4 * Internal slab definitions
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.
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.
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 */
30 #endif /* CONFIG_SLOB */
33 #include <linux/slab_def.h>
37 #include <linux/slub_def.h>
40 #include <linux/memcontrol.h>
43 * State of the slab allocator.
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.
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 */
58 extern enum slab_state slab_state;
60 /* The slab cache mutex protects the management structures during changes */
61 extern struct mutex slab_mutex;
63 /* The list of all slab caches on the system */
64 extern struct list_head slab_caches;
66 /* The slab cache that manages slab cache information */
67 extern struct kmem_cache *kmem_cache;
69 unsigned long calculate_alignment(unsigned long flags,
70 unsigned long align, unsigned long size);
73 /* Kmalloc array related functions */
74 void create_kmalloc_caches(unsigned long);
76 /* Find the kmalloc slab corresponding for a certain size */
77 struct kmem_cache *kmalloc_slab(size_t, gfp_t);
81 /* Functions provided by the slab allocators */
82 extern int __kmem_cache_create(struct kmem_cache *, unsigned long flags);
84 extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size,
86 extern void create_boot_cache(struct kmem_cache *, const char *name,
87 size_t size, unsigned long flags);
89 int slab_unmergeable(struct kmem_cache *s);
90 struct kmem_cache *find_mergeable(size_t size, size_t align,
91 unsigned long flags, const char *name, void (*ctor)(void *));
94 __kmem_cache_alias(const char *name, size_t size, size_t align,
95 unsigned long flags, void (*ctor)(void *));
97 unsigned long kmem_cache_flags(unsigned long object_size,
98 unsigned long flags, const char *name,
99 void (*ctor)(void *));
101 static inline struct kmem_cache *
102 __kmem_cache_alias(const char *name, size_t size, size_t align,
103 unsigned long flags, void (*ctor)(void *))
106 static inline unsigned long kmem_cache_flags(unsigned long object_size,
107 unsigned long flags, const char *name,
108 void (*ctor)(void *))
115 /* Legal flag mask for kmem_cache_create(), for various configurations */
116 #define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | SLAB_PANIC | \
117 SLAB_DESTROY_BY_RCU | SLAB_DEBUG_OBJECTS )
119 #if defined(CONFIG_DEBUG_SLAB)
120 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
121 #elif defined(CONFIG_SLUB_DEBUG)
122 #define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
123 SLAB_TRACE | SLAB_DEBUG_FREE)
125 #define SLAB_DEBUG_FLAGS (0)
128 #if defined(CONFIG_SLAB)
129 #define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
130 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | SLAB_NOTRACK)
131 #elif defined(CONFIG_SLUB)
132 #define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
133 SLAB_TEMPORARY | SLAB_NOTRACK)
135 #define SLAB_CACHE_FLAGS (0)
138 #define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
140 int __kmem_cache_shutdown(struct kmem_cache *);
141 int __kmem_cache_shrink(struct kmem_cache *, bool);
142 void slab_kmem_cache_release(struct kmem_cache *);
148 unsigned long active_objs;
149 unsigned long num_objs;
150 unsigned long active_slabs;
151 unsigned long num_slabs;
152 unsigned long shared_avail;
154 unsigned int batchcount;
156 unsigned int objects_per_slab;
157 unsigned int cache_order;
160 void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
161 void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
162 ssize_t slabinfo_write(struct file *file, const char __user *buffer,
163 size_t count, loff_t *ppos);
166 * Generic implementation of bulk operations
167 * These are useful for situations in which the allocator cannot
168 * perform optimizations. In that case segments of the objecct listed
169 * may be allocated or freed using these operations.
171 void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
172 bool __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
174 #ifdef CONFIG_MEMCG_KMEM
176 * Iterate over all memcg caches of the given root cache. The caller must hold
179 #define for_each_memcg_cache(iter, root) \
180 list_for_each_entry(iter, &(root)->memcg_params.list, \
183 #define for_each_memcg_cache_safe(iter, tmp, root) \
184 list_for_each_entry_safe(iter, tmp, &(root)->memcg_params.list, \
187 static inline bool is_root_cache(struct kmem_cache *s)
189 return s->memcg_params.is_root_cache;
192 static inline bool slab_equal_or_root(struct kmem_cache *s,
193 struct kmem_cache *p)
195 return p == s || p == s->memcg_params.root_cache;
199 * We use suffixes to the name in memcg because we can't have caches
200 * created in the system with the same name. But when we print them
201 * locally, better refer to them with the base name
203 static inline const char *cache_name(struct kmem_cache *s)
205 if (!is_root_cache(s))
206 s = s->memcg_params.root_cache;
211 * Note, we protect with RCU only the memcg_caches array, not per-memcg caches.
