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 2001-2007 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).
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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 #ifndef SERIALGC
27 class DirtyCardQueueSet;
29 // This barrier is specialized to use a logging barrier to support
30 // snapshot-at-the-beginning marking.
32 class G1SATBCardTableModRefBS: public CardTableModRefBSForCTRS {
33 private:
34 // Add "pre_val" to a set of objects that may have been disconnected from the
35 // pre-marking object graph.
36 static void enqueue(oop pre_val);
38 public:
39 G1SATBCardTableModRefBS(MemRegion whole_heap,
40 int max_covered_regions);
42 bool is_a(BarrierSet::Name bsn) {
43 return bsn == BarrierSet::G1SATBCT || CardTableModRefBS::is_a(bsn);
44 }
46 virtual bool has_write_ref_pre_barrier() { return true; }
48 // This notes that we don't need to access any BarrierSet data
49 // structures, so this can be called from a static context.
50 template <class T> static void write_ref_field_pre_static(T* field, oop newVal) {
51 T heap_oop = oopDesc::load_heap_oop(field);
52 if (!oopDesc::is_null(heap_oop)) {
53 enqueue(oopDesc::decode_heap_oop(heap_oop));
54 }
55 }
57 // When we know the current java thread:
58 template <class T> static void write_ref_field_pre_static(T* field, oop newVal,
59 JavaThread* jt);
61 // We export this to make it available in cases where the static
62 // type of the barrier set is known. Note that it is non-virtual.
63 template <class T> inline void inline_write_ref_field_pre(T* field, oop newVal) {
64 write_ref_field_pre_static(field, newVal);
65 }
67 // These are the more general virtual versions.
68 virtual void write_ref_field_pre_work(oop* field, oop new_val) {
69 inline_write_ref_field_pre(field, new_val);
70 }
71 virtual void write_ref_field_pre_work(narrowOop* field, oop new_val) {
72 inline_write_ref_field_pre(field, new_val);
73 }
74 virtual void write_ref_field_pre_work(void* field, oop new_val) {
75 guarantee(false, "Not needed");
76 }
78 template <class T> void write_ref_array_pre_work(T* dst, int count);
79 virtual void write_ref_array_pre(oop* dst, int count) {
80 write_ref_array_pre_work(dst, count);
81 }
82 virtual void write_ref_array_pre(narrowOop* dst, int count) {
83 write_ref_array_pre_work(dst, count);
84 }
85 };
87 // Adds card-table logging to the post-barrier.
88 // Usual invariant: all dirty cards are logged in the DirtyCardQueueSet.
89 class G1SATBCardTableLoggingModRefBS: public G1SATBCardTableModRefBS {
90 private:
91 DirtyCardQueueSet& _dcqs;
92 public:
93 G1SATBCardTableLoggingModRefBS(MemRegion whole_heap,
94 int max_covered_regions);
96 bool is_a(BarrierSet::Name bsn) {
97 return bsn == BarrierSet::G1SATBCTLogging ||
98 G1SATBCardTableModRefBS::is_a(bsn);
99 }
101 void write_ref_field_work(void* field, oop new_val);
103 // Can be called from static contexts.
104 static void write_ref_field_static(void* field, oop new_val);
106 // NB: if you do a whole-heap invalidation, the "usual invariant" defined
107 // above no longer applies.
108 void invalidate(MemRegion mr, bool whole_heap = false);
110 void write_region_work(MemRegion mr) { invalidate(mr); }
111 void write_ref_array_work(MemRegion mr) { invalidate(mr); }
114 };
117 #endif // SERIALGC