2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License, version 2 only,
6 * as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 #ifndef _LTT_SESSION_H
19 #define _LTT_SESSION_H
23 #include <urcu/list.h>
25 #include <common/hashtable/hashtable.h>
26 #include <common/dynamic-array.h>
27 #include <lttng/rotation.h>
28 #include <lttng/location.h>
29 #include <lttng/lttng-error.h>
32 #include "trace-kernel.h"
35 struct ltt_ust_session
;
37 typedef void (*ltt_session_destroy_notifier
)(const struct ltt_session
*session
,
41 * Tracing session list
43 * Statically declared in session.c and can be accessed by using
44 * session_get_list() function that returns the pointer to the list.
46 struct ltt_session_list
{
48 * This lock protects any read/write access to the list and
49 * next_uuid. All public functions in session.c acquire this
50 * lock and release it before returning. If none of those
51 * functions are used, the lock MUST be acquired in order to
52 * iterate or/and do any actions on that list.
56 * This condition variable is signaled on every removal from
59 pthread_cond_t removal_cond
;
62 * Session unique ID generator. The session list lock MUST be
63 * upon update and read of this counter.
67 /* Linked list head */
68 struct cds_list_head head
;
72 * This data structure contains information needed to identify a tracing
73 * session for both LTTng and UST.
77 bool has_auto_generated_name
;
78 bool name_contains_creation_time
;
79 char hostname
[HOST_NAME_MAX
]; /* Local hostname. */
81 struct ltt_kernel_session
*kernel_session
;
82 struct ltt_ust_session
*ust_session
;
85 * Protect any read/write on this session data structure. This lock must be
86 * acquired *before* using any public functions declared below. Use
87 * session_lock() and session_unlock() for that.
90 struct cds_list_head list
;
91 uint64_t id
; /* session unique identifier */
92 /* Indicates if the session has been added to the session list and ht.*/
94 /* Indicates if a destroy command has been applied to this session. */
96 /* UID/GID of the user owning the session */
100 * Network session handle. A value of 0 means that there is no remote
101 * session established.
105 * This consumer is only set when the create_session_uri call is made.
106 * This contains the temporary information for a consumer output. Upon
107 * creation of the UST or kernel session, this consumer, if available, is
108 * copied into those sessions.
110 struct consumer_output
*consumer
;
112 * Indicates whether or not the user has specified an output directory
113 * or if it was configured using the default configuration.
115 bool has_user_specified_directory
;
116 /* Did at least ONE start command has been triggered?. */
117 unsigned int has_been_started
:1;
119 * Is the session active? Start trace command sets this to 1 and the stop
120 * command reset it to 0.
122 unsigned int active
:1;
124 /* Snapshot representation in a session. */
125 struct snapshot snapshot
;
126 /* Indicate if the session has to output the traces or not. */
127 unsigned int output_traces
;
129 * This session is in snapshot mode. This means that channels enabled
130 * will be set in overwrite mode by default and must be in mmap
131 * output mode. Note that snapshots can be taken on a session that
132 * is not in "snapshot_mode". This parameter only affects channel
135 unsigned int snapshot_mode
;
137 * A session that has channels that don't use 'mmap' output can't be
138 * used to capture snapshots. This is set to true whenever a
139 * 'splice' kernel channel is enabled.
141 bool has_non_mmap_channel
;
143 * Timer set when the session is created for live reading.
145 unsigned int live_timer
;
147 * Path where to keep the shared memory files.
149 char shm_path
[PATH_MAX
];
151 * Node in ltt_sessions_ht_by_id.
