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
  22 #include <urcu/list.h>
  23 #include <urcu/hlist.h>
  24 #include <stdint.h>
  25 #include <lttng/ust-abi.h>
  26 #include <lttng/ust-tracer.h>
  27 #include <lttng/ust-endian.h>
  28 #include <float.h>
  29
  30 #define LTTNG_UST_UUID_LEN              16
  31
  32 struct lttng_channel;
  33 struct lttng_session;
  34 struct lttng_ust_lib_ring_buffer_ctx;
  35
  36 /*
  37  * Data structures used by tracepoint event declarations, and by the
  38  * tracer. Those structures have padding for future extension.
  39  */
  40
  41 /*
  42  * LTTng client type enumeration. Used by the consumer to map the
  43  * callbacks from its own address space.
  44  */
  45 enum lttng_client_types {
  46         LTTNG_CLIENT_METADATA = 0,
  47         LTTNG_CLIENT_DISCARD = 1,
  48         LTTNG_CLIENT_OVERWRITE = 2,
  49         LTTNG_NR_CLIENT_TYPES,
  50 };
  51
  52 /* Type description */
  53
  54 /* Update the astract_types name table in lttng-types.c along with this enum */
  55 enum lttng_abstract_types {
  56         atype_integer,
  57         atype_enum,
  58         atype_array,
  59         atype_sequence,
  60         atype_string,
  61         atype_float,
  62         NR_ABSTRACT_TYPES,
  63 };
  64
  65 /* Update the string_encodings name table in lttng-types.c along with this enum */
  66 enum lttng_string_encodings {
  67         lttng_encode_none = 0,
  68         lttng_encode_UTF8 = 1,
  69         lttng_encode_ASCII = 2,
  70         NR_STRING_ENCODINGS,
  71 };
  72
  73 #define LTTNG_UST_ENUM_ENTRY_PADDING    16
  74 struct lttng_enum_entry {
  75         unsigned long long start, end;  /* start and end are inclusive */
  76         const char *string;
  77         char padding[LTTNG_UST_ENUM_ENTRY_PADDING];
  78 };
  79
  80 #define __type_integer(_type, _byte_order, _base, _encoding)    \
  81         {                                                       \
  82             .atype = atype_integer,                             \
  83             .u.basic.integer =                                  \
  84                 {                                               \
  85                   .size = sizeof(_type) * CHAR_BIT,             \
  86                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
  87                   .signedness = lttng_is_signed_type(_type),    \
  88                   .reverse_byte_order = _byte_order != BYTE_ORDER,      \
  89                   .base = _base,                                \
  90                   .encoding = lttng_encode_##_encoding,         \
  91                 },                                              \
  92         }                                                       \
  93
  94 #define LTTNG_UST_INTEGER_TYPE_PADDING  24
  95 struct lttng_integer_type {
  96         unsigned int size;              /* in bits */
  97         unsigned short alignment;       /* in bits */
  98         unsigned int signedness:1;
  99         unsigned int reverse_byte_order:1;
 100         unsigned int base;              /* 2, 8, 10, 16, for pretty print */
 101         enum lttng_string_encodings encoding;
 102         char padding[LTTNG_UST_INTEGER_TYPE_PADDING];
 103 };
 104
 105 /*
 106  * Only float and double are supported. long double is not supported at
 107  * the moment.
