Mercurial > hg > truffle
view src/share/vm/memory/iterator.cpp @ 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 | 5888334c9c24 |
children | de6a9e811145 |
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/* * Copyright (c) 1997, 2012, 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 "memory/iterator.hpp" #include "oops/oop.inline.hpp" void KlassToOopClosure::do_klass(Klass* k) { k->oops_do(_oop_closure); } void CLDToOopClosure::do_cld(ClassLoaderData* cld) { cld->oops_do(_oop_closure, &_klass_closure, _must_claim_cld); } void ObjectToOopClosure::do_object(oop obj) { obj->oop_iterate(_cl); } void VoidClosure::do_void() { ShouldNotCallThis(); } MarkingCodeBlobClosure::MarkScope::MarkScope(bool activate) : _active(activate) { if (_active) nmethod::oops_do_marking_prologue(); } MarkingCodeBlobClosure::MarkScope::~MarkScope() { if (_active) nmethod::oops_do_marking_epilogue(); } void MarkingCodeBlobClosure::do_code_blob(CodeBlob* cb) { nmethod* nm = cb->as_nmethod_or_null(); if (nm == NULL) return; if (!nm->test_set_oops_do_mark()) { NOT_PRODUCT(if (TraceScavenge) nm->print_on(tty, "oops_do, 1st visit\n")); do_newly_marked_nmethod(nm); } else { NOT_PRODUCT(if (TraceScavenge) nm->print_on(tty, "oops_do, skipped on 2nd visit\n")); } } void CodeBlobToOopClosure::do_newly_marked_nmethod(nmethod* nm) { nm->oops_do(_cl, /*allow_zombie=*/ false); } void CodeBlobToOopClosure::do_code_blob(CodeBlob* cb) { if (!_do_marking) { nmethod* nm = cb->as_nmethod_or_null(); NOT_PRODUCT(if (TraceScavenge && Verbose && nm != NULL) nm->print_on(tty, "oops_do, unmarked visit\n")); // This assert won't work, since there are lots of mini-passes // (mostly in debug mode) that co-exist with marking phases. //assert(!(cb->is_nmethod() && ((nmethod*)cb)->test_oops_do_mark()), "found marked nmethod during mark-free phase"); if (nm != NULL) { nm->oops_do(_cl); } } else { MarkingCodeBlobClosure::do_code_blob(cb); } }