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Christoph Lameter039363f2012-07-06 15:25:10 -05001/*
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>
Christoph Lameter20cea962012-07-06 15:25:13 -050014#include <linux/cpu.h>
15#include <linux/uaccess.h>
Glauber Costab7454ad2012-10-19 18:20:25 +040016#include <linux/seq_file.h>
17#include <linux/proc_fs.h>
Christoph Lameter039363f2012-07-06 15:25:10 -050018#include <asm/cacheflush.h>
19#include <asm/tlbflush.h>
20#include <asm/page.h>
Glauber Costa2633d7a2012-12-18 14:22:34 -080021#include <linux/memcontrol.h>
Andrey Ryabinin928cec92014-08-06 16:04:44 -070022
23#define CREATE_TRACE_POINTS
Christoph Lameterf1b6eb62013-09-04 16:35:34 +000024#include <trace/events/kmem.h>
Christoph Lameter039363f2012-07-06 15:25:10 -050025
Christoph Lameter97d06602012-07-06 15:25:11 -050026#include "slab.h"
27
28enum slab_state slab_state;
Christoph Lameter18004c52012-07-06 15:25:12 -050029LIST_HEAD(slab_caches);
30DEFINE_MUTEX(slab_mutex);
Christoph Lameter9b030cb2012-09-05 00:20:33 +000031struct kmem_cache *kmem_cache;
Christoph Lameter97d06602012-07-06 15:25:11 -050032
Joonsoo Kim07f361b2014-10-09 15:26:00 -070033/*
Joonsoo Kim423c9292014-10-09 15:26:22 -070034 * Set of flags that will prevent slab merging
35 */
36#define SLAB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
37 SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \
38 SLAB_FAILSLAB)
39
Konstantin Khlebnikov3e810ae2015-08-06 15:46:36 -070040#define SLAB_MERGE_SAME (SLAB_RECLAIM_ACCOUNT | SLAB_CACHE_DMA | SLAB_NOTRACK)
Joonsoo Kim423c9292014-10-09 15:26:22 -070041
42/*
43 * Merge control. If this is set then no merging of slab caches will occur.
44 * (Could be removed. This was introduced to pacify the merge skeptics.)
45 */
46static int slab_nomerge;
47
48static int __init setup_slab_nomerge(char *str)
49{
50 slab_nomerge = 1;
51 return 1;
52}
53
54#ifdef CONFIG_SLUB
55__setup_param("slub_nomerge", slub_nomerge, setup_slab_nomerge, 0);
56#endif
57
58__setup("slab_nomerge", setup_slab_nomerge);
59
60/*
Joonsoo Kim07f361b2014-10-09 15:26:00 -070061 * Determine the size of a slab object
62 */
63unsigned int kmem_cache_size(struct kmem_cache *s)
64{
65 return s->object_size;
66}
67EXPORT_SYMBOL(kmem_cache_size);
68
Shuah Khan77be4b12012-08-16 00:09:46 -070069#ifdef CONFIG_DEBUG_VM
Vladimir Davydov794b1242014-04-07 15:39:26 -070070static int kmem_cache_sanity_check(const char *name, size_t size)
Shuah Khan77be4b12012-08-16 00:09:46 -070071{
72 struct kmem_cache *s = NULL;
73
74 if (!name || in_interrupt() || size < sizeof(void *) ||
75 size > KMALLOC_MAX_SIZE) {
76 pr_err("kmem_cache_create(%s) integrity check failed\n", name);
77 return -EINVAL;
78 }
79
80 list_for_each_entry(s, &slab_caches, list) {
81 char tmp;
82 int res;
83
84 /*
85 * This happens when the module gets unloaded and doesn't
86 * destroy its slab cache and no-one else reuses the vmalloc
87 * area of the module. Print a warning.
88 */
89 res = probe_kernel_address(s->name, tmp);
90 if (res) {
91 pr_err("Slab cache with size %d has lost its name\n",
92 s->object_size);
93 continue;
94 }
Shuah Khan77be4b12012-08-16 00:09:46 -070095 }
96
97 WARN_ON(strchr(name, ' ')); /* It confuses parsers */
98 return 0;
99}
100#else
Vladimir Davydov794b1242014-04-07 15:39:26 -0700101static inline int kmem_cache_sanity_check(const char *name, size_t size)
Shuah Khan77be4b12012-08-16 00:09:46 -0700102{
103 return 0;
104}
105#endif
106
Christoph Lameter484748f2015-09-04 15:45:34 -0700107void __kmem_cache_free_bulk(struct kmem_cache *s, size_t nr, void **p)
108{
109 size_t i;
110
111 for (i = 0; i < nr; i++)
112 kmem_cache_free(s, p[i]);
113}
114
115bool __kmem_cache_alloc_bulk(struct kmem_cache *s, gfp_t flags, size_t nr,
116 void **p)
117{
118 size_t i;
119
120 for (i = 0; i < nr; i++) {
121 void *x = p[i] = kmem_cache_alloc(s, flags);
122 if (!x) {
123 __kmem_cache_free_bulk(s, i, p);
124 return false;
125 }
126 }
127 return true;
128}
129
Glauber Costa55007d82012-12-18 14:22:38 -0800130#ifdef CONFIG_MEMCG_KMEM
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800131void slab_init_memcg_params(struct kmem_cache *s)
Vladimir Davydov33a690c2014-10-09 15:28:43 -0700132{
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800133 s->memcg_params.is_root_cache = true;
Vladimir Davydov426589f2015-02-12 14:59:23 -0800134 INIT_LIST_HEAD(&s->memcg_params.list);
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800135 RCU_INIT_POINTER(s->memcg_params.memcg_caches, NULL);
136}
Vladimir Davydov33a690c2014-10-09 15:28:43 -0700137
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800138static int init_memcg_params(struct kmem_cache *s,
139 struct mem_cgroup *memcg, struct kmem_cache *root_cache)
140{
141 struct memcg_cache_array *arr;
Vladimir Davydov33a690c2014-10-09 15:28:43 -0700142
143 if (memcg) {
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800144 s->memcg_params.is_root_cache = false;
145 s->memcg_params.memcg = memcg;
146 s->memcg_params.root_cache = root_cache;
147 return 0;
148 }
Vladimir Davydov33a690c2014-10-09 15:28:43 -0700149
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800150 slab_init_memcg_params(s);
151
152 if (!memcg_nr_cache_ids)
153 return 0;
154
155 arr = kzalloc(sizeof(struct memcg_cache_array) +
156 memcg_nr_cache_ids * sizeof(void *),
157 GFP_KERNEL);
158 if (!arr)
159 return -ENOMEM;
160
161 RCU_INIT_POINTER(s->memcg_params.memcg_caches, arr);
Vladimir Davydov33a690c2014-10-09 15:28:43 -0700162 return 0;
163}
164
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800165static void destroy_memcg_params(struct kmem_cache *s)
Vladimir Davydov33a690c2014-10-09 15:28:43 -0700166{
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800167 if (is_root_cache(s))
168 kfree(rcu_access_pointer(s->memcg_params.memcg_caches));
Vladimir Davydov33a690c2014-10-09 15:28:43 -0700169}
170
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800171static int update_memcg_params(struct kmem_cache *s, int new_array_size)
Vladimir Davydov6f817f42014-10-09 15:28:47 -0700172{
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800173 struct memcg_cache_array *old, *new;
Vladimir Davydov6f817f42014-10-09 15:28:47 -0700174
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800175 if (!is_root_cache(s))
176 return 0;
Vladimir Davydov6f817f42014-10-09 15:28:47 -0700177
