1 #ifdef USE_PRAGMA_IDENT_HDR
2 #pragma ident "@(#)prefetchQueue.hpp 1.13 07/05/05 17:05:28 JVM"
3 #endif
4 /*
5 * Copyright 2002-2003 Sun Microsystems, Inc. All Rights Reserved.
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
7 *
8 * This code is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 only, as
10 * published by the Free Software Foundation.
11 *
12 * This code is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * version 2 for more details (a copy is included in the LICENSE file that
16 * accompanied this code).
17 *
18 * You should have received a copy of the GNU General Public License version
19 * 2 along with this work; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
24 * have any questions.
25 *
26 */
27
28 //
29 // PrefetchQueue is a FIFO queue of variable length (currently 8).
30 //
31 // We need to examine the performance penalty of variable lengths.
32 // We may also want to split this into cpu dependant bits.
33 //
34
35 const int PREFETCH_QUEUE_SIZE = 8;
36
37 class PrefetchQueue : public CHeapObj {
38 private:
39 oop* _prefetch_queue[PREFETCH_QUEUE_SIZE];
40 unsigned int _prefetch_index;
41
42 public:
43 int length() { return PREFETCH_QUEUE_SIZE; }
44
45 inline void clear() {
46 for(int i=0; i<PREFETCH_QUEUE_SIZE; i++) {
47 _prefetch_queue[i] = NULL;
48 }
49 _prefetch_index = 0;
50 }
51
52 inline oop* push_and_pop(oop* p) {
53 Prefetch::write((*p)->mark_addr(), 0);
54 // This prefetch is intended to make sure the size field of array
55 // oops is in cache. It assumes the the object layout is
56 // mark -> klass -> size, and that mark and klass are heapword
57 // sized. If this should change, this prefetch will need updating!
58 Prefetch::write((*p)->mark_addr() + (HeapWordSize*2), 0);
59 _prefetch_queue[_prefetch_index++] = p;
60 _prefetch_index &= (PREFETCH_QUEUE_SIZE-1);
61 return _prefetch_queue[_prefetch_index];
62 }
63
64 // Stores a NULL pointer in the pop'd location.
65 inline oop* pop() {
66 _prefetch_queue[_prefetch_index++] = NULL;
67 _prefetch_index &= (PREFETCH_QUEUE_SIZE-1);
68 return _prefetch_queue[_prefetch_index];
69 }
70 };
71
72
73
|
1 #ifdef USE_PRAGMA_IDENT_HDR
2 #pragma ident "@(#)prefetchQueue.hpp 1.13 07/05/05 17:05:28 JVM"
3 #endif
4 /*
5 * Copyright 2002-2008 Sun Microsystems, Inc. All Rights Reserved.
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
7 *
8 * This code is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 only, as
10 * published by the Free Software Foundation.
11 *
12 * This code is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * version 2 for more details (a copy is included in the LICENSE file that
16 * accompanied this code).
17 *
18 * You should have received a copy of the GNU General Public License version
19 * 2 along with this work; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
24 * have any questions.
25 *
26 */
27
28 //
29 // PrefetchQueue is a FIFO queue of variable length (currently 8).
30 //
31 // We need to examine the performance penalty of variable lengths.
32 // We may also want to split this into cpu dependant bits.
33 //
34
35 const int PREFETCH_QUEUE_SIZE = 8;
36
37 class PrefetchQueue : public CHeapObj {
38 private:
39 void* _prefetch_queue[PREFETCH_QUEUE_SIZE];
40 uint _prefetch_index;
41
42 public:
43 int length() { return PREFETCH_QUEUE_SIZE; }
44
45 inline void clear() {
46 for(int i=0; i<PREFETCH_QUEUE_SIZE; i++) {
47 _prefetch_queue[i] = NULL;
48 }
49 _prefetch_index = 0;
50 }
51
52 template <class T> inline void* push_and_pop(T* p) {
53 oop o = oopDesc::load_decode_heap_oop_not_null(p);
54 Prefetch::write(o->mark_addr(), 0);
55 // This prefetch is intended to make sure the size field of array
56 // oops is in cache. It assumes the the object layout is
57 // mark -> klass -> size, and that mark and klass are heapword
58 // sized. If this should change, this prefetch will need updating!
59 Prefetch::write(o->mark_addr() + (HeapWordSize*2), 0);
60 _prefetch_queue[_prefetch_index++] = p;
61 _prefetch_index &= (PREFETCH_QUEUE_SIZE-1);
62 return _prefetch_queue[_prefetch_index];
63 }
64
65 // Stores a NULL pointer in the pop'd location.
66 inline void* pop() {
67 _prefetch_queue[_prefetch_index++] = NULL;
68 _prefetch_index &= (PREFETCH_QUEUE_SIZE-1);
69 return _prefetch_queue[_prefetch_index];
70 }
71 };
72
73
74
|