1 files changed, 3144 insertions, 0 deletions

diff --git a/mm/slub.c b/mm/slub.c
new file mode 100644
index 000000000000..0cd56bd74b64
--- /dev/null
+++ b/mm/slub.c
@@ -0,0 +1,3144 @@
+/*
+ * SLUB: A slab allocator that limits cache line use instead of queuing
+ * objects in per cpu and per node lists.
+ *
+ * The allocator synchronizes using per slab locks and only
+ * uses a centralized lock to manage a pool of partial slabs.
+ *
+ * (C) 2007 SGI, Christoph Lameter <clameter@sgi.com>
+ */
+
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/bit_spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+#include <linux/cpu.h>
+#include <linux/cpuset.h>
+#include <linux/mempolicy.h>
+#include <linux/ctype.h>
+#include <linux/kallsyms.h>
+
+/*
+ * Lock order:
+ *   1. slab_lock(page)
+ *   2. slab->list_lock
+ *
+ *   The slab_lock protects operations on the object of a particular
+ *   slab and its metadata in the page struct. If the slab lock
+ *   has been taken then no allocations nor frees can be performed
+ *   on the objects in the slab nor can the slab be added or removed
+ *   from the partial or full lists since this would mean modifying
+ *   the page_struct of the slab.
+ *
+ *   The list_lock protects the partial and full list on each node and
+ *   the partial slab counter. If taken then no new slabs may be added or
+ *   removed from the lists nor make the number of partial slabs be modified.
+ *   (Note that the total number of slabs is an atomic value that may be
+ *   modified without taking the list lock).
+ *
+ *   The list_lock is a centralized lock and thus we avoid taking it as
+ *   much as possible. As long as SLUB does not have to handle partial
+ *   slabs, operations can continue without any centralized lock. F.e.
+ *   allocating a long series of objects that fill up slabs does not require
+ *   the list lock.
+ *
+ *   The lock order is sometimes inverted when we are trying to get a slab
+ *   off a list. We take the list_lock and then look for a page on the list
+ *   to use. While we do that objects in the slabs may be freed. We can
+ *   only operate on the slab if we have also taken the slab_lock. So we use
+ *   a slab_trylock() on the slab. If trylock was successful then no frees
+ *   can occur anymore and we can use the slab for allocations etc. If the
+ *   slab_trylock() does not succeed then frees are in progress in the slab and
+ *   we must stay away from it for a while since we may cause a bouncing
+ *   cacheline if we try to acquire the lock. So go onto the next slab.
+ *   If all pages are busy then we may allocate a new slab instead of reusing
+ *   a partial slab. A new slab has noone operating on it and thus there is
+ *   no danger of cacheline contention.
+ *
+ *   Interrupts are disabled during allocation and deallocation in order to
+ *   make the slab allocator safe to use in the context of an irq. In addition
+ *   interrupts are disabled to ensure that the processor does not change
+ *   while handling per_cpu slabs, due to kernel preemption.
+ *
+ * SLUB assigns one slab for allocation to each processor.
+ * Allocations only occur from these slabs called cpu slabs.
+ *
+ * Slabs with free elements are kept on a partial list.
+ * There is no list for full slabs. If an object in a full slab is
+ * freed then the slab will show up again on the partial lists.
+ * Otherwise there is no need to track full slabs unless we have to
+ * track full slabs for debugging purposes.
+ *
+ * Slabs are freed when they become empty. Teardown and setup is
+ * minimal so we rely on the page allocators per cpu caches for
+ * fast frees and allocs.
+ *
+ * Overloading of page flags that are otherwise used for LRU management.
+ *
+ * PageActive           The slab is used as a cpu cache. Allocations
+ *                      may be performed from the slab. The slab is not
+ *                      on any slab list and cannot be moved onto one.
+ *
+ * PageError            Slab requires special handling due to debug
+ *                      options set. This moves slab handling out of
+ *                      the fast path.
+ */
+
+/*
+ * Issues still to be resolved:
+ *
+ * - The per cpu array is updated for each new slab and and is a remote
+ *   cacheline for most nodes. This could become a bouncing cacheline given
+ *   enough frequent updates. There are 16 pointers in a cacheline.so at
+ *   max 16 cpus could compete. Likely okay.
+ *
+ * - Support PAGE_ALLOC_DEBUG. Should be easy to do.
+ *
+ * - Support DEBUG_SLAB_LEAK. Trouble is we do not know where the full
+ *   slabs are in SLUB.
+ *
+ * - SLAB_DEBUG_INITIAL is not supported but I have never seen a use of
+ *   it.
+ *
+ * - Variable sizing of the per node arrays
+ */
+
+/* Enable to test recovery from slab corruption on boot */
+#undef SLUB_RESILIENCY_TEST
+
+#if PAGE_SHIFT <= 12
+
+/*
+ * Small page size. Make sure that we do not fragment memory
+ */
+#define DEFAULT_MAX_ORDER 1
+#define DEFAULT_MIN_OBJECTS 4
+
+#else
+
+/*
+ * Large page machines are customarily able to handle larger
+ * page orders.
+ */
+#define DEFAULT_MAX_ORDER 2
+#define DEFAULT_MIN_OBJECTS 8
+
+#endif
+
+/*
+ * Flags from the regular SLAB that SLUB does not support:
+ */
+#define SLUB_UNIMPLEMENTED (SLAB_DEBUG_INITIAL)
+
+#define DEBUG_DEFAULT_FLAGS (SLAB_DEBUG_FREE | SLAB_RED_ZONE | \
+                                SLAB_POISON | SLAB_STORE_USER)
+/*
+ * Set of flags that will prevent slab merging
+ */
+#define SLUB_NEVER_MERGE (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
+                SLAB_TRACE | SLAB_DESTROY_BY_RCU)
+
+#define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \
+                SLAB_CACHE_DMA)
+
+#ifndef ARCH_KMALLOC_MINALIGN
+#define ARCH_KMALLOC_MINALIGN sizeof(void *)
+#endif
+
+#ifndef ARCH_SLAB_MINALIGN
+#define ARCH_SLAB_MINALIGN sizeof(void *)
+#endif
+
+/* Internal SLUB flags */
+#define __OBJECT_POISON 0x80000000      /* Poison object */
+
+static int kmem_size = sizeof(struct kmem_cache);
+
+#ifdef CONFIG_SMP
+static struct notifier_block slab_notifier;
+#endif
+
+static enum {
+        DOWN,           /* No slab functionality available */
+        PARTIAL,        /* kmem_cache_open() works but kmalloc does not */
+        UP,             /* Everything works */
+        SYSFS           /* Sysfs up */
+} slab_state = DOWN;
+
+/* A list of all slab caches on the system */
+static DECLARE_RWSEM(slub_lock);
+LIST_HEAD(slab_caches);
+
+#ifdef CONFIG_SYSFS
+static int sysfs_slab_add(struct kmem_cache *);
+static int sysfs_slab_alias(struct kmem_cache *, const char *);
+static void sysfs_slab_remove(struct kmem_cache *);
+#else
+static int sysfs_slab_add(struct kmem_cache *s) { return 0; }
+static int sysfs_slab_alias(struct kmem_cache *s, const char *p) { return 0; }
+static void sysfs_slab_remove(struct kmem_cache *s) {}
+#endif
+
+/********************************************************************
+ *                      Core slab cache functions
+ *******************************************************************/
+
+int slab_is_available(void)
+{
+        return slab_state >= UP;
+}
+
+static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
+{
+#ifdef CONFIG_NUMA
+        return s->node[node];
+#else
+        return &s->local_node;
+#endif
+}
+
+/*
+ * Object debugging
+ */
+static void print_section(char *text, u8 *addr, unsigned int length)
+{
+        int i, offset;
+        int newline = 1;
+        char ascii[17];
+
+        ascii[16] = 0;
+
+        for (i = 0; i < length; i++) {
+                if (newline) {
+                        printk(KERN_ERR "%10s 0x%p: ", text, addr + i);
+                        newline = 0;
+                }
+                printk(" %02x", addr[i]);
+                offset = i % 16;
+                ascii[offset] = isgraph(addr[i]) ? addr[i] : '.';
+                if (offset == 15) {
+                        printk(" %s\n",ascii);
+                        newline = 1;
+                }
+        }
+        if (!newline) {
+                i %= 16;
+                while (i < 16) {
+                        printk("   ");
+                        ascii[i] = ' ';
+                        i++;
+                }
+                printk(" %s\n", ascii);
+        }
+}
+
+/*
+ * Slow version of get and set free pointer.
+ *
+ * This requires touching the cache lines of kmem_cache.
+ * The offset can also be obtained from the page. In that
+ * case it is in the cacheline that we already need to touch.
+ */
+static void *get_freepointer(struct kmem_cache *s, void *object)
+{
+        return *(void **)(object + s->offset);
+}
+
+static void set_freepointer(struct kmem_cache *s, void *object, void *fp)
+{
+        *(void **)(object + s->offset) = fp;
+}
+
+/*
+ * Tracking user of a slab.
+ */
+struct track {
+        void *addr;             /* Called from address */
+        int cpu;                /* Was running on cpu */
+        int pid;                /* Pid context */
+        unsigned long when;     /* When did the operation occur */
+};
+
+enum track_item { TRACK_ALLOC, TRACK_FREE };
+
+static struct track *get_track(struct kmem_cache *s, void *object,
+        enum track_item alloc)
+{
+        struct track *p;
+
+        if (s->offset)
+                p = object + s->offset + sizeof(void *);
+        else
+                p = object + s->inuse;
+
+        return p + alloc;
+}
+
+static void set_track(struct kmem_cache *s, void *object,
+                                enum track_item alloc, void *addr)
+{
+        struct track *p;
+
+        if (s->offset)
+                p = object + s->offset + sizeof(void *);
+        else
+                p = object + s->inuse;
+
+        p += alloc;
+        if (addr) {
+                p->addr = addr;
+                p->cpu = smp_processor_id();
+                p->pid = current ? current->pid : -1;
+                p->when = jiffies;
+        } else
+                memset(p, 0, sizeof(struct track));
+}
+
+#define set_tracking(__s, __o, __a) set_track(__s, __o, __a, \
+                        __builtin_return_address(0))
+
+static void init_tracking(struct kmem_cache *s, void *object)
+{
+        if (s->flags & SLAB_STORE_USER) {
+                set_track(s, object, TRACK_FREE, NULL);
+                set_track(s, object, TRACK_ALLOC, NULL);
+        }
+}
+
+static void print_track(const char *s, struct track *t)
+{
+        if (!t->addr)
+                return;
+
+        printk(KERN_ERR "%s: ", s);
+        __print_symbol("%s", (unsigned long)t->addr);
+        printk(" jiffies_ago=%lu cpu=%u pid=%d\n", jiffies - t->when, t->cpu, t->pid);
+}
+
+static void print_trailer(struct kmem_cache *s, u8 *p)
+{
+        unsigned int off;       /* Offset of last byte */
+
+        if (s->flags & SLAB_RED_ZONE)
+                print_section("Redzone", p + s->objsize,
+                        s->inuse - s->objsize);
+
+        printk(KERN_ERR "FreePointer 0x%p -> 0x%p\n",
+                        p + s->offset,
+                        get_freepointer(s, p));
+
+        if (s->offset)
+                off = s->offset + sizeof(void *);
+        else
+                off = s->inuse;
+
+        if (s->flags & SLAB_STORE_USER) {
+                print_track("Last alloc", get_track(s, p, TRACK_ALLOC));
+                print_track("Last free ", get_track(s, p, TRACK_FREE));
+                off += 2 * sizeof(struct track);
+        }
+
+        if (off != s->size)
+                /* Beginning of the filler is the free pointer */
+                print_section("Filler", p + off, s->size - off);
+}
+
+static void object_err(struct kmem_cache *s, struct page *page,
+                        u8 *object, char *reason)
+{
+        u8 *addr = page_address(page);
+
+        printk(KERN_ERR "*** SLUB %s: %s@0x%p slab 0x%p\n",
+                        s->name, reason, object, page);
+        printk(KERN_ERR "    offset=%tu flags=0x%04lx inuse=%u freelist=0x%p\n",
+                object - addr, page->flags, page->inuse, page->freelist);
+        if (object > addr + 16)
+                print_section("Bytes b4", object - 16, 16);
+        print_section("Object", object, min(s->objsize, 128));
+        print_trailer(s, object);
+        dump_stack();
+}
+
+static void slab_err(struct kmem_cache *s, struct page *page, char *reason, ...)
