jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/shared/markSweep.cpp@0bfd3fb24150 (annotated)

src/share/vm/gc_implementation/shared/markSweep.cpp@0bfd3fb24150 (annotated)

src/share/vm/gc_implementation/shared/markSweep.cpp

Tue, 13 Apr 2010 13:52:10 -0700

author: jmasa
date: Tue, 13 Apr 2010 13:52:10 -0700
changeset 1822: 0bfd3fb24150
parent 1750: c385bf94cfb8
child 1907: c18cbe5936b8
permissions: -rw-r--r--

6858496: Clear all SoftReferences before an out-of-memory due to GC overhead limit.
Summary: Ensure a full GC that clears SoftReferences before throwing an out-of-memory
Reviewed-by: ysr, jcoomes

 /*
  * Copyright 1997-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  * CA 95054 USA or visit www.sun.com if you need additional information or
  * have any questions.
  *
  */
 #include "incls/_precompiled.incl"
 #include "incls/_markSweep.cpp.incl"
 GrowableArray<oop>*          MarkSweep::_marking_stack = NULL;
 GrowableArray<ObjArrayTask>* MarkSweep::_objarray_stack = NULL;
 GrowableArray<Klass*>*       MarkSweep::_revisit_klass_stack = NULL;
 GrowableArray<DataLayout*>*  MarkSweep::_revisit_mdo_stack = NULL;
 GrowableArray<oop>*     MarkSweep::_preserved_oop_stack = NULL;
 GrowableArray<markOop>* MarkSweep::_preserved_mark_stack= NULL;
 size_t                  MarkSweep::_preserved_count = 0;
 size_t                  MarkSweep::_preserved_count_max = 0;
 PreservedMark*          MarkSweep::_preserved_marks = NULL;
 ReferenceProcessor*     MarkSweep::_ref_processor   = NULL;
 #ifdef VALIDATE_MARK_SWEEP
 GrowableArray<void*>*   MarkSweep::_root_refs_stack = NULL;
 GrowableArray<oop> *    MarkSweep::_live_oops = NULL;
 GrowableArray<oop> *    MarkSweep::_live_oops_moved_to = NULL;
 GrowableArray<size_t>*  MarkSweep::_live_oops_size = NULL;
 size_t                  MarkSweep::_live_oops_index = 0;
 size_t                  MarkSweep::_live_oops_index_at_perm = 0;
 GrowableArray<void*>*   MarkSweep::_other_refs_stack = NULL;
 GrowableArray<void*>*   MarkSweep::_adjusted_pointers = NULL;
 bool                         MarkSweep::_pointer_tracking = false;
 bool                         MarkSweep::_root_tracking = true;
 GrowableArray<HeapWord*>* MarkSweep::_cur_gc_live_oops = NULL;
 GrowableArray<HeapWord*>* MarkSweep::_cur_gc_live_oops_moved_to = NULL;
 GrowableArray<size_t>   * MarkSweep::_cur_gc_live_oops_size = NULL;
 GrowableArray<HeapWord*>* MarkSweep::_last_gc_live_oops = NULL;
 GrowableArray<HeapWord*>* MarkSweep::_last_gc_live_oops_moved_to = NULL;
 GrowableArray<size_t>   * MarkSweep::_last_gc_live_oops_size = NULL;
 #endif
 void MarkSweep::revisit_weak_klass_link(Klass* k) {
   _revisit_klass_stack->push(k);
 }
 void MarkSweep::follow_weak_klass_links() {
   // All klasses on the revisit stack are marked at this point.
   // Update and follow all subklass, sibling and implementor links.
   if (PrintRevisitStats) {
     gclog_or_tty->print_cr("#classes in system dictionary = %d", SystemDictionary::number_of_classes());
     gclog_or_tty->print_cr("Revisit klass stack length = %d", _revisit_klass_stack->length());
   }
   for (int i = 0; i < _revisit_klass_stack->length(); i++) {
     _revisit_klass_stack->at(i)->follow_weak_klass_links(&is_alive,&keep_alive);
   }
   follow_stack();
 }
 void MarkSweep::revisit_mdo(DataLayout* p) {
