SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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 __array
  22 #define __array(type, item, len)        type    item[len];
  23
  24 #undef __field
  25 #define __field(type, item)             type    item;
  26
  27 #undef __string
  28 #define __string(item, src)             unsigned short  __str_loc_##item;
  29
  30 #undef TP_STRUCT__entry
  31 #define TP_STRUCT__entry(args...) args
  32
  33 #undef TRACE_EVENT
  34 #define TRACE_EVENT(name, proto, args, tstruct, assign, print)  \
  35         struct ftrace_raw_##name {                              \
  36                 struct trace_entry      ent;                    \
  37                 tstruct                                         \
  38                 char                    __str_data[0];          \
  39         };                                                      \
  40         static struct ftrace_event_call event_##name
  41
  42 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
  43
  44
  45 /*
  46  * Stage 2 of the trace events.
  47  *
  48  * Include the following:
  49  *
  50  * struct ftrace_str_offsets_<call> {
  51  *      int                             <str1>;
  52  *      int                             <str2>;
  53  *      [...]
  54  * };
  55  *
  56  * The __string() macro will create each int <str>, this is to
  57  * keep the offset of each string from the beggining of the event
  58  * once we perform the strlen() of the src strings.
  59  *
  60  */
  61
  62 #undef __array
  63 #define __array(type, item, len)
  64
  65 #undef __field
  66 #define __field(type, item);
  67
  68 #undef __string
  69 #define __string(item, src)     int item;
  70
  71 #undef TRACE_EVENT
  72 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
  73         struct ftrace_str_offsets_##call {                              \
  74                 tstruct;                                                \
  75         };
  76
  77 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
  78
  79 /*
  80  * Stage 3 of the trace events.
  81  *
  82  * Override the macros in <trace/trace_events.h> to include the following:
  83  *
  84  * enum print_line_t
  85  * ftrace_raw_output_<call>(struct trace_iterator *iter, int flags)
  86  * {
  87  *      struct trace_seq *s = &iter->seq;
  88  *      struct ftrace_raw_<call> *field; <-- defined in stage 1
  89  *      struct trace_entry *entry;
  90  *      struct trace_seq *p;
  91  *      int ret;
  92  *
  93  *      entry = iter->ent;
  94  *
  95  *      if (entry->type != event_<call>.id) {
  96  *              WARN_ON_ONCE(1);
  97  *              return TRACE_TYPE_UNHANDLED;
  98  *      }
  99  *
 100  *      field = (typeof(field))entry;
 101  *
 102  *      p = get_cpu_var(ftrace_event_seq);
 103  *      ret = trace_seq_printf(s, <TP_printk> "\n");
 104  *      put_cpu();
 105  *      if (!ret)
 106  *              return TRACE_TYPE_PARTIAL_LINE;
 107  *
 108  *      return TRACE_TYPE_HANDLED;
 109  * }
 110  *
 111  * This is the method used to print the raw event to the trace
 112  * output format. Note, this is not needed if the data is read
 113  * in binary.