 108  */
 109 #define _float_mant_dig(_type)                                          \
 110         (sizeof(_type) == sizeof(float) ? FLT_MANT_DIG                  \
 111                 : (sizeof(_type) == sizeof(double) ? DBL_MANT_DIG       \
 112                 : 0))
 113
 114 #define __type_float(_type)                                     \
 115         {                                                       \
 116             .atype = atype_float,                               \
 117             .u.basic._float =                                   \
 118                 {                                               \
 119                   .exp_dig = sizeof(_type) * CHAR_BIT           \
 120                                 - _float_mant_dig(_type),       \
 121                   .mant_dig = _float_mant_dig(_type),           \
 122                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
 123                   .reverse_byte_order = BYTE_ORDER != FLOAT_WORD_ORDER, \
 124                 },                                              \
 125         }                                                       \
 126
 127 #define LTTNG_UST_FLOAT_TYPE_PADDING    24
 128 struct lttng_float_type {
 129         unsigned int exp_dig;           /* exponent digits, in bits */
 130         unsigned int mant_dig;          /* mantissa digits, in bits */
 131         unsigned short alignment;       /* in bits */
 132         unsigned int reverse_byte_order:1;
 133         char padding[LTTNG_UST_FLOAT_TYPE_PADDING];
 134 };
 135
 136 #define LTTNG_UST_BASIC_TYPE_PADDING    128
 137 union _lttng_basic_type {
 138         struct lttng_integer_type integer;
 139         struct {
 140                 const char *name;
 141         } enumeration;
 142         struct {
 143                 enum lttng_string_encodings encoding;
 144         } string;
 145         struct lttng_float_type _float;
 146         char padding[LTTNG_UST_BASIC_TYPE_PADDING];
 147 };
 148
 149 struct lttng_basic_type {
 150         enum lttng_abstract_types atype;
 151         union {
 152                 union _lttng_basic_type basic;
 153         } u;
 154 };
 155
 156 #define LTTNG_UST_TYPE_PADDING  128
 157 struct lttng_type {
 158         enum lttng_abstract_types atype;
 159         union {
 160                 union _lttng_basic_type basic;
 161                 struct {
 162                         struct lttng_basic_type elem_type;
 163                         unsigned int length;            /* num. elems. */
 164                 } array;
 165                 struct {
 166                         struct lttng_basic_type length_type;
 167                         struct lttng_basic_type elem_type;
 168                 } sequence;
 169                 char padding[LTTNG_UST_TYPE_PADDING];
 170         } u;
 171 };
 172
 173 #define LTTNG_UST_ENUM_TYPE_PADDING     24
 174 struct lttng_enum {
 175         const char *name;
 176         struct lttng_type container_type;
 177         const struct lttng_enum_entry *entries;
 178         unsigned int len;
 179         char padding[LTTNG_UST_ENUM_TYPE_PADDING];
 180 };
 181
 182 /*
 183  * Event field description
 184  *
 185  * IMPORTANT: this structure is part of the ABI between the probe and
 186  * UST. Fields need to be only added at the end, never reordered, never
 187  * removed.
 188  */
 189
 190 #define LTTNG_UST_EVENT_FIELD_PADDING   28
 191 struct lttng_event_field {
 192         const char *name;
 193         struct lttng_type type;
 194         unsigned int nowrite;   /* do not write into trace */
 195         char padding[LTTNG_UST_EVENT_FIELD_PADDING];
 196 };
 197
 198 #define LTTNG_UST_CTX_FIELD_PADDING     40
 199 struct lttng_ctx_field {
 200         struct lttng_event_field event_field;
 201         size_t (*get_size)(size_t offset);
 202         void (*record)(struct lttng_ctx_field *field,
 203                        struct lttng_ust_lib_ring_buffer_ctx *ctx,
 204                        struct lttng_channel *chan);
 205         union {
 206                 char padding[LTTNG_UST_CTX_FIELD_PADDING];
 207         } u;
 208         void (*destroy)(struct lttng_ctx_field *field);
 209 };
 210
 211 #define LTTNG_UST_CTX_PADDING   24
 212 struct lttng_ctx {
 213         struct lttng_ctx_field *fields;
 214         unsigned int nr_fields;
 215         unsigned int allocated_fields;
 216         char padding[LTTNG_UST_CTX_PADDING];
 217 };
 218
 219 #define LTTNG_UST_EVENT_DESC_PADDING    40
 220 struct lttng_event_desc {
 221         const char *name;
 222         void (*probe_callback)(void);
 223         const struct lttng_event_ctx *ctx;      /* context */
 224         const struct lttng_event_field *fields; /* event payload */
 225         unsigned int nr_fields;
 226         const int **loglevel;
 227         const char *signature;  /* Argument types/names received */
 228         union {
 229                 struct {
 230                         const char **model_emf_uri;
 231                 } ext;
 232                 char padding[LTTNG_UST_EVENT_DESC_PADDING];
 233         } u;
 234 };
 235
 236 #define LTTNG_UST_PROBE_DESC_PADDING    40
 237 struct lttng_probe_desc {
 238         const char *provider;
 239         const struct lttng_event_desc **event_desc;
 240         unsigned int nr_events;
 241         struct cds_list_head head;              /* chain registered probes */
 242         char padding[LTTNG_UST_PROBE_DESC_PADDING];
 243 };
 244
 245 /* Data structures used by the tracer. */
 246
 247 enum lttng_enabler_type {
 248         LTTNG_ENABLER_WILDCARD,
 249         LTTNG_ENABLER_EVENT,
 250 };
 251
 252 /*
 253  * Enabler field, within whatever object is enabling an event. Target of
 254  * backward reference.
