Fix: remove unused session id map
[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
27 #include <lttng/lttng.h>
28
29 #include <common/hashtable/hashtable.h>
30 #include <common/compat/fcntl.h>
31 #include <common/sessiond-comm/sessiond-comm.h>
32
33 /* Commands for consumer */
34 enum lttng_consumer_command {
35 LTTNG_CONSUMER_ADD_CHANNEL,
36 LTTNG_CONSUMER_ADD_STREAM,
37 /* pause, delete, active depending on fd state */
38 LTTNG_CONSUMER_UPDATE_STREAM,
39 /* inform the consumer to quit when all fd has hang up */
40 LTTNG_CONSUMER_STOP,
41 LTTNG_CONSUMER_ADD_RELAYD_SOCKET,
42 /* Inform the consumer to kill a specific relayd connection */
43 LTTNG_CONSUMER_DESTROY_RELAYD,
44 /* Return to the sessiond if there is data pending for a session */
45 LTTNG_CONSUMER_DATA_PENDING,
46 };
47
48 /* State of each fd in consumer */
49 enum lttng_consumer_stream_state {
50 LTTNG_CONSUMER_ACTIVE_STREAM,
51 LTTNG_CONSUMER_PAUSE_STREAM,
52 LTTNG_CONSUMER_DELETE_STREAM,
53 };
54
55 enum lttng_consumer_type {
56 LTTNG_CONSUMER_UNKNOWN = 0,
57 LTTNG_CONSUMER_KERNEL,
58 LTTNG_CONSUMER64_UST,
59 LTTNG_CONSUMER32_UST,
60 };
61
62 enum consumer_endpoint_status {
63 CONSUMER_ENDPOINT_ACTIVE,
64 CONSUMER_ENDPOINT_INACTIVE,
65 };
66
67 struct lttng_consumer_channel {
68 struct lttng_ht_node_ulong node;
69 int key;
70 uint64_t max_sb_size; /* the subbuffer size for this channel */
71 int refcount; /* Number of streams referencing this channel */
72 /*
73 * The number of streams to receive initially. Used to guarantee that we do
74 * not destroy a channel before receiving all its associated streams.
75 */
76 unsigned int nb_init_streams;
77
78 /* For UST */
79 int shm_fd;
80 int wait_fd;
81 void *mmap_base;
82 size_t mmap_len;
83 struct lttng_ust_shm_handle *handle;
84 int wait_fd_is_copy;
85 int cpucount;
86 };
87
88 /* Forward declaration for UST. */
89 struct lttng_ust_lib_ring_buffer;
90
91 /*
92 * Internal representation of the streams, sessiond_key is used to identify
93 * uniquely a stream.
94 */
95 struct lttng_consumer_stream {
96 /* HT node used by the data_ht and metadata_ht */
97 struct lttng_ht_node_ulong node;
98 /* HT node used in consumer_data.stream_list_ht */
99 struct lttng_ht_node_ulong node_session_id;
100 struct lttng_consumer_channel *chan; /* associated channel */
101 /*
102 * key is the key used by the session daemon to refer to the
103 * object in the consumer daemon.
104 */
105 int key;
106 int shm_fd;
107 int wait_fd;
108 int out_fd; /* output file to write the data */
109 off_t out_fd_offset; /* write position in the output file descriptor */
110 char path_name[PATH_MAX]; /* tracefile name */
111 enum lttng_consumer_stream_state state;
112 size_t shm_len;
113 void *mmap_base;
114 size_t mmap_len;
115 enum lttng_event_output output; /* splice or mmap */
116 int shm_fd_is_copy;
117 int wait_fd_is_copy;
118 /* For UST */
119 struct lttng_ust_lib_ring_buffer *buf;
120 int cpu;
121 int data_read;
122 int hangup_flush_done;
123 /* UID/GID of the user owning the session to which stream belongs */
124 uid_t uid;
125 gid_t gid;
126 /* Network sequence number. Indicating on which relayd socket it goes. */
127 int net_seq_idx;
128 /* Identify if the stream is the metadata */
129 unsigned int metadata_flag;
130 /* Used when the stream is set for network streaming */
131 uint64_t relayd_stream_id;
132 /* Next sequence number to use for trace packet */
133 uint64_t next_net_seq_num;
134 /*
135 * Lock to use the stream FDs since they are used between threads.
