blob: 4982fb5c91dea290dc262dd62bfce8b5e7d92c40 [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 *
Christoph Lameter881db7f2011-06-01 12:25:53 -05005 * The allocator synchronizes using per slab locks or atomic operatios
6 * and only uses a centralized lock to manage a pool of partial slabs.
Christoph Lameter81819f02007-05-06 14:49:36 -07007 *
Christoph Lametercde53532008-07-04 09:59:22 -07008 * (C) 2007 SGI, Christoph Lameter
Christoph Lameter881db7f2011-06-01 12:25:53 -05009 * (C) 2011 Linux Foundation, Christoph Lameter
Christoph Lameter81819f02007-05-06 14:49:36 -070010 */
11
12#include <linux/mm.h>
Nick Piggin1eb5ac62009-05-05 19:13:44 +100013#include <linux/swap.h> /* struct reclaim_state */
Christoph Lameter81819f02007-05-06 14:49:36 -070014#include <linux/module.h>
15#include <linux/bit_spinlock.h>
16#include <linux/interrupt.h>
17#include <linux/bitops.h>
18#include <linux/slab.h>
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +040019#include <linux/proc_fs.h>
Christoph Lameter81819f02007-05-06 14:49:36 -070020#include <linux/seq_file.h>
Vegard Nossum5a896d92008-04-04 00:54:48 +020021#include <linux/kmemcheck.h>
Christoph Lameter81819f02007-05-06 14:49:36 -070022#include <linux/cpu.h>
23#include <linux/cpuset.h>
24#include <linux/mempolicy.h>
25#include <linux/ctype.h>
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -070026#include <linux/debugobjects.h>
Christoph Lameter81819f02007-05-06 14:49:36 -070027#include <linux/kallsyms.h>
Yasunori Gotob9049e22007-10-21 16:41:37 -070028#include <linux/memory.h>
Roman Zippelf8bd2252008-05-01 04:34:31 -070029#include <linux/math64.h>
Akinobu Mita773ff602008-12-23 19:37:01 +090030#include <linux/fault-inject.h>
Pekka Enbergbfa71452011-07-07 22:47:01 +030031#include <linux/stacktrace.h>
Christoph Lameter81819f02007-05-06 14:49:36 -070032
Richard Kennedy4a923792010-10-21 10:29:19 +010033#include <trace/events/kmem.h>
34
Christoph Lameter81819f02007-05-06 14:49:36 -070035/*
36 * Lock order:
Christoph Lameter881db7f2011-06-01 12:25:53 -050037 * 1. slub_lock (Global Semaphore)
38 * 2. node->list_lock
39 * 3. slab_lock(page) (Only on some arches and for debugging)
Christoph Lameter81819f02007-05-06 14:49:36 -070040 *
Christoph Lameter881db7f2011-06-01 12:25:53 -050041 * slub_lock
42 *
43 * The role of the slub_lock is to protect the list of all the slabs
44 * and to synchronize major metadata changes to slab cache structures.
45 *
46 * The slab_lock is only used for debugging and on arches that do not
47 * have the ability to do a cmpxchg_double. It only protects the second
48 * double word in the page struct. Meaning
49 * A. page->freelist -> List of object free in a page
50 * B. page->counters -> Counters of objects
51 * C. page->frozen -> frozen state
52 *
53 * If a slab is frozen then it is exempt from list management. It is not
54 * on any list. The processor that froze the slab is the one who can
55 * perform list operations on the page. Other processors may put objects
56 * onto the freelist but the processor that froze the slab is the only
57 * one that can retrieve the objects from the page's freelist.
Christoph Lameter81819f02007-05-06 14:49:36 -070058 *
59 * The list_lock protects the partial and full list on each node and
60 * the partial slab counter. If taken then no new slabs may be added or
61 * removed from the lists nor make the number of partial slabs be modified.
62 * (Note that the total number of slabs is an atomic value that may be
63 * modified without taking the list lock).
64 *
65 * The list_lock is a centralized lock and thus we avoid taking it as
66 * much as possible. As long as SLUB does not have to handle partial
67 * slabs, operations can continue without any centralized lock. F.e.
68 * allocating a long series of objects that fill up slabs does not require
69 * the list lock.
Christoph Lameter81819f02007-05-06 14:49:36 -070070 * 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 Lameterb789ef52011-06-01 12:25:49 -0500134/* Enable to log cmpxchg failures */
135#undef SLUB_DEBUG_CMPXCHG
136
Christoph Lameter81819f02007-05-06 14:49:36 -0700137/*
Christoph Lameter2086d262007-05-06 14:49:46 -0700138 * Mininum number of partial slabs. These will be left on the partial
139 * lists even if they are empty. kmem_cache_shrink may reclaim them.
140 */
Christoph Lameter76be8952007-12-21 14:37:37 -0800141#define MIN_PARTIAL 5
Christoph Lametere95eed52007-05-06 14:49:44 -0700142
Christoph Lameter2086d262007-05-06 14:49:46 -0700143/*
144 * Maximum number of desirable partial slabs.
145 * The existence of more partial slabs makes kmem_cache_shrink
146 * sort the partial list by the number of objects in the.
147 */
148#define MAX_PARTIAL 10
149
Christoph Lameter81819f02007-05-06 14:49:36 -0700150#define DEBUG_DEFAULT_FLAGS (SLAB_DEBUG_FREE | SLAB_RED_ZONE | \
151 SLAB_POISON | SLAB_STORE_USER)
Christoph Lameter672bba32007-05-09 02:32:39 -0700152
Christoph Lameter81819f02007-05-06 14:49:36 -0700153/*
David Rientjes3de47212009-07-27 18:30:35 -0700154 * Debugging flags that require metadata to be stored in the slab. These get
155 * disabled when slub_debug=O is used and a cache's min order increases with
156 * metadata.
David Rientjesfa5ec8a2009-07-07 00:14:14 -0700157 */
David Rientjes3de47212009-07-27 18:30:35 -0700158#define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
David Rientjesfa5ec8a2009-07-07 00:14:14 -0700159
160/*
Christoph Lameter81819f02007-05-06 14:49:36 -0700161 * Set of flags that will prevent slab merging
162 */
163#define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +0300164 SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \
165 SLAB_FAILSLAB)
Christoph Lameter81819f02007-05-06 14:49:36 -0700166
167#define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \
Vegard Nossum5a896d92008-04-04 00:54:48 +0200168 SLAB_CACHE_DMA | SLAB_NOTRACK)
Christoph Lameter81819f02007-05-06 14:49:36 -0700169
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400170#define OO_SHIFT 16
171#define OO_MASK ((1 << OO_SHIFT) - 1)
Christoph Lameter50d5c412011-06-01 12:25:45 -0500172#define MAX_OBJS_PER_PAGE 32767 /* since page.objects is u15 */
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400173
Christoph Lameter81819f02007-05-06 14:49:36 -0700174/* Internal SLUB flags */
Christoph Lameterf90ec392010-07-09 14:07:11 -0500175#define __OBJECT_POISON 0x80000000UL /* Poison object */
Christoph Lameterb789ef52011-06-01 12:25:49 -0500176#define __CMPXCHG_DOUBLE 0x40000000UL /* Use cmpxchg_double */
Christoph Lameter81819f02007-05-06 14:49:36 -0700177
178static int kmem_size = sizeof(struct kmem_cache);
179
180#ifdef CONFIG_SMP
181static struct notifier_block slab_notifier;
182#endif
183
184static enum {
185 DOWN, /* No slab functionality available */
Christoph Lameter51df1142010-08-20 12:37:15 -0500186 PARTIAL, /* Kmem_cache_node works */
Christoph Lameter672bba32007-05-09 02:32:39 -0700187 UP, /* Everything works but does not show up in sysfs */
Christoph Lameter81819f02007-05-06 14:49:36 -0700188 SYSFS /* Sysfs up */
189} slab_state = DOWN;
190
191/* A list of all slab caches on the system */
192static DECLARE_RWSEM(slub_lock);
Adrian Bunk5af328a2007-07-17 04:03:27 -0700193static LIST_HEAD(slab_caches);
Christoph Lameter81819f02007-05-06 14:49:36 -0700194
Christoph Lameter02cbc872007-05-09 02:32:43 -0700195/*
196 * Tracking user of a slab.
197 */
Ben Greeard6543e32011-07-07 11:36:36 -0700198#define TRACK_ADDRS_COUNT 16
Christoph Lameter02cbc872007-05-09 02:32:43 -0700199struct track {
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300200 unsigned long addr; /* Called from address */
Ben Greeard6543e32011-07-07 11:36:36 -0700201#ifdef CONFIG_STACKTRACE
202 unsigned long addrs[TRACK_ADDRS_COUNT]; /* Called from address */
203#endif
Christoph Lameter02cbc872007-05-09 02:32:43 -0700204 int cpu; /* Was running on cpu */
205 int pid; /* Pid context */
206 unsigned long when; /* When did the operation occur */
207};
208
209enum track_item { TRACK_ALLOC, TRACK_FREE };
210
Christoph Lameterab4d5ed2010-10-05 13:57:26 -0500211#ifdef CONFIG_SYSFS
Christoph Lameter81819f02007-05-06 14:49:36 -0700212static int sysfs_slab_add(struct kmem_cache *);
213static int sysfs_slab_alias(struct kmem_cache *, const char *);
214static void sysfs_slab_remove(struct kmem_cache *);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800215
Christoph Lameter81819f02007-05-06 14:49:36 -0700216#else
Christoph Lameter0c710012007-07-17 04:03:24 -0700217static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; }
218static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p)
219 { return 0; }
Christoph Lameter151c6022008-01-07 22:29:05 -0800220static inline void sysfs_slab_remove(struct kmem_cache *s)
221{
Pekka Enberg84c1cf62010-09-14 23:21:12 +0300222 kfree(s->name);
Christoph Lameter151c6022008-01-07 22:29:05 -0800223 kfree(s);
224}
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800225
Christoph Lameter81819f02007-05-06 14:49:36 -0700226#endif
227
Christoph Lameter4fdccdf2011-03-22 13:35:00 -0500228static inline void stat(const struct kmem_cache *s, enum stat_item si)
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800229{
230#ifdef CONFIG_SLUB_STATS
Christoph Lameter84e554e62009-12-18 16:26:23 -0600231 __this_cpu_inc(s->cpu_slab->stat[si]);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800232#endif
233}
234
Christoph Lameter81819f02007-05-06 14:49:36 -0700235/********************************************************************
236 * Core slab cache functions
237 *******************************************************************/
238
239int slab_is_available(void)
240{
241 return slab_state >= UP;
242}
243
244static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
245{
Christoph Lameter81819f02007-05-06 14:49:36 -0700246 return s->node[node];
Christoph Lameter81819f02007-05-06 14:49:36 -0700247}
248
Christoph Lameter6446faa2008-02-15 23:45:26 -0800249/* Verify that a pointer has an address that is valid within a slab page */
Christoph Lameter02cbc872007-05-09 02:32:43 -0700250static inline int check_valid_pointer(struct kmem_cache *s,
251 struct page *page, const void *object)
252{
253 void *base;
254
Christoph Lametera973e9d2008-03-01 13:40:44 -0800255 if (!object)
Christoph Lameter02cbc872007-05-09 02:32:43 -0700256 return 1;
257
Christoph Lametera973e9d2008-03-01 13:40:44 -0800258 base = page_address(page);
Christoph Lameter39b26462008-04-14 19:11:30 +0300259 if (object < base || object >= base + page->objects * s->size ||
Christoph Lameter02cbc872007-05-09 02:32:43 -0700260 (object - base) % s->size) {
261 return 0;
262 }
263
264 return 1;
265}
266
Christoph Lameter7656c722007-05-09 02:32:40 -0700267static inline void *get_freepointer(struct kmem_cache *s, void *object)
268{
269 return *(void **)(object + s->offset);
270}
271
Christoph Lameter1393d9a2011-05-16 15:26:08 -0500272static inline void *get_freepointer_safe(struct kmem_cache *s, void *object)
273{
274 void *p;
275
276#ifdef CONFIG_DEBUG_PAGEALLOC
277 probe_kernel_read(&p, (void **)(object + s->offset), sizeof(p));
278#else
279 p = get_freepointer(s, object);
280#endif
281 return p;
282}
283
Christoph Lameter7656c722007-05-09 02:32:40 -0700284static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp)
285{
286 *(void **)(object + s->offset) = fp;
287}
288
289/* Loop over all objects in a slab */
Christoph Lameter224a88b2008-04-14 19:11:31 +0300290#define for_each_object(__p, __s, __addr, __objects) \
291 for (__p = (__addr); __p < (__addr) + (__objects) * (__s)->size;\
Christoph Lameter7656c722007-05-09 02:32:40 -0700292 __p += (__s)->size)
293
Christoph Lameter7656c722007-05-09 02:32:40 -0700294/* Determine object index from a given position */
295static inline int slab_index(void *p, struct kmem_cache *s, void *addr)
296{
297 return (p - addr) / s->size;
298}
299
Mariusz Kozlowskid71f6062011-02-26 20:10:26 +0100300static inline size_t slab_ksize(const struct kmem_cache *s)
301{
302#ifdef CONFIG_SLUB_DEBUG
303 /*
304 * Debugging requires use of the padding between object
305 * and whatever may come after it.
306 */
307 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
308 return s->objsize;
309
310#endif
311 /*
312 * If we have the need to store the freelist pointer
313 * back there or track user information then we can
314 * only use the space before that information.
315 */
316 if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER))
317 return s->inuse;
318 /*
319 * Else we can use all the padding etc for the allocation
320 */
321 return s->size;
322}
323
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800324static inline int order_objects(int order, unsigned long size, int reserved)
325{
326 return ((PAGE_SIZE << order) - reserved) / size;
327}
328
Christoph Lameter834f3d12008-04-14 19:11:31 +0300329static inline struct kmem_cache_order_objects oo_make(int order,
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800330 unsigned long size, int reserved)
Christoph Lameter834f3d12008-04-14 19:11:31 +0300331{
332 struct kmem_cache_order_objects x = {
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800333 (order << OO_SHIFT) + order_objects(order, size, reserved)
Christoph Lameter834f3d12008-04-14 19:11:31 +0300334 };
335
336 return x;
337}
338
339static inline int oo_order(struct kmem_cache_order_objects x)
340{
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400341 return x.x >> OO_SHIFT;
Christoph Lameter834f3d12008-04-14 19:11:31 +0300342}
343
344static inline int oo_objects(struct kmem_cache_order_objects x)
345{
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400346 return x.x & OO_MASK;
Christoph Lameter834f3d12008-04-14 19:11:31 +0300347}
348
Christoph Lameter881db7f2011-06-01 12:25:53 -0500349/*
350 * Per slab locking using the pagelock
351 */
352static __always_inline void slab_lock(struct page *page)
353{
354 bit_spin_lock(PG_locked, &page->flags);
355}
356
357static __always_inline void slab_unlock(struct page *page)
358{
359 __bit_spin_unlock(PG_locked, &page->flags);
360}
361
Christoph Lameter1d071712011-07-14 12:49:12 -0500362/* Interrupts must be disabled (for the fallback code to work right) */
363static inline bool __cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
Christoph Lameterb789ef52011-06-01 12:25:49 -0500364 void *freelist_old, unsigned long counters_old,
365 void *freelist_new, unsigned long counters_new,
366 const char *n)
367{
Christoph Lameter1d071712011-07-14 12:49:12 -0500368 VM_BUG_ON(!irqs_disabled());
Christoph Lameterb789ef52011-06-01 12:25:49 -0500369#ifdef CONFIG_CMPXCHG_DOUBLE
370 if (s->flags & __CMPXCHG_DOUBLE) {
371 if (cmpxchg_double(&page->freelist,
372 freelist_old, counters_old,
373 freelist_new, counters_new))
374 return 1;
375 } else
376#endif
377 {
Christoph Lameter881db7f2011-06-01 12:25:53 -0500378 slab_lock(page);
Christoph Lameterb789ef52011-06-01 12:25:49 -0500379 if (page->freelist == freelist_old && page->counters == counters_old) {
380 page->freelist = freelist_new;
381 page->counters = counters_new;
Christoph Lameter881db7f2011-06-01 12:25:53 -0500382 slab_unlock(page);
Christoph Lameterb789ef52011-06-01 12:25:49 -0500383 return 1;
384 }
Christoph Lameter881db7f2011-06-01 12:25:53 -0500385 slab_unlock(page);
Christoph Lameterb789ef52011-06-01 12:25:49 -0500386 }
387
388 cpu_relax();
389 stat(s, CMPXCHG_DOUBLE_FAIL);
390
391#ifdef SLUB_DEBUG_CMPXCHG
392 printk(KERN_INFO "%s %s: cmpxchg double redo ", n, s->name);
393#endif
394
395 return 0;
396}
397
Christoph Lameter1d071712011-07-14 12:49:12 -0500398static inline bool cmpxchg_double_slab(struct kmem_cache *s, struct page *page,
399 void *freelist_old, unsigned long counters_old,
400 void *freelist_new, unsigned long counters_new,
401 const char *n)
402{
403#ifdef CONFIG_CMPXCHG_DOUBLE
404 if (s->flags & __CMPXCHG_DOUBLE) {
405 if (cmpxchg_double(&page->freelist,
406 freelist_old, counters_old,
407 freelist_new, counters_new))
408 return 1;
409 } else
410#endif
411 {
412 unsigned long flags;
413
414 local_irq_save(flags);
415 slab_lock(page);
416 if (page->freelist == freelist_old && page->counters == counters_old) {
417 page->freelist = freelist_new;
418 page->counters = counters_new;
419 slab_unlock(page);
420 local_irq_restore(flags);
421 return 1;
422 }
423 slab_unlock(page);
424 local_irq_restore(flags);
425 }
426
427 cpu_relax();
428 stat(s, CMPXCHG_DOUBLE_FAIL);
429
430#ifdef SLUB_DEBUG_CMPXCHG
431 printk(KERN_INFO "%s %s: cmpxchg double redo ", n, s->name);
432#endif
433
434 return 0;
435}
436
Christoph Lameter41ecc552007-05-09 02:32:44 -0700437#ifdef CONFIG_SLUB_DEBUG
438/*
Christoph Lameter5f80b132011-04-15 14:48:13 -0500439 * Determine a map of object in use on a page.
440 *
Christoph Lameter881db7f2011-06-01 12:25:53 -0500441 * Node listlock must be held to guarantee that the page does
Christoph Lameter5f80b132011-04-15 14:48:13 -0500442 * not vanish from under us.
443 */
444static void get_map(struct kmem_cache *s, struct page *page, unsigned long *map)
445{
446 void *p;
447 void *addr = page_address(page);
448
449 for (p = page->freelist; p; p = get_freepointer(s, p))
450 set_bit(slab_index(p, s, addr), map);
451}
452
Christoph Lameter41ecc552007-05-09 02:32:44 -0700453/*
454 * Debug settings:
455 */
Christoph Lameterf0630ff2007-07-15 23:38:14 -0700456#ifdef CONFIG_SLUB_DEBUG_ON
457static int slub_debug = DEBUG_DEFAULT_FLAGS;
458#else
Christoph Lameter41ecc552007-05-09 02:32:44 -0700459static int slub_debug;
Christoph Lameterf0630ff2007-07-15 23:38:14 -0700460#endif
Christoph Lameter41ecc552007-05-09 02:32:44 -0700461
462static char *slub_debug_slabs;
David Rientjesfa5ec8a2009-07-07 00:14:14 -0700463static int disable_higher_order_debug;
Christoph Lameter41ecc552007-05-09 02:32:44 -0700464
Christoph Lameter7656c722007-05-09 02:32:40 -0700465/*
Christoph Lameter81819f02007-05-06 14:49:36 -0700466 * Object debugging
467 */
468static void print_section(char *text, u8 *addr, unsigned int length)
469{
470 int i, offset;
471 int newline = 1;
472 char ascii[17];
473
474 ascii[16] = 0;
475
476 for (i = 0; i < length; i++) {
477 if (newline) {
Christoph Lameter24922682007-07-17 04:03:18 -0700478 printk(KERN_ERR "%8s 0x%p: ", text, addr + i);
Christoph Lameter81819f02007-05-06 14:49:36 -0700479 newline = 0;
480 }
Pekka Enberg06428782008-01-07 23:20:27 -0800481 printk(KERN_CONT " %02x", addr[i]);
Christoph Lameter81819f02007-05-06 14:49:36 -0700482 offset = i % 16;
483 ascii[offset] = isgraph(addr[i]) ? addr[i] : '.';
484 if (offset == 15) {
Pekka Enberg06428782008-01-07 23:20:27 -0800485 printk(KERN_CONT " %s\n", ascii);
Christoph Lameter81819f02007-05-06 14:49:36 -0700486 newline = 1;
487 }
488 }
489 if (!newline) {
490 i %= 16;
491 while (i < 16) {
Pekka Enberg06428782008-01-07 23:20:27 -0800492 printk(KERN_CONT " ");
Christoph Lameter81819f02007-05-06 14:49:36 -0700493 ascii[i] = ' ';
494 i++;
495 }
Pekka Enberg06428782008-01-07 23:20:27 -0800496 printk(KERN_CONT " %s\n", ascii);
Christoph Lameter81819f02007-05-06 14:49:36 -0700497 }
498}
499
Christoph Lameter81819f02007-05-06 14:49:36 -0700500static struct track *get_track(struct kmem_cache *s, void *object,
501 enum track_item alloc)
502{
503 struct track *p;
504
505 if (s->offset)
506 p = object + s->offset + sizeof(void *);
507 else
508 p = object + s->inuse;
509
510 return p + alloc;
511}
512
513static void set_track(struct kmem_cache *s, void *object,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300514 enum track_item alloc, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -0700515{
Akinobu Mita1a00df42009-03-07 00:36:21 +0900516 struct track *p = get_track(s, object, alloc);
Christoph Lameter81819f02007-05-06 14:49:36 -0700517
Christoph Lameter81819f02007-05-06 14:49:36 -0700518 if (addr) {
Ben Greeard6543e32011-07-07 11:36:36 -0700519#ifdef CONFIG_STACKTRACE
520 struct stack_trace trace;
521 int i;
522
523 trace.nr_entries = 0;
524 trace.max_entries = TRACK_ADDRS_COUNT;
525 trace.entries = p->addrs;
526 trace.skip = 3;
527 save_stack_trace(&trace);
528
529 /* See rant in lockdep.c */
530 if (trace.nr_entries != 0 &&
531 trace.entries[trace.nr_entries - 1] == ULONG_MAX)
532 trace.nr_entries--;
533
534 for (i = trace.nr_entries; i < TRACK_ADDRS_COUNT; i++)
535 p->addrs[i] = 0;
536#endif
Christoph Lameter81819f02007-05-06 14:49:36 -0700537 p->addr = addr;
538 p->cpu = smp_processor_id();
Alexey Dobriyan88e4ccf2008-06-23 02:58:37 +0400539 p->pid = current->pid;
Christoph Lameter81819f02007-05-06 14:49:36 -0700540 p->when = jiffies;
541 } else
542 memset(p, 0, sizeof(struct track));
543}
544
Christoph Lameter81819f02007-05-06 14:49:36 -0700545static void init_tracking(struct kmem_cache *s, void *object)
546{
Christoph Lameter24922682007-07-17 04:03:18 -0700547 if (!(s->flags & SLAB_STORE_USER))
548 return;
549
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300550 set_track(s, object, TRACK_FREE, 0UL);
551 set_track(s, object, TRACK_ALLOC, 0UL);
Christoph Lameter81819f02007-05-06 14:49:36 -0700552}
553
554static void print_track(const char *s, struct track *t)
555{
556 if (!t->addr)
557 return;
558
Linus Torvalds7daf7052008-07-14 12:12:53 -0700559 printk(KERN_ERR "INFO: %s in %pS age=%lu cpu=%u pid=%d\n",
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300560 s, (void *)t->addr, jiffies - t->when, t->cpu, t->pid);
Ben Greeard6543e32011-07-07 11:36:36 -0700561#ifdef CONFIG_STACKTRACE
562 {
563 int i;
564 for (i = 0; i < TRACK_ADDRS_COUNT; i++)
565 if (t->addrs[i])
566 printk(KERN_ERR "\t%pS\n", (void *)t->addrs[i]);
567 else
568 break;
569 }
570#endif
Christoph Lameter81819f02007-05-06 14:49:36 -0700571}
572
Christoph Lameter24922682007-07-17 04:03:18 -0700573static void print_tracking(struct kmem_cache *s, void *object)
574{
575 if (!(s->flags & SLAB_STORE_USER))
576 return;
577
578 print_track("Allocated", get_track(s, object, TRACK_ALLOC));
579 print_track("Freed", get_track(s, object, TRACK_FREE));
580}
581
582static void print_page_info(struct page *page)
583{
Christoph Lameter39b26462008-04-14 19:11:30 +0300584 printk(KERN_ERR "INFO: Slab 0x%p objects=%u used=%u fp=0x%p flags=0x%04lx\n",
585 page, page->objects, page->inuse, page->freelist, page->flags);
Christoph Lameter24922682007-07-17 04:03:18 -0700586
587}
588
589static void slab_bug(struct kmem_cache *s, char *fmt, ...)
590{
591 va_list args;
592 char buf[100];
593
594 va_start(args, fmt);
595 vsnprintf(buf, sizeof(buf), fmt, args);
596 va_end(args);
597 printk(KERN_ERR "========================================"
598 "=====================================\n");
599 printk(KERN_ERR "BUG %s: %s\n", s->name, buf);
600 printk(KERN_ERR "----------------------------------------"
601 "-------------------------------------\n\n");
602}
603
604static void slab_fix(struct kmem_cache *s, char *fmt, ...)
605{
606 va_list args;
607 char buf[100];
608
609 va_start(args, fmt);
610 vsnprintf(buf, sizeof(buf), fmt, args);
611 va_end(args);
612 printk(KERN_ERR "FIX %s: %s\n", s->name, buf);
613}
614
615static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p)
Christoph Lameter81819f02007-05-06 14:49:36 -0700616{
617 unsigned int off; /* Offset of last byte */
Christoph Lametera973e9d2008-03-01 13:40:44 -0800618 u8 *addr = page_address(page);
Christoph Lameter24922682007-07-17 04:03:18 -0700619
620 print_tracking(s, p);
621
622 print_page_info(page);
623
624 printk(KERN_ERR "INFO: Object 0x%p @offset=%tu fp=0x%p\n\n",
625 p, p - addr, get_freepointer(s, p));
626
627 if (p > addr + 16)
628 print_section("Bytes b4", p - 16, 16);
629
Pekka Enberg0ebd6522008-07-19 14:17:22 +0300630 print_section("Object", p, min_t(unsigned long, s->objsize, PAGE_SIZE));
Christoph Lameter81819f02007-05-06 14:49:36 -0700631
632 if (s->flags & SLAB_RED_ZONE)
633 print_section("Redzone", p + s->objsize,
634 s->inuse - s->objsize);
635
Christoph Lameter81819f02007-05-06 14:49:36 -0700636 if (s->offset)
637 off = s->offset + sizeof(void *);
638 else
639 off = s->inuse;
640
Christoph Lameter24922682007-07-17 04:03:18 -0700641 if (s->flags & SLAB_STORE_USER)
Christoph Lameter81819f02007-05-06 14:49:36 -0700642 off += 2 * sizeof(struct track);
Christoph Lameter81819f02007-05-06 14:49:36 -0700643
644 if (off != s->size)
645 /* Beginning of the filler is the free pointer */
Christoph Lameter24922682007-07-17 04:03:18 -0700646 print_section("Padding", p + off, s->size - off);
647
648 dump_stack();
Christoph Lameter81819f02007-05-06 14:49:36 -0700649}
650
651static void object_err(struct kmem_cache *s, struct page *page,
652 u8 *object, char *reason)
653{
Christoph Lameter3dc50632008-04-23 12:28:01 -0700654 slab_bug(s, "%s", reason);
Christoph Lameter24922682007-07-17 04:03:18 -0700655 print_trailer(s, page, object);
Christoph Lameter81819f02007-05-06 14:49:36 -0700656}
657
Christoph Lameter24922682007-07-17 04:03:18 -0700658static void slab_err(struct kmem_cache *s, struct page *page, char *fmt, ...)
Christoph Lameter81819f02007-05-06 14:49:36 -0700659{
660 va_list args;
661 char buf[100];
662
Christoph Lameter24922682007-07-17 04:03:18 -0700663 va_start(args, fmt);
664 vsnprintf(buf, sizeof(buf), fmt, args);
Christoph Lameter81819f02007-05-06 14:49:36 -0700665 va_end(args);
Christoph Lameter3dc50632008-04-23 12:28:01 -0700666 slab_bug(s, "%s", buf);
Christoph Lameter24922682007-07-17 04:03:18 -0700667 print_page_info(page);
Christoph Lameter81819f02007-05-06 14:49:36 -0700668 dump_stack();
669}
670
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500671static void init_object(struct kmem_cache *s, void *object, u8 val)
Christoph Lameter81819f02007-05-06 14:49:36 -0700672{
673 u8 *p = object;
674
675 if (s->flags & __OBJECT_POISON) {
676 memset(p, POISON_FREE, s->objsize - 1);
Pekka Enberg06428782008-01-07 23:20:27 -0800677 p[s->objsize - 1] = POISON_END;
Christoph Lameter81819f02007-05-06 14:49:36 -0700678 }
679
680 if (s->flags & SLAB_RED_ZONE)
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500681 memset(p + s->objsize, val, s->inuse - s->objsize);
Christoph Lameter81819f02007-05-06 14:49:36 -0700682}
683
Marcin Slusarzc4089f92011-06-26 21:39:18 +0200684static u8 *check_bytes8(u8 *start, u8 value, unsigned int bytes)
Christoph Lameter81819f02007-05-06 14:49:36 -0700685{
686 while (bytes) {
Marcin Slusarzc4089f92011-06-26 21:39:18 +0200687 if (*start != value)
Christoph Lameter24922682007-07-17 04:03:18 -0700688 return start;
Christoph Lameter81819f02007-05-06 14:49:36 -0700689 start++;
690 bytes--;
691 }
Christoph Lameter24922682007-07-17 04:03:18 -0700692 return NULL;
693}
694
Marcin Slusarzc4089f92011-06-26 21:39:18 +0200695static u8 *check_bytes(u8 *start, u8 value, unsigned int bytes)
696{
697 u64 value64;
698 unsigned int words, prefix;
699
700 if (bytes <= 16)
701 return check_bytes8(start, value, bytes);
702
703 value64 = value | value << 8 | value << 16 | value << 24;
Akinobu Mitaef62fb32011-08-07 18:30:38 +0900704 value64 = (value64 & 0xffffffff) | value64 << 32;
Marcin Slusarzc4089f92011-06-26 21:39:18 +0200705 prefix = 8 - ((unsigned long)start) % 8;
706
707 if (prefix) {
708 u8 *r = check_bytes8(start, value, prefix);
709 if (r)
710 return r;
711 start += prefix;
712 bytes -= prefix;
713 }
714
715 words = bytes / 8;
716
717 while (words) {
718 if (*(u64 *)start != value64)
719 return check_bytes8(start, value, 8);
720 start += 8;
721 words--;
722 }
723
724 return check_bytes8(start, value, bytes % 8);
725}
726
Christoph Lameter24922682007-07-17 04:03:18 -0700727static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
728 void *from, void *to)
729{
730 slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data);
731 memset(from, data, to - from);
732}
733
734static int check_bytes_and_report(struct kmem_cache *s, struct page *page,
735 u8 *object, char *what,
Pekka Enberg06428782008-01-07 23:20:27 -0800736 u8 *start, unsigned int value, unsigned int bytes)
Christoph Lameter24922682007-07-17 04:03:18 -0700737{
738 u8 *fault;
739 u8 *end;
740
741 fault = check_bytes(start, value, bytes);
742 if (!fault)
743 return 1;
744
745 end = start + bytes;
746 while (end > fault && end[-1] == value)
747 end--;
748
749 slab_bug(s, "%s overwritten", what);
750 printk(KERN_ERR "INFO: 0x%p-0x%p. First byte 0x%x instead of 0x%x\n",
751 fault, end - 1, fault[0], value);
752 print_trailer(s, page, object);
753
754 restore_bytes(s, what, value, fault, end);
755 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700756}
757
Christoph Lameter81819f02007-05-06 14:49:36 -0700758/*
759 * Object layout:
760 *
761 * object address
762 * Bytes of the object to be managed.
763 * If the freepointer may overlay the object then the free
764 * pointer is the first word of the object.
Christoph Lameter672bba32007-05-09 02:32:39 -0700765 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700766 * Poisoning uses 0x6b (POISON_FREE) and the last byte is
767 * 0xa5 (POISON_END)
768 *
769 * object + s->objsize
770 * Padding to reach word boundary. This is also used for Redzoning.
Christoph Lameter672bba32007-05-09 02:32:39 -0700771 * Padding is extended by another word if Redzoning is enabled and
772 * objsize == inuse.
773 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700774 * We fill with 0xbb (RED_INACTIVE) for inactive objects and with
775 * 0xcc (RED_ACTIVE) for objects in use.