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800178 new = kzalloc(sizeof(struct memcg_cache_array) +
179 new_array_size * sizeof(void *), GFP_KERNEL);
180 if (!new)
Vladimir Davydov6f817f42014-10-09 15:28:47 -0700181 return -ENOMEM;
182
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800183 old = rcu_dereference_protected(s->memcg_params.memcg_caches,
184 lockdep_is_held(&slab_mutex));
185 if (old)
186 memcpy(new->entries, old->entries,
187 memcg_nr_cache_ids * sizeof(void *));
Vladimir Davydov6f817f42014-10-09 15:28:47 -0700188
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800189 rcu_assign_pointer(s->memcg_params.memcg_caches, new);
190 if (old)
191 kfree_rcu(old, rcu);
Vladimir Davydov6f817f42014-10-09 15:28:47 -0700192 return 0;
193}
194
Glauber Costa55007d82012-12-18 14:22:38 -0800195int memcg_update_all_caches(int num_memcgs)
196{
197 struct kmem_cache *s;
198 int ret = 0;
Glauber Costa55007d82012-12-18 14:22:38 -0800199
Vladimir Davydov05257a12015-02-12 14:59:01 -0800200 mutex_lock(&slab_mutex);
Glauber Costa55007d82012-12-18 14:22:38 -0800201 list_for_each_entry(s, &slab_caches, list) {
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800202 ret = update_memcg_params(s, num_memcgs);
Glauber Costa55007d82012-12-18 14:22:38 -0800203 /*
Glauber Costa55007d82012-12-18 14:22:38 -0800204 * Instead of freeing the memory, we'll just leave the caches
205 * up to this point in an updated state.
206 */
207 if (ret)
Vladimir Davydov05257a12015-02-12 14:59:01 -0800208 break;
Glauber Costa55007d82012-12-18 14:22:38 -0800209 }
Glauber Costa55007d82012-12-18 14:22:38 -0800210 mutex_unlock(&slab_mutex);
211 return ret;
212}
Vladimir Davydov33a690c2014-10-09 15:28:43 -0700213#else
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800214static inline int init_memcg_params(struct kmem_cache *s,
215 struct mem_cgroup *memcg, struct kmem_cache *root_cache)
Vladimir Davydov33a690c2014-10-09 15:28:43 -0700216{
217 return 0;
218}
219
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800220static inline void destroy_memcg_params(struct kmem_cache *s)
Vladimir Davydov33a690c2014-10-09 15:28:43 -0700221{
222}
223#endif /* CONFIG_MEMCG_KMEM */
Glauber Costa55007d82012-12-18 14:22:38 -0800224
Christoph Lameter039363f2012-07-06 15:25:10 -0500225/*
Joonsoo Kim423c9292014-10-09 15:26:22 -0700226 * Find a mergeable slab cache
227 */
228int slab_unmergeable(struct kmem_cache *s)
229{
230 if (slab_nomerge || (s->flags & SLAB_NEVER_MERGE))
231 return 1;
232
233 if (!is_root_cache(s))
234 return 1;
235
236 if (s->ctor)
237 return 1;
238
239 /*
240 * We may have set a slab to be unmergeable during bootstrap.
241 */
242 if (s->refcount < 0)
243 return 1;
244
245 return 0;
246}
247
248struct kmem_cache *find_mergeable(size_t size, size_t align,
249 unsigned long flags, const char *name, void (*ctor)(void *))
250{
251 struct kmem_cache *s;
252
253 if (slab_nomerge || (flags & SLAB_NEVER_MERGE))
254 return NULL;
255
256 if (ctor)
257 return NULL;
258
259 size = ALIGN(size, sizeof(void *));
260 align = calculate_alignment(flags, align, size);
261 size = ALIGN(size, align);
262 flags = kmem_cache_flags(size, flags, name, NULL);
263
Joonsoo Kim54362052014-12-10 15:42:18 -0800264 list_for_each_entry_reverse(s, &slab_caches, list) {
Joonsoo Kim423c9292014-10-09 15:26:22 -0700265 if (slab_unmergeable(s))
266 continue;
267
268 if (size > s->size)
269 continue;
270
271 if ((flags & SLAB_MERGE_SAME) != (s->flags & SLAB_MERGE_SAME))
272 continue;
273 /*
274 * Check if alignment is compatible.
275 * Courtesy of Adrian Drzewiecki
276 */
277 if ((s->size & ~(align - 1)) != s->size)
278 continue;
279
280 if (s->size - size >= sizeof(void *))
281 continue;
282
Joonsoo Kim95069ac82014-11-13 15:19:25 -0800283 if (IS_ENABLED(CONFIG_SLAB) && align &&
284 (align > s->align || s->align % align))
285 continue;
286
Joonsoo Kim423c9292014-10-09 15:26:22 -0700287 return s;
288 }
289 return NULL;
290}
291
292/*
Christoph Lameter45906852012-11-28 16:23:16 +0000293 * Figure out what the alignment of the objects will be given a set of
294 * flags, a user specified alignment and the size of the objects.
295 */
296unsigned long calculate_alignment(unsigned long flags,
297 unsigned long align, unsigned long size)
298{
299 /*
300 * If the user wants hardware cache aligned objects then follow that
301 * suggestion if the object is sufficiently large.
302 *
303 * The hardware cache alignment cannot override the specified
304 * alignment though. If that is greater then use it.
305 */
306 if (flags & SLAB_HWCACHE_ALIGN) {
307 unsigned long ralign = cache_line_size();
308 while (size <= ralign / 2)
309 ralign /= 2;
310 align = max(align, ralign);
311 }
312
313 if (align < ARCH_SLAB_MINALIGN)
314 align = ARCH_SLAB_MINALIGN;
315
316 return ALIGN(align, sizeof(void *));
317}
318
Vladimir Davydov794b1242014-04-07 15:39:26 -0700319static struct kmem_cache *
Andrzej Hajda3dec16e2015-02-13 14:36:38 -0800320do_kmem_cache_create(const char *name, size_t object_size, size_t size,
321 size_t align, unsigned long flags, void (*ctor)(void *),
Vladimir Davydov794b1242014-04-07 15:39:26 -0700322 struct mem_cgroup *memcg, struct kmem_cache *root_cache)
323{
324 struct kmem_cache *s;
325 int err;
326
327 err = -ENOMEM;
328 s = kmem_cache_zalloc(kmem_cache, GFP_KERNEL);
329 if (!s)
330 goto out;
331
332 s->name = name;
333 s->object_size = object_size;
334 s->size = size;
335 s->align = align;
336 s->ctor = ctor;
337
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800338 err = init_memcg_params(s, memcg, root_cache);
Vladimir Davydov794b1242014-04-07 15:39:26 -0700339 if (err)
340 goto out_free_cache;
341
342 err = __kmem_cache_create(s, flags);
343 if (err)
344 goto out_free_cache;
345
346 s->refcount = 1;
347 list_add(&s->list, &slab_caches);
Vladimir Davydov794b1242014-04-07 15:39:26 -0700348out:
349 if (err)
350 return ERR_PTR(err);
351 return s;
352
353out_free_cache:
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800354 destroy_memcg_params(s);
Vaishali Thakkar7c4da062015-02-10 14:09:40 -0800355 kmem_cache_free(kmem_cache, s);
Vladimir Davydov794b1242014-04-07 15:39:26 -0700356 goto out;
357}
Christoph Lameter45906852012-11-28 16:23:16 +0000358
359/*
Christoph Lameter039363f2012-07-06 15:25:10 -0500360 * kmem_cache_create - Create a cache.
