Ethernet polling and patch-pulling latency

Naming is hard, but if those are the only two choices then POLL_BUSY_LOOP is better. The other name is too tempting and you'll always be having to explain it and why no one outside the financial industry should use it. By naming it something scary you've cut your support costs dramatically.

Honestly, there will always be people who want to busy loop, so you're right that it's an implementation detail but it's also probably not going to change.