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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 | ||
c9e313bc SM |
8 | #include "action-executor.hpp" |
9 | #include "cmd.hpp" | |
10 | #include "health-sessiond.hpp" | |
11 | #include "lttng-sessiond.hpp" | |
12 | #include "notification-thread-internal.hpp" | |
13 | #include "session.hpp" | |
14 | #include "thread.hpp" | |
15 | #include <common/dynamic-array.hpp> | |
16 | #include <common/macros.hpp> | |
17 | #include <common/optional.hpp> | |
18 | #include <lttng/action/action-internal.hpp> | |
19 | #include <lttng/action/list-internal.hpp> | |
ad63a966 | 20 | #include <lttng/action/list.h> |
c9e313bc | 21 | #include <lttng/action/notify-internal.hpp> |
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> | |
c9e313bc | 28 | #include <lttng/condition/event-rule-matches-internal.hpp> |
f2b3ef9f | 29 | #include <lttng/lttng-error.h> |
c9e313bc | 30 | #include <lttng/trigger/trigger-internal.hpp> |
f2b3ef9f JG |
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); | |
9016dbfc JG |
236 | /* |
237 | * There is no need to wake the (e)poll thread. If it was waiting for | |
238 | * "out" events on the client's socket, it will see that no payload | |
239 | * in queued and will unsubscribe from that event. | |
240 | * | |
241 | * In the other cases, we have to wake the the (e)poll thread to either | |
242 | * handle the error on the client or to get it to monitor the client "out" | |
243 | * events. | |
244 | */ | |
f2b3ef9f JG |
245 | update_communication = false; |
246 | break; | |
247 | case CLIENT_TRANSMISSION_STATUS_QUEUED: | |
248 | DBG("Queued notification in client outgoing buffer, client_id = %" PRIu64, | |
249 | client->id); | |
250 | break; | |
251 | case CLIENT_TRANSMISSION_STATUS_FAIL: | |
252 | DBG("Communication error occurred while sending notification to client, client_id = %" PRIu64, | |
253 | client->id); | |
f2b3ef9f JG |
254 | break; |
255 | default: | |
256 | ERR("Fatal error encoutered while sending notification to client, client_id = %" PRIu64, | |
257 | client->id); | |
f2b3ef9f JG |
258 | ret = -1; |
259 | goto end; | |
260 | } | |
261 | ||
262 | if (!update_communication) { | |
263 | goto end; | |
264 | } | |
265 | ||
6c24d3fd | 266 | /* Safe to read client's id without locking as it is immutable. */ |
f2b3ef9f JG |
267 | ret = notification_thread_client_communication_update( |
268 | executor->notification_thread_handle, client->id, | |
269 | status); | |
270 | end: | |
271 | return ret; | |
272 | } | |
273 | ||
274 | static int action_executor_notify_handler(struct action_executor *executor, | |
275 | const struct action_work_item *work_item, | |
f46376a1 | 276 | struct action_work_subitem *item __attribute__((unused))) |
f2b3ef9f JG |
277 | { |
278 | return notification_client_list_send_evaluation(work_item->client_list, | |
52d55cf9 | 279 | work_item->trigger, |
f2b3ef9f | 280 | work_item->evaluation, |
c203f058 JR |
281 | work_item->object_creds.is_set ? |
282 | &(work_item->object_creds.value) : | |
283 | NULL, | |
64eafdf6 | 284 | client_handle_transmission_status, executor); |
f2b3ef9f JG |
285 | } |
286 | ||
2d57482c | 287 | static int action_executor_start_session_handler( |
f46376a1 | 288 | struct action_executor *executor __attribute__((unused)), |
f2b3ef9f | 289 | const struct action_work_item *work_item, |
72365501 | 290 | struct action_work_subitem *item) |
f2b3ef9f JG |
291 | { |
292 | int ret = 0; | |
293 | const char *session_name; | |
294 | enum lttng_action_status action_status; | |
295 | struct ltt_session *session; | |
296 | enum lttng_error_code cmd_ret; | |
72365501 | 297 | struct lttng_action *action = item->action; |
f2b3ef9f JG |
298 | |
299 | action_status = lttng_action_start_session_get_session_name( | |
300 | action, &session_name); | |
301 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
302 | ERR("Failed to get session name from `%s` action", | |
303 | get_action_name(action)); | |
304 | ret = -1; | |
305 | goto end; | |
306 | } | |
307 | ||
72365501 JR |
308 | /* |
309 | * Validate if at the moment of the action was queued the session | |
310 | * existed. If not skip the action altogether. | |
311 | */ | |
312 | if (!item->context.session_id.is_set) { | |
4ec6f5b6 | 313 | DBG("Session `%s` was not present at the moment the work item was enqueued for `%s` action of trigger `%s`", |
72365501 JR |
314 | session_name, get_action_name(action), |
315 | get_trigger_name(work_item->trigger)); | |
316 | lttng_action_increase_execution_failure_count(action); | |
72365501 JR |
317 | goto end; |
318 | } | |
319 | ||
