xref: /linux/arch/powerpc/include/asm/jump_label.h (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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 */
46