include/lttng/ust-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 <lttng/ust-events.h>
  23 #include <lttng/usterr-signal-safe.h>
  24 #include <lttng/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(provider, name, proto, args, fields)   \
  81         TRACEPOINT_EVENT_CLASS(provider, name,          \
  82                              TP_PARAMS(proto),          \
  83                              TP_PARAMS(args),           \
  84                              TP_PARAMS(fields))         \
  85         TRACEPOINT_EVENT_INSTANCE(provider, name, name, TP_PARAMS(proto), TP_PARAMS(args))
  86
  87 #undef TRACEPOINT_EVENT_NOARGS
  88 #define TRACEPOINT_EVENT_NOARGS(provider, name, fields) \
  89         TRACEPOINT_EVENT_CLASS_NOARGS(provider, name,   \
  90                              TP_PARAMS(fields))         \
  91         TRACEPOINT_EVENT_INSTANCE_NOARGS(provider, 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 <lttng/ust-tracepoint-event-reset.h>
 113
 114 #undef ctf_integer_ext
 115 #define ctf_integer_ext(_type, _item, _src, _byte_order, _base) \
 116         {                                                       \
 117           .name = #_item,                                       \
 118           .type = __type_integer(_type, _byte_order, _base, none),\
 119         },
 120
 121 #undef ctf_float
 122 #define ctf_float(_type, _item, _src)                           \
 123         {                                                       \
 124           .name = #_item,                                       \
 125           .type = __type_float(_type),                          \
 126         },
 127
 128 #undef ctf_array_encoded
 129 #define ctf_array_encoded(_type, _item, _src, _length, _encoding) \
 130         {                                                       \
 131           .name = #_item,                                       \
 132           .type =                                               \
 133                 {                                               \
 134                   .atype = atype_array,                         \
 135                   .u.array =                                    \
 136                         {                                       \
 137                             .length = _length,                  \
 138                             .elem_type = __type_integer(_type, BYTE_ORDER, 10, _encoding), \
 139                         },                                      \
 140                 },                                              \
 141         },
 142
 143 #undef ctf_sequence_encoded
 144 #define ctf_sequence_encoded(_type, _item, _src,        \
 145                         _length_type, _src_length, _encoding)   \
 146         {                                                       \
 147           .name = #_item,                                       \
 148           .type =                                               \
 149                 {                                               \
 150                   .atype = atype_sequence,                      \
 151                   .u.sequence =                                 \
 152                         {                                       \
 153                             .length_type = __type_integer(_length_type, BYTE_ORDER, 10, none), \
 154                             .elem_type = __type_integer(_type, BYTE_ORDER, 10, _encoding), \
 155                         },                                      \
 156                 },                                              \
 157         },
 158
 159 #undef ctf_string
 160 #define ctf_string(_item, _src)                                 \
 161         {                                                       \
 162           .name = #_item,                                       \
 163           .type =                                               \
 164                 {                                               \
 165                   .atype = atype_string,                        \
 166                   .u.basic.string.encoding = lttng_encode_UTF8, \
 167                 },                                              \
 168         },
 169
 170 #undef TP_FIELDS
 171 #define TP_FIELDS(args...) args /* Only one used in this phase */
 172
 173 #undef TRACEPOINT_EVENT_CLASS_NOARGS
 174 #define TRACEPOINT_EVENT_CLASS_NOARGS(_provider, _name, _fields)                             \
 175         static const struct lttng_event_field __event_fields___##_provider##___##_name[] = { \
 176                 _fields                                                      \
 177         };
 178
 179 #undef TRACEPOINT_EVENT_CLASS
 180 #define TRACEPOINT_EVENT_CLASS(_provider, _name, _proto, _args, _fields)                     \
 181         TRACEPOINT_EVENT_CLASS_NOARGS(_provider, _name, TP_PARAMS(_fields))
 182
 183 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 184
 185 /*
 186  * Stage 2 of the trace events.
 187  *
 188  * Create probe callback prototypes.
 189  */
 190
 191 /* Reset all macros within TRACEPOINT_EVENT */
 192 #include <lttng/ust-tracepoint-event-reset.h>
 193
 194 #undef TP_PROTO
 195 #define TP_PROTO(args...) args
 196
 197 #undef TRACEPOINT_EVENT_CLASS
 198 #define TRACEPOINT_EVENT_CLASS(_provider, _name, _proto, _args, _fields)                     \
 199 static void __event_probe__##_provider##___##_name(void *__data, _proto);
 200
 201 #undef TRACEPOINT_EVENT_CLASS_NOARGS
 202 #define TRACEPOINT_EVENT_CLASS_NOARGS(_provider, _name, _fields)                             \
 203 static void __event_probe__##_provider##___##_name(void *__data);
 204
 205 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 206
 207 /*
 208  * Stage 3 of the trace events.
