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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 | ||
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" | |
15 | #include <common/macros.h> | |
16 | #include <common/optional.h> | |
17 | #include <lttng/action/action-internal.h> | |
18 | #include <lttng/action/group.h> | |
19 | #include <lttng/action/notify.h> | |
20 | #include <lttng/action/rotate-session.h> | |
21 | #include <lttng/action/snapshot-session.h> | |
22 | #include <lttng/action/start-session.h> | |
23 | #include <lttng/action/stop-session.h> | |
24 | #include <lttng/condition/evaluation.h> | |
25 | #include <lttng/lttng-error.h> | |
26 | #include <lttng/trigger/trigger-internal.h> | |
27 | #include <pthread.h> | |
28 | #include <stdbool.h> | |
29 | #include <stddef.h> | |
30 | #include <urcu/list.h> | |
31 | ||
32 | #define THREAD_NAME "Action Executor" | |
33 | #define MAX_QUEUED_WORK_COUNT 8192 | |
34 | ||
35 | struct action_work_item { | |
36 | uint64_t id; | |
37 | struct lttng_trigger *trigger; | |
38 | struct lttng_evaluation *evaluation; | |
39 | struct notification_client_list *client_list; | |
40 | LTTNG_OPTIONAL(struct lttng_credentials) object_creds; | |
41 | struct cds_list_head list_node; | |
42 | }; | |
43 | ||
44 | struct action_executor { | |
45 | struct lttng_thread *thread; | |
46 | struct notification_thread_handle *notification_thread_handle; | |
47 | struct { | |
48 | uint64_t pending_count; | |
49 | struct cds_list_head list; | |
50 | pthread_cond_t cond; | |
51 | pthread_mutex_t lock; | |
52 | } work; | |
53 | bool should_quit; | |
54 | uint64_t next_work_item_id; | |
55 | }; | |
56 | ||
57 | /* | |
58 | * Only return non-zero on a fatal error that should shut down the action | |
59 | * executor. | |
60 | */ | |
61 | typedef int (*action_executor_handler)(struct action_executor *executor, | |
62 | const struct action_work_item *, | |
63 | const struct lttng_action *action); | |
64 | ||
65 | static int action_executor_notify_handler(struct action_executor *executor, | |
66 | const struct action_work_item *, | |
67 | const struct lttng_action *); | |
68 | static int action_executor_start_session_handler(struct action_executor *executor, | |
69 | const struct action_work_item *, | |
70 | const struct lttng_action *); | |
71 | static int action_executor_stop_session_handler(struct action_executor *executor, | |
72 | const struct action_work_item *, | |
73 | const struct lttng_action *); | |
74 | static int action_executor_rotate_session_handler(struct action_executor *executor, | |
75 | const struct action_work_item *, | |
76 | const struct lttng_action *); | |
77 | static int action_executor_snapshot_session_handler(struct action_executor *executor, | |
78 | const struct action_work_item *, | |
79 | const struct lttng_action *); | |
80 | static int action_executor_group_handler(struct action_executor *executor, | |
81 | const struct action_work_item *, | |
82 | const struct lttng_action *); | |
83 | static int action_executor_generic_handler(struct action_executor *executor, | |
84 | const struct action_work_item *, | |
85 | const struct lttng_action *); | |
86 | ||
87 | static const action_executor_handler action_executors[] = { | |
88 | [LTTNG_ACTION_TYPE_NOTIFY] = action_executor_notify_handler, | |
89 | [LTTNG_ACTION_TYPE_START_SESSION] = action_executor_start_session_handler, | |
90 | [LTTNG_ACTION_TYPE_STOP_SESSION] = action_executor_stop_session_handler, | |
91 | [LTTNG_ACTION_TYPE_ROTATE_SESSION] = action_executor_rotate_session_handler, | |
92 | [LTTNG_ACTION_TYPE_SNAPSHOT_SESSION] = action_executor_snapshot_session_handler, | |
93 | [LTTNG_ACTION_TYPE_GROUP] = action_executor_group_handler, | |
94 | }; | |
95 | ||
96 | static const char *action_type_names[] = { | |
97 | [LTTNG_ACTION_TYPE_NOTIFY] = "Notify", | |
