src/common/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 };
  62
  63 /* State of each fd in consumer */
  64 enum lttng_consumer_stream_state {
  65         LTTNG_CONSUMER_ACTIVE_STREAM,
  66         LTTNG_CONSUMER_PAUSE_STREAM,
  67         LTTNG_CONSUMER_DELETE_STREAM,
  68 };
  69
  70 enum lttng_consumer_type {
  71         LTTNG_CONSUMER_UNKNOWN = 0,
  72         LTTNG_CONSUMER_KERNEL,
  73         LTTNG_CONSUMER64_UST,
  74         LTTNG_CONSUMER32_UST,
  75 };
  76
  77 enum consumer_endpoint_status {
  78         CONSUMER_ENDPOINT_ACTIVE,
  79         CONSUMER_ENDPOINT_INACTIVE,
  80 };
  81
  82 enum consumer_channel_output {
  83         CONSUMER_CHANNEL_MMAP   = 0,
  84         CONSUMER_CHANNEL_SPLICE = 1,
  85 };
  86
  87 enum consumer_channel_type {
  88         CONSUMER_CHANNEL_TYPE_METADATA  = 0,
  89         CONSUMER_CHANNEL_TYPE_DATA      = 1,
  90 };
  91
  92 extern struct lttng_consumer_global_data consumer_data;
  93
  94 struct stream_list {
  95         struct cds_list_head head;
  96         unsigned int count;
  97 };
  98
  99 /* Stub. */
 100 struct consumer_metadata_cache;
 101
 102 struct lttng_consumer_channel {
 103         /* HT node used for consumer_data.channel_ht */
 104         struct lttng_ht_node_u64 node;
 105         /* Indexed key. Incremented value in the consumer. */
 106         uint64_t key;
 107         /* Number of streams referencing this channel */
 108         int refcount;
 109         /* Tracing session id on the session daemon side. */
 110         uint64_t session_id;
 111         /*
 112          * Session id when requesting metadata to the session daemon for
 113          * a session with per-PID buffers.
 114          */
 115         uint64_t session_id_per_pid;
 116         /* Channel trace file path name. */
 117         char pathname[PATH_MAX];
 118         /* Channel name. */
 119         char name[LTTNG_SYMBOL_NAME_LEN];
 120         /* UID and GID of the session owning this channel. */
 121         uid_t uid;
 122         gid_t gid;
 123         /* Relayd id of the channel. -1ULL if it does not apply. */
 124         uint64_t relayd_id;
 125         /*
 126          * Number of streams NOT initialized yet. This is used in order to not
 127          * delete this channel if streams are getting initialized.
 128          */
 129         unsigned int nb_init_stream_left;
 130         /* Output type (mmap or splice). */
 131         enum consumer_channel_output output;
 132         /* Channel type for stream */
 133         enum consumer_channel_type type;
 134
 135         /* For UST */
 136         uid_t ust_app_uid;      /* Application UID. */
 137         struct ustctl_consumer_channel *uchan;
 138         unsigned char uuid[UUID_STR_LEN];
 139         /*
 140          * Temporary stream list used to store the streams once created and waiting
 141          * to be sent to the session daemon by receiving the
 142          * LTTNG_CONSUMER_GET_CHANNEL.
 143          */
 144         struct stream_list streams;
 145
 146         /*
 147          * Set if the channel is metadata. We keep a reference to the stream
 148          * because we have to flush data once pushed by the session daemon. For a
 149          * regular channel, this is always set to NULL.
 150          */
 151         struct lttng_consumer_stream *metadata_stream;
 152
 153         /* for UST */
 154         int wait_fd;
 155         /* Node within channel thread ht */
 156         struct lttng_ht_node_u64 wait_fd_node;
 157
 158         /* Metadata cache is metadata channel */
 159         struct consumer_metadata_cache *metadata_cache;
 160         /* For UST metadata periodical flush */
 161         int switch_timer_enabled;
 162         timer_t switch_timer;
 163         int switch_timer_error;
 164
 165         /* For the live mode */
 166         int live_timer_enabled;
 167         timer_t live_timer;
 168         int live_timer_error;
 169
 170         /* On-disk circular buffer */
 171         uint64_t tracefile_size;
 172         uint64_t tracefile_count;
 173         /*
 174          * Monitor or not the streams of this channel meaning this indicates if the
 175          * streams should be sent to the data/metadata thread or added to the no
 176          * monitor list of the channel.
