| /* |
| * Copyright (c) 1997, 2017, 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/serial/markSweep.inline.hpp" |
| #include "gc/shared/collectedHeap.inline.hpp" |
| #include "gc/shared/gcTimer.hpp" |
| #include "gc/shared/gcTrace.hpp" |
| #include "gc/shared/specialized_oop_closures.hpp" |
| #include "memory/iterator.inline.hpp" |
| #include "oops/instanceClassLoaderKlass.inline.hpp" |
| #include "oops/instanceKlass.inline.hpp" |
| #include "oops/instanceMirrorKlass.inline.hpp" |
| #include "oops/instanceRefKlass.inline.hpp" |
| #include "oops/methodData.hpp" |
| #include "oops/objArrayKlass.inline.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "oops/typeArrayOop.inline.hpp" |
| #include "utilities/macros.hpp" |
| #include "utilities/stack.inline.hpp" |
| #if INCLUDE_ALL_GCS |
| #include "gc/g1/g1StringDedup.hpp" |
| #endif // INCLUDE_ALL_GCS |
| |
| uint MarkSweep::_total_invocations = 0; |
| |
| Stack<oop, mtGC> MarkSweep::_marking_stack; |
| Stack<ObjArrayTask, mtGC> MarkSweep::_objarray_stack; |
| |
| Stack<oop, mtGC> MarkSweep::_preserved_oop_stack; |
| Stack<markOop, mtGC> 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; |
| |
| MarkAndPushClosure MarkSweep::mark_and_push_closure; |
| CLDToOopClosure MarkSweep::follow_cld_closure(&mark_and_push_closure); |
| CLDToOopClosure MarkSweep::adjust_cld_closure(&adjust_pointer_closure); |
| |
| inline void MarkSweep::mark_object(oop obj) { |
| #if INCLUDE_ALL_GCS |
| if (G1StringDedup::is_enabled()) { |
| // We must enqueue the object before it is marked |
| // as we otherwise can't read the object's age. |
| G1StringDedup::enqueue_from_mark(obj); |
| } |
| #endif |
| // some marks may contain information we need to preserve so we store them away |
| // and overwrite the mark. We'll restore it at the end of markSweep. |
| markOop mark = obj->mark(); |
| obj->set_mark(markOopDesc::prototype()->set_marked()); |
| |
| if (mark->must_be_preserved(obj)) { |
| preserve_mark(obj, mark); |
| } |
| } |
| |
| template <class T> inline void MarkSweep::mark_and_push(T* p) { |
| T heap_oop = oopDesc::load_heap_oop(p); |
| if (!oopDesc::is_null(heap_oop)) { |
| oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); |
| if (!obj->mark()->is_marked() && |
| !is_closed_archive_object(obj)) { |
| mark_object(obj); |
| _marking_stack.push(obj); |
| } |
| } |
| } |
| |
| inline void MarkSweep::follow_klass(Klass* klass) { |
| oop op = klass->klass_holder(); |
| MarkSweep::mark_and_push(&op); |
| } |
| |
| inline void MarkSweep::follow_cld(ClassLoaderData* cld) { |
| MarkSweep::follow_cld_closure.do_cld(cld); |
| } |
| |
| template <typename T> |
| inline void MarkAndPushClosure::do_oop_nv(T* p) { MarkSweep::mark_and_push(p); } |
| void MarkAndPushClosure::do_oop(oop* p) { do_oop_nv(p); } |
| void MarkAndPushClosure::do_oop(narrowOop* p) { do_oop_nv(p); } |
| inline bool MarkAndPushClosure::do_metadata_nv() { return true; } |
| bool MarkAndPushClosure::do_metadata() { return do_metadata_nv(); } |
| inline void MarkAndPushClosure::do_klass_nv(Klass* k) { MarkSweep::follow_klass(k); } |
| void MarkAndPushClosure::do_klass(Klass* k) { do_klass_nv(k); } |
| inline void MarkAndPushClosure::do_cld_nv(ClassLoaderData* cld) { MarkSweep::follow_cld(cld); } |
| void MarkAndPushClosure::do_cld(ClassLoaderData* cld) { do_cld_nv(cld); } |
| |
| template <class T> inline void MarkSweep::KeepAliveClosure::do_oop_work(T* p) { |
| mark_and_push(p); |
| } |
| |
| void MarkSweep::push_objarray(oop obj, size_t index) { |
