jdk-sandbox: comparison src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp

equal deleted inserted replaced

-:420ff459906f
+:9c18c9d839d3
+/*
+* Copyright (c) 2013, 2018, Red Hat, Inc. All rights reserved.
+*
+* This code is free software; you can redistribute it and/or modify it
+* under the terms of the GNU General Public License version 2 only, as
+* published by the Free Software Foundation.
+*
+* This code is distributed in the hope that it will be useful, but WITHOUT
+* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+* version 2 for more details (a copy is included in the LICENSE file that
+* accompanied this code).
+*
+* You should have received a copy of the GNU General Public License version
+* 2 along with this work; if not, write to the Free Software Foundation,
+* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+*
+* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+* or visit www.oracle.com if you need additional information or have any
+* questions.
+*
+*/
+#include "precompiled.hpp"
+#include "memory/allocation.hpp"
+#include "gc/shared/gcTimer.hpp"
+#include "gc/shared/gcTraceTime.inline.hpp"
+#include "gc/shared/memAllocator.hpp"
+#include "gc/shared/parallelCleaning.hpp"
+#include "gc/shared/plab.hpp"
+#include "gc/shenandoah/shenandoahAllocTracker.hpp"
+#include "gc/shenandoah/shenandoahBarrierSet.hpp"
+#include "gc/shenandoah/shenandoahBrooksPointer.hpp"
+#include "gc/shenandoah/shenandoahCollectionSet.hpp"
+#include "gc/shenandoah/shenandoahCollectorPolicy.hpp"
+#include "gc/shenandoah/shenandoahConcurrentMark.hpp"
+#include "gc/shenandoah/shenandoahConcurrentMark.inline.hpp"
+#include "gc/shenandoah/shenandoahControlThread.hpp"
+#include "gc/shenandoah/shenandoahFreeSet.hpp"
+#include "gc/shenandoah/shenandoahPhaseTimings.hpp"
+#include "gc/shenandoah/shenandoahHeap.inline.hpp"
+#include "gc/shenandoah/shenandoahHeapRegion.hpp"
+#include "gc/shenandoah/shenandoahHeapRegionSet.hpp"
+#include "gc/shenandoah/shenandoahMarkCompact.hpp"
+#include "gc/shenandoah/shenandoahMarkingContext.inline.hpp"
+#include "gc/shenandoah/shenandoahMemoryPool.hpp"
+#include "gc/shenandoah/shenandoahMetrics.hpp"
+#include "gc/shenandoah/shenandoahMonitoringSupport.hpp"
+#include "gc/shenandoah/shenandoahOopClosures.inline.hpp"
+#include "gc/shenandoah/shenandoahPacer.hpp"
+#include "gc/shenandoah/shenandoahPacer.inline.hpp"
+#include "gc/shenandoah/shenandoahRootProcessor.hpp"
+#include "gc/shenandoah/shenandoahStringDedup.hpp"
+#include "gc/shenandoah/shenandoahUtils.hpp"
+#include "gc/shenandoah/shenandoahVerifier.hpp"
+#include "gc/shenandoah/shenandoahCodeRoots.hpp"
+#include "gc/shenandoah/shenandoahVMOperations.hpp"
+#include "gc/shenandoah/shenandoahWorkGroup.hpp"
+#include "gc/shenandoah/shenandoahWorkerPolicy.hpp"
+#include "gc/shenandoah/heuristics/shenandoahAdaptiveHeuristics.hpp"
+#include "gc/shenandoah/heuristics/shenandoahAggressiveHeuristics.hpp"
+#include "gc/shenandoah/heuristics/shenandoahCompactHeuristics.hpp"
+#include "gc/shenandoah/heuristics/shenandoahPassiveHeuristics.hpp"
+#include "gc/shenandoah/heuristics/shenandoahStaticHeuristics.hpp"
+#include "gc/shenandoah/heuristics/shenandoahTraversalHeuristics.hpp"
+#include "memory/metaspace.hpp"
+#include "runtime/vmThread.hpp"
+#include "services/mallocTracker.hpp"
+ShenandoahUpdateRefsClosure::ShenandoahUpdateRefsClosure() : _heap(ShenandoahHeap::heap()) {}
+#ifdef ASSERT
+template <class T>
+void ShenandoahAssertToSpaceClosure::do_oop_work(T* p) {
+T o = RawAccess<>::oop_load(p);
+if (! CompressedOops::is_null(o)) {
+oop obj = CompressedOops::decode_not_null(o);
+shenandoah_assert_not_forwarded(p, obj);
+}
+}
+void ShenandoahAssertToSpaceClosure::do_oop(narrowOop* p) { do_oop_work(p); }
+void ShenandoahAssertToSpaceClosure::do_oop(oop* p)       { do_oop_work(p); }
+#endif
+class ShenandoahPretouchTask : public AbstractGangTask {
+private:
+ShenandoahRegionIterator _regions;
+const size_t _bitmap_size;
+const size_t _page_size;
+char* _bitmap_base;
+public:
+ShenandoahPretouchTask(char* bitmap_base, size_t bitmap_size, size_t page_size) :
+AbstractGangTask("Shenandoah PreTouch"),
+_bitmap_size(bitmap_size),
+_page_size(page_size),
+_bitmap_base(bitmap_base) {
+}
+virtual void work(uint worker_id) {
+ShenandoahHeapRegion* r = _regions.next();
+while (r != NULL) {
+os::pretouch_memory(r->bottom(), r->end(), _page_size);
+size_t start = r->region_number()       * ShenandoahHeapRegion::region_size_bytes() / MarkBitMap::heap_map_factor();
+size_t end   = (r->region_number() + 1) * ShenandoahHeapRegion::region_size_bytes() / MarkBitMap::heap_map_factor();
+assert (end <= _bitmap_size, "end is sane: " SIZE_FORMAT " < " SIZE_FORMAT, end, _bitmap_size);
+os::pretouch_memory(_bitmap_base + start, _bitmap_base + end, _page_size);
+r = _regions.next();
+}
+}
+};
+jint ShenandoahHeap::initialize() {
+ShenandoahBrooksPointer::initial_checks();
+initialize_heuristics();
+size_t init_byte_size = collector_policy()->initial_heap_byte_size();
+size_t max_byte_size = collector_policy()->max_heap_byte_size();
+size_t heap_alignment = collector_policy()->heap_alignment();
+if (ShenandoahAlwaysPreTouch) {
+// Enabled pre-touch means the entire heap is committed right away.
+init_byte_size = max_byte_size;
+}
+Universe::check_alignment(max_byte_size,
+ShenandoahHeapRegion::region_size_bytes(),
+"shenandoah heap");
+Universe::check_alignment(init_byte_size,
+ShenandoahHeapRegion::region_size_bytes(),
+"shenandoah heap");
+ReservedSpace heap_rs = Universe::reserve_heap(max_byte_size,
+heap_alignment);
+initialize_reserved_region((HeapWord*)heap_rs.base(), (HeapWord*) (heap_rs.base() + heap_rs.size()));
+ReservedSpace pgc_rs = heap_rs.first_part(max_byte_size);
+_num_regions = ShenandoahHeapRegion::region_count();
+size_t num_committed_regions = init_byte_size / ShenandoahHeapRegion::region_size_bytes();
+num_committed_regions = MIN2(num_committed_regions, _num_regions);
+assert(num_committed_regions <= _num_regions, "sanity");
+_initial_size = num_committed_regions * ShenandoahHeapRegion::region_size_bytes();
+_committed = _initial_size;
+log_info(gc, heap)("Initialize Shenandoah heap with initial size " SIZE_FORMAT "%s",
+byte_size_in_proper_unit(_initial_size), proper_unit_for_byte_size(_initial_size));
+if (!os::commit_memory(pgc_rs.base(), _initial_size, false)) {
+vm_exit_out_of_memory(_initial_size, OOM_MMAP_ERROR, "Shenandoah failed to initialize heap");
+}
+size_t reg_size_words = ShenandoahHeapRegion::region_size_words();
+size_t reg_size_bytes = ShenandoahHeapRegion::region_size_bytes();
+_regions = NEW_C_HEAP_ARRAY(ShenandoahHeapRegion*, _num_regions, mtGC);
+_free_set = new ShenandoahFreeSet(this, _num_regions);
+_collection_set = new ShenandoahCollectionSet(this, (HeapWord*)pgc_rs.base());
+if (ShenandoahPacing) {
+_pacer = new ShenandoahPacer(this);
+_pacer->setup_for_idle();
+} else {
+_pacer = NULL;
+}
+assert((((size_t) base()) & ShenandoahHeapRegion::region_size_bytes_mask()) == 0,
+"misaligned heap: " PTR_FORMAT, p2i(base()));
+// The call below uses stuff (the SATB* things) that are in G1, but probably
+// belong into a shared location.
+ShenandoahBarrierSet::satb_mark_queue_set().initialize(this,
+SATB_Q_CBL_mon,
+20 /*G1SATBProcessCompletedThreshold */,
+60 /* G1SATBBufferEnqueueingThresholdPercent */,
+Shared_SATB_Q_lock);
+// Reserve space for prev and next bitmap.
+size_t bitmap_page_size = UseLargePages ? (size_t)os::large_page_size() : (size_t)os::vm_page_size();
+_bitmap_size = MarkBitMap::compute_size(heap_rs.size());
+_bitmap_size = align_up(_bitmap_size, bitmap_page_size);
+_heap_region = MemRegion((HeapWord*) heap_rs.base(), heap_rs.size() / HeapWordSize);
+size_t bitmap_bytes_per_region = reg_size_bytes / MarkBitMap::heap_map_factor();
+guarantee(bitmap_bytes_per_region != 0,
+"Bitmap bytes per region should not be zero");
+guarantee(is_power_of_2(bitmap_bytes_per_region),
+"Bitmap bytes per region should be power of two: " SIZE_FORMAT, bitmap_bytes_per_region);
+if (bitmap_page_size > bitmap_bytes_per_region) {
+_bitmap_regions_per_slice = bitmap_page_size / bitmap_bytes_per_region;
+_bitmap_bytes_per_slice = bitmap_page_size;
+} else {
+_bitmap_regions_per_slice = 1;
+_bitmap_bytes_per_slice = bitmap_bytes_per_region;
+}
+guarantee(_bitmap_regions_per_slice >= 1,
+"Should have at least one region per slice: " SIZE_FORMAT,
+_bitmap_regions_per_slice);
+guarantee(((_bitmap_bytes_per_slice) % bitmap_page_size) == 0,
+"Bitmap slices should be page-granular: bps = " SIZE_FORMAT ", page size = " SIZE_FORMAT,
+_bitmap_bytes_per_slice, bitmap_page_size);
+ReservedSpace bitmap0(_bitmap_size, bitmap_page_size);
+MemTracker::record_virtual_memory_type(bitmap0.base(), mtGC);
+_bitmap_region = MemRegion((HeapWord*) bitmap0.base(), bitmap0.size() / HeapWordSize);
+size_t bitmap_init_commit = _bitmap_bytes_per_slice *
+align_up(num_committed_regions, _bitmap_regions_per_slice) / _bitmap_regions_per_slice;
+bitmap_init_commit = MIN2(_bitmap_size, bitmap_init_commit);
+os::commit_memory_or_exit((char *) (_bitmap_region.start()), bitmap_init_commit, false,
+"couldn't allocate initial bitmap");
+size_t page_size = UseLargePages ? (size_t)os::large_page_size() : (size_t)os::vm_page_size();
+if (ShenandoahVerify) {
+ReservedSpace verify_bitmap(_bitmap_size, page_size);
+os::commit_memory_or_exit(verify_bitmap.base(), verify_bitmap.size(), false,
+"couldn't allocate verification bitmap");
+MemTracker::record_virtual_memory_type(verify_bitmap.base(), mtGC);
+MemRegion verify_bitmap_region = MemRegion((HeapWord *) verify_bitmap.base(), verify_bitmap.size() / HeapWordSize);
+_verification_bit_map.initialize(_heap_region, verify_bitmap_region);
+_verifier = new ShenandoahVerifier(this, &_verification_bit_map);
+}
+_marking_context = new ShenandoahMarkingContext(_heap_region, _bitmap_region, _num_regions);
+{
+ShenandoahHeapLocker locker(lock());
+for (size_t i = 0; i < _num_regions; i++) {
+ShenandoahHeapRegion* r = new ShenandoahHeapRegion(this,
+(HeapWord*) pgc_rs.base() + reg_size_words * i,
+reg_size_words,
+i,
+i < num_committed_regions);
+_marking_context->initialize_top_at_mark_start(r);
+_regions[i] = r;
+assert(!collection_set()->is_in(i), "New region should not be in collection set");
+}
+// Initialize to complete
+_marking_context->mark_complete();
+_free_set->rebuild();
+}
+if (ShenandoahAlwaysPreTouch) {
+assert (!AlwaysPreTouch, "Should have been overridden");
+// For NUMA, it is important to pre-touch the storage under bitmaps with worker threads,
+// before initialize() below zeroes it with initializing thread. For any given region,
+// we touch the region and the corresponding bitmaps from the same thread.
