Mercurial > hg > truffle
comparison src/share/vm/gc_implementation/g1/g1RegionToSpaceMapper.cpp @ 20337:1f1d373cd044
8038423: G1: Decommit memory within heap
Summary: Allow G1 to decommit memory of arbitrary regions within the heap and their associated auxiliary data structures card table, BOT, hot card cache, and mark bitmaps.
Reviewed-by: mgerdin, brutisso, jwilhelm
author | tschatzl |
---|---|
date | Thu, 21 Aug 2014 11:47:10 +0200 |
parents | |
children | 7b2fc3129653 |
comparison
equal
deleted
inserted
replaced
20336:6701abbc4441 | 20337:1f1d373cd044 |
---|---|
1 /* | |
2 * Copyright (c) 2001, 2013, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | |
20 * or visit www.oracle.com if you need additional information or have any | |
21 * questions. | |
22 * | |
23 */ | |
24 | |
25 #include "precompiled.hpp" | |
26 #include "gc_implementation/g1/g1BiasedArray.hpp" | |
27 #include "gc_implementation/g1/g1RegionToSpaceMapper.hpp" | |
28 #include "runtime/virtualspace.hpp" | |
29 #include "services/memTracker.hpp" | |
30 #include "utilities/bitMap.inline.hpp" | |
31 | |
32 G1RegionToSpaceMapper::G1RegionToSpaceMapper(ReservedSpace rs, | |
33 size_t commit_granularity, | |
34 size_t region_granularity, | |
35 MemoryType type) : | |
36 _storage(), | |
37 _commit_granularity(commit_granularity), | |
38 _region_granularity(region_granularity), | |
39 _listener(NULL), | |
40 _commit_map() { | |
41 guarantee(is_power_of_2(commit_granularity), "must be"); | |
42 guarantee(is_power_of_2(region_granularity), "must be"); | |
43 _storage.initialize_with_granularity(rs, commit_granularity); | |
44 | |
45 MemTracker::record_virtual_memory_type((address)rs.base(), type); | |
46 } | |
47 | |
48 // G1RegionToSpaceMapper implementation where the region granularity is larger than | |
49 // or the same as the commit granularity. | |
50 // Basically, the space corresponding to one region region spans several OS pages. | |
51 class G1RegionsLargerThanCommitSizeMapper : public G1RegionToSpaceMapper { | |
52 private: | |
53 size_t _pages_per_region; | |
54 | |
55 public: | |
56 G1RegionsLargerThanCommitSizeMapper(ReservedSpace rs, | |
57 size_t os_commit_granularity, | |
58 size_t alloc_granularity, | |
59 size_t commit_factor, | |
60 MemoryType type) : | |
61 G1RegionToSpaceMapper(rs, os_commit_granularity, alloc_granularity, type), | |
62 _pages_per_region(alloc_granularity / (os_commit_granularity * commit_factor)) { | |
63 | |
64 guarantee(alloc_granularity >= os_commit_granularity, "allocation granularity smaller than commit granularity"); | |
65 _commit_map.resize(rs.size() * commit_factor / alloc_granularity, /* in_resource_area */ false); | |
66 } | |
67 | |
68 virtual void commit_regions(uintptr_t start_idx, size_t num_regions) { | |
69 _storage.commit(start_idx * _pages_per_region, num_regions * _pages_per_region); | |
70 _commit_map.set_range(start_idx, start_idx + num_regions); | |
71 fire_on_commit(start_idx, num_regions); | |
72 } | |
73 | |
74 virtual void uncommit_regions(uintptr_t start_idx, size_t num_regions) { | |
75 _storage.uncommit(start_idx * _pages_per_region, num_regions * _pages_per_region); | |
76 _commit_map.clear_range(start_idx, start_idx + num_regions); | |
77 } | |
78 }; | |
79 | |
80 // G1RegionToSpaceMapper implementation where the region granularity is smaller | |
81 // than the commit granularity. | |
