Moved, renamed, and deleted files

The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.

1 files changed, 4682 insertions, 0 deletions

diff --git a/mm/slab.c b/mm/slab.c
new file mode 100644
index 00000000..e901a36e
--- /dev/null
+++ b/mm/slab.c
@@ -0,0 +1,4682 @@
+/*
+ * linux/mm/slab.c
+ * Written by Mark Hemment, 1996/97.
+ * (markhe@nextd.demon.co.uk)
+ *
+ * kmem_cache_destroy() + some cleanup - 1999 Andrea Arcangeli
+ *
+ * Major cleanup, different bufctl logic, per-cpu arrays
+ *	(c) 2000 Manfred Spraul
+ *
+ * Cleanup, make the head arrays unconditional, preparation for NUMA
+ * 	(c) 2002 Manfred Spraul
+ *
+ * An implementation of the Slab Allocator as described in outline in;
+ *	UNIX Internals: The New Frontiers by Uresh Vahalia
+ *	Pub: Prentice Hall	ISBN 0-13-101908-2
+ * or with a little more detail in;
+ *	The Slab Allocator: An Object-Caching Kernel Memory Allocator
+ *	Jeff Bonwick (Sun Microsystems).
+ *	Presented at: USENIX Summer 1994 Technical Conference
+ *
+ * The memory is organized in caches, one cache for each object type.
+ * (e.g. inode_cache, dentry_cache, buffer_head, vm_area_struct)
+ * Each cache consists out of many slabs (they are small (usually one
+ * page long) and always contiguous), and each slab contains multiple
+ * initialized objects.
+ *
+ * This means, that your constructor is used only for newly allocated
+ * slabs and you must pass objects with the same initializations to
+ * kmem_cache_free.
+ *
+ * Each cache can only support one memory type (GFP_DMA, GFP_HIGHMEM,
+ * normal). If you need a special memory type, then must create a new
+ * cache for that memory type.
+ *
+ * In order to reduce fragmentation, the slabs are sorted in 3 groups:
+ *   full slabs with 0 free objects
+ *   partial slabs
+ *   empty slabs with no allocated objects
+ *
+ * If partial slabs exist, then new allocations come from these slabs,
+ * otherwise from empty slabs or new slabs are allocated.
+ *
+ * kmem_cache_destroy() CAN CRASH if you try to allocate from the cache
+ * during kmem_cache_destroy(). The caller must prevent concurrent allocs.
+ *
+ * Each cache has a short per-cpu head array, most allocs
+ * and frees go into that array, and if that array overflows, then 1/2
+ * of the entries in the array are given back into the global cache.
+ * The head array is strictly LIFO and should improve the cache hit rates.
+ * On SMP, it additionally reduces the spinlock operations.
+ *
+ * The c_cpuarray may not be read with enabled local interrupts -
+ * it's changed with a smp_call_function().
+ *
+ * SMP synchronization:
+ *  constructors and destructors are called without any locking.
+ *  Several members in struct kmem_cache and struct slab never change, they
+ *	are accessed without any locking.
+ *  The per-cpu arrays are never accessed from the wrong cpu, no locking,
+ *  	and local interrupts are disabled so slab code is preempt-safe.
+ *  The non-constant members are protected with a per-cache irq spinlock.
+ *
+ * Many thanks to Mark Hemment, who wrote another per-cpu slab patch
+ * in 2000 - many ideas in the current implementation are derived from
+ * his patch.
+ *
+ * Further notes from the original documentation:
+ *
+ * 11 April '97.  Started multi-threading - markhe
+ *	The global cache-chain is protected by the mutex 'cache_chain_mutex'.
+ *	The sem is only needed when accessing/extending the cache-chain, which
+ *	can never happen inside an interrupt (kmem_cache_create(),
+ *	kmem_cache_shrink() and kmem_cache_reap()).
+ *
+ *	At present, each engine can be growing a cache.  This should be blocked.
+ *
+ * 15 March 2005. NUMA slab allocator.
+ *	Shai Fultheim <shai@scalex86.org>.
+ *	Shobhit Dayal <shobhit@calsoftinc.com>
+ *	Alok N Kataria <alokk@calsoftinc.com>
+ *	Christoph Lameter <christoph@lameter.com>
+ *
+ *	Modified the slab allocator to be node aware on NUMA systems.
+ *	Each node has its own list of partial, free and full slabs.
+ *	All object allocations for a node occur from node specific slab lists.
+ */
+
+#include	<linux/slab.h>
+#include	<linux/mm.h>
+#include	<linux/poison.h>
+#include	<linux/swap.h>
+#include	<linux/cache.h>
+#include	<linux/interrupt.h>
+#include	<linux/init.h>
+#include	<linux/compiler.h>
+#include	<linux/cpuset.h>
+#include	<linux/proc_fs.h>
+#include	<linux/seq_file.h>
+#include	<linux/notifier.h>
+#include	<linux/kallsyms.h>
+#include	<linux/cpu.h>
+#include	<linux/sysctl.h>
+#include	<linux/module.h>
+#include	<linux/rcupdate.h>
+#include	<linux/string.h>
+#include	<linux/uaccess.h>
+#include	<linux/nodemask.h>
+#include	<linux/kmemleak.h>
+#include	<linux/mempolicy.h>
+#include	<linux/mutex.h>
+#include	<linux/fault-inject.h>
+#include	<linux/rtmutex.h>
+#include	<linux/reciprocal_div.h>
+#include	<linux/debugobjects.h>
+#include	<linux/kmemcheck.h>
+#include	<linux/memory.h>
+#include	<linux/prefetch.h>
+
+#include	<asm/cacheflush.h>
+#include	<asm/tlbflush.h>
+#include	<asm/page.h>
+
+#include <trace/events/kmem.h>
+
+/*
+ * DEBUG	- 1 for kmem_cache_create() to honour; SLAB_RED_ZONE & SLAB_POISON.
+ *		  0 for faster, smaller code (especially in the critical paths).
+ *
+ * STATS	- 1 to collect stats for /proc/slabinfo.
+ *		  0 for faster, smaller code (especially in the critical paths).
+ *
+ * FORCED_DEBUG	- 1 enables SLAB_RED_ZONE and SLAB_POISON (if possible)
+ */
+
+#ifdef CONFIG_DEBUG_SLAB
+#define	DEBUG		1
+#define	STATS		1
+#define	FORCED_DEBUG	1
+#else
+#define	DEBUG		0
+#define	STATS		0
+#define	FORCED_DEBUG	0
+#endif
+
+/* Shouldn't this be in a header file somewhere? */
+#define	BYTES_PER_WORD		sizeof(void *)
+#define	REDZONE_ALIGN		max(BYTES_PER_WORD, __alignof__(unsigned long long))
+
+#ifndef ARCH_KMALLOC_FLAGS
+#define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN
+#endif
+
+/* Legal flag mask for kmem_cache_create(). */
+#if DEBUG
+# define CREATE_MASK	(SLAB_RED_ZONE | \
+			 SLAB_POISON | SLAB_HWCACHE_ALIGN | \
+			 SLAB_CACHE_DMA | \
+			 SLAB_STORE_USER | \
+			 SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \
+			 SLAB_DESTROY_BY_RCU | SLAB_MEM_SPREAD | \
+			 SLAB_DEBUG_OBJECTS | SLAB_NOLEAKTRACE | SLAB_NOTRACK)
+#else
+# define CREATE_MASK	(SLAB_HWCACHE_ALIGN | \
+			 SLAB_CACHE_DMA | \
+			 SLAB_RECLAIM_ACCOUNT | SLAB_PANIC | \
+			 SLAB_DESTROY_BY_RCU | SLAB_MEM_SPREAD | \
+			 SLAB_DEBUG_OBJECTS | SLAB_NOLEAKTRACE | SLAB_NOTRACK)
+#endif
+
+/*
+ * kmem_bufctl_t:
+ *
+ * Bufctl's are used for linking objs within a slab
+ * linked offsets.
+ *
+ * This implementation relies on "struct page" for locating the cache &
+ * slab an object belongs to.
+ * This allows the bufctl structure to be small (one int), but limits
+ * the number of objects a slab (not a cache) can contain when off-slab
+ * bufctls are used. The limit is the size of the largest general cache
+ * that does not use off-slab slabs.
+ * For 32bit archs with 4 kB pages, is this 56.
+ * This is not serious, as it is only for large objects, when it is unwise
+ * to have too many per slab.
+ * Note: This limit can be raised by introducing a general cache whose size
+ * is less than 512 (PAGE_SIZE<<3), but greater than 256.
+ */
+
+typedef unsigned int kmem_bufctl_t;
+#define BUFCTL_END	(((kmem_bufctl_t)(~0U))-0)
+#define BUFCTL_FREE	(((kmem_bufctl_t)(~0U))-1)
+#define	BUFCTL_ACTIVE	(((kmem_bufctl_t)(~0U))-2)
+#define	SLAB_LIMIT	(((kmem_bufctl_t)(~0U))-3)
+
+/*
+ * struct slab_rcu
+ *
+ * slab_destroy on a SLAB_DESTROY_BY_RCU cache uses this structure to
+ * arrange for kmem_freepages to be called via RCU.  This is useful if
+ * we need to approach a kernel structure obliquely, from its address
+ * obtained without the usual locking.  We can lock the structure to
+ * stabilize it and check it's still at the given address, only if we
+ * can be sure that the memory has not been meanwhile reused for some
+ * other kind of object (which our subsystem's lock might corrupt).
+ *
+ * rcu_read_lock before reading the address, then rcu_read_unlock after
+ * taking the spinlock within the structure expected at that address.
+ */
+struct slab_rcu {
+	struct rcu_head head;
+	struct kmem_cache *cachep;
+	void *addr;
+};
+
+/*
+ * struct slab
+ *
+ * Manages the objs in a slab. Placed either at the beginning of mem allocated
+ * for a slab, or allocated from an general cache.
+ * Slabs are chained into three list: fully used, partial, fully free slabs.
+ */
+struct slab {
+	union {
+		struct {
+			struct list_head list;
+			unsigned long colouroff;
+			void *s_mem;		/* including colour offset */
+			unsigned int inuse;	/* num of objs active in slab */
+			kmem_bufctl_t free;
+			unsigned short nodeid;
+		};
+		struct slab_rcu __slab_cover_slab_rcu;
+	};
+};
+
+/*
+ * struct array_cache
+ *
+ * Purpose:
+ * - LIFO ordering, to hand out cache-warm objects from _alloc
+ * - reduce the number of linked list operations
+ * - reduce spinlock operations
+ *
+ * The limit is stored in the per-cpu structure to reduce the data cache
+ * footprint.
+ *
+ */
+struct array_cache {
+	unsigned int avail;
+	unsigned int limit;
+	unsigned int batchcount;
+	unsigned int touched;
+	spinlock_t lock;
+	void *entry[];	/*
+			 * Must have this definition in here for the proper
+			 * alignment of array_cache. Also simplifies accessing
+			 * the entries.
+			 */
+};
+
+/*
+ * bootstrap: The caches do not work without cpuarrays anymore, but the
+ * cpuarrays are allocated from the generic caches...
+ */
+#define BOOT_CPUCACHE_ENTRIES	1
+struct arraycache_init {
+	struct array_cache cache;
+	void *entries[BOOT_CPUCACHE_ENTRIES];
+};
+
+/*
+ * The slab lists for all objects.
+ */
+struct kmem_list3 {
+	struct list_head slabs_partial;	/* partial list first, better asm code */
+	struct list_head slabs_full;
+	struct list_head slabs_free;
+	unsigned long free_objects;
+	unsigned int free_limit;
+	unsigned int colour_next;	/* Per-node cache coloring */
+	spinlock_t list_lock;
+	struct array_cache *shared;	/* shared per node */
+	struct array_cache **alien;	/* on other nodes */
+	unsigned long next_reap;	/* updated without locking */
+	int free_touched;		/* updated without locking */
+};
+
+/*
+ * Need this for bootstrapping a per node allocator.
+ */
+#define NUM_INIT_LISTS (3 * MAX_NUMNODES)
+static struct kmem_list3 __initdata initkmem_list3[NUM_INIT_LISTS];
+#define	CACHE_CACHE 0
+#define	SIZE_AC MAX_NUMNODES
+#define	SIZE_L3 (2 * MAX_NUMNODES)
+
+static int drain_freelist(struct kmem_cache *cache,
+			struct kmem_list3 *l3, int tofree);
+static void free_block(struct kmem_cache *cachep, void **objpp, int len,
+			int node);
+static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp);
+static void cache_reap(struct work_struct *unused);
+
+/*
+ * This function must be completely optimized away if a constant is passed to
+ * it.  Mostly the same as what is in linux/slab.h except it returns an index.
+ */
+static __always_inline int index_of(const size_t size)
+{
+	extern void __bad_size(void);
+
+	if (__builtin_constant_p(size)) {
+		int i = 0;
+
+#define CACHE(x) \
+	if (size <=x) \
+		return i; \
+	else \
+		i++;
+#include <linux/kmalloc_sizes.h>
+#undef CACHE
+		__bad_size();
+	} else
+		__bad_size();
+	return 0;
+}
+
+static int slab_early_init = 1;
+
+#define INDEX_AC index_of(sizeof(struct arraycache_init))
+#define INDEX_L3 index_of(sizeof(struct kmem_list3))
+
+static void kmem_list3_init(struct kmem_list3 *parent)
+{
+	INIT_LIST_HEAD(&parent->slabs_full);
+	INIT_LIST_HEAD(&parent->slabs_partial);
+	INIT_LIST_HEAD(&parent->slabs_free);
+	parent->shared = NULL;
+	parent->alien = NULL;
+	parent->colour_next = 0;
+	spin_lock_init(&parent->list_lock);
+	parent->free_objects = 0;
+	parent->free_touched = 0;
+}
+
+#define MAKE_LIST(cachep, listp, slab, nodeid)				\
+	do {								\
+		INIT_LIST_HEAD(listp);					\
+		list_splice(&(cachep->nodelists[nodeid]->slab), listp);	\
+	} while (0)
+
+#define	MAKE_ALL_LISTS(cachep, ptr, nodeid)				\
+	do {								\
+	MAKE_LIST((cachep), (&(ptr)->slabs_full), slabs_full, nodeid);	\
+	MAKE_LIST((cachep), (&(ptr)->slabs_partial), slabs_partial, nodeid); \
+	MAKE_LIST((cachep), (&(ptr)->slabs_free), slabs_free, nodeid);	\
+	} while (0)
+
+#define CFLGS_OFF_SLAB		(0x80000000UL)
+#define	OFF_SLAB(x)	((x)->flags & CFLGS_OFF_SLAB)
+
+#define BATCHREFILL_LIMIT	16
+/*
+ * Optimization question: fewer reaps means less probability for unnessary
+ * cpucache drain/refill cycles.
+ *
+ * OTOH the cpuarrays can contain lots of objects,
+ * which could lock up otherwise freeable slabs.
+ */
+#define REAPTIMEOUT_CPUC	(2*HZ)
+#define REAPTIMEOUT_LIST3	(4*HZ)
+
+#if STATS
+#define	STATS_INC_ACTIVE(x)	((x)->num_active++)
+#define	STATS_DEC_ACTIVE(x)	((x)->num_active--)
+#define	STATS_INC_ALLOCED(x)	((x)->num_allocations++)
+#define	STATS_INC_GROWN(x)	((x)->grown++)
+#define	STATS_ADD_REAPED(x,y)	((x)->reaped += (y))
+#define	STATS_SET_HIGH(x)						\
+	do {								\
+		if ((x)->num_active > (x)->high_mark)			\
+			(x)->high_mark = (x)->num_active;		\
+	} while (0)
+#define	STATS_INC_ERR(x)	((x)->errors++)
+#define	STATS_INC_NODEALLOCS(x)	((x)->node_allocs++)
+#define	STATS_INC_NODEFREES(x)	((x)->node_frees++)
+#define STATS_INC_ACOVERFLOW(x)   ((x)->node_overflow++)
+#define	STATS_SET_FREEABLE(x, i)					\
+	do {								\
+		if ((x)->max_freeable < i)				\
+			(x)->max_freeable = i;				\
+	} while (0)
+#define STATS_INC_ALLOCHIT(x)	atomic_inc(&(x)->allochit)
+#define STATS_INC_ALLOCMISS(x)	atomic_inc(&(x)->allocmiss)
+#define STATS_INC_FREEHIT(x)	atomic_inc(&(x)->freehit)
+#define STATS_INC_FREEMISS(x)	atomic_inc(&(x)->freemiss)
+#else
+#define	STATS_INC_ACTIVE(x)	do { } while (0)
+#define	STATS_DEC_ACTIVE(x)	do { } while (0)
+#define	STATS_INC_ALLOCED(x)	do { } while (0)
+#define	STATS_INC_GROWN(x)	do { } while (0)
+#define	STATS_ADD_REAPED(x,y)	do { (void)(y); } while (0)
+#define	STATS_SET_HIGH(x)	do { } while (0)
+#define	STATS_INC_ERR(x)	do { } while (0)
+#define	STATS_INC_NODEALLOCS(x)	do { } while (0)
+#define	STATS_INC_NODEFREES(x)	do { } while (0)
+#define STATS_INC_ACOVERFLOW(x)   do { } while (0)
+#define	STATS_SET_FREEABLE(x, i) do { } while (0)
+#define STATS_INC_ALLOCHIT(x)	do { } while (0)
+#define STATS_INC_ALLOCMISS(x)	do { } while (0)
+#define STATS_INC_FREEHIT(x)	do { } while (0)
+#define STATS_INC_FREEMISS(x)	do { } while (0)
+#endif
+
+#if DEBUG
+
+/*
+ * memory layout of objects:
+ * 0		: objp
+ * 0 .. cachep->obj_offset - BYTES_PER_WORD - 1: padding. This ensures that
+ * 		the end of an object is aligned with the end of the real
+ * 		allocation. Catches writes behind the end of the allocation.
+ * cachep->obj_offset - BYTES_PER_WORD .. cachep->obj_offset - 1:
+ * 		redzone word.
+ * cachep->obj_offset: The real object.
+ * cachep->buffer_size - 2* BYTES_PER_WORD: redzone word [BYTES_PER_WORD long]
+ * cachep->buffer_size - 1* BYTES_PER_WORD: last caller address
+ *					[BYTES_PER_WORD long]
+ */
+static int obj_offset(struct kmem_cache *cachep)
+{
+	return cachep->obj_offset;
+}
+
+static int obj_size(struct kmem_cache *cachep)
+{
+	return cachep->obj_size;
+}
+
+static unsigned long long *dbg_redzone1(struct kmem_cache *cachep, void *objp)
+{
+	BUG_ON(!(cachep->flags & SLAB_RED_ZONE));
+	return (unsigned long long*) (objp + obj_offset(cachep) -
+				      sizeof(unsigned long long));
+}
+
+static unsigned long long *dbg_redzone2(struct kmem_cache *cachep, void *objp)
+{
+	BUG_ON(!(cachep->flags & SLAB_RED_ZONE));
+	if (cachep->flags & SLAB_STORE_USER)
+		return (unsigned long long *)(objp + cachep->buffer_size -
+					      sizeof(unsigned long long) -
+					      REDZONE_ALIGN);
+	return (unsigned long long *) (objp + cachep->buffer_size -
+				       sizeof(unsigned long long));
+}
+
+static void **dbg_userword(struct kmem_cache *cachep, void *objp)
+{
+	BUG_ON(!(cachep->flags & SLAB_STORE_USER));
+	return (void **)(objp + cachep->buffer_size - BYTES_PER_WORD);
+}
+
+#else
+
+#define obj_offset(x)			0
+#define obj_size(cachep)		(cachep->buffer_size)
+#define dbg_redzone1(cachep, objp)	({BUG(); (unsigned long long *)NULL;})
+#define dbg_redzone2(cachep, objp)	({BUG(); (unsigned long long *)NULL;})
+#define dbg_userword(cachep, objp)	({BUG(); (void **)NULL;})
+
+#endif
+
+#ifdef CONFIG_TRACING
+size_t slab_buffer_size(struct kmem_cache *cachep)
+{
+	return cachep->buffer_size;
+}
+EXPORT_SYMBOL(slab_buffer_size);
+#endif
+
+/*
+ * Do not go above this order unless 0 objects fit into the slab or
+ * overridden on the command line.
