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 is nested INSIDE the consumer data lock.
176 * This is nested OUTSIDE the metadata cache lock.
177 * This is nested OUTSIDE stream lock.
178 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
180 pthread_mutex_t lock
;
184 * Internal representation of the streams, sessiond_key is used to identify
187 struct lttng_consumer_stream
{
188 /* HT node used by the data_ht and metadata_ht */
189 struct lttng_ht_node_u64 node
;
190 /* stream indexed per channel key node */
191 struct lttng_ht_node_u64 node_channel_id
;
192 /* HT node used in consumer_data.stream_list_ht */
193 struct lttng_ht_node_u64 node_session_id
;
194 /* Pointer to associated channel. */
195 struct lttng_consumer_channel
*chan
;
197 /* Key by which the stream is indexed for 'node'. */
200 * File descriptor of the data output file. This can be either a file or a
201 * socket fd for relayd streaming.
203 int out_fd
; /* output file to write the data */
204 /* Write position in the output file descriptor */
206 enum lttng_consumer_stream_state state
;
209 int hangup_flush_done
;
210 enum lttng_event_output output
;
211 /* Maximum subbuffer size. */
212 unsigned long max_sb_size
;
215 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
216 * used for the mmap base and offset.
219 unsigned long mmap_len
;
224 /* UID/GID of the user owning the session to which stream belongs */
227 /* Network sequence number. Indicating on which relayd socket it goes. */
228 uint64_t net_seq_idx
;
230 * Indicate if this stream was successfully sent to a relayd. This is set
231 * after the refcount of the relayd is incremented and is checked when the
232 * stream is closed before decrementing the refcount in order to avoid an
235 unsigned int sent_to_relayd
;
237 /* Identify if the stream is the metadata */
238 unsigned int metadata_flag
;
239 /* Used when the stream is set for network streaming */
240 uint64_t relayd_stream_id
;
242 * When sending a stream packet to a relayd, this number is used to track
243 * the packet sent by the consumer and seen by the relayd. When sending the
244 * data header to the relayd, this number is sent and if the transmission
245 * was successful, it is incremented.
247 * Even if the full data is not fully transmitted it won't matter since
248 * only two possible error can happen after that where either the relayd
249 * died or a read error is detected on the stream making this value useless
252 * This value SHOULD be read/updated atomically or with the lock acquired.
254 uint64_t next_net_seq_num
;
256 * Lock to use the stream FDs since they are used between threads.
258 * This is nested INSIDE the consumer_data lock.
259 * This is nested INSIDE the metadata cache lock.
260 * This is nested INSIDE the channel lock.
261 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
263 pthread_mutex_t lock
;
264 /* Tracing session id */
267 * Indicates if the stream end point is still active or not (network
268 * streaming or local file system). The thread "owning" the stream is
269 * handling this status and can be notified of a state change through the
270 * consumer data appropriate pipe.
272 enum consumer_endpoint_status endpoint_status
;
273 /* Stream name. Format is: <channel_name>_<cpu_number> */
274 char name
[LTTNG_SYMBOL_NAME_LEN
];
275 /* Internal state of libustctl. */
276 struct ustctl_consumer_stream
*ustream
;
277 struct cds_list_head send_node
;
278 /* On-disk circular buffer */
279 uint64_t tracefile_size_current
;
280 uint64_t tracefile_count_current
;
282 * Monitor or not the streams of this channel meaning this indicates if the
283 * streams should be sent to the data/metadata thread or added to the no
284 * monitor list of the channel.
286 unsigned int monitor
;
288 * Indicate if the stream is globally visible meaning that it has been
289 * added to the multiple hash tables. If *not* set, NO lock should be
290 * acquired in the destroy path.
292 unsigned int globally_visible
;
296 * Internal representation of a relayd socket pair.
