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 #ifdef __cplusplus
  39 extern "C" {
  40 #endif
  41
  42 #define LTTNG_UST_UUID_LEN              16
  43
  44 /*
  45  * Tracepoint provider version. Compatibility based on the major number.
  46  * Older tracepoint providers can always register to newer lttng-ust
  47  * library, but the opposite is rejected: a newer tracepoint provider is
  48  * rejected by an older lttng-ust library.
  49  */
  50 #define LTTNG_UST_PROVIDER_MAJOR        1
  51 #define LTTNG_UST_PROVIDER_MINOR        0
  52
  53 struct lttng_channel;
  54 struct lttng_session;
  55 struct lttng_ust_lib_ring_buffer_ctx;
  56
  57 /*
  58  * Data structures used by tracepoint event declarations, and by the
  59  * tracer. Those structures have padding for future extension.
  60  */
  61
  62 /*
  63  * LTTng client type enumeration. Used by the consumer to map the
  64  * callbacks from its own address space.
  65  */
  66 enum lttng_client_types {
  67         LTTNG_CLIENT_METADATA = 0,
  68         LTTNG_CLIENT_DISCARD = 1,
  69         LTTNG_CLIENT_OVERWRITE = 2,
  70         LTTNG_CLIENT_DISCARD_RT = 3,
  71         LTTNG_CLIENT_OVERWRITE_RT = 4,
  72         LTTNG_NR_CLIENT_TYPES,
  73 };
  74
  75 /* Type description */
  76
  77 /* Update the astract_types name table in lttng-types.c along with this enum */
  78 enum lttng_abstract_types {
  79         atype_integer,
  80         atype_enum,
  81         atype_array,
  82         atype_sequence,
  83         atype_string,
  84         atype_float,
  85         NR_ABSTRACT_TYPES,
  86 };
  87
  88 /* Update the string_encodings name table in lttng-types.c along with this enum */
  89 enum lttng_string_encodings {
  90         lttng_encode_none = 0,
  91         lttng_encode_UTF8 = 1,
  92         lttng_encode_ASCII = 2,
  93         NR_STRING_ENCODINGS,
  94 };
  95
  96 #define LTTNG_UST_ENUM_ENTRY_PADDING    16
  97 struct lttng_enum_entry {
  98         unsigned long long start, end;  /* start and end are inclusive */
  99         const char *string;
 100         char padding[LTTNG_UST_ENUM_ENTRY_PADDING];
 101 };
 102
 103 #define __type_integer(_type, _byte_order, _base, _encoding)    \
 104         {                                                       \
 105             .atype = atype_integer,                             \
 106             .u.basic.integer =                                  \
 107                 {                                               \
 108                   .size = sizeof(_type) * CHAR_BIT,             \
 109                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
 110                   .signedness = lttng_is_signed_type(_type),    \
 111                   .reverse_byte_order = _byte_order != BYTE_ORDER,      \
 112                   .base = _base,                                \
 113                   .encoding = lttng_encode_##_encoding,         \
 114                 },                                              \
 115         }                                                       \
 116
 117 #define LTTNG_UST_INTEGER_TYPE_PADDING  24
 118 struct lttng_integer_type {
 119         unsigned int size;              /* in bits */
 120         unsigned short alignment;       /* in bits */
 121         unsigned int signedness:1;
 122         unsigned int reverse_byte_order:1;
 123         unsigned int base;              /* 2, 8, 10, 16, for pretty print */
 124         enum lttng_string_encodings encoding;
 125         char padding[LTTNG_UST_INTEGER_TYPE_PADDING];
 126 };
 127
 128 /*
 129  * Only float and double are supported. long double is not supported at
 130  * the moment.
