/* * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #include "precompiled.hpp" #include "compiler/compileBroker.hpp" #include "gc_implementation/shared/gcTimer.hpp" #include "gc_implementation/shared/gcTrace.hpp" #include "gc_implementation/shared/markSweep.inline.hpp" #include "gc_interface/collectedHeap.inline.hpp" #include "oops/methodData.hpp" #include "oops/objArrayKlass.inline.hpp" #include "oops/oop.inline.hpp" PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC uint MarkSweep::_total_invocations = 0; Stack MarkSweep::_marking_stack; Stack MarkSweep::_objarray_stack; Stack MarkSweep::_preserved_oop_stack; Stack MarkSweep::_preserved_mark_stack; size_t MarkSweep::_preserved_count = 0; size_t MarkSweep::_preserved_count_max = 0; PreservedMark* MarkSweep::_preserved_marks = NULL; ReferenceProcessor* MarkSweep::_ref_processor = NULL; STWGCTimer* MarkSweep::_gc_timer = NULL; SerialOldTracer* MarkSweep::_gc_tracer = NULL; MarkSweep::FollowRootClosure MarkSweep::follow_root_closure; void MarkSweep::FollowRootClosure::do_oop(oop* p) { follow_root(p); } void MarkSweep::FollowRootClosure::do_oop(narrowOop* p) { follow_root(p); } MarkSweep::MarkAndPushClosure MarkSweep::mark_and_push_closure; MarkSweep::FollowKlassClosure MarkSweep::follow_klass_closure; MarkSweep::AdjustKlassClosure MarkSweep::adjust_klass_closure; void MarkSweep::MarkAndPushClosure::do_oop(oop* p) { mark_and_push(p); } void MarkSweep::MarkAndPushClosure::do_oop(narrowOop* p) { mark_and_push(p); } void MarkSweep::FollowKlassClosure::do_klass(Klass* klass) { klass->oops_do(&MarkSweep::mark_and_push_closure); } void MarkSweep::AdjustKlassClosure::do_klass(Klass* klass) { klass->oops_do(&MarkSweep::adjust_pointer_closure); } void MarkSweep::follow_class_loader(ClassLoaderData* cld) { cld->oops_do(&MarkSweep::mark_and_push_closure, &MarkSweep::follow_klass_closure, true); } void MarkSweep::follow_stack() { do { while (!_marking_stack.is_empty()) { oop obj = _marking_stack.pop(); assert (obj->is_gc_marked(), "p must be marked"); obj->follow_contents(); } // Process ObjArrays one at a time to avoid marking stack bloat. if (!_objarray_stack.is_empty()) { ObjArrayTask task = _objarray_stack.pop(); ObjArrayKlass* k = (ObjArrayKlass*)task.obj()->klass(); k->oop_follow_contents(task.obj(), task.index()); } } while (!_marking_stack.is_empty() || !_objarray_stack.is_empty()); } MarkSweep::FollowStackClosure MarkSweep::follow_stack_closure; void MarkSweep::FollowStackClosure::do_void() { follow_stack(); } // We preserve the mark which should be replaced at the end and the location // that it will go. Note that the object that this markOop belongs to isn't // currently at that address but it will be after phase4 void MarkSweep::preserve_mark(oop obj, markOop mark) { // We try to store preserved marks in the to space of the new generation since // this is storage which should be available. Most of the time this should be // sufficient space for the marks we need to preserve but if it isn't we fall // back to using Stacks to keep track of the overflow. if (_preserved_count < _preserved_count_max) { _preserved_marks[_preserved_count++].init(obj, mark); } else { _preserved_mark_stack.push(mark); _preserved_oop_stack.push(obj); } } MarkSweep::AdjustPointerClosure MarkSweep::adjust_pointer_closure; void MarkSweep::AdjustPointerClosure::do_oop(oop* p) { adjust_pointer(p); } void MarkSweep::AdjustPointerClosure::do_oop(narrowOop* p) { adjust_pointer(p); } void MarkSweep::adjust_marks() { assert( _preserved_oop_stack.size() == _preserved_mark_stack.size(), "inconsistent preserved oop stacks"); // adjust the oops we saved earlier for (size_t i = 0; i < _preserved_count; i++) { _preserved_marks[i].adjust_pointer(); } // deal with the overflow stack StackIterator iter(_preserved_oop_stack); while (!iter.is_empty()) { oop* p = iter.next_addr(); adjust_pointer(p); } } void MarkSweep::restore_marks() { assert(_preserved_oop_stack.size() == _preserved_mark_stack.size(), "inconsistent preserved oop stacks"); if (PrintGC && Verbose) { gclog_or_tty->print_cr("Restoring %d marks", _preserved_count + _preserved_oop_stack.size()); } // restore the marks we saved earlier for (size_t i = 0; i < _preserved_count; i++) { _preserved_marks[i].restore(); } // deal with the overflow while (!_preserved_oop_stack.is_empty()) { oop obj = _preserved_oop_stack.pop(); markOop mark = _preserved_mark_stack.pop(); obj->set_mark(mark); } } MarkSweep::IsAliveClosure MarkSweep::is_alive; bool MarkSweep::IsAliveClosure::do_object_b(oop p) { return p->is_gc_marked(); } MarkSweep::KeepAliveClosure MarkSweep::keep_alive; void MarkSweep::KeepAliveClosure::do_oop(oop* p) { MarkSweep::KeepAliveClosure::do_oop_work(p); } void MarkSweep::KeepAliveClosure::do_oop(narrowOop* p) { MarkSweep::KeepAliveClosure::do_oop_work(p); } void marksweep_init() { MarkSweep::_gc_timer = new (ResourceObj::C_HEAP, mtGC) STWGCTimer(); MarkSweep::_gc_tracer = new (ResourceObj::C_HEAP, mtGC) SerialOldTracer(); } #ifndef PRODUCT void MarkSweep::trace(const char* msg) { if (TraceMarkSweep) gclog_or_tty->print("%s", msg); } #endif