2 * Slab allocator functions that are independent of the allocator strategy
4 * (C) 2012 Christoph Lameter <cl@linux.com>
6 #include <linux/slab.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>
14 #include <linux/cpu.h>
15 #include <linux/uaccess.h>
16 #include <linux/seq_file.h>
17 #include <linux/proc_fs.h>
18 #include <asm/cacheflush.h>
19 #include <asm/tlbflush.h>
21 #include <linux/memcontrol.h>
23 #define CREATE_TRACE_POINTS
24 #include <trace/events/kmem.h>
28 enum slab_state slab_state
;
29 LIST_HEAD(slab_caches
);
30 DEFINE_MUTEX(slab_mutex
);
31 struct kmem_cache
*kmem_cache
;
34 * Set of flags that will prevent slab merging
36 #define SLAB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
37 SLAB_TRACE | SLAB_DESTROY_BY_RCU | SLAB_NOLEAKTRACE | \
40 #define SLAB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \
41 SLAB_CACHE_DMA | SLAB_NOTRACK)
44 * Merge control. If this is set then no merging of slab caches will occur.
45 * (Could be removed. This was introduced to pacify the merge skeptics.)
47 static int slab_nomerge
;
49 static int __init
setup_slab_nomerge(char *str
)
56 __setup_param("slub_nomerge", slub_nomerge
, setup_slab_nomerge
, 0);
59 __setup("slab_nomerge", setup_slab_nomerge
);
62 * Determine the size of a slab object
64 unsigned int kmem_cache_size(struct kmem_cache
*s
)
66 return s
->object_size
;
68 EXPORT_SYMBOL(kmem_cache_size
);
70 #ifdef CONFIG_DEBUG_VM
71 static int kmem_cache_sanity_check(const char *name
, size_t size
)
73 struct kmem_cache
*s
= NULL
;
75 if (!name
|| in_interrupt() || size
< sizeof(void *) ||
76 size
> KMALLOC_MAX_SIZE
) {
77 pr_err("kmem_cache_create(%s) integrity check failed\n", name
);
81 list_for_each_entry(s
, &slab_caches
, list
) {
86 * This happens when the module gets unloaded and doesn't
87 * destroy its slab cache and no-one else reuses the vmalloc
88 * area of the module. Print a warning.
90 res
= probe_kernel_address(s
->name
, tmp
);
92 pr_err("Slab cache with size %d has lost its name\n",
98 WARN_ON(strchr(name
, ' ')); /* It confuses parsers */
102 static inline int kmem_cache_sanity_check(const char *name
, size_t size
)
108 #ifdef CONFIG_MEMCG_KMEM
109 void slab_init_memcg_params(struct kmem_cache
*s
)
111 s
->memcg_params
.is_root_cache
= true;
112 INIT_LIST_HEAD(&s
->memcg_params
.list
);
113 RCU_INIT_POINTER(s
->memcg_params
.memcg_caches
, NULL
);
116 static int init_memcg_params(struct kmem_cache
*s
,
117 struct mem_cgroup
*memcg
, struct kmem_cache
*root_cache
)
119 struct memcg_cache_array
*arr
;
122 s
->memcg_params
.is_root_cache
= false;
123 s
->memcg_params
.memcg
= memcg
;
124 s
->memcg_params
.root_cache
= root_cache
;
128 slab_init_memcg_params(s
);
130 if (!memcg_nr_cache_ids
)
133 arr
= kzalloc(sizeof(struct memcg_cache_array
) +
134 memcg_nr_cache_ids
* sizeof(void *),
139 RCU_INIT_POINTER(s
->memcg_params
.memcg_caches
, arr
);
143 static void destroy_memcg_params(struct kmem_cache
*s
)
145 if (is_root_cache(s
))
146 kfree(rcu_access_pointer(s
->memcg_params
.memcg_caches
));
149 static int update_memcg_params(struct kmem_cache
*s
, int new_array_size
)
151 struct memcg_cache_array
*old
, *new;
153 if (!is_root_cache(s
))
156 new = kzalloc(sizeof(struct memcg_cache_array
) +
157 new_array_size
* sizeof(void *), GFP_KERNEL
);
161 old
= rcu_dereference_protected(s
->memcg_params
.memcg_caches
,
162 lockdep_is_held(&slab_mutex
));
164 memcpy(new->entries
, old
->entries
,
165 memcg_nr_cache_ids
* sizeof(void *));
167 rcu_assign_pointer(s
->memcg_params
.memcg_caches
, new);
173 int memcg_update_all_caches(int num_memcgs
)
175 struct kmem_cache
*s
;
178 mutex_lock(&slab_mutex
);
179 list_for_each_entry(s
, &slab_caches
, list
) {
180 ret
= update_memcg_params(s
, num_memcgs
);
182 * Instead of freeing the memory, we'll just leave the caches
183 * up to this point in an updated state.