+{
+        va_list args;
+        char buf[100];
+
+        va_start(args, reason);
+        vsnprintf(buf, sizeof(buf), reason, args);
+        va_end(args);
+        printk(KERN_ERR "*** SLUB %s: %s in slab @0x%p\n", s->name, buf,
+                page);
+        dump_stack();
+}
+
+static void init_object(struct kmem_cache *s, void *object, int active)
+{
+        u8 *p = object;
+
+        if (s->flags & __OBJECT_POISON) {
+                memset(p, POISON_FREE, s->objsize - 1);
+                p[s->objsize -1] = POISON_END;
+        }
+
+        if (s->flags & SLAB_RED_ZONE)
+                memset(p + s->objsize,
+                        active ? SLUB_RED_ACTIVE : SLUB_RED_INACTIVE,
+                        s->inuse - s->objsize);
+}
+
+static int check_bytes(u8 *start, unsigned int value, unsigned int bytes)
+{
+        while (bytes) {
+                if (*start != (u8)value)
+                        return 0;
+                start++;
+                bytes--;
+        }
+        return 1;
+}
+
+
+static int check_valid_pointer(struct kmem_cache *s, struct page *page,
+                                         void *object)
+{
+        void *base;
+
+        if (!object)
+                return 1;
+
+        base = page_address(page);
+        if (object < base || object >= base + s->objects * s->size ||
+                (object - base) % s->size) {
+                return 0;
+        }
+
+        return 1;
+}
+
+/*
+ * Object layout:
+ *
+ * object address
+ *      Bytes of the object to be managed.
+ *      If the freepointer may overlay the object then the free
+ *      pointer is the first word of the object.
+ *      Poisoning uses 0x6b (POISON_FREE) and the last byte is
+ *      0xa5 (POISON_END)
+ *
+ * object + s->objsize
+ *      Padding to reach word boundary. This is also used for Redzoning.
+ *      Padding is extended to word size if Redzoning is enabled
+ *      and objsize == inuse.
+ *      We fill with 0xbb (RED_INACTIVE) for inactive objects and with
+ *      0xcc (RED_ACTIVE) for objects in use.
+ *
+ * object + s->inuse
+ *      A. Free pointer (if we cannot overwrite object on free)
+ *      B. Tracking data for SLAB_STORE_USER
+ *      C. Padding to reach required alignment boundary
+ *              Padding is done using 0x5a (POISON_INUSE)
+ *
+ * object + s->size
+ *
+ * If slabcaches are merged then the objsize and inuse boundaries are to
+ * be ignored. And therefore no slab options that rely on these boundaries
+ * may be used with merged slabcaches.
+ */
+
+static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
+                                                void *from, void *to)
+{
+        printk(KERN_ERR "@@@ SLUB: %s Restoring %s (0x%x) from 0x%p-0x%p\n",
+                s->name, message, data, from, to - 1);
+        memset(from, data, to - from);
+}
+
+static int check_pad_bytes(struct kmem_cache *s, struct page *page, u8 *p)
+{
+        unsigned long off = s->inuse;   /* The end of info */
+
+        if (s->offset)
+                /* Freepointer is placed after the object. */
+                off += sizeof(void *);
+
+        if (s->flags & SLAB_STORE_USER)
+                /* We also have user information there */
+                off += 2 * sizeof(struct track);
+
+        if (s->size == off)
+                return 1;
+
+        if (check_bytes(p + off, POISON_INUSE, s->size - off))
+                return 1;
+
+        object_err(s, page, p, "Object padding check fails");
+
+        /*
+         * Restore padding
+         */
+        restore_bytes(s, "object padding", POISON_INUSE, p + off, p + s->size);
+        return 0;
+}
+
+static int slab_pad_check(struct kmem_cache *s, struct page *page)
+{
+        u8 *p;
+        int length, remainder;
+
+        if (!(s->flags & SLAB_POISON))
+                return 1;
+
+        p = page_address(page);
+        length = s->objects * s->size;
+        remainder = (PAGE_SIZE << s->order) - length;
+        if (!remainder)
+                return 1;
+
+        if (!check_bytes(p + length, POISON_INUSE, remainder)) {
+                printk(KERN_ERR "SLUB: %s slab 0x%p: Padding fails check\n",
+                        s->name, p);
+                dump_stack();
+                restore_bytes(s, "slab padding", POISON_INUSE, p + length,
+                        p + length + remainder);
+                return 0;
+        }
+        return 1;
+}
+
+static int check_object(struct kmem_cache *s, struct page *page,
+                                        void *object, int active)
+{
+        u8 *p = object;
+        u8 *endobject = object + s->objsize;
+
+        if (s->flags & SLAB_RED_ZONE) {
+                unsigned int red =
+                        active ? SLUB_RED_ACTIVE : SLUB_RED_INACTIVE;
+
+                if (!check_bytes(endobject, red, s->inuse - s->objsize)) {
+                        object_err(s, page, object,
+                        active ? "Redzone Active" : "Redzone Inactive");
+                        restore_bytes(s, "redzone", red,
+                                endobject, object + s->inuse);
+                        return 0;
+                }
+        } else {
+                if ((s->flags & SLAB_POISON) && s->objsize < s->inuse &&
+                        !check_bytes(endobject, POISON_INUSE,
+                                        s->inuse - s->objsize)) {
+                object_err(s, page, p, "Alignment padding check fails");
+                /*
+                 * Fix it so that there will not be another report.
+                 *
+                 * Hmmm... We may be corrupting an object that now expects
+                 * to be longer than allowed.
+                 */
+                restore_bytes(s, "alignment padding", POISON_INUSE,
+                        endobject, object + s->inuse);
+                }
+        }
+
+        if (s->flags & SLAB_POISON) {
+                if (!active && (s->flags & __OBJECT_POISON) &&
+                        (!check_bytes(p, POISON_FREE, s->objsize - 1) ||
+                                p[s->objsize - 1] != POISON_END)) {
+
+                        object_err(s, page, p, "Poison check failed");
+                        restore_bytes(s, "Poison", POISON_FREE,
+                                                p, p + s->objsize -1);
+                        restore_bytes(s, "Poison", POISON_END,
+                                        p + s->objsize - 1, p + s->objsize);
+                        return 0;
+                }
+                /*
+                 * check_pad_bytes cleans up on its own.
+                 */
+                check_pad_bytes(s, page, p);
+        }
+
+        if (!s->offset && active)
+                /*
+                 * Object and freepointer overlap. Cannot check
+                 * freepointer while object is allocated.
+                 */
+                return 1;
+
+        /* Check free pointer validity */
+        if (!check_valid_pointer(s, page, get_freepointer(s, p))) {
+                object_err(s, page, p, "Freepointer corrupt");
+                /*
+                 * No choice but to zap it and thus loose the remainder
+                 * of the free objects in this slab. May cause
+                 * another error because the object count maybe
+                 * wrong now.
+                 */
+                set_freepointer(s, p, NULL);
+                return 0;
+        }
+        return 1;
+}
+
+static int check_slab(struct kmem_cache *s, struct page *page)
+{
+        VM_BUG_ON(!irqs_disabled());
+
+        if (!PageSlab(page)) {
+                printk(KERN_ERR "SLUB: %s Not a valid slab page @0x%p "
+                        "flags=%lx mapping=0x%p count=%d \n",
+                        s->name, page, page->flags, page->mapping,
+                        page_count(page));
+                return 0;
+        }
+        if (page->offset * sizeof(void *) != s->offset) {
+                printk(KERN_ERR "SLUB: %s Corrupted offset %lu in slab @0x%p"
+                        " flags=0x%lx mapping=0x%p count=%d\n",
+                        s->name,
+                        (unsigned long)(page->offset * sizeof(void *)),
+                        page,
+                        page->flags,
+                        page->mapping,
+                        page_count(page));
+                dump_stack();
+                return 0;
+        }
+        if (page->inuse > s->objects) {
+                printk(KERN_ERR "SLUB: %s Inuse %u > max %u in slab "
+                        "page @0x%p flags=%lx mapping=0x%p count=%d\n",
+                        s->name, page->inuse, s->objects, page, page->flags,
+                        page->mapping, page_count(page));
+                dump_stack();
+                return 0;
+        }
+        /* Slab_pad_check fixes things up after itself */
+        slab_pad_check(s, page);
+        return 1;
+}
+
+/*
+ * Determine if a certain object on a page is on the freelist and
+ * therefore free. Must hold the slab lock for cpu slabs to
+ * guarantee that the chains are consistent.
+ */
+static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
+{
+        int nr = 0;
+        void *fp = page->freelist;
+        void *object = NULL;
+
+        while (fp && nr <= s->objects) {
+                if (fp == search)
+                        return 1;
+                if (!check_valid_pointer(s, page, fp)) {
+                        if (object) {
+                                object_err(s, page, object,
+                                        "Freechain corrupt");
+                                set_freepointer(s, object, NULL);
+                                break;
+                        } else {
+                                printk(KERN_ERR "SLUB: %s slab 0x%p "
+                                        "freepointer 0x%p corrupted.\n",
+                                        s->name, page, fp);
+                                dump_stack();
+                                page->freelist = NULL;
+                                page->inuse = s->objects;
+                                return 0;
+                        }
+                        break;
+                }
+                object = fp;
+                fp = get_freepointer(s, object);
+                nr++;
+        }
+
+        if (page->inuse != s->objects - nr) {
+                printk(KERN_ERR "slab %s: page 0x%p wrong object count."
+                        " counter is %d but counted were %d\n",
+                        s->name, page, page->inuse,
+                        s->objects - nr);
+                page->inuse = s->objects - nr;
+        }
+        return search == NULL;
+}
+
+static int alloc_object_checks(struct kmem_cache *s, struct page *page,
+                                                        void *object)
+{
+        if (!check_slab(s, page))
+                goto bad;
+
+        if (object && !on_freelist(s, page, object)) {
+                printk(KERN_ERR "SLUB: %s Object 0x%p@0x%p "
+                        "already allocated.\n",
+                        s->name, object, page);
+                goto dump;
+        }
+
+        if (!check_valid_pointer(s, page, object)) {
+                object_err(s, page, object, "Freelist Pointer check fails");
+                goto dump;
+        }
+
+        if (!object)
+                return 1;
+
+        if (!check_object(s, page, object, 0))
+                goto bad;
+        init_object(s, object, 1);
+
+        if (s->flags & SLAB_TRACE) {
+                printk(KERN_INFO "TRACE %s alloc 0x%p inuse=%d fp=0x%p\n",
+                        s->name, object, page->inuse,
+                        page->freelist);
+                dump_stack();
+        }
+        return 1;
+dump:
+        dump_stack();
+bad:
+        if (PageSlab(page)) {
+                /*
+                 * If this is a slab page then lets do the best we can
+                 * to avoid issues in the future. Marking all objects
+                 * as used avoids touching the remainder.
