include/lttng/ust-events.h

   1 #ifndef _LTTNG_UST_EVENTS_H
   2 #define _LTTNG_UST_EVENTS_H
   3
   4 /*
   5  * lttng/ust-events.h
   6  *
   7  * Copyright 2010-2012 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   8  *
   9  * Holds LTTng per-session event registry.
  10  *
  11  * Permission is hereby granted, free of charge, to any person obtaining a copy
  12  * of this software and associated documentation files (the "Software"), to deal
  13  * in the Software without restriction, including without limitation the rights
  14  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  15  * copies of the Software, and to permit persons to whom the Software is
  16  * furnished to do so, subject to the following conditions:
  17  *
  18  * The above copyright notice and this permission notice shall be included in
  19  * all copies or substantial portions of the Software.
  20  */
  21
  22 #include <urcu/list.h>
  23 #include <urcu/hlist.h>
  24 #include <stdint.h>
  25 #include <lttng/ust-abi.h>
  26 #include <lttng/ust-tracer.h>
  27 #include <lttng/ust-endian.h>
  28 #include <float.h>
  29
  30 #define LTTNG_UST_UUID_LEN              16
  31
  32 struct ltt_channel;
  33 struct ltt_session;
  34 struct lttng_ust_lib_ring_buffer_ctx;
  35
  36 /*
  37  * Data structures used by tracepoint event declarations, and by the
  38  * tracer. Those structures have padding for future extension.
  39  */
  40
  41 /*
  42  * LTTng client type enumeration. Used by the consumer to map the
  43  * callbacks from its own address space.
  44  */
  45 enum lttng_client_types {
  46         LTTNG_CLIENT_METADATA = 0,
  47         LTTNG_CLIENT_DISCARD = 1,
  48         LTTNG_CLIENT_OVERWRITE = 2,
  49         LTTNG_NR_CLIENT_TYPES,
  50 };
  51
  52 /* Type description */
  53
  54 /* Update the astract_types name table in lttng-types.c along with this enum */
  55 enum abstract_types {
  56         atype_integer,
  57         atype_enum,
  58         atype_array,
  59         atype_sequence,
  60         atype_string,
  61         atype_float,
  62         NR_ABSTRACT_TYPES,
  63 };
  64
  65 /* Update the string_encodings name table in lttng-types.c along with this enum */
  66 enum lttng_string_encodings {
  67         lttng_encode_none = 0,
  68         lttng_encode_UTF8 = 1,
  69         lttng_encode_ASCII = 2,
  70         NR_STRING_ENCODINGS,
  71 };
  72
  73 #define LTTNG_UST_ENUM_ENTRY_PADDING    16
  74 struct lttng_enum_entry {
  75         unsigned long long start, end;  /* start and end are inclusive */
  76         const char *string;
  77         char padding[LTTNG_UST_ENUM_ENTRY_PADDING];
  78 };
  79
  80 #define __type_integer(_type, _byte_order, _base, _encoding)    \
  81         {                                                       \
  82             .atype = atype_integer,                             \
  83             .u.basic.integer =                                  \
  84                 {                                               \
  85                   .size = sizeof(_type) * CHAR_BIT,             \
  86                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
  87                   .signedness = lttng_is_signed_type(_type),    \
  88                   .reverse_byte_order = _byte_order != BYTE_ORDER,      \
  89                   .base = _base,                                \
  90                   .encoding = lttng_encode_##_encoding,         \
  91                 },                                              \
  92         }                                                       \
  93
  94 #define LTTNG_UST_INTEGER_TYPE_PADDING  24
  95 struct lttng_integer_type {
  96         unsigned int size;              /* in bits */
  97         unsigned short alignment;       /* in bits */
  98         unsigned int signedness:1;
  99         unsigned int reverse_byte_order:1;
 100         unsigned int base;              /* 2, 8, 10, 16, for pretty print */
 101         enum lttng_string_encodings encoding;
 102         char padding[LTTNG_UST_INTEGER_TYPE_PADDING];
 103 };
 104
 105 /*
 106  * Only float and double are supported. long double is not supported at
 107  * the moment.
