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2025-07-17rust: time: Pass correct timer mode ID to hrtimer_start_range_nsLyude Paul
While rebasing rvkms I noticed that timers I was setting seemed to have pretty random timer values that amounted slightly over 2x the time value I set each time. After a lot of debugging, I finally managed to figure out why: it seems that since we moved to Instant and Delta, we mistakenly began passing the clocksource ID to hrtimer_start_range_ns, when we should be passing the timer mode instead. Presumably, this works fine for simple relative timers - but immediately breaks on other types of timers. So, fix this by passing the ID for the timer mode instead. Signed-off-by: Lyude Paul <lyude@redhat.com> Acked-by: Andreas Hindborg <a.hindborg@kernel.org> Reviewed-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Fixes: e0c0ab04f678 ("rust: time: Make HasHrTimer generic over HrTimerMode") Link: https://lore.kernel.org/r/20250710225129.670051-1-lyude@redhat.com [ Removed cast, applied `rustfmt`, fixed `Fixes:` tag. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-07-16Merge tag 'rust-timekeeping-for-v6.17' of ↵Miguel Ojeda
https://github.com/Rust-for-Linux/linux into rust-next Pull timekeeping updates from Andreas Hindborg: - Make 'Instant' generic over clock source. This allows the compiler to assert that arithmetic expressions involving the 'Instant' use 'Instants' based on the same clock source. - Make 'HrTimer' generic over the timer mode. 'HrTimer' timers take a 'Duration' or an 'Instant' when setting the expiry time, depending on the timer mode. With this change, the compiler can check the type matches the timer mode. - Add an abstraction for 'fsleep'. 'fsleep' is a flexible sleep function that will select an appropriate sleep method depending on the requested sleep time. - Avoid 64-bit divisions on 32-bit hardware when calculating timestamps. - Seal the 'HrTimerMode' trait. This prevents users of the 'HrTimerMode' from implementing the trait on their own types. * tag 'rust-timekeeping-for-v6.17' of https://github.com/Rust-for-Linux/linux: rust: time: Add wrapper for fsleep() function rust: time: Seal the HrTimerMode trait rust: time: Remove Ktime in hrtimer rust: time: Make HasHrTimer generic over HrTimerMode rust: time: Add HrTimerExpires trait rust: time: Replace HrTimerMode enum with trait-based mode types rust: time: Add ktime_get() to ClockSource trait rust: time: Make Instant generic over ClockSource rust: time: Replace ClockId enum with ClockSource trait rust: time: Avoid 64-bit integer division on 32-bit architectures
2025-07-15rust: types: rename Opaque::raw_get to cast_intoAlice Ryhl
In the previous patch we added Opaque::cast_from() that performs the opposite operation to Opaque::raw_get(). For consistency with this naming, rename raw_get() to cast_from(). There are a few other options such as calling cast_from() something closer to raw_get() rather than renaming this method. However, I could not find a great naming scheme that works with raw_get(). The previous version of this patch used from_raw(), but functions of that name typically have a different signature, so that's not a great option. Suggested-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Alice Ryhl <aliceryhl@google.com> Acked-by: Benno Lossin <lossin@kernel.org> Acked-by: Andreas Hindborg <a.hindborg@kernel.org> Acked-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Danilo Krummrich <dakr@kernel.org> Acked-by: Danilo Krummrich <dakr@kernel.org> Link: https://lore.kernel.org/r/20250624-opaque-from-raw-v2-2-e4da40bdc59c@google.com [ Removed `HrTimer::raw_get` change. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-06-30rust: time: Add wrapper for fsleep() functionFUJITA Tomonori
Add a wrapper for fsleep(), flexible sleep functions in include/linux/delay.h which typically deals with hardware delays. The kernel supports several sleep functions to handle various lengths of delay. This adds fsleep(), automatically chooses the best sleep method based on a duration. fsleep() can only be used in a nonatomic context. This requirement is not checked by these abstractions, but it is intended that klint [1] or a similar tool will be used to check it in the future. Link: https://rust-for-linux.com/klint [1] Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Fiona Behrens <me@kloenk.dev> Tested-by: Daniel Almeida <daniel.almeida@collabora.com> Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org> Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Link: https://lore.kernel.org/r/20250617144155.3903431-3-fujita.tomonori@gmail.com Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-06-30rust: time: Seal the HrTimerMode traitFUJITA Tomonori
