1 /* 2 * Copyright (c) 2014, 2018, 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 #include "precompiled.hpp" 26 #include "classfile/stringTable.hpp" 27 #include "gc/shared/stringdedup/stringDedup.hpp" 28 #include "gc/shared/stringdedup/stringDedupQueue.hpp" 29 #include "gc/shared/stringdedup/stringDedupQueue.inline.hpp" 30 #include "gc/shared/stringdedup/stringDedupTable.hpp" 31 #include "gc/shared/stringdedup/stringDedupThread.hpp" 32 #include "gc/shared/suspendibleThreadSet.hpp" 33 #include "logging/log.hpp" 34 #include "oops/access.inline.hpp" 35 #include "oops/oop.inline.hpp" 36 #include "runtime/atomic.hpp" 37 38 StringDedupThread* StringDedupThread::_thread = NULL; 39 40 StringDedupThread::StringDedupThread() : 41 ConcurrentGCThread() { 42 set_name("StrDedup"); 43 create_and_start(); 44 } 45 46 StringDedupThread::~StringDedupThread() { 47 ShouldNotReachHere(); 48 } 49 50 StringDedupThread* StringDedupThread::thread() { 51 assert(_thread != NULL, "String deduplication thread not created"); 52 return _thread; 53 } 54 55 class StringDedupSharedClosure: public OopClosure { 56 private: 57 StringDedupStat* _stat; 58 59 public: 60 StringDedupSharedClosure(StringDedupStat* stat) : _stat(stat) {} 61 62 virtual void do_oop(narrowOop* p) { ShouldNotReachHere(); } 63 virtual void do_oop(oop* p) { 64 oop java_string = RawAccess<>::oop_load(p); 65 StringDedupTable::deduplicate(java_string, _stat); 66 } 67 }; 68 69 // The CDS archive does not include the string dedupication table. Only the string 70 // table is saved in the archive. The shared strings from CDS archive need to be 71 // added to the string dedupication table before deduplication occurs. That is 72 // done in the begining of the StringDedupThread (see StringDedupThread::do_deduplication()). 73 void StringDedupThread::deduplicate_shared_strings(StringDedupStat* stat) { 74 StringDedupSharedClosure sharedStringDedup(stat); 75 StringTable::shared_oops_do(&sharedStringDedup); 76 } 77 78 void StringDedupThread::pre_run() { 79 SuspendibleThreadSetJoiner sts_join; 80 ConcurrentGCThread::pre_run(); 81 } 82 83 void StringDedupThread::post_run() { 84 SuspendibleThreadSetJoiner sts_join; 85 ConcurrentGCThread::post_run(); 86 } 87 88 void StringDedupThread::stop_service() { 89 StringDedupQueue::cancel_wait(); 90 } 91 92 void StringDedupThread::print_start(const StringDedupStat* last_stat) { 93 StringDedupStat::print_start(last_stat); 94 } 95 96 void StringDedupThread::print_end(const StringDedupStat* last_stat, const StringDedupStat* total_stat) { 97 StringDedupStat::print_end(last_stat, total_stat); 98 if (log_is_enabled(Debug, gc, stringdedup)) { 99 last_stat->print_statistics(false); 100 total_stat->print_statistics(true); 101 102 StringDedupTable::print_statistics(); 103 StringDedupQueue::print_statistics(); 104 } 105 }