This is the air-side self-checking kiosk option located in T4 and TBIT. China Eastern doesn't seem to participate.
In general, these are your options if you have carry on luggage only - online or mobile check in if the airline allows it. Or wait until the boarding gate is assigned, and go to the gate to check in. The VIP lounge may also issue a boarding pass if you are flying premium cabin (airline and alliance policy varies)