/*
* Copyright (C) 2007 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 android.os;
import android.util.Log;
import com.android.internal.annotations.GuardedBy;
import com.android.internal.os.BinderInternal;
import com.android.internal.util.StatLogger;
import java.util.HashMap;
import java.util.Map;
/** @hide */
public final class ServiceManager {
private static final String TAG = "ServiceManager";
private static final Object sLock = new Object();
private static IServiceManager sServiceManager;
/**
* Cache for the "well known" services, such as WM and AM.
*/
private static HashMap<String, IBinder> sCache = new HashMap<String, IBinder>();
/**
* We do the "slow log" at most once every this interval.
*/
private static final int SLOW_LOG_INTERVAL_MS = 5000;
/**
* We do the "stats log" at most once every this interval.
*/
private static final int STATS_LOG_INTERVAL_MS = 5000;
/**
* Threshold in uS for a "slow" call, used on core UIDs. We use a more relax value to
* avoid logspam.
*/
private static final long GET_SERVICE_SLOW_THRESHOLD_US_CORE =
SystemProperties.getInt("debug.servicemanager.slow_call_core_ms", 10) * 1000;
/**
* Threshold in uS for a "slow" call, used on non-core UIDs. We use a more relax value to
* avoid logspam.
*/
private static final long GET_SERVICE_SLOW_THRESHOLD_US_NON_CORE =
SystemProperties.getInt("debug.servicemanager.slow_call_ms", 50) * 1000;
/**
* We log stats logging ever this many getService() calls.
*/
private static final int GET_SERVICE_LOG_EVERY_CALLS_CORE =
SystemProperties.getInt("debug.servicemanager.log_calls_core", 100);
/**
* We log stats logging ever this many getService() calls.
*/
private static final int GET_SERVICE_LOG_EVERY_CALLS_NON_CORE =
SystemProperties.getInt("debug.servicemanager.log_calls", 200);
@GuardedBy("sLock")
private static int sGetServiceAccumulatedUs;
@GuardedBy("sLock")
private static int sGetServiceAccumulatedCallCount;
@GuardedBy("sLock")
private static long sLastStatsLogUptime;
@GuardedBy("sLock")
private static long sLastSlowLogUptime;
@GuardedBy("sLock")
private static long sLastSlowLogActualTime;
interface Stats {
int GET_SERVICE = 0;
int COUNT = GET_SERVICE + 1;
}
public static final StatLogger sStatLogger = new StatLogger(new String[] {
"getService()",
});
private static IServiceManager getIServiceManager() {
if (sServiceManager != null) {
return sServiceManager;
}
// Find the service manager
sServiceManager = ServiceManagerNative
.asInterface(Binder.allowBlocking(BinderInternal.getContextObject()));
return sServiceManager;
}
/**
* Returns a reference to a service with the given name.
*
* @param name the name of the service to get
* @return a reference to the service, or <code>null</code> if the service doesn't exist
*/
public static IBinder getService(String name) {
try {
IBinder service = sCache.get(name);
if (service != null) {
return service;
} else {
return Binder.allowBlocking(rawGetService(name));
}
} catch (RemoteException e) {
Log.e(TAG, "error in getService", e);
}
return null;
}
/**
* Returns a reference to a service with the given name, or throws
* {@link NullPointerException} if none is found.
*
* @hide
*/
public static IBinder getServiceOrThrow(String name) throws ServiceNotFoundException {
final IBinder binder = getService(name);
if (binder != null) {
return binder;
} else {
throw new ServiceNotFoundException(name);
}
}
/**
* Place a new @a service called @a name into the service
* manager.
*
* @param name the name of the new service
* @param service the service object
*/
public static void addService(String name, IBinder service) {
addService(name, service, false, IServiceManager.DUMP_FLAG_PRIORITY_DEFAULT);
}
/**
* Place a new @a service called @a name into the service
* manager.
*
* @param name the name of the new service
* @param service the service object
* @param allowIsolated set to true to allow isolated sandboxed processes
* to access this service
*/
public static void addService(String name, IBinder service, boolean allowIsolated) {
addService(name, service, allowIsolated, IServiceManager.DUMP_FLAG_PRIORITY_DEFAULT);
}
/**
* Place a new @a service called @a name into the service
* manager.
