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 #define LTTNG_UST_CTX_FIELD_PADDING     40
 209 struct lttng_ctx_field {
 210         struct lttng_event_field event_field;
 211         size_t (*get_size)(size_t offset);
 212         void (*record)(struct lttng_ctx_field *field,
 213                        struct lttng_ust_lib_ring_buffer_ctx *ctx,
 214                        struct lttng_channel *chan);
 215         union {
 216                 char padding[LTTNG_UST_CTX_FIELD_PADDING];
 217         } u;
 218         void (*destroy)(struct lttng_ctx_field *field);
 219 };
 220
 221 #define LTTNG_UST_CTX_PADDING   24
 222 struct lttng_ctx {
 223         struct lttng_ctx_field *fields;
 224         unsigned int nr_fields;
 225         unsigned int allocated_fields;
 226         char padding[LTTNG_UST_CTX_PADDING];
 227 };
 228
 229 #define LTTNG_UST_EVENT_DESC_PADDING    40
 230 struct lttng_event_desc {
 231         const char *name;
 232         void (*probe_callback)(void);
 233         const struct lttng_event_ctx *ctx;      /* context */
 234         const struct lttng_event_field *fields; /* event payload */
 235         unsigned int nr_fields;
 236         const int **loglevel;
 237         const char *signature;  /* Argument types/names received */
 238         union {
 239                 struct {
 240                         const char **model_emf_uri;
 241                 } ext;
 242                 char padding[LTTNG_UST_EVENT_DESC_PADDING];
 243         } u;
 244 };
 245
 246 #define LTTNG_UST_PROBE_DESC_PADDING    20
 247 struct lttng_probe_desc {
 248         const char *provider;
 249         const struct lttng_event_desc **event_desc;
 250         unsigned int nr_events;
 251         struct cds_list_head head;              /* chain registered probes */
 252         struct cds_list_head lazy_init_head;
 253         int lazy;                               /* lazy registration */
 254         char padding[LTTNG_UST_PROBE_DESC_PADDING];
 255 };
 256
 257 /* Data structures used by the tracer. */
 258
 259 enum lttng_enabler_type {
 260         LTTNG_ENABLER_WILDCARD,
 261         LTTNG_ENABLER_EVENT,
 262 };
 263
 264 /*
 265  * Enabler field, within whatever object is enabling an event. Target of
 266  * backward reference.
 267  */
 268 struct lttng_enabler {
 269         enum lttng_enabler_type type;
 270
 271         /* head list of struct lttng_ust_filter_bytecode_node */
 272         struct cds_list_head filter_bytecode_head;
 273         struct cds_list_head node;      /* per-session list of enablers */
 274
 275         struct lttng_ust_event event_param;
 276         struct lttng_channel *chan;
 277         struct lttng_ctx *ctx;
 278         unsigned int enabled:1;
 279 };
 280
 281 struct tp_list_entry {
 282         struct lttng_ust_tracepoint_iter tp;
 283         struct cds_list_head head;
 284 };
 285
 286 struct lttng_ust_tracepoint_list {
 287         struct tp_list_entry *iter;
 288         struct cds_list_head head;
 289 };
 290
 291 struct tp_field_list_entry {
 292         struct lttng_ust_field_iter field;
 293         struct cds_list_head head;
 294 };
 295
 296 struct lttng_ust_field_list {
 297         struct tp_field_list_entry *iter;
 298         struct cds_list_head head;
 299 };
 300
 301 struct ust_pending_probe;
 302 struct lttng_event;
 303
 304 struct lttng_ust_filter_bytecode_node {
 305         struct cds_list_head node;
 306         struct lttng_enabler *enabler;
 307         /*
 308          * struct lttng_ust_filter_bytecode has var. sized array, must
 309          * be last field.
 310          */
 311         struct lttng_ust_filter_bytecode bc;
 312 };
 313
 314 /*
 315  * Filter return value masks.
 316  */
 317 enum lttng_filter_ret {
 318         LTTNG_FILTER_DISCARD = 0,
 319         LTTNG_FILTER_RECORD_FLAG = (1ULL << 0),
 320         /* Other bits are kept for future use. */
 321 };
 322
 323 struct lttng_bytecode_runtime {
 324         /* Associated bytecode */
 325         struct lttng_ust_filter_bytecode_node *bc;
 326         uint64_t (*filter)(void *filter_data, const char *filter_stack_data);
 327         int link_failed;
 328         struct cds_list_head node;      /* list of bytecode runtime in event */
 329 };
 330
 331 /*
 332  * Objects in a linked-list of enablers, owned by an event.
