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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>
Christoph Lameterf1b6eb62013-09-04 16:35:34 +000022#include <trace/events/kmem.h>
Christoph Lameter039363f2012-07-06 15:25:10 -050023
Christoph Lameter97d06602012-07-06 15:25:11 -050024#include "slab.h"
25
26enum slab_state slab_state;
Christoph Lameter18004c52012-07-06 15:25:12 -050027LIST_HEAD(slab_caches);
28DEFINE_MUTEX(slab_mutex);
Christoph Lameter9b030cb2012-09-05 00:20:33 +000029struct kmem_cache *kmem_cache;
Christoph Lameter97d06602012-07-06 15:25:11 -050030
Shuah Khan77be4b12012-08-16 00:09:46 -070031#ifdef CONFIG_DEBUG_VM
Glauber Costa2633d7a2012-12-18 14:22:34 -080032static int kmem_cache_sanity_check(struct mem_cgroup *memcg, const char *name,
33 size_t size)
Shuah Khan77be4b12012-08-16 00:09:46 -070034{
35 struct kmem_cache *s = NULL;
36
37 if (!name || in_interrupt() || size < sizeof(void *) ||
38 size > KMALLOC_MAX_SIZE) {
39 pr_err("kmem_cache_create(%s) integrity check failed\n", name);
40 return -EINVAL;
41 }
42
43 list_for_each_entry(s, &slab_caches, list) {
44 char tmp;
45 int res;
46
47 /*
48 * This happens when the module gets unloaded and doesn't
49 * destroy its slab cache and no-one else reuses the vmalloc
50 * area of the module. Print a warning.
51 */
52 res = probe_kernel_address(s->name, tmp);
53 if (res) {
54 pr_err("Slab cache with size %d has lost its name\n",
55 s->object_size);
56 continue;
57 }
58
Christoph Lameter3e374912013-09-21 21:56:34 +000059#if !defined(CONFIG_SLUB) || !defined(CONFIG_SLUB_DEBUG_ON)
Glauber Costa2633d7a2012-12-18 14:22:34 -080060 /*
61 * For simplicity, we won't check this in the list of memcg
62 * caches. We have control over memcg naming, and if there
63 * aren't duplicates in the global list, there won't be any
64 * duplicates in the memcg lists as well.
65 */
66 if (!memcg && !strcmp(s->name, name)) {
Shuah Khan77be4b12012-08-16 00:09:46 -070067 pr_err("%s (%s): Cache name already exists.\n",
68 __func__, name);
69 dump_stack();
70 s = NULL;
71 return -EINVAL;
72 }
Christoph Lameter3e374912013-09-21 21:56:34 +000073#endif
Shuah Khan77be4b12012-08-16 00:09:46 -070074 }
75
76 WARN_ON(strchr(name, ' ')); /* It confuses parsers */
77 return 0;
78}
79#else
Glauber Costa2633d7a2012-12-18 14:22:34 -080080static inline int kmem_cache_sanity_check(struct mem_cgroup *memcg,
81 const char *name, size_t size)
Shuah Khan77be4b12012-08-16 00:09:46 -070082{
83 return 0;
84}
85#endif
86
Glauber Costa55007d82012-12-18 14:22:38 -080087#ifdef CONFIG_MEMCG_KMEM
88int memcg_update_all_caches(int num_memcgs)
89{
90 struct kmem_cache *s;
91 int ret = 0;
92 mutex_lock(&slab_mutex);
93
94 list_for_each_entry(s, &slab_caches, list) {
95 if (!is_root_cache(s))
96 continue;
97
98 ret = memcg_update_cache_size(s, num_memcgs);
99 /*
100 * See comment in memcontrol.c, memcg_update_cache_size:
101 * Instead of freeing the memory, we'll just leave the caches
102 * up to this point in an updated state.
103 */
104 if (ret)
105 goto out;
106 }
107
108 memcg_update_array_size(num_memcgs);
109out:
110 mutex_unlock(&slab_mutex);
111 return ret;
112}
113#endif
114
Christoph Lameter039363f2012-07-06 15:25:10 -0500115/*
Christoph Lameter45906852012-11-28 16:23:16 +0000116 * Figure out what the alignment of the objects will be given a set of
117 * flags, a user specified alignment and the size of the objects.
