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 <endian.h>
  19 #include <float.h>
  20
  21 #undef is_signed_type
  22 #define is_signed_type(type)            (((type)(-1)) < 0)
  23
  24 struct ltt_channel;
  25 struct ltt_session;
  26 struct lib_ring_buffer_ctx;
  27
  28 /* Type description */
  29
  30 /* Update the astract_types name table in lttng-types.c along with this enum */
  31 enum abstract_types {
  32         atype_integer,
  33         atype_enum,
  34         atype_array,
  35         atype_sequence,
  36         atype_string,
  37         atype_float,
  38         NR_ABSTRACT_TYPES,
  39 };
  40
  41 /* Update the string_encodings name table in lttng-types.c along with this enum */
  42 enum lttng_string_encodings {
  43         lttng_encode_none = 0,
  44         lttng_encode_UTF8 = 1,
  45         lttng_encode_ASCII = 2,
  46         NR_STRING_ENCODINGS,
  47 };
  48
  49 struct lttng_enum_entry {
  50         unsigned long long start, end;  /* start and end are inclusive */
  51         const char *string;
  52 };
  53
  54 #define __type_integer(_type, _byte_order, _base, _encoding)    \
  55         {                                                       \
  56             .atype = atype_integer,                             \
  57             .u.basic.integer =                                  \
  58                 {                                               \
  59                   .size = sizeof(_type) * CHAR_BIT,             \
  60                   .alignment = ltt_alignof(_type) * CHAR_BIT,   \
  61                   .signedness = is_signed_type(_type),          \
  62                   .reverse_byte_order = _byte_order != __BYTE_ORDER,    \
  63                   .base = _base,                                \
  64                   .encoding = lttng_encode_##_encoding,         \
  65                 },                                              \
  66         }                                                       \
  67
  68 struct lttng_integer_type {
  69         unsigned int size;              /* in bits */
  70         unsigned short alignment;       /* in bits */
  71         unsigned int signedness:1;
  72         unsigned int reverse_byte_order:1;
  73         unsigned int base;              /* 2, 8, 10, 16, for pretty print */
  74         enum lttng_string_encodings encoding;
  75 };
  76
  77 #define _float_mant_dig(_type)                                          \
  78         (sizeof(_type) == sizeof(float) ? FLT_MANT_DIG                  \
  79                 : (sizeof(_type) == sizeof(double) ? DBL_MANT_DIG       \
  80                 : (sizeof(_type) == sizeof(long double) ? LDBL_MANT_DIG \
  81                 : 0)))
  82
  83 #define __type_float(_type)                                     \
  84         {                                                       \
  85             .atype = atype_float,                               \
  86             .u.basic._float =                                   \
  87                 {                                               \
  88                   .exp_dig = sizeof(_type) * CHAR_BIT           \
  89                                 - _float_mant_dig(_type),       \
  90                   .mant_dig = _float_mant_dig(_type),           \
  91                   .alignment = ltt_alignof(_type) * CHAR_BIT,   \
  92                   .signedness = is_signed_type(_type),          \
  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 /*
 183  * ltt_event structure is referred to by the tracing fast path. It must be
 184  * kept small.
 185  */
 186 struct ltt_event {
 187         unsigned int id;
 188         struct ltt_channel *chan;
 189         int enabled;
 190         const struct lttng_event_desc *desc;
 191         void *filter;
 192         struct lttng_ctx *ctx;
 193         enum lttng_ust_instrumentation instrumentation;
 194         union {
 195         } u;
 196         struct cds_list_head list;              /* Event list */
 197         int metadata_dumped:1;
 198 };
 199
 200 struct ltt_channel_ops {
 201         struct channel *(*channel_create)(const char *name,
 202                                 struct ltt_channel *ltt_chan,
 203                                 void *buf_addr,
 204                                 size_t subbuf_size, size_t num_subbuf,
 205                                 unsigned int switch_timer_interval,
 206                                 unsigned int read_timer_interval,
 207                                 int *shmid);
 208         void (*channel_destroy)(struct channel *chan);
 209         struct lib_ring_buffer *(*buffer_read_open)(struct channel *chan);
 210         void (*buffer_read_close)(struct lib_ring_buffer *buf);
 211         int (*event_reserve)(struct lib_ring_buffer_ctx *ctx,
 212                              uint32_t event_id);
 213         void (*event_commit)(struct lib_ring_buffer_ctx *ctx);
 214         void (*event_write)(struct lib_ring_buffer_ctx *ctx, const void *src,
 215                             size_t len);
 216         /*
 217          * packet_avail_size returns the available size in the current
 218          * packet. Note that the size returned is only a hint, since it
 219          * may change due to concurrent writes.
