memcg, slab: unregister cache from memcg before starting to destroy it
[linux-2.6-block.git] / mm / slab_common.c
CommitLineData
039363f3
CL
1/*
2 * Slab allocator functions that are independent of the allocator strategy
3 *
4 * (C) 2012 Christoph Lameter <cl@linux.com>
5 */
6#include <linux/slab.h>
7
8#include <linux/mm.h>
9#include <linux/poison.h>
10#include <linux/interrupt.h>
11#include <linux/memory.h>
12#include <linux/compiler.h>
13#include <linux/module.h>
20cea968
CL
14#include <linux/cpu.h>
15#include <linux/uaccess.h>
b7454ad3
GC
16#include <linux/seq_file.h>
17#include <linux/proc_fs.h>
039363f3
CL
18#include <asm/cacheflush.h>
19#include <asm/tlbflush.h>
20#include <asm/page.h>
2633d7a0 21#include <linux/memcontrol.h>
f1b6eb6e 22#include <trace/events/kmem.h>
039363f3 23
97d06609
CL
24#include "slab.h"
25
26enum slab_state slab_state;
18004c5d
CL
27LIST_HEAD(slab_caches);
28DEFINE_MUTEX(slab_mutex);
9b030cb8 29struct kmem_cache *kmem_cache;
97d06609 30
77be4b13 31#ifdef CONFIG_DEBUG_VM
794b1248 32static int kmem_cache_sanity_check(const char *name, size_t size)
039363f3
CL
33{
34 struct kmem_cache *s = NULL;
35
039363f3
CL
36 if (!name || in_interrupt() || size < sizeof(void *) ||
37 size > KMALLOC_MAX_SIZE) {
77be4b13
SK
38 pr_err("kmem_cache_create(%s) integrity check failed\n", name);
39 return -EINVAL;
039363f3 40 }
b920536a 41
20cea968
CL
42 list_for_each_entry(s, &slab_caches, list) {
43 char tmp;
44 int res;
45
46 /*
47 * This happens when the module gets unloaded and doesn't
48 * destroy its slab cache and no-one else reuses the vmalloc
49 * area of the module. Print a warning.
50 */
51 res = probe_kernel_address(s->name, tmp);
52 if (res) {
77be4b13 53 pr_err("Slab cache with size %d has lost its name\n",
20cea968
CL
54 s->object_size);
55 continue;
56 }
57
3e374919 58#if !defined(CONFIG_SLUB) || !defined(CONFIG_SLUB_DEBUG_ON)
794b1248 59 if (!strcmp(s->name, name)) {
77be4b13
SK
60 pr_err("%s (%s): Cache name already exists.\n",
61 __func__, name);
20cea968
CL
62 dump_stack();
63 s = NULL;
77be4b13 64 return -EINVAL;
20cea968 65 }
3e374919 66#endif
20cea968
CL
67 }
68
69 WARN_ON(strchr(name, ' ')); /* It confuses parsers */
77be4b13
SK
70 return 0;
71}
72#else
794b1248 73static inline int kmem_cache_sanity_check(const char *name, size_t size)
77be4b13
SK
74{
75 return 0;
76}
20cea968
CL
77#endif
78
55007d84
GC
79#ifdef CONFIG_MEMCG_KMEM
80int memcg_update_all_caches(int num_memcgs)
81{
82 struct kmem_cache *s;
83 int ret = 0;
84 mutex_lock(&slab_mutex);
85
86 list_for_each_entry(s, &slab_caches, list) {
87 if (!is_root_cache(s))
88 continue;
89
90 ret = memcg_update_cache_size(s, num_memcgs);
91 /*
92 * See comment in memcontrol.c, memcg_update_cache_size:
93 * Instead of freeing the memory, we'll just leave the caches
94 * up to this point in an updated state.
95 */
96 if (ret)
97 goto out;
98 }
99
100 memcg_update_array_size(num_memcgs);
101out:
102 mutex_unlock(&slab_mutex);
103 return ret;
104}
105#endif
106
45906855
CL
107/*
108 * Figure out what the alignment of the objects will be given a set of
109 * flags, a user specified alignment and the size of the objects.
