graal-compiler: src/share/vm/memory/referenceProcessor.cpp annotate

annotate src/share/vm/memory/referenceProcessor.cpp @ 20190:0982ec23da03

8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps Reviewed-by: jwilhelm, ehelin, tschatzl

author	brutisso
date	Thu, 19 Jun 2014 13:31:14 +0200
parents	8e20ef014b08
children	c2844108a708

rev	line source
0 a61af66fc99e Initial load duke parents: diff changeset	1 /*
17937 78bbf4d43a14 8037816: Fix for 8036122 breaks build with Xcode5/clang drchase parents: 17748 diff changeset	2 * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved.
0 a61af66fc99e Initial load duke parents: diff changeset	3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
a61af66fc99e Initial load duke parents: diff changeset	4 *
a61af66fc99e Initial load duke parents: diff changeset	5 * This code is free software; you can redistribute it and/or modify it
a61af66fc99e Initial load duke parents: diff changeset	6 * under the terms of the GNU General Public License version 2 only, as
a61af66fc99e Initial load duke parents: diff changeset	7 * published by the Free Software Foundation.
a61af66fc99e Initial load duke parents: diff changeset	8 *
a61af66fc99e Initial load duke parents: diff changeset	9 * This code is distributed in the hope that it will be useful, but WITHOUT
a61af66fc99e Initial load duke parents: diff changeset	10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
a61af66fc99e Initial load duke parents: diff changeset	11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
a61af66fc99e Initial load duke parents: diff changeset	12 * version 2 for more details (a copy is included in the LICENSE file that
a61af66fc99e Initial load duke parents: diff changeset	13 * accompanied this code).
a61af66fc99e Initial load duke parents: diff changeset	14 *
a61af66fc99e Initial load duke parents: diff changeset	15 * You should have received a copy of the GNU General Public License version
a61af66fc99e Initial load duke parents: diff changeset	16 * 2 along with this work; if not, write to the Free Software Foundation,
a61af66fc99e Initial load duke parents: diff changeset	17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
a61af66fc99e Initial load duke parents: diff changeset	18 *
1552 c18cbe5936b8 6941466: Oracle rebranding changes for Hotspot repositories trims parents: 1190 diff changeset	19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
c18cbe5936b8 6941466: Oracle rebranding changes for Hotspot repositories trims parents: 1190 diff changeset	20 * or visit www.oracle.com if you need additional information or have any
c18cbe5936b8 6941466: Oracle rebranding changes for Hotspot repositories trims parents: 1190 diff changeset	21 * questions.
0 a61af66fc99e Initial load duke parents: diff changeset	22 *
a61af66fc99e Initial load duke parents: diff changeset	23 */
a61af66fc99e Initial load duke parents: diff changeset	24
1972 f95d63e2154a 6989984: Use standard include model for Hospot stefank parents: 1833 diff changeset	25 #include "precompiled.hpp"
f95d63e2154a 6989984: Use standard include model for Hospot stefank parents: 1833 diff changeset	26 #include "classfile/javaClasses.hpp"
f95d63e2154a 6989984: Use standard include model for Hospot stefank parents: 1833 diff changeset	27 #include "classfile/systemDictionary.hpp"
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	28 #include "gc_implementation/shared/gcTimer.hpp"
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	29 #include "gc_implementation/shared/gcTraceTime.hpp"
1972 f95d63e2154a 6989984: Use standard include model for Hospot stefank parents: 1833 diff changeset	30 #include "gc_interface/collectedHeap.hpp"
f95d63e2154a 6989984: Use standard include model for Hospot stefank parents: 1833 diff changeset	31 #include "gc_interface/collectedHeap.inline.hpp"
f95d63e2154a 6989984: Use standard include model for Hospot stefank parents: 1833 diff changeset	32 #include "memory/referencePolicy.hpp"
f95d63e2154a 6989984: Use standard include model for Hospot stefank parents: 1833 diff changeset	33 #include "memory/referenceProcessor.hpp"
f95d63e2154a 6989984: Use standard include model for Hospot stefank parents: 1833 diff changeset	34 #include "oops/oop.inline.hpp"
f95d63e2154a 6989984: Use standard include model for Hospot stefank parents: 1833 diff changeset	35 #include "runtime/java.hpp"
f95d63e2154a 6989984: Use standard include model for Hospot stefank parents: 1833 diff changeset	36 #include "runtime/jniHandles.hpp"
0 a61af66fc99e Initial load duke parents: diff changeset	37
17937 78bbf4d43a14 8037816: Fix for 8036122 breaks build with Xcode5/clang drchase parents: 17748 diff changeset	38 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
78bbf4d43a14 8037816: Fix for 8036122 breaks build with Xcode5/clang drchase parents: 17748 diff changeset	39
453 c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	40 ReferencePolicy* ReferenceProcessor::_always_clear_soft_ref_policy = NULL;
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	41 ReferencePolicy* ReferenceProcessor::_default_soft_ref_policy = NULL;
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	42 bool ReferenceProcessor::_pending_list_uses_discovered_field = false;
3992 d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	43 jlong ReferenceProcessor::_soft_ref_timestamp_clock = 0;
453 c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	44
0 a61af66fc99e Initial load duke parents: diff changeset	45 void referenceProcessor_init() {
a61af66fc99e Initial load duke parents: diff changeset	46 ReferenceProcessor::init_statics();
a61af66fc99e Initial load duke parents: diff changeset	47 }
a61af66fc99e Initial load duke parents: diff changeset	48
a61af66fc99e Initial load duke parents: diff changeset	49 void ReferenceProcessor::init_statics() {
4712 e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	50 // We need a monotonically non-deccreasing time in ms but
e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	51 // os::javaTimeMillis() does not guarantee monotonicity.
e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	52 jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
3992 d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	53
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	54 // Initialize the soft ref timestamp clock.
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	55 _soft_ref_timestamp_clock = now;
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	56 // Also update the soft ref clock in j.l.r.SoftReference
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	57 java_lang_ref_SoftReference::set_clock(_soft_ref_timestamp_clock);
0 a61af66fc99e Initial load duke parents: diff changeset	58
453 c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	59 _always_clear_soft_ref_policy = new AlwaysClearPolicy();
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	60 _default_soft_ref_policy = new COMPILER2_PRESENT(LRUMaxHeapPolicy())
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	61 NOT_COMPILER2(LRUCurrentHeapPolicy());
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	62 if (_always_clear_soft_ref_policy == NULL \|\| _default_soft_ref_policy == NULL) {
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	63 vm_exit_during_initialization("Could not allocate reference policy object");
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	64 }
0 a61af66fc99e Initial load duke parents: diff changeset	65 guarantee(RefDiscoveryPolicy == ReferenceBasedDiscovery \|\|
a61af66fc99e Initial load duke parents: diff changeset	66 RefDiscoveryPolicy == ReferentBasedDiscovery,
a61af66fc99e Initial load duke parents: diff changeset	67 "Unrecongnized RefDiscoveryPolicy");
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	68 _pending_list_uses_discovered_field = JDK_Version::current().pending_list_uses_discovered_field();
0 a61af66fc99e Initial load duke parents: diff changeset	69 }
a61af66fc99e Initial load duke parents: diff changeset	70
3992 d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	71 void ReferenceProcessor::enable_discovery(bool verify_disabled, bool check_no_refs) {
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	72 #ifdef ASSERT
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	73 // Verify that we're not currently discovering refs
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	74 assert(!verify_disabled \|\| !_discovering_refs, "nested call?");
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	75
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	76 if (check_no_refs) {
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	77 // Verify that the discovered lists are empty
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	78 verify_no_references_recorded();
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	79 }
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	80 #endif // ASSERT
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	81
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	82 // Someone could have modified the value of the static
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	83 // field in the j.l.r.SoftReference class that holds the
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	84 // soft reference timestamp clock using reflection or
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	85 // Unsafe between GCs. Unconditionally update the static
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	86 // field in ReferenceProcessor here so that we use the new
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	87 // value during reference discovery.
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	88
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	89 _soft_ref_timestamp_clock = java_lang_ref_SoftReference::clock();
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	90 _discovering_refs = true;
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	91 }
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	92
0 a61af66fc99e Initial load duke parents: diff changeset	93 ReferenceProcessor::ReferenceProcessor(MemRegion span,
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	94 bool mt_processing,
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	95 uint mt_processing_degree,
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	96 bool mt_discovery,
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	97 uint mt_discovery_degree,
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	98 bool atomic_discovery,
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	99 BoolObjectClosure* is_alive_non_header) :
0 a61af66fc99e Initial load duke parents: diff changeset	100 _discovering_refs(false),
a61af66fc99e Initial load duke parents: diff changeset	101 _enqueuing_is_done(false),
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	102 _is_alive_non_header(is_alive_non_header),
0 a61af66fc99e Initial load duke parents: diff changeset	103 _processing_is_mt(mt_processing),
a61af66fc99e Initial load duke parents: diff changeset	104 _next_id(0)
a61af66fc99e Initial load duke parents: diff changeset	105 {
a61af66fc99e Initial load duke parents: diff changeset	106 _span = span;
a61af66fc99e Initial load duke parents: diff changeset	107 _discovery_is_atomic = atomic_discovery;
a61af66fc99e Initial load duke parents: diff changeset	108 _discovery_is_mt = mt_discovery;
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	109 _num_q = MAX2(1U, mt_processing_degree);
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	110 _max_num_q = MAX2(_num_q, mt_discovery_degree);
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	111 _discovered_refs = NEW_C_HEAP_ARRAY(DiscoveredList,
6197 d2a62e0f25eb 6995781: Native Memory Tracking (Phase 1) zgu parents: 4728 diff changeset	112 _max_num_q * number_of_subclasses_of_ref(), mtGC);
d2a62e0f25eb 6995781: Native Memory Tracking (Phase 1) zgu parents: 4728 diff changeset	113
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	114 if (_discovered_refs == NULL) {
0 a61af66fc99e Initial load duke parents: diff changeset	115 vm_exit_during_initialization("Could not allocated RefProc Array");
a61af66fc99e Initial load duke parents: diff changeset	116 }
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	117 _discoveredSoftRefs = &_discovered_refs[0];
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	118 _discoveredWeakRefs = &_discoveredSoftRefs[_max_num_q];
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	119 _discoveredFinalRefs = &_discoveredWeakRefs[_max_num_q];
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	120 _discoveredPhantomRefs = &_discoveredFinalRefs[_max_num_q];
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	121
bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	122 // Initialize all entries to NULL
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	123 for (uint i = 0; i < _max_num_q * number_of_subclasses_of_ref(); i++) {
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	124 _discovered_refs[i].set_head(NULL);
bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	125 _discovered_refs[i].set_length(0);
0 a61af66fc99e Initial load duke parents: diff changeset	126 }
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	127
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	128 setup_policy(false /* default soft ref policy */);
0 a61af66fc99e Initial load duke parents: diff changeset	129 }
a61af66fc99e Initial load duke parents: diff changeset	130
a61af66fc99e Initial load duke parents: diff changeset	131 #ifndef PRODUCT
a61af66fc99e Initial load duke parents: diff changeset	132 void ReferenceProcessor::verify_no_references_recorded() {
a61af66fc99e Initial load duke parents: diff changeset	133 guarantee(!_discovering_refs, "Discovering refs?");
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	134 for (uint i = 0; i < _max_num_q * number_of_subclasses_of_ref(); i++) {
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	135 guarantee(_discovered_refs[i].is_empty(),
0 a61af66fc99e Initial load duke parents: diff changeset	136 "Found non-empty discovered list");
a61af66fc99e Initial load duke parents: diff changeset	137 }
a61af66fc99e Initial load duke parents: diff changeset	138 }
a61af66fc99e Initial load duke parents: diff changeset	139 #endif
a61af66fc99e Initial load duke parents: diff changeset	140
a61af66fc99e Initial load duke parents: diff changeset	141 void ReferenceProcessor::weak_oops_do(OopClosure* f) {
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	142 for (uint i = 0; i < _max_num_q * number_of_subclasses_of_ref(); i++) {
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	143 if (UseCompressedOops) {
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	144 f->do_oop((narrowOop*)_discovered_refs[i].adr_head());
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	145 } else {
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	146 f->do_oop((oop*)_discovered_refs[i].adr_head());
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	147 }
0 a61af66fc99e Initial load duke parents: diff changeset	148 }
a61af66fc99e Initial load duke parents: diff changeset	149 }
a61af66fc99e Initial load duke parents: diff changeset	150
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	151 void ReferenceProcessor::update_soft_ref_master_clock() {
0 a61af66fc99e Initial load duke parents: diff changeset	152 // Update (advance) the soft ref master clock field. This must be done
a61af66fc99e Initial load duke parents: diff changeset	153 // after processing the soft ref list.
4712 e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	154
e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	155 // We need a monotonically non-deccreasing time in ms but
e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	156 // os::javaTimeMillis() does not guarantee monotonicity.
e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	157 jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
3992 d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	158 jlong soft_ref_clock = java_lang_ref_SoftReference::clock();
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	159 assert(soft_ref_clock == _soft_ref_timestamp_clock, "soft ref clocks out of sync");
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	160
0 a61af66fc99e Initial load duke parents: diff changeset	161 NOT_PRODUCT(
3992 d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	162 if (now < _soft_ref_timestamp_clock) {
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	163 warning("time warp: "INT64_FORMAT" to "INT64_FORMAT,
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	164 _soft_ref_timestamp_clock, now);
0 a61af66fc99e Initial load duke parents: diff changeset	165 }
a61af66fc99e Initial load duke parents: diff changeset	166 )
4712 e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	167 // The values of now and _soft_ref_timestamp_clock are set using
e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	168 // javaTimeNanos(), which is guaranteed to be monotonically
e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	169 // non-decreasing provided the underlying platform provides such
e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	170 // a time source (and it is bug free).
e7dead7e90af 7117303: VM uses non-monotonic time source and complains that it is non-monotonic johnc parents: 4014 diff changeset	171 // In product mode, however, protect ourselves from non-monotonicty.
