src/common/consumer/consumer.h

   1 /*
   2  * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
   3  *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *               2012 - David Goulet <dgoulet@efficios.com>
   5  *               2018 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License, version 2 only,
   9  * as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  14  * more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #ifndef LIB_CONSUMER_H
  22 #define LIB_CONSUMER_H
  23
  24 #include <limits.h>
  25 #include <poll.h>
  26 #include <unistd.h>
  27 #include <urcu/list.h>
  28
  29 #include <lttng/lttng.h>
  30
  31 #include <common/hashtable/hashtable.h>
  32 #include <common/compat/fcntl.h>
  33 #include <common/compat/uuid.h>
  34 #include <common/sessiond-comm/sessiond-comm.h>
  35 #include <common/pipe.h>
  36 #include <common/index/ctf-index.h>
  37 #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         /* HT node used for consumer_data.channel_ht */
 111         struct lttng_ht_node_u64 node;
 112         /* HT node used for consumer_data.channels_by_session_id_ht */
 113         struct lttng_ht_node_u64 channels_by_session_id_ht_node;
 114         /* Indexed key. Incremented value in the consumer. */
 115         uint64_t key;
 116         /* Number of streams referencing this channel */
 117         int refcount;
 118         /* Tracing session id on the session daemon side. */
 119         uint64_t session_id;
 120         /* Current trace chunk of the session in which this channel exists. */
 121         struct lttng_trace_chunk *trace_chunk;
 122         /*
 123          * Session id when requesting metadata to the session daemon for
 124          * a session with per-PID buffers.
 125          */
 126         uint64_t session_id_per_pid;
 127         /*
 128          * In the case of local streams, this field contains the channel's
 129          * output path; a path relative to the session's output path.
 130          *   e.g. ust/uid/1000/64-bit
 131          *
 132          * In the case of remote streams, the contents of this field depends
 133          * on the version of the relay daemon peer. For 2.11+ peers, the
 134          * contents are the same as in the local case. However, for legacy
 135          * peers, this contains a path of the form:
 136          *   /hostname/session_path/ust/uid/1000/64-bit
 137          */
 138         char pathname[PATH_MAX];
 139         /* Channel name. */
 140         char name[LTTNG_SYMBOL_NAME_LEN];
 141         /* Relayd id of the channel. -1ULL if it does not apply. */
 142         uint64_t relayd_id;
 143         /*
 144          * Number of streams NOT initialized yet. This is used in order to not
 145          * delete this channel if streams are getting initialized.
 146          */
 147         unsigned int nb_init_stream_left;
 148         /* Output type (mmap or splice). */
 149         enum consumer_channel_output output;
 150         /* Channel type for stream */
 151         enum consumer_channel_type type;
 152
 153         /* For UST */
 154         uid_t ust_app_uid;      /* Application UID. */
 155         struct ustctl_consumer_channel *uchan;
 156         unsigned char uuid[UUID_STR_LEN];
 157         /*
 158          * Temporary stream list used to store the streams once created and waiting
 159          * to be sent to the session daemon by receiving the
 160          * LTTNG_CONSUMER_GET_CHANNEL.
 161          */
 162         struct stream_list streams;
 163
 164         /*
 165          * Set if the channel is metadata. We keep a reference to the stream
 166          * because we have to flush data once pushed by the session daemon. For a
 167          * regular channel, this is always set to NULL.
 168          */
 169         struct lttng_consumer_stream *metadata_stream;
 170
 171         /* for UST */
 172         int wait_fd;
 173         /* Node within channel thread ht */
 174         struct lttng_ht_node_u64 wait_fd_node;
 175
 176         /* Metadata cache is metadata channel */
 177         struct consumer_metadata_cache *metadata_cache;
 178
 179         /* For UST metadata periodical flush */
 180         int switch_timer_enabled;
 181         timer_t switch_timer;
 182         int switch_timer_error;
 183
 184         /* For the live mode */
 185         int live_timer_enabled;
 186         timer_t live_timer;
 187         int live_timer_error;
 188
 189         /* For channel monitoring timer. */
 190         int monitor_timer_enabled;
 191         timer_t monitor_timer;
 192
 193         /* On-disk circular buffer */
 194         uint64_t tracefile_size;
 195         uint64_t tracefile_count;
 196         /*
 197          * Monitor or not the streams of this channel meaning this indicates if the
 198          * streams should be sent to the data/metadata thread or added to the no
 199          * monitor list of the channel.
