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_NR_CLIENT_TYPES,
  58 };
  59
  60 /* Type description */
  61
  62 /* Update the astract_types name table in lttng-types.c along with this enum */
  63 enum lttng_abstract_types {
  64         atype_integer,
  65         atype_enum,
  66         atype_array,
  67         atype_sequence,
  68         atype_string,
  69         atype_float,
  70         NR_ABSTRACT_TYPES,
  71 };
  72
  73 /* Update the string_encodings name table in lttng-types.c along with this enum */
  74 enum lttng_string_encodings {
  75         lttng_encode_none = 0,
  76         lttng_encode_UTF8 = 1,
  77         lttng_encode_ASCII = 2,
  78         NR_STRING_ENCODINGS,
  79 };
  80
  81 #define LTTNG_UST_ENUM_ENTRY_PADDING    16
  82 struct lttng_enum_entry {
  83         unsigned long long start, end;  /* start and end are inclusive */
  84         const char *string;
  85         char padding[LTTNG_UST_ENUM_ENTRY_PADDING];
  86 };
  87
  88 #define __type_integer(_type, _byte_order, _base, _encoding)    \
  89         {                                                       \
  90             .atype = atype_integer,                             \
  91             .u.basic.integer =                                  \
  92                 {                                               \
  93                   .size = sizeof(_type) * CHAR_BIT,             \
  94                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
  95                   .signedness = lttng_is_signed_type(_type),    \
  96                   .reverse_byte_order = _byte_order != BYTE_ORDER,      \
  97                   .base = _base,                                \
  98                   .encoding = lttng_encode_##_encoding,         \
  99                 },                                              \
 100         }                                                       \
 101
 102 #define LTTNG_UST_INTEGER_TYPE_PADDING  24
 103 struct lttng_integer_type {
 104         unsigned int size;              /* in bits */
 105         unsigned short alignment;       /* in bits */
 106         unsigned int signedness:1;
 107         unsigned int reverse_byte_order:1;
 108         unsigned int base;              /* 2, 8, 10, 16, for pretty print */
 109         enum lttng_string_encodings encoding;
 110         char padding[LTTNG_UST_INTEGER_TYPE_PADDING];
 111 };
 112
 113 /*
 114  * Only float and double are supported. long double is not supported at
 115  * the moment.
 116  */
 117 #define _float_mant_dig(_type)                                          \
 118         (sizeof(_type) == sizeof(float) ? FLT_MANT_DIG                  \
 119                 : (sizeof(_type) == sizeof(double) ? DBL_MANT_DIG       \
 120                 : 0))
 121
 122 #define __type_float(_type)                                     \
 123         {                                                       \
 124             .atype = atype_float,                               \
 125             .u.basic._float =                                   \
 126                 {                                               \
 127                   .exp_dig = sizeof(_type) * CHAR_BIT           \
 128                                 - _float_mant_dig(_type),       \
 129                   .mant_dig = _float_mant_dig(_type),           \
 130                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
 131                   .reverse_byte_order = BYTE_ORDER != FLOAT_WORD_ORDER, \
 132                 },                                              \
 133         }                                                       \
 134
 135 #define LTTNG_UST_FLOAT_TYPE_PADDING    24
 136 struct lttng_float_type {
 137         unsigned int exp_dig;           /* exponent digits, in bits */
 138         unsigned int mant_dig;          /* mantissa digits, in bits */
 139         unsigned short alignment;       /* in bits */
 140         unsigned int reverse_byte_order:1;
 141         char padding[LTTNG_UST_FLOAT_TYPE_PADDING];
 142 };
 143
 144 #define LTTNG_UST_BASIC_TYPE_PADDING    128
 145 union _lttng_basic_type {
 146         struct lttng_integer_type integer;
