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TOMOYO Linux Cross Reference
Linux/include/linux/slab.h

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  1 /*
  2  * Written by Mark Hemment, 1996 (markhe@nextd.demon.co.uk).
  3  *
  4  * (C) SGI 2006, Christoph Lameter
  5  *      Cleaned up and restructured to ease the addition of alternative
  6  *      implementations of SLAB allocators.
  7  * (C) Linux Foundation 2008-2013
  8  *      Unified interface for all slab allocators
  9  */
 10 
 11 #ifndef _LINUX_SLAB_H
 12 #define _LINUX_SLAB_H
 13 
 14 #include <linux/gfp.h>
 15 #include <linux/types.h>
 16 #include <linux/workqueue.h>
 17 
 18 
 19 /*
 20  * Flags to pass to kmem_cache_create().
 21  * The ones marked DEBUG are only valid if CONFIG_SLAB_DEBUG is set.
 22  */
 23 #define SLAB_DEBUG_FREE         0x00000100UL    /* DEBUG: Perform (expensive) checks on free */
 24 #define SLAB_RED_ZONE           0x00000400UL    /* DEBUG: Red zone objs in a cache */
 25 #define SLAB_POISON             0x00000800UL    /* DEBUG: Poison objects */
 26 #define SLAB_HWCACHE_ALIGN      0x00002000UL    /* Align objs on cache lines */
 27 #define SLAB_CACHE_DMA          0x00004000UL    /* Use GFP_DMA memory */
 28 #define SLAB_STORE_USER         0x00010000UL    /* DEBUG: Store the last owner for bug hunting */
 29 #define SLAB_PANIC              0x00040000UL    /* Panic if kmem_cache_create() fails */
 30 /*
 31  * SLAB_DESTROY_BY_RCU - **WARNING** READ THIS!
 32  *
 33  * This delays freeing the SLAB page by a grace period, it does _NOT_
 34  * delay object freeing. This means that if you do kmem_cache_free()
 35  * that memory location is free to be reused at any time. Thus it may
 36  * be possible to see another object there in the same RCU grace period.
 37  *
 38  * This feature only ensures the memory location backing the object
 39  * stays valid, the trick to using this is relying on an independent
 40  * object validation pass. Something like:
 41  *
 42  *  rcu_read_lock()
 43  * again:
 44  *  obj = lockless_lookup(key);
 45  *  if (obj) {
 46  *    if (!try_get_ref(obj)) // might fail for free objects
 47  *      goto again;
 48  *
 49  *    if (obj->key != key) { // not the object we expected
 50  *      put_ref(obj);
 51  *      goto again;
 52  *    }
 53  *  }
 54  *  rcu_read_unlock();
 55  *
 56  * This is useful if we need to approach a kernel structure obliquely,
 57  * from its address obtained without the usual locking. We can lock
 58  * the structure to stabilize it and check it's still at the given address,
 59  * only if we can be sure that the memory has not been meanwhile reused
 60  * for some other kind of object (which our subsystem's lock might corrupt).
 61  *
 62  * rcu_read_lock before reading the address, then rcu_read_unlock after
 63  * taking the spinlock within the structure expected at that address.
