]> git.saurik.com Git - apple/xnu.git/blobdiff - iokit/Kernel/IOWorkLoop.cpp
xnu-1699.22.73.tar.gz
[apple/xnu.git] / iokit / Kernel / IOWorkLoop.cpp
index c32a565f6861d4fa71bf875d51c4033870f0bebd..51045a234cfe441eb52768a62bf6af452a3e72a9 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998-2007 Apple Inc. All rights reserved.
+ * Copyright (c) 1998-2010 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
@@ -56,31 +56,81 @@ OSMetaClassDefineReservedUnused(IOWorkLoop, 6);
 OSMetaClassDefineReservedUnused(IOWorkLoop, 7);
 
 enum IOWorkLoopState { kLoopRestart = 0x1, kLoopTerminate = 0x2 };
-#ifdef __ppc__
-static inline void SETP(void *addr, unsigned int flag)
-    { unsigned int *num = (unsigned int *) addr; *num |= flag; }
-static inline void CLRP(void *addr, unsigned int flag)
-    { unsigned int *num = (unsigned int *) addr; *num &= ~flag; }
-static inline bool ISSETP(void *addr, unsigned int flag)
-    { unsigned int *num = (unsigned int *) addr; return (*num & flag) != 0; }
-#else
 static inline void SETP(void *addr, unsigned int flag)
     { unsigned char *num = (unsigned char *) addr; *num |= flag; }
 static inline void CLRP(void *addr, unsigned int flag)
     { unsigned char *num = (unsigned char *) addr; *num &= ~flag; }
 static inline bool ISSETP(void *addr, unsigned int flag)
     { unsigned char *num = (unsigned char *) addr; return (*num & flag) != 0; }
-#endif
 
 #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); \
+} while(0)
+
+#define IOStatisticsCloseGate() \
+do { \
+       IOStatistics::countWorkLoopCloseGate(reserved->counter); \
+} 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 */
 
 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 DEBUG
+       OSBacktrace ( reserved->allocationBacktrace, sizeof ( reserved->allocationBacktrace ) / sizeof ( reserved->allocationBacktrace[0] ) );
+#endif
+       
     if ( gateLock == NULL ) {
         if ( !( gateLock = IORecursiveLockAlloc()) )
             return false;
@@ -93,6 +143,13 @@ bool IOWorkLoop::init()
         workToDo = false;
     }
 
+    if (!reserved) {
+        reserved = IONew(ExpansionData, 1);
+        reserved->options = 0;
+    }
+       
+    IOStatisticsRegisterCounter();
+
     if ( controlG == NULL ) {
         controlG = IOCommandGate::commandGate(
             this,
@@ -132,23 +189,24 @@ IOWorkLoop::workLoop()
 IOWorkLoop *
 IOWorkLoop::workLoopWithOptions(IOOptionBits options)
 {
-    IOWorkLoop *me = new IOWorkLoop;
-
-    if (me && options) {
-       me->reserved = IONew(ExpansionData, 1);
-       if (!me->reserved) {
-           me->release();
-           return 0;
+       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;
        }
-       me->reserved->options = options;
-    }
-
-    if (me && !me->init()) {
-        me->release();
-        return 0;
-    }
-
-    return me;
+       
+       if (me && !me->init()) {
+               me->release();
+               return 0;
+       }
+       
+       return me;
 }
 
 // Free is called twice:
@@ -187,6 +245,14 @@ void IOWorkLoop::free()
         }
         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.
@@ -205,6 +271,9 @@ void IOWorkLoop::free()
            IORecursiveLockFree(gateLock);
            gateLock = 0;
        }
+       
+       IOStatisticsUnregisterCounter();
+       
        if (reserved) {
            IODelete(reserved, ExpansionData, 1);
            reserved = 0;
@@ -230,6 +299,9 @@ void IOWorkLoop::enableAllEventSources() const
 
     for (event = eventChain; event; event = event->getNext())
         event->enable();
+
+    for (event = passiveEventChain; event; event = event->getNext())
+        event->enable();
 }
 
 void IOWorkLoop::disableAllEventSources() const
@@ -237,6 +309,10 @@ void IOWorkLoop::disableAllEventSources() const
     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();
 }
@@ -244,7 +320,7 @@ void IOWorkLoop::disableAllEventSources() const
 void IOWorkLoop::enableAllInterrupts() const
 {
     IOEventSource *event;
-
+       
     for (event = eventChain; event; event = event->getNext())
         if (OSDynamicCast(IOInterruptEventSource, event))
             event->enable();
@@ -253,43 +329,12 @@ void IOWorkLoop::enableAllInterrupts() const
 void IOWorkLoop::disableAllInterrupts() const
 {
     IOEventSource *event;
-
+       
     for (event = eventChain; event; event = event->getNext())
         if (OSDynamicCast(IOInterruptEventSource, event))
             event->disable();
 }
 
