include/ust/lttng-events.h

   1 #ifndef _UST_LTTNG_EVENTS_H
   2 #define _UST_LTTNG_EVENTS_H
   3
   4 /*
   5  * ust/lttng-events.h
   6  *
   7  * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   8  *
   9  * Holds LTTng per-session event registry.
  10  *
  11  * Dual LGPL v2.1/GPL v2 license.
  12  */
  13
  14 #include <urcu/list.h>
  15 #include <uuid/uuid.h>
  16 #include <stdint.h>
  17 #include <ust/lttng-ust-abi.h>
  18 #include <ust/lttng-tracer.h>
  19 #include <endian.h>
  20 #include <float.h>
  21
  22 struct ltt_channel;
  23 struct ltt_session;
  24 struct lib_ring_buffer_ctx;
  25
  26 /* Type description */
  27
  28 /* Update the astract_types name table in lttng-types.c along with this enum */
  29 enum abstract_types {
  30         atype_integer,
  31         atype_enum,
  32         atype_array,
  33         atype_sequence,
  34         atype_string,
  35         atype_float,
  36         NR_ABSTRACT_TYPES,
  37 };
  38
  39 /* Update the string_encodings name table in lttng-types.c along with this enum */
  40 enum lttng_string_encodings {
  41         lttng_encode_none = 0,
  42         lttng_encode_UTF8 = 1,
  43         lttng_encode_ASCII = 2,
  44         NR_STRING_ENCODINGS,
  45 };
  46
  47 struct lttng_enum_entry {
  48         unsigned long long start, end;  /* start and end are inclusive */
  49         const char *string;
  50 };
  51
  52 #define __type_integer(_type, _byte_order, _base, _encoding)    \
  53         {                                                       \
  54             .atype = atype_integer,                             \
  55             .u.basic.integer =                                  \
  56                 {                                               \
  57                   .size = sizeof(_type) * CHAR_BIT,             \
  58                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
  59                   .signedness = lttng_is_signed_type(_type),    \
  60                   .reverse_byte_order = _byte_order != __BYTE_ORDER,    \
  61                   .base = _base,                                \
  62                   .encoding = lttng_encode_##_encoding,         \
  63                 },                                              \
  64         }                                                       \
  65
  66 struct lttng_integer_type {
  67         unsigned int size;              /* in bits */
  68         unsigned short alignment;       /* in bits */
  69         unsigned int signedness:1;
  70         unsigned int reverse_byte_order:1;
  71         unsigned int base;              /* 2, 8, 10, 16, for pretty print */
  72         enum lttng_string_encodings encoding;
  73 };
  74
  75 /*
  76  * Only float and double are supported. long double is not supported at
  77  * the moment.
  78  */
  79 #define _float_mant_dig(_type)                                          \
  80         (sizeof(_type) == sizeof(float) ? FLT_MANT_DIG                  \
  81                 : (sizeof(_type) == sizeof(double) ? DBL_MANT_DIG       \
  82                 : 0))
  83
  84 #define __type_float(_type)                                     \
  85         {                                                       \
  86             .atype = atype_float,                               \
  87             .u.basic._float =                                   \
  88                 {                                               \
  89                   .exp_dig = sizeof(_type) * CHAR_BIT           \
  90                                 - _float_mant_dig(_type),       \
  91                   .mant_dig = _float_mant_dig(_type),           \
  92                   .alignment = lttng_alignof(_type) * CHAR_BIT, \
  93                   .reverse_byte_order = __BYTE_ORDER != __FLOAT_WORD_ORDER, \
  94                 },                                              \
  95         }                                                       \
  96
  97 struct lttng_float_type {
  98         unsigned int exp_dig;           /* exponent digits, in bits */
  99         unsigned int mant_dig;          /* mantissa digits, in bits */
 100         unsigned short alignment;       /* in bits */
 101         unsigned int reverse_byte_order:1;
 102 };
 103
 104 union _lttng_basic_type {
 105         struct lttng_integer_type integer;
 106         struct {
 107                 const char *name;
 108         } enumeration;
 109         struct {
 110                 enum lttng_string_encodings encoding;