 333  */
 334 struct lttng_enabler_ref {
 335         struct cds_list_head node;              /* enabler ref list */
 336         struct lttng_enabler *ref;              /* backward ref */
 337 };
 338
 339 /*
 340  * lttng_event structure is referred to by the tracing fast path. It
 341  * must be kept small.
 342  *
 343  * IMPORTANT: this structure is part of the ABI between the probe and
 344  * UST. Fields need to be only added at the end, never reordered, never
 345  * removed.
 346  */
 347 struct lttng_event {
 348         /* LTTng-UST 2.0 starts here */
 349         unsigned int id;
 350         struct lttng_channel *chan;
 351         int enabled;
 352         const struct lttng_event_desc *desc;
 353         void *_deprecated1;
 354         struct lttng_ctx *ctx;
 355         enum lttng_ust_instrumentation instrumentation;
 356         union {
 357         } u;
 358         struct cds_list_head node;              /* Event list in session */
 359         struct cds_list_head _deprecated2;
 360         void *_deprecated3;
 361         unsigned int _deprecated4:1;
 362
 363         /* LTTng-UST 2.1 starts here */
 364         /* list of struct lttng_bytecode_runtime, sorted by seqnum */
 365         struct cds_list_head bytecode_runtime_head;
 366         int has_enablers_without_bytecode;
 367         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 368         struct cds_list_head enablers_ref_head;
 369         struct cds_hlist_node hlist;    /* session ht of events */
 370         int registered;                 /* has reg'd tracepoint probe */
 371 };
 372
 373 struct channel;
 374 struct lttng_ust_shm_handle;
 375
 376 /*
 377  * IMPORTANT: this structure is part of the ABI between the probe and
 378  * UST. Fields need to be only added at the end, never reordered, never
 379  * removed.
 380  */
 381 struct lttng_channel_ops {
 382         struct lttng_channel *(*channel_create)(const char *name,
 383                         void *buf_addr,
 384                         size_t subbuf_size, size_t num_subbuf,
 385                         unsigned int switch_timer_interval,
 386                         unsigned int read_timer_interval,
 387                         unsigned char *uuid,
 388                         uint32_t chan_id);
 389         void (*channel_destroy)(struct lttng_channel *chan);
 390         int (*event_reserve)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 391                              uint32_t event_id);
 392         void (*event_commit)(struct lttng_ust_lib_ring_buffer_ctx *ctx);
 393         void (*event_write)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 394                         const void *src, size_t len);
 395         /*
 396          * packet_avail_size returns the available size in the current
 397          * packet. Note that the size returned is only a hint, since it
 398          * may change due to concurrent writes.
 399          */
 400         size_t (*packet_avail_size)(struct channel *chan,
 401                                     struct lttng_ust_shm_handle *handle);
 402         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 403         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 404         int (*is_finalized)(struct channel *chan);
 405         int (*is_disabled)(struct channel *chan);
 406         int (*flush_buffer)(struct channel *chan, struct lttng_ust_shm_handle *handle);
 407 };
 408
 409 /*
 410  * IMPORTANT: this structure is part of the ABI between the probe and
 411  * UST. Fields need to be only added at the end, never reordered, never
 412  * removed.
 413  */
 414 struct lttng_channel {
 415         /*
 416          * The pointers located in this private data are NOT safe to be
 417          * dereferenced by the consumer. The only operations the
 418          * consumer process is designed to be allowed to do is to read
 419          * and perform subbuffer flush.
 420          */
 421         struct channel *chan;           /* Channel buffers */
 422         int enabled;
 423         struct lttng_ctx *ctx;
 424         /* Event ID management */
 425         struct lttng_session *session;
 426         int objd;                       /* Object associated to channel */
 427         unsigned int _deprecated1;
 428         unsigned int _deprecated2;
 429         struct cds_list_head node;      /* Channel list in session */
 430         const struct lttng_channel_ops *ops;
 431         int header_type;                /* 0: unset, 1: compact, 2: large */
 432         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
 433         unsigned int _deprecated3:1;
 434
 435         /* Channel ID */
 436         unsigned int id;
 437         enum lttng_ust_chan_type type;
 438         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 439         int tstate:1;                   /* Transient enable state */
 440 };
 441
 442 #define LTTNG_UST_EVENT_HT_BITS         12
 443 #define LTTNG_UST_EVENT_HT_SIZE         (1U << LTTNG_UST_EVENT_HT_BITS)
 444
 445 struct lttng_ust_event_ht {
 446         struct cds_hlist_head table[LTTNG_UST_EVENT_HT_SIZE];
 447 };
 448
 449 /*
 450  * IMPORTANT: this structure is part of the ABI between the probe and
 451  * UST. Fields need to be only added at the end, never reordered, never
 452  * removed.
