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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 */
19struct 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#include <linux/fault-inject.h>
42#include <linux/kmemcheck.h>
43#include <linux/kasan.h>
44#include <linux/kmemleak.h>
45#include <linux/random.h>
46
47/*
48 * State of the slab allocator.
49 *
50 * This is used to describe the states of the allocator during bootup.
51 * Allocators use this to gradually bootstrap themselves. Most allocators
52 * have the problem that the structures used for managing slab caches are
53 * allocated from slab caches themselves.
54 */
55enum slab_state {
56 DOWN, /* No slab functionality yet */
57 PARTIAL, /* SLUB: kmem_cache_node available */
58 PARTIAL_NODE, /* SLAB: kmalloc size for node struct available */
59 UP, /* Slab caches usable but not all extras yet */
60 FULL /* Everything is working */
61};
62
63extern enum slab_state slab_state;
64
65/* The slab cache mutex protects the management structures during changes */
66extern struct mutex slab_mutex;
67
68/* The list of all slab caches on the system */
69extern struct list_head slab_caches;
70
71/* The slab cache that manages slab cache information */
72extern struct kmem_cache *kmem_cache;
73
74unsigned long calculate_alignment(unsigned long flags,
75 unsigned long align, unsigned long size);
76
77#ifndef CONFIG_SLOB
78/* Kmalloc array related functions */
79void setup_kmalloc_cache_index_table(void);
80void create_kmalloc_caches(unsigned long);
81
82/* Find the kmalloc slab corresponding for a certain size */
83struct kmem_cache *kmalloc_slab(size_t, gfp_t);
84#endif
85
86
87/* Functions provided by the slab allocators */
88extern int __kmem_cache_create(struct kmem_cache *, unsigned long flags);
89
90extern struct kmem_cache *create_kmalloc_cache(const char *name, size_t size,
91 unsigned long flags);
92extern void create_boot_cache(struct kmem_cache *, const char *name,
93 size_t size, unsigned long flags);
94
95int slab_unmergeable(struct kmem_cache *s);
96struct kmem_cache *find_mergeable(size_t size, size_t align,
97 unsigned long flags, const char *name, void (*ctor)(void *));
98#ifndef CONFIG_SLOB
99struct kmem_cache *
100__kmem_cache_alias(const char *name, size_t size, size_t align,
101 unsigned long flags, void (*ctor)(void *));
102
103unsigned long kmem_cache_flags(unsigned long object_size,
104 unsigned long flags, const char *name,
105 void (*ctor)(void *));
106#else
107static inline struct kmem_cache *
108__kmem_cache_alias(const char *name, size_t size, size_t align,
109 unsigned long flags, void (*ctor)(void *))
110{ return NULL; }
111
112static inline unsigned long kmem_cache_flags(unsigned long object_size,
113 unsigned long flags, const char *name,
114 void (*ctor)(void *))
115{
116 return flags;
117}
118#endif
119
120
121/* Legal flag mask for kmem_cache_create(), for various configurations */
122#define SLAB_CORE_FLAGS (SLAB_HWCACHE_ALIGN | SLAB_CACHE_DMA | SLAB_PANIC | \
123 SLAB_DESTROY_BY_RCU | SLAB_DEBUG_OBJECTS )
124
125#if defined(CONFIG_DEBUG_SLAB)
126#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER)
127#elif defined(CONFIG_SLUB_DEBUG)
128#define SLAB_DEBUG_FLAGS (SLAB_RED_ZONE | SLAB_POISON | SLAB_STORE_USER | \
129 SLAB_TRACE | SLAB_CONSISTENCY_CHECKS)
130#else
131#define SLAB_DEBUG_FLAGS (0)
