Commit | Line | Data |
---|---|---|
f2b3ef9f JG |
1 | /* |
2 | * Copyright (C) 2020 Jérémie Galarneau <jeremie.galarneau@efficios.com> | |
3 | * | |
4 | * SPDX-License-Identifier: GPL-2.0-only | |
5 | * | |
6 | */ | |
7 | ||
8 | #include "action-executor.h" | |
9 | #include "cmd.h" | |
10 | #include "health-sessiond.h" | |
11 | #include "lttng-sessiond.h" | |
12 | #include "notification-thread-internal.h" | |
13 | #include "session.h" | |
14 | #include "thread.h" | |
72365501 | 15 | #include <common/dynamic-array.h> |
f2b3ef9f JG |
16 | #include <common/macros.h> |
17 | #include <common/optional.h> | |
18 | #include <lttng/action/action-internal.h> | |
ad63a966 JR |
19 | #include <lttng/action/list-internal.h> |
20 | #include <lttng/action/list.h> | |
2af3b9c9 | 21 | #include <lttng/action/notify-internal.h> |
f2b3ef9f JG |
22 | #include <lttng/action/notify.h> |
23 | #include <lttng/action/rotate-session.h> | |
24 | #include <lttng/action/snapshot-session.h> | |
25 | #include <lttng/action/start-session.h> | |
26 | #include <lttng/action/stop-session.h> | |
27 | #include <lttng/condition/evaluation.h> | |
670a26e4 | 28 | #include <lttng/condition/event-rule-matches-internal.h> |
f2b3ef9f JG |
29 | #include <lttng/lttng-error.h> |
30 | #include <lttng/trigger/trigger-internal.h> | |
31 | #include <pthread.h> | |
32 | #include <stdbool.h> | |
33 | #include <stddef.h> | |
34 | #include <urcu/list.h> | |
35 | ||
36 | #define THREAD_NAME "Action Executor" | |
37 | #define MAX_QUEUED_WORK_COUNT 8192 | |
38 | ||
72365501 JR |
39 | /* |
40 | * A work item is composed of a dynamic array of sub-items which | |
41 | * represent a flattened, and augmented, version of a trigger's actions. | |
42 | * | |
43 | * We cannot rely solely on the trigger's actions since each action can have an | |
44 | * execution context we need to comply with. | |
45 | * | |
46 | * The notion of execution context is required since for some actions the | |
47 | * associated object are referenced by name and not by id. This can lead to | |
48 | * a number of ambiguities when executing an action work item. | |
49 | * | |
50 | * For example, let's take a simple trigger such as: | |
51 | * - condition: ust event a | |
52 | * - action: start session S | |
53 | * | |
54 | * At time T, session S exists. | |
55 | * At T + 1, the event A is hit. | |
56 | * At T + 2, the tracer event notification is received and the work item is | |
57 | * queued. Here session S have an id of 1. | |
58 | * At T + 3, the session S is destroyed and a new session S is created, with a | |
59 | * resulting id of 200. | |
60 | * At T +4, the work item is popped from the queue and begin execution and will | |
61 | * start session S with an id of 200 instead of the session S id 1 that was | |
62 | * present at the queuing phase. | |
63 | * | |
64 | * The context to be respected is the one when the work item is queued. If the | |
65 | * execution context is not the same at the moment of execution, we skip the | |
66 | * execution of that sub-item. | |
67 | * | |
68 | * It is the same policy in regards to the validity of the associated | |
69 | * trigger object at the moment of execution, if the trigger is found to be | |
70 | * unregistered, the execution is skipped. | |
71 | */ | |
72 | ||
f2b3ef9f JG |
73 | struct action_work_item { |
74 | uint64_t id; | |
72365501 JR |
75 | |
76 | /* | |
77 | * The actions to be executed with their respective execution context. | |
78 | * See struct `action_work_subitem`. | |
79 | */ | |
be65f802 | 80 | struct lttng_dynamic_array subitems; |
72365501 JR |
81 | |
82 | /* Execution context data */ | |
f2b3ef9f JG |
83 | struct lttng_trigger *trigger; |
84 | struct lttng_evaluation *evaluation; | |
85 | struct notification_client_list *client_list; | |
86 | LTTNG_OPTIONAL(struct lttng_credentials) object_creds; | |
87 | struct cds_list_head list_node; | |
88 | }; | |
89 | ||
72365501 JR |
90 | struct action_work_subitem { |
91 | struct lttng_action *action; | |
92 | struct { | |
93 | /* Used by actions targeting a session. */ | |
94 | LTTNG_OPTIONAL(uint64_t) session_id; | |
95 | } context; | |
96 | }; | |
97 | ||
f2b3ef9f JG |
98 | struct action_executor { |
99 | struct lttng_thread *thread; | |
100 | struct notification_thread_handle *notification_thread_handle; | |
101 | struct { | |
102 | uint64_t pending_count; | |
103 | struct cds_list_head list; | |
104 | pthread_cond_t cond; | |
105 | pthread_mutex_t lock; | |
106 | } work; | |
107 | bool should_quit; | |
108 | uint64_t next_work_item_id; | |
109 | }; | |
110 | ||
111 | /* | |
112 | * Only return non-zero on a fatal error that should shut down the action | |
113 | * executor. | |
114 | */ | |
115 | typedef int (*action_executor_handler)(struct action_executor *executor, | |
116 | const struct action_work_item *, | |
72365501 | 117 | struct action_work_subitem *item); |
f2b3ef9f JG |
118 | |
119 | static int action_executor_notify_handler(struct action_executor *executor, | |
120 | const struct action_work_item *, | |
72365501 | 121 | struct action_work_subitem *); |
2d57482c JR |
122 | static int action_executor_start_session_handler( |
123 | struct action_executor *executor, | |
f2b3ef9f | 124 | const struct action_work_item *, |
72365501 | 125 | struct action_work_subitem *); |
2d57482c JR |
126 | static int action_executor_stop_session_handler( |
127 | struct action_executor *executor, | |
f2b3ef9f | 128 | const struct action_work_item *, |
72365501 | 129 | struct action_work_subitem *); |
2d57482c JR |
130 | static int action_executor_rotate_session_handler( |
131 | struct action_executor *executor, | |
f2b3ef9f | 132 | const struct action_work_item *, |
72365501 | 133 | struct action_work_subitem *); |