3992 d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	172 if (now > _soft_ref_timestamp_clock) {
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	173 _soft_ref_timestamp_clock = now;
0 a61af66fc99e Initial load duke parents: diff changeset	174 java_lang_ref_SoftReference::set_clock(now);
a61af66fc99e Initial load duke parents: diff changeset	175 }
a61af66fc99e Initial load duke parents: diff changeset	176 // Else leave clock stalled at its old value until time progresses
a61af66fc99e Initial load duke parents: diff changeset	177 // past clock value.
a61af66fc99e Initial load duke parents: diff changeset	178 }
a61af66fc99e Initial load duke parents: diff changeset	179
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	180 size_t ReferenceProcessor::total_count(DiscoveredList lists[]) {
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	181 size_t total = 0;
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	182 for (uint i = 0; i < _max_num_q; ++i) {
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	183 total += lists[i].length();
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	184 }
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	185 return total;
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	186 }
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	187
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	188 ReferenceProcessorStats ReferenceProcessor::process_discovered_references(
0 a61af66fc99e Initial load duke parents: diff changeset	189 BoolObjectClosure* is_alive,
a61af66fc99e Initial load duke parents: diff changeset	190 OopClosure* keep_alive,
a61af66fc99e Initial load duke parents: diff changeset	191 VoidClosure* complete_gc,
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	192 AbstractRefProcTaskExecutor* task_executor,
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	193 GCTimer* gc_timer,
0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	194 GCId gc_id) {
0 a61af66fc99e Initial load duke parents: diff changeset	195 NOT_PRODUCT(verify_ok_to_handle_reflists());
a61af66fc99e Initial load duke parents: diff changeset	196
a61af66fc99e Initial load duke parents: diff changeset	197 assert(!enqueuing_is_done(), "If here enqueuing should not be complete");
a61af66fc99e Initial load duke parents: diff changeset	198 // Stop treating discovered references specially.
a61af66fc99e Initial load duke parents: diff changeset	199 disable_discovery();
a61af66fc99e Initial load duke parents: diff changeset	200
3992 d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	201 // If discovery was concurrent, someone could have modified
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	202 // the value of the static field in the j.l.r.SoftReference
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	203 // class that holds the soft reference timestamp clock using
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	204 // reflection or Unsafe between when discovery was enabled and
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	205 // now. Unconditionally update the static field in ReferenceProcessor
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	206 // here so that we use the new value during processing of the
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	207 // discovered soft refs.
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	208
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	209 _soft_ref_timestamp_clock = java_lang_ref_SoftReference::clock();
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	210
0 a61af66fc99e Initial load duke parents: diff changeset	211 bool trace_time = PrintGCDetails && PrintReferenceGC;
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	212
0 a61af66fc99e Initial load duke parents: diff changeset	213 // Soft references
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	214 size_t soft_count = 0;
0 a61af66fc99e Initial load duke parents: diff changeset	215 {
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	216 GCTraceTime tt("SoftReference", trace_time, false, gc_timer, gc_id);
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	217 soft_count =
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	218 process_discovered_reflist(_discoveredSoftRefs, _current_soft_ref_policy, true,
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	219 is_alive, keep_alive, complete_gc, task_executor);
0 a61af66fc99e Initial load duke parents: diff changeset	220 }
a61af66fc99e Initial load duke parents: diff changeset	221
a61af66fc99e Initial load duke parents: diff changeset	222 update_soft_ref_master_clock();
a61af66fc99e Initial load duke parents: diff changeset	223
a61af66fc99e Initial load duke parents: diff changeset	224 // Weak references
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	225 size_t weak_count = 0;
0 a61af66fc99e Initial load duke parents: diff changeset	226 {
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	227 GCTraceTime tt("WeakReference", trace_time, false, gc_timer, gc_id);
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	228 weak_count =
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	229 process_discovered_reflist(_discoveredWeakRefs, NULL, true,
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	230 is_alive, keep_alive, complete_gc, task_executor);
0 a61af66fc99e Initial load duke parents: diff changeset	231 }
a61af66fc99e Initial load duke parents: diff changeset	232
a61af66fc99e Initial load duke parents: diff changeset	233 // Final references
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	234 size_t final_count = 0;
0 a61af66fc99e Initial load duke parents: diff changeset	235 {
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	236 GCTraceTime tt("FinalReference", trace_time, false, gc_timer, gc_id);
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	237 final_count =
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	238 process_discovered_reflist(_discoveredFinalRefs, NULL, false,
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	239 is_alive, keep_alive, complete_gc, task_executor);
0 a61af66fc99e Initial load duke parents: diff changeset	240 }
a61af66fc99e Initial load duke parents: diff changeset	241
a61af66fc99e Initial load duke parents: diff changeset	242 // Phantom references
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	243 size_t phantom_count = 0;
0 a61af66fc99e Initial load duke parents: diff changeset	244 {
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	245 GCTraceTime tt("PhantomReference", trace_time, false, gc_timer, gc_id);
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	246 phantom_count =
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	247 process_discovered_reflist(_discoveredPhantomRefs, NULL, false,
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	248 is_alive, keep_alive, complete_gc, task_executor);
0 a61af66fc99e Initial load duke parents: diff changeset	249 }
a61af66fc99e Initial load duke parents: diff changeset	250
a61af66fc99e Initial load duke parents: diff changeset	251 // Weak global JNI references. It would make more sense (semantically) to
a61af66fc99e Initial load duke parents: diff changeset	252 // traverse these simultaneously with the regular weak references above, but
a61af66fc99e Initial load duke parents: diff changeset	253 // that is not how the JDK1.2 specification is. See #4126360. Native code can
a61af66fc99e Initial load duke parents: diff changeset	254 // thus use JNI weak references to circumvent the phantom references and
a61af66fc99e Initial load duke parents: diff changeset	255 // resurrect a "post-mortem" object.
a61af66fc99e Initial load duke parents: diff changeset	256 {
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	257 GCTraceTime tt("JNI Weak Reference", trace_time, false, gc_timer, gc_id);
0 a61af66fc99e Initial load duke parents: diff changeset	258 if (task_executor != NULL) {
a61af66fc99e Initial load duke parents: diff changeset	259 task_executor->set_single_threaded_mode();
a61af66fc99e Initial load duke parents: diff changeset	260 }
a61af66fc99e Initial load duke parents: diff changeset	261 process_phaseJNI(is_alive, keep_alive, complete_gc);
a61af66fc99e Initial load duke parents: diff changeset	262 }
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	263
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	264 return ReferenceProcessorStats(soft_count, weak_count, final_count, phantom_count);
0 a61af66fc99e Initial load duke parents: diff changeset	265 }
a61af66fc99e Initial load duke parents: diff changeset	266
a61af66fc99e Initial load duke parents: diff changeset	267 #ifndef PRODUCT
a61af66fc99e Initial load duke parents: diff changeset	268 // Calculate the number of jni handles.
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	269 uint ReferenceProcessor::count_jni_refs() {
0 a61af66fc99e Initial load duke parents: diff changeset	270 class AlwaysAliveClosure: public BoolObjectClosure {
a61af66fc99e Initial load duke parents: diff changeset	271 public:
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	272 virtual bool do_object_b(oop obj) { return true; }
0 a61af66fc99e Initial load duke parents: diff changeset	273 };
a61af66fc99e Initial load duke parents: diff changeset	274
a61af66fc99e Initial load duke parents: diff changeset	275 class CountHandleClosure: public OopClosure {
a61af66fc99e Initial load duke parents: diff changeset	276 private:
a61af66fc99e Initial load duke parents: diff changeset	277 int _count;
a61af66fc99e Initial load duke parents: diff changeset	278 public:
a61af66fc99e Initial load duke parents: diff changeset	279 CountHandleClosure(): _count(0) {}
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	280 void do_oop(oop* unused) { _count++; }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	281 void do_oop(narrowOop* unused) { ShouldNotReachHere(); }
0 a61af66fc99e Initial load duke parents: diff changeset	282 int count() { return _count; }
a61af66fc99e Initial load duke parents: diff changeset	283 };
a61af66fc99e Initial load duke parents: diff changeset	284 CountHandleClosure global_handle_count;
a61af66fc99e Initial load duke parents: diff changeset	285 AlwaysAliveClosure always_alive;
a61af66fc99e Initial load duke parents: diff changeset	286 JNIHandles::weak_oops_do(&always_alive, &global_handle_count);
a61af66fc99e Initial load duke parents: diff changeset	287 return global_handle_count.count();
a61af66fc99e Initial load duke parents: diff changeset	288 }
a61af66fc99e Initial load duke parents: diff changeset	289 #endif
a61af66fc99e Initial load duke parents: diff changeset	290
a61af66fc99e Initial load duke parents: diff changeset	291 void ReferenceProcessor::process_phaseJNI(BoolObjectClosure* is_alive,
a61af66fc99e Initial load duke parents: diff changeset	292 OopClosure* keep_alive,
a61af66fc99e Initial load duke parents: diff changeset	293 VoidClosure* complete_gc) {
a61af66fc99e Initial load duke parents: diff changeset	294 #ifndef PRODUCT
a61af66fc99e Initial load duke parents: diff changeset	295 if (PrintGCDetails && PrintReferenceGC) {
a61af66fc99e Initial load duke parents: diff changeset	296 unsigned int count = count_jni_refs();
a61af66fc99e Initial load duke parents: diff changeset	297 gclog_or_tty->print(", %u refs", count);
a61af66fc99e Initial load duke parents: diff changeset	298 }
a61af66fc99e Initial load duke parents: diff changeset	299 #endif
a61af66fc99e Initial load duke parents: diff changeset	300 JNIHandles::weak_oops_do(is_alive, keep_alive);
a61af66fc99e Initial load duke parents: diff changeset	301 complete_gc->do_void();
a61af66fc99e Initial load duke parents: diff changeset	302 }
a61af66fc99e Initial load duke parents: diff changeset	303
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	304
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	305 template <class T>
1123 167c2986d91b 6843629: Make current hotspot build part of jdk5 control build phh parents: 935 diff changeset	306 bool enqueue_discovered_ref_helper(ReferenceProcessor* ref,
167c2986d91b 6843629: Make current hotspot build part of jdk5 control build phh parents: 935 diff changeset	307 AbstractRefProcTaskExecutor* task_executor) {
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	308
0 a61af66fc99e Initial load duke parents: diff changeset	309 // Remember old value of pending references list
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	310 T* pending_list_addr = (T*)java_lang_ref_Reference::pending_list_addr();
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	311 T old_pending_list_value = *pending_list_addr;
0 a61af66fc99e Initial load duke parents: diff changeset	312
a61af66fc99e Initial load duke parents: diff changeset	313 // Enqueue references that are not made active again, and
a61af66fc99e Initial load duke parents: diff changeset	314 // clear the decks for the next collection (cycle).
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	315 ref->enqueue_discovered_reflists((HeapWord*)pending_list_addr, task_executor);
17746 a258f8cb530f 8029255: G1: Reference processing should not enqueue references on the shared SATB queue pliden parents: 12316 diff changeset	316 // Do the post-barrier on pending_list_addr missed in
a258f8cb530f 8029255: G1: Reference processing should not enqueue references on the shared SATB queue pliden parents: 12316 diff changeset	317 // enqueue_discovered_reflist.
a258f8cb530f 8029255: G1: Reference processing should not enqueue references on the shared SATB queue pliden parents: 12316 diff changeset	318 oopDesc::bs()->write_ref_field(pending_list_addr, oopDesc::load_decode_heap_oop(pending_list_addr));
0 a61af66fc99e Initial load duke parents: diff changeset	319
a61af66fc99e Initial load duke parents: diff changeset	320 // Stop treating discovered references specially.
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	321 ref->disable_discovery();
0 a61af66fc99e Initial load duke parents: diff changeset	322
a61af66fc99e Initial load duke parents: diff changeset	323 // Return true if new pending references were added
a61af66fc99e Initial load duke parents: diff changeset	324 return old_pending_list_value != *pending_list_addr;
a61af66fc99e Initial load duke parents: diff changeset	325 }
a61af66fc99e Initial load duke parents: diff changeset	326
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	327 bool ReferenceProcessor::enqueue_discovered_references(AbstractRefProcTaskExecutor* task_executor) {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	328 NOT_PRODUCT(verify_ok_to_handle_reflists());
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	329 if (UseCompressedOops) {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	330 return enqueue_discovered_ref_helper<narrowOop>(this, task_executor);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	331 } else {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	332 return enqueue_discovered_ref_helper<oop>(this, task_executor);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	333 }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	334 }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	335
0 a61af66fc99e Initial load duke parents: diff changeset	336 void ReferenceProcessor::enqueue_discovered_reflist(DiscoveredList& refs_list,
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	337 HeapWord* pending_list_addr) {
0 a61af66fc99e Initial load duke parents: diff changeset	338 // Given a list of refs linked through the "discovered" field
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	339 // (java.lang.ref.Reference.discovered), self-loop their "next" field
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	340 // thus distinguishing them from active References, then
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	341 // prepend them to the pending list.
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	342 //
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	343 // The Java threads will see the Reference objects linked together through
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	344 // the discovered field. Instead of trying to do the write barrier updates
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	345 // in all places in the reference processor where we manipulate the discovered
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	346 // field we make sure to do the barrier here where we anyway iterate through
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	347 // all linked Reference objects. Note that it is important to not dirty any
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	348 // cards during reference processing since this will cause card table
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	349 // verification to fail for G1.
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	350 //
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	351 // BKWRD COMPATIBILITY NOTE: For older JDKs (prior to the fix for 4956777),
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	352 // the "next" field is used to chain the pending list, not the discovered
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	353 // field.