132#endif
133
134#if defined(CONFIG_SLAB)
135#define SLAB_CACHE_FLAGS (SLAB_MEM_SPREAD | SLAB_NOLEAKTRACE | \
136 SLAB_RECLAIM_ACCOUNT | SLAB_TEMPORARY | \
137 SLAB_NOTRACK | SLAB_ACCOUNT)
138#elif defined(CONFIG_SLUB)
139#define SLAB_CACHE_FLAGS (SLAB_NOLEAKTRACE | SLAB_RECLAIM_ACCOUNT | \
140 SLAB_TEMPORARY | SLAB_NOTRACK | SLAB_ACCOUNT)
141#else
142#define SLAB_CACHE_FLAGS (0)
143#endif
144
145#define CACHE_CREATE_MASK (SLAB_CORE_FLAGS | SLAB_DEBUG_FLAGS | SLAB_CACHE_FLAGS)
146
147int __kmem_cache_shutdown(struct kmem_cache *);
148void __kmem_cache_release(struct kmem_cache *);
149int __kmem_cache_shrink(struct kmem_cache *);
150void slab_kmem_cache_release(struct kmem_cache *);
151
152struct seq_file;
153struct file;
154
155struct slabinfo {
156 unsigned long active_objs;
157 unsigned long num_objs;
158 unsigned long active_slabs;
159 unsigned long num_slabs;
160 unsigned long shared_avail;
161 unsigned int limit;
162 unsigned int batchcount;
163 unsigned int shared;
164 unsigned int objects_per_slab;
165 unsigned int cache_order;
166};
167
168void get_slabinfo(struct kmem_cache *s, struct slabinfo *sinfo);
169void slabinfo_show_stats(struct seq_file *m, struct kmem_cache *s);
170ssize_t slabinfo_write(struct file *file, const char __user *buffer,
171 size_t count, loff_t *ppos);
172
173/*
174 * Generic implementation of bulk operations
175 * These are useful for situations in which the allocator cannot
176 * perform optimizations. In that case segments of the object listed
177 * may be allocated or freed using these operations.
178 */
179void __kmem_cache_free_bulk(struct kmem_cache *, size_t, void **);
180int __kmem_cache_alloc_bulk(struct kmem_cache *, gfp_t, size_t, void **);
181
182#if defined(CONFIG_MEMCG) && !defined(CONFIG_SLOB)
183/*
184 * Iterate over all memcg caches of the given root cache. The caller must hold
185 * slab_mutex.
186 */
187#define for_each_memcg_cache(iter, root) \
188 list_for_each_entry(iter, &(root)->memcg_params.list, \
189 memcg_params.list)
190
191static inline bool is_root_cache(struct kmem_cache *s)
192{
193 return s->memcg_params.is_root_cache;
194}
195
196static inline bool slab_equal_or_root(struct kmem_cache *s,
197 struct kmem_cache *p)
198{
199 return p == s || p == s->memcg_params.root_cache;
200}
201
202/*
203 * We use suffixes to the name in memcg because we can't have caches
204 * created in the system with the same name. But when we print them
205 * locally, better refer to them with the base name
206 */
207static inline const char *cache_name(struct kmem_cache *s)
208{
209 if (!is_root_cache(s))
210 s = s->memcg_params.root_cache;
211 return s->name;
212}
213
214/*
215 * Note, we protect with RCU only the memcg_caches array, not per-memcg caches.
216 * That said the caller must assure the memcg's cache won't go away by either
217 * taking a css reference to the owner cgroup, or holding the slab_mutex.
218 */
219static inline struct kmem_cache *
220cache_from_memcg_idx(struct kmem_cache *s, int idx)
221{
222 struct kmem_cache *cachep;
223 struct memcg_cache_array *arr;
224
225 rcu_read_lock();
226 arr = rcu_dereference(s->memcg_params.memcg_caches);
227
228 /*
229 * Make sure we will access the up-to-date value. The code updating
230 * memcg_caches issues a write barrier to match this (see
231 * memcg_create_kmem_cache()).
