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