 64  */
 65 #define SLAB_DESTROY_BY_RCU     0x00080000UL    /* Defer freeing slabs to RCU */
 66 #define SLAB_MEM_SPREAD         0x00100000UL    /* Spread some memory over cpuset */
 67 #define SLAB_TRACE              0x00200000UL    /* Trace allocations and frees */
 68 
 69 /* Flag to prevent checks on free */
 70 #ifdef CONFIG_DEBUG_OBJECTS
 71 # define SLAB_DEBUG_OBJECTS     0x00400000UL
 72 #else
 73 # define SLAB_DEBUG_OBJECTS     0x00000000UL
 74 #endif
 75 
 76 #define SLAB_NOLEAKTRACE        0x00800000UL    /* Avoid kmemleak tracing */
 77 
 78 /* Don't track use of uninitialized memory */
 79 #ifdef CONFIG_KMEMCHECK
 80 # define SLAB_NOTRACK           0x01000000UL
 81 #else
 82 # define SLAB_NOTRACK           0x00000000UL
 83 #endif
 84 #ifdef CONFIG_FAILSLAB
 85 # define SLAB_FAILSLAB          0x02000000UL    /* Fault injection mark */
 86 #else
 87 # define SLAB_FAILSLAB          0x00000000UL
 88 #endif
 89 
 90 /* The following flags affect the page allocator grouping pages by mobility */
 91 #define SLAB_RECLAIM_ACCOUNT    0x00020000UL            /* Objects are reclaimable */
 92 #define SLAB_TEMPORARY          SLAB_RECLAIM_ACCOUNT    /* Objects are short-lived */
 93 /*
 94  * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests.
 95  *
 96  * Dereferencing ZERO_SIZE_PTR will lead to a distinct access fault.
 97  *
 98  * ZERO_SIZE_PTR can be passed to kfree though in the same way that NULL can.
 99  * Both make kfree a no-op.
100  */
101 #define ZERO_SIZE_PTR ((void *)16)
102 
103 #define ZERO_OR_NULL_PTR(x) ((unsigned long)(x) <= \
104                                 (unsigned long)ZERO_SIZE_PTR)
105 
106 #include <linux/kmemleak.h>
107 
108 struct mem_cgroup;
109 /*
110  * struct kmem_cache related prototypes
111  */
112 void __init kmem_cache_init(void);
113 int slab_is_available(void);
114 
115 struct kmem_cache *kmem_cache_create(const char *, size_t, size_t,
116                         unsigned long,
117                         void (*)(void *));
118 #ifdef CONFIG_MEMCG_KMEM
119 void kmem_cache_create_memcg(struct mem_cgroup *, struct kmem_cache *);
120 #endif
121 void kmem_cache_destroy(struct kmem_cache *);
122 int kmem_cache_shrink(struct kmem_cache *);
123 void kmem_cache_free(struct kmem_cache *, void *);
124 
125 /*
126  * Please use this macro to create slab caches. Simply specify the
127  * name of the structure and maybe some flags that are listed above.
128  *
129  * The alignment of the struct determines object alignment. If you
130  * f.e. add ____cacheline_aligned_in_smp to the struct declaration
131  * then the objects will be properly aligned in SMP configurations.
132  */
133 #define KMEM_CACHE(__struct, __flags) kmem_cache_create(#__struct,\
134                 sizeof(struct __struct), __alignof__(struct __struct),\
135                 (__flags), NULL)
136 
137 /*
138  * Common kmalloc functions provided by all allocators
139  */
140 void * __must_check __krealloc(const void *, size_t, gfp_t);
141 void * __must_check krealloc(const void *, size_t, gfp_t);
142 void kfree(const void *);
143 void kzfree(const void *);
144 size_t ksize(const void *);
145 
146 /*
147  * Some archs want to perform DMA into kmalloc caches and need a guaranteed
148  * alignment larger than the alignment of a 64-bit integer.
149  * Setting ARCH_KMALLOC_MINALIGN in arch headers allows that.
150  */
151 #if defined(ARCH_DMA_MINALIGN) && ARCH_DMA_MINALIGN > 8
152 #define ARCH_KMALLOC_MINALIGN ARCH_DMA_MINALIGN
153 #define KMALLOC_MIN_SIZE ARCH_DMA_MINALIGN
154 #define KMALLOC_SHIFT_LOW ilog2(ARCH_DMA_MINALIGN)
155 #else
156 #define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
157 #endif
158 
159 #ifdef CONFIG_SLOB
160 /*
161  * Common fields provided in kmem_cache by all slab allocators
162  * This struct is either used directly by the allocator (SLOB)
163  * or the allocator must include definitions for all fields
164  * provided in kmem_cache_common in their definition of kmem_cache.
