1 /*

     2  * Copyright (c) 2015, 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 "runtime/threadLocalStorage.hpp"

    27 #include <windows.h>

    28 

    29 static DWORD _thread_key;

    30 static bool _initialized = false;

    31 

    32 

    33 void ThreadLocalStorage::init() {

    34   assert(!_initialized, "initializing TLS more than once!");

    35   _thread_key = TlsAlloc();

    36   // If this assert fails we will get a recursive assertion failure

    37   // and not see the actual error message or get a hs_err file

    38   assert(_thread_key != TLS_OUT_OF_INDEXES, "TlsAlloc failed: out of indices");

    39   _initialized = true;

    40 }

    41 

    42 bool ThreadLocalStorage::is_initialized() {

    43   return _initialized;

    44 }

    45 

    46 Thread* ThreadLocalStorage::thread() {

    47   // If this assert fails we will get a recursive assertion failure

    48   // and not see the actual error message or get a hs_err file.

    49   // Which most likely indicates we have taken an error path early in

    50   // the initialization process, which is using Thread::current without

    51   // checking TLS is initialized - see java.cpp vm_exit

    52   assert(_initialized, "TLS not initialized yet!");

    53   Thread* current = (Thread*) TlsGetValue(_thread_key);

    54   assert(current != 0 || GetLastError() == ERROR_SUCCESS,

    55          "TlsGetValue failed with error code: %lu", GetLastError());

    56   return current;

    57 }

    58 

    59 void ThreadLocalStorage::set_thread(Thread* current) {

    60   assert(_initialized, "TLS not initialized yet!");

    61   BOOL res = TlsSetValue(_thread_key, current);

    62   assert(res, "TlsSetValue failed with error code: %lu", GetLastError());

    63 }