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
,
57 /* State of each fd in consumer */
58 enum lttng_consumer_stream_state
{
59 LTTNG_CONSUMER_ACTIVE_STREAM
,
60 LTTNG_CONSUMER_PAUSE_STREAM
,
61 LTTNG_CONSUMER_DELETE_STREAM
,
64 enum lttng_consumer_type
{
65 LTTNG_CONSUMER_UNKNOWN
= 0,
66 LTTNG_CONSUMER_KERNEL
,
71 enum consumer_endpoint_status
{
72 CONSUMER_ENDPOINT_ACTIVE
,
73 CONSUMER_ENDPOINT_INACTIVE
,
76 enum consumer_channel_output
{
77 CONSUMER_CHANNEL_MMAP
= 0,
78 CONSUMER_CHANNEL_SPLICE
= 1,
81 enum consumer_channel_type
{
82 CONSUMER_CHANNEL_TYPE_METADATA
= 0,
83 CONSUMER_CHANNEL_TYPE_DATA
= 1,
87 struct cds_list_head head
;
91 struct lttng_consumer_channel
{
92 /* HT node used for consumer_data.channel_ht */
93 struct lttng_ht_node_u64 node
;
94 /* Indexed key. Incremented value in the consumer. */
96 /* Number of streams referencing this channel */
98 /* Tracing session id on the session daemon side. */
100 /* Channel trace file path name. */
101 char pathname
[PATH_MAX
];
103 char name
[LTTNG_SYMBOL_NAME_LEN
];
104 /* UID and GID of the channel. */
107 /* Relayd id of the channel. -1 if it does not apply. */
110 * Number of streams NOT initialized yet. This is used in order to not
111 * delete this channel if streams are getting initialized.
113 unsigned int nb_init_stream_left
;
114 /* Output type (mmap or splice). */
115 enum consumer_channel_output output
;
116 /* Channel type for stream */
117 enum consumer_channel_type type
;
120 struct ustctl_consumer_channel
*uchan
;
121 unsigned char uuid
[UUID_STR_LEN
];
123 * Temporary stream list used to store the streams once created and waiting
124 * to be sent to the session daemon by receiving the
125 * LTTNG_CONSUMER_GET_CHANNEL.
127 struct stream_list streams
;
129 * Set if the channel is metadata. We keep a reference to the stream
130 * because we have to flush data once pushed by the session daemon. For a
131 * regular channel, this is always set to NULL.
133 struct lttng_consumer_stream
*metadata_stream
;
135 * Metadata written so far. Helps keeping track of
136 * contiguousness and order.
138 uint64_t contig_metadata_written
;
142 /* Node within channel thread ht */
143 struct lttng_ht_node_u64 wait_fd_node
;
147 * Internal representation of the streams, sessiond_key is used to identify
150 struct lttng_consumer_stream
{
151 /* HT node used by the data_ht and metadata_ht */
152 struct lttng_ht_node_u64 node
;
153 /* stream indexed per channel key node */
154 struct lttng_ht_node_u64 node_channel_id
;
155 /* HT node used in consumer_data.stream_list_ht */
156 struct lttng_ht_node_u64 node_session_id
;
157 /* Pointer to associated channel. */
158 struct lttng_consumer_channel
*chan
;
160 /* Key by which the stream is indexed for 'node'. */
163 * File descriptor of the data output file. This can be either a file or a
164 * socket fd for relayd streaming.
166 int out_fd
; /* output file to write the data */
167 /* Write position in the output file descriptor */
169 enum lttng_consumer_stream_state state
;
172 int hangup_flush_done
;
173 enum lttng_event_output output
;
174 /* Maximum subbuffer size. */
175 unsigned long max_sb_size
;
178 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
179 * used for the mmap base and offset.
182 unsigned long mmap_len
;
187 /* UID/GID of the user owning the session to which stream belongs */
190 /* Network sequence number. Indicating on which relayd socket it goes. */
191 uint64_t net_seq_idx
;
192 /* Identify if the stream is the metadata */
193 unsigned int metadata_flag
;
194 /* Used when the stream is set for network streaming */
195 uint64_t relayd_stream_id
;
197 * When sending a stream packet to a relayd, this number is used to track
198 * the packet sent by the consumer and seen by the relayd. When sending the
199 * data header to the relayd, this number is sent and if the transmission
200 * was successful, it is incremented.
