duke@435: /*
sla@5237:  * Copyright (c) 1997, 2013, Oracle and/or its affiliates. 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:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
stefank@2314: #include "precompiled.hpp"
stefank@2314: #include "memory/allocation.hpp"
stefank@2314: #include "runtime/init.hpp"
stefank@2314: #include "runtime/task.hpp"
stefank@4299: #include "runtime/thread.inline.hpp"
stefank@2314: #include "runtime/timer.hpp"
stefank@2314: #ifdef TARGET_OS_FAMILY_linux
stefank@2314: # include "os_linux.inline.hpp"
stefank@2314: #endif
stefank@2314: #ifdef TARGET_OS_FAMILY_solaris
stefank@2314: # include "os_solaris.inline.hpp"
stefank@2314: #endif
stefank@2314: #ifdef TARGET_OS_FAMILY_windows
stefank@2314: # include "os_windows.inline.hpp"
stefank@2314: #endif
never@3156: #ifdef TARGET_OS_FAMILY_bsd
never@3156: # include "os_bsd.inline.hpp"
never@3156: #endif
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: 
rbackman@4250: void PeriodicTask::real_time_tick(int 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
rbackman@4250: 
rbackman@4250:   {
rbackman@4250:     MutexLockerEx ml(PeriodicTask_lock, Mutex::_no_safepoint_check_flag);
rbackman@4250:     int orig_num_tasks = _num_tasks;
rbackman@4250: 
rbackman@4250:     for(int index = 0; index < _num_tasks; index++) {
rbackman@4250:       _tasks[index]->execute_if_pending(delay_time);
rbackman@4250:       if (_num_tasks < orig_num_tasks) { // task dis-enrolled itself
rbackman@4250:         index--;  // re-do current slot as it has changed
rbackman@4250:         orig_num_tasks = _num_tasks;
rbackman@4250:       }
duke@435:     }
duke@435:   }
duke@435: }
duke@435: 
rbackman@4250: int PeriodicTask::time_to_wait() {
rbackman@4250:   MutexLockerEx ml(PeriodicTask_lock->owned_by_self() ?
rbackman@4250:                      NULL : PeriodicTask_lock, Mutex::_no_safepoint_check_flag);
rbackman@4250: 
rbackman@4250:   if (_num_tasks == 0) {
rbackman@4250:     return 0; // sleep until shutdown or a task is enrolled
rbackman@4250:   }
rbackman@4250: 
rbackman@4250:   int delay = _tasks[0]->time_to_next_interval();
rbackman@4250:   for (int index = 1; index < _num_tasks; index++) {
rbackman@4250:     delay = MIN2(delay, _tasks[index]->time_to_next_interval());
rbackman@4250:   }
rbackman@4250:   return delay;
rbackman@4250: }
rbackman@4250: 
duke@435: 
duke@435: PeriodicTask::PeriodicTask(size_t interval_time) :
rbackman@4250:   _counter(0), _interval((int) interval_time) {
duke@435:   // Sanity check the interval time
duke@435:   assert(_interval >= PeriodicTask::min_interval &&
duke@435:          _interval %  PeriodicTask::interval_gran == 0,
duke@435:               "improper PeriodicTask interval time");
duke@435: }
duke@435: 
duke@435: PeriodicTask::~PeriodicTask() {
rbackman@4250:   disenroll();
duke@435: }
duke@435: 
sla@5237: /* enroll could be called from a JavaThread, so we have to check for
sla@5237:  * safepoint when taking the lock to avoid deadlocking */
duke@435: void PeriodicTask::enroll() {
rbackman@4250:   MutexLockerEx ml(PeriodicTask_lock->owned_by_self() ?
sla@5237:                      NULL : PeriodicTask_lock);
duke@435: 
rbackman@4250:   if (_num_tasks == PeriodicTask::max_tasks) {
duke@435:     fatal("Overflow in PeriodicTask table");
rbackman@4250:   }
duke@435:   _tasks[_num_tasks++] = this;
rbackman@4250: 
rbackman@4250:   WatcherThread* thread = WatcherThread::watcher_thread();
rbackman@4250:   if (thread) {
rbackman@4250:     thread->unpark();
rbackman@4250:   } else {
rbackman@4250:     WatcherThread::start();
rbackman@4250:   }
duke@435: }
duke@435: 
sla@5237: /* disenroll could be called from a JavaThread, so we have to check for
sla@5237:  * safepoint when taking the lock to avoid deadlocking */
duke@435: void PeriodicTask::disenroll() {
rbackman@4250:   MutexLockerEx ml(PeriodicTask_lock->owned_by_self() ?
sla@5237:                      NULL : PeriodicTask_lock);
duke@435: 
duke@435:   int index;
rbackman@4250:   for(index = 0; index < _num_tasks && _tasks[index] != this; index++)
rbackman@4250:     ;
rbackman@4250: 
rbackman@4250:   if (index == _num_tasks) {
rbackman@4250:     return;
rbackman@4250:   }
rbackman@4250: 
duke@435:   _num_tasks--;
rbackman@4250: 
duke@435:   for (; index < _num_tasks; index++) {
duke@435:     _tasks[index] = _tasks[index+1];
duke@435:   }
duke@435: }