2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * 2012 - David Goulet <dgoulet@efficios.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License, version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20 #ifndef LIB_CONSUMER_H
21 #define LIB_CONSUMER_H
26 #include <urcu/list.h>
28 #include <lttng/lttng.h>
30 #include <common/hashtable/hashtable.h>
31 #include <common/compat/fcntl.h>
32 #include <common/compat/uuid.h>
33 #include <common/sessiond-comm/sessiond-comm.h>
34 #include <common/pipe.h>
35 #include <common/index/ctf-index.h>
37 /* Commands for consumer */
38 enum lttng_consumer_command
{
39 LTTNG_CONSUMER_ADD_CHANNEL
,
40 LTTNG_CONSUMER_ADD_STREAM
,
41 /* pause, delete, active depending on fd state */
42 LTTNG_CONSUMER_UPDATE_STREAM
,
43 /* inform the consumer to quit when all fd has hang up */
44 LTTNG_CONSUMER_STOP
, /* deprecated */
45 LTTNG_CONSUMER_ADD_RELAYD_SOCKET
,
46 /* Inform the consumer to kill a specific relayd connection */
47 LTTNG_CONSUMER_DESTROY_RELAYD
,
48 /* Return to the sessiond if there is data pending for a session */
49 LTTNG_CONSUMER_DATA_PENDING
,
50 /* Consumer creates a channel and returns it to sessiond. */
51 LTTNG_CONSUMER_ASK_CHANNEL_CREATION
,
52 LTTNG_CONSUMER_GET_CHANNEL
,
53 LTTNG_CONSUMER_DESTROY_CHANNEL
,
54 LTTNG_CONSUMER_PUSH_METADATA
,
55 LTTNG_CONSUMER_CLOSE_METADATA
,
56 LTTNG_CONSUMER_SETUP_METADATA
,
57 LTTNG_CONSUMER_FLUSH_CHANNEL
,
58 LTTNG_CONSUMER_SNAPSHOT_CHANNEL
,
59 LTTNG_CONSUMER_SNAPSHOT_METADATA
,
60 LTTNG_CONSUMER_STREAMS_SENT
,
61 LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL
,
64 /* State of each fd in consumer */
65 enum lttng_consumer_stream_state
{
66 LTTNG_CONSUMER_ACTIVE_STREAM
,
67 LTTNG_CONSUMER_PAUSE_STREAM
,
68 LTTNG_CONSUMER_DELETE_STREAM
,
71 enum lttng_consumer_type
{
72 LTTNG_CONSUMER_UNKNOWN
= 0,
73 LTTNG_CONSUMER_KERNEL
,
78 enum consumer_endpoint_status
{
79 CONSUMER_ENDPOINT_ACTIVE
,
80 CONSUMER_ENDPOINT_INACTIVE
,
83 enum consumer_channel_output
{
84 CONSUMER_CHANNEL_MMAP
= 0,
85 CONSUMER_CHANNEL_SPLICE
= 1,
88 enum consumer_channel_type
{
89 CONSUMER_CHANNEL_TYPE_METADATA
= 0,
90 CONSUMER_CHANNEL_TYPE_DATA
= 1,
93 extern struct lttng_consumer_global_data consumer_data
;
96 struct cds_list_head head
;
101 struct consumer_metadata_cache
;
103 struct lttng_consumer_channel
{
104 /* HT node used for consumer_data.channel_ht */
105 struct lttng_ht_node_u64 node
;
106 /* Indexed key. Incremented value in the consumer. */
108 /* Number of streams referencing this channel */
110 /* Tracing session id on the session daemon side. */
113 * Session id when requesting metadata to the session daemon for
114 * a session with per-PID buffers.
116 uint64_t session_id_per_pid
;
117 /* Channel trace file path name. */
118 char pathname
[PATH_MAX
];
120 char name
[LTTNG_SYMBOL_NAME_LEN
];
121 /* UID and GID of the session owning this channel. */
124 /* Relayd id of the channel. -1ULL if it does not apply. */
127 * Number of streams NOT initialized yet. This is used in order to not
128 * delete this channel if streams are getting initialized.
