| 1 | /* |
| 2 | * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca> |
| 3 | * Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 4 | * 2012 - David Goulet <dgoulet@efficios.com> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License, version 2 only, |
| 8 | * as published by the Free Software Foundation. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 11 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 12 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 13 | * more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License along |
| 16 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 17 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 18 | */ |
| 19 | |
| 20 | #ifndef LIB_CONSUMER_H |
| 21 | #define LIB_CONSUMER_H |
| 22 | |
| 23 | #include <limits.h> |
| 24 | #include <poll.h> |
| 25 | #include <unistd.h> |
| 26 | |
| 27 | #include <lttng/lttng.h> |
| 28 | |
| 29 | #include <common/hashtable/hashtable.h> |
| 30 | #include <common/compat/fcntl.h> |
| 31 | #include <common/sessiond-comm/sessiond-comm.h> |
| 32 | |
| 33 | /* Commands for consumer */ |
| 34 | enum lttng_consumer_command { |
| 35 | LTTNG_CONSUMER_ADD_CHANNEL, |
| 36 | LTTNG_CONSUMER_ADD_STREAM, |
| 37 | /* pause, delete, active depending on fd state */ |
| 38 | LTTNG_CONSUMER_UPDATE_STREAM, |
| 39 | /* inform the consumer to quit when all fd has hang up */ |
| 40 | LTTNG_CONSUMER_STOP, |
| 41 | LTTNG_CONSUMER_ADD_RELAYD_SOCKET, |
| 42 | /* Inform the consumer to kill a specific relayd connection */ |
| 43 | LTTNG_CONSUMER_DESTROY_RELAYD, |
| 44 | /* Return to the sessiond if there is data pending for a session */ |
| 45 | LTTNG_CONSUMER_DATA_PENDING, |
| 46 | }; |
| 47 | |
| 48 | /* State of each fd in consumer */ |
| 49 | enum lttng_consumer_stream_state { |
| 50 | LTTNG_CONSUMER_ACTIVE_STREAM, |
| 51 | LTTNG_CONSUMER_PAUSE_STREAM, |
| 52 | LTTNG_CONSUMER_DELETE_STREAM, |
| 53 | }; |
| 54 | |
| 55 | enum lttng_consumer_type { |
| 56 | LTTNG_CONSUMER_UNKNOWN = 0, |
| 57 | LTTNG_CONSUMER_KERNEL, |
| 58 | LTTNG_CONSUMER64_UST, |
| 59 | LTTNG_CONSUMER32_UST, |
| 60 | }; |
| 61 | |
| 62 | enum consumer_endpoint_status { |
| 63 | CONSUMER_ENDPOINT_ACTIVE, |
| 64 | CONSUMER_ENDPOINT_INACTIVE, |
| 65 | }; |
| 66 | |
| 67 | struct lttng_consumer_channel { |
| 68 | struct lttng_ht_node_ulong node; |
| 69 | int key; |
| 70 | uint64_t max_sb_size; /* the subbuffer size for this channel */ |
| 71 | int refcount; /* Number of streams referencing this channel */ |
| 72 | /* |
| 73 | * The number of streams to receive initially. Used to guarantee that we do |
| 74 | * not destroy a channel before receiving all its associated streams. |
| 75 | */ |
| 76 | unsigned int nb_init_streams; |
| 77 | |
| 78 | /* For UST */ |
| 79 | int shm_fd; |
| 80 | int wait_fd; |
| 81 | void *mmap_base; |
| 82 | size_t mmap_len; |
| 83 | struct lttng_ust_shm_handle *handle; |
| 84 | int wait_fd_is_copy; |
| 85 | int cpucount; |
| 86 | }; |
| 87 | |
| 88 | /* Forward declaration for UST. */ |
| 89 | struct lttng_ust_lib_ring_buffer; |
| 90 | |
| 91 | /* |
| 92 | * Internal representation of the streams, sessiond_key is used to identify |
| 93 | * uniquely a stream. |
| 94 | */ |
| 95 | struct lttng_consumer_stream { |
| 96 | /* HT node used by the data_ht and metadata_ht */ |
| 97 | struct lttng_ht_node_ulong node; |
| 98 | /* HT node used in consumer_data.stream_list_ht */ |
| 99 | struct lttng_ht_node_ulong node_session_id; |
| 100 | struct lttng_consumer_channel *chan; /* associated channel */ |
