--- old/src/share/vm/gc/g1/ptrQueue.cpp	2016-04-15 21:13:42.647234531 +0200
+++ /dev/null	2016-04-06 16:50:13.857579065 +0200
@@ -1,339 +0,0 @@
-/*
- * Copyright (c) 2001, 2016, 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/g1/ptrQueue.hpp"
-#include "memory/allocation.hpp"
-#include "memory/allocation.inline.hpp"
-#include "runtime/mutex.hpp"
-#include "runtime/mutexLocker.hpp"
-#include "runtime/thread.inline.hpp"
-
-#include <new>
-
-PtrQueue::PtrQueue(PtrQueueSet* qset, bool permanent, bool active) :
-  _qset(qset), _buf(NULL), _index(0), _sz(0), _active(active),
-  _permanent(permanent), _lock(NULL)
-{}
-
-PtrQueue::~PtrQueue() {
-  assert(_permanent || (_buf == NULL), "queue must be flushed before delete");
-}
-
-void PtrQueue::flush_impl() {
-  if (!_permanent && _buf != NULL) {
-    BufferNode* node = BufferNode::make_node_from_buffer(_buf, _index);
-    if (is_empty()) {
-      // No work to do.
-      qset()->deallocate_buffer(node);
-    } else {
-      qset()->enqueue_complete_buffer(node);
-    }
-    _buf = NULL;
-    _index = 0;
-  }
-}
-
-
-void PtrQueue::enqueue_known_active(void* ptr) {
-  assert(_index <= _sz, "Invariant.");
-  assert(_index == 0 || _buf != NULL, "invariant");
-
-  while (_index == 0) {
-    handle_zero_index();
-  }
-
-  assert(_index > 0, "postcondition");
-  _index -= sizeof(void*);
-  _buf[byte_index_to_index(_index)] = ptr;
-  assert(_index <= _sz, "Invariant.");
-}
-
-void PtrQueue::locking_enqueue_completed_buffer(BufferNode* node) {
-  assert(_lock->owned_by_self(), "Required.");
-
-  // We have to unlock _lock (which may be Shared_DirtyCardQ_lock) before
-  // we acquire DirtyCardQ_CBL_mon inside enqueue_complete_buffer as they
-  // have the same rank and we may get the "possible deadlock" message
-  _lock->unlock();
-
-  qset()->enqueue_complete_buffer(node);
-  // We must relock only because the caller will unlock, for the normal
-  // case.
-  _lock->lock_without_safepoint_check();
-}
-
-
-BufferNode* BufferNode::allocate(size_t byte_size) {
-  assert(byte_size > 0, "precondition");
-  assert(is_size_aligned(byte_size, sizeof(void**)),
-         "Invalid buffer size " SIZE_FORMAT, byte_size);
-  void* data = NEW_C_HEAP_ARRAY(char, buffer_offset() + byte_size, mtGC);
-  return new (data) BufferNode;
-}
-
-void BufferNode::deallocate(BufferNode* node) {
-  node->~BufferNode();
-  FREE_C_HEAP_ARRAY(char, node);
-}
-
-PtrQueueSet::PtrQueueSet(bool notify_when_complete) :
-  _max_completed_queue(0),
-  _cbl_mon(NULL), _fl_lock(NULL),
-  _notify_when_complete(notify_when_complete),
-  _sz(0),
-  _completed_buffers_head(NULL),
-  _completed_buffers_tail(NULL),
-  _n_completed_buffers(0),
-  _process_completed_threshold(0), _process_completed(false),
-  _buf_free_list(NULL), _buf_free_list_sz(0)
-{
-  _fl_owner = this;
-}
-
-PtrQueueSet::~PtrQueueSet() {
-  // There are presently only a couple (derived) instances ever
-  // created, and they are permanent, so no harm currently done by
-  // doing nothing here.