 200          */
 201         unsigned int monitor;
 202
 203         /*
 204          * Channel lock.
 205          *
 206          * This lock protects against concurrent update of channel.
 207          *
 208          * This is nested INSIDE the consumer data lock.
 209          * This is nested OUTSIDE the channel timer lock.
 210          * This is nested OUTSIDE the metadata cache lock.
 211          * This is nested OUTSIDE stream lock.
 212          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 213          */
 214         pthread_mutex_t lock;
 215
 216         /*
 217          * Channel teardown lock.
 218          *
 219          * This lock protect against teardown of channel. It is _never_
 220          * taken by the timer handler.
 221          *
 222          * This is nested INSIDE the consumer data lock.
 223          * This is nested INSIDE the channel lock.
 224          * This is nested OUTSIDE the metadata cache lock.
 225          * This is nested OUTSIDE stream lock.
 226          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 227          */
 228         pthread_mutex_t timer_lock;
 229
 230         /* Timer value in usec for live streaming. */
 231         unsigned int live_timer_interval;
 232
 233         int *stream_fds;
 234         int nr_stream_fds;
 235         char root_shm_path[PATH_MAX];
 236         char shm_path[PATH_MAX];
 237         /* Only set for UST channels. */
 238         LTTNG_OPTIONAL(struct lttng_credentials) buffer_credentials;
 239         /* Total number of discarded events for that channel. */
 240         uint64_t discarded_events;
 241         /* Total number of missed packets due to overwriting (overwrite). */
 242         uint64_t lost_packets;
 243
 244         bool streams_sent_to_relayd;
 245 };
 246
 247 /*
 248  * Internal representation of the streams, sessiond_key is used to identify
 249  * uniquely a stream.
 250  */
 251 struct lttng_consumer_stream {
 252         /* HT node used by the data_ht and metadata_ht */
 253         struct lttng_ht_node_u64 node;
 254         /* stream indexed per channel key node */
 255         struct lttng_ht_node_u64 node_channel_id;
 256         /* HT node used in consumer_data.stream_list_ht */
 257         struct lttng_ht_node_u64 node_session_id;
 258         /* Pointer to associated channel. */
 259         struct lttng_consumer_channel *chan;
 260         /*
 261          * Current trace chunk. Holds a reference to the trace chunk.
 262          * `chunk` can be NULL when a stream is not associated to a chunk, e.g.
 263          * when it was created in the context of a no-output session.
 264          */
 265         struct lttng_trace_chunk *trace_chunk;
 266
 267         /* Key by which the stream is indexed for 'node'. */
 268         uint64_t key;
 269         /*
 270          * File descriptor of the data output file. This can be either a file or a
 271          * socket fd for relayd streaming.
 272          */
 273         int out_fd; /* output file to write the data */
 274         /* Write position in the output file descriptor */
 275         off_t out_fd_offset;
 276         /* Amount of bytes written to the output */
 277         uint64_t output_written;
 278         int shm_fd_is_copy;
 279         int data_read;
 280         int hangup_flush_done;
 281
 282         /*
 283          * Whether the stream is in a "complete" state (e.g. it does not have a
 284          * partially written sub-buffer.
 285          *
 286          * Initialized to "false" on stream creation (first packet is empty).
 287          *
 288          * The various transitions of the quiescent state are:
 289          *     - On "start" tracing: set to false, since the stream is not
 290          *       "complete".
 291          *     - On "stop" tracing: if !quiescent -> flush FINAL (update
 292          *       timestamp_end), and set to true; the stream has entered a
 293          *       complete/quiescent state.
