1 /*
  2  * Copyright (c) 2017, 2023, Oracle and/or its affiliates. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  *
 23  */
 24 
 25 #include "precompiled.hpp"
 26 #include "classfile/classLoaderData.hpp"
 27 #include "classfile/classLoaderDataGraph.hpp"
 28 #include "gc/g1/g1CollectedHeap.hpp"
 29 #include "gc/g1/g1ConcurrentMarkBitMap.inline.hpp"
 30 #include "gc/g1/g1FullCollector.inline.hpp"
 31 #include "gc/g1/g1FullGCAdjustTask.hpp"
 32 #include "gc/g1/g1FullGCCompactionPoint.hpp"
 33 #include "gc/g1/g1FullGCMarker.hpp"
 34 #include "gc/g1/g1FullGCOopClosures.inline.hpp"
 35 #include "gc/g1/heapRegion.inline.hpp"
 36 #include "gc/shared/gcTraceTime.inline.hpp"
 37 #include "gc/shared/referenceProcessor.hpp"
 38 #include "gc/shared/weakProcessor.inline.hpp"
 39 #include "logging/log.hpp"
 40 #include "memory/iterator.inline.hpp"
 41 #include "runtime/atomic.hpp"
 42 
 43 class G1AdjustLiveClosure : public StackObj {
 44   G1AdjustClosure* _adjust_closure;
 45 public:
 46   G1AdjustLiveClosure(G1AdjustClosure* cl) :
 47     _adjust_closure(cl) { }
 48 
 49   size_t apply(oop object) {
 50     return object->oop_iterate_size(_adjust_closure);
 51   }
 52 };
 53 
 54 class G1AdjustRegionClosure : public HeapRegionClosure {
 55   G1FullCollector* _collector;
 56   G1CMBitMap* _bitmap;
 57   uint _worker_id;
 58  public:
 59   G1AdjustRegionClosure(G1FullCollector* collector, uint worker_id) :
 60     _collector(collector),
 61     _bitmap(collector->mark_bitmap()),
 62     _worker_id(worker_id) { }
 63 
 64   bool do_heap_region(HeapRegion* r) {
 65     G1AdjustClosure cl(_collector);
 66     if (r->is_humongous()) {
 67       // Special handling for humongous regions to get somewhat better
 68       // work distribution.
 69       oop obj = cast_to_oop(r->humongous_start_region()->bottom());
 70       obj->oop_iterate(&cl, MemRegion(r->bottom(), r->top()));
 71     } else if (!r->is_free()) {
 72       // Free regions do not contain objects to iterate. So skip them.
 73       G1AdjustLiveClosure adjust(&cl);
 74       r->apply_to_marked_objects(_bitmap, &adjust);
 75     }
 76     return false;
 77   }
 78 };
 79 
 80 G1FullGCAdjustTask::G1FullGCAdjustTask(G1FullCollector* collector) :
 81     G1FullGCTask("G1 Adjust", collector),
 82     _root_processor(G1CollectedHeap::heap(), collector->workers()),
 83     _weak_proc_task(collector->workers()),
 84     _hrclaimer(collector->workers()),
 85     _adjust(collector) {
 86   ClassLoaderDataGraph::verify_claimed_marks_cleared(ClassLoaderData::_claim_stw_fullgc_adjust);
 87 }
 88 
 89 void G1FullGCAdjustTask::work(uint worker_id) {
 90   Ticks start = Ticks::now();
 91   ResourceMark rm;
 92 
 93   // Adjust preserved marks first since they are not balanced.
 94   G1FullGCMarker* marker = collector()->marker(worker_id);
 95   marker->preserved_stack()->adjust_during_full_gc();
 96 
 97   {
 98     // Adjust the weak roots.
 99     AlwaysTrueClosure always_alive;
100     _weak_proc_task.work(worker_id, &always_alive, &_adjust);
101   }
102 
103   CLDToOopClosure adjust_cld(&_adjust, ClassLoaderData::_claim_stw_fullgc_adjust);
104   CodeBlobToOopClosure adjust_code(&_adjust, CodeBlobToOopClosure::FixRelocations);
105   _root_processor.process_all_roots(&_adjust, &adjust_cld, &adjust_code);
106 
107   // Now adjust pointers region by region
108   G1AdjustRegionClosure blk(collector(), worker_id);
109   G1CollectedHeap::heap()->heap_region_par_iterate_from_worker_offset(&blk, &_hrclaimer, worker_id);
110   log_task("Adjust task", worker_id, start);
111 }