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src/share/vm/gc_implementation/g1/g1EvacFailure.hpp

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@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2015, 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.

@@ -23,231 +23,26 @@
  */
 
 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1EVACFAILURE_HPP
 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1EVACFAILURE_HPP
 
-#include "gc_implementation/g1/concurrentMark.inline.hpp"
-#include "gc_implementation/g1/dirtyCardQueue.hpp"
-#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
-#include "gc_implementation/g1/g1_globals.hpp"
-#include "gc_implementation/g1/g1OopClosures.inline.hpp"
-#include "gc_implementation/g1/heapRegion.hpp"
-#include "gc_implementation/g1/heapRegionRemSet.hpp"
+#include "gc_implementation/g1/g1OopClosures.hpp"
+#include "gc_implementation/g1/heapRegionManager.hpp"
+#include "utilities/globalDefinitions.hpp"
 #include "utilities/workgroup.hpp"
 
-// Closures and tasks associated with any self-forwarding pointers
-// installed as a result of an evacuation failure.
-
-class UpdateRSetDeferred : public OopsInHeapRegionClosure {
-private:
-  G1CollectedHeap* _g1;
-  DirtyCardQueue *_dcq;
-  G1SATBCardTableModRefBS* _ct_bs;
-
-public:
-  UpdateRSetDeferred(G1CollectedHeap* g1, DirtyCardQueue* dcq) :
-    _g1(g1), _ct_bs(_g1->g1_barrier_set()), _dcq(dcq) {}
-
-  virtual void do_oop(narrowOop* p) { do_oop_work(p); }
-  virtual void do_oop(      oop* p) { do_oop_work(p); }
-  template <class T> void do_oop_work(T* p) {
-    assert(_from->is_in_reserved(p), "paranoia");
-    if (!_from->is_in_reserved(oopDesc::load_decode_heap_oop(p)) &&
-        !_from->is_survivor()) {
-      size_t card_index = _ct_bs->index_for(p);
-      if (_ct_bs->mark_card_deferred(card_index)) {
-        _dcq->enqueue((jbyte*)_ct_bs->byte_for_index(card_index));
-      }
-    }
-  }
-};
-
-class RemoveSelfForwardPtrObjClosure: public ObjectClosure {
-private:
-  G1CollectedHeap* _g1;
-  ConcurrentMark* _cm;
-  HeapRegion* _hr;
-  size_t _marked_bytes;
-  OopsInHeapRegionClosure *_update_rset_cl;
-  bool _during_initial_mark;
-  bool _during_conc_mark;
-  uint _worker_id;
-  HeapWord* _end_of_last_gap;
-  HeapWord* _last_gap_threshold;
-  HeapWord* _last_obj_threshold;
-
-public:
-  RemoveSelfForwardPtrObjClosure(G1CollectedHeap* g1, ConcurrentMark* cm,
-                                 HeapRegion* hr,
-                                 OopsInHeapRegionClosure* update_rset_cl,
-                                 bool during_initial_mark,
-                                 bool during_conc_mark,
-                                 uint worker_id) :
-    _g1(g1), _cm(cm), _hr(hr), _marked_bytes(0),
-    _update_rset_cl(update_rset_cl),
-    _during_initial_mark(during_initial_mark),
-    _during_conc_mark(during_conc_mark),
-    _worker_id(worker_id),
-    _end_of_last_gap(hr->bottom()),
-    _last_gap_threshold(hr->bottom()),
-    _last_obj_threshold(hr->bottom()) { }
-
-  size_t marked_bytes() { return _marked_bytes; }
-
-  // <original comment>
-  // The original idea here was to coalesce evacuated and dead objects.
-  // However that caused complications with the block offset table (BOT).
-  // In particular if there were two TLABs, one of them partially refined.
-  // |----- TLAB_1--------|----TLAB_2-~~~(partially refined part)~~~|
-  // The BOT entries of the unrefined part of TLAB_2 point to the start
-  // of TLAB_2. If the last object of the TLAB_1 and the first object
-  // of TLAB_2 are coalesced, then the cards of the unrefined part
-  // would point into middle of the filler object.
-  // The current approach is to not coalesce and leave the BOT contents intact.
-  // </original comment>
-  //
-  // We now reset the BOT when we start the object iteration over the
-  // region and refine its entries for every object we come across. So
-  // the above comment is not really relevant and we should be able
-  // to coalesce dead objects if we want to.
-  void do_object(oop obj) {
-    HeapWord* obj_addr = (HeapWord*) obj;
-    assert(_hr->is_in(obj_addr), "sanity");
-    size_t obj_size = obj->size();
-    HeapWord* obj_end = obj_addr + obj_size;
-
-    if (_end_of_last_gap != obj_addr) {
-      // there was a gap before obj_addr
-      _last_gap_threshold = _hr->cross_threshold(_end_of_last_gap, obj_addr);
-    }
-
-    if (obj->is_forwarded() && obj->forwardee() == obj) {
-      // The object failed to move.
-
-      // We consider all objects that we find self-forwarded to be
-      // live. What we'll do is that we'll update the prev marking
-      // info so that they are all under PTAMS and explicitly marked.
-      if (!_cm->isPrevMarked(obj)) {
-        _cm->markPrev(obj);
-      }
-      if (_during_initial_mark) {
-        // For the next marking info we'll only mark the
-        // self-forwarded objects explicitly if we are during
-        // initial-mark (since, normally, we only mark objects pointed
-        // to by roots if we succeed in copying them). By marking all
-        // self-forwarded objects we ensure that we mark any that are
