src/common/consumer/consumer.h

   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  *               2018 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License, version 2 only,
   9  * as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  14  * more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #ifndef LIB_CONSUMER_H
  22 #define LIB_CONSUMER_H
  23
  24 #include <limits.h>
  25 #include <poll.h>
  26 #include <unistd.h>
  27 #include <urcu/list.h>
  28
  29 #include <lttng/lttng.h>
  30
  31 #include <common/hashtable/hashtable.h>
  32 #include <common/compat/fcntl.h>
  33 #include <common/compat/uuid.h>
  34 #include <common/sessiond-comm/sessiond-comm.h>
  35 #include <common/pipe.h>
  36 #include <common/index/ctf-index.h>
  37
  38 /* Commands for consumer */
  39 enum lttng_consumer_command {
  40         LTTNG_CONSUMER_ADD_CHANNEL,
  41         LTTNG_CONSUMER_ADD_STREAM,
  42         /* pause, delete, active depending on fd state */
  43         LTTNG_CONSUMER_UPDATE_STREAM,
  44         /* inform the consumer to quit when all fd has hang up */
  45         LTTNG_CONSUMER_STOP,    /* deprecated */
  46         LTTNG_CONSUMER_ADD_RELAYD_SOCKET,
  47         /* Inform the consumer to kill a specific relayd connection */
  48         LTTNG_CONSUMER_DESTROY_RELAYD,
  49         /* Return to the sessiond if there is data pending for a session */
  50         LTTNG_CONSUMER_DATA_PENDING,
  51         /* Consumer creates a channel and returns it to sessiond. */
  52         LTTNG_CONSUMER_ASK_CHANNEL_CREATION,
  53         LTTNG_CONSUMER_GET_CHANNEL,
  54         LTTNG_CONSUMER_DESTROY_CHANNEL,
  55         LTTNG_CONSUMER_PUSH_METADATA,
  56         LTTNG_CONSUMER_CLOSE_METADATA,
  57         LTTNG_CONSUMER_SETUP_METADATA,
  58         LTTNG_CONSUMER_FLUSH_CHANNEL,
  59         LTTNG_CONSUMER_SNAPSHOT_CHANNEL,
  60         LTTNG_CONSUMER_SNAPSHOT_METADATA,
  61         LTTNG_CONSUMER_STREAMS_SENT,
  62         LTTNG_CONSUMER_DISCARDED_EVENTS,
  63         LTTNG_CONSUMER_LOST_PACKETS,
  64         LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL,
  65         LTTNG_CONSUMER_SET_CHANNEL_MONITOR_PIPE,
  66         LTTNG_CONSUMER_ROTATE_CHANNEL,
  67         LTTNG_CONSUMER_ROTATE_RENAME,
  68         LTTNG_CONSUMER_CHECK_ROTATION_PENDING_LOCAL,
  69         LTTNG_CONSUMER_CHECK_ROTATION_PENDING_RELAY,
  70         LTTNG_CONSUMER_MKDIR,
  71 };
  72
  73 /* State of each fd in consumer */
  74 enum lttng_consumer_stream_state {
  75         LTTNG_CONSUMER_ACTIVE_STREAM,
  76         LTTNG_CONSUMER_PAUSE_STREAM,
  77         LTTNG_CONSUMER_DELETE_STREAM,
  78 };
  79
  80 enum lttng_consumer_type {
  81         LTTNG_CONSUMER_UNKNOWN = 0,
  82         LTTNG_CONSUMER_KERNEL,
  83         LTTNG_CONSUMER64_UST,
  84         LTTNG_CONSUMER32_UST,
  85 };
  86
  87 enum consumer_endpoint_status {
  88         CONSUMER_ENDPOINT_ACTIVE,
  89         CONSUMER_ENDPOINT_INACTIVE,
  90 };
  91
  92 enum consumer_channel_output {
  93         CONSUMER_CHANNEL_MMAP   = 0,
  94         CONSUMER_CHANNEL_SPLICE = 1,
  95 };
  96
  97 enum consumer_channel_type {
  98         CONSUMER_CHANNEL_TYPE_METADATA  = 0,
  99         CONSUMER_CHANNEL_TYPE_DATA      = 1,
 100 };
 101
 102 extern struct lttng_consumer_global_data consumer_data;
 103
 104 struct stream_list {
 105         struct cds_list_head head;
 106         unsigned int count;
 107 };
 108
 109 /* Stub. */
 110 struct consumer_metadata_cache;
 111
 112 struct lttng_consumer_channel {
 113         /* HT node used for consumer_data.channel_ht */
 114         struct lttng_ht_node_u64 node;
 115         /* HT node used for consumer_data.channels_by_session_id_ht */
 116         struct lttng_ht_node_u64 channels_by_session_id_ht_node;
 117         /* Indexed key. Incremented value in the consumer. */
 118         uint64_t key;
 119         /* Number of streams referencing this channel */
 120         int refcount;
 121         /* Tracing session id on the session daemon side. */
 122         uint64_t session_id;
 123         /*
 124          * Session id when requesting metadata to the session daemon for
 125          * a session with per-PID buffers.