+ */
+#define	SLAB_MAX_ORDER_HI	1
+#define	SLAB_MAX_ORDER_LO	0
+static int slab_max_order = SLAB_MAX_ORDER_LO;
+static bool slab_max_order_set __initdata;
+
+/*
+ * Functions for storing/retrieving the cachep and or slab from the page
+ * allocator.  These are used to find the slab an obj belongs to.  With kfree(),
+ * these are used to find the cache which an obj belongs to.
+ */
+static inline void page_set_cache(struct page *page, struct kmem_cache *cache)
+{
+	page->lru.next = (struct list_head *)cache;
+}
+
+static inline struct kmem_cache *page_get_cache(struct page *page)
+{
+	page = compound_head(page);
+	BUG_ON(!PageSlab(page));
+	return (struct kmem_cache *)page->lru.next;
+}
+
+static inline void page_set_slab(struct page *page, struct slab *slab)
+{
+	page->lru.prev = (struct list_head *)slab;
+}
+
+static inline struct slab *page_get_slab(struct page *page)
+{
+	BUG_ON(!PageSlab(page));
+	return (struct slab *)page->lru.prev;
+}
+
+static inline struct kmem_cache *virt_to_cache(const void *obj)
+{
+	struct page *page = virt_to_head_page(obj);
+	return page_get_cache(page);
+}
+
+static inline struct slab *virt_to_slab(const void *obj)
+{
+	struct page *page = virt_to_head_page(obj);
+	return page_get_slab(page);
+}
+
+static inline void *index_to_obj(struct kmem_cache *cache, struct slab *slab,
+				 unsigned int idx)
+{
+	return slab->s_mem + cache->buffer_size * idx;
+}
+
+/*
+ * We want to avoid an expensive divide : (offset / cache->buffer_size)
+ *   Using the fact that buffer_size is a constant for a particular cache,
+ *   we can replace (offset / cache->buffer_size) by
+ *   reciprocal_divide(offset, cache->reciprocal_buffer_size)
+ */
+static inline unsigned int obj_to_index(const struct kmem_cache *cache,
+					const struct slab *slab, void *obj)
+{
+	u32 offset = (obj - slab->s_mem);
+	return reciprocal_divide(offset, cache->reciprocal_buffer_size);
+}
+
+/*
+ * These are the default caches for kmalloc. Custom caches can have other sizes.
+ */
+struct cache_sizes malloc_sizes[] = {
+#define CACHE(x) { .cs_size = (x) },
+#include <linux/kmalloc_sizes.h>
+	CACHE(ULONG_MAX)
+#undef CACHE
+};
+EXPORT_SYMBOL(malloc_sizes);
+
+/* Must match cache_sizes above. Out of line to keep cache footprint low. */
+struct cache_names {
+	char *name;
+	char *name_dma;
+};
+
+static struct cache_names __initdata cache_names[] = {
+#define CACHE(x) { .name = "size-" #x, .name_dma = "size-" #x "(DMA)" },
+#include <linux/kmalloc_sizes.h>
+	{NULL,}
+#undef CACHE
+};
+
+static struct arraycache_init initarray_cache __initdata =
+    { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} };
+static struct arraycache_init initarray_generic =
+    { {0, BOOT_CPUCACHE_ENTRIES, 1, 0} };
+
+/* internal cache of cache description objs */
+static struct kmem_list3 *cache_cache_nodelists[MAX_NUMNODES];
+static struct kmem_cache cache_cache = {
+	.nodelists = cache_cache_nodelists,
+	.batchcount = 1,
+	.limit = BOOT_CPUCACHE_ENTRIES,
+	.shared = 1,
+	.buffer_size = sizeof(struct kmem_cache),
+	.name = "kmem_cache",
+};
+
+#define BAD_ALIEN_MAGIC 0x01020304ul
+
+/*
+ * chicken and egg problem: delay the per-cpu array allocation
+ * until the general caches are up.
+ */
+static enum {
+	NONE,
+	PARTIAL_AC,
+	PARTIAL_L3,
+	EARLY,
+	LATE,
+	FULL
+} g_cpucache_up;
+
+/*
+ * used by boot code to determine if it can use slab based allocator
+ */
+int slab_is_available(void)
+{
+	return g_cpucache_up >= EARLY;
+}
+
+#ifdef CONFIG_LOCKDEP
+
+/*
+ * Slab sometimes uses the kmalloc slabs to store the slab headers
+ * for other slabs "off slab".
+ * The locking for this is tricky in that it nests within the locks
+ * of all other slabs in a few places; to deal with this special
+ * locking we put on-slab caches into a separate lock-class.
+ *
+ * We set lock class for alien array caches which are up during init.
+ * The lock annotation will be lost if all cpus of a node goes down and
+ * then comes back up during hotplug
+ */
+static struct lock_class_key on_slab_l3_key;
+static struct lock_class_key on_slab_alc_key;
+
+static struct lock_class_key debugobj_l3_key;
+static struct lock_class_key debugobj_alc_key;
+
+static void slab_set_lock_classes(struct kmem_cache *cachep,
+		struct lock_class_key *l3_key, struct lock_class_key *alc_key,
+		int q)
+{
+	struct array_cache **alc;
+	struct kmem_list3 *l3;
+	int r;
+
+	l3 = cachep->nodelists[q];
+	if (!l3)
+		return;
+
+	lockdep_set_class(&l3->list_lock, l3_key);
+	alc = l3->alien;
+	/*
+	 * FIXME: This check for BAD_ALIEN_MAGIC
+	 * should go away when common slab code is taught to
+	 * work even without alien caches.
+	 * Currently, non NUMA code returns BAD_ALIEN_MAGIC
+	 * for alloc_alien_cache,
+	 */
+	if (!alc || (unsigned long)alc == BAD_ALIEN_MAGIC)
+		return;
+	for_each_node(r) {
+		if (alc[r])
+			lockdep_set_class(&alc[r]->lock, alc_key);
+	}
+}
+
+static void slab_set_debugobj_lock_classes_node(struct kmem_cache *cachep, int node)
+{
+	slab_set_lock_classes(cachep, &debugobj_l3_key, &debugobj_alc_key, node);
+}
+
+static void slab_set_debugobj_lock_classes(struct kmem_cache *cachep)
+{
+	int node;
+
+	for_each_online_node(node)
+		slab_set_debugobj_lock_classes_node(cachep, node);
+}
+
+static void init_node_lock_keys(int q)
+{
+	struct cache_sizes *s = malloc_sizes;
+
+	if (g_cpucache_up < LATE)
+		return;
+
+	for (s = malloc_sizes; s->cs_size != ULONG_MAX; s++) {
+		struct kmem_list3 *l3;
+
+		l3 = s->cs_cachep->nodelists[q];
+		if (!l3 || OFF_SLAB(s->cs_cachep))
+			continue;
+
+		slab_set_lock_classes(s->cs_cachep, &on_slab_l3_key,
+				&on_slab_alc_key, q);
+	}
+}
+
+static inline void init_lock_keys(void)
+{
+	int node;
+
+	for_each_node(node)
+		init_node_lock_keys(node);
+}
+#else
+static void init_node_lock_keys(int q)
+{
+}
+
+static inline void init_lock_keys(void)
+{
+}
+
+static void slab_set_debugobj_lock_classes_node(struct kmem_cache *cachep, int node)
+{
+}
+
+static void slab_set_debugobj_lock_classes(struct kmem_cache *cachep)
+{
+}
+#endif
+
+/*
+ * Guard access to the cache-chain.
+ */
+static DEFINE_MUTEX(cache_chain_mutex);
+static struct list_head cache_chain;
+
+static DEFINE_PER_CPU(struct delayed_work, slab_reap_work);
+
+static inline struct array_cache *cpu_cache_get(struct kmem_cache *cachep)
+{
+	return cachep->array[smp_processor_id()];
+}
+
+static inline struct kmem_cache *__find_general_cachep(size_t size,
+							gfp_t gfpflags)
+{
+	struct cache_sizes *csizep = malloc_sizes;
+
+#if DEBUG
+	/* This happens if someone tries to call
+	 * kmem_cache_create(), or __kmalloc(), before
+	 * the generic caches are initialized.
+	 */
+	BUG_ON(malloc_sizes[INDEX_AC].cs_cachep == NULL);
+#endif
+	if (!size)
+		return ZERO_SIZE_PTR;
+
+	while (size > csizep->cs_size)
+		csizep++;
+
+	/*
+	 * Really subtle: The last entry with cs->cs_size==ULONG_MAX
+	 * has cs_{dma,}cachep==NULL. Thus no special case
+	 * for large kmalloc calls required.
+	 */
+#ifdef CONFIG_ZONE_DMA
+	if (unlikely(gfpflags & GFP_DMA))
+		return csizep->cs_dmacachep;
+#endif
+	return csizep->cs_cachep;
+}
+
+static struct kmem_cache *kmem_find_general_cachep(size_t size, gfp_t gfpflags)
+{
+	return __find_general_cachep(size, gfpflags);
+}
+
+static size_t slab_mgmt_size(size_t nr_objs, size_t align)
+{
+	return ALIGN(sizeof(struct slab)+nr_objs*sizeof(kmem_bufctl_t), align);
+}
+
+/*
+ * Calculate the number of objects and left-over bytes for a given buffer size.
+ */
+static void cache_estimate(unsigned long gfporder, size_t buffer_size,
+			   size_t align, int flags, size_t *left_over,
+			   unsigned int *num)
+{
+	int nr_objs;
+	size_t mgmt_size;
+	size_t slab_size = PAGE_SIZE << gfporder;
+
+	/*
+	 * The slab management structure can be either off the slab or
+	 * on it. For the latter case, the memory allocated for a
+	 * slab is used for:
+	 *
+	 * - The struct slab
+	 * - One kmem_bufctl_t for each object
+	 * - Padding to respect alignment of @align
+	 * - @buffer_size bytes for each object
+	 *
+	 * If the slab management structure is off the slab, then the
+	 * alignment will already be calculated into the size. Because
+	 * the slabs are all pages aligned, the objects will be at the
+	 * correct alignment when allocated.
+	 */
+	if (flags & CFLGS_OFF_SLAB) {
+		mgmt_size = 0;
+		nr_objs = slab_size / buffer_size;
+
+		if (nr_objs > SLAB_LIMIT)
+			nr_objs = SLAB_LIMIT;
+	} else {
+		/*
+		 * Ignore padding for the initial guess. The padding
+		 * is at most @align-1 bytes, and @buffer_size is at
+		 * least @align. In the worst case, this result will
+		 * be one greater than the number of objects that fit
+		 * into the memory allocation when taking the padding
+		 * into account.
+		 */
+		nr_objs = (slab_size - sizeof(struct slab)) /
+			  (buffer_size + sizeof(kmem_bufctl_t));
+
+		/*
+		 * This calculated number will be either the right
+		 * amount, or one greater than what we want.
+		 */
+		if (slab_mgmt_size(nr_objs, align) + nr_objs*buffer_size
+		       > slab_size)
+			nr_objs--;
+
+		if (nr_objs > SLAB_LIMIT)
+			nr_objs = SLAB_LIMIT;
+
+		mgmt_size = slab_mgmt_size(nr_objs, align);
+	}
+	*num = nr_objs;
+	*left_over = slab_size - nr_objs*buffer_size - mgmt_size;
+}
+
+#define slab_error(cachep, msg) __slab_error(__func__, cachep, msg)
+
+static void __slab_error(const char *function, struct kmem_cache *cachep,
+			char *msg)
+{
+	printk(KERN_ERR "slab error in %s(): cache `%s': %s\n",
+	       function, cachep->name, msg);
+	dump_stack();
+}
+
+/*
+ * By default on NUMA we use alien caches to stage the freeing of
+ * objects allocated from other nodes. This causes massive memory
+ * inefficiencies when using fake NUMA setup to split memory into a
+ * large number of small nodes, so it can be disabled on the command
+ * line
+  */
+
+static int use_alien_caches __read_mostly = 1;
+static int __init noaliencache_setup(char *s)
+{
+	use_alien_caches = 0;
+	return 1;
+}
+__setup("noaliencache", noaliencache_setup);
+
+static int __init slab_max_order_setup(char *str)
+{
+	get_option(&str, &slab_max_order);
+	slab_max_order = slab_max_order < 0 ? 0 :
+				min(slab_max_order, MAX_ORDER - 1);
+	slab_max_order_set = true;
+
+	return 1;
+}
+__setup("slab_max_order=", slab_max_order_setup);
+
+#ifdef CONFIG_NUMA
+/*
+ * Special reaping functions for NUMA systems called from cache_reap().
+ * These take care of doing round robin flushing of alien caches (containing
+ * objects freed on different nodes from which they were allocated) and the
+ * flushing of remote pcps by calling drain_node_pages.
+ */
+static DEFINE_PER_CPU(unsigned long, slab_reap_node);
+
+static void init_reap_node(int cpu)
+{
+	int node;
+
+	node = next_node(cpu_to_mem(cpu), node_online_map);
+	if (node == MAX_NUMNODES)
+		node = first_node(node_online_map);
+
+	per_cpu(slab_reap_node, cpu) = node;
+}
+
+static void next_reap_node(void)
+{
+	int node = __this_cpu_read(slab_reap_node);
+
+	node = next_node(node, node_online_map);
+	if (unlikely(node >= MAX_NUMNODES))
+		node = first_node(node_online_map);
+	__this_cpu_write(slab_reap_node, node);
+}
+
+#else
+#define init_reap_node(cpu) do { } while (0)
+#define next_reap_node(void) do { } while (0)
+#endif
+
+/*
+ * Initiate the reap timer running on the target CPU.  We run at around 1 to 2Hz
+ * via the workqueue/eventd.
+ * Add the CPU number into the expiration time to minimize the possibility of
+ * the CPUs getting into lockstep and contending for the global cache chain
+ * lock.
+ */
+static void __cpuinit start_cpu_timer(int cpu)
+{
+	struct delayed_work *reap_work = &per_cpu(slab_reap_work, cpu);
+
+	/*
+	 * When this gets called from do_initcalls via cpucache_init(),
+	 * init_workqueues() has already run, so keventd will be setup
+	 * at that time.
+	 */
+	if (keventd_up() && reap_work->work.func == NULL) {
+		init_reap_node(cpu);
+		INIT_DELAYED_WORK_DEFERRABLE(reap_work, cache_reap);
+		schedule_delayed_work_on(cpu, reap_work,
+					__round_jiffies_relative(HZ, cpu));
+	}
+}
+
+static struct array_cache *alloc_arraycache(int node, int entries,
+					    int batchcount, gfp_t gfp)
+{
+	int memsize = sizeof(void *) * entries + sizeof(struct array_cache);
+	struct array_cache *nc = NULL;
+
+	nc = kmalloc_node(memsize, gfp, node);
+	/*
+	 * The array_cache structures contain pointers to free object.
+	 * However, when such objects are allocated or transferred to another
+	 * cache the pointers are not cleared and they could be counted as
+	 * valid references during a kmemleak scan. Therefore, kmemleak must
+	 * not scan such objects.
+	 */
+	kmemleak_no_scan(nc);
+	if (nc) {
+		nc->avail = 0;
+		nc->limit = entries;
+		nc->batchcount = batchcount;
+		nc->touched = 0;
+		spin_lock_init(&nc->lock);
+	}
+	return nc;
+}
+
+/*
+ * Transfer objects in one arraycache to another.
+ * Locking must be handled by the caller.
+ *
+ * Return the number of entries transferred.
+ */
+static int transfer_objects(struct array_cache *to,
+		struct array_cache *from, unsigned int max)
+{
+	/* Figure out how many entries to transfer */
+	int nr = min3(from->avail, max, to->limit - to->avail);
+
+	if (!nr)
+		return 0;
+
+	memcpy(to->entry + to->avail, from->entry + from->avail -nr,
+			sizeof(void *) *nr);
+
+	from->avail -= nr;
+	to->avail += nr;
+	return nr;
+}
+
+#ifndef CONFIG_NUMA
+
+#define drain_alien_cache(cachep, alien) do { } while (0)
+#define reap_alien(cachep, l3) do { } while (0)
+
+static inline struct array_cache **alloc_alien_cache(int node, int limit, gfp_t gfp)
+{
+	return (struct array_cache **)BAD_ALIEN_MAGIC;
+}
+
+static inline void free_alien_cache(struct array_cache **ac_ptr)
+{
+}
+
+static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)
+{
+	return 0;
+}
+
+static inline void *alternate_node_alloc(struct kmem_cache *cachep,
+		gfp_t flags)
+{
+	return NULL;
+}
+
+static inline void *____cache_alloc_node(struct kmem_cache *cachep,
+		 gfp_t flags, int nodeid)
+{
+	return NULL;
+}
+
+#else	/* CONFIG_NUMA */
+
+static void *____cache_alloc_node(struct kmem_cache *, gfp_t, int);
+static void *alternate_node_alloc(struct kmem_cache *, gfp_t);
+
+static struct array_cache **alloc_alien_cache(int node, int limit, gfp_t gfp)
+{
+	struct array_cache **ac_ptr;
+	int memsize = sizeof(void *) * nr_node_ids;
+	int i;
+
+	if (limit > 1)
+		limit = 12;
+	ac_ptr = kzalloc_node(memsize, gfp, node);
+	if (ac_ptr) {
+		for_each_node(i) {
+			if (i == node || !node_online(i))
+				continue;
+			ac_ptr[i] = alloc_arraycache(node, limit, 0xbaadf00d, gfp);
+			if (!ac_ptr[i]) {
+				for (i--; i >= 0; i--)
+					kfree(ac_ptr[i]);
+				kfree(ac_ptr);
+				return NULL;
+			}
+		}
+	}
+	return ac_ptr;
+}
+
+static void free_alien_cache(struct array_cache **ac_ptr)
+{
+	int i;
+
+	if (!ac_ptr)
+		return;
+	for_each_node(i)
+	    kfree(ac_ptr[i]);
+	kfree(ac_ptr);
+}
+
+static void __drain_alien_cache(struct kmem_cache *cachep,
+				struct array_cache *ac, int node)
+{
+	struct kmem_list3 *rl3 = cachep->nodelists[node];
+
+	if (ac->avail) {
+		spin_lock(&rl3->list_lock);
+		/*
+		 * Stuff objects into the remote nodes shared array first.
+		 * That way we could avoid the overhead of putting the objects
+		 * into the free lists and getting them back later.
+		 */
+		if (rl3->shared)
+			transfer_objects(rl3->shared, ac, ac->limit);
+
+		free_block(cachep, ac->entry, ac->avail, node);
+		ac->avail = 0;
+		spin_unlock(&rl3->list_lock);
+	}
+}
+
+/*
+ * Called from cache_reap() to regularly drain alien caches round robin.
+ */
+static void reap_alien(struct kmem_cache *cachep, struct kmem_list3 *l3)
+{
+	int node = __this_cpu_read(slab_reap_node);
+
+	if (l3->alien) {
+		struct array_cache *ac = l3->alien[node];
+
+		if (ac && ac->avail && spin_trylock_irq(&ac->lock)) {
+			__drain_alien_cache(cachep, ac, node);
+			spin_unlock_irq(&ac->lock);
+		}
+	}
+}
+
+static void drain_alien_cache(struct kmem_cache *cachep,
+				struct array_cache **alien)
+{
+	int i = 0;
+	struct array_cache *ac;
+	unsigned long flags;
+
+	for_each_online_node(i) {
+		ac = alien[i];
+		if (ac) {
+			spin_lock_irqsave(&ac->lock, flags);
+			__drain_alien_cache(cachep, ac, i);
+			spin_unlock_irqrestore(&ac->lock, flags);
+		}
+	}
+}
+
+static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)
+{
+	struct slab *slabp = virt_to_slab(objp);
+	int nodeid = slabp->nodeid;
+	struct kmem_list3 *l3;
+	struct array_cache *alien = NULL;
+	int node;
+
+	node = numa_mem_id();
+
+	/*
+	 * Make sure we are not freeing a object from another node to the array
+	 * cache on this cpu.
