blob: 35f351f26193a47145cd8bcb7f55ae091331ca97 [file] [log] [blame]
Christoph Lameter81819f02007-05-06 14:49:36 -07001/*
2 * SLUB: A slab allocator that limits cache line use instead of queuing
3 * objects in per cpu and per node lists.
4 *
5 * The allocator synchronizes using per slab locks and only
6 * uses a centralized lock to manage a pool of partial slabs.
7 *
Christoph Lametercde53532008-07-04 09:59:22 -07008 * (C) 2007 SGI, Christoph Lameter
Christoph Lameter81819f02007-05-06 14:49:36 -07009 */
10
11#include <linux/mm.h>
Nick Piggin1eb5ac62009-05-05 19:13:44 +100012#include <linux/swap.h> /* struct reclaim_state */
Christoph Lameter81819f02007-05-06 14:49:36 -070013#include <linux/module.h>
14#include <linux/bit_spinlock.h>
15#include <linux/interrupt.h>
16#include <linux/bitops.h>
17#include <linux/slab.h>
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +040018#include <linux/proc_fs.h>
Christoph Lameter81819f02007-05-06 14:49:36 -070019#include <linux/seq_file.h>
Vegard Nossum5a896d92008-04-04 00:54:48 +020020#include <linux/kmemcheck.h>
Christoph Lameter81819f02007-05-06 14:49:36 -070021#include <linux/cpu.h>
22#include <linux/cpuset.h>
23#include <linux/mempolicy.h>
24#include <linux/ctype.h>
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -070025#include <linux/debugobjects.h>
Christoph Lameter81819f02007-05-06 14:49:36 -070026#include <linux/kallsyms.h>
Yasunori Gotob9049e22007-10-21 16:41:37 -070027#include <linux/memory.h>
Roman Zippelf8bd2252008-05-01 04:34:31 -070028#include <linux/math64.h>
Akinobu Mita773ff602008-12-23 19:37:01 +090029#include <linux/fault-inject.h>
Christoph Lameter81819f02007-05-06 14:49:36 -070030
Richard Kennedy4a923792010-10-21 10:29:19 +010031#include <trace/events/kmem.h>
32
Christoph Lameter81819f02007-05-06 14:49:36 -070033/*
34 * Lock order:
35 * 1. slab_lock(page)
36 * 2. slab->list_lock
37 *
38 * The slab_lock protects operations on the object of a particular
39 * slab and its metadata in the page struct. If the slab lock
40 * has been taken then no allocations nor frees can be performed
41 * on the objects in the slab nor can the slab be added or removed
42 * from the partial or full lists since this would mean modifying
43 * the page_struct of the slab.
44 *
45 * The list_lock protects the partial and full list on each node and
46 * the partial slab counter. If taken then no new slabs may be added or
47 * removed from the lists nor make the number of partial slabs be modified.
48 * (Note that the total number of slabs is an atomic value that may be
49 * modified without taking the list lock).
50 *
51 * The list_lock is a centralized lock and thus we avoid taking it as
52 * much as possible. As long as SLUB does not have to handle partial
53 * slabs, operations can continue without any centralized lock. F.e.
54 * allocating a long series of objects that fill up slabs does not require
55 * the list lock.
56 *
57 * The lock order is sometimes inverted when we are trying to get a slab
58 * off a list. We take the list_lock and then look for a page on the list
59 * to use. While we do that objects in the slabs may be freed. We can
60 * only operate on the slab if we have also taken the slab_lock. So we use
61 * a slab_trylock() on the slab. If trylock was successful then no frees
62 * can occur anymore and we can use the slab for allocations etc. If the
63 * slab_trylock() does not succeed then frees are in progress in the slab and
64 * we must stay away from it for a while since we may cause a bouncing
65 * cacheline if we try to acquire the lock. So go onto the next slab.
66 * If all pages are busy then we may allocate a new slab instead of reusing
Lucas De Marchi25985ed2011-03-30 22:57:33 -030067 * a partial slab. A new slab has no one operating on it and thus there is
Christoph Lameter81819f02007-05-06 14:49:36 -070068 * no danger of cacheline contention.
69 *
70 * Interrupts are disabled during allocation and deallocation in order to
71 * make the slab allocator safe to use in the context of an irq. In addition
72 * interrupts are disabled to ensure that the processor does not change
73 * while handling per_cpu slabs, due to kernel preemption.
74 *
75 * SLUB assigns one slab for allocation to each processor.
76 * Allocations only occur from these slabs called cpu slabs.
77 *
Christoph Lameter672bba32007-05-09 02:32:39 -070078 * Slabs with free elements are kept on a partial list and during regular
79 * operations no list for full slabs is used. If an object in a full slab is
Christoph Lameter81819f02007-05-06 14:49:36 -070080 * freed then the slab will show up again on the partial lists.
Christoph Lameter672bba32007-05-09 02:32:39 -070081 * We track full slabs for debugging purposes though because otherwise we
82 * cannot scan all objects.
Christoph Lameter81819f02007-05-06 14:49:36 -070083 *
84 * Slabs are freed when they become empty. Teardown and setup is
85 * minimal so we rely on the page allocators per cpu caches for
86 * fast frees and allocs.
87 *
88 * Overloading of page flags that are otherwise used for LRU management.
89 *
Christoph Lameter4b6f0752007-05-16 22:10:53 -070090 * PageActive The slab is frozen and exempt from list processing.
91 * This means that the slab is dedicated to a purpose
92 * such as satisfying allocations for a specific
93 * processor. Objects may be freed in the slab while
94 * it is frozen but slab_free will then skip the usual
95 * list operations. It is up to the processor holding
96 * the slab to integrate the slab into the slab lists
97 * when the slab is no longer needed.
98 *
99 * One use of this flag is to mark slabs that are
100 * used for allocations. Then such a slab becomes a cpu
101 * slab. The cpu slab may be equipped with an additional
Christoph Lameterdfb4f092007-10-16 01:26:05 -0700102 * freelist that allows lockless access to
Christoph Lameter894b8782007-05-10 03:15:16 -0700103 * free objects in addition to the regular freelist
104 * that requires the slab lock.
Christoph Lameter81819f02007-05-06 14:49:36 -0700105 *
106 * PageError Slab requires special handling due to debug
107 * options set. This moves slab handling out of
Christoph Lameter894b8782007-05-10 03:15:16 -0700108 * the fast path and disables lockless freelists.
Christoph Lameter81819f02007-05-06 14:49:36 -0700109 */
110
Christoph Lameteraf537b02010-07-09 14:07:14 -0500111#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
112 SLAB_TRACE | SLAB_DEBUG_FREE)
113
114static inline int kmem_cache_debug(struct kmem_cache *s)
115{
Christoph Lameter5577bd82007-05-16 22:10:56 -0700116#ifdef CONFIG_SLUB_DEBUG
Christoph Lameteraf537b02010-07-09 14:07:14 -0500117 return unlikely(s->flags & SLAB_DEBUG_FLAGS);
Christoph Lameter5577bd82007-05-16 22:10:56 -0700118#else
Christoph Lameteraf537b02010-07-09 14:07:14 -0500119 return 0;
Christoph Lameter5577bd82007-05-16 22:10:56 -0700120#endif
Christoph Lameteraf537b02010-07-09 14:07:14 -0500121}
Christoph Lameter5577bd82007-05-16 22:10:56 -0700122
Christoph Lameter81819f02007-05-06 14:49:36 -0700123/*
124 * Issues still to be resolved:
125 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700126 * - Support PAGE_ALLOC_DEBUG. Should be easy to do.
127 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700128 * - Variable sizing of the per node arrays
129 */
130
131/* Enable to test recovery from slab corruption on boot */
132#undef SLUB_RESILIENCY_TEST
133
Christoph Lameter81819f02007-05-06 14:49:36 -0700134/*
Christoph Lameter2086d262007-05-06 14:49:46 -0700135 * Mininum number of partial slabs. These will be left on the partial
136 * lists even if they are empty. kmem_cache_shrink may reclaim them.
137 */
Christoph Lameter76be8952007-12-21 14:37:37 -0800138#define MIN_PARTIAL 5
Christoph Lametere95eed52007-05-06 14:49:44 -0700139
Christoph Lameter2086d262007-05-06 14:49:46 -0700140/*
141 * Maximum number of desirable partial slabs.
142 * The existence of more partial slabs makes kmem_cache_shrink
143 * sort the partial list by the number of objects in the.
144 */
145#define MAX_PARTIAL 10
146
Christoph Lameter81819f02007-05-06 14:49:36 -0700147#define DEBUG_DEFAULT_FLAGS (SLAB_DEBUG_FREE | SLAB_RED_ZONE | \
148 SLAB_POISON | SLAB_STORE_USER)
Christoph Lameter672bba32007-05-09 02:32:39 -0700149
Christoph Lameter81819f02007-05-06 14:49:36 -0700150/*
David Rientjes3de47212009-07-27 18:30:35 -0700151 * Debugging flags that require metadata to be stored in the slab. These get
152 * disabled when slub_debug=O is used and a cache's min order increases with
153 * metadata.
David Rientjesfa5ec8a2009-07-07 00:14:14 -0700154 */
David Rientjes3de47212009-07-27 18:30:35 -0700155#define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
David Rientjesfa5ec8a2009-07-07 00:14:14 -0700156
157/*
Christoph Lameter81819f02007-05-06 14:49:36 -0700158 * Set of flags that will prevent slab merging
159 */
160#define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +0300161 SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \
162 SLAB_FAILSLAB)
Christoph Lameter81819f02007-05-06 14:49:36 -0700163
164#define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \
Vegard Nossum5a896d92008-04-04 00:54:48 +0200165 SLAB_CACHE_DMA | SLAB_NOTRACK)
Christoph Lameter81819f02007-05-06 14:49:36 -0700166
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400167#define OO_SHIFT 16
168#define OO_MASK ((1 << OO_SHIFT) - 1)
169#define MAX_OBJS_PER_PAGE 65535 /* since page.objects is u16 */
170
Christoph Lameter81819f02007-05-06 14:49:36 -0700171/* Internal SLUB flags */
Christoph Lameterf90ec392010-07-09 14:07:11 -0500172#define __OBJECT_POISON 0x80000000UL /* Poison object */
Christoph Lameter81819f02007-05-06 14:49:36 -0700173
174static int kmem_size = sizeof(struct kmem_cache);
175
176#ifdef CONFIG_SMP
177static struct notifier_block slab_notifier;
178#endif
179
180static enum {
181 DOWN, /* No slab functionality available */
Christoph Lameter51df1142010-08-20 12:37:15 -0500182 PARTIAL, /* Kmem_cache_node works */
Christoph Lameter672bba32007-05-09 02:32:39 -0700183 UP, /* Everything works but does not show up in sysfs */
Christoph Lameter81819f02007-05-06 14:49:36 -0700184 SYSFS /* Sysfs up */
185} slab_state = DOWN;
186
187/* A list of all slab caches on the system */
188static DECLARE_RWSEM(slub_lock);
Adrian Bunk5af328a2007-07-17 04:03:27 -0700189static LIST_HEAD(slab_caches);
Christoph Lameter81819f02007-05-06 14:49:36 -0700190
Christoph Lameter02cbc872007-05-09 02:32:43 -0700191/*
192 * Tracking user of a slab.
193 */
194struct track {
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300195 unsigned long addr; /* Called from address */
Christoph Lameter02cbc872007-05-09 02:32:43 -0700196 int cpu; /* Was running on cpu */
197 int pid; /* Pid context */
198 unsigned long when; /* When did the operation occur */
199};
200
201enum track_item { TRACK_ALLOC, TRACK_FREE };
202
Christoph Lameterab4d5ed2010-10-05 13:57:26 -0500203#ifdef CONFIG_SYSFS
Christoph Lameter81819f02007-05-06 14:49:36 -0700204static int sysfs_slab_add(struct kmem_cache *);
205static int sysfs_slab_alias(struct kmem_cache *, const char *);
206static void sysfs_slab_remove(struct kmem_cache *);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800207
Christoph Lameter81819f02007-05-06 14:49:36 -0700208#else
Christoph Lameter0c710012007-07-17 04:03:24 -0700209static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; }
210static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p)
211 { return 0; }
Christoph Lameter151c6022008-01-07 22:29:05 -0800212static inline void sysfs_slab_remove(struct kmem_cache *s)
213{
Pekka Enberg84c1cf62010-09-14 23:21:12 +0300214 kfree(s->name);
Christoph Lameter151c6022008-01-07 22:29:05 -0800215 kfree(s);
216}
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800217
Christoph Lameter81819f02007-05-06 14:49:36 -0700218#endif
219
Christoph Lameter4fdccdf2011-03-22 13:35:00 -0500220static inline void stat(const struct kmem_cache *s, enum stat_item si)
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800221{
222#ifdef CONFIG_SLUB_STATS
Christoph Lameter84e554e62009-12-18 16:26:23 -0600223 __this_cpu_inc(s->cpu_slab->stat[si]);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800224#endif
225}
226
Christoph Lameter81819f02007-05-06 14:49:36 -0700227/********************************************************************
228 * Core slab cache functions
229 *******************************************************************/
230
231int slab_is_available(void)
232{
233 return slab_state >= UP;
234}
235
236static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
237{
Christoph Lameter81819f02007-05-06 14:49:36 -0700238 return s->node[node];
Christoph Lameter81819f02007-05-06 14:49:36 -0700239}
240
Christoph Lameter6446faa2008-02-15 23:45:26 -0800241/* Verify that a pointer has an address that is valid within a slab page */
Christoph Lameter02cbc872007-05-09 02:32:43 -0700242static inline int check_valid_pointer(struct kmem_cache *s,
243 struct page *page, const void *object)
244{
245 void *base;
246
Christoph Lametera973e9d2008-03-01 13:40:44 -0800247 if (!object)
Christoph Lameter02cbc872007-05-09 02:32:43 -0700248 return 1;
249
Christoph Lametera973e9d2008-03-01 13:40:44 -0800250 base = page_address(page);
Christoph Lameter39b26462008-04-14 19:11:30 +0300251 if (object < base || object >= base + page->objects * s->size ||
Christoph Lameter02cbc872007-05-09 02:32:43 -0700252 (object - base) % s->size) {
253 return 0;
254 }
255
256 return 1;
257}
258
Christoph Lameter7656c722007-05-09 02:32:40 -0700259static inline void *get_freepointer(struct kmem_cache *s, void *object)
260{
261 return *(void **)(object + s->offset);
262}
263
Christoph Lameter1393d9a2011-05-16 15:26:08 -0500264static inline void *get_freepointer_safe(struct kmem_cache *s, void *object)
265{
266 void *p;
267
268#ifdef CONFIG_DEBUG_PAGEALLOC
269 probe_kernel_read(&p, (void **)(object + s->offset), sizeof(p));
270#else
271 p = get_freepointer(s, object);
272#endif
273 return p;
274}
275
Christoph Lameter7656c722007-05-09 02:32:40 -0700276static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp)
277{
278 *(void **)(object + s->offset) = fp;
279}
280
281/* Loop over all objects in a slab */
Christoph Lameter224a88b2008-04-14 19:11:31 +0300282#define for_each_object(__p, __s, __addr, __objects) \
283 for (__p = (__addr); __p < (__addr) + (__objects) * (__s)->size;\
Christoph Lameter7656c722007-05-09 02:32:40 -0700284 __p += (__s)->size)
285
Christoph Lameter7656c722007-05-09 02:32:40 -0700286/* Determine object index from a given position */
287static inline int slab_index(void *p, struct kmem_cache *s, void *addr)
288{
289 return (p - addr) / s->size;
290}
291
Mariusz Kozlowskid71f6062011-02-26 20:10:26 +0100292static inline size_t slab_ksize(const struct kmem_cache *s)
293{
294#ifdef CONFIG_SLUB_DEBUG
295 /*
296 * Debugging requires use of the padding between object
297 * and whatever may come after it.
298 */
299 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
300 return s->objsize;
301
302#endif
303 /*
304 * If we have the need to store the freelist pointer
305 * back there or track user information then we can
306 * only use the space before that information.
307 */
308 if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER))
309 return s->inuse;
310 /*
311 * Else we can use all the padding etc for the allocation
312 */
313 return s->size;
314}
315
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800316static inline int order_objects(int order, unsigned long size, int reserved)
317{
318 return ((PAGE_SIZE << order) - reserved) / size;
319}
320
Christoph Lameter834f3d12008-04-14 19:11:31 +0300321static inline struct kmem_cache_order_objects oo_make(int order,
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800322 unsigned long size, int reserved)
Christoph Lameter834f3d12008-04-14 19:11:31 +0300323{
324 struct kmem_cache_order_objects x = {
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800325 (order << OO_SHIFT) + order_objects(order, size, reserved)
Christoph Lameter834f3d12008-04-14 19:11:31 +0300326 };
327
328 return x;
329}
330
331static inline int oo_order(struct kmem_cache_order_objects x)
332{
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400333 return x.x >> OO_SHIFT;
Christoph Lameter834f3d12008-04-14 19:11:31 +0300334}
335
336static inline int oo_objects(struct kmem_cache_order_objects x)
337{
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400338 return x.x & OO_MASK;
Christoph Lameter834f3d12008-04-14 19:11:31 +0300339}
340
Christoph Lameter41ecc552007-05-09 02:32:44 -0700341#ifdef CONFIG_SLUB_DEBUG
342/*
Christoph Lameter5f80b132011-04-15 14:48:13 -0500343 * Determine a map of object in use on a page.
344 *
345 * Slab lock or node listlock must be held to guarantee that the page does
346 * not vanish from under us.
347 */
348static void get_map(struct kmem_cache *s, struct page *page, unsigned long *map)
349{
350 void *p;
351 void *addr = page_address(page);
352
353 for (p = page->freelist; p; p = get_freepointer(s, p))
354 set_bit(slab_index(p, s, addr), map);
355}
356
Christoph Lameter41ecc552007-05-09 02:32:44 -0700357/*
358 * Debug settings:
359 */
Christoph Lameterf0630ff2007-07-15 23:38:14 -0700360#ifdef CONFIG_SLUB_DEBUG_ON
361static int slub_debug = DEBUG_DEFAULT_FLAGS;
362#else
Christoph Lameter41ecc552007-05-09 02:32:44 -0700363static int slub_debug;
Christoph Lameterf0630ff2007-07-15 23:38:14 -0700364#endif
Christoph Lameter41ecc552007-05-09 02:32:44 -0700365
366static char *slub_debug_slabs;
David Rientjesfa5ec8a2009-07-07 00:14:14 -0700367static int disable_higher_order_debug;
Christoph Lameter41ecc552007-05-09 02:32:44 -0700368
Christoph Lameter7656c722007-05-09 02:32:40 -0700369/*
Christoph Lameter81819f02007-05-06 14:49:36 -0700370 * Object debugging
371 */
372static void print_section(char *text, u8 *addr, unsigned int length)
373{
374 int i, offset;
375 int newline = 1;
376 char ascii[17];
377
378 ascii[16] = 0;
379
380 for (i = 0; i < length; i++) {
381 if (newline) {
Christoph Lameter24922682007-07-17 04:03:18 -0700382 printk(KERN_ERR "%8s 0x%p: ", text, addr + i);
Christoph Lameter81819f02007-05-06 14:49:36 -0700383 newline = 0;
384 }
Pekka Enberg06428782008-01-07 23:20:27 -0800385 printk(KERN_CONT " %02x", addr[i]);
Christoph Lameter81819f02007-05-06 14:49:36 -0700386 offset = i % 16;
387 ascii[offset] = isgraph(addr[i]) ? addr[i] : '.';
388 if (offset == 15) {
Pekka Enberg06428782008-01-07 23:20:27 -0800389 printk(KERN_CONT " %s\n", ascii);
Christoph Lameter81819f02007-05-06 14:49:36 -0700390 newline = 1;
391 }
392 }
393 if (!newline) {
394 i %= 16;
395 while (i < 16) {
Pekka Enberg06428782008-01-07 23:20:27 -0800396 printk(KERN_CONT " ");
Christoph Lameter81819f02007-05-06 14:49:36 -0700397 ascii[i] = ' ';
398 i++;
399 }
Pekka Enberg06428782008-01-07 23:20:27 -0800400 printk(KERN_CONT " %s\n", ascii);
Christoph Lameter81819f02007-05-06 14:49:36 -0700401 }
402}
403
Christoph Lameter81819f02007-05-06 14:49:36 -0700404static struct track *get_track(struct kmem_cache *s, void *object,
405 enum track_item alloc)
406{
407 struct track *p;
408
409 if (s->offset)
410 p = object + s->offset + sizeof(void *);
411 else
412 p = object + s->inuse;
413
414 return p + alloc;
415}
416
417static void set_track(struct kmem_cache *s, void *object,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300418 enum track_item alloc, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -0700419{
Akinobu Mita1a00df42009-03-07 00:36:21 +0900420 struct track *p = get_track(s, object, alloc);
Christoph Lameter81819f02007-05-06 14:49:36 -0700421
Christoph Lameter81819f02007-05-06 14:49:36 -0700422 if (addr) {
423 p->addr = addr;
424 p->cpu = smp_processor_id();
Alexey Dobriyan88e4ccf2008-06-23 02:58:37 +0400425 p->pid = current->pid;
Christoph Lameter81819f02007-05-06 14:49:36 -0700426 p->when = jiffies;
427 } else
428 memset(p, 0, sizeof(struct track));
429}
430
Christoph Lameter81819f02007-05-06 14:49:36 -0700431static void init_tracking(struct kmem_cache *s, void *object)
432{
Christoph Lameter24922682007-07-17 04:03:18 -0700433 if (!(s->flags & SLAB_STORE_USER))
434 return;
435
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300436 set_track(s, object, TRACK_FREE, 0UL);
437 set_track(s, object, TRACK_ALLOC, 0UL);
Christoph Lameter81819f02007-05-06 14:49:36 -0700438}
439
440static void print_track(const char *s, struct track *t)
441{
442 if (!t->addr)
443 return;
444
Linus Torvalds7daf7052008-07-14 12:12:53 -0700445 printk(KERN_ERR "INFO: %s in %pS age=%lu cpu=%u pid=%d\n",
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300446 s, (void *)t->addr, jiffies - t->when, t->cpu, t->pid);
Christoph Lameter81819f02007-05-06 14:49:36 -0700447}
448
Christoph Lameter24922682007-07-17 04:03:18 -0700449static void print_tracking(struct kmem_cache *s, void *object)
450{
451 if (!(s->flags & SLAB_STORE_USER))
452 return;
453
454 print_track("Allocated", get_track(s, object, TRACK_ALLOC));
455 print_track("Freed", get_track(s, object, TRACK_FREE));
456}
457
458static void print_page_info(struct page *page)
459{
Christoph Lameter39b26462008-04-14 19:11:30 +0300460 printk(KERN_ERR "INFO: Slab 0x%p objects=%u used=%u fp=0x%p flags=0x%04lx\n",
461 page, page->objects, page->inuse, page->freelist, page->flags);
Christoph Lameter24922682007-07-17 04:03:18 -0700462
463}
464
465static void slab_bug(struct kmem_cache *s, char *fmt, ...)
466{
467 va_list args;
468 char buf[100];
469
470 va_start(args, fmt);
471 vsnprintf(buf, sizeof(buf), fmt, args);
472 va_end(args);
473 printk(KERN_ERR "========================================"
474 "=====================================\n");
475 printk(KERN_ERR "BUG %s: %s\n", s->name, buf);
476 printk(KERN_ERR "----------------------------------------"
477 "-------------------------------------\n\n");
478}
479
480static void slab_fix(struct kmem_cache *s, char *fmt, ...)
481{
482 va_list args;
483 char buf[100];
484
485 va_start(args, fmt);
486 vsnprintf(buf, sizeof(buf), fmt, args);
487 va_end(args);
488 printk(KERN_ERR "FIX %s: %s\n", s->name, buf);
489}
490
491static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p)
Christoph Lameter81819f02007-05-06 14:49:36 -0700492{
493 unsigned int off; /* Offset of last byte */
Christoph Lametera973e9d2008-03-01 13:40:44 -0800494 u8 *addr = page_address(page);
Christoph Lameter24922682007-07-17 04:03:18 -0700495
496 print_tracking(s, p);
497
498 print_page_info(page);
499
500 printk(KERN_ERR "INFO: Object 0x%p @offset=%tu fp=0x%p\n\n",
501 p, p - addr, get_freepointer(s, p));
502
503 if (p > addr + 16)
504 print_section("Bytes b4", p - 16, 16);
505
Pekka Enberg0ebd6522008-07-19 14:17:22 +0300506 print_section("Object", p, min_t(unsigned long, s->objsize, PAGE_SIZE));
Christoph Lameter81819f02007-05-06 14:49:36 -0700507
508 if (s->flags & SLAB_RED_ZONE)
509 print_section("Redzone", p + s->objsize,
510 s->inuse - s->objsize);
511
Christoph Lameter81819f02007-05-06 14:49:36 -0700512 if (s->offset)
513 off = s->offset + sizeof(void *);
514 else
515 off = s->inuse;
516
Christoph Lameter24922682007-07-17 04:03:18 -0700517 if (s->flags & SLAB_STORE_USER)
Christoph Lameter81819f02007-05-06 14:49:36 -0700518 off += 2 * sizeof(struct track);
Christoph Lameter81819f02007-05-06 14:49:36 -0700519
520 if (off != s->size)
521 /* Beginning of the filler is the free pointer */
Christoph Lameter24922682007-07-17 04:03:18 -0700522 print_section("Padding", p + off, s->size - off);
523
524 dump_stack();
Christoph Lameter81819f02007-05-06 14:49:36 -0700525}
526
527static void object_err(struct kmem_cache *s, struct page *page,
528 u8 *object, char *reason)
529{
Christoph Lameter3dc50632008-04-23 12:28:01 -0700530 slab_bug(s, "%s", reason);
Christoph Lameter24922682007-07-17 04:03:18 -0700531 print_trailer(s, page, object);
Christoph Lameter81819f02007-05-06 14:49:36 -0700532}
533
Christoph Lameter24922682007-07-17 04:03:18 -0700534static void slab_err(struct kmem_cache *s, struct page *page, char *fmt, ...)
Christoph Lameter81819f02007-05-06 14:49:36 -0700535{
536 va_list args;
537 char buf[100];
538
Christoph Lameter24922682007-07-17 04:03:18 -0700539 va_start(args, fmt);
540 vsnprintf(buf, sizeof(buf), fmt, args);
Christoph Lameter81819f02007-05-06 14:49:36 -0700541 va_end(args);
Christoph Lameter3dc50632008-04-23 12:28:01 -0700542 slab_bug(s, "%s", buf);
Christoph Lameter24922682007-07-17 04:03:18 -0700543 print_page_info(page);
Christoph Lameter81819f02007-05-06 14:49:36 -0700544 dump_stack();
545}
546
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500547static void init_object(struct kmem_cache *s, void *object, u8 val)
Christoph Lameter81819f02007-05-06 14:49:36 -0700548{
549 u8 *p = object;
550
551 if (s->flags & __OBJECT_POISON) {
552 memset(p, POISON_FREE, s->objsize - 1);
Pekka Enberg06428782008-01-07 23:20:27 -0800553 p[s->objsize - 1] = POISON_END;
Christoph Lameter81819f02007-05-06 14:49:36 -0700554 }
555
556 if (s->flags & SLAB_RED_ZONE)
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500557 memset(p + s->objsize, val, s->inuse - s->objsize);
Christoph Lameter81819f02007-05-06 14:49:36 -0700558}
559
Christoph Lameter24922682007-07-17 04:03:18 -0700560static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes)
Christoph Lameter81819f02007-05-06 14:49:36 -0700561{
562 while (bytes) {
563 if (*start != (u8)value)
Christoph Lameter24922682007-07-17 04:03:18 -0700564 return start;
Christoph Lameter81819f02007-05-06 14:49:36 -0700565 start++;
566 bytes--;
567 }
Christoph Lameter24922682007-07-17 04:03:18 -0700568 return NULL;
569}
570
571static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
572 void *from, void *to)
573{
574 slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data);
575 memset(from, data, to - from);
576}
577
578static int check_bytes_and_report(struct kmem_cache *s, struct page *page,
579 u8 *object, char *what,
Pekka Enberg06428782008-01-07 23:20:27 -0800580 u8 *start, unsigned int value, unsigned int bytes)
Christoph Lameter24922682007-07-17 04:03:18 -0700581{
582 u8 *fault;
583 u8 *end;
584
585 fault = check_bytes(start, value, bytes);
586 if (!fault)
587 return 1;
588
589 end = start + bytes;
590 while (end > fault && end[-1] == value)
591 end--;
592
593 slab_bug(s, "%s overwritten", what);
594 printk(KERN_ERR "INFO: 0x%p-0x%p. First byte 0x%x instead of 0x%x\n",
595 fault, end - 1, fault[0], value);
596 print_trailer(s, page, object);
597
598 restore_bytes(s, what, value, fault, end);
599 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700600}
601
Christoph Lameter81819f02007-05-06 14:49:36 -0700602/*
603 * Object layout:
604 *
605 * object address
606 * Bytes of the object to be managed.
607 * If the freepointer may overlay the object then the free
608 * pointer is the first word of the object.
Christoph Lameter672bba32007-05-09 02:32:39 -0700609 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700610 * Poisoning uses 0x6b (POISON_FREE) and the last byte is
611 * 0xa5 (POISON_END)
612 *
613 * object + s->objsize
614 * Padding to reach word boundary. This is also used for Redzoning.
Christoph Lameter672bba32007-05-09 02:32:39 -0700615 * Padding is extended by another word if Redzoning is enabled and
616 * objsize == inuse.
617 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700618 * We fill with 0xbb (RED_INACTIVE) for inactive objects and with
619 * 0xcc (RED_ACTIVE) for objects in use.
620 *
621 * object + s->inuse
Christoph Lameter672bba32007-05-09 02:32:39 -0700622 * Meta data starts here.