202 * Even if the full data is not fully transmitted it won't matter since
203 * only two possible error can happen after that where either the relayd
204 * died or a read error is detected on the stream making this value useless
207 * This value SHOULD be read/updated atomically or with the lock acquired.
209 uint64_t next_net_seq_num
;
211 * Lock to use the stream FDs since they are used between threads.
213 * This is nested INSIDE the consumer_data lock.
214 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
216 pthread_mutex_t lock
;
217 /* Tracing session id */
220 * Indicates if the stream end point is still active or not (network
221 * streaming or local file system). The thread "owning" the stream is
222 * handling this status and can be notified of a state change through the
223 * consumer data appropriate pipe.
225 enum consumer_endpoint_status endpoint_status
;
226 /* Stream name. Format is: <channel_name>_<cpu_number> */
227 char name
[LTTNG_SYMBOL_NAME_LEN
];
228 /* Internal state of libustctl. */
229 struct ustctl_consumer_stream
*ustream
;
230 struct cds_list_head send_node
;
234 * Internal representation of a relayd socket pair.
236 struct consumer_relayd_sock_pair
{
237 /* Network sequence number. */
239 /* Number of stream associated with this relayd */
240 unsigned int refcount
;
243 * This flag indicates whether or not we should destroy this object. The
244 * destruction should ONLY occurs when this flag is set and the refcount is
247 unsigned int destroy_flag
;
250 * Mutex protecting the control socket to avoid out of order packets
251 * between threads sending data to the relayd. Since metadata data is sent
252 * over that socket, at least two sendmsg() are needed (header + data)
253 * creating a race for packets to overlap between threads using it.
255 * This is nested INSIDE the consumer_data lock.
256 * This is nested INSIDE the stream lock.
258 pthread_mutex_t ctrl_sock_mutex
;
260 /* Control socket. Command and metadata are passed over it */
261 struct lttcomm_sock control_sock
;
264 * We don't need a mutex at this point since we only splice or write single
265 * large chunk of data with a header appended at the begining. Moreover,
266 * this socket is for now only used in a single thread.
268 struct lttcomm_sock data_sock
;
269 struct lttng_ht_node_u64 node
;
271 /* Session id on both sides for the sockets. */
272 uint64_t relayd_session_id
;
273 uint64_t sessiond_session_id
;
277 * UST consumer local data to the program. One or more instance per
280 struct lttng_consumer_local_data
{
282 * Function to call when data is available on a buffer.
283 * Returns the number of bytes read, or negative error value.
285 ssize_t (*on_buffer_ready
)(struct lttng_consumer_stream
*stream
,
286 struct lttng_consumer_local_data
*ctx
);
288 * function to call when we receive a new channel, it receives a
289 * newly allocated channel, depending on the return code of this
290 * function, the new channel will be handled by the application
294 * > 0 (success, FD is kept by application)
295 * == 0 (success, FD is left to library)
298 int (*on_recv_channel
)(struct lttng_consumer_channel
*channel
);
300 * function to call when we receive a new stream, it receives a
301 * newly allocated stream, depending on the return code of this
302 * function, the new stream will be handled by the application
306 * > 0 (success, FD is kept by application)
307 * == 0 (success, FD is left to library)
310 int (*on_recv_stream
)(struct lttng_consumer_stream
*stream
);
312 * function to call when a stream is getting updated by the session
313 * daemon, this function receives the sessiond key and the new
314 * state, depending on the return code of this function the
315 * update of state for the stream is handled by the application
319 * > 0 (success, FD is kept by application)
320 * == 0 (success, FD is left to library)
323 int (*on_update_stream
)(int sessiond_key
, uint32_t state
);
324 /* socket to communicate errors with sessiond */
325 int consumer_error_socket
;
326 /* socket to exchange commands with sessiond */
327 char *consumer_command_sock_path
;
328 /* communication with splice */
329 int consumer_thread_pipe
[2];
330 int consumer_channel_pipe
[2];
331 int consumer_splice_metadata_pipe
[2];
332 /* Data stream poll thread pipe. To transfer data stream to the thread */
333 int consumer_data_pipe
[2];
334 /* to let the signal handler wake up the fd receiver thread */
335 int consumer_should_quit
[2];
336 /* Metadata poll thread pipe. Transfer metadata stream to it */
337 int consumer_metadata_pipe
[2];
341 * Library-level data. One instance per process.
343 struct lttng_consumer_global_data
{
345 * At this time, this lock is used to ensure coherence between the count
346 * and number of element in the hash table. It's also a protection for
347 * concurrent read/write between threads.