188 mutex_unlock(&slab_mutex
);
192 static inline int init_memcg_params(struct kmem_cache
*s
,
193 struct mem_cgroup
*memcg
, struct kmem_cache
*root_cache
)
198 static inline void destroy_memcg_params(struct kmem_cache
*s
)
201 #endif /* CONFIG_MEMCG_KMEM */
204 * Find a mergeable slab cache
206 int slab_unmergeable(struct kmem_cache
*s
)
208 if (slab_nomerge
|| (s
->flags
& SLAB_NEVER_MERGE
))
211 if (!is_root_cache(s
))
218 * We may have set a slab to be unmergeable during bootstrap.
226 struct kmem_cache
*find_mergeable(size_t size
, size_t align
,
227 unsigned long flags
, const char *name
, void (*ctor
)(void *))
229 struct kmem_cache
*s
;
231 if (slab_nomerge
|| (flags
& SLAB_NEVER_MERGE
))
237 size
= ALIGN(size
, sizeof(void *));
238 align
= calculate_alignment(flags
, align
, size
);
239 size
= ALIGN(size
, align
);
240 flags
= kmem_cache_flags(size
, flags
, name
, NULL
);
242 list_for_each_entry_reverse(s
, &slab_caches
, list
) {
243 if (slab_unmergeable(s
))
249 if ((flags
& SLAB_MERGE_SAME
) != (s
->flags
& SLAB_MERGE_SAME
))
252 * Check if alignment is compatible.
253 * Courtesy of Adrian Drzewiecki
255 if ((s
->size
& ~(align
- 1)) != s
->size
)
258 if (s
->size
- size
>= sizeof(void *))
261 if (IS_ENABLED(CONFIG_SLAB
) && align
&&
262 (align
> s
->align
|| s
->align
% align
))
271 * Figure out what the alignment of the objects will be given a set of
272 * flags, a user specified alignment and the size of the objects.
274 unsigned long calculate_alignment(unsigned long flags
,
275 unsigned long align
, unsigned long size
)
278 * If the user wants hardware cache aligned objects then follow that
279 * suggestion if the object is sufficiently large.
281 * The hardware cache alignment cannot override the specified
282 * alignment though. If that is greater then use it.
284 if (flags
& SLAB_HWCACHE_ALIGN
) {
285 unsigned long ralign
= cache_line_size();
286 while (size
<= ralign
/ 2)
288 align
= max(align
, ralign
);
291 if (align
< ARCH_SLAB_MINALIGN
)
292 align
= ARCH_SLAB_MINALIGN
;
294 return ALIGN(align
, sizeof(void *));
297 static struct kmem_cache
*
298 do_kmem_cache_create(char *name
, size_t object_size
, size_t size
, size_t align
,
299 unsigned long flags
, void (*ctor
)(void *),
300 struct mem_cgroup
*memcg
, struct kmem_cache
*root_cache
)
302 struct kmem_cache
*s
;
306 s
= kmem_cache_zalloc(kmem_cache
, GFP_KERNEL
);
311 s
->object_size
= object_size
;
316 err
= init_memcg_params(s
, memcg
, root_cache
);
320 err
= __kmem_cache_create(s
, flags
);
325 list_add(&s
->list
, &slab_caches
);
332 destroy_memcg_params(s
);
333 kmem_cache_free(kmem_cache
, s
);
338 * kmem_cache_create - Create a cache.
339 * @name: A string which is used in /proc/slabinfo to identify this cache.
340 * @size: The size of objects to be created in this cache.
341 * @align: The required alignment for the objects.
343 * @ctor: A constructor for the objects.
345 * Returns a ptr to the cache on success, NULL on failure.
346 * Cannot be called within a interrupt, but can be interrupted.
347 * The @ctor is run when new pages are allocated by the cache.
351 * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5)
352 * to catch references to uninitialised memory.