+                 */
+                printk(KERN_ERR "@@@ SLUB: %s slab 0x%p. Marking all objects used.\n",
+                        s->name, page);
+                page->inuse = s->objects;
+                page->freelist = NULL;
+                /* Fix up fields that may be corrupted */
+                page->offset = s->offset / sizeof(void *);
+        }
+        return 0;
+}
+
+static int free_object_checks(struct kmem_cache *s, struct page *page,
+                                                        void *object)
+{
+        if (!check_slab(s, page))
+                goto fail;
+
+        if (!check_valid_pointer(s, page, object)) {
+                printk(KERN_ERR "SLUB: %s slab 0x%p invalid "
+                        "object pointer 0x%p\n",
+                        s->name, page, object);
+                goto fail;
+        }
+
+        if (on_freelist(s, page, object)) {
+                printk(KERN_ERR "SLUB: %s slab 0x%p object "
+                        "0x%p already free.\n", s->name, page, object);
+                goto fail;
+        }
+
+        if (!check_object(s, page, object, 1))
+                return 0;
+
+        if (unlikely(s != page->slab)) {
+                if (!PageSlab(page))
+                        printk(KERN_ERR "slab_free %s size %d: attempt to"
+                                "free object(0x%p) outside of slab.\n",
+                                s->name, s->size, object);
+                else
+                if (!page->slab)
+                        printk(KERN_ERR
+                                "slab_free : no slab(NULL) for object 0x%p.\n",
+                                                object);
+                else
+                printk(KERN_ERR "slab_free %s(%d): object at 0x%p"
+                                " belongs to slab %s(%d)\n",
+                                s->name, s->size, object,
+                                page->slab->name, page->slab->size);
+                goto fail;
+        }
+        if (s->flags & SLAB_TRACE) {
+                printk(KERN_INFO "TRACE %s free 0x%p inuse=%d fp=0x%p\n",
+                        s->name, object, page->inuse,
+                        page->freelist);
+                print_section("Object", object, s->objsize);
+                dump_stack();
+        }
+        init_object(s, object, 0);
+        return 1;
+fail:
+        dump_stack();
+        printk(KERN_ERR "@@@ SLUB: %s slab 0x%p object at 0x%p not freed.\n",
+                s->name, page, object);
+        return 0;
+}
+
+/*
+ * Slab allocation and freeing
+ */
+static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
+{
+        struct page * page;
+        int pages = 1 << s->order;
+
+        if (s->order)
+                flags |= __GFP_COMP;
+
+        if (s->flags & SLAB_CACHE_DMA)
+                flags |= SLUB_DMA;
+
+        if (node == -1)
+                page = alloc_pages(flags, s->order);
+        else
+                page = alloc_pages_node(node, flags, s->order);
+
+        if (!page)
+                return NULL;
+
+        mod_zone_page_state(page_zone(page),
+                (s->flags & SLAB_RECLAIM_ACCOUNT) ?
+                NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
+                pages);
+
+        return page;
+}
+
+static void setup_object(struct kmem_cache *s, struct page *page,
+                                void *object)
+{
+        if (PageError(page)) {
+                init_object(s, object, 0);
+                init_tracking(s, object);
+        }
+
+        if (unlikely(s->ctor)) {
+                int mode = SLAB_CTOR_CONSTRUCTOR;
+
+                if (!(s->flags & __GFP_WAIT))
+                        mode |= SLAB_CTOR_ATOMIC;
+
+                s->ctor(object, s, mode);
+        }
+}
+
+static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node)
+{
+        struct page *page;
+        struct kmem_cache_node *n;
+        void *start;
+        void *end;
+        void *last;
+        void *p;
+
+        if (flags & __GFP_NO_GROW)
+                return NULL;
+
+        BUG_ON(flags & ~(GFP_DMA | GFP_LEVEL_MASK));
+
+        if (flags & __GFP_WAIT)
+                local_irq_enable();
+
+        page = allocate_slab(s, flags & GFP_LEVEL_MASK, node);
+        if (!page)
+                goto out;
+
+        n = get_node(s, page_to_nid(page));
+        if (n)
+                atomic_long_inc(&n->nr_slabs);
+        page->offset = s->offset / sizeof(void *);
+        page->slab = s;
+        page->flags |= 1 << PG_slab;
+        if (s->flags & (SLAB_DEBUG_FREE | SLAB_RED_ZONE | SLAB_POISON |
+                        SLAB_STORE_USER | SLAB_TRACE))
+                page->flags |= 1 << PG_error;
+
+        start = page_address(page);
+        end = start + s->objects * s->size;
+
+        if (unlikely(s->flags & SLAB_POISON))
+                memset(start, POISON_INUSE, PAGE_SIZE << s->order);
+
+        last = start;
+        for (p = start + s->size; p < end; p += s->size) {
+                setup_object(s, page, last);
+                set_freepointer(s, last, p);
+                last = p;
+        }
+        setup_object(s, page, last);
+        set_freepointer(s, last, NULL);
+
+        page->freelist = start;
+        page->inuse = 0;
+out:
+        if (flags & __GFP_WAIT)
+                local_irq_disable();
+        return page;
+}
+
+static void __free_slab(struct kmem_cache *s, struct page *page)
+{
+        int pages = 1 << s->order;
+
+        if (unlikely(PageError(page) || s->dtor)) {
+                void *start = page_address(page);
+                void *end = start + (pages << PAGE_SHIFT);
+                void *p;
+
+                slab_pad_check(s, page);
+                for (p = start; p <= end - s->size; p += s->size) {
+                        if (s->dtor)
+                                s->dtor(p, s, 0);
+                        check_object(s, page, p, 0);
+                }
+        }
+
+        mod_zone_page_state(page_zone(page),
+                (s->flags & SLAB_RECLAIM_ACCOUNT) ?
+                NR_SLAB_RECLAIMABLE : NR_SLAB_UNRECLAIMABLE,
+                - pages);
+
+        page->mapping = NULL;
+        __free_pages(page, s->order);
+}
+
+static void rcu_free_slab(struct rcu_head *h)
+{
+        struct page *page;
+
+        page = container_of((struct list_head *)h, struct page, lru);
+        __free_slab(page->slab, page);
+}
+
+static void free_slab(struct kmem_cache *s, struct page *page)
+{
+        if (unlikely(s->flags & SLAB_DESTROY_BY_RCU)) {
+                /*
+                 * RCU free overloads the RCU head over the LRU
+                 */
+                struct rcu_head *head = (void *)&page->lru;
+
+                call_rcu(head, rcu_free_slab);
+        } else
+                __free_slab(s, page);
+}
+
+static void discard_slab(struct kmem_cache *s, struct page *page)
+{
+        struct kmem_cache_node *n = get_node(s, page_to_nid(page));
+
+        atomic_long_dec(&n->nr_slabs);
+        reset_page_mapcount(page);
+        page->flags &= ~(1 << PG_slab | 1 << PG_error);
+        free_slab(s, page);
+}
+
+/*
+ * Per slab locking using the pagelock
+ */
+static __always_inline void slab_lock(struct page *page)
+{
+        bit_spin_lock(PG_locked, &page->flags);
+}
+
+static __always_inline void slab_unlock(struct page *page)
+{
+        bit_spin_unlock(PG_locked, &page->flags);
+}
+
+static __always_inline int slab_trylock(struct page *page)
+{
+        int rc = 1;
+
+        rc = bit_spin_trylock(PG_locked, &page->flags);
+        return rc;
+}
+
+/*
+ * Management of partially allocated slabs
+ */
+static void add_partial(struct kmem_cache *s, struct page *page)
+{
+        struct kmem_cache_node *n = get_node(s, page_to_nid(page));
+
+        spin_lock(&n->list_lock);
+        n->nr_partial++;
+        list_add(&page->lru, &n->partial);
+        spin_unlock(&n->list_lock);
+}
+
+static void remove_partial(struct kmem_cache *s,
+                                                struct page *page)
+{
+        struct kmem_cache_node *n = get_node(s, page_to_nid(page));
+
+        spin_lock(&n->list_lock);
+        list_del(&page->lru);
+        n->nr_partial--;
+        spin_unlock(&n->list_lock);
+}
+
+/*
+ * Lock page and remove it from the partial list
+ *
+ * Must hold list_lock
+ */
+static int lock_and_del_slab(struct kmem_cache_node *n, struct page *page)
+{
+        if (slab_trylock(page)) {
+                list_del(&page->lru);
+                n->nr_partial--;
+                return 1;
+        }
+        return 0;
+}
+
+/*
+ * Try to get a partial slab from a specific node
+ */
+static struct page *get_partial_node(struct kmem_cache_node *n)
+{
+        struct page *page;
+
+        /*
+         * Racy check. If we mistakenly see no partial slabs then we
+         * just allocate an empty slab. If we mistakenly try to get a
+         * partial slab then get_partials() will return NULL.
+         */
+        if (!n || !n->nr_partial)
+                return NULL;
+
+        spin_lock(&n->list_lock);
+        list_for_each_entry(page, &n->partial, lru)
+                if (lock_and_del_slab(n, page))
+                        goto out;
+        page = NULL;
+out:
+        spin_unlock(&n->list_lock);
+        return page;
+}
+
+/*
+ * Get a page from somewhere. Search in increasing NUMA
+ * distances.
+ */
+static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags)
+{
+#ifdef CONFIG_NUMA
+        struct zonelist *zonelist;
+        struct zone **z;
+        struct page *page;
+
+        /*
+         * The defrag ratio allows to configure the tradeoffs between
+         * inter node defragmentation and node local allocations.
+         * A lower defrag_ratio increases the tendency to do local
+         * allocations instead of scanning throught the partial
+         * lists on other nodes.
+         *
+         * If defrag_ratio is set to 0 then kmalloc() always
+         * returns node local objects. If its higher then kmalloc()
+         * may return off node objects in order to avoid fragmentation.
+         *
+         * A higher ratio means slabs may be taken from other nodes
+         * thus reducing the number of partial slabs on those nodes.
+         *
+         * If /sys/slab/xx/defrag_ratio is set to 100 (which makes
+         * defrag_ratio = 1000) then every (well almost) allocation
+         * will first attempt to defrag slab caches on other nodes. This
+         * means scanning over all nodes to look for partial slabs which
+         * may be a bit expensive to do on every slab allocation.
+         */
+        if (!s->defrag_ratio || get_cycles() % 1024 > s->defrag_ratio)
+                return NULL;
+
+        zonelist = &NODE_DATA(slab_node(current->mempolicy))
+                                        ->node_zonelists[gfp_zone(flags)];
+        for (z = zonelist->zones; *z; z++) {
+                struct kmem_cache_node *n;
+
+                n = get_node(s, zone_to_nid(*z));
+
+                if (n && cpuset_zone_allowed_hardwall(*z, flags) &&
+                                n->nr_partial > 2) {
+                        page = get_partial_node(n);
+                        if (page)
+                                return page;
+                }
+        }
+#endif
+        return NULL;
+}
+
+/*
+ * Get a partial page, lock it and return it.
+ */
+static struct page *get_partial(struct kmem_cache *s, gfp_t flags, int node)
+{
+        struct page *page;
+        int searchnode = (node == -1) ? numa_node_id() : node;
+
+        page = get_partial_node(get_node(s, searchnode));
+        if (page || (flags & __GFP_THISNODE))
+                return page;
+
+        return get_any_partial(s, flags);
+}
+
+/*
+ * Move a page back to the lists.
+ *
+ * Must be called with the slab lock held.
+ *
+ * On exit the slab lock will have been dropped.
+ */
+static void putback_slab(struct kmem_cache *s, struct page *page)
+{
+        if (page->inuse) {
+                if (page->freelist)
+                        add_partial(s, page);
+                slab_unlock(page);
+        } else {
+                slab_unlock(page);
+                discard_slab(s, page);
+        }
+}
+
+/*
+ * Remove the cpu slab
+ */
+static void deactivate_slab(struct kmem_cache *s, struct page *page, int cpu)
+{
+        s->cpu_slab[cpu] = NULL;
+        ClearPageActive(page);
+
+        putback_slab(s, page);
+}
+
+static void flush_slab(struct kmem_cache *s, struct page *page, int cpu)
+{
+        slab_lock(page);
+        deactivate_slab(s, page, cpu);
+}
+
+/*
+ * Flush cpu slab.
+ * Called from IPI handler with interrupts disabled.
