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src/hotspot/share/memory/metaspace/chunkManager.hpp
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rev 60538 : imported patch jep387-all.patch
*** 1,7 ****
/*
! * Copyright (c) 2018, 2019, 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.
--- 1,8 ----
/*
! * Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
! * Copyright (c) 2018, 2020 SAP SE. 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.
*** 24,198 ****
#ifndef SHARE_MEMORY_METASPACE_CHUNKMANAGER_HPP
#define SHARE_MEMORY_METASPACE_CHUNKMANAGER_HPP
#include "memory/allocation.hpp"
! #include "memory/binaryTreeDictionary.hpp"
! #include "memory/freeList.hpp"
#include "memory/metaspace/metachunk.hpp"
- #include "memory/metaspace/metaspaceStatistics.hpp"
- #include "memory/metaspaceChunkFreeListSummary.hpp"
- #include "utilities/globalDefinitions.hpp"
-
- class ChunkManagerTestAccessor;
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 ::ChunkManagerTestAccessor;
!
! // 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; }
! const ChunkTreeDictionary* humongous_dictionary() const { 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);
!
! // 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);
!
! // 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() const { return _free_chunks_total; }
! size_t free_chunks_total_bytes() const { return free_chunks_total_words() * BytesPerWord; }
!
! // Number of chunks in the free chunks list
! size_t free_chunks_count() const { return _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));
! }
!
! #ifdef ASSERT
! // Debug support
! // Verify free list integrity. slow=true: verify chunk-internal integrity too.
! void verify(bool slow) const;
! void locked_verify(bool slow) const;
! #endif
! void locked_print_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
--- 25,192 ----
#ifndef SHARE_MEMORY_METASPACE_CHUNKMANAGER_HPP
#define SHARE_MEMORY_METASPACE_CHUNKMANAGER_HPP
#include "memory/allocation.hpp"
! #include "memory/metaspace/chunkLevel.hpp"
! #include "memory/metaspace/counter.hpp"
! #include "memory/metaspace/freeChunkList.hpp"
#include "memory/metaspace/metachunk.hpp"
namespace metaspace {
! class VirtualSpaceList;
! struct cm_stats_t;
! // ChunkManager has a somewhat central role.
! // Arenas request chunks from it and, on death, return chunks back to it.
! // It keeps freelists for chunks, one per chunk level, sorted by chunk
! // commit state.
! // To feed the freelists, it allocates root chunks from the associated
! // VirtualSpace below it.
! //
! // ChunkManager directs splitting chunks, if a chunk request cannot be
! // fulfilled directly. It also takes care of merging when chunks are
! // returned to it, before they are added to the freelist.
! //
! // The freelists are double linked double headed; fully committed chunks
! // are added to the front, others to the back.
! //
! // Level
! // +--------------------+ +--------------------+
! // 0 +----| free root chunk |---| free root chunk |---...
! // | +--------------------+ +--------------------+
! // |
! // | +----------+ +----------+
! // 1 +----| |---| |---...
! // | +----------+ +----------+
! // |
! // .
! // .
! // .
! //
! // | +-+ +-+
! // 12 +----| |---| |---...
! // +-+ +-+
!
!
! class ChunkManager : public CHeapObj<mtMetaspace> {
!
! // A chunk manager is connected to a virtual space list which is used
! // to allocate new root chunks when no free chunks are found.
! VirtualSpaceList* const _vslist;
!
! // Name
! const char* const _name;
!
! // Freelists
! FreeChunkListVector _chunks;
!
! // Returns true if this manager contains the given chunk. Slow (walks free lists) and
! // only needed for verifications.
! DEBUG_ONLY(bool contains_chunk(Metachunk* c) const;)
!
! // Given a chunk, split it into a target chunk of a smaller size (target level)
! // at least one, possible more splinter chunks. Splinter chunks are added to the
! // freelist.
! // The original chunk must be outside of the freelist and its state must be free.
! // The resulting target chunk will be located at the same address as the original
! // chunk, but it will of course be smaller (of a higher level).