 147         struct {
 148                 const char *name;
 149         } enumeration;
 150         struct {
 151                 enum lttng_string_encodings encoding;
 152         } string;
 153         struct lttng_float_type _float;
 154         char padding[LTTNG_UST_BASIC_TYPE_PADDING];
 155 };
 156
 157 struct lttng_basic_type {
 158         enum lttng_abstract_types atype;
 159         union {
 160                 union _lttng_basic_type basic;
 161         } u;
 162 };
 163
 164 #define LTTNG_UST_TYPE_PADDING  128
 165 struct lttng_type {
 166         enum lttng_abstract_types atype;
 167         union {
 168                 union _lttng_basic_type basic;
 169                 struct {
 170                         struct lttng_basic_type elem_type;
 171                         unsigned int length;            /* num. elems. */
 172                 } array;
 173                 struct {
 174                         struct lttng_basic_type length_type;
 175                         struct lttng_basic_type elem_type;
 176                 } sequence;
 177                 char padding[LTTNG_UST_TYPE_PADDING];
 178         } u;
 179 };
 180
 181 #define LTTNG_UST_ENUM_TYPE_PADDING     24
 182 struct lttng_enum {
 183         const char *name;
 184         struct lttng_type container_type;
 185         const struct lttng_enum_entry *entries;
 186         unsigned int len;
 187         char padding[LTTNG_UST_ENUM_TYPE_PADDING];
 188 };
 189
 190 /*
 191  * Event field description
 192  *
 193  * IMPORTANT: this structure is part of the ABI between the probe and
 194  * UST. Fields need to be only added at the end, never reordered, never
 195  * removed.
 196  */
 197
 198 #define LTTNG_UST_EVENT_FIELD_PADDING   28
 199 struct lttng_event_field {
 200         const char *name;
 201         struct lttng_type type;
 202         unsigned int nowrite;   /* do not write into trace */
 203         char padding[LTTNG_UST_EVENT_FIELD_PADDING];
 204 };
 205
 206 #define LTTNG_UST_CTX_FIELD_PADDING     40
 207 struct lttng_ctx_field {
 208         struct lttng_event_field event_field;
 209         size_t (*get_size)(size_t offset);
 210         void (*record)(struct lttng_ctx_field *field,
 211                        struct lttng_ust_lib_ring_buffer_ctx *ctx,
 212                        struct lttng_channel *chan);
 213         union {
 214                 char padding[LTTNG_UST_CTX_FIELD_PADDING];
 215         } u;
 216         void (*destroy)(struct lttng_ctx_field *field);
 217 };
 218
 219 #define LTTNG_UST_CTX_PADDING   24
 220 struct lttng_ctx {
 221         struct lttng_ctx_field *fields;
 222         unsigned int nr_fields;
 223         unsigned int allocated_fields;
 224         char padding[LTTNG_UST_CTX_PADDING];
 225 };
 226
 227 #define LTTNG_UST_EVENT_DESC_PADDING    40
 228 struct lttng_event_desc {
 229         const char *name;
 230         void (*probe_callback)(void);
 231         const struct lttng_event_ctx *ctx;      /* context */
 232         const struct lttng_event_field *fields; /* event payload */
 233         unsigned int nr_fields;
 234         const int **loglevel;
 235         const char *signature;  /* Argument types/names received */
 236         union {
 237                 struct {
 238                         const char **model_emf_uri;
 239                 } ext;
 240                 char padding[LTTNG_UST_EVENT_DESC_PADDING];
 241         } u;
 242 };
 243
 244 #define LTTNG_UST_PROBE_DESC_PADDING    20
 245 struct lttng_probe_desc {
 246         const char *provider;
 247         const struct lttng_event_desc **event_desc;
 248         unsigned int nr_events;
 249         struct cds_list_head head;              /* chain registered probes */
 250         struct cds_list_head lazy_init_head;
 251         int lazy;                               /* lazy registration */
 252         char padding[LTTNG_UST_PROBE_DESC_PADDING];
 253 };
 254
 255 /* Data structures used by the tracer. */
 256
 257 enum lttng_enabler_type {
 258         LTTNG_ENABLER_WILDCARD,
 259         LTTNG_ENABLER_EVENT,
 260 };
 261
 262 /*
 263  * Enabler field, within whatever object is enabling an event. Target of
 264  * backward reference.
