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Christoph Lameter81819f02007-05-06 14:49:36 -07001/*
2 * SLUB: A slab allocator that limits cache line use instead of queuing
3 * objects in per cpu and per node lists.
4 *
5 * The allocator synchronizes using per slab locks and only
6 * uses a centralized lock to manage a pool of partial slabs.
7 *
Christoph Lametercde53532008-07-04 09:59:22 -07008 * (C) 2007 SGI, Christoph Lameter
Christoph Lameter81819f02007-05-06 14:49:36 -07009 */
10
11#include <linux/mm.h>
Nick Piggin1eb5ac62009-05-05 19:13:44 +100012#include <linux/swap.h> /* struct reclaim_state */
Christoph Lameter81819f02007-05-06 14:49:36 -070013#include <linux/module.h>
14#include <linux/bit_spinlock.h>
15#include <linux/interrupt.h>
16#include <linux/bitops.h>
17#include <linux/slab.h>
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +040018#include <linux/proc_fs.h>
Christoph Lameter81819f02007-05-06 14:49:36 -070019#include <linux/seq_file.h>
Zhaolei02af61b2009-04-10 14:26:18 +080020#include <linux/kmemtrace.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>
Christoph Lameter81819f02007-05-06 14:49:36 -070031
32/*
33 * Lock order:
34 * 1. slab_lock(page)
35 * 2. slab->list_lock
36 *
37 * The slab_lock protects operations on the object of a particular
38 * slab and its metadata in the page struct. If the slab lock
39 * has been taken then no allocations nor frees can be performed
40 * on the objects in the slab nor can the slab be added or removed
41 * from the partial or full lists since this would mean modifying
42 * the page_struct of the slab.
43 *
44 * The list_lock protects the partial and full list on each node and
45 * the partial slab counter. If taken then no new slabs may be added or
46 * removed from the lists nor make the number of partial slabs be modified.
47 * (Note that the total number of slabs is an atomic value that may be
48 * modified without taking the list lock).
49 *
50 * The list_lock is a centralized lock and thus we avoid taking it as
51 * much as possible. As long as SLUB does not have to handle partial
52 * slabs, operations can continue without any centralized lock. F.e.
53 * allocating a long series of objects that fill up slabs does not require
54 * the list lock.
55 *
56 * The lock order is sometimes inverted when we are trying to get a slab
57 * off a list. We take the list_lock and then look for a page on the list
58 * to use. While we do that objects in the slabs may be freed. We can
59 * only operate on the slab if we have also taken the slab_lock. So we use
60 * a slab_trylock() on the slab. If trylock was successful then no frees
61 * can occur anymore and we can use the slab for allocations etc. If the
62 * slab_trylock() does not succeed then frees are in progress in the slab and
63 * we must stay away from it for a while since we may cause a bouncing
64 * cacheline if we try to acquire the lock. So go onto the next slab.
65 * If all pages are busy then we may allocate a new slab instead of reusing
66 * a partial slab. A new slab has noone operating on it and thus there is
67 * no danger of cacheline contention.
68 *
69 * Interrupts are disabled during allocation and deallocation in order to
70 * make the slab allocator safe to use in the context of an irq. In addition
71 * interrupts are disabled to ensure that the processor does not change
72 * while handling per_cpu slabs, due to kernel preemption.
73 *
74 * SLUB assigns one slab for allocation to each processor.
75 * Allocations only occur from these slabs called cpu slabs.
76 *
Christoph Lameter672bba32007-05-09 02:32:39 -070077 * Slabs with free elements are kept on a partial list and during regular
78 * operations no list for full slabs is used. If an object in a full slab is
Christoph Lameter81819f02007-05-06 14:49:36 -070079 * freed then the slab will show up again on the partial lists.
Christoph Lameter672bba32007-05-09 02:32:39 -070080 * We track full slabs for debugging purposes though because otherwise we
81 * cannot scan all objects.
Christoph Lameter81819f02007-05-06 14:49:36 -070082 *
83 * Slabs are freed when they become empty. Teardown and setup is
84 * minimal so we rely on the page allocators per cpu caches for
85 * fast frees and allocs.
86 *
87 * Overloading of page flags that are otherwise used for LRU management.
88 *
Christoph Lameter4b6f0752007-05-16 22:10:53 -070089 * PageActive The slab is frozen and exempt from list processing.
90 * This means that the slab is dedicated to a purpose
91 * such as satisfying allocations for a specific
92 * processor. Objects may be freed in the slab while
93 * it is frozen but slab_free will then skip the usual
94 * list operations. It is up to the processor holding
95 * the slab to integrate the slab into the slab lists
96 * when the slab is no longer needed.
97 *
98 * One use of this flag is to mark slabs that are
99 * used for allocations. Then such a slab becomes a cpu
100 * slab. The cpu slab may be equipped with an additional
Christoph Lameterdfb4f092007-10-16 01:26:05 -0700101 * freelist that allows lockless access to
Christoph Lameter894b8782007-05-10 03:15:16 -0700102 * free objects in addition to the regular freelist
103 * that requires the slab lock.
Christoph Lameter81819f02007-05-06 14:49:36 -0700104 *
105 * PageError Slab requires special handling due to debug
106 * options set. This moves slab handling out of
Christoph Lameter894b8782007-05-10 03:15:16 -0700107 * the fast path and disables lockless freelists.
Christoph Lameter81819f02007-05-06 14:49:36 -0700108 */
109
Christoph Lameter5577bd82007-05-16 22:10:56 -0700110#ifdef CONFIG_SLUB_DEBUG
Andy Whitcroft8a380822008-07-23 21:27:18 -0700111#define SLABDEBUG 1
Christoph Lameter5577bd82007-05-16 22:10:56 -0700112#else
113#define SLABDEBUG 0
114#endif
115
Christoph Lameter81819f02007-05-06 14:49:36 -0700116/*
117 * Issues still to be resolved:
118 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700119 * - Support PAGE_ALLOC_DEBUG. Should be easy to do.
120 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700121 * - Variable sizing of the per node arrays
122 */
123
124/* Enable to test recovery from slab corruption on boot */
125#undef SLUB_RESILIENCY_TEST
126
Christoph Lameter81819f02007-05-06 14:49:36 -0700127/*
Christoph Lameter2086d262007-05-06 14:49:46 -0700128 * Mininum number of partial slabs. These will be left on the partial
129 * lists even if they are empty. kmem_cache_shrink may reclaim them.
130 */
Christoph Lameter76be8952007-12-21 14:37:37 -0800131#define MIN_PARTIAL 5
Christoph Lametere95eed52007-05-06 14:49:44 -0700132
Christoph Lameter2086d262007-05-06 14:49:46 -0700133/*
134 * Maximum number of desirable partial slabs.
135 * The existence of more partial slabs makes kmem_cache_shrink
136 * sort the partial list by the number of objects in the.
137 */
138#define MAX_PARTIAL 10
139
Christoph Lameter81819f02007-05-06 14:49:36 -0700140#define DEBUG_DEFAULT_FLAGS (SLAB_DEBUG_FREE | SLAB_RED_ZONE | \
141 SLAB_POISON | SLAB_STORE_USER)
Christoph Lameter672bba32007-05-09 02:32:39 -0700142
Christoph Lameter81819f02007-05-06 14:49:36 -0700143/*
David Rientjes3de47212009-07-27 18:30:35 -0700144 * Debugging flags that require metadata to be stored in the slab. These get
145 * disabled when slub_debug=O is used and a cache's min order increases with
146 * metadata.
David Rientjesfa5ec8a2009-07-07 00:14:14 -0700147 */
David Rientjes3de47212009-07-27 18:30:35 -0700148#define DEBUG_METADATA_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
David Rientjesfa5ec8a2009-07-07 00:14:14 -0700149
150/*
Christoph Lameter81819f02007-05-06 14:49:36 -0700151 * Set of flags that will prevent slab merging
152 */
153#define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +0300154 SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \
155 SLAB_FAILSLAB)
Christoph Lameter81819f02007-05-06 14:49:36 -0700156
157#define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \
Vegard Nossum5a896d92008-04-04 00:54:48 +0200158 SLAB_CACHE_DMA | SLAB_NOTRACK)
Christoph Lameter81819f02007-05-06 14:49:36 -0700159
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400160#define OO_SHIFT 16
161#define OO_MASK ((1 << OO_SHIFT) - 1)
162#define MAX_OBJS_PER_PAGE 65535 /* since page.objects is u16 */
163
Christoph Lameter81819f02007-05-06 14:49:36 -0700164/* Internal SLUB flags */
Christoph Lameter1ceef402007-08-07 15:11:48 -0700165#define __OBJECT_POISON 0x80000000 /* Poison object */
166#define __SYSFS_ADD_DEFERRED 0x40000000 /* Not yet visible via sysfs */
Christoph Lameter81819f02007-05-06 14:49:36 -0700167
168static int kmem_size = sizeof(struct kmem_cache);
169
170#ifdef CONFIG_SMP
171static struct notifier_block slab_notifier;
172#endif
173
174static enum {
175 DOWN, /* No slab functionality available */
176 PARTIAL, /* kmem_cache_open() works but kmalloc does not */
Christoph Lameter672bba32007-05-09 02:32:39 -0700177 UP, /* Everything works but does not show up in sysfs */
Christoph Lameter81819f02007-05-06 14:49:36 -0700178 SYSFS /* Sysfs up */
179} slab_state = DOWN;
180
181/* A list of all slab caches on the system */
182static DECLARE_RWSEM(slub_lock);
Adrian Bunk5af328a2007-07-17 04:03:27 -0700183static LIST_HEAD(slab_caches);
Christoph Lameter81819f02007-05-06 14:49:36 -0700184
Christoph Lameter02cbc872007-05-09 02:32:43 -0700185/*
186 * Tracking user of a slab.
187 */
188struct track {
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300189 unsigned long addr; /* Called from address */
Christoph Lameter02cbc872007-05-09 02:32:43 -0700190 int cpu; /* Was running on cpu */
191 int pid; /* Pid context */
192 unsigned long when; /* When did the operation occur */
193};
194
195enum track_item { TRACK_ALLOC, TRACK_FREE };
196
Christoph Lameterf6acb632008-04-29 16:16:06 -0700197#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter81819f02007-05-06 14:49:36 -0700198static int sysfs_slab_add(struct kmem_cache *);
199static int sysfs_slab_alias(struct kmem_cache *, const char *);
200static void sysfs_slab_remove(struct kmem_cache *);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800201
Christoph Lameter81819f02007-05-06 14:49:36 -0700202#else
Christoph Lameter0c710012007-07-17 04:03:24 -0700203static inline int sysfs_slab_add(struct kmem_cache *s) { return 0; }
204static inline int sysfs_slab_alias(struct kmem_cache *s, const char *p)
205 { return 0; }
Christoph Lameter151c6022008-01-07 22:29:05 -0800206static inline void sysfs_slab_remove(struct kmem_cache *s)
207{
208 kfree(s);
209}
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800210
Christoph Lameter81819f02007-05-06 14:49:36 -0700211#endif
212
Christoph Lameter84e554e62009-12-18 16:26:23 -0600213static inline void stat(struct kmem_cache *s, enum stat_item si)
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800214{
215#ifdef CONFIG_SLUB_STATS
Christoph Lameter84e554e62009-12-18 16:26:23 -0600216 __this_cpu_inc(s->cpu_slab->stat[si]);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -0800217#endif
218}
219
Christoph Lameter81819f02007-05-06 14:49:36 -0700220/********************************************************************
221 * Core slab cache functions
222 *******************************************************************/
223
224int slab_is_available(void)
225{
226 return slab_state >= UP;
227}
228
229static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
230{
231#ifdef CONFIG_NUMA
232 return s->node[node];
233#else
234 return &s->local_node;
235#endif
236}
237
Christoph Lameter6446faa2008-02-15 23:45:26 -0800238/* Verify that a pointer has an address that is valid within a slab page */
Christoph Lameter02cbc872007-05-09 02:32:43 -0700239static inline int check_valid_pointer(struct kmem_cache *s,
240 struct page *page, const void *object)
241{
242 void *base;
243
Christoph Lametera973e9d2008-03-01 13:40:44 -0800244 if (!object)
Christoph Lameter02cbc872007-05-09 02:32:43 -0700245 return 1;
246
Christoph Lametera973e9d2008-03-01 13:40:44 -0800247 base = page_address(page);
Christoph Lameter39b26462008-04-14 19:11:30 +0300248 if (object < base || object >= base + page->objects * s->size ||
Christoph Lameter02cbc872007-05-09 02:32:43 -0700249 (object - base) % s->size) {
250 return 0;
251 }
252
253 return 1;
254}
255
Christoph Lameter7656c722007-05-09 02:32:40 -0700256static inline void *get_freepointer(struct kmem_cache *s, void *object)
257{
258 return *(void **)(object + s->offset);
259}
260
261static inline void set_freepointer(struct kmem_cache *s, void *object, void *fp)
262{
263 *(void **)(object + s->offset) = fp;
264}
265
266/* Loop over all objects in a slab */
Christoph Lameter224a88b2008-04-14 19:11:31 +0300267#define for_each_object(__p, __s, __addr, __objects) \
268 for (__p = (__addr); __p < (__addr) + (__objects) * (__s)->size;\
Christoph Lameter7656c722007-05-09 02:32:40 -0700269 __p += (__s)->size)
270
271/* Scan freelist */
272#define for_each_free_object(__p, __s, __free) \
Christoph Lametera973e9d2008-03-01 13:40:44 -0800273 for (__p = (__free); __p; __p = get_freepointer((__s), __p))
Christoph Lameter7656c722007-05-09 02:32:40 -0700274
275/* Determine object index from a given position */
276static inline int slab_index(void *p, struct kmem_cache *s, void *addr)
277{
278 return (p - addr) / s->size;
279}
280
Christoph Lameter834f3d12008-04-14 19:11:31 +0300281static inline struct kmem_cache_order_objects oo_make(int order,
282 unsigned long size)
283{
284 struct kmem_cache_order_objects x = {
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400285 (order << OO_SHIFT) + (PAGE_SIZE << order) / size
Christoph Lameter834f3d12008-04-14 19:11:31 +0300286 };
287
288 return x;
289}
290
291static inline int oo_order(struct kmem_cache_order_objects x)
292{
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400293 return x.x >> OO_SHIFT;
Christoph Lameter834f3d12008-04-14 19:11:31 +0300294}
295
296static inline int oo_objects(struct kmem_cache_order_objects x)
297{
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400298 return x.x & OO_MASK;
Christoph Lameter834f3d12008-04-14 19:11:31 +0300299}
300
Christoph Lameter41ecc552007-05-09 02:32:44 -0700301#ifdef CONFIG_SLUB_DEBUG
302/*
303 * Debug settings:
304 */
Christoph Lameterf0630ff2007-07-15 23:38:14 -0700305#ifdef CONFIG_SLUB_DEBUG_ON
306static int slub_debug = DEBUG_DEFAULT_FLAGS;
307#else
Christoph Lameter41ecc552007-05-09 02:32:44 -0700308static int slub_debug;
Christoph Lameterf0630ff2007-07-15 23:38:14 -0700309#endif
Christoph Lameter41ecc552007-05-09 02:32:44 -0700310
311static char *slub_debug_slabs;
David Rientjesfa5ec8a2009-07-07 00:14:14 -0700312static int disable_higher_order_debug;
Christoph Lameter41ecc552007-05-09 02:32:44 -0700313
Christoph Lameter7656c722007-05-09 02:32:40 -0700314/*
Christoph Lameter81819f02007-05-06 14:49:36 -0700315 * Object debugging
316 */
317static void print_section(char *text, u8 *addr, unsigned int length)
318{
319 int i, offset;
320 int newline = 1;
321 char ascii[17];
322
323 ascii[16] = 0;
324
325 for (i = 0; i < length; i++) {
326 if (newline) {
Christoph Lameter24922682007-07-17 04:03:18 -0700327 printk(KERN_ERR "%8s 0x%p: ", text, addr + i);
Christoph Lameter81819f02007-05-06 14:49:36 -0700328 newline = 0;
329 }
Pekka Enberg06428782008-01-07 23:20:27 -0800330 printk(KERN_CONT " %02x", addr[i]);
Christoph Lameter81819f02007-05-06 14:49:36 -0700331 offset = i % 16;
332 ascii[offset] = isgraph(addr[i]) ? addr[i] : '.';
333 if (offset == 15) {
Pekka Enberg06428782008-01-07 23:20:27 -0800334 printk(KERN_CONT " %s\n", ascii);
Christoph Lameter81819f02007-05-06 14:49:36 -0700335 newline = 1;
336 }
337 }
338 if (!newline) {
339 i %= 16;
340 while (i < 16) {
Pekka Enberg06428782008-01-07 23:20:27 -0800341 printk(KERN_CONT " ");
Christoph Lameter81819f02007-05-06 14:49:36 -0700342 ascii[i] = ' ';
343 i++;
344 }
Pekka Enberg06428782008-01-07 23:20:27 -0800345 printk(KERN_CONT " %s\n", ascii);
Christoph Lameter81819f02007-05-06 14:49:36 -0700346 }
347}
348
Christoph Lameter81819f02007-05-06 14:49:36 -0700349static struct track *get_track(struct kmem_cache *s, void *object,
350 enum track_item alloc)
351{
352 struct track *p;
353
354 if (s->offset)
355 p = object + s->offset + sizeof(void *);
356 else
357 p = object + s->inuse;
358
359 return p + alloc;
360}
361
362static void set_track(struct kmem_cache *s, void *object,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300363 enum track_item alloc, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -0700364{
Akinobu Mita1a00df42009-03-07 00:36:21 +0900365 struct track *p = get_track(s, object, alloc);
Christoph Lameter81819f02007-05-06 14:49:36 -0700366
Christoph Lameter81819f02007-05-06 14:49:36 -0700367 if (addr) {
368 p->addr = addr;
369 p->cpu = smp_processor_id();
Alexey Dobriyan88e4ccf2008-06-23 02:58:37 +0400370 p->pid = current->pid;
Christoph Lameter81819f02007-05-06 14:49:36 -0700371 p->when = jiffies;
372 } else
373 memset(p, 0, sizeof(struct track));
374}
375
Christoph Lameter81819f02007-05-06 14:49:36 -0700376static void init_tracking(struct kmem_cache *s, void *object)
377{
Christoph Lameter24922682007-07-17 04:03:18 -0700378 if (!(s->flags & SLAB_STORE_USER))
379 return;
380
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300381 set_track(s, object, TRACK_FREE, 0UL);
382 set_track(s, object, TRACK_ALLOC, 0UL);
Christoph Lameter81819f02007-05-06 14:49:36 -0700383}
384
385static void print_track(const char *s, struct track *t)
386{
387 if (!t->addr)
388 return;
389
Linus Torvalds7daf7052008-07-14 12:12:53 -0700390 printk(KERN_ERR "INFO: %s in %pS age=%lu cpu=%u pid=%d\n",
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300391 s, (void *)t->addr, jiffies - t->when, t->cpu, t->pid);
Christoph Lameter81819f02007-05-06 14:49:36 -0700392}
393
Christoph Lameter24922682007-07-17 04:03:18 -0700394static void print_tracking(struct kmem_cache *s, void *object)
395{
396 if (!(s->flags & SLAB_STORE_USER))
397 return;
398
399 print_track("Allocated", get_track(s, object, TRACK_ALLOC));
400 print_track("Freed", get_track(s, object, TRACK_FREE));
401}
402
403static void print_page_info(struct page *page)
404{
Christoph Lameter39b26462008-04-14 19:11:30 +0300405 printk(KERN_ERR "INFO: Slab 0x%p objects=%u used=%u fp=0x%p flags=0x%04lx\n",
406 page, page->objects, page->inuse, page->freelist, page->flags);
Christoph Lameter24922682007-07-17 04:03:18 -0700407
408}
409
410static void slab_bug(struct kmem_cache *s, char *fmt, ...)
411{
412 va_list args;
413 char buf[100];
414
415 va_start(args, fmt);
416 vsnprintf(buf, sizeof(buf), fmt, args);
417 va_end(args);
418 printk(KERN_ERR "========================================"
419 "=====================================\n");
420 printk(KERN_ERR "BUG %s: %s\n", s->name, buf);
421 printk(KERN_ERR "----------------------------------------"
422 "-------------------------------------\n\n");
423}
424
425static void slab_fix(struct kmem_cache *s, char *fmt, ...)
426{
427 va_list args;
428 char buf[100];
429
430 va_start(args, fmt);
431 vsnprintf(buf, sizeof(buf), fmt, args);
432 va_end(args);
433 printk(KERN_ERR "FIX %s: %s\n", s->name, buf);
434}
435
436static void print_trailer(struct kmem_cache *s, struct page *page, u8 *p)
Christoph Lameter81819f02007-05-06 14:49:36 -0700437{
438 unsigned int off; /* Offset of last byte */
Christoph Lametera973e9d2008-03-01 13:40:44 -0800439 u8 *addr = page_address(page);
Christoph Lameter24922682007-07-17 04:03:18 -0700440
441 print_tracking(s, p);
442
443 print_page_info(page);
444
445 printk(KERN_ERR "INFO: Object 0x%p @offset=%tu fp=0x%p\n\n",
446 p, p - addr, get_freepointer(s, p));
447
448 if (p > addr + 16)
449 print_section("Bytes b4", p - 16, 16);
450
Pekka Enberg0ebd6522008-07-19 14:17:22 +0300451 print_section("Object", p, min_t(unsigned long, s->objsize, PAGE_SIZE));
Christoph Lameter81819f02007-05-06 14:49:36 -0700452
453 if (s->flags & SLAB_RED_ZONE)
454 print_section("Redzone", p + s->objsize,
455 s->inuse - s->objsize);
456
Christoph Lameter81819f02007-05-06 14:49:36 -0700457 if (s->offset)
458 off = s->offset + sizeof(void *);
459 else
460 off = s->inuse;
461
Christoph Lameter24922682007-07-17 04:03:18 -0700462 if (s->flags & SLAB_STORE_USER)
Christoph Lameter81819f02007-05-06 14:49:36 -0700463 off += 2 * sizeof(struct track);
Christoph Lameter81819f02007-05-06 14:49:36 -0700464
465 if (off != s->size)
466 /* Beginning of the filler is the free pointer */
Christoph Lameter24922682007-07-17 04:03:18 -0700467 print_section("Padding", p + off, s->size - off);
468
469 dump_stack();
Christoph Lameter81819f02007-05-06 14:49:36 -0700470}
471
472static void object_err(struct kmem_cache *s, struct page *page,
473 u8 *object, char *reason)
474{
Christoph Lameter3dc50632008-04-23 12:28:01 -0700475 slab_bug(s, "%s", reason);
Christoph Lameter24922682007-07-17 04:03:18 -0700476 print_trailer(s, page, object);
Christoph Lameter81819f02007-05-06 14:49:36 -0700477}
478
Christoph Lameter24922682007-07-17 04:03:18 -0700479static void slab_err(struct kmem_cache *s, struct page *page, char *fmt, ...)
Christoph Lameter81819f02007-05-06 14:49:36 -0700480{
481 va_list args;
482 char buf[100];
483
Christoph Lameter24922682007-07-17 04:03:18 -0700484 va_start(args, fmt);
485 vsnprintf(buf, sizeof(buf), fmt, args);
Christoph Lameter81819f02007-05-06 14:49:36 -0700486 va_end(args);
Christoph Lameter3dc50632008-04-23 12:28:01 -0700487 slab_bug(s, "%s", buf);
Christoph Lameter24922682007-07-17 04:03:18 -0700488 print_page_info(page);
Christoph Lameter81819f02007-05-06 14:49:36 -0700489 dump_stack();
490}
491
492static void init_object(struct kmem_cache *s, void *object, int active)
493{
494 u8 *p = object;
495
496 if (s->flags & __OBJECT_POISON) {
497 memset(p, POISON_FREE, s->objsize - 1);
Pekka Enberg06428782008-01-07 23:20:27 -0800498 p[s->objsize - 1] = POISON_END;
Christoph Lameter81819f02007-05-06 14:49:36 -0700499 }
500
501 if (s->flags & SLAB_RED_ZONE)
502 memset(p + s->objsize,
503 active ? SLUB_RED_ACTIVE : SLUB_RED_INACTIVE,
504 s->inuse - s->objsize);
505}
506
Christoph Lameter24922682007-07-17 04:03:18 -0700507static u8 *check_bytes(u8 *start, unsigned int value, unsigned int bytes)
Christoph Lameter81819f02007-05-06 14:49:36 -0700508{
509 while (bytes) {
510 if (*start != (u8)value)
Christoph Lameter24922682007-07-17 04:03:18 -0700511 return start;
Christoph Lameter81819f02007-05-06 14:49:36 -0700512 start++;
513 bytes--;
514 }
Christoph Lameter24922682007-07-17 04:03:18 -0700515 return NULL;
516}
517
518static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
519 void *from, void *to)
520{
521 slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data);
522 memset(from, data, to - from);
523}
524
525static int check_bytes_and_report(struct kmem_cache *s, struct page *page,
526 u8 *object, char *what,
Pekka Enberg06428782008-01-07 23:20:27 -0800527 u8 *start, unsigned int value, unsigned int bytes)
Christoph Lameter24922682007-07-17 04:03:18 -0700528{
529 u8 *fault;
530 u8 *end;
531
532 fault = check_bytes(start, value, bytes);
533 if (!fault)
534 return 1;
535
536 end = start + bytes;
537 while (end > fault && end[-1] == value)
538 end--;
539
540 slab_bug(s, "%s overwritten", what);
541 printk(KERN_ERR "INFO: 0x%p-0x%p. First byte 0x%x instead of 0x%x\n",
542 fault, end - 1, fault[0], value);
543 print_trailer(s, page, object);
544
545 restore_bytes(s, what, value, fault, end);
546 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700547}
548
Christoph Lameter81819f02007-05-06 14:49:36 -0700549/*
550 * Object layout:
551 *
552 * object address
553 * Bytes of the object to be managed.
554 * If the freepointer may overlay the object then the free
555 * pointer is the first word of the object.
Christoph Lameter672bba32007-05-09 02:32:39 -0700556 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700557 * Poisoning uses 0x6b (POISON_FREE) and the last byte is
558 * 0xa5 (POISON_END)
559 *
560 * object + s->objsize
561 * Padding to reach word boundary. This is also used for Redzoning.
Christoph Lameter672bba32007-05-09 02:32:39 -0700562 * Padding is extended by another word if Redzoning is enabled and
563 * objsize == inuse.
564 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700565 * We fill with 0xbb (RED_INACTIVE) for inactive objects and with
566 * 0xcc (RED_ACTIVE) for objects in use.
567 *
568 * object + s->inuse
Christoph Lameter672bba32007-05-09 02:32:39 -0700569 * Meta data starts here.
570 *
Christoph Lameter81819f02007-05-06 14:49:36 -0700571 * A. Free pointer (if we cannot overwrite object on free)
572 * B. Tracking data for SLAB_STORE_USER
Christoph Lameter672bba32007-05-09 02:32:39 -0700573 * C. Padding to reach required alignment boundary or at mininum
Christoph Lameter6446faa2008-02-15 23:45:26 -0800574 * one word if debugging is on to be able to detect writes
Christoph Lameter672bba32007-05-09 02:32:39 -0700575 * before the word boundary.
576 *
577 * Padding is done using 0x5a (POISON_INUSE)
Christoph Lameter81819f02007-05-06 14:49:36 -0700578 *
579 * object + s->size
Christoph Lameter672bba32007-05-09 02:32:39 -0700580 * Nothing is used beyond s->size.
Christoph Lameter81819f02007-05-06 14:49:36 -0700581 *
Christoph Lameter672bba32007-05-09 02:32:39 -0700582 * If slabcaches are merged then the objsize and inuse boundaries are mostly
583 * ignored. And therefore no slab options that rely on these boundaries
Christoph Lameter81819f02007-05-06 14:49:36 -0700584 * may be used with merged slabcaches.