361 * @name: A string which is used in /proc/slabinfo to identify this cache.
362 * @size: The size of objects to be created in this cache.
363 * @align: The required alignment for the objects.
364 * @flags: SLAB flags
365 * @ctor: A constructor for the objects.
366 *
367 * Returns a ptr to the cache on success, NULL on failure.
368 * Cannot be called within a interrupt, but can be interrupted.
369 * The @ctor is run when new pages are allocated by the cache.
370 *
371 * The flags are
372 *
373 * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5)
374 * to catch references to uninitialised memory.
375 *
376 * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check
377 * for buffer overruns.
378 *
379 * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware
380 * cacheline. This can be beneficial if you're counting cycles as closely
381 * as davem.
382 */
Glauber Costa2633d7a2012-12-18 14:22:34 -0800383struct kmem_cache *
Vladimir Davydov794b1242014-04-07 15:39:26 -0700384kmem_cache_create(const char *name, size_t size, size_t align,
385 unsigned long flags, void (*ctor)(void *))
Christoph Lameter039363f2012-07-06 15:25:10 -0500386{
Vladimir Davydov794b1242014-04-07 15:39:26 -0700387 struct kmem_cache *s;
Andrzej Hajda3dec16e2015-02-13 14:36:38 -0800388 const char *cache_name;
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800389 int err;
Christoph Lameter039363f2012-07-06 15:25:10 -0500390
Pekka Enbergb9205362012-08-16 10:12:18 +0300391 get_online_cpus();
Vladimir Davydov03afc0e2014-06-04 16:07:20 -0700392 get_online_mems();
Vladimir Davydov05257a12015-02-12 14:59:01 -0800393 memcg_get_cache_ids();
Vladimir Davydov03afc0e2014-06-04 16:07:20 -0700394
Pekka Enbergb9205362012-08-16 10:12:18 +0300395 mutex_lock(&slab_mutex);
Christoph Lameter686d5502012-09-05 00:20:33 +0000396
Vladimir Davydov794b1242014-04-07 15:39:26 -0700397 err = kmem_cache_sanity_check(name, size);
Andrew Morton3aa24f52014-10-09 15:25:58 -0700398 if (err) {
399 s = NULL; /* suppress uninit var warning */
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800400 goto out_unlock;
Andrew Morton3aa24f52014-10-09 15:25:58 -0700401 }
Christoph Lameter686d5502012-09-05 00:20:33 +0000402
Glauber Costad8843922012-10-17 15:36:51 +0400403 /*
404 * Some allocators will constraint the set of valid flags to a subset
405 * of all flags. We expect them to define CACHE_CREATE_MASK in this
406 * case, and we'll just provide them with a sanitized version of the
407 * passed flags.
408 */
409 flags &= CACHE_CREATE_MASK;
Christoph Lameter686d5502012-09-05 00:20:33 +0000410
Vladimir Davydov794b1242014-04-07 15:39:26 -0700411 s = __kmem_cache_alias(name, size, align, flags, ctor);
412 if (s)
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800413 goto out_unlock;
Glauber Costa2633d7a2012-12-18 14:22:34 -0800414
Andrzej Hajda3dec16e2015-02-13 14:36:38 -0800415 cache_name = kstrdup_const(name, GFP_KERNEL);
Vladimir Davydov794b1242014-04-07 15:39:26 -0700416 if (!cache_name) {
417 err = -ENOMEM;
418 goto out_unlock;
419 }
Glauber Costa2633d7a2012-12-18 14:22:34 -0800420
Vladimir Davydov794b1242014-04-07 15:39:26 -0700421 s = do_kmem_cache_create(cache_name, size, size,
422 calculate_alignment(flags, align, size),
423 flags, ctor, NULL, NULL);
424 if (IS_ERR(s)) {
425 err = PTR_ERR(s);
Andrzej Hajda3dec16e2015-02-13 14:36:38 -0800426 kfree_const(cache_name);
Vladimir Davydov794b1242014-04-07 15:39:26 -0700427 }
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800428
429out_unlock:
Christoph Lameter20cea962012-07-06 15:25:13 -0500430 mutex_unlock(&slab_mutex);
Vladimir Davydov03afc0e2014-06-04 16:07:20 -0700431
Vladimir Davydov05257a12015-02-12 14:59:01 -0800432 memcg_put_cache_ids();
Vladimir Davydov03afc0e2014-06-04 16:07:20 -0700433 put_online_mems();
Christoph Lameter20cea962012-07-06 15:25:13 -0500434 put_online_cpus();
435
Dave Jonesba3253c72014-01-29 14:05:48 -0800436 if (err) {
Christoph Lameter686d5502012-09-05 00:20:33 +0000437 if (flags & SLAB_PANIC)
438 panic("kmem_cache_create: Failed to create slab '%s'. Error %d\n",
439 name, err);
440 else {
441 printk(KERN_WARNING "kmem_cache_create(%s) failed with error %d",
442 name, err);
443 dump_stack();
444 }
Christoph Lameter686d5502012-09-05 00:20:33 +0000445 return NULL;
446 }
Christoph Lameter039363f2012-07-06 15:25:10 -0500447 return s;
Glauber Costa2633d7a2012-12-18 14:22:34 -0800448}
Christoph Lameter039363f2012-07-06 15:25:10 -0500449EXPORT_SYMBOL(kmem_cache_create);
Christoph Lameter97d06602012-07-06 15:25:11 -0500450
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800451static int do_kmem_cache_shutdown(struct kmem_cache *s,
452 struct list_head *release, bool *need_rcu_barrier)
453{
454 if (__kmem_cache_shutdown(s) != 0) {
455 printk(KERN_ERR "kmem_cache_destroy %s: "
456 "Slab cache still has objects\n", s->name);
457 dump_stack();
458 return -EBUSY;
459 }
460
461 if (s->flags & SLAB_DESTROY_BY_RCU)
462 *need_rcu_barrier = true;
463
464#ifdef CONFIG_MEMCG_KMEM
Vladimir Davydov2a4db7e2015-02-12 14:59:32 -0800465 if (!is_root_cache(s))
Vladimir Davydov426589f2015-02-12 14:59:23 -0800466 list_del(&s->memcg_params.list);
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800467#endif
468 list_move(&s->list, release);
469 return 0;
470}
471
472static void do_kmem_cache_release(struct list_head *release,
473 bool need_rcu_barrier)
474{
475 struct kmem_cache *s, *s2;
476
477 if (need_rcu_barrier)
478 rcu_barrier();
479
480 list_for_each_entry_safe(s, s2, release, list) {
481#ifdef SLAB_SUPPORTS_SYSFS
482 sysfs_slab_remove(s);
483#else
484 slab_kmem_cache_release(s);
485#endif
486 }
487}
488
Vladimir Davydov794b1242014-04-07 15:39:26 -0700489#ifdef CONFIG_MEMCG_KMEM
490/*
Vladimir Davydov776ed0f2014-06-04 16:10:02 -0700491 * memcg_create_kmem_cache - Create a cache for a memory cgroup.