98 | [LTTNG_ACTION_TYPE_START_SESSION] = "Start session", | |
99 | [LTTNG_ACTION_TYPE_STOP_SESSION] = "Stop session", | |
100 | [LTTNG_ACTION_TYPE_ROTATE_SESSION] = "Rotate session", | |
101 | [LTTNG_ACTION_TYPE_SNAPSHOT_SESSION] = "Snapshot session", | |
102 | [LTTNG_ACTION_TYPE_GROUP] = "Group", | |
103 | }; | |
104 | ||
105 | static const char *get_action_name(const struct lttng_action *action) | |
106 | { | |
17182cfd | 107 | return action_type_names[lttng_action_get_type(action)]; |
f2b3ef9f JG |
108 | } |
109 | ||
110 | /* Check if this trigger allowed to interect with a given session. */ | |
111 | static bool is_trigger_allowed_for_session(const struct lttng_trigger *trigger, | |
112 | struct ltt_session *session) | |
113 | { | |
114 | bool is_allowed = false; | |
115 | const struct lttng_credentials session_creds = { | |
116 | .uid = session->uid, | |
117 | .gid = session->gid, | |
118 | }; | |
119 | /* Can never be NULL. */ | |
120 | const struct lttng_credentials *trigger_creds = | |
121 | lttng_trigger_get_credentials(trigger); | |
122 | ||
123 | is_allowed = (trigger_creds->uid == session_creds.uid) || | |
124 | (trigger_creds->uid == 0); | |
125 | if (!is_allowed) { | |
126 | WARN("Trigger is not allowed to interact with session `%s`: session uid = %ld, session gid = %ld, trigger uid = %ld, trigger gid = %ld", | |
127 | session->name, | |
128 | (long int) session->uid, | |
129 | (long int) session->gid, | |
130 | (long int) trigger_creds->uid, | |
131 | (long int) trigger_creds->gid); | |
132 | } | |
133 | ||
134 | return is_allowed; | |
135 | } | |
136 | ||
137 | static int client_handle_transmission_status( | |
138 | struct notification_client *client, | |
139 | enum client_transmission_status status, | |
140 | void *user_data) | |
141 | { | |
142 | int ret = 0; | |
143 | struct action_executor *executor = user_data; | |
144 | bool update_communication = true; | |
145 | ||
f2b3ef9f JG |
146 | switch (status) { |
147 | case CLIENT_TRANSMISSION_STATUS_COMPLETE: | |
148 | DBG("Successfully sent full notification to client, client_id = %" PRIu64, | |
149 | client->id); | |
150 | update_communication = false; | |
151 | break; | |
152 | case CLIENT_TRANSMISSION_STATUS_QUEUED: | |
153 | DBG("Queued notification in client outgoing buffer, client_id = %" PRIu64, | |
154 | client->id); | |
155 | break; | |
156 | case CLIENT_TRANSMISSION_STATUS_FAIL: | |
157 | DBG("Communication error occurred while sending notification to client, client_id = %" PRIu64, | |
158 | client->id); | |
f2b3ef9f JG |
159 | break; |
160 | default: | |
161 | ERR("Fatal error encoutered while sending notification to client, client_id = %" PRIu64, | |
162 | client->id); | |
f2b3ef9f JG |
163 | ret = -1; |
164 | goto end; | |
165 | } | |
166 | ||
167 | if (!update_communication) { | |
168 | goto end; | |
169 | } | |
170 | ||
6c24d3fd | 171 | /* Safe to read client's id without locking as it is immutable. */ |
f2b3ef9f JG |
172 | ret = notification_thread_client_communication_update( |
173 | executor->notification_thread_handle, client->id, | |
174 | status); | |
175 | end: | |
176 | return ret; | |
177 | } | |
178 | ||
179 | static int action_executor_notify_handler(struct action_executor *executor, | |
180 | const struct action_work_item *work_item, | |
181 | const struct lttng_action *action) | |
182 | { | |
183 | return notification_client_list_send_evaluation(work_item->client_list, | |
184 | lttng_trigger_get_const_condition(work_item->trigger), | |
185 | work_item->evaluation, | |
186 | lttng_trigger_get_credentials(work_item->trigger), | |
187 | LTTNG_OPTIONAL_GET_PTR(work_item->object_creds), | |
188 | client_handle_transmission_status, | |
189 | executor); | |
190 | } | |
191 | ||
192 | static int action_executor_start_session_handler(struct action_executor *executor, | |
