include/lttng/ust-events.h

   1 #ifndef _LTTNG_UST_EVENTS_H
   2 #define _LTTNG_UST_EVENTS_H
   3
   4 /*
   5  * lttng/ust-events.h
   6  *
   7  * Copyright 2010-2012 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   8  *
   9  * Holds LTTng per-session event registry.
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a copy
  12  * of this software and associated documentation files (the "Software"), to deal
  13  * in the Software without restriction, including without limitation the rights
  14  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  15  * copies of the Software, and to permit persons to whom the Software is
  16  * furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included in
  19  * all copies or substantial portions of the Software.
  20  *
  21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  22  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  23  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  24  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  25  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  26  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  27  * SOFTWARE.
  28  */
  29
  30 #include <urcu/list.h>
  31 #include <urcu/hlist.h>
  32 #include <stdint.h>
  33 #include <lttng/ust-abi.h>
  34 #include <lttng/ust-tracer.h>
  35 #include <lttng/ust-endian.h>
  36 #include <float.h>
  37
  38 #define LTTNG_UST_UUID_LEN              16
  39
  40 /*
  41  * Tracepoint provider version. Compatibility based on the major number.
  42  * Older tracepoint providers can always register to newer lttng-ust
  43  * library, but the opposite is rejected: a newer tracepoint provider is
  44  * rejected by an older lttng-ust library.
  45  */
  46 #define LTTNG_UST_PROVIDER_MAJOR        1
  47 #define LTTNG_UST_PROVIDER_MINOR        0
  48
  49 struct lttng_channel;
  50 struct lttng_session;
  51 struct lttng_ust_lib_ring_buffer_ctx;
  52
  53 /*
  54  * Data structures used by tracepoint event declarations, and by the
  55  * tracer. Those structures have padding for future extension.
  56  */
  57
  58 /*
  59  * LTTng client type enumeration. Used by the consumer to map the
  60  * callbacks from its own address space.
  61  */
  62 enum lttng_client_types {
  63         LTTNG_CLIENT_METADATA = 0,
  64         LTTNG_CLIENT_DISCARD = 1,
  65         LTTNG_CLIENT_OVERWRITE = 2,
  66         LTTNG_CLIENT_DISCARD_RT = 3,
  67         LTTNG_CLIENT_OVERWRITE_RT = 4,
  68         LTTNG_NR_CLIENT_TYPES,
  69 };
  70
  71 /* Type description */
  72
  73 /* Update the astract_types name table in lttng-types.c along with this enum */
  74 enum lttng_abstract_types {
  75         atype_integer,
  76         atype_enum,
  77         atype_array,
  78         atype_sequence,
  79         atype_string,
  80         atype_float,
  81         NR_ABSTRACT_TYPES,
  82 };
  83
  84 /* Update the string_encodings name table in lttng-types.c along with this enum */
  85 enum lttng_string_encodings {
  86         lttng_encode_none = 0,
  87         lttng_encode_UTF8 = 1,
  88         lttng_encode_ASCII = 2,
  89         NR_STRING_ENCODINGS,
  90 };
  91
  92 #define LTTNG_UST_ENUM_ENTRY_PADDING    16
  93 struct lttng_enum_entry {
  94         unsigned long long start, end;  /* start and end are inclusive */
  95         const char *string;
  96         char padding[LTTNG_UST_ENUM_ENTRY_PADDING];
  97 };
  98
  99 #define __type_integer(_type, _byte_order, _base, _encoding)    \
 100         {                                                       \
 101             .atype = atype_integer,                             \
 102             .u.basic.integer =                                  \
 103                 {                                               \
 104                   .size = sizeof(_type) * CHAR_BIT,             \
 105                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
 106                   .signedness = lttng_is_signed_type(_type),    \
 107                   .reverse_byte_order = _byte_order != BYTE_ORDER,      \
 108                   .base = _base,                                \
 109                   .encoding = lttng_encode_##_encoding,         \
 110                 },                                              \
 111         }                                                       \
 112
 113 #define LTTNG_UST_INTEGER_TYPE_PADDING  24
 114 struct lttng_integer_type {
 115         unsigned int size;              /* in bits */
 116         unsigned short alignment;       /* in bits */
 117         unsigned int signedness:1;
 118         unsigned int reverse_byte_order:1;
 119         unsigned int base;              /* 2, 8, 10, 16, for pretty print */
 120         enum lttng_string_encodings encoding;
 121         char padding[LTTNG_UST_INTEGER_TYPE_PADDING];
 122 };
 123
 124 /*
 125  * Only float and double are supported. long double is not supported at
 126  * the moment.
