Mon, 03 Aug 2009 12:59:30 -0700
6865703: G1: Parallelize hot card cache cleanup
Summary: Have the GC worker threads clear the hot card cache in parallel by having each worker thread claim a chunk of the card cache and process the cards in that chunk. The size of the chunks that each thread will claim is determined at VM initialization from the size of the card cache and the number of worker threads.
Reviewed-by: jmasa, 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 #include "incls/_precompiled.incl"
26 #include "incls/_g1SATBCardTableModRefBS.cpp.incl"
28 G1SATBCardTableModRefBS::G1SATBCardTableModRefBS(MemRegion whole_heap,
29 int max_covered_regions) :
30 CardTableModRefBSForCTRS(whole_heap, max_covered_regions)
31 {
32 _kind = G1SATBCT;
33 }
36 void G1SATBCardTableModRefBS::enqueue(oop pre_val) {
37 assert(pre_val->is_oop_or_null(true), "Error");
38 if (!JavaThread::satb_mark_queue_set().active()) return;
39 Thread* thr = Thread::current();
40 if (thr->is_Java_thread()) {
41 JavaThread* jt = (JavaThread*)thr;
42 jt->satb_mark_queue().enqueue(pre_val);
43 } else {
44 MutexLocker x(Shared_SATB_Q_lock);
45 JavaThread::satb_mark_queue_set().shared_satb_queue()->enqueue(pre_val);
46 }
47 }
49 // When we know the current java thread:
50 template <class T> void
51 G1SATBCardTableModRefBS::write_ref_field_pre_static(T* field,
52 oop new_val,
53 JavaThread* jt) {
54 if (!JavaThread::satb_mark_queue_set().active()) return;
55 T heap_oop = oopDesc::load_heap_oop(field);
56 if (!oopDesc::is_null(heap_oop)) {
57 oop pre_val = oopDesc::decode_heap_oop_not_null(heap_oop);
58 assert(pre_val->is_oop(true /* ignore mark word */), "Error");
59 jt->satb_mark_queue().enqueue(pre_val);
60 }
61 }
63 template <class T> void
64 G1SATBCardTableModRefBS::write_ref_array_pre_work(T* dst, int count) {
65 if (!JavaThread::satb_mark_queue_set().active()) return;
66 T* elem_ptr = dst;
67 for (int i = 0; i < count; i++, elem_ptr++) {
68 T heap_oop = oopDesc::load_heap_oop(elem_ptr);
69 if (!oopDesc::is_null(heap_oop)) {
70 enqueue(oopDesc::decode_heap_oop_not_null(heap_oop));
71 }
72 }
73 }
75 G1SATBCardTableLoggingModRefBS::
76 G1SATBCardTableLoggingModRefBS(MemRegion whole_heap,
77 int max_covered_regions) :
78 G1SATBCardTableModRefBS(whole_heap, max_covered_regions),
79 _dcqs(JavaThread::dirty_card_queue_set())
80 {
81 _kind = G1SATBCTLogging;
82 }
84 void
85 G1SATBCardTableLoggingModRefBS::write_ref_field_work(void* field,
86 oop new_val) {
87 jbyte* byte = byte_for(field);
88 if (*byte != dirty_card) {
89 *byte = dirty_card;
90 Thread* thr = Thread::current();
91 if (thr->is_Java_thread()) {
92 JavaThread* jt = (JavaThread*)thr;
93 jt->dirty_card_queue().enqueue(byte);
94 } else {
95 MutexLockerEx x(Shared_DirtyCardQ_lock,
96 Mutex::_no_safepoint_check_flag);
97 _dcqs.shared_dirty_card_queue()->enqueue(byte);
98 }
99 }
100 }
102 void
103 G1SATBCardTableLoggingModRefBS::write_ref_field_static(void* field,
104 oop new_val) {
105 uintptr_t field_uint = (uintptr_t)field;
106 uintptr_t new_val_uint = (uintptr_t)new_val;
107 uintptr_t comb = field_uint ^ new_val_uint;
108 comb = comb >> HeapRegion::LogOfHRGrainBytes;
109 if (comb == 0) return;
110 if (new_val == NULL) return;
111 // Otherwise, log it.
112 G1SATBCardTableLoggingModRefBS* g1_bs =
113 (G1SATBCardTableLoggingModRefBS*)Universe::heap()->barrier_set();
114 g1_bs->write_ref_field_work(field, new_val);
115 }
117 void
118 G1SATBCardTableLoggingModRefBS::invalidate(MemRegion mr, bool whole_heap) {
119 jbyte* byte = byte_for(mr.start());
120 jbyte* last_byte = byte_for(mr.last());
121 Thread* thr = Thread::current();
122 if (whole_heap) {
123 while (byte <= last_byte) {
124 *byte = dirty_card;
125 byte++;
126 }
127 } else {
128 // Enqueue if necessary.
129 if (thr->is_Java_thread()) {
130 JavaThread* jt = (JavaThread*)thr;
131 while (byte <= last_byte) {
132 if (*byte != dirty_card) {
133 *byte = dirty_card;
134 jt->dirty_card_queue().enqueue(byte);
135 }
136 byte++;
137 }
138 } else {
139 MutexLockerEx x(Shared_DirtyCardQ_lock,
140 Mutex::_no_safepoint_check_flag);
141 while (byte <= last_byte) {
142 if (*byte != dirty_card) {
143 *byte = dirty_card;
144 _dcqs.shared_dirty_card_queue()->enqueue(byte);
145 }
146 byte++;
147 }
148 }
149 }
150 }