623 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700624 * A. Free pointer (if we cannot overwrite object on free)
625 * B. Tracking data for SLAB_STORE_USER
Christoph Lameter672bba32007-05-09 02:32:39 -0700626 * C. Padding to reach required alignment boundary or at mininum
Christoph Lameter6446faa2008-02-15 23:45:26 -0800627 * one word if debugging is on to be able to detect writes
Christoph Lameter672bba32007-05-09 02:32:39 -0700628 * before the word boundary.
629 *
630 * Padding is done using 0x5a (POISON_INUSE)
Christoph Lameter81819f02007-05-06 14:49:36 -0700631 *
632 * object + s->size
Christoph Lameter672bba32007-05-09 02:32:39 -0700633 * Nothing is used beyond s->size.
Christoph Lameter81819f02007-05-06 14:49:36 -0700634 *
Christoph Lameter672bba32007-05-09 02:32:39 -0700635 * If slabcaches are merged then the objsize and inuse boundaries are mostly
636 * ignored. And therefore no slab options that rely on these boundaries
Christoph Lameter81819f02007-05-06 14:49:36 -0700637 * may be used with merged slabcaches.
638 */
639
Christoph Lameter81819f02007-05-06 14:49:36 -0700640static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p)
641{
642 unsigned long off = s->inuse; /* The end of info */
643
644 if (s->offset)
645 /* Freepointer is placed after the object. */
646 off += sizeof(void *);
647
648 if (s->flags & SLAB_STORE_USER)
649 /* We also have user information there */
650 off += 2 * sizeof(struct track);
651
652 if (s->size == off)
653 return 1;
654
Christoph Lameter24922682007-07-17 04:03:18 -0700655 return check_bytes_and_report(s, page, p, "Object padding",
656 p + off, POISON_INUSE, s->size - off);
Christoph Lameter81819f02007-05-06 14:49:36 -0700657}
658
Christoph Lameter39b26462008-04-14 19:11:30 +0300659/* Check the pad bytes at the end of a slab page */
Christoph Lameter81819f02007-05-06 14:49:36 -0700660static int slab_pad_check(struct kmem_cache *s, struct page *page)
661{
Christoph Lameter24922682007-07-17 04:03:18 -0700662 u8 *start;
663 u8 *fault;
664 u8 *end;
665 int length;
666 int remainder;
Christoph Lameter81819f02007-05-06 14:49:36 -0700667
668 if (!(s->flags & SLAB_POISON))
669 return 1;
670
Christoph Lametera973e9d2008-03-01 13:40:44 -0800671 start = page_address(page);
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800672 length = (PAGE_SIZE << compound_order(page)) - s->reserved;
Christoph Lameter39b26462008-04-14 19:11:30 +0300673 end = start + length;
674 remainder = length % s->size;
Christoph Lameter81819f02007-05-06 14:49:36 -0700675 if (!remainder)
676 return 1;
677
Christoph Lameter39b26462008-04-14 19:11:30 +0300678 fault = check_bytes(end - remainder, POISON_INUSE, remainder);
Christoph Lameter24922682007-07-17 04:03:18 -0700679 if (!fault)
680 return 1;
681 while (end > fault && end[-1] == POISON_INUSE)
682 end--;
683
684 slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1);
Christoph Lameter39b26462008-04-14 19:11:30 +0300685 print_section("Padding", end - remainder, remainder);
Christoph Lameter24922682007-07-17 04:03:18 -0700686
Eric Dumazet8a3d2712009-09-03 16:08:06 +0200687 restore_bytes(s, "slab padding", POISON_INUSE, end - remainder, end);
Christoph Lameter24922682007-07-17 04:03:18 -0700688 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700689}
690
691static int check_object(struct kmem_cache *s, struct page *page,
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500692 void *object, u8 val)
Christoph Lameter81819f02007-05-06 14:49:36 -0700693{
694 u8 *p = object;
695 u8 *endobject = object + s->objsize;
696
697 if (s->flags & SLAB_RED_ZONE) {
Christoph Lameter24922682007-07-17 04:03:18 -0700698 if (!check_bytes_and_report(s, page, object, "Redzone",
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500699 endobject, val, s->inuse - s->objsize))
Christoph Lameter81819f02007-05-06 14:49:36 -0700700 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700701 } else {
Ingo Molnar3adbefe2008-02-05 17:57:39 -0800702 if ((s->flags & SLAB_POISON) && s->objsize < s->inuse) {
703 check_bytes_and_report(s, page, p, "Alignment padding",
704 endobject, POISON_INUSE, s->inuse - s->objsize);
705 }
Christoph Lameter81819f02007-05-06 14:49:36 -0700706 }
707
708 if (s->flags & SLAB_POISON) {
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500709 if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) &&
Christoph Lameter24922682007-07-17 04:03:18 -0700710 (!check_bytes_and_report(s, page, p, "Poison", p,
711 POISON_FREE, s->objsize - 1) ||
712 !check_bytes_and_report(s, page, p, "Poison",
Pekka Enberg06428782008-01-07 23:20:27 -0800713 p + s->objsize - 1, POISON_END, 1)))
Christoph Lameter81819f02007-05-06 14:49:36 -0700714 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700715 /*
716 * check_pad_bytes cleans up on its own.
717 */
718 check_pad_bytes(s, page, p);
719 }
720
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500721 if (!s->offset && val == SLUB_RED_ACTIVE)
Christoph Lameter81819f02007-05-06 14:49:36 -0700722 /*
723 * Object and freepointer overlap. Cannot check
724 * freepointer while object is allocated.
725 */
726 return 1;
727
728 /* Check free pointer validity */
729 if (!check_valid_pointer(s, page, get_freepointer(s, p))) {
730 object_err(s, page, p, "Freepointer corrupt");
731 /*
Nick Andrew9f6c708e2008-12-05 14:08:08 +1100732 * No choice but to zap it and thus lose the remainder
Christoph Lameter81819f02007-05-06 14:49:36 -0700733 * of the free objects in this slab. May cause
Christoph Lameter672bba32007-05-09 02:32:39 -0700734 * another error because the object count is now wrong.
Christoph Lameter81819f02007-05-06 14:49:36 -0700735 */
Christoph Lametera973e9d2008-03-01 13:40:44 -0800736 set_freepointer(s, p, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -0700737 return 0;
738 }
739 return 1;
740}
741
742static int check_slab(struct kmem_cache *s, struct page *page)
743{
Christoph Lameter39b26462008-04-14 19:11:30 +0300744 int maxobj;
745
Christoph Lameter81819f02007-05-06 14:49:36 -0700746 VM_BUG_ON(!irqs_disabled());
747
748 if (!PageSlab(page)) {
Christoph Lameter24922682007-07-17 04:03:18 -0700749 slab_err(s, page, "Not a valid slab page");
Christoph Lameter81819f02007-05-06 14:49:36 -0700750 return 0;
751 }
Christoph Lameter39b26462008-04-14 19:11:30 +0300752
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800753 maxobj = order_objects(compound_order(page), s->size, s->reserved);
Christoph Lameter39b26462008-04-14 19:11:30 +0300754 if (page->objects > maxobj) {
755 slab_err(s, page, "objects %u > max %u",
756 s->name, page->objects, maxobj);
757 return 0;
758 }
759 if (page->inuse > page->objects) {
Christoph Lameter24922682007-07-17 04:03:18 -0700760 slab_err(s, page, "inuse %u > max %u",
Christoph Lameter39b26462008-04-14 19:11:30 +0300761 s->name, page->inuse, page->objects);
Christoph Lameter81819f02007-05-06 14:49:36 -0700762 return 0;
763 }
764 /* Slab_pad_check fixes things up after itself */
765 slab_pad_check(s, page);
766 return 1;
767}
768
769/*
Christoph Lameter672bba32007-05-09 02:32:39 -0700770 * Determine if a certain object on a page is on the freelist. Must hold the
771 * slab lock to guarantee that the chains are in a consistent state.
Christoph Lameter81819f02007-05-06 14:49:36 -0700772 */
773static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
774{
775 int nr = 0;
776 void *fp = page->freelist;
777 void *object = NULL;
Christoph Lameter224a88b2008-04-14 19:11:31 +0300778 unsigned long max_objects;
Christoph Lameter81819f02007-05-06 14:49:36 -0700779
Christoph Lameter39b26462008-04-14 19:11:30 +0300780 while (fp && nr <= page->objects) {
Christoph Lameter81819f02007-05-06 14:49:36 -0700781 if (fp == search)
782 return 1;
783 if (!check_valid_pointer(s, page, fp)) {
784 if (object) {
785 object_err(s, page, object,
786 "Freechain corrupt");
Christoph Lametera973e9d2008-03-01 13:40:44 -0800787 set_freepointer(s, object, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -0700788 break;
789 } else {
Christoph Lameter24922682007-07-17 04:03:18 -0700790 slab_err(s, page, "Freepointer corrupt");
Christoph Lametera973e9d2008-03-01 13:40:44 -0800791 page->freelist = NULL;
Christoph Lameter39b26462008-04-14 19:11:30 +0300792 page->inuse = page->objects;
Christoph Lameter24922682007-07-17 04:03:18 -0700793 slab_fix(s, "Freelist cleared");
Christoph Lameter81819f02007-05-06 14:49:36 -0700794 return 0;
795 }
796 break;
797 }
798 object = fp;
799 fp = get_freepointer(s, object);
800 nr++;
801 }
802
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800803 max_objects = order_objects(compound_order(page), s->size, s->reserved);
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400804 if (max_objects > MAX_OBJS_PER_PAGE)
805 max_objects = MAX_OBJS_PER_PAGE;
Christoph Lameter224a88b2008-04-14 19:11:31 +0300806
807 if (page->objects != max_objects) {
808 slab_err(s, page, "Wrong number of objects. Found %d but "
809 "should be %d", page->objects, max_objects);
810 page->objects = max_objects;
811 slab_fix(s, "Number of objects adjusted.");
812 }
Christoph Lameter39b26462008-04-14 19:11:30 +0300813 if (page->inuse != page->objects - nr) {
Christoph Lameter70d71222007-05-06 14:49:47 -0700814 slab_err(s, page, "Wrong object count. Counter is %d but "
Christoph Lameter39b26462008-04-14 19:11:30 +0300815 "counted were %d", page->inuse, page->objects - nr);
816 page->inuse = page->objects - nr;
Christoph Lameter24922682007-07-17 04:03:18 -0700817 slab_fix(s, "Object count adjusted.");
Christoph Lameter81819f02007-05-06 14:49:36 -0700818 }
819 return search == NULL;
820}
821
Christoph Lameter0121c6192008-04-29 16:11:12 -0700822static void trace(struct kmem_cache *s, struct page *page, void *object,
823 int alloc)
Christoph Lameter3ec09742007-05-16 22:11:00 -0700824{
825 if (s->flags & SLAB_TRACE) {
826 printk(KERN_INFO "TRACE %s %s 0x%p inuse=%d fp=0x%p\n",
827 s->name,
828 alloc ? "alloc" : "free",
829 object, page->inuse,
830 page->freelist);
831
832 if (!alloc)
833 print_section("Object", (void *)object, s->objsize);
834
835 dump_stack();
836 }
837}
838
Christoph Lameter643b1132007-05-06 14:49:42 -0700839/*
Christoph Lameterc016b0b2010-08-20 12:37:16 -0500840 * Hooks for other subsystems that check memory allocations. In a typical
841 * production configuration these hooks all should produce no code at all.
842 */
843static inline int slab_pre_alloc_hook(struct kmem_cache *s, gfp_t flags)
844{
Christoph Lameterc1d50832010-08-20 12:37:17 -0500845 flags &= gfp_allowed_mask;
Christoph Lameterc016b0b2010-08-20 12:37:16 -0500846 lockdep_trace_alloc(flags);
847 might_sleep_if(flags & __GFP_WAIT);
848
849 return should_failslab(s->objsize, flags, s->flags);
850}
851
852static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags, void *object)
853{
Christoph Lameterc1d50832010-08-20 12:37:17 -0500854 flags &= gfp_allowed_mask;
Eric Dumazetb3d41882011-02-14 18:35:22 +0100855 kmemcheck_slab_alloc(s, flags, object, slab_ksize(s));
Christoph Lameterc016b0b2010-08-20 12:37:16 -0500856 kmemleak_alloc_recursive(object, s->objsize, 1, s->flags, flags);
857}
858
859static inline void slab_free_hook(struct kmem_cache *s, void *x)
860{
861 kmemleak_free_recursive(x, s->flags);
Christoph Lameterc016b0b2010-08-20 12:37:16 -0500862
Christoph Lameterd3f661d2011-02-25 11:38:52 -0600863 /*
864 * Trouble is that we may no longer disable interupts in the fast path
865 * So in order to make the debug calls that expect irqs to be
866 * disabled we need to disable interrupts temporarily.
867 */
868#if defined(CONFIG_KMEMCHECK) || defined(CONFIG_LOCKDEP)
869 {
870 unsigned long flags;
871
872 local_irq_save(flags);
873 kmemcheck_slab_free(s, x, s->objsize);
874 debug_check_no_locks_freed(x, s->objsize);
Christoph Lameterd3f661d2011-02-25 11:38:52 -0600875 local_irq_restore(flags);
876 }
877#endif
Thomas Gleixnerf9b615d2011-03-24 21:26:46 +0200878 if (!(s->flags & SLAB_DEBUG_OBJECTS))
879 debug_check_no_obj_freed(x, s->objsize);
Christoph Lameterc016b0b2010-08-20 12:37:16 -0500880}
881
882/*
Christoph Lameter672bba32007-05-09 02:32:39 -0700883 * Tracking of fully allocated slabs for debugging purposes.
Christoph Lameter643b1132007-05-06 14:49:42 -0700884 */
Christoph Lametere95eed52007-05-06 14:49:44 -0700885static void add_full(struct kmem_cache_node *n, struct page *page)
Christoph Lameter643b1132007-05-06 14:49:42 -0700886{
Christoph Lameter643b1132007-05-06 14:49:42 -0700887 spin_lock(&n->list_lock);
888 list_add(&page->lru, &n->full);
889 spin_unlock(&n->list_lock);
890}
891
892static void remove_full(struct kmem_cache *s, struct page *page)
893{
894 struct kmem_cache_node *n;
895
896 if (!(s->flags & SLAB_STORE_USER))
897 return;
898
899 n = get_node(s, page_to_nid(page));
900
901 spin_lock(&n->list_lock);
902 list_del(&page->lru);
903 spin_unlock(&n->list_lock);
904}
905
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300906/* Tracking of the number of slabs for debugging purposes */
907static inline unsigned long slabs_node(struct kmem_cache *s, int node)
908{
909 struct kmem_cache_node *n = get_node(s, node);
910
911 return atomic_long_read(&n->nr_slabs);
912}
913
Alexander Beregalov26c02cf2009-06-11 14:08:48 +0400914static inline unsigned long node_nr_slabs(struct kmem_cache_node *n)
915{
916 return atomic_long_read(&n->nr_slabs);
917}
918
Christoph Lameter205ab992008-04-14 19:11:40 +0300919static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects)
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300920{
921 struct kmem_cache_node *n = get_node(s, node);
922
923 /*
924 * May be called early in order to allocate a slab for the
925 * kmem_cache_node structure. Solve the chicken-egg
926 * dilemma by deferring the increment of the count during
927 * bootstrap (see early_kmem_cache_node_alloc).
928 */
Christoph Lameter7340cc82010-09-28 08:10:26 -0500929 if (n) {
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300930 atomic_long_inc(&n->nr_slabs);
Christoph Lameter205ab992008-04-14 19:11:40 +0300931 atomic_long_add(objects, &n->total_objects);
932 }
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300933}
Christoph Lameter205ab992008-04-14 19:11:40 +0300934static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects)
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300935{
936 struct kmem_cache_node *n = get_node(s, node);
937
938 atomic_long_dec(&n->nr_slabs);
Christoph Lameter205ab992008-04-14 19:11:40 +0300939 atomic_long_sub(objects, &n->total_objects);
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300940}
941
942/* Object debug checks for alloc/free paths */
Christoph Lameter3ec09742007-05-16 22:11:00 -0700943static void setup_object_debug(struct kmem_cache *s, struct page *page,
944 void *object)
945{
946 if (!(s->flags & (SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON)))
947 return;
948
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500949 init_object(s, object, SLUB_RED_INACTIVE);
Christoph Lameter3ec09742007-05-16 22:11:00 -0700950 init_tracking(s, object);
951}
952
Christoph Lameter15370662010-08-20 12:37:12 -0500953static noinline int alloc_debug_processing(struct kmem_cache *s, struct page *page,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300954 void *object, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -0700955{
956 if (!check_slab(s, page))
957 goto bad;
958
Christoph Lameterd692ef62008-02-15 23:45:24 -0800959 if (!on_freelist(s, page, object)) {
Christoph Lameter24922682007-07-17 04:03:18 -0700960 object_err(s, page, object, "Object already allocated");
Christoph Lameter70d71222007-05-06 14:49:47 -0700961 goto bad;
Christoph Lameter81819f02007-05-06 14:49:36 -0700962 }
963
964 if (!check_valid_pointer(s, page, object)) {
965 object_err(s, page, object, "Freelist Pointer check fails");
Christoph Lameter70d71222007-05-06 14:49:47 -0700966 goto bad;
Christoph Lameter81819f02007-05-06 14:49:36 -0700967 }
968
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500969 if (!check_object(s, page, object, SLUB_RED_INACTIVE))
Christoph Lameter81819f02007-05-06 14:49:36 -0700970 goto bad;
Christoph Lameter81819f02007-05-06 14:49:36 -0700971
Christoph Lameter3ec09742007-05-16 22:11:00 -0700972 /* Success perform special debug activities for allocs */
973 if (s->flags & SLAB_STORE_USER)
974 set_track(s, object, TRACK_ALLOC, addr);
975 trace(s, page, object, 1);
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500976 init_object(s, object, SLUB_RED_ACTIVE);
Christoph Lameter81819f02007-05-06 14:49:36 -0700977 return 1;
Christoph Lameter3ec09742007-05-16 22:11:00 -0700978
Christoph Lameter81819f02007-05-06 14:49:36 -0700979bad:
980 if (PageSlab(page)) {
981 /*
982 * If this is a slab page then lets do the best we can
983 * to avoid issues in the future. Marking all objects
Christoph Lameter672bba32007-05-09 02:32:39 -0700984 * as used avoids touching the remaining objects.
Christoph Lameter81819f02007-05-06 14:49:36 -0700985 */
Christoph Lameter24922682007-07-17 04:03:18 -0700986 slab_fix(s, "Marking all objects used");
Christoph Lameter39b26462008-04-14 19:11:30 +0300987 page->inuse = page->objects;
Christoph Lametera973e9d2008-03-01 13:40:44 -0800988 page->freelist = NULL;
Christoph Lameter81819f02007-05-06 14:49:36 -0700989 }
990 return 0;
991}
992
Christoph Lameter15370662010-08-20 12:37:12 -0500993static noinline int free_debug_processing(struct kmem_cache *s,
994 struct page *page, void *object, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -0700995{
996 if (!check_slab(s, page))
997 goto fail;
998
999 if (!check_valid_pointer(s, page, object)) {
Christoph Lameter70d71222007-05-06 14:49:47 -07001000 slab_err(s, page, "Invalid object pointer 0x%p", object);
Christoph Lameter81819f02007-05-06 14:49:36 -07001001 goto fail;
1002 }
1003
1004 if (on_freelist(s, page, object)) {
Christoph Lameter24922682007-07-17 04:03:18 -07001005 object_err(s, page, object, "Object already free");
Christoph Lameter81819f02007-05-06 14:49:36 -07001006 goto fail;
1007 }
1008
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001009 if (!check_object(s, page, object, SLUB_RED_ACTIVE))
Christoph Lameter81819f02007-05-06 14:49:36 -07001010 return 0;
1011
1012 if (unlikely(s != page->slab)) {
Ingo Molnar3adbefe2008-02-05 17:57:39 -08001013 if (!PageSlab(page)) {
Christoph Lameter70d71222007-05-06 14:49:47 -07001014 slab_err(s, page, "Attempt to free object(0x%p) "
1015 "outside of slab", object);
Ingo Molnar3adbefe2008-02-05 17:57:39 -08001016 } else if (!page->slab) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001017 printk(KERN_ERR
Christoph Lameter70d71222007-05-06 14:49:47 -07001018 "SLUB <none>: no slab for object 0x%p.\n",
Christoph Lameter81819f02007-05-06 14:49:36 -07001019 object);
Christoph Lameter70d71222007-05-06 14:49:47 -07001020 dump_stack();
Pekka Enberg06428782008-01-07 23:20:27 -08001021 } else
Christoph Lameter24922682007-07-17 04:03:18 -07001022 object_err(s, page, object,
1023 "page slab pointer corrupt.");
Christoph Lameter81819f02007-05-06 14:49:36 -07001024 goto fail;
1025 }
Christoph Lameter3ec09742007-05-16 22:11:00 -07001026
1027 /* Special debug activities for freeing objects */
Andy Whitcroft8a380822008-07-23 21:27:18 -07001028 if (!PageSlubFrozen(page) && !page->freelist)
Christoph Lameter3ec09742007-05-16 22:11:00 -07001029 remove_full(s, page);
1030 if (s->flags & SLAB_STORE_USER)
1031 set_track(s, object, TRACK_FREE, addr);
1032 trace(s, page, object, 0);
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001033 init_object(s, object, SLUB_RED_INACTIVE);
Christoph Lameter81819f02007-05-06 14:49:36 -07001034 return 1;
Christoph Lameter3ec09742007-05-16 22:11:00 -07001035
Christoph Lameter81819f02007-05-06 14:49:36 -07001036fail:
Christoph Lameter24922682007-07-17 04:03:18 -07001037 slab_fix(s, "Object at 0x%p not freed", object);
Christoph Lameter81819f02007-05-06 14:49:36 -07001038 return 0;
1039}
1040
Christoph Lameter41ecc552007-05-09 02:32:44 -07001041static int __init setup_slub_debug(char *str)
1042{
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001043 slub_debug = DEBUG_DEFAULT_FLAGS;
1044 if (*str++ != '=' || !*str)
1045 /*
1046 * No options specified. Switch on full debugging.
1047 */
1048 goto out;
Christoph Lameter41ecc552007-05-09 02:32:44 -07001049
1050 if (*str == ',')
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001051 /*
1052 * No options but restriction on slabs. This means full
1053 * debugging for slabs matching a pattern.
1054 */
1055 goto check_slabs;
1056
David Rientjesfa5ec8a2009-07-07 00:14:14 -07001057 if (tolower(*str) == 'o') {
1058 /*
1059 * Avoid enabling debugging on caches if its minimum order
1060 * would increase as a result.
1061 */
1062 disable_higher_order_debug = 1;
1063 goto out;
1064 }
1065
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001066 slub_debug = 0;
1067 if (*str == '-')
1068 /*
1069 * Switch off all debugging measures.
1070 */
1071 goto out;
1072
1073 /*
1074 * Determine which debug features should be switched on
1075 */
Pekka Enberg06428782008-01-07 23:20:27 -08001076 for (; *str && *str != ','; str++) {
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001077 switch (tolower(*str)) {
1078 case 'f':
1079 slub_debug |= SLAB_DEBUG_FREE;
1080 break;
1081 case 'z':
1082 slub_debug |= SLAB_RED_ZONE;
1083 break;
1084 case 'p':
1085 slub_debug |= SLAB_POISON;
1086 break;
1087 case 'u':
1088 slub_debug |= SLAB_STORE_USER;
1089 break;
1090 case 't':
1091 slub_debug |= SLAB_TRACE;
1092 break;
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +03001093 case 'a':
1094 slub_debug |= SLAB_FAILSLAB;
1095 break;
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001096 default:
1097 printk(KERN_ERR "slub_debug option '%c' "
Pekka Enberg06428782008-01-07 23:20:27 -08001098 "unknown. skipped\n", *str);
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001099 }
1100 }
1101
1102check_slabs:
1103 if (*str == ',')
Christoph Lameter41ecc552007-05-09 02:32:44 -07001104 slub_debug_slabs = str + 1;
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001105out:
Christoph Lameter41ecc552007-05-09 02:32:44 -07001106 return 1;
1107}
1108
1109__setup("slub_debug", setup_slub_debug);
1110
Christoph Lameterba0268a2007-09-11 15:24:11 -07001111static unsigned long kmem_cache_flags(unsigned long objsize,
1112 unsigned long flags, const char *name,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001113 void (*ctor)(void *))
Christoph Lameter41ecc552007-05-09 02:32:44 -07001114{
1115 /*
Christoph Lametere1533622008-02-15 23:45:24 -08001116 * Enable debugging if selected on the kernel commandline.
Christoph Lameter41ecc552007-05-09 02:32:44 -07001117 */
Christoph Lametere1533622008-02-15 23:45:24 -08001118 if (slub_debug && (!slub_debug_slabs ||
David Rientjes3de47212009-07-27 18:30:35 -07001119 !strncmp(slub_debug_slabs, name, strlen(slub_debug_slabs))))
1120 flags |= slub_debug;
Christoph Lameterba0268a2007-09-11 15:24:11 -07001121
1122 return flags;
Christoph Lameter41ecc552007-05-09 02:32:44 -07001123}
1124#else
Christoph Lameter3ec09742007-05-16 22:11:00 -07001125static inline void setup_object_debug(struct kmem_cache *s,
1126 struct page *page, void *object) {}
Christoph Lameter41ecc552007-05-09 02:32:44 -07001127
Christoph Lameter3ec09742007-05-16 22:11:00 -07001128static inline int alloc_debug_processing(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001129 struct page *page, void *object, unsigned long addr) { return 0; }
Christoph Lameter41ecc552007-05-09 02:32:44 -07001130
Christoph Lameter3ec09742007-05-16 22:11:00 -07001131static inline int free_debug_processing(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001132 struct page *page, void *object, unsigned long addr) { return 0; }
Christoph Lameter41ecc552007-05-09 02:32:44 -07001133
Christoph Lameter41ecc552007-05-09 02:32:44 -07001134static inline int slab_pad_check(struct kmem_cache *s, struct page *page)
1135 { return 1; }
1136static inline int check_object(struct kmem_cache *s, struct page *page,
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001137 void *object, u8 val) { return 1; }
Christoph Lameter3ec09742007-05-16 22:11:00 -07001138static inline void add_full(struct kmem_cache_node *n, struct page *page) {}
Christoph Lameterba0268a2007-09-11 15:24:11 -07001139static inline unsigned long kmem_cache_flags(unsigned long objsize,
1140 unsigned long flags, const char *name,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001141 void (*ctor)(void *))
Christoph Lameterba0268a2007-09-11 15:24:11 -07001142{
1143 return flags;
1144}
Christoph Lameter41ecc552007-05-09 02:32:44 -07001145#define slub_debug 0
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001146
Ingo Molnarfdaa45e2009-09-15 11:00:26 +02001147#define disable_higher_order_debug 0
1148
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001149static inline unsigned long slabs_node(struct kmem_cache *s, int node)
1150 { return 0; }
Alexander Beregalov26c02cf2009-06-11 14:08:48 +04001151static inline unsigned long node_nr_slabs(struct kmem_cache_node *n)
1152 { return 0; }
Christoph Lameter205ab992008-04-14 19:11:40 +03001153static inline void inc_slabs_node(struct kmem_cache *s, int node,
1154 int objects) {}
1155static inline void dec_slabs_node(struct kmem_cache *s, int node,
1156 int objects) {}
Christoph Lameter7d550c52010-08-25 14:07:16 -05001157
1158static inline int slab_pre_alloc_hook(struct kmem_cache *s, gfp_t flags)
1159 { return 0; }
1160
1161static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
1162 void *object) {}
1163
1164static inline void slab_free_hook(struct kmem_cache *s, void *x) {}
1165
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05001166#endif /* CONFIG_SLUB_DEBUG */
Christoph Lameter205ab992008-04-14 19:11:40 +03001167
Christoph Lameter81819f02007-05-06 14:49:36 -07001168/*
1169 * Slab allocation and freeing
1170 */
Christoph Lameter65c33762008-04-14 19:11:40 +03001171static inline struct page *alloc_slab_page(gfp_t flags, int node,
1172 struct kmem_cache_order_objects oo)
1173{
1174 int order = oo_order(oo);
1175
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001176 flags |= __GFP_NOTRACK;
1177
Christoph Lameter2154a332010-07-09 14:07:10 -05001178 if (node == NUMA_NO_NODE)
Christoph Lameter65c33762008-04-14 19:11:40 +03001179 return alloc_pages(flags, order);
1180 else
Minchan Kim6b65aaf2010-04-14 23:58:36 +09001181 return alloc_pages_exact_node(node, flags, order);
Christoph Lameter65c33762008-04-14 19:11:40 +03001182}
1183
Christoph Lameter81819f02007-05-06 14:49:36 -07001184static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
1185{
Pekka Enberg06428782008-01-07 23:20:27 -08001186 struct page *page;
Christoph Lameter834f3d12008-04-14 19:11:31 +03001187 struct kmem_cache_order_objects oo = s->oo;
Pekka Enbergba522702009-06-24 21:59:51 +03001188 gfp_t alloc_gfp;
Christoph Lameter81819f02007-05-06 14:49:36 -07001189
Christoph Lameterb7a49f02008-02-14 14:21:32 -08001190 flags |= s->allocflags;
Mel Gormane12ba742007-10-16 01:25:52 -07001191
Pekka Enbergba522702009-06-24 21:59:51 +03001192 /*
1193 * Let the initial higher-order allocation fail under memory pressure
1194 * so we fall-back to the minimum order allocation.
1195 */
1196 alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL;
1197
1198 page = alloc_slab_page(alloc_gfp, node, oo);
Christoph Lameter65c33762008-04-14 19:11:40 +03001199 if (unlikely(!page)) {
1200 oo = s->min;
1201 /*
1202 * Allocation may have failed due to fragmentation.