 108  */
 109 #define _float_mant_dig(_type)                                          \
 110         (sizeof(_type) == sizeof(float) ? FLT_MANT_DIG                  \
 111                 : (sizeof(_type) == sizeof(double) ? DBL_MANT_DIG       \
 112                 : 0))
 113
 114 #define __type_float(_type)                                     \
 115         {                                                       \
 116             .atype = atype_float,                               \
 117             .u.basic._float =                                   \
 118                 {                                               \
 119                   .exp_dig = sizeof(_type) * CHAR_BIT           \
 120                                 - _float_mant_dig(_type),       \
 121                   .mant_dig = _float_mant_dig(_type),           \
 122                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
 123                   .reverse_byte_order = BYTE_ORDER != FLOAT_WORD_ORDER, \
 124                 },                                              \
 125         }                                                       \
 126
 127 #define LTTNG_UST_FLOAT_TYPE_PADDING    24
 128 struct lttng_float_type {
 129         unsigned int exp_dig;           /* exponent digits, in bits */
 130         unsigned int mant_dig;          /* mantissa digits, in bits */
 131         unsigned short alignment;       /* in bits */
 132         unsigned int reverse_byte_order:1;
 133         char padding[LTTNG_UST_FLOAT_TYPE_PADDING];
 134 };
 135
 136 #define LTTNG_UST_BASIC_TYPE_PADDING    128
 137 union _lttng_basic_type {
 138         struct lttng_integer_type integer;
 139         struct {
 140                 const char *name;
 141         } enumeration;
 142         struct {
 143                 enum lttng_string_encodings encoding;
 144         } string;
 145         struct lttng_float_type _float;
 146         char padding[LTTNG_UST_BASIC_TYPE_PADDING];
 147 };
 148
 149 struct lttng_basic_type {
 150         enum abstract_types atype;
 151         union {
 152                 union _lttng_basic_type basic;
 153         } u;
 154 };
 155
 156 #define LTTNG_UST_TYPE_PADDING  128
 157 struct lttng_type {
 158         enum abstract_types atype;
 159         union {
 160                 union _lttng_basic_type basic;
 161                 struct {
 162                         struct lttng_basic_type elem_type;
 163                         unsigned int length;            /* num. elems. */
 164                 } array;
 165                 struct {
 166                         struct lttng_basic_type length_type;
 167                         struct lttng_basic_type elem_type;
 168                 } sequence;
 169                 char padding[LTTNG_UST_TYPE_PADDING];
 170         } u;
 171 };
 172
 173 #define LTTNG_UST_ENUM_TYPE_PADDING     24
 174 struct lttng_enum {
 175         const char *name;
 176         struct lttng_type container_type;
 177         const struct lttng_enum_entry *entries;
 178         unsigned int len;
 179         char padding[LTTNG_UST_ENUM_TYPE_PADDING];
 180 };
 181
 182 /*
 183  * Event field description
 184  *
 185  * IMPORTANT: this structure is part of the ABI between the probe and
 186  * UST. Fields need to be only added at the end, never reordered, never
 187  * removed.
 188  */
 189
 190 #define LTTNG_UST_EVENT_FIELD_PADDING   28
 191 struct lttng_event_field {
 192         const char *name;
 193         struct lttng_type type;
 194         unsigned int nowrite;   /* do not write into trace */
 195         char padding[LTTNG_UST_EVENT_FIELD_PADDING];
 196 };
 197
 198 #define LTTNG_UST_CTX_FIELD_PADDING     40
 199 struct lttng_ctx_field {
 200         struct lttng_event_field event_field;
 201         size_t (*get_size)(size_t offset);
 202         void (*record)(struct lttng_ctx_field *field,
 203                        struct lttng_ust_lib_ring_buffer_ctx *ctx,
 204                        struct ltt_channel *chan);
 205         union {
 206                 char padding[LTTNG_UST_CTX_FIELD_PADDING];
 207         } u;
 208         void (*destroy)(struct lttng_ctx_field *field);
 209 };
 210
 211 #define LTTNG_UST_CTX_PADDING   24
 212 struct lttng_ctx {
 213         struct lttng_ctx_field *fields;
 214         unsigned int nr_fields;
 215         unsigned int allocated_fields;
 216         char padding[LTTNG_UST_CTX_PADDING];
 217 };
 218
 219 #define LTTNG_UST_EVENT_DESC_PADDING    40
 220 struct lttng_event_desc {
 221         const char *name;
 222         void (*probe_callback)(void);
 223         const struct lttng_event_ctx *ctx;      /* context */
 224         const struct lttng_event_field *fields; /* event payload */
 225         unsigned int nr_fields;
 226         const int **loglevel;
 227         const char *signature;  /* Argument types/names received */
 228         char padding[LTTNG_UST_EVENT_DESC_PADDING];
 229 };
 230
 231 #define LTTNG_UST_PROBE_DESC_PADDING    40
 232 struct lttng_probe_desc {
 233         const char *provider;
 234         const struct lttng_event_desc **event_desc;
 235         unsigned int nr_events;
 236         struct cds_list_head head;              /* chain registered probes */
 237         char padding[LTTNG_UST_PROBE_DESC_PADDING];
 238 };
 239
 240 /* Data structures used by the tracer. */
 241
 242 /*
 243  * Entry describing a per-session active wildcard, along with the event
 244  * attribute and channel information configuring the events that need to
 245  * be enabled.
