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iokit/Kernel/IOWorkLoop.cpp xnu-3789.31.2 xnu-344
--- xnu/xnu-3789.31.2/iokit/Kernel/IOWorkLoop.cpp
+++ xnu/xnu-344/iokit/Kernel/IOWorkLoop.cpp
@@ -1,56 +1,46 @@
 /*
- * Copyright (c) 1998-2010 Apple Inc. All rights reserved.
+ * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ * @APPLE_LICENSE_HEADER_START@
  * 
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. The rights granted to you under the License
- * may not be used to create, or enable the creation or redistribution of,
- * unlawful or unlicensed copies of an Apple operating system, or to
- * circumvent, violate, or enable the circumvention or violation of, any
- * terms of an Apple operating system software license agreement.
+ * The contents of this file constitute Original Code as defined in and
+ * are subject to the Apple Public Source License Version 1.1 (the
+ * "License").  You may not use this file except in compliance with the
+ * License.  Please obtain a copy of the License at
+ * http://www.apple.com/publicsource and read it before using this file.
  * 
- * Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this file.
- * 
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * This Original Code and all software distributed under the License are
+ * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
  * 
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ * @APPLE_LICENSE_HEADER_END@
  */
-
-#include <pexpert/pexpert.h>
+/*
+Copyright (c) 1998 Apple Computer, Inc.  All rights reserved.
+
+HISTORY
+    1998-7-13	Godfrey van der Linden(gvdl)
+        Created.
+*/
 #include <IOKit/IOWorkLoop.h>
 #include <IOKit/IOEventSource.h>
 #include <IOKit/IOInterruptEventSource.h>
 #include <IOKit/IOCommandGate.h>
-#include <IOKit/IOCommandPool.h>
 #include <IOKit/IOTimeStamp.h>
-#include <IOKit/IOKitDebug.h>
-#include <libkern/OSDebug.h>
-#include <kern/thread.h>
 
 #define super OSObject
 
 OSDefineMetaClassAndStructors(IOWorkLoop, OSObject);
 
 // Block of unused functions intended for future use
-#if __LP64__
-OSMetaClassDefineReservedUnused(IOWorkLoop, 0);
+OSMetaClassDefineReservedUsed(IOWorkLoop, 0);
+
 OSMetaClassDefineReservedUnused(IOWorkLoop, 1);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 2);
-#else
-OSMetaClassDefineReservedUsed(IOWorkLoop, 0);
-OSMetaClassDefineReservedUsed(IOWorkLoop, 1);
-OSMetaClassDefineReservedUsed(IOWorkLoop, 2);
-#endif
 OSMetaClassDefineReservedUnused(IOWorkLoop, 3);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 4);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 5);
@@ -59,149 +49,71 @@
 
 enum IOWorkLoopState { kLoopRestart = 0x1, kLoopTerminate = 0x2 };
 static inline void SETP(void *addr, unsigned int flag)
-    { unsigned char *num = (unsigned char *) addr; *num |= flag; }
+    { unsigned int *num = (unsigned int *) addr; *num |= flag; }
 static inline void CLRP(void *addr, unsigned int flag)
-    { unsigned char *num = (unsigned char *) addr; *num &= ~flag; }
+    { unsigned int *num = (unsigned int *) addr; *num &= ~flag; }
 static inline bool ISSETP(void *addr, unsigned int flag)
-    { unsigned char *num = (unsigned char *) addr; return (*num & flag) != 0; }
+    { unsigned int *num = (unsigned int *) addr; return (*num & flag) != 0; }
 