1203 * Try a lower order alloc if possible
1204 */
1205 page = alloc_slab_page(flags, node, oo);
1206 if (!page)
1207 return NULL;
Christoph Lameter81819f02007-05-06 14:49:36 -07001208
Christoph Lameter84e554e62009-12-18 16:26:23 -06001209 stat(s, ORDER_FALLBACK);
Christoph Lameter65c33762008-04-14 19:11:40 +03001210 }
Vegard Nossum5a896d92008-04-04 00:54:48 +02001211
1212 if (kmemcheck_enabled
Amerigo Wang5086c389c2009-08-19 21:44:13 +03001213 && !(s->flags & (SLAB_NOTRACK | DEBUG_DEFAULT_FLAGS))) {
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001214 int pages = 1 << oo_order(oo);
1215
1216 kmemcheck_alloc_shadow(page, oo_order(oo), flags, node);
1217
1218 /*
1219 * Objects from caches that have a constructor don't get
1220 * cleared when they're allocated, so we need to do it here.
1221 */
1222 if (s->ctor)
1223 kmemcheck_mark_uninitialized_pages(page, pages);
1224 else
1225 kmemcheck_mark_unallocated_pages(page, pages);
Vegard Nossum5a896d92008-04-04 00:54:48 +02001226 }
1227
Christoph Lameter834f3d12008-04-14 19:11:31 +03001228 page->objects = oo_objects(oo);
Christoph Lameter81819f02007-05-06 14:49:36 -07001229 mod_zone_page_state(page_zone(page),
1230 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
1231 NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
Christoph Lameter65c33762008-04-14 19:11:40 +03001232 1 << oo_order(oo));
Christoph Lameter81819f02007-05-06 14:49:36 -07001233
1234 return page;
1235}
1236
1237static void setup_object(struct kmem_cache *s, struct page *page,
1238 void *object)
1239{
Christoph Lameter3ec09742007-05-16 22:11:00 -07001240 setup_object_debug(s, page, object);
Christoph Lameter4f104932007-05-06 14:50:17 -07001241 if (unlikely(s->ctor))
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001242 s->ctor(object);
Christoph Lameter81819f02007-05-06 14:49:36 -07001243}
1244
1245static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
1246{
1247 struct page *page;
Christoph Lameter81819f02007-05-06 14:49:36 -07001248 void *start;
Christoph Lameter81819f02007-05-06 14:49:36 -07001249 void *last;
1250 void *p;
1251
Christoph Lameter6cb06222007-10-16 01:25:41 -07001252 BUG_ON(flags & GFP_SLAB_BUG_MASK);
Christoph Lameter81819f02007-05-06 14:49:36 -07001253
Christoph Lameter6cb06222007-10-16 01:25:41 -07001254 page = allocate_slab(s,
1255 flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node);
Christoph Lameter81819f02007-05-06 14:49:36 -07001256 if (!page)
1257 goto out;
1258
Christoph Lameter205ab992008-04-14 19:11:40 +03001259 inc_slabs_node(s, page_to_nid(page), page->objects);
Christoph Lameter81819f02007-05-06 14:49:36 -07001260 page->slab = s;
1261 page->flags |= 1 << PG_slab;
Christoph Lameter81819f02007-05-06 14:49:36 -07001262
1263 start = page_address(page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001264
1265 if (unlikely(s->flags & SLAB_POISON))
Christoph Lameter834f3d12008-04-14 19:11:31 +03001266 memset(start, POISON_INUSE, PAGE_SIZE << compound_order(page));
Christoph Lameter81819f02007-05-06 14:49:36 -07001267
1268 last = start;
Christoph Lameter224a88b2008-04-14 19:11:31 +03001269 for_each_object(p, s, start, page->objects) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001270 setup_object(s, page, last);
1271 set_freepointer(s, last, p);
1272 last = p;
1273 }
1274 setup_object(s, page, last);
Christoph Lametera973e9d2008-03-01 13:40:44 -08001275 set_freepointer(s, last, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -07001276
1277 page->freelist = start;
1278 page->inuse = 0;
1279out:
Christoph Lameter81819f02007-05-06 14:49:36 -07001280 return page;
1281}
1282
1283static void __free_slab(struct kmem_cache *s, struct page *page)
1284{
Christoph Lameter834f3d12008-04-14 19:11:31 +03001285 int order = compound_order(page);
1286 int pages = 1 << order;
Christoph Lameter81819f02007-05-06 14:49:36 -07001287
Christoph Lameteraf537b02010-07-09 14:07:14 -05001288 if (kmem_cache_debug(s)) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001289 void *p;
1290
1291 slab_pad_check(s, page);
Christoph Lameter224a88b2008-04-14 19:11:31 +03001292 for_each_object(p, s, page_address(page),
1293 page->objects)
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001294 check_object(s, page, p, SLUB_RED_INACTIVE);
Christoph Lameter81819f02007-05-06 14:49:36 -07001295 }
1296
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001297 kmemcheck_free_shadow(page, compound_order(page));
Vegard Nossum5a896d92008-04-04 00:54:48 +02001298
Christoph Lameter81819f02007-05-06 14:49:36 -07001299 mod_zone_page_state(page_zone(page),
1300 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
1301 NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
Pekka Enberg06428782008-01-07 23:20:27 -08001302 -pages);
Christoph Lameter81819f02007-05-06 14:49:36 -07001303
Christoph Lameter49bd5222008-04-14 18:52:18 +03001304 __ClearPageSlab(page);
1305 reset_page_mapcount(page);
Nick Piggin1eb5ac62009-05-05 19:13:44 +10001306 if (current->reclaim_state)
1307 current->reclaim_state->reclaimed_slab += pages;
Christoph Lameter834f3d12008-04-14 19:11:31 +03001308 __free_pages(page, order);
Christoph Lameter81819f02007-05-06 14:49:36 -07001309}
1310
Lai Jiangshanda9a6382011-03-10 15:22:00 +08001311#define need_reserve_slab_rcu \
1312 (sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head))
1313
Christoph Lameter81819f02007-05-06 14:49:36 -07001314static void rcu_free_slab(struct rcu_head *h)
1315{
1316 struct page *page;
1317
Lai Jiangshanda9a6382011-03-10 15:22:00 +08001318 if (need_reserve_slab_rcu)
1319 page = virt_to_head_page(h);
1320 else
1321 page = container_of((struct list_head *)h, struct page, lru);
1322
Christoph Lameter81819f02007-05-06 14:49:36 -07001323 __free_slab(page->slab, page);
1324}
1325
1326static void free_slab(struct kmem_cache *s, struct page *page)
1327{
1328 if (unlikely(s->flags & SLAB_DESTROY_BY_RCU)) {
Lai Jiangshanda9a6382011-03-10 15:22:00 +08001329 struct rcu_head *head;
1330
1331 if (need_reserve_slab_rcu) {
1332 int order = compound_order(page);
1333 int offset = (PAGE_SIZE << order) - s->reserved;
1334
1335 VM_BUG_ON(s->reserved != sizeof(*head));
1336 head = page_address(page) + offset;
1337 } else {
1338 /*
1339 * RCU free overloads the RCU head over the LRU
1340 */
1341 head = (void *)&page->lru;
1342 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001343
1344 call_rcu(head, rcu_free_slab);
1345 } else
1346 __free_slab(s, page);
1347}
1348
1349static void discard_slab(struct kmem_cache *s, struct page *page)
1350{
Christoph Lameter205ab992008-04-14 19:11:40 +03001351 dec_slabs_node(s, page_to_nid(page), page->objects);
Christoph Lameter81819f02007-05-06 14:49:36 -07001352 free_slab(s, page);
1353}
1354
1355/*
1356 * Per slab locking using the pagelock
1357 */
1358static __always_inline void slab_lock(struct page *page)
1359{
1360 bit_spin_lock(PG_locked, &page->flags);
1361}
1362
1363static __always_inline void slab_unlock(struct page *page)
1364{
Nick Piggina76d3542008-01-07 23:20:27 -08001365 __bit_spin_unlock(PG_locked, &page->flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07001366}
1367
1368static __always_inline int slab_trylock(struct page *page)
1369{
1370 int rc = 1;
1371
1372 rc = bit_spin_trylock(PG_locked, &page->flags);
1373 return rc;
1374}
1375
1376/*
1377 * Management of partially allocated slabs
1378 */
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001379static void add_partial(struct kmem_cache_node *n,
1380 struct page *page, int tail)
Christoph Lameter81819f02007-05-06 14:49:36 -07001381{
Christoph Lametere95eed52007-05-06 14:49:44 -07001382 spin_lock(&n->list_lock);
1383 n->nr_partial++;
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001384 if (tail)
1385 list_add_tail(&page->lru, &n->partial);
1386 else
1387 list_add(&page->lru, &n->partial);
Christoph Lameter81819f02007-05-06 14:49:36 -07001388 spin_unlock(&n->list_lock);
1389}
1390
Christoph Lameter62e346a2010-09-28 08:10:28 -05001391static inline void __remove_partial(struct kmem_cache_node *n,
1392 struct page *page)
1393{
1394 list_del(&page->lru);
1395 n->nr_partial--;
1396}
1397
Christoph Lameter0121c6192008-04-29 16:11:12 -07001398static void remove_partial(struct kmem_cache *s, struct page *page)
Christoph Lameter81819f02007-05-06 14:49:36 -07001399{
1400 struct kmem_cache_node *n = get_node(s, page_to_nid(page));
1401
1402 spin_lock(&n->list_lock);
Christoph Lameter62e346a2010-09-28 08:10:28 -05001403 __remove_partial(n, page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001404 spin_unlock(&n->list_lock);
1405}
1406
1407/*
Christoph Lameter672bba32007-05-09 02:32:39 -07001408 * Lock slab and remove from the partial list.
Christoph Lameter81819f02007-05-06 14:49:36 -07001409 *
Christoph Lameter672bba32007-05-09 02:32:39 -07001410 * Must hold list_lock.
Christoph Lameter81819f02007-05-06 14:49:36 -07001411 */
Christoph Lameter0121c6192008-04-29 16:11:12 -07001412static inline int lock_and_freeze_slab(struct kmem_cache_node *n,
1413 struct page *page)
Christoph Lameter81819f02007-05-06 14:49:36 -07001414{
1415 if (slab_trylock(page)) {
Christoph Lameter62e346a2010-09-28 08:10:28 -05001416 __remove_partial(n, page);
Andy Whitcroft8a380822008-07-23 21:27:18 -07001417 __SetPageSlubFrozen(page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001418 return 1;
1419 }
1420 return 0;
1421}
1422
1423/*
Christoph Lameter672bba32007-05-09 02:32:39 -07001424 * Try to allocate a partial slab from a specific node.
Christoph Lameter81819f02007-05-06 14:49:36 -07001425 */
1426static struct page *get_partial_node(struct kmem_cache_node *n)
1427{
1428 struct page *page;
1429
1430 /*
1431 * Racy check. If we mistakenly see no partial slabs then we
1432 * just allocate an empty slab. If we mistakenly try to get a
Christoph Lameter672bba32007-05-09 02:32:39 -07001433 * partial slab and there is none available then get_partials()
1434 * will return NULL.
Christoph Lameter81819f02007-05-06 14:49:36 -07001435 */
1436 if (!n || !n->nr_partial)
1437 return NULL;
1438
1439 spin_lock(&n->list_lock);
1440 list_for_each_entry(page, &n->partial, lru)
Christoph Lameter4b6f0752007-05-16 22:10:53 -07001441 if (lock_and_freeze_slab(n, page))
Christoph Lameter81819f02007-05-06 14:49:36 -07001442 goto out;
1443 page = NULL;
1444out:
1445 spin_unlock(&n->list_lock);
1446 return page;
1447}
1448
1449/*
Christoph Lameter672bba32007-05-09 02:32:39 -07001450 * Get a page from somewhere. Search in increasing NUMA distances.
Christoph Lameter81819f02007-05-06 14:49:36 -07001451 */
1452static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags)
1453{
1454#ifdef CONFIG_NUMA
1455 struct zonelist *zonelist;
Mel Gormandd1a2392008-04-28 02:12:17 -07001456 struct zoneref *z;
Mel Gorman54a6eb52008-04-28 02:12:16 -07001457 struct zone *zone;
1458 enum zone_type high_zoneidx = gfp_zone(flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07001459 struct page *page;
1460
1461 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07001462 * The defrag ratio allows a configuration of the tradeoffs between
1463 * inter node defragmentation and node local allocations. A lower
1464 * defrag_ratio increases the tendency to do local allocations
1465 * instead of attempting to obtain partial slabs from other nodes.
Christoph Lameter81819f02007-05-06 14:49:36 -07001466 *
Christoph Lameter672bba32007-05-09 02:32:39 -07001467 * If the defrag_ratio is set to 0 then kmalloc() always
1468 * returns node local objects. If the ratio is higher then kmalloc()
1469 * may return off node objects because partial slabs are obtained
1470 * from other nodes and filled up.
Christoph Lameter81819f02007-05-06 14:49:36 -07001471 *
Christoph Lameter6446faa2008-02-15 23:45:26 -08001472 * If /sys/kernel/slab/xx/defrag_ratio is set to 100 (which makes
Christoph Lameter672bba32007-05-09 02:32:39 -07001473 * defrag_ratio = 1000) then every (well almost) allocation will
1474 * first attempt to defrag slab caches on other nodes. This means
1475 * scanning over all nodes to look for partial slabs which may be
1476 * expensive if we do it every time we are trying to find a slab
1477 * with available objects.
Christoph Lameter81819f02007-05-06 14:49:36 -07001478 */
Christoph Lameter98246012008-01-07 23:20:26 -08001479 if (!s->remote_node_defrag_ratio ||
1480 get_cycles() % 1024 > s->remote_node_defrag_ratio)
Christoph Lameter81819f02007-05-06 14:49:36 -07001481 return NULL;
1482
Miao Xiec0ff7452010-05-24 14:32:08 -07001483 get_mems_allowed();
Mel Gorman0e884602008-04-28 02:12:14 -07001484 zonelist = node_zonelist(slab_node(current->mempolicy), flags);
Mel Gorman54a6eb52008-04-28 02:12:16 -07001485 for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001486 struct kmem_cache_node *n;
1487
Mel Gorman54a6eb52008-04-28 02:12:16 -07001488 n = get_node(s, zone_to_nid(zone));
Christoph Lameter81819f02007-05-06 14:49:36 -07001489
Mel Gorman54a6eb52008-04-28 02:12:16 -07001490 if (n && cpuset_zone_allowed_hardwall(zone, flags) &&
David Rientjes3b89d7d2009-02-22 17:40:07 -08001491 n->nr_partial > s->min_partial) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001492 page = get_partial_node(n);
Miao Xiec0ff7452010-05-24 14:32:08 -07001493 if (page) {
1494 put_mems_allowed();
Christoph Lameter81819f02007-05-06 14:49:36 -07001495 return page;
Miao Xiec0ff7452010-05-24 14:32:08 -07001496 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001497 }
1498 }
Miao Xiec0ff7452010-05-24 14:32:08 -07001499 put_mems_allowed();
Christoph Lameter81819f02007-05-06 14:49:36 -07001500#endif
1501 return NULL;
1502}
1503
1504/*
1505 * Get a partial page, lock it and return it.
1506 */
1507static struct page *get_partial(struct kmem_cache *s, gfp_t flags, int node)
1508{
1509 struct page *page;
Christoph Lameter2154a332010-07-09 14:07:10 -05001510 int searchnode = (node == NUMA_NO_NODE) ? numa_node_id() : node;
Christoph Lameter81819f02007-05-06 14:49:36 -07001511
1512 page = get_partial_node(get_node(s, searchnode));
Christoph Lameter33de04e2011-04-15 14:48:12 -05001513 if (page || node != NUMA_NO_NODE)
Christoph Lameter81819f02007-05-06 14:49:36 -07001514 return page;
1515
1516 return get_any_partial(s, flags);
1517}
1518
1519/*
1520 * Move a page back to the lists.
1521 *
1522 * Must be called with the slab lock held.
1523 *
1524 * On exit the slab lock will have been dropped.
1525 */
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001526static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail)
Namhyung Kim34789732010-09-29 21:02:14 +09001527 __releases(bitlock)
Christoph Lameter81819f02007-05-06 14:49:36 -07001528{
Christoph Lametere95eed52007-05-06 14:49:44 -07001529 struct kmem_cache_node *n = get_node(s, page_to_nid(page));
1530
Andy Whitcroft8a380822008-07-23 21:27:18 -07001531 __ClearPageSlubFrozen(page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001532 if (page->inuse) {
Christoph Lametere95eed52007-05-06 14:49:44 -07001533
Christoph Lametera973e9d2008-03-01 13:40:44 -08001534 if (page->freelist) {
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001535 add_partial(n, page, tail);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001536 stat(s, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08001537 } else {
Christoph Lameter84e554e62009-12-18 16:26:23 -06001538 stat(s, DEACTIVATE_FULL);
Christoph Lameteraf537b02010-07-09 14:07:14 -05001539 if (kmem_cache_debug(s) && (s->flags & SLAB_STORE_USER))
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08001540 add_full(n, page);
1541 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001542 slab_unlock(page);
1543 } else {
Christoph Lameter84e554e62009-12-18 16:26:23 -06001544 stat(s, DEACTIVATE_EMPTY);
David Rientjes3b89d7d2009-02-22 17:40:07 -08001545 if (n->nr_partial < s->min_partial) {
Christoph Lametere95eed52007-05-06 14:49:44 -07001546 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07001547 * Adding an empty slab to the partial slabs in order
1548 * to avoid page allocator overhead. This slab needs
1549 * to come after the other slabs with objects in
Christoph Lameter6446faa2008-02-15 23:45:26 -08001550 * so that the others get filled first. That way the
1551 * size of the partial list stays small.
1552 *
Christoph Lameter0121c6192008-04-29 16:11:12 -07001553 * kmem_cache_shrink can reclaim any empty slabs from
1554 * the partial list.
Christoph Lametere95eed52007-05-06 14:49:44 -07001555 */
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001556 add_partial(n, page, 1);
Christoph Lametere95eed52007-05-06 14:49:44 -07001557 slab_unlock(page);
1558 } else {
1559 slab_unlock(page);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001560 stat(s, FREE_SLAB);
Christoph Lametere95eed52007-05-06 14:49:44 -07001561 discard_slab(s, page);
1562 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001563 }
1564}
1565
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001566#ifdef CONFIG_PREEMPT
1567/*
1568 * Calculate the next globally unique transaction for disambiguiation
1569 * during cmpxchg. The transactions start with the cpu number and are then
1570 * incremented by CONFIG_NR_CPUS.
1571 */
1572#define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS)
1573#else
1574/*
1575 * No preemption supported therefore also no need to check for
1576 * different cpus.
1577 */
1578#define TID_STEP 1
1579#endif
1580
1581static inline unsigned long next_tid(unsigned long tid)
1582{
1583 return tid + TID_STEP;
1584}
1585
1586static inline unsigned int tid_to_cpu(unsigned long tid)
1587{
1588 return tid % TID_STEP;
1589}
1590
1591static inline unsigned long tid_to_event(unsigned long tid)
1592{
1593 return tid / TID_STEP;
1594}
1595
1596static inline unsigned int init_tid(int cpu)
1597{
1598 return cpu;
1599}
1600
1601static inline void note_cmpxchg_failure(const char *n,
1602 const struct kmem_cache *s, unsigned long tid)
1603{
1604#ifdef SLUB_DEBUG_CMPXCHG
1605 unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid);
1606
1607 printk(KERN_INFO "%s %s: cmpxchg redo ", n, s->name);
1608
1609#ifdef CONFIG_PREEMPT
1610 if (tid_to_cpu(tid) != tid_to_cpu(actual_tid))
1611 printk("due to cpu change %d -> %d\n",
1612 tid_to_cpu(tid), tid_to_cpu(actual_tid));
1613 else
1614#endif
1615 if (tid_to_event(tid) != tid_to_event(actual_tid))
1616 printk("due to cpu running other code. Event %ld->%ld\n",
1617 tid_to_event(tid), tid_to_event(actual_tid));
1618 else
1619 printk("for unknown reason: actual=%lx was=%lx target=%lx\n",
1620 actual_tid, tid, next_tid(tid));
1621#endif
Christoph Lameter4fdccdf2011-03-22 13:35:00 -05001622 stat(s, CMPXCHG_DOUBLE_CPU_FAIL);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001623}
1624
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001625void init_kmem_cache_cpus(struct kmem_cache *s)
1626{
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001627 int cpu;
1628
1629 for_each_possible_cpu(cpu)
1630 per_cpu_ptr(s->cpu_slab, cpu)->tid = init_tid(cpu);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001631}
Christoph Lameter81819f02007-05-06 14:49:36 -07001632/*
1633 * Remove the cpu slab
1634 */
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001635static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
Namhyung Kim34789732010-09-29 21:02:14 +09001636 __releases(bitlock)
Christoph Lameter81819f02007-05-06 14:49:36 -07001637{
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001638 struct page *page = c->page;
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001639 int tail = 1;
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08001640
Christoph Lameterb773ad72008-03-04 11:10:17 -08001641 if (page->freelist)
Christoph Lameter84e554e62009-12-18 16:26:23 -06001642 stat(s, DEACTIVATE_REMOTE_FREES);
Christoph Lameter894b8782007-05-10 03:15:16 -07001643 /*
Christoph Lameter6446faa2008-02-15 23:45:26 -08001644 * Merge cpu freelist into slab freelist. Typically we get here
Christoph Lameter894b8782007-05-10 03:15:16 -07001645 * because both freelists are empty. So this is unlikely
1646 * to occur.
1647 */
Christoph Lametera973e9d2008-03-01 13:40:44 -08001648 while (unlikely(c->freelist)) {
Christoph Lameter894b8782007-05-10 03:15:16 -07001649 void **object;
1650
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001651 tail = 0; /* Hot objects. Put the slab first */
1652
Christoph Lameter894b8782007-05-10 03:15:16 -07001653 /* Retrieve object from cpu_freelist */
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001654 object = c->freelist;
Christoph Lameterff120592009-12-18 16:26:22 -06001655 c->freelist = get_freepointer(s, c->freelist);
Christoph Lameter894b8782007-05-10 03:15:16 -07001656
1657 /* And put onto the regular freelist */
Christoph Lameterff120592009-12-18 16:26:22 -06001658 set_freepointer(s, object, page->freelist);
Christoph Lameter894b8782007-05-10 03:15:16 -07001659 page->freelist = object;
1660 page->inuse--;
1661 }
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001662 c->page = NULL;
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001663 c->tid = next_tid(c->tid);
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001664 unfreeze_slab(s, page, tail);
Christoph Lameter81819f02007-05-06 14:49:36 -07001665}
1666
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001667static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07001668{
Christoph Lameter84e554e62009-12-18 16:26:23 -06001669 stat(s, CPUSLAB_FLUSH);
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001670 slab_lock(c->page);
1671 deactivate_slab(s, c);
Christoph Lameter81819f02007-05-06 14:49:36 -07001672}
1673
1674/*
1675 * Flush cpu slab.
Christoph Lameter6446faa2008-02-15 23:45:26 -08001676 *
Christoph Lameter81819f02007-05-06 14:49:36 -07001677 * Called from IPI handler with interrupts disabled.
1678 */
Christoph Lameter0c710012007-07-17 04:03:24 -07001679static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu)
Christoph Lameter81819f02007-05-06 14:49:36 -07001680{
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06001681 struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
Christoph Lameter81819f02007-05-06 14:49:36 -07001682
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001683 if (likely(c && c->page))
1684 flush_slab(s, c);
Christoph Lameter81819f02007-05-06 14:49:36 -07001685}
1686
1687static void flush_cpu_slab(void *d)
1688{
1689 struct kmem_cache *s = d;
Christoph Lameter81819f02007-05-06 14:49:36 -07001690
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001691 __flush_cpu_slab(s, smp_processor_id());
Christoph Lameter81819f02007-05-06 14:49:36 -07001692}
1693
1694static void flush_all(struct kmem_cache *s)
1695{
Jens Axboe15c8b6c2008-05-09 09:39:44 +02001696 on_each_cpu(flush_cpu_slab, s, 1);
Christoph Lameter81819f02007-05-06 14:49:36 -07001697}
1698
1699/*
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001700 * Check if the objects in a per cpu structure fit numa
1701 * locality expectations.
1702 */
1703static inline int node_match(struct kmem_cache_cpu *c, int node)
1704{
1705#ifdef CONFIG_NUMA
Christoph Lameter2154a332010-07-09 14:07:10 -05001706 if (node != NUMA_NO_NODE && c->node != node)
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001707 return 0;
1708#endif
1709 return 1;
1710}
1711
Pekka Enberg781b2ba2009-06-10 18:50:32 +03001712static int count_free(struct page *page)
1713{
1714 return page->objects - page->inuse;
1715}
1716
1717static unsigned long count_partial(struct kmem_cache_node *n,
1718 int (*get_count)(struct page *))
1719{
1720 unsigned long flags;
1721 unsigned long x = 0;
1722 struct page *page;
1723
1724 spin_lock_irqsave(&n->list_lock, flags);
1725 list_for_each_entry(page, &n->partial, lru)
1726 x += get_count(page);
1727 spin_unlock_irqrestore(&n->list_lock, flags);
1728 return x;
1729}
1730
Alexander Beregalov26c02cf2009-06-11 14:08:48 +04001731static inline unsigned long node_nr_objs(struct kmem_cache_node *n)
1732{
1733#ifdef CONFIG_SLUB_DEBUG
1734 return atomic_long_read(&n->total_objects);
1735#else
1736 return 0;
1737#endif
1738}
1739
Pekka Enberg781b2ba2009-06-10 18:50:32 +03001740static noinline void
1741slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid)
1742{
1743 int node;
1744
1745 printk(KERN_WARNING
1746 "SLUB: Unable to allocate memory on node %d (gfp=0x%x)\n",
1747 nid, gfpflags);
1748 printk(KERN_WARNING " cache: %s, object size: %d, buffer size: %d, "
1749 "default order: %d, min order: %d\n", s->name, s->objsize,
1750 s->size, oo_order(s->oo), oo_order(s->min));
1751
David Rientjesfa5ec8a2009-07-07 00:14:14 -07001752 if (oo_order(s->min) > get_order(s->objsize))
1753 printk(KERN_WARNING " %s debugging increased min order, use "
1754 "slub_debug=O to disable.\n", s->name);
1755
Pekka Enberg781b2ba2009-06-10 18:50:32 +03001756 for_each_online_node(node) {
1757 struct kmem_cache_node *n = get_node(s, node);
1758 unsigned long nr_slabs;
1759 unsigned long nr_objs;
1760 unsigned long nr_free;
1761
1762 if (!n)
1763 continue;
1764
Alexander Beregalov26c02cf2009-06-11 14:08:48 +04001765 nr_free = count_partial(n, count_free);
1766 nr_slabs = node_nr_slabs(n);
1767 nr_objs = node_nr_objs(n);
Pekka Enberg781b2ba2009-06-10 18:50:32 +03001768
1769 printk(KERN_WARNING
1770 " node %d: slabs: %ld, objs: %ld, free: %ld\n",
1771 node, nr_slabs, nr_objs, nr_free);
1772 }
1773}
1774
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001775/*
Christoph Lameter894b8782007-05-10 03:15:16 -07001776 * Slow path. The lockless freelist is empty or we need to perform
1777 * debugging duties.
Christoph Lameter81819f02007-05-06 14:49:36 -07001778 *
Christoph Lameter894b8782007-05-10 03:15:16 -07001779 * Interrupts are disabled.
Christoph Lameter81819f02007-05-06 14:49:36 -07001780 *
Christoph Lameter894b8782007-05-10 03:15:16 -07001781 * Processing is still very fast if new objects have been freed to the
1782 * regular freelist. In that case we simply take over the regular freelist
1783 * as the lockless freelist and zap the regular freelist.
Christoph Lameter81819f02007-05-06 14:49:36 -07001784 *
Christoph Lameter894b8782007-05-10 03:15:16 -07001785 * If that is not working then we fall back to the partial lists. We take the
1786 * first element of the freelist as the object to allocate now and move the
1787 * rest of the freelist to the lockless freelist.
1788 *
1789 * And if we were unable to get a new slab from the partial slab lists then
Christoph Lameter6446faa2008-02-15 23:45:26 -08001790 * we need to allocate a new slab. This is the slowest path since it involves
1791 * a call to the page allocator and the setup of a new slab.
Christoph Lameter81819f02007-05-06 14:49:36 -07001792 */
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001793static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
1794 unsigned long addr, struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07001795{
Christoph Lameter81819f02007-05-06 14:49:36 -07001796 void **object;
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001797 struct page *page;
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001798 unsigned long flags;
1799
1800 local_irq_save(flags);
1801#ifdef CONFIG_PREEMPT
1802 /*
1803 * We may have been preempted and rescheduled on a different
1804 * cpu before disabling interrupts. Need to reload cpu area
1805 * pointer.
