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_DISCARDED_EVENTS
,
62 LTTNG_CONSUMER_LOST_PACKETS
,
65 /* State of each fd in consumer */
66 enum lttng_consumer_stream_state
{
67 LTTNG_CONSUMER_ACTIVE_STREAM
,
68 LTTNG_CONSUMER_PAUSE_STREAM
,
69 LTTNG_CONSUMER_DELETE_STREAM
,
72 enum lttng_consumer_type
{
73 LTTNG_CONSUMER_UNKNOWN
= 0,
74 LTTNG_CONSUMER_KERNEL
,
79 enum consumer_endpoint_status
{
80 CONSUMER_ENDPOINT_ACTIVE
,
81 CONSUMER_ENDPOINT_INACTIVE
,
84 enum consumer_channel_output
{
85 CONSUMER_CHANNEL_MMAP
= 0,
86 CONSUMER_CHANNEL_SPLICE
= 1,
89 enum consumer_channel_type
{
90 CONSUMER_CHANNEL_TYPE_METADATA
= 0,
91 CONSUMER_CHANNEL_TYPE_DATA
= 1,
94 extern struct lttng_consumer_global_data consumer_data
;
97 struct cds_list_head head
;
102 struct consumer_metadata_cache
;
104 struct lttng_consumer_channel
{
105 /* HT node used for consumer_data.channel_ht */
106 struct lttng_ht_node_u64 node
;
107 /* Indexed key. Incremented value in the consumer. */
109 /* Number of streams referencing this channel */
111 /* Tracing session id on the session daemon side. */
114 * Session id when requesting metadata to the session daemon for
115 * a session with per-PID buffers.
117 uint64_t session_id_per_pid
;
118 /* Channel trace file path name. */
119 char pathname
[PATH_MAX
];
121 char name
[LTTNG_SYMBOL_NAME_LEN
];
122 /* UID and GID of the session owning this channel. */
125 /* Relayd id of the channel. -1ULL if it does not apply. */
128 * Number of streams NOT initialized yet. This is used in order to not
129 * delete this channel if streams are getting initialized.
131 unsigned int nb_init_stream_left
;
132 /* Output type (mmap or splice). */
133 enum consumer_channel_output output
;
134 /* Channel type for stream */
135 enum consumer_channel_type type
;
138 uid_t ust_app_uid
; /* Application UID. */
139 struct ustctl_consumer_channel
*uchan
;
140 unsigned char uuid
[UUID_STR_LEN
];
142 * Temporary stream list used to store the streams once created and waiting
143 * to be sent to the session daemon by receiving the
144 * LTTNG_CONSUMER_GET_CHANNEL.
146 struct stream_list streams
;
149 * Set if the channel is metadata. We keep a reference to the stream
150 * because we have to flush data once pushed by the session daemon. For a
151 * regular channel, this is always set to NULL.
153 struct lttng_consumer_stream
*metadata_stream
;
157 /* Node within channel thread ht */
158 struct lttng_ht_node_u64 wait_fd_node
;
160 /* Metadata cache is metadata channel */
161 struct consumer_metadata_cache
*metadata_cache
;
162 /* For UST metadata periodical flush */
163 int switch_timer_enabled
;
164 timer_t switch_timer
;
165 int switch_timer_error
;
167 /* For the live mode */
168 int live_timer_enabled
;
170 int live_timer_error
;
172 /* On-disk circular buffer */
173 uint64_t tracefile_size
;
174 uint64_t tracefile_count
;
176 * Monitor or not the streams of this channel meaning this indicates if the
177 * streams should be sent to the data/metadata thread or added to the no
178 * monitor list of the channel.
180 unsigned int monitor
;
185 * This lock protects against concurrent update of channel.
187 * This is nested INSIDE the consumer data lock.
188 * This is nested OUTSIDE the channel timer lock.
189 * This is nested OUTSIDE the metadata cache lock.
190 * This is nested OUTSIDE stream lock.