| ObjArrayTask task(obj, index); |
| assert(task.is_valid(), "bad ObjArrayTask"); |
| _objarray_stack.push(task); |
| } |
| |
| inline void MarkSweep::follow_array(objArrayOop array) { |
| MarkSweep::follow_klass(array->klass()); |
| // Don't push empty arrays to avoid unnecessary work. |
| if (array->length() > 0) { |
| MarkSweep::push_objarray(array, 0); |
| } |
| } |
| |
| inline void MarkSweep::follow_object(oop obj) { |
| assert(obj->is_gc_marked(), "should be marked"); |
| if (obj->is_objArray()) { |
| // Handle object arrays explicitly to allow them to |
| // be split into chunks if needed. |
| MarkSweep::follow_array((objArrayOop)obj); |
| } else { |
| obj->oop_iterate(&mark_and_push_closure); |
| } |
| } |
| |
| void MarkSweep::follow_array_chunk(objArrayOop array, int index) { |
| const int len = array->length(); |
| const int beg_index = index; |
| assert(beg_index < len || len == 0, "index too large"); |
| |
| const int stride = MIN2(len - beg_index, (int) ObjArrayMarkingStride); |
| const int end_index = beg_index + stride; |
| |
| array->oop_iterate_range(&mark_and_push_closure, beg_index, end_index); |
| |
| if (end_index < len) { |
| MarkSweep::push_objarray(array, end_index); // Push the continuation. |
| } |
| } |
| |
| void MarkSweep::follow_stack() { |
| do { |
| while (!_marking_stack.is_empty()) { |
| oop obj = _marking_stack.pop(); |
| assert (obj->is_gc_marked(), "p must be marked"); |
| follow_object(obj); |
| } |
| // Process ObjArrays one at a time to avoid marking stack bloat. |
| if (!_objarray_stack.is_empty()) { |
| ObjArrayTask task = _objarray_stack.pop(); |
| follow_array_chunk(objArrayOop(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(); } |
| |
| template <class T> inline void MarkSweep::follow_root(T* p) { |
| assert(!Universe::heap()->is_in_reserved(p), |
| "roots shouldn't be things within the heap"); |
| T heap_oop = oopDesc::load_heap_oop(p); |
| if (!oopDesc::is_null(heap_oop)) { |
| oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); |
| if (!obj->mark()->is_marked() && |
| !is_closed_archive_object(obj)) { |
| mark_object(obj); |
| follow_object(obj); |
| } |
| } |
| follow_stack(); |
| } |
| |
| void MarkSweep::FollowRootClosure::do_oop(oop* p) { follow_root(p); } |
| void MarkSweep::FollowRootClosure::do_oop(narrowOop* p) { follow_root(p); } |
| |
| void PreservedMark::adjust_pointer() { |
| MarkSweep::adjust_pointer(&_obj); |
| } |
| |
| void PreservedMark::restore() { |
| _obj->set_mark(_mark); |
| } |
| |
| // 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); |
| } |
| } |
| |
| void MarkSweep::set_ref_processor(ReferenceProcessor* rp) { |
| _ref_processor = rp; |
| mark_and_push_closure.set_ref_processor(_ref_processor); |
| } |
| |
| AdjustPointerClosure MarkSweep::adjust_pointer_closure; |
| |
| template <typename T> |
| void AdjustPointerClosure::do_oop_nv(T* p) { MarkSweep::adjust_pointer(p); } |
| void AdjustPointerClosure::do_oop(oop* p) { do_oop_nv(p); } |
| void AdjustPointerClosure::do_oop(narrowOop* p) { do_oop_nv(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<oop, mtGC> 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"); |
| log_trace(gc)("Restoring " SIZE_FORMAT " 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() || is_closed_archive_object(p); } |
| |
| 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(); |
| } |
| |
| // Generate MS specialized oop_oop_iterate functions. |
| SPECIALIZED_OOP_OOP_ITERATE_CLOSURES_MS(ALL_KLASS_OOP_OOP_ITERATE_DEFN) |