include/linux/ftrace.h

   1 #ifndef _LINUX_FTRACE_H
   2 #define _LINUX_FTRACE_H
   3
   4 #ifdef CONFIG_FTRACE
   5
   6 #include <linux/linkage.h>
   7 #include <linux/fs.h>
   8
   9 extern int ftrace_enabled;
  10 extern int
  11 ftrace_enable_sysctl(struct ctl_table *table, int write,
  12                      struct file *filp, void __user *buffer, size_t *lenp,
  13                      loff_t *ppos);
  14
  15 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip);
  16
  17 struct ftrace_ops {
  18         ftrace_func_t     func;
  19         struct ftrace_ops *next;
  20 };
  21
  22 /*
  23  * The ftrace_ops must be a static and should also
  24  * be read_mostly.  These functions do modify read_mostly variables
  25  * so use them sparely. Never free an ftrace_op or modify the
  26  * next pointer after it has been registered. Even after unregistering
  27  * it, the next pointer may still be used internally.
  28  */
  29 int register_ftrace_function(struct ftrace_ops *ops);
  30 int unregister_ftrace_function(struct ftrace_ops *ops);
  31 void clear_ftrace_function(void);
  32
  33 extern void ftrace_stub(unsigned long a0, unsigned long a1);
  34
  35 #else /* !CONFIG_FTRACE */
  36 # define register_ftrace_function(ops) do { } while (0)
  37 # define unregister_ftrace_function(ops) do { } while (0)
  38 # define clear_ftrace_function(ops) do { } while (0)
  39 #endif /* CONFIG_FTRACE */
  40
  41 #ifdef CONFIG_DYNAMIC_FTRACE
  42 # define FTRACE_HASHBITS        10
  43 # define FTRACE_HASHSIZE        (1<<FTRACE_HASHBITS)
  44
  45 enum {
  46         FTRACE_FL_FREE          = (1 << 0),
  47         FTRACE_FL_FAILED        = (1 << 1),
  48         FTRACE_FL_FILTER        = (1 << 2),
  49         FTRACE_FL_ENABLED       = (1 << 3),
  50         FTRACE_FL_NOTRACE       = (1 << 4),
  51         FTRACE_FL_CONVERTED     = (1 << 5),
  52         FTRACE_FL_FROZEN        = (1 << 6),
  53 };
  54
  55 struct dyn_ftrace {
  56         struct hlist_node node;
  57         unsigned long     ip; /* address of mcount call-site */
  58         unsigned long     flags;
  59 };
  60
  61 int ftrace_force_update(void);
  62 void ftrace_set_filter(unsigned char *buf, int len, int reset);
  63
  64 /* defined in arch */
  65 extern int ftrace_ip_converted(unsigned long ip);
  66 extern unsigned char *ftrace_nop_replace(void);
  67 extern unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr);
  68 extern int ftrace_dyn_arch_init(void *data);
  69 extern int ftrace_mcount_set(unsigned long *data);
  70 extern int ftrace_modify_code(unsigned long ip, unsigned char *old_code,
  71                               unsigned char *new_code);
  72 extern int ftrace_update_ftrace_func(ftrace_func_t func);
  73 extern void ftrace_caller(void);
  74 extern void ftrace_call(void);
  75 extern void mcount_call(void);
  76
  77 extern int skip_trace(unsigned long ip);
  78
  79 void ftrace_disable_daemon(void);
  80 void ftrace_enable_daemon(void);
  81
  82 #else
  83 # define skip_trace(ip)                         ({ 0; })
  84 # define ftrace_force_update()                  ({ 0; })
  85 # define ftrace_set_filter(buf, len, reset)     do { } while (0)
  86 # define ftrace_disable_daemon()                do { } while (0)
  87 # define ftrace_enable_daemon()                 do { } while (0)
  88 #endif /* CONFIG_DYNAMIC_FTRACE */
  89
  90 /* totally disable ftrace - can not re-enable after this */
  91 void ftrace_kill(void);
  92 void ftrace_kill_atomic(void);
  93
  94 static inline void tracer_disable(void)
  95 {
  96 #ifdef CONFIG_FTRACE
  97         ftrace_enabled = 0;
  98 #endif
  99 }
 100
 101 /* Ftrace disable/restore without lock. Some synchronization mechanism
 102  * must be used to prevent ftrace_enabled to be changed between
 103  * disable/restore. */
 104 static inline int __ftrace_enabled_save(void)
 105 {
 106 #ifdef CONFIG_FTRACE
 107         int saved_ftrace_enabled = ftrace_enabled;
 108         ftrace_enabled = 0;
 109         return saved_ftrace_enabled;
 110 #else
 111         return 0;
 112 #endif
 113 }
 114
 115 static inline void __ftrace_enabled_restore(int enabled)
 116 {
 117 #ifdef CONFIG_FTRACE
 118         ftrace_enabled = enabled;
 119 #endif
 120 }
 121
 122 #ifdef CONFIG_FRAME_POINTER
 123 /* TODO: need to fix this for ARM */
 124 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
 125 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
 126 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
 127 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
 128 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
 129 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
 130 # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6))
 131 #else
 132 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
 133 # define CALLER_ADDR1 0UL
 134 # define CALLER_ADDR2 0UL
 135 # define CALLER_ADDR3 0UL
 136 # define CALLER_ADDR4 0UL
 137 # define CALLER_ADDR5 0UL
 138 # define CALLER_ADDR6 0UL
 139 #endif
 140
 141 #ifdef CONFIG_IRQSOFF_TRACER
 142   extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
 143   extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
 144 #else
 145 # define time_hardirqs_on(a0, a1)               do { } while (0)
 146 # define time_hardirqs_off(a0, a1)              do { } while (0)
 147 #endif
 148
 149 #ifdef CONFIG_PREEMPT_TRACER
 150   extern void trace_preempt_on(unsigned long a0, unsigned long a1);
 151   extern void trace_preempt_off(unsigned long a0, unsigned long a1);
 152 #else
 153 # define trace_preempt_on(a0, a1)               do { } while (0)
 154 # define trace_preempt_off(a0, a1)              do { } while (0)
 155 #endif
 156
 157 #ifdef CONFIG_TRACING
 158 extern void
 159 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
 160 #else
 161 static inline void
 162 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
 163 #endif
 164
 165 #endif /* _LINUX_FTRACE_H */