Mercurial > hg > truffle
view src/share/vm/gc_implementation/parNew/parNewGeneration.hpp @ 6233:d5bc62fcfac7
Merge
author | zgu |
---|---|
date | Thu, 19 Jul 2012 09:10:12 -0400 |
parents | d2a62e0f25eb |
children | aaf61e68b255 |
line wrap: on
line source
/* * Copyright (c) 2001, 2010, 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_PARNEW_PARNEWGENERATION_HPP #define SHARE_VM_GC_IMPLEMENTATION_PARNEW_PARNEWGENERATION_HPP #include "gc_implementation/parNew/parGCAllocBuffer.hpp" #include "memory/defNewGeneration.hpp" #include "utilities/taskqueue.hpp" class ChunkArray; class ParScanWithoutBarrierClosure; class ParScanWithBarrierClosure; class ParRootScanWithoutBarrierClosure; class ParRootScanWithBarrierTwoGensClosure; class ParEvacuateFollowersClosure; // It would be better if these types could be kept local to the .cpp file, // but they must be here to allow ParScanClosure::do_oop_work to be defined // in genOopClosures.inline.hpp. typedef Padded<OopTaskQueue> ObjToScanQueue; typedef GenericTaskQueueSet<ObjToScanQueue, mtGC> ObjToScanQueueSet; class ParKeepAliveClosure: public DefNewGeneration::KeepAliveClosure { private: ParScanWeakRefClosure* _par_cl; protected: template <class T> void do_oop_work(T* p); public: ParKeepAliveClosure(ParScanWeakRefClosure* cl); virtual void do_oop(oop* p); virtual void do_oop(narrowOop* p); }; // The state needed by thread performing parallel young-gen collection. class ParScanThreadState { friend class ParScanThreadStateSet; private: ObjToScanQueue *_work_queue; Stack<oop, mtGC>* const _overflow_stack; ParGCAllocBuffer _to_space_alloc_buffer; ParScanWithoutBarrierClosure _to_space_closure; // scan_without_gc_barrier ParScanWithBarrierClosure _old_gen_closure; // scan_with_gc_barrier ParRootScanWithoutBarrierClosure _to_space_root_closure; // scan_root_without_gc_barrier // One of these two will be passed to process_strong_roots, which will // set its generation. The first is for two-gen configs where the // old gen collects the perm gen; the second is for arbitrary configs. // The second isn't used right now (it used to be used for the train, an // incremental collector) but the declaration has been left as a reminder. ParRootScanWithBarrierTwoGensClosure _older_gen_closure; // This closure will always be bound to the old gen; it will be used // in evacuate_followers. ParRootScanWithBarrierTwoGensClosure _old_gen_root_closure; // scan_old_root_with_gc_barrier ParEvacuateFollowersClosure _evacuate_followers; DefNewGeneration::IsAliveClosure _is_alive_closure; ParScanWeakRefClosure _scan_weak_ref_closure; ParKeepAliveClosure _keep_alive_closure; Space* _to_space; Space* to_space() { return _to_space; } ParNewGeneration* _young_gen; ParNewGeneration* young_gen() const { return _young_gen; } Generation* _old_gen; Generation* old_gen() { return _old_gen; } HeapWord *_young_old_boundary; int _hash_seed; int _thread_num; ageTable _ageTable; bool _to_space_full; #if TASKQUEUE_STATS size_t _term_attempts; size_t _overflow_refills; size_t _overflow_refill_objs; #endif // TASKQUEUE_STATS // Stats for promotion failure size_t _promotion_failure_size; // Timing numbers. double _start; double _start_strong_roots; double _strong_roots_time; double _start_term; double _term_time; // Helper for trim_queues. Scans subset of an array and makes // remainder available for work stealing. void scan_partial_array_and_push_remainder(oop obj); // In support of CMS' parallel rescan of survivor space. ChunkArray* _survivor_chunk_array; ChunkArray* survivor_chunk_array() { return _survivor_chunk_array; } void record_survivor_plab(HeapWord* plab_start, size_t plab_word_size); ParScanThreadState(Space* to_space_, ParNewGeneration* gen_, Generation* old_gen_, int thread_num_, ObjToScanQueueSet* work_queue_set_, Stack<oop, mtGC>* overflow_stacks_, size_t desired_plab_sz_, ParallelTaskTerminator& term_); public: ageTable* age_table() {return &_ageTable;} ObjToScanQueue* work_queue() { return _work_queue; } ParGCAllocBuffer* to_space_alloc_buffer() { return &_to_space_alloc_buffer; } ParEvacuateFollowersClosure& evacuate_followers_closure() { return _evacuate_followers; } DefNewGeneration::IsAliveClosure& is_alive_closure() { return _is_alive_closure; } ParScanWeakRefClosure& scan_weak_ref_closure() { return _scan_weak_ref_closure; } ParKeepAliveClosure& keep_alive_closure() { return _keep_alive_closure; } ParScanClosure& older_gen_closure() { return _older_gen_closure; } ParRootScanWithoutBarrierClosure& to_space_root_closure() { return _to_space_root_closure; }; // Decrease queue size below "max_size". void trim_queues(int max_size); // Private overflow stack usage Stack<oop, mtGC>* overflow_stack() { return _overflow_stack; } bool take_from_overflow_stack(); void push_on_overflow_stack(oop p); // Is new_obj a candidate for scan_partial_array_and_push_remainder method. inline bool should_be_partially_scanned(oop new_obj, oop old_obj) const; int* hash_seed() { return &_hash_seed; } int thread_num() { return _thread_num; } // Allocate a to-space block of size "sz", or else return NULL. HeapWord* alloc_in_to_space_slow(size_t word_sz); HeapWord* alloc_in_to_space(size_t word_sz) { HeapWord* obj = to_space_alloc_buffer()->allocate(word_sz); if (obj != NULL) return obj; else return alloc_in_to_space_slow(word_sz); } HeapWord* young_old_boundary() { return _young_old_boundary; } void set_young_old_boundary(HeapWord *boundary) { _young_old_boundary = boundary; } // Undo the most recent allocation ("obj", of "word_sz"). void undo_alloc_in_to_space(HeapWord* obj, size_t word_sz); // Promotion failure stats size_t promotion_failure_size() { return promotion_failure_size(); } void log_promotion_failure(size_t sz) { if (_promotion_failure_size == 0) { _promotion_failure_size = sz; } } void print_and_clear_promotion_failure_size(); #if TASKQUEUE_STATS TaskQueueStats & taskqueue_stats() const { return _work_queue->stats; } size_t term_attempts() const { return _term_attempts; } size_t overflow_refills() const { return _overflow_refills; } size_t overflow_refill_objs() const { return _overflow_refill_objs; } void note_term_attempt() { ++_term_attempts; } void note_overflow_refill(size_t objs) { ++_overflow_refills; _overflow_refill_objs += objs; } void reset_stats(); #endif // TASKQUEUE_STATS 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() { TASKQUEUE_STATS_ONLY(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; } }; class ParNewGenTask: public AbstractGangTask { private: ParNewGeneration* _gen; Generation* _next_gen; HeapWord* _young_old_boundary; class ParScanThreadStateSet* _state_set; public: ParNewGenTask(ParNewGeneration* gen, Generation* next_gen, HeapWord* young_old_boundary, ParScanThreadStateSet* state_set); HeapWord* young_old_boundary() { return _young_old_boundary; } void work(uint worker_id); // Reset the terminator in ParScanThreadStateSet for // "active_workers" threads. virtual void set_for_termination(int active_workers); }; class KeepAliveClosure: public DefNewGeneration::KeepAliveClosure { protected: template <class T> void do_oop_work(T* p); public: KeepAliveClosure(ScanWeakRefClosure* cl); virtual void do_oop(oop* p); virtual void do_oop(narrowOop* p); }; class EvacuateFollowersClosureGeneral: public VoidClosure { private: GenCollectedHeap* _gch; int _level; OopsInGenClosure* _scan_cur_or_nonheap; OopsInGenClosure* _scan_older; public: EvacuateFollowersClosureGeneral(GenCollectedHeap* gch, int level, OopsInGenClosure* cur, OopsInGenClosure* older); virtual void do_void(); }; // Closure for scanning ParNewGeneration. // Same as ScanClosure, except does parallel GC barrier. class ScanClosureWithParBarrier: public ScanClosure { protected: template <class T> void do_oop_work(T* p); public: ScanClosureWithParBarrier(ParNewGeneration* g, bool gc_barrier); virtual void do_oop(oop* p); virtual void do_oop(narrowOop* p); }; // Implements AbstractRefProcTaskExecutor for ParNew. class ParNewRefProcTaskExecutor: public AbstractRefProcTaskExecutor { private: ParNewGeneration& _generation; ParScanThreadStateSet& _state_set; public: ParNewRefProcTaskExecutor(ParNewGeneration& generation, ParScanThreadStateSet& state_set) : _generation(generation), _state_set(state_set) { } // Executes a task using worker threads. virtual void execute(ProcessTask& task); virtual void execute(EnqueueTask& task); // Switch to single threaded mode. virtual void