354 * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check
355 * for buffer overruns.
357 * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware
358 * cacheline. This can be beneficial if you're counting cycles as closely
362 kmem_cache_create(const char *name
, size_t size
, size_t align
,
363 unsigned long flags
, void (*ctor
)(void *))
365 struct kmem_cache
*s
;
371 memcg_get_cache_ids();
373 mutex_lock(&slab_mutex
);
375 err
= kmem_cache_sanity_check(name
, size
);
377 s
= NULL
; /* suppress uninit var warning */
382 * Some allocators will constraint the set of valid flags to a subset
383 * of all flags. We expect them to define CACHE_CREATE_MASK in this
384 * case, and we'll just provide them with a sanitized version of the
387 flags
&= CACHE_CREATE_MASK
;
389 s
= __kmem_cache_alias(name
, size
, align
, flags
, ctor
);
393 cache_name
= kstrdup(name
, GFP_KERNEL
);
399 s
= do_kmem_cache_create(cache_name
, size
, size
,
400 calculate_alignment(flags
, align
, size
),
401 flags
, ctor
, NULL
, NULL
);
408 mutex_unlock(&slab_mutex
);
410 memcg_put_cache_ids();
415 if (flags
& SLAB_PANIC
)
416 panic("kmem_cache_create: Failed to create slab '%s'. Error %d\n",
419 printk(KERN_WARNING
"kmem_cache_create(%s) failed with error %d",
427 EXPORT_SYMBOL(kmem_cache_create
);
429 static int do_kmem_cache_shutdown(struct kmem_cache
*s
,
430 struct list_head
*release
, bool *need_rcu_barrier
)
432 if (__kmem_cache_shutdown(s
) != 0) {
433 printk(KERN_ERR
"kmem_cache_destroy %s: "
434 "Slab cache still has objects\n", s
->name
);
439 if (s
->flags
& SLAB_DESTROY_BY_RCU
)
440 *need_rcu_barrier
= true;
442 #ifdef CONFIG_MEMCG_KMEM
443 if (!is_root_cache(s
)) {
445 struct memcg_cache_array
*arr
;
447 idx
= memcg_cache_id(s
->memcg_params
.memcg
);
448 arr
= rcu_dereference_protected(s
->memcg_params
.root_cache
->
449 memcg_params
.memcg_caches
,
450 lockdep_is_held(&slab_mutex
));
451 BUG_ON(arr
->entries
[idx
] != s
);
452 arr
->entries
[idx
] = NULL
;
453 list_del(&s
->memcg_params
.list
);
456 list_move(&s
->list
, release
);
460 static void do_kmem_cache_release(struct list_head
*release
,
461 bool need_rcu_barrier
)
463 struct kmem_cache
*s
, *s2
;
465 if (need_rcu_barrier
)
468 list_for_each_entry_safe(s
, s2
, release
, list
) {
469 #ifdef SLAB_SUPPORTS_SYSFS
470 sysfs_slab_remove(s
);
472 slab_kmem_cache_release(s
);
477 #ifdef CONFIG_MEMCG_KMEM
479 * memcg_create_kmem_cache - Create a cache for a memory cgroup.
480 * @memcg: The memory cgroup the new cache is for.
481 * @root_cache: The parent of the new cache.
483 * This function attempts to create a kmem cache that will serve allocation
484 * requests going from @memcg to @root_cache. The new cache inherits properties
487 void memcg_create_kmem_cache(struct mem_cgroup
*memcg
,
488 struct kmem_cache
*root_cache
)
490 static char memcg_name_buf
[NAME_MAX
+ 1]; /* protected by slab_mutex */
491 struct cgroup_subsys_state
*css
= mem_cgroup_css(memcg
);
492 struct memcg_cache_array
*arr
;
493 struct kmem_cache
*s
= NULL
;
500 mutex_lock(&slab_mutex
);
502 idx
= memcg_cache_id(memcg
);
503 arr
= rcu_dereference_protected(root_cache
->memcg_params
.memcg_caches
,
504 lockdep_is_held(&slab_mutex
));
507 * Since per-memcg caches are created asynchronously on first
508 * allocation (see memcg_kmem_get_cache()), several threads can try to
509 * create the same cache, but only one of them may succeed.
