Switch wtf/SpinLock to std::atomic

third_party/WebKit/Source/web/tests/SpinLockTest.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 26 matching lines @@
 #include "public/platform/WebThread.h"
 #include "public/platform/WebTraceLocation.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 
 namespace blink {
 
 static const size_t bufferSize = 16;
 
-static int lock = 0;
+static SpinLock lock;
 
 static void fillBuffer(volatile char* buffer, char fillPattern)
 {
     for (size_t i = 0; i < bufferSize; ++i)
         buffer[i] = fillPattern;
 }
 
 static void changeAndCheckBuffer(volatile char* buffer)
 {
     fillBuffer(buffer, '\0');
     int total = 0;
     for (size_t i = 0; i < bufferSize; ++i)
         total += buffer[i];
 
     EXPECT_EQ(0, total);
 
     // This will mess with the other thread's calculation if we accidentally get
     // concurrency.
     fillBuffer(buffer, '!');
 }
 
 static void threadMain(volatile char* buffer)
 {
     for (int i = 0; i < 500000; ++i) {
-        spinLockLock(&lock);
+        SpinLock::Guard guard(lock);
         changeAndCheckBuffer(buffer);
-        spinLockUnlock(&lock);
     }
 }
 
 TEST(SpinLockTest, Torture)
 {
     char sharedBuffer[bufferSize];
 
     OwnPtr<WebThread> thread1 = adoptPtr(Platform::current()->createThread("thread1"));
     OwnPtr<WebThread> thread2 = adoptPtr(Platform::current()->createThread("thread2"));
 
     thread1->taskRunner()->postTask(BLINK_FROM_HERE, new Task(threadSafeBind(&threadMain, AllowCrossThreadAccess(static_cast<char*>(sharedBuffer)))));
     thread2->taskRunner()->postTask(BLINK_FROM_HERE, new Task(threadSafeBind(&threadMain, AllowCrossThreadAccess(static_cast<char*>(sharedBuffer)))));
 
     thread1.clear();
     thread2.clear();
 }
 
 } // namespace blink