f2b3ef9f | 320 | session_lock_list(); |
c9753f72 | 321 | rcu_read_lock(); |
4a467a84 | 322 | session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id)); |
f2b3ef9f | 323 | if (!session) { |
34f87583 | 324 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`", |
f2b3ef9f | 325 | session_name, get_action_name(action), |
34f87583 | 326 | get_trigger_name(work_item->trigger)); |
4a467a84 | 327 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
328 | goto error_unlock_list; |
329 | } | |
330 | ||
4a467a84 JR |
331 | session_lock(session); |
332 | if (session->destroyed) { | |
4ec6f5b6 | 333 | DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`", |
4a467a84 | 334 | session->name, session->id, |
72365501 JR |
335 | get_action_name(action), |
336 | get_trigger_name(work_item->trigger)); | |
4a467a84 | 337 | goto error_unlock_session; |
72365501 JR |
338 | } |
339 | ||
f2b3ef9f | 340 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { |
635e0160 | 341 | goto error_unlock_session; |
f2b3ef9f JG |
342 | } |
343 | ||
7966af57 | 344 | cmd_ret = (lttng_error_code) cmd_start_trace(session); |
f2b3ef9f JG |
345 | switch (cmd_ret) { |
346 | case LTTNG_OK: | |
34f87583 JR |
347 | DBG("Successfully started session `%s` on behalf of trigger `%s`", |
348 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
349 | break; |
350 | case LTTNG_ERR_TRACE_ALREADY_STARTED: | |
34f87583 JR |
351 | DBG("Attempted to start session `%s` on behalf of trigger `%s` but it was already started", |
352 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
353 | break; |
354 | default: | |
34f87583 JR |
355 | WARN("Failed to start session `%s` on behalf of trigger `%s`: %s", |
356 | session_name, get_trigger_name(work_item->trigger), | |
f2b3ef9f | 357 | lttng_strerror(-cmd_ret)); |
2d57482c | 358 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
359 | break; |
360 | } | |
361 | ||
635e0160 | 362 | error_unlock_session: |
f2b3ef9f JG |
363 | session_unlock(session); |
364 | session_put(session); | |
365 | error_unlock_list: | |
c9753f72 | 366 | rcu_read_unlock(); |
f2b3ef9f JG |
367 | session_unlock_list(); |
368 | end: | |
369 | return ret; | |
370 | } | |
371 | ||
2d57482c | 372 | static int action_executor_stop_session_handler( |
f46376a1 | 373 | struct action_executor *executor __attribute__((unused)), |
f2b3ef9f | 374 | const struct action_work_item *work_item, |
72365501 | 375 | struct action_work_subitem *item) |
f2b3ef9f JG |
376 | { |
377 | int ret = 0; | |
378 | const char *session_name; | |
379 | enum lttng_action_status action_status; | |
380 | struct ltt_session *session; | |
381 | enum lttng_error_code cmd_ret; | |
72365501 | 382 | struct lttng_action *action = item->action; |
f2b3ef9f JG |
383 | |
384 | action_status = lttng_action_stop_session_get_session_name( | |
385 | action, &session_name); | |
386 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
387 | ERR("Failed to get session name from `%s` action", | |
388 | get_action_name(action)); | |
389 | ret = -1; | |
390 | goto end; | |
391 | } | |
392 | ||
72365501 JR |
393 | /* |
394 | * Validate if, at the moment the action was queued, the target session | |
395 | * existed. If not, skip the action altogether. | |
396 | */ | |
397 | if (!item->context.session_id.is_set) { | |
4ec6f5b6 | 398 | DBG("Session `%s` was not present at the moment the work item was enqueued for `%s` action of trigger `%s`", |
72365501 JR |
399 | session_name, get_action_name(action), |
400 | get_trigger_name(work_item->trigger)); | |
401 | lttng_action_increase_execution_failure_count(action); | |
72365501 JR |
402 | goto end; |
403 | } | |
404 | ||
f2b3ef9f | 405 | session_lock_list(); |
c9753f72 | 406 | rcu_read_lock(); |
4a467a84 | 407 | session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id)); |
f2b3ef9f | 408 | if (!session) { |
34f87583 | 409 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`", |
f2b3ef9f | 410 | session_name, get_action_name(action), |
34f87583 | 411 | get_trigger_name(work_item->trigger)); |
2d57482c | 412 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
413 | goto error_unlock_list; |
414 | } | |
415 | ||
4a467a84 JR |
416 | session_lock(session); |
417 | if (session->destroyed) { | |
4ec6f5b6 | 418 | DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`", |
4a467a84 | 419 | session->name, session->id, |
72365501 JR |
420 | get_action_name(action), |
421 | get_trigger_name(work_item->trigger)); | |
4a467a84 | 422 | goto error_unlock_session; |
72365501 JR |
423 | } |
424 | ||
f2b3ef9f | 425 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { |
635e0160 | 426 | goto error_unlock_session; |
