Mercurial > hg > graal-jvmci-8
view test/gc/TestG1ZeroPGCTJcmdThreadPrint.java @ 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 | b9c5e46bf915 |
children |
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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. */ /* @test TestG1ZeroPGCTJcmdThreadPrint * @key gc * @bug 8005875 * @summary Use jcmd to generate a thread dump of a Java program being run with PGCT=0 to verify 8005875 * @library /testlibrary * @run main/othervm -XX:+UseG1GC -XX:ParallelGCThreads=0 -XX:+IgnoreUnrecognizedVMOptions TestG1ZeroPGCTJcmdThreadPrint */ import com.oracle.java.testlibrary.*; public class TestG1ZeroPGCTJcmdThreadPrint { public static void main(String args[]) throws Exception { // Grab the pid from the current java process String pid = Integer.toString(ProcessTools.getProcessId()); // Create a ProcessBuilder ProcessBuilder pb = new ProcessBuilder(); // Run jcmd <pid> Thread.print pb.command(JDKToolFinder.getJDKTool("jcmd"), pid, "Thread.print"); OutputAnalyzer output = new OutputAnalyzer(pb.start()); // There shouldn't be a work gang for concurrent marking. output.shouldNotContain("G1 Parallel Marking Threads"); // Make sure we didn't crash output.shouldHaveExitValue(0); } }