Merge "Add JNI method to skip epoll_wait if possible" into main (7232f492) · Commits · e / os / android_frameworks_base

core/java/android/os/CombinedMessageQueue/MessageQueue.java

+19 −0

Original line number	Diff line number	Diff line
		@@ -120,6 +120,12 @@ public final class MessageQueue {
		private static boolean sUseConcurrentInitialized = false;
		private static boolean sUseConcurrent;

		/**
		* Determine if the native looper will skip epoll_wait syscalls if nativePollOnce is called with
		* a timeout of 0, which indicates that there are already pending messages.
		*/
		private static boolean sSkipEpollWaitForZeroTimeoutInitialized = false;

		/**
		* Caches process-level checks that determine `sUseConcurrent`.
		* This is to avoid redoing checks that shouldn't change during the process's lifetime.
		@@ -141,6 +147,8 @@ public final class MessageQueue {
		@RavenwoodRedirect
		private native static void nativeSetFileDescriptorEvents(long ptr, int fd, int events);

		private native static void nativeSetSkipEpollWaitForZeroTimeout(long ptr);

		MessageQueue(boolean quitAllowed) {
		getUseConcurrent();
		mQuitAllowed = quitAllowed;
		@@ -148,6 +156,7 @@ public final class MessageQueue {
		mLooperThread = Thread.currentThread();
		mThreadName = mLooperThread.getName();
		mTid = Process.myTid();
		setSkipEpollWaitForZeroTimeout(mPtr);
		}

		static boolean getUseConcurrent() {
		@@ -210,6 +219,16 @@ public final class MessageQueue {
		return false;
		}

		static void setSkipEpollWaitForZeroTimeout(long ptr) {
		if (sSkipEpollWaitForZeroTimeoutInitialized) {
		return;
		}
		if (Flags.nativeLooperSkipEpollWaitForZeroTimeout()) {
		nativeSetSkipEpollWaitForZeroTimeout(ptr);
		}
		sSkipEpollWaitForZeroTimeoutInitialized = true;
		}

		@Override
		protected void finalize() throws Throwable {
		try {

core/java/android/os/flags.aconfig

+7 −0

Original line number	Diff line number	Diff line
		@@ -431,6 +431,13 @@ flag {
		bug: "330345513"
		}

		flag {
		namespace: "system_performance"
		name: "native_looper_skip_epoll_wait_for_zero_timeout"
		description: "Skips epoll_wait if pollOnce is called with a timeout of 0."
		bug: "410218466"
		}

		flag {
		namespace: "system_performance"
		name: "parcel_marshall_bytebuffer"

core/jni/android_os_MessageQueue.cpp

+16 −8

Original line number	Diff line number	Diff line
		@@ -242,6 +242,12 @@ static void android_os_MessageQueue_nativeSetFileDescriptorEvents(JNIEnv* env, j
		nativeMessageQueue->setFileDescriptorEvents(fd, events);
		}

		static void android_os_MessageQueue_nativeSetSkipEpollWaitForZeroTimeout(JNIEnv* env, jclass clazz,
		jlong ptr) {
		NativeMessageQueue* nativeMessageQueue = reinterpret_cast<NativeMessageQueue*>(ptr);
		nativeMessageQueue->getLooper()->setSkipEpollWaitForZeroTimeout();
		}

		// ----------------------------------------------------------------------------

		static const JNINativeMethod gMessageQueueMethods[] = {
		@@ -253,6 +259,8 @@ static const JNINativeMethod gMessageQueueMethods[] = {
		{"nativeIsPolling", "(J)Z", (void*)android_os_MessageQueue_nativeIsPolling},
		{"nativeSetFileDescriptorEvents", "(JII)V",
		(void*)android_os_MessageQueue_nativeSetFileDescriptorEvents},
		{"nativeSetSkipEpollWaitForZeroTimeout", "(J)V",
		(void*)android_os_MessageQueue_nativeSetSkipEpollWaitForZeroTimeout},
		};

		int register_android_os_MessageQueue(JNIEnv* env) {