118 */
119unsigned long calculate_alignment(unsigned long flags,
120 unsigned long align, unsigned long size)
121{
122 /*
123 * If the user wants hardware cache aligned objects then follow that
124 * suggestion if the object is sufficiently large.
125 *
126 * The hardware cache alignment cannot override the specified
127 * alignment though. If that is greater then use it.
128 */
129 if (flags & SLAB_HWCACHE_ALIGN) {
130 unsigned long ralign = cache_line_size();
131 while (size <= ralign / 2)
132 ralign /= 2;
133 align = max(align, ralign);
134 }
135
136 if (align < ARCH_SLAB_MINALIGN)
137 align = ARCH_SLAB_MINALIGN;
138
139 return ALIGN(align, sizeof(void *));
140}
141
142
143/*
Christoph Lameter039363f2012-07-06 15:25:10 -0500144 * kmem_cache_create - Create a cache.
145 * @name: A string which is used in /proc/slabinfo to identify this cache.
146 * @size: The size of objects to be created in this cache.
147 * @align: The required alignment for the objects.
148 * @flags: SLAB flags
149 * @ctor: A constructor for the objects.
150 *
151 * Returns a ptr to the cache on success, NULL on failure.
152 * Cannot be called within a interrupt, but can be interrupted.
153 * The @ctor is run when new pages are allocated by the cache.
154 *
155 * The flags are
156 *
157 * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5)
158 * to catch references to uninitialised memory.
159 *
160 * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check
161 * for buffer overruns.
162 *
163 * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware
164 * cacheline. This can be beneficial if you're counting cycles as closely
165 * as davem.
166 */
167
Glauber Costa2633d7a2012-12-18 14:22:34 -0800168struct kmem_cache *
169kmem_cache_create_memcg(struct mem_cgroup *memcg, const char *name, size_t size,
Glauber Costa943a4512012-12-18 14:23:03 -0800170 size_t align, unsigned long flags, void (*ctor)(void *),
171 struct kmem_cache *parent_cache)
Christoph Lameter039363f2012-07-06 15:25:10 -0500172{
173 struct kmem_cache *s = NULL;
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800174 int err;
Christoph Lameter039363f2012-07-06 15:25:10 -0500175
Pekka Enbergb9205362012-08-16 10:12:18 +0300176 get_online_cpus();
177 mutex_lock(&slab_mutex);
Christoph Lameter686d5502012-09-05 00:20:33 +0000178
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800179 err = kmem_cache_sanity_check(memcg, name, size);
180 if (err)
181 goto out_unlock;
Christoph Lameter686d5502012-09-05 00:20:33 +0000182
Vladimir Davydov2edefe12014-01-23 15:53:02 -0800183 if (memcg) {
184 /*
185 * Since per-memcg caches are created asynchronously on first
186 * allocation (see memcg_kmem_get_cache()), several threads can
187 * try to create the same cache, but only one of them may
188 * succeed. Therefore if we get here and see the cache has
189 * already been created, we silently return NULL.
190 */
191 if (cache_from_memcg_idx(parent_cache, memcg_cache_id(memcg)))
192 goto out_unlock;
193 }
194
Glauber Costad8843922012-10-17 15:36:51 +0400195 /*
196 * Some allocators will constraint the set of valid flags to a subset
197 * of all flags. We expect them to define CACHE_CREATE_MASK in this
198 * case, and we'll just provide them with a sanitized version of the
199 * passed flags.
