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Hewlett-Packard Firmware Engineer Interview Question

I interviewed in Houston, TX and was asked:
"If you have two devices that can interrupt your program and you want to give priority and atomicity to one of the processes over the other, but you cannot use a semaphore or mutex, how would you do it?"
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Use an interrupt mask.
- Interview Candidate on May 24, 2012 Flag Response
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How would an interrupt mask help? What if the threads are dependent on each other? What if they use the same resource?
- Viewer on Dec 10, 2012 Flag Response
of 1
The answer is that the process who needs to be atomic and is more-important will disable interrupts. The remaining process is therefore prevented from operation until the primary process completes its task, then it re-enables interrupts just after the atomic section.
- OP on Dec 12, 2012 Flag Response

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