include/linux/slub_def.h

   1 #ifndef _LINUX_SLUB_DEF_H
   2 #define _LINUX_SLUB_DEF_H
   3
   4 /*
   5  * SLUB : A Slab allocator without object queues.
   6  *
   7  * (C) 2007 SGI, Christoph Lameter
   8  */
   9 #include <linux/types.h>
  10 #include <linux/gfp.h>
  11 #include <linux/bug.h>
  12 #include <linux/workqueue.h>
  13 #include <linux/kobject.h>
  14
  15 #include <linux/kmemleak.h>
  16
  17 enum stat_item {
  18         ALLOC_FASTPATH,         /* Allocation from cpu slab */
  19         ALLOC_SLOWPATH,         /* Allocation by getting a new cpu slab */
  20         FREE_FASTPATH,          /* Free to cpu slub */
  21         FREE_SLOWPATH,          /* Freeing not to cpu slab */
  22         FREE_FROZEN,            /* Freeing to frozen slab */
  23         FREE_ADD_PARTIAL,       /* Freeing moves slab to partial list */
  24         FREE_REMOVE_PARTIAL,    /* Freeing removes last object */
  25         ALLOC_FROM_PARTIAL,     /* Cpu slab acquired from node partial list */
  26         ALLOC_SLAB,             /* Cpu slab acquired from page allocator */
  27         ALLOC_REFILL,           /* Refill cpu slab from slab freelist */
  28         ALLOC_NODE_MISMATCH,    /* Switching cpu slab */
  29         FREE_SLAB,              /* Slab freed to the page allocator */
  30         CPUSLAB_FLUSH,          /* Abandoning of the cpu slab */
  31         DEACTIVATE_FULL,        /* Cpu slab was full when deactivated */
  32         DEACTIVATE_EMPTY,       /* Cpu slab was empty when deactivated */
  33         DEACTIVATE_TO_HEAD,     /* Cpu slab was moved to the head of partials */
  34         DEACTIVATE_TO_TAIL,     /* Cpu slab was moved to the tail of partials */
  35         DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */
  36         DEACTIVATE_BYPASS,      /* Implicit deactivation */
  37         ORDER_FALLBACK,         /* Number of times fallback was necessary */
  38         CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */
  39         CMPXCHG_DOUBLE_FAIL,    /* Number of times that cmpxchg double did not match */
  40         CPU_PARTIAL_ALLOC,      /* Used cpu partial on alloc */
  41         CPU_PARTIAL_FREE,       /* Refill cpu partial on free */
  42         CPU_PARTIAL_NODE,       /* Refill cpu partial from node partial */
  43         CPU_PARTIAL_DRAIN,      /* Drain cpu partial to node partial */
  44         NR_SLUB_STAT_ITEMS };
  45
  46 struct kmem_cache_cpu {
  47         void **freelist;        /* Pointer to next available object */
  48         unsigned long tid;      /* Globally unique transaction id */
  49         struct page *page;      /* The slab from which we are allocating */
  50         struct page *partial;   /* Partially allocated frozen slabs */
  51 #ifdef CONFIG_SLUB_STATS
  52         unsigned stat[NR_SLUB_STAT_ITEMS];
  53 #endif
  54 };
  55
  56 struct kmem_cache_node {
  57         spinlock_t list_lock;   /* Protect partial list and nr_partial */
  58         unsigned long nr_partial;
  59         struct list_head partial;
  60 #ifdef CONFIG_SLUB_DEBUG
  61         atomic_long_t nr_slabs;
  62         atomic_long_t total_objects;
  63         struct list_head full;
  64 #endif
  65 };
  66
  67 /*
  68  * Word size structure that can be atomically updated or read and that
  69  * contains both the order and the number of objects that a slab of the
  70  * given order would contain.
  71  */
  72 struct kmem_cache_order_objects {
  73         unsigned long x;
  74 };
  75
  76 /*
  77  * Slab cache management.
