include/linux/dynamic_debug.h

   1 #ifndef _DYNAMIC_DEBUG_H
   2 #define _DYNAMIC_DEBUG_H
   3
   4 /*
   5  * An instance of this structure is created in a special
   6  * ELF section at every dynamic debug callsite.  At runtime,
   7  * the special section is treated as an array of these.
   8  */
   9 struct _ddebug {
  10         /*
  11          * These fields are used to drive the user interface
  12          * for selecting and displaying debug callsites.
  13          */
  14         const char *modname;
  15         const char *function;
  16         const char *filename;
  17         const char *format;
  18         unsigned int lineno:24;
  19         /*
  20          * The flags field controls the behaviour at the callsite.
  21          * The bits here are changed dynamically when the user
  22          * writes commands to <debugfs>/dynamic_debug/control
  23          */
  24 #define _DPRINTK_FLAGS_PRINT   (1<<0)  /* printk() a message using the format */
  25 #define _DPRINTK_FLAGS_INCL_MODNAME     (1<<1)
  26 #define _DPRINTK_FLAGS_INCL_FUNCNAME    (1<<2)
  27 #define _DPRINTK_FLAGS_INCL_LINENO      (1<<3)
  28 #define _DPRINTK_FLAGS_INCL_TID         (1<<4)
  29 #define _DPRINTK_FLAGS_DEFAULT 0
  30         unsigned int flags:8;
  31         char enabled;
  32 } __attribute__((aligned(8)));
  33
  34
  35 int ddebug_add_module(struct _ddebug *tab, unsigned int n,
  36                                 const char *modname);
  37
  38 #if defined(CONFIG_DYNAMIC_DEBUG)
  39 extern int ddebug_remove_module(const char *mod_name);
  40 extern int __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...)
  41         __attribute__ ((format (printf, 2, 3)));
  42
  43 struct device;
  44
  45 extern int __dynamic_dev_dbg(struct _ddebug *descriptor,
  46                              const struct device *dev,
  47                              const char *fmt, ...)
  48         __attribute__ ((format (printf, 3, 4)));
  49
  50 struct net_device;
  51
  52 extern int __dynamic_netdev_dbg(struct _ddebug *descriptor,
  53                              const struct net_device *dev,
  54                              const char *fmt, ...)
  55         __attribute__ ((format (printf, 3, 4)));
  56
  57 #define dynamic_pr_debug(fmt, ...) do {                                 \
  58         static struct _ddebug descriptor                                \
  59         __used                                                          \
  60         __attribute__((section("__verbose"), aligned(8))) =             \
  61         { KBUILD_MODNAME, __func__, __FILE__, fmt, __LINE__,            \
  62                 _DPRINTK_FLAGS_DEFAULT };                               \
  63         if (unlikely(descriptor.enabled))                               \
  64                 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__); \
  65         } while (0)
  66
  67 #define dynamic_dev_dbg(dev, fmt, ...) do {                             \
  68         static struct _ddebug descriptor                                \
  69         __used                                                          \
  70         __attribute__((section("__verbose"), aligned(8))) =             \
  71         { KBUILD_MODNAME, __func__, __FILE__, fmt, __LINE__,            \
  72                 _DPRINTK_FLAGS_DEFAULT };                               \
  73         if (unlikely(descriptor.enabled))                               \
  74                 __dynamic_dev_dbg(&descriptor, dev, fmt, ##__VA_ARGS__);        \
  75         } while (0)
  76
  77 #define dynamic_netdev_dbg(dev, fmt, ...) do {                          \
  78         static struct _ddebug descriptor                                \
  79         __used                                                          \
  80         __attribute__((section("__verbose"), aligned(8))) =             \
  81         { KBUILD_MODNAME, __func__, __FILE__, fmt, __LINE__,            \
  82                 _DPRINTK_FLAGS_DEFAULT };                               \
  83         if (unlikely(descriptor.enabled))                               \
  84                 __dynamic_netdev_dbg(&descriptor, dev, fmt, ##__VA_ARGS__);\
  85         } while (0)
  86
  87 #else
  88
  89 static inline int ddebug_remove_module(const char *mod)
  90 {
  91         return 0;
  92 }
  93
  94 #define dynamic_pr_debug(fmt, ...)                                      \
  95         do { if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); } while (0)
  96 #define dynamic_dev_dbg(dev, fmt, ...)                                  \
  97         do { if (0) dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); } while (0)
  98 #endif
  99
 100 #endif