src/share/vm/gc_implementation/g1/concurrentMarkThread.cpp

Fri, 09 Sep 2011 05:20:58 -0400

author
tonyp
date
Fri, 09 Sep 2011 05:20:58 -0400
changeset 3121
3bddbf0f57d6
parent 3065
ff53346271fe
child 3208
ec4b032a4977
permissions
-rw-r--r--

7087717: G1: make the G1PrintRegionLivenessInfo parameter diagnostic
Reviewed-by: brutisso, ysr

ysr@777 1 /*
tonyp@2472 2 * Copyright (c) 2001, 2011, Oracle and/or its affiliates. All rights reserved.
ysr@777 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@777 4 *
ysr@777 5 * This code is free software; you can redistribute it and/or modify it
ysr@777 6 * under the terms of the GNU General Public License version 2 only, as
ysr@777 7 * published by the Free Software Foundation.
ysr@777 8 *
ysr@777 9 * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@777 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@777 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
ysr@777 12 * version 2 for more details (a copy is included in the LICENSE file that
ysr@777 13 * accompanied this code).
ysr@777 14 *
ysr@777 15 * You should have received a copy of the GNU General Public License version
ysr@777 16 * 2 along with this work; if not, write to the Free Software Foundation,
ysr@777 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@777 18 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
ysr@777 22 *
ysr@777 23 */
ysr@777 24
stefank@2314 25 #include "precompiled.hpp"
stefank@2314 26 #include "gc_implementation/g1/concurrentMarkThread.inline.hpp"
stefank@2314 27 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
stefank@2314 28 #include "gc_implementation/g1/g1CollectorPolicy.hpp"
stefank@2314 29 #include "gc_implementation/g1/g1MMUTracker.hpp"
stefank@2314 30 #include "gc_implementation/g1/vm_operations_g1.hpp"
stefank@2314 31 #include "memory/resourceArea.hpp"
stefank@2314 32 #include "runtime/vmThread.hpp"
ysr@777 33
ysr@777 34 // ======= Concurrent Mark Thread ========
ysr@777 35
ysr@777 36 // The CM thread is created when the G1 garbage collector is used
ysr@777 37
ysr@777 38 SurrogateLockerThread*
ysr@777 39 ConcurrentMarkThread::_slt = NULL;
ysr@777 40
ysr@777 41 ConcurrentMarkThread::ConcurrentMarkThread(ConcurrentMark* cm) :
ysr@777 42 ConcurrentGCThread(),
ysr@777 43 _cm(cm),
ysr@777 44 _started(false),
ysr@777 45 _in_progress(false),
ysr@777 46 _vtime_accum(0.0),
ysr@777 47 _vtime_mark_accum(0.0),
ysr@777 48 _vtime_count_accum(0.0)
ysr@777 49 {
ysr@777 50 create_and_start();
ysr@777 51 }
ysr@777 52
ysr@777 53 class CMCheckpointRootsFinalClosure: public VoidClosure {
ysr@777 54
ysr@777 55 ConcurrentMark* _cm;
ysr@777 56 public:
ysr@777 57
ysr@777 58 CMCheckpointRootsFinalClosure(ConcurrentMark* cm) :
ysr@777 59 _cm(cm) {}
ysr@777 60
ysr@777 61 void do_void(){
ysr@777 62 _cm->checkpointRootsFinal(false); // !clear_all_soft_refs
ysr@777 63 }
ysr@777 64 };
ysr@777 65
ysr@777 66 class CMCleanUp: public VoidClosure {
ysr@777 67 ConcurrentMark* _cm;
ysr@777 68 public:
ysr@777 69
ysr@777 70 CMCleanUp(ConcurrentMark* cm) :
ysr@777 71 _cm(cm) {}
ysr@777 72
ysr@777 73 void do_void(){
ysr@777 74 _cm->cleanup();
ysr@777 75 }
ysr@777 76 };
ysr@777 77
ysr@777 78
ysr@777 79
ysr@777 80 void ConcurrentMarkThread::run() {
ysr@777 81 initialize_in_thread();
ysr@777 82 _vtime_start = os::elapsedVTime();
ysr@777 83 wait_for_universe_init();
ysr@777 84
tonyp@2472 85 G1CollectedHeap* g1h = G1CollectedHeap::heap();
tonyp@2472 86 G1CollectorPolicy* g1_policy = g1h->g1_policy();
ysr@777 87 G1MMUTracker *mmu_tracker = g1_policy->mmu_tracker();
ysr@777 88 Thread *current_thread = Thread::current();
ysr@777 89
ysr@777 90 while (!_should_terminate) {
ysr@777 91 // wait until started is set.