*
* @param name the name of the new service
* @param service the service object
* @param allowIsolated set to true to allow isolated sandboxed processes
* @param dumpPriority supported dump priority levels as a bitmask
* to access this service
*/
public static void addService(String name, IBinder service, boolean allowIsolated,
int dumpPriority) {
try {
getIServiceManager().addService(name, service, allowIsolated, dumpPriority);
} catch (RemoteException e) {
Log.e(TAG, "error in addService", e);
}
}
/**
* Retrieve an existing service called @a name from the
* service manager. Non-blocking.
*/
public static IBinder checkService(String name) {
try {
IBinder service = sCache.get(name);
if (service != null) {
return service;
} else {
return Binder.allowBlocking(getIServiceManager().checkService(name));
}
} catch (RemoteException e) {
Log.e(TAG, "error in checkService", e);
return null;
}
}
/**
* Return a list of all currently running services.
* @return an array of all currently running services, or <code>null</code> in
* case of an exception
*/
public static String[] listServices() {
try {
return getIServiceManager().listServices(IServiceManager.DUMP_FLAG_PRIORITY_ALL);
} catch (RemoteException e) {
Log.e(TAG, "error in listServices", e);
return null;
}
}
/**
* This is only intended to be called when the process is first being brought
* up and bound by the activity manager. There is only one thread in the process
* at that time, so no locking is done.
*
* @param cache the cache of service references
* @hide
*/
public static void initServiceCache(Map<String, IBinder> cache) {
if (sCache.size() != 0) {
throw new IllegalStateException("setServiceCache may only be called once");
}
sCache.putAll(cache);
}
/**
* Exception thrown when no service published for given name. This might be
* thrown early during boot before certain services have published
* themselves.
*
* @hide
*/
public static class ServiceNotFoundException extends Exception {
public ServiceNotFoundException(String name) {
super("No service published for: " + name);
}
}
private static IBinder rawGetService(String name) throws RemoteException {
final long start = sStatLogger.getTime();
final IBinder binder = getIServiceManager().getService(name);
final int time = (int) sStatLogger.logDurationStat(Stats.GET_SERVICE, start);
final int myUid = Process.myUid();
final boolean isCore = UserHandle.isCore(myUid);
final long slowThreshold = isCore
? GET_SERVICE_SLOW_THRESHOLD_US_CORE
: GET_SERVICE_SLOW_THRESHOLD_US_NON_CORE;
synchronized (sLock) {
sGetServiceAccumulatedUs += time;
sGetServiceAccumulatedCallCount++;
final long nowUptime = SystemClock.uptimeMillis();
// Was a slow call?
if (time >= slowThreshold) {
// We do a slow log:
// - At most once in every SLOW_LOG_INTERVAL_MS
// - OR it was slower than the previously logged slow call.
if ((nowUptime > (sLastSlowLogUptime + SLOW_LOG_INTERVAL_MS))
|| (sLastSlowLogActualTime < time)) {
EventLogTags.writeServiceManagerSlow(time / 1000, name);
sLastSlowLogUptime = nowUptime;
sLastSlowLogActualTime = time;
}
}
// Every GET_SERVICE_LOG_EVERY_CALLS calls, log the total time spent in getService().
final int logInterval = isCore
? GET_SERVICE_LOG_EVERY_CALLS_CORE
: GET_SERVICE_LOG_EVERY_CALLS_NON_CORE;
if ((sGetServiceAccumulatedCallCount >= logInterval)
&& (nowUptime >= (sLastStatsLogUptime + STATS_LOG_INTERVAL_MS))) {
EventLogTags.writeServiceManagerStats(
sGetServiceAccumulatedCallCount, // Total # of getService() calls.
sGetServiceAccumulatedUs / 1000, // Total time spent in getService() calls.
(int) (nowUptime - sLastStatsLogUptime)); // Uptime duration since last log.
sGetServiceAccumulatedCallCount = 0;
sGetServiceAccumulatedUs = 0;
sLastStatsLogUptime = nowUptime;
}
}
return binder;
}
}