 #define fFlags loopRestart
 
-#define passiveEventChain	reserved->passiveEventChain
-
-#if IOKITSTATS
-
-#define IOStatisticsRegisterCounter() \
-do { \
-	reserved->counter = IOStatistics::registerWorkLoop(this); \
-} while(0)
-
-#define IOStatisticsUnregisterCounter() \
-do { \
-	if (reserved) \
-		IOStatistics::unregisterWorkLoop(reserved->counter); \
-} while(0)
-
-#define IOStatisticsOpenGate() \
-do { \
-	IOStatistics::countWorkLoopOpenGate(reserved->counter); \
-        if (reserved->lockInterval) lockTime();                 \
-} while(0)
-#define IOStatisticsCloseGate() \
-do { \
-	IOStatistics::countWorkLoopCloseGate(reserved->counter);                    \
-        if (reserved->lockInterval) reserved->lockTime = mach_absolute_time();      \
-} while(0)
-
-#define IOStatisticsAttachEventSource() \
-do { \
-	IOStatistics::attachWorkLoopEventSource(reserved->counter, inEvent->reserved->counter); \
-} while(0)
-
-#define IOStatisticsDetachEventSource() \
-do { \
-	IOStatistics::detachWorkLoopEventSource(reserved->counter, inEvent->reserved->counter); \
-} while(0)
-
-#else
-
-#define IOStatisticsRegisterCounter()
-#define IOStatisticsUnregisterCounter()
-#define IOStatisticsOpenGate()
-#define IOStatisticsCloseGate()
-#define IOStatisticsAttachEventSource()
-#define IOStatisticsDetachEventSource()
-
-#endif /* IOKITSTATS */
+extern "C" extern void stack_privilege( thread_t thread);
+
+void IOWorkLoop::launchThreadMain(void *self)
+{
+    register thread_t mythread = current_thread();
+
+    // Make sure that this thread always has a kernel stack
+    stack_privilege(mythread);
+    thread_set_cont_arg((int) self);
+    threadMainContinuation();
+}
 
 bool IOWorkLoop::init()
 {
-    // The super init and gateLock allocation MUST be done first.
+    // The super init and gateLock allocation MUST be done first
     if ( !super::init() )
         return false;
-	
-	// Allocate our ExpansionData if it hasn't been allocated already.
-	if ( !reserved )
-	{
-		reserved = IONew(ExpansionData,1);
-		if ( !reserved )
-			return false;
-		
-		bzero(reserved,sizeof(ExpansionData));
-	}
-
-    if ( gateLock == NULL ) {
-        if ( !( gateLock = IORecursiveLockAlloc()) )
-            return false;
-    }
-	
-    if ( workToDoLock == NULL ) {
-        if ( !(workToDoLock = IOSimpleLockAlloc()) )
-            return false;
-        IOSimpleLockInit(workToDoLock);
-        workToDo = false;
-    }
-
-    IOStatisticsRegisterCounter();
-
-    if ( controlG == NULL ) {
-        controlG = IOCommandGate::commandGate(
-            this,
-            OSMemberFunctionCast(
-                IOCommandGate::Action,
-                this,
-                &IOWorkLoop::_maintRequest));
-
-        if ( !controlG )
-            return false;
-        // Point the controlGate at the workLoop.  Usually addEventSource
-        // does this automatically.  The problem is in this case addEventSource
-        // uses the control gate and it has to be bootstrapped.
-        controlG->setWorkLoop(this);
-        if (addEventSource(controlG) != kIOReturnSuccess)
-            return false;
-    }
-
-    if ( workThread == NULL ) {
-        thread_continue_t cptr = OSMemberFunctionCast(
-            thread_continue_t,
-            this,
-            &IOWorkLoop::threadMain);
-        if (KERN_SUCCESS != kernel_thread_start(cptr, this, &workThread))
-            return false;
-    }
-
-    (void) thread_set_tag(workThread, THREAD_TAG_IOWORKLOOP);
+
+    if ( !(gateLock = IORecursiveLockAlloc()) )
+        return false;
+
+    if ( !(workToDoLock = IOSimpleLockAlloc()) )
+        return false;
+
+    controlG = IOCommandGate::
+	commandGate(this, (IOCommandGate::Action) &IOWorkLoop::_maintRequest);
+    if ( !controlG )
+        return false;
+
+    IOSimpleLockInit(workToDoLock);
+    workToDo = false;
+
+    // Point the controlGate at the workLoop.  Usually addEventSource
+    // does this automatically.  The problem is in this case addEventSource
+    // uses the control gate and it has to be bootstrapped.
+    controlG->setWorkLoop(this);
+    if (addEventSource(controlG) != kIOReturnSuccess)
+        return false;
+
+    workThread = IOCreateThread(launchThreadMain, (void *) this);
+    if (!workThread)
+        return false;
+
     return true;
 }
 
