libust/ltt-events.h

   1 #ifndef _LTT_EVENTS_H
   2 #define _LTT_EVENTS_H
   3
   4 /*
   5  * ltt-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
  19 #undef is_signed_type
  20 #define is_signed_type(type)            (((type)(-1)) < 0)
  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         NR_ABSTRACT_TYPES,
  36 };
  37
  38 /* Update the string_encodings name table in lttng-types.c along with this enum */
  39 enum lttng_string_encodings {
  40         lttng_encode_none = 0,
  41         lttng_encode_UTF8 = 1,
  42         lttng_encode_ASCII = 2,
  43         NR_STRING_ENCODINGS,
  44 };
  45
  46 struct lttng_enum_entry {
  47         unsigned long long start, end;  /* start and end are inclusive */
  48         const char *string;
  49 };
  50
  51 #define __type_integer(_type, _byte_order, _base, _encoding)    \
  52         {                                                       \
  53             .atype = atype_integer,                             \
  54             .u.basic.integer =                                  \
  55                 {                                               \
  56                   .size = sizeof(_type) * CHAR_BIT,             \
  57                   .alignment = ltt_alignof(_type) * CHAR_BIT,   \
  58                   .signedness = is_signed_type(_type),          \
  59                   .reverse_byte_order = _byte_order != __BYTE_ORDER,    \
  60                   .base = _base,                                \
  61                   .encoding = lttng_encode_##_encoding,         \
  62                 },                                              \
  63         }                                                       \
  64
  65 struct lttng_integer_type {
  66         unsigned int size;              /* in bits */
  67         unsigned short alignment;       /* in bits */
  68         unsigned int signedness:1;
  69         unsigned int reverse_byte_order:1;
  70         unsigned int base;              /* 2, 8, 10, 16, for pretty print */
  71         enum lttng_string_encodings encoding;
  72 };
  73
  74 union _lttng_basic_type {
  75         struct lttng_integer_type integer;
  76         struct {
  77                 const char *name;
  78         } enumeration;
  79         struct {
  80                 enum lttng_string_encodings encoding;
  81         } string;
  82 };
  83
  84 struct lttng_basic_type {
  85         enum abstract_types atype;
  86         union {
  87                 union _lttng_basic_type basic;
  88         } u;
  89 };
  90
  91 struct lttng_type {
  92         enum abstract_types atype;
  93         union {
  94                 union _lttng_basic_type basic;
  95                 struct {
  96                         struct lttng_basic_type elem_type;
  97                         unsigned int length;            /* num. elems. */
  98                 } array;
  99                 struct {
 100                         struct lttng_basic_type length_type;
 101                         struct lttng_basic_type elem_type;
 102                 } sequence;
 103         } u;
 104 };
 105
 106 struct lttng_enum {
 107         const char *name;
 108         struct lttng_type container_type;
 109         const struct lttng_enum_entry *entries;
 110         unsigned int len;
 111 };
 112
 113 /* Event field description */
 114
 115 struct lttng_event_field {
 116         const char *name;
 117         struct lttng_type type;
 118 };
 119
 120 struct lttng_ctx_field {
 121         struct lttng_event_field event_field;
 122         size_t (*get_size)(size_t offset);
 123         void (*record)(struct lttng_ctx_field *field,
 124                        struct lib_ring_buffer_ctx *ctx,
 125                        struct ltt_channel *chan);
 126         union {
 127         } u;
 128         void (*destroy)(struct lttng_ctx_field *field);
 129 };
 130
 131 struct lttng_ctx {
 132         struct lttng_ctx_field *fields;
 133         unsigned int nr_fields;
 134         unsigned int allocated_fields;
 135 };
 136
 137 struct lttng_event_desc {
 138         const char *name;
 139         void *probe_callback;
 140         const struct lttng_event_ctx *ctx;      /* context */
 141         const struct lttng_event_field *fields; /* event payload */
 142         unsigned int nr_fields;
 143 };
 144
 145 struct lttng_probe_desc {
 146         const struct lttng_event_desc *event_desc;
 147         unsigned int nr_events;
 148         struct cds_list_head head;              /* chain registered probes */
 149 };
 150
 151 /*
 152  * ltt_event structure is referred to by the tracing fast path. It must be
 153  * kept small.