Prevent downstream crates or drivers from implementing `HrTimerMode` for arbitrary types, which could otherwise leads to unsupported behavior. Introduce a `private::Sealed` trait and implement it for all types that implement `HrTimerMode`. Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Link: https://lore.kernel.org/r/20250617232806.3950141-1-fujita.tomonori@gmail.com Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-06-24rust: time: Remove Ktime in hrtimerFUJITA Tomonori
Remove the use of `Ktime` from the hrtimer code, which was originally introduced as a temporary workaround. The hrtimer has now been fully converted to use the `Instant` and `Delta` types instead. Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org> Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Link: https://lore.kernel.org/r/20250610132823.3457263-6-fujita.tomonori@gmail.com Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-06-24rust: time: Make HasHrTimer generic over HrTimerModeFUJITA Tomonori
Add a `TimerMode` associated type to the `HasHrTimer` trait to represent the operational mode of the timer, such as absolute or relative expiration. This new type must implement the `HrTimerMode` trait, which defines how expiration values are interpreted. Update the `start()` method to accept an `expires` parameter of type `<Self::TimerMode as HrTimerMode>::Expires` instead of the fixed `Ktime`. This enables different timer modes to provide strongly typed expiration values, such as `Instant<C>` or `Delta`. The `impl_has_hr_timer` macro is also extended to allow specifying the `HrTimerMode`. In the following example, it guarantees that the `start()` method for `Foo` only accepts `Instant<Monotonic>`. Using a `Delta` or an `Instant` with a different clock source will result in a compile-time error: struct Foo { #[pin] timer: HrTimer<Self>, } impl_has_hr_timer! { impl HasHrTimer<Self> for Foo { mode : AbsoluteMode<Monotonic>, field : self.timer } } This design eliminates runtime mismatches between expires types and clock sources, and enables stronger type-level guarantees throughout hrtimer. Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org> Link: https://lore.kernel.org/r/20250610132823.3457263-5-fujita.tomonori@gmail.com [ changed conversion method names to `as_*` - Andreas ] Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-06-24rust: time: Add HrTimerExpires traitFUJITA Tomonori
Introduce the `HrTimerExpires` trait to represent types that can be used as expiration values for high-resolution timers. Define a required method, `into_nanos()`, which returns the expiration time as a raw nanosecond value suitable for use with C's hrtimer APIs. Also extend the `HrTimerMode` to use the `HrTimerExpires` trait. This refactoring is a preparation for enabling hrtimer code to work uniformly with both absolute and relative expiration modes. Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org> Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Link: https://lore.kernel.org/r/20250610132823.3457263-4-fujita.tomonori@gmail.com [ changed conversion method names to `as_*` - Andreas ] Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-06-24rust: time: Replace HrTimerMode enum with trait-based mode typesFUJITA Tomonori
Replace the `HrTimerMode` enum with a trait-based approach that uses zero-sized types to represent each mode of operation. Each mode now implements the `HrTimerMode` trait. This refactoring is a preparation for replacing raw `Ktime` in HrTimer with the `Instant` and `Delta` types, and for making `HrTimer` generic over a `ClockSource`. Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org> Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Link: https://lore.kernel.org/r/20250610132823.3457263-3-fujita.tomonori@gmail.com Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-06-22rust: enable `clippy::ptr_as_ptr` lintTamir Duberstein
In Rust 1.51.0, Clippy introduced the `ptr_as_ptr` lint [1]: > Though `as` casts between raw pointers are not terrible, > `pointer::cast` is safer because it cannot accidentally change the > pointer's mutability, nor cast the pointer to other types like `usize`. There are a few classes of changes required: - Modules generated by bindgen are marked `#[allow(clippy::ptr_as_ptr)]`. - Inferred casts (` as _`) are replaced with `.cast()`. - Ascribed casts (` as *... T`) are replaced with `.cast::<T>()`. - Multistep casts from references (` as *const _ as *const T`) are replaced with `core::ptr::from_ref(&x).cast()` with or without `::<T>` according to the previous rules. The `core::ptr::from_ref` call is required because `(x as *const _).cast::<T>()` results in inference failure. - Native literal C strings are replaced with `c_str!().as_char_ptr()`. - `*mut *mut T as _` is replaced with `let *mut *const T = (*mut *mut T)`.cast();` since pointer to pointer can be confusing. Apply these changes and enable the lint -- no functional change intended. Link: https://rust-lang.github.io/rust-clippy/master/index.html#ptr_as_ptr [1] Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Tamir Duberstein <tamird@gmail.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Danilo Krummrich <dakr@kernel.org> Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-1-f43b024581e8@gmail.com [ Added `.cast()` for `opp`. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-06-16rust: time: Replace ClockId enum with ClockSource traitFUJITA Tomonori