1806 */
1807 c = this_cpu_ptr(s->cpu_slab);
1808#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07001809
Linus Torvaldse72e9c22008-03-27 20:56:33 -07001810 /* We handle __GFP_ZERO in the caller */
1811 gfpflags &= ~__GFP_ZERO;
1812
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001813 page = c->page;
1814 if (!page)
Christoph Lameter81819f02007-05-06 14:49:36 -07001815 goto new_slab;
1816
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001817 slab_lock(page);
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001818 if (unlikely(!node_match(c, node)))
Christoph Lameter81819f02007-05-06 14:49:36 -07001819 goto another_slab;
Christoph Lameter6446faa2008-02-15 23:45:26 -08001820
Christoph Lameter84e554e62009-12-18 16:26:23 -06001821 stat(s, ALLOC_REFILL);
Christoph Lameter6446faa2008-02-15 23:45:26 -08001822
Christoph Lameter894b8782007-05-10 03:15:16 -07001823load_freelist:
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001824 object = page->freelist;
Christoph Lametera973e9d2008-03-01 13:40:44 -08001825 if (unlikely(!object))
Christoph Lameter81819f02007-05-06 14:49:36 -07001826 goto another_slab;
Christoph Lameteraf537b02010-07-09 14:07:14 -05001827 if (kmem_cache_debug(s))
Christoph Lameter81819f02007-05-06 14:49:36 -07001828 goto debug;
1829
Christoph Lameterff120592009-12-18 16:26:22 -06001830 c->freelist = get_freepointer(s, object);
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001831 page->inuse = page->objects;
1832 page->freelist = NULL;
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001833
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001834 slab_unlock(page);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001835 c->tid = next_tid(c->tid);
1836 local_irq_restore(flags);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001837 stat(s, ALLOC_SLOWPATH);
Christoph Lameter81819f02007-05-06 14:49:36 -07001838 return object;
1839
1840another_slab:
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001841 deactivate_slab(s, c);
Christoph Lameter81819f02007-05-06 14:49:36 -07001842
1843new_slab:
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001844 page = get_partial(s, gfpflags, node);
1845 if (page) {
Christoph Lameter84e554e62009-12-18 16:26:23 -06001846 stat(s, ALLOC_FROM_PARTIAL);
Christoph Lameterdc1fb7f2011-04-15 14:48:15 -05001847 c->node = page_to_nid(page);
1848 c->page = page;
Christoph Lameter894b8782007-05-10 03:15:16 -07001849 goto load_freelist;
Christoph Lameter81819f02007-05-06 14:49:36 -07001850 }
1851
Christoph Lameterc1d50832010-08-20 12:37:17 -05001852 gfpflags &= gfp_allowed_mask;
Christoph Lameterb811c202007-10-16 23:25:51 -07001853 if (gfpflags & __GFP_WAIT)
1854 local_irq_enable();
1855
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001856 page = new_slab(s, gfpflags, node);
Christoph Lameterb811c202007-10-16 23:25:51 -07001857
1858 if (gfpflags & __GFP_WAIT)
1859 local_irq_disable();
1860
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001861 if (page) {
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06001862 c = __this_cpu_ptr(s->cpu_slab);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001863 stat(s, ALLOC_SLAB);
Christoph Lameter05aa3452007-11-05 11:31:58 -08001864 if (c->page)
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001865 flush_slab(s, c);
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001866
1867 slab_lock(page);
1868 __SetPageSlubFrozen(page);
David Rientjesbd07d872011-05-12 13:10:49 -07001869 c->node = page_to_nid(page);
1870 c->page = page;
Christoph Lameter4b6f0752007-05-16 22:10:53 -07001871 goto load_freelist;
Christoph Lameter81819f02007-05-06 14:49:36 -07001872 }
Pekka Enberg95f85982009-06-11 16:18:09 +03001873 if (!(gfpflags & __GFP_NOWARN) && printk_ratelimit())
1874 slab_out_of_memory(s, gfpflags, node);
Christoph Lameter2fd66c52011-03-22 13:32:53 -05001875 local_irq_restore(flags);
Christoph Lameter71c7a062008-02-14 14:28:01 -08001876 return NULL;
Christoph Lameter81819f02007-05-06 14:49:36 -07001877debug:
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001878 if (!alloc_debug_processing(s, page, object, addr))
Christoph Lameter81819f02007-05-06 14:49:36 -07001879 goto another_slab;
Christoph Lameter894b8782007-05-10 03:15:16 -07001880
Christoph Lameter01ad8a72011-04-15 14:48:14 -05001881 page->inuse++;
1882 page->freelist = get_freepointer(s, object);
Christoph Lameter442b06b2011-05-17 16:29:31 -05001883 deactivate_slab(s, c);
1884 c->page = NULL;
Pekka Enberg15b7c512010-10-02 11:32:32 +03001885 c->node = NUMA_NO_NODE;
Christoph Lametera71ae472011-05-25 09:47:43 -05001886 local_irq_restore(flags);
1887 return object;
Christoph Lameter894b8782007-05-10 03:15:16 -07001888}
1889
1890/*
1891 * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc)
1892 * have the fastpath folded into their functions. So no function call
1893 * overhead for requests that can be satisfied on the fastpath.
1894 *
1895 * The fastpath works by first checking if the lockless freelist can be used.
1896 * If not then __slab_alloc is called for slow processing.
1897 *
1898 * Otherwise we can simply pick the next object from the lockless free list.
1899 */
Pekka Enberg06428782008-01-07 23:20:27 -08001900static __always_inline void *slab_alloc(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001901 gfp_t gfpflags, int node, unsigned long addr)
Christoph Lameter894b8782007-05-10 03:15:16 -07001902{
Christoph Lameter894b8782007-05-10 03:15:16 -07001903 void **object;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001904 struct kmem_cache_cpu *c;
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001905 unsigned long tid;
Christoph Lameter1f842602008-01-07 23:20:30 -08001906
Christoph Lameterc016b0b2010-08-20 12:37:16 -05001907 if (slab_pre_alloc_hook(s, gfpflags))
Akinobu Mita773ff602008-12-23 19:37:01 +09001908 return NULL;
1909
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001910redo:
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001911
1912 /*
1913 * Must read kmem_cache cpu data via this cpu ptr. Preemption is
1914 * enabled. We may switch back and forth between cpus while
1915 * reading from one cpu area. That does not matter as long
1916 * as we end up on the original cpu again when doing the cmpxchg.
1917 */
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06001918 c = __this_cpu_ptr(s->cpu_slab);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001919
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001920 /*
1921 * The transaction ids are globally unique per cpu and per operation on
1922 * a per cpu queue. Thus they can be guarantee that the cmpxchg_double
1923 * occurs on the right processor and that there was no operation on the
1924 * linked list in between.
1925 */
1926 tid = c->tid;
1927 barrier();
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001928
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06001929 object = c->freelist;
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06001930 if (unlikely(!object || !node_match(c, node)))
Christoph Lameter894b8782007-05-10 03:15:16 -07001931
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001932 object = __slab_alloc(s, gfpflags, node, addr, c);
Christoph Lameter894b8782007-05-10 03:15:16 -07001933
1934 else {
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001935 /*
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001936 * The cmpxchg will only match if there was no additional
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001937 * operation and if we are on the right processor.
1938 *
1939 * The cmpxchg does the following atomically (without lock semantics!)
1940 * 1. Relocate first pointer to the current per cpu area.
1941 * 2. Verify that tid and freelist have not been changed
1942 * 3. If they were not changed replace tid and freelist
1943 *
1944 * Since this is without lock semantics the protection is only against
1945 * code executing on this cpu *not* from access by other cpus.
1946 */
Thomas Gleixner30106b82011-05-04 15:38:19 +02001947 if (unlikely(!irqsafe_cpu_cmpxchg_double(
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001948 s->cpu_slab->freelist, s->cpu_slab->tid,
1949 object, tid,
Christoph Lameter1393d9a2011-05-16 15:26:08 -05001950 get_freepointer_safe(s, object), next_tid(tid)))) {
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001951
1952 note_cmpxchg_failure("slab_alloc", s, tid);
1953 goto redo;
1954 }
Christoph Lameter84e554e62009-12-18 16:26:23 -06001955 stat(s, ALLOC_FASTPATH);
Christoph Lameter894b8782007-05-10 03:15:16 -07001956 }
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001957
Pekka Enberg74e21342009-11-25 20:14:48 +02001958 if (unlikely(gfpflags & __GFP_ZERO) && object)
Christoph Lameterff120592009-12-18 16:26:22 -06001959 memset(object, 0, s->objsize);
Christoph Lameterd07dbea2007-07-17 04:03:23 -07001960
Christoph Lameterc016b0b2010-08-20 12:37:16 -05001961 slab_post_alloc_hook(s, gfpflags, object);
Vegard Nossum5a896d92008-04-04 00:54:48 +02001962
Christoph Lameter894b8782007-05-10 03:15:16 -07001963 return object;
Christoph Lameter81819f02007-05-06 14:49:36 -07001964}
1965
1966void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags)
1967{
Christoph Lameter2154a332010-07-09 14:07:10 -05001968 void *ret = slab_alloc(s, gfpflags, NUMA_NO_NODE, _RET_IP_);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001969
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02001970 trace_kmem_cache_alloc(_RET_IP_, ret, s->objsize, s->size, gfpflags);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001971
1972 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07001973}
1974EXPORT_SYMBOL(kmem_cache_alloc);
1975
Li Zefan0f24f122009-12-11 15:45:30 +08001976#ifdef CONFIG_TRACING
Richard Kennedy4a923792010-10-21 10:29:19 +01001977void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size)
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001978{
Richard Kennedy4a923792010-10-21 10:29:19 +01001979 void *ret = slab_alloc(s, gfpflags, NUMA_NO_NODE, _RET_IP_);
1980 trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags);
1981 return ret;
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001982}
Richard Kennedy4a923792010-10-21 10:29:19 +01001983EXPORT_SYMBOL(kmem_cache_alloc_trace);
1984
1985void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
1986{
1987 void *ret = kmalloc_order(size, flags, order);
1988 trace_kmalloc(_RET_IP_, ret, size, PAGE_SIZE << order, flags);
1989 return ret;
1990}
1991EXPORT_SYMBOL(kmalloc_order_trace);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001992#endif
1993
Christoph Lameter81819f02007-05-06 14:49:36 -07001994#ifdef CONFIG_NUMA
1995void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node)
1996{
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001997 void *ret = slab_alloc(s, gfpflags, node, _RET_IP_);
1998
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02001999 trace_kmem_cache_alloc_node(_RET_IP_, ret,
2000 s->objsize, s->size, gfpflags, node);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002001
2002 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002003}
2004EXPORT_SYMBOL(kmem_cache_alloc_node);
Christoph Lameter81819f02007-05-06 14:49:36 -07002005
Li Zefan0f24f122009-12-11 15:45:30 +08002006#ifdef CONFIG_TRACING
Richard Kennedy4a923792010-10-21 10:29:19 +01002007void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002008 gfp_t gfpflags,
Richard Kennedy4a923792010-10-21 10:29:19 +01002009 int node, size_t size)
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002010{
Richard Kennedy4a923792010-10-21 10:29:19 +01002011 void *ret = slab_alloc(s, gfpflags, node, _RET_IP_);
2012
2013 trace_kmalloc_node(_RET_IP_, ret,
2014 size, s->size, gfpflags, node);
2015 return ret;
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002016}
Richard Kennedy4a923792010-10-21 10:29:19 +01002017EXPORT_SYMBOL(kmem_cache_alloc_node_trace);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002018#endif
Namhyung Kim5d1f57e2010-09-29 21:02:15 +09002019#endif
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002020
Christoph Lameter81819f02007-05-06 14:49:36 -07002021/*
Christoph Lameter894b8782007-05-10 03:15:16 -07002022 * Slow patch handling. This may still be called frequently since objects
2023 * have a longer lifetime than the cpu slabs in most processing loads.
Christoph Lameter81819f02007-05-06 14:49:36 -07002024 *
Christoph Lameter894b8782007-05-10 03:15:16 -07002025 * So we still attempt to reduce cache line usage. Just take the slab
2026 * lock and free the item. If there is no additional partial page
2027 * handling required then we can return immediately.
Christoph Lameter81819f02007-05-06 14:49:36 -07002028 */
Christoph Lameter894b8782007-05-10 03:15:16 -07002029static void __slab_free(struct kmem_cache *s, struct page *page,
Christoph Lameterff120592009-12-18 16:26:22 -06002030 void *x, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -07002031{
2032 void *prior;
2033 void **object = (void *)x;
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002034 unsigned long flags;
Christoph Lameter81819f02007-05-06 14:49:36 -07002035
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002036 local_irq_save(flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07002037 slab_lock(page);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002038 stat(s, FREE_SLOWPATH);
Christoph Lameter81819f02007-05-06 14:49:36 -07002039
Christoph Lameter8dc16c62011-04-15 14:48:16 -05002040 if (kmem_cache_debug(s) && !free_debug_processing(s, page, x, addr))
2041 goto out_unlock;
Christoph Lameter6446faa2008-02-15 23:45:26 -08002042
Christoph Lameterff120592009-12-18 16:26:22 -06002043 prior = page->freelist;
2044 set_freepointer(s, object, prior);
Christoph Lameter81819f02007-05-06 14:49:36 -07002045 page->freelist = object;
2046 page->inuse--;
2047
Andy Whitcroft8a380822008-07-23 21:27:18 -07002048 if (unlikely(PageSlubFrozen(page))) {
Christoph Lameter84e554e62009-12-18 16:26:23 -06002049 stat(s, FREE_FROZEN);
Christoph Lameter81819f02007-05-06 14:49:36 -07002050 goto out_unlock;
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08002051 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002052
2053 if (unlikely(!page->inuse))
2054 goto slab_empty;
2055
2056 /*
Christoph Lameter6446faa2008-02-15 23:45:26 -08002057 * Objects left in the slab. If it was not on the partial list before
Christoph Lameter81819f02007-05-06 14:49:36 -07002058 * then add it.
2059 */
Christoph Lametera973e9d2008-03-01 13:40:44 -08002060 if (unlikely(!prior)) {
Christoph Lameter7c2e1322008-01-07 23:20:27 -08002061 add_partial(get_node(s, page_to_nid(page)), page, 1);
Christoph Lameter84e554e62009-12-18 16:26:23 -06002062 stat(s, FREE_ADD_PARTIAL);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08002063 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002064
2065out_unlock:
2066 slab_unlock(page);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002067 local_irq_restore(flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07002068 return;
2069
2070slab_empty:
Christoph Lametera973e9d2008-03-01 13:40:44 -08002071 if (prior) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002072 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07002073 * Slab still on the partial list.
Christoph Lameter81819f02007-05-06 14:49:36 -07002074 */
2075 remove_partial(s, page);
Christoph Lameter84e554e62009-12-18 16:26:23 -06002076 stat(s, FREE_REMOVE_PARTIAL);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08002077 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002078 slab_unlock(page);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002079 local_irq_restore(flags);
Christoph Lameter84e554e62009-12-18 16:26:23 -06002080 stat(s, FREE_SLAB);
Christoph Lameter81819f02007-05-06 14:49:36 -07002081 discard_slab(s, page);
Christoph Lameter81819f02007-05-06 14:49:36 -07002082}
2083
Christoph Lameter894b8782007-05-10 03:15:16 -07002084/*
2085 * Fastpath with forced inlining to produce a kfree and kmem_cache_free that
2086 * can perform fastpath freeing without additional function calls.
2087 *
2088 * The fastpath is only possible if we are freeing to the current cpu slab
2089 * of this processor. This typically the case if we have just allocated
2090 * the item before.
2091 *
2092 * If fastpath is not possible then fall back to __slab_free where we deal
2093 * with all sorts of special processing.
2094 */
Pekka Enberg06428782008-01-07 23:20:27 -08002095static __always_inline void slab_free(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03002096 struct page *page, void *x, unsigned long addr)
Christoph Lameter894b8782007-05-10 03:15:16 -07002097{
2098 void **object = (void *)x;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002099 struct kmem_cache_cpu *c;
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002100 unsigned long tid;
Christoph Lameter1f842602008-01-07 23:20:30 -08002101
Christoph Lameterc016b0b2010-08-20 12:37:16 -05002102 slab_free_hook(s, x);
2103
Christoph Lametera24c5a02011-03-15 12:45:21 -05002104redo:
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002105
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002106 /*
2107 * Determine the currently cpus per cpu slab.
2108 * The cpu may change afterward. However that does not matter since
2109 * data is retrieved via this pointer. If we are on the same cpu
2110 * during the cmpxchg then the free will succedd.
2111 */
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002112 c = __this_cpu_ptr(s->cpu_slab);
Christoph Lameterc016b0b2010-08-20 12:37:16 -05002113
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002114 tid = c->tid;
2115 barrier();
Christoph Lameterc016b0b2010-08-20 12:37:16 -05002116
Christoph Lameter442b06b2011-05-17 16:29:31 -05002117 if (likely(page == c->page)) {
Christoph Lameterff120592009-12-18 16:26:22 -06002118 set_freepointer(s, object, c->freelist);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002119
Thomas Gleixner30106b82011-05-04 15:38:19 +02002120 if (unlikely(!irqsafe_cpu_cmpxchg_double(
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002121 s->cpu_slab->freelist, s->cpu_slab->tid,
2122 c->freelist, tid,
2123 object, next_tid(tid)))) {
2124
2125 note_cmpxchg_failure("slab_free", s, tid);
2126 goto redo;
2127 }
Christoph Lameter84e554e62009-12-18 16:26:23 -06002128 stat(s, FREE_FASTPATH);
Christoph Lameter894b8782007-05-10 03:15:16 -07002129 } else
Christoph Lameterff120592009-12-18 16:26:22 -06002130 __slab_free(s, page, x, addr);
Christoph Lameter894b8782007-05-10 03:15:16 -07002131
Christoph Lameter894b8782007-05-10 03:15:16 -07002132}
2133
Christoph Lameter81819f02007-05-06 14:49:36 -07002134void kmem_cache_free(struct kmem_cache *s, void *x)
2135{
Christoph Lameter77c5e2d2007-05-06 14:49:42 -07002136 struct page *page;
Christoph Lameter81819f02007-05-06 14:49:36 -07002137
Christoph Lameterb49af682007-05-06 14:49:41 -07002138 page = virt_to_head_page(x);
Christoph Lameter81819f02007-05-06 14:49:36 -07002139
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03002140 slab_free(s, page, x, _RET_IP_);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002141
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02002142 trace_kmem_cache_free(_RET_IP_, x);
Christoph Lameter81819f02007-05-06 14:49:36 -07002143}
2144EXPORT_SYMBOL(kmem_cache_free);
2145
Christoph Lameter81819f02007-05-06 14:49:36 -07002146/*
Christoph Lameter672bba32007-05-09 02:32:39 -07002147 * Object placement in a slab is made very easy because we always start at
2148 * offset 0. If we tune the size of the object to the alignment then we can
2149 * get the required alignment by putting one properly sized object after
2150 * another.
Christoph Lameter81819f02007-05-06 14:49:36 -07002151 *
2152 * Notice that the allocation order determines the sizes of the per cpu
2153 * caches. Each processor has always one slab available for allocations.
2154 * Increasing the allocation order reduces the number of times that slabs
Christoph Lameter672bba32007-05-09 02:32:39 -07002155 * must be moved on and off the partial lists and is therefore a factor in
Christoph Lameter81819f02007-05-06 14:49:36 -07002156 * locking overhead.
Christoph Lameter81819f02007-05-06 14:49:36 -07002157 */
2158
2159/*
2160 * Mininum / Maximum order of slab pages. This influences locking overhead
2161 * and slab fragmentation. A higher order reduces the number of partial slabs
2162 * and increases the number of allocations possible without having to
2163 * take the list_lock.
2164 */
2165static int slub_min_order;
Christoph Lameter114e9e82008-04-14 19:11:41 +03002166static int slub_max_order = PAGE_ALLOC_COSTLY_ORDER;
Christoph Lameter9b2cd502008-04-14 19:11:41 +03002167static int slub_min_objects;
Christoph Lameter81819f02007-05-06 14:49:36 -07002168
2169/*
2170 * Merge control. If this is set then no merging of slab caches will occur.
Christoph Lameter672bba32007-05-09 02:32:39 -07002171 * (Could be removed. This was introduced to pacify the merge skeptics.)
Christoph Lameter81819f02007-05-06 14:49:36 -07002172 */
2173static int slub_nomerge;
2174
2175/*
Christoph Lameter81819f02007-05-06 14:49:36 -07002176 * Calculate the order of allocation given an slab object size.
2177 *
Christoph Lameter672bba32007-05-09 02:32:39 -07002178 * The order of allocation has significant impact on performance and other
2179 * system components. Generally order 0 allocations should be preferred since
2180 * order 0 does not cause fragmentation in the page allocator. Larger objects
2181 * be problematic to put into order 0 slabs because there may be too much
Christoph Lameterc124f5b2008-04-14 19:13:29 +03002182 * unused space left. We go to a higher order if more than 1/16th of the slab
Christoph Lameter672bba32007-05-09 02:32:39 -07002183 * would be wasted.
Christoph Lameter81819f02007-05-06 14:49:36 -07002184 *
Christoph Lameter672bba32007-05-09 02:32:39 -07002185 * In order to reach satisfactory performance we must ensure that a minimum
2186 * number of objects is in one slab. Otherwise we may generate too much
2187 * activity on the partial lists which requires taking the list_lock. This is
2188 * less a concern for large slabs though which are rarely used.
Christoph Lameter81819f02007-05-06 14:49:36 -07002189 *
Christoph Lameter672bba32007-05-09 02:32:39 -07002190 * slub_max_order specifies the order where we begin to stop considering the
2191 * number of objects in a slab as critical. If we reach slub_max_order then
2192 * we try to keep the page order as low as possible. So we accept more waste
2193 * of space in favor of a small page order.
2194 *
2195 * Higher order allocations also allow the placement of more objects in a
2196 * slab and thereby reduce object handling overhead. If the user has
2197 * requested a higher mininum order then we start with that one instead of
2198 * the smallest order which will fit the object.
Christoph Lameter81819f02007-05-06 14:49:36 -07002199 */
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002200static inline int slab_order(int size, int min_objects,
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002201 int max_order, int fract_leftover, int reserved)
Christoph Lameter81819f02007-05-06 14:49:36 -07002202{
2203 int order;
2204 int rem;
Christoph Lameter6300ea72007-07-17 04:03:20 -07002205 int min_order = slub_min_order;
Christoph Lameter81819f02007-05-06 14:49:36 -07002206
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002207 if (order_objects(min_order, size, reserved) > MAX_OBJS_PER_PAGE)
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +04002208 return get_order(size * MAX_OBJS_PER_PAGE) - 1;
Christoph Lameter39b26462008-04-14 19:11:30 +03002209
Christoph Lameter6300ea72007-07-17 04:03:20 -07002210 for (order = max(min_order,
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002211 fls(min_objects * size - 1) - PAGE_SHIFT);
2212 order <= max_order; order++) {
2213
Christoph Lameter81819f02007-05-06 14:49:36 -07002214 unsigned long slab_size = PAGE_SIZE << order;
2215
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002216 if (slab_size < min_objects * size + reserved)
Christoph Lameter81819f02007-05-06 14:49:36 -07002217 continue;
2218
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002219 rem = (slab_size - reserved) % size;
Christoph Lameter81819f02007-05-06 14:49:36 -07002220
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002221 if (rem <= slab_size / fract_leftover)
Christoph Lameter81819f02007-05-06 14:49:36 -07002222 break;
2223
2224 }
Christoph Lameter672bba32007-05-09 02:32:39 -07002225
Christoph Lameter81819f02007-05-06 14:49:36 -07002226 return order;
2227}
2228
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002229static inline int calculate_order(int size, int reserved)
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002230{
2231 int order;
2232 int min_objects;
2233 int fraction;
Zhang Yanmine8120ff2009-02-12 18:00:17 +02002234 int max_objects;
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002235
2236 /*
2237 * Attempt to find best configuration for a slab. This
2238 * works by first attempting to generate a layout with
2239 * the best configuration and backing off gradually.
2240 *
2241 * First we reduce the acceptable waste in a slab. Then
2242 * we reduce the minimum objects required in a slab.
2243 */
2244 min_objects = slub_min_objects;
Christoph Lameter9b2cd502008-04-14 19:11:41 +03002245 if (!min_objects)
2246 min_objects = 4 * (fls(nr_cpu_ids) + 1);
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002247 max_objects = order_objects(slub_max_order, size, reserved);
Zhang Yanmine8120ff2009-02-12 18:00:17 +02002248 min_objects = min(min_objects, max_objects);
2249
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002250 while (min_objects > 1) {
Christoph Lameterc124f5b2008-04-14 19:13:29 +03002251 fraction = 16;
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002252 while (fraction >= 4) {
2253 order = slab_order(size, min_objects,
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002254 slub_max_order, fraction, reserved);
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002255 if (order <= slub_max_order)
2256 return order;
2257 fraction /= 2;
2258 }
Amerigo Wang5086c389c2009-08-19 21:44:13 +03002259 min_objects--;
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002260 }
2261
2262 /*
2263 * We were unable to place multiple objects in a slab. Now
2264 * lets see if we can place a single object there.
2265 */
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002266 order = slab_order(size, 1, slub_max_order, 1, reserved);
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002267 if (order <= slub_max_order)
2268 return order;
2269
2270 /*
2271 * Doh this slab cannot be placed using slub_max_order.
2272 */
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002273 order = slab_order(size, 1, MAX_ORDER, 1, reserved);
David Rientjes818cf592009-04-23 09:58:22 +03002274 if (order < MAX_ORDER)
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002275 return order;
2276 return -ENOSYS;
2277}
2278
Christoph Lameter81819f02007-05-06 14:49:36 -07002279/*
Christoph Lameter672bba32007-05-09 02:32:39 -07002280 * Figure out what the alignment of the objects will be.
Christoph Lameter81819f02007-05-06 14:49:36 -07002281 */
2282static unsigned long calculate_alignment(unsigned long flags,
2283 unsigned long align, unsigned long size)
2284{
2285 /*
Christoph Lameter6446faa2008-02-15 23:45:26 -08002286 * If the user wants hardware cache aligned objects then follow that
2287 * suggestion if the object is sufficiently large.
Christoph Lameter81819f02007-05-06 14:49:36 -07002288 *
Christoph Lameter6446faa2008-02-15 23:45:26 -08002289 * The hardware cache alignment cannot override the specified
2290 * alignment though. If that is greater then use it.
Christoph Lameter81819f02007-05-06 14:49:36 -07002291 */
Nick Pigginb6210382008-03-05 14:05:56 -08002292 if (flags & SLAB_HWCACHE_ALIGN) {
2293 unsigned long ralign = cache_line_size();
2294 while (size <= ralign / 2)
2295 ralign /= 2;
2296 align = max(align, ralign);
2297 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002298
2299 if (align < ARCH_SLAB_MINALIGN)
Nick Pigginb6210382008-03-05 14:05:56 -08002300 align = ARCH_SLAB_MINALIGN;
Christoph Lameter81819f02007-05-06 14:49:36 -07002301
2302 return ALIGN(align, sizeof(void *));
2303}
2304
Pekka Enberg5595cff2008-08-05 09:28:47 +03002305static void
2306init_kmem_cache_node(struct kmem_cache_node *n, struct kmem_cache *s)
Christoph Lameter81819f02007-05-06 14:49:36 -07002307{
2308 n->nr_partial = 0;
Christoph Lameter81819f02007-05-06 14:49:36 -07002309 spin_lock_init(&n->list_lock);
2310 INIT_LIST_HEAD(&n->partial);
Christoph Lameter8ab13722007-07-17 04:03:32 -07002311#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter0f389ec2008-04-14 18:53:02 +03002312 atomic_long_set(&n->nr_slabs, 0);
Salman Qazi02b71b72008-09-11 12:25:41 -07002313 atomic_long_set(&n->total_objects, 0);
Christoph Lameter643b1132007-05-06 14:49:42 -07002314 INIT_LIST_HEAD(&n->full);
Christoph Lameter8ab13722007-07-17 04:03:32 -07002315#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07002316}
2317
Christoph Lameter55136592010-08-20 12:37:13 -05002318static inline int alloc_kmem_cache_cpus(struct kmem_cache *s)
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002319{
Christoph Lameter6c182dc2010-08-20 12:37:14 -05002320 BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE <
2321 SLUB_PAGE_SHIFT * sizeof(struct kmem_cache_cpu));
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002322
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002323 /*
Chris Metcalfd4d84fe2011-06-02 10:19:41 -04002324 * Must align to double word boundary for the double cmpxchg
2325 * instructions to work; see __pcpu_double_call_return_bool().
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002326 */
Chris Metcalfd4d84fe2011-06-02 10:19:41 -04002327 s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu),
2328 2 * sizeof(void *));
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002329
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002330 if (!s->cpu_slab)
2331 return 0;
2332
2333 init_kmem_cache_cpus(s);
2334
2335 return 1;
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002336}
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002337
Christoph Lameter51df1142010-08-20 12:37:15 -05002338static struct kmem_cache *kmem_cache_node;
2339
Christoph Lameter81819f02007-05-06 14:49:36 -07002340/*
2341 * No kmalloc_node yet so do it by hand. We know that this is the first
2342 * slab on the node for this slabcache. There are no concurrent accesses
2343 * possible.
2344 *
2345 * Note that this function only works on the kmalloc_node_cache
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002346 * when allocating for the kmalloc_node_cache. This is used for bootstrapping
2347 * memory on a fresh node that has no slab structures yet.
Christoph Lameter81819f02007-05-06 14:49:36 -07002348 */
Christoph Lameter55136592010-08-20 12:37:13 -05002349static void early_kmem_cache_node_alloc(int node)
Christoph Lameter81819f02007-05-06 14:49:36 -07002350{
2351 struct page *page;
2352 struct kmem_cache_node *n;
rootba84c732008-01-07 23:20:28 -08002353 unsigned long flags;
Christoph Lameter81819f02007-05-06 14:49:36 -07002354
Christoph Lameter51df1142010-08-20 12:37:15 -05002355 BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node));
Christoph Lameter81819f02007-05-06 14:49:36 -07002356
Christoph Lameter51df1142010-08-20 12:37:15 -05002357 page = new_slab(kmem_cache_node, GFP_NOWAIT, node);
Christoph Lameter81819f02007-05-06 14:49:36 -07002358
2359 BUG_ON(!page);
Christoph Lametera2f92ee2007-08-22 14:01:57 -07002360 if (page_to_nid(page) != node) {
2361 printk(KERN_ERR "SLUB: Unable to allocate memory from "
2362 "node %d\n", node);
2363 printk(KERN_ERR "SLUB: Allocating a useless per node structure "
2364 "in order to be able to continue\n");
2365 }
2366
Christoph Lameter81819f02007-05-06 14:49:36 -07002367 n = page->freelist;
2368 BUG_ON(!n);
Christoph Lameter51df1142010-08-20 12:37:15 -05002369 page->freelist = get_freepointer(kmem_cache_node, n);
Christoph Lameter81819f02007-05-06 14:49:36 -07002370 page->inuse++;
Christoph Lameter51df1142010-08-20 12:37:15 -05002371 kmem_cache_node->node[node] = n;
Christoph Lameter8ab13722007-07-17 04:03:32 -07002372#ifdef CONFIG_SLUB_DEBUG
Christoph Lameterf7cb1932010-09-29 07:15:01 -05002373 init_object(kmem_cache_node, n, SLUB_RED_ACTIVE);
Christoph Lameter51df1142010-08-20 12:37:15 -05002374 init_tracking(kmem_cache_node, n);
Christoph Lameter8ab13722007-07-17 04:03:32 -07002375#endif
Christoph Lameter51df1142010-08-20 12:37:15 -05002376 init_kmem_cache_node(n, kmem_cache_node);
2377 inc_slabs_node(kmem_cache_node, node, page->objects);
Christoph Lameter6446faa2008-02-15 23:45:26 -08002378
rootba84c732008-01-07 23:20:28 -08002379 /*
2380 * lockdep requires consistent irq usage for each lock
2381 * so even though there cannot be a race this early in
2382 * the boot sequence, we still disable irqs.