130 unsigned int nb_init_stream_left
;
131 /* Output type (mmap or splice). */
132 enum consumer_channel_output output
;
133 /* Channel type for stream */
134 enum consumer_channel_type type
;
137 uid_t ust_app_uid
; /* Application UID. */
138 struct ustctl_consumer_channel
*uchan
;
139 unsigned char uuid
[UUID_STR_LEN
];
141 * Temporary stream list used to store the streams once created and waiting
142 * to be sent to the session daemon by receiving the
143 * LTTNG_CONSUMER_GET_CHANNEL.
145 struct stream_list streams
;
148 * Set if the channel is metadata. We keep a reference to the stream
149 * because we have to flush data once pushed by the session daemon. For a
150 * regular channel, this is always set to NULL.
152 struct lttng_consumer_stream
*metadata_stream
;
156 /* Node within channel thread ht */
157 struct lttng_ht_node_u64 wait_fd_node
;
159 /* Metadata cache is metadata channel */
160 struct consumer_metadata_cache
*metadata_cache
;
161 /* For UST metadata periodical flush */
162 int switch_timer_enabled
;
163 timer_t switch_timer
;
164 int switch_timer_error
;
166 /* For the live mode */
167 int live_timer_enabled
;
169 int live_timer_error
;
171 /* On-disk circular buffer */
172 uint64_t tracefile_size
;
173 uint64_t tracefile_count
;
175 * Monitor or not the streams of this channel meaning this indicates if the
176 * streams should be sent to the data/metadata thread or added to the no
177 * monitor list of the channel.
179 unsigned int monitor
;
184 * This lock protects against concurrent update of channel.
186 * This is nested INSIDE the consumer data lock.
187 * This is nested OUTSIDE the channel timer lock.
188 * This is nested OUTSIDE the metadata cache lock.
189 * This is nested OUTSIDE stream lock.
190 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
192 pthread_mutex_t lock
;
195 * Channel teardown lock.
197 * This lock protect against teardown of channel. It is _never_
198 * taken by the timer handler.
200 * This is nested INSIDE the consumer data lock.
201 * This is nested INSIDE the channel 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.
206 pthread_mutex_t timer_lock
;
208 /* Timer value in usec for live streaming. */
209 unsigned int live_timer_interval
;
213 char root_shm_path
[PATH_MAX
];
214 char shm_path
[PATH_MAX
];
218 * Internal representation of the streams, sessiond_key is used to identify
221 struct lttng_consumer_stream
{
222 /* HT node used by the data_ht and metadata_ht */
223 struct lttng_ht_node_u64 node
;
224 /* stream indexed per channel key node */
225 struct lttng_ht_node_u64 node_channel_id
;
226 /* HT node used in consumer_data.stream_list_ht */
227 struct lttng_ht_node_u64 node_session_id
;
228 /* Pointer to associated channel. */
229 struct lttng_consumer_channel
*chan
;
231 /* Key by which the stream is indexed for 'node'. */
234 * File descriptor of the data output file. This can be either a file or a
235 * socket fd for relayd streaming.
237 int out_fd
; /* output file to write the data */
238 /* Write position in the output file descriptor */
240 /* Amount of bytes written to the output */
241 uint64_t output_written
;
242 enum lttng_consumer_stream_state state
;
245 int hangup_flush_done
;
248 * Whether the stream is in a "complete" state (e.g. it does not have a
249 * partially written sub-buffer.
251 * Initialized to "false" on stream creation (first packet is empty).
253 * The various transitions of the quiescent state are:
254 * - On "start" tracing: set to false, since the stream is not
256 * - On "stop" tracing: if !quiescent -> flush FINAL (update
257 * timestamp_end), and set to true; the stream has entered a
258 * complete/quiescent state.
259 * - On "destroy" or stream/application hang-up: if !quiescent ->
260 * flush FINAL, and set to true.
262 * NOTE: Update and read are protected by the stream lock.
267 * metadata_timer_lock protects flags waiting_on_metadata and
268 * missed_metadata_flush.
270 pthread_mutex_t metadata_timer_lock
;
272 * Flag set when awaiting metadata to be pushed. Used in the
273 * timer thread to skip waiting on the stream (and stream lock) to
274 * ensure we can proceed to flushing metadata in live mode.
276 bool waiting_on_metadata
;
277 /* Raised when a timer misses a metadata flush. */
278 bool missed_metadata_flush
;
280 enum lttng_event_output output
;
281 /* Maximum subbuffer size. */
282 unsigned long max_sb_size
;
285 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
286 * used for the mmap base and offset.