 126          */
 127         uint64_t session_id_per_pid;
 128         /* Channel trace file path name. */
 129         char pathname[PATH_MAX];
 130         /* Channel name. */
 131         char name[LTTNG_SYMBOL_NAME_LEN];
 132         /* UID and GID of the session owning this channel. */
 133         uid_t uid;
 134         gid_t gid;
 135         /* Relayd id of the channel. -1ULL if it does not apply. */
 136         uint64_t relayd_id;
 137         /*
 138          * Number of streams NOT initialized yet. This is used in order to not
 139          * delete this channel if streams are getting initialized.
 140          */
 141         unsigned int nb_init_stream_left;
 142         /* Output type (mmap or splice). */
 143         enum consumer_channel_output output;
 144         /* Channel type for stream */
 145         enum consumer_channel_type type;
 146
 147         /* For UST */
 148         uid_t ust_app_uid;      /* Application UID. */
 149         struct ustctl_consumer_channel *uchan;
 150         unsigned char uuid[UUID_STR_LEN];
 151         /*
 152          * Temporary stream list used to store the streams once created and waiting
 153          * to be sent to the session daemon by receiving the
 154          * LTTNG_CONSUMER_GET_CHANNEL.
 155          */
 156         struct stream_list streams;
 157
 158         /*
 159          * Set if the channel is metadata. We keep a reference to the stream
 160          * because we have to flush data once pushed by the session daemon. For a
 161          * regular channel, this is always set to NULL.
 162          */
 163         struct lttng_consumer_stream *metadata_stream;
 164
 165         /* for UST */
 166         int wait_fd;
 167         /* Node within channel thread ht */
 168         struct lttng_ht_node_u64 wait_fd_node;
 169
 170         /* Metadata cache is metadata channel */
 171         struct consumer_metadata_cache *metadata_cache;
 172
 173         /* For UST metadata periodical flush */
 174         int switch_timer_enabled;
 175         timer_t switch_timer;
 176         int switch_timer_error;
 177
 178         /* For the live mode */
 179         int live_timer_enabled;
 180         timer_t live_timer;
 181         int live_timer_error;
 182
 183         /* For channel monitoring timer. */
 184         int monitor_timer_enabled;
 185         timer_t monitor_timer;
 186
 187         /* On-disk circular buffer */
 188         uint64_t tracefile_size;
 189         uint64_t tracefile_count;
 190         /*
 191          * Monitor or not the streams of this channel meaning this indicates if the
 192          * streams should be sent to the data/metadata thread or added to the no
 193          * monitor list of the channel.
 194          */
 195         unsigned int monitor;
 196
 197         /*
 198          * Channel lock.
 199          *
 200          * This lock protects against concurrent update of channel.
 201          *
 202          * This is nested INSIDE the consumer data lock.
 203          * This is nested OUTSIDE the channel timer lock.
 204          * This is nested OUTSIDE the metadata cache lock.
 205          * This is nested OUTSIDE stream lock.
 206          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 207          */
 208         pthread_mutex_t lock;
 209
 210         /*
 211          * Channel teardown lock.
 212          *
 213          * This lock protect against teardown of channel. It is _never_
 214          * taken by the timer handler.
 215          *
 216          * This is nested INSIDE the consumer data lock.
 217          * This is nested INSIDE the channel lock.
 218          * This is nested OUTSIDE the metadata cache lock.
 219          * This is nested OUTSIDE stream lock.