+ShenandoahPushWorkerScope scope(workers(), _max_workers, false);
+log_info(gc, heap)("Parallel pretouch " SIZE_FORMAT " regions with " SIZE_FORMAT " byte pages",
+_num_regions, page_size);
+ShenandoahPretouchTask cl(bitmap0.base(), _bitmap_size, page_size);
+_workers->run_task(&cl);
+}
+// Reserve aux bitmap for use in object_iterate(). We don't commit it here.
+ReservedSpace aux_bitmap(_bitmap_size, bitmap_page_size);
+MemTracker::record_virtual_memory_type(aux_bitmap.base(), mtGC);
+_aux_bitmap_region = MemRegion((HeapWord*) aux_bitmap.base(), aux_bitmap.size() / HeapWordSize);
+_aux_bit_map.initialize(_heap_region, _aux_bitmap_region);
+_traversal_gc = heuristics()->can_do_traversal_gc() ?
+new ShenandoahTraversalGC(this, _num_regions) :
+NULL;
+_monitoring_support = new ShenandoahMonitoringSupport(this);
+_phase_timings = new ShenandoahPhaseTimings();
+if (ShenandoahAllocationTrace) {
+_alloc_tracker = new ShenandoahAllocTracker();
+}
+ShenandoahStringDedup::initialize();
+_control_thread = new ShenandoahControlThread();
+ShenandoahCodeRoots::initialize();
+log_info(gc, init)("Safepointing mechanism: %s",
+SafepointMechanism::uses_thread_local_poll() ? "thread-local poll" :
+(SafepointMechanism::uses_global_page_poll() ? "global-page poll" : "unknown"));
+_liveness_cache = NEW_C_HEAP_ARRAY(jushort*, _max_workers, mtGC);
+for (uint worker = 0; worker < _max_workers; worker++) {
+_liveness_cache[worker] = NEW_C_HEAP_ARRAY(jushort, _num_regions, mtGC);
+Copy::fill_to_bytes(_liveness_cache[worker], _num_regions * sizeof(jushort));
+}
+return JNI_OK;
+}
+void ShenandoahHeap::initialize_heuristics() {
+if (ShenandoahGCHeuristics != NULL) {
+if (strcmp(ShenandoahGCHeuristics, "aggressive") == 0) {
+_heuristics = new ShenandoahAggressiveHeuristics();
+} else if (strcmp(ShenandoahGCHeuristics, "static") == 0) {
+_heuristics = new ShenandoahStaticHeuristics();
+} else if (strcmp(ShenandoahGCHeuristics, "adaptive") == 0) {
+_heuristics = new ShenandoahAdaptiveHeuristics();
+} else if (strcmp(ShenandoahGCHeuristics, "passive") == 0) {
+_heuristics = new ShenandoahPassiveHeuristics();
+} else if (strcmp(ShenandoahGCHeuristics, "compact") == 0) {
+_heuristics = new ShenandoahCompactHeuristics();
+} else if (strcmp(ShenandoahGCHeuristics, "traversal") == 0) {
+_heuristics = new ShenandoahTraversalHeuristics();
+} else {
+vm_exit_during_initialization("Unknown -XX:ShenandoahGCHeuristics option");
+}
+if (_heuristics->is_diagnostic() && !UnlockDiagnosticVMOptions) {
+vm_exit_during_initialization(
+err_msg("Heuristics \"%s\" is diagnostic, and must be enabled via -XX:+UnlockDiagnosticVMOptions.",
+_heuristics->name()));
+}
+if (_heuristics->is_experimental() && !UnlockExperimentalVMOptions) {
+vm_exit_during_initialization(
+err_msg("Heuristics \"%s\" is experimental, and must be enabled via -XX:+UnlockExperimentalVMOptions.",
+_heuristics->name()));
+}
+if (ShenandoahStoreValEnqueueBarrier && ShenandoahStoreValReadBarrier) {
+vm_exit_during_initialization("Cannot use both ShenandoahStoreValEnqueueBarrier and ShenandoahStoreValReadBarrier");
+}
+log_info(gc, init)("Shenandoah heuristics: %s",
+_heuristics->name());
+} else {
+ShouldNotReachHere();
+}
+}
+#ifdef _MSC_VER
+#pragma warning( push )
+#pragma warning( disable:4355 ) // 'this' : used in base member initializer list
+#endif
+ShenandoahHeap::ShenandoahHeap(ShenandoahCollectorPolicy* policy) :
+CollectedHeap(),
+_initial_size(0),
+_used(0),
+_committed(0),
+_bytes_allocated_since_gc_start(0),
+_max_workers(MAX2(ConcGCThreads, ParallelGCThreads)),
+_workers(NULL),
+_safepoint_workers(NULL),
+_num_regions(0),
+_regions(NULL),
+_update_refs_iterator(this),
+_control_thread(NULL),
+_shenandoah_policy(policy),
+_heuristics(NULL),
+_free_set(NULL),
+_scm(new ShenandoahConcurrentMark()),
+_traversal_gc(NULL),
+_full_gc(new ShenandoahMarkCompact()),
+_pacer(NULL),
+_verifier(NULL),
+_alloc_tracker(NULL),
+_phase_timings(NULL),
+_monitoring_support(NULL),
+_memory_pool(NULL),
+_stw_memory_manager("Shenandoah Pauses", "end of GC pause"),
+_cycle_memory_manager("Shenandoah Cycles", "end of GC cycle"),
+_gc_timer(new (ResourceObj::C_HEAP, mtGC) ConcurrentGCTimer()),
+_soft_ref_policy(),
+_ref_processor(NULL),
+_marking_context(NULL),
+_collection_set(NULL)
+{
+log_info(gc, init)("GC threads: " UINT32_FORMAT " parallel, " UINT32_FORMAT " concurrent", ParallelGCThreads, ConcGCThreads);
+log_info(gc, init)("Reference processing: %s", ParallelRefProcEnabled ? "parallel" : "serial");
+BarrierSet::set_barrier_set(new ShenandoahBarrierSet(this));
+_max_workers = MAX2(_max_workers, 1U);
+_workers = new ShenandoahWorkGang("Shenandoah GC Threads", _max_workers,
+/* are_GC_task_threads */true,
+/* are_ConcurrentGC_threads */false);
+if (_workers == NULL) {
+vm_exit_during_initialization("Failed necessary allocation.");
+} else {
+_workers->initialize_workers();
+}
+if (ShenandoahParallelSafepointThreads > 1) {
+_safepoint_workers = new ShenandoahWorkGang("Safepoint Cleanup Thread",
+ShenandoahParallelSafepointThreads,
+false, false);
+_safepoint_workers->initialize_workers();
+}
+}
+#ifdef _MSC_VER
+#pragma warning( pop )
+#endif
+class ShenandoahResetBitmapTask : public AbstractGangTask {
+private:
+ShenandoahRegionIterator _regions;
+public:
+ShenandoahResetBitmapTask() :
+AbstractGangTask("Parallel Reset Bitmap Task") {}
+void work(uint worker_id) {
+ShenandoahHeapRegion* region = _regions.next();
+ShenandoahHeap* heap = ShenandoahHeap::heap();
+ShenandoahMarkingContext* const ctx = heap->marking_context();
+while (region != NULL) {
+if (heap->is_bitmap_slice_committed(region)) {
+ctx->clear_bitmap(region);
+}
+region = _regions.next();
+}
+}
+};
+void ShenandoahHeap::reset_mark_bitmap() {
+assert_gc_workers(_workers->active_workers());
+mark_incomplete_marking_context();
+ShenandoahResetBitmapTask task;
+_workers->run_task(&task);
+}
+void ShenandoahHeap::print_on(outputStream* st) const {
+st->print_cr("Shenandoah Heap");
+st->print_cr(" " SIZE_FORMAT "K total, " SIZE_FORMAT "K committed, " SIZE_FORMAT "K used",
+capacity() / K, committed() / K, used() / K);
+st->print_cr(" " SIZE_FORMAT " x " SIZE_FORMAT"K regions",
+num_regions(), ShenandoahHeapRegion::region_size_bytes() / K);
+st->print("Status: ");
+if (has_forwarded_objects())               st->print("has forwarded objects, ");
+if (is_concurrent_mark_in_progress())      st->print("marking, ");
+if (is_evacuation_in_progress())           st->print("evacuating, ");
+if (is_update_refs_in_progress())          st->print("updating refs, ");
+if (is_concurrent_traversal_in_progress()) st->print("traversal, ");
+if (is_degenerated_gc_in_progress())       st->print("degenerated gc, ");
+if (is_full_gc_in_progress())              st->print("full gc, ");
+if (is_full_gc_move_in_progress())         st->print("full gc move, ");
+if (cancelled_gc()) {
+st->print("cancelled");
+} else {
+st->print("not cancelled");
+}
+st->cr();
+st->print_cr("Reserved region:");
+st->print_cr(" - [" PTR_FORMAT ", " PTR_FORMAT ") ",
+p2i(reserved_region().start()),
+p2i(reserved_region().end()));
+st->cr();
+MetaspaceUtils::print_on(st);
+if (Verbose) {
+print_heap_regions_on(st);
+}
+}
+class ShenandoahInitGCLABClosure : public ThreadClosure {
+public:
+void do_thread(Thread* thread) {
+if (thread != NULL && (thread->is_Java_thread() || thread->is_Worker_thread())) {
+ShenandoahThreadLocalData::initialize_gclab(thread);
+}
+}
+};
+void ShenandoahHeap::post_initialize() {
+CollectedHeap::post_initialize();
+MutexLocker ml(Threads_lock);
+ShenandoahInitGCLABClosure init_gclabs;
+Threads::threads_do(&init_gclabs);
+_workers->threads_do(&init_gclabs);
+_safepoint_workers->threads_do(&init_gclabs);
+// gclab can not be initialized early during VM startup, as it can not determinate its max_size.
+// Now, we will let WorkGang to initialize gclab when new worker is created.
+_workers->set_initialize_gclab();
+_scm->initialize(_max_workers);
+_full_gc->initialize(_gc_timer);
+ref_processing_init();
+_heuristics->initialize();
+}
+size_t ShenandoahHeap::used() const {
+return OrderAccess::load_acquire(&_used);
+}
+size_t ShenandoahHeap::committed() const {
+OrderAccess::acquire();
+return _committed;
+}
+void ShenandoahHeap::increase_committed(size_t bytes) {
+assert_heaplock_or_safepoint();
+_committed += bytes;
+}
+void ShenandoahHeap::decrease_committed(size_t bytes) {
+assert_heaplock_or_safepoint();
+_committed -= bytes;
+}
+void ShenandoahHeap::increase_used(size_t bytes) {
+Atomic::add(bytes, &_used);
+}
+void ShenandoahHeap::set_used(size_t bytes) {
+OrderAccess::release_store_fence(&_used, bytes);
+}
+void ShenandoahHeap::decrease_used(size_t bytes) {
+assert(used() >= bytes, "never decrease heap size by more than we've left");
+Atomic::sub(bytes, &_used);
+}
+void ShenandoahHeap::increase_allocated(size_t bytes) {
+Atomic::add(bytes, &_bytes_allocated_since_gc_start);
+}
+void ShenandoahHeap::notify_mutator_alloc_words(size_t words, bool waste) {
+size_t bytes = words * HeapWordSize;
+if (!waste) {
+increase_used(bytes);
+}
+increase_allocated(bytes);
+if (ShenandoahPacing) {
+control_thread()->pacing_notify_alloc(words);
+if (waste) {
+pacer()->claim_for_alloc(words, true);
+}
+}
+}
+size_t ShenandoahHeap::capacity() const {
+return num_regions() * ShenandoahHeapRegion::region_size_bytes();
+}
+size_t ShenandoahHeap::max_capacity() const {
+return _num_regions * ShenandoahHeapRegion::region_size_bytes();
+}
+size_t ShenandoahHeap::initial_capacity() const {
+return _initial_size;
+}
+bool ShenandoahHeap::is_in(const void* p) const {
+HeapWord* heap_base = (HeapWord*) base();
+HeapWord* last_region_end = heap_base + ShenandoahHeapRegion::region_size_words() * num_regions();
+return p >= heap_base && p < last_region_end;
+}
+void ShenandoahHeap::op_uncommit(double shrink_before) {
+assert (ShenandoahUncommit, "should be enabled");
+size_t count = 0;
+for (size_t i = 0; i < num_regions(); i++) {
+ShenandoahHeapRegion* r = get_region(i);
+if (r->is_empty_committed() && (r->empty_time() < shrink_before)) {
+ShenandoahHeapLocker locker(lock());
+if (r->is_empty_committed()) {
+r->make_uncommitted();
+count++;
+}
+}
+SpinPause(); // allow allocators to take the lock
+}
+if (count > 0) {
+log_info(gc)("Uncommitted " SIZE_FORMAT "M. Heap: " SIZE_FORMAT "M reserved, " SIZE_FORMAT "M committed, " SIZE_FORMAT "M used",
+count * ShenandoahHeapRegion::region_size_bytes() / M, capacity() / M, committed() / M, used() / M);
+control_thread()->notify_heap_changed();
+}
+}
+HeapWord* ShenandoahHeap::allocate_from_gclab_slow(Thread* thread, size_t size) {
+// New object should fit the GCLAB size
+size_t min_size = MAX2(size, PLAB::min_size());
+// Figure out size of new GCLAB, looking back at heuristics. Expand aggressively.
