src/common/consumer/consumer.h

   1 /*
   2  * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
   3  *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   4  *               2012 - David Goulet <dgoulet@efficios.com>
   5  *               2018 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License, version 2 only,
   9  * as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  14  * more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  19  */
  20
  21 #ifndef LIB_CONSUMER_H
  22 #define LIB_CONSUMER_H
  23
  24 #include <limits.h>
  25 #include <poll.h>
  26 #include <unistd.h>
  27 #include <urcu/list.h>
  28
  29 #include <lttng/lttng.h>
  30
  31 #include <common/hashtable/hashtable.h>
  32 #include <common/compat/fcntl.h>
  33 #include <common/compat/uuid.h>
  34 #include <common/sessiond-comm/sessiond-comm.h>
  35 #include <common/pipe.h>
  36 #include <common/index/ctf-index.h>
  37
  38 /* Commands for consumer */
  39 enum lttng_consumer_command {
  40         LTTNG_CONSUMER_ADD_CHANNEL,
  41         LTTNG_CONSUMER_ADD_STREAM,
  42         /* pause, delete, active depending on fd state */
  43         LTTNG_CONSUMER_UPDATE_STREAM,
  44         /* inform the consumer to quit when all fd has hang up */
  45         LTTNG_CONSUMER_STOP,    /* deprecated */
  46         LTTNG_CONSUMER_ADD_RELAYD_SOCKET,
  47         /* Inform the consumer to kill a specific relayd connection */
  48         LTTNG_CONSUMER_DESTROY_RELAYD,
  49         /* Return to the sessiond if there is data pending for a session */
  50         LTTNG_CONSUMER_DATA_PENDING,
  51         /* Consumer creates a channel and returns it to sessiond. */
  52         LTTNG_CONSUMER_ASK_CHANNEL_CREATION,
  53         LTTNG_CONSUMER_GET_CHANNEL,
  54         LTTNG_CONSUMER_DESTROY_CHANNEL,
  55         LTTNG_CONSUMER_PUSH_METADATA,
  56         LTTNG_CONSUMER_CLOSE_METADATA,
  57         LTTNG_CONSUMER_SETUP_METADATA,
  58         LTTNG_CONSUMER_FLUSH_CHANNEL,
  59         LTTNG_CONSUMER_SNAPSHOT_CHANNEL,
  60         LTTNG_CONSUMER_SNAPSHOT_METADATA,
  61         LTTNG_CONSUMER_STREAMS_SENT,
  62         LTTNG_CONSUMER_DISCARDED_EVENTS,
  63         LTTNG_CONSUMER_LOST_PACKETS,
  64         LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL,
  65         LTTNG_CONSUMER_SET_CHANNEL_MONITOR_PIPE,
  66         LTTNG_CONSUMER_ROTATE_CHANNEL,
  67         LTTNG_CONSUMER_ROTATE_RENAME,
  68         LTTNG_CONSUMER_CHECK_ROTATION_PENDING_LOCAL,
  69         LTTNG_CONSUMER_CHECK_ROTATION_PENDING_RELAY,
  70         LTTNG_CONSUMER_MKDIR,
  71 };
  72
  73 /* State of each fd in consumer */
  74 enum lttng_consumer_stream_state {
  75         LTTNG_CONSUMER_ACTIVE_STREAM,
  76         LTTNG_CONSUMER_PAUSE_STREAM,
  77         LTTNG_CONSUMER_DELETE_STREAM,
  78 };
  79
  80 enum lttng_consumer_type {
  81         LTTNG_CONSUMER_UNKNOWN = 0,
  82         LTTNG_CONSUMER_KERNEL,
  83         LTTNG_CONSUMER64_UST,
  84         LTTNG_CONSUMER32_UST,
  85 };
  86
  87 enum consumer_endpoint_status {
  88         CONSUMER_ENDPOINT_ACTIVE,
  89         CONSUMER_ENDPOINT_INACTIVE,
  90 };
  91
  92 enum consumer_channel_output {
  93         CONSUMER_CHANNEL_MMAP   = 0,
  94         CONSUMER_CHANNEL_SPLICE = 1,
  95 };
  96
  97 enum consumer_channel_type {
  98         CONSUMER_CHANNEL_TYPE_METADATA  = 0,
  99         CONSUMER_CHANNEL_TYPE_DATA      = 1,
 100 };
 101
 102 extern struct lttng_consumer_global_data consumer_data;
 103
 104 struct stream_list {
 105         struct cds_list_head head;
 106         unsigned int count;
 107 };
 108
 109 /* Stub. */
 110 struct consumer_metadata_cache;
 111
 112 struct lttng_consumer_channel {
 113         /* HT node used for consumer_data.channel_ht */
 114         struct lttng_ht_node_u64 node;
 115         /* Indexed key. Incremented value in the consumer. */
 116         uint64_t key;
 117         /* Number of streams referencing this channel */
 118         int refcount;
 119         /* Tracing session id on the session daemon side. */
 120         uint64_t session_id;
 121         /*
 122          * Session id when requesting metadata to the session daemon for
 123          * a session with per-PID buffers.
