Mercurial > hg > graal-compiler
view src/share/vm/memory/freeList.cpp @ 9484:2b663d5893d3
Allow rounding errors in probabilities
author | Christian Wimmer <christian.wimmer@oracle.com> |
---|---|
date | Wed, 01 May 2013 13:33:07 -0700 |
parents | db9981fd3124 |
children | 7c5a1b62f53d |
line wrap: on
line source
/* * Copyright (c) 2001, 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. * */ #include "precompiled.hpp" #include "memory/freeBlockDictionary.hpp" #include "memory/freeList.hpp" #include "memory/metablock.hpp" #include "memory/metachunk.hpp" #include "memory/sharedHeap.hpp" #include "runtime/globals.hpp" #include "runtime/mutex.hpp" #include "runtime/vmThread.hpp" #include "utilities/macros.hpp" #if INCLUDE_ALL_GCS #include "gc_implementation/concurrentMarkSweep/freeChunk.hpp" #endif // INCLUDE_ALL_GCS // Free list. A FreeList is used to access a linked list of chunks // of space in the heap. The head and tail are maintained so that // items can be (as in the current implementation) added at the // at the tail of the list and removed from the head of the list to // maintain a FIFO queue. template <class Chunk> FreeList<Chunk>::FreeList() : _head(NULL), _tail(NULL) #ifdef ASSERT , _protecting_lock(NULL) #endif { _size = 0; _count = 0; } template <class Chunk> FreeList<Chunk>::FreeList(Chunk* fc) : _head(fc), _tail(fc) #ifdef ASSERT , _protecting_lock(NULL) #endif { _size = fc->size(); _count = 1; } template <class Chunk> void FreeList<Chunk>::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->link_prev(NULL); } } template <class Chunk> void FreeList<Chunk>::reset() { // Don't set the _size to 0 because this method is // used with a existing list that has a size but which has // been emptied. // Don't clear the _protecting_lock of an existing list. set_count(0); set_head(NULL); set_tail(NULL); } template <class Chunk> void FreeList<Chunk>::initialize() { #ifdef ASSERT // Needed early because it might be checked in other initializing code. set_protecting_lock(NULL); #endif reset(); set_size(0); } template <class Chunk_t> Chunk_t* FreeList<Chunk_t>::get_chunk_at_head() { assert_proper_lock_protection(); assert(head() == NULL || head()->prev() == NULL, "list invariant"); assert(tail() == NULL || tail()->next() == NULL, "list invariant"); Chunk_t* fc = head(); if (fc != NULL) { Chunk_t* nextFC = fc->next(); if (nextFC != NULL) { // The chunk fc being removed has a "next". Set the "next" to the // "prev" of fc. nextFC->link_prev(NULL); } else { // removed tail of list link_tail(NULL); } link_head(nextFC); decrement_count(); } assert(head() == NULL || head()->prev() == NULL, "list invariant"); assert(tail() == NULL || tail()->next() == NULL, "list invariant"); return fc; } template <class Chunk> void FreeList<Chunk>::getFirstNChunksFromList(size_t n, FreeList<Chunk>* fl) { assert_proper_lock_protection(); assert(fl->count() == 0, "Precondition"); if (count() > 0) { int k = 1; fl->set_head(head()); n--; Chunk* tl = head(); while (tl->next() != NULL && n > 0) { tl = tl->next(); n--; k++; } assert(tl != NULL, "Loop Inv."); // First, fix up the list we took from. Chunk* new_head = tl->next(); set_head(new_head); set_count(count() - k); if (new_head == NULL) { set_tail(NULL); } else { new_head->link_prev(NULL); } // Now we can fix up the tail. tl->link_next(NULL); // And return the result. fl->set_tail(tl); fl->set_count(k); } } // Remove this chunk from the list template <class Chunk> void FreeList<Chunk>::remove_chunk(Chunk*fc) { assert_proper_lock_protection(); assert(head() != NULL, "Remove from empty list"); assert(fc != NULL, "Remove a NULL chunk"); assert(size() == fc->size(), "Wrong list"); assert(head() == NULL || head()->prev() == NULL, "list invariant"); assert(tail() == NULL || tail()->next() == NULL, "list invariant"); Chunk* prevFC = fc->prev(); Chunk* nextFC = fc->next(); if (nextFC != NULL) { // The chunk fc being removed has a "next". Set the "next" to the // "prev" of fc. nextFC->link_prev(prevFC); } else { // removed tail of list link_tail(prevFC); } if (prevFC == NULL) { // removed head of list link_head(nextFC); assert(nextFC == NULL || nextFC->prev() == NULL, "Prev of head should be NULL"); } else { prevFC->link_next(nextFC); assert(tail() != prevFC || prevFC->next() == NULL, "Next of tail should be NULL"); } decrement_count(); assert(((head() == NULL) + (tail() == NULL) + (count() == 0)) % 3 == 0, "H/T/C Inconsistency"); // clear next and prev fields of fc, debug only NOT_PRODUCT( fc->link_prev(NULL); fc->link_next(NULL); ) assert(fc->is_free(), "Should still be a free chunk"); assert(head() == NULL || head()->prev() == NULL, "list invariant"); assert(tail() == NULL || tail()->next() == NULL, "list invariant"); assert(head() == NULL || head()->size() == size(), "wrong item on list"); assert(tail() == NULL || tail()->size() == size(), "wrong item on list"); } // Add this chunk at the head of the list. template <class Chunk> void