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#include "gc/shenandoah/shenandoahWorkGroup.hpp"
#include "gc/shenandoah/shenandoahHeapRegionSet.inline.hpp"
#include "gc/shenandoah/shenandoahHeapRegion.inline.hpp"
#include "gc/shenandoah/shenandoahControlThread.hpp"
#include "gc/shenandoah/shenandoahMarkingContext.inline.hpp"
+ #include "gc/shenandoah/shenandoahScanRemembered.inline.hpp"
#include "gc/shenandoah/shenandoahThreadLocalData.hpp"
+ #include "gc/shenandoah/shenandoahScanRemembered.inline.hpp"
+ #include "gc/shenandoah/mode/shenandoahMode.hpp"
#include "oops/compressedOops.inline.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/atomic.hpp"
#include "runtime/prefetch.inline.hpp"
#include "runtime/thread.hpp"
} else {
return true;
}
}
- inline void ShenandoahHeap::clear_cancelled_gc() {
+ inline void ShenandoahHeap::clear_cancelled_gc(bool clear_oom_handler) {
_cancelled_gc.set(CANCELLABLE);
- _oom_evac_handler.clear();
+ if (_cancel_requested_time > 0) {
+ double cancel_time = os::elapsedTime() - _cancel_requested_time;
+ log_info(gc)("GC cancellation took %.3fs", cancel_time);
+ _cancel_requested_time = 0;
+ }
+
+ if (clear_oom_handler) {
+ _oom_evac_handler.clear();
+ }
}
inline HeapWord* ShenandoahHeap::allocate_from_gclab(Thread* thread, size_t size) {
assert(UseTLAB, "TLABs should be enabled");
}
HeapWord* obj = gclab->allocate(size);
if (obj != NULL) {
return obj;
}
- // Otherwise...
return allocate_from_gclab_slow(thread, size);
}
+ inline HeapWord* ShenandoahHeap::allocate_from_plab(Thread* thread, size_t size, bool is_promotion) {
+ assert(UseTLAB, "TLABs should be enabled");
+
+ PLAB* plab = ShenandoahThreadLocalData::plab(thread);
+ if (is_promotion && !ShenandoahThreadLocalData::allow_plab_promotions(thread)) {
+ return NULL;
+ } else if (plab == NULL) {
+ assert(!thread->is_Java_thread() && !thread->is_Worker_thread(),
+ "Performance: thread should have PLAB: %s", thread->name());
+ // No PLABs in this thread, fallback to shared allocation
+ return NULL;
+ }
+ HeapWord* obj = plab->allocate(size);
+ if (obj == NULL) {
+ obj = allocate_from_plab_slow(thread, size, is_promotion);
+ }
+ if (is_promotion) {
+ ShenandoahThreadLocalData::add_to_plab_promoted(thread, size * HeapWordSize);
+ } else {
+ ShenandoahThreadLocalData::add_to_plab_evacuated(thread, size * HeapWordSize);
+ }
+ return obj;
+ }
+
inline oop ShenandoahHeap::evacuate_object(oop p, Thread* thread) {
- if (ShenandoahThreadLocalData::is_oom_during_evac(Thread::current())) {
+ assert(thread == Thread::current(), "Expected thread parameter to be current thread.");
+ if (ShenandoahThreadLocalData::is_oom_during_evac(thread)) {
// This thread went through the OOM during evac protocol and it is safe to return
// the forward pointer. It must not attempt to evacuate any more.
return ShenandoahBarrierSet::resolve_forwarded(p);
}
assert(ShenandoahThreadLocalData::is_evac_allowed(thread), "must be enclosed in oom-evac scope");
- size_t size = p->size();
+ ShenandoahHeapRegion* r = heap_region_containing(p);
+ assert(!r->is_humongous(), "never evacuate humongous objects");
- assert(!heap_region_containing(p)->is_humongous(), "never evacuate humongous objects");
+ ShenandoahRegionAffiliation target_gen = r->affiliation();
+ if (mode()->is_generational() && ShenandoahHeap::heap()->is_gc_generation_young() &&
+ target_gen == YOUNG_GENERATION && ShenandoahPromoteTenuredObjects) {
+ markWord mark = p->mark();
+ if (mark.is_marked()) {
+ // Already forwarded.
+ return ShenandoahBarrierSet::resolve_forwarded(p);
+ }
+ if (mark.has_displaced_mark_helper()) {
+ // We don't want to deal with MT here just to ensure we read the right mark word.
+ // Skip the potential promotion attempt for this one.
