inprocess: Don't wrap OsIpcReceiver to make it Sync
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Wrap the inprocess receiver in a simple `RefCell<>` instead of `Arc<Mutex<>>` (again). Adding the mutex here is not a good idea: it only adds overhead and potential errors, since not all of the other backends have a `Sync` receiver either; nor does the `mpsc` mechanism `ipc-channel` is modelled after. In fact it fundamentally violates the "single receiver" aspect of `mpsc`, as outlined in servo#89 (comment) Users can still wrap it explicitly if they need to, and know it doesn't introduce incorrect behaviour in the specific use case. This change mostly reverts the `Receiver` part of 30b2024 ; it doesn't re-introduce the explicit `Sync` declaration for `Receiver` though, as that was/is clearly not true without the Mutex -- nor really desirable, as explained above. This change also doesn't touch the `Sender` part, which is a different story.
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@bors-servo: r+ |
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📌 Commit 77469c2 has been approved by |
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inprocess: Don't wrap `OsIpcReceiver` to make it `Sync` Wrap the inprocess receiver in a simple `RefCell<>` instead of `Arc<Mutex<>>` (again). Adding the mutex here is not a good idea: it only adds overhead and potential errors, since not all of the other backends have a `Sync` receiver either; nor does the `mpsc` mechanism `ipc-channel` is modelled after. In fact it fundamentally violates the "single receiver" aspect of `mpsc`, as outlined in #89 (comment) Users can still wrap it explicitly if they need to, and know it doesn't introduce incorrect behaviour in the specific use case. This change mostly reverts the `Receiver` part of 30b2024 ; it doesn't re-introduce the explicit `Sync` declaration for `Receiver` though, as that was/is clearly not true without the Mutex -- nor really desirable, as explained above. This change also doesn't touch the `Sender` part, which is a different story.
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☀️ Test successful - status-appveyor, status-travis |
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Wrap the inprocess receiver in a simple
RefCell<>instead ofArc<Mutex<>>(again).Adding the mutex here is not a good idea: it only adds overhead and
potential errors, since not all of the other backends have a
Syncreceiver either; nor does the
mpscmechanismipc-channelis modelledafter. In fact it fundamentally violates the "single receiver" aspect of
mpsc, as outlined in#89 (comment)
Users can still wrap it explicitly if they need to, and know it doesn't
introduce incorrect behaviour in the specific use case.
This change mostly reverts the
Receiverpart of30b2024 ; it doesn't re-introduce the
explicit
Syncdeclaration forReceiverthough, as that was/isclearly not true without the Mutex -- nor really desirable, as explained
above. This change also doesn't touch the
Senderpart, which is adifferent story.