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   1 /*
   2  * Stage 1 of the trace events.
   3  *
   4  * Override the macros in <trace/trace_events.h> to include the following:
   5  *
   6  * struct ftrace_raw_<call> {
   7  *      struct trace_entry              ent;
   8  *      <type>                          <item>;
   9  *      <type2>                         <item2>[<len>];
  10  *      [...]
  11  * };
  12  *
  13  * The <type> <item> is created by the __field(type, item) macro or
  14  * the __array(type2, item2, len) macro.
  15  * We simply do "type item;", and that will create the fields
  16  * in the structure.
  17  */
  18
  19 #include <linux/ftrace_event.h>
  20
  21 #undef __array
  22 #define __array(type, item, len)        type    item[len];
  23
  24 #undef __field
  25 #define __field(type, item)             type    item;
  26
  27 #undef __string
  28 #define __string(item, src)             int     __str_loc_##item;
  29
  30 #undef TP_STRUCT__entry
  31 #define TP_STRUCT__entry(args...) args
  32
  33 #undef TRACE_EVENT
  34 #define TRACE_EVENT(name, proto, args, tstruct, assign, print)  \
  35         struct ftrace_raw_##name {                              \
  36                 struct trace_entry      ent;                    \
  37                 tstruct                                         \
  38                 char                    __str_data[0];          \
  39         };                                                      \
  40         static struct ftrace_event_call event_##name
  41
  42 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
  43
  44
  45 /*
  46  * Stage 2 of the trace events.
  47  *
  48  * Include the following:
  49  *
  50  * struct ftrace_str_offsets_<call> {
  51  *      int                             <str1>;
  52  *      int                             <str2>;
  53  *      [...]
  54  * };
  55  *
  56  * The __string() macro will create each int <str>, this is to
  57  * keep the offset of each string from the beggining of the event
  58  * once we perform the strlen() of the src strings.
  59  *
  60  */
  61
  62 #undef __array
  63 #define __array(type, item, len)
  64
  65 #undef __field
  66 #define __field(type, item);
  67
  68 #undef __string
  69 #define __string(item, src)     int item;
  70
  71 #undef TRACE_EVENT
  72 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
  73         struct ftrace_str_offsets_##call {                              \
  74                 tstruct;                                                \
  75         };
  76
  77 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
  78
  79 /*
  80  * Stage 3 of the trace events.
  81  *
  82  * Override the macros in <trace/trace_events.h> to include the following:
  83  *
  84  * enum print_line_t
  85  * ftrace_raw_output_<call>(struct trace_iterator *iter, int flags)
  86  * {
  87  *      struct trace_seq *s = &iter->seq;
  88  *      struct ftrace_raw_<call> *field; <-- defined in stage 1
  89  *      struct trace_entry *entry;
  90  *      int ret;
  91  *
  92  *      entry = iter->ent;
  93  *
  94  *      if (entry->type != event_<call>.id) {
  95  *              WARN_ON_ONCE(1);
  96  *              return TRACE_TYPE_UNHANDLED;
  97  *      }
  98  *
  99  *      field = (typeof(field))entry;
 100  *
 101  *      ret = trace_seq_printf(s, <TP_printk> "\n");
 102  *      if (!ret)
 103  *              return TRACE_TYPE_PARTIAL_LINE;
 104  *
 105  *      return TRACE_TYPE_HANDLED;
 106  * }
 107  *
 108  * This is the method used to print the raw event to the trace
 109  * output format. Note, this is not needed if the data is read
 110  * in binary.
 111  */
 112
 113 #undef __entry
 114 #define __entry field
 115
 116 #undef TP_printk
 117 #define TP_printk(fmt, args...) fmt "\n", args
 118
 119 #undef __get_str
 120 #define __get_str(field)        ((char *)__entry + __entry->__str_loc_##field)
 121
 122 #undef TRACE_EVENT
 123 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
 124 enum print_line_t                                                       \
 125 ftrace_raw_output_##call(struct trace_iterator *iter, int flags)        \
 126 {                                                                       \
 127         struct trace_seq *s = &iter->seq;                               \
 128         struct ftrace_raw_##call *field;                                \
 129         struct trace_entry *entry;                                      \
 130         int ret;                                                        \
 131                                                                         \
 132         entry = iter->ent;                                              \
 133                                                                         \
 134         if (entry->type != event_##call.id) {                           \
 135                 WARN_ON_ONCE(1);                                        \
 136                 return TRACE_TYPE_UNHANDLED;                            \
 137         }                                                               \
 138                                                                         \
 139         field = (typeof(field))entry;                                   \
 140                                                                         \
 141         ret = trace_seq_printf(s, #call ": " print);                    \
 142         if (!ret)                                                       \
 143                 return TRACE_TYPE_PARTIAL_LINE;                         \
 144                                                                         \
 145         return TRACE_TYPE_HANDLED;                                      \
 146 }
 147
 148 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 149
 150 /*
 151  * Setup the showing format of trace point.
