| 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 | * What we provide here is a way to optimize the frequent kmalloc |
| 8 | * calls in the kernel by selecting the appropriate general cache |
| 9 | * if kmalloc was called with a size that can be established at |
| 10 | * compile time. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/init.h> |
| 14 | #include <linux/compiler.h> |
| 15 | |
| 16 | /* |
| 17 | * struct kmem_cache |
| 18 | * |
| 19 | * manages a cache. |
| 20 | */ |
| 21 | |
| 22 | struct kmem_cache { |
| 23 | /* 1) Cache tunables. Protected by cache_chain_mutex */ |
| 24 | unsigned int batchcount; |
| 25 | unsigned int limit; |
| 26 | unsigned int shared; |
| 27 | |
| 28 | unsigned int size; |
| 29 | u32 reciprocal_buffer_size; |
| 30 | /* 2) touched by every alloc & free from the backend */ |
| 31 | |
| 32 | unsigned int flags; /* constant flags */ |
| 33 | unsigned int num; /* # of objs per slab */ |
| 34 | |
| 35 | /* 3) cache_grow/shrink */ |
| 36 | /* order of pgs per slab (2^n) */ |
| 37 | unsigned int gfporder; |
| 38 | |
| 39 | /* force GFP flags, e.g. GFP_DMA */ |
| 40 | gfp_t allocflags; |
| 41 | |
| 42 | size_t colour; /* cache colouring range */ |
| 43 | unsigned int colour_off; /* colour offset */ |
| 44 | struct kmem_cache *slabp_cache; |
| 45 | unsigned int slab_size; |
| 46 | |
| 47 | /* constructor func */ |
| 48 | void (*ctor)(void *obj); |
| 49 | |
| 50 | /* 4) cache creation/removal */ |
| 51 | const char *name; |
| 52 | struct list_head list; |
| 53 | int refcount; |
| 54 | int object_size; |
| 55 | int align; |
| 56 | |
| 57 | /* 5) statistics */ |
| 58 | #ifdef CONFIG_DEBUG_SLAB |
| 59 | unsigned long num_active; |
| 60 | unsigned long num_allocations; |
| 61 | unsigned long high_mark; |
| 62 | unsigned long grown; |
| 63 | unsigned long reaped; |
| 64 | unsigned long errors; |
| 65 | unsigned long max_freeable; |
| 66 | unsigned long node_allocs; |
| 67 | unsigned long node_frees; |
| 68 | unsigned long node_overflow; |
| 69 | atomic_t allochit; |
| 70 | atomic_t allocmiss; |
| 71 | atomic_t freehit; |
| 72 | atomic_t freemiss; |
| 73 | |
| 74 | /* |
| 75 | * If debugging is enabled, then the allocator can add additional |
| 76 | * fields and/or padding to every object. size contains the total |
| 77 | * object size including these internal fields, the following two |
| 78 | * variables contain the offset to the user object and its size. |
| 79 | */ |
| 80 | int obj_offset; |
| 81 | #endif /* CONFIG_DEBUG_SLAB */ |
| 82 | #ifdef CONFIG_MEMCG_KMEM |
| 83 | struct memcg_cache_params *memcg_params; |
| 84 | #endif |
| 85 | |
| 86 | /* 6) per-cpu/per-node data, touched during every alloc/free */ |
| 87 | /* |
| 88 | * We put array[] at the end of kmem_cache, because we want to size |
| 89 | * this array to nr_cpu_ids slots instead of NR_CPUS |
| 90 | * (see kmem_cache_init()) |
| 91 | * We still use [NR_CPUS] and not [1] or [0] because cache_cache |
| 92 | * is statically defined, so we reserve the max number of cpus. |
| 93 | * |
| 94 | * We also need to guarantee that the list is able to accomodate a |
