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