2d57482c JR |
134 | static int action_executor_snapshot_session_handler( |
135 | struct action_executor *executor, | |
f2b3ef9f | 136 | const struct action_work_item *, |
72365501 | 137 | struct action_work_subitem *); |
7c2fae7c | 138 | static int action_executor_list_handler(struct action_executor *executor, |
f2b3ef9f | 139 | const struct action_work_item *, |
72365501 | 140 | struct action_work_subitem *); |
f2b3ef9f JG |
141 | static int action_executor_generic_handler(struct action_executor *executor, |
142 | const struct action_work_item *, | |
72365501 | 143 | struct action_work_subitem *); |
f2b3ef9f JG |
144 | |
145 | static const action_executor_handler action_executors[] = { | |
7966af57 SM |
146 | action_executor_notify_handler, |
147 | action_executor_start_session_handler, | |
148 | action_executor_stop_session_handler, | |
149 | action_executor_rotate_session_handler, | |
150 | action_executor_snapshot_session_handler, | |
151 | action_executor_list_handler, | |
f2b3ef9f JG |
152 | }; |
153 | ||
72365501 JR |
154 | /* Forward declaration */ |
155 | static int add_action_to_subitem_array(struct lttng_action *action, | |
156 | struct lttng_dynamic_array *subitems); | |
157 | ||
158 | static int populate_subitem_array_from_trigger(struct lttng_trigger *trigger, | |
159 | struct lttng_dynamic_array *subitems); | |
160 | ||
161 | static void action_work_subitem_destructor(void *element) | |
162 | { | |
7966af57 | 163 | struct action_work_subitem *subitem = (action_work_subitem *) element; |
72365501 JR |
164 | |
165 | lttng_action_put(subitem->action); | |
166 | } | |
167 | ||
f2b3ef9f JG |
168 | static const char *get_action_name(const struct lttng_action *action) |
169 | { | |
0e43bcbf JG |
170 | const enum lttng_action_type action_type = lttng_action_get_type(action); |
171 | ||
a0377dfe | 172 | LTTNG_ASSERT(action_type != LTTNG_ACTION_TYPE_UNKNOWN); |
0e43bcbf | 173 | |
c0e2990d | 174 | return lttng_action_type_string(action_type); |
f2b3ef9f JG |
175 | } |
176 | ||
177 | /* Check if this trigger allowed to interect with a given session. */ | |
178 | static bool is_trigger_allowed_for_session(const struct lttng_trigger *trigger, | |
179 | struct ltt_session *session) | |
180 | { | |
181 | bool is_allowed = false; | |
182 | const struct lttng_credentials session_creds = { | |
ff588497 JR |
183 | .uid = LTTNG_OPTIONAL_INIT_VALUE(session->uid), |
184 | .gid = LTTNG_OPTIONAL_INIT_VALUE(session->gid), | |
f2b3ef9f JG |
185 | }; |
186 | /* Can never be NULL. */ | |
187 | const struct lttng_credentials *trigger_creds = | |
188 | lttng_trigger_get_credentials(trigger); | |
189 | ||
ff588497 JR |
190 | is_allowed = (lttng_credentials_is_equal_uid(trigger_creds, &session_creds)) || |
191 | (lttng_credentials_get_uid(trigger_creds) == 0); | |
f2b3ef9f | 192 | if (!is_allowed) { |
ff588497 | 193 | WARN("Trigger is not allowed to interact with session `%s`: session uid = %ld, session gid = %ld, trigger uid = %ld", |
f2b3ef9f JG |
194 | session->name, |
195 | (long int) session->uid, | |
196 | (long int) session->gid, | |
ff588497 | 197 | (long int) lttng_credentials_get_uid(trigger_creds)); |
f2b3ef9f JG |
198 | } |
199 | ||
200 | return is_allowed; | |
201 | } | |
202 | ||
34f87583 JR |
203 | static const char *get_trigger_name(const struct lttng_trigger *trigger) |
204 | { | |
205 | const char *trigger_name; | |
206 | enum lttng_trigger_status trigger_status; | |
207 | ||
208 | trigger_status = lttng_trigger_get_name(trigger, &trigger_name); | |
0efb2ad7 JG |
209 | switch (trigger_status) { |
210 | case LTTNG_TRIGGER_STATUS_OK: | |
211 | break; | |
212 | case LTTNG_TRIGGER_STATUS_UNSET: | |
213 | trigger_name = "(anonymous)"; | |
214 | break; | |
215 | default: | |
216 | trigger_name = "(failed to get name)"; | |
217 | break; | |
218 | } | |
34f87583 JR |
219 | |
220 | return trigger_name; | |
221 | } | |
222 | ||
f2b3ef9f JG |
223 | static int client_handle_transmission_status( |
224 | struct notification_client *client, | |
225 | enum client_transmission_status status, | |
226 | void *user_data) | |
227 | { | |
228 | int ret = 0; | |
7966af57 | 229 | struct action_executor *executor = (action_executor *) user_data; |
f2b3ef9f JG |
230 | bool update_communication = true; |
231 | ||
f2b3ef9f JG |
232 | switch (status) { |
233 | case CLIENT_TRANSMISSION_STATUS_COMPLETE: | |
234 | DBG("Successfully sent full notification to client, client_id = %" PRIu64, | |
235 | client->id); | |
236 | update_communication = false; | |
237 | break; | |
238 | case CLIENT_TRANSMISSION_STATUS_QUEUED: | |
239 | DBG("Queued notification in client outgoing buffer, client_id = %" PRIu64, | |
240 | client->id); | |
241 | break; | |
242 | case CLIENT_TRANSMISSION_STATUS_FAIL: | |
243 | DBG("Communication error occurred while sending notification to client, client_id = %" PRIu64, | |
244 | client->id); | |
f2b3ef9f JG |
245 | break; |
246 | default: | |
247 | ERR("Fatal error encoutered while sending notification to client, client_id = %" PRIu64, | |
248 | client->id); | |
f2b3ef9f JG |
249 | ret = -1; |
250 | goto end; | |
251 | } | |
252 | ||
253 | if (!update_communication) { | |
254 | goto end; | |
255 | } | |
256 | ||
6c24d3fd | 257 | /* Safe to read client's id without locking as it is immutable. */ |
f2b3ef9f JG |
258 | ret = notification_thread_client_communication_update( |
259 | executor->notification_thread_handle, client->id, | |
260 | status); | |
261 | end: | |
262 | return ret; | |
263 | } | |
264 | ||
265 | static int action_executor_notify_handler(struct action_executor *executor, | |
266 | const struct action_work_item *work_item, | |
f46376a1 | 267 | struct action_work_subitem *item __attribute__((unused))) |
f2b3ef9f JG |
