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_G1_PTRQUEUE_HPP
26 #define SHARE_VM_GC_G1_PTRQUEUE_HPP
27
28 #include "memory/allocation.hpp"
29 #include "utilities/align.hpp"
30 #include "utilities/sizes.hpp"
31
32 // There are various techniques that require threads to be able to log
33 // addresses. For example, a generational write barrier might log
34 // the addresses of modified old-generation objects. This type supports
35 // this operation.
36
37 class BufferNode;
38 class PtrQueueSet;
39 class PtrQueue VALUE_OBJ_CLASS_SPEC {
40 friend class VMStructs;
41
42 // Noncopyable - not defined.
43 PtrQueue(const PtrQueue&);
44 PtrQueue& operator=(const PtrQueue&);
45
46 // The ptr queue set to which this queue belongs.
47 PtrQueueSet* const _qset;
48
49 // Whether updates should be logged.
50 bool _active;
51
52 // If true, the queue is permanent, and doesn't need to deallocate
53 // its buffer in the destructor (since that obtains a lock which may not
54 // be legally locked by then.
55 const bool _permanent;
56
57 // The (byte) index at which an object was last enqueued. Starts at
58 // capacity_in_bytes (indicating an empty buffer) and goes towards zero.
59 // Value is always pointer-size aligned.
240 static BufferNode* make_node_from_buffer(void** buffer, size_t index) {
241 BufferNode* node =
242 reinterpret_cast<BufferNode*>(
243 reinterpret_cast<char*>(buffer) - buffer_offset());
244 node->set_index(index);
245 return node;
246 }
247
248 // Return the buffer for node.
249 static void** make_buffer_from_node(BufferNode *node) {
250 // &_buffer[0] might lead to index out of bounds warnings.
251 return reinterpret_cast<void**>(
252 reinterpret_cast<char*>(node) + buffer_offset());
253 }
254 };
255
256 // A PtrQueueSet represents resources common to a set of pointer queues.
257 // In particular, the individual queues allocate buffers from this shared
258 // set, and return completed buffers to the set.
259 // All these variables are are protected by the TLOQ_CBL_mon. XXX ???
260 class PtrQueueSet VALUE_OBJ_CLASS_SPEC {
261 private:
262 // The size of all buffers in the set.
263 size_t _buffer_size;
264
265 protected:
266 Monitor* _cbl_mon; // Protects the fields below.
267 BufferNode* _completed_buffers_head;
268 BufferNode* _completed_buffers_tail;
269 size_t _n_completed_buffers;
270 int _process_completed_threshold;
271 volatile bool _process_completed;
272
273 // This (and the interpretation of the first element as a "next"
274 // pointer) are protected by the TLOQ_FL_lock.
275 Mutex* _fl_lock;
276 BufferNode* _buf_free_list;
277 size_t _buf_free_list_sz;
278 // Queue set can share a freelist. The _fl_owner variable
279 // specifies the owner. It is set to "this" by default.
280 PtrQueueSet* _fl_owner;
|
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_G1_PTRQUEUE_HPP
26 #define SHARE_VM_GC_G1_PTRQUEUE_HPP
27
28 #include "utilities/align.hpp"
29 #include "utilities/sizes.hpp"
30
31 // There are various techniques that require threads to be able to log
32 // addresses. For example, a generational write barrier might log
33 // the addresses of modified old-generation objects. This type supports
34 // this operation.
35
36 class BufferNode;
37 class PtrQueueSet;
38 class PtrQueue {
39 friend class VMStructs;
40
41 // Noncopyable - not defined.
42 PtrQueue(const PtrQueue&);
43 PtrQueue& operator=(const PtrQueue&);
44
45 // The ptr queue set to which this queue belongs.
46 PtrQueueSet* const _qset;
47
48 // Whether updates should be logged.
49 bool _active;
50
51 // If true, the queue is permanent, and doesn't need to deallocate
52 // its buffer in the destructor (since that obtains a lock which may not
53 // be legally locked by then.
54 const bool _permanent;
55
56 // The (byte) index at which an object was last enqueued. Starts at
57 // capacity_in_bytes (indicating an empty buffer) and goes towards zero.
58 // Value is always pointer-size aligned.
239 static BufferNode* make_node_from_buffer(void** buffer, size_t index) {
240 BufferNode* node =
241 reinterpret_cast<BufferNode*>(
242 reinterpret_cast<char*>(buffer) - buffer_offset());
243 node->set_index(index);
244 return node;
245 }
246
247 // Return the buffer for node.
248 static void** make_buffer_from_node(BufferNode *node) {
249 // &_buffer[0] might lead to index out of bounds warnings.
250 return reinterpret_cast<void**>(
251 reinterpret_cast<char*>(node) + buffer_offset());
252 }
253 };
254
255 // A PtrQueueSet represents resources common to a set of pointer queues.
256 // In particular, the individual queues allocate buffers from this shared
257 // set, and return completed buffers to the set.
258 // All these variables are are protected by the TLOQ_CBL_mon. XXX ???
259 class PtrQueueSet {
260 private:
261 // The size of all buffers in the set.
262 size_t _buffer_size;
263
264 protected:
265 Monitor* _cbl_mon; // Protects the fields below.
266 BufferNode* _completed_buffers_head;
267 BufferNode* _completed_buffers_tail;
268 size_t _n_completed_buffers;
269 int _process_completed_threshold;
270 volatile bool _process_completed;
271
272 // This (and the interpretation of the first element as a "next"
273 // pointer) are protected by the TLOQ_FL_lock.
274 Mutex* _fl_lock;
275 BufferNode* _buf_free_list;
276 size_t _buf_free_list_sz;
277 // Queue set can share a freelist. The _fl_owner variable
278 // specifies the owner. It is set to "this" by default.
279 PtrQueueSet* _fl_owner;
|