 177          */
 178         unsigned int monitor;
 179
 180         /*
 181          * Channel lock.
 182          *
 183          * This lock protects against concurrent update of channel.
 184          *
 185          * This is nested INSIDE the consumer data lock.
 186          * This is nested OUTSIDE the channel timer lock.
 187          * This is nested OUTSIDE the metadata cache lock.
 188          * This is nested OUTSIDE stream lock.
 189          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 190          */
 191         pthread_mutex_t lock;
 192
 193         /*
 194          * Channel teardown lock.
 195          *
 196          * This lock protect against teardown of channel. It is _never_
 197          * taken by the timer handler.
 198          *
 199          * This is nested INSIDE the consumer data lock.
 200          * This is nested INSIDE the channel lock.
 201          * This is nested OUTSIDE the metadata cache lock.
 202          * This is nested OUTSIDE stream lock.
 203          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 204          */
 205         pthread_mutex_t timer_lock;
 206
 207         /* Timer value in usec for live streaming. */
 208         unsigned int live_timer_interval;
 209 };
 210
 211 /*
 212  * Internal representation of the streams, sessiond_key is used to identify
 213  * uniquely a stream.
 214  */
 215 struct lttng_consumer_stream {
 216         /* HT node used by the data_ht and metadata_ht */
 217         struct lttng_ht_node_u64 node;
 218         /* stream indexed per channel key node */
 219         struct lttng_ht_node_u64 node_channel_id;
 220         /* HT node used in consumer_data.stream_list_ht */
 221         struct lttng_ht_node_u64 node_session_id;
 222         /* Pointer to associated channel. */
 223         struct lttng_consumer_channel *chan;
 224
 225         /* Key by which the stream is indexed for 'node'. */
 226         uint64_t key;
 227         /*
 228          * File descriptor of the data output file. This can be either a file or a
 229          * socket fd for relayd streaming.
 230          */
 231         int out_fd; /* output file to write the data */
 232         /* Write position in the output file descriptor */
 233         off_t out_fd_offset;
 234         /* Amount of bytes written to the output */
 235         uint64_t output_written;
 236         enum lttng_consumer_stream_state state;
 237         int shm_fd_is_copy;
 238         int data_read;
 239         int hangup_flush_done;
 240
 241         /*
 242          * metadata_timer_lock protects flags waiting_on_metadata and
 243          * missed_metadata_flush.
 244          */
 245         pthread_mutex_t metadata_timer_lock;
 246         /*
 247          * Flag set when awaiting metadata to be pushed. Used in the
 248          * timer thread to skip waiting on the stream (and stream lock) to
 249          * ensure we can proceed to flushing metadata in live mode.
 250          */
 251         bool waiting_on_metadata;
 252         /* Raised when a timer misses a metadata flush. */
 253         bool missed_metadata_flush;
 254
 255         enum lttng_event_output output;
 256         /* Maximum subbuffer size. */
 257         unsigned long max_sb_size;
 258
 259         /*
 260          * Still used by the kernel for MMAP output. For UST, the ustctl getter is
 261          * used for the mmap base and offset.
 262          */
 263         void *mmap_base;
 264         unsigned long mmap_len;
 265
 266         /* For UST */
 267
 268         int wait_fd;
 269         /* UID/GID of the user owning the session to which stream belongs */
 270         uid_t uid;
 271         gid_t gid;
 272         /* Network sequence number. Indicating on which relayd socket it goes. */
 273         uint64_t net_seq_idx;
 274         /*
 275          * Indicate if this stream was successfully sent to a relayd. This is set
 276          * after the refcount of the relayd is incremented and is checked when the
 277          * stream is closed before decrementing the refcount in order to avoid an
 278          * unbalanced state.