289 unsigned long mmap_len
;
294 /* UID/GID of the user owning the session to which stream belongs */
297 /* Network sequence number. Indicating on which relayd socket it goes. */
298 uint64_t net_seq_idx
;
300 * Indicate if this stream was successfully sent to a relayd. This is set
301 * after the refcount of the relayd is incremented and is checked when the
302 * stream is closed before decrementing the refcount in order to avoid an
305 unsigned int sent_to_relayd
;
307 /* Identify if the stream is the metadata */
308 unsigned int metadata_flag
;
309 /* Used when the stream is set for network streaming */
310 uint64_t relayd_stream_id
;
312 * When sending a stream packet to a relayd, this number is used to track
313 * the packet sent by the consumer and seen by the relayd. When sending the
314 * data header to the relayd, this number is sent and if the transmission
315 * was successful, it is incremented.
317 * Even if the full data is not fully transmitted it won't matter since
318 * only two possible error can happen after that where either the relayd
319 * died or a read error is detected on the stream making this value useless
322 * This value SHOULD be read/updated atomically or with the lock acquired.
324 uint64_t next_net_seq_num
;
326 * Lock to use the stream FDs since they are used between threads.
328 * This is nested INSIDE the consumer_data lock.
329 * This is nested INSIDE the metadata cache lock.
330 * This is nested INSIDE the channel lock.
331 * This is nested INSIDE the channel timer lock.
332 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
334 pthread_mutex_t lock
;
335 /* Tracing session id */
338 * Indicates if the stream end point is still active or not (network
339 * streaming or local file system). The thread "owning" the stream is
340 * handling this status and can be notified of a state change through the
341 * consumer data appropriate pipe.
343 enum consumer_endpoint_status endpoint_status
;
344 /* Stream name. Format is: <channel_name>_<cpu_number> */
345 char name
[LTTNG_SYMBOL_NAME_LEN
];
346 /* Internal state of libustctl. */
347 struct ustctl_consumer_stream
*ustream
;
348 struct cds_list_head send_node
;
349 /* On-disk circular buffer */
350 uint64_t tracefile_size_current
;
351 uint64_t tracefile_count_current
;
353 * Monitor or not the streams of this channel meaning this indicates if the
354 * streams should be sent to the data/metadata thread or added to the no
355 * monitor list of the channel.
357 unsigned int monitor
;
359 * Indicate if the stream is globally visible meaning that it has been
360 * added to the multiple hash tables. If *not* set, NO lock should be
361 * acquired in the destroy path.
363 unsigned int globally_visible
;
365 * Pipe to wake up the metadata poll thread when the UST metadata
368 int ust_metadata_poll_pipe
[2];
370 * How much metadata was read from the metadata cache and sent
373 uint64_t ust_metadata_pushed
;
375 * FD of the index file for this stream.
380 * Local pipe to extract data when using splice.
385 * Rendez-vous point between data and metadata stream in live mode.
387 pthread_cond_t metadata_rdv
;
388 pthread_mutex_t metadata_rdv_lock
;
390 /* Indicate if the stream still has some data to be read. */
391 unsigned int has_data
:1;
395 * Internal representation of a relayd socket pair.
397 struct consumer_relayd_sock_pair
{
398 /* Network sequence number. */
399 uint64_t net_seq_idx
;
400 /* Number of stream associated with this relayd */
401 unsigned int refcount
;
404 * This flag indicates whether or not we should destroy this object. The
405 * destruction should ONLY occurs when this flag is set and the refcount is
408 unsigned int destroy_flag
;
411 * Mutex protecting the control socket to avoid out of order packets
412 * between threads sending data to the relayd. Since metadata data is sent
413 * over that socket, at least two sendmsg() are needed (header + data)
414 * creating a race for packets to overlap between threads using it.
416 * This is nested INSIDE the consumer_data lock.
417 * This is nested INSIDE the stream lock.
419 pthread_mutex_t ctrl_sock_mutex
;
421 /* Control socket. Command and metadata are passed over it */
422 struct lttcomm_relayd_sock control_sock
;
425 * We don't need a mutex at this point since we only splice or write single
426 * large chunk of data with a header appended at the begining. Moreover,
427 * this socket is for now only used in a single thread.
