-
Notifications
You must be signed in to change notification settings - Fork 392
/
RememberedSetSATB.hpp
92 lines (80 loc) · 4.45 KB
/
RememberedSetSATB.hpp
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
/*******************************************************************************
* Copyright (c) 1991, 2019 IBM Corp. and others
*
* This program and the accompanying materials are made available under
* the terms of the Eclipse Public License 2.0 which accompanies this
* distribution and is available at https://www.eclipse.org/legal/epl-2.0/
* or the Apache License, Version 2.0 which accompanies this distribution and
* is available at https://www.apache.org/licenses/LICENSE-2.0.
*
* This Source Code may also be made available under the following
* Secondary Licenses when the conditions for such availability set
* forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
* General Public License, version 2 with the GNU Classpath
* Exception [1] and GNU General Public License, version 2 with the
* OpenJDK Assembly Exception [2].
*
* [1] https://www.gnu.org/software/classpath/license.html
* [2] http://openjdk.java.net/legal/assembly-exception.html
*
* SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0 WITH Classpath-exception-2.0 OR LicenseRef-GPL-2.0 WITH Assembly-exception
*******************************************************************************/
#if !defined(REMEMBEREDSETSATB_HPP_)
#define REMEMBEREDSETSATB_HPP_
#if defined(OMR_GC_REALTIME)
#include "WorkPacketsSATB.hpp"
#include "BaseNonVirtual.hpp"
class EnvironmentModron;
class MM_RememberedSetSATB : public MM_BaseNonVirtual
{
/* Data members & types */
public:
MM_GCRememberedSet _rememberedSetStruct; /**< The VM-readable struct containing the remembered set "global" indexes. */
protected:
private:
MM_WorkPacketsSATB *_workPackets; /**< The workPackets struct used as backing store for the rememberedSet */
/* Methods */
public:
/* Constructors & destructors */
static MM_RememberedSetSATB *newInstance(MM_EnvironmentBase *env, MM_WorkPacketsSATB *workPackets);
void kill(MM_EnvironmentBase *env);
MM_RememberedSetSATB(MM_EnvironmentBase *env, MM_WorkPacketsSATB *workPackets) :
MM_BaseNonVirtual(),
_workPackets(workPackets)
{
_typeId = __FUNCTION__;
/* Initializing the global fragment index to the reserved index means the GC starts
* with the barrier disabled. The preservedGlobalFragmentIndex must be initialized
* to any non-reserved value so that the call to MM_RealtimeGC::enableWriteBarrier which
* in turns restores the globalFragmentIndex from the preservedGlobalFragmentIndex actually
* restores a valid, non-reserved value.
*/
_rememberedSetStruct.globalFragmentIndex = J9GC_REMEMBERED_SET_RESERVED_INDEX;
_rememberedSetStruct.preservedGlobalFragmentIndex = J9GC_REMEMBERED_SET_RESERVED_INDEX + 1;
};
/* New methods */
void initializeFragment(MM_EnvironmentBase* env, MM_GCRememberedSetFragment* fragment); /* "Nulls" out a fragment. */
void storeInFragment(MM_EnvironmentBase* env, MM_GCRememberedSetFragment* fragment, UDATA* value); /* This guarantees the store will occur, but a new fragment may be fetched. */
bool isFragmentValid(MM_EnvironmentBase* env, const MM_GCRememberedSetFragment* fragment);
void preserveLocalFragmentIndex(MM_EnvironmentBase* env, MM_GCRememberedSetFragment* fragment); /* Called by the code that enables the double-barrier. */
void restoreLocalFragmentIndex(MM_EnvironmentBase* env, MM_GCRememberedSetFragment* fragment); /* Called by the root scanner to disable the double-barrier. */
void preserveGlobalFragmentIndex(MM_EnvironmentBase* env); /* Called by the code that disables the barrier. */
void restoreGlobalFragmentIndex(MM_EnvironmentBase* env); /* Called by the code that enables the barrier. */
/* Used to determine if the realtime write barrier is enabled. */
MMINLINE bool
isGlobalFragmentIndexPreserved(MM_EnvironmentBase* env = NULL)
{
return (J9GC_REMEMBERED_SET_RESERVED_INDEX == _rememberedSetStruct.globalFragmentIndex);
}
void flushFragments(MM_EnvironmentBase* env); /* Ensures all fragments will be seen as invalid next time they are accessed. */
bool refreshFragment(MM_EnvironmentBase *env, MM_GCRememberedSetFragment* fragment);
protected:
bool initialize(MM_EnvironmentBase *env);
void tearDown(MM_EnvironmentBase *env);
UDATA getLocalFragmentIndex(MM_EnvironmentBase* env, const MM_GCRememberedSetFragment* fragment);
UDATA getGlobalFragmentIndex(MM_EnvironmentBase* env);
private:
void setGlobalIndex(MM_EnvironmentBase* env, UDATA indexValue); /* Increments the appropriate global index (global or preserved). */
};
#endif /* defined(OMR_GC_REALTIME) */
#endif /* REMEMBEREDSETSATB_HPP_ */