 209  *
 210  * Create an array of events.
 211  */
 212
 213 /* Reset all macros within TRACEPOINT_EVENT */
 214 #include <lttng/ust-tracepoint-event-reset.h>
 215
 216 #undef TRACEPOINT_EVENT_INSTANCE_NOARGS
 217 #define TRACEPOINT_EVENT_INSTANCE_NOARGS(_provider, _template, _name)          \
 218                 {                                                              \
 219                         .fields = __event_fields___##_provider##___##_template,\
 220                         .name = #_provider ":" #_name,                         \
 221                         .probe_callback = (void *) &__event_probe__##_provider##___##_template,\
 222                         .nr_fields = _TP_ARRAY_SIZE(__event_fields___##_provider##___##_template), \
 223                 },
 224
 225 #undef TRACEPOINT_EVENT_INSTANCE
 226 #define TRACEPOINT_EVENT_INSTANCE(_provider, _template, _name, _proto, _args)          \
 227         TRACEPOINT_EVENT_INSTANCE_NOARGS(_provider, _template, _name)
 228
 229 #define TP_ID1(_token, _provider)       _token##_provider
 230 #define TP_ID(_token, _provider)        TP_ID1(_token, _provider)
 231
 232 static const struct lttng_event_desc TP_ID(__event_desc___, TRACEPOINT_PROVIDER)[] = {
 233 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 234 };
 235
 236 #undef TP_ID1
 237 #undef TP_ID
 238
 239
 240 /*
 241  * Stage 4 of the trace events.
 242  *
 243  * Create a toplevel descriptor for the whole probe.
 244  */
 245
 246 #define TP_ID1(_token, _provider)       _token##_provider
 247 #define TP_ID(_token, _provider)        TP_ID1(_token, _provider)
 248
 249 /* non-const because list head will be modified when registered. */
 250 static struct lttng_probe_desc TP_ID(__probe_desc___, TRACEPOINT_PROVIDER) = {
 251         .event_desc = TP_ID(__event_desc___, TRACEPOINT_PROVIDER),
 252         .nr_events = _TP_ARRAY_SIZE(TP_ID(__event_desc___, TRACEPOINT_PROVIDER)),
 253 };
 254
 255 #undef TP_ID1
 256 #undef TP_ID
 257
 258 /*
 259  * Stage 5 of the trace events.
 260  *
 261  * Create static inline function that calculates event size.
 262  */
 263
 264 /* Reset all macros within TRACEPOINT_EVENT */
 265 #include <lttng/ust-tracepoint-event-reset.h>
 266
 267 #undef ctf_integer_ext
 268 #define ctf_integer_ext(_type, _item, _src, _byte_order, _base)                \
 269         __event_len += lib_ring_buffer_align(__event_len, lttng_alignof(_type)); \
 270         __event_len += sizeof(_type);
 271
 272 #undef ctf_float
 273 #define ctf_float(_type, _item, _src)                                          \
 274         __event_len += lib_ring_buffer_align(__event_len, lttng_alignof(_type)); \
 275         __event_len += sizeof(_type);
 276
 277 #undef ctf_array_encoded
 278 #define ctf_array_encoded(_type, _item, _src, _length, _encoding)              \
 279         __event_len += lib_ring_buffer_align(__event_len, lttng_alignof(_type)); \
 280         __event_len += sizeof(_type) * (_length);
 281
 282 #undef ctf_sequence_encoded
 283 #define ctf_sequence_encoded(_type, _item, _src, _length_type,  \
 284                         _src_length, _encoding)                 \
 285         __event_len += lib_ring_buffer_align(__event_len, lttng_alignof(_length_type));   \
 286         __event_len += sizeof(_length_type);                                   \
 287         __event_len += lib_ring_buffer_align(__event_len, lttng_alignof(_type)); \
 288         __dynamic_len[__dynamic_len_idx] = (_src_length);                      \
 289         __event_len += sizeof(_type) * __dynamic_len[__dynamic_len_idx];       \
 290         __dynamic_len_idx++;
 291
 292 #undef ctf_string
 293 #define ctf_string(_item, _src)                                                \
 294         __event_len += __dynamic_len[__dynamic_len_idx++] = strlen(_src) + 1;
 295
 296 #undef TP_PROTO
 297 #define TP_PROTO(args...) args
 298
 299 #undef TP_FIELDS
 300 #define TP_FIELDS(args...) args
 301
 302 #undef TRACEPOINT_EVENT_CLASS
 303 #define TRACEPOINT_EVENT_CLASS(_provider, _name, _proto, _args, _fields)      \
 304 static inline size_t __event_get_size__##_provider##___##_name(size_t *__dynamic_len, _proto) \
 305 {                                                                             \
 306         size_t __event_len = 0;                                               \
 307         unsigned int __dynamic_len_idx = 0;                                   \
 308                                                                               \
 309         if (0)                                                                \
 310                 (void) __dynamic_len_idx;       /* don't warn if unused */    \
 311         _fields                                                               \
 312         return __event_len;                                                   \
 313 }
 314
 315 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 316
 317 /*
 318  * Stage 6 of the trace events.