   _revisit_mdo_stack->push(p);
 }
 void MarkSweep::follow_mdo_weak_refs() {
   // All strongly reachable oops have been marked at this point;
   // we can visit and clear any weak references from MDO's which
   // we memoized during the strong marking phase.
   assert(_marking_stack->is_empty(), "Marking stack should be empty");
   if (PrintRevisitStats) {
     gclog_or_tty->print_cr("#classes in system dictionary = %d", SystemDictionary::number_of_classes());
     gclog_or_tty->print_cr("Revisit MDO stack length = %d", _revisit_mdo_stack->length());
   }
   for (int i = 0; i < _revisit_mdo_stack->length(); i++) {
     _revisit_mdo_stack->at(i)->follow_weak_refs(&is_alive);
   }
   follow_stack();
 }
 MarkSweep::FollowRootClosure  MarkSweep::follow_root_closure;
 CodeBlobToOopClosure MarkSweep::follow_code_root_closure(&MarkSweep::follow_root_closure, /*do_marking=*/ true);
 void MarkSweep::FollowRootClosure::do_oop(oop* p)       { follow_root(p); }
 void MarkSweep::FollowRootClosure::do_oop(narrowOop* p) { follow_root(p); }
 MarkSweep::MarkAndPushClosure MarkSweep::mark_and_push_closure;
 void MarkSweep::MarkAndPushClosure::do_oop(oop* p)       { mark_and_push(p); }
 void MarkSweep::MarkAndPushClosure::do_oop(narrowOop* p) { mark_and_push(p); }
 void MarkSweep::follow_stack() {
   do {
     while (!_marking_stack->is_empty()) {
       oop obj = _marking_stack->pop();
       assert (obj->is_gc_marked(), "p must be marked");
       obj->follow_contents();
     }
     // Process ObjArrays one at a time to avoid marking stack bloat.
     if (!_objarray_stack->is_empty()) {
       ObjArrayTask task = _objarray_stack->pop();
       objArrayKlass* const k = (objArrayKlass*)task.obj()->blueprint();
       k->oop_follow_contents(task.obj(), task.index());
     }
   } while (!_marking_stack->is_empty() || !_objarray_stack->is_empty());
 }
 MarkSweep::FollowStackClosure MarkSweep::follow_stack_closure;
 void MarkSweep::FollowStackClosure::do_void() { follow_stack(); }
 // We preserve the mark which should be replaced at the end and the location that it
 // will go.  Note that the object that this markOop belongs to isn't currently at that
 // address but it will be after phase4
 void MarkSweep::preserve_mark(oop obj, markOop mark) {
   // we try to store preserved marks in the to space of the new generation since this
   // is storage which should be available.  Most of the time this should be sufficient
   // space for the marks we need to preserve but if it isn't we fall back in using
   // GrowableArrays to keep track of the overflow.
   if (_preserved_count < _preserved_count_max) {
     _preserved_marks[_preserved_count++].init(obj, mark);
   } else {
     if (_preserved_mark_stack == NULL) {
       _preserved_mark_stack = new (ResourceObj::C_HEAP) GrowableArray<markOop>(40, true);
       _preserved_oop_stack = new (ResourceObj::C_HEAP) GrowableArray<oop>(40, true);
     }
     _preserved_mark_stack->push(mark);
     _preserved_oop_stack->push(obj);
   }
 }
 MarkSweep::AdjustPointerClosure MarkSweep::adjust_root_pointer_closure(true);
 MarkSweep::AdjustPointerClosure MarkSweep::adjust_pointer_closure(false);
 void MarkSweep::AdjustPointerClosure::do_oop(oop* p)       { adjust_pointer(p, _is_root); }
 void MarkSweep::AdjustPointerClosure::do_oop(narrowOop* p) { adjust_pointer(p, _is_root); }