 127  */
 128 #define _float_mant_dig(_type)                                          \
 129         (sizeof(_type) == sizeof(float) ? FLT_MANT_DIG                  \
 130                 : (sizeof(_type) == sizeof(double) ? DBL_MANT_DIG       \
 131                 : 0))
 132
 133 #define __type_float(_type)                                     \
 134         {                                                       \
 135             .atype = atype_float,                               \
 136             .u.basic._float =                                   \
 137                 {                                               \
 138                   .exp_dig = sizeof(_type) * CHAR_BIT           \
 139                                 - _float_mant_dig(_type),       \
 140                   .mant_dig = _float_mant_dig(_type),           \
 141                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
 142                   .reverse_byte_order = BYTE_ORDER != FLOAT_WORD_ORDER, \
 143                 },                                              \
 144         }                                                       \
 145
 146 #define LTTNG_UST_FLOAT_TYPE_PADDING    24
 147 struct lttng_float_type {
 148         unsigned int exp_dig;           /* exponent digits, in bits */
 149         unsigned int mant_dig;          /* mantissa digits, in bits */
 150         unsigned short alignment;       /* in bits */
 151         unsigned int reverse_byte_order:1;
 152         char padding[LTTNG_UST_FLOAT_TYPE_PADDING];
 153 };
 154
 155 #define LTTNG_UST_BASIC_TYPE_PADDING    128
 156 union _lttng_basic_type {
 157         struct lttng_integer_type integer;
 158         struct {
 159                 const char *name;
 160         } enumeration;
 161         struct {
 162                 enum lttng_string_encodings encoding;
 163         } string;
 164         struct lttng_float_type _float;
 165         char padding[LTTNG_UST_BASIC_TYPE_PADDING];
 166 };
 167
 168 struct lttng_basic_type {
 169         enum lttng_abstract_types atype;
 170         union {
 171                 union _lttng_basic_type basic;
 172         } u;
 173 };
 174
 175 #define LTTNG_UST_TYPE_PADDING  128
 176 struct lttng_type {
 177         enum lttng_abstract_types atype;
 178         union {
 179                 union _lttng_basic_type basic;
 180                 struct {
 181                         struct lttng_basic_type elem_type;
 182                         unsigned int length;            /* num. elems. */
 183                 } array;
 184                 struct {
 185                         struct lttng_basic_type length_type;
 186                         struct lttng_basic_type elem_type;
 187                 } sequence;
 188                 char padding[LTTNG_UST_TYPE_PADDING];
 189         } u;
 190 };
 191
 192 #define LTTNG_UST_ENUM_TYPE_PADDING     24
 193 struct lttng_enum {
 194         const char *name;
 195         struct lttng_type container_type;
 196         const struct lttng_enum_entry *entries;
 197         unsigned int len;
 198         char padding[LTTNG_UST_ENUM_TYPE_PADDING];
 199 };
 200
 201 /*
 202  * Event field description
 203  *
 204  * IMPORTANT: this structure is part of the ABI between the probe and
 205  * UST. Fields need to be only added at the end, never reordered, never
 206  * removed.
