1 /* 2 * Copyright (c) 2016, 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_VM_GC_G1_G1CODECACHEREMSET_INTERNAL_HPP 25 #define SHARE_VM_GC_G1_G1CODECACHEREMSET_INTERNAL_HPP 26 27 #include "utilities/hashtable.hpp" 28 29 class G1CodeRootSetTable : public Hashtable<nmethod*, mtGC> { 30 friend class G1CodeRootSetTest; 31 typedef HashtableEntry<nmethod*, mtGC> Entry; 32 33 static G1CodeRootSetTable* volatile _purge_list; 34 35 G1CodeRootSetTable* _purge_next; 36 37 unsigned int compute_hash(nmethod* nm) { 38 uintptr_t hash = (uintptr_t)nm; 39 return hash ^ (hash >> 7); // code heap blocks are 128byte aligned 40 } 41 42 void remove_entry(Entry* e, Entry* previous); 43 Entry* new_entry(nmethod* nm); 44 45 public: 46 G1CodeRootSetTable(int size) : Hashtable<nmethod*, mtGC>(size, sizeof(Entry)), _purge_next(NULL) {} 47 ~G1CodeRootSetTable(); 48 49 // Needs to be protected by locks 50 bool add(nmethod* nm); 51 bool remove(nmethod* nm); 52 53 // Can be called without locking 54 bool contains(nmethod* nm); 55 56 int entry_size() const { return BasicHashtable<mtGC>::entry_size(); } 57 58 void copy_to(G1CodeRootSetTable* new_table); 59 void nmethods_do(CodeBlobClosure* blk); 60 61 template<typename CB> 62 int remove_if(CB& should_remove); 63 64 static void purge_list_append(G1CodeRootSetTable* tbl); 65 static void purge(); 66 67 static size_t static_mem_size() { 68 return sizeof(_purge_list); 69 } 70 71 size_t mem_size(); 72 }; 73 74 #endif /* SHARE_VM_GC_G1_G1CODECACHEREMSET_INTERNAL_HPP */