LXR linux/include/linux/slab

   1#ifndef _LINUX_SLAB_DEF_H
   2#define _LINUX_SLAB_DEF_H
   3
   4/*
   5 * Definitions unique to the original Linux SLAB allocator.
   6 */
   7
   8struct kmem_cache {
   9/* 1) Cache tunables. Protected by cache_chain_mutex */
  10        unsigned int batchcount;
  11        unsigned int limit;
  12        unsigned int shared;
  13
  14        unsigned int size;
  15        u32 reciprocal_buffer_size;
  16/* 2) touched by every alloc & free from the backend */
  17
  18        unsigned int flags;             /* constant flags */
  19        unsigned int num;               /* # of objs per slab */
  20
  21/* 3) cache_grow/shrink */
  22        /* order of pgs per slab (2^n) */
  23        unsigned int gfporder;
  24
  25        /* force GFP flags, e.g. GFP_DMA */
  26        gfp_t allocflags;
  27
  28        size_t colour;                  /* cache colouring range */
  29        unsigned int colour_off;        /* colour offset */
  30        struct kmem_cache *slabp_cache;
  31        unsigned int slab_size;
  32
  33        /* constructor func */
  34        void (*ctor)(void *obj);
  35
  36/* 4) cache creation/removal */
  37        const char *name;
  38        struct list_head list;
  39        int refcount;
  40        int object_size;
  41        int align;
  42
  43/* 5) statistics */
  44#ifdef CONFIG_DEBUG_SLAB
  45        unsigned long num_active;
  46        unsigned long num_allocations;
  47        unsigned long high_mark;
  48        unsigned long grown;
  49        unsigned long reaped;
  50        unsigned long errors;
  51        unsigned long max_freeable;
  52        unsigned long node_allocs;
  53        unsigned long node_frees;
  54        unsigned long node_overflow;
  55        atomic_t allochit;
  56        atomic_t allocmiss;
  57        atomic_t freehit;
  58        atomic_t freemiss;
  59
  60        /*
  61         * If debugging is enabled, then the allocator can add additional
  62         * fields and/or padding to every object. size contains the total
  63         * object size including these internal fields, the following two
  64         * variables contain the offset to the user object and its size.
  65         */
  66        int obj_offset;
  67#endif /* CONFIG_DEBUG_SLAB */
  68#ifdef CONFIG_MEMCG_KMEM
  69        struct memcg_cache_params *memcg_params;
  70#endif
  71
  72/* 6) per-cpu/per-node data, touched during every alloc/free */
  73        /*
  74         * We put array[] at the end of kmem_cache, because we want to size
  75         * this array to nr_cpu_ids slots instead of NR_CPUS
  76         * (see kmem_cache_init())
  77         * We still use [NR_CPUS] and not [1] or [0] because cache_cache
  78         * is statically defined, so we reserve the max number of cpus.
  79         *
  80         * We also need to guarantee that the list is able to accomodate a
  81         * pointer for each node since "nodelists" uses the remainder of
  82         * available pointers.
  83         */
  84        struct kmem_cache_node **node;
  85        struct array_cache *array[NR_CPUS + MAX_NUMNODES];
  86        /*
  87         * Do not add fields after array[]
  88         */
  89};
  90
  91#endif  /* _LINUX_SLAB_DEF_H */
  92