src/share/vm/gc_implementation/g1/concurrentG1Refine.hpp

Fri, 02 Oct 2009 16:12:07 -0400

author
tonyp
date
Fri, 02 Oct 2009 16:12:07 -0400
changeset 1454
035d2e036a9b
parent 1325
6cb8e9df7174
child 1546
44f61c24ddab
permissions
-rw-r--r--

6885041: G1: inconsistent thread dump
Summary: When G1 is enabled, thread dumps are inconsistent as the info for some of the G1 threads is not formatted properly.
Reviewed-by: ysr, johnc

ysr@777 1 /*
xdono@1014 2 * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved.
ysr@777 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@777 4 *
ysr@777 5 * This code is free software; you can redistribute it and/or modify it
ysr@777 6 * under the terms of the GNU General Public License version 2 only, as
ysr@777 7 * published by the Free Software Foundation.
ysr@777 8 *
ysr@777 9 * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@777 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@777 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
ysr@777 12 * version 2 for more details (a copy is included in the LICENSE file that
ysr@777 13 * accompanied this code).
ysr@777 14 *
ysr@777 15 * You should have received a copy of the GNU General Public License version
ysr@777 16 * 2 along with this work; if not, write to the Free Software Foundation,
ysr@777 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@777 18 *
ysr@777 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
ysr@777 20 * CA 95054 USA or visit www.sun.com if you need additional information or
ysr@777 21 * have any questions.
ysr@777 22 *
ysr@777 23 */
ysr@777 24
ysr@777 25 // Forward decl
ysr@777 26 class ConcurrentG1RefineThread;
ysr@777 27 class G1RemSet;
ysr@777 28
apetrusenko@984 29 class ConcurrentG1Refine: public CHeapObj {
iveresov@1229 30 ConcurrentG1RefineThread** _threads;
iveresov@1229 31 int _n_threads;
johnc@1325 32
ysr@777 33 // The cache for card refinement.
johnc@1325 34 bool _use_cache;
johnc@1325 35 bool _def_use_cache;
ysr@777 36
johnc@1325 37 size_t _n_periods; // Used as clearing epoch
johnc@1325 38
johnc@1325 39 // An evicting cache of the number of times each card
johnc@1325 40 // is accessed. Reduces, but does not eliminate, the amount
johnc@1325 41 // of duplicated processing of dirty cards.
johnc@1325 42
johnc@1325 43 enum SomePrivateConstants {
johnc@1325 44 epoch_bits = 32,
johnc@1325 45 card_num_shift = epoch_bits,
johnc@1325 46 epoch_mask = AllBits,
johnc@1325 47 card_num_mask = AllBits,
johnc@1325 48
johnc@1325 49 // The initial cache size is approximately this fraction
johnc@1325 50 // of a maximal cache (i.e. the size needed for all cards
johnc@1325 51 // in the heap)
johnc@1325 52 InitialCacheFraction = 512
johnc@1325 53 };
johnc@1325 54
johnc@1325 55 const static julong card_num_mask_in_place =
johnc@1325 56 (julong) card_num_mask << card_num_shift;
johnc@1325 57
johnc@1325 58 typedef struct {
johnc@1325 59 julong _value; // | card_num | epoch |
johnc@1325 60 } CardEpochCacheEntry;
johnc@1325 61
johnc@1325 62 julong make_epoch_entry(unsigned int card_num, unsigned int epoch) {
johnc@1325 63 assert(0 <= card_num && card_num < _max_n_card_counts, "Bounds");
johnc@1325 64 assert(0 <= epoch && epoch <= _n_periods, "must be");
johnc@1325 65
johnc@1325 66 return ((julong) card_num << card_num_shift) | epoch;
johnc@1325 67 }
johnc@1325 68
johnc@1325 69 unsigned int extract_epoch(julong v) {
johnc@1325 70 return (v & epoch_mask);
johnc@1325 71 }
johnc@1325 72
johnc@1325 73 unsigned int extract_card_num(julong v) {
johnc@1325 74 return (v & card_num_mask_in_place) >> card_num_shift;
johnc@1325 75 }
johnc@1325 76
johnc@1325 77 typedef struct {
johnc@1325 78 unsigned char _count;
johnc@1325 79 unsigned char _evict_count;
johnc@1325 80 } CardCountCacheEntry;
johnc@1325 81
johnc@1325 82 CardCountCacheEntry* _card_counts;
johnc@1325 83 CardEpochCacheEntry* _card_epochs;
johnc@1325 84
johnc@1325 85 // The current number of buckets in the card count cache
