--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/memory/metaspace/chunkManager.hpp Mon May 21 11:33:59 2018 +0200
@@ -0,0 +1,229 @@
+/*
+ * Copyright (c) 2018, 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_MEMORY_METASPACE_CHUNKMANAGER_HPP
+#define SHARE_MEMORY_METASPACE_CHUNKMANAGER_HPP
+
+#include "memory/allocation.hpp"
+#include "memory/binaryTreeDictionary.hpp"
+#include "memory/freeList.inline.hpp"
+#include "memory/metaspace/metachunk.hpp"
+#include "memory/metaspace/metaspaceStatistics.hpp"
+#include "memory/metaspaceChunkFreeListSummary.hpp"
+#include "utilities/globalDefinitions.hpp"
+
+class TestVirtualSpaceNodeTest;
+
+namespace metaspace {
+
+typedef class FreeList<Metachunk> ChunkList;
+typedef BinaryTreeDictionary<Metachunk, FreeList<Metachunk> > ChunkTreeDictionary;
+
+// Manages the global free lists of chunks.
+class ChunkManager : public CHeapObj<mtInternal> {
+ friend class ::TestVirtualSpaceNodeTest;
+
+ // Free list of chunks of different sizes.
+ // SpecializedChunk
+ // SmallChunk
+ // MediumChunk
+ ChunkList _free_chunks[NumberOfFreeLists];
+
+ // Whether or not this is the class chunkmanager.
+ const bool _is_class;
+
+ // Return non-humongous chunk list by its index.
+ ChunkList* free_chunks(ChunkIndex index);
+
+ // Returns non-humongous chunk list for the given chunk word size.
+ ChunkList* find_free_chunks_list(size_t word_size);
+
+ // HumongousChunk
+ ChunkTreeDictionary _humongous_dictionary;
+
+ // Returns the humongous chunk dictionary.
+ ChunkTreeDictionary* humongous_dictionary() {
+ return &_humongous_dictionary;
+ }
+
+ // Size, in metaspace words, of all chunks managed by this ChunkManager
+ size_t _free_chunks_total;
+ // Number of chunks in this ChunkManager
+ size_t _free_chunks_count;
+
+ // Update counters after a chunk was added or removed removed.
+ void account_for_added_chunk(const Metachunk* c);
+ void account_for_removed_chunk(const Metachunk* c);
+
+ size_t sum_free_chunks();
+ size_t sum_free_chunks_count();
+
+ void locked_verify_free_chunks_total();
+ void slow_locked_verify_free_chunks_total() {
+ if (VerifyMetaspace) {
+ locked_verify_free_chunks_total();
+ }
+ }
+ void locked_verify_free_chunks_count();
+ void slow_locked_verify_free_chunks_count() {
+ if (VerifyMetaspace) {
+ locked_verify_free_chunks_count();
+ }
+ }
+
+ // Given a pointer to a chunk, attempts to merge it with neighboring
+ // free chunks to form a bigger chunk. Returns true if successful.
+ bool attempt_to_coalesce_around_chunk(Metachunk* chunk, ChunkIndex target_chunk_type);
+
+ // Helper for chunk merging:
+ // Given an address range with 1-n chunks which are all supposed to be
+ // free and hence currently managed by this ChunkManager, remove them
+ // from this ChunkManager and mark them as invalid.
+ // - This does not correct the occupancy map.
+ // - This does not adjust the counters in ChunkManager.
+ // - Does not adjust container count counter in containing VirtualSpaceNode.
+ // Returns number of chunks removed.
+ int remove_chunks_in_area(MetaWord* p, size_t word_size);
+
+ // Helper for chunk splitting: given a target chunk size and a larger free chunk,
+ // split up the larger chunk into n smaller chunks, at least one of which should be
+ // the target chunk of target chunk size. The smaller chunks, including the target
+ // chunk, are returned to the freelist. The pointer to the target chunk is returned.
+ // Note that this chunk is supposed to be removed from the freelist right away.
