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_GC_SHARED_PRESERVEDMARKS_HPP
26 #define SHARE_GC_SHARED_PRESERVEDMARKS_HPP
27
28 #include "memory/allocation.hpp"
29 #include "memory/padded.hpp"
30 #include "oops/oop.hpp"
31 #include "utilities/stack.hpp"
32
33 class WorkerTask;
34 class PreservedMarksSet;
35 class WorkerThreads;
36
37 class PreservedMarks {
38 private:
39 class OopAndMarkWord {
40 private:
41 oop _o;
42 markWord _m;
43
44 public:
45 OopAndMarkWord(oop obj, markWord m) : _o(obj), _m(m) { }
46
47 oop get_oop() { return _o; }
48 inline void set_mark() const;
49 void set_oop(oop obj) { _o = obj; }
50 };
51 typedef Stack<OopAndMarkWord, mtGC> OopAndMarkWordStack;
52
53 OopAndMarkWordStack _stack;
54
55 inline bool should_preserve_mark(oop obj, markWord m) const;
56
57 public:
58 size_t size() const { return _stack.size(); }
59 inline void push_if_necessary(oop obj, markWord m);
60 inline void push_always(oop obj, markWord m);
61 // Iterate over the stack, restore all preserved marks, and
62 // reclaim the memory taken up by the stack segments.
63 void restore();
64 // Iterate over the stack, adjust all preserved marks according
65 // to their forwarding location stored in the mark.
66 void adjust_during_full_gc();
67
68 void restore_and_increment(volatile size_t* const _total_size_addr);
69
70 // Assert the stack is empty and has no cached segments.
71 void assert_empty() PRODUCT_RETURN;
72
73 inline PreservedMarks();
74 ~PreservedMarks() { assert_empty(); }
75 };
76
77 class PreservedMarksSet : public CHeapObj<mtGC> {
78 private:
79 // true -> _stacks will be allocated in the C heap
80 // false -> _stacks will be allocated in the resource arena
81 const bool _in_c_heap;
82
83 // Number of stacks we have allocated (typically, one stack per GC worker).
84 // This should be >= 1 if the stacks have been initialized,
85 // or == 0 if they have not.
86 uint _num;
87
|
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_GC_SHARED_PRESERVEDMARKS_HPP
26 #define SHARE_GC_SHARED_PRESERVEDMARKS_HPP
27
28 #include "memory/allocation.hpp"
29 #include "memory/padded.hpp"
30 #include "oops/oop.hpp"
31 #include "utilities/stack.hpp"
32
33 class WorkerTask;
34 class PreservedMarksSet;
35 class SlidingForwarding;
36 class WorkerThreads;
37
38 class PreservedMarks {
39 private:
40 class OopAndMarkWord {
41 private:
42 oop _o;
43 markWord _m;
44
45 public:
46 OopAndMarkWord(oop obj, markWord m) : _o(obj), _m(m) { }
47
48 oop get_oop() { return _o; }
49 inline void set_mark() const;
50 void set_oop(oop obj) { _o = obj; }
51 };
52 typedef Stack<OopAndMarkWord, mtGC> OopAndMarkWordStack;
53
54 OopAndMarkWordStack _stack;
55
56 inline bool should_preserve_mark(oop obj, markWord m) const;
57
58 public:
59 size_t size() const { return _stack.size(); }
60 inline void push_if_necessary(oop obj, markWord m);
61 inline void push_always(oop obj, markWord m);
62 // Iterate over the stack, restore all preserved marks, and
63 // reclaim the memory taken up by the stack segments.
64 void restore();
65 // Iterate over the stack, adjust all preserved marks according
66 // to their forwarding location stored in the mark.
67 // TODO: This method is unused, except in the gunit test. Change the test
68 // to exercise the updated method below instead, and remove this one.
69 void adjust_during_full_gc();
70
71 void adjust_during_full_gc(const SlidingForwarding* const forwarding);
72
73 void restore_and_increment(volatile size_t* const _total_size_addr);
74
75 // Assert the stack is empty and has no cached segments.
76 void assert_empty() PRODUCT_RETURN;
77
78 inline PreservedMarks();
79 ~PreservedMarks() { assert_empty(); }
80 };
81
82 class PreservedMarksSet : public CHeapObj<mtGC> {
83 private:
84 // true -> _stacks will be allocated in the C heap
85 // false -> _stacks will be allocated in the resource arena
86 const bool _in_c_heap;
87
88 // Number of stacks we have allocated (typically, one stack per GC worker).
89 // This should be >= 1 if the stacks have been initialized,
90 // or == 0 if they have not.
91 uint _num;
92
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