 220          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 221          */
 222         pthread_mutex_t timer_lock;
 223
 224         /* Timer value in usec for live streaming. */
 225         unsigned int live_timer_interval;
 226
 227         int *stream_fds;
 228         int nr_stream_fds;
 229         char root_shm_path[PATH_MAX];
 230         char shm_path[PATH_MAX];
 231         /* Total number of discarded events for that channel. */
 232         uint64_t discarded_events;
 233         /* Total number of missed packets due to overwriting (overwrite). */
 234         uint64_t lost_packets;
 235
 236         bool streams_sent_to_relayd;
 237
 238         /*
 239          * The chunk id where we currently write the data. This value is sent
 240          * to the relay when we add a stream and when a stream rotates. This
 241          * allows to keep track of where each stream on the relay is writing.
 242          */
 243         uint64_t current_chunk_id;
 244 };
 245
 246 /*
 247  * Internal representation of the streams, sessiond_key is used to identify
 248  * uniquely a stream.
 249  */
 250 struct lttng_consumer_stream {
 251         /* HT node used by the data_ht and metadata_ht */
 252         struct lttng_ht_node_u64 node;
 253         /* stream indexed per channel key node */
 254         struct lttng_ht_node_u64 node_channel_id;
 255         /* HT node used in consumer_data.stream_list_ht */
 256         struct lttng_ht_node_u64 node_session_id;
 257         /* Pointer to associated channel. */
 258         struct lttng_consumer_channel *chan;
 259
 260         /* Key by which the stream is indexed for 'node'. */
 261         uint64_t key;
 262         /*
 263          * File descriptor of the data output file. This can be either a file or a
 264          * socket fd for relayd streaming.
 265          */
 266         int out_fd; /* output file to write the data */
 267         /* Write position in the output file descriptor */
 268         off_t out_fd_offset;
 269         /* Amount of bytes written to the output */
 270         uint64_t output_written;
 271         enum lttng_consumer_stream_state state;
 272         int shm_fd_is_copy;
 273         int data_read;
 274         int hangup_flush_done;
 275
 276         /*
 277          * Whether the stream is in a "complete" state (e.g. it does not have a
 278          * partially written sub-buffer.
 279          *
 280          * Initialized to "false" on stream creation (first packet is empty).
 281          *
 282          * The various transitions of the quiescent state are:
 283          *     - On "start" tracing: set to false, since the stream is not
 284          *       "complete".
 285          *     - On "stop" tracing: if !quiescent -> flush FINAL (update
 286          *       timestamp_end), and set to true; the stream has entered a
 287          *       complete/quiescent state.
 288          *     - On "destroy" or stream/application hang-up: if !quiescent ->
 289          *       flush FINAL, and set to true.
 290          *
 291          * NOTE: Update and read are protected by the stream lock.
 292          */
 293         bool quiescent;
 294
 295         /*
 296          * metadata_timer_lock protects flags waiting_on_metadata and
 297          * missed_metadata_flush.
 298          */
 299         pthread_mutex_t metadata_timer_lock;
 300         /*
 301          * Flag set when awaiting metadata to be pushed. Used in the
 302          * timer thread to skip waiting on the stream (and stream lock) to
 303          * ensure we can proceed to flushing metadata in live mode.
 304          */
 305         bool waiting_on_metadata;
 306         /* Raised when a timer misses a metadata flush. */
 307         bool missed_metadata_flush;
 308
 309         enum lttng_event_output output;
 310         /* Maximum subbuffer size. */
 311         unsigned long max_sb_size;
 312
 313         /*
 314          * Still used by the kernel for MMAP output. For UST, the ustctl getter is
 315          * used for the mmap base and offset.
 316          */
 317         void *mmap_base;
 318         unsigned long mmap_len;
 319
 320         /* For UST */
 321
 322         int wait_fd;
 323         /* UID/GID of the user owning the session to which stream belongs */
 324         uid_t uid;
 325         gid_t gid;
 326         /* Network sequence number. Indicating on which relayd socket it goes. */
 327         uint64_t net_seq_idx;
 328         /*
 329          * Indicate if this stream was successfully sent to a relayd. This is set
 330          * after the refcount of the relayd is incremented and is checked when the
 331          * stream is closed before decrementing the refcount in order to avoid an
 332          * unbalanced state.
 333          */
 334         unsigned int sent_to_relayd;
 335
 336         /* Identify if the stream is the metadata */
 337         unsigned int metadata_flag;
 338         /*
 339          * Last known metadata version, reset the metadata file in case
 340          * of change.
