I have the GUI Qthread and n workers Qthreads. I'm looking the way to do a syncronous call to a function that lives and must run on the GUI thread from the workers (with the minimun delay) and blocks the worker thread until is complete (about 20 ms).

With signals I've delays more than a second in process the signal. I try send events, but the call don't run on main thread.

What can be the best way to do this?