volatile vs memory barrier for interrupts

Question

Let x and y be variables that are shared between main code and interrupt code.

My idea of volatile is that it is only and alwa

Answer 1

Memory barriers instead of volatile are fine. Linux kernel developers prefer it that way

There are a few things to watch out for.

• Move the barrier after disabling interrupts. Interrupts tend to happen at the worst times.
• You need a second memory barrier before enabling interrupts, for variables that are written in the main program, and read in the interupt handler.
• Disabling interrupts is not enough in a multiprocessor/multicore system, it doesn't prevent another core from running.
• Needless to say, interrupts should not be disabled for extended periods of time, as it can prevent some hardware drivers from functioning.