--- /dev/null 2014-07-16 10:04:12.054455181 +0200 +++ new/src/share/vm/gc_implementation/g1/g1ParScanThreadState.hpp 2014-07-16 15:29:35.714202775 +0200 @@ -0,0 +1,292 @@ +/* + * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * 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. + * + */ + +#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1PARSCANTHREADSTATE_HPP +#define SHARE_VM_GC_IMPLEMENTATION_G1_G1PARSCANTHREADSTATE_HPP + +#include "gc_implementation/g1/dirtyCardQueue.hpp" +#include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp" +#include "gc_implementation/g1/g1CollectedHeap.hpp" +#include "gc_implementation/g1/g1CollectorPolicy.hpp" +#include "gc_implementation/g1/g1OopClosures.hpp" +#include "gc_implementation/g1/g1RemSet.hpp" +#include "gc_implementation/shared/ageTable.hpp" +#include "memory/allocation.hpp" +#include "oops/oop.hpp" + +class HeapRegion; +class outputStream; + +class G1ParScanThreadState : public StackObj { +protected: + G1CollectedHeap* _g1h; + RefToScanQueue* _refs; + DirtyCardQueue _dcq; + G1SATBCardTableModRefBS* _ct_bs; + G1RemSet* _g1_rem; + + G1ParGCAllocBuffer _surviving_alloc_buffer; + G1ParGCAllocBuffer _tenured_alloc_buffer; + G1ParGCAllocBuffer* _alloc_buffers[GCAllocPurposeCount]; + ageTable _age_table; + + G1ParScanClosure _scanner; + + size_t _alloc_buffer_waste; + size_t _undo_waste; + + OopsInHeapRegionClosure* _evac_failure_cl; + + int _hash_seed; + uint _queue_num; + + size_t _term_attempts; + + double _start; + double _start_strong_roots; + double _strong_roots_time; + double _start_term; + double _term_time; + + // Map from young-age-index (0 == not young, 1 is youngest) to + // surviving words. base is what we get back from the malloc call + size_t* _surviving_young_words_base; + // this points into the array, as we use the first few entries for padding + size_t* _surviving_young_words; + +#define PADDING_ELEM_NUM (DEFAULT_CACHE_LINE_SIZE / sizeof(size_t)) + + void add_to_alloc_buffer_waste(size_t waste) { _alloc_buffer_waste += waste; } + + void add_to_undo_waste(size_t waste) { _undo_waste += waste; } + + DirtyCardQueue& dirty_card_queue() { return _dcq; } + G1SATBCardTableModRefBS* ctbs() { return _ct_bs; } + + template inline void immediate_rs_update(HeapRegion* from, T* p, int tid); + + template void deferred_rs_update(HeapRegion* from, T* p, int tid) { + // If the new value of the field points to the same region or + // is the to-space, we don't need to include it in the Rset updates. + if (!from->is_in_reserved(oopDesc::load_decode_heap_oop(p)) && !from->is_survivor()) { + size_t card_index = ctbs()->index_for(p); + // If the card hasn't been added to the buffer, do it. + if (ctbs()->mark_card_deferred(card_index)) { + dirty_card_queue().enqueue((jbyte*)ctbs()->byte_for_index(card_index)); + } + } + } + +public: + G1ParScanThreadState(G1CollectedHeap* g1h, uint queue_num, ReferenceProcessor* rp); + ~G1ParScanThreadState() { + retire_alloc_buffers(); + FREE_C_HEAP_ARRAY(size_t, _surviving_young_words_base, mtGC); + } + + RefToScanQueue* refs() { return _refs; } + ageTable* age_table() { return &_age_table; } + + G1ParGCAllocBuffer* alloc_buffer(GCAllocPurpose purpose) { + return _alloc_buffers[purpose]; + } + + size_t alloc_buffer_waste() const { return _alloc_buffer_waste; } + size_t undo_waste() const { return _undo_waste; } + +#ifdef ASSERT + bool verify_ref(narrowOop* ref) const; + bool verify_ref(oop* ref) const; + bool verify_task(StarTask ref) const; +#endif // ASSERT + + template void push_on_queue(T* ref) { + assert(verify_ref(ref), "sanity"); + refs()->push(ref); + } + + template inline void update_rs(HeapRegion* from, T* p, int tid); + + HeapWord* allocate_slow(GCAllocPurpose purpose, size_t word_sz) { + HeapWord* obj = NULL; + size_t gclab_word_size = _g1h->desired_plab_sz(purpose); + if (word_sz * 100 < gclab_word_size * ParallelGCBufferWastePct) { + G1ParGCAllocBuffer* alloc_buf = alloc_buffer(purpose); + add_to_alloc_buffer_waste(alloc_buf->words_remaining()); + alloc_buf->retire(false /* end_of_gc */, false /* retain */); + + HeapWord* buf = _g1h->par_allocate_during_gc(purpose, gclab_word_size); + if (buf == NULL) return NULL; // Let caller handle allocation failure. + // Otherwise. + alloc_buf->set_word_size(gclab_word_size); + alloc_buf->set_buf(buf); + + obj = alloc_buf->allocate(word_sz); + assert(obj != NULL, "buffer was definitely big enough..."); + } else { + obj = _g1h->par_allocate_during_gc(purpose, word_sz); + } + return obj; + } + + HeapWord* allocate(GCAllocPurpose purpose, size_t word_sz) { + HeapWord* obj = alloc_buffer(purpose)->allocate(word_sz); + if (obj != NULL) return obj; + return allocate_slow(purpose, word_sz); + } + + void undo_allocation(GCAllocPurpose purpose, HeapWord* obj, size_t word_sz) { + if (alloc_buffer(purpose)->contains(obj)) { + assert(alloc_buffer(purpose)->contains(obj + word_sz - 1), + "should contain whole object"); + alloc_buffer(purpose)->undo_allocation(obj, word_sz); + } else { + CollectedHeap::fill_with_object(obj, word_sz); + add_to_undo_waste(word_sz); + } + } + + void set_evac_failure_closure(OopsInHeapRegionClosure* evac_failure_cl) { + _evac_failure_cl = evac_failure_cl; + } + OopsInHeapRegionClosure* evac_failure_closure() { + return _evac_failure_cl; + } + + int* hash_seed() { return &_hash_seed; } + uint queue_num() { return _queue_num; } + + size_t term_attempts() const { return _term_attempts; } + void note_term_attempt() { _term_attempts++; } + + void start_strong_roots() { + _start_strong_roots = os::elapsedTime(); + } + void end_strong_roots() { + _strong_roots_time += (os::elapsedTime() - _start_strong_roots); + } + double strong_roots_time() const { return _strong_roots_time; } + + void start_term_time() { + note_term_attempt(); + _start_term = os::elapsedTime(); + } + void end_term_time() { + _term_time += (os::elapsedTime() - _start_term); + } + double term_time() const { return _term_time; } + + double elapsed_time() const { + return os::elapsedTime() - _start; + } + + static void + print_termination_stats_hdr(outputStream* const st = gclog_or_tty); + void + print_termination_stats(int i, outputStream* const st = gclog_or_tty) const; + + size_t* surviving_young_words() { + // We add on to hide entry 0 which accumulates surviving words for + // age -1 regions (i.e. non-young ones) + return _surviving_young_words; + } + + private: + void retire_alloc_buffers() { + for (int ap = 0; ap < GCAllocPurposeCount; ++ap) { + size_t waste = _alloc_buffers[ap]->words_remaining(); + add_to_alloc_buffer_waste(waste); + _alloc_buffers[ap]->flush_stats_and_retire(_g1h->stats_for_purpose((GCAllocPurpose)ap), + true /* end_of_gc */, + false /* retain */); + } + } + + #define G1_PARTIAL_ARRAY_MASK 0x2 + + inline bool has_partial_array_mask(oop* ref) const { + return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK; + } + + // We never encode partial array oops as narrowOop*, so return false immediately. + // This allows the compiler to create optimized code when popping references from + // the work queue. + inline bool has_partial_array_mask(narrowOop* ref) const { + assert(((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) != G1_PARTIAL_ARRAY_MASK, "Partial array oop reference encoded as narrowOop*"); + return false; + } + + // Only implement set_partial_array_mask() for regular oops, not for narrowOops. + // We always encode partial arrays as regular oop, to allow the + // specialization for has_partial_array_mask() for narrowOops above. + // This means that unintentional use of this method with narrowOops are caught + // by the compiler. + inline oop* set_partial_array_mask(oop obj) const { + assert(((uintptr_t)(void *)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!"); + return (oop*) ((uintptr_t)(void *)obj | G1_PARTIAL_ARRAY_MASK); + } + + inline oop clear_partial_array_mask(oop* ref) const { + return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK); + } + + inline void do_oop_partial_array(oop* p); + + // This method is applied to the fields of the objects that have just been copied. + template void do_oop_evac(T* p, HeapRegion* from) { + assert(!oopDesc::is_null(oopDesc::load_decode_heap_oop(p)), + "Reference should not be NULL here as such are never pushed to the task queue."); + oop obj = oopDesc::load_decode_heap_oop_not_null(p); + + // Although we never intentionally push references outside of the collection + // set, due to (benign) races in the claim mechanism during RSet scanning more + // than one thread might claim the same card. So the same card may be + // processed multiple times. So redo this check. + if (_g1h->in_cset_fast_test(obj)) { + oop forwardee; + if (obj->is_forwarded()) { + forwardee = obj->forwardee(); + } else { + forwardee = copy_to_survivor_space(obj); + } + assert(forwardee != NULL, "forwardee should not be NULL"); + oopDesc::encode_store_heap_oop(p, forwardee); + } + + assert(obj != NULL, "Must be"); + update_rs(from, p, queue_num()); + } +public: + + oop copy_to_survivor_space(oop const obj); + + template inline void deal_with_reference(T* ref_to_scan); + + inline void deal_with_reference(StarTask ref); + +public: + void trim_queue(); +}; + +#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1PARSCANTHREADSTATE_HPP