
4328SLAB_ATTR_RO(align);
4329
4330static ssize_t object_size_show(struct kmem_cache *s, char *buf)
4331{
4332 return sprintf(buf, "%d\n", s->objsize);
4333}
4334SLAB_ATTR_RO(object_size);
4335
4336static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf)
4337{
834f3d11 4338 return sprintf(buf, "%d\n", oo_objects(s->oo));
81819f0f
CL
4339}
4340SLAB_ATTR_RO(objs_per_slab);
4341
06b285dc
CL
4342static ssize_t order_store(struct kmem_cache *s,
4343 const char *buf, size_t length)
4344{
0121c619
CL
4345 unsigned long order;
4346 int err;
4347
4348 err = strict_strtoul(buf, 10, &order);
4349 if (err)
4350 return err;
06b285dc
CL
4351
4352 if (order > slub_max_order || order < slub_min_order)
4353 return -EINVAL;
4354
4355 calculate_sizes(s, order);
4356 return length;
4357}
4358
81819f0f
CL
4359static ssize_t order_show(struct kmem_cache *s, char *buf)
4360{
834f3d11 4361 return sprintf(buf, "%d\n", oo_order(s->oo));
81819f0f 4362}
06b285dc 4363SLAB_ATTR(order);
81819f0f 4364
73d342b1
DR
4365static ssize_t min_partial_show(struct kmem_cache *s, char *buf)
4366{
4367 return sprintf(buf, "%lu\n", s->min_partial);
4368}
4369
4370static ssize_t min_partial_store(struct kmem_cache *s, const char *buf,
4371 size_t length)
4372{
4373 unsigned long min;
4374 int err;
4375
4376 err = strict_strtoul(buf, 10, &min);
4377 if (err)
4378 return err;
4379
c0bdb232 4380 set_min_partial(s, min);
73d342b1
DR
4381 return length;
4382}
4383SLAB_ATTR(min_partial);
4384
81819f0f
CL
4385static ssize_t ctor_show(struct kmem_cache *s, char *buf)
4386{
62c70bce
JP
4387 if (!s->ctor)
4388 return 0;
4389 return sprintf(buf, "%pS\n", s->ctor);
81819f0f
CL
4390}
4391SLAB_ATTR_RO(ctor);
4392
81819f0f
CL
4393static ssize_t aliases_show(struct kmem_cache *s, char *buf)
4394{
4395 return sprintf(buf, "%d\n", s->refcount - 1);
4396}
4397SLAB_ATTR_RO(aliases);
4398
81819f0f
CL
4399static ssize_t partial_show(struct kmem_cache *s, char *buf)
4400{
d9acf4b7 4401 return show_slab_objects(s, buf, SO_PARTIAL);
81819f0f
CL
4402}
4403SLAB_ATTR_RO(partial);
4404
4405static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf)
4406{
d9acf4b7 4407 return show_slab_objects(s, buf, SO_CPU);
81819f0f
CL
4408}
4409SLAB_ATTR_RO(cpu_slabs);
4410
4411static ssize_t objects_show(struct kmem_cache *s, char *buf)
4412{
205ab99d 4413 return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS);
81819f0f
CL
4414}
4415SLAB_ATTR_RO(objects);
4416
205ab99d
CL
4417static ssize_t objects_partial_show(struct kmem_cache *s, char *buf)
4418{
4419 return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS);
4420}
4421SLAB_ATTR_RO(objects_partial);
4422
a5a84755
CL
4423static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf)
4424{
4425 return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT));
4426}
4427
4428static ssize_t reclaim_account_store(struct kmem_cache *s,
4429 const char *buf, size_t length)
4430{
4431 s->flags &= ~SLAB_RECLAIM_ACCOUNT;
4432 if (buf[0] == '1')