193 | const struct action_work_item *work_item, | |
194 | const struct lttng_action *action) | |
195 | { | |
196 | int ret = 0; | |
197 | const char *session_name; | |
198 | enum lttng_action_status action_status; | |
199 | struct ltt_session *session; | |
200 | enum lttng_error_code cmd_ret; | |
201 | ||
202 | action_status = lttng_action_start_session_get_session_name( | |
203 | action, &session_name); | |
204 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
205 | ERR("Failed to get session name from `%s` action", | |
206 | get_action_name(action)); | |
207 | ret = -1; | |
208 | goto end; | |
209 | } | |
210 | ||
211 | session_lock_list(); | |
212 | session = session_find_by_name(session_name); | |
213 | if (!session) { | |
214 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%p`", | |
215 | session_name, get_action_name(action), | |
216 | work_item->trigger); | |
217 | goto error_unlock_list; | |
218 | } | |
219 | ||
220 | session_lock(session); | |
221 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { | |
222 | goto error_dispose_session; | |
223 | } | |
224 | ||
225 | cmd_ret = cmd_start_trace(session); | |
226 | switch (cmd_ret) { | |
227 | case LTTNG_OK: | |
228 | DBG("Successfully started session `%s` on behalf of trigger `%p`", | |
229 | session_name, work_item->trigger); | |
230 | break; | |
231 | case LTTNG_ERR_TRACE_ALREADY_STARTED: | |
232 | DBG("Attempted to start session `%s` on behalf of trigger `%p` but it was already started", | |
233 | session_name, work_item->trigger); | |
234 | break; | |
235 | default: | |
236 | WARN("Failed to start session `%s` on behalf of trigger `%p`: %s", | |
237 | session_name, work_item->trigger, | |
238 | lttng_strerror(-cmd_ret)); | |
239 | break; | |
240 | } | |
241 | ||
242 | error_dispose_session: | |
243 | session_unlock(session); | |
244 | session_put(session); | |
245 | error_unlock_list: | |
246 | session_unlock_list(); | |
247 | end: | |
248 | return ret; | |
249 | } | |
250 | ||
251 | static int action_executor_stop_session_handler(struct action_executor *executor, | |
252 | const struct action_work_item *work_item, | |
253 | const struct lttng_action *action) | |
254 | { | |
255 | int ret = 0; | |
256 | const char *session_name; | |
257 | enum lttng_action_status action_status; | |
258 | struct ltt_session *session; | |
259 | enum lttng_error_code cmd_ret; | |
260 | ||
261 | action_status = lttng_action_stop_session_get_session_name( | |
262 | action, &session_name); | |
263 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
264 | ERR("Failed to get session name from `%s` action", | |
265 | get_action_name(action)); | |
266 | ret = -1; | |
267 | goto end; | |
268 | } | |
269 | ||
270 | session_lock_list(); | |
271 | session = session_find_by_name(session_name); | |
272 | if (!session) { | |
273 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%p`", | |
274 | session_name, get_action_name(action), | |
275 | work_item->trigger); | |
276 | goto error_unlock_list; | |
277 | } | |
278 | ||
279 | session_lock(session); | |
280 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { | |
281 | goto error_dispose_session; | |
282 | } | |
283 | ||
284 | cmd_ret = cmd_stop_trace(session); | |
285 | switch (cmd_ret) { | |
286 | case LTTNG_OK: | |
287 | DBG("Successfully stopped session `%s` on behalf of trigger `%p`", | |
288 | session_name, work_item->trigger); | |
289 | break; | |
290 | case LTTNG_ERR_TRACE_ALREADY_STOPPED: | |
291 | DBG("Attempted to stop session `%s` on behalf of trigger `%p` but it was already stopped", | |
292 | session_name, work_item->trigger); | |
293 | break; | |
294 | default: | |
295 | WARN("Failed to stop session `%s` on behalf of trigger `%p`: %s", | |
296 | session_name, work_item->trigger, | |
297 | lttng_strerror(-cmd_ret)); | |