585 */
586
Christoph Lameter81819f02007-05-06 14:49:36 -0700587static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p)
588{
589 unsigned long off = s->inuse; /* The end of info */
590
591 if (s->offset)
592 /* Freepointer is placed after the object. */
593 off += sizeof(void *);
594
595 if (s->flags & SLAB_STORE_USER)
596 /* We also have user information there */
597 off += 2 * sizeof(struct track);
598
599 if (s->size == off)
600 return 1;
601
Christoph Lameter24922682007-07-17 04:03:18 -0700602 return check_bytes_and_report(s, page, p, "Object padding",
603 p + off, POISON_INUSE, s->size - off);
Christoph Lameter81819f02007-05-06 14:49:36 -0700604}
605
Christoph Lameter39b26462008-04-14 19:11:30 +0300606/* Check the pad bytes at the end of a slab page */
Christoph Lameter81819f02007-05-06 14:49:36 -0700607static int slab_pad_check(struct kmem_cache *s, struct page *page)
608{
Christoph Lameter24922682007-07-17 04:03:18 -0700609 u8 *start;
610 u8 *fault;
611 u8 *end;
612 int length;
613 int remainder;
Christoph Lameter81819f02007-05-06 14:49:36 -0700614
615 if (!(s->flags & SLAB_POISON))
616 return 1;
617
Christoph Lametera973e9d2008-03-01 13:40:44 -0800618 start = page_address(page);
Christoph Lameter834f3d12008-04-14 19:11:31 +0300619 length = (PAGE_SIZE << compound_order(page));
Christoph Lameter39b26462008-04-14 19:11:30 +0300620 end = start + length;
621 remainder = length % s->size;
Christoph Lameter81819f02007-05-06 14:49:36 -0700622 if (!remainder)
623 return 1;
624
Christoph Lameter39b26462008-04-14 19:11:30 +0300625 fault = check_bytes(end - remainder, POISON_INUSE, remainder);
Christoph Lameter24922682007-07-17 04:03:18 -0700626 if (!fault)
627 return 1;
628 while (end > fault && end[-1] == POISON_INUSE)
629 end--;
630
631 slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1);
Christoph Lameter39b26462008-04-14 19:11:30 +0300632 print_section("Padding", end - remainder, remainder);
Christoph Lameter24922682007-07-17 04:03:18 -0700633
Eric Dumazet8a3d2712009-09-03 16:08:06 +0200634 restore_bytes(s, "slab padding", POISON_INUSE, end - remainder, end);
Christoph Lameter24922682007-07-17 04:03:18 -0700635 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700636}
637
638static int check_object(struct kmem_cache *s, struct page *page,
639 void *object, int active)
640{
641 u8 *p = object;
642 u8 *endobject = object + s->objsize;
643
644 if (s->flags & SLAB_RED_ZONE) {
645 unsigned int red =
646 active ? SLUB_RED_ACTIVE : SLUB_RED_INACTIVE;
647
Christoph Lameter24922682007-07-17 04:03:18 -0700648 if (!check_bytes_and_report(s, page, object, "Redzone",
649 endobject, red, s->inuse - s->objsize))
Christoph Lameter81819f02007-05-06 14:49:36 -0700650 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700651 } else {
Ingo Molnar3adbefe2008-02-05 17:57:39 -0800652 if ((s->flags & SLAB_POISON) && s->objsize < s->inuse) {
653 check_bytes_and_report(s, page, p, "Alignment padding",
654 endobject, POISON_INUSE, s->inuse - s->objsize);
655 }
Christoph Lameter81819f02007-05-06 14:49:36 -0700656 }
657
658 if (s->flags & SLAB_POISON) {
659 if (!active && (s->flags & __OBJECT_POISON) &&
Christoph Lameter24922682007-07-17 04:03:18 -0700660 (!check_bytes_and_report(s, page, p, "Poison", p,
661 POISON_FREE, s->objsize - 1) ||
662 !check_bytes_and_report(s, page, p, "Poison",
Pekka Enberg06428782008-01-07 23:20:27 -0800663 p + s->objsize - 1, POISON_END, 1)))
Christoph Lameter81819f02007-05-06 14:49:36 -0700664 return 0;
Christoph Lameter81819f02007-05-06 14:49:36 -0700665 /*
666 * check_pad_bytes cleans up on its own.
667 */
668 check_pad_bytes(s, page, p);
669 }
670
671 if (!s->offset && active)
672 /*
673 * Object and freepointer overlap. Cannot check
674 * freepointer while object is allocated.
675 */
676 return 1;
677
678 /* Check free pointer validity */
679 if (!check_valid_pointer(s, page, get_freepointer(s, p))) {
680 object_err(s, page, p, "Freepointer corrupt");
681 /*
Nick Andrew9f6c708e2008-12-05 14:08:08 +1100682 * No choice but to zap it and thus lose the remainder
Christoph Lameter81819f02007-05-06 14:49:36 -0700683 * of the free objects in this slab. May cause
Christoph Lameter672bba32007-05-09 02:32:39 -0700684 * another error because the object count is now wrong.
Christoph Lameter81819f02007-05-06 14:49:36 -0700685 */
Christoph Lametera973e9d2008-03-01 13:40:44 -0800686 set_freepointer(s, p, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -0700687 return 0;
688 }
689 return 1;
690}
691
692static int check_slab(struct kmem_cache *s, struct page *page)
693{
Christoph Lameter39b26462008-04-14 19:11:30 +0300694 int maxobj;
695
Christoph Lameter81819f02007-05-06 14:49:36 -0700696 VM_BUG_ON(!irqs_disabled());
697
698 if (!PageSlab(page)) {
Christoph Lameter24922682007-07-17 04:03:18 -0700699 slab_err(s, page, "Not a valid slab page");
Christoph Lameter81819f02007-05-06 14:49:36 -0700700 return 0;
701 }
Christoph Lameter39b26462008-04-14 19:11:30 +0300702
703 maxobj = (PAGE_SIZE << compound_order(page)) / s->size;
704 if (page->objects > maxobj) {
705 slab_err(s, page, "objects %u > max %u",
706 s->name, page->objects, maxobj);
707 return 0;
708 }
709 if (page->inuse > page->objects) {
Christoph Lameter24922682007-07-17 04:03:18 -0700710 slab_err(s, page, "inuse %u > max %u",
Christoph Lameter39b26462008-04-14 19:11:30 +0300711 s->name, page->inuse, page->objects);
Christoph Lameter81819f02007-05-06 14:49:36 -0700712 return 0;
713 }
714 /* Slab_pad_check fixes things up after itself */
715 slab_pad_check(s, page);
716 return 1;
717}
718
719/*
Christoph Lameter672bba32007-05-09 02:32:39 -0700720 * Determine if a certain object on a page is on the freelist. Must hold the
721 * slab lock to guarantee that the chains are in a consistent state.
Christoph Lameter81819f02007-05-06 14:49:36 -0700722 */
723static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
724{
725 int nr = 0;
726 void *fp = page->freelist;
727 void *object = NULL;
Christoph Lameter224a88b2008-04-14 19:11:31 +0300728 unsigned long max_objects;
Christoph Lameter81819f02007-05-06 14:49:36 -0700729
Christoph Lameter39b26462008-04-14 19:11:30 +0300730 while (fp && nr <= page->objects) {
Christoph Lameter81819f02007-05-06 14:49:36 -0700731 if (fp == search)
732 return 1;
733 if (!check_valid_pointer(s, page, fp)) {
734 if (object) {
735 object_err(s, page, object,
736 "Freechain corrupt");
Christoph Lametera973e9d2008-03-01 13:40:44 -0800737 set_freepointer(s, object, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -0700738 break;
739 } else {
Christoph Lameter24922682007-07-17 04:03:18 -0700740 slab_err(s, page, "Freepointer corrupt");
Christoph Lametera973e9d2008-03-01 13:40:44 -0800741 page->freelist = NULL;
Christoph Lameter39b26462008-04-14 19:11:30 +0300742 page->inuse = page->objects;
Christoph Lameter24922682007-07-17 04:03:18 -0700743 slab_fix(s, "Freelist cleared");
Christoph Lameter81819f02007-05-06 14:49:36 -0700744 return 0;
745 }
746 break;
747 }
748 object = fp;
749 fp = get_freepointer(s, object);
750 nr++;
751 }
752
Christoph Lameter224a88b2008-04-14 19:11:31 +0300753 max_objects = (PAGE_SIZE << compound_order(page)) / s->size;
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +0400754 if (max_objects > MAX_OBJS_PER_PAGE)
755 max_objects = MAX_OBJS_PER_PAGE;
Christoph Lameter224a88b2008-04-14 19:11:31 +0300756
757 if (page->objects != max_objects) {
758 slab_err(s, page, "Wrong number of objects. Found %d but "
759 "should be %d", page->objects, max_objects);
760 page->objects = max_objects;
761 slab_fix(s, "Number of objects adjusted.");
762 }
Christoph Lameter39b26462008-04-14 19:11:30 +0300763 if (page->inuse != page->objects - nr) {
Christoph Lameter70d71222007-05-06 14:49:47 -0700764 slab_err(s, page, "Wrong object count. Counter is %d but "
Christoph Lameter39b26462008-04-14 19:11:30 +0300765 "counted were %d", page->inuse, page->objects - nr);
766 page->inuse = page->objects - nr;
Christoph Lameter24922682007-07-17 04:03:18 -0700767 slab_fix(s, "Object count adjusted.");
Christoph Lameter81819f02007-05-06 14:49:36 -0700768 }
769 return search == NULL;
770}
771
Christoph Lameter0121c6192008-04-29 16:11:12 -0700772static void trace(struct kmem_cache *s, struct page *page, void *object,
773 int alloc)
Christoph Lameter3ec09742007-05-16 22:11:00 -0700774{
775 if (s->flags & SLAB_TRACE) {
776 printk(KERN_INFO "TRACE %s %s 0x%p inuse=%d fp=0x%p\n",
777 s->name,
778 alloc ? "alloc" : "free",
779 object, page->inuse,
780 page->freelist);
781
782 if (!alloc)
783 print_section("Object", (void *)object, s->objsize);
784
785 dump_stack();
786 }
787}
788
Christoph Lameter643b1132007-05-06 14:49:42 -0700789/*
Christoph Lameter672bba32007-05-09 02:32:39 -0700790 * Tracking of fully allocated slabs for debugging purposes.
Christoph Lameter643b1132007-05-06 14:49:42 -0700791 */
Christoph Lametere95eed52007-05-06 14:49:44 -0700792static void add_full(struct kmem_cache_node *n, struct page *page)
Christoph Lameter643b1132007-05-06 14:49:42 -0700793{
Christoph Lameter643b1132007-05-06 14:49:42 -0700794 spin_lock(&n->list_lock);
795 list_add(&page->lru, &n->full);
796 spin_unlock(&n->list_lock);
797}
798
799static void remove_full(struct kmem_cache *s, struct page *page)
800{
801 struct kmem_cache_node *n;
802
803 if (!(s->flags & SLAB_STORE_USER))
804 return;
805
806 n = get_node(s, page_to_nid(page));
807
808 spin_lock(&n->list_lock);
809 list_del(&page->lru);
810 spin_unlock(&n->list_lock);
811}
812
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300813/* Tracking of the number of slabs for debugging purposes */
814static inline unsigned long slabs_node(struct kmem_cache *s, int node)
815{
816 struct kmem_cache_node *n = get_node(s, node);
817
818 return atomic_long_read(&n->nr_slabs);
819}
820
Alexander Beregalov26c02cf2009-06-11 14:08:48 +0400821static inline unsigned long node_nr_slabs(struct kmem_cache_node *n)
822{
823 return atomic_long_read(&n->nr_slabs);
824}
825
Christoph Lameter205ab992008-04-14 19:11:40 +0300826static inline void inc_slabs_node(struct kmem_cache *s, int node, int objects)
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300827{
828 struct kmem_cache_node *n = get_node(s, node);
829
830 /*
831 * May be called early in order to allocate a slab for the
832 * kmem_cache_node structure. Solve the chicken-egg
833 * dilemma by deferring the increment of the count during
834 * bootstrap (see early_kmem_cache_node_alloc).
835 */
Christoph Lameter205ab992008-04-14 19:11:40 +0300836 if (!NUMA_BUILD || n) {
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300837 atomic_long_inc(&n->nr_slabs);
Christoph Lameter205ab992008-04-14 19:11:40 +0300838 atomic_long_add(objects, &n->total_objects);
839 }
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300840}
Christoph Lameter205ab992008-04-14 19:11:40 +0300841static inline void dec_slabs_node(struct kmem_cache *s, int node, int objects)
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300842{
843 struct kmem_cache_node *n = get_node(s, node);
844
845 atomic_long_dec(&n->nr_slabs);
Christoph Lameter205ab992008-04-14 19:11:40 +0300846 atomic_long_sub(objects, &n->total_objects);
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300847}
848
849/* Object debug checks for alloc/free paths */
Christoph Lameter3ec09742007-05-16 22:11:00 -0700850static void setup_object_debug(struct kmem_cache *s, struct page *page,
851 void *object)
852{
853 if (!(s->flags & (SLAB_STORE_USER|SLAB_RED_ZONE|__OBJECT_POISON)))
854 return;
855
856 init_object(s, object, 0);
857 init_tracking(s, object);
858}
859
860static int alloc_debug_processing(struct kmem_cache *s, struct page *page,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300861 void *object, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -0700862{
863 if (!check_slab(s, page))
864 goto bad;
865
Christoph Lameterd692ef62008-02-15 23:45:24 -0800866 if (!on_freelist(s, page, object)) {
Christoph Lameter24922682007-07-17 04:03:18 -0700867 object_err(s, page, object, "Object already allocated");
Christoph Lameter70d71222007-05-06 14:49:47 -0700868 goto bad;
Christoph Lameter81819f02007-05-06 14:49:36 -0700869 }
870
871 if (!check_valid_pointer(s, page, object)) {
872 object_err(s, page, object, "Freelist Pointer check fails");
Christoph Lameter70d71222007-05-06 14:49:47 -0700873 goto bad;
Christoph Lameter81819f02007-05-06 14:49:36 -0700874 }
875
Christoph Lameterd692ef62008-02-15 23:45:24 -0800876 if (!check_object(s, page, object, 0))
Christoph Lameter81819f02007-05-06 14:49:36 -0700877 goto bad;
Christoph Lameter81819f02007-05-06 14:49:36 -0700878
Christoph Lameter3ec09742007-05-16 22:11:00 -0700879 /* Success perform special debug activities for allocs */
880 if (s->flags & SLAB_STORE_USER)
881 set_track(s, object, TRACK_ALLOC, addr);
882 trace(s, page, object, 1);
883 init_object(s, object, 1);
Christoph Lameter81819f02007-05-06 14:49:36 -0700884 return 1;
Christoph Lameter3ec09742007-05-16 22:11:00 -0700885
Christoph Lameter81819f02007-05-06 14:49:36 -0700886bad:
887 if (PageSlab(page)) {
888 /*
889 * If this is a slab page then lets do the best we can
890 * to avoid issues in the future. Marking all objects
Christoph Lameter672bba32007-05-09 02:32:39 -0700891 * as used avoids touching the remaining objects.
Christoph Lameter81819f02007-05-06 14:49:36 -0700892 */
Christoph Lameter24922682007-07-17 04:03:18 -0700893 slab_fix(s, "Marking all objects used");
Christoph Lameter39b26462008-04-14 19:11:30 +0300894 page->inuse = page->objects;
Christoph Lametera973e9d2008-03-01 13:40:44 -0800895 page->freelist = NULL;
Christoph Lameter81819f02007-05-06 14:49:36 -0700896 }
897 return 0;
898}
899
Christoph Lameter3ec09742007-05-16 22:11:00 -0700900static int free_debug_processing(struct kmem_cache *s, struct page *page,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +0300901 void *object, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -0700902{
903 if (!check_slab(s, page))
904 goto fail;
905
906 if (!check_valid_pointer(s, page, object)) {
Christoph Lameter70d71222007-05-06 14:49:47 -0700907 slab_err(s, page, "Invalid object pointer 0x%p", object);
Christoph Lameter81819f02007-05-06 14:49:36 -0700908 goto fail;
909 }
910
911 if (on_freelist(s, page, object)) {
Christoph Lameter24922682007-07-17 04:03:18 -0700912 object_err(s, page, object, "Object already free");
Christoph Lameter81819f02007-05-06 14:49:36 -0700913 goto fail;
914 }
915
916 if (!check_object(s, page, object, 1))
917 return 0;
918
919 if (unlikely(s != page->slab)) {
Ingo Molnar3adbefe2008-02-05 17:57:39 -0800920 if (!PageSlab(page)) {
Christoph Lameter70d71222007-05-06 14:49:47 -0700921 slab_err(s, page, "Attempt to free object(0x%p) "
922 "outside of slab", object);
Ingo Molnar3adbefe2008-02-05 17:57:39 -0800923 } else if (!page->slab) {
Christoph Lameter81819f02007-05-06 14:49:36 -0700924 printk(KERN_ERR
Christoph Lameter70d71222007-05-06 14:49:47 -0700925 "SLUB <none>: no slab for object 0x%p.\n",
Christoph Lameter81819f02007-05-06 14:49:36 -0700926 object);
Christoph Lameter70d71222007-05-06 14:49:47 -0700927 dump_stack();
Pekka Enberg06428782008-01-07 23:20:27 -0800928 } else
Christoph Lameter24922682007-07-17 04:03:18 -0700929 object_err(s, page, object,
930 "page slab pointer corrupt.");
Christoph Lameter81819f02007-05-06 14:49:36 -0700931 goto fail;
932 }
Christoph Lameter3ec09742007-05-16 22:11:00 -0700933
934 /* Special debug activities for freeing objects */
Andy Whitcroft8a380822008-07-23 21:27:18 -0700935 if (!PageSlubFrozen(page) && !page->freelist)
Christoph Lameter3ec09742007-05-16 22:11:00 -0700936 remove_full(s, page);
937 if (s->flags & SLAB_STORE_USER)
938 set_track(s, object, TRACK_FREE, addr);
939 trace(s, page, object, 0);
940 init_object(s, object, 0);
Christoph Lameter81819f02007-05-06 14:49:36 -0700941 return 1;
Christoph Lameter3ec09742007-05-16 22:11:00 -0700942
Christoph Lameter81819f02007-05-06 14:49:36 -0700943fail:
Christoph Lameter24922682007-07-17 04:03:18 -0700944 slab_fix(s, "Object at 0x%p not freed", object);
Christoph Lameter81819f02007-05-06 14:49:36 -0700945 return 0;
946}
947
Christoph Lameter41ecc552007-05-09 02:32:44 -0700948static int __init setup_slub_debug(char *str)
949{
Christoph Lameterf0630ff2007-07-15 23:38:14 -0700950 slub_debug = DEBUG_DEFAULT_FLAGS;
951 if (*str++ != '=' || !*str)
952 /*
953 * No options specified. Switch on full debugging.
954 */
955 goto out;
Christoph Lameter41ecc552007-05-09 02:32:44 -0700956
957 if (*str == ',')
Christoph Lameterf0630ff2007-07-15 23:38:14 -0700958 /*
959 * No options but restriction on slabs. This means full
960 * debugging for slabs matching a pattern.
961 */
962 goto check_slabs;
963
David Rientjesfa5ec8a2009-07-07 00:14:14 -0700964 if (tolower(*str) == 'o') {
965 /*
966 * Avoid enabling debugging on caches if its minimum order
967 * would increase as a result.
968 */
969 disable_higher_order_debug = 1;
970 goto out;
971 }
972
Christoph Lameterf0630ff2007-07-15 23:38:14 -0700973 slub_debug = 0;
974 if (*str == '-')
975 /*
976 * Switch off all debugging measures.
977 */
978 goto out;
979
980 /*
981 * Determine which debug features should be switched on
982 */
Pekka Enberg06428782008-01-07 23:20:27 -0800983 for (; *str && *str != ','; str++) {
Christoph Lameterf0630ff2007-07-15 23:38:14 -0700984 switch (tolower(*str)) {
985 case 'f':
986 slub_debug |= SLAB_DEBUG_FREE;
987 break;
988 case 'z':
989 slub_debug |= SLAB_RED_ZONE;
990 break;
991 case 'p':
992 slub_debug |= SLAB_POISON;
993 break;
994 case 'u':
995 slub_debug |= SLAB_STORE_USER;
996 break;
997 case 't':
998 slub_debug |= SLAB_TRACE;
999 break;
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +03001000 case 'a':
1001 slub_debug |= SLAB_FAILSLAB;
1002 break;
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001003 default:
1004 printk(KERN_ERR "slub_debug option '%c' "
Pekka Enberg06428782008-01-07 23:20:27 -08001005 "unknown. skipped\n", *str);
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001006 }
1007 }
1008
1009check_slabs:
1010 if (*str == ',')
Christoph Lameter41ecc552007-05-09 02:32:44 -07001011 slub_debug_slabs = str + 1;
Christoph Lameterf0630ff2007-07-15 23:38:14 -07001012out:
Christoph Lameter41ecc552007-05-09 02:32:44 -07001013 return 1;
1014}
1015
1016__setup("slub_debug", setup_slub_debug);
1017
Christoph Lameterba0268a2007-09-11 15:24:11 -07001018static unsigned long kmem_cache_flags(unsigned long objsize,
1019 unsigned long flags, const char *name,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001020 void (*ctor)(void *))
Christoph Lameter41ecc552007-05-09 02:32:44 -07001021{
1022 /*
Christoph Lametere1533622008-02-15 23:45:24 -08001023 * Enable debugging if selected on the kernel commandline.
Christoph Lameter41ecc552007-05-09 02:32:44 -07001024 */
Christoph Lametere1533622008-02-15 23:45:24 -08001025 if (slub_debug && (!slub_debug_slabs ||
David Rientjes3de47212009-07-27 18:30:35 -07001026 !strncmp(slub_debug_slabs, name, strlen(slub_debug_slabs))))
1027 flags |= slub_debug;
Christoph Lameterba0268a2007-09-11 15:24:11 -07001028
1029 return flags;
Christoph Lameter41ecc552007-05-09 02:32:44 -07001030}
1031#else
Christoph Lameter3ec09742007-05-16 22:11:00 -07001032static inline void setup_object_debug(struct kmem_cache *s,
1033 struct page *page, void *object) {}
Christoph Lameter41ecc552007-05-09 02:32:44 -07001034
Christoph Lameter3ec09742007-05-16 22:11:00 -07001035static inline int alloc_debug_processing(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001036 struct page *page, void *object, unsigned long addr) { return 0; }
Christoph Lameter41ecc552007-05-09 02:32:44 -07001037
Christoph Lameter3ec09742007-05-16 22:11:00 -07001038static inline int free_debug_processing(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001039 struct page *page, void *object, unsigned long addr) { return 0; }
Christoph Lameter41ecc552007-05-09 02:32:44 -07001040
Christoph Lameter41ecc552007-05-09 02:32:44 -07001041static inline int slab_pad_check(struct kmem_cache *s, struct page *page)
1042 { return 1; }
1043static inline int check_object(struct kmem_cache *s, struct page *page,
1044 void *object, int active) { return 1; }
Christoph Lameter3ec09742007-05-16 22:11:00 -07001045static inline void add_full(struct kmem_cache_node *n, struct page *page) {}
Christoph Lameterba0268a2007-09-11 15:24:11 -07001046static inline unsigned long kmem_cache_flags(unsigned long objsize,
1047 unsigned long flags, const char *name,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001048 void (*ctor)(void *))
Christoph Lameterba0268a2007-09-11 15:24:11 -07001049{
1050 return flags;
1051}
Christoph Lameter41ecc552007-05-09 02:32:44 -07001052#define slub_debug 0
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001053
Ingo Molnarfdaa45e2009-09-15 11:00:26 +02001054#define disable_higher_order_debug 0
1055
Christoph Lameter0f389ec2008-04-14 18:53:02 +03001056static inline unsigned long slabs_node(struct kmem_cache *s, int node)
1057 { return 0; }
Alexander Beregalov26c02cf2009-06-11 14:08:48 +04001058static inline unsigned long node_nr_slabs(struct kmem_cache_node *n)
1059 { return 0; }
Christoph Lameter205ab992008-04-14 19:11:40 +03001060static inline void inc_slabs_node(struct kmem_cache *s, int node,
1061 int objects) {}
1062static inline void dec_slabs_node(struct kmem_cache *s, int node,
1063 int objects) {}
Christoph Lameter41ecc552007-05-09 02:32:44 -07001064#endif
Christoph Lameter205ab992008-04-14 19:11:40 +03001065
Christoph Lameter81819f02007-05-06 14:49:36 -07001066/*
1067 * Slab allocation and freeing
1068 */
Christoph Lameter65c33762008-04-14 19:11:40 +03001069static inline struct page *alloc_slab_page(gfp_t flags, int node,
1070 struct kmem_cache_order_objects oo)
1071{
1072 int order = oo_order(oo);
1073
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001074 flags |= __GFP_NOTRACK;
1075
Christoph Lameter65c33762008-04-14 19:11:40 +03001076 if (node == -1)
1077 return alloc_pages(flags, order);
1078 else
Minchan Kim6b65aaf2010-04-14 23:58:36 +09001079 return alloc_pages_exact_node(node, flags, order);
Christoph Lameter65c33762008-04-14 19:11:40 +03001080}
1081
Christoph Lameter81819f02007-05-06 14:49:36 -07001082static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
1083{
Pekka Enberg06428782008-01-07 23:20:27 -08001084 struct page *page;
Christoph Lameter834f3d12008-04-14 19:11:31 +03001085 struct kmem_cache_order_objects oo = s->oo;
Pekka Enbergba522702009-06-24 21:59:51 +03001086 gfp_t alloc_gfp;
Christoph Lameter81819f02007-05-06 14:49:36 -07001087
Christoph Lameterb7a49f02008-02-14 14:21:32 -08001088 flags |= s->allocflags;
Mel Gormane12ba742007-10-16 01:25:52 -07001089
Pekka Enbergba522702009-06-24 21:59:51 +03001090 /*
1091 * Let the initial higher-order allocation fail under memory pressure
1092 * so we fall-back to the minimum order allocation.
1093 */
1094 alloc_gfp = (flags | __GFP_NOWARN | __GFP_NORETRY) & ~__GFP_NOFAIL;
1095
1096 page = alloc_slab_page(alloc_gfp, node, oo);
Christoph Lameter65c33762008-04-14 19:11:40 +03001097 if (unlikely(!page)) {
1098 oo = s->min;
1099 /*
1100 * Allocation may have failed due to fragmentation.
1101 * Try a lower order alloc if possible
1102 */
1103 page = alloc_slab_page(flags, node, oo);
1104 if (!page)
1105 return NULL;
Christoph Lameter81819f02007-05-06 14:49:36 -07001106
Christoph Lameter84e554e62009-12-18 16:26:23 -06001107 stat(s, ORDER_FALLBACK);
Christoph Lameter65c33762008-04-14 19:11:40 +03001108 }
Vegard Nossum5a896d92008-04-04 00:54:48 +02001109
1110 if (kmemcheck_enabled
Amerigo Wang5086c389c2009-08-19 21:44:13 +03001111 && !(s->flags & (SLAB_NOTRACK | DEBUG_DEFAULT_FLAGS))) {
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001112 int pages = 1 << oo_order(oo);
1113
1114 kmemcheck_alloc_shadow(page, oo_order(oo), flags, node);
1115
1116 /*
1117 * Objects from caches that have a constructor don't get
1118 * cleared when they're allocated, so we need to do it here.
