Mercurial > hg > graal-compiler
view src/share/vm/oops/markOop.cpp @ 2149:7e37af9d69ef
7011379: G1: overly long concurrent marking cycles
Summary: This changeset introduces filtering of SATB buffers at the point when they are about to be enqueued. If this filtering clears enough entries on each buffer, the buffer can then be re-used and not enqueued. This cuts down the number of SATB buffers that need to be processed by the concurrent marking threads.
Reviewed-by: johnc, ysr
author | tonyp |
---|---|
date | Wed, 19 Jan 2011 09:35:17 -0500 |
parents | f95d63e2154a |
children | f08d439fab8c |
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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. * */ #include "precompiled.hpp" #include "oops/markOop.hpp" #ifdef TARGET_OS_FAMILY_linux # include "thread_linux.inline.hpp" #endif #ifdef TARGET_OS_FAMILY_solaris # include "thread_solaris.inline.hpp" #endif #ifdef TARGET_OS_FAMILY_windows # include "thread_windows.inline.hpp" #endif void markOopDesc::print_on(outputStream* st) const { if (is_locked()) { st->print("locked(0x%lx)->", value()); markOop(*(markOop*)value())->print_on(st); } else { assert(is_unlocked() || has_bias_pattern(), "just checking"); st->print("mark("); if (has_bias_pattern()) st->print("biased,"); st->print("hash %#lx,", hash()); st->print("age %d)", age()); } } // Give advice about whether the oop that contains this markOop // should be cached or not. bool markOopDesc::should_not_be_cached() const { // the cast is because decode_pointer() isn't marked const if (is_marked() && ((markOopDesc *)this)->decode_pointer() != NULL) { // If the oop containing this markOop is being forwarded, then // we are in the middle of GC and we do not want the containing // oop to be added to a cache. We have no way of knowing whether // the cache has already been visited by the current GC phase so // we don't know whether the forwarded oop will be properly // processed in this phase. If the forwarded oop is not properly // processed, then we'll see strange crashes or asserts during // the next GC run because the markOop will contain an unexpected // value. // // This situation has been seen when we are GC'ing a methodOop // because we use the methodOop while we're GC'ing it. Scary // stuff. Some of the uses the methodOop cause the methodOop to // be added to the OopMapCache in the instanceKlass as a side // effect. This check lets the cache maintainer know when a // cache addition would not be safe. return true; } // caching the containing oop should be just fine return false; }