200 */
201 flags &= CACHE_CREATE_MASK;
Christoph Lameter686d5502012-09-05 00:20:33 +0000202
Glauber Costa2633d7a2012-12-18 14:22:34 -0800203 s = __kmem_cache_alias(memcg, name, size, align, flags, ctor);
Christoph Lametercbb79692012-09-05 00:18:32 +0000204 if (s)
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800205 goto out_unlock;
Christoph Lametercbb79692012-09-05 00:18:32 +0000206
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800207 err = -ENOMEM;
Christoph Lameter278b1bb2012-09-05 00:20:34 +0000208 s = kmem_cache_zalloc(kmem_cache, GFP_KERNEL);
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800209 if (!s)
210 goto out_unlock;
Glauber Costa2633d7a2012-12-18 14:22:34 -0800211
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800212 s->object_size = s->size = size;
213 s->align = calculate_alignment(flags, align, size);
214 s->ctor = ctor;
Glauber Costa2633d7a2012-12-18 14:22:34 -0800215
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800216 s->name = kstrdup(name, GFP_KERNEL);
217 if (!s->name)
218 goto out_free_cache;
Christoph Lameter8a13a4c2012-09-04 23:18:33 +0000219
Vladimir Davydov363a0442014-01-23 15:52:56 -0800220 err = memcg_alloc_cache_params(memcg, s, parent_cache);
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800221 if (err)
222 goto out_free_cache;
Christoph Lameter7c9adf52012-09-04 23:38:33 +0000223
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800224 err = __kmem_cache_create(s, flags);
225 if (err)
226 goto out_free_cache;
227
228 s->refcount = 1;
229 list_add(&s->list, &slab_caches);
Vladimir Davydov1aa13252014-01-23 15:52:58 -0800230 memcg_register_cache(s);
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800231
232out_unlock:
Christoph Lameter20cea962012-07-06 15:25:13 -0500233 mutex_unlock(&slab_mutex);
234 put_online_cpus();
235
Dave Jonesba3253c2014-01-29 14:05:48 -0800236 if (err) {
237 /*
238 * There is no point in flooding logs with warnings or
239 * especially crashing the system if we fail to create a cache
240 * for a memcg. In this case we will be accounting the memcg
241 * allocation to the root cgroup until we succeed to create its
242 * own cache, but it isn't that critical.
243 */
244 if (!memcg)
245 return NULL;
246
Christoph Lameter686d5502012-09-05 00:20:33 +0000247 if (flags & SLAB_PANIC)
248 panic("kmem_cache_create: Failed to create slab '%s'. Error %d\n",
249 name, err);
250 else {
251 printk(KERN_WARNING "kmem_cache_create(%s) failed with error %d",
252 name, err);
253 dump_stack();
254 }
Christoph Lameter686d5502012-09-05 00:20:33 +0000255 return NULL;
256 }
Christoph Lameter039363f2012-07-06 15:25:10 -0500257 return s;
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800258
259out_free_cache:
Vladimir Davydov363a0442014-01-23 15:52:56 -0800260 memcg_free_cache_params(s);
Vladimir Davydov3965fc32014-01-23 15:52:55 -0800261 kfree(s->name);
262 kmem_cache_free(kmem_cache, s);
263 goto out_unlock;
Christoph Lameter039363f2012-07-06 15:25:10 -0500264}
Glauber Costa2633d7a2012-12-18 14:22:34 -0800265
266struct kmem_cache *
267kmem_cache_create(const char *name, size_t size, size_t align,
268 unsigned long flags, void (*ctor)(void *))
269{
Glauber Costa943a4512012-12-18 14:23:03 -0800270 return kmem_cache_create_memcg(NULL, name, size, align, flags, ctor, NULL);
Glauber Costa2633d7a2012-12-18 14:22:34 -0800271}
Christoph Lameter039363f2012-07-06 15:25:10 -0500272EXPORT_SYMBOL(kmem_cache_create);
Christoph Lameter97d06602012-07-06 15:25:11 -0500273
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000274void kmem_cache_destroy(struct kmem_cache *s)
