diff options
Diffstat (limited to 'include/linux/percpu.h')
-rw-r--r-- | include/linux/percpu.h | 191 |
1 files changed, 127 insertions, 64 deletions
diff --git a/include/linux/percpu.h b/include/linux/percpu.h index 9f2a3751873a..1581ff235c7e 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h | |||
@@ -5,53 +5,22 @@ | |||
5 | #include <linux/slab.h> /* For kmalloc() */ | 5 | #include <linux/slab.h> /* For kmalloc() */ |
6 | #include <linux/smp.h> | 6 | #include <linux/smp.h> |
7 | #include <linux/cpumask.h> | 7 | #include <linux/cpumask.h> |
8 | #include <linux/pfn.h> | ||
8 | 9 | ||
9 | #include <asm/percpu.h> | 10 | #include <asm/percpu.h> |
10 | 11 | ||
11 | #ifdef CONFIG_SMP | 12 | /* enough to cover all DEFINE_PER_CPUs in modules */ |
12 | #define DEFINE_PER_CPU(type, name) \ | ||
13 | __attribute__((__section__(".data.percpu"))) \ | ||
14 | PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name | ||
15 | |||
16 | #ifdef MODULE | ||
17 | #define SHARED_ALIGNED_SECTION ".data.percpu" | ||
18 | #else | ||
19 | #define SHARED_ALIGNED_SECTION ".data.percpu.shared_aligned" | ||
20 | #endif | ||
21 | |||
22 | #define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \ | ||
23 | __attribute__((__section__(SHARED_ALIGNED_SECTION))) \ | ||
24 | PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name \ | ||
25 | ____cacheline_aligned_in_smp | ||
26 | |||
27 | #define DEFINE_PER_CPU_PAGE_ALIGNED(type, name) \ | ||
28 | __attribute__((__section__(".data.percpu.page_aligned"))) \ | ||
29 | PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name | ||
30 | #else | ||
31 | #define DEFINE_PER_CPU(type, name) \ | ||
32 | PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name | ||
33 | |||
34 | #define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \ | ||
35 | DEFINE_PER_CPU(type, name) | ||
36 | |||
37 | #define DEFINE_PER_CPU_PAGE_ALIGNED(type, name) \ | ||
38 | DEFINE_PER_CPU(type, name) | ||
39 | #endif | ||
40 | |||
41 | #define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var) | ||
42 | #define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var) | ||
43 | |||
44 | /* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */ | ||
45 | #ifndef PERCPU_ENOUGH_ROOM | ||
46 | #ifdef CONFIG_MODULES | 13 | #ifdef CONFIG_MODULES |
47 | #define PERCPU_MODULE_RESERVE 8192 | 14 | #define PERCPU_MODULE_RESERVE (8 << 10) |
48 | #else | 15 | #else |
49 | #define PERCPU_MODULE_RESERVE 0 | 16 | #define PERCPU_MODULE_RESERVE 0 |
50 | #endif | 17 | #endif |
51 | 18 | ||
19 | #ifndef PERCPU_ENOUGH_ROOM | ||
52 | #define PERCPU_ENOUGH_ROOM \ | 20 | #define PERCPU_ENOUGH_ROOM \ |
53 | (__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE) | 21 | (ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES) + \ |
54 | #endif /* PERCPU_ENOUGH_ROOM */ | 22 | PERCPU_MODULE_RESERVE) |
23 | #endif | ||
55 | 24 | ||
56 | /* | 25 | /* |
57 | * Must be an lvalue. Since @var must be a simple identifier, | 26 | * Must be an lvalue. Since @var must be a simple identifier, |
@@ -65,52 +34,146 @@ | |||
65 | 34 | ||
66 | #ifdef CONFIG_SMP | 35 | #ifdef CONFIG_SMP |
67 | 36 | ||
37 | #ifdef CONFIG_HAVE_DYNAMIC_PER_CPU_AREA | ||
38 | |||
39 | /* minimum unit size, also is the maximum supported allocation size */ | ||
40 | #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(64 << 10) | ||
41 | |||
42 | /* | ||
