Mercurial > hg > truffle
view src/share/vm/gc_implementation/concurrentMarkSweep/cmsPermGen.hpp @ 3293:1f4413413144
7039089: G1: changeset for 7037276 broke heap verification, and related cleanups
Summary: In G1 heap verification, we no longer scan perm to G1-collected heap refs as part of process_strong_roots() but rather in a separate explicit oop iteration over the perm gen. This preserves the original perm card-marks. Added a new assertion in younger_refs_iterate() to catch a simple subcase where the user may have forgotten a prior save_marks() call, as happened in the case of G1's attempt to iterate perm to G1 refs when verifying the heap before exit. The assert was deliberately weakened for ParNew+CMS and will be fixed for that combination in a future CR. Also made some (non-G1) cleanups related to code and comments obsoleted by the migration of Symbols to the native heap.
Reviewed-by: iveresov, jmasa, tonyp
author | ysr |
---|---|
date | Tue, 26 Apr 2011 21:17:24 -0700 |
parents | f95d63e2154a |
children | 9f059abe8cf2 |
line wrap: on
line source
/* * Copyright (c) 2007, 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 SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_CMSPERMGEN_HPP #define SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_CMSPERMGEN_HPP #include "gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.hpp" #include "memory/permGen.hpp" class CardTableRS; // fwd decl class ConcurrentMarkSweepGeneration; // A PermGen implemented with a CMS space, collected by a CMS collector. class CMSPermGen: public PermGen { friend class VMStructs; protected: // The "generation" view. ConcurrentMarkSweepGeneration* _gen; // Override default implementation from PermGen virtual HeapWord* request_expand_and_allocate(Generation* gen, size_t size, GCCause::Cause prev_cause); public: CMSPermGen(ReservedSpace rs, size_t initial_byte_size, CardTableRS* ct, FreeBlockDictionary::DictionaryChoice); HeapWord* mem_allocate(size_t size); void compute_new_size(); Generation* as_gen() const { return _gen; } }; // This is the "generation" view of a CMSPermGen. class CMSPermGenGen: public ConcurrentMarkSweepGeneration { // Abstractly, this is a subtype that gets access to protected fields. friend class CMSPermGen; public: CMSPermGenGen(ReservedSpace rs, size_t initial_byte_size, int level, CardTableRS* ct): // See comments in the constructor for CompactibleFreeListSpace // regarding not using adaptive free lists for a perm gen. ConcurrentMarkSweepGeneration(rs, initial_byte_size, // MinPermHeapExapnsion level, ct, false /* use adaptive freelists */, (FreeBlockDictionary::DictionaryChoice)CMSDictionaryChoice) {} void initialize_performance_counters(); const char* name() const { return "concurrent-mark-sweep perm gen"; } const char* short_name() const { return "CMS Perm"; } bool must_be_youngest() const { return false; } bool must_be_oldest() const { return false; } }; #endif // SHARE_VM_GC_IMPLEMENTATION_CONCURRENTMARKSWEEP_CMSPERMGEN_HPP