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