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>
36 /* Commands for consumer */
37 enum lttng_consumer_command
{
38 LTTNG_CONSUMER_ADD_CHANNEL
,
39 LTTNG_CONSUMER_ADD_STREAM
,
40 /* pause, delete, active depending on fd state */
41 LTTNG_CONSUMER_UPDATE_STREAM
,
42 /* inform the consumer to quit when all fd has hang up */
44 LTTNG_CONSUMER_ADD_RELAYD_SOCKET
,
45 /* Inform the consumer to kill a specific relayd connection */
46 LTTNG_CONSUMER_DESTROY_RELAYD
,
47 /* Return to the sessiond if there is data pending for a session */
48 LTTNG_CONSUMER_DATA_PENDING
,
49 /* Consumer creates a channel and returns it to sessiond. */
50 LTTNG_CONSUMER_ASK_CHANNEL_CREATION
,
51 LTTNG_CONSUMER_GET_CHANNEL
,
52 LTTNG_CONSUMER_DESTROY_CHANNEL
,
53 LTTNG_CONSUMER_PUSH_METADATA
,
54 LTTNG_CONSUMER_CLOSE_METADATA
,
55 LTTNG_CONSUMER_SETUP_METADATA
,
56 LTTNG_CONSUMER_FLUSH_CHANNEL
,
57 LTTNG_CONSUMER_SNAPSHOT_CHANNEL
,
58 LTTNG_CONSUMER_SNAPSHOT_METADATA
,
61 /* State of each fd in consumer */
62 enum lttng_consumer_stream_state
{
63 LTTNG_CONSUMER_ACTIVE_STREAM
,
64 LTTNG_CONSUMER_PAUSE_STREAM
,
65 LTTNG_CONSUMER_DELETE_STREAM
,
68 enum lttng_consumer_type
{
69 LTTNG_CONSUMER_UNKNOWN
= 0,
70 LTTNG_CONSUMER_KERNEL
,
75 enum consumer_endpoint_status
{
76 CONSUMER_ENDPOINT_ACTIVE
,
77 CONSUMER_ENDPOINT_INACTIVE
,
80 enum consumer_channel_output
{
81 CONSUMER_CHANNEL_MMAP
= 0,
82 CONSUMER_CHANNEL_SPLICE
= 1,
85 enum consumer_channel_type
{
86 CONSUMER_CHANNEL_TYPE_METADATA
= 0,
87 CONSUMER_CHANNEL_TYPE_DATA
= 1,
90 extern struct lttng_consumer_global_data consumer_data
;
93 struct cds_list_head head
;
98 struct consumer_metadata_cache
;
100 struct lttng_consumer_channel
{
101 /* HT node used for consumer_data.channel_ht */
102 struct lttng_ht_node_u64 node
;
103 /* Indexed key. Incremented value in the consumer. */
105 /* Number of streams referencing this channel */
107 /* Tracing session id on the session daemon side. */
110 * Session id when requesting metadata to the session daemon for
111 * a session with per-PID buffers.
113 uint64_t session_id_per_pid
;
114 /* Channel trace file path name. */
115 char pathname
[PATH_MAX
];
117 char name
[LTTNG_SYMBOL_NAME_LEN
];
118 /* UID and GID of the channel. */
121 /* Relayd id of the channel. -1ULL if it does not apply. */
124 * Number of streams NOT initialized yet. This is used in order to not
125 * delete this channel if streams are getting initialized.
127 unsigned int nb_init_stream_left
;
128 /* Output type (mmap or splice). */
129 enum consumer_channel_output output
;
130 /* Channel type for stream */
131 enum consumer_channel_type type
;
134 struct ustctl_consumer_channel
*uchan
;
135 unsigned char uuid
[UUID_STR_LEN
];
137 * Temporary stream list used to store the streams once created and waiting
138 * to be sent to the session daemon by receiving the
139 * LTTNG_CONSUMER_GET_CHANNEL.
141 struct stream_list streams
;
144 * Set if the channel is metadata. We keep a reference to the stream
145 * because we have to flush data once pushed by the session daemon. For a
146 * regular channel, this is always set to NULL.
148 struct lttng_consumer_stream
*metadata_stream
;
152 /* Node within channel thread ht */
153 struct lttng_ht_node_u64 wait_fd_node
;
155 /* Metadata cache is metadata channel */
156 struct consumer_metadata_cache
*metadata_cache
;
157 /* For metadata periodical flush */
158 int switch_timer_enabled
;
159 timer_t switch_timer
;
160 int switch_timer_error
;
162 /* On-disk circular buffer */
163 uint64_t tracefile_size
;
164 uint64_t tracefile_count
;
166 * Monitor or not the streams of this channel meaning this indicates if the
167 * streams should be sent to the data/metadata thread or added to the no
168 * monitor list of the channel.