 265  */
 266 struct lttng_enabler {
 267         enum lttng_enabler_type type;
 268
 269         /* head list of struct lttng_ust_filter_bytecode_node */
 270         struct cds_list_head filter_bytecode_head;
 271         struct cds_list_head node;      /* per-session list of enablers */
 272
 273         struct lttng_ust_event event_param;
 274         struct lttng_channel *chan;
 275         struct lttng_ctx *ctx;
 276         unsigned int enabled:1;
 277 };
 278
 279 struct tp_list_entry {
 280         struct lttng_ust_tracepoint_iter tp;
 281         struct cds_list_head head;
 282 };
 283
 284 struct lttng_ust_tracepoint_list {
 285         struct tp_list_entry *iter;
 286         struct cds_list_head head;
 287 };
 288
 289 struct tp_field_list_entry {
 290         struct lttng_ust_field_iter field;
 291         struct cds_list_head head;
 292 };
 293
 294 struct lttng_ust_field_list {
 295         struct tp_field_list_entry *iter;
 296         struct cds_list_head head;
 297 };
 298
 299 struct ust_pending_probe;
 300 struct lttng_event;
 301
 302 struct lttng_ust_filter_bytecode_node {
 303         struct cds_list_head node;
 304         struct lttng_enabler *enabler;
 305         /*
 306          * struct lttng_ust_filter_bytecode has var. sized array, must
 307          * be last field.
 308          */
 309         struct lttng_ust_filter_bytecode bc;
 310 };
 311
 312 /*
 313  * Filter return value masks.
 314  */
 315 enum lttng_filter_ret {
 316         LTTNG_FILTER_DISCARD = 0,
 317         LTTNG_FILTER_RECORD_FLAG = (1ULL << 0),
 318         /* Other bits are kept for future use. */
 319 };
 320
 321 struct lttng_bytecode_runtime {
 322         /* Associated bytecode */
 323         struct lttng_ust_filter_bytecode_node *bc;
 324         uint64_t (*filter)(void *filter_data, const char *filter_stack_data);
 325         int link_failed;
 326         struct cds_list_head node;      /* list of bytecode runtime in event */
 327 };
 328
 329 /*
 330  * Objects in a linked-list of enablers, owned by an event.
 331  */
 332 struct lttng_enabler_ref {
 333         struct cds_list_head node;              /* enabler ref list */
 334         struct lttng_enabler *ref;              /* backward ref */
 335 };
 336
 337 /*
 338  * lttng_event structure is referred to by the tracing fast path. It
 339  * must be kept small.
 340  *
 341  * IMPORTANT: this structure is part of the ABI between the probe and
 342  * UST. Fields need to be only added at the end, never reordered, never
 343  * removed.
 344  */
 345 struct lttng_event {
 346         /* LTTng-UST 2.0 starts here */
 347         unsigned int id;
 348         struct lttng_channel *chan;
 349         int enabled;
 350         const struct lttng_event_desc *desc;
 351         void *_deprecated1;
 352         struct lttng_ctx *ctx;
 353         enum lttng_ust_instrumentation instrumentation;
 354         union {
 355         } u;
 356         struct cds_list_head node;              /* Event list in session */
 357         struct cds_list_head _deprecated2;
 358         void *_deprecated3;
 359         unsigned int metadata_dumped:1;
 360
 361         /* LTTng-UST 2.1 starts here */
 362         /* list of struct lttng_bytecode_runtime, sorted by seqnum */
 363         struct cds_list_head bytecode_runtime_head;
 364         int has_enablers_without_bytecode;
 365         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 366         struct cds_list_head enablers_ref_head;
 367         struct cds_hlist_node hlist;    /* session ht of events */
 368 };
 369
 370 struct channel;
 371 struct lttng_ust_shm_handle;
 372
 373 /*
 374  * IMPORTANT: this structure is part of the ABI between the probe and
 375  * UST. Fields need to be only added at the end, never reordered, never
 376  * removed.