johnc@1325 86 unsigned _n_card_counts;
johnc@1325 87
johnc@1325 88 // The max number of buckets required for the number of
johnc@1325 89 // cards for the entire reserved heap
johnc@1325 90 unsigned _max_n_card_counts;
johnc@1325 91
johnc@1325 92 // Possible sizes of the cache: odd primes that roughly double in size.
johnc@1325 93 // (See jvmtiTagMap.cpp).
johnc@1325 94 static int _cc_cache_sizes[];
johnc@1325 95
johnc@1325 96 // The index in _cc_cache_sizes corresponding to the size of
johnc@1325 97 // _card_counts.
johnc@1325 98 int _cache_size_index;
johnc@1325 99
johnc@1325 100 bool _expand_card_counts;
johnc@1325 101
johnc@1325 102 const jbyte* _ct_bot;
johnc@1324 103
johnc@1324 104 jbyte** _hot_cache;
johnc@1324 105 int _hot_cache_size;
johnc@1324 106 int _n_hot;
johnc@1324 107 int _hot_cache_idx;
johnc@1324 108
johnc@1324 109 int _hot_cache_par_chunk_size;
johnc@1324 110 volatile int _hot_cache_par_claimed_idx;
ysr@777 111
johnc@1325 112 // Needed to workaround 6817995
johnc@1325 113 CardTableModRefBS* _ct_bs;
johnc@1325 114 G1CollectedHeap* _g1h;
johnc@1325 115
johnc@1325 116 // Expands the array that holds the card counts to the next size up
johnc@1325 117 void expand_card_count_cache();
johnc@1325 118
johnc@1325 119 // hash a given key (index of card_ptr) with the specified size
johnc@1325 120 static unsigned int hash(size_t key, int size) {
johnc@1325 121 return (unsigned int) key % size;
johnc@1325 122 }
johnc@1325 123
johnc@1325 124 // hash a given key (index of card_ptr)
johnc@1325 125 unsigned int hash(size_t key) {
johnc@1325 126 return hash(key, _n_card_counts);
johnc@1325 127 }
johnc@1325 128
johnc@1325 129 unsigned ptr_2_card_num(jbyte* card_ptr) {
johnc@1325 130 return (unsigned) (card_ptr - _ct_bot);
johnc@1325 131 }
johnc@1325 132
johnc@1325 133 jbyte* card_num_2_ptr(unsigned card_num) {
johnc@1325 134 return (jbyte*) (_ct_bot + card_num);
johnc@1325 135 }
johnc@1325 136
ysr@777 137 // Returns the count of this card after incrementing it.
johnc@1325 138 jbyte* add_card_count(jbyte* card_ptr, int* count, bool* defer);
ysr@777 139
johnc@1325 140 // Returns true if this card is in a young region
johnc@1325 141 bool is_young_card(jbyte* card_ptr);
johnc@1325 142
ysr@777 143 public:
ysr@777 144 ConcurrentG1Refine();
ysr@777 145 ~ConcurrentG1Refine();
ysr@777 146
ysr@777 147 void init(); // Accomplish some initialization that has to wait.
iveresov@1229 148 void stop();
ysr@777 149
iveresov@1229 150 // Iterate over the conc refine threads
iveresov@1229 151 void threads_do(ThreadClosure *tc);
ysr@777 152
ysr@777 153 // If this is the first entry for the slot, writes into the cache and
ysr@777 154 // returns NULL. If it causes an eviction, returns the evicted pointer.
ysr@777 155 // Otherwise, its a cache hit, and returns NULL.
johnc@1325 156 jbyte* cache_insert(jbyte* card_ptr, bool* defer);
ysr@777 157
ysr@777 158 // Process the cached entries.
ysr@777 159 void clean_up_cache(int worker_i, G1RemSet* g1rs);
ysr@777 160
johnc@1324 161 // Set up for parallel processing of the cards in the hot cache
johnc@1324 162 void clear_hot_cache_claimed_index() {
johnc@1324 163 _hot_cache_par_claimed_idx = 0;
johnc@1324 164 }
johnc@1324 165
ysr@777 166 // Discard entries in the hot cache.
ysr@777 167 void clear_hot_cache() {
ysr@777 168 _hot_cache_idx = 0; _n_hot = 0;
ysr@777 169 }
ysr@777 170
ysr@777 171 bool hot_cache_is_empty() { return _n_hot == 0; }
ysr@777 172
ysr@777 173 bool use_cache() { return _use_cache; }
ysr@777 174 void set_use_cache(bool b) {
ysr@777 175 if (b) _use_cache = _def_use_cache;
ysr@777 176 else _use_cache = false;
ysr@777 177 }
ysr@777 178
ysr@777 179 void clear_and_record_card_counts();
iveresov@1230 180
iveresov@1230 181 static size_t thread_num();
tonyp@1454 182
tonyp@1454 183 void print_worker_threads_on(outputStream* st) const;
ysr@777 184 };

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