170 unsigned int monitor
;
175 * This lock protects against concurrent update of channel.
177 * This is nested INSIDE the consumer data lock.
178 * This is nested OUTSIDE the channel timer lock.
179 * This is nested OUTSIDE the metadata cache lock.
180 * This is nested OUTSIDE stream lock.
181 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
183 pthread_mutex_t lock
;
186 * Channel teardown lock.
188 * This lock protect against teardown of channel. It is _never_
189 * taken by the timer handler.
191 * This is nested INSIDE the consumer data lock.
192 * This is nested INSIDE the channel lock.
193 * This is nested OUTSIDE the metadata cache lock.
194 * This is nested OUTSIDE stream lock.
195 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
197 pthread_mutex_t timer_lock
;
201 * Internal representation of the streams, sessiond_key is used to identify
204 struct lttng_consumer_stream
{
205 /* HT node used by the data_ht and metadata_ht */
206 struct lttng_ht_node_u64 node
;
207 /* stream indexed per channel key node */
208 struct lttng_ht_node_u64 node_channel_id
;
209 /* HT node used in consumer_data.stream_list_ht */
210 struct lttng_ht_node_u64 node_session_id
;
211 /* Pointer to associated channel. */
212 struct lttng_consumer_channel
*chan
;
214 /* Key by which the stream is indexed for 'node'. */
217 * File descriptor of the data output file. This can be either a file or a
218 * socket fd for relayd streaming.
220 int out_fd
; /* output file to write the data */
221 /* Write position in the output file descriptor */
223 enum lttng_consumer_stream_state state
;
226 int hangup_flush_done
;
227 enum lttng_event_output output
;
228 /* Maximum subbuffer size. */
229 unsigned long max_sb_size
;
232 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
233 * used for the mmap base and offset.
236 unsigned long mmap_len
;
241 /* UID/GID of the user owning the session to which stream belongs */
244 /* Network sequence number. Indicating on which relayd socket it goes. */
245 uint64_t net_seq_idx
;
247 * Indicate if this stream was successfully sent to a relayd. This is set
248 * after the refcount of the relayd is incremented and is checked when the
249 * stream is closed before decrementing the refcount in order to avoid an
252 unsigned int sent_to_relayd
;
254 /* Identify if the stream is the metadata */
255 unsigned int metadata_flag
;
256 /* Used when the stream is set for network streaming */
257 uint64_t relayd_stream_id
;
259 * When sending a stream packet to a relayd, this number is used to track
260 * the packet sent by the consumer and seen by the relayd. When sending the
261 * data header to the relayd, this number is sent and if the transmission
262 * was successful, it is incremented.
264 * Even if the full data is not fully transmitted it won't matter since
265 * only two possible error can happen after that where either the relayd
266 * died or a read error is detected on the stream making this value useless
269 * This value SHOULD be read/updated atomically or with the lock acquired.
271 uint64_t next_net_seq_num
;
273 * Lock to use the stream FDs since they are used between threads.
275 * This is nested INSIDE the consumer_data lock.
276 * This is nested INSIDE the metadata cache lock.
277 * This is nested INSIDE the channel lock.
278 * This is nested INSIDE the channel timer lock.
279 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
281 pthread_mutex_t lock
;
282 /* Tracing session id */
285 * Indicates if the stream end point is still active or not (network
286 * streaming or local file system). The thread "owning" the stream is
287 * handling this status and can be notified of a state change through the
288 * consumer data appropriate pipe.
290 enum consumer_endpoint_status endpoint_status
;
291 /* Stream name. Format is: <channel_name>_<cpu_number> */
292 char name
[LTTNG_SYMBOL_NAME_LEN
];
293 /* Internal state of libustctl. */
294 struct ustctl_consumer_stream
*ustream
;
295 struct cds_list_head send_node
;
296 /* On-disk circular buffer */
297 uint64_t tracefile_size_current
;
298 uint64_t tracefile_count_current
;
300 * Monitor or not the streams of this channel meaning this indicates if the
301 * streams should be sent to the data/metadata thread or added to the no
302 * monitor list of the channel.
304 unsigned int monitor
;
306 * Indicate if the stream is globally visible meaning that it has been
307 * added to the multiple hash tables. If *not* set, NO lock should be
308 * acquired in the destroy path.
