include/trace/ftrace.h

   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 __field
  22 #define __field(type, item)             type    item;
  23
  24 #undef __field_ext
  25 #define __field_ext(type, item, filter_type)    type    item;
  26
  27 #undef __array
  28 #define __array(type, item, len)        type    item[len];
  29
  30 #undef __dynamic_array
  31 #define __dynamic_array(type, item, len) u32 __data_loc_##item;
  32
  33 #undef __string
  34 #define __string(item, src) __dynamic_array(char, item, -1)
  35
  36 #undef TP_STRUCT__entry
  37 #define TP_STRUCT__entry(args...) args
  38
  39 #undef TRACE_EVENT
  40 #define TRACE_EVENT(name, proto, args, tstruct, assign, print)  \
  41         struct ftrace_raw_##name {                              \
  42                 struct trace_entry      ent;                    \
  43                 tstruct                                         \
  44                 char                    __data[0];              \
  45         };                                                      \
  46         static struct ftrace_event_call event_##name
  47
  48 #undef __cpparg
  49 #define __cpparg(arg...) arg
  50
  51 /* Callbacks are meaningless to ftrace. */
  52 #undef TRACE_EVENT_FN
  53 #define TRACE_EVENT_FN(name, proto, args, tstruct,                      \
  54                 assign, print, reg, unreg)                              \
  55         TRACE_EVENT(name, __cpparg(proto), __cpparg(args),              \
  56                 __cpparg(tstruct), __cpparg(assign), __cpparg(print))   \
  57
  58 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
  59
  60
  61 /*
  62  * Stage 2 of the trace events.
  63  *
  64  * Include the following:
  65  *
  66  * struct ftrace_data_offsets_<call> {
  67  *      u32                             <item1>;
  68  *      u32                             <item2>;
  69  *      [...]
  70  * };
  71  *
  72  * The __dynamic_array() macro will create each u32 <item>, this is
  73  * to keep the offset of each array from the beginning of the event.
  74  * The size of an array is also encoded, in the higher 16 bits of <item>.
  75  */
  76
  77 #undef __field
  78 #define __field(type, item)
  79
  80 #undef __field_ext
  81 #define __field_ext(type, item, filter_type)
  82
  83 #undef __array
  84 #define __array(type, item, len)
  85
  86 #undef __dynamic_array
  87 #define __dynamic_array(type, item, len)        u32 item;
  88
  89 #undef __string
  90 #define __string(item, src) __dynamic_array(char, item, -1)
  91
  92 #undef TRACE_EVENT
  93 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
  94         struct ftrace_data_offsets_##call {                             \
  95                 tstruct;                                                \
  96         };
  97
  98 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
  99
 100 /*
 101  * Setup the showing format of trace point.
 102  *
 103  * int
 104  * ftrace_format_##call(struct trace_seq *s)
 105  * {
 106  *      struct ftrace_raw_##call field;
 107  *      int ret;
 108  *
 109  *      ret = trace_seq_printf(s, #type " " #item ";"
 110  *                             " offset:%u; size:%u;\n",
 111  *                             offsetof(struct ftrace_raw_##call, item),
 112  *                             sizeof(field.type));
 113  *
 114  * }
 115  */
 116
 117 #undef TP_STRUCT__entry
 118 #define TP_STRUCT__entry(args...) args
 119
 120 #undef __field
 121 #define __field(type, item)                                     \
 122         ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"      \
 123                                "offset:%u;\tsize:%u;\tsigned:%u;\n",    \
 124                                (unsigned int)offsetof(typeof(field), item), \
 125                                (unsigned int)sizeof(field.item),        \
 126                                (unsigned int)is_signed_type(type));     \
 127         if (!ret)                                                       \
 128                 return 0;
 129
 130 #undef __field_ext
 131 #define __field_ext(type, item, filter_type)    __field(type, item)
 132
 133 #undef __array
 134 #define __array(type, item, len)                                                \
 135         ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t"    \
 136                                "offset:%u;\tsize:%u;\tsigned:%u;\n",    \
 137                                (unsigned int)offsetof(typeof(field), item), \
 138                                (unsigned int)sizeof(field.item),        \
 139                                (unsigned int)is_signed_type(type));     \
 140         if (!ret)                                                       \
 141                 return 0;
 142
 143 #undef __dynamic_array
 144 #define __dynamic_array(type, item, len)                                       \
 145         ret = trace_seq_printf(s, "\tfield:__data_loc " #type "[] " #item ";\t"\
 146                                "offset:%u;\tsize:%u;\tsigned:%u;\n",           \
 147                                (unsigned int)offsetof(typeof(field),           \
 148                                         __data_loc_##item),                    \
 149                                (unsigned int)sizeof(field.__data_loc_##item), \
 150                                (unsigned int)is_signed_type(type));     \
 151         if (!ret)                                                              \
 152                 return 0;
 153
 154 #undef __string
 155 #define __string(item, src) __dynamic_array(char, item, -1)
 156
 157 #undef __entry
 158 #define __entry REC
 159
 160 #undef __print_symbolic
 161 #undef __get_dynamic_array
 162 #undef __get_str
 163
 164 #undef TP_printk
 165 #define TP_printk(fmt, args...) "%s, %s\n", #fmt, __stringify(args)
 166
 167 #undef TP_fast_assign
 168 #define TP_fast_assign(args...) args
 169
 170 #undef TP_perf_assign
 171 #define TP_perf_assign(args...)