 114  */
 115
 116 #undef __entry
 117 #define __entry field
 118
 119 #undef TP_printk
 120 #define TP_printk(fmt, args...) fmt "\n", args
 121
 122 #undef __get_str
 123 #define __get_str(field)        ((char *)__entry + __entry->__str_loc_##field)
 124
 125 #undef __print_flags
 126 #define __print_flags(flag, delim, flag_array...)                       \
 127         ({                                                              \
 128                 static const struct trace_print_flags flags[] =         \
 129                         { flag_array, { -1, NULL }};                    \
 130                 ftrace_print_flags_seq(p, delim, flag, flags);          \
 131         })
 132
 133 #undef __print_symbolic
 134 #define __print_symbolic(value, symbol_array...)                        \
 135         ({                                                              \
 136                 static const struct trace_print_flags symbols[] =       \
 137                         { symbol_array, { -1, NULL }};                  \
 138                 ftrace_print_symbols_seq(p, value, symbols);            \
 139         })
 140
 141 #undef TRACE_EVENT
 142 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
 143 enum print_line_t                                                       \
 144 ftrace_raw_output_##call(struct trace_iterator *iter, int flags)        \
 145 {                                                                       \
 146         struct trace_seq *s = &iter->seq;                               \
 147         struct ftrace_raw_##call *field;                                \
 148         struct trace_entry *entry;                                      \
 149         struct trace_seq *p;                                            \
 150         int ret;                                                        \
 151                                                                         \
 152         entry = iter->ent;                                              \
 153                                                                         \
 154         if (entry->type != event_##call.id) {                           \
 155                 WARN_ON_ONCE(1);                                        \
 156                 return TRACE_TYPE_UNHANDLED;                            \
 157         }                                                               \
 158                                                                         \
 159         field = (typeof(field))entry;                                   \
 160                                                                         \
 161         p = &get_cpu_var(ftrace_event_seq);                             \
 162         ret = trace_seq_printf(s, #call ": " print);                    \
 163         put_cpu();                                                      \
 164         if (!ret)                                                       \
 165                 return TRACE_TYPE_PARTIAL_LINE;                         \
 166                                                                         \
 167         return TRACE_TYPE_HANDLED;                                      \
 168 }
 169
 170 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 171
 172 /*
 173  * Setup the showing format of trace point.
 174  *
 175  * int
 176  * ftrace_format_##call(struct trace_seq *s)
 177  * {
 178  *      struct ftrace_raw_##call field;
 179  *      int ret;
 180  *
 181  *      ret = trace_seq_printf(s, #type " " #item ";"
 182  *                             " offset:%u; size:%u;\n",
 183  *                             offsetof(struct ftrace_raw_##call, item),
 184  *                             sizeof(field.type));
 185  *
 186  * }
 187  */
 188
 189 #undef TP_STRUCT__entry
 190 #define TP_STRUCT__entry(args...) args
 191
 192 #undef __field
 193 #define __field(type, item)                                     \
 194         ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"      \
 195                                "offset:%u;\tsize:%u;\n",                \
 196                                (unsigned int)offsetof(typeof(field), item), \
 197                                (unsigned int)sizeof(field.item));       \
 198         if (!ret)                                                       \
 199                 return 0;
 200
 201 #undef __array
 202 #define __array(type, item, len)                                                \
 203         ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t"    \
 204                                "offset:%u;\tsize:%u;\n",                \
 205                                (unsigned int)offsetof(typeof(field), item), \
 206                                (unsigned int)sizeof(field.item));       \
 207         if (!ret)                                                       \
 208                 return 0;
 209
 210 #undef __string
 211 #define __string(item, src)                                                    \
 212         ret = trace_seq_printf(s, "\tfield: __str_loc " #item ";\t"            \
 213                                "offset:%u;tsize:%u;\n",                        \
 214                                (unsigned int)offsetof(typeof(field),           \
 215                                         __str_loc_##item),                     \
 216                                (unsigned int)sizeof(field.__str_loc_##item));  \
 217         if (!ret)                                                              \
 218                 return 0;
 219
 220 #undef __entry
 221 #define __entry REC
 222
 223 #undef TP_printk