268 | { |
269 | return notification_client_list_send_evaluation(work_item->client_list, | |
52d55cf9 | 270 | work_item->trigger, |
f2b3ef9f | 271 | work_item->evaluation, |
c203f058 JR |
272 | work_item->object_creds.is_set ? |
273 | &(work_item->object_creds.value) : | |
274 | NULL, | |
64eafdf6 | 275 | client_handle_transmission_status, executor); |
f2b3ef9f JG |
276 | } |
277 | ||
2d57482c | 278 | static int action_executor_start_session_handler( |
f46376a1 | 279 | struct action_executor *executor __attribute__((unused)), |
f2b3ef9f | 280 | const struct action_work_item *work_item, |
72365501 | 281 | struct action_work_subitem *item) |
f2b3ef9f JG |
282 | { |
283 | int ret = 0; | |
284 | const char *session_name; | |
285 | enum lttng_action_status action_status; | |
286 | struct ltt_session *session; | |
287 | enum lttng_error_code cmd_ret; | |
72365501 | 288 | struct lttng_action *action = item->action; |
f2b3ef9f JG |
289 | |
290 | action_status = lttng_action_start_session_get_session_name( | |
291 | action, &session_name); | |
292 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
293 | ERR("Failed to get session name from `%s` action", | |
294 | get_action_name(action)); | |
295 | ret = -1; | |
296 | goto end; | |
297 | } | |
298 | ||
72365501 JR |
299 | /* |
300 | * Validate if at the moment of the action was queued the session | |
301 | * existed. If not skip the action altogether. | |
302 | */ | |
303 | if (!item->context.session_id.is_set) { | |
4ec6f5b6 | 304 | DBG("Session `%s` was not present at the moment the work item was enqueued for `%s` action of trigger `%s`", |
72365501 JR |
305 | session_name, get_action_name(action), |
306 | get_trigger_name(work_item->trigger)); | |
307 | lttng_action_increase_execution_failure_count(action); | |
72365501 JR |
308 | goto end; |
309 | } | |
310 | ||
f2b3ef9f | 311 | session_lock_list(); |
c9753f72 | 312 | rcu_read_lock(); |
4a467a84 | 313 | session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id)); |
f2b3ef9f | 314 | if (!session) { |
34f87583 | 315 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`", |
f2b3ef9f | 316 | session_name, get_action_name(action), |
34f87583 | 317 | get_trigger_name(work_item->trigger)); |
4a467a84 | 318 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
319 | goto error_unlock_list; |
320 | } | |
321 | ||
4a467a84 JR |
322 | session_lock(session); |
323 | if (session->destroyed) { | |
4ec6f5b6 | 324 | DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`", |
4a467a84 | 325 | session->name, session->id, |
72365501 JR |
326 | get_action_name(action), |
327 | get_trigger_name(work_item->trigger)); | |
4a467a84 | 328 | goto error_unlock_session; |
72365501 JR |
329 | } |
330 | ||
f2b3ef9f | 331 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { |
635e0160 | 332 | goto error_unlock_session; |
f2b3ef9f JG |
333 | } |
334 | ||
7966af57 | 335 | cmd_ret = (lttng_error_code) cmd_start_trace(session); |
f2b3ef9f JG |
336 | switch (cmd_ret) { |
337 | case LTTNG_OK: | |
34f87583 JR |
338 | DBG("Successfully started session `%s` on behalf of trigger `%s`", |
339 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
340 | break; |
341 | case LTTNG_ERR_TRACE_ALREADY_STARTED: | |
34f87583 JR |
342 | DBG("Attempted to start session `%s` on behalf of trigger `%s` but it was already started", |
343 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
344 | break; |
345 | default: | |
34f87583 JR |
346 | WARN("Failed to start session `%s` on behalf of trigger `%s`: %s", |
347 | session_name, get_trigger_name(work_item->trigger), | |
f2b3ef9f | 348 | lttng_strerror(-cmd_ret)); |
2d57482c | 349 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
350 | break; |
351 | } | |
352 | ||
635e0160 | 353 | error_unlock_session: |
f2b3ef9f JG |
354 | session_unlock(session); |
355 | session_put(session); | |
356 | error_unlock_list: | |
c9753f72 | 357 | rcu_read_unlock(); |
f2b3ef9f JG |
358 | session_unlock_list(); |
359 | end: | |
360 | return ret; | |
361 | } | |
362 | ||
2d57482c | 363 | static int action_executor_stop_session_handler( |
f46376a1 | 364 | struct action_executor *executor __attribute__((unused)), |
f2b3ef9f | 365 | const struct action_work_item *work_item, |
72365501 | 366 | struct action_work_subitem *item) |
f2b3ef9f JG |
367 | { |
368 | int ret = 0; | |
369 | const char *session_name; | |
370 | enum lttng_action_status action_status; | |
371 | struct ltt_session *session; | |
372 | enum lttng_error_code cmd_ret; | |
72365501 | 373 | struct lttng_action *action = item->action; |
f2b3ef9f JG |
374 | |
375 | action_status = lttng_action_stop_session_get_session_name( | |
376 | action, &session_name); | |
377 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
378 | ERR("Failed to get session name from `%s` action", | |
379 | get_action_name(action)); | |
380 | ret = -1; | |
381 | goto end; | |
382 | } | |
383 | ||
72365501 JR |
384 | /* |
385 | * Validate if, at the moment the action was queued, the target session | |
386 | * existed. If not, skip the action altogether. | |
387 | */ | |
388 | if (!item->context.session_id.is_set) { | |
4ec6f5b6 | 389 | DBG("Session `%s` was not present at the moment the work item was enqueued for `%s` action of trigger `%s`", |
72365501 JR |
390 | session_name, get_action_name(action), |
391 | get_trigger_name(work_item->trigger)); | |
392 | lttng_action_increase_execution_failure_count(action); | |
72365501 JR |
393 | goto end; |
394 | } | |
395 | ||
f2b3ef9f | 396 | session_lock_list(); |
c9753f72 | 397 | rcu_read_lock(); |
4a467a84 | 398 | session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id)); |
f2b3ef9f | 399 | if (!session) { |
34f87583 | 400 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`", |