+ */
+static void __flush_cpu_slab(struct kmem_cache *s, int cpu)
+{
+        struct page *page = s->cpu_slab[cpu];
+
+        if (likely(page))
+                flush_slab(s, page, cpu);
+}
+
+static void flush_cpu_slab(void *d)
+{
+        struct kmem_cache *s = d;
+        int cpu = smp_processor_id();
+
+        __flush_cpu_slab(s, cpu);
+}
+
+static void flush_all(struct kmem_cache *s)
+{
+#ifdef CONFIG_SMP
+        on_each_cpu(flush_cpu_slab, s, 1, 1);
+#else
+        unsigned long flags;
+
+        local_irq_save(flags);
+        flush_cpu_slab(s);
+        local_irq_restore(flags);
+#endif
+}
+
+/*
+ * slab_alloc is optimized to only modify two cachelines on the fast path
+ * (aside from the stack):
+ *
+ * 1. The page struct
+ * 2. The first cacheline of the object to be allocated.
+ *
+ * The only cache lines that are read (apart from code) is the
+ * per cpu array in the kmem_cache struct.
+ *
+ * Fastpath is not possible if we need to get a new slab or have
+ * debugging enabled (which means all slabs are marked with PageError)
+ */
+static __always_inline void *slab_alloc(struct kmem_cache *s,
+                                        gfp_t gfpflags, int node)
+{
+        struct page *page;
+        void **object;
+        unsigned long flags;
+        int cpu;
+
+        local_irq_save(flags);
+        cpu = smp_processor_id();
+        page = s->cpu_slab[cpu];
+        if (!page)
+                goto new_slab;
+
+        slab_lock(page);
+        if (unlikely(node != -1 && page_to_nid(page) != node))
+                goto another_slab;
+redo:
+        object = page->freelist;
+        if (unlikely(!object))
+                goto another_slab;
+        if (unlikely(PageError(page)))
+                goto debug;
+
+have_object:
+        page->inuse++;
+        page->freelist = object[page->offset];
+        slab_unlock(page);
+        local_irq_restore(flags);
+        return object;
+
+another_slab:
+        deactivate_slab(s, page, cpu);
+
+new_slab:
+        page = get_partial(s, gfpflags, node);
+        if (likely(page)) {
+have_slab:
+                s->cpu_slab[cpu] = page;
+                SetPageActive(page);
+                goto redo;
+        }
+
+        page = new_slab(s, gfpflags, node);
+        if (page) {
+                cpu = smp_processor_id();
+                if (s->cpu_slab[cpu]) {
+                        /*
+                         * Someone else populated the cpu_slab while we enabled
+                         * interrupts, or we have got scheduled on another cpu.
+                         * The page may not be on the requested node.
+                         */
+                        if (node == -1 ||
+                                page_to_nid(s->cpu_slab[cpu]) == node) {
+                                /*
+                                 * Current cpuslab is acceptable and we
+                                 * want the current one since its cache hot
+                                 */
+                                discard_slab(s, page);
+                                page = s->cpu_slab[cpu];
+                                slab_lock(page);
+                                goto redo;
+                        }
+                        /* Dump the current slab */
+                        flush_slab(s, s->cpu_slab[cpu], cpu);
+                }
+                slab_lock(page);
+                goto have_slab;
+        }
+        local_irq_restore(flags);
+        return NULL;
+debug:
+        if (!alloc_object_checks(s, page, object))
+                goto another_slab;
+        if (s->flags & SLAB_STORE_USER)
+                set_tracking(s, object, TRACK_ALLOC);
+        goto have_object;
+}
+
+void *kmem_cache_alloc(struct kmem_cache *s, gfp_t gfpflags)
+{
+        return slab_alloc(s, gfpflags, -1);
+}
+EXPORT_SYMBOL(kmem_cache_alloc);
+
+#ifdef CONFIG_NUMA
+void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t gfpflags, int node)
+{
+        return slab_alloc(s, gfpflags, node);
+}
+EXPORT_SYMBOL(kmem_cache_alloc_node);
+#endif
+
+/*
+ * The fastpath only writes the cacheline of the page struct and the first
+ * cacheline of the object.
+ *
+ * No special cachelines need to be read
+ */
+static void slab_free(struct kmem_cache *s, struct page *page, void *x)
+{
+        void *prior;
+        void **object = (void *)x;
+        unsigned long flags;
+
+        local_irq_save(flags);
+        slab_lock(page);
+
+        if (unlikely(PageError(page)))
+                goto debug;
+checks_ok:
+        prior = object[page->offset] = page->freelist;
+        page->freelist = object;
+        page->inuse--;
+
+        if (unlikely(PageActive(page)))
+                /*
+                 * Cpu slabs are never on partial lists and are
+                 * never freed.
+                 */
+                goto out_unlock;
+
+        if (unlikely(!page->inuse))
+                goto slab_empty;
+
+        /*
+         * Objects left in the slab. If it
+         * was not on the partial list before
+         * then add it.
+         */
+        if (unlikely(!prior))
+                add_partial(s, page);
+
+out_unlock:
+        slab_unlock(page);
+        local_irq_restore(flags);
+        return;
+
+slab_empty:
+        if (prior)
+                /*
+                 * Partially used slab that is on the partial list.
+                 */
+                remove_partial(s, page);
+
+        slab_unlock(page);
+        discard_slab(s, page);
+        local_irq_restore(flags);
+        return;
+
+debug:
+        if (free_object_checks(s, page, x))
+                goto checks_ok;
+        goto out_unlock;
+}
+
+void kmem_cache_free(struct kmem_cache *s, void *x)
+{
+        struct page * page;
+
+        page = virt_to_page(x);
+
+        if (unlikely(PageCompound(page)))
+                page = page->first_page;
+
+
+        if (unlikely(PageError(page) && (s->flags & SLAB_STORE_USER)))
+                set_tracking(s, x, TRACK_FREE);
+        slab_free(s, page, x);
+}
+EXPORT_SYMBOL(kmem_cache_free);
+
+/* Figure out on which slab object the object resides */
+static struct page *get_object_page(const void *x)
+{
+        struct page *page = virt_to_page(x);
+
+        if (unlikely(PageCompound(page)))
+                page = page->first_page;
+
+        if (!PageSlab(page))
+                return NULL;
+
+        return page;
+}
+
+/*
+ * kmem_cache_open produces objects aligned at "size" and the first object
+ * is placed at offset 0 in the slab (We have no metainformation on the
+ * slab, all slabs are in essence "off slab").
+ *
+ * In order to get the desired alignment one just needs to align the
+ * size.
+ *
+ * Notice that the allocation order determines the sizes of the per cpu
+ * caches. Each processor has always one slab available for allocations.
+ * Increasing the allocation order reduces the number of times that slabs
+ * must be moved on and off the partial lists and therefore may influence
+ * locking overhead.
+ *
+ * The offset is used to relocate the free list link in each object. It is
+ * therefore possible to move the free list link behind the object. This
+ * is necessary for RCU to work properly and also useful for debugging.
+ */
+
+/*
+ * Mininum / Maximum order of slab pages. This influences locking overhead
+ * and slab fragmentation. A higher order reduces the number of partial slabs
+ * and increases the number of allocations possible without having to
+ * take the list_lock.
+ */
+static int slub_min_order;
+static int slub_max_order = DEFAULT_MAX_ORDER;
+
+/*
+ * Minimum number of objects per slab. This is necessary in order to
+ * reduce locking overhead. Similar to the queue size in SLAB.
+ */
+static int slub_min_objects = DEFAULT_MIN_OBJECTS;
+
+/*
+ * Merge control. If this is set then no merging of slab caches will occur.
+ */
+static int slub_nomerge;
+
+/*
+ * Debug settings:
+ */
+static int slub_debug;
+
+static char *slub_debug_slabs;
+
+/*
+ * Calculate the order of allocation given an slab object size.
+ *
+ * The order of allocation has significant impact on other elements
+ * of the system. Generally order 0 allocations should be preferred
+ * since they do not cause fragmentation in the page allocator. Larger
+ * objects may have problems with order 0 because there may be too much
+ * space left unused in a slab. We go to a higher order if more than 1/8th
+ * of the slab would be wasted.
+ *
+ * In order to reach satisfactory performance we must ensure that
+ * a minimum number of objects is in one slab. Otherwise we may
+ * generate too much activity on the partial lists. This is less a
+ * concern for large slabs though. slub_max_order specifies the order
+ * where we begin to stop considering the number of objects in a slab.
+ *
+ * Higher order allocations also allow the placement of more objects
+ * in a slab and thereby reduce object handling overhead. If the user
+ * has requested a higher mininum order then we start with that one
+ * instead of zero.
+ */
+static int calculate_order(int size)
+{
+        int order;
+        int rem;
+
+        for (order = max(slub_min_order, fls(size - 1) - PAGE_SHIFT);
+                        order < MAX_ORDER; order++) {
+                unsigned long slab_size = PAGE_SIZE << order;
+
+                if (slub_max_order > order &&
+                                slab_size < slub_min_objects * size)
+                        continue;
+
+                if (slab_size < size)
+                        continue;
+
+                rem = slab_size % size;
+
+                if (rem <= (PAGE_SIZE << order) / 8)
+                        break;
+
+        }
+        if (order >= MAX_ORDER)
+                return -E2BIG;
+        return order;
+}
+
+/*
+ * Function to figure out which alignment to use from the
+ * various ways of specifying it.
+ */
+static unsigned long calculate_alignment(unsigned long flags,
+                unsigned long align, unsigned long size)
+{
+        /*
+         * If the user wants hardware cache aligned objects then
+         * follow that suggestion if the object is sufficiently
+         * large.
+         *
+         * The hardware cache alignment cannot override the
+         * specified alignment though. If that is greater
+         * then use it.
+         */
+        if ((flags & (SLAB_MUST_HWCACHE_ALIGN | SLAB_HWCACHE_ALIGN)) &&
+                        size > L1_CACHE_BYTES / 2)
+                return max_t(unsigned long, align, L1_CACHE_BYTES);
+
+        if (align < ARCH_SLAB_MINALIGN)
+                return ARCH_SLAB_MINALIGN;
+
+        return ALIGN(align, sizeof(void *));
+}
+
+static void init_kmem_cache_node(struct kmem_cache_node *n)
+{
+        n->nr_partial = 0;
+        atomic_long_set(&n->nr_slabs, 0);
+        spin_lock_init(&n->list_lock);
+        INIT_LIST_HEAD(&n->partial);
+}
+
+#ifdef CONFIG_NUMA
+/*
+ * No kmalloc_node yet so do it by hand. We know that this is the first
+ * slab on the node for this slabcache. There are no concurrent accesses
+ * possible.
+ *
+ * Note that this function only works on the kmalloc_node_cache
+ * when allocating for the kmalloc_node_cache.
+ */
+static struct kmem_cache_node * __init early_kmem_cache_node_alloc(gfp_t gfpflags,
+                                                                int node)
+{
+        struct page *page;
+        struct kmem_cache_node *n;
+
+        BUG_ON(kmalloc_caches->size < sizeof(struct kmem_cache_node));
+
+        page = new_slab(kmalloc_caches, gfpflags | GFP_THISNODE, node);
+        /* new_slab() disables interupts */
+        local_irq_enable();
+
+        BUG_ON(!page);
+        n = page->freelist;
+        BUG_ON(!n);
+        page->freelist = get_freepointer(kmalloc_caches, n);
+        page->inuse++;
+        kmalloc_caches->node[node] = n;
+        init_object(kmalloc_caches, n, 1);
+        init_kmem_cache_node(n);
+        atomic_long_inc(&n->nr_slabs);
+        add_partial(kmalloc_caches, page);
+        return n;
+}
+
+static void free_kmem_cache_nodes(struct kmem_cache *s)
+{
+        int node;
+
+        for_each_online_node(node) {
+                struct kmem_cache_node *n = s->node[node];
+                if (n && n != &s->local_node)
+                        kmem_cache_free(kmalloc_caches, n);
+                s->node[node] = NULL;
+        }
+}
+
+static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
+{
+        int node;
+        int local_node;
+
+        if (slab_state >= UP)
+                local_node = page_to_nid(virt_to_page(s));
+        else
+                local_node = 0;
+
+        for_each_online_node(node) {
+                struct kmem_cache_node *n;
+
+                if (local_node == node)
+                        n = &s->local_node;
+                else {
+                        if (slab_state == DOWN) {
+                                n = early_kmem_cache_node_alloc(gfpflags,
+                                                                node);
+                                continue;
+                        }
+                        n = kmem_cache_alloc_node(kmalloc_caches,
+                                                        gfpflags, node);
+
+                        if (!n) {
+                                free_kmem_cache_nodes(s);
+                                return 0;
+                        }
+
+                }
+                s->node[node] = n;
+                init_kmem_cache_node(n);
+        }
+        return 1;
+}
+#else
+static void free_kmem_cache_nodes(struct kmem_cache *s)
+{
+}
+
+static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
+{
+        init_kmem_cache_node(&s->local_node);
+        return 1;
+}
+#endif
+
+/*
+ * calculate_sizes() determines the order and the distribution of data within
+ * a slab object.