165  *
166  * Once we can do anonymous structs (C11 standard) we could put a
167  * anonymous struct definition in these allocators so that the
168  * separate allocations in the kmem_cache structure of SLAB and
169  * SLUB is no longer needed.
170  */
171 struct kmem_cache {
172         unsigned int object_size;/* The original size of the object */
173         unsigned int size;      /* The aligned/padded/added on size  */
174         unsigned int align;     /* Alignment as calculated */
175         unsigned long flags;    /* Active flags on the slab */
176         const char *name;       /* Slab name for sysfs */
177         int refcount;           /* Use counter */
178         void (*ctor)(void *);   /* Called on object slot creation */
179         struct list_head list;  /* List of all slab caches on the system */
180 };
181 
182 #endif /* CONFIG_SLOB */
183 
184 /*
185  * Kmalloc array related definitions
186  */
187 
188 #ifdef CONFIG_SLAB
189 /*
190  * The largest kmalloc size supported by the SLAB allocators is
191  * 32 megabyte (2^25) or the maximum allocatable page order if that is
192  * less than 32 MB.
193  *
194  * WARNING: Its not easy to increase this value since the allocators have
195  * to do various tricks to work around compiler limitations in order to
196  * ensure proper constant folding.
197  */
198 #define KMALLOC_SHIFT_HIGH      ((MAX_ORDER + PAGE_SHIFT - 1) <= 25 ? \
199                                 (MAX_ORDER + PAGE_SHIFT - 1) : 25)
200 #define KMALLOC_SHIFT_MAX       KMALLOC_SHIFT_HIGH
201 #ifndef KMALLOC_SHIFT_LOW
202 #define KMALLOC_SHIFT_LOW       5
203 #endif
204 #endif
205 
206 #ifdef CONFIG_SLUB
207 /*
208  * SLUB directly allocates requests fitting in to an order-1 page
209  * (PAGE_SIZE*2).  Larger requests are passed to the page allocator.
210  */
211 #define KMALLOC_SHIFT_HIGH      (PAGE_SHIFT + 1)
212 #define KMALLOC_SHIFT_MAX       (MAX_ORDER + PAGE_SHIFT)
213 #ifndef KMALLOC_SHIFT_LOW
214 #define KMALLOC_SHIFT_LOW       3
215 #endif
216 #endif
217 
218 #ifdef CONFIG_SLOB
219 /*
220  * SLOB passes all requests larger than one page to the page allocator.
221  * No kmalloc array is necessary since objects of different sizes can
222  * be allocated from the same page.
223  */
224 #define KMALLOC_SHIFT_HIGH      PAGE_SHIFT
225 #define KMALLOC_SHIFT_MAX       30
226 #ifndef KMALLOC_SHIFT_LOW
227 #define KMALLOC_SHIFT_LOW       3
228 #endif
229 #endif
230 
231 /* Maximum allocatable size */
232 #define KMALLOC_MAX_SIZE        (1UL << KMALLOC_SHIFT_MAX)
233 /* Maximum size for which we actually use a slab cache */
234 #define KMALLOC_MAX_CACHE_SIZE  (1UL << KMALLOC_SHIFT_HIGH)
235 /* Maximum order allocatable via the slab allocagtor */
236 #define KMALLOC_MAX_ORDER       (KMALLOC_SHIFT_MAX - PAGE_SHIFT)
237 
238 /*
239  * Kmalloc subsystem.
240  */
241 #ifndef KMALLOC_MIN_SIZE
242 #define KMALLOC_MIN_SIZE (1 << KMALLOC_SHIFT_LOW)
243 #endif
244 
245 /*
246  * This restriction comes from byte sized index implementation.
247  * Page size is normally 2^12 bytes and, in this case, if we want to use
248  * byte sized index which can represent 2^8 entries, the size of the object
249  * should be equal or greater to 2^12 / 2^8 = 2^4 = 16.
250  * If minimum size of kmalloc is less than 16, we use it as minimum object
251  * size and give up to use byte sized index.
