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[flip111]

#160

[rust-highfive]

r? @thejpster

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[adamgreig]

My preference is to not change this, but if we do I'd rather reword it to flow better. Something like:

This solves our immediate problem, but we're still left writing a lot of unsafe code which we need to carefully reason about, and we might be using critical sections needlessly. Since each critical section temporarily pauses interrupt processing, there is an associated cost of some extra code size and higher interrupt latency and jitter (interrupts may take longer to be processed, and the time until they are processed will be more variable). Whether this is a problem depends on your system, but in general we'd like to avoid it.