+size_t new_size = ShenandoahThreadLocalData::gclab_size(thread) * 2;
+new_size = MIN2(new_size, PLAB::max_size());
+new_size = MAX2(new_size, PLAB::min_size());
+// Record new heuristic value even if we take any shortcut. This captures
+// the case when moderately-sized objects always take a shortcut. At some point,
+// heuristics should catch up with them.
+ShenandoahThreadLocalData::set_gclab_size(thread, new_size);
+if (new_size < size) {
+// New size still does not fit the object. Fall back to shared allocation.
+// This avoids retiring perfectly good GCLABs, when we encounter a large object.
+return NULL;
+}
+// Retire current GCLAB, and allocate a new one.
+PLAB* gclab = ShenandoahThreadLocalData::gclab(thread);
+gclab->retire();
+size_t actual_size = 0;
+HeapWord* gclab_buf = allocate_new_gclab(min_size, new_size, &actual_size);
+if (gclab_buf == NULL) {
+return NULL;
+}
+assert (size <= actual_size, "allocation should fit");
+if (ZeroTLAB) {
+// ..and clear it.
+Copy::zero_to_words(gclab_buf, actual_size);
+} else {
+// ...and zap just allocated object.
+#ifdef ASSERT
+// Skip mangling the space corresponding to the object header to
+// ensure that the returned space is not considered parsable by
+// any concurrent GC thread.
+size_t hdr_size = oopDesc::header_size();
+Copy::fill_to_words(gclab_buf + hdr_size, actual_size - hdr_size, badHeapWordVal);
+#endif // ASSERT
+}
+gclab->set_buf(gclab_buf, actual_size);
+return gclab->allocate(size);
+}
+HeapWord* ShenandoahHeap::allocate_new_tlab(size_t min_size,
+size_t requested_size,
+size_t* actual_size) {
+ShenandoahAllocRequest req = ShenandoahAllocRequest::for_tlab(min_size, requested_size);
+HeapWord* res = allocate_memory(req);
+if (res != NULL) {
+*actual_size = req.actual_size();
+} else {
+*actual_size = 0;
+}
+return res;
+}
+HeapWord* ShenandoahHeap::allocate_new_gclab(size_t min_size,
+size_t word_size,
+size_t* actual_size) {
+ShenandoahAllocRequest req = ShenandoahAllocRequest::for_gclab(min_size, word_size);
+HeapWord* res = allocate_memory(req);
+if (res != NULL) {
+*actual_size = req.actual_size();
+} else {
+*actual_size = 0;
+}
+return res;
+}
+ShenandoahHeap* ShenandoahHeap::heap() {
+CollectedHeap* heap = Universe::heap();
+assert(heap != NULL, "Unitialized access to ShenandoahHeap::heap()");
+assert(heap->kind() == CollectedHeap::Shenandoah, "not a shenandoah heap");
+return (ShenandoahHeap*) heap;
+}
+ShenandoahHeap* ShenandoahHeap::heap_no_check() {
+CollectedHeap* heap = Universe::heap();
+return (ShenandoahHeap*) heap;
+}
+HeapWord* ShenandoahHeap::allocate_memory(ShenandoahAllocRequest& req) {
+ShenandoahAllocTrace trace_alloc(req.size(), req.type());
+intptr_t pacer_epoch = 0;
+bool in_new_region = false;
+HeapWord* result = NULL;
+if (req.is_mutator_alloc()) {
+if (ShenandoahPacing) {
+pacer()->pace_for_alloc(req.size());
+pacer_epoch = pacer()->epoch();
+}
+if (!ShenandoahAllocFailureALot || !should_inject_alloc_failure()) {
+result = allocate_memory_under_lock(req, in_new_region);
+}
+// Allocation failed, block until control thread reacted, then retry allocation.
+//
+// It might happen that one of the threads requesting allocation would unblock
+// way later after GC happened, only to fail the second allocation, because
+// other threads have already depleted the free storage. In this case, a better
+// strategy is to try again, as long as GC makes progress.
+//
+// Then, we need to make sure the allocation was retried after at least one
+// Full GC, which means we want to try more than ShenandoahFullGCThreshold times.
+size_t tries = 0;
+while (result == NULL && _progress_last_gc.is_set()) {
+tries++;
+control_thread()->handle_alloc_failure(req.size());
+result = allocate_memory_under_lock(req, in_new_region);
+}
+while (result == NULL && tries <= ShenandoahFullGCThreshold) {
+tries++;
+control_thread()->handle_alloc_failure(req.size());
+result = allocate_memory_under_lock(req, in_new_region);
+}
+} else {
+assert(req.is_gc_alloc(), "Can only accept GC allocs here");
+result = allocate_memory_under_lock(req, in_new_region);
+// Do not call handle_alloc_failure() here, because we cannot block.
+// The allocation failure would be handled by the WB slowpath with handle_alloc_failure_evac().
+}
+if (in_new_region) {
+control_thread()->notify_heap_changed();
+}
+if (result != NULL) {
+size_t requested = req.size();
+size_t actual = req.actual_size();
+assert (req.is_lab_alloc() || (requested == actual),
+"Only LAB allocations are elastic: %s, requested = " SIZE_FORMAT ", actual = " SIZE_FORMAT,
+ShenandoahAllocRequest::alloc_type_to_string(req.type()), requested, actual);
+if (req.is_mutator_alloc()) {
+notify_mutator_alloc_words(actual, false);
+// If we requested more than we were granted, give the rest back to pacer.
+// This only matters if we are in the same pacing epoch: do not try to unpace
+// over the budget for the other phase.
+if (ShenandoahPacing && (pacer_epoch > 0) && (requested > actual)) {
+pacer()->unpace_for_alloc(pacer_epoch, requested - actual);
+}
+} else {
+increase_used(actual*HeapWordSize);
+}
+}
+return result;
+}
+HeapWord* ShenandoahHeap::allocate_memory_under_lock(ShenandoahAllocRequest& req, bool& in_new_region) {
+ShenandoahHeapLocker locker(lock());
+return _free_set->allocate(req, in_new_region);
+}
+class ShenandoahMemAllocator : public MemAllocator {
+private:
+MemAllocator& _initializer;
+public:
+ShenandoahMemAllocator(MemAllocator& initializer, Klass* klass, size_t word_size, Thread* thread) :
+MemAllocator(klass, word_size + ShenandoahBrooksPointer::word_size(), thread),
+_initializer(initializer) {}
+protected:
+virtual HeapWord* mem_allocate(Allocation& allocation) const {
+HeapWord* result = MemAllocator::mem_allocate(allocation);
+// Initialize brooks-pointer
+if (result != NULL) {
+result += ShenandoahBrooksPointer::word_size();
+ShenandoahBrooksPointer::initialize(oop(result));
+assert(! ShenandoahHeap::heap()->in_collection_set(result), "never allocate in targetted region");
+}
+return result;
+}
+virtual oop initialize(HeapWord* mem) const {
+return _initializer.initialize(mem);
+}
+};
+oop ShenandoahHeap::obj_allocate(Klass* klass, int size, TRAPS) {
+ObjAllocator initializer(klass, size, THREAD);
+ShenandoahMemAllocator allocator(initializer, klass, size, THREAD);
+return allocator.allocate();
+}
+oop ShenandoahHeap::array_allocate(Klass* klass, int size, int length, bool do_zero, TRAPS) {
+ObjArrayAllocator initializer(klass, size, length, do_zero, THREAD);
+ShenandoahMemAllocator allocator(initializer, klass, size, THREAD);
+return allocator.allocate();
+}
+oop ShenandoahHeap::class_allocate(Klass* klass, int size, TRAPS) {
+ClassAllocator initializer(klass, size, THREAD);
+ShenandoahMemAllocator allocator(initializer, klass, size, THREAD);
+return allocator.allocate();
+}
+HeapWord* ShenandoahHeap::mem_allocate(size_t size,
+bool*  gc_overhead_limit_was_exceeded) {
+ShenandoahAllocRequest req = ShenandoahAllocRequest::for_shared(size);
+return allocate_memory(req);
+}
+MetaWord* ShenandoahHeap::satisfy_failed_metadata_allocation(ClassLoaderData* loader_data,
+size_t size,
+Metaspace::MetadataType mdtype) {
+MetaWord* result;
+// Inform metaspace OOM to GC heuristics if class unloading is possible.
+if (heuristics()->can_unload_classes()) {
+ShenandoahHeuristics* h = heuristics();
+h->record_metaspace_oom();
+}
+// Expand and retry allocation
+result = loader_data->metaspace_non_null()->expand_and_allocate(size, mdtype);
+if (result != NULL) {
+return result;
+}
+// Start full GC
+collect(GCCause::_metadata_GC_clear_soft_refs);
+// Retry allocation
+result = loader_data->metaspace_non_null()->allocate(size, mdtype);
+if (result != NULL) {
+return result;
+}
+// Expand and retry allocation
+result = loader_data->metaspace_non_null()->expand_and_allocate(size, mdtype);
+if (result != NULL) {
+return result;
+}
+// Out of memory
+return NULL;
+}
+void ShenandoahHeap::fill_with_dummy_object(HeapWord* start, HeapWord* end, bool zap) {
+HeapWord* obj = tlab_post_allocation_setup(start);
+CollectedHeap::fill_with_object(obj, end);
+}
+size_t ShenandoahHeap::min_dummy_object_size() const {
+return CollectedHeap::min_dummy_object_size() + ShenandoahBrooksPointer::word_size();
+}
+class ShenandoahEvacuateUpdateRootsClosure: public BasicOopIterateClosure {
+private:
+ShenandoahHeap* _heap;
+Thread* _thread;
+public:
+ShenandoahEvacuateUpdateRootsClosure() :
+_heap(ShenandoahHeap::heap()), _thread(Thread::current()) {
+}
+private:
+template <class T>
+void do_oop_work(T* p) {
+assert(_heap->is_evacuation_in_progress(), "Only do this when evacuation is in progress");
+T o = RawAccess<>::oop_load(p);
+if (! CompressedOops::is_null(o)) {
+oop obj = CompressedOops::decode_not_null(o);
+if (_heap->in_collection_set(obj)) {
+shenandoah_assert_marked(p, obj);
+oop resolved = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);
+if (oopDesc::equals_raw(resolved, obj)) {
+resolved = _heap->evacuate_object(obj, _thread);
+}
+RawAccess<IS_NOT_NULL>::oop_store(p, resolved);
+}
+}
+}
+public:
+void do_oop(oop* p) {
+do_oop_work(p);
+}
+void do_oop(narrowOop* p) {
+do_oop_work(p);
+}
+};
+class ShenandoahConcurrentEvacuateRegionObjectClosure : public ObjectClosure {
+private:
+ShenandoahHeap* const _heap;
+Thread* const _thread;
+public:
+ShenandoahConcurrentEvacuateRegionObjectClosure(ShenandoahHeap* heap) :
+_heap(heap), _thread(Thread::current()) {}
+void do_object(oop p) {
+shenandoah_assert_marked(NULL, p);
+if (oopDesc::equals_raw(p, ShenandoahBarrierSet::resolve_forwarded_not_null(p))) {
+_heap->evacuate_object(p, _thread);
+}
+}
+};
+class ShenandoahEvacuationTask : public AbstractGangTask {
+private:
+ShenandoahHeap* const _sh;
+ShenandoahCollectionSet* const _cs;
+bool _concurrent;
+public:
+ShenandoahEvacuationTask(ShenandoahHeap* sh,
+ShenandoahCollectionSet* cs,
+bool concurrent) :
+AbstractGangTask("Parallel Evacuation Task"),
+_sh(sh),
+_cs(cs),
+_concurrent(concurrent)
+{}
+void work(uint worker_id) {
+if (_concurrent) {
+ShenandoahConcurrentWorkerSession worker_session(worker_id);
+ShenandoahSuspendibleThreadSetJoiner stsj(ShenandoahSuspendibleWorkers);
+ShenandoahEvacOOMScope oom_evac_scope;
+do_work();
+} else {
+ShenandoahParallelWorkerSession worker_session(worker_id);
+ShenandoahEvacOOMScope oom_evac_scope;
+do_work();
+}
+}
+private:
+void do_work() {
+ShenandoahConcurrentEvacuateRegionObjectClosure cl(_sh);
+ShenandoahHeapRegion* r;
+while ((r =_cs->claim_next()) != NULL) {
+assert(r->has_live(), "all-garbage regions are reclaimed early");
+_sh->marked_object_iterate(r, &cl);
+if (ShenandoahPacing) {
+_sh->pacer()->report_evac(r->used() >> LogHeapWordSize);
+}
+if (_sh->check_cancelled_gc_and_yield(_concurrent)) {
+break;
+}
+}
+}
+};
+void ShenandoahHeap::trash_cset_regions() {
+ShenandoahHeapLocker locker(lock());
+ShenandoahCollectionSet* set = collection_set();
+ShenandoahHeapRegion* r;
+set->clear_current_index();
+while ((r = set->next()) != NULL) {
+r->make_trash();
+}
+collection_set()->clear();
+}
+void ShenandoahHeap::print_heap_regions_on(outputStream* st) const {
+st->print_cr("Heap Regions:");
+st->print_cr("EU=empty-uncommitted, EC=empty-committed, R=regular, H=humongous start, HC=humongous continuation, CS=collection set, T=trash, P=pinned");
+st->print_cr("BTE=bottom/top/end, U=used, T=TLAB allocs, G=GCLAB allocs, S=shared allocs, L=live data");
+st->print_cr("R=root, CP=critical pins, TAMS=top-at-mark-start (previous, next)");
+st->print_cr("SN=alloc sequence numbers (first mutator, last mutator, first gc, last gc)");
+for (size_t i = 0; i < num_regions(); i++) {
+get_region(i)->print_on(st);
+}
+}
+void ShenandoahHeap::trash_humongous_region_at(ShenandoahHeapRegion* start) {
+assert(start->is_humongous_start(), "reclaim regions starting with the first one");
+oop humongous_obj = oop(start->bottom() + ShenandoahBrooksPointer::word_size());
+size_t size = humongous_obj->size() + ShenandoahBrooksPointer::word_size();
+size_t required_regions = ShenandoahHeapRegion::required_regions(size * HeapWordSize);
+size_t index = start->region_number() + required_regions - 1;
+assert(!start->has_live(), "liveness must be zero");
+for(size_t i = 0; i < required_regions; i++) {
+// Reclaim from tail. Otherwise, assertion fails when printing region to trace log,
+// as it expects that every region belongs to a humongous region starting with a humongous start region.