1119 */
1120 if (s->ctor)
1121 kmemcheck_mark_uninitialized_pages(page, pages);
1122 else
1123 kmemcheck_mark_unallocated_pages(page, pages);
Vegard Nossum5a896d92008-04-04 00:54:48 +02001124 }
1125
Christoph Lameter834f3d12008-04-14 19:11:31 +03001126 page->objects = oo_objects(oo);
Christoph Lameter81819f02007-05-06 14:49:36 -07001127 mod_zone_page_state(page_zone(page),
1128 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
1129 NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
Christoph Lameter65c33762008-04-14 19:11:40 +03001130 1 << oo_order(oo));
Christoph Lameter81819f02007-05-06 14:49:36 -07001131
1132 return page;
1133}
1134
1135static void setup_object(struct kmem_cache *s, struct page *page,
1136 void *object)
1137{
Christoph Lameter3ec09742007-05-16 22:11:00 -07001138 setup_object_debug(s, page, object);
Christoph Lameter4f104932007-05-06 14:50:17 -07001139 if (unlikely(s->ctor))
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001140 s->ctor(object);
Christoph Lameter81819f02007-05-06 14:49:36 -07001141}
1142
1143static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
1144{
1145 struct page *page;
Christoph Lameter81819f02007-05-06 14:49:36 -07001146 void *start;
Christoph Lameter81819f02007-05-06 14:49:36 -07001147 void *last;
1148 void *p;
1149
Christoph Lameter6cb06222007-10-16 01:25:41 -07001150 BUG_ON(flags & GFP_SLAB_BUG_MASK);
Christoph Lameter81819f02007-05-06 14:49:36 -07001151
Christoph Lameter6cb06222007-10-16 01:25:41 -07001152 page = allocate_slab(s,
1153 flags & (GFP_RECLAIM_MASK | GFP_CONSTRAINT_MASK), node);
Christoph Lameter81819f02007-05-06 14:49:36 -07001154 if (!page)
1155 goto out;
1156
Christoph Lameter205ab992008-04-14 19:11:40 +03001157 inc_slabs_node(s, page_to_nid(page), page->objects);
Christoph Lameter81819f02007-05-06 14:49:36 -07001158 page->slab = s;
1159 page->flags |= 1 << PG_slab;
1160 if (s->flags & (SLAB_DEBUG_FREE | SLAB_RED_ZONE | SLAB_POISON |
1161 SLAB_STORE_USER | SLAB_TRACE))
Andy Whitcroft8a380822008-07-23 21:27:18 -07001162 __SetPageSlubDebug(page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001163
1164 start = page_address(page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001165
1166 if (unlikely(s->flags & SLAB_POISON))
Christoph Lameter834f3d12008-04-14 19:11:31 +03001167 memset(start, POISON_INUSE, PAGE_SIZE << compound_order(page));
Christoph Lameter81819f02007-05-06 14:49:36 -07001168
1169 last = start;
Christoph Lameter224a88b2008-04-14 19:11:31 +03001170 for_each_object(p, s, start, page->objects) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001171 setup_object(s, page, last);
1172 set_freepointer(s, last, p);
1173 last = p;
1174 }
1175 setup_object(s, page, last);
Christoph Lametera973e9d2008-03-01 13:40:44 -08001176 set_freepointer(s, last, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -07001177
1178 page->freelist = start;
1179 page->inuse = 0;
1180out:
Christoph Lameter81819f02007-05-06 14:49:36 -07001181 return page;
1182}
1183
1184static void __free_slab(struct kmem_cache *s, struct page *page)
1185{
Christoph Lameter834f3d12008-04-14 19:11:31 +03001186 int order = compound_order(page);
1187 int pages = 1 << order;
Christoph Lameter81819f02007-05-06 14:49:36 -07001188
Andy Whitcroft8a380822008-07-23 21:27:18 -07001189 if (unlikely(SLABDEBUG && PageSlubDebug(page))) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001190 void *p;
1191
1192 slab_pad_check(s, page);
Christoph Lameter224a88b2008-04-14 19:11:31 +03001193 for_each_object(p, s, page_address(page),
1194 page->objects)
Christoph Lameter81819f02007-05-06 14:49:36 -07001195 check_object(s, page, p, 0);
Andy Whitcroft8a380822008-07-23 21:27:18 -07001196 __ClearPageSlubDebug(page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001197 }
1198
Vegard Nossumb1eeab62008-11-25 16:55:53 +01001199 kmemcheck_free_shadow(page, compound_order(page));
Vegard Nossum5a896d92008-04-04 00:54:48 +02001200
Christoph Lameter81819f02007-05-06 14:49:36 -07001201 mod_zone_page_state(page_zone(page),
1202 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
1203 NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
Pekka Enberg06428782008-01-07 23:20:27 -08001204 -pages);
Christoph Lameter81819f02007-05-06 14:49:36 -07001205
Christoph Lameter49bd5222008-04-14 18:52:18 +03001206 __ClearPageSlab(page);
1207 reset_page_mapcount(page);
Nick Piggin1eb5ac62009-05-05 19:13:44 +10001208 if (current->reclaim_state)
1209 current->reclaim_state->reclaimed_slab += pages;
Christoph Lameter834f3d12008-04-14 19:11:31 +03001210 __free_pages(page, order);
Christoph Lameter81819f02007-05-06 14:49:36 -07001211}
1212
1213static void rcu_free_slab(struct rcu_head *h)
1214{
1215 struct page *page;
1216
1217 page = container_of((struct list_head *)h, struct page, lru);
1218 __free_slab(page->slab, page);
1219}
1220
1221static void free_slab(struct kmem_cache *s, struct page *page)
1222{
1223 if (unlikely(s->flags & SLAB_DESTROY_BY_RCU)) {
1224 /*
1225 * RCU free overloads the RCU head over the LRU
1226 */
1227 struct rcu_head *head = (void *)&page->lru;
1228
1229 call_rcu(head, rcu_free_slab);
1230 } else
1231 __free_slab(s, page);
1232}
1233
1234static void discard_slab(struct kmem_cache *s, struct page *page)
1235{
Christoph Lameter205ab992008-04-14 19:11:40 +03001236 dec_slabs_node(s, page_to_nid(page), page->objects);
Christoph Lameter81819f02007-05-06 14:49:36 -07001237 free_slab(s, page);
1238}
1239
1240/*
1241 * Per slab locking using the pagelock
1242 */
1243static __always_inline void slab_lock(struct page *page)
1244{
1245 bit_spin_lock(PG_locked, &page->flags);
1246}
1247
1248static __always_inline void slab_unlock(struct page *page)
1249{
Nick Piggina76d3542008-01-07 23:20:27 -08001250 __bit_spin_unlock(PG_locked, &page->flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07001251}
1252
1253static __always_inline int slab_trylock(struct page *page)
1254{
1255 int rc = 1;
1256
1257 rc = bit_spin_trylock(PG_locked, &page->flags);
1258 return rc;
1259}
1260
1261/*
1262 * Management of partially allocated slabs
1263 */
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001264static void add_partial(struct kmem_cache_node *n,
1265 struct page *page, int tail)
Christoph Lameter81819f02007-05-06 14:49:36 -07001266{
Christoph Lametere95eed52007-05-06 14:49:44 -07001267 spin_lock(&n->list_lock);
1268 n->nr_partial++;
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001269 if (tail)
1270 list_add_tail(&page->lru, &n->partial);
1271 else
1272 list_add(&page->lru, &n->partial);
Christoph Lameter81819f02007-05-06 14:49:36 -07001273 spin_unlock(&n->list_lock);
1274}
1275
Christoph Lameter0121c6192008-04-29 16:11:12 -07001276static void remove_partial(struct kmem_cache *s, struct page *page)
Christoph Lameter81819f02007-05-06 14:49:36 -07001277{
1278 struct kmem_cache_node *n = get_node(s, page_to_nid(page));
1279
1280 spin_lock(&n->list_lock);
1281 list_del(&page->lru);
1282 n->nr_partial--;
1283 spin_unlock(&n->list_lock);
1284}
1285
1286/*
Christoph Lameter672bba32007-05-09 02:32:39 -07001287 * Lock slab and remove from the partial list.
Christoph Lameter81819f02007-05-06 14:49:36 -07001288 *
Christoph Lameter672bba32007-05-09 02:32:39 -07001289 * Must hold list_lock.
Christoph Lameter81819f02007-05-06 14:49:36 -07001290 */
Christoph Lameter0121c6192008-04-29 16:11:12 -07001291static inline int lock_and_freeze_slab(struct kmem_cache_node *n,
1292 struct page *page)
Christoph Lameter81819f02007-05-06 14:49:36 -07001293{
1294 if (slab_trylock(page)) {
1295 list_del(&page->lru);
1296 n->nr_partial--;
Andy Whitcroft8a380822008-07-23 21:27:18 -07001297 __SetPageSlubFrozen(page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001298 return 1;
1299 }
1300 return 0;
1301}
1302
1303/*
Christoph Lameter672bba32007-05-09 02:32:39 -07001304 * Try to allocate a partial slab from a specific node.
Christoph Lameter81819f02007-05-06 14:49:36 -07001305 */
1306static struct page *get_partial_node(struct kmem_cache_node *n)
1307{
1308 struct page *page;
1309
1310 /*
1311 * Racy check. If we mistakenly see no partial slabs then we
1312 * just allocate an empty slab. If we mistakenly try to get a
Christoph Lameter672bba32007-05-09 02:32:39 -07001313 * partial slab and there is none available then get_partials()
1314 * will return NULL.
Christoph Lameter81819f02007-05-06 14:49:36 -07001315 */
1316 if (!n || !n->nr_partial)
1317 return NULL;
1318
1319 spin_lock(&n->list_lock);
1320 list_for_each_entry(page, &n->partial, lru)
Christoph Lameter4b6f0752007-05-16 22:10:53 -07001321 if (lock_and_freeze_slab(n, page))
Christoph Lameter81819f02007-05-06 14:49:36 -07001322 goto out;
1323 page = NULL;
1324out:
1325 spin_unlock(&n->list_lock);
1326 return page;
1327}
1328
1329/*
Christoph Lameter672bba32007-05-09 02:32:39 -07001330 * Get a page from somewhere. Search in increasing NUMA distances.
Christoph Lameter81819f02007-05-06 14:49:36 -07001331 */
1332static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags)
1333{
1334#ifdef CONFIG_NUMA
1335 struct zonelist *zonelist;
Mel Gormandd1a2392008-04-28 02:12:17 -07001336 struct zoneref *z;
Mel Gorman54a6eb52008-04-28 02:12:16 -07001337 struct zone *zone;
1338 enum zone_type high_zoneidx = gfp_zone(flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07001339 struct page *page;
1340
1341 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07001342 * The defrag ratio allows a configuration of the tradeoffs between
1343 * inter node defragmentation and node local allocations. A lower
1344 * defrag_ratio increases the tendency to do local allocations
1345 * instead of attempting to obtain partial slabs from other nodes.
Christoph Lameter81819f02007-05-06 14:49:36 -07001346 *
Christoph Lameter672bba32007-05-09 02:32:39 -07001347 * If the defrag_ratio is set to 0 then kmalloc() always
1348 * returns node local objects. If the ratio is higher then kmalloc()
1349 * may return off node objects because partial slabs are obtained
1350 * from other nodes and filled up.
Christoph Lameter81819f02007-05-06 14:49:36 -07001351 *
Christoph Lameter6446faa2008-02-15 23:45:26 -08001352 * If /sys/kernel/slab/xx/defrag_ratio is set to 100 (which makes
Christoph Lameter672bba32007-05-09 02:32:39 -07001353 * defrag_ratio = 1000) then every (well almost) allocation will
1354 * first attempt to defrag slab caches on other nodes. This means
1355 * scanning over all nodes to look for partial slabs which may be
1356 * expensive if we do it every time we are trying to find a slab
1357 * with available objects.
Christoph Lameter81819f02007-05-06 14:49:36 -07001358 */
Christoph Lameter98246012008-01-07 23:20:26 -08001359 if (!s->remote_node_defrag_ratio ||
1360 get_cycles() % 1024 > s->remote_node_defrag_ratio)
Christoph Lameter81819f02007-05-06 14:49:36 -07001361 return NULL;
1362
Miao Xiec0ff7452010-05-24 14:32:08 -07001363 get_mems_allowed();
Mel Gorman0e884602008-04-28 02:12:14 -07001364 zonelist = node_zonelist(slab_node(current->mempolicy), flags);
Mel Gorman54a6eb52008-04-28 02:12:16 -07001365 for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001366 struct kmem_cache_node *n;
1367
Mel Gorman54a6eb52008-04-28 02:12:16 -07001368 n = get_node(s, zone_to_nid(zone));
Christoph Lameter81819f02007-05-06 14:49:36 -07001369
Mel Gorman54a6eb52008-04-28 02:12:16 -07001370 if (n && cpuset_zone_allowed_hardwall(zone, flags) &&
David Rientjes3b89d7d2009-02-22 17:40:07 -08001371 n->nr_partial > s->min_partial) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001372 page = get_partial_node(n);
Miao Xiec0ff7452010-05-24 14:32:08 -07001373 if (page) {
1374 put_mems_allowed();
Christoph Lameter81819f02007-05-06 14:49:36 -07001375 return page;
Miao Xiec0ff7452010-05-24 14:32:08 -07001376 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001377 }
1378 }
Miao Xiec0ff7452010-05-24 14:32:08 -07001379 put_mems_allowed();
Christoph Lameter81819f02007-05-06 14:49:36 -07001380#endif
1381 return NULL;
1382}
1383
1384/*
1385 * Get a partial page, lock it and return it.
1386 */
1387static struct page *get_partial(struct kmem_cache *s, gfp_t flags, int node)
1388{
1389 struct page *page;
1390 int searchnode = (node == -1) ? numa_node_id() : node;
1391
1392 page = get_partial_node(get_node(s, searchnode));
1393 if (page || (flags & __GFP_THISNODE))
1394 return page;
1395
1396 return get_any_partial(s, flags);
1397}
1398
1399/*
1400 * Move a page back to the lists.
1401 *
1402 * Must be called with the slab lock held.
1403 *
1404 * On exit the slab lock will have been dropped.
1405 */
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001406static void unfreeze_slab(struct kmem_cache *s, struct page *page, int tail)
Christoph Lameter81819f02007-05-06 14:49:36 -07001407{
Christoph Lametere95eed52007-05-06 14:49:44 -07001408 struct kmem_cache_node *n = get_node(s, page_to_nid(page));
1409
Andy Whitcroft8a380822008-07-23 21:27:18 -07001410 __ClearPageSlubFrozen(page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001411 if (page->inuse) {
Christoph Lametere95eed52007-05-06 14:49:44 -07001412
Christoph Lametera973e9d2008-03-01 13:40:44 -08001413 if (page->freelist) {
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001414 add_partial(n, page, tail);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001415 stat(s, tail ? DEACTIVATE_TO_TAIL : DEACTIVATE_TO_HEAD);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08001416 } else {
Christoph Lameter84e554e62009-12-18 16:26:23 -06001417 stat(s, DEACTIVATE_FULL);
Andy Whitcroft8a380822008-07-23 21:27:18 -07001418 if (SLABDEBUG && PageSlubDebug(page) &&
1419 (s->flags & SLAB_STORE_USER))
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08001420 add_full(n, page);
1421 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001422 slab_unlock(page);
1423 } else {
Christoph Lameter84e554e62009-12-18 16:26:23 -06001424 stat(s, DEACTIVATE_EMPTY);
David Rientjes3b89d7d2009-02-22 17:40:07 -08001425 if (n->nr_partial < s->min_partial) {
Christoph Lametere95eed52007-05-06 14:49:44 -07001426 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07001427 * Adding an empty slab to the partial slabs in order
1428 * to avoid page allocator overhead. This slab needs
1429 * to come after the other slabs with objects in
Christoph Lameter6446faa2008-02-15 23:45:26 -08001430 * so that the others get filled first. That way the
1431 * size of the partial list stays small.
1432 *
Christoph Lameter0121c6192008-04-29 16:11:12 -07001433 * kmem_cache_shrink can reclaim any empty slabs from
1434 * the partial list.
Christoph Lametere95eed52007-05-06 14:49:44 -07001435 */
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001436 add_partial(n, page, 1);
Christoph Lametere95eed52007-05-06 14:49:44 -07001437 slab_unlock(page);
1438 } else {
1439 slab_unlock(page);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001440 stat(s, FREE_SLAB);
Christoph Lametere95eed52007-05-06 14:49:44 -07001441 discard_slab(s, page);
1442 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001443 }
1444}
1445
1446/*
1447 * Remove the cpu slab
1448 */
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001449static void deactivate_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07001450{
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001451 struct page *page = c->page;
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001452 int tail = 1;
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08001453
Christoph Lameterb773ad72008-03-04 11:10:17 -08001454 if (page->freelist)
Christoph Lameter84e554e62009-12-18 16:26:23 -06001455 stat(s, DEACTIVATE_REMOTE_FREES);
Christoph Lameter894b8782007-05-10 03:15:16 -07001456 /*
Christoph Lameter6446faa2008-02-15 23:45:26 -08001457 * Merge cpu freelist into slab freelist. Typically we get here
Christoph Lameter894b8782007-05-10 03:15:16 -07001458 * because both freelists are empty. So this is unlikely
1459 * to occur.
1460 */
Christoph Lametera973e9d2008-03-01 13:40:44 -08001461 while (unlikely(c->freelist)) {
Christoph Lameter894b8782007-05-10 03:15:16 -07001462 void **object;
1463
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001464 tail = 0; /* Hot objects. Put the slab first */
1465
Christoph Lameter894b8782007-05-10 03:15:16 -07001466 /* Retrieve object from cpu_freelist */
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001467 object = c->freelist;
Christoph Lameterff120592009-12-18 16:26:22 -06001468 c->freelist = get_freepointer(s, c->freelist);
Christoph Lameter894b8782007-05-10 03:15:16 -07001469
1470 /* And put onto the regular freelist */
Christoph Lameterff120592009-12-18 16:26:22 -06001471 set_freepointer(s, object, page->freelist);
Christoph Lameter894b8782007-05-10 03:15:16 -07001472 page->freelist = object;
1473 page->inuse--;
1474 }
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001475 c->page = NULL;
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001476 unfreeze_slab(s, page, tail);
Christoph Lameter81819f02007-05-06 14:49:36 -07001477}
1478
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001479static inline void flush_slab(struct kmem_cache *s, struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07001480{
Christoph Lameter84e554e62009-12-18 16:26:23 -06001481 stat(s, CPUSLAB_FLUSH);
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001482 slab_lock(c->page);
1483 deactivate_slab(s, c);
Christoph Lameter81819f02007-05-06 14:49:36 -07001484}
1485
1486/*
1487 * Flush cpu slab.
Christoph Lameter6446faa2008-02-15 23:45:26 -08001488 *
Christoph Lameter81819f02007-05-06 14:49:36 -07001489 * Called from IPI handler with interrupts disabled.
1490 */
Christoph Lameter0c710012007-07-17 04:03:24 -07001491static inline void __flush_cpu_slab(struct kmem_cache *s, int cpu)
Christoph Lameter81819f02007-05-06 14:49:36 -07001492{
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06001493 struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
Christoph Lameter81819f02007-05-06 14:49:36 -07001494
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001495 if (likely(c && c->page))
1496 flush_slab(s, c);
Christoph Lameter81819f02007-05-06 14:49:36 -07001497}
1498
1499static void flush_cpu_slab(void *d)
1500{
1501 struct kmem_cache *s = d;
Christoph Lameter81819f02007-05-06 14:49:36 -07001502
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001503 __flush_cpu_slab(s, smp_processor_id());
Christoph Lameter81819f02007-05-06 14:49:36 -07001504}
1505
1506static void flush_all(struct kmem_cache *s)
1507{
Jens Axboe15c8b6c2008-05-09 09:39:44 +02001508 on_each_cpu(flush_cpu_slab, s, 1);
Christoph Lameter81819f02007-05-06 14:49:36 -07001509}
1510
1511/*
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001512 * Check if the objects in a per cpu structure fit numa
1513 * locality expectations.
1514 */
1515static inline int node_match(struct kmem_cache_cpu *c, int node)
1516{
1517#ifdef CONFIG_NUMA
1518 if (node != -1 && c->node != node)
1519 return 0;
1520#endif
1521 return 1;
1522}
1523
Pekka Enberg781b2ba2009-06-10 18:50:32 +03001524static int count_free(struct page *page)
1525{
1526 return page->objects - page->inuse;
1527}
1528
1529static unsigned long count_partial(struct kmem_cache_node *n,
1530 int (*get_count)(struct page *))
1531{
1532 unsigned long flags;
1533 unsigned long x = 0;
1534 struct page *page;
1535
1536 spin_lock_irqsave(&n->list_lock, flags);
1537 list_for_each_entry(page, &n->partial, lru)
1538 x += get_count(page);
1539 spin_unlock_irqrestore(&n->list_lock, flags);
1540 return x;
1541}
1542
Alexander Beregalov26c02cf2009-06-11 14:08:48 +04001543static inline unsigned long node_nr_objs(struct kmem_cache_node *n)
1544{
1545#ifdef CONFIG_SLUB_DEBUG
1546 return atomic_long_read(&n->total_objects);
1547#else
1548 return 0;
1549#endif
1550}
1551
Pekka Enberg781b2ba2009-06-10 18:50:32 +03001552static noinline void
1553slab_out_of_memory(struct kmem_cache *s, gfp_t gfpflags, int nid)
1554{
1555 int node;
1556
1557 printk(KERN_WARNING
1558 "SLUB: Unable to allocate memory on node %d (gfp=0x%x)\n",
1559 nid, gfpflags);
1560 printk(KERN_WARNING " cache: %s, object size: %d, buffer size: %d, "
1561 "default order: %d, min order: %d\n", s->name, s->objsize,
1562 s->size, oo_order(s->oo), oo_order(s->min));
1563
David Rientjesfa5ec8a2009-07-07 00:14:14 -07001564 if (oo_order(s->min) > get_order(s->objsize))
1565 printk(KERN_WARNING " %s debugging increased min order, use "
1566 "slub_debug=O to disable.\n", s->name);
1567
Pekka Enberg781b2ba2009-06-10 18:50:32 +03001568 for_each_online_node(node) {
1569 struct kmem_cache_node *n = get_node(s, node);
1570 unsigned long nr_slabs;
1571 unsigned long nr_objs;
1572 unsigned long nr_free;
1573
1574 if (!n)
1575 continue;
1576
Alexander Beregalov26c02cf2009-06-11 14:08:48 +04001577 nr_free = count_partial(n, count_free);
1578 nr_slabs = node_nr_slabs(n);
1579 nr_objs = node_nr_objs(n);
Pekka Enberg781b2ba2009-06-10 18:50:32 +03001580
1581 printk(KERN_WARNING
1582 " node %d: slabs: %ld, objs: %ld, free: %ld\n",
1583 node, nr_slabs, nr_objs, nr_free);
1584 }
1585}
1586
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001587/*
Christoph Lameter894b8782007-05-10 03:15:16 -07001588 * Slow path. The lockless freelist is empty or we need to perform
1589 * debugging duties.
Christoph Lameter81819f02007-05-06 14:49:36 -07001590 *
Christoph Lameter894b8782007-05-10 03:15:16 -07001591 * Interrupts are disabled.
Christoph Lameter81819f02007-05-06 14:49:36 -07001592 *
Christoph Lameter894b8782007-05-10 03:15:16 -07001593 * Processing is still very fast if new objects have been freed to the
1594 * regular freelist. In that case we simply take over the regular freelist
1595 * as the lockless freelist and zap the regular freelist.
Christoph Lameter81819f02007-05-06 14:49:36 -07001596 *
Christoph Lameter894b8782007-05-10 03:15:16 -07001597 * If that is not working then we fall back to the partial lists. We take the
1598 * first element of the freelist as the object to allocate now and move the
1599 * rest of the freelist to the lockless freelist.
1600 *
1601 * And if we were unable to get a new slab from the partial slab lists then
Christoph Lameter6446faa2008-02-15 23:45:26 -08001602 * we need to allocate a new slab. This is the slowest path since it involves
1603 * a call to the page allocator and the setup of a new slab.
Christoph Lameter81819f02007-05-06 14:49:36 -07001604 */
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001605static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node,
1606 unsigned long addr, struct kmem_cache_cpu *c)
Christoph Lameter81819f02007-05-06 14:49:36 -07001607{
Christoph Lameter81819f02007-05-06 14:49:36 -07001608 void **object;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001609 struct page *new;
Christoph Lameter81819f02007-05-06 14:49:36 -07001610
Linus Torvaldse72e9c22008-03-27 20:56:33 -07001611 /* We handle __GFP_ZERO in the caller */
1612 gfpflags &= ~__GFP_ZERO;
1613
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001614 if (!c->page)
Christoph Lameter81819f02007-05-06 14:49:36 -07001615 goto new_slab;
1616
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001617 slab_lock(c->page);
1618 if (unlikely(!node_match(c, node)))
Christoph Lameter81819f02007-05-06 14:49:36 -07001619 goto another_slab;
Christoph Lameter6446faa2008-02-15 23:45:26 -08001620
Christoph Lameter84e554e62009-12-18 16:26:23 -06001621 stat(s, ALLOC_REFILL);
Christoph Lameter6446faa2008-02-15 23:45:26 -08001622
Christoph Lameter894b8782007-05-10 03:15:16 -07001623load_freelist:
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001624 object = c->page->freelist;
Christoph Lametera973e9d2008-03-01 13:40:44 -08001625 if (unlikely(!object))
Christoph Lameter81819f02007-05-06 14:49:36 -07001626 goto another_slab;
Andy Whitcroft8a380822008-07-23 21:27:18 -07001627 if (unlikely(SLABDEBUG && PageSlubDebug(c->page)))
Christoph Lameter81819f02007-05-06 14:49:36 -07001628 goto debug;
1629
Christoph Lameterff120592009-12-18 16:26:22 -06001630 c->freelist = get_freepointer(s, object);
Christoph Lameter39b26462008-04-14 19:11:30 +03001631 c->page->inuse = c->page->objects;
Christoph Lametera973e9d2008-03-01 13:40:44 -08001632 c->page->freelist = NULL;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001633 c->node = page_to_nid(c->page);
Christoph Lameter1f842602008-01-07 23:20:30 -08001634unlock_out:
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001635 slab_unlock(c->page);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001636 stat(s, ALLOC_SLOWPATH);
Christoph Lameter81819f02007-05-06 14:49:36 -07001637 return object;
1638
1639another_slab:
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001640 deactivate_slab(s, c);
Christoph Lameter81819f02007-05-06 14:49:36 -07001641
1642new_slab:
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001643 new = get_partial(s, gfpflags, node);
1644 if (new) {
1645 c->page = new;
Christoph Lameter84e554e62009-12-18 16:26:23 -06001646 stat(s, ALLOC_FROM_PARTIAL);
Christoph Lameter894b8782007-05-10 03:15:16 -07001647 goto load_freelist;
Christoph Lameter81819f02007-05-06 14:49:36 -07001648 }
1649
Christoph Lameterb811c202007-10-16 23:25:51 -07001650 if (gfpflags & __GFP_WAIT)
1651 local_irq_enable();
1652
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001653 new = new_slab(s, gfpflags, node);
Christoph Lameterb811c202007-10-16 23:25:51 -07001654
1655 if (gfpflags & __GFP_WAIT)
1656 local_irq_disable();
1657
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001658 if (new) {
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06001659 c = __this_cpu_ptr(s->cpu_slab);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001660 stat(s, ALLOC_SLAB);
Christoph Lameter05aa3452007-11-05 11:31:58 -08001661 if (c->page)
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001662 flush_slab(s, c);
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001663 slab_lock(new);
Andy Whitcroft8a380822008-07-23 21:27:18 -07001664 __SetPageSlubFrozen(new);
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001665 c->page = new;
Christoph Lameter4b6f0752007-05-16 22:10:53 -07001666 goto load_freelist;
Christoph Lameter81819f02007-05-06 14:49:36 -07001667 }
Pekka Enberg95f85982009-06-11 16:18:09 +03001668 if (!(gfpflags & __GFP_NOWARN) && printk_ratelimit())
1669 slab_out_of_memory(s, gfpflags, node);
Christoph Lameter71c7a062008-02-14 14:28:01 -08001670 return NULL;
Christoph Lameter81819f02007-05-06 14:49:36 -07001671debug:
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001672 if (!alloc_debug_processing(s, c->page, object, addr))
Christoph Lameter81819f02007-05-06 14:49:36 -07001673 goto another_slab;
Christoph Lameter894b8782007-05-10 03:15:16 -07001674
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001675 c->page->inuse++;
Christoph Lameterff120592009-12-18 16:26:22 -06001676 c->page->freelist = get_freepointer(s, object);
Christoph Lameteree3c72a2007-10-16 01:26:07 -07001677 c->node = -1;
Christoph Lameter1f842602008-01-07 23:20:30 -08001678 goto unlock_out;
Christoph Lameter894b8782007-05-10 03:15:16 -07001679}
1680
1681/*
1682 * Inlined fastpath so that allocation functions (kmalloc, kmem_cache_alloc)
1683 * have the fastpath folded into their functions. So no function call
1684 * overhead for requests that can be satisfied on the fastpath.
1685 *
1686 * The fastpath works by first checking if the lockless freelist can be used.
1687 * If not then __slab_alloc is called for slow processing.
1688 *
1689 * Otherwise we can simply pick the next object from the lockless free list.
1690 */
Pekka Enberg06428782008-01-07 23:20:27 -08001691static __always_inline void *slab_alloc(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001692 gfp_t gfpflags, int node, unsigned long addr)
Christoph Lameter894b8782007-05-10 03:15:16 -07001693{
Christoph Lameter894b8782007-05-10 03:15:16 -07001694 void **object;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001695 struct kmem_cache_cpu *c;
Christoph Lameter1f842602008-01-07 23:20:30 -08001696 unsigned long flags;
1697
Benjamin Herrenschmidtdcce2842009-06-18 13:24:12 +10001698 gfpflags &= gfp_allowed_mask;
Pekka Enberg7e85ee02009-06-12 14:03:06 +03001699
Nick Piggincf40bd12009-01-21 08:12:39 +01001700 lockdep_trace_alloc(gfpflags);
OGAWA Hirofumi89124d72008-11-19 21:23:59 +09001701 might_sleep_if(gfpflags & __GFP_WAIT);
Pekka Enberg3c506ef2008-12-29 11:47:05 +02001702
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +03001703 if (should_failslab(s->objsize, gfpflags, s->flags))
Akinobu Mita773ff602008-12-23 19:37:01 +09001704 return NULL;
1705
Christoph Lameter894b8782007-05-10 03:15:16 -07001706 local_irq_save(flags);
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06001707 c = __this_cpu_ptr(s->cpu_slab);
1708 object = c->freelist;
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06001709 if (unlikely(!object || !node_match(c, node)))
Christoph Lameter894b8782007-05-10 03:15:16 -07001710
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001711 object = __slab_alloc(s, gfpflags, node, addr, c);
Christoph Lameter894b8782007-05-10 03:15:16 -07001712
1713 else {
Christoph Lameterff120592009-12-18 16:26:22 -06001714 c->freelist = get_freepointer(s, object);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001715 stat(s, ALLOC_FASTPATH);
Christoph Lameter894b8782007-05-10 03:15:16 -07001716 }
1717 local_irq_restore(flags);
Christoph Lameterd07dbea2007-07-17 04:03:23 -07001718
Pekka Enberg74e21342009-11-25 20:14:48 +02001719 if (unlikely(gfpflags & __GFP_ZERO) && object)
Christoph Lameterff120592009-12-18 16:26:22 -06001720 memset(object, 0, s->objsize);
Christoph Lameterd07dbea2007-07-17 04:03:23 -07001721
Christoph Lameterff120592009-12-18 16:26:22 -06001722 kmemcheck_slab_alloc(s, gfpflags, object, s->objsize);
1723 kmemleak_alloc_recursive(object, s->objsize, 1, s->flags, gfpflags);
Vegard Nossum5a896d92008-04-04 00:54:48 +02001724
Christoph Lameter894b8782007-05-10 03:15:16 -07001725 return object;
Christoph Lameter81819f02007-05-06 14:49:36 -07001726}
1727
1728void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags)
1729{
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001730 void *ret = slab_alloc(s, gfpflags, -1, _RET_IP_);
1731
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02001732 trace_kmem_cache_alloc(_RET_IP_, ret, s->objsize, s->size, gfpflags);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001733
1734 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07001735}
1736EXPORT_SYMBOL(kmem_cache_alloc);
1737
Li Zefan0f24f122009-12-11 15:45:30 +08001738#ifdef CONFIG_TRACING
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001739void *kmem_cache_alloc_notrace(struct kmem_cache *s, gfp_t gfpflags)
1740{
1741 return slab_alloc(s, gfpflags, -1, _RET_IP_);
1742}
1743EXPORT_SYMBOL(kmem_cache_alloc_notrace);
1744#endif
1745
Christoph Lameter81819f02007-05-06 14:49:36 -07001746#ifdef CONFIG_NUMA
1747void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node)
1748{
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001749 void *ret = slab_alloc(s, gfpflags, node, _RET_IP_);
1750
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02001751 trace_kmem_cache_alloc_node(_RET_IP_, ret,
1752 s->objsize, s->size, gfpflags, node);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001753
1754 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07001755}
1756EXPORT_SYMBOL(kmem_cache_alloc_node);
1757#endif
1758
Li Zefan0f24f122009-12-11 15:45:30 +08001759#ifdef CONFIG_TRACING
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001760void *kmem_cache_alloc_node_notrace(struct kmem_cache *s,
1761 gfp_t gfpflags,
1762 int node)
1763{
1764 return slab_alloc(s, gfpflags, node, _RET_IP_);
1765}
1766EXPORT_SYMBOL(kmem_cache_alloc_node_notrace);
1767#endif
1768
Christoph Lameter81819f02007-05-06 14:49:36 -07001769/*
Christoph Lameter894b8782007-05-10 03:15:16 -07001770 * Slow patch handling. This may still be called frequently since objects
1771 * have a longer lifetime than the cpu slabs in most processing loads.
