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/lttng-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 */
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
,
62 /* State of each fd in consumer */
63 enum lttng_consumer_stream_state
{
64 LTTNG_CONSUMER_ACTIVE_STREAM
,
65 LTTNG_CONSUMER_PAUSE_STREAM
,
66 LTTNG_CONSUMER_DELETE_STREAM
,
69 enum lttng_consumer_type
{
70 LTTNG_CONSUMER_UNKNOWN
= 0,
71 LTTNG_CONSUMER_KERNEL
,
76 enum consumer_endpoint_status
{
77 CONSUMER_ENDPOINT_ACTIVE
,
78 CONSUMER_ENDPOINT_INACTIVE
,
81 enum consumer_channel_output
{
82 CONSUMER_CHANNEL_MMAP
= 0,
83 CONSUMER_CHANNEL_SPLICE
= 1,
86 enum consumer_channel_type
{
87 CONSUMER_CHANNEL_TYPE_METADATA
= 0,
88 CONSUMER_CHANNEL_TYPE_DATA
= 1,
91 extern struct lttng_consumer_global_data consumer_data
;
94 struct cds_list_head head
;
99 struct consumer_metadata_cache
;
101 struct lttng_consumer_channel
{
102 /* HT node used for consumer_data.channel_ht */
103 struct lttng_ht_node_u64 node
;
104 /* Indexed key. Incremented value in the consumer. */
106 /* Number of streams referencing this channel */
108 /* Tracing session id on the session daemon side. */
111 * Session id when requesting metadata to the session daemon for
112 * a session with per-PID buffers.
114 uint64_t session_id_per_pid
;
115 /* Channel trace file path name. */
116 char pathname
[PATH_MAX
];
118 char name
[LTTNG_SYMBOL_NAME_LEN
];
119 /* UID and GID of the session owning this channel. */
122 /* Relayd id of the channel. -1ULL if it does not apply. */
125 * Number of streams NOT initialized yet. This is used in order to not
126 * delete this channel if streams are getting initialized.
128 unsigned int nb_init_stream_left
;
129 /* Output type (mmap or splice). */
130 enum consumer_channel_output output
;
131 /* Channel type for stream */
132 enum consumer_channel_type type
;
135 uid_t ust_app_uid
; /* Application UID. */
136 struct ustctl_consumer_channel
*uchan
;
137 unsigned char uuid
[UUID_STR_LEN
];
139 * Temporary stream list used to store the streams once created and waiting
140 * to be sent to the session daemon by receiving the
141 * LTTNG_CONSUMER_GET_CHANNEL.
143 struct stream_list streams
;
146 * Set if the channel is metadata. We keep a reference to the stream
147 * because we have to flush data once pushed by the session daemon. For a
148 * regular channel, this is always set to NULL.
150 struct lttng_consumer_stream
*metadata_stream
;
154 /* Node within channel thread ht */
155 struct lttng_ht_node_u64 wait_fd_node
;
157 /* Metadata cache is metadata channel */
158 struct consumer_metadata_cache
*metadata_cache
;
159 /* For metadata periodical flush */
160 int switch_timer_enabled
;
161 timer_t switch_timer
;
162 int switch_timer_error
;
164 /* On-disk circular buffer */
165 uint64_t tracefile_size
;
166 uint64_t tracefile_count
;
168 * Monitor or not the streams of this channel meaning this indicates if the
169 * streams should be sent to the data/metadata thread or added to the no
170 * monitor list of the channel.
172 unsigned int monitor
;
177 * This lock protects against concurrent update of channel.
179 * This is nested INSIDE the consumer data lock.
180 * This is nested OUTSIDE the channel timer lock.
181 * This is nested OUTSIDE the metadata cache lock.
182 * This is nested OUTSIDE stream lock.
183 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
185 pthread_mutex_t lock
;
188 * Channel teardown lock.
190 * This lock protect against teardown of channel. It is _never_
191 * taken by the timer handler.
193 * This is nested INSIDE the consumer data lock.
194 * This is nested INSIDE the channel lock.
195 * This is nested OUTSIDE the metadata cache lock.
196 * This is nested OUTSIDE stream lock.