153 struct lttng_ht_node_u64 node
;
155 * Timer to check periodically if a relay and/or consumer has completed
158 bool rotation_pending_check_timer_enabled
;
159 timer_t rotation_pending_check_timer
;
160 /* Timer to periodically rotate a session. */
161 bool rotation_schedule_timer_enabled
;
162 timer_t rotation_schedule_timer
;
163 /* Value for periodic rotations, 0 if disabled. */
164 uint64_t rotate_timer_period
;
165 /* Value for size-based rotations, 0 if disabled. */
166 uint64_t rotate_size
;
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
170 * know if a rotation occurred since the last stop to rename the current
173 bool rotated_after_last_stop
;
175 * Condition and trigger for size-based rotations.
177 struct lttng_condition
*rotate_condition
;
178 struct lttng_trigger
*rotate_trigger
;
179 LTTNG_OPTIONAL(uint64_t) most_recent_chunk_id
;
180 struct lttng_trace_chunk
*current_trace_chunk
;
181 struct lttng_trace_chunk
*chunk_being_archived
;
182 /* Current state of a rotation. */
183 enum lttng_rotation_state rotation_state
;
185 char *last_archived_chunk_name
;
186 LTTNG_OPTIONAL(uint64_t) last_archived_chunk_id
;
187 struct lttng_dynamic_array destroy_notifiers
;
188 /* Session base path override. Set non-null. */
193 enum lttng_error_code
session_create(const char *name
, uid_t uid
, gid_t gid
,
194 const char *base_path
, struct ltt_session
**out_session
);
195 void session_lock(struct ltt_session
*session
);
196 void session_lock_list(void);
197 int session_trylock_list(void);
198 void session_unlock(struct ltt_session
*session
);
199 void session_unlock_list(void);
201 void session_destroy(struct ltt_session
*session
);
202 int session_add_destroy_notifier(struct ltt_session
*session
,
203 ltt_session_destroy_notifier notifier
, void *user_data
);
205 bool session_get(struct ltt_session
*session
);
206 void session_put(struct ltt_session
*session
);
208 enum consumer_dst_type
session_get_consumer_destination_type(
209 const struct ltt_session
*session
);
210 const char *session_get_net_consumer_hostname(
211 const struct ltt_session
*session
);
212 void session_get_net_consumer_ports(
213 const struct ltt_session
*session
,
214 uint16_t *control_port
, uint16_t *data_port
);
215 struct lttng_trace_archive_location
*session_get_trace_archive_location(
216 const struct ltt_session
*session
);
218 struct ltt_session
*session_find_by_name(const char *name
);
219 struct ltt_session
*session_find_by_id(uint64_t id
);
221 struct ltt_session_list
*session_get_list(void);
222 void session_list_wait_empty(void);
224 int session_access_ok(struct ltt_session
*session
, uid_t uid
, gid_t gid
);
226 int session_reset_rotation_state(struct ltt_session
*session
,
227 enum lttng_rotation_state result
);
229 /* Create a new trace chunk object from the session's configuration. */
230 struct lttng_trace_chunk
*session_create_new_trace_chunk(
231 const struct ltt_session
*session
,
232 const struct consumer_output
*consumer_output_override
,
233 const char *session_base_path_override
,
234 const char *chunk_name_override
);
237 * Set `new_trace_chunk` as the session's current trace chunk. A reference
238 * to `new_trace_chunk` is acquired by the session. The chunk is created
239 * on remote peers (consumer and relay daemons).
241 * A reference to the session's current trace chunk is returned through
242 * `current_session_trace_chunk` on success.
244 int session_set_trace_chunk(struct ltt_session
*session
,
245 struct lttng_trace_chunk
*new_trace_chunk
,
246 struct lttng_trace_chunk
**current_session_trace_chunk
);
249 * Close a chunk on the remote peers of a session. Has no effect on the
250 * ltt_session itself.
252 int session_close_trace_chunk(const struct ltt_session
*session
,
253 struct lttng_trace_chunk
*trace_chunk
,
254 const enum lttng_trace_chunk_command_type
*close_command
);
256 bool session_output_supports_trace_chunks(const struct ltt_session
*session
);
258 #endif /* _LTT_SESSION_H */