 294          *     - On "destroy" or stream/application hang-up: if !quiescent ->
 295          *       flush FINAL, and set to true.
 296          *
 297          * NOTE: Update and read are protected by the stream lock.
 298          */
 299         bool quiescent;
 300
 301         /*
 302          * metadata_timer_lock protects flags waiting_on_metadata and
 303          * missed_metadata_flush.
 304          */
 305         pthread_mutex_t metadata_timer_lock;
 306         /*
 307          * Flag set when awaiting metadata to be pushed. Used in the
 308          * timer thread to skip waiting on the stream (and stream lock) to
 309          * ensure we can proceed to flushing metadata in live mode.
 310          */
 311         bool waiting_on_metadata;
 312         /* Raised when a timer misses a metadata flush. */
 313         bool missed_metadata_flush;
 314
 315         enum lttng_event_output output;
 316         /* Maximum subbuffer size. */
 317         unsigned long max_sb_size;
 318
 319         /*
 320          * Still used by the kernel for MMAP output. For UST, the ustctl getter is
 321          * used for the mmap base and offset.
 322          */
 323         void *mmap_base;
 324         unsigned long mmap_len;
 325
 326         /* For UST */
 327
 328         int wait_fd;
 329         /* Network sequence number. Indicating on which relayd socket it goes. */
 330         uint64_t net_seq_idx;
 331         /*
 332          * Indicate if this stream was successfully sent to a relayd. This is set
 333          * after the refcount of the relayd is incremented and is checked when the
 334          * stream is closed before decrementing the refcount in order to avoid an
 335          * unbalanced state.
 336          */
 337         unsigned int sent_to_relayd;
 338
 339         /* Identify if the stream is the metadata */
 340         unsigned int metadata_flag;
 341         /*
 342          * Last known metadata version, reset the metadata file in case
 343          * of change.
 344          */
 345         uint64_t metadata_version;
 346         /* Used when the stream is set for network streaming */
 347         uint64_t relayd_stream_id;
 348         /*
 349          * When sending a stream packet to a relayd, this number is used to track
 350          * the packet sent by the consumer and seen by the relayd. When sending the
 351          * data header to the relayd, this number is sent and if the transmission
 352          * was successful, it is incremented.
 353          *
 354          * Even if the full data is not fully transmitted it won't matter since
 355          * only two possible error can happen after that where either the relayd
 356          * died or a read error is detected on the stream making this value useless
 357          * after that.
 358          *
 359          * This value SHOULD be read/updated atomically or with the lock acquired.
 360          */
 361         uint64_t next_net_seq_num;
 362         /*
 363          * Lock to use the stream FDs since they are used between threads.
 364          *
 365          * This is nested INSIDE the consumer_data lock.
 366          * This is nested INSIDE the channel lock.
 367          * This is nested INSIDE the channel timer lock.
 368          * This is nested OUTSIDE the metadata cache lock.
 369          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 370          */
 371         pthread_mutex_t lock;
 372         /* Tracing session id */
 373         uint64_t session_id;
 374         /*
 375          * Indicates if the stream end point is still active or not (network
 376          * streaming or local file system). The thread "owning" the stream is
 377          * handling this status and can be notified of a state change through the
 378          * consumer data appropriate pipe.
 379          */
 380         enum consumer_endpoint_status endpoint_status;
 381         /* Stream name. Format is: <channel_name>_<cpu_number> */
 382         char name[LTTNG_SYMBOL_NAME_LEN];
 383         /* Internal state of libustctl. */
 384         struct ustctl_consumer_stream *ustream;
 385         struct cds_list_head send_node;
 386         /* On-disk circular buffer */
 387         uint64_t tracefile_size_current;
 388         uint64_t tracefile_count_current;
 389         /*
 390          * Monitor or not the streams of this channel meaning this indicates if the
 391          * streams should be sent to the data/metadata thread or added to the no
 392          * monitor list of the channel.