f2b3ef9f | 401 | session_name, get_action_name(action), |
34f87583 | 402 | get_trigger_name(work_item->trigger)); |
2d57482c | 403 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
404 | goto error_unlock_list; |
405 | } | |
406 | ||
4a467a84 JR |
407 | session_lock(session); |
408 | if (session->destroyed) { | |
4ec6f5b6 | 409 | DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`", |
4a467a84 | 410 | session->name, session->id, |
72365501 JR |
411 | get_action_name(action), |
412 | get_trigger_name(work_item->trigger)); | |
4a467a84 | 413 | goto error_unlock_session; |
72365501 JR |
414 | } |
415 | ||
f2b3ef9f | 416 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { |
635e0160 | 417 | goto error_unlock_session; |
f2b3ef9f JG |
418 | } |
419 | ||
7966af57 | 420 | cmd_ret = (lttng_error_code) cmd_stop_trace(session); |
f2b3ef9f JG |
421 | switch (cmd_ret) { |
422 | case LTTNG_OK: | |
34f87583 JR |
423 | DBG("Successfully stopped session `%s` on behalf of trigger `%s`", |
424 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
425 | break; |
426 | case LTTNG_ERR_TRACE_ALREADY_STOPPED: | |
34f87583 JR |
427 | DBG("Attempted to stop session `%s` on behalf of trigger `%s` but it was already stopped", |
428 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
429 | break; |
430 | default: | |
34f87583 JR |
431 | WARN("Failed to stop session `%s` on behalf of trigger `%s`: %s", |
432 | session_name, get_trigger_name(work_item->trigger), | |
f2b3ef9f | 433 | lttng_strerror(-cmd_ret)); |
2d57482c | 434 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
435 | break; |
436 | } | |
437 | ||
635e0160 | 438 | error_unlock_session: |
f2b3ef9f JG |
439 | session_unlock(session); |
440 | session_put(session); | |
441 | error_unlock_list: | |
c9753f72 | 442 | rcu_read_unlock(); |
f2b3ef9f JG |
443 | session_unlock_list(); |
444 | end: | |
445 | return ret; | |
446 | } | |
447 | ||
2d57482c | 448 | static int action_executor_rotate_session_handler( |
f46376a1 | 449 | struct action_executor *executor __attribute__((unused)), |
f2b3ef9f | 450 | const struct action_work_item *work_item, |
72365501 | 451 | struct action_work_subitem *item) |
f2b3ef9f JG |
452 | { |
453 | int ret = 0; | |
454 | const char *session_name; | |
455 | enum lttng_action_status action_status; | |
456 | struct ltt_session *session; | |
457 | enum lttng_error_code cmd_ret; | |
72365501 | 458 | struct lttng_action *action = item->action; |
f2b3ef9f JG |
459 | |
460 | action_status = lttng_action_rotate_session_get_session_name( | |
461 | action, &session_name); | |
462 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
463 | ERR("Failed to get session name from `%s` action", | |
464 | get_action_name(action)); | |
465 | ret = -1; | |
466 | goto end; | |
467 | } | |
468 | ||
72365501 JR |
469 | /* |
470 | * Validate if, at the moment the action was queued, the target session | |
471 | * existed. If not, skip the action altogether. | |
472 | */ | |
473 | if (!item->context.session_id.is_set) { | |
4ec6f5b6 | 474 | DBG("Session `%s` was not present at the moment the work item was enqueued for `%s` action of trigger `%s`", |
72365501 JR |
475 | session_name, get_action_name(action), |
476 | get_trigger_name(work_item->trigger)); | |
477 | lttng_action_increase_execution_failure_count(action); | |
72365501 JR |
478 | goto end; |
479 | } | |
480 | ||
f2b3ef9f | 481 | session_lock_list(); |
c9753f72 | 482 | rcu_read_lock(); |
4a467a84 | 483 | session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id)); |
f2b3ef9f | 484 | if (!session) { |
34f87583 | 485 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`", |
f2b3ef9f | 486 | session_name, get_action_name(action), |
34f87583 | 487 | get_trigger_name(work_item->trigger)); |
2d57482c | 488 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
489 | goto error_unlock_list; |
490 | } | |
491 | ||
4a467a84 JR |
492 | session_lock(session); |
493 | if (session->destroyed) { | |
4ec6f5b6 | 494 | DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`", |
4a467a84 | 495 | session->name, session->id, |
72365501 JR |
496 | get_action_name(action), |
497 | get_trigger_name(work_item->trigger)); | |
4a467a84 | 498 | goto error_unlock_session; |
72365501 JR |
499 | } |
500 | ||
f2b3ef9f | 501 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { |
635e0160 | 502 | goto error_unlock_session; |
f2b3ef9f JG |
503 | } |
504 | ||
7966af57 | 505 | cmd_ret = (lttng_error_code) cmd_rotate_session(session, NULL, false, |
f2b3ef9f JG |
506 | LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED); |
507 | switch (cmd_ret) { | |
508 | case LTTNG_OK: | |
34f87583 JR |
509 | DBG("Successfully started rotation of session `%s` on behalf of trigger `%s`", |
510 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
511 | break; |
512 | case LTTNG_ERR_ROTATION_PENDING: | |
34f87583 JR |
513 | DBG("Attempted to start a rotation of session `%s` on behalf of trigger `%s` but a rotation is already ongoing", |
514 | session_name, get_trigger_name(work_item->trigger)); | |
2d57482c | 515 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
516 | break; |
517 | case LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP: | |
518 | case LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR: | |
34f87583 JR |
519 | DBG("Attempted to start a rotation of session `%s` on behalf of trigger `%s` but a rotation has already been completed since the last stop or clear", |
520 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
521 | break; |
522 | default: | |
34f87583 JR |
523 | WARN("Failed to start a rotation of session `%s` on behalf of trigger `%s`: %s", |
524 | session_name, get_trigger_name(work_item->trigger), | |