197 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
199 pthread_mutex_t timer_lock
;
203 * Internal representation of the streams, sessiond_key is used to identify
206 struct lttng_consumer_stream
{
207 /* HT node used by the data_ht and metadata_ht */
208 struct lttng_ht_node_u64 node
;
209 /* stream indexed per channel key node */
210 struct lttng_ht_node_u64 node_channel_id
;
211 /* HT node used in consumer_data.stream_list_ht */
212 struct lttng_ht_node_u64 node_session_id
;
213 /* Pointer to associated channel. */
214 struct lttng_consumer_channel
*chan
;
216 /* Key by which the stream is indexed for 'node'. */
219 * File descriptor of the data output file. This can be either a file or a
220 * socket fd for relayd streaming.
222 int out_fd
; /* output file to write the data */
223 /* Write position in the output file descriptor */
225 /* Amount of bytes written to the output */
226 uint64_t output_written
;
227 enum lttng_consumer_stream_state state
;
230 int hangup_flush_done
;
231 enum lttng_event_output output
;
232 /* Maximum subbuffer size. */
233 unsigned long max_sb_size
;
236 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
237 * used for the mmap base and offset.
240 unsigned long mmap_len
;
245 /* UID/GID of the user owning the session to which stream belongs */
248 /* Network sequence number. Indicating on which relayd socket it goes. */
249 uint64_t net_seq_idx
;
251 * Indicate if this stream was successfully sent to a relayd. This is set
252 * after the refcount of the relayd is incremented and is checked when the
253 * stream is closed before decrementing the refcount in order to avoid an
256 unsigned int sent_to_relayd
;
258 /* Identify if the stream is the metadata */
259 unsigned int metadata_flag
;
260 /* Used when the stream is set for network streaming */
261 uint64_t relayd_stream_id
;
263 * When sending a stream packet to a relayd, this number is used to track
264 * the packet sent by the consumer and seen by the relayd. When sending the
265 * data header to the relayd, this number is sent and if the transmission
266 * was successful, it is incremented.
268 * Even if the full data is not fully transmitted it won't matter since
269 * only two possible error can happen after that where either the relayd
270 * died or a read error is detected on the stream making this value useless
273 * This value SHOULD be read/updated atomically or with the lock acquired.
275 uint64_t next_net_seq_num
;
277 * Lock to use the stream FDs since they are used between threads.
279 * This is nested INSIDE the consumer_data lock.
280 * This is nested INSIDE the metadata cache lock.
281 * This is nested INSIDE the channel lock.
282 * This is nested INSIDE the channel timer lock.
283 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
285 pthread_mutex_t lock
;
286 /* Tracing session id */
289 * Indicates if the stream end point is still active or not (network
290 * streaming or local file system). The thread "owning" the stream is
291 * handling this status and can be notified of a state change through the
292 * consumer data appropriate pipe.
294 enum consumer_endpoint_status endpoint_status
;
295 /* Stream name. Format is: <channel_name>_<cpu_number> */
296 char name
[LTTNG_SYMBOL_NAME_LEN
];
297 /* Internal state of libustctl. */
298 struct ustctl_consumer_stream
*ustream
;
299 struct cds_list_head send_node
;
300 /* On-disk circular buffer */
301 uint64_t tracefile_size_current
;
302 uint64_t tracefile_count_current
;
304 * Monitor or not the streams of this channel meaning this indicates if the
305 * streams should be sent to the data/metadata thread or added to the no
306 * monitor list of the channel.
308 unsigned int monitor
;
310 * Indicate if the stream is globally visible meaning that it has been
311 * added to the multiple hash tables. If *not* set, NO lock should be
312 * acquired in the destroy path.
314 unsigned int globally_visible
;
316 * Pipe to wake up the metadata poll thread when the UST metadata
319 int ust_metadata_poll_pipe
[2];
321 * How much metadata was read from the metadata cache and sent
324 uint64_t ust_metadata_pushed
;
326 * FD of the index file for this stream.
332 * Internal representation of a relayd socket pair.
334 struct consumer_relayd_sock_pair
{
335 /* Network sequence number. */
336 uint64_t net_seq_idx
;
337 /* Number of stream associated with this relayd */
338 unsigned int refcount
;
341 * This flag indicates whether or not we should destroy this object. The
342 * destruction should ONLY occurs when this flag is set and the refcount is
345 unsigned int destroy_flag
;
348 * Mutex protecting the control socket to avoid out of order packets
349 * between threads sending data to the relayd. Since metadata data is sent
350 * over that socket, at least two sendmsg() are needed (header + data)
351 * creating a race for packets to overlap between threads using it.
