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
;
174 * Internal representation of the streams, sessiond_key is used to identify
177 struct lttng_consumer_stream
{
178 /* HT node used by the data_ht and metadata_ht */
179 struct lttng_ht_node_u64 node
;
180 /* stream indexed per channel key node */
181 struct lttng_ht_node_u64 node_channel_id
;
182 /* HT node used in consumer_data.stream_list_ht */
183 struct lttng_ht_node_u64 node_session_id
;
184 /* Pointer to associated channel. */
185 struct lttng_consumer_channel
*chan
;
187 /* Key by which the stream is indexed for 'node'. */
190 * File descriptor of the data output file. This can be either a file or a
191 * socket fd for relayd streaming.
193 int out_fd
; /* output file to write the data */
194 /* Write position in the output file descriptor */
196 enum lttng_consumer_stream_state state
;
199 int hangup_flush_done
;
200 enum lttng_event_output output
;
201 /* Maximum subbuffer size. */
202 unsigned long max_sb_size
;
205 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
206 * used for the mmap base and offset.
209 unsigned long mmap_len
;
214 /* UID/GID of the user owning the session to which stream belongs */
217 /* Network sequence number. Indicating on which relayd socket it goes. */
218 uint64_t net_seq_idx
;
219 /* Identify if the stream is the metadata */
220 unsigned int metadata_flag
;
221 /* Used when the stream is set for network streaming */
222 uint64_t relayd_stream_id
;
224 * When sending a stream packet to a relayd, this number is used to track
225 * the packet sent by the consumer and seen by the relayd. When sending the
226 * data header to the relayd, this number is sent and if the transmission
227 * was successful, it is incremented.
229 * Even if the full data is not fully transmitted it won't matter since
230 * only two possible error can happen after that where either the relayd
231 * died or a read error is detected on the stream making this value useless
234 * This value SHOULD be read/updated atomically or with the lock acquired.
236 uint64_t next_net_seq_num
;
238 * Lock to use the stream FDs since they are used between threads.
240 * This is nested INSIDE the consumer_data lock.
241 * This is nested INSIDE the metadata cache lock.
242 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
244 pthread_mutex_t lock
;
245 /* Tracing session id */
248 * Indicates if the stream end point is still active or not (network
249 * streaming or local file system). The thread "owning" the stream is
250 * handling this status and can be notified of a state change through the
251 * consumer data appropriate pipe.
253 enum consumer_endpoint_status endpoint_status
;
254 /* Stream name. Format is: <channel_name>_<cpu_number> */
255 char name
[LTTNG_SYMBOL_NAME_LEN
];
256 /* Internal state of libustctl. */
257 struct ustctl_consumer_stream
*ustream
;
258 struct cds_list_head send_node
;
259 /* On-disk circular buffer */
260 uint64_t tracefile_size_current
;
261 uint64_t tracefile_count_current
;
263 * Monitor or not the streams of this channel meaning this indicates if the
264 * streams should be sent to the data/metadata thread or added to the no
265 * monitor list of the channel.
267 unsigned int monitor
;
269 * Indicate if the stream is globally visible meaning that it has been
270 * added to the multiple hash tables. If *not* set, NO lock should be
271 * acquired in the destroy path.
273 unsigned int globally_visible
;
277 * Internal representation of a relayd socket pair.
279 struct consumer_relayd_sock_pair
{
280 /* Network sequence number. */
281 uint64_t net_seq_idx
;
282 /* Number of stream associated with this relayd */
283 unsigned int refcount
;
286 * This flag indicates whether or not we should destroy this object. The
287 * destruction should ONLY occurs when this flag is set and the refcount is
290 unsigned int destroy_flag
;
293 * Mutex protecting the control socket to avoid out of order packets
294 * between threads sending data to the relayd. Since metadata data is sent
295 * over that socket, at least two sendmsg() are needed (header + data)
296 * creating a race for packets to overlap between threads using it.
298 * This is nested INSIDE the consumer_data lock.
299 * This is nested INSIDE the stream lock.
301 pthread_mutex_t ctrl_sock_mutex
;
303 /* Control socket. Command and metadata are passed over it */
304 struct lttcomm_relayd_sock control_sock
;
307 * We don't need a mutex at this point since we only splice or write single
308 * large chunk of data with a header appended at the begining. Moreover,
309 * this socket is for now only used in a single thread.
311 struct lttcomm_relayd_sock data_sock
;
312 struct lttng_ht_node_u64 node
;
314 /* Session id on both sides for the sockets. */
315 uint64_t relayd_session_id
;
316 uint64_t sessiond_session_id
;
320 * UST consumer local data to the program. One or more instance per
323 struct lttng_consumer_local_data
{
325 * Function to call when data is available on a buffer.
326 * Returns the number of bytes read, or negative error value.
328 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
329 struct lttng_consumer_local_data
*ctx
);
331 * function to call when we receive a new channel, it receives a
332 * newly allocated channel, depending on the return code of this
333 * function, the new channel will be handled by the application
337 * > 0 (success, FD is kept by application)
338 * == 0 (success, FD is left to library)
341 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
343 * function to call when we receive a new stream, it receives a
344 * newly allocated stream, depending on the return code of this
345 * function, the new stream will be handled by the application
349 * > 0 (success, FD is kept by application)
350 * == 0 (success, FD is left to library)
353 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
355 * function to call when a stream is getting updated by the session
356 * daemon, this function receives the sessiond key and the new
357 * state, depending on the return code of this function the
358 * update of state for the stream is handled by the application
362 * > 0 (success, FD is kept by application)
363 * == 0 (success, FD is left to library)
366 int (*on_update_stream
)(int sessiond_key
, uint32_t state
);
367 enum lttng_consumer_type type
;
368 /* socket to communicate errors with sessiond */
369 int consumer_error_socket
;
370 /* socket to ask metadata to sessiond */
371 int consumer_metadata_socket
;
372 /* socket to exchange commands with sessiond */
373 char *consumer_command_sock_path
;
374 /* communication with splice */
375 int consumer_thread_pipe
[2];
376 int consumer_channel_pipe
[2];
377 int consumer_splice_metadata_pipe
[2];
378 /* Data stream poll thread pipe. To transfer data stream to the thread */
379 struct lttng_pipe
*consumer_data_pipe
;
380 /* to let the signal handler wake up the fd receiver thread */
381 int consumer_should_quit
[2];
382 /* Metadata poll thread pipe. Transfer metadata stream to it */
383 struct lttng_pipe
*consumer_metadata_pipe
;
387 * Library-level data. One instance per process.