110 */
111unsigned long calculate_alignment(unsigned long flags,
112 unsigned long align, unsigned long size)
113{
114 /*
115 * If the user wants hardware cache aligned objects then follow that
116 * suggestion if the object is sufficiently large.
117 *
118 * The hardware cache alignment cannot override the specified
119 * alignment though. If that is greater then use it.
120 */
121 if (flags & SLAB_HWCACHE_ALIGN) {
122 unsigned long ralign = cache_line_size();
123 while (size <= ralign / 2)
124 ralign /= 2;
125 align = max(align, ralign);
126 }
127
128 if (align < ARCH_SLAB_MINALIGN)
129 align = ARCH_SLAB_MINALIGN;
130
131 return ALIGN(align, sizeof(void *));
132}
133
794b1248
VD
134static struct kmem_cache *
135do_kmem_cache_create(char *name, size_t object_size, size_t size, size_t align,
136 unsigned long flags, void (*ctor)(void *),
137 struct mem_cgroup *memcg, struct kmem_cache *root_cache)
138{
139 struct kmem_cache *s;
140 int err;
141
142 err = -ENOMEM;
143 s = kmem_cache_zalloc(kmem_cache, GFP_KERNEL);
144 if (!s)
145 goto out;
146
147 s->name = name;
148 s->object_size = object_size;
149 s->size = size;
150 s->align = align;
151 s->ctor = ctor;
152
153 err = memcg_alloc_cache_params(memcg, s, root_cache);
154 if (err)
155 goto out_free_cache;
156
157 err = __kmem_cache_create(s, flags);
158 if (err)
159 goto out_free_cache;
160
161 s->refcount = 1;
162 list_add(&s->list, &slab_caches);
163 memcg_register_cache(s);
164out:
165 if (err)
166 return ERR_PTR(err);
167 return s;
168
169out_free_cache:
170 memcg_free_cache_params(s);
171 kfree(s);
172 goto out;
173}
45906855 174
77be4b13
SK
175/*
176 * kmem_cache_create - Create a cache.
177 * @name: A string which is used in /proc/slabinfo to identify this cache.
178 * @size: The size of objects to be created in this cache.
179 * @align: The required alignment for the objects.
180 * @flags: SLAB flags
181 * @ctor: A constructor for the objects.
182 *
183 * Returns a ptr to the cache on success, NULL on failure.
184 * Cannot be called within a interrupt, but can be interrupted.
185 * The @ctor is run when new pages are allocated by the cache.
186 *
187 * The flags are
188 *
189 * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5)
190 * to catch references to uninitialised memory.
191 *
192 * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check
193 * for buffer overruns.
194 *
195 * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware
196 * cacheline. This can be beneficial if you're counting cycles as closely
197 * as davem.
198 */
2633d7a0 199struct kmem_cache *
794b1248
VD
200kmem_cache_create(const char *name, size_t size, size_t align,
201 unsigned long flags, void (*ctor)(void *))
77be4b13 202{
794b1248
VD
203 struct kmem_cache *s;
204 char *cache_name;
3965fc36 205 int err;
039363f3 206
77be4b13
SK
207 get_online_cpus();
208 mutex_lock(&slab_mutex);
686d550d 209
794b1248 210 err = kmem_cache_sanity_check(name, size);
3965fc36
VD
211 if (err)
212 goto out_unlock;
686d550d 213
d8843922
GC
214 /*
215 * Some allocators will constraint the set of valid flags to a subset
216 * of all flags. We expect them to define CACHE_CREATE_MASK in this
217 * case, and we'll just provide them with a sanitized version of the
218 * passed flags.
