src/share/vm/gc_implementation/g1/g1BlockOffsetTable.inline.hpp

Mon, 07 Jul 2014 10:12:40 +0200

author
stefank
date
Mon, 07 Jul 2014 10:12:40 +0200
changeset 6992
2c6ef90f030a
parent 6990
1526a938e670
child 7051
1f1d373cd044
permissions
-rw-r--r--

8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com

     1 /*
     2  * Copyright (c) 2001, 2014, 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 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1BLOCKOFFSETTABLE_INLINE_HPP
    26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1BLOCKOFFSETTABLE_INLINE_HPP
    28 #include "gc_implementation/g1/g1BlockOffsetTable.hpp"
    29 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
    30 #include "gc_implementation/g1/heapRegion.inline.hpp"
    31 #include "memory/space.hpp"
    33 inline HeapWord* G1BlockOffsetTable::block_start(const void* addr) {
    34   if (addr >= _bottom && addr < _end) {
    35     return block_start_unsafe(addr);
    36   } else {
    37     return NULL;
    38   }
    39 }
    41 inline HeapWord*
    42 G1BlockOffsetTable::block_start_const(const void* addr) const {
    43   if (addr >= _bottom && addr < _end) {
    44     return block_start_unsafe_const(addr);
    45   } else {
    46     return NULL;
    47   }
    48 }
    50 inline size_t G1BlockOffsetSharedArray::index_for(const void* p) const {
    51   char* pc = (char*)p;
    52   assert(pc >= (char*)_reserved.start() &&
    53          pc <  (char*)_reserved.end(),
    54          err_msg("p (" PTR_FORMAT ") not in reserved [" PTR_FORMAT ", " PTR_FORMAT ")",
    55                  p2i(p), p2i(_reserved.start()), p2i(_reserved.end())));
    56   size_t delta = pointer_delta(pc, _reserved.start(), sizeof(char));
    57   size_t result = delta >> LogN;
    58   check_index(result, "bad index from address");
    59   return result;
    60 }
    62 inline HeapWord*
    63 G1BlockOffsetSharedArray::address_for_index(size_t index) const {
    64   check_index(index, "index out of range");
    65   HeapWord* result = _reserved.start() + (index << LogN_words);
    66   assert(result >= _reserved.start() && result < _reserved.end(),
    67          err_msg("bad address from index result " PTR_FORMAT
    68                  " _reserved.start() " PTR_FORMAT " _reserved.end() "
    69                  PTR_FORMAT,
    70                  p2i(result), p2i(_reserved.start()), p2i(_reserved.end())));
    71   return result;
    72 }
    74 inline size_t
    75 G1BlockOffsetArray::block_size(const HeapWord* p) const {
    76   return gsp()->block_size(p);
    77 }
    79 inline HeapWord*
    80 G1BlockOffsetArray::block_at_or_preceding(const void* addr,
    81                                           bool has_max_index,
    82                                           size_t max_index) const {
    83   assert(_array->offset_array(0) == 0, "objects can't cross covered areas");
    84   size_t index = _array->index_for(addr);
    85   // We must make sure that the offset table entry we use is valid.  If
    86   // "addr" is past the end, start at the last known one and go forward.
    87   if (has_max_index) {
    88     index = MIN2(index, max_index);
    89   }
    90   HeapWord* q = _array->address_for_index(index);
    92   uint offset = _array->offset_array(index);  // Extend u_char to uint.
    93   while (offset >= N_words) {
    94     // The excess of the offset from N_words indicates a power of Base
    95     // to go back by.
    96     size_t n_cards_back = BlockOffsetArray::entry_to_cards_back(offset);
    97     q -= (N_words * n_cards_back);
    98     assert(q >= gsp()->bottom(), "Went below bottom!");
    99     index -= n_cards_back;
   100     offset = _array->offset_array(index);
   101   }
   102   assert(offset < N_words, "offset too large");
   103   q -= offset;
   104   return q;
   105 }
   107 inline HeapWord*
   108 G1BlockOffsetArray::
   109 forward_to_block_containing_addr_const(HeapWord* q, HeapWord* n,
   110                                        const void* addr) const {
   111   if (addr >= gsp()->top()) return gsp()->top();
   112   while (n <= addr) {
   113     q = n;
   114     oop obj = oop(q);
   115     if (obj->klass_or_null() == NULL) return q;
   116     n += block_size(q);
   117   }
   118   assert(q <= n, "wrong order for q and addr");
   119   assert(addr < n, "wrong order for addr and n");
   120   return q;
   121 }
   123 inline HeapWord*
   124 G1BlockOffsetArray::forward_to_block_containing_addr(HeapWord* q,
   125                                                      const void* addr) {
   126   if (oop(q)->klass_or_null() == NULL) return q;
   127   HeapWord* n = q + block_size(q);
   128   // In the normal case, where the query "addr" is a card boundary, and the
   129   // offset table chunks are the same size as cards, the block starting at
   130   // "q" will contain addr, so the test below will fail, and we'll fall
   131   // through quickly.
   132   if (n <= addr) {
   133     q = forward_to_block_containing_addr_slow(q, n, addr);
   134   }
   135   assert(q <= addr, "wrong order for current and arg");
   136   return q;
   137 }
   139 //////////////////////////////////////////////////////////////////////////
   140 // BlockOffsetArrayNonContigSpace inlines
   141 //////////////////////////////////////////////////////////////////////////
   142 inline void G1BlockOffsetArray::freed(HeapWord* blk_start, HeapWord* blk_end) {
   143   // Verify that the BOT shows [blk_start, blk_end) to be one block.
   144   verify_single_block(blk_start, blk_end);
   145   // adjust _unallocated_block upward or downward
   146   // as appropriate
   147   if (BlockOffsetArrayUseUnallocatedBlock) {
   148     assert(_unallocated_block <= _end,
   149            "Inconsistent value for _unallocated_block");
   150     if (blk_end >= _unallocated_block && blk_start <= _unallocated_block) {
   151       // CMS-specific note: a block abutting _unallocated_block to
   152       // its left is being freed, a new block is being added or
   153       // we are resetting following a compaction
   154       _unallocated_block = blk_start;
   155     }
   156   }
   157 }
   159 inline void G1BlockOffsetArray::freed(HeapWord* blk, size_t size) {
   160   freed(blk, blk + size);
   161 }
   163 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1BLOCKOFFSETTABLE_INLINE_HPP

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