+	 */
+	if (likely(slabp->nodeid == node))
+		return 0;
+
+	l3 = cachep->nodelists[node];
+	STATS_INC_NODEFREES(cachep);
+	if (l3->alien && l3->alien[nodeid]) {
+		alien = l3->alien[nodeid];
+		spin_lock(&alien->lock);
+		if (unlikely(alien->avail == alien->limit)) {
+			STATS_INC_ACOVERFLOW(cachep);
+			__drain_alien_cache(cachep, alien, nodeid);
+		}
+		alien->entry[alien->avail++] = objp;
+		spin_unlock(&alien->lock);
+	} else {
+		spin_lock(&(cachep->nodelists[nodeid])->list_lock);
+		free_block(cachep, &objp, 1, nodeid);
+		spin_unlock(&(cachep->nodelists[nodeid])->list_lock);
+	}
+	return 1;
+}
+#endif
+
+/*
+ * Allocates and initializes nodelists for a node on each slab cache, used for
+ * either memory or cpu hotplug.  If memory is being hot-added, the kmem_list3
+ * will be allocated off-node since memory is not yet online for the new node.
+ * When hotplugging memory or a cpu, existing nodelists are not replaced if
+ * already in use.
+ *
+ * Must hold cache_chain_mutex.
+ */
+static int init_cache_nodelists_node(int node)
+{
+	struct kmem_cache *cachep;
+	struct kmem_list3 *l3;
+	const int memsize = sizeof(struct kmem_list3);
+
+	list_for_each_entry(cachep, &cache_chain, next) {
+		/*
+		 * Set up the size64 kmemlist for cpu before we can
+		 * begin anything. Make sure some other cpu on this
+		 * node has not already allocated this
+		 */
+		if (!cachep->nodelists[node]) {
+			l3 = kmalloc_node(memsize, GFP_KERNEL, node);
+			if (!l3)
+				return -ENOMEM;
+			kmem_list3_init(l3);
+			l3->next_reap = jiffies + REAPTIMEOUT_LIST3 +
+			    ((unsigned long)cachep) % REAPTIMEOUT_LIST3;
+
+			/*
+			 * The l3s don't come and go as CPUs come and
+			 * go.  cache_chain_mutex is sufficient
+			 * protection here.
+			 */
+			cachep->nodelists[node] = l3;
+		}
+
+		spin_lock_irq(&cachep->nodelists[node]->list_lock);
+		cachep->nodelists[node]->free_limit =
+			(1 + nr_cpus_node(node)) *
+			cachep->batchcount + cachep->num;
+		spin_unlock_irq(&cachep->nodelists[node]->list_lock);
+	}
+	return 0;
+}
+
+static void __cpuinit cpuup_canceled(long cpu)
+{
+	struct kmem_cache *cachep;
+	struct kmem_list3 *l3 = NULL;
+	int node = cpu_to_mem(cpu);
+	const struct cpumask *mask = cpumask_of_node(node);
+
+	list_for_each_entry(cachep, &cache_chain, next) {
+		struct array_cache *nc;
+		struct array_cache *shared;
+		struct array_cache **alien;
+
+		/* cpu is dead; no one can alloc from it. */
+		nc = cachep->array[cpu];
+		cachep->array[cpu] = NULL;
+		l3 = cachep->nodelists[node];
+
+		if (!l3)
+			goto free_array_cache;
+
+		spin_lock_irq(&l3->list_lock);
+
+		/* Free limit for this kmem_list3 */
+		l3->free_limit -= cachep->batchcount;
+		if (nc)
+			free_block(cachep, nc->entry, nc->avail, node);
+
+		if (!cpumask_empty(mask)) {
+			spin_unlock_irq(&l3->list_lock);
+			goto free_array_cache;
+		}
+
+		shared = l3->shared;
+		if (shared) {
+			free_block(cachep, shared->entry,
+				   shared->avail, node);
+			l3->shared = NULL;
+		}
+
+		alien = l3->alien;
+		l3->alien = NULL;
+
+		spin_unlock_irq(&l3->list_lock);
+
+		kfree(shared);
+		if (alien) {
+			drain_alien_cache(cachep, alien);
+			free_alien_cache(alien);
+		}
+free_array_cache:
+		kfree(nc);
+	}
+	/*
+	 * In the previous loop, all the objects were freed to
+	 * the respective cache's slabs,  now we can go ahead and
+	 * shrink each nodelist to its limit.
+	 */
+	list_for_each_entry(cachep, &cache_chain, next) {
+		l3 = cachep->nodelists[node];
+		if (!l3)
+			continue;
+		drain_freelist(cachep, l3, l3->free_objects);
+	}
+}
+
+static int __cpuinit cpuup_prepare(long cpu)
+{
+	struct kmem_cache *cachep;
+	struct kmem_list3 *l3 = NULL;
+	int node = cpu_to_mem(cpu);
+	int err;
+
+	/*
+	 * We need to do this right in the beginning since
+	 * alloc_arraycache's are going to use this list.
+	 * kmalloc_node allows us to add the slab to the right
+	 * kmem_list3 and not this cpu's kmem_list3
+	 */
+	err = init_cache_nodelists_node(node);
+	if (err < 0)
+		goto bad;
+
+	/*
+	 * Now we can go ahead with allocating the shared arrays and
+	 * array caches
+	 */
+	list_for_each_entry(cachep, &cache_chain, next) {
+		struct array_cache *nc;
+		struct array_cache *shared = NULL;
+		struct array_cache **alien = NULL;
+
+		nc = alloc_arraycache(node, cachep->limit,
+					cachep->batchcount, GFP_KERNEL);
+		if (!nc)
+			goto bad;
+		if (cachep->shared) {
+			shared = alloc_arraycache(node,
+				cachep->shared * cachep->batchcount,
+				0xbaadf00d, GFP_KERNEL);
+			if (!shared) {
+				kfree(nc);
+				goto bad;
+			}
+		}
+		if (use_alien_caches) {
+			alien = alloc_alien_cache(node, cachep->limit, GFP_KERNEL);
+			if (!alien) {
+				kfree(shared);
+				kfree(nc);
+				goto bad;
+			}
+		}
+		cachep->array[cpu] = nc;
+		l3 = cachep->nodelists[node];
+		BUG_ON(!l3);
+
+		spin_lock_irq(&l3->list_lock);
+		if (!l3->shared) {
+			/*
+			 * We are serialised from CPU_DEAD or
+			 * CPU_UP_CANCELLED by the cpucontrol lock
+			 */
+			l3->shared = shared;
+			shared = NULL;
+		}
+#ifdef CONFIG_NUMA
+		if (!l3->alien) {
+			l3->alien = alien;
+			alien = NULL;
+		}
+#endif
+		spin_unlock_irq(&l3->list_lock);
+		kfree(shared);
+		free_alien_cache(alien);
+		if (cachep->flags & SLAB_DEBUG_OBJECTS)
+			slab_set_debugobj_lock_classes_node(cachep, node);
+	}
+	init_node_lock_keys(node);
+
+	return 0;
+bad:
+	cpuup_canceled(cpu);
+	return -ENOMEM;
+}
+
+static int __cpuinit cpuup_callback(struct notifier_block *nfb,
+				    unsigned long action, void *hcpu)
+{
+	long cpu = (long)hcpu;
+	int err = 0;
+
+	switch (action) {
+	case CPU_UP_PREPARE:
+	case CPU_UP_PREPARE_FROZEN:
+		mutex_lock(&cache_chain_mutex);
+		err = cpuup_prepare(cpu);
+		mutex_unlock(&cache_chain_mutex);
+		break;
+	case CPU_ONLINE:
+	case CPU_ONLINE_FROZEN:
+		start_cpu_timer(cpu);
+		break;
+#ifdef CONFIG_HOTPLUG_CPU
+  	case CPU_DOWN_PREPARE:
+  	case CPU_DOWN_PREPARE_FROZEN:
+		/*
+		 * Shutdown cache reaper. Note that the cache_chain_mutex is
+		 * held so that if cache_reap() is invoked it cannot do
+		 * anything expensive but will only modify reap_work
+		 * and reschedule the timer.
+		*/
+		cancel_delayed_work_sync(&per_cpu(slab_reap_work, cpu));
+		/* Now the cache_reaper is guaranteed to be not running. */
+		per_cpu(slab_reap_work, cpu).work.func = NULL;
+  		break;
+  	case CPU_DOWN_FAILED:
+  	case CPU_DOWN_FAILED_FROZEN:
+		start_cpu_timer(cpu);
+  		break;
+	case CPU_DEAD:
+	case CPU_DEAD_FROZEN:
+		/*
+		 * Even if all the cpus of a node are down, we don't free the
+		 * kmem_list3 of any cache. This to avoid a race between
+		 * cpu_down, and a kmalloc allocation from another cpu for
+		 * memory from the node of the cpu going down.  The list3
+		 * structure is usually allocated from kmem_cache_create() and
+		 * gets destroyed at kmem_cache_destroy().
+		 */
+		/* fall through */
+#endif
+	case CPU_UP_CANCELED:
+	case CPU_UP_CANCELED_FROZEN:
+		mutex_lock(&cache_chain_mutex);
+		cpuup_canceled(cpu);
+		mutex_unlock(&cache_chain_mutex);
+		break;
+	}
+	return notifier_from_errno(err);
+}
+
+static struct notifier_block __cpuinitdata cpucache_notifier = {
+	&cpuup_callback, NULL, 0
+};
+
+#if defined(CONFIG_NUMA) && defined(CONFIG_MEMORY_HOTPLUG)
+/*
+ * Drains freelist for a node on each slab cache, used for memory hot-remove.
+ * Returns -EBUSY if all objects cannot be drained so that the node is not
+ * removed.
+ *
+ * Must hold cache_chain_mutex.
+ */
+static int __meminit drain_cache_nodelists_node(int node)
+{
+	struct kmem_cache *cachep;
+	int ret = 0;
+
+	list_for_each_entry(cachep, &cache_chain, next) {
+		struct kmem_list3 *l3;
+
+		l3 = cachep->nodelists[node];
+		if (!l3)
+			continue;
+
+		drain_freelist(cachep, l3, l3->free_objects);
+
+		if (!list_empty(&l3->slabs_full) ||
+		    !list_empty(&l3->slabs_partial)) {
+			ret = -EBUSY;
+			break;
+		}
+	}
+	return ret;
+}
+
+static int __meminit slab_memory_callback(struct notifier_block *self,
+					unsigned long action, void *arg)
+{
+	struct memory_notify *mnb = arg;
+	int ret = 0;
+	int nid;
+
+	nid = mnb->status_change_nid;
+	if (nid < 0)
+		goto out;
+
+	switch (action) {
+	case MEM_GOING_ONLINE:
+		mutex_lock(&cache_chain_mutex);
+		ret = init_cache_nodelists_node(nid);
+		mutex_unlock(&cache_chain_mutex);
+		break;
+	case MEM_GOING_OFFLINE:
+		mutex_lock(&cache_chain_mutex);
+		ret = drain_cache_nodelists_node(nid);
+		mutex_unlock(&cache_chain_mutex);
+		break;
+	case MEM_ONLINE:
+	case MEM_OFFLINE:
+	case MEM_CANCEL_ONLINE:
+	case MEM_CANCEL_OFFLINE:
+		break;
+	}
+out:
+	return notifier_from_errno(ret);
+}
+#endif /* CONFIG_NUMA && CONFIG_MEMORY_HOTPLUG */
+
+/*
+ * swap the static kmem_list3 with kmalloced memory
+ */
+static void __init init_list(struct kmem_cache *cachep, struct kmem_list3 *list,
+				int nodeid)
+{
+	struct kmem_list3 *ptr;
+
+	ptr = kmalloc_node(sizeof(struct kmem_list3), GFP_NOWAIT, nodeid);
+	BUG_ON(!ptr);
+
+	memcpy(ptr, list, sizeof(struct kmem_list3));
+	/*
+	 * Do not assume that spinlocks can be initialized via memcpy:
+	 */
+	spin_lock_init(&ptr->list_lock);
+
+	MAKE_ALL_LISTS(cachep, ptr, nodeid);
+	cachep->nodelists[nodeid] = ptr;
+}
+
+/*
+ * For setting up all the kmem_list3s for cache whose buffer_size is same as
+ * size of kmem_list3.
+ */
+static void __init set_up_list3s(struct kmem_cache *cachep, int index)
+{
+	int node;
+
+	for_each_online_node(node) {
+		cachep->nodelists[node] = &initkmem_list3[index + node];
+		cachep->nodelists[node]->next_reap = jiffies +
+		    REAPTIMEOUT_LIST3 +
+		    ((unsigned long)cachep) % REAPTIMEOUT_LIST3;
+	}
+}
+
+/*
+ * Initialisation.  Called after the page allocator have been initialised and
+ * before smp_init().
+ */
+void __init kmem_cache_init(void)
+{
+	size_t left_over;
+	struct cache_sizes *sizes;
+	struct cache_names *names;
+	int i;
+	int order;
+	int node;
+
+	if (num_possible_nodes() == 1)
+		use_alien_caches = 0;
+
+	for (i = 0; i < NUM_INIT_LISTS; i++) {
+		kmem_list3_init(&initkmem_list3[i]);
+		if (i < MAX_NUMNODES)
+			cache_cache.nodelists[i] = NULL;
+	}
+	set_up_list3s(&cache_cache, CACHE_CACHE);
+
+	/*
+	 * Fragmentation resistance on low memory - only use bigger
+	 * page orders on machines with more than 32MB of memory if
+	 * not overridden on the command line.
+	 */
+	if (!slab_max_order_set && totalram_pages > (32 << 20) >> PAGE_SHIFT)
+		slab_max_order = SLAB_MAX_ORDER_HI;
+
+	/* Bootstrap is tricky, because several objects are allocated
+	 * from caches that do not exist yet:
+	 * 1) initialize the cache_cache cache: it contains the struct
+	 *    kmem_cache structures of all caches, except cache_cache itself:
+	 *    cache_cache is statically allocated.
+	 *    Initially an __init data area is used for the head array and the
+	 *    kmem_list3 structures, it's replaced with a kmalloc allocated
+	 *    array at the end of the bootstrap.
+	 * 2) Create the first kmalloc cache.
+	 *    The struct kmem_cache for the new cache is allocated normally.
+	 *    An __init data area is used for the head array.
+	 * 3) Create the remaining kmalloc caches, with minimally sized
+	 *    head arrays.
+	 * 4) Replace the __init data head arrays for cache_cache and the first
+	 *    kmalloc cache with kmalloc allocated arrays.
+	 * 5) Replace the __init data for kmem_list3 for cache_cache and
+	 *    the other cache's with kmalloc allocated memory.
+	 * 6) Resize the head arrays of the kmalloc caches to their final sizes.
+	 */
+
+	node = numa_mem_id();
+
+	/* 1) create the cache_cache */
+	INIT_LIST_HEAD(&cache_chain);
+	list_add(&cache_cache.next, &cache_chain);
+	cache_cache.colour_off = cache_line_size();
+	cache_cache.array[smp_processor_id()] = &initarray_cache.cache;
+	cache_cache.nodelists[node] = &initkmem_list3[CACHE_CACHE + node];
+
+	/*
+	 * struct kmem_cache size depends on nr_node_ids & nr_cpu_ids
+	 */
+	cache_cache.buffer_size = offsetof(struct kmem_cache, array[nr_cpu_ids]) +
+				  nr_node_ids * sizeof(struct kmem_list3 *);
+#if DEBUG
+	cache_cache.obj_size = cache_cache.buffer_size;
+#endif
+	cache_cache.buffer_size = ALIGN(cache_cache.buffer_size,
+					cache_line_size());
+	cache_cache.reciprocal_buffer_size =
+		reciprocal_value(cache_cache.buffer_size);
+
+	for (order = 0; order < MAX_ORDER; order++) {
+		cache_estimate(order, cache_cache.buffer_size,
+			cache_line_size(), 0, &left_over, &cache_cache.num);
+		if (cache_cache.num)
+			break;
+	}
+	BUG_ON(!cache_cache.num);
+	cache_cache.gfporder = order;
+	cache_cache.colour = left_over / cache_cache.colour_off;
+	cache_cache.slab_size = ALIGN(cache_cache.num * sizeof(kmem_bufctl_t) +
+				      sizeof(struct slab), cache_line_size());
+
+	/* 2+3) create the kmalloc caches */
+	sizes = malloc_sizes;
+	names = cache_names;
+
+	/*
+	 * Initialize the caches that provide memory for the array cache and the
+	 * kmem_list3 structures first.  Without this, further allocations will
+	 * bug.
+	 */
+
+	sizes[INDEX_AC].cs_cachep = kmem_cache_create(names[INDEX_AC].name,
+					sizes[INDEX_AC].cs_size,
+					ARCH_KMALLOC_MINALIGN,
+					ARCH_KMALLOC_FLAGS|SLAB_PANIC,
+					NULL);
+
+	if (INDEX_AC != INDEX_L3) {
+		sizes[INDEX_L3].cs_cachep =
+			kmem_cache_create(names[INDEX_L3].name,
+				sizes[INDEX_L3].cs_size,
+				ARCH_KMALLOC_MINALIGN,
+				ARCH_KMALLOC_FLAGS|SLAB_PANIC,
+				NULL);
+	}
+
+	slab_early_init = 0;
+
+	while (sizes->cs_size != ULONG_MAX) {
+		/*
+		 * For performance, all the general caches are L1 aligned.
+		 * This should be particularly beneficial on SMP boxes, as it
+		 * eliminates "false sharing".
+		 * Note for systems short on memory removing the alignment will
+		 * allow tighter packing of the smaller caches.
+		 */
+		if (!sizes->cs_cachep) {
+			sizes->cs_cachep = kmem_cache_create(names->name,
+					sizes->cs_size,
+					ARCH_KMALLOC_MINALIGN,
+					ARCH_KMALLOC_FLAGS|SLAB_PANIC,
+					NULL);
+		}
+#ifdef CONFIG_ZONE_DMA
+		sizes->cs_dmacachep = kmem_cache_create(
+					names->name_dma,
+					sizes->cs_size,
+					ARCH_KMALLOC_MINALIGN,
+					ARCH_KMALLOC_FLAGS|SLAB_CACHE_DMA|
+						SLAB_PANIC,
+					NULL);
+#endif
+		sizes++;
+		names++;
+	}
+	/* 4) Replace the bootstrap head arrays */
+	{
+		struct array_cache *ptr;
+
+		ptr = kmalloc(sizeof(struct arraycache_init), GFP_NOWAIT);
+
+		BUG_ON(cpu_cache_get(&cache_cache) != &initarray_cache.cache);
+		memcpy(ptr, cpu_cache_get(&cache_cache),
+		       sizeof(struct arraycache_init));
+		/*
+		 * Do not assume that spinlocks can be initialized via memcpy:
+		 */
+		spin_lock_init(&ptr->lock);
+
+		cache_cache.array[smp_processor_id()] = ptr;
+
+		ptr = kmalloc(sizeof(struct arraycache_init), GFP_NOWAIT);
+
+		BUG_ON(cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep)
+		       != &initarray_generic.cache);
+		memcpy(ptr, cpu_cache_get(malloc_sizes[INDEX_AC].cs_cachep),
+		       sizeof(struct arraycache_init));
+		/*
+		 * Do not assume that spinlocks can be initialized via memcpy:
+		 */
+		spin_lock_init(&ptr->lock);
+
+		malloc_sizes[INDEX_AC].cs_cachep->array[smp_processor_id()] =
+		    ptr;
+	}
+	/* 5) Replace the bootstrap kmem_list3's */
+	{
+		int nid;
+
+		for_each_online_node(nid) {
+			init_list(&cache_cache, &initkmem_list3[CACHE_CACHE + nid], nid);
+
+			init_list(malloc_sizes[INDEX_AC].cs_cachep,
+				  &initkmem_list3[SIZE_AC + nid], nid);
+
+			if (INDEX_AC != INDEX_L3) {
+				init_list(malloc_sizes[INDEX_L3].cs_cachep,
+					  &initkmem_list3[SIZE_L3 + nid], nid);
+			}
+		}
+	}
+
+	g_cpucache_up = EARLY;
+}
+
+void __init kmem_cache_init_late(void)
+{
+	struct kmem_cache *cachep;
+
+	g_cpucache_up = LATE;
+
+	/* Annotate slab for lockdep -- annotate the malloc caches */
+	init_lock_keys();
+
+	/* 6) resize the head arrays to their final sizes */
+	mutex_lock(&cache_chain_mutex);
+	list_for_each_entry(cachep, &cache_chain, next)
+		if (enable_cpucache(cachep, GFP_NOWAIT))
+			BUG();
+	mutex_unlock(&cache_chain_mutex);
+
+	/* Done! */
+	g_cpucache_up = FULL;
+
+	/*
+	 * Register a cpu startup notifier callback that initializes
+	 * cpu_cache_get for all new cpus
+	 */
+	register_cpu_notifier(&cpucache_notifier);
+
+#ifdef CONFIG_NUMA
+	/*
+	 * Register a memory hotplug callback that initializes and frees
+	 * nodelists.