| 101 | /* |
| 102 | * key is the key used by the session daemon to refer to the |
| 103 | * object in the consumer daemon. |
| 104 | */ |
| 105 | int key; |
| 106 | int shm_fd; |
| 107 | int wait_fd; |
| 108 | int out_fd; /* output file to write the data */ |
| 109 | off_t out_fd_offset; /* write position in the output file descriptor */ |
| 110 | char path_name[PATH_MAX]; /* tracefile name */ |
| 111 | enum lttng_consumer_stream_state state; |
| 112 | size_t shm_len; |
| 113 | void *mmap_base; |
| 114 | size_t mmap_len; |
| 115 | enum lttng_event_output output; /* splice or mmap */ |
| 116 | int shm_fd_is_copy; |
| 117 | int wait_fd_is_copy; |
| 118 | /* For UST */ |
| 119 | struct lttng_ust_lib_ring_buffer *buf; |
| 120 | int cpu; |
| 121 | int data_read; |
| 122 | int hangup_flush_done; |
| 123 | /* UID/GID of the user owning the session to which stream belongs */ |
| 124 | uid_t uid; |
| 125 | gid_t gid; |
| 126 | /* Network sequence number. Indicating on which relayd socket it goes. */ |
| 127 | int net_seq_idx; |
| 128 | /* Identify if the stream is the metadata */ |
| 129 | unsigned int metadata_flag; |
| 130 | /* Used when the stream is set for network streaming */ |
| 131 | uint64_t relayd_stream_id; |
| 132 | /* Next sequence number to use for trace packet */ |
| 133 | uint64_t next_net_seq_num; |
| 134 | /* |
| 135 | * Lock to use the stream FDs since they are used between threads. |
| 136 | * |
| 137 | * This is nested INSIDE the consumer_data lock. |
| 138 | * This is nested OUTSIDE consumer_relayd_sock_pair lock. |
| 139 | */ |
| 140 | pthread_mutex_t lock; |
| 141 | /* Tracing session id */ |
| 142 | uint64_t session_id; |
| 143 | /* |
| 144 | * Indicates if the stream end point is still active or not (network |
| 145 | * streaming or local file system). The thread "owning" the stream is |
| 146 | * handling this status and can be notified of a state change through the |
| 147 | * consumer data appropriate pipe. |
| 148 | */ |
| 149 | enum consumer_endpoint_status endpoint_status; |
| 150 | }; |
| 151 | |
| 152 | /* |
| 153 | * Internal representation of a relayd socket pair. |
| 154 | */ |
| 155 | struct consumer_relayd_sock_pair { |
| 156 | /* Network sequence number. */ |
| 157 | int net_seq_idx; |
| 158 | /* Number of stream associated with this relayd */ |
| 159 | unsigned int refcount; |
| 160 | |
| 161 | /* |
| 162 | * This flag indicates whether or not we should destroy this object. The |
| 163 | * destruction should ONLY occurs when this flag is set and the refcount is |
| 164 | * set to zero. |
| 165 | */ |
| 166 | unsigned int destroy_flag; |
| 167 | |
| 168 | /* |
| 169 | * Mutex protecting the control socket to avoid out of order packets |
| 170 | * between threads sending data to the relayd. Since metadata data is sent |
| 171 | * over that socket, at least two sendmsg() are needed (header + data) |
| 172 | * creating a race for packets to overlap between threads using it. |
| 173 | * |
| 174 | * This is nested INSIDE the consumer_data lock. |
| 175 | * This is nested INSIDE the stream lock. |
| 176 | */ |
| 177 | pthread_mutex_t ctrl_sock_mutex; |
| 178 | |
| 179 | /* Control socket. Command and metadata are passed over it */ |
| 180 | struct lttcomm_sock control_sock; |
| 181 | |
| 182 | /* |
| 183 | * We don't need a mutex at this point since we only splice or write single |
| 184 | * large chunk of data with a header appended at the begining. Moreover, |
| 185 | * this socket is for now only used in a single thread. |
