include/ust/lttng-tracepoint-event.h

   1 /*
   2  * Copyright (C) 2009     Steven Rostedt <srostedt@redhat.com>
   3  * Copyright (C) 2011     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation;
   8  * version 2.1 of the License.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  18  */
  19
  20 #include <stdio.h>
  21 #include <urcu/compiler.h>
  22 #include <ust/lttng-events.h>
  23 #include <ust/usterr-signal-safe.h>
  24 #include <ust/ringbuffer-config.h>
  25
  26 /*
  27  * Macro declarations used for all stages.
  28  */
  29
  30 #undef ctf_integer
  31 #define ctf_integer(_type, _item, _src)                         \
  32         ctf_integer_ext(_type, _item, _src, BYTE_ORDER, 10)
  33
  34 #undef ctf_integer_hex
  35 #define ctf_integer_hex(_type, _item, _src)                     \
  36         ctf_integer_ext(_type, _item, _src, BYTE_ORDER, 16)
  37
  38 #undef ctf_integer_network
  39 #define ctf_integer_network(_type, _item, _src)                 \
  40         ctf_integer_ext(_type, _item, _src, BIG_ENDIAN, 10)
  41
  42 #undef ctf_integer_network_hex
  43 #define ctf_integer_network_hex(_type, _item, _src)             \
  44         ctf_integer_ext(_type, _item, _src, BIG_ENDIAN, 16)
  45
  46 /* ctf_float is redefined at each step */
  47
  48 #undef ctf_array
  49 #define ctf_array(_type, _item, _src, _length)                  \
  50         ctf_array_encoded(_type, _item, _src, _length, none)
  51
  52 #undef ctf_array_text
  53 #define ctf_array_text(_type, _item, _src, _length)             \
  54         ctf_array_encoded(_type, _item, _src, _length, UTF8)
  55
  56 #undef ctf_sequence
  57 #define ctf_sequence(_type, _item, _src, _length_type, _src_length)     \
  58         ctf_sequence_encoded(_type, _item, _src,                        \
  59                         _length_type, _src_length, none)
  60
  61 #undef ctf_sequence_text
  62 #define ctf_sequence_text(_type, _item, _src, _length_type, _src_length) \
  63         ctf_sequence_encoded(_type, _item, _src,                         \
  64                         _length_type, _src_length, UTF8)
  65
  66 /* ctf_string is redefined at each step */
  67
  68 /*
  69  * TRACEPOINT_EVENT_CLASS can be used to add a generic function handlers
  70  * for events. That is, if all events have the same parameters and just
  71  * have distinct trace points.  Each tracepoint can be defined with
  72  * TRACEPOINT_EVENT_INSTANCE and that will map the
  73  * TRACEPOINT_EVENT_CLASS to the tracepoint.
  74  *
  75  * TRACEPOINT_EVENT is a one to one mapping between tracepoint and
  76  * template.
  77  */
  78
  79 #undef TRACEPOINT_EVENT
  80 #define TRACEPOINT_EVENT(name, proto, args, fields)     \
  81         TRACEPOINT_EVENT_CLASS(name,                    \
  82                              TP_PARAMS(proto),          \
  83                              TP_PARAMS(args),           \
  84                              TP_PARAMS(fields))         \
  85         TRACEPOINT_EVENT_INSTANCE(name, name, TP_PARAMS(proto), TP_PARAMS(args))
  86
  87 #undef TRACEPOINT_EVENT_NOARGS
  88 #define TRACEPOINT_EVENT_NOARGS(name, fields)           \
  89         TRACEPOINT_EVENT_CLASS_NOARGS(name,             \
  90                              TP_PARAMS(fields))         \
  91         TRACEPOINT_EVENT_INSTANCE_NOARGS(name, name)
  92
  93 /* Helpers */
  94 #define _TP_ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
  95
  96 #define _tp_max_t(type, x, y)                           \
  97         ({                                              \
  98                 type __max1 = (x);                      \
  99                 type __max2 = (y);                      \
 100                 __max1 > __max2 ? __max1: __max2;       \
 101         })
 102
 103
 104 /*
 105  * Stage 1 of the trace events.
 106  *
 107  * Create event field type metadata section.
 108  * Each event produce an array of fields.