 319  *
 320  * Create static inline function that calculates event payload alignment.
 321  */
 322
 323 /* Reset all macros within TRACEPOINT_EVENT */
 324 #include <lttng/ust-tracepoint-event-reset.h>
 325
 326 #undef ctf_integer_ext
 327 #define ctf_integer_ext(_type, _item, _src, _byte_order, _base)                \
 328         __event_align = _tp_max_t(size_t, __event_align, lttng_alignof(_type));
 329
 330 #undef ctf_float
 331 #define ctf_float(_type, _item, _src)                                          \
 332         __event_align = _tp_max_t(size_t, __event_align, lttng_alignof(_type));
 333
 334 #undef ctf_array_encoded
 335 #define ctf_array_encoded(_type, _item, _src, _length, _encoding)              \
 336         __event_align = _tp_max_t(size_t, __event_align, lttng_alignof(_type));
 337
 338 #undef ctf_sequence_encoded
 339 #define ctf_sequence_encoded(_type, _item, _src, _length_type,  \
 340                         _src_length, _encoding)                 \
 341         __event_align = _tp_max_t(size_t, __event_align, lttng_alignof(_length_type));    \
 342         __event_align = _tp_max_t(size_t, __event_align, lttng_alignof(_type));
 343
 344 #undef ctf_string
 345 #define ctf_string(_item, _src)
 346
 347 #undef TP_PROTO
 348 #define TP_PROTO(args...) args
 349
 350 #undef TP_FIELDS
 351 #define TP_FIELDS(args...) args
 352
 353 #undef TRACEPOINT_EVENT_CLASS
 354 #define TRACEPOINT_EVENT_CLASS(_provider, _name, _proto, _args, _fields)      \
 355 static inline size_t __event_get_align__##_provider##___##_name(_proto)       \
 356 {                                                                             \
 357         size_t __event_align = 1;                                             \
 358         _fields                                                               \
 359         return __event_align;                                                 \
 360 }
 361
 362 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 363
 364
 365 /*
 366  * Stage 7 of the trace events.
 367  *
 368  * Create the probe function : call even size calculation and write event data
 369  * into the buffer.
 370  *
 371  * We use both the field and assignment macros to write the fields in the order
 372  * defined in the field declaration. The field declarations control the
 373  * execution order, jumping to the appropriate assignment block.
 374  */
 375
 376 /* Reset all macros within TRACEPOINT_EVENT */
 377 #include <lttng/ust-tracepoint-event-reset.h>
 378
 379 #undef ctf_integer_ext
 380 #define ctf_integer_ext(_type, _item, _src, _byte_order, _base)         \
 381         {                                                               \
 382                 _type __tmp = (_src);                                   \
 383                 lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(__tmp));\
 384                 __chan->ops->event_write(&__ctx, &__tmp, sizeof(__tmp));\
 385         }
 386
 387 #undef ctf_float
 388 #define ctf_float(_type, _item, _src)                                   \
 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_array_encoded
 396 #define ctf_array_encoded(_type, _item, _src, _length, _encoding)       \
 397         lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(_type));        \
 398         __chan->ops->event_write(&__ctx, _src, sizeof(_type) * (_length));
 399
 400 #undef ctf_sequence_encoded
 401 #define ctf_sequence_encoded(_type, _item, _src, _length_type,          \
 402                         _src_length, _encoding)                 \
 403         {                                                               \
 404                 _length_type __tmpl = __dynamic_len[__dynamic_len_idx]; \
 405                 lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(_length_type));\
 406                 __chan->ops->event_write(&__ctx, &__tmpl, sizeof(_length_type));\
 407         }                                                               \
 408         lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(_type));        \
 409         __chan->ops->event_write(&__ctx, _src,                          \
 410                 sizeof(_type) * __get_dynamic_len(dest));
 411
 412 #undef ctf_string
 413 #define ctf_string(_item, _src)                                         \
 414         lib_ring_buffer_align_ctx(&__ctx, lttng_alignof(*(_src)));      \
 415         __chan->ops->event_write(&__ctx, _src, __get_dynamic_len(dest));
 416
 417 /* Beware: this get len actually consumes the len value */
 418 #undef __get_dynamic_len
 419 #define __get_dynamic_len(field)        __dynamic_len[__dynamic_len_idx++]
 420
 421 #undef TP_PROTO
 422 #define TP_PROTO(args...) args
 423
 424 #undef TP_VARS
 425 #define TP_VARS(args...) args
 426
 427 #undef TP_FIELDS
 428 #define TP_FIELDS(args...) args
 429
 430 #undef TRACEPOINT_EVENT_CLASS
 431 #define TRACEPOINT_EVENT_CLASS(_provider, _name, _proto, _args, _fields)      \
 432 static void __event_probe__##_provider##___##_name(void *__data, _proto)      \
 433 {                                                                             \
 434         struct ltt_event *__event = __data;                                   \