 207  */
 208
 209 #define LTTNG_UST_EVENT_FIELD_PADDING   28
 210 struct lttng_event_field {
 211         const char *name;
 212         struct lttng_type type;
 213         unsigned int nowrite;   /* do not write into trace */
 214         char padding[LTTNG_UST_EVENT_FIELD_PADDING];
 215 };
 216
 217 union lttng_ctx_value {
 218         int64_t s64;
 219         const char *str;
 220         double d;
 221 };
 222
 223 #define LTTNG_UST_CTX_FIELD_PADDING     40
 224 struct lttng_ctx_field {
 225         struct lttng_event_field event_field;
 226         size_t (*get_size)(size_t offset);
 227         void (*record)(struct lttng_ctx_field *field,
 228                        struct lttng_ust_lib_ring_buffer_ctx *ctx,
 229                        struct lttng_channel *chan);
 230         void (*get_value)(struct lttng_ctx_field *field,
 231                          union lttng_ctx_value *value);
 232         union {
 233                 char padding[LTTNG_UST_CTX_FIELD_PADDING];
 234         } u;
 235         void (*destroy)(struct lttng_ctx_field *field);
 236 };
 237
 238 #define LTTNG_UST_CTX_PADDING   24
 239 struct lttng_ctx {
 240         struct lttng_ctx_field *fields;
 241         unsigned int nr_fields;
 242         unsigned int allocated_fields;
 243         char padding[LTTNG_UST_CTX_PADDING];
 244 };
 245
 246 #define LTTNG_UST_EVENT_DESC_PADDING    40
 247 struct lttng_event_desc {
 248         const char *name;
 249         void (*probe_callback)(void);
 250         const struct lttng_event_ctx *ctx;      /* context */
 251         const struct lttng_event_field *fields; /* event payload */
 252         unsigned int nr_fields;
 253         const int **loglevel;
 254         const char *signature;  /* Argument types/names received */
 255         union {
 256                 struct {
 257                         const char **model_emf_uri;
 258                 } ext;
 259                 char padding[LTTNG_UST_EVENT_DESC_PADDING];
 260         } u;
 261 };
 262
 263 #define LTTNG_UST_PROBE_DESC_PADDING    12
 264 struct lttng_probe_desc {
 265         const char *provider;
 266         const struct lttng_event_desc **event_desc;
 267         unsigned int nr_events;
 268         struct cds_list_head head;              /* chain registered probes */
 269         struct cds_list_head lazy_init_head;
 270         int lazy;                               /* lazy registration */
 271         uint32_t major;
 272         uint32_t minor;
 273         char padding[LTTNG_UST_PROBE_DESC_PADDING];
 274 };
 275
 276 /* Data structures used by the tracer. */
 277
 278 enum lttng_enabler_type {
 279         LTTNG_ENABLER_WILDCARD,
 280         LTTNG_ENABLER_EVENT,
 281 };
 282
 283 /*
 284  * Enabler field, within whatever object is enabling an event. Target of
 285  * backward reference.
 286  */
 287 struct lttng_enabler {
 288         enum lttng_enabler_type type;
 289
 290         /* head list of struct lttng_ust_filter_bytecode_node */
 291         struct cds_list_head filter_bytecode_head;
 292         struct cds_list_head node;      /* per-session list of enablers */
 293
 294         struct lttng_ust_event event_param;
 295         struct lttng_channel *chan;
 296         struct lttng_ctx *ctx;
 297         unsigned int enabled:1;
 298 };
 299
 300 struct tp_list_entry {
 301         struct lttng_ust_tracepoint_iter tp;
 302         struct cds_list_head head;
 303 };
 304
 305 struct lttng_ust_tracepoint_list {
 306         struct tp_list_entry *iter;
 307         struct cds_list_head head;
 308 };
 309
 310 struct tp_field_list_entry {
 311         struct lttng_ust_field_iter field;
 312         struct cds_list_head head;
 313 };
 314
 315 struct lttng_ust_field_list {
 316         struct tp_field_list_entry *iter;
 317         struct cds_list_head head;
 318 };
 319
 320 struct ust_pending_probe;
 321 struct lttng_event;
 322
 323 struct lttng_ust_filter_bytecode_node {
 324         struct cds_list_head node;
 325         struct lttng_enabler *enabler;
 326         /*
 327          * struct lttng_ust_filter_bytecode has var. sized array, must
 328          * be last field.
 329          */
 330         struct lttng_ust_filter_bytecode bc;
 331 };
 332
 333 /*
 334  * Filter return value masks.
 335  */
 336 enum lttng_filter_ret {
 337         LTTNG_FILTER_DISCARD = 0,
 338         LTTNG_FILTER_RECORD_FLAG = (1ULL << 0),
 339         /* Other bits are kept for future use. */
 340 };
 341
 342 struct lttng_bytecode_runtime {
 343         /* Associated bytecode */
 344         struct lttng_ust_filter_bytecode_node *bc;
 345         uint64_t (*filter)(void *filter_data, const char *filter_stack_data);
 346         int link_failed;
 347         struct cds_list_head node;      /* list of bytecode runtime in event */
 348 };
 349
 350 /*
 351  * Objects in a linked-list of enablers, owned by an event.
 352  */
 353 struct lttng_enabler_ref {
 354         struct cds_list_head node;              /* enabler ref list */
 355         struct lttng_enabler *ref;              /* backward ref */
 356 };
 357
 358 /*
 359  * lttng_event structure is referred to by the tracing fast path. It
 360  * must be kept small.
 361  *
 362  * IMPORTANT: this structure is part of the ABI between the probe and
 363  * UST. Fields need to be only added at the end, never reordered, never
 364  * removed.