Christoph Lameter81819f02007-05-06 14:49:36 -07001772 *
Christoph Lameter894b8782007-05-10 03:15:16 -07001773 * So we still attempt to reduce cache line usage. Just take the slab
1774 * lock and free the item. If there is no additional partial page
1775 * handling required then we can return immediately.
Christoph Lameter81819f02007-05-06 14:49:36 -07001776 */
Christoph Lameter894b8782007-05-10 03:15:16 -07001777static void __slab_free(struct kmem_cache *s, struct page *page,
Christoph Lameterff120592009-12-18 16:26:22 -06001778 void *x, unsigned long addr)
Christoph Lameter81819f02007-05-06 14:49:36 -07001779{
1780 void *prior;
1781 void **object = (void *)x;
Christoph Lameter81819f02007-05-06 14:49:36 -07001782
Christoph Lameter84e554e62009-12-18 16:26:23 -06001783 stat(s, FREE_SLOWPATH);
Christoph Lameter81819f02007-05-06 14:49:36 -07001784 slab_lock(page);
1785
Andy Whitcroft8a380822008-07-23 21:27:18 -07001786 if (unlikely(SLABDEBUG && PageSlubDebug(page)))
Christoph Lameter81819f02007-05-06 14:49:36 -07001787 goto debug;
Christoph Lameter6446faa2008-02-15 23:45:26 -08001788
Christoph Lameter81819f02007-05-06 14:49:36 -07001789checks_ok:
Christoph Lameterff120592009-12-18 16:26:22 -06001790 prior = page->freelist;
1791 set_freepointer(s, object, prior);
Christoph Lameter81819f02007-05-06 14:49:36 -07001792 page->freelist = object;
1793 page->inuse--;
1794
Andy Whitcroft8a380822008-07-23 21:27:18 -07001795 if (unlikely(PageSlubFrozen(page))) {
Christoph Lameter84e554e62009-12-18 16:26:23 -06001796 stat(s, FREE_FROZEN);
Christoph Lameter81819f02007-05-06 14:49:36 -07001797 goto out_unlock;
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08001798 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001799
1800 if (unlikely(!page->inuse))
1801 goto slab_empty;
1802
1803 /*
Christoph Lameter6446faa2008-02-15 23:45:26 -08001804 * Objects left in the slab. If it was not on the partial list before
Christoph Lameter81819f02007-05-06 14:49:36 -07001805 * then add it.
1806 */
Christoph Lametera973e9d2008-03-01 13:40:44 -08001807 if (unlikely(!prior)) {
Christoph Lameter7c2e1322008-01-07 23:20:27 -08001808 add_partial(get_node(s, page_to_nid(page)), page, 1);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001809 stat(s, FREE_ADD_PARTIAL);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08001810 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001811
1812out_unlock:
1813 slab_unlock(page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001814 return;
1815
1816slab_empty:
Christoph Lametera973e9d2008-03-01 13:40:44 -08001817 if (prior) {
Christoph Lameter81819f02007-05-06 14:49:36 -07001818 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07001819 * Slab still on the partial list.
Christoph Lameter81819f02007-05-06 14:49:36 -07001820 */
1821 remove_partial(s, page);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001822 stat(s, FREE_REMOVE_PARTIAL);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08001823 }
Christoph Lameter81819f02007-05-06 14:49:36 -07001824 slab_unlock(page);
Christoph Lameter84e554e62009-12-18 16:26:23 -06001825 stat(s, FREE_SLAB);
Christoph Lameter81819f02007-05-06 14:49:36 -07001826 discard_slab(s, page);
Christoph Lameter81819f02007-05-06 14:49:36 -07001827 return;
1828
1829debug:
Christoph Lameter3ec09742007-05-16 22:11:00 -07001830 if (!free_debug_processing(s, page, x, addr))
Christoph Lameter77c5e2d2007-05-06 14:49:42 -07001831 goto out_unlock;
Christoph Lameter77c5e2d2007-05-06 14:49:42 -07001832 goto checks_ok;
Christoph Lameter81819f02007-05-06 14:49:36 -07001833}
1834
Christoph Lameter894b8782007-05-10 03:15:16 -07001835/*
1836 * Fastpath with forced inlining to produce a kfree and kmem_cache_free that
1837 * can perform fastpath freeing without additional function calls.
1838 *
1839 * The fastpath is only possible if we are freeing to the current cpu slab
1840 * of this processor. This typically the case if we have just allocated
1841 * the item before.
1842 *
1843 * If fastpath is not possible then fall back to __slab_free where we deal
1844 * with all sorts of special processing.
1845 */
Pekka Enberg06428782008-01-07 23:20:27 -08001846static __always_inline void slab_free(struct kmem_cache *s,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001847 struct page *page, void *x, unsigned long addr)
Christoph Lameter894b8782007-05-10 03:15:16 -07001848{
1849 void **object = (void *)x;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001850 struct kmem_cache_cpu *c;
Christoph Lameter1f842602008-01-07 23:20:30 -08001851 unsigned long flags;
1852
Catalin Marinas06f22f12009-06-11 13:23:18 +01001853 kmemleak_free_recursive(x, s->flags);
Christoph Lameter894b8782007-05-10 03:15:16 -07001854 local_irq_save(flags);
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06001855 c = __this_cpu_ptr(s->cpu_slab);
Christoph Lameterff120592009-12-18 16:26:22 -06001856 kmemcheck_slab_free(s, object, s->objsize);
1857 debug_check_no_locks_freed(object, s->objsize);
Thomas Gleixner3ac7fe52008-04-30 00:55:01 -07001858 if (!(s->flags & SLAB_DEBUG_OBJECTS))
Christoph Lameterff120592009-12-18 16:26:22 -06001859 debug_check_no_obj_freed(object, s->objsize);
Christoph Lameteree3c72a2007-10-16 01:26:07 -07001860 if (likely(page == c->page && c->node >= 0)) {
Christoph Lameterff120592009-12-18 16:26:22 -06001861 set_freepointer(s, object, c->freelist);
Christoph Lameterdfb4f092007-10-16 01:26:05 -07001862 c->freelist = object;
Christoph Lameter84e554e62009-12-18 16:26:23 -06001863 stat(s, FREE_FASTPATH);
Christoph Lameter894b8782007-05-10 03:15:16 -07001864 } else
Christoph Lameterff120592009-12-18 16:26:22 -06001865 __slab_free(s, page, x, addr);
Christoph Lameter894b8782007-05-10 03:15:16 -07001866
1867 local_irq_restore(flags);
1868}
1869
Christoph Lameter81819f02007-05-06 14:49:36 -07001870void kmem_cache_free(struct kmem_cache *s, void *x)
1871{
Christoph Lameter77c5e2d2007-05-06 14:49:42 -07001872 struct page *page;
Christoph Lameter81819f02007-05-06 14:49:36 -07001873
Christoph Lameterb49af682007-05-06 14:49:41 -07001874 page = virt_to_head_page(x);
Christoph Lameter81819f02007-05-06 14:49:36 -07001875
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03001876 slab_free(s, page, x, _RET_IP_);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03001877
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02001878 trace_kmem_cache_free(_RET_IP_, x);
Christoph Lameter81819f02007-05-06 14:49:36 -07001879}
1880EXPORT_SYMBOL(kmem_cache_free);
1881
Cyrill Gorcunove9beef12008-10-28 22:02:26 +03001882/* Figure out on which slab page the object resides */
Christoph Lameter81819f02007-05-06 14:49:36 -07001883static struct page *get_object_page(const void *x)
1884{
Christoph Lameterb49af682007-05-06 14:49:41 -07001885 struct page *page = virt_to_head_page(x);
Christoph Lameter81819f02007-05-06 14:49:36 -07001886
1887 if (!PageSlab(page))
1888 return NULL;
1889
1890 return page;
1891}
1892
1893/*
Christoph Lameter672bba32007-05-09 02:32:39 -07001894 * Object placement in a slab is made very easy because we always start at
1895 * offset 0. If we tune the size of the object to the alignment then we can
1896 * get the required alignment by putting one properly sized object after
1897 * another.
Christoph Lameter81819f02007-05-06 14:49:36 -07001898 *
1899 * Notice that the allocation order determines the sizes of the per cpu
1900 * caches. Each processor has always one slab available for allocations.
1901 * Increasing the allocation order reduces the number of times that slabs
Christoph Lameter672bba32007-05-09 02:32:39 -07001902 * must be moved on and off the partial lists and is therefore a factor in
Christoph Lameter81819f02007-05-06 14:49:36 -07001903 * locking overhead.
Christoph Lameter81819f02007-05-06 14:49:36 -07001904 */
1905
1906/*
1907 * Mininum / Maximum order of slab pages. This influences locking overhead
1908 * and slab fragmentation. A higher order reduces the number of partial slabs
1909 * and increases the number of allocations possible without having to
1910 * take the list_lock.
1911 */
1912static int slub_min_order;
Christoph Lameter114e9e82008-04-14 19:11:41 +03001913static int slub_max_order = PAGE_ALLOC_COSTLY_ORDER;
Christoph Lameter9b2cd502008-04-14 19:11:41 +03001914static int slub_min_objects;
Christoph Lameter81819f02007-05-06 14:49:36 -07001915
1916/*
1917 * Merge control. If this is set then no merging of slab caches will occur.
Christoph Lameter672bba32007-05-09 02:32:39 -07001918 * (Could be removed. This was introduced to pacify the merge skeptics.)
Christoph Lameter81819f02007-05-06 14:49:36 -07001919 */
1920static int slub_nomerge;
1921
1922/*
Christoph Lameter81819f02007-05-06 14:49:36 -07001923 * Calculate the order of allocation given an slab object size.
1924 *
Christoph Lameter672bba32007-05-09 02:32:39 -07001925 * The order of allocation has significant impact on performance and other
1926 * system components. Generally order 0 allocations should be preferred since
1927 * order 0 does not cause fragmentation in the page allocator. Larger objects
1928 * be problematic to put into order 0 slabs because there may be too much
Christoph Lameterc124f5b2008-04-14 19:13:29 +03001929 * unused space left. We go to a higher order if more than 1/16th of the slab
Christoph Lameter672bba32007-05-09 02:32:39 -07001930 * would be wasted.
Christoph Lameter81819f02007-05-06 14:49:36 -07001931 *
Christoph Lameter672bba32007-05-09 02:32:39 -07001932 * In order to reach satisfactory performance we must ensure that a minimum
1933 * number of objects is in one slab. Otherwise we may generate too much
1934 * activity on the partial lists which requires taking the list_lock. This is
1935 * less a concern for large slabs though which are rarely used.
Christoph Lameter81819f02007-05-06 14:49:36 -07001936 *
Christoph Lameter672bba32007-05-09 02:32:39 -07001937 * slub_max_order specifies the order where we begin to stop considering the
1938 * number of objects in a slab as critical. If we reach slub_max_order then
1939 * we try to keep the page order as low as possible. So we accept more waste
1940 * of space in favor of a small page order.
1941 *
1942 * Higher order allocations also allow the placement of more objects in a
1943 * slab and thereby reduce object handling overhead. If the user has
1944 * requested a higher mininum order then we start with that one instead of
1945 * the smallest order which will fit the object.
Christoph Lameter81819f02007-05-06 14:49:36 -07001946 */
Christoph Lameter5e6d4442007-05-09 02:32:46 -07001947static inline int slab_order(int size, int min_objects,
1948 int max_order, int fract_leftover)
Christoph Lameter81819f02007-05-06 14:49:36 -07001949{
1950 int order;
1951 int rem;
Christoph Lameter6300ea72007-07-17 04:03:20 -07001952 int min_order = slub_min_order;
Christoph Lameter81819f02007-05-06 14:49:36 -07001953
Cyrill Gorcunov210b5c02008-10-22 23:00:38 +04001954 if ((PAGE_SIZE << min_order) / size > MAX_OBJS_PER_PAGE)
1955 return get_order(size * MAX_OBJS_PER_PAGE) - 1;
Christoph Lameter39b26462008-04-14 19:11:30 +03001956
Christoph Lameter6300ea72007-07-17 04:03:20 -07001957 for (order = max(min_order,
Christoph Lameter5e6d4442007-05-09 02:32:46 -07001958 fls(min_objects * size - 1) - PAGE_SHIFT);
1959 order <= max_order; order++) {
1960
Christoph Lameter81819f02007-05-06 14:49:36 -07001961 unsigned long slab_size = PAGE_SIZE << order;
1962
Christoph Lameter5e6d4442007-05-09 02:32:46 -07001963 if (slab_size < min_objects * size)
Christoph Lameter81819f02007-05-06 14:49:36 -07001964 continue;
1965
Christoph Lameter81819f02007-05-06 14:49:36 -07001966 rem = slab_size % size;
1967
Christoph Lameter5e6d4442007-05-09 02:32:46 -07001968 if (rem <= slab_size / fract_leftover)
Christoph Lameter81819f02007-05-06 14:49:36 -07001969 break;
1970
1971 }
Christoph Lameter672bba32007-05-09 02:32:39 -07001972
Christoph Lameter81819f02007-05-06 14:49:36 -07001973 return order;
1974}
1975
Christoph Lameter5e6d4442007-05-09 02:32:46 -07001976static inline int calculate_order(int size)
1977{
1978 int order;
1979 int min_objects;
1980 int fraction;
Zhang Yanmine8120ff2009-02-12 18:00:17 +02001981 int max_objects;
Christoph Lameter5e6d4442007-05-09 02:32:46 -07001982
1983 /*
1984 * Attempt to find best configuration for a slab. This
1985 * works by first attempting to generate a layout with
1986 * the best configuration and backing off gradually.
1987 *
1988 * First we reduce the acceptable waste in a slab. Then
1989 * we reduce the minimum objects required in a slab.
1990 */
1991 min_objects = slub_min_objects;
Christoph Lameter9b2cd502008-04-14 19:11:41 +03001992 if (!min_objects)
1993 min_objects = 4 * (fls(nr_cpu_ids) + 1);
Zhang Yanmine8120ff2009-02-12 18:00:17 +02001994 max_objects = (PAGE_SIZE << slub_max_order)/size;
1995 min_objects = min(min_objects, max_objects);
1996
Christoph Lameter5e6d4442007-05-09 02:32:46 -07001997 while (min_objects > 1) {
Christoph Lameterc124f5b2008-04-14 19:13:29 +03001998 fraction = 16;
Christoph Lameter5e6d4442007-05-09 02:32:46 -07001999 while (fraction >= 4) {
2000 order = slab_order(size, min_objects,
2001 slub_max_order, fraction);
2002 if (order <= slub_max_order)
2003 return order;
2004 fraction /= 2;
2005 }
Amerigo Wang5086c389c2009-08-19 21:44:13 +03002006 min_objects--;
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002007 }
2008
2009 /*
2010 * We were unable to place multiple objects in a slab. Now
2011 * lets see if we can place a single object there.
2012 */
2013 order = slab_order(size, 1, slub_max_order, 1);
2014 if (order <= slub_max_order)
2015 return order;
2016
2017 /*
2018 * Doh this slab cannot be placed using slub_max_order.
2019 */
2020 order = slab_order(size, 1, MAX_ORDER, 1);
David Rientjes818cf592009-04-23 09:58:22 +03002021 if (order < MAX_ORDER)
Christoph Lameter5e6d4442007-05-09 02:32:46 -07002022 return order;
2023 return -ENOSYS;
2024}
2025
Christoph Lameter81819f02007-05-06 14:49:36 -07002026/*
Christoph Lameter672bba32007-05-09 02:32:39 -07002027 * Figure out what the alignment of the objects will be.
Christoph Lameter81819f02007-05-06 14:49:36 -07002028 */
2029static unsigned long calculate_alignment(unsigned long flags,
2030 unsigned long align, unsigned long size)
2031{
2032 /*
Christoph Lameter6446faa2008-02-15 23:45:26 -08002033 * If the user wants hardware cache aligned objects then follow that
2034 * suggestion if the object is sufficiently large.
Christoph Lameter81819f02007-05-06 14:49:36 -07002035 *
Christoph Lameter6446faa2008-02-15 23:45:26 -08002036 * The hardware cache alignment cannot override the specified
2037 * alignment though. If that is greater then use it.
Christoph Lameter81819f02007-05-06 14:49:36 -07002038 */
Nick Pigginb6210382008-03-05 14:05:56 -08002039 if (flags & SLAB_HWCACHE_ALIGN) {
2040 unsigned long ralign = cache_line_size();
2041 while (size <= ralign / 2)
2042 ralign /= 2;
2043 align = max(align, ralign);
2044 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002045
2046 if (align < ARCH_SLAB_MINALIGN)
Nick Pigginb6210382008-03-05 14:05:56 -08002047 align = ARCH_SLAB_MINALIGN;
Christoph Lameter81819f02007-05-06 14:49:36 -07002048
2049 return ALIGN(align, sizeof(void *));
2050}
2051
Pekka Enberg5595cff2008-08-05 09:28:47 +03002052static void
2053init_kmem_cache_node(struct kmem_cache_node *n, struct kmem_cache *s)
Christoph Lameter81819f02007-05-06 14:49:36 -07002054{
2055 n->nr_partial = 0;
Christoph Lameter81819f02007-05-06 14:49:36 -07002056 spin_lock_init(&n->list_lock);
2057 INIT_LIST_HEAD(&n->partial);
Christoph Lameter8ab13722007-07-17 04:03:32 -07002058#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter0f389ec2008-04-14 18:53:02 +03002059 atomic_long_set(&n->nr_slabs, 0);
Salman Qazi02b71b72008-09-11 12:25:41 -07002060 atomic_long_set(&n->total_objects, 0);
Christoph Lameter643b1132007-05-06 14:49:42 -07002061 INIT_LIST_HEAD(&n->full);
Christoph Lameter8ab13722007-07-17 04:03:32 -07002062#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07002063}
2064
Christoph Lameter91efd772010-01-21 17:43:35 -06002065static DEFINE_PER_CPU(struct kmem_cache_cpu, kmalloc_percpu[KMALLOC_CACHES]);
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002066
2067static inline int alloc_kmem_cache_cpus(struct kmem_cache *s, gfp_t flags)
2068{
Christoph Lameter756dee72009-12-18 16:26:21 -06002069 if (s < kmalloc_caches + KMALLOC_CACHES && s >= kmalloc_caches)
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002070 /*
2071 * Boot time creation of the kmalloc array. Use static per cpu data
2072 * since the per cpu allocator is not available yet.
2073 */
Stephen Rothwell1154fab2010-03-01 16:04:45 +11002074 s->cpu_slab = kmalloc_percpu + (s - kmalloc_caches);
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002075 else
2076 s->cpu_slab = alloc_percpu(struct kmem_cache_cpu);
2077
2078 if (!s->cpu_slab)
2079 return 0;
2080
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002081 return 1;
2082}
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002083
Christoph Lameter81819f02007-05-06 14:49:36 -07002084#ifdef CONFIG_NUMA
2085/*
2086 * No kmalloc_node yet so do it by hand. We know that this is the first
2087 * slab on the node for this slabcache. There are no concurrent accesses
2088 * possible.
2089 *
2090 * Note that this function only works on the kmalloc_node_cache
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002091 * when allocating for the kmalloc_node_cache. This is used for bootstrapping
2092 * memory on a fresh node that has no slab structures yet.
Christoph Lameter81819f02007-05-06 14:49:36 -07002093 */
David Rientjes0094de92008-11-25 19:14:19 -08002094static void early_kmem_cache_node_alloc(gfp_t gfpflags, int node)
Christoph Lameter81819f02007-05-06 14:49:36 -07002095{
2096 struct page *page;
2097 struct kmem_cache_node *n;
rootba84c732008-01-07 23:20:28 -08002098 unsigned long flags;
Christoph Lameter81819f02007-05-06 14:49:36 -07002099
2100 BUG_ON(kmalloc_caches->size < sizeof(struct kmem_cache_node));
2101
Christoph Lametera2f92ee2007-08-22 14:01:57 -07002102 page = new_slab(kmalloc_caches, gfpflags, node);
Christoph Lameter81819f02007-05-06 14:49:36 -07002103
2104 BUG_ON(!page);
Christoph Lametera2f92ee2007-08-22 14:01:57 -07002105 if (page_to_nid(page) != node) {
2106 printk(KERN_ERR "SLUB: Unable to allocate memory from "
2107 "node %d\n", node);
2108 printk(KERN_ERR "SLUB: Allocating a useless per node structure "
2109 "in order to be able to continue\n");
2110 }
2111
Christoph Lameter81819f02007-05-06 14:49:36 -07002112 n = page->freelist;
2113 BUG_ON(!n);
2114 page->freelist = get_freepointer(kmalloc_caches, n);
2115 page->inuse++;
2116 kmalloc_caches->node[node] = n;
Christoph Lameter8ab13722007-07-17 04:03:32 -07002117#ifdef CONFIG_SLUB_DEBUG
Christoph Lameterd45f39c2007-07-17 04:03:21 -07002118 init_object(kmalloc_caches, n, 1);
2119 init_tracking(kmalloc_caches, n);
Christoph Lameter8ab13722007-07-17 04:03:32 -07002120#endif
Pekka Enberg5595cff2008-08-05 09:28:47 +03002121 init_kmem_cache_node(n, kmalloc_caches);
Christoph Lameter205ab992008-04-14 19:11:40 +03002122 inc_slabs_node(kmalloc_caches, node, page->objects);
Christoph Lameter6446faa2008-02-15 23:45:26 -08002123
rootba84c732008-01-07 23:20:28 -08002124 /*
2125 * lockdep requires consistent irq usage for each lock
2126 * so even though there cannot be a race this early in
2127 * the boot sequence, we still disable irqs.
2128 */
2129 local_irq_save(flags);
Christoph Lameter7c2e1322008-01-07 23:20:27 -08002130 add_partial(n, page, 0);
rootba84c732008-01-07 23:20:28 -08002131 local_irq_restore(flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07002132}
2133
2134static void free_kmem_cache_nodes(struct kmem_cache *s)
2135{
2136 int node;
2137
Christoph Lameterf64dc582007-10-16 01:25:33 -07002138 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002139 struct kmem_cache_node *n = s->node[node];
Alexander Duyck73367bd2010-05-21 14:41:35 -07002140 if (n)
Christoph Lameter81819f02007-05-06 14:49:36 -07002141 kmem_cache_free(kmalloc_caches, n);
2142 s->node[node] = NULL;
2143 }
2144}
2145
2146static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
2147{
2148 int node;
Christoph Lameter81819f02007-05-06 14:49:36 -07002149
Christoph Lameterf64dc582007-10-16 01:25:33 -07002150 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002151 struct kmem_cache_node *n;
2152
Alexander Duyck73367bd2010-05-21 14:41:35 -07002153 if (slab_state == DOWN) {
2154 early_kmem_cache_node_alloc(gfpflags, node);
2155 continue;
Christoph Lameter81819f02007-05-06 14:49:36 -07002156 }
Alexander Duyck73367bd2010-05-21 14:41:35 -07002157 n = kmem_cache_alloc_node(kmalloc_caches,
2158 gfpflags, node);
2159
2160 if (!n) {
2161 free_kmem_cache_nodes(s);
2162 return 0;
2163 }
2164
Christoph Lameter81819f02007-05-06 14:49:36 -07002165 s->node[node] = n;
Pekka Enberg5595cff2008-08-05 09:28:47 +03002166 init_kmem_cache_node(n, s);
Christoph Lameter81819f02007-05-06 14:49:36 -07002167 }
2168 return 1;
2169}
2170#else
2171static void free_kmem_cache_nodes(struct kmem_cache *s)
2172{
2173}
2174
2175static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
2176{
Pekka Enberg5595cff2008-08-05 09:28:47 +03002177 init_kmem_cache_node(&s->local_node, s);
Christoph Lameter81819f02007-05-06 14:49:36 -07002178 return 1;
2179}
2180#endif
2181
David Rientjesc0bdb232009-02-25 09:16:35 +02002182static void set_min_partial(struct kmem_cache *s, unsigned long min)
David Rientjes3b89d7d2009-02-22 17:40:07 -08002183{
2184 if (min < MIN_PARTIAL)
2185 min = MIN_PARTIAL;
2186 else if (min > MAX_PARTIAL)
2187 min = MAX_PARTIAL;
2188 s->min_partial = min;
2189}
2190
Christoph Lameter81819f02007-05-06 14:49:36 -07002191/*
2192 * calculate_sizes() determines the order and the distribution of data within
2193 * a slab object.
2194 */
Christoph Lameter06b285d2008-04-14 19:11:41 +03002195static int calculate_sizes(struct kmem_cache *s, int forced_order)
Christoph Lameter81819f02007-05-06 14:49:36 -07002196{
2197 unsigned long flags = s->flags;
2198 unsigned long size = s->objsize;
2199 unsigned long align = s->align;
Christoph Lameter834f3d12008-04-14 19:11:31 +03002200 int order;
Christoph Lameter81819f02007-05-06 14:49:36 -07002201
2202 /*
Christoph Lameterd8b42bf2008-02-15 23:45:25 -08002203 * Round up object size to the next word boundary. We can only
2204 * place the free pointer at word boundaries and this determines
2205 * the possible location of the free pointer.
2206 */
2207 size = ALIGN(size, sizeof(void *));
2208
2209#ifdef CONFIG_SLUB_DEBUG
2210 /*
Christoph Lameter81819f02007-05-06 14:49:36 -07002211 * Determine if we can poison the object itself. If the user of
2212 * the slab may touch the object after free or before allocation
2213 * then we should never poison the object itself.
2214 */
2215 if ((flags & SLAB_POISON) && !(flags & SLAB_DESTROY_BY_RCU) &&
Christoph Lameterc59def92007-05-16 22:10:50 -07002216 !s->ctor)
Christoph Lameter81819f02007-05-06 14:49:36 -07002217 s->flags |= __OBJECT_POISON;
2218 else
2219 s->flags &= ~__OBJECT_POISON;
2220
Christoph Lameter81819f02007-05-06 14:49:36 -07002221
2222 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07002223 * If we are Redzoning then check if there is some space between the
Christoph Lameter81819f02007-05-06 14:49:36 -07002224 * end of the object and the free pointer. If not then add an
Christoph Lameter672bba32007-05-09 02:32:39 -07002225 * additional word to have some bytes to store Redzone information.
Christoph Lameter81819f02007-05-06 14:49:36 -07002226 */
2227 if ((flags & SLAB_RED_ZONE) && size == s->objsize)
2228 size += sizeof(void *);
Christoph Lameter41ecc552007-05-09 02:32:44 -07002229#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07002230
2231 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07002232 * With that we have determined the number of bytes in actual use
2233 * by the object. This is the potential offset to the free pointer.
Christoph Lameter81819f02007-05-06 14:49:36 -07002234 */
2235 s->inuse = size;
2236
2237 if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) ||
Christoph Lameterc59def92007-05-16 22:10:50 -07002238 s->ctor)) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002239 /*
2240 * Relocate free pointer after the object if it is not
2241 * permitted to overwrite the first word of the object on
2242 * kmem_cache_free.
2243 *
2244 * This is the case if we do RCU, have a constructor or
2245 * destructor or are poisoning the objects.
2246 */
2247 s->offset = size;
2248 size += sizeof(void *);
2249 }
2250
Christoph Lameterc12b3c62007-05-23 13:57:31 -07002251#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter81819f02007-05-06 14:49:36 -07002252 if (flags & SLAB_STORE_USER)
2253 /*
2254 * Need to store information about allocs and frees after
2255 * the object.