 124          */
 125         uint64_t session_id_per_pid;
 126         /* Channel trace file path name. */
 127         char pathname[PATH_MAX];
 128         /* Channel name. */
 129         char name[LTTNG_SYMBOL_NAME_LEN];
 130         /* UID and GID of the session owning this channel. */
 131         uid_t uid;
 132         gid_t gid;
 133         /* Relayd id of the channel. -1ULL if it does not apply. */
 134         uint64_t relayd_id;
 135         /*
 136          * Number of streams NOT initialized yet. This is used in order to not
 137          * delete this channel if streams are getting initialized.
 138          */
 139         unsigned int nb_init_stream_left;
 140         /* Output type (mmap or splice). */
 141         enum consumer_channel_output output;
 142         /* Channel type for stream */
 143         enum consumer_channel_type type;
 144
 145         /* For UST */
 146         uid_t ust_app_uid;      /* Application UID. */
 147         struct ustctl_consumer_channel *uchan;
 148         unsigned char uuid[UUID_STR_LEN];
 149         /*
 150          * Temporary stream list used to store the streams once created and waiting
 151          * to be sent to the session daemon by receiving the
 152          * LTTNG_CONSUMER_GET_CHANNEL.
 153          */
 154         struct stream_list streams;
 155
 156         /*
 157          * Set if the channel is metadata. We keep a reference to the stream
 158          * because we have to flush data once pushed by the session daemon. For a
 159          * regular channel, this is always set to NULL.
 160          */
 161         struct lttng_consumer_stream *metadata_stream;
 162
 163         /* for UST */
 164         int wait_fd;
 165         /* Node within channel thread ht */
 166         struct lttng_ht_node_u64 wait_fd_node;
 167
 168         /* Metadata cache is metadata channel */
 169         struct consumer_metadata_cache *metadata_cache;
 170
 171         /* For UST metadata periodical flush */
 172         int switch_timer_enabled;
 173         timer_t switch_timer;
 174         int switch_timer_error;
 175
 176         /* For the live mode */
 177         int live_timer_enabled;
 178         timer_t live_timer;
 179         int live_timer_error;
 180
 181         /* For channel monitoring timer. */
 182         int monitor_timer_enabled;
 183         timer_t monitor_timer;
 184
 185         /* On-disk circular buffer */
 186         uint64_t tracefile_size;
 187         uint64_t tracefile_count;
 188         /*
 189          * Monitor or not the streams of this channel meaning this indicates if the
 190          * streams should be sent to the data/metadata thread or added to the no
 191          * monitor list of the channel.
 192          */
 193         unsigned int monitor;
 194
 195         /*
 196          * Channel lock.
 197          *
 198          * This lock protects against concurrent update of channel.
 199          *
 200          * This is nested INSIDE the consumer data lock.
 201          * This is nested OUTSIDE the channel timer lock.
 202          * This is nested OUTSIDE the metadata cache lock.
 203          * This is nested OUTSIDE stream lock.
 204          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 205          */
 206         pthread_mutex_t lock;
 207
 208         /*
 209          * Channel teardown lock.
 210          *
 211          * This lock protect against teardown of channel. It is _never_
 212          * taken by the timer handler.
 213          *
 214          * This is nested INSIDE the consumer data lock.
