src/share/vm/gc_implementation/shared/vmGCOperations.cpp

Tue, 18 May 2010 11:02:18 -0700

author
jcoomes
date
Tue, 18 May 2010 11:02:18 -0700
changeset 1902
fb1a39993f69
parent 1827
bdb5361c461c
child 1907
c18cbe5936b8
permissions
-rw-r--r--

6951319: enable solaris builds using Sun Studio 12 update 1
Reviewed-by: kamg, ysr, dholmes, johnc

duke@435 1 /*
xdono@631 2 * Copyright 2005-2008 Sun Microsystems, Inc. All Rights Reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
duke@435 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435 20 * CA 95054 USA or visit www.sun.com if you need additional information or
duke@435 21 * have any questions.
duke@435 22 *
duke@435 23 */
duke@435 24 # include "incls/_precompiled.incl"
duke@435 25 # include "incls/_vmGCOperations.cpp.incl"
duke@435 26
duke@435 27 HS_DTRACE_PROBE_DECL1(hotspot, gc__begin, bool);
duke@435 28 HS_DTRACE_PROBE_DECL(hotspot, gc__end);
duke@435 29
duke@435 30 // The same dtrace probe can't be inserted in two different files, so we
duke@435 31 // have to call it here, so it's only in one file. Can't create new probes
duke@435 32 // for the other file anymore. The dtrace probes have to remain stable.
duke@435 33 void VM_GC_Operation::notify_gc_begin(bool full) {
duke@435 34 HS_DTRACE_PROBE1(hotspot, gc__begin, full);
jcoomes@1902 35 HS_DTRACE_WORKAROUND_TAIL_CALL_BUG();
duke@435 36 }
duke@435 37
duke@435 38 void VM_GC_Operation::notify_gc_end() {
duke@435 39 HS_DTRACE_PROBE(hotspot, gc__end);
jcoomes@1902 40 HS_DTRACE_WORKAROUND_TAIL_CALL_BUG();
duke@435 41 }
duke@435 42
duke@435 43 void VM_GC_Operation::acquire_pending_list_lock() {
duke@435 44 // we may enter this with pending exception set
duke@435 45 instanceRefKlass::acquire_pending_list_lock(&_pending_list_basic_lock);
duke@435 46 }
duke@435 47
duke@435 48
duke@435 49 void VM_GC_Operation::release_and_notify_pending_list_lock() {
duke@435 50
duke@435 51 instanceRefKlass::release_and_notify_pending_list_lock(&_pending_list_basic_lock);
duke@435 52 }
duke@435 53
duke@435 54 // Allocations may fail in several threads at about the same time,
duke@435 55 // resulting in multiple gc requests. We only want to do one of them.
duke@435 56 // In case a GC locker is active and the need for a GC is already signalled,
duke@435 57 // we want to skip this GC attempt altogether, without doing a futile
duke@435 58 // safepoint operation.
duke@435 59 bool VM_GC_Operation::skip_operation() const {
duke@435 60 bool skip = (_gc_count_before != Universe::heap()->total_collections());
duke@435 61 if (_full && skip) {
duke@435 62 skip = (_full_gc_count_before != Universe::heap()->total_full_collections());
duke@435 63 }
duke@435 64 if (!skip && GC_locker::is_active_and_needs_gc()) {
duke@435 65 skip = Universe::heap()->is_maximal_no_gc();
duke@435 66 assert(!(skip && (_gc_cause == GCCause::_gc_locker)),
duke@435 67 "GC_locker cannot be active when initiating GC");
duke@435 68 }
duke@435 69 return skip;
duke@435 70 }
duke@435 71
duke@435 72 bool VM_GC_Operation::doit_prologue() {
duke@435 73 assert(Thread::current()->is_Java_thread(), "just checking");
duke@435 74
duke@435 75 acquire_pending_list_lock();
duke@435 76 // If the GC count has changed someone beat us to the collection
duke@435 77 // Get the Heap_lock after the pending_list_lock.
duke@435 78 Heap_lock->lock();
ysr@777 79
duke@435 80 // Check invocations
duke@435 81 if (skip_operation()) {
duke@435 82 // skip collection
duke@435 83 Heap_lock->unlock();
duke@435 84 release_and_notify_pending_list_lock();
duke@435 85 _prologue_succeeded = false;
duke@435 86 } else {
duke@435 87 _prologue_succeeded = true;
ysr@777 88 SharedHeap* sh = SharedHeap::heap();
ysr@777 89 if (sh != NULL) sh->_thread_holds_heap_lock_for_gc = true;
duke@435 90 }
duke@435 91 return _prologue_succeeded;
duke@435 92 }
duke@435 93
duke@435 94
duke@435 95 void VM_GC_Operation::doit_epilogue() {
duke@435 96 assert(Thread::current()->is_Java_thread(), "just checking");
duke@435 97 // Release the Heap_lock first.
ysr@777 98 SharedHeap* sh = SharedHeap::heap();
ysr@777 99 if (sh != NULL) sh->_thread_holds_heap_lock_for_gc = false;
duke@435 100 Heap_lock->unlock();
duke@435 101 release_and_notify_pending_list_lock();
duke@435 102 }
