Commit | Line | Data |
---|---|---|
91d76f53 | 1 | /* |
21cf9b6b | 2 | * Copyright (C) 2011 EfficiOS Inc. |
5b74c7b1 | 3 | * |
ab5be9fa | 4 | * SPDX-License-Identifier: GPL-2.0-only |
5b74c7b1 | 5 | * |
5b74c7b1 DG |
6 | */ |
7 | ||
8 | #ifndef _LTT_SESSION_H | |
9 | #define _LTT_SESSION_H | |
10 | ||
73184835 | 11 | #include <limits.h> |
5c408ad8 | 12 | #include <stdbool.h> |
20fe2104 | 13 | #include <urcu/list.h> |
d4a2a84a | 14 | |
c9e313bc SM |
15 | #include <common/hashtable/hashtable.hpp> |
16 | #include <common/dynamic-array.hpp> | |
e99e3664 | 17 | #include <common/make-unique-wrapper.hpp> |
db66e574 | 18 | #include <lttng/rotation.h> |
5d65beab | 19 | #include <lttng/location.h> |
82b69413 | 20 | #include <lttng/lttng-error.h> |
6dc3064a | 21 | |
c9e313bc SM |
22 | #include "snapshot.hpp" |
23 | #include "trace-kernel.hpp" | |
24 | #include "consumer.hpp" | |
7972aab2 | 25 | |
3130a40c JG |
26 | #define ASSERT_SESSION_LIST_LOCKED() LTTNG_ASSERT(session_trylock_list()) |
27 | ||
7972aab2 | 28 | struct ltt_ust_session; |
00187dd4 | 29 | |
3e3665b8 JG |
30 | typedef void (*ltt_session_destroy_notifier)(const struct ltt_session *session, |
31 | void *user_data); | |
ccbdaca4 MD |
32 | typedef void (*ltt_session_clear_notifier)(const struct ltt_session *session, |
33 | void *user_data); | |
3e3665b8 | 34 | |
e99e3664 JG |
35 | namespace lttng { |
36 | namespace sessiond { | |
37 | namespace details { | |
38 | void locked_session_release(ltt_session *session); | |
39 | } /* namespace details */ | |
40 | } /* namespace sessiond */ | |
41 | } /* namespace lttng */ | |
42 | ||
b5541356 DG |
43 | /* |
44 | * Tracing session list | |
45 | * | |
46 | * Statically declared in session.c and can be accessed by using | |
54d01ffb | 47 | * session_get_list() function that returns the pointer to the list. |
b5541356 | 48 | */ |
5b74c7b1 | 49 | struct ltt_session_list { |
b5541356 | 50 | /* |
a24f7994 MD |
51 | * This lock protects any read/write access to the list and |
52 | * next_uuid. All public functions in session.c acquire this | |
53 | * lock and release it before returning. If none of those | |
54 | * functions are used, the lock MUST be acquired in order to | |
55 | * iterate or/and do any actions on that list. | |
b5541356 DG |
56 | */ |
57 | pthread_mutex_t lock; | |
99d688f2 JG |
58 | /* |
59 | * This condition variable is signaled on every removal from | |
60 | * the session list. | |
61 | */ | |
62 | pthread_cond_t removal_cond; | |
6c9cc2ab | 63 | |
b5541356 | 64 | /* |
a24f7994 MD |
65 | * Session unique ID generator. The session list lock MUST be |
66 | * upon update and read of this counter. | |
b5541356 | 67 | */ |
d022620a | 68 | uint64_t next_uuid; |
6c9cc2ab DG |
69 | |
70 | /* Linked list head */ | |
5b74c7b1 DG |
71 | struct cds_list_head head; |
72 | }; | |
73 | ||
b5541356 DG |
74 | /* |
75 | * This data structure contains information needed to identify a tracing | |
76 | * session for both LTTng and UST. | |
5b74c7b1 DG |
77 | */ |
78 | struct ltt_session { | |
e99e3664 JG |
79 | using id_t = uint64_t; |
80 | using locked_ptr = std::unique_ptr<ltt_session, | |
81 | lttng::details::create_unique_class<ltt_session, | |
82 | lttng::sessiond::details::locked_session_release>::deleter>; | |
83 | using sptr = std::shared_ptr<ltt_session>; | |
84 | ||
74babd95 | 85 | char name[NAME_MAX]; |
b178f53e | 86 | bool has_auto_generated_name; |
46ef2188 | 87 | bool name_contains_creation_time; |
32aef76c | 88 | char hostname[LTTNG_HOST_NAME_MAX]; /* Local hostname. */ |
ecd1a12f MD |
89 | /* Path of the last closed chunk. */ |
90 | char last_chunk_path[LTTNG_PATH_MAX]; | |
b178f53e | 91 | time_t creation_time; |
20fe2104 | 92 | struct ltt_kernel_session *kernel_session; |
f6a9efaa | 93 | struct ltt_ust_session *ust_session; |
e32d7f27 | 94 | struct urcu_ref ref; |
b5541356 DG |
95 | /* |