0 a61af66fc99e Initial load duke parents: diff changeset	354 if (TraceReferenceGC && PrintGCDetails) {
a61af66fc99e Initial load duke parents: diff changeset	355 gclog_or_tty->print_cr("ReferenceProcessor::enqueue_discovered_reflist list "
a61af66fc99e Initial load duke parents: diff changeset	356 INTPTR_FORMAT, (address)refs_list.head());
a61af66fc99e Initial load duke parents: diff changeset	357 }
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	358
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	359 oop obj = NULL;
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	360 oop next_d = refs_list.head();
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	361 if (pending_list_uses_discovered_field()) { // New behavior
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	362 // Walk down the list, self-looping the next field
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	363 // so that the References are not considered active.
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	364 while (obj != next_d) {
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	365 obj = next_d;
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	366 assert(obj->is_instanceRef(), "should be reference object");
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	367 next_d = java_lang_ref_Reference::discovered(obj);
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	368 if (TraceReferenceGC && PrintGCDetails) {
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	369 gclog_or_tty->print_cr(" obj " INTPTR_FORMAT "/next_d " INTPTR_FORMAT,
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	370 (void )obj, (void )next_d);
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	371 }
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	372 assert(java_lang_ref_Reference::next(obj) == NULL,
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	373 "Reference not active; should not be discovered");
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	374 // Self-loop next, so as to make Ref not active.
17746 a258f8cb530f 8029255: G1: Reference processing should not enqueue references on the shared SATB queue pliden parents: 12316 diff changeset	375 java_lang_ref_Reference::set_next_raw(obj, obj);
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	376 if (next_d != obj) {
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	377 oopDesc::bs()->write_ref_field(java_lang_ref_Reference::discovered_addr(obj), next_d);
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	378 } else {
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	379 // This is the last object.
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	380 // Swap refs_list into pending_list_addr and
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	381 // set obj's discovered to what we read from pending_list_addr.
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	382 oop old = oopDesc::atomic_exchange_oop(refs_list.head(), pending_list_addr);
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	383 // Need post-barrier on pending_list_addr. See enqueue_discovered_ref_helper() above.
17746 a258f8cb530f 8029255: G1: Reference processing should not enqueue references on the shared SATB queue pliden parents: 12316 diff changeset	384 java_lang_ref_Reference::set_discovered_raw(obj, old); // old may be NULL
a258f8cb530f 8029255: G1: Reference processing should not enqueue references on the shared SATB queue pliden parents: 12316 diff changeset	385 oopDesc::bs()->write_ref_field(java_lang_ref_Reference::discovered_addr(obj), old);
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	386 }
0 a61af66fc99e Initial load duke parents: diff changeset	387 }
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	388 } else { // Old behaviour
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	389 // Walk down the list, copying the discovered field into
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	390 // the next field and clearing the discovered field.
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	391 while (obj != next_d) {
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	392 obj = next_d;
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	393 assert(obj->is_instanceRef(), "should be reference object");
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	394 next_d = java_lang_ref_Reference::discovered(obj);
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	395 if (TraceReferenceGC && PrintGCDetails) {
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	396 gclog_or_tty->print_cr(" obj " INTPTR_FORMAT "/next_d " INTPTR_FORMAT,
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	397 (void )obj, (void )next_d);
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	398 }
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	399 assert(java_lang_ref_Reference::next(obj) == NULL,
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	400 "The reference should not be enqueued");
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	401 if (next_d == obj) { // obj is last
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	402 // Swap refs_list into pendling_list_addr and
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	403 // set obj's next to what we read from pending_list_addr.
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	404 oop old = oopDesc::atomic_exchange_oop(refs_list.head(), pending_list_addr);
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	405 // Need oop_check on pending_list_addr above;
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	406 // see special oop-check code at the end of
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	407 // enqueue_discovered_reflists() further below.
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	408 if (old == NULL) {
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	409 // obj should be made to point to itself, since
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	410 // pending list was empty.
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	411 java_lang_ref_Reference::set_next(obj, obj);
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	412 } else {
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	413 java_lang_ref_Reference::set_next(obj, old);
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	414 }
0 a61af66fc99e Initial load duke parents: diff changeset	415 } else {
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	416 java_lang_ref_Reference::set_next(obj, next_d);
0 a61af66fc99e Initial load duke parents: diff changeset	417 }
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	418 java_lang_ref_Reference::set_discovered(obj, (oop) NULL);
0 a61af66fc99e Initial load duke parents: diff changeset	419 }
a61af66fc99e Initial load duke parents: diff changeset	420 }
a61af66fc99e Initial load duke parents: diff changeset	421 }
a61af66fc99e Initial load duke parents: diff changeset	422
a61af66fc99e Initial load duke parents: diff changeset	423 // Parallel enqueue task
a61af66fc99e Initial load duke parents: diff changeset	424 class RefProcEnqueueTask: public AbstractRefProcTaskExecutor::EnqueueTask {
a61af66fc99e Initial load duke parents: diff changeset	425 public:
a61af66fc99e Initial load duke parents: diff changeset	426 RefProcEnqueueTask(ReferenceProcessor& ref_processor,
a61af66fc99e Initial load duke parents: diff changeset	427 DiscoveredList discovered_refs[],
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	428 HeapWord* pending_list_addr,
0 a61af66fc99e Initial load duke parents: diff changeset	429 int n_queues)
a61af66fc99e Initial load duke parents: diff changeset	430 : EnqueueTask(ref_processor, discovered_refs,
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	431 pending_list_addr, n_queues)
0 a61af66fc99e Initial load duke parents: diff changeset	432 { }
a61af66fc99e Initial load duke parents: diff changeset	433
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	434 virtual void work(unsigned int work_id) {
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	435 assert(work_id < (unsigned int)_ref_processor.max_num_q(), "Index out-of-bounds");
0 a61af66fc99e Initial load duke parents: diff changeset	436 // Simplest first cut: static partitioning.
a61af66fc99e Initial load duke parents: diff changeset	437 int index = work_id;
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	438 // The increment on "index" must correspond to the maximum number of queues
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	439 // (n_queues) with which that ReferenceProcessor was created. That
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	440 // is because of the "clever" way the discovered references lists were
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	441 // allocated and are indexed into.
92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	442 assert(_n_queues == (int) _ref_processor.max_num_q(), "Different number not expected");
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	443 for (int j = 0;
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	444 j < ReferenceProcessor::number_of_subclasses_of_ref();
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	445 j++, index += _n_queues) {
0 a61af66fc99e Initial load duke parents: diff changeset	446 _ref_processor.enqueue_discovered_reflist(
a61af66fc99e Initial load duke parents: diff changeset	447 _refs_lists[index], _pending_list_addr);
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	448 _refs_lists[index].set_head(NULL);
0 a61af66fc99e Initial load duke parents: diff changeset	449 _refs_lists[index].set_length(0);
a61af66fc99e Initial load duke parents: diff changeset	450 }
a61af66fc99e Initial load duke parents: diff changeset	451 }
a61af66fc99e Initial load duke parents: diff changeset	452 };
a61af66fc99e Initial load duke parents: diff changeset	453
a61af66fc99e Initial load duke parents: diff changeset	454 // Enqueue references that are not made active again
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	455 void ReferenceProcessor::enqueue_discovered_reflists(HeapWord* pending_list_addr,
0 a61af66fc99e Initial load duke parents: diff changeset	456 AbstractRefProcTaskExecutor* task_executor) {
a61af66fc99e Initial load duke parents: diff changeset	457 if (_processing_is_mt && task_executor != NULL) {
a61af66fc99e Initial load duke parents: diff changeset	458 // Parallel code
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	459 RefProcEnqueueTask tsk(*this, _discovered_refs,
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	460 pending_list_addr, _max_num_q);
0 a61af66fc99e Initial load duke parents: diff changeset	461 task_executor->execute(tsk);
a61af66fc99e Initial load duke parents: diff changeset	462 } else {
a61af66fc99e Initial load duke parents: diff changeset	463 // Serial code: call the parent class's implementation
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	464 for (uint i = 0; i < _max_num_q * number_of_subclasses_of_ref(); i++) {
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	465 enqueue_discovered_reflist(_discovered_refs[i], pending_list_addr);
bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	466 _discovered_refs[i].set_head(NULL);
bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	467 _discovered_refs[i].set_length(0);
0 a61af66fc99e Initial load duke parents: diff changeset	468 }
a61af66fc99e Initial load duke parents: diff changeset	469 }
a61af66fc99e Initial load duke parents: diff changeset	470 }
a61af66fc99e Initial load duke parents: diff changeset	471
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	472 void DiscoveredListIterator::load_ptrs(DEBUG_ONLY(bool allow_null_referent)) {
0 a61af66fc99e Initial load duke parents: diff changeset	473 _discovered_addr = java_lang_ref_Reference::discovered_addr(_ref);
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	474 oop discovered = java_lang_ref_Reference::discovered(_ref);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	475 assert(_discovered_addr && discovered->is_oop_or_null(),
0 a61af66fc99e Initial load duke parents: diff changeset	476 "discovered field is bad");
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	477 _next = discovered;
0 a61af66fc99e Initial load duke parents: diff changeset	478 _referent_addr = java_lang_ref_Reference::referent_addr(_ref);
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	479 _referent = java_lang_ref_Reference::referent(_ref);
0 a61af66fc99e Initial load duke parents: diff changeset	480 assert(Universe::heap()->is_in_reserved_or_null(_referent),
a61af66fc99e Initial load duke parents: diff changeset	481 "Wrong oop found in java.lang.Reference object");
a61af66fc99e Initial load duke parents: diff changeset	482 assert(allow_null_referent ?
a61af66fc99e Initial load duke parents: diff changeset	483 _referent->is_oop_or_null()
a61af66fc99e Initial load duke parents: diff changeset	484 : _referent->is_oop(),
a61af66fc99e Initial load duke parents: diff changeset	485 "bad referent");
a61af66fc99e Initial load duke parents: diff changeset	486 }
a61af66fc99e Initial load duke parents: diff changeset	487
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	488 void DiscoveredListIterator::remove() {
0 a61af66fc99e Initial load duke parents: diff changeset	489 assert(_ref->is_oop(), "Dropping a bad reference");
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	490 oop_store_raw(_discovered_addr, NULL);
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	491
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	492 // First _prev_next ref actually points into DiscoveredList (gross).
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	493 oop new_next;
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	494 if (_next == _ref) {
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	495 // At the end of the list, we should make _prev point to itself.
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	496 // If _ref is the first ref, then _prev_next will be in the DiscoveredList,
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	497 // and _prev will be NULL.
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	498 new_next = _prev;
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	499 } else {
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	500 new_next = _next;
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	501 }
17748 d60ecdb2773e 8031703: Missing post-barrier in ReferenceProcessor pliden parents: 17746 diff changeset	502 // Remove Reference object from discovered list. Note that G1 does not need a
d60ecdb2773e 8031703: Missing post-barrier in ReferenceProcessor pliden parents: 17746 diff changeset	503 // pre-barrier here because we know the Reference has already been found/marked,
d60ecdb2773e 8031703: Missing post-barrier in ReferenceProcessor pliden parents: 17746 diff changeset	504 // that's how it ended up in the discovered list in the first place.
d60ecdb2773e 8031703: Missing post-barrier in ReferenceProcessor pliden parents: 17746 diff changeset	505 oop_store_raw(_prev_next, new_next);
0 a61af66fc99e Initial load duke parents: diff changeset	506 NOT_PRODUCT(_removed++);
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	507 _refs_list.dec_length(1);
0 a61af66fc99e Initial load duke parents: diff changeset	508 }
a61af66fc99e Initial load duke parents: diff changeset	509
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	510 // Make the Reference object active again.
4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	511 void DiscoveredListIterator::make_active() {
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	512 // The pre barrier for G1 is probably just needed for the old
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	513 // reference processing behavior. Should we guard this with
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	514 // ReferenceProcessor::pending_list_uses_discovered_field() ?
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	515 if (UseG1GC) {
4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	516 HeapWord* next_addr = java_lang_ref_Reference::next_addr(_ref);
4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	517 if (UseCompressedOops) {
17746 a258f8cb530f 8029255: G1: Reference processing should not enqueue references on the shared SATB queue pliden parents: 12316 diff changeset	518 oopDesc::bs()->write_ref_field_pre((narrowOop*)next_addr, NULL);
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	519 } else {
17746 a258f8cb530f 8029255: G1: Reference processing should not enqueue references on the shared SATB queue pliden parents: 12316 diff changeset	520 oopDesc::bs()->write_ref_field_pre((oop*)next_addr, NULL);
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	521 }
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	522 }
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	523 java_lang_ref_Reference::set_next_raw(_ref, NULL);
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	524 }
4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	525
4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	526 void DiscoveredListIterator::clear_referent() {
4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	527 oop_store_raw(_referent_addr, NULL);
0 a61af66fc99e Initial load duke parents: diff changeset	528 }
a61af66fc99e Initial load duke parents: diff changeset	529
a61af66fc99e Initial load duke parents: diff changeset	530 // NOTE: process_phase*() are largely similar, and at a high level
a61af66fc99e Initial load duke parents: diff changeset	531 // merely iterate over the extant list applying a predicate to
a61af66fc99e Initial load duke parents: diff changeset	532 // each of its elements and possibly removing that element from the
a61af66fc99e Initial load duke parents: diff changeset	533 // list and applying some further closures to that element.
a61af66fc99e Initial load duke parents: diff changeset	534 // We should consider the possibility of replacing these
a61af66fc99e Initial load duke parents: diff changeset	535 // process_phase*() methods by abstracting them into
a61af66fc99e Initial load duke parents: diff changeset	536 // a single general iterator invocation that receives appropriate
a61af66fc99e Initial load duke parents: diff changeset	537 // closures that accomplish this work.
a61af66fc99e Initial load duke parents: diff changeset	538
a61af66fc99e Initial load duke parents: diff changeset	539 // (SoftReferences only) Traverse the list and remove any SoftReferences whose
a61af66fc99e Initial load duke parents: diff changeset	540 // referents are not alive, but that should be kept alive for policy reasons.
