X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fnotification-thread-events.c;h=90fdadd61280bc2452063931ad1c7ca1fc837f8b;hb=5c5373c3cbfebddb0068fe13600766bb381048da;hp=6d153f16d84cd715205ada63b64c9d1eaadf64cd;hpb=65f649784e948615ec369db9eba40847a75ccaf2;p=lttng-tools.git diff --git a/src/bin/lttng-sessiond/notification-thread-events.c b/src/bin/lttng-sessiond/notification-thread-events.c index 6d153f16d..90fdadd61 100644 --- a/src/bin/lttng-sessiond/notification-thread-events.c +++ b/src/bin/lttng-sessiond/notification-thread-events.c @@ -353,6 +353,8 @@ const char *notification_command_type_str( return "REMOVE_TRACER_EVENT_SOURCE"; case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS: return "LIST_TRIGGERS"; + case NOTIFICATION_COMMAND_TYPE_GET_TRIGGER: + return "GET_TRIGGER"; case NOTIFICATION_COMMAND_TYPE_QUIT: return "QUIT"; case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE: @@ -1089,6 +1091,7 @@ int notification_thread_client_subscribe(struct notification_client *client, struct notification_client_list *client_list = NULL; struct lttng_condition_list_element *condition_list_element = NULL; struct notification_client_list_element *client_list_element = NULL; + struct lttng_trigger_ht_element *trigger_ht_element; enum lttng_notification_channel_status status = LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; @@ -1138,11 +1141,11 @@ int notification_thread_client_subscribe(struct notification_client *client, * at this point so that conditions that are already TRUE result * in a notification being sent out. * - * The client_list's trigger is used without locking the list itself. - * This is correct since the list doesn't own the trigger and the - * object is immutable. + * Note the iteration on all triggers which share an identical + * `condition` than the one to which the client is registering. This is + * done to ensure that the client receives a distinct notification for + * all triggers that have a `notify` action that have this condition. */ - struct lttng_trigger_ht_element *trigger_ht_element; pthread_mutex_lock(&client_list->lock); cds_list_for_each_entry(trigger_ht_element, &client_list->triggers_list, client_list_trigger_node) { @@ -1151,6 +1154,7 @@ int notification_thread_client_subscribe(struct notification_client *client, WARN("[notification-thread] Evaluation of a condition on client subscription failed, aborting."); ret = -1; free(client_list_element); + pthread_mutex_unlock(&client_list->lock); goto end; } } @@ -2278,6 +2282,69 @@ end: return ret; } +static inline void get_trigger_info_for_log(const struct lttng_trigger *trigger, + const char **trigger_name, + uid_t *trigger_owner_uid) +{ + enum lttng_trigger_status trigger_status; + + trigger_status = lttng_trigger_get_name(trigger, trigger_name); + switch (trigger_status) { + case LTTNG_TRIGGER_STATUS_OK: + break; + case LTTNG_TRIGGER_STATUS_UNSET: + *trigger_name = "(unset)"; + break; + default: + abort(); + } + + trigger_status = lttng_trigger_get_owner_uid(trigger, + trigger_owner_uid); + assert(trigger_status == LTTNG_TRIGGER_STATUS_OK); +} + +static int handle_notification_thread_command_get_trigger( + struct notification_thread_state *state, + const struct lttng_trigger *trigger, + struct lttng_trigger **registered_trigger, + enum lttng_error_code *_cmd_result) +{ + int ret = -1; + struct cds_lfht_iter iter; + struct lttng_trigger_ht_element *trigger_ht_element; + enum lttng_error_code cmd_result = LTTNG_ERR_TRIGGER_NOT_FOUND; + const char *trigger_name; + uid_t trigger_owner_uid; + + rcu_read_lock(); + + cds_lfht_for_each_entry( + state->triggers_ht, &iter, trigger_ht_element, node) { + if (lttng_trigger_is_equal( + trigger, trigger_ht_element->trigger)) { + /* Take one reference on the return trigger. */ + *registered_trigger = trigger_ht_element->trigger; + lttng_trigger_get(*registered_trigger); + ret = 0; + cmd_result = LTTNG_OK; + goto end; + } + } + + /* Not a fatal error if the trigger is not found. */ + get_trigger_info_for_log(trigger, &trigger_name, &trigger_owner_uid); + ERR("Failed to retrieve registered version of trigger: trigger name = '%s', trigger owner uid = %d", + trigger_name, (int) trigger_owner_uid); + + ret = 0; + +end: + rcu_read_unlock(); + *_cmd_result = cmd_result; + return ret; +} + static bool condition_is_supported(struct lttng_condition *condition) { @@ -2691,6 +2758,9 @@ int handle_notification_thread_command_register_trigger( goto error_free_ht_element; } + /* From this point consider the trigger registered. */ + lttng_trigger_set_as_registered(trigger); + /* * Some triggers might need a tracer notifier depending on its * condition and actions. @@ -2890,6 +2960,11 @@ error_free_ht_element: } error: if (free_trigger) { + /* + * Other objects might have a reference to the trigger, mark it + * as unregistered. + */ + lttng_trigger_set_as_unregistered(trigger); lttng_trigger_destroy(trigger); } end: @@ -2971,6 +3046,9 @@ int handle_notification_thread_command_unregister_trigger( cmd_reply = LTTNG_OK; } + trigger_ht_element = caa_container_of(triggers_ht_node, + struct lttng_trigger_ht_element, node); + /* Remove trigger from channel_triggers_ht. */ cds_lfht_for_each_entry(state->channel_triggers_ht, &iter, trigger_list, channel_triggers_ht_node) { @@ -2993,9 +3071,6 @@ int handle_notification_thread_command_unregister_trigger( teardown_tracer_notifier(state, trigger); } - trigger_ht_element = caa_container_of(triggers_ht_node, - struct lttng_trigger_ht_element, node); - if (is_trigger_action_notify(trigger)) { /* * Remove and release the client list from @@ -3125,6 +3200,16 @@ int handle_notification_thread_command( cmd->reply_code = LTTNG_OK; ret = 1; goto end; + case NOTIFICATION_COMMAND_TYPE_GET_TRIGGER: + { + struct lttng_trigger *trigger = NULL; + + ret = handle_notification_thread_command_get_trigger(state, + cmd->parameters.get_trigger.trigger, &trigger, + &cmd->reply_code); + cmd->reply.get_trigger.trigger = trigger; + break; + } case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE: { const enum client_transmission_status client_status = @@ -4333,7 +4418,7 @@ int notification_client_list_send_evaluation( } } - if (client->uid != lttng_credentials_get_uid(trigger_creds) && client->gid != lttng_credentials_get_gid(trigger_creds)) { + if (client->uid != lttng_credentials_get_uid(trigger_creds)) { DBG("[notification-thread] Skipping client at it does not have the permission to receive notification for this trigger"); goto skip_client; } @@ -4521,13 +4606,6 @@ int dispatch_one_event_notifier_notification(struct notification_thread_state *s struct notification_trigger_tokens_ht_element, node); - if (!lttng_trigger_should_fire(element->trigger)) { - ret = 0; - goto end_unlock; - } - - lttng_trigger_fire(element->trigger); - trigger_status = lttng_trigger_get_name(element->trigger, &trigger_name); assert(trigger_status == LTTNG_TRIGGER_STATUS_OK); @@ -4839,12 +4917,6 @@ int handle_notification_thread_channel_sample( goto put_list; } - if (!lttng_trigger_should_fire(trigger)) { - goto put_list; - } - - lttng_trigger_fire(trigger); - /* * Ownership of `evaluation` transferred to the action executor * no matter the result.