1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/memory/cardTableRS.hpp Sat Dec 01 00:00:00 2007 +0000
1.3 @@ -0,0 +1,156 @@
1.4 +/*
1.5 + * Copyright 2001-2006 Sun Microsystems, Inc. All Rights Reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
1.23 + * CA 95054 USA or visit www.sun.com if you need additional information or
1.24 + * have any questions.
1.25 + *
1.26 + */
1.27 +
1.28 +class Space;
1.29 +class OopsInGenClosure;
1.30 +class DirtyCardToOopClosure;
1.31 +
1.32 +// This kind of "GenRemSet" uses a card table both as shared data structure
1.33 +// for a mod ref barrier set and for the rem set information.
1.34 +
1.35 +class CardTableRS: public GenRemSet {
1.36 + friend class VMStructs;
1.37 + // Below are private classes used in impl.
1.38 + friend class VerifyCTSpaceClosure;
1.39 + friend class ClearNoncleanCardWrapper;
1.40 +
1.41 + static jbyte clean_card_val() {
1.42 + return CardTableModRefBS::clean_card;
1.43 + }
1.44 +
1.45 + static bool
1.46 + card_is_dirty_wrt_gen_iter(jbyte cv) {
1.47 + return CardTableModRefBS::card_is_dirty_wrt_gen_iter(cv);
1.48 + }
1.49 +
1.50 + CardTableModRefBSForCTRS _ct_bs;
1.51 +
1.52 + virtual void younger_refs_in_space_iterate(Space* sp, OopsInGenClosure* cl);
1.53 +
1.54 + void verify_space(Space* s, HeapWord* gen_start);
1.55 +
1.56 + enum ExtendedCardValue {
1.57 + youngergen_card = CardTableModRefBS::CT_MR_BS_last_reserved + 1,
1.58 + // These are for parallel collection.
1.59 + // There are three P (parallel) youngergen card values. In general, this
1.60 + // needs to be more than the number of generations (including the perm
1.61 + // gen) that might have younger_refs_do invoked on them separately. So
1.62 + // if we add more gens, we have to add more values.
1.63 + youngergenP1_card = CardTableModRefBS::CT_MR_BS_last_reserved + 2,
1.64 + youngergenP2_card = CardTableModRefBS::CT_MR_BS_last_reserved + 3,
1.65 + youngergenP3_card = CardTableModRefBS::CT_MR_BS_last_reserved + 4,
1.66 + cur_youngergen_and_prev_nonclean_card =
1.67 + CardTableModRefBS::CT_MR_BS_last_reserved + 5
1.68 + };
1.69 +
1.70 + // An array that contains, for each generation, the card table value last
1.71 + // used as the current value for a younger_refs_do iteration of that
1.72 + // portion of the table. (The perm gen is index 0; other gens are at
1.73 + // their level plus 1. They youngest gen is in the table, but will
1.74 + // always have the value "clean_card".)
1.75 + jbyte* _last_cur_val_in_gen;
1.76 +
1.77 + jbyte _cur_youngergen_card_val;
1.78 +
1.79 + jbyte cur_youngergen_card_val() {
1.80 + return _cur_youngergen_card_val;
1.81 + }
1.82 + void set_cur_youngergen_card_val(jbyte v) {
1.83 + _cur_youngergen_card_val = v;
1.84 + }
1.85 + bool is_prev_youngergen_card_val(jbyte v) {
1.86 + return
1.87 + youngergen_card <= v &&
1.88 + v < cur_youngergen_and_prev_nonclean_card &&
1.89 + v != _cur_youngergen_card_val;
1.90 + }
1.91 + // Return a youngergen_card_value that is not currently in use.
1.92 + jbyte find_unused_youngergenP_card_value();
1.93 +
1.94 +public:
1.95 + CardTableRS(MemRegion whole_heap, int max_covered_regions);
1.96 +
1.97 + // *** GenRemSet functions.
1.98 + GenRemSet::Name rs_kind() { return GenRemSet::CardTable; }
1.99 +
1.100 + CardTableRS* as_CardTableRS() { return this; }
1.101 +
1.102 + CardTableModRefBS* ct_bs() { return &_ct_bs; }
1.103 +
1.104 + // Override.
1.105 + void prepare_for_younger_refs_iterate(bool parallel);
1.106 +
1.107 + // Card table entries are cleared before application; "blk" is
1.108 + // responsible for dirtying if the oop is still older-to-younger after
1.109 + // closure application.
1.110 + void younger_refs_iterate(Generation* g, OopsInGenClosure* blk);
1.111 +
1.112 + void inline_write_ref_field_gc(oop* field, oop new_val) {
1.113 + jbyte* byte = _ct_bs.byte_for(field);
1.114 + *byte = youngergen_card;
1.115 + }
1.116 + void write_ref_field_gc_work(oop* field, oop new_val) {
1.117 + inline_write_ref_field_gc(field, new_val);
1.118 + }
1.119 +
1.120 + // Override. Might want to devirtualize this in the same fashion as
1.121 + // above. Ensures that the value of the card for field says that it's
1.122 + // a younger card in the current collection.
1.123 + virtual void write_ref_field_gc_par(oop* field, oop new_val);
1.124 +
1.125 + void resize_covered_region(MemRegion new_region);
1.126 +
1.127 + bool is_aligned(HeapWord* addr) {
1.128 + return _ct_bs.is_card_aligned(addr);
1.129 + }
1.130 +
1.131 + void verify();
1.132 + void verify_empty(MemRegion mr);
1.133 +
1.134 + void clear(MemRegion mr) { _ct_bs.clear(mr); }
1.135 + void clear_into_younger(Generation* gen, bool clear_perm);
1.136 +
1.137 + void invalidate(MemRegion mr) { _ct_bs.invalidate(mr); }
1.138 + void invalidate_or_clear(Generation* gen, bool younger, bool perm);
1.139 +
1.140 + static uintx ct_max_alignment_constraint() {
1.141 + return CardTableModRefBS::ct_max_alignment_constraint();
1.142 + }
1.143 +
1.144 + jbyte* byte_for(void* p) { return _ct_bs.byte_for(p); }
1.145 + jbyte* byte_after(void* p) { return _ct_bs.byte_after(p); }
1.146 + HeapWord* addr_for(jbyte* p) { return _ct_bs.addr_for(p); }
1.147 +
1.148 + bool is_prev_nonclean_card_val(jbyte v) {
1.149 + return
1.150 + youngergen_card <= v &&
1.151 + v <= cur_youngergen_and_prev_nonclean_card &&
1.152 + v != _cur_youngergen_card_val;
1.153 + }
1.154 +
1.155 + static bool youngergen_may_have_been_dirty(jbyte cv) {
1.156 + return cv == CardTableRS::cur_youngergen_and_prev_nonclean_card;
1.157 + }
1.158 +
1.159 +};