+ShenandoahHeapRegion* region = get_region(index --);
+assert(region->is_humongous(), "expect correct humongous start or continuation");
+assert(!region->is_cset(), "Humongous region should not be in collection set");
+region->make_trash_immediate();
+}
+}
+class ShenandoahRetireGCLABClosure : public ThreadClosure {
+public:
+void do_thread(Thread* thread) {
+PLAB* gclab = ShenandoahThreadLocalData::gclab(thread);
+assert(gclab != NULL, "GCLAB should be initialized for %s", thread->name());
+gclab->retire();
+}
+};
+void ShenandoahHeap::make_parsable(bool retire_tlabs) {
+if (UseTLAB) {
+CollectedHeap::ensure_parsability(retire_tlabs);
+}
+ShenandoahRetireGCLABClosure cl;
+for (JavaThreadIteratorWithHandle jtiwh; JavaThread *t = jtiwh.next(); ) {
+cl.do_thread(t);
+}
+workers()->threads_do(&cl);
+_safepoint_workers->threads_do(&cl);
+}
+void ShenandoahHeap::resize_tlabs() {
+CollectedHeap::resize_all_tlabs();
+}
+class ShenandoahEvacuateUpdateRootsTask : public AbstractGangTask {
+private:
+ShenandoahRootEvacuator* _rp;
+public:
+ShenandoahEvacuateUpdateRootsTask(ShenandoahRootEvacuator* rp) :
+AbstractGangTask("Shenandoah evacuate and update roots"),
+_rp(rp) {}
+void work(uint worker_id) {
+ShenandoahParallelWorkerSession worker_session(worker_id);
+ShenandoahEvacOOMScope oom_evac_scope;
+ShenandoahEvacuateUpdateRootsClosure cl;
+MarkingCodeBlobClosure blobsCl(&cl, CodeBlobToOopClosure::FixRelocations);
+_rp->process_evacuate_roots(&cl, &blobsCl, worker_id);
+}
+};
+void ShenandoahHeap::evacuate_and_update_roots() {
+#if defined(COMPILER2) || INCLUDE_JVMCI
+DerivedPointerTable::clear();
+#endif
+assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "Only iterate roots while world is stopped");
+{
+ShenandoahRootEvacuator rp(this, workers()->active_workers(), ShenandoahPhaseTimings::init_evac);
+ShenandoahEvacuateUpdateRootsTask roots_task(&rp);
+workers()->run_task(&roots_task);
+}
+#if defined(COMPILER2) || INCLUDE_JVMCI
+DerivedPointerTable::update_pointers();
+#endif
+}
+void ShenandoahHeap::roots_iterate(OopClosure* cl) {
+assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "Only iterate roots while world is stopped");
+CodeBlobToOopClosure blobsCl(cl, false);
+CLDToOopClosure cldCl(cl, ClassLoaderData::_claim_strong);
+ShenandoahRootProcessor rp(this, 1, ShenandoahPhaseTimings::_num_phases);
+rp.process_all_roots(cl, NULL, &cldCl, &blobsCl, NULL, 0);
+}
+// Returns size in bytes
+size_t ShenandoahHeap::unsafe_max_tlab_alloc(Thread *thread) const {
+if (ShenandoahElasticTLAB) {
+// With Elastic TLABs, return the max allowed size, and let the allocation path
+// figure out the safe size for current allocation.
+return ShenandoahHeapRegion::max_tlab_size_bytes();
+} else {
+return MIN2(_free_set->unsafe_peek_free(), ShenandoahHeapRegion::max_tlab_size_bytes());
+}
+}
+size_t ShenandoahHeap::max_tlab_size() const {
+// Returns size in words
+return ShenandoahHeapRegion::max_tlab_size_words();
+}
+class ShenandoahRetireAndResetGCLABClosure : public ThreadClosure {
+public:
+void do_thread(Thread* thread) {
+PLAB* gclab = ShenandoahThreadLocalData::gclab(thread);
+gclab->retire();
+if (ShenandoahThreadLocalData::gclab_size(thread) > 0) {
+ShenandoahThreadLocalData::set_gclab_size(thread, 0);
+}
+}
+};
+void ShenandoahHeap::retire_and_reset_gclabs() {
+ShenandoahRetireAndResetGCLABClosure cl;
+for (JavaThreadIteratorWithHandle jtiwh; JavaThread *t = jtiwh.next(); ) {
+cl.do_thread(t);
+}
+workers()->threads_do(&cl);
+_safepoint_workers->threads_do(&cl);
+}
+void ShenandoahHeap::collect(GCCause::Cause cause) {
+control_thread()->request_gc(cause);
+}
+void ShenandoahHeap::do_full_collection(bool clear_all_soft_refs) {
+//assert(false, "Shouldn't need to do full collections");
+}
+CollectorPolicy* ShenandoahHeap::collector_policy() const {
+return _shenandoah_policy;
+}
+HeapWord* ShenandoahHeap::block_start(const void* addr) const {
+Space* sp = heap_region_containing(addr);
+if (sp != NULL) {
+return sp->block_start(addr);
+}
+return NULL;
+}
+size_t ShenandoahHeap::block_size(const HeapWord* addr) const {
+Space* sp = heap_region_containing(addr);
+assert(sp != NULL, "block_size of address outside of heap");
+return sp->block_size(addr);
+}
+bool ShenandoahHeap::block_is_obj(const HeapWord* addr) const {
+Space* sp = heap_region_containing(addr);
+return sp->block_is_obj(addr);
+}
+jlong ShenandoahHeap::millis_since_last_gc() {
+double v = heuristics()->time_since_last_gc() * 1000;
+assert(0 <= v && v <= max_jlong, "value should fit: %f", v);
+return (jlong)v;
+}
+void ShenandoahHeap::prepare_for_verify() {
+if (SafepointSynchronize::is_at_safepoint() || ! UseTLAB) {
+make_parsable(false);
+}
+}
+void ShenandoahHeap::print_gc_threads_on(outputStream* st) const {
+workers()->print_worker_threads_on(st);
+if (ShenandoahStringDedup::is_enabled()) {
+ShenandoahStringDedup::print_worker_threads_on(st);
+}
+}
+void ShenandoahHeap::gc_threads_do(ThreadClosure* tcl) const {
+workers()->threads_do(tcl);
+_safepoint_workers->threads_do(tcl);
+if (ShenandoahStringDedup::is_enabled()) {
+ShenandoahStringDedup::threads_do(tcl);
+}
+}
+void ShenandoahHeap::print_tracing_info() const {
+LogTarget(Info, gc, stats) lt;
+if (lt.is_enabled()) {
+ResourceMark rm;
+LogStream ls(lt);
+phase_timings()->print_on(&ls);
+ls.cr();
+ls.cr();
+shenandoah_policy()->print_gc_stats(&ls);
+ls.cr();
+ls.cr();
+if (ShenandoahPacing) {
+pacer()->print_on(&ls);
+}
+ls.cr();
+ls.cr();
+if (ShenandoahAllocationTrace) {
+assert(alloc_tracker() != NULL, "Must be");
+alloc_tracker()->print_on(&ls);
+} else {
+ls.print_cr("  Allocation tracing is disabled, use -XX:+ShenandoahAllocationTrace to enable.");
+}
+}
+}
+void ShenandoahHeap::verify(VerifyOption vo) {
+if (ShenandoahSafepoint::is_at_shenandoah_safepoint()) {
+if (ShenandoahVerify) {
+verifier()->verify_generic(vo);
+} else {
+// TODO: Consider allocating verification bitmaps on demand,
+// and turn this on unconditionally.
+}
+}
+}
+size_t ShenandoahHeap::tlab_capacity(Thread *thr) const {
+return _free_set->capacity();
+}
+class ObjectIterateScanRootClosure : public BasicOopIterateClosure {
+private:
+MarkBitMap* _bitmap;
+Stack<oop,mtGC>* _oop_stack;
+template <class T>
+void do_oop_work(T* p) {
+T o = RawAccess<>::oop_load(p);
+if (!CompressedOops::is_null(o)) {
+oop obj = CompressedOops::decode_not_null(o);
+obj = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);
+assert(oopDesc::is_oop(obj), "must be a valid oop");
+if (!_bitmap->is_marked((HeapWord*) obj)) {
+_bitmap->mark((HeapWord*) obj);
+_oop_stack->push(obj);
+}
+}
+}
+public:
+ObjectIterateScanRootClosure(MarkBitMap* bitmap, Stack<oop,mtGC>* oop_stack) :
+_bitmap(bitmap), _oop_stack(oop_stack) {}
+void do_oop(oop* p)       { do_oop_work(p); }
+void do_oop(narrowOop* p) { do_oop_work(p); }
+};
+/*
+* This is public API, used in preparation of object_iterate().
+* Since we don't do linear scan of heap in object_iterate() (see comment below), we don't
+* need to make the heap parsable. For Shenandoah-internal linear heap scans that we can
+* control, we call SH::make_tlabs_parsable().
+*/
+void ShenandoahHeap::ensure_parsability(bool retire_tlabs) {
+// No-op.
+}
+/*
+* Iterates objects in the heap. This is public API, used for, e.g., heap dumping.
+*
+* We cannot safely iterate objects by doing a linear scan at random points in time. Linear
+* scanning needs to deal with dead objects, which may have dead Klass* pointers (e.g.
+* calling oopDesc::size() would crash) or dangling reference fields (crashes) etc. Linear
+* scanning therefore depends on having a valid marking bitmap to support it. However, we only
+* have a valid marking bitmap after successful marking. In particular, we *don't* have a valid
+* marking bitmap during marking, after aborted marking or during/after cleanup (when we just
+* wiped the bitmap in preparation for next marking).
+*
+* For all those reasons, we implement object iteration as a single marking traversal, reporting
+* objects as we mark+traverse through the heap, starting from GC roots. JVMTI IterateThroughHeap
+* is allowed to report dead objects, but is not required to do so.
+*/
+void ShenandoahHeap::object_iterate(ObjectClosure* cl) {
+assert(SafepointSynchronize::is_at_safepoint(), "safe iteration is only available during safepoints");
+if (!os::commit_memory((char*)_aux_bitmap_region.start(), _aux_bitmap_region.byte_size(), false)) {
+log_warning(gc)("Could not commit native memory for auxiliary marking bitmap for heap iteration");
+return;
+}
+// Reset bitmap
+_aux_bit_map.clear();
+Stack<oop,mtGC> oop_stack;
+// First, we process all GC roots. This populates the work stack with initial objects.