776 *
777 * object + s->inuse
Christoph Lameter672bba32007-05-09 02:32:39 -0700778 * Meta data starts here.
779 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700780 * A. Free pointer (if we cannot overwrite object on free)
781 * B. Tracking data for SLAB_STORE_USER
Christoph Lameter672bba32007-05-09 02:32:39 -0700782 * C. Padding to reach required alignment boundary or at mininum
Christoph Lameter6446faa2008-02-15 23:45:26 -0800783 * one word if debugging is on to be able to detect writes
Christoph Lameter672bba32007-05-09 02:32:39 -0700784 * before the word boundary.
785 *
786 * Padding is done using 0x5a (POISON_INUSE)
Christoph Lameter81819f02007-05-06 14:49:36 -0700787 *
788 * object + s->size
Christoph Lameter672bba32007-05-09 02:32:39 -0700789 * Nothing is used beyond s->size.
Christoph Lameter81819f02007-05-06 14:49:36 -0700790 *
Christoph Lameter672bba32007-05-09 02:32:39 -0700791 * If slabcaches are merged then the objsize and inuse boundaries are mostly
792 * ignored. And therefore no slab options that rely on these boundaries
Christoph Lameter81819f02007-05-06 14:49:36 -0700793 * may be used with merged slabcaches.
794 */
795
Christoph Lameter81819f02007-05-06 14:49:36 -0700796static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p)
797{
798 unsigned long off = s->inuse; /* The end of info */
799
800 if (s->offset)
801 /* Freepointer is placed after the object. */
802 off += sizeof(void *);
803
804 if (s->flags & SLAB_STORE_USER)
805 /* We also have user information there */
806 off += 2 * sizeof(struct track);
807
808 if (s->size == off)
809 return 1;
810
Christoph Lameter24922682007-07-17 04:03:18 -0700811 return check_bytes_and_report(s, page, p, "Object padding",
812 p + off, POISON_INUSE, s->size - off);
Christoph Lameter81819f02007-05-06 14:49:36 -0700813}
814
Christoph Lameter39b26462008-04-14 19:11:30 +0300815/* Check the pad bytes at the end of a slab page */
Christoph Lameter81819f02007-05-06 14:49:36 -0700816static int slab_pad_check(struct kmem_cache *s, struct page *page)
817{
Christoph Lameter24922682007-07-17 04:03:18 -0700818 u8 *start;
819 u8 *fault;
820 u8 *end;
821 int length;
822 int remainder;
Christoph Lameter81819f02007-05-06 14:49:36 -0700823
824 if (!(s->flags & SLAB_POISON))
825 return 1;
826
Christoph Lametera973e9d2008-03-01 13:40:44 -0800827 start = page_address(page);
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800828 length = (PAGE_SIZE << compound_order(page)) - s->reserved;
Christoph Lameter39b26462008-04-14 19:11:30 +0300829 end = start + length;
830 remainder = length % s->size;
Christoph Lameter81819f02007-05-06 14:49:36 -0700831 if (!remainder)
832 return 1;
833
Christoph Lameter39b26462008-04-14 19:11:30 +0300834 fault = check_bytes(end - remainder, POISON_INUSE, remainder);
Christoph Lameter24922682007-07-17 04:03:18 -0700835 if (!fault)
836 return 1;
837 while (end > fault && end[-1] == POISON_INUSE)
838 end--;
839
840 slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1);
Christoph Lameter39b26462008-04-14 19:11:30 +0300841 print_section("Padding", end - remainder, remainder);
Christoph Lameter24922682007-07-17 04:03:18 -0700842
Eric Dumazet8a3d2712009-09-03 16:08:06 +0200843 restore_bytes(s, "slab padding", POISON_INUSE, end - remainder, end);
Christoph Lameter24922682007-07-17 04:03:18 -0700844 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700845}
846
847static int check_object(struct kmem_cache *s, struct page *page,
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500848 void *object, u8 val)
Christoph Lameter81819f02007-05-06 14:49:36 -0700849{
850 u8 *p = object;
851 u8 *endobject = object + s->objsize;
852
853 if (s->flags & SLAB_RED_ZONE) {
Christoph Lameter24922682007-07-17 04:03:18 -0700854 if (!check_bytes_and_report(s, page, object, "Redzone",
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500855 endobject, val, s->inuse - s->objsize))
Christoph Lameter81819f02007-05-06 14:49:36 -0700856 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700857 } else {
Ingo Molnar3adbefe2008-02-05 17:57:39 -0800858 if ((s->flags & SLAB_POISON) && s->objsize < s->inuse) {
859 check_bytes_and_report(s, page, p, "Alignment padding",
860 endobject, POISON_INUSE, s->inuse - s->objsize);
861 }
Christoph Lameter81819f02007-05-06 14:49:36 -0700862 }
863
864 if (s->flags & SLAB_POISON) {
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500865 if (val != SLUB_RED_ACTIVE && (s->flags & __OBJECT_POISON) &&
Christoph Lameter24922682007-07-17 04:03:18 -0700866 (!check_bytes_and_report(s, page, p, "Poison", p,
867 POISON_FREE, s->objsize - 1) ||
868 !check_bytes_and_report(s, page, p, "Poison",
Pekka Enberg06428782008-01-07 23:20:27 -0800869 p + s->objsize - 1, POISON_END, 1)))
Christoph Lameter81819f02007-05-06 14:49:36 -0700870 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700871 /*
872 * check_pad_bytes cleans up on its own.
873 */
874 check_pad_bytes(s, page, p);
875 }
876
Christoph Lameterf7cb1932010-09-29 07:15:01 -0500877 if (!s->offset && val == SLUB_RED_ACTIVE)
Christoph Lameter81819f02007-05-06 14:49:36 -0700878 /*
879 * Object and freepointer overlap. Cannot check
880 * freepointer while object is allocated.
881 */
882 return 1;
883
884 /* Check free pointer validity */
885 if (!check_valid_pointer(s, page, get_freepointer(s, p))) {
886 object_err(s, page, p, "Freepointer corrupt");
887 /*
Nick Andrew9f6c708e2008-12-05 14:08:08 +1100888 * No choice but to zap it and thus lose the remainder
Christoph Lameter81819f02007-05-06 14:49:36 -0700889 * of the free objects in this slab. May cause
Christoph Lameter672bba32007-05-09 02:32:39 -0700890 * another error because the object count is now wrong.
Christoph Lameter81819f02007-05-06 14:49:36 -0700891 */
Christoph Lametera973e9d2008-03-01 13:40:44 -0800892 set_freepointer(s, p, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -0700893 return 0;
894 }
895 return 1;
896}
897
898static int check_slab(struct kmem_cache *s, struct page *page)
899{
Christoph Lameter39b26462008-04-14 19:11:30 +0300900 int maxobj;
901
Christoph Lameter81819f02007-05-06 14:49:36 -0700902 VM_BUG_ON(!irqs_disabled());
903
904 if (!PageSlab(page)) {
Christoph Lameter24922682007-07-17 04:03:18 -0700905 slab_err(s, page, "Not a valid slab page");
Christoph Lameter81819f02007-05-06 14:49:36 -0700906 return 0;
907 }
Christoph Lameter39b26462008-04-14 19:11:30 +0300908
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800909 maxobj = order_objects(compound_order(page), s->size, s->reserved);
Christoph Lameter39b26462008-04-14 19:11:30 +0300910 if (page->objects > maxobj) {
911 slab_err(s, page, "objects %u > max %u",
912 s->name, page->objects, maxobj);
913 return 0;
914 }
915 if (page->inuse > page->objects) {
Christoph Lameter24922682007-07-17 04:03:18 -0700916 slab_err(s, page, "inuse %u > max %u",
Christoph Lameter39b26462008-04-14 19:11:30 +0300917 s->name, page->inuse, page->objects);
Christoph Lameter81819f02007-05-06 14:49:36 -0700918 return 0;
919 }
920 /* Slab_pad_check fixes things up after itself */
921 slab_pad_check(s, page);
922 return 1;
923}
924
925/*
Christoph Lameter672bba32007-05-09 02:32:39 -0700926 * Determine if a certain object on a page is on the freelist. Must hold the
927 * slab lock to guarantee that the chains are in a consistent state.
Christoph Lameter81819f02007-05-06 14:49:36 -0700928 */
929static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
930{
931 int nr = 0;
Christoph Lameter881db7f2011-06-01 12:25:53 -0500932 void *fp;
Christoph Lameter81819f02007-05-06 14:49:36 -0700933 void *object = NULL;
Christoph Lameter224a88b2008-04-14 19:11:31 +0300934 unsigned long max_objects;
Christoph Lameter81819f02007-05-06 14:49:36 -0700935
Christoph Lameter881db7f2011-06-01 12:25:53 -0500936 fp = page->freelist;
Christoph Lameter39b26462008-04-14 19:11:30 +0300937 while (fp && nr <= page->objects) {
Christoph Lameter81819f02007-05-06 14:49:36 -0700938 if (fp == search)
939 return 1;
940 if (!check_valid_pointer(s, page, fp)) {
941 if (object) {
942 object_err(s, page, object,
943 "Freechain corrupt");
Christoph Lametera973e9d2008-03-01 13:40:44 -0800944 set_freepointer(s, object, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -0700945 break;
946 } else {
Christoph Lameter24922682007-07-17 04:03:18 -0700947 slab_err(s, page, "Freepointer corrupt");
Christoph Lametera973e9d2008-03-01 13:40:44 -0800948 page->freelist = NULL;
Christoph Lameter39b26462008-04-14 19:11:30 +0300949 page->inuse = page->objects;
Christoph Lameter24922682007-07-17 04:03:18 -0700950 slab_fix(s, "Freelist cleared");
Christoph Lameter81819f02007-05-06 14:49:36 -0700951 return 0;
952 }
953 break;
954 }
955 object = fp;
956 fp = get_freepointer(s, object);
957 nr++;
958 }
959
Lai Jiangshanab9a0f12011-03-10 15:21:48 +0800960 max_objects = order_objects(compound_order(page), s->size, s->reserved);
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400961 if (max_objects > MAX_OBJS_PER_PAGE)
962 max_objects = MAX_OBJS_PER_PAGE;
Christoph Lameter224a88b2008-04-14 19:11:31 +0300963
964 if (page->objects != max_objects) {
965 slab_err(s, page, "Wrong number of objects. Found %d but "
966 "should be %d", page->objects, max_objects);
967 page->objects = max_objects;
968 slab_fix(s, "Number of objects adjusted.");
969 }
Christoph Lameter39b26462008-04-14 19:11:30 +0300970 if (page->inuse != page->objects - nr) {
Christoph Lameter70d71222007-05-06 14:49:47 -0700971 slab_err(s, page, "Wrong object count. Counter is %d but "
Christoph Lameter39b26462008-04-14 19:11:30 +0300972 "counted were %d", page->inuse, page->objects - nr);
973 page->inuse = page->objects - nr;
Christoph Lameter24922682007-07-17 04:03:18 -0700974 slab_fix(s, "Object count adjusted.");
Christoph Lameter81819f02007-05-06 14:49:36 -0700975 }
976 return search == NULL;
977}
978
Christoph Lameter0121c6192008-04-29 16:11:12 -0700979static void trace(struct kmem_cache *s, struct page *page, void *object,
980 int alloc)
Christoph Lameter3ec09742007-05-16 22:11:00 -0700981{
982 if (s->flags & SLAB_TRACE) {
983 printk(KERN_INFO "TRACE %s %s 0x%p inuse=%d fp=0x%p\n",
984 s->name,
985 alloc ? "alloc" : "free",
986 object, page->inuse,
987 page->freelist);
988
989 if (!alloc)
990 print_section("Object", (void *)object, s->objsize);
991
992 dump_stack();
993 }
994}
995
Christoph Lameter643b1132007-05-06 14:49:42 -0700996/*
Christoph Lameterc016b0b2010-08-20 12:37:16 -0500997 * Hooks for other subsystems that check memory allocations. In a typical
998 * production configuration these hooks all should produce no code at all.
999 */
1000static inline int slab_pre_alloc_hook(struct kmem_cache *s, gfp_t flags)
1001{
Christoph Lameterc1d50832010-08-20 12:37:17 -05001002 flags &= gfp_allowed_mask;
Christoph Lameterc016b0b2010-08-20 12:37:16 -05001003 lockdep_trace_alloc(flags);
1004 might_sleep_if(flags & __GFP_WAIT);
1005
1006 return should_failslab(s->objsize, flags, s->flags);
1007}
1008
1009static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags, void *object)
1010{
Christoph Lameterc1d50832010-08-20 12:37:17 -05001011 flags &= gfp_allowed_mask;
Eric Dumazetb3d41882011-02-14 18:35:22 +01001012 kmemcheck_slab_alloc(s, flags, object, slab_ksize(s));
Christoph Lameterc016b0b2010-08-20 12:37:16 -05001013 kmemleak_alloc_recursive(object, s->objsize, 1, s->flags, flags);
1014}
1015
1016static inline void slab_free_hook(struct kmem_cache *s, void *x)
1017{
1018 kmemleak_free_recursive(x, s->flags);
Christoph Lameterc016b0b2010-08-20 12:37:16 -05001019
Christoph Lameterd3f661d2011-02-25 11:38:52 -06001020 /*
1021 * Trouble is that we may no longer disable interupts in the fast path
1022 * So in order to make the debug calls that expect irqs to be
1023 * disabled we need to disable interrupts temporarily.
1024 */
1025#if defined(CONFIG_KMEMCHECK) || defined(CONFIG_LOCKDEP)
1026 {
1027 unsigned long flags;
1028
1029 local_irq_save(flags);
1030 kmemcheck_slab_free(s, x, s->objsize);
1031 debug_check_no_locks_freed(x, s->objsize);
Christoph Lameterd3f661d2011-02-25 11:38:52 -06001032 local_irq_restore(flags);
1033 }
1034#endif
Thomas Gleixnerf9b615d2011-03-24 21:26:46 +02001035 if (!(s->flags & SLAB_DEBUG_OBJECTS))
1036 debug_check_no_obj_freed(x, s->objsize);
Christoph Lameterc016b0b2010-08-20 12:37:16 -05001037}
1038
1039/*
Christoph Lameter672bba32007-05-09 02:32:39 -07001040 * Tracking of fully allocated slabs for debugging purposes.
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05001041 *
1042 * list_lock must be held.
Christoph Lameter643b1132007-05-06 14:49:42 -07001043 */
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05001044static void add_full(struct kmem_cache *s,
1045 struct kmem_cache_node *n, struct page *page)
Christoph Lameter643b1132007-05-06 14:49:42 -07001046{
Christoph Lameter643b1132007-05-06 14:49:42 -07001047 if (!(s->flags & SLAB_STORE_USER))
1048 return;
1049
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05001050 list_add(&page->lru, &n->full);
1051}
Christoph Lameter643b1132007-05-06 14:49:42 -07001052
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05001053/*
1054 * list_lock must be held.
1055 */
1056static void remove_full(struct kmem_cache *s, struct page *page)
1057{
1058 if (!(s->flags & SLAB_STORE_USER))
1059 return;
1060
Christoph Lameter643b1132007-05-06 14:49:42 -07001061 list_del(&page->lru);
Christoph Lameter643b1132007-05-06 14:49:42 -07001062}
1063
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001064/* Tracking of the number of slabs for debugging purposes */
1065static inline unsigned long slabs_node(struct kmem_cache *s, int node)
1066{
1067 struct kmem_cache_node *n = get_node(s, node);
1068
1069 return atomic_long_read(&n->nr_slabs);
1070}
1071
Alexander Beregalov26c02cf2009-06-11 14:08:48 +04001072static inline unsigned long node_nr_slabs(struct kmem_cache_node *n)
1073{
1074 return atomic_long_read(&n->nr_slabs);
1075}
1076
Christoph Lameter205ab992008-04-14 19:11:40 +03001077static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects)
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001078{
1079 struct kmem_cache_node *n = get_node(s, node);
1080
1081 /*
1082 * May be called early in order to allocate a slab for the
1083 * kmem_cache_node structure. Solve the chicken-egg
1084 * dilemma by deferring the increment of the count during
1085 * bootstrap (see early_kmem_cache_node_alloc).
1086 */
Christoph Lameter7340cc82010-09-28 08:10:26 -05001087 if (n) {
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001088 atomic_long_inc(&n->nr_slabs);
Christoph Lameter205ab992008-04-14 19:11:40 +03001089 atomic_long_add(objects, &n->total_objects);
1090 }
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001091}
Christoph Lameter205ab992008-04-14 19:11:40 +03001092static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects)
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001093{
1094 struct kmem_cache_node *n = get_node(s, node);
1095
1096 atomic_long_dec(&n->nr_slabs);
Christoph Lameter205ab992008-04-14 19:11:40 +03001097 atomic_long_sub(objects, &n->total_objects);
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001098}
1099
1100/* Object debug checks for alloc/free paths */
Christoph Lameter3ec09742007-05-16 22:11:00 -07001101static void setup_object_debug(struct kmem_cache *s, struct page *page,
1102 void *object)
1103{
1104 if (!(s->flags & (SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON)))
1105 return;
1106
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001107 init_object(s, object, SLUB_RED_INACTIVE);
Christoph Lameter3ec09742007-05-16 22:11:00 -07001108 init_tracking(s, object);
1109}
1110
Christoph Lameter15370662010-08-20 12:37:12 -05001111static noinline int alloc_debug_processing(struct kmem_cache *s, struct page *page,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001112 void *object, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -07001113{
1114 if (!check_slab(s, page))
1115 goto bad;
1116
Christoph Lameter81819f02007-05-06 14:49:36 -07001117 if (!check_valid_pointer(s, page, object)) {
1118 object_err(s, page, object, "Freelist Pointer check fails");
Christoph Lameter70d71222007-05-06 14:49:47 -07001119 goto bad;
Christoph Lameter81819f02007-05-06 14:49:36 -07001120 }
1121
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001122 if (!check_object(s, page, object, SLUB_RED_INACTIVE))
Christoph Lameter81819f02007-05-06 14:49:36 -07001123 goto bad;
Christoph Lameter81819f02007-05-06 14:49:36 -07001124
Christoph Lameter3ec09742007-05-16 22:11:00 -07001125 /* Success perform special debug activities for allocs */
1126 if (s->flags & SLAB_STORE_USER)
1127 set_track(s, object, TRACK_ALLOC, addr);
1128 trace(s, page, object, 1);
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001129 init_object(s, object, SLUB_RED_ACTIVE);
Christoph Lameter81819f02007-05-06 14:49:36 -07001130 return 1;
Christoph Lameter3ec09742007-05-16 22:11:00 -07001131
Christoph Lameter81819f02007-05-06 14:49:36 -07001132bad:
1133 if (PageSlab(page)) {
1134 /*
1135 * If this is a slab page then lets do the best we can
1136 * to avoid issues in the future. Marking all objects
Christoph Lameter672bba32007-05-09 02:32:39 -07001137 * as used avoids touching the remaining objects.
Christoph Lameter81819f02007-05-06 14:49:36 -07001138 */
Christoph Lameter24922682007-07-17 04:03:18 -07001139 slab_fix(s, "Marking all objects used");
Christoph Lameter39b26462008-04-14 19:11:30 +03001140 page->inuse = page->objects;
Christoph Lametera973e9d2008-03-01 13:40:44 -08001141 page->freelist = NULL;
Christoph Lameter81819f02007-05-06 14:49:36 -07001142 }
1143 return 0;
1144}
1145
Christoph Lameter15370662010-08-20 12:37:12 -05001146static noinline int free_debug_processing(struct kmem_cache *s,
1147 struct page *page, void *object, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -07001148{
Christoph Lameter5c2e4bb2011-06-01 12:25:54 -05001149 unsigned long flags;
1150 int rc = 0;
1151
1152 local_irq_save(flags);
Christoph Lameter881db7f2011-06-01 12:25:53 -05001153 slab_lock(page);
1154
Christoph Lameter81819f02007-05-06 14:49:36 -07001155 if (!check_slab(s, page))
1156 goto fail;
1157
1158 if (!check_valid_pointer(s, page, object)) {
Christoph Lameter70d71222007-05-06 14:49:47 -07001159 slab_err(s, page, "Invalid object pointer 0x%p", object);
Christoph Lameter81819f02007-05-06 14:49:36 -07001160 goto fail;
1161 }
1162
1163 if (on_freelist(s, page, object)) {
Christoph Lameter24922682007-07-17 04:03:18 -07001164 object_err(s, page, object, "Object already free");
Christoph Lameter81819f02007-05-06 14:49:36 -07001165 goto fail;
1166 }
1167
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001168 if (!check_object(s, page, object, SLUB_RED_ACTIVE))
Christoph Lameter5c2e4bb2011-06-01 12:25:54 -05001169 goto out;
Christoph Lameter81819f02007-05-06 14:49:36 -07001170
1171 if (unlikely(s != page->slab)) {
Ingo Molnar3adbefe2008-02-05 17:57:39 -08001172 if (!PageSlab(page)) {
Christoph Lameter70d71222007-05-06 14:49:47 -07001173 slab_err(s, page, "Attempt to free object(0x%p) "
1174 "outside of slab", object);
Ingo Molnar3adbefe2008-02-05 17:57:39 -08001175 } else if (!page->slab) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001176 printk(KERN_ERR
Christoph Lameter70d71222007-05-06 14:49:47 -07001177 "SLUB <none>: no slab for object 0x%p.\n",
Christoph Lameter81819f02007-05-06 14:49:36 -07001178 object);
Christoph Lameter70d71222007-05-06 14:49:47 -07001179 dump_stack();
Pekka Enberg06428782008-01-07 23:20:27 -08001180 } else
Christoph Lameter24922682007-07-17 04:03:18 -07001181 object_err(s, page, object,
1182 "page slab pointer corrupt.");
Christoph Lameter81819f02007-05-06 14:49:36 -07001183 goto fail;
1184 }
Christoph Lameter3ec09742007-05-16 22:11:00 -07001185
Christoph Lameter3ec09742007-05-16 22:11:00 -07001186 if (s->flags & SLAB_STORE_USER)
1187 set_track(s, object, TRACK_FREE, addr);
1188 trace(s, page, object, 0);
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001189 init_object(s, object, SLUB_RED_INACTIVE);
Christoph Lameter5c2e4bb2011-06-01 12:25:54 -05001190 rc = 1;
1191out:
Christoph Lameter881db7f2011-06-01 12:25:53 -05001192 slab_unlock(page);
Christoph Lameter5c2e4bb2011-06-01 12:25:54 -05001193 local_irq_restore(flags);
1194 return rc;
Christoph Lameter3ec09742007-05-16 22:11:00 -07001195
Christoph Lameter81819f02007-05-06 14:49:36 -07001196fail:
Christoph Lameter24922682007-07-17 04:03:18 -07001197 slab_fix(s, "Object at 0x%p not freed", object);
Christoph Lameter5c2e4bb2011-06-01 12:25:54 -05001198 goto out;
Christoph Lameter81819f02007-05-06 14:49:36 -07001199}
1200
Christoph Lameter41ecc552007-05-09 02:32:44 -07001201static int __init setup_slub_debug(char *str)
1202{
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001203 slub_debug = DEBUG_DEFAULT_FLAGS;
1204 if (*str++ != '=' || !*str)
1205 /*
1206 * No options specified. Switch on full debugging.
1207 */
1208 goto out;
Christoph Lameter41ecc552007-05-09 02:32:44 -07001209
1210 if (*str == ',')
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001211 /*
1212 * No options but restriction on slabs. This means full
1213 * debugging for slabs matching a pattern.
1214 */
1215 goto check_slabs;
1216
David Rientjesfa5ec8a2009-07-07 00:14:14 -07001217 if (tolower(*str) == 'o') {
1218 /*
1219 * Avoid enabling debugging on caches if its minimum order
1220 * would increase as a result.
1221 */
1222 disable_higher_order_debug = 1;
1223 goto out;
1224 }
1225
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001226 slub_debug = 0;
1227 if (*str == '-')
1228 /*
1229 * Switch off all debugging measures.
1230 */
1231 goto out;
1232
1233 /*
1234 * Determine which debug features should be switched on
1235 */
Pekka Enberg06428782008-01-07 23:20:27 -08001236 for (; *str && *str != ','; str++) {
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001237 switch (tolower(*str)) {
1238 case 'f':
1239 slub_debug |= SLAB_DEBUG_FREE;
1240 break;
1241 case 'z':
1242 slub_debug |= SLAB_RED_ZONE;
1243 break;
1244 case 'p':
1245 slub_debug |= SLAB_POISON;
1246 break;
1247 case 'u':
1248 slub_debug |= SLAB_STORE_USER;
1249 break;
1250 case 't':
1251 slub_debug |= SLAB_TRACE;
1252 break;
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +03001253 case 'a':
1254 slub_debug |= SLAB_FAILSLAB;
1255 break;
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001256 default:
1257 printk(KERN_ERR "slub_debug option '%c' "
Pekka Enberg06428782008-01-07 23:20:27 -08001258 "unknown. skipped\n", *str);
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001259 }
1260 }
1261
1262check_slabs:
1263 if (*str == ',')
Christoph Lameter41ecc552007-05-09 02:32:44 -07001264 slub_debug_slabs = str + 1;
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001265out:
Christoph Lameter41ecc552007-05-09 02:32:44 -07001266 return 1;
1267}
1268
1269__setup("slub_debug", setup_slub_debug);
1270
Christoph Lameterba0268a2007-09-11 15:24:11 -07001271static unsigned long kmem_cache_flags(unsigned long objsize,
1272 unsigned long flags, const char *name,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001273 void (*ctor)(void *))
Christoph Lameter41ecc552007-05-09 02:32:44 -07001274{
1275 /*
Christoph Lametere1533622008-02-15 23:45:24 -08001276 * Enable debugging if selected on the kernel commandline.
Christoph Lameter41ecc552007-05-09 02:32:44 -07001277 */
Christoph Lametere1533622008-02-15 23:45:24 -08001278 if (slub_debug && (!slub_debug_slabs ||
David Rientjes3de47212009-07-27 18:30:35 -07001279 !strncmp(slub_debug_slabs, name, strlen(slub_debug_slabs))))
1280 flags |= slub_debug;
Christoph Lameterba0268a2007-09-11 15:24:11 -07001281
1282 return flags;
Christoph Lameter41ecc552007-05-09 02:32:44 -07001283}
1284#else
Christoph Lameter3ec09742007-05-16 22:11:00 -07001285static inline void setup_object_debug(struct kmem_cache *s,
1286 struct page *page, void *object) {}
Christoph Lameter41ecc552007-05-09 02:32:44 -07001287
Christoph Lameter3ec09742007-05-16 22:11:00 -07001288static inline int alloc_debug_processing(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001289 struct page *page, void *object, unsigned long addr) { return 0; }
Christoph Lameter41ecc552007-05-09 02:32:44 -07001290
Christoph Lameter3ec09742007-05-16 22:11:00 -07001291static inline int free_debug_processing(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001292 struct page *page, void *object, unsigned long addr) { return 0; }
Christoph Lameter41ecc552007-05-09 02:32:44 -07001293
Christoph Lameter41ecc552007-05-09 02:32:44 -07001294static inline int slab_pad_check(struct kmem_cache *s, struct page *page)
1295 { return 1; }
1296static inline int check_object(struct kmem_cache *s, struct page *page,
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001297 void *object, u8 val) { return 1; }
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05001298static inline void add_full(struct kmem_cache *s, struct kmem_cache_node *n,
1299 struct page *page) {}
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001300static inline void remove_full(struct kmem_cache *s, struct page *page) {}
Christoph Lameterba0268a2007-09-11 15:24:11 -07001301static inline unsigned long kmem_cache_flags(unsigned long objsize,
1302 unsigned long flags, const char *name,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001303 void (*ctor)(void *))
Christoph Lameterba0268a2007-09-11 15:24:11 -07001304{
1305 return flags;
1306}
Christoph Lameter41ecc552007-05-09 02:32:44 -07001307#define slub_debug 0
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001308
Ingo Molnarfdaa45e2009-09-15 11:00:26 +02001309#define disable_higher_order_debug 0
1310
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001311static inline unsigned long slabs_node(struct kmem_cache *s, int node)
1312 { return 0; }
Alexander Beregalov26c02cf2009-06-11 14:08:48 +04001313static inline unsigned long node_nr_slabs(struct kmem_cache_node *n)
1314 { return 0; }
Christoph Lameter205ab992008-04-14 19:11:40 +03001315static inline void inc_slabs_node(struct kmem_cache *s, int node,
1316 int objects) {}
1317static inline void dec_slabs_node(struct kmem_cache *s, int node,
1318 int objects) {}
Christoph Lameter7d550c52010-08-25 14:07:16 -05001319
1320static inline int slab_pre_alloc_hook(struct kmem_cache *s, gfp_t flags)
1321 { return 0; }
1322
1323static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
1324 void *object) {}
1325
1326static inline void slab_free_hook(struct kmem_cache *s, void *x) {}
1327
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05001328#endif /* CONFIG_SLUB_DEBUG */
Christoph Lameter205ab992008-04-14 19:11:40 +03001329
Christoph Lameter81819f02007-05-06 14:49:36 -07001330/*
1331 * Slab allocation and freeing
1332 */
Christoph Lameter65c33762008-04-14 19:11:40 +03001333static inline struct page *alloc_slab_page(gfp_t flags, int node,
1334 struct kmem_cache_order_objects oo)
1335{
1336 int order = oo_order(oo);
1337
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001338 flags |= __GFP_NOTRACK;
1339
Christoph Lameter2154a332010-07-09 14:07:10 -05001340 if (node == NUMA_NO_NODE)
Christoph Lameter65c33762008-04-14 19:11:40 +03001341 return alloc_pages(flags, order);
1342 else
Minchan Kim6b65aaf2010-04-14 23:58:36 +09001343 return alloc_pages_exact_node(node, flags, order);
Christoph Lameter65c33762008-04-14 19:11:40 +03001344}
1345
Christoph Lameter81819f02007-05-06 14:49:36 -07001346static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
1347{
Pekka Enberg06428782008-01-07 23:20:27 -08001348 struct page *page;
Christoph Lameter834f3d12008-04-14 19:11:31 +03001349 struct kmem_cache_order_objects oo = s->oo;
Pekka Enbergba522702009-06-24 21:59:51 +03001350 gfp_t alloc_gfp;
Christoph Lameter81819f02007-05-06 14:49:36 -07001351
Christoph Lameter7e0528d2011-06-01 12:25:44 -05001352 flags &= gfp_allowed_mask;
1353
1354 if (flags & __GFP_WAIT)
1355 local_irq_enable();
1356
Christoph Lameterb7a49f02008-02-14 14:21:32 -08001357 flags |= s->allocflags;
Mel Gormane12ba742007-10-16 01:25:52 -07001358
Pekka Enbergba522702009-06-24 21:59:51 +03001359 /*
1360 * Let the initial higher-order allocation fail under memory pressure
1361 * so we fall-back to the minimum order allocation.
1362 */
1363 alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL;
1364
1365 page = alloc_slab_page(alloc_gfp, node, oo);
Christoph Lameter65c33762008-04-14 19:11:40 +03001366 if (unlikely(!page)) {
1367 oo = s->min;
1368 /*
1369 * Allocation may have failed due to fragmentation.
1370 * Try a lower order alloc if possible
1371 */
1372 page = alloc_slab_page(flags, node, oo);
Christoph Lameter81819f02007-05-06 14:49:36 -07001373
Christoph Lameter7e0528d2011-06-01 12:25:44 -05001374 if (page)
1375 stat(s, ORDER_FALLBACK);
Christoph Lameter65c33762008-04-14 19:11:40 +03001376 }
Vegard Nossum5a896d92008-04-04 00:54:48 +02001377
Christoph Lameter7e0528d2011-06-01 12:25:44 -05001378 if (flags & __GFP_WAIT)
1379 local_irq_disable();
1380
1381 if (!page)
1382 return NULL;
1383
Vegard Nossum5a896d92008-04-04 00:54:48 +02001384 if (kmemcheck_enabled
Amerigo Wang5086c389c2009-08-19 21:44:13 +03001385 && !(s->flags & (SLAB_NOTRACK | DEBUG_DEFAULT_FLAGS))) {
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001386 int pages = 1 << oo_order(oo);
1387
1388 kmemcheck_alloc_shadow(page, oo_order(oo), flags, node);
1389
1390 /*
1391 * Objects from caches that have a constructor don't get
1392 * cleared when they're allocated, so we need to do it here.
