arch/x86/include/asm/jump_label.h

   1 #ifndef _ASM_X86_JUMP_LABEL_H
   2 #define _ASM_X86_JUMP_LABEL_H
   3
   4 #ifdef __KERNEL__
   5
   6 #include <linux/types.h>
   7 #include <asm/nops.h>
   8
   9 #define JUMP_LABEL_NOP_SIZE 5
  10
  11 # define JUMP_LABEL_INITIAL_NOP ".byte 0xe9 \n\t .long 0\n\t"
  12
  13 # define JUMP_LABEL(key, label)                                 \
  14         do {                                                    \
  15                 asm goto("1:"                                   \
  16                         JUMP_LABEL_INITIAL_NOP                  \
  17                         ".pushsection __jump_table,  \"aw\" \n\t"\
  18                         _ASM_PTR "1b, %l[" #label "], %c0 \n\t" \
  19                         ".popsection \n\t"                      \
  20                         : :  "i" (key) :  : label);             \
  21         } while (0)
  22
  23 #endif /* __KERNEL__ */
  24
  25 #ifdef CONFIG_X86_64
  26 typedef u64 jump_label_t;
  27 #else
  28 typedef u32 jump_label_t;
  29 #endif
  30
  31 struct jump_entry {
  32         jump_label_t code;
  33         jump_label_t target;
  34         jump_label_t key;
  35 };
  36
  37 #endif