diff options
| author | Boqun Feng <boqun.feng@gmail.com> | 2026-03-03 12:16:49 -0800 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2026-03-08 11:06:47 +0100 |
| commit | 4a5dc632e0b603ec1cbbf87b78de86b4b6359cff (patch) | |
| tree | 27ac97b55f2b1d9f27be3b3e9543b5897cfd3974 /rust/kernel/sync | |
| parent | 0da9ca4c08e709144a1bd2f765c14205960ac64d (diff) | |
rust: sync: atomic: Remove bound `T: Sync` for `Atomic::from_ptr()`
Originally, `Atomic::from_ptr()` requires `T` being a `Sync` because I
thought having the ability to do `from_ptr()` meant multiplle
`&Atomic<T>`s shared by different threads, which was identical (or
similar) to multiple `&T`s shared by different threads. Hence `T` was
required to be `Sync`. However this is not true, since `&Atomic<T>` is
not the same at `&T`. Moreover, having this bound makes `Atomic::<*mut
T>::from_ptr()` impossible, which is definitely not intended. Therefore
remove the `T: Sync` bound.
[boqun: Fix title typo spotted by Alice & Gary]
Fixes: 29c32c405e53 ("rust: sync: atomic: Add generic atomics")
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260120115207.55318-2-boqun.feng@gmail.com
Link: https://patch.msgid.link/20260303201701.12204-2-boqun@kernel.org
Diffstat (limited to 'rust/kernel/sync')
| -rw-r--r-- | rust/kernel/sync/atomic.rs | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/rust/kernel/sync/atomic.rs b/rust/kernel/sync/atomic.rs index 4aebeacb961a..296b25e83bbb 100644 --- a/rust/kernel/sync/atomic.rs +++ b/rust/kernel/sync/atomic.rs @@ -204,10 +204,7 @@ impl<T: AtomicType> Atomic<T> { /// // no data race. /// unsafe { Atomic::from_ptr(foo_a_ptr) }.store(2, Release); /// ``` - pub unsafe fn from_ptr<'a>(ptr: *mut T) -> &'a Self - where - T: Sync, - { + pub unsafe fn from_ptr<'a>(ptr: *mut T) -> &'a Self { // CAST: `T` and `Atomic<T>` have the same size, alignment and bit validity. // SAFETY: Per function safety requirement, `ptr` is a valid pointer and the object will // live long enough. It's safe to return a `&Atomic<T>` because function safety requirement |