ysr@777 92 sleepBeforeNextCycle();
ysr@777 93 {
ysr@777 94 ResourceMark rm;
ysr@777 95 HandleMark hm;
ysr@777 96 double cycle_start = os::elapsedVTime();
ysr@777 97 double mark_start_sec = os::elapsedTime();
ysr@777 98 char verbose_str[128];
ysr@777 99
ysr@777 100 if (PrintGC) {
ysr@777 101 gclog_or_tty->date_stamp(PrintGCDateStamps);
ysr@777 102 gclog_or_tty->stamp(PrintGCTimeStamps);
tonyp@1054 103 gclog_or_tty->print_cr("[GC concurrent-mark-start]");
ysr@777 104 }
ysr@777 105
ysr@777 106 int iter = 0;
ysr@777 107 do {
ysr@777 108 iter++;
ysr@777 109 if (!cm()->has_aborted()) {
ysr@777 110 _cm->markFromRoots();
ysr@777 111 }
ysr@777 112
ysr@777 113 double mark_end_time = os::elapsedVTime();
ysr@777 114 double mark_end_sec = os::elapsedTime();
ysr@777 115 _vtime_mark_accum += (mark_end_time - cycle_start);
ysr@777 116 if (!cm()->has_aborted()) {
ysr@777 117 if (g1_policy->adaptive_young_list_length()) {
ysr@777 118 double now = os::elapsedTime();
ysr@777 119 double remark_prediction_ms = g1_policy->predict_remark_time_ms();
ysr@777 120 jlong sleep_time_ms = mmu_tracker->when_ms(now, remark_prediction_ms);
ysr@777 121 os::sleep(current_thread, sleep_time_ms, false);
ysr@777 122 }
ysr@777 123
ysr@777 124 if (PrintGC) {
ysr@777 125 gclog_or_tty->date_stamp(PrintGCDateStamps);
ysr@777 126 gclog_or_tty->stamp(PrintGCTimeStamps);
ysr@777 127 gclog_or_tty->print_cr("[GC concurrent-mark-end, %1.7lf sec]",
ysr@777 128 mark_end_sec - mark_start_sec);
ysr@777 129 }
ysr@777 130
ysr@777 131 CMCheckpointRootsFinalClosure final_cl(_cm);
ysr@777 132 sprintf(verbose_str, "GC remark");
ysr@777 133 VM_CGC_Operation op(&final_cl, verbose_str);
ysr@777 134 VMThread::execute(&op);
ysr@777 135 }
ysr@777 136 if (cm()->restart_for_overflow() &&
ysr@777 137 G1TraceMarkStackOverflow) {
ysr@777 138 gclog_or_tty->print_cr("Restarting conc marking because of MS overflow "
ysr@777 139 "in remark (restart #%d).", iter);
ysr@777 140 }
ysr@777 141
ysr@777 142 if (cm()->restart_for_overflow()) {
ysr@777 143 if (PrintGC) {
ysr@777 144 gclog_or_tty->date_stamp(PrintGCDateStamps);
ysr@777 145 gclog_or_tty->stamp(PrintGCTimeStamps);
ysr@777 146 gclog_or_tty->print_cr("[GC concurrent-mark-restart-for-overflow]");
ysr@777 147 }
ysr@777 148 }
ysr@777 149 } while (cm()->restart_for_overflow());
ysr@777 150 double counting_start_time = os::elapsedVTime();
ysr@777 151
ysr@777 152 // YSR: These look dubious (i.e. redundant) !!! FIX ME
ysr@777 153 slt()->manipulatePLL(SurrogateLockerThread::acquirePLL);
ysr@777 154 slt()->manipulatePLL(SurrogateLockerThread::releaseAndNotifyPLL);
ysr@777 155
ysr@777 156 if (!cm()->has_aborted()) {
ysr@777 157 double count_start_sec = os::elapsedTime();
ysr@777 158 if (PrintGC) {
ysr@777 159 gclog_or_tty->date_stamp(PrintGCDateStamps);
ysr@777 160 gclog_or_tty->stamp(PrintGCTimeStamps);
ysr@777 161 gclog_or_tty->print_cr("[GC concurrent-count-start]");
ysr@777 162 }
ysr@777 163
ysr@777 164 _sts.join();
ysr@777 165 _cm->calcDesiredRegions();
ysr@777 166 _sts.leave();
ysr@777 167
ysr@777 168 if (!cm()->has_aborted()) {
ysr@777 169 double count_end_sec = os::elapsedTime();
ysr@777 170 if (PrintGC) {
ysr@777 171 gclog_or_tty->date_stamp(PrintGCDateStamps);
ysr@777 172 gclog_or_tty->stamp(PrintGCTimeStamps);
ysr@777 173 gclog_or_tty->print_cr("[GC concurrent-count-end, %1.7lf]",
ysr@777 174 count_end_sec - count_start_sec);
ysr@777 175 }
ysr@777 176 }
ysr@777 177 }
ysr@777 178 double end_time = os::elapsedVTime();
ysr@777 179 _vtime_count_accum += (end_time - counting_start_time);
ysr@777 180 // Update the total virtual time before doing this, since it will try
ysr@777 181 // to measure it to get the vtime for this marking. We purposely
ysr@777 182 // neglect the presumably-short "completeCleanup" phase here.