 341          */
 342         uint64_t metadata_version;
 343         /* Used when the stream is set for network streaming */
 344         uint64_t relayd_stream_id;
 345         /*
 346          * When sending a stream packet to a relayd, this number is used to track
 347          * the packet sent by the consumer and seen by the relayd. When sending the
 348          * data header to the relayd, this number is sent and if the transmission
 349          * was successful, it is incremented.
 350          *
 351          * Even if the full data is not fully transmitted it won't matter since
 352          * only two possible error can happen after that where either the relayd
 353          * died or a read error is detected on the stream making this value useless
 354          * after that.
 355          *
 356          * This value SHOULD be read/updated atomically or with the lock acquired.
 357          */
 358         uint64_t next_net_seq_num;
 359         /*
 360          * Lock to use the stream FDs since they are used between threads.
 361          *
 362          * This is nested INSIDE the consumer_data lock.
 363          * This is nested INSIDE the channel lock.
 364          * This is nested INSIDE the channel timer lock.
 365          * This is nested OUTSIDE the metadata cache lock.
 366          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 367          */
 368         pthread_mutex_t lock;
 369         /* Tracing session id */
 370         uint64_t session_id;
 371         /*
 372          * Indicates if the stream end point is still active or not (network
 373          * streaming or local file system). The thread "owning" the stream is
 374          * handling this status and can be notified of a state change through the
 375          * consumer data appropriate pipe.
 376          */
 377         enum consumer_endpoint_status endpoint_status;
 378         /* Stream name. Format is: <channel_name>_<cpu_number> */
 379         char name[LTTNG_SYMBOL_NAME_LEN];
 380         /* Internal state of libustctl. */
 381         struct ustctl_consumer_stream *ustream;
 382         struct cds_list_head send_node;
 383         /* On-disk circular buffer */
 384         uint64_t tracefile_size_current;
 385         uint64_t tracefile_count_current;
 386         /*
 387          * Monitor or not the streams of this channel meaning this indicates if the
 388          * streams should be sent to the data/metadata thread or added to the no
 389          * monitor list of the channel.
 390          */
 391         unsigned int monitor;
 392         /*
 393          * Indicate if the stream is globally visible meaning that it has been
 394          * added to the multiple hash tables. If *not* set, NO lock should be
 395          * acquired in the destroy path.
 396          */
 397         unsigned int globally_visible;
 398         /*
 399          * Pipe to wake up the metadata poll thread when the UST metadata
 400          * cache is updated.
 401          */
 402         int ust_metadata_poll_pipe[2];
 403         /*
 404          * How much metadata was read from the metadata cache and sent
 405          * to the channel.
 406          */
 407         uint64_t ust_metadata_pushed;
 408         /*
 409          * Copy of the last discarded event value to detect the overflow of
 410          * the counter.
 411          */
 412         uint64_t last_discarded_events;
 413         /* Copy of the sequence number of the last packet extracted. */
 414         uint64_t last_sequence_number;
 415         /*
 416          * A stream is created with a trace_archive_id matching the session's
 417          * current trace archive id at the time of the creation of the stream.
 418          * It is incremented when the rotate_position is reached.
 419          */
 420         uint64_t trace_archive_id;
 421         /*
 422          * Index file object of the index file for this stream.
 423          */
 424         struct lttng_index_file *index_file;
 425
 426         /*
 427          * Local pipe to extract data when using splice.
 428          */
 429         int splice_pipe[2];
 430
 431         /*
 432          * Rendez-vous point between data and metadata stream in live mode.
 433          */
 434         pthread_cond_t metadata_rdv;
 435         pthread_mutex_t metadata_rdv_lock;
 436
 437         /*
 438          * rotate_position represents the position in the ring-buffer that has to
 439          * be flushed to disk to complete the ongoing rotation. When that position
 440          * is reached, this tracefile can be closed and a new one is created in
 441          * channel_read_only_attributes.path.
 442          */
 443         unsigned long rotate_position;
 444
 445         /*
 446          * Read-only copies of channel values. We cannot safely access the
 447          * channel from a stream, so we need to have a local copy of these
 448          * fields in the stream object. These fields should be removed from
 449          * the stream objects when we introduce refcounting.
