144 Hour Question Cruise from Shanghai

We are flying from San Diego to Shanghai. There will probably be 1-2 stops on each flight before we reach Shanghai.

We will then spend 2-3 nights in Shanghai, followed by an 8 night cruise to Japan. Once the cruise is over, we will head to the airport and return to San Diego. Prior to reaching San Diego, there will once again be 1-2 stops (possibly Hong Kong, Los Angeles, etc).

Do we need a Chinese Visa, or can we avoid that due to the 144 hour rule?