1 /*
2 * Copyright (c) 2011, 2015, 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.
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23 */
24
25 #ifndef SHARE_VM_GC_G1_HEAPREGIONSET_HPP
26 #define SHARE_VM_GC_G1_HEAPREGIONSET_HPP
27
28 #include "gc/g1/heapRegion.hpp"
29
30 #define assert_heap_region_set(p, message) \
31 do { \
32 assert((p), "[%s] %s ln: %u cy: " SIZE_FORMAT, \
33 name(), message, length(), total_capacity_bytes()); \
34 } while (0)
35
36 #define guarantee_heap_region_set(p, message) \
37 do { \
38 guarantee((p), "[%s] %s ln: %u cy: " SIZE_FORMAT, \
39 name(), message, length(), total_capacity_bytes()); \
40 } while (0)
41
42 #define assert_free_region_list(p, message) \
43 do { \
44 assert((p), "[%s] %s ln: %u cy: " SIZE_FORMAT " hd: " PTR_FORMAT " tl: " PTR_FORMAT, \
45 name(), message, length(), total_capacity_bytes(), p2i(_head), p2i(_tail)); \
46 } while (0)
47
48
49 // Set verification will be forced either if someone defines
50 // HEAP_REGION_SET_FORCE_VERIFY to be 1, or in builds in which
51 // asserts are compiled in.
52 #ifndef HEAP_REGION_SET_FORCE_VERIFY
53 #define HEAP_REGION_SET_FORCE_VERIFY defined(ASSERT)
54 #endif // HEAP_REGION_SET_FORCE_VERIFY
55
56 class HRSMtSafeChecker : public CHeapObj<mtGC> {
57 public:
58 virtual void check() = 0;
59 };
60
61 class MasterFreeRegionListMtSafeChecker : public HRSMtSafeChecker { public: void check(); };
62 class SecondaryFreeRegionListMtSafeChecker : public HRSMtSafeChecker { public: void check(); };
63 class HumongousRegionSetMtSafeChecker : public HRSMtSafeChecker { public: void check(); };
64 class OldRegionSetMtSafeChecker : public HRSMtSafeChecker { public: void check(); };
65
66 // Base class for all the classes that represent heap region sets. It
67 // contains the basic attributes that each set needs to maintain
68 // (e.g., length, region num, used bytes sum) plus any shared
69 // functionality (e.g., verification).
70
71 class HeapRegionSetBase VALUE_OBJ_CLASS_SPEC {
72 friend class VMStructs;
73 private:
74 bool _is_humongous;
75 bool _is_free;
76 HRSMtSafeChecker* _mt_safety_checker;
77
78 protected:
79 // The number of regions in to the set.
80 uint _length;
81
82 const char* _name;
83
84 bool _verify_in_progress;
85
86 // verify_region() is used to ensure that the contents of a region
87 // added to / removed from a set are consistent.
88 void verify_region(HeapRegion* hr) PRODUCT_RETURN;
89
90 // Indicates whether all regions in the set should be humongous or
91 // not. Only used during verification.
92 bool regions_humongous() { return _is_humongous; }
93
94 // Indicates whether all regions in the set should be free or
95 // not. Only used during verification.
96 bool regions_free() { return _is_free; }
97
98 void check_mt_safety() {
99 if (_mt_safety_checker != NULL) {
100 _mt_safety_checker->check();
101 }
102 }
103
104 HeapRegionSetBase(const char* name, bool humongous, bool free, HRSMtSafeChecker* mt_safety_checker);
105
106 public:
107 const char* name() { return _name; }
108
109 uint length() const { return _length; }
110
111 bool is_empty() { return _length == 0; }
112
113 size_t total_capacity_bytes() {
114 return _length * HeapRegion::GrainBytes;
115 }
116
117 // It updates the fields of the set to reflect hr being added to
118 // the set and tags the region appropriately.
119 inline void add(HeapRegion* hr);
120
121 // It updates the fields of the set to reflect hr being removed
122 // from the set and tags the region appropriately.
