--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/freeList.cpp	Wed May 09 13:08:07 2012 -0700
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,360 +0,0 @@
-/*
- * 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.
- *
- */
-
-#include "precompiled.hpp"
-#include "gc_implementation/concurrentMarkSweep/freeBlockDictionary.hpp"
-#include "gc_implementation/concurrentMarkSweep/freeList.hpp"
-#include "memory/sharedHeap.hpp"
-#include "runtime/globals.hpp"
-#include "runtime/mutex.hpp"
-#include "runtime/vmThread.hpp"
-
-// 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.
-
-FreeList::FreeList() :
-  _head(NULL), _tail(NULL)
-#ifdef ASSERT
-  , _protecting_lock(NULL)
-#endif
-{
-  _size         = 0;
-  _count        = 0;
-  _hint         = 0;
-  init_statistics();
-}
-
-FreeList::FreeList(FreeChunk* fc) :
-  _head(fc), _tail(fc)
-#ifdef ASSERT
-  , _protecting_lock(NULL)
-#endif
-{
-  _size         = fc->size();
-  _count        = 1;
-  _hint         = 0;
-  init_statistics();
-#ifndef PRODUCT
-  _allocation_stats.set_returnedBytes(size() * HeapWordSize);
-#endif
-}
-
-FreeList::FreeList(HeapWord* addr, size_t size) :
-  _head((FreeChunk*) addr), _tail((FreeChunk*) addr)
-#ifdef ASSERT
-  , _protecting_lock(NULL)
-#endif
-{
-  assert(size > sizeof(FreeChunk), "size is too small");
-  head()->setSize(size);
-  _size         = size;
-  _count        = 1;
-  init_statistics();
-#ifndef PRODUCT
-  _allocation_stats.set_returnedBytes(_size * HeapWordSize);
-#endif
-}
-
-void FreeList::reset(size_t hint) {
-  set_count(0);
-  set_head(NULL);
-  set_tail(NULL);
-  set_hint(hint);
-}
-
-void FreeList::init_statistics(bool split_birth) {
-  _allocation_stats.initialize(split_birth);
-}
-
-FreeChunk* FreeList::getChunkAtHead() {
-  assert_proper_lock_protection();
-  assert(head() == NULL || head()->prev() == NULL, "list invariant");
-  assert(tail() == NULL || tail()->next() == NULL, "list invariant");
-  FreeChunk* fc = head();
-  if (fc != NULL) {
-    FreeChunk* nextFC = fc->next();
-    if (nextFC != NULL) {
-      // The chunk fc being removed has a "next".  Set the "next" to the
-      // "prev" of fc.
-      nextFC->linkPrev(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;
-}
-
-
-void FreeList::getFirstNChunksFromList(size_t n, FreeList* fl) {
-  assert_proper_lock_protection();
-  assert(fl->count() == 0, "Precondition");
-  if (count() > 0) {
-    int k = 1;
-    fl->set_head(head()); n--;
-    FreeChunk* 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.
-    FreeChunk* new_head = tl->next();
-    set_head(new_head);
-    set_count(count() - k);
-    if (new_head == NULL) {
-      set_tail(NULL);
-    } else {
-      new_head->linkPrev(NULL);
-    }
-    // Now we can fix up the tail.
-    tl->linkNext(NULL);
-    // And return the result.
-    fl->set_tail(tl);
-    fl->set_count(k);
-  }
-}
-
-// Remove this chunk from the list
-void FreeList::removeChunk(FreeChunk*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");
-
-   FreeChunk* prevFC = fc->prev();
-   FreeChunk* nextFC = fc->next();
-   if (nextFC != NULL) {
-     // The chunk fc being removed has a "next".  Set the "next" to the
-     // "prev" of fc.
-     nextFC->linkPrev(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->linkNext(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->linkPrev(NULL);
-     fc->linkNext(NULL);
-   )
-   assert(fc->isFree(), "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.
