add: release_lock(&CACHE_LOCK(_c));
context: int cache_update_unsafe(cache_t* _c, db_con_t* _con, c_elem_t** _el, location_t* _loc, int* _sr){	if (update_location(_con, ELEM_LOC((*_el)), _loc, _sr) == FALSE) {		ERR("Error while updating location");		return FALSE;	}	if (!(ELEM_LOC((*_el))->contacts)) {		slot_rem_elem((*_el));		cache_rem_elem(_c, (*_el));		free_element((*_el));		*_el = NULL;	}	free_location(_loc);	return TRUE;}