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1#ifndef _LINUX_SLAB_DEF_H
2#define _LINUX_SLAB_DEF_H
3
4/*
5 * Definitions unique to the original Linux SLAB allocator.
6 *
7 * What we provide here is a way to optimize the frequent kmalloc
8 * calls in the kernel by selecting the appropriate general cache
9 * if kmalloc was called with a size that can be established at
10 * compile time.
11 */
12
13#include <linux/init.h>
14#include <asm/page.h> /* kmalloc_sizes.h needs PAGE_SIZE */
15#include <asm/cache.h> /* kmalloc_sizes.h needs L1_CACHE_BYTES */
16#include <linux/compiler.h>
17
18/*
19 * struct kmem_cache
20 *
21 * manages a cache.
22 */
23
24struct kmem_cache {
25/* 1) Cache tunables. Protected by cache_chain_mutex */
26 unsigned int batchcount;
27 unsigned int limit;
28 unsigned int shared;
29
30 unsigned int size;
31 u32 reciprocal_buffer_size;
32/* 2) touched by every alloc & free from the backend */
33
34 unsigned int flags; /* constant flags */
35 unsigned int num; /* # of objs per slab */
36
37/* 3) cache_grow/shrink */
38 /* order of pgs per slab (2^n) */
39 unsigned int gfporder;
40
41 /* force GFP flags, e.g. GFP_DMA */
42 gfp_t allocflags;
43
44 size_t colour; /* cache colouring range */
45 unsigned int colour_off; /* colour offset */
46 struct kmem_cache *slabp_cache;
47 unsigned int slab_size;
48
49 /* constructor func */
50 void (*ctor)(void *obj);
51
52/* 4) cache creation/removal */
53 const char *name;
54 struct list_head list;
55 int refcount;
56 int object_size;
57 int align;
58
59/* 5) statistics */
60#ifdef CONFIG_DEBUG_SLAB
61 unsigned long num_active;
62 unsigned long num_allocations;
63 unsigned long high_mark;
64 unsigned long grown;
65 unsigned long reaped;
66 unsigned long errors;
67 unsigned long max_freeable;
68 unsigned long node_allocs;
69 unsigned long node_frees;
70 unsigned long node_overflow;
71 atomic_t allochit;
72 atomic_t allocmiss;
73 atomic_t freehit;
74 atomic_t freemiss;
75
76 /*
77 * If debugging is enabled, then the allocator can add additional
78 * fields and/or padding to every object. size contains the total
79 * object size including these internal fields, the following two
80 * variables contain the offset to the user object and its size.
81 */
82 int obj_offset;
83#endif /* CONFIG_DEBUG_SLAB */
84#ifdef CONFIG_MEMCG_KMEM
85 struct memcg_cache_params *memcg_params;
86#endif
87
88/* 6) per-cpu/per-node data, touched during every alloc/free */
89 /*
90 * We put array[] at the end of kmem_cache, because we want to size
91 * this array to nr_cpu_ids slots instead of NR_CPUS
92 * (see kmem_cache_init())
93 * We still use [NR_CPUS] and not [1] or [0] because cache_cache
94 * is statically defined, so we reserve the max number of cpus.
95 *
96 * We also need to guarantee that the list is able to accomodate a
97 * pointer for each node since "nodelists" uses the remainder of
98 * available pointers.
99 */
100 struct kmem_list3 **nodelists;
101 struct array_cache *array[NR_CPUS + MAX_NUMNODES];
102 /*
103 * Do not add fields after array[]
104 */
105};
106
107/* Size description struct for general caches. */
108struct cache_sizes {
109 size_t cs_size;
110 struct kmem_cache *cs_cachep;
111#ifdef CONFIG_ZONE_DMA
112 struct kmem_cache *cs_dmacachep;
113#endif
114};
115extern struct cache_sizes malloc_sizes[];
116
117void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
118void *__kmalloc(size_t size, gfp_t flags);
119
120#ifdef CONFIG_TRACING
121extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t);
122#else
123static __always_inline void *
124kmem_cache_alloc_trace(struct kmem_cache *cachep, gfp_t flags, size_t size)
125{
126 return kmem_cache_alloc(cachep, flags);
127}
128#endif
129
130static __always_inline void *kmalloc(size_t size, gfp_t flags)
131{
132 struct kmem_cache *cachep;
133 void *ret;
134
135 if (__builtin_constant_p(size)) {
136 int i = 0;
137
138 if (!size)
139 return ZERO_SIZE_PTR;
140
141#define CACHE(x) \
142 if (size <= x) \
143 goto found; \
144 else \
145 i++;
146#include <linux/kmalloc_sizes.h>
147#undef CACHE
148 return NULL;
149found:
150#ifdef CONFIG_ZONE_DMA
151 if (flags & GFP_DMA)
152 cachep = malloc_sizes[i].cs_dmacachep;
153 else
154#endif
155 cachep = malloc_sizes[i].cs_cachep;
156
157 ret = kmem_cache_alloc_trace(cachep, flags, size);
158
159 return ret;
160 }
161 return __kmalloc(size, flags);
162}
163
164#ifdef CONFIG_NUMA
165extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
166extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
167
168#ifdef CONFIG_TRACING
169extern void *kmem_cache_alloc_node_trace(struct kmem_cache *cachep,
170 gfp_t flags,
171 int nodeid,
172 size_t size);
173#else
174static __always_inline void *
175kmem_cache_alloc_node_trace(struct kmem_cache *cachep,
176 gfp_t flags,
177 int nodeid,
178 size_t size)
179{
180 return kmem_cache_alloc_node(cachep, flags, nodeid);
181}
182#endif
183
184static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
185{
186 struct kmem_cache *cachep;
187
188 if (__builtin_constant_p(size)) {
189 int i = 0;
190
191 if (!size)
192 return ZERO_SIZE_PTR;
193
194#define CACHE(x) \
195 if (size <= x) \
196 goto found; \
197 else \
198 i++;
199#include <linux/kmalloc_sizes.h>
200#undef CACHE
201 return NULL;
202found:
203#ifdef CONFIG_ZONE_DMA
204 if (flags & GFP_DMA)
205 cachep = malloc_sizes[i].cs_dmacachep;
206 else
207#endif
208 cachep = malloc_sizes[i].cs_cachep;
209
210 return kmem_cache_alloc_node_trace(cachep, flags, node, size);
211 }
212 return __kmalloc_node(size, flags, node);
213}
214
215#endif /* CONFIG_NUMA */
216
217#endif /* _LINUX_SLAB_DEF_H */