I think you missed an important item.
When you read a switch, even if you don't intend to debounce it properly, it's not good practice to simply have the port connect to the switch, which is often off the PCB. This sets you up for electrostatic discharges killing your uC.
Instead, put a resistor in series with the pin going to the resistor. The resistor value doesn't have to be tightly specified as values from 1K to 100K all tend to work fine. The uC port when used as an input is a CMOS input and almost an open circuit anyway, to the resistor will not significantly affect the reading process. It may be a tad slower because of the gate input capacitance and the resistance, but it you're timed that tightly, you're too close to the edge anyway.
Any resistance in that input port pin will give the built in uC input protection diodes a chance to save the uCs life. No resistance may well let it get killed.