 377  */
 378 struct lttng_channel_ops {
 379         struct lttng_channel *(*channel_create)(const char *name,
 380                         void *buf_addr,
 381                         size_t subbuf_size, size_t num_subbuf,
 382                         unsigned int switch_timer_interval,
 383                         unsigned int read_timer_interval,
 384                         unsigned char *uuid);
 385         void (*channel_destroy)(struct lttng_channel *chan);
 386         int (*event_reserve)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 387                              uint32_t event_id);
 388         void (*event_commit)(struct lttng_ust_lib_ring_buffer_ctx *ctx);
 389         void (*event_write)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 390                         const void *src, size_t len);
 391         /*
 392          * packet_avail_size returns the available size in the current
 393          * packet. Note that the size returned is only a hint, since it
 394          * may change due to concurrent writes.
 395          */
 396         size_t (*packet_avail_size)(struct channel *chan,
 397                                     struct lttng_ust_shm_handle *handle);
 398         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 399         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 400         int (*is_finalized)(struct channel *chan);
 401         int (*is_disabled)(struct channel *chan);
 402         int (*flush_buffer)(struct channel *chan, struct lttng_ust_shm_handle *handle);
 403 };
 404
 405 /*
 406  * IMPORTANT: this structure is part of the ABI between the probe and
 407  * UST. Fields need to be only added at the end, never reordered, never
 408  * removed.
 409  */
 410 struct lttng_channel {
 411         /*
 412          * The pointers located in this private data are NOT safe to be
 413          * dereferenced by the consumer. The only operations the
 414          * consumer process is designed to be allowed to do is to read
 415          * and perform subbuffer flush.
 416          */
 417         struct channel *chan;           /* Channel buffers */
 418         int enabled;
 419         struct lttng_ctx *ctx;
 420         /* Event ID management */
 421         struct lttng_session *session;
 422         int objd;                       /* Object associated to channel */
 423         unsigned int _deprecated1;
 424         unsigned int _deprecated2;
 425         struct cds_list_head node;      /* Channel list in session */
 426         const struct lttng_channel_ops *ops;
 427         int header_type;                /* 0: unset, 1: compact, 2: large */
 428         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
 429         unsigned int metadata_dumped:1;
 430
 431         /* Channel ID */
 432         unsigned int id;
 433         enum lttng_ust_chan_type type;
 434         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 435 };
 436
 437 #define LTTNG_UST_EVENT_HT_BITS         12
 438 #define LTTNG_UST_EVENT_HT_SIZE         (1U << LTTNG_UST_EVENT_HT_BITS)
 439
 440 struct lttng_ust_event_ht {
 441         struct cds_hlist_head table[LTTNG_UST_EVENT_HT_SIZE];
 442 };
 443
 444 /*
 445  * IMPORTANT: this structure is part of the ABI between the probe and
 446  * UST. Fields need to be only added at the end, never reordered, never
 447  * removed.