4433 s->flags |= SLAB_RECLAIM_ACCOUNT;
4434 return length;
4435}
4436SLAB_ATTR(reclaim_account);
4437
4438static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf)
4439{
4440 return sprintf(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN));
4441}
4442SLAB_ATTR_RO(hwcache_align);
4443
4444#ifdef CONFIG_ZONE_DMA
4445static ssize_t cache_dma_show(struct kmem_cache *s, char *buf)
4446{
4447 return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA));
4448}
4449SLAB_ATTR_RO(cache_dma);
4450#endif
4451
4452static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf)
4453{
4454 return sprintf(buf, "%d\n", !!(s->flags & SLAB_DESTROY_BY_RCU));
4455}
4456SLAB_ATTR_RO(destroy_by_rcu);
4457
ab9a0f19
LJ
4458static ssize_t reserved_show(struct kmem_cache *s, char *buf)
4459{
4460 return sprintf(buf, "%d\n", s->reserved);
4461}
4462SLAB_ATTR_RO(reserved);
4463
ab4d5ed5 4464#ifdef CONFIG_SLUB_DEBUG
a5a84755
CL
4465static ssize_t slabs_show(struct kmem_cache *s, char *buf)
4466{
4467 return show_slab_objects(s, buf, SO_ALL);
4468}
4469SLAB_ATTR_RO(slabs);
4470
205ab99d
CL
4471static ssize_t total_objects_show(struct kmem_cache *s, char *buf)
4472{
4473 return show_slab_objects(s, buf, SO_ALL|SO_TOTAL);
4474}
4475SLAB_ATTR_RO(total_objects);
4476
81819f0f
CL
4477static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf)
4478{
4479 return sprintf(buf, "%d\n", !!(s->flags & SLAB_DEBUG_FREE));
4480}
4481
4482static ssize_t sanity_checks_store(struct kmem_cache *s,
4483 const char *buf, size_t length)
4484{
4485 s->flags &= ~SLAB_DEBUG_FREE;
b789ef51
CL
4486 if (buf[0] == '1') {
4487 s->flags &= ~__CMPXCHG_DOUBLE;
81819f0f 4488 s->flags |= SLAB_DEBUG_FREE;
b789ef51 4489 }
81819f0f
CL
4490 return length;
4491}
4492SLAB_ATTR(sanity_checks);
4493
4494static ssize_t trace_show(struct kmem_cache *s, char *buf)
4495{
4496 return sprintf(buf, "%d\n", !!(s->flags & SLAB_TRACE));
4497}
4498
4499static ssize_t trace_store(struct kmem_cache *s, const char *buf,
4500 size_t length)
4501{
4502 s->flags &= ~SLAB_TRACE;
b789ef51
CL
4503 if (buf[0] == '1') {
4504 s->flags &= ~__CMPXCHG_DOUBLE;
81819f0f 4505 s->flags |= SLAB_TRACE;
b789ef51 4506 }
81819f0f
CL
4507 return length;
4508}
4509SLAB_ATTR(trace);
4510
81819f0f
CL
4511static ssize_t red_zone_show(struct kmem_cache *s, char *buf)
4512{
4513 return sprintf(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE));
4514}
4515
4516static ssize_t red_zone_store(struct kmem_cache *s,
4517 const char *buf, size_t length)
4518{
4519 if (any_slab_objects(s))
4520 return -EBUSY;
4521
4522 s->flags &= ~SLAB_RED_ZONE;
b789ef51
CL
4523 if (buf[0] == '1') {
4524 s->flags &= ~__CMPXCHG_DOUBLE;
81819f0f 4525 s->flags |= SLAB_RED_ZONE;
b789ef51 4526 }
06b285dc 4527 calculate_sizes(s, -1);
81819f0f
CL
4528 return length;
4529}
4530SLAB_ATTR(red_zone);
4531
4532static ssize_t poison_show(struct kmem_cache *s, char *buf)
4533{
4534 return sprintf(buf, "%d\n", !!(s->flags & SLAB_POISON));
