2023-11-25 12:52:44

by Benno Lossin

Subject: [PATCH 3/3] rust: workqueue: add `#[pin_data]` to `Work`

The previous two patches made it possible to add `#[pin_data]` to
structs with default values to const generic paramters.
This patch makes `Work` use `#[pin_data]` and removes an invocation of
`pin_init_from_closure`. This function is intended as a low level manual
escape hatch, so it is better to rely on the `pin_init!` macro.

Signed-off-by: Benno Lossin <[email protected]>
---

@Miguel: This patch is based on v6.7-rc2, because `workqueue.rs` has yet
to land in rust-next. The first two patches also apply to
rust-next.

rust/kernel/workqueue.rs | 33 ++++++++++++++++++---------------
1 file changed, 18 insertions(+), 15 deletions(-)

diff --git a/rust/kernel/workqueue.rs b/rust/kernel/workqueue.rs
index b67fb1ba168e..15bcfdb1ed33 100644
--- a/rust/kernel/workqueue.rs
+++ b/rust/kernel/workqueue.rs
@@ -334,8 +334,10 @@ pub trait WorkItem<const ID: u64 = 0> {
/// Wraps the kernel's C `struct work_struct`.
///
/// This is a helper type used to associate a `work_struct` with the [`WorkItem`] that uses it.
+#[pin_data]
#[repr(transparent)]
pub struct Work<T: ?Sized, const ID: u64 = 0> {
+ #[pin]
work: Opaque<bindings::work_struct>,
_inner: PhantomData<T>,
}
@@ -357,21 +359,22 @@ pub fn new(name: &'static CStr, key: &'static LockClassKey) -> impl PinInit<Self
where
T: WorkItem<ID>,
{
- // SAFETY: The `WorkItemPointer` implementation promises that `run` can be used as the work
- // item function.
- unsafe {
- kernel::init::pin_init_from_closure(move |slot| {
- let slot = Self::raw_get(slot);
- bindings::init_work_with_key(
- slot,
- Some(T::Pointer::run),
- false,
- name.as_char_ptr(),
- key.as_ptr(),
- );
- Ok(())
- })
- }
+ pin_init!(Self {
+ work: Opaque::ffi_init(|slot| {
+ // SAFETY: The `WorkItemPointer` implementation promises that `run` can be used as
+ // the work item function.
+ unsafe {
+ bindings::init_work_with_key(
+ slot,
+ Some(T::Pointer::run),
+ false,
+ name.as_char_ptr(),
+ key.as_ptr(),
+ )
+ }
+ }),
+ _inner: PhantomData,
+ })
}

/// Get a pointer to the inner `work_struct`.
--
2.40.1

2023-11-25 14:36:07

by Alice Ryhl

Subject: Re: [PATCH 3/3] rust: workqueue: add `#[pin_data]` to `Work`

On 11/25/23 13:51, Benno Lossin wrote:
> + pin_init!(Self {
> + work: Opaque::ffi_init(|slot| {

Surely there should be an <- here instead of the : character?

Alice

2023-11-25 14:55:05

by Benno Lossin

Subject: Re: [PATCH 3/3] rust: workqueue: add `#[pin_data]` to `Work`

On 25.11.23 15:35, Alice Ryhl wrote:
> On 11/25/23 13:51, Benno Lossin wrote:
>> + pin_init!(Self {
>> + work: Opaque::ffi_init(|slot| {
>
> Surely there should be an <- here instead of the : character?

You are absolutely correct. I did this so rustfmt would format it nicely. But
forgot to change it back.

--
Cheers,
Benno