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 /* Event field description */
 183
 184 #define LTTNG_UST_EVENT_FIELD_PADDING   32
 185 struct lttng_event_field {
 186         const char *name;
 187         struct lttng_type type;
 188         char padding[LTTNG_UST_EVENT_FIELD_PADDING];
 189 };
 190
 191 #define LTTNG_UST_CTX_FIELD_PADDING     40
 192 struct lttng_ctx_field {
 193         struct lttng_event_field event_field;
 194         size_t (*get_size)(size_t offset);
 195         void (*record)(struct lttng_ctx_field *field,
 196                        struct lttng_ust_lib_ring_buffer_ctx *ctx,
 197                        struct ltt_channel *chan);
 198         union {
 199                 char padding[LTTNG_UST_CTX_FIELD_PADDING];
 200         } u;
 201         void (*destroy)(struct lttng_ctx_field *field);
 202 };
 203
 204 #define LTTNG_UST_CTX_PADDING   24
 205 struct lttng_ctx {
 206         struct lttng_ctx_field *fields;
 207         unsigned int nr_fields;
 208         unsigned int allocated_fields;
 209         char padding[LTTNG_UST_CTX_PADDING];
 210 };
 211
 212 #define LTTNG_UST_EVENT_DESC_PADDING    40
 213 struct lttng_event_desc {
 214         const char *name;
 215         void (*probe_callback)(void);
 216         const struct lttng_event_ctx *ctx;      /* context */
 217         const struct lttng_event_field *fields; /* event payload */
 218         unsigned int nr_fields;
 219         const int **loglevel;
 220         const char *signature;  /* Argument types/names received */
 221         char padding[LTTNG_UST_EVENT_DESC_PADDING];
 222 };
 223
 224 #define LTTNG_UST_PROBE_DESC_PADDING    40
 225 struct lttng_probe_desc {
 226         const char *provider;
 227         const struct lttng_event_desc **event_desc;
 228         unsigned int nr_events;
 229         struct cds_list_head head;              /* chain registered probes */
 230         char padding[LTTNG_UST_PROBE_DESC_PADDING];
 231 };
 232
 233 /* Data structures used by the tracer. */
 234
 235 /*
 236  * Entry describing a per-session active wildcard, along with the event
 237  * attribute and channel information configuring the events that need to
 238  * be enabled.
 239  */
 240 struct session_wildcard {
 241         struct ltt_channel *chan;
 242         struct lttng_ctx *ctx;  /* TODO */
 243         struct lttng_ust_event event_param;
 244         struct cds_list_head events;    /* list of events enabled */
 245         struct cds_list_head list;      /* per-session list of wildcards */
 246         struct cds_list_head session_list; /* node of session wildcard list */
 247         struct wildcard_entry *entry;
 248         struct lttng_ust_filter_bytecode *filter_bytecode;
 249         unsigned int enabled:1;
 250 };
 251
 252 /*
 253  * Entry describing an active wildcard (per name) for all sessions.
 254  */
 255 struct wildcard_entry {
 256         /* node of global wildcards list */
 257         struct cds_list_head list;
 258         /* head of session list to which this wildcard apply */
 259         struct cds_list_head session_list;
 260         enum lttng_ust_loglevel_type loglevel_type;
 261         struct lttng_ust_filter_bytecode *filter_bytecode;
 262         int loglevel;
 263         char name[0];
 264 };
 265
 266 struct tp_list_entry {
 267         struct lttng_ust_tracepoint_iter tp;
 268         struct cds_list_head head;
 269 };
 270
 271 struct lttng_ust_tracepoint_list {
 272         struct tp_list_entry *iter;
 273         struct cds_list_head head;
 274 };
 275
 276 struct tp_field_list_entry {
 277         struct lttng_ust_field_iter field;
 278         struct cds_list_head head;
 279 };
 280
 281 struct lttng_ust_field_list {
 282         struct tp_field_list_entry *iter;
 283         struct cds_list_head head;
 284 };
 285
 286 struct ust_pending_probe;
 287 struct ltt_event;
 288 struct lttng_ust_filter_bytecode;
 289
 290 /*
 291  * ltt_event structure is referred to by the tracing fast path. It must be
 292  * kept small.
