summaryrefslogtreecommitdiffstats
path: root/include/linux/slub_def.h
blob: 3a1a1dbc6f49479f61f4c1a6588e6a672f0b0663 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_SLUB_DEF_H
#define _LINUX_SLUB_DEF_H

/*
 * SLUB : A Slab allocator without object queues.
 *
 * (C) 2007 SGI, Christoph Lameter
 */
#include <linux/kobject.h>

enum stat_item {
	ALLOC_FASTPATH,		/* Allocation from cpu slab */
	ALLOC_SLOWPATH,		/* Allocation by getting a new cpu slab */
	FREE_FASTPATH,		/* Free to cpu slab */
	FREE_SLOWPATH,		/* Freeing not to cpu slab */
	FREE_FROZEN,		/* Freeing to frozen slab */
	FREE_ADD_PARTIAL,	/* Freeing moves slab to partial list */
	FREE_REMOVE_PARTIAL,	/* Freeing removes last object */
	ALLOC_FROM_PARTIAL,	/* Cpu slab acquired from node partial list */
	ALLOC_SLAB,		/* Cpu slab acquired from page allocator */
	ALLOC_REFILL,		/* Refill cpu slab from slab freelist */
	ALLOC_NODE_MISMATCH,	/* Switching cpu slab */
	FREE_SLAB,		/* Slab freed to the page allocator */
	CPUSLAB_FLUSH,		/* Abandoning of the cpu slab */
	DEACTIVATE_FULL,	/* Cpu slab was full when deactivated */
	DEACTIVATE_EMPTY,	/* Cpu slab was empty when deactivated */
	DEACTIVATE_TO_HEAD,	/* Cpu slab was moved to the head of partials */
	DEACTIVATE_TO_TAIL,	/* Cpu slab was moved to the tail of partials */
	DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */
	DEACTIVATE_BYPASS,	/* Implicit deactivation */
	ORDER_FALLBACK,		/* Number of times fallback was necessary */
	CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */
	CMPXCHG_DOUBLE_FAIL,	/* Number of times that cmpxchg double did not match */
	CPU_PARTIAL_ALLOC,	/* Used cpu partial on alloc */
	CPU_PARTIAL_FREE,	/* Refill cpu partial on free */
	CPU_PARTIAL_NODE,	/* Refill cpu partial from node partial */
	CPU_PARTIAL_DRAIN,	/* Drain cpu partial to node partial */
	NR_SLUB_STAT_ITEMS };

struct kmem_cache_cpu {
	void **freelist;	/* Pointer to next available object */
	unsigned long tid;	/* Globally unique transaction id */
	struct page *page;	/* The slab from which we are allocating */
#ifdef CONFIG_SLUB_CPU_PARTIAL
	struct page *partial;	/* Partially allocated frozen slabs */
#endif
#ifdef CONFIG_SLUB_STATS
	unsigned stat[NR_SLUB_STAT_ITEMS];
#endif
};

#ifdef CONFIG_SLUB_CPU_PARTIAL
#define slub_percpu_partial(c)		((c)->partial)

#define slub_set_percpu_partial(c, p)		\
({						\
	slub_percpu_partial(c) = (p)->next;	\
})

#define slub_percpu_partial_read_once(c)     READ_ONCE(slub_percpu_partial(c))
#else
#define slub_percpu_partial(c)			NULL

#define slub_set_percpu_partial(c, p)

#define slub_percpu_partial_read_once(c)	NULL
#endif // CONFIG_SLUB_CPU_PARTIAL

/*
 * Word size structure that can be atomically updated or read and that
 * contains both the order and the number of objects that a slab of the
 * given order would contain.
 */
struct kmem_cache_order_objects {
	unsigned int x;
};

/*
 * Slab cache management.
 */
struct kmem_cache {
	struct kmem_cache_cpu __percpu *cpu_slab;
	/* Used for retriving partial slabs etc */
	slab_flags_t flags;
	unsigned long min_partial;
	unsigned int size;	/* The size of an object including meta data */
	unsigned int object_size;/* The size of an object without meta data */
	unsigned int offset;	/* Free pointer offset. */
#ifdef CONFIG_SLUB_CPU_PARTIAL
	/* Number of per cpu partial objects to keep around */
	unsigned int cpu_partial;
#endif
	struct kmem_cache_order_objects oo;

	/* Allocation and freeing of slabs */
	struct kmem_cache_order_objects max;
	struct kmem_cache_order_objects min;
	gfp_t allocflags;	/* gfp flags to use on each alloc */
	int refcount;		/* Refcount for slab cache destroy */
	void (*ctor)(void *);
	unsigned int inuse;		/* Offset to metadata */
	unsigned int align;		/* Alignment */
	unsigned int red_left_pad;	/* Left redzone padding size */
	const char *name;	/* Name (only for display!) */
	struct list_head list;	/* List of slab caches */
#ifdef CONFIG_SYSFS
	struct kobject kobj;	/* For sysfs */
	struct work_struct kobj_remove_work;
#endif
#ifdef CONFIG_MEMCG
	struct memcg_cache_params memcg_params;
	/* for propagation, maximum size of a stored attr */
	unsigned int max_attr_size;
#ifdef CONFIG_SYSFS
	struct kset *memcg_kset;
#endif
#endif

#ifdef CONFIG_SLAB_FREELIST_HARDENED
	unsigned long random;
#endif

#ifdef CONFIG_NUMA
	/*
	 * Defragmentation by allocating from a remote node.
	 */
	unsigned int remote_node_defrag_ratio;
#endif

#ifdef CONFIG_SLAB_FREELIST_RANDOM
	unsigned int *random_seq;
#endif

#ifdef CONFIG_KASAN
	struct kasan_cache kasan_info;
#endif

	unsigned int useroffset;	/* Usercopy region offset */
	unsigned int usersize;		/* Usercopy region size */

	struct kmem_cache_node *node[MAX_NUMNODES];
};

#ifdef CONFIG_SLUB_CPU_PARTIAL
#define slub_cpu_partial(s)		((s)->cpu_partial)
#define slub_set_cpu_partial(s, n)		\
({						\
	slub_cpu_partial(s) = (n);		\
})
#else
#define slub_cpu_partial(s)		(0)
#define slub_set_cpu_partial(s, n)
#endif // CONFIG_SLUB_CPU_PARTIAL

#ifdef CONFIG_SYSFS
#define SLAB_SUPPORTS_SYSFS
void sysfs_slab_unlink(struct kmem_cache *);
void sysfs_slab_release(struct kmem_cache *);
#else
static inline void sysfs_slab_unlink(struct kmem_cache *s)
{
}
static inline void sysfs_slab_release(struct kmem_cache *s)
{
}
#endif

void object_err(struct kmem_cache *s, struct page *page,
		u8 *object, char *reason);

void *fixup_red_left(struct kmem_cache *s, void *p);

static inline void *nearest_obj(struct kmem_cache *cache, struct page *page,
				void *x) {
	void *object = x - (x - page_address(page)) % cache->size;
	void *last_object = page_address(page) +
		(page->objects - 1) * cache->size;
	void *result = (unlikely(object > last_object)) ? last_object : object;

	result = fixup_red_left(cache, result);
	return result;
}

#endif /* _LINUX_SLUB_DEF_H */