| /* |
| * Copyright (c) 2001, 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 |
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| * questions. |
| * |
| */ |
| |
| #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1REMSET_HPP |
| #define SHARE_VM_GC_IMPLEMENTATION_G1_G1REMSET_HPP |
| |
| #include "gc_implementation/g1/g1RemSetSummary.hpp" |
| |
| // A G1RemSet provides ways of iterating over pointers into a selected |
| // collection set. |
| |
| class G1CollectedHeap; |
| class CardTableModRefBarrierSet; |
| class ConcurrentG1Refine; |
| class G1ParPushHeapRSClosure; |
| |
| // A G1RemSet in which each heap region has a rem set that records the |
| // external heap references into it. Uses a mod ref bs to track updates, |
| // so that they can be used to update the individual region remsets. |
| |
| class G1RemSet: public CHeapObj<mtGC> { |
| private: |
| G1RemSetSummary _prev_period_summary; |
| protected: |
| G1CollectedHeap* _g1; |
| size_t _conc_refine_cards; |
| uint n_workers(); |
| |
| protected: |
| enum SomePrivateConstants { |
| UpdateRStoMergeSync = 0, |
| MergeRStoDoDirtySync = 1, |
| DoDirtySync = 2, |
| LastSync = 3, |
| |
| SeqTask = 0, |
| NumSeqTasks = 1 |
| }; |
| |
| CardTableModRefBS* _ct_bs; |
| G1CollectorPolicy* _g1p; |
| |
| ConcurrentG1Refine* _cg1r; |
| |
| size_t* _cards_scanned; |
| size_t _total_cards_scanned; |
| |
| // Used for caching the closure that is responsible for scanning |
| // references into the collection set. |
| G1ParPushHeapRSClosure** _cset_rs_update_cl; |
| |
| // Print the given summary info |
| virtual void print_summary_info(G1RemSetSummary * summary, const char * header = NULL); |
| public: |
| // This is called to reset dual hash tables after the gc pause |
| // is finished and the initial hash table is no longer being |
| // scanned. |
| void cleanupHRRS(); |
| |
| G1RemSet(G1CollectedHeap* g1, CardTableModRefBS* ct_bs); |
| ~G1RemSet(); |
| |
| // Invoke "blk->do_oop" on all pointers into the collection set |
| // from objects in regions outside the collection set (having |
| // invoked "blk->set_region" to set the "from" region correctly |
| // beforehand.) |
| // |
| // Invoke code_root_cl->do_code_blob on the unmarked nmethods |
| // on the strong code roots list for each region in the |
| // collection set. |
| // |
| // The "worker_i" param is for the parallel case where the id |
| // of the worker thread calling this function can be helpful in |
| // partitioning the work to be done. It should be the same as |
| // the "i" passed to the calling thread's work(i) function. |
| // In the sequential case this param will be ignored. |
| void oops_into_collection_set_do(G1ParPushHeapRSClosure* blk, |
| CodeBlobClosure* code_root_cl, |
| uint worker_i); |
| |
| // Prepare for and cleanup after an oops_into_collection_set_do |
| // call. Must call each of these once before and after (in sequential |
| // code) any threads call oops_into_collection_set_do. (This offers an |
| // opportunity to sequential setup and teardown of structures needed by a |
| // parallel iteration over the CS's RS.) |
| void prepare_for_oops_into_collection_set_do(); |
| void cleanup_after_oops_into_collection_set_do(); |
| |
| void scanRS(G1ParPushHeapRSClosure* oc, |
| CodeBlobClosure* code_root_cl, |
| uint worker_i); |
| |
| void updateRS(DirtyCardQueue* into_cset_dcq, uint worker_i); |
| |
| CardTableModRefBS* ct_bs() { return _ct_bs; } |
| size_t cardsScanned() { return _total_cards_scanned; } |
| |
| // Record, if necessary, the fact that *p (where "p" is in region "from", |
| // which is required to be non-NULL) has changed to a new non-NULL value. |
| template <class T> void write_ref(HeapRegion* from, T* p); |
| template <class T> void par_write_ref(HeapRegion* from, T* p, int tid); |
| |
| // Requires "region_bm" and "card_bm" to be bitmaps with 1 bit per region |
| // or card, respectively, such that a region or card with a corresponding |
| // 0 bit contains no part of any live object. Eliminates any remembered |
| // set entries that correspond to dead heap ranges. |
| void scrub(BitMap* region_bm, BitMap* card_bm); |
| |
| // Like the above, but assumes is called in parallel: "worker_num" is the |
| // parallel thread id of the current thread, and "claim_val" is the |
| // value that should be used to claim heap regions. |
| void scrub_par(BitMap* region_bm, BitMap* card_bm, |
| uint worker_num, int claim_val); |
| |
| // Refine the card corresponding to "card_ptr". |
| // If check_for_refs_into_cset is true, a true result is returned |
| // if the given card contains oops that have references into the |
| // current collection set. |
| virtual bool refine_card(jbyte* card_ptr, |
| uint worker_i, |
| bool check_for_refs_into_cset); |
| |
| // Print accumulated summary info from the start of the VM. |
| virtual void print_summary_info(); |
| |
| // Print accumulated summary info from the last time called. |
| virtual void print_periodic_summary_info(const char* header); |
| |
| // Prepare remembered set for verification. |
| virtual void prepare_for_verify(); |
| |
| size_t conc_refine_cards() const { |
| return _conc_refine_cards; |
| } |
| }; |
| |
| class CountNonCleanMemRegionClosure: public MemRegionClosure { |
| G1CollectedHeap* _g1; |
| int _n; |
| HeapWord* _start_first; |
| public: |
| CountNonCleanMemRegionClosure(G1CollectedHeap* g1) : |
| _g1(g1), _n(0), _start_first(NULL) |
| {} |
| void do_MemRegion(MemRegion mr); |
| int n() { return _n; }; |
| HeapWord* start_first() { return _start_first; } |
| }; |
| |
| class UpdateRSOopClosure: public ExtendedOopClosure { |
| HeapRegion* _from; |
| G1RemSet* _rs; |
| uint _worker_i; |
| |
| template <class T> void do_oop_work(T* p); |
| |
| public: |
| UpdateRSOopClosure(G1RemSet* rs, uint worker_i = 0) : |
| _from(NULL), _rs(rs), _worker_i(worker_i) |
| {} |
| |
| void set_from(HeapRegion* from) { |
| assert(from != NULL, "from region must be non-NULL"); |
| _from = from; |
| } |
| |
| virtual void do_oop(narrowOop* p) { do_oop_work(p); } |
| virtual void do_oop(oop* p) { do_oop_work(p); } |
| |
| // Override: this closure is idempotent. |
| // bool idempotent() { return true; } |
| bool apply_to_weak_ref_discovered_field() { return true; } |
| }; |
| |
| #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1REMSET_HPP |