310 unsigned int globally_visible
;
312 * Pipe to wake up the metadata poll thread when the UST metadata
315 int ust_metadata_poll_pipe
[2];
317 * How much metadata was read from the metadata cache and sent
320 uint64_t ust_metadata_pushed
;
324 * Internal representation of a relayd socket pair.
326 struct consumer_relayd_sock_pair
{
327 /* Network sequence number. */
328 uint64_t net_seq_idx
;
329 /* Number of stream associated with this relayd */
330 unsigned int refcount
;
333 * This flag indicates whether or not we should destroy this object. The
334 * destruction should ONLY occurs when this flag is set and the refcount is
337 unsigned int destroy_flag
;
340 * Mutex protecting the control socket to avoid out of order packets
341 * between threads sending data to the relayd. Since metadata data is sent
342 * over that socket, at least two sendmsg() are needed (header + data)
343 * creating a race for packets to overlap between threads using it.
345 * This is nested INSIDE the consumer_data lock.
346 * This is nested INSIDE the stream lock.
348 pthread_mutex_t ctrl_sock_mutex
;
350 /* Control socket. Command and metadata are passed over it */
351 struct lttcomm_relayd_sock control_sock
;
354 * We don't need a mutex at this point since we only splice or write single
355 * large chunk of data with a header appended at the begining. Moreover,
356 * this socket is for now only used in a single thread.
358 struct lttcomm_relayd_sock data_sock
;
359 struct lttng_ht_node_u64 node
;
361 /* Session id on both sides for the sockets. */
362 uint64_t relayd_session_id
;
363 uint64_t sessiond_session_id
;
367 * UST consumer local data to the program. One or more instance per
370 struct lttng_consumer_local_data
{
372 * Function to call when data is available on a buffer.
373 * Returns the number of bytes read, or negative error value.
375 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
376 struct lttng_consumer_local_data
*ctx
);
378 * function to call when we receive a new channel, it receives a
379 * newly allocated channel, depending on the return code of this
380 * function, the new channel will be handled by the application
384 * > 0 (success, FD is kept by application)
385 * == 0 (success, FD is left to library)
388 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
390 * function to call when we receive a new stream, it receives a
391 * newly allocated stream, depending on the return code of this
392 * function, the new stream will be handled by the application
396 * > 0 (success, FD is kept by application)
397 * == 0 (success, FD is left to library)
400 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
402 * function to call when a stream is getting updated by the session
403 * daemon, this function receives the sessiond key and the new
404 * state, depending on the return code of this function the
405 * update of state for the stream is handled by the application
409 * > 0 (success, FD is kept by application)
410 * == 0 (success, FD is left to library)
413 int (*on_update_stream
)(uint64_t sessiond_key
, uint32_t state
);
414 enum lttng_consumer_type type
;
415 /* socket to communicate errors with sessiond */
416 int consumer_error_socket
;
417 /* socket to ask metadata to sessiond. */
418 int consumer_metadata_socket
;
420 * Protect consumer_metadata_socket.
422 * This is nested OUTSIDE the metadata cache lock.
424 pthread_mutex_t metadata_socket_lock
;
425 /* socket to exchange commands with sessiond */
426 char *consumer_command_sock_path
;
427 /* communication with splice */
428 int consumer_thread_pipe
[2];
429 int consumer_channel_pipe
[2];
430 int consumer_splice_metadata_pipe
[2];
431 /* Data stream poll thread pipe. To transfer data stream to the thread */
432 struct lttng_pipe
*consumer_data_pipe
;
433 /* to let the signal handler wake up the fd receiver thread */
434 int consumer_should_quit
[2];
435 /* Metadata poll thread pipe. Transfer metadata stream to it */
436 struct lttng_pipe
*consumer_metadata_pipe
;
440 * Library-level data. One instance per process.
442 struct lttng_consumer_global_data
{
444 * At this time, this lock is used to ensure coherence between the count
445 * and number of element in the hash table. It's also a protection for
446 * concurrent read/write between threads.
448 * This is nested OUTSIDE the stream lock.
449 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
451 pthread_mutex_t lock
;
454 * Number of streams in the data stream hash table declared outside.
455 * Protected by consumer_data.lock.
459 /* Channel hash table protected by consumer_data.lock. */
460 struct lttng_ht
*channel_ht
;
462 * Flag specifying if the local array of FDs needs update in the
463 * poll function. Protected by consumer_data.lock.
465 unsigned int need_update
;
466 enum lttng_consumer_type type
;
469 * Relayd socket(s) hashtable indexed by network sequence number. Each
470 * stream has an index which associate the right relayd socket to use.
