cruise ship along East Asia, disembarks in Shanghai, then flies out on same day. China Visa needed?

Hi I'm a Canadian passport holder who will be taking a two-week cruise departing from Hong Kong. The cruise will stop at various ports including Singapore, Japan and disembark in Shanghai. There won't be any sightseeing in Shanghai since we will be flying straight out from Shanghai Airport on the same day back to Hong Kong. May I ask if we are eligible for visa-free transit? Many thanks.