Tests: Fix nprocesses applications shutdown
[lttng-tools.git] / src / common / consumer.h
1 /*
2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * 2012 - David Goulet <dgoulet@efficios.com>
5 *
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.
9 *
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
13 * more details.
14 *
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.
18 */
19
20 #ifndef LIB_CONSUMER_H
21 #define LIB_CONSUMER_H
22
23 #include <limits.h>
24 #include <poll.h>
25 #include <unistd.h>
26 #include <urcu/list.h>
27
28 #include <lttng/lttng.h>
29
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
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 */
42 LTTNG_CONSUMER_STOP,
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,
56 };
57
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,
63 };
64
65 enum lttng_consumer_type {
66 LTTNG_CONSUMER_UNKNOWN = 0,
67 LTTNG_CONSUMER_KERNEL,
68 LTTNG_CONSUMER64_UST,
69 LTTNG_CONSUMER32_UST,
70 };
71
72 enum consumer_endpoint_status {
73 CONSUMER_ENDPOINT_ACTIVE,
74 CONSUMER_ENDPOINT_INACTIVE,
75 };
76
77 enum consumer_channel_output {
78 CONSUMER_CHANNEL_MMAP = 0,
79 CONSUMER_CHANNEL_SPLICE = 1,
80 };
81
82 enum consumer_channel_type {
83 CONSUMER_CHANNEL_TYPE_METADATA = 0,
84 CONSUMER_CHANNEL_TYPE_DATA = 1,
85 };
86
87 struct stream_list {
88 struct cds_list_head head;
89 unsigned int count;
90 };
91
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. */
96 uint64_t key;
97 /* Number of streams referencing this channel */
98 int refcount;
99 /* Tracing session id on the session daemon side. */
100 uint64_t session_id;
101 /* Channel trace file path name. */
102 char pathname[PATH_MAX];
103 /* Channel name. */
104 char name[LTTNG_SYMBOL_NAME_LEN];
105 /* UID and GID of the channel. */
106 uid_t uid;
107 gid_t gid;
108 /* Relayd id of the channel. -1 if it does not apply. */
109 int64_t relayd_id;
110 /*
111 * Number of streams NOT initialized yet. This is used in order to not
112 * delete this channel if streams are getting initialized.
113 */
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;
119
120 /* For UST */
121 struct ustctl_consumer_channel *uchan;
122 unsigned char uuid[UUID_STR_LEN];
123 /*
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.
127 */
128 struct stream_list streams;
129 /*
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.
133 */
134 struct lttng_consumer_stream *metadata_stream;
135 /*
136 * Metadata written so far. Helps keeping track of
137 * contiguousness and order.
138 */
139 uint64_t contig_metadata_written;
140
141 /* for UST */
142 int wait_fd;
143 /* Node within channel thread ht */
144 struct lttng_ht_node_u64 wait_fd_node;
145 };
146
147 /*
148 * Internal representation of the streams, sessiond_key is used to identify
149 * uniquely a stream.
150 */
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;
160
161 /* Key by which the stream is indexed for 'node'. */
162 uint64_t key;
163 /*
164 * File descriptor of the data output file. This can be either a file or a
165 * socket fd for relayd streaming.
166 */
167 int out_fd; /* output file to write the data */
168 /* Write position in the output file descriptor */
169 off_t out_fd_offset;
170 enum lttng_consumer_stream_state state;
171 int shm_fd_is_copy;
172 int data_read;
173 int hangup_flush_done;
174 enum lttng_event_output output;
175 /* Maximum subbuffer size. */
176 unsigned long max_sb_size;
177
178 /*
179 * Still used by the kernel for MMAP output. For UST, the ustctl getter is
180 * used for the mmap base and offset.
181 */
182 void *mmap_base;
183 unsigned long mmap_len;
184
185 /* For UST */
186
187 int wait_fd;
188 /* UID/GID of the user owning the session to which stream belongs */
189 uid_t uid;
190 gid_t gid;
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;
197 /*
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.
202 *
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
206 * after that.
207 *
208 * This value SHOULD be read/updated atomically or with the lock acquired.
209 */
210 uint64_t next_net_seq_num;
211 /*
212 * Lock to use the stream FDs since they are used between threads.
213 *
214 * This is nested INSIDE the consumer_data lock.
215 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
216 */
217 pthread_mutex_t lock;
218 /* Tracing session id */
219 uint64_t session_id;
220 /*
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.
225 */
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;
232 };
233
234 /*
235 * Internal representation of a relayd socket pair.
236 */
237 struct consumer_relayd_sock_pair {
238 /* Network sequence number. */
239 int64_t net_seq_idx;
240 /* Number of stream associated with this relayd */
241 unsigned int refcount;
242
243 /*
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
246 * set to zero.
247 */
248 unsigned int destroy_flag;
249
250 /*
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.
255 *
256 * This is nested INSIDE the consumer_data lock.
257 * This is nested INSIDE the stream lock.
258 */
259 pthread_mutex_t ctrl_sock_mutex;
260
261 /* Control socket. Command and metadata are passed over it */
262 struct lttcomm_sock control_sock;
263
264 /*
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.