 void MarkSweep::adjust_marks() {
   assert(_preserved_oop_stack == NULL ||
          _preserved_oop_stack->length() == _preserved_mark_stack->length(),
          "inconsistent preserved oop stacks");
   // adjust the oops we saved earlier
   for (size_t i = 0; i < _preserved_count; i++) {
     _preserved_marks[i].adjust_pointer();
   }
   // deal with the overflow stack
   if (_preserved_oop_stack) {
     for (int i = 0; i < _preserved_oop_stack->length(); i++) {
       oop* p = _preserved_oop_stack->adr_at(i);
       adjust_pointer(p);
     }
   }
 }
 void MarkSweep::restore_marks() {
   assert(_preserved_oop_stack == NULL ||
          _preserved_oop_stack->length() == _preserved_mark_stack->length(),
          "inconsistent preserved oop stacks");
   if (PrintGC && Verbose) {
     gclog_or_tty->print_cr("Restoring %d marks", _preserved_count +
                   (_preserved_oop_stack ? _preserved_oop_stack->length() : 0));
   }
   // restore the marks we saved earlier
   for (size_t i = 0; i < _preserved_count; i++) {
     _preserved_marks[i].restore();
   }
   // deal with the overflow
   if (_preserved_oop_stack) {
     for (int i = 0; i < _preserved_oop_stack->length(); i++) {
       oop obj       = _preserved_oop_stack->at(i);
       markOop mark  = _preserved_mark_stack->at(i);
       obj->set_mark(mark);
     }
   }
 }
 #ifdef VALIDATE_MARK_SWEEP
 void MarkSweep::track_adjusted_pointer(void* p, bool isroot) {
   if (!ValidateMarkSweep)
     return;
   if (!isroot) {
     if (_pointer_tracking) {
       guarantee(_adjusted_pointers->contains(p), "should have seen this pointer");
       _adjusted_pointers->remove(p);
     }
   } else {
     ptrdiff_t index = _root_refs_stack->find(p);
     if (index != -1) {
       int l = _root_refs_stack->length();
       if (l > 0 && l - 1 != index) {
         void* last = _root_refs_stack->pop();
         assert(last != p, "should be different");
         _root_refs_stack->at_put(index, last);
       } else {
         _root_refs_stack->remove(p);
       }
     }
   }
 }
 void MarkSweep::check_adjust_pointer(void* p) {
   _adjusted_pointers->push(p);
 }
 class AdjusterTracker: public OopClosure {
  public:
   AdjusterTracker() {}
   void do_oop(oop* o)       { MarkSweep::check_adjust_pointer(o); }
   void do_oop(narrowOop* o) { MarkSweep::check_adjust_pointer(o); }
 };
 void MarkSweep::track_interior_pointers(oop obj) {
   if (ValidateMarkSweep) {
     _adjusted_pointers->clear();
     _pointer_tracking = true;
     AdjusterTracker checker;
     obj->oop_iterate(&checker);
   }
 }
 void MarkSweep::check_interior_pointers() {
   if (ValidateMarkSweep) {
     _pointer_tracking = false;
     guarantee(_adjusted_pointers->length() == 0, "should have processed the same pointers");
   }
 }
 void MarkSweep::reset_live_oop_tracking(bool at_perm) {
   if (ValidateMarkSweep) {
     guarantee((size_t)_live_oops->length() == _live_oops_index, "should be at end of live oops");
     _live_oops_index = at_perm ? _live_oops_index_at_perm : 0;
   }
 }
 void MarkSweep::register_live_oop(oop p, size_t size) {
   if (ValidateMarkSweep) {
     _live_oops->push(p);
     _live_oops_size->push(size);
     _live_oops_index++;
   }
 }
 void MarkSweep::validate_live_oop(oop p, size_t size) {
   if (ValidateMarkSweep) {