82 // Basically, the contents of one OS page span several regions. | |
83 class G1RegionsSmallerThanCommitSizeMapper : public G1RegionToSpaceMapper { | |
84 private: | |
85 class CommitRefcountArray : public G1BiasedMappedArray<uint> { | |
86 protected: | |
87 virtual uint default_value() const { return 0; } | |
88 }; | |
89 | |
90 size_t _regions_per_page; | |
91 | |
92 CommitRefcountArray _refcounts; | |
93 | |
94 uintptr_t region_idx_to_page_idx(uint region) const { | |
95 return region / _regions_per_page; | |
96 } | |
97 | |
98 public: | |
99 G1RegionsSmallerThanCommitSizeMapper(ReservedSpace rs, | |
100 size_t os_commit_granularity, | |
101 size_t alloc_granularity, | |
102 size_t commit_factor, | |
103 MemoryType type) : | |
104 G1RegionToSpaceMapper(rs, os_commit_granularity, alloc_granularity, type), | |
105 _regions_per_page((os_commit_granularity * commit_factor) / alloc_granularity), _refcounts() { | |
106 | |
107 guarantee((os_commit_granularity * commit_factor) >= alloc_granularity, "allocation granularity smaller than commit granularity"); | |
108 _refcounts.initialize((HeapWord*)rs.base(), (HeapWord*)(rs.base() + rs.size()), os_commit_granularity); | |
109 _commit_map.resize(rs.size() * commit_factor / alloc_granularity, /* in_resource_area */ false); | |
110 } | |
111 | |
112 virtual void commit_regions(uintptr_t start_idx, size_t num_regions) { | |
113 for (uintptr_t i = start_idx; i < start_idx + num_regions; i++) { | |
114 assert(!_commit_map.at(i), err_msg("Trying to commit storage at region "INTPTR_FORMAT" that is already committed", i)); | |
115 uintptr_t idx = region_idx_to_page_idx(i); | |
116 uint old_refcount = _refcounts.get_by_index(idx); | |
117 if (old_refcount == 0) { | |
118 _storage.commit(idx, 1); | |
119 } | |
120 _refcounts.set_by_index(idx, old_refcount + 1); | |
121 _commit_map.set_bit(i); | |
122 fire_on_commit(i, 1); | |
123 } | |
124 } | |
125 | |
126 virtual void uncommit_regions(uintptr_t start_idx, size_t num_regions) { | |
127 for (uintptr_t i = start_idx; i < start_idx + num_regions; i++) { | |
128 assert(_commit_map.at(i), err_msg("Trying to uncommit storage at region "INTPTR_FORMAT" that is not committed", i)); | |
129 uintptr_t idx = region_idx_to_page_idx(i); | |
130 uint old_refcount = _refcounts.get_by_index(idx); | |
131 assert(old_refcount > 0, "must be"); | |
132 if (old_refcount == 1) { | |
133 _storage.uncommit(idx, 1); | |
134 } | |
135 _refcounts.set_by_index(idx, old_refcount - 1); | |
136 _commit_map.clear_bit(i); | |
137 } | |
138 } | |
139 }; | |
140 | |
141 void G1RegionToSpaceMapper::fire_on_commit(uint start_idx, size_t num_regions) { | |
142 if (_listener != NULL) { | |
143 _listener->on_commit(start_idx, num_regions); | |
144 } | |
145 } | |
146 | |
147 G1RegionToSpaceMapper* G1RegionToSpaceMapper::create_mapper(ReservedSpace rs, | |
148 size_t os_commit_granularity, | |
149 size_t region_granularity, | |
150 size_t commit_factor, | |
151 MemoryType type) { | |
152 | |
153 if (region_granularity >= (os_commit_granularity * commit_factor)) { | |
154 return new G1RegionsLargerThanCommitSizeMapper(rs, os_commit_granularity, region_granularity, commit_factor, type); | |
155 } else { | |
156 return new G1RegionsSmallerThanCommitSizeMapper(rs, os_commit_granularity, region_granularity, commit_factor, type); | |
157 } | |
158 } |