arch/powerpc/include/asm/jump_label.h

   1 #ifndef _ASM_POWERPC_JUMP_LABEL_H
   2 #define _ASM_POWERPC_JUMP_LABEL_H
   3
   4 /*
   5  * Copyright 2010 Michael Ellerman, IBM Corp.
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version
  10  * 2 of the License, or (at your option) any later version.
  11  */
  12
  13 #include <linux/types.h>
  14
  15 #include <asm/feature-fixups.h>
  16
  17 #define JUMP_ENTRY_TYPE         stringify_in_c(FTR_ENTRY_LONG)
  18 #define JUMP_LABEL_NOP_SIZE     4
  19
  20 static __always_inline bool arch_static_branch(struct static_key *key)
  21 {
  22         asm_volatile_goto("1:\n\t"
  23                  "nop\n\t"
  24                  ".pushsection __jump_table,  \"aw\"\n\t"
  25                  JUMP_ENTRY_TYPE "1b, %l[l_yes], %c0\n\t"
  26                  ".popsection \n\t"
  27                  : :  "i" (key) : : l_yes);
  28         return false;
  29 l_yes:
  30         return true;
  31 }
  32
  33 #ifdef CONFIG_PPC64
  34 typedef u64 jump_label_t;
  35 #else
  36 typedef u32 jump_label_t;
  37 #endif
  38
  39 struct jump_entry {
  40         jump_label_t code;
  41         jump_label_t target;
  42         jump_label_t key;
  43 };
  44
  45 #endif /* _ASM_POWERPC_JUMP_LABEL_H */