am 160edb36: Add ability to guard a thread against setting its own prio to bg (d3233ae9) · Commits · e / os / android_frameworks_base

core/java/android/os/Process.java

+9 −0

Original line number	Original line	Diff line number	Diff line
	@@ -625,6 +625,15 @@ public class Process {
	public static final native void setThreadPriority(int tid, int priority)		public static final native void setThreadPriority(int tid, int priority)
	throws IllegalArgumentException, SecurityException;		throws IllegalArgumentException, SecurityException;

			/**
			* Call with 'false' to cause future calls to {@link #setThreadPriority(int)} to
			* throw an exception if passed a background-level thread priority. This is only
			* effective if the JNI layer is built with GUARD_THREAD_PRIORITY defined to 1.
			*
			* @hide
			*/
			public static final native void setCanSelfBackground(boolean backgroundOk);

	/**		/**
	* Sets the scheduling group for a thread.		* Sets the scheduling group for a thread.
	* @hide		* @hide

core/jni/android_util_Process.cpp

+39 −0

Original line number	Original line	Diff line number	Diff line
	@@ -52,9 +52,15 @@ pid_t gettid() { return syscall(__NR_gettid);}
	#endif		#endif

	#define POLICY_DEBUG 0		#define POLICY_DEBUG 0
			#define GUARD_THREAD_PRIORITY 0

	using namespace android;		using namespace android;

			#if GUARD_THREAD_PRIORITY
			Mutex gKeyCreateMutex;
			static pthread_key_t gBgKey = -1;
			#endif

	static void signalExceptionForPriorityError(JNIEnv* env, jobject obj, int err)		static void signalExceptionForPriorityError(JNIEnv* env, jobject obj, int err)
	{		{
	switch (err) {		switch (err) {
	@@ -264,9 +270,41 @@ void android_os_Process_setProcessGroup(JNIEnv* env, jobject clazz, int pid, jin
	closedir(d);		closedir(d);
	}		}

			static void android_os_Process_setCanSelfBackground(JNIEnv* env, jobject clazz, jboolean bgOk) {
			// Establishes the calling thread as illegal to put into the background.
			// Typically used only for the system process's main looper.
			#if GUARD_THREAD_PRIORITY
			LOGV("Process.setCanSelfBackground(%d) : tid=%d", bgOk, androidGetTid());
			{
			Mutex::Autolock _l(gKeyCreateMutex);
			if (gBgKey == -1) {
			pthread_key_create(&gBgKey, NULL);
			}
			}

			// inverted: not-okay, we set a sentinel value
			pthread_setspecific(gBgKey, (void*)(bgOk ? 0 : 0xbaad));
			#endif
			}

	void android_os_Process_setThreadPriority(JNIEnv* env, jobject clazz,		void android_os_Process_setThreadPriority(JNIEnv* env, jobject clazz,
	jint pid, jint pri)		jint pid, jint pri)
	{		{
			#if GUARD_THREAD_PRIORITY
			// if we're putting the current thread into the background, check the TLS
			// to make sure this thread isn't guarded. If it is, raise an exception.
			if (pri >= ANDROID_PRIORITY_BACKGROUND) {
			if (pid == androidGetTid()) {
			void* bgOk = pthread_getspecific(gBgKey);
			if (bgOk == ((void*)0xbaad)) {
			LOGE("Thread marked fg-only put self in background!");
			jniThrowException(env, "java/lang/SecurityException", "May not put this thread into background");
			return;
			}
			}
			}
			#endif

