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