+	 */
+	hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI);
+#endif
+
+	/*
+	 * The reap timers are started later, with a module init call: That part
+	 * of the kernel is not yet operational.
+	 */
+}
+
+static int __init cpucache_init(void)
+{
+	int cpu;
+
+	/*
+	 * Register the timers that return unneeded pages to the page allocator
+	 */
+	for_each_online_cpu(cpu)
+		start_cpu_timer(cpu);
+	return 0;
+}
+__initcall(cpucache_init);
+
+static noinline void
+slab_out_of_memory(struct kmem_cache *cachep, gfp_t gfpflags, int nodeid)
+{
+	struct kmem_list3 *l3;
+	struct slab *slabp;
+	unsigned long flags;
+	int node;
+
+	printk(KERN_WARNING
+		"SLAB: Unable to allocate memory on node %d (gfp=0x%x)\n",
+		nodeid, gfpflags);
+	printk(KERN_WARNING "  cache: %s, object size: %d, order: %d\n",
+		cachep->name, cachep->buffer_size, cachep->gfporder);
+
+	for_each_online_node(node) {
+		unsigned long active_objs = 0, num_objs = 0, free_objects = 0;
+		unsigned long active_slabs = 0, num_slabs = 0;
+
+		l3 = cachep->nodelists[node];
+		if (!l3)
+			continue;
+
+		spin_lock_irqsave(&l3->list_lock, flags);
+		list_for_each_entry(slabp, &l3->slabs_full, list) {
+			active_objs += cachep->num;
+			active_slabs++;
+		}
+		list_for_each_entry(slabp, &l3->slabs_partial, list) {
+			active_objs += slabp->inuse;
+			active_slabs++;
+		}
+		list_for_each_entry(slabp, &l3->slabs_free, list)
+			num_slabs++;
+
+		free_objects += l3->free_objects;
+		spin_unlock_irqrestore(&l3->list_lock, flags);
+
+		num_slabs += active_slabs;
+		num_objs = num_slabs * cachep->num;
+		printk(KERN_WARNING
+			"  node %d: slabs: %ld/%ld, objs: %ld/%ld, free: %ld\n",
+			node, active_slabs, num_slabs, active_objs, num_objs,
+			free_objects);
+	}
+}
+
+/*
+ * Interface to system's page allocator. No need to hold the cache-lock.
+ *
+ * If we requested dmaable memory, we will get it. Even if we
+ * did not request dmaable memory, we might get it, but that
+ * would be relatively rare and ignorable.
+ */
+static void *kmem_getpages(struct kmem_cache *cachep, gfp_t flags, int nodeid)
+{
+	struct page *page;
+	int nr_pages;
+	int i;
+
+#ifndef CONFIG_MMU
+	/*
+	 * Nommu uses slab's for process anonymous memory allocations, and thus
+	 * requires __GFP_COMP to properly refcount higher order allocations
+	 */
+	flags |= __GFP_COMP;
+#endif
+
+	flags |= cachep->gfpflags;
+	if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
+		flags |= __GFP_RECLAIMABLE;
+
+	page = alloc_pages_exact_node(nodeid, flags | __GFP_NOTRACK, cachep->gfporder);
+	if (!page) {
+		if (!(flags & __GFP_NOWARN) && printk_ratelimit())
+			slab_out_of_memory(cachep, flags, nodeid);
+		return NULL;
+	}
+
+	nr_pages = (1 << cachep->gfporder);
+	if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
+		add_zone_page_state(page_zone(page),
+			NR_SLAB_RECLAIMABLE, nr_pages);
+	else
+		add_zone_page_state(page_zone(page),
+			NR_SLAB_UNRECLAIMABLE, nr_pages);
+	for (i = 0; i < nr_pages; i++)
+		__SetPageSlab(page + i);
+
+	if (kmemcheck_enabled && !(cachep->flags & SLAB_NOTRACK)) {
+		kmemcheck_alloc_shadow(page, cachep->gfporder, flags, nodeid);
+
+		if (cachep->ctor)
+			kmemcheck_mark_uninitialized_pages(page, nr_pages);
+		else
+			kmemcheck_mark_unallocated_pages(page, nr_pages);
+	}
+
+	return page_address(page);
+}
+
+/*
+ * Interface to system's page release.
+ */
+static void kmem_freepages(struct kmem_cache *cachep, void *addr)
+{
+	unsigned long i = (1 << cachep->gfporder);
+	struct page *page = virt_to_page(addr);
+	const unsigned long nr_freed = i;
+
+	kmemcheck_free_shadow(page, cachep->gfporder);
+
+	if (cachep->flags & SLAB_RECLAIM_ACCOUNT)
+		sub_zone_page_state(page_zone(page),
+				NR_SLAB_RECLAIMABLE, nr_freed);
+	else
+		sub_zone_page_state(page_zone(page),
+				NR_SLAB_UNRECLAIMABLE, nr_freed);
+	while (i--) {
+		BUG_ON(!PageSlab(page));
+		__ClearPageSlab(page);
+		page++;
+	}
+	if (current->reclaim_state)
+		current->reclaim_state->reclaimed_slab += nr_freed;
+	free_pages((unsigned long)addr, cachep->gfporder);
+}
+
+static void kmem_rcu_free(struct rcu_head *head)
+{
+	struct slab_rcu *slab_rcu = (struct slab_rcu *)head;
+	struct kmem_cache *cachep = slab_rcu->cachep;
+
+	kmem_freepages(cachep, slab_rcu->addr);
+	if (OFF_SLAB(cachep))
+		kmem_cache_free(cachep->slabp_cache, slab_rcu);
+}
+
+#if DEBUG
+
+#ifdef CONFIG_DEBUG_PAGEALLOC
+static void store_stackinfo(struct kmem_cache *cachep, unsigned long *addr,
+			    unsigned long caller)
+{
+	int size = obj_size(cachep);
+
+	addr = (unsigned long *)&((char *)addr)[obj_offset(cachep)];
+
+	if (size < 5 * sizeof(unsigned long))
+		return;
+
+	*addr++ = 0x12345678;
+	*addr++ = caller;
+	*addr++ = smp_processor_id();
+	size -= 3 * sizeof(unsigned long);
+	{
+		unsigned long *sptr = &caller;
+		unsigned long svalue;
+
+		while (!kstack_end(sptr)) {
+			svalue = *sptr++;
+			if (kernel_text_address(svalue)) {
+				*addr++ = svalue;
+				size -= sizeof(unsigned long);
+				if (size <= sizeof(unsigned long))
+					break;
+			}
+		}
+
+	}
+	*addr++ = 0x87654321;
+}
+#endif
+
+static void poison_obj(struct kmem_cache *cachep, void *addr, unsigned char val)
+{
+	int size = obj_size(cachep);
+	addr = &((char *)addr)[obj_offset(cachep)];
+
+	memset(addr, val, size);
+	*(unsigned char *)(addr + size - 1) = POISON_END;
+}
+
+static void dump_line(char *data, int offset, int limit)
+{
+	int i;
+	unsigned char error = 0;
+	int bad_count = 0;
+
+	printk(KERN_ERR "%03x: ", offset);
+	for (i = 0; i < limit; i++) {
+		if (data[offset + i] != POISON_FREE) {
+			error = data[offset + i];
+			bad_count++;
+		}
+	}
+	print_hex_dump(KERN_CONT, "", 0, 16, 1,
+			&data[offset], limit, 1);
+
+	if (bad_count == 1) {
+		error ^= POISON_FREE;
+		if (!(error & (error - 1))) {
+			printk(KERN_ERR "Single bit error detected. Probably "
+					"bad RAM.\n");
+#ifdef CONFIG_X86
+			printk(KERN_ERR "Run memtest86+ or a similar memory "
+					"test tool.\n");
+#else
+			printk(KERN_ERR "Run a memory test tool.\n");
+#endif
+		}
+	}
+}
+#endif
+
+#if DEBUG
+
+static void print_objinfo(struct kmem_cache *cachep, void *objp, int lines)
+{
+	int i, size;
+	char *realobj;
+
+	if (cachep->flags & SLAB_RED_ZONE) {
+		printk(KERN_ERR "Redzone: 0x%llx/0x%llx.\n",
+			*dbg_redzone1(cachep, objp),
+			*dbg_redzone2(cachep, objp));
+	}
+
+	if (cachep->flags & SLAB_STORE_USER) {
+		printk(KERN_ERR "Last user: [<%p>]",
+			*dbg_userword(cachep, objp));
+		print_symbol("(%s)",
+				(unsigned long)*dbg_userword(cachep, objp));
+		printk("\n");
+	}
+	realobj = (char *)objp + obj_offset(cachep);
+	size = obj_size(cachep);
+	for (i = 0; i < size && lines; i += 16, lines--) {
+		int limit;
+		limit = 16;
+		if (i + limit > size)
+			limit = size - i;
+		dump_line(realobj, i, limit);
+	}
+}
+
+static void check_poison_obj(struct kmem_cache *cachep, void *objp)
+{
+	char *realobj;
+	int size, i;
+	int lines = 0;
+
+	realobj = (char *)objp + obj_offset(cachep);
+	size = obj_size(cachep);
+
+	for (i = 0; i < size; i++) {
+		char exp = POISON_FREE;
+		if (i == size - 1)
+			exp = POISON_END;
+		if (realobj[i] != exp) {
+			int limit;
+			/* Mismatch ! */
+			/* Print header */
+			if (lines == 0) {
+				printk(KERN_ERR
+					"Slab corruption (%s): %s start=%p, len=%d\n",
+					print_tainted(), cachep->name, realobj, size);
+				print_objinfo(cachep, objp, 0);
+			}
+			/* Hexdump the affected line */
+			i = (i / 16) * 16;
+			limit = 16;
+			if (i + limit > size)
+				limit = size - i;
+			dump_line(realobj, i, limit);
+			i += 16;
+			lines++;
+			/* Limit to 5 lines */
+			if (lines > 5)
+				break;
+		}
+	}
+	if (lines != 0) {
+		/* Print some data about the neighboring objects, if they
+		 * exist:
+		 */
+		struct slab *slabp = virt_to_slab(objp);
+		unsigned int objnr;
+
+		objnr = obj_to_index(cachep, slabp, objp);
+		if (objnr) {
+			objp = index_to_obj(cachep, slabp, objnr - 1);
+			realobj = (char *)objp + obj_offset(cachep);
+			printk(KERN_ERR "Prev obj: start=%p, len=%d\n",
+			       realobj, size);
+			print_objinfo(cachep, objp, 2);
+		}
+		if (objnr + 1 < cachep->num) {
+			objp = index_to_obj(cachep, slabp, objnr + 1);
+			realobj = (char *)objp + obj_offset(cachep);
+			printk(KERN_ERR "Next obj: start=%p, len=%d\n",
+			       realobj, size);
+			print_objinfo(cachep, objp, 2);
+		}
+	}
+}
+#endif
+
+#if DEBUG
+static void slab_destroy_debugcheck(struct kmem_cache *cachep, struct slab *slabp)
+{
+	int i;
+	for (i = 0; i < cachep->num; i++) {
+		void *objp = index_to_obj(cachep, slabp, i);
+
+		if (cachep->flags & SLAB_POISON) {
+#ifdef CONFIG_DEBUG_PAGEALLOC
+			if (cachep->buffer_size % PAGE_SIZE == 0 &&
+					OFF_SLAB(cachep))
+				kernel_map_pages(virt_to_page(objp),
+					cachep->buffer_size / PAGE_SIZE, 1);
+			else
+				check_poison_obj(cachep, objp);
+#else
+			check_poison_obj(cachep, objp);
+#endif
+		}
+		if (cachep->flags & SLAB_RED_ZONE) {
+			if (*dbg_redzone1(cachep, objp) != RED_INACTIVE)
+				slab_error(cachep, "start of a freed object "
+					   "was overwritten");
+			if (*dbg_redzone2(cachep, objp) != RED_INACTIVE)
+				slab_error(cachep, "end of a freed object "
+					   "was overwritten");
+		}
+	}
+}
+#else
+static void slab_destroy_debugcheck(struct kmem_cache *cachep, struct slab *slabp)
+{
+}
+#endif
+
+/**
+ * slab_destroy - destroy and release all objects in a slab
+ * @cachep: cache pointer being destroyed
+ * @slabp: slab pointer being destroyed
+ *
+ * Destroy all the objs in a slab, and release the mem back to the system.
+ * Before calling the slab must have been unlinked from the cache.  The
+ * cache-lock is not held/needed.
+ */
+static void slab_destroy(struct kmem_cache *cachep, struct slab *slabp)
+{
+	void *addr = slabp->s_mem - slabp->colouroff;
+
+	slab_destroy_debugcheck(cachep, slabp);
+	if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU)) {
+		struct slab_rcu *slab_rcu;
+
+		slab_rcu = (struct slab_rcu *)slabp;
+		slab_rcu->cachep = cachep;
+		slab_rcu->addr = addr;
+		call_rcu(&slab_rcu->head, kmem_rcu_free);
+	} else {
+		kmem_freepages(cachep, addr);
+		if (OFF_SLAB(cachep))
+			kmem_cache_free(cachep->slabp_cache, slabp);
+	}
+}
+
+static void __kmem_cache_destroy(struct kmem_cache *cachep)
+{
+	int i;
+	struct kmem_list3 *l3;
+
+	for_each_online_cpu(i)
+	    kfree(cachep->array[i]);
+
+	/* NUMA: free the list3 structures */
+	for_each_online_node(i) {
+		l3 = cachep->nodelists[i];
+		if (l3) {
+			kfree(l3->shared);
+			free_alien_cache(l3->alien);
+			kfree(l3);
+		}
+	}
+	kmem_cache_free(&cache_cache, cachep);
+}
+
+
+/**
+ * calculate_slab_order - calculate size (page order) of slabs
+ * @cachep: pointer to the cache that is being created
+ * @size: size of objects to be created in this cache.
+ * @align: required alignment for the objects.
+ * @flags: slab allocation flags
+ *
+ * Also calculates the number of objects per slab.
+ *
+ * This could be made much more intelligent.  For now, try to avoid using
+ * high order pages for slabs.  When the gfp() functions are more friendly
+ * towards high-order requests, this should be changed.
+ */
+static size_t calculate_slab_order(struct kmem_cache *cachep,
+			size_t size, size_t align, unsigned long flags)
+{
+	unsigned long offslab_limit;
+	size_t left_over = 0;
+	int gfporder;
+
+	for (gfporder = 0; gfporder <= KMALLOC_MAX_ORDER; gfporder++) {
+		unsigned int num;
+		size_t remainder;
+
+		cache_estimate(gfporder, size, align, flags, &remainder, &num);
+		if (!num)
+			continue;
+
+		if (flags & CFLGS_OFF_SLAB) {
+			/*
+			 * Max number of objs-per-slab for caches which
+			 * use off-slab slabs. Needed to avoid a possible
+			 * looping condition in cache_grow().
+			 */
+			offslab_limit = size - sizeof(struct slab);
+			offslab_limit /= sizeof(kmem_bufctl_t);
+
+ 			if (num > offslab_limit)
+				break;
+		}
+
+		/* Found something acceptable - save it away */
+		cachep->num = num;
+		cachep->gfporder = gfporder;
+		left_over = remainder;
+
+		/*
+		 * A VFS-reclaimable slab tends to have most allocations
+		 * as GFP_NOFS and we really don't want to have to be allocating
+		 * higher-order pages when we are unable to shrink dcache.
+		 */
+		if (flags & SLAB_RECLAIM_ACCOUNT)
+			break;
+
+		/*
+		 * Large number of objects is good, but very large slabs are
+		 * currently bad for the gfp()s.
+		 */
+		if (gfporder >= slab_max_order)
+			break;
+
+		/*
+		 * Acceptable internal fragmentation?
+		 */
+		if (left_over * 8 <= (PAGE_SIZE << gfporder))
+			break;
+	}
+	return left_over;
+}
+
+static int __init_refok setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp)
+{
+	if (g_cpucache_up == FULL)
+		return enable_cpucache(cachep, gfp);
+
+	if (g_cpucache_up == NONE) {
+		/*
+		 * Note: the first kmem_cache_create must create the cache
+		 * that's used by kmalloc(24), otherwise the creation of
+		 * further caches will BUG().
+		 */
+		cachep->array[smp_processor_id()] = &initarray_generic.cache;
+
+		/*
+		 * If the cache that's used by kmalloc(sizeof(kmem_list3)) is
+		 * the first cache, then we need to set up all its list3s,
+		 * otherwise the creation of further caches will BUG().
+		 */
+		set_up_list3s(cachep, SIZE_AC);
+		if (INDEX_AC == INDEX_L3)
+			g_cpucache_up = PARTIAL_L3;
+		else
+			g_cpucache_up = PARTIAL_AC;
+	} else {
+		cachep->array[smp_processor_id()] =
+			kmalloc(sizeof(struct arraycache_init), gfp);
+
+		if (g_cpucache_up == PARTIAL_AC) {
+			set_up_list3s(cachep, SIZE_L3);
+			g_cpucache_up = PARTIAL_L3;
+		} else {
+			int node;
+			for_each_online_node(node) {
+				cachep->nodelists[node] =
+				    kmalloc_node(sizeof(struct kmem_list3),
+						gfp, node);
+				BUG_ON(!cachep->nodelists[node]);
+				kmem_list3_init(cachep->nodelists[node]);
+			}
+		}
+	}
+	cachep->nodelists[numa_mem_id()]->next_reap =
+			jiffies + REAPTIMEOUT_LIST3 +
+			((unsigned long)cachep) % REAPTIMEOUT_LIST3;
+
+	cpu_cache_get(cachep)->avail = 0;
+	cpu_cache_get(cachep)->limit = BOOT_CPUCACHE_ENTRIES;
+	cpu_cache_get(cachep)->batchcount = 1;
+	cpu_cache_get(cachep)->touched = 0;
+	cachep->batchcount = 1;
+	cachep->limit = BOOT_CPUCACHE_ENTRIES;
+	return 0;
+}
+
+/**
+ * kmem_cache_create - Create a cache.
+ * @name: A string which is used in /proc/slabinfo to identify this cache.
+ * @size: The size of objects to be created in this cache.
+ * @align: The required alignment for the objects.
+ * @flags: SLAB flags
+ * @ctor: A constructor for the objects.
+ *
+ * Returns a ptr to the cache on success, NULL on failure.
+ * Cannot be called within a int, but can be interrupted.
+ * The @ctor is run when new pages are allocated by the cache.
+ *
+ * @name must be valid until the cache is destroyed. This implies that
+ * the module calling this has to destroy the cache before getting unloaded.
+ *
+ * The flags are
+ *
+ * %SLAB_POISON - Poison the slab with a known test pattern (a5a5a5a5)
+ * to catch references to uninitialised memory.
+ *
+ * %SLAB_RED_ZONE - Insert `Red' zones around the allocated memory to check
+ * for buffer overruns.
+ *
+ * %SLAB_HWCACHE_ALIGN - Align the objects in this cache to a hardware
+ * cacheline.  This can be beneficial if you're counting cycles as closely
+ * as davem.
+ */
+struct kmem_cache *
+kmem_cache_create (const char *name, size_t size, size_t align,
+	unsigned long flags, void (*ctor)(void *))
+{
+	size_t left_over, slab_size, ralign;
+	struct kmem_cache *cachep = NULL, *pc;
+	gfp_t gfp;
+
+	/*
+	 * Sanity checks... these are all serious usage bugs.
