Sat, 01 Sep 2012 13:25:18 -0400
6964458: Reimplement class meta-data storage to use native memory
Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>
1 /*
2 * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
25 #ifndef SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_CARDTABLEEXTENSION_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_CARDTABLEEXTENSION_HPP
28 #include "memory/cardTableModRefBS.hpp"
30 class MutableSpace;
31 class ObjectStartArray;
32 class PSPromotionManager;
33 class GCTaskQueue;
35 class CardTableExtension : public CardTableModRefBS {
36 private:
37 // Support methods for resizing the card table.
38 // resize_commit_uncommit() returns true if the pages were committed or
39 // uncommitted
40 bool resize_commit_uncommit(int changed_region, MemRegion new_region);
41 void resize_update_card_table_entries(int changed_region,
42 MemRegion new_region);
43 void resize_update_committed_table(int changed_region, MemRegion new_region);
44 void resize_update_covered_table(int changed_region, MemRegion new_region);
46 protected:
48 static void verify_all_young_refs_precise_helper(MemRegion mr);
50 public:
51 enum ExtendedCardValue {
52 youngergen_card = CardTableModRefBS::CT_MR_BS_last_reserved + 1,
53 verify_card = CardTableModRefBS::CT_MR_BS_last_reserved + 5
54 };
56 CardTableExtension(MemRegion whole_heap, int max_covered_regions) :
57 CardTableModRefBS(whole_heap, max_covered_regions) { }
59 // Too risky for the 4/10/02 putback
60 // BarrierSet::Name kind() { return BarrierSet::CardTableExtension; }
62 // Scavenge support
63 void scavenge_contents(ObjectStartArray* start_array,
64 MutableSpace* sp,
65 HeapWord* space_top,
66 PSPromotionManager* pm);
68 void scavenge_contents_parallel(ObjectStartArray* start_array,
69 MutableSpace* sp,
70 HeapWord* space_top,
71 PSPromotionManager* pm,
72 uint stripe_number,
73 uint stripe_total);
75 // Verification
76 static void verify_all_young_refs_imprecise();
77 static void verify_all_young_refs_precise();
79 bool addr_is_marked_imprecise(void *addr);
80 bool addr_is_marked_precise(void *addr);
82 void set_card_newgen(void* addr) { jbyte* p = byte_for(addr); *p = verify_card; }
84 // Testers for entries
85 static bool card_is_dirty(int value) { return value == dirty_card; }
86 static bool card_is_newgen(int value) { return value == youngergen_card; }
87 static bool card_is_clean(int value) { return value == clean_card; }
88 static bool card_is_verify(int value) { return value == verify_card; }
90 // Card marking
91 void inline_write_ref_field_gc(void* field, oop new_val) {
92 jbyte* byte = byte_for(field);
93 *byte = youngergen_card;
94 }
96 // Adaptive size policy support
97 // Allows adjustment of the base and size of the covered regions
98 void resize_covered_region(MemRegion new_region);
99 // Finds the covered region to resize based on the start address
100 // of the covered regions.
101 void resize_covered_region_by_start(MemRegion new_region);
102 // Finds the covered region to resize based on the end address
103 // of the covered regions.
104 void resize_covered_region_by_end(int changed_region, MemRegion new_region);
105 // Finds the lowest start address of a covered region that is
106 // previous (i.e., lower index) to the covered region with index "ind".
107 HeapWord* lowest_prev_committed_start(int ind) const;
109 #ifdef ASSERT
111 bool is_valid_card_address(jbyte* addr) {
112 return (addr >= _byte_map) && (addr < _byte_map + _byte_map_size);
113 }
115 #endif // ASSERT
116 };
118 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_CARDTABLEEXTENSION_HPP