 279          */
 280         unsigned int sent_to_relayd;
 281
 282         /* Identify if the stream is the metadata */
 283         unsigned int metadata_flag;
 284         /* Used when the stream is set for network streaming */
 285         uint64_t relayd_stream_id;
 286         /*
 287          * When sending a stream packet to a relayd, this number is used to track
 288          * the packet sent by the consumer and seen by the relayd. When sending the
 289          * data header to the relayd, this number is sent and if the transmission
 290          * was successful, it is incremented.
 291          *
 292          * Even if the full data is not fully transmitted it won't matter since
 293          * only two possible error can happen after that where either the relayd
 294          * died or a read error is detected on the stream making this value useless
 295          * after that.
 296          *
 297          * This value SHOULD be read/updated atomically or with the lock acquired.
 298          */
 299         uint64_t next_net_seq_num;
 300         /*
 301          * Lock to use the stream FDs since they are used between threads.
 302          *
 303          * This is nested INSIDE the consumer_data lock.
 304          * This is nested INSIDE the metadata cache lock.
 305          * This is nested INSIDE the channel lock.
 306          * This is nested INSIDE the channel timer lock.
 307          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 308          */
 309         pthread_mutex_t lock;
 310         /* Tracing session id */
 311         uint64_t session_id;
 312         /*
 313          * Indicates if the stream end point is still active or not (network
 314          * streaming or local file system). The thread "owning" the stream is
 315          * handling this status and can be notified of a state change through the
 316          * consumer data appropriate pipe.
 317          */
 318         enum consumer_endpoint_status endpoint_status;
 319         /* Stream name. Format is: <channel_name>_<cpu_number> */
 320         char name[LTTNG_SYMBOL_NAME_LEN];
 321         /* Internal state of libustctl. */
 322         struct ustctl_consumer_stream *ustream;
 323         struct cds_list_head send_node;
 324         /* On-disk circular buffer */
 325         uint64_t tracefile_size_current;
 326         uint64_t tracefile_count_current;
 327         /*
 328          * Monitor or not the streams of this channel meaning this indicates if the
 329          * streams should be sent to the data/metadata thread or added to the no
 330          * monitor list of the channel.
 331          */
 332         unsigned int monitor;
 333         /*
 334          * Indicate if the stream is globally visible meaning that it has been
 335          * added to the multiple hash tables. If *not* set, NO lock should be
 336          * acquired in the destroy path.
 337          */
 338         unsigned int globally_visible;
 339         /*
 340          * Pipe to wake up the metadata poll thread when the UST metadata
 341          * cache is updated.
 342          */
 343         int ust_metadata_poll_pipe[2];
 344         /*
 345          * How much metadata was read from the metadata cache and sent
 346          * to the channel.
 347          */
 348         uint64_t ust_metadata_pushed;
 349         /*
 350          * FD of the index file for this stream.
 351          */
 352         int index_fd;
 353
 354         /*
 355          * Local pipe to extract data when using splice.
 356          */
 357         int splice_pipe[2];
 358
 359         /*
 360          * Rendez-vous point between data and metadata stream in live mode.
 361          */
 362         pthread_cond_t metadata_rdv;
 363         pthread_mutex_t metadata_rdv_lock;
 364
 365         /* Indicate if the stream still has some data to be read. */
 366         unsigned int has_data:1;
 367 };
 368
 369 /*
 370  * Internal representation of a relayd socket pair.
 371  */
 372 struct consumer_relayd_sock_pair {
 373         /* Network sequence number. */
 374         uint64_t net_seq_idx;
 375         /* Number of stream associated with this relayd */
 376         unsigned int refcount;
 377
 378         /*
 379          * This flag indicates whether or not we should destroy this object. The
 380          * destruction should ONLY occurs when this flag is set and the refcount is
 381          * set to zero.
 382          */
 383         unsigned int destroy_flag;
 384
 385         /*
 386          * Mutex protecting the control socket to avoid out of order packets
 387          * between threads sending data to the relayd. Since metadata data is sent
 388          * over that socket, at least two sendmsg() are needed (header + data)
 389          * creating a race for packets to overlap between threads using it.
 390          *
 391          * This is nested INSIDE the consumer_data lock.
 392          * This is nested INSIDE the stream lock.