298 struct consumer_relayd_sock_pair
{
299 /* Network sequence number. */
300 uint64_t net_seq_idx
;
301 /* Number of stream associated with this relayd */
302 unsigned int refcount
;
305 * This flag indicates whether or not we should destroy this object. The
306 * destruction should ONLY occurs when this flag is set and the refcount is
309 unsigned int destroy_flag
;
312 * Mutex protecting the control socket to avoid out of order packets
313 * between threads sending data to the relayd. Since metadata data is sent
314 * over that socket, at least two sendmsg() are needed (header + data)
315 * creating a race for packets to overlap between threads using it.
317 * This is nested INSIDE the consumer_data lock.
318 * This is nested INSIDE the stream lock.
320 pthread_mutex_t ctrl_sock_mutex
;
322 /* Control socket. Command and metadata are passed over it */
323 struct lttcomm_relayd_sock control_sock
;
326 * We don't need a mutex at this point since we only splice or write single
327 * large chunk of data with a header appended at the begining. Moreover,
328 * this socket is for now only used in a single thread.
330 struct lttcomm_relayd_sock data_sock
;
331 struct lttng_ht_node_u64 node
;
333 /* Session id on both sides for the sockets. */
334 uint64_t relayd_session_id
;
335 uint64_t sessiond_session_id
;
339 * UST consumer local data to the program. One or more instance per
342 struct lttng_consumer_local_data
{
344 * Function to call when data is available on a buffer.
345 * Returns the number of bytes read, or negative error value.
347 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
348 struct lttng_consumer_local_data
*ctx
);
350 * function to call when we receive a new channel, it receives a
351 * newly allocated channel, depending on the return code of this
352 * function, the new channel will be handled by the application
356 * > 0 (success, FD is kept by application)
357 * == 0 (success, FD is left to library)
360 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
362 * function to call when we receive a new stream, it receives a
363 * newly allocated stream, depending on the return code of this
364 * function, the new stream will be handled by the application
368 * > 0 (success, FD is kept by application)
369 * == 0 (success, FD is left to library)
372 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
374 * function to call when a stream is getting updated by the session
375 * daemon, this function receives the sessiond key and the new
376 * state, depending on the return code of this function the
377 * update of state for the stream is handled by the application
381 * > 0 (success, FD is kept by application)
382 * == 0 (success, FD is left to library)
385 int (*on_update_stream
)(uint64_t sessiond_key
, uint32_t state
);
386 enum lttng_consumer_type type
;
387 /* socket to communicate errors with sessiond */
388 int consumer_error_socket
;
389 /* socket to ask metadata to sessiond */
390 int consumer_metadata_socket
;
391 /* socket to exchange commands with sessiond */
392 char *consumer_command_sock_path
;
393 /* communication with splice */
394 int consumer_thread_pipe
[2];
395 int consumer_channel_pipe
[2];
396 int consumer_splice_metadata_pipe
[2];
397 /* Data stream poll thread pipe. To transfer data stream to the thread */
398 struct lttng_pipe
*consumer_data_pipe
;
399 /* to let the signal handler wake up the fd receiver thread */
400 int consumer_should_quit
[2];
401 /* Metadata poll thread pipe. Transfer metadata stream to it */
402 struct lttng_pipe
*consumer_metadata_pipe
;
406 * Library-level data. One instance per process.
408 struct lttng_consumer_global_data
{
410 * At this time, this lock is used to ensure coherence between the count
411 * and number of element in the hash table. It's also a protection for
412 * concurrent read/write between threads.
414 * This is nested OUTSIDE the stream lock.
415 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
417 pthread_mutex_t lock
;
420 * Number of streams in the data stream hash table declared outside.
421 * Protected by consumer_data.lock.
425 /* Channel hash table protected by consumer_data.lock. */
426 struct lttng_ht
*channel_ht
;
428 * Flag specifying if the local array of FDs needs update in the
429 * poll function. Protected by consumer_data.lock.
431 unsigned int need_update
;
432 enum lttng_consumer_type type
;
435 * Relayd socket(s) hashtable indexed by network sequence number. Each
436 * stream has an index which associate the right relayd socket to use.
438 struct lttng_ht
*relayd_ht
;
441 * This hash table contains all streams (metadata and data) indexed by
442 * session id. In other words, the ht is indexed by session id and each
443 * bucket contains the list of associated streams.