a61af66fc99e Initial load duke parents: diff changeset	541 // Keep alive the transitive closure of all such referents.
a61af66fc99e Initial load duke parents: diff changeset	542 void
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	543 ReferenceProcessor::process_phase1(DiscoveredList& refs_list,
0 a61af66fc99e Initial load duke parents: diff changeset	544 ReferencePolicy* policy,
a61af66fc99e Initial load duke parents: diff changeset	545 BoolObjectClosure* is_alive,
a61af66fc99e Initial load duke parents: diff changeset	546 OopClosure* keep_alive,
a61af66fc99e Initial load duke parents: diff changeset	547 VoidClosure* complete_gc) {
a61af66fc99e Initial load duke parents: diff changeset	548 assert(policy != NULL, "Must have a non-NULL policy");
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	549 DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
0 a61af66fc99e Initial load duke parents: diff changeset	550 // Decide which softly reachable refs should be kept alive.
a61af66fc99e Initial load duke parents: diff changeset	551 while (iter.has_next()) {
a61af66fc99e Initial load duke parents: diff changeset	552 iter.load_ptrs(DEBUG_ONLY(!discovery_is_atomic() /* allow_null_referent */));
a61af66fc99e Initial load duke parents: diff changeset	553 bool referent_is_dead = (iter.referent() != NULL) && !iter.is_referent_alive();
3992 d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	554 if (referent_is_dead &&
d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	555 !policy->should_clear_reference(iter.obj(), _soft_ref_timestamp_clock)) {
0 a61af66fc99e Initial load duke parents: diff changeset	556 if (TraceReferenceGC) {
a61af66fc99e Initial load duke parents: diff changeset	557 gclog_or_tty->print_cr("Dropping reference (" INTPTR_FORMAT ": %s" ") by policy",
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	558 (void *)iter.obj(), iter.obj()->klass()->internal_name());
0 a61af66fc99e Initial load duke parents: diff changeset	559 }
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	560 // Remove Reference object from list
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	561 iter.remove();
0 a61af66fc99e Initial load duke parents: diff changeset	562 // Make the Reference object active again
a61af66fc99e Initial load duke parents: diff changeset	563 iter.make_active();
a61af66fc99e Initial load duke parents: diff changeset	564 // keep the referent around
a61af66fc99e Initial load duke parents: diff changeset	565 iter.make_referent_alive();
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	566 iter.move_to_next();
0 a61af66fc99e Initial load duke parents: diff changeset	567 } else {
a61af66fc99e Initial load duke parents: diff changeset	568 iter.next();
a61af66fc99e Initial load duke parents: diff changeset	569 }
a61af66fc99e Initial load duke parents: diff changeset	570 }
a61af66fc99e Initial load duke parents: diff changeset	571 // Close the reachable set
a61af66fc99e Initial load duke parents: diff changeset	572 complete_gc->do_void();
a61af66fc99e Initial load duke parents: diff changeset	573 NOT_PRODUCT(
a61af66fc99e Initial load duke parents: diff changeset	574 if (PrintGCDetails && TraceReferenceGC) {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	575 gclog_or_tty->print_cr(" Dropped %d dead Refs out of %d "
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	576 "discovered Refs by policy, from list " INTPTR_FORMAT,
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	577 iter.removed(), iter.processed(), (address)refs_list.head());
0 a61af66fc99e Initial load duke parents: diff changeset	578 }
a61af66fc99e Initial load duke parents: diff changeset	579 )
a61af66fc99e Initial load duke parents: diff changeset	580 }
a61af66fc99e Initial load duke parents: diff changeset	581
a61af66fc99e Initial load duke parents: diff changeset	582 // Traverse the list and remove any Refs that are not active, or
a61af66fc99e Initial load duke parents: diff changeset	583 // whose referents are either alive or NULL.
a61af66fc99e Initial load duke parents: diff changeset	584 void
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	585 ReferenceProcessor::pp2_work(DiscoveredList& refs_list,
0 a61af66fc99e Initial load duke parents: diff changeset	586 BoolObjectClosure* is_alive,
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	587 OopClosure* keep_alive) {
0 a61af66fc99e Initial load duke parents: diff changeset	588 assert(discovery_is_atomic(), "Error");
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	589 DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
0 a61af66fc99e Initial load duke parents: diff changeset	590 while (iter.has_next()) {
a61af66fc99e Initial load duke parents: diff changeset	591 iter.load_ptrs(DEBUG_ONLY(false /* allow_null_referent */));
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	592 DEBUG_ONLY(oop next = java_lang_ref_Reference::next(iter.obj());)
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	593 assert(next == NULL, "Should not discover inactive Reference");
0 a61af66fc99e Initial load duke parents: diff changeset	594 if (iter.is_referent_alive()) {
a61af66fc99e Initial load duke parents: diff changeset	595 if (TraceReferenceGC) {
a61af66fc99e Initial load duke parents: diff changeset	596 gclog_or_tty->print_cr("Dropping strongly reachable reference (" INTPTR_FORMAT ": %s)",
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	597 (void *)iter.obj(), iter.obj()->klass()->internal_name());
0 a61af66fc99e Initial load duke parents: diff changeset	598 }
a61af66fc99e Initial load duke parents: diff changeset	599 // The referent is reachable after all.
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	600 // Remove Reference object from list.
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	601 iter.remove();
0 a61af66fc99e Initial load duke parents: diff changeset	602 // Update the referent pointer as necessary: Note that this
a61af66fc99e Initial load duke parents: diff changeset	603 // should not entail any recursive marking because the
a61af66fc99e Initial load duke parents: diff changeset	604 // referent must already have been traversed.
a61af66fc99e Initial load duke parents: diff changeset	605 iter.make_referent_alive();
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	606 iter.move_to_next();
0 a61af66fc99e Initial load duke parents: diff changeset	607 } else {
a61af66fc99e Initial load duke parents: diff changeset	608 iter.next();
a61af66fc99e Initial load duke parents: diff changeset	609 }
a61af66fc99e Initial load duke parents: diff changeset	610 }
a61af66fc99e Initial load duke parents: diff changeset	611 NOT_PRODUCT(
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	612 if (PrintGCDetails && TraceReferenceGC && (iter.processed() > 0)) {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	613 gclog_or_tty->print_cr(" Dropped %d active Refs out of %d "
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	614 "Refs in discovered list " INTPTR_FORMAT,
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	615 iter.removed(), iter.processed(), (address)refs_list.head());
0 a61af66fc99e Initial load duke parents: diff changeset	616 }
a61af66fc99e Initial load duke parents: diff changeset	617 )
a61af66fc99e Initial load duke parents: diff changeset	618 }
a61af66fc99e Initial load duke parents: diff changeset	619
a61af66fc99e Initial load duke parents: diff changeset	620 void
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	621 ReferenceProcessor::pp2_work_concurrent_discovery(DiscoveredList& refs_list,
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	622 BoolObjectClosure* is_alive,
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	623 OopClosure* keep_alive,
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	624 VoidClosure* complete_gc) {
0 a61af66fc99e Initial load duke parents: diff changeset	625 assert(!discovery_is_atomic(), "Error");
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	626 DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
0 a61af66fc99e Initial load duke parents: diff changeset	627 while (iter.has_next()) {
a61af66fc99e Initial load duke parents: diff changeset	628 iter.load_ptrs(DEBUG_ONLY(true /* allow_null_referent */));
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	629 HeapWord* next_addr = java_lang_ref_Reference::next_addr(iter.obj());
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	630 oop next = java_lang_ref_Reference::next(iter.obj());
0 a61af66fc99e Initial load duke parents: diff changeset	631 if ((iter.referent() == NULL \|\| iter.is_referent_alive() \|\|
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	632 next != NULL)) {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	633 assert(next->is_oop_or_null(), "bad next field");
0 a61af66fc99e Initial load duke parents: diff changeset	634 // Remove Reference object from list
a61af66fc99e Initial load duke parents: diff changeset	635 iter.remove();
a61af66fc99e Initial load duke parents: diff changeset	636 // Trace the cohorts
a61af66fc99e Initial load duke parents: diff changeset	637 iter.make_referent_alive();
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	638 if (UseCompressedOops) {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	639 keep_alive->do_oop((narrowOop*)next_addr);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	640 } else {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	641 keep_alive->do_oop((oop*)next_addr);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	642 }
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	643 iter.move_to_next();
0 a61af66fc99e Initial load duke parents: diff changeset	644 } else {
a61af66fc99e Initial load duke parents: diff changeset	645 iter.next();
a61af66fc99e Initial load duke parents: diff changeset	646 }
a61af66fc99e Initial load duke parents: diff changeset	647 }
a61af66fc99e Initial load duke parents: diff changeset	648 // Now close the newly reachable set
a61af66fc99e Initial load duke parents: diff changeset	649 complete_gc->do_void();
a61af66fc99e Initial load duke parents: diff changeset	650 NOT_PRODUCT(
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	651 if (PrintGCDetails && TraceReferenceGC && (iter.processed() > 0)) {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	652 gclog_or_tty->print_cr(" Dropped %d active Refs out of %d "
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	653 "Refs in discovered list " INTPTR_FORMAT,
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	654 iter.removed(), iter.processed(), (address)refs_list.head());
0 a61af66fc99e Initial load duke parents: diff changeset	655 }
a61af66fc99e Initial load duke parents: diff changeset	656 )
a61af66fc99e Initial load duke parents: diff changeset	657 }
a61af66fc99e Initial load duke parents: diff changeset	658
a61af66fc99e Initial load duke parents: diff changeset	659 // Traverse the list and process the referents, by either
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	660 // clearing them or keeping them (and their reachable
0 a61af66fc99e Initial load duke parents: diff changeset	661 // closure) alive.
a61af66fc99e Initial load duke parents: diff changeset	662 void
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	663 ReferenceProcessor::process_phase3(DiscoveredList& refs_list,
0 a61af66fc99e Initial load duke parents: diff changeset	664 bool clear_referent,
a61af66fc99e Initial load duke parents: diff changeset	665 BoolObjectClosure* is_alive,
a61af66fc99e Initial load duke parents: diff changeset	666 OopClosure* keep_alive,
a61af66fc99e Initial load duke parents: diff changeset	667 VoidClosure* complete_gc) {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	668 ResourceMark rm;
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	669 DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
0 a61af66fc99e Initial load duke parents: diff changeset	670 while (iter.has_next()) {
a61af66fc99e Initial load duke parents: diff changeset	671 iter.update_discovered();
a61af66fc99e Initial load duke parents: diff changeset	672 iter.load_ptrs(DEBUG_ONLY(false /* allow_null_referent */));
a61af66fc99e Initial load duke parents: diff changeset	673 if (clear_referent) {
a61af66fc99e Initial load duke parents: diff changeset	674 // NULL out referent pointer
a61af66fc99e Initial load duke parents: diff changeset	675 iter.clear_referent();
a61af66fc99e Initial load duke parents: diff changeset	676 } else {
a61af66fc99e Initial load duke parents: diff changeset	677 // keep the referent around
a61af66fc99e Initial load duke parents: diff changeset	678 iter.make_referent_alive();
a61af66fc99e Initial load duke parents: diff changeset	679 }
a61af66fc99e Initial load duke parents: diff changeset	680 if (TraceReferenceGC) {
a61af66fc99e Initial load duke parents: diff changeset	681 gclog_or_tty->print_cr("Adding %sreference (" INTPTR_FORMAT ": %s) as pending",
a61af66fc99e Initial load duke parents: diff changeset	682 clear_referent ? "cleared " : "",
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	683 (void *)iter.obj(), iter.obj()->klass()->internal_name());
0 a61af66fc99e Initial load duke parents: diff changeset	684 }
a61af66fc99e Initial load duke parents: diff changeset	685 assert(iter.obj()->is_oop(UseConcMarkSweepGC), "Adding a bad reference");
a61af66fc99e Initial load duke parents: diff changeset	686 iter.next();
a61af66fc99e Initial load duke parents: diff changeset	687 }
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	688 // Remember to update the next pointer of the last ref.
