void GangWorker::loop() {
  int previous_sequence_number = 0;
  Monitor* gang_monitor = gang()->monitor();
  for ( ; /* !terminate() */; ) {
    WorkData data;
    int part;  // Initialized below.
    {
      // Grab the gang mutex.
      MutexLocker ml(gang_monitor);
      // Wait for something to do.
      // Polling outside the while { wait } avoids missed notifies
      // in the outer loop.
      gang()->internal_worker_poll(&data);
      if (TraceWorkGang) {
        tty->print("Polled outside for work in gang %s worker %d",
                   gang()->name(), id());
        tty->print("  terminate: %s",
                   data.terminate() ? "true" : "false");
        tty->print("  sequence: %d (prev: %d)",
                   data.sequence_number(), previous_sequence_number);
        if (data.task() != NULL) {
          tty->print("  task: %s", data.task()->name());
        } else {
          tty->print("  task: NULL");
        }
        tty->cr();
      }
      for ( ; /* break or return */; ) {
        // Terminate if requested.
        if (data.terminate()) {
          gang()->internal_note_finish();
          gang_monitor->notify_all();
          return;
        }
        // Check for new work.
        if ((data.task() != NULL) &&
            (data.sequence_number() != previous_sequence_number)) {
          if (gang()->needs_more_workers()) {
            gang()->internal_note_start();
            gang_monitor->notify_all();
            part = gang()->started_workers() - 1;
            break;
          }
        }
        // Nothing to do.
        gang_monitor->wait(/* no_safepoint_check */ true);
        gang()->internal_worker_poll(&data);
        if (TraceWorkGang) {
          tty->print("Polled inside for work in gang %s worker %d",
                     gang()->name(), id());
          tty->print("  terminate: %s",
                     data.terminate() ? "true" : "false");
          tty->print("  sequence: %d (prev: %d)",
                     data.sequence_number(), previous_sequence_number);
          if (data.task() != NULL) {
            tty->print("  task: %s", data.task()->name());
          } else {
            tty->print("  task: NULL");
          }
          tty->cr();
        }
      }
      // Drop gang mutex.
    }
    if (TraceWorkGang) {
      tty->print("Work for work gang %s id %d task %s part %d",
                 gang()->name(), id(), data.task()->name(), part);
    }
    assert(data.task() != NULL, "Got null task");
    data.task()->work(part);
    {
      if (TraceWorkGang) {
        tty->print("Finish for work gang %s id %d task %s part %d",
                   gang()->name(), id(), data.task()->name(), part);
      }
      // Grab the gang mutex.
      MutexLocker ml(gang_monitor);
      gang()->internal_note_finish();
      // Tell the gang you are done.
      gang_monitor->notify_all();
      // Drop the gang mutex.
    }
    previous_sequence_number = data.sequence_number();
  }
}
///////////////////////////////
// YieldingFlexibleGangWorker
///////////////////////////////
void YieldingFlexibleGangWorker::loop() {
  int previous_sequence_number = 0;
  Monitor* gang_monitor = gang()->monitor();
  MutexLockerEx ml(gang_monitor, Mutex::_no_safepoint_check_flag);
  WorkData data;
  int id;
  while (true) {
    // Check if there is work to do or if we have been asked
    // to terminate
    gang()->internal_worker_poll(&data);
    if (data.terminate()) {
      // We have been asked to terminate.
      assert(gang()->task() == NULL, "No task binding");
      // set_status(TERMINATED);
      return;
    } else if (data.task() != NULL &&
               data.sequence_number() != previous_sequence_number) {
      // There is work to be done.
      // First check if we need to become active or if there
      // are already the requisite number of workers
      if (gang()->started_workers() == yf_gang()->active_workers()) {
        // There are already enough workers, we do not need to
        // to run; fall through and wait on monitor.
      } else {
        // We need to pitch in and do the work.
        assert(gang()->started_workers() < yf_gang()->active_workers(),
               "Unexpected state");
        id = gang()->started_workers();
        gang()->internal_note_start();
        // Now, release the gang mutex and do the work.