219 */
220 flags &= CACHE_CREATE_MASK;
686d550d 221
794b1248
VD
222 s = __kmem_cache_alias(name, size, align, flags, ctor);
223 if (s)
3965fc36 224 goto out_unlock;
2633d7a0 225
794b1248
VD
226 cache_name = kstrdup(name, GFP_KERNEL);
227 if (!cache_name) {
228 err = -ENOMEM;
229 goto out_unlock;
230 }
7c9adf5a 231
794b1248
VD
232 s = do_kmem_cache_create(cache_name, size, size,
233 calculate_alignment(flags, align, size),
234 flags, ctor, NULL, NULL);
235 if (IS_ERR(s)) {
236 err = PTR_ERR(s);
237 kfree(cache_name);
238 }
3965fc36
VD
239
240out_unlock:
20cea968
CL
241 mutex_unlock(&slab_mutex);
242 put_online_cpus();
243
ba3253c7 244 if (err) {
686d550d
CL
245 if (flags & SLAB_PANIC)
246 panic("kmem_cache_create: Failed to create slab '%s'. Error %d\n",
247 name, err);
248 else {
249 printk(KERN_WARNING "kmem_cache_create(%s) failed with error %d",
250 name, err);
251 dump_stack();
252 }
686d550d
CL
253 return NULL;
254 }
039363f3
CL
255 return s;
256}
794b1248 257EXPORT_SYMBOL(kmem_cache_create);
2633d7a0 258
794b1248
VD
259#ifdef CONFIG_MEMCG_KMEM
260/*
261 * kmem_cache_create_memcg - Create a cache for a memory cgroup.
262 * @memcg: The memory cgroup the new cache is for.
263 * @root_cache: The parent of the new cache.
264 *
265 * This function attempts to create a kmem cache that will serve allocation
266 * requests going from @memcg to @root_cache. The new cache inherits properties
267 * from its parent.
268 */
269void kmem_cache_create_memcg(struct mem_cgroup *memcg, struct kmem_cache *root_cache)
2633d7a0 270{
794b1248
VD
271 struct kmem_cache *s;
272 char *cache_name;
273
274 get_online_cpus();
275 mutex_lock(&slab_mutex);
276
277 /*
278 * Since per-memcg caches are created asynchronously on first
279 * allocation (see memcg_kmem_get_cache()), several threads can try to
280 * create the same cache, but only one of them may succeed.
281 */
282 if (cache_from_memcg_idx(root_cache, memcg_cache_id(memcg)))
283 goto out_unlock;
284
285 cache_name = memcg_create_cache_name(memcg, root_cache);
286 if (!cache_name)
287 goto out_unlock;
288
289 s = do_kmem_cache_create(cache_name, root_cache->object_size,
290 root_cache->size, root_cache->align,
291 root_cache->flags, root_cache->ctor,
292 memcg, root_cache);
293 if (IS_ERR(s)) {
294 kfree(cache_name);
295 goto out_unlock;
296 }
297
298 s->allocflags |= __GFP_KMEMCG;
299
300out_unlock:
301 mutex_unlock(&slab_mutex);
302 put_online_cpus();
2633d7a0 303}
794b1248 304#endif /* CONFIG_MEMCG_KMEM */
97d06609 305
945cf2b6
CL
306void kmem_cache_destroy(struct kmem_cache *s)
307{
7cf27982
GC
308 /* Destroy all the children caches if we aren't a memcg cache */
309 kmem_cache_destroy_memcg_children(s);
310
945cf2b6
CL
311 get_online_cpus();
312 mutex_lock(&slab_mutex);
313 s->refcount--;
314 if (!s->refcount) {
315 list_del(&s->list);
051dd460 316 memcg_unregister_cache(s);
945cf2b6
CL
317
318 if (!__kmem_cache_shutdown(s)) {
210ed9de 319 mutex_unlock(&slab_mutex);
945cf2b6
CL
320 if (s->flags & SLAB_DESTROY_BY_RCU)
321 rcu_barrier();
322
1aa13254 323 memcg_free_cache_params(s);
db265eca 324 kfree(s->name);
8f4c765c 325 kmem_cache_free(kmem_cache, s);
945cf2b6
CL
326 } else {
327 list_add(&s->list, &slab_caches);
051dd460 328 memcg_register_cache(s);
210ed9de 329 mutex_unlock(&slab_mutex);
945cf2b6
CL
330 printk(KERN_ERR "kmem_cache_destroy %s: Slab cache still has objects\n",
331 s->name);
332 dump_stack();
333 }
210ed9de
JK
334 } else {
335 mutex_unlock(&slab_mutex);
945cf2b6 336 }
945cf2b6
CL
337 put_online_cpus();
338}