+ } else if (r->age() + mark.age() >= InitialTenuringThreshold) {
+ oop result = try_evacuate_object(p, thread, r, OLD_GENERATION);
+ if (result != NULL) {
+ return result;
+ }
+ // If we failed to promote this aged object, we'll fall through to code below and evacuat to young-gen.
+ }
+ }
+ return try_evacuate_object(p, thread, r, target_gen);
+ }
- bool alloc_from_gclab = true;
+ // try_evacuate_object registers the object and dirties the associated remembered set information when evacuating
+ // to OLD_GENERATION.
+ inline oop ShenandoahHeap::try_evacuate_object(oop p, Thread* thread, ShenandoahHeapRegion* from_region,
+ ShenandoahRegionAffiliation target_gen) {
+ bool alloc_from_lab = true;
HeapWord* copy = NULL;
+ size_t size = p->size();
+ bool is_promotion = (target_gen == OLD_GENERATION) && from_region->is_young();
#ifdef ASSERT
if (ShenandoahOOMDuringEvacALot &&
(os::random() & 1) == 0) { // Simulate OOM every ~2nd slow-path call
copy = NULL;
} else {
#endif
if (UseTLAB) {
- copy = allocate_from_gclab(thread, size);
+ switch (target_gen) {
+ case YOUNG_GENERATION: {
+ copy = allocate_from_gclab(thread, size);
+ if ((copy == nullptr) && (size < ShenandoahThreadLocalData::gclab_size(thread))) {
+ // GCLAB allocation failed because we are bumping up against the limit on young evacuation reserve. Try resetting
+ // the desired GCLAB size and retry GCLAB allocation to avoid cascading of shared memory allocations.
+ ShenandoahThreadLocalData::set_gclab_size(thread, PLAB::min_size());
+ copy = allocate_from_gclab(thread, size);
+ // If we still get nullptr, we'll try a shared allocation below.
+ }
+ break;
+ }
+ case OLD_GENERATION: {
+ if (ShenandoahUsePLAB) {
+ copy = allocate_from_plab(thread, size, is_promotion);
+ if ((copy == nullptr) && (size < ShenandoahThreadLocalData::plab_size(thread))) {
+ // PLAB allocation failed because we are bumping up against the limit on old evacuation reserve. Try resetting
+ // the desired PLAB size and retry PLAB allocation to avoid cascading of shared memory allocations.
+ ShenandoahThreadLocalData::set_plab_size(thread, PLAB::min_size());
+ copy = allocate_from_plab(thread, size, is_promotion);
+ // If we still get nullptr, we'll try a shared allocation below.
+ }
+ }
+ break;
+ }
+ default: {
+ ShouldNotReachHere();
+ break;
+ }
+ }
}
+
if (copy == NULL) {
- ShenandoahAllocRequest req = ShenandoahAllocRequest::for_shared_gc(size);
- copy = allocate_memory(req);
- alloc_from_gclab = false;
+ // If we failed to allocated in LAB, we'll try a shared allocation.
+ ShenandoahAllocRequest req = ShenandoahAllocRequest::for_shared_gc(size, target_gen);
+ copy = allocate_memory(req, is_promotion);
+ alloc_from_lab = false;
}
#ifdef ASSERT
}
#endif
if (copy == NULL) {
+ if (target_gen == OLD_GENERATION) {
+ assert(mode()->is_generational(), "Should only be here in generational mode.");
+ if (from_region->is_young()) {
+ // Signal that promotion failed. Will evacuate this old object somewhere in young gen.
+ handle_promotion_failure();
+ return NULL;
+ } else {
+ // Remember that evacuation to old gen failed. We'll want to trigger a full gc to recover from this
+ // after the evacuation threads have finished.
+ handle_old_evacuation_failure();
+ }
+ }
+
control_thread()->handle_alloc_failure_evac(size);
_oom_evac_handler.handle_out_of_memory_during_evacuation();
return ShenandoahBarrierSet::resolve_forwarded(p);
}
// Copy the object:
Copy::aligned_disjoint_words(cast_from_oop<HeapWord*>(p), copy, size);
- // Try to install the new forwarding pointer.
oop copy_val = cast_to_oop(copy);
+
+ if (mode()->is_generational() && target_gen == YOUNG_GENERATION && is_aging_cycle()) {
+ ShenandoahHeap::increase_object_age(copy_val, from_region->age() + 1);
+ }
+
+ // Try to install the new forwarding pointer.
oop result = ShenandoahForwarding::try_update_forwardee(p, copy_val);
if (result == copy_val) {
// Successfully evacuated. Our copy is now the public one!