 IOWorkLoop *
 IOWorkLoop::workLoop()
 {
-    return IOWorkLoop::workLoopWithOptions(0);
-}
-
-IOWorkLoop *
-IOWorkLoop::workLoopWithOptions(IOOptionBits options)
-{
-	IOWorkLoop *me = new IOWorkLoop;
-	
-	if (me && options) {
-		me->reserved = IONew(ExpansionData,1);
-		if (!me->reserved) {
-			me->release();
-			return 0;
-		}
-		bzero(me->reserved,sizeof(ExpansionData));
-		me->reserved->options = options;
-	}
-	
-	if (me && !me->init()) {
-		me->release();
-		return 0;
-	}
-	
-	return me;
+    IOWorkLoop *me = new IOWorkLoop;
+
+    if (me && !me->init()) {
+        me->free();
+        return 0;
+    }
+
+    return me;
 }
 
 // Free is called twice:
@@ -214,7 +126,7 @@
 	IOInterruptState is;
 
 	// If we are here then we must be trying to shut down this work loop
-	// in this case disable all of the event source, mark the loop
+	// in this case disable all of the event source, mark the loop for
 	// as terminating and wakeup the work thread itself and return
 	// Note: we hold the gate across the entire operation mainly for the 
 	// benefit of our event sources so we can disable them cleanly.
@@ -240,20 +152,11 @@
         }
         eventChain = 0;
 
-        for (event = passiveEventChain; event; event = next) {
-            next = event->getNext();
-            event->setWorkLoop(0);
-            event->setNext(0);
-            event->release();
-        }
-        passiveEventChain = 0;
-
-	// Either we have a partial initialization to clean up
-	// or the workThread itself is performing hari-kari.
-	// Either way clean up all of our resources and return.
+	// Either we have a partial initialisation to clean up
+	// or we the workThread itself is performing hari-kari.
+	// either way clean up all of our resources and return.
 	
 	if (controlG) {
-	    controlG->workLoop = 0;
 	    controlG->release();
 	    controlG = 0;
 	}
@@ -267,13 +170,6 @@
 	    IORecursiveLockFree(gateLock);
 	    gateLock = 0;
 	}
-	
-	IOStatisticsUnregisterCounter();
-	
-	if (reserved) {
-	    IODelete(reserved, ExpansionData, 1);
-	    reserved = 0;
-	}
 
 	super::free();
     }
@@ -281,13 +177,6 @@
 
 IOReturn IOWorkLoop::addEventSource(IOEventSource *newEvent)
 {
-    if ((workThread)
-      && !thread_has_thread_name(workThread)
-      && (newEvent->owner)
-      && !OSDynamicCast(IOCommandPool, newEvent->owner)) {
-        thread_set_thread_name(workThread, newEvent->owner->getMetaClass()->getClassName());
-    }
-
     return controlG->runCommand((void *) mAddEvent, (void *) newEvent);
 }
     
@@ -302,9 +191,6 @@
 
     for (event = eventChain; event; event = event->getNext())
         event->enable();
-
-    for (event = passiveEventChain; event; event = event->getNext())
-        event->enable();
 }
 
 void IOWorkLoop::disableAllEventSources() const
@@ -312,10 +198,6 @@
     IOEventSource *event;
 
     for (event = eventChain; event; event = event->getNext())
-		event->disable();
-	
-	/* NOTE: controlG is in passiveEventChain since it's an IOCommandGate */
-    for (event = passiveEventChain; event; event = event->getNext())
         if (event != controlG)	// Don't disable the control gate
             event->disable();
 }
@@ -323,7 +205,7 @@
 void IOWorkLoop::enableAllInterrupts() const
 {
     IOEventSource *event;
-	
+
     for (event = eventChain; event; event = event->getNext())
         if (OSDynamicCast(IOInterruptEventSource, event))
             event->enable();
@@ -332,80 +214,94 @@
 void IOWorkLoop::disableAllInterrupts() const
 {
     IOEventSource *event;
-	
+
     for (event = eventChain; event; event = event->getNext())
         if (OSDynamicCast(IOInterruptEventSource, event))
             event->disable();
 }
 