2256 */
2257 size += 2 * sizeof(struct track);
2258
Christoph Lameterbe7b3fb2007-05-09 02:32:36 -07002259 if (flags & SLAB_RED_ZONE)
Christoph Lameter81819f02007-05-06 14:49:36 -07002260 /*
2261 * Add some empty padding so that we can catch
2262 * overwrites from earlier objects rather than let
2263 * tracking information or the free pointer be
Frederik Schwarzer0211a9c2008-12-29 22:14:56 +01002264 * corrupted if a user writes before the start
Christoph Lameter81819f02007-05-06 14:49:36 -07002265 * of the object.
2266 */
2267 size += sizeof(void *);
Christoph Lameter41ecc552007-05-09 02:32:44 -07002268#endif
Christoph Lameter672bba32007-05-09 02:32:39 -07002269
Christoph Lameter81819f02007-05-06 14:49:36 -07002270 /*
2271 * Determine the alignment based on various parameters that the
Christoph Lameter65c02d42007-05-09 02:32:35 -07002272 * user specified and the dynamic determination of cache line size
2273 * on bootup.
Christoph Lameter81819f02007-05-06 14:49:36 -07002274 */
2275 align = calculate_alignment(flags, align, s->objsize);
Zhang, Yanmindcb0ce12009-07-30 11:28:11 +08002276 s->align = align;
Christoph Lameter81819f02007-05-06 14:49:36 -07002277
2278 /*
2279 * SLUB stores one object immediately after another beginning from
2280 * offset 0. In order to align the objects we have to simply size
2281 * each object to conform to the alignment.
2282 */
2283 size = ALIGN(size, align);
2284 s->size = size;
Christoph Lameter06b285d2008-04-14 19:11:41 +03002285 if (forced_order >= 0)
2286 order = forced_order;
2287 else
2288 order = calculate_order(size);
Christoph Lameter81819f02007-05-06 14:49:36 -07002289
Christoph Lameter834f3d12008-04-14 19:11:31 +03002290 if (order < 0)
Christoph Lameter81819f02007-05-06 14:49:36 -07002291 return 0;
2292
Christoph Lameterb7a49f02008-02-14 14:21:32 -08002293 s->allocflags = 0;
Christoph Lameter834f3d12008-04-14 19:11:31 +03002294 if (order)
Christoph Lameterb7a49f02008-02-14 14:21:32 -08002295 s->allocflags |= __GFP_COMP;
2296
2297 if (s->flags & SLAB_CACHE_DMA)
2298 s->allocflags |= SLUB_DMA;
2299
2300 if (s->flags & SLAB_RECLAIM_ACCOUNT)
2301 s->allocflags |= __GFP_RECLAIMABLE;
2302
Christoph Lameter81819f02007-05-06 14:49:36 -07002303 /*
2304 * Determine the number of objects per slab
2305 */
Christoph Lameter834f3d12008-04-14 19:11:31 +03002306 s->oo = oo_make(order, size);
Christoph Lameter65c33762008-04-14 19:11:40 +03002307 s->min = oo_make(get_order(size), size);
Christoph Lameter205ab992008-04-14 19:11:40 +03002308 if (oo_objects(s->oo) > oo_objects(s->max))
2309 s->max = s->oo;
Christoph Lameter81819f02007-05-06 14:49:36 -07002310
Christoph Lameter834f3d12008-04-14 19:11:31 +03002311 return !!oo_objects(s->oo);
Christoph Lameter81819f02007-05-06 14:49:36 -07002312
2313}
2314
Christoph Lameter81819f02007-05-06 14:49:36 -07002315static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags,
2316 const char *name, size_t size,
2317 size_t align, unsigned long flags,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07002318 void (*ctor)(void *))
Christoph Lameter81819f02007-05-06 14:49:36 -07002319{
2320 memset(s, 0, kmem_size);
2321 s->name = name;
2322 s->ctor = ctor;
Christoph Lameter81819f02007-05-06 14:49:36 -07002323 s->objsize = size;
Christoph Lameter81819f02007-05-06 14:49:36 -07002324 s->align = align;
Christoph Lameterba0268a2007-09-11 15:24:11 -07002325 s->flags = kmem_cache_flags(size, flags, name, ctor);
Christoph Lameter81819f02007-05-06 14:49:36 -07002326
Christoph Lameter06b285d2008-04-14 19:11:41 +03002327 if (!calculate_sizes(s, -1))
Christoph Lameter81819f02007-05-06 14:49:36 -07002328 goto error;
David Rientjes3de47212009-07-27 18:30:35 -07002329 if (disable_higher_order_debug) {
2330 /*
2331 * Disable debugging flags that store metadata if the min slab
2332 * order increased.
2333 */
2334 if (get_order(s->size) > get_order(s->objsize)) {
2335 s->flags &= ~DEBUG_METADATA_FLAGS;
2336 s->offset = 0;
2337 if (!calculate_sizes(s, -1))
2338 goto error;
2339 }
2340 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002341
David Rientjes3b89d7d2009-02-22 17:40:07 -08002342 /*
2343 * The larger the object size is, the more pages we want on the partial
2344 * list to avoid pounding the page allocator excessively.
2345 */
David Rientjesc0bdb232009-02-25 09:16:35 +02002346 set_min_partial(s, ilog2(s->size));
Christoph Lameter81819f02007-05-06 14:49:36 -07002347 s->refcount = 1;
2348#ifdef CONFIG_NUMA
Christoph Lametere2cb96b2008-08-19 08:51:22 -05002349 s->remote_node_defrag_ratio = 1000;
Christoph Lameter81819f02007-05-06 14:49:36 -07002350#endif
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002351 if (!init_kmem_cache_nodes(s, gfpflags & ~SLUB_DMA))
2352 goto error;
Christoph Lameter81819f02007-05-06 14:49:36 -07002353
Christoph Lameterdfb4f092007-10-16 01:26:05 -07002354 if (alloc_kmem_cache_cpus(s, gfpflags & ~SLUB_DMA))
Christoph Lameter81819f02007-05-06 14:49:36 -07002355 return 1;
Christoph Lameterff120592009-12-18 16:26:22 -06002356
Christoph Lameter4c93c3552007-10-16 01:26:08 -07002357 free_kmem_cache_nodes(s);
Christoph Lameter81819f02007-05-06 14:49:36 -07002358error:
2359 if (flags & SLAB_PANIC)
2360 panic("Cannot create slab %s size=%lu realsize=%u "
2361 "order=%u offset=%u flags=%lx\n",
Christoph Lameter834f3d12008-04-14 19:11:31 +03002362 s->name, (unsigned long)size, s->size, oo_order(s->oo),
Christoph Lameter81819f02007-05-06 14:49:36 -07002363 s->offset, flags);
2364 return 0;
2365}
Christoph Lameter81819f02007-05-06 14:49:36 -07002366
2367/*
2368 * Check if a given pointer is valid
2369 */
2370int kmem_ptr_validate(struct kmem_cache *s, const void *object)
2371{
Pekka Enberg06428782008-01-07 23:20:27 -08002372 struct page *page;
Christoph Lameter81819f02007-05-06 14:49:36 -07002373
Pekka Enbergd3e06e22010-04-07 19:23:41 +03002374 if (!kern_ptr_validate(object, s->size))
2375 return 0;
2376
Christoph Lameter81819f02007-05-06 14:49:36 -07002377 page = get_object_page(object);
2378
2379 if (!page || s != page->slab)
2380 /* No slab or wrong slab */
2381 return 0;
2382
Christoph Lameterabcd08a2007-05-09 02:32:37 -07002383 if (!check_valid_pointer(s, page, object))
Christoph Lameter81819f02007-05-06 14:49:36 -07002384 return 0;
2385
2386 /*
2387 * We could also check if the object is on the slabs freelist.
2388 * But this would be too expensive and it seems that the main
Christoph Lameter6446faa2008-02-15 23:45:26 -08002389 * purpose of kmem_ptr_valid() is to check if the object belongs
Christoph Lameter81819f02007-05-06 14:49:36 -07002390 * to a certain slab.
2391 */
2392 return 1;
2393}
2394EXPORT_SYMBOL(kmem_ptr_validate);
2395
2396/*
2397 * Determine the size of a slab object
2398 */
2399unsigned int kmem_cache_size(struct kmem_cache *s)
2400{
2401 return s->objsize;
2402}
2403EXPORT_SYMBOL(kmem_cache_size);
2404
2405const char *kmem_cache_name(struct kmem_cache *s)
2406{
2407 return s->name;
2408}
2409EXPORT_SYMBOL(kmem_cache_name);
2410
Christoph Lameter33b12c32008-04-25 12:22:43 -07002411static void list_slab_objects(struct kmem_cache *s, struct page *page,
2412 const char *text)
Christoph Lameter81819f02007-05-06 14:49:36 -07002413{
Christoph Lameter33b12c32008-04-25 12:22:43 -07002414#ifdef CONFIG_SLUB_DEBUG
2415 void *addr = page_address(page);
2416 void *p;
Eric Dumazetbbd7d572010-03-24 22:25:47 +01002417 long *map = kzalloc(BITS_TO_LONGS(page->objects) * sizeof(long),
2418 GFP_ATOMIC);
Christoph Lameter33b12c32008-04-25 12:22:43 -07002419
Eric Dumazetbbd7d572010-03-24 22:25:47 +01002420 if (!map)
2421 return;
Christoph Lameter33b12c32008-04-25 12:22:43 -07002422 slab_err(s, page, "%s", text);
2423 slab_lock(page);
2424 for_each_free_object(p, s, page->freelist)
2425 set_bit(slab_index(p, s, addr), map);
2426
2427 for_each_object(p, s, addr, page->objects) {
2428
2429 if (!test_bit(slab_index(p, s, addr), map)) {
2430 printk(KERN_ERR "INFO: Object 0x%p @offset=%tu\n",
2431 p, p - addr);
2432 print_tracking(s, p);
2433 }
2434 }
2435 slab_unlock(page);
Eric Dumazetbbd7d572010-03-24 22:25:47 +01002436 kfree(map);
Christoph Lameter33b12c32008-04-25 12:22:43 -07002437#endif
2438}
2439
Christoph Lameter81819f02007-05-06 14:49:36 -07002440/*
Christoph Lameter599870b2008-04-23 12:36:52 -07002441 * Attempt to free all partial slabs on a node.
Christoph Lameter81819f02007-05-06 14:49:36 -07002442 */
Christoph Lameter599870b2008-04-23 12:36:52 -07002443static void free_partial(struct kmem_cache *s, struct kmem_cache_node *n)
Christoph Lameter81819f02007-05-06 14:49:36 -07002444{
Christoph Lameter81819f02007-05-06 14:49:36 -07002445 unsigned long flags;
2446 struct page *page, *h;
2447
2448 spin_lock_irqsave(&n->list_lock, flags);
Christoph Lameter33b12c32008-04-25 12:22:43 -07002449 list_for_each_entry_safe(page, h, &n->partial, lru) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002450 if (!page->inuse) {
2451 list_del(&page->lru);
2452 discard_slab(s, page);
Christoph Lameter599870b2008-04-23 12:36:52 -07002453 n->nr_partial--;
Christoph Lameter33b12c32008-04-25 12:22:43 -07002454 } else {
2455 list_slab_objects(s, page,
2456 "Objects remaining on kmem_cache_close()");
Christoph Lameter599870b2008-04-23 12:36:52 -07002457 }
Christoph Lameter33b12c32008-04-25 12:22:43 -07002458 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002459 spin_unlock_irqrestore(&n->list_lock, flags);
Christoph Lameter81819f02007-05-06 14:49:36 -07002460}
2461
2462/*
Christoph Lameter672bba32007-05-09 02:32:39 -07002463 * Release all resources used by a slab cache.
Christoph Lameter81819f02007-05-06 14:49:36 -07002464 */
Christoph Lameter0c710012007-07-17 04:03:24 -07002465static inline int kmem_cache_close(struct kmem_cache *s)
Christoph Lameter81819f02007-05-06 14:49:36 -07002466{
2467 int node;
2468
2469 flush_all(s);
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002470 free_percpu(s->cpu_slab);
Christoph Lameter81819f02007-05-06 14:49:36 -07002471 /* Attempt to free all objects */
Christoph Lameterf64dc582007-10-16 01:25:33 -07002472 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter81819f02007-05-06 14:49:36 -07002473 struct kmem_cache_node *n = get_node(s, node);
2474
Christoph Lameter599870b2008-04-23 12:36:52 -07002475 free_partial(s, n);
2476 if (n->nr_partial || slabs_node(s, node))
Christoph Lameter81819f02007-05-06 14:49:36 -07002477 return 1;
2478 }
2479 free_kmem_cache_nodes(s);
2480 return 0;
2481}
2482
2483/*
2484 * Close a cache and release the kmem_cache structure
2485 * (must be used for caches created using kmem_cache_create)
2486 */
2487void kmem_cache_destroy(struct kmem_cache *s)
2488{
2489 down_write(&slub_lock);
2490 s->refcount--;
2491 if (!s->refcount) {
2492 list_del(&s->list);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07002493 up_write(&slub_lock);
Pekka Enbergd629d812008-04-23 22:31:08 +03002494 if (kmem_cache_close(s)) {
2495 printk(KERN_ERR "SLUB %s: %s called for cache that "
2496 "still has objects.\n", s->name, __func__);
2497 dump_stack();
2498 }
Eric Dumazetd76b1592009-09-03 22:38:59 +03002499 if (s->flags & SLAB_DESTROY_BY_RCU)
2500 rcu_barrier();
Christoph Lameter81819f02007-05-06 14:49:36 -07002501 sysfs_slab_remove(s);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07002502 } else
2503 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07002504}
2505EXPORT_SYMBOL(kmem_cache_destroy);
2506
2507/********************************************************************
2508 * Kmalloc subsystem
2509 *******************************************************************/
2510
Christoph Lameter756dee72009-12-18 16:26:21 -06002511struct kmem_cache kmalloc_caches[KMALLOC_CACHES] __cacheline_aligned;
Christoph Lameter81819f02007-05-06 14:49:36 -07002512EXPORT_SYMBOL(kmalloc_caches);
2513
Christoph Lameter81819f02007-05-06 14:49:36 -07002514static int __init setup_slub_min_order(char *str)
2515{
Pekka Enberg06428782008-01-07 23:20:27 -08002516 get_option(&str, &slub_min_order);
Christoph Lameter81819f02007-05-06 14:49:36 -07002517
2518 return 1;
2519}
2520
2521__setup("slub_min_order=", setup_slub_min_order);
2522
2523static int __init setup_slub_max_order(char *str)
2524{
Pekka Enberg06428782008-01-07 23:20:27 -08002525 get_option(&str, &slub_max_order);
David Rientjes818cf592009-04-23 09:58:22 +03002526 slub_max_order = min(slub_max_order, MAX_ORDER - 1);
Christoph Lameter81819f02007-05-06 14:49:36 -07002527
2528 return 1;
2529}
2530
2531__setup("slub_max_order=", setup_slub_max_order);
2532
2533static int __init setup_slub_min_objects(char *str)
2534{
Pekka Enberg06428782008-01-07 23:20:27 -08002535 get_option(&str, &slub_min_objects);
Christoph Lameter81819f02007-05-06 14:49:36 -07002536
2537 return 1;
2538}
2539
2540__setup("slub_min_objects=", setup_slub_min_objects);
2541
2542static int __init setup_slub_nomerge(char *str)
2543{
2544 slub_nomerge = 1;
2545 return 1;
2546}
2547
2548__setup("slub_nomerge", setup_slub_nomerge);
2549
Christoph Lameter81819f02007-05-06 14:49:36 -07002550static struct kmem_cache *create_kmalloc_cache(struct kmem_cache *s,
2551 const char *name, int size, gfp_t gfp_flags)
2552{
2553 unsigned int flags = 0;
2554
2555 if (gfp_flags & SLUB_DMA)
2556 flags = SLAB_CACHE_DMA;
2557
Pekka Enberg83b519e2009-06-10 19:40:04 +03002558 /*
2559 * This function is called with IRQs disabled during early-boot on
2560 * single CPU so there's no need to take slub_lock here.
2561 */
Christoph Lameter81819f02007-05-06 14:49:36 -07002562 if (!kmem_cache_open(s, gfp_flags, name, size, ARCH_KMALLOC_MINALIGN,
Christoph Lameter319d1e22008-04-14 19:11:41 +03002563 flags, NULL))
Christoph Lameter81819f02007-05-06 14:49:36 -07002564 goto panic;
2565
2566 list_add(&s->list, &slab_caches);
Pekka Enberg83b519e2009-06-10 19:40:04 +03002567
Christoph Lameter81819f02007-05-06 14:49:36 -07002568 if (sysfs_slab_add(s))
2569 goto panic;
2570 return s;
2571
2572panic:
2573 panic("Creation of kmalloc slab %s size=%d failed.\n", name, size);
2574}
2575
Christoph Lameter2e443fd2007-07-17 04:03:24 -07002576#ifdef CONFIG_ZONE_DMA
Christoph Lameterffadd4d2009-02-17 12:05:07 -05002577static struct kmem_cache *kmalloc_caches_dma[SLUB_PAGE_SHIFT];
Christoph Lameter1ceef402007-08-07 15:11:48 -07002578
2579static void sysfs_add_func(struct work_struct *w)
2580{
2581 struct kmem_cache *s;
2582
2583 down_write(&slub_lock);
2584 list_for_each_entry(s, &slab_caches, list) {
2585 if (s->flags & __SYSFS_ADD_DEFERRED) {
2586 s->flags &= ~__SYSFS_ADD_DEFERRED;
2587 sysfs_slab_add(s);
2588 }
2589 }
2590 up_write(&slub_lock);
2591}
2592
2593static DECLARE_WORK(sysfs_add_work, sysfs_add_func);
2594
Christoph Lameter2e443fd2007-07-17 04:03:24 -07002595static noinline struct kmem_cache *dma_kmalloc_cache(int index, gfp_t flags)
2596{
2597 struct kmem_cache *s;
Christoph Lameter2e443fd2007-07-17 04:03:24 -07002598 char *text;
2599 size_t realsize;
Nick Piggin964cf352009-06-15 13:35:10 +03002600 unsigned long slabflags;
Christoph Lameter756dee72009-12-18 16:26:21 -06002601 int i;
Christoph Lameter2e443fd2007-07-17 04:03:24 -07002602
2603 s = kmalloc_caches_dma[index];
2604 if (s)
2605 return s;
2606
2607 /* Dynamically create dma cache */
Christoph Lameter1ceef402007-08-07 15:11:48 -07002608 if (flags & __GFP_WAIT)
2609 down_write(&slub_lock);
2610 else {
2611 if (!down_write_trylock(&slub_lock))
2612 goto out;
2613 }
2614
2615 if (kmalloc_caches_dma[index])
2616 goto unlock_out;
Christoph Lameter2e443fd2007-07-17 04:03:24 -07002617
Christoph Lameter7b55f622007-07-17 04:03:27 -07002618 realsize = kmalloc_caches[index].objsize;
Ingo Molnar3adbefe2008-02-05 17:57:39 -08002619 text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d",
2620 (unsigned int)realsize);
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002621
Christoph Lameter756dee72009-12-18 16:26:21 -06002622 s = NULL;
2623 for (i = 0; i < KMALLOC_CACHES; i++)
2624 if (!kmalloc_caches[i].size)
2625 break;
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06002626
Christoph Lameter756dee72009-12-18 16:26:21 -06002627 BUG_ON(i >= KMALLOC_CACHES);
2628 s = kmalloc_caches + i;
Christoph Lameter1ceef402007-08-07 15:11:48 -07002629
Nick Piggin964cf352009-06-15 13:35:10 +03002630 /*
2631 * Must defer sysfs creation to a workqueue because we don't know
2632 * what context we are called from. Before sysfs comes up, we don't
2633 * need to do anything because our sysfs initcall will start by
2634 * adding all existing slabs to sysfs.
2635 */
Pekka Enberg5caf5c72009-06-17 08:30:54 +03002636 slabflags = SLAB_CACHE_DMA|SLAB_NOTRACK;
Nick Piggin964cf352009-06-15 13:35:10 +03002637 if (slab_state >= SYSFS)
2638 slabflags |= __SYSFS_ADD_DEFERRED;
2639
David Rientjes7738dd92010-01-15 12:49:56 -08002640 if (!text || !kmem_cache_open(s, flags, text,
Nick Piggin964cf352009-06-15 13:35:10 +03002641 realsize, ARCH_KMALLOC_MINALIGN, slabflags, NULL)) {
Christoph Lameter756dee72009-12-18 16:26:21 -06002642 s->size = 0;
Christoph Lameter1ceef402007-08-07 15:11:48 -07002643 kfree(text);
2644 goto unlock_out;
Christoph Lameterdfce8642007-07-17 04:03:25 -07002645 }
Christoph Lameter1ceef402007-08-07 15:11:48 -07002646
2647 list_add(&s->list, &slab_caches);
2648 kmalloc_caches_dma[index] = s;
2649
Nick Piggin964cf352009-06-15 13:35:10 +03002650 if (slab_state >= SYSFS)
2651 schedule_work(&sysfs_add_work);
Christoph Lameter1ceef402007-08-07 15:11:48 -07002652
2653unlock_out:
Christoph Lameterdfce8642007-07-17 04:03:25 -07002654 up_write(&slub_lock);
Christoph Lameter1ceef402007-08-07 15:11:48 -07002655out:
Christoph Lameterdfce8642007-07-17 04:03:25 -07002656 return kmalloc_caches_dma[index];
Christoph Lameter2e443fd2007-07-17 04:03:24 -07002657}
2658#endif
2659
Christoph Lameterf1b26332007-07-17 04:03:26 -07002660/*
2661 * Conversion table for small slabs sizes / 8 to the index in the
2662 * kmalloc array. This is necessary for slabs < 192 since we have non power
2663 * of two cache sizes there. The size of larger slabs can be determined using
2664 * fls.
2665 */
2666static s8 size_index[24] = {
2667 3, /* 8 */
2668 4, /* 16 */
2669 5, /* 24 */
2670 5, /* 32 */
2671 6, /* 40 */
2672 6, /* 48 */
2673 6, /* 56 */
2674 6, /* 64 */
2675 1, /* 72 */
2676 1, /* 80 */
2677 1, /* 88 */
2678 1, /* 96 */
2679 7, /* 104 */
2680 7, /* 112 */
2681 7, /* 120 */
2682 7, /* 128 */
2683 2, /* 136 */
2684 2, /* 144 */
2685 2, /* 152 */
2686 2, /* 160 */
2687 2, /* 168 */
2688 2, /* 176 */
2689 2, /* 184 */
2690 2 /* 192 */
2691};
2692
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03002693static inline int size_index_elem(size_t bytes)
2694{
2695 return (bytes - 1) / 8;
2696}
2697
Christoph Lameter81819f02007-05-06 14:49:36 -07002698static struct kmem_cache *get_slab(size_t size, gfp_t flags)
2699{
Christoph Lameterf1b26332007-07-17 04:03:26 -07002700 int index;
Christoph Lameter81819f02007-05-06 14:49:36 -07002701
Christoph Lameterf1b26332007-07-17 04:03:26 -07002702 if (size <= 192) {
2703 if (!size)
2704 return ZERO_SIZE_PTR;
Christoph Lameter81819f02007-05-06 14:49:36 -07002705
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03002706 index = size_index[size_index_elem(size)];
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002707 } else
Christoph Lameterf1b26332007-07-17 04:03:26 -07002708 index = fls(size - 1);
Christoph Lameter81819f02007-05-06 14:49:36 -07002709
2710#ifdef CONFIG_ZONE_DMA
Christoph Lameterf1b26332007-07-17 04:03:26 -07002711 if (unlikely((flags & SLUB_DMA)))
Christoph Lameter2e443fd2007-07-17 04:03:24 -07002712 return dma_kmalloc_cache(index, flags);
Christoph Lameterf1b26332007-07-17 04:03:26 -07002713
Christoph Lameter81819f02007-05-06 14:49:36 -07002714#endif
2715 return &kmalloc_caches[index];
2716}
2717
2718void *__kmalloc(size_t size, gfp_t flags)
2719{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002720 struct kmem_cache *s;
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002721 void *ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002722
Christoph Lameterffadd4d2009-02-17 12:05:07 -05002723 if (unlikely(size > SLUB_MAX_SIZE))
Pekka Enbergeada35e2008-02-11 22:47:46 +02002724 return kmalloc_large(size, flags);
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002725
2726 s = get_slab(size, flags);
2727
2728 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07002729 return s;
2730
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002731 ret = slab_alloc(s, flags, -1, _RET_IP_);
2732
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02002733 trace_kmalloc(_RET_IP_, ret, size, s->size, flags);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002734
2735 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002736}
2737EXPORT_SYMBOL(__kmalloc);
2738
Christoph Lameterf619cfe2008-03-01 13:56:40 -08002739static void *kmalloc_large_node(size_t size, gfp_t flags, int node)
2740{
Vegard Nossumb1eeab62008-11-25 16:55:53 +01002741 struct page *page;
Catalin Marinase4f7c0b42009-07-07 10:32:59 +01002742 void *ptr = NULL;
Christoph Lameterf619cfe2008-03-01 13:56:40 -08002743
Vegard Nossumb1eeab62008-11-25 16:55:53 +01002744 flags |= __GFP_COMP | __GFP_NOTRACK;
2745 page = alloc_pages_node(node, flags, get_order(size));
Christoph Lameterf619cfe2008-03-01 13:56:40 -08002746 if (page)
Catalin Marinase4f7c0b42009-07-07 10:32:59 +01002747 ptr = page_address(page);
2748
2749 kmemleak_alloc(ptr, size, 1, flags);
2750 return ptr;
Christoph Lameterf619cfe2008-03-01 13:56:40 -08002751}
2752
Christoph Lameter81819f02007-05-06 14:49:36 -07002753#ifdef CONFIG_NUMA
2754void *__kmalloc_node(size_t size, gfp_t flags, int node)
2755{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002756 struct kmem_cache *s;
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002757 void *ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002758
Ingo Molnar057685c2009-02-20 12:15:30 +01002759 if (unlikely(size > SLUB_MAX_SIZE)) {
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002760 ret = kmalloc_large_node(size, flags, node);
2761
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02002762 trace_kmalloc_node(_RET_IP_, ret,
2763 size, PAGE_SIZE << get_order(size),
2764 flags, node);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002765
2766 return ret;
2767 }
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002768
2769 s = get_slab(size, flags);
2770
2771 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07002772 return s;
2773
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002774 ret = slab_alloc(s, flags, node, _RET_IP_);
2775
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02002776 trace_kmalloc_node(_RET_IP_, ret, size, s->size, flags, node);
Eduard - Gabriel Munteanu5b882be2008-08-19 20:43:26 +03002777
2778 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07002779}
2780EXPORT_SYMBOL(__kmalloc_node);
2781#endif
2782
2783size_t ksize(const void *object)
2784{
Christoph Lameter272c1d22007-06-08 13:46:49 -07002785 struct page *page;
Christoph Lameter81819f02007-05-06 14:49:36 -07002786 struct kmem_cache *s;
2787
Christoph Lameteref8b4522007-10-16 01:24:46 -07002788 if (unlikely(object == ZERO_SIZE_PTR))
Christoph Lameter272c1d22007-06-08 13:46:49 -07002789 return 0;
2790
Vegard Nossum294a80a2007-12-04 23:45:30 -08002791 page = virt_to_head_page(object);
Vegard Nossum294a80a2007-12-04 23:45:30 -08002792
Pekka Enberg76994412008-05-22 19:22:25 +03002793 if (unlikely(!PageSlab(page))) {
2794 WARN_ON(!PageCompound(page));
Vegard Nossum294a80a2007-12-04 23:45:30 -08002795 return PAGE_SIZE << compound_order(page);
Pekka Enberg76994412008-05-22 19:22:25 +03002796 }
Christoph Lameter81819f02007-05-06 14:49:36 -07002797 s = page->slab;
Christoph Lameter81819f02007-05-06 14:49:36 -07002798
Christoph Lameterae20bfd2008-02-15 23:45:25 -08002799#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter81819f02007-05-06 14:49:36 -07002800 /*
2801 * Debugging requires use of the padding between object
2802 * and whatever may come after it.
2803 */
2804 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
2805 return s->objsize;
2806
Christoph Lameterae20bfd2008-02-15 23:45:25 -08002807#endif
Christoph Lameter81819f02007-05-06 14:49:36 -07002808 /*
2809 * If we have the need to store the freelist pointer
2810 * back there or track user information then we can
2811 * only use the space before that information.