1393 */
1394 if (s->ctor)
1395 kmemcheck_mark_uninitialized_pages(page, pages);
1396 else
1397 kmemcheck_mark_unallocated_pages(page, pages);
Vegard Nossum5a896d92008-04-04 00:54:48 +02001398 }
1399
Christoph Lameter834f3d12008-04-14 19:11:31 +03001400 page->objects = oo_objects(oo);
Christoph Lameter81819f02007-05-06 14:49:36 -07001401 mod_zone_page_state(page_zone(page),
1402 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
1403 NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
Christoph Lameter65c33762008-04-14 19:11:40 +03001404 1 << oo_order(oo));
Christoph Lameter81819f02007-05-06 14:49:36 -07001405
1406 return page;
1407}
1408
1409static void setup_object(struct kmem_cache *s, struct page *page,
1410 void *object)
1411{
Christoph Lameter3ec09742007-05-16 22:11:00 -07001412 setup_object_debug(s, page, object);
Christoph Lameter4f104932007-05-06 14:50:17 -07001413 if (unlikely(s->ctor))
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001414 s->ctor(object);
Christoph Lameter81819f02007-05-06 14:49:36 -07001415}
1416
1417static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
1418{
1419 struct page *page;
Christoph Lameter81819f02007-05-06 14:49:36 -07001420 void *start;
Christoph Lameter81819f02007-05-06 14:49:36 -07001421 void *last;
1422 void *p;
1423
Christoph Lameter6cb06222007-10-16 01:25:41 -07001424 BUG_ON(flags & GFP_SLAB_BUG_MASK);
Christoph Lameter81819f02007-05-06 14:49:36 -07001425
Christoph Lameter6cb06222007-10-16 01:25:41 -07001426 page = allocate_slab(s,
1427 flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node);
Christoph Lameter81819f02007-05-06 14:49:36 -07001428 if (!page)
1429 goto out;
1430
Christoph Lameter205ab992008-04-14 19:11:40 +03001431 inc_slabs_node(s, page_to_nid(page), page->objects);
Christoph Lameter81819f02007-05-06 14:49:36 -07001432 page->slab = s;
1433 page->flags |= 1 << PG_slab;
Christoph Lameter81819f02007-05-06 14:49:36 -07001434
1435 start = page_address(page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001436
1437 if (unlikely(s->flags & SLAB_POISON))
Christoph Lameter834f3d12008-04-14 19:11:31 +03001438 memset(start, POISON_INUSE, PAGE_SIZE << compound_order(page));
Christoph Lameter81819f02007-05-06 14:49:36 -07001439
1440 last = start;
Christoph Lameter224a88b2008-04-14 19:11:31 +03001441 for_each_object(p, s, start, page->objects) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001442 setup_object(s, page, last);
1443 set_freepointer(s, last, p);
1444 last = p;
1445 }
1446 setup_object(s, page, last);
Christoph Lametera973e9d2008-03-01 13:40:44 -08001447 set_freepointer(s, last, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -07001448
1449 page->freelist = start;
Christoph Lametere6e82ea2011-08-09 16:12:24 -05001450 page->inuse = page->objects;
Christoph Lameter8cb0a502011-06-01 12:25:46 -05001451 page->frozen = 1;
Christoph Lameter81819f02007-05-06 14:49:36 -07001452out:
Christoph Lameter81819f02007-05-06 14:49:36 -07001453 return page;
1454}
1455
1456static void __free_slab(struct kmem_cache *s, struct page *page)
1457{
Christoph Lameter834f3d12008-04-14 19:11:31 +03001458 int order = compound_order(page);
1459 int pages = 1 << order;
Christoph Lameter81819f02007-05-06 14:49:36 -07001460
Christoph Lameteraf537b02010-07-09 14:07:14 -05001461 if (kmem_cache_debug(s)) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001462 void *p;
1463
1464 slab_pad_check(s, page);
Christoph Lameter224a88b2008-04-14 19:11:31 +03001465 for_each_object(p, s, page_address(page),
1466 page->objects)
Christoph Lameterf7cb1932010-09-29 07:15:01 -05001467 check_object(s, page, p, SLUB_RED_INACTIVE);
Christoph Lameter81819f02007-05-06 14:49:36 -07001468 }
1469
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001470 kmemcheck_free_shadow(page, compound_order(page));
Vegard Nossum5a896d92008-04-04 00:54:48 +02001471
Christoph Lameter81819f02007-05-06 14:49:36 -07001472 mod_zone_page_state(page_zone(page),
1473 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
1474 NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
Pekka Enberg06428782008-01-07 23:20:27 -08001475 -pages);
Christoph Lameter81819f02007-05-06 14:49:36 -07001476
Christoph Lameter49bd5222008-04-14 18:52:18 +03001477 __ClearPageSlab(page);
1478 reset_page_mapcount(page);
Nick Piggin1eb5ac62009-05-05 19:13:44 +10001479 if (current->reclaim_state)
1480 current->reclaim_state->reclaimed_slab += pages;
Christoph Lameter834f3d12008-04-14 19:11:31 +03001481 __free_pages(page, order);
Christoph Lameter81819f02007-05-06 14:49:36 -07001482}
1483
Lai Jiangshanda9a6382011-03-10 15:22:00 +08001484#define need_reserve_slab_rcu \
1485 (sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head))
1486
Christoph Lameter81819f02007-05-06 14:49:36 -07001487static void rcu_free_slab(struct rcu_head *h)
1488{
1489 struct page *page;
1490
Lai Jiangshanda9a6382011-03-10 15:22:00 +08001491 if (need_reserve_slab_rcu)
1492 page = virt_to_head_page(h);
1493 else
1494 page = container_of((struct list_head *)h, struct page, lru);
1495
Christoph Lameter81819f02007-05-06 14:49:36 -07001496 __free_slab(page->slab, page);
1497}
1498
1499static void free_slab(struct kmem_cache *s, struct page *page)
1500{
1501 if (unlikely(s->flags & SLAB_DESTROY_BY_RCU)) {
Lai Jiangshanda9a6382011-03-10 15:22:00 +08001502 struct rcu_head *head;
1503
1504 if (need_reserve_slab_rcu) {
1505 int order = compound_order(page);
1506 int offset = (PAGE_SIZE << order) - s->reserved;
1507
1508 VM_BUG_ON(s->reserved != sizeof(*head));
1509 head = page_address(page) + offset;
1510 } else {
1511 /*
1512 * RCU free overloads the RCU head over the LRU
1513 */
1514 head = (void *)&page->lru;
1515 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001516
1517 call_rcu(head, rcu_free_slab);
1518 } else
1519 __free_slab(s, page);
1520}
1521
1522static void discard_slab(struct kmem_cache *s, struct page *page)
1523{
Christoph Lameter205ab992008-04-14 19:11:40 +03001524 dec_slabs_node(s, page_to_nid(page), page->objects);
Christoph Lameter81819f02007-05-06 14:49:36 -07001525 free_slab(s, page);
1526}
1527
1528/*
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05001529 * Management of partially allocated slabs.
1530 *
1531 * list_lock must be held.
Christoph Lameter81819f02007-05-06 14:49:36 -07001532 */
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05001533static inline void add_partial(struct kmem_cache_node *n,
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001534 struct page *page, int tail)
Christoph Lameter81819f02007-05-06 14:49:36 -07001535{
Christoph Lametere95eed52007-05-06 14:49:44 -07001536 n->nr_partial++;
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001537 if (tail)
1538 list_add_tail(&page->lru, &n->partial);
1539 else
1540 list_add(&page->lru, &n->partial);
Christoph Lameter81819f02007-05-06 14:49:36 -07001541}
1542
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05001543/*
1544 * list_lock must be held.
1545 */
1546static inline void remove_partial(struct kmem_cache_node *n,
Christoph Lameter62e346a2010-09-28 08:10:28 -05001547 struct page *page)
1548{
1549 list_del(&page->lru);
1550 n->nr_partial--;
1551}
1552
Christoph Lameter81819f02007-05-06 14:49:36 -07001553/*
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05001554 * Lock slab, remove from the partial list and put the object into the
1555 * per cpu freelist.
Christoph Lameter81819f02007-05-06 14:49:36 -07001556 *
Christoph Lameter497b66f2011-08-09 16:12:26 -05001557 * Returns a list of objects or NULL if it fails.
1558 *
Christoph Lameter672bba32007-05-09 02:32:39 -07001559 * Must hold list_lock.
Christoph Lameter81819f02007-05-06 14:49:36 -07001560 */
Christoph Lameter497b66f2011-08-09 16:12:26 -05001561static inline void *acquire_slab(struct kmem_cache *s,
Christoph Lameteracd19fd2011-08-09 16:12:25 -05001562 struct kmem_cache_node *n, struct page *page,
Christoph Lameter49e22582011-08-09 16:12:27 -05001563 int mode)
Christoph Lameter81819f02007-05-06 14:49:36 -07001564{
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001565 void *freelist;
1566 unsigned long counters;
1567 struct page new;
1568
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001569 /*
1570 * Zap the freelist and set the frozen bit.
1571 * The old freelist is the list of objects for the
1572 * per cpu allocation list.
1573 */
1574 do {
1575 freelist = page->freelist;
1576 counters = page->counters;
1577 new.counters = counters;
Christoph Lameter49e22582011-08-09 16:12:27 -05001578 if (mode)
1579 new.inuse = page->objects;
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001580
1581 VM_BUG_ON(new.frozen);
1582 new.frozen = 1;
1583
Christoph Lameter1d071712011-07-14 12:49:12 -05001584 } while (!__cmpxchg_double_slab(s, page,
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001585 freelist, counters,
1586 NULL, new.counters,
1587 "lock and freeze"));
1588
1589 remove_partial(n, page);
Christoph Lameter49e22582011-08-09 16:12:27 -05001590 return freelist;
Christoph Lameter81819f02007-05-06 14:49:36 -07001591}
1592
Christoph Lameter49e22582011-08-09 16:12:27 -05001593static int put_cpu_partial(struct kmem_cache *s, struct page *page, int drain);
1594
Christoph Lameter81819f02007-05-06 14:49:36 -07001595/*
Christoph Lameter672bba32007-05-09 02:32:39 -07001596 * Try to allocate a partial slab from a specific node.
Christoph Lameter81819f02007-05-06 14:49:36 -07001597 */
Christoph Lameter497b66f2011-08-09 16:12:26 -05001598static void *get_partial_node(struct kmem_cache *s,
Christoph Lameteracd19fd2011-08-09 16:12:25 -05001599 struct kmem_cache_node *n, struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07001600{
Christoph Lameter49e22582011-08-09 16:12:27 -05001601 struct page *page, *page2;
1602 void *object = NULL;
Christoph Lameter81819f02007-05-06 14:49:36 -07001603
1604 /*
1605 * Racy check. If we mistakenly see no partial slabs then we
1606 * just allocate an empty slab. If we mistakenly try to get a
Christoph Lameter672bba32007-05-09 02:32:39 -07001607 * partial slab and there is none available then get_partials()
1608 * will return NULL.
Christoph Lameter81819f02007-05-06 14:49:36 -07001609 */
1610 if (!n || !n->nr_partial)
1611 return NULL;
1612
1613 spin_lock(&n->list_lock);
Christoph Lameter49e22582011-08-09 16:12:27 -05001614 list_for_each_entry_safe(page, page2, &n->partial, lru) {
Alex,Shi12d79632011-09-07 10:26:36 +08001615 void *t = acquire_slab(s, n, page, object == NULL);
Christoph Lameter49e22582011-08-09 16:12:27 -05001616 int available;
1617
1618 if (!t)
1619 break;
1620
Alex,Shi12d79632011-09-07 10:26:36 +08001621 if (!object) {
Christoph Lameter49e22582011-08-09 16:12:27 -05001622 c->page = page;
1623 c->node = page_to_nid(page);
1624 stat(s, ALLOC_FROM_PARTIAL);
Christoph Lameter49e22582011-08-09 16:12:27 -05001625 object = t;
1626 available = page->objects - page->inuse;
1627 } else {
1628 page->freelist = t;
1629 available = put_cpu_partial(s, page, 0);
1630 }
1631 if (kmem_cache_debug(s) || available > s->cpu_partial / 2)
1632 break;
1633
Christoph Lameter497b66f2011-08-09 16:12:26 -05001634 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001635 spin_unlock(&n->list_lock);
Christoph Lameter497b66f2011-08-09 16:12:26 -05001636 return object;
Christoph Lameter81819f02007-05-06 14:49:36 -07001637}
1638
1639/*
Christoph Lameter672bba32007-05-09 02:32:39 -07001640 * Get a page from somewhere. Search in increasing NUMA distances.
Christoph Lameter81819f02007-05-06 14:49:36 -07001641 */
Christoph Lameteracd19fd2011-08-09 16:12:25 -05001642static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags,
1643 struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07001644{
1645#ifdef CONFIG_NUMA
1646 struct zonelist *zonelist;
Mel Gormandd1a2392008-04-28 02:12:17 -07001647 struct zoneref *z;
Mel Gorman54a6eb52008-04-28 02:12:16 -07001648 struct zone *zone;
1649 enum zone_type high_zoneidx = gfp_zone(flags);
Christoph Lameter497b66f2011-08-09 16:12:26 -05001650 void *object;
Christoph Lameter81819f02007-05-06 14:49:36 -07001651
1652 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07001653 * The defrag ratio allows a configuration of the tradeoffs between
1654 * inter node defragmentation and node local allocations. A lower
1655 * defrag_ratio increases the tendency to do local allocations
1656 * instead of attempting to obtain partial slabs from other nodes.
Christoph Lameter81819f02007-05-06 14:49:36 -07001657 *
Christoph Lameter672bba32007-05-09 02:32:39 -07001658 * If the defrag_ratio is set to 0 then kmalloc() always
1659 * returns node local objects. If the ratio is higher then kmalloc()
1660 * may return off node objects because partial slabs are obtained
1661 * from other nodes and filled up.
Christoph Lameter81819f02007-05-06 14:49:36 -07001662 *
Christoph Lameter6446faa2008-02-15 23:45:26 -08001663 * If /sys/kernel/slab/xx/defrag_ratio is set to 100 (which makes
Christoph Lameter672bba32007-05-09 02:32:39 -07001664 * defrag_ratio = 1000) then every (well almost) allocation will
1665 * first attempt to defrag slab caches on other nodes. This means
1666 * scanning over all nodes to look for partial slabs which may be
1667 * expensive if we do it every time we are trying to find a slab
1668 * with available objects.
Christoph Lameter81819f02007-05-06 14:49:36 -07001669 */
Christoph Lameter98246012008-01-07 23:20:26 -08001670 if (!s->remote_node_defrag_ratio ||
1671 get_cycles() % 1024 > s->remote_node_defrag_ratio)
Christoph Lameter81819f02007-05-06 14:49:36 -07001672 return NULL;
1673
Miao Xiec0ff7452010-05-24 14:32:08 -07001674 get_mems_allowed();
Mel Gorman0e884602008-04-28 02:12:14 -07001675 zonelist = node_zonelist(slab_node(current->mempolicy), flags);
Mel Gorman54a6eb52008-04-28 02:12:16 -07001676 for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001677 struct kmem_cache_node *n;
1678
Mel Gorman54a6eb52008-04-28 02:12:16 -07001679 n = get_node(s, zone_to_nid(zone));
Christoph Lameter81819f02007-05-06 14:49:36 -07001680
Mel Gorman54a6eb52008-04-28 02:12:16 -07001681 if (n && cpuset_zone_allowed_hardwall(zone, flags) &&
David Rientjes3b89d7d2009-02-22 17:40:07 -08001682 n->nr_partial > s->min_partial) {
Christoph Lameter497b66f2011-08-09 16:12:26 -05001683 object = get_partial_node(s, n, c);
1684 if (object) {
Miao Xiec0ff7452010-05-24 14:32:08 -07001685 put_mems_allowed();
Christoph Lameter497b66f2011-08-09 16:12:26 -05001686 return object;
Miao Xiec0ff7452010-05-24 14:32:08 -07001687 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001688 }
1689 }
Miao Xiec0ff7452010-05-24 14:32:08 -07001690 put_mems_allowed();
Christoph Lameter81819f02007-05-06 14:49:36 -07001691#endif
1692 return NULL;
1693}
1694
1695/*
1696 * Get a partial page, lock it and return it.
1697 */
Christoph Lameter497b66f2011-08-09 16:12:26 -05001698static void *get_partial(struct kmem_cache *s, gfp_t flags, int node,
Christoph Lameteracd19fd2011-08-09 16:12:25 -05001699 struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07001700{
Christoph Lameter497b66f2011-08-09 16:12:26 -05001701 void *object;
Christoph Lameter2154a332010-07-09 14:07:10 -05001702 int searchnode = (node == NUMA_NO_NODE) ? numa_node_id() : node;
Christoph Lameter81819f02007-05-06 14:49:36 -07001703
Christoph Lameter497b66f2011-08-09 16:12:26 -05001704 object = get_partial_node(s, get_node(s, searchnode), c);
1705 if (object || node != NUMA_NO_NODE)
1706 return object;
Christoph Lameter81819f02007-05-06 14:49:36 -07001707
Christoph Lameteracd19fd2011-08-09 16:12:25 -05001708 return get_any_partial(s, flags, c);
Christoph Lameter81819f02007-05-06 14:49:36 -07001709}
1710
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001711#ifdef CONFIG_PREEMPT
1712/*
1713 * Calculate the next globally unique transaction for disambiguiation
1714 * during cmpxchg. The transactions start with the cpu number and are then
1715 * incremented by CONFIG_NR_CPUS.
1716 */
1717#define TID_STEP roundup_pow_of_two(CONFIG_NR_CPUS)
1718#else
1719/*
1720 * No preemption supported therefore also no need to check for
1721 * different cpus.
1722 */
1723#define TID_STEP 1
1724#endif
1725
1726static inline unsigned long next_tid(unsigned long tid)
1727{
1728 return tid + TID_STEP;
1729}
1730
1731static inline unsigned int tid_to_cpu(unsigned long tid)
1732{
1733 return tid % TID_STEP;
1734}
1735
1736static inline unsigned long tid_to_event(unsigned long tid)
1737{
1738 return tid / TID_STEP;
1739}
1740
1741static inline unsigned int init_tid(int cpu)
1742{
1743 return cpu;
1744}
1745
1746static inline void note_cmpxchg_failure(const char *n,
1747 const struct kmem_cache *s, unsigned long tid)
1748{
1749#ifdef SLUB_DEBUG_CMPXCHG
1750 unsigned long actual_tid = __this_cpu_read(s->cpu_slab->tid);
1751
1752 printk(KERN_INFO "%s %s: cmpxchg redo ", n, s->name);
1753
1754#ifdef CONFIG_PREEMPT
1755 if (tid_to_cpu(tid) != tid_to_cpu(actual_tid))
1756 printk("due to cpu change %d -> %d\n",
1757 tid_to_cpu(tid), tid_to_cpu(actual_tid));
1758 else
1759#endif
1760 if (tid_to_event(tid) != tid_to_event(actual_tid))
1761 printk("due to cpu running other code. Event %ld->%ld\n",
1762 tid_to_event(tid), tid_to_event(actual_tid));
1763 else
1764 printk("for unknown reason: actual=%lx was=%lx target=%lx\n",
1765 actual_tid, tid, next_tid(tid));
1766#endif
Christoph Lameter4fdccdf2011-03-22 13:35:00 -05001767 stat(s, CMPXCHG_DOUBLE_CPU_FAIL);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001768}
1769
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001770void init_kmem_cache_cpus(struct kmem_cache *s)
1771{
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001772 int cpu;
1773
1774 for_each_possible_cpu(cpu)
1775 per_cpu_ptr(s->cpu_slab, cpu)->tid = init_tid(cpu);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001776}
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001777
1778/*
1779 * Remove the cpu slab
1780 */
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001781static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07001782{
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001783 enum slab_modes { M_NONE, M_PARTIAL, M_FULL, M_FREE };
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001784 struct page *page = c->page;
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001785 struct kmem_cache_node *n = get_node(s, page_to_nid(page));
1786 int lock = 0;
1787 enum slab_modes l = M_NONE, m = M_NONE;
1788 void *freelist;
1789 void *nextfree;
1790 int tail = 0;
1791 struct page new;
1792 struct page old;
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08001793
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001794 if (page->freelist) {
Christoph Lameter84e554e62009-12-18 16:26:23 -06001795 stat(s, DEACTIVATE_REMOTE_FREES);
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001796 tail = 1;
Christoph Lameter894b8782007-05-10 03:15:16 -07001797 }
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001798
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06001799 c->tid = next_tid(c->tid);
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001800 c->page = NULL;
1801 freelist = c->freelist;
1802 c->freelist = NULL;
1803
1804 /*
1805 * Stage one: Free all available per cpu objects back
1806 * to the page freelist while it is still frozen. Leave the
1807 * last one.
1808 *
1809 * There is no need to take the list->lock because the page
1810 * is still frozen.
1811 */
1812 while (freelist && (nextfree = get_freepointer(s, freelist))) {
1813 void *prior;
1814 unsigned long counters;
1815
1816 do {
1817 prior = page->freelist;
1818 counters = page->counters;
1819 set_freepointer(s, freelist, prior);
1820 new.counters = counters;
1821 new.inuse--;
1822 VM_BUG_ON(!new.frozen);
1823
Christoph Lameter1d071712011-07-14 12:49:12 -05001824 } while (!__cmpxchg_double_slab(s, page,
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001825 prior, counters,
1826 freelist, new.counters,
1827 "drain percpu freelist"));
1828
1829 freelist = nextfree;
1830 }
1831
1832 /*
1833 * Stage two: Ensure that the page is unfrozen while the
1834 * list presence reflects the actual number of objects
1835 * during unfreeze.
1836 *
1837 * We setup the list membership and then perform a cmpxchg
1838 * with the count. If there is a mismatch then the page
1839 * is not unfrozen but the page is on the wrong list.
1840 *
1841 * Then we restart the process which may have to remove
1842 * the page from the list that we just put it on again
1843 * because the number of objects in the slab may have
1844 * changed.
1845 */
1846redo:
1847
1848 old.freelist = page->freelist;
1849 old.counters = page->counters;
1850 VM_BUG_ON(!old.frozen);
1851
1852 /* Determine target state of the slab */
1853 new.counters = old.counters;
1854 if (freelist) {
1855 new.inuse--;
1856 set_freepointer(s, freelist, old.freelist);
1857 new.freelist = freelist;
1858 } else
1859 new.freelist = old.freelist;
1860
1861 new.frozen = 0;
1862
Christoph Lameter81107182011-08-09 13:01:32 -05001863 if (!new.inuse && n->nr_partial > s->min_partial)
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001864 m = M_FREE;
1865 else if (new.freelist) {
1866 m = M_PARTIAL;
1867 if (!lock) {
1868 lock = 1;
1869 /*
1870 * Taking the spinlock removes the possiblity
1871 * that acquire_slab() will see a slab page that
1872 * is frozen
1873 */
1874 spin_lock(&n->list_lock);
1875 }
1876 } else {
1877 m = M_FULL;
1878 if (kmem_cache_debug(s) && !lock) {
1879 lock = 1;
1880 /*
1881 * This also ensures that the scanning of full
1882 * slabs from diagnostic functions will not see
1883 * any frozen slabs.
1884 */
1885 spin_lock(&n->list_lock);
1886 }
1887 }
1888
1889 if (l != m) {
1890
1891 if (l == M_PARTIAL)
1892
1893 remove_partial(n, page);
1894
1895 else if (l == M_FULL)
1896
1897 remove_full(s, page);
1898
1899 if (m == M_PARTIAL) {
1900
1901 add_partial(n, page, tail);
1902 stat(s, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD);
1903
1904 } else if (m == M_FULL) {
1905
1906 stat(s, DEACTIVATE_FULL);
1907 add_full(s, n, page);
1908
1909 }
1910 }
1911
1912 l = m;
Christoph Lameter1d071712011-07-14 12:49:12 -05001913 if (!__cmpxchg_double_slab(s, page,
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001914 old.freelist, old.counters,
1915 new.freelist, new.counters,
1916 "unfreezing slab"))
1917 goto redo;
1918
Christoph Lameter2cfb7452011-06-01 12:25:52 -05001919 if (lock)
1920 spin_unlock(&n->list_lock);
1921
1922 if (m == M_FREE) {
1923 stat(s, DEACTIVATE_EMPTY);
1924 discard_slab(s, page);
1925 stat(s, FREE_SLAB);
1926 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001927}
1928
Christoph Lameter49e22582011-08-09 16:12:27 -05001929/* Unfreeze all the cpu partial slabs */
1930static void unfreeze_partials(struct kmem_cache *s)
1931{
1932 struct kmem_cache_node *n = NULL;
1933 struct kmem_cache_cpu *c = this_cpu_ptr(s->cpu_slab);
1934 struct page *page;
1935
1936 while ((page = c->partial)) {
1937 enum slab_modes { M_PARTIAL, M_FREE };
1938 enum slab_modes l, m;
1939 struct page new;
1940 struct page old;
1941
1942 c->partial = page->next;
1943 l = M_FREE;
1944
1945 do {
1946
1947 old.freelist = page->freelist;
1948 old.counters = page->counters;
1949 VM_BUG_ON(!old.frozen);
1950
1951 new.counters = old.counters;
1952 new.freelist = old.freelist;
1953
1954 new.frozen = 0;
1955
1956 if (!new.inuse && (!n || n->nr_partial < s->min_partial))
1957 m = M_FREE;
1958 else {
1959 struct kmem_cache_node *n2 = get_node(s,
1960 page_to_nid(page));
1961
1962 m = M_PARTIAL;
1963 if (n != n2) {
1964 if (n)
1965 spin_unlock(&n->list_lock);
1966
1967 n = n2;
1968 spin_lock(&n->list_lock);
1969 }
1970 }
1971
1972 if (l != m) {
1973 if (l == M_PARTIAL)
1974 remove_partial(n, page);
1975 else
1976 add_partial(n, page, 1);
1977
1978 l = m;
1979 }
1980
1981 } while (!cmpxchg_double_slab(s, page,
1982 old.freelist, old.counters,
1983 new.freelist, new.counters,
1984 "unfreezing slab"));
1985
1986 if (m == M_FREE) {
1987 stat(s, DEACTIVATE_EMPTY);
1988 discard_slab(s, page);
1989 stat(s, FREE_SLAB);
1990 }
1991 }
1992
1993 if (n)
1994 spin_unlock(&n->list_lock);
1995}
1996
1997/*
1998 * Put a page that was just frozen (in __slab_free) into a partial page
1999 * slot if available. This is done without interrupts disabled and without
2000 * preemption disabled. The cmpxchg is racy and may put the partial page
2001 * onto a random cpus partial slot.
2002 *
2003 * If we did not find a slot then simply move all the partials to the
2004 * per node partial list.
2005 */
2006int put_cpu_partial(struct kmem_cache *s, struct page *page, int drain)
2007{
2008 struct page *oldpage;
2009 int pages;
2010 int pobjects;
2011
2012 do {
2013 pages = 0;
2014 pobjects = 0;
2015 oldpage = this_cpu_read(s->cpu_slab->partial);
2016
2017 if (oldpage) {
2018 pobjects = oldpage->pobjects;
2019 pages = oldpage->pages;
2020 if (drain && pobjects > s->cpu_partial) {
2021 unsigned long flags;
2022 /*
2023 * partial array is full. Move the existing
2024 * set to the per node partial list.
2025 */
2026 local_irq_save(flags);
2027 unfreeze_partials(s);
2028 local_irq_restore(flags);
2029 pobjects = 0;
2030 pages = 0;
2031 }
2032 }
2033
2034 pages++;
2035 pobjects += page->objects - page->inuse;
2036
2037 page->pages = pages;
2038 page->pobjects = pobjects;
2039 page->next = oldpage;
2040
2041 } while (this_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page) != oldpage);
2042 stat(s, CPU_PARTIAL_FREE);
2043 return pobjects;
2044}
2045
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002046static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07002047{
Christoph Lameter84e554e62009-12-18 16:26:23 -06002048 stat(s, CPUSLAB_FLUSH);
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002049 deactivate_slab(s, c);
Christoph Lameter81819f02007-05-06 14:49:36 -07002050}
2051
2052/*
2053 * Flush cpu slab.
Christoph Lameter6446faa2008-02-15 23:45:26 -08002054 *
Christoph Lameter81819f02007-05-06 14:49:36 -07002055 * Called from IPI handler with interrupts disabled.
2056 */
Christoph Lameter0c710012007-07-17 04:03:24 -07002057static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu)
Christoph Lameter81819f02007-05-06 14:49:36 -07002058{
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002059 struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
Christoph Lameter81819f02007-05-06 14:49:36 -07002060
Christoph Lameter49e22582011-08-09 16:12:27 -05002061 if (likely(c)) {
2062 if (c->page)
2063 flush_slab(s, c);
2064
2065 unfreeze_partials(s);
2066 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002067}
2068
2069static void flush_cpu_slab(void *d)
2070{
2071 struct kmem_cache *s = d;
Christoph Lameter81819f02007-05-06 14:49:36 -07002072
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002073 __flush_cpu_slab(s, smp_processor_id());
Christoph Lameter81819f02007-05-06 14:49:36 -07002074}
2075
2076static void flush_all(struct kmem_cache *s)
2077{
Jens Axboe15c8b6c2008-05-09 09:39:44 +02002078 on_each_cpu(flush_cpu_slab, s, 1);
Christoph Lameter81819f02007-05-06 14:49:36 -07002079}
2080
2081/*
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002082 * Check if the objects in a per cpu structure fit numa
2083 * locality expectations.
2084 */
2085static inline int node_match(struct kmem_cache_cpu *c, int node)
2086{
2087#ifdef CONFIG_NUMA
Christoph Lameter2154a332010-07-09 14:07:10 -05002088 if (node != NUMA_NO_NODE && c->node != node)
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002089 return 0;
2090#endif
2091 return 1;
2092}
2093
Pekka Enberg781b2ba2009-06-10 18:50:32 +03002094static int count_free(struct page *page)
2095{
2096 return page->objects - page->inuse;
2097}
2098
2099static unsigned long count_partial(struct kmem_cache_node *n,
2100 int (*get_count)(struct page *))
2101{
2102 unsigned long flags;
2103 unsigned long x = 0;
2104 struct page *page;
2105
2106 spin_lock_irqsave(&n->list_lock, flags);
2107 list_for_each_entry(page, &n->partial, lru)
2108 x += get_count(page);
2109 spin_unlock_irqrestore(&n->list_lock, flags);
2110 return x;
2111}
2112
Alexander Beregalov26c02cf2009-06-11 14:08:48 +04002113static inline unsigned long node_nr_objs(struct kmem_cache_node *n)
2114{
2115#ifdef CONFIG_SLUB_DEBUG
2116 return atomic_long_read(&n->total_objects);
2117#else
2118 return 0;
2119#endif
2120}
2121
Pekka Enberg781b2ba2009-06-10 18:50:32 +03002122static noinline void
2123slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid)
2124{
2125 int node;
2126
2127 printk(KERN_WARNING
2128 "SLUB: Unable to allocate memory on node %d (gfp=0x%x)\n",
2129 nid, gfpflags);
2130 printk(KERN_WARNING " cache: %s, object size: %d, buffer size: %d, "
2131 "default order: %d, min order: %d\n", s->name, s->objsize,
2132 s->size, oo_order(s->oo), oo_order(s->min));
2133
David Rientjesfa5ec8a2009-07-07 00:14:14 -07002134 if (oo_order(s->min) > get_order(s->objsize))
2135 printk(KERN_WARNING " %s debugging increased min order, use "
2136 "slub_debug=O to disable.\n", s->name);
2137
Pekka Enberg781b2ba2009-06-10 18:50:32 +03002138 for_each_online_node(node) {
2139 struct kmem_cache_node *n = get_node(s, node);
2140 unsigned long nr_slabs;
2141 unsigned long nr_objs;
2142 unsigned long nr_free;
2143
2144 if (!n)
2145 continue;
2146
Alexander Beregalov26c02cf2009-06-11 14:08:48 +04002147 nr_free = count_partial(n, count_free);
2148 nr_slabs = node_nr_slabs(n);
2149 nr_objs = node_nr_objs(n);
Pekka Enberg781b2ba2009-06-10 18:50:32 +03002150
2151 printk(KERN_WARNING
2152 " node %d: slabs: %ld, objs: %ld, free: %ld\n",
2153 node, nr_slabs, nr_objs, nr_free);
2154 }
2155}
2156
Christoph Lameter497b66f2011-08-09 16:12:26 -05002157static inline void *new_slab_objects(struct kmem_cache *s, gfp_t flags,
2158 int node, struct kmem_cache_cpu **pc)
2159{
2160 void *object;
2161 struct kmem_cache_cpu *c;
2162 struct page *page = new_slab(s, flags, node);
2163
2164 if (page) {
2165 c = __this_cpu_ptr(s->cpu_slab);
2166 if (c->page)
2167 flush_slab(s, c);
2168
2169 /*
2170 * No other reference to the page yet so we can
2171 * muck around with it freely without cmpxchg
2172 */
2173 object = page->freelist;
2174 page->freelist = NULL;
2175
2176 stat(s, ALLOC_SLAB);
2177 c->node = page_to_nid(page);
2178 c->page = page;
2179 *pc = c;
2180 } else
2181 object = NULL;
2182
2183 return object;
2184}
2185
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002186/*
Christoph Lameter894b8782007-05-10 03:15:16 -07002187 * Slow path. The lockless freelist is empty or we need to perform
2188 * debugging duties.