 220          */
 221         size_t (*packet_avail_size)(struct channel *chan);
 222         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 223         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 224         int (*is_finalized)(struct channel *chan);
 225         int (*is_disabled)(struct channel *chan);
 226 };
 227
 228 struct ltt_channel {
 229         unsigned int id;
 230         struct channel *chan;           /* Channel buffers */
 231         int enabled;
 232         struct lttng_ctx *ctx;
 233         /* Event ID management */
 234         struct ltt_session *session;
 235         int objd;                       /* Object associated to channel */
 236         unsigned int free_event_id;     /* Next event ID to allocate */
 237         struct cds_list_head list;      /* Channel list */
 238         struct ltt_channel_ops *ops;
 239         int header_type;                /* 0: unset, 1: compact, 2: large */
 240         int shmfd;                      /* shared-memory file descriptor */
 241         int metadata_dumped:1;
 242 };
 243
 244 struct ltt_session {
 245         int active;                     /* Is trace session active ? */
 246         int been_active;                /* Has trace session been active ? */
 247         int objd;                       /* Object associated to session */
 248         struct ltt_channel *metadata;   /* Metadata channel */
 249         struct cds_list_head chan;      /* Channel list head */
 250         struct cds_list_head events;    /* Event list head */
 251         struct cds_list_head list;      /* Session list */
 252         unsigned int free_chan_id;      /* Next chan ID to allocate */
 253         uuid_t uuid;                    /* Trace session unique ID */
 254         int metadata_dumped:1;
 255 };
 256
 257 struct ltt_transport {
 258         char *name;
 259         struct cds_list_head node;
 260         struct ltt_channel_ops ops;
 261 };
 262
 263 struct ltt_session *ltt_session_create(void);
 264 int ltt_session_enable(struct ltt_session *session);
 265 int ltt_session_disable(struct ltt_session *session);
 266 void ltt_session_destroy(struct ltt_session *session);
 267
 268 struct ltt_channel *ltt_channel_create(struct ltt_session *session,
 269                                        const char *transport_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 struct ltt_channel *ltt_global_channel_create(struct ltt_session *session,
 275                                        int overwrite, void *buf_addr,
 276                                        size_t subbuf_size, size_t num_subbuf,
 277                                        unsigned int switch_timer_interval,
 278                                        unsigned int read_timer_interval);
 279
 280 struct ltt_event *ltt_event_create(struct ltt_channel *chan,
 281                                    struct lttng_ust_event *event_param,
 282                                    void *filter);
 283
 284 int ltt_channel_enable(struct ltt_channel *channel);
 285 int ltt_channel_disable(struct ltt_channel *channel);
 286 int ltt_event_enable(struct ltt_event *event);
 287 int ltt_event_disable(struct ltt_event *event);
 288
 289 void ltt_transport_register(struct ltt_transport *transport);
 290 void ltt_transport_unregister(struct ltt_transport *transport);
 291
 292 void synchronize_trace(void);
 293 //int ltt_debugfs_abi_init(void);
 294 //void ltt_debugfs_abi_exit(void);
 295
 296 int ltt_probe_register(struct lttng_probe_desc *desc);
 297 void ltt_probe_unregister(struct lttng_probe_desc *desc);
 298 const struct lttng_event_desc *ltt_event_get(const char *name);
 299 void ltt_event_put(const struct lttng_event_desc *desc);
 300 int ltt_probes_init(void);
 301 void ltt_probes_exit(void);
 302 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx);
 303 void lttng_remove_context_field(struct lttng_ctx **ctx,
 304                                 struct lttng_ctx_field *field);
 305 void lttng_destroy_context(struct lttng_ctx *ctx);
 306 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 307
 308 //extern const struct file_operations lttng_tracepoint_list_fops;
 309
 310 #endif /* _UST_LTTNG_EVENTS_H */