Mercurial > hg > truffle
view src/share/vm/memory/watermark.hpp @ 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 | f95d63e2154a |
children |
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/* * Copyright (c) 2000, 2010, 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 * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_VM_MEMORY_WATERMARK_HPP #define SHARE_VM_MEMORY_WATERMARK_HPP #include "memory/allocation.hpp" #include "utilities/globalDefinitions.hpp" // A water mark points into a space and is used during GC to keep track of // progress. class Space; class WaterMark VALUE_OBJ_CLASS_SPEC { friend class VMStructs; private: HeapWord* _point; Space* _space; public: // Accessors Space* space() const { return _space; } void set_space(Space* s) { _space = s; } HeapWord* point() const { return _point; } void set_point(HeapWord* p) { _point = p; } // Constructors WaterMark(Space* s, HeapWord* p) : _space(s), _point(p) {}; WaterMark() : _space(NULL), _point(NULL) {}; }; inline bool operator==(const WaterMark& x, const WaterMark& y) { return (x.point() == y.point()) && (x.space() == y.space()); } inline bool operator!=(const WaterMark& x, const WaterMark& y) { return !(x == y); } #endif // SHARE_VM_MEMORY_WATERMARK_HPP