| 186 | */ |
| 187 | struct lttcomm_sock data_sock; |
| 188 | struct lttng_ht_node_ulong node; |
| 189 | |
| 190 | /* Session id on both sides for the sockets. */ |
| 191 | uint64_t relayd_session_id; |
| 192 | uint64_t sessiond_session_id; |
| 193 | }; |
| 194 | |
| 195 | /* |
| 196 | * UST consumer local data to the program. One or more instance per |
| 197 | * process. |
| 198 | */ |
| 199 | struct lttng_consumer_local_data { |
| 200 | /* |
| 201 | * Function to call when data is available on a buffer. |
| 202 | * Returns the number of bytes read, or negative error value. |
| 203 | */ |
| 204 | ssize_t (*on_buffer_ready)(struct lttng_consumer_stream *stream, |
| 205 | struct lttng_consumer_local_data *ctx); |
| 206 | /* |
| 207 | * function to call when we receive a new channel, it receives a |
| 208 | * newly allocated channel, depending on the return code of this |
| 209 | * function, the new channel will be handled by the application |
| 210 | * or the library. |
| 211 | * |
| 212 | * Returns: |
| 213 | * > 0 (success, FD is kept by application) |
| 214 | * == 0 (success, FD is left to library) |
| 215 | * < 0 (error) |
| 216 | */ |
| 217 | int (*on_recv_channel)(struct lttng_consumer_channel *channel); |
| 218 | /* |
| 219 | * function to call when we receive a new stream, it receives a |
| 220 | * newly allocated stream, depending on the return code of this |
| 221 | * function, the new stream will be handled by the application |
| 222 | * or the library. |
| 223 | * |
| 224 | * Returns: |
| 225 | * > 0 (success, FD is kept by application) |
| 226 | * == 0 (success, FD is left to library) |
| 227 | * < 0 (error) |
| 228 | */ |
| 229 | int (*on_recv_stream)(struct lttng_consumer_stream *stream); |
| 230 | /* |
| 231 | * function to call when a stream is getting updated by the session |
| 232 | * daemon, this function receives the sessiond key and the new |
| 233 | * state, depending on the return code of this function the |
| 234 | * update of state for the stream is handled by the application |
| 235 | * or the library. |
| 236 | * |
| 237 | * Returns: |
| 238 | * > 0 (success, FD is kept by application) |
| 239 | * == 0 (success, FD is left to library) |
| 240 | * < 0 (error) |
| 241 | */ |
| 242 | int (*on_update_stream)(int sessiond_key, uint32_t state); |
| 243 | /* socket to communicate errors with sessiond */ |
| 244 | int consumer_error_socket; |
| 245 | /* socket to exchange commands with sessiond */ |
| 246 | char *consumer_command_sock_path; |
| 247 | /* communication with splice */ |
| 248 | int consumer_thread_pipe[2]; |
| 249 | int consumer_splice_metadata_pipe[2]; |
| 250 | /* Data stream poll thread pipe. To transfer data stream to the thread */ |
| 251 | int consumer_data_pipe[2]; |
| 252 | /* to let the signal handler wake up the fd receiver thread */ |
| 253 | int consumer_should_quit[2]; |
| 254 | /* Metadata poll thread pipe. Transfer metadata stream to it */ |
| 255 | int consumer_metadata_pipe[2]; |
| 256 | }; |
| 257 | |
| 258 | /* |
| 259 | * Library-level data. One instance per process. |
| 260 | */ |
| 261 | struct lttng_consumer_global_data { |
| 262 | /* |
| 263 | * At this time, this lock is used to ensure coherence between the count |
| 264 | * and number of element in the hash table. It's also a protection for |
| 265 | * concurrent read/write between threads. |
| 266 | * |
| 267 | * This is nested OUTSIDE the stream lock. |
| 268 | * This is nested OUTSIDE the consumer_relayd_sock_pair lock. |
| 269 | */ |
