view src/share/vm/memory/barrierSet.cpp @ 12301:2c022e432e10

8024974: Incorrect use of GC_locker::is_active() Summary: SymbolTable and StringTable can make calls to GC_locker::is_active() outside a safepoint. This isn't safe because the GC_locker active state (lock count) is only updated at a safepoint and only remains valid as long as _needs_gc is true. However, outside a safepoint_needs_gc can change to false at any time, which makes it impossible to do a correct call to is_active() in that context. In this case these calls can just be removed since the input argument to basic_add() should never be on the heap and so there's no need to check the GC_locker state. This change also adjusts the assert() in is_active() to makes sure all calls to this function are always done under a safepoint. Reviewed-by: brutisso, dcubed Contributed-by: per.liden@oracle.com
author stefank
date Fri, 20 Sep 2013 10:53:28 +0200
parents 1d1603768966
children
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/*
 * Copyright (c) 1997, 2011, 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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 */

#include "precompiled.hpp"
#include "gc_interface/collectedHeap.hpp"
#include "memory/barrierSet.inline.hpp"
#include "memory/universe.hpp"

// count is number of array elements being written
void BarrierSet::static_write_ref_array_pre(HeapWord* start, size_t count) {
  assert(count <= (size_t)max_intx, "count too large");
#if 0
  warning("Pre: \t" INTPTR_FORMAT "[" SIZE_FORMAT "]\t",
                   start,            count);
#endif
  if (UseCompressedOops) {
    Universe::heap()->barrier_set()->write_ref_array_pre((narrowOop*)start, (int)count, false);
  } else {
    Universe::heap()->barrier_set()->write_ref_array_pre(      (oop*)start, (int)count, false);
  }
}

// count is number of array elements being written
void BarrierSet::static_write_ref_array_post(HeapWord* start, size_t count) {
  // simply delegate to instance method
  Universe::heap()->barrier_set()->write_ref_array(start, count);
}