| 95 | * pointer for each node since "nodelists" uses the remainder of |
| 96 | * available pointers. |
| 97 | */ |
| 98 | struct kmem_cache_node **node; |
| 99 | struct array_cache *array[NR_CPUS + MAX_NUMNODES]; |
| 100 | /* |
| 101 | * Do not add fields after array[] |
| 102 | */ |
| 103 | }; |
| 104 | |
| 105 | void *kmem_cache_alloc(struct kmem_cache *, gfp_t); |
| 106 | void *__kmalloc(size_t size, gfp_t flags); |
| 107 | |
| 108 | #ifdef CONFIG_TRACING |
| 109 | extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t); |
| 110 | #else |
| 111 | static __always_inline void * |
| 112 | kmem_cache_alloc_trace(struct kmem_cache *cachep, gfp_t flags, size_t size) |
| 113 | { |
| 114 | return kmem_cache_alloc(cachep, flags); |
| 115 | } |
| 116 | #endif |
| 117 | |
| 118 | static __always_inline void *kmalloc(size_t size, gfp_t flags) |
| 119 | { |
| 120 | struct kmem_cache *cachep; |
| 121 | void *ret; |
| 122 | |
| 123 | if (__builtin_constant_p(size)) { |
| 124 | int i; |
| 125 | |
| 126 | if (!size) |
| 127 | return ZERO_SIZE_PTR; |
| 128 | |
| 129 | if (WARN_ON_ONCE(size > KMALLOC_MAX_SIZE)) |
| 130 | return NULL; |
| 131 | |
| 132 | i = kmalloc_index(size); |
| 133 | |
| 134 | #ifdef CONFIG_ZONE_DMA |
| 135 | if (flags & GFP_DMA) |
| 136 | cachep = kmalloc_dma_caches[i]; |
| 137 | else |
| 138 | #endif |
| 139 | cachep = kmalloc_caches[i]; |
| 140 | |
| 141 | ret = kmem_cache_alloc_trace(cachep, flags, size); |
| 142 | |
| 143 | return ret; |
| 144 | } |
| 145 | return __kmalloc(size, flags); |
| 146 | } |
| 147 | |
| 148 | #ifdef CONFIG_NUMA |
| 149 | extern void *__kmalloc_node(size_t size, gfp_t flags, int node); |
| 150 | extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node); |
| 151 | |
| 152 | #ifdef CONFIG_TRACING |
| 153 | extern void *kmem_cache_alloc_node_trace(struct kmem_cache *cachep, |
| 154 | gfp_t flags, |
| 155 | int nodeid, |
| 156 | size_t size); |
| 157 | #else |
| 158 | static __always_inline void * |
| 159 | kmem_cache_alloc_node_trace(struct kmem_cache *cachep, |
| 160 | gfp_t flags, |
| 161 | int nodeid, |
| 162 | size_t size) |
| 163 | { |
| 164 | return kmem_cache_alloc_node(cachep, flags, nodeid); |
| 165 | } |
| 166 | #endif |
| 167 | |
| 168 | static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node) |
| 169 | { |
| 170 | struct kmem_cache *cachep; |
| 171 | |
| 172 | if (__builtin_constant_p(size)) { |
| 173 | int i; |
| 174 | |
| 175 | if (!size) |
| 176 | return ZERO_SIZE_PTR; |
| 177 | |
| 178 | if (WARN_ON_ONCE(size > KMALLOC_MAX_SIZE)) |
| 179 | return NULL; |
| 180 | |
| 181 | i = kmalloc_index(size); |
| 182 | |
| 183 | #ifdef CONFIG_ZONE_DMA |
| 184 | if (flags & GFP_DMA) |
| 185 | cachep = kmalloc_dma_caches[i]; |
| 186 | else |
| 187 | #endif |
| 188 | cachep = kmalloc_caches[i]; |
| 189 | |
| 190 | return kmem_cache_alloc_node_trace(cachep, flags, node, size); |
| 191 | } |
| 192 | return __kmalloc_node(size, flags, node); |
| 193 | } |
| 194 | |
| 195 | #endif /* CONFIG_NUMA */ |
| 196 | |
| 197 | #endif /* _LINUX_SLAB_DEF_H */ |