Christoph Lameter81819f02007-05-06 14:49:36 -07002189 *
Christoph Lameter894b8782007-05-10 03:15:16 -07002190 * Processing is still very fast if new objects have been freed to the
2191 * regular freelist. In that case we simply take over the regular freelist
2192 * as the lockless freelist and zap the regular freelist.
Christoph Lameter81819f02007-05-06 14:49:36 -07002193 *
Christoph Lameter894b8782007-05-10 03:15:16 -07002194 * If that is not working then we fall back to the partial lists. We take the
2195 * first element of the freelist as the object to allocate now and move the
2196 * rest of the freelist to the lockless freelist.
2197 *
2198 * And if we were unable to get a new slab from the partial slab lists then
Christoph Lameter6446faa2008-02-15 23:45:26 -08002199 * we need to allocate a new slab. This is the slowest path since it involves
2200 * a call to the page allocator and the setup of a new slab.
Christoph Lameter81819f02007-05-06 14:49:36 -07002201 */
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03002202static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
2203 unsigned long addr, struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07002204{
Christoph Lameter81819f02007-05-06 14:49:36 -07002205 void **object;
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002206 unsigned long flags;
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002207 struct page new;
2208 unsigned long counters;
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002209
2210 local_irq_save(flags);
2211#ifdef CONFIG_PREEMPT
2212 /*
2213 * We may have been preempted and rescheduled on a different
2214 * cpu before disabling interrupts. Need to reload cpu area
2215 * pointer.
2216 */
2217 c = this_cpu_ptr(s->cpu_slab);
2218#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07002219
Christoph Lameter497b66f2011-08-09 16:12:26 -05002220 if (!c->page)
Christoph Lameter81819f02007-05-06 14:49:36 -07002221 goto new_slab;
Christoph Lameter49e22582011-08-09 16:12:27 -05002222redo:
Christoph Lameterfc59c052011-06-01 12:25:56 -05002223 if (unlikely(!node_match(c, node))) {
Christoph Lametere36a2652011-06-01 12:25:57 -05002224 stat(s, ALLOC_NODE_MISMATCH);
Christoph Lameterfc59c052011-06-01 12:25:56 -05002225 deactivate_slab(s, c);
2226 goto new_slab;
2227 }
Christoph Lameter6446faa2008-02-15 23:45:26 -08002228
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002229 stat(s, ALLOC_SLOWPATH);
2230
2231 do {
Christoph Lameter497b66f2011-08-09 16:12:26 -05002232 object = c->page->freelist;
2233 counters = c->page->counters;
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002234 new.counters = counters;
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002235 VM_BUG_ON(!new.frozen);
2236
Christoph Lameter03e404a2011-06-01 12:25:58 -05002237 /*
2238 * If there is no object left then we use this loop to
2239 * deactivate the slab which is simple since no objects
2240 * are left in the slab and therefore we do not need to
2241 * put the page back onto the partial list.
2242 *
2243 * If there are objects left then we retrieve them
2244 * and use them to refill the per cpu queue.
Christoph Lameter497b66f2011-08-09 16:12:26 -05002245 */
Christoph Lameter03e404a2011-06-01 12:25:58 -05002246
Christoph Lameter497b66f2011-08-09 16:12:26 -05002247 new.inuse = c->page->objects;
Christoph Lameter03e404a2011-06-01 12:25:58 -05002248 new.frozen = object != NULL;
2249
Christoph Lameter497b66f2011-08-09 16:12:26 -05002250 } while (!__cmpxchg_double_slab(s, c->page,
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002251 object, counters,
2252 NULL, new.counters,
2253 "__slab_alloc"));
Christoph Lameter6446faa2008-02-15 23:45:26 -08002254
Christoph Lameter49e22582011-08-09 16:12:27 -05002255 if (!object) {
Christoph Lameter03e404a2011-06-01 12:25:58 -05002256 c->page = NULL;
2257 stat(s, DEACTIVATE_BYPASS);
Christoph Lameterfc59c052011-06-01 12:25:56 -05002258 goto new_slab;
Christoph Lameter03e404a2011-06-01 12:25:58 -05002259 }
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002260
Christoph Lameter81819f02007-05-06 14:49:36 -07002261 stat(s, ALLOC_REFILL);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08002262
Christoph Lameter894b8782007-05-10 03:15:16 -07002263load_freelist:
Christoph Lameterff120592009-12-18 16:26:22 -06002264 c->freelist = get_freepointer(s, object);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002265 c->tid = next_tid(c->tid);
2266 local_irq_restore(flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07002267 return object;
2268
Christoph Lameter81819f02007-05-06 14:49:36 -07002269new_slab:
Christoph Lameter49e22582011-08-09 16:12:27 -05002270
2271 if (c->partial) {
2272 c->page = c->partial;
2273 c->partial = c->page->next;
2274 c->node = page_to_nid(c->page);
2275 stat(s, CPU_PARTIAL_ALLOC);
2276 c->freelist = NULL;
2277 goto redo;
2278 }
2279
2280 /* Then do expensive stuff like retrieving pages from the partial lists */
Christoph Lameter497b66f2011-08-09 16:12:26 -05002281 object = get_partial(s, gfpflags, node, c);
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002282
Christoph Lameter497b66f2011-08-09 16:12:26 -05002283 if (unlikely(!object)) {
2284
2285 object = new_slab_objects(s, gfpflags, node, &c);
2286
2287 if (unlikely(!object)) {
2288 if (!(gfpflags & __GFP_NOWARN) && printk_ratelimit())
2289 slab_out_of_memory(s, gfpflags, node);
2290
2291 local_irq_restore(flags);
2292 return NULL;
2293 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002294 }
2295
Christoph Lameter497b66f2011-08-09 16:12:26 -05002296 if (likely(!kmem_cache_debug(s)))
Christoph Lameter4b6f0752007-05-16 22:10:53 -07002297 goto load_freelist;
Christoph Lameter894b8782007-05-10 03:15:16 -07002298
Christoph Lameter497b66f2011-08-09 16:12:26 -05002299 /* Only entered in the debug case */
2300 if (!alloc_debug_processing(s, c->page, object, addr))
2301 goto new_slab; /* Slab failed checks. Next slab needed */
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002302
2303 c->freelist = get_freepointer(s, object);
Christoph Lameter442b06b2011-05-17 16:29:31 -05002304 deactivate_slab(s, c);
Pekka Enberg15b7c512010-10-02 11:32:32 +03002305 c->node = NUMA_NO_NODE;
Christoph Lametera71ae472011-05-25 09:47:43 -05002306 local_irq_restore(flags);
2307 return object;
Christoph Lameter894b8782007-05-10 03:15:16 -07002308}
2309
2310/*
2311 * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc)
2312 * have the fastpath folded into their functions. So no function call
2313 * overhead for requests that can be satisfied on the fastpath.
2314 *
2315 * The fastpath works by first checking if the lockless freelist can be used.
2316 * If not then __slab_alloc is called for slow processing.
2317 *
2318 * Otherwise we can simply pick the next object from the lockless free list.
2319 */
Pekka Enberg06428782008-01-07 23:20:27 -08002320static __always_inline void *slab_alloc(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03002321 gfp_t gfpflags, int node, unsigned long addr)
Christoph Lameter894b8782007-05-10 03:15:16 -07002322{
Christoph Lameter894b8782007-05-10 03:15:16 -07002323 void **object;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002324 struct kmem_cache_cpu *c;
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002325 unsigned long tid;
Christoph Lameter1f842602008-01-07 23:20:30 -08002326
Christoph Lameterc016b0b2010-08-20 12:37:16 -05002327 if (slab_pre_alloc_hook(s, gfpflags))
Akinobu Mita773ff602008-12-23 19:37:01 +09002328 return NULL;
2329
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002330redo:
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002331
2332 /*
2333 * Must read kmem_cache cpu data via this cpu ptr. Preemption is
2334 * enabled. We may switch back and forth between cpus while
2335 * reading from one cpu area. That does not matter as long
2336 * as we end up on the original cpu again when doing the cmpxchg.
2337 */
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002338 c = __this_cpu_ptr(s->cpu_slab);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002339
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002340 /*
2341 * The transaction ids are globally unique per cpu and per operation on
2342 * a per cpu queue. Thus they can be guarantee that the cmpxchg_double
2343 * occurs on the right processor and that there was no operation on the
2344 * linked list in between.
2345 */
2346 tid = c->tid;
2347 barrier();
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002348
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002349 object = c->freelist;
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002350 if (unlikely(!object || !node_match(c, node)))
Christoph Lameter894b8782007-05-10 03:15:16 -07002351
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002352 object = __slab_alloc(s, gfpflags, node, addr, c);
Christoph Lameter894b8782007-05-10 03:15:16 -07002353
2354 else {
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002355 /*
Lucas De Marchi25985ed2011-03-30 22:57:33 -03002356 * The cmpxchg will only match if there was no additional
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002357 * operation and if we are on the right processor.
2358 *
2359 * The cmpxchg does the following atomically (without lock semantics!)
2360 * 1. Relocate first pointer to the current per cpu area.
2361 * 2. Verify that tid and freelist have not been changed
2362 * 3. If they were not changed replace tid and freelist
2363 *
2364 * Since this is without lock semantics the protection is only against
2365 * code executing on this cpu *not* from access by other cpus.
2366 */
Thomas Gleixner30106b82011-05-04 15:38:19 +02002367 if (unlikely(!irqsafe_cpu_cmpxchg_double(
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002368 s->cpu_slab->freelist, s->cpu_slab->tid,
2369 object, tid,
Christoph Lameter1393d9a2011-05-16 15:26:08 -05002370 get_freepointer_safe(s, object), next_tid(tid)))) {
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002371
2372 note_cmpxchg_failure("slab_alloc", s, tid);
2373 goto redo;
2374 }
Christoph Lameter84e554e62009-12-18 16:26:23 -06002375 stat(s, ALLOC_FASTPATH);
Christoph Lameter894b8782007-05-10 03:15:16 -07002376 }
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002377
Pekka Enberg74e21342009-11-25 20:14:48 +02002378 if (unlikely(gfpflags & __GFP_ZERO) && object)
Christoph Lameterff120592009-12-18 16:26:22 -06002379 memset(object, 0, s->objsize);
Christoph Lameterd07dbea2007-07-17 04:03:23 -07002380
Christoph Lameterc016b0b2010-08-20 12:37:16 -05002381 slab_post_alloc_hook(s, gfpflags, object);
Vegard Nossum5a896d92008-04-04 00:54:48 +02002382
Christoph Lameter894b8782007-05-10 03:15:16 -07002383 return object;
Christoph Lameter81819f02007-05-06 14:49:36 -07002384}
2385
2386void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags)
2387{
Christoph Lameter2154a332010-07-09 14:07:10 -05002388 void *ret = slab_alloc(s, gfpflags, NUMA_NO_NODE, _RET_IP_);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002389
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02002390 trace_kmem_cache_alloc(_RET_IP_, ret, s->objsize, s->size, gfpflags);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002391
2392 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002393}
2394EXPORT_SYMBOL(kmem_cache_alloc);
2395
Li Zefan0f24f122009-12-11 15:45:30 +08002396#ifdef CONFIG_TRACING
Richard Kennedy4a923792010-10-21 10:29:19 +01002397void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size)
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002398{
Richard Kennedy4a923792010-10-21 10:29:19 +01002399 void *ret = slab_alloc(s, gfpflags, NUMA_NO_NODE, _RET_IP_);
2400 trace_kmalloc(_RET_IP_, ret, size, s->size, gfpflags);
2401 return ret;
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002402}
Richard Kennedy4a923792010-10-21 10:29:19 +01002403EXPORT_SYMBOL(kmem_cache_alloc_trace);
2404
2405void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
2406{
2407 void *ret = kmalloc_order(size, flags, order);
2408 trace_kmalloc(_RET_IP_, ret, size, PAGE_SIZE << order, flags);
2409 return ret;
2410}
2411EXPORT_SYMBOL(kmalloc_order_trace);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002412#endif
2413
Christoph Lameter81819f02007-05-06 14:49:36 -07002414#ifdef CONFIG_NUMA
2415void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node)
2416{
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002417 void *ret = slab_alloc(s, gfpflags, node, _RET_IP_);
2418
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02002419 trace_kmem_cache_alloc_node(_RET_IP_, ret,
2420 s->objsize, s->size, gfpflags, node);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002421
2422 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002423}
2424EXPORT_SYMBOL(kmem_cache_alloc_node);
Christoph Lameter81819f02007-05-06 14:49:36 -07002425
Li Zefan0f24f122009-12-11 15:45:30 +08002426#ifdef CONFIG_TRACING
Richard Kennedy4a923792010-10-21 10:29:19 +01002427void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002428 gfp_t gfpflags,
Richard Kennedy4a923792010-10-21 10:29:19 +01002429 int node, size_t size)
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002430{
Richard Kennedy4a923792010-10-21 10:29:19 +01002431 void *ret = slab_alloc(s, gfpflags, node, _RET_IP_);
2432
2433 trace_kmalloc_node(_RET_IP_, ret,
2434 size, s->size, gfpflags, node);
2435 return ret;
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002436}
Richard Kennedy4a923792010-10-21 10:29:19 +01002437EXPORT_SYMBOL(kmem_cache_alloc_node_trace);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002438#endif
Namhyung Kim5d1f57e2010-09-29 21:02:15 +09002439#endif
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002440
Christoph Lameter81819f02007-05-06 14:49:36 -07002441/*
Christoph Lameter894b8782007-05-10 03:15:16 -07002442 * Slow patch handling. This may still be called frequently since objects
2443 * have a longer lifetime than the cpu slabs in most processing loads.
Christoph Lameter81819f02007-05-06 14:49:36 -07002444 *
Christoph Lameter894b8782007-05-10 03:15:16 -07002445 * So we still attempt to reduce cache line usage. Just take the slab
2446 * lock and free the item. If there is no additional partial page
2447 * handling required then we can return immediately.
Christoph Lameter81819f02007-05-06 14:49:36 -07002448 */
Christoph Lameter894b8782007-05-10 03:15:16 -07002449static void __slab_free(struct kmem_cache *s, struct page *page,
Christoph Lameterff120592009-12-18 16:26:22 -06002450 void *x, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -07002451{
2452 void *prior;
2453 void **object = (void *)x;
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002454 int was_frozen;
2455 int inuse;
2456 struct page new;
2457 unsigned long counters;
2458 struct kmem_cache_node *n = NULL;
Christoph Lameter61728d12011-06-01 12:25:51 -05002459 unsigned long uninitialized_var(flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07002460
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002461 stat(s, FREE_SLOWPATH);
Christoph Lameter81819f02007-05-06 14:49:36 -07002462
Christoph Lameter8dc16c62011-04-15 14:48:16 -05002463 if (kmem_cache_debug(s) && !free_debug_processing(s, page, x, addr))
Christoph Lameter80f08c12011-06-01 12:25:55 -05002464 return;
Christoph Lameter6446faa2008-02-15 23:45:26 -08002465
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002466 do {
2467 prior = page->freelist;
2468 counters = page->counters;
2469 set_freepointer(s, object, prior);
2470 new.counters = counters;
2471 was_frozen = new.frozen;
2472 new.inuse--;
2473 if ((!new.inuse || !prior) && !was_frozen && !n) {
Christoph Lameter49e22582011-08-09 16:12:27 -05002474
2475 if (!kmem_cache_debug(s) && !prior)
2476
2477 /*
2478 * Slab was on no list before and will be partially empty
2479 * We can defer the list move and instead freeze it.
2480 */
2481 new.frozen = 1;
2482
2483 else { /* Needs to be taken off a list */
2484
2485 n = get_node(s, page_to_nid(page));
2486 /*
2487 * Speculatively acquire the list_lock.
2488 * If the cmpxchg does not succeed then we may
2489 * drop the list_lock without any processing.
2490 *
2491 * Otherwise the list_lock will synchronize with
2492 * other processors updating the list of slabs.
2493 */
2494 spin_lock_irqsave(&n->list_lock, flags);
2495
2496 }
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002497 }
2498 inuse = new.inuse;
Christoph Lameter81819f02007-05-06 14:49:36 -07002499
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002500 } while (!cmpxchg_double_slab(s, page,
2501 prior, counters,
2502 object, new.counters,
2503 "__slab_free"));
Christoph Lameter81819f02007-05-06 14:49:36 -07002504
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002505 if (likely(!n)) {
Christoph Lameter49e22582011-08-09 16:12:27 -05002506
2507 /*
2508 * If we just froze the page then put it onto the
2509 * per cpu partial list.
2510 */
2511 if (new.frozen && !was_frozen)
2512 put_cpu_partial(s, page, 1);
2513
2514 /*
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002515 * The list lock was not taken therefore no list
2516 * activity can be necessary.
2517 */
2518 if (was_frozen)
2519 stat(s, FREE_FROZEN);
Christoph Lameter80f08c12011-06-01 12:25:55 -05002520 return;
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002521 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002522
2523 /*
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002524 * was_frozen may have been set after we acquired the list_lock in
2525 * an earlier loop. So we need to check it here again.
Christoph Lameter81819f02007-05-06 14:49:36 -07002526 */
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002527 if (was_frozen)
2528 stat(s, FREE_FROZEN);
2529 else {
2530 if (unlikely(!inuse && n->nr_partial > s->min_partial))
2531 goto slab_empty;
Christoph Lameter81819f02007-05-06 14:49:36 -07002532
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002533 /*
2534 * Objects left in the slab. If it was not on the partial list before
2535 * then add it.
2536 */
2537 if (unlikely(!prior)) {
2538 remove_full(s, page);
2539 add_partial(n, page, 0);
2540 stat(s, FREE_ADD_PARTIAL);
2541 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002542 }
Christoph Lameter80f08c12011-06-01 12:25:55 -05002543 spin_unlock_irqrestore(&n->list_lock, flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07002544 return;
2545
2546slab_empty:
Christoph Lametera973e9d2008-03-01 13:40:44 -08002547 if (prior) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002548 /*
Christoph Lameter6fbabb22011-08-08 11:16:56 -05002549 * Slab on the partial list.
Christoph Lameter81819f02007-05-06 14:49:36 -07002550 */
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05002551 remove_partial(n, page);
Christoph Lameter84e554e62009-12-18 16:26:23 -06002552 stat(s, FREE_REMOVE_PARTIAL);
Christoph Lameter6fbabb22011-08-08 11:16:56 -05002553 } else
2554 /* Slab must be on the full list */
2555 remove_full(s, page);
Christoph Lameter2cfb7452011-06-01 12:25:52 -05002556
Christoph Lameter80f08c12011-06-01 12:25:55 -05002557 spin_unlock_irqrestore(&n->list_lock, flags);
Christoph Lameter84e554e62009-12-18 16:26:23 -06002558 stat(s, FREE_SLAB);
Christoph Lameter81819f02007-05-06 14:49:36 -07002559 discard_slab(s, page);
Christoph Lameter81819f02007-05-06 14:49:36 -07002560}
2561
Christoph Lameter894b8782007-05-10 03:15:16 -07002562/*
2563 * Fastpath with forced inlining to produce a kfree and kmem_cache_free that
2564 * can perform fastpath freeing without additional function calls.
2565 *
2566 * The fastpath is only possible if we are freeing to the current cpu slab
2567 * of this processor. This typically the case if we have just allocated
2568 * the item before.
2569 *
2570 * If fastpath is not possible then fall back to __slab_free where we deal
2571 * with all sorts of special processing.
2572 */
Pekka Enberg06428782008-01-07 23:20:27 -08002573static __always_inline void slab_free(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03002574 struct page *page, void *x, unsigned long addr)
Christoph Lameter894b8782007-05-10 03:15:16 -07002575{
2576 void **object = (void *)x;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002577 struct kmem_cache_cpu *c;
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002578 unsigned long tid;
Christoph Lameter1f842602008-01-07 23:20:30 -08002579
Christoph Lameterc016b0b2010-08-20 12:37:16 -05002580 slab_free_hook(s, x);
2581
Christoph Lametera24c5a02011-03-15 12:45:21 -05002582redo:
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002583 /*
2584 * Determine the currently cpus per cpu slab.
2585 * The cpu may change afterward. However that does not matter since
2586 * data is retrieved via this pointer. If we are on the same cpu
2587 * during the cmpxchg then the free will succedd.
2588 */
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002589 c = __this_cpu_ptr(s->cpu_slab);
Christoph Lameterc016b0b2010-08-20 12:37:16 -05002590
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002591 tid = c->tid;
2592 barrier();
Christoph Lameterc016b0b2010-08-20 12:37:16 -05002593
Christoph Lameter442b06b2011-05-17 16:29:31 -05002594 if (likely(page == c->page)) {
Christoph Lameterff120592009-12-18 16:26:22 -06002595 set_freepointer(s, object, c->freelist);
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002596
Thomas Gleixner30106b82011-05-04 15:38:19 +02002597 if (unlikely(!irqsafe_cpu_cmpxchg_double(
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002598 s->cpu_slab->freelist, s->cpu_slab->tid,
2599 c->freelist, tid,
2600 object, next_tid(tid)))) {
2601
2602 note_cmpxchg_failure("slab_free", s, tid);
2603 goto redo;
2604 }
Christoph Lameter84e554e62009-12-18 16:26:23 -06002605 stat(s, FREE_FASTPATH);
Christoph Lameter894b8782007-05-10 03:15:16 -07002606 } else
Christoph Lameterff120592009-12-18 16:26:22 -06002607 __slab_free(s, page, x, addr);
Christoph Lameter894b8782007-05-10 03:15:16 -07002608
Christoph Lameter894b8782007-05-10 03:15:16 -07002609}
2610
Christoph Lameter81819f02007-05-06 14:49:36 -07002611void kmem_cache_free(struct kmem_cache *s, void *x)
2612{
Christoph Lameter77c5e2d2007-05-06 14:49:42 -07002613 struct page *page;
Christoph Lameter81819f02007-05-06 14:49:36 -07002614
Christoph Lameterb49af682007-05-06 14:49:41 -07002615 page = virt_to_head_page(x);
Christoph Lameter81819f02007-05-06 14:49:36 -07002616
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03002617 slab_free(s, page, x, _RET_IP_);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002618
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02002619 trace_kmem_cache_free(_RET_IP_, x);
Christoph Lameter81819f02007-05-06 14:49:36 -07002620}
2621EXPORT_SYMBOL(kmem_cache_free);
2622
Christoph Lameter81819f02007-05-06 14:49:36 -07002623/*
Christoph Lameter672bba32007-05-09 02:32:39 -07002624 * Object placement in a slab is made very easy because we always start at
2625 * offset 0. If we tune the size of the object to the alignment then we can
2626 * get the required alignment by putting one properly sized object after
2627 * another.
Christoph Lameter81819f02007-05-06 14:49:36 -07002628 *
2629 * Notice that the allocation order determines the sizes of the per cpu
2630 * caches. Each processor has always one slab available for allocations.
2631 * Increasing the allocation order reduces the number of times that slabs
Christoph Lameter672bba32007-05-09 02:32:39 -07002632 * must be moved on and off the partial lists and is therefore a factor in
Christoph Lameter81819f02007-05-06 14:49:36 -07002633 * locking overhead.
Christoph Lameter81819f02007-05-06 14:49:36 -07002634 */
2635
2636/*
2637 * Mininum / Maximum order of slab pages. This influences locking overhead
2638 * and slab fragmentation. A higher order reduces the number of partial slabs
2639 * and increases the number of allocations possible without having to
2640 * take the list_lock.
2641 */
2642static int slub_min_order;
Christoph Lameter114e9e82008-04-14 19:11:41 +03002643static int slub_max_order = PAGE_ALLOC_COSTLY_ORDER;
Christoph Lameter9b2cd502008-04-14 19:11:41 +03002644static int slub_min_objects;
Christoph Lameter81819f02007-05-06 14:49:36 -07002645
2646/*
2647 * Merge control. If this is set then no merging of slab caches will occur.
Christoph Lameter672bba32007-05-09 02:32:39 -07002648 * (Could be removed. This was introduced to pacify the merge skeptics.)
Christoph Lameter81819f02007-05-06 14:49:36 -07002649 */
2650static int slub_nomerge;
2651
2652/*
Christoph Lameter81819f02007-05-06 14:49:36 -07002653 * Calculate the order of allocation given an slab object size.
2654 *
Christoph Lameter672bba32007-05-09 02:32:39 -07002655 * The order of allocation has significant impact on performance and other
2656 * system components. Generally order 0 allocations should be preferred since
2657 * order 0 does not cause fragmentation in the page allocator. Larger objects
2658 * be problematic to put into order 0 slabs because there may be too much
Christoph Lameterc124f5b2008-04-14 19:13:29 +03002659 * unused space left. We go to a higher order if more than 1/16th of the slab
Christoph Lameter672bba32007-05-09 02:32:39 -07002660 * would be wasted.
Christoph Lameter81819f02007-05-06 14:49:36 -07002661 *
Christoph Lameter672bba32007-05-09 02:32:39 -07002662 * In order to reach satisfactory performance we must ensure that a minimum
2663 * number of objects is in one slab. Otherwise we may generate too much
2664 * activity on the partial lists which requires taking the list_lock. This is
2665 * less a concern for large slabs though which are rarely used.
Christoph Lameter81819f02007-05-06 14:49:36 -07002666 *
Christoph Lameter672bba32007-05-09 02:32:39 -07002667 * slub_max_order specifies the order where we begin to stop considering the
2668 * number of objects in a slab as critical. If we reach slub_max_order then
2669 * we try to keep the page order as low as possible. So we accept more waste
2670 * of space in favor of a small page order.
2671 *
2672 * Higher order allocations also allow the placement of more objects in a
2673 * slab and thereby reduce object handling overhead. If the user has
2674 * requested a higher mininum order then we start with that one instead of
2675 * the smallest order which will fit the object.
Christoph Lameter81819f02007-05-06 14:49:36 -07002676 */
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002677static inline int slab_order(int size, int min_objects,
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002678 int max_order, int fract_leftover, int reserved)
Christoph Lameter81819f02007-05-06 14:49:36 -07002679{
2680 int order;
2681 int rem;
Christoph Lameter6300ea72007-07-17 04:03:20 -07002682 int min_order = slub_min_order;
Christoph Lameter81819f02007-05-06 14:49:36 -07002683
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002684 if (order_objects(min_order, size, reserved) > MAX_OBJS_PER_PAGE)
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +04002685 return get_order(size * MAX_OBJS_PER_PAGE) - 1;
Christoph Lameter39b26462008-04-14 19:11:30 +03002686
Christoph Lameter6300ea72007-07-17 04:03:20 -07002687 for (order = max(min_order,
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002688 fls(min_objects * size - 1) - PAGE_SHIFT);
2689 order <= max_order; order++) {
2690
Christoph Lameter81819f02007-05-06 14:49:36 -07002691 unsigned long slab_size = PAGE_SIZE << order;
2692
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002693 if (slab_size < min_objects * size + reserved)
Christoph Lameter81819f02007-05-06 14:49:36 -07002694 continue;
2695
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002696 rem = (slab_size - reserved) % size;
Christoph Lameter81819f02007-05-06 14:49:36 -07002697
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002698 if (rem <= slab_size / fract_leftover)
Christoph Lameter81819f02007-05-06 14:49:36 -07002699 break;
2700
2701 }
Christoph Lameter672bba32007-05-09 02:32:39 -07002702
Christoph Lameter81819f02007-05-06 14:49:36 -07002703 return order;
2704}
2705
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002706static inline int calculate_order(int size, int reserved)
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002707{
2708 int order;
2709 int min_objects;
2710 int fraction;
Zhang Yanmine8120ff2009-02-12 18:00:17 +02002711 int max_objects;
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002712
2713 /*
2714 * Attempt to find best configuration for a slab. This
2715 * works by first attempting to generate a layout with
2716 * the best configuration and backing off gradually.
2717 *
2718 * First we reduce the acceptable waste in a slab. Then
2719 * we reduce the minimum objects required in a slab.
2720 */
2721 min_objects = slub_min_objects;
Christoph Lameter9b2cd502008-04-14 19:11:41 +03002722 if (!min_objects)
2723 min_objects = 4 * (fls(nr_cpu_ids) + 1);
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002724 max_objects = order_objects(slub_max_order, size, reserved);
Zhang Yanmine8120ff2009-02-12 18:00:17 +02002725 min_objects = min(min_objects, max_objects);
2726
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002727 while (min_objects > 1) {
Christoph Lameterc124f5b2008-04-14 19:13:29 +03002728 fraction = 16;
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002729 while (fraction >= 4) {
2730 order = slab_order(size, min_objects,
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002731 slub_max_order, fraction, reserved);
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002732 if (order <= slub_max_order)
2733 return order;
2734 fraction /= 2;
2735 }
Amerigo Wang5086c389c2009-08-19 21:44:13 +03002736 min_objects--;
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002737 }
2738
2739 /*
2740 * We were unable to place multiple objects in a slab. Now
2741 * lets see if we can place a single object there.
2742 */
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002743 order = slab_order(size, 1, slub_max_order, 1, reserved);
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002744 if (order <= slub_max_order)
2745 return order;
2746
2747 /*
2748 * Doh this slab cannot be placed using slub_max_order.
2749 */
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08002750 order = slab_order(size, 1, MAX_ORDER, 1, reserved);
David Rientjes818cf592009-04-23 09:58:22 +03002751 if (order < MAX_ORDER)
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002752 return order;
2753 return -ENOSYS;
2754}
2755
Christoph Lameter81819f02007-05-06 14:49:36 -07002756/*
Christoph Lameter672bba32007-05-09 02:32:39 -07002757 * Figure out what the alignment of the objects will be.
Christoph Lameter81819f02007-05-06 14:49:36 -07002758 */
2759static unsigned long calculate_alignment(unsigned long flags,
2760 unsigned long align, unsigned long size)
2761{
2762 /*
Christoph Lameter6446faa2008-02-15 23:45:26 -08002763 * If the user wants hardware cache aligned objects then follow that
2764 * suggestion if the object is sufficiently large.
Christoph Lameter81819f02007-05-06 14:49:36 -07002765 *
Christoph Lameter6446faa2008-02-15 23:45:26 -08002766 * The hardware cache alignment cannot override the specified
2767 * alignment though. If that is greater then use it.
Christoph Lameter81819f02007-05-06 14:49:36 -07002768 */
Nick Pigginb6210382008-03-05 14:05:56 -08002769 if (flags & SLAB_HWCACHE_ALIGN) {
2770 unsigned long ralign = cache_line_size();
2771 while (size <= ralign / 2)
2772 ralign /= 2;
2773 align = max(align, ralign);
2774 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002775
2776 if (align < ARCH_SLAB_MINALIGN)
Nick Pigginb6210382008-03-05 14:05:56 -08002777 align = ARCH_SLAB_MINALIGN;
Christoph Lameter81819f02007-05-06 14:49:36 -07002778
2779 return ALIGN(align, sizeof(void *));
2780}
2781
Pekka Enberg5595cff2008-08-05 09:28:47 +03002782static void
2783init_kmem_cache_node(struct kmem_cache_node *n, struct kmem_cache *s)
Christoph Lameter81819f02007-05-06 14:49:36 -07002784{
2785 n->nr_partial = 0;
Christoph Lameter81819f02007-05-06 14:49:36 -07002786 spin_lock_init(&n->list_lock);
2787 INIT_LIST_HEAD(&n->partial);
Christoph Lameter8ab13722007-07-17 04:03:32 -07002788#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter0f389ec2008-04-14 18:53:02 +03002789 atomic_long_set(&n->nr_slabs, 0);
Salman Qazi02b71b72008-09-11 12:25:41 -07002790 atomic_long_set(&n->total_objects, 0);
Christoph Lameter643b1132007-05-06 14:49:42 -07002791 INIT_LIST_HEAD(&n->full);
Christoph Lameter8ab13722007-07-17 04:03:32 -07002792#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07002793}
2794
Christoph Lameter55136592010-08-20 12:37:13 -05002795static inline int alloc_kmem_cache_cpus(struct kmem_cache *s)
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002796{
Christoph Lameter6c182dc2010-08-20 12:37:14 -05002797 BUILD_BUG_ON(PERCPU_DYNAMIC_EARLY_SIZE <
2798 SLUB_PAGE_SHIFT * sizeof(struct kmem_cache_cpu));
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002799
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002800 /*
Chris Metcalfd4d84fe2011-06-02 10:19:41 -04002801 * Must align to double word boundary for the double cmpxchg
2802 * instructions to work; see __pcpu_double_call_return_bool().
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002803 */
Chris Metcalfd4d84fe2011-06-02 10:19:41 -04002804 s->cpu_slab = __alloc_percpu(sizeof(struct kmem_cache_cpu),
2805 2 * sizeof(void *));
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002806
Christoph Lameter8a5ec0b2011-02-25 11:38:54 -06002807 if (!s->cpu_slab)
2808 return 0;
2809
2810 init_kmem_cache_cpus(s);
2811
2812 return 1;
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002813}
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002814
Christoph Lameter51df1142010-08-20 12:37:15 -05002815static struct kmem_cache *kmem_cache_node;
2816
Christoph Lameter81819f02007-05-06 14:49:36 -07002817/*
2818 * No kmalloc_node yet so do it by hand. We know that this is the first
2819 * slab on the node for this slabcache. There are no concurrent accesses
2820 * possible.