+ */
+static int calculate_sizes(struct kmem_cache *s)
+{
+        unsigned long flags = s->flags;
+        unsigned long size = s->objsize;
+        unsigned long align = s->align;
+
+        /*
+         * Determine if we can poison the object itself. If the user of
+         * the slab may touch the object after free or before allocation
+         * then we should never poison the object itself.
+         */
+        if ((flags & SLAB_POISON) && !(flags & SLAB_DESTROY_BY_RCU) &&
+                        !s->ctor && !s->dtor)
+                s->flags |= __OBJECT_POISON;
+        else
+                s->flags &= ~__OBJECT_POISON;
+
+        /*
+         * Round up object size to the next word boundary. We can only
+         * place the free pointer at word boundaries and this determines
+         * the possible location of the free pointer.
+         */
+        size = ALIGN(size, sizeof(void *));
+
+        /*
+         * If we are redzoning then check if there is some space between the
+         * end of the object and the free pointer. If not then add an
+         * additional word, so that we can establish a redzone between
+         * the object and the freepointer to be able to check for overwrites.
+         */
+        if ((flags & SLAB_RED_ZONE) && size == s->objsize)
+                size += sizeof(void *);
+
+        /*
+         * With that we have determined how much of the slab is in actual
+         * use by the object. This is the potential offset to the free
+         * pointer.
+         */
+        s->inuse = size;
+
+        if (((flags & (SLAB_DESTROY_BY_RCU | SLAB_POISON)) ||
+                s->ctor || s->dtor)) {
+                /*
+                 * Relocate free pointer after the object if it is not
+                 * permitted to overwrite the first word of the object on
+                 * kmem_cache_free.
+                 *
+                 * This is the case if we do RCU, have a constructor or
+                 * destructor or are poisoning the objects.
+                 */
+                s->offset = size;
+                size += sizeof(void *);
+        }
+
+        if (flags & SLAB_STORE_USER)
+                /*
+                 * Need to store information about allocs and frees after
+                 * the object.
+                 */
+                size += 2 * sizeof(struct track);
+
+        if (flags & DEBUG_DEFAULT_FLAGS)
+                /*
+                 * Add some empty padding so that we can catch
+                 * overwrites from earlier objects rather than let
+                 * tracking information or the free pointer be
+                 * corrupted if an user writes before the start
+                 * of the object.
+                 */
+                size += sizeof(void *);
+        /*
+         * Determine the alignment based on various parameters that the
+         * user specified (this is unecessarily complex due to the attempt
+         * to be compatible with SLAB. Should be cleaned up some day).
+         */
+        align = calculate_alignment(flags, align, s->objsize);
+
+        /*
+         * SLUB stores one object immediately after another beginning from
+         * offset 0. In order to align the objects we have to simply size
+         * each object to conform to the alignment.
+         */
+        size = ALIGN(size, align);
+        s->size = size;
+
+        s->order = calculate_order(size);
+        if (s->order < 0)
+                return 0;
+
+        /*
+         * Determine the number of objects per slab
+         */
+        s->objects = (PAGE_SIZE << s->order) / size;
+
+        /*
+         * Verify that the number of objects is within permitted limits.
+         * The page->inuse field is only 16 bit wide! So we cannot have
+         * more than 64k objects per slab.
+         */
+        if (!s->objects || s->objects > 65535)
+                return 0;
+        return 1;
+
+}
+
+static int __init finish_bootstrap(void)
+{
+        struct list_head *h;
+        int err;
+
+        slab_state = SYSFS;
+
+        list_for_each(h, &slab_caches) {
+                struct kmem_cache *s =
+                        container_of(h, struct kmem_cache, list);
+
+                err = sysfs_slab_add(s);
+                BUG_ON(err);
+        }
+        return 0;
+}
+
+static int kmem_cache_open(struct kmem_cache *s, gfp_t gfpflags,
+                const char *name, size_t size,
+                size_t align, unsigned long flags,
+                void (*ctor)(void *, struct kmem_cache *, unsigned long),
+                void (*dtor)(void *, struct kmem_cache *, unsigned long))
+{
+        memset(s, 0, kmem_size);
+        s->name = name;
+        s->ctor = ctor;
+        s->dtor = dtor;
+        s->objsize = size;
+        s->flags = flags;
+        s->align = align;
+
+        BUG_ON(flags & SLUB_UNIMPLEMENTED);
+
+        /*
+         * The page->offset field is only 16 bit wide. This is an offset
+         * in units of words from the beginning of an object. If the slab
+         * size is bigger then we cannot move the free pointer behind the
+         * object anymore.
+         *
+         * On 32 bit platforms the limit is 256k. On 64bit platforms
+         * the limit is 512k.
+         *
+         * Debugging or ctor/dtors may create a need to move the free
+         * pointer. Fail if this happens.
+         */
+        if (s->size >= 65535 * sizeof(void *)) {
+                BUG_ON(flags & (SLAB_RED_ZONE | SLAB_POISON |
+                                SLAB_STORE_USER | SLAB_DESTROY_BY_RCU));
+                BUG_ON(ctor || dtor);
+        }
+        else
+                /*
+                 * Enable debugging if selected on the kernel commandline.
+                 */
+                if (slub_debug && (!slub_debug_slabs ||
+                    strncmp(slub_debug_slabs, name,
+                        strlen(slub_debug_slabs)) == 0))
+                                s->flags |= slub_debug;
+
+        if (!calculate_sizes(s))
+                goto error;
+
+        s->refcount = 1;
+#ifdef CONFIG_NUMA
+        s->defrag_ratio = 100;
+#endif
+
+        if (init_kmem_cache_nodes(s, gfpflags & ~SLUB_DMA))
+                return 1;
+error:
+        if (flags & SLAB_PANIC)
+                panic("Cannot create slab %s size=%lu realsize=%u "
+                        "order=%u offset=%u flags=%lx\n",
+                        s->name, (unsigned long)size, s->size, s->order,
+                        s->offset, flags);
+        return 0;
+}
+EXPORT_SYMBOL(kmem_cache_open);
+
+/*
+ * Check if a given pointer is valid
+ */
+int kmem_ptr_validate(struct kmem_cache *s, const void *object)
+{
+        struct page * page;
+        void *addr;
+
+        page = get_object_page(object);
+
+        if (!page || s != page->slab)
+                /* No slab or wrong slab */
+                return 0;
+
+        addr = page_address(page);
+        if (object < addr || object >= addr + s->objects * s->size)
+                /* Out of bounds */
+                return 0;
+
+        if ((object - addr) % s->size)
+                /* Improperly aligned */
+                return 0;
+
+        /*
+         * We could also check if the object is on the slabs freelist.
+         * But this would be too expensive and it seems that the main
+         * purpose of kmem_ptr_valid is to check if the object belongs
+         * to a certain slab.
+         */
+        return 1;
+}
+EXPORT_SYMBOL(kmem_ptr_validate);
+
+/*
+ * Determine the size of a slab object
+ */
+unsigned int kmem_cache_size(struct kmem_cache *s)
+{
+        return s->objsize;
+}
+EXPORT_SYMBOL(kmem_cache_size);
+
+const char *kmem_cache_name(struct kmem_cache *s)
+{
+        return s->name;
+}
+EXPORT_SYMBOL(kmem_cache_name);
+
+/*
+ * Attempt to free all slabs on a node
+ */
+static int free_list(struct kmem_cache *s, struct kmem_cache_node *n,
+                        struct list_head *list)
+{
+        int slabs_inuse = 0;
+        unsigned long flags;
+        struct page *page, *h;
+
+        spin_lock_irqsave(&n->list_lock, flags);
+        list_for_each_entry_safe(page, h, list, lru)
+                if (!page->inuse) {
+                        list_del(&page->lru);
+                        discard_slab(s, page);
+                } else
+                        slabs_inuse++;
+        spin_unlock_irqrestore(&n->list_lock, flags);
+        return slabs_inuse;
+}
+
+/*
+ * Release all resources used by slab cache
+ */
+static int kmem_cache_close(struct kmem_cache *s)
+{
+        int node;
+
+        flush_all(s);
+
+        /* Attempt to free all objects */
+        for_each_online_node(node) {
+                struct kmem_cache_node *n = get_node(s, node);
+
+                free_list(s, n, &n->partial);
+                if (atomic_long_read(&n->nr_slabs))
+                        return 1;
+        }
+        free_kmem_cache_nodes(s);
+        return 0;
+}
+
+/*
+ * Close a cache and release the kmem_cache structure
+ * (must be used for caches created using kmem_cache_create)
+ */
+void kmem_cache_destroy(struct kmem_cache *s)
+{
+        down_write(&slub_lock);
+        s->refcount--;
+        if (!s->refcount) {
+                list_del(&s->list);
+                if (kmem_cache_close(s))
+                        WARN_ON(1);
+                sysfs_slab_remove(s);
+                kfree(s);
+        }
+        up_write(&slub_lock);
+}
+EXPORT_SYMBOL(kmem_cache_destroy);
+
+/********************************************************************
+ *              Kmalloc subsystem
+ *******************************************************************/
+
+struct kmem_cache kmalloc_caches[KMALLOC_SHIFT_HIGH + 1] __cacheline_aligned;
+EXPORT_SYMBOL(kmalloc_caches);
+
+#ifdef CONFIG_ZONE_DMA
+static struct kmem_cache *kmalloc_caches_dma[KMALLOC_SHIFT_HIGH + 1];
+#endif
+
+static int __init setup_slub_min_order(char *str)
+{
+        get_option (&str, &slub_min_order);
+
+        return 1;
+}
+
+__setup("slub_min_order=", setup_slub_min_order);
+
+static int __init setup_slub_max_order(char *str)
+{
+        get_option (&str, &slub_max_order);
+
+        return 1;
+}
+
+__setup("slub_max_order=", setup_slub_max_order);
+
+static int __init setup_slub_min_objects(char *str)
+{
+        get_option (&str, &slub_min_objects);
+
+        return 1;
+}
+
+__setup("slub_min_objects=", setup_slub_min_objects);
+
+static int __init setup_slub_nomerge(char *str)
+{
+        slub_nomerge = 1;
+        return 1;
+}
+
+__setup("slub_nomerge", setup_slub_nomerge);
+
+static int __init setup_slub_debug(char *str)
+{
+        if (!str || *str != '=')
+                slub_debug = DEBUG_DEFAULT_FLAGS;
+        else {
+                str++;
+                if (*str == 0 || *str == ',')
+                        slub_debug = DEBUG_DEFAULT_FLAGS;
+                else
+                for( ;*str && *str != ','; str++)
+                        switch (*str) {
+                        case 'f' : case 'F' :
+                                slub_debug |= SLAB_DEBUG_FREE;
+                                break;
+                        case 'z' : case 'Z' :
+                                slub_debug |= SLAB_RED_ZONE;
+                                break;
+                        case 'p' : case 'P' :
+                                slub_debug |= SLAB_POISON;
+                                break;
+                        case 'u' : case 'U' :
+                                slub_debug |= SLAB_STORE_USER;
+                                break;
+                        case 't' : case 'T' :
+                                slub_debug |= SLAB_TRACE;
+                                break;
+                        default:
+                                printk(KERN_ERR "slub_debug option '%c' "
+                                        "unknown. skipped\n",*str);
+                        }
+        }
+
+        if (*str == ',')
+                slub_debug_slabs = str + 1;
+        return 1;
+}
+
+__setup("slub_debug", setup_slub_debug);
+
+static struct kmem_cache *create_kmalloc_cache(struct kmem_cache *s,
+                const char *name, int size, gfp_t gfp_flags)
+{
+        unsigned int flags = 0;
+
+        if (gfp_flags & SLUB_DMA)
+                flags = SLAB_CACHE_DMA;
+
+        down_write(&slub_lock);
+        if (!kmem_cache_open(s, gfp_flags, name, size, ARCH_KMALLOC_MINALIGN,
+                        flags, NULL, NULL))
+                goto panic;
+
+        list_add(&s->list, &slab_caches);
+        up_write(&slub_lock);
+        if (sysfs_slab_add(s))
+                goto panic;
+        return s;
+
+panic:
+        panic("Creation of kmalloc slab %s size=%d failed.\n", name, size);
+}
+
+static struct kmem_cache *get_slab(size_t size, gfp_t flags)
+{
+        int index = kmalloc_index(size);
+
+        if (!size)
+                return NULL;
+
+        /* Allocation too large? */
+        BUG_ON(index < 0);
+
+#ifdef CONFIG_ZONE_DMA
+        if ((flags & SLUB_DMA)) {
+                struct kmem_cache *s;
+                struct kmem_cache *x;
+                char *text;
+                size_t realsize;
+
+                s = kmalloc_caches_dma[index];
+                if (s)
+                        return s;
+
+                /* Dynamically create dma cache */
+                x = kmalloc(kmem_size, flags & ~SLUB_DMA);
+                if (!x)
+                        panic("Unable to allocate memory for dma cache\n");
+
+                if (index <= KMALLOC_SHIFT_HIGH)
+                        realsize = 1 << index;
+                else {
+                        if (index == 1)
+                                realsize = 96;
+                        else
+                                realsize = 192;
+                }
+
+                text = kasprintf(flags & ~SLUB_DMA, "kmalloc_dma-%d",
+                                (unsigned int)realsize);
+                s = create_kmalloc_cache(x, text, realsize, flags);
+                kmalloc_caches_dma[index] = s;
+                return s;
+        }
+#endif
+        return &kmalloc_caches[index];
+}
+
+void *__kmalloc(size_t size, gfp_t flags)
+{
+        struct kmem_cache *s = get_slab(size, flags);
+
+        if (s)
+                return kmem_cache_alloc(s, flags);
+        return NULL;
+}
+EXPORT_SYMBOL(__kmalloc);
+
+#ifdef CONFIG_NUMA
+void *__kmalloc_node(size_t size, gfp_t flags, int node)
+{
+        struct kmem_cache *s = get_slab(size, flags);
+
+        if (s)
+                return kmem_cache_alloc_node(s, flags, node);
+        return NULL;
+}
+EXPORT_SYMBOL(__kmalloc_node);
+#endif
+
+size_t ksize(const void *object)
+{
+        struct page *page = get_object_page(object);
+        struct kmem_cache *s;
+
+        BUG_ON(!page);
+        s = page->slab;
+        BUG_ON(!s);
+
+        /*
+         * Debugging requires use of the padding between object
+         * and whatever may come after it.
