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/uuid.h>
  34 #include <common/sessiond-comm/sessiond-comm.h>
  35 #include <common/pipe.h>
  36 #include <common/index/ctf-index.h>
  37 #include <common/trace-chunk-registry.h>
  38 #include <common/credentials.h>
  39
  40 /* Commands for consumer */
  41 enum lttng_consumer_command {
  42         LTTNG_CONSUMER_ADD_CHANNEL,
  43         LTTNG_CONSUMER_ADD_STREAM,
  44         /* pause, delete, active depending on fd state */
  45         LTTNG_CONSUMER_UPDATE_STREAM,
  46         /* inform the consumer to quit when all fd has hang up */
  47         LTTNG_CONSUMER_STOP,    /* deprecated */
  48         LTTNG_CONSUMER_ADD_RELAYD_SOCKET,
  49         /* Inform the consumer to kill a specific relayd connection */
  50         LTTNG_CONSUMER_DESTROY_RELAYD,
  51         /* Return to the sessiond if there is data pending for a session */
  52         LTTNG_CONSUMER_DATA_PENDING,
  53         /* Consumer creates a channel and returns it to sessiond. */
  54         LTTNG_CONSUMER_ASK_CHANNEL_CREATION,
  55         LTTNG_CONSUMER_GET_CHANNEL,
  56         LTTNG_CONSUMER_DESTROY_CHANNEL,
  57         LTTNG_CONSUMER_PUSH_METADATA,
  58         LTTNG_CONSUMER_CLOSE_METADATA,
  59         LTTNG_CONSUMER_SETUP_METADATA,
  60         LTTNG_CONSUMER_FLUSH_CHANNEL,
  61         LTTNG_CONSUMER_SNAPSHOT_CHANNEL,
  62         LTTNG_CONSUMER_SNAPSHOT_METADATA,
  63         LTTNG_CONSUMER_STREAMS_SENT,
  64         LTTNG_CONSUMER_DISCARDED_EVENTS,
  65         LTTNG_CONSUMER_LOST_PACKETS,
  66         LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL,
  67         LTTNG_CONSUMER_SET_CHANNEL_MONITOR_PIPE,
  68         LTTNG_CONSUMER_ROTATE_CHANNEL,
  69         LTTNG_CONSUMER_INIT,
  70         LTTNG_CONSUMER_CREATE_TRACE_CHUNK,
  71         LTTNG_CONSUMER_CLOSE_TRACE_CHUNK,
  72         LTTNG_CONSUMER_TRACE_CHUNK_EXISTS,
  73 };
  74
  75 enum lttng_consumer_type {
  76         LTTNG_CONSUMER_UNKNOWN = 0,
  77         LTTNG_CONSUMER_KERNEL,
  78         LTTNG_CONSUMER64_UST,
  79         LTTNG_CONSUMER32_UST,
  80 };
  81
  82 enum consumer_endpoint_status {
  83         CONSUMER_ENDPOINT_ACTIVE,
  84         CONSUMER_ENDPOINT_INACTIVE,
  85 };
  86
  87 enum consumer_channel_output {
  88         CONSUMER_CHANNEL_MMAP   = 0,
  89         CONSUMER_CHANNEL_SPLICE = 1,
  90 };
  91
  92 enum consumer_channel_type {
  93         CONSUMER_CHANNEL_TYPE_METADATA  = 0,
  94         CONSUMER_CHANNEL_TYPE_DATA      = 1,
  95 };
  96
  97 extern struct lttng_consumer_global_data consumer_data;
  98
  99 struct stream_list {
 100         struct cds_list_head head;
 101         unsigned int count;
 102 };
 103
 104 /* Stub. */
 105 struct consumer_metadata_cache;
 106
 107 struct lttng_consumer_channel {
 108         /* Is the channel published in the channel hash tables? */
 109         bool is_published;
 110         /*
 111          * Was the channel deleted (logically) and waiting to be reclaimed?
 112          * If this flag is set, no modification that is not cleaned-up by the
 113          * RCU reclamation callback should be made
 114          */
 115         bool is_deleted;
 116         /* HT node used for consumer_data.channel_ht */
 117         struct lttng_ht_node_u64 node;
 118         /* HT node used for consumer_data.channels_by_session_id_ht */
 119         struct lttng_ht_node_u64 channels_by_session_id_ht_node;
 120         /* Indexed key. Incremented value in the consumer. */
 121         uint64_t key;
 122         /* Number of streams referencing this channel */
 123         int refcount;
 124         /* Tracing session id on the session daemon side. */
 125         uint64_t session_id;
 126         /* Current trace chunk of the session in which this channel exists. */
 127         struct lttng_trace_chunk *trace_chunk;
 128         /*
 129          * Session id when requesting metadata to the session daemon for
 130          * a session with per-PID buffers.
