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