 365  */
 366 struct lttng_event {
 367         /* LTTng-UST 2.0 starts here */
 368         unsigned int id;
 369         struct lttng_channel *chan;
 370         int enabled;
 371         const struct lttng_event_desc *desc;
 372         void *_deprecated1;
 373         struct lttng_ctx *ctx;
 374         enum lttng_ust_instrumentation instrumentation;
 375         union {
 376         } u;
 377         struct cds_list_head node;              /* Event list in session */
 378         struct cds_list_head _deprecated2;
 379         void *_deprecated3;
 380         unsigned int _deprecated4:1;
 381
 382         /* LTTng-UST 2.1 starts here */
 383         /* list of struct lttng_bytecode_runtime, sorted by seqnum */
 384         struct cds_list_head bytecode_runtime_head;
 385         int has_enablers_without_bytecode;
 386         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 387         struct cds_list_head enablers_ref_head;
 388         struct cds_hlist_node hlist;    /* session ht of events */
 389         int registered;                 /* has reg'd tracepoint probe */
 390 };
 391
 392 struct channel;
 393 struct lttng_ust_shm_handle;
 394
 395 /*
 396  * IMPORTANT: this structure is part of the ABI between the probe and
 397  * UST. Fields need to be only added at the end, never reordered, never
 398  * removed.
 399  */
 400 struct lttng_channel_ops {
 401         struct lttng_channel *(*channel_create)(const char *name,
 402                         void *buf_addr,
 403                         size_t subbuf_size, size_t num_subbuf,
 404                         unsigned int switch_timer_interval,
 405                         unsigned int read_timer_interval,
 406                         unsigned char *uuid,
 407                         uint32_t chan_id);
 408         void (*channel_destroy)(struct lttng_channel *chan);
 409         void *_deprecated1;
 410         void *_deprecated2;
 411         int (*event_reserve)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 412                              uint32_t event_id);
 413         void (*event_commit)(struct lttng_ust_lib_ring_buffer_ctx *ctx);
 414         void (*event_write)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 415                         const void *src, size_t len);
 416         /*
 417          * packet_avail_size returns the available size in the current
 418          * packet. Note that the size returned is only a hint, since it
 419          * may change due to concurrent writes.
 420          */
 421         size_t (*packet_avail_size)(struct channel *chan,
 422                                     struct lttng_ust_shm_handle *handle);
 423         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 424         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 425         int (*is_finalized)(struct channel *chan);
 426         int (*is_disabled)(struct channel *chan);
 427         int (*flush_buffer)(struct channel *chan, struct lttng_ust_shm_handle *handle);
 428 };
 429
 430 /*
 431  * IMPORTANT: this structure is part of the ABI between the probe and
 432  * UST. Fields need to be only added at the end, never reordered, never
 433  * removed.
 434  */
 435 struct lttng_channel {
 436         /*
 437          * The pointers located in this private data are NOT safe to be
 438          * dereferenced by the consumer. The only operations the
 439          * consumer process is designed to be allowed to do is to read
 440          * and perform subbuffer flush.
 441          */
 442         struct channel *chan;           /* Channel buffers */
 443         int enabled;
 444         struct lttng_ctx *ctx;
 445         /* Event ID management */
 446         struct lttng_session *session;
 447         int objd;                       /* Object associated to channel */
 448         unsigned int _deprecated1;
 449         unsigned int _deprecated2;
 450         struct cds_list_head node;      /* Channel list in session */
 451         const struct lttng_channel_ops *ops;
 452         int header_type;                /* 0: unset, 1: compact, 2: large */
 453         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
 454         unsigned int _deprecated3:1;
 455
 456         /* Channel ID */
 457         unsigned int id;
 458         enum lttng_ust_chan_type type;
 459         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 460         int tstate:1;                   /* Transient enable state */
 461 };
 462
 463 #define LTTNG_UST_EVENT_HT_BITS         12
 464 #define LTTNG_UST_EVENT_HT_SIZE         (1U << LTTNG_UST_EVENT_HT_BITS)
 465
 466 struct lttng_ust_event_ht {
 467         struct cds_hlist_head table[LTTNG_UST_EVENT_HT_SIZE];
 468 };
 469
 470 /*
 471  * IMPORTANT: this structure is part of the ABI between the probe and
 472  * UST. Fields need to be only added at the end, never reordered, never
 473  * removed.