| 270 | pthread_mutex_t lock; |
| 271 | |
| 272 | /* |
| 273 | * Number of streams in the data stream hash table declared outside. |
| 274 | * Protected by consumer_data.lock. |
| 275 | */ |
| 276 | int stream_count; |
| 277 | |
| 278 | /* Channel hash table protected by consumer_data.lock. */ |
| 279 | struct lttng_ht *channel_ht; |
| 280 | /* |
| 281 | * Flag specifying if the local array of FDs needs update in the |
| 282 | * poll function. Protected by consumer_data.lock. |
| 283 | */ |
| 284 | unsigned int need_update; |
| 285 | enum lttng_consumer_type type; |
| 286 | |
| 287 | /* |
| 288 | * Relayd socket(s) hashtable indexed by network sequence number. Each |
| 289 | * stream has an index which associate the right relayd socket to use. |
| 290 | */ |
| 291 | struct lttng_ht *relayd_ht; |
| 292 | |
| 293 | /* |
| 294 | * This hash table contains all streams (metadata and data) indexed by |
| 295 | * session id. In other words, the ht is indexed by session id and each |
| 296 | * bucket contains the list of associated streams. |
| 297 | * |
| 298 | * This HT uses the "node_session_id" of the consumer stream. |
| 299 | */ |
| 300 | struct lttng_ht *stream_list_ht; |
| 301 | }; |
| 302 | |
| 303 | /* |
| 304 | * Session id mapping structure storred in relayd_session_id_ht. |
| 305 | */ |
| 306 | struct consumer_relayd_session_id { |
| 307 | uint64_t sessiond_id; |
| 308 | uint64_t relayd_id; |
| 309 | struct lttng_ht_node_ulong node; |
| 310 | }; |
| 311 | |
| 312 | /* |
| 313 | * Init consumer data structures. |
| 314 | */ |
| 315 | extern void lttng_consumer_init(void); |
| 316 | |
| 317 | /* |
| 318 | * Set the error socket for communication with a session daemon. |
| 319 | */ |
| 320 | extern void lttng_consumer_set_error_sock( |
| 321 | struct lttng_consumer_local_data *ctx, int sock); |
| 322 | |
| 323 | /* |
| 324 | * Set the command socket path for communication with a session daemon. |
| 325 | */ |
| 326 | extern void lttng_consumer_set_command_sock_path( |
| 327 | struct lttng_consumer_local_data *ctx, char *sock); |
| 328 | |
| 329 | /* |
| 330 | * Send return code to session daemon. |
| 331 | * |
| 332 | * Returns the return code of sendmsg : the number of bytes transmitted or -1 |
| 333 | * on error. |
| 334 | */ |
| 335 | extern int lttng_consumer_send_error( |
| 336 | struct lttng_consumer_local_data *ctx, int cmd); |
| 337 | |
| 338 | /* |
| 339 | * Called from signal handler to ensure a clean exit. |
| 340 | */ |
| 341 | extern void lttng_consumer_should_exit( |
| 342 | struct lttng_consumer_local_data *ctx); |
| 343 | |
| 344 | /* |
| 345 | * Cleanup the daemon's socket on exit. |
| 346 | */ |
| 347 | extern void lttng_consumer_cleanup(void); |
| 348 | |
| 349 | /* |
| 350 | * Flush pending writes to trace output disk file. |
| 351 | */ |
| 352 | extern void lttng_consumer_sync_trace_file( |
| 353 | struct lttng_consumer_stream *stream, off_t orig_offset); |
| 354 | |
| 355 | /* |
| 356 | * Poll on the should_quit pipe and the command socket return -1 on error and |
| 357 | * should exit, 0 if data is available on the command socket |
| 358 | */ |
| 359 | extern int lttng_consumer_poll_socket(struct pollfd *kconsumer_sockpoll); |
| 360 | |
| 361 | extern struct lttng_consumer_stream *consumer_allocate_stream( |
| 362 | int channel_key, int stream_key, |
| 363 | int shm_fd, int wait_fd, |
| 364 | enum lttng_consumer_stream_state state, |
| 365 | uint64_t mmap_len, |
| 366 | enum lttng_event_output output, |
| 367 | const char *path_name, |
| 368 | uid_t uid, |