 255  */
 256 struct lttng_enabler {
 257         enum lttng_enabler_type type;
 258
 259         /* head list of struct lttng_ust_filter_bytecode_node */
 260         struct cds_list_head filter_bytecode_head;
 261         struct cds_list_head node;      /* per-session list of enablers */
 262
 263         struct lttng_ust_event event_param;
 264         struct lttng_channel *chan;
 265         struct lttng_ctx *ctx;
 266         unsigned int enabled:1;
 267 };
 268
 269 struct tp_list_entry {
 270         struct lttng_ust_tracepoint_iter tp;
 271         struct cds_list_head head;
 272 };
 273
 274 struct lttng_ust_tracepoint_list {
 275         struct tp_list_entry *iter;
 276         struct cds_list_head head;
 277 };
 278
 279 struct tp_field_list_entry {
 280         struct lttng_ust_field_iter field;
 281         struct cds_list_head head;
 282 };
 283
 284 struct lttng_ust_field_list {
 285         struct tp_field_list_entry *iter;
 286         struct cds_list_head head;
 287 };
 288
 289 struct ust_pending_probe;
 290 struct lttng_event;
 291
 292 struct lttng_ust_filter_bytecode_node {
 293         struct cds_list_head node;
 294         struct lttng_enabler *enabler;
 295         /*
 296          * struct lttng_ust_filter_bytecode has var. sized array, must
 297          * be last field.
 298          */
 299         struct lttng_ust_filter_bytecode bc;
 300 };
 301
 302 struct lttng_bytecode_runtime {
 303         /* Associated bytecode */
 304         struct lttng_ust_filter_bytecode_node *bc;
 305         int (*filter)(void *filter_data, const char *filter_stack_data);
 306         int link_failed;
 307         struct cds_list_head node;      /* list of bytecode runtime in event */
 308 };
 309
 310 /*
 311  * Objects in a linked-list of enablers, owned by an event.
 312  */
 313 struct lttng_enabler_ref {
 314         struct cds_list_head node;              /* enabler ref list */
 315         struct lttng_enabler *ref;              /* backward ref */
 316 };
 317
 318 /*
 319  * lttng_event structure is referred to by the tracing fast path. It
 320  * must be kept small.
 321  *
 322  * IMPORTANT: this structure is part of the ABI between the probe and
 323  * UST. Fields need to be only added at the end, never reordered, never
 324  * removed.
 325  */
 326 struct lttng_event {
 327         /* LTTng-UST 2.0 starts here */
 328         unsigned int id;
 329         struct lttng_channel *chan;
 330         int enabled;
 331         const struct lttng_event_desc *desc;
 332         void *_deprecated1;
 333         struct lttng_ctx *ctx;
 334         enum lttng_ust_instrumentation instrumentation;
 335         union {
 336         } u;
 337         struct cds_list_head node;              /* Event list in session */
 338         struct cds_list_head _deprecated2;
 339         void *_deprecated3;
 340         unsigned int metadata_dumped:1;
 341
 342         /* LTTng-UST 2.1 starts here */
 343         /* list of struct lttng_bytecode_runtime, sorted by seqnum */
 344         struct cds_list_head bytecode_runtime_head;
 345
 346         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 347         struct cds_list_head enablers_ref_head;
 348 };
 349
 350 struct channel;
 351 struct lttng_ust_shm_handle;
 352
 353 /*
 354  * IMPORTANT: this structure is part of the ABI between the probe and
 355  * UST. Fields need to be only added at the end, never reordered, never
 356  * removed.
