Fix issue 142

src/v8threads.h

 // Copyright 2008 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 69 matching lines @@
  private:
   static void EagerlyArchiveThread();
 
   static Mutex* mutex_;
   static ThreadHandle mutex_owner_;
   static ThreadHandle lazily_archived_thread_;
   static ThreadState* lazily_archived_thread_state_;
 };
 
 
+// The ContextSwitcher thread is used to schedule regular preemptions to
+// multiple running V8 threads. Generally it is needed to call StartPreemption

[Erik Corry, 2008/12/17 14:30:07]

"it is necessary"

[iposva, 2008/12/17 17:39:24]

Done.

+// if there is more than one thread running. If not a single JavaScript can

[Erik Corry, 2008/12/17 14:30:07]

"If not, a single JavaScript thread can"

[iposva, 2008/12/17 17:39:24]

Done.

+// take full control of V8 and not allow other threads to run.
 class ContextSwitcher: public Thread {
  public:
-  void Run();
+  // Set the preemption interval for the ContextSwitcher thread.
   static void StartPreemption(int every_n_ms);
+
+  // Stop sending preemption requests to threads.
   static void StopPreemption();
+
+  // Preempted thread needs to calls back to the ContextSwitcher to acknowlege

[Erik Corry, 2008/12/17 14:30:07]

"to call back"

[iposva, 2008/12/17 17:39:24]

Done.

+  // the handling of a preemption request.
   static void PreemptionReceived();
+
  private:
   explicit ContextSwitcher(int every_n_ms);
-  void WaitForPreemption();
-  void Stop();
-  Semaphore* preemption_semaphore_;
+
+  void Run();
+
   bool keep_going_;
   int sleep_ms_;
+
+  static ContextSwitcher* singleton_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_V8THREADS_H_