Mercurial > hg > truffle
diff src/share/vm/memory/freeList.hpp @ 6026:9f059abe8cf2
7131629: Generalize the CMS free list code
Summary: Make the FreeChunk, FreeList, TreeList, and BinaryTreeDictionary classes usable outside CMS.
Reviewed-by: brutisso, johnc, jwilhelm
Contributed-by: coleen.phillimore@oracle.com
author | jmasa |
---|---|
date | Thu, 29 Mar 2012 19:46:24 -0700 |
parents | src/share/vm/gc_implementation/concurrentMarkSweep/freeList.hpp@f95d63e2154a |
children | f69a5d43dc19 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/memory/freeList.hpp Thu Mar 29 19:46:24 2012 -0700 @@ -0,0 +1,329 @@ +/* + * Copyright (c) 2001, 2010, 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_FREELIST_HPP +#define SHARE_VM_MEMORY_FREELIST_HPP + +#include "gc_implementation/shared/allocationStats.hpp" + +class CompactibleFreeListSpace; + +// A class for maintaining a free list of Chunk's. The FreeList +// maintains a the structure of the list (head, tail, etc.) plus +// statistics for allocations from the list. The links between items +// are not part of FreeList. The statistics are +// used to make decisions about coalescing Chunk's when they +// are swept during collection. +// +// See the corresponding .cpp file for a description of the specifics +// for that implementation. + +class Mutex; +template <class Chunk> class TreeList; +template <class Chunk> class PrintTreeCensusClosure; + +template <class Chunk> +class FreeList VALUE_OBJ_CLASS_SPEC { + friend class CompactibleFreeListSpace; + friend class VMStructs; + friend class PrintTreeCensusClosure<Chunk>; + + private: + Chunk* _head; // Head of list of free chunks + Chunk* _tail; // Tail of list of free chunks + size_t _size; // Size in Heap words of each chunk + ssize_t _count; // Number of entries in list + size_t _hint; // next larger size list with a positive surplus + + AllocationStats _allocation_stats; // allocation-related statistics + +#ifdef ASSERT + Mutex* _protecting_lock; +#endif + + // Asserts false if the protecting lock (if any) is not held. + void assert_proper_lock_protection_work() const PRODUCT_RETURN; + void assert_proper_lock_protection() const { +#ifdef ASSERT + if (_protecting_lock != NULL) + assert_proper_lock_protection_work(); +#endif + } + + // Initialize the allocation statistics. + protected: + void init_statistics(bool split_birth = false); + void set_count(ssize_t v) { _count = v;} + void increment_count() { + _count++; + } + + void decrement_count() { + _count--; + assert(_count >= 0, "Count should not be negative"); + } + + public: + // Constructor + // Construct a list without any entries. + FreeList(); + // Construct a list with "fc" as the first (and lone) entry in the list. + FreeList(Chunk* fc); + + // Reset the head, tail, hint, and count of a free list. + void reset(size_t hint); + + // Declare the current free list to be protected by the given lock. +#ifdef ASSERT + void set_protecting_lock(Mutex* protecting_lock) { + _protecting_lock = protecting_lock; + } +#endif + + // Accessors. + Chunk* head() const { + assert_proper_lock_protection(); + return _head; + } + void set_head(Chunk* v) { + assert_proper_lock_protection(); + _head = v; + assert(!_head || _head->size() == _size, "bad chunk size"); + } + // Set the head of the list and set the prev field of non-null + // values to NULL. + void link_head(Chunk* v) { + assert_proper_lock_protection(); + set_head(v); + // If this method is not used (just set the head instead), + // this check can be avoided. + if (v != NULL) { + v->linkPrev(NULL); + } + } + + Chunk* tail() const { + assert_proper_lock_protection(); + return _tail; + } + void set_tail(Chunk* v) { + assert_proper_lock_protection(); + _tail = v; + assert(!_tail || _tail->size() == _size, "bad chunk size"); + } + // Set the tail of the list and set the next field of non-null + // values to NULL. + void link_tail(Chunk* v) { + assert_proper_lock_protection(); + set_tail(v); + if (v != NULL) { + v->clearNext(); + } + } + + // No locking checks in read-accessors: lock-free reads (only) are benign. + // Readers are expected to have the lock if they are doing work that + // requires atomicity guarantees in sections of code. + size_t size() const { + return _size; + } + void set_size(size_t v) { + assert_proper_lock_protection(); + _size = v; + } + ssize_t count() const { + return _count; + } + size_t hint() const { + return _hint; + } + void set_hint(size_t v) { + assert_proper_lock_protection(); + assert(v == 0 || _size < v, "Bad hint"); _hint = v; + } + + // Accessors for statistics + AllocationStats* allocation_stats() { + assert_proper_lock_protection(); + return &_allocation_stats; + } + + ssize_t desired() const { + return _allocation_stats.desired(); + } + void set_desired(ssize_t v) { + assert_proper_lock_protection(); + _allocation_stats.set_desired(v); + } + void compute_desired(float inter_sweep_current, + float inter_sweep_estimate, + float intra_sweep_estimate) { + assert_proper_lock_protection(); + _allocation_stats.compute_desired(_count, + inter_sweep_current, + inter_sweep_estimate, + intra_sweep_estimate); + } + ssize_t coalDesired() const { + return _allocation_stats.coalDesired(); + } + void set_coalDesired(ssize_t v) { + assert_proper_lock_protection(); + _allocation_stats.set_coalDesired(v); + } + + ssize_t surplus() const { + return _allocation_stats.surplus(); + } + void set_surplus(ssize_t v) { + assert_proper_lock_protection(); + _allocation_stats.set_surplus(v); + } + void increment_surplus() { + assert_proper_lock_protection(); + _allocation_stats.increment_surplus(); + } + void decrement_surplus() { + assert_proper_lock_protection(); + _allocation_stats.decrement_surplus(); + } + + ssize_t bfrSurp() const { + return _allocation_stats.bfrSurp(); + } + void set_bfrSurp(ssize_t v) { + assert_proper_lock_protection(); + _allocation_stats.set_bfrSurp(v); + } + ssize_t prevSweep() const { + return _allocation_stats.prevSweep(); + } + void set_prevSweep(ssize_t v) { + assert_proper_lock_protection(); + _allocation_stats.set_prevSweep(v); + } + ssize_t beforeSweep() const { + return _allocation_stats.beforeSweep(); + } + void set_beforeSweep(ssize_t v) { + assert_proper_lock_protection(); + _allocation_stats.set_beforeSweep(v); + } + + ssize_t coalBirths() const { + return _allocation_stats.coalBirths(); + } + void set_coalBirths(ssize_t v) { + assert_proper_lock_protection(); + _allocation_stats.set_coalBirths(v); + } + void increment_coalBirths() { + assert_proper_lock_protection(); + _allocation_stats.increment_coalBirths(); + } + + ssize_t coalDeaths() const { + return _allocation_stats.coalDeaths(); + } + void set_coalDeaths(ssize_t v) { + assert_proper_lock_protection(); + _allocation_stats.set_coalDeaths(v); + } + void increment_coalDeaths() { + assert_proper_lock_protection(); + _allocation_stats.increment_coalDeaths(); + } + + ssize_t splitBirths() const { + return _allocation_stats.splitBirths(); + } + void set_splitBirths(ssize_t v) { + assert_proper_lock_protection(); + _allocation_stats.set_splitBirths(v); + } + void increment_splitBirths() { + assert_proper_lock_protection(); + _allocation_stats.increment_splitBirths(); + } + + ssize_t splitDeaths() const { + return _allocation_stats.splitDeaths(); + } + void set_splitDeaths(ssize_t v) { + assert_proper_lock_protection(); + _allocation_stats.set_splitDeaths(v); + } + void increment_splitDeaths() { + assert_proper_lock_protection(); + _allocation_stats.increment_splitDeaths(); + } + + NOT_PRODUCT( + // For debugging. The "_returnedBytes" in all the lists are summed + // and compared with the total number of bytes swept during a + // collection. + size_t returnedBytes() const { return _allocation_stats.returnedBytes(); } + void set_returnedBytes(size_t v) { _allocation_stats.set_returnedBytes(v); } + void increment_returnedBytes_by(size_t v) { + _allocation_stats.set_returnedBytes(_allocation_stats.returnedBytes() + v); + } + ) + + // Unlink head of list and return it. Returns NULL if + // the list is empty. + Chunk* getChunkAtHead(); + + // Remove the first "n" or "count", whichever is smaller, chunks from the + // list, setting "fl", which is required to be empty, to point to them. + void getFirstNChunksFromList(size_t n, FreeList<Chunk>* fl); + + // Unlink this chunk from it's free list + void removeChunk(Chunk* fc); + + // Add this chunk to this free list. + void returnChunkAtHead(Chunk* fc); + void returnChunkAtTail(Chunk* fc); + + // Similar to returnChunk* but also records some diagnostic + // information. + void returnChunkAtHead(Chunk* fc, bool record_return); + void returnChunkAtTail(Chunk* fc, bool record_return); + + // Prepend "fl" (whose size is required to be the same as that of "this") + // to the front of "this" list. + void prepend(FreeList<Chunk>* fl); + + // Verify that the chunk is in the list. + // found. Return NULL if "fc" is not found. + bool verifyChunkInFreeLists(Chunk* fc) const; + + // Stats verification + void verify_stats() const PRODUCT_RETURN; + + // Printing support + static void print_labels_on(outputStream* st, const char* c); + void print_on(outputStream* st, const char* c = NULL) const; +}; + +#endif // SHARE_VM_MEMORY_FREELIST_HPP