445 * This HT uses the "node_session_id" of the consumer stream.
447 struct lttng_ht
*stream_list_ht
;
450 * This HT uses the "node_channel_id" of the consumer stream.
452 struct lttng_ht
*stream_per_chan_id_ht
;
456 * Init consumer data structures.
458 void lttng_consumer_init(void);
461 * Set the error socket for communication with a session daemon.
463 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
467 * Set the command socket path for communication with a session daemon.
469 void lttng_consumer_set_command_sock_path(
470 struct lttng_consumer_local_data
*ctx
, char *sock
);
473 * Send return code to session daemon.
475 * Returns the return code of sendmsg : the number of bytes transmitted or -1
478 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
481 * Called from signal handler to ensure a clean exit.
483 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
486 * Cleanup the daemon's socket on exit.
488 void lttng_consumer_cleanup(void);
491 * Flush pending writes to trace output disk file.
493 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
497 * Poll on the should_quit pipe and the command socket return -1 on error and
498 * should exit, 0 if data is available on the command socket
500 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
502 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
504 enum lttng_consumer_stream_state state
,
505 const char *channel_name
,
512 enum consumer_channel_type type
,
513 unsigned int monitor
);
514 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
516 const char *pathname
,
521 enum lttng_event_output output
,
522 uint64_t tracefile_size
,
523 uint64_t tracefile_count
,
524 uint64_t session_id_per_pid
,
525 unsigned int monitor
);
526 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
527 struct lttng_ht
*ht
);
528 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
529 struct lttng_ht
*ht
);
530 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
531 struct lttng_consumer_local_data
*ctx
);
532 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
534 /* lttng-relayd consumer command */
535 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
536 uint64_t net_seq_idx
);
537 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
538 int consumer_send_relayd_stream(struct lttng_consumer_stream
*stream
, char *path
);
539 void close_relayd_stream(struct lttng_consumer_stream
*stream
);
540 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
541 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
543 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
545 struct lttng_consumer_local_data
*lttng_consumer_create(
546 enum lttng_consumer_type type
,
547 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
548 struct lttng_consumer_local_data
*ctx
),
549 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
550 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
551 int (*update_stream
)(uint64_t sessiond_key
, uint32_t state
));
552 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
553 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
554 struct lttng_consumer_local_data
*ctx
,
555 struct lttng_consumer_stream
*stream
, unsigned long len
,
556 unsigned long padding
);
557 ssize_t
lttng_consumer_on_read_subbuffer_splice(
558 struct lttng_consumer_local_data
*ctx
,
559 struct lttng_consumer_stream
*stream
, unsigned long len
,
560 unsigned long padding
);
561 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
562 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
564 void *consumer_thread_metadata_poll(void *data
);
565 void *consumer_thread_data_poll(void *data
);
566 void *consumer_thread_sessiond_poll(void *data
);
567 void *consumer_thread_channel_poll(void *data
);
568 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
569 int sock
, struct pollfd
*consumer_sockpoll
);
571 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
572 struct lttng_consumer_local_data
*ctx
);
573 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
574 int consumer_add_relayd_socket(uint64_t net_seq_idx
, int sock_type
,
575 struct lttng_consumer_local_data
*ctx
, int sock
,
576 struct pollfd
*consumer_sockpoll
, struct lttcomm_relayd_sock
*relayd_sock
,
577 uint64_t sessiond_id
);
578 void consumer_flag_relayd_for_destroy(
579 struct consumer_relayd_sock_pair
*relayd
);
580 int consumer_data_pending(uint64_t id
);
581 int consumer_send_status_msg(int sock
, int ret_code
);
582 int consumer_send_status_channel(int sock
,
583 struct lttng_consumer_channel
*channel
);
584 void notify_thread_del_channel(struct lttng_consumer_local_data
*ctx
,
586 void consumer_destroy_relayd(struct consumer_relayd_sock_pair
*relayd
);
587 unsigned long consumer_get_consumed_maxsize(unsigned long consumed_pos
,
588 unsigned long produced_pos
, uint64_t max_stream_size
);
590 #endif /* LIB_CONSUMER_H */