 435         struct ltt_channel *__chan = __event->chan;                           \
 436         struct lttng_ust_lib_ring_buffer_ctx __ctx;                                   \
 437         size_t __event_len, __event_align;                                    \
 438         size_t __dynamic_len_idx = 0;                                         \
 439         size_t __dynamic_len[_TP_ARRAY_SIZE(__event_fields___##_provider##___##_name)];       \
 440         int __ret;                                                            \
 441                                                                               \
 442         if (0)                                                                \
 443                 (void) __dynamic_len_idx;       /* don't warn if unused */    \
 444         if (caa_unlikely(!CMM_ACCESS_ONCE(__chan->session->active)))          \
 445                 return;                                                       \
 446         if (caa_unlikely(!CMM_ACCESS_ONCE(__chan->enabled)))                  \
 447                 return;                                                       \
 448         if (caa_unlikely(!CMM_ACCESS_ONCE(__event->enabled)))                 \
 449                 return;                                                       \
 450         __event_len = __event_get_size__##_provider##___##_name(__dynamic_len, _args);        \
 451         __event_align = __event_get_align__##_provider##___##_name(_args);                    \
 452         lib_ring_buffer_ctx_init(&__ctx, __chan->chan, __event, __event_len,  \
 453                                  __event_align, -1, __chan->handle);          \
 454         __ret = __chan->ops->event_reserve(&__ctx, __event->id);              \
 455         if (__ret < 0)                                                        \
 456                 return;                                                       \
 457         _fields                                                               \
 458         __chan->ops->event_commit(&__ctx);                                    \
 459 }
 460
 461 #undef TRACEPOINT_EVENT_CLASS_NOARGS
 462 #define TRACEPOINT_EVENT_CLASS_NOARGS(_provider, _name, _fields)              \
 463 static void __event_probe__##_provider##___##_name(void *__data)              \
 464 {                                                                             \
 465         struct ltt_event *__event = __data;                                   \
 466         struct ltt_channel *__chan = __event->chan;                           \
 467         struct lttng_ust_lib_ring_buffer_ctx __ctx;                                   \
 468         size_t __event_len, __event_align;                                    \
 469         int __ret;                                                            \
 470                                                                               \
 471         if (caa_unlikely(!CMM_ACCESS_ONCE(__chan->session->active)))          \
 472                 return;                                                       \
 473         if (caa_unlikely(!CMM_ACCESS_ONCE(__chan->enabled)))                  \
 474                 return;                                                       \
 475         if (caa_unlikely(!CMM_ACCESS_ONCE(__event->enabled)))                 \
 476                 return;                                                       \
 477         __event_len = 0;                                                      \
 478         __event_align = 1;                                                    \
 479         lib_ring_buffer_ctx_init(&__ctx, __chan->chan, __event, __event_len,  \
 480                                  __event_align, -1, __chan->handle);          \
 481         __ret = __chan->ops->event_reserve(&__ctx, __event->id);              \
 482         if (__ret < 0)                                                        \
 483                 return;                                                       \
 484         _fields                                                               \
 485         __chan->ops->event_commit(&__ctx);                                    \
 486 }
 487
 488 #include TRACEPOINT_INCLUDE(TRACEPOINT_INCLUDE_FILE)
 489
 490 #undef __get_dynamic_len
 491
 492 /*
 493  * Stage 8 of the trace events.
 494  *
 495  * Register/unregister probes at module load/unload.
 496  */
 497
 498 /* Reset all macros within TRACEPOINT_EVENT */
 499 #include <lttng/ust-tracepoint-event-reset.h>
 500
 501 #define TP_ID1(_token, _provider)       _token##_provider
 502 #define TP_ID(_token, _provider)        TP_ID1(_token, _provider)
 503
 504 static void __attribute__((constructor))
 505 TP_ID(__lttng_events_init__, TRACEPOINT_PROVIDER)(void)
 506 {
 507         int ret;
 508
 509         ret = ltt_probe_register(&TP_ID(__probe_desc___, TRACEPOINT_PROVIDER));
 510         assert(!ret);
 511 }
 512
 513 static void __attribute__((destructor))
 514 TP_ID(__lttng_events_exit__, TRACEPOINT_PROVIDER)(void)
 515 {
 516         ltt_probe_unregister(&TP_ID(__probe_desc___, TRACEPOINT_PROVIDER));
 517 }
 518
 519 #undef TP_ID1
 520 #undef TP_ID