 393          */
 394         unsigned int monitor;
 395         /*
 396          * Indicate if the stream is globally visible meaning that it has been
 397          * added to the multiple hash tables. If *not* set, NO lock should be
 398          * acquired in the destroy path.
 399          */
 400         unsigned int globally_visible;
 401         /*
 402          * Pipe to wake up the metadata poll thread when the UST metadata
 403          * cache is updated.
 404          */
 405         int ust_metadata_poll_pipe[2];
 406         /*
 407          * How much metadata was read from the metadata cache and sent
 408          * to the channel.
 409          */
 410         uint64_t ust_metadata_pushed;
 411         /*
 412          * Copy of the last discarded event value to detect the overflow of
 413          * the counter.
 414          */
 415         uint64_t last_discarded_events;
 416         /* Copy of the sequence number of the last packet extracted. */
 417         uint64_t last_sequence_number;
 418         /*
 419          * Index file object of the index file for this stream.
 420          */
 421         struct lttng_index_file *index_file;
 422
 423         /*
 424          * Local pipe to extract data when using splice.
 425          */
 426         int splice_pipe[2];
 427
 428         /*
 429          * Rendez-vous point between data and metadata stream in live mode.
 430          */
 431         pthread_cond_t metadata_rdv;
 432         pthread_mutex_t metadata_rdv_lock;
 433
 434         /*
 435          * rotate_position represents the position in the ring-buffer that has to
 436          * be flushed to disk to complete the ongoing rotation. When that position
 437          * is reached, this tracefile can be closed and a new one is created in
 438          * channel_read_only_attributes.path.
 439          */
 440         unsigned long rotate_position;
 441
 442         /*
 443          * Read-only copies of channel values. We cannot safely access the
 444          * channel from a stream, so we need to have a local copy of these
 445          * fields in the stream object. These fields should be removed from
 446          * the stream objects when we introduce refcounting.
 447          */
 448         struct {
 449                 uint64_t tracefile_size;
 450         } channel_read_only_attributes;
 451
 452         /*
 453          * Flag to inform the data or metadata thread that a stream is
 454          * ready to be rotated.
 455          */
 456         bool rotate_ready;
 457
 458         /* Indicate if the stream still has some data to be read. */
 459         unsigned int has_data:1;
 460         /*
 461          * Inform the consumer or relay to reset the metadata
 462          * file before writing in it (regeneration).
 463          */
 464         unsigned int reset_metadata_flag:1;
 465 };
 466
 467 /*
 468  * Internal representation of a relayd socket pair.
 469  */
 470 struct consumer_relayd_sock_pair {
 471         /* Network sequence number. */
 472         uint64_t net_seq_idx;
 473         /* Number of stream associated with this relayd */
 474         int refcount;
 475
 476         /*
 477          * This flag indicates whether or not we should destroy this object. The
 478          * destruction should ONLY occurs when this flag is set and the refcount is
 479          * set to zero.
 480          */
 481         unsigned int destroy_flag;
 482
 483         /*
 484          * Mutex protecting the control socket to avoid out of order packets
 485          * between threads sending data to the relayd. Since metadata data is sent
 486          * over that socket, at least two sendmsg() are needed (header + data)
 487          * creating a race for packets to overlap between threads using it.
 488          *
 489          * This is nested INSIDE the consumer_data lock.
 490          * This is nested INSIDE the stream lock.
 491          */
 492         pthread_mutex_t ctrl_sock_mutex;
 493
 494         /* Control socket. Command and metadata are passed over it */
 495         struct lttcomm_relayd_sock control_sock;
 496
 497         /*
 498          * We don't need a mutex at this point since we only splice or write single
 499          * large chunk of data with a header appended at the begining. Moreover,
 500          * this socket is for now only used in a single thread.