-}
-
-void PtrQueueSet::initialize(Monitor* cbl_mon,
-                             Mutex* fl_lock,
-                             int process_completed_threshold,
-                             int max_completed_queue,
-                             PtrQueueSet *fl_owner) {
-  _max_completed_queue = max_completed_queue;
-  _process_completed_threshold = process_completed_threshold;
-  _completed_queue_padding = 0;
-  assert(cbl_mon != NULL && fl_lock != NULL, "Init order issue?");
-  _cbl_mon = cbl_mon;
-  _fl_lock = fl_lock;
-  _fl_owner = (fl_owner != NULL) ? fl_owner : this;
-}
-
-void** PtrQueueSet::allocate_buffer() {
-  assert(_sz > 0, "Didn't set a buffer size.");
-  BufferNode* node = NULL;
-  {
-    MutexLockerEx x(_fl_owner->_fl_lock, Mutex::_no_safepoint_check_flag);
-    node = _fl_owner->_buf_free_list;
-    if (node != NULL) {
-      _fl_owner->_buf_free_list = node->next();
-      _fl_owner->_buf_free_list_sz--;
-    }
-  }
-  if (node == NULL) {
-    node = BufferNode::allocate(_sz);
-  } else {
-    // Reinitialize buffer obtained from free list.
-    node->set_index(0);
-    node->set_next(NULL);
-  }
-  return BufferNode::make_buffer_from_node(node);
-}
-
-void PtrQueueSet::deallocate_buffer(BufferNode* node) {
-  assert(_sz > 0, "Didn't set a buffer size.");
-  MutexLockerEx x(_fl_owner->_fl_lock, Mutex::_no_safepoint_check_flag);
-  node->set_next(_fl_owner->_buf_free_list);
-  _fl_owner->_buf_free_list = node;
-  _fl_owner->_buf_free_list_sz++;
-}
-
-void PtrQueueSet::reduce_free_list() {
-  assert(_fl_owner == this, "Free list reduction is allowed only for the owner");
-  // For now we'll adopt the strategy of deleting half.
-  MutexLockerEx x(_fl_lock, Mutex::_no_safepoint_check_flag);
-  size_t n = _buf_free_list_sz / 2;
-  for (size_t i = 0; i < n; ++i) {
-    assert(_buf_free_list != NULL,
-           "_buf_free_list_sz is wrong: " SIZE_FORMAT, _buf_free_list_sz);
-    BufferNode* node = _buf_free_list;
-    _buf_free_list = node->next();
-    _buf_free_list_sz--;
-    BufferNode::deallocate(node);
-  }
-}
-
-void PtrQueue::handle_zero_index() {
-  assert(_index == 0, "Precondition.");
-
-  // This thread records the full buffer and allocates a new one (while
-  // holding the lock if there is one).
-  if (_buf != NULL) {
-    if (!should_enqueue_buffer()) {
-      assert(_index > 0, "the buffer can only be re-used if it's not full");
-      return;
-    }
-
-    if (_lock) {
-      assert(_lock->owned_by_self(), "Required.");
-
-      // The current PtrQ may be the shared dirty card queue and
-      // may be being manipulated by more than one worker thread
-      // during a pause. Since the enqueueing of the completed
-      // buffer unlocks the Shared_DirtyCardQ_lock more than one
-      // worker thread can 'race' on reading the shared queue attributes
-      // (_buf and _index) and multiple threads can call into this
-      // routine for the same buffer. This will cause the completed
-      // buffer to be added to the CBL multiple times.
-
-      // We "claim" the current buffer by caching value of _buf in
-      // a local and clearing the field while holding _lock. When
-      // _lock is released (while enqueueing the completed buffer)
-      // the thread that acquires _lock will skip this code,
-      // preventing the subsequent the multiple enqueue, and
-      // install a newly allocated buffer below.
-
-      BufferNode* node = BufferNode::make_node_from_buffer(_buf, _index);
-      _buf = NULL;         // clear shared _buf field
-
-      locking_enqueue_completed_buffer(node); // enqueue completed buffer
-
-      // While the current thread was enqueueing the buffer another thread
-      // may have a allocated a new buffer and inserted it into this pointer
-      // queue. If that happens then we just return so that the current
-      // thread doesn't overwrite the buffer allocated by the other thread
-      // and potentially losing some dirtied cards.
-
-      if (_buf != NULL) return;
-    } else {
-      BufferNode* node = BufferNode::make_node_from_buffer(_buf, _index);
-      if (qset()->process_or_enqueue_complete_buffer(node)) {
-        // Recycle the buffer. No allocation.
