diff options
| author | FUJITA Tomonori <fujita.tomonori@gmail.com> | 2025-12-28 21:05:46 +0900 |
|---|---|---|
| committer | Boqun Feng <boqun.feng@gmail.com> | 2026-01-09 19:01:41 +0800 |
| commit | 584f286f822afecc1a6521a27b3caf3e2f515d41 (patch) | |
| tree | 895d4b10a785ef15b75826b4651616f2b23f3252 /rust/kernel | |
| parent | 7b001c97d9bdaea50e1e1834040c58f7ef9f4e89 (diff) | |
rust: sync: atomic: Add i8/i16 xchg and cmpxchg support
Add atomic xchg and cmpxchg operation support for i8 and i16 types
with tests.
Note that since the current implementation of
Atomic::<{i8,i16}>::{load,store}() is READ_ONCE()/WRITE_ONCE()-based.
The atomicity between load/store and xchg/cmpxchg is only guaranteed if
the architecture has native RmW support, hence i8/i16 is currently
AtomicImpl only when CONFIG_ARCH_SUPPORTS_ATOMIC_RWM=y.
[boqun: Make i8/i16 AtomicImpl only when
CONFIG_ARCH_SUPPORTS_ATOMIC_RWM=y]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20251228120546.1602275-4-fujita.tomonori@gmail.com
Diffstat (limited to 'rust/kernel')
| -rw-r--r-- | rust/kernel/sync/atomic/internal.rs | 8 | ||||
| -rw-r--r-- | rust/kernel/sync/atomic/predefine.rs | 4 |
2 files changed, 9 insertions, 3 deletions
diff --git a/rust/kernel/sync/atomic/internal.rs b/rust/kernel/sync/atomic/internal.rs index 1b2a7933bc14..0dac58bca2b3 100644 --- a/rust/kernel/sync/atomic/internal.rs +++ b/rust/kernel/sync/atomic/internal.rs @@ -37,10 +37,16 @@ pub trait AtomicImpl: Sized + Send + Copy + private::Sealed { type Delta; } +// The current helpers of load/store uses `{WRITE,READ}_ONCE()` hence the atomicity is only +// guaranteed against read-modify-write operations if the architecture supports native atomic RmW. +#[cfg(CONFIG_ARCH_SUPPORTS_ATOMIC_RMW)] impl AtomicImpl for i8 { type Delta = Self; } +// The current helpers of load/store uses `{WRITE,READ}_ONCE()` hence the atomicity is only +// guaranteed against read-modify-write operations if the architecture supports native atomic RmW. +#[cfg(CONFIG_ARCH_SUPPORTS_ATOMIC_RMW)] impl AtomicImpl for i16 { type Delta = Self; } @@ -274,7 +280,7 @@ declare_and_impl_atomic_methods!( ); declare_and_impl_atomic_methods!( - [ i32 => atomic, i64 => atomic64 ] + [ i8 => atomic_i8, i16 => atomic_i16, i32 => atomic, i64 => atomic64 ] /// Exchange and compare-and-exchange atomic operations pub trait AtomicExchangeOps { /// Atomic exchange. diff --git a/rust/kernel/sync/atomic/predefine.rs b/rust/kernel/sync/atomic/predefine.rs index 51e9df0cf56e..248d26555ccf 100644 --- a/rust/kernel/sync/atomic/predefine.rs +++ b/rust/kernel/sync/atomic/predefine.rs @@ -149,7 +149,7 @@ mod tests { #[test] fn atomic_xchg_tests() { - for_each_type!(42 in [i32, i64, u32, u64, isize, usize] |v| { + for_each_type!(42 in [i8, i16, i32, i64, u32, u64, isize, usize] |v| { let x = Atomic::new(v); let old = v; @@ -162,7 +162,7 @@ mod tests { #[test] fn atomic_cmpxchg_tests() { - for_each_type!(42 in [i32, i64, u32, u64, isize, usize] |v| { + for_each_type!(42 in [i8, i16, i32, i64, u32, u64, isize, usize] |v| { let x = Atomic::new(v); let old = v; |