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