Mercurial > hg > truffle
view src/share/vm/memory/padded.inline.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 | 9766f73e770d |
children | d7070f371770 |
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/* * Copyright (c) 2013, 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. * */ #include "memory/allocation.inline.hpp" #include "memory/padded.hpp" #include "utilities/debug.hpp" #include "utilities/globalDefinitions.hpp" // Creates an aligned padded array. // The memory can't be deleted since the raw memory chunk is not returned. template <class T, MEMFLAGS flags, size_t alignment> PaddedEnd<T>* PaddedArray<T, flags, alignment>::create_unfreeable(uint length) { // Check that the PaddedEnd class works as intended. STATIC_ASSERT(is_size_aligned_(sizeof(PaddedEnd<T>), alignment)); // Allocate a chunk of memory large enough to allow for some alignment. void* chunk = AllocateHeap(length * sizeof(PaddedEnd<T, alignment>) + alignment, flags); // Make the initial alignment. PaddedEnd<T>* aligned_padded_array = (PaddedEnd<T>*)align_pointer_up(chunk, alignment); // Call the default constructor for each element. for (uint i = 0; i < length; i++) { ::new (&aligned_padded_array[i]) T(); } return aligned_padded_array; }