252  */
253 #define SLAB_OBJ_MIN_SIZE      (KMALLOC_MIN_SIZE < 16 ? \
254                                (KMALLOC_MIN_SIZE) : 16)
255 
256 #ifndef CONFIG_SLOB
257 extern struct kmem_cache *kmalloc_caches[KMALLOC_SHIFT_HIGH + 1];
258 #ifdef CONFIG_ZONE_DMA
259 extern struct kmem_cache *kmalloc_dma_caches[KMALLOC_SHIFT_HIGH + 1];
260 #endif
261 
262 /*
263  * Figure out which kmalloc slab an allocation of a certain size
264  * belongs to.
265  * 0 = zero alloc
266  * 1 =  65 .. 96 bytes
267  * 2 = 120 .. 192 bytes
268  * n = 2^(n-1) .. 2^n -1
269  */
270 static __always_inline int kmalloc_index(size_t size)
271 {
272         if (!size)
273                 return 0;
274 
275         if (size <= KMALLOC_MIN_SIZE)
276                 return KMALLOC_SHIFT_LOW;
277 
278         if (KMALLOC_MIN_SIZE <= 32 && size > 64 && size <= 96)
279                 return 1;
280         if (KMALLOC_MIN_SIZE <= 64 && size > 128 && size <= 192)
281                 return 2;
282         if (size <=          8) return 3;
283         if (size <=         16) return 4;
284         if (size <=         32) return 5;
285         if (size <=         64) return 6;
286         if (size <=        128) return 7;
287         if (size <=        256) return 8;
288         if (size <=        512) return 9;
289         if (size <=       1024) return 10;
290         if (size <=   2 * 1024) return 11;
291         if (size <=   4 * 1024) return 12;
292         if (size <=   8 * 1024) return 13;
293         if (size <=  16 * 1024) return 14;
294         if (size <=  32 * 1024) return 15;
295         if (size <=  64 * 1024) return 16;
296         if (size <= 128 * 1024) return 17;
297         if (size <= 256 * 1024) return 18;
298         if (size <= 512 * 1024) return 19;
299         if (size <= 1024 * 1024) return 20;
300         if (size <=  2 * 1024 * 1024) return 21;
301         if (size <=  4 * 1024 * 1024) return 22;
302         if (size <=  8 * 1024 * 1024) return 23;
303         if (size <=  16 * 1024 * 1024) return 24;
304         if (size <=  32 * 1024 * 1024) return 25;
305         if (size <=  64 * 1024 * 1024) return 26;
306         BUG();
307 
308         /* Will never be reached. Needed because the compiler may complain */
309         return -1;
310 }
311 #endif /* !CONFIG_SLOB */
312 
313 void *__kmalloc(size_t size, gfp_t flags);
314 void *kmem_cache_alloc(struct kmem_cache *, gfp_t flags);
315 
316 #ifdef CONFIG_NUMA
317 void *__kmalloc_node(size_t size, gfp_t flags, int node);
318 void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
319 #else
320 static __always_inline void *__kmalloc_node(size_t size, gfp_t flags, int node)
321 {
322         return __kmalloc(size, flags);
323 }
324 
325 static __always_inline void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t flags, int node)
326 {
327         return kmem_cache_alloc(s, flags);
328 }
329 #endif
330 
331 #ifdef CONFIG_TRACING
332 extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t);
333 
334 #ifdef CONFIG_NUMA
335 extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
336                                            gfp_t gfpflags,
337                                            int node, size_t size);
338 #else
339 static __always_inline void *
340 kmem_cache_alloc_node_trace(struct kmem_cache *s,
341                               gfp_t gfpflags,
342                               int node, size_t size)
343 {
344         return kmem_cache_alloc_trace(s, gfpflags, size);
345 }
346 #endif /* CONFIG_NUMA */
347 
348 #else /* CONFIG_TRACING */
349 static __always_inline void *kmem_cache_alloc_trace(struct kmem_cache *s,
350                 gfp_t flags, size_t size)
351 {
352         return kmem_cache_alloc(s, flags);
353 }
354 
355 static __always_inline void *
356 kmem_cache_alloc_node_trace(struct kmem_cache *s,
357                               gfp_t gfpflags,
