1 /*
2 * Copyright (c) 2001, 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.
22 *
23 */
24
25 #ifndef SHARE_VM_GC_SERIAL_TENUREDGENERATION_HPP
26 #define SHARE_VM_GC_SERIAL_TENUREDGENERATION_HPP
27
28 #include "gc/serial/cSpaceCounters.hpp"
29 #include "gc/shared/cardGeneration.hpp"
30 #include "gc/shared/gcStats.hpp"
31 #include "gc/shared/generationCounters.hpp"
32 #include "utilities/macros.hpp"
33
34 // TenuredGeneration models the heap containing old (promoted/tenured) objects
35 // contained in a single contiguous space.
36 //
37 // Garbage collection is performed using mark-compact.
38
39 class TenuredGeneration: public CardGeneration {
40 friend class VMStructs;
41 // Abstractly, this is a subtype that gets access to protected fields.
42 friend class VM_PopulateDumpSharedSpace;
43
44 protected:
45 ContiguousSpace* _the_space; // Actual space holding objects
46
47 GenerationCounters* _gen_counters;
48 CSpaceCounters* _space_counters;
49
50 // Allocation failure
51 virtual bool expand(size_t bytes, size_t expand_bytes);
52
53 // Accessing spaces
54 ContiguousSpace* space() const { return _the_space; }
55
56 void assert_correct_size_change_locking();
57
58 public:
59 TenuredGeneration(ReservedSpace rs,
60 size_t initial_byte_size,
61 GenRemSet* remset);
62
63 Generation::Name kind() { return Generation::MarkSweepCompact; }
64
65 // Printing
66 const char* name() const { return "tenured generation"; }
67 const char* short_name() const { return "Tenured"; }
68
69 // Does a "full" (forced) collection invoked on this generation collect
70 // the young generation as well? Note that this is a hack to allow the
71 // collection of the young gen first if the flag is set.
72 virtual bool full_collects_young_generation() const {
73 return !ScavengeBeforeFullGC;
74 }
75
76 size_t unsafe_max_alloc_nogc() const;
77 size_t contiguous_available() const;
78
79 // Iteration
80 void object_iterate(ObjectClosure* blk);
81
82 virtual inline HeapWord* allocate(size_t word_size, bool is_tlab);
83 virtual inline HeapWord* par_allocate(size_t word_size, bool is_tlab);
84
85 #define TenuredGen_SINCE_SAVE_MARKS_DECL(OopClosureType, nv_suffix) \
86 void oop_since_save_marks_iterate##nv_suffix(OopClosureType* cl);
87 TenuredGen_SINCE_SAVE_MARKS_DECL(OopsInGenClosure,_v)
88 SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES(TenuredGen_SINCE_SAVE_MARKS_DECL)
89
90 void save_marks();
91 void reset_saved_marks();
92 bool no_allocs_since_save_marks();
93
94 inline size_t block_size(const HeapWord* addr) const;
95
96 inline bool block_is_obj(const HeapWord* addr) const;
97
98 virtual void collect(bool full,
99 bool clear_all_soft_refs,
100 size_t size,
101 bool is_tlab);
102
103 HeapWord* expand_and_allocate(size_t size,
104 bool is_tlab,
105 bool parallel = false);
106
107 virtual void prepare_for_verify();
108
109 virtual void gc_prologue(bool full);
110 virtual void gc_epilogue(bool full);
111
112 bool should_collect(bool full,
113 size_t word_size,
114 bool is_tlab);
115
116 virtual void compute_new_size();
117
118 // Performance Counter support
119 void update_counters();
120
121 virtual void record_spaces_top();
122
123 // Statistics
124
125 virtual void update_gc_stats(Generation* current_generation, bool full);
126
127 virtual bool promotion_attempt_is_safe(size_t max_promoted_in_bytes) const;
128
129 virtual void verify();
130 virtual void print_on(outputStream* st) const;
131 };
132
133 #endif // SHARE_VM_GC_SERIAL_TENUREDGENERATION_HPP