 293  */
 294 struct ltt_event {
 295         unsigned int id;
 296         struct ltt_channel *chan;
 297         int enabled;
 298         const struct lttng_event_desc *desc;
 299         int (*filter)(void *filter_data, const char *filter_stack_data);
 300         void *filter_data;
 301         struct lttng_ctx *ctx;
 302         enum lttng_ust_instrumentation instrumentation;
 303         union {
 304         } u;
 305         struct cds_list_head list;              /* Event list */
 306         struct cds_list_head wildcard_list;     /* Event list for wildcard */
 307         struct ust_pending_probe *pending_probe;
 308         struct lttng_ust_filter_bytecode *filter_bytecode;
 309         unsigned int metadata_dumped:1;
 310 };
 311
 312 struct channel;
 313 struct lttng_ust_shm_handle;
 314
 315 struct ltt_channel_ops {
 316         struct ltt_channel *(*channel_create)(const char *name,
 317                                 void *buf_addr,
 318                                 size_t subbuf_size, size_t num_subbuf,
 319                                 unsigned int switch_timer_interval,
 320                                 unsigned int read_timer_interval,
 321                                 int **shm_fd, int **wait_fd,
 322                                 uint64_t **memory_map_size,
 323                                 struct ltt_channel *chan_priv_init);
 324         void (*channel_destroy)(struct ltt_channel *ltt_chan);
 325         struct lttng_ust_lib_ring_buffer *(*buffer_read_open)(struct channel *chan,
 326                                 struct lttng_ust_shm_handle *handle,
 327                                 int **shm_fd, int **wait_fd,
 328                                 uint64_t **memory_map_size);
 329         void (*buffer_read_close)(struct lttng_ust_lib_ring_buffer *buf,
 330                                 struct lttng_ust_shm_handle *handle);
 331         int (*event_reserve)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
 332                              uint32_t event_id);
 333         void (*event_commit)(struct lttng_ust_lib_ring_buffer_ctx *ctx);
 334         void (*event_write)(struct lttng_ust_lib_ring_buffer_ctx *ctx, const void *src,
 335                             size_t len);
 336         /*
 337          * packet_avail_size returns the available size in the current
 338          * packet. Note that the size returned is only a hint, since it
 339          * may change due to concurrent writes.
 340          */
 341         size_t (*packet_avail_size)(struct channel *chan,
 342                                     struct lttng_ust_shm_handle *handle);
 343         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 344         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 345         int (*is_finalized)(struct channel *chan);
 346         int (*is_disabled)(struct channel *chan);
 347         int (*flush_buffer)(struct channel *chan, struct lttng_ust_shm_handle *handle);
 348 };
 349
 350 struct ltt_channel {
 351         /*
 352          * The pointers located in this private data are NOT safe to be
 353          * dereferenced by the consumer. The only operations the
 354          * consumer process is designed to be allowed to do is to read
 355          * and perform subbuffer flush.
 356          */
 357         struct channel *chan;           /* Channel buffers */
 358         int enabled;
 359         struct lttng_ctx *ctx;
 360         /* Event ID management */
 361         struct ltt_session *session;
 362         int objd;                       /* Object associated to channel */
 363         unsigned int free_event_id;     /* Next event ID to allocate */
 364         unsigned int used_event_id;     /* Max allocated event IDs */
 365         struct cds_list_head list;      /* Channel list */
 366         struct ltt_channel_ops *ops;
 367         int header_type;                /* 0: unset, 1: compact, 2: large */
 368         struct lttng_ust_shm_handle *handle;    /* shared-memory handle */
 369         unsigned int metadata_dumped:1;
 370
 371         /* Channel ID, available for consumer too */
 372         unsigned int id;
 373         /* Copy of session UUID for consumer (availability through shm) */
 374         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 375 };
 376
 377 struct ltt_session {
 378         int active;                     /* Is trace session active ? */
 379         int been_active;                /* Has trace session been active ? */
 380         int objd;                       /* Object associated to session */
 381         struct ltt_channel *metadata;   /* Metadata channel */
 382         struct cds_list_head chan;      /* Channel list head */
 383         struct cds_list_head events;    /* Event list head */
 384         struct cds_list_head wildcards; /* Wildcard list head */
 385         struct cds_list_head list;      /* Session list */
 386         unsigned int free_chan_id;      /* Next chan ID to allocate */
 387         unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
 388         unsigned int metadata_dumped:1;