ysr@777 183 _vtime_accum = (end_time - _vtime_start);
ysr@777 184 if (!cm()->has_aborted()) {
ysr@777 185 if (g1_policy->adaptive_young_list_length()) {
ysr@777 186 double now = os::elapsedTime();
ysr@777 187 double cleanup_prediction_ms = g1_policy->predict_cleanup_time_ms();
ysr@777 188 jlong sleep_time_ms = mmu_tracker->when_ms(now, cleanup_prediction_ms);
ysr@777 189 os::sleep(current_thread, sleep_time_ms, false);
ysr@777 190 }
ysr@777 191
ysr@777 192 CMCleanUp cl_cl(_cm);
ysr@777 193 sprintf(verbose_str, "GC cleanup");
ysr@777 194 VM_CGC_Operation op(&cl_cl, verbose_str);
ysr@777 195 VMThread::execute(&op);
ysr@777 196 } else {
tonyp@2472 197 g1h->set_marking_complete();
ysr@777 198 }
ysr@777 199
tonyp@2472 200 // Check if cleanup set the free_regions_coming flag. If it
tonyp@2472 201 // hasn't, we can just skip the next step.
tonyp@2472 202 if (g1h->free_regions_coming()) {
tonyp@2472 203 // The following will finish freeing up any regions that we
tonyp@2472 204 // found to be empty during cleanup. We'll do this part
tonyp@2472 205 // without joining the suspendible set. If an evacuation pause
tonyp@2643 206 // takes place, then we would carry on freeing regions in
tonyp@2472 207 // case they are needed by the pause. If a Full GC takes
tonyp@2643 208 // place, it would wait for us to process the regions
tonyp@2472 209 // reclaimed by cleanup.
tonyp@2472 210
ysr@777 211 double cleanup_start_sec = os::elapsedTime();
ysr@777 212 if (PrintGC) {
ysr@777 213 gclog_or_tty->date_stamp(PrintGCDateStamps);
ysr@777 214 gclog_or_tty->stamp(PrintGCTimeStamps);
ysr@777 215 gclog_or_tty->print_cr("[GC concurrent-cleanup-start]");
ysr@777 216 }
ysr@777 217
ysr@777 218 // Now do the remainder of the cleanup operation.
ysr@777 219 _cm->completeCleanup();
tonyp@2501 220 // Notify anyone who's waiting that there are no more free
tonyp@2501 221 // regions coming. We have to do this before we join the STS,
tonyp@2501 222 // otherwise we might deadlock: a GC worker could be blocked
tonyp@2501 223 // waiting for the notification whereas this thread will be
tonyp@2501 224 // blocked for the pause to finish while it's trying to join
tonyp@2501 225 // the STS, which is conditional on the GC workers finishing.