+ Metachunk* split_chunk(size_t target_chunk_word_size, Metachunk* chunk);
+
+ public:
+
+ ChunkManager(bool is_class)
+ : _is_class(is_class), _free_chunks_total(0), _free_chunks_count(0) {
+ _free_chunks[SpecializedIndex].set_size(get_size_for_nonhumongous_chunktype(SpecializedIndex, is_class));
+ _free_chunks[SmallIndex].set_size(get_size_for_nonhumongous_chunktype(SmallIndex, is_class));
+ _free_chunks[MediumIndex].set_size(get_size_for_nonhumongous_chunktype(MediumIndex, is_class));
+ }
+
+ // Add or delete (return) a chunk to the global freelist.
+ Metachunk* chunk_freelist_allocate(size_t word_size);
+
+ // Map a size to a list index assuming that there are lists
+ // for special, small, medium, and humongous chunks.
+ ChunkIndex list_index(size_t size);
+
+ // Map a given index to the chunk size.
+ size_t size_by_index(ChunkIndex index) const;
+
+ bool is_class() const { return _is_class; }
+
+ // Convenience accessors.
+ size_t medium_chunk_word_size() const { return size_by_index(MediumIndex); }
+ size_t small_chunk_word_size() const { return size_by_index(SmallIndex); }
+ size_t specialized_chunk_word_size() const { return size_by_index(SpecializedIndex); }
+
+ // Take a chunk from the ChunkManager. The chunk is expected to be in
+ // the chunk manager (the freelist if non-humongous, the dictionary if
+ // humongous).
+ void remove_chunk(Metachunk* chunk);
+
+ // Return a single chunk of type index to the ChunkManager.
+ void return_single_chunk(Metachunk* chunk);
+
+ // Add the simple linked list of chunks to the freelist of chunks
+ // of type index.
+ void return_chunk_list(Metachunk* chunk);
+
+ // Total of the space in the free chunks list
+ size_t free_chunks_total_words();
+ size_t free_chunks_total_bytes();
+
+ // Number of chunks in the free chunks list
+ size_t free_chunks_count();
+
+ // Remove from a list by size. Selects list based on size of chunk.
+ Metachunk* free_chunks_get(size_t chunk_word_size);
+
+#define index_bounds_check(index) \
+ assert(is_valid_chunktype(index), "Bad index: %d", (int) index)
+
+ size_t num_free_chunks(ChunkIndex index) const {
+ index_bounds_check(index);
+
+ if (index == HumongousIndex) {
+ return _humongous_dictionary.total_free_blocks();
+ }
+
+ ssize_t count = _free_chunks[index].count();
+ return count == -1 ? 0 : (size_t) count;
+ }
+
+ size_t size_free_chunks_in_bytes(ChunkIndex index) const {
+ index_bounds_check(index);
+
+ size_t word_size = 0;
+ if (index == HumongousIndex) {
+ word_size = _humongous_dictionary.total_size();
+ } else {
+ const size_t size_per_chunk_in_words = _free_chunks[index].size();
+ word_size = size_per_chunk_in_words * num_free_chunks(index);
+ }
+
+ return word_size * BytesPerWord;
+ }
+
+ MetaspaceChunkFreeListSummary chunk_free_list_summary() const {
+ return MetaspaceChunkFreeListSummary(num_free_chunks(SpecializedIndex),
+ num_free_chunks(SmallIndex),
+ num_free_chunks(MediumIndex),
+ num_free_chunks(HumongousIndex),
+ size_free_chunks_in_bytes(SpecializedIndex),
+ size_free_chunks_in_bytes(SmallIndex),
+ size_free_chunks_in_bytes(MediumIndex),
+ size_free_chunks_in_bytes(HumongousIndex));
+ }
+
+ // Debug support
+ void verify();
+ void slow_verify() {
+ if (VerifyMetaspace) {
+ verify();
+ }
+ }
+ void locked_verify();
+ void slow_locked_verify() {
+ if (VerifyMetaspace) {
+ locked_verify();
+ }
+ }
+
+ void locked_print_free_chunks(outputStream* st);
+ void locked_print_sum_free_chunks(outputStream* st);
+
+ // Fill in current statistic values to the given statistics object.
+ void collect_statistics(ChunkManagerStatistics* out) const;
+
+};
+
+} // namespace metaspace
+
+
+#endif /* SHARE_MEMORY_METASPACE_CHUNKMANAGER_HPP_ */
+