f2b3ef9f JG |
427 | } |
428 | ||
7966af57 | 429 | cmd_ret = (lttng_error_code) cmd_stop_trace(session); |
f2b3ef9f JG |
430 | switch (cmd_ret) { |
431 | case LTTNG_OK: | |
34f87583 JR |
432 | DBG("Successfully stopped session `%s` on behalf of trigger `%s`", |
433 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
434 | break; |
435 | case LTTNG_ERR_TRACE_ALREADY_STOPPED: | |
34f87583 JR |
436 | DBG("Attempted to stop session `%s` on behalf of trigger `%s` but it was already stopped", |
437 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
438 | break; |
439 | default: | |
34f87583 JR |
440 | WARN("Failed to stop session `%s` on behalf of trigger `%s`: %s", |
441 | session_name, get_trigger_name(work_item->trigger), | |
f2b3ef9f | 442 | lttng_strerror(-cmd_ret)); |
2d57482c | 443 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
444 | break; |
445 | } | |
446 | ||
635e0160 | 447 | error_unlock_session: |
f2b3ef9f JG |
448 | session_unlock(session); |
449 | session_put(session); | |
450 | error_unlock_list: | |
c9753f72 | 451 | rcu_read_unlock(); |
f2b3ef9f JG |
452 | session_unlock_list(); |
453 | end: | |
454 | return ret; | |
455 | } | |
456 | ||
2d57482c | 457 | static int action_executor_rotate_session_handler( |
f46376a1 | 458 | struct action_executor *executor __attribute__((unused)), |
f2b3ef9f | 459 | const struct action_work_item *work_item, |
72365501 | 460 | struct action_work_subitem *item) |
f2b3ef9f JG |
461 | { |
462 | int ret = 0; | |
463 | const char *session_name; | |
464 | enum lttng_action_status action_status; | |
465 | struct ltt_session *session; | |
466 | enum lttng_error_code cmd_ret; | |
72365501 | 467 | struct lttng_action *action = item->action; |
f2b3ef9f JG |
468 | |
469 | action_status = lttng_action_rotate_session_get_session_name( | |
470 | action, &session_name); | |
471 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
472 | ERR("Failed to get session name from `%s` action", | |
473 | get_action_name(action)); | |
474 | ret = -1; | |
475 | goto end; | |
476 | } | |
477 | ||
72365501 JR |
478 | /* |
479 | * Validate if, at the moment the action was queued, the target session | |
480 | * existed. If not, skip the action altogether. | |
481 | */ | |
482 | if (!item->context.session_id.is_set) { | |
4ec6f5b6 | 483 | DBG("Session `%s` was not present at the moment the work item was enqueued for `%s` action of trigger `%s`", |
72365501 JR |
484 | session_name, get_action_name(action), |
485 | get_trigger_name(work_item->trigger)); | |
486 | lttng_action_increase_execution_failure_count(action); | |
72365501 JR |
487 | goto end; |
488 | } | |
489 | ||
f2b3ef9f | 490 | session_lock_list(); |
c9753f72 | 491 | rcu_read_lock(); |
4a467a84 | 492 | session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id)); |
f2b3ef9f | 493 | if (!session) { |
34f87583 | 494 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`", |
f2b3ef9f | 495 | session_name, get_action_name(action), |
34f87583 | 496 | get_trigger_name(work_item->trigger)); |
2d57482c | 497 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
498 | goto error_unlock_list; |
499 | } | |
500 | ||
4a467a84 JR |
501 | session_lock(session); |
502 | if (session->destroyed) { | |
4ec6f5b6 | 503 | DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`", |
4a467a84 | 504 | session->name, session->id, |
72365501 JR |
505 | get_action_name(action), |
506 | get_trigger_name(work_item->trigger)); | |
4a467a84 | 507 | goto error_unlock_session; |
72365501 JR |
508 | } |
509 | ||
f2b3ef9f | 510 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { |
635e0160 | 511 | goto error_unlock_session; |
f2b3ef9f JG |
512 | } |
513 | ||
7966af57 | 514 | cmd_ret = (lttng_error_code) cmd_rotate_session(session, NULL, false, |
f2b3ef9f JG |
515 | LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED); |
516 | switch (cmd_ret) { | |
517 | case LTTNG_OK: | |
34f87583 JR |
518 | DBG("Successfully started rotation of session `%s` on behalf of trigger `%s`", |
519 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
520 | break; |
521 | case LTTNG_ERR_ROTATION_PENDING: | |
34f87583 JR |
522 | DBG("Attempted to start a rotation of session `%s` on behalf of trigger `%s` but a rotation is already ongoing", |
523 | session_name, get_trigger_name(work_item->trigger)); | |
2d57482c | 524 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
525 | break; |
526 | case LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP: | |
527 | case LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR: | |
34f87583 JR |
528 | 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", |
