[tip: locking/core] rust: sync: atomic: Update documentation for `fetch_add()`

[tip-bot2 for Andreas Hindborg]

The following commit has been merged into the locking/core branch of tip:

Commit-ID:     0b864375d93d1509821def9c4b15f845d314a5d2
Gitweb:        https://git.kernel.org/tip/0b864375d93d1509821def9c4b15f845d314a5d2
Author:        Andreas Hindborg <a.hindborg@xxxxxxxxxx>
AuthorDate:    Tue, 03 Mar 2026 12:17:00 -08:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Sun, 08 Mar 2026 11:06:51 +01:00

rust: sync: atomic: Update documentation for `fetch_add()`

The documentation for `fetch_add()` does not indicate that the original
value is returned by `fetch_add()`. Update the documentation so this is
clear.

Signed-off-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>
Signed-off-by: Boqun Feng <boqun@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Alice Ryhl <aliceryhl@xxxxxxxxxx>
Link: https://patch.msgid.link/20260220-atomic-sub-v3-2-e63cbed1d2aa@xxxxxxxxxx
Link: https://patch.msgid.link/20260303201701.12204-13-boqun@xxxxxxxxxx
---
 rust/kernel/sync/atomic.rs | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/rust/kernel/sync/atomic.rs b/rust/kernel/sync/atomic.rs
index 545a8d3..9cd009d 100644
--- a/rust/kernel/sync/atomic.rs
+++ b/rust/kernel/sync/atomic.rs
@@ -545,16 +545,14 @@ where
     /// use kernel::sync::atomic::{Atomic, Acquire, Full, Relaxed};
     ///
     /// let x = Atomic::new(42);
-    ///
     /// assert_eq!(42, x.load(Relaxed));
-    ///
-    /// assert_eq!(54, { x.fetch_add(12, Acquire); x.load(Relaxed) });
+    /// assert_eq!(42, x.fetch_add(12, Acquire));
+    /// assert_eq!(54, x.load(Relaxed));
     ///
     /// let x = Atomic::new(42);
-    ///
     /// assert_eq!(42, x.load(Relaxed));
-    ///
-    /// assert_eq!(54, { x.fetch_add(12, Full); x.load(Relaxed) } );
+    /// assert_eq!(42, x.fetch_add(12, Full));
+    /// assert_eq!(54, x.load(Relaxed));
     /// ```
     #[inline(always)]
     pub fn fetch_add<Rhs, Ordering: ordering::Ordering>(&self, v: Rhs, _: Ordering) -> T