2383 */
2384 local_irq_save(flags);
Christoph Lameter7c2e1322008-01-07 23:20:27 -08002385 add_partial(n, page, 0);
rootba84c732008-01-07 23:20:28 -08002386 local_irq_restore(flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07002387}
2388
2389static void free_kmem_cache_nodes(struct kmem_cache *s)
2390{
2391 int node;
2392
Christoph Lameterf64dc582007-10-16 01:25:33 -07002393 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002394 struct kmem_cache_node *n = s->node[node];
Christoph Lameter51df1142010-08-20 12:37:15 -05002395
Alexander Duyck73367bd2010-05-21 14:41:35 -07002396 if (n)
Christoph Lameter51df1142010-08-20 12:37:15 -05002397 kmem_cache_free(kmem_cache_node, n);
2398
Christoph Lameter81819f02007-05-06 14:49:36 -07002399 s->node[node] = NULL;
2400 }
2401}
2402
Christoph Lameter55136592010-08-20 12:37:13 -05002403static int init_kmem_cache_nodes(struct kmem_cache *s)
Christoph Lameter81819f02007-05-06 14:49:36 -07002404{
2405 int node;
Christoph Lameter81819f02007-05-06 14:49:36 -07002406
Christoph Lameterf64dc582007-10-16 01:25:33 -07002407 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002408 struct kmem_cache_node *n;
2409
Alexander Duyck73367bd2010-05-21 14:41:35 -07002410 if (slab_state == DOWN) {
Christoph Lameter55136592010-08-20 12:37:13 -05002411 early_kmem_cache_node_alloc(node);
Alexander Duyck73367bd2010-05-21 14:41:35 -07002412 continue;
Christoph Lameter81819f02007-05-06 14:49:36 -07002413 }
Christoph Lameter51df1142010-08-20 12:37:15 -05002414 n = kmem_cache_alloc_node(kmem_cache_node,
Christoph Lameter55136592010-08-20 12:37:13 -05002415 GFP_KERNEL, node);
Alexander Duyck73367bd2010-05-21 14:41:35 -07002416
2417 if (!n) {
2418 free_kmem_cache_nodes(s);
2419 return 0;
2420 }
2421
Christoph Lameter81819f02007-05-06 14:49:36 -07002422 s->node[node] = n;
Pekka Enberg5595cff2008-08-05 09:28:47 +03002423 init_kmem_cache_node(n, s);
Christoph Lameter81819f02007-05-06 14:49:36 -07002424 }
2425 return 1;
2426}
Christoph Lameter81819f02007-05-06 14:49:36 -07002427
David Rientjesc0bdb232009-02-25 09:16:35 +02002428static void set_min_partial(struct kmem_cache *s, unsigned long min)
David Rientjes3b89d7d2009-02-22 17:40:07 -08002429{
2430 if (min < MIN_PARTIAL)
2431 min = MIN_PARTIAL;
2432 else if (min > MAX_PARTIAL)
2433 min = MAX_PARTIAL;
2434 s->min_partial = min;
2435}
2436
Christoph Lameter81819f02007-05-06 14:49:36 -07002437/*
2438 * calculate_sizes() determines the order and the distribution of data within
2439 * a slab object.
2440 */
Christoph Lameter06b285d2008-04-14 19:11:41 +03002441static int calculate_sizes(struct kmem_cache *s, int forced_order)
Christoph Lameter81819f02007-05-06 14:49:36 -07002442{
2443 unsigned long flags = s->flags;
2444 unsigned long size = s->objsize;
2445 unsigned long align = s->align;
Christoph Lameter834f3d12008-04-14 19:11:31 +03002446 int order;
Christoph Lameter81819f02007-05-06 14:49:36 -07002447
2448 /*
Christoph Lameterd8b42bf2008-02-15 23:45:25 -08002449 * Round up object size to the next word boundary. We can only
2450 * place the free pointer at word boundaries and this determines
2451 * the possible location of the free pointer.
2452 */
2453 size = ALIGN(size, sizeof(void *));
2454
2455#ifdef CONFIG_SLUB_DEBUG
2456 /*
Christoph Lameter81819f02007-05-06 14:49:36 -07002457 * Determine if we can poison the object itself. If the user of
2458 * the slab may touch the object after free or before allocation
2459 * then we should never poison the object itself.
2460 */
2461 if ((flags & SLAB_POISON) && !(flags & SLAB_DESTROY_BY_RCU) &&
Christoph Lameterc59def92007-05-16 22:10:50 -07002462 !s->ctor)
Christoph Lameter81819f02007-05-06 14:49:36 -07002463 s->flags |= __OBJECT_POISON;
2464 else
2465 s->flags &= ~__OBJECT_POISON;
2466
Christoph Lameter81819f02007-05-06 14:49:36 -07002467
2468 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07002469 * If we are Redzoning then check if there is some space between the
Christoph Lameter81819f02007-05-06 14:49:36 -07002470 * end of the object and the free pointer. If not then add an
Christoph Lameter672bba32007-05-09 02:32:39 -07002471 * additional word to have some bytes to store Redzone information.
Christoph Lameter81819f02007-05-06 14:49:36 -07002472 */
2473 if ((flags & SLAB_RED_ZONE) && size == s->objsize)
2474 size += sizeof(void *);
Christoph Lameter41ecc552007-05-09 02:32:44 -07002475#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07002476
2477 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07002478 * With that we have determined the number of bytes in actual use
2479 * by the object. This is the potential offset to the free pointer.
Christoph Lameter81819f02007-05-06 14:49:36 -07002480 */
2481 s->inuse = size;
2482
2483 if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) ||
Christoph Lameterc59def92007-05-16 22:10:50 -07002484 s->ctor)) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002485 /*
2486 * Relocate free pointer after the object if it is not
2487 * permitted to overwrite the first word of the object on
2488 * kmem_cache_free.
2489 *
2490 * This is the case if we do RCU, have a constructor or
2491 * destructor or are poisoning the objects.
2492 */
2493 s->offset = size;
2494 size += sizeof(void *);
2495 }
2496
Christoph Lameterc12b3c62007-05-23 13:57:31 -07002497#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter81819f02007-05-06 14:49:36 -07002498 if (flags & SLAB_STORE_USER)
2499 /*
2500 * Need to store information about allocs and frees after
2501 * the object.
2502 */
2503 size += 2 * sizeof(struct track);
2504
Christoph Lameterbe7b3fb2007-05-09 02:32:36 -07002505 if (flags & SLAB_RED_ZONE)
Christoph Lameter81819f02007-05-06 14:49:36 -07002506 /*
2507 * Add some empty padding so that we can catch
2508 * overwrites from earlier objects rather than let
2509 * tracking information or the free pointer be
Frederik Schwarzer0211a9c2008-12-29 22:14:56 +01002510 * corrupted if a user writes before the start
Christoph Lameter81819f02007-05-06 14:49:36 -07002511 * of the object.
2512 */
2513 size += sizeof(void *);
Christoph Lameter41ecc552007-05-09 02:32:44 -07002514#endif
Christoph Lameter672bba32007-05-09 02:32:39 -07002515
Christoph Lameter81819f02007-05-06 14:49:36 -07002516 /*
2517 * Determine the alignment based on various parameters that the
Christoph Lameter65c02d42007-05-09 02:32:35 -07002518 * user specified and the dynamic determination of cache line size
2519 * on bootup.
Christoph Lameter81819f02007-05-06 14:49:36 -07002520 */
2521 align = calculate_alignment(flags, align, s->objsize);
Zhang, Yanmindcb0ce12009-07-30 11:28:11 +08002522 s->align = align;
Christoph Lameter81819f02007-05-06 14:49:36 -07002523
2524 /*
2525 * SLUB stores one object immediately after another beginning from
2526 * offset 0. In order to align the objects we have to simply size
2527 * each object to conform to the alignment.
2528 */
2529 size = ALIGN(size, align);
2530 s->size = size;
Christoph Lameter06b285d2008-04-14 19:11:41 +03002531 if (forced_order >= 0)
2532 order = forced_order;
2533 else
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002534 order = calculate_order(size, s->reserved);
Christoph Lameter81819f02007-05-06 14:49:36 -07002535
Christoph Lameter834f3d12008-04-14 19:11:31 +03002536 if (order < 0)
Christoph Lameter81819f02007-05-06 14:49:36 -07002537 return 0;
2538
Christoph Lameterb7a49f02008-02-14 14:21:32 -08002539 s->allocflags = 0;
Christoph Lameter834f3d12008-04-14 19:11:31 +03002540 if (order)
Christoph Lameterb7a49f02008-02-14 14:21:32 -08002541 s->allocflags |= __GFP_COMP;
2542
2543 if (s->flags & SLAB_CACHE_DMA)
2544 s->allocflags |= SLUB_DMA;
2545
2546 if (s->flags & SLAB_RECLAIM_ACCOUNT)
2547 s->allocflags |= __GFP_RECLAIMABLE;
2548
Christoph Lameter81819f02007-05-06 14:49:36 -07002549 /*
2550 * Determine the number of objects per slab
2551 */
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002552 s->oo = oo_make(order, size, s->reserved);
2553 s->min = oo_make(get_order(size), size, s->reserved);
Christoph Lameter205ab992008-04-14 19:11:40 +03002554 if (oo_objects(s->oo) > oo_objects(s->max))
2555 s->max = s->oo;
Christoph Lameter81819f02007-05-06 14:49:36 -07002556
Christoph Lameter834f3d12008-04-14 19:11:31 +03002557 return !!oo_objects(s->oo);
Christoph Lameter81819f02007-05-06 14:49:36 -07002558
2559}
2560
Christoph Lameter55136592010-08-20 12:37:13 -05002561static int kmem_cache_open(struct kmem_cache *s,
Christoph Lameter81819f02007-05-06 14:49:36 -07002562 const char *name, size_t size,
2563 size_t align, unsigned long flags,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07002564 void (*ctor)(void *))
Christoph Lameter81819f02007-05-06 14:49:36 -07002565{
2566 memset(s, 0, kmem_size);
2567 s->name = name;
2568 s->ctor = ctor;
Christoph Lameter81819f02007-05-06 14:49:36 -07002569 s->objsize = size;
Christoph Lameter81819f02007-05-06 14:49:36 -07002570 s->align = align;
Christoph Lameterba0268a2007-09-11 15:24:11 -07002571 s->flags = kmem_cache_flags(size, flags, name, ctor);
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002572 s->reserved = 0;
Christoph Lameter81819f02007-05-06 14:49:36 -07002573
Lai Jiangshanda9a6382011-03-10 15:22:00 +08002574 if (need_reserve_slab_rcu && (s->flags & SLAB_DESTROY_BY_RCU))
2575 s->reserved = sizeof(struct rcu_head);
Christoph Lameter81819f02007-05-06 14:49:36 -07002576
Christoph Lameter06b285d2008-04-14 19:11:41 +03002577 if (!calculate_sizes(s, -1))
Christoph Lameter81819f02007-05-06 14:49:36 -07002578 goto error;
David Rientjes3de47212009-07-27 18:30:35 -07002579 if (disable_higher_order_debug) {
2580 /*
2581 * Disable debugging flags that store metadata if the min slab
2582 * order increased.
2583 */
2584 if (get_order(s->size) > get_order(s->objsize)) {
2585 s->flags &= ~DEBUG_METADATA_FLAGS;
2586 s->offset = 0;
2587 if (!calculate_sizes(s, -1))
2588 goto error;
2589 }
2590 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002591
David Rientjes3b89d7d2009-02-22 17:40:07 -08002592 /*
2593 * The larger the object size is, the more pages we want on the partial
2594 * list to avoid pounding the page allocator excessively.
2595 */
David Rientjesc0bdb232009-02-25 09:16:35 +02002596 set_min_partial(s, ilog2(s->size));
Christoph Lameter81819f02007-05-06 14:49:36 -07002597 s->refcount = 1;
2598#ifdef CONFIG_NUMA
Christoph Lametere2cb96b2008-08-19 08:51:22 -05002599 s->remote_node_defrag_ratio = 1000;
Christoph Lameter81819f02007-05-06 14:49:36 -07002600#endif
Christoph Lameter55136592010-08-20 12:37:13 -05002601 if (!init_kmem_cache_nodes(s))
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002602 goto error;
Christoph Lameter81819f02007-05-06 14:49:36 -07002603
Christoph Lameter55136592010-08-20 12:37:13 -05002604 if (alloc_kmem_cache_cpus(s))
Christoph Lameter81819f02007-05-06 14:49:36 -07002605 return 1;
Christoph Lameterff120592009-12-18 16:26:22 -06002606
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002607 free_kmem_cache_nodes(s);
Christoph Lameter81819f02007-05-06 14:49:36 -07002608error:
2609 if (flags & SLAB_PANIC)
2610 panic("Cannot create slab %s size=%lu realsize=%u "
2611 "order=%u offset=%u flags=%lx\n",
Christoph Lameter834f3d12008-04-14 19:11:31 +03002612 s->name, (unsigned long)size, s->size, oo_order(s->oo),
Christoph Lameter81819f02007-05-06 14:49:36 -07002613 s->offset, flags);
2614 return 0;
2615}
Christoph Lameter81819f02007-05-06 14:49:36 -07002616
2617/*
Christoph Lameter81819f02007-05-06 14:49:36 -07002618 * Determine the size of a slab object
2619 */
2620unsigned int kmem_cache_size(struct kmem_cache *s)
2621{
2622 return s->objsize;
2623}
2624EXPORT_SYMBOL(kmem_cache_size);
2625
Christoph Lameter33b12c32008-04-25 12:22:43 -07002626static void list_slab_objects(struct kmem_cache *s, struct page *page,
2627 const char *text)
Christoph Lameter81819f02007-05-06 14:49:36 -07002628{
Christoph Lameter33b12c32008-04-25 12:22:43 -07002629#ifdef CONFIG_SLUB_DEBUG
2630 void *addr = page_address(page);
2631 void *p;
Namhyung Kima5dd5c12010-09-29 21:02:13 +09002632 unsigned long *map = kzalloc(BITS_TO_LONGS(page->objects) *
2633 sizeof(long), GFP_ATOMIC);
Eric Dumazetbbd7d572010-03-24 22:25:47 +01002634 if (!map)
2635 return;
Christoph Lameter33b12c32008-04-25 12:22:43 -07002636 slab_err(s, page, "%s", text);
2637 slab_lock(page);
Christoph Lameter33b12c32008-04-25 12:22:43 -07002638
Christoph Lameter5f80b132011-04-15 14:48:13 -05002639 get_map(s, page, map);
Christoph Lameter33b12c32008-04-25 12:22:43 -07002640 for_each_object(p, s, addr, page->objects) {
2641
2642 if (!test_bit(slab_index(p, s, addr), map)) {
2643 printk(KERN_ERR "INFO: Object 0x%p @offset=%tu\n",
2644 p, p - addr);
2645 print_tracking(s, p);
2646 }
2647 }
2648 slab_unlock(page);
Eric Dumazetbbd7d572010-03-24 22:25:47 +01002649 kfree(map);
Christoph Lameter33b12c32008-04-25 12:22:43 -07002650#endif
2651}
2652
Christoph Lameter81819f02007-05-06 14:49:36 -07002653/*
Christoph Lameter599870b2008-04-23 12:36:52 -07002654 * Attempt to free all partial slabs on a node.
Christoph Lameter81819f02007-05-06 14:49:36 -07002655 */
Christoph Lameter599870b2008-04-23 12:36:52 -07002656static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
Christoph Lameter81819f02007-05-06 14:49:36 -07002657{
Christoph Lameter81819f02007-05-06 14:49:36 -07002658 unsigned long flags;
2659 struct page *page, *h;
2660
2661 spin_lock_irqsave(&n->list_lock, flags);
Christoph Lameter33b12c32008-04-25 12:22:43 -07002662 list_for_each_entry_safe(page, h, &n->partial, lru) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002663 if (!page->inuse) {
Christoph Lameter62e346a2010-09-28 08:10:28 -05002664 __remove_partial(n, page);
Christoph Lameter81819f02007-05-06 14:49:36 -07002665 discard_slab(s, page);
Christoph Lameter33b12c32008-04-25 12:22:43 -07002666 } else {
2667 list_slab_objects(s, page,
2668 "Objects remaining on kmem_cache_close()");
Christoph Lameter599870b2008-04-23 12:36:52 -07002669 }
Christoph Lameter33b12c32008-04-25 12:22:43 -07002670 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002671 spin_unlock_irqrestore(&n->list_lock, flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07002672}
2673
2674/*
Christoph Lameter672bba32007-05-09 02:32:39 -07002675 * Release all resources used by a slab cache.
Christoph Lameter81819f02007-05-06 14:49:36 -07002676 */
Christoph Lameter0c710012007-07-17 04:03:24 -07002677static inline int kmem_cache_close(struct kmem_cache *s)
Christoph Lameter81819f02007-05-06 14:49:36 -07002678{
2679 int node;
2680
2681 flush_all(s);
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002682 free_percpu(s->cpu_slab);
Christoph Lameter81819f02007-05-06 14:49:36 -07002683 /* Attempt to free all objects */
Christoph Lameterf64dc582007-10-16 01:25:33 -07002684 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002685 struct kmem_cache_node *n = get_node(s, node);
2686
Christoph Lameter599870b2008-04-23 12:36:52 -07002687 free_partial(s, n);
2688 if (n->nr_partial || slabs_node(s, node))
Christoph Lameter81819f02007-05-06 14:49:36 -07002689 return 1;
2690 }
2691 free_kmem_cache_nodes(s);
2692 return 0;
2693}
2694
2695/*
2696 * Close a cache and release the kmem_cache structure
2697 * (must be used for caches created using kmem_cache_create)
2698 */
2699void kmem_cache_destroy(struct kmem_cache *s)
2700{
2701 down_write(&slub_lock);
2702 s->refcount--;
2703 if (!s->refcount) {
2704 list_del(&s->list);
Pekka Enbergd629d812008-04-23 22:31:08 +03002705 if (kmem_cache_close(s)) {
2706 printk(KERN_ERR "SLUB %s: %s called for cache that "
2707 "still has objects.\n", s->name, __func__);
2708 dump_stack();
2709 }
Eric Dumazetd76b1592009-09-03 22:38:59 +03002710 if (s->flags & SLAB_DESTROY_BY_RCU)
2711 rcu_barrier();
Christoph Lameter81819f02007-05-06 14:49:36 -07002712 sysfs_slab_remove(s);
Christoph Lameter2bce6482010-07-19 11:39:11 -05002713 }
2714 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07002715}
2716EXPORT_SYMBOL(kmem_cache_destroy);
2717
2718/********************************************************************
2719 * Kmalloc subsystem
2720 *******************************************************************/
2721
Christoph Lameter51df1142010-08-20 12:37:15 -05002722struct kmem_cache *kmalloc_caches[SLUB_PAGE_SHIFT];
Christoph Lameter81819f02007-05-06 14:49:36 -07002723EXPORT_SYMBOL(kmalloc_caches);
2724
Christoph Lameter51df1142010-08-20 12:37:15 -05002725static struct kmem_cache *kmem_cache;
2726
Christoph Lameter55136592010-08-20 12:37:13 -05002727#ifdef CONFIG_ZONE_DMA
Christoph Lameter51df1142010-08-20 12:37:15 -05002728static struct kmem_cache *kmalloc_dma_caches[SLUB_PAGE_SHIFT];
Christoph Lameter55136592010-08-20 12:37:13 -05002729#endif
2730
Christoph Lameter81819f02007-05-06 14:49:36 -07002731static int __init setup_slub_min_order(char *str)
2732{
Pekka Enberg06428782008-01-07 23:20:27 -08002733 get_option(&str, &slub_min_order);
Christoph Lameter81819f02007-05-06 14:49:36 -07002734
2735 return 1;
2736}
2737
2738__setup("slub_min_order=", setup_slub_min_order);
2739
2740static int __init setup_slub_max_order(char *str)
2741{
Pekka Enberg06428782008-01-07 23:20:27 -08002742 get_option(&str, &slub_max_order);
David Rientjes818cf592009-04-23 09:58:22 +03002743 slub_max_order = min(slub_max_order, MAX_ORDER - 1);
Christoph Lameter81819f02007-05-06 14:49:36 -07002744
2745 return 1;
2746}
2747
2748__setup("slub_max_order=", setup_slub_max_order);
2749
2750static int __init setup_slub_min_objects(char *str)
2751{
Pekka Enberg06428782008-01-07 23:20:27 -08002752 get_option(&str, &slub_min_objects);
Christoph Lameter81819f02007-05-06 14:49:36 -07002753
2754 return 1;
2755}
2756
2757__setup("slub_min_objects=", setup_slub_min_objects);
2758
2759static int __init setup_slub_nomerge(char *str)
2760{
2761 slub_nomerge = 1;
2762 return 1;
2763}
2764
2765__setup("slub_nomerge", setup_slub_nomerge);
2766
Christoph Lameter51df1142010-08-20 12:37:15 -05002767static struct kmem_cache *__init create_kmalloc_cache(const char *name,
2768 int size, unsigned int flags)
Christoph Lameter81819f02007-05-06 14:49:36 -07002769{
Christoph Lameter51df1142010-08-20 12:37:15 -05002770 struct kmem_cache *s;
2771
2772 s = kmem_cache_alloc(kmem_cache, GFP_NOWAIT);
2773
Pekka Enberg83b519e2009-06-10 19:40:04 +03002774 /*
2775 * This function is called with IRQs disabled during early-boot on
2776 * single CPU so there's no need to take slub_lock here.
2777 */
Christoph Lameter55136592010-08-20 12:37:13 -05002778 if (!kmem_cache_open(s, name, size, ARCH_KMALLOC_MINALIGN,
Christoph Lameter319d1e22008-04-14 19:11:41 +03002779 flags, NULL))
Christoph Lameter81819f02007-05-06 14:49:36 -07002780 goto panic;
2781
2782 list_add(&s->list, &slab_caches);
Christoph Lameter51df1142010-08-20 12:37:15 -05002783 return s;
Christoph Lameter81819f02007-05-06 14:49:36 -07002784
2785panic:
2786 panic("Creation of kmalloc slab %s size=%d failed.\n", name, size);
Christoph Lameter51df1142010-08-20 12:37:15 -05002787 return NULL;
Christoph Lameter81819f02007-05-06 14:49:36 -07002788}
2789
Christoph Lameterf1b26332007-07-17 04:03:26 -07002790/*
2791 * Conversion table for small slabs sizes / 8 to the index in the
2792 * kmalloc array. This is necessary for slabs < 192 since we have non power
2793 * of two cache sizes there. The size of larger slabs can be determined using
2794 * fls.
2795 */
2796static s8 size_index[24] = {
2797 3, /* 8 */
2798 4, /* 16 */
2799 5, /* 24 */
2800 5, /* 32 */
2801 6, /* 40 */
2802 6, /* 48 */
2803 6, /* 56 */
2804 6, /* 64 */
2805 1, /* 72 */
2806 1, /* 80 */
2807 1, /* 88 */
2808 1, /* 96 */
2809 7, /* 104 */
2810 7, /* 112 */
2811 7, /* 120 */
2812 7, /* 128 */
2813 2, /* 136 */
2814 2, /* 144 */
2815 2, /* 152 */
2816 2, /* 160 */
2817 2, /* 168 */
2818 2, /* 176 */
2819 2, /* 184 */
2820 2 /* 192 */
2821};
2822
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03002823static inline int size_index_elem(size_t bytes)
2824{
2825 return (bytes - 1) / 8;
2826}
2827
Christoph Lameter81819f02007-05-06 14:49:36 -07002828static struct kmem_cache *get_slab(size_t size, gfp_t flags)
2829{
Christoph Lameterf1b26332007-07-17 04:03:26 -07002830 int index;
Christoph Lameter81819f02007-05-06 14:49:36 -07002831
Christoph Lameterf1b26332007-07-17 04:03:26 -07002832 if (size <= 192) {
2833 if (!size)
2834 return ZERO_SIZE_PTR;
Christoph Lameter81819f02007-05-06 14:49:36 -07002835
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03002836 index = size_index[size_index_elem(size)];
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002837 } else
Christoph Lameterf1b26332007-07-17 04:03:26 -07002838 index = fls(size - 1);
Christoph Lameter81819f02007-05-06 14:49:36 -07002839
2840#ifdef CONFIG_ZONE_DMA
Christoph Lameterf1b26332007-07-17 04:03:26 -07002841 if (unlikely((flags & SLUB_DMA)))
Christoph Lameter51df1142010-08-20 12:37:15 -05002842 return kmalloc_dma_caches[index];
Christoph Lameterf1b26332007-07-17 04:03:26 -07002843
Christoph Lameter81819f02007-05-06 14:49:36 -07002844#endif
Christoph Lameter51df1142010-08-20 12:37:15 -05002845 return kmalloc_caches[index];
Christoph Lameter81819f02007-05-06 14:49:36 -07002846}
2847
2848void *__kmalloc(size_t size, gfp_t flags)
2849{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002850 struct kmem_cache *s;
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002851 void *ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002852
Christoph Lameterffadd4d2009-02-17 12:05:07 -05002853 if (unlikely(size > SLUB_MAX_SIZE))
Pekka Enbergeada35e2008-02-11 22:47:46 +02002854 return kmalloc_large(size, flags);
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002855
2856 s = get_slab(size, flags);
2857
2858 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07002859 return s;
2860
Christoph Lameter2154a332010-07-09 14:07:10 -05002861 ret = slab_alloc(s, flags, NUMA_NO_NODE, _RET_IP_);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002862
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02002863 trace_kmalloc(_RET_IP_, ret, size, s->size, flags);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002864
2865 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002866}
2867EXPORT_SYMBOL(__kmalloc);
2868
Namhyung Kim5d1f57e2010-09-29 21:02:15 +09002869#ifdef CONFIG_NUMA
Christoph Lameterf619cfe2008-03-01 13:56:40 -08002870static void *kmalloc_large_node(size_t size, gfp_t flags, int node)
2871{
Vegard Nossumb1eeab62008-11-25 16:55:53 +01002872 struct page *page;
Catalin Marinase4f7c0b42009-07-07 10:32:59 +01002873 void *ptr = NULL;
Christoph Lameterf619cfe2008-03-01 13:56:40 -08002874
Vegard Nossumb1eeab62008-11-25 16:55:53 +01002875 flags |= __GFP_COMP | __GFP_NOTRACK;
2876 page = alloc_pages_node(node, flags, get_order(size));
Christoph Lameterf619cfe2008-03-01 13:56:40 -08002877 if (page)
Catalin Marinase4f7c0b42009-07-07 10:32:59 +01002878 ptr = page_address(page);
2879
2880 kmemleak_alloc(ptr, size, 1, flags);
2881 return ptr;
Christoph Lameterf619cfe2008-03-01 13:56:40 -08002882}
2883
Christoph Lameter81819f02007-05-06 14:49:36 -07002884void *__kmalloc_node(size_t size, gfp_t flags, int node)
2885{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002886 struct kmem_cache *s;
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002887 void *ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002888
Ingo Molnar057685c2009-02-20 12:15:30 +01002889 if (unlikely(size > SLUB_MAX_SIZE)) {
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002890 ret = kmalloc_large_node(size, flags, node);
2891
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02002892 trace_kmalloc_node(_RET_IP_, ret,
2893 size, PAGE_SIZE << get_order(size),
2894 flags, node);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002895
2896 return ret;
2897 }
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002898
2899 s = get_slab(size, flags);
2900
2901 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07002902 return s;
2903
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002904 ret = slab_alloc(s, flags, node, _RET_IP_);
2905
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02002906 trace_kmalloc_node(_RET_IP_, ret, size, s->size, flags, node);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002907
2908 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002909}
2910EXPORT_SYMBOL(__kmalloc_node);
2911#endif
2912
2913size_t ksize(const void *object)
2914{
Christoph Lameter272c1d22007-06-08 13:46:49 -07002915 struct page *page;
Christoph Lameter81819f02007-05-06 14:49:36 -07002916
Christoph Lameteref8b4522007-10-16 01:24:46 -07002917 if (unlikely(object == ZERO_SIZE_PTR))
Christoph Lameter272c1d22007-06-08 13:46:49 -07002918 return 0;
2919
Vegard Nossum294a80a2007-12-04 23:45:30 -08002920 page = virt_to_head_page(object);
Vegard Nossum294a80a2007-12-04 23:45:30 -08002921
Pekka Enberg76994412008-05-22 19:22:25 +03002922 if (unlikely(!PageSlab(page))) {
2923 WARN_ON(!PageCompound(page));
Vegard Nossum294a80a2007-12-04 23:45:30 -08002924 return PAGE_SIZE << compound_order(page);
Pekka Enberg76994412008-05-22 19:22:25 +03002925 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002926
Eric Dumazetb3d41882011-02-14 18:35:22 +01002927 return slab_ksize(page->slab);
Christoph Lameter81819f02007-05-06 14:49:36 -07002928}
Kirill A. Shutemovb1aabec2009-02-10 15:21:44 +02002929EXPORT_SYMBOL(ksize);
Christoph Lameter81819f02007-05-06 14:49:36 -07002930
2931void kfree(const void *x)
2932{
Christoph Lameter81819f02007-05-06 14:49:36 -07002933 struct page *page;
Christoph Lameter5bb983b2008-02-07 17:47:41 -08002934 void *object = (void *)x;
Christoph Lameter81819f02007-05-06 14:49:36 -07002935
Pekka Enberg2121db72009-03-25 11:05:57 +02002936 trace_kfree(_RET_IP_, x);
2937
Satyam Sharma2408c552007-10-16 01:24:44 -07002938 if (unlikely(ZERO_OR_NULL_PTR(x)))
Christoph Lameter81819f02007-05-06 14:49:36 -07002939 return;
2940
Christoph Lameterb49af682007-05-06 14:49:41 -07002941 page = virt_to_head_page(x);
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002942 if (unlikely(!PageSlab(page))) {
Christoph Lameter09375022008-05-28 10:32:22 -07002943 BUG_ON(!PageCompound(page));
Catalin Marinase4f7c0b42009-07-07 10:32:59 +01002944 kmemleak_free(x);
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002945 put_page(page);
2946 return;
2947 }
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03002948 slab_free(page->slab, page, object, _RET_IP_);
Christoph Lameter81819f02007-05-06 14:49:36 -07002949}
2950EXPORT_SYMBOL(kfree);
2951
Christoph Lameter2086d262007-05-06 14:49:46 -07002952/*
Christoph Lameter672bba32007-05-09 02:32:39 -07002953 * kmem_cache_shrink removes empty slabs from the partial lists and sorts
2954 * the remaining slabs by the number of items in use. The slabs with the
2955 * most items in use come first. New allocations will then fill those up
2956 * and thus they can be removed from the partial lists.
