src/common/events.h

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright 2019 (c) Francis Deslauriers <francis.deslauriers@efficios.com>
   5  */
   6
   7 #ifndef _UST_COMMON_UST_EVENTS_H
   8 #define _UST_COMMON_UST_EVENTS_H
   9
  10 #include <limits.h>
  11 #include <stdint.h>
  12
  13 #include <urcu/list.h>
  14 #include <urcu/hlist.h>
  15
  16 #include <lttng/ust-events.h>
  17
  18 #include "common/macros.h"
  19 #include "common/ust-context-provider.h"
  20
  21 /*
  22  * The context procname length is part of the LTTng-UST ABI.
  23  * TODO: At the next breaking protocol bump, all users of this macro
  24  * should instead use LTTNG_UST_ABI_PROCNAME_LEN.
  25  */
  26 #define LTTNG_UST_CONTEXT_PROCNAME_LEN  17
  27
  28 struct lttng_ust_abi_obj;
  29 struct lttng_event_notifier_group;
  30
  31 union lttng_ust_abi_args {
  32         struct {
  33                 void *chan_data;
  34                 int wakeup_fd;
  35         } channel;
  36         struct {
  37                 int shm_fd;
  38                 int wakeup_fd;
  39         } stream;
  40         struct {
  41                 struct lttng_ust_abi_field_iter entry;
  42         } field_list;
  43         struct {
  44                 char *ctxname;
  45         } app_context;
  46         struct {
  47                 int event_notifier_notif_fd;
  48         } event_notifier_handle;
  49         struct {
  50                 void *counter_data;
  51         } counter;
  52         struct {
  53                 int shm_fd;
  54         } counter_shm;
  55 };
  56
  57 struct lttng_ust_abi_objd_ops {
  58         long (*cmd)(int objd, unsigned int cmd, unsigned long arg,
  59                 union lttng_ust_abi_args *args, void *owner);
  60         int (*release)(int objd);
  61 };
  62
  63 enum lttng_enabler_format_type {
  64         LTTNG_ENABLER_FORMAT_STAR_GLOB,
  65         LTTNG_ENABLER_FORMAT_EVENT,
  66 };
  67
  68 /*
  69  * Enabler field, within whatever object is enabling an event. Target of
  70  * backward reference.
  71  */
  72 struct lttng_enabler {
  73         enum lttng_enabler_format_type format_type;
  74
  75         /* head list of struct lttng_ust_filter_bytecode_node */
  76         struct cds_list_head filter_bytecode_head;
  77         /* head list of struct lttng_ust_excluder_node */
  78         struct cds_list_head excluder_head;
  79
  80         struct lttng_ust_abi_event event_param;
  81         unsigned int enabled:1;
  82 };
  83
  84 struct lttng_event_enabler {
  85         struct lttng_enabler base;
  86         struct cds_list_head node;      /* per-session list of enablers */
  87         struct lttng_ust_channel_buffer *chan;
  88         /*
  89          * Unused, but kept around to make it explicit that the tracer can do
  90          * it.
  91          */
  92         struct lttng_ust_ctx *ctx;
  93 };
  94
  95 struct lttng_event_notifier_enabler {
  96         struct lttng_enabler base;
  97         uint64_t error_counter_index;
  98         struct cds_list_head node;      /* per-app list of event_notifier enablers */
  99         struct cds_list_head capture_bytecode_head;
 100         struct lttng_event_notifier_group *group; /* weak ref */
 101         uint64_t user_token;            /* User-provided token */
 102         uint64_t num_captures;
 103 };
 104
 105 enum lttng_ust_bytecode_type {
 106         LTTNG_UST_BYTECODE_TYPE_FILTER,
 107         LTTNG_UST_BYTECODE_TYPE_CAPTURE,
 108 };
 109
 110 struct lttng_ust_bytecode_node {
 111         enum lttng_ust_bytecode_type type;
 112         struct cds_list_head node;
 113         struct lttng_enabler *enabler;
 114         struct  {
 115                 uint32_t len;
 116                 uint32_t reloc_offset;
 117                 uint64_t seqnum;
 118                 char data[];
 119         } bc;
 120 };
 121
 122 /*
 123  * Bytecode interpreter return value.