96 | * Protect any read/write on this session data structure. This lock must be | |
97 | * acquired *before* using any public functions declared below. Use | |
54d01ffb | 98 | * session_lock() and session_unlock() for that. |
b5541356 DG |
99 | */ |
100 | pthread_mutex_t lock; | |
101 | struct cds_list_head list; | |
e99e3664 JG |
102 | /* session unique identifier */ |
103 | id_t id; | |
f4cc5e83 JG |
104 | /* Indicates if the session has been added to the session list and ht.*/ |
105 | bool published; | |
e32d7f27 JG |
106 | /* Indicates if a destroy command has been applied to this session. */ |
107 | bool destroyed; | |
6df2e2c9 MD |
108 | /* UID/GID of the user owning the session */ |
109 | uid_t uid; | |
110 | gid_t gid; | |
00e2e675 DG |
111 | /* |
112 | * Network session handle. A value of 0 means that there is no remote | |
113 | * session established. | |
114 | */ | |
115 | uint64_t net_handle; | |
116 | /* | |
117 | * This consumer is only set when the create_session_uri call is made. | |
118 | * This contains the temporary information for a consumer output. Upon | |
119 | * creation of the UST or kernel session, this consumer, if available, is | |
120 | * copied into those sessions. | |
121 | */ | |
122 | struct consumer_output *consumer; | |
b178f53e JG |
123 | /* |
124 | * Indicates whether or not the user has specified an output directory | |
125 | * or if it was configured using the default configuration. | |
126 | */ | |
127 | bool has_user_specified_directory; | |
8382cf6f DG |
128 | /* Did at least ONE start command has been triggered?. */ |
129 | unsigned int has_been_started:1; | |
130 | /* | |
131 | * Is the session active? Start trace command sets this to 1 and the stop | |
132 | * command reset it to 0. | |
133 | */ | |
134 | unsigned int active:1; | |
6dc3064a DG |
135 | |
136 | /* Snapshot representation in a session. */ | |
137 | struct snapshot snapshot; | |
138 | /* Indicate if the session has to output the traces or not. */ | |
139 | unsigned int output_traces; | |
27babd3a | 140 | /* |
92fe5ca1 JG |
141 | * This session is in snapshot mode. This means that channels enabled |
142 | * will be set in overwrite mode by default and must be in mmap | |
143 | * output mode. Note that snapshots can be taken on a session that | |
144 | * is not in "snapshot_mode". This parameter only affects channel | |
145 | * creation defaults. | |
27babd3a DG |
146 | */ |
147 | unsigned int snapshot_mode; | |
54213acc JG |
148 | /* |
149 | * A session that has channels that don't use 'mmap' output can't be | |
150 | * used to capture snapshots. This is set to true whenever a | |
151 | * 'splice' kernel channel is enabled. | |
152 | */ | |
153 | bool has_non_mmap_channel; | |
ecc48a90 JD |
154 | /* |
155 | * Timer set when the session is created for live reading. | |
156 | */ | |
d98ad589 | 157 | unsigned int live_timer; |
d7ba1388 MD |
158 | /* |
159 | * Path where to keep the shared memory files. | |
160 | */ | |
161 | char shm_path[PATH_MAX]; | |
23324029 JD |
162 | /* |
163 | * Node in ltt_sessions_ht_by_id. | |
164 | */ | |
165 | struct lttng_ht_node_u64 node; | |
e1bbf989 JR |
166 | /* |
167 | * Node in ltt_sessions_ht_by_name. | |
168 | */ | |
169 | struct lttng_ht_node_str node_by_name; | |
d88744a4 | 170 | /* |
92816cc3 JG |
171 | * Timer to check periodically if a relay and/or consumer has completed |
172 | * the last rotation. | |
d88744a4 | 173 | */ |
92816cc3 JG |
174 | bool rotation_pending_check_timer_enabled; |
175 | timer_t rotation_pending_check_timer; | |
259c2674 | 176 | /* Timer to periodically rotate a session. */ |
92816cc3 JG |
177 | bool rotation_schedule_timer_enabled; |
178 | timer_t rotation_schedule_timer; | |
66ea93b1 | 179 | /* Value for periodic rotations, 0 if disabled. */ |
259c2674 | 180 | uint64_t rotate_timer_period; |
66ea93b1 | 181 | /* Value for size-based rotations, 0 if disabled. */ |
