1 /*
2  * Copyright (C) 2019 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 "android_graphics_HardwareRendererObserver.h"
18 
19 #include "graphics_jni_helpers.h"
20 #include "nativehelper/jni_macros.h"
21 
22 #include <array>
23 
24 namespace android {
25 
26 struct {
27     jclass clazz;
28     jmethodID callback;
29 } gHardwareRendererObserverClassInfo;
30 
getenv(JavaVM * vm)31 static JNIEnv* getenv(JavaVM* vm) {
32     JNIEnv* env;
33     if (vm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_6) != JNI_OK) {
34         LOG_ALWAYS_FATAL("Failed to get JNIEnv for JavaVM: %p", vm);
35     }
36     return env;
37 }
38 
HardwareRendererObserver(JavaVM * vm,jobject observer,bool waitForPresentTime)39 HardwareRendererObserver::HardwareRendererObserver(JavaVM* vm, jobject observer,
40                                                    bool waitForPresentTime)
41         : uirenderer::FrameMetricsObserver(waitForPresentTime), mVm(vm) {
42     mObserver = getenv(mVm)->NewGlobalRef(observer);
43     LOG_ALWAYS_FATAL_IF(mObserver == nullptr, "unable to create frame stats observer reference");
44 }
45 
~HardwareRendererObserver()46 HardwareRendererObserver::~HardwareRendererObserver() {
47     JNIEnv* env = getenv(mVm);
48     env->DeleteGlobalRef(mObserver);
49 }
50 
getNextBuffer(JNIEnv * env,jlongArray metrics,int * dropCount)51 bool HardwareRendererObserver::getNextBuffer(JNIEnv* env, jlongArray metrics, int* dropCount) {
52     jsize bufferSize = env->GetArrayLength(reinterpret_cast<jarray>(metrics));
53     LOG_ALWAYS_FATAL_IF(bufferSize != HardwareRendererObserver::kBufferSize,
54                         "Mismatched Java/Native FrameMetrics data format.");
55 
56     FrameMetricsNotification& elem = mRingBuffer[mNextInQueue];
57     if (elem.hasData.load()) {
58         env->SetLongArrayRegion(metrics, 0, kBufferSize, elem.buffer);
59         *dropCount = elem.dropCount;
60         mNextInQueue = (mNextInQueue + 1) % kRingSize;
61         elem.hasData = false;
62         return true;
63     }
64 
65     return false;
66 }
67 
notify(const int64_t * stats)68 void HardwareRendererObserver::notify(const int64_t* stats) {
69     if (!mKeepListening) return;
70 
71     FrameMetricsNotification& elem = mRingBuffer[mNextFree];
72 
73     if (!elem.hasData.load()) {
74         memcpy(elem.buffer, stats, kBufferSize * sizeof(stats[0]));
75 
76         elem.dropCount = mDroppedReports;
77         mDroppedReports = 0;
78         mNextFree = (mNextFree + 1) % kRingSize;
79         elem.hasData = true;
80 
81         JNIEnv* env = getenv(mVm);
82         mKeepListening = env->CallStaticBooleanMethod(gHardwareRendererObserverClassInfo.clazz,
83                                                       gHardwareRendererObserverClassInfo.callback,
84                                                       mObserver);
85     } else {
86         mDroppedReports++;
87     }
88 }
89 
android_graphics_HardwareRendererObserver_createObserver(JNIEnv * env,jobject,jobject weakRefThis,jboolean waitForPresentTime)90 static jlong android_graphics_HardwareRendererObserver_createObserver(JNIEnv* env,
91                                                                       jobject /*clazz*/,
92                                                                       jobject weakRefThis,
93                                                                       jboolean waitForPresentTime) {
94     JavaVM* vm = nullptr;
95     if (env->GetJavaVM(&vm) != JNI_OK) {
96         LOG_ALWAYS_FATAL("Unable to get Java VM");
97         return 0;
98     }
99 
100     HardwareRendererObserver* observer =
101             new HardwareRendererObserver(vm, weakRefThis, waitForPresentTime);
102     return reinterpret_cast<jlong>(observer);
103 }
104 
android_graphics_HardwareRendererObserver_getNextBuffer(JNIEnv * env,jobject,jlong observerPtr,jlongArray metrics)105 static jint android_graphics_HardwareRendererObserver_getNextBuffer(JNIEnv* env, jobject,
106                                                                     jlong observerPtr,
107                                                                     jlongArray metrics) {
108     HardwareRendererObserver* observer = reinterpret_cast<HardwareRendererObserver*>(observerPtr);
109     int dropCount = 0;
110     if (observer->getNextBuffer(env, metrics, &dropCount)) {
111         return dropCount;
112     } else {
113         return -1;
114     }
115 }
116 
117 static const std::array gMethods = {
118         MAKE_JNI_NATIVE_METHOD("nCreateObserver", "(Ljava/lang/ref/WeakReference;Z)J",
119                                android_graphics_HardwareRendererObserver_createObserver),
120         MAKE_JNI_NATIVE_METHOD("nGetNextBuffer", "(J[J)I",
121                                android_graphics_HardwareRendererObserver_getNextBuffer),
122 };
123 
register_android_graphics_HardwareRendererObserver(JNIEnv * env)124 int register_android_graphics_HardwareRendererObserver(JNIEnv* env) {
125 
126     jclass observerClass = FindClassOrDie(env, "android/graphics/HardwareRendererObserver");
127     gHardwareRendererObserverClassInfo.clazz =
128             reinterpret_cast<jclass>(env->NewGlobalRef(observerClass));
129     gHardwareRendererObserverClassInfo.callback = GetStaticMethodIDOrDie(
130             env, observerClass, "invokeDataAvailable", "(Ljava/lang/ref/WeakReference;)Z");
131 
132     return RegisterMethodsOrDie(env, "android/graphics/HardwareRendererObserver",
133                                 gMethods.data(), gMethods.size());
134 
135 }
136 
137 } // namespace android