Vladimir Davydov794b1242014-04-07 15:39:26 -0700492 * @memcg: The memory cgroup the new cache is for.
493 * @root_cache: The parent of the new cache.
494 *
495 * This function attempts to create a kmem cache that will serve allocation
496 * requests going from @memcg to @root_cache. The new cache inherits properties
497 * from its parent.
498 */
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800499void memcg_create_kmem_cache(struct mem_cgroup *memcg,
500 struct kmem_cache *root_cache)
Vladimir Davydov794b1242014-04-07 15:39:26 -0700501{
Vladimir Davydov3e0350a2015-02-10 14:11:44 -0800502 static char memcg_name_buf[NAME_MAX + 1]; /* protected by slab_mutex */
Michal Hocko33398cf2015-09-08 15:01:02 -0700503 struct cgroup_subsys_state *css = &memcg->css;
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800504 struct memcg_cache_array *arr;
Vladimir Davydovbd673142014-06-04 16:07:40 -0700505 struct kmem_cache *s = NULL;
Vladimir Davydov794b1242014-04-07 15:39:26 -0700506 char *cache_name;
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800507 int idx;
Vladimir Davydov794b1242014-04-07 15:39:26 -0700508
509 get_online_cpus();
Vladimir Davydov03afc0e2014-06-04 16:07:20 -0700510 get_online_mems();
511
Vladimir Davydov794b1242014-04-07 15:39:26 -0700512 mutex_lock(&slab_mutex);
513
Vladimir Davydov2a4db7e2015-02-12 14:59:32 -0800514 /*
515 * The memory cgroup could have been deactivated while the cache
516 * creation work was pending.
517 */
518 if (!memcg_kmem_is_active(memcg))
519 goto out_unlock;
520
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800521 idx = memcg_cache_id(memcg);
522 arr = rcu_dereference_protected(root_cache->memcg_params.memcg_caches,
523 lockdep_is_held(&slab_mutex));
524
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800525 /*
526 * Since per-memcg caches are created asynchronously on first
527 * allocation (see memcg_kmem_get_cache()), several threads can try to
528 * create the same cache, but only one of them may succeed.
529 */
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800530 if (arr->entries[idx])
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800531 goto out_unlock;
532
Vladimir Davydovf1008362015-02-12 14:59:29 -0800533 cgroup_name(css->cgroup, memcg_name_buf, sizeof(memcg_name_buf));
Vladimir Davydov073ee1c2014-06-04 16:08:23 -0700534 cache_name = kasprintf(GFP_KERNEL, "%s(%d:%s)", root_cache->name,
Vladimir Davydovf1008362015-02-12 14:59:29 -0800535 css->id, memcg_name_buf);
Vladimir Davydov794b1242014-04-07 15:39:26 -0700536 if (!cache_name)
537 goto out_unlock;
538
539 s = do_kmem_cache_create(cache_name, root_cache->object_size,
540 root_cache->size, root_cache->align,
541 root_cache->flags, root_cache->ctor,
542 memcg, root_cache);
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800543 /*
544 * If we could not create a memcg cache, do not complain, because
545 * that's not critical at all as we can always proceed with the root
546 * cache.
547 */
Vladimir Davydovbd673142014-06-04 16:07:40 -0700548 if (IS_ERR(s)) {
Vladimir Davydov794b1242014-04-07 15:39:26 -0700549 kfree(cache_name);
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800550 goto out_unlock;
Vladimir Davydovbd673142014-06-04 16:07:40 -0700551 }
Vladimir Davydov794b1242014-04-07 15:39:26 -0700552
Vladimir Davydov426589f2015-02-12 14:59:23 -0800553 list_add(&s->memcg_params.list, &root_cache->memcg_params.list);
554
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800555 /*
556 * Since readers won't lock (see cache_from_memcg_idx()), we need a
557 * barrier here to ensure nobody will see the kmem_cache partially
558 * initialized.
559 */
560 smp_wmb();
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800561 arr->entries[idx] = s;
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800562
Vladimir Davydov794b1242014-04-07 15:39:26 -0700563out_unlock:
564 mutex_unlock(&slab_mutex);
Vladimir Davydov03afc0e2014-06-04 16:07:20 -0700565
566 put_online_mems();
Vladimir Davydov794b1242014-04-07 15:39:26 -0700567 put_online_cpus();
568}
Vladimir Davydovb8529902014-04-07 15:39:28 -0700569
Vladimir Davydov2a4db7e2015-02-12 14:59:32 -0800570void memcg_deactivate_kmem_caches(struct mem_cgroup *memcg)
571{
572 int idx;
573 struct memcg_cache_array *arr;
Vladimir Davydovd6e0b7f2015-02-12 14:59:47 -0800574 struct kmem_cache *s, *c;
Vladimir Davydov2a4db7e2015-02-12 14:59:32 -0800575
576 idx = memcg_cache_id(memcg);
577
Vladimir Davydovd6e0b7f2015-02-12 14:59:47 -0800578 get_online_cpus();
579 get_online_mems();
580
Vladimir Davydov2a4db7e2015-02-12 14:59:32 -0800581 mutex_lock(&slab_mutex);
582 list_for_each_entry(s, &slab_caches, list) {
583 if (!is_root_cache(s))
584 continue;
585
586 arr = rcu_dereference_protected(s->memcg_params.memcg_caches,
587 lockdep_is_held(&slab_mutex));
Vladimir Davydovd6e0b7f2015-02-12 14:59:47 -0800588 c = arr->entries[idx];
589 if (!c)
590 continue;
591
592 __kmem_cache_shrink(c, true);
Vladimir Davydov2a4db7e2015-02-12 14:59:32 -0800593 arr->entries[idx] = NULL;
594 }
595 mutex_unlock(&slab_mutex);
Vladimir Davydovd6e0b7f2015-02-12 14:59:47 -0800596
597 put_online_mems();
598 put_online_cpus();
Vladimir Davydov2a4db7e2015-02-12 14:59:32 -0800599}
600
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800601void memcg_destroy_kmem_caches(struct mem_cgroup *memcg)
Vladimir Davydovb8529902014-04-07 15:39:28 -0700602{
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800603 LIST_HEAD(release);
604 bool need_rcu_barrier = false;
605 struct kmem_cache *s, *s2;
Vladimir Davydovb8529902014-04-07 15:39:28 -0700606
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800607 get_online_cpus();
608 get_online_mems();
Vladimir Davydovb8529902014-04-07 15:39:28 -0700609
Vladimir Davydovb8529902014-04-07 15:39:28 -0700610 mutex_lock(&slab_mutex);
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800611 list_for_each_entry_safe(s, s2, &slab_caches, list) {
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800612 if (is_root_cache(s) || s->memcg_params.memcg != memcg)
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800613 continue;
614 /*
615 * The cgroup is about to be freed and therefore has no charges
616 * left. Hence, all its caches must be empty by now.
