Implement offscreenCanvas.getContext('webgl') on a worker thread

third_party/WebKit/Source/platform/heap/ThreadState.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 208 matching lines @@
     }
     ASSERT(checkThread());
 
     // Finish sweeping.
     completeSweep();
 
     // From here on ignore all conservatively discovered
     // pointers into the heap owned by this thread.
     m_isTerminating = true;
 
+    releaseStaticPersistentNodes();

[xidachen, 2016/05/07 17:07:49]

sof@, haraken@: without this line, the layout test hits the
ASSERT(!currentCount);

[sof, 2016/05/07 17:11:23]

Really, isn't the releaseStaticPersistentNodes() call below sufficient?

[xidachen, 2016/05/07 17:28:30]

I just tried something, without this line here, and change the while loop to be

while(currentCount != oldCount || currentCount)

in that case, we will for sure not hit that ASSERT.

WDYT?

[sof, 2016/05/07 17:33:32]

Not a good idea, as you will be perpetually stuck in the loop if there are
persistents alive that aren't released.

The loop will be executed at least once, so the claim that a test is failing
doesn't make sense to me.

+
     // Set the terminate flag on all heap pages of this thread. This is used to
     // ensure we don't trace pages on other threads that are not part of the
     // thread local GC.
     prepareForThreadStateTermination();
 
     ProcessHeap::crossThreadPersistentRegion().prepareForThreadStateTermination(this);
 
     // Do thread local GC's as long as the count of thread local Persistents
     // changes and is above zero.
     int oldCount = -1;
@@ skipping 1282 matching lines @@
     threadDump->addScalar("dead_count", "objects", totalDeadCount);
     threadDump->addScalar("live_size", "bytes", totalLiveSize);
     threadDump->addScalar("dead_size", "bytes", totalDeadSize);
 
     WebMemoryAllocatorDump* heapsDump = BlinkGCMemoryDumpProvider::instance()->createMemoryAllocatorDumpForCurrentGC(heapsDumpName);
     WebMemoryAllocatorDump* classesDump = BlinkGCMemoryDumpProvider::instance()->createMemoryAllocatorDumpForCurrentGC(classesDumpName);
     BlinkGCMemoryDumpProvider::instance()->currentProcessMemoryDump()->addOwnershipEdge(classesDump->guid(), heapsDump->guid());
 }
 
 } // namespace blink