Mercurial > jdk8-mips64-public > hotspot / file comparison
comparison: src/share/vm/gc_implementation/parallelScavenge/prefetchQueue.hpp
src/share/vm/gc_implementation/parallelScavenge/prefetchQueue.hpp
- changeset 2068
- 7fcd5f39bd7a
- parent 1907
- c18cbe5936b8
equal
deleted
inserted
replaced
| 2050:21e519b91576 | 2068:7fcd5f39bd7a |
|---|---|
| 1 /* | |
| 2 * Copyright (c) 2002, 2008, Oracle and/or its affiliates. All rights reserved. | |
| 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | |
| 4 * | |
| 5 * This code is free software; you can redistribute it and/or modify it | |
| 6 * under the terms of the GNU General Public License version 2 only, as | |
| 7 * published by the Free Software Foundation. | |
| 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 // | |
| 26 // PrefetchQueue is a FIFO queue of variable length (currently 8). | |
| 27 // | |
| 28 // We need to examine the performance penalty of variable lengths. | |
| 29 // We may also want to split this into cpu dependent bits. | |
| 30 // | |
| 31 | |
| 32 const int PREFETCH_QUEUE_SIZE = 8; | |
| 33 | |
| 34 class PrefetchQueue : public CHeapObj { | |
| 35 private: | |
| 36 void* _prefetch_queue[PREFETCH_QUEUE_SIZE]; | |
| 37 uint _prefetch_index; | |
| 38 | |
| 39 public: | |
| 40 int length() { return PREFETCH_QUEUE_SIZE; } | |
| 41 | |
| 42 inline void clear() { | |
| 43 for(int i=0; i<PREFETCH_QUEUE_SIZE; i++) { | |
| 44 _prefetch_queue[i] = NULL; | |
| 45 } | |
| 46 _prefetch_index = 0; | |
| 47 } | |
| 48 | |
| 49 template <class T> inline void* push_and_pop(T* p) { | |
| 50 oop o = oopDesc::load_decode_heap_oop_not_null(p); | |
| 51 Prefetch::write(o->mark_addr(), 0); | |
| 52 // This prefetch is intended to make sure the size field of array | |
| 53 // oops is in cache. It assumes the the object layout is | |
| 54 // mark -> klass -> size, and that mark and klass are heapword | |
| 55 // sized. If this should change, this prefetch will need updating! | |
| 56 Prefetch::write(o->mark_addr() + (HeapWordSize*2), 0); | |
| 57 _prefetch_queue[_prefetch_index++] = p; | |
| 58 _prefetch_index &= (PREFETCH_QUEUE_SIZE-1); | |
| 59 return _prefetch_queue[_prefetch_index]; | |
| 60 } | |
| 61 | |
| 62 // Stores a NULL pointer in the pop'd location. | |
| 63 inline void* pop() { | |
| 64 _prefetch_queue[_prefetch_index++] = NULL; | |
| 65 _prefetch_index &= (PREFETCH_QUEUE_SIZE-1); | |
| 66 return _prefetch_queue[_prefetch_index]; | |
| 67 } | |
| 68 }; |
