1 /*

     2  * Copyright (c) 1999, 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 #ifndef OS_CPU_LINUX_X86_VM_THREADLS_LINUX_X86_HPP

    26 #define OS_CPU_LINUX_X86_VM_THREADLS_LINUX_X86_HPP

    27 

    28   // Processor dependent parts of ThreadLocalStorage

    29 

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

    31 

    32   // map stack pointer to thread pointer - see notes in threadLS_linux_x86.cpp

    33   #define SP_BITLENGTH  32

    34   #define PAGE_SHIFT    12

    35   #define PAGE_SIZE     (1UL << PAGE_SHIFT)

    36   static Thread* _sp_map[1UL << (SP_BITLENGTH - PAGE_SHIFT)];

    37 

    38 public:

    39 

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

    41 

    42   static Thread* thread() {

    43     uintptr_t sp;

    44     __asm__ volatile ("movl %%esp, %0" : "=r" (sp));

    45     return _sp_map[sp >> PAGE_SHIFT];

    46   }

    47 

    48 #else

    49 

    50 public:

    51 

    52    static Thread* thread() {

    53      return (Thread*) os::thread_local_storage_at(thread_index());

    54    }

    55 

    56 #endif // AMD64 || MINIMIZE_RAM_USAGE

    57 

    58 #endif // OS_CPU_LINUX_X86_VM_THREADLS_LINUX_X86_HPP