1 /*
   2  * Copyright (c) 2014, 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_implementation/g1/g1PageBasedVirtualSpace.hpp"
  27 #include "oops/markOop.hpp"
  28 #include "oops/oop.inline.hpp"
  29 #include "services/memTracker.hpp"
  30 #ifdef TARGET_OS_FAMILY_linux
  31 # include "os_linux.inline.hpp"
  32 #endif
  33 #ifdef TARGET_OS_FAMILY_solaris
  34 # include "os_solaris.inline.hpp"
  35 #endif
  36 #ifdef TARGET_OS_FAMILY_windows
  37 # include "os_windows.inline.hpp"
  38 #endif
  39 #ifdef TARGET_OS_FAMILY_aix
  40 # include "os_aix.inline.hpp"
  41 #endif
  42 #ifdef TARGET_OS_FAMILY_bsd
  43 # include "os_bsd.inline.hpp"
  44 #endif
  45 #include "utilities/bitMap.inline.hpp"
  46 
  47 G1PageBasedVirtualSpace::G1PageBasedVirtualSpace() : _low_boundary(NULL),
  48   _high_boundary(NULL), _committed(), _page_size(0), _special(false), _executable(false) {
  49 }
  50 
  51 bool G1PageBasedVirtualSpace::initialize_with_granularity(ReservedSpace rs, size_t page_size) {
  52   if (!rs.is_reserved()) {
  53     return false;  // Allocation failed.
  54   }
  55   assert(_low_boundary == NULL, "VirtualSpace already initialized");
  56   assert(page_size > 0, "Granularity must be non-zero.");
  57 
  58   _low_boundary  = rs.base();
  59   _high_boundary = _low_boundary + rs.size();
  60 
  61   _special = rs.special();
  62   _executable = rs.executable();
  63 
  64   _page_size = page_size;
  65 
  66   assert(_committed.size() == 0, "virtual space initialized more than once");
  67   uintx size_in_bits = rs.size() / page_size;
  68   _committed.resize(size_in_bits, /* in_resource_area */ false);
  69 
  70   return true;
  71 }
  72 
  73 
  74 G1PageBasedVirtualSpace::~G1PageBasedVirtualSpace() {
  75   release();
  76 }
  77 
  78 void G1PageBasedVirtualSpace::release() {
  79   // This does not release memory it never reserved.
  80   // Caller must release via rs.release();
  81   _low_boundary           = NULL;
  82   _high_boundary          = NULL;
  83   _special                = false;
  84   _executable             = false;
  85   _page_size              = 0;
  86   _committed.resize(0, false);
  87 }
  88 
  89 size_t G1PageBasedVirtualSpace::committed_size() const {
  90   return _committed.count_one_bits() * _page_size;
  91 }
  92 
  93 size_t G1PageBasedVirtualSpace::reserved_size() const {
  94   return pointer_delta(_high_boundary, _low_boundary, sizeof(char));
  95 }
  96 
  97 size_t G1PageBasedVirtualSpace::uncommitted_size()  const {
  98   return reserved_size() - committed_size();
  99 }
 100 
 101 uintptr_t G1PageBasedVirtualSpace::addr_to_page_index(char* addr) const {
 102   return (addr - _low_boundary) / _page_size;
 103 }
 104 
 105 bool G1PageBasedVirtualSpace::is_area_committed(uintptr_t start, size_t size_in_pages) const {
 106   uintptr_t end = start + size_in_pages;
 107   return _committed.get_next_zero_offset(start, end) >= end;
 108 }
 109 
 110 bool G1PageBasedVirtualSpace::is_area_uncommitted(uintptr_t start, size_t size_in_pages) const {
 111   uintptr_t end = start + size_in_pages;
 112   return _committed.get_next_one_offset(start, end) >= end;
 113 }
 114 
 115 char* G1PageBasedVirtualSpace::page_start(uintptr_t index) {
 116   return _low_boundary + index * _page_size;
 117 }
 118 
 119 size_t G1PageBasedVirtualSpace::byte_size_for_pages(size_t num) {
 120   return num * _page_size;
 121 }
 122 
 123 MemRegion G1PageBasedVirtualSpace::commit(uintptr_t start, size_t size_in_pages) {
 124   // We need to make sure to commit all pages covered by the given area.
 125   guarantee(is_area_uncommitted(start, size_in_pages), "Specified area is not uncommitted");
 126 
 127   if (!_special) {
 128     os::commit_memory_or_exit(page_start(start), byte_size_for_pages(size_in_pages), _executable,
 129                               err_msg("Failed to commit pages from "SIZE_FORMAT" of length "SIZE_FORMAT, start, size_in_pages));
 130   }
 131   _committed.set_range(start, start + size_in_pages);
 132 
 133   MemRegion result((HeapWord*)page_start(start), byte_size_for_pages(size_in_pages) / HeapWordSize);
 134   return result;
 135 }
 136 
 137 MemRegion G1PageBasedVirtualSpace::uncommit(uintptr_t start, size_t size_in_pages) {
 138   guarantee(is_area_committed(start, size_in_pages), "checking");
 139 
 140   if (!_special) {
 141     os::uncommit_memory(page_start(start), byte_size_for_pages(size_in_pages));
 142   }
 143 
 144   _committed.clear_range(start, start + size_in_pages);
 145 
 146   MemRegion result((HeapWord*)page_start(start), byte_size_for_pages(size_in_pages) / HeapWordSize);
 147   return result;
 148 }
 149 
 150 bool G1PageBasedVirtualSpace::contains(const void* p) const {
 151   return _low_boundary <= (const char*) p && (const char*) p < _high_boundary;
 152 }
 153 
 154 #ifndef PRODUCT
 155 void G1PageBasedVirtualSpace::print_on(outputStream* out) {
 156   out->print   ("Virtual space:");
 157   if (special()) out->print(" (pinned in memory)");
 158   out->cr();
 159   out->print_cr(" - committed: " SIZE_FORMAT, committed_size());
 160   out->print_cr(" - reserved:  " SIZE_FORMAT, reserved_size());
 161   out->print_cr(" - [low_b, high_b]: [" INTPTR_FORMAT ", " INTPTR_FORMAT "]",  p2i(_low_boundary), p2i(_high_boundary));
 162 }
 163 
 164 void G1PageBasedVirtualSpace::print() {
 165   print_on(tty);
 166 }
 167 #endif