audio services: monitor execution time for binder commands

Add a mechanism to monitor execution time of incoming binder
calls to audio flinger and audio policy and cause native audioserver
restart in case of timeout.

Bug: 69250055
Test: manual. audio smoke tests
Change-Id: I01b5bf2599fb2a4cd265cbbe8d4e34b2b059aaf4

include/media/TimeCheck.h

@@ -0,0 +1 @@
+../../media/libmedia/include/media/TimeCheck.h

media/libaudioclient/IAudioFlinger.cpp

@@ -24,6 +24,7 @@
 
 #include <binder/IPCThreadState.h>
 #include <binder/Parcel.h>
+#include <media/TimeCheck.h>
 #include <private/android_filesystem_config.h>
 
 #include "IAudioFlinger.h"
@@ -933,6 +934,8 @@ status_t BnAudioFlinger::onTransact(
             break;
     }
 
+    TimeCheck check("IAudioFlinger");
+
     switch (code) {
         case CREATE_TRACK: {
             CHECK_INTERFACE(IAudioFlinger, data, reply);

media/libaudioclient/IAudioPolicyService.cpp

@@ -27,6 +27,7 @@
 
 #include <media/AudioEffect.h>
 #include <media/IAudioPolicyService.h>
+#include <media/TimeCheck.h>
 #include <private/android_filesystem_config.h>
 #include <system/audio.h>
 
@@ -882,6 +883,8 @@ status_t BnAudioPolicyService::onTransact(
             break;
     }
 
+    TimeCheck check("IAudioPolicyService");
+
     switch (code) {
         case SET_DEVICE_CONNECTION_STATE: {
             CHECK_INTERFACE(IAudioPolicyService, data, reply);

media/libmedia/Android.bp

@@ -18,7 +18,7 @@ cc_library {
     vndk: {
         enabled: true,
     },
-    srcs: ["AudioParameter.cpp", "TypeConverter.cpp"],
+    srcs: ["AudioParameter.cpp", "TypeConverter.cpp", "TimeCheck.cpp"],
     cflags: [
         "-Werror",
         "-Wno-error=deprecated-declarations",

media/libmedia/TimeCheck.cpp

@@ -0,0 +1,88 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+
+#include <media/TimeCheck.h>
+
+namespace android {
+
+/* static */
+sp<TimeCheck::TimeCheckThread> TimeCheck::getTimeCheckThread()
+{
+    static sp<TimeCheck::TimeCheckThread> sTimeCheckThread = new TimeCheck::TimeCheckThread();
+    return sTimeCheckThread;
+}
+
+TimeCheck::TimeCheck(const char *tag, uint32_t timeoutMs)
+    : mEndTimeNs(getTimeCheckThread()->startMonitoring(tag, timeoutMs))
+{
+}
+
+TimeCheck::~TimeCheck() {
+    getTimeCheckThread()->stopMonitoring(mEndTimeNs);
+}
+
+TimeCheck::TimeCheckThread::~TimeCheckThread()
+{
+    AutoMutex _l(mMutex);
+    requestExit();
+    mMonitorRequests.clear();
+    mCond.signal();
+}
+
+nsecs_t TimeCheck::TimeCheckThread::startMonitoring(const char *tag, uint32_t timeoutMs) {
+    Mutex::Autolock _l(mMutex);
+    nsecs_t endTimeNs = systemTime() + milliseconds(timeoutMs);
+    for (; mMonitorRequests.indexOfKey(endTimeNs) >= 0; ++endTimeNs);
+    mMonitorRequests.add(endTimeNs, tag);
+    mCond.signal();
+    return endTimeNs;
+}
+
+void TimeCheck::TimeCheckThread::stopMonitoring(nsecs_t endTimeNs) {
+    Mutex::Autolock _l(mMutex);
+    mMonitorRequests.removeItem(endTimeNs);
+    mCond.signal();
+}
+
+bool TimeCheck::TimeCheckThread::threadLoop()
+{
+    status_t status = TIMED_OUT;
+    const char *tag;
+    {
+        AutoMutex _l(mMutex);
+
+        if (exitPending()) {
+            return false;
+        }
+
+        nsecs_t endTimeNs = INT64_MAX;
+        // KeyedVector mMonitorRequests is ordered so take first entry as next timeout
+        if (mMonitorRequests.size() != 0) {
+            endTimeNs = mMonitorRequests.keyAt(0);
+            tag = mMonitorRequests.valueAt(0);
+        }
+
+        const nsecs_t waitTimeNs = endTimeNs - systemTime();
+        if (waitTimeNs > 0) {
+            status = mCond.waitRelative(mMutex, waitTimeNs);
+        }
+    }
+    LOG_ALWAYS_FATAL_IF(status != NO_ERROR, "TimeCheck timeout for %s", tag);
+    return true;
+}
+
+}; // namespace android

media/libmedia/include/media/TimeCheck.h

@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2018 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.
+ */
+
+
+#ifndef ANDROID_TIME_CHECK_H
+#define ANDROID_TIME_CHECK_H
+
+#include <utils/KeyedVector.h>
+#include <utils/Thread.h>
+
+
+namespace android {
+
+// A class monitoring execution time for a code block (scoped variable) and causing an assert
+// if it exceeds a certain time
+
+class TimeCheck {
+public:
+
+    // The default timeout is chosen to be less than system server watchdog timeout
+    static constexpr uint32_t kDefaultTimeOutMs = 5000;
+
+            TimeCheck(const char *tag, uint32_t timeoutMs = kDefaultTimeOutMs);
+            ~TimeCheck();
+
+private:
+
+    class TimeCheckThread : public Thread {
+    public:
+
+                            TimeCheckThread() {}
+        virtual             ~TimeCheckThread() override;
+
+                nsecs_t     startMonitoring(const char *tag, uint32_t timeoutMs);
+                void        stopMonitoring(nsecs_t endTimeNs);
+
+    private:
+
+                // RefBase
+        virtual void        onFirstRef() override { run("TimeCheckThread", PRIORITY_URGENT_AUDIO); }
+
+                // Thread
+        virtual bool        threadLoop() override;
+
+                Condition           mCond;
+                Mutex               mMutex;
+                // using the end time in ns as key is OK given the risk is low that two entries
+                // are added in such a way that <add time> + <timeout> are the same for both.
+                KeyedVector< nsecs_t, const char*>  mMonitorRequests;
+    };
+
+    static sp<TimeCheckThread> getTimeCheckThread();
+
+    const           nsecs_t mEndTimeNs;
+};
+
+}; // namespace android
+
+#endif  // ANDROID_TIME_CHECK_H