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
,
59 /* State of each fd in consumer */
60 enum lttng_consumer_stream_state
{
61 LTTNG_CONSUMER_ACTIVE_STREAM
,
62 LTTNG_CONSUMER_PAUSE_STREAM
,
63 LTTNG_CONSUMER_DELETE_STREAM
,
66 enum lttng_consumer_type
{
67 LTTNG_CONSUMER_UNKNOWN
= 0,
68 LTTNG_CONSUMER_KERNEL
,
73 enum consumer_endpoint_status
{
74 CONSUMER_ENDPOINT_ACTIVE
,
75 CONSUMER_ENDPOINT_INACTIVE
,
78 enum consumer_channel_output
{
79 CONSUMER_CHANNEL_MMAP
= 0,
80 CONSUMER_CHANNEL_SPLICE
= 1,
83 enum consumer_channel_type
{
84 CONSUMER_CHANNEL_TYPE_METADATA
= 0,
85 CONSUMER_CHANNEL_TYPE_DATA
= 1,
89 struct cds_list_head head
;
94 struct consumer_metadata_cache
;
96 struct lttng_consumer_channel
{
97 /* HT node used for consumer_data.channel_ht */
98 struct lttng_ht_node_u64 node
;
99 /* Indexed key. Incremented value in the consumer. */
101 /* Number of streams referencing this channel */
103 /* Tracing session id on the session daemon side. */
105 /* Channel trace file path name. */
106 char pathname
[PATH_MAX
];
108 char name
[LTTNG_SYMBOL_NAME_LEN
];
109 /* UID and GID of the channel. */
112 /* Relayd id of the channel. -1 if it does not apply. */
115 * Number of streams NOT initialized yet. This is used in order to not
116 * delete this channel if streams are getting initialized.
118 unsigned int nb_init_stream_left
;
119 /* Output type (mmap or splice). */
120 enum consumer_channel_output output
;
121 /* Channel type for stream */
122 enum consumer_channel_type type
;
125 struct ustctl_consumer_channel
*uchan
;
126 unsigned char uuid
[UUID_STR_LEN
];
128 * Temporary stream list used to store the streams once created and waiting
129 * to be sent to the session daemon by receiving the
130 * LTTNG_CONSUMER_GET_CHANNEL.
132 struct stream_list streams
;
134 * Set if the channel is metadata. We keep a reference to the stream
135 * because we have to flush data once pushed by the session daemon. For a
136 * regular channel, this is always set to NULL.
138 struct lttng_consumer_stream
*metadata_stream
;
142 /* Node within channel thread ht */
143 struct lttng_ht_node_u64 wait_fd_node
;
145 /* Metadata cache is metadata channel */
146 struct consumer_metadata_cache
*metadata_cache
;
147 /* For metadata periodical flush */
148 int switch_timer_enabled
;
149 timer_t switch_timer
;
150 int switch_timer_error
;
152 /* On-disk circular buffer */
153 uint64_t tracefile_size
;
154 uint64_t tracefile_count
;
158 * Internal representation of the streams, sessiond_key is used to identify
161 struct lttng_consumer_stream
{
162 /* HT node used by the data_ht and metadata_ht */
163 struct lttng_ht_node_u64 node
;
164 /* stream indexed per channel key node */
165 struct lttng_ht_node_u64 node_channel_id
;
166 /* HT node used in consumer_data.stream_list_ht */
167 struct lttng_ht_node_u64 node_session_id
;
168 /* Pointer to associated channel. */
169 struct lttng_consumer_channel
*chan
;
171 /* Key by which the stream is indexed for 'node'. */
174 * File descriptor of the data output file. This can be either a file or a
175 * socket fd for relayd streaming.
177 int out_fd
; /* output file to write the data */
178 /* Write position in the output file descriptor */
180 enum lttng_consumer_stream_state state
;
183 int hangup_flush_done
;
184 enum lttng_event_output output
;
185 /* Maximum subbuffer size. */
186 unsigned long max_sb_size
;
189 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
190 * used for the mmap base and offset.
193 unsigned long mmap_len
;
198 /* UID/GID of the user owning the session to which stream belongs */
201 /* Network sequence number. Indicating on which relayd socket it goes. */
202 uint64_t net_seq_idx
;
203 /* Identify if the stream is the metadata */
204 unsigned int metadata_flag
;
205 /* Used when the stream is set for network streaming */
206 uint64_t relayd_stream_id
;
208 * When sending a stream packet to a relayd, this number is used to track
209 * the packet sent by the consumer and seen by the relayd. When sending the
210 * data header to the relayd, this number is sent and if the transmission
211 * was successful, it is incremented.
