Rust: What is the difference between std::sync and tokio::sync?

std::sync — blocking synchronization. tokio::sync — async synchronization.

std::sync:

• Blocking.
• Mutex, RwLock, Arc.
• For sync code.

tokio::sync:

• Async.
• Mutex, RwLock, channels.
• For async code.

1// std::sync
2use std::sync::Mutex;
3let m = Mutex::new(5);
4let val = m.lock().unwrap();
5
6// tokio::sync
7use tokio::sync::Mutex;
8let m = Mutex::new(5);
9let val = m.lock().await;

Key: std for blocking, tokio for async.