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_GC_G1_G1FREEIDSET_HPP
26 #define SHARE_GC_G1_G1FREEIDSET_HPP
27
28 #include "memory/allocation.hpp"
29 #include "runtime/semaphore.hpp"
30 #include "utilities/globalDefinitions.hpp"
31
32 // Represents a set of small integer ids, from which elements can be
33 // temporarily allocated for exclusive use. The ids are in a
34 // contiguous range from 'start' to 'start + size'. Used to obtain a
35 // distinct worker_id value for a mutator thread that doesn't normally
36 // have such an id.
37 class G1FreeIdSet : public CHeapObj<mtGC> {
38 Semaphore _sem;
39 uint* _next;
40 uint _start;
41 uint _size;
42 uintx _head_index_mask;
43 volatile uintx _head;
44
45 uint head_index(uintx head) const;
46 uintx make_head(uint index, uintx old_head) const;
47
48 // Noncopyable.
49 G1FreeIdSet(const G1FreeIdSet&);
50 G1FreeIdSet& operator=(const G1FreeIdSet&);
51
52 public:
53 G1FreeIdSet(uint start, uint size);
54 ~G1FreeIdSet();
55
56 // Returns an unclaimed parallel id (waiting for one to be released if
57 // necessary). Must not safepoint while holding a claimed id.
|
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_GC_G1_G1FREEIDSET_HPP
26 #define SHARE_GC_G1_G1FREEIDSET_HPP
27
28 #include "runtime/semaphore.hpp"
29 #include "utilities/globalDefinitions.hpp"
30
31 // Represents a set of small integer ids, from which elements can be
32 // temporarily allocated for exclusive use. The ids are in a
33 // contiguous range from 'start' to 'start + size'. Used to obtain a
34 // distinct worker_id value for a mutator thread that doesn't normally
35 // have such an id.
36 class G1FreeIdSet {
37 Semaphore _sem;
38 uint* _next;
39 uint _start;
40 uint _size;
41 uintx _head_index_mask;
42 volatile uintx _head;
43
44 uint head_index(uintx head) const;
45 uintx make_head(uint index, uintx old_head) const;
46
47 // Noncopyable.
48 G1FreeIdSet(const G1FreeIdSet&);
49 G1FreeIdSet& operator=(const G1FreeIdSet&);
50
51 public:
52 G1FreeIdSet(uint start, uint size);
53 ~G1FreeIdSet();
54
55 // Returns an unclaimed parallel id (waiting for one to be released if
56 // necessary). Must not safepoint while holding a claimed id.
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