 131  */
 132 #define _float_mant_dig(_type)                                          \
 133         (sizeof(_type) == sizeof(float) ? FLT_MANT_DIG                  \
 134                 : (sizeof(_type) == sizeof(double) ? DBL_MANT_DIG       \
 135                 : 0))
 136
 137 #define __type_float(_type)                                     \
 138         {                                                       \
 139             .atype = atype_float,                               \
 140             .u.basic._float =                                   \
 141                 {                                               \
 142                   .exp_dig = sizeof(_type) * CHAR_BIT           \
 143                                 - _float_mant_dig(_type),       \
 144                   .mant_dig = _float_mant_dig(_type),           \
 145                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
 146                   .reverse_byte_order = BYTE_ORDER != FLOAT_WORD_ORDER, \
 147                 },                                              \
 148         }                                                       \
 149
 150 #define LTTNG_UST_FLOAT_TYPE_PADDING    24
 151 struct lttng_float_type {
 152         unsigned int exp_dig;           /* exponent digits, in bits */
 153         unsigned int mant_dig;          /* mantissa digits, in bits */
 154         unsigned short alignment;       /* in bits */
 155         unsigned int reverse_byte_order:1;
 156         char padding[LTTNG_UST_FLOAT_TYPE_PADDING];
 157 };
 158
 159 #define LTTNG_UST_BASIC_TYPE_PADDING    128
 160 union _lttng_basic_type {
 161         struct lttng_integer_type integer;
 162         struct {
 163                 const char *name;
 164         } enumeration;
 165         struct {
 166                 enum lttng_string_encodings encoding;
 167         } string;
 168         struct lttng_float_type _float;
 169         char padding[LTTNG_UST_BASIC_TYPE_PADDING];
 170 };
 171
 172 struct lttng_basic_type {
 173         enum lttng_abstract_types atype;
 174         union {
 175                 union _lttng_basic_type basic;
 176         } u;
 177 };
 178
 179 #define LTTNG_UST_TYPE_PADDING  128
 180 struct lttng_type {
 181         enum lttng_abstract_types atype;
 182         union {
 183                 union _lttng_basic_type basic;
 184                 struct {
 185                         struct lttng_basic_type elem_type;
 186                         unsigned int length;            /* num. elems. */
 187                 } array;
 188                 struct {
 189                         struct lttng_basic_type length_type;
 190                         struct lttng_basic_type elem_type;
 191                 } sequence;
 192                 char padding[LTTNG_UST_TYPE_PADDING];
 193         } u;
 194 };
 195
 196 #define LTTNG_UST_ENUM_TYPE_PADDING     24
 197 struct lttng_enum {
 198         const char *name;
 199         struct lttng_type container_type;
 200         const struct lttng_enum_entry *entries;
 201         unsigned int len;
 202         char padding[LTTNG_UST_ENUM_TYPE_PADDING];
 203 };
 204
 205 /*
 206  * Event field description
 207  *
 208  * IMPORTANT: this structure is part of the ABI between the probe and
 209  * UST. Fields need to be only added at the end, never reordered, never
 210  * removed.
 211  */
 212
 213 #define LTTNG_UST_EVENT_FIELD_PADDING   28
 214 struct lttng_event_field {
 215         const char *name;
 216         struct lttng_type type;
 217         unsigned int nowrite;   /* do not write into trace */
 218         char padding[LTTNG_UST_EVENT_FIELD_PADDING];
 219 };
 220
 221 union lttng_ctx_value {
 222         int64_t s64;
 223         const char *str;
 224         double d;
 225 };
 226
 227 #define LTTNG_UST_CTX_FIELD_PADDING     40
 228 struct lttng_ctx_field {
 229         struct lttng_event_field event_field;
 230         size_t (*get_size)(size_t offset);
 231         void (*record)(struct lttng_ctx_field *field,
 232                        struct lttng_ust_lib_ring_buffer_ctx *ctx,
 233                        struct lttng_channel *chan);
 234         void (*get_value)(struct lttng_ctx_field *field,
 235                          union lttng_ctx_value *value);
 236         union {
 237                 char padding[LTTNG_UST_CTX_FIELD_PADDING];
 238         } u;
 239         void (*destroy)(struct lttng_ctx_field *field);
 240 };
 241
 242 #define LTTNG_UST_CTX_PADDING   24
 243 struct lttng_ctx {
 244         struct lttng_ctx_field *fields;
 245         unsigned int nr_fields;
 246         unsigned int allocated_fields;
 247         char padding[LTTNG_UST_CTX_PADDING];
 248 };
 249
 250 #define LTTNG_UST_EVENT_DESC_PADDING    40
 251 struct lttng_event_desc {
 252         const char *name;
 253         void (*probe_callback)(void);
 254         const struct lttng_event_ctx *ctx;      /* context */
 255         const struct lttng_event_field *fields; /* event payload */
 256         unsigned int nr_fields;
 257         const int **loglevel;
 258         const char *signature;  /* Argument types/names received */
 259         union {
 260                 struct {
 261                         const char **model_emf_uri;
 262                 } ext;
 263                 char padding[LTTNG_UST_EVENT_DESC_PADDING];
 264         } u;
 265 };
 266
 267 #define LTTNG_UST_PROBE_DESC_PADDING    12
 268 struct lttng_probe_desc {
 269         const char *provider;
 270         const struct lttng_event_desc **event_desc;
 271         unsigned int nr_events;
 272         struct cds_list_head head;              /* chain registered probes */
 273         struct cds_list_head lazy_init_head;
 274         int lazy;                               /* lazy registration */
 275         uint32_t major;
 276         uint32_t minor;
 277         char padding[LTTNG_UST_PROBE_DESC_PADDING];
 278 };
 279
 280 /* Data structures used by the tracer. */
 281
 282 enum lttng_enabler_type {
 283         LTTNG_ENABLER_WILDCARD,
 284         LTTNG_ENABLER_EVENT,
 285 };
 286
 287 /*
 288  * Enabler field, within whatever object is enabling an event. Target of
 289  * backward reference.
