1 /*
   2  * Copyright (c) 2005, 2009, 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 "incls/_precompiled.incl"
  26 # include "incls/_biasedLocking.cpp.incl"







  27 
  28 static bool _biased_locking_enabled = false;
  29 BiasedLockingCounters BiasedLocking::_counters;
  30 
  31 static GrowableArray<Handle>*  _preserved_oop_stack  = NULL;
  32 static GrowableArray<markOop>* _preserved_mark_stack = NULL;
  33 
  34 static void enable_biased_locking(klassOop k) {
  35   Klass::cast(k)->set_prototype_header(markOopDesc::biased_locking_prototype());
  36 }
  37 
  38 class VM_EnableBiasedLocking: public VM_Operation {
  39  private:
  40   bool _is_cheap_allocated;
  41  public:
  42   VM_EnableBiasedLocking(bool is_cheap_allocated) { _is_cheap_allocated = is_cheap_allocated; }
  43   VMOp_Type type() const          { return VMOp_EnableBiasedLocking; }
  44   Mode evaluation_mode() const    { return _is_cheap_allocated ? _async_safepoint : _safepoint; }
  45   bool is_cheap_allocated() const { return _is_cheap_allocated; }
  46 

   1 /*
   2  * Copyright (c) 2005, 2010, 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 "oops/klass.inline.hpp"
  27 #include "oops/markOop.hpp"
  28 #include "runtime/biasedLocking.hpp"
  29 #include "runtime/synchronizer.hpp"
  30 #include "runtime/task.hpp"
  31 #include "runtime/vframe.hpp"
  32 #include "runtime/vmThread.hpp"
  33 #include "runtime/vm_operations.hpp"
  34 
  35 static bool _biased_locking_enabled = false;
  36 BiasedLockingCounters BiasedLocking::_counters;
  37 
  38 static GrowableArray<Handle>*  _preserved_oop_stack  = NULL;
  39 static GrowableArray<markOop>* _preserved_mark_stack = NULL;
  40 
  41 static void enable_biased_locking(klassOop k) {
  42   Klass::cast(k)->set_prototype_header(markOopDesc::biased_locking_prototype());
  43 }
  44 
  45 class VM_EnableBiasedLocking: public VM_Operation {
  46  private:
  47   bool _is_cheap_allocated;
  48  public:
  49   VM_EnableBiasedLocking(bool is_cheap_allocated) { _is_cheap_allocated = is_cheap_allocated; }
  50   VMOp_Type type() const          { return VMOp_EnableBiasedLocking; }
  51   Mode evaluation_mode() const    { return _is_cheap_allocated ? _async_safepoint : _safepoint; }
  52   bool is_cheap_allocated() const { return _is_cheap_allocated; }
  53