 172
 173 #undef TRACE_EVENT
 174 #define TRACE_EVENT(call, proto, args, tstruct, func, print)            \
 175 static int                                                              \
 176 ftrace_format_##call(struct ftrace_event_call *unused,                  \
 177                       struct trace_seq *s)                              \
 178 {                                                                       \
 179         struct ftrace_raw_##call field __attribute__((unused));         \
 180         int ret = 0;                                                    \
 181                                                                         \
 182         tstruct;                                                        \
 183                                                                         \
 184         trace_seq_printf(s, "\nprint fmt: " print);                     \
 185                                                                         \
 186         return ret;                                                     \
 187 }
 188
 189 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 190
 191 /*
 192  * Stage 3 of the trace events.
 193  *
 194  * Override the macros in <trace/trace_events.h> to include the following:
 195  *
 196  * enum print_line_t
 197  * ftrace_raw_output_<call>(struct trace_iterator *iter, int flags)
 198  * {
 199  *      struct trace_seq *s = &iter->seq;
 200  *      struct ftrace_raw_<call> *field; <-- defined in stage 1
 201  *      struct trace_entry *entry;
 202  *      struct trace_seq *p;
 203  *      int ret;
 204  *
 205  *      entry = iter->ent;
 206  *
 207  *      if (entry->type != event_<call>.id) {
 208  *              WARN_ON_ONCE(1);
 209  *              return TRACE_TYPE_UNHANDLED;
 210  *      }
 211  *
 212  *      field = (typeof(field))entry;
 213  *
 214  *      p = get_cpu_var(ftrace_event_seq);
 215  *      trace_seq_init(p);
 216  *      ret = trace_seq_printf(s, <TP_printk> "\n");
 217  *      put_cpu();
 218  *      if (!ret)
 219  *              return TRACE_TYPE_PARTIAL_LINE;
 220  *
 221  *      return TRACE_TYPE_HANDLED;
 222  * }
 223  *
 224  * This is the method used to print the raw event to the trace
 225  * output format. Note, this is not needed if the data is read
 226  * in binary.