 246  */
 247 struct session_wildcard {
 248         struct ltt_channel *chan;
 249         struct lttng_ctx *ctx;  /* TODO */
 250         struct lttng_ust_event event_param;
 251         struct cds_list_head events;    /* list of events enabled */
 252         struct cds_list_head list;      /* per-session list of wildcards */
 253         struct cds_list_head session_list; /* node of session wildcard list */
 254         struct wildcard_entry *entry;
 255         struct lttng_ust_filter_bytecode *filter_bytecode;
 256         unsigned int enabled:1;
 257 };
 258
 259 /*
 260  * Entry describing an active wildcard (per name) for all sessions.
 261  */
 262 struct wildcard_entry {
 263         /* node of global wildcards list */
 264         struct cds_list_head list;
 265         /* head of session list to which this wildcard apply */
 266         struct cds_list_head session_list;
 267         enum lttng_ust_loglevel_type loglevel_type;
 268         struct lttng_ust_filter_bytecode *filter_bytecode;
 269         int loglevel;
 270         char name[0];
 271 };
 272
 273 struct tp_list_entry {
 274         struct lttng_ust_tracepoint_iter tp;
 275         struct cds_list_head head;
 276 };
 277
 278 struct lttng_ust_tracepoint_list {
 279         struct tp_list_entry *iter;
 280         struct cds_list_head head;
 281 };
 282
 283 struct tp_field_list_entry {
 284         struct lttng_ust_field_iter field;
 285         struct cds_list_head head;
 286 };
 287
 288 struct lttng_ust_field_list {
 289         struct tp_field_list_entry *iter;
 290         struct cds_list_head head;
 291 };
 292
 293 struct ust_pending_probe;
 294 struct ltt_event;
 295 struct lttng_ust_filter_bytecode;
 296
 297 /*
 298  * ltt_event structure is referred to by the tracing fast path. It must be
 299  * kept small.
 300  *
 301  * IMPORTANT: this structure is part of the ABI between the probe and
 302  * UST. Fields need to be only added at the end, never reordered, never
 303  * removed.
 304  */
 305 struct ltt_event {
 306         /* LTTng-UST 2.0 starts here */
 307         unsigned int id;
 308         struct ltt_channel *chan;
 309         int enabled;
 310         const struct lttng_event_desc *desc;
 311         int (*filter)(void *filter_data, const char *filter_stack_data);
 312         struct lttng_ctx *ctx;
 313         enum lttng_ust_instrumentation instrumentation;
 314         union {
 315         } u;
 316         struct cds_list_head list;              /* Event list */
 317         struct cds_list_head wildcard_list;     /* Event list for wildcard */
 318         struct ust_pending_probe *pending_probe;
 319         unsigned int metadata_dumped:1;
 320         /* LTTng-UST 2.1 starts here */
 321         struct lttng_ust_filter_bytecode *filter_bytecode;
 322         void *filter_data;
 323 };
 324
 325 struct channel;
 326 struct lttng_ust_shm_handle;
 327
 328 /*
 329  * IMPORTANT: this structure is part of the ABI between the probe and
 330  * UST. Fields need to be only added at the end, never reordered, never
 331  * removed.