Replace the ClockId enum with a trait-based abstraction called ClockSource. This change enables expressing clock sources as types and leveraging the Rust type system to enforce clock correctness at compile time. This also sets the stage for future generic abstractions over Instant types such as Instant<C>. Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Link: https://lore.kernel.org/r/20250610093258.3435874-2-fujita.tomonori@gmail.com Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-06-10rust: time: Fix compile error in impl_has_hr_timer macroFUJITA Tomonori
Fix a compile error in the `impl_has_hr_timer!` macro as follows: error[E0599]: no method named cast_mut found for raw pointer *mut Foo in the current scope The `container_of!` macro already returns a mutable pointer when used in a `*mut T` context so the `.cast_mut()` method is not available. [ We missed this one because there is no caller yet and it is a macro. - Miguel ] Fixes: 74d6a606c2b3 ("rust: retain pointer mut-ness in `container_of!`") Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Reviewed-by: Benno Lossin <lossin@kernel.org> Acked-by: Andreas Hindborg <a.hindborg@kernel.org> Link: https://lore.kernel.org/r/20250606020505.3186533-1-fujita.tomonori@gmail.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-05-22rust: workaround `bindgen` issue with forward references to `enum` typesMiguel Ojeda
`bindgen` currently generates the wrong type for an `enum` when there is a forward reference to it. For instance: enum E; enum E { A }; generates: pub const E_A: E = 0; pub type E = i32; instead of the expected: pub const E_A: E = 0; pub type E = ffi::c_uint; The issue was reported to upstream `bindgen` [1]. Now, both GCC and Clang support silently these forward references to `enum` types, unless `-Wpedantic` is passed, and it turns out that some headers in the kernel depend on them. Thus, depending on how the headers are included, which in turn may depend on the kernel configuration or the architecture, we may get a different type on the Rust side for a given C `enum`. That can be quite confusing, to say the least, especially since developers may only notice issues when building for other architectures like in [2]. In particular, they may end up forcing a cast and adding an `#[allow(clippy::unnecessary_cast)]` like it was done in commit 94e05a66ea3e ("rust: hrtimer: allow timer restart from timer handler"), which isn't great. Instead, let's have a section at the top of our `bindings_helper.h` that `#include`s the headers with the affected types -- hopefully there are not many cases and there is a single ordering that covers all cases. This allows us to remove the cast and the `#[allow]`, thus keeping the correct code in the source files. When the issue gets resolved in upstream `bindgen` (and we update our minimum `bindgen` version), we can easily remove this section at the top. Link: https://github.com/rust-lang/rust-bindgen/issues/3179 [1] Link: https://lore.kernel.org/rust-for-linux/87tt7md1s6.fsf@kernel.org/ [2] Acked-by: Andreas Hindborg <a.hindborg@kernel.org> Link: https://lore.kernel.org/r/20250325184309.97170-1-ojeda@kernel.org [ Added extra paragraph on the comment to clarify that the workaround may not be possible in some cases. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-04-29rust: hrtimer: Add Ktime temporarilyFUJITA Tomonori
Add Ktime temporarily until hrtimer is refactored to use Instant and Delta types. Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Link: https://lore.kernel.org/r/20250423192857.199712-2-fujita.tomonori@gmail.com Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-25Merge tag 'rust-hrtimer-for-v6.15-v3' of ↵Miguel Ojeda
https://github.com/Rust-for-Linux/linux into rust-next Pull rust-hrtimer updates from Andreas Hindborg: "Introduce Rust support for the 'hrtimer' subsystem: - Add a way to use the 'hrtimer' subsystem from Rust. Rust code can now set up intrusive timers without allocating when starting the timer. - Add support for 'Pin<Box<_>>', 'Arc<_>', 'Pin<&_>' and 'Pin<&mut _>' as pointer types for use with timer callbacks. - Add support for setting clock source and timer mode. 'kernel' crate: - Add 'Arc::as_ptr' for converting an 'Arc' to a raw pointer. This is a dependency for the 'hrtimer' API. - Add 'Box::into_pin' for converting a 'Box<_>' into a 'Pin<Box<_>>' to align with Rust 'alloc'. This is a dependency for the 'hrtimer' API." * tag 'rust-hrtimer-for-v6.15-v3' of https://github.com/Rust-for-Linux/linux: rust: hrtimer: add maintainer entry rust: hrtimer: add clocksource selection through `ClockId` rust: hrtimer: add `HrTimerMode` rust: hrtimer: implement `HrTimerPointer` for `Pin<Box<T>>` rust: alloc: add `Box::into_pin` rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>` rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&T>` rust: hrtimer: add `hrtimer::ScopedHrTimerPointer` rust: hrtimer: add `UnsafeHrTimerPointer` rust: hrtimer: allow timer restart from timer handler rust: hrtimer: implement `HrTimerPointer` for `Arc` rust: sync: add `Arc::as_ptr` rust: hrtimer: introduce hrtimer support