529 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
530 | break; |
531 | default: | |
34f87583 JR |
532 | WARN("Failed to start a rotation of session `%s` on behalf of trigger `%s`: %s", |
533 | session_name, get_trigger_name(work_item->trigger), | |
f2b3ef9f | 534 | lttng_strerror(-cmd_ret)); |
2d57482c | 535 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
536 | break; |
537 | } | |
538 | ||
635e0160 | 539 | error_unlock_session: |
f2b3ef9f JG |
540 | session_unlock(session); |
541 | session_put(session); | |
542 | error_unlock_list: | |
c9753f72 | 543 | rcu_read_unlock(); |
f2b3ef9f JG |
544 | session_unlock_list(); |
545 | end: | |
546 | return ret; | |
547 | } | |
548 | ||
2d57482c | 549 | static int action_executor_snapshot_session_handler( |
f46376a1 | 550 | struct action_executor *executor __attribute__((unused)), |
f2b3ef9f | 551 | const struct action_work_item *work_item, |
72365501 | 552 | struct action_work_subitem *item) |
f2b3ef9f JG |
553 | { |
554 | int ret = 0; | |
555 | const char *session_name; | |
556 | enum lttng_action_status action_status; | |
557 | struct ltt_session *session; | |
7966af57 | 558 | lttng_snapshot_output default_snapshot_output; |
f2b3ef9f JG |
559 | const struct lttng_snapshot_output *snapshot_output = |
560 | &default_snapshot_output; | |
561 | enum lttng_error_code cmd_ret; | |
72365501 JR |
562 | struct lttng_action *action = item->action; |
563 | ||
7966af57 SM |
564 | default_snapshot_output.max_size = UINT64_MAX; |
565 | ||
72365501 JR |
566 | /* |
567 | * Validate if, at the moment the action was queued, the target session | |
568 | * existed. If not, skip the action altogether. | |
569 | */ | |
570 | if (!item->context.session_id.is_set) { | |
4ec6f5b6 | 571 | DBG("Session was not present at the moment the work item was enqueued for `%s` action of trigger `%s`", |
42ef691e | 572 | get_action_name(action), |
72365501 JR |
573 | get_trigger_name(work_item->trigger)); |
574 | lttng_action_increase_execution_failure_count(action); | |
72365501 JR |
575 | goto end; |
576 | } | |
f2b3ef9f JG |
577 | |
578 | action_status = lttng_action_snapshot_session_get_session_name( | |
579 | action, &session_name); | |
580 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
581 | ERR("Failed to get session name from `%s` action", | |
582 | get_action_name(action)); | |
583 | ret = -1; | |
584 | goto end; | |
585 | } | |
586 | ||
587 | action_status = lttng_action_snapshot_session_get_output( | |
588 | action, &snapshot_output); | |
589 | if (action_status != LTTNG_ACTION_STATUS_OK && | |
590 | action_status != LTTNG_ACTION_STATUS_UNSET) { | |
591 | ERR("Failed to get output from `%s` action", | |
592 | get_action_name(action)); | |
593 | ret = -1; | |
594 | goto end; | |
595 | } | |
596 | ||
597 | session_lock_list(); | |
c9753f72 | 598 | rcu_read_lock(); |
4a467a84 | 599 | session = session_find_by_id(LTTNG_OPTIONAL_GET(item->context.session_id)); |
f2b3ef9f | 600 | if (!session) { |
ca46af4e | 601 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%s`", |
f2b3ef9f | 602 | session_name, get_action_name(action), |
ca46af4e | 603 | get_trigger_name(work_item->trigger)); |
2d57482c | 604 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
605 | goto error_unlock_list; |
606 | } | |
607 | ||
4a467a84 JR |
608 | session_lock(session); |
609 | if (session->destroyed) { | |
4ec6f5b6 | 610 | DBG("Session `%s` with id = %" PRIu64 " is flagged as destroyed. Skipping: action = `%s`, trigger = `%s`", |
4a467a84 | 611 | session->name, session->id, |
72365501 JR |
612 | get_action_name(action), |
613 | get_trigger_name(work_item->trigger)); | |
4a467a84 | 614 | goto error_unlock_session; |
72365501 | 615 | } |
f2b3ef9f | 616 | |
f2b3ef9f | 617 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { |
635e0160 | 618 | goto error_unlock_session; |
f2b3ef9f JG |
619 | } |
620 | ||
7966af57 | 621 | cmd_ret = (lttng_error_code) cmd_snapshot_record(session, snapshot_output, 0); |
f2b3ef9f JG |
622 | switch (cmd_ret) { |
623 | case LTTNG_OK: | |
34f87583 JR |
624 | DBG("Successfully recorded snapshot of session `%s` on behalf of trigger `%s`", |
625 | session_name, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
626 | break; |
627 | default: | |
34f87583 JR |
628 | WARN("Failed to record snapshot of session `%s` on behalf of trigger `%s`: %s", |
629 | session_name, get_trigger_name(work_item->trigger), | |
f2b3ef9f | 630 | lttng_strerror(-cmd_ret)); |
2d57482c | 631 | lttng_action_increase_execution_failure_count(action); |
f2b3ef9f JG |
632 | break; |
633 | } | |
634 | ||
