Fix issue 142

src/v8threads.h

Index: src/v8threads.h
===================================================================
--- src/v8threads.h	(revision 981)
+++ src/v8threads.h	(working copy)
@@ -87,19 +87,31 @@
 };
 
 
+// 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