 393          */
 394         pthread_mutex_t ctrl_sock_mutex;
 395
 396         /* Control socket. Command and metadata are passed over it */
 397         struct lttcomm_relayd_sock control_sock;
 398
 399         /*
 400          * We don't need a mutex at this point since we only splice or write single
 401          * large chunk of data with a header appended at the begining. Moreover,
 402          * this socket is for now only used in a single thread.
 403          */
 404         struct lttcomm_relayd_sock data_sock;
 405         struct lttng_ht_node_u64 node;
 406
 407         /* Session id on both sides for the sockets. */
 408         uint64_t relayd_session_id;
 409         uint64_t sessiond_session_id;
 410 };
 411
 412 /*
 413  * UST consumer local data to the program. One or more instance per
 414  * process.
 415  */
 416 struct lttng_consumer_local_data {
 417         /*
 418          * Function to call when data is available on a buffer.
 419          * Returns the number of bytes read, or negative error value.
 420          */
 421         ssize_t (*on_buffer_ready)(struct lttng_consumer_stream *stream,
 422                         struct lttng_consumer_local_data *ctx);
 423         /*
 424          * function to call when we receive a new channel, it receives a
 425          * newly allocated channel, depending on the return code of this
 426          * function, the new channel will be handled by the application
 427          * or the library.
 428          *
 429          * Returns:
 430          *    > 0 (success, FD is kept by application)
 431          *   == 0 (success, FD is left to library)
 432          *    < 0 (error)
 433          */
 434         int (*on_recv_channel)(struct lttng_consumer_channel *channel);
 435         /*
 436          * function to call when we receive a new stream, it receives a
 437          * newly allocated stream, depending on the return code of this
 438          * function, the new stream will be handled by the application
 439          * or the library.
 440          *
 441          * Returns:
 442          *    > 0 (success, FD is kept by application)
 443          *   == 0 (success, FD is left to library)
 444          *    < 0 (error)
 445          */
 446         int (*on_recv_stream)(struct lttng_consumer_stream *stream);
 447         /*
 448          * function to call when a stream is getting updated by the session
 449          * daemon, this function receives the sessiond key and the new
 450          * state, depending on the return code of this function the
 451          * update of state for the stream is handled by the application
 452          * or the library.
 453          *
 454          * Returns:
 455          *    > 0 (success, FD is kept by application)
 456          *   == 0 (success, FD is left to library)
 457          *    < 0 (error)
 458          */
 459         int (*on_update_stream)(uint64_t sessiond_key, uint32_t state);
 460         enum lttng_consumer_type type;
 461         /* socket to communicate errors with sessiond */
 462         int consumer_error_socket;
 463         /* socket to ask metadata to sessiond. */
 464         int consumer_metadata_socket;
 465         /*
 466          * Protect consumer_metadata_socket.
 467          *
 468          * This is nested OUTSIDE the metadata cache lock.
 469          */
 470         pthread_mutex_t metadata_socket_lock;
 471         /* socket to exchange commands with sessiond */
 472         char *consumer_command_sock_path;
 473         /* communication with splice */
 474         int consumer_channel_pipe[2];
 475         /* Data stream poll thread pipe. To transfer data stream to the thread */
 476         struct lttng_pipe *consumer_data_pipe;
 477
 478         /*
 479          * Data thread use that pipe to catch wakeup from read subbuffer that
 480          * detects that there is still data to be read for the stream encountered.
 481          * Before doing so, the stream is flagged to indicate that there is still
 482          * data to be read.
 483          *
 484          * Both pipes (read/write) are owned and used inside the data thread.
 485          */
 486         struct lttng_pipe *consumer_wakeup_pipe;
 487         /* Indicate if the wakeup thread has been notified. */
 488         unsigned int has_wakeup:1;
 489
 490         /* to let the signal handler wake up the fd receiver thread */
 491         int consumer_should_quit[2];
 492         /* Metadata poll thread pipe. Transfer metadata stream to it */
 493         struct lttng_pipe *consumer_metadata_pipe;
 494 };
 495
 496 /*
 497  * Library-level data. One instance per process.
 498  */
 499 struct lttng_consumer_global_data {
 500         /*
 501          * At this time, this lock is used to ensure coherence between the count
 502          * and number of element in the hash table. It's also a protection for
 503          * concurrent read/write between threads.