635e0160 | 635 | error_unlock_session: |
f2b3ef9f JG |
636 | session_unlock(session); |
637 | session_put(session); | |
638 | error_unlock_list: | |
c9753f72 | 639 | rcu_read_unlock(); |
f2b3ef9f JG |
640 | session_unlock_list(); |
641 | end: | |
642 | return ret; | |
643 | } | |
644 | ||
f46376a1 MJ |
645 | static int action_executor_list_handler( |
646 | struct action_executor *executor __attribute__((unused)), | |
647 | const struct action_work_item *work_item __attribute__((unused)), | |
648 | struct action_work_subitem *item __attribute__((unused))) | |
f2b3ef9f | 649 | { |
7c2fae7c | 650 | ERR("Execution of a list action by the action executor should never occur"); |
72365501 | 651 | abort(); |
f2b3ef9f JG |
652 | } |
653 | ||
654 | static int action_executor_generic_handler(struct action_executor *executor, | |
655 | const struct action_work_item *work_item, | |
72365501 | 656 | struct action_work_subitem *item) |
f2b3ef9f | 657 | { |
2d57482c | 658 | int ret; |
72365501 | 659 | struct lttng_action *action = item->action; |
0e43bcbf JG |
660 | const enum lttng_action_type action_type = lttng_action_get_type(action); |
661 | ||
a0377dfe | 662 | LTTNG_ASSERT(action_type != LTTNG_ACTION_TYPE_UNKNOWN); |
0e43bcbf | 663 | |
2d57482c JR |
664 | lttng_action_increase_execution_request_count(action); |
665 | if (!lttng_action_should_execute(action)) { | |
666 | DBG("Policy prevented execution of action `%s` of trigger `%s` action work item %" PRIu64, | |
667 | get_action_name(action), | |
668 | get_trigger_name(work_item->trigger), | |
669 | work_item->id); | |
670 | ret = 0; | |
671 | goto end; | |
672 | } | |
673 | ||
674 | lttng_action_increase_execution_count(action); | |
2516f2d8 | 675 | DBG("Executing action `%s` of trigger `%s` action work item %" PRIu64, |
f2b3ef9f | 676 | get_action_name(action), |
34f87583 | 677 | get_trigger_name(work_item->trigger), |
f2b3ef9f | 678 | work_item->id); |
72365501 | 679 | ret = action_executors[action_type](executor, work_item, item); |
2d57482c JR |
680 | end: |
681 | return ret; | |
f2b3ef9f JG |
682 | } |
683 | ||
684 | static int action_work_item_execute(struct action_executor *executor, | |
685 | struct action_work_item *work_item) | |
686 | { | |
687 | int ret; | |
72365501 | 688 | size_t count, i; |
f2b3ef9f | 689 | |
34f87583 JR |
690 | DBG("Starting execution of action work item %" PRIu64 " of trigger `%s`", |
691 | work_item->id, get_trigger_name(work_item->trigger)); | |
72365501 | 692 | |
be65f802 | 693 | count = lttng_dynamic_array_get_count(&work_item->subitems); |
72365501 JR |
694 | for (i = 0; i < count; i++) { |
695 | struct action_work_subitem *item; | |
696 | ||
7966af57 | 697 | item = (action_work_subitem *) lttng_dynamic_array_get_element(&work_item->subitems, i); |
72365501 JR |
698 | ret = action_executor_generic_handler( |
699 | executor, work_item, item); | |
700 | if (ret) { | |
701 | goto end; | |
702 | } | |
703 | } | |
704 | end: | |
34f87583 JR |
705 | DBG("Completed execution of action work item %" PRIu64 " of trigger `%s`", |
706 | work_item->id, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
707 | return ret; |
708 | } | |
709 | ||
710 | static void action_work_item_destroy(struct action_work_item *work_item) | |
711 | { | |
712 | lttng_trigger_put(work_item->trigger); | |
713 | lttng_evaluation_destroy(work_item->evaluation); | |
714 | notification_client_list_put(work_item->client_list); | |
be65f802 | 715 | lttng_dynamic_array_reset(&work_item->subitems); |
f2b3ef9f JG |
716 | free(work_item); |
717 | } | |
718 | ||
719 | static void *action_executor_thread(void *_data) | |
720 | { | |
7966af57 | 721 | struct action_executor *executor = (action_executor *) _data; |
f2b3ef9f | 722 | |
a0377dfe | 723 | LTTNG_ASSERT(executor); |
f2b3ef9f | 724 | |
412d7227 SM |
725 | health_register(the_health_sessiond, |
726 | HEALTH_SESSIOND_TYPE_ACTION_EXECUTOR); | |
f2b3ef9f JG |
727 | |
728 | rcu_register_thread(); | |
729 | rcu_thread_online(); | |
730 | ||
731 | DBG("Entering work execution loop"); | |
732 | pthread_mutex_lock(&executor->work.lock); | |
733 | while (!executor->should_quit) { | |
da247508 | 734 | int ret = 0; |
f2b3ef9f JG |
735 | struct action_work_item *work_item; |
736 | ||
737 | health_code_update(); | |
738 | if (executor->work.pending_count == 0) { | |
739 | health_poll_entry(); | |
740 | DBG("No work items enqueued, entering wait"); | |
741 | pthread_cond_wait(&executor->work.cond, | |
742 | &executor->work.lock); | |
743 | DBG("Woke-up from wait"); | |
744 | health_poll_exit(); | |
745 | continue; | |
746 | } | |
747 | ||
0db0f8e0 | 748 | /* Pop item from front of the list with work lock held. */ |
