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
;
92 struct lttng_consumer_channel
{
93 /* HT node used for consumer_data.channel_ht */
94 struct lttng_ht_node_u64 node
;
95 /* Indexed key. Incremented value in the consumer. */
97 /* Number of streams referencing this channel */
99 /* Tracing session id on the session daemon side. */
101 /* Channel trace file path name. */
102 char pathname
[PATH_MAX
];
104 char name
[LTTNG_SYMBOL_NAME_LEN
];
105 /* UID and GID of the channel. */
108 /* Relayd id of the channel. -1 if it does not apply. */
111 * Number of streams NOT initialized yet. This is used in order to not
112 * delete this channel if streams are getting initialized.
114 unsigned int nb_init_stream_left
;
115 /* Output type (mmap or splice). */
116 enum consumer_channel_output output
;
117 /* Channel type for stream */
118 enum consumer_channel_type type
;
121 struct ustctl_consumer_channel
*uchan
;
122 unsigned char uuid
[UUID_STR_LEN
];
124 * Temporary stream list used to store the streams once created and waiting
125 * to be sent to the session daemon by receiving the
126 * LTTNG_CONSUMER_GET_CHANNEL.
128 struct stream_list streams
;
130 * Set if the channel is metadata. We keep a reference to the stream
131 * because we have to flush data once pushed by the session daemon. For a
132 * regular channel, this is always set to NULL.
134 struct lttng_consumer_stream
*metadata_stream
;
136 * Metadata written so far. Helps keeping track of
137 * contiguousness and order.
139 uint64_t contig_metadata_written
;
143 /* Node within channel thread ht */
144 struct lttng_ht_node_u64 wait_fd_node
;
148 * Internal representation of the streams, sessiond_key is used to identify
151 struct lttng_consumer_stream
{
152 /* HT node used by the data_ht and metadata_ht */
153 struct lttng_ht_node_u64 node
;
154 /* stream indexed per channel key node */
155 struct lttng_ht_node_u64 node_channel_id
;
156 /* HT node used in consumer_data.stream_list_ht */
157 struct lttng_ht_node_u64 node_session_id
;
158 /* Pointer to associated channel. */
159 struct lttng_consumer_channel
*chan
;
161 /* Key by which the stream is indexed for 'node'. */
164 * File descriptor of the data output file. This can be either a file or a
165 * socket fd for relayd streaming.
167 int out_fd
; /* output file to write the data */
168 /* Write position in the output file descriptor */
170 enum lttng_consumer_stream_state state
;
173 int hangup_flush_done
;
174 enum lttng_event_output output
;
175 /* Maximum subbuffer size. */
176 unsigned long max_sb_size
;
179 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
180 * used for the mmap base and offset.
183 unsigned long mmap_len
;
188 /* UID/GID of the user owning the session to which stream belongs */
191 /* Network sequence number. Indicating on which relayd socket it goes. */
192 uint64_t net_seq_idx
;
193 /* Identify if the stream is the metadata */
194 unsigned int metadata_flag
;
195 /* Used when the stream is set for network streaming */
196 uint64_t relayd_stream_id
;
198 * When sending a stream packet to a relayd, this number is used to track
199 * the packet sent by the consumer and seen by the relayd. When sending the
200 * data header to the relayd, this number is sent and if the transmission
201 * was successful, it is incremented.
203 * Even if the full data is not fully transmitted it won't matter since
204 * only two possible error can happen after that where either the relayd
205 * died or a read error is detected on the stream making this value useless
208 * This value SHOULD be read/updated atomically or with the lock acquired.
210 uint64_t next_net_seq_num
;
212 * Lock to use the stream FDs since they are used between threads.
214 * This is nested INSIDE the consumer_data lock.
215 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
217 pthread_mutex_t lock
;
218 /* Tracing session id */
221 * Indicates if the stream end point is still active or not (network
222 * streaming or local file system). The thread "owning" the stream is
223 * handling this status and can be notified of a state change through the
224 * consumer data appropriate pipe.