617 */
618 BUG_ON(do_kmem_cache_shutdown(s, &release, &need_rcu_barrier));
619 }
620 mutex_unlock(&slab_mutex);
Vladimir Davydovb8529902014-04-07 15:39:28 -0700621
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800622 put_online_mems();
623 put_online_cpus();
624
625 do_kmem_cache_release(&release, need_rcu_barrier);
Vladimir Davydovb8529902014-04-07 15:39:28 -0700626}
Vladimir Davydov794b1242014-04-07 15:39:26 -0700627#endif /* CONFIG_MEMCG_KMEM */
628
Christoph Lameter41a21282014-05-06 12:50:08 -0700629void slab_kmem_cache_release(struct kmem_cache *s)
630{
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800631 destroy_memcg_params(s);
Andrzej Hajda3dec16e2015-02-13 14:36:38 -0800632 kfree_const(s->name);
Christoph Lameter41a21282014-05-06 12:50:08 -0700633 kmem_cache_free(kmem_cache, s);
634}
635
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000636void kmem_cache_destroy(struct kmem_cache *s)
637{
Vladimir Davydov426589f2015-02-12 14:59:23 -0800638 struct kmem_cache *c, *c2;
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800639 LIST_HEAD(release);
640 bool need_rcu_barrier = false;
641 bool busy = false;
642
Sergey Senozhatsky3942d292015-09-08 15:00:50 -0700643 if (unlikely(!s))
644 return;
645
Vladimir Davydov426589f2015-02-12 14:59:23 -0800646 BUG_ON(!is_root_cache(s));
647
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000648 get_online_cpus();
Vladimir Davydov03afc0e2014-06-04 16:07:20 -0700649 get_online_mems();
650
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000651 mutex_lock(&slab_mutex);
Vladimir Davydovb8529902014-04-07 15:39:28 -0700652
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000653 s->refcount--;
Vladimir Davydovb8529902014-04-07 15:39:28 -0700654 if (s->refcount)
655 goto out_unlock;
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000656
Vladimir Davydov426589f2015-02-12 14:59:23 -0800657 for_each_memcg_cache_safe(c, c2, s) {
658 if (do_kmem_cache_shutdown(c, &release, &need_rcu_barrier))
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800659 busy = true;
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000660 }
Vladimir Davydovb8529902014-04-07 15:39:28 -0700661
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800662 if (!busy)
663 do_kmem_cache_shutdown(s, &release, &need_rcu_barrier);
Vladimir Davydovb8529902014-04-07 15:39:28 -0700664
665out_unlock:
666 mutex_unlock(&slab_mutex);
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800667
Vladimir Davydov03afc0e2014-06-04 16:07:20 -0700668 put_online_mems();
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000669 put_online_cpus();
Vladimir Davydovd5b3cf72015-02-10 14:11:47 -0800670
671 do_kmem_cache_release(&release, need_rcu_barrier);
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000672}
673EXPORT_SYMBOL(kmem_cache_destroy);
674
Vladimir Davydov03afc0e2014-06-04 16:07:20 -0700675/**
676 * kmem_cache_shrink - Shrink a cache.
677 * @cachep: The cache to shrink.
678 *
679 * Releases as many slabs as possible for a cache.
680 * To help debugging, a zero exit status indicates all slabs were released.
681 */
682int kmem_cache_shrink(struct kmem_cache *cachep)
683{
684 int ret;
685
686 get_online_cpus();
687 get_online_mems();
Vladimir Davydovd6e0b7f2015-02-12 14:59:47 -0800688 ret = __kmem_cache_shrink(cachep, false);
Vladimir Davydov03afc0e2014-06-04 16:07:20 -0700689 put_online_mems();
690 put_online_cpus();
691 return ret;
692}
693EXPORT_SYMBOL(kmem_cache_shrink);
694
Christoph Lameter97d06602012-07-06 15:25:11 -0500695int slab_is_available(void)
696{
697 return slab_state >= UP;
698}
Glauber Costab7454ad2012-10-19 18:20:25 +0400699
Christoph Lameter45530c42012-11-28 16:23:07 +0000700#ifndef CONFIG_SLOB
701/* Create a cache during boot when no slab services are available yet */
702void __init create_boot_cache(struct kmem_cache *s, const char *name, size_t size,
703 unsigned long flags)
704{
705 int err;
706
707 s->name = name;
708 s->size = s->object_size = size;
Christoph Lameter45906852012-11-28 16:23:16 +0000709 s->align = calculate_alignment(flags, ARCH_KMALLOC_MINALIGN, size);
Vladimir Davydovf7ce3192015-02-12 14:59:20 -0800710
711 slab_init_memcg_params(s);
712
Christoph Lameter45530c42012-11-28 16:23:07 +0000713 err = __kmem_cache_create(s, flags);
714
715 if (err)
Christoph Lameter31ba7342013-01-10 19:00:53 +0000716 panic("Creation of kmalloc slab %s size=%zu failed. Reason %d\n",
Christoph Lameter45530c42012-11-28 16:23:07 +0000717 name, size, err);
718
719 s->refcount = -1; /* Exempt from merging for now */
720}
721
722struct kmem_cache *__init create_kmalloc_cache(const char *name, size_t size,
723 unsigned long flags)
724{
725 struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT);
726
727 if (!s)
728 panic("Out of memory when creating slab %s\n", name);
729
730 create_boot_cache(s, name, size, flags);
731 list_add(&s->list, &slab_caches);
732 s->refcount = 1;
733 return s;
734}
735
Christoph Lameter9425c582013-01-10 19:12:17 +0000736struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
737EXPORT_SYMBOL(kmalloc_caches);
738
739#ifdef CONFIG_ZONE_DMA
740struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
741EXPORT_SYMBOL(kmalloc_dma_caches);
742#endif
743
Christoph Lameterf97d5f62013-01-10 19:12:17 +0000744/*
Christoph Lameter2c59dd62013-01-10 19:14:19 +0000745 * Conversion table for small slabs sizes / 8 to the index in the
746 * kmalloc array. This is necessary for slabs < 192 since we have non power
747 * of two cache sizes there. The size of larger slabs can be determined using
748 * fls.