 124  */
 125 enum lttng_ust_bytecode_interpreter_ret {
 126         LTTNG_UST_BYTECODE_INTERPRETER_ERROR = -1,
 127         LTTNG_UST_BYTECODE_INTERPRETER_OK = 0,
 128 };
 129
 130 struct lttng_interpreter_output;
 131 struct lttng_ust_bytecode_runtime_private;
 132
 133 enum lttng_ust_bytecode_filter_result {
 134         LTTNG_UST_BYTECODE_FILTER_ACCEPT = 0,
 135         LTTNG_UST_BYTECODE_FILTER_REJECT = 1,
 136 };
 137
 138 struct lttng_ust_bytecode_filter_ctx {
 139         enum lttng_ust_bytecode_filter_result result;
 140 };
 141
 142 struct lttng_ust_excluder_node {
 143         struct cds_list_head node;
 144         struct lttng_enabler *enabler;
 145         /*
 146          * struct lttng_ust_event_exclusion had variable sized array,
 147          * must be last field.
 148          */
 149         struct lttng_ust_abi_event_exclusion excluder;
 150 };
 151
 152 /* Data structures used by the tracer. */
 153
 154 struct tp_list_entry {
 155         struct lttng_ust_abi_tracepoint_iter tp;
 156         struct cds_list_head head;
 157 };
 158
 159 struct lttng_ust_tracepoint_list {
 160         struct tp_list_entry *iter;
 161         struct cds_list_head head;
 162 };
 163
 164 struct tp_field_list_entry {
 165         struct lttng_ust_abi_field_iter field;
 166         struct cds_list_head head;
 167 };
 168
 169 struct lttng_ust_field_list {
 170         struct tp_field_list_entry *iter;
 171         struct cds_list_head head;
 172 };
 173
 174 /*
 175  * Objects in a linked-list of enablers, owned by an event or event_notifier.
 176  * This is used because an event (or a event_notifier) can be enabled by more
 177  * than one enabler and we want a quick way to iterate over all enablers of an
 178  * object.
 179  *
 180  * For example, event rules "my_app:a*" and "my_app:ab*" will both match the
 181  * event with the name "my_app:abc".
 182  */
 183 struct lttng_enabler_ref {
 184         struct cds_list_head node;              /* enabler ref list */
 185         struct lttng_enabler *ref;              /* backward ref */
 186 };
 187
 188 #define LTTNG_COUNTER_DIMENSION_MAX     8
 189 struct lttng_counter_dimension {
 190         uint64_t size;
 191         uint64_t underflow_index;
 192         uint64_t overflow_index;
 193         uint8_t has_underflow;
 194         uint8_t has_overflow;
 195 };
 196
 197 struct lttng_counter_ops {
 198         struct lib_counter *(*counter_create)(size_t nr_dimensions,
 199                         const struct lttng_counter_dimension *dimensions,
 200                         int64_t global_sum_step,
 201                         int global_counter_fd,
 202                         int nr_counter_cpu_fds,
 203                         const int *counter_cpu_fds,
 204                         bool is_daemon);
 205         void (*counter_destroy)(struct lib_counter *counter);
 206         int (*counter_add)(struct lib_counter *counter,
 207                         const size_t *dimension_indexes, int64_t v);
 208         int (*counter_read)(struct lib_counter *counter,
 209                         const size_t *dimension_indexes, int cpu,
 210                         int64_t *value, bool *overflow, bool *underflow);
 211         int (*counter_aggregate)(struct lib_counter *counter,
 212                         const size_t *dimension_indexes, int64_t *value,
 213                         bool *overflow, bool *underflow);
 214         int (*counter_clear)(struct lib_counter *counter, const size_t *dimension_indexes);
 215 };
 216
 217 struct lttng_counter {
 218         int objd;
 219         struct lttng_event_notifier_group *event_notifier_group;    /* owner */
 220         struct lttng_counter_transport *transport;
 221         struct lib_counter *counter;
 222         struct lttng_counter_ops *ops;
 223 };
 224
 225 #define LTTNG_UST_EVENT_HT_BITS         12
 226 #define LTTNG_UST_EVENT_HT_SIZE         (1U << LTTNG_UST_EVENT_HT_BITS)
 227
 228 struct lttng_ust_event_ht {
 229         struct cds_hlist_head table[LTTNG_UST_EVENT_HT_SIZE];
 230 };
 231
