< prev index next > src/hotspot/share/gc/shenandoah/shenandoahReferenceProcessor.cpp
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*/
#include "precompiled.hpp"
#include "classfile/javaClasses.hpp"
#include "gc/shared/workerThread.hpp"
+ #include "gc/shenandoah/mode/shenandoahGenerationalMode.hpp"
#include "gc/shenandoah/shenandoahOopClosures.inline.hpp"
#include "gc/shenandoah/shenandoahReferenceProcessor.hpp"
#include "gc/shenandoah/shenandoahThreadLocalData.hpp"
#include "gc/shenandoah/shenandoahUtils.hpp"
#include "runtime/atomic.hpp"
template <typename T>
bool ShenandoahReferenceProcessor::should_discover(oop reference, ReferenceType type) const {
T* referent_addr = (T*) java_lang_ref_Reference::referent_addr_raw(reference);
T heap_oop = RawAccess<>::oop_load(referent_addr);
oop referent = CompressedOops::decode(heap_oop);
+ ShenandoahHeap* heap = ShenandoahHeap::heap();
if (is_inactive<T>(reference, referent, type)) {
log_trace(gc,ref)("Reference inactive: " PTR_FORMAT, p2i(reference));
return false;
}
if (is_softly_live(reference, type)) {
log_trace(gc,ref)("Reference softly live: " PTR_FORMAT, p2i(reference));
return false;
}
+ if (!heap->is_in_active_generation(referent)) {
+ log_trace(gc,ref)("Referent outside of active generation: " PTR_FORMAT, p2i(referent));
+ return false;
+ }
+
return true;
}
template <typename T>
bool ShenandoahReferenceProcessor::should_drop(oop reference, ReferenceType type) const {
if (!RegisterReferences) {
// Reference processing disabled
return false;
}
! log_trace(gc, ref)("Encountered Reference: " PTR_FORMAT " (%s)", p2i(reference), reference_type_name(type));
uint worker_id = WorkerThread::worker_id();
_ref_proc_thread_locals->inc_encountered(type);
if (UseCompressedOops) {
return discover<narrowOop>(reference, type, worker_id);
if (!RegisterReferences) {
// Reference processing disabled
return false;
}
! log_trace(gc, ref)("Encountered Reference: " PTR_FORMAT " (%s, %s)",
+ p2i(reference), reference_type_name(type), affiliation_name(reference));
uint worker_id = WorkerThread::worker_id();
_ref_proc_thread_locals->inc_encountered(type);
if (UseCompressedOops) {
return discover<narrowOop>(reference, type, worker_id);
template <typename T>
oop ShenandoahReferenceProcessor::drop(oop reference, ReferenceType type) {
log_trace(gc, ref)("Dropped Reference: " PTR_FORMAT " (%s)", p2i(reference), reference_type_name(type));
! #ifdef ASSERT
oop referent = reference_referent<T>(reference);
! assert(referent == nullptr || ShenandoahHeap::heap()->marking_context()->is_marked(referent),
- "only drop references with alive referents");
- #endif
// Unlink and return next in list
oop next = reference_discovered<T>(reference);
reference_set_discovered<T>(reference, nullptr);
return next;
}
template <typename T>
T* ShenandoahReferenceProcessor::keep(oop reference, ReferenceType type, uint worker_id) {
template <typename T>
oop ShenandoahReferenceProcessor::drop(oop reference, ReferenceType type) {
log_trace(gc, ref)("Dropped Reference: " PTR_FORMAT " (%s)", p2i(reference), reference_type_name(type));
! ShenandoahHeap* heap = ShenandoahHeap::heap();
oop referent = reference_referent<T>(reference);
! assert(referent == nullptr || heap->marking_context()->is_marked(referent), "only drop references with alive referents");
// Unlink and return next in list
oop next = reference_discovered<T>(reference);
reference_set_discovered<T>(reference, nullptr);
+ // When this reference was discovered, it would not have been marked. If it ends up surviving
+ // the cycle, we need to dirty the card if the reference is old and the referent is young. Note
+ // that if the reference is not dropped, then its pointer to the referent will be nulled before
+ // evacuation begins so card does not need to be dirtied.
+ if (heap->mode()->is_generational() && heap->is_in_old(reference) && heap->is_in_young(referent)) {
+ // Note: would be sufficient to mark only the card that holds the start of this Reference object.
+ heap->card_scan()->mark_range_as_dirty(cast_from_oop<HeapWord*>(reference), reference->size());
+ }
return next;
}
template <typename T>
T* ShenandoahReferenceProcessor::keep(oop reference, ReferenceType type, uint worker_id) {
void ShenandoahReferenceProcessor::enqueue_references(bool concurrent) {
if (_pending_list == nullptr) {
// Nothing to enqueue
return;
}
-
if (!concurrent) {
// When called from mark-compact or degen-GC, the locking is done by the VMOperation,
enqueue_references_locked();
} else {
// Heap_lock protects external pending list
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