f2b3ef9f | 525 | lttng_strerror(-cmd_ret)); |
2d57482c | 526 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
527 | break; |
528 | } | |
529 | ||
635e0160 | 530 | error_unlock_session: |
f2b3ef9f JG |
531 | session_unlock(session); |
532 | session_put(session); | |
533 | error_unlock_list: | |
c9753f72 | 534 | rcu_read_unlock(); |
f2b3ef9f JG |
535 | session_unlock_list(); |
536 | end: | |
537 | return ret; | |
538 | } | |
539 | ||
2d57482c | 540 | static int action_executor_snapshot_session_handler( |
f46376a1 | 541 | struct action_executor *executor __attribute__((unused)), |
f2b3ef9f | 542 | const struct action_work_item *work_item, |
72365501 | 543 | struct action_work_subitem *item) |
f2b3ef9f JG |
544 | { |
545 | int ret = 0; | |
546 | const char *session_name; | |
547 | enum lttng_action_status action_status; | |
548 | struct ltt_session *session; | |
7966af57 | 549 | lttng_snapshot_output default_snapshot_output; |
f2b3ef9f JG |
550 | const struct lttng_snapshot_output *snapshot_output = |
551 | &default_snapshot_output; | |
552 | enum lttng_error_code cmd_ret; | |
72365501 JR |
553 | struct lttng_action *action = item->action; |
554 | ||
7966af57 SM |
555 | default_snapshot_output.max_size = UINT64_MAX; |
556 | ||
72365501 JR |
557 | /* |
558 | * Validate if, at the moment the action was queued, the target session | |
559 | * existed. If not, skip the action altogether. | |
560 | */ | |
561 | if (!item->context.session_id.is_set) { | |
4ec6f5b6 | 562 | DBG("Session was not present at the moment the work item was enqueued for `%s` action of trigger `%s`", |
42ef691e | 563 | get_action_name(action), |
72365501 JR |
564 | get_trigger_name(work_item->trigger)); |
565 | lttng_action_increase_execution_failure_count(action); | |
72365501 JR |
566 | goto end; |
567 | } | |
f2b3ef9f JG |
568 | |
569 | action_status = lttng_action_snapshot_session_get_session_name( | |
570 | action, &session_name); | |
571 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
572 | ERR("Failed to get session name from `%s` action", | |
573 | get_action_name(action)); | |
574 | ret = -1; | |
575 | goto end; | |
576 | } | |
577 | ||
578 | action_status = lttng_action_snapshot_session_get_output( | |
579 | action, &snapshot_output); | |
580 | if (action_status != LTTNG_ACTION_STATUS_OK && | |
581 | action_status != LTTNG_ACTION_STATUS_UNSET) { | |
582 | ERR("Failed to get output from `%s` action", | |
583 | get_action_name(action)); | |
584 | ret = -1; | |
585 | goto end; | |
586 | } | |
587 | ||
588 | session_lock_list(); | |
c9753f72 | 589 | rcu_read_lock(); |
4a467a84 | 590 | session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id)); |
f2b3ef9f | 591 | if (!session) { |
ca46af4e | 592 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`", |
f2b3ef9f | 593 | session_name, get_action_name(action), |
ca46af4e | 594 | get_trigger_name(work_item->trigger)); |
2d57482c | 595 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
596 | goto error_unlock_list; |
597 | } | |
598 | ||
4a467a84 JR |
599 | session_lock(session); |
600 | if (session->destroyed) { | |
4ec6f5b6 | 601 | DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`", |
4a467a84 | 602 | session->name, session->id, |
72365501 JR |
603 | get_action_name(action), |
604 | get_trigger_name(work_item->trigger)); | |
4a467a84 | 605 | goto error_unlock_session; |
72365501 | 606 | } |
f2b3ef9f | 607 | |
f2b3ef9f | 608 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { |
635e0160 | 609 | goto error_unlock_session; |
f2b3ef9f JG |
610 | } |
611 | ||
7966af57 | 612 | cmd_ret = (lttng_error_code) cmd_snapshot_record(session, snapshot_output, 0); |
f2b3ef9f JG |
613 | switch (cmd_ret) { |
614 | case LTTNG_OK: | |
34f87583 JR |
615 | DBG("Successfully recorded snapshot of session `%s` on behalf of trigger `%s`", |
616 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
617 | break; |
618 | default: | |
34f87583 JR |
619 | WARN("Failed to record snapshot of session `%s` on behalf of trigger `%s`: %s", |
620 | session_name, get_trigger_name(work_item->trigger), | |
f2b3ef9f | 621 | lttng_strerror(-cmd_ret)); |
2d57482c | 622 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
623 | break; |
624 | } | |
625 | ||
635e0160 | 626 | error_unlock_session: |
f2b3ef9f JG |
627 | session_unlock(session); |
628 | session_put(session); | |
629 | error_unlock_list: | |
c9753f72 | 630 | rcu_read_unlock(); |
f2b3ef9f JG |
631 | session_unlock_list(); |
632 | end: | |
633 | return ret; | |
634 | } | |
635 | ||
f46376a1 MJ |
636 | static int action_executor_list_handler( |
637 | struct action_executor *executor __attribute__((unused)), | |
638 | const struct action_work_item *work_item __attribute__((unused)), | |
639 | struct action_work_subitem *item __attribute__((unused))) | |
f2b3ef9f | 640 | { |
7c2fae7c | 641 | ERR("Execution of a list action by the action executor should never occur"); |
72365501 | 642 | abort(); |
f2b3ef9f JG |
643 | } |
644 | ||
645 | static int action_executor_generic_handler(struct action_executor *executor, | |
646 | const struct action_work_item *work_item, | |
72365501 | 647 | struct action_work_subitem *item) |
f2b3ef9f | 648 | { |
2d57482c | 649 | int ret; |
72365501 | 650 | struct lttng_action *action = item->action; |
0e43bcbf JG |
651 | const enum lttng_action_type action_type = lttng_action_get_type(action); |
652 | ||
a0377dfe | 653 | LTTNG_ASSERT(action_type != LTTNG_ACTION_TYPE_UNKNOWN); |
0e43bcbf | 654 | |
2d57482c JR |
655 | lttng_action_increase_execution_request_count(action); |
656 | if (!lttng_action_should_execute(action)) { | |
657 | DBG("Policy prevented execution of action `%s` of trigger `%s` action work item %" PRIu64, | |