 215          * This is nested INSIDE the channel 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 timer_lock;
 221
 222         /* Timer value in usec for live streaming. */
 223         unsigned int live_timer_interval;
 224
 225         int *stream_fds;
 226         int nr_stream_fds;
 227         char root_shm_path[PATH_MAX];
 228         char shm_path[PATH_MAX];
 229         /* Total number of discarded events for that channel. */
 230         uint64_t discarded_events;
 231         /* Total number of missed packets due to overwriting (overwrite). */
 232         uint64_t lost_packets;
 233
 234         bool streams_sent_to_relayd;
 235
 236         /*
 237          * Account how many streams are waiting for their rotation to be
 238          * complete. When this number reaches 0, we inform the session
 239          * daemon that this channel has finished its rotation.
 240          */
 241         uint64_t nr_stream_rotate_pending;
 242
 243         /*
 244          * The chunk id where we currently write the data. This value is sent
 245          * to the relay when we add a stream and when a stream rotates. This
 246          * allows to keep track of where each stream on the relay is writing.
 247          */
 248         uint64_t current_chunk_id;
 249 };
 250
 251 /*
 252  * Internal representation of the streams, sessiond_key is used to identify
 253  * uniquely a stream.
 254  */
 255 struct lttng_consumer_stream {
 256         /* HT node used by the data_ht and metadata_ht */
 257         struct lttng_ht_node_u64 node;
 258         /* stream indexed per channel key node */
 259         struct lttng_ht_node_u64 node_channel_id;
 260         /* HT node used in consumer_data.stream_list_ht */
 261         struct lttng_ht_node_u64 node_session_id;
 262         /* Pointer to associated channel. */
 263         struct lttng_consumer_channel *chan;
 264
 265         /* Key by which the stream is indexed for 'node'. */
 266         uint64_t key;
 267         /*
 268          * File descriptor of the data output file. This can be either a file or a
 269          * socket fd for relayd streaming.
 270          */
 271         int out_fd; /* output file to write the data */
 272         /* Write position in the output file descriptor */
 273         off_t out_fd_offset;
 274         /* Amount of bytes written to the output */
 275         uint64_t output_written;
 276         enum lttng_consumer_stream_state state;
 277         int shm_fd_is_copy;
 278         int data_read;
 279         int hangup_flush_done;
 280
 281         /*
 282          * Whether the stream is in a "complete" state (e.g. it does not have a
 283          * partially written sub-buffer.
 284          *
 285          * Initialized to "false" on stream creation (first packet is empty).
 286          *
 287          * The various transitions of the quiescent state are:
 288          *     - On "start" tracing: set to false, since the stream is not
 289          *       "complete".
 290          *     - On "stop" tracing: if !quiescent -> flush FINAL (update
 291          *       timestamp_end), and set to true; the stream has entered a
 292          *       complete/quiescent state.
 293          *     - On "destroy" or stream/application hang-up: if !quiescent ->
 294          *       flush FINAL, and set to true.
 295          *
 296          * NOTE: Update and read are protected by the stream lock.
 297          */
 298         bool quiescent;
 299
 300         /*
 301          * metadata_timer_lock protects flags waiting_on_metadata and
 302          * missed_metadata_flush.
 303          */
 304         pthread_mutex_t metadata_timer_lock;
 305         /*
 306          * Flag set when awaiting metadata to be pushed. Used in the
 307          * timer thread to skip waiting on the stream (and stream lock) to
 308          * ensure we can proceed to flushing metadata in live mode.
 309          */
 310         bool waiting_on_metadata;
 311         /* Raised when a timer misses a metadata flush. */
 312         bool missed_metadata_flush;
 313
 314         enum lttng_event_output output;
 315         /* Maximum subbuffer size. */
 316         unsigned long max_sb_size;
 317
 318         /*
 319          * Still used by the kernel for MMAP output. For UST, the ustctl getter is
 320          * used for the mmap base and offset.
 321          */
 322         void *mmap_base;
 323         unsigned long mmap_len;
 324
 325         /* For UST */
 326
 327         int wait_fd;
 328         /* UID/GID of the user owning the session to which stream belongs */
 329         uid_t uid;
 330         gid_t gid;
 331         /* Network sequence number. Indicating on which relayd socket it goes. */
 332         uint64_t net_seq_idx;
 333         /*
 334          * Indicate if this stream was successfully sent to a relayd. This is set
 335          * after the refcount of the relayd is incremented and is checked when the
 336          * stream is closed before decrementing the refcount in order to avoid an
 337          * unbalanced state.