213 * Even if the full data is not fully transmitted it won't matter since
214 * only two possible error can happen after that where either the relayd
215 * died or a read error is detected on the stream making this value useless
218 * This value SHOULD be read/updated atomically or with the lock acquired.
220 uint64_t next_net_seq_num
;
222 * Lock to use the stream FDs since they are used between threads.
224 * This is nested INSIDE the consumer_data lock.
225 * This is nested INSIDE the metadata cache lock.
226 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
228 pthread_mutex_t lock
;
229 /* Tracing session id */
232 * Indicates if the stream end point is still active or not (network
233 * streaming or local file system). The thread "owning" the stream is
234 * handling this status and can be notified of a state change through the
235 * consumer data appropriate pipe.
237 enum consumer_endpoint_status endpoint_status
;
238 /* Stream name. Format is: <channel_name>_<cpu_number> */
239 char name
[LTTNG_SYMBOL_NAME_LEN
];
240 /* Internal state of libustctl. */
241 struct ustctl_consumer_stream
*ustream
;
242 struct cds_list_head send_node
;
243 /* On-disk circular buffer */
244 uint64_t tracefile_size_current
;
245 uint64_t tracefile_count_current
;
249 * Internal representation of a relayd socket pair.
251 struct consumer_relayd_sock_pair
{
252 /* Network sequence number. */
254 /* Number of stream associated with this relayd */
255 unsigned int refcount
;
258 * This flag indicates whether or not we should destroy this object. The
259 * destruction should ONLY occurs when this flag is set and the refcount is
262 unsigned int destroy_flag
;
265 * Mutex protecting the control socket to avoid out of order packets
266 * between threads sending data to the relayd. Since metadata data is sent
267 * over that socket, at least two sendmsg() are needed (header + data)
268 * creating a race for packets to overlap between threads using it.
270 * This is nested INSIDE the consumer_data lock.
271 * This is nested INSIDE the stream lock.
273 pthread_mutex_t ctrl_sock_mutex
;
275 /* Control socket. Command and metadata are passed over it */
276 struct lttcomm_relayd_sock control_sock
;
279 * We don't need a mutex at this point since we only splice or write single
280 * large chunk of data with a header appended at the begining. Moreover,
281 * this socket is for now only used in a single thread.
283 struct lttcomm_relayd_sock data_sock
;
284 struct lttng_ht_node_u64 node
;
286 /* Session id on both sides for the sockets. */
287 uint64_t relayd_session_id
;
288 uint64_t sessiond_session_id
;
292 * UST consumer local data to the program. One or more instance per
295 struct lttng_consumer_local_data
{
297 * Function to call when data is available on a buffer.
298 * Returns the number of bytes read, or negative error value.
300 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
301 struct lttng_consumer_local_data
*ctx
);
303 * function to call when we receive a new channel, it receives a
304 * newly allocated channel, depending on the return code of this
305 * function, the new channel will be handled by the application
309 * > 0 (success, FD is kept by application)
310 * == 0 (success, FD is left to library)
313 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
315 * function to call when we receive a new stream, it receives a
316 * newly allocated stream, depending on the return code of this
317 * function, the new stream will be handled by the application
321 * > 0 (success, FD is kept by application)
322 * == 0 (success, FD is left to library)
325 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
327 * function to call when a stream is getting updated by the session
328 * daemon, this function receives the sessiond key and the new
329 * state, depending on the return code of this function the
330 * update of state for the stream is handled by the application
334 * > 0 (success, FD is kept by application)
335 * == 0 (success, FD is left to library)
338 int (*on_update_stream
)(int sessiond_key
, uint32_t state
);
339 enum lttng_consumer_type type
;
340 /* socket to communicate errors with sessiond */
341 int consumer_error_socket
;
342 /* socket to ask metadata to sessiond */
343 int consumer_metadata_socket
;
344 /* socket to exchange commands with sessiond */
345 char *consumer_command_sock_path
;
346 /* communication with splice */
347 int consumer_thread_pipe
[2];
348 int consumer_channel_pipe
[2];
349 int consumer_splice_metadata_pipe
[2];
350 /* Data stream poll thread pipe. To transfer data stream to the thread */
351 struct lttng_pipe
*consumer_data_pipe
;
352 /* to let the signal handler wake up the fd receiver thread */
353 int consumer_should_quit
[2];
354 /* Metadata poll thread pipe. Transfer metadata stream to it */
355 struct lttng_pipe
*consumer_metadata_pipe
;
359 * Library-level data. One instance per process.