658 | get_action_name(action), | |
659 | get_trigger_name(work_item->trigger), | |
660 | work_item->id); | |
661 | ret = 0; | |
662 | goto end; | |
663 | } | |
664 | ||
665 | lttng_action_increase_execution_count(action); | |
2516f2d8 | 666 | DBG("Executing action `%s` of trigger `%s` action work item %" PRIu64, |
f2b3ef9f | 667 | get_action_name(action), |
34f87583 | 668 | get_trigger_name(work_item->trigger), |
f2b3ef9f | 669 | work_item->id); |
72365501 | 670 | ret = action_executors[action_type](executor, work_item, item); |
2d57482c JR |
671 | end: |
672 | return ret; | |
f2b3ef9f JG |
673 | } |
674 | ||
675 | static int action_work_item_execute(struct action_executor *executor, | |
676 | struct action_work_item *work_item) | |
677 | { | |
678 | int ret; | |
72365501 | 679 | size_t count, i; |
f2b3ef9f | 680 | |
34f87583 JR |
681 | DBG("Starting execution of action work item %" PRIu64 " of trigger `%s`", |
682 | work_item->id, get_trigger_name(work_item->trigger)); | |
72365501 | 683 | |
be65f802 | 684 | count = lttng_dynamic_array_get_count(&work_item->subitems); |
72365501 JR |
685 | for (i = 0; i < count; i++) { |
686 | struct action_work_subitem *item; | |
687 | ||
7966af57 | 688 | item = (action_work_subitem *) lttng_dynamic_array_get_element(&work_item->subitems, i); |
72365501 JR |
689 | ret = action_executor_generic_handler( |
690 | executor, work_item, item); | |
691 | if (ret) { | |
692 | goto end; | |
693 | } | |
694 | } | |
695 | end: | |
34f87583 JR |
696 | DBG("Completed execution of action work item %" PRIu64 " of trigger `%s`", |
697 | work_item->id, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
698 | return ret; |
699 | } | |
700 | ||
701 | static void action_work_item_destroy(struct action_work_item *work_item) | |
702 | { | |
703 | lttng_trigger_put(work_item->trigger); | |
704 | lttng_evaluation_destroy(work_item->evaluation); | |
705 | notification_client_list_put(work_item->client_list); | |
be65f802 | 706 | lttng_dynamic_array_reset(&work_item->subitems); |
f2b3ef9f JG |
707 | free(work_item); |
708 | } | |
709 | ||
710 | static void *action_executor_thread(void *_data) | |
711 | { | |
7966af57 | 712 | struct action_executor *executor = (action_executor *) _data; |
f2b3ef9f | 713 | |
a0377dfe | 714 | LTTNG_ASSERT(executor); |
f2b3ef9f | 715 | |
412d7227 SM |
716 | health_register(the_health_sessiond, |
717 | HEALTH_SESSIOND_TYPE_ACTION_EXECUTOR); | |
f2b3ef9f JG |
718 | |
719 | rcu_register_thread(); | |
720 | rcu_thread_online(); | |
721 | ||
722 | DBG("Entering work execution loop"); | |
723 | pthread_mutex_lock(&executor->work.lock); | |
724 | while (!executor->should_quit) { | |
da247508 | 725 | int ret = 0; |
f2b3ef9f JG |
726 | struct action_work_item *work_item; |
727 | ||
728 | health_code_update(); | |
729 | if (executor->work.pending_count == 0) { | |
730 | health_poll_entry(); | |
731 | DBG("No work items enqueued, entering wait"); | |
732 | pthread_cond_wait(&executor->work.cond, | |
733 | &executor->work.lock); | |
734 | DBG("Woke-up from wait"); | |
735 | health_poll_exit(); | |
736 | continue; | |
737 | } | |
738 | ||
0db0f8e0 | 739 | /* Pop item from front of the list with work lock held. */ |
f2b3ef9f JG |
740 | work_item = cds_list_first_entry(&executor->work.list, |
741 | struct action_work_item, list_node); | |
742 | cds_list_del(&work_item->list_node); | |
743 | executor->work.pending_count--; | |
744 | ||
745 | /* | |
746 | * Work can be performed without holding the work lock, | |
747 | * allowing new items to be queued. | |
748 | */ | |
749 | pthread_mutex_unlock(&executor->work.lock); | |
d2a28b27 JR |
750 | |
751 | /* Execute item only if a trigger is registered. */ | |
752 | lttng_trigger_lock(work_item->trigger); | |
753 | if (!lttng_trigger_is_registered(work_item->trigger)) { | |
754 | const char *trigger_name = NULL; | |
755 | uid_t trigger_owner_uid; | |
756 | enum lttng_trigger_status trigger_status; | |
757 | ||
0efb2ad7 | 758 | trigger_name = get_trigger_name(work_item->trigger); |
d2a28b27 JR |
759 | |
760 | trigger_status = lttng_trigger_get_owner_uid( | |
761 | work_item->trigger, &trigger_owner_uid); | |
a0377dfe | 762 | LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK); |
d2a28b27 | 763 | |
4ec6f5b6 | 764 | DBG("Work item skipped since the associated trigger is no longer registered: work item id = %" PRIu64 ", trigger name = `%s`, trigger owner uid = %d", |
d2a28b27 JR |
765 | work_item->id, trigger_name, |
766 | (int) trigger_owner_uid); | |
767 | ret = 0; | |
768 | goto skip_execute; | |
769 | } | |
770 | ||
f2b3ef9f | 771 | ret = action_work_item_execute(executor, work_item); |
d2a28b27 JR |
772 | |
773 | skip_execute: | |
774 | lttng_trigger_unlock(work_item->trigger); | |
f2b3ef9f JG |
775 | action_work_item_destroy(work_item); |
776 | if (ret) { | |
777 | /* Fatal error. */ | |
778 | break; | |
779 | } | |
780 | ||
781 | health_code_update(); | |
782 | pthread_mutex_lock(&executor->work.lock); | |
783 | } | |
784 | ||
f5f5c54d JG |
785 | if (executor->should_quit) { |
786 | pthread_mutex_unlock(&executor->work.lock); | |
787 | } | |
f2b3ef9f JG |
788 | DBG("Left work execution loop"); |
789 | ||
790 | health_code_update(); | |
791 | ||
792 | rcu_thread_offline(); | |
793 | rcu_unregister_thread(); | |
412d7227 | 794 | health_unregister(the_health_sessiond); |
f2b3ef9f JG |
795 | |
796 | return NULL; | |
797 | } | |
798 | ||
799 | static bool shutdown_action_executor_thread(void *_data) | |
800 | { | |
7966af57 | 801 | struct action_executor *executor = (action_executor *) _data; |
f2b3ef9f | 802 | |
8db3acaf | 803 | pthread_mutex_lock(&executor->work.lock); |
f2b3ef9f JG |
804 | executor->should_quit = true; |
