Bug 209024 – [ Mac wk2 Debug ] webgpu/whlsl/vector-compare.html is flaky crashing.

• Component: WebGPU
• Status: RESOLVED FIXED

[Jason Lawrence]

Created attachment 393426 [details]
vector-compare-crash-log

webgpu/whlsl/vector-compare.html

Description:
This test is flaky crashing on Mac wk2 Debug. The flaky crashing is present through nearly all of the visible history.

History:
https://results.webkit.org/?suite=layout-tests&test=webgpu%2Fwhlsl%2Fvector-compare.html&recent=false&style=debug&limit=50000

Crash log attached:
Thread 0 Crashed:: Dispatch queue: com.apple.main-thread
0   com.apple.JavaScriptCore      	0x00000002f1e1341e WTFCrash + 14 (Assertions.cpp:305)
1   com.apple.WebCore             	0x00000002d517347b WTFCrashWithInfo(int, char const*, char const*, int) + 27
2   com.apple.WebCore             	0x00000002d51867a8 WTF::RefCountedBase::hasOneRef() const + 104 (RefCounted.h:55)
3   com.apple.WebCore             	0x00000002d69d56af WebCore::GPUBindGroupAllocator::tryReset() + 31 (GPUBindGroupAllocatorMetal.mm:156)
4   com.apple.WebCore             	0x00000002d69d865b WebCore::GPUBindGroup::~GPUBindGroup() + 75 (GPUBindGroupMetal.mm:244)
5   com.apple.WebCore             	0x00000002d69d87f5 WebCore::GPUBindGroup::~GPUBindGroup() + 21 (GPUBindGroupMetal.mm:245)
6   com.apple.WebCore             	0x00000002d660003b std::__1::default_delete<WebCore::GPUBindGroup>::operator()(WebCore::GPUBindGroup*) const + 43 (memory:2339)
7   com.apple.WebCore             	0x00000002d65ffffc WTF::RefCounted<WebCore::GPUBindGroup, std::__1::default_delete<WebCore::GPUBindGroup> >::deref() const + 60 (RefCounted.h:191)
8   com.apple.WebCore             	0x00000002d65fff81 void WTF::derefIfNotNull<WebCore::GPUBindGroup>(WebCore::GPUBindGroup*) + 49 (RefPtr.h:45)
9   com.apple.WebCore             	0x00000002d65fff49 WTF::RefPtr<WebCore::GPUBindGroup, WTF::DumbPtrTraits<WebCore::GPUBindGroup> >::~RefPtr() + 41 (RefPtr.h:70)
10  com.apple.WebCore             	0x00000002d65ffef5 WTF::RefPtr<WebCore::GPUBindGroup, WTF::DumbPtrTraits<WebCore::GPUBindGroup> >::~RefPtr() + 21 (RefPtr.h:70)
11  com.apple.WebCore             	0x00000002d65ffec3 WebCore::WebGPUBindGroup::~WebGPUBindGroup() + 35 (WebGPUBindGroup.h:36)
12  com.apple.WebCore             	0x00000002d65ffe75 WebCore::WebGPUBindGroup::~WebGPUBindGroup() + 21 (WebGPUBindGroup.h:36)

[Jason Lawrence]

I have marked this test as crashing while this issue is investigated here: https://trac.webkit.org/changeset/258368/webkit

This issue is also being tracked here: <rdar://problem/57304995>

[Alexey Proskuryakov]

That's a different issue according to the call stack. Importing as a new one.

[Radar WebKit Bug Importer]

<rdar://problem/60392533>

[Justin Fan]

Created attachment 393568 [details]
Patch

[Darin Adler]

Comment on attachment 393568 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=393568&action=review

> Source/WebCore/platform/graphics/gpu/cocoa/GPUBindGroupAllocatorMetal.mm:160
> +    // This method is called in ~GPUBindGroup(). A refCount of 2 means either only the GPUDevice and the
> +    // lone remaining GPUBindGroup reference this allocator, in which case a reset can occur,
> +    // or the GPUDevice has already been cleaned up and the 2 remaining GPUBindGroups cannot be used again anyway.
> +    if (refCount() != 2)
>          return;

This seems super-fragile.

If you change this 2 to a 1 does a test fail? Which test?

If you change this 2 to a 3 does a test fail? Which test?

[Justin Fan]

Created attachment 394326 [details]
Patch

[Myles C. Maxfield]

Comment on attachment 394326 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=394326&action=review

> Source/WebCore/platform/graphics/gpu/cocoa/GPUBindGroupMetal.mm:242
> +    m_allocator->tryReset();

Can't you do this with a weak pointer instead?

[Justin Fan]

Created attachment 394339 [details]
Patch for landing

[EWS]

Committed r258899: <https://trac.webkit.org/changeset/258899>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 394339 [details].