1 /*
  2  * Copyright (c) 2018, 2020, 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_GC_SHARED_WEAKPROCESSOR_INLINE_HPP
 26 #define SHARE_GC_SHARED_WEAKPROCESSOR_INLINE_HPP
 27 
 28 #include "gc/shared/weakProcessor.hpp"
 29 
 30 #include "classfile/stringTable.hpp"
 31 #include "gc/shared/oopStorage.inline.hpp"
 32 #include "gc/shared/oopStorageParState.inline.hpp"
 33 #include "gc/shared/oopStorageSet.hpp"
 34 #include "gc/shared/weakProcessorTimes.hpp"
 35 #include "gc/shared/workgroup.hpp"
 36 #include "prims/resolvedMethodTable.hpp"
 37 #include "utilities/debug.hpp"
 38 #include "utilities/enumIterator.hpp"
 39 
 40 class BoolObjectClosure;
 41 class OopClosure;
 42 
 43 template <typename IsAlive, typename KeepAlive>
 44 class WeakProcessor::CountingClosure : public Closure {
 45   IsAlive* _is_alive;
 46   KeepAlive* _keep_alive;
 47   size_t _old_dead;
 48   size_t _new_dead;
 49   size_t _live;
 50 
 51 public:
 52   CountingClosure(IsAlive* is_alive, KeepAlive* keep_alive) :
 53     _is_alive(is_alive),
 54     _keep_alive(keep_alive),
 55     _old_dead(0),
 56     _new_dead(0),
 57     _live(0)
 58   {}
 59 
 60   void do_oop(oop* p) {
 61     oop obj = *p;
 62     if (obj == NULL) {
 63       ++_old_dead;
 64     } else if (_is_alive->do_object_b(obj)) {
 65       _keep_alive->do_oop(p);
 66       ++_live;
 67     } else {
 68       *p = NULL;
 69       ++_new_dead;
 70     }
 71   }
 72 
 73   size_t dead() const { return _old_dead + _new_dead; }
 74   size_t new_dead() const { return _new_dead; }
 75   size_t total() const { return dead() + _live; }
 76 };
 77 
 78 template<typename IsAlive, typename KeepAlive>
 79 void WeakProcessor::Task::work(uint worker_id,
 80                                IsAlive* is_alive,
 81                                KeepAlive* keep_alive) {
 82   assert(worker_id < _nworkers,
 83          "worker_id (%u) exceeds task's configured workers (%u)",
 84          worker_id, _nworkers);
 85 
 86   for (auto id : EnumRange<OopStorageSet::WeakId>()) {
 87     CountingClosure<IsAlive, KeepAlive> cl(is_alive, keep_alive);
 88     WeakProcessorParTimeTracker pt(_times, id, worker_id);
 89     StorageState* cur_state = _storage_states.par_state(id);
 90     assert(cur_state->storage() == OopStorageSet::storage(id), "invariant");
 91     cur_state->oops_do(&cl);
 92     cur_state->increment_num_dead(cl.dead());
 93     if (_times != NULL) {
 94       _times->record_worker_items(worker_id, id, cl.new_dead(), cl.total());
 95     }
 96   }
 97 }
 98 
 99 class WeakProcessor::GangTask : public AbstractGangTask {
100   Task _task;
101   BoolObjectClosure* _is_alive;
102   OopClosure* _keep_alive;
103   void (*_erased_do_work)(GangTask* task, uint worker_id);
104 
105   template<typename IsAlive, typename KeepAlive>
106   static void erased_do_work(GangTask* task, uint worker_id) {
107     task->_task.work(worker_id,
108                      static_cast<IsAlive*>(task->_is_alive),
109                      static_cast<KeepAlive*>(task->_keep_alive));
110   }
111 
112 public:
113   template<typename IsAlive, typename KeepAlive>
114   GangTask(const char* name,
115            IsAlive* is_alive,
116            KeepAlive* keep_alive,
117            WeakProcessorTimes* times,
118            uint nworkers) :
119     AbstractGangTask(name),
120     _task(times, nworkers),
121     _is_alive(is_alive),
122     _keep_alive(keep_alive),
123     _erased_do_work(&erased_do_work<IsAlive, KeepAlive>)
124   {}
125 
126   virtual void work(uint worker_id);
127   void report_num_dead() { _task.report_num_dead(); }
128 };
129 
130 template<typename IsAlive, typename KeepAlive>
131 void WeakProcessor::weak_oops_do(WorkGang* workers,
132                                  IsAlive* is_alive,
133                                  KeepAlive* keep_alive,
134                                  WeakProcessorTimes* times) {
135   WeakProcessorTimeTracker tt(times);
136 
137   uint nworkers = ergo_workers(MIN2(workers->total_workers(),
138                                     times->max_threads()));
139 
140   GangTask task("Weak Processor", is_alive, keep_alive, times, nworkers);
141   workers->run_task(&task, nworkers);
142   task.report_num_dead();
143 }
144 
145 template<typename IsAlive, typename KeepAlive>
146 void WeakProcessor::weak_oops_do(WorkGang* workers,
147                                  IsAlive* is_alive,
148                                  KeepAlive* keep_alive,
149                                  uint indent_log) {
150   uint nworkers = ergo_workers(workers->total_workers());
151   WeakProcessorTimes times(nworkers);
152   weak_oops_do(workers, is_alive, keep_alive, &times);
153   times.log_subtotals(indent_log); // Caller logs total if desired.
154 }
155 
156 #endif // SHARE_GC_SHARED_WEAKPROCESSOR_INLINE_HPP