 501          */
 502         struct lttcomm_relayd_sock data_sock;
 503         struct lttng_ht_node_u64 node;
 504
 505         /* Session id on both sides for the sockets. */
 506         uint64_t relayd_session_id;
 507         uint64_t sessiond_session_id;
 508         struct lttng_consumer_local_data *ctx;
 509 };
 510
 511 /*
 512  * UST consumer local data to the program. One or more instance per
 513  * process.
 514  */
 515 struct lttng_consumer_local_data {
 516         /*
 517          * Function to call when data is available on a buffer.
 518          * Returns the number of bytes read, or negative error value.
 519          */
 520         ssize_t (*on_buffer_ready)(struct lttng_consumer_stream *stream,
 521                         struct lttng_consumer_local_data *ctx);
 522         /*
 523          * function to call when we receive a new channel, it receives a
 524          * newly allocated channel, depending on the return code of this
 525          * function, the new channel will be handled by the application
 526          * or the library.
 527          *
 528          * Returns:
 529          *    > 0 (success, FD is kept by application)
 530          *   == 0 (success, FD is left to library)
 531          *    < 0 (error)
 532          */
 533         int (*on_recv_channel)(struct lttng_consumer_channel *channel);
 534         /*
 535          * function to call when we receive a new stream, it receives a
 536          * newly allocated stream, depending on the return code of this
 537          * function, the new stream will be handled by the application
 538          * or the library.
 539          *
 540          * Returns:
 541          *    > 0 (success, FD is kept by application)
 542          *   == 0 (success, FD is left to library)
 543          *    < 0 (error)
 544          */
 545         int (*on_recv_stream)(struct lttng_consumer_stream *stream);
 546         /*
 547          * function to call when a stream is getting updated by the session
 548          * daemon, this function receives the sessiond key and the new
 549          * state, depending on the return code of this function the
 550          * update of state for the stream is handled by the application
 551          * or the library.
 552          *
 553          * Returns:
 554          *    > 0 (success, FD is kept by application)
 555          *   == 0 (success, FD is left to library)
 556          *    < 0 (error)
 557          */
 558         int (*on_update_stream)(uint64_t sessiond_key, uint32_t state);
 559         enum lttng_consumer_type type;
 560         /* socket to communicate errors with sessiond */
 561         int consumer_error_socket;
 562         /* socket to ask metadata to sessiond. */
 563         int consumer_metadata_socket;
 564         /*
 565          * Protect consumer_metadata_socket.
 566          *
 567          * This is nested OUTSIDE the metadata cache lock.
 568          */
 569         pthread_mutex_t metadata_socket_lock;
 570         /* socket to exchange commands with sessiond */
 571         char *consumer_command_sock_path;
 572         /* communication with splice */
 573         int consumer_channel_pipe[2];
 574         /* Data stream poll thread pipe. To transfer data stream to the thread */
 575         struct lttng_pipe *consumer_data_pipe;
 576
 577         /*
 578          * Data thread use that pipe to catch wakeup from read subbuffer that
 579          * detects that there is still data to be read for the stream encountered.
 580          * Before doing so, the stream is flagged to indicate that there is still
 581          * data to be read.
 582          *
 583          * Both pipes (read/write) are owned and used inside the data thread.
 584          */
 585         struct lttng_pipe *consumer_wakeup_pipe;
 586         /* Indicate if the wakeup thread has been notified. */
 587         unsigned int has_wakeup:1;
 588
 589         /* to let the signal handler wake up the fd receiver thread */
 590         int consumer_should_quit[2];
 591         /* Metadata poll thread pipe. Transfer metadata stream to it */
 592         struct lttng_pipe *consumer_metadata_pipe;
 593         /*
 594          * Pipe used by the channel monitoring timers to provide state samples
 595          * to the session daemon (write-only).
 596          */
 597         int channel_monitor_pipe;
 598         LTTNG_OPTIONAL(lttng_uuid) sessiond_uuid;
 599 };
 600
 601 /*
 602  * Library-level data. One instance per process.
 603  */
 604 struct lttng_consumer_global_data {
 605         /*
 606          * At this time, this lock is used to ensure coherence between the count
 607          * and number of element in the hash table. It's also a protection for
 608          * concurrent read/write between threads.
