pub(crate) fn probe_handoff_hop_ns() -> Option<HandoffProbe>Expand description
Measure one wake + block + switch hop on THIS host: two threads ping-pong
through a condvar, the blocking handoff cake_handoff_max_ns is a proxy
for. Runs before attach, so it measures the stock kernel path; ~2200 round
trips. Returns ns per one-way hop, or None, and callers keep the defaults.