diff options
Diffstat (limited to 'rust/kernel')
| -rw-r--r-- | rust/kernel/sync/atomic/internal.rs | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/rust/kernel/sync/atomic/internal.rs b/rust/kernel/sync/atomic/internal.rs index 0dac58bca2b3..ef516bcb02ee 100644 --- a/rust/kernel/sync/atomic/internal.rs +++ b/rust/kernel/sync/atomic/internal.rs @@ -37,16 +37,23 @@ 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)] +// The current helpers of load/store of atomic `i8` and `i16` use `{WRITE,READ}_ONCE()` hence the +// atomicity is only guaranteed against read-modify-write operations if the architecture supports +// native atomic RmW. +// +// In the future when a CONFIG_ARCH_SUPPORTS_ATOMIC_RMW=n architecture plans to support Rust, the +// load/store helpers that guarantee atomicity against RmW operations (usually via a lock) need to +// be added. +crate::static_assert!( + cfg!(CONFIG_ARCH_SUPPORTS_ATOMIC_RMW), + "The current implementation of atomic i8/i16/ptr relies on the architecure being \ + 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; } |