1 #ifndef _LINUX_JUMP_LABEL_H 2 #define _LINUX_JUMP_LABEL_H 3 4 #include <linux/types.h> 5 #include <linux/compiler.h> 6 7 #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) 8 9 struct jump_label_key { 10 atomic_t enabled; 11 struct jump_entry *entries; 12 #ifdef CONFIG_MODULES 13 struct jump_label_mod *next; 14 #endif 15 }; 16 17 # include <asm/jump_label.h> 18 # define HAVE_JUMP_LABEL 19 #endif /* CC_HAVE_ASM_GOTO && CONFIG_JUMP_LABEL */ 20 21 enum jump_label_type { 22 JUMP_LABEL_DISABLE = 0, 23 JUMP_LABEL_ENABLE, 24 }; 25 26 struct module; 27 28 #ifdef HAVE_JUMP_LABEL 29 30 #ifdef CONFIG_MODULES 31 #define JUMP_LABEL_INIT {ATOMIC_INIT(0), NULL, NULL} 32 #else 33 #define JUMP_LABEL_INIT {ATOMIC_INIT(0), NULL} 34 #endif 35 36 static __always_inline bool static_branch(struct jump_label_key *key) 37 { 38 return arch_static_branch(key); 39 } 40 41 extern struct jump_entry __start___jump_table[]; 42 extern struct jump_entry __stop___jump_table[]; 43 44 extern void jump_label_init(void); 45 extern void jump_label_lock(void); 46 extern void jump_label_unlock(void); 47 extern void arch_jump_label_transform(struct jump_entry *entry, 48 enum jump_label_type type); 49 extern void arch_jump_label_transform_static(struct jump_entry *entry, 50 enum jump_label_type type); 51 extern int jump_label_text_reserved(void *start, void *end); 52 extern void jump_label_inc(struct jump_label_key *key); 53 extern void jump_label_dec(struct jump_label_key *key); 54 extern bool jump_label_enabled(struct jump_label_key *key); 55 extern void jump_label_apply_nops(struct module *mod); 56 57 #else /* !HAVE_JUMP_LABEL */ 58 59 #include <linux/atomic.h> 60 61 #define JUMP_LABEL_INIT {ATOMIC_INIT(0)} 62 63 struct jump_label_key { 64 atomic_t enabled; 65 }; 66 67 static __always_inline void jump_label_init(void) 68 { 69 } 70 71 static __always_inline bool static_branch(struct jump_label_key *key) 72 { 73 if (unlikely(atomic_read(&key->enabled))) 74 return true; 75 return false; 76 } 77 78 static inline void jump_label_inc(struct jump_label_key *key) 79 { 80 atomic_inc(&key->enabled); 81 } 82 83 static inline void jump_label_dec(struct jump_label_key *key) 84 { 85 atomic_dec(&key->enabled); 86 } 87 88 static inline int jump_label_text_reserved(void *start, void *end) 89 { 90 return 0; 91 } 92 93 static inline void jump_label_lock(void) {} 94 static inline void jump_label_unlock(void) {} 95 96 static inline bool jump_label_enabled(struct jump_label_key *key) 97 { 98 return !!atomic_read(&key->enabled); 99 } 100 101 static inline int jump_label_apply_nops(struct module *mod) 102 { 103 return 0; 104 } 105 #endif /* HAVE_JUMP_LABEL */ 106 107 #endif /* _LINUX_JUMP_LABEL_H */ 108