--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/memory/metaspace.hpp Sat Sep 01 13:25:18 2012 -0400
@@ -0,0 +1,249 @@
+/*
+ * Copyright (c) 2011, 2012, 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_MEMORY_METASPACE_HPP
+#define SHARE_VM_MEMORY_METASPACE_HPP
+
+#include "memory/allocation.hpp"
+#include "memory/memRegion.hpp"
+#include "runtime/virtualspace.hpp"
+#include "utilities/exceptions.hpp"
+
+// Metaspace
+//
+// Metaspaces are Arenas for the VM's metadata.
+// They are allocated one per class loader object, and one for the null
+// bootstrap class loader
+// Eventually for bootstrap loader we'll have a read-only section and read-write
+// to write for DumpSharedSpaces and read for UseSharedSpaces
+//
+// block X ---+ +-------------------+
+// | | Virtualspace |
+// | | |
+// | | |
+// | |-------------------|
+// | || Chunk |
+// | || |
+// | ||---------- |
+// +------>||| block 0 | |
+// ||---------- |
+// ||| block 1 | |
+// ||---------- |
+// || |
+// |-------------------|
+// | |
+// | |
+// +-------------------+
+//
+
+class ClassLoaderData;
+class MetaWord;
+class Mutex;
+class outputStream;
+class FreeChunk;
+template <class Chunk_t> class FreeList;
+template <class Chunk_t> class BinaryTreeDictionary;
+class SpaceManager;
+
+// Metaspaces each have a SpaceManager and allocations
+// are done by the SpaceManager. Allocations are done
+// out of the current Metachunk. When the current Metachunk
+// is exhausted, the SpaceManager gets a new one from
+// the current VirtualSpace. When the VirtualSpace is exhausted
+// the SpaceManager gets a new one. The SpaceManager
+// also manages freelists of available Chunks.
+//
+// Currently the space manager maintains the list of
+// virtual spaces and the list of chunks in use. Its
+// allocate() method returns a block for use as a
+// quantum of metadata.
+
+class VirtualSpaceList;
+
+class Metaspace : public CHeapObj<mtClass> {
+ friend class VMStructs;
+ friend class SpaceManager;
+ friend class VM_CollectForMetadataAllocation;
+ friend class MetaspaceGC;
+ friend class MetaspaceAux;
+
+ public:
+ enum MetadataType {ClassType, NonClassType};
+
+ private:
+ void initialize(Mutex* lock, size_t initial_size = 0);
+
+ static size_t _first_chunk_word_size;
+
+ SpaceManager* _vsm;
+ SpaceManager* vsm() const { return _vsm; }
+
+ SpaceManager* _class_vsm;
+ SpaceManager* class_vsm() const { return _class_vsm; }
+
+ MetaWord* allocate(size_t word_size, MetadataType mdtype);
+
+ // Virtual Space lists for both classes and other metadata
+ static VirtualSpaceList* _space_list;
+ static VirtualSpaceList* _class_space_list;
+
+ static VirtualSpaceList* space_list() { return _space_list; }
+ static VirtualSpaceList* class_space_list() { return _class_space_list; }
+
+ public:
+
+ Metaspace(Mutex* lock, size_t initial_size);
+ Metaspace(Mutex* lock);
+ ~Metaspace();
+
+ // Initialize globals for Metaspace
+ static void global_initialize();
+ static void initialize_class_space(ReservedSpace rs);
+
+ static size_t first_chunk_word_size() { return _first_chunk_word_size; }
+
+ char* bottom() const;
+ size_t used_words(MetadataType mdtype) const;
+ size_t free_words(MetadataType mdtype) const;
+ size_t capacity_words(MetadataType mdtype) const;
+ size_t waste_words(MetadataType mdtype) const;
+
+ static MetaWord* allocate(ClassLoaderData* loader_data, size_t size,
+ bool read_only, MetadataType mdtype, TRAPS);
+
+ void deallocate(MetaWord* ptr, size_t byte_size, bool is_class);
+
+#ifndef PRODUCT
+ bool contains(const void *ptr) const;
+ bool contains_class(const void *ptr) const;
+#endif
+
+ void dump(outputStream* const out) const;
+
+ void print_on(outputStream* st) const;
+ // Debugging support
+ void verify();
+};
+
+class MetaspaceAux : AllStatic {
+
+ // Statistics for class space and data space in metaspace.
