Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_SLUB_DEF_H
3#define _LINUX_SLUB_DEF_H
4
5/*
6 * SLUB : A Slab allocator without object queues.
7 *
8 * (C) 2007 SGI, Christoph Lameter
9 */
10#include <linux/kobject.h>
11
12enum stat_item {
13 ALLOC_FASTPATH, /* Allocation from cpu slab */
14 ALLOC_SLOWPATH, /* Allocation by getting a new cpu slab */
15 FREE_FASTPATH, /* Free to cpu slab */
16 FREE_SLOWPATH, /* Freeing not to cpu slab */
17 FREE_FROZEN, /* Freeing to frozen slab */
18 FREE_ADD_PARTIAL, /* Freeing moves slab to partial list */
19 FREE_REMOVE_PARTIAL, /* Freeing removes last object */
20 ALLOC_FROM_PARTIAL, /* Cpu slab acquired from node partial list */
21 ALLOC_SLAB, /* Cpu slab acquired from page allocator */
22 ALLOC_REFILL, /* Refill cpu slab from slab freelist */
23 ALLOC_NODE_MISMATCH, /* Switching cpu slab */
24 FREE_SLAB, /* Slab freed to the page allocator */
25 CPUSLAB_FLUSH, /* Abandoning of the cpu slab */
26 DEACTIVATE_FULL, /* Cpu slab was full when deactivated */
27 DEACTIVATE_EMPTY, /* Cpu slab was empty when deactivated */
28 DEACTIVATE_TO_HEAD, /* Cpu slab was moved to the head of partials */
29 DEACTIVATE_TO_TAIL, /* Cpu slab was moved to the tail of partials */
30 DEACTIVATE_REMOTE_FREES,/* Slab contained remotely freed objects */
31 DEACTIVATE_BYPASS, /* Implicit deactivation */
32 ORDER_FALLBACK, /* Number of times fallback was necessary */
33 CMPXCHG_DOUBLE_CPU_FAIL,/* Failure of this_cpu_cmpxchg_double */
34 CMPXCHG_DOUBLE_FAIL, /* Number of times that cmpxchg double did not match */
35 CPU_PARTIAL_ALLOC, /* Used cpu partial on alloc */
36 CPU_PARTIAL_FREE, /* Refill cpu partial on free */
37 CPU_PARTIAL_NODE, /* Refill cpu partial from node partial */
38 CPU_PARTIAL_DRAIN, /* Drain cpu partial to node partial */
39 NR_SLUB_STAT_ITEMS };
40
41struct kmem_cache_cpu {
42 void **freelist; /* Pointer to next available object */
43 unsigned long tid; /* Globally unique transaction id */
44 struct page *page; /* The slab from which we are allocating */
45#ifdef CONFIG_SLUB_CPU_PARTIAL
46 struct page *partial; /* Partially allocated frozen slabs */
47#endif
48#ifdef CONFIG_SLUB_STATS
49 unsigned stat[NR_SLUB_STAT_ITEMS];
50#endif
51};
52
53#ifdef CONFIG_SLUB_CPU_PARTIAL
54#define slub_percpu_partial(c) ((c)->partial)
55
56#define slub_set_percpu_partial(c, p) \
57({ \
58 slub_percpu_partial(c) = (p)->next; \
59})
60
61#define slub_percpu_partial_read_once(c) READ_ONCE(slub_percpu_partial(c))
62#else
63#define slub_percpu_partial(c) NULL
64
65#define slub_set_percpu_partial(c, p)
66
67#define slub_percpu_partial_read_once(c) NULL
68#endif // CONFIG_SLUB_CPU_PARTIAL
69
70/*
71 * Word size structure that can be atomically updated or read and that
72 * contains both the order and the number of objects that a slab of the
73 * given order would contain.
74 */
75struct kmem_cache_order_objects {
76 unsigned long x;
77};
78
79/*
80 * Slab cache management.
81 */
82struct kmem_cache {
83 struct kmem_cache_cpu __percpu *cpu_slab;
84 /* Used for retriving partial slabs etc */
85 slab_flags_t flags;
86 unsigned long min_partial;
87 int size; /* The size of an object including meta data */
88 int object_size; /* The size of an object without meta data */
89 int offset; /* Free pointer offset. */
90#ifdef CONFIG_SLUB_CPU_PARTIAL
91 int cpu_partial; /* Number of per cpu partial objects to keep around */
92#endif
93 struct kmem_cache_order_objects oo;
94
95 /* Allocation and freeing of slabs */
96 struct kmem_cache_order_objects max;
97 struct kmem_cache_order_objects min;
98 gfp_t allocflags; /* gfp flags to use on each alloc */
99 int refcount; /* Refcount for slab cache destroy */
100 void (*ctor)(void *);
101 int inuse; /* Offset to metadata */
102 int align; /* Alignment */
103 int reserved; /* Reserved bytes at the end of slabs */
104 int red_left_pad; /* Left redzone padding size */
105 const char *name; /* Name (only for display!) */
106 struct list_head list; /* List of slab caches */
107#ifdef CONFIG_SYSFS
108 struct kobject kobj; /* For sysfs */
109 struct work_struct kobj_remove_work;
110#endif
111#ifdef CONFIG_MEMCG
112 struct memcg_cache_params memcg_params;
113 int max_attr_size; /* for propagation, maximum size of a stored attr */
114#ifdef CONFIG_SYSFS
115 struct kset *memcg_kset;
116#endif
117#endif
118
119#ifdef CONFIG_SLAB_FREELIST_HARDENED
120 unsigned long random;
121#endif
122
123#ifdef CONFIG_NUMA
124 /*
125 * Defragmentation by allocating from a remote node.
126 */
127 int remote_node_defrag_ratio;
128#endif
129
130#ifdef CONFIG_SLAB_FREELIST_RANDOM
131 unsigned int *random_seq;
132#endif
133
134#ifdef CONFIG_KASAN
135 struct kasan_cache kasan_info;
136#endif
137
138 size_t useroffset; /* Usercopy region offset */
139 size_t usersize; /* Usercopy region size */
140
141 struct kmem_cache_node *node[MAX_NUMNODES];
142};
143
144#ifdef CONFIG_SLUB_CPU_PARTIAL
145#define slub_cpu_partial(s) ((s)->cpu_partial)
146#define slub_set_cpu_partial(s, n) \
147({ \
148 slub_cpu_partial(s) = (n); \
149})
150#else
151#define slub_cpu_partial(s) (0)
152#define slub_set_cpu_partial(s, n)
153#endif // CONFIG_SLUB_CPU_PARTIAL
154
155#ifdef CONFIG_SYSFS
156#define SLAB_SUPPORTS_SYSFS
157void sysfs_slab_release(struct kmem_cache *);
158#else
159static inline void sysfs_slab_release(struct kmem_cache *s)
160{
161}
162#endif
163
164void object_err(struct kmem_cache *s, struct page *page,
165 u8 *object, char *reason);
166
167void *fixup_red_left(struct kmem_cache *s, void *p);
168
169static inline void *nearest_obj(struct kmem_cache *cache, struct page *page,
170 void *x) {
171 void *object = x - (x - page_address(page)) % cache->size;
172 void *last_object = page_address(page) +
173 (page->objects - 1) * cache->size;
174 void *result = (unlikely(object > last_object)) ? last_object : object;
175
176 result = fixup_red_left(cache, result);
177 return result;
178}
179
180#endif /* _LINUX_SLUB_DEF_H */