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src/hotspot/share/runtime/serviceThread.cpp

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rev 55489 : Checkpoint latest preliminary review patches for full OpenJDK review; merge with 8222295.patch.
rev 55493 : imported patch dcubed.monitor_deflate_conc.v2.04
rev 55494 : imported patch dcubed.monitor_deflate_conc.v2.05


  91 
  92 void ServiceThread::service_thread_entry(JavaThread* jt, TRAPS) {
  93   OopStorage* const oopstorages[] = {
  94     JNIHandles::global_handles(),
  95     JNIHandles::weak_global_handles(),
  96     StringTable::weak_storage(),
  97     SystemDictionary::vm_weak_oop_storage()
  98   };
  99   const size_t oopstorage_count = ARRAY_SIZE(oopstorages);
 100 
 101   while (true) {
 102     bool sensors_changed = false;
 103     bool has_jvmti_events = false;
 104     bool has_gc_notification_event = false;
 105     bool has_dcmd_notification_event = false;
 106     bool stringtable_work = false;
 107     bool symboltable_work = false;
 108     bool resolved_method_table_work = false;
 109     bool protection_domain_table_work = false;
 110     bool oopstorage_work = false;

 111     JvmtiDeferredEvent jvmti_event;
 112     {
 113       // Need state transition ThreadBlockInVM so that this thread
 114       // will be handled by safepoint correctly when this thread is
 115       // notified at a safepoint.
 116 
 117       // This ThreadBlockInVM object is not also considered to be
 118       // suspend-equivalent because ServiceThread is not visible to
 119       // external suspension.
 120 
 121       ThreadBlockInVM tbivm(jt);
 122 
 123       MonitorLocker ml(Service_lock, Mutex::_no_safepoint_check_flag);
 124       // Process all available work on each (outer) iteration, rather than
 125       // only the first recognized bit of work, to avoid frequently true early
 126       // tests from potentially starving later work.  Hence the use of
 127       // arithmetic-or to combine results; we don't want short-circuiting.
 128       while (((sensors_changed = LowMemoryDetector::has_pending_requests()) |
 129               (has_jvmti_events = JvmtiDeferredEventQueue::has_events()) |
 130               (has_gc_notification_event = GCNotifier::has_event()) |
 131               (has_dcmd_notification_event = DCmdFactory::has_pending_jmx_notification()) |
 132               (stringtable_work = StringTable::has_work()) |
 133               (symboltable_work = SymbolTable::has_work()) |
 134               (resolved_method_table_work = ResolvedMethodTable::has_work()) |
 135               (protection_domain_table_work = SystemDictionary::pd_cache_table()->has_work()) |
 136               (oopstorage_work = OopStorage::has_cleanup_work_and_reset()))
 137              == 0) {

 138         // Wait until notified that there is some work to do.
 139         ml.wait();



 140       }
 141 
 142       if (has_jvmti_events) {
 143         jvmti_event = JvmtiDeferredEventQueue::dequeue();
 144       }
 145     }
 146 
 147     if (stringtable_work) {
 148       StringTable::do_concurrent_work(jt);
 149     }
 150 
 151     if (symboltable_work) {
 152       SymbolTable::do_concurrent_work(jt);
 153     }
 154 
 155     if (has_jvmti_events) {
 156       jvmti_event.post();
 157     }
 158 
 159     if (sensors_changed) {


 161     }
 162 
 163     if(has_gc_notification_event) {
 164       GCNotifier::sendNotification(CHECK);
 165     }
 166 
 167     if(has_dcmd_notification_event) {
 168       DCmdFactory::send_notification(CHECK);
 169     }
 170 
 171     if (resolved_method_table_work) {
 172       ResolvedMethodTable::do_concurrent_work(jt);
 173     }
 174 
 175     if (protection_domain_table_work) {
 176       SystemDictionary::pd_cache_table()->unlink();
 177     }
 178 
 179     if (oopstorage_work) {
 180       cleanup_oopstorages(oopstorages, oopstorage_count);

























 181     }
 182   }
 183 }
 184 
 185 bool ServiceThread::is_service_thread(Thread* thread) {
 186   return thread == _instance;
 187 }