 338          */
 339         unsigned int sent_to_relayd;
 340
 341         /* Identify if the stream is the metadata */
 342         unsigned int metadata_flag;
 343         /*
 344          * Last known metadata version, reset the metadata file in case
 345          * of change.
 346          */
 347         uint64_t metadata_version;
 348         /* Used when the stream is set for network streaming */
 349         uint64_t relayd_stream_id;
 350         /*
 351          * When sending a stream packet to a relayd, this number is used to track
 352          * the packet sent by the consumer and seen by the relayd. When sending the
 353          * data header to the relayd, this number is sent and if the transmission
 354          * was successful, it is incremented.
 355          *
 356          * Even if the full data is not fully transmitted it won't matter since
 357          * only two possible error can happen after that where either the relayd
 358          * died or a read error is detected on the stream making this value useless
 359          * after that.
 360          *
 361          * This value SHOULD be read/updated atomically or with the lock acquired.
 362          */
 363         uint64_t next_net_seq_num;
 364         /*
 365          * Lock to use the stream FDs since they are used between threads.
 366          *
 367          * This is nested INSIDE the consumer_data lock.
 368          * This is nested INSIDE the channel lock.
 369          * This is nested INSIDE the channel timer lock.
 370          * This is nested OUTSIDE the metadata cache lock.
 371          * This is nested OUTSIDE consumer_relayd_sock_pair lock.
 372          */
 373         pthread_mutex_t lock;
 374         /* Tracing session id */
 375         uint64_t session_id;
 376         /*
 377          * Indicates if the stream end point is still active or not (network
 378          * streaming or local file system). The thread "owning" the stream is
 379          * handling this status and can be notified of a state change through the
 380          * consumer data appropriate pipe.
 381          */
 382         enum consumer_endpoint_status endpoint_status;
 383         /* Stream name. Format is: <channel_name>_<cpu_number> */
 384         char name[LTTNG_SYMBOL_NAME_LEN];
 385         /* Internal state of libustctl. */
 386         struct ustctl_consumer_stream *ustream;
 387         struct cds_list_head send_node;
 388         /* On-disk circular buffer */
 389         uint64_t tracefile_size_current;
 390         uint64_t tracefile_count_current;
 391         /*
 392          * Monitor or not the streams of this channel meaning this indicates if the
 393          * streams should be sent to the data/metadata thread or added to the no
 394          * monitor list of the channel.
 395          */
 396         unsigned int monitor;
 397         /*
 398          * Indicate if the stream is globally visible meaning that it has been
 399          * added to the multiple hash tables. If *not* set, NO lock should be
 400          * acquired in the destroy path.
 401          */
 402         unsigned int globally_visible;
 403         /*
 404          * Pipe to wake up the metadata poll thread when the UST metadata
 405          * cache is updated.
 406          */
 407         int ust_metadata_poll_pipe[2];
 408         /*
 409          * How much metadata was read from the metadata cache and sent
 410          * to the channel.
 411          */
 412         uint64_t ust_metadata_pushed;
 413         /*
 414          * Copy of the last discarded event value to detect the overflow of
 415          * the counter.
 416          */
 417         uint64_t last_discarded_events;
 418         /* Copy of the sequence number of the last packet extracted. */
 419         uint64_t last_sequence_number;
 420         /*
 421          * A stream is created with a trace_archive_id matching the session's
 422          * current trace archive id at the time of the creation of the stream.
 423          * It is incremented when the rotate_position is reached.
 424          */
 425         uint64_t trace_archive_id;
 426         /*
 427          * Index file object of the index file for this stream.
 428          */
 429         struct lttng_index_file *index_file;
 430
 431         /*
 432          * Local pipe to extract data when using splice.
 433          */
 434         int splice_pipe[2];
 435
 436         /*
 437          * Rendez-vous point between data and metadata stream in live mode.
 438          */
 439         pthread_cond_t metadata_rdv;
 440         pthread_mutex_t metadata_rdv_lock;
 441
 442         /*
 443          * rotate_position represents the position in the ring-buffer that has to
 444          * be flushed to disk to complete the ongoing rotation. When that position
 445          * is reached, this tracefile can be closed and a new one is created in
 446          * channel_read_only_attributes.path.