 453  */
 454 struct lttng_session {
 455         int active;                             /* Is trace session active ? */
 456         int been_active;                        /* Been active ? */
 457         int objd;                               /* Object associated */
 458         void *_deprecated1;
 459         struct cds_list_head chan_head;         /* Channel list head */
 460         struct cds_list_head events_head;       /* list of events */
 461         struct cds_list_head _deprecated2;
 462         struct cds_list_head node;              /* Session list */
 463         int _deprecated3;
 464         unsigned int _deprecated4:1;
 465
 466         /* New UST 2.1 */
 467         /* List of enablers */
 468         struct cds_list_head enablers_head;
 469         struct lttng_ust_event_ht events_ht;    /* ht of events */
 470         void *owner;                            /* object owner */
 471         int tstate:1;                           /* Transient enable state */
 472 };
 473
 474 struct lttng_transport {
 475         char *name;
 476         struct cds_list_head node;
 477         struct lttng_channel_ops ops;
 478         const struct lttng_ust_lib_ring_buffer_config *client_config;
 479 };
 480
 481 struct lttng_session *lttng_session_create(void);
 482 int lttng_session_enable(struct lttng_session *session);
 483 int lttng_session_disable(struct lttng_session *session);
 484 void lttng_session_destroy(struct lttng_session *session);
 485
 486 struct lttng_channel *lttng_channel_create(struct lttng_session *session,
 487                                        const char *transport_name,
 488                                        void *buf_addr,
 489                                        size_t subbuf_size, size_t num_subbuf,
 490                                        unsigned int switch_timer_interval,
 491                                        unsigned int read_timer_interval,
 492                                        int **shm_fd, int **wait_fd,
 493                                        uint64_t **memory_map_size,
 494                                        struct lttng_channel *chan_priv_init);
 495
 496 int lttng_channel_enable(struct lttng_channel *channel);
 497 int lttng_channel_disable(struct lttng_channel *channel);
 498
 499 struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type,
 500                 struct lttng_ust_event *event_param,
 501                 struct lttng_channel *chan);
 502 int lttng_enabler_enable(struct lttng_enabler *enabler);
 503 int lttng_enabler_disable(struct lttng_enabler *enabler);
 504 int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
 505                 struct lttng_ust_filter_bytecode_node *bytecode);
 506 int lttng_enabler_attach_context(struct lttng_enabler *enabler,
 507                 struct lttng_ust_context *ctx);
 508
 509 int lttng_attach_context(struct lttng_ust_context *context_param,
 510                 struct lttng_ctx **ctx, struct lttng_session *session);
 511
 512 void lttng_transport_register(struct lttng_transport *transport);
 513 void lttng_transport_unregister(struct lttng_transport *transport);
 514
 515 void synchronize_trace(void);
 516
 517 int lttng_probe_register(struct lttng_probe_desc *desc);
 518 void lttng_probe_unregister(struct lttng_probe_desc *desc);
 519 int lttng_fix_pending_event_desc(const struct lttng_event_desc *desc);
 520 int lttng_probes_init(void);
 521 void lttng_probes_exit(void);
 522 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 523 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p);
 524 void lttng_remove_context_field(struct lttng_ctx **ctx_p,
 525                                 struct lttng_ctx_field *field);
 526 void lttng_destroy_context(struct lttng_ctx *ctx);
 527 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 528 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 529 int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
 530 int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
 531 void lttng_context_vtid_reset(void);
 532 void lttng_context_vpid_reset(void);
 533
 534 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
 535 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
 536 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;
 537
 538 struct lttng_transport *lttng_transport_find(const char *name);
 539
 540 int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
 541 void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
 542 struct lttng_ust_tracepoint_iter *
 543         lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
 544 int lttng_probes_get_field_list(struct lttng_ust_field_list *list);
 545 void lttng_probes_prune_field_list(struct lttng_ust_field_list *list);
 546 struct lttng_ust_field_iter *
 547         lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list);
 548
 549 void lttng_filter_event_link_bytecode(struct lttng_event *event);
 550 void lttng_enabler_event_link_bytecode(struct lttng_event *event,
 551                 struct lttng_enabler *enabler);
 552 void lttng_free_event_filter_runtime(struct lttng_event *event);
 553 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime);
 554
 555 struct cds_list_head *lttng_get_probe_list_head(void);
 556 int lttng_session_active(void);
 557
 558 #endif /* _LTTNG_UST_EVENTS_H */