Bug 196190 – [Coordinated Graphics][WinCairo] ASSERTION FAILED: state.id == m_nicosia.state.id

• Component: Platform
• Status: RESOLVED FIXED

[Fujii Hironori]

[Coordinated Graphics][WinCairo] ASSERTION FAILED: state.id == m_nicosia.state.id

I'm working on enabling Coordinated Graphics for WinCairo in Bug 186364.
The compositing layout tests are randomly failing the following assertion.

> ASSERTION FAILED: state.id == m_nicosia.state.id

> python ./Tools/Scripts/run-webkit-tests --debug  --wincairo --no-new-test-results compositing

Callstack:

> WTF!WTFCrash(void)+0x10 [C:\webkit\gb\Source\WTF\wtf\Assertions.cpp @ 305]
> WebKit2!WTFCrashWithInfo(void)+0x20 [C:\webkit\gb\WebKitBuild\Debug\DerivedSources\ForwardingHeaders\wtf\Assertions.h @ 560]
> WebKit2!WebKit::CoordinatedGraphicsScene::purgeGLResources::<unnamed-tag>::operator()(struct Nicosia::Scene::State * state = 0x000001f5`c666a870)+0x8d [C:\webkit\gb\Source\WebKit\Shared\CoordinatedGraphics\CoordinatedGraphicsScene.cpp @ 436]
> WebKit2!Nicosia::Scene::accessState<`lambda at ..\..\Source\WebKit\Shared\CoordinatedGraphics\CoordinatedGraphicsScene.cpp:434:13'>(class WebKit::CoordinatedGraphicsScene::purgeGLResources::<unnamed-tag> * functor = 0x000000de`e15ff408)+0x61 [C:\webkit\gb\WebKitBuild\Debug\DerivedSources\ForwardingHeaders\WebCore\NicosiaScene.h @ 67]
> WebKit2!WebKit::CoordinatedGraphicsScene::purgeGLResources(void)+0xc7 [C:\webkit\gb\Source\WebKit\Shared\CoordinatedGraphics\CoordinatedGraphicsScene.cpp @ 433]
> WebKit2!WebKit::ThreadedCompositor::invalidate::<unnamed-tag>::operator()(void)+0x7c [C:\webkit\gb\Source\WebKit\Shared\CoordinatedGraphics\threadedcompositor\ThreadedCompositor.cpp @ 111]
> WebKit2!WTF::Function<void (void)+0x17 [C:\webkit\gb\WebKitBuild\Debug\DerivedSources\ForwardingHeaders\wtf\Function.h @ 102]
> WebKit2!WTF::Function<void (void)+0x91 [C:\webkit\gb\WebKitBuild\Debug\DerivedSources\ForwardingHeaders\wtf\Function.h @ 57]
> WebKit2!WebKit::CompositingRunLoop::performTaskSync::<unnamed-tag>::operator()(void)+0x31 [C:\webkit\gb\Source\WebKit\Shared\CoordinatedGraphics\threadedcompositor\CompositingRunLoop.cpp @ 91]
> WebKit2!WTF::Function<void (void)+0x17 [C:\webkit\gb\WebKitBuild\Debug\DerivedSources\ForwardingHeaders\wtf\Function.h @ 102]
> WTF!WTF::Function<void (void)+0x90 [C:\webkit\gb\Source\WTF\wtf\Function.h @ 57]
> WTF!WTF::RunLoop::performWork(void)+0x126 [C:\webkit\gb\Source\WTF\wtf\RunLoop.cpp @ 107]
> WTF!WTF::RunLoop::wndProc(struct HWND__ * hWnd = 0x00000000`000606fe, unsigned int message = 0x401, unsigned int64 wParam = 0x000001f5`c6597780, int64 lParam = 0n0)+0x75 [C:\webkit\gb\Source\WTF\wtf\win\RunLoopWin.cpp @ 57]
> WTF!WTF::RunLoop::RunLoopWndProc(struct HWND__ * hWnd = 0x00000000`000606fe, unsigned int message = 0x401, unsigned int64 wParam = 0x000001f5`c6597780, int64 lParam = 0n0)+0x59 [C:\webkit\gb\Source\WTF\wtf\win\RunLoopWin.cpp @ 39]
> USER32!UserCallWinProcCheckWow+0x2c1
> USER32!DispatchMessageWorker+0x1c3
> WTF!WTF::RunLoop::run(void)+0x63 [C:\webkit\gb\Source\WTF\wtf\win\RunLoopWin.cpp @ 69]
> WebKit2!WebKit::createRunLoop::<unnamed-tag>::operator()(void)+0x34 [C:\webkit\gb\Source\WebKit\Shared\CoordinatedGraphics\threadedcompositor\CompositingRunLoop.cpp @ 50]
> WebKit2!WTF::Function<void (void)+0x17 [C:\webkit\gb\WebKitBuild\Debug\DerivedSources\ForwardingHeaders\wtf\Function.h @ 102]
> WTF!WTF::Function<void (void)+0x90 [C:\webkit\gb\Source\WTF\wtf\Function.h @ 57]
> WTF!WTF::Thread::entryPoint(struct WTF::Thread::NewThreadContext * newThreadContext = 0x000001f5`c6631a00)+0x1f3 [C:\webkit\gb\Source\WTF\wtf\Threading.cpp @ 149]
> WTF!WTF::wtfThreadEntryPoint(void * data = 0x000001f5`c6631a00)+0x13 [C:\webkit\gb\Source\WTF\wtf\win\ThreadingWin.cpp @ 152]
> ucrtbase!thread_start<unsigned int +0x3e
> KERNEL32!BaseThreadInitThunk+0x14
> ntdll!RtlUserThreadStart+0x21

[Fujii Hironori]

Created attachment 365841 [details]
CrashLog_0134_2019-03-25_10-42-43-882.txt

[Fujii Hironori]

This assertion assumes two scenes are identical in the composting thread in CoordinatedGraphicsScene::purgeGLResources.

However, state.id is incremented in the main thread in CompositingCoordinator::flushPendingLayerChanges.
https://trac.webkit.org/browser/webkit/trunk/Source/WebKit/WebProcess/WebPage/CoordinatedGraphics/CompositingCoordinator.cpp?rev=243163#L157

The reason why GTK port doesn't have this issue is RunLoop::TimerBase::stop in GTK port stop the RunLoop timer synchronously.
If the RunLoop timer is firing, RunLoop::TimerBase::stop blocks until it finishes.
This is the same reason why GTK port doesn't occur Bug 195550.

[Fujii Hironori]

This assertion has been introduced in Bug 188693.

[Fujii Hironori]

Created attachment 365848 [details]
Patch

[Fujii Hironori]

Landed: https://trac.webkit.org/changeset/243475

[Radar WebKit Bug Importer]

<rdar://problem/49238484>