view src/os_cpu/linux_x86/vm/threadLS_linux_x86.hpp @ 20304:a22acf6d7598

8048112: G1 Full GC needs to support the case when the very first region is not available Summary: Refactor preparation for compaction during Full GC so that it lazily initializes the first compaction point. This also avoids problems later when the first region may not be committed. Also reviewed by K. Barrett. Reviewed-by: brutisso
author tschatzl
date Mon, 21 Jul 2014 10:00:31 +0200
parents 65dba8692db7
children
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/*
 * Copyright (c) 1999, 2010, 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.
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 */

#ifndef OS_CPU_LINUX_X86_VM_THREADLS_LINUX_X86_HPP
#define OS_CPU_LINUX_X86_VM_THREADLS_LINUX_X86_HPP

  // Processor dependent parts of ThreadLocalStorage

#if !defined(AMD64) && !defined(MINIMIZE_RAM_USAGE)

  // map stack pointer to thread pointer - see notes in threadLS_linux_x86.cpp
  #define SP_BITLENGTH  32
  #define PAGE_SHIFT    12
  #define PAGE_SIZE     (1UL << PAGE_SHIFT)
  static Thread* _sp_map[1UL << (SP_BITLENGTH - PAGE_SHIFT)];

public:

  static Thread** sp_map_addr() { return _sp_map; }

  static Thread* thread() {
    uintptr_t sp;
    __asm__ volatile ("movl %%esp, %0" : "=r" (sp));
    return _sp_map[sp >> PAGE_SHIFT];
  }

#else

public:

   static Thread* thread() {
     return (Thread*) os::thread_local_storage_at(thread_index());
   }

#endif // AMD64 || MINIMIZE_RAM_USAGE

#endif // OS_CPU_LINUX_X86_VM_THREADLS_LINUX_X86_HPP