 609          *
 610          * This is nested OUTSIDE the stream lock.
 611          * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
 612          */
 613         pthread_mutex_t lock;
 614
 615         /*
 616          * Number of streams in the data stream hash table declared outside.
 617          * Protected by consumer_data.lock.
 618          */
 619         int stream_count;
 620
 621         /* Channel hash table protected by consumer_data.lock. */
 622         struct lttng_ht *channel_ht;
 623         /* Channel hash table indexed by session id. */
 624         struct lttng_ht *channels_by_session_id_ht;
 625         /*
 626          * Flag specifying if the local array of FDs needs update in the
 627          * poll function. Protected by consumer_data.lock.
 628          */
 629         unsigned int need_update;
 630         enum lttng_consumer_type type;
 631
 632         /*
 633          * Relayd socket(s) hashtable indexed by network sequence number. Each
 634          * stream has an index which associate the right relayd socket to use.
 635          */
 636         struct lttng_ht *relayd_ht;
 637
 638         /*
 639          * This hash table contains all streams (metadata and data) indexed by
 640          * session id. In other words, the ht is indexed by session id and each
 641          * bucket contains the list of associated streams.
 642          *
 643          * This HT uses the "node_session_id" of the consumer stream.
 644          */
 645         struct lttng_ht *stream_list_ht;
 646
 647         /*
 648          * This HT uses the "node_channel_id" of the consumer stream.
 649          */
 650         struct lttng_ht *stream_per_chan_id_ht;
 651
 652         /*
 653          * Trace chunk registry indexed by (session_id, chunk_id).
 654          */
 655         struct lttng_trace_chunk_registry *chunk_registry;
 656 };
 657
 658 /*
 659  * Set to nonzero when the consumer is exiting. Updated by signal
 660  * handler and thread exit, read by threads.
 661  */
 662 extern int consumer_quit;
 663
 664 /*
 665  * Set to nonzero when the consumer is exiting. Updated by signal
 666  * handler and thread exit, read by threads.
 667  */
 668 extern int consumer_quit;
 669
 670 /* Flag used to temporarily pause data consumption from testpoints. */
 671 extern int data_consumption_paused;
 672
 673 /* Return a human-readable consumer type string that is suitable for logging. */
 674 static inline
 675 const char *lttng_consumer_type_str(enum lttng_consumer_type type)
 676 {
 677         switch (type) {
 678         case LTTNG_CONSUMER_UNKNOWN:
 679                 return "unknown";
 680         case LTTNG_CONSUMER_KERNEL:
 681                 return "kernel";
 682         case LTTNG_CONSUMER32_UST:
 683                 return "32-bit user space";
 684         case LTTNG_CONSUMER64_UST:
 685                 return "64-bit user space";
 686         default:
 687                 abort();
 688         }
 689 }
 690
 691 /*
 692  * Init consumer data structures.
 693  */
 694 int lttng_consumer_init(void);
 695
 696 /*
 697  * Set the error socket for communication with a session daemon.
 698  */
 699 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data *ctx,
 700                 int sock);
 701
 702 /*
 703  * Set the command socket path for communication with a session daemon.
 704  */
 705 void lttng_consumer_set_command_sock_path(
 706                 struct lttng_consumer_local_data *ctx, char *sock);
 707
 708 /*
 709  * Send return code to session daemon.
 710  *
 711  * Returns the return code of sendmsg : the number of bytes transmitted or -1
 712  * on error.
 713  */
 714 int lttng_consumer_send_error(struct lttng_consumer_local_data *ctx, int cmd);
 715
 716 /*
 717  * Called from signal handler to ensure a clean exit.
 718  */
 719 void lttng_consumer_should_exit(struct lttng_consumer_local_data *ctx);
 720
 721 /*
 722  * Cleanup the daemon's socket on exit.
