1 #ifndef MM_SLAB_H 2 #define MM_SLAB_H 3 /* 4 * Internal slab definitions 5 */ 6 7 #ifdef CONFIG_SLOB 8 /* 9 * Common fields provided in kmem_cache by all slab allocators 10 * This struct is either used directly by the allocator (SLOB) 11 * or the allocator must include definitions for all fields 12 * provided in kmem_cache_common in their definition of kmem_cache. 13 * 14 * Once we can do anonymous structs (C11 standard) we could put a 15 * anonymous struct definition in these allocators so that the 16 * separate allocations in the kmem_cache structure of SLAB and 17 * SLUB is no longer needed. 18 */ 19 struct kmem_cache { 20 unsigned int object_size;/* The original size of the object */ 21 unsigned int size; /* The aligned/padded/added on size */ 22 unsigned int align; /* Alignment as calculated */ 23 unsigned long flags; /* Active flags on the slab */ 24 const char *name; /* Slab name for sysfs */ 25 int refcount; /* Use counter */ 26 void (*ctor)(void *); /* Called on object slot creation */ 27 struct list_head list; /* List of all slab caches on the system */ 28 }; 29 30 #endif /* CONFIG_SLOB */ 31 32 #ifdef CONFIG_SLAB 33 #include <linux/slab_def.h> 34 #endif 35 36 #ifdef CONFIG_SLUB 37 #include <linux/slub_def.h> 38 #endif 39 40 #include <linux/memcontrol.h> 41 42 /* 43 * State of the slab allocator. 44 * 45 * This is used to describe the states of the allocator during bootup. 46 * Allocators use this to gradually bootstrap themselves. Most allocators 47 * have the problem that the structures used for managing slab caches are 48 * allocated from slab caches themselves. 49 */ 50 enum slab_state { 51 DOWN, /* No slab functionality yet */ 52 PARTIAL, /* SLUB: kmem_cache_node available */ 53 PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */ 54 UP, /* Slab caches usable but not all extras yet */ 55 FULL /* Everything is working */ 56 }; 57 58 extern enum slab_state slab_state; 59 60 /* The slab cache mutex protects the management structures during changes */ 61 extern struct mutex slab_mutex; 62 63 /* The list of all slab caches on the system */ 64 extern struct list_head slab_caches; 65 66 /* The slab cache that manages slab cache information */ 67 extern struct kmem_cache *kmem_cache; 68 69 unsigned long calculate_alignment(unsigned long flags, 70 unsigned long align, unsigned long size); 71 72 #ifndef CONFIG_SLOB 73 /* Kmalloc array related functions */ 74 void setup_kmalloc_cache_index_table(void); 75 void create_kmalloc_caches(unsigned long); 76 77 /* Find the kmalloc slab corresponding for a certain size */ 78 struct kmem_cache *kmalloc_slab(size_t, gfp_t); 79 #endif 80 81 82 /* Functions provided by the slab allocators */ 83 extern int __kmem_cache_create(struct kmem_cache *, unsigned long flags); 84 85 extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size, 86 unsigned long flags); 87 extern void create_boot_cache(struct kmem_cache *, const char *name, 88 size_t size, unsigned long flags); 89 90 int slab_unmergeable(struct kmem_cache *s); 91 struct kmem_cache *find_mergeable(size_t size, size_t align, 92 unsigned long flags, const char *name, void (*ctor)(void *)); 93 #ifndef CONFIG_SLOB 94 struct kmem_cache * 95 __kmem_cache_alias(const char *name, size_t size, size_t align, 96 unsigned long flags, void (*ctor)(void *)); 97 98 unsigned long kmem_cache_flags(unsigned long object_size, 99 unsigned long flags, const char *name, 100 void (*ctor)(void *)); 101 #else 102 static inline struct kmem_cache * 103 __kmem_cache_alias(const char *name, size_t size, size_t align, 104 unsigned long flags, void (*ctor)(void *)) 105 { return NULL; } 106 107 static inline unsigned long kmem_cache_flags(unsigned long object_size, 108 unsigned long flags, const char *name, 109 void (*ctor)(void *)) 110 { 111 return flags; 112 } 113 #endif 114 115 116 /* Legal