 450          */
 451         struct {
 452                 char path[LTTNG_PATH_MAX];
 453                 uint64_t tracefile_size;
 454         } channel_read_only_attributes;
 455
 456         /*
 457          * Flag to inform the data or metadata thread that a stream is
 458          * ready to be rotated.
 459          */
 460         bool rotate_ready;
 461
 462         /* Indicate if the stream still has some data to be read. */
 463         unsigned int has_data:1;
 464         /*
 465          * Inform the consumer or relay to reset the metadata
 466          * file before writing in it (regeneration).
 467          */
 468         unsigned int reset_metadata_flag:1;
 469 };
 470
 471 /*
 472  * Internal representation of a relayd socket pair.
 473  */
 474 struct consumer_relayd_sock_pair {
 475         /* Network sequence number. */
 476         uint64_t net_seq_idx;
 477         /* Number of stream associated with this relayd */
 478         int refcount;
 479
 480         /*
 481          * This flag indicates whether or not we should destroy this object. The
 482          * destruction should ONLY occurs when this flag is set and the refcount is
 483          * set to zero.
 484          */
 485         unsigned int destroy_flag;
 486
 487         /*
 488          * Mutex protecting the control socket to avoid out of order packets
 489          * between threads sending data to the relayd. Since metadata data is sent
 490          * over that socket, at least two sendmsg() are needed (header + data)
 491          * creating a race for packets to overlap between threads using it.
 492          *
 493          * This is nested INSIDE the consumer_data lock.
 494          * This is nested INSIDE the stream lock.
 495          */
 496         pthread_mutex_t ctrl_sock_mutex;
 497
 498         /* Control socket. Command and metadata are passed over it */
 499         struct lttcomm_relayd_sock control_sock;
 500
 501         /*
 502          * We don't need a mutex at this point since we only splice or write single
 503          * large chunk of data with a header appended at the begining. Moreover,
 504          * this socket is for now only used in a single thread.
 505          */
 506         struct lttcomm_relayd_sock data_sock;
 507         struct lttng_ht_node_u64 node;
 508
 509         /* Session id on both sides for the sockets. */
 510         uint64_t relayd_session_id;
 511         uint64_t sessiond_session_id;
 512         struct lttng_consumer_local_data *ctx;
 513 };
 514
 515 /*
 516  * UST consumer local data to the program. One or more instance per
 517  * process.
 518  */
 519 struct lttng_consumer_local_data {
 520         /*
 521          * Function to call when data is available on a buffer.
 522          * Returns the number of bytes read, or negative error value.
 523          */
 524         ssize_t (*on_buffer_ready)(struct lttng_consumer_stream *stream,
 525                         struct lttng_consumer_local_data *ctx);
 526         /*
 527          * function to call when we receive a new channel, it receives a
 528          * newly allocated channel, depending on the return code of this
 529          * function, the new channel will be handled by the application
 530          * or the library.
 531          *
 532          * Returns:
 533          *    > 0 (success, FD is kept by application)
 534          *   == 0 (success, FD is left to library)
 535          *    < 0 (error)
 536          */
 537         int (*on_recv_channel)(struct lttng_consumer_channel *channel);
 538         /*
 539          * function to call when we receive a new stream, it receives a
 540          * newly allocated stream, depending on the return code of this
 541          * function, the new stream will be handled by the application
 542          * or the library.
 543          *
 544          * Returns:
 545          *    > 0 (success, FD is kept by application)
 546          *   == 0 (success, FD is left to library)
 547          *    < 0 (error)
 548          */
 549         int (*on_recv_stream)(struct lttng_consumer_stream *stream);
 550         /*
 551          * function to call when a stream is getting updated by the session
 552          * daemon, this function receives the sessiond key and the new
 553          * state, depending on the return code of this function the
 554          * update of state for the stream is handled by the application
 555          * or the library.
 556          *
 557          * Returns:
 558          *    > 0 (success, FD is kept by application)
 559          *   == 0 (success, FD is left to library)
 560          *    < 0 (error)
 561          */
 562         int (*on_update_stream)(uint64_t sessiond_key, uint32_t state);
 563         enum lttng_consumer_type type;
 564         /* socket to communicate errors with sessiond */
 565         int consumer_error_socket;
 566         /* socket to ask metadata to sessiond. */
 567         int consumer_metadata_socket;
 568         /*
 569          * Protect consumer_metadata_socket.
