view src/share/vm/memory/blockOffsetTable.inline.hpp @ 20543:e7d0505c8a30

8059758: Footprint regressions with JDK-8038423 Summary: Changes in JDK-8038423 always initialize (zero out) virtual memory used for auxiliary data structures. This causes a footprint regression for G1 in startup benchmarks. This is because they do not touch that memory at all, so the operating system does not actually commit these pages. The fix is to, if the initialization value of the data structures matches the default value of just committed memory (=0), do not do anything. Reviewed-by: jwilhelm, brutisso
author tschatzl
date Fri, 10 Oct 2014 15:51:58 +0200
parents da91efe96a93
children
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/*
 * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

#ifndef SHARE_VM_MEMORY_BLOCKOFFSETTABLE_INLINE_HPP
#define SHARE_VM_MEMORY_BLOCKOFFSETTABLE_INLINE_HPP

#include "memory/blockOffsetTable.hpp"
#include "memory/space.hpp"
#include "runtime/safepoint.hpp"

//////////////////////////////////////////////////////////////////////////
// BlockOffsetTable inlines
//////////////////////////////////////////////////////////////////////////
inline HeapWord* BlockOffsetTable::block_start(const void* addr) const {
  if (addr >= _bottom && addr < _end) {
    return block_start_unsafe(addr);
  } else {
    return NULL;
  }
}

//////////////////////////////////////////////////////////////////////////
// BlockOffsetSharedArray inlines
//////////////////////////////////////////////////////////////////////////
inline size_t BlockOffsetSharedArray::index_for(const void* p) const {
  char* pc = (char*)p;
  assert(pc >= (char*)_reserved.start() &&
         pc <  (char*)_reserved.end(),
         "p not in range.");
  size_t delta = pointer_delta(pc, _reserved.start(), sizeof(char));
  size_t result = delta >> LogN;
  assert(result < _vs.committed_size(), "bad index from address");
  return result;
}

inline HeapWord* BlockOffsetSharedArray::address_for_index(size_t index) const {
  assert(index < _vs.committed_size(), "bad index");
  HeapWord* result = _reserved.start() + (index << LogN_words);
  assert(result >= _reserved.start() && result < _reserved.end(),
         "bad address from index");
  return result;
}

inline void BlockOffsetSharedArray::check_reducing_assertion(bool reducing) {
    assert(reducing || !SafepointSynchronize::is_at_safepoint() || init_to_zero() ||
           Thread::current()->is_VM_thread() ||
           Thread::current()->is_ConcurrentGC_thread() ||
           ((!Thread::current()->is_ConcurrentGC_thread()) &&
            ParGCRareEvent_lock->owned_by_self()), "Crack");
}

//////////////////////////////////////////////////////////////////////////
// BlockOffsetArrayNonContigSpace inlines
//////////////////////////////////////////////////////////////////////////
inline void BlockOffsetArrayNonContigSpace::freed(HeapWord* blk,
                                                  size_t size) {
  freed(blk, blk + size);
}

inline void BlockOffsetArrayNonContigSpace::freed(HeapWord* blk_start,
                                                  HeapWord* blk_end) {
  // Verify that the BOT shows [blk_start, blk_end) to be one block.
  verify_single_block(blk_start, blk_end);
  // adjust _unallocated_block upward or downward
  // as appropriate
  if (BlockOffsetArrayUseUnallocatedBlock) {
    assert(_unallocated_block <= _end,
           "Inconsistent value for _unallocated_block");
    if (blk_end >= _unallocated_block && blk_start <= _unallocated_block) {
      // CMS-specific note: a block abutting _unallocated_block to
      // its left is being freed, a new block is being added or
      // we are resetting following a compaction
      _unallocated_block = blk_start;
    }
  }
}

#endif // SHARE_VM_MEMORY_BLOCKOFFSETTABLE_INLINE_HPP