259c2674 | 182 | uint64_t rotate_size; |
5c408ad8 JD |
183 | /* |
184 | * Keep a state if this session was rotated after the last stop command. | |
185 | * We only allow one rotation after a stop. At destroy, we also need to | |
a9577b76 | 186 | * know if a rotation occurred since the last stop to rename the current |
a2b988e2 MD |
187 | * chunk. After a stop followed by rotate, all subsequent clear |
188 | * (without prior start) will succeed, but will be effect-less. | |
5c408ad8 JD |
189 | */ |
190 | bool rotated_after_last_stop; | |
b02f5986 MD |
191 | /* |
192 | * Track whether the session was cleared after last stop. All subsequent | |
193 | * clear (without prior start) will succeed, but will be effect-less. A | |
194 | * subsequent rotate (without prior start) will return an error. | |
195 | */ | |
196 | bool cleared_after_last_stop; | |
a7ceb342 MD |
197 | /* |
198 | * True if the session has had an explicit non-quiet rotation. | |
199 | */ | |
200 | bool rotated; | |
90936dcf | 201 | /* |
c08136a3 | 202 | * Trigger for size-based rotations. |
90936dcf | 203 | */ |
90936dcf | 204 | struct lttng_trigger *rotate_trigger; |
d2956687 | 205 | LTTNG_OPTIONAL(uint64_t) most_recent_chunk_id; |
82b69413 | 206 | struct lttng_trace_chunk *current_trace_chunk; |
d2956687 JG |
207 | struct lttng_trace_chunk *chunk_being_archived; |
208 | /* Current state of a rotation. */ | |
209 | enum lttng_rotation_state rotation_state; | |
7fdbed1c | 210 | bool quiet_rotation; |
d2956687 JG |
211 | char *last_archived_chunk_name; |
212 | LTTNG_OPTIONAL(uint64_t) last_archived_chunk_id; | |
3e3665b8 | 213 | struct lttng_dynamic_array destroy_notifiers; |
ccbdaca4 | 214 | struct lttng_dynamic_array clear_notifiers; |
6fa5fe7c MD |
215 | /* Session base path override. Set non-null. */ |
216 | char *base_path; | |
5b74c7b1 DG |
217 | }; |
218 | ||
b178f53e | 219 | enum lttng_error_code session_create(const char *name, uid_t uid, gid_t gid, |
e3876bf0 | 220 | struct ltt_session **out_session); |
54d01ffb | 221 | void session_lock(struct ltt_session *session); |
733c9165 JG |
222 | void session_unlock(struct ltt_session *session); |
223 | ||
224 | /* | |
225 | * The session list lock covers more ground than its name implies. While | |
226 | * it does protect against concurent mutations of the session list, it is | |
227 | * also used as a multi-session lock when synchronizing newly-registered | |
228 | * 'user space tracer' and 'agent' applications. | |
229 | * | |
9b7cbebd | 230 | * In other words, it prevents tracer configurations from changing while they |
733c9165 JG |
231 | * are being transmitted to the various applications. |
232 | */ | |
54d01ffb | 233 | void session_lock_list(void); |
71e0a100 | 234 | int session_trylock_list(void); |
54d01ffb | 235 | void session_unlock_list(void); |
6c9cc2ab | 236 | |
e32d7f27 | 237 | void session_destroy(struct ltt_session *session); |
3e3665b8 JG |
238 | int session_add_destroy_notifier(struct ltt_session *session, |
239 | ltt_session_destroy_notifier notifier, void *user_data); | |
e32d7f27 | 240 | |
ccbdaca4 MD |
241 | int session_add_clear_notifier(struct ltt_session *session, |
242 | ltt_session_clear_notifier notifier, void *user_data); | |
243 | void session_notify_clear(struct ltt_session *session); | |
244 | ||
e32d7f27 JG |
245 | bool session_get(struct ltt_session *session); |
246 | void session_put(struct ltt_session *session); | |
247 | ||
dd73d57b JG |
248 | enum consumer_dst_type session_get_consumer_destination_type( |
249 | const struct ltt_session *session); | |
250 | const char *session_get_net_consumer_hostname( | |
251 | const struct ltt_session *session); | |
252 | void session_get_net_consumer_ports( | |
253 | const struct ltt_session *session, | |
254 | uint16_t *control_port, uint16_t *data_port); | |
5d65beab | 255 | struct lttng_trace_archive_location *session_get_trace_archive_location( |
