view src/share/vm/runtime/threadLocalStorage.hpp @ 1716:be3f9c242c9d

6948538: CMS: BOT walkers can fall into object allocation and initialization cracks Summary: GC workers now recognize an intermediate transient state of blocks which are allocated but have not yet completed initialization. blk_start() calls do not attempt to determine the size of a block in the transient state, rather waiting for the block to become initialized so that it is safe to query its size. Audited and ensured the order of initialization of object fields (klass, free bit and size) to respect block state transition protocol. Also included some new assertion checking code enabled in debug mode. Reviewed-by: chrisphi, johnc, poonam
author ysr
date Mon, 16 Aug 2010 15:58:42 -0700
parents c18cbe5936b8
children f95d63e2154a
line wrap: on
line source

/*
 * Copyright (c) 1997, 2008, 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.
 *
 */

// Interface for thread local storage

// Fast variant of ThreadLocalStorage::get_thread_slow
extern "C" Thread*   get_thread();

// Get raw thread id: e.g., %g7 on sparc, fs or gs on x86
extern "C" uintptr_t _raw_thread_id();

class ThreadLocalStorage : AllStatic {
 public:
  static void    set_thread(Thread* thread);
  static Thread* get_thread_slow();
  static void    invalidate_all() { pd_invalidate_all(); }

  // Machine dependent stuff
  #include "incls/_threadLS_pd.hpp.incl"

 public:
  // Accessor
  static inline int  thread_index()              { return _thread_index; }
  static inline void set_thread_index(int index) { _thread_index = index; }

  // Initialization
  // Called explicitly from VMThread::activate_system instead of init_globals.
  static void init();
  static bool is_initialized();

 private:
  static int     _thread_index;

  static void    generate_code_for_get_thread();

  // Processor dependent parts of set_thread and initialization
  static void pd_set_thread(Thread* thread);
  static void pd_init();
  // Invalidate any thread cacheing or optimization schemes.
  static void pd_invalidate_all();

};