+ShenandoahRootProcessor rp(this, 1, ShenandoahPhaseTimings::_num_phases);
+ObjectIterateScanRootClosure oops(&_aux_bit_map, &oop_stack);
+CLDToOopClosure clds(&oops, ClassLoaderData::_claim_none);
+CodeBlobToOopClosure blobs(&oops, false);
+rp.process_all_roots(&oops, &oops, &clds, &blobs, NULL, 0);
+// Work through the oop stack to traverse heap.
+while (! oop_stack.is_empty()) {
+oop obj = oop_stack.pop();
+assert(oopDesc::is_oop(obj), "must be a valid oop");
+cl->do_object(obj);
+obj->oop_iterate(&oops);
+}
+assert(oop_stack.is_empty(), "should be empty");
+if (!os::uncommit_memory((char*)_aux_bitmap_region.start(), _aux_bitmap_region.byte_size())) {
+log_warning(gc)("Could not uncommit native memory for auxiliary marking bitmap for heap iteration");
+}
+}
+void ShenandoahHeap::safe_object_iterate(ObjectClosure* cl) {
+assert(SafepointSynchronize::is_at_safepoint(), "safe iteration is only available during safepoints");
+object_iterate(cl);
+}
+void ShenandoahHeap::heap_region_iterate(ShenandoahHeapRegionClosure* blk) const {
+for (size_t i = 0; i < num_regions(); i++) {
+ShenandoahHeapRegion* current = get_region(i);
+blk->heap_region_do(current);
+}
+}
+class ShenandoahParallelHeapRegionTask : public AbstractGangTask {
+private:
+ShenandoahHeap* const _heap;
+ShenandoahHeapRegionClosure* const _blk;
+DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile size_t));
+volatile size_t _index;
+DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, 0);
+public:
+ShenandoahParallelHeapRegionTask(ShenandoahHeapRegionClosure* blk) :
+AbstractGangTask("Parallel Region Task"),
+_heap(ShenandoahHeap::heap()), _blk(blk), _index(0) {}
+void work(uint worker_id) {
+size_t stride = ShenandoahParallelRegionStride;
+size_t max = _heap->num_regions();
+while (_index < max) {
+size_t cur = Atomic::add(stride, &_index) - stride;
+size_t start = cur;
+size_t end = MIN2(cur + stride, max);
+if (start >= max) break;
+for (size_t i = cur; i < end; i++) {
+ShenandoahHeapRegion* current = _heap->get_region(i);
+_blk->heap_region_do(current);
+}
+}
+}
+};
+void ShenandoahHeap::parallel_heap_region_iterate(ShenandoahHeapRegionClosure* blk) const {
+assert(blk->is_thread_safe(), "Only thread-safe closures here");
+if (num_regions() > ShenandoahParallelRegionStride) {
+ShenandoahParallelHeapRegionTask task(blk);
+workers()->run_task(&task);
+} else {
+heap_region_iterate(blk);
+}
+}
+class ShenandoahClearLivenessClosure : public ShenandoahHeapRegionClosure {
+private:
+ShenandoahMarkingContext* const _ctx;
+public:
+ShenandoahClearLivenessClosure() : _ctx(ShenandoahHeap::heap()->marking_context()) {}
+void heap_region_do(ShenandoahHeapRegion* r) {
+if (r->is_active()) {
+r->clear_live_data();
+_ctx->capture_top_at_mark_start(r);
+} else {
+assert(!r->has_live(), "Region " SIZE_FORMAT " should have no live data", r->region_number());
+assert(_ctx->top_at_mark_start(r) == r->top(),
+"Region " SIZE_FORMAT " should already have correct TAMS", r->region_number());
+}
+}
+bool is_thread_safe() { return true; }
+};
+void ShenandoahHeap::op_init_mark() {
+assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "Should be at safepoint");
+assert(Thread::current()->is_VM_thread(), "can only do this in VMThread");
+assert(marking_context()->is_bitmap_clear(), "need clear marking bitmap");
+assert(!marking_context()->is_complete(), "should not be complete");
+if (ShenandoahVerify) {
+verifier()->verify_before_concmark();
+}
+if (VerifyBeforeGC) {
+Universe::verify();
+}
+set_concurrent_mark_in_progress(true);
+// We need to reset all TLABs because we'd lose marks on all objects allocated in them.
+{
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::make_parsable);
+make_parsable(true);
+}
+{
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::clear_liveness);
+ShenandoahClearLivenessClosure clc;
+parallel_heap_region_iterate(&clc);
+}
+// Make above changes visible to worker threads
+OrderAccess::fence();
+concurrent_mark()->mark_roots(ShenandoahPhaseTimings::scan_roots);
+if (UseTLAB) {
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::resize_tlabs);
+resize_tlabs();
+}
+if (ShenandoahPacing) {
+pacer()->setup_for_mark();
+}
+}
+void ShenandoahHeap::op_mark() {
+concurrent_mark()->mark_from_roots();
+}
+class ShenandoahCompleteLivenessClosure : public ShenandoahHeapRegionClosure {
+private:
+ShenandoahMarkingContext* const _ctx;
+public:
+ShenandoahCompleteLivenessClosure() : _ctx(ShenandoahHeap::heap()->complete_marking_context()) {}
+void heap_region_do(ShenandoahHeapRegion* r) {
+if (r->is_active()) {
+HeapWord *tams = _ctx->top_at_mark_start(r);
+HeapWord *top = r->top();
+if (top > tams) {
+r->increase_live_data_alloc_words(pointer_delta(top, tams));
+}
+} else {
+assert(!r->has_live(), "Region " SIZE_FORMAT " should have no live data", r->region_number());
+assert(_ctx->top_at_mark_start(r) == r->top(),
+"Region " SIZE_FORMAT " should have correct TAMS", r->region_number());
+}
+}
+bool is_thread_safe() { return true; }
+};
+void ShenandoahHeap::op_final_mark() {
+assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "Should be at safepoint");
+// It is critical that we
+// evacuate roots right after finishing marking, so that we don't
+// get unmarked objects in the roots.
+if (!cancelled_gc()) {
+concurrent_mark()->finish_mark_from_roots(/* full_gc = */ false);
+if (has_forwarded_objects()) {
+concurrent_mark()->update_roots(ShenandoahPhaseTimings::update_roots);
+}
+stop_concurrent_marking();
+{
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::complete_liveness);
+// All allocations past TAMS are implicitly live, adjust the region data.
+// Bitmaps/TAMS are swapped at this point, so we need to poll complete bitmap.
+ShenandoahCompleteLivenessClosure cl;
+parallel_heap_region_iterate(&cl);
+}
+{
+ShenandoahGCPhase prepare_evac(ShenandoahPhaseTimings::prepare_evac);
+make_parsable(true);
+trash_cset_regions();
+{
+ShenandoahHeapLocker locker(lock());
+_collection_set->clear();
+_free_set->clear();
+heuristics()->choose_collection_set(_collection_set);
+_free_set->rebuild();
+}
+}
+// If collection set has candidates, start evacuation.
+// Otherwise, bypass the rest of the cycle.
+if (!collection_set()->is_empty()) {
+ShenandoahGCPhase init_evac(ShenandoahPhaseTimings::init_evac);
+if (ShenandoahVerify) {
+verifier()->verify_before_evacuation();
+}
+set_evacuation_in_progress(true);
+// From here on, we need to update references.
+set_has_forwarded_objects(true);
+evacuate_and_update_roots();
+if (ShenandoahPacing) {
+pacer()->setup_for_evac();
+}
+} else {
+if (ShenandoahVerify) {
+verifier()->verify_after_concmark();
+}
+if (VerifyAfterGC) {
+Universe::verify();
+}
+}
+} else {
+concurrent_mark()->cancel();
+stop_concurrent_marking();
+if (process_references()) {
+// Abandon reference processing right away: pre-cleaning must have failed.
+ReferenceProcessor *rp = ref_processor();
+rp->disable_discovery();
+rp->abandon_partial_discovery();
+rp->verify_no_references_recorded();
+}
+}
+}
+void ShenandoahHeap::op_final_evac() {
+assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "Should be at safepoint");
+set_evacuation_in_progress(false);
+retire_and_reset_gclabs();
+if (ShenandoahVerify) {
+verifier()->verify_after_evacuation();
+}
+if (VerifyAfterGC) {
+Universe::verify();
+}
+}
+void ShenandoahHeap::op_conc_evac() {
+ShenandoahEvacuationTask task(this, _collection_set, true);
+workers()->run_task(&task);
+}
+void ShenandoahHeap::op_stw_evac() {
+ShenandoahEvacuationTask task(this, _collection_set, false);
+workers()->run_task(&task);
+}
+void ShenandoahHeap::op_updaterefs() {
+update_heap_references(true);
+}
+void ShenandoahHeap::op_cleanup() {
+free_set()->recycle_trash();
+}
+void ShenandoahHeap::op_reset() {
+reset_mark_bitmap();
+}
+void ShenandoahHeap::op_preclean() {
+concurrent_mark()->preclean_weak_refs();
+}
+void ShenandoahHeap::op_init_traversal() {
+traversal_gc()->init_traversal_collection();
+}
+void ShenandoahHeap::op_traversal() {
+traversal_gc()->concurrent_traversal_collection();
+}
+void ShenandoahHeap::op_final_traversal() {
+traversal_gc()->final_traversal_collection();
+}
+void ShenandoahHeap::op_full(GCCause::Cause cause) {
+ShenandoahMetricsSnapshot metrics;
+metrics.snap_before();
+full_gc()->do_it(cause);
+if (UseTLAB) {
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::full_gc_resize_tlabs);
+resize_all_tlabs();
+}
+metrics.snap_after();
+metrics.print();
+if (metrics.is_good_progress("Full GC")) {
+_progress_last_gc.set();
+} else {
+// Nothing to do. Tell the allocation path that we have failed to make
+// progress, and it can finally fail.
+_progress_last_gc.unset();
+}
+}
+void ShenandoahHeap::op_degenerated(ShenandoahDegenPoint point) {
+// Degenerated GC is STW, but it can also fail. Current mechanics communicates
+// GC failure via cancelled_concgc() flag. So, if we detect the failure after
+// some phase, we have to upgrade the Degenerate GC to Full GC.
+clear_cancelled_gc();
+ShenandoahMetricsSnapshot metrics;
+metrics.snap_before();
+switch (point) {
+case _degenerated_traversal:
+{
+// Drop the collection set. Note: this leaves some already forwarded objects
+// behind, which may be problematic, see comments for ShenandoahEvacAssist
+// workarounds in ShenandoahTraversalHeuristics.
+ShenandoahHeapLocker locker(lock());
+collection_set()->clear_current_index();
+for (size_t i = 0; i < collection_set()->count(); i++) {
+ShenandoahHeapRegion* r = collection_set()->next();
+r->make_regular_bypass();
+}
+collection_set()->clear();
+}
+op_final_traversal();
+op_cleanup();
+return;
+// The cases below form the Duff's-like device: it describes the actual GC cycle,
+// but enters it at different points, depending on which concurrent phase had
+// degenerated.
+case _degenerated_outside_cycle:
+// We have degenerated from outside the cycle, which means something is bad with
+// the heap, most probably heavy humongous fragmentation, or we are very low on free
+// space. It makes little sense to wait for Full GC to reclaim as much as it can, when
+// we can do the most aggressive degen cycle, which includes processing references and
+// class unloading, unless those features are explicitly disabled.
+//
+// Note that we can only do this for "outside-cycle" degens, otherwise we would risk
+// changing the cycle parameters mid-cycle during concurrent -> degenerated handover.
+set_process_references(heuristics()->can_process_references());
+set_unload_classes(heuristics()->can_unload_classes());
+if (heuristics()->can_do_traversal_gc()) {
+// Not possible to degenerate from here, upgrade to Full GC right away.
+cancel_gc(GCCause::_shenandoah_upgrade_to_full_gc);
+op_degenerated_fail();
+return;
+}
+op_reset();
+op_init_mark();
+if (cancelled_gc()) {
+op_degenerated_fail();
+return;
+}
+case _degenerated_mark:
+op_final_mark();
+if (cancelled_gc()) {
+op_degenerated_fail();
+return;
+}
+op_cleanup();
+case _degenerated_evac:
+// If heuristics thinks we should do the cycle, this flag would be set,
+// and we can do evacuation. Otherwise, it would be the shortcut cycle.
+if (is_evacuation_in_progress()) {
+// Degeneration under oom-evac protocol might have left some objects in
+// collection set un-evacuated. Restart evacuation from the beginning to
+// capture all objects. For all the objects that are already evacuated,
+// it would be a simple check, which is supposed to be fast. This is also
+// safe to do even without degeneration, as CSet iterator is at beginning
+// in preparation for evacuation anyway.