 131          */
 132         uint64_t session_id_per_pid;
 133         /*
 134          * In the case of local streams, this field contains the channel's
 135          * output path; a path relative to the session's output path.
 136          *   e.g. ust/uid/1000/64-bit
 137          *
 138          * In the case of remote streams, the contents of this field depends
 139          * on the version of the relay daemon peer. For 2.11+ peers, the
 140          * contents are the same as in the local case. However, for legacy
 141          * peers, this contains a path of the form:
 142          *   /hostname/session_path/ust/uid/1000/64-bit
 143          */
 144         char pathname[PATH_MAX];
 145         /* Channel name. */
 146         char name[LTTNG_SYMBOL_NAME_LEN];
 147         /* Relayd id of the channel. -1ULL if it does not apply. */
 148         uint64_t relayd_id;
 149         /*
 150          * Number of streams NOT initialized yet. This is used in order to not
 151          * delete this channel if streams are getting initialized.
 152          */
 153         unsigned int nb_init_stream_left;
 154         /* Output type (mmap or splice). */
 155         enum consumer_channel_output output;
 156         /* Channel type for stream */
 157         enum consumer_channel_type type;
 158
 159         /* For UST */
 160         uid_t ust_app_uid;      /* Application UID. */
 161         struct ustctl_consumer_channel *uchan;
 162         unsigned char uuid[LTTNG_UUID_STR_LEN];
 163         /*
 164          * Temporary stream list used to store the streams once created and waiting
 165          * to be sent to the session daemon by receiving the
 166          * LTTNG_CONSUMER_GET_CHANNEL.
 167          */
 168         struct stream_list streams;
 169
 170         /*
 171          * Set if the channel is metadata. We keep a reference to the stream
 172          * because we have to flush data once pushed by the session daemon. For a
 173          * regular channel, this is always set to NULL.
 174          */
 175         struct lttng_consumer_stream *metadata_stream;
 176
 177         /* for UST */
 178         int wait_fd;
 179         /* Node within channel thread ht */
 180         struct lttng_ht_node_u64 wait_fd_node;
 181
 182         /* Metadata cache is metadata channel */
 183         struct consumer_metadata_cache *metadata_cache;
 184
 185         /* For UST metadata periodical flush */
 186         int switch_timer_enabled;
 187         timer_t switch_timer;
 188         int switch_timer_error;
 189
 190         /* For the live mode */
 191         int live_timer_enabled;
 192         timer_t live_timer;
 193         int live_timer_error;
 194
 195         /* For channel monitoring timer. */
 196         int monitor_timer_enabled;
 197         timer_t monitor_timer;
 198
 199         /* On-disk circular buffer */
 200         uint64_t tracefile_size;
 201         uint64_t tracefile_count;
 202         /*
 203          * Monitor or not the streams of this channel meaning this indicates if the
 204          * streams should be sent to the data/metadata thread or added to the no
 205          * monitor list of the channel.
 206          */
 207         unsigned int monitor;
 208
 209         /*
 210          * Channel lock.
 211          *
 212          * This lock protects against concurrent update of channel.
 213          *
 214          * This is nested INSIDE the consumer data lock.
 215          * This is nested OUTSIDE the channel timer lock.
 216          * This is nested OUTSIDE the metadata cache lock.
 217          * This is nested OUTSIDE stream lock.
 218          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 219          */
 220         pthread_mutex_t lock;
 221
 222         /*
 223          * Channel teardown lock.
 224          *
 225          * This lock protect against teardown of channel. It is _never_
 226          * taken by the timer handler.
 227          *
 228          * This is nested INSIDE the consumer data lock.
 229          * This is nested INSIDE the channel lock.
 230          * This is nested OUTSIDE the metadata cache lock.
 231          * This is nested OUTSIDE stream lock.