0 a61af66fc99e Initial load duke parents: diff changeset	689 iter.update_discovered();
a61af66fc99e Initial load duke parents: diff changeset	690 // Close the reachable set
a61af66fc99e Initial load duke parents: diff changeset	691 complete_gc->do_void();
a61af66fc99e Initial load duke parents: diff changeset	692 }
a61af66fc99e Initial load duke parents: diff changeset	693
a61af66fc99e Initial load duke parents: diff changeset	694 void
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	695 ReferenceProcessor::clear_discovered_references(DiscoveredList& refs_list) {
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	696 oop obj = NULL;
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	697 oop next = refs_list.head();
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	698 while (next != obj) {
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	699 obj = next;
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	700 next = java_lang_ref_Reference::discovered(obj);
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	701 java_lang_ref_Reference::set_discovered_raw(obj, NULL);
0 a61af66fc99e Initial load duke parents: diff changeset	702 }
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	703 refs_list.set_head(NULL);
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	704 refs_list.set_length(0);
0 a61af66fc99e Initial load duke parents: diff changeset	705 }
a61af66fc99e Initial load duke parents: diff changeset	706
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	707 void
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	708 ReferenceProcessor::abandon_partial_discovered_list(DiscoveredList& refs_list) {
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	709 clear_discovered_references(refs_list);
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	710 }
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	711
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	712 void ReferenceProcessor::abandon_partial_discovery() {
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	713 // loop over the lists
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	714 for (uint i = 0; i < _max_num_q * number_of_subclasses_of_ref(); i++) {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	715 if (TraceReferenceGC && PrintGCDetails && ((i % _max_num_q) == 0)) {
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	716 gclog_or_tty->print_cr("\nAbandoning %s discovered list", list_name(i));
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	717 }
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	718 abandon_partial_discovered_list(_discovered_refs[i]);
0 a61af66fc99e Initial load duke parents: diff changeset	719 }
a61af66fc99e Initial load duke parents: diff changeset	720 }
a61af66fc99e Initial load duke parents: diff changeset	721
a61af66fc99e Initial load duke parents: diff changeset	722 class RefProcPhase1Task: public AbstractRefProcTaskExecutor::ProcessTask {
a61af66fc99e Initial load duke parents: diff changeset	723 public:
a61af66fc99e Initial load duke parents: diff changeset	724 RefProcPhase1Task(ReferenceProcessor& ref_processor,
a61af66fc99e Initial load duke parents: diff changeset	725 DiscoveredList refs_lists[],
a61af66fc99e Initial load duke parents: diff changeset	726 ReferencePolicy* policy,
a61af66fc99e Initial load duke parents: diff changeset	727 bool marks_oops_alive)
a61af66fc99e Initial load duke parents: diff changeset	728 : ProcessTask(ref_processor, refs_lists, marks_oops_alive),
a61af66fc99e Initial load duke parents: diff changeset	729 _policy(policy)
a61af66fc99e Initial load duke parents: diff changeset	730 { }
a61af66fc99e Initial load duke parents: diff changeset	731 virtual void work(unsigned int i, BoolObjectClosure& is_alive,
a61af66fc99e Initial load duke parents: diff changeset	732 OopClosure& keep_alive,
a61af66fc99e Initial load duke parents: diff changeset	733 VoidClosure& complete_gc)
a61af66fc99e Initial load duke parents: diff changeset	734 {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	735 Thread* thr = Thread::current();
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	736 int refs_list_index = ((WorkerThread*)thr)->id();
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	737 _ref_processor.process_phase1(_refs_lists[refs_list_index], _policy,
0 a61af66fc99e Initial load duke parents: diff changeset	738 &is_alive, &keep_alive, &complete_gc);
a61af66fc99e Initial load duke parents: diff changeset	739 }
a61af66fc99e Initial load duke parents: diff changeset	740 private:
a61af66fc99e Initial load duke parents: diff changeset	741 ReferencePolicy* _policy;
a61af66fc99e Initial load duke parents: diff changeset	742 };
a61af66fc99e Initial load duke parents: diff changeset	743
a61af66fc99e Initial load duke parents: diff changeset	744 class RefProcPhase2Task: public AbstractRefProcTaskExecutor::ProcessTask {
a61af66fc99e Initial load duke parents: diff changeset	745 public:
a61af66fc99e Initial load duke parents: diff changeset	746 RefProcPhase2Task(ReferenceProcessor& ref_processor,
a61af66fc99e Initial load duke parents: diff changeset	747 DiscoveredList refs_lists[],
a61af66fc99e Initial load duke parents: diff changeset	748 bool marks_oops_alive)
a61af66fc99e Initial load duke parents: diff changeset	749 : ProcessTask(ref_processor, refs_lists, marks_oops_alive)
a61af66fc99e Initial load duke parents: diff changeset	750 { }
a61af66fc99e Initial load duke parents: diff changeset	751 virtual void work(unsigned int i, BoolObjectClosure& is_alive,
a61af66fc99e Initial load duke parents: diff changeset	752 OopClosure& keep_alive,
a61af66fc99e Initial load duke parents: diff changeset	753 VoidClosure& complete_gc)
a61af66fc99e Initial load duke parents: diff changeset	754 {
a61af66fc99e Initial load duke parents: diff changeset	755 _ref_processor.process_phase2(_refs_lists[i],
a61af66fc99e Initial load duke parents: diff changeset	756 &is_alive, &keep_alive, &complete_gc);
a61af66fc99e Initial load duke parents: diff changeset	757 }
a61af66fc99e Initial load duke parents: diff changeset	758 };
a61af66fc99e Initial load duke parents: diff changeset	759
a61af66fc99e Initial load duke parents: diff changeset	760 class RefProcPhase3Task: public AbstractRefProcTaskExecutor::ProcessTask {
a61af66fc99e Initial load duke parents: diff changeset	761 public:
a61af66fc99e Initial load duke parents: diff changeset	762 RefProcPhase3Task(ReferenceProcessor& ref_processor,
a61af66fc99e Initial load duke parents: diff changeset	763 DiscoveredList refs_lists[],
a61af66fc99e Initial load duke parents: diff changeset	764 bool clear_referent,
a61af66fc99e Initial load duke parents: diff changeset	765 bool marks_oops_alive)
a61af66fc99e Initial load duke parents: diff changeset	766 : ProcessTask(ref_processor, refs_lists, marks_oops_alive),
a61af66fc99e Initial load duke parents: diff changeset	767 _clear_referent(clear_referent)
a61af66fc99e Initial load duke parents: diff changeset	768 { }
a61af66fc99e Initial load duke parents: diff changeset	769 virtual void work(unsigned int i, BoolObjectClosure& is_alive,
a61af66fc99e Initial load duke parents: diff changeset	770 OopClosure& keep_alive,
a61af66fc99e Initial load duke parents: diff changeset	771 VoidClosure& complete_gc)
a61af66fc99e Initial load duke parents: diff changeset	772 {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	773 // Don't use "refs_list_index" calculated in this way because
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	774 // balance_queues() has moved the Ref's into the first n queues.
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	775 // Thread* thr = Thread::current();
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	776 // int refs_list_index = ((WorkerThread*)thr)->id();
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	777 // _ref_processor.process_phase3(_refs_lists[refs_list_index], _clear_referent,
0 a61af66fc99e Initial load duke parents: diff changeset	778 _ref_processor.process_phase3(_refs_lists[i], _clear_referent,
a61af66fc99e Initial load duke parents: diff changeset	779 &is_alive, &keep_alive, &complete_gc);
a61af66fc99e Initial load duke parents: diff changeset	780 }
a61af66fc99e Initial load duke parents: diff changeset	781 private:
a61af66fc99e Initial load duke parents: diff changeset	782 bool _clear_referent;
a61af66fc99e Initial load duke parents: diff changeset	783 };
a61af66fc99e Initial load duke parents: diff changeset	784
a61af66fc99e Initial load duke parents: diff changeset	785 // Balances reference queues.
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	786 // Move entries from all queues[0, 1, ..., _max_num_q-1] to
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	787 // queues[0, 1, ..., _num_q-1] because only the first _num_q
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	788 // corresponding to the active workers will be processed.
0 a61af66fc99e Initial load duke parents: diff changeset	789 void ReferenceProcessor::balance_queues(DiscoveredList ref_lists[])
a61af66fc99e Initial load duke parents: diff changeset	790 {
a61af66fc99e Initial load duke parents: diff changeset	791 // calculate total length
a61af66fc99e Initial load duke parents: diff changeset	792 size_t total_refs = 0;
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	793 if (TraceReferenceGC && PrintGCDetails) {
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	794 gclog_or_tty->print_cr("\nBalance ref_lists ");
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	795 }
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	796
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	797 for (uint i = 0; i < _max_num_q; ++i) {
0 a61af66fc99e Initial load duke parents: diff changeset	798 total_refs += ref_lists[i].length();
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	799 if (TraceReferenceGC && PrintGCDetails) {
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	800 gclog_or_tty->print("%d ", ref_lists[i].length());
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	801 }
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	802 }
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	803 if (TraceReferenceGC && PrintGCDetails) {
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	804 gclog_or_tty->print_cr(" = %d", total_refs);
0 a61af66fc99e Initial load duke parents: diff changeset	805 }
a61af66fc99e Initial load duke parents: diff changeset	806 size_t avg_refs = total_refs / _num_q + 1;
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	807 uint to_idx = 0;
441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	808 for (uint from_idx = 0; from_idx < _max_num_q; from_idx++) {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	809 bool move_all = false;
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	810 if (from_idx >= _num_q) {
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	811 move_all = ref_lists[from_idx].length() > 0;
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	812 }
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	813 while ((ref_lists[from_idx].length() > avg_refs) \|\|
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	814 move_all) {
0 a61af66fc99e Initial load duke parents: diff changeset	815 assert(to_idx < _num_q, "Sanity Check!");
a61af66fc99e Initial load duke parents: diff changeset	816 if (ref_lists[to_idx].length() < avg_refs) {
a61af66fc99e Initial load duke parents: diff changeset	817 // move superfluous refs
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	818 size_t refs_to_move;
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	819 // Move all the Ref's if the from queue will not be processed.
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	820 if (move_all) {
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	821 refs_to_move = MIN2(ref_lists[from_idx].length(),
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	822 avg_refs - ref_lists[to_idx].length());
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	823 } else {
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	824 refs_to_move = MIN2(ref_lists[from_idx].length() - avg_refs,
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	825 avg_refs - ref_lists[to_idx].length());
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	826 }
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	827
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	828 assert(refs_to_move > 0, "otherwise the code below will fail");
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	829
0 a61af66fc99e Initial load duke parents: diff changeset	830 oop move_head = ref_lists[from_idx].head();
a61af66fc99e Initial load duke parents: diff changeset	831 oop move_tail = move_head;
a61af66fc99e Initial load duke parents: diff changeset	832 oop new_head = move_head;
a61af66fc99e Initial load duke parents: diff changeset	833 // find an element to split the list on
a61af66fc99e Initial load duke parents: diff changeset	834 for (size_t j = 0; j < refs_to_move; ++j) {
a61af66fc99e Initial load duke parents: diff changeset	835 move_tail = new_head;
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	836 new_head = java_lang_ref_Reference::discovered(new_head);
0 a61af66fc99e Initial load duke parents: diff changeset	837 }
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	838
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	839 // Add the chain to the to list.
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	840 if (ref_lists[to_idx].head() == NULL) {
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	841 // to list is empty. Make a loop at the end.
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	842 java_lang_ref_Reference::set_discovered_raw(move_tail, move_tail);
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	843 } else {
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	844 java_lang_ref_Reference::set_discovered_raw(move_tail, ref_lists[to_idx].head());
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	845 }
0 a61af66fc99e Initial load duke parents: diff changeset	846 ref_lists[to_idx].set_head(move_head);
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	847 ref_lists[to_idx].inc_length(refs_to_move);
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	848
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	849 // Remove the chain from the from list.
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	850 if (move_tail == new_head) {
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	851 // We found the end of the from list.
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	852 ref_lists[from_idx].set_head(NULL);
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	853 } else {
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	854 ref_lists[from_idx].set_head(new_head);
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	855 }
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	856 ref_lists[from_idx].dec_length(refs_to_move);
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	857 if (ref_lists[from_idx].length() == 0) {
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	858 break;
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	859 }
0 a61af66fc99e Initial load duke parents: diff changeset	860 } else {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	861 to_idx = (to_idx + 1) % _num_q;
0 a61af66fc99e Initial load duke parents: diff changeset	862 }
a61af66fc99e Initial load duke parents: diff changeset	863 }
a61af66fc99e Initial load duke parents: diff changeset	864 }
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	865 #ifdef ASSERT
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	866 size_t balanced_total_refs = 0;
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	867 for (uint i = 0; i < _max_num_q; ++i) {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	868 balanced_total_refs += ref_lists[i].length();
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	869 if (TraceReferenceGC && PrintGCDetails) {
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	870 gclog_or_tty->print("%d ", ref_lists[i].length());
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	871 }
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	872 }
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	873 if (TraceReferenceGC && PrintGCDetails) {
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	874 gclog_or_tty->print_cr(" = %d", balanced_total_refs);
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	875 gclog_or_tty->flush();
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	876 }
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	877 assert(total_refs == balanced_total_refs, "Balancing was incomplete");
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	878 #endif
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	879 }
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	880
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	881 void ReferenceProcessor::balance_all_queues() {
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	882 balance_queues(_discoveredSoftRefs);
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	883 balance_queues(_discoveredWeakRefs);
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	884 balance_queues(_discoveredFinalRefs);
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	885 balance_queues(_discoveredPhantomRefs);
0 a61af66fc99e Initial load duke parents: diff changeset	886 }
a61af66fc99e Initial load duke parents: diff changeset	887
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	888 size_t
0 a61af66fc99e Initial load duke parents: diff changeset	889 ReferenceProcessor::process_discovered_reflist(
a61af66fc99e Initial load duke parents: diff changeset	890 DiscoveredList refs_lists[],
a61af66fc99e Initial load duke parents: diff changeset	891 ReferencePolicy* policy,
a61af66fc99e Initial load duke parents: diff changeset	892 bool clear_referent,
a61af66fc99e Initial load duke parents: diff changeset	893 BoolObjectClosure* is_alive,
a61af66fc99e Initial load duke parents: diff changeset	894 OopClosure* keep_alive,
a61af66fc99e Initial load duke parents: diff changeset	895 VoidClosure* complete_gc,
a61af66fc99e Initial load duke parents: diff changeset	896 AbstractRefProcTaskExecutor* task_executor)
a61af66fc99e Initial load duke parents: diff changeset	897 {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	898 bool mt_processing = task_executor != NULL && _processing_is_mt;
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	899 // If discovery used MT and a dynamic number of GC threads, then
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	900 // the queues must be balanced for correctness if fewer than the
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	901 // maximum number of queues were used. The number of queue used
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	902 // during discovery may be different than the number to be used
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	903 // for processing so don't depend of _num_q < _max_num_q as part
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	904 // of the test.