2821 *
2822 * Note that this function only works on the kmalloc_node_cache
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002823 * when allocating for the kmalloc_node_cache. This is used for bootstrapping
2824 * memory on a fresh node that has no slab structures yet.
Christoph Lameter81819f02007-05-06 14:49:36 -07002825 */
Christoph Lameter55136592010-08-20 12:37:13 -05002826static void early_kmem_cache_node_alloc(int node)
Christoph Lameter81819f02007-05-06 14:49:36 -07002827{
2828 struct page *page;
2829 struct kmem_cache_node *n;
2830
Christoph Lameter51df1142010-08-20 12:37:15 -05002831 BUG_ON(kmem_cache_node->size < sizeof(struct kmem_cache_node));
Christoph Lameter81819f02007-05-06 14:49:36 -07002832
Christoph Lameter51df1142010-08-20 12:37:15 -05002833 page = new_slab(kmem_cache_node, GFP_NOWAIT, node);
Christoph Lameter81819f02007-05-06 14:49:36 -07002834
2835 BUG_ON(!page);
Christoph Lametera2f92ee2007-08-22 14:01:57 -07002836 if (page_to_nid(page) != node) {
2837 printk(KERN_ERR "SLUB: Unable to allocate memory from "
2838 "node %d\n", node);
2839 printk(KERN_ERR "SLUB: Allocating a useless per node structure "
2840 "in order to be able to continue\n");
2841 }
2842
Christoph Lameter81819f02007-05-06 14:49:36 -07002843 n = page->freelist;
2844 BUG_ON(!n);
Christoph Lameter51df1142010-08-20 12:37:15 -05002845 page->freelist = get_freepointer(kmem_cache_node, n);
Christoph Lametere6e82ea2011-08-09 16:12:24 -05002846 page->inuse = 1;
Christoph Lameter8cb0a502011-06-01 12:25:46 -05002847 page->frozen = 0;
Christoph Lameter51df1142010-08-20 12:37:15 -05002848 kmem_cache_node->node[node] = n;
Christoph Lameter8ab13722007-07-17 04:03:32 -07002849#ifdef CONFIG_SLUB_DEBUG
Christoph Lameterf7cb1932010-09-29 07:15:01 -05002850 init_object(kmem_cache_node, n, SLUB_RED_ACTIVE);
Christoph Lameter51df1142010-08-20 12:37:15 -05002851 init_tracking(kmem_cache_node, n);
Christoph Lameter8ab13722007-07-17 04:03:32 -07002852#endif
Christoph Lameter51df1142010-08-20 12:37:15 -05002853 init_kmem_cache_node(n, kmem_cache_node);
2854 inc_slabs_node(kmem_cache_node, node, page->objects);
Christoph Lameter6446faa2008-02-15 23:45:26 -08002855
Christoph Lameter7c2e1322008-01-07 23:20:27 -08002856 add_partial(n, page, 0);
Christoph Lameter81819f02007-05-06 14:49:36 -07002857}
2858
2859static void free_kmem_cache_nodes(struct kmem_cache *s)
2860{
2861 int node;
2862
Christoph Lameterf64dc582007-10-16 01:25:33 -07002863 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002864 struct kmem_cache_node *n = s->node[node];
Christoph Lameter51df1142010-08-20 12:37:15 -05002865
Alexander Duyck73367bd2010-05-21 14:41:35 -07002866 if (n)
Christoph Lameter51df1142010-08-20 12:37:15 -05002867 kmem_cache_free(kmem_cache_node, n);
2868
Christoph Lameter81819f02007-05-06 14:49:36 -07002869 s->node[node] = NULL;
2870 }
2871}
2872
Christoph Lameter55136592010-08-20 12:37:13 -05002873static int init_kmem_cache_nodes(struct kmem_cache *s)
Christoph Lameter81819f02007-05-06 14:49:36 -07002874{
2875 int node;
Christoph Lameter81819f02007-05-06 14:49:36 -07002876
Christoph Lameterf64dc582007-10-16 01:25:33 -07002877 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002878 struct kmem_cache_node *n;
2879
Alexander Duyck73367bd2010-05-21 14:41:35 -07002880 if (slab_state == DOWN) {
Christoph Lameter55136592010-08-20 12:37:13 -05002881 early_kmem_cache_node_alloc(node);
Alexander Duyck73367bd2010-05-21 14:41:35 -07002882 continue;
Christoph Lameter81819f02007-05-06 14:49:36 -07002883 }
Christoph Lameter51df1142010-08-20 12:37:15 -05002884 n = kmem_cache_alloc_node(kmem_cache_node,
Christoph Lameter55136592010-08-20 12:37:13 -05002885 GFP_KERNEL, node);
Alexander Duyck73367bd2010-05-21 14:41:35 -07002886
2887 if (!n) {
2888 free_kmem_cache_nodes(s);
2889 return 0;
2890 }
2891
Christoph Lameter81819f02007-05-06 14:49:36 -07002892 s->node[node] = n;
Pekka Enberg5595cff2008-08-05 09:28:47 +03002893 init_kmem_cache_node(n, s);
Christoph Lameter81819f02007-05-06 14:49:36 -07002894 }
2895 return 1;
2896}
Christoph Lameter81819f02007-05-06 14:49:36 -07002897
David Rientjesc0bdb232009-02-25 09:16:35 +02002898static void set_min_partial(struct kmem_cache *s, unsigned long min)
David Rientjes3b89d7d2009-02-22 17:40:07 -08002899{
2900 if (min < MIN_PARTIAL)
2901 min = MIN_PARTIAL;
2902 else if (min > MAX_PARTIAL)
2903 min = MAX_PARTIAL;
2904 s->min_partial = min;
2905}
2906
Christoph Lameter81819f02007-05-06 14:49:36 -07002907/*
2908 * calculate_sizes() determines the order and the distribution of data within
2909 * a slab object.
2910 */
Christoph Lameter06b285d2008-04-14 19:11:41 +03002911static int calculate_sizes(struct kmem_cache *s, int forced_order)
Christoph Lameter81819f02007-05-06 14:49:36 -07002912{
2913 unsigned long flags = s->flags;
2914 unsigned long size = s->objsize;
2915 unsigned long align = s->align;
Christoph Lameter834f3d12008-04-14 19:11:31 +03002916 int order;
Christoph Lameter81819f02007-05-06 14:49:36 -07002917
2918 /*
Christoph Lameterd8b42bf2008-02-15 23:45:25 -08002919 * Round up object size to the next word boundary. We can only
2920 * place the free pointer at word boundaries and this determines
2921 * the possible location of the free pointer.
2922 */
2923 size = ALIGN(size, sizeof(void *));
2924
2925#ifdef CONFIG_SLUB_DEBUG
2926 /*
Christoph Lameter81819f02007-05-06 14:49:36 -07002927 * Determine if we can poison the object itself. If the user of
2928 * the slab may touch the object after free or before allocation
2929 * then we should never poison the object itself.
2930 */
2931 if ((flags & SLAB_POISON) && !(flags & SLAB_DESTROY_BY_RCU) &&
Christoph Lameterc59def92007-05-16 22:10:50 -07002932 !s->ctor)
Christoph Lameter81819f02007-05-06 14:49:36 -07002933 s->flags |= __OBJECT_POISON;
2934 else
2935 s->flags &= ~__OBJECT_POISON;
2936
Christoph Lameter81819f02007-05-06 14:49:36 -07002937
2938 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07002939 * If we are Redzoning then check if there is some space between the
Christoph Lameter81819f02007-05-06 14:49:36 -07002940 * end of the object and the free pointer. If not then add an
Christoph Lameter672bba32007-05-09 02:32:39 -07002941 * additional word to have some bytes to store Redzone information.
Christoph Lameter81819f02007-05-06 14:49:36 -07002942 */
2943 if ((flags & SLAB_RED_ZONE) && size == s->objsize)
2944 size += sizeof(void *);
Christoph Lameter41ecc552007-05-09 02:32:44 -07002945#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07002946
2947 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07002948 * With that we have determined the number of bytes in actual use
2949 * by the object. This is the potential offset to the free pointer.
Christoph Lameter81819f02007-05-06 14:49:36 -07002950 */
2951 s->inuse = size;
2952
2953 if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) ||
Christoph Lameterc59def92007-05-16 22:10:50 -07002954 s->ctor)) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002955 /*
2956 * Relocate free pointer after the object if it is not
2957 * permitted to overwrite the first word of the object on
2958 * kmem_cache_free.
2959 *
2960 * This is the case if we do RCU, have a constructor or
2961 * destructor or are poisoning the objects.
2962 */
2963 s->offset = size;
2964 size += sizeof(void *);
2965 }
2966
Christoph Lameterc12b3c62007-05-23 13:57:31 -07002967#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter81819f02007-05-06 14:49:36 -07002968 if (flags & SLAB_STORE_USER)
2969 /*
2970 * Need to store information about allocs and frees after
2971 * the object.
2972 */
2973 size += 2 * sizeof(struct track);
2974
Christoph Lameterbe7b3fb2007-05-09 02:32:36 -07002975 if (flags & SLAB_RED_ZONE)
Christoph Lameter81819f02007-05-06 14:49:36 -07002976 /*
2977 * Add some empty padding so that we can catch
2978 * overwrites from earlier objects rather than let
2979 * tracking information or the free pointer be
Frederik Schwarzer0211a9c2008-12-29 22:14:56 +01002980 * corrupted if a user writes before the start
Christoph Lameter81819f02007-05-06 14:49:36 -07002981 * of the object.
2982 */
2983 size += sizeof(void *);
Christoph Lameter41ecc552007-05-09 02:32:44 -07002984#endif
Christoph Lameter672bba32007-05-09 02:32:39 -07002985
Christoph Lameter81819f02007-05-06 14:49:36 -07002986 /*
2987 * Determine the alignment based on various parameters that the
Christoph Lameter65c02d42007-05-09 02:32:35 -07002988 * user specified and the dynamic determination of cache line size
2989 * on bootup.
Christoph Lameter81819f02007-05-06 14:49:36 -07002990 */
2991 align = calculate_alignment(flags, align, s->objsize);
Zhang, Yanmindcb0ce12009-07-30 11:28:11 +08002992 s->align = align;
Christoph Lameter81819f02007-05-06 14:49:36 -07002993
2994 /*
2995 * SLUB stores one object immediately after another beginning from
2996 * offset 0. In order to align the objects we have to simply size
2997 * each object to conform to the alignment.
2998 */
2999 size = ALIGN(size, align);
3000 s->size = size;
Christoph Lameter06b285d2008-04-14 19:11:41 +03003001 if (forced_order >= 0)
3002 order = forced_order;
3003 else
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08003004 order = calculate_order(size, s->reserved);
Christoph Lameter81819f02007-05-06 14:49:36 -07003005
Christoph Lameter834f3d12008-04-14 19:11:31 +03003006 if (order < 0)
Christoph Lameter81819f02007-05-06 14:49:36 -07003007 return 0;
3008
Christoph Lameterb7a49f02008-02-14 14:21:32 -08003009 s->allocflags = 0;
Christoph Lameter834f3d12008-04-14 19:11:31 +03003010 if (order)
Christoph Lameterb7a49f02008-02-14 14:21:32 -08003011 s->allocflags |= __GFP_COMP;
3012
3013 if (s->flags & SLAB_CACHE_DMA)
3014 s->allocflags |= SLUB_DMA;
3015
3016 if (s->flags & SLAB_RECLAIM_ACCOUNT)
3017 s->allocflags |= __GFP_RECLAIMABLE;
3018
Christoph Lameter81819f02007-05-06 14:49:36 -07003019 /*
3020 * Determine the number of objects per slab
3021 */
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08003022 s->oo = oo_make(order, size, s->reserved);
3023 s->min = oo_make(get_order(size), size, s->reserved);
Christoph Lameter205ab992008-04-14 19:11:40 +03003024 if (oo_objects(s->oo) > oo_objects(s->max))
3025 s->max = s->oo;
Christoph Lameter81819f02007-05-06 14:49:36 -07003026
Christoph Lameter834f3d12008-04-14 19:11:31 +03003027 return !!oo_objects(s->oo);
Christoph Lameter81819f02007-05-06 14:49:36 -07003028
3029}
3030
Christoph Lameter55136592010-08-20 12:37:13 -05003031static int kmem_cache_open(struct kmem_cache *s,
Christoph Lameter81819f02007-05-06 14:49:36 -07003032 const char *name, size_t size,
3033 size_t align, unsigned long flags,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07003034 void (*ctor)(void *))
Christoph Lameter81819f02007-05-06 14:49:36 -07003035{
3036 memset(s, 0, kmem_size);
3037 s->name = name;
3038 s->ctor = ctor;
Christoph Lameter81819f02007-05-06 14:49:36 -07003039 s->objsize = size;
Christoph Lameter81819f02007-05-06 14:49:36 -07003040 s->align = align;
Christoph Lameterba0268a2007-09-11 15:24:11 -07003041 s->flags = kmem_cache_flags(size, flags, name, ctor);
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08003042 s->reserved = 0;
Christoph Lameter81819f02007-05-06 14:49:36 -07003043
Lai Jiangshanda9a6382011-03-10 15:22:00 +08003044 if (need_reserve_slab_rcu && (s->flags & SLAB_DESTROY_BY_RCU))
3045 s->reserved = sizeof(struct rcu_head);
Christoph Lameter81819f02007-05-06 14:49:36 -07003046
Christoph Lameter06b285d2008-04-14 19:11:41 +03003047 if (!calculate_sizes(s, -1))
Christoph Lameter81819f02007-05-06 14:49:36 -07003048 goto error;
David Rientjes3de47212009-07-27 18:30:35 -07003049 if (disable_higher_order_debug) {
3050 /*
3051 * Disable debugging flags that store metadata if the min slab
3052 * order increased.
3053 */
3054 if (get_order(s->size) > get_order(s->objsize)) {
3055 s->flags &= ~DEBUG_METADATA_FLAGS;
3056 s->offset = 0;
3057 if (!calculate_sizes(s, -1))
3058 goto error;
3059 }
3060 }
Christoph Lameter81819f02007-05-06 14:49:36 -07003061
Christoph Lameterb789ef52011-06-01 12:25:49 -05003062#ifdef CONFIG_CMPXCHG_DOUBLE
3063 if (system_has_cmpxchg_double() && (s->flags & SLAB_DEBUG_FLAGS) == 0)
3064 /* Enable fast mode */
3065 s->flags |= __CMPXCHG_DOUBLE;
3066#endif
3067
David Rientjes3b89d7d2009-02-22 17:40:07 -08003068 /*
3069 * The larger the object size is, the more pages we want on the partial
3070 * list to avoid pounding the page allocator excessively.
3071 */
Christoph Lameter49e22582011-08-09 16:12:27 -05003072 set_min_partial(s, ilog2(s->size) / 2);
3073
3074 /*
3075 * cpu_partial determined the maximum number of objects kept in the
3076 * per cpu partial lists of a processor.
3077 *
3078 * Per cpu partial lists mainly contain slabs that just have one
3079 * object freed. If they are used for allocation then they can be
3080 * filled up again with minimal effort. The slab will never hit the
3081 * per node partial lists and therefore no locking will be required.
3082 *
3083 * This setting also determines
3084 *
3085 * A) The number of objects from per cpu partial slabs dumped to the
3086 * per node list when we reach the limit.
3087 * B) The number of objects in partial partial slabs to extract from the
3088 * per node list when we run out of per cpu objects. We only fetch 50%
3089 * to keep some capacity around for frees.
3090 */
3091 if (s->size >= PAGE_SIZE)
3092 s->cpu_partial = 2;
3093 else if (s->size >= 1024)
3094 s->cpu_partial = 6;
3095 else if (s->size >= 256)
3096 s->cpu_partial = 13;
3097 else
3098 s->cpu_partial = 30;
3099
Christoph Lameter81819f02007-05-06 14:49:36 -07003100 s->refcount = 1;
3101#ifdef CONFIG_NUMA
Christoph Lametere2cb96b2008-08-19 08:51:22 -05003102 s->remote_node_defrag_ratio = 1000;
Christoph Lameter81819f02007-05-06 14:49:36 -07003103#endif
Christoph Lameter55136592010-08-20 12:37:13 -05003104 if (!init_kmem_cache_nodes(s))
Christoph Lameterdfb4f092007-10-16 01:26:05 -07003105 goto error;
Christoph Lameter81819f02007-05-06 14:49:36 -07003106
Christoph Lameter55136592010-08-20 12:37:13 -05003107 if (alloc_kmem_cache_cpus(s))
Christoph Lameter81819f02007-05-06 14:49:36 -07003108 return 1;
Christoph Lameterff120592009-12-18 16:26:22 -06003109
Christoph Lameter4c93c3552007-10-16 01:26:08 -07003110 free_kmem_cache_nodes(s);
Christoph Lameter81819f02007-05-06 14:49:36 -07003111error:
3112 if (flags & SLAB_PANIC)
3113 panic("Cannot create slab %s size=%lu realsize=%u "
3114 "order=%u offset=%u flags=%lx\n",
Christoph Lameter834f3d12008-04-14 19:11:31 +03003115 s->name, (unsigned long)size, s->size, oo_order(s->oo),
Christoph Lameter81819f02007-05-06 14:49:36 -07003116 s->offset, flags);
3117 return 0;
3118}
Christoph Lameter81819f02007-05-06 14:49:36 -07003119
3120/*
Christoph Lameter81819f02007-05-06 14:49:36 -07003121 * Determine the size of a slab object
3122 */
3123unsigned int kmem_cache_size(struct kmem_cache *s)
3124{
3125 return s->objsize;
3126}
3127EXPORT_SYMBOL(kmem_cache_size);
3128
Christoph Lameter33b12c32008-04-25 12:22:43 -07003129static void list_slab_objects(struct kmem_cache *s, struct page *page,
3130 const char *text)
Christoph Lameter81819f02007-05-06 14:49:36 -07003131{
Christoph Lameter33b12c32008-04-25 12:22:43 -07003132#ifdef CONFIG_SLUB_DEBUG
3133 void *addr = page_address(page);
3134 void *p;
Namhyung Kima5dd5c12010-09-29 21:02:13 +09003135 unsigned long *map = kzalloc(BITS_TO_LONGS(page->objects) *
3136 sizeof(long), GFP_ATOMIC);
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003137 if (!map)
3138 return;
Christoph Lameter33b12c32008-04-25 12:22:43 -07003139 slab_err(s, page, "%s", text);
3140 slab_lock(page);
Christoph Lameter33b12c32008-04-25 12:22:43 -07003141
Christoph Lameter5f80b132011-04-15 14:48:13 -05003142 get_map(s, page, map);
Christoph Lameter33b12c32008-04-25 12:22:43 -07003143 for_each_object(p, s, addr, page->objects) {
3144
3145 if (!test_bit(slab_index(p, s, addr), map)) {
3146 printk(KERN_ERR "INFO: Object 0x%p @offset=%tu\n",
3147 p, p - addr);
3148 print_tracking(s, p);
3149 }
3150 }
3151 slab_unlock(page);
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003152 kfree(map);
Christoph Lameter33b12c32008-04-25 12:22:43 -07003153#endif
3154}
3155
Christoph Lameter81819f02007-05-06 14:49:36 -07003156/*
Christoph Lameter599870b2008-04-23 12:36:52 -07003157 * Attempt to free all partial slabs on a node.
Christoph Lameter69cb8e62011-08-09 16:12:22 -05003158 * This is called from kmem_cache_close(). We must be the last thread
3159 * using the cache and therefore we do not need to lock anymore.
Christoph Lameter81819f02007-05-06 14:49:36 -07003160 */
Christoph Lameter599870b2008-04-23 12:36:52 -07003161static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
Christoph Lameter81819f02007-05-06 14:49:36 -07003162{
Christoph Lameter81819f02007-05-06 14:49:36 -07003163 struct page *page, *h;
3164
Christoph Lameter33b12c32008-04-25 12:22:43 -07003165 list_for_each_entry_safe(page, h, &n->partial, lru) {
Christoph Lameter81819f02007-05-06 14:49:36 -07003166 if (!page->inuse) {
Christoph Lameter5cc6eee2011-06-01 12:25:50 -05003167 remove_partial(n, page);
Christoph Lameter81819f02007-05-06 14:49:36 -07003168 discard_slab(s, page);
Christoph Lameter33b12c32008-04-25 12:22:43 -07003169 } else {
3170 list_slab_objects(s, page,
3171 "Objects remaining on kmem_cache_close()");
Christoph Lameter599870b2008-04-23 12:36:52 -07003172 }
Christoph Lameter33b12c32008-04-25 12:22:43 -07003173 }
Christoph Lameter81819f02007-05-06 14:49:36 -07003174}
3175
3176/*
Christoph Lameter672bba32007-05-09 02:32:39 -07003177 * Release all resources used by a slab cache.
Christoph Lameter81819f02007-05-06 14:49:36 -07003178 */
Christoph Lameter0c710012007-07-17 04:03:24 -07003179static inline int kmem_cache_close(struct kmem_cache *s)
Christoph Lameter81819f02007-05-06 14:49:36 -07003180{
3181 int node;
3182
3183 flush_all(s);
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06003184 free_percpu(s->cpu_slab);
Christoph Lameter81819f02007-05-06 14:49:36 -07003185 /* Attempt to free all objects */
Christoph Lameterf64dc582007-10-16 01:25:33 -07003186 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter81819f02007-05-06 14:49:36 -07003187 struct kmem_cache_node *n = get_node(s, node);
3188
Christoph Lameter599870b2008-04-23 12:36:52 -07003189 free_partial(s, n);
3190 if (n->nr_partial || slabs_node(s, node))
Christoph Lameter81819f02007-05-06 14:49:36 -07003191 return 1;
3192 }
3193 free_kmem_cache_nodes(s);
3194 return 0;
3195}
3196
3197/*
3198 * Close a cache and release the kmem_cache structure
3199 * (must be used for caches created using kmem_cache_create)
3200 */
3201void kmem_cache_destroy(struct kmem_cache *s)
3202{
3203 down_write(&slub_lock);
3204 s->refcount--;
3205 if (!s->refcount) {
3206 list_del(&s->list);
Christoph Lameter69cb8e62011-08-09 16:12:22 -05003207 up_write(&slub_lock);
Pekka Enbergd629d812008-04-23 22:31:08 +03003208 if (kmem_cache_close(s)) {
3209 printk(KERN_ERR "SLUB %s: %s called for cache that "
3210 "still has objects.\n", s->name, __func__);
3211 dump_stack();
3212 }
Eric Dumazetd76b1592009-09-03 22:38:59 +03003213 if (s->flags & SLAB_DESTROY_BY_RCU)
3214 rcu_barrier();
Christoph Lameter81819f02007-05-06 14:49:36 -07003215 sysfs_slab_remove(s);
Christoph Lameter69cb8e62011-08-09 16:12:22 -05003216 } else
3217 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07003218}
3219EXPORT_SYMBOL(kmem_cache_destroy);
3220
3221/********************************************************************
3222 * Kmalloc subsystem
3223 *******************************************************************/
3224
Christoph Lameter51df1142010-08-20 12:37:15 -05003225struct kmem_cache *kmalloc_caches[SLUB_PAGE_SHIFT];
Christoph Lameter81819f02007-05-06 14:49:36 -07003226EXPORT_SYMBOL(kmalloc_caches);
3227
Christoph Lameter51df1142010-08-20 12:37:15 -05003228static struct kmem_cache *kmem_cache;
3229
Christoph Lameter55136592010-08-20 12:37:13 -05003230#ifdef CONFIG_ZONE_DMA
Christoph Lameter51df1142010-08-20 12:37:15 -05003231static struct kmem_cache *kmalloc_dma_caches[SLUB_PAGE_SHIFT];
Christoph Lameter55136592010-08-20 12:37:13 -05003232#endif
3233
Christoph Lameter81819f02007-05-06 14:49:36 -07003234static int __init setup_slub_min_order(char *str)
3235{
Pekka Enberg06428782008-01-07 23:20:27 -08003236 get_option(&str, &slub_min_order);
Christoph Lameter81819f02007-05-06 14:49:36 -07003237
3238 return 1;
3239}
3240
3241__setup("slub_min_order=", setup_slub_min_order);
3242
3243static int __init setup_slub_max_order(char *str)
3244{
Pekka Enberg06428782008-01-07 23:20:27 -08003245 get_option(&str, &slub_max_order);
David Rientjes818cf592009-04-23 09:58:22 +03003246 slub_max_order = min(slub_max_order, MAX_ORDER - 1);
Christoph Lameter81819f02007-05-06 14:49:36 -07003247
3248 return 1;
3249}
3250
3251__setup("slub_max_order=", setup_slub_max_order);
3252
3253static int __init setup_slub_min_objects(char *str)
3254{
Pekka Enberg06428782008-01-07 23:20:27 -08003255 get_option(&str, &slub_min_objects);
Christoph Lameter81819f02007-05-06 14:49:36 -07003256
3257 return 1;
3258}
3259
3260__setup("slub_min_objects=", setup_slub_min_objects);
3261
3262static int __init setup_slub_nomerge(char *str)
3263{
3264 slub_nomerge = 1;
3265 return 1;
3266}
3267
3268__setup("slub_nomerge", setup_slub_nomerge);
3269
Christoph Lameter51df1142010-08-20 12:37:15 -05003270static struct kmem_cache *__init create_kmalloc_cache(const char *name,
3271 int size, unsigned int flags)
Christoph Lameter81819f02007-05-06 14:49:36 -07003272{
Christoph Lameter51df1142010-08-20 12:37:15 -05003273 struct kmem_cache *s;
3274
3275 s = kmem_cache_alloc(kmem_cache, GFP_NOWAIT);
3276
Pekka Enberg83b519e2009-06-10 19:40:04 +03003277 /*
3278 * This function is called with IRQs disabled during early-boot on
3279 * single CPU so there's no need to take slub_lock here.
3280 */
Christoph Lameter55136592010-08-20 12:37:13 -05003281 if (!kmem_cache_open(s, name, size, ARCH_KMALLOC_MINALIGN,
Christoph Lameter319d1e22008-04-14 19:11:41 +03003282 flags, NULL))
Christoph Lameter81819f02007-05-06 14:49:36 -07003283 goto panic;
3284
3285 list_add(&s->list, &slab_caches);
Christoph Lameter51df1142010-08-20 12:37:15 -05003286 return s;
Christoph Lameter81819f02007-05-06 14:49:36 -07003287
3288panic:
3289 panic("Creation of kmalloc slab %s size=%d failed.\n", name, size);
Christoph Lameter51df1142010-08-20 12:37:15 -05003290 return NULL;
Christoph Lameter81819f02007-05-06 14:49:36 -07003291}
3292
Christoph Lameterf1b26332007-07-17 04:03:26 -07003293/*
3294 * Conversion table for small slabs sizes / 8 to the index in the
3295 * kmalloc array. This is necessary for slabs < 192 since we have non power
3296 * of two cache sizes there. The size of larger slabs can be determined using
3297 * fls.
3298 */
3299static s8 size_index[24] = {
3300 3, /* 8 */
3301 4, /* 16 */
3302 5, /* 24 */
3303 5, /* 32 */
3304 6, /* 40 */
3305 6, /* 48 */
3306 6, /* 56 */
3307 6, /* 64 */
3308 1, /* 72 */
3309 1, /* 80 */
3310 1, /* 88 */
3311 1, /* 96 */
3312 7, /* 104 */
3313 7, /* 112 */
3314 7, /* 120 */
3315 7, /* 128 */
3316 2, /* 136 */
3317 2, /* 144 */
3318 2, /* 152 */
3319 2, /* 160 */
3320 2, /* 168 */
3321 2, /* 176 */
3322 2, /* 184 */
3323 2 /* 192 */
3324};
3325
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003326static inline int size_index_elem(size_t bytes)
3327{
3328 return (bytes - 1) / 8;
3329}
3330
Christoph Lameter81819f02007-05-06 14:49:36 -07003331static struct kmem_cache *get_slab(size_t size, gfp_t flags)
3332{
Christoph Lameterf1b26332007-07-17 04:03:26 -07003333 int index;
Christoph Lameter81819f02007-05-06 14:49:36 -07003334
Christoph Lameterf1b26332007-07-17 04:03:26 -07003335 if (size <= 192) {
3336 if (!size)
3337 return ZERO_SIZE_PTR;
Christoph Lameter81819f02007-05-06 14:49:36 -07003338
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003339 index = size_index[size_index_elem(size)];
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003340 } else
Christoph Lameterf1b26332007-07-17 04:03:26 -07003341 index = fls(size - 1);
Christoph Lameter81819f02007-05-06 14:49:36 -07003342
3343#ifdef CONFIG_ZONE_DMA
Christoph Lameterf1b26332007-07-17 04:03:26 -07003344 if (unlikely((flags & SLUB_DMA)))
Christoph Lameter51df1142010-08-20 12:37:15 -05003345 return kmalloc_dma_caches[index];
Christoph Lameterf1b26332007-07-17 04:03:26 -07003346
Christoph Lameter81819f02007-05-06 14:49:36 -07003347#endif
Christoph Lameter51df1142010-08-20 12:37:15 -05003348 return kmalloc_caches[index];
Christoph Lameter81819f02007-05-06 14:49:36 -07003349}
3350
3351void *__kmalloc(size_t size, gfp_t flags)
3352{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003353 struct kmem_cache *s;
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03003354 void *ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07003355
Christoph Lameterffadd4d2009-02-17 12:05:07 -05003356 if (unlikely(size > SLUB_MAX_SIZE))
Pekka Enbergeada35e2008-02-11 22:47:46 +02003357 return kmalloc_large(size, flags);
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003358
3359 s = get_slab(size, flags);
3360
3361 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07003362 return s;
3363
Christoph Lameter2154a332010-07-09 14:07:10 -05003364 ret = slab_alloc(s, flags, NUMA_NO_NODE, _RET_IP_);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03003365
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02003366 trace_kmalloc(_RET_IP_, ret, size, s->size, flags);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03003367
3368 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07003369}
3370EXPORT_SYMBOL(__kmalloc);
3371
Namhyung Kim5d1f57e2010-09-29 21:02:15 +09003372#ifdef CONFIG_NUMA
Christoph Lameterf619cfe2008-03-01 13:56:40 -08003373static void *kmalloc_large_node(size_t size, gfp_t flags, int node)
3374{
Vegard Nossumb1eeab62008-11-25 16:55:53 +01003375 struct page *page;
Catalin Marinase4f7c0b42009-07-07 10:32:59 +01003376 void *ptr = NULL;
Christoph Lameterf619cfe2008-03-01 13:56:40 -08003377
Vegard Nossumb1eeab62008-11-25 16:55:53 +01003378 flags |= __GFP_COMP | __GFP_NOTRACK;
3379 page = alloc_pages_node(node, flags, get_order(size));
Christoph Lameterf619cfe2008-03-01 13:56:40 -08003380 if (page)
Catalin Marinase4f7c0b42009-07-07 10:32:59 +01003381 ptr = page_address(page);
3382
3383 kmemleak_alloc(ptr, size, 1, flags);
3384 return ptr;
Christoph Lameterf619cfe2008-03-01 13:56:40 -08003385}
3386
Christoph Lameter81819f02007-05-06 14:49:36 -07003387void *__kmalloc_node(size_t size, gfp_t flags, int node)
3388{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003389 struct kmem_cache *s;
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03003390 void *ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07003391
Ingo Molnar057685c2009-02-20 12:15:30 +01003392 if (unlikely(size > SLUB_MAX_SIZE)) {
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03003393 ret = kmalloc_large_node(size, flags, node);
3394
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02003395 trace_kmalloc_node(_RET_IP_, ret,
3396 size, PAGE_SIZE << get_order(size),
3397 flags, node);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03003398
3399 return ret;
3400 }
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003401
3402 s = get_slab(size, flags);
3403
3404 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07003405 return s;
3406
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03003407 ret = slab_alloc(s, flags, node, _RET_IP_);
3408
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02003409 trace_kmalloc_node(_RET_IP_, ret, size, s->size, flags, node);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03003410
3411 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07003412}
3413EXPORT_SYMBOL(__kmalloc_node);
3414#endif
3415
3416size_t ksize(const void *object)
3417{
Christoph Lameter272c1d22007-06-08 13:46:49 -07003418 struct page *page;
Christoph Lameter81819f02007-05-06 14:49:36 -07003419
Christoph Lameteref8b4522007-10-16 01:24:46 -07003420 if (unlikely(object == ZERO_SIZE_PTR))
Christoph Lameter272c1d22007-06-08 13:46:49 -07003421 return 0;
3422
Vegard Nossum294a80a2007-12-04 23:45:30 -08003423 page = virt_to_head_page(object);
Vegard Nossum294a80a2007-12-04 23:45:30 -08003424
Pekka Enberg76994412008-05-22 19:22:25 +03003425 if (unlikely(!PageSlab(page))) {
3426 WARN_ON(!PageCompound(page));
Vegard Nossum294a80a2007-12-04 23:45:30 -08003427 return PAGE_SIZE << compound_order(page);
Pekka Enberg76994412008-05-22 19:22:25 +03003428 }
Christoph Lameter81819f02007-05-06 14:49:36 -07003429
Eric Dumazetb3d41882011-02-14 18:35:22 +01003430 return slab_ksize(page->slab);
Christoph Lameter81819f02007-05-06 14:49:36 -07003431}
Kirill A. Shutemovb1aabec2009-02-10 15:21:44 +02003432EXPORT_SYMBOL(ksize);
Christoph Lameter81819f02007-05-06 14:49:36 -07003433
Ben Greeard18a90d2011-07-07 11:36:37 -07003434#ifdef CONFIG_SLUB_DEBUG
3435bool verify_mem_not_deleted(const void *x)
3436{
3437 struct page *page;
3438 void *object = (void *)x;
3439 unsigned long flags;
3440 bool rv;
3441
3442 if (unlikely(ZERO_OR_NULL_PTR(x)))
3443 return false;
3444
3445 local_irq_save(flags);
3446
3447 page = virt_to_head_page(x);
3448 if (unlikely(!PageSlab(page))) {
3449 /* maybe it was from stack? */
3450 rv = true;
3451 goto out_unlock;
3452 }
3453
3454 slab_lock(page);
3455 if (on_freelist(page->slab, page, object)) {
3456 object_err(page->slab, page, object, "Object is on free-list");
3457 rv = false;
3458 } else {
3459 rv = true;
3460 }
3461 slab_unlock(page);
3462
3463out_unlock:
3464 local_irq_restore(flags);
3465 return rv;
3466}
3467EXPORT_SYMBOL(verify_mem_not_deleted);
3468#endif
3469
Christoph Lameter81819f02007-05-06 14:49:36 -07003470void kfree(const void *x)
3471{
Christoph Lameter81819f02007-05-06 14:49:36 -07003472 struct page *page;
Christoph Lameter5bb983b2008-02-07 17:47:41 -08003473 void *object = (void *)x;
Christoph Lameter81819f02007-05-06 14:49:36 -07003474
Pekka Enberg2121db72009-03-25 11:05:57 +02003475 trace_kfree(_RET_IP_, x);
3476
Satyam Sharma2408c552007-10-16 01:24:44 -07003477 if (unlikely(ZERO_OR_NULL_PTR(x)))
Christoph Lameter81819f02007-05-06 14:49:36 -07003478 return;
3479
Christoph Lameterb49af682007-05-06 14:49:41 -07003480 page = virt_to_head_page(x);
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003481 if (unlikely(!PageSlab(page))) {
Christoph Lameter09375022008-05-28 10:32:22 -07003482 BUG_ON(!PageCompound(page));
Catalin Marinase4f7c0b42009-07-07 10:32:59 +01003483 kmemleak_free(x);
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003484 put_page(page);
3485 return;
3486 }
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03003487 slab_free(page->slab, page, object, _RET_IP_);
Christoph Lameter81819f02007-05-06 14:49:36 -07003488}
3489EXPORT_SYMBOL(kfree);
3490
Christoph Lameter2086d262007-05-06 14:49:46 -07003491/*
Christoph Lameter672bba32007-05-09 02:32:39 -07003492 * kmem_cache_shrink removes empty slabs from the partial lists and sorts
3493 * the remaining slabs by the number of items in use. The slabs with the
3494 * most items in use come first. New allocations will then fill those up
3495 * and thus they can be removed from the partial lists.