275{
Glauber Costa7cf27982012-12-18 14:22:55 -0800276 /* Destroy all the children caches if we aren't a memcg cache */
277 kmem_cache_destroy_memcg_children(s);
278
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000279 get_online_cpus();
280 mutex_lock(&slab_mutex);
281 s->refcount--;
282 if (!s->refcount) {
283 list_del(&s->list);
284
285 if (!__kmem_cache_shutdown(s)) {
Vladimir Davydov2edefe12014-01-23 15:53:02 -0800286 memcg_unregister_cache(s);
Jiri Kosina210ed9d2012-10-08 09:26:01 +0200287 mutex_unlock(&slab_mutex);
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000288 if (s->flags & SLAB_DESTROY_BY_RCU)
289 rcu_barrier();
290
Vladimir Davydov1aa13252014-01-23 15:52:58 -0800291 memcg_free_cache_params(s);
Christoph Lameterdb265ec2012-09-04 23:18:33 +0000292 kfree(s->name);
Christoph Lameter8f4c7652012-09-05 00:18:32 +0000293 kmem_cache_free(kmem_cache, s);
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000294 } else {
295 list_add(&s->list, &slab_caches);
Jiri Kosina210ed9d2012-10-08 09:26:01 +0200296 mutex_unlock(&slab_mutex);
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000297 printk(KERN_ERR "kmem_cache_destroy %s: Slab cache still has objects\n",
298 s->name);
299 dump_stack();
300 }
Jiri Kosina210ed9d2012-10-08 09:26:01 +0200301 } else {
302 mutex_unlock(&slab_mutex);
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000303 }
Christoph Lameter945cf2b2012-09-04 23:18:33 +0000304 put_online_cpus();
305}
306EXPORT_SYMBOL(kmem_cache_destroy);
307
Christoph Lameter97d06602012-07-06 15:25:11 -0500308int slab_is_available(void)
309{
310 return slab_state >= UP;
311}
Glauber Costab7454ad2012-10-19 18:20:25 +0400312
Christoph Lameter45530c42012-11-28 16:23:07 +0000313#ifndef CONFIG_SLOB
314/* Create a cache during boot when no slab services are available yet */
315void __init create_boot_cache(struct kmem_cache *s, const char *name, size_t size,
316 unsigned long flags)
317{
318 int err;
319
320 s->name = name;
321 s->size = s->object_size = size;
Christoph Lameter45906852012-11-28 16:23:16 +0000322 s->align = calculate_alignment(flags, ARCH_KMALLOC_MINALIGN, size);
Christoph Lameter45530c42012-11-28 16:23:07 +0000323 err = __kmem_cache_create(s, flags);
324
325 if (err)
Christoph Lameter31ba7342013-01-10 19:00:53 +0000326 panic("Creation of kmalloc slab %s size=%zu failed. Reason %d\n",
Christoph Lameter45530c42012-11-28 16:23:07 +0000327 name, size, err);
328
329 s->refcount = -1; /* Exempt from merging for now */
330}
331
332struct kmem_cache *__init create_kmalloc_cache(const char *name, size_t size,
333 unsigned long flags)
334{
335 struct kmem_cache *s = kmem_cache_zalloc(kmem_cache, GFP_NOWAIT);
336
337 if (!s)
338 panic("Out of memory when creating slab %s\n", name);
339
340 create_boot_cache(s, name, size, flags);
341 list_add(&s->list, &slab_caches);
342 s->refcount = 1;
343 return s;
344}
345
Christoph Lameter9425c582013-01-10 19:12:17 +0000346struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
347EXPORT_SYMBOL(kmalloc_caches);
348
349#ifdef CONFIG_ZONE_DMA
350struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
351EXPORT_SYMBOL(kmalloc_dma_caches);
352#endif
353
Christoph Lameterf97d5f62013-01-10 19:12:17 +0000354/*
Christoph Lameter2c59dd62013-01-10 19:14:19 +0000355 * Conversion table for small slabs sizes / 8 to the index in the
356 * kmalloc array. This is necessary for slabs < 192 since we have non power
357 * of two cache sizes there. The size of larger slabs can be determined using
358 * fls.