FreeList<Chunk>::return_chunk_at_head(Chunk* chunk, bool record_return) { assert_proper_lock_protection(); assert(chunk != NULL, "insert a NULL chunk"); assert(size() == chunk->size(), "Wrong size"); assert(head() == NULL || head()->prev() == NULL, "list invariant"); assert(tail() == NULL || tail()->next() == NULL, "list invariant"); Chunk* oldHead = head(); assert(chunk != oldHead, "double insertion"); chunk->link_after(oldHead); link_head(chunk); if (oldHead == NULL) { // only chunk in list assert(tail() == NULL, "inconsistent FreeList"); link_tail(chunk); } increment_count(); // of # of chunks in list assert(head() == NULL || head()->prev() == NULL, "list invariant"); assert(tail() == NULL || tail()->next() == NULL, "list invariant"); assert(head() == NULL || head()->size() == size(), "wrong item on list"); assert(tail() == NULL || tail()->size() == size(), "wrong item on list"); } template <class Chunk> void FreeList<Chunk>::return_chunk_at_head(Chunk* chunk) { assert_proper_lock_protection(); return_chunk_at_head(chunk, true); } // Add this chunk at the tail of the list. template <class Chunk> void FreeList<Chunk>::return_chunk_at_tail(Chunk* chunk, bool record_return) { assert_proper_lock_protection(); assert(head() == NULL || head()->prev() == NULL, "list invariant"); assert(tail() == NULL || tail()->next() == NULL, "list invariant"); assert(chunk != NULL, "insert a NULL chunk"); assert(size() == chunk->size(), "wrong size"); Chunk* oldTail = tail(); assert(chunk != oldTail, "double insertion"); if (oldTail != NULL) { oldTail->link_after(chunk); } else { // only chunk in list assert(head() == NULL, "inconsistent FreeList"); link_head(chunk); } link_tail(chunk); increment_count(); // of # of chunks in list assert(head() == NULL || head()->prev() == NULL, "list invariant"); assert(tail() == NULL || tail()->next() == NULL, "list invariant"); assert(head() == NULL || head()->size() == size(), "wrong item on list"); assert(tail() == NULL || tail()->size() == size(), "wrong item on list"); } template <class Chunk> void FreeList<Chunk>::return_chunk_at_tail(Chunk* chunk) { return_chunk_at_tail(chunk, true); } template <class Chunk> void FreeList<Chunk>::prepend(FreeList<Chunk>* fl) { assert_proper_lock_protection(); if (fl->count() > 0) { if (count() == 0) { set_head(fl->head()); set_tail(fl->tail()); set_count(fl->count()); } else { // Both are non-empty. Chunk* fl_tail = fl->tail(); Chunk* this_head = head(); assert(fl_tail->next() == NULL, "Well-formedness of fl"); fl_tail->link_next(this_head); this_head->link_prev(fl_tail); set_head(fl->head()); set_count(count() + fl->count()); } fl->set_head(NULL); fl->set_tail(NULL); fl->set_count(0); } } // verify_chunk_in_free_lists() is used to verify that an item is in this free list. // It is used as a debugging aid. template <class Chunk> bool FreeList<Chunk>::verify_chunk_in_free_list(Chunk* fc) const { // This is an internal consistency check, not part of the check that the // chunk is in the free lists. guarantee(fc->size() == size(), "Wrong list is being searched"); Chunk* curFC = head(); while (curFC) { // This is an internal consistency check. guarantee(size() == curFC->size(), "Chunk is in wrong list."); if (fc == curFC) { return true; } curFC = curFC->next(); } return false; } #ifndef PRODUCT template <class Chunk> void FreeList<Chunk>::assert_proper_lock_protection_work() const { assert(protecting_lock() != NULL, "Don't call this directly"); assert(ParallelGCThreads > 0, "Don't call this directly"); Thread* thr = Thread::current(); if (thr->is_VM_thread() || thr->is_ConcurrentGC_thread()) { // assert that we are holding the freelist lock } else if (thr->is_GC_task_thread()) { assert(protecting_lock()->owned_by_self(), "FreeList RACE DETECTED"); } else if (thr->is_Java_thread()) { assert(!SafepointSynchronize::is_at_safepoint(), "Should not be executing"); } else { ShouldNotReachHere(); // unaccounted thread type? } } #endif // Print the "label line" for free list stats. template <class Chunk> void FreeList<Chunk>::print_labels_on(outputStream* st, const char* c) { st->print("%16s\t", c); st->print("%14s\t" "%14s\t" "%14s\t" "%14s\t" "%14s\t" "%14s\t" "%14s\t" "%14s\t" "%14s\t" "%14s\t" "\n", "bfrsurp", "surplus", "desired", "prvSwep", "bfrSwep", "count", "cBirths", "cDeaths", "sBirths", "sDeaths"); } // Print the AllocationStats for the given free list. If the second argument // to the call is a non-null string, it is printed in the first column; // otherwise, if the argument is null (the default), then the size of the // (free list) block is printed in the first column. template <class Chunk_t> void FreeList<Chunk_t>::print_on(outputStream* st, const char* c) const { if (c != NULL) { st->print("%16s", c); } else { st->print(SIZE_FORMAT_W(16), size()); } } template class FreeList<Metablock>; template class FreeList<Metachunk>; #if INCLUDE_ALL_GCS template class FreeList<FreeChunk>; #endif // INCLUDE_ALL_GCS