Loading...
--- xnu/xnu-792.6.70/libkern/c++/OSObject.cpp
+++ xnu/xnu-344.26/libkern/c++/OSObject.cpp
@@ -101,12 +101,6 @@
bool OSObject::init()
{ return true; }
-#if (!__ppc__) || (__GNUC__ < 3)
-
-// Implemented in assembler in post gcc 3.x systems as we have a problem
-// where the destructor in gcc2.95 gets 2 arguments. The second argument
-// appears to be a flag argument. I have copied the assembler from Puma xnu
-// to OSRuntimeSupport.c So for 2.95 builds use the C
void OSObject::free()
{
const OSMetaClass *meta = getMetaClass();
@@ -115,7 +109,6 @@
meta->instanceDestructed();
delete this;
}
-#endif /* (!__ppc__) || (__GNUC__ < 3) */
int OSObject::getRetainCount() const
{
@@ -124,91 +117,70 @@
void OSObject::taggedRetain(const void *tag) const
{
+#if !DEBUG
volatile UInt32 *countP = (volatile UInt32 *) &retainCount;
UInt32 inc = 1;
UInt32 origCount;
UInt32 newCount;
- // Increment the collection bucket.
+ // Increment the collecion bucket.
if ((const void *) OSTypeID(OSCollection) == tag)
inc |= (1UL<<16);
do {
origCount = *countP;
- if ( ((UInt16) origCount | 0x1) == 0xffff ) {
- const char *msg;
- if (origCount & 0x1) {
- // If count == 0xffff that means we are freeing now so we can
- // just return obviously somebody is cleaning up dangling
- // references.
- msg = "Attempting to retain a freed object";
- }
- else {
- // If count == 0xfffe then we have wrapped our reference count.
- // We should stop counting now as this reference must be
- // leaked rather than accidently wrapping around the clock and
- // freeing a very active object later.
-
+ if (-1UL == origCount)
+ // @@@ Pinot: panic("Attempting to retain a freed object");
+ return;
+
+ newCount = origCount + inc;
+ } while (!OSCompareAndSwap(origCount, newCount, (UInt32 *) countP));
+#else
+ volatile UInt32 *countP = (volatile UInt32 *) &retainCount;
+ UInt32 inc = 1;
+ UInt32 origCount;
+ UInt32 newCount;
+
+ // Increment the collecion bucket.
+ if ((const void *) OSTypeID(OSCollection) == tag)
+ inc |= (1UL<<16);
+
+ do {
+ origCount = *countP;
+ if (-1UL == origCount)
+ return; // We are freeing so leave now.
+
+ newCount = origCount + inc;
+ } while (!OSCompareAndSwap(origCount, newCount, (UInt32 *) countP));
+#endif
+}
+
+void OSObject::taggedRelease(const void *tag) const
+{
+ taggedRelease(tag, 1);
+}
+
+void OSObject::taggedRelease(const void *tag, const int when) const
+{
#if !DEBUG
- break; // Break out of update loop which pegs the reference
-#else DEBUG
- // @@@ gvdl: eventually need to make this panic optional
- // based on a boot argument i.e. debug= boot flag
- msg = "About to wrap the reference count, reference leak?";
-#endif /* !DEBUG */
- }
- panic("OSObject::refcount: %s", msg);
- }
-
- newCount = origCount + inc;
- } while (!OSCompareAndSwap(origCount, newCount, (UInt32 *) countP));
-}
-
-void OSObject::taggedRelease(const void *tag) const
-{
- taggedRelease(tag, 1);
-}
-
-void OSObject::taggedRelease(const void *tag, const int when) const
-{
volatile UInt32 *countP = (volatile UInt32 *) &retainCount;
UInt32 dec = 1;
UInt32 origCount;
UInt32 newCount;
UInt32 actualCount;
- // Increment the collection bucket.
+ // Increment the collecion bucket.
if ((const void *) OSTypeID(OSCollection) == tag)
dec |= (1UL<<16);
do {
origCount = *countP;
-
- if ( ((UInt16) origCount | 0x1) == 0xffff ) {
- if (origCount & 0x1) {
- // If count == 0xffff that means we are freeing now so we can
- // just return obviously somebody is cleaning up some dangling
- // references. So we blow out immediately.
- return;
- }
- else {
- // If count == 0xfffe then we have wrapped our reference
- // count. We should stop counting now as this reference must be
- // leaked rather than accidently freeing an active object later.
-
-#if !DEBUG
- return; // return out of function which pegs the reference
-#else DEBUG
- // @@@ gvdl: eventually need to make this panic optional
- // based on a boot argument i.e. debug= boot flag
- panic("OSObject::refcount: %s",
- "About to unreference a pegged object, reference leak?");
-#endif /* !DEBUG */
- }
- }
+ if (-1UL == origCount)
+ return; // We are freeing already leave now.
+
actualCount = origCount - dec;
- if ((UInt16) actualCount < when)
- newCount = 0xffff;
+ if ((SInt16) actualCount < when)
+ newCount = (UInt32) -1;
else
newCount = actualCount;
@@ -227,8 +199,49 @@
getClassName(this));
// Check for a 'free' condition and that if we are first through
- if (newCount == 0xffff)
+ if ((UInt32) -1 == newCount)
((OSObject *) this)->free();
+#else
+ // @@@ Pinot: Need to update the debug build release code.
+ volatile UInt32 *countP = (volatile UInt32 *) &retainCount;
+ UInt32 dec = 1;
+ UInt32 origCount;
+ UInt32 newCount;
+
+ // Increment the collecion bucket.
+ if ((const void *) OSTypeID(OSCollection) == tag)
+ dec |= (1UL<<16);
+
+ do {
+ origCount = *countP;
+ if (-1UL == origCount)
+ return; // We are freeing already leave now.
+
+ newCount = origCount - dec;
+ } while (!OSCompareAndSwap(origCount, newCount, (UInt32 *) countP));
+
+ //
+ // This panic means that we have just attempted to release an object
+ // who's retain count has gone to less than the number of collections
+ // it is a member off. Take a panic immediately.
+ // In Fact the panic MAY not be a registry corruption but it is
+ // ALWAYS the wrong thing to do. I call it a registry corruption 'cause
+ // the registry is the biggest single use of a network of collections.
+ //
+ if ((UInt16) newCount < (newCount >> 16))
+ panic("A driver releasing a(n) %s has corrupted the registry\n",
+ getClassName(this));
+
+ // Check for a release too many
+ if ((SInt16) newCount < 0)
+ panic("An object has had a release too many\n",
+ getClassName(this));
+
+ // Check for a 'free' condition and that if we are first through
+ if ((SInt16) newCount < when
+ && OSCompareAndSwap(newCount, -1UL, (UInt32 *) countP))
+ ((OSObject *) this)->free();
+#endif
}
void OSObject::release() const