359 */
360static s8 size_index[24] = {
361 3, /* 8 */
362 4, /* 16 */
363 5, /* 24 */
364 5, /* 32 */
365 6, /* 40 */
366 6, /* 48 */
367 6, /* 56 */
368 6, /* 64 */
369 1, /* 72 */
370 1, /* 80 */
371 1, /* 88 */
372 1, /* 96 */
373 7, /* 104 */
374 7, /* 112 */
375 7, /* 120 */
376 7, /* 128 */
377 2, /* 136 */
378 2, /* 144 */
379 2, /* 152 */
380 2, /* 160 */
381 2, /* 168 */
382 2, /* 176 */
383 2, /* 184 */
384 2 /* 192 */
385};
386
387static inline int size_index_elem(size_t bytes)
388{
389 return (bytes - 1) / 8;
390}
391
392/*
393 * Find the kmem_cache structure that serves a given size of
394 * allocation
395 */
396struct kmem_cache *kmalloc_slab(size_t size, gfp_t flags)
397{
398 int index;
399
Joonsoo Kim9de1bc82013-08-02 11:02:42 +0900400 if (unlikely(size > KMALLOC_MAX_SIZE)) {
Sasha Levin907985f2013-06-10 15:18:00 -0400401 WARN_ON_ONCE(!(flags & __GFP_NOWARN));
Christoph Lameter6286ae92013-05-03 15:43:18 +0000402 return NULL;
Sasha Levin907985f2013-06-10 15:18:00 -0400403 }
Christoph Lameter6286ae92013-05-03 15:43:18 +0000404
Christoph Lameter2c59dd62013-01-10 19:14:19 +0000405 if (size <= 192) {
406 if (!size)
407 return ZERO_SIZE_PTR;
408
409 index = size_index[size_index_elem(size)];
410 } else
411 index = fls(size - 1);
412
413#ifdef CONFIG_ZONE_DMA
Joonsoo Kimb1e05412013-02-04 23:46:46 +0900414 if (unlikely((flags & GFP_DMA)))
Christoph Lameter2c59dd62013-01-10 19:14:19 +0000415 return kmalloc_dma_caches[index];
416
417#endif
418 return kmalloc_caches[index];
419}
420
421/*
Christoph Lameterf97d5f62013-01-10 19:12:17 +0000422 * Create the kmalloc array. Some of the regular kmalloc arrays
423 * may already have been created because they were needed to
424 * enable allocations for slab creation.
425 */
426void __init create_kmalloc_caches(unsigned long flags)
427{
428 int i;
429
Christoph Lameter2c59dd62013-01-10 19:14:19 +0000430 /*
431 * Patch up the size_index table if we have strange large alignment
432 * requirements for the kmalloc array. This is only the case for
433 * MIPS it seems. The standard arches will not generate any code here.
434 *
435 * Largest permitted alignment is 256 bytes due to the way we
436 * handle the index determination for the smaller caches.
437 *
438 * Make sure that nothing crazy happens if someone starts tinkering
439 * around with ARCH_KMALLOC_MINALIGN
440 */
441 BUILD_BUG_ON(KMALLOC_MIN_SIZE > 256 ||
442 (KMALLOC_MIN_SIZE & (KMALLOC_MIN_SIZE - 1)));
443
444 for (i = 8; i < KMALLOC_MIN_SIZE; i += 8) {
445 int elem = size_index_elem(i);
446
447 if (elem >= ARRAY_SIZE(size_index))
448 break;
449 size_index[elem] = KMALLOC_SHIFT_LOW;
450 }
451
452 if (KMALLOC_MIN_SIZE >= 64) {
453 /*
454 * The 96 byte size cache is not used if the alignment
455 * is 64 byte.
456 */
457 for (i = 64 + 8; i <= 96; i += 8)
458 size_index[size_index_elem(i)] = 7;
459
460 }
461
462 if (KMALLOC_MIN_SIZE >= 128) {
463 /*
464 * The 192 byte sized cache is not used if the alignment
465 * is 128 byte. Redirect kmalloc to use the 256 byte cache
466 * instead.
467 */
468 for (i = 128 + 8; i <= 192; i += 8)
469 size_index[size_index_elem(i)] = 8;
470 }
Christoph Lameter8a965b32013-05-03 18:04:18 +0000471 for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++) {
472 if (!kmalloc_caches[i]) {
Christoph Lameterf97d5f62013-01-10 19:12:17 +0000473 kmalloc_caches[i] = create_kmalloc_cache(NULL,
474 1 << i, flags);
Christoph Lameter8a965b32013-05-03 18:04:18 +0000475 }
Chris Mason956e46e2013-05-08 15:56:28 -0400476
477 /*
478 * Caches that are not of the two-to-the-power-of size.
