duke@435: /*
duke@435:  * Copyright 1997-2007 Sun Microsystems, Inc.  All Rights Reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
duke@435:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435:  * CA 95054 USA or visit www.sun.com if you need additional information or
duke@435:  * have any questions.
duke@435:  *
duke@435:  */
duke@435: 
duke@435: # include "incls/_precompiled.incl"
duke@435: # include "incls/_task.cpp.incl"
duke@435: 
duke@435: int PeriodicTask::_num_tasks = 0;
duke@435: PeriodicTask* PeriodicTask::_tasks[PeriodicTask::max_tasks];
duke@435: #ifndef PRODUCT
duke@435: elapsedTimer PeriodicTask::_timer;
duke@435: int PeriodicTask::_intervalHistogram[PeriodicTask::max_interval];
duke@435: int PeriodicTask::_ticks;
duke@435: 
duke@435: void PeriodicTask::print_intervals() {
duke@435:   if (ProfilerCheckIntervals) {
duke@435:     for (int i = 0; i < PeriodicTask::max_interval; i++) {
duke@435:       int n = _intervalHistogram[i];
duke@435:       if (n > 0) tty->print_cr("%3d: %5d (%4.1f%%)", i, n, 100.0 * n / _ticks);
duke@435:     }
duke@435:   }
duke@435: }
duke@435: #endif
duke@435: 
duke@435: void PeriodicTask::real_time_tick(size_t delay_time) {
duke@435: #ifndef PRODUCT
duke@435:   if (ProfilerCheckIntervals) {
duke@435:     _ticks++;
duke@435:     _timer.stop();
duke@435:     int ms = (int)(_timer.seconds() * 1000.0);
duke@435:     _timer.reset();
duke@435:     _timer.start();
duke@435:     if (ms >= PeriodicTask::max_interval) ms = PeriodicTask::max_interval - 1;
duke@435:     _intervalHistogram[ms]++;
duke@435:   }
duke@435: #endif
duke@435:   int orig_num_tasks = _num_tasks;
duke@435:   for(int index = 0; index < _num_tasks; index++) {
duke@435:     _tasks[index]->execute_if_pending(delay_time);
duke@435:     if (_num_tasks < orig_num_tasks) { // task dis-enrolled itself
duke@435:       index--;  // re-do current slot as it has changed
duke@435:       orig_num_tasks = _num_tasks;
duke@435:     }
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: PeriodicTask::PeriodicTask(size_t interval_time) :
duke@435:   _counter(0), _interval(interval_time) {
duke@435:   assert(is_init_completed(), "Periodic tasks should not start during VM initialization");
duke@435:   // Sanity check the interval time
duke@435:   assert(_interval >= PeriodicTask::min_interval &&
duke@435:          _interval <= PeriodicTask::max_interval &&
duke@435:          _interval %  PeriodicTask::interval_gran == 0,
duke@435:               "improper PeriodicTask interval time");
duke@435: }
duke@435: 
duke@435: PeriodicTask::~PeriodicTask() {
duke@435:   if (is_enrolled())
duke@435:     disenroll();
duke@435: }
duke@435: 
duke@435: bool PeriodicTask::is_enrolled() const {
duke@435:   for(int index = 0; index < _num_tasks; index++)
duke@435:     if (_tasks[index] == this) return true;
duke@435:   return false;
duke@435: }
duke@435: 
duke@435: void PeriodicTask::enroll() {
duke@435:   assert(WatcherThread::watcher_thread() == NULL, "dynamic enrollment of tasks not yet supported");
duke@435: 
duke@435:   if (_num_tasks == PeriodicTask::max_tasks)
duke@435:     fatal("Overflow in PeriodicTask table");
duke@435:   _tasks[_num_tasks++] = this;
duke@435: }
duke@435: 
duke@435: void PeriodicTask::disenroll() {
duke@435:   assert(WatcherThread::watcher_thread() == NULL ||
duke@435:          Thread::current() == WatcherThread::watcher_thread(),
duke@435:          "dynamic disenrollment currently only handled from WatcherThread from within task() method");
duke@435: 
duke@435:   int index;
duke@435:   for(index = 0; index < _num_tasks && _tasks[index] != this; index++);
duke@435:   if (index == _num_tasks) return;
duke@435:   _num_tasks--;
duke@435:   for (; index < _num_tasks; index++) {
duke@435:     _tasks[index] = _tasks[index+1];
duke@435:   }
duke@435: }
duke@435: 
duke@435: TimeMillisUpdateTask* TimeMillisUpdateTask::_task = NULL;
duke@435: 
duke@435: void TimeMillisUpdateTask::task() {
duke@435:   os::update_global_time();
duke@435: }
duke@435: 
duke@435: void TimeMillisUpdateTask::engage() {
duke@435:   assert(_task == NULL, "init twice?");
duke@435:   os::update_global_time(); // initial update
duke@435:   os::enable_global_time();
duke@435:   _task = new TimeMillisUpdateTask(CacheTimeMillisGranularity);
duke@435:   _task->enroll();
duke@435: }
duke@435: 
duke@435: void TimeMillisUpdateTask::disengage() {
duke@435:   assert(_task != NULL, "uninit twice?");
duke@435:   os::disable_global_time();
duke@435:   _task->disenroll();
duke@435:   delete _task;
duke@435:   _task = NULL;
duke@435: }