298 | break; | |
299 | } | |
300 | ||
301 | error_dispose_session: | |
302 | session_unlock(session); | |
303 | session_put(session); | |
304 | error_unlock_list: | |
305 | session_unlock_list(); | |
306 | end: | |
307 | return ret; | |
308 | } | |
309 | ||
310 | static int action_executor_rotate_session_handler(struct action_executor *executor, | |
311 | const struct action_work_item *work_item, | |
312 | const struct lttng_action *action) | |
313 | { | |
314 | int ret = 0; | |
315 | const char *session_name; | |
316 | enum lttng_action_status action_status; | |
317 | struct ltt_session *session; | |
318 | enum lttng_error_code cmd_ret; | |
319 | ||
320 | action_status = lttng_action_rotate_session_get_session_name( | |
321 | action, &session_name); | |
322 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
323 | ERR("Failed to get session name from `%s` action", | |
324 | get_action_name(action)); | |
325 | ret = -1; | |
326 | goto end; | |
327 | } | |
328 | ||
329 | session_lock_list(); | |
330 | session = session_find_by_name(session_name); | |
331 | if (!session) { | |
332 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%p`", | |
333 | session_name, get_action_name(action), | |
334 | work_item->trigger); | |
335 | goto error_unlock_list; | |
336 | } | |
337 | ||
338 | session_lock(session); | |
339 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { | |
340 | goto error_dispose_session; | |
341 | } | |
342 | ||
343 | cmd_ret = cmd_rotate_session(session, NULL, false, | |
344 | LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED); | |
345 | switch (cmd_ret) { | |
346 | case LTTNG_OK: | |
347 | DBG("Successfully started rotation of session `%s` on behalf of trigger `%p`", | |
348 | session_name, work_item->trigger); | |
349 | break; | |
350 | case LTTNG_ERR_ROTATION_PENDING: | |
351 | DBG("Attempted to start a rotation of session `%s` on behalf of trigger `%p` but a rotation is already ongoing", | |
352 | session_name, work_item->trigger); | |
353 | break; | |
354 | case LTTNG_ERR_ROTATION_MULTIPLE_AFTER_STOP: | |
355 | case LTTNG_ERR_ROTATION_AFTER_STOP_CLEAR: | |
356 | DBG("Attempted to start a rotation of session `%s` on behalf of trigger `%p` but a rotation has already been completed since the last stop or clear", | |
357 | session_name, work_item->trigger); | |
358 | break; | |
359 | default: | |
360 | WARN("Failed to start a rotation of session `%s` on behalf of trigger `%p`: %s", | |
361 | session_name, work_item->trigger, | |
362 | lttng_strerror(-cmd_ret)); | |
363 | break; | |
364 | } | |
365 | ||
366 | error_dispose_session: | |
367 | session_unlock(session); | |
368 | session_put(session); | |
369 | error_unlock_list: | |
370 | session_unlock_list(); | |
371 | end: | |
372 | return ret; | |
373 | } | |
374 | ||
375 | static int action_executor_snapshot_session_handler(struct action_executor *executor, | |
376 | const struct action_work_item *work_item, | |
377 | const struct lttng_action *action) | |
378 | { | |
379 | int ret = 0; | |
380 | const char *session_name; | |
381 | enum lttng_action_status action_status; | |
382 | struct ltt_session *session; | |
383 | const struct lttng_snapshot_output default_snapshot_output = { | |
384 | .max_size = UINT64_MAX, | |
385 | }; | |
386 | const struct lttng_snapshot_output *snapshot_output = | |
387 | &default_snapshot_output; | |
388 | enum lttng_error_code cmd_ret; | |
389 | ||
390 | action_status = lttng_action_snapshot_session_get_session_name( | |
391 | action, &session_name); | |
392 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
393 | ERR("Failed to get session name from `%s` action", | |
394 | get_action_name(action)); | |
395 | ret = -1; | |
396 | goto end; | |
397 | } | |
398 | ||
399 | action_status = lttng_action_snapshot_session_get_output( | |