 447          */
 448         unsigned long rotate_position;
 449
 450         /*
 451          * Read-only copies of channel values. We cannot safely access the
 452          * channel from a stream, so we need to have a local copy of these
 453          * fields in the stream object. These fields should be removed from
 454          * the stream objects when we introduce refcounting.
 455          */
 456         struct {
 457                 char path[LTTNG_PATH_MAX];
 458                 uint64_t tracefile_size;
 459         } channel_read_only_attributes;
 460
 461         /*
 462          * Flag to inform the data or metadata thread that a stream is
 463          * ready to be rotated.
 464          */
 465         bool rotate_ready;
 466
 467         /* Indicate if the stream still has some data to be read. */
 468         unsigned int has_data:1;
 469         /*
 470          * Inform the consumer or relay to reset the metadata
 471          * file before writing in it (regeneration).
 472          */
 473         unsigned int reset_metadata_flag:1;
 474 };
 475
 476 /*
 477  * Internal representation of a relayd socket pair.
 478  */
 479 struct consumer_relayd_sock_pair {
 480         /* Network sequence number. */
 481         uint64_t net_seq_idx;
 482         /* Number of stream associated with this relayd */
 483         int refcount;
 484
 485         /*
 486          * This flag indicates whether or not we should destroy this object. The
 487          * destruction should ONLY occurs when this flag is set and the refcount is
 488          * set to zero.
 489          */
 490         unsigned int destroy_flag;
 491
 492         /*
 493          * Mutex protecting the control socket to avoid out of order packets
 494          * between threads sending data to the relayd. Since metadata data is sent
 495          * over that socket, at least two sendmsg() are needed (header + data)
 496          * creating a race for packets to overlap between threads using it.
 497          *
 498          * This is nested INSIDE the consumer_data lock.
 499          * This is nested INSIDE the stream lock.
 500          */
 501         pthread_mutex_t ctrl_sock_mutex;
 502
 503         /* Control socket. Command and metadata are passed over it */
 504         struct lttcomm_relayd_sock control_sock;
 505
 506         /*
 507          * We don't need a mutex at this point since we only splice or write single
 508          * large chunk of data with a header appended at the begining. Moreover,
 509          * this socket is for now only used in a single thread.
 510          */
 511         struct lttcomm_relayd_sock data_sock;
 512         struct lttng_ht_node_u64 node;
 513
 514         /* Session id on both sides for the sockets. */
 515         uint64_t relayd_session_id;
 516         uint64_t sessiond_session_id;
 517         struct lttng_consumer_local_data *ctx;
 518 };
 519
 520 /*
 521  * UST consumer local data to the program. One or more instance per
 522  * process.
 523  */
 524 struct lttng_consumer_local_data {
 525         /*
 526          * Function to call when data is available on a buffer.
 527          * Returns the number of bytes read, or negative error value.
 528          */
 529         ssize_t (*on_buffer_ready)(struct lttng_consumer_stream *stream,
 530                         struct lttng_consumer_local_data *ctx);
 531         /*
 532          * function to call when we receive a new channel, it receives a
 533          * newly allocated channel, depending on the return code of this
 534          * function, the new channel will be handled by the application
 535          * or the library.
 536          *
 537          * Returns:
 538          *    > 0 (success, FD is kept by application)
 539          *   == 0 (success, FD is left to library)
 540          *    < 0 (error)
 541          */
 542         int (*on_recv_channel)(struct lttng_consumer_channel *channel);
 543         /*
 544          * function to call when we receive a new stream, it receives a
 545          * newly allocated stream, depending on the return code of this
 546          * function, the new stream will be handled by the application
 547          * or the library.
 548          *
 549          * Returns:
 550          *    > 0 (success, FD is kept by application)
 551          *   == 0 (success, FD is left to library)
 552          *    < 0 (error)
 553          */
 554         int (*on_recv_stream)(struct lttng_consumer_stream *stream);
 555         /*
 556          * function to call when a stream is getting updated by the session
 557          * daemon, this function receives the sessiond key and the new
 558          * state, depending on the return code of this function the
 559          * update of state for the stream is handled by the application
 560          * or the library.
 561          *
 562          * Returns:
 563          *    > 0 (success, FD is kept by application)
 564          *   == 0 (success, FD is left to library)
 565          *    < 0 (error)
 566          */
 567         int (*on_update_stream)(uint64_t sessiond_key, uint32_t state);
 568         enum lttng_consumer_type type;
 569         /* socket to communicate errors with sessiond */
 570         int consumer_error_socket;
 571         /* socket to ask metadata to sessiond. */
 572         int consumer_metadata_socket;
 573         /*
 574          * Protect consumer_metadata_socket.