232 */
233 cachep = lockless_dereference(arr->entries[idx]);
234 rcu_read_unlock();
235
236 return cachep;
237}
238
239static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
240{
241 if (is_root_cache(s))
242 return s;
243 return s->memcg_params.root_cache;
244}
245
246static __always_inline int memcg_charge_slab(struct page *page,
247 gfp_t gfp, int order,
248 struct kmem_cache *s)
249{
250 int ret;
251
252 if (!memcg_kmem_enabled())
253 return 0;
254 if (is_root_cache(s))
255 return 0;
256
257 ret = memcg_kmem_charge_memcg(page, gfp, order, s->memcg_params.memcg);
258 if (ret)
259 return ret;
260
261 memcg_kmem_update_page_stat(page,
262 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
263 MEMCG_SLAB_RECLAIMABLE : MEMCG_SLAB_UNRECLAIMABLE,
264 1 << order);
265 return 0;
266}
267
268static __always_inline void memcg_uncharge_slab(struct page *page, int order,
269 struct kmem_cache *s)
270{
271 if (!memcg_kmem_enabled())
272 return;
273
274 memcg_kmem_update_page_stat(page,
275 (s->flags & SLAB_RECLAIM_ACCOUNT) ?
276 MEMCG_SLAB_RECLAIMABLE : MEMCG_SLAB_UNRECLAIMABLE,
277 -(1 << order));
278 memcg_kmem_uncharge(page, order);
279}
280
281extern void slab_init_memcg_params(struct kmem_cache *);
282
283#else /* CONFIG_MEMCG && !CONFIG_SLOB */
284
285#define for_each_memcg_cache(iter, root) \
286 for ((void)(iter), (void)(root); 0; )
287
288static inline bool is_root_cache(struct kmem_cache *s)
289{
290 return true;
291}
292
293static inline bool slab_equal_or_root(struct kmem_cache *s,
294 struct kmem_cache *p)
295{
296 return true;
297}
298
299static inline const char *cache_name(struct kmem_cache *s)
300{
301 return s->name;
302}
303
304static inline struct kmem_cache *
305cache_from_memcg_idx(struct kmem_cache *s, int idx)
306{
307 return NULL;
308}
309
310static inline struct kmem_cache *memcg_root_cache(struct kmem_cache *s)
311{
312 return s;
313}
314
315static inline int memcg_charge_slab(struct page *page, gfp_t gfp, int order,
316 struct kmem_cache *s)
317{
318 return 0;
319}
320
321static inline void memcg_uncharge_slab(struct page *page, int order,
322 struct kmem_cache *s)
323{
324}
325
326static inline void slab_init_memcg_params(struct kmem_cache *s)
327{
328}
329#endif /* CONFIG_MEMCG && !CONFIG_SLOB */
330
331static inline struct kmem_cache *cache_from_obj(struct kmem_cache *s, void *x)
332{
333 struct kmem_cache *cachep;
334 struct page *page;
335
336 /*
337 * When kmemcg is not being used, both assignments should return the
338 * same value. but we don't want to pay the assignment price in that
339 * case. If it is not compiled in, the compiler should be smart enough
340 * to not do even the assignment. In that case, slab_equal_or_root
341 * will also be a constant.
342 */
343 if (!memcg_kmem_enabled() &&
344 !unlikely(s->flags & SLAB_CONSISTENCY_CHECKS))
345 return s;
346
347 page = virt_to_head_page(x);
348 cachep = page->slab_cache;
349 if (slab_equal_or_root(cachep, s))
350 return cachep;
351
352 pr_err("%s: Wrong slab cache. %s but object is from %s\n",
353 __func__, s->name, cachep->name);
354 WARN_ON_ONCE(1);
355 return s;
356}
357
358static inline size_t slab_ksize(const struct kmem_cache *s)
359{
360#ifndef CONFIG_SLUB
361 return s->object_size;
362
363#else /* CONFIG_SLUB */
364# ifdef CONFIG_SLUB_DEBUG
365 /*
366 * Debugging requires use of the padding between object
367 * and whatever may come after it.
368 */
369 if (s->flags & (SLAB_RED_ZONE | SLAB_POISON))
370 return s->object_size;
371# endif
372 if (s->flags & SLAB_KASAN)
373 return s->object_size;
374 /*
375 * If we have the need to store the freelist pointer
376 * back there or track user information then we can
377 * only use the space before that information.