400 | action, &snapshot_output); | |
401 | if (action_status != LTTNG_ACTION_STATUS_OK && | |
402 | action_status != LTTNG_ACTION_STATUS_UNSET) { | |
403 | ERR("Failed to get output from `%s` action", | |
404 | get_action_name(action)); | |
405 | ret = -1; | |
406 | goto end; | |
407 | } | |
408 | ||
409 | session_lock_list(); | |
410 | session = session_find_by_name(session_name); | |
411 | if (!session) { | |
412 | DBG("Failed to find session `%s` by name while executing `%s` action of trigger `%p`", | |
413 | session_name, get_action_name(action), | |
414 | work_item->trigger); | |
415 | goto error_unlock_list; | |
416 | } | |
417 | ||
418 | ||
419 | session_lock(session); | |
420 | if (!is_trigger_allowed_for_session(work_item->trigger, session)) { | |
421 | goto error_dispose_session; | |
422 | } | |
423 | ||
424 | cmd_ret = cmd_snapshot_record(session, snapshot_output, 0); | |
425 | switch (cmd_ret) { | |
426 | case LTTNG_OK: | |
427 | DBG("Successfully recorded snapshot of session `%s` on behalf of trigger `%p`", | |
428 | session_name, work_item->trigger); | |
429 | break; | |
430 | default: | |
431 | WARN("Failed to record snapshot of session `%s` on behalf of trigger `%p`: %s", | |
432 | session_name, work_item->trigger, | |
433 | lttng_strerror(-cmd_ret)); | |
434 | break; | |
435 | } | |
436 | ||
437 | error_dispose_session: | |
438 | session_unlock(session); | |
439 | session_put(session); | |
440 | error_unlock_list: | |
441 | session_unlock_list(); | |
442 | end: | |
443 | return ret; | |
444 | } | |
445 | ||
446 | static int action_executor_group_handler(struct action_executor *executor, | |
447 | const struct action_work_item *work_item, | |
448 | const struct lttng_action *action_group) | |
449 | { | |
450 | int ret = 0; | |
451 | unsigned int i, count; | |
452 | enum lttng_action_status action_status; | |
453 | ||
454 | action_status = lttng_action_group_get_count(action_group, &count); | |
455 | if (action_status != LTTNG_ACTION_STATUS_OK) { | |
456 | /* Fatal error. */ | |
457 | ERR("Failed to get count of action in action group"); | |
458 | ret = -1; | |
459 | goto end; | |
460 | } | |
461 | ||
462 | DBG("Action group has %u action%s", count, count != 1 ? "s" : ""); | |
463 | for (i = 0; i < count; i++) { | |
464 | const struct lttng_action *action = | |
465 | lttng_action_group_get_at_index( | |
466 | action_group, i); | |
467 | ||
468 | ret = action_executor_generic_handler( | |
469 | executor, work_item, action); | |
470 | if (ret) { | |
471 | ERR("Stopping the execution of the action group of trigger `%p` following a fatal error", | |
472 | work_item->trigger); | |
473 | goto end; | |
474 | } | |
475 | } | |
476 | end: | |
477 | return ret; | |
478 | } | |
479 | ||
480 | static int action_executor_generic_handler(struct action_executor *executor, | |
481 | const struct action_work_item *work_item, | |
482 | const struct lttng_action *action) | |
483 | { | |
484 | DBG("Executing action `%s` of trigger `%p` action work item %" PRIu64, | |
485 | get_action_name(action), | |
486 | work_item->trigger, | |
487 | work_item->id); | |
488 | ||
17182cfd | 489 | return action_executors[lttng_action_get_type(action)]( |
f2b3ef9f JG |
490 | executor, work_item, action); |
491 | } | |
492 | ||
493 | static int action_work_item_execute(struct action_executor *executor, | |
494 | struct action_work_item *work_item) | |
495 | { | |
496 | int ret; | |
497 | const struct lttng_action *action = | |
498 | lttng_trigger_get_const_action(work_item->trigger); | |
499 | ||
500 | DBG("Starting execution of action work item %" PRIu64 " of trigger `%p`", | |
501 | work_item->id, work_item->trigger); | |
502 | ret = action_executor_generic_handler(executor, work_item, action); | |
503 | DBG("Completed execution of action work item %" PRIu64 " of trigger `%p`", | |
