diff options
| -rw-r--r-- | core/java/android/net/IpReachabilityMonitor.java | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/core/java/android/net/IpReachabilityMonitor.java b/core/java/android/net/IpReachabilityMonitor.java index 88fb014..2283004 100644 --- a/core/java/android/net/IpReachabilityMonitor.java +++ b/core/java/android/net/IpReachabilityMonitor.java @@ -18,6 +18,7 @@ package android.net; import com.android.internal.annotations.GuardedBy; +import android.content.Context; import android.net.LinkAddress; import android.net.LinkProperties; import android.net.LinkProperties.ProvisioningChange; @@ -31,6 +32,7 @@ import android.net.netlink.RtNetlinkNeighborMessage; import android.net.netlink.StructNdaCacheInfo; import android.net.netlink.StructNdMsg; import android.net.netlink.StructNlMsgHdr; +import android.os.PowerManager; import android.os.SystemClock; import android.system.ErrnoException; import android.system.NetlinkSocketAddress; @@ -74,6 +76,7 @@ public class IpReachabilityMonitor { } private final Object mLock = new Object(); + private final PowerManager.WakeLock mWakeLock; private final String mInterfaceName; private final int mInterfaceIndex; private final Callback mCallback; @@ -136,7 +139,8 @@ public class IpReachabilityMonitor { return returnValue; } - public IpReachabilityMonitor(String ifName, Callback callback) throws IllegalArgumentException { + public IpReachabilityMonitor(Context context, String ifName, Callback callback) + throws IllegalArgumentException { mInterfaceName = ifName; int ifIndex = -1; try { @@ -145,6 +149,8 @@ public class IpReachabilityMonitor { } catch (SocketException | NullPointerException e) { throw new IllegalArgumentException("invalid interface '" + ifName + "': ", e); } + mWakeLock = ((PowerManager) context.getSystemService(Context.POWER_SERVICE)).newWakeLock( + PowerManager.PARTIAL_WAKE_LOCK, TAG + "." + mInterfaceName); mCallback = callback; mNetlinkSocketObserver = new NetlinkSocketObserver(); mObserverThread = new Thread(mNetlinkSocketObserver); @@ -291,6 +297,17 @@ public class IpReachabilityMonitor { synchronized (mLock) { ipProbeList.addAll(mIpWatchList.keySet()); } + + if (!ipProbeList.isEmpty() && stillRunning()) { + // Keep the CPU awake long enough to allow all ARP/ND + // probes a reasonable chance at success. See b/23197666. + // + // The wakelock we use is (by default) refcounted, and this version + // of acquire(timeout) queues a release message to keep acquisitions + // and releases balanced. + mWakeLock.acquire(getProbeWakeLockDuration()); + } + for (InetAddress target : ipProbeList) { if (!stillRunning()) { break; @@ -299,6 +316,22 @@ public class IpReachabilityMonitor { } } + private long getProbeWakeLockDuration() { + // Ideally, this would be computed by examining the values of: + // + // /proc/sys/net/ipv[46]/neigh/<ifname>/ucast_solicit + // + // and: + // + // /proc/sys/net/ipv[46]/neigh/<ifname>/retrans_time_ms + // + // For now, just make some assumptions. + final long numUnicastProbes = 3; + final long retransTimeMs = 1000; + final long gracePeriodMs = 500; + return (numUnicastProbes * retransTimeMs) + gracePeriodMs; + } + // TODO: simply the number of objects by making this extend Thread. private final class NetlinkSocketObserver implements Runnable { |