226 enum consumer_endpoint_status endpoint_status
;
227 /* Stream name. Format is: <channel_name>_<cpu_number> */
228 char name
[LTTNG_SYMBOL_NAME_LEN
];
229 /* Internal state of libustctl. */
230 struct ustctl_consumer_stream
*ustream
;
231 struct cds_list_head send_node
;
235 * Internal representation of a relayd socket pair.
237 struct consumer_relayd_sock_pair
{
238 /* Network sequence number. */
240 /* Number of stream associated with this relayd */
241 unsigned int refcount
;
244 * This flag indicates whether or not we should destroy this object. The
245 * destruction should ONLY occurs when this flag is set and the refcount is
248 unsigned int destroy_flag
;
251 * Mutex protecting the control socket to avoid out of order packets
252 * between threads sending data to the relayd. Since metadata data is sent
253 * over that socket, at least two sendmsg() are needed (header + data)
254 * creating a race for packets to overlap between threads using it.
256 * This is nested INSIDE the consumer_data lock.
257 * This is nested INSIDE the stream lock.
259 pthread_mutex_t ctrl_sock_mutex
;
261 /* Control socket. Command and metadata are passed over it */
262 struct lttcomm_sock control_sock
;
265 * We don't need a mutex at this point since we only splice or write single
266 * large chunk of data with a header appended at the begining. Moreover,
267 * this socket is for now only used in a single thread.
269 struct lttcomm_sock data_sock
;
270 struct lttng_ht_node_u64 node
;
272 /* Session id on both sides for the sockets. */
273 uint64_t relayd_session_id
;
274 uint64_t sessiond_session_id
;
278 * UST consumer local data to the program. One or more instance per
281 struct lttng_consumer_local_data
{
283 * Function to call when data is available on a buffer.
284 * Returns the number of bytes read, or negative error value.
286 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
287 struct lttng_consumer_local_data
*ctx
);
289 * function to call when we receive a new channel, it receives a
290 * newly allocated channel, depending on the return code of this
291 * function, the new channel will be handled by the application
295 * > 0 (success, FD is kept by application)
296 * == 0 (success, FD is left to library)
299 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
301 * function to call when we receive a new stream, it receives a
302 * newly allocated stream, depending on the return code of this
303 * function, the new stream will be handled by the application
307 * > 0 (success, FD is kept by application)
308 * == 0 (success, FD is left to library)
311 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
313 * function to call when a stream is getting updated by the session
314 * daemon, this function receives the sessiond key and the new
315 * state, depending on the return code of this function the
316 * update of state for the stream is handled by the application
320 * > 0 (success, FD is kept by application)
321 * == 0 (success, FD is left to library)
324 int (*on_update_stream
)(int sessiond_key
, uint32_t state
);
325 /* socket to communicate errors with sessiond */
326 int consumer_error_socket
;
327 /* socket to exchange commands with sessiond */
328 char *consumer_command_sock_path
;
329 /* communication with splice */
330 int consumer_thread_pipe
[2];
331 int consumer_channel_pipe
[2];
332 int consumer_splice_metadata_pipe
[2];
333 /* Data stream poll thread pipe. To transfer data stream to the thread */
334 int consumer_data_pipe
[2];
335 /* to let the signal handler wake up the fd receiver thread */
336 int consumer_should_quit
[2];
337 /* Metadata poll thread pipe. Transfer metadata stream to it */
338 int consumer_metadata_pipe
[2];
342 * Library-level data. One instance per process.
344 struct lttng_consumer_global_data
{
346 * At this time, this lock is used to ensure coherence between the count
347 * and number of element in the hash table. It's also a protection for
348 * concurrent read/write between threads.
350 * This is nested OUTSIDE the stream lock.
351 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
353 pthread_mutex_t lock
;
356 * Number of streams in the data stream hash table declared outside.
357 * Protected by consumer_data.lock.