805 | pthread_cond_signal(&executor->work.cond); | |
8db3acaf | 806 | pthread_mutex_unlock(&executor->work.lock); |
f2b3ef9f JG |
807 | return true; |
808 | } | |
809 | ||
810 | static void clean_up_action_executor_thread(void *_data) | |
811 | { | |
7966af57 | 812 | struct action_executor *executor = (action_executor *) _data; |
f2b3ef9f | 813 | |
a0377dfe | 814 | LTTNG_ASSERT(cds_list_empty(&executor->work.list)); |
f2b3ef9f JG |
815 | |
816 | pthread_mutex_destroy(&executor->work.lock); | |
817 | pthread_cond_destroy(&executor->work.cond); | |
818 | free(executor); | |
819 | } | |
820 | ||
821 | struct action_executor *action_executor_create( | |
822 | struct notification_thread_handle *handle) | |
823 | { | |
7966af57 | 824 | struct action_executor *executor = (action_executor *) zmalloc(sizeof(*executor)); |
f2b3ef9f JG |
825 | |
826 | if (!executor) { | |
827 | goto end; | |
828 | } | |
829 | ||
830 | CDS_INIT_LIST_HEAD(&executor->work.list); | |
831 | pthread_cond_init(&executor->work.cond, NULL); | |
832 | pthread_mutex_init(&executor->work.lock, NULL); | |
833 | executor->notification_thread_handle = handle; | |
834 | ||
835 | executor->thread = lttng_thread_create(THREAD_NAME, | |
836 | action_executor_thread, shutdown_action_executor_thread, | |
837 | clean_up_action_executor_thread, executor); | |
838 | end: | |
839 | return executor; | |
840 | } | |
841 | ||
842 | void action_executor_destroy(struct action_executor *executor) | |
843 | { | |
844 | struct action_work_item *work_item, *tmp; | |
845 | ||
846 | /* TODO Wait for work list to drain? */ | |
847 | lttng_thread_shutdown(executor->thread); | |
848 | pthread_mutex_lock(&executor->work.lock); | |
849 | if (executor->work.pending_count != 0) { | |
850 | WARN("%" PRIu64 | |
851 | " trigger action%s still queued for execution and will be discarded", | |
852 | executor->work.pending_count, | |
853 | executor->work.pending_count == 1 ? " is" : | |
854 | "s are"); | |
855 | } | |
856 | ||
857 | cds_list_for_each_entry_safe ( | |
858 | work_item, tmp, &executor->work.list, list_node) { | |
859 | WARN("Discarding action work item %" PRIu64 | |
34f87583 JR |
860 | " associated to trigger `%s`", |
861 | work_item->id, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
862 | cds_list_del(&work_item->list_node); |
863 | action_work_item_destroy(work_item); | |
864 | } | |
865 | pthread_mutex_unlock(&executor->work.lock); | |
866 | lttng_thread_put(executor->thread); | |
867 | } | |
868 | ||
869 | /* RCU read-lock must be held by the caller. */ | |
72365501 | 870 | enum action_executor_status action_executor_enqueue_trigger( |
f2b3ef9f JG |
871 | struct action_executor *executor, |
872 | struct lttng_trigger *trigger, | |
873 | struct lttng_evaluation *evaluation, | |
874 | const struct lttng_credentials *object_creds, | |
875 | struct notification_client_list *client_list) | |
876 | { | |
72365501 | 877 | int ret; |
f2b3ef9f JG |
878 | enum action_executor_status executor_status = ACTION_EXECUTOR_STATUS_OK; |
879 | const uint64_t work_item_id = executor->next_work_item_id++; | |
880 | struct action_work_item *work_item; | |
881 | bool signal = false; | |
72365501 | 882 | |
a0377dfe | 883 | LTTNG_ASSERT(trigger); |
48b7cdc2 | 884 | ASSERT_RCU_READ_LOCKED(); |
72365501 | 885 | |
f2b3ef9f JG |
886 | pthread_mutex_lock(&executor->work.lock); |
887 | /* Check for queue overflow. */ | |
888 | if (executor->work.pending_count >= MAX_QUEUED_WORK_COUNT) { | |
889 | /* Most likely spammy, remove if it is the case. */ | |
72365501 JR |
890 | DBG("Refusing to enqueue action for trigger (overflow): trigger name = `%s`, work item id = %" PRIu64, |
891 | get_trigger_name(trigger), work_item_id); | |
f2b3ef9f JG |
892 | executor_status = ACTION_EXECUTOR_STATUS_OVERFLOW; |
893 | goto error_unlock; | |
894 | } | |
895 | ||
7966af57 | 896 | work_item = (action_work_item *) zmalloc(sizeof(*work_item)); |
f2b3ef9f | 897 | if (!work_item) { |
4ec6f5b6 | 898 | PERROR("Failed to allocate action executor work item: trigger name = `%s`", |
34f87583 | 899 | get_trigger_name(trigger)); |
f2b3ef9f JG |
900 | executor_status = ACTION_EXECUTOR_STATUS_ERROR; |
901 | goto error_unlock; | |
902 | } | |
903 | ||
904 | lttng_trigger_get(trigger); | |
905 | if (client_list) { | |
906 | const bool reference_acquired = | |
907 | notification_client_list_get(client_list); | |
908 | ||
a0377dfe | 909 | LTTNG_ASSERT(reference_acquired); |
f2b3ef9f JG |
910 | } |
911 | ||
7966af57 SM |
912 | work_item->id = work_item_id; |
913 | work_item->trigger = trigger; | |
f2b3ef9f | 914 | |
7966af57 SM |
915 | /* Ownership transferred to the work item. */ |
916 | work_item->evaluation = evaluation; | |
f2b3ef9f | 917 | evaluation = NULL; |
be65f802 | 918 | |
7966af57 SM |
919 | work_item->client_list = client_list; |
920 | work_item->object_creds.is_set = !!object_creds; | |
921 | if (object_creds) { | |
922 | work_item->object_creds.value = *object_creds; | |
923 | } | |
924 | ||
925 | CDS_INIT_LIST_HEAD(&work_item->list_node); | |
926 | ||
be65f802 JG |
927 | /* Build the array of action work subitems for the passed trigger. */ |
928 | lttng_dynamic_array_init(&work_item->subitems, | |
929 | sizeof(struct action_work_subitem), | |
930 | action_work_subitem_destructor); | |
931 | ||
932 | ret = populate_subitem_array_from_trigger( | |
933 | trigger, &work_item->subitems); | |
934 | if (ret) { | |
935 | ERR("Failed to populate work item sub items on behalf of trigger: trigger name = `%s`", | |
936 | get_trigger_name(trigger)); | |
937 | executor_status = ACTION_EXECUTOR_STATUS_ERROR; | |
938 | goto error_unlock; | |
939 | } | |
940 | ||
f2b3ef9f JG |
941 | cds_list_add_tail(&work_item->list_node, &executor->work.list); |