136 *
137 * This is nested INSIDE the consumer_data lock.
138 * This is nested OUTSIDE consumer_relayd_sock_pair lock.
139 */
140 pthread_mutex_t lock;
141 /* Tracing session id */
142 uint64_t session_id;
143 /*
144 * Indicates if the stream end point is still active or not (network
145 * streaming or local file system). The thread "owning" the stream is
146 * handling this status and can be notified of a state change through the
147 * consumer data appropriate pipe.
148 */
149 enum consumer_endpoint_status endpoint_status;
150 };
151
152 /*
153 * Internal representation of a relayd socket pair.
154 */
155 struct consumer_relayd_sock_pair {
156 /* Network sequence number. */
157 int net_seq_idx;
158 /* Number of stream associated with this relayd */
159 unsigned int refcount;
160
161 /*
162 * This flag indicates whether or not we should destroy this object. The
163 * destruction should ONLY occurs when this flag is set and the refcount is
164 * set to zero.
165 */
166 unsigned int destroy_flag;
167
168 /*
169 * Mutex protecting the control socket to avoid out of order packets
170 * between threads sending data to the relayd. Since metadata data is sent
171 * over that socket, at least two sendmsg() are needed (header + data)
172 * creating a race for packets to overlap between threads using it.
173 *
174 * This is nested INSIDE the consumer_data lock.
175 * This is nested INSIDE the stream lock.
176 */
177 pthread_mutex_t ctrl_sock_mutex;
178
179 /* Control socket. Command and metadata are passed over it */
180 struct lttcomm_sock control_sock;
181
182 /*
183 * We don't need a mutex at this point since we only splice or write single
184 * large chunk of data with a header appended at the begining. Moreover,
185 * this socket is for now only used in a single thread.
186 */
187 struct lttcomm_sock data_sock;
188 struct lttng_ht_node_ulong node;
189
190 /* Session id on both sides for the sockets. */
191 uint64_t relayd_session_id;
192 uint64_t sessiond_session_id;
193 };
194
195 /*
196 * UST consumer local data to the program. One or more instance per
197 * process.
198 */
199 struct lttng_consumer_local_data {
200 /*
201 * Function to call when data is available on a buffer.
202 * Returns the number of bytes read, or negative error value.
203 */
204 ssize_t (*on_buffer_ready)(struct lttng_consumer_stream *stream,
205 struct lttng_consumer_local_data *ctx);
206 /*
207 * function to call when we receive a new channel, it receives a
208 * newly allocated channel, depending on the return code of this
209 * function, the new channel will be handled by the application
210 * or the library.
211 *
212 * Returns:
213 * > 0 (success, FD is kept by application)
214 * == 0 (success, FD is left to library)
215 * < 0 (error)
216 */
217 int (*on_recv_channel)(struct lttng_consumer_channel *channel);
218 /*
219 * function to call when we receive a new stream, it receives a
220 * newly allocated stream, depending on the return code of this
221 * function, the new stream will be handled by the application
222 * or the library.
223 *
224 * Returns:
225 * > 0 (success, FD is kept by application)
226 * == 0 (success, FD is left to library)
227 * < 0 (error)
228 */
229 int (*on_recv_stream)(struct lttng_consumer_stream *stream);
230 /*
231 * function to call when a stream is getting updated by the session
232 * daemon, this function receives the sessiond key and the new
233 * state, depending on the return code of this function the
234 * update of state for the stream is handled by the application
235 * or the library.