+ static size_t used_in_bytes(Metaspace::MetadataType mdtype);
+ static size_t free_in_bytes(Metaspace::MetadataType mdtype);
+ static size_t capacity_in_bytes(Metaspace::MetadataType mdtype);
+ static size_t reserved_in_bytes(Metaspace::MetadataType mdtype);
+
+ static size_t free_chunks_total(Metaspace::MetadataType mdtype);
+ static size_t free_chunks_total_in_bytes(Metaspace::MetadataType mdtype);
+
+ public:
+ // Total of space allocated to metadata in all Metaspaces
+ static size_t used_in_bytes() {
+ return used_in_bytes(Metaspace::ClassType) +
+ used_in_bytes(Metaspace::NonClassType);
+ }
+
+ // Total of available space in all Metaspaces
+ // Total of capacity allocated to all Metaspaces. This includes
+ // space in Metachunks not yet allocated and in the Metachunk
+ // freelist.
+ static size_t capacity_in_bytes() {
+ return capacity_in_bytes(Metaspace::ClassType) +
+ capacity_in_bytes(Metaspace::NonClassType);
+ }
+
+ // Total space reserved in all Metaspaces
+ static size_t reserved_in_bytes() {
+ return reserved_in_bytes(Metaspace::ClassType) +
+ reserved_in_bytes(Metaspace::NonClassType);
+ }
+
+ static size_t min_chunk_size();
+
+ // Print change in used metadata.
+ static void print_metaspace_change(size_t prev_metadata_used);
+ static void print_on(outputStream * out);
+ static void print_on(outputStream * out, Metaspace::MetadataType mdtype);
+
+ static void print_waste(outputStream* out);
+ static void dump(outputStream* out);
+};
+
+// Metaspace are deallocated when their class loader are GC'ed.
+// This class implements a policy for inducing GC's to recover
+// Metaspaces.
+
+class MetaspaceGC : AllStatic {
+
+ // The current high-water-mark for inducing a GC. When
+ // the capacity of all space in the virtual lists reaches this value,
+ // a GC is induced and the value is increased. This should be changed
+ // to the space actually used for allocations to avoid affects of
+ // fragmentation losses to partially used chunks. Size is in words.
+ static size_t _capacity_until_GC;
+
+ // After a GC is done any allocation that fails should try to expand
+ // the capacity of the Metaspaces. This flag is set during attempts
+ // to allocate in the VMGCOperation that does the GC.
+ static bool _expand_after_GC;
+
+ // For a CMS collection, signal that a concurrent collection should
+ // be started.
+ static bool _should_concurrent_collect;
+
+ static uint _shrink_factor;
+
+ static void set_capacity_until_GC(size_t v) { _capacity_until_GC = v; }
+
+ static size_t shrink_factor() { return _shrink_factor; }
+ void set_shrink_factor(uint v) { _shrink_factor = v; }
+
+ public:
+
+ static size_t capacity_until_GC() { return _capacity_until_GC; }
+ static size_t capacity_until_GC_in_bytes() { return _capacity_until_GC * BytesPerWord; }
+ static void inc_capacity_until_GC(size_t v) { _capacity_until_GC += v; }
+ static void dec_capacity_until_GC(size_t v) {
+ _capacity_until_GC = _capacity_until_GC > v ? _capacity_until_GC - v : 0;
+ }
+ static bool expand_after_GC() { return _expand_after_GC; }
+ static void set_expand_after_GC(bool v) { _expand_after_GC = v; }
+
+ static bool should_concurrent_collect() { return _should_concurrent_collect; }
+ static void set_should_concurrent_collect(bool v) {
+ _should_concurrent_collect = v;
+ }
+
+ // The amount to increase the high-water-mark (_capacity_until_GC)
+ static size_t delta_capacity_until_GC(size_t word_size);
+
+ // It is expected that this will be called when the current capacity
+ // has been used and a GC should be considered.
+ static bool should_expand(VirtualSpaceList* vsl, size_t word_size);
+
+ // Calculate the new high-water mark at which to induce
+ // a GC.
+ static void compute_new_size();
+};
+
+#endif // SHARE_VM_MEMORY_METASPACE_HPP