358                               int node, size_t size)
359 {
360         return kmem_cache_alloc_node(s, gfpflags, node);
361 }
362 #endif /* CONFIG_TRACING */
363 
364 #ifdef CONFIG_SLAB
365 #include <linux/slab_def.h>
366 #endif
367 
368 #ifdef CONFIG_SLUB
369 #include <linux/slub_def.h>
370 #endif
371 
372 static __always_inline void *
373 kmalloc_order(size_t size, gfp_t flags, unsigned int order)
374 {
375         void *ret;
376 
377         flags |= (__GFP_COMP | __GFP_KMEMCG);
378         ret = (void *) __get_free_pages(flags, order);
379         kmemleak_alloc(ret, size, 1, flags);
380         return ret;
381 }
382 
383 #ifdef CONFIG_TRACING
384 extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order);
385 #else
386 static __always_inline void *
387 kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
388 {
389         return kmalloc_order(size, flags, order);
390 }
391 #endif
392 
393 static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
394 {
395         unsigned int order = get_order(size);
396         return kmalloc_order_trace(size, flags, order);
397 }
398 
399 /**
400  * kmalloc - allocate memory
401  * @size: how many bytes of memory are required.
402  * @flags: the type of memory to allocate.
403  *
404  * kmalloc is the normal method of allocating memory
405  * for objects smaller than page size in the kernel.
406  *
407  * The @flags argument may be one of:
408  *
409  * %GFP_USER - Allocate memory on behalf of user.  May sleep.
410  *
411  * %GFP_KERNEL - Allocate normal kernel ram.  May sleep.
412  *
413  * %GFP_ATOMIC - Allocation will not sleep.  May use emergency pools.
414  *   For example, use this inside interrupt handlers.
415  *
416  * %GFP_HIGHUSER - Allocate pages from high memory.
417  *
418  * %GFP_NOIO - Do not do any I/O at all while trying to get memory.
419  *
420  * %GFP_NOFS - Do not make any fs calls while trying to get memory.
421  *
422  * %GFP_NOWAIT - Allocation will not sleep.
423  *
424  * %__GFP_THISNODE - Allocate node-local memory only.
425  *
426  * %GFP_DMA - Allocation suitable for DMA.
427  *   Should only be used for kmalloc() caches. Otherwise, use a
428  *   slab created with SLAB_DMA.
429  *
430  * Also it is possible to set different flags by OR'ing
431  * in one or more of the following additional @flags:
432  *
433  * %__GFP_COLD - Request cache-cold pages instead of
434  *   trying to return cache-warm pages.
435  *
436  * %__GFP_HIGH - This allocation has high priority and may use emergency pools.
437  *
438  * %__GFP_NOFAIL - Indicate that this allocation is in no way allowed to fail
439  *   (think twice before using).
440  *
441  * %__GFP_NORETRY - If memory is not immediately available,
442  *   then give up at once.
443  *
444  * %__GFP_NOWARN - If allocation fails, don't issue any warnings.
445  *
446  * %__GFP_REPEAT - If allocation fails initially, try once more before failing.
447  *
448  * There are other flags available as well, but these are not intended
449  * for general use, and so are not documented here. For a full list of
450  * potential flags, always refer to linux/gfp.h.
451  */
452 static __always_inline void *kmalloc(size_t size, gfp_t flags)
453 {
454         if (__builtin_constant_p(size)) {
455                 if (size > KMALLOC_MAX_CACHE_SIZE)
456                         return kmalloc_large(size, flags);
457 #ifndef CONFIG_SLOB
458                 if (!(flags & GFP_DMA)) {
459                         int index = kmalloc_index(size);
460 
461                         if (!index)
462                                 return ZERO_SIZE_PTR;
463 
464                         return kmem_cache_alloc_trace(kmalloc_caches[index],
465                                         flags, size);
466                 }
467 #endif
468         }
469         return __kmalloc(size, flags);
470 }
471 
472 /*
473  * Determine size used for the nth kmalloc cache.