479 * These have to be created immediately after the
480 * earlier power of two caches
481 */
482 if (KMALLOC_MIN_SIZE <= 32 && !kmalloc_caches[1] && i == 6)
483 kmalloc_caches[1] = create_kmalloc_cache(NULL, 96, flags);
484
485 if (KMALLOC_MIN_SIZE <= 64 && !kmalloc_caches[2] && i == 7)
486 kmalloc_caches[2] = create_kmalloc_cache(NULL, 192, flags);
Christoph Lameter8a965b32013-05-03 18:04:18 +0000487 }
488
Christoph Lameterf97d5f62013-01-10 19:12:17 +0000489 /* Kmalloc array is now usable */
490 slab_state = UP;
491
492 for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) {
493 struct kmem_cache *s = kmalloc_caches[i];
494 char *n;
495
496 if (s) {
497 n = kasprintf(GFP_NOWAIT, "kmalloc-%d", kmalloc_size(i));
498
499 BUG_ON(!n);
500 s->name = n;
501 }
502 }
503
504#ifdef CONFIG_ZONE_DMA
505 for (i = 0; i <= KMALLOC_SHIFT_HIGH; i++) {
506 struct kmem_cache *s = kmalloc_caches[i];
507
508 if (s) {
509 int size = kmalloc_size(i);
510 char *n = kasprintf(GFP_NOWAIT,
511 "dma-kmalloc-%d", size);
512
513 BUG_ON(!n);
514 kmalloc_dma_caches[i] = create_kmalloc_cache(n,
515 size, SLAB_CACHE_DMA | flags);
516 }
517 }
518#endif
519}
Christoph Lameter45530c42012-11-28 16:23:07 +0000520#endif /* !CONFIG_SLOB */
521
Christoph Lameterf1b6eb62013-09-04 16:35:34 +0000522#ifdef CONFIG_TRACING
523void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
524{
525 void *ret = kmalloc_order(size, flags, order);
526 trace_kmalloc(_RET_IP_, ret, size, PAGE_SIZE << order, flags);
527 return ret;
528}
529EXPORT_SYMBOL(kmalloc_order_trace);
530#endif
Christoph Lameter45530c42012-11-28 16:23:07 +0000531
Glauber Costab7454ad2012-10-19 18:20:25 +0400532#ifdef CONFIG_SLABINFO
Wanpeng Lie9b4db22013-07-04 08:33:24 +0800533
534#ifdef CONFIG_SLAB
535#define SLABINFO_RIGHTS (S_IWUSR | S_IRUSR)
536#else
537#define SLABINFO_RIGHTS S_IRUSR
538#endif
539
Glauber Costa749c5412012-12-18 14:23:01 -0800540void print_slabinfo_header(struct seq_file *m)
Glauber Costabcee6e22012-10-19 18:20:26 +0400541{
542 /*
543 * Output format version, so at least we can change it
544 * without _too_ many complaints.
545 */
546#ifdef CONFIG_DEBUG_SLAB
547 seq_puts(m, "slabinfo - version: 2.1 (statistics)\n");
548#else
549 seq_puts(m, "slabinfo - version: 2.1\n");
550#endif
551 seq_puts(m, "# name <active_objs> <num_objs> <objsize> "
552 "<objperslab> <pagesperslab>");
553 seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
554 seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
555#ifdef CONFIG_DEBUG_SLAB
556 seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> "
557 "<error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>");
558 seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>");
559#endif
560 seq_putc(m, '\n');
561}
562
Glauber Costab7454ad2012-10-19 18:20:25 +0400563static void *s_start(struct seq_file *m, loff_t *pos)
564{
565 loff_t n = *pos;
566
567 mutex_lock(&slab_mutex);
568 if (!n)
569 print_slabinfo_header(m);
570
571 return seq_list_start(&slab_caches, *pos);
572}
573
Wanpeng Li276a2432013-07-08 08:08:28 +0800574void *slab_next(struct seq_file *m, void *p, loff_t *pos)
Glauber Costab7454ad2012-10-19 18:20:25 +0400575{
576 return seq_list_next(p, &slab_caches, pos);
577}
578
Wanpeng Li276a2432013-07-08 08:08:28 +0800579void slab_stop(struct seq_file *m, void *p)