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	905 bool must_balance = _discovery_is_mt;
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	906
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	907 if ((mt_processing && ParallelRefProcBalancingEnabled) \|\|
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	908 must_balance) {
0 a61af66fc99e Initial load duke parents: diff changeset	909 balance_queues(refs_lists);
a61af66fc99e Initial load duke parents: diff changeset	910 }
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	911
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	912 size_t total_list_count = total_count(refs_lists);
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	913
0 a61af66fc99e Initial load duke parents: diff changeset	914 if (PrintReferenceGC && PrintGCDetails) {
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	915 gclog_or_tty->print(", %u refs", total_list_count);
0 a61af66fc99e Initial load duke parents: diff changeset	916 }
a61af66fc99e Initial load duke parents: diff changeset	917
a61af66fc99e Initial load duke parents: diff changeset	918 // Phase 1 (soft refs only):
a61af66fc99e Initial load duke parents: diff changeset	919 // . Traverse the list and remove any SoftReferences whose
a61af66fc99e Initial load duke parents: diff changeset	920 // referents are not alive, but that should be kept alive for
a61af66fc99e Initial load duke parents: diff changeset	921 // policy reasons. Keep alive the transitive closure of all
a61af66fc99e Initial load duke parents: diff changeset	922 // such referents.
a61af66fc99e Initial load duke parents: diff changeset	923 if (policy != NULL) {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	924 if (mt_processing) {
0 a61af66fc99e Initial load duke parents: diff changeset	925 RefProcPhase1Task phase1(this, refs_lists, policy, true /marks_oops_alive*/);
a61af66fc99e Initial load duke parents: diff changeset	926 task_executor->execute(phase1);
a61af66fc99e Initial load duke parents: diff changeset	927 } else {
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	928 for (uint i = 0; i < _max_num_q; i++) {
0 a61af66fc99e Initial load duke parents: diff changeset	929 process_phase1(refs_lists[i], policy,
a61af66fc99e Initial load duke parents: diff changeset	930 is_alive, keep_alive, complete_gc);
a61af66fc99e Initial load duke parents: diff changeset	931 }
a61af66fc99e Initial load duke parents: diff changeset	932 }
a61af66fc99e Initial load duke parents: diff changeset	933 } else { // policy == NULL
a61af66fc99e Initial load duke parents: diff changeset	934 assert(refs_lists != _discoveredSoftRefs,
a61af66fc99e Initial load duke parents: diff changeset	935 "Policy must be specified for soft references.");
a61af66fc99e Initial load duke parents: diff changeset	936 }
a61af66fc99e Initial load duke parents: diff changeset	937
a61af66fc99e Initial load duke parents: diff changeset	938 // Phase 2:
a61af66fc99e Initial load duke parents: diff changeset	939 // . Traverse the list and remove any refs whose referents are alive.
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	940 if (mt_processing) {
0 a61af66fc99e Initial load duke parents: diff changeset	941 RefProcPhase2Task phase2(this, refs_lists, !discovery_is_atomic() /marks_oops_alive*/);
a61af66fc99e Initial load duke parents: diff changeset	942 task_executor->execute(phase2);
a61af66fc99e Initial load duke parents: diff changeset	943 } else {
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	944 for (uint i = 0; i < _max_num_q; i++) {
0 a61af66fc99e Initial load duke parents: diff changeset	945 process_phase2(refs_lists[i], is_alive, keep_alive, complete_gc);
a61af66fc99e Initial load duke parents: diff changeset	946 }
a61af66fc99e Initial load duke parents: diff changeset	947 }
a61af66fc99e Initial load duke parents: diff changeset	948
a61af66fc99e Initial load duke parents: diff changeset	949 // Phase 3:
a61af66fc99e Initial load duke parents: diff changeset	950 // . Traverse the list and process referents as appropriate.
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	951 if (mt_processing) {
0 a61af66fc99e Initial load duke parents: diff changeset	952 RefProcPhase3Task phase3(this, refs_lists, clear_referent, true /marks_oops_alive*/);
a61af66fc99e Initial load duke parents: diff changeset	953 task_executor->execute(phase3);
a61af66fc99e Initial load duke parents: diff changeset	954 } else {
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	955 for (uint i = 0; i < _max_num_q; i++) {
0 a61af66fc99e Initial load duke parents: diff changeset	956 process_phase3(refs_lists[i], clear_referent,
a61af66fc99e Initial load duke parents: diff changeset	957 is_alive, keep_alive, complete_gc);
a61af66fc99e Initial load duke parents: diff changeset	958 }
a61af66fc99e Initial load duke parents: diff changeset	959 }
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	960
f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	961 return total_list_count;
0 a61af66fc99e Initial load duke parents: diff changeset	962 }
a61af66fc99e Initial load duke parents: diff changeset	963
a61af66fc99e Initial load duke parents: diff changeset	964 void ReferenceProcessor::clean_up_discovered_references() {
a61af66fc99e Initial load duke parents: diff changeset	965 // loop over the lists
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	966 for (uint i = 0; i < _max_num_q * number_of_subclasses_of_ref(); i++) {
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	967 if (TraceReferenceGC && PrintGCDetails && ((i % _max_num_q) == 0)) {
0 a61af66fc99e Initial load duke parents: diff changeset	968 gclog_or_tty->print_cr(
a61af66fc99e Initial load duke parents: diff changeset	969 "\nScrubbing %s discovered list of Null referents",
a61af66fc99e Initial load duke parents: diff changeset	970 list_name(i));
a61af66fc99e Initial load duke parents: diff changeset	971 }
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	972 clean_up_discovered_reflist(_discovered_refs[i]);
0 a61af66fc99e Initial load duke parents: diff changeset	973 }
a61af66fc99e Initial load duke parents: diff changeset	974 }
a61af66fc99e Initial load duke parents: diff changeset	975
a61af66fc99e Initial load duke parents: diff changeset	976 void ReferenceProcessor::clean_up_discovered_reflist(DiscoveredList& refs_list) {
a61af66fc99e Initial load duke parents: diff changeset	977 assert(!discovery_is_atomic(), "Else why call this method?");
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	978 DiscoveredListIterator iter(refs_list, NULL, NULL);
0 a61af66fc99e Initial load duke parents: diff changeset	979 while (iter.has_next()) {
a61af66fc99e Initial load duke parents: diff changeset	980 iter.load_ptrs(DEBUG_ONLY(true /* allow_null_referent */));
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	981 oop next = java_lang_ref_Reference::next(iter.obj());
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	982 assert(next->is_oop_or_null(), "bad next field");
0 a61af66fc99e Initial load duke parents: diff changeset	983 // If referent has been cleared or Reference is not active,
a61af66fc99e Initial load duke parents: diff changeset	984 // drop it.
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	985 if (iter.referent() == NULL \|\| next != NULL) {
0 a61af66fc99e Initial load duke parents: diff changeset	986 debug_only(
a61af66fc99e Initial load duke parents: diff changeset	987 if (PrintGCDetails && TraceReferenceGC) {
a61af66fc99e Initial load duke parents: diff changeset	988 gclog_or_tty->print_cr("clean_up_discovered_list: Dropping Reference: "
a61af66fc99e Initial load duke parents: diff changeset	989 INTPTR_FORMAT " with next field: " INTPTR_FORMAT
a61af66fc99e Initial load duke parents: diff changeset	990 " and referent: " INTPTR_FORMAT,
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	991 (void )iter.obj(), (void )next, (void *)iter.referent());
0 a61af66fc99e Initial load duke parents: diff changeset	992 }
a61af66fc99e Initial load duke parents: diff changeset	993 )
a61af66fc99e Initial load duke parents: diff changeset	994 // Remove Reference object from list
a61af66fc99e Initial load duke parents: diff changeset	995 iter.remove();
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	996 iter.move_to_next();
0 a61af66fc99e Initial load duke parents: diff changeset	997 } else {
a61af66fc99e Initial load duke parents: diff changeset	998 iter.next();
a61af66fc99e Initial load duke parents: diff changeset	999 }
a61af66fc99e Initial load duke parents: diff changeset	1000 }
a61af66fc99e Initial load duke parents: diff changeset	1001 NOT_PRODUCT(
a61af66fc99e Initial load duke parents: diff changeset	1002 if (PrintGCDetails && TraceReferenceGC) {
a61af66fc99e Initial load duke parents: diff changeset	1003 gclog_or_tty->print(
a61af66fc99e Initial load duke parents: diff changeset	1004 " Removed %d Refs with NULL referents out of %d discovered Refs",
a61af66fc99e Initial load duke parents: diff changeset	1005 iter.removed(), iter.processed());
a61af66fc99e Initial load duke parents: diff changeset	1006 }
a61af66fc99e Initial load duke parents: diff changeset	1007 )
a61af66fc99e Initial load duke parents: diff changeset	1008 }
a61af66fc99e Initial load duke parents: diff changeset	1009
a61af66fc99e Initial load duke parents: diff changeset	1010 inline DiscoveredList* ReferenceProcessor::get_discovered_list(ReferenceType rt) {
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	1011 uint id = 0;
0 a61af66fc99e Initial load duke parents: diff changeset	1012 // Determine the queue index to use for this object.
a61af66fc99e Initial load duke parents: diff changeset	1013 if (_discovery_is_mt) {
a61af66fc99e Initial load duke parents: diff changeset	1014 // During a multi-threaded discovery phase,
a61af66fc99e Initial load duke parents: diff changeset	1015 // each thread saves to its "own" list.
a61af66fc99e Initial load duke parents: diff changeset	1016 Thread* thr = Thread::current();
1974 fd1d227ef1b9 6983204: G1: Nightly test nsk/regression/b4958615 failing with +ExplicitGCInvokesConcurrent johnc parents: 1972 diff changeset	1017 id = thr->as_Worker_thread()->id();
0 a61af66fc99e Initial load duke parents: diff changeset	1018 } else {
a61af66fc99e Initial load duke parents: diff changeset	1019 // single-threaded discovery, we save in round-robin
a61af66fc99e Initial load duke parents: diff changeset	1020 // fashion to each of the lists.
a61af66fc99e Initial load duke parents: diff changeset	1021 if (_processing_is_mt) {
a61af66fc99e Initial load duke parents: diff changeset	1022 id = next_id();
a61af66fc99e Initial load duke parents: diff changeset	1023 }
a61af66fc99e Initial load duke parents: diff changeset	1024 }
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	1025 assert(0 <= id && id < _max_num_q, "Id is out-of-bounds (call Freud?)");
0 a61af66fc99e Initial load duke parents: diff changeset	1026
a61af66fc99e Initial load duke parents: diff changeset	1027 // Get the discovered queue to which we will add
a61af66fc99e Initial load duke parents: diff changeset	1028 DiscoveredList* list = NULL;
a61af66fc99e Initial load duke parents: diff changeset	1029 switch (rt) {
a61af66fc99e Initial load duke parents: diff changeset	1030 case REF_OTHER:
a61af66fc99e Initial load duke parents: diff changeset	1031 // Unknown reference type, no special treatment
a61af66fc99e Initial load duke parents: diff changeset	1032 break;
a61af66fc99e Initial load duke parents: diff changeset	1033 case REF_SOFT:
a61af66fc99e Initial load duke parents: diff changeset	1034 list = &_discoveredSoftRefs[id];
a61af66fc99e Initial load duke parents: diff changeset	1035 break;
a61af66fc99e Initial load duke parents: diff changeset	1036 case REF_WEAK:
a61af66fc99e Initial load duke parents: diff changeset	1037 list = &_discoveredWeakRefs[id];
a61af66fc99e Initial load duke parents: diff changeset	1038 break;
a61af66fc99e Initial load duke parents: diff changeset	1039 case REF_FINAL:
a61af66fc99e Initial load duke parents: diff changeset	1040 list = &_discoveredFinalRefs[id];
a61af66fc99e Initial load duke parents: diff changeset	1041 break;
a61af66fc99e Initial load duke parents: diff changeset	1042 case REF_PHANTOM:
a61af66fc99e Initial load duke parents: diff changeset	1043 list = &_discoveredPhantomRefs[id];
a61af66fc99e Initial load duke parents: diff changeset	1044 break;
a61af66fc99e Initial load duke parents: diff changeset	1045 case REF_NONE:
6735 aed758eda82a 7195833: NPG: Rename instanceClassLoaderKlass, instanceRefKlass and instanceMirrorKlass coleenp parents: 6725 diff changeset	1046 // we should not reach here if we are an InstanceRefKlass
0 a61af66fc99e Initial load duke parents: diff changeset	1047 default:
a61af66fc99e Initial load duke parents: diff changeset	1048 ShouldNotReachHere();
a61af66fc99e Initial load duke parents: diff changeset	1049 }
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	1050 if (TraceReferenceGC && PrintGCDetails) {
1974 fd1d227ef1b9 6983204: G1: Nightly test nsk/regression/b4958615 failing with +ExplicitGCInvokesConcurrent johnc parents: 1972 diff changeset	1051 gclog_or_tty->print_cr("Thread %d gets list " INTPTR_FORMAT, id, list);
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	1052 }
0 a61af66fc99e Initial load duke parents: diff changeset	1053 return list;
a61af66fc99e Initial load duke parents: diff changeset	1054 }
a61af66fc99e Initial load duke parents: diff changeset	1055
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1056 inline void
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1057 ReferenceProcessor::add_to_discovered_list_mt(DiscoveredList& refs_list,
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1058 oop obj,
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1059 HeapWord* discovered_addr) {
0 a61af66fc99e Initial load duke parents: diff changeset	1060 assert(_discovery_is_mt, "!_discovery_is_mt should have been handled by caller");
a61af66fc99e Initial load duke parents: diff changeset	1061 // First we must make sure this object is only enqueued once. CAS in a non null
a61af66fc99e Initial load duke parents: diff changeset	1062 // discovered_addr.
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	1063 oop current_head = refs_list.head();
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	1064 // The last ref must have its discovered field pointing to itself.
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	1065 oop next_discovered = (current_head != NULL) ? current_head : obj;
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	1066
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	1067 oop retest = oopDesc::atomic_compare_exchange_oop(next_discovered, discovered_addr,
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1068 NULL);
0 a61af66fc99e Initial load duke parents: diff changeset	1069 if (retest == NULL) {
a61af66fc99e Initial load duke parents: diff changeset	1070 // This thread just won the right to enqueue the object.
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1071 // We have separate lists for enqueueing, so no synchronization
0 a61af66fc99e Initial load duke parents: diff changeset	1072 // is necessary.