+	 */
+	if (!name || in_interrupt() || (size < BYTES_PER_WORD) ||
+	    size > KMALLOC_MAX_SIZE) {
+		printk(KERN_ERR "%s: Early error in slab %s\n", __func__,
+				name);
+		BUG();
+	}
+
+	/*
+	 * We use cache_chain_mutex to ensure a consistent view of
+	 * cpu_online_mask as well.  Please see cpuup_callback
+	 */
+	if (slab_is_available()) {
+		get_online_cpus();
+		mutex_lock(&cache_chain_mutex);
+	}
+
+	list_for_each_entry(pc, &cache_chain, next) {
+		char tmp;
+		int res;
+
+		/*
+		 * This happens when the module gets unloaded and doesn't
+		 * destroy its slab cache and no-one else reuses the vmalloc
+		 * area of the module.  Print a warning.
+		 */
+		res = probe_kernel_address(pc->name, tmp);
+		if (res) {
+			printk(KERN_ERR
+			       "SLAB: cache with size %d has lost its name\n",
+			       pc->buffer_size);
+			continue;
+		}
+
+		if (!strcmp(pc->name, name)) {
+			printk(KERN_ERR
+			       "kmem_cache_create: duplicate cache %s\n", name);
+			dump_stack();
+			goto oops;
+		}
+	}
+
+#if DEBUG
+	WARN_ON(strchr(name, ' '));	/* It confuses parsers */
+#if FORCED_DEBUG
+	/*
+	 * Enable redzoning and last user accounting, except for caches with
+	 * large objects, if the increased size would increase the object size
+	 * above the next power of two: caches with object sizes just above a
+	 * power of two have a significant amount of internal fragmentation.
+	 */
+	if (size < 4096 || fls(size - 1) == fls(size-1 + REDZONE_ALIGN +
+						2 * sizeof(unsigned long long)))
+		flags |= SLAB_RED_ZONE | SLAB_STORE_USER;
+	if (!(flags & SLAB_DESTROY_BY_RCU))
+		flags |= SLAB_POISON;
+#endif
+	if (flags & SLAB_DESTROY_BY_RCU)
+		BUG_ON(flags & SLAB_POISON);
+#endif
+	/*
+	 * Always checks flags, a caller might be expecting debug support which
+	 * isn't available.
+	 */
+	BUG_ON(flags & ~CREATE_MASK);
+
+	/*
+	 * Check that size is in terms of words.  This is needed to avoid
+	 * unaligned accesses for some archs when redzoning is used, and makes
+	 * sure any on-slab bufctl's are also correctly aligned.
+	 */
+	if (size & (BYTES_PER_WORD - 1)) {
+		size += (BYTES_PER_WORD - 1);
+		size &= ~(BYTES_PER_WORD - 1);
+	}
+
+	/* calculate the final buffer alignment: */
+
+	/* 1) arch recommendation: can be overridden for debug */
+	if (flags & SLAB_HWCACHE_ALIGN) {
+		/*
+		 * Default alignment: as specified by the arch code.  Except if
+		 * an object is really small, then squeeze multiple objects into
+		 * one cacheline.
+		 */
+		ralign = cache_line_size();
+		while (size <= ralign / 2)
+			ralign /= 2;
+	} else {
+		ralign = BYTES_PER_WORD;
+	}
+
+	/*
+	 * Redzoning and user store require word alignment or possibly larger.
+	 * Note this will be overridden by architecture or caller mandated
+	 * alignment if either is greater than BYTES_PER_WORD.
+	 */
+	if (flags & SLAB_STORE_USER)
+		ralign = BYTES_PER_WORD;
+
+	if (flags & SLAB_RED_ZONE) {
+		ralign = REDZONE_ALIGN;
+		/* If redzoning, ensure that the second redzone is suitably
+		 * aligned, by adjusting the object size accordingly. */
+		size += REDZONE_ALIGN - 1;
+		size &= ~(REDZONE_ALIGN - 1);
+	}
+
+	/* 2) arch mandated alignment */
+	if (ralign < ARCH_SLAB_MINALIGN) {
+		ralign = ARCH_SLAB_MINALIGN;
+	}
+	/* 3) caller mandated alignment */
+	if (ralign < align) {
+		ralign = align;
+	}
+	/* disable debug if necessary */
+	if (ralign > __alignof__(unsigned long long))
+		flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
+	/*
+	 * 4) Store it.
+	 */
+	align = ralign;
+
+	if (slab_is_available())
+		gfp = GFP_KERNEL;
+	else
+		gfp = GFP_NOWAIT;
+
+	/* Get cache's description obj. */
+	cachep = kmem_cache_zalloc(&cache_cache, gfp);
+	if (!cachep)
+		goto oops;
+
+	cachep->nodelists = (struct kmem_list3 **)&cachep->array[nr_cpu_ids];
+#if DEBUG
+	cachep->obj_size = size;
+
+	/*
+	 * Both debugging options require word-alignment which is calculated
+	 * into align above.
+	 */
+	if (flags & SLAB_RED_ZONE) {
+		/* add space for red zone words */
+		cachep->obj_offset += sizeof(unsigned long long);
+		size += 2 * sizeof(unsigned long long);
+	}
+	if (flags & SLAB_STORE_USER) {
+		/* user store requires one word storage behind the end of
+		 * the real object. But if the second red zone needs to be
+		 * aligned to 64 bits, we must allow that much space.
+		 */
+		if (flags & SLAB_RED_ZONE)
+			size += REDZONE_ALIGN;
+		else
+			size += BYTES_PER_WORD;
+	}
+#if FORCED_DEBUG && defined(CONFIG_DEBUG_PAGEALLOC)
+	if (size >= malloc_sizes[INDEX_L3 + 1].cs_size
+	    && cachep->obj_size > cache_line_size() && ALIGN(size, align) < PAGE_SIZE) {
+		cachep->obj_offset += PAGE_SIZE - ALIGN(size, align);
+		size = PAGE_SIZE;
+	}
+#endif
+#endif
+
+	/*
+	 * Determine if the slab management is 'on' or 'off' slab.
+	 * (bootstrapping cannot cope with offslab caches so don't do
+	 * it too early on. Always use on-slab management when
+	 * SLAB_NOLEAKTRACE to avoid recursive calls into kmemleak)
+	 */
+	if ((size >= (PAGE_SIZE >> 3)) && !slab_early_init &&
+	    !(flags & SLAB_NOLEAKTRACE))
+		/*
+		 * Size is large, assume best to place the slab management obj
+		 * off-slab (should allow better packing of objs).
+		 */
+		flags |= CFLGS_OFF_SLAB;
+
+	size = ALIGN(size, align);
+
+	left_over = calculate_slab_order(cachep, size, align, flags);
+
+	if (!cachep->num) {
+		printk(KERN_ERR
+		       "kmem_cache_create: couldn't create cache %s.\n", name);
+		kmem_cache_free(&cache_cache, cachep);
+		cachep = NULL;
+		goto oops;
+	}
+	slab_size = ALIGN(cachep->num * sizeof(kmem_bufctl_t)
+			  + sizeof(struct slab), align);
+
+	/*
+	 * If the slab has been placed off-slab, and we have enough space then
+	 * move it on-slab. This is at the expense of any extra colouring.
+	 */
+	if (flags & CFLGS_OFF_SLAB && left_over >= slab_size) {
+		flags &= ~CFLGS_OFF_SLAB;
+		left_over -= slab_size;
+	}
+
+	if (flags & CFLGS_OFF_SLAB) {
+		/* really off slab. No need for manual alignment */
+		slab_size =
+		    cachep->num * sizeof(kmem_bufctl_t) + sizeof(struct slab);
+
+#ifdef CONFIG_PAGE_POISONING
+		/* If we're going to use the generic kernel_map_pages()
+		 * poisoning, then it's going to smash the contents of
+		 * the redzone and userword anyhow, so switch them off.
+		 */
+		if (size % PAGE_SIZE == 0 && flags & SLAB_POISON)
+			flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
+#endif
+	}
+
+	cachep->colour_off = cache_line_size();
+	/* Offset must be a multiple of the alignment. */
+	if (cachep->colour_off < align)
+		cachep->colour_off = align;
+	cachep->colour = left_over / cachep->colour_off;
+	cachep->slab_size = slab_size;
+	cachep->flags = flags;
+	cachep->gfpflags = 0;
+	if (CONFIG_ZONE_DMA_FLAG && (flags & SLAB_CACHE_DMA))
+		cachep->gfpflags |= GFP_DMA;
+	cachep->buffer_size = size;
+	cachep->reciprocal_buffer_size = reciprocal_value(size);
+
+	if (flags & CFLGS_OFF_SLAB) {
+		cachep->slabp_cache = kmem_find_general_cachep(slab_size, 0u);
+		/*
+		 * This is a possibility for one of the malloc_sizes caches.
+		 * But since we go off slab only for object size greater than
+		 * PAGE_SIZE/8, and malloc_sizes gets created in ascending order,
+		 * this should not happen at all.
+		 * But leave a BUG_ON for some lucky dude.
+		 */
+		BUG_ON(ZERO_OR_NULL_PTR(cachep->slabp_cache));
+	}
+	cachep->ctor = ctor;
+	cachep->name = name;
+
+	if (setup_cpu_cache(cachep, gfp)) {
+		__kmem_cache_destroy(cachep);
+		cachep = NULL;
+		goto oops;
+	}
+
+	if (flags & SLAB_DEBUG_OBJECTS) {
+		/*
+		 * Would deadlock through slab_destroy()->call_rcu()->
+		 * debug_object_activate()->kmem_cache_alloc().
+		 */
+		WARN_ON_ONCE(flags & SLAB_DESTROY_BY_RCU);
+
+		slab_set_debugobj_lock_classes(cachep);
+	}
+
+	/* cache setup completed, link it into the list */
+	list_add(&cachep->next, &cache_chain);
+oops:
+	if (!cachep && (flags & SLAB_PANIC))
+		panic("kmem_cache_create(): failed to create slab `%s'\n",
+		      name);
+	if (slab_is_available()) {
+		mutex_unlock(&cache_chain_mutex);
+		put_online_cpus();
+	}
+	return cachep;
+}
+EXPORT_SYMBOL(kmem_cache_create);
+
+#if DEBUG
+static void check_irq_off(void)
+{
+	BUG_ON(!irqs_disabled());
+}
+
+static void check_irq_on(void)
+{
+	BUG_ON(irqs_disabled());
+}
+
+static void check_spinlock_acquired(struct kmem_cache *cachep)
+{
+#ifdef CONFIG_SMP
+	check_irq_off();
+	assert_spin_locked(&cachep->nodelists[numa_mem_id()]->list_lock);
+#endif
+}
+
+static void check_spinlock_acquired_node(struct kmem_cache *cachep, int node)
+{
+#ifdef CONFIG_SMP
+	check_irq_off();
+	assert_spin_locked(&cachep->nodelists[node]->list_lock);
+#endif
+}
+
+#else
+#define check_irq_off()	do { } while(0)
+#define check_irq_on()	do { } while(0)
+#define check_spinlock_acquired(x) do { } while(0)
+#define check_spinlock_acquired_node(x, y) do { } while(0)
+#endif
+
+static void drain_array(struct kmem_cache *cachep, struct kmem_list3 *l3,
+			struct array_cache *ac,
+			int force, int node);
+
+static void do_drain(void *arg)
+{
+	struct kmem_cache *cachep = arg;
+	struct array_cache *ac;
+	int node = numa_mem_id();
+
+	check_irq_off();
+	ac = cpu_cache_get(cachep);
+	spin_lock(&cachep->nodelists[node]->list_lock);
+	free_block(cachep, ac->entry, ac->avail, node);
+	spin_unlock(&cachep->nodelists[node]->list_lock);
+	ac->avail = 0;
+}
+
+static void drain_cpu_caches(struct kmem_cache *cachep)
+{
+	struct kmem_list3 *l3;
+	int node;
+
+	on_each_cpu(do_drain, cachep, 1);
+	check_irq_on();
+	for_each_online_node(node) {
+		l3 = cachep->nodelists[node];
+		if (l3 && l3->alien)
+			drain_alien_cache(cachep, l3->alien);
+	}
+
+	for_each_online_node(node) {
+		l3 = cachep->nodelists[node];
+		if (l3)
+			drain_array(cachep, l3, l3->shared, 1, node);
+	}
+}
+
+/*
+ * Remove slabs from the list of free slabs.
+ * Specify the number of slabs to drain in tofree.
+ *
+ * Returns the actual number of slabs released.
+ */
+static int drain_freelist(struct kmem_cache *cache,
+			struct kmem_list3 *l3, int tofree)
+{
+	struct list_head *p;
+	int nr_freed;
+	struct slab *slabp;
+
+	nr_freed = 0;
+	while (nr_freed < tofree && !list_empty(&l3->slabs_free)) {
+
+		spin_lock_irq(&l3->list_lock);
+		p = l3->slabs_free.prev;
+		if (p == &l3->slabs_free) {
+			spin_unlock_irq(&l3->list_lock);
+			goto out;
+		}
+
+		slabp = list_entry(p, struct slab, list);
+#if DEBUG
+		BUG_ON(slabp->inuse);
+#endif
+		list_del(&slabp->list);
+		/*
+		 * Safe to drop the lock. The slab is no longer linked
+		 * to the cache.
+		 */
+		l3->free_objects -= cache->num;
+		spin_unlock_irq(&l3->list_lock);
+		slab_destroy(cache, slabp);
+		nr_freed++;
+	}
+out:
+	return nr_freed;
+}
+
+/* Called with cache_chain_mutex held to protect against cpu hotplug */
+static int __cache_shrink(struct kmem_cache *cachep)
+{
+	int ret = 0, i = 0;
+	struct kmem_list3 *l3;
+
+	drain_cpu_caches(cachep);
+
+	check_irq_on();
+	for_each_online_node(i) {
+		l3 = cachep->nodelists[i];
+		if (!l3)
+			continue;
+
+		drain_freelist(cachep, l3, l3->free_objects);
+
+		ret += !list_empty(&l3->slabs_full) ||
+			!list_empty(&l3->slabs_partial);
+	}
+	return (ret ? 1 : 0);
+}
+
+/**
+ * kmem_cache_shrink - Shrink a cache.
+ * @cachep: The cache to shrink.
+ *
+ * Releases as many slabs as possible for a cache.
+ * To help debugging, a zero exit status indicates all slabs were released.
+ */
+int kmem_cache_shrink(struct kmem_cache *cachep)
+{
+	int ret;
+	BUG_ON(!cachep || in_interrupt());
+
+	get_online_cpus();
+	mutex_lock(&cache_chain_mutex);
+	ret = __cache_shrink(cachep);
+	mutex_unlock(&cache_chain_mutex);
+	put_online_cpus();
+	return ret;
+}
+EXPORT_SYMBOL(kmem_cache_shrink);
+
+/**
+ * kmem_cache_destroy - delete a cache
+ * @cachep: the cache to destroy
+ *
+ * Remove a &struct kmem_cache object from the slab cache.
+ *
+ * It is expected this function will be called by a module when it is
+ * unloaded.  This will remove the cache completely, and avoid a duplicate
+ * cache being allocated each time a module is loaded and unloaded, if the
+ * module doesn't have persistent in-kernel storage across loads and unloads.
+ *
+ * The cache must be empty before calling this function.
+ *
+ * The caller must guarantee that no one will allocate memory from the cache
+ * during the kmem_cache_destroy().
+ */
+void kmem_cache_destroy(struct kmem_cache *cachep)
+{
+	BUG_ON(!cachep || in_interrupt());
+
+	/* Find the cache in the chain of caches. */
+	get_online_cpus();
+	mutex_lock(&cache_chain_mutex);
+	/*
+	 * the chain is never empty, cache_cache is never destroyed
+	 */
+	list_del(&cachep->next);
+	if (__cache_shrink(cachep)) {
+		slab_error(cachep, "Can't free all objects");
+		list_add(&cachep->next, &cache_chain);
+		mutex_unlock(&cache_chain_mutex);
+		put_online_cpus();
+		return;
+	}
+
+	if (unlikely(cachep->flags & SLAB_DESTROY_BY_RCU))
+		rcu_barrier();
+
+	__kmem_cache_destroy(cachep);
+	mutex_unlock(&cache_chain_mutex);
+	put_online_cpus();
+}
+EXPORT_SYMBOL(kmem_cache_destroy);
+
+/*
+ * Get the memory for a slab management obj.
+ * For a slab cache when the slab descriptor is off-slab, slab descriptors
+ * always come from malloc_sizes caches.  The slab descriptor cannot
+ * come from the same cache which is getting created because,
+ * when we are searching for an appropriate cache for these
+ * descriptors in kmem_cache_create, we search through the malloc_sizes array.
+ * If we are creating a malloc_sizes cache here it would not be visible to
+ * kmem_find_general_cachep till the initialization is complete.
+ * Hence we cannot have slabp_cache same as the original cache.
+ */
+static struct slab *alloc_slabmgmt(struct kmem_cache *cachep, void *objp,
+				   int colour_off, gfp_t local_flags,
+				   int nodeid)
+{
+	struct slab *slabp;
+
+	if (OFF_SLAB(cachep)) {
+		/* Slab management obj is off-slab. */
+		slabp = kmem_cache_alloc_node(cachep->slabp_cache,
+					      local_flags, nodeid);
+		/*
+		 * If the first object in the slab is leaked (it's allocated
+		 * but no one has a reference to it), we want to make sure
+		 * kmemleak does not treat the ->s_mem pointer as a reference
+		 * to the object. Otherwise we will not report the leak.
+		 */
+		kmemleak_scan_area(&slabp->list, sizeof(struct list_head),
+				   local_flags);
+		if (!slabp)
+			return NULL;
+	} else {
+		slabp = objp + colour_off;
+		colour_off += cachep->slab_size;
+	}
+	slabp->inuse = 0;
+	slabp->colouroff = colour_off;
+	slabp->s_mem = objp + colour_off;
+	slabp->nodeid = nodeid;
+	slabp->free = 0;
+	return slabp;
+}
+
+static inline kmem_bufctl_t *slab_bufctl(struct slab *slabp)
+{
+	return (kmem_bufctl_t *) (slabp + 1);
+}
+
+static void cache_init_objs(struct kmem_cache *cachep,
+			    struct slab *slabp)
+{
+	int i;
+
+	for (i = 0; i < cachep->num; i++) {
+		void *objp = index_to_obj(cachep, slabp, i);
+#if DEBUG
+		/* need to poison the objs? */
+		if (cachep->flags & SLAB_POISON)
+			poison_obj(cachep, objp, POISON_FREE);
+		if (cachep->flags & SLAB_STORE_USER)
+			*dbg_userword(cachep, objp) = NULL;
+
+		if (cachep->flags & SLAB_RED_ZONE) {
+			*dbg_redzone1(cachep, objp) = RED_INACTIVE;
+			*dbg_redzone2(cachep, objp) = RED_INACTIVE;
+		}
+		/*
+		 * Constructors are not allowed to allocate memory from the same
+		 * cache which they are a constructor for.  Otherwise, deadlock.
+		 * They must also be threaded.
