kernel/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 #ifndef __ASSEMBLY__
  14 #include <linux/types.h>
  15
  16 #include <asm/feature-fixups.h>
  17
  18 #define JUMP_ENTRY_TYPE         stringify_in_c(FTR_ENTRY_LONG)
  19 #define JUMP_LABEL_NOP_SIZE     4
  20
  21 static __always_inline bool arch_static_branch(struct static_key *key)
  22 {
  23         asm_volatile_goto("1:\n\t"
  24                  "nop\n\t"
  25                  ".pushsection __jump_table,  \"aw\"\n\t"
  26                  JUMP_ENTRY_TYPE "1b, %l[l_yes], %c0\n\t"
  27                  ".popsection \n\t"
  28                  : :  "i" (key) : : l_yes);
  29         return false;
  30 l_yes:
  31         return true;
  32 }
  33
  34 #ifdef CONFIG_PPC64
  35 typedef u64 jump_label_t;
  36 #else
  37 typedef u32 jump_label_t;
  38 #endif
  39
  40 struct jump_entry {
  41         jump_label_t code;
  42         jump_label_t target;
  43         jump_label_t key;
  44 };
  45
  46 #else
  47 #define ARCH_STATIC_BRANCH(LABEL, KEY)          \
  48 1098:   nop;                                    \
  49         .pushsection __jump_table, "aw";        \
  50         FTR_ENTRY_LONG 1098b, LABEL, KEY;       \
  51         .popsection
  52 #endif
  53
  54 #endif /* _ASM_POWERPC_JUMP_LABEL_H */