-        assert(_buf == BufferNode::make_buffer_from_node(node), "invariant");
-        assert(_sz == qset()->buffer_size(), "invariant");
-        _index = _sz;
-        return;
-      }
-    }
-  }
-  // Reallocate the buffer
-  _buf = qset()->allocate_buffer();
-  _sz = qset()->buffer_size();
-  _index = _sz;
-}
-
-bool PtrQueueSet::process_or_enqueue_complete_buffer(BufferNode* node) {
-  if (Thread::current()->is_Java_thread()) {
-    // We don't lock. It is fine to be epsilon-precise here.
-    if (_max_completed_queue == 0 || _max_completed_queue > 0 &&
-        _n_completed_buffers >= _max_completed_queue + _completed_queue_padding) {
-      bool b = mut_process_buffer(node);
-      if (b) {
-        // True here means that the buffer hasn't been deallocated and the caller may reuse it.
-        return true;
-      }
-    }
-  }
-  // The buffer will be enqueued. The caller will have to get a new one.
-  enqueue_complete_buffer(node);
-  return false;
-}
-
-void PtrQueueSet::enqueue_complete_buffer(BufferNode* cbn) {
-  MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
-  cbn->set_next(NULL);
-  if (_completed_buffers_tail == NULL) {
-    assert(_completed_buffers_head == NULL, "Well-formedness");
-    _completed_buffers_head = cbn;
-    _completed_buffers_tail = cbn;
-  } else {
-    _completed_buffers_tail->set_next(cbn);
-    _completed_buffers_tail = cbn;
-  }
-  _n_completed_buffers++;
-
-  if (!_process_completed && _process_completed_threshold >= 0 &&
-      _n_completed_buffers >= (size_t)_process_completed_threshold) {
-    _process_completed = true;
-    if (_notify_when_complete) {
-      _cbl_mon->notify();
-    }
-  }
-  DEBUG_ONLY(assert_completed_buffer_list_len_correct_locked());
-}
-
-size_t PtrQueueSet::completed_buffers_list_length() {
-  size_t n = 0;
-  BufferNode* cbn = _completed_buffers_head;
-  while (cbn != NULL) {
-    n++;
-    cbn = cbn->next();
-  }
-  return n;
-}
-
-void PtrQueueSet::assert_completed_buffer_list_len_correct() {
-  MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
-  assert_completed_buffer_list_len_correct_locked();
-}
-
-void PtrQueueSet::assert_completed_buffer_list_len_correct_locked() {
-  guarantee(completed_buffers_list_length() ==  _n_completed_buffers,
-            "Completed buffer length is wrong.");
-}
-
-void PtrQueueSet::set_buffer_size(size_t sz) {
-  assert(_sz == 0 && sz > 0, "Should be called only once.");
-  _sz = sz * sizeof(void*);
-}
-
-// Merge lists of buffers. Notify the processing threads.
-// The source queue is emptied as a result. The queues
-// must share the monitor.
-void PtrQueueSet::merge_bufferlists(PtrQueueSet *src) {
-  assert(_cbl_mon == src->_cbl_mon, "Should share the same lock");
-  MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
-  if (_completed_buffers_tail == NULL) {
-    assert(_completed_buffers_head == NULL, "Well-formedness");
-    _completed_buffers_head = src->_completed_buffers_head;
-    _completed_buffers_tail = src->_completed_buffers_tail;
-  } else {
-    assert(_completed_buffers_head != NULL, "Well formedness");
-    if (src->_completed_buffers_head != NULL) {
-      _completed_buffers_tail->set_next(src->_completed_buffers_head);
-      _completed_buffers_tail = src->_completed_buffers_tail;
-    }
-  }
-  _n_completed_buffers += src->_n_completed_buffers;
-
-  src->_n_completed_buffers = 0;
-  src->_completed_buffers_head = NULL;
-  src->_completed_buffers_tail = NULL;
-
-  assert(_completed_buffers_head == NULL && _completed_buffers_tail == NULL ||
-         _completed_buffers_head != NULL && _completed_buffers_tail != NULL,
-         "Sanity");
-}
-
-void PtrQueueSet::notify_if_necessary() {
-  MutexLockerEx x(_cbl_mon, Mutex::_no_safepoint_check_flag);
-  assert(_process_completed_threshold >= 0, "_process_completed is negative");
-  if (_n_completed_buffers >= (size_t)_process_completed_threshold || _max_completed_queue == 0) {
-    _process_completed = true;
-    if (_notify_when_complete)
-      _cbl_mon->notify();
-  }
-}