191 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
193 pthread_mutex_t lock
;
196 * Channel teardown lock.
198 * This lock protect against teardown of channel. It is _never_
199 * taken by the timer handler.
201 * This is nested INSIDE the consumer data lock.
202 * This is nested INSIDE the channel lock.
203 * This is nested OUTSIDE the metadata cache lock.
204 * This is nested OUTSIDE stream lock.
205 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
207 pthread_mutex_t timer_lock
;
209 /* Timer value in usec for live streaming. */
210 unsigned int live_timer_interval
;
214 char root_shm_path
[PATH_MAX
];
215 char shm_path
[PATH_MAX
];
216 /* Total number of discarded events for that channel. */
217 uint64_t discarded_events
;
218 /* Total number of missed packets due to overwriting (overwrite). */
219 uint64_t lost_packets
;
223 * Internal representation of the streams, sessiond_key is used to identify
226 struct lttng_consumer_stream
{
227 /* HT node used by the data_ht and metadata_ht */
228 struct lttng_ht_node_u64 node
;
229 /* stream indexed per channel key node */
230 struct lttng_ht_node_u64 node_channel_id
;
231 /* HT node used in consumer_data.stream_list_ht */
232 struct lttng_ht_node_u64 node_session_id
;
233 /* Pointer to associated channel. */
234 struct lttng_consumer_channel
*chan
;
236 /* Key by which the stream is indexed for 'node'. */
239 * File descriptor of the data output file. This can be either a file or a
240 * socket fd for relayd streaming.
242 int out_fd
; /* output file to write the data */
243 /* Write position in the output file descriptor */
245 /* Amount of bytes written to the output */
246 uint64_t output_written
;
247 enum lttng_consumer_stream_state state
;
250 int hangup_flush_done
;
253 * metadata_timer_lock protects flags waiting_on_metadata and
254 * missed_metadata_flush.
256 pthread_mutex_t metadata_timer_lock
;
258 * Flag set when awaiting metadata to be pushed. Used in the
259 * timer thread to skip waiting on the stream (and stream lock) to
260 * ensure we can proceed to flushing metadata in live mode.
262 bool waiting_on_metadata
;
263 /* Raised when a timer misses a metadata flush. */
264 bool missed_metadata_flush
;
266 enum lttng_event_output output
;
267 /* Maximum subbuffer size. */
268 unsigned long max_sb_size
;
271 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
272 * used for the mmap base and offset.
275 unsigned long mmap_len
;
280 /* UID/GID of the user owning the session to which stream belongs */
283 /* Network sequence number. Indicating on which relayd socket it goes. */
284 uint64_t net_seq_idx
;
286 * Indicate if this stream was successfully sent to a relayd. This is set
287 * after the refcount of the relayd is incremented and is checked when the
288 * stream is closed before decrementing the refcount in order to avoid an
291 unsigned int sent_to_relayd
;
293 /* Identify if the stream is the metadata */
294 unsigned int metadata_flag
;
296 * Last known metadata version, reset the metadata file in case
299 uint64_t metadata_version
;
300 /* Used when the stream is set for network streaming */
301 uint64_t relayd_stream_id
;
303 * When sending a stream packet to a relayd, this number is used to track
304 * the packet sent by the consumer and seen by the relayd. When sending the
305 * data header to the relayd, this number is sent and if the transmission
306 * was successful, it is incremented.
308 * Even if the full data is not fully transmitted it won't matter since
309 * only two possible error can happen after that where either the relayd
310 * died or a read error is detected on the stream making this value useless
313 * This value SHOULD be read/updated atomically or with the lock acquired.
315 uint64_t next_net_seq_num
;
317 * Lock to use the stream FDs since they are used between threads.
319 * This is nested INSIDE the consumer_data lock.
320 * This is nested INSIDE the metadata cache lock.
321 * This is nested INSIDE the channel lock.
322 * This is nested INSIDE the channel timer lock.