504 | work_item->id, work_item->trigger); | |
505 | return ret; | |
506 | } | |
507 | ||
508 | static void action_work_item_destroy(struct action_work_item *work_item) | |
509 | { | |
510 | lttng_trigger_put(work_item->trigger); | |
511 | lttng_evaluation_destroy(work_item->evaluation); | |
512 | notification_client_list_put(work_item->client_list); | |
513 | free(work_item); | |
514 | } | |
515 | ||
516 | static void *action_executor_thread(void *_data) | |
517 | { | |
518 | struct action_executor *executor = _data; | |
519 | ||
520 | assert(executor); | |
521 | ||
522 | health_register(health_sessiond, HEALTH_SESSIOND_TYPE_ACTION_EXECUTOR); | |
523 | ||
524 | rcu_register_thread(); | |
525 | rcu_thread_online(); | |
526 | ||
527 | DBG("Entering work execution loop"); | |
528 | pthread_mutex_lock(&executor->work.lock); | |
529 | while (!executor->should_quit) { | |
530 | int ret; | |
531 | struct action_work_item *work_item; | |
532 | ||
533 | health_code_update(); | |
534 | if (executor->work.pending_count == 0) { | |
535 | health_poll_entry(); | |
536 | DBG("No work items enqueued, entering wait"); | |
537 | pthread_cond_wait(&executor->work.cond, | |
538 | &executor->work.lock); | |
539 | DBG("Woke-up from wait"); | |
540 | health_poll_exit(); | |
541 | continue; | |
542 | } | |
543 | ||
544 | /* Pop item from front of the listwith work lock held. */ | |
545 | work_item = cds_list_first_entry(&executor->work.list, | |
546 | struct action_work_item, list_node); | |
547 | cds_list_del(&work_item->list_node); | |
548 | executor->work.pending_count--; | |
549 | ||
550 | /* | |
551 | * Work can be performed without holding the work lock, | |
552 | * allowing new items to be queued. | |
553 | */ | |
554 | pthread_mutex_unlock(&executor->work.lock); | |
555 | ret = action_work_item_execute(executor, work_item); | |
556 | action_work_item_destroy(work_item); | |
557 | if (ret) { | |
558 | /* Fatal error. */ | |
559 | break; | |
560 | } | |
561 | ||
562 | health_code_update(); | |
563 | pthread_mutex_lock(&executor->work.lock); | |
564 | } | |
565 | ||
f5f5c54d JG |
566 | if (executor->should_quit) { |
567 | pthread_mutex_unlock(&executor->work.lock); | |
568 | } | |
f2b3ef9f JG |
569 | DBG("Left work execution loop"); |
570 | ||
571 | health_code_update(); | |
572 | ||
573 | rcu_thread_offline(); | |
574 | rcu_unregister_thread(); | |
575 | health_unregister(health_sessiond); | |
576 | ||
577 | return NULL; | |
578 | } | |
579 | ||
580 | static bool shutdown_action_executor_thread(void *_data) | |
581 | { | |
582 | struct action_executor *executor = _data; | |
583 | ||
584 | executor->should_quit = true; | |
585 | pthread_cond_signal(&executor->work.cond); | |
586 | return true; | |
587 | } | |
588 | ||
589 | static void clean_up_action_executor_thread(void *_data) | |
590 | { | |
591 | struct action_executor *executor = _data; | |
592 | ||
593 | assert(cds_list_empty(&executor->work.list)); | |
594 | ||
595 | pthread_mutex_destroy(&executor->work.lock); | |
596 | pthread_cond_destroy(&executor->work.cond); | |
597 | free(executor); | |
598 | } | |
599 | ||
600 | struct action_executor *action_executor_create( | |
601 | struct notification_thread_handle *handle) | |
602 | { | |
603 | struct action_executor *executor = zmalloc(sizeof(*executor)); | |
604 | ||
605 | if (!executor) { | |
606 | goto end; | |
607 | } | |
608 | ||
609 | CDS_INIT_LIST_HEAD(&executor->work.list); | |
610 | pthread_cond_init(&executor->work.cond, NULL); | |
611 | pthread_mutex_init(&executor->work.lock, NULL); | |
612 | executor->notification_thread_handle = handle; | |
613 | ||
614 | executor->thread = lttng_thread_create(THREAD_NAME, | |
615 | action_executor_thread, shutdown_action_executor_thread, | |
616 | clean_up_action_executor_thread, executor); | |