-#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 */
 
 /* virtual */ bool IOWorkLoop::runEventSources()
 {
@@ -299,42 +344,43 @@ do {                                                                      \
     
     closeGate();
     if (ISSETP(&fFlags, kLoopTerminate))
-       goto abort;
-
+               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);
-       for (IOEventSource *evnt = eventChain; evnt; evnt = evnt->getNext()) {
-
-               if (traceES)
-                       IOTimeStampStartConstant(IODBG_WORKLOOP(IOWL_CLIENT), (uintptr_t) this, (uintptr_t) evnt);
+               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()) {
                        
-           more |= evnt->checkForWork();
+                       if (traceES)
+                               IOTimeStampStartConstant(IODBG_WORKLOOP(IOWL_CLIENT), (uintptr_t) this, (uintptr_t) evnt);
                        
-               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;
-           }
-       }
+                       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;
@@ -403,27 +449,41 @@ void IOWorkLoop::signalWorkAvailable()
 
 void IOWorkLoop::openGate()
 {
+    IOStatisticsOpenGate();
     IORecursiveLockUnlock(gateLock);
 }
 
 void IOWorkLoop::closeGate()
 {
     IORecursiveLockLock(gateLock);
+    IOStatisticsCloseGate();
 }
 
 bool IOWorkLoop::tryCloseGate()
 {
-    return IORecursiveLockTryLock(gateLock) != 0;
+    bool res = (IORecursiveLockTryLock(gateLock) != 0);
+    if (res) {
+        IOStatisticsCloseGate();
+    }
+    return res;
 }
 
 int IOWorkLoop::sleepGate(void *event, UInt32 interuptibleType)
 {
-    return IORecursiveLockSleep(gateLock, event, interuptibleType);
+    int res; 
+    IOStatisticsOpenGate();
+    res = IORecursiveLockSleep(gateLock, event, interuptibleType);
+    IOStatisticsCloseGate();
+    return res;
 }
 
 int IOWorkLoop::sleepGate(void *event, AbsoluteTime deadline, UInt32 interuptibleType)
 {
-    return IORecursiveLockSleepDeadline(gateLock, event, deadline, interuptibleType);
+    int res; 
+    IOStatisticsOpenGate();
+    res = IORecursiveLockSleepDeadline(gateLock, event, deadline, interuptibleType);
+    IOStatisticsCloseGate();
+    return res;
 }
 
 void IOWorkLoop::wakeupGate(void *event, bool oneThread)
@@ -460,41 +520,82 @@ IOReturn IOWorkLoop::_maintRequest(void *inC, void *inD, void *, void *)
             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;
     
-            if (!eventChain)
-                eventChain = inEvent;
+                       for (event = eventChain; (next = event->getNext()); event = next)
+                       ;
+                       event->setNext(inEvent);
+                       
+               }
+               
+            }
             else {
-                IOEventSource *event, *next;
+               
+                   if (!passiveEventChain)
+                   passiveEventChain = inEvent;
+                   else {
+                   IOEventSource *event, *next;
     
-                for (event = eventChain; (next = event->getNext()); event = next)
-                    ;
-                event->setNext(inEvent);
+                       for (event = passiveEventChain; (next = event->getNext()); event = next)
+                       ;
+                       event->setNext(inEvent);
+                       
+               }
+               
             }
+            IOStatisticsAttachEventSource();
         }
         break;
 
     case mRemoveEvent:
         if (inEvent->getWorkLoop()) {
-            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());
-            }
-    
+               if (eventSourcePerformsWork(inEvent)) {
+                               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());
+                               }
+               }
+               else {
+                               if (passiveEventChain == inEvent)
+                                       passiveEventChain = inEvent->getNext();
+                               else {
+                                       IOEventSource *event, *next;
+               
+                                       event = passiveEventChain;
+                                       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();
             SETP(&fFlags, kLoopRestart);
+            IOStatisticsDetachEventSource();
         }
         break;
 
@@ -504,3 +605,40 @@ IOReturn IOWorkLoop::_maintRequest(void *inC, void *inD, void *, void *)
 
     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;
+}