 290  */
 291 struct lttng_enabler {
 292         enum lttng_enabler_type type;
 293
 294         /* head list of struct lttng_ust_filter_bytecode_node */
 295         struct cds_list_head filter_bytecode_head;
 296         struct cds_list_head node;      /* per-session list of enablers */
 297
 298         struct lttng_ust_event event_param;
 299         struct lttng_channel *chan;
 300         struct lttng_ctx *ctx;
 301         unsigned int enabled:1;
 302 };
 303
 304 struct tp_list_entry {
 305         struct lttng_ust_tracepoint_iter tp;
 306         struct cds_list_head head;
 307 };
 308
 309 struct lttng_ust_tracepoint_list {
 310         struct tp_list_entry *iter;
 311         struct cds_list_head head;
 312 };
 313
 314 struct tp_field_list_entry {
 315         struct lttng_ust_field_iter field;
 316         struct cds_list_head head;
 317 };
 318
 319 struct lttng_ust_field_list {
 320         struct tp_field_list_entry *iter;
 321         struct cds_list_head head;
 322 };
 323
 324 struct ust_pending_probe;
 325 struct lttng_event;
 326
 327 struct lttng_ust_filter_bytecode_node {
 328         struct cds_list_head node;
 329         struct lttng_enabler *enabler;
 330         /*
 331          * struct lttng_ust_filter_bytecode has var. sized array, must
 332          * be last field.
 333          */
 334         struct lttng_ust_filter_bytecode bc;
 335 };
 336
 337 /*
 338  * Filter return value masks.
 339  */
 340 enum lttng_filter_ret {
 341         LTTNG_FILTER_DISCARD = 0,
 342         LTTNG_FILTER_RECORD_FLAG = (1ULL << 0),
 343         /* Other bits are kept for future use. */
 344 };
 345
 346 struct lttng_bytecode_runtime {
 347         /* Associated bytecode */
 348         struct lttng_ust_filter_bytecode_node *bc;
 349         uint64_t (*filter)(void *filter_data, const char *filter_stack_data);
 350         int link_failed;
 351         struct cds_list_head node;      /* list of bytecode runtime in event */
 352 };
 353
 354 /*
 355  * Objects in a linked-list of enablers, owned by an event.
 356  */
 357 struct lttng_enabler_ref {
 358         struct cds_list_head node;              /* enabler ref list */
 359         struct lttng_enabler *ref;              /* backward ref */
 360 };
 361
 362 /*
 363  * lttng_event structure is referred to by the tracing fast path. It
 364  * must be kept small.
 365  *
 366  * IMPORTANT: this structure is part of the ABI between the probe and
 367  * UST. Fields need to be only added at the end, never reordered, never
 368  * removed.