617 | end: | |
618 | return executor; | |
619 | } | |
620 | ||
621 | void action_executor_destroy(struct action_executor *executor) | |
622 | { | |
623 | struct action_work_item *work_item, *tmp; | |
624 | ||
625 | /* TODO Wait for work list to drain? */ | |
626 | lttng_thread_shutdown(executor->thread); | |
627 | pthread_mutex_lock(&executor->work.lock); | |
628 | if (executor->work.pending_count != 0) { | |
629 | WARN("%" PRIu64 | |
630 | " trigger action%s still queued for execution and will be discarded", | |
631 | executor->work.pending_count, | |
632 | executor->work.pending_count == 1 ? " is" : | |
633 | "s are"); | |
634 | } | |
635 | ||
636 | cds_list_for_each_entry_safe ( | |
637 | work_item, tmp, &executor->work.list, list_node) { | |
638 | WARN("Discarding action work item %" PRIu64 | |
639 | " associated to trigger `%p`", | |
640 | work_item->id, work_item->trigger); | |
641 | cds_list_del(&work_item->list_node); | |
642 | action_work_item_destroy(work_item); | |
643 | } | |
644 | pthread_mutex_unlock(&executor->work.lock); | |
645 | lttng_thread_put(executor->thread); | |
646 | } | |
647 | ||
648 | /* RCU read-lock must be held by the caller. */ | |
649 | enum action_executor_status action_executor_enqueue( | |
650 | struct action_executor *executor, | |
651 | struct lttng_trigger *trigger, | |
652 | struct lttng_evaluation *evaluation, | |
653 | const struct lttng_credentials *object_creds, | |
654 | struct notification_client_list *client_list) | |
655 | { | |
656 | enum action_executor_status executor_status = ACTION_EXECUTOR_STATUS_OK; | |
657 | const uint64_t work_item_id = executor->next_work_item_id++; | |
658 | struct action_work_item *work_item; | |
659 | bool signal = false; | |
660 | ||
661 | pthread_mutex_lock(&executor->work.lock); | |
662 | /* Check for queue overflow. */ | |
663 | if (executor->work.pending_count >= MAX_QUEUED_WORK_COUNT) { | |
664 | /* Most likely spammy, remove if it is the case. */ | |
665 | DBG("Refusing to enqueue action for trigger `%p` as work item %" PRIu64 | |
666 | " (overflow)", | |
667 | trigger, work_item_id); | |
668 | executor_status = ACTION_EXECUTOR_STATUS_OVERFLOW; | |
669 | goto error_unlock; | |
670 | } | |
671 | ||
672 | work_item = zmalloc(sizeof(*work_item)); | |
673 | if (!work_item) { | |
674 | PERROR("Failed to allocate action executor work item on behalf of trigger `%p`", | |
675 | trigger); | |
676 | executor_status = ACTION_EXECUTOR_STATUS_ERROR; | |
677 | goto error_unlock; | |
678 | } | |
679 | ||
680 | lttng_trigger_get(trigger); | |
681 | if (client_list) { | |
682 | const bool reference_acquired = | |
683 | notification_client_list_get(client_list); | |
684 | ||
685 | assert(reference_acquired); | |
686 | } | |
687 | ||
688 | *work_item = (typeof(*work_item)){ | |
689 | .id = work_item_id, | |
690 | .trigger = trigger, | |
691 | /* Ownership transferred to the work item. */ | |
692 | .evaluation = evaluation, | |
693 | .object_creds = { | |
694 | .is_set = !!object_creds, | |
695 | .value = object_creds ? *object_creds : | |
696 | (typeof(work_item->object_creds.value)) {}, | |
697 | }, | |
698 | .client_list = client_list, | |
699 | .list_node = CDS_LIST_HEAD_INIT(work_item->list_node), | |
700 | }; | |
701 | ||
702 | evaluation = NULL; | |
703 | cds_list_add_tail(&work_item->list_node, &executor->work.list); | |
704 | executor->work.pending_count++; | |
705 | DBG("Enqueued action for trigger `%p` as work item %" PRIu64, | |
706 | trigger, work_item_id); | |
707 | signal = true; | |
708 | ||
709 | error_unlock: | |
710 | pthread_mutex_unlock(&executor->work.lock); | |
711 | if (signal) { | |
712 | pthread_cond_signal(&executor->work.cond); | |
713 | } | |
714 | ||
715 | lttng_evaluation_destroy(evaluation); | |
716 | return executor_status; | |
717 | } |