1/*
2 * Copyright (c) 2016, 2019, 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#ifndef SHARE_GC_G1_G1CODEROOTSETTABLE_HPP
25#define SHARE_GC_G1_G1CODEROOTSETTABLE_HPP
26
27#include "utilities/hashtable.hpp"
28
29class nmethod;
30
31class G1CodeRootSetTable : public Hashtable<nmethod*, mtGC> {
32 friend class G1CodeRootSetTest;
33 typedef HashtableEntry<nmethod*, mtGC> Entry;
34
35 static G1CodeRootSetTable* volatile _purge_list;
36
37 G1CodeRootSetTable* _purge_next;
38
39 unsigned int compute_hash(nmethod* nm) {
40 uintptr_t hash = (uintptr_t)nm;
41 return hash ^ (hash >> 7); // code heap blocks are 128byte aligned
42 }
43
44 void remove_entry(Entry* e, Entry* previous);
45 Entry* new_entry(nmethod* nm);
46
47 public:
48 G1CodeRootSetTable(int size) : Hashtable<nmethod*, mtGC>(size, sizeof(Entry)), _purge_next(NULL) {}
49 ~G1CodeRootSetTable();
50
51 // Needs to be protected by locks
52 bool add(nmethod* nm);
53 bool remove(nmethod* nm);
54
55 // Can be called without locking
56 bool contains(nmethod* nm);
57
58 int entry_size() const { return BasicHashtable<mtGC>::entry_size(); }
59
60 void copy_to(G1CodeRootSetTable* new_table);
61 void nmethods_do(CodeBlobClosure* blk);
62
63 template<typename CB>
64 int remove_if(CB& should_remove);
65
66 static void purge_list_append(G1CodeRootSetTable* tbl);
67 static void purge();
68
69 static size_t static_mem_size() {
70 return sizeof(_purge_list);
71 }
72
73 size_t mem_size();
74};
75
76#endif // SHARE_GC_G1_G1CODEROOTSETTABLE_HPP
77