On Sun, Sep 15, 2024 at 5:36 PM Gary Guo gary@garyguo.net wrote:
On Sun, 15 Sep 2024 14:41:28 +0000 Alice Ryhl aliceryhl@google.com wrote:
The `LockedBy::access` method only requires a shared reference to the owner, so if we have shared access to the `LockedBy` from several threads at once, then two threads could call `access` in parallel and both obtain a shared reference to the inner value. Thus, require that `T: Sync` when calling the `access` method.
An alternative is to require `T: Sync` in the `impl Sync for LockedBy`. This patch does not choose that approach as it gives up the ability to use `LockedBy` with `!Sync` types, which is okay as long as you only use `access_mut`.
Cc: stable@vger.kernel.org Fixes: 7b1f55e3a984 ("rust: sync: introduce `LockedBy`") Signed-off-by: Alice Ryhl aliceryhl@google.com
Reviewed-by: Gary Guo gary@garyguo.net
You probably also want to have a Suggested-by to credit Boqun for suggesting the current implementation.
That's fine. Miguel can add that when he picks this.
Alice