--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/serial/markSweep.cpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,284 @@
+/*
+ * 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)