Challenges of Implementing Linux Kernel's READ_ONCE() and WRITE_ONCE() Macros in Rust
By
todsacerdoti
Toasted golden, schmeared with insight. Top of the rack.
Summary
The article discusses the challenges of implementing READ_ONCE() and WRITE_ONCE() macros from the Linux kernel in Rust code. These macros are essential for lockless algorithms and device-memory access in the kernel, with nearly 8,000 call sites for READ_ONCE(). The article explores why these C-language macros don't translate directly to Rust, examining technical limitations, language differences, and potential workarounds for Rust's integration into the Linux kernel.
Key quotes
· 3 pulledThe READ_ONCE() and WRITE_ONCE() macros are heavily used within the kernel; there are nearly 8,000 call sites for READ_ONCE().
They are key to the implementation of many lockless algorithms and can be necessary for some types of device-memory access.
So one might think that, as the amount of Rust code in the kernel increases, there would be a need for Rust equivalents of these macros.
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