jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/concurrentMarkSweep/cmsLockVerifier.cpp@4947ee68d19c

7008136: CMS: assert((HeapWord*)nextChunk <= _limit) failed: sweep invariant
Summary: The recorded _sweep_limit may not necessarily remain a block boundary as the old generation expands during a concurrent cycle. Terminal actions inside the sweep closure need to be aware of this as they cross over the limit.
Reviewed-by: johnc, minqi

     1 /*

     2  * Copyright (c) 2002, 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  */

    25 #include "precompiled.hpp"

    26 #include "gc_implementation/concurrentMarkSweep/cmsLockVerifier.hpp"

    27 #include "gc_implementation/concurrentMarkSweep/concurrentMarkSweepThread.hpp"

    28 #include "runtime/vmThread.hpp"

    30 ///////////// Locking verification specific to CMS //////////////

    31 // Much like "assert_lock_strong()", except that it relaxes the

    32 // assertion somewhat for the parallel GC case, where VM thread

    33 // or the CMS thread might hold the lock on behalf of the parallel

    34 // threads. The second argument is in support of an extra locking

    35 // check for CFL spaces' free list locks.

    36 #ifndef PRODUCT

    37 void CMSLockVerifier::assert_locked(const Mutex* lock,

    38                                     const Mutex* p_lock1,

    39                                     const Mutex* p_lock2) {

    40   if (!Universe::is_fully_initialized()) {

    41     return;

    42   }

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

    46   if (lock == NULL) { // a "lock-free" structure, e.g. MUT, protected by CMS token

    47     assert(p_lock1 == NULL && p_lock2 == NULL, "Unexpected caller error");

    48     if (myThread->is_ConcurrentGC_thread()) {

    49       // This test might have to change in the future, if there can be

    50       // multiple peer CMS threads.  But for now, if we're testing the CMS

    51       assert(myThread == ConcurrentMarkSweepThread::cmst(),

    52              "In CMS, CMS thread is the only Conc GC thread.");

    53       assert(ConcurrentMarkSweepThread::cms_thread_has_cms_token(),

    54              "CMS thread should have CMS token");

    55     } else if (myThread->is_VM_thread()) {

    56       assert(ConcurrentMarkSweepThread::vm_thread_has_cms_token(),

    57              "VM thread should have CMS token");

    58     } else {

    59       // Token should be held on our behalf by one of the other

    60       // of CMS or VM thread; not enough easily testable

    61       // state info to test which here.

    62       assert(myThread->is_GC_task_thread(), "Unexpected thread type");

    63     }

    64     return;

    65   }

    67   if (myThread->is_VM_thread()

    68       || myThread->is_ConcurrentGC_thread()

    69       || myThread->is_Java_thread()) {

    70     // Make sure that we are holding the associated lock.

    71     assert_lock_strong(lock);

    72     // The checking of p_lock is a spl case for CFLS' free list

    73     // locks: we make sure that none of the parallel GC work gang

    74     // threads are holding "sub-locks" of freeListLock(). We check only

    75     // the parDictionaryAllocLock because the others are too numerous.

    76     // This spl case code is somewhat ugly and any improvements

    77     // are welcome.

    78     assert(p_lock1 == NULL || !p_lock1->is_locked() || p_lock1->owned_by_self(),

    79            "Possible race between this and parallel GC threads");

    80     assert(p_lock2 == NULL || !p_lock2->is_locked() || p_lock2->owned_by_self(),

    81            "Possible race between this and parallel GC threads");

    82   } else if (myThread->is_GC_task_thread()) {

    83     // Make sure that the VM or CMS thread holds lock on our behalf

    84     // XXX If there were a concept of a gang_master for a (set of)

    85     // gang_workers, we could have used the identity of that thread

    86     // for checking ownership here; for now we just disjunct.

    87     assert(lock->owner() == VMThread::vm_thread() ||

    88            lock->owner() == ConcurrentMarkSweepThread::cmst(),

    89            "Should be locked by VM thread or CMS thread on my behalf");

    90     if (p_lock1 != NULL) {

    91       assert_lock_strong(p_lock1);

    92     }

    93     if (p_lock2 != NULL) {

    94       assert_lock_strong(p_lock2);

    95     }

    96   } else {

    97     // Make sure we didn't miss some other thread type calling into here;

    98     // perhaps as a result of future VM evolution.

    99     ShouldNotReachHere();

   100   }

   101 }

   102 #endif

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

src/share/vm/gc_implementation/concurrentMarkSweep/cmsLockVerifier.cpp@4947ee68d19c

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