8299072: java_lang_ref_Reference::clear_referent should be GC agnostic

Co-authored-by: Axel Boldt-Christmas <aboldtch@openjdk.org> Reviewed-by: dholmes, shade, kbarrett
openjdk · Jan 4, 2023 · c32a34c · c32a34c · openjdk-notifier · Jan 4, 2023
1 parent ccbcea8
commit c32a34c
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Showing 5 changed files with 8 additions and 3 deletions.
diff --git a/src/hotspot/share/classfile/javaClasses.hpp b/src/hotspot/share/classfile/javaClasses.hpp
@@ -952,6 +952,7 @@ class java_lang_ref_Reference: AllStatic {
   static inline oop phantom_referent_no_keepalive(oop ref);
   static inline oop unknown_referent_no_keepalive(oop ref);
   static inline void clear_referent(oop ref);
+  static inline void clear_referent_raw(oop ref);
   static inline HeapWord* referent_addr_raw(oop ref);
   static inline oop next(oop ref);
   static inline void set_next(oop ref, oop value);

diff --git a/src/hotspot/share/classfile/javaClasses.inline.hpp b/src/hotspot/share/classfile/javaClasses.inline.hpp
@@ -152,6 +152,10 @@ oop java_lang_ref_Reference::unknown_referent_no_keepalive(oop ref) {
 }
 
 void java_lang_ref_Reference::clear_referent(oop ref) {
+  HeapAccess<ON_UNKNOWN_OOP_REF | AS_NO_KEEPALIVE>::oop_store_at(ref, _referent_offset, nullptr);
+}
+
+void java_lang_ref_Reference::clear_referent_raw(oop ref) {
   ref->obj_field_put_raw(_referent_offset, nullptr);
 }
 

diff --git a/src/hotspot/share/gc/shared/referenceProcessor.cpp b/src/hotspot/share/gc/shared/referenceProcessor.cpp
@@ -282,7 +282,7 @@ void DiscoveredListIterator::make_referent_alive() {
 }
 
 void DiscoveredListIterator::clear_referent() {
-  java_lang_ref_Reference::clear_referent(_current_discovered);
+  java_lang_ref_Reference::clear_referent_raw(_current_discovered);
 }
 
 void DiscoveredListIterator::enqueue() {

diff --git a/src/hotspot/share/gc/shenandoah/shenandoahReferenceProcessor.cpp b/src/hotspot/share/gc/shenandoah/shenandoahReferenceProcessor.cpp
@@ -90,7 +90,7 @@ static oop reference_referent(oop reference) {
 }
 
 static void reference_clear_referent(oop reference) {
-  java_lang_ref_Reference::clear_referent(reference);
+  java_lang_ref_Reference::clear_referent_raw(reference);
 }
 
 template <typename T>

diff --git a/src/hotspot/share/gc/z/zReferenceProcessor.cpp b/src/hotspot/share/gc/z/zReferenceProcessor.cpp
@@ -72,7 +72,7 @@ static oop reference_referent(oop reference) {
 }
 
 static void reference_clear_referent(oop reference) {
-  java_lang_ref_Reference::clear_referent(reference);
+  java_lang_ref_Reference::clear_referent_raw(reference);
 }
 
 static oop* reference_discovered_addr(oop reference) {