 232          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 233          */
 234         pthread_mutex_t timer_lock;
 235
 236         /* Timer value in usec for live streaming. */
 237         unsigned int live_timer_interval;
 238
 239         int *stream_fds;
 240         int nr_stream_fds;
 241         char root_shm_path[PATH_MAX];
 242         char shm_path[PATH_MAX];
 243         /* Only set for UST channels. */
 244         LTTNG_OPTIONAL(struct lttng_credentials) buffer_credentials;
 245         /* Total number of discarded events for that channel. */
 246         uint64_t discarded_events;
 247         /* Total number of missed packets due to overwriting (overwrite). */
 248         uint64_t lost_packets;
 249
 250         bool streams_sent_to_relayd;
 251 };
 252
 253 /*
 254  * Internal representation of the streams, sessiond_key is used to identify
 255  * uniquely a stream.
 256  */
 257 struct lttng_consumer_stream {
 258         /* HT node used by the data_ht and metadata_ht */
 259         struct lttng_ht_node_u64 node;
 260         /* stream indexed per channel key node */
 261         struct lttng_ht_node_u64 node_channel_id;
 262         /* HT node used in consumer_data.stream_list_ht */
 263         struct lttng_ht_node_u64 node_session_id;
 264         /* Pointer to associated channel. */
 265         struct lttng_consumer_channel *chan;
 266         /*
 267          * Current trace chunk. Holds a reference to the trace chunk.
 268          * `chunk` can be NULL when a stream is not associated to a chunk, e.g.
 269          * when it was created in the context of a no-output session.
 270          */
 271         struct lttng_trace_chunk *trace_chunk;
 272
 273         /* Key by which the stream is indexed for 'node'. */
 274         uint64_t key;
 275         /*
 276          * File descriptor of the data output file. This can be either a file or a
 277          * socket fd for relayd streaming.
 278          */
 279         int out_fd; /* output file to write the data */
 280         /* Write position in the output file descriptor */
 281         off_t out_fd_offset;
 282         /* Amount of bytes written to the output */
 283         uint64_t output_written;
 284         int shm_fd_is_copy;
 285         int data_read;
 286         int hangup_flush_done;
 287
 288         /*
 289          * Whether the stream is in a "complete" state (e.g. it does not have a
 290          * partially written sub-buffer.
 291          *
 292          * Initialized to "false" on stream creation (first packet is empty).
 293          *
 294          * The various transitions of the quiescent state are:
 295          *     - On "start" tracing: set to false, since the stream is not
 296          *       "complete".
 297          *     - On "stop" tracing: if !quiescent -> flush FINAL (update
 298          *       timestamp_end), and set to true; the stream has entered a
 299          *       complete/quiescent state.
 300          *     - On "destroy" or stream/application hang-up: if !quiescent ->
 301          *       flush FINAL, and set to true.
 302          *
 303          * NOTE: Update and read are protected by the stream lock.
 304          */
 305         bool quiescent;
 306
 307         /*
 308          * True if the sequence number is not available (lttng-modules < 2.8).
 309          */
 310         bool sequence_number_unavailable;
 311
 312         /*
 313          * metadata_timer_lock protects flags waiting_on_metadata and
 314          * missed_metadata_flush.
 315          */
 316         pthread_mutex_t metadata_timer_lock;
 317         /*
 318          * Flag set when awaiting metadata to be pushed. Used in the
 319          * timer thread to skip waiting on the stream (and stream lock) to
 320          * ensure we can proceed to flushing metadata in live mode.
 321          */
 322         bool waiting_on_metadata;
 323         /* Raised when a timer misses a metadata flush. */
 324         bool missed_metadata_flush;
 325
 326         enum lttng_event_output output;
 327         /* Maximum subbuffer size (in bytes). */
 328         unsigned long max_sb_size;
 329
 330         /*
 331          * Still used by the kernel for MMAP output. For UST, the ustctl getter is
 332          * used for the mmap base and offset.
 333          */
 334         void *mmap_base;
 335         unsigned long mmap_len;
 336
 337         /* For UST */
 338
 339         int wait_fd;
 340         /* Network sequence number. Indicating on which relayd socket it goes. */
 341         uint64_t net_seq_idx;
 342         /*
 343          * Indicate if this stream was successfully sent to a relayd. This is set
 344          * after the refcount of the relayd is incremented and is checked when the
 345          * stream is closed before decrementing the refcount in order to avoid an
 346          * unbalanced state.
 347          */
 348         unsigned int sent_to_relayd;
 349
 350         /* Identify if the stream is the metadata */
 351         unsigned int metadata_flag;
 352         /*
 353          * Last known metadata version, reset the metadata file in case
 354          * of change.
