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