1 #ifndef MM_SLAB_H 2 #define MM_SLAB_H 3 /* 4 * Internal slab definitions 5 */ 6 7 /* 8 * State of the slab allocator. 9 * 10 * This is used to describe the states of the allocator during bootup. 11 * Allocators use this to gradually bootstrap themselves. Most allocators 12 * have the problem that the structures used for managing slab caches are 13 * allocated from slab caches themselves. 14 */ 15 enum slab_state { 16 DOWN, /* No slab functionality yet */ 17 PARTIAL, /* SLUB: kmem_cache_node available */ 18 PARTIAL_ARRAYCACHE, /* SLAB: kmalloc size for arraycache available */ 19 PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */ 20 UP, /* Slab caches usable but not all extras yet */ 21 FULL /* Everything is working */ 22 }; 23 24 extern enum slab_state slab_state; 25 26 /* The slab cache mutex protects the management structures during changes */ 27 extern struct mutex slab_mutex; 28 29 /* The list of all slab caches on the system */ 30 extern struct list_head slab_caches; 31 32 /* The slab cache that manages slab cache information */ 33 extern struct kmem_cache *kmem_cache; 34 35 unsigned long calculate_alignment(unsigned long flags, 36 unsigned long align, unsigned long size); 37 38 #ifndef CONFIG_SLOB 39 /* Kmalloc array related functions */ 40 void create_kmalloc_caches(unsigned long); 41 42 /* Find the kmalloc slab corresponding for a certain size */ 43 struct kmem_cache *kmalloc_slab(size_t, gfp_t); 44 #endif 45 46 47 /* Functions provided by the slab allocators */ 48 extern int __kmem_cache_create(struct kmem_cache *, unsigned long flags); 49 50 extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size, 51 unsigned long flags); 52 extern void create_boot_cache(struct kmem_cache *, const char *name, 53 size_t size, unsigned long flags); 54 55 struct mem_cgroup; 56 #ifdef CONFIG_SLUB 57 struct kmem_cache * 58 __kmem_cache_alias(struct mem_cgroup *memcg, const char *name, size_t size, 59 size_t align, unsigned long flags, void (*ctor)(void *)); 60 #else 61 static inline struct kmem_cache * 62 __kmem_cache_alias(struct mem_cgroup *memcg, const char *name, size_t size, 63 size_t align, unsigned long flags, void (*ctor)(void *)) 64 { return NULL; } 65 #endif 66 67 68 /* Legal flag mask for kmem_cache_create(), for various configurations */ 69 #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | SLAB_PANIC | \ 70 SLAB_DESTROY_BY_RCU | SLAB_DEBUG_OBJECTS ) 71 72 #if defined(CONFIG_DEBUG_SLAB) 73 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) 74 #elif defined(CONFIG_SLUB_DEBUG) 75 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ 76 SLAB_TRACE | SLAB_DEBUG_FREE) 77 #else 78 #define SLAB_DEBUG_FLAGS (0) 79 #endif 80 81 #if defined(CONFIG_SLAB) 82 #define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \ 83 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | SLAB_NOTRACK) 84 #elif defined(CONFIG_SLUB) 85 #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ 86 SLAB_TEMPORARY | SLAB_NOTRACK) 87 #else 88 #define SLAB_CACHE_FLAGS (0) 89 #endif 90 91 #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) 92 93 int __kmem_cache_shutdown(struct kmem_cache *); 94 95 struct seq_file; 96 struct file; 97 98 struct slabinfo { 99 unsigned long active_objs; 100 unsigned long num_objs; 101 unsigned long active_slabs; 102 unsigned long num_slabs; 103 unsigned long shared_avail; 104 unsigned int limit; 105 unsigned int batchcount; 106 unsigned int shared; 107 unsigned int objects_per_slab; 108 unsigned int cache_order; 109 }; 110 111 void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo); 112 void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s); 113 ssize_t slabinfo_write(struct file *file, const char __user *buffer, 114 size_t count, loff_t *ppos); 115 116 #ifdef CONFIG_MEMCG_KMEM 117 static inline bool is_root_cache(struct kmem_cache *s) 118 { 119 return !s->memcg_params || s->memcg_params->is_root_cache; 120 } 121 122 static inline bool cache_match_memcg(struct kmem_cache *cachep, 123 struct mem_cgroup *memcg) 124 { 125 return (is_root_cache(cachep) && !memcg) || 