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1073 refs_list.set_head(obj);
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1074 refs_list.inc_length(1);
1974 fd1d227ef1b9 6983204: G1: Nightly test nsk/regression/b4958615 failing with +ExplicitGCInvokesConcurrent johnc parents: 1972 diff changeset	1075
fd1d227ef1b9 6983204: G1: Nightly test nsk/regression/b4958615 failing with +ExplicitGCInvokesConcurrent johnc parents: 1972 diff changeset	1076 if (TraceReferenceGC) {
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1077 gclog_or_tty->print_cr("Discovered reference (mt) (" INTPTR_FORMAT ": %s)",
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	1078 (void *)obj, obj->klass()->internal_name());
1974 fd1d227ef1b9 6983204: G1: Nightly test nsk/regression/b4958615 failing with +ExplicitGCInvokesConcurrent johnc parents: 1972 diff changeset	1079 }
0 a61af66fc99e Initial load duke parents: diff changeset	1080 } else {
a61af66fc99e Initial load duke parents: diff changeset	1081 // If retest was non NULL, another thread beat us to it:
a61af66fc99e Initial load duke parents: diff changeset	1082 // The reference has already been discovered...
a61af66fc99e Initial load duke parents: diff changeset	1083 if (TraceReferenceGC) {
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1084 gclog_or_tty->print_cr("Already discovered reference (" INTPTR_FORMAT ": %s)",
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	1085 (void *)obj, obj->klass()->internal_name());
0 a61af66fc99e Initial load duke parents: diff changeset	1086 }
a61af66fc99e Initial load duke parents: diff changeset	1087 }
a61af66fc99e Initial load duke parents: diff changeset	1088 }
a61af66fc99e Initial load duke parents: diff changeset	1089
1995 8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1090 #ifndef PRODUCT
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1091 // Non-atomic (i.e. concurrent) discovery might allow us
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1092 // to observe j.l.References with NULL referents, being those
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1093 // cleared concurrently by mutators during (or after) discovery.
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1094 void ReferenceProcessor::verify_referent(oop obj) {
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1095 bool da = discovery_is_atomic();
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1096 oop referent = java_lang_ref_Reference::referent(obj);
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1097 assert(da ? referent->is_oop() : referent->is_oop_or_null(),
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1098 err_msg("Bad referent " INTPTR_FORMAT " found in Reference "
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1099 INTPTR_FORMAT " during %satomic discovery ",
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	1100 (void )referent, (void )obj, da ? "" : "non-"));
1995 8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1101 }
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1102 #endif
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1103
0 a61af66fc99e Initial load duke parents: diff changeset	1104 // We mention two of several possible choices here:
a61af66fc99e Initial load duke parents: diff changeset	1105 // #0: if the reference object is not in the "originating generation"
a61af66fc99e Initial load duke parents: diff changeset	1106 // (or part of the heap being collected, indicated by our "span"
a61af66fc99e Initial load duke parents: diff changeset	1107 // we don't treat it specially (i.e. we scan it as we would
a61af66fc99e Initial load duke parents: diff changeset	1108 // a normal oop, treating its references as strong references).
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1109 // This means that references can't be discovered unless their
0 a61af66fc99e Initial load duke parents: diff changeset	1110 // referent is also in the same span. This is the simplest,
a61af66fc99e Initial load duke parents: diff changeset	1111 // most "local" and most conservative approach, albeit one
a61af66fc99e Initial load duke parents: diff changeset	1112 // that may cause weak references to be enqueued least promptly.
a61af66fc99e Initial load duke parents: diff changeset	1113 // We call this choice the "ReferenceBasedDiscovery" policy.
a61af66fc99e Initial load duke parents: diff changeset	1114 // #1: the reference object may be in any generation (span), but if
a61af66fc99e Initial load duke parents: diff changeset	1115 // the referent is in the generation (span) being currently collected
a61af66fc99e Initial load duke parents: diff changeset	1116 // then we can discover the reference object, provided
a61af66fc99e Initial load duke parents: diff changeset	1117 // the object has not already been discovered by
a61af66fc99e Initial load duke parents: diff changeset	1118 // a different concurrently running collector (as may be the
a61af66fc99e Initial load duke parents: diff changeset	1119 // case, for instance, if the reference object is in CMS and
a61af66fc99e Initial load duke parents: diff changeset	1120 // the referent in DefNewGeneration), and provided the processing
a61af66fc99e Initial load duke parents: diff changeset	1121 // of this reference object by the current collector will
a61af66fc99e Initial load duke parents: diff changeset	1122 // appear atomic to every other collector in the system.
a61af66fc99e Initial load duke parents: diff changeset	1123 // (Thus, for instance, a concurrent collector may not
a61af66fc99e Initial load duke parents: diff changeset	1124 // discover references in other generations even if the
a61af66fc99e Initial load duke parents: diff changeset	1125 // referent is in its own generation). This policy may,
a61af66fc99e Initial load duke parents: diff changeset	1126 // in certain cases, enqueue references somewhat sooner than
a61af66fc99e Initial load duke parents: diff changeset	1127 // might Policy #0 above, but at marginally increased cost
a61af66fc99e Initial load duke parents: diff changeset	1128 // and complexity in processing these references.
a61af66fc99e Initial load duke parents: diff changeset	1129 // We call this choice the "RefeferentBasedDiscovery" policy.
a61af66fc99e Initial load duke parents: diff changeset	1130 bool ReferenceProcessor::discover_reference(oop obj, ReferenceType rt) {
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1131 // Make sure we are discovering refs (rather than processing discovered refs).
0 a61af66fc99e Initial load duke parents: diff changeset	1132 if (!_discovering_refs \|\| !RegisterReferences) {
a61af66fc99e Initial load duke parents: diff changeset	1133 return false;
a61af66fc99e Initial load duke parents: diff changeset	1134 }
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1135 // We only discover active references.
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1136 oop next = java_lang_ref_Reference::next(obj);
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1137 if (next != NULL) { // Ref is no longer active
0 a61af66fc99e Initial load duke parents: diff changeset	1138 return false;
a61af66fc99e Initial load duke parents: diff changeset	1139 }
a61af66fc99e Initial load duke parents: diff changeset	1140
a61af66fc99e Initial load duke parents: diff changeset	1141 HeapWord* obj_addr = (HeapWord*)obj;
a61af66fc99e Initial load duke parents: diff changeset	1142 if (RefDiscoveryPolicy == ReferenceBasedDiscovery &&
a61af66fc99e Initial load duke parents: diff changeset	1143 !_span.contains(obj_addr)) {
a61af66fc99e Initial load duke parents: diff changeset	1144 // Reference is not in the originating generation;
a61af66fc99e Initial load duke parents: diff changeset	1145 // don't treat it specially (i.e. we want to scan it as a normal
a61af66fc99e Initial load duke parents: diff changeset	1146 // object with strong references).
a61af66fc99e Initial load duke parents: diff changeset	1147 return false;
a61af66fc99e Initial load duke parents: diff changeset	1148 }
a61af66fc99e Initial load duke parents: diff changeset	1149
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1150 // We only discover references whose referents are not (yet)
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1151 // known to be strongly reachable.
0 a61af66fc99e Initial load duke parents: diff changeset	1152 if (is_alive_non_header() != NULL) {
1995 8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1153 verify_referent(obj);
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1154 if (is_alive_non_header()->do_object_b(java_lang_ref_Reference::referent(obj))) {
0 a61af66fc99e Initial load duke parents: diff changeset	1155 return false; // referent is reachable
a61af66fc99e Initial load duke parents: diff changeset	1156 }
a61af66fc99e Initial load duke parents: diff changeset	1157 }
453 c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1158 if (rt == REF_SOFT) {
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1159 // For soft refs we can decide now if these are not
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1160 // current candidates for clearing, in which case we
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1161 // can mark through them now, rather than delaying that
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1162 // to the reference-processing phase. Since all current
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1163 // time-stamp policies advance the soft-ref clock only
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1164 // at a major collection cycle, this is always currently
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1165 // accurate.
3992 d1bdeef3e3e2 7098282: G1: assert(interval >= 0) failed: Sanity check, referencePolicy.cpp: 76 johnc parents: 3979 diff changeset	1166 if (!_current_soft_ref_policy->should_clear_reference(obj, _soft_ref_timestamp_clock)) {
453 c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1167 return false;
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1168 }
c96030fff130 6684579: SoftReference processing can be made more efficient ysr parents: 452 diff changeset	1169 }
0 a61af66fc99e Initial load duke parents: diff changeset	1170
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	1171 ResourceMark rm; // Needed for tracing.
4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	1172
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	1173 HeapWord* const discovered_addr = java_lang_ref_Reference::discovered_addr(obj);
37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	1174 const oop discovered = java_lang_ref_Reference::discovered(obj);
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1175 assert(discovered->is_oop_or_null(), "bad discovered field");
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1176 if (discovered != NULL) {
0 a61af66fc99e Initial load duke parents: diff changeset	1177 // The reference has already been discovered...
a61af66fc99e Initial load duke parents: diff changeset	1178 if (TraceReferenceGC) {
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1179 gclog_or_tty->print_cr("Already discovered reference (" INTPTR_FORMAT ": %s)",
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	1180 (void *)obj, obj->klass()->internal_name());
0 a61af66fc99e Initial load duke parents: diff changeset	1181 }
a61af66fc99e Initial load duke parents: diff changeset	1182 if (RefDiscoveryPolicy == ReferentBasedDiscovery) {
a61af66fc99e Initial load duke parents: diff changeset	1183 // assumes that an object is not processed twice;
a61af66fc99e Initial load duke parents: diff changeset	1184 // if it's been already discovered it must be on another
a61af66fc99e Initial load duke parents: diff changeset	1185 // generation's discovered list; so we won't discover it.
a61af66fc99e Initial load duke parents: diff changeset	1186 return false;
a61af66fc99e Initial load duke parents: diff changeset	1187 } else {
a61af66fc99e Initial load duke parents: diff changeset	1188 assert(RefDiscoveryPolicy == ReferenceBasedDiscovery,
a61af66fc99e Initial load duke parents: diff changeset	1189 "Unrecognized policy");
a61af66fc99e Initial load duke parents: diff changeset	1190 // Check assumption that an object is not potentially
a61af66fc99e Initial load duke parents: diff changeset	1191 // discovered twice except by concurrent collectors that potentially
a61af66fc99e Initial load duke parents: diff changeset	1192 // trace the same Reference object twice.
1974 fd1d227ef1b9 6983204: G1: Nightly test nsk/regression/b4958615 failing with +ExplicitGCInvokesConcurrent johnc parents: 1972 diff changeset	1193 assert(UseConcMarkSweepGC \|\| UseG1GC,
fd1d227ef1b9 6983204: G1: Nightly test nsk/regression/b4958615 failing with +ExplicitGCInvokesConcurrent johnc parents: 1972 diff changeset	1194 "Only possible with a concurrent marking collector");
0 a61af66fc99e Initial load duke parents: diff changeset	1195 return true;
a61af66fc99e Initial load duke parents: diff changeset	1196 }
a61af66fc99e Initial load duke parents: diff changeset	1197 }
a61af66fc99e Initial load duke parents: diff changeset	1198
a61af66fc99e Initial load duke parents: diff changeset	1199 if (RefDiscoveryPolicy == ReferentBasedDiscovery) {
1995 8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1200 verify_referent(obj);
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1201 // Discover if and only if EITHER:
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1202 // .. reference is in our span, OR
eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1203 // .. we are an atomic collector and referent is in our span
0 a61af66fc99e Initial load duke parents: diff changeset	1204 if (_span.contains(obj_addr) \|\|
1995 8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1205 (discovery_is_atomic() &&
8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1206 _span.contains(java_lang_ref_Reference::referent(obj)))) {
0 a61af66fc99e Initial load duke parents: diff changeset	1207 // should_enqueue = true;
a61af66fc99e Initial load duke parents: diff changeset	1208 } else {
a61af66fc99e Initial load duke parents: diff changeset	1209 return false;
a61af66fc99e Initial load duke parents: diff changeset	1210 }
a61af66fc99e Initial load duke parents: diff changeset	1211 } else {
a61af66fc99e Initial load duke parents: diff changeset	1212 assert(RefDiscoveryPolicy == ReferenceBasedDiscovery &&
a61af66fc99e Initial load duke parents: diff changeset	1213 _span.contains(obj_addr), "code inconsistency");
a61af66fc99e Initial load duke parents: diff changeset	1214 }
a61af66fc99e Initial load duke parents: diff changeset	1215
a61af66fc99e Initial load duke parents: diff changeset	1216 // Get the right type of discovered queue head.
a61af66fc99e Initial load duke parents: diff changeset	1217 DiscoveredList* list = get_discovered_list(rt);
a61af66fc99e Initial load duke parents: diff changeset	1218 if (list == NULL) {
a61af66fc99e Initial load duke parents: diff changeset	1219 return false; // nothing special needs to be done
a61af66fc99e Initial load duke parents: diff changeset	1220 }
a61af66fc99e Initial load duke parents: diff changeset	1221
a61af66fc99e Initial load duke parents: diff changeset	1222 if (_discovery_is_mt) {
a61af66fc99e Initial load duke parents: diff changeset	1223 add_to_discovered_list_mt(*list, obj, discovered_addr);
a61af66fc99e Initial load duke parents: diff changeset	1224 } else {
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	1225 // We do a raw store here: the field will be visited later when processing
8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	1226 // the discovered references.
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	1227 oop current_head = list->head();
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	1228 // The last ref must have its discovered field pointing to itself.