 570          *
 571          * This is nested OUTSIDE the metadata cache lock.
 572          */
 573         pthread_mutex_t metadata_socket_lock;
 574         /* socket to exchange commands with sessiond */
 575         char *consumer_command_sock_path;
 576         /* communication with splice */
 577         int consumer_channel_pipe[2];
 578         /* Data stream poll thread pipe. To transfer data stream to the thread */
 579         struct lttng_pipe *consumer_data_pipe;
 580
 581         /*
 582          * Data thread use that pipe to catch wakeup from read subbuffer that
 583          * detects that there is still data to be read for the stream encountered.
 584          * Before doing so, the stream is flagged to indicate that there is still
 585          * data to be read.
 586          *
 587          * Both pipes (read/write) are owned and used inside the data thread.
 588          */
 589         struct lttng_pipe *consumer_wakeup_pipe;
 590         /* Indicate if the wakeup thread has been notified. */
 591         unsigned int has_wakeup:1;
 592
 593         /* to let the signal handler wake up the fd receiver thread */
 594         int consumer_should_quit[2];
 595         /* Metadata poll thread pipe. Transfer metadata stream to it */
 596         struct lttng_pipe *consumer_metadata_pipe;
 597         /*
 598          * Pipe used by the channel monitoring timers to provide state samples
 599          * to the session daemon (write-only).
 600          */
 601         int channel_monitor_pipe;
 602 };
 603
 604 /*
 605  * Library-level data. One instance per process.
 606  */
 607 struct lttng_consumer_global_data {
 608         /*
 609          * At this time, this lock is used to ensure coherence between the count
 610          * and number of element in the hash table. It's also a protection for
 611          * concurrent read/write between threads.
 612          *
 613          * This is nested OUTSIDE the stream lock.
 614          * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
 615          */
 616         pthread_mutex_t lock;
 617
 618         /*
 619          * Number of streams in the data stream hash table declared outside.
 620          * Protected by consumer_data.lock.
 621          */
 622         int stream_count;
 623
 624         /* Channel hash table protected by consumer_data.lock. */
 625         struct lttng_ht *channel_ht;
 626         /* Channel hash table indexed by session id. */
 627         struct lttng_ht *channels_by_session_id_ht;
 628         /*
 629          * Flag specifying if the local array of FDs needs update in the
 630          * poll function. Protected by consumer_data.lock.
 631          */
 632         unsigned int need_update;
 633         enum lttng_consumer_type type;
 634
 635         /*
 636          * Relayd socket(s) hashtable indexed by network sequence number. Each
 637          * stream has an index which associate the right relayd socket to use.
 638          */
 639         struct lttng_ht *relayd_ht;
 640
 641         /*
 642          * This hash table contains all streams (metadata and data) indexed by
 643          * session id. In other words, the ht is indexed by session id and each
 644          * bucket contains the list of associated streams.
 645          *
 646          * This HT uses the "node_session_id" of the consumer stream.
 647          */
 648         struct lttng_ht *stream_list_ht;
 649
 650         /*
 651          * This HT uses the "node_channel_id" of the consumer stream.
 652          */
 653         struct lttng_ht *stream_per_chan_id_ht;
 654 };
 655
 656 /*
 657  * Set to nonzero when the consumer is exiting. Updated by signal
 658  * handler and thread exit, read by threads.
 659  */
 660 extern int consumer_quit;
 661
 662 /*
 663  * Set to nonzero when the consumer is exiting. Updated by signal
 664  * handler and thread exit, read by threads.
 665  */
 666 extern int consumer_quit;
 667
 668 /* Flag used to temporarily pause data consumption from testpoints. */
 669 extern int data_consumption_paused;
 670
 671 /* Return a human-readable consumer type string that is suitable for logging. */
 672 static inline
 673 const char *lttng_consumer_type_str(enum lttng_consumer_type type)
 674 {
 675         switch (type) {
 676         case LTTNG_CONSUMER_UNKNOWN:
 677                 return "unknown";
 678         case LTTNG_CONSUMER_KERNEL:
 679                 return "kernel";
 680         case LTTNG_CONSUMER32_UST:
 681                 return "32-bit user space";
 682         case LTTNG_CONSUMER64_UST:
 683                 return "64-bit user space";
 684         default:
 685                 abort();
 686         }
 687 }
 688
 689 /*
 690  * Init consumer data structures.