2957 *
2958 * The slabs with the least items are placed last. This results in them
2959 * being allocated from last increasing the chance that the last objects
2960 * are freed in them.
Christoph Lameter2086d262007-05-06 14:49:46 -07002961 */
2962int kmem_cache_shrink(struct kmem_cache *s)
2963{
2964 int node;
2965 int i;
2966 struct kmem_cache_node *n;
2967 struct page *page;
2968 struct page *t;
Christoph Lameter205ab992008-04-14 19:11:40 +03002969 int objects = oo_objects(s->max);
Christoph Lameter2086d262007-05-06 14:49:46 -07002970 struct list_head *slabs_by_inuse =
Christoph Lameter834f3d12008-04-14 19:11:31 +03002971 kmalloc(sizeof(struct list_head) * objects, GFP_KERNEL);
Christoph Lameter2086d262007-05-06 14:49:46 -07002972 unsigned long flags;
2973
2974 if (!slabs_by_inuse)
2975 return -ENOMEM;
2976
2977 flush_all(s);
Christoph Lameterf64dc582007-10-16 01:25:33 -07002978 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter2086d262007-05-06 14:49:46 -07002979 n = get_node(s, node);
2980
2981 if (!n->nr_partial)
2982 continue;
2983
Christoph Lameter834f3d12008-04-14 19:11:31 +03002984 for (i = 0; i < objects; i++)
Christoph Lameter2086d262007-05-06 14:49:46 -07002985 INIT_LIST_HEAD(slabs_by_inuse + i);
2986
2987 spin_lock_irqsave(&n->list_lock, flags);
2988
2989 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07002990 * Build lists indexed by the items in use in each slab.
Christoph Lameter2086d262007-05-06 14:49:46 -07002991 *
Christoph Lameter672bba32007-05-09 02:32:39 -07002992 * Note that concurrent frees may occur while we hold the
2993 * list_lock. page->inuse here is the upper limit.
Christoph Lameter2086d262007-05-06 14:49:46 -07002994 */
2995 list_for_each_entry_safe(page, t, &n->partial, lru) {
2996 if (!page->inuse && slab_trylock(page)) {
2997 /*
2998 * Must hold slab lock here because slab_free
2999 * may have freed the last object and be
3000 * waiting to release the slab.
3001 */
Christoph Lameter62e346a2010-09-28 08:10:28 -05003002 __remove_partial(n, page);
Christoph Lameter2086d262007-05-06 14:49:46 -07003003 slab_unlock(page);
3004 discard_slab(s, page);
3005 } else {
Christoph Lameterfcda3d82007-07-30 13:06:46 -07003006 list_move(&page->lru,
3007 slabs_by_inuse + page->inuse);
Christoph Lameter2086d262007-05-06 14:49:46 -07003008 }
3009 }
3010
Christoph Lameter2086d262007-05-06 14:49:46 -07003011 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07003012 * Rebuild the partial list with the slabs filled up most
3013 * first and the least used slabs at the end.
Christoph Lameter2086d262007-05-06 14:49:46 -07003014 */
Christoph Lameter834f3d12008-04-14 19:11:31 +03003015 for (i = objects - 1; i >= 0; i--)
Christoph Lameter2086d262007-05-06 14:49:46 -07003016 list_splice(slabs_by_inuse + i, n->partial.prev);
3017
Christoph Lameter2086d262007-05-06 14:49:46 -07003018 spin_unlock_irqrestore(&n->list_lock, flags);
3019 }
3020
3021 kfree(slabs_by_inuse);
3022 return 0;
3023}
3024EXPORT_SYMBOL(kmem_cache_shrink);
3025
Pekka Enberg92a5bbc2010-10-06 16:58:16 +03003026#if defined(CONFIG_MEMORY_HOTPLUG)
Yasunori Gotob9049e22007-10-21 16:41:37 -07003027static int slab_mem_going_offline_callback(void *arg)
3028{
3029 struct kmem_cache *s;
3030
3031 down_read(&slub_lock);
3032 list_for_each_entry(s, &slab_caches, list)
3033 kmem_cache_shrink(s);
3034 up_read(&slub_lock);
3035
3036 return 0;
3037}
3038
3039static void slab_mem_offline_callback(void *arg)
3040{
3041 struct kmem_cache_node *n;
3042 struct kmem_cache *s;
3043 struct memory_notify *marg = arg;
3044 int offline_node;
3045
3046 offline_node = marg->status_change_nid;
3047
3048 /*
3049 * If the node still has available memory. we need kmem_cache_node
3050 * for it yet.
3051 */
3052 if (offline_node < 0)
3053 return;
3054
3055 down_read(&slub_lock);
3056 list_for_each_entry(s, &slab_caches, list) {
3057 n = get_node(s, offline_node);
3058 if (n) {
3059 /*
3060 * if n->nr_slabs > 0, slabs still exist on the node
3061 * that is going down. We were unable to free them,
Adam Buchbinderc9404c92009-12-18 15:40:42 -05003062 * and offline_pages() function shouldn't call this
Yasunori Gotob9049e22007-10-21 16:41:37 -07003063 * callback. So, we must fail.
3064 */
Christoph Lameter0f389ec2008-04-14 18:53:02 +03003065 BUG_ON(slabs_node(s, offline_node));
Yasunori Gotob9049e22007-10-21 16:41:37 -07003066
3067 s->node[offline_node] = NULL;
Christoph Lameter8de66a02010-08-25 14:51:14 -05003068 kmem_cache_free(kmem_cache_node, n);
Yasunori Gotob9049e22007-10-21 16:41:37 -07003069 }
3070 }
3071 up_read(&slub_lock);
3072}
3073
3074static int slab_mem_going_online_callback(void *arg)
3075{
3076 struct kmem_cache_node *n;
3077 struct kmem_cache *s;
3078 struct memory_notify *marg = arg;
3079 int nid = marg->status_change_nid;
3080 int ret = 0;
3081
3082 /*
3083 * If the node's memory is already available, then kmem_cache_node is
3084 * already created. Nothing to do.
3085 */
3086 if (nid < 0)
3087 return 0;
3088
3089 /*
Christoph Lameter0121c6192008-04-29 16:11:12 -07003090 * We are bringing a node online. No memory is available yet. We must
Yasunori Gotob9049e22007-10-21 16:41:37 -07003091 * allocate a kmem_cache_node structure in order to bring the node
3092 * online.
3093 */
3094 down_read(&slub_lock);
3095 list_for_each_entry(s, &slab_caches, list) {
3096 /*
3097 * XXX: kmem_cache_alloc_node will fallback to other nodes
3098 * since memory is not yet available from the node that
3099 * is brought up.
3100 */
Christoph Lameter8de66a02010-08-25 14:51:14 -05003101 n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL);
Yasunori Gotob9049e22007-10-21 16:41:37 -07003102 if (!n) {
3103 ret = -ENOMEM;
3104 goto out;
3105 }
Pekka Enberg5595cff2008-08-05 09:28:47 +03003106 init_kmem_cache_node(n, s);
Yasunori Gotob9049e22007-10-21 16:41:37 -07003107 s->node[nid] = n;
3108 }
3109out:
3110 up_read(&slub_lock);
3111 return ret;
3112}
3113
3114static int slab_memory_callback(struct notifier_block *self,
3115 unsigned long action, void *arg)
3116{
3117 int ret = 0;
3118
3119 switch (action) {
3120 case MEM_GOING_ONLINE:
3121 ret = slab_mem_going_online_callback(arg);
3122 break;
3123 case MEM_GOING_OFFLINE:
3124 ret = slab_mem_going_offline_callback(arg);
3125 break;
3126 case MEM_OFFLINE:
3127 case MEM_CANCEL_ONLINE:
3128 slab_mem_offline_callback(arg);
3129 break;
3130 case MEM_ONLINE:
3131 case MEM_CANCEL_OFFLINE:
3132 break;
3133 }
KAMEZAWA Hiroyukidc19f9d2008-12-01 13:13:48 -08003134 if (ret)
3135 ret = notifier_from_errno(ret);
3136 else
3137 ret = NOTIFY_OK;
Yasunori Gotob9049e22007-10-21 16:41:37 -07003138 return ret;
3139}
3140
3141#endif /* CONFIG_MEMORY_HOTPLUG */
3142
Christoph Lameter81819f02007-05-06 14:49:36 -07003143/********************************************************************
3144 * Basic setup of slabs
3145 *******************************************************************/
3146
Christoph Lameter51df1142010-08-20 12:37:15 -05003147/*
3148 * Used for early kmem_cache structures that were allocated using
3149 * the page allocator
3150 */
3151
3152static void __init kmem_cache_bootstrap_fixup(struct kmem_cache *s)
3153{
3154 int node;
3155
3156 list_add(&s->list, &slab_caches);
3157 s->refcount = -1;
3158
3159 for_each_node_state(node, N_NORMAL_MEMORY) {
3160 struct kmem_cache_node *n = get_node(s, node);
3161 struct page *p;
3162
3163 if (n) {
3164 list_for_each_entry(p, &n->partial, lru)
3165 p->slab = s;
3166
Li Zefan607bf322011-04-12 15:22:26 +08003167#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter51df1142010-08-20 12:37:15 -05003168 list_for_each_entry(p, &n->full, lru)
3169 p->slab = s;
3170#endif
3171 }
3172 }
3173}
3174
Christoph Lameter81819f02007-05-06 14:49:36 -07003175void __init kmem_cache_init(void)
3176{
3177 int i;
Christoph Lameter4b356be2007-06-16 10:16:13 -07003178 int caches = 0;
Christoph Lameter51df1142010-08-20 12:37:15 -05003179 struct kmem_cache *temp_kmem_cache;
3180 int order;
Christoph Lameter51df1142010-08-20 12:37:15 -05003181 struct kmem_cache *temp_kmem_cache_node;
3182 unsigned long kmalloc_size;
3183
3184 kmem_size = offsetof(struct kmem_cache, node) +
3185 nr_node_ids * sizeof(struct kmem_cache_node *);
3186
3187 /* Allocate two kmem_caches from the page allocator */
3188 kmalloc_size = ALIGN(kmem_size, cache_line_size());
3189 order = get_order(2 * kmalloc_size);
3190 kmem_cache = (void *)__get_free_pages(GFP_NOWAIT, order);
3191
Christoph Lameter81819f02007-05-06 14:49:36 -07003192 /*
3193 * Must first have the slab cache available for the allocations of the
Christoph Lameter672bba32007-05-09 02:32:39 -07003194 * struct kmem_cache_node's. There is special bootstrap code in
Christoph Lameter81819f02007-05-06 14:49:36 -07003195 * kmem_cache_open for slab_state == DOWN.
3196 */
Christoph Lameter51df1142010-08-20 12:37:15 -05003197 kmem_cache_node = (void *)kmem_cache + kmalloc_size;
3198
3199 kmem_cache_open(kmem_cache_node, "kmem_cache_node",
3200 sizeof(struct kmem_cache_node),
3201 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
Yasunori Gotob9049e22007-10-21 16:41:37 -07003202
Nadia Derbey0c40ba42008-04-29 01:00:41 -07003203 hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI);
Christoph Lameter81819f02007-05-06 14:49:36 -07003204
3205 /* Able to allocate the per node structures */
3206 slab_state = PARTIAL;
3207
Christoph Lameter51df1142010-08-20 12:37:15 -05003208 temp_kmem_cache = kmem_cache;
3209 kmem_cache_open(kmem_cache, "kmem_cache", kmem_size,
3210 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
3211 kmem_cache = kmem_cache_alloc(kmem_cache, GFP_NOWAIT);
3212 memcpy(kmem_cache, temp_kmem_cache, kmem_size);
Christoph Lameter81819f02007-05-06 14:49:36 -07003213
Christoph Lameter51df1142010-08-20 12:37:15 -05003214 /*
3215 * Allocate kmem_cache_node properly from the kmem_cache slab.
3216 * kmem_cache_node is separately allocated so no need to
3217 * update any list pointers.
3218 */
3219 temp_kmem_cache_node = kmem_cache_node;
Christoph Lameter81819f02007-05-06 14:49:36 -07003220
Christoph Lameter51df1142010-08-20 12:37:15 -05003221 kmem_cache_node = kmem_cache_alloc(kmem_cache, GFP_NOWAIT);
3222 memcpy(kmem_cache_node, temp_kmem_cache_node, kmem_size);
3223
3224 kmem_cache_bootstrap_fixup(kmem_cache_node);
3225
3226 caches++;
Christoph Lameter51df1142010-08-20 12:37:15 -05003227 kmem_cache_bootstrap_fixup(kmem_cache);
3228 caches++;
3229 /* Free temporary boot structure */
3230 free_pages((unsigned long)temp_kmem_cache, order);
3231
3232 /* Now we can use the kmem_cache to allocate kmalloc slabs */
Christoph Lameterf1b26332007-07-17 04:03:26 -07003233
3234 /*
3235 * Patch up the size_index table if we have strange large alignment
3236 * requirements for the kmalloc array. This is only the case for
Christoph Lameter6446faa2008-02-15 23:45:26 -08003237 * MIPS it seems. The standard arches will not generate any code here.
Christoph Lameterf1b26332007-07-17 04:03:26 -07003238 *
3239 * Largest permitted alignment is 256 bytes due to the way we
3240 * handle the index determination for the smaller caches.
3241 *
3242 * Make sure that nothing crazy happens if someone starts tinkering
3243 * around with ARCH_KMALLOC_MINALIGN
3244 */
3245 BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 ||
3246 (KMALLOC_MIN_SIZE & (KMALLOC_MIN_SIZE - 1)));
3247
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003248 for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) {
3249 int elem = size_index_elem(i);
3250 if (elem >= ARRAY_SIZE(size_index))
3251 break;
3252 size_index[elem] = KMALLOC_SHIFT_LOW;
3253 }
Christoph Lameterf1b26332007-07-17 04:03:26 -07003254
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003255 if (KMALLOC_MIN_SIZE == 64) {
3256 /*
3257 * The 96 byte size cache is not used if the alignment
3258 * is 64 byte.
3259 */
3260 for (i = 64 + 8; i <= 96; i += 8)
3261 size_index[size_index_elem(i)] = 7;
3262 } else if (KMALLOC_MIN_SIZE == 128) {
Christoph Lameter41d54d32008-07-03 09:14:26 -05003263 /*
3264 * The 192 byte sized cache is not used if the alignment
3265 * is 128 byte. Redirect kmalloc to use the 256 byte cache
3266 * instead.
3267 */
3268 for (i = 128 + 8; i <= 192; i += 8)
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003269 size_index[size_index_elem(i)] = 8;
Christoph Lameter41d54d32008-07-03 09:14:26 -05003270 }
3271
Christoph Lameter51df1142010-08-20 12:37:15 -05003272 /* Caches that are not of the two-to-the-power-of size */
3273 if (KMALLOC_MIN_SIZE <= 32) {
3274 kmalloc_caches[1] = create_kmalloc_cache("kmalloc-96", 96, 0);
3275 caches++;
3276 }
3277
3278 if (KMALLOC_MIN_SIZE <= 64) {
3279 kmalloc_caches[2] = create_kmalloc_cache("kmalloc-192", 192, 0);
3280 caches++;
3281 }
3282
3283 for (i = KMALLOC_SHIFT_LOW; i < SLUB_PAGE_SHIFT; i++) {
3284 kmalloc_caches[i] = create_kmalloc_cache("kmalloc", 1 << i, 0);
3285 caches++;
3286 }
3287
Christoph Lameter81819f02007-05-06 14:49:36 -07003288 slab_state = UP;
3289
3290 /* Provide the correct kmalloc names now that the caches are up */
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003291 if (KMALLOC_MIN_SIZE <= 32) {
3292 kmalloc_caches[1]->name = kstrdup(kmalloc_caches[1]->name, GFP_NOWAIT);
3293 BUG_ON(!kmalloc_caches[1]->name);
3294 }
3295
3296 if (KMALLOC_MIN_SIZE <= 64) {
3297 kmalloc_caches[2]->name = kstrdup(kmalloc_caches[2]->name, GFP_NOWAIT);
3298 BUG_ON(!kmalloc_caches[2]->name);
3299 }
3300
Christoph Lameterd7278bd2010-07-09 14:07:12 -05003301 for (i = KMALLOC_SHIFT_LOW; i < SLUB_PAGE_SHIFT; i++) {
3302 char *s = kasprintf(GFP_NOWAIT, "kmalloc-%d", 1 << i);
3303
3304 BUG_ON(!s);
Christoph Lameter51df1142010-08-20 12:37:15 -05003305 kmalloc_caches[i]->name = s;
Christoph Lameterd7278bd2010-07-09 14:07:12 -05003306 }
Christoph Lameter81819f02007-05-06 14:49:36 -07003307
3308#ifdef CONFIG_SMP
3309 register_cpu_notifier(&slab_notifier);
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06003310#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07003311
Christoph Lameter55136592010-08-20 12:37:13 -05003312#ifdef CONFIG_ZONE_DMA
Christoph Lameter51df1142010-08-20 12:37:15 -05003313 for (i = 0; i < SLUB_PAGE_SHIFT; i++) {
3314 struct kmem_cache *s = kmalloc_caches[i];
Christoph Lameter55136592010-08-20 12:37:13 -05003315
Christoph Lameter51df1142010-08-20 12:37:15 -05003316 if (s && s->size) {
Christoph Lameter55136592010-08-20 12:37:13 -05003317 char *name = kasprintf(GFP_NOWAIT,
3318 "dma-kmalloc-%d", s->objsize);
3319
3320 BUG_ON(!name);
Christoph Lameter51df1142010-08-20 12:37:15 -05003321 kmalloc_dma_caches[i] = create_kmalloc_cache(name,
3322 s->objsize, SLAB_CACHE_DMA);
Christoph Lameter55136592010-08-20 12:37:13 -05003323 }
3324 }
3325#endif
Ingo Molnar3adbefe2008-02-05 17:57:39 -08003326 printk(KERN_INFO
3327 "SLUB: Genslabs=%d, HWalign=%d, Order=%d-%d, MinObjects=%d,"
Christoph Lameter4b356be2007-06-16 10:16:13 -07003328 " CPUs=%d, Nodes=%d\n",
3329 caches, cache_line_size(),
Christoph Lameter81819f02007-05-06 14:49:36 -07003330 slub_min_order, slub_max_order, slub_min_objects,
3331 nr_cpu_ids, nr_node_ids);
3332}
3333
Pekka Enberg7e85ee02009-06-12 14:03:06 +03003334void __init kmem_cache_init_late(void)
3335{
Pekka Enberg7e85ee02009-06-12 14:03:06 +03003336}
3337
Christoph Lameter81819f02007-05-06 14:49:36 -07003338/*
3339 * Find a mergeable slab cache
3340 */
3341static int slab_unmergeable(struct kmem_cache *s)
3342{
3343 if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE))
3344 return 1;
3345
Christoph Lameterc59def92007-05-16 22:10:50 -07003346 if (s->ctor)
Christoph Lameter81819f02007-05-06 14:49:36 -07003347 return 1;
3348
Christoph Lameter8ffa6872007-05-31 00:40:51 -07003349 /*
3350 * We may have set a slab to be unmergeable during bootstrap.
3351 */
3352 if (s->refcount < 0)
3353 return 1;
3354
Christoph Lameter81819f02007-05-06 14:49:36 -07003355 return 0;
3356}
3357
3358static struct kmem_cache *find_mergeable(size_t size,
Christoph Lameterba0268a2007-09-11 15:24:11 -07003359 size_t align, unsigned long flags, const char *name,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07003360 void (*ctor)(void *))
Christoph Lameter81819f02007-05-06 14:49:36 -07003361{
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07003362 struct kmem_cache *s;
Christoph Lameter81819f02007-05-06 14:49:36 -07003363
3364 if (slub_nomerge || (flags & SLUB_NEVER_MERGE))
3365 return NULL;
3366
Christoph Lameterc59def92007-05-16 22:10:50 -07003367 if (ctor)
Christoph Lameter81819f02007-05-06 14:49:36 -07003368 return NULL;
3369
3370 size = ALIGN(size, sizeof(void *));
3371 align = calculate_alignment(flags, align, size);
3372 size = ALIGN(size, align);
Christoph Lameterba0268a2007-09-11 15:24:11 -07003373 flags = kmem_cache_flags(size, flags, name, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -07003374
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07003375 list_for_each_entry(s, &slab_caches, list) {
Christoph Lameter81819f02007-05-06 14:49:36 -07003376 if (slab_unmergeable(s))
3377 continue;
3378
3379 if (size > s->size)
3380 continue;
3381
Christoph Lameterba0268a2007-09-11 15:24:11 -07003382 if ((flags & SLUB_MERGE_SAME) != (s->flags & SLUB_MERGE_SAME))
Christoph Lameter81819f02007-05-06 14:49:36 -07003383 continue;
3384 /*
3385 * Check if alignment is compatible.
3386 * Courtesy of Adrian Drzewiecki
3387 */
Pekka Enberg06428782008-01-07 23:20:27 -08003388 if ((s->size & ~(align - 1)) != s->size)
Christoph Lameter81819f02007-05-06 14:49:36 -07003389 continue;
3390
3391 if (s->size - size >= sizeof(void *))
3392 continue;
3393
3394 return s;
3395 }
3396 return NULL;
3397}
3398
3399struct kmem_cache *kmem_cache_create(const char *name, size_t size,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07003400 size_t align, unsigned long flags, void (*ctor)(void *))
Christoph Lameter81819f02007-05-06 14:49:36 -07003401{
3402 struct kmem_cache *s;
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003403 char *n;
Christoph Lameter81819f02007-05-06 14:49:36 -07003404
Benjamin Herrenschmidtfe1ff492009-09-21 17:02:30 -07003405 if (WARN_ON(!name))
3406 return NULL;
3407
Christoph Lameter81819f02007-05-06 14:49:36 -07003408 down_write(&slub_lock);
Christoph Lameterba0268a2007-09-11 15:24:11 -07003409 s = find_mergeable(size, align, flags, name, ctor);
Christoph Lameter81819f02007-05-06 14:49:36 -07003410 if (s) {
3411 s->refcount++;
3412 /*
3413 * Adjust the object sizes so that we clear
3414 * the complete object on kzalloc.
3415 */
3416 s->objsize = max(s->objsize, (int)size);
3417 s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *)));
Christoph Lameter6446faa2008-02-15 23:45:26 -08003418
David Rientjes7b8f3b62008-12-17 22:09:46 -08003419 if (sysfs_slab_alias(s, name)) {
David Rientjes7b8f3b62008-12-17 22:09:46 -08003420 s->refcount--;
Christoph Lameter81819f02007-05-06 14:49:36 -07003421 goto err;
David Rientjes7b8f3b62008-12-17 22:09:46 -08003422 }
Christoph Lameter2bce6482010-07-19 11:39:11 -05003423 up_write(&slub_lock);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003424 return s;
3425 }
Christoph Lameter6446faa2008-02-15 23:45:26 -08003426
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003427 n = kstrdup(name, GFP_KERNEL);
3428 if (!n)
3429 goto err;
3430
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003431 s = kmalloc(kmem_size, GFP_KERNEL);
3432 if (s) {
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003433 if (kmem_cache_open(s, n,
Christoph Lameterc59def92007-05-16 22:10:50 -07003434 size, align, flags, ctor)) {
Christoph Lameter81819f02007-05-06 14:49:36 -07003435 list_add(&s->list, &slab_caches);
David Rientjes7b8f3b62008-12-17 22:09:46 -08003436 if (sysfs_slab_add(s)) {
David Rientjes7b8f3b62008-12-17 22:09:46 -08003437 list_del(&s->list);
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003438 kfree(n);
David Rientjes7b8f3b62008-12-17 22:09:46 -08003439 kfree(s);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003440 goto err;
David Rientjes7b8f3b62008-12-17 22:09:46 -08003441 }
Christoph Lameter2bce6482010-07-19 11:39:11 -05003442 up_write(&slub_lock);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003443 return s;
3444 }
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003445 kfree(n);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003446 kfree(s);
Christoph Lameter81819f02007-05-06 14:49:36 -07003447 }
Pavel Emelyanov68cee4f12010-10-28 13:50:37 +04003448err:
Christoph Lameter81819f02007-05-06 14:49:36 -07003449 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07003450
Christoph Lameter81819f02007-05-06 14:49:36 -07003451 if (flags & SLAB_PANIC)
3452 panic("Cannot create slabcache %s\n", name);
3453 else
3454 s = NULL;
3455 return s;
3456}
3457EXPORT_SYMBOL(kmem_cache_create);
3458
Christoph Lameter81819f02007-05-06 14:49:36 -07003459#ifdef CONFIG_SMP
Christoph Lameter27390bc2007-06-01 00:47:09 -07003460/*
Christoph Lameter672bba32007-05-09 02:32:39 -07003461 * Use the cpu notifier to insure that the cpu slabs are flushed when
3462 * necessary.