 227  */
 228
 229 #undef __entry
 230 #define __entry field
 231
 232 #undef TP_printk
 233 #define TP_printk(fmt, args...) fmt "\n", args
 234
 235 #undef __get_dynamic_array
 236 #define __get_dynamic_array(field)      \
 237                 ((void *)__entry + (__entry->__data_loc_##field & 0xffff))
 238
 239 #undef __get_str
 240 #define __get_str(field) (char *)__get_dynamic_array(field)
 241
 242 #undef __print_flags
 243 #define __print_flags(flag, delim, flag_array...)                       \
 244         ({                                                              \
 245                 static const struct trace_print_flags __flags[] =       \
 246                         { flag_array, { -1, NULL }};                    \
 247                 ftrace_print_flags_seq(p, delim, flag, __flags);        \
 248         })
 249
 250 #undef __print_symbolic
 251 #define __print_symbolic(value, symbol_array...)                        \
 252         ({                                                              \
 253                 static const struct trace_print_flags symbols[] =       \
 254                         { symbol_array, { -1, NULL }};                  \
 255                 ftrace_print_symbols_seq(p, value, symbols);            \
 256         })
 257
 258 #undef TRACE_EVENT
 259 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
 260 static enum print_line_t                                                \
 261 ftrace_raw_output_##call(struct trace_iterator *iter, int flags)        \
 262 {                                                                       \
 263         struct trace_seq *s = &iter->seq;                               \
 264         struct ftrace_raw_##call *field;                                \
 265         struct trace_entry *entry;                                      \
 266         struct trace_seq *p;                                            \
 267         int ret;                                                        \
 268                                                                         \
 269         entry = iter->ent;                                              \
 270                                                                         \
 271         if (entry->type != event_##call.id) {                           \
 272                 WARN_ON_ONCE(1);                                        \
 273                 return TRACE_TYPE_UNHANDLED;                            \
 274         }                                                               \
 275                                                                         \
 276         field = (typeof(field))entry;                                   \
 277                                                                         \
 278         p = &get_cpu_var(ftrace_event_seq);                             \
 279         trace_seq_init(p);                                              \
 280         ret = trace_seq_printf(s, #call ": " print);                    \
 281         put_cpu();                                                      \
 282         if (!ret)                                                       \
 283                 return TRACE_TYPE_PARTIAL_LINE;                         \
 284                                                                         \
 285         return TRACE_TYPE_HANDLED;                                      \
 286 }
 287
 288 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 289
 290 #undef __field_ext
 291 #define __field_ext(type, item, filter_type)                            \
 292         ret = trace_define_field(event_call, #type, #item,              \
 293                                  offsetof(typeof(field), item),         \
 294                                  sizeof(field.item),                    \
 295                                  is_signed_type(type), filter_type);    \
 296         if (ret)                                                        \
 297                 return ret;
 298
 299 #undef __field
 300 #define __field(type, item)     __field_ext(type, item, FILTER_OTHER)
 301
 302 #undef __array
 303 #define __array(type, item, len)                                        \
 304         BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);                         \
 305         ret = trace_define_field(event_call, #type "[" #len "]", #item, \
 306                                  offsetof(typeof(field), item),         \
 307                                  sizeof(field.item), 0, FILTER_OTHER);  \
 308         if (ret)                                                        \
 309                 return ret;
 310
 311 #undef __dynamic_array
 312 #define __dynamic_array(type, item, len)                                       \
 313         ret = trace_define_field(event_call, "__data_loc " #type "[]", #item,  \
 314                                  offsetof(typeof(field), __data_loc_##item),   \
 315                                  sizeof(field.__data_loc_##item), 0,           \
 316                                  FILTER_OTHER);
 317
 318 #undef __string
 319 #define __string(item, src) __dynamic_array(char, item, -1)
 320
 321 #undef TRACE_EVENT
 322 #define TRACE_EVENT(call, proto, args, tstruct, func, print)            \
 323 static int                                                              \
 324 ftrace_define_fields_##call(struct ftrace_event_call *event_call)       \
 325 {                                                                       \
 326         struct ftrace_raw_##call field;                                 \
 327         int ret;                                                        \
 328                                                                         \
 329         ret = trace_define_common_fields(event_call);                   \
 330         if (ret)                                                        \
 331                 return ret;                                             \
 332                                                                         \
 333         tstruct;                                                        \
 334                                                                         \
 335         return ret;                                                     \
 336 }
 337
 338 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 339
 340 /*
 341  * remember the offset of each array from the beginning of the event.