511 if (arr
->entries
[idx
])
514 cgroup_name(css
->cgroup
, memcg_name_buf
, sizeof(memcg_name_buf
));
515 cache_name
= kasprintf(GFP_KERNEL
, "%s(%d:%s)", root_cache
->name
,
516 css
->id
, memcg_name_buf
);
520 s
= do_kmem_cache_create(cache_name
, root_cache
->object_size
,
521 root_cache
->size
, root_cache
->align
,
522 root_cache
->flags
, root_cache
->ctor
,
525 * If we could not create a memcg cache, do not complain, because
526 * that's not critical at all as we can always proceed with the root
534 list_add(&s
->memcg_params
.list
, &root_cache
->memcg_params
.list
);
537 * Since readers won't lock (see cache_from_memcg_idx()), we need a
538 * barrier here to ensure nobody will see the kmem_cache partially
542 arr
->entries
[idx
] = s
;
545 mutex_unlock(&slab_mutex
);
551 void memcg_destroy_kmem_caches(struct mem_cgroup
*memcg
)
554 bool need_rcu_barrier
= false;
555 struct kmem_cache
*s
, *s2
;
560 mutex_lock(&slab_mutex
);
561 list_for_each_entry_safe(s
, s2
, &slab_caches
, list
) {
562 if (is_root_cache(s
) || s
->memcg_params
.memcg
!= memcg
)
565 * The cgroup is about to be freed and therefore has no charges
566 * left. Hence, all its caches must be empty by now.
568 BUG_ON(do_kmem_cache_shutdown(s
, &release
, &need_rcu_barrier
));
570 mutex_unlock(&slab_mutex
);
575 do_kmem_cache_release(&release
, need_rcu_barrier
);
577 #endif /* CONFIG_MEMCG_KMEM */
579 void slab_kmem_cache_release(struct kmem_cache
*s
)
581 destroy_memcg_params(s
);
583 kmem_cache_free(kmem_cache
, s
);
586 void kmem_cache_destroy(struct kmem_cache
*s
)
588 struct kmem_cache
*c
, *c2
;
590 bool need_rcu_barrier
= false;
593 BUG_ON(!is_root_cache(s
));
598 mutex_lock(&slab_mutex
);
604 for_each_memcg_cache_safe(c
, c2
, s
) {
605 if (do_kmem_cache_shutdown(c
, &release
, &need_rcu_barrier
))
610 do_kmem_cache_shutdown(s
, &release
, &need_rcu_barrier
);
613 mutex_unlock(&slab_mutex
);
618 do_kmem_cache_release(&release
, need_rcu_barrier
);
620 EXPORT_SYMBOL(kmem_cache_destroy
);
623 * kmem_cache_shrink - Shrink a cache.
624 * @cachep: The cache to shrink.
626 * Releases as many slabs as possible for a cache.
627 * To help debugging, a zero exit status indicates all slabs were released.
629 int kmem_cache_shrink(struct kmem_cache
*cachep
)
635 ret
= __kmem_cache_shrink(cachep
);
640 EXPORT_SYMBOL(kmem_cache_shrink
);
642 int slab_is_available(void)
644 return slab_state
>= UP
;
648 /* Create a cache during boot when no slab services are available yet */
649 void __init
create_boot_cache(struct kmem_cache
*s
, const char *name
, size_t size
,
655 s
->size
= s
->object_size
= size
;
656 s
->align
= calculate_alignment(flags
, ARCH_KMALLOC_MINALIGN
, size
);
658 slab_init_memcg_params(s
);
660 err
= __kmem_cache_create(s
, flags
);
663 panic("Creation of kmalloc slab %s size=%zu failed. Reason %d\n",
666 s
->refcount
= -1; /* Exempt from merging for now */
669 struct kmem_cache
*__init
create_kmalloc_cache(const char *name
, size_t size
,
672 struct kmem_cache
*s
= kmem_cache_zalloc(kmem_cache
, GFP_NOWAIT
);
675 panic("Out of memory when creating slab %s\n", name
);
677 create_boot_cache(s
, name
, size
, flags
);
678 list_add(&s
->list
, &slab_caches
);
683 struct kmem_cache
*kmalloc_caches
[KMALLOC_SHIFT_HIGH
+ 1];
684 EXPORT_SYMBOL(kmalloc_caches
);
686 #ifdef CONFIG_ZONE_DMA
687 struct kmem_cache
*kmalloc_dma_caches
[KMALLOC_SHIFT_HIGH
+ 1];
688 EXPORT_SYMBOL(kmalloc_dma_caches
);
692 * Conversion table for small slabs sizes / 8 to the index in the
693 * kmalloc array. This is necessary for slabs < 192 since we have non power
694 * of two cache sizes there. The size of larger slabs can be determined using
697 static s8 size_index
[24] = {
724 static inline int size_index_elem(size_t bytes
)
726 return (bytes
- 1) / 8;
730 * Find the kmem_cache structure that serves a given size of
733 struct kmem_cache
*kmalloc_slab(size_t size
, gfp_t flags
)
737 if (unlikely(size
> KMALLOC_MAX_SIZE
)) {
738 WARN_ON_ONCE(!(flags
& __GFP_NOWARN
));
744 return ZERO_SIZE_PTR
;
746 index
= size_index
[size_index_elem(size
)];
748 index
= fls(size
- 1);
750 #ifdef CONFIG_ZONE_DMA
751 if (unlikely((flags
& GFP_DMA
)))
752 return kmalloc_dma_caches
[index
];
755 return kmalloc_caches
[index
];
759 * Create the kmalloc array. Some of the regular kmalloc arrays
760 * may already have been created because they were needed to
761 * enable allocations for slab creation.
