| /* |
| * Copyright (C) 2012 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.os; |
| |
| import android.content.pm.PackageManager; |
| import android.os.Binder; |
| import android.os.IBinder; |
| import android.os.ISchedulingPolicyService; |
| import android.os.Process; |
| import android.os.RemoteException; |
| import android.util.Log; |
| |
| import com.android.server.SystemServerInitThreadPool; |
| |
| /** |
| * The implementation of the scheduling policy service interface. |
| * |
| * @hide |
| */ |
| public class SchedulingPolicyService extends ISchedulingPolicyService.Stub { |
| |
| private static final String TAG = "SchedulingPolicyService"; |
| |
| // Minimum and maximum values allowed for requestPriority parameter prio |
| private static final int PRIORITY_MIN = 1; |
| private static final int PRIORITY_MAX = 3; |
| |
| private static final String[] MEDIA_PROCESS_NAMES = new String[] { |
| "media.swcodec", // /apex/com.android.media.swcodec/bin/mediaswcodec |
| }; |
| private final IBinder.DeathRecipient mDeathRecipient = new IBinder.DeathRecipient() { |
| @Override |
| public void binderDied() { |
| requestCpusetBoost(false /*enable*/, null /*client*/); |
| } |
| }; |
| // Current process that received a cpuset boost |
| private int mBoostedPid = -1; |
| // Current client registered to the death recipient |
| private IBinder mClient; |
| |
| public SchedulingPolicyService() { |
| // system_server (our host) could have crashed before. The app may not survive |
| // it, but mediaserver/media.codec could have, and mediaserver probably tried |
| // to disable the boost while we were dead. |
| // We do a restore of media.codec to default cpuset upon service restart to |
| // catch this case. We can't leave media.codec in boosted state, because we've |
| // lost the death recipient of mClient from mediaserver after the restart, |
| // if mediaserver dies in the future we won't have a notification to reset. |
| // (Note that if mediaserver thinks we're in boosted state before the crash, |
| // the state could go out of sync temporarily until mediaserver enables/disable |
| // boost next time, but this won't be a big issue.) |
| SystemServerInitThreadPool.get().submit(() -> { |
| synchronized (mDeathRecipient) { |
| // only do this if we haven't already got a request to boost. |
| if (mBoostedPid == -1) { |
| int[] nativePids = Process.getPidsForCommands(MEDIA_PROCESS_NAMES); |
| if (nativePids != null && nativePids.length == 1) { |
| mBoostedPid = nativePids[0]; |
| disableCpusetBoost(nativePids[0]); |
| } |
| } |
| } |
| }, TAG + ".<init>"); |
| } |
| |
| // TODO(b/35196900) We should pass the period in time units, rather |
| // than a fixed priority number. |
| public int requestPriority(int pid, int tid, int prio, boolean isForApp) { |
| //Log.i(TAG, "requestPriority(pid=" + pid + ", tid=" + tid + ", prio=" + prio + ")"); |
| |
| // Verify that the caller uid is permitted, priority is in range, |
| // and that the callback thread specified by app belongs to the app that |
| // called mediaserver or audioserver. |
| // Once we've verified that the caller uid is permitted, we can trust the pid but |
| // we can't trust the tid. No need to explicitly check for pid == 0 || tid == 0, |
| // since if not the case then the getThreadGroupLeader() test will also fail. |
| if (!isPermitted() || prio < PRIORITY_MIN || |
| prio > PRIORITY_MAX || Process.getThreadGroupLeader(tid) != pid) { |
| return PackageManager.PERMISSION_DENIED; |
| } |
| if (Binder.getCallingUid() != Process.BLUETOOTH_UID) { |
| try { |
| // make good use of our CAP_SYS_NICE capability |
| Process.setThreadGroup(tid, !isForApp ? |
