8047125: (ref) More phantom object references
Reviewed-by: mchung, dfuchs, ahgross, jmasa, brutisso, mgerdin
Contributed-by: kim.barrett@oracle.com
--- a/hotspot/src/share/vm/classfile/systemDictionary.cpp Tue Aug 19 11:17:36 2014 +0200
+++ b/hotspot/src/share/vm/classfile/systemDictionary.cpp Fri Sep 26 17:48:10 2014 -0400
@@ -1905,11 +1905,12 @@
InstanceKlass::cast(WK_KLASS(Reference_klass))->set_reference_type(REF_OTHER);
InstanceRefKlass::update_nonstatic_oop_maps(WK_KLASS(Reference_klass));
- initialize_wk_klasses_through(WK_KLASS_ENUM_NAME(PhantomReference_klass), scan, CHECK);
+ initialize_wk_klasses_through(WK_KLASS_ENUM_NAME(Cleaner_klass), scan, CHECK);
InstanceKlass::cast(WK_KLASS(SoftReference_klass))->set_reference_type(REF_SOFT);
InstanceKlass::cast(WK_KLASS(WeakReference_klass))->set_reference_type(REF_WEAK);
InstanceKlass::cast(WK_KLASS(FinalReference_klass))->set_reference_type(REF_FINAL);
InstanceKlass::cast(WK_KLASS(PhantomReference_klass))->set_reference_type(REF_PHANTOM);
+ InstanceKlass::cast(WK_KLASS(Cleaner_klass))->set_reference_type(REF_CLEANER);
// JSR 292 classes
WKID jsr292_group_start = WK_KLASS_ENUM_NAME(MethodHandle_klass);
--- a/hotspot/src/share/vm/classfile/systemDictionary.hpp Tue Aug 19 11:17:36 2014 +0200
+++ b/hotspot/src/share/vm/classfile/systemDictionary.hpp Fri Sep 26 17:48:10 2014 -0400
@@ -128,6 +128,7 @@
do_klass(WeakReference_klass, java_lang_ref_WeakReference, Pre ) \
do_klass(FinalReference_klass, java_lang_ref_FinalReference, Pre ) \
do_klass(PhantomReference_klass, java_lang_ref_PhantomReference, Pre ) \
+ do_klass(Cleaner_klass, sun_misc_Cleaner, Pre ) \
do_klass(Finalizer_klass, java_lang_ref_Finalizer, Pre ) \
\
do_klass(Thread_klass, java_lang_Thread, Pre ) \
--- a/hotspot/src/share/vm/classfile/vmSymbols.hpp Tue Aug 19 11:17:36 2014 +0200
+++ b/hotspot/src/share/vm/classfile/vmSymbols.hpp Fri Sep 26 17:48:10 2014 -0400
@@ -79,6 +79,7 @@
template(java_lang_ref_WeakReference, "java/lang/ref/WeakReference") \
template(java_lang_ref_FinalReference, "java/lang/ref/FinalReference") \
template(java_lang_ref_PhantomReference, "java/lang/ref/PhantomReference") \
+ template(sun_misc_Cleaner, "sun/misc/Cleaner") \
template(java_lang_ref_Finalizer, "java/lang/ref/Finalizer") \
template(java_lang_reflect_AccessibleObject, "java/lang/reflect/AccessibleObject") \
template(java_lang_reflect_Method, "java/lang/reflect/Method") \
--- a/hotspot/src/share/vm/memory/referenceProcessor.cpp Tue Aug 19 11:17:36 2014 +0200
+++ b/hotspot/src/share/vm/memory/referenceProcessor.cpp Fri Sep 26 17:48:10 2014 -0400
@@ -118,6 +118,7 @@
_discoveredWeakRefs = &_discoveredSoftRefs[_max_num_q];
_discoveredFinalRefs = &_discoveredWeakRefs[_max_num_q];
_discoveredPhantomRefs = &_discoveredFinalRefs[_max_num_q];
+ _discoveredCleanerRefs = &_discoveredPhantomRefs[_max_num_q];
// Initialize all entries to NULL
for (uint i = 0; i < _max_num_q * number_of_subclasses_of_ref(); i++) {
@@ -246,6 +247,13 @@
phantom_count =
process_discovered_reflist(_discoveredPhantomRefs, NULL, false,
is_alive, keep_alive, complete_gc, task_executor);
+
+ // Process cleaners, but include them in phantom statistics. We expect
+ // Cleaner references to be temporary, and don't want to deal with
+ // possible incompatibilities arising from making it more visible.