+		 */
+		if (cachep->ctor && !(cachep->flags & SLAB_POISON))
+			cachep->ctor(objp + obj_offset(cachep));
+
+		if (cachep->flags & SLAB_RED_ZONE) {
+			if (*dbg_redzone2(cachep, objp) != RED_INACTIVE)
+				slab_error(cachep, "constructor overwrote the"
+					   " end of an object");
+			if (*dbg_redzone1(cachep, objp) != RED_INACTIVE)
+				slab_error(cachep, "constructor overwrote the"
+					   " start of an object");
+		}
+		if ((cachep->buffer_size % PAGE_SIZE) == 0 &&
+			    OFF_SLAB(cachep) && cachep->flags & SLAB_POISON)
+			kernel_map_pages(virt_to_page(objp),
+					 cachep->buffer_size / PAGE_SIZE, 0);
+#else
+		if (cachep->ctor)
+			cachep->ctor(objp);
+#endif
+		slab_bufctl(slabp)[i] = i + 1;
+	}
+	slab_bufctl(slabp)[i - 1] = BUFCTL_END;
+}
+
+static void kmem_flagcheck(struct kmem_cache *cachep, gfp_t flags)
+{
+	if (CONFIG_ZONE_DMA_FLAG) {
+		if (flags & GFP_DMA)
+			BUG_ON(!(cachep->gfpflags & GFP_DMA));
+		else
+			BUG_ON(cachep->gfpflags & GFP_DMA);
+	}
+}
+
+static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp,
+				int nodeid)
+{
+	void *objp = index_to_obj(cachep, slabp, slabp->free);
+	kmem_bufctl_t next;
+
+	slabp->inuse++;
+	next = slab_bufctl(slabp)[slabp->free];
+#if DEBUG
+	slab_bufctl(slabp)[slabp->free] = BUFCTL_FREE;
+	WARN_ON(slabp->nodeid != nodeid);
+#endif
+	slabp->free = next;
+
+	return objp;
+}
+
+static void slab_put_obj(struct kmem_cache *cachep, struct slab *slabp,
+				void *objp, int nodeid)
+{
+	unsigned int objnr = obj_to_index(cachep, slabp, objp);
+
+#if DEBUG
+	/* Verify that the slab belongs to the intended node */
+	WARN_ON(slabp->nodeid != nodeid);
+
+	if (slab_bufctl(slabp)[objnr] + 1 <= SLAB_LIMIT + 1) {
+		printk(KERN_ERR "slab: double free detected in cache "
+				"'%s', objp %p\n", cachep->name, objp);
+		BUG();
+	}
+#endif
+	slab_bufctl(slabp)[objnr] = slabp->free;
+	slabp->free = objnr;
+	slabp->inuse--;
+}
+
+/*
+ * Map pages beginning at addr to the given cache and slab. This is required
+ * for the slab allocator to be able to lookup the cache and slab of a
+ * virtual address for kfree, ksize, and slab debugging.
+ */
+static void slab_map_pages(struct kmem_cache *cache, struct slab *slab,
+			   void *addr)
+{
+	int nr_pages;
+	struct page *page;
+
+	page = virt_to_page(addr);
+
+	nr_pages = 1;
+	if (likely(!PageCompound(page)))
+		nr_pages <<= cache->gfporder;
+
+	do {
+		page_set_cache(page, cache);
+		page_set_slab(page, slab);
+		page++;
+	} while (--nr_pages);
+}
+
+/*
+ * Grow (by 1) the number of slabs within a cache.  This is called by
+ * kmem_cache_alloc() when there are no active objs left in a cache.
+ */
+static int cache_grow(struct kmem_cache *cachep,
+		gfp_t flags, int nodeid, void *objp)
+{
+	struct slab *slabp;
+	size_t offset;
+	gfp_t local_flags;
+	struct kmem_list3 *l3;
+
+	/*
+	 * Be lazy and only check for valid flags here,  keeping it out of the
+	 * critical path in kmem_cache_alloc().
+	 */
+	BUG_ON(flags & GFP_SLAB_BUG_MASK);
+	local_flags = flags & (GFP_CONSTRAINT_MASK|GFP_RECLAIM_MASK);
+
+	/* Take the l3 list lock to change the colour_next on this node */
+	check_irq_off();
+	l3 = cachep->nodelists[nodeid];
+	spin_lock(&l3->list_lock);
+
+	/* Get colour for the slab, and cal the next value. */
+	offset = l3->colour_next;
+	l3->colour_next++;
+	if (l3->colour_next >= cachep->colour)
+		l3->colour_next = 0;
+	spin_unlock(&l3->list_lock);
+
+	offset *= cachep->colour_off;
+
+	if (local_flags & __GFP_WAIT)
+		local_irq_enable();
+
+	/*
+	 * The test for missing atomic flag is performed here, rather than
+	 * the more obvious place, simply to reduce the critical path length
+	 * in kmem_cache_alloc(). If a caller is seriously mis-behaving they
+	 * will eventually be caught here (where it matters).
+	 */
+	kmem_flagcheck(cachep, flags);
+
+	/*
+	 * Get mem for the objs.  Attempt to allocate a physical page from
+	 * 'nodeid'.
+	 */
+	if (!objp)
+		objp = kmem_getpages(cachep, local_flags, nodeid);
+	if (!objp)
+		goto failed;
+
+	/* Get slab management. */
+	slabp = alloc_slabmgmt(cachep, objp, offset,
+			local_flags & ~GFP_CONSTRAINT_MASK, nodeid);
+	if (!slabp)
+		goto opps1;
+
+	slab_map_pages(cachep, slabp, objp);
+
+	cache_init_objs(cachep, slabp);
+
+	if (local_flags & __GFP_WAIT)
+		local_irq_disable();
+	check_irq_off();
+	spin_lock(&l3->list_lock);
+
+	/* Make slab active. */
+	list_add_tail(&slabp->list, &(l3->slabs_free));
+	STATS_INC_GROWN(cachep);
+	l3->free_objects += cachep->num;
+	spin_unlock(&l3->list_lock);
+	return 1;
+opps1:
+	kmem_freepages(cachep, objp);
+failed:
+	if (local_flags & __GFP_WAIT)
+		local_irq_disable();
+	return 0;
+}
+
+#if DEBUG
+
+/*
+ * Perform extra freeing checks:
+ * - detect bad pointers.
+ * - POISON/RED_ZONE checking
+ */
+static void kfree_debugcheck(const void *objp)
+{
+	if (!virt_addr_valid(objp)) {
+		printk(KERN_ERR "kfree_debugcheck: out of range ptr %lxh.\n",
+		       (unsigned long)objp);
+		BUG();
+	}
+}
+
+static inline void verify_redzone_free(struct kmem_cache *cache, void *obj)
+{
+	unsigned long long redzone1, redzone2;
+
+	redzone1 = *dbg_redzone1(cache, obj);
+	redzone2 = *dbg_redzone2(cache, obj);
+
+	/*
+	 * Redzone is ok.
+	 */
+	if (redzone1 == RED_ACTIVE && redzone2 == RED_ACTIVE)
+		return;
+
+	if (redzone1 == RED_INACTIVE && redzone2 == RED_INACTIVE)
+		slab_error(cache, "double free detected");
+	else
+		slab_error(cache, "memory outside object was overwritten");
+
+	printk(KERN_ERR "%p: redzone 1:0x%llx, redzone 2:0x%llx.\n",
+			obj, redzone1, redzone2);
+}
+
+static void *cache_free_debugcheck(struct kmem_cache *cachep, void *objp,
+				   void *caller)
+{
+	struct page *page;
+	unsigned int objnr;
+	struct slab *slabp;
+
+	BUG_ON(virt_to_cache(objp) != cachep);
+
+	objp -= obj_offset(cachep);
+	kfree_debugcheck(objp);
+	page = virt_to_head_page(objp);
+
+	slabp = page_get_slab(page);
+
+	if (cachep->flags & SLAB_RED_ZONE) {
+		verify_redzone_free(cachep, objp);
+		*dbg_redzone1(cachep, objp) = RED_INACTIVE;
+		*dbg_redzone2(cachep, objp) = RED_INACTIVE;
+	}
+	if (cachep->flags & SLAB_STORE_USER)
+		*dbg_userword(cachep, objp) = caller;
+
+	objnr = obj_to_index(cachep, slabp, objp);
+
+	BUG_ON(objnr >= cachep->num);
+	BUG_ON(objp != index_to_obj(cachep, slabp, objnr));
+
+#ifdef CONFIG_DEBUG_SLAB_LEAK
+	slab_bufctl(slabp)[objnr] = BUFCTL_FREE;
+#endif
+	if (cachep->flags & SLAB_POISON) {
+#ifdef CONFIG_DEBUG_PAGEALLOC
+		if ((cachep->buffer_size % PAGE_SIZE)==0 && OFF_SLAB(cachep)) {
+			store_stackinfo(cachep, objp, (unsigned long)caller);
+			kernel_map_pages(virt_to_page(objp),
+					 cachep->buffer_size / PAGE_SIZE, 0);
+		} else {
+			poison_obj(cachep, objp, POISON_FREE);
+		}
+#else
+		poison_obj(cachep, objp, POISON_FREE);
+#endif
+	}
+	return objp;
+}
+
+static void check_slabp(struct kmem_cache *cachep, struct slab *slabp)
+{
+	kmem_bufctl_t i;
+	int entries = 0;
+
+	/* Check slab's freelist to see if this obj is there. */
+	for (i = slabp->free; i != BUFCTL_END; i = slab_bufctl(slabp)[i]) {
+		entries++;
+		if (entries > cachep->num || i >= cachep->num)
+			goto bad;
+	}
+	if (entries != cachep->num - slabp->inuse) {
+bad:
+		printk(KERN_ERR "slab: Internal list corruption detected in "
+			"cache '%s'(%d), slabp %p(%d). Tainted(%s). Hexdump:\n",
+			cachep->name, cachep->num, slabp, slabp->inuse,
+			print_tainted());
+		print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 16, 1, slabp,
+			sizeof(*slabp) + cachep->num * sizeof(kmem_bufctl_t),
+			1);
+		BUG();
+	}
+}
+#else
+#define kfree_debugcheck(x) do { } while(0)
+#define cache_free_debugcheck(x,objp,z) (objp)
+#define check_slabp(x,y) do { } while(0)
+#endif
+
+static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
+{
+	int batchcount;
+	struct kmem_list3 *l3;
+	struct array_cache *ac;
+	int node;
+
+retry:
+	check_irq_off();
+	node = numa_mem_id();
+	ac = cpu_cache_get(cachep);
+	batchcount = ac->batchcount;
+	if (!ac->touched && batchcount > BATCHREFILL_LIMIT) {
+		/*
+		 * If there was little recent activity on this cache, then
+		 * perform only a partial refill.  Otherwise we could generate
+		 * refill bouncing.
+		 */
+		batchcount = BATCHREFILL_LIMIT;
+	}
+	l3 = cachep->nodelists[node];
+
+	BUG_ON(ac->avail > 0 || !l3);
+	spin_lock(&l3->list_lock);
+
+	/* See if we can refill from the shared array */
+	if (l3->shared && transfer_objects(ac, l3->shared, batchcount)) {
+		l3->shared->touched = 1;
+		goto alloc_done;
+	}
+
+	while (batchcount > 0) {
+		struct list_head *entry;
+		struct slab *slabp;
+		/* Get slab alloc is to come from. */
+		entry = l3->slabs_partial.next;
+		if (entry == &l3->slabs_partial) {
+			l3->free_touched = 1;
+			entry = l3->slabs_free.next;
+			if (entry == &l3->slabs_free)
+				goto must_grow;
+		}
+
+		slabp = list_entry(entry, struct slab, list);
+		check_slabp(cachep, slabp);
+		check_spinlock_acquired(cachep);
+
+		/*
+		 * The slab was either on partial or free list so
+		 * there must be at least one object available for
+		 * allocation.
+		 */
+		BUG_ON(slabp->inuse >= cachep->num);
+
+		while (slabp->inuse < cachep->num && batchcount--) {
+			STATS_INC_ALLOCED(cachep);
+			STATS_INC_ACTIVE(cachep);
+			STATS_SET_HIGH(cachep);
+
+			ac->entry[ac->avail++] = slab_get_obj(cachep, slabp,
+							    node);
+		}
+		check_slabp(cachep, slabp);
+
+		/* move slabp to correct slabp list: */
+		list_del(&slabp->list);
+		if (slabp->free == BUFCTL_END)
+			list_add(&slabp->list, &l3->slabs_full);
+		else
+			list_add(&slabp->list, &l3->slabs_partial);
+	}
+
+must_grow:
+	l3->free_objects -= ac->avail;
+alloc_done:
+	spin_unlock(&l3->list_lock);
+
+	if (unlikely(!ac->avail)) {
+		int x;
+		x = cache_grow(cachep, flags | GFP_THISNODE, node, NULL);
+
+		/* cache_grow can reenable interrupts, then ac could change. */
+		ac = cpu_cache_get(cachep);
+		if (!x && ac->avail == 0)	/* no objects in sight? abort */
+			return NULL;
+
+		if (!ac->avail)		/* objects refilled by interrupt? */
+			goto retry;
+	}
+	ac->touched = 1;
+	return ac->entry[--ac->avail];
+}
+
+static inline void cache_alloc_debugcheck_before(struct kmem_cache *cachep,
+						gfp_t flags)
+{
+	might_sleep_if(flags & __GFP_WAIT);
+#if DEBUG
+	kmem_flagcheck(cachep, flags);
+#endif
+}
+
+#if DEBUG
+static void *cache_alloc_debugcheck_after(struct kmem_cache *cachep,
+				gfp_t flags, void *objp, void *caller)
+{
+	if (!objp)
+		return objp;
+	if (cachep->flags & SLAB_POISON) {
+#ifdef CONFIG_DEBUG_PAGEALLOC
+		if ((cachep->buffer_size % PAGE_SIZE) == 0 && OFF_SLAB(cachep))
+			kernel_map_pages(virt_to_page(objp),
+					 cachep->buffer_size / PAGE_SIZE, 1);
+		else
+			check_poison_obj(cachep, objp);
+#else
+		check_poison_obj(cachep, objp);
+#endif
+		poison_obj(cachep, objp, POISON_INUSE);
+	}
+	if (cachep->flags & SLAB_STORE_USER)
+		*dbg_userword(cachep, objp) = caller;
+
+	if (cachep->flags & SLAB_RED_ZONE) {
+		if (*dbg_redzone1(cachep, objp) != RED_INACTIVE ||
+				*dbg_redzone2(cachep, objp) != RED_INACTIVE) {
+			slab_error(cachep, "double free, or memory outside"
+						" object was overwritten");
+			printk(KERN_ERR
+				"%p: redzone 1:0x%llx, redzone 2:0x%llx\n",
+				objp, *dbg_redzone1(cachep, objp),
+				*dbg_redzone2(cachep, objp));
+		}
+		*dbg_redzone1(cachep, objp) = RED_ACTIVE;
+		*dbg_redzone2(cachep, objp) = RED_ACTIVE;
+	}
+#ifdef CONFIG_DEBUG_SLAB_LEAK
+	{
+		struct slab *slabp;
+		unsigned objnr;
+
+		slabp = page_get_slab(virt_to_head_page(objp));
+		objnr = (unsigned)(objp - slabp->s_mem) / cachep->buffer_size;
+		slab_bufctl(slabp)[objnr] = BUFCTL_ACTIVE;
+	}
+#endif
+	objp += obj_offset(cachep);
+	if (cachep->ctor && cachep->flags & SLAB_POISON)
+		cachep->ctor(objp);
+	if (ARCH_SLAB_MINALIGN &&
+	    ((unsigned long)objp & (ARCH_SLAB_MINALIGN-1))) {
+		printk(KERN_ERR "0x%p: not aligned to ARCH_SLAB_MINALIGN=%d\n",
+		       objp, (int)ARCH_SLAB_MINALIGN);
+	}
+	return objp;
+}
+#else
+#define cache_alloc_debugcheck_after(a,b,objp,d) (objp)
+#endif
+
+static bool slab_should_failslab(struct kmem_cache *cachep, gfp_t flags)
+{
+	if (cachep == &cache_cache)
+		return false;
+
+	return should_failslab(obj_size(cachep), flags, cachep->flags);
+}
+
+static inline void *____cache_alloc(struct kmem_cache *cachep, gfp_t flags)
+{
+	void *objp;
+	struct array_cache *ac;
+
+	check_irq_off();
+
+	ac = cpu_cache_get(cachep);
+	if (likely(ac->avail)) {
+		STATS_INC_ALLOCHIT(cachep);
+		ac->touched = 1;
+		objp = ac->entry[--ac->avail];
+	} else {
+		STATS_INC_ALLOCMISS(cachep);
+		objp = cache_alloc_refill(cachep, flags);
+		/*
+		 * the 'ac' may be updated by cache_alloc_refill(),
+		 * and kmemleak_erase() requires its correct value.
+		 */
+		ac = cpu_cache_get(cachep);
+	}
+	/*
+	 * To avoid a false negative, if an object that is in one of the
+	 * per-CPU caches is leaked, we need to make sure kmemleak doesn't
+	 * treat the array pointers as a reference to the object.
+	 */
+	if (objp)
+		kmemleak_erase(&ac->entry[ac->avail]);
+	return objp;
+}
+
+#ifdef CONFIG_NUMA
+/*
+ * Try allocating on another node if PF_SPREAD_SLAB|PF_MEMPOLICY.
+ *
+ * If we are in_interrupt, then process context, including cpusets and
+ * mempolicy, may not apply and should not be used for allocation policy.
+ */
+static void *alternate_node_alloc(struct kmem_cache *cachep, gfp_t flags)
+{
+	int nid_alloc, nid_here;
+
+	if (in_interrupt() || (flags & __GFP_THISNODE))
+		return NULL;
+	nid_alloc = nid_here = numa_mem_id();
+	if (cpuset_do_slab_mem_spread() && (cachep->flags & SLAB_MEM_SPREAD))
+		nid_alloc = cpuset_slab_spread_node();
+	else if (current->mempolicy)
+		nid_alloc = slab_node(current->mempolicy);
+	if (nid_alloc != nid_here)
+		return ____cache_alloc_node(cachep, flags, nid_alloc);
+	return NULL;
+}
+
+/*
+ * Fallback function if there was no memory available and no objects on a
+ * certain node and fall back is permitted. First we scan all the
+ * available nodelists for available objects. If that fails then we
+ * perform an allocation without specifying a node. This allows the page
+ * allocator to do its reclaim / fallback magic. We then insert the
+ * slab into the proper nodelist and then allocate from it.
+ */
+static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags)
+{
+	struct zonelist *zonelist;
+	gfp_t local_flags;
+	struct zoneref *z;
+	struct zone *zone;
+	enum zone_type high_zoneidx = gfp_zone(flags);
+	void *obj = NULL;
+	int nid;
+	unsigned int cpuset_mems_cookie;
+
+	if (flags & __GFP_THISNODE)
+		return NULL;
+
+	local_flags = flags & (GFP_CONSTRAINT_MASK|GFP_RECLAIM_MASK);
+
+retry_cpuset:
+	cpuset_mems_cookie = get_mems_allowed();
+	zonelist = node_zonelist(slab_node(current->mempolicy), flags);
+
+retry:
+	/*
+	 * Look through allowed nodes for objects available
+	 * from existing per node queues.
+	 */
+	for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
+		nid = zone_to_nid(zone);
+
+		if (cpuset_zone_allowed_hardwall(zone, flags) &&
+			cache->nodelists[nid] &&
+			cache->nodelists[nid]->free_objects) {
+				obj = ____cache_alloc_node(cache,
+					flags | GFP_THISNODE, nid);
+				if (obj)
+					break;
+		}
+	}
+
+	if (!obj) {
+		/*
+		 * This allocation will be performed within the constraints
+		 * of the current cpuset / memory policy requirements.
+		 * We may trigger various forms of reclaim on the allowed
+		 * set and go into memory reserves if necessary.
+		 */
+		if (local_flags & __GFP_WAIT)
+			local_irq_enable();
+		kmem_flagcheck(cache, flags);
+		obj = kmem_getpages(cache, local_flags, numa_mem_id());
+		if (local_flags & __GFP_WAIT)
+			local_irq_disable();
+		if (obj) {
+			/*
+			 * Insert into the appropriate per node queues
+			 */
+			nid = page_to_nid(virt_to_page(obj));
+			if (cache_grow(cache, flags, nid, obj)) {
+				obj = ____cache_alloc_node(cache,
+					flags | GFP_THISNODE, nid);
+				if (!obj)
+					/*
+					 * Another processor may allocate the
+					 * objects in the slab since we are
+					 * not holding any locks.