323 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
325 pthread_mutex_t lock
;
326 /* Tracing session id */
329 * Indicates if the stream end point is still active or not (network
330 * streaming or local file system). The thread "owning" the stream is
331 * handling this status and can be notified of a state change through the
332 * consumer data appropriate pipe.
334 enum consumer_endpoint_status endpoint_status
;
335 /* Stream name. Format is: <channel_name>_<cpu_number> */
336 char name
[LTTNG_SYMBOL_NAME_LEN
];
337 /* Internal state of libustctl. */
338 struct ustctl_consumer_stream
*ustream
;
339 struct cds_list_head send_node
;
340 /* On-disk circular buffer */
341 uint64_t tracefile_size_current
;
342 uint64_t tracefile_count_current
;
344 * Monitor or not the streams of this channel meaning this indicates if the
345 * streams should be sent to the data/metadata thread or added to the no
346 * monitor list of the channel.
348 unsigned int monitor
;
350 * Indicate if the stream is globally visible meaning that it has been
351 * added to the multiple hash tables. If *not* set, NO lock should be
352 * acquired in the destroy path.
354 unsigned int globally_visible
;
356 * Pipe to wake up the metadata poll thread when the UST metadata
359 int ust_metadata_poll_pipe
[2];
361 * How much metadata was read from the metadata cache and sent
364 uint64_t ust_metadata_pushed
;
366 * Copy of the last discarded event value to detect the overflow of
369 uint64_t last_discarded_events
;
370 /* Copy of the sequence number of the last packet extracted. */
371 uint64_t last_sequence_number
;
373 * FD of the index file for this stream.
378 * Local pipe to extract data when using splice.
383 * Rendez-vous point between data and metadata stream in live mode.
385 pthread_cond_t metadata_rdv
;
386 pthread_mutex_t metadata_rdv_lock
;
388 /* Indicate if the stream still has some data to be read. */
389 unsigned int has_data
:1;
391 * Inform the consumer or relay to reset the metadata
392 * file before writing in it (regeneration).
394 unsigned int reset_metadata_flag
:1;
398 * Internal representation of a relayd socket pair.
400 struct consumer_relayd_sock_pair
{
401 /* Network sequence number. */
402 uint64_t net_seq_idx
;
403 /* Number of stream associated with this relayd */
404 unsigned int refcount
;
407 * This flag indicates whether or not we should destroy this object. The
408 * destruction should ONLY occurs when this flag is set and the refcount is
411 unsigned int destroy_flag
;
414 * Mutex protecting the control socket to avoid out of order packets
415 * between threads sending data to the relayd. Since metadata data is sent
416 * over that socket, at least two sendmsg() are needed (header + data)
417 * creating a race for packets to overlap between threads using it.
419 * This is nested INSIDE the consumer_data lock.
420 * This is nested INSIDE the stream lock.
422 pthread_mutex_t ctrl_sock_mutex
;
424 /* Control socket. Command and metadata are passed over it */
425 struct lttcomm_relayd_sock control_sock
;
428 * We don't need a mutex at this point since we only splice or write single
429 * large chunk of data with a header appended at the begining. Moreover,
430 * this socket is for now only used in a single thread.
432 struct lttcomm_relayd_sock data_sock
;
433 struct lttng_ht_node_u64 node
;
435 /* Session id on both sides for the sockets. */
436 uint64_t relayd_session_id
;
437 uint64_t sessiond_session_id
;
441 * UST consumer local data to the program. One or more instance per
444 struct lttng_consumer_local_data
{
446 * Function to call when data is available on a buffer.
447 * Returns the number of bytes read, or negative error value.