 152  *
 153  * int
 154  * ftrace_format_##call(struct trace_seq *s)
 155  * {
 156  *      struct ftrace_raw_##call field;
 157  *      int ret;
 158  *
 159  *      ret = trace_seq_printf(s, #type " " #item ";"
 160  *                             " offset:%u; size:%u;\n",
 161  *                             offsetof(struct ftrace_raw_##call, item),
 162  *                             sizeof(field.type));
 163  *
 164  * }
 165  */
 166
 167 #undef TP_STRUCT__entry
 168 #define TP_STRUCT__entry(args...) args
 169
 170 #undef __field
 171 #define __field(type, item)                                     \
 172         ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"      \
 173                                "offset:%u;\tsize:%u;\n",                \
 174                                (unsigned int)offsetof(typeof(field), item), \
 175                                (unsigned int)sizeof(field.item));       \
 176         if (!ret)                                                       \
 177                 return 0;
 178
 179 #undef __array
 180 #define __array(type, item, len)                                                \
 181         ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t"    \
 182                                "offset:%u;\tsize:%u;\n",                \
 183                                (unsigned int)offsetof(typeof(field), item), \
 184                                (unsigned int)sizeof(field.item));       \
 185         if (!ret)                                                       \
 186                 return 0;
 187
 188 #undef __string
 189 #define __string(item, src)                                                    \
 190         ret = trace_seq_printf(s, "\tfield: __str_loc " #item ";\t"            \
 191                                "offset:%u;tsize:%u;\n",                        \
 192                                (unsigned int)offsetof(typeof(field),           \
 193                                         __str_loc_##item),                     \
 194                                (unsigned int)sizeof(field.__str_loc_##item));  \
 195         if (!ret)                                                              \
 196                 return 0;
 197
 198 #undef __entry
 199 #define __entry REC
 200
 201 #undef TP_printk
 202 #define TP_printk(fmt, args...) "%s, %s\n", #fmt, __stringify(args)
 203
 204 #undef TP_fast_assign
 205 #define TP_fast_assign(args...) args
 206
 207 #undef TRACE_EVENT
 208 #define TRACE_EVENT(call, proto, args, tstruct, func, print)            \
 209 static int                                                              \
 210 ftrace_format_##call(struct trace_seq *s)                               \
 211 {                                                                       \
 212         struct ftrace_raw_##call field __attribute__((unused));         \
 213         int ret = 0;                                                    \
 214                                                                         \
 215         tstruct;                                                        \
 216                                                                         \
 217         trace_seq_printf(s, "\nprint fmt: " print);                     \
 218                                                                         \
 219         return ret;                                                     \
 220 }
 221
 222 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 223
 224 #undef __field
 225 #define __field(type, item)                                             \
 226         ret = trace_define_field(event_call, #type, #item,              \
 227                                  offsetof(typeof(field), item),         \
 228                                  sizeof(field.item), is_signed_type(type));     \
 229         if (ret)                                                        \
 230                 return ret;
 231
 232 #undef __array
 233 #define __array(type, item, len)                                        \
 234         BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);                         \
 235         ret = trace_define_field(event_call, #type "[" #len "]", #item, \
 236                                  offsetof(typeof(field), item),         \
 237                                  sizeof(field.item), 0);                \
 238         if (ret)                                                        \
 239                 return ret;
 240
 241 #undef __string
 242 #define __string(item, src)                                                    \
 243         ret = trace_define_field(event_call, "__str_loc", #item,               \
 244                                 offsetof(typeof(field), __str_loc_##item),     \
 245                                  sizeof(field.__str_loc_##item), 0);
 246
 247 #undef TRACE_EVENT
 248 #define TRACE_EVENT(call, proto, args, tstruct, func, print)            \
 249 int                                                                     \
 250 ftrace_define_fields_##call(void)                                       \
 251 {                                                                       \
 252         struct ftrace_raw_##call field;                                 \
 253         struct ftrace_event_call *event_call = &event_##call;           \
 254         int ret;                                                        \
 255                                                                         \
 256         __common_field(int, type, 1);                                   \
 257         __common_field(unsigned char, flags, 0);                        \
 258         __common_field(unsigned char, preempt_count, 0);                \
 259         __common_field(int, pid, 1);                                    \
 260         __common_field(int, tgid, 1);                                   \
 261                                                                         \
 262         tstruct;                                                        \
 263                                                                         \
 264         return ret;                                                     \
 265 }
 266
 267 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 268
 269 /*
 270  * Stage 4 of the trace events.
