error: could not install smartsocket listener: Address already in use

I like to flash my smartphone. There are two tools we should use when flashing: adb and fastboot. But I met a problem:
I want to run new adb server, but it keep showing this message:
error: could not install *smartsocket* listener: Address already in use
and I gave a command ps aux | grep adb, then I got: Readmore