 355          */
 356         uint64_t metadata_version;
 357         /* Used when the stream is set for network streaming */
 358         uint64_t relayd_stream_id;
 359         /*
 360          * When sending a stream packet to a relayd, this number is used to track
 361          * the packet sent by the consumer and seen by the relayd. When sending the
 362          * data header to the relayd, this number is sent and if the transmission
 363          * was successful, it is incremented.
 364          *
 365          * Even if the full data is not fully transmitted it won't matter since
 366          * only two possible error can happen after that where either the relayd
 367          * died or a read error is detected on the stream making this value useless
 368          * after that.
 369          *
 370          * This value SHOULD be read/updated atomically or with the lock acquired.
 371          */
 372         uint64_t next_net_seq_num;
 373         /*
 374          * Lock to use the stream FDs since they are used between threads.
 375          *
 376          * This is nested INSIDE the consumer_data lock.
 377          * This is nested INSIDE the channel lock.
 378          * This is nested INSIDE the channel timer lock.
 379          * This is nested OUTSIDE the metadata cache lock.
 380          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 381          */
 382         pthread_mutex_t lock;
 383         /* Tracing session id */
 384         uint64_t session_id;
 385         /*
 386          * Indicates if the stream end point is still active or not (network
 387          * streaming or local file system). The thread "owning" the stream is
 388          * handling this status and can be notified of a state change through the
 389          * consumer data appropriate pipe.
 390          */
 391         enum consumer_endpoint_status endpoint_status;
 392         /* Stream name. Format is: <channel_name>_<cpu_number> */
 393         char name[LTTNG_SYMBOL_NAME_LEN];
 394         /* Internal state of libustctl. */
 395         struct ustctl_consumer_stream *ustream;
 396         struct cds_list_head send_node;
 397         /* On-disk circular buffer */
 398         uint64_t tracefile_size_current;
 399         uint64_t tracefile_count_current;
 400         /*
 401          * Monitor or not the streams of this channel meaning this indicates if the
 402          * streams should be sent to the data/metadata thread or added to the no
 403          * monitor list of the channel.
 404          */
 405         unsigned int monitor;
 406         /*
 407          * Indicate if the stream is globally visible meaning that it has been
 408          * added to the multiple hash tables. If *not* set, NO lock should be
 409          * acquired in the destroy path.
 410          */
 411         unsigned int globally_visible;
 412         /*
 413          * Pipe to wake up the metadata poll thread when the UST metadata
 414          * cache is updated.
 415          */
 416         int ust_metadata_poll_pipe[2];
 417         /*
 418          * How much metadata was read from the metadata cache and sent
 419          * to the channel.
 420          */
 421         uint64_t ust_metadata_pushed;
 422         /*
 423          * Copy of the last discarded event value to detect the overflow of
 424          * the counter.
 425          */
 426         uint64_t last_discarded_events;
 427         /* Copy of the sequence number of the last packet extracted. */
 428         uint64_t last_sequence_number;
 429         /*
 430          * Index file object of the index file for this stream.
 431          */
 432         struct lttng_index_file *index_file;
 433
 434         /*
 435          * Local pipe to extract data when using splice.
 436          */
 437         int splice_pipe[2];
 438
 439         /*
 440          * Rendez-vous point between data and metadata stream in live mode.
 441          */
 442         pthread_cond_t metadata_rdv;
 443         pthread_mutex_t metadata_rdv_lock;
 444
 445         /*
 446          * rotate_position represents the packet sequence number of the last
 447          * packet which belongs to the current trace chunk prior to the rotation.
 448          * When that position is reached, this tracefile can be closed and a
 449          * new one is created in channel_read_only_attributes.path.
 450          */
 451         uint64_t rotate_position;
 452
 453         /*
 454          * Read-only copies of channel values. We cannot safely access the
 455          * channel from a stream, so we need to have a local copy of these
 456          * fields in the stream object. These fields should be removed from
 457          * the stream objects when we introduce refcounting.
 458          */
 459         struct {
 460                 uint64_t tracefile_size;
 461         } channel_read_only_attributes;
 462
 463         /*
 464          * Flag to inform the data or metadata thread that a stream is
 465          * ready to be rotated.
 466          */
 467         bool rotate_ready;
 468
 469         /* Indicate if the stream still has some data to be read. */
 470         unsigned int has_data:1;
 471         /*
 472          * Inform the consumer or relay to reset the metadata
 473          * file before writing in it (regeneration).