Glauber Costab7454ad2012-10-19 18:20:25 +0400580{
581 mutex_unlock(&slab_mutex);
582}
583
Glauber Costa749c5412012-12-18 14:23:01 -0800584static void
585memcg_accumulate_slabinfo(struct kmem_cache *s, struct slabinfo *info)
Glauber Costab7454ad2012-10-19 18:20:25 +0400586{
Glauber Costa749c5412012-12-18 14:23:01 -0800587 struct kmem_cache *c;
588 struct slabinfo sinfo;
589 int i;
590
591 if (!is_root_cache(s))
592 return;
593
594 for_each_memcg_cache_index(i) {
Qiang Huang2ade4de2013-11-12 15:08:23 -0800595 c = cache_from_memcg_idx(s, i);
Glauber Costa749c5412012-12-18 14:23:01 -0800596 if (!c)
597 continue;
598
599 memset(&sinfo, 0, sizeof(sinfo));
600 get_slabinfo(c, &sinfo);
601
602 info->active_slabs += sinfo.active_slabs;
603 info->num_slabs += sinfo.num_slabs;
604 info->shared_avail += sinfo.shared_avail;
605 info->active_objs += sinfo.active_objs;
606 info->num_objs += sinfo.num_objs;
607 }
608}
609
610int cache_show(struct kmem_cache *s, struct seq_file *m)
611{
Glauber Costa0d7561c2012-10-19 18:20:27 +0400612 struct slabinfo sinfo;
613
614 memset(&sinfo, 0, sizeof(sinfo));
615 get_slabinfo(s, &sinfo);
616
Glauber Costa749c5412012-12-18 14:23:01 -0800617 memcg_accumulate_slabinfo(s, &sinfo);
618
Glauber Costa0d7561c2012-10-19 18:20:27 +0400619 seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d",
Glauber Costa749c5412012-12-18 14:23:01 -0800620 cache_name(s), sinfo.active_objs, sinfo.num_objs, s->size,
Glauber Costa0d7561c2012-10-19 18:20:27 +0400621 sinfo.objects_per_slab, (1 << sinfo.cache_order));
622
623 seq_printf(m, " : tunables %4u %4u %4u",
624 sinfo.limit, sinfo.batchcount, sinfo.shared);
625 seq_printf(m, " : slabdata %6lu %6lu %6lu",
626 sinfo.active_slabs, sinfo.num_slabs, sinfo.shared_avail);
627 slabinfo_show_stats(m, s);
628 seq_putc(m, '\n');
629 return 0;
Glauber Costab7454ad2012-10-19 18:20:25 +0400630}
631
Glauber Costa749c5412012-12-18 14:23:01 -0800632static int s_show(struct seq_file *m, void *p)
633{
634 struct kmem_cache *s = list_entry(p, struct kmem_cache, list);
635
636 if (!is_root_cache(s))
637 return 0;
638 return cache_show(s, m);
639}
640
Glauber Costab7454ad2012-10-19 18:20:25 +0400641/*
642 * slabinfo_op - iterator that generates /proc/slabinfo
643 *
644 * Output layout:
645 * cache-name
646 * num-active-objs
647 * total-objs
648 * object size
649 * num-active-slabs
650 * total-slabs
651 * num-pages-per-slab
652 * + further values on SMP and with statistics enabled
653 */
654static const struct seq_operations slabinfo_op = {
655 .start = s_start,
Wanpeng Li276a2432013-07-08 08:08:28 +0800656 .next = slab_next,
657 .stop = slab_stop,
Glauber Costab7454ad2012-10-19 18:20:25 +0400658 .show = s_show,
659};
660
661static int slabinfo_open(struct inode *inode, struct file *file)
662{
663 return seq_open(file, &slabinfo_op);
664}
665
666static const struct file_operations proc_slabinfo_operations = {
667 .open = slabinfo_open,
668 .read = seq_read,
669 .write = slabinfo_write,
670 .llseek = seq_lseek,
671 .release = seq_release,
672};
673
674static int __init slab_proc_init(void)
675{
Wanpeng Lie9b4db22013-07-04 08:33:24 +0800676 proc_create("slabinfo", SLABINFO_RIGHTS, NULL,
677 &proc_slabinfo_operations);
Glauber Costab7454ad2012-10-19 18:20:25 +0400678 return 0;
679}
680module_init(slab_proc_init);
681#endif /* CONFIG_SLABINFO */