jdk8-mips64-public/hotspot: src/share/vm/oops/methodDataKlass.hpp@e1162778c1c8

7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error
Summary: A referent object that is only weakly reachable at the start of concurrent marking but is re-attached to the strongly reachable object graph during marking may not be marked as live. This can cause the reference object to be processed prematurely and leave dangling pointers to the referent object. Implement a read barrier for the java.lang.ref.Reference::referent field by intrinsifying the Reference.get() method, and intercepting accesses though JNI, reflection, and Unsafe, so that when a non-null referent object is read it is also logged in an SATB buffer.
Reviewed-by: kvn, iveresov, never, tonyp, dholmes

     1 /*

     2  * Copyright (c) 2000, 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

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    23  */

    25 #ifndef SHARE_VM_OOPS_METHODDATAKLASS_HPP

    26 #define SHARE_VM_OOPS_METHODDATAKLASS_HPP

    28 #include "oops/klass.hpp"

    30 // a methodDataKlass is the klass of a methodDataOop

    32 class methodDataKlass : public Klass {

    33   friend class VMStructs;

    34  private:

    35   juint _alloc_size; // allocation profiling support

    36  public:

    37   // Testing

    38   bool oop_is_methodData() const { return true; }

    40   // Allocation

    41   DEFINE_ALLOCATE_PERMANENT(methodDataKlass);

    42   methodDataOop allocate(methodHandle method, TRAPS);

    43   static klassOop create_klass(TRAPS);

    45   // Sizing

    46   int oop_size(oop obj) const;

    47   int klass_oop_size() const { return object_size(); }

    49   // Casting from klassOop

    50   static methodDataKlass* cast(klassOop k) {

    51     assert(k->klass_part()->oop_is_methodData(), "cast to methodDataKlass");

    52     return (methodDataKlass*) k->klass_part();

    53   }

    55   // Sizing

    56   static int header_size() {

    57     return oopDesc::header_size() + sizeof(methodDataKlass)/wordSize;

    58   }

    59   int object_size() const {

    60     return align_object_size(header_size());

    61   }

    63   // Garbage collection

    64   void oop_follow_contents(oop obj);

    65   int  oop_adjust_pointers(oop obj);

    66   bool oop_is_parsable(oop obj) const;

    68   // Parallel Scavenge and Parallel Old

    69   PARALLEL_GC_DECLS

    71   // Allocation profiling support

    72   juint alloc_size() const { return _alloc_size; }

    73   void  set_alloc_size(juint n) { _alloc_size = n; }

    75   // Iterators

    76   int oop_oop_iterate(oop obj, OopClosure* blk);

    77   int oop_oop_iterate_m(oop obj, OopClosure* blk, MemRegion mr);

    79  public:

    80   // Printing

    81   void oop_print_value_on(oop obj, outputStream* st);

    82 #ifndef PRODUCT

    83   void oop_print_on      (oop obj, outputStream* st);

    84 #endif //PRODUCT

    86   // Verify operations

    87   const char* internal_name() const;

    88   void oop_verify_on(oop obj, outputStream* st);

    89 };

    91 #endif // SHARE_VM_OOPS_METHODDATAKLASS_HPP

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

src/share/vm/oops/methodDataKlass.hpp@e1162778c1c8

src/share/vm/oops/methodDataKlass.hpp