jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/concurrentMarkSweep/freeBlockDictionary.cpp@3bfae429e2cf

6948537: CMS: BOT walkers observe out-of-thin-air zeros on sun4v sparc/CMT
Summary: On sun4v/CMT avoid use of memset() in BOT updates so as to prevent concurrent BOT readers from seeing the phantom zeros arising from memset()'s use of BIS.
Reviewed-by: jmasa, johnc, minqi, poonam, tonyp

     1 /*

     2  * Copyright 2002-2004 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    20  * CA 95054 USA or visit www.sun.com if you need additional information or

    21  * have any questions.

    22  *

    23  */

    25 # include "incls/_precompiled.incl"

    26 # include "incls/_freeBlockDictionary.cpp.incl"

    28 #ifndef PRODUCT

    29 Mutex* FreeBlockDictionary::par_lock() const {

    30   return _lock;

    31 }

    33 void FreeBlockDictionary::set_par_lock(Mutex* lock) {

    34   _lock = lock;

    35 }

    37 void FreeBlockDictionary::verify_par_locked() const {

    38 #ifdef ASSERT

    39   if (ParallelGCThreads > 0) {

    40     Thread* myThread = Thread::current();

    41     if (myThread->is_GC_task_thread()) {

    42       assert(par_lock() != NULL, "Should be using locking?");

    43       assert_lock_strong(par_lock());

    44     }

    45   }

    46 #endif // ASSERT

    47 }

    48 #endif

Mercurial > jdk8-mips64-public > hotspot / file revision

src/share/vm/gc_implementation/concurrentMarkSweep/freeBlockDictionary.cpp@3bfae429e2cf

src/share/vm/gc_implementation/concurrentMarkSweep/freeBlockDictionary.cpp