 504          *
 505          * This is nested OUTSIDE the stream lock.
 506          * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
 507          */
 508         pthread_mutex_t lock;
 509
 510         /*
 511          * Number of streams in the data stream hash table declared outside.
 512          * Protected by consumer_data.lock.
 513          */
 514         int stream_count;
 515
 516         /* Channel hash table protected by consumer_data.lock. */
 517         struct lttng_ht *channel_ht;
 518         /*
 519          * Flag specifying if the local array of FDs needs update in the
 520          * poll function. Protected by consumer_data.lock.
 521          */
 522         unsigned int need_update;
 523         enum lttng_consumer_type type;
 524
 525         /*
 526          * Relayd socket(s) hashtable indexed by network sequence number. Each
 527          * stream has an index which associate the right relayd socket to use.
 528          */
 529         struct lttng_ht *relayd_ht;
 530
 531         /*
 532          * This hash table contains all streams (metadata and data) indexed by
 533          * session id. In other words, the ht is indexed by session id and each
 534          * bucket contains the list of associated streams.
 535          *
 536          * This HT uses the "node_session_id" of the consumer stream.
 537          */
 538         struct lttng_ht *stream_list_ht;
 539
 540         /*
 541          * This HT uses the "node_channel_id" of the consumer stream.
 542          */
 543         struct lttng_ht *stream_per_chan_id_ht;
 544 };
 545
 546 /*
 547  * Init consumer data structures.
 548  */
 549 int lttng_consumer_init(void);
 550
 551 /*
 552  * Set the error socket for communication with a session daemon.
 553  */
 554 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data *ctx,
 555                 int sock);
 556
 557 /*
 558  * Set the command socket path for communication with a session daemon.
 559  */
 560 void lttng_consumer_set_command_sock_path(
 561                 struct lttng_consumer_local_data *ctx, char *sock);
 562
 563 /*
 564  * Send return code to session daemon.
 565  *
 566  * Returns the return code of sendmsg : the number of bytes transmitted or -1
 567  * on error.
 568  */
 569 int lttng_consumer_send_error(struct lttng_consumer_local_data *ctx, int cmd);
 570
 571 /*
 572  * Called from signal handler to ensure a clean exit.
 573  */
 574 void lttng_consumer_should_exit(struct lttng_consumer_local_data *ctx);
 575
 576 /*
 577  * Cleanup the daemon's socket on exit.
 578  */
 579 void lttng_consumer_cleanup(void);
 580
 581 /*
 582  * Flush pending writes to trace output disk file.
 583  */
 584 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream *stream,
 585                 off_t orig_offset);
 586
 587 /*
 588  * Poll on the should_quit pipe and the command socket return -1 on error and
 589  * should exit, 0 if data is available on the command socket
 590  */
 591 int lttng_consumer_poll_socket(struct pollfd *kconsumer_sockpoll);
 592
 593 struct lttng_consumer_stream *consumer_allocate_stream(uint64_t channel_key,
 594                 uint64_t stream_key,
 595                 enum lttng_consumer_stream_state state,
 596                 const char *channel_name,
 597                 uid_t uid,
 598                 gid_t gid,
 599                 uint64_t relayd_id,
 600                 uint64_t session_id,
 601                 int cpu,
 602                 int *alloc_ret,
 603                 enum consumer_channel_type type,
 604                 unsigned int monitor);
 605 struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
 606                 uint64_t session_id,
 607                 const char *pathname,
 608                 const char *name,
 609                 uid_t uid,
 610                 gid_t gid,
 611                 uint64_t relayd_id,
 612                 enum lttng_event_output output,
 613                 uint64_t tracefile_size,
 614                 uint64_t tracefile_count,
 615                 uint64_t session_id_per_pid,
 616                 unsigned int monitor,
 617                 unsigned int live_timer_interval);
 618 void consumer_del_stream(struct lttng_consumer_stream *stream,
 619                 struct lttng_ht *ht);
 620 void consumer_del_metadata_stream(struct lttng_consumer_stream *stream,