389 struct lttng_consumer_global_data
{
391 * At this time, this lock is used to ensure coherence between the count
392 * and number of element in the hash table. It's also a protection for
393 * concurrent read/write between threads.
395 * This is nested OUTSIDE the stream lock.
396 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
398 pthread_mutex_t lock
;
401 * Number of streams in the data stream hash table declared outside.
402 * Protected by consumer_data.lock.
406 /* Channel hash table protected by consumer_data.lock. */
407 struct lttng_ht
*channel_ht
;
409 * Flag specifying if the local array of FDs needs update in the
410 * poll function. Protected by consumer_data.lock.
412 unsigned int need_update
;
413 enum lttng_consumer_type type
;
416 * Relayd socket(s) hashtable indexed by network sequence number. Each
417 * stream has an index which associate the right relayd socket to use.
419 struct lttng_ht
*relayd_ht
;
422 * This hash table contains all streams (metadata and data) indexed by
423 * session id. In other words, the ht is indexed by session id and each
424 * bucket contains the list of associated streams.
426 * This HT uses the "node_session_id" of the consumer stream.
428 struct lttng_ht
*stream_list_ht
;
431 * This HT uses the "node_channel_id" of the consumer stream.
433 struct lttng_ht
*stream_per_chan_id_ht
;
437 * Init consumer data structures.
439 void lttng_consumer_init(void);
442 * Set the error socket for communication with a session daemon.
444 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
448 * Set the command socket path for communication with a session daemon.
450 void lttng_consumer_set_command_sock_path(
451 struct lttng_consumer_local_data
*ctx
, char *sock
);
454 * Send return code to session daemon.
456 * Returns the return code of sendmsg : the number of bytes transmitted or -1
459 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
462 * Called from signal handler to ensure a clean exit.
464 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
467 * Cleanup the daemon's socket on exit.
469 void lttng_consumer_cleanup(void);
472 * Flush pending writes to trace output disk file.
474 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
478 * Poll on the should_quit pipe and the command socket return -1 on error and
479 * should exit, 0 if data is available on the command socket
481 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
483 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
485 enum lttng_consumer_stream_state state
,
486 const char *channel_name
,
493 enum consumer_channel_type type
,
494 unsigned int monitor
);
495 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
497 const char *pathname
,
502 enum lttng_event_output output
,
503 uint64_t tracefile_size
,
504 uint64_t tracefile_count
,
505 uint64_t session_id_per_pid
,
506 unsigned int monitor
);
507 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
508 struct lttng_ht
*ht
);
509 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
510 struct lttng_ht
*ht
);
511 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
512 struct lttng_consumer_local_data
*ctx
);
513 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
515 /* lttng-relayd consumer command */
516 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
517 uint64_t net_seq_idx
);
518 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
519 int consumer_send_relayd_stream(struct lttng_consumer_stream
*stream
, char *path
);
520 void close_relayd_stream(struct lttng_consumer_stream
*stream
);
521 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
522 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
524 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
526 struct lttng_consumer_local_data
*lttng_consumer_create(
527 enum lttng_consumer_type type
,
528 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
529 struct lttng_consumer_local_data
*ctx
),
530 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
531 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
532 int (*update_stream
)(int sessiond_key
, uint32_t state
));
533 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
534 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
535 struct lttng_consumer_local_data
*ctx
,
536 struct lttng_consumer_stream
*stream
, unsigned long len
,
537 unsigned long padding
);
538 ssize_t
lttng_consumer_on_read_subbuffer_splice(
539 struct lttng_consumer_local_data
*ctx
,
540 struct lttng_consumer_stream
*stream
, unsigned long len
,
541 unsigned long padding
);
542 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
543 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
545 void *consumer_thread_metadata_poll(void *data
);
546 void *consumer_thread_data_poll(void *data
);
547 void *consumer_thread_sessiond_poll(void *data
);
548 void *consumer_thread_channel_poll(void *data
);
549 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
550 int sock
, struct pollfd
*consumer_sockpoll
);
552 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
553 struct lttng_consumer_local_data
*ctx
);
554 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
555 int consumer_add_relayd_socket(uint64_t net_seq_idx
, int sock_type
,
556 struct lttng_consumer_local_data
*ctx
, int sock
,
557 struct pollfd
*consumer_sockpoll
, struct lttcomm_relayd_sock
*relayd_sock
,
558 unsigned int sessiond_id
);
559 void consumer_flag_relayd_for_destroy(
560 struct consumer_relayd_sock_pair
*relayd
);
561 int consumer_data_pending(uint64_t id
);
562 int consumer_send_status_msg(int sock
, int ret_code
);
563 int consumer_send_status_channel(int sock
,
564 struct lttng_consumer_channel
*channel
);
565 void notify_thread_del_channel(struct lttng_consumer_local_data
*ctx
,
567 void consumer_destroy_relayd(struct consumer_relayd_sock_pair
*relayd
);
569 #endif /* LIB_CONSUMER_H */