1 /*
   2  * Copyright (c) 2011, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_GC_G1_HEAPREGIONSET_INLINE_HPP
  26 #define SHARE_VM_GC_G1_HEAPREGIONSET_INLINE_HPP
  27 
  28 #include "gc/g1/heapRegionSet.hpp"
  29 
  30 inline void HeapRegionSetBase::add(HeapRegion* hr) {
  31   check_mt_safety();
  32   assert_heap_region_set(hr->containing_set() == NULL, "should not already have a containing set");
  33   assert_heap_region_set(hr->next() == NULL, "should not already be linked");
  34   assert_heap_region_set(hr->prev() == NULL, "should not already be linked");
  35 
  36   _count.increment(1u, hr->capacity());
  37   hr->set_containing_set(this);
  38   verify_region(hr);
  39 }
  40 
  41 inline void HeapRegionSetBase::remove(HeapRegion* hr) {
  42   check_mt_safety();
  43   verify_region(hr);
  44   assert_heap_region_set(hr->next() == NULL, "should already be unlinked");
  45   assert_heap_region_set(hr->prev() == NULL, "should already be unlinked");
  46 
  47   hr->set_containing_set(NULL);
  48   assert_heap_region_set(_count.length() > 0, "pre-condition");
  49   _count.decrement(1u, hr->capacity());
  50 }
  51 
  52 inline void FreeRegionList::add_ordered(HeapRegion* hr) {
  53   assert_free_region_list((length() == 0 && _head == NULL && _tail == NULL && _last == NULL) ||
  54                           (length() >  0 && _head != NULL && _tail != NULL),
  55                           "invariant");
  56   // add() will verify the region and check mt safety.
  57   add(hr);
  58 
  59   // Now link the region
  60   if (_head != NULL) {
  61     HeapRegion* curr;
  62 
  63     if (_last != NULL && _last->hrm_index() < hr->hrm_index()) {
  64       curr = _last;
  65     } else {
  66       curr = _head;
  67     }
  68 
  69     // Find first entry with a Region Index larger than entry to insert.
  70     while (curr != NULL && curr->hrm_index() < hr->hrm_index()) {
  71       curr = curr->next();
  72     }
  73 
  74     hr->set_next(curr);
  75 
  76     if (curr == NULL) {
  77       // Adding at the end
  78       hr->set_prev(_tail);
  79       _tail->set_next(hr);
  80       _tail = hr;
  81     } else if (curr->prev() == NULL) {
  82       // Adding at the beginning
  83       hr->set_prev(NULL);
  84       _head = hr;
  85       curr->set_prev(hr);
  86     } else {
  87       hr->set_prev(curr->prev());
  88       hr->prev()->set_next(hr);
  89       curr->set_prev(hr);
  90     }
  91   } else {
  92     // The list was empty
  93     _tail = hr;
  94     _head = hr;
  95   }
  96   _last = hr;
  97 }
  98 
  99 inline HeapRegion* FreeRegionList::remove_from_head_impl() {
 100   HeapRegion* result = _head;
 101   _head = result->next();
 102   if (_head == NULL) {
 103     _tail = NULL;
 104   } else {
 105     _head->set_prev(NULL);
 106   }
 107   result->set_next(NULL);
 108   return result;
 109 }
 110 
 111 inline HeapRegion* FreeRegionList::remove_from_tail_impl() {
 112   HeapRegion* result = _tail;
 113 
 114   _tail = result->prev();
 115   if (_tail == NULL) {
 116     _head = NULL;
 117   } else {
 118     _tail->set_next(NULL);
 119   }
 120   result->set_prev(NULL);
 121   return result;
 122 }
 123 
 124 inline HeapRegion* FreeRegionList::remove_region(bool from_head) {
 125   check_mt_safety();
 126   verify_optional();
 127 
 128   if (is_empty()) {
 129     return NULL;
 130   }
 131   assert_free_region_list(length() > 0 && _head != NULL && _tail != NULL, "invariant");
 132 
 133   HeapRegion* hr;
 134 
 135   if (from_head) {
 136     hr = remove_from_head_impl();
 137   } else {
 138     hr = remove_from_tail_impl();
 139   }
 140 
 141   if (_last == hr) {
 142     _last = NULL;
 143   }
 144 
 145   // remove() will verify the region and check mt safety.
 146   remove(hr);
 147   return hr;
 148 }
 149 
 150 #endif // SHARE_VM_GC_G1_HEAPREGIONSET_INLINE_HPP
 151