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>
35 /* Commands for consumer */
36 enum lttng_consumer_command
{
37 LTTNG_CONSUMER_ADD_CHANNEL
,
38 LTTNG_CONSUMER_ADD_STREAM
,
39 /* pause, delete, active depending on fd state */
40 LTTNG_CONSUMER_UPDATE_STREAM
,
41 /* inform the consumer to quit when all fd has hang up */
43 LTTNG_CONSUMER_ADD_RELAYD_SOCKET
,
44 /* Inform the consumer to kill a specific relayd connection */
45 LTTNG_CONSUMER_DESTROY_RELAYD
,
46 /* Return to the sessiond if there is data pending for a session */
47 LTTNG_CONSUMER_DATA_PENDING
,
48 /* Consumer creates a channel and returns it to sessiond. */
49 LTTNG_CONSUMER_ASK_CHANNEL_CREATION
,
50 LTTNG_CONSUMER_GET_CHANNEL
,
51 LTTNG_CONSUMER_DESTROY_CHANNEL
,
52 LTTNG_CONSUMER_PUSH_METADATA
,
53 LTTNG_CONSUMER_CLOSE_METADATA
,
54 LTTNG_CONSUMER_SETUP_METADATA
,
55 LTTNG_CONSUMER_FLUSH_CHANNEL
,
58 /* State of each fd in consumer */
59 enum lttng_consumer_stream_state
{
60 LTTNG_CONSUMER_ACTIVE_STREAM
,
61 LTTNG_CONSUMER_PAUSE_STREAM
,
62 LTTNG_CONSUMER_DELETE_STREAM
,
65 enum lttng_consumer_type
{
66 LTTNG_CONSUMER_UNKNOWN
= 0,
67 LTTNG_CONSUMER_KERNEL
,
72 enum consumer_endpoint_status
{
73 CONSUMER_ENDPOINT_ACTIVE
,
74 CONSUMER_ENDPOINT_INACTIVE
,
77 enum consumer_channel_output
{
78 CONSUMER_CHANNEL_MMAP
= 0,
79 CONSUMER_CHANNEL_SPLICE
= 1,
82 enum consumer_channel_type
{
83 CONSUMER_CHANNEL_TYPE_METADATA
= 0,
84 CONSUMER_CHANNEL_TYPE_DATA
= 1,
88 struct cds_list_head head
;
93 struct consumer_metadata_cache
;
95 struct lttng_consumer_channel
{
96 /* HT node used for consumer_data.channel_ht */
97 struct lttng_ht_node_u64 node
;
98 /* Indexed key. Incremented value in the consumer. */
100 /* Number of streams referencing this channel */
102 /* Tracing session id on the session daemon side. */
104 /* Channel trace file path name. */
105 char pathname
[PATH_MAX
];
107 char name
[LTTNG_SYMBOL_NAME_LEN
];
108 /* UID and GID of the channel. */
111 /* Relayd id of the channel. -1 if it does not apply. */
114 * Number of streams NOT initialized yet. This is used in order to not
115 * delete this channel if streams are getting initialized.
117 unsigned int nb_init_stream_left
;
118 /* Output type (mmap or splice). */
119 enum consumer_channel_output output
;
120 /* Channel type for stream */
121 enum consumer_channel_type type
;
124 struct ustctl_consumer_channel
*uchan
;
125 unsigned char uuid
[UUID_STR_LEN
];
127 * Temporary stream list used to store the streams once created and waiting
128 * to be sent to the session daemon by receiving the
129 * LTTNG_CONSUMER_GET_CHANNEL.
131 struct stream_list streams
;
133 * Set if the channel is metadata. We keep a reference to the stream
134 * because we have to flush data once pushed by the session daemon. For a
135 * regular channel, this is always set to NULL.
137 struct lttng_consumer_stream
*metadata_stream
;
141 /* Node within channel thread ht */
142 struct lttng_ht_node_u64 wait_fd_node
;
144 /* Metadata cache is metadata channel */
145 struct consumer_metadata_cache
*metadata_cache
;
146 /* For metadata periodical flush */
147 int switch_timer_enabled
;
148 timer_t switch_timer
;
149 /* On-disk circular buffer */
150 uint64_t tracefile_size
;
151 uint64_t tracefile_count
;
155 * Internal representation of the streams, sessiond_key is used to identify
158 struct lttng_consumer_stream
{
159 /* HT node used by the data_ht and metadata_ht */
160 struct lttng_ht_node_u64 node
;
161 /* stream indexed per channel key node */
162 struct lttng_ht_node_u64 node_channel_id
;
163 /* HT node used in consumer_data.stream_list_ht */
164 struct lttng_ht_node_u64 node_session_id
;
165 /* Pointer to associated channel. */
166 struct lttng_consumer_channel
*chan
;
168 /* Key by which the stream is indexed for 'node'. */
171 * File descriptor of the data output file. This can be either a file or a
172 * socket fd for relayd streaming.