339EXPORT_SYMBOL(kmem_cache_destroy);
340
97d06609
CL
341int slab_is_available(void)
342{
343 return slab_state >= UP;
344}
b7454ad3 345
45530c44
CL
346#ifndef CONFIG_SLOB
347/* Create a cache during boot when no slab services are available yet */
348void __init create_boot_cache(struct kmem_cache *s, const char *name, size_t size,
349 unsigned long flags)
350{
351 int err;
352
353 s->name = name;
354 s->size = s->object_size = size;
45906855 355 s->align = calculate_alignment(flags, ARCH_KMALLOC_MINALIGN, size);
45530c44
CL
356 err = __kmem_cache_create(s, flags);
357
358 if (err)
31ba7346 359 panic("Creation of kmalloc slab %s size=%zu failed. Reason %d\n",
45530c44
CL
360 name, size, err);
361
362 s->refcount = -1; /* Exempt from merging for now */
363}
364
365struct kmem_cache *__init create_kmalloc_cache(const char *name, size_t size,
366 unsigned long flags)
367{
368 struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT);
369
370 if (!s)
371 panic("Out of memory when creating slab %s\n", name);
372
373 create_boot_cache(s, name, size, flags);
374 list_add(&s->list, &slab_caches);
375 s->refcount = 1;
376 return s;
377}
378
9425c58e
CL
379struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
380EXPORT_SYMBOL(kmalloc_caches);
381
382#ifdef CONFIG_ZONE_DMA
383struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
384EXPORT_SYMBOL(kmalloc_dma_caches);
385#endif
386
2c59dd65
CL
387/*
388 * Conversion table for small slabs sizes / 8 to the index in the
389 * kmalloc array. This is necessary for slabs < 192 since we have non power
390 * of two cache sizes there. The size of larger slabs can be determined using
391 * fls.
392 */
393static s8 size_index[24] = {
394 3, /* 8 */
395 4, /* 16 */
396 5, /* 24 */
397 5, /* 32 */
398 6, /* 40 */
399 6, /* 48 */
400 6, /* 56 */
401 6, /* 64 */
402 1, /* 72 */
403 1, /* 80 */
404 1, /* 88 */
405 1, /* 96 */
406 7, /* 104 */
407 7, /* 112 */
408 7, /* 120 */
409 7, /* 128 */
410 2, /* 136 */
411 2, /* 144 */
412 2, /* 152 */
413 2, /* 160 */
414 2, /* 168 */
415 2, /* 176 */
416 2, /* 184 */
417 2 /* 192 */
418};
419
420static inline int size_index_elem(size_t bytes)
421{
422 return (bytes - 1) / 8;
423}
424
425/*
426 * Find the kmem_cache structure that serves a given size of
427 * allocation
428 */
429struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags)
430{
431 int index;
432
9de1bc87 433 if (unlikely(size > KMALLOC_MAX_SIZE)) {
907985f4 434 WARN_ON_ONCE(!(flags & __GFP_NOWARN));
6286ae97 435 return NULL;
907985f4 436 }
6286ae97 437
2c59dd65
CL
438 if (size <= 192) {
439 if (!size)
440 return ZERO_SIZE_PTR;
441
442 index = size_index[size_index_elem(size)];
443 } else
444 index = fls(size - 1);
445
446#ifdef CONFIG_ZONE_DMA
b1e05416 447 if (unlikely((flags & GFP_DMA)))
2c59dd65
CL
448 return kmalloc_dma_caches[index];
449
450#endif
451 return kmalloc_caches[index];
452}
453
f97d5f63
CL
454/*
455 * Create the kmalloc array. Some of the regular kmalloc arrays
456 * may already have been created because they were needed to
457 * enable allocations for slab creation.
458 */
459void __init create_kmalloc_caches(unsigned long flags)
460{
461 int i;
462
2c59dd65
CL
463 /*
464 * Patch up the size_index table if we have strange large alignment
465 * requirements for the kmalloc array. This is only the case for
466 * MIPS it seems. The standard arches will not generate any code here.
467 *
468 * Largest permitted alignment is 256 bytes due to the way we
469 * handle the index determination for the smaller caches.
