Mercurial > hg > truffle
view src/cpu/x86/vm/icache_x86.hpp @ 20504:6948da6d7c13
8052172: Evacuation failure handling in G1 does not evacuate all objects if -XX:-G1DeferredRSUpdate is set
Summary: Remove -XX:-G1DeferredRSUpdate functionality as it is racy. During evacuation failure handling, threads where evacuation failure handling occurred may try to add remembered sets to regions which remembered sets are currently being scanned. The iterator to handle the remembered set scan does not support addition of entries during scan and so may skip valid references.
Reviewed-by: iveresov, brutisso, mgerdin
author | tschatzl |
---|---|
date | Tue, 30 Sep 2014 09:44:36 +0200 |
parents | 6ae7a1561b53 |
children |
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/* * Copyright (c) 1997, 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 CPU_X86_VM_ICACHE_X86_HPP #define CPU_X86_VM_ICACHE_X86_HPP // Interface for updating the instruction cache. Whenever the VM modifies // code, part of the processor instruction cache potentially has to be flushed. // On the x86, this is a no-op -- the I-cache is guaranteed to be consistent // after the next jump, and the VM never modifies instructions directly ahead // of the instruction fetch path. // [phh] It's not clear that the above comment is correct, because on an MP // system where the dcaches are not snooped, only the thread doing the invalidate // will see the update. Even in the snooped case, a memory fence would be // necessary if stores weren't ordered. Fortunately, they are on all known // x86 implementations. class ICache : public AbstractICache { public: #ifdef AMD64 enum { stub_size = 64, // Size of the icache flush stub in bytes line_size = 64, // Icache line size in bytes log2_line_size = 6 // log2(line_size) }; // Use default implementation #else enum { stub_size = 16, // Size of the icache flush stub in bytes line_size = BytesPerWord, // conservative log2_line_size = LogBytesPerWord // log2(line_size) }; #endif // AMD64 }; #endif // CPU_X86_VM_ICACHE_X86_HPP