jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/g1/concurrentMarkThread.hpp@4dfb2df418f2

6484982: G1: process references during evacuation pauses
Summary: G1 now uses two reference processors - one is used by concurrent marking and the other is used by STW GCs (both full and incremental evacuation pauses). In an evacuation pause, the reference processor is embedded into the closures used to scan objects. Doing so causes causes reference objects to be 'discovered' by the reference processor. At the end of the evacuation pause, these discovered reference objects are processed - preserving (and copying) referent objects (and their reachable graphs) as appropriate.
Reviewed-by: ysr, jwilhelm, brutisso, stefank, tonyp

     1 /*

     2  * Copyright (c) 2001, 2010, 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

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    23  */

    25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARKTHREAD_HPP

    26 #define SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARKTHREAD_HPP

    28 #include "gc_implementation/shared/concurrentGCThread.hpp"

    30 // The Concurrent Mark GC Thread (could be several in the future).

    31 // This is copied from the Concurrent Mark Sweep GC Thread

    32 // Still under construction.

    34 class ConcurrentMark;

    36 class ConcurrentMarkThread: public ConcurrentGCThread {

    37   friend class VMStructs;

    39   double _vtime_start;  // Initial virtual time.

    40   double _vtime_accum;  // Accumulated virtual time.

    42   double _vtime_mark_accum;

    43   double _vtime_count_accum;

    45  public:

    46   virtual void run();

    48  private:

    49   ConcurrentMark*                  _cm;

    50   volatile bool                    _started;

    51   volatile bool                    _in_progress;

    53   void sleepBeforeNextCycle();

    55   static SurrogateLockerThread*         _slt;

    57  public:

    58   // Constructor

    59   ConcurrentMarkThread(ConcurrentMark* cm);

    61   static void makeSurrogateLockerThread(TRAPS);

    62   static SurrogateLockerThread* slt() { return _slt; }

    64   // Printing

    65   void print_on(outputStream* st) const;

    66   void print() const;

    68   // Total virtual time so far.

    69   double vtime_accum();

    70   // Marking virtual time so far

    71   double vtime_mark_accum();

    72   // Counting virtual time so far.

    73   double vtime_count_accum() { return _vtime_count_accum; }

    75   ConcurrentMark* cm()     { return _cm; }

    77   void set_started()       { assert(!_in_progress, "cycle in progress"); _started = true;  }

    78   void clear_started()     { assert(_in_progress, "must be starting a cycle"); _started = false; }

    79   bool started()           { return _started;  }

    81   void set_in_progress()   { assert(_started, "must be starting a cycle"); _in_progress = true;  }

    82   void clear_in_progress() { assert(!_started, "must not be starting a new cycle"); _in_progress = false; }

    83   bool in_progress()       { return _in_progress;  }

    85   // This flag returns true from the moment a marking cycle is

    86   // initiated (during the initial-mark pause when started() is set)

    87   // to the moment when the cycle completes (just after the next

    88   // marking bitmap has been cleared and in_progress() is

    89   // cleared). While this flag is true we will not start another cycle

    90   // so that cycles do not overlap. We cannot use just in_progress()

    91   // as the CM thread might take some time to wake up before noticing

    92   // that started() is set and set in_progress().

    93   bool during_cycle()      { return started() || in_progress(); }

    95   // Yield for GC

    96   void            yield();

    98   // shutdown

    99   void stop();

   100 };

   102 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARKTHREAD_HPP

Mercurial > jdk8-mips64-public > hotspot / file revision

src/share/vm/gc_implementation/g1/concurrentMarkThread.hpp@4dfb2df418f2

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