     oop obj = _live_oops->at((int)_live_oops_index);
     guarantee(obj == p, "should be the same object");
     guarantee(_live_oops_size->at((int)_live_oops_index) == size, "should be the same size");
     _live_oops_index++;
   }
 }
 void MarkSweep::live_oop_moved_to(HeapWord* q, size_t size,
                                   HeapWord* compaction_top) {
   assert(oop(q)->forwardee() == NULL || oop(q)->forwardee() == oop(compaction_top),
          "should be moved to forwarded location");
   if (ValidateMarkSweep) {
     MarkSweep::validate_live_oop(oop(q), size);
     _live_oops_moved_to->push(oop(compaction_top));
   }
   if (RecordMarkSweepCompaction) {
     _cur_gc_live_oops->push(q);
     _cur_gc_live_oops_moved_to->push(compaction_top);
     _cur_gc_live_oops_size->push(size);
   }
 }
 void MarkSweep::compaction_complete() {
   if (RecordMarkSweepCompaction) {
     GrowableArray<HeapWord*>* _tmp_live_oops          = _cur_gc_live_oops;
     GrowableArray<HeapWord*>* _tmp_live_oops_moved_to = _cur_gc_live_oops_moved_to;
     GrowableArray<size_t>   * _tmp_live_oops_size     = _cur_gc_live_oops_size;
     _cur_gc_live_oops           = _last_gc_live_oops;
     _cur_gc_live_oops_moved_to  = _last_gc_live_oops_moved_to;
     _cur_gc_live_oops_size      = _last_gc_live_oops_size;
     _last_gc_live_oops          = _tmp_live_oops;
     _last_gc_live_oops_moved_to = _tmp_live_oops_moved_to;
     _last_gc_live_oops_size     = _tmp_live_oops_size;
   }
 }
 void MarkSweep::print_new_location_of_heap_address(HeapWord* q) {
   if (!RecordMarkSweepCompaction) {
     tty->print_cr("Requires RecordMarkSweepCompaction to be enabled");
     return;
   }
   if (_last_gc_live_oops == NULL) {
     tty->print_cr("No compaction information gathered yet");
     return;
   }
   for (int i = 0; i < _last_gc_live_oops->length(); i++) {
     HeapWord* old_oop = _last_gc_live_oops->at(i);
     size_t    sz      = _last_gc_live_oops_size->at(i);
     if (old_oop <= q && q < (old_oop + sz)) {
       HeapWord* new_oop = _last_gc_live_oops_moved_to->at(i);
       size_t offset = (q - old_oop);
       tty->print_cr("Address " PTR_FORMAT, q);
       tty->print_cr(" Was in oop " PTR_FORMAT ", size " SIZE_FORMAT ", at offset " SIZE_FORMAT, old_oop, sz, offset);
       tty->print_cr(" Now in oop " PTR_FORMAT ", actual address " PTR_FORMAT, new_oop, new_oop + offset);
       return;
     }
   }
   tty->print_cr("Address " PTR_FORMAT " not found in live oop information from last GC", q);
 }
 #endif //VALIDATE_MARK_SWEEP
 MarkSweep::IsAliveClosure   MarkSweep::is_alive;
 void MarkSweep::IsAliveClosure::do_object(oop p)   { ShouldNotReachHere(); }
 bool MarkSweep::IsAliveClosure::do_object_b(oop p) { return p->is_gc_marked(); }
 MarkSweep::KeepAliveClosure MarkSweep::keep_alive;
 void MarkSweep::KeepAliveClosure::do_oop(oop* p)       { MarkSweep::KeepAliveClosure::do_oop_work(p); }
 void MarkSweep::KeepAliveClosure::do_oop(narrowOop* p) { MarkSweep::KeepAliveClosure::do_oop_work(p); }
 void marksweep_init() { /* empty */ }
 #ifndef PRODUCT
 void MarkSweep::trace(const char* msg) {
   if (TraceMarkSweep)
     gclog_or_tty->print("%s", msg);
 }
 #endif

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/shared/markSweep.cpp@0bfd3fb24150 (annotated)

src/share/vm/gc_implementation/shared/markSweep.cpp