470 *
471 * Make sure that nothing crazy happens if someone starts tinkering
472 * around with ARCH_KMALLOC_MINALIGN
473 */
474 BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 ||
475 (KMALLOC_MIN_SIZE & (KMALLOC_MIN_SIZE - 1)));
476
477 for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) {
478 int elem = size_index_elem(i);
479
480 if (elem >= ARRAY_SIZE(size_index))
481 break;
482 size_index[elem] = KMALLOC_SHIFT_LOW;
483 }
484
485 if (KMALLOC_MIN_SIZE >= 64) {
486 /*
487 * The 96 byte size cache is not used if the alignment
488 * is 64 byte.
489 */
490 for (i = 64 + 8; i <= 96; i += 8)
491 size_index[size_index_elem(i)] = 7;
492
493 }
494
495 if (KMALLOC_MIN_SIZE >= 128) {
496 /*
497 * The 192 byte sized cache is not used if the alignment
498 * is 128 byte. Redirect kmalloc to use the 256 byte cache
499 * instead.
500 */
501 for (i = 128 + 8; i <= 192; i += 8)
502 size_index[size_index_elem(i)] = 8;
503 }
8a965b3b
CL
504 for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) {
505 if (!kmalloc_caches[i]) {
f97d5f63
CL
506 kmalloc_caches[i] = create_kmalloc_cache(NULL,
507 1 << i, flags);
956e46ef 508 }
f97d5f63 509
956e46ef
CM
510 /*
511 * Caches that are not of the two-to-the-power-of size.
512 * These have to be created immediately after the
513 * earlier power of two caches
514 */
515 if (KMALLOC_MIN_SIZE <= 32 && !kmalloc_caches[1] && i == 6)
516 kmalloc_caches[1] = create_kmalloc_cache(NULL, 96, flags);
8a965b3b 517
956e46ef
CM
518 if (KMALLOC_MIN_SIZE <= 64 && !kmalloc_caches[2] && i == 7)
519 kmalloc_caches[2] = create_kmalloc_cache(NULL, 192, flags);
8a965b3b
CL
520 }
521
f97d5f63
CL
522 /* Kmalloc array is now usable */
523 slab_state = UP;
524
525 for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) {
526 struct kmem_cache *s = kmalloc_caches[i];
527 char *n;
528
529 if (s) {
530 n = kasprintf(GFP_NOWAIT, "kmalloc-%d", kmalloc_size(i));
531
532 BUG_ON(!n);
533 s->name = n;
534 }
535 }
536
537#ifdef CONFIG_ZONE_DMA
538 for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) {
539 struct kmem_cache *s = kmalloc_caches[i];
540
541 if (s) {
542 int size = kmalloc_size(i);
543 char *n = kasprintf(GFP_NOWAIT,
544 "dma-kmalloc-%d", size);
545
546 BUG_ON(!n);
547 kmalloc_dma_caches[i] = create_kmalloc_cache(n,
548 size, SLAB_CACHE_DMA | flags);
549 }
550 }
551#endif
552}
45530c44
CL
553#endif /* !CONFIG_SLOB */
554
f1b6eb6e
CL
555#ifdef CONFIG_TRACING
556void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
557{
558 void *ret = kmalloc_order(size, flags, order);
559 trace_kmalloc(_RET_IP_, ret, size, PAGE_SIZE << order, flags);
560 return ret;
561}
562EXPORT_SYMBOL(kmalloc_order_trace);
563#endif
45530c44 564
b7454ad3 565#ifdef CONFIG_SLABINFO
e9b4db2b
WL
566
567#ifdef CONFIG_SLAB
568#define SLABINFO_RIGHTS (S_IWUSR | S_IRUSR)
569#else
570#define SLABINFO_RIGHTS S_IRUSR
571#endif
572
749c5415 573void print_slabinfo_header(struct seq_file *m)
bcee6e2a
GC
574{
575 /*
576 * Output format version, so at least we can change it
577 * without _too_ many complaints.