 109  */
 110
 111 /* Reset all macros within TRACEPOINT_EVENT */
 112 #include <ust/lttng-tracepoint-event-reset.h>
 113
 114 /* Named field types must be defined in lttng-types.h */
 115
 116 #undef ctf_integer_ext
 117 #define ctf_integer_ext(_type, _item, _src, _byte_order, _base) \
 118         {                                                       \
 119           .name = #_item,                                       \
 120           .type = __type_integer(_type, _byte_order, _base, none),\
 121         },
 122
 123 #undef ctf_float
 124 #define ctf_float(_type, _item, _src)                           \
 125         {                                                       \
 126           .name = #_item,                                       \
 127           .type = __type_float(_type),                          \
 128         },
 129
 130 #undef ctf_array_encoded
 131 #define ctf_array_encoded(_type, _item, _src, _length, _encoding) \
 132         {                                                       \
 133           .name = #_item,                                       \
 134           .type =                                               \
 135                 {                                               \
 136                   .atype = atype_array,                         \
 137                   .u.array =                                    \
 138                         {                                       \
 139                             .length = _length,                  \
 140                             .elem_type = __type_integer(_type, BYTE_ORDER, 10, _encoding), \
 141                         },                                      \
 142                 },                                              \
 143         },
 144
 145 #undef ctf_sequence_encoded
 146 #define ctf_sequence_encoded(_type, _item, _src,        \
 147                         _length_type, _src_length, _encoding)   \
 148         {                                                       \
 149           .name = #_item,                                       \
 150           .type =                                               \
 151                 {                                               \
 152                   .atype = atype_sequence,                      \
 153                   .u.sequence =                                 \
 154                         {                                       \
 155                             .length_type = __type_integer(_length_type, BYTE_ORDER, 10, none), \
 156                             .elem_type = __type_integer(_type, BYTE_ORDER, 10, _encoding), \
 157                         },                                      \
 158                 },                                              \
 159         },
 160
 161 #undef ctf_string
 162 #define ctf_string(_item, _src)                                 \
 163         {                                                       \
 164           .name = #_item,                                       \
 165           .type =                                               \
 166                 {                                               \
 167                   .atype = atype_string,                        \
 168                   .u.basic.string.encoding = lttng_encode_UTF8, \
 169                 },                                              \
 170         },
 171
 172 #undef TP_FIELDS
 173 #define TP_FIELDS(args...) args /* Only one used in this phase */
 174
 175 #undef TRACEPOINT_EVENT_CLASS_NOARGS
 176 #define TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields)                        \
 177         static const struct lttng_event_field __event_fields___##_name[] = { \
 178                 _fields                                                      \
 179         };
 180
 181 #undef TRACEPOINT_EVENT_CLASS
 182 #define TRACEPOINT_EVENT_CLASS(_name, _proto, _args, _fields)                \
 183         TRACEPOINT_EVENT_CLASS_NOARGS(_name, TP_PARAMS(_fields))
 184
 185 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 186
 187 /*
 188  * Stage 2 of the trace events.
 189  *
 190  * Create probe callback prototypes.
 191  */
 192
 193 /* Reset all macros within TRACEPOINT_EVENT */
 194 #include <ust/lttng-tracepoint-event-reset.h>
 195
 196 #undef TP_PROTO
 197 #define TP_PROTO(args...) args
 198
 199 #undef TRACEPOINT_EVENT_CLASS
 200 #define TRACEPOINT_EVENT_CLASS(_name, _proto, _args, _fields)                \
 201 static void __event_probe__##_name(void *__data, _proto);
 202
 203 #undef TRACEPOINT_EVENT_CLASS_NOARGS
 204 #define TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields)                        \
 205 static void __event_probe__##_name(void *__data);
 206
 207 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 208
 209 /*
 210  * Stage 3 of the trace events.
 211  *
 212  * Create an array of events.
 213  */
 214
 215 /* Named field types must be defined in lttng-types.h */
 216
 217 /* Reset all macros within TRACEPOINT_EVENT */
 218 #include <ust/lttng-tracepoint-event-reset.h>
 219
 220 #undef TRACEPOINT_EVENT_INSTANCE_NOARGS
 221 #define TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name)                     \
 222                 {                                                              \
 223                         .fields = __event_fields___##_template,                \
 224                         .name = #_name,                                        \
 225                         .probe_callback = (void *) &__event_probe__##_template,\
 226                         .nr_fields = _TP_ARRAY_SIZE(__event_fields___##_template), \
 227                 },
 228
 229 #undef TRACEPOINT_EVENT_INSTANCE
 230 #define TRACEPOINT_EVENT_INSTANCE(_template, _name, _proto, _args)             \
 231         TRACEPOINT_EVENT_INSTANCE_NOARGS(_template, _name)
 232
 233 #define TP_ID1(_token, _system) _token##_system
 234 #define TP_ID(_token, _system)  TP_ID1(_token, _system)
 235
 236 static const struct lttng_event_desc TP_ID(__event_desc___, TRACEPOINT_SYSTEM)[] = {
 237 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 238 };
 239
 240 #undef TP_ID1
 241 #undef TP_ID
 242
 243
 244 /*
 245  * Stage 4 of the trace events.