449 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
450 struct lttng_consumer_local_data
*ctx
);
452 * function to call when we receive a new channel, it receives a
453 * newly allocated channel, depending on the return code of this
454 * function, the new channel will be handled by the application
458 * > 0 (success, FD is kept by application)
459 * == 0 (success, FD is left to library)
462 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
464 * function to call when we receive a new stream, it receives a
465 * newly allocated stream, depending on the return code of this
466 * function, the new stream will be handled by the application
470 * > 0 (success, FD is kept by application)
471 * == 0 (success, FD is left to library)
474 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
476 * function to call when a stream is getting updated by the session
477 * daemon, this function receives the sessiond key and the new
478 * state, depending on the return code of this function the
479 * update of state for the stream is handled by the application
483 * > 0 (success, FD is kept by application)
484 * == 0 (success, FD is left to library)
487 int (*on_update_stream
)(uint64_t sessiond_key
, uint32_t state
);
488 enum lttng_consumer_type type
;
489 /* socket to communicate errors with sessiond */
490 int consumer_error_socket
;
491 /* socket to ask metadata to sessiond. */
492 int consumer_metadata_socket
;
494 * Protect consumer_metadata_socket.
496 * This is nested OUTSIDE the metadata cache lock.
498 pthread_mutex_t metadata_socket_lock
;
499 /* socket to exchange commands with sessiond */
500 char *consumer_command_sock_path
;
501 /* communication with splice */
502 int consumer_channel_pipe
[2];
503 /* Data stream poll thread pipe. To transfer data stream to the thread */
504 struct lttng_pipe
*consumer_data_pipe
;
507 * Data thread use that pipe to catch wakeup from read subbuffer that
508 * detects that there is still data to be read for the stream encountered.
509 * Before doing so, the stream is flagged to indicate that there is still
512 * Both pipes (read/write) are owned and used inside the data thread.
514 struct lttng_pipe
*consumer_wakeup_pipe
;
515 /* Indicate if the wakeup thread has been notified. */
516 unsigned int has_wakeup
:1;
518 /* to let the signal handler wake up the fd receiver thread */
519 int consumer_should_quit
[2];
520 /* Metadata poll thread pipe. Transfer metadata stream to it */
521 struct lttng_pipe
*consumer_metadata_pipe
;
525 * Library-level data. One instance per process.
527 struct lttng_consumer_global_data
{
529 * At this time, this lock is used to ensure coherence between the count
530 * and number of element in the hash table. It's also a protection for
531 * concurrent read/write between threads.
533 * This is nested OUTSIDE the stream lock.
534 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
536 pthread_mutex_t lock
;
539 * Number of streams in the data stream hash table declared outside.
540 * Protected by consumer_data.lock.
544 /* Channel hash table protected by consumer_data.lock. */
545 struct lttng_ht
*channel_ht
;
547 * Flag specifying if the local array of FDs needs update in the
548 * poll function. Protected by consumer_data.lock.
550 unsigned int need_update
;
551 enum lttng_consumer_type type
;
554 * Relayd socket(s) hashtable indexed by network sequence number. Each
555 * stream has an index which associate the right relayd socket to use.
557 struct lttng_ht
*relayd_ht
;
560 * This hash table contains all streams (metadata and data) indexed by
561 * session id. In other words, the ht is indexed by session id and each
562 * bucket contains the list of associated streams.
564 * This HT uses the "node_session_id" of the consumer stream.
566 struct lttng_ht
*stream_list_ht
;
569 * This HT uses the "node_channel_id" of the consumer stream.
571 struct lttng_ht
*stream_per_chan_id_ht
;
575 * Init consumer data structures.
577 int lttng_consumer_init(void);
580 * Set the error socket for communication with a session daemon.
582 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
586 * Set the command socket path for communication with a session daemon.
588 void lttng_consumer_set_command_sock_path(
589 struct lttng_consumer_local_data
*ctx
, char *sock
);
592 * Send return code to session daemon.
594 * Returns the return code of sendmsg : the number of bytes transmitted or -1
597 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
600 * Called from signal handler to ensure a clean exit.
602 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
605 * Cleanup the daemon's socket on exit.
607 void lttng_consumer_cleanup(void);
610 * Flush pending writes to trace output disk file.