474  * return size or 0 if a kmalloc cache for that
475  * size does not exist
476  */
477 static __always_inline int kmalloc_size(int n)
478 {
479 #ifndef CONFIG_SLOB
480         if (n > 2)
481                 return 1 << n;
482 
483         if (n == 1 && KMALLOC_MIN_SIZE <= 32)
484                 return 96;
485 
486         if (n == 2 && KMALLOC_MIN_SIZE <= 64)
487                 return 192;
488 #endif
489         return 0;
490 }
491 
492 static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
493 {
494 #ifndef CONFIG_SLOB
495         if (__builtin_constant_p(size) &&
496                 size <= KMALLOC_MAX_CACHE_SIZE && !(flags & GFP_DMA)) {
497                 int i = kmalloc_index(size);
498 
499                 if (!i)
500                         return ZERO_SIZE_PTR;
501 
502                 return kmem_cache_alloc_node_trace(kmalloc_caches[i],
503                                                 flags, node, size);
504         }
505 #endif
506         return __kmalloc_node(size, flags, node);
507 }
508 
509 /*
510  * Setting ARCH_SLAB_MINALIGN in arch headers allows a different alignment.
511  * Intended for arches that get misalignment faults even for 64 bit integer
512  * aligned buffers.
513  */
514 #ifndef ARCH_SLAB_MINALIGN
515 #define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
516 #endif
517 /*
518  * This is the main placeholder for memcg-related information in kmem caches.
519  * struct kmem_cache will hold a pointer to it, so the memory cost while
520  * disabled is 1 pointer. The runtime cost while enabled, gets bigger than it
521  * would otherwise be if that would be bundled in kmem_cache: we'll need an
522  * extra pointer chase. But the trade off clearly lays in favor of not
523  * penalizing non-users.
524  *
525  * Both the root cache and the child caches will have it. For the root cache,
526  * this will hold a dynamically allocated array large enough to hold
527  * information about the currently limited memcgs in the system. To allow the
528  * array to be accessed without taking any locks, on relocation we free the old
529  * version only after a grace period.
530  *
531  * Child caches will hold extra metadata needed for its operation. Fields are:
532  *
533  * @memcg: pointer to the memcg this cache belongs to
534  * @list: list_head for the list of all caches in this memcg
535  * @root_cache: pointer to the global, root cache, this cache was derived from
536  * @dead: set to true after the memcg dies; the cache may still be around.
537  * @nr_pages: number of pages that belongs to this cache.
538  * @destroy: worker to be called whenever we are ready, or believe we may be
539  *           ready, to destroy this cache.
540  */
541 struct memcg_cache_params {
542         bool is_root_cache;
543         union {
544                 struct {
545                         struct rcu_head rcu_head;
546                         struct kmem_cache *memcg_caches[0];
547                 };
548                 struct {
549                         struct mem_cgroup *memcg;
550                         struct list_head list;
551                         struct kmem_cache *root_cache;
552                         bool dead;
553                         atomic_t nr_pages;
554                         struct work_struct destroy;
555                 };
556         };
557 };
558 
559 int memcg_update_all_caches(int num_memcgs);
560 
561 struct seq_file;
562 int cache_show(struct kmem_cache *s, struct seq_file *m);
563 void print_slabinfo_header(struct seq_file *m);
564 
565 /**
566  * kmalloc_array - allocate memory for an array.
567  * @n: number of elements.
568  * @size: element size.
569  * @flags: the type of memory to allocate (see kmalloc).