 111         } string;
 112         struct lttng_float_type _float;
 113 };
 114
 115 struct lttng_basic_type {
 116         enum abstract_types atype;
 117         union {
 118                 union _lttng_basic_type basic;
 119         } u;
 120 };
 121
 122 struct lttng_type {
 123         enum abstract_types atype;
 124         union {
 125                 union _lttng_basic_type basic;
 126                 struct {
 127                         struct lttng_basic_type elem_type;
 128                         unsigned int length;            /* num. elems. */
 129                 } array;
 130                 struct {
 131                         struct lttng_basic_type length_type;
 132                         struct lttng_basic_type elem_type;
 133                 } sequence;
 134         } u;
 135 };
 136
 137 struct lttng_enum {
 138         const char *name;
 139         struct lttng_type container_type;
 140         const struct lttng_enum_entry *entries;
 141         unsigned int len;
 142 };
 143
 144 /* Event field description */
 145
 146 struct lttng_event_field {
 147         const char *name;
 148         struct lttng_type type;
 149 };
 150
 151 struct lttng_ctx_field {
 152         struct lttng_event_field event_field;
 153         size_t (*get_size)(size_t offset);
 154         void (*record)(struct lttng_ctx_field *field,
 155                        struct lib_ring_buffer_ctx *ctx,
 156                        struct ltt_channel *chan);
 157         union {
 158         } u;
 159         void (*destroy)(struct lttng_ctx_field *field);
 160 };
 161
 162 struct lttng_ctx {
 163         struct lttng_ctx_field *fields;
 164         unsigned int nr_fields;
 165         unsigned int allocated_fields;
 166 };
 167
 168 struct lttng_event_desc {
 169         const char *name;
 170         void *probe_callback;
 171         const struct lttng_event_ctx *ctx;      /* context */
 172         const struct lttng_event_field *fields; /* event payload */
 173         unsigned int nr_fields;
 174 };
 175
 176 struct lttng_probe_desc {
 177         const struct lttng_event_desc *event_desc;
 178         unsigned int nr_events;
 179         struct cds_list_head head;              /* chain registered probes */
 180 };
 181
 182 struct ust_pending_probe;
 183
 184 /*
 185  * ltt_event structure is referred to by the tracing fast path. It must be
 186  * kept small.
 187  */
 188 struct ltt_event {
 189         unsigned int id;
 190         struct ltt_channel *chan;
 191         int enabled;
 192         const struct lttng_event_desc *desc;
 193         void *filter;
 194         struct lttng_ctx *ctx;
 195         enum lttng_ust_instrumentation instrumentation;
 196         union {
 197         } u;
 198         struct cds_list_head list;              /* Event list */
 199         struct ust_pending_probe *pending_probe;
 200         int metadata_dumped:1;
 201 };
 202
 203 struct channel;
 204 struct shm_handle;
 205
 206 struct ltt_channel_ops {
 207         struct ltt_channel *(*channel_create)(const char *name,
 208                                 struct ltt_channel *ltt_chan,
 209                                 void *buf_addr,
 210                                 size_t subbuf_size, size_t num_subbuf,
 211                                 unsigned int switch_timer_interval,
 212                                 unsigned int read_timer_interval,
 213                                 int *shm_fd, int *wait_fd,
 214                                 uint64_t *memory_map_size);
 215         void (*channel_destroy)(struct ltt_channel *ltt_chan);
 216         struct lib_ring_buffer *(*buffer_read_open)(struct channel *chan,
 217                                 struct shm_handle *handle,
 218                                 int *shm_fd, int *wait_fd,
 219                                 uint64_t *memory_map_size);
 220         void (*buffer_read_close)(struct lib_ring_buffer *buf,
 221                                 struct shm_handle *handle);
 222         int (*event_reserve)(struct lib_ring_buffer_ctx *ctx,
 223                              uint32_t event_id);
 224         void (*event_commit)(struct lib_ring_buffer_ctx *ctx);
 225         void (*event_write)(struct lib_ring_buffer_ctx *ctx, const void *src,
 226                             size_t len);
 227         /*
 228          * packet_avail_size returns the available size in the current
 229          * packet. Note that the size returned is only a hint, since it
 230          * may change due to concurrent writes.
