aoqi@0: /*
aoqi@0:  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #include "precompiled.hpp"
aoqi@0: #include "memory/allocation.hpp"
aoqi@0: #include "runtime/init.hpp"
aoqi@0: #include "runtime/task.hpp"
aoqi@0: #include "runtime/thread.inline.hpp"
aoqi@0: #include "runtime/timer.hpp"
aoqi@0: #ifdef TARGET_OS_FAMILY_linux
aoqi@0: # include "os_linux.inline.hpp"
aoqi@0: #endif
aoqi@0: #ifdef TARGET_OS_FAMILY_solaris
aoqi@0: # include "os_solaris.inline.hpp"
aoqi@0: #endif
aoqi@0: #ifdef TARGET_OS_FAMILY_windows
aoqi@0: # include "os_windows.inline.hpp"
aoqi@0: #endif
aoqi@0: #ifdef TARGET_OS_FAMILY_bsd
aoqi@0: # include "os_bsd.inline.hpp"
aoqi@0: #endif
aoqi@0: 
aoqi@0: int PeriodicTask::_num_tasks = 0;
aoqi@0: PeriodicTask* PeriodicTask::_tasks[PeriodicTask::max_tasks];
aoqi@0: #ifndef PRODUCT
aoqi@0: elapsedTimer PeriodicTask::_timer;
aoqi@0: int PeriodicTask::_intervalHistogram[PeriodicTask::max_interval];
aoqi@0: int PeriodicTask::_ticks;
aoqi@0: 
aoqi@0: void PeriodicTask::print_intervals() {
aoqi@0:   if (ProfilerCheckIntervals) {
aoqi@0:     for (int i = 0; i < PeriodicTask::max_interval; i++) {
aoqi@0:       int n = _intervalHistogram[i];
aoqi@0:       if (n > 0) tty->print_cr("%3d: %5d (%4.1f%%)", i, n, 100.0 * n / _ticks);
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: #endif
aoqi@0: 
aoqi@0: void PeriodicTask::real_time_tick(int delay_time) {
aoqi@0: #ifndef PRODUCT
aoqi@0:   if (ProfilerCheckIntervals) {
aoqi@0:     _ticks++;
aoqi@0:     _timer.stop();
aoqi@0:     int ms = (int)(_timer.seconds() * 1000.0);
aoqi@0:     _timer.reset();
aoqi@0:     _timer.start();
aoqi@0:     if (ms >= PeriodicTask::max_interval) ms = PeriodicTask::max_interval - 1;
aoqi@0:     _intervalHistogram[ms]++;
aoqi@0:   }
aoqi@0: #endif
aoqi@0: 
aoqi@0:   {
aoqi@0:     MutexLockerEx ml(PeriodicTask_lock, Mutex::_no_safepoint_check_flag);
aoqi@0:     int orig_num_tasks = _num_tasks;
aoqi@0: 
aoqi@0:     for(int index = 0; index < _num_tasks; index++) {
aoqi@0:       _tasks[index]->execute_if_pending(delay_time);
aoqi@0:       if (_num_tasks < orig_num_tasks) { // task dis-enrolled itself
aoqi@0:         index--;  // re-do current slot as it has changed
aoqi@0:         orig_num_tasks = _num_tasks;
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: int PeriodicTask::time_to_wait() {
aoqi@0:   MutexLockerEx ml(PeriodicTask_lock->owned_by_self() ?
aoqi@0:                      NULL : PeriodicTask_lock, Mutex::_no_safepoint_check_flag);
aoqi@0: 
aoqi@0:   if (_num_tasks == 0) {
aoqi@0:     return 0; // sleep until shutdown or a task is enrolled
aoqi@0:   }
aoqi@0: 
aoqi@0:   int delay = _tasks[0]->time_to_next_interval();
aoqi@0:   for (int index = 1; index < _num_tasks; index++) {
aoqi@0:     delay = MIN2(delay, _tasks[index]->time_to_next_interval());
aoqi@0:   }
aoqi@0:   return delay;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: PeriodicTask::PeriodicTask(size_t interval_time) :
aoqi@0:   _counter(0), _interval((int) interval_time) {
aoqi@0:   // Sanity check the interval time
aoqi@0:   assert(_interval >= PeriodicTask::min_interval &&
aoqi@0:          _interval %  PeriodicTask::interval_gran == 0,
aoqi@0:               "improper PeriodicTask interval time");
aoqi@0: }
aoqi@0: 
aoqi@0: PeriodicTask::~PeriodicTask() {
aoqi@0:   disenroll();
aoqi@0: }
aoqi@0: 
aoqi@0: /* enroll could be called from a JavaThread, so we have to check for
aoqi@0:  * safepoint when taking the lock to avoid deadlocking */
aoqi@0: void PeriodicTask::enroll() {
aoqi@0:   MutexLockerEx ml(PeriodicTask_lock->owned_by_self() ?
aoqi@0:                      NULL : PeriodicTask_lock);
aoqi@0: 
aoqi@0:   if (_num_tasks == PeriodicTask::max_tasks) {
aoqi@0:     fatal("Overflow in PeriodicTask table");
aoqi@0:   }
aoqi@0:   _tasks[_num_tasks++] = this;
aoqi@0: 
aoqi@0:   WatcherThread* thread = WatcherThread::watcher_thread();
aoqi@0:   if (thread) {
aoqi@0:     thread->unpark();
aoqi@0:   } else {
aoqi@0:     WatcherThread::start();
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: /* disenroll could be called from a JavaThread, so we have to check for
aoqi@0:  * safepoint when taking the lock to avoid deadlocking */
aoqi@0: void PeriodicTask::disenroll() {
aoqi@0:   MutexLockerEx ml(PeriodicTask_lock->owned_by_self() ?
aoqi@0:                      NULL : PeriodicTask_lock);
aoqi@0: 
aoqi@0:   int index;
aoqi@0:   for(index = 0; index < _num_tasks && _tasks[index] != this; index++)
aoqi@0:     ;
aoqi@0: 
aoqi@0:   if (index == _num_tasks) {
aoqi@0:     return;
aoqi@0:   }
aoqi@0: 
aoqi@0:   _num_tasks--;
aoqi@0: 
aoqi@0:   for (; index < _num_tasks; index++) {
aoqi@0:     _tasks[index] = _tasks[index+1];
aoqi@0:   }
aoqi@0: }