126 (cachep->memcg_params->memcg == memcg); 127 } 128 129 static inline void memcg_bind_pages(struct kmem_cache *s, int order) 130 { 131 if (!is_root_cache(s)) 132 atomic_add(1 << order, &s->memcg_params->nr_pages); 133 } 134 135 static inline void memcg_release_pages(struct kmem_cache *s, int order) 136 { 137 if (is_root_cache(s)) 138 return; 139 140 if (atomic_sub_and_test((1 << order), &s->memcg_params->nr_pages)) 141 mem_cgroup_destroy_cache(s); 142 } 143 144 static inline bool slab_equal_or_root(struct kmem_cache *s, 145 struct kmem_cache *p) 146 { 147 return (p == s) || 148 (s->memcg_params && (p == s->memcg_params->root_cache)); 149 } 150 151 /* 152 * We use suffixes to the name in memcg because we can't have caches 153 * created in the system with the same name. But when we print them 154 * locally, better refer to them with the base name 155 */ 156 static inline const char *cache_name(struct kmem_cache *s) 157 { 158 if (!is_root_cache(s)) 159 return s->memcg_params->root_cache->name; 160 return s->name; 161 } 162 163 static inline struct kmem_cache *cache_from_memcg(struct kmem_cache *s, int idx) 164 { 165 return s->memcg_params->memcg_caches[idx]; 166 } 167 168 static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s) 169 { 170 if (is_root_cache(s)) 171 return s; 172 return s->memcg_params->root_cache; 173 } 174 #else 175 static inline bool is_root_cache(struct kmem_cache *s) 176 { 177 return true; 178 } 179 180 static inline bool cache_match_memcg(struct kmem_cache *cachep, 181 struct mem_cgroup *memcg) 182 { 183 return true; 184 } 185 186 static inline void memcg_bind_pages(struct kmem_cache *s, int order) 187 { 188 } 189 190 static inline void memcg_release_pages(struct kmem_cache *s, int order) 191 { 192 } 193 194 static inline bool slab_equal_or_root(struct kmem_cache *s, 195 struct kmem_cache *p) 196 { 197 return true; 198 } 199 200 static inline const char *cache_name(struct kmem_cache *s) 201 { 202 return s->name; 203 } 204 205 static inline struct kmem_cache *cache_from_memcg(struct kmem_cache *s, int idx) 206 { 207 return NULL; 208 } 209 210 static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s) 211 { 212 return s; 213 } 214 #endif 215 216 static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) 217 { 218 struct kmem_cache *cachep; 219 struct page *page; 220 221 /* 222 * When kmemcg is not being used, both assignments should return the 223 * same value. but we don't want to pay the assignment price in that 224 * case. If it is not compiled in, the compiler should be smart enough 225 * to not do even the assignment. In that case, slab_equal_or_root 226 * will also be a constant. 227 */ 228 if (!memcg_kmem_enabled() && !unlikely(s->flags & SLAB_DEBUG_FREE)) 229 return s; 230 231 page = virt_to_head_page(x); 232 cachep = page->slab_cache; 233 if (slab_equal_or_root(cachep, s)) 234 return cachep; 235 236 pr_err("%s: Wrong slab cache. %s but object is from %s\n", 237 __FUNCTION__, cachep->name, s->name); 238 WARN_ON_ONCE(1); 239 return s; 240 } 241 #endif 242 243 244 /* 245 * The slab lists for all objects. 246 */ 247 struct kmem_cache_node { 248 spinlock_t list_lock; 249 250 #ifdef CONFIG_SLAB 251 struct list_head slabs_partial; /* partial list first, better asm code */ 252 struct list_head slabs_full; 253 struct list_head slabs_free; 254 unsigned long free_objects; 255 unsigned int free_limit; 256 unsigned int colour_next; /* Per-node cache coloring */ 257 struct array_cache *shared; /* shared per node */ 258 struct array_cache **alien; /* on other nodes */ 259 unsigned long next_reap; /* updated without locking */ 260 int free_touched; /* updated without locking */ 261 #endif 262 263 #ifdef CONFIG_SLUB 264 unsigned long nr_partial; 265 struct list_head partial; 266 #ifdef CONFIG_SLUB_DEBUG 267 atomic_long_t nr_slabs; 268 atomic_long_t total_objects; 269 struct list_head full; 270 #endif 271 #endif 272 273 }; 274 275 void *slab_next(struct seq_file *m, void *p, loff_t *pos); 276 void slab_stop(struct seq_file *m, void *p); 277