--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/gc/parallel/psScavenge.hpp Wed May 13 15:16:06 2015 +0200
@@ -0,0 +1,166 @@
+/*
+ * Copyright (c) 2002, 2015, 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.
+ *
+ */
+
+#ifndef SHARE_VM_GC_PARALLEL_PSSCAVENGE_HPP
+#define SHARE_VM_GC_PARALLEL_PSSCAVENGE_HPP
+
+#include "gc/parallel/cardTableExtension.hpp"
+#include "gc/parallel/psVirtualspace.hpp"
+#include "gc/shared/collectorCounters.hpp"
+#include "gc/shared/gcTrace.hpp"
+#include "memory/allocation.hpp"
+#include "oops/oop.hpp"
+#include "utilities/stack.hpp"
+
+class GCTaskManager;
+class GCTaskQueue;
+class OopStack;
+class ReferenceProcessor;
+class ParallelScavengeHeap;
+class ParallelScavengeTracer;
+class PSIsAliveClosure;
+class PSRefProcTaskExecutor;
+class STWGCTimer;
+
+class PSScavenge: AllStatic {
+ friend class PSIsAliveClosure;
+ friend class PSKeepAliveClosure;
+ friend class PSPromotionManager;
+
+ enum ScavengeSkippedCause {
+ not_skipped = 0,
+ to_space_not_empty,
+ promoted_too_large,
+ full_follows_scavenge
+ };
+
+ // Saved value of to_space->top(), used to prevent objects in to_space from
+ // being rescanned.
+ static HeapWord* _to_space_top_before_gc;
+
+ // Number of consecutive attempts to scavenge that were skipped
+ static int _consecutive_skipped_scavenges;
+
+
+ protected:
+ // Flags/counters
+ static ReferenceProcessor* _ref_processor; // Reference processor for scavenging.
+ static PSIsAliveClosure _is_alive_closure; // Closure used for reference processing
+ static CardTableExtension* _card_table; // We cache the card table for fast access.
+ static bool _survivor_overflow; // Overflow this collection
+ static uint _tenuring_threshold; // tenuring threshold for next scavenge
+ static elapsedTimer _accumulated_time; // total time spent on scavenge
+ static STWGCTimer _gc_timer; // GC time book keeper
+ static ParallelScavengeTracer _gc_tracer; // GC tracing
+ // The lowest address possible for the young_gen.
+ // This is used to decide if an oop should be scavenged,
+ // cards should be marked, etc.
+ static HeapWord* _young_generation_boundary;
+ // Used to optimize compressed oops young gen boundary checking.
+ static uintptr_t _young_generation_boundary_compressed;
+ static Stack<markOop, mtGC> _preserved_mark_stack; // List of marks to be restored after failed promotion
+ static Stack<oop, mtGC> _preserved_oop_stack; // List of oops that need their mark restored.
+ static CollectorCounters* _counters; // collector performance counters
+
+ static void clean_up_failed_promotion();
+
+ static bool should_attempt_scavenge();
+
+ static HeapWord* to_space_top_before_gc() { return _to_space_top_before_gc; }
+ static inline void save_to_space_top_before_gc();
+
+ // Private accessors
+ static CardTableExtension* const card_table() { assert(_card_table != NULL, "Sanity"); return _card_table; }
+ static const ParallelScavengeTracer* gc_tracer() { return &_gc_tracer; }
+
+ public:
+ // Accessors
+ static uint tenuring_threshold() { return _tenuring_threshold; }
+ static elapsedTimer* accumulated_time() { return &_accumulated_time; }
+ static int consecutive_skipped_scavenges()
+ { return _consecutive_skipped_scavenges; }
+
+ // Performance Counters
+ static CollectorCounters* counters() { return _counters; }
+
+ // Used by scavenge_contents && psMarkSweep
+ static ReferenceProcessor* const reference_processor() {
+ assert(_ref_processor != NULL, "Sanity");
+ return _ref_processor;
+ }
+ // Used to add tasks
+ static GCTaskManager* const gc_task_manager();
+ // The promotion managers tell us if they encountered overflow
+ static void set_survivor_overflow(bool state) {
+ _survivor_overflow = state;
+ }
+ // Adaptive size policy support. When the young generation/old generation
+ // boundary moves, _young_generation_boundary must be reset
+ static void set_young_generation_boundary(HeapWord* v) {
+ _young_generation_boundary = v;
+ if (UseCompressedOops) {
+ _young_generation_boundary_compressed = (uintptr_t)oopDesc::encode_heap_oop((oop)v);
+ }
+ }
+
+ // Called by parallelScavengeHeap to init the tenuring threshold
+ static void initialize();
+
+ // Scavenge entry point. This may invoke a full gc; return true if so.
+ static bool invoke();
+ // Return true if a collection was done; false otherwise.
+ static bool invoke_no_policy();
+
+ // If an attempt to promote fails, this method is invoked
+ static void oop_promotion_failed(oop obj, markOop obj_mark);
+
+ template <class T> static inline bool should_scavenge(T* p);
+
+ // These call should_scavenge() above and, if it returns true, also check that
+ // the object was not newly copied into to_space. The version with the bool
+ // argument is a convenience wrapper that fetches the to_space pointer from
+ // the heap and calls the other version (if the arg is true).
+ template <class T> static inline bool should_scavenge(T* p, MutableSpace* to_space);
+ template <class T> static inline bool should_scavenge(T* p, bool check_to_space);
+
+ static void copy_and_push_safe_barrier_from_klass(PSPromotionManager* pm, oop* p);
+
+ // Is an object in the young generation
+ // This assumes that the 'o' is in the heap,
+ // so it only checks one side of the complete predicate.
+
+ inline static bool is_obj_in_young(oop o) {
+ return (HeapWord*)o >= _young_generation_boundary;
+ }
+
+ inline static bool is_obj_in_young(narrowOop o) {
+ return (uintptr_t)o >= _young_generation_boundary_compressed;
+ }
+
+ inline static bool is_obj_in_young(HeapWord* o) {
+ return o >= _young_generation_boundary;
+ }
+};
+
+#endif // SHARE_VM_GC_PARALLEL_PSSCAVENGE_HPP