2025-03-22rust: hrtimer: add clocksource selection through `ClockId`Andreas Hindborg
Allow selecting a clock source for timers by passing a `ClockId` variant to `HrTimer::new`. Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Lyude Paul <lyude@redhat.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-12-73586e2bd5f1@kernel.org Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-22rust: hrtimer: add `HrTimerMode`Andreas Hindborg
Allow selection of timer mode by passing a `HrTimerMode` variant to `HrTimer::new`. Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Lyude Paul <lyude@redhat.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-11-73586e2bd5f1@kernel.org Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-22rust: hrtimer: implement `HrTimerPointer` for `Pin<Box<T>>`Andreas Hindborg
Allow `Pin<Box<T>>` to be the target of a timer callback. Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Lyude Paul <lyude@redhat.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-10-73586e2bd5f1@kernel.org Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-22rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&mut T>`Andreas Hindborg
Allow pinned mutable references to structs that contain a `HrTimer` node to be scheduled with the `hrtimer` subsystem. Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Lyude Paul <lyude@redhat.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-8-73586e2bd5f1@kernel.org Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-22rust: hrtimer: implement `UnsafeHrTimerPointer` for `Pin<&T>`Andreas Hindborg
Allow pinned references to structs that contain a `HrTimer` node to be scheduled with the `hrtimer` subsystem. Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Lyude Paul <lyude@redhat.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-7-73586e2bd5f1@kernel.org Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-22rust: hrtimer: add `hrtimer::ScopedHrTimerPointer`Andreas Hindborg
Add the trait `ScopedHrTimerPointer` to allow safe use of stack allocated timers. Safety is achieved by pinning the stack in place while timers are running. Implement the trait for all types that implement `UnsafeHrTimerPointer`. Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Lyude Paul <lyude@redhat.com> Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-6-73586e2bd5f1@kernel.org Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-22rust: hrtimer: add `UnsafeHrTimerPointer`Andreas Hindborg
Add a trait to allow unsafely queuing stack allocated timers. Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Lyude Paul <lyude@redhat.com> Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-5-73586e2bd5f1@kernel.org Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-22rust: hrtimer: allow timer restart from timer handlerAndreas Hindborg
Allow timer handlers to report that they want a timer to be restarted after the timer handler has finished executing. Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Tamir Duberstein <tamird@gmail.com> Reviewed-by: Lyude Paul <lyude@redhat.com> Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-4-73586e2bd5f1@kernel.org Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-11rust: hrtimer: implement `HrTimerPointer` for `Arc`Andreas Hindborg
Allow the use of intrusive `hrtimer` fields in structs that are managed by an `Arc` by implementing `HrTimerPointer` and `RawTimerCallbck` for `Arc`. Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Lyude Paul <lyude@redhat.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-3-73586e2bd5f1@kernel.org Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>
2025-03-11rust: hrtimer: introduce hrtimer supportAndreas Hindborg
Add support for intrusive use of the hrtimer system. For now, only add support for embedding one timer per Rust struct. The hrtimer Rust API is based on the intrusive style pattern introduced by the Rust workqueue API. Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Tamir Duberstein <tamird@gmail.com> Reviewed-by: Lyude Paul <lyude@redhat.com> Link: https://lore.kernel.org/r/20250309-hrtimer-v3-v6-12-rc2-v12-1-73586e2bd5f1@kernel.org Signed-off-by: Andreas Hindborg <a.hindborg@kernel.org>