kernel/trace/trace_export.c

   1 /*
   2  * trace_export.c - export basic ftrace utilities to user space
   3  *
   4  * Copyright (C) 2009 Steven Rostedt <srostedt@redhat.com>
   5  */
   6 #include <linux/stringify.h>
   7 #include <linux/kallsyms.h>
   8 #include <linux/seq_file.h>
   9 #include <linux/debugfs.h>
  10 #include <linux/uaccess.h>
  11 #include <linux/ftrace.h>
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/fs.h>
  15
  16 #include "trace_output.h"
  17
  18
  19 #undef TRACE_STRUCT
  20 #define TRACE_STRUCT(args...) args
  21
  22 #undef TRACE_FIELD
  23 #define TRACE_FIELD(type, item, assign)                                 \
  24         ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"      \
  25                                "offset:%u;\tsize:%u;\n",                \
  26                                (unsigned int)offsetof(typeof(field), item), \
  27                                (unsigned int)sizeof(field.item));       \
  28         if (!ret)                                                       \
  29                 return 0;
  30
  31
  32 #undef TRACE_FIELD_SPECIAL
  33 #define TRACE_FIELD_SPECIAL(type_item, item, len, cmd)                  \
  34         ret = trace_seq_printf(s, "\tfield special:" #type_item ";\t"   \
  35                                "offset:%u;\tsize:%u;\n",                \
  36                                (unsigned int)offsetof(typeof(field), item), \
  37                                (unsigned int)sizeof(field.item));       \
  38         if (!ret)                                                       \
  39                 return 0;
  40
  41 #undef TRACE_FIELD_ZERO_CHAR
  42 #define TRACE_FIELD_ZERO_CHAR(item)                                     \
  43         ret = trace_seq_printf(s, "\tfield:char " #item ";\t"           \
  44                                "offset:%u;\tsize:0;\n",                 \
  45                                (unsigned int)offsetof(typeof(field), item)); \
  46         if (!ret)                                                       \
  47                 return 0;
  48
  49
  50 #undef TP_RAW_FMT
  51 #define TP_RAW_FMT(args...) args
  52
  53 #undef TRACE_EVENT_FORMAT
  54 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)      \
  55 static int                                                              \
  56 ftrace_format_##call(struct trace_seq *s)                               \
  57 {                                                                       \
  58         struct args field;                                              \
  59         int ret;                                                        \
  60                                                                         \
  61         tstruct;                                                        \
  62                                                                         \
  63         trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt);            \
  64                                                                         \
  65         return ret;                                                     \
  66 }
  67
  68 #include "trace_event_types.h"
  69
  70 #undef TRACE_ZERO_CHAR
  71 #define TRACE_ZERO_CHAR(arg)
  72
  73 #undef TRACE_FIELD
  74 #define TRACE_FIELD(type, item, assign)\
  75         entry->item = assign;
  76
  77 #undef TRACE_FIELD
  78 #define TRACE_FIELD(type, item, assign)\
  79         entry->item = assign;
  80
  81 #undef TP_CMD
  82 #define TP_CMD(cmd...)  cmd
  83
  84 #undef TRACE_ENTRY
  85 #define TRACE_ENTRY     entry
  86
  87 #undef TRACE_FIELD_SPECIAL
  88 #define TRACE_FIELD_SPECIAL(type_item, item, len, cmd)  \
  89         cmd;
  90
  91 #undef TRACE_EVENT_FORMAT
  92 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)      \
  93 int ftrace_define_fields_##call(void);                                  \
  94 static int ftrace_raw_init_event_##call(void);                          \
  95                                                                         \
  96 struct ftrace_event_call __used                                         \
  97 __attribute__((__aligned__(4)))                                         \
  98 __attribute__((section("_ftrace_events"))) event_##call = {             \
  99         .name                   = #call,                                \
 100         .id                     = proto,                                \
 101         .system                 = __stringify(TRACE_SYSTEM),            \
 102         .raw_init               = ftrace_raw_init_event_##call,         \
 103         .show_format            = ftrace_format_##call,                 \
 104         .define_fields          = ftrace_define_fields_##call,          \
 105 };                                                                      \
 106 static int ftrace_raw_init_event_##call(void)                           \
 107 {                                                                       \
 108         INIT_LIST_HEAD(&event_##call.fields);                           \
 109         return 0;                                                       \
 110 }                                                                       \
 111
 112 #include "trace_event_types.h"
 113
 114 #undef TRACE_FIELD
 115 #define TRACE_FIELD(type, item, assign)                                 \
 116         ret = trace_define_field(event_call, #type, #item,              \
 117                                  offsetof(typeof(field), item),         \
 118                                  sizeof(field.item));                   \
 119         if (ret)                                                        \
 120                 return ret;
 121
 122 #undef TRACE_FIELD_SPECIAL
 123 #define TRACE_FIELD_SPECIAL(type, item, len, cmd)                       \
 124         ret = trace_define_field(event_call, #type "[" #len "]", #item, \
 125                                  offsetof(typeof(field), item),         \
 126                                  sizeof(field.item));                   \
 127         if (ret)                                                        \
 128                 return ret;
 129
 130 #undef TRACE_FIELD_ZERO_CHAR
 131 #define TRACE_FIELD_ZERO_CHAR(item)
 132
 133 #undef TRACE_EVENT_FORMAT
 134 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)      \
 135 int                                                                     \
 136 ftrace_define_fields_##call(void)                                       \
 137 {                                                                       \
 138         struct ftrace_event_call *event_call = &event_##call;           \
 139         struct args field;                                              \
 140         int ret;                                                        \
 141                                                                         \
 142         __common_field(unsigned char, type);                            \
 143         __common_field(unsigned char, flags);                           \
 144         __common_field(unsigned char, preempt_count);                   \
 145         __common_field(int, pid);                                       \
 146         __common_field(int, tgid);                                      \
 147                                                                         \
 148         tstruct;                                                        \
 149                                                                         \
 150         return ret;                                                     \
 151 }
 152
 153 #include "trace_event_types.h"