 357  */
 358 struct lttng_channel_ops {
 359         struct lttng_channel *(*channel_create)(const char *name,
 360                                 void *buf_addr,
 361                                 size_t subbuf_size, size_t num_subbuf,
 362                                 unsigned int switch_timer_interval,
 363                                 unsigned int read_timer_interval,
 364                                 int **shm_fd, int **wait_fd,
 365                                 uint64_t **memory_map_size,
 366                                 struct lttng_channel *chan_priv_init);
 367         void (*channel_destroy)(struct lttng_channel *lttng_chan);
 368         struct lttng_ust_lib_ring_buffer *(*buffer_read_open)(struct channel *chan,
 369                                 struct lttng_ust_shm_handle *handle,
 370                                 int **shm_fd, int **wait_fd,
 371                                 uint64_t **memory_map_size);
 372         void (*buffer_read_close)(struct lttng_ust_lib_ring_buffer *buf,
 373                                 struct lttng_ust_shm_handle *handle);
 374         int (*event_reserve)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 375                              uint32_t event_id);
 376         void (*event_commit)(struct lttng_ust_lib_ring_buffer_ctx *ctx);
 377         void (*event_write)(struct lttng_ust_lib_ring_buffer_ctx *ctx, const void *src,
 378                             size_t len);
 379         /*
 380          * packet_avail_size returns the available size in the current
 381          * packet. Note that the size returned is only a hint, since it
 382          * may change due to concurrent writes.
 383          */
 384         size_t (*packet_avail_size)(struct channel *chan,
 385                                     struct lttng_ust_shm_handle *handle);
 386         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 387         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 388         int (*is_finalized)(struct channel *chan);
 389         int (*is_disabled)(struct channel *chan);
 390         int (*flush_buffer)(struct channel *chan, struct lttng_ust_shm_handle *handle);
 391 };
 392
 393 /*
 394  * IMPORTANT: this structure is part of the ABI between the probe and
 395  * UST. Fields need to be only added at the end, never reordered, never
 396  * removed.
 397  */
 398 struct lttng_channel {
 399         /*
 400          * The pointers located in this private data are NOT safe to be
 401          * dereferenced by the consumer. The only operations the
 402          * consumer process is designed to be allowed to do is to read
 403          * and perform subbuffer flush.
 404          */
 405         struct channel *chan;           /* Channel buffers */
 406         int enabled;
 407         struct lttng_ctx *ctx;
 408         /* Event ID management */
 409         struct lttng_session *session;
 410         int objd;                       /* Object associated to channel */
 411         unsigned int free_event_id;     /* Next event ID to allocate */
 412         unsigned int used_event_id;     /* Max allocated event IDs */
 413         struct cds_list_head node;      /* Channel list in session */
 414         struct lttng_channel_ops *ops;
 415         int header_type;                /* 0: unset, 1: compact, 2: large */
 416         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
 417         unsigned int metadata_dumped:1;
 418
 419         /* Channel ID, available for consumer too */
 420         unsigned int id;
 421         /* Copy of session UUID for consumer (availability through shm) */
 422         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 423 };
 424
 425 #define LTTNG_UST_EVENT_HT_BITS         6
 426 #define LTTNG_UST_EVENT_HT_SIZE         (1U << LTTNG_UST_EVENT_HT_BITS)
 427
 428 struct lttng_ust_event_ht {
 429         struct cds_hlist_head table[LTTNG_UST_EVENT_HT_SIZE];
 430 };
 431
 432 /*
 433  * IMPORTANT: this structure is part of the ABI between the probe and
 434  * UST. Fields need to be only added at the end, never reordered, never
 435  * removed.