 474          */
 475         unsigned int reset_metadata_flag:1;
 476 };
 477
 478 /*
 479  * Internal representation of a relayd socket pair.
 480  */
 481 struct consumer_relayd_sock_pair {
 482         /* Network sequence number. */
 483         uint64_t net_seq_idx;
 484         /* Number of stream associated with this relayd */
 485         int refcount;
 486
 487         /*
 488          * This flag indicates whether or not we should destroy this object. The
 489          * destruction should ONLY occurs when this flag is set and the refcount is
 490          * set to zero.
 491          */
 492         unsigned int destroy_flag;
 493
 494         /*
 495          * Mutex protecting the control socket to avoid out of order packets
 496          * between threads sending data to the relayd. Since metadata data is sent
 497          * over that socket, at least two sendmsg() are needed (header + data)
 498          * creating a race for packets to overlap between threads using it.
 499          *
 500          * This is nested INSIDE the consumer_data lock.
 501          * This is nested INSIDE the stream lock.
 502          */
 503         pthread_mutex_t ctrl_sock_mutex;
 504
 505         /* Control socket. Command and metadata are passed over it */
 506         struct lttcomm_relayd_sock control_sock;
 507
 508         /*
 509          * We don't need a mutex at this point since we only splice or write single
 510          * large chunk of data with a header appended at the begining. Moreover,
 511          * this socket is for now only used in a single thread.
 512          */
 513         struct lttcomm_relayd_sock data_sock;
 514         struct lttng_ht_node_u64 node;
 515
 516         /* Session id on both sides for the sockets. */
 517         uint64_t relayd_session_id;
 518         uint64_t sessiond_session_id;
 519         struct lttng_consumer_local_data *ctx;
 520 };
 521
 522 /*
 523  * UST consumer local data to the program. One or more instance per
 524  * process.
 525  */
 526 struct lttng_consumer_local_data {
 527         /*
 528          * Function to call when data is available on a buffer.
 529          * Returns the number of bytes read, or negative error value.
 530          */
 531         ssize_t (*on_buffer_ready)(struct lttng_consumer_stream *stream,
 532                         struct lttng_consumer_local_data *ctx);
 533         /*
 534          * function to call when we receive a new channel, it receives a
 535          * newly allocated channel, depending on the return code of this
 536          * function, the new channel will be handled by the application
 537          * or the library.
 538          *
 539          * Returns:
 540          *    > 0 (success, FD is kept by application)
 541          *   == 0 (success, FD is left to library)
 542          *    < 0 (error)
 543          */
 544         int (*on_recv_channel)(struct lttng_consumer_channel *channel);
 545         /*
 546          * function to call when we receive a new stream, it receives a
 547          * newly allocated stream, depending on the return code of this
 548          * function, the new stream will be handled by the application
 549          * or the library.
 550          *
 551          * Returns:
 552          *    > 0 (success, FD is kept by application)
 553          *   == 0 (success, FD is left to library)
 554          *    < 0 (error)
 555          */
 556         int (*on_recv_stream)(struct lttng_consumer_stream *stream);
 557         /*
 558          * function to call when a stream is getting updated by the session
 559          * daemon, this function receives the sessiond key and the new
 560          * state, depending on the return code of this function the
 561          * update of state for the stream is handled by the application
 562          * or the library.
 563          *
 564          * Returns:
 565          *    > 0 (success, FD is kept by application)
 566          *   == 0 (success, FD is left to library)
 567          *    < 0 (error)
 568          */
 569         int (*on_update_stream)(uint64_t sessiond_key, uint32_t state);
 570         enum lttng_consumer_type type;
 571         /* socket to communicate errors with sessiond */
 572         int consumer_error_socket;
 573         /* socket to ask metadata to sessiond. */
 574         int consumer_metadata_socket;
 575         /*
 576          * Protect consumer_metadata_socket.
 577          *
 578          * This is nested OUTSIDE the metadata cache lock.
 579          */
 580         pthread_mutex_t metadata_socket_lock;
 581         /* socket to exchange commands with sessiond */
 582         char *consumer_command_sock_path;
 583         /* communication with splice */
 584         int consumer_channel_pipe[2];
 585         /* Data stream poll thread pipe. To transfer data stream to the thread */
 586         struct lttng_pipe *consumer_data_pipe;
 587
 588         /*
 589          * Data thread use that pipe to catch wakeup from read subbuffer that
 590          * detects that there is still data to be read for the stream encountered.
