1 /*
2 * Copyright (C) 2013 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <pthread.h>
18 #include <sched.h>
19 #include <sys/resource.h>
20
21 #include <cutils/sched_policy.h>
22 #include <log/log.h>
23 #include <system/thread_defs.h>
24
25 #include "EventControlThread.h"
26
27 namespace android {
28
29 EventControlThread::~EventControlThread() = default;
30
31 namespace impl {
32
EventControlThread(EventControlThread::SetVSyncEnabledFunction function)33 EventControlThread::EventControlThread(EventControlThread::SetVSyncEnabledFunction function)
34 : mSetVSyncEnabled(function) {
35 pthread_setname_np(mThread.native_handle(), "EventControlThread");
36
37 pid_t tid = pthread_gettid_np(mThread.native_handle());
38 setpriority(PRIO_PROCESS, tid, ANDROID_PRIORITY_URGENT_DISPLAY);
39 set_sched_policy(tid, SP_FOREGROUND);
40 }
41
~EventControlThread()42 EventControlThread::~EventControlThread() {
43 {
44 std::lock_guard<std::mutex> lock(mMutex);
45 mKeepRunning = false;
46 mCondition.notify_all();
47 }
48 mThread.join();
49 }
50
setVsyncEnabled(bool enabled)51 void EventControlThread::setVsyncEnabled(bool enabled) {
52 std::lock_guard<std::mutex> lock(mMutex);
53 mVsyncEnabled = enabled;
54 mCondition.notify_all();
55 }
56
57 // Unfortunately std::unique_lock gives warnings with -Wthread-safety
threadMain()58 void EventControlThread::threadMain() NO_THREAD_SAFETY_ANALYSIS {
59 auto keepRunning = true;
60 auto currentVsyncEnabled = false;
61
62 while (keepRunning) {
63 mSetVSyncEnabled(currentVsyncEnabled);
64
65 std::unique_lock<std::mutex> lock(mMutex);
66 mCondition.wait(lock, [this, currentVsyncEnabled, keepRunning]() NO_THREAD_SAFETY_ANALYSIS {
67 return currentVsyncEnabled != mVsyncEnabled || keepRunning != mKeepRunning;
68 });
69 currentVsyncEnabled = mVsyncEnabled;
70 keepRunning = mKeepRunning;
71 }
72 }
73
74 } // namespace impl
75 } // namespace android
76