jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/bufferingOopClosure.hpp@0bfd3fb24150 (annotated)

src/share/vm/gc_implementation/g1/bufferingOopClosure.hpp@0bfd3fb24150 (annotated)

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

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

author: jmasa
date: Tue, 13 Apr 2010 13:52:10 -0700
changeset 1822: 0bfd3fb24150
parent 1280: df6caf649ff7
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 2001-2007 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.
  *
  */
 // A BufferingOops closure tries to separate out the cost of finding roots
 // from the cost of applying closures to them.  It maintains an array of
 // ref-containing locations.  Until the array is full, applying the closure
 // to an oop* merely records that location in the array.  Since this
 // closure app cost is small, an elapsed timer can approximately attribute
 // all of this cost to the cost of finding the roots.  When the array fills
 // up, the wrapped closure is applied to all elements, keeping track of
 // this elapsed time of this process, and leaving the array empty.
 // The caller must be sure to call "done" to process any unprocessed
 // buffered entriess.
 class Generation;
 class HeapRegion;
 class BufferingOopClosure: public OopClosure {
 protected:
   enum PrivateConstants {
     BufferLength = 1024
   };
   StarTask  _buffer[BufferLength];
   StarTask* _buffer_top;
   StarTask* _buffer_curr;
   OopClosure* _oc;
   double      _closure_app_seconds;
   void process_buffer () {
     double start = os::elapsedTime();
     for (StarTask* curr = _buffer; curr < _buffer_curr; ++curr) {
       if (curr->is_narrow()) {
         assert(UseCompressedOops, "Error");
         _oc->do_oop((narrowOop*)(*curr));
       } else {
         _oc->do_oop((oop*)(*curr));
       }
     }
     _buffer_curr = _buffer;
     _closure_app_seconds += (os::elapsedTime() - start);
   }
   template <class T> inline void do_oop_work(T* p) {
     if (_buffer_curr == _buffer_top) {
       process_buffer();
     }
     StarTask new_ref(p);
     *_buffer_curr = new_ref;
     ++_buffer_curr;
   }
 public:
   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
   virtual void do_oop(oop* p)       { do_oop_work(p); }
   void done () {
     if (_buffer_curr > _buffer) {
       process_buffer();
     }
   }
   double closure_app_seconds () {
     return _closure_app_seconds;
   }
   BufferingOopClosure (OopClosure *oc) :
     _oc(oc),
     _buffer_curr(_buffer), _buffer_top(_buffer + BufferLength),
     _closure_app_seconds(0.0) { }
 };
 class BufferingOopsInGenClosure: public OopsInGenClosure {
   BufferingOopClosure _boc;
   OopsInGenClosure* _oc;
  protected:
   template <class T> inline void do_oop_work(T* p) {
     assert(generation()->is_in_reserved((void*)p), "Must be in!");
     _boc.do_oop(p);
   }
  public:
   BufferingOopsInGenClosure(OopsInGenClosure *oc) :
     _boc(oc), _oc(oc) {}
   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
   virtual void do_oop(oop* p)       { do_oop_work(p); }
   void done() {
     _boc.done();
   }
   double closure_app_seconds () {
     return _boc.closure_app_seconds();
   }
   void set_generation(Generation* gen) {
     OopsInGenClosure::set_generation(gen);
     _oc->set_generation(gen);
   }
   void reset_generation() {
     // Make sure we finish the current work with the current generation.
     _boc.done();
     OopsInGenClosure::reset_generation();
     _oc->reset_generation();
   }
 };
 class BufferingOopsInHeapRegionClosure: public OopsInHeapRegionClosure {
 private:
   enum PrivateConstants {
     BufferLength = 1024
   };
   StarTask     _buffer[BufferLength];
   StarTask*    _buffer_top;
   StarTask*    _buffer_curr;
   HeapRegion*  _hr_buffer[BufferLength];
   HeapRegion** _hr_curr;
   OopsInHeapRegionClosure*  _oc;
   double                    _closure_app_seconds;
   void process_buffer () {
     assert((_hr_curr - _hr_buffer) == (_buffer_curr - _buffer),
            "the two lengths should be the same");
     double start = os::elapsedTime();
     HeapRegion** hr_curr = _hr_buffer;
     HeapRegion*  hr_prev = NULL;
     for (StarTask* curr = _buffer; curr < _buffer_curr; ++curr) {
       HeapRegion* region = *hr_curr;
       if (region != hr_prev) {
         _oc->set_region(region);
         hr_prev = region;
       }
       if (curr->is_narrow()) {
         assert(UseCompressedOops, "Error");
         _oc->do_oop((narrowOop*)(*curr));
       } else {
         _oc->do_oop((oop*)(*curr));
       }
       ++hr_curr;
     }
     _buffer_curr = _buffer;
     _hr_curr = _hr_buffer;
     _closure_app_seconds += (os::elapsedTime() - start);
   }
 public:
   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) {
     if (_buffer_curr == _buffer_top) {
       assert(_hr_curr > _hr_buffer, "_hr_curr should be consistent with _buffer_curr");
       process_buffer();
     }
     StarTask new_ref(p);
     *_buffer_curr = new_ref;
     ++_buffer_curr;
     *_hr_curr = _from;
     ++_hr_curr;
   }
   void done () {
     if (_buffer_curr > _buffer) {
       assert(_hr_curr > _hr_buffer, "_hr_curr should be consistent with _buffer_curr");
       process_buffer();
     }
   }
   double closure_app_seconds () {
     return _closure_app_seconds;
   }
   BufferingOopsInHeapRegionClosure (OopsInHeapRegionClosure *oc) :
     _oc(oc),
     _buffer_curr(_buffer), _buffer_top(_buffer + BufferLength),
     _hr_curr(_hr_buffer),
     _closure_app_seconds(0.0) { }
 };

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/gc_implementation/g1/bufferingOopClosure.hpp@0bfd3fb24150 (annotated)

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