942 | executor->work.pending_count++; | |
72365501 | 943 | DBG("Enqueued action for trigger: trigger name = `%s`, work item id = %" PRIu64, |
34f87583 | 944 | get_trigger_name(trigger), work_item_id); |
f2b3ef9f JG |
945 | signal = true; |
946 | ||
947 | error_unlock: | |
f2b3ef9f JG |
948 | if (signal) { |
949 | pthread_cond_signal(&executor->work.cond); | |
950 | } | |
951 | ||
be65f802 | 952 | pthread_mutex_unlock(&executor->work.lock); |
f2b3ef9f JG |
953 | lttng_evaluation_destroy(evaluation); |
954 | return executor_status; | |
955 | } | |
72365501 JR |
956 | |
957 | static int add_action_to_subitem_array(struct lttng_action *action, | |
958 | struct lttng_dynamic_array *subitems) | |
959 | { | |
da247508 | 960 | int ret = 0; |
72365501 JR |
961 | enum lttng_action_type type = lttng_action_get_type(action); |
962 | const char *session_name = NULL; | |
963 | enum lttng_action_status status; | |
964 | struct action_work_subitem subitem = { | |
965 | .action = NULL, | |
966 | .context = { | |
967 | .session_id = LTTNG_OPTIONAL_INIT_UNSET, | |
968 | }, | |
969 | }; | |
970 | ||
a0377dfe FD |
971 | LTTNG_ASSERT(action); |
972 | LTTNG_ASSERT(subitems); | |
72365501 | 973 | |
7c2fae7c | 974 | if (type == LTTNG_ACTION_TYPE_LIST) { |
72365501 JR |
975 | unsigned int count, i; |
976 | ||
702f26c8 | 977 | status = lttng_action_list_get_count(action, &count); |
a0377dfe | 978 | LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK); |
72365501 JR |
979 | |
980 | for (i = 0; i < count; i++) { | |
981 | struct lttng_action *inner_action = NULL; | |
982 | ||
702f26c8 | 983 | inner_action = lttng_action_list_borrow_mutable_at_index( |
72365501 | 984 | action, i); |
a0377dfe | 985 | LTTNG_ASSERT(inner_action); |
72365501 JR |
986 | ret = add_action_to_subitem_array( |
987 | inner_action, subitems); | |
988 | if (ret) { | |
989 | goto end; | |
990 | } | |
991 | } | |
992 | ||
993 | /* | |
994 | * Go directly to the end since there is no need to add the | |
7c2fae7c | 995 | * list action by itself to the subitems array. |
72365501 JR |
996 | */ |
997 | goto end; | |
998 | } | |
999 | ||
1000 | /* Gather execution context. */ | |
1001 | switch (type) { | |
1002 | case LTTNG_ACTION_TYPE_NOTIFY: | |
1003 | break; | |
1004 | case LTTNG_ACTION_TYPE_START_SESSION: | |
1005 | status = lttng_action_start_session_get_session_name( | |
1006 | action, &session_name); | |
a0377dfe | 1007 | LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK); |
72365501 JR |
1008 | break; |
1009 | case LTTNG_ACTION_TYPE_STOP_SESSION: | |
1010 | status = lttng_action_stop_session_get_session_name( | |
1011 | action, &session_name); | |
a0377dfe | 1012 | LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK); |
72365501 JR |
1013 | break; |
1014 | case LTTNG_ACTION_TYPE_ROTATE_SESSION: | |
1015 | status = lttng_action_rotate_session_get_session_name( | |
1016 | action, &session_name); | |
a0377dfe | 1017 | LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK); |
72365501 JR |
1018 | break; |
1019 | case LTTNG_ACTION_TYPE_SNAPSHOT_SESSION: | |
1020 | status = lttng_action_snapshot_session_get_session_name( | |
1021 | action, &session_name); | |
a0377dfe | 1022 | LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK); |
72365501 | 1023 | break; |
7c2fae7c | 1024 | case LTTNG_ACTION_TYPE_LIST: |
72365501 JR |
1025 | case LTTNG_ACTION_TYPE_UNKNOWN: |
1026 | /* Fallthrough */ | |
1027 | default: | |
1028 | abort(); | |
1029 | break; | |
1030 | } | |
1031 | ||
1032 | /* | |
1033 | * Fetch the session execution context info as needed. | |
1034 | * Note that we could decide to not add an action for which we know the | |
1035 | * execution will not happen (i.e no session exists for that name). For | |
1036 | * now we leave the decision to skip to the action executor for sake of | |
1037 | * simplicity and consistency. | |
1038 | */ | |
1039 | if (session_name != NULL) { | |
e1bbf989 | 1040 | uint64_t session_id; |
72365501 | 1041 | |
e1bbf989 JR |
1042 | /* |
1043 | * Instantaneous sampling of the session id if present. | |
1044 | * | |
1045 | * This method is preferred over `sessiond_find_by_name` then | |
1046 | * fetching the session'd id since `sessiond_find_by_name` | |
1047 | * requires the session list lock to be taken. | |
1048 | * | |
1049 | * Taking the session list lock can lead to a deadlock | |
1050 | * between the action executor and the notification thread | |
1051 | * (caller of add_action_to_subitem_array). It is okay if the | |
1052 | * session state changes between the enqueuing time and the | |
1053 | * execution time. The execution context is validated at | |
1054 | * execution time. | |
1055 | */ | |
1056 | if (sample_session_id_by_name(session_name, &session_id)) { | |
72365501 | 1057 | LTTNG_OPTIONAL_SET(&subitem.context.session_id, |
e1bbf989 | 1058 | session_id); |
72365501 | 1059 | } |
72365501 JR |
1060 | } |
1061 | ||
1062 | /* Get a reference to the action. */ | |
1063 | lttng_action_get(action); | |
1064 | subitem.action = action; | |
1065 | ||
1066 | ret = lttng_dynamic_array_add_element(subitems, &subitem); | |
1067 | if (ret) { | |
1068 | ERR("Failed to add work subitem to the subitem array"); | |
1069 | lttng_action_put(action); | |
1070 | ret = -1; | |
1071 | goto end; | |
1072 | } | |
1073 | ||
1074 | end: | |
1075 | return ret; | |
1076 | } | |
1077 | ||
1078 | static int populate_subitem_array_from_trigger(struct lttng_trigger *trigger, | |
1079 | struct lttng_dynamic_array *subitems) | |
1080 | { | |
1081 | struct lttng_action *action; | |
1082 | ||
1083 | action = lttng_trigger_get_action(trigger); | |
a0377dfe | 1084 | LTTNG_ASSERT(action); |
72365501 JR |
1085 | |
1086 | return add_action_to_subitem_array(action, subitems); | |
1087 | } |