linux/rust/kernel/sync/arc.rs, branch v6.7

Merge tag 'wq-for-6.7-rust-bindings' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

2023-10-31T06:35:48Z

Pull workqueue rust bindings from Tejun Heo: "Add rust bindings to allow rust code to schedule work items on workqueues. While the current bindings don't cover all of the workqueue API, it provides enough for basic usage and can be expanded as needed" * tag 'wq-for-6.7-rust-bindings' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: rust: workqueue: add examples rust: workqueue: add `try_spawn` helper method rust: workqueue: implement `WorkItemPointer` for pointer types rust: workqueue: add helper for defining work_struct fields rust: workqueue: define built-in queues rust: workqueue: add low-level workqueue bindings rust: sync: add `Arc::{from_raw, into_raw}`

rust: arc: add explicit `drop()` around `Box::from_raw()`

2023-10-05T11:29:50Z

`Box::from_raw()` is `#[must_use]`, which means the result cannot go unused. In Rust 1.71.0, this was not detected because the block expression swallows the diagnostic [1]: unsafe { Box::from_raw(self.ptr.as_ptr()) }; It would have been detected, however, if the line had been instead: unsafe { Box::from_raw(self.ptr.as_ptr()); } i.e. the semicolon being inside the `unsafe` block, rather than outside. In Rust 1.72.0, the compiler started warning about this [2], so without this patch we will get: error: unused return value of `alloc::boxed::Box::::from_raw` that must be used --> rust/kernel/sync/arc.rs:302:22 | 302 | unsafe { Box::from_raw(self.ptr.as_ptr()) }; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = note: call `drop(Box::from_raw(ptr))` if you intend to drop the `Box` = note: `-D unused-must-use` implied by `-D warnings` help: use `let _ = ...` to ignore the resulting value | 302 | unsafe { let _ = Box::from_raw(self.ptr.as_ptr()); }; | +++++++ + Thus add an add an explicit `drop()` as the `#[must_use]`'s annotation suggests (instead of the more general help line). Link: https://github.com/rust-lang/rust/issues/104253 [1] Link: https://github.com/rust-lang/rust/pull/112529 [2] Reviewed-by: Martin Rodriguez Reboredo Reviewed-by: Gary Guo Reviewed-by: Alice Ryhl Reviewed-by: Andreas Hindborg Reviewed-by: Björn Roy Baron Link: https://lore.kernel.org/r/20230823160244.188033-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda

rust: sync: add `Arc::{from_raw, into_raw}`

2023-09-25T19:46:41Z

These methods can be used to turn an `Arc` into a raw pointer and back, in a way that preserves the metadata for fat pointers. This is done using the unstable ptr_metadata feature [1]. However, it could also be done using the unstable pointer_byte_offsets feature [2], which is likely to have a shorter path to stabilization than ptr_metadata. Link: https://github.com/rust-lang/rust/issues/81513 [1] Link: https://github.com/rust-lang/rust/issues/96283 [2] Signed-off-by: Wedson Almeida Filho Co-developed-by: Alice Ryhl Signed-off-by: Alice Ryhl Reviewed-by: Gary Guo Reviewed-by: Martin Rodriguez Reboredo Reviewed-by: Benno Lossin Reviewed-by: Andreas Hindborg Reviewed-by: Boqun Feng Signed-off-by: Tejun Heo

Merge tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

2023-08-29T01:56:38Z

Pull kunit updates from Shuah Khan: - add support for running Rust documentation tests as KUnit tests - make init, str, sync, types doctests compilable/testable - add support for attributes API which include speed, modules attributes, ability to filter and report attributes - add support for marking tests slow using attributes API - add attributes API documentation - fix a wild-memory-access bug in kunit_filter_suites() and a possible memory leak in kunit_filter_suites() - add support for counting number of test suites in a module, list action to kunit test modules, and test filtering on module tests * tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (25 commits) kunit: fix struct kunit_attr header kunit: replace KUNIT_TRIGGER_STATIC_STUB maro with KUNIT_STATIC_STUB_REDIRECT kunit: Allow kunit test modules to use test filtering kunit: Make 'list' action available to kunit test modules kunit: Report the count of test suites in a module kunit: fix uninitialized variables bug in attributes filtering kunit: fix possible memory leak in kunit_filter_suites() kunit: fix wild-memory-access bug in kunit_filter_suites() kunit: Add documentation of KUnit test attributes kunit: add tests for filtering attributes kunit: time: Mark test as slow using test attributes kunit: memcpy: Mark tests as slow using test attributes kunit: tool: Add command line interface to filter and report attributes kunit: Add ability to filter attributes kunit: Add module attribute kunit: Add speed attribute kunit: Add test attributes API structure MAINTAINERS: add Rust KUnit files to the KUnit entry rust: support running Rust documentation tests as KUnit ones rust: types: make doctests compilable/testable ...