 591          * Before doing so, the stream is flagged to indicate that there is still
 592          * data to be read.
 593          *
 594          * Both pipes (read/write) are owned and used inside the data thread.
 595          */
 596         struct lttng_pipe *consumer_wakeup_pipe;
 597         /* Indicate if the wakeup thread has been notified. */
 598         unsigned int has_wakeup:1;
 599
 600         /* to let the signal handler wake up the fd receiver thread */
 601         int consumer_should_quit[2];
 602         /* Metadata poll thread pipe. Transfer metadata stream to it */
 603         struct lttng_pipe *consumer_metadata_pipe;
 604         /*
 605          * Pipe used by the channel monitoring timers to provide state samples
 606          * to the session daemon (write-only).
 607          */
 608         int channel_monitor_pipe;
 609         LTTNG_OPTIONAL(lttng_uuid) sessiond_uuid;
 610 };
 611
 612 /*
 613  * Library-level data. One instance per process.
 614  */
 615 struct lttng_consumer_global_data {
 616         /*
 617          * At this time, this lock is used to ensure coherence between the count
 618          * and number of element in the hash table. It's also a protection for
 619          * concurrent read/write between threads.
 620          *
 621          * This is nested OUTSIDE the stream lock.
 622          * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
 623          */
 624         pthread_mutex_t lock;
 625
 626         /*
 627          * Number of streams in the data stream hash table declared outside.
 628          * Protected by consumer_data.lock.
 629          */
 630         int stream_count;
 631
 632         /* Channel hash table protected by consumer_data.lock. */
 633         struct lttng_ht *channel_ht;
 634         /* Channel hash table indexed by session id. */
 635         struct lttng_ht *channels_by_session_id_ht;
 636         /*
 637          * Flag specifying if the local array of FDs needs update in the
 638          * poll function. Protected by consumer_data.lock.
 639          */
 640         unsigned int need_update;
 641         enum lttng_consumer_type type;
 642
 643         /*
 644          * Relayd socket(s) hashtable indexed by network sequence number. Each
 645          * stream has an index which associate the right relayd socket to use.
 646          */
 647         struct lttng_ht *relayd_ht;
 648
 649         /*
 650          * This hash table contains all streams (metadata and data) indexed by
 651          * session id. In other words, the ht is indexed by session id and each
 652          * bucket contains the list of associated streams.
 653          *
 654          * This HT uses the "node_session_id" of the consumer stream.
 655          */
 656         struct lttng_ht *stream_list_ht;
 657
 658         /*
 659          * This HT uses the "node_channel_id" of the consumer stream.
 660          */
 661         struct lttng_ht *stream_per_chan_id_ht;
 662
 663         /*
 664          * Trace chunk registry indexed by (session_id, chunk_id).
 665          */
 666         struct lttng_trace_chunk_registry *chunk_registry;
 667 };
 668
 669 /*
 670  * Set to nonzero when the consumer is exiting. Updated by signal
 671  * handler and thread exit, read by threads.
 672  */
 673 extern int consumer_quit;
 674
 675 /*
 676  * Set to nonzero when the consumer is exiting. Updated by signal
 677  * handler and thread exit, read by threads.
 678  */
 679 extern int consumer_quit;
 680
 681 /* Flag used to temporarily pause data consumption from testpoints. */
 682 extern int data_consumption_paused;
 683
 684 /* Return a human-readable consumer type string that is suitable for logging. */
 685 static inline
 686 const char *lttng_consumer_type_str(enum lttng_consumer_type type)
 687 {
 688         switch (type) {
 689         case LTTNG_CONSUMER_UNKNOWN:
 690                 return "unknown";
 691         case LTTNG_CONSUMER_KERNEL:
 692                 return "kernel";
 693         case LTTNG_CONSUMER32_UST:
 694                 return "32-bit user space";
 695         case LTTNG_CONSUMER64_UST:
 696                 return "64-bit user space";
 697         default:
 698                 abort();
 699         }
 700 }
 701
 702 /*
 703  * Init consumer data structures.
 704  */
 705 int lttng_consumer_init(void);
 706
 707 /*
 708  * Set the error socket for communication with a session daemon.
 709  */
 710 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data *ctx,
 711                 int sock);
 712
 713 /*
 714  * Set the command socket path for communication with a session daemon.
