1 /*
2  * Copyright (c) 2016, 2019, Red Hat, Inc. All rights reserved.
3  *
4  * This code is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License version 2 only, as
6  * published by the Free Software Foundation.
7  *
8  * This code is distributed in the hope that it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
11  * version 2 for more details (a copy is included in the LICENSE file that
12  * accompanied this code).
13  *
14  * You should have received a copy of the GNU General Public License version
15  * 2 along with this work; if not, write to the Free Software Foundation,
16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17  *
18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19  * or visit www.oracle.com if you need additional information or have any
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22  */
23 
24 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP
25 #define SHARE_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP
26 
27 #include "memory/allocation.hpp"
28 #include "gc/shenandoah/shenandoahHeap.hpp"
29 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
30 #include "gc/shenandoah/shenandoahPadding.hpp"
31 
32 class ShenandoahCollectionSet : public CHeapObj<mtGC> {
33   friend class ShenandoahHeap;
34 private:
35   size_t const          _map_size;
36   size_t const          _region_size_bytes_shift;
37   ReservedSpace         _map_space;
38   char* const           _cset_map;
39   // Bias cset map's base address for fast test if an oop is in cset
40   char* const           _biased_cset_map;
41 
42   ShenandoahHeap* const _heap;
43 
44   size_t                _garbage;
45   size_t                _used;
46   size_t                _region_count;
47 
48   shenandoah_padding(0);
49   volatile jint         _current_index;
50   shenandoah_padding(1);
51 
52 public:
53   ShenandoahCollectionSet(ShenandoahHeap* heap, char* heap_base, size_t size);
54 
55   // Add region to collection set
56   void add_region(ShenandoahHeapRegion* r);
57 
58   // MT version
59   ShenandoahHeapRegion* claim_next();
60 
61   // Single-thread version
62   ShenandoahHeapRegion* next();
63 
count() const64   size_t count()  const { return _region_count; }
is_empty() const65   bool is_empty() const { return _region_count == 0; }
66 
clear_current_index()67   void clear_current_index() {
68     _current_index = 0;
69   }
70 
71   inline bool is_in(ShenandoahHeapRegion* r) const;
72   inline bool is_in(size_t region_idx)       const;
73   inline bool is_in(oop obj)                 const;
74   inline bool is_in_loc(void* loc)           const;
75 
76   void print_on(outputStream* out) const;
77 
used() const78   size_t used()      const { return _used; }
garbage() const79   size_t garbage()   const { return _garbage;   }
80   void clear();
81 
82 private:
map_address() const83   char* map_address() const {
84     return _cset_map;
85   }
biased_map_address() const86   char* biased_map_address() const {
87     return _biased_cset_map;
88   }
89 };
90 
91 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP
92