 224 #define TP_printk(fmt, args...) "%s, %s\n", #fmt, __stringify(args)
 225
 226 #undef TP_fast_assign
 227 #define TP_fast_assign(args...) args
 228
 229 #undef TRACE_EVENT
 230 #define TRACE_EVENT(call, proto, args, tstruct, func, print)            \
 231 static int                                                              \
 232 ftrace_format_##call(struct trace_seq *s)                               \
 233 {                                                                       \
 234         struct ftrace_raw_##call field __attribute__((unused));         \
 235         int ret = 0;                                                    \
 236                                                                         \
 237         tstruct;                                                        \
 238                                                                         \
 239         trace_seq_printf(s, "\nprint fmt: " print);                     \
 240                                                                         \
 241         return ret;                                                     \
 242 }
 243
 244 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 245
 246 #undef __field
 247 #define __field(type, item)                                             \
 248         ret = trace_define_field(event_call, #type, #item,              \
 249                                  offsetof(typeof(field), item),         \
 250                                  sizeof(field.item), is_signed_type(type));     \
 251         if (ret)                                                        \
 252                 return ret;
 253
 254 #undef __array
 255 #define __array(type, item, len)                                        \
 256         BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);                         \
 257         ret = trace_define_field(event_call, #type "[" #len "]", #item, \
 258                                  offsetof(typeof(field), item),         \
 259                                  sizeof(field.item), 0);                \
 260         if (ret)                                                        \
 261                 return ret;
 262
 263 #undef __string
 264 #define __string(item, src)                                                    \
 265         ret = trace_define_field(event_call, "__str_loc", #item,               \
 266                                 offsetof(typeof(field), __str_loc_##item),     \
 267                                  sizeof(field.__str_loc_##item), 0);
 268
 269 #undef TRACE_EVENT
 270 #define TRACE_EVENT(call, proto, args, tstruct, func, print)            \
 271 int                                                                     \
 272 ftrace_define_fields_##call(void)                                       \
 273 {                                                                       \
 274         struct ftrace_raw_##call field;                                 \
 275         struct ftrace_event_call *event_call = &event_##call;           \
 276         int ret;                                                        \
 277                                                                         \
 278         __common_field(int, type, 1);                                   \
 279         __common_field(unsigned char, flags, 0);                        \
 280         __common_field(unsigned char, preempt_count, 0);                \
 281         __common_field(int, pid, 1);                                    \
 282         __common_field(int, tgid, 1);                                   \
 283                                                                         \
 284         tstruct;                                                        \
 285                                                                         \
 286         return ret;                                                     \
 287 }
 288
 289 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 290
 291 /*
 292  * Stage 4 of the trace events.
 293  *
 294  * Override the macros in <trace/trace_events.h> to include the following:
 295  *
 296  * static void ftrace_event_<call>(proto)
 297  * {
 298  *      event_trace_printk(_RET_IP_, "<call>: " <fmt>);
 299  * }
 300  *
 301  * static int ftrace_reg_event_<call>(void)
 302  * {
 303  *      int ret;
 304  *
 305  *      ret = register_trace_<call>(ftrace_event_<call>);
 306  *      if (!ret)
 307  *              pr_info("event trace: Could not activate trace point "
 308  *                      "probe to  <call>");
 309  *      return ret;
 310  * }
 311  *
 312  * static void ftrace_unreg_event_<call>(void)
 313  * {
 314  *      unregister_trace_<call>(ftrace_event_<call>);
 315  * }
 316  *
 317  *
 318  * For those macros defined with TRACE_EVENT:
 319  *
 320  * static struct ftrace_event_call event_<call>;
 321  *
 322  * static void ftrace_raw_event_<call>(proto)
 323  * {
 324  *      struct ring_buffer_event *event;
 325  *      struct ftrace_raw_<call> *entry; <-- defined in stage 1
 326  *      unsigned long irq_flags;
 327  *      int pc;
 328  *
 329  *      local_save_flags(irq_flags);
 330  *      pc = preempt_count();
 331  *
 332  *      event = trace_current_buffer_lock_reserve(event_<call>.id,
 333  *                                sizeof(struct ftrace_raw_<call>),
 334  *                                irq_flags, pc);
 335  *      if (!event)
 336  *              return;
 337  *      entry   = ring_buffer_event_data(event);
 338  *
 339  *      <assign>;  <-- Here we assign the entries by the __field and
 340  *                      __array macros.
