Mercurial > jdk8-mips64-public > hotspot / file revision
src/share/vm/gc_implementation/parallelScavenge/psTasks.hpp@1fdb98a17101
src/share/vm/gc_implementation/parallelScavenge/psTasks.hpp
Sat, 19 Jul 2008 17:38:22 -0400
- author
- coleenp
- date
- Sat, 19 Jul 2008 17:38:22 -0400
- changeset 672
- 1fdb98a17101
- parent 435
- a61af66fc99e
- child 1424
- 148e5441d916
- permissions
- -rw-r--r--
6716785: implicit null checks not triggering with CompressedOops
Summary: allocate alignment-sized page(s) below java heap so that memory accesses at heap_base+1page give signal and cause an implicit null check
Reviewed-by: kvn, jmasa, phh, jcoomes
1 /*
2 * Copyright 2002-2005 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 //
26 // psTasks.hpp is a collection of GCTasks used by the
27 // parallelScavenge collector.
28 //
30 class GCTask;
31 class OopClosure;
32 class OopStack;
33 class ObjectStartArray;
34 class ParallelTaskTerminator;
35 class MutableSpace;
36 class PSOldGen;
37 class Thread;
38 class VMThread;
40 //
41 // ScavengeRootsTask
42 //
43 // This task scans all the roots of a given type.
44 //
45 //
47 class ScavengeRootsTask : public GCTask {
48 public:
49 enum RootType {
50 universe = 1,
51 jni_handles = 2,
52 threads = 3,
53 object_synchronizer = 4,
54 flat_profiler = 5,
55 system_dictionary = 6,
56 management = 7,
57 jvmti = 8
58 };
59 private:
60 RootType _root_type;
61 public:
62 ScavengeRootsTask(RootType value) : _root_type(value) {}
64 char* name() { return (char *)"scavenge-roots-task"; }
66 virtual void do_it(GCTaskManager* manager, uint which);
67 };
69 //
70 // ThreadRootsTask
71 //
72 // This task scans the roots of a single thread. This task
73 // enables scanning of thread roots in parallel.
74 //
76 class ThreadRootsTask : public GCTask {
77 private:
78 JavaThread* _java_thread;
79 VMThread* _vm_thread;
80 public:
81 ThreadRootsTask(JavaThread* root) : _java_thread(root), _vm_thread(NULL) {}
82 ThreadRootsTask(VMThread* root) : _java_thread(NULL), _vm_thread(root) {}
84 char* name() { return (char *)"thread-roots-task"; }
86 virtual void do_it(GCTaskManager* manager, uint which);
87 };
89 //
90 // StealTask
91 //
92 // This task is used to distribute work to idle threads.
93 //
95 class StealTask : public GCTask {
96 private:
97 ParallelTaskTerminator* const _terminator;
98 public:
99 char* name() { return (char *)"steal-task"; }
101 StealTask(ParallelTaskTerminator* t);
103 ParallelTaskTerminator* terminator() { return _terminator; }
105 virtual void do_it(GCTaskManager* manager, uint which);
106 };
108 //
109 // SerialOldToYoungRootsTask
110 //
111 // This task is used to scan for roots in the perm gen
113 class SerialOldToYoungRootsTask : public GCTask {
114 private:
115 PSOldGen* _gen;
116 HeapWord* _gen_top;
118 public:
119 SerialOldToYoungRootsTask(PSOldGen *gen, HeapWord* gen_top) :
120 _gen(gen), _gen_top(gen_top) { }
122 char* name() { return (char *)"serial-old-to-young-roots-task"; }
124 virtual void do_it(GCTaskManager* manager, uint which);
125 };
127 //
128 // OldToYoungRootsTask
129 //
130 // This task is used to scan old to young roots in parallel
132 class OldToYoungRootsTask : public GCTask {
133 private:
134 PSOldGen* _gen;
135 HeapWord* _gen_top;
136 uint _stripe_number;
138 public:
139 OldToYoungRootsTask(PSOldGen *gen, HeapWord* gen_top, uint stripe_number) :
140 _gen(gen), _gen_top(gen_top), _stripe_number(stripe_number) { }
142 char* name() { return (char *)"old-to-young-roots-task"; }
144 virtual void do_it(GCTaskManager* manager, uint which);
145 };