 232 #define LTTNG_UST_EVENT_NOTIFIER_HT_BITS                12
 233 #define LTTNG_UST_EVENT_NOTIFIER_HT_SIZE                (1U << LTTNG_UST_EVENT_NOTIFIER_HT_BITS)
 234 struct lttng_ust_event_notifier_ht {
 235         struct cds_hlist_head table[LTTNG_UST_EVENT_NOTIFIER_HT_SIZE];
 236 };
 237
 238 #define LTTNG_UST_ENUM_HT_BITS          12
 239 #define LTTNG_UST_ENUM_HT_SIZE          (1U << LTTNG_UST_ENUM_HT_BITS)
 240
 241 struct lttng_ust_enum_ht {
 242         struct cds_hlist_head table[LTTNG_UST_ENUM_HT_SIZE];
 243 };
 244
 245 struct lttng_event_notifier_group {
 246         int objd;
 247         void *owner;
 248         int notification_fd;
 249         struct cds_list_head node;              /* Event notifier group handle list */
 250         struct cds_list_head enablers_head;
 251         struct cds_list_head event_notifiers_head; /* list of event_notifiers */
 252         struct lttng_ust_event_notifier_ht event_notifiers_ht; /* hashtable of event_notifiers */
 253         struct lttng_ust_ctx *ctx;              /* contexts for filters. */
 254
 255         struct lttng_counter *error_counter;
 256         size_t error_counter_len;
 257 };
 258
 259 struct lttng_transport {
 260         const char *name;
 261         struct cds_list_head node;
 262         struct lttng_ust_channel_buffer_ops ops;
 263         const struct lttng_ust_ring_buffer_config *client_config;
 264 };
 265
 266 struct lttng_counter_transport {
 267         const char *name;
 268         struct cds_list_head node;
 269         struct lttng_counter_ops ops;
 270         const struct lib_counter_config *client_config;
 271 };
 272
 273 struct lttng_ust_event_common_private {
 274         struct lttng_ust_event_common *pub;     /* Public event interface */
 275
 276         const struct lttng_ust_event_desc *desc;
 277         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 278         struct cds_list_head enablers_ref_head;
 279         int registered;                         /* has reg'd tracepoint probe */
 280         uint64_t user_token;
 281
 282         int has_enablers_without_filter_bytecode;
 283         /* list of struct lttng_ust_bytecode_runtime, sorted by seqnum */
 284         struct cds_list_head filter_bytecode_runtime_head;
 285 };
 286
 287 struct lttng_ust_event_recorder_private {
 288         struct lttng_ust_event_common_private parent;
 289
 290         struct lttng_ust_event_recorder *pub;   /* Public event interface */
 291         struct cds_list_head node;              /* Event recorder list */
 292         struct cds_hlist_node hlist;            /* Hash table of event recorders */
 293         struct lttng_ust_ctx *ctx;
 294         unsigned int id;
 295 };
 296
 297 struct lttng_ust_event_notifier_private {
 298         struct lttng_ust_event_common_private parent;
 299
 300         struct lttng_ust_event_notifier *pub;   /* Public event notifier interface */
 301         struct lttng_event_notifier_group *group; /* weak ref */
 302         size_t num_captures;                    /* Needed to allocate the msgpack array. */
 303         uint64_t error_counter_index;
 304         struct cds_list_head node;              /* Event notifier list */
 305         struct cds_hlist_node hlist;            /* Hash table of event notifiers */
 306         struct cds_list_head capture_bytecode_runtime_head;
 307 };
 308
 309 struct lttng_ust_bytecode_runtime {
 310         enum lttng_ust_bytecode_type type;
 311         struct lttng_ust_bytecode_node *bc;
 312         int link_failed;
 313         int (*interpreter_func)(struct lttng_ust_bytecode_runtime *bytecode_runtime,
 314                         const char *interpreter_stack_data,
 315                         struct lttng_ust_probe_ctx *probe_ctx,
 316                         void *ctx);
 317         struct cds_list_head node;              /* list of bytecode runtime in event */
 318         /*
 319          * Pointer to a URCU-protected pointer owned by an `struct
 320          * lttng_session`or `struct lttng_event_notifier_group`.
