Trait crossbeam_utils::atomic::consume::AtomicConsume

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pub trait AtomicConsume {
    type Val;

    // Required method
    fn load_consume(&self) -> Self::Val;
}
Expand description

Trait which allows reading from primitive atomic types with “consume” ordering.

Required Associated Types§

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type Val

Type returned by load_consume.

Required Methods§

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fn load_consume(&self) -> Self::Val

Loads a value from the atomic using a “consume” memory ordering.

This is similar to the “acquire” ordering, except that an ordering is only guaranteed with operations that “depend on” the result of the load. However consume loads are usually much faster than acquire loads on architectures with a weak memory model since they don’t require memory fence instructions.

The exact definition of “depend on” is a bit vague, but it works as you would expect in practice since a lot of software, especially the Linux kernel, rely on this behavior.

This is currently only implemented on ARM and AArch64, where a fence can be avoided. On other architectures this will fall back to a simple load(Ordering::Acquire).

Implementations on Foreign Types§

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impl<T> AtomicConsume for AtomicPtr<T>

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type Val = *mut T

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fn load_consume(&self) -> Self::Val

Implementors§