 341  *
 342  *      trace_current_buffer_unlock_commit(event, irq_flags, pc);
 343  * }
 344  *
 345  * static int ftrace_raw_reg_event_<call>(void)
 346  * {
 347  *      int ret;
 348  *
 349  *      ret = register_trace_<call>(ftrace_raw_event_<call>);
 350  *      if (!ret)
 351  *              pr_info("event trace: Could not activate trace point "
 352  *                      "probe to <call>");
 353  *      return ret;
 354  * }
 355  *
 356  * static void ftrace_unreg_event_<call>(void)
 357  * {
 358  *      unregister_trace_<call>(ftrace_raw_event_<call>);
 359  * }
 360  *
 361  * static struct trace_event ftrace_event_type_<call> = {
 362  *      .trace                  = ftrace_raw_output_<call>, <-- stage 2
 363  * };
 364  *
 365  * static int ftrace_raw_init_event_<call>(void)
 366  * {
 367  *      int id;
 368  *
 369  *      id = register_ftrace_event(&ftrace_event_type_<call>);
 370  *      if (!id)
 371  *              return -ENODEV;
 372  *      event_<call>.id = id;
 373  *      return 0;
 374  * }
 375  *
 376  * static struct ftrace_event_call __used
 377  * __attribute__((__aligned__(4)))
 378  * __attribute__((section("_ftrace_events"))) event_<call> = {
 379  *      .name                   = "<call>",
 380  *      .system                 = "<system>",
 381  *      .raw_init               = ftrace_raw_init_event_<call>,
 382  *      .regfunc                = ftrace_reg_event_<call>,
 383  *      .unregfunc              = ftrace_unreg_event_<call>,
 384  *      .show_format            = ftrace_format_<call>,
 385  * }
 386  *
 387  */
 388
 389 #undef TP_FMT
 390 #define TP_FMT(fmt, args...)    fmt "\n", ##args
 391
 392 #ifdef CONFIG_EVENT_PROFILE
 393 #define _TRACE_PROFILE(call, proto, args)                               \
 394 static void ftrace_profile_##call(proto)                                \
 395 {                                                                       \
 396         extern void perf_tpcounter_event(int);                          \
 397         perf_tpcounter_event(event_##call.id);                          \
 398 }                                                                       \
 399                                                                         \
 400 static int ftrace_profile_enable_##call(struct ftrace_event_call *event_call) \
 401 {                                                                       \
 402         int ret = 0;                                                    \
 403                                                                         \
 404         if (!atomic_inc_return(&event_call->profile_count))             \
 405                 ret = register_trace_##call(ftrace_profile_##call);     \
 406                                                                         \
 407         return ret;                                                     \
 408 }                                                                       \
 409                                                                         \
 410 static void ftrace_profile_disable_##call(struct ftrace_event_call *event_call)\
 411 {                                                                       \
 412         if (atomic_add_negative(-1, &event_call->profile_count))        \
 413                 unregister_trace_##call(ftrace_profile_##call);         \
 414 }
 415
 416 #define _TRACE_PROFILE_INIT(call)                                       \
 417         .profile_count = ATOMIC_INIT(-1),                               \
 418         .profile_enable = ftrace_profile_enable_##call,                 \
 419         .profile_disable = ftrace_profile_disable_##call,
 420
 421 #else
 422 #define _TRACE_PROFILE(call, proto, args)
 423 #define _TRACE_PROFILE_INIT(call)
 424 #endif
 425
 426 #undef __entry
 427 #define __entry entry
 428
 429 #undef __field
 430 #define __field(type, item)
 431
 432 #undef __array
 433 #define __array(type, item, len)
 434
 435 #undef __string
 436 #define __string(item, src)                                             \
 437         __str_offsets.item = __str_size +                               \
 438                              offsetof(typeof(*entry), __str_data);      \
 439         __str_size += strlen(src) + 1;
 440
 441 #undef __assign_str
 442 #define __assign_str(dst, src)                                          \
 443         __entry->__str_loc_##dst = __str_offsets.dst;                   \
 444         strcpy(__get_str(dst), src);
 445
 446 #undef TRACE_EVENT
 447 #define TRACE_EVENT(call, proto, args, tstruct, assign, print)          \
 448 _TRACE_PROFILE(call, PARAMS(proto), PARAMS(args))                       \
 449                                                                         \
 450 static struct ftrace_event_call event_##call;                           \
 451                                                                         \
 452 static void ftrace_raw_event_##call(proto)                              \
 453 {                                                                       \
 454         struct ftrace_str_offsets_##call __maybe_unused __str_offsets;  \
 455         struct ftrace_event_call *event_call = &event_##call;           \
 456         struct ring_buffer_event *event;                                \
 457         struct ftrace_raw_##call *entry;                                \