 332  */
 333 struct ltt_channel_ops {
 334         struct ltt_channel *(*channel_create)(const char *name,
 335                                 void *buf_addr,
 336                                 size_t subbuf_size, size_t num_subbuf,
 337                                 unsigned int switch_timer_interval,
 338                                 unsigned int read_timer_interval,
 339                                 int **shm_fd, int **wait_fd,
 340                                 uint64_t **memory_map_size,
 341                                 struct ltt_channel *chan_priv_init);
 342         void (*channel_destroy)(struct ltt_channel *ltt_chan);
 343         struct lttng_ust_lib_ring_buffer *(*buffer_read_open)(struct channel *chan,
 344                                 struct lttng_ust_shm_handle *handle,
 345                                 int **shm_fd, int **wait_fd,
 346                                 uint64_t **memory_map_size);
 347         void (*buffer_read_close)(struct lttng_ust_lib_ring_buffer *buf,
 348                                 struct lttng_ust_shm_handle *handle);
 349         int (*event_reserve)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 350                              uint32_t event_id);
 351         void (*event_commit)(struct lttng_ust_lib_ring_buffer_ctx *ctx);
 352         void (*event_write)(struct lttng_ust_lib_ring_buffer_ctx *ctx, const void *src,
 353                             size_t len);
 354         /*
 355          * packet_avail_size returns the available size in the current
 356          * packet. Note that the size returned is only a hint, since it
 357          * may change due to concurrent writes.
 358          */
 359         size_t (*packet_avail_size)(struct channel *chan,
 360                                     struct lttng_ust_shm_handle *handle);
 361         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 362         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 363         int (*is_finalized)(struct channel *chan);
 364         int (*is_disabled)(struct channel *chan);
 365         int (*flush_buffer)(struct channel *chan, struct lttng_ust_shm_handle *handle);
 366 };
 367
 368 /*
 369  * IMPORTANT: this structure is part of the ABI between the probe and
 370  * UST. Fields need to be only added at the end, never reordered, never
 371  * removed.
 372  */
 373 struct ltt_channel {
 374         /*
 375          * The pointers located in this private data are NOT safe to be
 376          * dereferenced by the consumer. The only operations the
 377          * consumer process is designed to be allowed to do is to read
 378          * and perform subbuffer flush.
 379          */
 380         struct channel *chan;           /* Channel buffers */
 381         int enabled;
 382         struct lttng_ctx *ctx;
 383         /* Event ID management */
 384         struct ltt_session *session;
 385         int objd;                       /* Object associated to channel */
 386         unsigned int free_event_id;     /* Next event ID to allocate */
 387         unsigned int used_event_id;     /* Max allocated event IDs */
 388         struct cds_list_head list;      /* Channel list */
 389         struct ltt_channel_ops *ops;
 390         int header_type;                /* 0: unset, 1: compact, 2: large */
 391         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
 392         unsigned int metadata_dumped:1;
 393
 394         /* Channel ID, available for consumer too */
 395         unsigned int id;
 396         /* Copy of session UUID for consumer (availability through shm) */
 397         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 398 };
 399
 400 /*
 401  * IMPORTANT: this structure is part of the ABI between the probe and
 402  * UST. Fields need to be only added at the end, never reordered, never
 403  * removed.