612 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
616 * Poll on the should_quit pipe and the command socket return -1 on error and
617 * should exit, 0 if data is available on the command socket
619 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
621 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
623 enum lttng_consumer_stream_state state
,
624 const char *channel_name
,
631 enum consumer_channel_type type
,
632 unsigned int monitor
);
633 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
635 const char *pathname
,
640 enum lttng_event_output output
,
641 uint64_t tracefile_size
,
642 uint64_t tracefile_count
,
643 uint64_t session_id_per_pid
,
644 unsigned int monitor
,
645 unsigned int live_timer_interval
,
646 const char *root_shm_path
,
647 const char *shm_path
);
648 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
649 struct lttng_ht
*ht
);
650 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
651 struct lttng_ht
*ht
);
652 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
653 struct lttng_consumer_local_data
*ctx
);
654 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
656 /* lttng-relayd consumer command */
657 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
658 int consumer_send_relayd_stream(struct lttng_consumer_stream
*stream
, char *path
);
659 int consumer_send_relayd_streams_sent(uint64_t net_seq_idx
);
660 void close_relayd_stream(struct lttng_consumer_stream
*stream
);
661 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
662 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
664 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
666 struct lttng_consumer_local_data
*lttng_consumer_create(
667 enum lttng_consumer_type type
,
668 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
669 struct lttng_consumer_local_data
*ctx
),
670 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
671 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
672 int (*update_stream
)(uint64_t sessiond_key
, uint32_t state
));
673 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
674 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
675 struct lttng_consumer_local_data
*ctx
,
676 struct lttng_consumer_stream
*stream
, unsigned long len
,
677 unsigned long padding
,
678 struct ctf_packet_index
*index
);
679 ssize_t
lttng_consumer_on_read_subbuffer_splice(
680 struct lttng_consumer_local_data
*ctx
,
681 struct lttng_consumer_stream
*stream
, unsigned long len
,
682 unsigned long padding
,
683 struct ctf_packet_index
*index
);
684 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
685 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
687 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream
*stream
);
688 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream
*stream
);
689 void *consumer_thread_metadata_poll(void *data
);
690 void *consumer_thread_data_poll(void *data
);
691 void *consumer_thread_sessiond_poll(void *data
);
692 void *consumer_thread_channel_poll(void *data
);
693 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
694 int sock
, struct pollfd
*consumer_sockpoll
);
696 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
697 struct lttng_consumer_local_data
*ctx
);
698 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
699 int consumer_add_relayd_socket(uint64_t net_seq_idx
, int sock_type
,
700 struct lttng_consumer_local_data
*ctx
, int sock
,
701 struct pollfd
*consumer_sockpoll
, struct lttcomm_relayd_sock
*relayd_sock
,
702 uint64_t sessiond_id
, uint64_t relayd_session_id
);
703 void consumer_flag_relayd_for_destroy(
704 struct consumer_relayd_sock_pair
*relayd
);
705 int consumer_data_pending(uint64_t id
);
706 int consumer_send_status_msg(int sock
, int ret_code
);
707 int consumer_send_status_channel(int sock
,
708 struct lttng_consumer_channel
*channel
);
709 void notify_thread_del_channel(struct lttng_consumer_local_data
*ctx
,
711 void consumer_destroy_relayd(struct consumer_relayd_sock_pair
*relayd
);
712 unsigned long consumer_get_consume_start_pos(unsigned long consumed_pos
,
713 unsigned long produced_pos
, uint64_t nb_packets_per_stream
,
714 uint64_t max_sb_size
);
715 int consumer_add_data_stream(struct lttng_consumer_stream
*stream
);
716 void consumer_del_stream_for_data(struct lttng_consumer_stream
*stream
);
717 int consumer_add_metadata_stream(struct lttng_consumer_stream
*stream
);
718 void consumer_del_stream_for_metadata(struct lttng_consumer_stream
*stream
);
719 int consumer_create_index_file(struct lttng_consumer_stream
*stream
);
721 #endif /* LIB_CONSUMER_H */