--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/runtime/task.cpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,131 @@
+/*
+ * Copyright 1997-2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+# include "incls/_precompiled.incl"
+# include "incls/_task.cpp.incl"
+
+int PeriodicTask::_num_tasks = 0;
+PeriodicTask* PeriodicTask::_tasks[PeriodicTask::max_tasks];
+#ifndef PRODUCT
+elapsedTimer PeriodicTask::_timer;
+int PeriodicTask::_intervalHistogram[PeriodicTask::max_interval];
+int PeriodicTask::_ticks;
+
+void PeriodicTask::print_intervals() {
+  if (ProfilerCheckIntervals) {
+    for (int i = 0; i < PeriodicTask::max_interval; i++) {
+      int n = _intervalHistogram[i];
+      if (n > 0) tty->print_cr("%3d: %5d (%4.1f%%)", i, n, 100.0 * n / _ticks);
+    }
+  }
+}
+#endif
+
+void PeriodicTask::real_time_tick(size_t delay_time) {
+#ifndef PRODUCT
+  if (ProfilerCheckIntervals) {
+    _ticks++;
+    _timer.stop();
+    int ms = (int)(_timer.seconds() * 1000.0);
+    _timer.reset();
+    _timer.start();
+    if (ms >= PeriodicTask::max_interval) ms = PeriodicTask::max_interval - 1;
+    _intervalHistogram[ms]++;
+  }
+#endif
+  int orig_num_tasks = _num_tasks;
+  for(int index = 0; index < _num_tasks; index++) {
+    _tasks[index]->execute_if_pending(delay_time);
+    if (_num_tasks < orig_num_tasks) { // task dis-enrolled itself
+      index--;  // re-do current slot as it has changed
+      orig_num_tasks = _num_tasks;
+    }
+  }
+}
+
+
+PeriodicTask::PeriodicTask(size_t interval_time) :
+  _counter(0), _interval(interval_time) {
+  assert(is_init_completed(), "Periodic tasks should not start during VM initialization");
+  // Sanity check the interval time
+  assert(_interval >= PeriodicTask::min_interval &&
+         _interval <= PeriodicTask::max_interval &&
+         _interval %  PeriodicTask::interval_gran == 0,
+              "improper PeriodicTask interval time");
+}
+
+PeriodicTask::~PeriodicTask() {
+  if (is_enrolled())
+    disenroll();
+}
+
+bool PeriodicTask::is_enrolled() const {
+  for(int index = 0; index < _num_tasks; index++)
+    if (_tasks[index] == this) return true;
+  return false;
+}
+
+void PeriodicTask::enroll() {
+  assert(WatcherThread::watcher_thread() == NULL, "dynamic enrollment of tasks not yet supported");
+
+  if (_num_tasks == PeriodicTask::max_tasks)
+    fatal("Overflow in PeriodicTask table");
+  _tasks[_num_tasks++] = this;
+}
+
+void PeriodicTask::disenroll() {
+  assert(WatcherThread::watcher_thread() == NULL ||
+         Thread::current() == WatcherThread::watcher_thread(),
+         "dynamic disenrollment currently only handled from WatcherThread from within task() method");
+
+  int index;
+  for(index = 0; index < _num_tasks && _tasks[index] != this; index++);
+  if (index == _num_tasks) return;
+  _num_tasks--;
+  for (; index < _num_tasks; index++) {
+    _tasks[index] = _tasks[index+1];
+  }
+}
+
+TimeMillisUpdateTask* TimeMillisUpdateTask::_task = NULL;
+
+void TimeMillisUpdateTask::task() {
+  os::update_global_time();
+}
+
+void TimeMillisUpdateTask::engage() {
+  assert(_task == NULL, "init twice?");
+  os::update_global_time(); // initial update
+  os::enable_global_time();
+  _task = new TimeMillisUpdateTask(CacheTimeMillisGranularity);
+  _task->enroll();
+}
+
+void TimeMillisUpdateTask::disengage() {
+  assert(_task != NULL, "uninit twice?");
+  os::disable_global_time();
+  _task->disenroll();
+  delete _task;
+  _task = NULL;
+}