4535}
4536
4537static ssize_t poison_store(struct kmem_cache *s,
4538 const char *buf, size_t length)
4539{
4540 if (any_slab_objects(s))
4541 return -EBUSY;
4542
4543 s->flags &= ~SLAB_POISON;
b789ef51
CL
4544 if (buf[0] == '1') {
4545 s->flags &= ~__CMPXCHG_DOUBLE;
81819f0f 4546 s->flags |= SLAB_POISON;
b789ef51 4547 }
06b285dc 4548 calculate_sizes(s, -1);
81819f0f
CL
4549 return length;
4550}
4551SLAB_ATTR(poison);
4552
4553static ssize_t store_user_show(struct kmem_cache *s, char *buf)
4554{
4555 return sprintf(buf, "%d\n", !!(s->flags & SLAB_STORE_USER));
4556}
4557
4558static ssize_t store_user_store(struct kmem_cache *s,
4559 const char *buf, size_t length)
4560{
4561 if (any_slab_objects(s))
4562 return -EBUSY;
4563
4564 s->flags &= ~SLAB_STORE_USER;
b789ef51
CL
4565 if (buf[0] == '1') {
4566 s->flags &= ~__CMPXCHG_DOUBLE;
81819f0f 4567 s->flags |= SLAB_STORE_USER;
b789ef51 4568 }
06b285dc 4569 calculate_sizes(s, -1);
81819f0f
CL
4570 return length;
4571}
4572SLAB_ATTR(store_user);
4573
53e15af0
CL
4574static ssize_t validate_show(struct kmem_cache *s, char *buf)
4575{
4576 return 0;
4577}
4578
4579static ssize_t validate_store(struct kmem_cache *s,
4580 const char *buf, size_t length)
4581{
434e245d
CL
4582 int ret = -EINVAL;
4583
4584 if (buf[0] == '1') {
4585 ret = validate_slab_cache(s);
4586 if (ret >= 0)
4587 ret = length;
4588 }
4589 return ret;
53e15af0
CL
4590}
4591SLAB_ATTR(validate);
a5a84755
CL
4592
4593static ssize_t alloc_calls_show(struct kmem_cache *s, char *buf)
4594{
4595 if (!(s->flags & SLAB_STORE_USER))
4596 return -ENOSYS;
4597 return list_locations(s, buf, TRACK_ALLOC);
4598}
4599SLAB_ATTR_RO(alloc_calls);
4600
4601static ssize_t free_calls_show(struct kmem_cache *s, char *buf)
4602{
4603 if (!(s->flags & SLAB_STORE_USER))
4604 return -ENOSYS;
4605 return list_locations(s, buf, TRACK_FREE);
4606}
4607SLAB_ATTR_RO(free_calls);
4608#endif /* CONFIG_SLUB_DEBUG */
4609
4610#ifdef CONFIG_FAILSLAB
4611static ssize_t failslab_show(struct kmem_cache *s, char *buf)
4612{
4613 return sprintf(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB));
4614}
4615
4616static ssize_t failslab_store(struct kmem_cache *s, const char *buf,
4617 size_t length)
4618{
4619 s->flags &= ~SLAB_FAILSLAB;
4620 if (buf[0] == '1')
4621 s->flags |= SLAB_FAILSLAB;
4622 return length;
4623}
4624SLAB_ATTR(failslab);
ab4d5ed5 4625#endif
53e15af0 4626
2086d26a
CL
4627static ssize_t shrink_show(struct kmem_cache *s, char *buf)
4628{
4629 return 0;
4630}
4631
4632static ssize_t shrink_store(struct kmem_cache *s,
4633 const char *buf, size_t length)
4634{
4635 if (buf[0] == '1') {
4636 int rc = kmem_cache_shrink(s);
4637
4638 if (rc)
4639 return rc;
4640 } else
4641 return -EINVAL;
4642 return length;
4643}
4644SLAB_ATTR(shrink);
4645
81819f0f 4646#ifdef CONFIG_NUMA
9824601e 4647static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf)
81819f0f 4648{
9824601e 4649 return sprintf(buf, "%d\n", s->remote_node_defrag_ratio / 10);