 404  */
 405 struct ltt_session {
 406         int active;                     /* Is trace session active ? */
 407         int been_active;                /* Has trace session been active ? */
 408         int objd;                       /* Object associated to session */
 409         struct ltt_channel *metadata;   /* Metadata channel */
 410         struct cds_list_head chan;      /* Channel list head */
 411         struct cds_list_head events;    /* Event list head */
 412         struct cds_list_head wildcards; /* Wildcard list head */
 413         struct cds_list_head list;      /* Session list */
 414         unsigned int free_chan_id;      /* Next chan ID to allocate */
 415         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 416         unsigned int metadata_dumped:1;
 417 };
 418
 419 struct ltt_transport {
 420         char *name;
 421         struct cds_list_head node;
 422         struct ltt_channel_ops ops;
 423 };
 424
 425 struct ltt_session *ltt_session_create(void);
 426 int ltt_session_enable(struct ltt_session *session);
 427 int ltt_session_disable(struct ltt_session *session);
 428 void ltt_session_destroy(struct ltt_session *session);
 429
 430 struct ltt_channel *ltt_channel_create(struct ltt_session *session,
 431                                        const char *transport_name,
 432                                        void *buf_addr,
 433                                        size_t subbuf_size, size_t num_subbuf,
 434                                        unsigned int switch_timer_interval,
 435                                        unsigned int read_timer_interval,
 436                                        int **shm_fd, int **wait_fd,
 437                                        uint64_t **memory_map_size,
 438                                        struct ltt_channel *chan_priv_init);
 439 struct ltt_channel *ltt_global_channel_create(struct ltt_session *session,
 440                                        int overwrite, void *buf_addr,
 441                                        size_t subbuf_size, size_t num_subbuf,
 442                                        unsigned int switch_timer_interval,
 443                                        unsigned int read_timer_interval,
 444                                        int **shm_fd, int **wait_fd,
 445                                        uint64_t **memory_map_size);
 446
 447 int ltt_event_create(struct ltt_channel *chan,
 448                 struct lttng_ust_event *event_param,
 449                 struct ltt_event **event);
 450
 451 int ltt_channel_enable(struct ltt_channel *channel);
 452 int ltt_channel_disable(struct ltt_channel *channel);
 453 int ltt_event_enable(struct ltt_event *event);
 454 int ltt_event_disable(struct ltt_event *event);
 455
 456 void ltt_transport_register(struct ltt_transport *transport);
 457 void ltt_transport_unregister(struct ltt_transport *transport);
 458
 459 void synchronize_trace(void);
 460
 461 int ltt_probe_register(struct lttng_probe_desc *desc);
 462 void ltt_probe_unregister(struct lttng_probe_desc *desc);
 463 int pending_probe_fix_events(const struct lttng_event_desc *desc);
 464 const struct lttng_event_desc *ltt_event_get(const char *name);
 465 void ltt_event_put(const struct lttng_event_desc *desc);
 466 int ltt_probes_init(void);
 467 void ltt_probes_exit(void);
 468 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 469 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p);
 470 void lttng_remove_context_field(struct lttng_ctx **ctx_p,
 471                                 struct lttng_ctx_field *field);
 472 void lttng_destroy_context(struct lttng_ctx *ctx);
 473 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 474 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 475 int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
 476 int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
 477 void lttng_context_vtid_reset(void);
 478 void lttng_context_vpid_reset(void);
 479
 480 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
 481 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
 482 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;
 483
 484 struct ltt_transport *ltt_transport_find(const char *name);
 485
 486 int ltt_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
 487 void ltt_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
 488 struct lttng_ust_tracepoint_iter *
 489         lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
 490 int ltt_probes_get_field_list(struct lttng_ust_field_list *list);
 491 void ltt_probes_prune_field_list(struct lttng_ust_field_list *list);
 492 struct lttng_ust_field_iter *
 493         lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list);
 494
 495 int ltt_wildcard_enable(struct session_wildcard *wildcard);
 496 int ltt_wildcard_disable(struct session_wildcard *wildcard);
 497 int ltt_wildcard_create(struct ltt_channel *chan,
 498         struct lttng_ust_event *event_param,
 499         struct session_wildcard **sl);
 500 int ltt_loglevel_match(const struct lttng_event_desc *desc,
 501                 enum lttng_ust_loglevel_type req_type,
 502                 int req_loglevel);
 503 void ltt_probes_create_wildcard_events(struct wildcard_entry *entry,
 504                                 struct session_wildcard *wildcard);
 505 int lttng_filter_event_attach_bytecode(struct ltt_event *event,
 506                 struct lttng_ust_filter_bytecode *filter);
 507 int lttng_filter_wildcard_attach_bytecode(struct session_wildcard *wildcard,
 508                 struct lttng_ust_filter_bytecode *filter);
 509 void lttng_filter_event_link_bytecode(struct ltt_event *event,
 510                 struct lttng_ust_filter_bytecode *filter_bytecode);
 511 void lttng_filter_wildcard_link_bytecode(struct session_wildcard *wildcard);
 512
 513 #endif /* _LTTNG_UST_EVENTS_H */