| 369 | gid_t gid, |
| 370 | int net_index, |
| 371 | int metadata_flag, |
| 372 | uint64_t session_id, |
| 373 | int *alloc_ret); |
| 374 | extern void consumer_del_stream(struct lttng_consumer_stream *stream, |
| 375 | struct lttng_ht *ht); |
| 376 | extern void consumer_del_metadata_stream(struct lttng_consumer_stream *stream, |
| 377 | struct lttng_ht *ht); |
| 378 | extern void consumer_del_channel(struct lttng_consumer_channel *channel); |
| 379 | extern struct lttng_consumer_channel *consumer_allocate_channel( |
| 380 | int channel_key, |
| 381 | int shm_fd, int wait_fd, |
| 382 | uint64_t mmap_len, |
| 383 | uint64_t max_sb_size, |
| 384 | unsigned int nb_init_streams); |
| 385 | int consumer_add_channel(struct lttng_consumer_channel *channel); |
| 386 | |
| 387 | /* lttng-relayd consumer command */ |
| 388 | struct consumer_relayd_sock_pair *consumer_allocate_relayd_sock_pair( |
| 389 | int net_seq_idx); |
| 390 | struct consumer_relayd_sock_pair *consumer_find_relayd(int key); |
| 391 | int consumer_handle_stream_before_relayd(struct lttng_consumer_stream *stream, |
| 392 | size_t data_size); |
| 393 | void consumer_steal_stream_key(int key, struct lttng_ht *ht); |
| 394 | |
| 395 | extern struct lttng_consumer_local_data *lttng_consumer_create( |
| 396 | enum lttng_consumer_type type, |
| 397 | ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream, |
| 398 | struct lttng_consumer_local_data *ctx), |
| 399 | int (*recv_channel)(struct lttng_consumer_channel *channel), |
| 400 | int (*recv_stream)(struct lttng_consumer_stream *stream), |
| 401 | int (*update_stream)(int sessiond_key, uint32_t state)); |
| 402 | extern void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx); |
| 403 | extern ssize_t lttng_consumer_on_read_subbuffer_mmap( |
| 404 | struct lttng_consumer_local_data *ctx, |
| 405 | struct lttng_consumer_stream *stream, unsigned long len, |
| 406 | unsigned long padding); |
| 407 | extern ssize_t lttng_consumer_on_read_subbuffer_splice( |
| 408 | struct lttng_consumer_local_data *ctx, |
| 409 | struct lttng_consumer_stream *stream, unsigned long len, |
| 410 | unsigned long padding); |
| 411 | extern int lttng_consumer_take_snapshot(struct lttng_consumer_local_data *ctx, |
| 412 | struct lttng_consumer_stream *stream); |
| 413 | extern int lttng_consumer_get_produced_snapshot( |
| 414 | struct lttng_consumer_local_data *ctx, |
| 415 | struct lttng_consumer_stream *stream, |
| 416 | unsigned long *pos); |
| 417 | extern void *consumer_thread_metadata_poll(void *data); |
| 418 | extern void *consumer_thread_data_poll(void *data); |
| 419 | extern void *consumer_thread_sessiond_poll(void *data); |
| 420 | extern int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx, |
| 421 | int sock, struct pollfd *consumer_sockpoll); |
| 422 | |
| 423 | ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream, |
| 424 | struct lttng_consumer_local_data *ctx); |
| 425 | int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream); |
| 426 | int consumer_add_relayd_socket(int net_seq_idx, int sock_type, |
| 427 | struct lttng_consumer_local_data *ctx, int sock, |
| 428 | struct pollfd *consumer_sockpoll, struct lttcomm_sock *relayd_sock, |
| 429 | unsigned int sessiond_id); |
| 430 | void consumer_flag_relayd_for_destroy( |
| 431 | struct consumer_relayd_sock_pair *relayd); |
| 432 | int consumer_data_pending(uint64_t id); |
| 433 | int consumer_send_status_msg(int sock, int ret_code); |
| 434 | |
| 435 | #endif /* LIB_CONSUMER_H */ |