-
-/* virtual */ bool IOWorkLoop::runEventSources()
-{
-    bool res = false;
-    bool traceWL = (gIOKitTrace & kIOTraceWorkLoops) ? true : false;
-    bool traceES = (gIOKitTrace & kIOTraceEventSources) ? true : false;
-    
-    closeGate();
-    if (ISSETP(&fFlags, kLoopTerminate))
-		goto abort;
-	
-    if (traceWL)
-    	IOTimeStampStartConstant(IODBG_WORKLOOP(IOWL_WORK), (uintptr_t) this);
-	
-    bool more;
-    do {
-		CLRP(&fFlags, kLoopRestart);
-		more = false;
-		IOInterruptState is = IOSimpleLockLockDisableInterrupt(workToDoLock);
-		workToDo = false;
-		IOSimpleLockUnlockEnableInterrupt(workToDoLock, is);
-		/* NOTE: only loop over event sources in eventChain. Bypass "passive" event sources for performance */
-		for (IOEventSource *evnt = eventChain; evnt; evnt = evnt->getNext()) {
-			
-			if (traceES)
-				IOTimeStampStartConstant(IODBG_WORKLOOP(IOWL_CLIENT), (uintptr_t) this, (uintptr_t) evnt);
-			
-			more |= evnt->checkForWork();
-			
-			if (traceES)
-				IOTimeStampEndConstant(IODBG_WORKLOOP(IOWL_CLIENT), (uintptr_t) this, (uintptr_t) evnt);
-			
-			if (ISSETP(&fFlags, kLoopTerminate))
-				goto abort;
-			else if (fFlags & kLoopRestart) {
-				more = true;
-				break;
-			}
-		}
-    } while (more);
-	
-    res = true;
-	
-    if (traceWL)
-    	IOTimeStampEndConstant(IODBG_WORKLOOP(IOWL_WORK), (uintptr_t) this);
-	
-abort:
-    openGate();
-    return res;
-}
-
-/* virtual */ void IOWorkLoop::threadMain()
-{
-restartThread:
-    do {
-	if ( !runEventSources() )
+#if KDEBUG
+#define IOTimeClientS()							\
+do {									\
+    IOTimeStampStart(IODBG_WORKLOOP(IOWL_CLIENT),			\
+                     (unsigned int) this, (unsigned int) event);	\
+} while(0)
+
+#define IOTimeClientE()							\
+do {									\
+    IOTimeStampEnd(IODBG_WORKLOOP(IOWL_CLIENT),				\
+                   (unsigned int) this, (unsigned int) event);		\
+} while(0)
+
+#define IOTimeWorkS()							\
+do {									\
+    IOTimeStampStart(IODBG_WORKLOOP(IOWL_WORK),	(unsigned int) this);	\
+} while(0)
+
+#define IOTimeWorkE()							\
+do {									\
+    IOTimeStampEnd(IODBG_WORKLOOP(IOWL_WORK),(unsigned int) this);	\
+} while(0)
+
+#else /* !KDEBUG */
+
+#define IOTimeClientS()
+#define IOTimeClientE()
+#define IOTimeWorkS()
+#define IOTimeWorkE()
+
+#endif /* KDEBUG */
+
+void IOWorkLoop::threadMainContinuation()
+{
+  IOWorkLoop* self;
+  self = (IOWorkLoop *) thread_get_cont_arg();
+
+  self->threadMain();
+}
+
+void IOWorkLoop::threadMain()
+{
+    CLRP(&fFlags, kLoopRestart);
+
+    for (;;) {
+        bool more;
+	IOInterruptState is;
+
+    IOTimeWorkS();
+
+        closeGate();
+        if (ISSETP(&fFlags, kLoopTerminate))
 	    goto exitThread;
 
-	IOInterruptState is = IOSimpleLockLockDisableInterrupt(workToDoLock);
+        do {
+            workToDo = more = false;
+            for (IOEventSource *event = eventChain; event; event = event->getNext()) {
+
+            IOTimeClientS();
+                more |= event->checkForWork();
+            IOTimeClientE();
+
+		if (ISSETP(&fFlags, kLoopTerminate))
+		    goto exitThread;
+                else if (fFlags & kLoopRestart) {
+		    CLRP(&fFlags, kLoopRestart);
+                    continue;
+                }
+            }
+        } while (more);
+
+    IOTimeWorkE();
+
+        openGate();
+
+	is = IOSimpleLockLockDisableInterrupt(workToDoLock);
         if ( !ISSETP(&fFlags, kLoopTerminate) && !workToDo) {
 	    assert_wait((void *) &workToDo, false);
 	    IOSimpleLockUnlockEnableInterrupt(workToDoLock, is);
-	    thread_continue_t cptr = NULL;
-	    if (!reserved || !(kPreciousStack & reserved->options))
-		cptr = OSMemberFunctionCast(
-			thread_continue_t, this, &IOWorkLoop::threadMain);
-	    thread_block_parameter(cptr, this);
-	    goto restartThread;
+
+	    thread_set_cont_arg((int) this);
+	    thread_block(&threadMainContinuation);
 	    /* NOTREACHED */
 	}
 