378 */
379 if (s->flags & (SLAB_DESTROY_BY_RCU | SLAB_STORE_USER))
380 return s->inuse;
381 /*
382 * Else we can use all the padding etc for the allocation
383 */
384 return s->size;
385#endif
386}
387
388static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s,
389 gfp_t flags)
390{
391 flags &= gfp_allowed_mask;
392 lockdep_trace_alloc(flags);
393 might_sleep_if(gfpflags_allow_blocking(flags));
394
395 if (should_failslab(s, flags))
396 return NULL;
397
398 if (memcg_kmem_enabled() &&
399 ((flags & __GFP_ACCOUNT) || (s->flags & SLAB_ACCOUNT)))
400 return memcg_kmem_get_cache(s);
401
402 return s;
403}
404
405static inline void slab_post_alloc_hook(struct kmem_cache *s, gfp_t flags,
406 size_t size, void **p)
407{
408 size_t i;
409
410 flags &= gfp_allowed_mask;
411 for (i = 0; i < size; i++) {
412 void *object = p[i];
413
414 kmemcheck_slab_alloc(s, flags, object, slab_ksize(s));
415 kmemleak_alloc_recursive(object, s->object_size, 1,
416 s->flags, flags);
417 kasan_slab_alloc(s, object, flags);
418 }
419
420 if (memcg_kmem_enabled())
421 memcg_kmem_put_cache(s);
422}
423
424#ifndef CONFIG_SLOB
425/*
426 * The slab lists for all objects.
427 */
428struct kmem_cache_node {
429 spinlock_t list_lock;
430
431#ifdef CONFIG_SLAB
432 struct list_head slabs_partial; /* partial list first, better asm code */
433 struct list_head slabs_full;
434 struct list_head slabs_free;
435 unsigned long num_slabs;
436 unsigned long free_objects;
437 unsigned int free_limit;
438 unsigned int colour_next; /* Per-node cache coloring */
439 struct array_cache *shared; /* shared per node */
440 struct alien_cache **alien; /* on other nodes */
441 unsigned long next_reap; /* updated without locking */
442 int free_touched; /* updated without locking */
443#endif
444
445#ifdef CONFIG_SLUB
446 unsigned long nr_partial;
447 struct list_head partial;
448#ifdef CONFIG_SLUB_DEBUG
449 atomic_long_t nr_slabs;
450 atomic_long_t total_objects;
451 struct list_head full;
452#endif
453#endif
454
455};
456
457static inline struct kmem_cache_node *get_node(struct kmem_cache *s, int node)
458{
459 return s->node[node];
460}
461
462/*
463 * Iterator over all nodes. The body will be executed for each node that has
464 * a kmem_cache_node structure allocated (which is true for all online nodes)
465 */
466#define for_each_kmem_cache_node(__s, __node, __n) \
467 for (__node = 0; __node < nr_node_ids; __node++) \
468 if ((__n = get_node(__s, __node)))
469
470#endif
471
472void *slab_start(struct seq_file *m, loff_t *pos);
473void *slab_next(struct seq_file *m, void *p, loff_t *pos);
474void slab_stop(struct seq_file *m, void *p);
475int memcg_slab_show(struct seq_file *m, void *p);
476
477void ___cache_free(struct kmem_cache *cache, void *x, unsigned long addr);
478
479#ifdef CONFIG_SLAB_FREELIST_RANDOM
480int cache_random_seq_create(struct kmem_cache *cachep, unsigned int count,
481 gfp_t gfp);
482void cache_random_seq_destroy(struct kmem_cache *cachep);
483#else
484static inline int cache_random_seq_create(struct kmem_cache *cachep,
485 unsigned int count, gfp_t gfp)
486{
487 return 0;
488}
489static inline void cache_random_seq_destroy(struct kmem_cache *cachep) { }
490#endif /* CONFIG_SLAB_FREELIST_RANDOM */
491
492#endif /* MM_SLAB_H */
493
generated by cgit at 2024-05-18 17:33:18 (GMT)