212 * That said the caller must assure the memcg's cache won't go away by either
213 * taking a css reference to the owner cgroup, or holding the slab_mutex.
215 static inline struct kmem_cache *
216 cache_from_memcg_idx(struct kmem_cache *s, int idx)
218 struct kmem_cache *cachep;
219 struct memcg_cache_array *arr;
222 arr = rcu_dereference(s->memcg_params.memcg_caches);
225 * Make sure we will access the up-to-date value. The code updating
226 * memcg_caches issues a write barrier to match this (see
227 * memcg_create_kmem_cache()).
229 cachep = lockless_dereference(arr->entries[idx]);
235 static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
237 if (is_root_cache(s))
239 return s->memcg_params.root_cache;
242 static __always_inline int memcg_charge_slab(struct kmem_cache *s,
243 gfp_t gfp, int order)
245 if (!memcg_kmem_enabled())
247 if (is_root_cache(s))
249 return memcg_charge_kmem(s->memcg_params.memcg, gfp, 1 << order);
252 static __always_inline void memcg_uncharge_slab(struct kmem_cache *s, int order)
254 if (!memcg_kmem_enabled())
256 if (is_root_cache(s))
258 memcg_uncharge_kmem(s->memcg_params.memcg, 1 << order);
261 extern void slab_init_memcg_params(struct kmem_cache *);
263 #else /* !CONFIG_MEMCG_KMEM */
265 #define for_each_memcg_cache(iter, root) \
266 for ((void)(iter), (void)(root); 0; )
267 #define for_each_memcg_cache_safe(iter, tmp, root) \
268 for ((void)(iter), (void)(tmp), (void)(root); 0; )
270 static inline bool is_root_cache(struct kmem_cache *s)
275 static inline bool slab_equal_or_root(struct kmem_cache *s,
276 struct kmem_cache *p)
281 static inline const char *cache_name(struct kmem_cache *s)
286 static inline struct kmem_cache *
287 cache_from_memcg_idx(struct kmem_cache *s, int idx)
292 static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
297 static inline int memcg_charge_slab(struct kmem_cache *s, gfp_t gfp, int order)
302 static inline void memcg_uncharge_slab(struct kmem_cache *s, int order)
306 static inline void slab_init_memcg_params(struct kmem_cache *s)
309 #endif /* CONFIG_MEMCG_KMEM */
311 static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
313 struct kmem_cache *cachep;
317 * When kmemcg is not being used, both assignments should return the
318 * same value. but we don't want to pay the assignment price in that
319 * case. If it is not compiled in, the compiler should be smart enough
320 * to not do even the assignment. In that case, slab_equal_or_root
321 * will also be a constant.
323 if (!memcg_kmem_enabled() && !unlikely(s->flags & SLAB_DEBUG_FREE))
326 page = virt_to_head_page(x);
327 cachep = page->slab_cache;
328 if (slab_equal_or_root(cachep, s))
331 pr_err("%s: Wrong slab cache. %s but object is from %s\n",
332 __func__, cachep->name, s->name);
339 * The slab lists for all objects.
341 struct kmem_cache_node {
342 spinlock_t list_lock;
345 struct list_head slabs_partial; /* partial list first, better asm code */
346 struct list_head slabs_full;
347 struct list_head slabs_free;
348 unsigned long free_objects;
349 unsigned int free_limit;
350 unsigned int colour_next; /* Per-node cache coloring */
351 struct array_cache *shared; /* shared per node */
352 struct alien_cache **alien; /* on other nodes */
353 unsigned long next_reap; /* updated without locking */
354 int free_touched; /* updated without locking */
358 unsigned long nr_partial;
359 struct list_head partial;
360 #ifdef CONFIG_SLUB_DEBUG
361 atomic_long_t nr_slabs;
362 atomic_long_t total_objects;
363 struct list_head full;
369 static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
371 return s->node[node];
375 * Iterator over all nodes. The body will be executed for each node that has
376 * a kmem_cache_node structure allocated (which is true for all online nodes)
378 #define for_each_kmem_cache_node(__s, __node, __n) \
379 for (__node = 0; __node < nr_node_ids; __node++) \
380 if ((__n = get_node(__s, __node)))
384 void *slab_start(struct seq_file *m, loff_t *pos);
385 void *slab_next(struct seq_file *m, void *p, loff_t *pos);
386 void slab_stop(struct seq_file *m, void *p);
387 int memcg_slab_show(struct seq_file *m, void *p);
389 #endif /* MM_SLAB_H */