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0 pointsacqq5y ago0 comments

Thanks!

> You still need the mutexes because multiple threads are writing to the same variables at the same time

I understand that for the "data" for which the push exists. Do we however need it for res_mutex when the value that we want to update is a single (I guess integer) variable for which atomic add could be performed? Is there something like atomic add?

0 comments

steveklabnik5y ago

Oh, duh, yes. one line added, two lines changed, I've left them at their indent levels and left the variable name the same:

    use std::sync::atomic::{AtomicU32, Ordering};
    
        let res_mutex = AtomicU32::new(0);

                    res_mutex.fetch_add(result, Ordering::SeqCst);

j / k navigate · click thread line to collapse

0 comments

steveklabnik5y ago

Oh, duh, yes. one line added, two lines changed, I've left them at their indent levels and left the variable name the same:

    use std::sync::atomic::{AtomicU32, Ordering};
    
        let res_mutex = AtomicU32::new(0);

                    res_mutex.fetch_add(result, Ordering::SeqCst);

j / k navigate · click thread line to collapse