Christoph Lameter81819f02007-05-06 14:49:36 -07003463 */
3464static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
3465 unsigned long action, void *hcpu)
3466{
3467 long cpu = (long)hcpu;
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07003468 struct kmem_cache *s;
3469 unsigned long flags;
Christoph Lameter81819f02007-05-06 14:49:36 -07003470
3471 switch (action) {
3472 case CPU_UP_CANCELED:
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07003473 case CPU_UP_CANCELED_FROZEN:
Christoph Lameter81819f02007-05-06 14:49:36 -07003474 case CPU_DEAD:
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07003475 case CPU_DEAD_FROZEN:
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07003476 down_read(&slub_lock);
3477 list_for_each_entry(s, &slab_caches, list) {
3478 local_irq_save(flags);
3479 __flush_cpu_slab(s, cpu);
3480 local_irq_restore(flags);
3481 }
3482 up_read(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07003483 break;
3484 default:
3485 break;
3486 }
3487 return NOTIFY_OK;
3488}
3489
Pekka Enberg06428782008-01-07 23:20:27 -08003490static struct notifier_block __cpuinitdata slab_notifier = {
Ingo Molnar3adbefe2008-02-05 17:57:39 -08003491 .notifier_call = slab_cpuup_callback
Pekka Enberg06428782008-01-07 23:20:27 -08003492};
Christoph Lameter81819f02007-05-06 14:49:36 -07003493
3494#endif
3495
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03003496void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, unsigned long caller)
Christoph Lameter81819f02007-05-06 14:49:36 -07003497{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003498 struct kmem_cache *s;
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003499 void *ret;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003500
Christoph Lameterffadd4d2009-02-17 12:05:07 -05003501 if (unlikely(size > SLUB_MAX_SIZE))
Pekka Enbergeada35e2008-02-11 22:47:46 +02003502 return kmalloc_large(size, gfpflags);
3503
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003504 s = get_slab(size, gfpflags);
Christoph Lameter81819f02007-05-06 14:49:36 -07003505
Satyam Sharma2408c552007-10-16 01:24:44 -07003506 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07003507 return s;
Christoph Lameter81819f02007-05-06 14:49:36 -07003508
Christoph Lameter2154a332010-07-09 14:07:10 -05003509 ret = slab_alloc(s, gfpflags, NUMA_NO_NODE, caller);
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003510
Lucas De Marchi25985ed2011-03-30 22:57:33 -03003511 /* Honor the call site pointer we received. */
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02003512 trace_kmalloc(caller, ret, size, s->size, gfpflags);
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003513
3514 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07003515}
3516
Namhyung Kim5d1f57e2010-09-29 21:02:15 +09003517#ifdef CONFIG_NUMA
Christoph Lameter81819f02007-05-06 14:49:36 -07003518void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03003519 int node, unsigned long caller)
Christoph Lameter81819f02007-05-06 14:49:36 -07003520{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003521 struct kmem_cache *s;
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003522 void *ret;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003523
Xiaotian Fengd3e14aa2010-04-08 17:26:44 +08003524 if (unlikely(size > SLUB_MAX_SIZE)) {
3525 ret = kmalloc_large_node(size, gfpflags, node);
3526
3527 trace_kmalloc_node(caller, ret,
3528 size, PAGE_SIZE << get_order(size),
3529 gfpflags, node);
3530
3531 return ret;
3532 }
Pekka Enbergeada35e2008-02-11 22:47:46 +02003533
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003534 s = get_slab(size, gfpflags);
Christoph Lameter81819f02007-05-06 14:49:36 -07003535
Satyam Sharma2408c552007-10-16 01:24:44 -07003536 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07003537 return s;
Christoph Lameter81819f02007-05-06 14:49:36 -07003538
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003539 ret = slab_alloc(s, gfpflags, node, caller);
3540
Lucas De Marchi25985ed2011-03-30 22:57:33 -03003541 /* Honor the call site pointer we received. */
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02003542 trace_kmalloc_node(caller, ret, size, s->size, gfpflags, node);
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003543
3544 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07003545}
Namhyung Kim5d1f57e2010-09-29 21:02:15 +09003546#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07003547
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05003548#ifdef CONFIG_SYSFS
Christoph Lameter205ab992008-04-14 19:11:40 +03003549static int count_inuse(struct page *page)
3550{
3551 return page->inuse;
3552}
3553
3554static int count_total(struct page *page)
3555{
3556 return page->objects;
3557}
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05003558#endif
Christoph Lameter205ab992008-04-14 19:11:40 +03003559
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05003560#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter434e2452007-07-17 04:03:30 -07003561static int validate_slab(struct kmem_cache *s, struct page *page,
3562 unsigned long *map)
Christoph Lameter53e15af2007-05-06 14:49:43 -07003563{
3564 void *p;
Christoph Lametera973e9d2008-03-01 13:40:44 -08003565 void *addr = page_address(page);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003566
3567 if (!check_slab(s, page) ||
3568 !on_freelist(s, page, NULL))
3569 return 0;
3570
3571 /* Now we know that a valid freelist exists */
Christoph Lameter39b26462008-04-14 19:11:30 +03003572 bitmap_zero(map, page->objects);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003573
Christoph Lameter5f80b132011-04-15 14:48:13 -05003574 get_map(s, page, map);
3575 for_each_object(p, s, addr, page->objects) {
3576 if (test_bit(slab_index(p, s, addr), map))
3577 if (!check_object(s, page, p, SLUB_RED_INACTIVE))
3578 return 0;
Christoph Lameter53e15af2007-05-06 14:49:43 -07003579 }
3580
Christoph Lameter224a88b2008-04-14 19:11:31 +03003581 for_each_object(p, s, addr, page->objects)
Christoph Lameter7656c722007-05-09 02:32:40 -07003582 if (!test_bit(slab_index(p, s, addr), map))
Tero Roponen37d57442010-12-01 20:04:20 +02003583 if (!check_object(s, page, p, SLUB_RED_ACTIVE))
Christoph Lameter53e15af2007-05-06 14:49:43 -07003584 return 0;
3585 return 1;
3586}
3587
Christoph Lameter434e2452007-07-17 04:03:30 -07003588static void validate_slab_slab(struct kmem_cache *s, struct page *page,
3589 unsigned long *map)
Christoph Lameter53e15af2007-05-06 14:49:43 -07003590{
3591 if (slab_trylock(page)) {
Christoph Lameter434e2452007-07-17 04:03:30 -07003592 validate_slab(s, page, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003593 slab_unlock(page);
3594 } else
3595 printk(KERN_INFO "SLUB %s: Skipped busy slab 0x%p\n",
3596 s->name, page);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003597}
3598
Christoph Lameter434e2452007-07-17 04:03:30 -07003599static int validate_slab_node(struct kmem_cache *s,
3600 struct kmem_cache_node *n, unsigned long *map)
Christoph Lameter53e15af2007-05-06 14:49:43 -07003601{
3602 unsigned long count = 0;
3603 struct page *page;
3604 unsigned long flags;
3605
3606 spin_lock_irqsave(&n->list_lock, flags);
3607
3608 list_for_each_entry(page, &n->partial, lru) {
Christoph Lameter434e2452007-07-17 04:03:30 -07003609 validate_slab_slab(s, page, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003610 count++;
3611 }
3612 if (count != n->nr_partial)
3613 printk(KERN_ERR "SLUB %s: %ld partial slabs counted but "
3614 "counter=%ld\n", s->name, count, n->nr_partial);
3615
3616 if (!(s->flags & SLAB_STORE_USER))
3617 goto out;
3618
3619 list_for_each_entry(page, &n->full, lru) {
Christoph Lameter434e2452007-07-17 04:03:30 -07003620 validate_slab_slab(s, page, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003621 count++;
3622 }
3623 if (count != atomic_long_read(&n->nr_slabs))
3624 printk(KERN_ERR "SLUB: %s %ld slabs counted but "
3625 "counter=%ld\n", s->name, count,
3626 atomic_long_read(&n->nr_slabs));
3627
3628out:
3629 spin_unlock_irqrestore(&n->list_lock, flags);
3630 return count;
3631}
3632
Christoph Lameter434e2452007-07-17 04:03:30 -07003633static long validate_slab_cache(struct kmem_cache *s)
Christoph Lameter53e15af2007-05-06 14:49:43 -07003634{
3635 int node;
3636 unsigned long count = 0;
Christoph Lameter205ab992008-04-14 19:11:40 +03003637 unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
Christoph Lameter434e2452007-07-17 04:03:30 -07003638 sizeof(unsigned long), GFP_KERNEL);
3639
3640 if (!map)
3641 return -ENOMEM;
Christoph Lameter53e15af2007-05-06 14:49:43 -07003642
3643 flush_all(s);
Christoph Lameterf64dc582007-10-16 01:25:33 -07003644 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter53e15af2007-05-06 14:49:43 -07003645 struct kmem_cache_node *n = get_node(s, node);
3646
Christoph Lameter434e2452007-07-17 04:03:30 -07003647 count += validate_slab_node(s, n, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003648 }
Christoph Lameter434e2452007-07-17 04:03:30 -07003649 kfree(map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003650 return count;
3651}
Christoph Lameter88a420e2007-05-06 14:49:45 -07003652/*
Christoph Lameter672bba32007-05-09 02:32:39 -07003653 * Generate lists of code addresses where slabcache objects are allocated
Christoph Lameter88a420e2007-05-06 14:49:45 -07003654 * and freed.
3655 */
3656
3657struct location {
3658 unsigned long count;
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03003659 unsigned long addr;
Christoph Lameter45edfa52007-05-09 02:32:45 -07003660 long long sum_time;
3661 long min_time;
3662 long max_time;
3663 long min_pid;
3664 long max_pid;
Rusty Russell174596a2009-01-01 10:12:29 +10303665 DECLARE_BITMAP(cpus, NR_CPUS);
Christoph Lameter45edfa52007-05-09 02:32:45 -07003666 nodemask_t nodes;
Christoph Lameter88a420e2007-05-06 14:49:45 -07003667};
3668
3669struct loc_track {
3670 unsigned long max;
3671 unsigned long count;
3672 struct location *loc;
3673};
3674
3675static void free_loc_track(struct loc_track *t)
3676{
3677 if (t->max)
3678 free_pages((unsigned long)t->loc,
3679 get_order(sizeof(struct location) * t->max));
3680}
3681
Christoph Lameter68dff6a2007-07-17 04:03:20 -07003682static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags)
Christoph Lameter88a420e2007-05-06 14:49:45 -07003683{
3684 struct location *l;
3685 int order;
3686
Christoph Lameter88a420e2007-05-06 14:49:45 -07003687 order = get_order(sizeof(struct location) * max);
3688
Christoph Lameter68dff6a2007-07-17 04:03:20 -07003689 l = (void *)__get_free_pages(flags, order);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003690 if (!l)
3691 return 0;
3692
3693 if (t->count) {
3694 memcpy(l, t->loc, sizeof(struct location) * t->count);
3695 free_loc_track(t);
3696 }
3697 t->max = max;
3698 t->loc = l;
3699 return 1;
3700}
3701
3702static int add_location(struct loc_track *t, struct kmem_cache *s,
Christoph Lameter45edfa52007-05-09 02:32:45 -07003703 const struct track *track)
Christoph Lameter88a420e2007-05-06 14:49:45 -07003704{
3705 long start, end, pos;
3706 struct location *l;
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03003707 unsigned long caddr;
Christoph Lameter45edfa52007-05-09 02:32:45 -07003708 unsigned long age = jiffies - track->when;
Christoph Lameter88a420e2007-05-06 14:49:45 -07003709
3710 start = -1;
3711 end = t->count;
3712
3713 for ( ; ; ) {
3714 pos = start + (end - start + 1) / 2;
3715
3716 /*
3717 * There is nothing at "end". If we end up there
3718 * we need to add something to before end.
3719 */
3720 if (pos == end)
3721 break;
3722
3723 caddr = t->loc[pos].addr;
Christoph Lameter45edfa52007-05-09 02:32:45 -07003724 if (track->addr == caddr) {
3725
3726 l = &t->loc[pos];
3727 l->count++;
3728 if (track->when) {
3729 l->sum_time += age;
3730 if (age < l->min_time)
3731 l->min_time = age;
3732 if (age > l->max_time)
3733 l->max_time = age;
3734
3735 if (track->pid < l->min_pid)
3736 l->min_pid = track->pid;
3737 if (track->pid > l->max_pid)
3738 l->max_pid = track->pid;
3739
Rusty Russell174596a2009-01-01 10:12:29 +10303740 cpumask_set_cpu(track->cpu,
3741 to_cpumask(l->cpus));
Christoph Lameter45edfa52007-05-09 02:32:45 -07003742 }
3743 node_set(page_to_nid(virt_to_page(track)), l->nodes);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003744 return 1;
3745 }
3746
Christoph Lameter45edfa52007-05-09 02:32:45 -07003747 if (track->addr < caddr)
Christoph Lameter88a420e2007-05-06 14:49:45 -07003748 end = pos;
3749 else
3750 start = pos;
3751 }
3752
3753 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07003754 * Not found. Insert new tracking element.
Christoph Lameter88a420e2007-05-06 14:49:45 -07003755 */
Christoph Lameter68dff6a2007-07-17 04:03:20 -07003756 if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC))
Christoph Lameter88a420e2007-05-06 14:49:45 -07003757 return 0;
3758
3759 l = t->loc + pos;
3760 if (pos < t->count)
3761 memmove(l + 1, l,
3762 (t->count - pos) * sizeof(struct location));
3763 t->count++;
3764 l->count = 1;
Christoph Lameter45edfa52007-05-09 02:32:45 -07003765 l->addr = track->addr;
3766 l->sum_time = age;
3767 l->min_time = age;
3768 l->max_time = age;
3769 l->min_pid = track->pid;
3770 l->max_pid = track->pid;
Rusty Russell174596a2009-01-01 10:12:29 +10303771 cpumask_clear(to_cpumask(l->cpus));
3772 cpumask_set_cpu(track->cpu, to_cpumask(l->cpus));
Christoph Lameter45edfa52007-05-09 02:32:45 -07003773 nodes_clear(l->nodes);
3774 node_set(page_to_nid(virt_to_page(track)), l->nodes);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003775 return 1;
3776}
3777
3778static void process_slab(struct loc_track *t, struct kmem_cache *s,
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003779 struct page *page, enum track_item alloc,
Namhyung Kima5dd5c12010-09-29 21:02:13 +09003780 unsigned long *map)
Christoph Lameter88a420e2007-05-06 14:49:45 -07003781{
Christoph Lametera973e9d2008-03-01 13:40:44 -08003782 void *addr = page_address(page);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003783 void *p;
3784
Christoph Lameter39b26462008-04-14 19:11:30 +03003785 bitmap_zero(map, page->objects);
Christoph Lameter5f80b132011-04-15 14:48:13 -05003786 get_map(s, page, map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003787
Christoph Lameter224a88b2008-04-14 19:11:31 +03003788 for_each_object(p, s, addr, page->objects)
Christoph Lameter45edfa52007-05-09 02:32:45 -07003789 if (!test_bit(slab_index(p, s, addr), map))
3790 add_location(t, s, get_track(s, p, alloc));
Christoph Lameter88a420e2007-05-06 14:49:45 -07003791}
3792
3793static int list_locations(struct kmem_cache *s, char *buf,
3794 enum track_item alloc)
3795{
Harvey Harrisone374d482008-01-31 15:20:50 -08003796 int len = 0;
Christoph Lameter88a420e2007-05-06 14:49:45 -07003797 unsigned long i;
Christoph Lameter68dff6a2007-07-17 04:03:20 -07003798 struct loc_track t = { 0, 0, NULL };
Christoph Lameter88a420e2007-05-06 14:49:45 -07003799 int node;
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003800 unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
3801 sizeof(unsigned long), GFP_KERNEL);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003802
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003803 if (!map || !alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location),
3804 GFP_TEMPORARY)) {
3805 kfree(map);
Christoph Lameter68dff6a2007-07-17 04:03:20 -07003806 return sprintf(buf, "Out of memory\n");
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003807 }
Christoph Lameter88a420e2007-05-06 14:49:45 -07003808 /* Push back cpu slabs */
3809 flush_all(s);
3810
Christoph Lameterf64dc582007-10-16 01:25:33 -07003811 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter88a420e2007-05-06 14:49:45 -07003812 struct kmem_cache_node *n = get_node(s, node);
3813 unsigned long flags;
3814 struct page *page;
3815
Christoph Lameter9e869432007-08-22 14:01:56 -07003816 if (!atomic_long_read(&n->nr_slabs))
Christoph Lameter88a420e2007-05-06 14:49:45 -07003817 continue;
3818
3819 spin_lock_irqsave(&n->list_lock, flags);
3820 list_for_each_entry(page, &n->partial, lru)
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003821 process_slab(&t, s, page, alloc, map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003822 list_for_each_entry(page, &n->full, lru)
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003823 process_slab(&t, s, page, alloc, map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003824 spin_unlock_irqrestore(&n->list_lock, flags);
3825 }
3826
3827 for (i = 0; i < t.count; i++) {
Christoph Lameter45edfa52007-05-09 02:32:45 -07003828 struct location *l = &t.loc[i];
Christoph Lameter88a420e2007-05-06 14:49:45 -07003829
Hugh Dickins9c246242008-12-09 13:14:27 -08003830 if (len > PAGE_SIZE - KSYM_SYMBOL_LEN - 100)
Christoph Lameter88a420e2007-05-06 14:49:45 -07003831 break;
Harvey Harrisone374d482008-01-31 15:20:50 -08003832 len += sprintf(buf + len, "%7ld ", l->count);
Christoph Lameter45edfa52007-05-09 02:32:45 -07003833
3834 if (l->addr)
Joe Perches62c70bc2011-01-13 15:45:52 -08003835 len += sprintf(buf + len, "%pS", (void *)l->addr);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003836 else
Harvey Harrisone374d482008-01-31 15:20:50 -08003837 len += sprintf(buf + len, "<not-available>");
Christoph Lameter45edfa52007-05-09 02:32:45 -07003838
3839 if (l->sum_time != l->min_time) {
Harvey Harrisone374d482008-01-31 15:20:50 -08003840 len += sprintf(buf + len, " age=%ld/%ld/%ld",
Roman Zippelf8bd2252008-05-01 04:34:31 -07003841 l->min_time,
3842 (long)div_u64(l->sum_time, l->count),
3843 l->max_time);
Christoph Lameter45edfa52007-05-09 02:32:45 -07003844 } else
Harvey Harrisone374d482008-01-31 15:20:50 -08003845 len += sprintf(buf + len, " age=%ld",
Christoph Lameter45edfa52007-05-09 02:32:45 -07003846 l->min_time);
3847
3848 if (l->min_pid != l->max_pid)
Harvey Harrisone374d482008-01-31 15:20:50 -08003849 len += sprintf(buf + len, " pid=%ld-%ld",
Christoph Lameter45edfa52007-05-09 02:32:45 -07003850 l->min_pid, l->max_pid);
3851 else
Harvey Harrisone374d482008-01-31 15:20:50 -08003852 len += sprintf(buf + len, " pid=%ld",
Christoph Lameter45edfa52007-05-09 02:32:45 -07003853 l->min_pid);
3854
Rusty Russell174596a2009-01-01 10:12:29 +10303855 if (num_online_cpus() > 1 &&
3856 !cpumask_empty(to_cpumask(l->cpus)) &&
Harvey Harrisone374d482008-01-31 15:20:50 -08003857 len < PAGE_SIZE - 60) {
3858 len += sprintf(buf + len, " cpus=");
3859 len += cpulist_scnprintf(buf + len, PAGE_SIZE - len - 50,
Rusty Russell174596a2009-01-01 10:12:29 +10303860 to_cpumask(l->cpus));
Christoph Lameter45edfa52007-05-09 02:32:45 -07003861 }
3862
Christoph Lameter62bc62a2009-06-16 15:32:15 -07003863 if (nr_online_nodes > 1 && !nodes_empty(l->nodes) &&
Harvey Harrisone374d482008-01-31 15:20:50 -08003864 len < PAGE_SIZE - 60) {
3865 len += sprintf(buf + len, " nodes=");
3866 len += nodelist_scnprintf(buf + len, PAGE_SIZE - len - 50,
Christoph Lameter45edfa52007-05-09 02:32:45 -07003867 l->nodes);
3868 }
3869
Harvey Harrisone374d482008-01-31 15:20:50 -08003870 len += sprintf(buf + len, "\n");
Christoph Lameter88a420e2007-05-06 14:49:45 -07003871 }
3872
3873 free_loc_track(&t);
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003874 kfree(map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003875 if (!t.count)
Harvey Harrisone374d482008-01-31 15:20:50 -08003876 len += sprintf(buf, "No data\n");
3877 return len;
Christoph Lameter88a420e2007-05-06 14:49:45 -07003878}
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05003879#endif
Christoph Lameter88a420e2007-05-06 14:49:45 -07003880
Christoph Lametera5a84752010-10-05 13:57:27 -05003881#ifdef SLUB_RESILIENCY_TEST
3882static void resiliency_test(void)
3883{
3884 u8 *p;
3885
3886 BUILD_BUG_ON(KMALLOC_MIN_SIZE > 16 || SLUB_PAGE_SHIFT < 10);
3887
3888 printk(KERN_ERR "SLUB resiliency testing\n");
3889 printk(KERN_ERR "-----------------------\n");
3890 printk(KERN_ERR "A. Corruption after allocation\n");
3891
3892 p = kzalloc(16, GFP_KERNEL);
3893 p[16] = 0x12;
3894 printk(KERN_ERR "\n1. kmalloc-16: Clobber Redzone/next pointer"
3895 " 0x12->0x%p\n\n", p + 16);
3896
3897 validate_slab_cache(kmalloc_caches[4]);
3898
3899 /* Hmmm... The next two are dangerous */
3900 p = kzalloc(32, GFP_KERNEL);
3901 p[32 + sizeof(void *)] = 0x34;
3902 printk(KERN_ERR "\n2. kmalloc-32: Clobber next pointer/next slab"
3903 " 0x34 -> -0x%p\n", p);
3904 printk(KERN_ERR
3905 "If allocated object is overwritten then not detectable\n\n");
3906
3907 validate_slab_cache(kmalloc_caches[5]);
3908 p = kzalloc(64, GFP_KERNEL);
3909 p += 64 + (get_cycles() & 0xff) * sizeof(void *);
3910 *p = 0x56;
3911 printk(KERN_ERR "\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n",
3912 p);
3913 printk(KERN_ERR
3914 "If allocated object is overwritten then not detectable\n\n");
3915 validate_slab_cache(kmalloc_caches[6]);
3916
3917 printk(KERN_ERR "\nB. Corruption after free\n");
3918 p = kzalloc(128, GFP_KERNEL);
3919 kfree(p);
3920 *p = 0x78;
3921 printk(KERN_ERR "1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p);
3922 validate_slab_cache(kmalloc_caches[7]);
3923
3924 p = kzalloc(256, GFP_KERNEL);
3925 kfree(p);
3926 p[50] = 0x9a;
3927 printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n",
3928 p);
3929 validate_slab_cache(kmalloc_caches[8]);
3930
3931 p = kzalloc(512, GFP_KERNEL);
3932 kfree(p);
3933 p[512] = 0xab;
3934 printk(KERN_ERR "\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p);
3935 validate_slab_cache(kmalloc_caches[9]);
3936}
3937#else
3938#ifdef CONFIG_SYSFS
3939static void resiliency_test(void) {};
3940#endif
3941#endif
3942
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05003943#ifdef CONFIG_SYSFS
Christoph Lameter81819f02007-05-06 14:49:36 -07003944enum slab_stat_type {
Christoph Lameter205ab992008-04-14 19:11:40 +03003945 SL_ALL, /* All slabs */
3946 SL_PARTIAL, /* Only partially allocated slabs */
3947 SL_CPU, /* Only slabs used for cpu caches */
3948 SL_OBJECTS, /* Determine allocated objects not slabs */
3949 SL_TOTAL /* Determine object capacity not slabs */
Christoph Lameter81819f02007-05-06 14:49:36 -07003950};
3951
Christoph Lameter205ab992008-04-14 19:11:40 +03003952#define SO_ALL (1 << SL_ALL)
Christoph Lameter81819f02007-05-06 14:49:36 -07003953#define SO_PARTIAL (1 << SL_PARTIAL)
3954#define SO_CPU (1 << SL_CPU)
3955#define SO_OBJECTS (1 << SL_OBJECTS)
Christoph Lameter205ab992008-04-14 19:11:40 +03003956#define SO_TOTAL (1 << SL_TOTAL)
Christoph Lameter81819f02007-05-06 14:49:36 -07003957
Cyrill Gorcunov62e5c4b2008-03-02 23:28:24 +03003958static ssize_t show_slab_objects(struct kmem_cache *s,
3959 char *buf, unsigned long flags)
Christoph Lameter81819f02007-05-06 14:49:36 -07003960{
3961 unsigned long total = 0;
Christoph Lameter81819f02007-05-06 14:49:36 -07003962 int node;
3963 int x;
3964 unsigned long *nodes;
3965 unsigned long *per_cpu;
3966
3967 nodes = kzalloc(2 * sizeof(unsigned long) * nr_node_ids, GFP_KERNEL);
Cyrill Gorcunov62e5c4b2008-03-02 23:28:24 +03003968 if (!nodes)
3969 return -ENOMEM;
Christoph Lameter81819f02007-05-06 14:49:36 -07003970 per_cpu = nodes + nr_node_ids;
3971
Christoph Lameter205ab992008-04-14 19:11:40 +03003972 if (flags & SO_CPU) {
3973 int cpu;
Christoph Lameter81819f02007-05-06 14:49:36 -07003974
Christoph Lameter205ab992008-04-14 19:11:40 +03003975 for_each_possible_cpu(cpu) {
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06003976 struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
Christoph Lameterdfb4f092007-10-16 01:26:05 -07003977
Christoph Lameter205ab992008-04-14 19:11:40 +03003978 if (!c || c->node < 0)
3979 continue;
3980
3981 if (c->page) {
3982 if (flags & SO_TOTAL)
3983 x = c->page->objects;
3984 else if (flags & SO_OBJECTS)
3985 x = c->page->inuse;
Christoph Lameter81819f02007-05-06 14:49:36 -07003986 else
3987 x = 1;
Christoph Lameter205ab992008-04-14 19:11:40 +03003988
Christoph Lameter81819f02007-05-06 14:49:36 -07003989 total += x;
Christoph Lameter205ab992008-04-14 19:11:40 +03003990 nodes[c->node] += x;
Christoph Lameter81819f02007-05-06 14:49:36 -07003991 }
Christoph Lameter205ab992008-04-14 19:11:40 +03003992 per_cpu[c->node]++;
Christoph Lameter81819f02007-05-06 14:49:36 -07003993 }
3994 }
3995
Christoph Lameter04d94872011-01-10 10:15:15 -06003996 lock_memory_hotplug();
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05003997#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter205ab992008-04-14 19:11:40 +03003998 if (flags & SO_ALL) {
3999 for_each_node_state(node, N_NORMAL_MEMORY) {
4000 struct kmem_cache_node *n = get_node(s, node);
Christoph Lameter81819f02007-05-06 14:49:36 -07004001
Christoph Lameter205ab992008-04-14 19:11:40 +03004002 if (flags & SO_TOTAL)
4003 x = atomic_long_read(&n->total_objects);
4004 else if (flags & SO_OBJECTS)
4005 x = atomic_long_read(&n->total_objects) -
4006 count_partial(n, count_free);
4007
4008 else
4009 x = atomic_long_read(&n->nr_slabs);
4010 total += x;
4011 nodes[node] += x;
4012 }
4013
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004014 } else
4015#endif
4016 if (flags & SO_PARTIAL) {
Christoph Lameter205ab992008-04-14 19:11:40 +03004017 for_each_node_state(node, N_NORMAL_MEMORY) {
4018 struct kmem_cache_node *n = get_node(s, node);
4019
4020 if (flags & SO_TOTAL)
4021 x = count_partial(n, count_total);
4022 else if (flags & SO_OBJECTS)
4023 x = count_partial(n, count_inuse);
Christoph Lameter81819f02007-05-06 14:49:36 -07004024 else
4025 x = n->nr_partial;
4026 total += x;
4027 nodes[node] += x;
4028 }
Christoph Lameter81819f02007-05-06 14:49:36 -07004029 }
Christoph Lameter81819f02007-05-06 14:49:36 -07004030 x = sprintf(buf, "%lu", total);
4031#ifdef CONFIG_NUMA
Christoph Lameterf64dc582007-10-16 01:25:33 -07004032 for_each_node_state(node, N_NORMAL_MEMORY)
Christoph Lameter81819f02007-05-06 14:49:36 -07004033 if (nodes[node])
4034 x += sprintf(buf + x, " N%d=%lu",
4035 node, nodes[node]);
4036#endif
Christoph Lameter04d94872011-01-10 10:15:15 -06004037 unlock_memory_hotplug();
Christoph Lameter81819f02007-05-06 14:49:36 -07004038 kfree(nodes);
4039 return x + sprintf(buf + x, "\n");
4040}
4041
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004042#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter81819f02007-05-06 14:49:36 -07004043static int any_slab_objects(struct kmem_cache *s)
4044{
4045 int node;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07004046
4047 for_each_online_node(node) {
Christoph Lameter81819f02007-05-06 14:49:36 -07004048 struct kmem_cache_node *n = get_node(s, node);
4049
Christoph Lameterdfb4f092007-10-16 01:26:05 -07004050 if (!n)
4051 continue;
4052
Benjamin Herrenschmidt4ea33e22008-05-06 20:42:39 -07004053 if (atomic_long_read(&n->total_objects))
Christoph Lameter81819f02007-05-06 14:49:36 -07004054 return 1;
4055 }
4056 return 0;
4057}
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004058#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07004059
4060#define to_slab_attr(n) container_of(n, struct slab_attribute, attr)
4061#define to_slab(n) container_of(n, struct kmem_cache, kobj);
4062
4063struct slab_attribute {
4064 struct attribute attr;
4065 ssize_t (*show)(struct kmem_cache *s, char *buf);
4066 ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count);
4067};
4068
4069#define SLAB_ATTR_RO(_name) \
4070 static struct slab_attribute _name##_attr = __ATTR_RO(_name)
4071
4072#define SLAB_ATTR(_name) \
4073 static struct slab_attribute _name##_attr = \
4074 __ATTR(_name, 0644, _name##_show, _name##_store)
4075
Christoph Lameter81819f02007-05-06 14:49:36 -07004076static ssize_t slab_size_show(struct kmem_cache *s, char *buf)
4077{
4078 return sprintf(buf, "%d\n", s->size);
4079}
4080SLAB_ATTR_RO(slab_size);
4081
4082static ssize_t align_show(struct kmem_cache *s, char *buf)
4083{
4084 return sprintf(buf, "%d\n", s->align);
4085}
4086SLAB_ATTR_RO(align);
4087
4088static ssize_t object_size_show(struct kmem_cache *s, char *buf)
4089{
4090 return sprintf(buf, "%d\n", s->objsize);
4091}
4092SLAB_ATTR_RO(object_size);
4093
4094static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf)
4095{
Christoph Lameter834f3d12008-04-14 19:11:31 +03004096 return sprintf(buf, "%d\n", oo_objects(s->oo));
Christoph Lameter81819f02007-05-06 14:49:36 -07004097}
4098SLAB_ATTR_RO(objs_per_slab);
4099
Christoph Lameter06b285d2008-04-14 19:11:41 +03004100static ssize_t order_store(struct kmem_cache *s,
4101 const char *buf, size_t length)
4102{
Christoph Lameter0121c6192008-04-29 16:11:12 -07004103 unsigned long order;
4104 int err;
4105
4106 err = strict_strtoul(buf, 10, &order);
4107 if (err)
4108 return err;
Christoph Lameter06b285d2008-04-14 19:11:41 +03004109