236 *
237 * Returns:
238 * > 0 (success, FD is kept by application)
239 * == 0 (success, FD is left to library)
240 * < 0 (error)
241 */
242 int (*on_update_stream)(int sessiond_key, uint32_t state);
243 /* socket to communicate errors with sessiond */
244 int consumer_error_socket;
245 /* socket to exchange commands with sessiond */
246 char *consumer_command_sock_path;
247 /* communication with splice */
248 int consumer_thread_pipe[2];
249 int consumer_splice_metadata_pipe[2];
250 /* Data stream poll thread pipe. To transfer data stream to the thread */
251 int consumer_data_pipe[2];
252 /* to let the signal handler wake up the fd receiver thread */
253 int consumer_should_quit[2];
254 /* Metadata poll thread pipe. Transfer metadata stream to it */
255 int consumer_metadata_pipe[2];
256 };
257
258 /*
259 * Library-level data. One instance per process.
260 */
261 struct lttng_consumer_global_data {
262 /*
263 * At this time, this lock is used to ensure coherence between the count
264 * and number of element in the hash table. It's also a protection for
265 * concurrent read/write between threads.
266 *
267 * This is nested OUTSIDE the stream lock.
268 * This is nested OUTSIDE the consumer_relayd_sock_pair lock.
269 */
270 pthread_mutex_t lock;
271
272 /*
273 * Number of streams in the data stream hash table declared outside.
274 * Protected by consumer_data.lock.
275 */
276 int stream_count;
277
278 /* Channel hash table protected by consumer_data.lock. */
279 struct lttng_ht *channel_ht;
280 /*
281 * Flag specifying if the local array of FDs needs update in the
282 * poll function. Protected by consumer_data.lock.
283 */
284 unsigned int need_update;
285 enum lttng_consumer_type type;
286
287 /*
288 * Relayd socket(s) hashtable indexed by network sequence number. Each
289 * stream has an index which associate the right relayd socket to use.
290 */
291 struct lttng_ht *relayd_ht;
292
293 /*
294 * This hash table contains all streams (metadata and data) indexed by
295 * session id. In other words, the ht is indexed by session id and each
296 * bucket contains the list of associated streams.
297 *
298 * This HT uses the "node_session_id" of the consumer stream.
299 */
300 struct lttng_ht *stream_list_ht;
301 };
302
303 /*
304 * Init consumer data structures.
305 */
306 extern void lttng_consumer_init(void);
307
308 /*
309 * Set the error socket for communication with a session daemon.
310 */
311 extern void lttng_consumer_set_error_sock(
312 struct lttng_consumer_local_data *ctx, int sock);
313
314 /*
315 * Set the command socket path for communication with a session daemon.
316 */
317 extern void lttng_consumer_set_command_sock_path(
318 struct lttng_consumer_local_data *ctx, char *sock);
319
320 /*
321 * Send return code to session daemon.
322 *
323 * Returns the return code of sendmsg : the number of bytes transmitted or -1
324 * on error.
325 */
326 extern int lttng_consumer_send_error(
327 struct lttng_consumer_local_data *ctx, int cmd);
328
329 /*
330 * Called from signal handler to ensure a clean exit.
331 */
332 extern void lttng_consumer_should_exit(
333 struct lttng_consumer_local_data *ctx);
334
335 /*
336 * Cleanup the daemon's socket on exit.
337 */
338 extern void lttng_consumer_cleanup(void);
339
340 /*
341 * Flush pending writes to trace output disk file.