@@ -413,15 +309,16 @@
 	// to commit suicide.  But no matter 
 	// Clear the simple lock and retore the interrupt state
 	IOSimpleLockUnlockEnableInterrupt(workToDoLock, is);
-    } while(workToDo);
+	if (workToDo)
+	    continue;
+	else
+	    break;
+    }
 
 exitThread:
-	thread_t thread = workThread;
     workThread = 0;	// Say we don't have a loop and free ourselves
     free();
-
-	thread_deallocate(thread);
-    (void) thread_terminate(thread);
+    IOExitThread();
 }
 
 IOThread IOWorkLoop::getThread() const
@@ -452,41 +349,22 @@
 
 void IOWorkLoop::openGate()
 {
-    IOStatisticsOpenGate();
     IORecursiveLockUnlock(gateLock);
 }
 
 void IOWorkLoop::closeGate()
 {
     IORecursiveLockLock(gateLock);
-    IOStatisticsCloseGate();
 }
 
 bool IOWorkLoop::tryCloseGate()
 {
-    bool res = (IORecursiveLockTryLock(gateLock) != 0);
-    if (res) {
-        IOStatisticsCloseGate();
-    }
-    return res;
+    return IORecursiveLockTryLock(gateLock) != 0;
 }
 
 int IOWorkLoop::sleepGate(void *event, UInt32 interuptibleType)
 {
-    int res; 
-    IOStatisticsOpenGate();
-    res = IORecursiveLockSleep(gateLock, event, interuptibleType);
-    IOStatisticsCloseGate();
-    return res;
-}
-
-int IOWorkLoop::sleepGate(void *event, AbsoluteTime deadline, UInt32 interuptibleType)
-{
-    int res; 
-    IOStatisticsOpenGate();
-    res = IORecursiveLockSleepDeadline(gateLock, event, deadline, interuptibleType);
-    IOStatisticsCloseGate();
-    return res;
+    return IORecursiveLockSleep(gateLock, event, interuptibleType);
 }
 
 void IOWorkLoop::wakeupGate(void *event, bool oneThread)
@@ -495,8 +373,8 @@
 }
 
 IOReturn IOWorkLoop::runAction(Action inAction, OSObject *target,
-                                  void *arg0, void *arg1,
-                                  void *arg2, void *arg3)
+                                  void *arg0 = 0, void *arg1 = 0,
+                                  void *arg2 = 0, void *arg3 = 0)
 {
     IOReturn res;
 
@@ -510,7 +388,7 @@
 
 IOReturn IOWorkLoop::_maintRequest(void *inC, void *inD, void *, void *)
 {
-    maintCommandEnum command = (maintCommandEnum) (uintptr_t) inC;
+    maintCommandEnum command = (maintCommandEnum) (vm_address_t) inC;
     IOEventSource *inEvent = (IOEventSource *) inD;
     IOReturn res = kIOReturnSuccess;
 
@@ -523,79 +401,37 @@
             inEvent->retain();
             inEvent->setWorkLoop(this);
             inEvent->setNext(0);
-
-    		/* Check if this is a passive or active event source being added */
-    		if (eventSourcePerformsWork(inEvent)) {
-    		
-	            if (!eventChain)
-    	            eventChain = inEvent;
-        	    else {
-            	    IOEventSource *event, *next;
-    
-                	for (event = eventChain; (next = event->getNext()); event = next)
-                    	;
-                	event->setNext(inEvent);
-                	
-            	}
-            	
+    
+            if (!eventChain)
+                eventChain = inEvent;
+            else {
+                IOEventSource *event, *next;
+    
+                for (event = eventChain; (next = event->getNext()); event = next)
+                    ;
+                event->setNext(inEvent);
             }
-            else {
-    		
-	            if (!passiveEventChain)
-    	            passiveEventChain = inEvent;
-        	    else {
-            	    IOEventSource *event, *next;
-    
-                	for (event = passiveEventChain; (next = event->getNext()); event = next)
-                    	;
-                	event->setNext(inEvent);
-                	
-            	}
-            	
-            }
-            IOStatisticsAttachEventSource();
         }
         break;
 
