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. */
109 /* Channel trace file path name. */
110 char pathname
[PATH_MAX
];
112 char name
[LTTNG_SYMBOL_NAME_LEN
];
113 /* UID and GID of the channel. */
116 /* Relayd id of the channel. -1 if it does not apply. */
119 * Number of streams NOT initialized yet. This is used in order to not
120 * delete this channel if streams are getting initialized.
122 unsigned int nb_init_stream_left
;
123 /* Output type (mmap or splice). */
124 enum consumer_channel_output output
;
125 /* Channel type for stream */
126 enum consumer_channel_type type
;
129 struct ustctl_consumer_channel
*uchan
;
130 unsigned char uuid
[UUID_STR_LEN
];
132 * Temporary stream list used to store the streams once created and waiting
133 * to be sent to the session daemon by receiving the
134 * LTTNG_CONSUMER_GET_CHANNEL.
136 struct stream_list streams
;
138 * Set if the channel is metadata. We keep a reference to the stream
139 * because we have to flush data once pushed by the session daemon. For a
140 * regular channel, this is always set to NULL.
142 struct lttng_consumer_stream
*metadata_stream
;
146 /* Node within channel thread ht */
147 struct lttng_ht_node_u64 wait_fd_node
;
149 /* Metadata cache is metadata channel */
150 struct consumer_metadata_cache
*metadata_cache
;
151 /* For metadata periodical flush */
152 int switch_timer_enabled
;
153 timer_t switch_timer
;
154 int switch_timer_error
;
156 /* On-disk circular buffer */
157 uint64_t tracefile_size
;
158 uint64_t tracefile_count
;
160 * Monitor or not the streams of this channel meaning this indicates if the
161 * streams should be sent to the data/metadata thread or added to the no
162 * monitor list of the channel.
164 unsigned int monitor
;
168 * Internal representation of the streams, sessiond_key is used to identify
171 struct lttng_consumer_stream
{
172 /* HT node used by the data_ht and metadata_ht */
173 struct lttng_ht_node_u64 node
;
174 /* stream indexed per channel key node */
175 struct lttng_ht_node_u64 node_channel_id
;
176 /* HT node used in consumer_data.stream_list_ht */
177 struct lttng_ht_node_u64 node_session_id
;
178 /* Pointer to associated channel. */
179 struct lttng_consumer_channel
*chan
;
181 /* Key by which the stream is indexed for 'node'. */
184 * File descriptor of the data output file. This can be either a file or a
185 * socket fd for relayd streaming.
187 int out_fd
; /* output file to write the data */
188 /* Write position in the output file descriptor */
190 enum lttng_consumer_stream_state state
;
193 int hangup_flush_done
;
194 enum lttng_event_output output
;
195 /* Maximum subbuffer size. */
196 unsigned long max_sb_size
;
199 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
200 * used for the mmap base and offset.
203 unsigned long mmap_len
;
208 /* UID/GID of the user owning the session to which stream belongs */
211 /* Network sequence number. Indicating on which relayd socket it goes. */
212 uint64_t net_seq_idx
;
213 /* Identify if the stream is the metadata */
214 unsigned int metadata_flag
;
215 /* Used when the stream is set for network streaming */
216 uint64_t relayd_stream_id
;
218 * When sending a stream packet to a relayd, this number is used to track
219 * the packet sent by the consumer and seen by the relayd. When sending the
220 * data header to the relayd, this number is sent and if the transmission
221 * was successful, it is incremented.
223 * Even if the full data is not fully transmitted it won't matter since
224 * only two possible error can happen after that where either the relayd
225 * died or a read error is detected on the stream making this value useless
228 * This value SHOULD be read/updated atomically or with the lock acquired.
230 uint64_t next_net_seq_num
;
232 * Lock to use the stream FDs since they are used between threads.
234 * This is nested INSIDE the consumer_data lock.
235 * This is nested INSIDE the metadata cache lock.
236 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
238 pthread_mutex_t lock
;
239 /* Tracing session id */
242 * Indicates if the stream end point is still active or not (network
243 * streaming or local file system). The thread "owning" the stream is
244 * handling this status and can be notified of a state change through the
245 * consumer data appropriate pipe.