  91 
  92 void ServiceThread::service_thread_entry(JavaThread* jt, TRAPS) {
  93   OopStorage* const oopstorages[] = {
  94     JNIHandles::global_handles(),
  95     JNIHandles::weak_global_handles(),
  96     StringTable::weak_storage(),
  97     SystemDictionary::vm_weak_oop_storage()
  98   };
  99   const size_t oopstorage_count = ARRAY_SIZE(oopstorages);
 100 
 101   while (true) {
 102     bool sensors_changed = false;
 103     bool has_jvmti_events = false;
 104     bool has_gc_notification_event = false;
 105     bool has_dcmd_notification_event = false;
 106     bool stringtable_work = false;
 107     bool symboltable_work = false;
 108     bool resolved_method_table_work = false;
 109     bool protection_domain_table_work = false;
 110     bool oopstorage_work = false;
 111     bool deflate_idle_monitors = false;
 112     JvmtiDeferredEvent jvmti_event;
 113     {
 114       // Need state transition ThreadBlockInVM so that this thread
 115       // will be handled by safepoint correctly when this thread is
 116       // notified at a safepoint.
 117 
 118       // This ThreadBlockInVM object is not also considered to be
 119       // suspend-equivalent because ServiceThread is not visible to
 120       // external suspension.
 121 
 122       ThreadBlockInVM tbivm(jt);
 123 
 124       MonitorLocker ml(Service_lock, Mutex::_no_safepoint_check_flag);
 125       // Process all available work on each (outer) iteration, rather than
 126       // only the first recognized bit of work, to avoid frequently true early
 127       // tests from potentially starving later work.  Hence the use of
 128       // arithmetic-or to combine results; we don't want short-circuiting.
 129       while (((sensors_changed = LowMemoryDetector::has_pending_requests()) |
 130               (has_jvmti_events = JvmtiDeferredEventQueue::has_events()) |
 131               (has_gc_notification_event = GCNotifier::has_event()) |
 132               (has_dcmd_notification_event = DCmdFactory::has_pending_jmx_notification()) |
 133               (stringtable_work = StringTable::has_work()) |
 134               (symboltable_work = SymbolTable::has_work()) |
 135               (resolved_method_table_work = ResolvedMethodTable::has_work()) |
 136               (protection_domain_table_work = SystemDictionary::pd_cache_table()->has_work()) |
 137               (oopstorage_work = OopStorage::has_cleanup_work_and_reset()) |
 138               (deflate_idle_monitors = ObjectSynchronizer::is_async_deflation_needed())
 139              ) == 0) {
 140         // Wait until notified that there is some work to do.
 141         // If AsyncDeflateIdleMonitors, then we wait for
 142         // GuaranteedSafepointInterval so that is_async_deflation_needed()
 143         // is checked at the same interval.
 144         ml.wait(AsyncDeflateIdleMonitors ? GuaranteedSafepointInterval : 0);
 145       }
 146 
 147       if (has_jvmti_events) {
 148         jvmti_event = JvmtiDeferredEventQueue::dequeue();
 149       }
 150     }
 151 
 152     if (stringtable_work) {
 153       StringTable::do_concurrent_work(jt);
 154     }
 155 
 156     if (symboltable_work) {
 157       SymbolTable::do_concurrent_work(jt);
 158     }
 159 
 160     if (has_jvmti_events) {
 161       jvmti_event.post();
 162     }
 163 
 164     if (sensors_changed) {


 166     }
 167 
 168     if(has_gc_notification_event) {
 169       GCNotifier::sendNotification(CHECK);
 170     }
 171 
 172     if(has_dcmd_notification_event) {
 173       DCmdFactory::send_notification(CHECK);
 174     }
 175 
 176     if (resolved_method_table_work) {
 177       ResolvedMethodTable::do_concurrent_work(jt);
 178     }
 179 
 180     if (protection_domain_table_work) {
 181       SystemDictionary::pd_cache_table()->unlink();
 182     }
 183 
 184     if (oopstorage_work) {
 185       cleanup_oopstorages(oopstorages, oopstorage_count);
 186     }
 187 
 188     if (deflate_idle_monitors) {
 189       // Deflate any global idle monitors.
 190       ObjectSynchronizer::deflate_global_idle_monitors_using_JT();
 191 
 192       // deflate_per_thread_idle_monitors_using_JT() is called by
 193       // each JavaThread from ObjectSynchronizer::omAlloc() as needed.
 194       int count = 0;
 195       for (JavaThreadIteratorWithHandle jtiwh; JavaThread *jt = jtiwh.next(); ) {
 196         if (jt->omInUseCount > 0) {
 197           // This JavaThread is using monitors so mark it.
 198           jt->omShouldDeflateIdleMonitors = true;
 199           count++;
 200         }
 201       }
 202       if (count > 0) {
 203         log_debug(monitorinflation)("requesting async deflation of idle monitors for %d thread(s).", count);
 204       }
 205       // The ServiceThread's async deflation request has been processed.
 206       ObjectSynchronizer::set_is_async_deflation_requested(false);
 207 
 208       // The global in-use list was handled above, but the request won't
 209       // be complete until the JavaThreads have handled their in-use
 210       // lists. This is the nature of an async deflation request.
 211     }
 212   }
 213 }
 214 
 215 bool ServiceThread::is_service_thread(Thread* thread) {
 216   return thread == _instance;
 217 }
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