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