 231          */
 232         size_t (*packet_avail_size)(struct channel *chan,
 233                                     struct shm_handle *handle);
 234         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 235         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 236         int (*is_finalized)(struct channel *chan);
 237         int (*is_disabled)(struct channel *chan);
 238 };
 239
 240 struct ltt_channel {
 241         unsigned int id;
 242         struct channel *chan;           /* Channel buffers */
 243         int enabled;
 244         struct lttng_ctx *ctx;
 245         /* Event ID management */
 246         struct ltt_session *session;
 247         int objd;                       /* Object associated to channel */
 248         unsigned int free_event_id;     /* Next event ID to allocate */
 249         unsigned int used_event_id;     /* Max allocated event IDs */
 250         struct cds_list_head list;      /* Channel list */
 251         struct ltt_channel_ops *ops;
 252         int header_type;                /* 0: unset, 1: compact, 2: large */
 253         struct shm_handle *handle;      /* shared-memory handle */
 254         int metadata_dumped:1;
 255 };
 256
 257 struct ltt_session {
 258         int active;                     /* Is trace session active ? */
 259         int been_active;                /* Has trace session been active ? */
 260         int objd;                       /* Object associated to session */
 261         struct ltt_channel *metadata;   /* Metadata channel */
 262         struct cds_list_head chan;      /* Channel list head */
 263         struct cds_list_head events;    /* Event list head */
 264         struct cds_list_head list;      /* Session list */
 265         unsigned int free_chan_id;      /* Next chan ID to allocate */
 266         uuid_t uuid;                    /* Trace session unique ID */
 267         int metadata_dumped:1;
 268 };
 269
 270 struct ltt_transport {
 271         char *name;
 272         struct cds_list_head node;
 273         struct ltt_channel_ops ops;
 274 };
 275
 276 struct ltt_session *ltt_session_create(void);
 277 int ltt_session_enable(struct ltt_session *session);
 278 int ltt_session_disable(struct ltt_session *session);
 279 void ltt_session_destroy(struct ltt_session *session);
 280
 281 struct ltt_channel *ltt_channel_create(struct ltt_session *session,
 282                                        const char *transport_name,
 283                                        void *buf_addr,
 284                                        size_t subbuf_size, size_t num_subbuf,
 285                                        unsigned int switch_timer_interval,
 286                                        unsigned int read_timer_interval,
 287                                        int *shm_fd, int *wait_fd,
 288                                        uint64_t *memory_map_size);
 289 struct ltt_channel *ltt_global_channel_create(struct ltt_session *session,
 290                                        int overwrite, void *buf_addr,
 291                                        size_t subbuf_size, size_t num_subbuf,
 292                                        unsigned int switch_timer_interval,
 293                                        unsigned int read_timer_interval,
 294                                        int *shm_fd, int *wait_fd,
 295                                        uint64_t *memory_map_size);
 296
 297 struct ltt_event *ltt_event_create(struct ltt_channel *chan,
 298                                    struct lttng_ust_event *event_param,
 299                                    void *filter);
 300
 301 int ltt_channel_enable(struct ltt_channel *channel);
 302 int ltt_channel_disable(struct ltt_channel *channel);
 303 int ltt_event_enable(struct ltt_event *event);
 304 int ltt_event_disable(struct ltt_event *event);
 305
 306 void ltt_transport_register(struct ltt_transport *transport);
 307 void ltt_transport_unregister(struct ltt_transport *transport);
 308
 309 void synchronize_trace(void);
 310
 311 int ltt_probe_register(struct lttng_probe_desc *desc);
 312 void ltt_probe_unregister(struct lttng_probe_desc *desc);
 313 int pending_probe_fix_events(const struct lttng_event_desc *desc);
 314 const struct lttng_event_desc *ltt_event_get(const char *name);
 315 void ltt_event_put(const struct lttng_event_desc *desc);
 316 int ltt_probes_init(void);
 317 void ltt_probes_exit(void);
 318 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 319 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p);
 320 void lttng_remove_context_field(struct lttng_ctx **ctx_p,
 321                                 struct lttng_ctx_field *field);
 322 void lttng_destroy_context(struct lttng_ctx *ctx);
 323 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 324 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 325 int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
 326 void lttng_context_vtid_reset(void);
 327 void lttng_context_vpid_reset(void);
 328
 329 #endif /* _UST_LTTNG_EVENTS_H */