81819f0f
CL
4650}
4651
9824601e 4652static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s,
81819f0f
CL
4653 const char *buf, size_t length)
4654{
0121c619
CL
4655 unsigned long ratio;
4656 int err;
4657
4658 err = strict_strtoul(buf, 10, &ratio);
4659 if (err)
4660 return err;
4661
e2cb96b7 4662 if (ratio <= 100)
0121c619 4663 s->remote_node_defrag_ratio = ratio * 10;
81819f0f 4664
81819f0f
CL
4665 return length;
4666}
9824601e 4667SLAB_ATTR(remote_node_defrag_ratio);
81819f0f
CL
4668#endif
4669
8ff12cfc 4670#ifdef CONFIG_SLUB_STATS
8ff12cfc
CL
4671static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si)
4672{
4673 unsigned long sum = 0;
4674 int cpu;
4675 int len;
4676 int *data = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL);
4677
4678 if (!data)
4679 return -ENOMEM;
4680
4681 for_each_online_cpu(cpu) {
9dfc6e68 4682 unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si];
8ff12cfc
CL
4683
4684 data[cpu] = x;
4685 sum += x;
4686 }
4687
4688 len = sprintf(buf, "%lu", sum);
4689
50ef37b9 4690#ifdef CONFIG_SMP
8ff12cfc
CL
4691 for_each_online_cpu(cpu) {
4692 if (data[cpu] && len < PAGE_SIZE - 20)
50ef37b9 4693 len += sprintf(buf + len, " C%d=%u", cpu, data[cpu]);
8ff12cfc 4694 }
50ef37b9 4695#endif
8ff12cfc
CL
4696 kfree(data);
4697 return len + sprintf(buf + len, "\n");
4698}
4699
78eb00cc
DR
4700static void clear_stat(struct kmem_cache *s, enum stat_item si)
4701{
4702 int cpu;
4703
4704 for_each_online_cpu(cpu)
9dfc6e68 4705 per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0;
78eb00cc
DR
4706}
4707
8ff12cfc
CL
4708#define STAT_ATTR(si, text) \
4709static ssize_t text##_show(struct kmem_cache *s, char *buf) \
4710{ \
4711 return show_stat(s, buf, si); \
4712} \
78eb00cc
DR
4713static ssize_t text##_store(struct kmem_cache *s, \
4714 const char *buf, size_t length) \
4715{ \
4716 if (buf[0] != '0') \
4717 return -EINVAL; \
4718 clear_stat(s, si); \
4719 return length; \
4720} \
4721SLAB_ATTR(text); \
8ff12cfc
CL
4722
4723STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath);
4724STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath);
4725STAT_ATTR(FREE_FASTPATH, free_fastpath);
4726STAT_ATTR(FREE_SLOWPATH, free_slowpath);
4727STAT_ATTR(FREE_FROZEN, free_frozen);
4728STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial);
4729STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial);
4730STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial);
4731STAT_ATTR(ALLOC_SLAB, alloc_slab);
4732STAT_ATTR(ALLOC_REFILL, alloc_refill);
e36a2652 4733STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch);
8ff12cfc
CL
4734STAT_ATTR(FREE_SLAB, free_slab);
4735STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush);
4736STAT_ATTR(DEACTIVATE_FULL, deactivate_full);
4737STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty);
4738STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head);
4739STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail);
