1 /*
   2  * Copyright (c) 2003, 2018, 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 #include "precompiled.hpp"
  26 #include "gc/parallel/adjoiningVirtualSpaces.hpp"
  27 #include "memory/allocation.inline.hpp"
  28 #include "runtime/java.hpp"
  29 
  30 AdjoiningVirtualSpaces::AdjoiningVirtualSpaces(ReservedSpace rs,
  31                                                size_t min_low_byte_size,
  32                                                size_t min_high_byte_size,
  33                                                size_t alignment) :
  34   _reserved_space(rs), _min_low_byte_size(min_low_byte_size),
  35   _min_high_byte_size(min_high_byte_size), _low(0), _high(0),
  36   _alignment(alignment) {}
  37 
  38 // The maximum byte sizes are for the initial layout of the
  39 // virtual spaces and are not the limit on the maximum bytes sizes.
  40 void AdjoiningVirtualSpaces::initialize(size_t max_low_byte_size,
  41                                         size_t init_low_byte_size,
  42                                         size_t init_high_byte_size) {
  43 
  44   // The reserved spaces for the two parts of the virtual space.
  45   ReservedSpace old_rs   = _reserved_space.first_part(max_low_byte_size);
  46   ReservedSpace young_rs = _reserved_space.last_part(max_low_byte_size);
  47 
  48   _low = new PSVirtualSpace(old_rs, alignment());
  49   if (os::has_nvdimm() && UseParallelOldGC) {
  50     if (!_low->expand_by(init_low_byte_size, _nvdimm_fd)) {
  51       vm_exit_during_initialization("Could not reserve enough space for "
  52                                     "object heap");
  53     }
  54   } else {
  55     if (!_low->expand_by(init_low_byte_size)) {
  56       vm_exit_during_initialization("Could not reserve enough space for "
  57                                     "object heap");
  58     }
  59   }
  60 
  61   _high = new PSVirtualSpaceHighToLow(young_rs, alignment());
  62   if (!_high->expand_by(init_high_byte_size)) {
  63     vm_exit_during_initialization("Could not reserve enough space for "
  64                                   "object heap");
  65   }
  66 }
  67 
  68 bool AdjoiningVirtualSpaces::adjust_boundary_up(size_t change_in_bytes) {
  69   assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");
  70   size_t actual_change = 0;
  71   if (os::has_nvdimm() && UseParallelOldGC) {
  72     actual_change = low()->expand_into(high(), change_in_bytes, nvdimm_fd());
  73   } else {
  74     actual_change = low()->expand_into(high(), change_in_bytes);
  75   }
  76   return actual_change != 0;
  77 }
  78 
  79 bool AdjoiningVirtualSpaces::adjust_boundary_down(size_t change_in_bytes) {
  80   assert(UseAdaptiveSizePolicy && UseAdaptiveGCBoundary, "runtime check");
  81   size_t actual_change = high()->expand_into(low(), change_in_bytes);
  82   return actual_change != 0;
  83 }