1 #ifndef __LINUX_PERCPU_H
2 #define __LINUX_PERCPU_H
4 #include <linux/preempt.h>
5 #include <linux/slab.h> /* For kmalloc() */
7 #include <linux/cpumask.h>
9 #include <asm/percpu.h>
12 #define DEFINE_PER_CPU(type, name) \
13 __attribute__((__section__(".data.percpu"))) \
14 PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
17 #define SHARED_ALIGNED_SECTION ".data.percpu"
19 #define SHARED_ALIGNED_SECTION ".data.percpu.shared_aligned"
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
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
31 #define DEFINE_PER_CPU(type, name) \
32 PER_CPU_ATTRIBUTES __typeof__(type) per_cpu__##name
34 #define DEFINE_PER_CPU_SHARED_ALIGNED(type, name) \
35 DEFINE_PER_CPU(type, name)
37 #define DEFINE_PER_CPU_PAGE_ALIGNED(type, name) \
38 DEFINE_PER_CPU(type, name)
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)
44 /* Enough to cover all DEFINE_PER_CPUs in kernel, including modules. */
45 #ifndef PERCPU_ENOUGH_ROOM
47 #define PERCPU_MODULE_RESERVE 8192
49 #define PERCPU_MODULE_RESERVE 0
52 #define PERCPU_ENOUGH_ROOM \
53 (__per_cpu_end - __per_cpu_start + PERCPU_MODULE_RESERVE)
54 #endif /* PERCPU_ENOUGH_ROOM */
57 * Must be an lvalue. Since @var must be a simple identifier,
58 * we force a syntax error here if it isn't.
60 #define get_cpu_var(var) (*({ \
61 extern int simple_identifier_##var(void); \
63 &__get_cpu_var(var); }))
64 #define put_cpu_var(var) preempt_enable()
72 #define __percpu_disguise(pdata) (struct percpu_data *)~(unsigned long)(pdata)
74 * Use this to get to a cpu's version of the per-cpu object dynamically
75 * allocated. Non-atomic access to the current CPU's version should
76 * probably be combined with get_cpu()/put_cpu().
78 #define percpu_ptr(ptr, cpu) \
80 struct percpu_data *__p = __percpu_disguise(ptr); \
81 (__typeof__(ptr))__p->ptrs[(cpu)]; \
84 extern void *percpu_populate(void *__pdata
, size_t size
, gfp_t gfp
, int cpu
);
85 extern void percpu_depopulate(void *__pdata
, int cpu
);
86 extern int __percpu_populate_mask(void *__pdata
, size_t size
, gfp_t gfp
,
88 extern void __percpu_depopulate_mask(void *__pdata
, cpumask_t
*mask
);
89 extern void *__percpu_alloc_mask(size_t size
, gfp_t gfp
, cpumask_t
*mask
);
90 extern void percpu_free(void *__pdata
);
92 #else /* CONFIG_SMP */
94 #define percpu_ptr(ptr, cpu) ({ (void)(cpu); (ptr); })
96 static inline void percpu_depopulate(void *__pdata
, int cpu
)
100 static inline void __percpu_depopulate_mask(void *__pdata
, cpumask_t
*mask
)
104 static inline void *percpu_populate(void *__pdata
, size_t size
, gfp_t gfp
,
107 return percpu_ptr(__pdata
, cpu
);
110 static inline int __percpu_populate_mask(void *__pdata
, size_t size
, gfp_t gfp
,
116 static __always_inline
void *__percpu_alloc_mask(size_t size
, gfp_t gfp
, cpumask_t
*mask
)
118 return kzalloc(size
, gfp
);
121 static inline void percpu_free(void *__pdata
)
126 #endif /* CONFIG_SMP */
128 #define percpu_populate_mask(__pdata, size, gfp, mask) \
129 __percpu_populate_mask((__pdata), (size), (gfp), &(mask))
130 #define percpu_depopulate_mask(__pdata, mask) \
131 __percpu_depopulate_mask((__pdata), &(mask))
132 #define percpu_alloc_mask(size, gfp, mask) \
133 __percpu_alloc_mask((size), (gfp), &(mask))
135 #define percpu_alloc(size, gfp) percpu_alloc_mask((size), (gfp), cpu_online_map)
137 /* (legacy) interface for use without CPU hotplug handling */
139 #define __alloc_percpu(size) percpu_alloc_mask((size), GFP_KERNEL, \
141 #define alloc_percpu(type) (type *)__alloc_percpu(sizeof(type))
142 #define free_percpu(ptr) percpu_free((ptr))
143 #define per_cpu_ptr(ptr, cpu) percpu_ptr((ptr), (cpu))
145 #endif /* __LINUX_PERCPU_H */