342 */
343 extern void lttng_consumer_sync_trace_file(
344 struct lttng_consumer_stream *stream, off_t orig_offset);
345
346 /*
347 * Poll on the should_quit pipe and the command socket return -1 on error and
348 * should exit, 0 if data is available on the command socket
349 */
350 extern int lttng_consumer_poll_socket(struct pollfd *kconsumer_sockpoll);
351
352 extern struct lttng_consumer_stream *consumer_allocate_stream(
353 int channel_key, int stream_key,
354 int shm_fd, int wait_fd,
355 enum lttng_consumer_stream_state state,
356 uint64_t mmap_len,
357 enum lttng_event_output output,
358 const char *path_name,
359 uid_t uid,
360 gid_t gid,
361 int net_index,
362 int metadata_flag,
363 uint64_t session_id,
364 int *alloc_ret);
365 extern void consumer_del_stream(struct lttng_consumer_stream *stream,
366 struct lttng_ht *ht);
367 extern void consumer_del_metadata_stream(struct lttng_consumer_stream *stream,
368 struct lttng_ht *ht);
369 extern void consumer_del_channel(struct lttng_consumer_channel *channel);
370 extern struct lttng_consumer_channel *consumer_allocate_channel(
371 int channel_key,
372 int shm_fd, int wait_fd,
373 uint64_t mmap_len,
374 uint64_t max_sb_size,
375 unsigned int nb_init_streams);
376 int consumer_add_channel(struct lttng_consumer_channel *channel);
377
378 /* lttng-relayd consumer command */
379 struct consumer_relayd_sock_pair *consumer_allocate_relayd_sock_pair(
380 int net_seq_idx);
381 struct consumer_relayd_sock_pair *consumer_find_relayd(int key);
382 int consumer_handle_stream_before_relayd(struct lttng_consumer_stream *stream,
383 size_t data_size);
384 void consumer_steal_stream_key(int key, struct lttng_ht *ht);
385
386 extern struct lttng_consumer_local_data *lttng_consumer_create(
387 enum lttng_consumer_type type,
388 ssize_t (*buffer_ready)(struct lttng_consumer_stream *stream,
389 struct lttng_consumer_local_data *ctx),
390 int (*recv_channel)(struct lttng_consumer_channel *channel),
391 int (*recv_stream)(struct lttng_consumer_stream *stream),
392 int (*update_stream)(int sessiond_key, uint32_t state));
393 extern void lttng_consumer_destroy(struct lttng_consumer_local_data *ctx);
394 extern ssize_t lttng_consumer_on_read_subbuffer_mmap(
395 struct lttng_consumer_local_data *ctx,
396 struct lttng_consumer_stream *stream, unsigned long len,
397 unsigned long padding);
398 extern ssize_t lttng_consumer_on_read_subbuffer_splice(
399 struct lttng_consumer_local_data *ctx,
400 struct lttng_consumer_stream *stream, unsigned long len,
401 unsigned long padding);
402 extern int lttng_consumer_take_snapshot(struct lttng_consumer_local_data *ctx,
403 struct lttng_consumer_stream *stream);
404 extern int lttng_consumer_get_produced_snapshot(
405 struct lttng_consumer_local_data *ctx,
406 struct lttng_consumer_stream *stream,
407 unsigned long *pos);
408 extern void *consumer_thread_metadata_poll(void *data);
409 extern void *consumer_thread_data_poll(void *data);
410 extern void *consumer_thread_sessiond_poll(void *data);
411 extern int lttng_consumer_recv_cmd(struct lttng_consumer_local_data *ctx,
412 int sock, struct pollfd *consumer_sockpoll);
413
414 ssize_t lttng_consumer_read_subbuffer(struct lttng_consumer_stream *stream,
415 struct lttng_consumer_local_data *ctx);
416 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream *stream);
417 int consumer_add_relayd_socket(int net_seq_idx, int sock_type,
418 struct lttng_consumer_local_data *ctx, int sock,
419 struct pollfd *consumer_sockpoll, struct lttcomm_sock *relayd_sock,
420 unsigned int sessiond_id);
421 void consumer_flag_relayd_for_destroy(
422 struct consumer_relayd_sock_pair *relayd);
423 int consumer_data_pending(uint64_t id);
424 int consumer_send_status_msg(int sock, int ret_code);
425
426 #endif /* LIB_CONSUMER_H */
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