 723  */
 724 void lttng_consumer_cleanup(void);
 725
 726 /*
 727  * Poll on the should_quit pipe and the command socket return -1 on error and
 728  * should exit, 0 if data is available on the command socket
 729  */
 730 int lttng_consumer_poll_socket(struct pollfd *kconsumer_sockpoll);
 731
 732 /*
 733  * Copy the fields from the channel that need to be accessed (read-only)
 734  * directly from the stream.
 735  */
 736 void consumer_stream_update_channel_attributes(
 737                 struct lttng_consumer_stream *stream,
 738                 struct lttng_consumer_channel *channel);
 739
 740 struct lttng_consumer_stream *consumer_allocate_stream(uint64_t channel_key,
 741                 uint64_t stream_key,
 742                 const char *channel_name,
 743                 uint64_t relayd_id,
 744                 uint64_t session_id,
 745                 struct lttng_trace_chunk *trace_chunk,
 746                 int cpu,
 747                 int *alloc_ret,
 748                 enum consumer_channel_type type,
 749                 unsigned int monitor);
 750 struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
 751                 uint64_t session_id,
 752                 const uint64_t *chunk_id,
 753                 const char *pathname,
 754                 const char *name,
 755                 uint64_t relayd_id,
 756                 enum lttng_event_output output,
 757                 uint64_t tracefile_size,
 758                 uint64_t tracefile_count,
 759                 uint64_t session_id_per_pid,
 760                 unsigned int monitor,
 761                 unsigned int live_timer_interval,
 762                 const char *root_shm_path,
 763                 const char *shm_path);
 764 void consumer_del_stream(struct lttng_consumer_stream *stream,
 765                 struct lttng_ht *ht);
 766 void consumer_del_metadata_stream(struct lttng_consumer_stream *stream,
 767                 struct lttng_ht *ht);
 768 int consumer_add_channel(struct lttng_consumer_channel *channel,
 769                 struct lttng_consumer_local_data *ctx);
 770 void consumer_del_channel(struct lttng_consumer_channel *channel);
 771
 772 /* lttng-relayd consumer command */
 773 struct consumer_relayd_sock_pair *consumer_find_relayd(uint64_t key);
 774 int consumer_send_relayd_stream(struct lttng_consumer_stream *stream, char *path);
 775 int consumer_send_relayd_streams_sent(uint64_t net_seq_idx);
 776 void close_relayd_stream(struct lttng_consumer_stream *stream);
 777 struct lttng_consumer_channel *consumer_find_channel(uint64_t key);
 778 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream *stream,
 779                 size_t data_size);
 780 void consumer_steal_stream_key(int key, struct lttng_ht *ht);
 781
 782 struct lttng_consumer_local_data *lttng_consumer_create(
 783                 enum lttng_consumer_type type,
 784                 ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream,
 785                         struct lttng_consumer_local_data *ctx),
 786                 int (*recv_channel)(struct lttng_consumer_channel *channel),
 787                 int (*recv_stream)(struct lttng_consumer_stream *stream),
 788                 int (*update_stream)(uint64_t sessiond_key, uint32_t state));
 789 void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx);
 790 ssize_t lttng_consumer_on_read_subbuffer_mmap(
 791                 struct lttng_consumer_local_data *ctx,
 792                 struct lttng_consumer_stream *stream, unsigned long len,
 793                 unsigned long padding,
 794                 struct ctf_packet_index *index);
 795 ssize_t lttng_consumer_on_read_subbuffer_splice(
 796                 struct lttng_consumer_local_data *ctx,
 797                 struct lttng_consumer_stream *stream, unsigned long len,
 798                 unsigned long padding,
 799                 struct ctf_packet_index *index);
 800 int lttng_consumer_sample_snapshot_positions(struct lttng_consumer_stream *stream);
 801 int lttng_consumer_take_snapshot(struct lttng_consumer_stream *stream);
 802 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
