wrapper/ftrace.h

   1 #ifndef _LTT_WRAPPER_FTRACE_H
   2 #define _LTT_WRAPPER_FTRACE_H
   3
   4 /*
   5  * Copyright (C) 2011 Mathieu Desnoyers (mathieu.desnoyers@efficios.com)
   6  *
   7  * wrapper around vmalloc_sync_all. Using KALLSYMS to get its address when
   8  * available, else we need to have a kernel that exports this function to GPL
   9  * modules.
  10  *
  11  * Dual LGPL v2.1/GPL v2 license.
  12  */
  13
  14 #include <linux/ftrace.h>
  15
  16 #ifdef CONFIG_KALLSYMS
  17
  18 #include <linux/kallsyms.h>
  19
  20 static inline
  21 int wrapper_register_ftrace_function_probe(char *glob,
  22                 struct ftrace_probe_ops *ops, void *data)
  23 {
  24         int (*register_ftrace_function_probe_sym)(char *glob,
  25                         struct ftrace_probe_ops *ops, void *data);
  26
  27         register_ftrace_function_probe_sym = (void *) kallsyms_lookup_name("register_ftrace_function_probe");
  28         if (register_ftrace_function_probe_sym) {
  29                 return register_ftrace_function_probe_sym(glob, ops, data);
  30         } else {
  31                 printk(KERN_WARNING "LTTng: register_ftrace_function_probe symbol lookup failed.\n");
  32                 return -EINVAL;
  33         }
  34 }
  35
  36 static inline
  37 void wrapper_unregister_ftrace_function_probe(char *glob,
  38                 struct ftrace_probe_ops *ops, void *data)
  39 {
  40         void (*unregister_ftrace_function_probe_sym)(char *glob,
  41                         struct ftrace_probe_ops *ops, void *data);
  42
  43         unregister_ftrace_function_probe_sym = (void *) kallsyms_lookup_name("unregister_ftrace_function_probe");
  44         if (unregister_ftrace_function_probe_sym) {
  45                 unregister_ftrace_function_probe_sym(glob, ops, data);
  46         } else {
  47                 printk(KERN_WARNING "LTTng: unregister_ftrace_function_probe symbol lookup failed.\n");
  48                 WARN_ON(1);
  49         }
  50 }
  51
  52 #else
  53
  54 static inline
  55 int wrapper_register_ftrace_function_probe(char *glob,
  56                 struct ftrace_probe_ops *ops, void *data)
  57 {
  58         return unregister_ftrace_function_probe();
  59 }
  60
  61 static inline
  62 void wrapper_unregister_ftrace_function_probe(char *glob,
  63                 struct ftrace_probe_ops *ops, void *data)
  64 {
  65         return unregister_ftrace_function_probe();
  66 }
  67 #endif
  68
  69 #endif /* _LTT_WRAPPER_FTRACE_H */