 621                 struct lttng_ht *ht);
 622 int consumer_add_channel(struct lttng_consumer_channel *channel,
 623                 struct lttng_consumer_local_data *ctx);
 624 void consumer_del_channel(struct lttng_consumer_channel *channel);
 625
 626 /* lttng-relayd consumer command */
 627 struct consumer_relayd_sock_pair *consumer_allocate_relayd_sock_pair(
 628                 uint64_t net_seq_idx);
 629 struct consumer_relayd_sock_pair *consumer_find_relayd(uint64_t key);
 630 int consumer_send_relayd_stream(struct lttng_consumer_stream *stream, char *path);
 631 int consumer_send_relayd_streams_sent(uint64_t net_seq_idx);
 632 void close_relayd_stream(struct lttng_consumer_stream *stream);
 633 struct lttng_consumer_channel *consumer_find_channel(uint64_t key);
 634 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream *stream,
 635                 size_t data_size);
 636 void consumer_steal_stream_key(int key, struct lttng_ht *ht);
 637
 638 struct lttng_consumer_local_data *lttng_consumer_create(
 639                 enum lttng_consumer_type type,
 640                 ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream,
 641                         struct lttng_consumer_local_data *ctx),
 642                 int (*recv_channel)(struct lttng_consumer_channel *channel),
 643                 int (*recv_stream)(struct lttng_consumer_stream *stream),
 644                 int (*update_stream)(uint64_t sessiond_key, uint32_t state));
 645 void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx);
 646 ssize_t lttng_consumer_on_read_subbuffer_mmap(
 647                 struct lttng_consumer_local_data *ctx,
 648                 struct lttng_consumer_stream *stream, unsigned long len,
 649                 unsigned long padding,
 650                 struct ctf_packet_index *index);
 651 ssize_t lttng_consumer_on_read_subbuffer_splice(
 652                 struct lttng_consumer_local_data *ctx,
 653                 struct lttng_consumer_stream *stream, unsigned long len,
 654                 unsigned long padding,
 655                 struct ctf_packet_index *index);
 656 int lttng_consumer_take_snapshot(struct lttng_consumer_stream *stream);
 657 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
 658                 unsigned long *pos);
 659 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream *stream);
 660 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream *stream);
 661 void *consumer_thread_metadata_poll(void *data);
 662 void *consumer_thread_data_poll(void *data);
 663 void *consumer_thread_sessiond_poll(void *data);
 664 void *consumer_thread_channel_poll(void *data);
 665 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx,
 666                 int sock, struct pollfd *consumer_sockpoll);
 667
 668 ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
 669                 struct lttng_consumer_local_data *ctx);
 670 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream);
 671 int consumer_add_relayd_socket(uint64_t net_seq_idx, int sock_type,
 672                 struct lttng_consumer_local_data *ctx, int sock,
 673                 struct pollfd *consumer_sockpoll, struct lttcomm_relayd_sock *relayd_sock,
 674                 uint64_t sessiond_id, uint64_t relayd_session_id);
 675 void consumer_flag_relayd_for_destroy(
 676                 struct consumer_relayd_sock_pair *relayd);
 677 int consumer_data_pending(uint64_t id);
 678 int consumer_send_status_msg(int sock, int ret_code);
 679 int consumer_send_status_channel(int sock,
 680                 struct lttng_consumer_channel *channel);
 681 void notify_thread_del_channel(struct lttng_consumer_local_data *ctx,
 682                 uint64_t key);
 683 void consumer_destroy_relayd(struct consumer_relayd_sock_pair *relayd);
 684 unsigned long consumer_get_consume_start_pos(unsigned long consumed_pos,
 685                 unsigned long produced_pos, uint64_t nb_packets_per_stream,
 686                 uint64_t max_sb_size);
 687 int consumer_add_data_stream(struct lttng_consumer_stream *stream);
 688 void consumer_del_stream_for_data(struct lttng_consumer_stream *stream);
 689 int consumer_add_metadata_stream(struct lttng_consumer_stream *stream);
 690 void consumer_del_stream_for_metadata(struct lttng_consumer_stream *stream);
 691 int consumer_create_index_file(struct lttng_consumer_stream *stream);
 692
 693 #endif /* LIB_CONSUMER_H */