 803                 unsigned long *pos);
 804 int lttng_consumer_get_consumed_snapshot(struct lttng_consumer_stream *stream,
 805                 unsigned long *pos);
 806 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream *stream);
 807 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream *stream);
 808 void *consumer_thread_metadata_poll(void *data);
 809 void *consumer_thread_data_poll(void *data);
 810 void *consumer_thread_sessiond_poll(void *data);
 811 void *consumer_thread_channel_poll(void *data);
 812 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx,
 813                 int sock, struct pollfd *consumer_sockpoll);
 814
 815 ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
 816                 struct lttng_consumer_local_data *ctx);
 817 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream);
 818 void consumer_add_relayd_socket(uint64_t net_seq_idx, int sock_type,
 819                 struct lttng_consumer_local_data *ctx, int sock,
 820                 struct pollfd *consumer_sockpoll, struct lttcomm_relayd_sock *relayd_sock,
 821                 uint64_t sessiond_id, uint64_t relayd_session_id);
 822 void consumer_flag_relayd_for_destroy(
 823                 struct consumer_relayd_sock_pair *relayd);
 824 int consumer_data_pending(uint64_t id);
 825 int consumer_send_status_msg(int sock, int ret_code);
 826 int consumer_send_status_channel(int sock,
 827                 struct lttng_consumer_channel *channel);
 828 void notify_thread_del_channel(struct lttng_consumer_local_data *ctx,
 829                 uint64_t key);
 830 void consumer_destroy_relayd(struct consumer_relayd_sock_pair *relayd);
 831 unsigned long consumer_get_consume_start_pos(unsigned long consumed_pos,
 832                 unsigned long produced_pos, uint64_t nb_packets_per_stream,
 833                 uint64_t max_sb_size);
 834 void consumer_add_data_stream(struct lttng_consumer_stream *stream);
 835 void consumer_del_stream_for_data(struct lttng_consumer_stream *stream);
 836 void consumer_add_metadata_stream(struct lttng_consumer_stream *stream);
 837 void consumer_del_stream_for_metadata(struct lttng_consumer_stream *stream);
 838 int consumer_create_index_file(struct lttng_consumer_stream *stream);
 839 int lttng_consumer_rotate_channel(struct lttng_consumer_channel *channel,
 840                 uint64_t key, uint64_t relayd_id, uint32_t metadata,
 841                 struct lttng_consumer_local_data *ctx);
 842 int lttng_consumer_stream_is_rotate_ready(struct lttng_consumer_stream *stream);
 843 int lttng_consumer_rotate_stream(struct lttng_consumer_local_data *ctx,
 844                 struct lttng_consumer_stream *stream);
 845 int lttng_consumer_rotate_ready_streams(struct lttng_consumer_channel *channel,
 846                 uint64_t key, struct lttng_consumer_local_data *ctx);
 847 void lttng_consumer_reset_stream_rotate_state(struct lttng_consumer_stream *stream);
 848 enum lttcomm_return_code lttng_consumer_create_trace_chunk(
 849                 const uint64_t *relayd_id, uint64_t session_id,
 850                 uint64_t chunk_id,
 851                 time_t chunk_creation_timestamp,
 852                 const char *chunk_override_name,
 853                 const struct lttng_credentials *credentials,
 854                 struct lttng_directory_handle *chunk_directory_handle);
 855 enum lttcomm_return_code lttng_consumer_close_trace_chunk(
 856                 const uint64_t *relayd_id, uint64_t session_id,
 857                 uint64_t chunk_id, time_t chunk_close_timestamp,
 858                 const enum lttng_trace_chunk_command_type *close_command);
 859 enum lttcomm_return_code lttng_consumer_trace_chunk_exists(
 860                 const uint64_t *relayd_id, uint64_t session_id,
 861                 uint64_t chunk_id);
 862 void lttng_consumer_cleanup_relayd(struct consumer_relayd_sock_pair *relayd);
 863 enum lttcomm_return_code lttng_consumer_init_command(
 864                 struct lttng_consumer_local_data *ctx,
 865                 const lttng_uuid sessiond_uuid);
 866
 867 #endif /* LIB_CONSUMER_H */