 474  */
 475 struct lttng_session {
 476         int active;                             /* Is trace session active ? */
 477         int been_active;                        /* Been active ? */
 478         int objd;                               /* Object associated */
 479         void *_deprecated1;
 480         struct cds_list_head chan_head;         /* Channel list head */
 481         struct cds_list_head events_head;       /* list of events */
 482         struct cds_list_head _deprecated2;
 483         struct cds_list_head node;              /* Session list */
 484         int _deprecated3;
 485         unsigned int _deprecated4:1;
 486
 487         /* New UST 2.1 */
 488         /* List of enablers */
 489         struct cds_list_head enablers_head;
 490         struct lttng_ust_event_ht events_ht;    /* ht of events */
 491         void *owner;                            /* object owner */
 492         int tstate:1;                           /* Transient enable state */
 493 };
 494
 495 struct lttng_transport {
 496         char *name;
 497         struct cds_list_head node;
 498         struct lttng_channel_ops ops;
 499         const struct lttng_ust_lib_ring_buffer_config *client_config;
 500 };
 501
 502 struct lttng_session *lttng_session_create(void);
 503 int lttng_session_enable(struct lttng_session *session);
 504 int lttng_session_disable(struct lttng_session *session);
 505 void lttng_session_destroy(struct lttng_session *session);
 506
 507 struct lttng_channel *lttng_channel_create(struct lttng_session *session,
 508                                        const char *transport_name,
 509                                        void *buf_addr,
 510                                        size_t subbuf_size, size_t num_subbuf,
 511                                        unsigned int switch_timer_interval,
 512                                        unsigned int read_timer_interval,
 513                                        int **shm_fd, int **wait_fd,
 514                                        uint64_t **memory_map_size,
 515                                        struct lttng_channel *chan_priv_init);
 516
 517 int lttng_channel_enable(struct lttng_channel *channel);
 518 int lttng_channel_disable(struct lttng_channel *channel);
 519
 520 struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type,
 521                 struct lttng_ust_event *event_param,
 522                 struct lttng_channel *chan);
 523 int lttng_enabler_enable(struct lttng_enabler *enabler);
 524 int lttng_enabler_disable(struct lttng_enabler *enabler);
 525 int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
 526                 struct lttng_ust_filter_bytecode_node *bytecode);
 527 int lttng_enabler_attach_context(struct lttng_enabler *enabler,
 528                 struct lttng_ust_context *ctx);
 529
 530 int lttng_attach_context(struct lttng_ust_context *context_param,
 531                 struct lttng_ctx **ctx, struct lttng_session *session);
 532 void lttng_context_init(void);
 533 void lttng_context_exit(void);
 534 extern struct lttng_ctx *lttng_static_ctx;      /* Used by filtering */
 535
 536 void lttng_transport_register(struct lttng_transport *transport);
 537 void lttng_transport_unregister(struct lttng_transport *transport);
 538
 539 void synchronize_trace(void);
 540
 541 int lttng_probe_register(struct lttng_probe_desc *desc);
 542 void lttng_probe_unregister(struct lttng_probe_desc *desc);
 543 int lttng_fix_pending_events(void);
 544 int lttng_probes_init(void);
 545 void lttng_probes_exit(void);
 546 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 547 int lttng_get_context_index(struct lttng_ctx *ctx, const char *name);
 548 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p);
 549 void lttng_remove_context_field(struct lttng_ctx **ctx_p,
 550                                 struct lttng_ctx_field *field);
 551 void lttng_destroy_context(struct lttng_ctx *ctx);
 552 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 553 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 554 int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
 555 int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
 556 void lttng_context_vtid_reset(void);
 557 void lttng_context_vpid_reset(void);
 558
 559 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
 560 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
 561 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;
 562
 563 struct lttng_transport *lttng_transport_find(const char *name);
 564
 565 int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
 566 void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
 567 struct lttng_ust_tracepoint_iter *
 568         lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
 569 int lttng_probes_get_field_list(struct lttng_ust_field_list *list);
 570 void lttng_probes_prune_field_list(struct lttng_ust_field_list *list);
 571 struct lttng_ust_field_iter *
 572         lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list);
 573
 574 void lttng_filter_event_link_bytecode(struct lttng_event *event);
 575 void lttng_enabler_event_link_bytecode(struct lttng_event *event,
 576                 struct lttng_enabler *enabler);
 577 void lttng_free_event_filter_runtime(struct lttng_event *event);
 578 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime);
 579
 580 struct cds_list_head *lttng_get_probe_list_head(void);
 581 int lttng_session_active(void);
 582
 583 #endif /* _LTTNG_UST_EVENTS_H */