578 */
579#ifdef CONFIG_DEBUG_SLAB
580 seq_puts(m, "slabinfo - version: 2.1 (statistics)\n");
581#else
582 seq_puts(m, "slabinfo - version: 2.1\n");
583#endif
584 seq_puts(m, "# name <active_objs> <num_objs> <objsize> "
585 "<objperslab> <pagesperslab>");
586 seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
587 seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
588#ifdef CONFIG_DEBUG_SLAB
589 seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> "
590 "<error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>");
591 seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>");
592#endif
593 seq_putc(m, '\n');
594}
595
b7454ad3
GC
596static void *s_start(struct seq_file *m, loff_t *pos)
597{
598 loff_t n = *pos;
599
600 mutex_lock(&slab_mutex);
601 if (!n)
602 print_slabinfo_header(m);
603
604 return seq_list_start(&slab_caches, *pos);
605}
606
276a2439 607void *slab_next(struct seq_file *m, void *p, loff_t *pos)
b7454ad3
GC
608{
609 return seq_list_next(p, &slab_caches, pos);
610}
611
276a2439 612void slab_stop(struct seq_file *m, void *p)
b7454ad3
GC
613{
614 mutex_unlock(&slab_mutex);
615}
616
749c5415
GC
617static void
618memcg_accumulate_slabinfo(struct kmem_cache *s, struct slabinfo *info)
619{
620 struct kmem_cache *c;
621 struct slabinfo sinfo;
622 int i;
623
624 if (!is_root_cache(s))
625 return;
626
627 for_each_memcg_cache_index(i) {
2ade4de8 628 c = cache_from_memcg_idx(s, i);
749c5415
GC
629 if (!c)
630 continue;
631
632 memset(&sinfo, 0, sizeof(sinfo));
633 get_slabinfo(c, &sinfo);
634
635 info->active_slabs += sinfo.active_slabs;
636 info->num_slabs += sinfo.num_slabs;
637 info->shared_avail += sinfo.shared_avail;
638 info->active_objs += sinfo.active_objs;
639 info->num_objs += sinfo.num_objs;
640 }
641}
642
643int cache_show(struct kmem_cache *s, struct seq_file *m)
b7454ad3 644{
0d7561c6
GC
645 struct slabinfo sinfo;
646
647 memset(&sinfo, 0, sizeof(sinfo));
648 get_slabinfo(s, &sinfo);
649
749c5415
GC
650 memcg_accumulate_slabinfo(s, &sinfo);
651
0d7561c6 652 seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d",
749c5415 653 cache_name(s), sinfo.active_objs, sinfo.num_objs, s->size,
0d7561c6
GC
654 sinfo.objects_per_slab, (1 << sinfo.cache_order));
655
656 seq_printf(m, " : tunables %4u %4u %4u",
657 sinfo.limit, sinfo.batchcount, sinfo.shared);
658 seq_printf(m, " : slabdata %6lu %6lu %6lu",
659 sinfo.active_slabs, sinfo.num_slabs, sinfo.shared_avail);
660 slabinfo_show_stats(m, s);
661 seq_putc(m, '\n');
662 return 0;
b7454ad3
GC
663}
664
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665static int s_show(struct seq_file *m, void *p)
666{
667 struct kmem_cache *s = list_entry(p, struct kmem_cache, list);
668
669 if (!is_root_cache(s))
670 return 0;
671 return cache_show(s, m);
672}
673
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674/*
675 * slabinfo_op - iterator that generates /proc/slabinfo
676 *
677 * Output layout:
678 * cache-name
679 * num-active-objs
680 * total-objs
681 * object size
682 * num-active-slabs
683 * total-slabs
684 * num-pages-per-slab
685 * + further values on SMP and with statistics enabled
686 */
687static const struct seq_operations slabinfo_op = {
688 .start = s_start,
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689 .next = slab_next,
690 .stop = slab_stop,
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691 .show = s_show,
692};
693
694static int slabinfo_open(struct inode *inode, struct file *file)
695{
696 return seq_open(file, &slabinfo_op);
697}
698
699static const struct file_operations proc_slabinfo_operations = {
700 .open = slabinfo_open,
701 .read = seq_read,
702 .write = slabinfo_write,
703 .llseek = seq_lseek,
704 .release = seq_release,
705};
706
707static int __init slab_proc_init(void)
708{
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709 proc_create("slabinfo", SLABINFO_RIGHTS, NULL,
710 &proc_slabinfo_operations);
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711 return 0;
712}
713module_init(slab_proc_init);
714#endif /* CONFIG_SLABINFO */