tonyp@2501 226 g1h->reset_free_regions_coming();
tonyp@2501 227
tonyp@2492 228 _sts.join();
tonyp@2472 229 g1_policy->record_concurrent_mark_cleanup_completed();
tonyp@2492 230 _sts.leave();
ysr@777 231
tonyp@2472 232 double cleanup_end_sec = os::elapsedTime();
tonyp@2472 233 if (PrintGC) {
tonyp@2472 234 gclog_or_tty->date_stamp(PrintGCDateStamps);
tonyp@2472 235 gclog_or_tty->stamp(PrintGCTimeStamps);
tonyp@2472 236 gclog_or_tty->print_cr("[GC concurrent-cleanup-end, %1.7lf]",
tonyp@2472 237 cleanup_end_sec - cleanup_start_sec);
ysr@777 238 }
ysr@777 239 }
tonyp@2472 240 guarantee(cm()->cleanup_list_is_empty(),
tonyp@2472 241 "at this point there should be no regions on the cleanup list");
ysr@777 242
ysr@777 243 if (cm()->has_aborted()) {
ysr@777 244 if (PrintGC) {
ysr@777 245 gclog_or_tty->date_stamp(PrintGCDateStamps);
ysr@777 246 gclog_or_tty->stamp(PrintGCTimeStamps);
ysr@777 247 gclog_or_tty->print_cr("[GC concurrent-mark-abort]");
ysr@777 248 }
ysr@777 249 }
ysr@777 250
ysr@777 251 // we now want to allow clearing of the marking bitmap to be
ysr@777 252 // suspended by a collection pause.
ysr@777 253 _sts.join();
ysr@777 254 _cm->clearNextBitmap();
ysr@777 255 _sts.leave();
ysr@777 256 }
tonyp@2011 257
tonyp@2011 258 // Update the number of full collections that have been
tonyp@2011 259 // completed. This will also notify the FullGCCount_lock in case a
tonyp@2011 260 // Java thread is waiting for a full GC to happen (e.g., it
tonyp@2011 261 // called System.gc() with +ExplicitGCInvokesConcurrent).
tonyp@2372 262 _sts.join();
tonyp@2472 263 g1h->increment_full_collections_completed(true /* concurrent */);
tonyp@2372 264 _sts.leave();
ysr@777 265 }
ysr@777 266 assert(_should_terminate, "just checking");
ysr@777 267
ysr@777 268 terminate();
ysr@777 269 }
ysr@777 270
ysr@777 271
ysr@777 272 void ConcurrentMarkThread::yield() {
ysr@777 273 _sts.yield("Concurrent Mark");
ysr@777 274 }
ysr@777 275
ysr@777 276 void ConcurrentMarkThread::stop() {
ysr@777 277 // it is ok to take late safepoints here, if needed
ysr@777 278 MutexLockerEx mu(Terminator_lock);
ysr@777 279 _should_terminate = true;
ysr@777 280 while (!_has_terminated) {
ysr@777 281 Terminator_lock->wait();
ysr@777 282 }
ysr@777 283 }
ysr@777 284
tonyp@1454 285 void ConcurrentMarkThread::print() const {
tonyp@1454 286 print_on(tty);
tonyp@1454 287 }
tonyp@1454 288
tonyp@1454 289 void ConcurrentMarkThread::print_on(outputStream* st) const {
tonyp@1454 290 st->print("\"G1 Main Concurrent Mark GC Thread\" ");
tonyp@1454 291 Thread::print_on(st);
tonyp@1454 292 st->cr();
ysr@777 293 }
ysr@777 294
ysr@777 295 void ConcurrentMarkThread::sleepBeforeNextCycle() {
ysr@777 296 // We join here because we don't want to do the "shouldConcurrentMark()"
ysr@777 297 // below while the world is otherwise stopped.
johnc@2195 298 assert(!in_progress(), "should have been cleared");
johnc@2195 299
ysr@777 300 MutexLockerEx x(CGC_lock, Mutex::_no_safepoint_check_flag);
ysr@777 301 while (!started()) {
ysr@777 302 CGC_lock->wait(Mutex::_no_safepoint_check_flag);
ysr@777 303 }
ysr@777 304 set_in_progress();
ysr@777 305 clear_started();
ysr@777 306 }
ysr@777 307
ysr@777 308 // Note: this method, although exported by the ConcurrentMarkSweepThread,
ysr@777 309 // which is a non-JavaThread, can only be called by a JavaThread.
ysr@777 310 // Currently this is done at vm creation time (post-vm-init) by the
ysr@777 311 // main/Primordial (Java)Thread.
ysr@777 312 // XXX Consider changing this in the future to allow the CMS thread
ysr@777 313 // itself to create this thread?
ysr@777 314 void ConcurrentMarkThread::makeSurrogateLockerThread(TRAPS) {
ysr@777 315 assert(_slt == NULL, "SLT already created");
ysr@777 316 _slt = SurrogateLockerThread::make(THREAD);
ysr@777 317 }

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