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 /*
 303  * Filter return value masks.
 304  */
 305 enum lttng_filter_ret {
 306         LTTNG_FILTER_DISCARD = 0,
 307         LTTNG_FILTER_RECORD_FLAG = (1ULL << 0),
 308         /* Other bits are kept for future use. */
 309 };
 310
 311 struct lttng_bytecode_runtime {
 312         /* Associated bytecode */
 313         struct lttng_ust_filter_bytecode_node *bc;
 314         uint64_t (*filter)(void *filter_data, const char *filter_stack_data);
 315         int link_failed;
 316         struct cds_list_head node;      /* list of bytecode runtime in event */
 317 };
 318
 319 /*
 320  * Objects in a linked-list of enablers, owned by an event.
 321  */
 322 struct lttng_enabler_ref {
 323         struct cds_list_head node;              /* enabler ref list */
 324         struct lttng_enabler *ref;              /* backward ref */
 325 };
 326
 327 /*
 328  * lttng_event structure is referred to by the tracing fast path. It
 329  * must be kept small.
 330  *
 331  * IMPORTANT: this structure is part of the ABI between the probe and
 332  * UST. Fields need to be only added at the end, never reordered, never
 333  * removed.
 334  */
 335 struct lttng_event {
 336         /* LTTng-UST 2.0 starts here */
 337         unsigned int id;
 338         struct lttng_channel *chan;
 339         int enabled;
 340         const struct lttng_event_desc *desc;
 341         void *_deprecated1;
 342         struct lttng_ctx *ctx;
 343         enum lttng_ust_instrumentation instrumentation;
 344         union {
 345         } u;
 346         struct cds_list_head node;              /* Event list in session */
 347         struct cds_list_head _deprecated2;
 348         void *_deprecated3;
 349         unsigned int metadata_dumped:1;
 350
 351         /* LTTng-UST 2.1 starts here */
 352         /* list of struct lttng_bytecode_runtime, sorted by seqnum */
 353         struct cds_list_head bytecode_runtime_head;
 354
 355         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 356         struct cds_list_head enablers_ref_head;
 357 };
 358
 359 struct channel;
 360 struct lttng_ust_shm_handle;
 361
 362 /*
 363  * IMPORTANT: this structure is part of the ABI between the probe and
 364  * UST. Fields need to be only added at the end, never reordered, never
 365  * removed.
 366  */
 367 struct lttng_channel_ops {
 368         struct lttng_channel *(*channel_create)(const char *name,
 369                                 void *buf_addr,
 370                                 size_t subbuf_size, size_t num_subbuf,
 371                                 unsigned int switch_timer_interval,
 372                                 unsigned int read_timer_interval,
 373                                 int **shm_fd, int **wait_fd,
 374                                 uint64_t **memory_map_size,
 375                                 struct lttng_channel *chan_priv_init);
 376         void (*channel_destroy)(struct lttng_channel *lttng_chan);
 377         struct lttng_ust_lib_ring_buffer *(*buffer_read_open)(struct channel *chan,
 378                                 struct lttng_ust_shm_handle *handle,
 379                                 int **shm_fd, int **wait_fd,
 380                                 uint64_t **memory_map_size);
 381         void (*buffer_read_close)(struct lttng_ust_lib_ring_buffer *buf,
 382                                 struct lttng_ust_shm_handle *handle);
 383         int (*event_reserve)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 384                              uint32_t event_id);
 385         void (*event_commit)(struct lttng_ust_lib_ring_buffer_ctx *ctx);
 386         void (*event_write)(struct lttng_ust_lib_ring_buffer_ctx *ctx, const void *src,
 387                             size_t len);
 388         /*
 389          * packet_avail_size returns the available size in the current
 390          * packet. Note that the size returned is only a hint, since it
 391          * may change due to concurrent writes.
 392          */
 393         size_t (*packet_avail_size)(struct channel *chan,
 394                                     struct lttng_ust_shm_handle *handle);
 395         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 396         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 397         int (*is_finalized)(struct channel *chan);
 398         int (*is_disabled)(struct channel *chan);
 399         int (*flush_buffer)(struct channel *chan, struct lttng_ust_shm_handle *handle);
 400 };
 401
 402 /*
 403  * IMPORTANT: this structure is part of the ABI between the probe and
 404  * UST. Fields need to be only added at the end, never reordered, never
 405  * removed.
 406  */
 407 struct lttng_channel {
 408         /*
 409          * The pointers located in this private data are NOT safe to be
 410          * dereferenced by the consumer. The only operations the
 411          * consumer process is designed to be allowed to do is to read
 412          * and perform subbuffer flush.
 413          */
 414         struct channel *chan;           /* Channel buffers */
 415         int enabled;
 416         struct lttng_ctx *ctx;
 417         /* Event ID management */
 418         struct lttng_session *session;
 419         int objd;                       /* Object associated to channel */
 420         unsigned int free_event_id;     /* Next event ID to allocate */
 421         unsigned int used_event_id;     /* Max allocated event IDs */
 422         struct cds_list_head node;      /* Channel list in session */
 423         struct lttng_channel_ops *ops;
 424         int header_type;                /* 0: unset, 1: compact, 2: large */
 425         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
 426         unsigned int metadata_dumped:1;
 427
 428         /* Channel ID, available for consumer too */
 429         unsigned int id;
 430         /* Copy of session UUID for consumer (availability through shm) */
 431         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 432 };
 433
 434 #define LTTNG_UST_EVENT_HT_BITS         6
 435 #define LTTNG_UST_EVENT_HT_SIZE         (1U << LTTNG_UST_EVENT_HT_BITS)
 436
 437 struct lttng_ust_event_ht {
 438         struct cds_hlist_head table[LTTNG_UST_EVENT_HT_SIZE];
 439 };
 440
 441 /*
 442  * IMPORTANT: this structure is part of the ABI between the probe and
 443  * UST. Fields need to be only added at the end, never reordered, never
 444  * removed.