  78  */
  79 struct kmem_cache {
  80         struct kmem_cache_cpu __percpu *cpu_slab;
  81         /* Used for retriving partial slabs etc */
  82         unsigned long flags;
  83         unsigned long min_partial;
  84         int size;               /* The size of an object including meta data */
  85         int object_size;        /* The size of an object without meta data */
  86         int offset;             /* Free pointer offset. */
  87         int cpu_partial;        /* Number of per cpu partial objects to keep around */
  88         struct kmem_cache_order_objects oo;
  89
  90         /* Allocation and freeing of slabs */
  91         struct kmem_cache_order_objects max;
  92         struct kmem_cache_order_objects min;
  93         gfp_t allocflags;       /* gfp flags to use on each alloc */
  94         int refcount;           /* Refcount for slab cache destroy */
  95         void (*ctor)(void *);
  96         int inuse;              /* Offset to metadata */
  97         int align;              /* Alignment */
  98         int reserved;           /* Reserved bytes at the end of slabs */
  99         const char *name;       /* Name (only for display!) */
 100         struct list_head list;  /* List of slab caches */
 101 #ifdef CONFIG_SYSFS
 102         struct kobject kobj;    /* For sysfs */
 103 #endif
 104 #ifdef CONFIG_MEMCG_KMEM
 105         struct memcg_cache_params *memcg_params;
 106         int max_attr_size; /* for propagation, maximum size of a stored attr */
 107 #endif
 108
 109 #ifdef CONFIG_NUMA
 110         /*
 111          * Defragmentation by allocating from a remote node.
 112          */
 113         int remote_node_defrag_ratio;
 114 #endif
 115         struct kmem_cache_node *node[MAX_NUMNODES];
 116 };
 117
 118 void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
 119 void *__kmalloc(size_t size, gfp_t flags);
 120
 121 static __always_inline void *
 122 kmalloc_order(size_t size, gfp_t flags, unsigned int order)
 123 {
 124         void *ret;
 125
 126         flags |= (__GFP_COMP | __GFP_KMEMCG);
 127         ret = (void *) __get_free_pages(flags, order);
 128         kmemleak_alloc(ret, size, 1, flags);
 129         return ret;
 130 }
 131
 132 /**
 133  * Calling this on allocated memory will check that the memory
 134  * is expected to be in use, and print warnings if not.
 135  */
 136 #ifdef CONFIG_SLUB_DEBUG
 137 extern bool verify_mem_not_deleted(const void *x);
 138 #else
 139 static inline bool verify_mem_not_deleted(const void *x)
 140 {
 141         return true;
 142 }
 143 #endif
 144
 145 #ifdef CONFIG_TRACING
 146 extern void *
 147 kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size);
 148 extern void *kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order);
 149 #else
 150 static __always_inline void *
 151 kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t gfpflags, size_t size)
 152 {
 153         return kmem_cache_alloc(s, gfpflags);
 154 }
 155
 156 static __always_inline void *
 157 kmalloc_order_trace(size_t size, gfp_t flags, unsigned int order)
 158 {
 159         return kmalloc_order(size, flags, order);
 160 }
 161 #endif
 162
 163 static __always_inline void *kmalloc_large(size_t size, gfp_t flags)
 164 {
 165         unsigned int order = get_order(size);
 166         return kmalloc_order_trace(size, flags, order);
 167 }
 168
 169 static __always_inline void *kmalloc(size_t size, gfp_t flags)
 170 {
 171         if (__builtin_constant_p(size)) {
 172                 if (size > KMALLOC_MAX_CACHE_SIZE)
 173                         return kmalloc_large(size, flags);
 174
 175                 if (!(flags & GFP_DMA)) {
 176                         int index = kmalloc_index(size);
 177
 178                         if (!index)
 179                                 return ZERO_SIZE_PTR;
 180
 181                         return kmem_cache_alloc_trace(kmalloc_caches[index],
 182                                         flags, size);
 183                 }
 184         }
 185         return __kmalloc(size, flags);
 186 }
 187
 188 #ifdef CONFIG_NUMA
 189 void *__kmalloc_node(size_t size, gfp_t flags, int node);
 190 void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
 191
 192 #ifdef CONFIG_TRACING
 193 extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
 194                                            gfp_t gfpflags,
 195                                            int node, size_t size);
 196 #else
 197 static __always_inline void *
 198 kmem_cache_alloc_node_trace(struct kmem_cache *s,
 199                               gfp_t gfpflags,
 200                               int node, size_t size)
 201 {
 202         return kmem_cache_alloc_node(s, gfpflags, node);
 203 }
 204 #endif
 205
 206 static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
 207 {
 208         if (__builtin_constant_p(size) &&
 209                 size <= KMALLOC_MAX_CACHE_SIZE && !(flags & GFP_DMA)) {
 210                 int index = kmalloc_index(size);
 211
 212                 if (!index)
 213                         return ZERO_SIZE_PTR;
 214
 215                 return kmem_cache_alloc_node_trace(kmalloc_caches[index],
 216                                flags, node, size);
 217         }
 218         return __kmalloc_node(size, flags, node);
 219 }
 220 #endif
 221
 222 #endif /* _LINUX_SLUB_DEF_H */