 691  */
 692 int lttng_consumer_init(void);
 693
 694 /*
 695  * Set the error socket for communication with a session daemon.
 696  */
 697 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data *ctx,
 698                 int sock);
 699
 700 /*
 701  * Set the command socket path for communication with a session daemon.
 702  */
 703 void lttng_consumer_set_command_sock_path(
 704                 struct lttng_consumer_local_data *ctx, char *sock);
 705
 706 /*
 707  * Send return code to session daemon.
 708  *
 709  * Returns the return code of sendmsg : the number of bytes transmitted or -1
 710  * on error.
 711  */
 712 int lttng_consumer_send_error(struct lttng_consumer_local_data *ctx, int cmd);
 713
 714 /*
 715  * Called from signal handler to ensure a clean exit.
 716  */
 717 void lttng_consumer_should_exit(struct lttng_consumer_local_data *ctx);
 718
 719 /*
 720  * Cleanup the daemon's socket on exit.
 721  */
 722 void lttng_consumer_cleanup(void);
 723
 724 /*
 725  * Poll on the should_quit pipe and the command socket return -1 on error and
 726  * should exit, 0 if data is available on the command socket
 727  */
 728 int lttng_consumer_poll_socket(struct pollfd *kconsumer_sockpoll);
 729
 730 /*
 731  * Copy the fields from the channel that need to be accessed (read-only)
 732  * directly from the stream.
 733  */
 734 void consumer_stream_update_channel_attributes(
 735                 struct lttng_consumer_stream *stream,
 736                 struct lttng_consumer_channel *channel);
 737
 738 struct lttng_consumer_stream *consumer_allocate_stream(uint64_t channel_key,
 739                 uint64_t stream_key,
 740                 enum lttng_consumer_stream_state state,
 741                 const char *channel_name,
 742                 uid_t uid,
 743                 gid_t gid,
 744                 uint64_t relayd_id,
 745                 uint64_t session_id,
 746                 int cpu,
 747                 int *alloc_ret,
 748                 enum consumer_channel_type type,
 749                 unsigned int monitor,
 750                 uint64_t trace_archive_id);
 751 struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
 752                 uint64_t session_id,
 753                 const char *pathname,
 754                 const char *name,
 755                 uid_t uid,
 756                 gid_t gid,
 757                 uint64_t relayd_id,
 758                 enum lttng_event_output output,
 759                 uint64_t tracefile_size,
 760                 uint64_t tracefile_count,
 761                 uint64_t session_id_per_pid,
 762                 unsigned int monitor,
 763                 unsigned int live_timer_interval,
 764                 const char *root_shm_path,
 765                 const char *shm_path);
 766 void consumer_del_stream(struct lttng_consumer_stream *stream,
 767                 struct lttng_ht *ht);
 768 void consumer_del_metadata_stream(struct lttng_consumer_stream *stream,
 769                 struct lttng_ht *ht);
 770 int consumer_add_channel(struct lttng_consumer_channel *channel,
 771                 struct lttng_consumer_local_data *ctx);
 772 void consumer_del_channel(struct lttng_consumer_channel *channel);
 773
 774 /* lttng-relayd consumer command */
 775 struct consumer_relayd_sock_pair *consumer_find_relayd(uint64_t key);
 776 int consumer_send_relayd_stream(struct lttng_consumer_stream *stream, char *path);
 777 int consumer_send_relayd_streams_sent(uint64_t net_seq_idx);
 778 void close_relayd_stream(struct lttng_consumer_stream *stream);
 779 struct lttng_consumer_channel *consumer_find_channel(uint64_t key);
 780 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream *stream,
 781                 size_t data_size);
 782 void consumer_steal_stream_key(int key, struct lttng_ht *ht);
 783
 784 struct lttng_consumer_local_data *lttng_consumer_create(
 785                 enum lttng_consumer_type type,
 786                 ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream,
 787                         struct lttng_consumer_local_data *ctx),
 788                 int (*recv_channel)(struct lttng_consumer_channel *channel),
 789                 int (*recv_stream)(struct lttng_consumer_stream *stream),
 790                 int (*update_stream)(uint64_t sessiond_key, uint32_t state));
 791 void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx);