 369  */
 370 struct lttng_event {
 371         /* LTTng-UST 2.0 starts here */
 372         unsigned int id;
 373         struct lttng_channel *chan;
 374         int enabled;
 375         const struct lttng_event_desc *desc;
 376         void *_deprecated1;
 377         struct lttng_ctx *ctx;
 378         enum lttng_ust_instrumentation instrumentation;
 379         union {
 380         } u;
 381         struct cds_list_head node;              /* Event list in session */
 382         struct cds_list_head _deprecated2;
 383         void *_deprecated3;
 384         unsigned int _deprecated4:1;
 385
 386         /* LTTng-UST 2.1 starts here */
 387         /* list of struct lttng_bytecode_runtime, sorted by seqnum */
 388         struct cds_list_head bytecode_runtime_head;
 389         int has_enablers_without_bytecode;
 390         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 391         struct cds_list_head enablers_ref_head;
 392         struct cds_hlist_node hlist;    /* session ht of events */
 393         int registered;                 /* has reg'd tracepoint probe */
 394 };
 395
 396 struct channel;
 397 struct lttng_ust_shm_handle;
 398
 399 /*
 400  * IMPORTANT: this structure is part of the ABI between the probe and
 401  * UST. Fields need to be only added at the end, never reordered, never
 402  * removed.
 403  */
 404 struct lttng_channel_ops {
 405         struct lttng_channel *(*channel_create)(const char *name,
 406                         void *buf_addr,
 407                         size_t subbuf_size, size_t num_subbuf,
 408                         unsigned int switch_timer_interval,
 409                         unsigned int read_timer_interval,
 410                         unsigned char *uuid,
 411                         uint32_t chan_id);
 412         void (*channel_destroy)(struct lttng_channel *chan);
 413         void *_deprecated1;
 414         void *_deprecated2;
 415         int (*event_reserve)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 416                              uint32_t event_id);
 417         void (*event_commit)(struct lttng_ust_lib_ring_buffer_ctx *ctx);
 418         void (*event_write)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 419                         const void *src, size_t len);
 420         /*
 421          * packet_avail_size returns the available size in the current
 422          * packet. Note that the size returned is only a hint, since it
 423          * may change due to concurrent writes.
 424          */
 425         size_t (*packet_avail_size)(struct channel *chan,
 426                                     struct lttng_ust_shm_handle *handle);
 427         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 428         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 429         int (*is_finalized)(struct channel *chan);
 430         int (*is_disabled)(struct channel *chan);
 431         int (*flush_buffer)(struct channel *chan, struct lttng_ust_shm_handle *handle);
 432 };
 433
 434 /*
 435  * IMPORTANT: this structure is part of the ABI between the probe and
 436  * UST. Fields need to be only added at the end, never reordered, never
 437  * removed.
 438  */
 439 struct lttng_channel {
 440         /*
 441          * The pointers located in this private data are NOT safe to be
 442          * dereferenced by the consumer. The only operations the
 443          * consumer process is designed to be allowed to do is to read
 444          * and perform subbuffer flush.
 445          */
 446         struct channel *chan;           /* Channel buffers */
 447         int enabled;
 448         struct lttng_ctx *ctx;
 449         /* Event ID management */
 450         struct lttng_session *session;
 451         int objd;                       /* Object associated to channel */
 452         unsigned int _deprecated1;
 453         unsigned int _deprecated2;
 454         struct cds_list_head node;      /* Channel list in session */
 455         const struct lttng_channel_ops *ops;
 456         int header_type;                /* 0: unset, 1: compact, 2: large */
 457         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
 458         unsigned int _deprecated3:1;
 459
 460         /* Channel ID */
 461         unsigned int id;
 462         enum lttng_ust_chan_type type;
 463         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 464         int tstate:1;                   /* Transient enable state */
 465 };
 466
 467 #define LTTNG_UST_EVENT_HT_BITS         12
 468 #define LTTNG_UST_EVENT_HT_SIZE         (1U << LTTNG_UST_EVENT_HT_BITS)
 469
 470 struct lttng_ust_event_ht {
 471         struct cds_hlist_head table[LTTNG_UST_EVENT_HT_SIZE];
 472 };
 473
 474 /*
 475  * IMPORTANT: this structure is part of the ABI between the probe and
 476  * UST. Fields need to be only added at the end, never reordered, never
 477  * removed.