f2b3ef9f JG |
749 | work_item = cds_list_first_entry(&executor->work.list, |
750 | struct action_work_item, list_node); | |
751 | cds_list_del(&work_item->list_node); | |
752 | executor->work.pending_count--; | |
753 | ||
754 | /* | |
755 | * Work can be performed without holding the work lock, | |
756 | * allowing new items to be queued. | |
757 | */ | |
758 | pthread_mutex_unlock(&executor->work.lock); | |
d2a28b27 JR |
759 | |
760 | /* Execute item only if a trigger is registered. */ | |
761 | lttng_trigger_lock(work_item->trigger); | |
762 | if (!lttng_trigger_is_registered(work_item->trigger)) { | |
763 | const char *trigger_name = NULL; | |
764 | uid_t trigger_owner_uid; | |
765 | enum lttng_trigger_status trigger_status; | |
766 | ||
0efb2ad7 | 767 | trigger_name = get_trigger_name(work_item->trigger); |
d2a28b27 JR |
768 | |
769 | trigger_status = lttng_trigger_get_owner_uid( | |
770 | work_item->trigger, &trigger_owner_uid); | |
a0377dfe | 771 | LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK); |
d2a28b27 | 772 | |
4ec6f5b6 | 773 | 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 |
774 | work_item->id, trigger_name, |
775 | (int) trigger_owner_uid); | |
776 | ret = 0; | |
777 | goto skip_execute; | |
778 | } | |
779 | ||
f2b3ef9f | 780 | ret = action_work_item_execute(executor, work_item); |
d2a28b27 JR |
781 | |
782 | skip_execute: | |
783 | lttng_trigger_unlock(work_item->trigger); | |
f2b3ef9f JG |
784 | action_work_item_destroy(work_item); |
785 | if (ret) { | |
786 | /* Fatal error. */ | |
787 | break; | |
788 | } | |
789 | ||
790 | health_code_update(); | |
791 | pthread_mutex_lock(&executor->work.lock); | |
792 | } | |
793 | ||
f5f5c54d JG |
794 | if (executor->should_quit) { |
795 | pthread_mutex_unlock(&executor->work.lock); | |
796 | } | |
f2b3ef9f JG |
797 | DBG("Left work execution loop"); |
798 | ||
799 | health_code_update(); | |
800 | ||
801 | rcu_thread_offline(); | |
802 | rcu_unregister_thread(); | |
412d7227 | 803 | health_unregister(the_health_sessiond); |
f2b3ef9f JG |
804 | |
805 | return NULL; | |
806 | } | |
807 | ||
808 | static bool shutdown_action_executor_thread(void *_data) | |
809 | { | |
7966af57 | 810 | struct action_executor *executor = (action_executor *) _data; |
f2b3ef9f | 811 | |
8db3acaf | 812 | pthread_mutex_lock(&executor->work.lock); |
f2b3ef9f JG |
813 | executor->should_quit = true; |
814 | pthread_cond_signal(&executor->work.cond); | |
8db3acaf | 815 | pthread_mutex_unlock(&executor->work.lock); |
f2b3ef9f JG |
816 | return true; |
817 | } | |
818 | ||
819 | static void clean_up_action_executor_thread(void *_data) | |
820 | { | |
7966af57 | 821 | struct action_executor *executor = (action_executor *) _data; |
f2b3ef9f | 822 | |
a0377dfe | 823 | LTTNG_ASSERT(cds_list_empty(&executor->work.list)); |
f2b3ef9f JG |
824 | |
825 | pthread_mutex_destroy(&executor->work.lock); | |
826 | pthread_cond_destroy(&executor->work.cond); | |
827 | free(executor); | |
828 | } | |
829 | ||
830 | struct action_executor *action_executor_create( | |
831 | struct notification_thread_handle *handle) | |
832 | { | |
64803277 | 833 | struct action_executor *executor = zmalloc<action_executor>(); |
f2b3ef9f JG |
834 | |
835 | if (!executor) { | |
836 | goto end; | |
837 | } | |
838 | ||
839 | CDS_INIT_LIST_HEAD(&executor->work.list); | |
840 | pthread_cond_init(&executor->work.cond, NULL); | |
841 | pthread_mutex_init(&executor->work.lock, NULL); | |
842 | executor->notification_thread_handle = handle; | |
843 | ||
844 | executor->thread = lttng_thread_create(THREAD_NAME, | |
845 | action_executor_thread, shutdown_action_executor_thread, | |
846 | clean_up_action_executor_thread, executor); | |
847 | end: | |
848 | return executor; | |
849 | } | |
850 | ||
851 | void action_executor_destroy(struct action_executor *executor) | |
852 | { | |
853 | struct action_work_item *work_item, *tmp; | |
854 | ||
855 | /* TODO Wait for work list to drain? */ | |
856 | lttng_thread_shutdown(executor->thread); | |
857 | pthread_mutex_lock(&executor->work.lock); | |
858 | if (executor->work.pending_count != 0) { | |
859 | WARN("%" PRIu64 | |
860 | " trigger action%s still queued for execution and will be discarded", | |
861 | executor->work.pending_count, | |
862 | executor->work.pending_count == 1 ? " is" : | |
863 | "s are"); | |
864 | } | |
865 | ||
866 | cds_list_for_each_entry_safe ( | |
867 | work_item, tmp, &executor->work.list, list_node) { | |
868 | WARN("Discarding action work item %" PRIu64 | |
34f87583 JR |
869 | " associated to trigger `%s`", |