2812 */
2813 if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER))
2814 return s->inuse;
Christoph Lameter81819f02007-05-06 14:49:36 -07002815 /*
2816 * Else we can use all the padding etc for the allocation
2817 */
2818 return s->size;
2819}
Kirill A. Shutemovb1aabec2009-02-10 15:21:44 +02002820EXPORT_SYMBOL(ksize);
Christoph Lameter81819f02007-05-06 14:49:36 -07002821
2822void kfree(const void *x)
2823{
Christoph Lameter81819f02007-05-06 14:49:36 -07002824 struct page *page;
Christoph Lameter5bb983b2008-02-07 17:47:41 -08002825 void *object = (void *)x;
Christoph Lameter81819f02007-05-06 14:49:36 -07002826
Pekka Enberg2121db72009-03-25 11:05:57 +02002827 trace_kfree(_RET_IP_, x);
2828
Satyam Sharma2408c552007-10-16 01:24:44 -07002829 if (unlikely(ZERO_OR_NULL_PTR(x)))
Christoph Lameter81819f02007-05-06 14:49:36 -07002830 return;
2831
Christoph Lameterb49af682007-05-06 14:49:41 -07002832 page = virt_to_head_page(x);
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002833 if (unlikely(!PageSlab(page))) {
Christoph Lameter09375022008-05-28 10:32:22 -07002834 BUG_ON(!PageCompound(page));
Catalin Marinase4f7c0b42009-07-07 10:32:59 +01002835 kmemleak_free(x);
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07002836 put_page(page);
2837 return;
2838 }
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03002839 slab_free(page->slab, page, object, _RET_IP_);
Christoph Lameter81819f02007-05-06 14:49:36 -07002840}
2841EXPORT_SYMBOL(kfree);
2842
Christoph Lameter2086d262007-05-06 14:49:46 -07002843/*
Christoph Lameter672bba32007-05-09 02:32:39 -07002844 * kmem_cache_shrink removes empty slabs from the partial lists and sorts
2845 * the remaining slabs by the number of items in use. The slabs with the
2846 * most items in use come first. New allocations will then fill those up
2847 * and thus they can be removed from the partial lists.
2848 *
2849 * The slabs with the least items are placed last. This results in them
2850 * being allocated from last increasing the chance that the last objects
2851 * are freed in them.
Christoph Lameter2086d262007-05-06 14:49:46 -07002852 */
2853int kmem_cache_shrink(struct kmem_cache *s)
2854{
2855 int node;
2856 int i;
2857 struct kmem_cache_node *n;
2858 struct page *page;
2859 struct page *t;
Christoph Lameter205ab992008-04-14 19:11:40 +03002860 int objects = oo_objects(s->max);
Christoph Lameter2086d262007-05-06 14:49:46 -07002861 struct list_head *slabs_by_inuse =
Christoph Lameter834f3d12008-04-14 19:11:31 +03002862 kmalloc(sizeof(struct list_head) * objects, GFP_KERNEL);
Christoph Lameter2086d262007-05-06 14:49:46 -07002863 unsigned long flags;
2864
2865 if (!slabs_by_inuse)
2866 return -ENOMEM;
2867
2868 flush_all(s);
Christoph Lameterf64dc582007-10-16 01:25:33 -07002869 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter2086d262007-05-06 14:49:46 -07002870 n = get_node(s, node);
2871
2872 if (!n->nr_partial)
2873 continue;
2874
Christoph Lameter834f3d12008-04-14 19:11:31 +03002875 for (i = 0; i < objects; i++)
Christoph Lameter2086d262007-05-06 14:49:46 -07002876 INIT_LIST_HEAD(slabs_by_inuse + i);
2877
2878 spin_lock_irqsave(&n->list_lock, flags);
2879
2880 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07002881 * Build lists indexed by the items in use in each slab.
Christoph Lameter2086d262007-05-06 14:49:46 -07002882 *
Christoph Lameter672bba32007-05-09 02:32:39 -07002883 * Note that concurrent frees may occur while we hold the
2884 * list_lock. page->inuse here is the upper limit.
Christoph Lameter2086d262007-05-06 14:49:46 -07002885 */
2886 list_for_each_entry_safe(page, t, &n->partial, lru) {
2887 if (!page->inuse && slab_trylock(page)) {
2888 /*
2889 * Must hold slab lock here because slab_free
2890 * may have freed the last object and be
2891 * waiting to release the slab.
2892 */
2893 list_del(&page->lru);
2894 n->nr_partial--;
2895 slab_unlock(page);
2896 discard_slab(s, page);
2897 } else {
Christoph Lameterfcda3d82007-07-30 13:06:46 -07002898 list_move(&page->lru,
2899 slabs_by_inuse + page->inuse);
Christoph Lameter2086d262007-05-06 14:49:46 -07002900 }
2901 }
2902
Christoph Lameter2086d262007-05-06 14:49:46 -07002903 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07002904 * Rebuild the partial list with the slabs filled up most
2905 * first and the least used slabs at the end.
Christoph Lameter2086d262007-05-06 14:49:46 -07002906 */
Christoph Lameter834f3d12008-04-14 19:11:31 +03002907 for (i = objects - 1; i >= 0; i--)
Christoph Lameter2086d262007-05-06 14:49:46 -07002908 list_splice(slabs_by_inuse + i, n->partial.prev);
2909
Christoph Lameter2086d262007-05-06 14:49:46 -07002910 spin_unlock_irqrestore(&n->list_lock, flags);
2911 }
2912
2913 kfree(slabs_by_inuse);
2914 return 0;
2915}
2916EXPORT_SYMBOL(kmem_cache_shrink);
2917
Yasunori Gotob9049e22007-10-21 16:41:37 -07002918#if defined(CONFIG_NUMA) && defined(CONFIG_MEMORY_HOTPLUG)
2919static int slab_mem_going_offline_callback(void *arg)
2920{
2921 struct kmem_cache *s;
2922
2923 down_read(&slub_lock);
2924 list_for_each_entry(s, &slab_caches, list)
2925 kmem_cache_shrink(s);
2926 up_read(&slub_lock);
2927
2928 return 0;
2929}
2930
2931static void slab_mem_offline_callback(void *arg)
2932{
2933 struct kmem_cache_node *n;
2934 struct kmem_cache *s;
2935 struct memory_notify *marg = arg;
2936 int offline_node;
2937
2938 offline_node = marg->status_change_nid;
2939
2940 /*
2941 * If the node still has available memory. we need kmem_cache_node
2942 * for it yet.
2943 */
2944 if (offline_node < 0)
2945 return;
2946
2947 down_read(&slub_lock);
2948 list_for_each_entry(s, &slab_caches, list) {
2949 n = get_node(s, offline_node);
2950 if (n) {
2951 /*
2952 * if n->nr_slabs > 0, slabs still exist on the node
2953 * that is going down. We were unable to free them,
Adam Buchbinderc9404c92009-12-18 15:40:42 -05002954 * and offline_pages() function shouldn't call this
Yasunori Gotob9049e22007-10-21 16:41:37 -07002955 * callback. So, we must fail.
2956 */
Christoph Lameter0f389ec2008-04-14 18:53:02 +03002957 BUG_ON(slabs_node(s, offline_node));
Yasunori Gotob9049e22007-10-21 16:41:37 -07002958
2959 s->node[offline_node] = NULL;
2960 kmem_cache_free(kmalloc_caches, n);
2961 }
2962 }
2963 up_read(&slub_lock);
2964}
2965
2966static int slab_mem_going_online_callback(void *arg)
2967{
2968 struct kmem_cache_node *n;
2969 struct kmem_cache *s;
2970 struct memory_notify *marg = arg;
2971 int nid = marg->status_change_nid;
2972 int ret = 0;
2973
2974 /*
2975 * If the node's memory is already available, then kmem_cache_node is
2976 * already created. Nothing to do.
2977 */
2978 if (nid < 0)
2979 return 0;
2980
2981 /*
Christoph Lameter0121c6192008-04-29 16:11:12 -07002982 * We are bringing a node online. No memory is available yet. We must
Yasunori Gotob9049e22007-10-21 16:41:37 -07002983 * allocate a kmem_cache_node structure in order to bring the node
2984 * online.
2985 */
2986 down_read(&slub_lock);
2987 list_for_each_entry(s, &slab_caches, list) {
2988 /*
2989 * XXX: kmem_cache_alloc_node will fallback to other nodes
2990 * since memory is not yet available from the node that
2991 * is brought up.
2992 */
2993 n = kmem_cache_alloc(kmalloc_caches, GFP_KERNEL);
2994 if (!n) {
2995 ret = -ENOMEM;
2996 goto out;
2997 }
Pekka Enberg5595cff2008-08-05 09:28:47 +03002998 init_kmem_cache_node(n, s);
Yasunori Gotob9049e22007-10-21 16:41:37 -07002999 s->node[nid] = n;
3000 }
3001out:
3002 up_read(&slub_lock);
3003 return ret;
3004}
3005
3006static int slab_memory_callback(struct notifier_block *self,
3007 unsigned long action, void *arg)
3008{
3009 int ret = 0;
3010
3011 switch (action) {
3012 case MEM_GOING_ONLINE:
3013 ret = slab_mem_going_online_callback(arg);
3014 break;
3015 case MEM_GOING_OFFLINE:
3016 ret = slab_mem_going_offline_callback(arg);
3017 break;
3018 case MEM_OFFLINE:
3019 case MEM_CANCEL_ONLINE:
3020 slab_mem_offline_callback(arg);
3021 break;
3022 case MEM_ONLINE:
3023 case MEM_CANCEL_OFFLINE:
3024 break;
3025 }
KAMEZAWA Hiroyukidc19f9d2008-12-01 13:13:48 -08003026 if (ret)
3027 ret = notifier_from_errno(ret);
3028 else
3029 ret = NOTIFY_OK;
Yasunori Gotob9049e22007-10-21 16:41:37 -07003030 return ret;
3031}
3032
3033#endif /* CONFIG_MEMORY_HOTPLUG */
3034
Christoph Lameter81819f02007-05-06 14:49:36 -07003035/********************************************************************
3036 * Basic setup of slabs
3037 *******************************************************************/
3038
3039void __init kmem_cache_init(void)
3040{
3041 int i;
Christoph Lameter4b356be2007-06-16 10:16:13 -07003042 int caches = 0;
Christoph Lameter81819f02007-05-06 14:49:36 -07003043
3044#ifdef CONFIG_NUMA
3045 /*
3046 * Must first have the slab cache available for the allocations of the
Christoph Lameter672bba32007-05-09 02:32:39 -07003047 * struct kmem_cache_node's. There is special bootstrap code in
Christoph Lameter81819f02007-05-06 14:49:36 -07003048 * kmem_cache_open for slab_state == DOWN.
3049 */
3050 create_kmalloc_cache(&kmalloc_caches[0], "kmem_cache_node",
Pekka Enberg83b519e2009-06-10 19:40:04 +03003051 sizeof(struct kmem_cache_node), GFP_NOWAIT);
Christoph Lameter8ffa6872007-05-31 00:40:51 -07003052 kmalloc_caches[0].refcount = -1;
Christoph Lameter4b356be2007-06-16 10:16:13 -07003053 caches++;
Yasunori Gotob9049e22007-10-21 16:41:37 -07003054
Nadia Derbey0c40ba42008-04-29 01:00:41 -07003055 hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI);
Christoph Lameter81819f02007-05-06 14:49:36 -07003056#endif
3057
3058 /* Able to allocate the per node structures */
3059 slab_state = PARTIAL;
3060
3061 /* Caches that are not of the two-to-the-power-of size */
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003062 if (KMALLOC_MIN_SIZE <= 32) {
Christoph Lameter4b356be2007-06-16 10:16:13 -07003063 create_kmalloc_cache(&kmalloc_caches[1],
Pekka Enberg83b519e2009-06-10 19:40:04 +03003064 "kmalloc-96", 96, GFP_NOWAIT);
Christoph Lameter4b356be2007-06-16 10:16:13 -07003065 caches++;
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003066 }
3067 if (KMALLOC_MIN_SIZE <= 64) {
Christoph Lameter4b356be2007-06-16 10:16:13 -07003068 create_kmalloc_cache(&kmalloc_caches[2],
Pekka Enberg83b519e2009-06-10 19:40:04 +03003069 "kmalloc-192", 192, GFP_NOWAIT);
Christoph Lameter4b356be2007-06-16 10:16:13 -07003070 caches++;
3071 }
Christoph Lameter81819f02007-05-06 14:49:36 -07003072
Christoph Lameterffadd4d2009-02-17 12:05:07 -05003073 for (i = KMALLOC_SHIFT_LOW; i < SLUB_PAGE_SHIFT; i++) {
Christoph Lameter81819f02007-05-06 14:49:36 -07003074 create_kmalloc_cache(&kmalloc_caches[i],
Pekka Enberg83b519e2009-06-10 19:40:04 +03003075 "kmalloc", 1 << i, GFP_NOWAIT);
Christoph Lameter4b356be2007-06-16 10:16:13 -07003076 caches++;
3077 }
Christoph Lameter81819f02007-05-06 14:49:36 -07003078
Christoph Lameterf1b26332007-07-17 04:03:26 -07003079
3080 /*
3081 * Patch up the size_index table if we have strange large alignment
3082 * requirements for the kmalloc array. This is only the case for
Christoph Lameter6446faa2008-02-15 23:45:26 -08003083 * MIPS it seems. The standard arches will not generate any code here.
Christoph Lameterf1b26332007-07-17 04:03:26 -07003084 *
3085 * Largest permitted alignment is 256 bytes due to the way we
3086 * handle the index determination for the smaller caches.
3087 *
3088 * Make sure that nothing crazy happens if someone starts tinkering
3089 * around with ARCH_KMALLOC_MINALIGN
3090 */
3091 BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 ||
3092 (KMALLOC_MIN_SIZE & (KMALLOC_MIN_SIZE - 1)));
3093
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003094 for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) {
3095 int elem = size_index_elem(i);
3096 if (elem >= ARRAY_SIZE(size_index))
3097 break;
3098 size_index[elem] = KMALLOC_SHIFT_LOW;
3099 }
Christoph Lameterf1b26332007-07-17 04:03:26 -07003100
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003101 if (KMALLOC_MIN_SIZE == 64) {
3102 /*
3103 * The 96 byte size cache is not used if the alignment
3104 * is 64 byte.
3105 */
3106 for (i = 64 + 8; i <= 96; i += 8)
3107 size_index[size_index_elem(i)] = 7;
3108 } else if (KMALLOC_MIN_SIZE == 128) {
Christoph Lameter41d54d32008-07-03 09:14:26 -05003109 /*
3110 * The 192 byte sized cache is not used if the alignment
3111 * is 128 byte. Redirect kmalloc to use the 256 byte cache
3112 * instead.
3113 */
3114 for (i = 128 + 8; i <= 192; i += 8)
Aaro Koskinenacdfcd02009-08-28 14:28:54 +03003115 size_index[size_index_elem(i)] = 8;
Christoph Lameter41d54d32008-07-03 09:14:26 -05003116 }
3117
Christoph Lameter81819f02007-05-06 14:49:36 -07003118 slab_state = UP;
3119
3120 /* Provide the correct kmalloc names now that the caches are up */
Christoph Lameterffadd4d2009-02-17 12:05:07 -05003121 for (i = KMALLOC_SHIFT_LOW; i < SLUB_PAGE_SHIFT; i++)
Christoph Lameter81819f02007-05-06 14:49:36 -07003122 kmalloc_caches[i]. name =
Pekka Enberg83b519e2009-06-10 19:40:04 +03003123 kasprintf(GFP_NOWAIT, "kmalloc-%d", 1 << i);
Christoph Lameter81819f02007-05-06 14:49:36 -07003124
3125#ifdef CONFIG_SMP
3126 register_cpu_notifier(&slab_notifier);
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06003127#endif
3128#ifdef CONFIG_NUMA
3129 kmem_size = offsetof(struct kmem_cache, node) +
3130 nr_node_ids * sizeof(struct kmem_cache_node *);
Christoph Lameter4c93c3552007-10-16 01:26:08 -07003131#else
3132 kmem_size = sizeof(struct kmem_cache);
Christoph Lameter81819f02007-05-06 14:49:36 -07003133#endif
3134
Ingo Molnar3adbefe2008-02-05 17:57:39 -08003135 printk(KERN_INFO
3136 "SLUB: Genslabs=%d, HWalign=%d, Order=%d-%d, MinObjects=%d,"
Christoph Lameter4b356be2007-06-16 10:16:13 -07003137 " CPUs=%d, Nodes=%d\n",
3138 caches, cache_line_size(),
Christoph Lameter81819f02007-05-06 14:49:36 -07003139 slub_min_order, slub_max_order, slub_min_objects,
3140 nr_cpu_ids, nr_node_ids);
3141}
3142
Pekka Enberg7e85ee02009-06-12 14:03:06 +03003143void __init kmem_cache_init_late(void)
3144{
Pekka Enberg7e85ee02009-06-12 14:03:06 +03003145}
3146
Christoph Lameter81819f02007-05-06 14:49:36 -07003147/*
3148 * Find a mergeable slab cache
3149 */
3150static int slab_unmergeable(struct kmem_cache *s)
3151{
3152 if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE))
3153 return 1;
3154
Christoph Lameterc59def92007-05-16 22:10:50 -07003155 if (s->ctor)
Christoph Lameter81819f02007-05-06 14:49:36 -07003156 return 1;
3157
Christoph Lameter8ffa6872007-05-31 00:40:51 -07003158 /*
3159 * We may have set a slab to be unmergeable during bootstrap.
3160 */
3161 if (s->refcount < 0)
3162 return 1;
3163
Christoph Lameter81819f02007-05-06 14:49:36 -07003164 return 0;
3165}
3166
3167static struct kmem_cache *find_mergeable(size_t size,
Christoph Lameterba0268a2007-09-11 15:24:11 -07003168 size_t align, unsigned long flags, const char *name,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07003169 void (*ctor)(void *))
Christoph Lameter81819f02007-05-06 14:49:36 -07003170{
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07003171 struct kmem_cache *s;
Christoph Lameter81819f02007-05-06 14:49:36 -07003172
3173 if (slub_nomerge || (flags & SLUB_NEVER_MERGE))
3174 return NULL;
3175
Christoph Lameterc59def92007-05-16 22:10:50 -07003176 if (ctor)
Christoph Lameter81819f02007-05-06 14:49:36 -07003177 return NULL;
3178
3179 size = ALIGN(size, sizeof(void *));
3180 align = calculate_alignment(flags, align, size);
3181 size = ALIGN(size, align);
Christoph Lameterba0268a2007-09-11 15:24:11 -07003182 flags = kmem_cache_flags(size, flags, name, NULL);
Christoph Lameter81819f02007-05-06 14:49:36 -07003183
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07003184 list_for_each_entry(s, &slab_caches, list) {
Christoph Lameter81819f02007-05-06 14:49:36 -07003185 if (slab_unmergeable(s))
3186 continue;
3187
3188 if (size > s->size)
3189 continue;
3190
Christoph Lameterba0268a2007-09-11 15:24:11 -07003191 if ((flags & SLUB_MERGE_SAME) != (s->flags & SLUB_MERGE_SAME))
Christoph Lameter81819f02007-05-06 14:49:36 -07003192 continue;
3193 /*
3194 * Check if alignment is compatible.
3195 * Courtesy of Adrian Drzewiecki
3196 */
Pekka Enberg06428782008-01-07 23:20:27 -08003197 if ((s->size & ~(align - 1)) != s->size)
Christoph Lameter81819f02007-05-06 14:49:36 -07003198 continue;
3199
3200 if (s->size - size >= sizeof(void *))
3201 continue;
3202
3203 return s;
3204 }
3205 return NULL;
3206}
3207
3208struct kmem_cache *kmem_cache_create(const char *name, size_t size,
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07003209 size_t align, unsigned long flags, void (*ctor)(void *))
Christoph Lameter81819f02007-05-06 14:49:36 -07003210{
3211 struct kmem_cache *s;
3212
Benjamin Herrenschmidtfe1ff492009-09-21 17:02:30 -07003213 if (WARN_ON(!name))
3214 return NULL;
3215
Christoph Lameter81819f02007-05-06 14:49:36 -07003216 down_write(&slub_lock);
Christoph Lameterba0268a2007-09-11 15:24:11 -07003217 s = find_mergeable(size, align, flags, name, ctor);
Christoph Lameter81819f02007-05-06 14:49:36 -07003218 if (s) {
3219 s->refcount++;
3220 /*
3221 * Adjust the object sizes so that we clear
3222 * the complete object on kzalloc.
3223 */
3224 s->objsize = max(s->objsize, (int)size);
3225 s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *)));
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003226 up_write(&slub_lock);
Christoph Lameter6446faa2008-02-15 23:45:26 -08003227
David Rientjes7b8f3b62008-12-17 22:09:46 -08003228 if (sysfs_slab_alias(s, name)) {
3229 down_write(&slub_lock);
3230 s->refcount--;
3231 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07003232 goto err;
David Rientjes7b8f3b62008-12-17 22:09:46 -08003233 }
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003234 return s;
3235 }
Christoph Lameter6446faa2008-02-15 23:45:26 -08003236
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003237 s = kmalloc(kmem_size, GFP_KERNEL);
3238 if (s) {
3239 if (kmem_cache_open(s, GFP_KERNEL, name,
Christoph Lameterc59def92007-05-16 22:10:50 -07003240 size, align, flags, ctor)) {
Christoph Lameter81819f02007-05-06 14:49:36 -07003241 list_add(&s->list, &slab_caches);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003242 up_write(&slub_lock);
David Rientjes7b8f3b62008-12-17 22:09:46 -08003243 if (sysfs_slab_add(s)) {
3244 down_write(&slub_lock);
3245 list_del(&s->list);
3246 up_write(&slub_lock);
3247 kfree(s);
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003248 goto err;
David Rientjes7b8f3b62008-12-17 22:09:46 -08003249 }
Christoph Lametera0e1d1b2007-07-17 04:03:31 -07003250 return s;
3251 }
3252 kfree(s);
Christoph Lameter81819f02007-05-06 14:49:36 -07003253 }
3254 up_write(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07003255
3256err:
Christoph Lameter81819f02007-05-06 14:49:36 -07003257 if (flags & SLAB_PANIC)
3258 panic("Cannot create slabcache %s\n", name);
3259 else
3260 s = NULL;
3261 return s;
3262}
3263EXPORT_SYMBOL(kmem_cache_create);
3264
Christoph Lameter81819f02007-05-06 14:49:36 -07003265#ifdef CONFIG_SMP
Christoph Lameter27390bc2007-06-01 00:47:09 -07003266/*
Christoph Lameter672bba32007-05-09 02:32:39 -07003267 * Use the cpu notifier to insure that the cpu slabs are flushed when
3268 * necessary.
Christoph Lameter81819f02007-05-06 14:49:36 -07003269 */
3270static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
3271 unsigned long action, void *hcpu)
3272{
3273 long cpu = (long)hcpu;
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07003274 struct kmem_cache *s;
3275 unsigned long flags;
Christoph Lameter81819f02007-05-06 14:49:36 -07003276
3277 switch (action) {
3278 case CPU_UP_CANCELED:
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07003279 case CPU_UP_CANCELED_FROZEN:
Christoph Lameter81819f02007-05-06 14:49:36 -07003280 case CPU_DEAD:
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07003281 case CPU_DEAD_FROZEN:
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07003282 down_read(&slub_lock);
3283 list_for_each_entry(s, &slab_caches, list) {
3284 local_irq_save(flags);
3285 __flush_cpu_slab(s, cpu);
3286 local_irq_restore(flags);
3287 }
3288 up_read(&slub_lock);
Christoph Lameter81819f02007-05-06 14:49:36 -07003289 break;
3290 default:
3291 break;
3292 }
3293 return NOTIFY_OK;
3294}
3295
Pekka Enberg06428782008-01-07 23:20:27 -08003296static struct notifier_block __cpuinitdata slab_notifier = {
Ingo Molnar3adbefe2008-02-05 17:57:39 -08003297 .notifier_call = slab_cpuup_callback
Pekka Enberg06428782008-01-07 23:20:27 -08003298};
Christoph Lameter81819f02007-05-06 14:49:36 -07003299
3300#endif
3301
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03003302void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, unsigned long caller)
Christoph Lameter81819f02007-05-06 14:49:36 -07003303{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003304 struct kmem_cache *s;
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003305 void *ret;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003306
Christoph Lameterffadd4d2009-02-17 12:05:07 -05003307 if (unlikely(size > SLUB_MAX_SIZE))
Pekka Enbergeada35e2008-02-11 22:47:46 +02003308 return kmalloc_large(size, gfpflags);
3309
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003310 s = get_slab(size, gfpflags);
Christoph Lameter81819f02007-05-06 14:49:36 -07003311
Satyam Sharma2408c552007-10-16 01:24:44 -07003312 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07003313 return s;
Christoph Lameter81819f02007-05-06 14:49:36 -07003314
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003315 ret = slab_alloc(s, gfpflags, -1, caller);
3316
3317 /* Honor the call site pointer we recieved. */
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02003318 trace_kmalloc(caller, ret, size, s->size, gfpflags);
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003319
3320 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07003321}
3322
3323void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03003324 int node, unsigned long caller)
Christoph Lameter81819f02007-05-06 14:49:36 -07003325{
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003326 struct kmem_cache *s;
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003327 void *ret;
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003328
Xiaotian Fengd3e14aa2010-04-08 17:26:44 +08003329 if (unlikely(size > SLUB_MAX_SIZE)) {
3330 ret = kmalloc_large_node(size, gfpflags, node);
3331
3332 trace_kmalloc_node(caller, ret,
3333 size, PAGE_SIZE << get_order(size),
3334 gfpflags, node);
3335
3336 return ret;
3337 }
Pekka Enbergeada35e2008-02-11 22:47:46 +02003338
Christoph Lameteraadb4bc2007-10-16 01:24:38 -07003339 s = get_slab(size, gfpflags);
Christoph Lameter81819f02007-05-06 14:49:36 -07003340
Satyam Sharma2408c552007-10-16 01:24:44 -07003341 if (unlikely(ZERO_OR_NULL_PTR(s)))
Christoph Lameter6cb8f912007-07-17 04:03:22 -07003342 return s;
Christoph Lameter81819f02007-05-06 14:49:36 -07003343
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003344 ret = slab_alloc(s, gfpflags, node, caller);
3345
3346 /* Honor the call site pointer we recieved. */
Eduard - Gabriel Munteanuca2b84cb2009-03-23 15:12:24 +02003347 trace_kmalloc_node(caller, ret, size, s->size, gfpflags, node);
Eduard - Gabriel Munteanu94b528d2008-08-24 20:49:35 +03003348
3349 return ret;
Christoph Lameter81819f02007-05-06 14:49:36 -07003350}
3351
Christoph Lameterf6acb632008-04-29 16:16:06 -07003352#ifdef CONFIG_SLUB_DEBUG
Christoph Lameter205ab992008-04-14 19:11:40 +03003353static int count_inuse(struct page *page)
3354{
3355 return page->inuse;
3356}
3357
3358static int count_total(struct page *page)
3359{
3360 return page->objects;
3361}
3362
Christoph Lameter434e2452007-07-17 04:03:30 -07003363static int validate_slab(struct kmem_cache *s, struct page *page,
3364 unsigned long *map)
Christoph Lameter53e15af2007-05-06 14:49:43 -07003365{
3366 void *p;
Christoph Lametera973e9d2008-03-01 13:40:44 -08003367 void *addr = page_address(page);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003368
3369 if (!check_slab(s, page) ||
3370 !on_freelist(s, page, NULL))
3371 return 0;
3372
3373 /* Now we know that a valid freelist exists */
Christoph Lameter39b26462008-04-14 19:11:30 +03003374 bitmap_zero(map, page->objects);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003375
Christoph Lameter7656c722007-05-09 02:32:40 -07003376 for_each_free_object(p, s, page->freelist) {
3377 set_bit(slab_index(p, s, addr), map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003378 if (!check_object(s, page, p, 0))
3379 return 0;
3380 }
3381
Christoph Lameter224a88b2008-04-14 19:11:31 +03003382 for_each_object(p, s, addr, page->objects)
Christoph Lameter7656c722007-05-09 02:32:40 -07003383 if (!test_bit(slab_index(p, s, addr), map))
Christoph Lameter53e15af2007-05-06 14:49:43 -07003384 if (!check_object(s, page, p, 1))
3385 return 0;
3386 return 1;
3387}
3388
Christoph Lameter434e2452007-07-17 04:03:30 -07003389static void validate_slab_slab(struct kmem_cache *s, struct page *page,
3390 unsigned long *map)
Christoph Lameter53e15af2007-05-06 14:49:43 -07003391{
3392 if (slab_trylock(page)) {
Christoph Lameter434e2452007-07-17 04:03:30 -07003393 validate_slab(s, page, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003394 slab_unlock(page);
3395 } else
3396 printk(KERN_INFO "SLUB %s: Skipped busy slab 0x%p\n",
3397 s->name, page);
3398
3399 if (s->flags & DEBUG_DEFAULT_FLAGS) {
Andy Whitcroft8a380822008-07-23 21:27:18 -07003400 if (!PageSlubDebug(page))
3401 printk(KERN_ERR "SLUB %s: SlubDebug not set "
Christoph Lameter53e15af2007-05-06 14:49:43 -07003402 "on slab 0x%p\n", s->name, page);
3403 } else {
Andy Whitcroft8a380822008-07-23 21:27:18 -07003404 if (PageSlubDebug(page))
3405 printk(KERN_ERR "SLUB %s: SlubDebug set on "
Christoph Lameter53e15af2007-05-06 14:49:43 -07003406 "slab 0x%p\n", s->name, page);
3407 }
3408}
3409
Christoph Lameter434e2452007-07-17 04:03:30 -07003410static int validate_slab_node(struct kmem_cache *s,
3411 struct kmem_cache_node *n, unsigned long *map)
Christoph Lameter53e15af2007-05-06 14:49:43 -07003412{
3413 unsigned long count = 0;
3414 struct page *page;
3415 unsigned long flags;
3416
3417 spin_lock_irqsave(&n->list_lock, flags);
3418
3419 list_for_each_entry(page, &n->partial, lru) {
Christoph Lameter434e2452007-07-17 04:03:30 -07003420 validate_slab_slab(s, page, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003421 count++;
3422 }
3423 if (count != n->nr_partial)
3424 printk(KERN_ERR "SLUB %s: %ld partial slabs counted but "
3425 "counter=%ld\n", s->name, count, n->nr_partial);
3426
3427 if (!(s->flags & SLAB_STORE_USER))
3428 goto out;
3429
3430 list_for_each_entry(page, &n->full, lru) {
Christoph Lameter434e2452007-07-17 04:03:30 -07003431 validate_slab_slab(s, page, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003432 count++;
3433 }
3434 if (count != atomic_long_read(&n->nr_slabs))
3435 printk(KERN_ERR "SLUB: %s %ld slabs counted but "
3436 "counter=%ld\n", s->name, count,
3437 atomic_long_read(&n->nr_slabs));
3438
3439out:
3440 spin_unlock_irqrestore(&n->list_lock, flags);
3441 return count;
3442}
3443
Christoph Lameter434e2452007-07-17 04:03:30 -07003444static long validate_slab_cache(struct kmem_cache *s)
Christoph Lameter53e15af2007-05-06 14:49:43 -07003445{
3446 int node;
3447 unsigned long count = 0;
Christoph Lameter205ab992008-04-14 19:11:40 +03003448 unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
Christoph Lameter434e2452007-07-17 04:03:30 -07003449 sizeof(unsigned long), GFP_KERNEL);
3450
3451 if (!map)
3452 return -ENOMEM;
Christoph Lameter53e15af2007-05-06 14:49:43 -07003453
3454 flush_all(s);
Christoph Lameterf64dc582007-10-16 01:25:33 -07003455 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter53e15af2007-05-06 14:49:43 -07003456 struct kmem_cache_node *n = get_node(s, node);
3457
Christoph Lameter434e2452007-07-17 04:03:30 -07003458 count += validate_slab_node(s, n, map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003459 }
Christoph Lameter434e2452007-07-17 04:03:30 -07003460 kfree(map);
Christoph Lameter53e15af2007-05-06 14:49:43 -07003461 return count;
3462}
3463
Christoph Lameterb3459702007-05-09 02:32:41 -07003464#ifdef SLUB_RESILIENCY_TEST
3465static void resiliency_test(void)
3466{
3467 u8 *p;
3468
3469 printk(KERN_ERR "SLUB resiliency testing\n");
3470 printk(KERN_ERR "-----------------------\n");
3471 printk(KERN_ERR "A. Corruption after allocation\n");
3472
3473 p = kzalloc(16, GFP_KERNEL);
3474 p[16] = 0x12;
3475 printk(KERN_ERR "\n1. kmalloc-16: Clobber Redzone/next pointer"
3476 " 0x12->0x%p\n\n", p + 16);
3477
3478 validate_slab_cache(kmalloc_caches + 4);
3479
3480 /* Hmmm... The next two are dangerous */
3481 p = kzalloc(32, GFP_KERNEL);
3482 p[32 + sizeof(void *)] = 0x34;
3483 printk(KERN_ERR "\n2. kmalloc-32: Clobber next pointer/next slab"
Ingo Molnar3adbefe2008-02-05 17:57:39 -08003484 " 0x34 -> -0x%p\n", p);
3485 printk(KERN_ERR
3486 "If allocated object is overwritten then not detectable\n\n");
Christoph Lameterb3459702007-05-09 02:32:41 -07003487
3488 validate_slab_cache(kmalloc_caches + 5);
3489 p = kzalloc(64, GFP_KERNEL);
3490 p += 64 + (get_cycles() & 0xff) * sizeof(void *);
3491 *p = 0x56;
3492 printk(KERN_ERR "\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n",
3493 p);
Ingo Molnar3adbefe2008-02-05 17:57:39 -08003494 printk(KERN_ERR
3495 "If allocated object is overwritten then not detectable\n\n");
Christoph Lameterb3459702007-05-09 02:32:41 -07003496 validate_slab_cache(kmalloc_caches + 6);
3497
3498 printk(KERN_ERR "\nB. Corruption after free\n");
3499 p = kzalloc(128, GFP_KERNEL);
3500 kfree(p);
3501 *p = 0x78;
3502 printk(KERN_ERR "1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p);
3503 validate_slab_cache(kmalloc_caches + 7);
3504
3505 p = kzalloc(256, GFP_KERNEL);
3506 kfree(p);
3507 p[50] = 0x9a;
Ingo Molnar3adbefe2008-02-05 17:57:39 -08003508 printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n",
3509 p);
Christoph Lameterb3459702007-05-09 02:32:41 -07003510 validate_slab_cache(kmalloc_caches + 8);
3511
3512 p = kzalloc(512, GFP_KERNEL);
3513 kfree(p);
3514 p[512] = 0xab;
3515 printk(KERN_ERR "\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p);
3516 validate_slab_cache(kmalloc_caches + 9);
3517}
3518#else
3519static void resiliency_test(void) {};
3520#endif
3521
Christoph Lameter88a420e2007-05-06 14:49:45 -07003522/*
Christoph Lameter672bba32007-05-09 02:32:39 -07003523 * Generate lists of code addresses where slabcache objects are allocated
Christoph Lameter88a420e2007-05-06 14:49:45 -07003524 * and freed.