3496 *
3497 * The slabs with the least items are placed last. This results in them
3498 * being allocated from last increasing the chance that the last objects
3499 * are freed in them.
Christoph Lameter2086d262007-05-06 14:49:46 -07003500 */
3501int kmem_cache_shrink(struct kmem_cache *s)
3502{
3503 int node;
3504 int i;
3505 struct kmem_cache_node *n;
3506 struct page *page;
3507 struct page *t;
Christoph Lameter205ab992008-04-14 19:11:40 +03003508 int objects = oo_objects(s->max);
Christoph Lameter2086d262007-05-06 14:49:46 -07003509 struct list_head *slabs_by_inuse =
Christoph Lameter834f3d12008-04-14 19:11:31 +03003510 kmalloc(sizeof(struct list_head) * objects, GFP_KERNEL);
Christoph Lameter2086d262007-05-06 14:49:46 -07003511 unsigned long flags;
3512
3513 if (!slabs_by_inuse)
3514 return -ENOMEM;
3515
3516 flush_all(s);
Christoph Lameterf64dc582007-10-16 01:25:33 -07003517 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter2086d262007-05-06 14:49:46 -07003518 n = get_node(s, node);
3519
3520 if (!n->nr_partial)
3521 continue;
3522
Christoph Lameter834f3d12008-04-14 19:11:31 +03003523 for (i = 0; i < objects; i++)
Christoph Lameter2086d262007-05-06 14:49:46 -07003524 INIT_LIST_HEAD(slabs_by_inuse + i);
3525
3526 spin_lock_irqsave(&n->list_lock, flags);
3527
3528 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07003529 * Build lists indexed by the items in use in each slab.
Christoph Lameter2086d262007-05-06 14:49:46 -07003530 *
Christoph Lameter672bba32007-05-09 02:32:39 -07003531 * Note that concurrent frees may occur while we hold the
3532 * list_lock. page->inuse here is the upper limit.
Christoph Lameter2086d262007-05-06 14:49:46 -07003533 */
3534 list_for_each_entry_safe(page, t, &n->partial, lru) {
Christoph Lameter69cb8e62011-08-09 16:12:22 -05003535 list_move(&page->lru, slabs_by_inuse + page->inuse);
3536 if (!page->inuse)
3537 n->nr_partial--;
Christoph Lameter2086d262007-05-06 14:49:46 -07003538 }
3539
Christoph Lameter2086d262007-05-06 14:49:46 -07003540 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07003541 * Rebuild the partial list with the slabs filled up most
3542 * first and the least used slabs at the end.
Christoph Lameter2086d262007-05-06 14:49:46 -07003543 */
Christoph Lameter69cb8e62011-08-09 16:12:22 -05003544 for (i = objects - 1; i > 0; i--)
Christoph Lameter2086d262007-05-06 14:49:46 -07003545 list_splice(slabs_by_inuse + i, n->partial.prev);
3546
Christoph Lameter2086d262007-05-06 14:49:46 -07003547 spin_unlock_irqrestore(&n->list_lock, flags);
Christoph Lameter69cb8e62011-08-09 16:12:22 -05003548
3549 /* Release empty slabs */
3550 list_for_each_entry_safe(page, t, slabs_by_inuse, lru)
3551 discard_slab(s, page);
Christoph Lameter2086d262007-05-06 14:49:46 -07003552 }
3553
3554 kfree(slabs_by_inuse);
3555 return 0;
3556}
3557EXPORT_SYMBOL(kmem_cache_shrink);
3558
Pekka Enberg92a5bbc2010-10-06 16:58:16 +03003559#if defined(CONFIG_MEMORY_HOTPLUG)
Yasunori Gotob9049e22007-10-21 16:41:37 -07003560static int slab_mem_going_offline_callback(void *arg)
3561{
3562 struct kmem_cache *s;
3563
3564 down_read(&slub_lock);
3565 list_for_each_entry(s, &slab_caches, list)
3566 kmem_cache_shrink(s);
3567 up_read(&slub_lock);
3568
3569 return 0;
3570}
3571
3572static void slab_mem_offline_callback(void *arg)
3573{
3574 struct kmem_cache_node *n;
3575 struct kmem_cache *s;
3576 struct memory_notify *marg = arg;
3577 int offline_node;
3578
3579 offline_node = marg->status_change_nid;
3580
3581 /*
3582 * If the node still has available memory. we need kmem_cache_node
3583 * for it yet.
3584 */
3585 if (offline_node < 0)
3586 return;
3587
3588 down_read(&slub_lock);
3589 list_for_each_entry(s, &slab_caches, list) {
3590 n = get_node(s, offline_node);
3591 if (n) {
3592 /*
3593 * if n->nr_slabs > 0, slabs still exist on the node
3594 * that is going down. We were unable to free them,
Adam Buchbinderc9404c92009-12-18 15:40:42 -05003595 * and offline_pages() function shouldn't call this
Yasunori Gotob9049e22007-10-21 16:41:37 -07003596 * callback. So, we must fail.
3597 */
Christoph Lameter0f389ec2008-04-14 18:53:02 +03003598 BUG_ON(slabs_node(s, offline_node));
Yasunori Gotob9049e22007-10-21 16:41:37 -07003599
3600 s->node[offline_node] = NULL;
Christoph Lameter8de66a02010-08-25 14:51:14 -05003601 kmem_cache_free(kmem_cache_node, n);
Yasunori Gotob9049e22007-10-21 16:41:37 -07003602 }
3603 }
3604 up_read(&slub_lock);
3605}
3606
3607static int slab_mem_going_online_callback(void *arg)
3608{
3609 struct kmem_cache_node *n;
3610 struct kmem_cache *s;
3611 struct memory_notify *marg = arg;
3612 int nid = marg->status_change_nid;
3613 int ret = 0;
3614
3615 /*
3616 * If the node's memory is already available, then kmem_cache_node is
3617 * already created. Nothing to do.
3618 */
3619 if (nid < 0)
3620 return 0;
3621
3622 /*
Christoph Lameter0121c6192008-04-29 16:11:12 -07003623 * We are bringing a node online. No memory is available yet. We must
Yasunori Gotob9049e22007-10-21 16:41:37 -07003624 * allocate a kmem_cache_node structure in order to bring the node
3625 * online.
3626 */
3627 down_read(&slub_lock);
3628 list_for_each_entry(s, &slab_caches, list) {
3629 /*
3630 * XXX: kmem_cache_alloc_node will fallback to other nodes
3631 * since memory is not yet available from the node that
3632 * is brought up.
3633 */
Christoph Lameter8de66a02010-08-25 14:51:14 -05003634 n = kmem_cache_alloc(kmem_cache_node, GFP_KERNEL);
Yasunori Gotob9049e22007-10-21 16:41:37 -07003635 if (!n) {
3636 ret = -ENOMEM;
3637 goto out;
3638 }
Pekka Enberg5595cff2008-08-05 09:28:47 +03003639 init_kmem_cache_node(n, s);
Yasunori Gotob9049e22007-10-21 16:41:37 -07003640 s->node[nid] = n;
3641 }
3642out:
3643 up_read(&slub_lock);
3644 return ret;
3645}
3646
3647static int slab_memory_callback(struct notifier_block *self,
3648 unsigned long action, void *arg)
3649{
3650 int ret = 0;
3651
3652 switch (action) {
3653 case MEM_GOING_ONLINE:
3654 ret = slab_mem_going_online_callback(arg);
3655 break;
3656 case MEM_GOING_OFFLINE:
3657 ret = slab_mem_going_offline_callback(arg);
3658 break;
3659 case MEM_OFFLINE:
3660 case MEM_CANCEL_ONLINE:
3661 slab_mem_offline_callback(arg);
3662 break;
3663 case MEM_ONLINE:
3664 case MEM_CANCEL_OFFLINE:
3665 break;
3666 }
KAMEZAWA Hiroyukidc19f9d2008-12-01 13:13:48 -08003667 if (ret)
3668 ret = notifier_from_errno(ret);
3669 else
3670 ret = NOTIFY_OK;
Yasunori Gotob9049e22007-10-21 16:41:37 -07003671 return ret;
3672}
3673
3674#endif /* CONFIG_MEMORY_HOTPLUG */
3675
Christoph Lameter81819f02007-05-06 14:49:36 -07003676/********************************************************************
3677 * Basic setup of slabs
3678 *******************************************************************/
3679
Christoph Lameter51df1142010-08-20 12:37:15 -05003680/*
3681 * Used for early kmem_cache structures that were allocated using
3682 * the page allocator
3683 */
3684
3685static void __init kmem_cache_bootstrap_fixup(struct kmem_cache *s)
3686{
3687 int node;
3688
3689 list_add(&s->list, &slab_caches);
3690 s->refcount = -1;
3691
3692 for_each_node_state(node, N_NORMAL_MEMORY) {
3693 struct kmem_cache_node *n = get_node(s, node);
3694 struct page *p;
3695
3696 if (n) {
3697 list_for_each_entry(p, &n->partial, lru)
3698 p->slab = s;
3699
Li Zefan607bf322011-04-12 15:22:26 +08003700#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter51df1142010-08-20 12:37:15 -05003701 list_for_each_entry(p, &n->full, lru)
3702 p->slab = s;
3703#endif
3704 }
3705 }
3706}
3707
Christoph Lameter81819f02007-05-06 14:49:36 -07003708void __init kmem_cache_init(void)
3709{
3710 int i;
Christoph Lameter4b356be2007-06-16 10:16:13 -07003711 int caches = 0;
Christoph Lameter51df1142010-08-20 12:37:15 -05003712 struct kmem_cache *temp_kmem_cache;
3713 int order;
Christoph Lameter51df1142010-08-20 12:37:15 -05003714 struct kmem_cache *temp_kmem_cache_node;
3715 unsigned long kmalloc_size;
3716
3717 kmem_size = offsetof(struct kmem_cache, node) +
3718 nr_node_ids * sizeof(struct kmem_cache_node *);
3719
3720 /* Allocate two kmem_caches from the page allocator */
3721 kmalloc_size = ALIGN(kmem_size, cache_line_size());
3722 order = get_order(2 * kmalloc_size);
3723 kmem_cache = (void *)__get_free_pages(GFP_NOWAIT, order);
3724
Christoph Lameter81819f02007-05-06 14:49:36 -07003725 /*
3726 * Must first have the slab cache available for the allocations of the
Christoph Lameter672bba32007-05-09 02:32:39 -07003727 * struct kmem_cache_node's. There is special bootstrap code in
Christoph Lameter81819f02007-05-06 14:49:36 -07003728 * kmem_cache_open for slab_state == DOWN.
3729 */
Christoph Lameter51df1142010-08-20 12:37:15 -05003730 kmem_cache_node = (void *)kmem_cache + kmalloc_size;
3731
3732 kmem_cache_open(kmem_cache_node, "kmem_cache_node",
3733 sizeof(struct kmem_cache_node),
3734 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
Yasunori Gotob9049e22007-10-21 16:41:37 -07003735
Nadia Derbey0c40ba42008-04-29 01:00:41 -07003736 hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI);
Christoph Lameter81819f02007-05-06 14:49:36 -07003737
3738 /* Able to allocate the per node structures */
3739 slab_state = PARTIAL;
3740
Christoph Lameter51df1142010-08-20 12:37:15 -05003741 temp_kmem_cache = kmem_cache;
3742 kmem_cache_open(kmem_cache, "kmem_cache", kmem_size,
3743 0, SLAB_HWCACHE_ALIGN | SLAB_PANIC, NULL);
3744 kmem_cache = kmem_cache_alloc(kmem_cache, GFP_NOWAIT);
3745 memcpy(kmem_cache, temp_kmem_cache, kmem_size);
Christoph Lameter81819f02007-05-06 14:49:36 -07003746
Christoph Lameter51df1142010-08-20 12:37:15 -05003747 /*
3748 * Allocate kmem_cache_node properly from the kmem_cache slab.
3749 * kmem_cache_node is separately allocated so no need to
3750 * update any list pointers.
3751 */
3752 temp_kmem_cache_node = kmem_cache_node;
Christoph Lameter81819f02007-05-06 14:49:36 -07003753
Christoph Lameter51df1142010-08-20 12:37:15 -05003754 kmem_cache_node = kmem_cache_alloc(kmem_cache, GFP_NOWAIT);
3755 memcpy(kmem_cache_node, temp_kmem_cache_node, kmem_size);
3756
3757 kmem_cache_bootstrap_fixup(kmem_cache_node);
3758
3759 caches++;
Christoph Lameter51df1142010-08-20 12:37:15 -05003760 kmem_cache_bootstrap_fixup(kmem_cache);
3761 caches++;
3762 /* Free temporary boot structure */
3763 free_pages((unsigned long)temp_kmem_cache, order);
3764
3765 /* Now we can use the kmem_cache to allocate kmalloc slabs */
Christoph Lameterf1b26332007-07-17 04:03:26 -07003766
3767 /*
3768 * Patch up the size_index table if we have strange large alignment
3769 * requirements for the kmalloc array. This is only the case for
Christoph Lameter6446faa2008-02-15 23:45:26 -08003770 * MIPS it seems. The standard arches will not generate any code here.
Christoph Lameterf1b26332007-07-17 04:03:26 -07003771 *
3772 * Largest permitted alignment is 256 bytes due to the way we
3773 * handle the index determination for the smaller caches.
3774 *
3775 * Make sure that nothing crazy happens if someone starts tinkering
3776 * around with ARCH_KMALLOC_MINALIGN
3777 */
3778 BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 ||
3779 (KMALLOC_MIN_SIZE & (KMALLOC_MIN_SIZE - 1)));
3780
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003781 for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) {
3782 int elem = size_index_elem(i);
3783 if (elem >= ARRAY_SIZE(size_index))
3784 break;
3785 size_index[elem] = KMALLOC_SHIFT_LOW;
3786 }
Christoph Lameterf1b26332007-07-17 04:03:26 -07003787
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003788 if (KMALLOC_MIN_SIZE == 64) {
3789 /*
3790 * The 96 byte size cache is not used if the alignment
3791 * is 64 byte.
3792 */
3793 for (i = 64 + 8; i <= 96; i += 8)
3794 size_index[size_index_elem(i)] = 7;
3795 } else if (KMALLOC_MIN_SIZE == 128) {
Christoph Lameter41d54d32008-07-03 09:14:26 -05003796 /*
3797 * The 192 byte sized cache is not used if the alignment
3798 * is 128 byte. Redirect kmalloc to use the 256 byte cache
3799 * instead.
3800 */
3801 for (i = 128 + 8; i <= 192; i += 8)
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003802 size_index[size_index_elem(i)] = 8;
Christoph Lameter41d54d32008-07-03 09:14:26 -05003803 }
3804
Christoph Lameter51df1142010-08-20 12:37:15 -05003805 /* Caches that are not of the two-to-the-power-of size */
3806 if (KMALLOC_MIN_SIZE <= 32) {
3807 kmalloc_caches[1] = create_kmalloc_cache("kmalloc-96", 96, 0);
3808 caches++;
3809 }
3810
3811 if (KMALLOC_MIN_SIZE <= 64) {
3812 kmalloc_caches[2] = create_kmalloc_cache("kmalloc-192", 192, 0);
3813 caches++;
3814 }
3815
3816 for (i = KMALLOC_SHIFT_LOW; i < SLUB_PAGE_SHIFT; i++) {
3817 kmalloc_caches[i] = create_kmalloc_cache("kmalloc", 1 << i, 0);
3818 caches++;
3819 }
3820
Christoph Lameter81819f02007-05-06 14:49:36 -07003821 slab_state = UP;
3822
3823 /* Provide the correct kmalloc names now that the caches are up */
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003824 if (KMALLOC_MIN_SIZE <= 32) {
3825 kmalloc_caches[1]->name = kstrdup(kmalloc_caches[1]->name, GFP_NOWAIT);
3826 BUG_ON(!kmalloc_caches[1]->name);
3827 }
3828
3829 if (KMALLOC_MIN_SIZE <= 64) {
3830 kmalloc_caches[2]->name = kstrdup(kmalloc_caches[2]->name, GFP_NOWAIT);
3831 BUG_ON(!kmalloc_caches[2]->name);
3832 }
3833
Christoph Lameterd7278bd2010-07-09 14:07:12 -05003834 for (i = KMALLOC_SHIFT_LOW; i < SLUB_PAGE_SHIFT; i++) {
3835 char *s = kasprintf(GFP_NOWAIT, "kmalloc-%d", 1 << i);
3836
3837 BUG_ON(!s);
Christoph Lameter51df1142010-08-20 12:37:15 -05003838 kmalloc_caches[i]->name = s;
Christoph Lameterd7278bd2010-07-09 14:07:12 -05003839 }
Christoph Lameter81819f02007-05-06 14:49:36 -07003840
3841#ifdef CONFIG_SMP
3842 register_cpu_notifier(&slab_notifier);
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06003843#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07003844
Christoph Lameter55136592010-08-20 12:37:13 -05003845#ifdef CONFIG_ZONE_DMA
Christoph Lameter51df1142010-08-20 12:37:15 -05003846 for (i = 0; i < SLUB_PAGE_SHIFT; i++) {
3847 struct kmem_cache *s = kmalloc_caches[i];
Christoph Lameter55136592010-08-20 12:37:13 -05003848
Christoph Lameter51df1142010-08-20 12:37:15 -05003849 if (s && s->size) {
Christoph Lameter55136592010-08-20 12:37:13 -05003850 char *name = kasprintf(GFP_NOWAIT,
3851 "dma-kmalloc-%d", s->objsize);
3852
3853 BUG_ON(!name);
Christoph Lameter51df1142010-08-20 12:37:15 -05003854 kmalloc_dma_caches[i] = create_kmalloc_cache(name,
3855 s->objsize, SLAB_CACHE_DMA);
Christoph Lameter55136592010-08-20 12:37:13 -05003856 }
3857 }
3858#endif
Ingo Molnar3adbefe2008-02-05 17:57:39 -08003859 printk(KERN_INFO
3860 "SLUB: Genslabs=%d, HWalign=%d, Order=%d-%d, MinObjects=%d,"
Christoph Lameter4b356be2007-06-16 10:16:13 -07003861 " CPUs=%d, Nodes=%d\n",
3862 caches, cache_line_size(),
Christoph Lameter81819f02007-05-06 14:49:36 -07003863 slub_min_order, slub_max_order, slub_min_objects,
3864 nr_cpu_ids, nr_node_ids);
3865}
3866
Pekka Enberg7e85ee02009-06-12 14:03:06 +03003867void __init kmem_cache_init_late(void)
3868{
Pekka Enberg7e85ee02009-06-12 14:03:06 +03003869}
3870
Christoph Lameter81819f02007-05-06 14:49:36 -07003871/*
3872 * Find a mergeable slab cache
3873 */
3874static int slab_unmergeable(struct kmem_cache *s)
3875{
3876 if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE))
3877 return 1;
3878
Christoph Lameterc59def92007-05-16 22:10:50 -07003879 if (s->ctor)
Christoph Lameter81819f02007-05-06 14:49:36 -07003880 return 1;
3881
Christoph Lameter8ffa6872007-05-31 00:40:51 -07003882 /*
3883 * We may have set a slab to be unmergeable during bootstrap.
3884 */
3885 if (s->refcount < 0)
3886 return 1;
3887
Christoph Lameter81819f02007-05-06 14:49:36 -07003888 return 0;
3889}
3890
3891static struct kmem_cache *find_mergeable(size_t size,
Christoph Lameterba0268a2007-09-11 15:24:11 -07003892 size_t align, unsigned long flags, const char *name,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07003893 void (*ctor)(void *))
Christoph Lameter81819f02007-05-06 14:49:36 -07003894{
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07003895 struct kmem_cache *s;
Christoph Lameter81819f02007-05-06 14:49:36 -07003896
3897 if (slub_nomerge || (flags & SLUB_NEVER_MERGE))
3898 return NULL;
3899
Christoph Lameterc59def92007-05-16 22:10:50 -07003900 if (ctor)
Christoph Lameter81819f02007-05-06 14:49:36 -07003901 return NULL;
3902
3903 size = ALIGN(size, sizeof(void *));
3904 align = calculate_alignment(flags, align, size);
3905 size = ALIGN(size, align);
Christoph Lameterba0268a2007-09-11 15:24:11 -07003906 flags = kmem_cache_flags(size, flags, name, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -07003907
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07003908 list_for_each_entry(s, &slab_caches, list) {
Christoph Lameter81819f02007-05-06 14:49:36 -07003909 if (slab_unmergeable(s))
3910 continue;
3911
3912 if (size > s->size)
3913 continue;
3914
Christoph Lameterba0268a2007-09-11 15:24:11 -07003915 if ((flags & SLUB_MERGE_SAME) != (s->flags & SLUB_MERGE_SAME))
Christoph Lameter81819f02007-05-06 14:49:36 -07003916 continue;
3917 /*
3918 * Check if alignment is compatible.
3919 * Courtesy of Adrian Drzewiecki
3920 */
Pekka Enberg06428782008-01-07 23:20:27 -08003921 if ((s->size & ~(align - 1)) != s->size)
Christoph Lameter81819f02007-05-06 14:49:36 -07003922 continue;
3923
3924 if (s->size - size >= sizeof(void *))
3925 continue;
3926
3927 return s;
3928 }
3929 return NULL;
3930}
3931
3932struct kmem_cache *kmem_cache_create(const char *name, size_t size,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07003933 size_t align, unsigned long flags, void (*ctor)(void *))
Christoph Lameter81819f02007-05-06 14:49:36 -07003934{
3935 struct kmem_cache *s;
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003936 char *n;
Christoph Lameter81819f02007-05-06 14:49:36 -07003937
Benjamin Herrenschmidtfe1ff492009-09-21 17:02:30 -07003938 if (WARN_ON(!name))
3939 return NULL;
3940
Christoph Lameter81819f02007-05-06 14:49:36 -07003941 down_write(&slub_lock);
Christoph Lameterba0268a2007-09-11 15:24:11 -07003942 s = find_mergeable(size, align, flags, name, ctor);
Christoph Lameter81819f02007-05-06 14:49:36 -07003943 if (s) {
3944 s->refcount++;
3945 /*
3946 * Adjust the object sizes so that we clear
3947 * the complete object on kzalloc.
3948 */
3949 s->objsize = max(s->objsize, (int)size);
3950 s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *)));
Christoph Lameter6446faa2008-02-15 23:45:26 -08003951
David Rientjes7b8f3b62008-12-17 22:09:46 -08003952 if (sysfs_slab_alias(s, name)) {
David Rientjes7b8f3b62008-12-17 22:09:46 -08003953 s->refcount--;
Christoph Lameter81819f02007-05-06 14:49:36 -07003954 goto err;
David Rientjes7b8f3b62008-12-17 22:09:46 -08003955 }
Christoph Lameter2bce6482010-07-19 11:39:11 -05003956 up_write(&slub_lock);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003957 return s;
3958 }
Christoph Lameter6446faa2008-02-15 23:45:26 -08003959
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003960 n = kstrdup(name, GFP_KERNEL);
3961 if (!n)
3962 goto err;
3963
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003964 s = kmalloc(kmem_size, GFP_KERNEL);
3965 if (s) {
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003966 if (kmem_cache_open(s, n,
Christoph Lameterc59def92007-05-16 22:10:50 -07003967 size, align, flags, ctor)) {
Christoph Lameter81819f02007-05-06 14:49:36 -07003968 list_add(&s->list, &slab_caches);
David Rientjes7b8f3b62008-12-17 22:09:46 -08003969 if (sysfs_slab_add(s)) {
David Rientjes7b8f3b62008-12-17 22:09:46 -08003970 list_del(&s->list);
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003971 kfree(n);
David Rientjes7b8f3b62008-12-17 22:09:46 -08003972 kfree(s);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003973 goto err;
David Rientjes7b8f3b62008-12-17 22:09:46 -08003974 }
Christoph Lameter2bce6482010-07-19 11:39:11 -05003975 up_write(&slub_lock);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003976 return s;
3977 }
Pekka Enberg84c1cf62010-09-14 23:21:12 +03003978 kfree(n);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003979 kfree(s);
Christoph Lameter81819f02007-05-06 14:49:36 -07003980 }
Pavel Emelyanov68cee4f12010-10-28 13:50:37 +04003981err:
Christoph Lameter81819f02007-05-06 14:49:36 -07003982 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07003983
Christoph Lameter81819f02007-05-06 14:49:36 -07003984 if (flags & SLAB_PANIC)
3985 panic("Cannot create slabcache %s\n", name);
3986 else
3987 s = NULL;
3988 return s;
3989}
3990EXPORT_SYMBOL(kmem_cache_create);
3991
Christoph Lameter81819f02007-05-06 14:49:36 -07003992#ifdef CONFIG_SMP
Christoph Lameter27390bc2007-06-01 00:47:09 -07003993/*
Christoph Lameter672bba32007-05-09 02:32:39 -07003994 * Use the cpu notifier to insure that the cpu slabs are flushed when
3995 * necessary.
Christoph Lameter81819f02007-05-06 14:49:36 -07003996 */
3997static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
3998 unsigned long action, void *hcpu)
3999{
4000 long cpu = (long)hcpu;
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07004001 struct kmem_cache *s;
4002 unsigned long flags;
Christoph Lameter81819f02007-05-06 14:49:36 -07004003
4004 switch (action) {
4005 case CPU_UP_CANCELED:
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07004006 case CPU_UP_CANCELED_FROZEN:
Christoph Lameter81819f02007-05-06 14:49:36 -07004007 case CPU_DEAD:
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07004008 case CPU_DEAD_FROZEN:
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07004009 down_read(&slub_lock);
4010 list_for_each_entry(s, &slab_caches, list) {
4011 local_irq_save(flags);
4012 __flush_cpu_slab(s, cpu);
4013 local_irq_restore(flags);
4014 }
4015 up_read(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07004016 break;
4017 default:
4018 break;
4019 }
4020 return NOTIFY_OK;
4021}
4022
Pekka Enberg06428782008-01-07 23:20:27 -08004023static struct notifier_block __cpuinitdata slab_notifier = {
Ingo Molnar3adbefe2008-02-05 17:57:39 -08004024 .notifier_call = slab_cpuup_callback
Pekka Enberg06428782008-01-07 23:20:27 -08004025};
Christoph Lameter81819f02007-05-06 14:49:36 -07004026
4027#endif
4028
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03004029void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, unsigned long caller)
Christoph Lameter81819f02007-05-06 14:49:36 -07004030{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07004031 struct kmem_cache *s;
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03004032 void *ret;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07004033
Christoph Lameterffadd4d2009-02-17 12:05:07 -05004034 if (unlikely(size > SLUB_MAX_SIZE))
Pekka Enbergeada35e2008-02-11 22:47:46 +02004035 return kmalloc_large(size, gfpflags);
4036
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07004037 s = get_slab(size, gfpflags);
Christoph Lameter81819f02007-05-06 14:49:36 -07004038
Satyam Sharma2408c552007-10-16 01:24:44 -07004039 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07004040 return s;
Christoph Lameter81819f02007-05-06 14:49:36 -07004041
Christoph Lameter2154a332010-07-09 14:07:10 -05004042 ret = slab_alloc(s, gfpflags, NUMA_NO_NODE, caller);
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03004043
Lucas De Marchi25985ed2011-03-30 22:57:33 -03004044 /* Honor the call site pointer we received. */
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02004045 trace_kmalloc(caller, ret, size, s->size, gfpflags);
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03004046
4047 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07004048}
4049
Namhyung Kim5d1f57e2010-09-29 21:02:15 +09004050#ifdef CONFIG_NUMA
Christoph Lameter81819f02007-05-06 14:49:36 -07004051void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03004052 int node, unsigned long caller)
Christoph Lameter81819f02007-05-06 14:49:36 -07004053{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07004054 struct kmem_cache *s;
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03004055 void *ret;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07004056
Xiaotian Fengd3e14aa2010-04-08 17:26:44 +08004057 if (unlikely(size > SLUB_MAX_SIZE)) {
4058 ret = kmalloc_large_node(size, gfpflags, node);
4059
4060 trace_kmalloc_node(caller, ret,
4061 size, PAGE_SIZE << get_order(size),
4062 gfpflags, node);
4063
4064 return ret;
4065 }
Pekka Enbergeada35e2008-02-11 22:47:46 +02004066
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07004067 s = get_slab(size, gfpflags);
Christoph Lameter81819f02007-05-06 14:49:36 -07004068
Satyam Sharma2408c552007-10-16 01:24:44 -07004069 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07004070 return s;
Christoph Lameter81819f02007-05-06 14:49:36 -07004071
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03004072 ret = slab_alloc(s, gfpflags, node, caller);
4073
Lucas De Marchi25985ed2011-03-30 22:57:33 -03004074 /* Honor the call site pointer we received. */
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02004075 trace_kmalloc_node(caller, ret, size, s->size, gfpflags, node);
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03004076
4077 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07004078}
Namhyung Kim5d1f57e2010-09-29 21:02:15 +09004079#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07004080
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004081#ifdef CONFIG_SYSFS
Christoph Lameter205ab992008-04-14 19:11:40 +03004082static int count_inuse(struct page *page)
4083{
4084 return page->inuse;
4085}
4086
4087static int count_total(struct page *page)
4088{
4089 return page->objects;
4090}
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004091#endif
Christoph Lameter205ab992008-04-14 19:11:40 +03004092
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004093#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter434e2452007-07-17 04:03:30 -07004094static int validate_slab(struct kmem_cache *s, struct page *page,
4095 unsigned long *map)
Christoph Lameter53e15af2007-05-06 14:49:43 -07004096{
4097 void *p;
Christoph Lametera973e9d2008-03-01 13:40:44 -08004098 void *addr = page_address(page);
Christoph Lameter53e15af2007-05-06 14:49:43 -07004099
4100 if (!check_slab(s, page) ||
4101 !on_freelist(s, page, NULL))
4102 return 0;
4103
4104 /* Now we know that a valid freelist exists */
Christoph Lameter39b26462008-04-14 19:11:30 +03004105 bitmap_zero(map, page->objects);
Christoph Lameter53e15af2007-05-06 14:49:43 -07004106
Christoph Lameter5f80b132011-04-15 14:48:13 -05004107 get_map(s, page, map);
4108 for_each_object(p, s, addr, page->objects) {
4109 if (test_bit(slab_index(p, s, addr), map))
4110 if (!check_object(s, page, p, SLUB_RED_INACTIVE))
4111 return 0;
Christoph Lameter53e15af2007-05-06 14:49:43 -07004112 }
4113
Christoph Lameter224a88b2008-04-14 19:11:31 +03004114 for_each_object(p, s, addr, page->objects)
Christoph Lameter7656c722007-05-09 02:32:40 -07004115 if (!test_bit(slab_index(p, s, addr), map))
Tero Roponen37d57442010-12-01 20:04:20 +02004116 if (!check_object(s, page, p, SLUB_RED_ACTIVE))
Christoph Lameter53e15af2007-05-06 14:49:43 -07004117 return 0;
4118 return 1;
4119}
4120
Christoph Lameter434e2452007-07-17 04:03:30 -07004121static void validate_slab_slab(struct kmem_cache *s, struct page *page,
4122 unsigned long *map)
Christoph Lameter53e15af2007-05-06 14:49:43 -07004123{
Christoph Lameter881db7f2011-06-01 12:25:53 -05004124 slab_lock(page);
4125 validate_slab(s, page, map);
4126 slab_unlock(page);
Christoph Lameter53e15af2007-05-06 14:49:43 -07004127}
4128
Christoph Lameter434e2452007-07-17 04:03:30 -07004129static int validate_slab_node(struct kmem_cache *s,
4130 struct kmem_cache_node *n, unsigned long *map)
Christoph Lameter53e15af2007-05-06 14:49:43 -07004131{
4132 unsigned long count = 0;
4133 struct page *page;
4134 unsigned long flags;
4135
4136 spin_lock_irqsave(&n->list_lock, flags);
4137
4138 list_for_each_entry(page, &n->partial, lru) {
Christoph Lameter434e2452007-07-17 04:03:30 -07004139 validate_slab_slab(s, page, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07004140 count++;
4141 }
4142 if (count != n->nr_partial)
4143 printk(KERN_ERR "SLUB %s: %ld partial slabs counted but "
4144 "counter=%ld\n", s->name, count, n->nr_partial);
4145
4146 if (!(s->flags & SLAB_STORE_USER))
4147 goto out;
4148
4149 list_for_each_entry(page, &n->full, lru) {
Christoph Lameter434e2452007-07-17 04:03:30 -07004150 validate_slab_slab(s, page, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07004151 count++;
4152 }
4153 if (count != atomic_long_read(&n->nr_slabs))
4154 printk(KERN_ERR "SLUB: %s %ld slabs counted but "
4155 "counter=%ld\n", s->name, count,
4156 atomic_long_read(&n->nr_slabs));
4157
4158out:
4159 spin_unlock_irqrestore(&n->list_lock, flags);
4160 return count;
4161}
4162
Christoph Lameter434e2452007-07-17 04:03:30 -07004163static long validate_slab_cache(struct kmem_cache *s)
Christoph Lameter53e15af2007-05-06 14:49:43 -07004164{
4165 int node;
4166 unsigned long count = 0;
Christoph Lameter205ab992008-04-14 19:11:40 +03004167 unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
Christoph Lameter434e2452007-07-17 04:03:30 -07004168 sizeof(unsigned long), GFP_KERNEL);
4169
4170 if (!map)
4171 return -ENOMEM;
Christoph Lameter53e15af2007-05-06 14:49:43 -07004172
4173 flush_all(s);
Christoph Lameterf64dc582007-10-16 01:25:33 -07004174 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter53e15af2007-05-06 14:49:43 -07004175 struct kmem_cache_node *n = get_node(s, node);
4176
Christoph Lameter434e2452007-07-17 04:03:30 -07004177 count += validate_slab_node(s, n, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07004178 }
Christoph Lameter434e2452007-07-17 04:03:30 -07004179 kfree(map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07004180 return count;
4181}
Christoph Lameter88a420e2007-05-06 14:49:45 -07004182/*
Christoph Lameter672bba32007-05-09 02:32:39 -07004183 * Generate lists of code addresses where slabcache objects are allocated
Christoph Lameter88a420e2007-05-06 14:49:45 -07004184 * and freed.