870 | work_item->id, get_trigger_name(work_item->trigger)); | |
f2b3ef9f JG |
871 | cds_list_del(&work_item->list_node); |
872 | action_work_item_destroy(work_item); | |
873 | } | |
874 | pthread_mutex_unlock(&executor->work.lock); | |
875 | lttng_thread_put(executor->thread); | |
876 | } | |
877 | ||
878 | /* RCU read-lock must be held by the caller. */ | |
72365501 | 879 | enum action_executor_status action_executor_enqueue_trigger( |
f2b3ef9f JG |
880 | struct action_executor *executor, |
881 | struct lttng_trigger *trigger, | |
882 | struct lttng_evaluation *evaluation, | |
883 | const struct lttng_credentials *object_creds, | |
884 | struct notification_client_list *client_list) | |
885 | { | |
72365501 | 886 | int ret; |
f2b3ef9f JG |
887 | enum action_executor_status executor_status = ACTION_EXECUTOR_STATUS_OK; |
888 | const uint64_t work_item_id = executor->next_work_item_id++; | |
889 | struct action_work_item *work_item; | |
890 | bool signal = false; | |
72365501 | 891 | |
a0377dfe | 892 | LTTNG_ASSERT(trigger); |
48b7cdc2 | 893 | ASSERT_RCU_READ_LOCKED(); |
72365501 | 894 | |
f2b3ef9f JG |
895 | pthread_mutex_lock(&executor->work.lock); |
896 | /* Check for queue overflow. */ | |
897 | if (executor->work.pending_count >= MAX_QUEUED_WORK_COUNT) { | |
898 | /* Most likely spammy, remove if it is the case. */ | |
72365501 JR |
899 | DBG("Refusing to enqueue action for trigger (overflow): trigger name = `%s`, work item id = %" PRIu64, |
900 | get_trigger_name(trigger), work_item_id); | |
f2b3ef9f JG |
901 | executor_status = ACTION_EXECUTOR_STATUS_OVERFLOW; |
902 | goto error_unlock; | |
903 | } | |
904 | ||
64803277 | 905 | work_item = zmalloc<action_work_item>(); |
f2b3ef9f | 906 | if (!work_item) { |
4ec6f5b6 | 907 | PERROR("Failed to allocate action executor work item: trigger name = `%s`", |
34f87583 | 908 | get_trigger_name(trigger)); |
f2b3ef9f JG |
909 | executor_status = ACTION_EXECUTOR_STATUS_ERROR; |
910 | goto error_unlock; | |
911 | } | |
912 | ||
913 | lttng_trigger_get(trigger); | |
914 | if (client_list) { | |
915 | const bool reference_acquired = | |
916 | notification_client_list_get(client_list); | |
917 | ||
a0377dfe | 918 | LTTNG_ASSERT(reference_acquired); |
f2b3ef9f JG |
919 | } |
920 | ||
7966af57 SM |
921 | work_item->id = work_item_id; |
922 | work_item->trigger = trigger; | |
f2b3ef9f | 923 | |
7966af57 SM |
924 | /* Ownership transferred to the work item. */ |
925 | work_item->evaluation = evaluation; | |
f2b3ef9f | 926 | evaluation = NULL; |
be65f802 | 927 | |
7966af57 SM |
928 | work_item->client_list = client_list; |
929 | work_item->object_creds.is_set = !!object_creds; | |
930 | if (object_creds) { | |
931 | work_item->object_creds.value = *object_creds; | |
932 | } | |
933 | ||
934 | CDS_INIT_LIST_HEAD(&work_item->list_node); | |
935 | ||
be65f802 JG |
936 | /* Build the array of action work subitems for the passed trigger. */ |
937 | lttng_dynamic_array_init(&work_item->subitems, | |
938 | sizeof(struct action_work_subitem), | |
939 | action_work_subitem_destructor); | |
940 | ||
941 | ret = populate_subitem_array_from_trigger( | |
942 | trigger, &work_item->subitems); | |
943 | if (ret) { | |
944 | ERR("Failed to populate work item sub items on behalf of trigger: trigger name = `%s`", | |
945 | get_trigger_name(trigger)); | |
946 | executor_status = ACTION_EXECUTOR_STATUS_ERROR; | |
947 | goto error_unlock; | |
948 | } | |
949 | ||
f2b3ef9f JG |
950 | cds_list_add_tail(&work_item->list_node, &executor->work.list); |
951 | executor->work.pending_count++; | |
72365501 | 952 | DBG("Enqueued action for trigger: trigger name = `%s`, work item id = %" PRIu64, |
34f87583 | 953 | get_trigger_name(trigger), work_item_id); |
f2b3ef9f JG |
954 | signal = true; |
955 | ||
956 | error_unlock: | |
f2b3ef9f JG |
957 | if (signal) { |
958 | pthread_cond_signal(&executor->work.cond); | |
959 | } | |
960 | ||
be65f802 | 961 | pthread_mutex_unlock(&executor->work.lock); |
f2b3ef9f JG |
962 | lttng_evaluation_destroy(evaluation); |
963 | return executor_status; | |
964 | } | |
72365501 JR |
965 | |
966 | static int add_action_to_subitem_array(struct lttng_action *action, | |
967 | struct lttng_dynamic_array *subitems) | |
968 | { | |
da247508 | 969 | int ret = 0; |
72365501 JR |
970 | enum lttng_action_type type = lttng_action_get_type(action); |
971 | const char *session_name = NULL; | |
972 | enum lttng_action_status status; | |
973 | struct action_work_subitem subitem = { | |
974 | .action = NULL, | |
975 | .context = { | |
976 | .session_id = LTTNG_OPTIONAL_INIT_UNSET, | |
977 | }, | |
978 | }; | |
979 | ||
a0377dfe FD |