 792 ssize_t lttng_consumer_on_read_subbuffer_mmap(
 793                 struct lttng_consumer_local_data *ctx,
 794                 struct lttng_consumer_stream *stream, unsigned long len,
 795                 unsigned long padding,
 796                 struct ctf_packet_index *index);
 797 ssize_t lttng_consumer_on_read_subbuffer_splice(
 798                 struct lttng_consumer_local_data *ctx,
 799                 struct lttng_consumer_stream *stream, unsigned long len,
 800                 unsigned long padding,
 801                 struct ctf_packet_index *index);
 802 int lttng_consumer_sample_snapshot_positions(struct lttng_consumer_stream *stream);
 803 int lttng_consumer_take_snapshot(struct lttng_consumer_stream *stream);
 804 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
 805                 unsigned long *pos);
 806 int lttng_consumer_get_consumed_snapshot(struct lttng_consumer_stream *stream,
 807                 unsigned long *pos);
 808 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream *stream);
 809 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream *stream);
 810 void *consumer_thread_metadata_poll(void *data);
 811 void *consumer_thread_data_poll(void *data);
 812 void *consumer_thread_sessiond_poll(void *data);
 813 void *consumer_thread_channel_poll(void *data);
 814 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx,
 815                 int sock, struct pollfd *consumer_sockpoll);
 816
 817 ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
 818                 struct lttng_consumer_local_data *ctx);
 819 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream);
 820 void consumer_add_relayd_socket(uint64_t net_seq_idx, int sock_type,
 821                 struct lttng_consumer_local_data *ctx, int sock,
 822                 struct pollfd *consumer_sockpoll, struct lttcomm_relayd_sock *relayd_sock,
 823                 uint64_t sessiond_id, uint64_t relayd_session_id);
 824 void consumer_flag_relayd_for_destroy(
 825                 struct consumer_relayd_sock_pair *relayd);
 826 int consumer_data_pending(uint64_t id);
 827 int consumer_send_status_msg(int sock, int ret_code);
 828 int consumer_send_status_channel(int sock,
 829                 struct lttng_consumer_channel *channel);
 830 void notify_thread_del_channel(struct lttng_consumer_local_data *ctx,
 831                 uint64_t key);
 832 void consumer_destroy_relayd(struct consumer_relayd_sock_pair *relayd);
 833 unsigned long consumer_get_consume_start_pos(unsigned long consumed_pos,
 834                 unsigned long produced_pos, uint64_t nb_packets_per_stream,
 835                 uint64_t max_sb_size);
 836 void consumer_add_data_stream(struct lttng_consumer_stream *stream);
 837 void consumer_del_stream_for_data(struct lttng_consumer_stream *stream);
 838 void consumer_add_metadata_stream(struct lttng_consumer_stream *stream);
 839 void consumer_del_stream_for_metadata(struct lttng_consumer_stream *stream);
 840 int consumer_create_index_file(struct lttng_consumer_stream *stream);
 841 int lttng_consumer_rotate_channel(struct lttng_consumer_channel *channel,
 842                 uint64_t key, const char *path, uint64_t relayd_id,
 843                 uint32_t metadata, uint64_t new_chunk_id,
 844                 struct lttng_consumer_local_data *ctx);
 845 int lttng_consumer_stream_is_rotate_ready(struct lttng_consumer_stream *stream);
 846 int lttng_consumer_rotate_stream(struct lttng_consumer_local_data *ctx,
 847                 struct lttng_consumer_stream *stream, bool *rotated);
 848 int lttng_consumer_rotate_ready_streams(struct lttng_consumer_channel *channel,
 849                 uint64_t key, struct lttng_consumer_local_data *ctx);
 850 int lttng_consumer_rotate_rename(const char *current_path, const char *new_path,
 851                 uid_t uid, gid_t gid, uint64_t relayd_id);
 852 int lttng_consumer_check_rotation_pending_local(uint64_t session_id,
 853                 uint64_t chunk_id);
 854 int lttng_consumer_check_rotation_pending_relay(uint64_t session_id,
 855                 uint64_t relayd_id, uint64_t chunk_id);
 856 void lttng_consumer_reset_stream_rotate_state(struct lttng_consumer_stream *stream);
 857 int lttng_consumer_mkdir(const char *path, uid_t uid, gid_t gid,
 858                 uint64_t relayd_id);
 859 void lttng_consumer_cleanup_relayd(struct consumer_relayd_sock_pair *relayd);
 860
 861 #endif /* LIB_CONSUMER_H */