+collection_set()->clear_current_index();
+op_stw_evac();
+if (cancelled_gc()) {
+op_degenerated_fail();
+return;
+}
+}
+// If heuristics thinks we should do the cycle, this flag would be set,
+// and we need to do update-refs. Otherwise, it would be the shortcut cycle.
+if (has_forwarded_objects()) {
+op_init_updaterefs();
+if (cancelled_gc()) {
+op_degenerated_fail();
+return;
+}
+}
+case _degenerated_updaterefs:
+if (has_forwarded_objects()) {
+op_final_updaterefs();
+if (cancelled_gc()) {
+op_degenerated_fail();
+return;
+}
+}
+op_cleanup();
+break;
+default:
+ShouldNotReachHere();
+}
+if (ShenandoahVerify) {
+verifier()->verify_after_degenerated();
+}
+if (VerifyAfterGC) {
+Universe::verify();
+}
+metrics.snap_after();
+metrics.print();
+// Check for futility and fail. There is no reason to do several back-to-back Degenerated cycles,
+// because that probably means the heap is overloaded and/or fragmented.
+if (!metrics.is_good_progress("Degenerated GC")) {
+_progress_last_gc.unset();
+cancel_gc(GCCause::_shenandoah_upgrade_to_full_gc);
+op_degenerated_futile();
+} else {
+_progress_last_gc.set();
+}
+}
+void ShenandoahHeap::op_degenerated_fail() {
+log_info(gc)("Cannot finish degeneration, upgrading to Full GC");
+shenandoah_policy()->record_degenerated_upgrade_to_full();
+op_full(GCCause::_shenandoah_upgrade_to_full_gc);
+}
+void ShenandoahHeap::op_degenerated_futile() {
+shenandoah_policy()->record_degenerated_upgrade_to_full();
+op_full(GCCause::_shenandoah_upgrade_to_full_gc);
+}
+void ShenandoahHeap::stop_concurrent_marking() {
+assert(is_concurrent_mark_in_progress(), "How else could we get here?");
+if (!cancelled_gc()) {
+// If we needed to update refs, and concurrent marking has been cancelled,
+// we need to finish updating references.
+set_has_forwarded_objects(false);
+mark_complete_marking_context();
+}
+set_concurrent_mark_in_progress(false);
+}
+void ShenandoahHeap::force_satb_flush_all_threads() {
+if (!is_concurrent_mark_in_progress() && !is_concurrent_traversal_in_progress()) {
+// No need to flush SATBs
+return;
+}
+for (JavaThreadIteratorWithHandle jtiwh; JavaThread *t = jtiwh.next(); ) {
+ShenandoahThreadLocalData::set_force_satb_flush(t, true);
+}
+// The threads are not "acquiring" their thread-local data, but it does not
+// hurt to "release" the updates here anyway.
+OrderAccess::fence();
+}
+void ShenandoahHeap::set_gc_state_all_threads(char state) {
+for (JavaThreadIteratorWithHandle jtiwh; JavaThread *t = jtiwh.next(); ) {
+ShenandoahThreadLocalData::set_gc_state(t, state);
+}
+}
+void ShenandoahHeap::set_gc_state_mask(uint mask, bool value) {
+assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "Should really be Shenandoah safepoint");
+_gc_state.set_cond(mask, value);
+set_gc_state_all_threads(_gc_state.raw_value());
+}
+void ShenandoahHeap::set_concurrent_mark_in_progress(bool in_progress) {
+set_gc_state_mask(MARKING, in_progress);
+ShenandoahBarrierSet::satb_mark_queue_set().set_active_all_threads(in_progress, !in_progress);
+}
+void ShenandoahHeap::set_concurrent_traversal_in_progress(bool in_progress) {
+set_gc_state_mask(TRAVERSAL | HAS_FORWARDED, in_progress);
+ShenandoahBarrierSet::satb_mark_queue_set().set_active_all_threads(in_progress, !in_progress);
+}
+void ShenandoahHeap::set_evacuation_in_progress(bool in_progress) {
+assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "Only call this at safepoint");
+set_gc_state_mask(EVACUATION, in_progress);
+}
+HeapWord* ShenandoahHeap::tlab_post_allocation_setup(HeapWord* obj) {
+// Initialize Brooks pointer for the next object
+HeapWord* result = obj + ShenandoahBrooksPointer::word_size();
+ShenandoahBrooksPointer::initialize(oop(result));
+return result;
+}
+ShenandoahForwardedIsAliveClosure::ShenandoahForwardedIsAliveClosure() :
+_mark_context(ShenandoahHeap::heap()->marking_context()) {
+}
+ShenandoahIsAliveClosure::ShenandoahIsAliveClosure() :
+_mark_context(ShenandoahHeap::heap()->marking_context()) {
+}
+bool ShenandoahForwardedIsAliveClosure::do_object_b(oop obj) {
+if (CompressedOops::is_null(obj)) {
+return false;
+}
+obj = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);
+shenandoah_assert_not_forwarded_if(NULL, obj, ShenandoahHeap::heap()->is_concurrent_mark_in_progress() || ShenandoahHeap::heap()->is_concurrent_traversal_in_progress());
+return _mark_context->is_marked(obj);
+}
+bool ShenandoahIsAliveClosure::do_object_b(oop obj) {
+if (CompressedOops::is_null(obj)) {
+return false;
+}
+shenandoah_assert_not_forwarded(NULL, obj);
+return _mark_context->is_marked(obj);
+}
+void ShenandoahHeap::ref_processing_init() {
+assert(_max_workers > 0, "Sanity");
+_ref_processor =
+new ReferenceProcessor(&_subject_to_discovery,  // is_subject_to_discovery
+ParallelRefProcEnabled,  // MT processing
+_max_workers,            // Degree of MT processing
+true,                    // MT discovery
+_max_workers,            // Degree of MT discovery
+false,                   // Reference discovery is not atomic
+NULL,                    // No closure, should be installed before use
+true);                   // Scale worker threads
+shenandoah_assert_rp_isalive_not_installed();
+}
+GCTracer* ShenandoahHeap::tracer() {
+return shenandoah_policy()->tracer();
+}
+size_t ShenandoahHeap::tlab_used(Thread* thread) const {
+return _free_set->used();
+}
+void ShenandoahHeap::cancel_gc(GCCause::Cause cause) {
+if (try_cancel_gc()) {
+FormatBuffer<> msg("Cancelling GC: %s", GCCause::to_string(cause));
+log_info(gc)("%s", msg.buffer());
+Events::log(Thread::current(), "%s", msg.buffer());
+}
+}
+uint ShenandoahHeap::max_workers() {
+return _max_workers;
+}
+void ShenandoahHeap::stop() {
+// The shutdown sequence should be able to terminate when GC is running.
+// Step 0. Notify policy to disable event recording.
+_shenandoah_policy->record_shutdown();
+// Step 1. Notify control thread that we are in shutdown.
+// Note that we cannot do that with stop(), because stop() is blocking and waits for the actual shutdown.
+// Doing stop() here would wait for the normal GC cycle to complete, never falling through to cancel below.
+control_thread()->prepare_for_graceful_shutdown();
+// Step 2. Notify GC workers that we are cancelling GC.
+cancel_gc(GCCause::_shenandoah_stop_vm);
+// Step 3. Wait until GC worker exits normally.
+control_thread()->stop();
+// Step 4. Stop String Dedup thread if it is active
+if (ShenandoahStringDedup::is_enabled()) {
+ShenandoahStringDedup::stop();
+}
+}
+void ShenandoahHeap::unload_classes_and_cleanup_tables(bool full_gc) {
+assert(heuristics()->can_unload_classes(), "Class unloading should be enabled");
+ShenandoahGCPhase root_phase(full_gc ?
+ShenandoahPhaseTimings::full_gc_purge :
+ShenandoahPhaseTimings::purge);
+ShenandoahIsAliveSelector alive;
+BoolObjectClosure* is_alive = alive.is_alive_closure();
+bool purged_class;
+// Unload classes and purge SystemDictionary.
+{
+ShenandoahGCPhase phase(full_gc ?
+ShenandoahPhaseTimings::full_gc_purge_class_unload :
+ShenandoahPhaseTimings::purge_class_unload);
+purged_class = SystemDictionary::do_unloading(gc_timer());
+}
+{
+ShenandoahGCPhase phase(full_gc ?
+ShenandoahPhaseTimings::full_gc_purge_par :
+ShenandoahPhaseTimings::purge_par);
+uint active = _workers->active_workers();
+StringDedupUnlinkOrOopsDoClosure dedup_cl(is_alive, NULL);
+ParallelCleaningTask unlink_task(is_alive, &dedup_cl, active, purged_class);
+_workers->run_task(&unlink_task);
+}
+if (ShenandoahStringDedup::is_enabled()) {
+ShenandoahGCPhase phase(full_gc ?
+ShenandoahPhaseTimings::full_gc_purge_string_dedup :
+ShenandoahPhaseTimings::purge_string_dedup);
+ShenandoahStringDedup::parallel_cleanup();
+}
+{
+ShenandoahGCPhase phase(full_gc ?
+ShenandoahPhaseTimings::full_gc_purge_cldg :
+ShenandoahPhaseTimings::purge_cldg);
+ClassLoaderDataGraph::purge();
+}
+}
+void ShenandoahHeap::set_has_forwarded_objects(bool cond) {
+set_gc_state_mask(HAS_FORWARDED, cond);
+}
+void ShenandoahHeap::set_process_references(bool pr) {
+_process_references.set_cond(pr);
+}
+void ShenandoahHeap::set_unload_classes(bool uc) {
+_unload_classes.set_cond(uc);
+}
+bool ShenandoahHeap::process_references() const {
+return _process_references.is_set();
+}
+bool ShenandoahHeap::unload_classes() const {
+return _unload_classes.is_set();
+}
+address ShenandoahHeap::in_cset_fast_test_addr() {
+ShenandoahHeap* heap = ShenandoahHeap::heap();
+assert(heap->collection_set() != NULL, "Sanity");
+return (address) heap->collection_set()->biased_map_address();
+}
+address ShenandoahHeap::cancelled_gc_addr() {
+return (address) ShenandoahHeap::heap()->_cancelled_gc.addr_of();
+}
+address ShenandoahHeap::gc_state_addr() {
+return (address) ShenandoahHeap::heap()->_gc_state.addr_of();
+}
+size_t ShenandoahHeap::bytes_allocated_since_gc_start() {
+return OrderAccess::load_acquire(&_bytes_allocated_since_gc_start);
+}
+void ShenandoahHeap::reset_bytes_allocated_since_gc_start() {
+OrderAccess::release_store_fence(&_bytes_allocated_since_gc_start, (size_t)0);
+}
+void ShenandoahHeap::set_degenerated_gc_in_progress(bool in_progress) {
+_degenerated_gc_in_progress.set_cond(in_progress);
+}
+void ShenandoahHeap::set_full_gc_in_progress(bool in_progress) {
+_full_gc_in_progress.set_cond(in_progress);
+}
+void ShenandoahHeap::set_full_gc_move_in_progress(bool in_progress) {
+assert (is_full_gc_in_progress(), "should be");
+_full_gc_move_in_progress.set_cond(in_progress);
+}
+void ShenandoahHeap::set_update_refs_in_progress(bool in_progress) {
+set_gc_state_mask(UPDATEREFS, in_progress);
+}
+void ShenandoahHeap::register_nmethod(nmethod* nm) {
+ShenandoahCodeRoots::add_nmethod(nm);
+}
+void ShenandoahHeap::unregister_nmethod(nmethod* nm) {
+ShenandoahCodeRoots::remove_nmethod(nm);
+}
+oop ShenandoahHeap::pin_object(JavaThread* thr, oop o) {
+o = ShenandoahBarrierSet::barrier_set()->write_barrier(o);
+ShenandoahHeapLocker locker(lock());
+heap_region_containing(o)->make_pinned();
+return o;
+}
+void ShenandoahHeap::unpin_object(JavaThread* thr, oop o) {
+o = ShenandoahBarrierSet::barrier_set()->read_barrier(o);
+ShenandoahHeapLocker locker(lock());
+heap_region_containing(o)->make_unpinned();
+}
+GCTimer* ShenandoahHeap::gc_timer() const {
+return _gc_timer;
+}
+#ifdef ASSERT
+void ShenandoahHeap::assert_gc_workers(uint nworkers) {
+assert(nworkers > 0 && nworkers <= max_workers(), "Sanity");
+if (ShenandoahSafepoint::is_at_shenandoah_safepoint()) {
+if (UseDynamicNumberOfGCThreads ||
+(FLAG_IS_DEFAULT(ParallelGCThreads) && ForceDynamicNumberOfGCThreads)) {
+assert(nworkers <= ParallelGCThreads, "Cannot use more than it has");
+} else {
+// Use ParallelGCThreads inside safepoints
+assert(nworkers == ParallelGCThreads, "Use ParalleGCThreads within safepoints");
+}
+} else {
+if (UseDynamicNumberOfGCThreads ||
+(FLAG_IS_DEFAULT(ConcGCThreads) && ForceDynamicNumberOfGCThreads)) {
+assert(nworkers <= ConcGCThreads, "Cannot use more than it has");
+} else {
+// Use ConcGCThreads outside safepoints
+assert(nworkers == ConcGCThreads, "Use ConcGCThreads outside safepoints");
+}
+}
+}
+#endif
+ShenandoahVerifier* ShenandoahHeap::verifier() {
+guarantee(ShenandoahVerify, "Should be enabled");
+assert (_verifier != NULL, "sanity");
+return _verifier;
+}
+template<class T>
+class ShenandoahUpdateHeapRefsTask : public AbstractGangTask {
+private:
+T cl;
+ShenandoahHeap* _heap;
+ShenandoahRegionIterator* _regions;
+bool _concurrent;
+public:
+ShenandoahUpdateHeapRefsTask(ShenandoahRegionIterator* regions, bool concurrent) :
+AbstractGangTask("Concurrent Update References Task"),
+cl(T()),
+_heap(ShenandoahHeap::heap()),
+_regions(regions),
+_concurrent(concurrent) {
+}
+void work(uint worker_id) {
+if (_concurrent) {
+ShenandoahConcurrentWorkerSession worker_session(worker_id);
+ShenandoahSuspendibleThreadSetJoiner stsj(ShenandoahSuspendibleWorkers);
+do_work();
+} else {
+ShenandoahParallelWorkerSession worker_session(worker_id);
+do_work();
+}
+}
+private:
+void do_work() {
+ShenandoahHeapRegion* r = _regions->next();
+ShenandoahMarkingContext* const ctx = _heap->complete_marking_context();
+while (r != NULL) {
+HeapWord* top_at_start_ur = r->concurrent_iteration_safe_limit();
+assert (top_at_start_ur >= r->bottom(), "sanity");
+if (r->is_active() && !r->is_cset()) {
+_heap->marked_object_oop_iterate(r, &cl, top_at_start_ur);
+}
+if (ShenandoahPacing) {
+_heap->pacer()->report_updaterefs(pointer_delta(top_at_start_ur, r->bottom()));
+}
+if (_heap->check_cancelled_gc_and_yield(_concurrent)) {
+return;
+}
+r = _regions->next();
+}
+}
+};
+void ShenandoahHeap::update_heap_references(bool concurrent) {
+ShenandoahUpdateHeapRefsTask<ShenandoahUpdateHeapRefsClosure> task(&_update_refs_iterator, concurrent);
+workers()->run_task(&task);
+}
+void ShenandoahHeap::op_init_updaterefs() {
+assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "must be at safepoint");
+set_evacuation_in_progress(false);
+retire_and_reset_gclabs();
+if (ShenandoahVerify) {
+verifier()->verify_before_updaterefs();
+}
+set_update_refs_in_progress(true);
+make_parsable(true);
+for (uint i = 0; i < num_regions(); i++) {
+ShenandoahHeapRegion* r = get_region(i);
+r->set_concurrent_iteration_safe_limit(r->top());
+}
+// Reset iterator.
