Boost thread priority when holding the WM lock (b72e651f) · Commits · e / os / android_frameworks_base

services/core/Android.mk

+3 −3

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		@@ -39,8 +39,8 @@ endif

		LOCAL_JACK_FLAGS := \
		-D jack.transformations.boost-locked-region-priority=true \
		-D jack.transformations.boost-locked-region-priority.classname=com.android.server.am.ActivityManagerService \
		-D jack.transformations.boost-locked-region-priority.request=com.android.server.am.ActivityManagerService\#boostPriorityForLockedSection \
		-D jack.transformations.boost-locked-region-priority.reset=com.android.server.am.ActivityManagerService\#resetPriorityAfterLockedSection
		-D jack.transformations.boost-locked-region-priority.classname=com.android.server.am.ActivityManagerService,com.android.server.wm.WindowHashMap \
		-D jack.transformations.boost-locked-region-priority.request=com.android.server.am.ActivityManagerService\#boostPriorityForLockedSection,com.android.server.wm.WindowManagerService\#boostPriorityForLockedSection \
		-D jack.transformations.boost-locked-region-priority.reset=com.android.server.am.ActivityManagerService\#resetPriorityAfterLockedSection,com.android.server.wm.WindowManagerService\#resetPriorityAfterLockedSection

		include $(BUILD_STATIC_JAVA_LIBRARY)

services/core/java/com/android/server/ThreadPriorityBooster.java

0 → 100644

+76 −0

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		/*
		* Copyright (C) 2017 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
		*/

		package com.android.server;

		import android.os.Process;

		/**
		* Utility class to boost threads in sections where important locks are held.
		*/
		public class ThreadPriorityBooster {

		private final int mBoostToPriority;
		private final int mLockGuardIndex;

		private final ThreadLocal<PriorityState> mThreadState = new ThreadLocal<PriorityState>() {
		@Override protected PriorityState initialValue() {
		return new PriorityState();
		}
		};

		public ThreadPriorityBooster(int boostToPriority, int lockGuardIndex) {
		mBoostToPriority = boostToPriority;
		mLockGuardIndex = lockGuardIndex;
		}

		public void boost() {
		final int tid = Process.myTid();
		final int prevPriority = Process.getThreadPriority(tid);
		PriorityState state = mThreadState.get();
		if (state.regionCounter == 0 && prevPriority > mBoostToPriority) {
		state.prevPriority = prevPriority;
		Process.setThreadPriority(tid, mBoostToPriority);
		}
		state.regionCounter++;
		if (LockGuard.ENABLED) {
		LockGuard.guard(mLockGuardIndex);
		}
		}

		public void reset() {
		PriorityState state = mThreadState.get();
		state.regionCounter--;
		if (state.regionCounter == 0 && state.prevPriority > mBoostToPriority) {
		Process.setThreadPriority(Process.myTid(), state.prevPriority);
		}
		}

		private static class PriorityState {

		/**
		* Acts as counter for number of synchronized region that needs to acquire 'this' as a lock
		* the current thread is currently in. When it drops down to zero, we will no longer boost
		* the thread's priority.
		*/
		int regionCounter;

		/**
		* The thread's previous priority before boosting.
		*/
		int prevPriority;
		}
		}
		No newline at end of file

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

+158 −149

File changed.

Preview size limit exceeded, changes collapsed.

services/core/java/com/android/server/wm/WindowContainerController.java

+1 −1

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		@@ -33,7 +33,7 @@ class WindowContainerController<E extends WindowContainer, I extends WindowConta

		final WindowManagerService mService;
		final RootWindowContainer mRoot;
		final HashMap<IBinder, WindowState> mWindowMap;
		final WindowHashMap mWindowMap;

		// The window container this controller owns.
		E mContainer;

services/core/java/com/android/server/wm/WindowHashMap.java

0 → 100644

+28 −0

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		/*
		* Copyright (C) 2017 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
		*/

		package com.android.server.wm;

		import android.os.IBinder;

		import java.util.HashMap;

		/**
		* Subclass of HashMap such that we can instruct the compiler to boost our thread priority when
		* locking this class. See makefile.
		*/
		class WindowHashMap extends HashMap<IBinder, WindowState> {
		}