flag mask for kmem_cache_create(), for various configurations */ 117 #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | SLAB_PANIC | \ 118 SLAB_DESTROY_BY_RCU | SLAB_DEBUG_OBJECTS ) 119 120 #if defined(CONFIG_DEBUG_SLAB) 121 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER) 122 #elif defined(CONFIG_SLUB_DEBUG) 123 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \ 124 SLAB_TRACE | SLAB_DEBUG_FREE) 125 #else 126 #define SLAB_DEBUG_FLAGS (0) 127 #endif 128 129 #if defined(CONFIG_SLAB) 130 #define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \ 131 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | SLAB_NOTRACK) 132 #elif defined(CONFIG_SLUB) 133 #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \ 134 SLAB_TEMPORARY | SLAB_NOTRACK) 135 #else 136 #define SLAB_CACHE_FLAGS (0) 137 #endif 138 139 #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS) 140 141 int __kmem_cache_shutdown(struct kmem_cache *); 142 int __kmem_cache_shrink(struct kmem_cache *, bool); 143 void slab_kmem_cache_release(struct kmem_cache *); 144 145 struct seq_file; 146 struct file; 147 148 struct slabinfo { 149 unsigned long active_objs; 150 unsigned long num_objs; 151 unsigned long active_slabs; 152 unsigned long num_slabs; 153 unsigned long shared_avail; 154 unsigned int limit; 155 unsigned int batchcount; 156 unsigned int shared; 157 unsigned int objects_per_slab; 158 unsigned int cache_order; 159 }; 160 161 void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo); 162 void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s); 163 ssize_t slabinfo_write(struct file *file, const char __user *buffer, 164 size_t count, loff_t *ppos); 165 166 /* 167 * Generic implementation of bulk operations 168 * These are useful for situations in which the allocator cannot 169 * perform optimizations. In that case segments of the objecct listed 170 * may be allocated or freed using these operations. 171 */ 172 void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **); 173 int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **); 174 175 #ifdef CONFIG_MEMCG_KMEM 176 /* 177 * Iterate over all memcg caches of the given root cache. The caller must hold 178 * slab_mutex. 179 */ 180 #define for_each_memcg_cache(iter, root) \ 181 list_for_each_entry(iter, &(root)->memcg_params.list, \ 182 memcg_params.list) 183 184 static inline bool is_root_cache(struct kmem_cache *s) 185 { 186 return s->memcg_params.is_root_cache; 187 } 188 189 static inline bool slab_equal_or_root(struct kmem_cache *s, 190 struct kmem_cache *p) 191 { 192 return p == s || p == s->memcg_params.root_cache; 193 } 194 195 /* 196 * We use suffixes to the name in memcg because we can't have caches 197 * created in the system with the same name. But when we print them 198 * locally, better refer to them with the base name 199 */ 200 static inline const char *cache_name(struct kmem_cache *s) 201 { 202 if (!is_root_cache(s)) 203 s = s->memcg_params.root_cache; 204 return s->name; 205 } 206 207 /* 208 * Note, we protect with RCU only the memcg_caches array, not per-memcg caches. 209 * That said the caller must assure the memcg's cache won't go away by either 210 * taking a css reference to the owner cgroup, or holding the slab_mutex. 211 */ 212 static inline struct kmem_cache * 213 cache_from_memcg_idx(struct kmem_cache *s, int idx) 214 { 215 struct kmem_cache *cachep; 216 struct memcg_cache_array *arr; 217 218 rcu_read_lock(); 219 arr = rcu_dereference(s->memcg_params.memcg_caches); 220 221 /* 222 * Make sure we will access the up-to-date value. The code updating 223 * memcg_caches issues a write barrier to match this (see 224 * memcg_create_kmem_cache()). 