Improved resuming processors based on semaphores

git-svn-id: https://svn.inf.ethz.ch/svn/lecturers/a2/trunk@7353 8c9fc860-2736-0410-a75d-ab315db34111

source/Win32.Processors.Mod

@@ -12,7 +12,7 @@ CONST Maximum* = MAX (SET) - MIN (SET) + 1;
 VAR count-: SIZE;
 
 VAR affinityMask: SET;
-VAR event: Kernel32.HANDLE;
+VAR semaphore: Kernel32.HANDLE;
 VAR thread: ARRAY Maximum OF Kernel32.HANDLE;
 
 (** Returns the unique index of the processor executing this procedure call. *)
@@ -22,14 +22,13 @@ PROCEDURE GetCurrentIndex- EXTERN "Activities.GetCurrentProcessorIndex" (): SIZE
 (** A suspended processor must be resumed by a call to the ResumeAnyProcessor procedure. *)
 PROCEDURE SuspendCurrentProcessor-;
 BEGIN {UNCOOPERATIVE, UNCHECKED}
-	ASSERT (Kernel32.WaitForSingleObject (event, Kernel32.Infinite) # Kernel32.WaitFailed);
+	ASSERT (Kernel32.WaitForSingleObject (semaphore, Kernel32.Infinite) # Kernel32.WaitFailed);
 END SuspendCurrentProcessor;
 
 (** Resumes the execution of all suspended processors. *)
 PROCEDURE ResumeAllProcessors-;
 BEGIN {UNCOOPERATIVE, UNCHECKED}
-	ASSERT (Kernel32.SetEvent (event) # 0);
-	ASSERT (Kernel32.ResetEvent (event) # 0);
+	ASSERT (Kernel32.ReleaseSemaphore (semaphore, Maximum, NIL) # 0);
 END ResumeAllProcessors;
 
 (** Starts the execution of all available processors. *)
@@ -58,8 +57,8 @@ END Start;
 PROCEDURE Initialize-;
 VAR systemAffinityMask: SET; i: SIZE; handle: Kernel32.HANDLE;
 BEGIN {UNCOOPERATIVE, UNCHECKED}
-	event := Kernel32.CreateEvent (NIL, Kernel32.True, Kernel32.False, NIL);
-	ASSERT (event # Kernel32.InvalidHandleValue);
+	semaphore := Kernel32.CreateSemaphore (NIL, 0, MAX (SIZE), NIL);
+	ASSERT (semaphore # Kernel32.InvalidHandleValue);
 
 	ASSERT (Kernel32.GetProcessAffinityMask (Kernel32.GetCurrentProcess (), ADDRESS OF affinityMask, ADDRESS OF systemAffinityMask) # 0);
 
@@ -94,7 +93,7 @@ BEGIN {UNCOOPERATIVE, UNCHECKED}
 			ASSERT (Kernel32.CloseHandle (thread[i]) # 0);
 		END;
 	END;
-	ASSERT (Kernel32.CloseHandle (event) # 0);
+	ASSERT (Kernel32.CloseHandle (semaphore) # 0);
 END Terminate;
 
 END Processors.