Revert of Switch wtf/SpinLock to std::atomic

third_party/WebKit/Source/wtf/Partitions.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 21 matching lines @@
 #include "wtf/Partitions.h"
 
 #include "wtf/Alias.h"
 #include "wtf/MainThread.h"
 #include "wtf/PartitionAllocator.h"
 
 namespace WTF {
 
 const char* const Partitions::kAllocatedObjectPoolName = "partition_alloc/allocated_objects";
 
-SpinLock Partitions::s_initializationLock;
+int Partitions::s_initializationLock = 0;
 bool Partitions::s_initialized = false;
 
 PartitionAllocatorGeneric Partitions::m_fastMallocAllocator;
 PartitionAllocatorGeneric Partitions::m_bufferAllocator;
 SizeSpecificPartitionAllocator<3328> Partitions::m_nodeAllocator;
 SizeSpecificPartitionAllocator<1024> Partitions::m_layoutAllocator;
 HistogramEnumerationFunction Partitions::m_histogramEnumeration = nullptr;
 
 void Partitions::initialize(HistogramEnumerationFunction histogramEnumeration)
 {
-    SpinLock::Guard guard(s_initializationLock);
+    spinLockLock(&s_initializationLock);
 
     if (!s_initialized) {
         partitionAllocGlobalInit(&Partitions::handleOutOfMemory);
         m_fastMallocAllocator.init();
         m_bufferAllocator.init();
         m_nodeAllocator.init();
         m_layoutAllocator.init();
         m_histogramEnumeration = histogramEnumeration;
         s_initialized = true;
     }
+
+    spinLockUnlock(&s_initializationLock);
 }
 
 void Partitions::shutdown()
 {
-    SpinLock::Guard guard(s_initializationLock);
+    spinLockLock(&s_initializationLock);
 
     // We could ASSERT here for a memory leak within the partition, but it leads
     // to very hard to diagnose ASSERTs, so it's best to leave leak checking for
     // the valgrind and heapcheck bots, which run without partitions.
     if (s_initialized) {
         (void) m_layoutAllocator.shutdown();
         (void) m_nodeAllocator.shutdown();
         (void) m_bufferAllocator.shutdown();
         (void) m_fastMallocAllocator.shutdown();
     }
+
+    spinLockUnlock(&s_initializationLock);
 }
 
 void Partitions::decommitFreeableMemory()
 {
     RELEASE_ASSERT(isMainThread());
     if (!s_initialized)
         return;
 
     partitionPurgeMemoryGeneric(bufferPartition(), PartitionPurgeDecommitEmptyPages);
     partitionPurgeMemoryGeneric(fastMallocPartition(), PartitionPurgeDecommitEmptyPages);
@@ skipping 116 matching lines @@
     if (totalUsage >= 64 * 1024 * 1024)
         partitionsOutOfMemoryUsing64M();
     if (totalUsage >= 32 * 1024 * 1024)
         partitionsOutOfMemoryUsing32M();
     if (totalUsage >= 16 * 1024 * 1024)
         partitionsOutOfMemoryUsing16M();
     partitionsOutOfMemoryUsingLessThan16M();
 }
 
 } // namespace WTF