 478  */
 479 struct lttng_session {
 480         int active;                             /* Is trace session active ? */
 481         int been_active;                        /* Been active ? */
 482         int objd;                               /* Object associated */
 483         void *_deprecated1;
 484         struct cds_list_head chan_head;         /* Channel list head */
 485         struct cds_list_head events_head;       /* list of events */
 486         struct cds_list_head _deprecated2;
 487         struct cds_list_head node;              /* Session list */
 488         int _deprecated3;
 489         unsigned int _deprecated4:1;
 490
 491         /* New UST 2.1 */
 492         /* List of enablers */
 493         struct cds_list_head enablers_head;
 494         struct lttng_ust_event_ht events_ht;    /* ht of events */
 495         void *owner;                            /* object owner */
 496         int tstate:1;                           /* Transient enable state */
 497 };
 498
 499 struct lttng_transport {
 500         char *name;
 501         struct cds_list_head node;
 502         struct lttng_channel_ops ops;
 503         const struct lttng_ust_lib_ring_buffer_config *client_config;
 504 };
 505
 506 struct lttng_session *lttng_session_create(void);
 507 int lttng_session_enable(struct lttng_session *session);
 508 int lttng_session_disable(struct lttng_session *session);
 509 void lttng_session_destroy(struct lttng_session *session);
 510
 511 struct lttng_channel *lttng_channel_create(struct lttng_session *session,
 512                                        const char *transport_name,
 513                                        void *buf_addr,
 514                                        size_t subbuf_size, size_t num_subbuf,
 515                                        unsigned int switch_timer_interval,
 516                                        unsigned int read_timer_interval,
 517                                        int **shm_fd, int **wait_fd,
 518                                        uint64_t **memory_map_size,
 519                                        struct lttng_channel *chan_priv_init);
 520
 521 int lttng_channel_enable(struct lttng_channel *channel);
 522 int lttng_channel_disable(struct lttng_channel *channel);
 523
 524 struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type,
 525                 struct lttng_ust_event *event_param,
 526                 struct lttng_channel *chan);
 527 int lttng_enabler_enable(struct lttng_enabler *enabler);
 528 int lttng_enabler_disable(struct lttng_enabler *enabler);
 529 int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
 530                 struct lttng_ust_filter_bytecode_node *bytecode);
 531 int lttng_enabler_attach_context(struct lttng_enabler *enabler,
 532                 struct lttng_ust_context *ctx);
 533
 534 int lttng_attach_context(struct lttng_ust_context *context_param,
 535                 struct lttng_ctx **ctx, struct lttng_session *session);
 536 void lttng_context_init(void);
 537 void lttng_context_exit(void);
 538 extern struct lttng_ctx *lttng_static_ctx;      /* Used by filtering */
 539
 540 void lttng_transport_register(struct lttng_transport *transport);
 541 void lttng_transport_unregister(struct lttng_transport *transport);
 542
 543 void synchronize_trace(void);
 544
 545 int lttng_probe_register(struct lttng_probe_desc *desc);
 546 void lttng_probe_unregister(struct lttng_probe_desc *desc);
 547 int lttng_fix_pending_events(void);
 548 int lttng_probes_init(void);
 549 void lttng_probes_exit(void);
 550 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 551 int lttng_get_context_index(struct lttng_ctx *ctx, const char *name);
 552 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p);
 553 void lttng_remove_context_field(struct lttng_ctx **ctx_p,
 554                                 struct lttng_ctx_field *field);
 555 void lttng_destroy_context(struct lttng_ctx *ctx);
 556 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 557 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 558 int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
 559 int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
 560 void lttng_context_vtid_reset(void);
 561 void lttng_context_vpid_reset(void);
 562
 563 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
 564 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
 565 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;
 566
 567 struct lttng_transport *lttng_transport_find(const char *name);
 568
 569 int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
 570 void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
 571 struct lttng_ust_tracepoint_iter *
 572         lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
 573 int lttng_probes_get_field_list(struct lttng_ust_field_list *list);
 574 void lttng_probes_prune_field_list(struct lttng_ust_field_list *list);
 575 struct lttng_ust_field_iter *
 576         lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list);
 577
 578 void lttng_filter_event_link_bytecode(struct lttng_event *event);
 579 void lttng_enabler_event_link_bytecode(struct lttng_event *event,
 580                 struct lttng_enabler *enabler);
 581 void lttng_free_event_filter_runtime(struct lttng_event *event);
 582 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime);
 583
 584 struct cds_list_head *lttng_get_probe_list_head(void);
 585 int lttng_session_active(void);
 586
 587 #ifdef __cplusplus
 588 }
 589 #endif
 590
 591 #endif /* _LTTNG_UST_EVENTS_H */