3525 */
3526
3527struct location {
3528 unsigned long count;
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03003529 unsigned long addr;
Christoph Lameter45edfa52007-05-09 02:32:45 -07003530 long long sum_time;
3531 long min_time;
3532 long max_time;
3533 long min_pid;
3534 long max_pid;
Rusty Russell174596a2009-01-01 10:12:29 +10303535 DECLARE_BITMAP(cpus, NR_CPUS);
Christoph Lameter45edfa52007-05-09 02:32:45 -07003536 nodemask_t nodes;
Christoph Lameter88a420e2007-05-06 14:49:45 -07003537};
3538
3539struct loc_track {
3540 unsigned long max;
3541 unsigned long count;
3542 struct location *loc;
3543};
3544
3545static void free_loc_track(struct loc_track *t)
3546{
3547 if (t->max)
3548 free_pages((unsigned long)t->loc,
3549 get_order(sizeof(struct location) * t->max));
3550}
3551
Christoph Lameter68dff6a2007-07-17 04:03:20 -07003552static int alloc_loc_track(struct loc_track *t, unsigned long max, gfp_t flags)
Christoph Lameter88a420e2007-05-06 14:49:45 -07003553{
3554 struct location *l;
3555 int order;
3556
Christoph Lameter88a420e2007-05-06 14:49:45 -07003557 order = get_order(sizeof(struct location) * max);
3558
Christoph Lameter68dff6a2007-07-17 04:03:20 -07003559 l = (void *)__get_free_pages(flags, order);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003560 if (!l)
3561 return 0;
3562
3563 if (t->count) {
3564 memcpy(l, t->loc, sizeof(struct location) * t->count);
3565 free_loc_track(t);
3566 }
3567 t->max = max;
3568 t->loc = l;
3569 return 1;
3570}
3571
3572static int add_location(struct loc_track *t, struct kmem_cache *s,
Christoph Lameter45edfa52007-05-09 02:32:45 -07003573 const struct track *track)
Christoph Lameter88a420e2007-05-06 14:49:45 -07003574{
3575 long start, end, pos;
3576 struct location *l;
Eduard - Gabriel Munteanuce71e272008-08-19 20:43:25 +03003577 unsigned long caddr;
Christoph Lameter45edfa52007-05-09 02:32:45 -07003578 unsigned long age = jiffies - track->when;
Christoph Lameter88a420e2007-05-06 14:49:45 -07003579
3580 start = -1;
3581 end = t->count;
3582
3583 for ( ; ; ) {
3584 pos = start + (end - start + 1) / 2;
3585
3586 /*
3587 * There is nothing at "end". If we end up there
3588 * we need to add something to before end.
3589 */
3590 if (pos == end)
3591 break;
3592
3593 caddr = t->loc[pos].addr;
Christoph Lameter45edfa52007-05-09 02:32:45 -07003594 if (track->addr == caddr) {
3595
3596 l = &t->loc[pos];
3597 l->count++;
3598 if (track->when) {
3599 l->sum_time += age;
3600 if (age < l->min_time)
3601 l->min_time = age;
3602 if (age > l->max_time)
3603 l->max_time = age;
3604
3605 if (track->pid < l->min_pid)
3606 l->min_pid = track->pid;
3607 if (track->pid > l->max_pid)
3608 l->max_pid = track->pid;
3609
Rusty Russell174596a2009-01-01 10:12:29 +10303610 cpumask_set_cpu(track->cpu,
3611 to_cpumask(l->cpus));
Christoph Lameter45edfa52007-05-09 02:32:45 -07003612 }
3613 node_set(page_to_nid(virt_to_page(track)), l->nodes);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003614 return 1;
3615 }
3616
Christoph Lameter45edfa52007-05-09 02:32:45 -07003617 if (track->addr < caddr)
Christoph Lameter88a420e2007-05-06 14:49:45 -07003618 end = pos;
3619 else
3620 start = pos;
3621 }
3622
3623 /*
Christoph Lameter672bba32007-05-09 02:32:39 -07003624 * Not found. Insert new tracking element.
Christoph Lameter88a420e2007-05-06 14:49:45 -07003625 */
Christoph Lameter68dff6a2007-07-17 04:03:20 -07003626 if (t->count >= t->max && !alloc_loc_track(t, 2 * t->max, GFP_ATOMIC))
Christoph Lameter88a420e2007-05-06 14:49:45 -07003627 return 0;
3628
3629 l = t->loc + pos;
3630 if (pos < t->count)
3631 memmove(l + 1, l,
3632 (t->count - pos) * sizeof(struct location));
3633 t->count++;
3634 l->count = 1;
Christoph Lameter45edfa52007-05-09 02:32:45 -07003635 l->addr = track->addr;
3636 l->sum_time = age;
3637 l->min_time = age;
3638 l->max_time = age;
3639 l->min_pid = track->pid;
3640 l->max_pid = track->pid;
Rusty Russell174596a2009-01-01 10:12:29 +10303641 cpumask_clear(to_cpumask(l->cpus));
3642 cpumask_set_cpu(track->cpu, to_cpumask(l->cpus));
Christoph Lameter45edfa52007-05-09 02:32:45 -07003643 nodes_clear(l->nodes);
3644 node_set(page_to_nid(virt_to_page(track)), l->nodes);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003645 return 1;
3646}
3647
3648static void process_slab(struct loc_track *t, struct kmem_cache *s,
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003649 struct page *page, enum track_item alloc,
3650 long *map)
Christoph Lameter88a420e2007-05-06 14:49:45 -07003651{
Christoph Lametera973e9d2008-03-01 13:40:44 -08003652 void *addr = page_address(page);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003653 void *p;
3654
Christoph Lameter39b26462008-04-14 19:11:30 +03003655 bitmap_zero(map, page->objects);
Christoph Lameter7656c722007-05-09 02:32:40 -07003656 for_each_free_object(p, s, page->freelist)
3657 set_bit(slab_index(p, s, addr), map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003658
Christoph Lameter224a88b2008-04-14 19:11:31 +03003659 for_each_object(p, s, addr, page->objects)
Christoph Lameter45edfa52007-05-09 02:32:45 -07003660 if (!test_bit(slab_index(p, s, addr), map))
3661 add_location(t, s, get_track(s, p, alloc));
Christoph Lameter88a420e2007-05-06 14:49:45 -07003662}
3663
3664static int list_locations(struct kmem_cache *s, char *buf,
3665 enum track_item alloc)
3666{
Harvey Harrisone374d482008-01-31 15:20:50 -08003667 int len = 0;
Christoph Lameter88a420e2007-05-06 14:49:45 -07003668 unsigned long i;
Christoph Lameter68dff6a2007-07-17 04:03:20 -07003669 struct loc_track t = { 0, 0, NULL };
Christoph Lameter88a420e2007-05-06 14:49:45 -07003670 int node;
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003671 unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
3672 sizeof(unsigned long), GFP_KERNEL);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003673
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003674 if (!map || !alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location),
3675 GFP_TEMPORARY)) {
3676 kfree(map);
Christoph Lameter68dff6a2007-07-17 04:03:20 -07003677 return sprintf(buf, "Out of memory\n");
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003678 }
Christoph Lameter88a420e2007-05-06 14:49:45 -07003679 /* Push back cpu slabs */
3680 flush_all(s);
3681
Christoph Lameterf64dc582007-10-16 01:25:33 -07003682 for_each_node_state(node, N_NORMAL_MEMORY) {
Christoph Lameter88a420e2007-05-06 14:49:45 -07003683 struct kmem_cache_node *n = get_node(s, node);
3684 unsigned long flags;
3685 struct page *page;
3686
Christoph Lameter9e869432007-08-22 14:01:56 -07003687 if (!atomic_long_read(&n->nr_slabs))
Christoph Lameter88a420e2007-05-06 14:49:45 -07003688 continue;
3689
3690 spin_lock_irqsave(&n->list_lock, flags);
3691 list_for_each_entry(page, &n->partial, lru)
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003692 process_slab(&t, s, page, alloc, map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003693 list_for_each_entry(page, &n->full, lru)
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003694 process_slab(&t, s, page, alloc, map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003695 spin_unlock_irqrestore(&n->list_lock, flags);
3696 }
3697
3698 for (i = 0; i < t.count; i++) {
Christoph Lameter45edfa52007-05-09 02:32:45 -07003699 struct location *l = &t.loc[i];
Christoph Lameter88a420e2007-05-06 14:49:45 -07003700
Hugh Dickins9c246242008-12-09 13:14:27 -08003701 if (len > PAGE_SIZE - KSYM_SYMBOL_LEN - 100)
Christoph Lameter88a420e2007-05-06 14:49:45 -07003702 break;
Harvey Harrisone374d482008-01-31 15:20:50 -08003703 len += sprintf(buf + len, "%7ld ", l->count);
Christoph Lameter45edfa52007-05-09 02:32:45 -07003704
3705 if (l->addr)
Harvey Harrisone374d482008-01-31 15:20:50 -08003706 len += sprint_symbol(buf + len, (unsigned long)l->addr);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003707 else
Harvey Harrisone374d482008-01-31 15:20:50 -08003708 len += sprintf(buf + len, "<not-available>");
Christoph Lameter45edfa52007-05-09 02:32:45 -07003709
3710 if (l->sum_time != l->min_time) {
Harvey Harrisone374d482008-01-31 15:20:50 -08003711 len += sprintf(buf + len, " age=%ld/%ld/%ld",
Roman Zippelf8bd2252008-05-01 04:34:31 -07003712 l->min_time,
3713 (long)div_u64(l->sum_time, l->count),
3714 l->max_time);
Christoph Lameter45edfa52007-05-09 02:32:45 -07003715 } else
Harvey Harrisone374d482008-01-31 15:20:50 -08003716 len += sprintf(buf + len, " age=%ld",
Christoph Lameter45edfa52007-05-09 02:32:45 -07003717 l->min_time);
3718
3719 if (l->min_pid != l->max_pid)
Harvey Harrisone374d482008-01-31 15:20:50 -08003720 len += sprintf(buf + len, " pid=%ld-%ld",
Christoph Lameter45edfa52007-05-09 02:32:45 -07003721 l->min_pid, l->max_pid);
3722 else
Harvey Harrisone374d482008-01-31 15:20:50 -08003723 len += sprintf(buf + len, " pid=%ld",
Christoph Lameter45edfa52007-05-09 02:32:45 -07003724 l->min_pid);
3725
Rusty Russell174596a2009-01-01 10:12:29 +10303726 if (num_online_cpus() > 1 &&
3727 !cpumask_empty(to_cpumask(l->cpus)) &&
Harvey Harrisone374d482008-01-31 15:20:50 -08003728 len < PAGE_SIZE - 60) {
3729 len += sprintf(buf + len, " cpus=");
3730 len += cpulist_scnprintf(buf + len, PAGE_SIZE - len - 50,
Rusty Russell174596a2009-01-01 10:12:29 +10303731 to_cpumask(l->cpus));
Christoph Lameter45edfa52007-05-09 02:32:45 -07003732 }
3733
Christoph Lameter62bc62a2009-06-16 15:32:15 -07003734 if (nr_online_nodes > 1 && !nodes_empty(l->nodes) &&
Harvey Harrisone374d482008-01-31 15:20:50 -08003735 len < PAGE_SIZE - 60) {
3736 len += sprintf(buf + len, " nodes=");
3737 len += nodelist_scnprintf(buf + len, PAGE_SIZE - len - 50,
Christoph Lameter45edfa52007-05-09 02:32:45 -07003738 l->nodes);
3739 }
3740
Harvey Harrisone374d482008-01-31 15:20:50 -08003741 len += sprintf(buf + len, "\n");
Christoph Lameter88a420e2007-05-06 14:49:45 -07003742 }
3743
3744 free_loc_track(&t);
Eric Dumazetbbd7d572010-03-24 22:25:47 +01003745 kfree(map);
Christoph Lameter88a420e2007-05-06 14:49:45 -07003746 if (!t.count)
Harvey Harrisone374d482008-01-31 15:20:50 -08003747 len += sprintf(buf, "No data\n");
3748 return len;
Christoph Lameter88a420e2007-05-06 14:49:45 -07003749}
3750
Christoph Lameter81819f02007-05-06 14:49:36 -07003751enum slab_stat_type {
Christoph Lameter205ab992008-04-14 19:11:40 +03003752 SL_ALL, /* All slabs */
3753 SL_PARTIAL, /* Only partially allocated slabs */
3754 SL_CPU, /* Only slabs used for cpu caches */
3755 SL_OBJECTS, /* Determine allocated objects not slabs */
3756 SL_TOTAL /* Determine object capacity not slabs */
Christoph Lameter81819f02007-05-06 14:49:36 -07003757};
3758
Christoph Lameter205ab992008-04-14 19:11:40 +03003759#define SO_ALL (1 << SL_ALL)
Christoph Lameter81819f02007-05-06 14:49:36 -07003760#define SO_PARTIAL (1 << SL_PARTIAL)
3761#define SO_CPU (1 << SL_CPU)
3762#define SO_OBJECTS (1 << SL_OBJECTS)
Christoph Lameter205ab992008-04-14 19:11:40 +03003763#define SO_TOTAL (1 << SL_TOTAL)
Christoph Lameter81819f02007-05-06 14:49:36 -07003764
Cyrill Gorcunov62e5c4b2008-03-02 23:28:24 +03003765static ssize_t show_slab_objects(struct kmem_cache *s,
3766 char *buf, unsigned long flags)
Christoph Lameter81819f02007-05-06 14:49:36 -07003767{
3768 unsigned long total = 0;
Christoph Lameter81819f02007-05-06 14:49:36 -07003769 int node;
3770 int x;
3771 unsigned long *nodes;
3772 unsigned long *per_cpu;
3773
3774 nodes = kzalloc(2 * sizeof(unsigned long) * nr_node_ids, GFP_KERNEL);
Cyrill Gorcunov62e5c4b2008-03-02 23:28:24 +03003775 if (!nodes)
3776 return -ENOMEM;
Christoph Lameter81819f02007-05-06 14:49:36 -07003777 per_cpu = nodes + nr_node_ids;
3778
Christoph Lameter205ab992008-04-14 19:11:40 +03003779 if (flags & SO_CPU) {
3780 int cpu;
Christoph Lameter81819f02007-05-06 14:49:36 -07003781
Christoph Lameter205ab992008-04-14 19:11:40 +03003782 for_each_possible_cpu(cpu) {
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06003783 struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu);
Christoph Lameterdfb4f092007-10-16 01:26:05 -07003784
Christoph Lameter205ab992008-04-14 19:11:40 +03003785 if (!c || c->node < 0)
3786 continue;
3787
3788 if (c->page) {
3789 if (flags & SO_TOTAL)
3790 x = c->page->objects;
3791 else if (flags & SO_OBJECTS)
3792 x = c->page->inuse;
Christoph Lameter81819f02007-05-06 14:49:36 -07003793 else
3794 x = 1;
Christoph Lameter205ab992008-04-14 19:11:40 +03003795
Christoph Lameter81819f02007-05-06 14:49:36 -07003796 total += x;
Christoph Lameter205ab992008-04-14 19:11:40 +03003797 nodes[c->node] += x;
Christoph Lameter81819f02007-05-06 14:49:36 -07003798 }
Christoph Lameter205ab992008-04-14 19:11:40 +03003799 per_cpu[c->node]++;
Christoph Lameter81819f02007-05-06 14:49:36 -07003800 }
3801 }
3802
Christoph Lameter205ab992008-04-14 19:11:40 +03003803 if (flags & SO_ALL) {
3804 for_each_node_state(node, N_NORMAL_MEMORY) {
3805 struct kmem_cache_node *n = get_node(s, node);
Christoph Lameter81819f02007-05-06 14:49:36 -07003806
Christoph Lameter205ab992008-04-14 19:11:40 +03003807 if (flags & SO_TOTAL)
3808 x = atomic_long_read(&n->total_objects);
3809 else if (flags & SO_OBJECTS)
3810 x = atomic_long_read(&n->total_objects) -
3811 count_partial(n, count_free);
3812
3813 else
3814 x = atomic_long_read(&n->nr_slabs);
3815 total += x;
3816 nodes[node] += x;
3817 }
3818
3819 } else if (flags & SO_PARTIAL) {
3820 for_each_node_state(node, N_NORMAL_MEMORY) {
3821 struct kmem_cache_node *n = get_node(s, node);
3822
3823 if (flags & SO_TOTAL)
3824 x = count_partial(n, count_total);
3825 else if (flags & SO_OBJECTS)
3826 x = count_partial(n, count_inuse);
Christoph Lameter81819f02007-05-06 14:49:36 -07003827 else
3828 x = n->nr_partial;
3829 total += x;
3830 nodes[node] += x;
3831 }
Christoph Lameter81819f02007-05-06 14:49:36 -07003832 }
Christoph Lameter81819f02007-05-06 14:49:36 -07003833 x = sprintf(buf, "%lu", total);
3834#ifdef CONFIG_NUMA
Christoph Lameterf64dc582007-10-16 01:25:33 -07003835 for_each_node_state(node, N_NORMAL_MEMORY)
Christoph Lameter81819f02007-05-06 14:49:36 -07003836 if (nodes[node])
3837 x += sprintf(buf + x, " N%d=%lu",
3838 node, nodes[node]);
3839#endif
3840 kfree(nodes);
3841 return x + sprintf(buf + x, "\n");
3842}
3843
3844static int any_slab_objects(struct kmem_cache *s)
3845{
3846 int node;
Christoph Lameterdfb4f092007-10-16 01:26:05 -07003847
3848 for_each_online_node(node) {
Christoph Lameter81819f02007-05-06 14:49:36 -07003849 struct kmem_cache_node *n = get_node(s, node);
3850
Christoph Lameterdfb4f092007-10-16 01:26:05 -07003851 if (!n)
3852 continue;
3853
Benjamin Herrenschmidt4ea33e22008-05-06 20:42:39 -07003854 if (atomic_long_read(&n->total_objects))
Christoph Lameter81819f02007-05-06 14:49:36 -07003855 return 1;
3856 }
3857 return 0;
3858}
3859
3860#define to_slab_attr(n) container_of(n, struct slab_attribute, attr)
3861#define to_slab(n) container_of(n, struct kmem_cache, kobj);
3862
3863struct slab_attribute {
3864 struct attribute attr;
3865 ssize_t (*show)(struct kmem_cache *s, char *buf);
3866 ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count);
3867};
3868
3869#define SLAB_ATTR_RO(_name) \
3870 static struct slab_attribute _name##_attr = __ATTR_RO(_name)
3871
3872#define SLAB_ATTR(_name) \
3873 static struct slab_attribute _name##_attr = \
3874 __ATTR(_name, 0644, _name##_show, _name##_store)
3875
Christoph Lameter81819f02007-05-06 14:49:36 -07003876static ssize_t slab_size_show(struct kmem_cache *s, char *buf)
3877{
3878 return sprintf(buf, "%d\n", s->size);
3879}
3880SLAB_ATTR_RO(slab_size);
3881
3882static ssize_t align_show(struct kmem_cache *s, char *buf)
3883{
3884 return sprintf(buf, "%d\n", s->align);
3885}
3886SLAB_ATTR_RO(align);
3887
3888static ssize_t object_size_show(struct kmem_cache *s, char *buf)
3889{
3890 return sprintf(buf, "%d\n", s->objsize);
3891}
3892SLAB_ATTR_RO(object_size);
3893
3894static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf)
3895{
Christoph Lameter834f3d12008-04-14 19:11:31 +03003896 return sprintf(buf, "%d\n", oo_objects(s->oo));
Christoph Lameter81819f02007-05-06 14:49:36 -07003897}
3898SLAB_ATTR_RO(objs_per_slab);
3899
Christoph Lameter06b285d2008-04-14 19:11:41 +03003900static ssize_t order_store(struct kmem_cache *s,
3901 const char *buf, size_t length)
3902{
Christoph Lameter0121c6192008-04-29 16:11:12 -07003903 unsigned long order;
3904 int err;
3905
3906 err = strict_strtoul(buf, 10, &order);
3907 if (err)
3908 return err;
Christoph Lameter06b285d2008-04-14 19:11:41 +03003909
3910 if (order > slub_max_order || order < slub_min_order)
3911 return -EINVAL;
3912
3913 calculate_sizes(s, order);
3914 return length;
3915}
3916
Christoph Lameter81819f02007-05-06 14:49:36 -07003917static ssize_t order_show(struct kmem_cache *s, char *buf)
3918{
Christoph Lameter834f3d12008-04-14 19:11:31 +03003919 return sprintf(buf, "%d\n", oo_order(s->oo));
Christoph Lameter81819f02007-05-06 14:49:36 -07003920}
Christoph Lameter06b285d2008-04-14 19:11:41 +03003921SLAB_ATTR(order);
Christoph Lameter81819f02007-05-06 14:49:36 -07003922
David Rientjes73d342b2009-02-22 17:40:09 -08003923static ssize_t min_partial_show(struct kmem_cache *s, char *buf)
3924{
3925 return sprintf(buf, "%lu\n", s->min_partial);
3926}
3927
3928static ssize_t min_partial_store(struct kmem_cache *s, const char *buf,
3929 size_t length)
3930{
3931 unsigned long min;
3932 int err;
3933
3934 err = strict_strtoul(buf, 10, &min);
3935 if (err)
3936 return err;
3937
David Rientjesc0bdb232009-02-25 09:16:35 +02003938 set_min_partial(s, min);
David Rientjes73d342b2009-02-22 17:40:09 -08003939 return length;
3940}
3941SLAB_ATTR(min_partial);
3942
Christoph Lameter81819f02007-05-06 14:49:36 -07003943static ssize_t ctor_show(struct kmem_cache *s, char *buf)
3944{
3945 if (s->ctor) {
3946 int n = sprint_symbol(buf, (unsigned long)s->ctor);
3947
3948 return n + sprintf(buf + n, "\n");
3949 }
3950 return 0;
3951}
3952SLAB_ATTR_RO(ctor);
3953
Christoph Lameter81819f02007-05-06 14:49:36 -07003954static ssize_t aliases_show(struct kmem_cache *s, char *buf)
3955{
3956 return sprintf(buf, "%d\n", s->refcount - 1);
3957}
3958SLAB_ATTR_RO(aliases);
3959
3960static ssize_t slabs_show(struct kmem_cache *s, char *buf)
3961{
Christoph Lameter205ab992008-04-14 19:11:40 +03003962 return show_slab_objects(s, buf, SO_ALL);
Christoph Lameter81819f02007-05-06 14:49:36 -07003963}
3964SLAB_ATTR_RO(slabs);
3965
3966static ssize_t partial_show(struct kmem_cache *s, char *buf)
3967{
Christoph Lameterd9acf4b2008-02-15 15:22:21 -08003968 return show_slab_objects(s, buf, SO_PARTIAL);
Christoph Lameter81819f02007-05-06 14:49:36 -07003969}
3970SLAB_ATTR_RO(partial);
3971
3972static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf)
3973{
Christoph Lameterd9acf4b2008-02-15 15:22:21 -08003974 return show_slab_objects(s, buf, SO_CPU);
Christoph Lameter81819f02007-05-06 14:49:36 -07003975}
3976SLAB_ATTR_RO(cpu_slabs);
3977
3978static ssize_t objects_show(struct kmem_cache *s, char *buf)
3979{
Christoph Lameter205ab992008-04-14 19:11:40 +03003980 return show_slab_objects(s, buf, SO_ALL|SO_OBJECTS);
Christoph Lameter81819f02007-05-06 14:49:36 -07003981}
3982SLAB_ATTR_RO(objects);
3983
Christoph Lameter205ab992008-04-14 19:11:40 +03003984static ssize_t objects_partial_show(struct kmem_cache *s, char *buf)
3985{
3986 return show_slab_objects(s, buf, SO_PARTIAL|SO_OBJECTS);
3987}
3988SLAB_ATTR_RO(objects_partial);
3989
3990static ssize_t total_objects_show(struct kmem_cache *s, char *buf)
3991{
3992 return show_slab_objects(s, buf, SO_ALL|SO_TOTAL);
3993}
3994SLAB_ATTR_RO(total_objects);
3995
Christoph Lameter81819f02007-05-06 14:49:36 -07003996static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf)
3997{
3998 return sprintf(buf, "%d\n", !!(s->flags & SLAB_DEBUG_FREE));
3999}
4000
4001static ssize_t sanity_checks_store(struct kmem_cache *s,
4002 const char *buf, size_t length)
4003{
4004 s->flags &= ~SLAB_DEBUG_FREE;
4005 if (buf[0] == '1')
4006 s->flags |= SLAB_DEBUG_FREE;
4007 return length;
4008}
4009SLAB_ATTR(sanity_checks);
4010
4011static ssize_t trace_show(struct kmem_cache *s, char *buf)
4012{
4013 return sprintf(buf, "%d\n", !!(s->flags & SLAB_TRACE));
4014}
4015
4016static ssize_t trace_store(struct kmem_cache *s, const char *buf,
4017 size_t length)
4018{
4019 s->flags &= ~SLAB_TRACE;
4020 if (buf[0] == '1')
4021 s->flags |= SLAB_TRACE;
4022 return length;
4023}
4024SLAB_ATTR(trace);
4025
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +03004026#ifdef CONFIG_FAILSLAB
4027static ssize_t failslab_show(struct kmem_cache *s, char *buf)
4028{
4029 return sprintf(buf, "%d\n", !!(s->flags & SLAB_FAILSLAB));
4030}
4031
4032static ssize_t failslab_store(struct kmem_cache *s, const char *buf,
4033 size_t length)
4034{
4035 s->flags &= ~SLAB_FAILSLAB;
4036 if (buf[0] == '1')
4037 s->flags |= SLAB_FAILSLAB;
4038 return length;
4039}
4040SLAB_ATTR(failslab);
4041#endif
4042
Christoph Lameter81819f02007-05-06 14:49:36 -07004043static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf)
4044{
4045 return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT));
4046}
4047
4048static ssize_t reclaim_account_store(struct kmem_cache *s,
4049 const char *buf, size_t length)
4050{
4051 s->flags &= ~SLAB_RECLAIM_ACCOUNT;
4052 if (buf[0] == '1')
4053 s->flags |= SLAB_RECLAIM_ACCOUNT;
4054 return length;
4055}
4056SLAB_ATTR(reclaim_account);
4057
4058static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf)
4059{
Christoph Lameter5af60832007-05-06 14:49:56 -07004060 return sprintf(buf, "%d\n", !!(s->flags & SLAB_HWCACHE_ALIGN));
Christoph Lameter81819f02007-05-06 14:49:36 -07004061}
4062SLAB_ATTR_RO(hwcache_align);
4063
4064#ifdef CONFIG_ZONE_DMA
4065static ssize_t cache_dma_show(struct kmem_cache *s, char *buf)
4066{
4067 return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA));