268 */
269 struct lttcomm_sock data_sock;
270 struct lttng_ht_node_u64 node;
271
272 /* Session id on both sides for the sockets. */
273 uint64_t relayd_session_id;
274 uint64_t sessiond_session_id;
275 };
276
277 /*
278 * UST consumer local data to the program. One or more instance per
279 * process.
280 */
281 struct lttng_consumer_local_data {
282 /*
283 * Function to call when data is available on a buffer.
284 * Returns the number of bytes read, or negative error value.
285 */
286 ssize_t (*on_buffer_ready)(struct lttng_consumer_stream *stream,
287 struct lttng_consumer_local_data *ctx);
288 /*
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
292 * or the library.
293 *
294 * Returns:
295 * > 0 (success, FD is kept by application)
296 * == 0 (success, FD is left to library)
297 * < 0 (error)
298 */
299 int (*on_recv_channel)(struct lttng_consumer_channel *channel);
300 /*
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
304 * or the library.
305 *
306 * Returns:
307 * > 0 (success, FD is kept by application)
308 * == 0 (success, FD is left to library)
309 * < 0 (error)
310 */
311 int (*on_recv_stream)(struct lttng_consumer_stream *stream);
312 /*
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
317 * or the library.
318 *
319 * Returns:
320 * > 0 (success, FD is kept by application)
321 * == 0 (success, FD is left to library)
322 * < 0 (error)
323 */
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];
339 };
340
341 /*
342 * Library-level data. One instance per process.
343 */
344 struct lttng_consumer_global_data {
345 /*
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.
349 *
350 * This is nested OUTSIDE the stream lock.
351 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
352 */
353 pthread_mutex_t lock;
354
355 /*
356 * Number of streams in the data stream hash table declared outside.
357 * Protected by consumer_data.lock.
358 */
359 int stream_count;
360
361 /* Channel hash table protected by consumer_data.lock. */
362 struct lttng_ht *channel_ht;
363 /*
364 * Flag specifying if the local array of FDs needs update in the
365 * poll function. Protected by consumer_data.lock.
366 */
367 unsigned int need_update;
368 enum lttng_consumer_type type;
369
370 /*
371 * Relayd socket(s) hashtable indexed by network sequence number. Each
372 * stream has an index which associate the right relayd socket to use.
373 */
374 struct lttng_ht *relayd_ht;
375
376 /*
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.
380 *
381 * This HT uses the "node_session_id" of the consumer stream.
382 */
383 struct lttng_ht *stream_list_ht;
384
385 /*
386 * This HT uses the "node_channel_id" of the consumer stream.
387 */
388 struct lttng_ht *stream_per_chan_id_ht;
389 };
390
391 /*
392 * Init consumer data structures.
393 */
394 void lttng_consumer_init(void);
395
396 /*
397 * Set the error socket for communication with a session daemon.
398 */
399 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data *ctx,
400 int sock);
401
402 /*
403 * Set the command socket path for communication with a session daemon.
404 */
405 void lttng_consumer_set_command_sock_path(
406 struct lttng_consumer_local_data *ctx, char *sock);
407
408 /*
409 * Send return code to session daemon.
410 *
411 * Returns the return code of sendmsg : the number of bytes transmitted or -1
412 * on error.
413 */
414 int lttng_consumer_send_error(struct lttng_consumer_local_data *ctx, int cmd);
415
416 /*
417 * Called from signal handler to ensure a clean exit.
418 */
419 void lttng_consumer_should_exit(struct lttng_consumer_local_data *ctx);
420
421 /*
422 * Cleanup the daemon's socket on exit.
423 */
424 void lttng_consumer_cleanup(void);
425
426 /*
427 * Flush pending writes to trace output disk file.
428 */
429 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream *stream,
430 off_t orig_offset);
431
432 /*
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
435 */
436 int lttng_consumer_poll_socket(struct pollfd *kconsumer_sockpoll);
437
438 struct lttng_consumer_stream *consumer_allocate_stream(uint64_t channel_key,
439 uint64_t stream_key,
440 enum lttng_consumer_stream_state state,
441 const char *channel_name,
442 uid_t uid,
443 gid_t gid,
444 int relayd_id,
445 uint64_t session_id,
446 int cpu,
447 int *alloc_ret,
448 enum consumer_channel_type type);
449 struct lttng_consumer_channel *consumer_allocate_channel(uint64_t key,
450 uint64_t session_id,
451 const char *pathname,
452 const char *name,
453 uid_t uid,
454 gid_t gid,
455 int relayd_id,
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);
464
465 /* lttng-relayd consumer command */
466 struct consumer_relayd_sock_pair *consumer_allocate_relayd_sock_pair(
467 int net_seq_idx);
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,
471 size_t data_size);
472 void consumer_steal_stream_key(int key, struct lttng_ht *ht);
473
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,
492 unsigned long *pos);
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);
499
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);
513
514 #endif /* LIB_CONSUMER_H */
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