 246  *
 247  * Create a toplevel descriptor for the whole probe.
 248  */
 249
 250 #define TP_ID1(_token, _system) _token##_system
 251 #define TP_ID(_token, _system)  TP_ID1(_token, _system)
 252
 253 /* non-const because list head will be modified when registered. */
 254 static struct lttng_probe_desc TP_ID(__probe_desc___, TRACEPOINT_SYSTEM) = {
 255         .event_desc = TP_ID(__event_desc___, TRACEPOINT_SYSTEM),
 256         .nr_events = _TP_ARRAY_SIZE(TP_ID(__event_desc___, TRACEPOINT_SYSTEM)),
 257 };
 258
 259 #undef TP_ID1
 260 #undef TP_ID
 261
 262 /*
 263  * Stage 5 of the trace events.
 264  *
 265  * Create static inline function that calculates event size.
 266  */
 267
 268 /* Reset all macros within TRACEPOINT_EVENT */
 269 #include <ust/lttng-tracepoint-event-reset.h>
 270
 271 /* Named field types must be defined in lttng-types.h */
 272
 273 #undef ctf_integer_ext
 274 #define ctf_integer_ext(_type, _item, _src, _byte_order, _base)                \
 275         __event_len += lib_ring_buffer_align(__event_len, lttng_alignof(_type)); \
 276         __event_len += sizeof(_type);
 277
 278 #undef ctf_float
 279 #define ctf_float(_type, _item, _src)                                          \
 280         __event_len += lib_ring_buffer_align(__event_len, lttng_alignof(_type)); \
 281         __event_len += sizeof(_type);
 282
 283 #undef ctf_array_encoded
 284 #define ctf_array_encoded(_type, _item, _src, _length, _encoding)              \
 285         __event_len += lib_ring_buffer_align(__event_len, lttng_alignof(_type)); \
 286         __event_len += sizeof(_type) * (_length);
 287
 288 #undef ctf_sequence_encoded
 289 #define ctf_sequence_encoded(_type, _item, _src, _length_type,  \
 290                         _src_length, _encoding)                 \
 291         __event_len += lib_ring_buffer_align(__event_len, lttng_alignof(_length_type));   \
 292         __event_len += sizeof(_length_type);                                   \
 293         __event_len += lib_ring_buffer_align(__event_len, lttng_alignof(_type)); \
 294         __dynamic_len[__dynamic_len_idx] = (_src_length);                      \
 295         __event_len += sizeof(_type) * __dynamic_len[__dynamic_len_idx];       \
 296         __dynamic_len_idx++;
 297
 298 #undef ctf_string
 299 #define ctf_string(_item, _src)                                                \
 300         __event_len += __dynamic_len[__dynamic_len_idx++] = strlen(_src) + 1;
 301
 302 #undef TP_PROTO
 303 #define TP_PROTO(args...) args
 304
 305 #undef TP_FIELDS
 306 #define TP_FIELDS(args...) args
 307
 308 #undef TRACEPOINT_EVENT_CLASS
 309 #define TRACEPOINT_EVENT_CLASS(_name, _proto, _args, _fields)                 \
 310 static inline size_t __event_get_size__##_name(size_t *__dynamic_len, _proto) \
 311 {                                                                             \
 312         size_t __event_len = 0;                                               \
 313         unsigned int __dynamic_len_idx = 0;                                   \
 314                                                                               \
 315         if (0)                                                                \
 316                 (void) __dynamic_len_idx;       /* don't warn if unused */    \
 317         _fields                                                               \
 318         return __event_len;                                                   \
 319 }
 320
 321 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 322
 323 /*
 324  * Stage 6 of the trace events.
 325  *
 326  * Create static inline function that calculates event payload alignment.