+ phantom_count +=
+ process_discovered_reflist(_discoveredCleanerRefs, NULL, false,
+ is_alive, keep_alive, complete_gc, task_executor);
}
// Weak global JNI references. It would make more sense (semantically) to
@@ -885,6 +893,7 @@
balance_queues(_discoveredWeakRefs);
balance_queues(_discoveredFinalRefs);
balance_queues(_discoveredPhantomRefs);
+ balance_queues(_discoveredCleanerRefs);
}
size_t
@@ -998,6 +1007,9 @@
case REF_PHANTOM:
list = &_discoveredPhantomRefs[id];
break;
+ case REF_CLEANER:
+ list = &_discoveredCleanerRefs[id];
+ break;
case REF_NONE:
// we should not reach here if we are an InstanceRefKlass
default:
@@ -1263,6 +1275,17 @@
preclean_discovered_reflist(_discoveredPhantomRefs[i], is_alive,
keep_alive, complete_gc, yield);
}
+
+ // Cleaner references. Included in timing for phantom references. We
+ // expect Cleaner references to be temporary, and don't want to deal with
+ // possible incompatibilities arising from making it more visible.
+ for (uint i = 0; i < _max_num_q; i++) {
+ if (yield->should_return()) {
+ return;
+ }
+ preclean_discovered_reflist(_discoveredCleanerRefs[i], is_alive,
+ keep_alive, complete_gc, yield);
+ }
}
}
@@ -1331,6 +1354,7 @@
case 1: return "WeakRef";
case 2: return "FinalRef";
case 3: return "PhantomRef";
+ case 4: return "CleanerRef";
}
ShouldNotReachHere();
return NULL;
--- a/hotspot/src/share/vm/memory/referenceProcessor.hpp Tue Aug 19 11:17:36 2014 +0200
+++ b/hotspot/src/share/vm/memory/referenceProcessor.hpp Fri Sep 26 17:48:10 2014 -0400
@@ -264,9 +264,10 @@
DiscoveredList* _discoveredWeakRefs;
DiscoveredList* _discoveredFinalRefs;
DiscoveredList* _discoveredPhantomRefs;
+ DiscoveredList* _discoveredCleanerRefs;
public:
- static int number_of_subclasses_of_ref() { return (REF_PHANTOM - REF_OTHER); }
+ static int number_of_subclasses_of_ref() { return (REF_CLEANER - REF_OTHER); }
uint num_q() { return _num_q; }
uint max_num_q() { return _max_num_q; }
--- a/hotspot/src/share/vm/memory/referenceType.hpp Tue Aug 19 11:17:36 2014 +0200
+++ b/hotspot/src/share/vm/memory/referenceType.hpp Fri Sep 26 17:48:10 2014 -0400
@@ -35,7 +35,8 @@
REF_SOFT, // Subclass of java/lang/ref/SoftReference
REF_WEAK, // Subclass of java/lang/ref/WeakReference
REF_FINAL, // Subclass of java/lang/ref/FinalReference
- REF_PHANTOM // Subclass of java/lang/ref/PhantomReference
+ REF_PHANTOM, // Subclass of java/lang/ref/PhantomReference
+ REF_CLEANER // Subclass of sun/misc/Cleaner
};
#endif // SHARE_VM_MEMORY_REFRERENCETYPE_HPP
--- a/hotspot/src/share/vm/runtime/vmStructs.cpp Tue Aug 19 11:17:36 2014 +0200
+++ b/hotspot/src/share/vm/runtime/vmStructs.cpp Fri Sep 26 17:48:10 2014 -0400
@@ -661,6 +661,7 @@
static_field(SystemDictionary, WK_KLASS(WeakReference_klass), Klass*) \
static_field(SystemDictionary, WK_KLASS(FinalReference_klass), Klass*) \
static_field(SystemDictionary, WK_KLASS(PhantomReference_klass), Klass*) \
+ static_field(SystemDictionary, WK_KLASS(Cleaner_klass), Klass*) \
static_field(SystemDictionary, WK_KLASS(Finalizer_klass), Klass*) \
static_field(SystemDictionary, WK_KLASS(Thread_klass), Klass*) \
static_field(SystemDictionary, WK_KLASS(ThreadGroup_klass), Klass*) \