123 inline void remove(HeapRegion* hr);
124
125 virtual void verify();
126 void verify_start();
127 void verify_next_region(HeapRegion* hr);
128 void verify_end();
129
130 #if HEAP_REGION_SET_FORCE_VERIFY
131 void verify_optional() {
132 verify();
133 }
134 #else // HEAP_REGION_SET_FORCE_VERIFY
135 void verify_optional() { }
136 #endif // HEAP_REGION_SET_FORCE_VERIFY
137
138 virtual void print_on(outputStream* out, bool print_contents = false);
139 };
140
141 #define hrs_assert_sets_match(_set1_, _set2_) \
142 do { \
143 assert(((_set1_)->regions_humongous() == (_set2_)->regions_humongous()) && \
144 ((_set1_)->regions_free() == (_set2_)->regions_free()), \
145 "the contents of set %s and set %s should match", \
146 (_set1_)->name(), \
147 (_set2_)->name()); \
148 } while (0)
149
150 // This class represents heap region sets whose members are not
151 // explicitly tracked. It's helpful to group regions using such sets
152 // so that we can reason about all the region groups in the heap using
153 // the same interface (namely, the HeapRegionSetBase API).
154
155 class HeapRegionSet : public HeapRegionSetBase {
156 public:
157 HeapRegionSet(const char* name, bool humongous, HRSMtSafeChecker* mt_safety_checker):
158 HeapRegionSetBase(name, humongous, false /* free */, mt_safety_checker) { }
159
160 void bulk_remove(const uint removed) {
161 _length -= removed;
162 }
163 };
164
165 // A set that links all the regions added to it in a doubly-linked
166 // sorted list. We should try to avoid doing operations that iterate over
167 // such lists in performance critical paths. Typically we should
168 // add / remove one region at a time or concatenate two lists.
169
170 class FreeRegionListIterator;
171
172 class FreeRegionList : public HeapRegionSetBase {
173 friend class FreeRegionListIterator;
174
175 private:
176 HeapRegion* _head;
177 HeapRegion* _tail;
178
179 // _last is used to keep track of where we added an element the last
180 // time. It helps to improve performance when adding several ordered items in a row.
181 HeapRegion* _last;
182
183 static uint _unrealistically_long_length;
184
185 inline HeapRegion* remove_from_head_impl();
186 inline HeapRegion* remove_from_tail_impl();
187
188 protected:
189 // See the comment for HeapRegionSetBase::clear()
190 virtual void clear();
191
192 public:
193 FreeRegionList(const char* name, HRSMtSafeChecker* mt_safety_checker = NULL):
194 HeapRegionSetBase(name, false /* humongous */, true /* empty */, mt_safety_checker) {
195 clear();
196 }
197
198 void verify_list();
199
200 #ifdef ASSERT
201 bool contains(HeapRegion* hr) const {
202 return hr->containing_set() == this;
203 }
204 #endif
205
206 static void set_unrealistically_long_length(uint len);
207
208 // Add hr to the list. The region should not be a member of another set.
209 // Assumes that the list is ordered and will preserve that order. The order
210 // is determined by hrm_index.
211 inline void add_ordered(HeapRegion* hr);
212
213 // Removes from head or tail based on the given argument.
214 HeapRegion* remove_region(bool from_head);
215
216 // Merge two ordered lists. The result is also ordered. The order is
217 // determined by hrm_index.
218 void add_ordered(FreeRegionList* from_list);
219
220 // It empties the list by removing all regions from it.
221 void remove_all();
222
223 // Remove all (contiguous) regions from first to first + num_regions -1 from
224 // this list.
225 // Num_regions must be > 1.
226 void remove_starting_at(HeapRegion* first, uint num_regions);
227
228 virtual void verify();
229
230 virtual void print_on(outputStream* out, bool print_contents = false);
231 };
232
233 // Iterator class that provides a convenient way to iterate over the
234 // regions of a FreeRegionList.
235
236 class FreeRegionListIterator : public StackObj {
237 private:
238 FreeRegionList* _list;
239 HeapRegion* _curr;
240
241 public:
242 bool more_available() {
243 return _curr != NULL;
244 }
245
246 HeapRegion* get_next() {
247 assert(more_available(),
248 "get_next() should be called when more regions are available");
249
250 // If we are going to introduce a count in the iterator we should
251 // do the "cycle" check.
252
253 HeapRegion* hr = _curr;
254 _list->verify_region(hr);
255 _curr = hr->next();
256 return hr;
257 }
258
259 FreeRegionListIterator(FreeRegionList* list) : _curr(NULL), _list(list) {
260 _curr = list->_head;
261 }
262 };
263
264 #endif // SHARE_VM_GC_G1_HEAPREGIONSET_HPP