 575          *
 576          * This is nested OUTSIDE the metadata cache lock.
 577          */
 578         pthread_mutex_t metadata_socket_lock;
 579         /* socket to exchange commands with sessiond */
 580         char *consumer_command_sock_path;
 581         /* communication with splice */
 582         int consumer_channel_pipe[2];
 583         /* Data stream poll thread pipe. To transfer data stream to the thread */
 584         struct lttng_pipe *consumer_data_pipe;
 585
 586         /*
 587          * Data thread use that pipe to catch wakeup from read subbuffer that
 588          * detects that there is still data to be read for the stream encountered.
 589          * Before doing so, the stream is flagged to indicate that there is still
 590          * data to be read.
 591          *
 592          * Both pipes (read/write) are owned and used inside the data thread.
 593          */
 594         struct lttng_pipe *consumer_wakeup_pipe;
 595         /* Indicate if the wakeup thread has been notified. */
 596         unsigned int has_wakeup:1;
 597
 598         /* to let the signal handler wake up the fd receiver thread */
 599         int consumer_should_quit[2];
 600         /* Metadata poll thread pipe. Transfer metadata stream to it */
 601         struct lttng_pipe *consumer_metadata_pipe;
 602         /*
 603          * Pipe used by the channel monitoring timers to provide state samples
 604          * to the session daemon (write-only).
 605          */
 606         int channel_monitor_pipe;
 607 };
 608
 609 /*
 610  * Library-level data. One instance per process.
 611  */
 612 struct lttng_consumer_global_data {
 613         /*
 614          * At this time, this lock is used to ensure coherence between the count
 615          * and number of element in the hash table. It's also a protection for
 616          * concurrent read/write between threads.
 617          *
 618          * This is nested OUTSIDE the stream lock.
 619          * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
 620          */
 621         pthread_mutex_t lock;
 622
 623         /*
 624          * Number of streams in the data stream hash table declared outside.
 625          * Protected by consumer_data.lock.
 626          */
 627         int stream_count;
 628
 629         /* Channel hash table protected by consumer_data.lock. */
 630         struct lttng_ht *channel_ht;
 631         /*
 632          * Flag specifying if the local array of FDs needs update in the
 633          * poll function. Protected by consumer_data.lock.
 634          */
 635         unsigned int need_update;
 636         enum lttng_consumer_type type;
 637
 638         /*
 639          * Relayd socket(s) hashtable indexed by network sequence number. Each
 640          * stream has an index which associate the right relayd socket to use.
 641          */
 642         struct lttng_ht *relayd_ht;
 643
 644         /*
 645          * This hash table contains all streams (metadata and data) indexed by
 646          * session id. In other words, the ht is indexed by session id and each
 647          * bucket contains the list of associated streams.
 648          *
 649          * This HT uses the "node_session_id" of the consumer stream.
 650          */
 651         struct lttng_ht *stream_list_ht;
 652
 653         /*
 654          * This HT uses the "node_channel_id" of the consumer stream.
 655          */
 656         struct lttng_ht *stream_per_chan_id_ht;
 657 };
 658
 659 /*
 660  * Set to nonzero when the consumer is exiting. Updated by signal
 661  * handler and thread exit, read by threads.
 662  */
 663 extern int consumer_quit;
 664
 665 /*
 666  * Set to nonzero when the consumer is exiting. Updated by signal
 667  * handler and thread exit, read by threads.
 668  */
 669 extern int consumer_quit;
 670
 671 /* Flag used to temporarily pause data consumption from testpoints. */
 672 extern int data_consumption_paused;
 673
 674 /* Return a human-readable consumer type string that is suitable for logging. */
 675 static inline
 676 const char *lttng_consumer_type_str(enum lttng_consumer_type type)
 677 {
 678         switch (type) {
 679         case LTTNG_CONSUMER_UNKNOWN:
 680                 return "unknown";
 681         case LTTNG_CONSUMER_KERNEL:
 682                 return "kernel";
 683         case LTTNG_CONSUMER32_UST:
 684                 return "32-bit user space";
 685         case LTTNG_CONSUMER64_UST:
 686                 return "64-bit user space";
 687         default:
 688                 abort();
 689         }
 690 }
 691
 692 /*
 693  * Init consumer data structures.
