Mercurial > jdk8-mips64-public > hotspot / annotate
src/share/vm/memory/referencePolicy.cpp@d1bdeef3e3e2 (annotated)
src/share/vm/memory/referencePolicy.cpp
Wed, 12 Oct 2011 10:25:51 -0700
- author
- johnc
- date
- Wed, 12 Oct 2011 10:25:51 -0700
- changeset 3188
- d1bdeef3e3e2
- parent 2314
- f95d63e2154a
- child 6876
- 710a3c8b516e
- permissions
- -rw-r--r--
7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76
Summary: There is a race between one thread successfully forwarding and copying the klass mirror for the SoftReference class (including the static master clock) and another thread attempting to use the master clock while attempting to discover a soft reference object. Maintain a shadow copy of the soft reference master clock and use the shadow during reference discovery and reference processing.
Reviewed-by: tonyp, brutisso, ysr
| duke@435 | 1 | /* |
| johnc@3188 | 2 | * Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved. |
| duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| duke@435 | 4 | * |
| duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
| duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
| duke@435 | 7 | * published by the Free Software Foundation. |
| duke@435 | 8 | * |
| duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
| duke@435 | 13 | * accompanied this code). |
| duke@435 | 14 | * |
| duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
| duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
| duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| duke@435 | 18 | * |
| trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
| trims@1907 | 21 | * questions. |
| duke@435 | 22 | * |
| duke@435 | 23 | */ |
| duke@435 | 24 | |
| stefank@2314 | 25 | #include "precompiled.hpp" |
| stefank@2314 | 26 | #include "classfile/javaClasses.hpp" |
| stefank@2314 | 27 | #include "memory/referencePolicy.hpp" |
| stefank@2314 | 28 | #include "memory/universe.hpp" |
| stefank@2314 | 29 | #include "runtime/arguments.hpp" |
| stefank@2314 | 30 | #include "runtime/globals.hpp" |
| duke@435 | 31 | |
| duke@435 | 32 | LRUCurrentHeapPolicy::LRUCurrentHeapPolicy() { |
| ysr@892 | 33 | setup(); |
| ysr@888 | 34 | } |
| ysr@888 | 35 | |
| ysr@888 | 36 | // Capture state (of-the-VM) information needed to evaluate the policy |
| ysr@892 | 37 | void LRUCurrentHeapPolicy::setup() { |
| duke@435 | 38 | _max_interval = (Universe::get_heap_free_at_last_gc() / M) * SoftRefLRUPolicyMSPerMB; |
| duke@435 | 39 | assert(_max_interval >= 0,"Sanity check"); |
| duke@435 | 40 | } |
| duke@435 | 41 | |
| duke@435 | 42 | // The oop passed in is the SoftReference object, and not |
| duke@435 | 43 | // the object the SoftReference points to. |
| johnc@3188 | 44 | bool LRUCurrentHeapPolicy::should_clear_reference(oop p, |
| johnc@3188 | 45 | jlong timestamp_clock) { |
| johnc@3188 | 46 | jlong interval = timestamp_clock - java_lang_ref_SoftReference::timestamp(p); |
| duke@435 | 47 | assert(interval >= 0, "Sanity check"); |
| duke@435 | 48 | |
| duke@435 | 49 | // The interval will be zero if the ref was accessed since the last scavenge/gc. |
| duke@435 | 50 | if(interval <= _max_interval) { |
| duke@435 | 51 | return false; |
| duke@435 | 52 | } |
| duke@435 | 53 | |
| duke@435 | 54 | return true; |
| duke@435 | 55 | } |
| duke@435 | 56 | |
| duke@435 | 57 | /////////////////////// MaxHeap ////////////////////// |
| duke@435 | 58 | |
| duke@435 | 59 | LRUMaxHeapPolicy::LRUMaxHeapPolicy() { |
| ysr@892 | 60 | setup(); |
| ysr@888 | 61 | } |
| ysr@888 | 62 | |
| ysr@888 | 63 | // Capture state (of-the-VM) information needed to evaluate the policy |
| ysr@892 | 64 | void LRUMaxHeapPolicy::setup() { |
| duke@435 | 65 | size_t max_heap = MaxHeapSize; |
| duke@435 | 66 | max_heap -= Universe::get_heap_used_at_last_gc(); |
| duke@435 | 67 | max_heap /= M; |
| duke@435 | 68 | |
| duke@435 | 69 | _max_interval = max_heap * SoftRefLRUPolicyMSPerMB; |
| duke@435 | 70 | assert(_max_interval >= 0,"Sanity check"); |
| duke@435 | 71 | } |
| duke@435 | 72 | |
| duke@435 | 73 | // The oop passed in is the SoftReference object, and not |
| duke@435 | 74 | // the object the SoftReference points to. |
| johnc@3188 | 75 | bool LRUMaxHeapPolicy::should_clear_reference(oop p, |
| johnc@3188 | 76 | jlong timestamp_clock) { |
| johnc@3188 | 77 | jlong interval = timestamp_clock - java_lang_ref_SoftReference::timestamp(p); |
| duke@435 | 78 | assert(interval >= 0, "Sanity check"); |
| duke@435 | 79 | |
| duke@435 | 80 | // The interval will be zero if the ref was accessed since the last scavenge/gc. |
| duke@435 | 81 | if(interval <= _max_interval) { |
| duke@435 | 82 | return false; |
| duke@435 | 83 | } |
| duke@435 | 84 | |
| duke@435 | 85 | return true; |
| duke@435 | 86 | } |