225 */ 226 cachep = lockless_dereference(arr->entries[idx]); 227 rcu_read_unlock(); 228 229 return cachep; 230 } 231 232 static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s) 233 { 234 if (is_root_cache(s)) 235 return s; 236 return s->memcg_params.root_cache; 237 } 238 239 static __always_inline int memcg_charge_slab(struct page *page, 240 gfp_t gfp, int order, 241 struct kmem_cache *s) 242 { 243 if (!memcg_kmem_enabled()) 244 return 0; 245 if (is_root_cache(s)) 246 return 0; 247 return __memcg_kmem_charge_memcg(page, gfp, order, 248 s->memcg_params.memcg); 249 } 250 251 extern void slab_init_memcg_params(struct kmem_cache *); 252 253 #else /* !CONFIG_MEMCG_KMEM */ 254 255 #define for_each_memcg_cache(iter, root) \ 256 for ((void)(iter), (void)(root); 0; ) 257 258 static inline bool is_root_cache(struct kmem_cache *s) 259 { 260 return true; 261 } 262 263 static inline bool slab_equal_or_root(struct kmem_cache *s, 264 struct kmem_cache *p) 265 { 266 return true; 267 } 268 269 static inline const char *cache_name(struct kmem_cache *s) 270 { 271 return s->name; 272 } 273 274 static inline struct kmem_cache * 275 cache_from_memcg_idx(struct kmem_cache *s, int idx) 276 { 277 return NULL; 278 } 279 280 static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s) 281 { 282 return s; 283 } 284 285 static inline int memcg_charge_slab(struct page *page, gfp_t gfp, int order, 286 struct kmem_cache *s) 287 { 288 return 0; 289 } 290 291 static inline void slab_init_memcg_params(struct kmem_cache *s) 292 { 293 } 294 #endif /* CONFIG_MEMCG_KMEM */ 295 296 static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x) 297 { 298 struct kmem_cache *cachep; 299 struct page *page; 300 301 /* 302 * When kmemcg is not being used, both assignments should return the 303 * same value. but we don't want to pay the assignment price in that 304 * case. If it is not compiled in, the compiler should be smart enough 305 * to not do even the assignment. In that case, slab_equal_or_root 306 * will also be a constant. 307 */ 308 if (!memcg_kmem_enabled() && !unlikely(s->flags & SLAB_DEBUG_FREE)) 309 return s; 310 311 page = virt_to_head_page(x); 312 cachep = page->slab_cache; 313 if (slab_equal_or_root(cachep, s)) 314 return cachep; 315 316 pr_err("%s: Wrong slab cache. %s but object is from %s\n", 317 __func__, s->name, cachep->name); 318 WARN_ON_ONCE(1); 319 return s; 320 } 321 322 #ifndef CONFIG_SLOB 323 /* 324 * The slab lists for all objects. 325 */ 326 struct kmem_cache_node { 327 spinlock_t list_lock; 328 329 #ifdef CONFIG_SLAB 330 struct list_head slabs_partial; /* partial list first, better asm code */ 331 struct list_head slabs_full; 332 struct list_head slabs_free; 333 unsigned long free_objects; 334 unsigned int free_limit; 335 unsigned int colour_next; /* Per-node cache coloring */ 336 struct array_cache *shared; /* shared per node */ 337 struct alien_cache **alien; /* on other nodes */ 338 unsigned long next_reap; /* updated without locking */ 339 int free_touched; /* updated without locking */ 340 #endif 341 342 #ifdef CONFIG_SLUB 343 unsigned long nr_partial; 344 struct list_head partial; 345 #ifdef CONFIG_SLUB_DEBUG 346 atomic_long_t nr_slabs; 347 atomic_long_t total_objects; 348 struct list_head full; 349 #endif 350 #endif 351 352 }; 353 354 static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node) 355 { 356 return s->node[node]; 357 } 358 359 /* 360 * Iterator over all nodes. The body will be executed for each node that has 361 * a kmem_cache_node structure allocated (which is true for all online nodes) 362 */ 363 #define for_each_kmem_cache_node(__s, __node, __n) \ 364 for (__node = 0; __node < nr_node_ids; __node++) \ 365 if ((__n = get_node(__s, __node))) 366 367 #endif 368 369 void *slab_start(struct seq_file *m, loff_t *pos); 370 void *slab_next(struct seq_file *m, void *p, loff_t *pos); 371 void slab_stop(struct seq_file *m, void *p); 372 int memcg_slab_show(struct seq_file *m, void *p); 373 374 #endif /* MM_SLAB_H */ 375