174 int out_fd
; /* output file to write the data */
175 /* Write position in the output file descriptor */
177 enum lttng_consumer_stream_state state
;
180 int hangup_flush_done
;
181 enum lttng_event_output output
;
182 /* Maximum subbuffer size. */
183 unsigned long max_sb_size
;
186 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
187 * used for the mmap base and offset.
190 unsigned long mmap_len
;
195 /* UID/GID of the user owning the session to which stream belongs */
198 /* Network sequence number. Indicating on which relayd socket it goes. */
199 uint64_t net_seq_idx
;
200 /* Identify if the stream is the metadata */
201 unsigned int metadata_flag
;
202 /* Used when the stream is set for network streaming */
203 uint64_t relayd_stream_id
;
205 * When sending a stream packet to a relayd, this number is used to track
206 * the packet sent by the consumer and seen by the relayd. When sending the
207 * data header to the relayd, this number is sent and if the transmission
208 * was successful, it is incremented.
210 * Even if the full data is not fully transmitted it won't matter since
211 * only two possible error can happen after that where either the relayd
212 * died or a read error is detected on the stream making this value useless
215 * This value SHOULD be read/updated atomically or with the lock acquired.
217 uint64_t next_net_seq_num
;
219 * Lock to use the stream FDs since they are used between threads.
221 * This is nested INSIDE the consumer_data lock.
222 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
224 pthread_mutex_t lock
;
225 /* Tracing session id */
228 * Indicates if the stream end point is still active or not (network
229 * streaming or local file system). The thread "owning" the stream is
230 * handling this status and can be notified of a state change through the
231 * consumer data appropriate pipe.
233 enum consumer_endpoint_status endpoint_status
;
234 /* Stream name. Format is: <channel_name>_<cpu_number> */
235 char name
[LTTNG_SYMBOL_NAME_LEN
];
236 /* Internal state of libustctl. */
237 struct ustctl_consumer_stream
*ustream
;
238 struct cds_list_head send_node
;
239 /* On-disk circular buffer */
240 uint64_t tracefile_size_current
;
241 uint64_t tracefile_count_current
;
245 * Internal representation of a relayd socket pair.
247 struct consumer_relayd_sock_pair
{
248 /* Network sequence number. */
250 /* Number of stream associated with this relayd */
251 unsigned int refcount
;
254 * This flag indicates whether or not we should destroy this object. The
255 * destruction should ONLY occurs when this flag is set and the refcount is
258 unsigned int destroy_flag
;
261 * Mutex protecting the control socket to avoid out of order packets
262 * between threads sending data to the relayd. Since metadata data is sent
263 * over that socket, at least two sendmsg() are needed (header + data)
264 * creating a race for packets to overlap between threads using it.
266 * This is nested INSIDE the consumer_data lock.
267 * This is nested INSIDE the stream lock.
269 pthread_mutex_t ctrl_sock_mutex
;
271 /* Control socket. Command and metadata are passed over it */
272 struct lttcomm_sock control_sock
;
275 * We don't need a mutex at this point since we only splice or write single
276 * large chunk of data with a header appended at the begining. Moreover,
277 * this socket is for now only used in a single thread.
279 struct lttcomm_sock data_sock
;
280 struct lttng_ht_node_u64 node
;
282 /* Session id on both sides for the sockets. */
283 uint64_t relayd_session_id
;
284 uint64_t sessiond_session_id
;
288 * UST consumer local data to the program. One or more instance per
291 struct lttng_consumer_local_data
{
293 * Function to call when data is available on a buffer.
294 * Returns the number of bytes read, or negative error value.
296 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
297 struct lttng_consumer_local_data
*ctx
);
299 * function to call when we receive a new channel, it receives a
300 * newly allocated channel, depending on the return code of this
301 * function, the new channel will be handled by the application
305 * > 0 (success, FD is kept by application)
306 * == 0 (success, FD is left to library)
309 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
311 * function to call when we receive a new stream, it receives a
312 * newly allocated stream, depending on the return code of this
313 * function, the new stream will be handled by the application
317 * > 0 (success, FD is kept by application)
318 * == 0 (success, FD is left to library)
321 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
323 * function to call when a stream is getting updated by the session
324 * daemon, this function receives the sessiond key and the new
325 * state, depending on the return code of this function the
326 * update of state for the stream is handled by the application
330 * > 0 (success, FD is kept by application)
331 * == 0 (success, FD is left to library)
334 int (*on_update_stream
)(int sessiond_key
, uint32_t state
);
335 enum lttng_consumer_type type
;
336 /* socket to communicate errors with sessiond */
337 int consumer_error_socket
;
338 /* socket to ask metadata to sessiond */
339 int consumer_metadata_socket
;
340 /* socket to exchange commands with sessiond */
341 char *consumer_command_sock_path
;
342 /* communication with splice */
343 int consumer_thread_pipe
[2];
344 int consumer_channel_pipe
[2];
345 int consumer_splice_metadata_pipe
[2];
346 /* Data stream poll thread pipe. To transfer data stream to the thread */
347 int consumer_data_pipe
[2];
348 /* to let the signal handler wake up the fd receiver thread */
349 int consumer_should_quit
[2];
350 /* Metadata poll thread pipe. Transfer metadata stream to it */
351 int consumer_metadata_pipe
[2];
355 * Library-level data. One instance per process.
