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
   8 extern int ftrace_enabled;
   9 extern int
  10 ftrace_enable_sysctl(struct ctl_table *table, int write,
  11                      struct file *filp, void __user *buffer, size_t *lenp,
  12                      loff_t *ppos);
  13
  14 typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip);
  15
  16 struct ftrace_ops {
  17         ftrace_func_t     func;
  18         struct ftrace_ops *next;
  19 };
  20
  21 /*
  22  * The ftrace_ops must be a static and should also
  23  * be read_mostly.  These functions do modify read_mostly variables
  24  * so use them sparely. Never free an ftrace_op or modify the
  25  * next pointer after it has been registered. Even after unregistering
  26  * it, the next pointer may still be used internally.
  27  */
  28 int register_ftrace_function(struct ftrace_ops *ops);
  29 int unregister_ftrace_function(struct ftrace_ops *ops);
  30 void clear_ftrace_function(void);
  31
  32 extern void ftrace_stub(unsigned long a0, unsigned long a1);
  33 extern void mcount(void);
  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 };
  51
  52 struct dyn_ftrace {
  53         struct hlist_node node;
  54         unsigned long     ip;
  55         unsigned long     flags;
  56 };
  57
  58 int ftrace_force_update(void);
  59 void ftrace_set_filter(unsigned char *buf, int len, int reset);
  60
  61 /* defined in arch */
  62 extern int ftrace_ip_converted(unsigned long ip);
  63 extern unsigned char *ftrace_nop_replace(void);
  64 extern unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr);
  65 extern int ftrace_dyn_arch_init(void *data);
  66 extern int ftrace_mcount_set(unsigned long *data);
  67 extern int ftrace_modify_code(unsigned long ip, unsigned char *old_code,
  68                               unsigned char *new_code);
  69 extern int ftrace_update_ftrace_func(ftrace_func_t func);
  70 extern void ftrace_caller(void);
  71 extern void ftrace_call(void);
  72 extern void mcount_call(void);
  73 #else
  74 # define ftrace_force_update()                  ({ 0; })
  75 # define ftrace_set_filter(buf, len, reset)     do { } while (0)
  76 #endif
  77
  78 /* totally disable ftrace - can not re-enable after this */
  79 void ftrace_kill(void);
  80
  81 static inline void tracer_disable(void)
  82 {
  83 #ifdef CONFIG_FTRACE
  84         ftrace_enabled = 0;
  85 #endif
  86 }
  87
  88 #ifdef CONFIG_FRAME_POINTER
  89 /* TODO: need to fix this for ARM */
  90 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
  91 # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1))
  92 # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2))
  93 # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3))
  94 # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4))
  95 # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5))
  96 #else
  97 # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0))
  98 # define CALLER_ADDR1 0UL
  99 # define CALLER_ADDR2 0UL
 100 # define CALLER_ADDR3 0UL
 101 # define CALLER_ADDR4 0UL
 102 # define CALLER_ADDR5 0UL
 103 #endif
 104
 105 #ifdef CONFIG_IRQSOFF_TRACER
 106   extern void notrace time_hardirqs_on(unsigned long a0, unsigned long a1);
 107   extern void notrace time_hardirqs_off(unsigned long a0, unsigned long a1);
 108 #else
 109 # define time_hardirqs_on(a0, a1)               do { } while (0)
 110 # define time_hardirqs_off(a0, a1)              do { } while (0)
 111 #endif
 112
 113 #ifdef CONFIG_PREEMPT_TRACER
 114   extern void notrace trace_preempt_on(unsigned long a0, unsigned long a1);
 115   extern void notrace trace_preempt_off(unsigned long a0, unsigned long a1);
 116 #else
 117 # define trace_preempt_on(a0, a1)               do { } while (0)
 118 # define trace_preempt_off(a0, a1)              do { } while (0)
 119 #endif
 120
 121 #endif /* _LINUX_FTRACE_H */