set_single_threaded_mode(); }; // A Generation that does parallel young-gen collection. class ParNewGeneration: public DefNewGeneration { friend class ParNewGenTask; friend class ParNewRefProcTask; friend class ParNewRefProcTaskExecutor; friend class ParScanThreadStateSet; friend class ParEvacuateFollowersClosure; private: // The per-worker-thread work queues ObjToScanQueueSet* _task_queues; // Per-worker-thread local overflow stacks Stack<oop, mtGC>* _overflow_stacks; // Desired size of survivor space plab's PLABStats _plab_stats; // A list of from-space images of to-be-scanned objects, threaded through // klass-pointers (klass information already copied to the forwarded // image.) Manipulated with CAS. oop _overflow_list; NOT_PRODUCT(ssize_t _num_par_pushes;) // If true, older generation does not support promotion undo, so avoid. static bool _avoid_promotion_undo; // This closure is used by the reference processor to filter out // references to live referent. DefNewGeneration::IsAliveClosure _is_alive_closure; static oop real_forwardee_slow(oop obj); static void waste_some_time(); // Preserve the mark of "obj", if necessary, in preparation for its mark // word being overwritten with a self-forwarding-pointer. void preserve_mark_if_necessary(oop obj, markOop m); protected: bool _survivor_overflow; bool avoid_promotion_undo() { return _avoid_promotion_undo; } void set_avoid_promotion_undo(bool v) { _avoid_promotion_undo = v; } bool survivor_overflow() { return _survivor_overflow; } void set_survivor_overflow(bool v) { _survivor_overflow = v; } // Adjust the tenuring threshold. See the implementation for // the details of the policy. virtual void adjust_desired_tenuring_threshold(); public: ParNewGeneration(ReservedSpace rs, size_t initial_byte_size, int level); ~ParNewGeneration() { for (uint i = 0; i < ParallelGCThreads; i++) delete _task_queues->queue(i); delete _task_queues; } static bool in_use(); virtual void ref_processor_init(); virtual Generation::Name kind() { return Generation::ParNew; } virtual const char* name() const; virtual const char* short_name() const { return "ParNew"; } // override virtual bool refs_discovery_is_mt() const { assert(UseParNewGC, "ParNewGeneration only when UseParNewGC"); return ParallelGCThreads > 1; } // Make the collection virtual. virtual void collect(bool full, bool clear_all_soft_refs, size_t size, bool is_tlab); // This needs to be visible to the closure function. // "obj" is the object to be copied, "m" is a recent value of its mark // that must not contain a forwarding pointer (though one might be // inserted in "obj"s mark word by a parallel thread). inline oop copy_to_survivor_space(ParScanThreadState* par_scan_state, oop obj, size_t obj_sz, markOop m) { if (_avoid_promotion_undo) { return copy_to_survivor_space_avoiding_promotion_undo(par_scan_state, obj, obj_sz, m); } return copy_to_survivor_space_with_undo(par_scan_state, obj, obj_sz, m); } oop copy_to_survivor_space_avoiding_promotion_undo(ParScanThreadState* par_scan_state, oop obj, size_t obj_sz, markOop m); oop copy_to_survivor_space_with_undo(ParScanThreadState* par_scan_state, oop obj, size_t obj_sz, markOop m); // in support of testing overflow code NOT_PRODUCT(int _overflow_counter;) NOT_PRODUCT(bool should_simulate_overflow();) // Accessor for overflow list oop overflow_list() { return _overflow_list; } // Push the given (from-space) object on the global overflow list. void push_on_overflow_list(oop from_space_obj, ParScanThreadState* par_scan_state); // If the global overflow list is non-empty, move some tasks from it // onto "work_q" (which need not be empty). No more than 1/4 of the // available space on "work_q" is used. bool take_from_overflow_list(ParScanThreadState* par_scan_state); bool take_from_overflow_list_work(ParScanThreadState* par_scan_state); // The task queues to be used by parallel GC threads. ObjToScanQueueSet* task_queues() { return _task_queues; } PLABStats* plab_stats() { return &_plab_stats; } size_t desired_plab_sz() { return _plab_stats.desired_plab_sz(); } static oop real_forwardee(oop obj); DEBUG_ONLY(static bool is_legal_forward_ptr(oop p);) }; #endif // SHARE_VM_GC_IMPLEMENTATION_PARNEW_PARNEWGENERATION_HPP