 271  *
 272  * Override the macros in <trace/trace_events.h> to include the following:
 273  *
 274  * static void ftrace_event_<call>(proto)
 275  * {
 276  *      event_trace_printk(_RET_IP_, "<call>: " <fmt>);
 277  * }
 278  *
 279  * static int ftrace_reg_event_<call>(void)
 280  * {
 281  *      int ret;
 282  *
 283  *      ret = register_trace_<call>(ftrace_event_<call>);
 284  *      if (!ret)
 285  *              pr_info("event trace: Could not activate trace point "
 286  *                      "probe to  <call>");
 287  *      return ret;
 288  * }
 289  *
 290  * static void ftrace_unreg_event_<call>(void)
 291  * {
 292  *      unregister_trace_<call>(ftrace_event_<call>);
 293  * }
 294  *
 295  *
 296  * For those macros defined with TRACE_EVENT:
 297  *
 298  * static struct ftrace_event_call event_<call>;
 299  *
 300  * static void ftrace_raw_event_<call>(proto)
 301  * {
 302  *      struct ring_buffer_event *event;
 303  *      struct ftrace_raw_<call> *entry; <-- defined in stage 1
 304  *      unsigned long irq_flags;
 305  *      int pc;
 306  *
 307  *      local_save_flags(irq_flags);
 308  *      pc = preempt_count();
 309  *
 310  *      event = trace_current_buffer_lock_reserve(event_<call>.id,
 311  *                                sizeof(struct ftrace_raw_<call>),
 312  *                                irq_flags, pc);
 313  *      if (!event)
 314  *              return;
 315  *      entry   = ring_buffer_event_data(event);
 316  *
 317  *      <assign>;  <-- Here we assign the entries by the __field and
 318  *                      __array macros.
 319  *
 320  *      trace_current_buffer_unlock_commit(event, irq_flags, pc);
 321  * }
 322  *
 323  * static int ftrace_raw_reg_event_<call>(void)
 324  * {
 325  *      int ret;
 326  *
 327  *      ret = register_trace_<call>(ftrace_raw_event_<call>);
 328  *      if (!ret)
 329  *              pr_info("event trace: Could not activate trace point "
 330  *                      "probe to <call>");
 331  *      return ret;
 332  * }
 333  *
 334  * static void ftrace_unreg_event_<call>(void)
 335  * {
 336  *      unregister_trace_<call>(ftrace_raw_event_<call>);
 337  * }
 338  *
 339  * static struct trace_event ftrace_event_type_<call> = {
 340  *      .trace                  = ftrace_raw_output_<call>, <-- stage 2
 341  * };
 342  *
 343  * static int ftrace_raw_init_event_<call>(void)
 344  * {
 345  *      int id;
 346  *
 347  *      id = register_ftrace_event(&ftrace_event_type_<call>);
 348  *      if (!id)
 349  *              return -ENODEV;
 350  *      event_<call>.id = id;
 351  *      return 0;
 352  * }
 353  *
 354  * static struct ftrace_event_call __used
 355  * __attribute__((__aligned__(4)))
 356  * __attribute__((section("_ftrace_events"))) event_<call> = {
 357  *      .name                   = "<call>",
 358  *      .system                 = "<system>",
 359  *      .raw_init               = ftrace_raw_init_event_<call>,
 360  *      .regfunc                = ftrace_reg_event_<call>,
 361  *      .unregfunc              = ftrace_unreg_event_<call>,
 362  *      .show_format            = ftrace_format_<call>,
 363  * }
 364  *
 365  */
 366
 367 #undef TP_FMT
 368 #define TP_FMT(fmt, args...)    fmt "\n", ##args
 369
 370 #ifdef CONFIG_EVENT_PROFILE
 371 #define _TRACE_PROFILE(call, proto, args)                               \
 372 static void ftrace_profile_##call(proto)                                \
 373 {                                                                       \
 374         extern void perf_tpcounter_event(int);                          \
 375         perf_tpcounter_event(event_##call.id);                          \
 376 }                                                                       \
 377                                                                         \
 378 static int ftrace_profile_enable_##call(struct ftrace_event_call *call) \
 379 {                                                                       \
 380         int ret = 0;                                                    \
 381                                                                         \
 382         if (!atomic_inc_return(&call->profile_count))                   \
 383                 ret = register_trace_##call(ftrace_profile_##call);     \
 384                                                                         \
 385         return ret;                                                     \
 386 }                                                                       \
 387                                                                         \
 388 static void ftrace_profile_disable_##call(struct ftrace_event_call *call) \
 389 {                                                                       \
 390         if (atomic_add_negative(-1, &call->profile_count))              \
 391                 unregister_trace_##call(ftrace_profile_##call);         \
 392 }
 393
 394 #define _TRACE_PROFILE_INIT(call)                                       \
 395         .profile_count = ATOMIC_INIT(-1),                               \
 396         .profile_enable = ftrace_profile_enable_##call,                 \
 397         .profile_disable = ftrace_profile_disable_##call,
 398
 399 #else
 400 #define _TRACE_PROFILE(call, proto, args)
 401 #define _TRACE_PROFILE_INIT(call)
 402 #endif
 403
 404 #undef __entry
 405 #define __entry entry
 406
 407 #undef __field
 408 #define __field(type, item)
 409
 410 #undef __array
 411 #define __array(type, item, len)
 412
 413 #undef __string
 414 #define __string(item, src)                                                    \
 415         __str_offsets.item = __str_size +                                      \
 416                              offsetof(typeof(*entry), __str_data);             \
 417         __str_size += strlen(src) + 1;
 418
 419 #undef __assign_str
 420 #define __assign_str(dst, src)                                          \
 421         __entry->__str_loc_##dst = __str_offsets.dst;                   \
 422         strcpy(__get_str(dst), src);
 423
 424 #undef TRACE_EVENT
 425 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
