Tue, 26 Jan 2010 16:52:29 -0800
6920090: G1: Disable ReduceInitialCardMarks at least until 6920109 is fixed
Summary: G1 now answers "no" to the query can_elide_initializing_store_barrier() in the product build. A debug flag allows alternate behaviour in debug builds.
Reviewed-by: iveresov, tonyp
1 /*
2 * Copyright 2001-2009 Sun Microsystems, Inc. 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).
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15 * You should have received a copy of the GNU General Public License version
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17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
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23 */
25 // Forward Decl.
26 class ConcurrentG1Refine;
28 // The G1 Concurrent Refinement Thread (could be several in the future).
30 class ConcurrentG1RefineThread: public ConcurrentGCThread {
31 friend class VMStructs;
32 friend class G1CollectedHeap;
34 double _vtime_start; // Initial virtual time.
35 double _vtime_accum; // Initial virtual time.
36 int _worker_id;
37 int _worker_id_offset;
39 // The refinement threads collection is linked list. A predecessor can activate a successor
40 // when the number of the rset update buffer crosses a certain threshold. A successor
41 // would self-deactivate when the number of the buffers falls below the threshold.
42 bool _active;
43 ConcurrentG1RefineThread* _next;
44 Monitor* _monitor;
45 ConcurrentG1Refine* _cg1r;
47 int _thread_threshold_step;
48 // This thread activation threshold
49 int _threshold;
50 // This thread deactivation threshold
51 int _deactivation_threshold;
53 void sample_young_list_rs_lengths();
54 void run_young_rs_sampling();
55 void wait_for_completed_buffers();
57 void set_active(bool x) { _active = x; }
58 bool is_active();
59 void activate();
60 void deactivate();
62 // For use by G1CollectedHeap, which is a friend.
63 static SuspendibleThreadSet* sts() { return &_sts; }
65 public:
66 virtual void run();
67 // Constructor
68 ConcurrentG1RefineThread(ConcurrentG1Refine* cg1r, ConcurrentG1RefineThread* next,
69 int worker_id_offset, int worker_id);
71 void initialize();
73 // Printing
74 void print() const;
75 void print_on(outputStream* st) const;
77 // Total virtual time so far.
78 double vtime_accum() { return _vtime_accum; }
80 ConcurrentG1Refine* cg1r() { return _cg1r; }
82 // Yield for GC
83 void yield();
84 // shutdown
85 void stop();
86 };