The `unreachable_pub` lint makes us aware of uses of `pub` that are not actually reachable from the crate root. This is considered good because it means reading a `pub` somewhere means it is actually public API. Some of our crates are quite large and keeping their entire API surface in your head is difficult.
We should strive for most items being `pub(crate)`. This lint helps us enforce that.
Pull-Request: #3735.
Implementation of the libp2p perf protocol according to https://github.com/libp2p/specs/pull/478/.
//CC @MarcoPolo as the author of the specification.
**Don't (yet) expect this to produce reliable performance metrics.**
Pull-Request: #3508.