1 /*
2 BAREOS® - Backup Archiving REcovery Open Sourced
3
4 Copyright (C) 2002-2011 Free Software Foundation Europe e.V.
5 Copyright (C) 2019-2019 Bareos GmbH & Co. KG
6
7 This program is Free Software; you can redistribute it and/or
8 modify it under the terms of version three of the GNU Affero General Public
9 License as published by the Free Software Foundation and included
10 in the file LICENSE.
11
12 This program is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Affero General Public License for more details.
16
17 You should have received a copy of the GNU Affero General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
20 02110-1301, USA.
21 */
22
23 #include "include/bareos.h"
24 #include "lib/timer_thread.h"
25 #include "include/jcr.h"
26 #include "lib/thread_specific_data.h"
27 #include "include/make_unique.h"
28
29 #include <atomic>
30 #include <algorithm>
31 #include <cassert>
32 #include <chrono>
33 #include <condition_variable>
34 #include <mutex>
35 #include <thread>
36
37 namespace TimerThread {
38
39 /* clang-format off */
40 static std::chrono::milliseconds idle_timeout_interval_milliseconds(60 * 1000);
41 static std::atomic<std::time_t> calendar_time_on_last_timer_run(time(nullptr));
42 /* clang-format on */
43
44 static std::mutex timer_sleep_mutex;
45 static std::condition_variable timer_sleep_condition;
46 static bool wakeup_event_occured = false;
47
48 static void TimerThread(void);
49
50 enum class TimerThreadState
51 {
52 IS_NOT_INITIALZED,
53 IS_STARTING,
54 IS_RUNNING,
55 IS_SHUTTING_DOWN,
56 IS_SHUT_DOWN
57 };
58
59 static std::atomic<TimerThreadState> timer_thread_state(
60 TimerThreadState::IS_NOT_INITIALZED);
61 static std::atomic<bool> quit_timer_thread(false);
62
63 static std::unique_ptr<std::thread> timer_thread;
64 static std::mutex controlled_items_list_mutex;
65
66 static std::vector<TimerThread::Timer*> controlled_items_list;
67
Start(void)68 bool Start(void)
69 {
70 if (timer_thread_state != TimerThreadState::IS_NOT_INITIALZED
71 && timer_thread_state != TimerThreadState::IS_SHUT_DOWN) {
72 return false;
73 }
74
75 Dmsg0(800, "Starting timer thread\n");
76
77 quit_timer_thread = false;
78 timer_thread = std::make_unique<std::thread>(TimerThread);
79
80 int timeout = 0;
81 while (timer_thread_state.load() != TimerThreadState::IS_RUNNING
82 && ++timeout < 2000) {
83 std::this_thread::sleep_for(std::chrono::milliseconds(1));
84 }
85
86 return true;
87 }
88
WakeTimer()89 static void WakeTimer()
90 {
91 std::lock_guard<std::mutex> l(timer_sleep_mutex);
92 wakeup_event_occured = true;
93 timer_sleep_condition.notify_one();
94 }
95
Stop(void)96 void Stop(void)
97 {
98 if (timer_thread_state != TimerThreadState::IS_RUNNING) { return; }
99
100 quit_timer_thread = true;
101 WakeTimer();
102
103 timer_thread->join();
104 }
105
NewTimer(void)106 TimerThread::Timer* NewTimer(void)
107 {
108 TimerThread::Timer* t = new TimerThread::Timer;
109
110 std::lock_guard<std::mutex> l(controlled_items_list_mutex);
111 controlled_items_list.push_back(t);
112
113 if (timer_thread_state != TimerThreadState::IS_RUNNING) { Start(); }
114
115 return t;
116 }
117
RegisterTimer(TimerThread::Timer * t)118 bool RegisterTimer(TimerThread::Timer* t)
119 {
120 assert(t->user_callback != nullptr);
121
122 TimerThread::Timer wd_copy;
123
124 {
125 std::lock_guard<std::mutex> l(controlled_items_list_mutex);
126
127 if (std::find(controlled_items_list.begin(), controlled_items_list.end(), t)
128 == controlled_items_list.end()) {
129 return false;
130 }
131
132 t->scheduled_run_timepoint = std::chrono::steady_clock::now() + t->interval;
133 t->is_active = true;
134
135 wd_copy = *t;
136 }
137
138 Dmsg3(800, "Registered timer interval %d%s\n", wd_copy.interval,
139 wd_copy.single_shot ? " one shot" : "");
140
141 WakeTimer();
142
143 return true;
144 }
145
UnregisterTimer(TimerThread::Timer * t)146 bool UnregisterTimer(TimerThread::Timer* t)
147 {
148 std::lock_guard<std::mutex> l(controlled_items_list_mutex);
149
150 auto pos = std::find(controlled_items_list.begin(),
151 controlled_items_list.end(), t);
152
153 if (pos != controlled_items_list.end()) {
154 if ((*pos)->user_destructor) { (*pos)->user_destructor((*pos)); }
155 delete (*pos);
156 controlled_items_list.erase(pos);