357 struct lttng_consumer_global_data
{
359 * At this time, this lock is used to ensure coherence between the count
360 * and number of element in the hash table. It's also a protection for
361 * concurrent read/write between threads.
363 * This is nested OUTSIDE the stream lock.
364 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
366 pthread_mutex_t lock
;
369 * Number of streams in the data stream hash table declared outside.
370 * Protected by consumer_data.lock.
374 /* Channel hash table protected by consumer_data.lock. */
375 struct lttng_ht
*channel_ht
;
377 * Flag specifying if the local array of FDs needs update in the
378 * poll function. Protected by consumer_data.lock.
380 unsigned int need_update
;
381 enum lttng_consumer_type type
;
384 * Relayd socket(s) hashtable indexed by network sequence number. Each
385 * stream has an index which associate the right relayd socket to use.
387 struct lttng_ht
*relayd_ht
;
390 * This hash table contains all streams (metadata and data) indexed by
391 * session id. In other words, the ht is indexed by session id and each
392 * bucket contains the list of associated streams.
394 * This HT uses the "node_session_id" of the consumer stream.
396 struct lttng_ht
*stream_list_ht
;
399 * This HT uses the "node_channel_id" of the consumer stream.
401 struct lttng_ht
*stream_per_chan_id_ht
;
405 * Init consumer data structures.
407 void lttng_consumer_init(void);
410 * Set the error socket for communication with a session daemon.
412 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
416 * Set the command socket path for communication with a session daemon.
418 void lttng_consumer_set_command_sock_path(
419 struct lttng_consumer_local_data
*ctx
, char *sock
);
422 * Send return code to session daemon.
424 * Returns the return code of sendmsg : the number of bytes transmitted or -1
427 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
430 * Called from signal handler to ensure a clean exit.
432 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
435 * Cleanup the daemon's socket on exit.
437 void lttng_consumer_cleanup(void);
440 * Flush pending writes to trace output disk file.
442 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
446 * Poll on the should_quit pipe and the command socket return -1 on error and
447 * should exit, 0 if data is available on the command socket
449 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
451 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
453 enum lttng_consumer_stream_state state
,
454 const char *channel_name
,
461 enum consumer_channel_type type
);
462 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
464 const char *pathname
,
469 enum lttng_event_output output
,
470 uint64_t tracefile_size
,
471 uint64_t tracefile_count
);
472 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
473 struct lttng_ht
*ht
);
474 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
475 struct lttng_ht
*ht
);
476 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
477 struct lttng_consumer_local_data
*ctx
);
478 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
480 /* lttng-relayd consumer command */
481 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
483 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
484 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
485 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
487 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
489 struct lttng_consumer_local_data
*lttng_consumer_create(
490 enum lttng_consumer_type type
,
491 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
492 struct lttng_consumer_local_data
*ctx
),
493 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
494 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
495 int (*update_stream
)(int sessiond_key
, uint32_t state
));
496 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
497 int lttng_create_output_file(struct lttng_consumer_stream
*stream
);
498 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
499 struct lttng_consumer_local_data
*ctx
,
500 struct lttng_consumer_stream
*stream
, unsigned long len
,
501 unsigned long padding
);
502 ssize_t
lttng_consumer_on_read_subbuffer_splice(
503 struct lttng_consumer_local_data
*ctx
,
504 struct lttng_consumer_stream
*stream
, unsigned long len
,
505 unsigned long padding
);
506 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
507 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
509 void *consumer_thread_metadata_poll(void *data
);
510 void *consumer_thread_data_poll(void *data
);
511 void *consumer_thread_sessiond_poll(void *data
);
512 void *consumer_thread_channel_poll(void *data
);
513 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
514 int sock
, struct pollfd
*consumer_sockpoll
);
516 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
517 struct lttng_consumer_local_data
*ctx
);
518 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
519 int consumer_add_relayd_socket(int net_seq_idx
, int sock_type
,
520 struct lttng_consumer_local_data
*ctx
, int sock
,
521 struct pollfd
*consumer_sockpoll
, struct lttcomm_sock
*relayd_sock
,
522 unsigned int sessiond_id
);
523 void consumer_flag_relayd_for_destroy(
524 struct consumer_relayd_sock_pair
*relayd
);
525 int consumer_data_pending(uint64_t id
);
526 int consumer_send_status_msg(int sock
, int ret_code
);
527 int consumer_send_status_channel(int sock
,
528 struct lttng_consumer_channel
*channel
);
530 #endif /* LIB_CONSUMER_H */