763 void __init
create_kmalloc_caches(unsigned long flags
)
768 * Patch up the size_index table if we have strange large alignment
769 * requirements for the kmalloc array. This is only the case for
770 * MIPS it seems. The standard arches will not generate any code here.
772 * Largest permitted alignment is 256 bytes due to the way we
773 * handle the index determination for the smaller caches.
775 * Make sure that nothing crazy happens if someone starts tinkering
776 * around with ARCH_KMALLOC_MINALIGN
778 BUILD_BUG_ON(KMALLOC_MIN_SIZE
> 256 ||
779 (KMALLOC_MIN_SIZE
& (KMALLOC_MIN_SIZE
- 1)));
781 for (i
= 8; i
< KMALLOC_MIN_SIZE
; i
+= 8) {
782 int elem
= size_index_elem(i
);
784 if (elem
>= ARRAY_SIZE(size_index
))
786 size_index
[elem
] = KMALLOC_SHIFT_LOW
;
789 if (KMALLOC_MIN_SIZE
>= 64) {
791 * The 96 byte size cache is not used if the alignment
794 for (i
= 64 + 8; i
<= 96; i
+= 8)
795 size_index
[size_index_elem(i
)] = 7;
799 if (KMALLOC_MIN_SIZE
>= 128) {
801 * The 192 byte sized cache is not used if the alignment
802 * is 128 byte. Redirect kmalloc to use the 256 byte cache
805 for (i
= 128 + 8; i
<= 192; i
+= 8)
806 size_index
[size_index_elem(i
)] = 8;
808 for (i
= KMALLOC_SHIFT_LOW
; i
<= KMALLOC_SHIFT_HIGH
; i
++) {
809 if (!kmalloc_caches
[i
]) {
810 kmalloc_caches
[i
] = create_kmalloc_cache(NULL
,
815 * Caches that are not of the two-to-the-power-of size.
816 * These have to be created immediately after the
817 * earlier power of two caches
819 if (KMALLOC_MIN_SIZE
<= 32 && !kmalloc_caches
[1] && i
== 6)
820 kmalloc_caches
[1] = create_kmalloc_cache(NULL
, 96, flags
);
822 if (KMALLOC_MIN_SIZE
<= 64 && !kmalloc_caches
[2] && i
== 7)
823 kmalloc_caches
[2] = create_kmalloc_cache(NULL
, 192, flags
);
826 /* Kmalloc array is now usable */
829 for (i
= 0; i
<= KMALLOC_SHIFT_HIGH
; i
++) {
830 struct kmem_cache
*s
= kmalloc_caches
[i
];
834 n
= kasprintf(GFP_NOWAIT
, "kmalloc-%d", kmalloc_size(i
));
841 #ifdef CONFIG_ZONE_DMA
842 for (i
= 0; i
<= KMALLOC_SHIFT_HIGH
; i
++) {
843 struct kmem_cache
*s
= kmalloc_caches
[i
];
846 int size
= kmalloc_size(i
);
847 char *n
= kasprintf(GFP_NOWAIT
,
848 "dma-kmalloc-%d", size
);
851 kmalloc_dma_caches
[i
] = create_kmalloc_cache(n
,
852 size
, SLAB_CACHE_DMA
| flags
);
857 #endif /* !CONFIG_SLOB */
860 * To avoid unnecessary overhead, we pass through large allocation requests
861 * directly to the page allocator. We use __GFP_COMP, because we will need to
862 * know the allocation order to free the pages properly in kfree.