749 */
750static s8 size_index[24] = {
751 3, /* 8 */
752 4, /* 16 */
753 5, /* 24 */
754 5, /* 32 */
755 6, /* 40 */
756 6, /* 48 */
757 6, /* 56 */
758 6, /* 64 */
759 1, /* 72 */
760 1, /* 80 */
761 1, /* 88 */
762 1, /* 96 */
763 7, /* 104 */
764 7, /* 112 */
765 7, /* 120 */
766 7, /* 128 */
767 2, /* 136 */
768 2, /* 144 */
769 2, /* 152 */
770 2, /* 160 */
771 2, /* 168 */
772 2, /* 176 */
773 2, /* 184 */
774 2 /* 192 */
775};
776
777static inline int size_index_elem(size_t bytes)
778{
779 return (bytes - 1) / 8;
780}
781
782/*
783 * Find the kmem_cache structure that serves a given size of
784 * allocation
785 */
786struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags)
787{
788 int index;
789
Joonsoo Kim9de1bc82013-08-02 11:02:42 +0900790 if (unlikely(size > KMALLOC_MAX_SIZE)) {
Sasha Levin907985f2013-06-10 15:18:00 -0400791 WARN_ON_ONCE(!(flags & __GFP_NOWARN));
Christoph Lameter6286ae92013-05-03 15:43:18 +0000792 return NULL;
Sasha Levin907985f2013-06-10 15:18:00 -0400793 }
Christoph Lameter6286ae92013-05-03 15:43:18 +0000794
Christoph Lameter2c59dd62013-01-10 19:14:19 +0000795 if (size <= 192) {
796 if (!size)
797 return ZERO_SIZE_PTR;
798
799 index = size_index[size_index_elem(size)];
800 } else
801 index = fls(size - 1);
802
803#ifdef CONFIG_ZONE_DMA
Joonsoo Kimb1e05412013-02-04 23:46:46 +0900804 if (unlikely((flags & GFP_DMA)))
Christoph Lameter2c59dd62013-01-10 19:14:19 +0000805 return kmalloc_dma_caches[index];
806
807#endif
808 return kmalloc_caches[index];
809}
810
811/*
Gavin Guo4066c332015-06-24 16:55:54 -0700812 * kmalloc_info[] is to make slub_debug=,kmalloc-xx option work at boot time.
813 * kmalloc_index() supports up to 2^26=64MB, so the final entry of the table is
814 * kmalloc-67108864.
815 */
816static struct {
817 const char *name;
818 unsigned long size;
819} const kmalloc_info[] __initconst = {
820 {NULL, 0}, {"kmalloc-96", 96},
821 {"kmalloc-192", 192}, {"kmalloc-8", 8},
822 {"kmalloc-16", 16}, {"kmalloc-32", 32},
823 {"kmalloc-64", 64}, {"kmalloc-128", 128},
824 {"kmalloc-256", 256}, {"kmalloc-512", 512},
825 {"kmalloc-1024", 1024}, {"kmalloc-2048", 2048},
826 {"kmalloc-4096", 4096}, {"kmalloc-8192", 8192},
827 {"kmalloc-16384", 16384}, {"kmalloc-32768", 32768},
828 {"kmalloc-65536", 65536}, {"kmalloc-131072", 131072},
829 {"kmalloc-262144", 262144}, {"kmalloc-524288", 524288},
830 {"kmalloc-1048576", 1048576}, {"kmalloc-2097152", 2097152},
831 {"kmalloc-4194304", 4194304}, {"kmalloc-8388608", 8388608},
832 {"kmalloc-16777216", 16777216}, {"kmalloc-33554432", 33554432},
833 {"kmalloc-67108864", 67108864}
834};
835
836/*
Daniel Sanders34cc6992015-06-24 16:55:57 -0700837 * Patch up the size_index table if we have strange large alignment
838 * requirements for the kmalloc array. This is only the case for
839 * MIPS it seems. The standard arches will not generate any code here.
840 *
841 * Largest permitted alignment is 256 bytes due to the way we
842 * handle the index determination for the smaller caches.
843 *
844 * Make sure that nothing crazy happens if someone starts tinkering
845 * around with ARCH_KMALLOC_MINALIGN
Christoph Lameterf97d5f62013-01-10 19:12:17 +0000846 */
Daniel Sanders34cc6992015-06-24 16:55:57 -0700847void __init setup_kmalloc_cache_index_table(void)
Christoph Lameterf97d5f62013-01-10 19:12:17 +0000848{
849 int i;
850
Christoph Lameter2c59dd62013-01-10 19:14:19 +0000851 BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 ||
852 (KMALLOC_MIN_SIZE & (KMALLOC_MIN_SIZE - 1)));
853
854 for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) {
855 int elem = size_index_elem(i);
856
857 if (elem >= ARRAY_SIZE(size_index))
858 break;
859 size_index[elem] = KMALLOC_SHIFT_LOW;
860 }
861
862 if (KMALLOC_MIN_SIZE >= 64) {
863 /*
864 * The 96 byte size cache is not used if the alignment
865 * is 64 byte.
866 */
867 for (i = 64 + 8; i <= 96; i += 8)
868 size_index[size_index_elem(i)] = 7;
869
870 }
871
872 if (KMALLOC_MIN_SIZE >= 128) {
873 /*
874 * The 192 byte sized cache is not used if the alignment
875 * is 128 byte. Redirect kmalloc to use the 256 byte cache
876 * instead.
877 */
878 for (i = 128 + 8; i <= 192; i += 8)
879 size_index[size_index_elem(i)] = 8;
880 }
Daniel Sanders34cc6992015-06-24 16:55:57 -0700881}
882
Christoph Lameterae6f2462015-06-30 09:01:11 -0500883static void __init new_kmalloc_cache(int idx, unsigned long flags)
Christoph Lametera9730fc2015-06-29 09:28:08 -0500884{
885 kmalloc_caches[idx] = create_kmalloc_cache(kmalloc_info[idx].name,
886 kmalloc_info[idx].size, flags);
887}
888
Daniel Sanders34cc6992015-06-24 16:55:57 -0700889/*
890 * Create the kmalloc array. Some of the regular kmalloc arrays
891 * may already have been created because they were needed to
892 * enable allocations for slab creation.
893 */
894void __init create_kmalloc_caches(unsigned long flags)
895{
896 int i;
897
Christoph Lametera9730fc2015-06-29 09:28:08 -0500898 for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) {
899 if (!kmalloc_caches[i])
900 new_kmalloc_cache(i, flags);
Chris Mason956e46e2013-05-08 15:56:28 -0400901
902 /*
Christoph Lametera9730fc2015-06-29 09:28:08 -0500903 * Caches that are not of the two-to-the-power-of size.