4185 */
4186
4187struct location {
4188 unsigned long count;
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03004189 unsigned long addr;
Christoph Lameter45edfa52007-05-09 02:32:45 -07004190 long long sum_time;
4191 long min_time;
4192 long max_time;
4193 long min_pid;
4194 long max_pid;
Rusty Russell174596a2009-01-01 10:12:29 +10304195 DECLARE_BITMAP(cpus, NR_CPUS);
Christoph Lameter45edfa52007-05-09 02:32:45 -07004196 nodemask_t nodes;
Christoph Lameter88a420e2007-05-06 14:49:45 -07004197};
4198
4199struct loc_track {
4200 unsigned long max;
4201 unsigned long count;
4202 struct location *loc;
4203};
4204
4205static void free_loc_track(struct loc_track *t)
4206{
4207 if (t->max)
4208 free_pages((unsigned long)t->loc,
4209 get_order(sizeof(struct location) * t->max));
4210}
4211
Christoph Lameter68dff6a2007-07-17 04:03:20 -07004212static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags)
Christoph Lameter88a420e2007-05-06 14:49:45 -07004213{
4214 struct location *l;
4215 int order;
4216
Christoph Lameter88a420e2007-05-06 14:49:45 -07004217 order = get_order(sizeof(struct location) * max);
4218
Christoph Lameter68dff6a2007-07-17 04:03:20 -07004219 l = (void *)__get_free_pages(flags, order);
Christoph Lameter88a420e2007-05-06 14:49:45 -07004220 if (!l)
4221 return 0;
4222
4223 if (t->count) {
4224 memcpy(l, t->loc, sizeof(struct location) * t->count);
4225 free_loc_track(t);
4226 }
4227 t->max = max;
4228 t->loc = l;
4229 return 1;
4230}
4231
4232static int add_location(struct loc_track *t, struct kmem_cache *s,
Christoph Lameter45edfa52007-05-09 02:32:45 -07004233 const struct track *track)
Christoph Lameter88a420e2007-05-06 14:49:45 -07004234{
4235 long start, end, pos;
4236 struct location *l;
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03004237 unsigned long caddr;
Christoph Lameter45edfa52007-05-09 02:32:45 -07004238 unsigned long age = jiffies - track->when;
Christoph Lameter88a420e2007-05-06 14:49:45 -07004239
4240 start = -1;
4241 end = t->count;
4242
4243 for ( ; ; ) {
4244 pos = start + (end - start + 1) / 2;
4245
4246 /*
4247 * There is nothing at "end". If we end up there
4248 * we need to add something to before end.
4249 */
4250 if (pos == end)
4251 break;
4252
4253 caddr = t->loc[pos].addr;
Christoph Lameter45edfa52007-05-09 02:32:45 -07004254 if (track->addr == caddr) {
4255
4256 l = &t->loc[pos];
4257 l->count++;
4258 if (track->when) {
4259 l->sum_time += age;
4260 if (age < l->min_time)
4261 l->min_time = age;
4262 if (age > l->max_time)
4263 l->max_time = age;
4264
4265 if (track->pid < l->min_pid)
4266 l->min_pid = track->pid;
4267 if (track->pid > l->max_pid)
4268 l->max_pid = track->pid;
4269
Rusty Russell174596a2009-01-01 10:12:29 +10304270 cpumask_set_cpu(track->cpu,
4271 to_cpumask(l->cpus));
Christoph Lameter45edfa52007-05-09 02:32:45 -07004272 }
4273 node_set(page_to_nid(virt_to_page(track)), l->nodes);
Christoph Lameter88a420e2007-05-06 14:49:45 -07004274 return 1;
4275 }
4276
Christoph Lameter45edfa52007-05-09 02:32:45 -07004277 if (track->addr < caddr)
Christoph Lameter88a420e2007-05-06 14:49:45 -07004278 end = pos;
4279 else
4280 start = pos;
4281 }
4282
4283 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07004284 * Not found. Insert new tracking element.
Christoph Lameter88a420e2007-05-06 14:49:45 -07004285 */
Christoph Lameter68dff6a2007-07-17 04:03:20 -07004286 if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC))
Christoph Lameter88a420e2007-05-06 14:49:45 -07004287 return 0;
4288
4289 l = t->loc + pos;
4290 if (pos < t->count)
4291 memmove(l + 1, l,
4292 (t->count - pos) * sizeof(struct location));
4293 t->count++;
4294 l->count = 1;
Christoph Lameter45edfa52007-05-09 02:32:45 -07004295 l->addr = track->addr;
4296 l->sum_time = age;
4297 l->min_time = age;
4298 l->max_time = age;
4299 l->min_pid = track->pid;
4300 l->max_pid = track->pid;
Rusty Russell174596a2009-01-01 10:12:29 +10304301 cpumask_clear(to_cpumask(l->cpus));
4302 cpumask_set_cpu(track->cpu, to_cpumask(l->cpus));
Christoph Lameter45edfa52007-05-09 02:32:45 -07004303 nodes_clear(l->nodes);
4304 node_set(page_to_nid(virt_to_page(track)), l->nodes);
Christoph Lameter88a420e2007-05-06 14:49:45 -07004305 return 1;
4306}
4307
4308static void process_slab(struct loc_track *t, struct kmem_cache *s,
Eric Dumazetbbd7d572010-03-24 22:25:47 +01004309 struct page *page, enum track_item alloc,
Namhyung Kima5dd5c12010-09-29 21:02:13 +09004310 unsigned long *map)
Christoph Lameter88a420e2007-05-06 14:49:45 -07004311{
Christoph Lametera973e9d2008-03-01 13:40:44 -08004312 void *addr = page_address(page);
Christoph Lameter88a420e2007-05-06 14:49:45 -07004313 void *p;
4314
Christoph Lameter39b26462008-04-14 19:11:30 +03004315 bitmap_zero(map, page->objects);
Christoph Lameter5f80b132011-04-15 14:48:13 -05004316 get_map(s, page, map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07004317
Christoph Lameter224a88b2008-04-14 19:11:31 +03004318 for_each_object(p, s, addr, page->objects)
Christoph Lameter45edfa52007-05-09 02:32:45 -07004319 if (!test_bit(slab_index(p, s, addr), map))
4320 add_location(t, s, get_track(s, p, alloc));
Christoph Lameter88a420e2007-05-06 14:49:45 -07004321}
4322
4323static int list_locations(struct kmem_cache *s, char *buf,
4324 enum track_item alloc)
4325{
Harvey Harrisone374d482008-01-31 15:20:50 -08004326 int len = 0;
Christoph Lameter88a420e2007-05-06 14:49:45 -07004327 unsigned long i;
Christoph Lameter68dff6a2007-07-17 04:03:20 -07004328 struct loc_track t = { 0, 0, NULL };
Christoph Lameter88a420e2007-05-06 14:49:45 -07004329 int node;
Eric Dumazetbbd7d572010-03-24 22:25:47 +01004330 unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
4331 sizeof(unsigned long), GFP_KERNEL);
Christoph Lameter88a420e2007-05-06 14:49:45 -07004332
Eric Dumazetbbd7d572010-03-24 22:25:47 +01004333 if (!map || !alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location),
4334 GFP_TEMPORARY)) {
4335 kfree(map);
Christoph Lameter68dff6a2007-07-17 04:03:20 -07004336 return sprintf(buf, "Out of memory\n");
Eric Dumazetbbd7d572010-03-24 22:25:47 +01004337 }
Christoph Lameter88a420e2007-05-06 14:49:45 -07004338 /* Push back cpu slabs */
4339 flush_all(s);
4340
Christoph Lameterf64dc582007-10-16 01:25:33 -07004341 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter88a420e2007-05-06 14:49:45 -07004342 struct kmem_cache_node *n = get_node(s, node);
4343 unsigned long flags;
4344 struct page *page;
4345
Christoph Lameter9e869432007-08-22 14:01:56 -07004346 if (!atomic_long_read(&n->nr_slabs))
Christoph Lameter88a420e2007-05-06 14:49:45 -07004347 continue;
4348
4349 spin_lock_irqsave(&n->list_lock, flags);
4350 list_for_each_entry(page, &n->partial, lru)
Eric Dumazetbbd7d572010-03-24 22:25:47 +01004351 process_slab(&t, s, page, alloc, map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07004352 list_for_each_entry(page, &n->full, lru)
Eric Dumazetbbd7d572010-03-24 22:25:47 +01004353 process_slab(&t, s, page, alloc, map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07004354 spin_unlock_irqrestore(&n->list_lock, flags);
4355 }
4356
4357 for (i = 0; i < t.count; i++) {
Christoph Lameter45edfa52007-05-09 02:32:45 -07004358 struct location *l = &t.loc[i];
Christoph Lameter88a420e2007-05-06 14:49:45 -07004359
Hugh Dickins9c246242008-12-09 13:14:27 -08004360 if (len > PAGE_SIZE - KSYM_SYMBOL_LEN - 100)
Christoph Lameter88a420e2007-05-06 14:49:45 -07004361 break;
Harvey Harrisone374d482008-01-31 15:20:50 -08004362 len += sprintf(buf + len, "%7ld ", l->count);
Christoph Lameter45edfa52007-05-09 02:32:45 -07004363
4364 if (l->addr)
Joe Perches62c70bc2011-01-13 15:45:52 -08004365 len += sprintf(buf + len, "%pS", (void *)l->addr);
Christoph Lameter88a420e2007-05-06 14:49:45 -07004366 else
Harvey Harrisone374d482008-01-31 15:20:50 -08004367 len += sprintf(buf + len, "<not-available>");
Christoph Lameter45edfa52007-05-09 02:32:45 -07004368
4369 if (l->sum_time != l->min_time) {
Harvey Harrisone374d482008-01-31 15:20:50 -08004370 len += sprintf(buf + len, " age=%ld/%ld/%ld",
Roman Zippelf8bd2252008-05-01 04:34:31 -07004371 l->min_time,
4372 (long)div_u64(l->sum_time, l->count),
4373 l->max_time);
Christoph Lameter45edfa52007-05-09 02:32:45 -07004374 } else
Harvey Harrisone374d482008-01-31 15:20:50 -08004375 len += sprintf(buf + len, " age=%ld",
Christoph Lameter45edfa52007-05-09 02:32:45 -07004376 l->min_time);
4377
4378 if (l->min_pid != l->max_pid)
Harvey Harrisone374d482008-01-31 15:20:50 -08004379 len += sprintf(buf + len, " pid=%ld-%ld",
Christoph Lameter45edfa52007-05-09 02:32:45 -07004380 l->min_pid, l->max_pid);
4381 else
Harvey Harrisone374d482008-01-31 15:20:50 -08004382 len += sprintf(buf + len, " pid=%ld",
Christoph Lameter45edfa52007-05-09 02:32:45 -07004383 l->min_pid);
4384
Rusty Russell174596a2009-01-01 10:12:29 +10304385 if (num_online_cpus() > 1 &&
4386 !cpumask_empty(to_cpumask(l->cpus)) &&
Harvey Harrisone374d482008-01-31 15:20:50 -08004387 len < PAGE_SIZE - 60) {
4388 len += sprintf(buf + len, " cpus=");
4389 len += cpulist_scnprintf(buf + len, PAGE_SIZE - len - 50,
Rusty Russell174596a2009-01-01 10:12:29 +10304390 to_cpumask(l->cpus));
Christoph Lameter45edfa52007-05-09 02:32:45 -07004391 }
4392
Christoph Lameter62bc62a2009-06-16 15:32:15 -07004393 if (nr_online_nodes > 1 && !nodes_empty(l->nodes) &&
Harvey Harrisone374d482008-01-31 15:20:50 -08004394 len < PAGE_SIZE - 60) {
4395 len += sprintf(buf + len, " nodes=");
4396 len += nodelist_scnprintf(buf + len, PAGE_SIZE - len - 50,
Christoph Lameter45edfa52007-05-09 02:32:45 -07004397 l->nodes);
4398 }
4399
Harvey Harrisone374d482008-01-31 15:20:50 -08004400 len += sprintf(buf + len, "\n");
Christoph Lameter88a420e2007-05-06 14:49:45 -07004401 }
4402
4403 free_loc_track(&t);
Eric Dumazetbbd7d572010-03-24 22:25:47 +01004404 kfree(map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07004405 if (!t.count)
Harvey Harrisone374d482008-01-31 15:20:50 -08004406 len += sprintf(buf, "No data\n");
4407 return len;
Christoph Lameter88a420e2007-05-06 14:49:45 -07004408}
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004409#endif
Christoph Lameter88a420e2007-05-06 14:49:45 -07004410
Christoph Lametera5a84752010-10-05 13:57:27 -05004411#ifdef SLUB_RESILIENCY_TEST
4412static void resiliency_test(void)
4413{
4414 u8 *p;
4415
4416 BUILD_BUG_ON(KMALLOC_MIN_SIZE > 16 || SLUB_PAGE_SHIFT < 10);
4417
4418 printk(KERN_ERR "SLUB resiliency testing\n");
4419 printk(KERN_ERR "-----------------------\n");
4420 printk(KERN_ERR "A. Corruption after allocation\n");
4421
4422 p = kzalloc(16, GFP_KERNEL);
4423 p[16] = 0x12;
4424 printk(KERN_ERR "\n1. kmalloc-16: Clobber Redzone/next pointer"
4425 " 0x12->0x%p\n\n", p + 16);
4426
4427 validate_slab_cache(kmalloc_caches[4]);
4428
4429 /* Hmmm... The next two are dangerous */
4430 p = kzalloc(32, GFP_KERNEL);
4431 p[32 + sizeof(void *)] = 0x34;
4432 printk(KERN_ERR "\n2. kmalloc-32: Clobber next pointer/next slab"
4433 " 0x34 -> -0x%p\n", p);
4434 printk(KERN_ERR
4435 "If allocated object is overwritten then not detectable\n\n");
4436
4437 validate_slab_cache(kmalloc_caches[5]);
4438 p = kzalloc(64, GFP_KERNEL);
4439 p += 64 + (get_cycles() & 0xff) * sizeof(void *);
4440 *p = 0x56;
4441 printk(KERN_ERR "\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n",
4442 p);
4443 printk(KERN_ERR
4444 "If allocated object is overwritten then not detectable\n\n");
4445 validate_slab_cache(kmalloc_caches[6]);
4446
4447 printk(KERN_ERR "\nB. Corruption after free\n");
4448 p = kzalloc(128, GFP_KERNEL);
4449 kfree(p);
4450 *p = 0x78;
4451 printk(KERN_ERR "1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p);
4452 validate_slab_cache(kmalloc_caches[7]);
4453
4454 p = kzalloc(256, GFP_KERNEL);
4455 kfree(p);
4456 p[50] = 0x9a;
4457 printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n",
4458 p);
4459 validate_slab_cache(kmalloc_caches[8]);
4460
4461 p = kzalloc(512, GFP_KERNEL);
4462 kfree(p);
4463 p[512] = 0xab;
4464 printk(KERN_ERR "\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p);
4465 validate_slab_cache(kmalloc_caches[9]);
4466}
4467#else
4468#ifdef CONFIG_SYSFS
4469static void resiliency_test(void) {};
4470#endif
4471#endif
4472
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004473#ifdef CONFIG_SYSFS
Christoph Lameter81819f02007-05-06 14:49:36 -07004474enum slab_stat_type {
Christoph Lameter205ab992008-04-14 19:11:40 +03004475 SL_ALL, /* All slabs */
4476 SL_PARTIAL, /* Only partially allocated slabs */
4477 SL_CPU, /* Only slabs used for cpu caches */
4478 SL_OBJECTS, /* Determine allocated objects not slabs */
4479 SL_TOTAL /* Determine object capacity not slabs */
Christoph Lameter81819f02007-05-06 14:49:36 -07004480};
4481
Christoph Lameter205ab992008-04-14 19:11:40 +03004482#define SO_ALL (1 << SL_ALL)
Christoph Lameter81819f02007-05-06 14:49:36 -07004483#define SO_PARTIAL (1 << SL_PARTIAL)
4484#define SO_CPU (1 << SL_CPU)
4485#define SO_OBJECTS (1 << SL_OBJECTS)
Christoph Lameter205ab992008-04-14 19:11:40 +03004486#define SO_TOTAL (1 << SL_TOTAL)
Christoph Lameter81819f02007-05-06 14:49:36 -07004487
Cyrill Gorcunov62e5c4b2008-03-02 23:28:24 +03004488static ssize_t show_slab_objects(struct kmem_cache *s,
4489 char *buf, unsigned long flags)
Christoph Lameter81819f02007-05-06 14:49:36 -07004490{
4491 unsigned long total = 0;
Christoph Lameter81819f02007-05-06 14:49:36 -07004492 int node;
4493 int x;
4494 unsigned long *nodes;
4495 unsigned long *per_cpu;
4496
4497 nodes = kzalloc(2 * sizeof(unsigned long) * nr_node_ids, GFP_KERNEL);
Cyrill Gorcunov62e5c4b2008-03-02 23:28:24 +03004498 if (!nodes)
4499 return -ENOMEM;
Christoph Lameter81819f02007-05-06 14:49:36 -07004500 per_cpu = nodes + nr_node_ids;
4501
Christoph Lameter205ab992008-04-14 19:11:40 +03004502 if (flags & SO_CPU) {
4503 int cpu;
Christoph Lameter81819f02007-05-06 14:49:36 -07004504
Christoph Lameter205ab992008-04-14 19:11:40 +03004505 for_each_possible_cpu(cpu) {
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06004506 struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
Christoph Lameter49e22582011-08-09 16:12:27 -05004507 struct page *page;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07004508
Christoph Lameter205ab992008-04-14 19:11:40 +03004509 if (!c || c->node < 0)
4510 continue;
4511
4512 if (c->page) {
4513 if (flags & SO_TOTAL)
4514 x = c->page->objects;
4515 else if (flags & SO_OBJECTS)
4516 x = c->page->inuse;
Christoph Lameter81819f02007-05-06 14:49:36 -07004517 else
4518 x = 1;
Christoph Lameter205ab992008-04-14 19:11:40 +03004519
Christoph Lameter81819f02007-05-06 14:49:36 -07004520 total += x;
Christoph Lameter205ab992008-04-14 19:11:40 +03004521 nodes[c->node] += x;
Christoph Lameter81819f02007-05-06 14:49:36 -07004522 }
Christoph Lameter49e22582011-08-09 16:12:27 -05004523 page = c->partial;
4524
4525 if (page) {
4526 x = page->pobjects;
4527 total += x;
4528 nodes[c->node] += x;
4529 }
Christoph Lameter205ab992008-04-14 19:11:40 +03004530 per_cpu[c->node]++;
Christoph Lameter81819f02007-05-06 14:49:36 -07004531 }
4532 }
4533
Christoph Lameter04d94872011-01-10 10:15:15 -06004534 lock_memory_hotplug();
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004535#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter205ab992008-04-14 19:11:40 +03004536 if (flags & SO_ALL) {
4537 for_each_node_state(node, N_NORMAL_MEMORY) {
4538 struct kmem_cache_node *n = get_node(s, node);
Christoph Lameter81819f02007-05-06 14:49:36 -07004539
Christoph Lameter205ab992008-04-14 19:11:40 +03004540 if (flags & SO_TOTAL)
4541 x = atomic_long_read(&n->total_objects);
4542 else if (flags & SO_OBJECTS)
4543 x = atomic_long_read(&n->total_objects) -
4544 count_partial(n, count_free);
4545
4546 else
4547 x = atomic_long_read(&n->nr_slabs);
4548 total += x;
4549 nodes[node] += x;
4550 }
4551
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004552 } else
4553#endif
4554 if (flags & SO_PARTIAL) {
Christoph Lameter205ab992008-04-14 19:11:40 +03004555 for_each_node_state(node, N_NORMAL_MEMORY) {
4556 struct kmem_cache_node *n = get_node(s, node);
4557
4558 if (flags & SO_TOTAL)
4559 x = count_partial(n, count_total);
4560 else if (flags & SO_OBJECTS)
4561 x = count_partial(n, count_inuse);
Christoph Lameter81819f02007-05-06 14:49:36 -07004562 else
4563 x = n->nr_partial;
4564 total += x;
4565 nodes[node] += x;
4566 }
Christoph Lameter81819f02007-05-06 14:49:36 -07004567 }
Christoph Lameter81819f02007-05-06 14:49:36 -07004568 x = sprintf(buf, "%lu", total);
4569#ifdef CONFIG_NUMA
Christoph Lameterf64dc582007-10-16 01:25:33 -07004570 for_each_node_state(node, N_NORMAL_MEMORY)
Christoph Lameter81819f02007-05-06 14:49:36 -07004571 if (nodes[node])
4572 x += sprintf(buf + x, " N%d=%lu",
4573 node, nodes[node]);
4574#endif
Christoph Lameter04d94872011-01-10 10:15:15 -06004575 unlock_memory_hotplug();
Christoph Lameter81819f02007-05-06 14:49:36 -07004576 kfree(nodes);
4577 return x + sprintf(buf + x, "\n");
4578}
4579
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004580#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter81819f02007-05-06 14:49:36 -07004581static int any_slab_objects(struct kmem_cache *s)
4582{
4583 int node;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07004584
4585 for_each_online_node(node) {
Christoph Lameter81819f02007-05-06 14:49:36 -07004586 struct kmem_cache_node *n = get_node(s, node);
4587
Christoph Lameterdfb4f092007-10-16 01:26:05 -07004588 if (!n)
4589 continue;
4590
Benjamin Herrenschmidt4ea33e22008-05-06 20:42:39 -07004591 if (atomic_long_read(&n->total_objects))
Christoph Lameter81819f02007-05-06 14:49:36 -07004592 return 1;
4593 }
4594 return 0;
4595}
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004596#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07004597
4598#define to_slab_attr(n) container_of(n, struct slab_attribute, attr)
Phil Carmody497888c2011-07-14 15:07:13 +03004599#define to_slab(n) container_of(n, struct kmem_cache, kobj)
Christoph Lameter81819f02007-05-06 14:49:36 -07004600
4601struct slab_attribute {
4602 struct attribute attr;
4603 ssize_t (*show)(struct kmem_cache *s, char *buf);
4604 ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count);
4605};
4606
4607#define SLAB_ATTR_RO(_name) \
4608 static struct slab_attribute _name##_attr = __ATTR_RO(_name)
4609
4610#define SLAB_ATTR(_name) \
4611 static struct slab_attribute _name##_attr = \
4612 __ATTR(_name, 0644, _name##_show, _name##_store)
4613
Christoph Lameter81819f02007-05-06 14:49:36 -07004614static ssize_t slab_size_show(struct kmem_cache *s, char *buf)
4615{
4616 return sprintf(buf, "%d\n", s->size);
4617}
4618SLAB_ATTR_RO(slab_size);
4619
4620static ssize_t align_show(struct kmem_cache *s, char *buf)
4621{
4622 return sprintf(buf, "%d\n", s->align);
4623}
4624SLAB_ATTR_RO(align);
4625
4626static ssize_t object_size_show(struct kmem_cache *s, char *buf)
4627{
4628 return sprintf(buf, "%d\n", s->objsize);
4629}
4630SLAB_ATTR_RO(object_size);
4631
4632static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf)
4633{
Christoph Lameter834f3d12008-04-14 19:11:31 +03004634 return sprintf(buf, "%d\n", oo_objects(s->oo));
Christoph Lameter81819f02007-05-06 14:49:36 -07004635}
4636SLAB_ATTR_RO(objs_per_slab);
4637
Christoph Lameter06b285d2008-04-14 19:11:41 +03004638static ssize_t order_store(struct kmem_cache *s,
4639 const char *buf, size_t length)
4640{
Christoph Lameter0121c6192008-04-29 16:11:12 -07004641 unsigned long order;
4642 int err;
4643
4644 err = strict_strtoul(buf, 10, &order);
4645 if (err)
4646 return err;
Christoph Lameter06b285d2008-04-14 19:11:41 +03004647
4648 if (order > slub_max_order || order < slub_min_order)
4649 return -EINVAL;
4650
4651 calculate_sizes(s, order);
4652 return length;
4653}
4654
Christoph Lameter81819f02007-05-06 14:49:36 -07004655static ssize_t order_show(struct kmem_cache *s, char *buf)
4656{
Christoph Lameter834f3d12008-04-14 19:11:31 +03004657 return sprintf(buf, "%d\n", oo_order(s->oo));
Christoph Lameter81819f02007-05-06 14:49:36 -07004658}
Christoph Lameter06b285d2008-04-14 19:11:41 +03004659SLAB_ATTR(order);
Christoph Lameter81819f02007-05-06 14:49:36 -07004660
David Rientjes73d342b2009-02-22 17:40:09 -08004661static ssize_t min_partial_show(struct kmem_cache *s, char *buf)
4662{
4663 return sprintf(buf, "%lu\n", s->min_partial);
4664}
4665
4666static ssize_t min_partial_store(struct kmem_cache *s, const char *buf,
4667 size_t length)
4668{
4669 unsigned long min;
4670 int err;
4671
4672 err = strict_strtoul(buf, 10, &min);
4673 if (err)
4674 return err;
4675
David Rientjesc0bdb232009-02-25 09:16:35 +02004676 set_min_partial(s, min);
David Rientjes73d342b2009-02-22 17:40:09 -08004677 return length;
4678}
4679SLAB_ATTR(min_partial);
4680
Christoph Lameter49e22582011-08-09 16:12:27 -05004681static ssize_t cpu_partial_show(struct kmem_cache *s, char *buf)
4682{
4683 return sprintf(buf, "%u\n", s->cpu_partial);
4684}
4685
4686static ssize_t cpu_partial_store(struct kmem_cache *s, const char *buf,
4687 size_t length)
4688{
4689 unsigned long objects;
4690 int err;
4691
4692 err = strict_strtoul(buf, 10, &objects);
4693 if (err)
4694 return err;
4695
4696 s->cpu_partial = objects;
4697 flush_all(s);
4698 return length;
4699}
4700SLAB_ATTR(cpu_partial);
4701
Christoph Lameter81819f02007-05-06 14:49:36 -07004702static ssize_t ctor_show(struct kmem_cache *s, char *buf)
4703{
Joe Perches62c70bc2011-01-13 15:45:52 -08004704 if (!s->ctor)
4705 return 0;
4706 return sprintf(buf, "%pS\n", s->ctor);
Christoph Lameter81819f02007-05-06 14:49:36 -07004707}
4708SLAB_ATTR_RO(ctor);
4709
Christoph Lameter81819f02007-05-06 14:49:36 -07004710static ssize_t aliases_show(struct kmem_cache *s, char *buf)
4711{
4712 return sprintf(buf, "%d\n", s->refcount - 1);
4713}
4714SLAB_ATTR_RO(aliases);
4715
Christoph Lameter81819f02007-05-06 14:49:36 -07004716static ssize_t partial_show(struct kmem_cache *s, char *buf)
4717{
Christoph Lameterd9acf4b2008-02-15 15:22:21 -08004718 return show_slab_objects(s, buf, SO_PARTIAL);
Christoph Lameter81819f02007-05-06 14:49:36 -07004719}
4720SLAB_ATTR_RO(partial);
4721
4722static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf)
4723{
Christoph Lameterd9acf4b2008-02-15 15:22:21 -08004724 return show_slab_objects(s, buf, SO_CPU);
Christoph Lameter81819f02007-05-06 14:49:36 -07004725}
4726SLAB_ATTR_RO(cpu_slabs);
4727
4728static ssize_t objects_show(struct kmem_cache *s, char *buf)
4729{
Christoph Lameter205ab992008-04-14 19:11:40 +03004730 return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS);
Christoph Lameter81819f02007-05-06 14:49:36 -07004731}
4732SLAB_ATTR_RO(objects);
4733
Christoph Lameter205ab992008-04-14 19:11:40 +03004734static ssize_t objects_partial_show(struct kmem_cache *s, char *buf)
4735{
4736 return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS);
4737}
4738SLAB_ATTR_RO(objects_partial);
4739
Christoph Lameter49e22582011-08-09 16:12:27 -05004740static ssize_t slabs_cpu_partial_show(struct kmem_cache *s, char *buf)
4741{
4742 int objects = 0;
4743 int pages = 0;
4744 int cpu;
4745 int len;
4746
4747 for_each_online_cpu(cpu) {
4748 struct page *page = per_cpu_ptr(s->cpu_slab, cpu)->partial;
4749
4750 if (page) {
4751 pages += page->pages;
4752 objects += page->pobjects;
4753 }
4754 }
4755
4756 len = sprintf(buf, "%d(%d)", objects, pages);
4757
4758#ifdef CONFIG_SMP
4759 for_each_online_cpu(cpu) {
4760 struct page *page = per_cpu_ptr(s->cpu_slab, cpu) ->partial;
4761
4762 if (page && len < PAGE_SIZE - 20)
4763 len += sprintf(buf + len, " C%d=%d(%d)", cpu,
4764 page->pobjects, page->pages);
4765 }
4766#endif
4767 return len + sprintf(buf + len, "\n");
4768}
4769SLAB_ATTR_RO(slabs_cpu_partial);
4770
Christoph Lameter81819f02007-05-06 14:49:36 -07004771static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf)
4772{
4773 return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT));
4774}
4775
4776static ssize_t reclaim_account_store(struct kmem_cache *s,
4777 const char *buf, size_t length)
4778{
4779 s->flags &= ~SLAB_RECLAIM_ACCOUNT;
4780 if (buf[0] == '1')
4781 s->flags |= SLAB_RECLAIM_ACCOUNT;
4782 return length;
4783}
4784SLAB_ATTR(reclaim_account);
4785
4786static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf)
4787{
Christoph Lameter5af60832007-05-06 14:49:56 -07004788 return sprintf(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN));
Christoph Lameter81819f02007-05-06 14:49:36 -07004789}
4790SLAB_ATTR_RO(hwcache_align);
4791
4792#ifdef CONFIG_ZONE_DMA
4793static ssize_t cache_dma_show(struct kmem_cache *s, char *buf)
4794{
4795 return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA));
4796}
4797SLAB_ATTR_RO(cache_dma);
4798#endif
4799
4800static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf)
4801{
4802 return sprintf(buf, "%d\n", !!(s->flags & SLAB_DESTROY_BY_RCU));
4803}
4804SLAB_ATTR_RO(destroy_by_rcu);
4805
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08004806static ssize_t reserved_show(struct kmem_cache *s, char *buf)
4807{
4808 return sprintf(buf, "%d\n", s->reserved);
4809}
4810SLAB_ATTR_RO(reserved);
4811
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004812#ifdef CONFIG_SLUB_DEBUG
Christoph Lametera5a84752010-10-05 13:57:27 -05004813static ssize_t slabs_show(struct kmem_cache *s, char *buf)
4814{
4815 return show_slab_objects(s, buf, SO_ALL);
4816}
4817SLAB_ATTR_RO(slabs);
4818
4819static ssize_t total_objects_show(struct kmem_cache *s, char *buf)
4820{
4821 return show_slab_objects(s, buf, SO_ALL|SO_TOTAL);
4822}
4823SLAB_ATTR_RO(total_objects);
4824
4825static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf)
4826{
4827 return sprintf(buf, "%d\n", !!(s->flags & SLAB_DEBUG_FREE));
4828}
4829
4830static ssize_t sanity_checks_store(struct kmem_cache *s,
4831 const char *buf, size_t length)
4832{
4833 s->flags &= ~SLAB_DEBUG_FREE;
Christoph Lameterb789ef52011-06-01 12:25:49 -05004834 if (buf[0] == '1') {
4835 s->flags &= ~__CMPXCHG_DOUBLE;
Christoph Lametera5a84752010-10-05 13:57:27 -05004836 s->flags |= SLAB_DEBUG_FREE;