 327  */
 328
 329 /* Reset all macros within TRACEPOINT_EVENT */
 330 #include <ust/lttng-tracepoint-event-reset.h>
 331
 332 /* Named field types must be defined in lttng-types.h */
 333
 334 #undef ctf_integer_ext
 335 #define ctf_integer_ext(_type, _item, _src, _byte_order, _base)                \
 336         __event_align = _tp_max_t(size_t, __event_align, lttng_alignof(_type));
 337
 338 #undef ctf_float
 339 #define ctf_float(_type, _item, _src)                                          \
 340         __event_align = _tp_max_t(size_t, __event_align, lttng_alignof(_type));
 341
 342 #undef ctf_array_encoded
 343 #define ctf_array_encoded(_type, _item, _src, _length, _encoding)              \
 344         __event_align = _tp_max_t(size_t, __event_align, lttng_alignof(_type));
 345
 346 #undef ctf_sequence_encoded
 347 #define ctf_sequence_encoded(_type, _item, _src, _length_type,  \
 348                         _src_length, _encoding)                 \
 349         __event_align = _tp_max_t(size_t, __event_align, lttng_alignof(_length_type));    \
 350         __event_align = _tp_max_t(size_t, __event_align, lttng_alignof(_type));
 351
 352 #undef ctf_string
 353 #define ctf_string(_item, _src)
 354
 355 #undef TP_PROTO
 356 #define TP_PROTO(args...) args
 357
 358 #undef TP_FIELDS
 359 #define TP_FIELDS(args...) args
 360
 361 #undef TRACEPOINT_EVENT_CLASS
 362 #define TRACEPOINT_EVENT_CLASS(_name, _proto, _args, _fields)                 \
 363 static inline size_t __event_get_align__##_name(_proto)                       \
 364 {                                                                             \
 365         size_t __event_align = 1;                                             \
 366         _fields                                                               \
 367         return __event_align;                                                 \
 368 }
 369
 370 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 371
 372
 373 /*
 374  * Stage 7 of the trace events.
 375  *
 376  * Create the probe function : call even size calculation and write event data
 377  * into the buffer.
 378  *
 379  * We use both the field and assignment macros to write the fields in the order
 380  * defined in the field declaration. The field declarations control the
 381  * execution order, jumping to the appropriate assignment block.
 382  */
 383
 384 /* Reset all macros within TRACEPOINT_EVENT */
 385 #include <ust/lttng-tracepoint-event-reset.h>
 386
 387 #undef ctf_integer_ext
 388 #define ctf_integer_ext(_type, _item, _src, _byte_order, _base)         \
 389         {                                                               \
 390                 _type __tmp = (_src);                                   \
 391                 lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(__tmp));\
 392                 __chan->ops->event_write(&__ctx, &__tmp, sizeof(__tmp));\
 393         }
 394
 395 #undef ctf_float
 396 #define ctf_float(_type, _item, _src)                                   \
 397         {                                                               \
 398                 _type __tmp = (_src);                                   \
 399                 lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(__tmp));\
 400                 __chan->ops->event_write(&__ctx, &__tmp, sizeof(__tmp));\
 401         }
 402
 403 #undef ctf_array_encoded
 404 #define ctf_array_encoded(_type, _item, _src, _length, _encoding)       \
 405         lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(_type));        \
 406         __chan->ops->event_write(&__ctx, _src, sizeof(_type) * (_length));
 407
 408 #undef ctf_sequence_encoded
 409 #define ctf_sequence_encoded(_type, _item, _src, _length_type,          \
 410                         _src_length, _encoding)                 \
 411         {                                                               \
 412                 _length_type __tmpl = __dynamic_len[__dynamic_len_idx]; \
 413                 lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(_length_type));\
 414                 __chan->ops->event_write(&__ctx, &__tmpl, sizeof(_length_type));\
 415         }                                                               \
 416         lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(_type));        \
 417         __chan->ops->event_write(&__ctx, _src,                          \
 418                 sizeof(_type) * __get_dynamic_len(dest));
 419
 420 #undef ctf_string
 421 #define ctf_string(_item, _src)                                         \
 422         lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(*(_src)));      \
 423         __chan->ops->event_write(&__ctx, _src, __get_dynamic_len(dest));
 424
 425 /* Beware: this get len actually consumes the len value */
 426 #undef __get_dynamic_len
 427 #define __get_dynamic_len(field)        __dynamic_len[__dynamic_len_idx++]
 428
 429 #undef TP_PROTO
 430 #define TP_PROTO(args...) args
 431
 432 #undef TP_ARGS
 433 #define TP_ARGS(args...) args
 434
 435 #undef TP_FIELDS
 436 #define TP_FIELDS(args...) args
 437
 438 #undef TRACEPOINT_EVENT_CLASS
 439 #define TRACEPOINT_EVENT_CLASS(_name, _proto, _args, _fields)                 \
 440 static void __event_probe__##_name(void *__data, _proto)                      \