570  */
571 static inline void *kmalloc_array(size_t n, size_t size, gfp_t flags)
572 {
573         if (size != 0 && n > SIZE_MAX / size)
574                 return NULL;
575         return __kmalloc(n * size, flags);
576 }
577 
578 /**
579  * kcalloc - allocate memory for an array. The memory is set to zero.
580  * @n: number of elements.
581  * @size: element size.
582  * @flags: the type of memory to allocate (see kmalloc).
583  */
584 static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
585 {
586         return kmalloc_array(n, size, flags | __GFP_ZERO);
587 }
588 
589 /*
590  * kmalloc_track_caller is a special version of kmalloc that records the
591  * calling function of the routine calling it for slab leak tracking instead
592  * of just the calling function (confusing, eh?).
593  * It's useful when the call to kmalloc comes from a widely-used standard
594  * allocator where we care about the real place the memory allocation
595  * request comes from.
596  */
597 #if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB) || \
598         (defined(CONFIG_SLAB) && defined(CONFIG_TRACING)) || \
599         (defined(CONFIG_SLOB) && defined(CONFIG_TRACING))
600 extern void *__kmalloc_track_caller(size_t, gfp_t, unsigned long);
601 #define kmalloc_track_caller(size, flags) \
602         __kmalloc_track_caller(size, flags, _RET_IP_)
603 #else
604 #define kmalloc_track_caller(size, flags) \
605         __kmalloc(size, flags)
606 #endif /* DEBUG_SLAB */
607 
608 #ifdef CONFIG_NUMA
609 /*
610  * kmalloc_node_track_caller is a special version of kmalloc_node that
611  * records the calling function of the routine calling it for slab leak
612  * tracking instead of just the calling function (confusing, eh?).
613  * It's useful when the call to kmalloc_node comes from a widely-used
614  * standard allocator where we care about the real place the memory
615  * allocation request comes from.
616  */
617 #if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_SLUB) || \
618         (defined(CONFIG_SLAB) && defined(CONFIG_TRACING)) || \
619         (defined(CONFIG_SLOB) && defined(CONFIG_TRACING))
620 extern void *__kmalloc_node_track_caller(size_t, gfp_t, int, unsigned long);
621 #define kmalloc_node_track_caller(size, flags, node) \
622         __kmalloc_node_track_caller(size, flags, node, \
623                         _RET_IP_)
624 #else
625 #define kmalloc_node_track_caller(size, flags, node) \
626         __kmalloc_node(size, flags, node)
627 #endif
628 
629 #else /* CONFIG_NUMA */
630 
631 #define kmalloc_node_track_caller(size, flags, node) \
632         kmalloc_track_caller(size, flags)
633 
634 #endif /* CONFIG_NUMA */
635 
636 /*
637  * Shortcuts
638  */
639 static inline void *kmem_cache_zalloc(struct kmem_cache *k, gfp_t flags)
640 {
641         return kmem_cache_alloc(k, flags | __GFP_ZERO);
642 }
643 
644 /**
645  * kzalloc - allocate memory. The memory is set to zero.
646  * @size: how many bytes of memory are required.
647  * @flags: the type of memory to allocate (see kmalloc).
648  */
649 static inline void *kzalloc(size_t size, gfp_t flags)
650 {
651         return kmalloc(size, flags | __GFP_ZERO);
652 }
653 
654 /**
655  * kzalloc_node - allocate zeroed memory from a particular memory node.
656  * @size: how many bytes of memory are required.
657  * @flags: the type of memory to allocate (see kmalloc).
658  * @node: memory node from which to allocate
659  */
660 static inline void *kzalloc_node(size_t size, gfp_t flags, int node)
661 {
662         return kmalloc_node(size, flags | __GFP_ZERO, node);
663 }
664 
665 /*
666  * Determine the size of a slab object
667  */
668 static inline unsigned int kmem_cache_size(struct kmem_cache *s)
669 {
670         return s->object_size;
671 }
672 
673 void __init kmem_cache_init_late(void);
674 
675 #endif  /* _LINUX_SLAB_H */
676 

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