+ if (mode()->is_generational() && target_gen == OLD_GENERATION) {
+ handle_old_evacuation(copy, size, from_region->is_young());
+ }
shenandoah_assert_correct(NULL, copy_val);
return copy_val;
} else {
// Failed to evacuate. We need to deal with the object that is left behind. Since this
// new allocation is certainly after TAMS, it will be considered live in the next cycle.
// But if it happens to contain references to evacuated regions, those references would
// not get updated for this stale copy during this cycle, and we will crash while scanning
// it the next cycle.
- //
- // For GCLAB allocations, it is enough to rollback the allocation ptr. Either the next
- // object will overwrite this stale copy, or the filler object on LAB retirement will
- // do this. For non-GCLAB allocations, we have no way to retract the allocation, and
- // have to explicitly overwrite the copy with the filler object. With that overwrite,
- // we have to keep the fwdptr initialized and pointing to our (stale) copy.
- if (alloc_from_gclab) {
- ShenandoahThreadLocalData::gclab(thread)->undo_allocation(copy, size);
+ if (alloc_from_lab) {
+ // For LAB allocations, it is enough to rollback the allocation ptr. Either the next
+ // object will overwrite this stale copy, or the filler object on LAB retirement will
+ // do this.
+ switch (target_gen) {
+ case YOUNG_GENERATION: {
+ ShenandoahThreadLocalData::gclab(thread)->undo_allocation(copy, size);
+ break;
+ }
+ case OLD_GENERATION: {
+ ShenandoahThreadLocalData::plab(thread)->undo_allocation(copy, size);
+ if (is_promotion) {
+ ShenandoahThreadLocalData::subtract_from_plab_promoted(thread, size * HeapWordSize);
+ } else {
+ ShenandoahThreadLocalData::subtract_from_plab_evacuated(thread, size * HeapWordSize);
+ }
+ break;
+ }
+ default: {
+ ShouldNotReachHere();
+ break;
+ }
+ }
} else {
+ // For non-LAB allocations, we have no way to retract the allocation, and
+ // have to explicitly overwrite the copy with the filler object. With that overwrite,
+ // we have to keep the fwdptr initialized and pointing to our (stale) copy.
fill_with_object(copy, size);
shenandoah_assert_correct(NULL, copy_val);
+ // For non-LAB allocations, the object has already been registered
}
shenandoah_assert_correct(NULL, result);
return result;
}
}
+ void ShenandoahHeap::increase_object_age(oop obj, uint additional_age) {
+ markWord w = obj->has_displaced_mark() ? obj->displaced_mark() : obj->mark();
+ w = w.set_age(MIN2(markWord::max_age, w.age() + additional_age));
+ if (obj->has_displaced_mark()) {
+ obj->set_displaced_mark(w);
+ } else {
+ obj->set_mark(w);
+ }
+ }
+
+ inline bool ShenandoahHeap::clear_old_evacuation_failure() {
+ return _old_gen_oom_evac.try_unset();
+ }
+
+ inline bool ShenandoahHeap::is_old(oop obj) const {
+ return is_gc_generation_young() && is_in_old(obj);
+ }
+
inline bool ShenandoahHeap::requires_marking(const void* entry) const {
oop obj = cast_to_oop(entry);
return !_marking_context->is_marked_strong(obj);
}
inline bool ShenandoahHeap::is_stable() const {
return _gc_state.is_clear();
}
inline bool ShenandoahHeap::is_idle() const {
- return _gc_state.is_unset(MARKING | EVACUATION | UPDATEREFS);
+ return _gc_state.is_unset(YOUNG_MARKING | OLD_MARKING | EVACUATION | UPDATEREFS);
}
inline bool ShenandoahHeap::is_concurrent_mark_in_progress() const {
- return _gc_state.is_set(MARKING);
+ return _gc_state.is_set(YOUNG_MARKING | OLD_MARKING);
+ }
+
+ inline bool ShenandoahHeap::is_concurrent_young_mark_in_progress() const {
+ return _gc_state.is_set(YOUNG_MARKING);
+ }
+
+ inline bool ShenandoahHeap::is_concurrent_old_mark_in_progress() const {
+ return _gc_state.is_set(OLD_MARKING);
}
inline bool ShenandoahHeap::is_evacuation_in_progress() const {
return _gc_state.is_set(EVACUATION);
}
inline bool ShenandoahHeap::is_concurrent_weak_root_in_progress() const {
return _gc_state.is_set(WEAK_ROOTS);
}
+ inline bool ShenandoahHeap::is_aging_cycle() const {
+ return _is_aging_cycle.is_set();
+ }
+