 436  */
 437 struct lttng_session {
 438         int active;                             /* Is trace session active ? */
 439         int been_active;                        /* Been active ? */
 440         int objd;                               /* Object associated */
 441         struct lttng_channel *metadata;         /* Metadata channel */
 442         struct cds_list_head chan_head;         /* Channel list head */
 443         struct cds_list_head events_head;       /* list of events */
 444         struct cds_list_head _deprecated1;
 445         struct cds_list_head node;              /* Session list */
 446         unsigned int free_chan_id;              /* Next chan ID to allocate */
 447         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 448         unsigned int metadata_dumped:1;
 449
 450         /* New UST 2.1 */
 451         /* List of enablers */
 452         struct cds_list_head enablers_head;
 453 };
 454
 455 struct lttng_transport {
 456         char *name;
 457         struct cds_list_head node;
 458         struct lttng_channel_ops ops;
 459 };
 460
 461 struct lttng_session *lttng_session_create(void);
 462 int lttng_session_enable(struct lttng_session *session);
 463 int lttng_session_disable(struct lttng_session *session);
 464 void lttng_session_destroy(struct lttng_session *session);
 465
 466 struct lttng_channel *lttng_channel_create(struct lttng_session *session,
 467                                        const char *transport_name,
 468                                        void *buf_addr,
 469                                        size_t subbuf_size, size_t num_subbuf,
 470                                        unsigned int switch_timer_interval,
 471                                        unsigned int read_timer_interval,
 472                                        int **shm_fd, int **wait_fd,
 473                                        uint64_t **memory_map_size,
 474                                        struct lttng_channel *chan_priv_init);
 475 struct lttng_channel *lttng_global_channel_create(struct lttng_session *session,
 476                                        int overwrite, void *buf_addr,
 477                                        size_t subbuf_size, size_t num_subbuf,
 478                                        unsigned int switch_timer_interval,
 479                                        unsigned int read_timer_interval,
 480                                        int **shm_fd, int **wait_fd,
 481                                        uint64_t **memory_map_size);
 482
 483 int lttng_channel_enable(struct lttng_channel *channel);
 484 int lttng_channel_disable(struct lttng_channel *channel);
 485
 486 struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type,
 487                 struct lttng_ust_event *event_param,
 488                 struct lttng_channel *chan);
 489 int lttng_enabler_enable(struct lttng_enabler *enabler);
 490 int lttng_enabler_disable(struct lttng_enabler *enabler);
 491 int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
 492                 struct lttng_ust_filter_bytecode_node *bytecode);
 493 int lttng_enabler_attach_context(struct lttng_enabler *enabler,
 494                 struct lttng_ust_context *ctx);
 495
 496 int lttng_attach_context(struct lttng_ust_context *context_param,
 497                 struct lttng_ctx **ctx, struct lttng_session *session);
 498
 499 void lttng_transport_register(struct lttng_transport *transport);
 500 void lttng_transport_unregister(struct lttng_transport *transport);
 501
 502 void synchronize_trace(void);
 503
 504 int lttng_probe_register(struct lttng_probe_desc *desc);
 505 void lttng_probe_unregister(struct lttng_probe_desc *desc);
 506 int lttng_fix_pending_event_desc(const struct lttng_event_desc *desc);
 507 const struct lttng_event_desc *lttng_event_get(const char *name);
 508 void lttng_event_put(const struct lttng_event_desc *desc);
 509 int lttng_probes_init(void);
 510 void lttng_probes_exit(void);
 511 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 512 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p);
 513 void lttng_remove_context_field(struct lttng_ctx **ctx_p,
 514                                 struct lttng_ctx_field *field);
 515 void lttng_destroy_context(struct lttng_ctx *ctx);
 516 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 517 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 518 int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
 519 int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
 520 void lttng_context_vtid_reset(void);
 521 void lttng_context_vpid_reset(void);
 522
 523 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
 524 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
 525 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;
 526
 527 struct lttng_transport *lttng_transport_find(const char *name);
 528
 529 int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
 530 void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
 531 struct lttng_ust_tracepoint_iter *
 532         lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
 533 int lttng_probes_get_field_list(struct lttng_ust_field_list *list);
 534 void lttng_probes_prune_field_list(struct lttng_ust_field_list *list);
 535 struct lttng_ust_field_iter *
 536         lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list);
 537
 538 void lttng_filter_event_link_bytecode(struct lttng_event *event);
 539 void lttng_enabler_event_link_bytecode(struct lttng_event *event,
 540                 struct lttng_enabler *enabler);
 541 void lttng_free_event_filter_runtime(struct lttng_event *event);
 542 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime);
 543
 544 struct cds_list_head *lttng_get_probe_list_head(void);
 545
 546 #endif /* _LTTNG_UST_EVENTS_H */