864 void *kmalloc_order(size_t size
, gfp_t flags
, unsigned int order
)
870 page
= alloc_kmem_pages(flags
, order
);
871 ret
= page
? page_address(page
) : NULL
;
872 kmemleak_alloc(ret
, size
, 1, flags
);
875 EXPORT_SYMBOL(kmalloc_order
);
877 #ifdef CONFIG_TRACING
878 void *kmalloc_order_trace(size_t size
, gfp_t flags
, unsigned int order
)
880 void *ret
= kmalloc_order(size
, flags
, order
);
881 trace_kmalloc(_RET_IP_
, ret
, size
, PAGE_SIZE
<< order
, flags
);
884 EXPORT_SYMBOL(kmalloc_order_trace
);
887 #ifdef CONFIG_SLABINFO
890 #define SLABINFO_RIGHTS (S_IWUSR | S_IRUSR)
892 #define SLABINFO_RIGHTS S_IRUSR
895 static void print_slabinfo_header(struct seq_file
*m
)
898 * Output format version, so at least we can change it
899 * without _too_ many complaints.
901 #ifdef CONFIG_DEBUG_SLAB
902 seq_puts(m
, "slabinfo - version: 2.1 (statistics)\n");
904 seq_puts(m
, "slabinfo - version: 2.1\n");
906 seq_puts(m
, "# name <active_objs> <num_objs> <objsize> "
907 "<objperslab> <pagesperslab>");
908 seq_puts(m
, " : tunables <limit> <batchcount> <sharedfactor>");
909 seq_puts(m
, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
910 #ifdef CONFIG_DEBUG_SLAB
911 seq_puts(m
, " : globalstat <listallocs> <maxobjs> <grown> <reaped> "
912 "<error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>");
913 seq_puts(m
, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>");
918 void *slab_start(struct seq_file
*m
, loff_t
*pos
)
920 mutex_lock(&slab_mutex
);
921 return seq_list_start(&slab_caches
, *pos
);
924 void *slab_next(struct seq_file
*m
, void *p
, loff_t
*pos
)
926 return seq_list_next(p
, &slab_caches
, pos
);
929 void slab_stop(struct seq_file
*m
, void *p
)
931 mutex_unlock(&slab_mutex
);
935 memcg_accumulate_slabinfo(struct kmem_cache
*s
, struct slabinfo
*info
)
937 struct kmem_cache
*c
;
938 struct slabinfo sinfo
;
940 if (!is_root_cache(s
))
943 for_each_memcg_cache(c
, s
) {
944 memset(&sinfo
, 0, sizeof(sinfo
));
945 get_slabinfo(c
, &sinfo
);
947 info
->active_slabs
+= sinfo
.active_slabs
;
948 info
->num_slabs
+= sinfo
.num_slabs
;
949 info
->shared_avail
+= sinfo
.shared_avail
;
950 info
->active_objs
+= sinfo
.active_objs
;
951 info
->num_objs
+= sinfo
.num_objs
;
955 static void cache_show(struct kmem_cache
*s
, struct seq_file
*m
)
957 struct slabinfo sinfo
;
959 memset(&sinfo
, 0, sizeof(sinfo
));
960 get_slabinfo(s
, &sinfo
);
962 memcg_accumulate_slabinfo(s
, &sinfo
);
964 seq_printf(m
, "%-17s %6lu %6lu %6u %4u %4d",
965 cache_name(s
), sinfo
.active_objs
, sinfo
.num_objs
, s
->size
,
966 sinfo
.objects_per_slab
, (1 << sinfo
.cache_order
));
968 seq_printf(m
, " : tunables %4u %4u %4u",
969 sinfo
.limit
, sinfo
.batchcount
, sinfo
.shared
);
970 seq_printf(m
, " : slabdata %6lu %6lu %6lu",
971 sinfo
.active_slabs
, sinfo
.num_slabs
, sinfo
.shared_avail
);
972 slabinfo_show_stats(m
, s
);
976 static int slab_show(struct seq_file
*m
, void *p
)
978 struct kmem_cache
*s
= list_entry(p
, struct kmem_cache
, list
);
980 if (p
== slab_caches
.next
)
981 print_slabinfo_header(m
);
982 if (is_root_cache(s
))
987 #ifdef CONFIG_MEMCG_KMEM
988 int memcg_slab_show(struct seq_file
*m
, void *p
)
990 struct kmem_cache
*s
= list_entry(p
, struct kmem_cache
, list
);
991 struct mem_cgroup
