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

sync::Mutex — blocking. tokio::sync::Mutex — async.

sync::Mutex:

• Blocking.
• Blocks thread.
• For sync code.

tokio::sync::Mutex:

• Async.
• Non-blocking.
• For async code.

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

Key: std for blocking, tokio for async.