     case mRemoveEvent:
         if (inEvent->getWorkLoop()) {
-        	IOStatisticsDetachEventSource();
-    		
-        	if (eventSourcePerformsWork(inEvent)) {
-				if (eventChain == inEvent)
-					eventChain = inEvent->getNext();
-				else {
-					IOEventSource *event, *next = 0;
-		
-					event = eventChain;
-					if (event) while ((next = event->getNext()) && (next != inEvent))
-						event = next;
-		
-					if (!next) {
-						res = kIOReturnBadArgument;
-						break;
-					}
-					event->setNext(inEvent->getNext());
-				}
-    		}
-    		else {
-				if (passiveEventChain == inEvent)
-					passiveEventChain = inEvent->getNext();
-				else {
-					IOEventSource *event, *next = 0;
-		
-					event = passiveEventChain;
-					if (event) while ((next = event->getNext()) && (next != inEvent))
-						event = next;
-		
-					if (!next) {
-						res = kIOReturnBadArgument;
-						break;
-					}
-					event->setNext(inEvent->getNext());
-				}
-    		}
-    		
+            if (eventChain == inEvent)
+                eventChain = inEvent->getNext();
+            else {
+                IOEventSource *event, *next;
+    
+                event = eventChain;
+                while ((next = event->getNext()) && next != inEvent)
+                    event = next;
+    
+                if (!next) {
+                    res = kIOReturnBadArgument;
+                    break;
+                }
+                event->setNext(inEvent->getNext());
+            }
+    
             inEvent->setWorkLoop(0);
             inEvent->setNext(0);
             inEvent->release();
@@ -609,62 +445,3 @@
 
     return res;
 }
-
-bool
-IOWorkLoop::eventSourcePerformsWork(IOEventSource *inEventSource)
-{
-	bool	result = true;
-
-	/*
-	 * The idea here is to see if the subclass of IOEventSource has overridden checkForWork().
-	 * The assumption is that if you override checkForWork(), you need to be
-	 * active and not passive.
-	 *
-	 * We picked a known quantity controlG that does not override
-	 * IOEventSource::checkForWork(), namely the IOCommandGate associated with
-	 * the workloop to which this event source is getting attached.
-	 * 
-	 * We do a pointer comparison on the offset in the vtable for inNewEvent against
-	 * the offset in the vtable for inReferenceEvent. This works because
-	 * IOCommandGate's slot for checkForWork() has the address of
-	 * IOEventSource::checkForWork() in it.
-	 * 
-	 * Think of OSMemberFunctionCast yielding the value at the vtable offset for
-	 * checkForWork() here. We're just testing to see if it's the same or not.
-	 *
-	 */
-	if (controlG) {
-		void *	ptr1;
-		void *	ptr2;
-		
-		ptr1 = OSMemberFunctionCast(void*, inEventSource, &IOEventSource::checkForWork);
-		ptr2 = OSMemberFunctionCast(void*, controlG, &IOEventSource::checkForWork);
-		
-		if (ptr1 == ptr2)
-			result = false;
-	}
-	
-    return result;
-}
-
-void
-IOWorkLoop::lockTime(void)
-{
-    uint64_t time;
-    time = mach_absolute_time() - reserved->lockTime;
-    if (time > reserved->lockInterval)
-    {
-        absolutetime_to_nanoseconds(time, &time);
-        if (kTimeLockPanics & reserved->options) panic("IOWorkLoop %p lock time %qd us", this, time / 1000ULL);
-        else                     OSReportWithBacktrace("IOWorkLoop %p lock time %qd us", this, time / 1000ULL);
-    }
-}
-
-void
-IOWorkLoop::setMaximumLockTime(uint64_t interval, uint32_t options)
-{
-    IORecursiveLockLock(gateLock);
-    reserved->lockInterval = interval;
-    reserved->options = (reserved->options & ~kTimeLockPanics) | (options & kTimeLockPanics);
-    IORecursiveLockUnlock(gateLock);
-}