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 #undef TRACE_SYSTEM
  19 #define TRACE_SYSTEM    ftrace
  20
  21 /* not needed for this file */
  22 #undef __field_struct
  23 #define __field_struct(type, item)
  24
  25 #undef __field
  26 #define __field(type, item)                             type item;
  27
  28 #undef __field_desc
  29 #define __field_desc(type, container, item)             type item;
  30
  31 #undef __array
  32 #define __array(type, item, size)                       type item[size];
  33
  34 #undef __array_desc
  35 #define __array_desc(type, container, item, size)       type item[size];
  36
  37 #undef __dynamic_array
  38 #define __dynamic_array(type, item)                     type item[];
  39
  40 #undef F_STRUCT
  41 #define F_STRUCT(args...)                               args
  42
  43 #undef F_printk
  44 #define F_printk(fmt, args...) fmt, args
  45
  46 #undef FTRACE_ENTRY
  47 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)     \
  48 struct ____ftrace_##name {                                      \
  49         tstruct                                                 \
  50 };                                                              \
  51 static void __used ____ftrace_check_##name(void)                \
  52 {                                                               \
  53         struct ____ftrace_##name *__entry = NULL;               \
  54                                                                 \
  55         /* force cmpile-time check on F_printk() */             \
  56         printk(print);                                          \
  57 }
  58
  59 #undef FTRACE_ENTRY_DUP
  60 #define FTRACE_ENTRY_DUP(name, struct_name, id, tstruct, print) \
  61         FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
  62
  63 #include "trace_entries.h"
  64
  65
  66 #undef __field
  67 #define __field(type, item)                                             \
  68         ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"      \
  69                                "offset:%zu;\tsize:%zu;\n",              \
  70                                offsetof(typeof(field), item),           \
  71                                sizeof(field.item));                     \
  72         if (!ret)                                                       \
  73                 return 0;
  74
  75 #undef __field_desc
  76 #define __field_desc(type, container, item)                             \
  77         ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"      \
  78                                "offset:%zu;\tsize:%zu;\n",              \
  79                                offsetof(typeof(field), container.item), \
  80                                sizeof(field.container.item));           \
  81         if (!ret)                                                       \
  82                 return 0;
  83
  84 #undef __array
  85 #define __array(type, item, len)                                        \
  86         ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t" \
  87                                "offset:%zu;\tsize:%zu;\n",              \
  88                                offsetof(typeof(field), item),   \
  89                                sizeof(field.item));             \
  90         if (!ret)                                                       \
  91                 return 0;
  92
  93 #undef __array_desc
  94 #define __array_desc(type, container, item, len)                        \
  95         ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t" \
  96                                "offset:%zu;\tsize:%zu;\n",              \
  97                                offsetof(typeof(field), container.item), \
  98                                sizeof(field.container.item));           \
  99         if (!ret)                                                       \
 100                 return 0;
 101
 102 #undef __dynamic_array
 103 #define __dynamic_array(type, item)                                     \
 104         ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"      \
 105                                "offset:%zu;\tsize:0;\n",                \
 106                                offsetof(typeof(field), item));          \
 107         if (!ret)                                                       \
 108                 return 0;
 109
 110 #undef F_printk
 111 #define F_printk(fmt, args...) "%s, %s\n", #fmt, __stringify(args)
 112
 113 #undef __entry
 114 #define __entry REC
 115
 116 #undef FTRACE_ENTRY
 117 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)             \
 118 static int                                                              \
 119 ftrace_format_##name(struct ftrace_event_call *unused,                  \
 120                      struct trace_seq *s)                               \
 121 {                                                                       \
 122         struct struct_name field __attribute__((unused));               \
 123         int ret = 0;                                                    \
 124                                                                         \
 125         tstruct;                                                        \
 126                                                                         \
 127         trace_seq_printf(s, "\nprint fmt: " print);                     \
 128                                                                         \
 129         return ret;                                                     \
 130 }
 131
 132 #include "trace_entries.h"
 133
 134
 135 #undef __field
 136 #define __field(type, item)                                             \
 137         ret = trace_define_field(event_call, #type, #item,              \
 138                                  offsetof(typeof(field), item),         \
 139                                  sizeof(field.item),                    \
 140                                  is_signed_type(type), FILTER_OTHER);   \
 141         if (ret)                                                        \
 142                 return ret;
 143
 144 #undef __field_desc
 145 #define __field_desc(type, container, item)     \
 146         ret = trace_define_field(event_call, #type, #item,              \
 147                                  offsetof(typeof(field),                \
 148                                           container.item),              \
 149                                  sizeof(field.container.item),          \
 150                                  is_signed_type(type), FILTER_OTHER);   \
 151         if (ret)                                                        \
 152                 return ret;
 153
 154 #undef __array
 155 #define __array(type, item, len)                                        \
 156         BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);                         \
 157         ret = trace_define_field(event_call, #type "[" #len "]", #item, \
 158                                  offsetof(typeof(field), item),         \
 159                                  sizeof(field.item), 0, FILTER_OTHER);  \
 160         if (ret)                                                        \
 161                 return ret;
 162
 163 #undef __array_desc
 164 #define __array_desc(type, container, item, len)                        \
 165         BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);                         \
 166         ret = trace_define_field(event_call, #type "[" #len "]", #item, \
 167                                  offsetof(typeof(field),                \
 168                                           container.item),              \
 169                                  sizeof(field.container.item), 0,       \
 170                                  FILTER_OTHER);                         \
 171         if (ret)                                                        \
 172                 return ret;
 173
 174 #undef __dynamic_array
 175 #define __dynamic_array(type, item)
 176
 177 #undef FTRACE_ENTRY
 178 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print)             \
 179 int                                                                     \
 180 ftrace_define_fields_##name(struct ftrace_event_call *event_call)       \
 181 {                                                                       \
 182         struct struct_name field;                                       \
 183         int ret;                                                        \
 184                                                                         \
 185         ret = trace_define_common_fields(event_call);                   \
 186         if (ret)                                                        \
 187                 return ret;                                             \
 188                                                                         \
 189         tstruct;                                                        \
 190                                                                         \
 191         return ret;                                                     \
 192 }
 193
 194 #include "trace_entries.h"
 195
 196
 197 #undef __field
 198 #define __field(type, item)
 199
 200 #undef __field_desc
 201 #define __field_desc(type, container, item)
 202
 203 #undef __array
 204 #define __array(type, item, len)
 205
 206 #undef __array_desc
 207 #define __array_desc(type, container, item, len)
 208
 209 #undef __dynamic_array
 210 #define __dynamic_array(type, item)
 211
 212 #undef FTRACE_ENTRY
 213 #define FTRACE_ENTRY(call, struct_name, type, tstruct, print)           \
 214 static int ftrace_raw_init_event_##call(void);                          \
 215                                                                         \
 216 struct ftrace_event_call __used                                         \
 217 __attribute__((__aligned__(4)))                                         \
 218 __attribute__((section("_ftrace_events"))) event_##call = {             \
 219         .name                   = #call,                                \
 220         .id                     = type,                                 \
 221         .system                 = __stringify(TRACE_SYSTEM),            \
 222         .raw_init               = ftrace_raw_init_event_##call,         \
 223         .show_format            = ftrace_format_##call,                 \
 224         .define_fields          = ftrace_define_fields_##call,          \
 225 };                                                                      \
 226 static int ftrace_raw_init_event_##call(void)                           \
 227 {                                                                       \
 228         INIT_LIST_HEAD(&event_##call.fields);                           \
 229         return 0;                                                       \
 230 }                                                                       \
 231
 232 #include "trace_entries.h"