Introduce a MainThreadBridge class inside WebLockManager

• Component: WebCore Misc.
• Status: RESOLVED FIXED

[Chris Dumez]

Extract all the logic to hop to and back from the main thread out of the WebLockManager and into a MainThreadBridge internal class. This is similar to what was done for BroadcastChannel already.
It provides better structuring and slightly better performance by calling isolatedCopy() on the ClientOrigin only once instead of on every call.

[Chris Dumez]

Created attachment 445786 [details]
Patch

[Darin Adler]

Comment on attachment 445786 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=445786&action=review

> Source/WebCore/Modules/web-locks/WebLockManager.cpp:68
> +class WebLockManager::MainThreadBridge : public ThreadSafeRefCounted<MainThreadBridge, WTF::DestructionThread::Main> {

Are we reference counting this just for the "destroy on main thread" bit? Because if so, I suggest we instead use unique_ptr and null it out on the main thread in ~WebLockManager. I don’t see any ref/deref of this going on.

[Chris Dumez]

Comment on attachment 445786 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=445786&action=review

We need ref-counting to keep ourselves alive while dispatching to the main thread as well.

> Source/WebCore/Modules/web-locks/WebLockManager.cpp:161
> +            Ref protectedThis { *this };

We Ref here.

> Source/WebCore/Modules/web-locks/WebLockManager.cpp:165
> +        downcast<WorkerGlobalScope>(*m_context).thread().workerLoaderProxy().postTaskToLoader([task = WTFMove(task), protectedThis = Ref { *this }](auto& context) {

and here.

[EWS]

Committed r286474 (244813@main): <https://commits.webkit.org/244813@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 445786 [details].

[Radar WebKit Bug Importer]

<rdar://problem/85999405>