3e3665b8 | 256 | const struct ltt_session *session); |
dd73d57b | 257 | |
58a1a227 | 258 | struct ltt_session *session_find_by_name(const char *name); |
e99e3664 | 259 | struct ltt_session *session_find_by_id(ltt_session::id_t id); |
99d688f2 | 260 | |
54d01ffb | 261 | struct ltt_session_list *session_get_list(void); |
99d688f2 | 262 | void session_list_wait_empty(void); |
5b74c7b1 | 263 | |
d7b377ed | 264 | bool session_access_ok(struct ltt_session *session, uid_t uid); |
2f77fc4b | 265 | |
2961f09e JG |
266 | int session_reset_rotation_state(struct ltt_session *session, |
267 | enum lttng_rotation_state result); | |
268 | ||
d2956687 JG |
269 | /* Create a new trace chunk object from the session's configuration. */ |
270 | struct lttng_trace_chunk *session_create_new_trace_chunk( | |
348a81dc JG |
271 | const struct ltt_session *session, |
272 | const struct consumer_output *consumer_output_override, | |
82b69413 JG |
273 | const char *session_base_path_override, |
274 | const char *chunk_name_override); | |
d2956687 JG |
275 | |
276 | /* | |
277 | * Set `new_trace_chunk` as the session's current trace chunk. A reference | |
278 | * to `new_trace_chunk` is acquired by the session. The chunk is created | |
279 | * on remote peers (consumer and relay daemons). | |
280 | * | |
281 | * A reference to the session's current trace chunk is returned through | |
282 | * `current_session_trace_chunk` on success. | |
283 | */ | |
82b69413 | 284 | int session_set_trace_chunk(struct ltt_session *session, |
d2956687 JG |
285 | struct lttng_trace_chunk *new_trace_chunk, |
286 | struct lttng_trace_chunk **current_session_trace_chunk); | |
287 | ||
288 | /* | |
289 | * Close a chunk on the remote peers of a session. Has no effect on the | |
290 | * ltt_session itself. | |
291 | */ | |
343defc2 | 292 | int session_close_trace_chunk(struct ltt_session *session, |
bbc4768c | 293 | struct lttng_trace_chunk *trace_chunk, |
343defc2 | 294 | enum lttng_trace_chunk_command_type close_command, |
ecd1a12f | 295 | char *path); |
82b69413 | 296 | |
04ed9e10 JG |
297 | /* Open a packet in all channels of a given session. */ |
298 | enum lttng_error_code session_open_packets(struct ltt_session *session); | |
299 | ||
e2b6b28e JG |
300 | bool session_output_supports_trace_chunks(const struct ltt_session *session); |
301 | ||
e1bbf989 JR |
302 | /* |
303 | * Sample the id of a session looked up via its name. | |
304 | * Here the term "sampling" hint the caller that this return the id at a given | |
305 | * point in time with no guarantee that the session for which the id was | |
306 | * sampled still exist at that point. | |
307 | * | |
308 | * Return 0 when the session is not found, | |
309 | * Return 1 when the session is found and set `id`. | |
310 | */ | |
311 | bool sample_session_id_by_name(const char *name, uint64_t *id); | |
312 | ||
e99e3664 JG |
313 | namespace lttng { |
314 | namespace sessiond { | |
315 | ||
316 | /* | |
317 | * Session list lock must be acquired by the caller. | |
318 | * The caller must not keep the ownership of the returned locked session | |
319 | * for longer than strictly necessary. If your intention is to acquire | |
320 | * a reference to an ltt_session, see `find_session_by_id()`. | |
321 | */ | |
322 | ltt_session::locked_ptr find_locked_session_by_id(ltt_session::id_t id); | |
323 | ||
324 | /* | |
325 | * Session list lock must be acquired by the caller. | |
326 | * The caller must not keep the ownership of the returned locked session | |
327 | * for longer than strictly necessary. If your intention is to acquire | |
328 | * a reference to an ltt_session, see `find_session_by_id()`. | |
329 | */ | |
330 | ltt_session::sptr find_session_by_id(ltt_session::id_t id); | |
331 | ||
332 | } /* namespace sessiond */ | |
333 | } /* namespace lttng */ | |
334 | ||
5b74c7b1 | 335 | #endif /* _LTT_SESSION_H */ |