4740STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees);
03e404af 4741STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass);
65c3376a 4742STAT_ATTR(ORDER_FALLBACK, order_fallback);
b789ef51
CL
4743STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail);
4744STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail);
8ff12cfc
CL
4745#endif
4746
06428780 4747static struct attribute *slab_attrs[] = {
81819f0f
CL
4748 &slab_size_attr.attr,
4749 &object_size_attr.attr,
4750 &objs_per_slab_attr.attr,
4751 &order_attr.attr,
73d342b1 4752 &min_partial_attr.attr,
81819f0f 4753 &objects_attr.attr,
205ab99d 4754 &objects_partial_attr.attr,
81819f0f
CL
4755 &partial_attr.attr,
4756 &cpu_slabs_attr.attr,
4757 &ctor_attr.attr,
81819f0f
CL
4758 &aliases_attr.attr,
4759 &align_attr.attr,
81819f0f
CL
4760 &hwcache_align_attr.attr,
4761 &reclaim_account_attr.attr,
4762 &destroy_by_rcu_attr.attr,
a5a84755 4763 &shrink_attr.attr,
ab9a0f19 4764 &reserved_attr.attr,
ab4d5ed5 4765#ifdef CONFIG_SLUB_DEBUG
a5a84755
CL
4766 &total_objects_attr.attr,
4767 &slabs_attr.attr,
4768 &sanity_checks_attr.attr,
4769 &trace_attr.attr,
81819f0f
CL
4770 &red_zone_attr.attr,
4771 &poison_attr.attr,
4772 &store_user_attr.attr,
53e15af0 4773 &validate_attr.attr,
88a420e4
CL
4774 &alloc_calls_attr.attr,
4775 &free_calls_attr.attr,
ab4d5ed5 4776#endif
81819f0f
CL
4777#ifdef CONFIG_ZONE_DMA
4778 &cache_dma_attr.attr,
4779#endif
4780#ifdef CONFIG_NUMA
9824601e 4781 &remote_node_defrag_ratio_attr.attr,
8ff12cfc
CL
4782#endif
4783#ifdef CONFIG_SLUB_STATS
4784 &alloc_fastpath_attr.attr,
4785 &alloc_slowpath_attr.attr,
4786 &free_fastpath_attr.attr,
4787 &free_slowpath_attr.attr,
4788 &free_frozen_attr.attr,
4789 &free_add_partial_attr.attr,
4790 &free_remove_partial_attr.attr,
4791 &alloc_from_partial_attr.attr,
4792 &alloc_slab_attr.attr,
4793 &alloc_refill_attr.attr,
e36a2652 4794 &alloc_node_mismatch_attr.attr,
8ff12cfc
CL
4795 &free_slab_attr.attr,
4796 &cpuslab_flush_attr.attr,
4797 &deactivate_full_attr.attr,
4798 &deactivate_empty_attr.attr,
4799 &deactivate_to_head_attr.attr,
4800 &deactivate_to_tail_attr.attr,
4801 &deactivate_remote_frees_attr.attr,
03e404af 4802 &deactivate_bypass_attr.attr,
65c3376a 4803 &order_fallback_attr.attr,
b789ef51
CL
4804 &cmpxchg_double_fail_attr.attr,
4805 &cmpxchg_double_cpu_fail_attr.attr,
81819f0f 4806#endif
4c13dd3b
DM
4807#ifdef CONFIG_FAILSLAB
4808 &failslab_attr.attr,
4809#endif
4810
81819f0f
CL
4811 NULL
4812};
4813
4814static struct attribute_group slab_attr_group = {
4815 .attrs = slab_attrs,
4816};
4817
4818static ssize_t slab_attr_show(struct kobject *kobj,
4819 struct attribute *attr,
4820 char *buf)
4821{
4822 struct slab_attribute *attribute;
4823 struct kmem_cache *s;
4824 int err;
4825
4826 attribute = to_slab_attr(attr);
4827 s = to_slab(kobj);
4828
4829 if (!attribute->show)
4830 return -EIO;
4831
4832 err = attribute->show(s, buf);
4833
4834 return err;
4835}