        {
          MutexUnlockerEx mul(gang_monitor, Mutex::_no_safepoint_check_flag);
          data.task()->work(id);   // This might include yielding
        }
        // Reacquire monitor and note completion of this worker
        gang()->internal_note_finish();
        // Update status of task based on whether all workers have
        // finished or some have yielded
        assert(data.task() == gang()->task(), "Confused task binding");
        if (gang()->finished_workers() == yf_gang()->active_workers()) {
          switch (data.yf_task()->status()) {
            case ABORTING: {
              data.yf_task()->set_status(ABORTED);
              break;
            }
            case ACTIVE:
            case COMPLETING: {
              data.yf_task()->set_status(COMPLETED);
              break;
            }
            default:
              ShouldNotReachHere();
          }
          gang_monitor->notify_all();  // Notify overseer
        } else { // at least one worker is still working or yielded
          assert(gang()->finished_workers() < yf_gang()->active_workers(),
                 "Counts inconsistent");
          switch (data.yf_task()->status()) {
            case ACTIVE: {
              // first, but not only thread to complete
              data.yf_task()->set_status(COMPLETING);
              break;
            }
            case YIELDING: {
              if (gang()->finished_workers() + yf_gang()->yielded_workers()
                  == yf_gang()->active_workers()) {
                data.yf_task()->set_status(YIELDED);
                gang_monitor->notify_all();  // notify overseer
              }
              break;
            }
            case ABORTING:
            case COMPLETING: {
              break; // nothing to do
            }
            default: // everything else: INACTIVE, YIELDED, ABORTED, COMPLETED
              ShouldNotReachHere();
          }
        }
      }
    }
    // Remember the sequence number
    previous_sequence_number = data.sequence_number();
    // Wait for more work
    gang_monitor->wait(Mutex::_no_safepoint_check_flag);
  }
}
Beispiel #3
0
void GangWorker::run() {
  this->initialize_thread_local_storage();
  assert(_gang != NULL, "No gang to run in");
  Monitor* gang_monitor = gang()->monitor();
  os::set_priority(this, MaxPriority);
  if (TraceWorkGang) {
    tty->print_cr("Running gang worker for gang %s id %d",
		  gang()->name(), id());
  }
  int previous_sequence_number = 0;
  // The VM thread should not execute here because MutexLocker's are used
  // as (opposed to MutexLockerEx's).
  assert(!Thread::current()->is_VM_thread(), "VM thread should not be part"
	 " of a work gang");
  for ( ; /* !terminate() */; ) {
    WorkData data;
    int part;  // Initialized below.
    {
      // Grab the gang mutex.
      MutexLocker ml(gang_monitor);
      // Wait for something to do.
      // Polling outside the while { wait } avoids missed notifies
      // in the outer loop.
      gang()->internal_worker_poll(&data);
      if (TraceWorkGang) {
	tty->print("Polled outside for work in gang %s worker %d",
		   gang()->name(), id());
	tty->print("  terminate: %s",
		   data.terminate() ? "true" : "false");
	tty->print("  sequence: %d (prev: %d)",
		   data.sequence_number(), previous_sequence_number);
	if (data.task() != NULL) {
	  tty->print("  task: %s", data.task()->name());
	} else {
	  tty->print("  task: NULL");
	}
	tty->cr();
      }
      for ( ; /* break or return */; ) {
	// Terminate if requested.
	if (data.terminate()) {
	  gang()->internal_note_finish();
	  gang_monitor->notify_all();
	  return;
	}
	// Check for new work.
	if ((data.task() != NULL) &&
	    (data.sequence_number() != previous_sequence_number)) {
	  gang()->internal_note_start();
	  gang_monitor->notify_all();
	  part = gang()->started_workers() - 1;
	  break;
	}
	// Nothing to do.
	gang_monitor->wait(/* no_safepoint_check */ true);
	gang()->internal_worker_poll(&data);
	if (TraceWorkGang) {
	  tty->print("Polled inside for work in gang %s worker %d",
		     gang()->name(), id());
	  tty->print("  terminate: %s",
		     data.terminate() ? "true" : "false");
	  tty->print("  sequence: %d (prev: %d)",
		     data.sequence_number(), previous_sequence_number);
	  if (data.task() != NULL) {
	    tty->print("  task: %s", data.task()->name());
	  } else {
	    tty->print("  task: NULL");
	  }
	  tty->cr();
	}
      }
      // Drop gang mutex.
    }
    if (TraceWorkGang) {
      tty->print("Work for work gang %s id %d task %s part %d",
		 gang()->name(), id(), data.task()->name(), part);
    }
    assert(data.task() != NULL, "Got null task");
    data.task()->work(part);
    {
      if (TraceWorkGang) {
	tty->print("Finish for work gang %s id %d task %s part %d",
		   gang()->name(), id(), data.task()->name(), part);
      }
      // Grab the gang mutex.
      MutexLocker ml(gang_monitor);
      gang()->internal_note_finish();
      // Tell the gang you are done.
      gang_monitor->notify_all();
      // Drop the gang mutex.
    }
    previous_sequence_number = data.sequence_number();
  }
}