157 Dmsg1(800, "Unregistered timer %p\n", t);
158 return true;
159 } else {
160 Dmsg1(800, "Failed to unregister timer %p\n", t);
161 return false;
162 }
163 }
164
IsRegisteredTimer(const TimerThread::Timer * t)165 bool IsRegisteredTimer(const TimerThread::Timer* t)
166 {
167 std::lock_guard<std::mutex> l(controlled_items_list_mutex);
168
169 auto pos = std::find(controlled_items_list.begin(),
170 controlled_items_list.end(), t);
171
172 return pos != controlled_items_list.end();
173 }
174
Cleanup()175 static void Cleanup()
176 {
177 std::lock_guard<std::mutex> l(controlled_items_list_mutex);
178
179 for (auto p : controlled_items_list) {
180 if (p->user_destructor) { p->user_destructor(p); }
181 delete p;
182 }
183 controlled_items_list.clear();
184 }
185
SleepUntil(std::chrono::steady_clock::time_point next_timer_run)186 static void SleepUntil(std::chrono::steady_clock::time_point next_timer_run)
187 {
188 std::unique_lock<std::mutex> l(timer_sleep_mutex);
189 timer_sleep_condition.wait_until(l, next_timer_run,
190 []() { return wakeup_event_occured; });
191 wakeup_event_occured = false;
192 }
193
LogMessage(TimerThread::Timer * p)194 static void LogMessage(TimerThread::Timer* p)
195 {
196 Dmsg2(3400, "Timer callback p=0x%p scheduled_run_timepoint=%d\n", p,
197 p->scheduled_run_timepoint);
198 }
199
RunOneItem(TimerThread::Timer * p,std::chrono::steady_clock::time_point & next_timer_run)200 static bool RunOneItem(TimerThread::Timer* p,
201 std::chrono::steady_clock::time_point& next_timer_run)
202 {
203 std::chrono::time_point<std::chrono::steady_clock> last_timer_run_timepoint
204 = std::chrono::steady_clock::now();
205
206 bool remove_from_list = false;
207 if (p->is_active && last_timer_run_timepoint > p->scheduled_run_timepoint) {
208 LogMessage(p);
209 p->user_callback(p);
210 if (p->single_shot) {
211 if (p->user_destructor) { p->user_destructor(p); }
212 delete p;
213 remove_from_list = true;
214 } else {
215 p->scheduled_run_timepoint = last_timer_run_timepoint + p->interval;
216 }
217 }
218 next_timer_run = min(p->scheduled_run_timepoint, next_timer_run);
219 return remove_from_list;
220 }
221
RunAllItemsAndRemoveOneShotItems(std::chrono::steady_clock::time_point & next_timer_run)222 static void RunAllItemsAndRemoveOneShotItems(
223 std::chrono::steady_clock::time_point& next_timer_run)
224 {
225 std::unique_lock<std::mutex> l(controlled_items_list_mutex);
226
227 auto new_end_of_vector = std::remove_if( // one_shot items will be removed
228 controlled_items_list.begin(), controlled_items_list.end(),
229 [&next_timer_run](TimerThread::Timer* p) {
230 calendar_time_on_last_timer_run = time(nullptr);
231
232 return RunOneItem(p, next_timer_run);
233 });
234
235 controlled_items_list.erase(new_end_of_vector, controlled_items_list.end());
236 }
237
TimerThread(void)238 static void TimerThread(void)
239 {
240 SetJcrInThreadSpecificData(nullptr);
241
242 Dmsg0(800, "Timer thread started\n");
243 timer_thread_state = TimerThreadState::IS_RUNNING;
244
245 while (!quit_timer_thread) {
246 std::chrono::steady_clock::time_point next_timer_run
247 = std::chrono::steady_clock::now() + idle_timeout_interval_milliseconds;
248
249 RunAllItemsAndRemoveOneShotItems(next_timer_run);
250
251 SleepUntil(next_timer_run);
252 } // while (!quit_timer_thread)
253
254 Cleanup();
255 timer_thread_state = TimerThreadState::IS_SHUT_DOWN;
256 }
257
258 class TimerThreadGuard {
259 public:
260 TimerThreadGuard() = default;
~TimerThreadGuard()261 ~TimerThreadGuard()
262 {
263 if (timer_thread_state == TimerThreadState::IS_RUNNING) { Stop(); }
264 }
265 };
266
267 static TimerThreadGuard timer_thread_guard;
268
SetTimerIdleSleepTime(std::chrono::seconds time)269 void SetTimerIdleSleepTime(std::chrono::seconds time)
270 {
271 std::lock_guard<std::mutex> lg(controlled_items_list_mutex);
272 idle_timeout_interval_milliseconds = time;
273 }
274
CurrentThreadIsTimerThread()275 bool CurrentThreadIsTimerThread()
276 {
277 return (timer_thread_state == TimerThreadState::IS_RUNNING
278 && (std::this_thread::get_id() == timer_thread->get_id()));
279 }
280
GetCalenderTimeOnLastTimerThreadRun()281 std::time_t GetCalenderTimeOnLastTimerThreadRun()
282 {
283 return calendar_time_on_last_timer_run;
284 }
285
286 } // namespace TimerThread
287