How to implement HashMap-insertable Mutex

hash_mutex.rs

use std::cmp::{PartialEq, Eq};
use std::collections::HashMap;
use std::hash::{Hash, Hasher};
use std::sync::{Arc, Mutex};

#[derive(Debug, Hash)]
struct Hoge {
    a: u32,
    b: u32,
}

#[derive(Debug)]
struct MutHoge(Mutex<Hoge>);

impl Hash for MutHoge {
    fn hash<H: Hasher>(&self, state: &mut H) {
        self.0.lock().unwrap().hash(state)
    }
}

impl PartialEq for MutHoge {
    fn eq(&self, other: &Self) -> bool {
        let s = self.0.lock().unwrap();
        let o = other.0.lock().unwrap();
        s.a == o.a && s.b == o.b
    }
}
impl Eq for MutHoge {}

fn main() {
    let h1 = Arc::new(MutHoge(Mutex::new(Hoge {a:1,b:2})));
    let mut map = HashMap::new();
    map.insert(h1.clone(), "hoge");
    map.insert(h1, "hoge");
    println!("{:?}", map);
}