Mercurial > hg > truffle
view src/os_cpu/windows_x86/vm/bytes_windows_x86.inline.hpp @ 1886:72a161e62cc4
6991377: G1: race between concurrent refinement and humongous object allocation
Summary: There is a race between the concurrent refinement threads and the humongous object allocation that can cause the concurrent refinement threads to corrupt the part of the BOT that it is being initialized by the humongous object allocation operation. The solution is to do the humongous object allocation in careful steps to ensure that the concurrent refinement threads always have a consistent view over the BOT, region contents, and top. The fix includes some very minor tidying up in sparsePRT.
Reviewed-by: jcoomes, johnc, ysr
author | tonyp |
---|---|
date | Sat, 16 Oct 2010 17:12:19 -0400 |
parents | c18cbe5936b8 |
children | f95d63e2154a |
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/* * Copyright (c) 1998, 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. * */ #pragma warning(disable: 4035) // Disable warning 4035: no return value // Efficient swapping of data bytes from Java byte // ordering to native byte ordering and vice versa. inline u2 Bytes::swap_u2(u2 x) { #ifdef AMD64 address p = (address) &x; return ( (u2(p[0]) << 8 ) | ( u2(p[1])) ); #else __asm { mov ax, x xchg al, ah } // no return statement needed, result is already in ax // compiler warning C4035 disabled via warning pragma #endif // AMD64 } inline u4 Bytes::swap_u4(u4 x) { #ifdef AMD64 address p = (address) &x; return ( (u4(p[0]) << 24) | (u4(p[1]) << 16) | (u4(p[2]) << 8) | u4(p[3])) ; #else __asm { mov eax, x bswap eax } // no return statement needed, result is already in eax // compiler warning C4035 disabled via warning pragma #endif // AMD64 } #ifdef AMD64 inline u8 Bytes::swap_u8(u8 x) { address p = (address) &x; return ( (u8(p[0]) << 56) | (u8(p[1]) << 48) | (u8(p[2]) << 40) | (u8(p[3]) << 32) | (u8(p[4]) << 24) | (u8(p[5]) << 16) | (u8(p[6]) << 8) | u8(p[7])) ; } #else // Helper function for swap_u8 inline u8 Bytes::swap_u8_base(u4 x, u4 y) { __asm { mov eax, y mov edx, x bswap eax bswap edx } // no return statement needed, result is already in edx:eax // compiler warning C4035 disabled via warning pragma } inline u8 Bytes::swap_u8(u8 x) { return swap_u8_base(*(u4*)&x, *(((u4*)&x)+1)); } #endif // AMD64 #pragma warning(default: 4035) // Enable warning 4035: no return value