- /* Deserialize trigger. */
- {
- struct lttng_payload_view view =
- lttng_payload_view_from_payload(
- &trigger_payload, 0, -1);
-
- if (lttng_trigger_create_from_payload(&view, &trigger) !=
- trigger_len) {
- ERR("Invalid trigger payload received in \"register trigger\" command");
- ret = LTTNG_ERR_INVALID_TRIGGER;
- goto end;
+ /*
+ * The bytecode generation also serves as a validation step for the
+ * bytecode expressions.
+ */
+ ret_code = lttng_trigger_generate_bytecode(trigger, cmd_creds);
+ if (ret_code != LTTNG_OK) {
+ ERR("Failed to generate bytecode of trigger: trigger name = '%s', trigger owner uid = %d, error code = %d",
+ trigger_name, (int) trigger_owner, ret_code);
+ goto end;
+ }
+
+ /*
+ * A reference to the trigger is acquired by the notification thread.
+ * It is safe to return the same trigger to the caller since it the
+ * other user holds a reference.
+ *
+ * The trigger is modified during the execution of the
+ * "register trigger" command. However, by the time the command returns,
+ * it is safe to use without any locking as its properties are
+ * immutable.
+ */
+ ret_code = notification_thread_command_register_trigger(notification_thread,
+ trigger);
+ if (ret_code != LTTNG_OK) {
+ ERR("Failed to register trigger to notification thread: trigger name = '%s', trigger owner uid = %d, error code = %d",
+ trigger_name, (int) trigger_owner, ret_code);
+ goto end_notification_thread;
+ }
+
+ ret_code = trigger_modifies_event_notifier(trigger, &must_update_event_notifier);
+ if (ret_code != LTTNG_OK) {
+ ERR("Failed to determine if event modifies event notifiers: trigger name = '%s', trigger owner uid = %d, error code = %d",
+ trigger_name, (int) trigger_owner, ret_code);
+ goto end_notification_thread;
+ }
+
+ /*
+ * Synchronize tracers if the trigger adds an event notifier.
+ */
+ if (must_update_event_notifier) {
+ if (lttng_trigger_get_underlying_domain_type_restriction(
+ trigger) == LTTNG_DOMAIN_KERNEL) {
+
+ ret_code = kernel_register_event_notifier(
+ trigger, cmd_creds);
+ if (ret_code != LTTNG_OK) {
+ const enum lttng_error_code notif_thread_unregister_ret =
+ notification_thread_command_unregister_trigger(
+ notification_thread,
+ trigger);
+
+ if (notif_thread_unregister_ret != LTTNG_OK) {
+ /* Return the original error code. */
+ ERR("Failed to unregister trigger from notification thread during error recovery: trigger name = '%s', trigger owner uid = %d, error code = %d",
+ trigger_name,
+ (int) trigger_owner,
+ ret_code);
+ }
+
+ goto end;
+ }
+ } else {
+ ust_app_global_update_all_event_notifier_rules();