429 struct lttcomm_relayd_sock data_sock
;
430 struct lttng_ht_node_u64 node
;
432 /* Session id on both sides for the sockets. */
433 uint64_t relayd_session_id
;
434 uint64_t sessiond_session_id
;
438 * UST consumer local data to the program. One or more instance per
441 struct lttng_consumer_local_data
{
443 * Function to call when data is available on a buffer.
444 * Returns the number of bytes read, or negative error value.
446 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
447 struct lttng_consumer_local_data
*ctx
);
449 * function to call when we receive a new channel, it receives a
450 * newly allocated channel, depending on the return code of this
451 * function, the new channel will be handled by the application
455 * > 0 (success, FD is kept by application)
456 * == 0 (success, FD is left to library)
459 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
461 * function to call when we receive a new stream, it receives a
462 * newly allocated stream, depending on the return code of this
463 * function, the new stream will be handled by the application
467 * > 0 (success, FD is kept by application)
468 * == 0 (success, FD is left to library)
471 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
473 * function to call when a stream is getting updated by the session
474 * daemon, this function receives the sessiond key and the new
475 * state, depending on the return code of this function the
476 * update of state for the stream is handled by the application
480 * > 0 (success, FD is kept by application)
481 * == 0 (success, FD is left to library)
484 int (*on_update_stream
)(uint64_t sessiond_key
, uint32_t state
);
485 enum lttng_consumer_type type
;
486 /* socket to communicate errors with sessiond */
487 int consumer_error_socket
;
488 /* socket to ask metadata to sessiond. */
489 int consumer_metadata_socket
;
491 * Protect consumer_metadata_socket.
493 * This is nested OUTSIDE the metadata cache lock.
495 pthread_mutex_t metadata_socket_lock
;
496 /* socket to exchange commands with sessiond */
497 char *consumer_command_sock_path
;
498 /* communication with splice */
499 int consumer_channel_pipe
[2];
500 /* Data stream poll thread pipe. To transfer data stream to the thread */
501 struct lttng_pipe
*consumer_data_pipe
;
504 * Data thread use that pipe to catch wakeup from read subbuffer that
505 * detects that there is still data to be read for the stream encountered.
506 * Before doing so, the stream is flagged to indicate that there is still
509 * Both pipes (read/write) are owned and used inside the data thread.
511 struct lttng_pipe
*consumer_wakeup_pipe
;
512 /* Indicate if the wakeup thread has been notified. */
513 unsigned int has_wakeup
:1;
515 /* to let the signal handler wake up the fd receiver thread */
516 int consumer_should_quit
[2];
517 /* Metadata poll thread pipe. Transfer metadata stream to it */
518 struct lttng_pipe
*consumer_metadata_pipe
;
522 * Library-level data. One instance per process.
524 struct lttng_consumer_global_data
{
526 * At this time, this lock is used to ensure coherence between the count
527 * and number of element in the hash table. It's also a protection for
528 * concurrent read/write between threads.
530 * This is nested OUTSIDE the stream lock.
531 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
533 pthread_mutex_t lock
;
536 * Number of streams in the data stream hash table declared outside.
537 * Protected by consumer_data.lock.
541 /* Channel hash table protected by consumer_data.lock. */
542 struct lttng_ht
*channel_ht
;
544 * Flag specifying if the local array of FDs needs update in the
545 * poll function. Protected by consumer_data.lock.
547 unsigned int need_update
;
548 enum lttng_consumer_type type
;
551 * Relayd socket(s) hashtable indexed by network sequence number. Each
552 * stream has an index which associate the right relayd socket to use.
554 struct lttng_ht
*relayd_ht
;
557 * This hash table contains all streams (metadata and data) indexed by
558 * session id. In other words, the ht is indexed by session id and each
559 * bucket contains the list of associated streams.
561 * This HT uses the "node_session_id" of the consumer stream.
563 struct lttng_ht
*stream_list_ht
;
566 * This HT uses the "node_channel_id" of the consumer stream.
568 struct lttng_ht
*stream_per_chan_id_ht
;
572 * Init consumer data structures.
574 int lttng_consumer_init(void);
577 * Set the error socket for communication with a session daemon.
579 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
583 * Set the command socket path for communication with a session daemon.
585 void lttng_consumer_set_command_sock_path(
586 struct lttng_consumer_local_data
*ctx
, char *sock
);
589 * Send return code to session daemon.