353 * This is nested INSIDE the consumer_data lock.
354 * This is nested INSIDE the stream lock.
356 pthread_mutex_t ctrl_sock_mutex
;
358 /* Control socket. Command and metadata are passed over it */
359 struct lttcomm_relayd_sock control_sock
;
362 * We don't need a mutex at this point since we only splice or write single
363 * large chunk of data with a header appended at the begining. Moreover,
364 * this socket is for now only used in a single thread.
366 struct lttcomm_relayd_sock data_sock
;
367 struct lttng_ht_node_u64 node
;
369 /* Session id on both sides for the sockets. */
370 uint64_t relayd_session_id
;
371 uint64_t sessiond_session_id
;
375 * UST consumer local data to the program. One or more instance per
378 struct lttng_consumer_local_data
{
380 * Function to call when data is available on a buffer.
381 * Returns the number of bytes read, or negative error value.
383 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
384 struct lttng_consumer_local_data
*ctx
);
386 * function to call when we receive a new channel, it receives a
387 * newly allocated channel, depending on the return code of this
388 * function, the new channel will be handled by the application
392 * > 0 (success, FD is kept by application)
393 * == 0 (success, FD is left to library)
396 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
398 * function to call when we receive a new stream, it receives a
399 * newly allocated stream, depending on the return code of this
400 * function, the new stream will be handled by the application
404 * > 0 (success, FD is kept by application)
405 * == 0 (success, FD is left to library)
408 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
410 * function to call when a stream is getting updated by the session
411 * daemon, this function receives the sessiond key and the new
412 * state, depending on the return code of this function the
413 * update of state for the stream is handled by the application
417 * > 0 (success, FD is kept by application)
418 * == 0 (success, FD is left to library)
421 int (*on_update_stream
)(uint64_t sessiond_key
, uint32_t state
);
422 enum lttng_consumer_type type
;
423 /* socket to communicate errors with sessiond */
424 int consumer_error_socket
;
425 /* socket to ask metadata to sessiond. */
426 int consumer_metadata_socket
;
428 * Protect consumer_metadata_socket.
430 * This is nested OUTSIDE the metadata cache lock.
432 pthread_mutex_t metadata_socket_lock
;
433 /* socket to exchange commands with sessiond */
434 char *consumer_command_sock_path
;
435 /* communication with splice */
436 int consumer_thread_pipe
[2];
437 int consumer_channel_pipe
[2];
438 int consumer_splice_metadata_pipe
[2];
439 /* Data stream poll thread pipe. To transfer data stream to the thread */
440 struct lttng_pipe
*consumer_data_pipe
;
441 /* to let the signal handler wake up the fd receiver thread */
442 int consumer_should_quit
[2];
443 /* Metadata poll thread pipe. Transfer metadata stream to it */
444 struct lttng_pipe
*consumer_metadata_pipe
;
448 * Library-level data. One instance per process.
450 struct lttng_consumer_global_data
{
452 * At this time, this lock is used to ensure coherence between the count
453 * and number of element in the hash table. It's also a protection for
454 * concurrent read/write between threads.
456 * This is nested OUTSIDE the stream lock.
457 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
459 pthread_mutex_t lock
;
462 * Number of streams in the data stream hash table declared outside.
463 * Protected by consumer_data.lock.
467 /* Channel hash table protected by consumer_data.lock. */
468 struct lttng_ht
*channel_ht
;
470 * Flag specifying if the local array of FDs needs update in the
471 * poll function. Protected by consumer_data.lock.
473 unsigned int need_update
;
474 enum lttng_consumer_type type
;
477 * Relayd socket(s) hashtable indexed by network sequence number. Each
478 * stream has an index which associate the right relayd socket to use.
480 struct lttng_ht
*relayd_ht
;
483 * This hash table contains all streams (metadata and data) indexed by
484 * session id. In other words, the ht is indexed by session id and each
485 * bucket contains the list of associated streams.
487 * This HT uses the "node_session_id" of the consumer stream.
489 struct lttng_ht
*stream_list_ht
;
492 * This HT uses the "node_channel_id" of the consumer stream.
494 struct lttng_ht
*stream_per_chan_id_ht
;
498 * Init consumer data structures.
