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.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1CARDCOUNTS_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1CARDCOUNTS_HPP
27
28 #include "memory/allocation.hpp"
29 #include "runtime/virtualspace.hpp"
30 #include "utilities/globalDefinitions.hpp"
31
32 class CardTableModRefBS;
33 class G1CollectedHeap;
34 class HeapRegion;
35
36 // Table to track the number of times a card has been refined. Once
37 // a card has been refined a certain number of times, it is
38 // considered 'hot' and its refinement is delayed by inserting the
39 // card into the hot card cache. The card will then be refined when
40 // it is evicted from the hot card cache, or when the hot card cache
41 // is 'drained' during the next evacuation pause.
42
43 class G1CardCounts: public CHeapObj<mtGC> {
44 G1CollectedHeap* _g1h;
45
46 // The table of counts
47 jubyte* _card_counts;
48
49 // Max capacity of the reserved space for the counts table
50 size_t _reserved_max_card_num;
51
52 // Max capacity of the committed space for the counts table
53 size_t _committed_max_card_num;
54
55 // Size of committed space for the counts table
56 size_t _committed_size;
57
58 // CardTable bottom.
59 const jbyte* _ct_bot;
60
61 // Barrier set
62 CardTableModRefBS* _ct_bs;
63
64 // The virtual memory backing the counts table
65 VirtualSpace _card_counts_storage;
66
67 // Returns true if the card counts table has been reserved.
68 bool has_reserved_count_table() { return _card_counts != NULL; }
69
70 // Returns true if the card counts table has been reserved and committed.
71 bool has_count_table() {
72 return has_reserved_count_table() && _committed_max_card_num > 0;
73 }
74
75 size_t ptr_2_card_num(const jbyte* card_ptr) {
76 assert(card_ptr >= _ct_bot,
77 err_msg("Invalid card pointer: "
78 "card_ptr: " PTR_FORMAT ", "
79 "_ct_bot: " PTR_FORMAT,
80 p2i(card_ptr), p2i(_ct_bot)));
81 size_t card_num = pointer_delta(card_ptr, _ct_bot, sizeof(jbyte));
82 assert(card_num >= 0 && card_num < _committed_max_card_num,
83 err_msg("card pointer out of range: " PTR_FORMAT, p2i(card_ptr)));
84 return card_num;
85 }
86
87 jbyte* card_num_2_ptr(size_t card_num) {
88 assert(card_num >= 0 && card_num < _committed_max_card_num,
89 err_msg("card num out of range: "SIZE_FORMAT, card_num));
90 return (jbyte*) (_ct_bot + card_num);
91 }
92
93 // Helper routine.
94 // Returns the number of cards that can be counted by the given committed
95 // table size, with a maximum of the number of cards spanned by the max
96 // capacity of the heap.
97 size_t committed_to_card_num(size_t committed_size) {
98 return MIN2(_reserved_max_card_num, committed_size / sizeof(jbyte));
99 }
100
101 // Clear the counts table for the given (exclusive) index range.
102 void clear_range(size_t from_card_num, size_t to_card_num);
103
104 public:
105 G1CardCounts(G1CollectedHeap* g1h);
106 ~G1CardCounts();
107
108 void initialize();
109
110 // Resize the committed space for the card counts table in
111 // response to a resize of the committed space for the heap.
112 void resize(size_t heap_capacity);
113
114 // Increments the refinement count for the given card.
115 // Returns the pre-increment count value.
116 uint add_card_count(jbyte* card_ptr);
117
118 // Returns true if the given count is high enough to be considered
119 // 'hot'; false otherwise.
120 bool is_hot(uint count);
121
122 // Clears the card counts for the cards spanned by the region
123 void clear_region(HeapRegion* hr);
124
125 // Clear the entire card counts table during GC.
126 // Updates the policy stats with the duration.
127 void clear_all();
128 };
129
130 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1CARDCOUNTS_HPP
|
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.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1CARDCOUNTS_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1CARDCOUNTS_HPP
27
28 #include "gc_implementation/g1/g1RegionToSpaceMapper.hpp"
29 #include "memory/allocation.hpp"
30 #include "runtime/virtualspace.hpp"
31 #include "utilities/globalDefinitions.hpp"
32
33 class CardTableModRefBS;
34 class G1CardCounts;
35 class G1CollectedHeap;
36 class G1RegionToSpaceMapper;
37 class HeapRegion;
38
39 class G1CardCountsMappingChangedListener : public G1MappingChangedListener {
40 private:
41 G1CardCounts* _counts;
42 public:
43 void set_cardcounts(G1CardCounts* counts) { _counts = counts; }
44
45 virtual void on_commit(uint start_idx, size_t num_regions);
46 };
47
48 // Table to track the number of times a card has been refined. Once
49 // a card has been refined a certain number of times, it is
50 // considered 'hot' and its refinement is delayed by inserting the
51 // card into the hot card cache. The card will then be refined when
52 // it is evicted from the hot card cache, or when the hot card cache
53 // is 'drained' during the next evacuation pause.
54
55 class G1CardCounts: public CHeapObj<mtGC> {
56 G1CardCountsMappingChangedListener _listener;
57
58 G1CollectedHeap* _g1h;
59
60 // The table of counts
61 jubyte* _card_counts;
62
63 // Max capacity of the reserved space for the counts table
64 size_t _reserved_max_card_num;
65
66 // CardTable bottom.
67 const jbyte* _ct_bot;
68
69 // Barrier set
70 CardTableModRefBS* _ct_bs;
71
72 // Returns true if the card counts table has been reserved.
73 bool has_reserved_count_table() { return _card_counts != NULL; }
74
75 // Returns true if the card counts table has been reserved and committed.
76 bool has_count_table() {
77 return has_reserved_count_table();
78 }
79
80 size_t ptr_2_card_num(const jbyte* card_ptr) {
81 assert(card_ptr >= _ct_bot,
82 err_msg("Invalid card pointer: "
83 "card_ptr: " PTR_FORMAT ", "
84 "_ct_bot: " PTR_FORMAT,
85 p2i(card_ptr), p2i(_ct_bot)));
86 size_t card_num = pointer_delta(card_ptr, _ct_bot, sizeof(jbyte));
87 assert(card_num >= 0 && card_num < _reserved_max_card_num,
88 err_msg("card pointer out of range: " PTR_FORMAT, p2i(card_ptr)));
89 return card_num;
90 }
91
92 jbyte* card_num_2_ptr(size_t card_num) {
93 assert(card_num >= 0 && card_num < _reserved_max_card_num,
94 err_msg("card num out of range: "SIZE_FORMAT, card_num));
95 return (jbyte*) (_ct_bot + card_num);
96 }
97
98 // Clear the counts table for the given (exclusive) index range.
99 void clear_range(size_t from_card_num, size_t to_card_num);
100
101 public:
102 G1CardCounts(G1CollectedHeap* g1h);
103
104 void initialize(G1RegionToSpaceMapper* mapper);
105
106 // Increments the refinement count for the given card.
107 // Returns the pre-increment count value.
108 uint add_card_count(jbyte* card_ptr);
109
110 // Returns true if the given count is high enough to be considered
111 // 'hot'; false otherwise.
112 bool is_hot(uint count);
113
114 // Clears the card counts for the cards spanned by the region
115 void clear_region(HeapRegion* hr);
116
117 // Clears the card counts for the cards spanned by the MemRegion
118 void clear_range(MemRegion mr);
119
120 // Clear the entire card counts table during GC.
121 void clear_all();
122 };
123
124 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1CARDCOUNTS_HPP
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