247 enum consumer_endpoint_status endpoint_status
;
248 /* Stream name. Format is: <channel_name>_<cpu_number> */
249 char name
[LTTNG_SYMBOL_NAME_LEN
];
250 /* Internal state of libustctl. */
251 struct ustctl_consumer_stream
*ustream
;
252 struct cds_list_head send_node
;
253 /* On-disk circular buffer */
254 uint64_t tracefile_size_current
;
255 uint64_t tracefile_count_current
;
259 * Internal representation of a relayd socket pair.
261 struct consumer_relayd_sock_pair
{
262 /* Network sequence number. */
264 /* Number of stream associated with this relayd */
265 unsigned int refcount
;
268 * This flag indicates whether or not we should destroy this object. The
269 * destruction should ONLY occurs when this flag is set and the refcount is
272 unsigned int destroy_flag
;
275 * Mutex protecting the control socket to avoid out of order packets
276 * between threads sending data to the relayd. Since metadata data is sent
277 * over that socket, at least two sendmsg() are needed (header + data)
278 * creating a race for packets to overlap between threads using it.
280 * This is nested INSIDE the consumer_data lock.
281 * This is nested INSIDE the stream lock.
283 pthread_mutex_t ctrl_sock_mutex
;
285 /* Control socket. Command and metadata are passed over it */
286 struct lttcomm_relayd_sock control_sock
;
289 * We don't need a mutex at this point since we only splice or write single
290 * large chunk of data with a header appended at the begining. Moreover,
291 * this socket is for now only used in a single thread.
293 struct lttcomm_relayd_sock data_sock
;
294 struct lttng_ht_node_u64 node
;
296 /* Session id on both sides for the sockets. */
297 uint64_t relayd_session_id
;
298 uint64_t sessiond_session_id
;
302 * UST consumer local data to the program. One or more instance per
305 struct lttng_consumer_local_data
{
307 * Function to call when data is available on a buffer.
308 * Returns the number of bytes read, or negative error value.
310 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
311 struct lttng_consumer_local_data
*ctx
);
313 * function to call when we receive a new channel, it receives a
314 * newly allocated channel, depending on the return code of this
315 * function, the new channel will be handled by the application
319 * > 0 (success, FD is kept by application)
320 * == 0 (success, FD is left to library)
323 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
325 * function to call when we receive a new stream, it receives a
326 * newly allocated stream, depending on the return code of this
327 * function, the new stream will be handled by the application
331 * > 0 (success, FD is kept by application)
332 * == 0 (success, FD is left to library)
335 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
337 * function to call when a stream is getting updated by the session
338 * daemon, this function receives the sessiond key and the new
339 * state, depending on the return code of this function the
340 * update of state for the stream is handled by the application
344 * > 0 (success, FD is kept by application)
345 * == 0 (success, FD is left to library)
348 int (*on_update_stream
)(int sessiond_key
, uint32_t state
);
349 enum lttng_consumer_type type
;
350 /* socket to communicate errors with sessiond */
351 int consumer_error_socket
;
352 /* socket to ask metadata to sessiond */
353 int consumer_metadata_socket
;
354 /* socket to exchange commands with sessiond */
355 char *consumer_command_sock_path
;
356 /* communication with splice */
357 int consumer_thread_pipe
[2];
358 int consumer_channel_pipe
[2];
359 int consumer_splice_metadata_pipe
[2];
360 /* Data stream poll thread pipe. To transfer data stream to the thread */
361 struct lttng_pipe
*consumer_data_pipe
;
362 /* to let the signal handler wake up the fd receiver thread */
363 int consumer_should_quit
[2];
364 /* Metadata poll thread pipe. Transfer metadata stream to it */
365 struct lttng_pipe
*consumer_metadata_pipe
;
369 * Library-level data. One instance per process.
371 struct lttng_consumer_global_data
{
373 * At this time, this lock is used to ensure coherence between the count
374 * and number of element in the hash table. It's also a protection for
375 * concurrent read/write between threads.
377 * This is nested OUTSIDE the stream lock.
378 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
380 pthread_mutex_t lock
;
383 * Number of streams in the data stream hash table declared outside.
384 * Protected by consumer_data.lock.