 715  */
 716 void lttng_consumer_set_command_sock_path(
 717                 struct lttng_consumer_local_data *ctx, char *sock);
 718
 719 /*
 720  * Send return code to session daemon.
 721  *
 722  * Returns the return code of sendmsg : the number of bytes transmitted or -1
 723  * on error.
 724  */
 725 int lttng_consumer_send_error(struct lttng_consumer_local_data *ctx, int cmd);
 726
 727 /*
 728  * Called from signal handler to ensure a clean exit.
 729  */
 730 void lttng_consumer_should_exit(struct lttng_consumer_local_data *ctx);
 731
 732 /*
 733  * Cleanup the daemon's socket on exit.
 734  */
 735 void lttng_consumer_cleanup(void);
 736
 737 /*
 738  * Poll on the should_quit pipe and the command socket return -1 on error and
 739  * should exit, 0 if data is available on the command socket
 740  */
 741 int lttng_consumer_poll_socket(struct pollfd *kconsumer_sockpoll);
 742
 743 /*
 744  * Copy the fields from the channel that need to be accessed (read-only)
 745  * directly from the stream.
 746  */
 747 void consumer_stream_update_channel_attributes(
 748                 struct lttng_consumer_stream *stream,
 749                 struct lttng_consumer_channel *channel);
 750
 751 struct lttng_consumer_stream *consumer_allocate_stream(uint64_t channel_key,
 752                 uint64_t stream_key,
 753                 const char *channel_name,
 754                 uint64_t relayd_id,
 755                 uint64_t session_id,
 756                 struct lttng_trace_chunk *trace_chunk,
 757                 int cpu,
 758                 int *alloc_ret,
 759                 enum consumer_channel_type type,
 760                 unsigned int monitor);
 761 struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
 762                 uint64_t session_id,
 763                 const uint64_t *chunk_id,
 764                 const char *pathname,
 765                 const char *name,
 766                 uint64_t relayd_id,
 767                 enum lttng_event_output output,
 768                 uint64_t tracefile_size,
 769                 uint64_t tracefile_count,
 770                 uint64_t session_id_per_pid,
 771                 unsigned int monitor,
 772                 unsigned int live_timer_interval,
 773                 const char *root_shm_path,
 774                 const char *shm_path);
 775 void consumer_del_stream(struct lttng_consumer_stream *stream,
 776                 struct lttng_ht *ht);
 777 void consumer_del_metadata_stream(struct lttng_consumer_stream *stream,
 778                 struct lttng_ht *ht);
 779 int consumer_add_channel(struct lttng_consumer_channel *channel,
 780                 struct lttng_consumer_local_data *ctx);
 781 void consumer_del_channel(struct lttng_consumer_channel *channel);
 782
 783 /* lttng-relayd consumer command */
 784 struct consumer_relayd_sock_pair *consumer_find_relayd(uint64_t key);
 785 int consumer_send_relayd_stream(struct lttng_consumer_stream *stream, char *path);
 786 int consumer_send_relayd_streams_sent(uint64_t net_seq_idx);
 787 void close_relayd_stream(struct lttng_consumer_stream *stream);
 788 struct lttng_consumer_channel *consumer_find_channel(uint64_t key);
 789 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream *stream,
 790                 size_t data_size);
 791 void consumer_steal_stream_key(int key, struct lttng_ht *ht);
 792
 793 struct lttng_consumer_local_data *lttng_consumer_create(
 794                 enum lttng_consumer_type type,
 795                 ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream,
 796                         struct lttng_consumer_local_data *ctx),
 797                 int (*recv_channel)(struct lttng_consumer_channel *channel),
 798                 int (*recv_stream)(struct lttng_consumer_stream *stream),
 799                 int (*update_stream)(uint64_t sessiond_key, uint32_t state));
 800 void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx);
 801 ssize_t lttng_consumer_on_read_subbuffer_mmap(
 802                 struct lttng_consumer_local_data *ctx,
 803                 struct lttng_consumer_stream *stream, unsigned long len,
 804                 unsigned long padding,
 805                 struct ctf_packet_index *index);
 806 ssize_t lttng_consumer_on_read_subbuffer_splice(
 807                 struct lttng_consumer_local_data *ctx,
 808                 struct lttng_consumer_stream *stream, unsigned long len,