-        // still pointed to be roots. During concurrent marking, and
-        // after initial-mark, we don't need to mark any objects
-        // explicitly and all objects in the CSet are considered
-        // (implicitly) live. So, we won't mark them explicitly and
-        // we'll leave them over NTAMS.
-        _cm->grayRoot(obj, obj_size, _worker_id, _hr);
-      }
-      _marked_bytes += (obj_size * HeapWordSize);
-      obj->set_mark(markOopDesc::prototype());
-
-      // While we were processing RSet buffers during the collection,
-      // we actually didn't scan any cards on the collection set,
-      // since we didn't want to update remembered sets with entries
-      // that point into the collection set, given that live objects
-      // from the collection set are about to move and such entries
-      // will be stale very soon.
-      // This change also dealt with a reliability issue which
-      // involved scanning a card in the collection set and coming
-      // across an array that was being chunked and looking malformed.
-      // The problem is that, if evacuation fails, we might have
-      // remembered set entries missing given that we skipped cards on
-      // the collection set. So, we'll recreate such entries now.
-      obj->oop_iterate(_update_rset_cl);
-    } else {
-
-      // The object has been either evacuated or is dead. Fill it with a
-      // dummy object.
-      MemRegion mr(obj_addr, obj_size);
-      CollectedHeap::fill_with_object(mr);
-
-      // must nuke all dead objects which we skipped when iterating over the region
-      _cm->clearRangePrevBitmap(MemRegion(_end_of_last_gap, obj_end));
-    }
-    _end_of_last_gap = obj_end;
-    _last_obj_threshold = _hr->cross_threshold(obj_addr, obj_end);
-  }
-};
-
-class RemoveSelfForwardPtrHRClosure: public HeapRegionClosure {
-  G1CollectedHeap* _g1h;
-  ConcurrentMark* _cm;
-  uint _worker_id;
-  HeapRegionClaimer* _hrclaimer;
-
-  DirtyCardQueue _dcq;
-  UpdateRSetDeferred _update_rset_cl;
-
-public:
-  RemoveSelfForwardPtrHRClosure(G1CollectedHeap* g1h,
-                                uint worker_id,
-                                HeapRegionClaimer* hrclaimer) :
-      _g1h(g1h), _dcq(&g1h->dirty_card_queue_set()), _update_rset_cl(g1h, &_dcq),
-      _worker_id(worker_id), _cm(_g1h->concurrent_mark()), _hrclaimer(hrclaimer) {
-  }
-
-  bool doHeapRegion(HeapRegion *hr) {
-    bool during_initial_mark = _g1h->g1_policy()->during_initial_mark_pause();
-    bool during_conc_mark = _g1h->mark_in_progress();
-
-    assert(!hr->is_humongous(), "sanity");
-    assert(hr->in_collection_set(), "bad CS");
-
-    if (_hrclaimer->claim_region(hr->hrm_index())) {
-      if (hr->evacuation_failed()) {
-        RemoveSelfForwardPtrObjClosure rspc(_g1h, _cm, hr, &_update_rset_cl,
-                                            during_initial_mark,
-                                            during_conc_mark,
-                                            _worker_id);
-
-        hr->note_self_forwarding_removal_start(during_initial_mark,
-                                               during_conc_mark);
-        _g1h->check_bitmaps("Self-Forwarding Ptr Removal", hr);
-
-        // In the common case (i.e. when there is no evacuation
-        // failure) we make sure that the following is done when
-        // the region is freed so that it is "ready-to-go" when it's
-        // re-allocated. However, when evacuation failure happens, a
-        // region will remain in the heap and might ultimately be added
-        // to a CSet in the future. So we have to be careful here and
-        // make sure the region's RSet is ready for parallel iteration
-        // whenever this might be required in the future.
-        hr->rem_set()->reset_for_par_iteration();
-        hr->reset_bot();
-        _update_rset_cl.set_region(hr);
-        hr->object_iterate(&rspc);
-
-        hr->rem_set()->clean_strong_code_roots(hr);
-
-        hr->note_self_forwarding_removal_end(during_initial_mark,
-                                             during_conc_mark,
-                                             rspc.marked_bytes());
-      }
-    }
-    return false;
-  }
-};
+class G1CollectedHeap;
 
+// Task to fixup self-forwarding pointers
+// installed as a result of an evacuation failure.
 class G1ParRemoveSelfForwardPtrsTask: public AbstractGangTask {
 protected:
   G1CollectedHeap* _g1h;
   HeapRegionClaimer _hrclaimer;
 
 public:
-  G1ParRemoveSelfForwardPtrsTask(G1CollectedHeap* g1h) :
-      AbstractGangTask("G1 Remove Self-forwarding Pointers"), _g1h(g1h),
-      _hrclaimer(g1h->workers()->active_workers()) {}
-
-  void work(uint worker_id) {
-    RemoveSelfForwardPtrHRClosure rsfp_cl(_g1h, worker_id, &_hrclaimer);
-
-    HeapRegion* hr = _g1h->start_cset_region_for_worker(worker_id);
-    _g1h->collection_set_iterate_from(hr, &rsfp_cl);
-  }
+  G1ParRemoveSelfForwardPtrsTask(G1CollectedHeap* g1h);
+
+  void work(uint worker_id);
 };
 
 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1EVACFAILURE_HPP
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