Christoph Lameterb789ef52011-06-01 12:25:49 -05004837 }
Christoph Lametera5a84752010-10-05 13:57:27 -05004838 return length;
4839}
4840SLAB_ATTR(sanity_checks);
4841
4842static ssize_t trace_show(struct kmem_cache *s, char *buf)
4843{
4844 return sprintf(buf, "%d\n", !!(s->flags & SLAB_TRACE));
4845}
4846
4847static ssize_t trace_store(struct kmem_cache *s, const char *buf,
4848 size_t length)
4849{
4850 s->flags &= ~SLAB_TRACE;
Christoph Lameterb789ef52011-06-01 12:25:49 -05004851 if (buf[0] == '1') {
4852 s->flags &= ~__CMPXCHG_DOUBLE;
Christoph Lametera5a84752010-10-05 13:57:27 -05004853 s->flags |= SLAB_TRACE;
Christoph Lameterb789ef52011-06-01 12:25:49 -05004854 }
Christoph Lametera5a84752010-10-05 13:57:27 -05004855 return length;
4856}
4857SLAB_ATTR(trace);
4858
Christoph Lameter81819f02007-05-06 14:49:36 -07004859static ssize_t red_zone_show(struct kmem_cache *s, char *buf)
4860{
4861 return sprintf(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE));
4862}
4863
4864static ssize_t red_zone_store(struct kmem_cache *s,
4865 const char *buf, size_t length)
4866{
4867 if (any_slab_objects(s))
4868 return -EBUSY;
4869
4870 s->flags &= ~SLAB_RED_ZONE;
Christoph Lameterb789ef52011-06-01 12:25:49 -05004871 if (buf[0] == '1') {
4872 s->flags &= ~__CMPXCHG_DOUBLE;
Christoph Lameter81819f02007-05-06 14:49:36 -07004873 s->flags |= SLAB_RED_ZONE;
Christoph Lameterb789ef52011-06-01 12:25:49 -05004874 }
Christoph Lameter06b285d2008-04-14 19:11:41 +03004875 calculate_sizes(s, -1);
Christoph Lameter81819f02007-05-06 14:49:36 -07004876 return length;
4877}
4878SLAB_ATTR(red_zone);
4879
4880static ssize_t poison_show(struct kmem_cache *s, char *buf)
4881{
4882 return sprintf(buf, "%d\n", !!(s->flags & SLAB_POISON));
4883}
4884
4885static ssize_t poison_store(struct kmem_cache *s,
4886 const char *buf, size_t length)
4887{
4888 if (any_slab_objects(s))
4889 return -EBUSY;
4890
4891 s->flags &= ~SLAB_POISON;
Christoph Lameterb789ef52011-06-01 12:25:49 -05004892 if (buf[0] == '1') {
4893 s->flags &= ~__CMPXCHG_DOUBLE;
Christoph Lameter81819f02007-05-06 14:49:36 -07004894 s->flags |= SLAB_POISON;
Christoph Lameterb789ef52011-06-01 12:25:49 -05004895 }
Christoph Lameter06b285d2008-04-14 19:11:41 +03004896 calculate_sizes(s, -1);
Christoph Lameter81819f02007-05-06 14:49:36 -07004897 return length;
4898}
4899SLAB_ATTR(poison);
4900
4901static ssize_t store_user_show(struct kmem_cache *s, char *buf)
4902{
4903 return sprintf(buf, "%d\n", !!(s->flags & SLAB_STORE_USER));
4904}
4905
4906static ssize_t store_user_store(struct kmem_cache *s,
4907 const char *buf, size_t length)
4908{
4909 if (any_slab_objects(s))
4910 return -EBUSY;
4911
4912 s->flags &= ~SLAB_STORE_USER;
Christoph Lameterb789ef52011-06-01 12:25:49 -05004913 if (buf[0] == '1') {
4914 s->flags &= ~__CMPXCHG_DOUBLE;
Christoph Lameter81819f02007-05-06 14:49:36 -07004915 s->flags |= SLAB_STORE_USER;
Christoph Lameterb789ef52011-06-01 12:25:49 -05004916 }
Christoph Lameter06b285d2008-04-14 19:11:41 +03004917 calculate_sizes(s, -1);
Christoph Lameter81819f02007-05-06 14:49:36 -07004918 return length;
4919}
4920SLAB_ATTR(store_user);
4921
Christoph Lameter53e15af2007-05-06 14:49:43 -07004922static ssize_t validate_show(struct kmem_cache *s, char *buf)
4923{
4924 return 0;
4925}
4926
4927static ssize_t validate_store(struct kmem_cache *s,
4928 const char *buf, size_t length)
4929{
Christoph Lameter434e2452007-07-17 04:03:30 -07004930 int ret = -EINVAL;
4931
4932 if (buf[0] == '1') {
4933 ret = validate_slab_cache(s);
4934 if (ret >= 0)
4935 ret = length;
4936 }
4937 return ret;
Christoph Lameter53e15af2007-05-06 14:49:43 -07004938}
4939SLAB_ATTR(validate);
Christoph Lametera5a84752010-10-05 13:57:27 -05004940
4941static ssize_t alloc_calls_show(struct kmem_cache *s, char *buf)
4942{
4943 if (!(s->flags & SLAB_STORE_USER))
4944 return -ENOSYS;
4945 return list_locations(s, buf, TRACK_ALLOC);
4946}
4947SLAB_ATTR_RO(alloc_calls);
4948
4949static ssize_t free_calls_show(struct kmem_cache *s, char *buf)
4950{
4951 if (!(s->flags & SLAB_STORE_USER))
4952 return -ENOSYS;
4953 return list_locations(s, buf, TRACK_FREE);
4954}
4955SLAB_ATTR_RO(free_calls);
4956#endif /* CONFIG_SLUB_DEBUG */
4957
4958#ifdef CONFIG_FAILSLAB
4959static ssize_t failslab_show(struct kmem_cache *s, char *buf)
4960{
4961 return sprintf(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB));
4962}
4963
4964static ssize_t failslab_store(struct kmem_cache *s, const char *buf,
4965 size_t length)
4966{
4967 s->flags &= ~SLAB_FAILSLAB;
4968 if (buf[0] == '1')
4969 s->flags |= SLAB_FAILSLAB;
4970 return length;
4971}
4972SLAB_ATTR(failslab);
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05004973#endif
Christoph Lameter53e15af2007-05-06 14:49:43 -07004974
Christoph Lameter2086d262007-05-06 14:49:46 -07004975static ssize_t shrink_show(struct kmem_cache *s, char *buf)
4976{
4977 return 0;
4978}
4979
4980static ssize_t shrink_store(struct kmem_cache *s,
4981 const char *buf, size_t length)
4982{
4983 if (buf[0] == '1') {
4984 int rc = kmem_cache_shrink(s);
4985
4986 if (rc)
4987 return rc;
4988 } else
4989 return -EINVAL;
4990 return length;
4991}
4992SLAB_ATTR(shrink);
4993
Christoph Lameter81819f02007-05-06 14:49:36 -07004994#ifdef CONFIG_NUMA
Christoph Lameter98246012008-01-07 23:20:26 -08004995static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf)
Christoph Lameter81819f02007-05-06 14:49:36 -07004996{
Christoph Lameter98246012008-01-07 23:20:26 -08004997 return sprintf(buf, "%d\n", s->remote_node_defrag_ratio / 10);
Christoph Lameter81819f02007-05-06 14:49:36 -07004998}
4999
Christoph Lameter98246012008-01-07 23:20:26 -08005000static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s,
Christoph Lameter81819f02007-05-06 14:49:36 -07005001 const char *buf, size_t length)
5002{
Christoph Lameter0121c6192008-04-29 16:11:12 -07005003 unsigned long ratio;
5004 int err;
Christoph Lameter81819f02007-05-06 14:49:36 -07005005
Christoph Lameter0121c6192008-04-29 16:11:12 -07005006 err = strict_strtoul(buf, 10, &ratio);
5007 if (err)
5008 return err;
5009
Christoph Lametere2cb96b2008-08-19 08:51:22 -05005010 if (ratio <= 100)
Christoph Lameter0121c6192008-04-29 16:11:12 -07005011 s->remote_node_defrag_ratio = ratio * 10;
5012
Christoph Lameter81819f02007-05-06 14:49:36 -07005013 return length;
5014}
Christoph Lameter98246012008-01-07 23:20:26 -08005015SLAB_ATTR(remote_node_defrag_ratio);
Christoph Lameter81819f02007-05-06 14:49:36 -07005016#endif
5017
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005018#ifdef CONFIG_SLUB_STATS
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005019static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si)
5020{
5021 unsigned long sum = 0;
5022 int cpu;
5023 int len;
5024 int *data = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL);
5025
5026 if (!data)
5027 return -ENOMEM;
5028
5029 for_each_online_cpu(cpu) {
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06005030 unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si];
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005031
5032 data[cpu] = x;
5033 sum += x;
5034 }
5035
5036 len = sprintf(buf, "%lu", sum);
5037
Christoph Lameter50ef37b2008-04-14 18:52:05 +03005038#ifdef CONFIG_SMP
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005039 for_each_online_cpu(cpu) {
5040 if (data[cpu] && len < PAGE_SIZE - 20)
Christoph Lameter50ef37b2008-04-14 18:52:05 +03005041 len += sprintf(buf + len, " C%d=%u", cpu, data[cpu]);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005042 }
Christoph Lameter50ef37b2008-04-14 18:52:05 +03005043#endif
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005044 kfree(data);
5045 return len + sprintf(buf + len, "\n");
5046}
5047
David Rientjes78eb00c2009-10-15 02:20:22 -07005048static void clear_stat(struct kmem_cache *s, enum stat_item si)
5049{
5050 int cpu;
5051
5052 for_each_online_cpu(cpu)
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06005053 per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0;
David Rientjes78eb00c2009-10-15 02:20:22 -07005054}
5055
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005056#define STAT_ATTR(si, text) \
5057static ssize_t text##_show(struct kmem_cache *s, char *buf) \
5058{ \
5059 return show_stat(s, buf, si); \
5060} \
David Rientjes78eb00c2009-10-15 02:20:22 -07005061static ssize_t text##_store(struct kmem_cache *s, \
5062 const char *buf, size_t length) \
5063{ \
5064 if (buf[0] != '0') \
5065 return -EINVAL; \
5066 clear_stat(s, si); \
5067 return length; \
5068} \
5069SLAB_ATTR(text); \
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005070
5071STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath);
5072STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath);
5073STAT_ATTR(FREE_FASTPATH, free_fastpath);
5074STAT_ATTR(FREE_SLOWPATH, free_slowpath);
5075STAT_ATTR(FREE_FROZEN, free_frozen);
5076STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial);
5077STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial);
5078STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial);
5079STAT_ATTR(ALLOC_SLAB, alloc_slab);
5080STAT_ATTR(ALLOC_REFILL, alloc_refill);
Christoph Lametere36a2652011-06-01 12:25:57 -05005081STAT_ATTR(ALLOC_NODE_MISMATCH, alloc_node_mismatch);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005082STAT_ATTR(FREE_SLAB, free_slab);
5083STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush);
5084STAT_ATTR(DEACTIVATE_FULL, deactivate_full);
5085STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty);
5086STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head);
5087STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail);
5088STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees);
Christoph Lameter03e404a2011-06-01 12:25:58 -05005089STAT_ATTR(DEACTIVATE_BYPASS, deactivate_bypass);
Christoph Lameter65c33762008-04-14 19:11:40 +03005090STAT_ATTR(ORDER_FALLBACK, order_fallback);
Christoph Lameterb789ef52011-06-01 12:25:49 -05005091STAT_ATTR(CMPXCHG_DOUBLE_CPU_FAIL, cmpxchg_double_cpu_fail);
5092STAT_ATTR(CMPXCHG_DOUBLE_FAIL, cmpxchg_double_fail);
Christoph Lameter49e22582011-08-09 16:12:27 -05005093STAT_ATTR(CPU_PARTIAL_ALLOC, cpu_partial_alloc);
5094STAT_ATTR(CPU_PARTIAL_FREE, cpu_partial_free);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005095#endif
5096
Pekka Enberg06428782008-01-07 23:20:27 -08005097static struct attribute *slab_attrs[] = {
Christoph Lameter81819f02007-05-06 14:49:36 -07005098 &slab_size_attr.attr,
5099 &object_size_attr.attr,
5100 &objs_per_slab_attr.attr,
5101 &order_attr.attr,
David Rientjes73d342b2009-02-22 17:40:09 -08005102 &min_partial_attr.attr,
Christoph Lameter49e22582011-08-09 16:12:27 -05005103 &cpu_partial_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07005104 &objects_attr.attr,
Christoph Lameter205ab992008-04-14 19:11:40 +03005105 &objects_partial_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07005106 &partial_attr.attr,
5107 &cpu_slabs_attr.attr,
5108 &ctor_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07005109 &aliases_attr.attr,
5110 &align_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07005111 &hwcache_align_attr.attr,
5112 &reclaim_account_attr.attr,
5113 &destroy_by_rcu_attr.attr,
Christoph Lametera5a84752010-10-05 13:57:27 -05005114 &shrink_attr.attr,
Lai Jiangshanab9a0f12011-03-10 15:21:48 +08005115 &reserved_attr.attr,
Christoph Lameter49e22582011-08-09 16:12:27 -05005116 &slabs_cpu_partial_attr.attr,
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05005117#ifdef CONFIG_SLUB_DEBUG
Christoph Lametera5a84752010-10-05 13:57:27 -05005118 &total_objects_attr.attr,
5119 &slabs_attr.attr,
5120 &sanity_checks_attr.attr,
5121 &trace_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07005122 &red_zone_attr.attr,
5123 &poison_attr.attr,
5124 &store_user_attr.attr,
Christoph Lameter53e15af2007-05-06 14:49:43 -07005125 &validate_attr.attr,
Christoph Lameter88a420e2007-05-06 14:49:45 -07005126 &alloc_calls_attr.attr,
5127 &free_calls_attr.attr,
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05005128#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07005129#ifdef CONFIG_ZONE_DMA
5130 &cache_dma_attr.attr,
5131#endif
5132#ifdef CONFIG_NUMA
Christoph Lameter98246012008-01-07 23:20:26 -08005133 &remote_node_defrag_ratio_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07005134#endif
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005135#ifdef CONFIG_SLUB_STATS
5136 &alloc_fastpath_attr.attr,
5137 &alloc_slowpath_attr.attr,
5138 &free_fastpath_attr.attr,
5139 &free_slowpath_attr.attr,
5140 &free_frozen_attr.attr,
5141 &free_add_partial_attr.attr,
5142 &free_remove_partial_attr.attr,
5143 &alloc_from_partial_attr.attr,
5144 &alloc_slab_attr.attr,
5145 &alloc_refill_attr.attr,
Christoph Lametere36a2652011-06-01 12:25:57 -05005146 &alloc_node_mismatch_attr.attr,
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005147 &free_slab_attr.attr,
5148 &cpuslab_flush_attr.attr,
5149 &deactivate_full_attr.attr,
5150 &deactivate_empty_attr.attr,
5151 &deactivate_to_head_attr.attr,
5152 &deactivate_to_tail_attr.attr,
5153 &deactivate_remote_frees_attr.attr,
Christoph Lameter03e404a2011-06-01 12:25:58 -05005154 &deactivate_bypass_attr.attr,
Christoph Lameter65c33762008-04-14 19:11:40 +03005155 &order_fallback_attr.attr,
Christoph Lameterb789ef52011-06-01 12:25:49 -05005156 &cmpxchg_double_fail_attr.attr,
5157 &cmpxchg_double_cpu_fail_attr.attr,
Christoph Lameter49e22582011-08-09 16:12:27 -05005158 &cpu_partial_alloc_attr.attr,
5159 &cpu_partial_free_attr.attr,
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08005160#endif
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +03005161#ifdef CONFIG_FAILSLAB
5162 &failslab_attr.attr,
5163#endif
5164
Christoph Lameter81819f02007-05-06 14:49:36 -07005165 NULL
5166};
5167
5168static struct attribute_group slab_attr_group = {
5169 .attrs = slab_attrs,
5170};
5171
5172static ssize_t slab_attr_show(struct kobject *kobj,
5173 struct attribute *attr,
5174 char *buf)
5175{
5176 struct slab_attribute *attribute;
5177 struct kmem_cache *s;
5178 int err;
5179
5180 attribute = to_slab_attr(attr);
5181 s = to_slab(kobj);
5182
5183 if (!attribute->show)
5184 return -EIO;
5185
5186 err = attribute->show(s, buf);
5187
5188 return err;
5189}
5190
5191static ssize_t slab_attr_store(struct kobject *kobj,
5192 struct attribute *attr,
5193 const char *buf, size_t len)
5194{
5195 struct slab_attribute *attribute;
5196 struct kmem_cache *s;
5197 int err;
5198
5199 attribute = to_slab_attr(attr);
5200 s = to_slab(kobj);
5201
5202 if (!attribute->store)
5203 return -EIO;
5204
5205 err = attribute->store(s, buf, len);
5206
5207 return err;
5208}
5209
Christoph Lameter151c6022008-01-07 22:29:05 -08005210static void kmem_cache_release(struct kobject *kobj)
5211{
5212 struct kmem_cache *s = to_slab(kobj);
5213
Pekka Enberg84c1cf62010-09-14 23:21:12 +03005214 kfree(s->name);
Christoph Lameter151c6022008-01-07 22:29:05 -08005215 kfree(s);
5216}
5217
Emese Revfy52cf25d2010-01-19 02:58:23 +01005218static const struct sysfs_ops slab_sysfs_ops = {
Christoph Lameter81819f02007-05-06 14:49:36 -07005219 .show = slab_attr_show,
5220 .store = slab_attr_store,
5221};
5222
5223static struct kobj_type slab_ktype = {
5224 .sysfs_ops = &slab_sysfs_ops,
Christoph Lameter151c6022008-01-07 22:29:05 -08005225 .release = kmem_cache_release
Christoph Lameter81819f02007-05-06 14:49:36 -07005226};
5227
5228static int uevent_filter(struct kset *kset, struct kobject *kobj)
5229{
5230 struct kobj_type *ktype = get_ktype(kobj);
5231
5232 if (ktype == &slab_ktype)
5233 return 1;
5234 return 0;
5235}
5236
Emese Revfy9cd43612009-12-31 14:52:51 +01005237static const struct kset_uevent_ops slab_uevent_ops = {
Christoph Lameter81819f02007-05-06 14:49:36 -07005238 .filter = uevent_filter,
5239};
5240
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06005241static struct kset *slab_kset;
Christoph Lameter81819f02007-05-06 14:49:36 -07005242
5243#define ID_STR_LENGTH 64
5244
5245/* Create a unique string id for a slab cache:
Christoph Lameter6446faa2008-02-15 23:45:26 -08005246 *
5247 * Format :[flags-]size
Christoph Lameter81819f02007-05-06 14:49:36 -07005248 */
5249static char *create_unique_id(struct kmem_cache *s)
5250{
5251 char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL);
5252 char *p = name;
5253
5254 BUG_ON(!name);
5255
5256 *p++ = ':';
5257 /*
5258 * First flags affecting slabcache operations. We will only
5259 * get here for aliasable slabs so we do not need to support
5260 * too many flags. The flags here must cover all flags that
5261 * are matched during merging to guarantee that the id is
5262 * unique.
5263 */
5264 if (s->flags & SLAB_CACHE_DMA)
5265 *p++ = 'd';
5266 if (s->flags & SLAB_RECLAIM_ACCOUNT)
5267 *p++ = 'a';
5268 if (s->flags & SLAB_DEBUG_FREE)
5269 *p++ = 'F';
Vegard Nossum5a896d92008-04-04 00:54:48 +02005270 if (!(s->flags & SLAB_NOTRACK))
5271 *p++ = 't';
Christoph Lameter81819f02007-05-06 14:49:36 -07005272 if (p != name + 1)
5273 *p++ = '-';
5274 p += sprintf(p, "%07d", s->size);
5275 BUG_ON(p > name + ID_STR_LENGTH - 1);
5276 return name;
5277}
5278
5279static int sysfs_slab_add(struct kmem_cache *s)
5280{
5281 int err;
5282 const char *name;
5283 int unmergeable;
5284
5285 if (slab_state < SYSFS)
5286 /* Defer until later */
5287 return 0;
5288
5289 unmergeable = slab_unmergeable(s);
5290 if (unmergeable) {
5291 /*
5292 * Slabcache can never be merged so we can use the name proper.
5293 * This is typically the case for debug situations. In that
5294 * case we can catch duplicate names easily.
5295 */
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06005296 sysfs_remove_link(&slab_kset->kobj, s->name);
Christoph Lameter81819f02007-05-06 14:49:36 -07005297 name = s->name;
5298 } else {
5299 /*
5300 * Create a unique name for the slab as a target
5301 * for the symlinks.
5302 */
5303 name = create_unique_id(s);
5304 }
5305
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06005306 s->kobj.kset = slab_kset;
Greg Kroah-Hartman1eada112007-12-17 23:05:35 -07005307 err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, name);
5308 if (err) {
5309 kobject_put(&s->kobj);
Christoph Lameter81819f02007-05-06 14:49:36 -07005310 return err;
Greg Kroah-Hartman1eada112007-12-17 23:05:35 -07005311 }
Christoph Lameter81819f02007-05-06 14:49:36 -07005312
5313 err = sysfs_create_group(&s->kobj, &slab_attr_group);
Xiaotian Feng5788d8a2009-07-22 11:28:53 +08005314 if (err) {
5315 kobject_del(&s->kobj);
5316 kobject_put(&s->kobj);
Christoph Lameter81819f02007-05-06 14:49:36 -07005317 return err;
Xiaotian Feng5788d8a2009-07-22 11:28:53 +08005318 }
Christoph Lameter81819f02007-05-06 14:49:36 -07005319 kobject_uevent(&s->kobj, KOBJ_ADD);
5320 if (!unmergeable) {
5321 /* Setup first alias */
5322 sysfs_slab_alias(s, s->name);
5323 kfree(name);
5324 }
5325 return 0;
5326}
5327
5328static void sysfs_slab_remove(struct kmem_cache *s)
5329{
Christoph Lameter2bce6482010-07-19 11:39:11 -05005330 if (slab_state < SYSFS)
5331 /*
5332 * Sysfs has not been setup yet so no need to remove the
5333 * cache from sysfs.
5334 */
5335 return;
5336
Christoph Lameter81819f02007-05-06 14:49:36 -07005337 kobject_uevent(&s->kobj, KOBJ_REMOVE);
5338 kobject_del(&s->kobj);
Christoph Lameter151c6022008-01-07 22:29:05 -08005339 kobject_put(&s->kobj);
Christoph Lameter81819f02007-05-06 14:49:36 -07005340}
5341
5342/*
5343 * Need to buffer aliases during bootup until sysfs becomes
Nick Andrew9f6c708e2008-12-05 14:08:08 +11005344 * available lest we lose that information.
Christoph Lameter81819f02007-05-06 14:49:36 -07005345 */
5346struct saved_alias {
5347 struct kmem_cache *s;
5348 const char *name;
5349 struct saved_alias *next;
5350};
5351
Adrian Bunk5af328a2007-07-17 04:03:27 -07005352static struct saved_alias *alias_list;
Christoph Lameter81819f02007-05-06 14:49:36 -07005353
5354static int sysfs_slab_alias(struct kmem_cache *s, const char *name)
5355{
5356 struct saved_alias *al;
5357
5358 if (slab_state == SYSFS) {
5359 /*
5360 * If we have a leftover link then remove it.
5361 */
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06005362 sysfs_remove_link(&slab_kset->kobj, name);
5363 return sysfs_create_link(&slab_kset->kobj, &s->kobj, name);
Christoph Lameter81819f02007-05-06 14:49:36 -07005364 }
5365
5366 al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL);
5367 if (!al)
5368 return -ENOMEM;
5369
5370 al->s = s;
5371 al->name = name;
5372 al->next = alias_list;
5373 alias_list = al;
5374 return 0;
5375}
5376
5377static int __init slab_sysfs_init(void)
5378{
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07005379 struct kmem_cache *s;
Christoph Lameter81819f02007-05-06 14:49:36 -07005380 int err;
5381
Christoph Lameter2bce6482010-07-19 11:39:11 -05005382 down_write(&slub_lock);
5383
Greg Kroah-Hartman0ff21e42007-11-06 10:36:58 -08005384 slab_kset = kset_create_and_add("slab", &slab_uevent_ops, kernel_kobj);
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06005385 if (!slab_kset) {
Christoph Lameter2bce6482010-07-19 11:39:11 -05005386 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07005387 printk(KERN_ERR "Cannot register slab subsystem.\n");
5388 return -ENOSYS;
5389 }
5390
Christoph Lameter26a7bd02007-05-09 02:32:39 -07005391 slab_state = SYSFS;
5392
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07005393 list_for_each_entry(s, &slab_caches, list) {
Christoph Lameter26a7bd02007-05-09 02:32:39 -07005394 err = sysfs_slab_add(s);
Christoph Lameter5d540fb2007-08-30 23:56:26 -07005395 if (err)
5396 printk(KERN_ERR "SLUB: Unable to add boot slab %s"
5397 " to sysfs\n", s->name);
Christoph Lameter26a7bd02007-05-09 02:32:39 -07005398 }
Christoph Lameter81819f02007-05-06 14:49:36 -07005399
5400 while (alias_list) {
5401 struct saved_alias *al = alias_list;
5402
5403 alias_list = alias_list->next;
5404 err = sysfs_slab_alias(al->s, al->name);
Christoph Lameter5d540fb2007-08-30 23:56:26 -07005405 if (err)
5406 printk(KERN_ERR "SLUB: Unable to add boot slab alias"
5407 " %s to sysfs\n", s->name);
Christoph Lameter81819f02007-05-06 14:49:36 -07005408 kfree(al);
5409 }
5410
Christoph Lameter2bce6482010-07-19 11:39:11 -05005411 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07005412 resiliency_test();
5413 return 0;
5414}
5415
5416__initcall(slab_sysfs_init);
Christoph Lameterab4d5ed2010-10-05 13:57:26 -05005417#endif /* CONFIG_SYSFS */
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01005418
5419/*
5420 * The /proc/slabinfo ABI
5421 */
Linus Torvalds158a9622008-01-02 13:04:48 -08005422#ifdef CONFIG_SLABINFO
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01005423static void print_slabinfo_header(struct seq_file *m)
5424{
5425 seq_puts(m, "slabinfo - version: 2.1\n");
5426 seq_puts(m, "# name <active_objs> <num_objs> <objsize> "
5427 "<objperslab> <pagesperslab>");
5428 seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
5429 seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
5430 seq_putc(m, '\n');
5431}
5432
5433static void *s_start(struct seq_file *m, loff_t *pos)
5434{
5435 loff_t n = *pos;
5436
5437 down_read(&slub_lock);
5438 if (!n)
5439 print_slabinfo_header(m);
5440
5441 return seq_list_start(&slab_caches, *pos);
5442}
5443
5444static void *s_next(struct seq_file *m, void *p, loff_t *pos)
5445{
5446 return seq_list_next(p, &slab_caches, pos);
5447}
5448
5449static void s_stop(struct seq_file *m, void *p)
5450{
5451 up_read(&slub_lock);
5452}
5453
5454static int s_show(struct seq_file *m, void *p)
5455{
5456 unsigned long nr_partials = 0;
5457 unsigned long nr_slabs = 0;
5458 unsigned long nr_inuse = 0;
Christoph Lameter205ab992008-04-14 19:11:40 +03005459 unsigned long nr_objs = 0;
5460 unsigned long nr_free = 0;
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01005461 struct kmem_cache *s;
5462 int node;
5463
5464 s = list_entry(p, struct kmem_cache, list);
5465
5466 for_each_online_node(node) {
5467 struct kmem_cache_node *n = get_node(s, node);
5468
5469 if (!n)
5470 continue;
5471
5472 nr_partials += n->nr_partial;
5473 nr_slabs += atomic_long_read(&n->nr_slabs);
Christoph Lameter205ab992008-04-14 19:11:40 +03005474 nr_objs += atomic_long_read(&n->total_objects);
5475 nr_free += count_partial(n, count_free);
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01005476 }
5477
Christoph Lameter205ab992008-04-14 19:11:40 +03005478 nr_inuse = nr_objs - nr_free;
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01005479
5480 seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", s->name, nr_inuse,
Christoph Lameter834f3d12008-04-14 19:11:31 +03005481 nr_objs, s->size, oo_objects(s->oo),
5482 (1 << oo_order(s->oo)));
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01005483 seq_printf(m, " : tunables %4u %4u %4u", 0, 0, 0);
5484 seq_printf(m, " : slabdata %6lu %6lu %6lu", nr_slabs, nr_slabs,
5485 0UL);
5486 seq_putc(m, '\n');
5487 return 0;
5488}
5489
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +04005490static const struct seq_operations slabinfo_op = {
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01005491 .start = s_start,
5492 .next = s_next,
5493 .stop = s_stop,
5494 .show = s_show,
5495};
5496
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +04005497static int slabinfo_open(struct inode *inode, struct file *file)
5498{
5499 return seq_open(file, &slabinfo_op);
5500}
5501
5502static const struct file_operations proc_slabinfo_operations = {
5503 .open = slabinfo_open,
5504 .read = seq_read,
5505 .llseek = seq_lseek,
5506 .release = seq_release,
5507};
5508
5509static int __init slab_proc_init(void)
5510{
WANG Congcf5d1132009-08-18 19:11:40 +03005511 proc_create("slabinfo", S_IRUGO, NULL, &proc_slabinfo_operations);
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +04005512 return 0;
5513}
5514module_init(slab_proc_init);
Linus Torvalds158a9622008-01-02 13:04:48 -08005515#endif /* CONFIG_SLABINFO */