| Process.THREAD_GROUP_AUDIO_SYS : Process.THREAD_GROUP_RT_APP); |
| } catch (RuntimeException e) { |
| Log.e(TAG, "Failed setThreadGroup: " + e); |
| return PackageManager.PERMISSION_DENIED; |
| } |
| } |
| try { |
| // must be in this order or it fails the schedulability constraint |
| Process.setThreadScheduler(tid, Process.SCHED_FIFO | Process.SCHED_RESET_ON_FORK, |
| prio); |
| } catch (RuntimeException e) { |
| Log.e(TAG, "Failed setThreadScheduler: " + e); |
| return PackageManager.PERMISSION_DENIED; |
| } |
| return PackageManager.PERMISSION_GRANTED; |
| } |
| |
| // Request to move media.codec process between SP_FOREGROUND and SP_TOP_APP. |
| public int requestCpusetBoost(boolean enable, IBinder client) { |
| // Can only allow mediaserver to call this. |
| if (Binder.getCallingPid() != Process.myPid() && |
| Binder.getCallingUid() != Process.MEDIA_UID) { |
| return PackageManager.PERMISSION_DENIED; |
| } |
| |
| int[] nativePids = Process.getPidsForCommands(MEDIA_PROCESS_NAMES); |
| if (nativePids == null || nativePids.length != 1) { |
| Log.e(TAG, "requestCpusetBoost: can't find media.codec process"); |
| return PackageManager.PERMISSION_DENIED; |
| } |
| |
| synchronized (mDeathRecipient) { |
| if (enable) { |
| return enableCpusetBoost(nativePids[0], client); |
| } else { |
| return disableCpusetBoost(nativePids[0]); |
| } |
| } |
| } |
| |
| private int enableCpusetBoost(int pid, IBinder client) { |
| if (mBoostedPid == pid) { |
| return PackageManager.PERMISSION_GRANTED; |
| } |
| |
| // The mediacodec process has changed, clean up the old pid and |
| // client before we boost the new process, so that the state |
| // is left clean if things go wrong. |
| mBoostedPid = -1; |
| if (mClient != null) { |
| try { |
| mClient.unlinkToDeath(mDeathRecipient, 0); |
| } catch (Exception e) { |
| } finally { |
| mClient = null; |
| } |
| } |
| |
| try { |
| client.linkToDeath(mDeathRecipient, 0); |
| |
| Log.i(TAG, "Moving " + pid + " to group " + Process.THREAD_GROUP_TOP_APP); |
| Process.setProcessGroup(pid, Process.THREAD_GROUP_TOP_APP); |
| |
| mBoostedPid = pid; |
| mClient = client; |
| |
| return PackageManager.PERMISSION_GRANTED; |
| } catch (Exception e) { |
| Log.e(TAG, "Failed enableCpusetBoost: " + e); |
| try { |
| // unlink if things go wrong and don't crash. |
| client.unlinkToDeath(mDeathRecipient, 0); |
| } catch (Exception e1) {} |
| } |
| |
| return PackageManager.PERMISSION_DENIED; |
| } |
| |
| private int disableCpusetBoost(int pid) { |
| int boostedPid = mBoostedPid; |
| |
| // Clean up states first. |
| mBoostedPid = -1; |
| if (mClient != null) { |
| try { |
| mClient.unlinkToDeath(mDeathRecipient, 0); |
| } catch (Exception e) { |
| } finally { |
| mClient = null; |
| } |
| } |
| |
| // Try restore the old thread group, no need to fail as the |
| // mediacodec process could be dead just now. |
| if (boostedPid == pid) { |
| try { |
| Log.i(TAG, "Moving " + pid + " back to group default"); |
| Process.setProcessGroup(pid, Process.THREAD_GROUP_DEFAULT); |
| } catch (Exception e) { |
| Log.w(TAG, "Couldn't move pid " + pid + " back to group default"); |
| } |
| } |
| |
| return PackageManager.PERMISSION_GRANTED; |
| } |
| |
| private boolean isPermitted() { |
| // schedulerservice hidl |
| if (Binder.getCallingPid() == Process.myPid()) { |
| return true; |
| } |
| |
| switch (Binder.getCallingUid()) { |
| case Process.AUDIOSERVER_UID: // fastcapture, fastmixer |
| case Process.CAMERASERVER_UID: // camera high frame rate recording |
| case Process.BLUETOOTH_UID: // Bluetooth audio playback |
| return true; |
| default: |
| return false; |
| } |
| } |
| } |