+         */
+        if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
+                return s->objsize;
+
+        /*
+         * If we have the need to store the freelist pointer
+         * back there or track user information then we can
+         * only use the space before that information.
+         */
+        if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER))
+                return s->inuse;
+
+        /*
+         * Else we can use all the padding etc for the allocation
+         */
+        return s->size;
+}
+EXPORT_SYMBOL(ksize);
+
+void kfree(const void *x)
+{
+        struct kmem_cache *s;
+        struct page *page;
+
+        if (!x)
+                return;
+
+        page = virt_to_page(x);
+
+        if (unlikely(PageCompound(page)))
+                page = page->first_page;
+
+        s = page->slab;
+
+        if (unlikely(PageError(page) && (s->flags & SLAB_STORE_USER)))
+                set_tracking(s, (void *)x, TRACK_FREE);
+        slab_free(s, page, (void *)x);
+}
+EXPORT_SYMBOL(kfree);
+
+/**
+ * krealloc - reallocate memory. The contents will remain unchanged.
+ *
+ * @p: object to reallocate memory for.
+ * @new_size: how many bytes of memory are required.
+ * @flags: the type of memory to allocate.
+ *
+ * The contents of the object pointed to are preserved up to the
+ * lesser of the new and old sizes.  If @p is %NULL, krealloc()
+ * behaves exactly like kmalloc().  If @size is 0 and @p is not a
+ * %NULL pointer, the object pointed to is freed.
+ */
+void *krealloc(const void *p, size_t new_size, gfp_t flags)
+{
+        struct kmem_cache *new_cache;
+        void *ret;
+        struct page *page;
+
+        if (unlikely(!p))
+                return kmalloc(new_size, flags);
+
+        if (unlikely(!new_size)) {
+                kfree(p);
+                return NULL;
+        }
+
+        page = virt_to_page(p);
+
+        if (unlikely(PageCompound(page)))
+                page = page->first_page;
+
+        new_cache = get_slab(new_size, flags);
+
+        /*
+         * If new size fits in the current cache, bail out.
+         */
+        if (likely(page->slab == new_cache))
+                return (void *)p;
+
+        ret = kmalloc(new_size, flags);
+        if (ret) {
+                memcpy(ret, p, min(new_size, ksize(p)));
+                kfree(p);
+        }
+        return ret;
+}
+EXPORT_SYMBOL(krealloc);
+
+/********************************************************************
+ *                      Basic setup of slabs
+ *******************************************************************/
+
+void __init kmem_cache_init(void)
+{
+        int i;
+
+#ifdef CONFIG_NUMA
+        /*
+         * Must first have the slab cache available for the allocations of the
+         * struct kmalloc_cache_node's. There is special bootstrap code in
+         * kmem_cache_open for slab_state == DOWN.
+         */
+        create_kmalloc_cache(&kmalloc_caches[0], "kmem_cache_node",
+                sizeof(struct kmem_cache_node), GFP_KERNEL);
+#endif
+
+        /* Able to allocate the per node structures */
+        slab_state = PARTIAL;
+
+        /* Caches that are not of the two-to-the-power-of size */
+        create_kmalloc_cache(&kmalloc_caches[1],
+                                "kmalloc-96", 96, GFP_KERNEL);
+        create_kmalloc_cache(&kmalloc_caches[2],
+                                "kmalloc-192", 192, GFP_KERNEL);
+
+        for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
+                create_kmalloc_cache(&kmalloc_caches[i],
+                        "kmalloc", 1 << i, GFP_KERNEL);
+
+        slab_state = UP;
+
+        /* Provide the correct kmalloc names now that the caches are up */
+        for (i = KMALLOC_SHIFT_LOW; i <= KMALLOC_SHIFT_HIGH; i++)
+                kmalloc_caches[i]. name =
+                        kasprintf(GFP_KERNEL, "kmalloc-%d", 1 << i);
+
+#ifdef CONFIG_SMP
+        register_cpu_notifier(&slab_notifier);
+#endif
+
+        if (nr_cpu_ids) /* Remove when nr_cpu_ids is fixed upstream ! */
+                kmem_size = offsetof(struct kmem_cache, cpu_slab)
+                         + nr_cpu_ids * sizeof(struct page *);
+
+        printk(KERN_INFO "SLUB: Genslabs=%d, HWalign=%d, Order=%d-%d, MinObjects=%d,"
+                " Processors=%d, Nodes=%d\n",
+                KMALLOC_SHIFT_HIGH, L1_CACHE_BYTES,
+                slub_min_order, slub_max_order, slub_min_objects,
+                nr_cpu_ids, nr_node_ids);
+}
+
+/*
+ * Find a mergeable slab cache
+ */
+static int slab_unmergeable(struct kmem_cache *s)
+{
+        if (slub_nomerge || (s->flags & SLUB_NEVER_MERGE))
+                return 1;
+
+        if (s->ctor || s->dtor)
+                return 1;
+
+        return 0;
+}
+
+static struct kmem_cache *find_mergeable(size_t size,
+                size_t align, unsigned long flags,
+                void (*ctor)(void *, struct kmem_cache *, unsigned long),
+                void (*dtor)(void *, struct kmem_cache *, unsigned long))
+{
+        struct list_head *h;
+
+        if (slub_nomerge || (flags & SLUB_NEVER_MERGE))
+                return NULL;
+
+        if (ctor || dtor)
+                return NULL;
+
+        size = ALIGN(size, sizeof(void *));
+        align = calculate_alignment(flags, align, size);
+        size = ALIGN(size, align);
+
+        list_for_each(h, &slab_caches) {
+                struct kmem_cache *s =
+                        container_of(h, struct kmem_cache, list);
+
+                if (slab_unmergeable(s))
+                        continue;
+
+                if (size > s->size)
+                        continue;
+
+                if (((flags | slub_debug) & SLUB_MERGE_SAME) !=
+                        (s->flags & SLUB_MERGE_SAME))
+                                continue;
+                /*
+                 * Check if alignment is compatible.
+                 * Courtesy of Adrian Drzewiecki
+                 */
+                if ((s->size & ~(align -1)) != s->size)
+                        continue;
+
+                if (s->size - size >= sizeof(void *))
+                        continue;
+
+                return s;
+        }
+        return NULL;
+}
+
+struct kmem_cache *kmem_cache_create(const char *name, size_t size,
+                size_t align, unsigned long flags,
+                void (*ctor)(void *, struct kmem_cache *, unsigned long),
+                void (*dtor)(void *, struct kmem_cache *, unsigned long))
+{
+        struct kmem_cache *s;
+
+        down_write(&slub_lock);
+        s = find_mergeable(size, align, flags, dtor, ctor);
+        if (s) {
+                s->refcount++;
+                /*
+                 * Adjust the object sizes so that we clear
+                 * the complete object on kzalloc.
+                 */
+                s->objsize = max(s->objsize, (int)size);
+                s->inuse = max_t(int, s->inuse, ALIGN(size, sizeof(void *)));
+                if (sysfs_slab_alias(s, name))
+                        goto err;
+        } else {
+                s = kmalloc(kmem_size, GFP_KERNEL);
+                if (s && kmem_cache_open(s, GFP_KERNEL, name,
+                                size, align, flags, ctor, dtor)) {
+                        if (sysfs_slab_add(s)) {
+                                kfree(s);
+                                goto err;
+                        }
+                        list_add(&s->list, &slab_caches);
+                } else
+                        kfree(s);
+        }
+        up_write(&slub_lock);
+        return s;
+
+err:
+        up_write(&slub_lock);
+        if (flags & SLAB_PANIC)
+                panic("Cannot create slabcache %s\n", name);
+        else
+                s = NULL;
+        return s;
+}
+EXPORT_SYMBOL(kmem_cache_create);
+
+void *kmem_cache_zalloc(struct kmem_cache *s, gfp_t flags)
+{
+        void *x;
+
+        x = kmem_cache_alloc(s, flags);
+        if (x)
+                memset(x, 0, s->objsize);
+        return x;
+}
+EXPORT_SYMBOL(kmem_cache_zalloc);
+
+#ifdef CONFIG_SMP
+static void for_all_slabs(void (*func)(struct kmem_cache *, int), int cpu)
+{
+        struct list_head *h;
+
+        down_read(&slub_lock);
+        list_for_each(h, &slab_caches) {
+                struct kmem_cache *s =
+                        container_of(h, struct kmem_cache, list);
+
+                func(s, cpu);
+        }
+        up_read(&slub_lock);
+}
+
+/*
+ * Use the cpu notifier to insure that the slab are flushed
+ * when necessary.