361 struct lttng_consumer_global_data
{
363 * At this time, this lock is used to ensure coherence between the count
364 * and number of element in the hash table. It's also a protection for
365 * concurrent read/write between threads.
367 * This is nested OUTSIDE the stream lock.
368 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
370 pthread_mutex_t lock
;
373 * Number of streams in the data stream hash table declared outside.
374 * Protected by consumer_data.lock.
378 /* Channel hash table protected by consumer_data.lock. */
379 struct lttng_ht
*channel_ht
;
381 * Flag specifying if the local array of FDs needs update in the
382 * poll function. Protected by consumer_data.lock.
384 unsigned int need_update
;
385 enum lttng_consumer_type type
;
388 * Relayd socket(s) hashtable indexed by network sequence number. Each
389 * stream has an index which associate the right relayd socket to use.
391 struct lttng_ht
*relayd_ht
;
394 * This hash table contains all streams (metadata and data) indexed by
395 * session id. In other words, the ht is indexed by session id and each
396 * bucket contains the list of associated streams.
398 * This HT uses the "node_session_id" of the consumer stream.
400 struct lttng_ht
*stream_list_ht
;
403 * This HT uses the "node_channel_id" of the consumer stream.
405 struct lttng_ht
*stream_per_chan_id_ht
;
409 * Init consumer data structures.
411 void lttng_consumer_init(void);
414 * Set the error socket for communication with a session daemon.
416 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
420 * Set the command socket path for communication with a session daemon.
422 void lttng_consumer_set_command_sock_path(
423 struct lttng_consumer_local_data
*ctx
, char *sock
);
426 * Send return code to session daemon.
428 * Returns the return code of sendmsg : the number of bytes transmitted or -1
431 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
434 * Called from signal handler to ensure a clean exit.
436 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
439 * Cleanup the daemon's socket on exit.
441 void lttng_consumer_cleanup(void);
444 * Flush pending writes to trace output disk file.
446 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
450 * Poll on the should_quit pipe and the command socket return -1 on error and
451 * should exit, 0 if data is available on the command socket
453 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
455 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
457 enum lttng_consumer_stream_state state
,
458 const char *channel_name
,
465 enum consumer_channel_type type
);
466 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
468 const char *pathname
,
473 enum lttng_event_output output
,
474 uint64_t tracefile_size
,
475 uint64_t tracefile_count
);
476 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
477 struct lttng_ht
*ht
);
478 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
479 struct lttng_ht
*ht
);
480 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
481 struct lttng_consumer_local_data
*ctx
);
482 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
484 /* lttng-relayd consumer command */
485 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
487 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
488 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
489 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
491 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
493 struct lttng_consumer_local_data
*lttng_consumer_create(
494 enum lttng_consumer_type type
,
495 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
496 struct lttng_consumer_local_data
*ctx
),
497 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
498 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
499 int (*update_stream
)(int sessiond_key
, uint32_t state
));
500 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
501 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
502 struct lttng_consumer_local_data
*ctx
,
503 struct lttng_consumer_stream
*stream
, unsigned long len
,
504 unsigned long padding
);
505 ssize_t
lttng_consumer_on_read_subbuffer_splice(
506 struct lttng_consumer_local_data
*ctx
,
507 struct lttng_consumer_stream
*stream
, unsigned long len
,
508 unsigned long padding
);
509 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
510 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
512 void *consumer_thread_metadata_poll(void *data
);
513 void *consumer_thread_data_poll(void *data
);
514 void *consumer_thread_sessiond_poll(void *data
);
515 void *consumer_thread_channel_poll(void *data
);
516 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
517 int sock
, struct pollfd
*consumer_sockpoll
);
519 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
520 struct lttng_consumer_local_data
*ctx
);
521 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
522 int consumer_add_relayd_socket(int net_seq_idx
, int sock_type
,
523 struct lttng_consumer_local_data
*ctx
, int sock
,
524 struct pollfd
*consumer_sockpoll
, struct lttcomm_relayd_sock
*relayd_sock
,
525 unsigned int sessiond_id
);
526 void consumer_flag_relayd_for_destroy(
527 struct consumer_relayd_sock_pair
*relayd
);
528 int consumer_data_pending(uint64_t id
);
529 int consumer_send_status_msg(int sock
, int ret_code
);
530 int consumer_send_status_channel(int sock
,
531 struct lttng_consumer_channel
*channel
);
532 void notify_thread_del_channel(struct lttng_consumer_local_data
*ctx
,
535 #endif /* LIB_CONSUMER_H */