4836
4837static ssize_t slab_attr_store(struct kobject *kobj,
4838 struct attribute *attr,
4839 const char *buf, size_t len)
4840{
4841 struct slab_attribute *attribute;
4842 struct kmem_cache *s;
4843 int err;
4844
4845 attribute = to_slab_attr(attr);
4846 s = to_slab(kobj);
4847
4848 if (!attribute->store)
4849 return -EIO;
4850
4851 err = attribute->store(s, buf, len);
4852
4853 return err;
4854}
4855
151c602f
CL
4856static void kmem_cache_release(struct kobject *kobj)
4857{
4858 struct kmem_cache *s = to_slab(kobj);
4859
84c1cf62 4860 kfree(s->name);
151c602f
CL
4861 kfree(s);
4862}
4863
52cf25d0 4864static const struct sysfs_ops slab_sysfs_ops = {
81819f0f
CL
4865 .show = slab_attr_show,
4866 .store = slab_attr_store,
4867};
4868
4869static struct kobj_type slab_ktype = {
4870 .sysfs_ops = &slab_sysfs_ops,
151c602f 4871 .release = kmem_cache_release
81819f0f
CL
4872};
4873
4874static int uevent_filter(struct kset *kset, struct kobject *kobj)
4875{
4876 struct kobj_type *ktype = get_ktype(kobj);
4877
4878 if (ktype == &slab_ktype)
4879 return 1;
4880 return 0;
4881}
4882
9cd43611 4883static const struct kset_uevent_ops slab_uevent_ops = {
81819f0f
CL
4884 .filter = uevent_filter,
4885};
4886
27c3a314 4887static struct kset *slab_kset;
81819f0f
CL
4888
4889#define ID_STR_LENGTH 64
4890
4891/* Create a unique string id for a slab cache:
6446faa2
CL
4892 *
4893 * Format :[flags-]size
81819f0f
CL
4894 */
4895static char *create_unique_id(struct kmem_cache *s)
4896{
4897 char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL);
4898 char *p = name;
4899
4900 BUG_ON(!name);
4901
4902 *p++ = ':';
4903 /*
4904 * First flags affecting slabcache operations. We will only
4905 * get here for aliasable slabs so we do not need to support
4906 * too many flags. The flags here must cover all flags that
4907 * are matched during merging to guarantee that the id is
4908 * unique.
4909 */
4910 if (s->flags & SLAB_CACHE_DMA)
4911 *p++ = 'd';
4912 if (s->flags & SLAB_RECLAIM_ACCOUNT)
4913 *p++ = 'a';
4914 if (s->flags & SLAB_DEBUG_FREE)
4915 *p++ = 'F';
5a896d9e
VN
4916 if (!(s->flags & SLAB_NOTRACK))
4917 *p++ = 't';
81819f0f
CL
4918 if (p != name + 1)
4919 *p++ = '-';
4920 p += sprintf(p, "%07d", s->size);
4921 BUG_ON(p > name + ID_STR_LENGTH - 1);
4922 return name;
4923}
4924
4925static int sysfs_slab_add(struct kmem_cache *s)
4926{
4927 int err;
4928 const char *name;
4929 int unmergeable;
4930
4931 if (slab_state < SYSFS)
4932 /* Defer until later */
4933 return 0;
4934
4935 unmergeable = slab_unmergeable(s);
4936 if (unmergeable) {
4937 /*
4938 * Slabcache can never be merged so we can use the name proper.
4939 * This is typically the case for debug situations. In that
4940 * case we can catch duplicate names easily.
4941 */
27c3a314 4942 sysfs_remove_link(&slab_kset->kobj, s->name);
81819f0f
CL
4943 name = s->name;
4944 } else {
4945 /*
4946 * Create a unique name for the slab as a target
4947 * for the symlinks.