4110 if (order > slub_max_order || order < slub_min_order)
4111 return -EINVAL;
4112
4113 calculate_sizes(s, order);
4114 return length;
4115}
4116
Christoph Lameter81819f02007-05-06 14:49:36 -07004117static ssize_t order_show(struct kmem_cache *s, char *buf)
4118{
Christoph Lameter834f3d12008-04-14 19:11:31 +03004119 return sprintf(buf, "%d\n", oo_order(s->oo));
Christoph Lameter81819f02007-05-06 14:49:36 -07004120}
Christoph Lameter06b285d2008-04-14 19:11:41 +03004121SLAB_ATTR(order);
Christoph Lameter81819f02007-05-06 14:49:36 -07004122
David Rientjes73d342b2009-02-22 17:40:09 -08004123static ssize_t min_partial_show(struct kmem_cache *s, char *buf)
4124{
4125 return sprintf(buf, "%lu\n", s->min_partial);
4126}
4127
4128static ssize_t min_partial_store(struct kmem_cache *s, const char *buf,
4129 size_t length)
4130{
4131 unsigned long min;
4132 int err;
4133
4134 err = strict_strtoul(buf, 10, &min);
4135 if (err)
4136 return err;
4137
David Rientjesc0bdb232009-02-25 09:16:35 +02004138 set_min_partial(s, min);
David Rientjes73d342b2009-02-22 17:40:09 -08004139 return length;
4140}
4141SLAB_ATTR(min_partial);
4142
Christoph Lameter81819f02007-05-06 14:49:36 -07004143static ssize_t ctor_show(struct kmem_cache *s, char *buf)
4144{
Joe Perches62c70bc2011-01-13 15:45:52 -08004145 if (!s->ctor)
4146 return 0;
4147 return sprintf(buf, "%pS\n", s->ctor);
Christoph Lameter81819f02007-05-06 14:49:36 -07004148}
4149SLAB_ATTR_RO(ctor);
4150
Christoph Lameter81819f02007-05-06 14:49:36 -07004151static ssize_t aliases_show(struct kmem_cache *s, char *buf)
4152{
4153 return sprintf(buf, "%d\n", s->refcount - 1);
4154}
4155SLAB_ATTR_RO(aliases);
4156
Christoph Lameter81819f02007-05-06 14:49:36 -07004157static ssize_t partial_show(struct kmem_cache *s, char *buf)
4158{
Christoph Lameterd9acf4b2008-02-15 15:22:21 -08004159 return show_slab_objects(s, buf, SO_PARTIAL);
Christoph Lameter81819f02007-05-06 14:49:36 -07004160}
4161SLAB_ATTR_RO(partial);
4162
4163static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf)
4164{
Christoph Lameterd9acf4b2008-02-15 15:22:21 -08004165 return show_slab_objects(s, buf, SO_CPU);
Christoph Lameter81819f02007-05-06 14:49:36 -07004166}
4167SLAB_ATTR_RO(cpu_slabs);
4168
4169static ssize_t objects_show(struct kmem_cache *s, char *buf)
4170{
Christoph Lameter205ab992008-04-14 19:11:40 +03004171 return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS);
Christoph Lameter81819f02007-05-06 14:49:36 -07004172}
4173SLAB_ATTR_RO(objects);
4174
Christoph Lameter205ab992008-04-14 19:11:40 +03004175static ssize_t objects_partial_show(struct kmem_cache *s, char *buf)
4176{
4177 return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS);
4178}
4179SLAB_ATTR_RO(objects_partial);
4180
Christoph Lameter81819f02007-05-06 14:49:36 -07004181static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf)
4182{
4183 return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT));
4184}
4185
4186static ssize_t reclaim_account_store(struct kmem_cache *s,
4187 const char *buf, size_t length)
4188{
4189 s->flags &= ~SLAB_RECLAIM_ACCOUNT;
4190 if (buf[0] == '1')
4191 s->flags |= SLAB_RECLAIM_ACCOUNT;
4192 return length;
4193}
4194SLAB_ATTR(reclaim_account);
4195
4196static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf)
4197{
Christoph Lameter5af60832007-05-06 14:49:56 -07004198 return sprintf(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN));
Christoph Lameter81819f02007-05-06 14:49:36 -07004199}
4200SLAB_ATTR_RO(hwcache_align);
4201
4202#ifdef CONFIG_ZONE_DMA
4203static ssize_t cache_dma_show(struct kmem_cache *s, char *buf)
4204{
4205 return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA));
4206}
4207SLAB_ATTR_RO(cache_dma);
4208#endif
4209
4210static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf)
4211{
4212 return sprintf(buf, "%d\n", !!(s->flags & SLAB_DESTROY_BY_RCU));
4213}
4214SLAB_ATTR_RO(destroy_by_rcu);
4215
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08004216static ssize_t reserved_show(struct kmem_cache *s, char *buf)
4217{
4218 return sprintf(buf, "%d\n", s->reserved);
4219}
4220SLAB_ATTR_RO(reserved);
4221
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004222#ifdef CONFIG_SLUB_DEBUG
Christoph Lametera5a84752010-10-05 13:57:27 -05004223static ssize_t slabs_show(struct kmem_cache *s, char *buf)
4224{
4225 return show_slab_objects(s, buf, SO_ALL);
4226}
4227SLAB_ATTR_RO(slabs);
4228
4229static ssize_t total_objects_show(struct kmem_cache *s, char *buf)
4230{
4231 return show_slab_objects(s, buf, SO_ALL|SO_TOTAL);
4232}
4233SLAB_ATTR_RO(total_objects);
4234
4235static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf)
4236{
4237 return sprintf(buf, "%d\n", !!(s->flags & SLAB_DEBUG_FREE));
4238}
4239
4240static ssize_t sanity_checks_store(struct kmem_cache *s,
4241 const char *buf, size_t length)
4242{
4243 s->flags &= ~SLAB_DEBUG_FREE;
4244 if (buf[0] == '1')
4245 s->flags |= SLAB_DEBUG_FREE;
4246 return length;
4247}
4248SLAB_ATTR(sanity_checks);
4249
4250static ssize_t trace_show(struct kmem_cache *s, char *buf)
4251{
4252 return sprintf(buf, "%d\n", !!(s->flags & SLAB_TRACE));
4253}
4254
4255static ssize_t trace_store(struct kmem_cache *s, const char *buf,
4256 size_t length)
4257{
4258 s->flags &= ~SLAB_TRACE;
4259 if (buf[0] == '1')
4260 s->flags |= SLAB_TRACE;
4261 return length;
4262}
4263SLAB_ATTR(trace);
4264
Christoph Lameter81819f02007-05-06 14:49:36 -07004265static ssize_t red_zone_show(struct kmem_cache *s, char *buf)
4266{
4267 return sprintf(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE));
4268}
4269
4270static ssize_t red_zone_store(struct kmem_cache *s,
4271 const char *buf, size_t length)
4272{
4273 if (any_slab_objects(s))
4274 return -EBUSY;
4275
4276 s->flags &= ~SLAB_RED_ZONE;
4277 if (buf[0] == '1')
4278 s->flags |= SLAB_RED_ZONE;
Christoph Lameter06b285d2008-04-14 19:11:41 +03004279 calculate_sizes(s, -1);
Christoph Lameter81819f02007-05-06 14:49:36 -07004280 return length;
4281}
4282SLAB_ATTR(red_zone);
4283
4284static ssize_t poison_show(struct kmem_cache *s, char *buf)
4285{
4286 return sprintf(buf, "%d\n", !!(s->flags & SLAB_POISON));
4287}
4288
4289static ssize_t poison_store(struct kmem_cache *s,
4290 const char *buf, size_t length)
4291{
4292 if (any_slab_objects(s))
4293 return -EBUSY;
4294
4295 s->flags &= ~SLAB_POISON;
4296 if (buf[0] == '1')
4297 s->flags |= SLAB_POISON;
Christoph Lameter06b285d2008-04-14 19:11:41 +03004298 calculate_sizes(s, -1);
Christoph Lameter81819f02007-05-06 14:49:36 -07004299 return length;
4300}
4301SLAB_ATTR(poison);
4302
4303static ssize_t store_user_show(struct kmem_cache *s, char *buf)
4304{
4305 return sprintf(buf, "%d\n", !!(s->flags & SLAB_STORE_USER));
4306}
4307
4308static ssize_t store_user_store(struct kmem_cache *s,
4309 const char *buf, size_t length)
4310{
4311 if (any_slab_objects(s))
4312 return -EBUSY;
4313
4314 s->flags &= ~SLAB_STORE_USER;
4315 if (buf[0] == '1')
4316 s->flags |= SLAB_STORE_USER;
Christoph Lameter06b285d2008-04-14 19:11:41 +03004317 calculate_sizes(s, -1);
Christoph Lameter81819f02007-05-06 14:49:36 -07004318 return length;
4319}
4320SLAB_ATTR(store_user);
4321
Christoph Lameter53e15af2007-05-06 14:49:43 -07004322static ssize_t validate_show(struct kmem_cache *s, char *buf)
4323{
4324 return 0;
4325}
4326
4327static ssize_t validate_store(struct kmem_cache *s,
4328 const char *buf, size_t length)
4329{
Christoph Lameter434e2452007-07-17 04:03:30 -07004330 int ret = -EINVAL;
4331
4332 if (buf[0] == '1') {
4333 ret = validate_slab_cache(s);
4334 if (ret >= 0)
4335 ret = length;
4336 }
4337 return ret;
Christoph Lameter53e15af2007-05-06 14:49:43 -07004338}
4339SLAB_ATTR(validate);
Christoph Lametera5a84752010-10-05 13:57:27 -05004340
4341static ssize_t alloc_calls_show(struct kmem_cache *s, char *buf)
4342{
4343 if (!(s->flags & SLAB_STORE_USER))
4344 return -ENOSYS;
4345 return list_locations(s, buf, TRACK_ALLOC);
4346}
4347SLAB_ATTR_RO(alloc_calls);
4348
4349static ssize_t free_calls_show(struct kmem_cache *s, char *buf)
4350{
4351 if (!(s->flags & SLAB_STORE_USER))
4352 return -ENOSYS;
4353 return list_locations(s, buf, TRACK_FREE);
4354}
4355SLAB_ATTR_RO(free_calls);
4356#endif /* CONFIG_SLUB_DEBUG */
4357
4358#ifdef CONFIG_FAILSLAB
4359static ssize_t failslab_show(struct kmem_cache *s, char *buf)
4360{
4361 return sprintf(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB));
4362}
4363
4364static ssize_t failslab_store(struct kmem_cache *s, const char *buf,
4365 size_t length)
4366{
4367 s->flags &= ~SLAB_FAILSLAB;
4368 if (buf[0] == '1')
4369 s->flags |= SLAB_FAILSLAB;
4370 return length;
4371}
4372SLAB_ATTR(failslab);
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004373#endif
Christoph Lameter53e15af2007-05-06 14:49:43 -07004374
Christoph Lameter2086d262007-05-06 14:49:46 -07004375static ssize_t shrink_show(struct kmem_cache *s, char *buf)
4376{
4377 return 0;
4378}
4379
4380static ssize_t shrink_store(struct kmem_cache *s,
4381 const char *buf, size_t length)
4382{
4383 if (buf[0] == '1') {
4384 int rc = kmem_cache_shrink(s);
4385
4386 if (rc)
4387 return rc;
4388 } else
4389 return -EINVAL;
4390 return length;
4391}
4392SLAB_ATTR(shrink);
4393
Christoph Lameter81819f02007-05-06 14:49:36 -07004394#ifdef CONFIG_NUMA
Christoph Lameter98246012008-01-07 23:20:26 -08004395static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf)
Christoph Lameter81819f02007-05-06 14:49:36 -07004396{
Christoph Lameter98246012008-01-07 23:20:26 -08004397 return sprintf(buf, "%d\n", s->remote_node_defrag_ratio / 10);
Christoph Lameter81819f02007-05-06 14:49:36 -07004398}
4399
Christoph Lameter98246012008-01-07 23:20:26 -08004400static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s,
Christoph Lameter81819f02007-05-06 14:49:36 -07004401 const char *buf, size_t length)
4402{
Christoph Lameter0121c6192008-04-29 16:11:12 -07004403 unsigned long ratio;
4404 int err;
Christoph Lameter81819f02007-05-06 14:49:36 -07004405
Christoph Lameter0121c6192008-04-29 16:11:12 -07004406 err = strict_strtoul(buf, 10, &ratio);
4407 if (err)
4408 return err;
4409
Christoph Lametere2cb96b2008-08-19 08:51:22 -05004410 if (ratio <= 100)
Christoph Lameter0121c6192008-04-29 16:11:12 -07004411 s->remote_node_defrag_ratio = ratio * 10;
4412
Christoph Lameter81819f02007-05-06 14:49:36 -07004413 return length;
4414}
Christoph Lameter98246012008-01-07 23:20:26 -08004415SLAB_ATTR(remote_node_defrag_ratio);
Christoph Lameter81819f02007-05-06 14:49:36 -07004416#endif
4417
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004418#ifdef CONFIG_SLUB_STATS
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004419static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si)
4420{
4421 unsigned long sum = 0;
4422 int cpu;
4423 int len;
4424 int *data = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL);
4425
4426 if (!data)
4427 return -ENOMEM;
4428
4429 for_each_online_cpu(cpu) {
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06004430 unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si];
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004431
4432 data[cpu] = x;
4433 sum += x;
4434 }
4435
4436 len = sprintf(buf, "%lu", sum);
4437
Christoph Lameter50ef37b2008-04-14 18:52:05 +03004438#ifdef CONFIG_SMP
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004439 for_each_online_cpu(cpu) {
4440 if (data[cpu] && len < PAGE_SIZE - 20)
Christoph Lameter50ef37b2008-04-14 18:52:05 +03004441 len += sprintf(buf + len, " C%d=%u", cpu, data[cpu]);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004442 }
Christoph Lameter50ef37b2008-04-14 18:52:05 +03004443#endif
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004444 kfree(data);
4445 return len + sprintf(buf + len, "\n");
4446}
4447
David Rientjes78eb00c2009-10-15 02:20:22 -07004448static void clear_stat(struct kmem_cache *s, enum stat_item si)
4449{
4450 int cpu;
4451
4452 for_each_online_cpu(cpu)
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06004453 per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0;
David Rientjes78eb00c2009-10-15 02:20:22 -07004454}
4455
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004456#define STAT_ATTR(si, text) \
4457static ssize_t text##_show(struct kmem_cache *s, char *buf) \
4458{ \
4459 return show_stat(s, buf, si); \
4460} \
David Rientjes78eb00c2009-10-15 02:20:22 -07004461static ssize_t text##_store(struct kmem_cache *s, \
4462 const char *buf, size_t length) \
4463{ \
4464 if (buf[0] != '0') \
4465 return -EINVAL; \
4466 clear_stat(s, si); \
4467 return length; \
4468} \
4469SLAB_ATTR(text); \
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004470
4471STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath);
4472STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath);
4473STAT_ATTR(FREE_FASTPATH, free_fastpath);
4474STAT_ATTR(FREE_SLOWPATH, free_slowpath);
4475STAT_ATTR(FREE_FROZEN, free_frozen);
4476STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial);
4477STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial);
4478STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial);
4479STAT_ATTR(ALLOC_SLAB, alloc_slab);
4480STAT_ATTR(ALLOC_REFILL, alloc_refill);
4481STAT_ATTR(FREE_SLAB, free_slab);
4482STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush);
4483STAT_ATTR(DEACTIVATE_FULL, deactivate_full);
4484STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty);
4485STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head);
4486STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail);
4487STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees);
Christoph Lameter65c33762008-04-14 19:11:40 +03004488STAT_ATTR(ORDER_FALLBACK, order_fallback);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004489#endif
4490
Pekka Enberg06428782008-01-07 23:20:27 -08004491static struct attribute *slab_attrs[] = {
Christoph Lameter81819f02007-05-06 14:49:36 -07004492 &slab_size_attr.attr,
4493 &object_size_attr.attr,
4494 &objs_per_slab_attr.attr,
4495 &order_attr.attr,
David Rientjes73d342b2009-02-22 17:40:09 -08004496 &min_partial_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004497 &objects_attr.attr,
Christoph Lameter205ab992008-04-14 19:11:40 +03004498 &objects_partial_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004499 &partial_attr.attr,
4500 &cpu_slabs_attr.attr,
4501 &ctor_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004502 &aliases_attr.attr,
4503 &align_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004504 &hwcache_align_attr.attr,
4505 &reclaim_account_attr.attr,
4506 &destroy_by_rcu_attr.attr,
Christoph Lametera5a84752010-10-05 13:57:27 -05004507 &shrink_attr.attr,
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08004508 &reserved_attr.attr,
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004509#ifdef CONFIG_SLUB_DEBUG
Christoph Lametera5a84752010-10-05 13:57:27 -05004510 &total_objects_attr.attr,
4511 &slabs_attr.attr,
4512 &sanity_checks_attr.attr,
4513 &trace_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004514 &red_zone_attr.attr,
4515 &poison_attr.attr,
4516 &store_user_attr.attr,
Christoph Lameter53e15af2007-05-06 14:49:43 -07004517 &validate_attr.attr,
Christoph Lameter88a420e2007-05-06 14:49:45 -07004518 &alloc_calls_attr.attr,
4519 &free_calls_attr.attr,
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004520#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07004521#ifdef CONFIG_ZONE_DMA
4522 &cache_dma_attr.attr,
4523#endif
4524#ifdef CONFIG_NUMA
Christoph Lameter98246012008-01-07 23:20:26 -08004525 &remote_node_defrag_ratio_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004526#endif
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004527#ifdef CONFIG_SLUB_STATS
4528 &alloc_fastpath_attr.attr,
4529 &alloc_slowpath_attr.attr,
4530 &free_fastpath_attr.attr,
4531 &free_slowpath_attr.attr,
4532 &free_frozen_attr.attr,
4533 &free_add_partial_attr.attr,
4534 &free_remove_partial_attr.attr,
4535 &alloc_from_partial_attr.attr,
4536 &alloc_slab_attr.attr,
4537 &alloc_refill_attr.attr,
4538 &free_slab_attr.attr,
4539 &cpuslab_flush_attr.attr,
4540 &deactivate_full_attr.attr,
4541 &deactivate_empty_attr.attr,
4542 &deactivate_to_head_attr.attr,
4543 &deactivate_to_tail_attr.attr,
4544 &deactivate_remote_frees_attr.attr,
Christoph Lameter65c33762008-04-14 19:11:40 +03004545 &order_fallback_attr.attr,
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004546#endif
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +03004547#ifdef CONFIG_FAILSLAB
4548 &failslab_attr.attr,
4549#endif
4550
Christoph Lameter81819f02007-05-06 14:49:36 -07004551 NULL
4552};
4553
4554static struct attribute_group slab_attr_group = {
4555 .attrs = slab_attrs,
4556};
4557
4558static ssize_t slab_attr_show(struct kobject *kobj,
4559 struct attribute *attr,
4560 char *buf)
4561{
4562 struct slab_attribute *attribute;
4563 struct kmem_cache *s;
4564 int err;
4565
4566 attribute = to_slab_attr(attr);
4567 s = to_slab(kobj);
4568
4569 if (!attribute->show)
4570 return -EIO;
4571
4572 err = attribute->show(s, buf);
4573
4574 return err;
4575}
4576
4577static ssize_t slab_attr_store(struct kobject *kobj,
4578 struct attribute *attr,
4579 const char *buf, size_t len)
4580{
4581 struct slab_attribute *attribute;
4582 struct kmem_cache *s;
4583 int err;
4584
4585 attribute = to_slab_attr(attr);
4586 s = to_slab(kobj);
4587
4588 if (!attribute->store)
4589 return -EIO;
4590
4591 err = attribute->store(s, buf, len);
4592
4593 return err;
4594}
4595
Christoph Lameter151c6022008-01-07 22:29:05 -08004596static void kmem_cache_release(struct kobject *kobj)
4597{
4598 struct kmem_cache *s = to_slab(kobj);
4599
Pekka Enberg84c1cf62010-09-14 23:21:12 +03004600 kfree(s->name);
Christoph Lameter151c6022008-01-07 22:29:05 -08004601 kfree(s);
4602}
4603
Emese Revfy52cf25d2010-01-19 02:58:23 +01004604static const struct sysfs_ops slab_sysfs_ops = {
Christoph Lameter81819f02007-05-06 14:49:36 -07004605 .show = slab_attr_show,
4606 .store = slab_attr_store,
4607};
4608
4609static struct kobj_type slab_ktype = {
4610 .sysfs_ops = &slab_sysfs_ops,
Christoph Lameter151c6022008-01-07 22:29:05 -08004611 .release = kmem_cache_release
Christoph Lameter81819f02007-05-06 14:49:36 -07004612};
4613
4614static int uevent_filter(struct kset *kset, struct kobject *kobj)
4615{
4616 struct kobj_type *ktype = get_ktype(kobj);
4617
4618 if (ktype == &slab_ktype)
4619 return 1;
4620 return 0;
4621}
4622
Emese Revfy9cd43612009-12-31 14:52:51 +01004623static const struct kset_uevent_ops slab_uevent_ops = {
Christoph Lameter81819f02007-05-06 14:49:36 -07004624 .filter = uevent_filter,
4625};
4626
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06004627static struct kset *slab_kset;
Christoph Lameter81819f02007-05-06 14:49:36 -07004628
4629#define ID_STR_LENGTH 64
4630
4631/* Create a unique string id for a slab cache:
Christoph Lameter6446faa2008-02-15 23:45:26 -08004632 *
4633 * Format :[flags-]size
Christoph Lameter81819f02007-05-06 14:49:36 -07004634 */
4635static char *create_unique_id(struct kmem_cache *s)
4636{
4637 char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL);
4638 char *p = name;
4639
4640 BUG_ON(!name);
4641
4642 *p++ = ':';
4643 /*
4644 * First flags affecting slabcache operations. We will only
4645 * get here for aliasable slabs so we do not need to support
4646 * too many flags. The flags here must cover all flags that
4647 * are matched during merging to guarantee that the id is
4648 * unique.
4649 */
4650 if (s->flags & SLAB_CACHE_DMA)
4651 *p++ = 'd';
4652 if (s->flags & SLAB_RECLAIM_ACCOUNT)
4653 *p++ = 'a';
4654 if (s->flags & SLAB_DEBUG_FREE)
4655 *p++ = 'F';
Vegard Nossum5a896d92008-04-04 00:54:48 +02004656 if (!(s->flags & SLAB_NOTRACK))
4657 *p++ = 't';
Christoph Lameter81819f02007-05-06 14:49:36 -07004658 if (p != name + 1)
4659 *p++ = '-';
4660 p += sprintf(p, "%07d", s->size);
4661 BUG_ON(p > name + ID_STR_LENGTH - 1);
4662 return name;
4663}
4664
4665static int sysfs_slab_add(struct kmem_cache *s)
4666{
4667 int err;
4668 const char *name;
4669 int unmergeable;
4670
4671 if (slab_state < SYSFS)
4672 /* Defer until later */
4673 return 0;
4674
4675 unmergeable = slab_unmergeable(s);
4676 if (unmergeable) {
4677 /*
4678 * Slabcache can never be merged so we can use the name proper.
4679 * This is typically the case for debug situations. In that
4680 * case we can catch duplicate names easily.
4681 */
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06004682 sysfs_remove_link(&slab_kset->kobj, s->name);
Christoph Lameter81819f02007-05-06 14:49:36 -07004683 name = s->name;
4684 } else {
4685 /*
4686 * Create a unique name for the slab as a target
4687 * for the symlinks.
4688 */
4689 name = create_unique_id(s);
4690 }
4691
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06004692 s->kobj.kset = slab_kset;
Greg Kroah-Hartman1eada112007-12-17 23:05:35 -07004693 err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, name);
4694 if (err) {
4695 kobject_put(&s->kobj);
Christoph Lameter81819f02007-05-06 14:49:36 -07004696 return err;
Greg Kroah-Hartman1eada112007-12-17 23:05:35 -07004697 }
Christoph Lameter81819f02007-05-06 14:49:36 -07004698
4699 err = sysfs_create_group(&s->kobj, &slab_attr_group);
Xiaotian Feng5788d8a2009-07-22 11:28:53 +08004700 if (err) {
4701 kobject_del(&s->kobj);
4702 kobject_put(&s->kobj);
Christoph Lameter81819f02007-05-06 14:49:36 -07004703 return err;
Xiaotian Feng5788d8a2009-07-22 11:28:53 +08004704 }
Christoph Lameter81819f02007-05-06 14:49:36 -07004705 kobject_uevent(&s->kobj, KOBJ_ADD);
4706 if (!unmergeable) {
4707 /* Setup first alias */
4708 sysfs_slab_alias(s, s->name);
4709 kfree(name);
4710 }
4711 return 0;
4712}
4713
4714static void sysfs_slab_remove(struct kmem_cache *s)
4715{
Christoph Lameter2bce6482010-07-19 11:39:11 -05004716 if (slab_state < SYSFS)
4717 /*
4718 * Sysfs has not been setup yet so no need to remove the
4719 * cache from sysfs.
4720 */
4721 return;
4722
Christoph Lameter81819f02007-05-06 14:49:36 -07004723 kobject_uevent(&s->kobj, KOBJ_REMOVE);
4724 kobject_del(&s->kobj);
Christoph Lameter151c6022008-01-07 22:29:05 -08004725 kobject_put(&s->kobj);
Christoph Lameter81819f02007-05-06 14:49:36 -07004726}
4727
4728/*
4729 * Need to buffer aliases during bootup until sysfs becomes
Nick Andrew9f6c708e2008-12-05 14:08:08 +11004730 * available lest we lose that information.
Christoph Lameter81819f02007-05-06 14:49:36 -07004731 */
4732struct saved_alias {
4733 struct kmem_cache *s;
4734 const char *name;
4735 struct saved_alias *next;
4736};
4737
Adrian Bunk5af328a2007-07-17 04:03:27 -07004738static struct saved_alias *alias_list;
Christoph Lameter81819f02007-05-06 14:49:36 -07004739
4740static int sysfs_slab_alias(struct kmem_cache *s, const char *name)
4741{
4742 struct saved_alias *al;
4743
4744 if (slab_state == SYSFS) {
4745 /*
4746 * If we have a leftover link then remove it.
4747 */
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06004748 sysfs_remove_link(&slab_kset->kobj, name);
4749 return sysfs_create_link(&slab_kset->kobj, &s->kobj, name);
Christoph Lameter81819f02007-05-06 14:49:36 -07004750 }
4751
4752 al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL);
4753 if (!al)
4754 return -ENOMEM;
4755
4756 al->s = s;
4757 al->name = name;
4758 al->next = alias_list;
4759 alias_list = al;
4760 return 0;
4761}
4762
4763static int __init slab_sysfs_init(void)
4764{
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07004765 struct kmem_cache *s;
Christoph Lameter81819f02007-05-06 14:49:36 -07004766 int err;
4767
Christoph Lameter2bce6482010-07-19 11:39:11 -05004768 down_write(&slub_lock);
4769
Greg Kroah-Hartman0ff21e42007-11-06 10:36:58 -08004770 slab_kset = kset_create_and_add("slab", &slab_uevent_ops, kernel_kobj);
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06004771 if (!slab_kset) {
Christoph Lameter2bce6482010-07-19 11:39:11 -05004772 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07004773 printk(KERN_ERR "Cannot register slab subsystem.\n");
4774 return -ENOSYS;
4775 }
4776
Christoph Lameter26a7bd02007-05-09 02:32:39 -07004777 slab_state = SYSFS;
4778
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07004779 list_for_each_entry(s, &slab_caches, list) {
Christoph Lameter26a7bd02007-05-09 02:32:39 -07004780 err = sysfs_slab_add(s);
Christoph Lameter5d540fb2007-08-30 23:56:26 -07004781 if (err)
4782 printk(KERN_ERR "SLUB: Unable to add boot slab %s"
4783 " to sysfs\n", s->name);
Christoph Lameter26a7bd02007-05-09 02:32:39 -07004784 }
Christoph Lameter81819f02007-05-06 14:49:36 -07004785
4786 while (alias_list) {
4787 struct saved_alias *al = alias_list;
4788
4789 alias_list = alias_list->next;
4790 err = sysfs_slab_alias(al->s, al->name);
Christoph Lameter5d540fb2007-08-30 23:56:26 -07004791 if (err)
4792 printk(KERN_ERR "SLUB: Unable to add boot slab alias"
4793 " %s to sysfs\n", s->name);
Christoph Lameter81819f02007-05-06 14:49:36 -07004794 kfree(al);
4795 }
4796
Christoph Lameter2bce6482010-07-19 11:39:11 -05004797 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07004798 resiliency_test();
4799 return 0;
4800}
4801
4802__initcall(slab_sysfs_init);
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004803#endif /* CONFIG_SYSFS */
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004804
4805/*
4806 * The /proc/slabinfo ABI
4807 */
Linus Torvalds158a9622008-01-02 13:04:48 -08004808#ifdef CONFIG_SLABINFO
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004809static void print_slabinfo_header(struct seq_file *m)
4810{
4811 seq_puts(m, "slabinfo - version: 2.1\n");
4812 seq_puts(m, "# name <active_objs> <num_objs> <objsize> "
4813 "<objperslab> <pagesperslab>");
4814 seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
4815 seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
4816 seq_putc(m, '\n');
4817}
4818
4819static void *s_start(struct seq_file *m, loff_t *pos)
4820{
4821 loff_t n = *pos;
4822
4823 down_read(&slub_lock);
4824 if (!n)
4825 print_slabinfo_header(m);
4826
4827 return seq_list_start(&slab_caches, *pos);
4828}
4829
4830static void *s_next(struct seq_file *m, void *p, loff_t *pos)
4831{
4832 return seq_list_next(p, &slab_caches, pos);
4833}
4834
4835static void s_stop(struct seq_file *m, void *p)
4836{
4837 up_read(&slub_lock);
4838}
4839
4840static int s_show(struct seq_file *m, void *p)
4841{
4842 unsigned long nr_partials = 0;
4843 unsigned long nr_slabs = 0;
4844 unsigned long nr_inuse = 0;
Christoph Lameter205ab992008-04-14 19:11:40 +03004845 unsigned long nr_objs = 0;
4846 unsigned long nr_free = 0;
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004847 struct kmem_cache *s;
4848 int node;
4849
4850 s = list_entry(p, struct kmem_cache, list);
4851
4852 for_each_online_node(node) {
4853 struct kmem_cache_node *n = get_node(s, node);
4854
4855 if (!n)
4856 continue;
4857
4858 nr_partials += n->nr_partial;
4859 nr_slabs += atomic_long_read(&n->nr_slabs);
Christoph Lameter205ab992008-04-14 19:11:40 +03004860 nr_objs += atomic_long_read(&n->total_objects);
4861 nr_free += count_partial(n, count_free);
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004862 }
4863
Christoph Lameter205ab992008-04-14 19:11:40 +03004864 nr_inuse = nr_objs - nr_free;
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004865
4866 seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", s->name, nr_inuse,
Christoph Lameter834f3d12008-04-14 19:11:31 +03004867 nr_objs, s->size, oo_objects(s->oo),
4868 (1 << oo_order(s->oo)));
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004869 seq_printf(m, " : tunables %4u %4u %4u", 0, 0, 0);
4870 seq_printf(m, " : slabdata %6lu %6lu %6lu", nr_slabs, nr_slabs,
4871 0UL);
4872 seq_putc(m, '\n');
4873 return 0;
4874}
4875
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +04004876static const struct seq_operations slabinfo_op = {
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004877 .start = s_start,
4878 .next = s_next,
4879 .stop = s_stop,
4880 .show = s_show,
4881};
4882
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +04004883static int slabinfo_open(struct inode *inode, struct file *file)
4884{
4885 return seq_open(file, &slabinfo_op);
4886}
4887
4888static const struct file_operations proc_slabinfo_operations = {
4889 .open = slabinfo_open,
4890 .read = seq_read,
4891 .llseek = seq_lseek,
4892 .release = seq_release,
4893};
4894
4895static int __init slab_proc_init(void)
4896{
WANG Congcf5d1132009-08-18 19:11:40 +03004897 proc_create("slabinfo", S_IRUGO, NULL, &proc_slabinfo_operations);
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +04004898 return 0;
4899}
4900module_init(slab_proc_init);
Linus Torvalds158a9622008-01-02 13:04:48 -08004901#endif /* CONFIG_SLABINFO */