rust: delete `ForeignOwnable::borrow_mut`

2023-08-04T15:10:50Z

We discovered that the current design of `borrow_mut` is problematic. This patch removes it until a better solution can be found. Specifically, the current design gives you access to a `&mut T`, which lets you change where the `ForeignOwnable` points (e.g., with `core::mem::swap`). No upcoming user of this API intended to make that possible, making all of them unsound. Signed-off-by: Alice Ryhl Reviewed-by: Gary Guo Reviewed-by: Benno Lossin Reviewed-by: Martin Rodriguez Reboredo Fixes: 0fc4424d24a2 ("rust: types: introduce `ForeignOwnable`") Link: https://lore.kernel.org/r/20230706094615.3080784-1-aliceryhl@google.com Signed-off-by: Miguel Ojeda

rust: sync: make doctests compilable/testable

2023-07-19T15:32:41Z

Rust documentation tests are going to be build/run-tested with the KUnit integration added in a future patch, thus update them to make them compilable/testable so that we may start enforcing it. Reviewed-by: Martin Rodriguez Reboredo Reviewed-by: Björn Roy Baron Reviewed-by: Alice Ryhl Reviewed-by: David Gow Signed-off-by: Miguel Ojeda Signed-off-by: Shuah Khan

rust: sync: reword the `Arc` safety comment for `Sync`

2023-05-31T16:53:10Z

The safety comment on `impl Sync for Arc` references the Send safety comment. This commit avoids that in case the two comments drift apart in the future. Suggested-by: Andreas Hindborg Signed-off-by: Alice Ryhl Reviewed-by: Andreas Hindborg Reviewed-by: Boqun Feng Reviewed-by: Martin Rodriguez Reboredo Reviewed-by: Benno Lossin Link: https://lore.kernel.org/r/20230531145939.3714886-3-aliceryhl@google.com Signed-off-by: Miguel Ojeda

rust: sync: reword the `Arc` safety comment for `Send`

2023-05-31T16:53:10Z

The safety comment on `impl Send for Arc` talks about "directly" accessing the value, when it really means "accessing the value with a mutable reference". This commit clarifies that. Suggested-by: Boqun Feng Signed-off-by: Alice Ryhl Reviewed-by: Andreas Hindborg Reviewed-by: Boqun Feng Reviewed-by: Gary Guo Reviewed-by: Martin Rodriguez Reboredo Reviewed-by: Benno Lossin Link: https://lore.kernel.org/r/20230531145939.3714886-2-aliceryhl@google.com Signed-off-by: Miguel Ojeda

rust: sync: implement `AsRef` for `Arc`

2023-05-31T16:53:10Z

This trait lets you use `Arc` in code that is generic over smart pointer types. The `AsRef` trait should be implemented on all smart pointers. The standard library also implements it on the ordinary `Arc`. Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Signed-off-by: Alice Ryhl Reviewed-by: Martin Rodriguez Reboredo Reviewed-by: Benno Lossin Reviewed-by: Gary Guo Reviewed-by: Andreas Hindborg Link: https://lore.kernel.org/r/20230517200814.3157916-2-aliceryhl@google.com Signed-off-by: Miguel Ojeda

rust: sync: add `Arc::ptr_eq`

2023-05-31T16:53:10Z

Add a method for comparing whether two `Arc` pointers reference the same underlying object. This comparison can already be done by getting a reference to the inner values and comparing whether the references have the same address. However, writing `Arc::ptr_eq(a, b)` is generally less error-prone than doing the same check on the references, since you might otherwise accidentally compare the two `&Arc` references instead, which wont work because those are pointers to pointers to the inner value, when you just want to compare the pointers to the inner value. Also, this method might optimize better because getting a reference to the inner value involves offsetting the pointer, which this method does not need to do. Co-developed-by: Wedson Almeida Filho Signed-off-by: Wedson Almeida Filho Signed-off-by: Alice Ryhl Reviewed-by: Benno Lossin Reviewed-by: Gary Guo Reviewed-by: Martin Rodriguez Reboredo Reviewed-by: Andreas Hindborg Link: https://lore.kernel.org/r/20230517200814.3157916-1-aliceryhl@google.com Signed-off-by: Miguel Ojeda