! // The committed areas within the original chunk carry over to the resulting
! // chunks.
! void split_chunk_and_add_splinters(Metachunk* c, chunklevel_t target_level);
!
! // See get_chunk(s,s,s)
! Metachunk* get_chunk_locked(size_t preferred_word_size, size_t min_word_size, size_t min_committed_words);
!
! // Uncommit all chunks equal or below the given level.
! void uncommit_free_chunks(chunklevel_t max_level);
!
! // Return a single chunk to the freelist without doing any merging, and adjust accounting.
! void return_chunk_simple_locked(Metachunk* c);
!
! // See return_chunk().
! void return_chunk_locked(Metachunk* c);
!
! public:
!
! // Creates a chunk manager with a given name (which is for debug purposes only)
! // and an associated space list which will be used to request new chunks from
! // (see get_chunk())
! ChunkManager(const char* name, VirtualSpaceList* space_list);
!
! // On success, returns a chunk of level of <preferred_level>, but at most <max_level>.
! // The first first <min_committed_words> of the chunk are guaranteed to be committed.
! // On error, will return NULL.
! //
! // This function may fail for two reasons:
! // - Either we are unable to reserve space for a new chunk (if the underlying VirtualSpaceList
! // is non-expandable but needs expanding - aka out of compressed class space).
! // - Or, if the necessary space cannot be committed because we hit a commit limit.
! // This may be either the GC threshold or MaxMetaspaceSize.
! Metachunk* get_chunk(chunklevel_t preferred_level, chunklevel_t max_level, size_t min_committed_words);
!
! // Convenience function - get a chunk of a given level, uncommitted.
! Metachunk* get_chunk(chunklevel_t lvl) { return get_chunk(lvl, lvl, 0); }
!
! // Return a single chunk to the ChunkManager and adjust accounting. May merge chunk
! // with neighbors.
! // Happens after a Classloader was unloaded and releases its metaspace chunks.
! // !! Notes:
! // 1) After this method returns, c may not be valid anymore. ** Do not access c after this function returns **.
! // 2) This function will not remove c from its current chunk list. This has to be done by the caller prior to
! // calling this method.
! void return_chunk(Metachunk* c);
!
! // Given a chunk c, which must be "in use" and must not be a root chunk, attempt to
! // enlarge it in place by claiming its trailing buddy.
! //
! // This will only work if c is the leader of the buddy pair and the trailing buddy is free.
! //
! // If successful, the follower chunk will be removed from the freelists, the leader chunk c will
! // double in size (level decreased by one).
! //
! // On success, true is returned, false otherwise.
! bool attempt_enlarge_chunk(Metachunk* c);
!
! // Attempt to reclaim free areas in metaspace wholesale:
! // - first, attempt to purge nodes of the backing virtual space list: nodes which are completely
! // unused get unmapped and deleted completely.
! // - second, it will uncommit free chunks depending on commit granule size.
! void purge();
!
! // Run verifications. slow=true: verify chunk-internal integrity too.
! DEBUG_ONLY(void verify(bool slow) const;)
! DEBUG_ONLY(void verify_locked(bool slow) const;)
!
! // Returns the name of this chunk manager.
! const char* name() const { return _name; }
!
! // Returns total number of chunks
! int total_num_chunks() const { return _chunks.num_chunks(); }
!
! // Returns number of words in all free chunks (regardless of commit state).
! size_t total_word_size() const { return _chunks.word_size(); }
!
! // Returns number of committed words in all free chunks.
! size_t total_committed_word_size() const { return _chunks.committed_word_size(); }
!
! // Update statistics.
! void add_to_statistics(cm_stats_t* out) const;
!
! void print_on(outputStream* st) const;
! void print_on_locked(outputStream* st) const;
!
! public:
!
! // Convenience methods to return the global class-space chunkmanager
! // and non-class chunkmanager, respectively.
! static ChunkManager* chunkmanager_class();
! static ChunkManager* chunkmanager_nonclass();
};
} // namespace metaspace
#endif // SHARE_MEMORY_METASPACE_CHUNKMANAGER_HPP
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