298 |
|
else if (s.waiter == null) |
299 |
|
s.waiter = w; |
300 |
|
else if (mode != TIMEOUT) { |
301 |
< |
// LockSupport.park(this); |
302 |
< |
LockSupport.park(); // allows run on java5 |
301 |
> |
LockSupport.park(this); |
302 |
|
s.waiter = null; |
303 |
|
spins = -1; |
304 |
|
} |
305 |
|
else if (nanos > spinForTimeoutThreshold) { |
306 |
< |
// LockSupport.parkNanos(this, nanos); |
308 |
< |
LockSupport.parkNanos(nanos); |
306 |
> |
LockSupport.parkNanos(this, nanos); |
307 |
|
s.waiter = null; |
308 |
|
spins = -1; |
309 |
|
} |
728 |
|
|
729 |
|
|
730 |
|
// Support for resetting head/tail while deserializing |
731 |
+ |
private void resetHeadAndTail() { |
732 |
+ |
QNode dummy = new QNode(null, false); |
733 |
+ |
_unsafe.putObjectVolatile(this, headOffset, |
734 |
+ |
new PaddedAtomicReference<QNode>(dummy)); |
735 |
+ |
_unsafe.putObjectVolatile(this, tailOffset, |
736 |
+ |
new PaddedAtomicReference<QNode>(dummy)); |
737 |
+ |
_unsafe.putObjectVolatile(this, cleanMeOffset, |
738 |
+ |
new PaddedAtomicReference<QNode>(null)); |
739 |
+ |
} |
740 |
|
|
741 |
|
// Temporary Unsafe mechanics for preliminary release |
742 |
+ |
private static Unsafe getUnsafe() throws Throwable { |
743 |
+ |
try { |
744 |
+ |
return Unsafe.getUnsafe(); |
745 |
+ |
} catch (SecurityException se) { |
746 |
+ |
try { |
747 |
+ |
return java.security.AccessController.doPrivileged |
748 |
+ |
(new java.security.PrivilegedExceptionAction<Unsafe>() { |
749 |
+ |
public Unsafe run() throws Exception { |
750 |
+ |
return getUnsafePrivileged(); |
751 |
+ |
}}); |
752 |
+ |
} catch (java.security.PrivilegedActionException e) { |
753 |
+ |
throw e.getCause(); |
754 |
+ |
} |
755 |
+ |
} |
756 |
+ |
} |
757 |
+ |
|
758 |
+ |
private static Unsafe getUnsafePrivileged() |
759 |
+ |
throws NoSuchFieldException, IllegalAccessException { |
760 |
+ |
Field f = Unsafe.class.getDeclaredField("theUnsafe"); |
761 |
+ |
f.setAccessible(true); |
762 |
+ |
return (Unsafe) f.get(null); |
763 |
+ |
} |
764 |
+ |
|
765 |
+ |
private static long fieldOffset(String fieldName) |
766 |
+ |
throws NoSuchFieldException { |
767 |
+ |
return _unsafe.objectFieldOffset |
768 |
+ |
(LinkedTransferQueue.class.getDeclaredField(fieldName)); |
769 |
+ |
} |
770 |
+ |
|
771 |
|
private static final Unsafe _unsafe; |
772 |
|
private static final long headOffset; |
773 |
|
private static final long tailOffset; |
774 |
|
private static final long cleanMeOffset; |
775 |
|
static { |
776 |
|
try { |
777 |
< |
if (LinkedTransferQueue.class.getClassLoader() != null) { |
778 |
< |
Field f = Unsafe.class.getDeclaredField("theUnsafe"); |
779 |
< |
f.setAccessible(true); |
780 |
< |
_unsafe = (Unsafe)f.get(null); |
781 |
< |
} |
746 |
< |
else |
747 |
< |
_unsafe = Unsafe.getUnsafe(); |
748 |
< |
headOffset = _unsafe.objectFieldOffset |
749 |
< |
(LinkedTransferQueue.class.getDeclaredField("head")); |
750 |
< |
tailOffset = _unsafe.objectFieldOffset |
751 |
< |
(LinkedTransferQueue.class.getDeclaredField("tail")); |
752 |
< |
cleanMeOffset = _unsafe.objectFieldOffset |
753 |
< |
(LinkedTransferQueue.class.getDeclaredField("cleanMe")); |
754 |
< |
} catch (Exception e) { |
777 |
> |
_unsafe = getUnsafe(); |
778 |
> |
headOffset = fieldOffset("head"); |
779 |
> |
tailOffset = fieldOffset("tail"); |
780 |
> |
cleanMeOffset = fieldOffset("cleanMe"); |
781 |
> |
} catch (Throwable e) { |
782 |
|
throw new RuntimeException("Could not initialize intrinsics", e); |
783 |
|
} |
784 |
|
} |
785 |
|
|
759 |
– |
private void resetHeadAndTail() { |
760 |
– |
QNode dummy = new QNode(null, false); |
761 |
– |
_unsafe.putObjectVolatile(this, headOffset, |
762 |
– |
new PaddedAtomicReference<QNode>(dummy)); |
763 |
– |
_unsafe.putObjectVolatile(this, tailOffset, |
764 |
– |
new PaddedAtomicReference<QNode>(dummy)); |
765 |
– |
_unsafe.putObjectVolatile(this, cleanMeOffset, |
766 |
– |
new PaddedAtomicReference<QNode>(null)); |
767 |
– |
|
768 |
– |
} |
769 |
– |
|
786 |
|
} |