rust: list: Switch to kernel::sync atomic primitives

Convert uses of `AtomicBool` to `Atomic<bool>`.

Note that the compare_exchange migration simplifies to
`try_cmpxchg()`, since `try_cmpxchg()` provides relaxed ordering on
failure, making the explicit failure ordering unnecessary.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20251230093718.1852322-3-fujita.tomonori@gmail.com

Author: fujita

rust/kernel/list/arc.rs

@@ -6,11 +6,11 @@
 
 use crate::alloc::{AllocError, Flags};
 use crate::prelude::*;
+use crate::sync::atomic::{ordering, Atomic};
 use crate::sync::{Arc, ArcBorrow, UniqueArc};
 use core::marker::PhantomPinned;
 use core::ops::Deref;
 use core::pin::Pin;
-use core::sync::atomic::{AtomicBool, Ordering};
 
 /// Declares that this type has some way to ensure that there is exactly one `ListArc` instance for
 /// this id.
@@ -469,7 +469,7 @@ where
 /// If the boolean is `false`, then there is no [`ListArc`] for this value.
 #[repr(transparent)]
 pub struct AtomicTracker<const ID: u64 = 0> {
-    inner: AtomicBool,
+    inner: Atomic<bool>,
     // This value needs to be pinned to justify the INVARIANT: comment in `AtomicTracker::new`.
     _pin: PhantomPinned,
 }
@@ -480,12 +480,12 @@ impl<const ID: u64> AtomicTracker<ID> {
         // INVARIANT: Pin-init initializers can't be used on an existing `Arc`, so this value will
         // not be constructed in an `Arc` that already has a `ListArc`.
         Self {
-            inner: AtomicBool::new(false),
+            inner: Atomic::new(false),
             _pin: PhantomPinned,
         }
     }
 
-    fn project_inner(self: Pin<&mut Self>) -> &mut AtomicBool {
+    fn project_inner(self: Pin<&mut Self>) -> &mut Atomic<bool> {
         // SAFETY: The `inner` field is not structurally pinned, so we may obtain a mutable
         // reference to it even if we only have a pinned reference to `self`.
         unsafe { &mut Pin::into_inner_unchecked(self).inner }
@@ -500,7 +500,7 @@ impl<const ID: u64> ListArcSafe<ID> for AtomicTracker<ID> {
 
     unsafe fn on_drop_list_arc(&self) {
         // INVARIANT: We just dropped a ListArc, so the boolean should be false.
-        self.inner.store(false, Ordering::Release);
+        self.inner.store(false, ordering::Release);
     }
 }
 
@@ -514,8 +514,6 @@ unsafe impl<const ID: u64> TryNewListArc<ID> for AtomicTracker<ID> {
     fn try_new_list_arc(&self) -> bool {
         // INVARIANT: If this method returns true, then the boolean used to be false, and is no
         // longer false, so it is okay for the caller to create a new [`ListArc`].
-        self.inner
-            .compare_exchange(false, true, Ordering::Acquire, Ordering::Relaxed)
-            .is_ok()
+        self.inner.cmpxchg(false, true, ordering::Acquire).is_ok()
     }
 }