*memcg
= mem_cgroup_from_css(seq_css(m
));
993 if (p
== slab_caches
.next
)
994 print_slabinfo_header(m
);
995 if (!is_root_cache(s
) && s
->memcg_params
.memcg
== memcg
)
1002 * slabinfo_op - iterator that generates /proc/slabinfo
1011 * num-pages-per-slab
1012 * + further values on SMP and with statistics enabled
1014 static const struct seq_operations slabinfo_op
= {
1015 .start
= slab_start
,
1021 static int slabinfo_open(struct inode
*inode
, struct file
*file
)
1023 return seq_open(file
, &slabinfo_op
);
1026 static const struct file_operations proc_slabinfo_operations
= {
1027 .open
= slabinfo_open
,
1029 .write
= slabinfo_write
,
1030 .llseek
= seq_lseek
,
1031 .release
= seq_release
,
1034 static int __init
slab_proc_init(void)
1036 proc_create("slabinfo", SLABINFO_RIGHTS
, NULL
,
1037 &proc_slabinfo_operations
);
1040 module_init(slab_proc_init
);
1041 #endif /* CONFIG_SLABINFO */
1043 static __always_inline
void *__do_krealloc(const void *p
, size_t new_size
,
1055 ret
= kmalloc_track_caller(new_size
, flags
);
1063 * __krealloc - like krealloc() but don't free @p.
1064 * @p: object to reallocate memory for.
1065 * @new_size: how many bytes of memory are required.
1066 * @flags: the type of memory to allocate.
1068 * This function is like krealloc() except it never frees the originally
1069 * allocated buffer. Use this if you don't want to free the buffer immediately
1070 * like, for example, with RCU.
1072 void *__krealloc(const void *p
, size_t new_size
, gfp_t flags
)
1074 if (unlikely(!new_size
))
1075 return ZERO_SIZE_PTR
;
1077 return __do_krealloc(p
, new_size
, flags
);
1080 EXPORT_SYMBOL(__krealloc
);
1083 * krealloc - reallocate memory. The contents will remain unchanged.
1084 * @p: object to reallocate memory for.
1085 * @new_size: how many bytes of memory are required.
1086 * @flags: the type of memory to allocate.
1088 * The contents of the object pointed to are preserved up to the
1089 * lesser of the new and old sizes. If @p is %NULL, krealloc()
1090 * behaves exactly like kmalloc(). If @new_size is 0 and @p is not a
1091 * %NULL pointer, the object pointed to is freed.
1093 void *krealloc(const void *p
, size_t new_size
, gfp_t flags
)
1097 if (unlikely(!new_size
)) {
1099 return ZERO_SIZE_PTR
;
1102 ret
= __do_krealloc(p
, new_size
, flags
);
1103 if (ret
&& p
!= ret
)
1108 EXPORT_SYMBOL(krealloc
);
1111 * kzfree - like kfree but zero memory
1112 * @p: object to free memory of
1114 * The memory of the object @p points to is zeroed before freed.
1115 * If @p is %NULL, kzfree() does nothing.
1117 * Note: this function zeroes the whole allocated buffer which can be a good
1118 * deal bigger than the requested buffer size passed to kmalloc(). So be
1119 * careful when using this function in performance sensitive code.
1121 void kzfree(const void *p
)
1124 void *mem
= (void *)p
;
1126 if (unlikely(ZERO_OR_NULL_PTR(mem
)))
1132 EXPORT_SYMBOL(kzfree
);
1134 /* Tracepoints definitions. */
1135 EXPORT_TRACEPOINT_SYMBOL(kmalloc
);
1136 EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc
);
1137 EXPORT_TRACEPOINT_SYMBOL(kmalloc_node
);
1138 EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc_node
);
1139 EXPORT_TRACEPOINT_SYMBOL(kfree
);
1140 EXPORT_TRACEPOINT_SYMBOL(kmem_cache_free
);