 342  */
 343
 344 #undef __entry
 345 #define __entry entry
 346
 347 #undef __field
 348 #define __field(type, item)
 349
 350 #undef __field_ext
 351 #define __field_ext(type, item, filter_type)
 352
 353 #undef __array
 354 #define __array(type, item, len)
 355
 356 #undef __dynamic_array
 357 #define __dynamic_array(type, item, len)                                \
 358         __data_offsets->item = __data_size +                            \
 359                                offsetof(typeof(*entry), __data);        \
 360         __data_offsets->item |= (len * sizeof(type)) << 16;             \
 361         __data_size += (len) * sizeof(type);
 362
 363 #undef __string
 364 #define __string(item, src) __dynamic_array(char, item, strlen(src) + 1)       \
 365
 366 #undef TRACE_EVENT
 367 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
 368 static inline int ftrace_get_offsets_##call(                            \
 369         struct ftrace_data_offsets_##call *__data_offsets, proto)       \
 370 {                                                                       \
 371         int __data_size = 0;                                            \
 372         struct ftrace_raw_##call __maybe_unused *entry;                 \
 373                                                                         \
 374         tstruct;                                                        \
 375                                                                         \
 376         return __data_size;                                             \
 377 }
 378
 379 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 380
 381 #ifdef CONFIG_EVENT_PROFILE
 382
 383 /*
 384  * Generate the functions needed for tracepoint perf_event support.
 385  *
 386  * NOTE: The insertion profile callback (ftrace_profile_<call>) is defined later
 387  *
 388  * static int ftrace_profile_enable_<call>(void)
 389  * {
 390  *      return register_trace_<call>(ftrace_profile_<call>);
 391  * }
 392  *
 393  * static void ftrace_profile_disable_<call>(void)
 394  * {
 395  *      unregister_trace_<call>(ftrace_profile_<call>);
 396  * }
 397  *
 398  */
 399
 400 #undef TRACE_EVENT
 401 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
 402                                                                         \
 403 static void ftrace_profile_##call(proto);                               \
 404                                                                         \
 405 static int ftrace_profile_enable_##call(struct ftrace_event_call *unused)\
 406 {                                                                       \
 407         return register_trace_##call(ftrace_profile_##call);            \
 408 }                                                                       \
 409                                                                         \
 410 static void ftrace_profile_disable_##call(struct ftrace_event_call *unused)\
 411 {                                                                       \
 412         unregister_trace_##call(ftrace_profile_##call);                 \
 413 }
 414
 415 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 416
 417 #endif
 418
 419 /*
 420  * Stage 4 of the trace events.
 421  *
 422  * Override the macros in <trace/trace_events.h> to include the following:
 423  *
 424  * static void ftrace_event_<call>(proto)
 425  * {
 426  *      event_trace_printk(_RET_IP_, "<call>: " <fmt>);
 427  * }
 428  *
 429  * static int ftrace_reg_event_<call>(struct ftrace_event_call *unused)
 430  * {
 431  *      int ret;
 432  *
 433  *      ret = register_trace_<call>(ftrace_event_<call>);
 434  *      if (!ret)
 435  *              pr_info("event trace: Could not activate trace point "
 436  *                      "probe to  <call>");
 437  *      return ret;
 438  * }
 439  *
 440  * static void ftrace_unreg_event_<call>(struct ftrace_event_call *unused)
 441  * {
 442  *      unregister_trace_<call>(ftrace_event_<call>);
 443  * }
 444  *
 445  *
 446  * For those macros defined with TRACE_EVENT:
 447  *
 448  * static struct ftrace_event_call event_<call>;
 449  *
 450  * static void ftrace_raw_event_<call>(proto)
 451  * {
 452  *      struct ring_buffer_event *event;
 453  *      struct ftrace_raw_<call> *entry; <-- defined in stage 1
 454  *      struct ring_buffer *buffer;
 455  *      unsigned long irq_flags;
 456  *      int pc;
 457  *
 458  *      local_save_flags(irq_flags);
 459  *      pc = preempt_count();
 460  *
 461  *      event = trace_current_buffer_lock_reserve(&buffer,
 462  *                                event_<call>.id,
 463  *                                sizeof(struct ftrace_raw_<call>),
 464  *                                irq_flags, pc);
 465  *      if (!event)
 466  *              return;
 467  *      entry   = ring_buffer_event_data(event);
 468  *
 469  *      <assign>;  <-- Here we assign the entries by the __field and
 470  *                      __array macros.