+_update_refs_iterator.reset();
+if (ShenandoahPacing) {
+pacer()->setup_for_updaterefs();
+}
+}
+void ShenandoahHeap::op_final_updaterefs() {
+assert(ShenandoahSafepoint::is_at_shenandoah_safepoint(), "must be at safepoint");
+// Check if there is left-over work, and finish it
+if (_update_refs_iterator.has_next()) {
+ShenandoahGCPhase final_work(ShenandoahPhaseTimings::final_update_refs_finish_work);
+// Finish updating references where we left off.
+clear_cancelled_gc();
+update_heap_references(false);
+}
+// Clear cancelled GC, if set. On cancellation path, the block before would handle
+// everything. On degenerated paths, cancelled gc would not be set anyway.
+if (cancelled_gc()) {
+clear_cancelled_gc();
+}
+assert(!cancelled_gc(), "Should have been done right before");
+concurrent_mark()->update_roots(is_degenerated_gc_in_progress() ?
+ShenandoahPhaseTimings::degen_gc_update_roots:
+ShenandoahPhaseTimings::final_update_refs_roots);
+ShenandoahGCPhase final_update_refs(ShenandoahPhaseTimings::final_update_refs_recycle);
+trash_cset_regions();
+set_has_forwarded_objects(false);
+set_update_refs_in_progress(false);
+if (ShenandoahVerify) {
+verifier()->verify_after_updaterefs();
+}
+if (VerifyAfterGC) {
+Universe::verify();
+}
+{
+ShenandoahHeapLocker locker(lock());
+_free_set->rebuild();
+}
+}
+#ifdef ASSERT
+void ShenandoahHeap::assert_heaplock_owned_by_current_thread() {
+_lock.assert_owned_by_current_thread();
+}
+void ShenandoahHeap::assert_heaplock_not_owned_by_current_thread() {
+_lock.assert_not_owned_by_current_thread();
+}
+void ShenandoahHeap::assert_heaplock_or_safepoint() {
+_lock.assert_owned_by_current_thread_or_safepoint();
+}
+#endif
+void ShenandoahHeap::print_extended_on(outputStream *st) const {
+print_on(st);
+print_heap_regions_on(st);
+}
+bool ShenandoahHeap::is_bitmap_slice_committed(ShenandoahHeapRegion* r, bool skip_self) {
+size_t slice = r->region_number() / _bitmap_regions_per_slice;
+size_t regions_from = _bitmap_regions_per_slice * slice;
+size_t regions_to   = MIN2(num_regions(), _bitmap_regions_per_slice * (slice + 1));
+for (size_t g = regions_from; g < regions_to; g++) {
+assert (g / _bitmap_regions_per_slice == slice, "same slice");
+if (skip_self && g == r->region_number()) continue;
+if (get_region(g)->is_committed()) {
+return true;
+}
+}
+return false;
+}
+bool ShenandoahHeap::commit_bitmap_slice(ShenandoahHeapRegion* r) {
+assert_heaplock_owned_by_current_thread();
+if (is_bitmap_slice_committed(r, true)) {
+// Some other region from the group is already committed, meaning the bitmap
+// slice is already committed, we exit right away.
+return true;
+}
+// Commit the bitmap slice:
+size_t slice = r->region_number() / _bitmap_regions_per_slice;
+size_t off = _bitmap_bytes_per_slice * slice;
+size_t len = _bitmap_bytes_per_slice;
+if (!os::commit_memory((char*)_bitmap_region.start() + off, len, false)) {
+return false;
+}
+return true;
+}
+bool ShenandoahHeap::uncommit_bitmap_slice(ShenandoahHeapRegion *r) {
+assert_heaplock_owned_by_current_thread();
+if (is_bitmap_slice_committed(r, true)) {
+// Some other region from the group is still committed, meaning the bitmap
+// slice is should stay committed, exit right away.
+return true;
+}
+// Uncommit the bitmap slice:
+size_t slice = r->region_number() / _bitmap_regions_per_slice;
+size_t off = _bitmap_bytes_per_slice * slice;
+size_t len = _bitmap_bytes_per_slice;
+if (!os::uncommit_memory((char*)_bitmap_region.start() + off, len)) {
+return false;
+}
+return true;
+}
+void ShenandoahHeap::safepoint_synchronize_begin() {
+if (ShenandoahSuspendibleWorkers || UseStringDeduplication) {
+SuspendibleThreadSet::synchronize();
+}
+}
+void ShenandoahHeap::safepoint_synchronize_end() {
+if (ShenandoahSuspendibleWorkers || UseStringDeduplication) {
+SuspendibleThreadSet::desynchronize();
+}
+}
+void ShenandoahHeap::vmop_entry_init_mark() {
+TraceCollectorStats tcs(monitoring_support()->stw_collection_counters());
+ShenandoahGCPhase total(ShenandoahPhaseTimings::total_pause_gross);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::init_mark_gross);
+try_inject_alloc_failure();
+VM_ShenandoahInitMark op;
+VMThread::execute(&op); // jump to entry_init_mark() under safepoint
+}
+void ShenandoahHeap::vmop_entry_final_mark() {
+TraceCollectorStats tcs(monitoring_support()->stw_collection_counters());
+ShenandoahGCPhase total(ShenandoahPhaseTimings::total_pause_gross);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::final_mark_gross);
+try_inject_alloc_failure();
+VM_ShenandoahFinalMarkStartEvac op;
+VMThread::execute(&op); // jump to entry_final_mark under safepoint
+}
+void ShenandoahHeap::vmop_entry_final_evac() {
+TraceCollectorStats tcs(monitoring_support()->stw_collection_counters());
+ShenandoahGCPhase total(ShenandoahPhaseTimings::total_pause_gross);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::final_evac_gross);
+VM_ShenandoahFinalEvac op;
+VMThread::execute(&op); // jump to entry_final_evac under safepoint
+}
+void ShenandoahHeap::vmop_entry_init_updaterefs() {
+TraceCollectorStats tcs(monitoring_support()->stw_collection_counters());
+ShenandoahGCPhase total(ShenandoahPhaseTimings::total_pause_gross);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::init_update_refs_gross);
+try_inject_alloc_failure();
+VM_ShenandoahInitUpdateRefs op;
+VMThread::execute(&op);
+}
+void ShenandoahHeap::vmop_entry_final_updaterefs() {
+TraceCollectorStats tcs(monitoring_support()->stw_collection_counters());
+ShenandoahGCPhase total(ShenandoahPhaseTimings::total_pause_gross);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::final_update_refs_gross);
+try_inject_alloc_failure();
+VM_ShenandoahFinalUpdateRefs op;
+VMThread::execute(&op);
+}
+void ShenandoahHeap::vmop_entry_init_traversal() {
+TraceCollectorStats tcs(monitoring_support()->stw_collection_counters());
+ShenandoahGCPhase total(ShenandoahPhaseTimings::total_pause_gross);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::init_traversal_gc_gross);
+try_inject_alloc_failure();
+VM_ShenandoahInitTraversalGC op;
+VMThread::execute(&op);
+}
+void ShenandoahHeap::vmop_entry_final_traversal() {
+TraceCollectorStats tcs(monitoring_support()->stw_collection_counters());
+ShenandoahGCPhase total(ShenandoahPhaseTimings::total_pause_gross);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::final_traversal_gc_gross);
+try_inject_alloc_failure();
+VM_ShenandoahFinalTraversalGC op;
+VMThread::execute(&op);
+}
+void ShenandoahHeap::vmop_entry_full(GCCause::Cause cause) {
+TraceCollectorStats tcs(monitoring_support()->full_stw_collection_counters());
+ShenandoahGCPhase total(ShenandoahPhaseTimings::total_pause_gross);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::full_gc_gross);
+try_inject_alloc_failure();
+VM_ShenandoahFullGC op(cause);
+VMThread::execute(&op);
+}
+void ShenandoahHeap::vmop_degenerated(ShenandoahDegenPoint point) {
+TraceCollectorStats tcs(monitoring_support()->full_stw_collection_counters());
+ShenandoahGCPhase total(ShenandoahPhaseTimings::total_pause_gross);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::degen_gc_gross);
+VM_ShenandoahDegeneratedGC degenerated_gc((int)point);
+VMThread::execute(&degenerated_gc);
+}
+void ShenandoahHeap::entry_init_mark() {
+ShenandoahGCPhase total_phase(ShenandoahPhaseTimings::total_pause);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::init_mark);
+const char* msg = init_mark_event_message();
+GCTraceTime(Info, gc) time(msg, gc_timer());
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_init_marking(),
+"init marking");
+op_init_mark();
+}
+void ShenandoahHeap::entry_final_mark() {
+ShenandoahGCPhase total_phase(ShenandoahPhaseTimings::total_pause);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::final_mark);
+const char* msg = final_mark_event_message();
+GCTraceTime(Info, gc) time(msg, gc_timer());
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_final_marking(),
+"final marking");
+op_final_mark();
+}
+void ShenandoahHeap::entry_final_evac() {
+ShenandoahGCPhase total_phase(ShenandoahPhaseTimings::total_pause);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::final_evac);
+static const char* msg = "Pause Final Evac";
+GCTraceTime(Info, gc) time(msg, gc_timer());
+EventMark em("%s", msg);
+op_final_evac();
+}
+void ShenandoahHeap::entry_init_updaterefs() {
+ShenandoahGCPhase total_phase(ShenandoahPhaseTimings::total_pause);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::init_update_refs);
+static const char* msg = "Pause Init Update Refs";
+GCTraceTime(Info, gc) time(msg, gc_timer());
+EventMark em("%s", msg);
+// No workers used in this phase, no setup required
+op_init_updaterefs();
+}
+void ShenandoahHeap::entry_final_updaterefs() {
+ShenandoahGCPhase total_phase(ShenandoahPhaseTimings::total_pause);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::final_update_refs);
+static const char* msg = "Pause Final Update Refs";
+GCTraceTime(Info, gc) time(msg, gc_timer());
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_final_update_ref(),
+"final reference update");
+op_final_updaterefs();
+}
+void ShenandoahHeap::entry_init_traversal() {
+ShenandoahGCPhase total_phase(ShenandoahPhaseTimings::total_pause);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::init_traversal_gc);
+static const char* msg = "Pause Init Traversal";
+GCTraceTime(Info, gc) time(msg, gc_timer());
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_stw_traversal(),
+"init traversal");
+op_init_traversal();
+}
+void ShenandoahHeap::entry_final_traversal() {
+ShenandoahGCPhase total_phase(ShenandoahPhaseTimings::total_pause);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::final_traversal_gc);
+static const char* msg = "Pause Final Traversal";
+GCTraceTime(Info, gc) time(msg, gc_timer());
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_stw_traversal(),
+"final traversal");
+op_final_traversal();
+}
+void ShenandoahHeap::entry_full(GCCause::Cause cause) {
+ShenandoahGCPhase total_phase(ShenandoahPhaseTimings::total_pause);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::full_gc);