 321          */
 322         struct lttng_ust_ctx **pctx;
 323 };
 324
 325 struct lttng_ust_session_private {
 326         struct lttng_ust_session *pub;          /* Public session interface */
 327
 328         int been_active;                        /* Been active ? */
 329         int objd;                               /* Object associated */
 330         struct cds_list_head chan_head;         /* Channel list head */
 331         struct cds_list_head events_head;       /* list of events */
 332         struct cds_list_head node;              /* Session list */
 333
 334         /* List of enablers */
 335         struct cds_list_head enablers_head;
 336         struct lttng_ust_event_ht events_ht;    /* ht of events */
 337         void *owner;                            /* object owner */
 338         int tstate:1;                           /* Transient enable state */
 339
 340         int statedump_pending:1;
 341
 342         struct lttng_ust_enum_ht enums_ht;      /* ht of enumerations */
 343         struct cds_list_head enums_head;
 344         struct lttng_ust_ctx *ctx;              /* contexts for filters. */
 345
 346         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 347         bool uuid_set;                          /* Is uuid set ? */
 348 };
 349
 350 struct lttng_enum {
 351         const struct lttng_ust_enum_desc *desc;
 352         struct lttng_ust_session *session;
 353         struct cds_list_head node;              /* Enum list in session */
 354         struct cds_hlist_node hlist;            /* Session ht of enums */
 355         uint64_t id;                            /* Enumeration ID in sessiond */
 356 };
 357
 358 struct lttng_ust_shm_handle;
 359
 360 struct lttng_ust_channel_buffer_ops_private {
 361         struct lttng_ust_channel_buffer_ops *pub;       /* Public channel buffer ops interface */
 362
 363         struct lttng_ust_channel_buffer *(*channel_create)(const char *name,
 364                         void *buf_addr,
 365                         size_t subbuf_size, size_t num_subbuf,
 366                         unsigned int switch_timer_interval,
 367                         unsigned int read_timer_interval,
 368                         unsigned char *uuid,
 369                         uint32_t chan_id,
 370                         const int *stream_fds, int nr_stream_fds,
 371                         int64_t blocking_timeout);
 372         void (*channel_destroy)(struct lttng_ust_channel_buffer *chan);
 373         /*
 374          * packet_avail_size returns the available size in the current
 375          * packet. Note that the size returned is only a hint, since it
 376          * may change due to concurrent writes.
 377          */
 378         size_t (*packet_avail_size)(struct lttng_ust_channel_buffer *chan);
 379         int (*is_finalized)(struct lttng_ust_channel_buffer *chan);
 380         int (*is_disabled)(struct lttng_ust_channel_buffer *chan);
 381         int (*flush_buffer)(struct lttng_ust_channel_buffer *chan);
 382 };
 383
 384 struct lttng_ust_channel_common_private {
 385         struct lttng_ust_channel_common *pub;   /* Public channel interface */
 386
 387         int objd;                               /* Object associated with channel. */
 388         int tstate:1;                           /* Transient enable state */
 389 };
 390
 391 struct lttng_ust_channel_buffer_private {
 392         struct lttng_ust_channel_common_private parent;
 393
 394         struct lttng_ust_channel_buffer *pub;   /* Public channel buffer interface */
 395         struct cds_list_head node;              /* Channel list in session */
 396         int header_type;                        /* 0: unset, 1: compact, 2: large */
 397         unsigned int id;                        /* Channel ID */
 398         enum lttng_ust_abi_chan_type type;
 399         struct lttng_ust_ctx *ctx;
 400         struct lttng_ust_ring_buffer_channel *rb_chan;  /* Ring buffer channel */
 401         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 402 };
 403
 404 /*
 405  * IMPORTANT: this structure is part of the ABI between the consumer
 406  * daemon and the UST library within traced applications. Changing it
 407  * breaks the UST communication protocol.