+					 */
+					goto retry;
+			} else {
+				/* cache_grow already freed obj */
+				obj = NULL;
+			}
+		}
+	}
+
+	if (unlikely(!put_mems_allowed(cpuset_mems_cookie) && !obj))
+		goto retry_cpuset;
+	return obj;
+}
+
+/*
+ * A interface to enable slab creation on nodeid
+ */
+static void *____cache_alloc_node(struct kmem_cache *cachep, gfp_t flags,
+				int nodeid)
+{
+	struct list_head *entry;
+	struct slab *slabp;
+	struct kmem_list3 *l3;
+	void *obj;
+	int x;
+
+	l3 = cachep->nodelists[nodeid];
+	BUG_ON(!l3);
+
+retry:
+	check_irq_off();
+	spin_lock(&l3->list_lock);
+	entry = l3->slabs_partial.next;
+	if (entry == &l3->slabs_partial) {
+		l3->free_touched = 1;
+		entry = l3->slabs_free.next;
+		if (entry == &l3->slabs_free)
+			goto must_grow;
+	}
+
+	slabp = list_entry(entry, struct slab, list);
+	check_spinlock_acquired_node(cachep, nodeid);
+	check_slabp(cachep, slabp);
+
+	STATS_INC_NODEALLOCS(cachep);
+	STATS_INC_ACTIVE(cachep);
+	STATS_SET_HIGH(cachep);
+
+	BUG_ON(slabp->inuse == cachep->num);
+
+	obj = slab_get_obj(cachep, slabp, nodeid);
+	check_slabp(cachep, slabp);
+	l3->free_objects--;
+	/* move slabp to correct slabp list: */
+	list_del(&slabp->list);
+
+	if (slabp->free == BUFCTL_END)
+		list_add(&slabp->list, &l3->slabs_full);
+	else
+		list_add(&slabp->list, &l3->slabs_partial);
+
+	spin_unlock(&l3->list_lock);
+	goto done;
+
+must_grow:
+	spin_unlock(&l3->list_lock);
+	x = cache_grow(cachep, flags | GFP_THISNODE, nodeid, NULL);
+	if (x)
+		goto retry;
+
+	return fallback_alloc(cachep, flags);
+
+done:
+	return obj;
+}
+
+/**
+ * kmem_cache_alloc_node - Allocate an object on the specified node
+ * @cachep: The cache to allocate from.
+ * @flags: See kmalloc().
+ * @nodeid: node number of the target node.
+ * @caller: return address of caller, used for debug information
+ *
+ * Identical to kmem_cache_alloc but it will allocate memory on the given
+ * node, which can improve the performance for cpu bound structures.
+ *
+ * Fallback to other node is possible if __GFP_THISNODE is not set.
+ */
+static __always_inline void *
+__cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid,
+		   void *caller)
+{
+	unsigned long save_flags;
+	void *ptr;
+	int slab_node = numa_mem_id();
+
+	flags &= gfp_allowed_mask;
+
+	lockdep_trace_alloc(flags);
+
+	if (slab_should_failslab(cachep, flags))
+		return NULL;
+
+	cache_alloc_debugcheck_before(cachep, flags);
+	local_irq_save(save_flags);
+
+	if (nodeid == NUMA_NO_NODE)
+		nodeid = slab_node;
+
+	if (unlikely(!cachep->nodelists[nodeid])) {
+		/* Node not bootstrapped yet */
+		ptr = fallback_alloc(cachep, flags);
+		goto out;
+	}
+
+	if (nodeid == slab_node) {
+		/*
+		 * Use the locally cached objects if possible.
+		 * However ____cache_alloc does not allow fallback
+		 * to other nodes. It may fail while we still have
+		 * objects on other nodes available.
+		 */
+		ptr = ____cache_alloc(cachep, flags);
+		if (ptr)
+			goto out;
+	}
+	/* ___cache_alloc_node can fall back to other nodes */
+	ptr = ____cache_alloc_node(cachep, flags, nodeid);
+  out:
+	local_irq_restore(save_flags);
+	ptr = cache_alloc_debugcheck_after(cachep, flags, ptr, caller);
+	kmemleak_alloc_recursive(ptr, obj_size(cachep), 1, cachep->flags,
+				 flags);
+
+	if (likely(ptr))
+		kmemcheck_slab_alloc(cachep, flags, ptr, obj_size(cachep));
+
+	if (unlikely((flags & __GFP_ZERO) && ptr))
+		memset(ptr, 0, obj_size(cachep));
+
+	return ptr;
+}
+
+static __always_inline void *
+__do_cache_alloc(struct kmem_cache *cache, gfp_t flags)
+{
+	void *objp;
+
+	if (unlikely(current->flags & (PF_SPREAD_SLAB | PF_MEMPOLICY))) {
+		objp = alternate_node_alloc(cache, flags);
+		if (objp)
+			goto out;
+	}
+	objp = ____cache_alloc(cache, flags);
+
+	/*
+	 * We may just have run out of memory on the local node.
+	 * ____cache_alloc_node() knows how to locate memory on other nodes
+	 */
+	if (!objp)
+		objp = ____cache_alloc_node(cache, flags, numa_mem_id());
+
+  out:
+	return objp;
+}
+#else
+
+static __always_inline void *
+__do_cache_alloc(struct kmem_cache *cachep, gfp_t flags)
+{
+	return ____cache_alloc(cachep, flags);
+}
+
+#endif /* CONFIG_NUMA */
+
+static __always_inline void *
+__cache_alloc(struct kmem_cache *cachep, gfp_t flags, void *caller)
+{
+	unsigned long save_flags;
+	void *objp;
+
+	flags &= gfp_allowed_mask;
+
+	lockdep_trace_alloc(flags);
+
+	if (slab_should_failslab(cachep, flags))
+		return NULL;
+
+	cache_alloc_debugcheck_before(cachep, flags);
+	local_irq_save(save_flags);
+	objp = __do_cache_alloc(cachep, flags);
+	local_irq_restore(save_flags);
+	objp = cache_alloc_debugcheck_after(cachep, flags, objp, caller);
+	kmemleak_alloc_recursive(objp, obj_size(cachep), 1, cachep->flags,
+				 flags);
+	prefetchw(objp);
+
+	if (likely(objp))
+		kmemcheck_slab_alloc(cachep, flags, objp, obj_size(cachep));
+
+	if (unlikely((flags & __GFP_ZERO) && objp))
+		memset(objp, 0, obj_size(cachep));
+
+	return objp;
+}
+
+/*
+ * Caller needs to acquire correct kmem_list's list_lock
+ */
+static void free_block(struct kmem_cache *cachep, void **objpp, int nr_objects,
+		       int node)
+{
+	int i;
+	struct kmem_list3 *l3;
+
+	for (i = 0; i < nr_objects; i++) {
+		void *objp = objpp[i];
+		struct slab *slabp;
+
+		slabp = virt_to_slab(objp);
+		l3 = cachep->nodelists[node];
+		list_del(&slabp->list);
+		check_spinlock_acquired_node(cachep, node);
+		check_slabp(cachep, slabp);
+		slab_put_obj(cachep, slabp, objp, node);
+		STATS_DEC_ACTIVE(cachep);
+		l3->free_objects++;
+		check_slabp(cachep, slabp);
+
+		/* fixup slab chains */
+		if (slabp->inuse == 0) {
+			if (l3->free_objects > l3->free_limit) {
+				l3->free_objects -= cachep->num;
+				/* No need to drop any previously held
+				 * lock here, even if we have a off-slab slab
+				 * descriptor it is guaranteed to come from
+				 * a different cache, refer to comments before
+				 * alloc_slabmgmt.
+				 */
+				slab_destroy(cachep, slabp);
+			} else {
+				list_add(&slabp->list, &l3->slabs_free);
+			}
+		} else {
+			/* Unconditionally move a slab to the end of the
+			 * partial list on free - maximum time for the
+			 * other objects to be freed, too.
+			 */
+			list_add_tail(&slabp->list, &l3->slabs_partial);
+		}
+	}
+}
+
+static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac)
+{
+	int batchcount;
+	struct kmem_list3 *l3;
+	int node = numa_mem_id();
+
+	batchcount = ac->batchcount;
+#if DEBUG
+	BUG_ON(!batchcount || batchcount > ac->avail);
+#endif
+	check_irq_off();
+	l3 = cachep->nodelists[node];
+	spin_lock(&l3->list_lock);
+	if (l3->shared) {
+		struct array_cache *shared_array = l3->shared;
+		int max = shared_array->limit - shared_array->avail;
+		if (max) {
+			if (batchcount > max)
+				batchcount = max;
+			memcpy(&(shared_array->entry[shared_array->avail]),
+			       ac->entry, sizeof(void *) * batchcount);
+			shared_array->avail += batchcount;
+			goto free_done;
+		}
+	}
+
+	free_block(cachep, ac->entry, batchcount, node);
+free_done:
+#if STATS
+	{
+		int i = 0;
+		struct list_head *p;
+
+		p = l3->slabs_free.next;
+		while (p != &(l3->slabs_free)) {
+			struct slab *slabp;
+
+			slabp = list_entry(p, struct slab, list);
+			BUG_ON(slabp->inuse);
+
+			i++;
+			p = p->next;
+		}
+		STATS_SET_FREEABLE(cachep, i);
+	}
+#endif
+	spin_unlock(&l3->list_lock);
+	ac->avail -= batchcount;
+	memmove(ac->entry, &(ac->entry[batchcount]), sizeof(void *)*ac->avail);
+}
+
+/*
+ * Release an obj back to its cache. If the obj has a constructed state, it must
+ * be in this state _before_ it is released.  Called with disabled ints.
+ */
+static inline void __cache_free(struct kmem_cache *cachep, void *objp,
+    void *caller)
+{
+	struct array_cache *ac = cpu_cache_get(cachep);
+
+	check_irq_off();
+	kmemleak_free_recursive(objp, cachep->flags);
+	objp = cache_free_debugcheck(cachep, objp, caller);
+
+	kmemcheck_slab_free(cachep, objp, obj_size(cachep));
+
+	/*
+	 * Skip calling cache_free_alien() when the platform is not numa.
+	 * This will avoid cache misses that happen while accessing slabp (which
+	 * is per page memory  reference) to get nodeid. Instead use a global
+	 * variable to skip the call, which is mostly likely to be present in
+	 * the cache.
+	 */
+	if (nr_online_nodes > 1 && cache_free_alien(cachep, objp))
+		return;
+
+	if (likely(ac->avail < ac->limit)) {
+		STATS_INC_FREEHIT(cachep);
+	} else {
+		STATS_INC_FREEMISS(cachep);
+		cache_flusharray(cachep, ac);
+	}
+
+	ac->entry[ac->avail++] = objp;
+}
+
+/**
+ * kmem_cache_alloc - Allocate an object
+ * @cachep: The cache to allocate from.
+ * @flags: See kmalloc().
+ *
+ * Allocate an object from this cache.  The flags are only relevant
+ * if the cache has no available objects.
+ */
+void *kmem_cache_alloc(struct kmem_cache *cachep, gfp_t flags)
+{
+	void *ret = __cache_alloc(cachep, flags, __builtin_return_address(0));
+
+	trace_kmem_cache_alloc(_RET_IP_, ret,
+			       obj_size(cachep), cachep->buffer_size, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL(kmem_cache_alloc);
+
+#ifdef CONFIG_TRACING
+void *
+kmem_cache_alloc_trace(size_t size, struct kmem_cache *cachep, gfp_t flags)
+{
+	void *ret;
+
+	ret = __cache_alloc(cachep, flags, __builtin_return_address(0));
+
+	trace_kmalloc(_RET_IP_, ret,
+		      size, slab_buffer_size(cachep), flags);
+	return ret;
+}
+EXPORT_SYMBOL(kmem_cache_alloc_trace);
+#endif
+
+#ifdef CONFIG_NUMA
+void *kmem_cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid)
+{
+	void *ret = __cache_alloc_node(cachep, flags, nodeid,
+				       __builtin_return_address(0));
+
+	trace_kmem_cache_alloc_node(_RET_IP_, ret,
+				    obj_size(cachep), cachep->buffer_size,
+				    flags, nodeid);
+
+	return ret;
+}
+EXPORT_SYMBOL(kmem_cache_alloc_node);
+
+#ifdef CONFIG_TRACING
+void *kmem_cache_alloc_node_trace(size_t size,
+				  struct kmem_cache *cachep,
+				  gfp_t flags,
+				  int nodeid)
+{
+	void *ret;
+
+	ret = __cache_alloc_node(cachep, flags, nodeid,
+				  __builtin_return_address(0));
+	trace_kmalloc_node(_RET_IP_, ret,
+			   size, slab_buffer_size(cachep),
+			   flags, nodeid);
+	return ret;
+}
+EXPORT_SYMBOL(kmem_cache_alloc_node_trace);
+#endif
+
+static __always_inline void *
+__do_kmalloc_node(size_t size, gfp_t flags, int node, void *caller)
+{
+	struct kmem_cache *cachep;
+
+	cachep = kmem_find_general_cachep(size, flags);
+	if (unlikely(ZERO_OR_NULL_PTR(cachep)))
+		return cachep;
+	return kmem_cache_alloc_node_trace(size, cachep, flags, node);
+}
+
+#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_TRACING)
+void *__kmalloc_node(size_t size, gfp_t flags, int node)
+{
+	return __do_kmalloc_node(size, flags, node,
+			__builtin_return_address(0));
+}
+EXPORT_SYMBOL(__kmalloc_node);
+
+void *__kmalloc_node_track_caller(size_t size, gfp_t flags,
+		int node, unsigned long caller)
+{
+	return __do_kmalloc_node(size, flags, node, (void *)caller);
+}
+EXPORT_SYMBOL(__kmalloc_node_track_caller);
+#else
+void *__kmalloc_node(size_t size, gfp_t flags, int node)
+{
+	return __do_kmalloc_node(size, flags, node, NULL);
+}
+EXPORT_SYMBOL(__kmalloc_node);
+#endif /* CONFIG_DEBUG_SLAB || CONFIG_TRACING */
+#endif /* CONFIG_NUMA */
+
+/**
+ * __do_kmalloc - allocate memory
+ * @size: how many bytes of memory are required.
+ * @flags: the type of memory to allocate (see kmalloc).
+ * @caller: function caller for debug tracking of the caller
+ */
+static __always_inline void *__do_kmalloc(size_t size, gfp_t flags,
+					  void *caller)
+{
+	struct kmem_cache *cachep;
+	void *ret;
+
+	/* If you want to save a few bytes .text space: replace
+	 * __ with kmem_.
+	 * Then kmalloc uses the uninlined functions instead of the inline
+	 * functions.
+	 */
+	cachep = __find_general_cachep(size, flags);
+	if (unlikely(ZERO_OR_NULL_PTR(cachep)))
+		return cachep;
+	ret = __cache_alloc(cachep, flags, caller);
+
+	trace_kmalloc((unsigned long) caller, ret,
+		      size, cachep->buffer_size, flags);
+
+	return ret;
+}
+
+
+#if defined(CONFIG_DEBUG_SLAB) || defined(CONFIG_TRACING)
+void *__kmalloc(size_t size, gfp_t flags)
+{
+	return __do_kmalloc(size, flags, __builtin_return_address(0));
+}
+EXPORT_SYMBOL(__kmalloc);
+
+void *__kmalloc_track_caller(size_t size, gfp_t flags, unsigned long caller)
+{
+	return __do_kmalloc(size, flags, (void *)caller);
+}
+EXPORT_SYMBOL(__kmalloc_track_caller);
+
+#else
+void *__kmalloc(size_t size, gfp_t flags)
+{
+	return __do_kmalloc(size, flags, NULL);
+}
+EXPORT_SYMBOL(__kmalloc);
+#endif
+
+/**
+ * kmem_cache_free - Deallocate an object
+ * @cachep: The cache the allocation was from.
+ * @objp: The previously allocated object.
+ *
+ * Free an object which was previously allocated from this
+ * cache.
+ */
+void kmem_cache_free(struct kmem_cache *cachep, void *objp)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	debug_check_no_locks_freed(objp, obj_size(cachep));
+	if (!(cachep->flags & SLAB_DEBUG_OBJECTS))
+		debug_check_no_obj_freed(objp, obj_size(cachep));
+	__cache_free(cachep, objp, __builtin_return_address(0));
+	local_irq_restore(flags);
+
+	trace_kmem_cache_free(_RET_IP_, objp);
+}
+EXPORT_SYMBOL(kmem_cache_free);
+
+/**
+ * kfree - free previously allocated memory
+ * @objp: pointer returned by kmalloc.
+ *
+ * If @objp is NULL, no operation is performed.
+ *
+ * Don't free memory not originally allocated by kmalloc()
+ * or you will run into trouble.
+ */
+void kfree(const void *objp)
+{
+	struct kmem_cache *c;
+	unsigned long flags;
+
+	trace_kfree(_RET_IP_, objp);
+
+	if (unlikely(ZERO_OR_NULL_PTR(objp)))
+		return;
+	local_irq_save(flags);
+	kfree_debugcheck(objp);
+	c = virt_to_cache(objp);
+	debug_check_no_locks_freed(objp, obj_size(c));
+	debug_check_no_obj_freed(objp, obj_size(c));
+	__cache_free(c, (void *)objp, __builtin_return_address(0));
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL(kfree);
+
+unsigned int kmem_cache_size(struct kmem_cache *cachep)
+{
+	return obj_size(cachep);
+}
+EXPORT_SYMBOL(kmem_cache_size);
+
+/*
+ * This initializes kmem_list3 or resizes various caches for all nodes.
+ */
+static int alloc_kmemlist(struct kmem_cache *cachep, gfp_t gfp)
+{
+	int node;
+	struct kmem_list3 *l3;
+	struct array_cache *new_shared;
+	struct array_cache **new_alien = NULL;
+
+	for_each_online_node(node) {
+
+                if (use_alien_caches) {
+                        new_alien = alloc_alien_cache(node, cachep->limit, gfp);
+                        if (!new_alien)
+                                goto fail;
+                }
+
+		new_shared = NULL;
+		if (cachep->shared) {
+			new_shared = alloc_arraycache(node,
+				cachep->shared*cachep->batchcount,
+					0xbaadf00d, gfp);
+			if (!new_shared) {
+				free_alien_cache(new_alien);
+				goto fail;
+			}
+		}
+
+		l3 = cachep->nodelists[node];
+		if (l3) {
+			struct array_cache *shared = l3->shared;
+
+			spin_lock_irq(&l3->list_lock);
+
+			if (shared)
+				free_block(cachep, shared->entry,
+						shared->avail, node);
+
+			l3->shared = new_shared;
+			if (!l3->alien) {
+				l3->alien = new_alien;
+				new_alien = NULL;
+			}
+			l3->free_limit = (1 + nr_cpus_node(node)) *
+					cachep->batchcount + cachep->num;
+			spin_unlock_irq(&l3->list_lock);
+			kfree(shared);
+			free_alien_cache(new_alien);
+			continue;
+		}
+		l3 = kmalloc_node(sizeof(struct kmem_list3), gfp, node);
+		if (!l3) {
+			free_alien_cache(new_alien);
+			kfree(new_shared);
+			goto fail;
+		}
+
+		kmem_list3_init(l3);
+		l3->next_reap = jiffies + REAPTIMEOUT_LIST3 +
+				((unsigned long)cachep) % REAPTIMEOUT_LIST3;
+		l3->shared = new_shared;
+		l3->alien = new_alien;
+		l3->free_limit = (1 + nr_cpus_node(node)) *
+					cachep->batchcount + cachep->num;
+		cachep->nodelists[node] = l3;
+	}
+	return 0;
+
+fail:
+	if (!cachep->next.next) {
+		/* Cache is not active yet. Roll back what we did */
+		node--;
+		while (node >= 0) {
+			if (cachep->nodelists[node]) {
+				l3 = cachep->nodelists[node];
+
+				kfree(l3->shared);
+				free_alien_cache(l3->alien);
+				kfree(l3);
+				cachep->nodelists[node] = NULL;
+			}
+			node--;
+		}
+	}
+	return -ENOMEM;
+}
+
+struct ccupdate_struct {
+	struct kmem_cache *cachep;
+	struct array_cache *new[0];
+};
+
+static void do_ccupdate_local(void *info)
+{
+	struct ccupdate_struct *new = info;
+	struct array_cache *old;
+
+	check_irq_off();
+	old = cpu_cache_get(new->cachep);
+
+	new->cachep->array[smp_processor_id()] = new->new[smp_processor_id()];
+	new->new[smp_processor_id()] = old;
+}
+
+/* Always called with the cache_chain_mutex held */
+static int do_tune_cpucache(struct kmem_cache *cachep, int limit,
+				int batchcount, int shared, gfp_t gfp)
+{
+	struct ccupdate_struct *new;
+	int i;
+
+	new = kzalloc(sizeof(*new) + nr_cpu_ids * sizeof(struct array_cache *),
+		      gfp);
+	if (!new)
+		return -ENOMEM;
+
+	for_each_online_cpu(i) {
+		new->new[i] = alloc_arraycache(cpu_to_mem(i), limit,
+						batchcount, gfp);
+		if (!new->new[i]) {
+			for (i--; i >= 0; i--)
+				kfree(new->new[i]);
+			kfree(new);
+			return -ENOMEM;
+		}
+	}
+	new->cachep = cachep;
+
+	on_each_cpu(do_ccupdate_local, (void *)new, 1);
+
+	check_irq_on();
+	cachep->batchcount = batchcount;
+	cachep->limit = limit;
+	cachep->shared = shared;
+
+	for_each_online_cpu(i) {
+		struct array_cache *ccold = new->new[i];
+		if (!ccold)
+			continue;
+		spin_lock_irq(&cachep->nodelists[cpu_to_mem(i)]->list_lock);
+		free_block(cachep, ccold->entry, ccold->avail, cpu_to_mem(i));
+		spin_unlock_irq(&cachep->nodelists[cpu_to_mem(i)]->list_lock);
+		kfree(ccold);
+	}
+	kfree(new);
+	return alloc_kmemlist(cachep, gfp);
+}
+
+/* Called with cache_chain_mutex held always */
+static int enable_cpucache(struct kmem_cache *cachep, gfp_t gfp)
+{
+	int err;
+	int limit, shared;
+
+	/*
+	 * The head array serves three purposes:
+	 * - create a LIFO ordering, i.e. return objects that are cache-warm
+	 * - reduce the number of spinlock operations.