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	1229 oop next_discovered = (current_head != NULL) ? current_head : obj;
c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	1230
342 37f87013dfd8 6711316: Open source the Garbage-First garbage collector ysr parents: 113 diff changeset	1231 assert(discovered == NULL, "control point invariant");
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	1232 oop_store_raw(discovered_addr, next_discovered);
0 a61af66fc99e Initial load duke parents: diff changeset	1233 list->set_head(obj);
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1234 list->inc_length(1);
0 a61af66fc99e Initial load duke parents: diff changeset	1235
1974 fd1d227ef1b9 6983204: G1: Nightly test nsk/regression/b4958615 failing with +ExplicitGCInvokesConcurrent johnc parents: 1972 diff changeset	1236 if (TraceReferenceGC) {
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1237 gclog_or_tty->print_cr("Discovered reference (" INTPTR_FORMAT ": %s)",
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	1238 (void *)obj, obj->klass()->internal_name());
0 a61af66fc99e Initial load duke parents: diff changeset	1239 }
a61af66fc99e Initial load duke parents: diff changeset	1240 }
3917 eca1193ca245 4965777: GC changes to support use of discovered field for pending references ysr parents: 3915 diff changeset	1241 assert(obj->is_oop(), "Discovered a bad reference");
1995 8df09fb45352 7005259: CMS: BubbleUpRef asserts referent(obj)->is_oop() failed: Enqueued a bad referent ysr parents: 1974 diff changeset	1242 verify_referent(obj);
0 a61af66fc99e Initial load duke parents: diff changeset	1243 return true;
a61af66fc99e Initial load duke parents: diff changeset	1244 }
a61af66fc99e Initial load duke parents: diff changeset	1245
a61af66fc99e Initial load duke parents: diff changeset	1246 // Preclean the discovered references by removing those
a61af66fc99e Initial load duke parents: diff changeset	1247 // whose referents are alive, and by marking from those that
a61af66fc99e Initial load duke parents: diff changeset	1248 // are not active. These lists can be handled here
a61af66fc99e Initial load duke parents: diff changeset	1249 // in any order and, indeed, concurrently.
a61af66fc99e Initial load duke parents: diff changeset	1250 void ReferenceProcessor::preclean_discovered_references(
a61af66fc99e Initial load duke parents: diff changeset	1251 BoolObjectClosure* is_alive,
a61af66fc99e Initial load duke parents: diff changeset	1252 OopClosure* keep_alive,
a61af66fc99e Initial load duke parents: diff changeset	1253 VoidClosure* complete_gc,
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	1254 YieldClosure* yield,
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	1255 GCTimer* gc_timer,
0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	1256 GCId gc_id) {
0 a61af66fc99e Initial load duke parents: diff changeset	1257
a61af66fc99e Initial load duke parents: diff changeset	1258 NOT_PRODUCT(verify_ok_to_handle_reflists());
a61af66fc99e Initial load duke parents: diff changeset	1259
a61af66fc99e Initial load duke parents: diff changeset	1260 // Soft references
a61af66fc99e Initial load duke parents: diff changeset	1261 {
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	1262 GCTraceTime tt("Preclean SoftReferences", PrintGCDetails && PrintReferenceGC,
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	1263 false, gc_timer, gc_id);
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	1264 for (uint i = 0; i < _max_num_q; i++) {
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1265 if (yield->should_return()) {
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1266 return;
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1267 }
0 a61af66fc99e Initial load duke parents: diff changeset	1268 preclean_discovered_reflist(_discoveredSoftRefs[i], is_alive,
a61af66fc99e Initial load duke parents: diff changeset	1269 keep_alive, complete_gc, yield);
a61af66fc99e Initial load duke parents: diff changeset	1270 }
a61af66fc99e Initial load duke parents: diff changeset	1271 }
a61af66fc99e Initial load duke parents: diff changeset	1272
a61af66fc99e Initial load duke parents: diff changeset	1273 // Weak references
a61af66fc99e Initial load duke parents: diff changeset	1274 {
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	1275 GCTraceTime tt("Preclean WeakReferences", PrintGCDetails && PrintReferenceGC,
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	1276 false, gc_timer, gc_id);
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	1277 for (uint i = 0; i < _max_num_q; i++) {
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1278 if (yield->should_return()) {
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1279 return;
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1280 }
0 a61af66fc99e Initial load duke parents: diff changeset	1281 preclean_discovered_reflist(_discoveredWeakRefs[i], is_alive,
a61af66fc99e Initial load duke parents: diff changeset	1282 keep_alive, complete_gc, yield);
a61af66fc99e Initial load duke parents: diff changeset	1283 }
a61af66fc99e Initial load duke parents: diff changeset	1284 }
a61af66fc99e Initial load duke parents: diff changeset	1285
a61af66fc99e Initial load duke parents: diff changeset	1286 // Final references
a61af66fc99e Initial load duke parents: diff changeset	1287 {
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	1288 GCTraceTime tt("Preclean FinalReferences", PrintGCDetails && PrintReferenceGC,
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	1289 false, gc_timer, gc_id);
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	1290 for (uint i = 0; i < _max_num_q; i++) {
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1291 if (yield->should_return()) {
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1292 return;
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1293 }
0 a61af66fc99e Initial load duke parents: diff changeset	1294 preclean_discovered_reflist(_discoveredFinalRefs[i], is_alive,
a61af66fc99e Initial load duke parents: diff changeset	1295 keep_alive, complete_gc, yield);
a61af66fc99e Initial load duke parents: diff changeset	1296 }
a61af66fc99e Initial load duke parents: diff changeset	1297 }
a61af66fc99e Initial load duke parents: diff changeset	1298
a61af66fc99e Initial load duke parents: diff changeset	1299 // Phantom references
a61af66fc99e Initial load duke parents: diff changeset	1300 {
10405 f2110083203d 8005849: JEP 167: Event-Based JVM Tracing sla parents: 10327 diff changeset	1301 GCTraceTime tt("Preclean PhantomReferences", PrintGCDetails && PrintReferenceGC,
20190 0982ec23da03 8043607: Add a GC id as a log decoration similar to PrintGCTimeStamps brutisso parents: 17976 diff changeset	1302 false, gc_timer, gc_id);
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	1303 for (uint i = 0; i < _max_num_q; i++) {
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1304 if (yield->should_return()) {
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1305 return;
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1306 }
0 a61af66fc99e Initial load duke parents: diff changeset	1307 preclean_discovered_reflist(_discoveredPhantomRefs[i], is_alive,
a61af66fc99e Initial load duke parents: diff changeset	1308 keep_alive, complete_gc, yield);
a61af66fc99e Initial load duke parents: diff changeset	1309 }
a61af66fc99e Initial load duke parents: diff changeset	1310 }
a61af66fc99e Initial load duke parents: diff changeset	1311 }
a61af66fc99e Initial load duke parents: diff changeset	1312
a61af66fc99e Initial load duke parents: diff changeset	1313 // Walk the given discovered ref list, and remove all reference objects
a61af66fc99e Initial load duke parents: diff changeset	1314 // whose referents are still alive, whose referents are NULL or which
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1315 // are not active (have a non-NULL next field). NOTE: When we are
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1316 // thus precleaning the ref lists (which happens single-threaded today),
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1317 // we do not disable refs discovery to honour the correct semantics of
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1318 // java.lang.Reference. As a result, we need to be careful below
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1319 // that ref removal steps interleave safely with ref discovery steps
00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1320 // (in this thread).
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1321 void
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1322 ReferenceProcessor::preclean_discovered_reflist(DiscoveredList& refs_list,
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1323 BoolObjectClosure* is_alive,
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1324 OopClosure* keep_alive,
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1325 VoidClosure* complete_gc,
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1326 YieldClosure* yield) {
17976 8e20ef014b08 8043239: G1: Missing post barrier in processing of j.l.ref.Reference objects brutisso parents: 17937 diff changeset	1327 DiscoveredListIterator iter(refs_list, keep_alive, is_alive);
0 a61af66fc99e Initial load duke parents: diff changeset	1328 while (iter.has_next()) {
a61af66fc99e Initial load duke parents: diff changeset	1329 iter.load_ptrs(DEBUG_ONLY(true /* allow_null_referent */));
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1330 oop obj = iter.obj();
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1331 oop next = java_lang_ref_Reference::next(obj);
0 a61af66fc99e Initial load duke parents: diff changeset	1332 if (iter.referent() == NULL \|\| iter.is_referent_alive() \|\|
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1333 next != NULL) {
0 a61af66fc99e Initial load duke parents: diff changeset	1334 // The referent has been cleared, or is alive, or the Reference is not
a61af66fc99e Initial load duke parents: diff changeset	1335 // active; we need to trace and mark its cohort.
a61af66fc99e Initial load duke parents: diff changeset	1336 if (TraceReferenceGC) {
a61af66fc99e Initial load duke parents: diff changeset	1337 gclog_or_tty->print_cr("Precleaning Reference (" INTPTR_FORMAT ": %s)",
12316 190899198332 7195622: CheckUnhandledOops has limited usefulness now hseigel parents: 10405 diff changeset	1338 (void *)iter.obj(), iter.obj()->klass()->internal_name());
0 a61af66fc99e Initial load duke parents: diff changeset	1339 }
a61af66fc99e Initial load duke parents: diff changeset	1340 // Remove Reference object from list
a61af66fc99e Initial load duke parents: diff changeset	1341 iter.remove();
a61af66fc99e Initial load duke parents: diff changeset	1342 // Keep alive its cohort.
a61af66fc99e Initial load duke parents: diff changeset	1343 iter.make_referent_alive();
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1344 if (UseCompressedOops) {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1345 narrowOop* next_addr = (narrowOop*)java_lang_ref_Reference::next_addr(obj);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1346 keep_alive->do_oop(next_addr);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1347 } else {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1348 oop* next_addr = (oop*)java_lang_ref_Reference::next_addr(obj);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1349 keep_alive->do_oop(next_addr);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 5 diff changeset	1350 }
452 00b023ae2d78 6722113: CMS: Incorrect overflow handling during precleaning of Reference lists ysr parents: 356 diff changeset	1351 iter.move_to_next();
0 a61af66fc99e Initial load duke parents: diff changeset	1352 } else {
a61af66fc99e Initial load duke parents: diff changeset	1353 iter.next();
a61af66fc99e Initial load duke parents: diff changeset	1354 }
a61af66fc99e Initial load duke parents: diff changeset	1355 }
a61af66fc99e Initial load duke parents: diff changeset	1356 // Close the reachable set
a61af66fc99e Initial load duke parents: diff changeset	1357 complete_gc->do_void();
a61af66fc99e Initial load duke parents: diff changeset	1358
a61af66fc99e Initial load duke parents: diff changeset	1359 NOT_PRODUCT(
2369 92da084fefc9 6668573: CMS: reference processing crash if ParallelCMSThreads > ParallelGCThreads ysr parents: 1995 diff changeset	1360 if (PrintGCDetails && PrintReferenceGC && (iter.processed() > 0)) {
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	1361 gclog_or_tty->print_cr(" Dropped %d Refs out of %d "
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	1362 "Refs in discovered list " INTPTR_FORMAT,
8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	1363 iter.removed(), iter.processed(), (address)refs_list.head());
0 a61af66fc99e Initial load duke parents: diff changeset	1364 }
a61af66fc99e Initial load duke parents: diff changeset	1365 )
a61af66fc99e Initial load duke parents: diff changeset	1366 }
a61af66fc99e Initial load duke parents: diff changeset	1367
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	1368 const char* ReferenceProcessor::list_name(uint i) {
3979 4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	1369 assert(i >= 0 && i <= _max_num_q * number_of_subclasses_of_ref(),
4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	1370 "Out of bounds index");
4dfb2df418f2 6484982: G1: process references during evacuation pauses johnc parents: 3917 diff changeset	1371
1833 8b10f48633dc 6984287: Regularize how GC parallel workers are specified. jmasa parents: 1552 diff changeset	1372 int j = i / _max_num_q;
0 a61af66fc99e Initial load duke parents: diff changeset	1373 switch (j) {
a61af66fc99e Initial load duke parents: diff changeset	1374 case 0: return "SoftRef";
a61af66fc99e Initial load duke parents: diff changeset	1375 case 1: return "WeakRef";
a61af66fc99e Initial load duke parents: diff changeset	1376 case 2: return "FinalRef";
a61af66fc99e Initial load duke parents: diff changeset	1377 case 3: return "PhantomRef";
a61af66fc99e Initial load duke parents: diff changeset	1378 }
a61af66fc99e Initial load duke parents: diff changeset	1379 ShouldNotReachHere();
a61af66fc99e Initial load duke parents: diff changeset	1380 return NULL;
a61af66fc99e Initial load duke parents: diff changeset	1381 }
a61af66fc99e Initial load duke parents: diff changeset	1382
a61af66fc99e Initial load duke parents: diff changeset	1383 #ifndef PRODUCT
a61af66fc99e Initial load duke parents: diff changeset	1384 void ReferenceProcessor::verify_ok_to_handle_reflists() {
a61af66fc99e Initial load duke parents: diff changeset	1385 // empty for now
a61af66fc99e Initial load duke parents: diff changeset	1386 }
a61af66fc99e Initial load duke parents: diff changeset	1387 #endif
a61af66fc99e Initial load duke parents: diff changeset	1388
a61af66fc99e Initial load duke parents: diff changeset	1389 #ifndef PRODUCT
a61af66fc99e Initial load duke parents: diff changeset	1390 void ReferenceProcessor::clear_discovered_references() {
a61af66fc99e Initial load duke parents: diff changeset	1391 guarantee(!_discovering_refs, "Discovering refs?");
4728 441e946dc1af 7121618: Change type of number of GC workers to unsigned int. jmasa parents: 4712 diff changeset	1392 for (uint i = 0; i < _max_num_q * number_of_subclasses_of_ref(); i++) {
4014 bf2d2b8b1726 7095243: Disambiguate ReferenceProcessor::_discoveredSoftRefs johnc parents: 3992 diff changeset	1393 clear_discovered_references(_discovered_refs[i]);
0 a61af66fc99e Initial load duke parents: diff changeset	1394 }
a61af66fc99e Initial load duke parents: diff changeset	1395 }
3915 c2bf0120ee5d 7085906: Replace the permgen allocated sentinelRef with a self-looped end stefank parents: 2369 diff changeset	1396
0 a61af66fc99e Initial load duke parents: diff changeset	1397 #endif // PRODUCT

Mercurial > hg > graal-compiler

annotate src/share/vm/memory/referenceProcessor.cpp @ 20190:0982ec23da03