 408  *
 409  * TODO: remove unused fields on next UST communication protocol
 410  * breaking update.
 411  */
 412 struct lttng_ust_abi_channel_config {
 413         void *unused1;
 414         int unused2;
 415         void *unused3;
 416         void *unused4;
 417         int unused5;
 418         unsigned int _deprecated1;
 419         unsigned int _deprecated2;
 420         struct cds_list_head unused6;
 421         void *unused7;
 422         int unused8;
 423         void *unused9;
 424         unsigned int _deprecated3:1;
 425
 426         /* Channel ID */
 427         unsigned int id;
 428         enum lttng_ust_abi_chan_type unused10;
 429         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 430         int unused11:1;
 431 };
 432
 433 /* Global (filter), event and channel contexts. */
 434 struct lttng_ust_ctx {
 435         struct lttng_ust_ctx_field *fields;
 436         unsigned int nr_fields;
 437         unsigned int allocated_fields;
 438         unsigned int largest_align;
 439 };
 440
 441 struct lttng_ust_registered_probe {
 442         const struct lttng_ust_probe_desc *desc;
 443
 444         struct cds_list_head head;              /* chain registered probes */
 445         struct cds_list_head lazy_init_head;
 446         int lazy;                               /* lazy registration */
 447 };
 448
 449 /*
 450  * Context field
 451  */
 452
 453 struct lttng_ust_ctx_field {
 454         const struct lttng_ust_event_field *event_field;
 455         size_t (*get_size)(void *priv, struct lttng_ust_probe_ctx *probe_ctx,
 456                         size_t offset);
 457         void (*record)(void *priv, struct lttng_ust_probe_ctx *probe_ctx,
 458                         struct lttng_ust_ring_buffer_ctx *ctx,
 459                         struct lttng_ust_channel_buffer *chan);
 460         void (*get_value)(void *priv, struct lttng_ust_probe_ctx *probe_ctx,
 461                         struct lttng_ust_ctx_value *value);
 462         void (*destroy)(void *priv);
 463         void *priv;
 464 };
 465
 466 static inline
 467 const struct lttng_ust_type_integer *lttng_ust_get_type_integer(const struct lttng_ust_type_common *type)
 468 {
 469         if (type->type != lttng_ust_type_integer)
 470                 return NULL;
 471         return caa_container_of(type, const struct lttng_ust_type_integer, parent);
 472 }
 473
 474 static inline
 475 const struct lttng_ust_type_float *lttng_ust_get_type_float(const struct lttng_ust_type_common *type)
 476 {
 477         if (type->type != lttng_ust_type_float)
 478                 return NULL;
 479         return caa_container_of(type, const struct lttng_ust_type_float, parent);
 480 }
 481
 482 static inline
 483 const struct lttng_ust_type_string *lttng_ust_get_type_string(const struct lttng_ust_type_common *type)
 484 {
 485         if (type->type != lttng_ust_type_string)
 486                 return NULL;
 487         return caa_container_of(type, const struct lttng_ust_type_string, parent);
 488 }
 489
 490 static inline
 491 const struct lttng_ust_type_enum *lttng_ust_get_type_enum(const struct lttng_ust_type_common *type)
 492 {
 493         if (type->type != lttng_ust_type_enum)
 494                 return NULL;
 495         return caa_container_of(type, const struct lttng_ust_type_enum, parent);
 496 }
 497
 498 static inline
 499 const struct lttng_ust_type_array *lttng_ust_get_type_array(const struct lttng_ust_type_common *type)
 500 {
 501         if (type->type != lttng_ust_type_array)
 502                 return NULL;
 503         return caa_container_of(type, const struct lttng_ust_type_array, parent);
 504 }
 505
 506 static inline
 507 const struct lttng_ust_type_sequence *lttng_ust_get_type_sequence(const struct lttng_ust_type_common *type)
 508 {
 509         if (type->type != lttng_ust_type_sequence)
 510                 return NULL;
 511         return caa_container_of(type, const struct lttng_ust_type_sequence, parent);
 512 }
 513
 514 static inline
 515 const struct lttng_ust_type_struct *lttng_ust_get_type_struct(const struct lttng_ust_type_common *type)
 516 {
 517         if (type->type != lttng_ust_type_struct)
 518                 return NULL;
 519         return caa_container_of(type, const struct lttng_ust_type_struct, parent);
 520 }
 521
 522 #define lttng_ust_static_type_integer(_size, _alignment, _signedness, _byte_order, _base)               \
 523         ((const struct lttng_ust_type_common *) LTTNG_UST_COMPOUND_LITERAL(const struct lttng_ust_type_integer, { \
 524                 .parent = {                                                                             \
 525                         .type = lttng_ust_type_integer,                                                 \
