Bug 224781 – GPUConnectionToWebProcess::CreateRenderingBackend IPC should be asynchronous

• Status: RESOLVED
• Resolution: FIXED
• Component: WebKit2

[Chris Dumez]

GPUConnectionToWebProcess::CreateRenderingBackend IPC should be asynchronous. We had to make it synchronous as a temporary workaround for Bug 224778. We need to find the underlying cause of Bug 224778 and make the IPC async again.

[Chris Dumez]

When running MotionMark's Canvas-Arcs, in the success case, I see RemoteRenderingBackend::didCreateSharedDisplayListHandle() getting called at least 4 times. However, in the failure case, it seems RemoteRenderingBackend::didCreateSharedDisplayListHandle() is only called once.

In both failure and success cases, I see many calls to RemoteRenderingBackend::wakeUpAndApplyDisplayList() and the initialization stage (GPUConnectionToWebProcess::createRenderingBackend & RemoteRenderingBackend::createImageBuffer) looks the same.

[Chris Dumez]

(In reply to Chris Dumez from comment #1)
> When running MotionMark's Canvas-Arcs, in the success case, I see
> RemoteRenderingBackend::didCreateSharedDisplayListHandle() getting called at
> least 4 times. However, in the failure case, it seems
> RemoteRenderingBackend::didCreateSharedDisplayListHandle() is only called
> once.
> 
> In both failure and success cases, I see many calls to
> RemoteRenderingBackend::wakeUpAndApplyDisplayList() and the initialization
> stage (GPUConnectionToWebProcess::createRenderingBackend &
> RemoteRenderingBackend::createImageBuffer) looks the same.

Note that I haven't been able to reproduce on macOS. On iOS with iPad, it is flaky but fairly easily reproducible.

[Chris Dumez]

<https://commits.webkit.org/236786@main>

[Ling Ho]

rdar://76898311