904 * These have to be created immediately after the
905 * earlier power of two caches
Chris Mason956e46e2013-05-08 15:56:28 -0400906 */
Christoph Lametera9730fc2015-06-29 09:28:08 -0500907 if (KMALLOC_MIN_SIZE <= 32 && !kmalloc_caches[1] && i == 6)
908 new_kmalloc_cache(1, flags);
909 if (KMALLOC_MIN_SIZE <= 64 && !kmalloc_caches[2] && i == 7)
910 new_kmalloc_cache(2, flags);
Christoph Lameter8a965b32013-05-03 18:04:18 +0000911 }
912
Christoph Lameterf97d5f62013-01-10 19:12:17 +0000913 /* Kmalloc array is now usable */
914 slab_state = UP;
915
Christoph Lameterf97d5f62013-01-10 19:12:17 +0000916#ifdef CONFIG_ZONE_DMA
917 for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) {
918 struct kmem_cache *s = kmalloc_caches[i];
919
920 if (s) {
921 int size = kmalloc_size(i);
922 char *n = kasprintf(GFP_NOWAIT,
923 "dma-kmalloc-%d", size);
924
925 BUG_ON(!n);
926 kmalloc_dma_caches[i] = create_kmalloc_cache(n,
927 size, SLAB_CACHE_DMA | flags);
928 }
929 }
930#endif
931}
Christoph Lameter45530c42012-11-28 16:23:07 +0000932#endif /* !CONFIG_SLOB */
933
Vladimir Davydovcea371f2014-06-04 16:07:04 -0700934/*
935 * To avoid unnecessary overhead, we pass through large allocation requests
936 * directly to the page allocator. We use __GFP_COMP, because we will need to
937 * know the allocation order to free the pages properly in kfree.
938 */
Vladimir Davydov52383432014-06-04 16:06:39 -0700939void *kmalloc_order(size_t size, gfp_t flags, unsigned int order)
940{
941 void *ret;
942 struct page *page;
943
944 flags |= __GFP_COMP;
945 page = alloc_kmem_pages(flags, order);
946 ret = page ? page_address(page) : NULL;
947 kmemleak_alloc(ret, size, 1, flags);
Andrey Ryabinin0316bec2015-02-13 14:39:42 -0800948 kasan_kmalloc_large(ret, size);
Vladimir Davydov52383432014-06-04 16:06:39 -0700949 return ret;
950}
951EXPORT_SYMBOL(kmalloc_order);
952
Christoph Lameterf1b6eb62013-09-04 16:35:34 +0000953#ifdef CONFIG_TRACING
954void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
955{
956 void *ret = kmalloc_order(size, flags, order);
957 trace_kmalloc(_RET_IP_, ret, size, PAGE_SIZE << order, flags);
958 return ret;
959}
960EXPORT_SYMBOL(kmalloc_order_trace);
961#endif
Christoph Lameter45530c42012-11-28 16:23:07 +0000962
Glauber Costab7454ad2012-10-19 18:20:25 +0400963#ifdef CONFIG_SLABINFO
Wanpeng Lie9b4db22013-07-04 08:33:24 +0800964
965#ifdef CONFIG_SLAB
966#define SLABINFO_RIGHTS (S_IWUSR | S_IRUSR)
967#else
968#define SLABINFO_RIGHTS S_IRUSR
969#endif
970
Vladimir Davydovb0475012014-12-10 15:44:19 -0800971static void print_slabinfo_header(struct seq_file *m)
Glauber Costabcee6e22012-10-19 18:20:26 +0400972{
973 /*
974 * Output format version, so at least we can change it
975 * without _too_ many complaints.
976 */
977#ifdef CONFIG_DEBUG_SLAB
978 seq_puts(m, "slabinfo - version: 2.1 (statistics)\n");
979#else
980 seq_puts(m, "slabinfo - version: 2.1\n");
981#endif
982 seq_puts(m, "# name <active_objs> <num_objs> <objsize> "
983 "<objperslab> <pagesperslab>");
984 seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
985 seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
986#ifdef CONFIG_DEBUG_SLAB
987 seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> "
988 "<error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>");
989 seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>");
990#endif
991 seq_putc(m, '\n');
992}
993
Vladimir Davydov1df3b262014-12-10 15:42:16 -0800994void *slab_start(struct seq_file *m, loff_t *pos)
Glauber Costab7454ad2012-10-19 18:20:25 +0400995{
Glauber Costab7454ad2012-10-19 18:20:25 +0400996 mutex_lock(&slab_mutex);
Glauber Costab7454ad2012-10-19 18:20:25 +0400997 return seq_list_start(&slab_caches, *pos);
998}
999
Wanpeng Li276a2432013-07-08 08:08:28 +08001000void *slab_next(struct seq_file *m, void *p, loff_t *pos)
Glauber Costab7454ad2012-10-19 18:20:25 +04001001{
1002 return seq_list_next(p, &slab_caches, pos);
1003}
1004
Wanpeng Li276a2432013-07-08 08:08:28 +08001005void slab_stop(struct seq_file *m, void *p)
Glauber Costab7454ad2012-10-19 18:20:25 +04001006{
1007 mutex_unlock(&slab_mutex);
1008}
1009
Glauber Costa749c5412012-12-18 14:23:01 -08001010static void
1011memcg_accumulate_slabinfo(struct kmem_cache *s, struct slabinfo *info)
Glauber Costab7454ad2012-10-19 18:20:25 +04001012{
Glauber Costa749c5412012-12-18 14:23:01 -08001013 struct kmem_cache *c;
1014 struct slabinfo sinfo;
Glauber Costa749c5412012-12-18 14:23:01 -08001015
1016 if (!is_root_cache(s))
1017 return;
1018
Vladimir Davydov426589f2015-02-12 14:59:23 -08001019 for_each_memcg_cache(c, s) {
Glauber Costa749c5412012-12-18 14:23:01 -08001020 memset(&sinfo, 0, sizeof(sinfo));
1021 get_slabinfo(c, &sinfo);
1022
1023 info->active_slabs += sinfo.active_slabs;
1024 info->num_slabs += sinfo.num_slabs;
1025 info->shared_avail += sinfo.shared_avail;
1026 info->active_objs += sinfo.active_objs;
1027 info->num_objs += sinfo.num_objs;
1028 }
1029}
1030
Vladimir Davydovb0475012014-12-10 15:44:19 -08001031static void cache_show(struct kmem_cache *s, struct seq_file *m)
Glauber Costa749c5412012-12-18 14:23:01 -08001032{
Glauber Costa0d7561c2012-10-19 18:20:27 +04001033 struct slabinfo sinfo;
1034
1035 memset(&sinfo, 0, sizeof(sinfo));
1036 get_slabinfo(s, &sinfo);
1037
Glauber Costa749c5412012-12-18 14:23:01 -08001038 memcg_accumulate_slabinfo(s, &sinfo);
1039
Glauber Costa0d7561c2012-10-19 18:20:27 +04001040 seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d",
Glauber Costa749c5412012-12-18 14:23:01 -08001041 cache_name(s), sinfo.active_objs, sinfo.num_objs, s->size,
Glauber Costa0d7561c2012-10-19 18:20:27 +04001042 sinfo.objects_per_slab, (1 << sinfo.cache_order));
1043
1044 seq_printf(m, " : tunables %4u %4u %4u",
1045 sinfo.limit, sinfo.batchcount, sinfo.shared);