980 | LTTNG_ASSERT(action); |
981 | LTTNG_ASSERT(subitems); | |
72365501 | 982 | |
7c2fae7c | 983 | if (type == LTTNG_ACTION_TYPE_LIST) { |
72365501 JR |
984 | unsigned int count, i; |
985 | ||
702f26c8 | 986 | status = lttng_action_list_get_count(action, &count); |
a0377dfe | 987 | LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK); |
72365501 JR |
988 | |
989 | for (i = 0; i < count; i++) { | |
990 | struct lttng_action *inner_action = NULL; | |
991 | ||
702f26c8 | 992 | inner_action = lttng_action_list_borrow_mutable_at_index( |
72365501 | 993 | action, i); |
a0377dfe | 994 | LTTNG_ASSERT(inner_action); |
72365501 JR |
995 | ret = add_action_to_subitem_array( |
996 | inner_action, subitems); | |
997 | if (ret) { | |
998 | goto end; | |
999 | } | |
1000 | } | |
1001 | ||
1002 | /* | |
1003 | * Go directly to the end since there is no need to add the | |
7c2fae7c | 1004 | * list action by itself to the subitems array. |
72365501 JR |
1005 | */ |
1006 | goto end; | |
1007 | } | |
1008 | ||
1009 | /* Gather execution context. */ | |
1010 | switch (type) { | |
1011 | case LTTNG_ACTION_TYPE_NOTIFY: | |
1012 | break; | |
1013 | case LTTNG_ACTION_TYPE_START_SESSION: | |
1014 | status = lttng_action_start_session_get_session_name( | |
1015 | action, &session_name); | |
a0377dfe | 1016 | LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK); |
72365501 JR |
1017 | break; |
1018 | case LTTNG_ACTION_TYPE_STOP_SESSION: | |
1019 | status = lttng_action_stop_session_get_session_name( | |
1020 | action, &session_name); | |
a0377dfe | 1021 | LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK); |
72365501 JR |
1022 | break; |
1023 | case LTTNG_ACTION_TYPE_ROTATE_SESSION: | |
1024 | status = lttng_action_rotate_session_get_session_name( | |
1025 | action, &session_name); | |
a0377dfe | 1026 | LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK); |
72365501 JR |
1027 | break; |
1028 | case LTTNG_ACTION_TYPE_SNAPSHOT_SESSION: | |
1029 | status = lttng_action_snapshot_session_get_session_name( | |
1030 | action, &session_name); | |
a0377dfe | 1031 | LTTNG_ASSERT(status == LTTNG_ACTION_STATUS_OK); |
72365501 | 1032 | break; |
7c2fae7c | 1033 | case LTTNG_ACTION_TYPE_LIST: |
72365501 JR |
1034 | case LTTNG_ACTION_TYPE_UNKNOWN: |
1035 | /* Fallthrough */ | |
1036 | default: | |
1037 | abort(); | |
1038 | break; | |
1039 | } | |
1040 | ||
1041 | /* | |
1042 | * Fetch the session execution context info as needed. | |
1043 | * Note that we could decide to not add an action for which we know the | |
1044 | * execution will not happen (i.e no session exists for that name). For | |
1045 | * now we leave the decision to skip to the action executor for sake of | |
1046 | * simplicity and consistency. | |
1047 | */ | |
1048 | if (session_name != NULL) { | |
e1bbf989 | 1049 | uint64_t session_id; |
72365501 | 1050 | |
e1bbf989 JR |
1051 | /* |
1052 | * Instantaneous sampling of the session id if present. | |
1053 | * | |
1054 | * This method is preferred over `sessiond_find_by_name` then | |
1055 | * fetching the session'd id since `sessiond_find_by_name` | |
1056 | * requires the session list lock to be taken. | |
1057 | * | |
1058 | * Taking the session list lock can lead to a deadlock | |
1059 | * between the action executor and the notification thread | |
1060 | * (caller of add_action_to_subitem_array). It is okay if the | |
1061 | * session state changes between the enqueuing time and the | |
1062 | * execution time. The execution context is validated at | |
1063 | * execution time. | |
1064 | */ | |
1065 | if (sample_session_id_by_name(session_name, &session_id)) { | |
72365501 | 1066 | LTTNG_OPTIONAL_SET(&subitem.context.session_id, |
e1bbf989 | 1067 | session_id); |
72365501 | 1068 | } |
72365501 JR |
1069 | } |
1070 | ||
1071 | /* Get a reference to the action. */ | |
1072 | lttng_action_get(action); | |
1073 | subitem.action = action; | |
1074 | ||
1075 | ret = lttng_dynamic_array_add_element(subitems, &subitem); | |
1076 | if (ret) { | |
1077 | ERR("Failed to add work subitem to the subitem array"); | |
1078 | lttng_action_put(action); | |
1079 | ret = -1; | |
1080 | goto end; | |
1081 | } | |
1082 | ||
1083 | end: | |
1084 | return ret; | |
1085 | } | |
1086 | ||
1087 | static int populate_subitem_array_from_trigger(struct lttng_trigger *trigger, | |
1088 | struct lttng_dynamic_array *subitems) | |
1089 | { | |
1090 | struct lttng_action *action; | |
1091 | ||
1092 | action = lttng_trigger_get_action(trigger); | |
a0377dfe | 1093 | LTTNG_ASSERT(action); |
72365501 JR |
1094 | |
1095 | return add_action_to_subitem_array(action, subitems); | |
1096 | } |