4948 */
4949 name = create_unique_id(s);
4950 }
4951
27c3a314 4952 s->kobj.kset = slab_kset;
1eada11c
GKH
4953 err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, name);
4954 if (err) {
4955 kobject_put(&s->kobj);
81819f0f 4956 return err;
1eada11c 4957 }
81819f0f
CL
4958
4959 err = sysfs_create_group(&s->kobj, &slab_attr_group);
5788d8ad
XF
4960 if (err) {
4961 kobject_del(&s->kobj);
4962 kobject_put(&s->kobj);
81819f0f 4963 return err;
5788d8ad 4964 }
81819f0f
CL
4965 kobject_uevent(&s->kobj, KOBJ_ADD);
4966 if (!unmergeable) {
4967 /* Setup first alias */
4968 sysfs_slab_alias(s, s->name);
4969 kfree(name);
4970 }
4971 return 0;
4972}
4973
4974static void sysfs_slab_remove(struct kmem_cache *s)
4975{
2bce6485
CL
4976 if (slab_state < SYSFS)
4977 /*
4978 * Sysfs has not been setup yet so no need to remove the
4979 * cache from sysfs.
4980 */
4981 return;
4982
81819f0f
CL
4983 kobject_uevent(&s->kobj, KOBJ_REMOVE);
4984 kobject_del(&s->kobj);
151c602f 4985 kobject_put(&s->kobj);
81819f0f
CL
4986}
4987
4988/*
4989 * Need to buffer aliases during bootup until sysfs becomes
9f6c708e 4990 * available lest we lose that information.
81819f0f
CL
4991 */
4992struct saved_alias {
4993 struct kmem_cache *s;
4994 const char *name;
4995 struct saved_alias *next;
4996};
4997
5af328a5 4998static struct saved_alias *alias_list;
81819f0f
CL
4999
5000static int sysfs_slab_alias(struct kmem_cache *s, const char *name)
5001{
5002 struct saved_alias *al;
5003
5004 if (slab_state == SYSFS) {
5005 /*
5006 * If we have a leftover link then remove it.
5007 */
27c3a314
GKH
5008 sysfs_remove_link(&slab_kset->kobj, name);
5009 return sysfs_create_link(&slab_kset->kobj, &s->kobj, name);
81819f0f
CL
5010 }
5011
5012 al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL);
5013 if (!al)
5014 return -ENOMEM;
5015
5016 al->s = s;
5017 al->name = name;
5018 al->next = alias_list;
5019 alias_list = al;
5020 return 0;
5021}
5022
5023static int __init slab_sysfs_init(void)
5024{
5b95a4ac 5025 struct kmem_cache *s;
81819f0f
CL
5026 int err;
5027
2bce6485
CL
5028 down_write(&slub_lock);
5029
0ff21e46 5030 slab_kset = kset_create_and_add("slab", &slab_uevent_ops, kernel_kobj);
27c3a314 5031 if (!slab_kset) {
2bce6485 5032 up_write(&slub_lock);
81819f0f
CL
5033 printk(KERN_ERR "Cannot register slab subsystem.\n");
5034 return -ENOSYS;
5035 }
5036
26a7bd03
CL
5037 slab_state = SYSFS;
5038
5b95a4ac 5039 list_for_each_entry(s, &slab_caches, list) {
26a7bd03 5040 err = sysfs_slab_add(s);
5d540fb7
CL
5041 if (err)
5042 printk(KERN_ERR "SLUB: Unable to add boot slab %s"
5043 " to sysfs\n", s->name);
26a7bd03 5044 }
81819f0f
CL
5045
5046 while (alias_list) {
5047 struct saved_alias *al = alias_list;
5048
5049 alias_list = alias_list->next;
5050 err = sysfs_slab_alias(al->s, al->name);
5d540fb7
CL
5051 if (err)
5052 printk(KERN_ERR "SLUB: Unable to add boot slab alias"
5053 " %s to sysfs\n", s->name);
81819f0f
CL
5054 kfree(al);
5055 }
5056
2bce6485 5057 up_write(&slub_lock);