43 | * PERCPU_DYNAMIC_RESERVE indicates the amount of free area to piggy | ||
44 | * back on the first chunk for dynamic percpu allocation if arch is | ||
45 | * manually allocating and mapping it for faster access (as a part of | ||
46 | * large page mapping for example). | ||
47 | * | ||
48 | * The following values give between one and two pages of free space | ||
49 | * after typical minimal boot (2-way SMP, single disk and NIC) with | ||
50 | * both defconfig and a distro config on x86_64 and 32. More | ||
51 | * intelligent way to determine this would be nice. | ||
52 | */ | ||
53 | #if BITS_PER_LONG > 32 | ||
54 | #define PERCPU_DYNAMIC_RESERVE (20 << 10) | ||
55 | #else | ||
56 | #define PERCPU_DYNAMIC_RESERVE (12 << 10) | ||
57 | #endif | ||
58 | |||
59 | extern void *pcpu_base_addr; | ||
60 | |||
61 | typedef struct page * (*pcpu_get_page_fn_t)(unsigned int cpu, int pageno); | ||
62 | typedef void (*pcpu_populate_pte_fn_t)(unsigned long addr); | ||
63 | |||
64 | extern size_t __init pcpu_setup_first_chunk(pcpu_get_page_fn_t get_page_fn, | ||
65 | size_t static_size, size_t reserved_size, | ||
66 | ssize_t dyn_size, ssize_t unit_size, | ||
67 | void *base_addr, | ||
68 | pcpu_populate_pte_fn_t populate_pte_fn); | ||
69 | |||
70 | extern ssize_t __init pcpu_embed_first_chunk( | ||
71 | size_t static_size, size_t reserved_size, | ||
72 | ssize_t dyn_size, ssize_t unit_size); | ||
73 | |||
74 | /* | ||
75 | * Use this to get to a cpu's version of the per-cpu object | ||
76 | * dynamically allocated. Non-atomic access to the current CPU's | ||
77 | * version should probably be combined with get_cpu()/put_cpu(). | ||
78 | */ | ||
79 | #define per_cpu_ptr(ptr, cpu) SHIFT_PERCPU_PTR((ptr), per_cpu_offset((cpu))) | ||
80 | |||
81 | extern void *__alloc_reserved_percpu(size_t size, size_t align); | ||
82 | |||
83 | #else /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */ | ||
84 | |||
68 | struct percpu_data { | 85 | struct percpu_data { |
69 | void *ptrs[1]; | 86 | void *ptrs[1]; |
70 | }; | 87 | }; |
71 | 88 | ||
72 | #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata) | 89 | #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata) |
73 | /* | 90 | |
74 | * Use this to get to a cpu's version of the per-cpu object dynamically | 91 | #define per_cpu_ptr(ptr, cpu) \ |
75 | * allocated. Non-atomic access to the current CPU's version should | 92 | ({ \ |
76 | * probably be combined with get_cpu()/put_cpu(). | 93 | struct percpu_data *__p = __percpu_disguise(ptr); \ |
77 | */ | 94 | (__typeof__(ptr))__p->ptrs[(cpu)]; \ |
78 | #define percpu_ptr(ptr, cpu) \ | ||
79 | ({ \ | ||
80 | struct percpu_data *__p = __percpu_disguise(ptr); \ | ||
81 | (__typeof__(ptr))__p->ptrs[(cpu)]; \ | ||
82 | }) | 95 | }) |
83 | 96 | ||
84 | extern void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask); | 97 | #endif /* CONFIG_HAVE_DYNAMIC_PER_CPU_AREA */ |
85 | extern void percpu_free(void *__pdata); | 98 | |
99 | extern void *__alloc_percpu(size_t size, size_t align); | ||
100 | extern void free_percpu(void *__pdata); | ||
86 | 101 | ||
87 | #else /* CONFIG_SMP */ | 102 | #else /* CONFIG_SMP */ |
88 | 103 | ||
89 | #define percpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); }) | 104 | #define per_cpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); }) |
90 | 105 | ||
91 | static __always_inline void *__percpu_alloc_mask(size_t size, gfp_t gfp, cpumask_t *mask) | 106 | static inline void *__alloc_percpu(size_t size, size_t align) |