+	 * - reduce the number of linked list operations on the slab and
+	 *   bufctl chains: array operations are cheaper.
+	 * The numbers are guessed, we should auto-tune as described by
+	 * Bonwick.
+	 */
+	if (cachep->buffer_size > 131072)
+		limit = 1;
+	else if (cachep->buffer_size > PAGE_SIZE)
+		limit = 8;
+	else if (cachep->buffer_size > 1024)
+		limit = 24;
+	else if (cachep->buffer_size > 256)
+		limit = 54;
+	else
+		limit = 120;
+
+	/*
+	 * CPU bound tasks (e.g. network routing) can exhibit cpu bound
+	 * allocation behaviour: Most allocs on one cpu, most free operations
+	 * on another cpu. For these cases, an efficient object passing between
+	 * cpus is necessary. This is provided by a shared array. The array
+	 * replaces Bonwick's magazine layer.
+	 * On uniprocessor, it's functionally equivalent (but less efficient)
+	 * to a larger limit. Thus disabled by default.
+	 */
+	shared = 0;
+	if (cachep->buffer_size <= PAGE_SIZE && num_possible_cpus() > 1)
+		shared = 8;
+
+#if DEBUG
+	/*
+	 * With debugging enabled, large batchcount lead to excessively long
+	 * periods with disabled local interrupts. Limit the batchcount
+	 */
+	if (limit > 32)
+		limit = 32;
+#endif
+	err = do_tune_cpucache(cachep, limit, (limit + 1) / 2, shared, gfp);
+	if (err)
+		printk(KERN_ERR "enable_cpucache failed for %s, error %d.\n",
+		       cachep->name, -err);
+	return err;
+}
+
+/*
+ * Drain an array if it contains any elements taking the l3 lock only if
+ * necessary. Note that the l3 listlock also protects the array_cache
+ * if drain_array() is used on the shared array.
+ */
+static void drain_array(struct kmem_cache *cachep, struct kmem_list3 *l3,
+			 struct array_cache *ac, int force, int node)
+{
+	int tofree;
+
+	if (!ac || !ac->avail)
+		return;
+	if (ac->touched && !force) {
+		ac->touched = 0;
+	} else {
+		spin_lock_irq(&l3->list_lock);
+		if (ac->avail) {
+			tofree = force ? ac->avail : (ac->limit + 4) / 5;
+			if (tofree > ac->avail)
+				tofree = (ac->avail + 1) / 2;
+			free_block(cachep, ac->entry, tofree, node);
+			ac->avail -= tofree;
+			memmove(ac->entry, &(ac->entry[tofree]),
+				sizeof(void *) * ac->avail);
+		}
+		spin_unlock_irq(&l3->list_lock);
+	}
+}
+
+/**
+ * cache_reap - Reclaim memory from caches.
+ * @w: work descriptor
+ *
+ * Called from workqueue/eventd every few seconds.
+ * Purpose:
+ * - clear the per-cpu caches for this CPU.
+ * - return freeable pages to the main free memory pool.
+ *
+ * If we cannot acquire the cache chain mutex then just give up - we'll try
+ * again on the next iteration.
+ */
+static void cache_reap(struct work_struct *w)
+{
+	struct kmem_cache *searchp;
+	struct kmem_list3 *l3;
+	int node = numa_mem_id();
+	struct delayed_work *work = to_delayed_work(w);
+
+	if (!mutex_trylock(&cache_chain_mutex))
+		/* Give up. Setup the next iteration. */
+		goto out;
+
+	list_for_each_entry(searchp, &cache_chain, next) {
+		check_irq_on();
+
+		/*
+		 * We only take the l3 lock if absolutely necessary and we
+		 * have established with reasonable certainty that
+		 * we can do some work if the lock was obtained.
+		 */
+		l3 = searchp->nodelists[node];
+
+		reap_alien(searchp, l3);
+
+		drain_array(searchp, l3, cpu_cache_get(searchp), 0, node);
+
+		/*
+		 * These are racy checks but it does not matter
+		 * if we skip one check or scan twice.
+		 */
+		if (time_after(l3->next_reap, jiffies))
+			goto next;
+
+		l3->next_reap = jiffies + REAPTIMEOUT_LIST3;
+
+		drain_array(searchp, l3, l3->shared, 0, node);
+
+		if (l3->free_touched)
+			l3->free_touched = 0;
+		else {
+			int freed;
+
+			freed = drain_freelist(searchp, l3, (l3->free_limit +
+				5 * searchp->num - 1) / (5 * searchp->num));
+			STATS_ADD_REAPED(searchp, freed);
+		}
+next:
+		cond_resched();
+	}
+	check_irq_on();
+	mutex_unlock(&cache_chain_mutex);
+	next_reap_node();
+out:
+	/* Set up the next iteration */
+	schedule_delayed_work(work, round_jiffies_relative(REAPTIMEOUT_CPUC));
+}
+
+#ifdef CONFIG_SLABINFO
+
+static void print_slabinfo_header(struct seq_file *m)
+{
+	/*
+	 * Output format version, so at least we can change it
+	 * without _too_ many complaints.
+	 */
+#if STATS
+	seq_puts(m, "slabinfo - version: 2.1 (statistics)\n");
+#else
+	seq_puts(m, "slabinfo - version: 2.1\n");
+#endif
+	seq_puts(m, "# name            <active_objs> <num_objs> <objsize> "
+		 "<objperslab> <pagesperslab>");
+	seq_puts(m, " : tunables <limit> <batchcount> <sharedfactor>");
+	seq_puts(m, " : slabdata <active_slabs> <num_slabs> <sharedavail>");
+#if STATS
+	seq_puts(m, " : globalstat <listallocs> <maxobjs> <grown> <reaped> "
+		 "<error> <maxfreeable> <nodeallocs> <remotefrees> <alienoverflow>");
+	seq_puts(m, " : cpustat <allochit> <allocmiss> <freehit> <freemiss>");
+#endif
+	seq_putc(m, '\n');
+}
+
+static void *s_start(struct seq_file *m, loff_t *pos)
+{
+	loff_t n = *pos;
+
+	mutex_lock(&cache_chain_mutex);
+	if (!n)
+		print_slabinfo_header(m);
+
+	return seq_list_start(&cache_chain, *pos);
+}
+
+static void *s_next(struct seq_file *m, void *p, loff_t *pos)
+{
+	return seq_list_next(p, &cache_chain, pos);
+}
+
+static void s_stop(struct seq_file *m, void *p)
+{
+	mutex_unlock(&cache_chain_mutex);
+}
+
+static int s_show(struct seq_file *m, void *p)
+{
+	struct kmem_cache *cachep = list_entry(p, struct kmem_cache, next);
+	struct slab *slabp;
+	unsigned long active_objs;
+	unsigned long num_objs;
+	unsigned long active_slabs = 0;
+	unsigned long num_slabs, free_objects = 0, shared_avail = 0;
+	const char *name;
+	char *error = NULL;
+	int node;
+	struct kmem_list3 *l3;
+
+	active_objs = 0;
+	num_slabs = 0;
+	for_each_online_node(node) {
+		l3 = cachep->nodelists[node];
+		if (!l3)
+			continue;
+
+		check_irq_on();
+		spin_lock_irq(&l3->list_lock);
+
+		list_for_each_entry(slabp, &l3->slabs_full, list) {
+			if (slabp->inuse != cachep->num && !error)
+				error = "slabs_full accounting error";
+			active_objs += cachep->num;
+			active_slabs++;
+		}
+		list_for_each_entry(slabp, &l3->slabs_partial, list) {
+			if (slabp->inuse == cachep->num && !error)
+				error = "slabs_partial inuse accounting error";
+			if (!slabp->inuse && !error)
+				error = "slabs_partial/inuse accounting error";
+			active_objs += slabp->inuse;
+			active_slabs++;
+		}
+		list_for_each_entry(slabp, &l3->slabs_free, list) {
+			if (slabp->inuse && !error)
+				error = "slabs_free/inuse accounting error";
+			num_slabs++;
+		}
+		free_objects += l3->free_objects;
+		if (l3->shared)
+			shared_avail += l3->shared->avail;
+
+		spin_unlock_irq(&l3->list_lock);
+	}
+	num_slabs += active_slabs;
+	num_objs = num_slabs * cachep->num;
+	if (num_objs - active_objs != free_objects && !error)
+		error = "free_objects accounting error";
+
+	name = cachep->name;
+	if (error)
+		printk(KERN_ERR "slab: cache %s error: %s\n", name, error);
+
+	seq_printf(m, "%-17s %6lu %6lu %6u %4u %4d",
+		   name, active_objs, num_objs, cachep->buffer_size,
+		   cachep->num, (1 << cachep->gfporder));
+	seq_printf(m, " : tunables %4u %4u %4u",
+		   cachep->limit, cachep->batchcount, cachep->shared);
+	seq_printf(m, " : slabdata %6lu %6lu %6lu",
+		   active_slabs, num_slabs, shared_avail);
+#if STATS
+	{			/* list3 stats */
+		unsigned long high = cachep->high_mark;
+		unsigned long allocs = cachep->num_allocations;
+		unsigned long grown = cachep->grown;
+		unsigned long reaped = cachep->reaped;
+		unsigned long errors = cachep->errors;
+		unsigned long max_freeable = cachep->max_freeable;
+		unsigned long node_allocs = cachep->node_allocs;
+		unsigned long node_frees = cachep->node_frees;
+		unsigned long overflows = cachep->node_overflow;
+
+		seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu "
+			   "%4lu %4lu %4lu %4lu %4lu",
+			   allocs, high, grown,
+			   reaped, errors, max_freeable, node_allocs,
+			   node_frees, overflows);
+	}
+	/* cpu stats */
+	{
+		unsigned long allochit = atomic_read(&cachep->allochit);
+		unsigned long allocmiss = atomic_read(&cachep->allocmiss);
+		unsigned long freehit = atomic_read(&cachep->freehit);
+		unsigned long freemiss = atomic_read(&cachep->freemiss);
+
+		seq_printf(m, " : cpustat %6lu %6lu %6lu %6lu",
+			   allochit, allocmiss, freehit, freemiss);
+	}
+#endif
+	seq_putc(m, '\n');
+	return 0;
+}
+
+/*
+ * slabinfo_op - iterator that generates /proc/slabinfo
+ *
+ * Output layout:
+ * cache-name
+ * num-active-objs
+ * total-objs
+ * object size
+ * num-active-slabs
+ * total-slabs
+ * num-pages-per-slab
+ * + further values on SMP and with statistics enabled
+ */
+
+static const struct seq_operations slabinfo_op = {
+	.start = s_start,
+	.next = s_next,
+	.stop = s_stop,
+	.show = s_show,
+};
+
+#define MAX_SLABINFO_WRITE 128
+/**
+ * slabinfo_write - Tuning for the slab allocator
+ * @file: unused
+ * @buffer: user buffer
+ * @count: data length
+ * @ppos: unused
+ */
+static ssize_t slabinfo_write(struct file *file, const char __user *buffer,
+		       size_t count, loff_t *ppos)
+{
+	char kbuf[MAX_SLABINFO_WRITE + 1], *tmp;
+	int limit, batchcount, shared, res;
+	struct kmem_cache *cachep;
+
+	if (count > MAX_SLABINFO_WRITE)
+		return -EINVAL;
+	if (copy_from_user(&kbuf, buffer, count))
+		return -EFAULT;
+	kbuf[MAX_SLABINFO_WRITE] = '\0';
+
+	tmp = strchr(kbuf, ' ');
+	if (!tmp)
+		return -EINVAL;
+	*tmp = '\0';
+	tmp++;
+	if (sscanf(tmp, " %d %d %d", &limit, &batchcount, &shared) != 3)
+		return -EINVAL;
+
+	/* Find the cache in the chain of caches. */
+	mutex_lock(&cache_chain_mutex);
+	res = -EINVAL;
+	list_for_each_entry(cachep, &cache_chain, next) {
+		if (!strcmp(cachep->name, kbuf)) {
+			if (limit < 1 || batchcount < 1 ||
+					batchcount > limit || shared < 0) {
+				res = 0;
+			} else {
+				res = do_tune_cpucache(cachep, limit,
+						       batchcount, shared,
+						       GFP_KERNEL);
+			}
+			break;
+		}
+	}
+	mutex_unlock(&cache_chain_mutex);
+	if (res >= 0)
+		res = count;
+	return res;
+}
+
+static int slabinfo_open(struct inode *inode, struct file *file)
+{
+	return seq_open(file, &slabinfo_op);
+}
+
+static const struct file_operations proc_slabinfo_operations = {
+	.open		= slabinfo_open,
+	.read		= seq_read,
+	.write		= slabinfo_write,
+	.llseek		= seq_lseek,
+	.release	= seq_release,
+};
+
+#ifdef CONFIG_DEBUG_SLAB_LEAK
+
+static void *leaks_start(struct seq_file *m, loff_t *pos)
+{
+	mutex_lock(&cache_chain_mutex);
+	return seq_list_start(&cache_chain, *pos);
+}
+
+static inline int add_caller(unsigned long *n, unsigned long v)
+{
+	unsigned long *p;
+	int l;
+	if (!v)
+		return 1;
+	l = n[1];
+	p = n + 2;
+	while (l) {
+		int i = l/2;
+		unsigned long *q = p + 2 * i;
+		if (*q == v) {
+			q[1]++;
+			return 1;
+		}
+		if (*q > v) {
+			l = i;
+		} else {
+			p = q + 2;
+			l -= i + 1;
+		}
+	}
+	if (++n[1] == n[0])
+		return 0;
+	memmove(p + 2, p, n[1] * 2 * sizeof(unsigned long) - ((void *)p - (void *)n));
+	p[0] = v;
+	p[1] = 1;
+	return 1;
+}
+
+static void handle_slab(unsigned long *n, struct kmem_cache *c, struct slab *s)
+{
+	void *p;
+	int i;
+	if (n[0] == n[1])
+		return;
+	for (i = 0, p = s->s_mem; i < c->num; i++, p += c->buffer_size) {
+		if (slab_bufctl(s)[i] != BUFCTL_ACTIVE)
+			continue;
+		if (!add_caller(n, (unsigned long)*dbg_userword(c, p)))
+			return;
+	}
+}
+
+static void show_symbol(struct seq_file *m, unsigned long address)
+{
+#ifdef CONFIG_KALLSYMS
+	unsigned long offset, size;
+	char modname[MODULE_NAME_LEN], name[KSYM_NAME_LEN];
+
+	if (lookup_symbol_attrs(address, &size, &offset, modname, name) == 0) {
+		seq_printf(m, "%s+%#lx/%#lx", name, offset, size);
+		if (modname[0])
+			seq_printf(m, " [%s]", modname);
+		return;
+	}
+#endif
+	seq_printf(m, "%p", (void *)address);
+}
+
+static int leaks_show(struct seq_file *m, void *p)
+{
+	struct kmem_cache *cachep = list_entry(p, struct kmem_cache, next);
+	struct slab *slabp;
+	struct kmem_list3 *l3;
+	const char *name;
+	unsigned long *n = m->private;
+	int node;
+	int i;
+
+	if (!(cachep->flags & SLAB_STORE_USER))
+		return 0;
+	if (!(cachep->flags & SLAB_RED_ZONE))
+		return 0;
+
+	/* OK, we can do it */
+
+	n[1] = 0;
+
+	for_each_online_node(node) {
+		l3 = cachep->nodelists[node];
+		if (!l3)
+			continue;
+
+		check_irq_on();
+		spin_lock_irq(&l3->list_lock);
+
+		list_for_each_entry(slabp, &l3->slabs_full, list)
+			handle_slab(n, cachep, slabp);
+		list_for_each_entry(slabp, &l3->slabs_partial, list)
+			handle_slab(n, cachep, slabp);
+		spin_unlock_irq(&l3->list_lock);
+	}
+	name = cachep->name;
+	if (n[0] == n[1]) {
+		/* Increase the buffer size */
+		mutex_unlock(&cache_chain_mutex);
+		m->private = kzalloc(n[0] * 4 * sizeof(unsigned long), GFP_KERNEL);
+		if (!m->private) {
+			/* Too bad, we are really out */
+			m->private = n;
+			mutex_lock(&cache_chain_mutex);
+			return -ENOMEM;
+		}
+		*(unsigned long *)m->private = n[0] * 2;
+		kfree(n);
+		mutex_lock(&cache_chain_mutex);
+		/* Now make sure this entry will be retried */
+		m->count = m->size;
+		return 0;
+	}
+	for (i = 0; i < n[1]; i++) {
+		seq_printf(m, "%s: %lu ", name, n[2*i+3]);
+		show_symbol(m, n[2*i+2]);
+		seq_putc(m, '\n');
+	}
+
+	return 0;
+}
+
+static const struct seq_operations slabstats_op = {
+	.start = leaks_start,
+	.next = s_next,
+	.stop = s_stop,
+	.show = leaks_show,
+};
+
+static int slabstats_open(struct inode *inode, struct file *file)
+{
+	unsigned long *n = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	int ret = -ENOMEM;
+	if (n) {
+		ret = seq_open(file, &slabstats_op);
+		if (!ret) {
+			struct seq_file *m = file->private_data;
+			*n = PAGE_SIZE / (2 * sizeof(unsigned long));
+			m->private = n;
+			n = NULL;
+		}
+		kfree(n);
+	}
+	return ret;
+}
+
+static const struct file_operations proc_slabstats_operations = {
+	.open		= slabstats_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= seq_release_private,
+};
+#endif
+
+static int __init slab_proc_init(void)
+{
+	proc_create("slabinfo",S_IWUSR|S_IRUSR,NULL,&proc_slabinfo_operations);
+#ifdef CONFIG_DEBUG_SLAB_LEAK
+	proc_create("slab_allocators", 0, NULL, &proc_slabstats_operations);
+#endif
+	return 0;
+}
+module_init(slab_proc_init);
+#endif
+
+/**
+ * ksize - get the actual amount of memory allocated for a given object
+ * @objp: Pointer to the object
+ *
+ * kmalloc may internally round up allocations and return more memory
+ * than requested. ksize() can be used to determine the actual amount of
+ * memory allocated. The caller may use this additional memory, even though
+ * a smaller amount of memory was initially specified with the kmalloc call.
+ * The caller must guarantee that objp points to a valid object previously
+ * allocated with either kmalloc() or kmem_cache_alloc(). The object
+ * must not be freed during the duration of the call.
+ */
+size_t ksize(const void *objp)
+{
+	BUG_ON(!objp);
+	if (unlikely(objp == ZERO_SIZE_PTR))
+		return 0;
+
+	return obj_size(virt_to_cache(objp));
+}
+EXPORT_SYMBOL(ksize);