Mon, 30 Jun 2008 17:04:59 -0700
6618726: Introduce -XX:+UnlockExperimentalVMOptions flag
Summary: experimental() flags will protect features of an experimental nature that are not supported in the regular product build. Made UseG1GC an experimental flag.
Reviewed-by: jmasa, kamg, coleenp
duke@435 | 1 | /* |
duke@435 | 2 | * Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
duke@435 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
duke@435 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
duke@435 | 21 | * have any questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
duke@435 | 25 | // An NmethodSweeper is an incremental cleaner for: |
duke@435 | 26 | // - cleanup inline caches |
duke@435 | 27 | // - reclamation of unreferences zombie nmethods |
duke@435 | 28 | // |
duke@435 | 29 | |
duke@435 | 30 | class NMethodSweeper : public AllStatic { |
duke@435 | 31 | static long _traversals; // Stack traversal count |
duke@435 | 32 | static CodeBlob* _current; // Current nmethod |
duke@435 | 33 | static int _seen; // Nof. nmethod we have currently processed in current pass of CodeCache |
duke@435 | 34 | static int _invocations; // No. of invocations left until we are completed with this pass |
duke@435 | 35 | |
duke@435 | 36 | static bool _rescan; // Indicates that we should do a full rescan of the |
duke@435 | 37 | // of the code cache looking for work to do. |
duke@435 | 38 | static int _locked_seen; // Number of locked nmethods encountered during the scan |
duke@435 | 39 | static int _not_entrant_seen_on_stack; // Number of not entrant nmethod were are still on stack |
duke@435 | 40 | |
duke@435 | 41 | |
duke@435 | 42 | static void process_nmethod(nmethod *nm); |
duke@435 | 43 | public: |
duke@435 | 44 | static long traversal_count() { return _traversals; } |
duke@435 | 45 | |
duke@435 | 46 | static void sweep(); // Invoked at the end of each safepoint |
duke@435 | 47 | |
duke@435 | 48 | static void notify(nmethod* nm) { |
duke@435 | 49 | // Perform a full scan of the code cache from the beginning. No |
duke@435 | 50 | // need to synchronize the setting of this flag since it only |
duke@435 | 51 | // changes to false at safepoint so we can never overwrite it with false. |
duke@435 | 52 | _rescan = true; |
duke@435 | 53 | } |
duke@435 | 54 | }; |