 809                 unsigned long padding,
 810                 struct ctf_packet_index *index);
 811 int lttng_consumer_sample_snapshot_positions(struct lttng_consumer_stream *stream);
 812 int lttng_consumer_take_snapshot(struct lttng_consumer_stream *stream);
 813 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
 814                 unsigned long *pos);
 815 int lttng_consumer_get_consumed_snapshot(struct lttng_consumer_stream *stream,
 816                 unsigned long *pos);
 817 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream *stream);
 818 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream *stream);
 819 void *consumer_thread_metadata_poll(void *data);
 820 void *consumer_thread_data_poll(void *data);
 821 void *consumer_thread_sessiond_poll(void *data);
 822 void *consumer_thread_channel_poll(void *data);
 823 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx,
 824                 int sock, struct pollfd *consumer_sockpoll);
 825
 826 ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
 827                 struct lttng_consumer_local_data *ctx);
 828 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream);
 829 void consumer_add_relayd_socket(uint64_t net_seq_idx, int sock_type,
 830                 struct lttng_consumer_local_data *ctx, int sock,
 831                 struct pollfd *consumer_sockpoll, struct lttcomm_relayd_sock *relayd_sock,
 832                 uint64_t sessiond_id, uint64_t relayd_session_id);
 833 void consumer_flag_relayd_for_destroy(
 834                 struct consumer_relayd_sock_pair *relayd);
 835 int consumer_data_pending(uint64_t id);
 836 int consumer_send_status_msg(int sock, int ret_code);
 837 int consumer_send_status_channel(int sock,
 838                 struct lttng_consumer_channel *channel);
 839 void notify_thread_del_channel(struct lttng_consumer_local_data *ctx,
 840                 uint64_t key);
 841 void consumer_destroy_relayd(struct consumer_relayd_sock_pair *relayd);
 842 unsigned long consumer_get_consume_start_pos(unsigned long consumed_pos,
 843                 unsigned long produced_pos, uint64_t nb_packets_per_stream,
 844                 uint64_t max_sb_size);
 845 void consumer_add_data_stream(struct lttng_consumer_stream *stream);
 846 void consumer_del_stream_for_data(struct lttng_consumer_stream *stream);
 847 void consumer_add_metadata_stream(struct lttng_consumer_stream *stream);
 848 void consumer_del_stream_for_metadata(struct lttng_consumer_stream *stream);
 849 int consumer_create_index_file(struct lttng_consumer_stream *stream);
 850 int lttng_consumer_rotate_channel(struct lttng_consumer_channel *channel,
 851                 uint64_t key, uint64_t relayd_id, uint32_t metadata,
 852                 struct lttng_consumer_local_data *ctx);
 853 int lttng_consumer_stream_is_rotate_ready(struct lttng_consumer_stream *stream);
 854 int lttng_consumer_rotate_stream(struct lttng_consumer_local_data *ctx,
 855                 struct lttng_consumer_stream *stream);
 856 int lttng_consumer_rotate_ready_streams(struct lttng_consumer_channel *channel,
 857                 uint64_t key, struct lttng_consumer_local_data *ctx);
 858 void lttng_consumer_reset_stream_rotate_state(struct lttng_consumer_stream *stream);
 859 enum lttcomm_return_code lttng_consumer_create_trace_chunk(
 860                 const uint64_t *relayd_id, uint64_t session_id,
 861                 uint64_t chunk_id,
 862                 time_t chunk_creation_timestamp,
 863                 const char *chunk_override_name,
 864                 const struct lttng_credentials *credentials,
 865                 struct lttng_directory_handle *chunk_directory_handle);
 866 enum lttcomm_return_code lttng_consumer_close_trace_chunk(
 867                 const uint64_t *relayd_id, uint64_t session_id,
 868                 uint64_t chunk_id, time_t chunk_close_timestamp,
 869                 const enum lttng_trace_chunk_command_type *close_command,
 870                 char *path);
 871 enum lttcomm_return_code lttng_consumer_trace_chunk_exists(
 872                 const uint64_t *relayd_id, uint64_t session_id,
 873                 uint64_t chunk_id);
 874 void lttng_consumer_cleanup_relayd(struct consumer_relayd_sock_pair *relayd);
 875 enum lttcomm_return_code lttng_consumer_init_command(
 876                 struct lttng_consumer_local_data *ctx,
 877                 const lttng_uuid sessiond_uuid);
 878
 879 #endif /* LIB_CONSUMER_H */