Unpoison CrossThreadPersistents

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 1121 matching lines @@
     // The default behavior is lazy sweeping.
     scheduleIdleLazySweep();
   }
 }
 
 #if defined(ADDRESS_SANITIZER)
 void ThreadState::poisonAllHeaps() {
   // Poisoning all unmarked objects in the other arenas.
   for (int i = 1; i < BlinkGC::NumberOfArenas; i++)
     m_arenas[i]->poisonArena();
+  ProcessHeap::crossThreadPersistentRegion().unpoisonCrossThreadPersistents();

[haraken, 2016/10/17 07:32:40]

Add a comment about why we do this.

[keishi, 2016/10/17 07:43:00]

Done.

 }
 
 void ThreadState::poisonEagerArena() {
   m_arenas[BlinkGC::EagerSweepArenaIndex]->poisonArena();
+  ProcessHeap::crossThreadPersistentRegion().unpoisonCrossThreadPersistents();
 }
 #endif
 
 void ThreadState::eagerSweep() {
 #if defined(ADDRESS_SANITIZER)
   poisonEagerArena();
 #endif
   ASSERT(checkThread());
   // Some objects need to be finalized promptly and cannot be handled
   // by lazy sweeping. Keep those in a designated heap and sweep it
@@ skipping 656 matching lines @@
     collectGarbage(BlinkGC::NoHeapPointersOnStack, BlinkGC::GCWithSweep,
                    BlinkGC::ForcedGC);
     size_t liveObjects = heap().heapStats().markedObjectSize();
     if (liveObjects == previousLiveObjects)
       break;
     previousLiveObjects = liveObjects;
   }
 }
 
 }  // namespace blink