388 /* Channel hash table protected by consumer_data.lock. */
389 struct lttng_ht
*channel_ht
;
391 * Flag specifying if the local array of FDs needs update in the
392 * poll function. Protected by consumer_data.lock.
394 unsigned int need_update
;
395 enum lttng_consumer_type type
;
398 * Relayd socket(s) hashtable indexed by network sequence number. Each
399 * stream has an index which associate the right relayd socket to use.
401 struct lttng_ht
*relayd_ht
;
404 * This hash table contains all streams (metadata and data) indexed by
405 * session id. In other words, the ht is indexed by session id and each
406 * bucket contains the list of associated streams.
408 * This HT uses the "node_session_id" of the consumer stream.
410 struct lttng_ht
*stream_list_ht
;
413 * This HT uses the "node_channel_id" of the consumer stream.
415 struct lttng_ht
*stream_per_chan_id_ht
;
419 * Init consumer data structures.
421 void lttng_consumer_init(void);
424 * Set the error socket for communication with a session daemon.
426 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
430 * Set the command socket path for communication with a session daemon.
432 void lttng_consumer_set_command_sock_path(
433 struct lttng_consumer_local_data
*ctx
, char *sock
);
436 * Send return code to session daemon.
438 * Returns the return code of sendmsg : the number of bytes transmitted or -1
441 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
444 * Called from signal handler to ensure a clean exit.
446 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
449 * Cleanup the daemon's socket on exit.
451 void lttng_consumer_cleanup(void);
454 * Flush pending writes to trace output disk file.
456 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
460 * Poll on the should_quit pipe and the command socket return -1 on error and
461 * should exit, 0 if data is available on the command socket
463 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
465 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
467 enum lttng_consumer_stream_state state
,
468 const char *channel_name
,
475 enum consumer_channel_type type
);
476 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
478 const char *pathname
,
483 enum lttng_event_output output
,
484 uint64_t tracefile_size
,
485 uint64_t tracefile_count
,
486 unsigned int monitor
);
487 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
488 struct lttng_ht
*ht
);
489 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
490 struct lttng_ht
*ht
);
491 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
492 struct lttng_consumer_local_data
*ctx
);
493 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
495 /* lttng-relayd consumer command */
496 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
498 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
499 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
500 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
502 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
504 struct lttng_consumer_local_data
*lttng_consumer_create(
505 enum lttng_consumer_type type
,
506 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
507 struct lttng_consumer_local_data
*ctx
),
508 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
509 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
510 int (*update_stream
)(int sessiond_key
, uint32_t state
));
511 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
512 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
513 struct lttng_consumer_local_data
*ctx
,
514 struct lttng_consumer_stream
*stream
, unsigned long len
,
515 unsigned long padding
);
516 ssize_t
lttng_consumer_on_read_subbuffer_splice(
517 struct lttng_consumer_local_data
*ctx
,
518 struct lttng_consumer_stream
*stream
, unsigned long len
,
519 unsigned long padding
);
520 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
521 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
523 void *consumer_thread_metadata_poll(void *data
);
524 void *consumer_thread_data_poll(void *data
);
525 void *consumer_thread_sessiond_poll(void *data
);
526 void *consumer_thread_channel_poll(void *data
);
527 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
528 int sock
, struct pollfd
*consumer_sockpoll
);
530 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
531 struct lttng_consumer_local_data
*ctx
);
532 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
533 int consumer_add_relayd_socket(int net_seq_idx
, int sock_type
,
534 struct lttng_consumer_local_data
*ctx
, int sock
,
535 struct pollfd
*consumer_sockpoll
, struct lttcomm_relayd_sock
*relayd_sock
,
536 unsigned int sessiond_id
);
537 void consumer_flag_relayd_for_destroy(
538 struct consumer_relayd_sock_pair
*relayd
);
539 int consumer_data_pending(uint64_t id
);
540 int consumer_send_status_msg(int sock
, int ret_code
);
541 int consumer_send_status_channel(int sock
,
542 struct lttng_consumer_channel
*channel
);
543 void notify_thread_del_channel(struct lttng_consumer_local_data
*ctx
,
545 void consumer_destroy_relayd(struct consumer_relayd_sock_pair
*relayd
);
547 #endif /* LIB_CONSUMER_H */