 448  */
 449 struct lttng_session {
 450         int active;                             /* Is trace session active ? */
 451         int been_active;                        /* Been active ? */
 452         int objd;                               /* Object associated */
 453         struct lttng_channel *metadata;         /* Metadata channel */
 454         struct cds_list_head chan_head;         /* Channel list head */
 455         struct cds_list_head events_head;       /* list of events */
 456         struct cds_list_head _deprecated1;
 457         struct cds_list_head node;              /* Session list */
 458         int _deprecated2;
 459         unsigned int metadata_dumped:1;
 460
 461         /* New UST 2.1 */
 462         /* List of enablers */
 463         struct cds_list_head enablers_head;
 464         struct lttng_ust_event_ht events_ht;    /* ht of events */
 465         void *owner;                            /* object owner */
 466 };
 467
 468 struct lttng_transport {
 469         char *name;
 470         struct cds_list_head node;
 471         struct lttng_channel_ops ops;
 472         const struct lttng_ust_lib_ring_buffer_config *client_config;
 473 };
 474
 475 struct lttng_session *lttng_session_create(void);
 476 int lttng_session_enable(struct lttng_session *session);
 477 int lttng_session_disable(struct lttng_session *session);
 478 void lttng_session_destroy(struct lttng_session *session);
 479
 480 struct lttng_channel *lttng_channel_create(struct lttng_session *session,
 481                                        const char *transport_name,
 482                                        void *buf_addr,
 483                                        size_t subbuf_size, size_t num_subbuf,
 484                                        unsigned int switch_timer_interval,
 485                                        unsigned int read_timer_interval,
 486                                        int **shm_fd, int **wait_fd,
 487                                        uint64_t **memory_map_size,
 488                                        struct lttng_channel *chan_priv_init);
 489
 490 int lttng_channel_enable(struct lttng_channel *channel);
 491 int lttng_channel_disable(struct lttng_channel *channel);
 492
 493 struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type,
 494                 struct lttng_ust_event *event_param,
 495                 struct lttng_channel *chan);
 496 int lttng_enabler_enable(struct lttng_enabler *enabler);
 497 int lttng_enabler_disable(struct lttng_enabler *enabler);
 498 int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
 499                 struct lttng_ust_filter_bytecode_node *bytecode);
 500 int lttng_enabler_attach_context(struct lttng_enabler *enabler,
 501                 struct lttng_ust_context *ctx);
 502
 503 int lttng_attach_context(struct lttng_ust_context *context_param,
 504                 struct lttng_ctx **ctx, struct lttng_session *session);
 505
 506 void lttng_transport_register(struct lttng_transport *transport);
 507 void lttng_transport_unregister(struct lttng_transport *transport);
 508
 509 void synchronize_trace(void);
 510
 511 int lttng_probe_register(struct lttng_probe_desc *desc);
 512 void lttng_probe_unregister(struct lttng_probe_desc *desc);
 513 int lttng_fix_pending_event_desc(const struct lttng_event_desc *desc);
 514 int lttng_probes_init(void);
 515 void lttng_probes_exit(void);
 516 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 517 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p);
 518 void lttng_remove_context_field(struct lttng_ctx **ctx_p,
 519                                 struct lttng_ctx_field *field);
 520 void lttng_destroy_context(struct lttng_ctx *ctx);
 521 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 522 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 523 int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
 524 int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
 525 void lttng_context_vtid_reset(void);
 526 void lttng_context_vpid_reset(void);
 527
 528 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
 529 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
 530 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;
 531
 532 struct lttng_transport *lttng_transport_find(const char *name);
 533
 534 int lttng_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
 535 void lttng_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
 536 struct lttng_ust_tracepoint_iter *
 537         lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
 538 int lttng_probes_get_field_list(struct lttng_ust_field_list *list);
 539 void lttng_probes_prune_field_list(struct lttng_ust_field_list *list);
 540 struct lttng_ust_field_iter *
 541         lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list);
 542
 543 void lttng_filter_event_link_bytecode(struct lttng_event *event);
 544 void lttng_enabler_event_link_bytecode(struct lttng_event *event,
 545                 struct lttng_enabler *enabler);
 546 void lttng_free_event_filter_runtime(struct lttng_event *event);
 547 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime);
 548
 549 struct cds_list_head *lttng_get_probe_list_head(void);
 550 int lttng_session_active(void);
 551
 552 #endif /* _LTTNG_UST_EVENTS_H */