4068}
4069SLAB_ATTR_RO(cache_dma);
4070#endif
4071
4072static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf)
4073{
4074 return sprintf(buf, "%d\n", !!(s->flags & SLAB_DESTROY_BY_RCU));
4075}
4076SLAB_ATTR_RO(destroy_by_rcu);
4077
4078static ssize_t red_zone_show(struct kmem_cache *s, char *buf)
4079{
4080 return sprintf(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE));
4081}
4082
4083static ssize_t red_zone_store(struct kmem_cache *s,
4084 const char *buf, size_t length)
4085{
4086 if (any_slab_objects(s))
4087 return -EBUSY;
4088
4089 s->flags &= ~SLAB_RED_ZONE;
4090 if (buf[0] == '1')
4091 s->flags |= SLAB_RED_ZONE;
Christoph Lameter06b285d2008-04-14 19:11:41 +03004092 calculate_sizes(s, -1);
Christoph Lameter81819f02007-05-06 14:49:36 -07004093 return length;
4094}
4095SLAB_ATTR(red_zone);
4096
4097static ssize_t poison_show(struct kmem_cache *s, char *buf)
4098{
4099 return sprintf(buf, "%d\n", !!(s->flags & SLAB_POISON));
4100}
4101
4102static ssize_t poison_store(struct kmem_cache *s,
4103 const char *buf, size_t length)
4104{
4105 if (any_slab_objects(s))
4106 return -EBUSY;
4107
4108 s->flags &= ~SLAB_POISON;
4109 if (buf[0] == '1')
4110 s->flags |= SLAB_POISON;
Christoph Lameter06b285d2008-04-14 19:11:41 +03004111 calculate_sizes(s, -1);
Christoph Lameter81819f02007-05-06 14:49:36 -07004112 return length;
4113}
4114SLAB_ATTR(poison);
4115
4116static ssize_t store_user_show(struct kmem_cache *s, char *buf)
4117{
4118 return sprintf(buf, "%d\n", !!(s->flags & SLAB_STORE_USER));
4119}
4120
4121static ssize_t store_user_store(struct kmem_cache *s,
4122 const char *buf, size_t length)
4123{
4124 if (any_slab_objects(s))
4125 return -EBUSY;
4126
4127 s->flags &= ~SLAB_STORE_USER;
4128 if (buf[0] == '1')
4129 s->flags |= SLAB_STORE_USER;
Christoph Lameter06b285d2008-04-14 19:11:41 +03004130 calculate_sizes(s, -1);
Christoph Lameter81819f02007-05-06 14:49:36 -07004131 return length;
4132}
4133SLAB_ATTR(store_user);
4134
Christoph Lameter53e15af2007-05-06 14:49:43 -07004135static ssize_t validate_show(struct kmem_cache *s, char *buf)
4136{
4137 return 0;
4138}
4139
4140static ssize_t validate_store(struct kmem_cache *s,
4141 const char *buf, size_t length)
4142{
Christoph Lameter434e2452007-07-17 04:03:30 -07004143 int ret = -EINVAL;
4144
4145 if (buf[0] == '1') {
4146 ret = validate_slab_cache(s);
4147 if (ret >= 0)
4148 ret = length;
4149 }
4150 return ret;
Christoph Lameter53e15af2007-05-06 14:49:43 -07004151}
4152SLAB_ATTR(validate);
4153
Christoph Lameter2086d262007-05-06 14:49:46 -07004154static ssize_t shrink_show(struct kmem_cache *s, char *buf)
4155{
4156 return 0;
4157}
4158
4159static ssize_t shrink_store(struct kmem_cache *s,
4160 const char *buf, size_t length)
4161{
4162 if (buf[0] == '1') {
4163 int rc = kmem_cache_shrink(s);
4164
4165 if (rc)
4166 return rc;
4167 } else
4168 return -EINVAL;
4169 return length;
4170}
4171SLAB_ATTR(shrink);
4172
Christoph Lameter88a420e2007-05-06 14:49:45 -07004173static ssize_t alloc_calls_show(struct kmem_cache *s, char *buf)
4174{
4175 if (!(s->flags & SLAB_STORE_USER))
4176 return -ENOSYS;
4177 return list_locations(s, buf, TRACK_ALLOC);
4178}
4179SLAB_ATTR_RO(alloc_calls);
4180
4181static ssize_t free_calls_show(struct kmem_cache *s, char *buf)
4182{
4183 if (!(s->flags & SLAB_STORE_USER))
4184 return -ENOSYS;
4185 return list_locations(s, buf, TRACK_FREE);
4186}
4187SLAB_ATTR_RO(free_calls);
4188
Christoph Lameter81819f02007-05-06 14:49:36 -07004189#ifdef CONFIG_NUMA
Christoph Lameter98246012008-01-07 23:20:26 -08004190static ssize_t remote_node_defrag_ratio_show(struct kmem_cache *s, char *buf)
Christoph Lameter81819f02007-05-06 14:49:36 -07004191{
Christoph Lameter98246012008-01-07 23:20:26 -08004192 return sprintf(buf, "%d\n", s->remote_node_defrag_ratio / 10);
Christoph Lameter81819f02007-05-06 14:49:36 -07004193}
4194
Christoph Lameter98246012008-01-07 23:20:26 -08004195static ssize_t remote_node_defrag_ratio_store(struct kmem_cache *s,
Christoph Lameter81819f02007-05-06 14:49:36 -07004196 const char *buf, size_t length)
4197{
Christoph Lameter0121c6192008-04-29 16:11:12 -07004198 unsigned long ratio;
4199 int err;
Christoph Lameter81819f02007-05-06 14:49:36 -07004200
Christoph Lameter0121c6192008-04-29 16:11:12 -07004201 err = strict_strtoul(buf, 10, &ratio);
4202 if (err)
4203 return err;
4204
Christoph Lametere2cb96b2008-08-19 08:51:22 -05004205 if (ratio <= 100)
Christoph Lameter0121c6192008-04-29 16:11:12 -07004206 s->remote_node_defrag_ratio = ratio * 10;
4207
Christoph Lameter81819f02007-05-06 14:49:36 -07004208 return length;
4209}
Christoph Lameter98246012008-01-07 23:20:26 -08004210SLAB_ATTR(remote_node_defrag_ratio);
Christoph Lameter81819f02007-05-06 14:49:36 -07004211#endif
4212
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004213#ifdef CONFIG_SLUB_STATS
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004214static int show_stat(struct kmem_cache *s, char *buf, enum stat_item si)
4215{
4216 unsigned long sum = 0;
4217 int cpu;
4218 int len;
4219 int *data = kmalloc(nr_cpu_ids * sizeof(int), GFP_KERNEL);
4220
4221 if (!data)
4222 return -ENOMEM;
4223
4224 for_each_online_cpu(cpu) {
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06004225 unsigned x = per_cpu_ptr(s->cpu_slab, cpu)->stat[si];
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004226
4227 data[cpu] = x;
4228 sum += x;
4229 }
4230
4231 len = sprintf(buf, "%lu", sum);
4232
Christoph Lameter50ef37b2008-04-14 18:52:05 +03004233#ifdef CONFIG_SMP
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004234 for_each_online_cpu(cpu) {
4235 if (data[cpu] && len < PAGE_SIZE - 20)
Christoph Lameter50ef37b2008-04-14 18:52:05 +03004236 len += sprintf(buf + len, " C%d=%u", cpu, data[cpu]);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004237 }
Christoph Lameter50ef37b2008-04-14 18:52:05 +03004238#endif
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004239 kfree(data);
4240 return len + sprintf(buf + len, "\n");
4241}
4242
David Rientjes78eb00c2009-10-15 02:20:22 -07004243static void clear_stat(struct kmem_cache *s, enum stat_item si)
4244{
4245 int cpu;
4246
4247 for_each_online_cpu(cpu)
Christoph Lameter9dfc6e62009-12-18 16:26:20 -06004248 per_cpu_ptr(s->cpu_slab, cpu)->stat[si] = 0;
David Rientjes78eb00c2009-10-15 02:20:22 -07004249}
4250
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004251#define STAT_ATTR(si, text) \
4252static ssize_t text##_show(struct kmem_cache *s, char *buf) \
4253{ \
4254 return show_stat(s, buf, si); \
4255} \
David Rientjes78eb00c2009-10-15 02:20:22 -07004256static ssize_t text##_store(struct kmem_cache *s, \
4257 const char *buf, size_t length) \
4258{ \
4259 if (buf[0] != '0') \
4260 return -EINVAL; \
4261 clear_stat(s, si); \
4262 return length; \
4263} \
4264SLAB_ATTR(text); \
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004265
4266STAT_ATTR(ALLOC_FASTPATH, alloc_fastpath);
4267STAT_ATTR(ALLOC_SLOWPATH, alloc_slowpath);
4268STAT_ATTR(FREE_FASTPATH, free_fastpath);
4269STAT_ATTR(FREE_SLOWPATH, free_slowpath);
4270STAT_ATTR(FREE_FROZEN, free_frozen);
4271STAT_ATTR(FREE_ADD_PARTIAL, free_add_partial);
4272STAT_ATTR(FREE_REMOVE_PARTIAL, free_remove_partial);
4273STAT_ATTR(ALLOC_FROM_PARTIAL, alloc_from_partial);
4274STAT_ATTR(ALLOC_SLAB, alloc_slab);
4275STAT_ATTR(ALLOC_REFILL, alloc_refill);
4276STAT_ATTR(FREE_SLAB, free_slab);
4277STAT_ATTR(CPUSLAB_FLUSH, cpuslab_flush);
4278STAT_ATTR(DEACTIVATE_FULL, deactivate_full);
4279STAT_ATTR(DEACTIVATE_EMPTY, deactivate_empty);
4280STAT_ATTR(DEACTIVATE_TO_HEAD, deactivate_to_head);
4281STAT_ATTR(DEACTIVATE_TO_TAIL, deactivate_to_tail);
4282STAT_ATTR(DEACTIVATE_REMOTE_FREES, deactivate_remote_frees);
Christoph Lameter65c33762008-04-14 19:11:40 +03004283STAT_ATTR(ORDER_FALLBACK, order_fallback);
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004284#endif
4285
Pekka Enberg06428782008-01-07 23:20:27 -08004286static struct attribute *slab_attrs[] = {
Christoph Lameter81819f02007-05-06 14:49:36 -07004287 &slab_size_attr.attr,
4288 &object_size_attr.attr,
4289 &objs_per_slab_attr.attr,
4290 &order_attr.attr,
David Rientjes73d342b2009-02-22 17:40:09 -08004291 &min_partial_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004292 &objects_attr.attr,
Christoph Lameter205ab992008-04-14 19:11:40 +03004293 &objects_partial_attr.attr,
4294 &total_objects_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004295 &slabs_attr.attr,
4296 &partial_attr.attr,
4297 &cpu_slabs_attr.attr,
4298 &ctor_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004299 &aliases_attr.attr,
4300 &align_attr.attr,
4301 &sanity_checks_attr.attr,
4302 &trace_attr.attr,
4303 &hwcache_align_attr.attr,
4304 &reclaim_account_attr.attr,
4305 &destroy_by_rcu_attr.attr,
4306 &red_zone_attr.attr,
4307 &poison_attr.attr,
4308 &store_user_attr.attr,
Christoph Lameter53e15af2007-05-06 14:49:43 -07004309 &validate_attr.attr,
Christoph Lameter2086d262007-05-06 14:49:46 -07004310 &shrink_attr.attr,
Christoph Lameter88a420e2007-05-06 14:49:45 -07004311 &alloc_calls_attr.attr,
4312 &free_calls_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004313#ifdef CONFIG_ZONE_DMA
4314 &cache_dma_attr.attr,
4315#endif
4316#ifdef CONFIG_NUMA
Christoph Lameter98246012008-01-07 23:20:26 -08004317 &remote_node_defrag_ratio_attr.attr,
Christoph Lameter81819f02007-05-06 14:49:36 -07004318#endif
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004319#ifdef CONFIG_SLUB_STATS
4320 &alloc_fastpath_attr.attr,
4321 &alloc_slowpath_attr.attr,
4322 &free_fastpath_attr.attr,
4323 &free_slowpath_attr.attr,
4324 &free_frozen_attr.attr,
4325 &free_add_partial_attr.attr,
4326 &free_remove_partial_attr.attr,
4327 &alloc_from_partial_attr.attr,
4328 &alloc_slab_attr.attr,
4329 &alloc_refill_attr.attr,
4330 &free_slab_attr.attr,
4331 &cpuslab_flush_attr.attr,
4332 &deactivate_full_attr.attr,
4333 &deactivate_empty_attr.attr,
4334 &deactivate_to_head_attr.attr,
4335 &deactivate_to_tail_attr.attr,
4336 &deactivate_remote_frees_attr.attr,
Christoph Lameter65c33762008-04-14 19:11:40 +03004337 &order_fallback_attr.attr,
Christoph Lameter8ff12cf2008-02-07 17:47:41 -08004338#endif
Dmitry Monakhov4c13dd32010-02-26 09:36:12 +03004339#ifdef CONFIG_FAILSLAB
4340 &failslab_attr.attr,
4341#endif
4342
Christoph Lameter81819f02007-05-06 14:49:36 -07004343 NULL
4344};
4345
4346static struct attribute_group slab_attr_group = {
4347 .attrs = slab_attrs,
4348};
4349
4350static ssize_t slab_attr_show(struct kobject *kobj,
4351 struct attribute *attr,
4352 char *buf)
4353{
4354 struct slab_attribute *attribute;
4355 struct kmem_cache *s;
4356 int err;
4357
4358 attribute = to_slab_attr(attr);
4359 s = to_slab(kobj);
4360
4361 if (!attribute->show)
4362 return -EIO;
4363
4364 err = attribute->show(s, buf);
4365
4366 return err;
4367}
4368
4369static ssize_t slab_attr_store(struct kobject *kobj,
4370 struct attribute *attr,
4371 const char *buf, size_t len)
4372{
4373 struct slab_attribute *attribute;
4374 struct kmem_cache *s;
4375 int err;
4376
4377 attribute = to_slab_attr(attr);
4378 s = to_slab(kobj);
4379
4380 if (!attribute->store)
4381 return -EIO;
4382
4383 err = attribute->store(s, buf, len);
4384
4385 return err;
4386}
4387
Christoph Lameter151c6022008-01-07 22:29:05 -08004388static void kmem_cache_release(struct kobject *kobj)
4389{
4390 struct kmem_cache *s = to_slab(kobj);
4391
4392 kfree(s);
4393}
4394
Emese Revfy52cf25d2010-01-19 02:58:23 +01004395static const struct sysfs_ops slab_sysfs_ops = {
Christoph Lameter81819f02007-05-06 14:49:36 -07004396 .show = slab_attr_show,
4397 .store = slab_attr_store,
4398};
4399
4400static struct kobj_type slab_ktype = {
4401 .sysfs_ops = &slab_sysfs_ops,
Christoph Lameter151c6022008-01-07 22:29:05 -08004402 .release = kmem_cache_release
Christoph Lameter81819f02007-05-06 14:49:36 -07004403};
4404
4405static int uevent_filter(struct kset *kset, struct kobject *kobj)
4406{
4407 struct kobj_type *ktype = get_ktype(kobj);
4408
4409 if (ktype == &slab_ktype)
4410 return 1;
4411 return 0;
4412}
4413
Emese Revfy9cd43612009-12-31 14:52:51 +01004414static const struct kset_uevent_ops slab_uevent_ops = {
Christoph Lameter81819f02007-05-06 14:49:36 -07004415 .filter = uevent_filter,
4416};
4417
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06004418static struct kset *slab_kset;
Christoph Lameter81819f02007-05-06 14:49:36 -07004419
4420#define ID_STR_LENGTH 64
4421
4422/* Create a unique string id for a slab cache:
Christoph Lameter6446faa2008-02-15 23:45:26 -08004423 *
4424 * Format :[flags-]size
Christoph Lameter81819f02007-05-06 14:49:36 -07004425 */
4426static char *create_unique_id(struct kmem_cache *s)
4427{
4428 char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL);
4429 char *p = name;
4430
4431 BUG_ON(!name);
4432
4433 *p++ = ':';
4434 /*
4435 * First flags affecting slabcache operations. We will only
4436 * get here for aliasable slabs so we do not need to support
4437 * too many flags. The flags here must cover all flags that
4438 * are matched during merging to guarantee that the id is
4439 * unique.
4440 */
4441 if (s->flags & SLAB_CACHE_DMA)
4442 *p++ = 'd';
4443 if (s->flags & SLAB_RECLAIM_ACCOUNT)
4444 *p++ = 'a';
4445 if (s->flags & SLAB_DEBUG_FREE)
4446 *p++ = 'F';
Vegard Nossum5a896d92008-04-04 00:54:48 +02004447 if (!(s->flags & SLAB_NOTRACK))
4448 *p++ = 't';
Christoph Lameter81819f02007-05-06 14:49:36 -07004449 if (p != name + 1)
4450 *p++ = '-';
4451 p += sprintf(p, "%07d", s->size);
4452 BUG_ON(p > name + ID_STR_LENGTH - 1);
4453 return name;
4454}
4455
4456static int sysfs_slab_add(struct kmem_cache *s)
4457{
4458 int err;
4459 const char *name;
4460 int unmergeable;
4461
4462 if (slab_state < SYSFS)
4463 /* Defer until later */
4464 return 0;
4465
4466 unmergeable = slab_unmergeable(s);
4467 if (unmergeable) {
4468 /*
4469 * Slabcache can never be merged so we can use the name proper.
4470 * This is typically the case for debug situations. In that
4471 * case we can catch duplicate names easily.
4472 */
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06004473 sysfs_remove_link(&slab_kset->kobj, s->name);
Christoph Lameter81819f02007-05-06 14:49:36 -07004474 name = s->name;
4475 } else {
4476 /*
4477 * Create a unique name for the slab as a target
4478 * for the symlinks.
4479 */
4480 name = create_unique_id(s);
4481 }
4482
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06004483 s->kobj.kset = slab_kset;
Greg Kroah-Hartman1eada112007-12-17 23:05:35 -07004484 err = kobject_init_and_add(&s->kobj, &slab_ktype, NULL, name);
4485 if (err) {
4486 kobject_put(&s->kobj);
Christoph Lameter81819f02007-05-06 14:49:36 -07004487 return err;
Greg Kroah-Hartman1eada112007-12-17 23:05:35 -07004488 }
Christoph Lameter81819f02007-05-06 14:49:36 -07004489
4490 err = sysfs_create_group(&s->kobj, &slab_attr_group);
Xiaotian Feng5788d8a2009-07-22 11:28:53 +08004491 if (err) {
4492 kobject_del(&s->kobj);
4493 kobject_put(&s->kobj);
Christoph Lameter81819f02007-05-06 14:49:36 -07004494 return err;
Xiaotian Feng5788d8a2009-07-22 11:28:53 +08004495 }
Christoph Lameter81819f02007-05-06 14:49:36 -07004496 kobject_uevent(&s->kobj, KOBJ_ADD);
4497 if (!unmergeable) {
4498 /* Setup first alias */
4499 sysfs_slab_alias(s, s->name);
4500 kfree(name);
4501 }
4502 return 0;
4503}
4504
4505static void sysfs_slab_remove(struct kmem_cache *s)
4506{
4507 kobject_uevent(&s->kobj, KOBJ_REMOVE);
4508 kobject_del(&s->kobj);
Christoph Lameter151c6022008-01-07 22:29:05 -08004509 kobject_put(&s->kobj);
Christoph Lameter81819f02007-05-06 14:49:36 -07004510}
4511
4512/*
4513 * Need to buffer aliases during bootup until sysfs becomes
Nick Andrew9f6c708e2008-12-05 14:08:08 +11004514 * available lest we lose that information.
Christoph Lameter81819f02007-05-06 14:49:36 -07004515 */
4516struct saved_alias {
4517 struct kmem_cache *s;
4518 const char *name;
4519 struct saved_alias *next;
4520};
4521
Adrian Bunk5af328a2007-07-17 04:03:27 -07004522static struct saved_alias *alias_list;
Christoph Lameter81819f02007-05-06 14:49:36 -07004523
4524static int sysfs_slab_alias(struct kmem_cache *s, const char *name)
4525{
4526 struct saved_alias *al;
4527
4528 if (slab_state == SYSFS) {
4529 /*
4530 * If we have a leftover link then remove it.
4531 */
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06004532 sysfs_remove_link(&slab_kset->kobj, name);
4533 return sysfs_create_link(&slab_kset->kobj, &s->kobj, name);
Christoph Lameter81819f02007-05-06 14:49:36 -07004534 }
4535
4536 al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL);
4537 if (!al)
4538 return -ENOMEM;
4539
4540 al->s = s;
4541 al->name = name;
4542 al->next = alias_list;
4543 alias_list = al;
4544 return 0;
4545}
4546
4547static int __init slab_sysfs_init(void)
4548{
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07004549 struct kmem_cache *s;
Christoph Lameter81819f02007-05-06 14:49:36 -07004550 int err;
4551
Greg Kroah-Hartman0ff21e42007-11-06 10:36:58 -08004552 slab_kset = kset_create_and_add("slab", &slab_uevent_ops, kernel_kobj);
Greg Kroah-Hartman27c3a312007-11-01 09:29:06 -06004553 if (!slab_kset) {
Christoph Lameter81819f02007-05-06 14:49:36 -07004554 printk(KERN_ERR "Cannot register slab subsystem.\n");
4555 return -ENOSYS;
4556 }
4557
Christoph Lameter26a7bd02007-05-09 02:32:39 -07004558 slab_state = SYSFS;
4559
Christoph Lameter5b95a4ac2007-07-17 04:03:19 -07004560 list_for_each_entry(s, &slab_caches, list) {
Christoph Lameter26a7bd02007-05-09 02:32:39 -07004561 err = sysfs_slab_add(s);
Christoph Lameter5d540fb2007-08-30 23:56:26 -07004562 if (err)
4563 printk(KERN_ERR "SLUB: Unable to add boot slab %s"
4564 " to sysfs\n", s->name);
Christoph Lameter26a7bd02007-05-09 02:32:39 -07004565 }
Christoph Lameter81819f02007-05-06 14:49:36 -07004566
4567 while (alias_list) {
4568 struct saved_alias *al = alias_list;
4569
4570 alias_list = alias_list->next;
4571 err = sysfs_slab_alias(al->s, al->name);
Christoph Lameter5d540fb2007-08-30 23:56:26 -07004572 if (err)
4573 printk(KERN_ERR "SLUB: Unable to add boot slab alias"
4574 " %s to sysfs\n", s->name);
Christoph Lameter81819f02007-05-06 14:49:36 -07004575 kfree(al);
4576 }
4577
4578 resiliency_test();
4579 return 0;
4580}
4581
4582__initcall(slab_sysfs_init);
Christoph Lameter81819f02007-05-06 14:49:36 -07004583#endif
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004584
4585/*
4586 * The /proc/slabinfo ABI
4587 */
Linus Torvalds158a9622008-01-02 13:04:48 -08004588#ifdef CONFIG_SLABINFO
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004589static void print_slabinfo_header(struct seq_file *m)
4590{
4591 seq_puts(m, "slabinfo - version: 2.1\n");
4592 seq_puts(m, "# name <active_objs> <num_objs> <objsize> "
4593 "<objperslab> <pagesperslab>");
4594 seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
4595 seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
4596 seq_putc(m, '\n');
4597}
4598
4599static void *s_start(struct seq_file *m, loff_t *pos)
4600{
4601 loff_t n = *pos;
4602
4603 down_read(&slub_lock);
4604 if (!n)
4605 print_slabinfo_header(m);
4606
4607 return seq_list_start(&slab_caches, *pos);
4608}
4609
4610static void *s_next(struct seq_file *m, void *p, loff_t *pos)
4611{
4612 return seq_list_next(p, &slab_caches, pos);
4613}
4614
4615static void s_stop(struct seq_file *m, void *p)
4616{
4617 up_read(&slub_lock);
4618}
4619
4620static int s_show(struct seq_file *m, void *p)
4621{
4622 unsigned long nr_partials = 0;
4623 unsigned long nr_slabs = 0;
4624 unsigned long nr_inuse = 0;
Christoph Lameter205ab992008-04-14 19:11:40 +03004625 unsigned long nr_objs = 0;
4626 unsigned long nr_free = 0;
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004627 struct kmem_cache *s;
4628 int node;
4629
4630 s = list_entry(p, struct kmem_cache, list);
4631
4632 for_each_online_node(node) {
4633 struct kmem_cache_node *n = get_node(s, node);
4634
4635 if (!n)
4636 continue;
4637
4638 nr_partials += n->nr_partial;
4639 nr_slabs += atomic_long_read(&n->nr_slabs);
Christoph Lameter205ab992008-04-14 19:11:40 +03004640 nr_objs += atomic_long_read(&n->total_objects);
4641 nr_free += count_partial(n, count_free);
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004642 }
4643
Christoph Lameter205ab992008-04-14 19:11:40 +03004644 nr_inuse = nr_objs - nr_free;
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004645
4646 seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d", s->name, nr_inuse,
Christoph Lameter834f3d12008-04-14 19:11:31 +03004647 nr_objs, s->size, oo_objects(s->oo),
4648 (1 << oo_order(s->oo)));
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004649 seq_printf(m, " : tunables %4u %4u %4u", 0, 0, 0);
4650 seq_printf(m, " : slabdata %6lu %6lu %6lu", nr_slabs, nr_slabs,
4651 0UL);
4652 seq_putc(m, '\n');
4653 return 0;
4654}
4655
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +04004656static const struct seq_operations slabinfo_op = {
Pekka J Enberg57ed3ed2008-01-01 17:23:28 +01004657 .start = s_start,
4658 .next = s_next,
4659 .stop = s_stop,
4660 .show = s_show,
4661};
4662
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +04004663static int slabinfo_open(struct inode *inode, struct file *file)
4664{
4665 return seq_open(file, &slabinfo_op);
4666}
4667
4668static const struct file_operations proc_slabinfo_operations = {
4669 .open = slabinfo_open,
4670 .read = seq_read,
4671 .llseek = seq_lseek,
4672 .release = seq_release,
4673};
4674
4675static int __init slab_proc_init(void)
4676{
WANG Congcf5d1132009-08-18 19:11:40 +03004677 proc_create("slabinfo", S_IRUGO, NULL, &proc_slabinfo_operations);
Alexey Dobriyan7b3c3a52008-10-06 02:42:17 +04004678 return 0;
4679}
4680module_init(slab_proc_init);
Linus Torvalds158a9622008-01-02 13:04:48 -08004681#endif /* CONFIG_SLABINFO */