 389 };
 390
 391 struct ltt_transport {
 392         char *name;
 393         struct cds_list_head node;
 394         struct ltt_channel_ops ops;
 395 };
 396
 397 struct ltt_session *ltt_session_create(void);
 398 int ltt_session_enable(struct ltt_session *session);
 399 int ltt_session_disable(struct ltt_session *session);
 400 void ltt_session_destroy(struct ltt_session *session);
 401
 402 struct ltt_channel *ltt_channel_create(struct ltt_session *session,
 403                                        const char *transport_name,
 404                                        void *buf_addr,
 405                                        size_t subbuf_size, size_t num_subbuf,
 406                                        unsigned int switch_timer_interval,
 407                                        unsigned int read_timer_interval,
 408                                        int **shm_fd, int **wait_fd,
 409                                        uint64_t **memory_map_size,
 410                                        struct ltt_channel *chan_priv_init);
 411 struct ltt_channel *ltt_global_channel_create(struct ltt_session *session,
 412                                        int overwrite, void *buf_addr,
 413                                        size_t subbuf_size, size_t num_subbuf,
 414                                        unsigned int switch_timer_interval,
 415                                        unsigned int read_timer_interval,
 416                                        int **shm_fd, int **wait_fd,
 417                                        uint64_t **memory_map_size);
 418
 419 int ltt_event_create(struct ltt_channel *chan,
 420                 struct lttng_ust_event *event_param,
 421                 struct ltt_event **event);
 422
 423 int ltt_channel_enable(struct ltt_channel *channel);
 424 int ltt_channel_disable(struct ltt_channel *channel);
 425 int ltt_event_enable(struct ltt_event *event);
 426 int ltt_event_disable(struct ltt_event *event);
 427
 428 void ltt_transport_register(struct ltt_transport *transport);
 429 void ltt_transport_unregister(struct ltt_transport *transport);
 430
 431 void synchronize_trace(void);
 432
 433 int ltt_probe_register(struct lttng_probe_desc *desc);
 434 void ltt_probe_unregister(struct lttng_probe_desc *desc);
 435 int pending_probe_fix_events(const struct lttng_event_desc *desc);
 436 const struct lttng_event_desc *ltt_event_get(const char *name);
 437 void ltt_event_put(const struct lttng_event_desc *desc);
 438 int ltt_probes_init(void);
 439 void ltt_probes_exit(void);
 440 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 441 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p);
 442 void lttng_remove_context_field(struct lttng_ctx **ctx_p,
 443                                 struct lttng_ctx_field *field);
 444 void lttng_destroy_context(struct lttng_ctx *ctx);
 445 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 446 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 447 int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
 448 int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
 449 void lttng_context_vtid_reset(void);
 450 void lttng_context_vpid_reset(void);
 451
 452 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
 453 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
 454 extern const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;
 455
 456 struct ltt_transport *ltt_transport_find(const char *name);
 457
 458 int ltt_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
 459 void ltt_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
 460 struct lttng_ust_tracepoint_iter *
 461         lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
 462 int ltt_probes_get_field_list(struct lttng_ust_field_list *list);
 463 void ltt_probes_prune_field_list(struct lttng_ust_field_list *list);
 464 struct lttng_ust_field_iter *
 465         lttng_ust_field_list_get_iter_next(struct lttng_ust_field_list *list);
 466
 467 int ltt_wildcard_enable(struct session_wildcard *wildcard);
 468 int ltt_wildcard_disable(struct session_wildcard *wildcard);
 469 int ltt_wildcard_create(struct ltt_channel *chan,
 470         struct lttng_ust_event *event_param,
 471         struct session_wildcard **sl);
 472 int ltt_loglevel_match(const struct lttng_event_desc *desc,
 473                 enum lttng_ust_loglevel_type req_type,
 474                 int req_loglevel);
 475 void ltt_probes_create_wildcard_events(struct wildcard_entry *entry,
 476                                 struct session_wildcard *wildcard);
 477 int lttng_filter_event_attach_bytecode(struct ltt_event *event,
 478                 struct lttng_ust_filter_bytecode *filter);
 479 int lttng_filter_wildcard_attach_bytecode(struct session_wildcard *wildcard,
 480                 struct lttng_ust_filter_bytecode *filter);
 481 void lttng_filter_event_link_bytecode(struct ltt_event *event,
 482                 struct lttng_ust_filter_bytecode *filter_bytecode);
 483 void lttng_filter_wildcard_link_bytecode(struct session_wildcard *wildcard);
 484
 485 #endif /* _LTTNG_UST_EVENTS_H */