	int rc = androidSetThreadPriority(pid, pri);		int rc = androidSetThreadPriority(pid, pri);
	if (rc != 0) {		if (rc != 0) {
	if (rc == INVALID_OPERATION) {		if (rc == INVALID_OPERATION) {
	@@ -852,6 +890,7 @@ static const JNINativeMethod methods[] = {
	{"getUidForName", "(Ljava/lang/String;)I", (void*)android_os_Process_getUidForName},		{"getUidForName", "(Ljava/lang/String;)I", (void*)android_os_Process_getUidForName},
	{"getGidForName", "(Ljava/lang/String;)I", (void*)android_os_Process_getGidForName},		{"getGidForName", "(Ljava/lang/String;)I", (void*)android_os_Process_getGidForName},
	{"setThreadPriority", "(II)V", (void*)android_os_Process_setThreadPriority},		{"setThreadPriority", "(II)V", (void*)android_os_Process_setThreadPriority},
			{"setCanSelfBackground", "(Z)V", (void*)android_os_Process_setCanSelfBackground},
	{"setThreadPriority", "(I)V", (void*)android_os_Process_setCallingThreadPriority},		{"setThreadPriority", "(I)V", (void*)android_os_Process_setCallingThreadPriority},
	{"getThreadPriority", "(I)I", (void*)android_os_Process_getThreadPriority},		{"getThreadPriority", "(I)I", (void*)android_os_Process_getThreadPriority},
	{"setThreadGroup", "(II)V", (void*)android_os_Process_setThreadGroup},		{"setThreadGroup", "(II)V", (void*)android_os_Process_setThreadGroup},

services/java/com/android/server/SystemServer.java

+2 −1

Original line number	Original line	Diff line number	Diff line
	@@ -80,6 +80,7 @@ class ServerThread extends Thread {
	android.os.Process.THREAD_PRIORITY_FOREGROUND);		android.os.Process.THREAD_PRIORITY_FOREGROUND);

	BinderInternal.disableBackgroundScheduling(true);		BinderInternal.disableBackgroundScheduling(true);
			android.os.Process.setCanSelfBackground(false);

	String factoryTestStr = SystemProperties.get("ro.factorytest");		String factoryTestStr = SystemProperties.get("ro.factorytest");
	int factoryTest = "".equals(factoryTestStr) ? SystemServer.FACTORY_TEST_OFF		int factoryTest = "".equals(factoryTestStr) ? SystemServer.FACTORY_TEST_OFF

services/java/com/android/server/WindowManagerService.java

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -572,6 +572,7 @@ public class WindowManagerService extends IWindowManager.Stub
	mHaveInputMethods);		mHaveInputMethods);
	android.os.Process.setThreadPriority(		android.os.Process.setThreadPriority(
	android.os.Process.THREAD_PRIORITY_DISPLAY);		android.os.Process.THREAD_PRIORITY_DISPLAY);
			android.os.Process.setCanSelfBackground(false);

	synchronized (this) {		synchronized (this) {
	mService = s;		mService = s;
	@@ -607,6 +608,7 @@ public class WindowManagerService extends IWindowManager.Stub
	// Log.VERBOSE, "WindowManagerPolicy", Log.LOG_ID_SYSTEM));		// Log.VERBOSE, "WindowManagerPolicy", Log.LOG_ID_SYSTEM));
	android.os.Process.setThreadPriority(		android.os.Process.setThreadPriority(
	android.os.Process.THREAD_PRIORITY_FOREGROUND);		android.os.Process.THREAD_PRIORITY_FOREGROUND);
			android.os.Process.setCanSelfBackground(false);
	mPolicy.init(mContext, mService, mPM);		mPolicy.init(mContext, mService, mPM);

	synchronized (this) {		synchronized (this) {

services/java/com/android/server/am/ActivityManagerService.java

+1 −0

Original line number	Original line	Diff line number	Diff line
	@@ -1259,6 +1259,7 @@ public final class ActivityManagerService extends ActivityManagerNative implemen

	android.os.Process.setThreadPriority(		android.os.Process.setThreadPriority(
	android.os.Process.THREAD_PRIORITY_FOREGROUND);		android.os.Process.THREAD_PRIORITY_FOREGROUND);
			android.os.Process.setCanSelfBackground(false);

	ActivityManagerService m = new ActivityManagerService();		ActivityManagerService m = new ActivityManagerService();