 526                 },                                                                                      \
 527                 .struct_size = sizeof(struct lttng_ust_type_integer),                                   \
 528                 .size = (_size),                                                                        \
 529                 .alignment = (_alignment),                                                              \
 530                 .signedness = (_signedness),                                                            \
 531                 .reverse_byte_order = (_byte_order) != LTTNG_UST_BYTE_ORDER,                                    \
 532                 .base = (_base),                                                                        \
 533         }))
 534
 535 #define lttng_ust_static_type_array_text(_length)                                                       \
 536         ((const struct lttng_ust_type_common *) LTTNG_UST_COMPOUND_LITERAL(const struct lttng_ust_type_array, { \
 537                 .parent = {                                                                             \
 538                         .type = lttng_ust_type_array,                                                   \
 539                 },                                                                                      \
 540                 .struct_size = sizeof(struct lttng_ust_type_array),                                     \
 541                 .length = (_length),                                                                    \
 542                 .alignment = 0,                                                                         \
 543                 .encoding = lttng_ust_string_encoding_UTF8,                                             \
 544                 .elem_type = lttng_ust_static_type_integer(sizeof(char) * CHAR_BIT,                     \
 545                                 lttng_ust_rb_alignof(char) * CHAR_BIT, lttng_ust_is_signed_type(char),  \
 546                                 LTTNG_UST_BYTE_ORDER, 10),                                                      \
 547         }))
 548
 549 #define lttng_ust_static_event_field(_name, _type, _nowrite, _nofilter)                                 \
 550         LTTNG_UST_COMPOUND_LITERAL(const struct lttng_ust_event_field, {                                \
 551                 .struct_size = sizeof(struct lttng_ust_event_field),                                    \
 552                 .name = (_name),                                                                        \
 553                 .type = (_type),                                                                        \
 554                 .nowrite = (_nowrite),                                                                  \
 555                 .nofilter = (_nofilter),                                                                \
 556         })
 557
 558 #define lttng_ust_static_ctx_field(_event_field, _get_size, _record, _get_value, _destroy, _priv)       \
 559         LTTNG_UST_COMPOUND_LITERAL(const struct lttng_ust_ctx_field, {                          \
 560                 .event_field = (_event_field),                                                          \
 561                 .get_size = (_get_size),                                                                \
 562                 .record = (_record),                                                                    \
 563                 .get_value = (_get_value),                                                              \
 564                 .destroy = (_destroy),                                                                  \
 565                 .priv = (_priv),                                                                        \
 566         })
 567
 568 static inline
 569 struct lttng_enabler *lttng_event_enabler_as_enabler(
 570                 struct lttng_event_enabler *event_enabler)
 571 {
 572         return &event_enabler->base;
 573 }
 574
 575 static inline
 576 struct lttng_enabler *lttng_event_notifier_enabler_as_enabler(
 577                 struct lttng_event_notifier_enabler *event_notifier_enabler)
 578 {
 579         return &event_notifier_enabler->base;
 580 }
 581
 582
 583
 584 /* This is ABI between liblttng-ust and liblttng-ust-dl */
 585 void lttng_ust_dl_update(void *ip);
 586
 587 struct lttng_enum *lttng_ust_enum_get_from_desc(struct lttng_ust_session *session,
 588                 const struct lttng_ust_enum_desc *enum_desc)
 589         __attribute__((visibility("hidden")));
 590
 591
 592 #endif /* _UST_COMMON_UST_EVENTS_H */