500 void lttng_consumer_init(void);
503 * Set the error socket for communication with a session daemon.
505 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
509 * Set the command socket path for communication with a session daemon.
511 void lttng_consumer_set_command_sock_path(
512 struct lttng_consumer_local_data
*ctx
, char *sock
);
515 * Send return code to session daemon.
517 * Returns the return code of sendmsg : the number of bytes transmitted or -1
520 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
523 * Called from signal handler to ensure a clean exit.
525 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
528 * Cleanup the daemon's socket on exit.
530 void lttng_consumer_cleanup(void);
533 * Flush pending writes to trace output disk file.
535 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
539 * Poll on the should_quit pipe and the command socket return -1 on error and
540 * should exit, 0 if data is available on the command socket
542 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
544 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
546 enum lttng_consumer_stream_state state
,
547 const char *channel_name
,
554 enum consumer_channel_type type
,
555 unsigned int monitor
);
556 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
558 const char *pathname
,
563 enum lttng_event_output output
,
564 uint64_t tracefile_size
,
565 uint64_t tracefile_count
,
566 uint64_t session_id_per_pid
,
567 unsigned int monitor
);
568 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
569 struct lttng_ht
*ht
);
570 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
571 struct lttng_ht
*ht
);
572 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
573 struct lttng_consumer_local_data
*ctx
);
574 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
576 /* lttng-relayd consumer command */
577 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
578 uint64_t net_seq_idx
);
579 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
580 int consumer_send_relayd_stream(struct lttng_consumer_stream
*stream
, char *path
);
581 void close_relayd_stream(struct lttng_consumer_stream
*stream
);
582 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
583 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
585 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
587 struct lttng_consumer_local_data
*lttng_consumer_create(
588 enum lttng_consumer_type type
,
589 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
590 struct lttng_consumer_local_data
*ctx
),
591 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
592 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
593 int (*update_stream
)(uint64_t sessiond_key
, uint32_t state
));
594 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
595 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
596 struct lttng_consumer_local_data
*ctx
,
597 struct lttng_consumer_stream
*stream
, unsigned long len
,
598 unsigned long padding
,
599 struct lttng_packet_index
*index
);
600 ssize_t
lttng_consumer_on_read_subbuffer_splice(
601 struct lttng_consumer_local_data
*ctx
,
602 struct lttng_consumer_stream
*stream
, unsigned long len
,
603 unsigned long padding
,
604 struct lttng_packet_index
*index
);
605 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
606 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
608 void *consumer_thread_metadata_poll(void *data
);
609 void *consumer_thread_data_poll(void *data
);
610 void *consumer_thread_sessiond_poll(void *data
);
611 void *consumer_thread_channel_poll(void *data
);
612 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
613 int sock
, struct pollfd
*consumer_sockpoll
);
615 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
616 struct lttng_consumer_local_data
*ctx
);
617 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
618 int consumer_add_relayd_socket(uint64_t net_seq_idx
, int sock_type
,
619 struct lttng_consumer_local_data
*ctx
, int sock
,
620 struct pollfd
*consumer_sockpoll
, struct lttcomm_relayd_sock
*relayd_sock
,
621 uint64_t sessiond_id
);
622 void consumer_flag_relayd_for_destroy(
623 struct consumer_relayd_sock_pair
*relayd
);
624 int consumer_data_pending(uint64_t id
);
625 int consumer_send_status_msg(int sock
, int ret_code
);
626 int consumer_send_status_channel(int sock
,
627 struct lttng_consumer_channel
*channel
);
628 void notify_thread_del_channel(struct lttng_consumer_local_data
*ctx
,
630 void consumer_destroy_relayd(struct consumer_relayd_sock_pair
*relayd
);
631 unsigned long consumer_get_consumed_maxsize(unsigned long consumed_pos
,
632 unsigned long produced_pos
, uint64_t max_stream_size
);
633 int consumer_add_data_stream(struct lttng_consumer_stream
*stream
);
634 void consumer_del_stream_for_data(struct lttng_consumer_stream
*stream
);
635 int consumer_add_metadata_stream(struct lttng_consumer_stream
*stream
);
636 void consumer_del_stream_for_metadata(struct lttng_consumer_stream
*stream
);
637 int consumer_create_index_file(struct lttng_consumer_stream
*stream
);
639 #endif /* LIB_CONSUMER_H */