+ */
+static int __cpuinit slab_cpuup_callback(struct notifier_block *nfb,
+                unsigned long action, void *hcpu)
+{
+        long cpu = (long)hcpu;
+
+        switch (action) {
+        case CPU_UP_CANCELED:
+        case CPU_DEAD:
+                for_all_slabs(__flush_cpu_slab, cpu);
+                break;
+        default:
+                break;
+        }
+        return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata slab_notifier =
+        { &slab_cpuup_callback, NULL, 0 };
+
+#endif
+
+/***************************************************************
+ *      Compatiblility definitions
+ **************************************************************/
+
+int kmem_cache_shrink(struct kmem_cache *s)
+{
+        flush_all(s);
+        return 0;
+}
+EXPORT_SYMBOL(kmem_cache_shrink);
+
+#ifdef CONFIG_NUMA
+
+/*****************************************************************
+ * Generic reaper used to support the page allocator
+ * (the cpu slabs are reaped by a per slab workqueue).
+ *
+ * Maybe move this to the page allocator?
+ ****************************************************************/
+
+static DEFINE_PER_CPU(unsigned long, reap_node);
+
+static void init_reap_node(int cpu)
+{
+        int node;
+
+        node = next_node(cpu_to_node(cpu), node_online_map);
+        if (node == MAX_NUMNODES)
+                node = first_node(node_online_map);
+
+        __get_cpu_var(reap_node) = node;
+}
+
+static void next_reap_node(void)
+{
+        int node = __get_cpu_var(reap_node);
+
+        /*
+         * Also drain per cpu pages on remote zones
+         */
+        if (node != numa_node_id())
+                drain_node_pages(node);
+
+        node = next_node(node, node_online_map);
+        if (unlikely(node >= MAX_NUMNODES))
+                node = first_node(node_online_map);
+        __get_cpu_var(reap_node) = node;
+}
+#else
+#define init_reap_node(cpu) do { } while (0)
+#define next_reap_node(void) do { } while (0)
+#endif
+
+#define REAPTIMEOUT_CPUC        (2*HZ)
+
+#ifdef CONFIG_SMP
+static DEFINE_PER_CPU(struct delayed_work, reap_work);
+
+static void cache_reap(struct work_struct *unused)
+{
+        next_reap_node();
+        refresh_cpu_vm_stats(smp_processor_id());
+        schedule_delayed_work(&__get_cpu_var(reap_work),
+                                      REAPTIMEOUT_CPUC);
+}
+
+static void __devinit start_cpu_timer(int cpu)
+{
+        struct delayed_work *reap_work = &per_cpu(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(reap_work, cache_reap);
+                schedule_delayed_work_on(cpu, reap_work, HZ + 3 * cpu);
+        }
+}
+
+static int __init cpucache_init(void)
+{
+        int cpu;
+
+        /*
+         * Register the timers that drain pcp pages and update vm statistics
+         */
+        for_each_online_cpu(cpu)
+                start_cpu_timer(cpu);
+        return 0;
+}
+__initcall(cpucache_init);
+#endif
+
+#ifdef SLUB_RESILIENCY_TEST
+static unsigned long validate_slab_cache(struct kmem_cache *s);
+
+static void resiliency_test(void)
+{
+        u8 *p;
+
+        printk(KERN_ERR "SLUB resiliency testing\n");
+        printk(KERN_ERR "-----------------------\n");
+        printk(KERN_ERR "A. Corruption after allocation\n");
+
+        p = kzalloc(16, GFP_KERNEL);
+        p[16] = 0x12;
+        printk(KERN_ERR "\n1. kmalloc-16: Clobber Redzone/next pointer"
+                        " 0x12->0x%p\n\n", p + 16);
+
+        validate_slab_cache(kmalloc_caches + 4);
+
+        /* Hmmm... The next two are dangerous */
+        p = kzalloc(32, GFP_KERNEL);
+        p[32 + sizeof(void *)] = 0x34;
+        printk(KERN_ERR "\n2. kmalloc-32: Clobber next pointer/next slab"
+                        " 0x34 -> -0x%p\n", p);
+        printk(KERN_ERR "If allocated object is overwritten then not detectable\n\n");
+
+        validate_slab_cache(kmalloc_caches + 5);
+        p = kzalloc(64, GFP_KERNEL);
+        p += 64 + (get_cycles() & 0xff) * sizeof(void *);
+        *p = 0x56;
+        printk(KERN_ERR "\n3. kmalloc-64: corrupting random byte 0x56->0x%p\n",
+                                                                        p);
+        printk(KERN_ERR "If allocated object is overwritten then not detectable\n\n");
+        validate_slab_cache(kmalloc_caches + 6);
+
+        printk(KERN_ERR "\nB. Corruption after free\n");
+        p = kzalloc(128, GFP_KERNEL);
+        kfree(p);
+        *p = 0x78;
+        printk(KERN_ERR "1. kmalloc-128: Clobber first word 0x78->0x%p\n\n", p);
+        validate_slab_cache(kmalloc_caches + 7);
+
+        p = kzalloc(256, GFP_KERNEL);
+        kfree(p);
+        p[50] = 0x9a;
+        printk(KERN_ERR "\n2. kmalloc-256: Clobber 50th byte 0x9a->0x%p\n\n", p);
+        validate_slab_cache(kmalloc_caches + 8);
+
+        p = kzalloc(512, GFP_KERNEL);
+        kfree(p);
+        p[512] = 0xab;
+        printk(KERN_ERR "\n3. kmalloc-512: Clobber redzone 0xab->0x%p\n\n", p);
+        validate_slab_cache(kmalloc_caches + 9);
+}
+#else
+static void resiliency_test(void) {};
+#endif
+
+/*
+ * These are not as efficient as kmalloc for the non debug case.
+ * We do not have the page struct available so we have to touch one
+ * cacheline in struct kmem_cache to check slab flags.
+ */
+void *__kmalloc_track_caller(size_t size, gfp_t gfpflags, void *caller)
+{
+        struct kmem_cache *s = get_slab(size, gfpflags);
+        void *object;
+
+        if (!s)
+                return NULL;
+
+        object = kmem_cache_alloc(s, gfpflags);
+
+        if (object && (s->flags & SLAB_STORE_USER))
+                set_track(s, object, TRACK_ALLOC, caller);
+
+        return object;
+}
+
+void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
+                                        int node, void *caller)
+{
+        struct kmem_cache *s = get_slab(size, gfpflags);
+        void *object;
+
+        if (!s)
+                return NULL;
+
+        object = kmem_cache_alloc_node(s, gfpflags, node);
+
+        if (object && (s->flags & SLAB_STORE_USER))
+                set_track(s, object, TRACK_ALLOC, caller);
+
+        return object;
+}
+
+#ifdef CONFIG_SYSFS
+
+static unsigned long count_partial(struct kmem_cache_node *n)
+{
+        unsigned long flags;
+        unsigned long x = 0;
+        struct page *page;
+
+        spin_lock_irqsave(&n->list_lock, flags);
+        list_for_each_entry(page, &n->partial, lru)
+                x += page->inuse;
+        spin_unlock_irqrestore(&n->list_lock, flags);
+        return x;
+}
+
+enum slab_stat_type {
+        SL_FULL,
+        SL_PARTIAL,
+        SL_CPU,
+        SL_OBJECTS
+};
+
+#define SO_FULL         (1 << SL_FULL)
+#define SO_PARTIAL      (1 << SL_PARTIAL)
+#define SO_CPU          (1 << SL_CPU)
+#define SO_OBJECTS      (1 << SL_OBJECTS)
+
+static unsigned long slab_objects(struct kmem_cache *s,
+                        char *buf, unsigned long flags)
+{
+        unsigned long total = 0;
+        int cpu;
+        int node;
+        int x;
+        unsigned long *nodes;
+        unsigned long *per_cpu;
+
+        nodes = kzalloc(2 * sizeof(unsigned long) * nr_node_ids, GFP_KERNEL);
+        per_cpu = nodes + nr_node_ids;
+
+        for_each_possible_cpu(cpu) {
+                struct page *page = s->cpu_slab[cpu];
+                int node;
+
+                if (page) {
+                        node = page_to_nid(page);
+                        if (flags & SO_CPU) {
+                                int x = 0;
+
+                                if (flags & SO_OBJECTS)
+                                        x = page->inuse;
+                                else
+                                        x = 1;
+                                total += x;
+                                nodes[node] += x;
+                        }
+                        per_cpu[node]++;
+                }
+        }
+
+        for_each_online_node(node) {
+                struct kmem_cache_node *n = get_node(s, node);
+
+                if (flags & SO_PARTIAL) {
+                        if (flags & SO_OBJECTS)
+                                x = count_partial(n);
+                        else
+                                x = n->nr_partial;
+                        total += x;
+                        nodes[node] += x;
+                }
+
+                if (flags & SO_FULL) {
+                        int full_slabs = atomic_read(&n->nr_slabs)
+                                        - per_cpu[node]
+                                        - n->nr_partial;
+
+                        if (flags & SO_OBJECTS)
+                                x = full_slabs * s->objects;
+                        else
+                                x = full_slabs;
+                        total += x;
+                        nodes[node] += x;
+                }
+        }
+
+        x = sprintf(buf, "%lu", total);
+#ifdef CONFIG_NUMA
+        for_each_online_node(node)
+                if (nodes[node])
+                        x += sprintf(buf + x, " N%d=%lu",
+                                        node, nodes[node]);
+#endif
+        kfree(nodes);
+        return x + sprintf(buf + x, "\n");
+}
+
+static int any_slab_objects(struct kmem_cache *s)
+{
+        int node;
+        int cpu;
+
+        for_each_possible_cpu(cpu)
+                if (s->cpu_slab[cpu])
+                        return 1;
+
+        for_each_node(node) {
+                struct kmem_cache_node *n = get_node(s, node);
+
+                if (n->nr_partial || atomic_read(&n->nr_slabs))
+                        return 1;
+        }
+        return 0;
+}
+
+#define to_slab_attr(n) container_of(n, struct slab_attribute, attr)
+#define to_slab(n) container_of(n, struct kmem_cache, kobj);
+
+struct slab_attribute {
+        struct attribute attr;
+        ssize_t (*show)(struct kmem_cache *s, char *buf);
+        ssize_t (*store)(struct kmem_cache *s, const char *x, size_t count);
+};
+
+#define SLAB_ATTR_RO(_name) \
+        static struct slab_attribute _name##_attr = __ATTR_RO(_name)
+
+#define SLAB_ATTR(_name) \
+        static struct slab_attribute _name##_attr =  \
+        __ATTR(_name, 0644, _name##_show, _name##_store)
+
+
+static ssize_t slab_size_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", s->size);
+}
+SLAB_ATTR_RO(slab_size);
+
+static ssize_t align_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", s->align);
+}
+SLAB_ATTR_RO(align);
+
+static ssize_t object_size_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", s->objsize);
+}
+SLAB_ATTR_RO(object_size);
+
+static ssize_t objs_per_slab_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", s->objects);
+}
+SLAB_ATTR_RO(objs_per_slab);
+
+static ssize_t order_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", s->order);
+}
+SLAB_ATTR_RO(order);
+
+static ssize_t ctor_show(struct kmem_cache *s, char *buf)
+{
+        if (s->ctor) {
+                int n = sprint_symbol(buf, (unsigned long)s->ctor);
+
+                return n + sprintf(buf + n, "\n");
+        }
+        return 0;
+}
+SLAB_ATTR_RO(ctor);
+
+static ssize_t dtor_show(struct kmem_cache *s, char *buf)
+{
+        if (s->dtor) {
+                int n = sprint_symbol(buf, (unsigned long)s->dtor);