92 | { | 107 | { |
93 | return kzalloc(size, gfp); | 108 | /* |
109 | * Can't easily make larger alignment work with kmalloc. WARN | ||
110 | * on it. Larger alignment should only be used for module | ||
111 | * percpu sections on SMP for which this path isn't used. | ||
112 | */ | ||
113 | WARN_ON_ONCE(align > SMP_CACHE_BYTES); | ||
114 | return kzalloc(size, GFP_KERNEL); | ||
94 | } | 115 | } |
95 | 116 | ||
96 | static inline void percpu_free(void *__pdata) | 117 | static inline void free_percpu(void *p) |
97 | { | 118 | { |
98 | kfree(__pdata); | 119 | kfree(p); |
99 | } | 120 | } |
100 | 121 | ||
101 | #endif /* CONFIG_SMP */ | 122 | #endif /* CONFIG_SMP */ |
102 | 123 | ||
103 | #define percpu_alloc_mask(size, gfp, mask) \ | 124 | #define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type), \ |
104 | __percpu_alloc_mask((size), (gfp), &(mask)) | 125 | __alignof__(type)) |
105 | 126 | ||
106 | #define percpu_alloc(size, gfp) percpu_alloc_mask((size), (gfp), cpu_online_map) | 127 | /* |
128 | * Optional methods for optimized non-lvalue per-cpu variable access. | ||
129 | * | ||
130 | * @var can be a percpu variable or a field of it and its size should | ||
131 | * equal char, int or long. percpu_read() evaluates to a lvalue and | ||
132 | * all others to void. | ||
133 | * | ||
134 | * These operations are guaranteed to be atomic w.r.t. preemption. | ||
135 | * The generic versions use plain get/put_cpu_var(). Archs are | ||
136 | * encouraged to implement single-instruction alternatives which don't | ||
137 | * require preemption protection. | ||
138 | */ | ||
139 | #ifndef percpu_read | ||
140 | # define percpu_read(var) \ | ||
141 | ({ \ | ||
142 | typeof(per_cpu_var(var)) __tmp_var__; \ | ||
143 | __tmp_var__ = get_cpu_var(var); \ | ||
144 | put_cpu_var(var); \ | ||
145 | __tmp_var__; \ | ||
146 | }) | ||
147 | #endif | ||
107 | 148 | ||
108 | /* (legacy) interface for use without CPU hotplug handling */ | 149 | #define __percpu_generic_to_op(var, val, op) \ |
150 | do { \ | ||
151 | get_cpu_var(var) op val; \ | ||
152 | put_cpu_var(var); \ | ||
153 | } while (0) | ||
109 | 154 | ||
110 | #define __alloc_percpu(size) percpu_alloc_mask((size), GFP_KERNEL, \ | 155 | #ifndef percpu_write |
111 | cpu_possible_map) | 156 | # define percpu_write(var, val) __percpu_generic_to_op(var, (val), =) |
112 | #define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type)) | 157 | #endif |
113 | #define free_percpu(ptr) percpu_free((ptr)) | 158 | |
114 | #define per_cpu_ptr(ptr, cpu) percpu_ptr((ptr), (cpu)) | 159 | #ifndef percpu_add |
160 | # define percpu_add(var, val) __percpu_generic_to_op(var, (val), +=) | ||
161 | #endif | ||
162 | |||
163 | #ifndef percpu_sub | ||
164 | # define percpu_sub(var, val) __percpu_generic_to_op(var, (val), -=) | ||
165 | #endif | ||
166 | |||
167 | #ifndef percpu_and | ||
168 | # define percpu_and(var, val) __percpu_generic_to_op(var, (val), &=) | ||
169 | #endif | ||
170 | |||
171 | #ifndef percpu_or | ||
172 | # define percpu_or(var, val) __percpu_generic_to_op(var, (val), |=) | ||
173 | #endif | ||
174 | |||
175 | #ifndef percpu_xor | ||
176 | # define percpu_xor(var, val) __percpu_generic_to_op(var, (val), ^=) | ||
177 | #endif | ||
115 | 178 | ||
116 | #endif /* __LINUX_PERCPU_H */ | 179 | #endif /* __LINUX_PERCPU_H */ |