1 #ifndef __ARCH_I386_PERCPU__
2 #define __ARCH_I386_PERCPU__
7 * PER_CPU finds an address of a per-cpu variable.
11 * reg - 32bit register
13 * The resulting address is stored in the "reg" argument.
16 * PER_CPU(cpu_gdt_descr, %ebx)
19 #define PER_CPU(var, reg) \
20 movl %fs:per_cpu__##this_cpu_off, reg; \
21 lea per_cpu__##var(reg), reg
22 #define PER_CPU_VAR(var) %fs:per_cpu__##var
24 #define PER_CPU(var, reg) \
25 movl $per_cpu__##var, reg
26 #define PER_CPU_VAR(var) per_cpu__##var
29 #else /* ...!ASSEMBLY */
32 * PER_CPU finds an address of a per-cpu variable.
36 * cpu - 32bit register containing the current CPU number
38 * The resulting address is stored in the "cpu" argument.
41 * PER_CPU(cpu_gdt_descr, %ebx)
44 /* Same as generic implementation except for optimized local access. */
45 #define __GENERIC_PER_CPU
47 /* This is used for other cpus to find our section. */
48 extern unsigned long __per_cpu_offset[];
50 /* Separate out the type, so (int[3], foo) works. */
51 #define DECLARE_PER_CPU(type, name) extern __typeof__(type) per_cpu__##name
52 #define DEFINE_PER_CPU(type, name) \
53 __attribute__((__section__(".data.percpu"))) __typeof__(type) per_cpu__##name
55 /* We can use this directly for local CPU (faster). */
56 DECLARE_PER_CPU(unsigned long, this_cpu_off);
58 /* var is in discarded region: offset to particular copy we want */
59 #define per_cpu(var, cpu) (*({ \
60 extern int simple_indentifier_##var(void); \
61 RELOC_HIDE(&per_cpu__##var, __per_cpu_offset[cpu]); }))
63 #define __raw_get_cpu_var(var) (*({ \
64 extern int simple_indentifier_##var(void); \
65 RELOC_HIDE(&per_cpu__##var, x86_read_percpu(this_cpu_off)); \
68 #define __get_cpu_var(var) __raw_get_cpu_var(var)
70 /* A macro to avoid #include hell... */
71 #define percpu_modcopy(pcpudst, src, size) \
74 for_each_possible_cpu(__i) \
75 memcpy((pcpudst)+__per_cpu_offset[__i], \
79 #define EXPORT_PER_CPU_SYMBOL(var) EXPORT_SYMBOL(per_cpu__##var)
80 #define EXPORT_PER_CPU_SYMBOL_GPL(var) EXPORT_SYMBOL_GPL(per_cpu__##var)
82 /* fs segment starts at (positive) offset == __per_cpu_offset[cpu] */
83 #define __percpu_seg "%%fs:"
85 #include <asm-generic/percpu.h>
86 #define __percpu_seg ""
89 /* For arch-specific code, we can use direct single-insn ops (they
90 * don't give an lvalue though). */
91 extern void __bad_percpu_size(void);
93 #define percpu_to_op(op,var,val) \
95 typedef typeof(var) T__; \
96 if (0) { T__ tmp__; tmp__ = (val); } \
97 switch (sizeof(var)) { \
99 asm(op "b %1,"__percpu_seg"%0" \
104 asm(op "w %1,"__percpu_seg"%0" \
109 asm(op "l %1,"__percpu_seg"%0" \
113 default: __bad_percpu_size(); \
117 #define percpu_from_op(op,var) \
120 switch (sizeof(var)) { \
122 asm(op "b "__percpu_seg"%1,%0" \
127 asm(op "w "__percpu_seg"%1,%0" \
132 asm(op "l "__percpu_seg"%1,%0" \
136 default: __bad_percpu_size(); \
140 #define x86_read_percpu(var) percpu_from_op("mov", per_cpu__##var)
141 #define x86_write_percpu(var,val) percpu_to_op("mov", per_cpu__##var, val)
142 #define x86_add_percpu(var,val) percpu_to_op("add", per_cpu__##var, val)
143 #define x86_sub_percpu(var,val) percpu_to_op("sub", per_cpu__##var, val)
144 #define x86_or_percpu(var,val) percpu_to_op("or", per_cpu__##var, val)
145 #endif /* !__ASSEMBLY__ */
147 #endif /* __ARCH_I386_PERCPU__ */