 445  */
 446 struct lttng_session {
 447         int active;                             /* Is trace session active ? */
 448         int been_active;                        /* Been active ? */
 449         int objd;                               /* Object associated */
 450         struct lttng_channel *metadata;         /* Metadata channel */
 451         struct cds_list_head chan_head;         /* Channel list head */
 452         struct cds_list_head events_head;       /* list of events */
 453         struct cds_list_head _deprecated1;
 454         struct cds_list_head node;              /* Session list */
 455         unsigned int free_chan_id;              /* Next chan ID to allocate */
 456         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 457         unsigned int metadata_dumped:1;
 458
 459         /* New UST 2.1 */
 460         /* List of enablers */
 461         struct cds_list_head enablers_head;
 462 };
 463
 464 struct lttng_transport {
 465         char *name;
 466         struct cds_list_head node;
 467         struct lttng_channel_ops ops;
 468 };
 469
 470 struct lttng_session *lttng_session_create(void);
 471 int lttng_session_enable(struct lttng_session *session);
 472 int lttng_session_disable(struct lttng_session *session);
 473 void lttng_session_destroy(struct lttng_session *session);
 474
 475 struct lttng_channel *lttng_channel_create(struct lttng_session *session,
 476                                        const char *transport_name,
 477                                        void *buf_addr,
 478                                        size_t subbuf_size, size_t num_subbuf,
 479                                        unsigned int switch_timer_interval,
 480                                        unsigned int read_timer_interval,
 481                                        int **shm_fd, int **wait_fd,
 482                                        uint64_t **memory_map_size,
 483                                        struct lttng_channel *chan_priv_init);
 484 struct lttng_channel *lttng_global_channel_create(struct lttng_session *session,
 485                                        int overwrite, void *buf_addr,
 486                                        size_t subbuf_size, size_t num_subbuf,
 487                                        unsigned int switch_timer_interval,
 488                                        unsigned int read_timer_interval,
 489                                        int **shm_fd, int **wait_fd,
 490                                        uint64_t **memory_map_size);
 491
 492 int lttng_channel_enable(struct lttng_channel *channel);
 493 int lttng_channel_disable(struct lttng_channel *channel);
 494
 495 struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type,
 496                 struct lttng_ust_event *event_param,
 497                 struct lttng_channel *chan);
 498 int lttng_enabler_enable(struct lttng_enabler *enabler);
 499 int lttng_enabler_disable(struct lttng_enabler *enabler);
 500 int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
 501                 struct lttng_ust_filter_bytecode_node *bytecode);
 502 int lttng_enabler_attach_context(struct lttng_enabler *enabler,
 503                 struct lttng_ust_context *ctx);
 504
 505 int lttng_attach_context(struct lttng_ust_context *context_param,
 506                 struct lttng_ctx **ctx, struct lttng_session *session);
 507
 508 void lttng_transport_register(struct lttng_transport *transport);
 509 void lttng_transport_unregister(struct lttng_transport *transport);
 510
 511 void synchronize_trace(void);
 512
 513 int lttng_probe_register(struct lttng_probe_desc *desc);
 514 void lttng_probe_unregister(struct lttng_probe_desc *desc);
 515 int lttng_fix_pending_event_desc(const struct lttng_event_desc *desc);
 516 const struct lttng_event_desc *lttng_event_get(const char *name);
 517 void lttng_event_put(const struct lttng_event_desc *desc);
 518 int lttng_probes_init(void);
 519 void lttng_probes_exit(void);
 520 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 521 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p);
 522 void lttng_remove_context_field(struct lttng_ctx **ctx_p,
 523                                 struct lttng_ctx_field *field);
 524 void lttng_destroy_context(struct lttng_ctx *ctx);
 525 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 526 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 527 int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
 528 int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
 529 void lttng_context_vtid_reset(void);
 530 void lttng_context_vpid_reset(void);
 531
 532 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
 533 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
 534 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;
 535
 536 struct lttng_transport *lttng_transport_find(const char *name);
 537
 538 int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
 539 void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
 540 struct lttng_ust_tracepoint_iter *
 541         lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
 542 int lttng_probes_get_field_list(struct lttng_ust_field_list *list);
 543 void lttng_probes_prune_field_list(struct lttng_ust_field_list *list);
 544 struct lttng_ust_field_iter *
 545         lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list);
 546
 547 void lttng_filter_event_link_bytecode(struct lttng_event *event);
 548 void lttng_enabler_event_link_bytecode(struct lttng_event *event,
 549                 struct lttng_enabler *enabler);
 550 void lttng_free_event_filter_runtime(struct lttng_event *event);
 551 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime);
 552
 553 struct cds_list_head *lttng_get_probe_list_head(void);
 554
 555 #endif /* _LTTNG_UST_EVENTS_H */