1046 seq_printf(m, " : slabdata %6lu %6lu %6lu",
1047 sinfo.active_slabs, sinfo.num_slabs, sinfo.shared_avail);
1048 slabinfo_show_stats(m, s);
1049 seq_putc(m, '\n');
Glauber Costab7454ad2012-10-19 18:20:25 +04001050}
1051
Vladimir Davydov1df3b262014-12-10 15:42:16 -08001052static int slab_show(struct seq_file *m, void *p)
Glauber Costa749c5412012-12-18 14:23:01 -08001053{
1054 struct kmem_cache *s = list_entry(p, struct kmem_cache, list);
1055
Vladimir Davydov1df3b262014-12-10 15:42:16 -08001056 if (p == slab_caches.next)
1057 print_slabinfo_header(m);
Vladimir Davydovb0475012014-12-10 15:44:19 -08001058 if (is_root_cache(s))
1059 cache_show(s, m);
1060 return 0;
Glauber Costa749c5412012-12-18 14:23:01 -08001061}
1062
Vladimir Davydovb0475012014-12-10 15:44:19 -08001063#ifdef CONFIG_MEMCG_KMEM
1064int memcg_slab_show(struct seq_file *m, void *p)
1065{
1066 struct kmem_cache *s = list_entry(p, struct kmem_cache, list);
1067 struct mem_cgroup *memcg = mem_cgroup_from_css(seq_css(m));
1068
1069 if (p == slab_caches.next)
1070 print_slabinfo_header(m);
Vladimir Davydovf7ce3192015-02-12 14:59:20 -08001071 if (!is_root_cache(s) && s->memcg_params.memcg == memcg)
Vladimir Davydovb0475012014-12-10 15:44:19 -08001072 cache_show(s, m);
1073 return 0;
1074}
1075#endif
1076
Glauber Costab7454ad2012-10-19 18:20:25 +04001077/*
1078 * slabinfo_op - iterator that generates /proc/slabinfo
1079 *
1080 * Output layout:
1081 * cache-name
1082 * num-active-objs
1083 * total-objs
1084 * object size
1085 * num-active-slabs
1086 * total-slabs
1087 * num-pages-per-slab
1088 * + further values on SMP and with statistics enabled
1089 */
1090static const struct seq_operations slabinfo_op = {
Vladimir Davydov1df3b262014-12-10 15:42:16 -08001091 .start = slab_start,
Wanpeng Li276a2432013-07-08 08:08:28 +08001092 .next = slab_next,
1093 .stop = slab_stop,
Vladimir Davydov1df3b262014-12-10 15:42:16 -08001094 .show = slab_show,
Glauber Costab7454ad2012-10-19 18:20:25 +04001095};
1096
1097static int slabinfo_open(struct inode *inode, struct file *file)
1098{
1099 return seq_open(file, &slabinfo_op);
1100}
1101
1102static const struct file_operations proc_slabinfo_operations = {
1103 .open = slabinfo_open,
1104 .read = seq_read,
1105 .write = slabinfo_write,
1106 .llseek = seq_lseek,
1107 .release = seq_release,
1108};
1109
1110static int __init slab_proc_init(void)
1111{
Wanpeng Lie9b4db22013-07-04 08:33:24 +08001112 proc_create("slabinfo", SLABINFO_RIGHTS, NULL,
1113 &proc_slabinfo_operations);
Glauber Costab7454ad2012-10-19 18:20:25 +04001114 return 0;
1115}
1116module_init(slab_proc_init);
1117#endif /* CONFIG_SLABINFO */
Andrey Ryabinin928cec92014-08-06 16:04:44 -07001118
1119static __always_inline void *__do_krealloc(const void *p, size_t new_size,
1120 gfp_t flags)
1121{
1122 void *ret;
1123 size_t ks = 0;
1124
1125 if (p)
1126 ks = ksize(p);
1127
Andrey Ryabinin0316bec2015-02-13 14:39:42 -08001128 if (ks >= new_size) {
1129 kasan_krealloc((void *)p, new_size);
Andrey Ryabinin928cec92014-08-06 16:04:44 -07001130 return (void *)p;
Andrey Ryabinin0316bec2015-02-13 14:39:42 -08001131 }
Andrey Ryabinin928cec92014-08-06 16:04:44 -07001132
1133 ret = kmalloc_track_caller(new_size, flags);
1134 if (ret && p)
1135 memcpy(ret, p, ks);
1136
1137 return ret;
1138}
1139
1140/**
1141 * __krealloc - like krealloc() but don't free @p.
1142 * @p: object to reallocate memory for.
1143 * @new_size: how many bytes of memory are required.
1144 * @flags: the type of memory to allocate.
1145 *
1146 * This function is like krealloc() except it never frees the originally
1147 * allocated buffer. Use this if you don't want to free the buffer immediately
1148 * like, for example, with RCU.
1149 */
1150void *__krealloc(const void *p, size_t new_size, gfp_t flags)
1151{
1152 if (unlikely(!new_size))
1153 return ZERO_SIZE_PTR;
1154
1155 return __do_krealloc(p, new_size, flags);
1156
1157}
1158EXPORT_SYMBOL(__krealloc);
1159
1160/**
1161 * krealloc - reallocate memory. The contents will remain unchanged.
1162 * @p: object to reallocate memory for.
1163 * @new_size: how many bytes of memory are required.
1164 * @flags: the type of memory to allocate.
1165 *
1166 * The contents of the object pointed to are preserved up to the
1167 * lesser of the new and old sizes. If @p is %NULL, krealloc()
1168 * behaves exactly like kmalloc(). If @new_size is 0 and @p is not a
1169 * %NULL pointer, the object pointed to is freed.
1170 */
1171void *krealloc(const void *p, size_t new_size, gfp_t flags)
1172{
1173 void *ret;
1174
1175 if (unlikely(!new_size)) {
1176 kfree(p);
1177 return ZERO_SIZE_PTR;
1178 }
1179
1180 ret = __do_krealloc(p, new_size, flags);
1181 if (ret && p != ret)
1182 kfree(p);
1183
1184 return ret;
1185}
1186EXPORT_SYMBOL(krealloc);
1187
1188/**
1189 * kzfree - like kfree but zero memory
1190 * @p: object to free memory of
1191 *
1192 * The memory of the object @p points to is zeroed before freed.
1193 * If @p is %NULL, kzfree() does nothing.
1194 *
1195 * Note: this function zeroes the whole allocated buffer which can be a good
1196 * deal bigger than the requested buffer size passed to kmalloc(). So be
1197 * careful when using this function in performance sensitive code.
1198 */
1199void kzfree(const void *p)
1200{
1201 size_t ks;
1202 void *mem = (void *)p;
1203
1204 if (unlikely(ZERO_OR_NULL_PTR(mem)))
1205 return;
1206 ks = ksize(mem);
1207 memset(mem, 0, ks);
1208 kfree(mem);
1209}
1210EXPORT_SYMBOL(kzfree);
1211
1212/* Tracepoints definitions. */
1213EXPORT_TRACEPOINT_SYMBOL(kmalloc);
1214EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);
1215EXPORT_TRACEPOINT_SYMBOL(kmalloc_node);
1216EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc_node);
1217EXPORT_TRACEPOINT_SYMBOL(kfree);
1218EXPORT_TRACEPOINT_SYMBOL(kmem_cache_free);