 441 {                                                                             \
 442         struct ltt_event *__event = __data;                                   \
 443         struct ltt_channel *__chan = __event->chan;                           \
 444         struct lttng_ust_lib_ring_buffer_ctx __ctx;                                   \
 445         size_t __event_len, __event_align;                                    \
 446         size_t __dynamic_len_idx = 0;                                         \
 447         size_t __dynamic_len[_TP_ARRAY_SIZE(__event_fields___##_name)];       \
 448         int __ret;                                                            \
 449                                                                               \
 450         if (0)                                                                \
 451                 (void) __dynamic_len_idx;       /* don't warn if unused */    \
 452         if (unlikely(!CMM_ACCESS_ONCE(__chan->session->active)))              \
 453                 return;                                                       \
 454         if (unlikely(!CMM_ACCESS_ONCE(__chan->enabled)))                      \
 455                 return;                                                       \
 456         if (unlikely(!CMM_ACCESS_ONCE(__event->enabled)))                     \
 457                 return;                                                       \
 458         __event_len = __event_get_size__##_name(__dynamic_len, _args);        \
 459         __event_align = __event_get_align__##_name(_args);                    \
 460         lib_ring_buffer_ctx_init(&__ctx, __chan->chan, __event, __event_len,  \
 461                                  __event_align, -1, __chan->handle);          \
 462         __ret = __chan->ops->event_reserve(&__ctx, __event->id);              \
 463         if (__ret < 0)                                                        \
 464                 return;                                                       \
 465         _fields                                                               \
 466         __chan->ops->event_commit(&__ctx);                                    \
 467 }
 468
 469 #undef TRACEPOINT_EVENT_CLASS_NOARGS
 470 #define TRACEPOINT_EVENT_CLASS_NOARGS(_name, _fields)                         \
 471 static void __event_probe__##_name(void *__data)                              \
 472 {                                                                             \
 473         struct ltt_event *__event = __data;                                   \
 474         struct ltt_channel *__chan = __event->chan;                           \
 475         struct lttng_ust_lib_ring_buffer_ctx __ctx;                                   \
 476         size_t __event_len, __event_align;                                    \
 477         int __ret;                                                            \
 478                                                                               \
 479         if (unlikely(!CMM_ACCESS_ONCE(__chan->session->active)))              \
 480                 return;                                                       \
 481         if (unlikely(!CMM_ACCESS_ONCE(__chan->enabled)))                      \
 482                 return;                                                       \
 483         if (unlikely(!CMM_ACCESS_ONCE(__event->enabled)))                     \
 484                 return;                                                       \
 485         __event_len = 0;                                                      \
 486         __event_align = 1;                                                    \
 487         lib_ring_buffer_ctx_init(&__ctx, __chan->chan, __event, __event_len,  \
 488                                  __event_align, -1, __chan->handle);          \
 489         __ret = __chan->ops->event_reserve(&__ctx, __event->id);              \
 490         if (__ret < 0)                                                        \
 491                 return;                                                       \
 492         _fields                                                               \
 493         __chan->ops->event_commit(&__ctx);                                    \
 494 }
 495
 496 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 497
 498 #undef __get_dynamic_len
 499
 500 /*
 501  * Stage 8 of the trace events.
 502  *
 503  * Register/unregister probes at module load/unload.
 504  */
 505
 506 /* Reset all macros within TRACEPOINT_EVENT */
 507 #include <ust/lttng-tracepoint-event-reset.h>
 508
 509 #define TP_ID1(_token, _system) _token##_system
 510 #define TP_ID(_token, _system)  TP_ID1(_token, _system)
 511
 512 static void __attribute__((constructor))
 513 TP_ID(__lttng_events_init__, TRACEPOINT_SYSTEM)(void)
 514 {
 515         int ret;
 516
 517         ret = ltt_probe_register(&TP_ID(__probe_desc___, TRACEPOINT_SYSTEM));
 518         assert(!ret);
 519 }
 520
 521 static void __attribute__((destructor))
 522 TP_ID(__lttng_events_exit__, TRACEPOINT_SYSTEM)(void)
 523 {
 524         ltt_probe_unregister(&TP_ID(__probe_desc___, TRACEPOINT_SYSTEM));
 525 }
 526
 527 #undef TP_ID1
 528 #undef TP_ID