 471  *
 472  *      trace_current_buffer_unlock_commit(buffer, event, irq_flags, pc);
 473  * }
 474  *
 475  * static int ftrace_raw_reg_event_<call>(struct ftrace_event_call *unused)
 476  * {
 477  *      int ret;
 478  *
 479  *      ret = register_trace_<call>(ftrace_raw_event_<call>);
 480  *      if (!ret)
 481  *              pr_info("event trace: Could not activate trace point "
 482  *                      "probe to <call>");
 483  *      return ret;
 484  * }
 485  *
 486  * static void ftrace_unreg_event_<call>(struct ftrace_event_call *unused)
 487  * {
 488  *      unregister_trace_<call>(ftrace_raw_event_<call>);
 489  * }
 490  *
 491  * static struct trace_event ftrace_event_type_<call> = {
 492  *      .trace                  = ftrace_raw_output_<call>, <-- stage 2
 493  * };
 494  *
 495  * static int ftrace_raw_init_event_<call>(struct ftrace_event_call *unused)
 496  * {
 497  *      int id;
 498  *
 499  *      id = register_ftrace_event(&ftrace_event_type_<call>);
 500  *      if (!id)
 501  *              return -ENODEV;
 502  *      event_<call>.id = id;
 503  *      return 0;
 504  * }
 505  *
 506  * static struct ftrace_event_call __used
 507  * __attribute__((__aligned__(4)))
 508  * __attribute__((section("_ftrace_events"))) event_<call> = {
 509  *      .name                   = "<call>",
 510  *      .system                 = "<system>",
 511  *      .raw_init               = ftrace_raw_init_event_<call>,
 512  *      .regfunc                = ftrace_reg_event_<call>,
 513  *      .unregfunc              = ftrace_unreg_event_<call>,
 514  *      .show_format            = ftrace_format_<call>,
 515  * }
 516  *
 517  */
 518
 519 #undef TP_FMT
 520 #define TP_FMT(fmt, args...)    fmt "\n", ##args
 521
 522 #ifdef CONFIG_EVENT_PROFILE
 523
 524 #define _TRACE_PROFILE_INIT(call)                                       \
 525         .profile_count = ATOMIC_INIT(-1),                               \
 526         .profile_enable = ftrace_profile_enable_##call,                 \
 527         .profile_disable = ftrace_profile_disable_##call,
 528
 529 #else
 530 #define _TRACE_PROFILE_INIT(call)
 531 #endif
 532
 533 #undef __entry
 534 #define __entry entry
 535
 536 #undef __field
 537 #define __field(type, item)
 538
 539 #undef __array
 540 #define __array(type, item, len)
 541
 542 #undef __dynamic_array
 543 #define __dynamic_array(type, item, len)                                \
 544         __entry->__data_loc_##item = __data_offsets.item;
 545
 546 #undef __string
 547 #define __string(item, src) __dynamic_array(char, item, -1)             \
 548
 549 #undef __assign_str
 550 #define __assign_str(dst, src)                                          \
 551         strcpy(__get_str(dst), src);
 552
 553 #undef TRACE_EVENT
 554 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
 555                                                                         \
 556 static struct ftrace_event_call event_##call;                           \
 557                                                                         \
 558 static void ftrace_raw_event_##call(proto)                              \
 559 {                                                                       \
 560         struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
 561         struct ftrace_event_call *event_call = &event_##call;           \
 562         struct ring_buffer_event *event;                                \
 563         struct ftrace_raw_##call *entry;                                \
 564         struct ring_buffer *buffer;                                     \
 565         unsigned long irq_flags;                                        \
 566         int __data_size;                                                \
 567         int pc;                                                         \
 568                                                                         \
 569         local_save_flags(irq_flags);                                    \
 570         pc = preempt_count();                                           \
 571                                                                         \
 572         __data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
 573                                                                         \
 574         event = trace_current_buffer_lock_reserve(&buffer,              \
 575                                  event_##call.id,                       \
 576                                  sizeof(*entry) + __data_size,          \
 577                                  irq_flags, pc);                        \
 578         if (!event)                                                     \
 579                 return;                                                 \
 580         entry   = ring_buffer_event_data(event);                        \
 581                                                                         \
 582                                                                         \
 583         tstruct                                                         \
 584                                                                         \
 585         { assign; }                                                     \
 586                                                                         \
 587         if (!filter_current_check_discard(buffer, event_call, entry, event)) \
 588                 trace_nowake_buffer_unlock_commit(buffer,               \
 589                                                   event, irq_flags, pc); \
 590 }                                                                       \