duke@435 103
duke@435 104 bool VM_GC_HeapInspection::doit_prologue() {
duke@435 105 if (Universe::heap()->supports_heap_inspection()) {
duke@435 106 return VM_GC_Operation::doit_prologue();
duke@435 107 } else {
duke@435 108 return false;
duke@435 109 }
duke@435 110 }
duke@435 111
duke@435 112 bool VM_GC_HeapInspection::skip_operation() const {
duke@435 113 assert(Universe::heap()->supports_heap_inspection(), "huh?");
duke@435 114 return false;
duke@435 115 }
duke@435 116
duke@435 117 void VM_GC_HeapInspection::doit() {
duke@435 118 HandleMark hm;
duke@435 119 CollectedHeap* ch = Universe::heap();
kevinw@1827 120 ch->ensure_parsability(false); // must happen, even if collection does
kevinw@1827 121 // not happen (e.g. due to GC_locker)
duke@435 122 if (_full_gc) {
kevinw@1827 123 // The collection attempt below would be skipped anyway if
kevinw@1827 124 // the gc locker is held. The following dump may then be a tad
kevinw@1827 125 // misleading to someone expecting only live objects to show
kevinw@1827 126 // up in the dump (see CR 6944195). Just issue a suitable warning
kevinw@1827 127 // in that case and do not attempt to do a collection.
kevinw@1827 128 // The latter is a subtle point, because even a failed attempt
kevinw@1827 129 // to GC will, in fact, induce one in the future, which we
kevinw@1827 130 // probably want to avoid in this case because the GC that we may
kevinw@1827 131 // be about to attempt holds value for us only
kevinw@1827 132 // if it happens now and not if it happens in the eventual
kevinw@1827 133 // future.
kevinw@1827 134 if (GC_locker::is_active()) {
kevinw@1827 135 warning("GC locker is held; pre-dump GC was skipped");
kevinw@1827 136 } else {
kevinw@1827 137 ch->collect_as_vm_thread(GCCause::_heap_inspection);
kevinw@1827 138 }
duke@435 139 }
ysr@1050 140 HeapInspection::heap_inspection(_out, _need_prologue /* need_prologue */);
duke@435 141 }
duke@435 142
duke@435 143
duke@435 144 void VM_GenCollectForAllocation::doit() {
duke@435 145 JvmtiGCForAllocationMarker jgcm;
duke@435 146 notify_gc_begin(false);
duke@435 147
duke@435 148 GenCollectedHeap* gch = GenCollectedHeap::heap();
duke@435 149 GCCauseSetter gccs(gch, _gc_cause);
duke@435 150 _res = gch->satisfy_failed_allocation(_size, _tlab);
duke@435 151 assert(gch->is_in_reserved_or_null(_res), "result not in heap");
duke@435 152
duke@435 153 if (_res == NULL && GC_locker::is_active_and_needs_gc()) {
duke@435 154 set_gc_locked();
duke@435 155 }
duke@435 156 notify_gc_end();
duke@435 157 }
duke@435 158
duke@435 159 void VM_GenCollectFull::doit() {
duke@435 160 JvmtiGCFullMarker jgcm;
duke@435 161 notify_gc_begin(true);
duke@435 162
duke@435 163 GenCollectedHeap* gch = GenCollectedHeap::heap();
duke@435 164 GCCauseSetter gccs(gch, _gc_cause);
duke@435 165 gch->do_full_collection(gch->must_clear_all_soft_refs(), _max_level);
duke@435 166 notify_gc_end();
duke@435 167 }
apetrusenko@574 168
apetrusenko@574 169 void VM_GenCollectForPermanentAllocation::doit() {
apetrusenko@574 170 JvmtiGCForAllocationMarker jgcm;
apetrusenko@574 171 notify_gc_begin(true);
ysr@777 172 SharedHeap* heap = (SharedHeap*)Universe::heap();
ysr@777 173 GCCauseSetter gccs(heap, _gc_cause);
ysr@777 174 switch (heap->kind()) {
ysr@777 175 case (CollectedHeap::GenCollectedHeap): {
ysr@777 176 GenCollectedHeap* gch = (GenCollectedHeap*)heap;
ysr@777 177 gch->do_full_collection(gch->must_clear_all_soft_refs(),
ysr@777 178 gch->n_gens() - 1);
ysr@777 179 break;
ysr@777 180 }
ysr@777 181 #ifndef SERIALGC
ysr@777 182 case (CollectedHeap::G1CollectedHeap): {
ysr@777 183 G1CollectedHeap* g1h = (G1CollectedHeap*)heap;
ysr@777 184 g1h->do_full_collection(_gc_cause == GCCause::_last_ditch_collection);
ysr@777 185 break;
ysr@777 186 }
ysr@777 187 #endif // SERIALGC
ysr@777 188 default:
ysr@777 189 ShouldNotReachHere();
ysr@777 190 }
ysr@777 191 _res = heap->perm_gen()->allocate(_size, false);
ysr@777 192 assert(heap->is_in_reserved_or_null(_res), "result not in heap");
apetrusenko@574 193 if (_res == NULL && GC_locker::is_active_and_needs_gc()) {
apetrusenko@574 194 set_gc_locked();
apetrusenko@574 195 }
apetrusenko@574 196 notify_gc_end();
apetrusenko@574 197 }

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