 458         unsigned long irq_flags;                                        \
 459         int __str_size = 0;                                             \
 460         int pc;                                                         \
 461                                                                         \
 462         local_save_flags(irq_flags);                                    \
 463         pc = preempt_count();                                           \
 464                                                                         \
 465         tstruct;                                                        \
 466                                                                         \
 467         event = trace_current_buffer_lock_reserve(event_##call.id,      \
 468                                  sizeof(struct ftrace_raw_##call) + __str_size,\
 469                                  irq_flags, pc);                        \
 470         if (!event)                                                     \
 471                 return;                                                 \
 472         entry   = ring_buffer_event_data(event);                        \
 473                                                                         \
 474         assign;                                                         \
 475                                                                         \
 476         if (!filter_current_check_discard(event_call, entry, event))    \
 477                 trace_nowake_buffer_unlock_commit(event, irq_flags, pc); \
 478 }                                                                       \
 479                                                                         \
 480 static int ftrace_raw_reg_event_##call(void)                            \
 481 {                                                                       \
 482         int ret;                                                        \
 483                                                                         \
 484         ret = register_trace_##call(ftrace_raw_event_##call);           \
 485         if (ret)                                                        \
 486                 pr_info("event trace: Could not activate trace point "  \
 487                         "probe to " #call "\n");                        \
 488         return ret;                                                     \
 489 }                                                                       \
 490                                                                         \
 491 static void ftrace_raw_unreg_event_##call(void)                         \
 492 {                                                                       \
 493         unregister_trace_##call(ftrace_raw_event_##call);               \
 494 }                                                                       \
 495                                                                         \
 496 static struct trace_event ftrace_event_type_##call = {                  \
 497         .trace                  = ftrace_raw_output_##call,             \
 498 };                                                                      \
 499                                                                         \
 500 static int ftrace_raw_init_event_##call(void)                           \
 501 {                                                                       \
 502         int id;                                                         \
 503                                                                         \
 504         id = register_ftrace_event(&ftrace_event_type_##call);          \
 505         if (!id)                                                        \
 506                 return -ENODEV;                                         \
 507         event_##call.id = id;                                           \
 508         INIT_LIST_HEAD(&event_##call.fields);                           \
 509         init_preds(&event_##call);                                      \
 510         return 0;                                                       \
 511 }                                                                       \
 512                                                                         \
 513 static struct ftrace_event_call __used                                  \
 514 __attribute__((__aligned__(4)))                                         \
 515 __attribute__((section("_ftrace_events"))) event_##call = {             \
 516         .name                   = #call,                                \
 517         .system                 = __stringify(TRACE_SYSTEM),            \
 518         .event                  = &ftrace_event_type_##call,            \
 519         .raw_init               = ftrace_raw_init_event_##call,         \
 520         .regfunc                = ftrace_raw_reg_event_##call,          \
 521         .unregfunc              = ftrace_raw_unreg_event_##call,        \
 522         .show_format            = ftrace_format_##call,                 \
 523         .define_fields          = ftrace_define_fields_##call,          \
 524         _TRACE_PROFILE_INIT(call)                                       \
 525 }
 526
 527 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
 528
 529 #undef _TRACE_PROFILE
 530 #undef _TRACE_PROFILE_INIT
 531