Linux Kernel  3.7.1
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jump_label.h
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1 #ifndef _ASM_ARM_JUMP_LABEL_H
2 #define _ASM_ARM_JUMP_LABEL_H
3 
4 #ifdef __KERNEL__
5 
6 #include <linux/types.h>
7 #include <asm/system.h>
8 
9 #define JUMP_LABEL_NOP_SIZE 4
10 
11 #ifdef CONFIG_THUMB2_KERNEL
12 #define JUMP_LABEL_NOP "nop.w"
13 #else
14 #define JUMP_LABEL_NOP "nop"
15 #endif
16 
17 static __always_inline bool arch_static_branch(struct static_key *key)
18 {
19  asm goto("1:\n\t"
20  JUMP_LABEL_NOP "\n\t"
21  ".pushsection __jump_table, \"aw\"\n\t"
22  ".word 1b, %l[l_yes], %c0\n\t"
23  ".popsection\n\t"
24  : : "i" (key) : : l_yes);
25 
26  return false;
27 l_yes:
28  return true;
29 }
30 
31 #endif /* __KERNEL__ */
32 
33 typedef u32 jump_label_t;
34 
35 struct jump_entry {
36  jump_label_t code;
37  jump_label_t target;
38  jump_label_t key;
39 };
40 
41 #endif