1 files changed, 82 insertions, 0 deletions
diff --git a/services/surfaceflinger/Scheduler/EventControlThread.cpp b/services/surfaceflinger/Scheduler/EventControlThread.cpp
new file mode 100644
index 0000000000..7f9db9ca2d
--- /dev/null
+++ b/services/surfaceflinger/Scheduler/EventControlThread.cpp
@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// TODO(b/129481165): remove the #pragma below and fix conversion issues
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wconversion"
+
+#include <pthread.h>
+#include <sched.h>
+#include <sys/resource.h>
+
+#include <cutils/sched_policy.h>
+#include <log/log.h>
+#include <system/thread_defs.h>
+
+#include "EventControlThread.h"
+
+namespace android {
+
+EventControlThread::~EventControlThread() = default;
+
+namespace impl {
+
+EventControlThread::EventControlThread(EventControlThread::SetVSyncEnabledFunction function)
+      : mSetVSyncEnabled(std::move(function)) {
+    pthread_setname_np(mThread.native_handle(), "EventControlThread");
+
+    pid_t tid = pthread_gettid_np(mThread.native_handle());
+    setpriority(PRIO_PROCESS, tid, ANDROID_PRIORITY_URGENT_DISPLAY);
+    set_sched_policy(tid, SP_FOREGROUND);
+}
+
+EventControlThread::~EventControlThread() {
+    {
+        std::lock_guard<std::mutex> lock(mMutex);
+        mKeepRunning = false;
+        mCondition.notify_all();
+    }
+    mThread.join();
+}
+
+void EventControlThread::setVsyncEnabled(bool enabled) {
+    std::lock_guard<std::mutex> lock(mMutex);
+    mVsyncEnabled = enabled;
+    mCondition.notify_all();
+}
+
+// Unfortunately std::unique_lock gives warnings with -Wthread-safety
+void EventControlThread::threadMain() NO_THREAD_SAFETY_ANALYSIS {
+    auto keepRunning = true;
+    auto currentVsyncEnabled = false;
+
+    while (keepRunning) {
+        mSetVSyncEnabled(currentVsyncEnabled);
+
+        std::unique_lock<std::mutex> lock(mMutex);
+        mCondition.wait(lock, [this, currentVsyncEnabled, keepRunning]() NO_THREAD_SAFETY_ANALYSIS {
+            return currentVsyncEnabled != mVsyncEnabled || keepRunning != mKeepRunning;
+        });
+        currentVsyncEnabled = mVsyncEnabled;
+        keepRunning = mKeepRunning;
+    }
+}
+
+} // namespace impl
+} // namespace android
+
+// TODO(b/129481165): remove the #pragma below and fix conversion issues
+#pragma clang diagnostic pop // ignored "-Wconversion"