Mon, 09 Jun 2008 11:51:19 -0400
6687581: Make CMS work with compressed oops
Summary: Make FreeChunk read markword instead of LSB in _klass pointer to indicate that it's a FreeChunk for compressed oops.
Reviewed-by: ysr, jmasa
duke@435 | 1 | /* |
duke@435 | 2 | * Copyright 2005-2007 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 | inline void oopDesc::update_contents(ParCompactionManager* cm) { |
duke@435 | 26 | // The klass field must be updated before anything else |
duke@435 | 27 | // can be done. |
duke@435 | 28 | DEBUG_ONLY(klassOopDesc* original_klass = klass()); |
duke@435 | 29 | |
duke@435 | 30 | // Can the option to update and/or copy be moved up in the |
duke@435 | 31 | // call chain to avoid calling into here? |
duke@435 | 32 | |
duke@435 | 33 | if (PSParallelCompact::should_update_klass(klass())) { |
duke@435 | 34 | update_header(); |
duke@435 | 35 | assert(klass()->is_klass(), "Not updated correctly"); |
duke@435 | 36 | } else { |
duke@435 | 37 | assert(klass()->is_klass(), "Not updated"); |
duke@435 | 38 | } |
duke@435 | 39 | |
duke@435 | 40 | Klass* new_klass = blueprint(); |
duke@435 | 41 | if (!new_klass->oop_is_typeArray()) { |
duke@435 | 42 | // It might contain oops beyond the header, so take the virtual call. |
duke@435 | 43 | new_klass->oop_update_pointers(cm, this); |
duke@435 | 44 | } |
duke@435 | 45 | // Else skip it. The typeArrayKlass in the header never needs scavenging. |
duke@435 | 46 | } |
duke@435 | 47 | |
duke@435 | 48 | inline void oopDesc::update_contents(ParCompactionManager* cm, |
duke@435 | 49 | HeapWord* begin_limit, |
duke@435 | 50 | HeapWord* end_limit) { |
duke@435 | 51 | // The klass field must be updated before anything else |
duke@435 | 52 | // can be done. |
duke@435 | 53 | debug_only(klassOopDesc* original_klass = klass()); |
duke@435 | 54 | |
duke@435 | 55 | update_contents(cm, klass(), begin_limit, end_limit); |
duke@435 | 56 | } |
duke@435 | 57 | |
duke@435 | 58 | inline void oopDesc::update_contents(ParCompactionManager* cm, |
duke@435 | 59 | klassOop old_klass, |
duke@435 | 60 | HeapWord* begin_limit, |
duke@435 | 61 | HeapWord* end_limit) { |
duke@435 | 62 | |
duke@435 | 63 | klassOop updated_klass = |
duke@435 | 64 | PSParallelCompact::summary_data().calc_new_klass(old_klass); |
duke@435 | 65 | |
duke@435 | 66 | // Needs to be boundary aware for the 64 bit case |
duke@435 | 67 | // update_header(); |
duke@435 | 68 | // The klass has moved. Is the location of the klass |
duke@435 | 69 | // within the limits? |
coleenp@548 | 70 | if ((((HeapWord*)&_metadata._klass) >= begin_limit) && |
coleenp@548 | 71 | (((HeapWord*)&_metadata._klass) < end_limit)) { |
duke@435 | 72 | set_klass(updated_klass); |
duke@435 | 73 | } |
duke@435 | 74 | |
duke@435 | 75 | Klass* klass = updated_klass->klass_part(); |
duke@435 | 76 | if (!klass->oop_is_typeArray()) { |
duke@435 | 77 | // It might contain oops beyond the header, so take the virtual call. |
duke@435 | 78 | klass->oop_update_pointers(cm, this, begin_limit, end_limit); |
duke@435 | 79 | } |
duke@435 | 80 | // Else skip it. The typeArrayKlass in the header never needs scavenging. |
duke@435 | 81 | } |
duke@435 | 82 | |
duke@435 | 83 | inline void oopDesc::follow_contents(ParCompactionManager* cm) { |
duke@435 | 84 | assert (PSParallelCompact::mark_bitmap()->is_marked(this), |
duke@435 | 85 | "should be marked"); |
duke@435 | 86 | blueprint()->oop_follow_contents(cm, this); |
duke@435 | 87 | } |
duke@435 | 88 | |
duke@435 | 89 | // Used by parallel old GC. |
duke@435 | 90 | |
duke@435 | 91 | inline void oopDesc::follow_header(ParCompactionManager* cm) { |
coleenp@548 | 92 | if (UseCompressedOops) { |
coleenp@548 | 93 | PSParallelCompact::mark_and_push(cm, compressed_klass_addr()); |
coleenp@548 | 94 | } else { |
coleenp@548 | 95 | PSParallelCompact::mark_and_push(cm, klass_addr()); |
coleenp@548 | 96 | } |
duke@435 | 97 | } |
duke@435 | 98 | |
duke@435 | 99 | inline oop oopDesc::forward_to_atomic(oop p) { |
duke@435 | 100 | assert(ParNewGeneration::is_legal_forward_ptr(p), |
duke@435 | 101 | "illegal forwarding pointer value."); |
duke@435 | 102 | markOop oldMark = mark(); |
duke@435 | 103 | markOop forwardPtrMark = markOopDesc::encode_pointer_as_mark(p); |
duke@435 | 104 | markOop curMark; |
duke@435 | 105 | |
duke@435 | 106 | assert(forwardPtrMark->decode_pointer() == p, "encoding must be reversable"); |
duke@435 | 107 | assert(sizeof(markOop) == sizeof(intptr_t), "CAS below requires this."); |
duke@435 | 108 | |
duke@435 | 109 | while (!is_forwarded()) { |
duke@435 | 110 | curMark = (markOop)Atomic::cmpxchg_ptr(forwardPtrMark, &_mark, oldMark); |
duke@435 | 111 | if (curMark == oldMark) { |
duke@435 | 112 | assert(is_forwarded(), "the CAS should have succeeded."); |
duke@435 | 113 | return NULL; |
duke@435 | 114 | } |
duke@435 | 115 | oldMark = curMark; |
duke@435 | 116 | } |
duke@435 | 117 | return forwardee(); |
duke@435 | 118 | } |
duke@435 | 119 | |
duke@435 | 120 | inline void oopDesc::update_header() { |
coleenp@548 | 121 | if (UseCompressedOops) { |
coleenp@548 | 122 | PSParallelCompact::adjust_pointer(compressed_klass_addr()); |
coleenp@548 | 123 | } else { |
coleenp@548 | 124 | PSParallelCompact::adjust_pointer(klass_addr()); |
coleenp@548 | 125 | } |
duke@435 | 126 | } |
duke@435 | 127 | |
duke@435 | 128 | inline void oopDesc::update_header(HeapWord* beg_addr, HeapWord* end_addr) { |
coleenp@548 | 129 | if (UseCompressedOops) { |
coleenp@548 | 130 | PSParallelCompact::adjust_pointer(compressed_klass_addr(), |
coleenp@548 | 131 | beg_addr, end_addr); |
coleenp@548 | 132 | } else { |
coleenp@548 | 133 | PSParallelCompact::adjust_pointer(klass_addr(), beg_addr, end_addr); |
coleenp@548 | 134 | } |
duke@435 | 135 | } |