 694  */
 695 int lttng_consumer_init(void);
 696
 697 /*
 698  * Set the error socket for communication with a session daemon.
 699  */
 700 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data *ctx,
 701                 int sock);
 702
 703 /*
 704  * Set the command socket path for communication with a session daemon.
 705  */
 706 void lttng_consumer_set_command_sock_path(
 707                 struct lttng_consumer_local_data *ctx, char *sock);
 708
 709 /*
 710  * Send return code to session daemon.
 711  *
 712  * Returns the return code of sendmsg : the number of bytes transmitted or -1
 713  * on error.
 714  */
 715 int lttng_consumer_send_error(struct lttng_consumer_local_data *ctx, int cmd);
 716
 717 /*
 718  * Called from signal handler to ensure a clean exit.
 719  */
 720 void lttng_consumer_should_exit(struct lttng_consumer_local_data *ctx);
 721
 722 /*
 723  * Cleanup the daemon's socket on exit.
 724  */
 725 void lttng_consumer_cleanup(void);
 726
 727 /*
 728  * Poll on the should_quit pipe and the command socket return -1 on error and
 729  * should exit, 0 if data is available on the command socket
 730  */
 731 int lttng_consumer_poll_socket(struct pollfd *kconsumer_sockpoll);
 732
 733 /*
 734  * Copy the fields from the channel that need to be accessed (read-only)
 735  * directly from the stream.
 736  */
 737 void consumer_stream_update_channel_attributes(
 738                 struct lttng_consumer_stream *stream,
 739                 struct lttng_consumer_channel *channel);
 740
 741 struct lttng_consumer_stream *consumer_allocate_stream(uint64_t channel_key,
 742                 uint64_t stream_key,
 743                 enum lttng_consumer_stream_state state,
 744                 const char *channel_name,
 745                 uid_t uid,
 746                 gid_t gid,
 747                 uint64_t relayd_id,
 748                 uint64_t session_id,
 749                 int cpu,
 750                 int *alloc_ret,
 751                 enum consumer_channel_type type,
 752                 unsigned int monitor,
 753                 uint64_t trace_archive_id);
 754 struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
 755                 uint64_t session_id,
 756                 const char *pathname,
 757                 const char *name,
 758                 uid_t uid,
 759                 gid_t gid,
 760                 uint64_t relayd_id,
 761                 enum lttng_event_output output,
 762                 uint64_t tracefile_size,
 763                 uint64_t tracefile_count,
 764                 uint64_t session_id_per_pid,
 765                 unsigned int monitor,
 766                 unsigned int live_timer_interval,
 767                 const char *root_shm_path,
 768                 const char *shm_path);
 769 void consumer_del_stream(struct lttng_consumer_stream *stream,
 770                 struct lttng_ht *ht);
 771 void consumer_del_metadata_stream(struct lttng_consumer_stream *stream,
 772                 struct lttng_ht *ht);
 773 int consumer_add_channel(struct lttng_consumer_channel *channel,
 774                 struct lttng_consumer_local_data *ctx);
 775 void consumer_del_channel(struct lttng_consumer_channel *channel);
 776
 777 /* lttng-relayd consumer command */
 778 struct consumer_relayd_sock_pair *consumer_find_relayd(uint64_t key);
 779 int consumer_send_relayd_stream(struct lttng_consumer_stream *stream, char *path);
 780 int consumer_send_relayd_streams_sent(uint64_t net_seq_idx);
 781 void close_relayd_stream(struct lttng_consumer_stream *stream);
 782 struct lttng_consumer_channel *consumer_find_channel(uint64_t key);
 783 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream *stream,
 784                 size_t data_size);
 785 void consumer_steal_stream_key(int key, struct lttng_ht *ht);
 786
 787 struct lttng_consumer_local_data *lttng_consumer_create(
 788                 enum lttng_consumer_type type,
 789                 ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream,
 790                         struct lttng_consumer_local_data *ctx),
 791                 int (*recv_channel)(struct lttng_consumer_channel *channel),
 792                 int (*recv_stream)(struct lttng_consumer_stream *stream),
