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:
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;
* 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) {
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;
}
}
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)
{
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.
}
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:
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) {
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
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 =
}
}
- 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;
}
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);
element->trigger),
struct lttng_condition_on_event,
parent),
- trigger_name,
notification->capture_buffer,
notification->capture_buf_size, false);
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.
projects / lttng-tools.git / blobdiff