349 * This is nested OUTSIDE the stream lock.
350 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
352 pthread_mutex_t lock
;
355 * Number of streams in the data stream hash table declared outside.
356 * Protected by consumer_data.lock.
360 /* Channel hash table protected by consumer_data.lock. */
361 struct lttng_ht
*channel_ht
;
363 * Flag specifying if the local array of FDs needs update in the
364 * poll function. Protected by consumer_data.lock.
366 unsigned int need_update
;
367 enum lttng_consumer_type type
;
370 * Relayd socket(s) hashtable indexed by network sequence number. Each
371 * stream has an index which associate the right relayd socket to use.
373 struct lttng_ht
*relayd_ht
;
376 * This hash table contains all streams (metadata and data) indexed by
377 * session id. In other words, the ht is indexed by session id and each
378 * bucket contains the list of associated streams.
380 * This HT uses the "node_session_id" of the consumer stream.
382 struct lttng_ht
*stream_list_ht
;
385 * This HT uses the "node_channel_id" of the consumer stream.
387 struct lttng_ht
*stream_per_chan_id_ht
;
391 * Init consumer data structures.
393 void lttng_consumer_init(void);
396 * Set the error socket for communication with a session daemon.
398 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
402 * Set the command socket path for communication with a session daemon.
404 void lttng_consumer_set_command_sock_path(
405 struct lttng_consumer_local_data
*ctx
, char *sock
);
408 * Send return code to session daemon.
410 * Returns the return code of sendmsg : the number of bytes transmitted or -1
413 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
);
416 * Called from signal handler to ensure a clean exit.
418 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
);
421 * Cleanup the daemon's socket on exit.
423 void lttng_consumer_cleanup(void);
426 * Flush pending writes to trace output disk file.
428 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
432 * Poll on the should_quit pipe and the command socket return -1 on error and
433 * should exit, 0 if data is available on the command socket
435 int lttng_consumer_poll_socket(struct pollfd
*kconsumer_sockpoll
);
437 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
439 enum lttng_consumer_stream_state state
,
440 const char *channel_name
,
447 enum consumer_channel_type type
);
448 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
450 const char *pathname
,
455 enum lttng_event_output output
);
456 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
457 struct lttng_ht
*ht
);
458 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
459 struct lttng_ht
*ht
);
460 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
461 struct lttng_consumer_local_data
*ctx
);
462 void consumer_del_channel(struct lttng_consumer_channel
*channel
);
464 /* lttng-relayd consumer command */
465 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
467 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
);
468 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
);
469 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream
*stream
,
471 void consumer_steal_stream_key(int key
, struct lttng_ht
*ht
);
473 struct lttng_consumer_local_data
*lttng_consumer_create(
474 enum lttng_consumer_type type
,
475 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
476 struct lttng_consumer_local_data
*ctx
),
477 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
478 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
479 int (*update_stream
)(int sessiond_key
, uint32_t state
));
480 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
);
481 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
482 struct lttng_consumer_local_data
*ctx
,
483 struct lttng_consumer_stream
*stream
, unsigned long len
,
484 unsigned long padding
);
485 ssize_t
lttng_consumer_on_read_subbuffer_splice(
486 struct lttng_consumer_local_data
*ctx
,
487 struct lttng_consumer_stream
*stream
, unsigned long len
,
488 unsigned long padding
);
489 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
);
490 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
492 void *consumer_thread_metadata_poll(void *data
);
493 void *consumer_thread_data_poll(void *data
);
494 void *consumer_thread_sessiond_poll(void *data
);
495 void *consumer_thread_channel_poll(void *data
);
496 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
497 int sock
, struct pollfd
*consumer_sockpoll
);
499 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
500 struct lttng_consumer_local_data
*ctx
);
501 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
);
502 int consumer_add_relayd_socket(int net_seq_idx
, int sock_type
,
503 struct lttng_consumer_local_data
*ctx
, int sock
,
504 struct pollfd
*consumer_sockpoll
, struct lttcomm_sock
*relayd_sock
,
505 unsigned int sessiond_id
);
506 void consumer_flag_relayd_for_destroy(
507 struct consumer_relayd_sock_pair
*relayd
);
508 int consumer_data_pending(uint64_t id
);
509 int consumer_send_status_msg(int sock
, int ret_code
);
510 int consumer_send_status_channel(int sock
,
511 struct lttng_consumer_channel
*channel
);
513 #endif /* LIB_CONSUMER_H */