1 /* 2 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "memory/allocation.hpp" 27 #include "runtime/init.hpp" 28 #include "runtime/task.hpp" 29 #include "runtime/timer.hpp" 30 #ifdef TARGET_OS_FAMILY_linux 31 # include "os_linux.inline.hpp" 32 # include "thread_linux.inline.hpp" 33 #endif 34 #ifdef TARGET_OS_FAMILY_solaris 35 # include "os_solaris.inline.hpp" 36 # include "thread_solaris.inline.hpp" 37 #endif 38 #ifdef TARGET_OS_FAMILY_windows 39 # include "os_windows.inline.hpp" 40 # include "thread_windows.inline.hpp" 41 #endif 42 43 int PeriodicTask::_num_tasks = 0; 44 PeriodicTask* PeriodicTask::_tasks[PeriodicTask::max_tasks]; 45 #ifndef PRODUCT 46 elapsedTimer PeriodicTask::_timer; 47 int PeriodicTask::_intervalHistogram[PeriodicTask::max_interval]; 48 int PeriodicTask::_ticks; 49 50 void PeriodicTask::print_intervals() { 51 if (ProfilerCheckIntervals) { 52 for (int i = 0; i < PeriodicTask::max_interval; i++) { 53 int n = _intervalHistogram[i]; 54 if (n > 0) tty->print_cr("%3d: %5d (%4.1f%%)", i, n, 100.0 * n / _ticks); 55 } 56 } 57 } 58 #endif 59 60 void PeriodicTask::real_time_tick(size_t delay_time) { 61 #ifndef PRODUCT 62 if (ProfilerCheckIntervals) { 63 _ticks++; 64 _timer.stop(); 65 int ms = (int)(_timer.seconds() * 1000.0); 66 _timer.reset(); 67 _timer.start(); 68 if (ms >= PeriodicTask::max_interval) ms = PeriodicTask::max_interval - 1; 69 _intervalHistogram[ms]++; 70 } 71 #endif 72 int orig_num_tasks = _num_tasks; 73 for(int index = 0; index < _num_tasks; index++) { 74 _tasks[index]->execute_if_pending(delay_time); 75 if (_num_tasks < orig_num_tasks) { // task dis-enrolled itself 76 index--; // re-do current slot as it has changed 77 orig_num_tasks = _num_tasks; 78 } 79 } 80 } 81 82 83 PeriodicTask::PeriodicTask(size_t interval_time) : 84 _counter(0), _interval(interval_time) { 85 // Sanity check the interval time 86 assert(_interval >= PeriodicTask::min_interval && 87 _interval <= PeriodicTask::max_interval && 88 _interval % PeriodicTask::interval_gran == 0, 89 "improper PeriodicTask interval time"); 90 } 91 92 PeriodicTask::~PeriodicTask() { 93 if (is_enrolled()) 94 disenroll(); 95 } 96 97 bool PeriodicTask::is_enrolled() const { 98 for(int index = 0; index < _num_tasks; index++) 99 if (_tasks[index] == this) return true; 100 return false; 101 } 102 103 void PeriodicTask::enroll() { 104 assert(WatcherThread::watcher_thread() == NULL, "dynamic enrollment of tasks not yet supported"); 105 106 if (_num_tasks == PeriodicTask::max_tasks) 107 fatal("Overflow in PeriodicTask table"); 108 _tasks[_num_tasks++] = this; 109 } 110 111 void PeriodicTask::disenroll() { 112 assert(WatcherThread::watcher_thread() == NULL || 113 Thread::current() == WatcherThread::watcher_thread(), 114 "dynamic disenrollment currently only handled from WatcherThread from within task() method"); 115 116 int index; 117 for(index = 0; index < _num_tasks && _tasks[index] != this; index++); 118 if (index == _num_tasks) return; 119 _num_tasks--; 120 for (; index < _num_tasks; index++) { 121 _tasks[index] = _tasks[index+1]; 122 } 123 }