Add CameraService Watchdog
This CL adds a watchdog used to detect issues in cameraservice/
Camera HAL. It uses a timer that can be customized to monitor calls
and kills the process if a fixed amount of time has elapsed without
a successful execution of the monitored call.
The following cases are included in this CL: flush(), close().
Further cases can be added with the APIs in watchdog.
Test: Manual; Tested by force triggering watchdog with custom timer
values and while(true) or sleep in monitored calls
Bug: 62296107
Change-Id: Ia7b4a3fd9395210800a391c62b4ea757efbb3b00
diff --git a/services/camera/libcameraservice/CameraServiceWatchdog.cpp b/services/camera/libcameraservice/CameraServiceWatchdog.cpp
new file mode 100644
index 0000000..fcd6ebe
--- /dev/null
+++ b/services/camera/libcameraservice/CameraServiceWatchdog.cpp
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2022 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.
+ */
+
+#define LOG_TAG "CameraServiceWatchdog"
+
+#include "CameraServiceWatchdog.h"
+
+namespace android {
+
+bool CameraServiceWatchdog::threadLoop()
+{
+ {
+ AutoMutex _l(mWatchdogLock);
+
+ while (mPause) {
+ mWatchdogCondition.wait(mWatchdogLock);
+ }
+ }
+
+ std::this_thread::sleep_for(std::chrono::milliseconds(mCycleLengthMs));
+
+ {
+ AutoMutex _l(mWatchdogLock);
+
+ for (auto it = tidToCycleCounterMap.begin(); it != tidToCycleCounterMap.end(); it++) {
+ uint32_t currentThreadId = it->first;
+
+ tidToCycleCounterMap[currentThreadId]++;
+
+ if (tidToCycleCounterMap[currentThreadId] >= mMaxCycles) {
+ ALOGW("CameraServiceWatchdog triggering kill for pid: %d", getpid());
+ kill(getpid(), SIGKILL);
+ }
+ }
+ }
+
+ return true;
+}
+
+void CameraServiceWatchdog::requestExit()
+{
+ Thread::requestExit();
+
+ AutoMutex _l(mWatchdogLock);
+
+ tidToCycleCounterMap.clear();
+
+ if (mPause) {
+ mPause = false;
+ mWatchdogCondition.signal();
+ }
+}
+
+void CameraServiceWatchdog::stop(uint32_t tid)
+{
+ AutoMutex _l(mWatchdogLock);
+
+ tidToCycleCounterMap.erase(tid);
+
+ if (tidToCycleCounterMap.empty()) {
+ mPause = true;
+ }
+}
+
+void CameraServiceWatchdog::start(uint32_t tid)
+{
+ AutoMutex _l(mWatchdogLock);
+
+ tidToCycleCounterMap[tid] = 0;
+
+ if (mPause) {
+ mPause = false;
+ mWatchdogCondition.signal();
+ }
+}
+
+} // namespace android