+static const char* msg = "Pause Full";
+GCTraceTime(Info, gc) time(msg, gc_timer(), cause, true);
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_fullgc(),
+"full gc");
+op_full(cause);
+}
+void ShenandoahHeap::entry_degenerated(int point) {
+ShenandoahGCPhase total_phase(ShenandoahPhaseTimings::total_pause);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::degen_gc);
+ShenandoahDegenPoint dpoint = (ShenandoahDegenPoint)point;
+const char* msg = degen_event_message(dpoint);
+GCTraceTime(Info, gc) time(msg, NULL, GCCause::_no_gc, true);
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_stw_degenerated(),
+"stw degenerated gc");
+set_degenerated_gc_in_progress(true);
+op_degenerated(dpoint);
+set_degenerated_gc_in_progress(false);
+}
+void ShenandoahHeap::entry_mark() {
+TraceCollectorStats tcs(monitoring_support()->concurrent_collection_counters());
+const char* msg = conc_mark_event_message();
+GCTraceTime(Info, gc) time(msg, NULL, GCCause::_no_gc, true);
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_conc_marking(),
+"concurrent marking");
+try_inject_alloc_failure();
+op_mark();
+}
+void ShenandoahHeap::entry_evac() {
+ShenandoahGCPhase conc_evac_phase(ShenandoahPhaseTimings::conc_evac);
+TraceCollectorStats tcs(monitoring_support()->concurrent_collection_counters());
+static const char* msg = "Concurrent evacuation";
+GCTraceTime(Info, gc) time(msg, NULL, GCCause::_no_gc, true);
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_conc_evac(),
+"concurrent evacuation");
+try_inject_alloc_failure();
+op_conc_evac();
+}
+void ShenandoahHeap::entry_updaterefs() {
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::conc_update_refs);
+static const char* msg = "Concurrent update references";
+GCTraceTime(Info, gc) time(msg, NULL, GCCause::_no_gc, true);
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_conc_update_ref(),
+"concurrent reference update");
+try_inject_alloc_failure();
+op_updaterefs();
+}
+void ShenandoahHeap::entry_cleanup() {
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::conc_cleanup);
+static const char* msg = "Concurrent cleanup";
+GCTraceTime(Info, gc) time(msg, NULL, GCCause::_no_gc, true);
+EventMark em("%s", msg);
+// This phase does not use workers, no need for setup
+try_inject_alloc_failure();
+op_cleanup();
+}
+void ShenandoahHeap::entry_reset() {
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::conc_reset);
+static const char* msg = "Concurrent reset";
+GCTraceTime(Info, gc) time(msg, NULL, GCCause::_no_gc, true);
+EventMark em("%s", msg);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_conc_reset(),
+"concurrent reset");
+try_inject_alloc_failure();
+op_reset();
+}
+void ShenandoahHeap::entry_preclean() {
+if (ShenandoahPreclean && process_references()) {
+static const char* msg = "Concurrent precleaning";
+GCTraceTime(Info, gc) time(msg, NULL, GCCause::_no_gc, true);
+EventMark em("%s", msg);
+ShenandoahGCPhase conc_preclean(ShenandoahPhaseTimings::conc_preclean);
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_conc_preclean(),
+"concurrent preclean",
+/* check_workers = */ false);
+try_inject_alloc_failure();
+op_preclean();
+}
+}
+void ShenandoahHeap::entry_traversal() {
+static const char* msg = "Concurrent traversal";
+GCTraceTime(Info, gc) time(msg, NULL, GCCause::_no_gc, true);
+EventMark em("%s", msg);
+TraceCollectorStats tcs(monitoring_support()->concurrent_collection_counters());
+ShenandoahWorkerScope scope(workers(),
+ShenandoahWorkerPolicy::calc_workers_for_conc_traversal(),
+"concurrent traversal");
+try_inject_alloc_failure();
+op_traversal();
+}
+void ShenandoahHeap::entry_uncommit(double shrink_before) {
+static const char *msg = "Concurrent uncommit";
+GCTraceTime(Info, gc) time(msg, NULL, GCCause::_no_gc, true);
+EventMark em("%s", msg);
+ShenandoahGCPhase phase(ShenandoahPhaseTimings::conc_uncommit);
+op_uncommit(shrink_before);
+}
+void ShenandoahHeap::try_inject_alloc_failure() {
+if (ShenandoahAllocFailureALot && !cancelled_gc() && ((os::random() % 1000) > 950)) {
+_inject_alloc_failure.set();
+os::naked_short_sleep(1);
+if (cancelled_gc()) {
+log_info(gc)("Allocation failure was successfully injected");
+}
+}
+}
+bool ShenandoahHeap::should_inject_alloc_failure() {
+return _inject_alloc_failure.is_set() && _inject_alloc_failure.try_unset();
+}
+void ShenandoahHeap::initialize_serviceability() {
+_memory_pool = new ShenandoahMemoryPool(this);
+_cycle_memory_manager.add_pool(_memory_pool);
+_stw_memory_manager.add_pool(_memory_pool);
+}
+GrowableArray<GCMemoryManager*> ShenandoahHeap::memory_managers() {
+GrowableArray<GCMemoryManager*> memory_managers(2);
+memory_managers.append(&_cycle_memory_manager);
+memory_managers.append(&_stw_memory_manager);
+return memory_managers;
+}
+GrowableArray<MemoryPool*> ShenandoahHeap::memory_pools() {
+GrowableArray<MemoryPool*> memory_pools(1);
+memory_pools.append(_memory_pool);
+return memory_pools;
+}
+void ShenandoahHeap::enter_evacuation() {
+_oom_evac_handler.enter_evacuation();
+}
+void ShenandoahHeap::leave_evacuation() {
+_oom_evac_handler.leave_evacuation();
+}
+ShenandoahRegionIterator::ShenandoahRegionIterator() :
+_heap(ShenandoahHeap::heap()),
+_index(0) {}
+ShenandoahRegionIterator::ShenandoahRegionIterator(ShenandoahHeap* heap) :
+_heap(heap),
+_index(0) {}
+void ShenandoahRegionIterator::reset() {
+_index = 0;
+}
+bool ShenandoahRegionIterator::has_next() const {
+return _index < _heap->num_regions();
+}
+char ShenandoahHeap::gc_state() const {
+return _gc_state.raw_value();
+}
+void ShenandoahHeap::deduplicate_string(oop str) {
+assert(java_lang_String::is_instance(str), "invariant");
+if (ShenandoahStringDedup::is_enabled()) {
+ShenandoahStringDedup::deduplicate(str);
+}
+}
+const char* ShenandoahHeap::init_mark_event_message() const {
+bool update_refs = has_forwarded_objects();
+bool proc_refs = process_references();
+bool unload_cls = unload_classes();
+if (update_refs && proc_refs && unload_cls) {
+return "Pause Init Mark (update refs) (process weakrefs) (unload classes)";
+} else if (update_refs && proc_refs) {
+return "Pause Init Mark (update refs) (process weakrefs)";
+} else if (update_refs && unload_cls) {
+return "Pause Init Mark (update refs) (unload classes)";
+} else if (proc_refs && unload_cls) {
+return "Pause Init Mark (process weakrefs) (unload classes)";
+} else if (update_refs) {
+return "Pause Init Mark (update refs)";
+} else if (proc_refs) {
+return "Pause Init Mark (process weakrefs)";
+} else if (unload_cls) {
+return "Pause Init Mark (unload classes)";
+} else {
+return "Pause Init Mark";
+}
+}
+const char* ShenandoahHeap::final_mark_event_message() const {
+bool update_refs = has_forwarded_objects();
+bool proc_refs = process_references();
+bool unload_cls = unload_classes();
+if (update_refs && proc_refs && unload_cls) {
+return "Pause Final Mark (update refs) (process weakrefs) (unload classes)";
+} else if (update_refs && proc_refs) {
+return "Pause Final Mark (update refs) (process weakrefs)";
+} else if (update_refs && unload_cls) {
+return "Pause Final Mark (update refs) (unload classes)";
+} else if (proc_refs && unload_cls) {
+return "Pause Final Mark (process weakrefs) (unload classes)";
+} else if (update_refs) {
+return "Pause Final Mark (update refs)";
+} else if (proc_refs) {
+return "Pause Final Mark (process weakrefs)";
+} else if (unload_cls) {
+return "Pause Final Mark (unload classes)";
+} else {
+return "Pause Final Mark";
+}
+}
+const char* ShenandoahHeap::conc_mark_event_message() const {
+bool update_refs = has_forwarded_objects();
+bool proc_refs = process_references();
+bool unload_cls = unload_classes();
+if (update_refs && proc_refs && unload_cls) {
+return "Concurrent marking (update refs) (process weakrefs) (unload classes)";
+} else if (update_refs && proc_refs) {
+return "Concurrent marking (update refs) (process weakrefs)";
+} else if (update_refs && unload_cls) {
+return "Concurrent marking (update refs) (unload classes)";
+} else if (proc_refs && unload_cls) {
+return "Concurrent marking (process weakrefs) (unload classes)";
+} else if (update_refs) {
+return "Concurrent marking (update refs)";
+} else if (proc_refs) {
+return "Concurrent marking (process weakrefs)";
+} else if (unload_cls) {
+return "Concurrent marking (unload classes)";
+} else {
+return "Concurrent marking";
+}
+}
+const char* ShenandoahHeap::degen_event_message(ShenandoahDegenPoint point) const {
+switch (point) {
+case _degenerated_unset:
+return "Pause Degenerated GC (<UNSET>)";
+case _degenerated_traversal:
+return "Pause Degenerated GC (Traversal)";
+case _degenerated_outside_cycle:
+return "Pause Degenerated GC (Outside of Cycle)";
+case _degenerated_mark:
+return "Pause Degenerated GC (Mark)";
+case _degenerated_evac:
+return "Pause Degenerated GC (Evacuation)";
+case _degenerated_updaterefs:
+return "Pause Degenerated GC (Update Refs)";
+default:
+ShouldNotReachHere();
+return "ERROR";
+}
+}
+jushort* ShenandoahHeap::get_liveness_cache(uint worker_id) {
+#ifdef ASSERT
+assert(worker_id < _max_workers, "sanity");
+for (uint i = 0; i < num_regions(); i++) {
+assert(_liveness_cache[worker_id][i] == 0, "liveness cache should be empty");
+}
+#endif
+return _liveness_cache[worker_id];
+}
+void ShenandoahHeap::flush_liveness_cache(uint worker_id) {
+assert(worker_id < _max_workers, "sanity");
+jushort* ld = _liveness_cache[worker_id];
+for (uint i = 0; i < num_regions(); i++) {
+ShenandoahHeapRegion* r = get_region(i);
+jushort live = ld[i];
+if (live > 0) {
+r->increase_live_data_gc_words(live);
+ld[i] = 0;
+}
+}
+}
+size_t ShenandoahHeap::obj_size(oop obj) const {
+return CollectedHeap::obj_size(obj) + ShenandoahBrooksPointer::word_size();
+}
+ptrdiff_t ShenandoahHeap::cell_header_size() const {
+return ShenandoahBrooksPointer::byte_size();
+}
+BoolObjectClosure* ShenandoahIsAliveSelector::is_alive_closure() {
+return ShenandoahHeap::heap()->has_forwarded_objects() ? reinterpret_cast<BoolObjectClosure*>(&_fwd_alive_cl)
+: reinterpret_cast<BoolObjectClosure*>(&_alive_cl);
+}

changeset 52925	9c18c9d839d3
child 53276	72fdf46a274e