361 /* Channel hash table protected by consumer_data.lock. */
362 struct lttng_ht
*channel_ht
;
364 * Flag specifying if the local array of FDs needs update in the
365 * poll function. Protected by consumer_data.lock.
367 unsigned int need_update
;
368 enum lttng_consumer_type type
;
371 * Relayd socket(s) hashtable indexed by network sequence number. Each
372 * stream has an index which associate the right relayd socket to use.
374 struct lttng_ht
*relayd_ht
;
377 * This hash table contains all streams (metadata and data) indexed by
378 * session id. In other words, the ht is indexed by session id and each
379 * bucket contains the list of associated streams.
381 * This HT uses the "node_session_id" of the consumer stream.
383 struct lttng_ht
*stream_list_ht
;
386 * This HT uses the "node_channel_id" of the consumer stream.
388 struct lttng_ht
*stream_per_chan_id_ht
;
392 * Init consumer data structures.
394 void lttng_consumer_init(void);
397 * Set the error socket for communication with a session daemon.
399 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
403 * Set the command socket path for communication with a session daemon.
405 void lttng_consumer_set_command_sock_path(
406 struct lttng_consumer_local_data
*ctx
, char *sock
);
409 * Send return code to session daemon.
411 * Returns the return code of sendmsg : the number of bytes transmitted or -1
414 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
417 * Called from signal handler to ensure a clean exit.
419 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
422 * Cleanup the daemon's socket on exit.
424 void lttng_consumer_cleanup(void);
427 * Flush pending writes to trace output disk file.
429 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
433 * Poll on the should_quit pipe and the command socket return -1 on error and
434 * should exit, 0 if data is available on the command socket
436 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
438 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
440 enum lttng_consumer_stream_state state
,
441 const char *channel_name
,
448 enum consumer_channel_type type
);
449 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
451 const char *pathname
,
456 enum lttng_event_output output
);
457 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
458 struct lttng_ht
*ht
);
459 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
460 struct lttng_ht
*ht
);
461 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
462 struct lttng_consumer_local_data
*ctx
);
463 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
465 /* lttng-relayd consumer command */
466 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
468 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
469 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
470 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
472 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
474 struct lttng_consumer_local_data
*lttng_consumer_create(
475 enum lttng_consumer_type type
,
476 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
477 struct lttng_consumer_local_data
*ctx
),
478 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
479 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
480 int (*update_stream
)(int sessiond_key
, uint32_t state
));
481 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
482 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
483 struct lttng_consumer_local_data
*ctx
,
484 struct lttng_consumer_stream
*stream
, unsigned long len
,
485 unsigned long padding
);
486 ssize_t
lttng_consumer_on_read_subbuffer_splice(
487 struct lttng_consumer_local_data
*ctx
,
488 struct lttng_consumer_stream
*stream
, unsigned long len
,
489 unsigned long padding
);
490 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
491 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
493 void *consumer_thread_metadata_poll(void *data
);
494 void *consumer_thread_data_poll(void *data
);
495 void *consumer_thread_sessiond_poll(void *data
);
496 void *consumer_thread_channel_poll(void *data
);
497 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
498 int sock
, struct pollfd
*consumer_sockpoll
);
500 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
501 struct lttng_consumer_local_data
*ctx
);
502 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
503 int consumer_add_relayd_socket(int net_seq_idx
, int sock_type
,
504 struct lttng_consumer_local_data
*ctx
, int sock
,
505 struct pollfd
*consumer_sockpoll
, struct lttcomm_sock
*relayd_sock
,
506 unsigned int sessiond_id
);
507 void consumer_flag_relayd_for_destroy(
508 struct consumer_relayd_sock_pair
*relayd
);
509 int consumer_data_pending(uint64_t id
);
510 int consumer_send_status_msg(int sock
, int ret_code
);
511 int consumer_send_status_channel(int sock
,
512 struct lttng_consumer_channel
*channel
);
514 #endif /* LIB_CONSUMER_H */