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