 154  */
 155 struct ltt_event {
 156         unsigned int id;
 157         struct ltt_channel *chan;
 158         int enabled;
 159         const struct lttng_event_desc *desc;
 160         void *filter;
 161         struct lttng_ctx *ctx;
 162         enum lttng_ust_instrumentation instrumentation;
 163         union {
 164         } u;
 165         struct cds_list_head list;              /* Event list */
 166         int metadata_dumped:1;
 167 };
 168
 169 struct ltt_channel_ops {
 170         struct channel *(*channel_create)(const char *name,
 171                                 struct ltt_channel *ltt_chan,
 172                                 void *buf_addr,
 173                                 size_t subbuf_size, size_t num_subbuf,
 174                                 unsigned int switch_timer_interval,
 175                                 unsigned int read_timer_interval,
 176                                 int *shmid);
 177         void (*channel_destroy)(struct channel *chan);
 178         struct lib_ring_buffer *(*buffer_read_open)(struct channel *chan);
 179         void (*buffer_read_close)(struct lib_ring_buffer *buf);
 180         int (*event_reserve)(struct lib_ring_buffer_ctx *ctx,
 181                              uint32_t event_id);
 182         void (*event_commit)(struct lib_ring_buffer_ctx *ctx);
 183         void (*event_write)(struct lib_ring_buffer_ctx *ctx, const void *src,
 184                             size_t len);
 185         /*
 186          * packet_avail_size returns the available size in the current
 187          * packet. Note that the size returned is only a hint, since it
 188          * may change due to concurrent writes.
 189          */
 190         size_t (*packet_avail_size)(struct channel *chan);
 191         //wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
 192         //wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 193         int (*is_finalized)(struct channel *chan);
 194         int (*is_disabled)(struct channel *chan);
 195 };
 196
 197 struct ltt_channel {
 198         unsigned int id;
 199         struct channel *chan;           /* Channel buffers */
 200         int enabled;
 201         struct lttng_ctx *ctx;
 202         /* Event ID management */
 203         struct ltt_session *session;
 204         struct file *file;              /* File associated to channel */
 205         unsigned int free_event_id;     /* Next event ID to allocate */
 206         struct cds_list_head list;      /* Channel list */
 207         struct ltt_channel_ops *ops;
 208         int header_type;                /* 0: unset, 1: compact, 2: large */
 209         int metadata_dumped:1;
 210 };
 211
 212 struct ltt_session {
 213         int active;                     /* Is trace session active ? */
 214         int been_active;                /* Has trace session been active ? */
 215         struct file *file;              /* File associated to session */
 216         struct ltt_channel *metadata;   /* Metadata channel */
 217         struct cds_list_head chan;      /* Channel list head */
 218         struct cds_list_head events;    /* Event list head */
 219         struct cds_list_head list;      /* Session list */
 220         unsigned int free_chan_id;      /* Next chan ID to allocate */
 221         uuid_t uuid;                    /* Trace session unique ID */
 222         int metadata_dumped:1;
 223 };
 224
 225 struct ltt_transport {
 226         char *name;
 227         struct cds_list_head node;
 228         struct ltt_channel_ops ops;
 229 };
 230
 231 struct ltt_session *ltt_session_create(void);
 232 int ltt_session_enable(struct ltt_session *session);
 233 int ltt_session_disable(struct ltt_session *session);
 234 void ltt_session_destroy(struct ltt_session *session);
 235
 236 struct ltt_channel *ltt_channel_create(struct ltt_session *session,
 237                                        const char *transport_name,
 238                                        void *buf_addr,
 239                                        size_t subbuf_size, size_t num_subbuf,
 240                                        unsigned int switch_timer_interval,
 241                                        unsigned int read_timer_interval);
 242 struct ltt_channel *ltt_global_channel_create(struct ltt_session *session,
 243                                        int overwrite, void *buf_addr,
 244                                        size_t subbuf_size, size_t num_subbuf,
 245                                        unsigned int switch_timer_interval,
 246                                        unsigned int read_timer_interval);
 247
 248 struct ltt_event *ltt_event_create(struct ltt_channel *chan,
 249                                    struct lttng_ust_event *event_param,
 250                                    void *filter);
 251
 252 int ltt_channel_enable(struct ltt_channel *channel);
 253 int ltt_channel_disable(struct ltt_channel *channel);
 254 int ltt_event_enable(struct ltt_event *event);
 255 int ltt_event_disable(struct ltt_event *event);
 256
 257 void ltt_transport_register(struct ltt_transport *transport);
 258 void ltt_transport_unregister(struct ltt_transport *transport);
 259
 260 void synchronize_trace(void);
 261 //int ltt_debugfs_abi_init(void);
 262 //void ltt_debugfs_abi_exit(void);
 263
 264 int ltt_probe_register(struct lttng_probe_desc *desc);
 265 void ltt_probe_unregister(struct lttng_probe_desc *desc);
 266 const struct lttng_event_desc *ltt_event_get(const char *name);
 267 void ltt_event_put(const struct lttng_event_desc *desc);
 268 int ltt_probes_init(void);
 269 void ltt_probes_exit(void);
 270 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx);
 271 void lttng_remove_context_field(struct lttng_ctx **ctx,
 272                                 struct lttng_ctx_field *field);
 273 void lttng_destroy_context(struct lttng_ctx *ctx);
 274 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 275
 276 //extern const struct file_operations lttng_tracepoint_list_fops;
 277
 278 #endif /* _LTT_EVENTS_H */