 426 _TRACE_PROFILE(call, PARAMS(proto), PARAMS(args))                       \
 427                                                                         \
 428 static struct ftrace_event_call event_##call;                           \
 429                                                                         \
 430 static void ftrace_raw_event_##call(proto)                              \
 431 {                                                                       \
 432         struct ftrace_str_offsets_##call __maybe_unused __str_offsets;  \
 433         struct ftrace_event_call *call = &event_##call;                 \
 434         struct ring_buffer_event *event;                                \
 435         struct ftrace_raw_##call *entry;                                \
 436         unsigned long irq_flags;                                        \
 437         int __str_size = 0;                                             \
 438         int pc;                                                         \
 439                                                                         \
 440         local_save_flags(irq_flags);                                    \
 441         pc = preempt_count();                                           \
 442                                                                         \
 443         tstruct;                                                        \
 444                                                                         \
 445         event = trace_current_buffer_lock_reserve(event_##call.id,      \
 446                                  sizeof(struct ftrace_raw_##call) + __str_size,\
 447                                  irq_flags, pc);                        \
 448         if (!event)                                                     \
 449                 return;                                                 \
 450         entry   = ring_buffer_event_data(event);                        \
 451                                                                         \
 452         assign;                                                         \
 453                                                                         \
 454         if (!filter_current_check_discard(call, entry, event))          \
 455                 trace_nowake_buffer_unlock_commit(event, irq_flags, pc); \
 456 }                                                                       \
 457                                                                         \
 458 static int ftrace_raw_reg_event_##call(void)                            \
 459 {                                                                       \
 460         int ret;                                                        \
 461                                                                         \
 462         ret = register_trace_##call(ftrace_raw_event_##call);           \
 463         if (ret)                                                        \
 464                 pr_info("event trace: Could not activate trace point "  \
 465                         "probe to " #call "\n");                        \
 466         return ret;                                                     \
 467 }                                                                       \
 468                                                                         \
 469 static void ftrace_raw_unreg_event_##call(void)                         \
 470 {                                                                       \
 471         unregister_trace_##call(ftrace_raw_event_##call);               \
 472 }                                                                       \
 473                                                                         \
 474 static struct trace_event ftrace_event_type_##call = {                  \
 475         .trace                  = ftrace_raw_output_##call,             \
 476 };                                                                      \
 477                                                                         \
 478 static int ftrace_raw_init_event_##call(void)                           \
 479 {                                                                       \
 480         int id;                                                         \
 481                                                                         \
 482         id = register_ftrace_event(&ftrace_event_type_##call);          \
 483         if (!id)                                                        \
 484                 return -ENODEV;                                         \
 485         event_##call.id = id;                                           \
 486         INIT_LIST_HEAD(&event_##call.fields);                           \
 487         init_preds(&event_##call);                                      \
 488         return 0;                                                       \
 489 }                                                                       \
 490                                                                         \
 491 static struct ftrace_event_call __used                                  \
 492 __attribute__((__aligned__(4)))                                         \
 493 __attribute__((section("_ftrace_events"))) event_##call = {             \
 494         .name                   = #call,                                \
 495         .system                 = __stringify(TRACE_SYSTEM),            \
 496         .event                  = &ftrace_event_type_##call,            \
 497         .raw_init               = ftrace_raw_init_event_##call,         \
 498         .regfunc                = ftrace_raw_reg_event_##call,          \
 499         .unregfunc              = ftrace_raw_unreg_event_##call,        \
 500         .show_format            = ftrace_format_##call,                 \
 501         .define_fields          = ftrace_define_fields_##call,          \
 502         _TRACE_PROFILE_INIT(call)                                       \
 503 }
 504
 505 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 506
 507 #undef _TRACE_PROFILE
 508 #undef _TRACE_PROFILE_INIT
 509