 793                 int (*update_stream)(uint64_t sessiond_key, uint32_t state));
 794 void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx);
 795 ssize_t lttng_consumer_on_read_subbuffer_mmap(
 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 ssize_t lttng_consumer_on_read_subbuffer_splice(
 801                 struct lttng_consumer_local_data *ctx,
 802                 struct lttng_consumer_stream *stream, unsigned long len,
 803                 unsigned long padding,
 804                 struct ctf_packet_index *index);
 805 int lttng_consumer_sample_snapshot_positions(struct lttng_consumer_stream *stream);
 806 int lttng_consumer_take_snapshot(struct lttng_consumer_stream *stream);
 807 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream *stream,
 808                 unsigned long *pos);
 809 int lttng_consumer_get_consumed_snapshot(struct lttng_consumer_stream *stream,
 810                 unsigned long *pos);
 811 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream *stream);
 812 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream *stream);
 813 void *consumer_thread_metadata_poll(void *data);
 814 void *consumer_thread_data_poll(void *data);
 815 void *consumer_thread_sessiond_poll(void *data);
 816 void *consumer_thread_channel_poll(void *data);
 817 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx,
 818                 int sock, struct pollfd *consumer_sockpoll);
 819
 820 ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
 821                 struct lttng_consumer_local_data *ctx);
 822 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream);
 823 void consumer_add_relayd_socket(uint64_t net_seq_idx, int sock_type,
 824                 struct lttng_consumer_local_data *ctx, int sock,
 825                 struct pollfd *consumer_sockpoll, struct lttcomm_relayd_sock *relayd_sock,
 826                 uint64_t sessiond_id, uint64_t relayd_session_id);
 827 void consumer_flag_relayd_for_destroy(
 828                 struct consumer_relayd_sock_pair *relayd);
 829 int consumer_data_pending(uint64_t id);
 830 int consumer_send_status_msg(int sock, int ret_code);
 831 int consumer_send_status_channel(int sock,
 832                 struct lttng_consumer_channel *channel);
 833 void notify_thread_del_channel(struct lttng_consumer_local_data *ctx,
 834                 uint64_t key);
 835 void consumer_destroy_relayd(struct consumer_relayd_sock_pair *relayd);
 836 unsigned long consumer_get_consume_start_pos(unsigned long consumed_pos,
 837                 unsigned long produced_pos, uint64_t nb_packets_per_stream,
 838                 uint64_t max_sb_size);
 839 void consumer_add_data_stream(struct lttng_consumer_stream *stream);
 840 void consumer_del_stream_for_data(struct lttng_consumer_stream *stream);
 841 void consumer_add_metadata_stream(struct lttng_consumer_stream *stream);
 842 void consumer_del_stream_for_metadata(struct lttng_consumer_stream *stream);
 843 int consumer_create_index_file(struct lttng_consumer_stream *stream);
 844 int lttng_consumer_rotate_channel(uint64_t key, const char *path,
 845                 uint64_t relayd_id, uint32_t metadata,
 846                 uint64_t new_chunk_id, struct lttng_consumer_local_data *ctx);
 847 int lttng_consumer_stream_is_rotate_ready(struct lttng_consumer_stream *stream);
 848 int lttng_consumer_rotate_stream(struct lttng_consumer_local_data *ctx,
 849                 struct lttng_consumer_stream *stream, bool *rotated);
 850 int lttng_consumer_rotate_ready_streams(uint64_t key,
 851                 struct lttng_consumer_local_data *ctx);
 852 int lttng_consumer_rotate_rename(const char *current_path, const char *new_path,
 853                 uid_t uid, gid_t gid, uint64_t relayd_id);
 854 int lttng_consumer_check_rotation_pending_local(uint64_t session_id,
 855                 uint64_t chunk_id);
 856 int lttng_consumer_check_rotation_pending_relay(uint64_t session_id,
 857                 uint64_t relayd_id, uint64_t chunk_id);
 858 void lttng_consumer_reset_stream_rotate_state(struct lttng_consumer_stream *stream);
 859 int lttng_consumer_mkdir(const char *path, uid_t uid, gid_t gid,
 860                 uint64_t relayd_id);
 861 void lttng_consumer_cleanup_relayd(struct consumer_relayd_sock_pair *relayd);
 862
 863 #endif /* LIB_CONSUMER_H */