+ inline size_t ShenandoahHeap::set_promotion_reserve(size_t new_val) {
+ size_t orig = _promotion_reserve;
+ _promotion_reserve = new_val;
+ return orig;
+ }
+
+ inline size_t ShenandoahHeap::get_promotion_reserve() const {
+ return _promotion_reserve;
+ }
+
+ // returns previous value
+ size_t ShenandoahHeap::capture_old_usage(size_t old_usage) {
+ size_t previous_value = _captured_old_usage;
+ _captured_old_usage = old_usage;
+ return previous_value;
+ }
+
+ void ShenandoahHeap::set_previous_promotion(size_t promoted_bytes) {
+ _previous_promotion = promoted_bytes;
+ }
+
+ size_t ShenandoahHeap::get_previous_promotion() const {
+ return _previous_promotion;
+ }
+
+ inline size_t ShenandoahHeap::set_old_evac_reserve(size_t new_val) {
+ size_t orig = _old_evac_reserve;
+ _old_evac_reserve = new_val;
+ return orig;
+ }
+
+ inline size_t ShenandoahHeap::get_old_evac_reserve() const {
+ return _old_evac_reserve;
+ }
+
+ inline void ShenandoahHeap::reset_old_evac_expended() {
+ _old_evac_expended = 0;
+ }
+
+ inline size_t ShenandoahHeap::expend_old_evac(size_t increment) {
+ _old_evac_expended += increment;
+ return _old_evac_expended;
+ }
+
+ inline size_t ShenandoahHeap::get_old_evac_expended() const {
+ return _old_evac_expended;
+ }
+
+ inline size_t ShenandoahHeap::set_young_evac_reserve(size_t new_val) {
+ size_t orig = _young_evac_reserve;
+ _young_evac_reserve = new_val;
+ return orig;
+ }
+
+ inline size_t ShenandoahHeap::get_young_evac_reserve() const {
+ return _young_evac_reserve;
+ }
+
+ inline intptr_t ShenandoahHeap::set_alloc_supplement_reserve(intptr_t new_val) {
+ intptr_t orig = _alloc_supplement_reserve;
+ _alloc_supplement_reserve = new_val;
+ return orig;
+ }
+
+ inline intptr_t ShenandoahHeap::get_alloc_supplement_reserve() const {
+ return _alloc_supplement_reserve;
+ }
+
template<class T>
inline void ShenandoahHeap::marked_object_iterate(ShenandoahHeapRegion* region, T* cl) {
marked_object_iterate(region, cl, region->top());
}
template<class T>
inline void ShenandoahHeap::marked_object_iterate(ShenandoahHeapRegion* region, T* cl, HeapWord* limit) {
assert(! region->is_humongous_continuation(), "no humongous continuation regions here");
- ShenandoahMarkingContext* const ctx = complete_marking_context();
- assert(ctx->is_complete(), "sanity");
+ ShenandoahMarkingContext* const ctx = marking_context();
HeapWord* tams = ctx->top_at_mark_start(region);
size_t skip_bitmap_delta = 1;
HeapWord* start = region->bottom();
} else {
return NULL;
}
}
- inline void ShenandoahHeap::mark_complete_marking_context() {
- _marking_context->mark_complete();
- }
-
- inline void ShenandoahHeap::mark_incomplete_marking_context() {
- _marking_context->mark_incomplete();
- }
-
inline ShenandoahMarkingContext* ShenandoahHeap::complete_marking_context() const {
assert (_marking_context->is_complete()," sanity");
return _marking_context;
}
inline ShenandoahMarkingContext* ShenandoahHeap::marking_context() const {
return _marking_context;
}
+ inline void ShenandoahHeap::clear_cards_for(ShenandoahHeapRegion* region) {
+ if (mode()->is_generational()) {
+ _card_scan->mark_range_as_empty(region->bottom(), pointer_delta(region->end(), region->bottom()));
+ }
+ }
+
+ inline void ShenandoahHeap::dirty_cards(HeapWord* start, HeapWord* end) {
+ assert(mode()->is_generational(), "Should only be used for generational mode");
+ size_t words = pointer_delta(end, start);
+ _card_scan->mark_range_as_dirty(start, words);
+ }
+
+ inline void ShenandoahHeap::clear_cards(HeapWord* start, HeapWord* end) {
+ assert(mode()->is_generational(), "Should only be used for generational mode");
+ size_t words = pointer_delta(end, start);
+ _card_scan->mark_range_as_clean(start, words);
+ }
+
+ inline void ShenandoahHeap::mark_card_as_dirty(void* location) {
+ if (mode()->is_generational()) {
+ _card_scan->mark_card_as_dirty((HeapWord*)location);
+ }
+ }
+
#endif // SHARE_GC_SHENANDOAH_SHENANDOAHHEAP_INLINE_HPP
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