591 * Returns the return code of sendmsg : the number of bytes transmitted or -1
594 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
597 * Called from signal handler to ensure a clean exit.
599 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
602 * Cleanup the daemon's socket on exit.
604 void lttng_consumer_cleanup(void);
607 * Flush pending writes to trace output disk file.
609 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
613 * Poll on the should_quit pipe and the command socket return -1 on error and
614 * should exit, 0 if data is available on the command socket
616 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
618 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
620 enum lttng_consumer_stream_state state
,
621 const char *channel_name
,
628 enum consumer_channel_type type
,
629 unsigned int monitor
);
630 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
632 const char *pathname
,
637 enum lttng_event_output output
,
638 uint64_t tracefile_size
,
639 uint64_t tracefile_count
,
640 uint64_t session_id_per_pid
,
641 unsigned int monitor
,
642 unsigned int live_timer_interval
,
643 const char *root_shm_path
,
644 const char *shm_path
);
645 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
646 struct lttng_ht
*ht
);
647 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
648 struct lttng_ht
*ht
);
649 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
650 struct lttng_consumer_local_data
*ctx
);
651 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
653 /* lttng-relayd consumer command */
654 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
655 uint64_t net_seq_idx
);
656 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
657 int consumer_send_relayd_stream(struct lttng_consumer_stream
*stream
, char *path
);
658 int consumer_send_relayd_streams_sent(uint64_t net_seq_idx
);
659 void close_relayd_stream(struct lttng_consumer_stream
*stream
);
660 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
661 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
663 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
665 struct lttng_consumer_local_data
*lttng_consumer_create(
666 enum lttng_consumer_type type
,
667 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
668 struct lttng_consumer_local_data
*ctx
),
669 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
670 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
671 int (*update_stream
)(uint64_t sessiond_key
, uint32_t state
));
672 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
673 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
674 struct lttng_consumer_local_data
*ctx
,
675 struct lttng_consumer_stream
*stream
, unsigned long len
,
676 unsigned long padding
,
677 struct ctf_packet_index
*index
);
678 ssize_t
lttng_consumer_on_read_subbuffer_splice(
679 struct lttng_consumer_local_data
*ctx
,
680 struct lttng_consumer_stream
*stream
, unsigned long len
,
681 unsigned long padding
,
682 struct ctf_packet_index
*index
);
683 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
684 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
686 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream
*stream
);
687 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream
*stream
);
688 void *consumer_thread_metadata_poll(void *data
);
689 void *consumer_thread_data_poll(void *data
);
690 void *consumer_thread_sessiond_poll(void *data
);
691 void *consumer_thread_channel_poll(void *data
);
692 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
693 int sock
, struct pollfd
*consumer_sockpoll
);
695 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
696 struct lttng_consumer_local_data
*ctx
);
697 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
698 int consumer_add_relayd_socket(uint64_t net_seq_idx
, int sock_type
,
699 struct lttng_consumer_local_data
*ctx
, int sock
,
700 struct pollfd
*consumer_sockpoll
, struct lttcomm_relayd_sock
*relayd_sock
,
701 uint64_t sessiond_id
, uint64_t relayd_session_id
);
702 void consumer_flag_relayd_for_destroy(
703 struct consumer_relayd_sock_pair
*relayd
);
704 int consumer_data_pending(uint64_t id
);
705 int consumer_send_status_msg(int sock
, int ret_code
);
706 int consumer_send_status_channel(int sock
,
707 struct lttng_consumer_channel
*channel
);
708 void notify_thread_del_channel(struct lttng_consumer_local_data
*ctx
,
710 void consumer_destroy_relayd(struct consumer_relayd_sock_pair
*relayd
);
711 unsigned long consumer_get_consume_start_pos(unsigned long consumed_pos
,
712 unsigned long produced_pos
, uint64_t nb_packets_per_stream
,
713 uint64_t max_sb_size
);
714 int consumer_add_data_stream(struct lttng_consumer_stream
*stream
);
715 void consumer_del_stream_for_data(struct lttng_consumer_stream
*stream
);
716 int consumer_add_metadata_stream(struct lttng_consumer_stream
*stream
);
717 void consumer_del_stream_for_metadata(struct lttng_consumer_stream
*stream
);
718 int consumer_create_index_file(struct lttng_consumer_stream
*stream
);
720 #endif /* LIB_CONSUMER_H */