81819f0f
CL
5058 resiliency_test();
5059 return 0;
5060}
5061
5062__initcall(slab_sysfs_init);
ab4d5ed5 5063#endif /* CONFIG_SYSFS */
57ed3eda
PE
5064
5065/*
5066 * The /proc/slabinfo ABI
5067 */
158a9624 5068#ifdef CONFIG_SLABINFO
57ed3eda
PE
5069static void print_slabinfo_header(struct seq_file *m)
5070{
5071 seq_puts(m, "slabinfo - version: 2.1\n");
5072 seq_puts(m, "# name <active_objs> <num_objs> <objsize> "
5073 "<objperslab> <pagesperslab>");
5074 seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
5075 seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
5076 seq_putc(m, '\n');
5077}
5078
5079static void *s_start(struct seq_file *m, loff_t *pos)
5080{
5081 loff_t n = *pos;
5082
5083 down_read(&slub_lock);
5084 if (!n)
5085 print_slabinfo_header(m);
5086
5087 return seq_list_start(&slab_caches, *pos);
5088}
5089
5090static void *s_next(struct seq_file *m, void *p, loff_t *pos)
5091{
5092 return seq_list_next(p, &slab_caches, pos);
5093}
5094
5095static void s_stop(struct seq_file *m, void *p)
5096{
5097 up_read(&slub_lock);
5098}
5099
5100static int s_show(struct seq_file *m, void *p)
5101{
5102 unsigned long nr_partials = 0;
5103 unsigned long nr_slabs = 0;
5104 unsigned long nr_inuse = 0;
205ab99d
CL
5105 unsigned long nr_objs = 0;
5106 unsigned long nr_free = 0;
57ed3eda
PE
5107 struct kmem_cache *s;
5108 int node;
5109
5110 s = list_entry(p, struct kmem_cache, list);
5111
5112 for_each_online_node(node) {
5113 struct kmem_cache_node *n = get_node(s, node);
5114
5115 if (!n)
5116 continue;
5117
5118 nr_partials += n->nr_partial;
5119 nr_slabs += atomic_long_read(&n->nr_slabs);
205ab99d
CL
5120 nr_objs += atomic_long_read(&n->total_objects);
5121 nr_free += count_partial(n, count_free);
57ed3eda
PE
5122 }
5123
205ab99d 5124 nr_inuse = nr_objs - nr_free;
57ed3eda
PE
5125
5126 seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", s->name, nr_inuse,
834f3d11
CL
5127 nr_objs, s->size, oo_objects(s->oo),
5128 (1 << oo_order(s->oo)));
57ed3eda
PE
5129 seq_printf(m, " : tunables %4u %4u %4u", 0, 0, 0);
5130 seq_printf(m, " : slabdata %6lu %6lu %6lu", nr_slabs, nr_slabs,
5131 0UL);
5132 seq_putc(m, '\n');
5133 return 0;
5134}
5135
7b3c3a50 5136static const struct seq_operations slabinfo_op = {
57ed3eda
PE
5137 .start = s_start,
5138 .next = s_next,
5139 .stop = s_stop,
5140 .show = s_show,
5141};
5142
7b3c3a50
AD
5143static int slabinfo_open(struct inode *inode, struct file *file)
5144{
5145 return seq_open(file, &slabinfo_op);
5146}
5147
5148static const struct file_operations proc_slabinfo_operations = {
5149 .open = slabinfo_open,
5150 .read = seq_read,
5151 .llseek = seq_lseek,
5152 .release = seq_release,
5153};
5154
5155static int __init slab_proc_init(void)
5156{
cf5d1131 5157 proc_create("slabinfo", S_IRUGO, NULL, &proc_slabinfo_operations);
7b3c3a50
AD
5158 return 0;
5159}
5160module_init(slab_proc_init);
158a9624 5161#endif /* CONFIG_SLABINFO */
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