+
+                return n + sprintf(buf + n, "\n");
+        }
+        return 0;
+}
+SLAB_ATTR_RO(dtor);
+
+static ssize_t aliases_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", s->refcount - 1);
+}
+SLAB_ATTR_RO(aliases);
+
+static ssize_t slabs_show(struct kmem_cache *s, char *buf)
+{
+        return slab_objects(s, buf, SO_FULL|SO_PARTIAL|SO_CPU);
+}
+SLAB_ATTR_RO(slabs);
+
+static ssize_t partial_show(struct kmem_cache *s, char *buf)
+{
+        return slab_objects(s, buf, SO_PARTIAL);
+}
+SLAB_ATTR_RO(partial);
+
+static ssize_t cpu_slabs_show(struct kmem_cache *s, char *buf)
+{
+        return slab_objects(s, buf, SO_CPU);
+}
+SLAB_ATTR_RO(cpu_slabs);
+
+static ssize_t objects_show(struct kmem_cache *s, char *buf)
+{
+        return slab_objects(s, buf, SO_FULL|SO_PARTIAL|SO_CPU|SO_OBJECTS);
+}
+SLAB_ATTR_RO(objects);
+
+static ssize_t sanity_checks_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", !!(s->flags & SLAB_DEBUG_FREE));
+}
+
+static ssize_t sanity_checks_store(struct kmem_cache *s,
+                                const char *buf, size_t length)
+{
+        s->flags &= ~SLAB_DEBUG_FREE;
+        if (buf[0] == '1')
+                s->flags |= SLAB_DEBUG_FREE;
+        return length;
+}
+SLAB_ATTR(sanity_checks);
+
+static ssize_t trace_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", !!(s->flags & SLAB_TRACE));
+}
+
+static ssize_t trace_store(struct kmem_cache *s, const char *buf,
+                                                        size_t length)
+{
+        s->flags &= ~SLAB_TRACE;
+        if (buf[0] == '1')
+                s->flags |= SLAB_TRACE;
+        return length;
+}
+SLAB_ATTR(trace);
+
+static ssize_t reclaim_account_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", !!(s->flags & SLAB_RECLAIM_ACCOUNT));
+}
+
+static ssize_t reclaim_account_store(struct kmem_cache *s,
+                                const char *buf, size_t length)
+{
+        s->flags &= ~SLAB_RECLAIM_ACCOUNT;
+        if (buf[0] == '1')
+                s->flags |= SLAB_RECLAIM_ACCOUNT;
+        return length;
+}
+SLAB_ATTR(reclaim_account);
+
+static ssize_t hwcache_align_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", !!(s->flags &
+                (SLAB_HWCACHE_ALIGN|SLAB_MUST_HWCACHE_ALIGN)));
+}
+SLAB_ATTR_RO(hwcache_align);
+
+#ifdef CONFIG_ZONE_DMA
+static ssize_t cache_dma_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", !!(s->flags & SLAB_CACHE_DMA));
+}
+SLAB_ATTR_RO(cache_dma);
+#endif
+
+static ssize_t destroy_by_rcu_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", !!(s->flags & SLAB_DESTROY_BY_RCU));
+}
+SLAB_ATTR_RO(destroy_by_rcu);
+
+static ssize_t red_zone_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", !!(s->flags & SLAB_RED_ZONE));
+}
+
+static ssize_t red_zone_store(struct kmem_cache *s,
+                                const char *buf, size_t length)
+{
+        if (any_slab_objects(s))
+                return -EBUSY;
+
+        s->flags &= ~SLAB_RED_ZONE;
+        if (buf[0] == '1')
+                s->flags |= SLAB_RED_ZONE;
+        calculate_sizes(s);
+        return length;
+}
+SLAB_ATTR(red_zone);
+
+static ssize_t poison_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", !!(s->flags & SLAB_POISON));
+}
+
+static ssize_t poison_store(struct kmem_cache *s,
+                                const char *buf, size_t length)
+{
+        if (any_slab_objects(s))
+                return -EBUSY;
+
+        s->flags &= ~SLAB_POISON;
+        if (buf[0] == '1')
+                s->flags |= SLAB_POISON;
+        calculate_sizes(s);
+        return length;
+}
+SLAB_ATTR(poison);
+
+static ssize_t store_user_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", !!(s->flags & SLAB_STORE_USER));
+}
+
+static ssize_t store_user_store(struct kmem_cache *s,
+                                const char *buf, size_t length)
+{
+        if (any_slab_objects(s))
+                return -EBUSY;
+
+        s->flags &= ~SLAB_STORE_USER;
+        if (buf[0] == '1')
+                s->flags |= SLAB_STORE_USER;
+        calculate_sizes(s);
+        return length;
+}
+SLAB_ATTR(store_user);
+
+#ifdef CONFIG_NUMA
+static ssize_t defrag_ratio_show(struct kmem_cache *s, char *buf)
+{
+        return sprintf(buf, "%d\n", s->defrag_ratio / 10);
+}
+
+static ssize_t defrag_ratio_store(struct kmem_cache *s,
+                                const char *buf, size_t length)
+{
+        int n = simple_strtoul(buf, NULL, 10);
+
+        if (n < 100)
+                s->defrag_ratio = n * 10;
+        return length;
+}
+SLAB_ATTR(defrag_ratio);
+#endif
+
+static struct attribute * slab_attrs[] = {
+        &slab_size_attr.attr,
+        &object_size_attr.attr,
+        &objs_per_slab_attr.attr,
+        &order_attr.attr,
+        &objects_attr.attr,
+        &slabs_attr.attr,
+        &partial_attr.attr,
+        &cpu_slabs_attr.attr,
+        &ctor_attr.attr,
+        &dtor_attr.attr,
+        &aliases_attr.attr,
+        &align_attr.attr,
+        &sanity_checks_attr.attr,
+        &trace_attr.attr,
+        &hwcache_align_attr.attr,
+        &reclaim_account_attr.attr,
+        &destroy_by_rcu_attr.attr,
+        &red_zone_attr.attr,
+        &poison_attr.attr,
+        &store_user_attr.attr,
+#ifdef CONFIG_ZONE_DMA
+        &cache_dma_attr.attr,
+#endif
+#ifdef CONFIG_NUMA
+        &defrag_ratio_attr.attr,
+#endif
+        NULL
+};
+
+static struct attribute_group slab_attr_group = {
+        .attrs = slab_attrs,
+};
+
+static ssize_t slab_attr_show(struct kobject *kobj,
+                                struct attribute *attr,
+                                char *buf)
+{
+        struct slab_attribute *attribute;
+        struct kmem_cache *s;
+        int err;
+
+        attribute = to_slab_attr(attr);
+        s = to_slab(kobj);
+
+        if (!attribute->show)
+                return -EIO;
+
+        err = attribute->show(s, buf);
+
+        return err;
+}
+
+static ssize_t slab_attr_store(struct kobject *kobj,
+                                struct attribute *attr,
+                                const char *buf, size_t len)
+{
+        struct slab_attribute *attribute;
+        struct kmem_cache *s;
+        int err;
+
+        attribute = to_slab_attr(attr);
+        s = to_slab(kobj);
+
+        if (!attribute->store)
+                return -EIO;
+
+        err = attribute->store(s, buf, len);
+
+        return err;
+}
+
+static struct sysfs_ops slab_sysfs_ops = {
+        .show = slab_attr_show,
+        .store = slab_attr_store,
+};
+
+static struct kobj_type slab_ktype = {
+        .sysfs_ops = &slab_sysfs_ops,
+};
+
+static int uevent_filter(struct kset *kset, struct kobject *kobj)
+{
+        struct kobj_type *ktype = get_ktype(kobj);
+
+        if (ktype == &slab_ktype)
+                return 1;
+        return 0;
+}
+
+static struct kset_uevent_ops slab_uevent_ops = {
+        .filter = uevent_filter,
+};
+
+decl_subsys(slab, &slab_ktype, &slab_uevent_ops);
+
+#define ID_STR_LENGTH 64
+
+/* Create a unique string id for a slab cache:
+ * format
+ * :[flags-]size:[memory address of kmemcache]
+ */
+static char *create_unique_id(struct kmem_cache *s)
+{
+        char *name = kmalloc(ID_STR_LENGTH, GFP_KERNEL);
+        char *p = name;
+
+        BUG_ON(!name);
+
+        *p++ = ':';
+        /*
+         * First flags affecting slabcache operations. We will only
+         * get here for aliasable slabs so we do not need to support
+         * too many flags. The flags here must cover all flags that
+         * are matched during merging to guarantee that the id is
+         * unique.
+         */
+        if (s->flags & SLAB_CACHE_DMA)
+                *p++ = 'd';
+        if (s->flags & SLAB_RECLAIM_ACCOUNT)
+                *p++ = 'a';
+        if (s->flags & SLAB_DEBUG_FREE)
+                *p++ = 'F';
+        if (p != name + 1)
+                *p++ = '-';
+        p += sprintf(p, "%07d", s->size);
+        BUG_ON(p > name + ID_STR_LENGTH - 1);
+        return name;
+}
+
+static int sysfs_slab_add(struct kmem_cache *s)
+{
+        int err;
+        const char *name;
+        int unmergeable;
+
+        if (slab_state < SYSFS)
+                /* Defer until later */
+                return 0;
+
+        unmergeable = slab_unmergeable(s);
+        if (unmergeable) {
+                /*
+                 * Slabcache can never be merged so we can use the name proper.
+                 * This is typically the case for debug situations. In that
+                 * case we can catch duplicate names easily.
+                 */
+                sysfs_remove_link(&slab_subsys.kset.kobj, s->name);
+                name = s->name;
+        } else {
+                /*
+                 * Create a unique name for the slab as a target
+                 * for the symlinks.
+                 */
+                name = create_unique_id(s);
+        }
+
+        kobj_set_kset_s(s, slab_subsys);
+        kobject_set_name(&s->kobj, name);
+        kobject_init(&s->kobj);
+        err = kobject_add(&s->kobj);
+        if (err)
+                return err;
+
+        err = sysfs_create_group(&s->kobj, &slab_attr_group);
+        if (err)
+                return err;
+        kobject_uevent(&s->kobj, KOBJ_ADD);
+        if (!unmergeable) {
+                /* Setup first alias */
+                sysfs_slab_alias(s, s->name);
+                kfree(name);
+        }
+        return 0;
+}
+
+static void sysfs_slab_remove(struct kmem_cache *s)
+{
+        kobject_uevent(&s->kobj, KOBJ_REMOVE);
+        kobject_del(&s->kobj);
+}
+
+/*
+ * Need to buffer aliases during bootup until sysfs becomes
+ * available lest we loose that information.
+ */
+struct saved_alias {
+        struct kmem_cache *s;
+        const char *name;
+        struct saved_alias *next;
+};
+
+struct saved_alias *alias_list;
+
+static int sysfs_slab_alias(struct kmem_cache *s, const char *name)
+{
+        struct saved_alias *al;
+
+        if (slab_state == SYSFS) {
+                /*
+                 * If we have a leftover link then remove it.
+                 */
+                sysfs_remove_link(&slab_subsys.kset.kobj, name);
+                return sysfs_create_link(&slab_subsys.kset.kobj,
+                                                &s->kobj, name);
+        }
+
+        al = kmalloc(sizeof(struct saved_alias), GFP_KERNEL);
+        if (!al)
+                return -ENOMEM;
+
+        al->s = s;
+        al->name = name;
+        al->next = alias_list;
+        alias_list = al;
+        return 0;
+}
+
+static int __init slab_sysfs_init(void)
+{
+        int err;
+
+        err = subsystem_register(&slab_subsys);
+        if (err) {
+                printk(KERN_ERR "Cannot register slab subsystem.\n");
+                return -ENOSYS;
+        }
+
+        finish_bootstrap();
+
+        while (alias_list) {
+                struct saved_alias *al = alias_list;
+
+                alias_list = alias_list->next;
+                err = sysfs_slab_alias(al->s, al->name);
+                BUG_ON(err);
+                kfree(al);
+        }
+
+        resiliency_test();
+        return 0;
+}
+
+__initcall(slab_sysfs_init);
+#else
+__initcall(finish_bootstrap);
+#endif