472 struct lttng_ht
*relayd_ht
;
475 * This hash table contains all streams (metadata and data) indexed by
476 * session id. In other words, the ht is indexed by session id and each
477 * bucket contains the list of associated streams.
479 * This HT uses the "node_session_id" of the consumer stream.
481 struct lttng_ht
*stream_list_ht
;
484 * This HT uses the "node_channel_id" of the consumer stream.
486 struct lttng_ht
*stream_per_chan_id_ht
;
490 * Init consumer data structures.
492 void lttng_consumer_init(void);
495 * Set the error socket for communication with a session daemon.
497 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
501 * Set the command socket path for communication with a session daemon.
503 void lttng_consumer_set_command_sock_path(
504 struct lttng_consumer_local_data
*ctx
, char *sock
);
507 * Send return code to session daemon.
509 * Returns the return code of sendmsg : the number of bytes transmitted or -1
512 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
515 * Called from signal handler to ensure a clean exit.
517 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
520 * Cleanup the daemon's socket on exit.
522 void lttng_consumer_cleanup(void);
525 * Flush pending writes to trace output disk file.
527 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
531 * Poll on the should_quit pipe and the command socket return -1 on error and
532 * should exit, 0 if data is available on the command socket
534 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
536 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
538 enum lttng_consumer_stream_state state
,
539 const char *channel_name
,
546 enum consumer_channel_type type
,
547 unsigned int monitor
);
548 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
550 const char *pathname
,
555 enum lttng_event_output output
,
556 uint64_t tracefile_size
,
557 uint64_t tracefile_count
,
558 uint64_t session_id_per_pid
,
559 unsigned int monitor
);
560 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
561 struct lttng_ht
*ht
);
562 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
563 struct lttng_ht
*ht
);
564 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
565 struct lttng_consumer_local_data
*ctx
);
566 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
568 /* lttng-relayd consumer command */
569 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
570 uint64_t net_seq_idx
);
571 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
572 int consumer_send_relayd_stream(struct lttng_consumer_stream
*stream
, char *path
);
573 void close_relayd_stream(struct lttng_consumer_stream
*stream
);
574 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
575 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
577 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
579 struct lttng_consumer_local_data
*lttng_consumer_create(
580 enum lttng_consumer_type type
,
581 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
582 struct lttng_consumer_local_data
*ctx
),
583 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
584 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
585 int (*update_stream
)(uint64_t sessiond_key
, uint32_t state
));
586 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
587 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
588 struct lttng_consumer_local_data
*ctx
,
589 struct lttng_consumer_stream
*stream
, unsigned long len
,
590 unsigned long padding
);
591 ssize_t
lttng_consumer_on_read_subbuffer_splice(
592 struct lttng_consumer_local_data
*ctx
,
593 struct lttng_consumer_stream
*stream
, unsigned long len
,
594 unsigned long padding
);
595 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
596 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
598 void *consumer_thread_metadata_poll(void *data
);
599 void *consumer_thread_data_poll(void *data
);
600 void *consumer_thread_sessiond_poll(void *data
);
601 void *consumer_thread_channel_poll(void *data
);
602 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
603 int sock
, struct pollfd
*consumer_sockpoll
);
605 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
606 struct lttng_consumer_local_data
*ctx
);
607 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
608 int consumer_add_relayd_socket(uint64_t net_seq_idx
, int sock_type
,
609 struct lttng_consumer_local_data
*ctx
, int sock
,
610 struct pollfd
*consumer_sockpoll
, struct lttcomm_relayd_sock
*relayd_sock
,
611 uint64_t sessiond_id
);
612 void consumer_flag_relayd_for_destroy(
613 struct consumer_relayd_sock_pair
*relayd
);
614 int consumer_data_pending(uint64_t id
);
615 int consumer_send_status_msg(int sock
, int ret_code
);
616 int consumer_send_status_channel(int sock
,
617 struct lttng_consumer_channel
*channel
);
618 void notify_thread_del_channel(struct lttng_consumer_local_data
*ctx
,
620 void consumer_destroy_relayd(struct consumer_relayd_sock_pair
*relayd
);
621 unsigned long consumer_get_consumed_maxsize(unsigned long consumed_pos
,
622 unsigned long produced_pos
, uint64_t max_stream_size
);
623 int consumer_add_data_stream(struct lttng_consumer_stream
*stream
);
624 void consumer_del_stream_for_data(struct lttng_consumer_stream
*stream
);
625 int consumer_add_metadata_stream(struct lttng_consumer_stream
*stream
);
626 void consumer_del_stream_for_metadata(struct lttng_consumer_stream
*stream
);
628 #endif /* LIB_CONSUMER_H */