 591                                                                         \
 592 static int ftrace_raw_reg_event_##call(struct ftrace_event_call *unused)\
 593 {                                                                       \
 594         int ret;                                                        \
 595                                                                         \
 596         ret = register_trace_##call(ftrace_raw_event_##call);           \
 597         if (ret)                                                        \
 598                 pr_info("event trace: Could not activate trace point "  \
 599                         "probe to " #call "\n");                        \
 600         return ret;                                                     \
 601 }                                                                       \
 602                                                                         \
 603 static void ftrace_raw_unreg_event_##call(struct ftrace_event_call *unused)\
 604 {                                                                       \
 605         unregister_trace_##call(ftrace_raw_event_##call);               \
 606 }                                                                       \
 607                                                                         \
 608 static struct trace_event ftrace_event_type_##call = {                  \
 609         .trace                  = ftrace_raw_output_##call,             \
 610 };                                                                      \
 611                                                                         \
 612 static int ftrace_raw_init_event_##call(struct ftrace_event_call *unused)\
 613 {                                                                       \
 614         int id;                                                         \
 615                                                                         \
 616         id = register_ftrace_event(&ftrace_event_type_##call);          \
 617         if (!id)                                                        \
 618                 return -ENODEV;                                         \
 619         event_##call.id = id;                                           \
 620         INIT_LIST_HEAD(&event_##call.fields);                           \
 621         return 0;                                                       \
 622 }                                                                       \
 623                                                                         \
 624 static struct ftrace_event_call __used                                  \
 625 __attribute__((__aligned__(4)))                                         \
 626 __attribute__((section("_ftrace_events"))) event_##call = {             \
 627         .name                   = #call,                                \
 628         .system                 = __stringify(TRACE_SYSTEM),            \
 629         .event                  = &ftrace_event_type_##call,            \
 630         .raw_init               = ftrace_raw_init_event_##call,         \
 631         .regfunc                = ftrace_raw_reg_event_##call,          \
 632         .unregfunc              = ftrace_raw_unreg_event_##call,        \
 633         .show_format            = ftrace_format_##call,                 \
 634         .define_fields          = ftrace_define_fields_##call,          \
 635         _TRACE_PROFILE_INIT(call)                                       \
 636 }
 637
 638 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 639
 640 /*
 641  * Define the insertion callback to profile events
 642  *
 643  * The job is very similar to ftrace_raw_event_<call> except that we don't
 644  * insert in the ring buffer but in a perf counter.
 645  *
 646  * static void ftrace_profile_<call>(proto)
 647  * {
 648  *      struct ftrace_data_offsets_<call> __maybe_unused __data_offsets;
 649  *      struct ftrace_event_call *event_call = &event_<call>;
 650  *      extern void perf_tp_event(int, u64, u64, void *, int);
 651  *      struct ftrace_raw_##call *entry;
 652  *      struct perf_trace_buf *trace_buf;
 653  *      u64 __addr = 0, __count = 1;
 654  *      unsigned long irq_flags;
 655  *      struct trace_entry *ent;
 656  *      int __entry_size;
 657  *      int __data_size;
 658  *      int __cpu
 659  *      int pc;
 660  *
 661  *      pc = preempt_count();
 662  *
 663  *      __data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
 664  *
 665  *      // Below we want to get the aligned size by taking into account
 666  *      // the u32 field that will later store the buffer size
 667  *      __entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),
 668  *                           sizeof(u64));
 669  *      __entry_size -= sizeof(u32);
 670  *
 671  *      // Protect the non nmi buffer
 672  *      // This also protects the rcu read side
 673  *      local_irq_save(irq_flags);
 674  *      __cpu = smp_processor_id();
 675  *
 676  *      if (in_nmi())
 677  *              trace_buf = rcu_dereference(perf_trace_buf_nmi);
 678  *      else
 679  *              trace_buf = rcu_dereference(perf_trace_buf);
 680  *
 681  *      if (!trace_buf)
 682  *              goto end;
 683  *
 684  *      trace_buf = per_cpu_ptr(trace_buf, __cpu);
 685  *
 686  *      // Avoid recursion from perf that could mess up the buffer
 687  *      if (trace_buf->recursion++)
 688  *              goto end_recursion;
 689  *
 690  *      raw_data = trace_buf->buf;
 691  *
 692  *      // Make recursion update visible before entering perf_tp_event
 693  *      // so that we protect from perf recursions.
