Locking [LWN.net]

Locking

Posted Sep 24, 2024 20:02 UTC (Tue) by daroc (editor, #160859)
In reply to: Locking by Cyberax
Parent article: Resources for learning Rust for kernel development

One also can drop the guard explicitly:

    drop(guard);

So I don't think it's less flexible, really. But, as in every discussion about programming languages, it's not really about what's possible so much as what the language makes easy or hard. I think it's a good point that Rust's locking is less explicit! That's certainly true, and it is a tradeoff. I (personally) think that the guarantees the compiler provides are worth it, but that doesn't mean we shouldn't acknowledge that less explicit locking does have downsides.

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Forcing explicit destructuring

Posted Sep 24, 2024 20:19 UTC (Tue) by farnz (subscriber, #17727) [Link] (1 responses)

There is some thought being put into whether something like undroppable types would be a useful addition to the language. These would allow Rust for Linux to have a scope guard that must be explicitly destroyed (probably via a fn unlock(self) function), and where dropping them without calling that function is a compile-time error.

Forcing explicit destructuring

Posted Sep 24, 2024 20:21 UTC (Tue) by intelfx (subscriber, #130118) [Link]

> There is some thought being put into whether something like undroppable types would be a useful addition to the language

So… true linear types (as discussed right in this comment section)? :-)

Locking

Posted Sep 25, 2024 17:54 UTC (Wed) by NYKevin (subscriber, #129325) [Link]

One can argue that drop(guard) is just a funny way of spelling (the currently nonexistent) guard.unlock().