jdk8-mips64-public/hotspot: src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.hpp@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 /*

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     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

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    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

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    25 #ifndef SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_CMSPERMGEN_HPP

    26 #define SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_CMSPERMGEN_HPP

    28 #include "gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.hpp"

    29 #include "memory/permGen.hpp"

    31 class CardTableRS;   // fwd decl

    32 class ConcurrentMarkSweepGeneration;

    34 // A PermGen implemented with a CMS space, collected by a CMS collector.

    35 class CMSPermGen:  public PermGen {

    36   friend class VMStructs;

    38  protected:

    39   // The "generation" view.

    40   ConcurrentMarkSweepGeneration* _gen;

    42   // Override default implementation from PermGen

    43   virtual HeapWord* request_expand_and_allocate(Generation* gen, size_t size,

    44                                                 GCCause::Cause prev_cause);

    46  public:

    47   CMSPermGen(ReservedSpace rs, size_t initial_byte_size,

    48              CardTableRS* ct, FreeBlockDictionary::DictionaryChoice);

    50   HeapWord* mem_allocate(size_t size);

    52   void compute_new_size();

    54   Generation* as_gen() const { return _gen; }

    55 };

    57 // This is the "generation" view of a CMSPermGen.

    58 class CMSPermGenGen: public ConcurrentMarkSweepGeneration {

    59   // Abstractly, this is a subtype that gets access to protected fields.

    60   friend class CMSPermGen;

    61 public:

    62   CMSPermGenGen(ReservedSpace rs, size_t initial_byte_size,

    63                        int level, CardTableRS* ct):

    64     // See comments in the constructor for CompactibleFreeListSpace

    65     // regarding not using adaptive free lists for a perm gen.

    66     ConcurrentMarkSweepGeneration(rs, initial_byte_size, // MinPermHeapExapnsion

    67       level, ct, false /* use adaptive freelists */,

    68       (FreeBlockDictionary::DictionaryChoice)CMSDictionaryChoice)

    69   {}

    71   void initialize_performance_counters();

    73   const char* name() const {

    74     return "concurrent-mark-sweep perm gen";

    75   }

    77   const char* short_name() const {

    78     return "CMS Perm";

    79   }

    81   bool must_be_youngest() const { return false; }

    82   bool must_be_oldest() const { return false; }

    83 };

    85 #endif // SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_CMSPERMGEN_HPP

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

src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.hpp@4947ee68d19c

src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.hpp