 694  *
 695  *      barrier();
 696  *
 697  *      //zero dead bytes from alignment to avoid stack leak to userspace:
 698  *      *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL;
 699  *      entry = (struct ftrace_raw_<call> *)raw_data;
 700  *      ent = &entry->ent;
 701  *      tracing_generic_entry_update(ent, irq_flags, pc);
 702  *      ent->type = event_call->id;
 703  *
 704  *      <tstruct> <- do some jobs with dynamic arrays
 705  *
 706  *      <assign>  <- affect our values
 707  *
 708  *      perf_tp_event(event_call->id, __addr, __count, entry,
 709  *                   __entry_size);  <- submit them to perf counter
 710  *
 711  * }
 712  */
 713
 714 #ifdef CONFIG_EVENT_PROFILE
 715
 716 #undef __perf_addr
 717 #define __perf_addr(a) __addr = (a)
 718
 719 #undef __perf_count
 720 #define __perf_count(c) __count = (c)
 721
 722 #undef TRACE_EVENT
 723 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
 724 static void ftrace_profile_##call(proto)                                \
 725 {                                                                       \
 726         struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
 727         extern int perf_swevent_get_recursion_context(void);            \
 728         extern void perf_swevent_put_recursion_context(int rctx);       \
 729         struct ftrace_event_call *event_call = &event_##call;           \
 730         extern void perf_tp_event(int, u64, u64, void *, int);          \
 731         struct ftrace_raw_##call *entry;                                \
 732         u64 __addr = 0, __count = 1;                                    \
 733         unsigned long irq_flags;                                        \
 734         struct trace_entry *ent;                                        \
 735         int __entry_size;                                               \
 736         int __data_size;                                                \
 737         char *trace_buf;                                                \
 738         char *raw_data;                                                 \
 739         int __cpu;                                                      \
 740         int rctx;                                                       \
 741         int pc;                                                         \
 742                                                                         \
 743         pc = preempt_count();                                           \
 744                                                                         \
 745         __data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
 746         __entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
 747                              sizeof(u64));                              \
 748         __entry_size -= sizeof(u32);                                    \
 749                                                                         \
 750         if (WARN_ONCE(__entry_size > FTRACE_MAX_PROFILE_SIZE,           \
 751                       "profile buffer not large enough"))               \
 752                 return;                                                 \
 753                                                                         \
 754         local_irq_save(irq_flags);                                      \
 755                                                                         \
 756         rctx = perf_swevent_get_recursion_context();                    \
 757         if (rctx < 0)                                                   \
 758                 goto end_recursion;                                     \
 759                                                                         \
 760         __cpu = smp_processor_id();                                     \
 761                                                                         \
 762         if (in_nmi())                                                   \
 763                 trace_buf = rcu_dereference(perf_trace_buf_nmi);        \
 764         else                                                            \
 765                 trace_buf = rcu_dereference(perf_trace_buf);            \
 766                                                                         \
 767         if (!trace_buf)                                                 \
 768                 goto end;                                               \
 769                                                                         \
 770         raw_data = per_cpu_ptr(trace_buf, __cpu);                       \
 771                                                                         \
 772         *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL;         \
 773         entry = (struct ftrace_raw_##call *)raw_data;                   \
 774         ent = &entry->ent;                                              \
 775         tracing_generic_entry_update(ent, irq_flags, pc);               \
 776         ent->type = event_call->id;                                     \
 777                                                                         \
 778         tstruct                                                         \
 779                                                                         \
 780         { assign; }                                                     \
 781                                                                         \
 782         perf_tp_event(event_call->id, __addr, __count, entry,           \
 783                              __entry_size);                             \
 784                                                                         \
 785 end:                                                                    \
 786         perf_swevent_put_recursion_context(rctx);                       \
 787 end_recursion:                                                          \
 788         local_irq_restore(irq_flags);                                   \
 789                                                                         \
 790 }
 791
 792 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 793 #endif /* CONFIG_EVENT_PROFILE */
 794
 795 #undef _TRACE_PROFILE_INIT
 796