-void FreeList::returnChunkAtHead(FreeChunk* 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");
-
-  FreeChunk* oldHead = head();
-  assert(chunk != oldHead, "double insertion");
-  chunk->linkAfter(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
-  DEBUG_ONLY(
-    if (record_return) {
-      increment_returnedBytes_by(size()*HeapWordSize);
-    }
-  )
-  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");
-}
-
-void FreeList::returnChunkAtHead(FreeChunk* chunk) {
-  assert_proper_lock_protection();
-  returnChunkAtHead(chunk, true);
-}
-
-// Add this chunk at the tail of the list.
-void FreeList::returnChunkAtTail(FreeChunk* 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");
-
-  FreeChunk* oldTail = tail();
-  assert(chunk != oldTail, "double insertion");
-  if (oldTail != NULL) {
-    oldTail->linkAfter(chunk);
-  } else { // only chunk in list
-    assert(head() == NULL, "inconsistent FreeList");
-    link_head(chunk);
-  }
-  link_tail(chunk);
-  increment_count();  // of # of chunks in list
-  DEBUG_ONLY(
-    if (record_return) {
-      increment_returnedBytes_by(size()*HeapWordSize);
-    }
-  )
-  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");
-}
-
-void FreeList::returnChunkAtTail(FreeChunk* chunk) {
-  returnChunkAtTail(chunk, true);
-}
-
-void FreeList::prepend(FreeList* 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.
-      FreeChunk* fl_tail = fl->tail();
-      FreeChunk* this_head = head();
-      assert(fl_tail->next() == NULL, "Well-formedness of fl");
-      fl_tail->linkNext(this_head);
-      this_head->linkPrev(fl_tail);
-      set_head(fl->head());
-      set_count(count() + fl->count());
-    }
-    fl->set_head(NULL);
-    fl->set_tail(NULL);
-    fl->set_count(0);
-  }
-}
-
-// verifyChunkInFreeLists() is used to verify that an item is in this free list.
-// It is used as a debugging aid.
-bool FreeList::verifyChunkInFreeLists(FreeChunk* 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");
-  FreeChunk* 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
-void FreeList::verify_stats() const {
-  // The +1 of the LH comparand is to allow some "looseness" in
-  // checking: we usually call this interface when adding a block
-  // and we'll subsequently update the stats; we cannot update the
-  // stats beforehand because in the case of the large-block BT
-  // dictionary for example, this might be the first block and
-  // in that case there would be no place that we could record
-  // the stats (which are kept in the block itself).
-  assert((_allocation_stats.prevSweep() + _allocation_stats.splitBirths()
-          + _allocation_stats.coalBirths() + 1)   // Total Production Stock + 1
-         >= (_allocation_stats.splitDeaths() + _allocation_stats.coalDeaths()
-             + (ssize_t)count()),                // Total Current Stock + depletion
-         err_msg("FreeList " PTR_FORMAT " of size " SIZE_FORMAT
-                 " violates Conservation Principle: "
-                 "prevSweep(" SIZE_FORMAT ")"
-                 " + splitBirths(" SIZE_FORMAT ")"
-                 " + coalBirths(" SIZE_FORMAT ") + 1 >= "
-                 " splitDeaths(" SIZE_FORMAT ")"
-                 " coalDeaths(" SIZE_FORMAT ")"
-                 " + count(" SSIZE_FORMAT ")",
-                 this, _size, _allocation_stats.prevSweep(), _allocation_stats.splitBirths(),
-                 _allocation_stats.splitBirths(), _allocation_stats.splitDeaths(),
-                 _allocation_stats.coalDeaths(), count()));
-}
-
-void FreeList::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.
-void FreeList::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.
-void FreeList::print_on(outputStream* st, const char* c) const {
-  if (c != NULL) {
-    st->print("%16s", c);
-  } else {
-    st->print(SIZE_FORMAT_W(16), size());
-  }
-  st->print("\t"
-           SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t"
-           SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\t" SSIZE_FORMAT_W(14) "\n",
-           bfrSurp(),             surplus(),             desired(),             prevSweep(),           beforeSweep(),
-           count(),               coalBirths(),          coalDeaths(),          splitBirths(),         splitDeaths());
-}