Add "call" method on ContentProvider.

This permits implementing interfaces which are faster than using
remote Cursors.  It then uses it for Settings & SettingProvider, which
together account for ~50% of total ContentProvider event loop stalls
across Froyo dogfooders.

For fetching Settings this looks like it should reduce average
Settings lookup from 10 ms to 0.4 ms on Sholes, once the
SettingsProvider serves most gets from in-memory cache.  Currently it
brings the Sholes average down from 10ms to 2.5 ms while still using
SQLite queries on each get.

1 files changed, 33 insertions, 1 deletions

diff --git a/core/java/android/content/ContentProviderNative.java b/core/java/android/content/ContentProviderNative.java
index bacb6849e11f..81b805564921 100644
--- a/core/java/android/content/ContentProviderNative.java
+++ b/core/java/android/content/ContentProviderNative.java
@@ -26,6 +26,7 @@ import android.database.IBulkCursor;
 import android.database.IContentObserver;
 import android.net.Uri;
 import android.os.Binder;
+import android.os.Bundle;
 import android.os.RemoteException;
 import android.os.IBinder;
 import android.os.Parcel;
@@ -222,6 +223,21 @@ abstract public class ContentProviderNative extends Binder implements IContentPr
                     }
                     return true;
                 }
+
+                case CALL_TRANSACTION:
+                {
+                    data.enforceInterface(IContentProvider.descriptor);
+
+                    String method = data.readString();
+                    String stringArg = data.readString();
+                    Bundle args = data.readBundle();
+
+                    Bundle responseBundle = call(method, stringArg, args);
+
+                    reply.writeNoException();
+                    reply.writeBundle(responseBundle);
+                    return true;
+                }
             }
         } catch (Exception e) {
             DatabaseUtils.writeExceptionToParcel(reply, e);
@@ -485,6 +501,22 @@ final class ContentProviderProxy implements IContentProvider
         return fd;
     }
 
+    public Bundle call(String method, String request, Bundle args)
+            throws RemoteException {
+        Parcel data = Parcel.obtain();
+        Parcel reply = Parcel.obtain();
+
+        data.writeInterfaceToken(IContentProvider.descriptor);
+
+        data.writeString(method);
+        data.writeString(request);
+        data.writeBundle(args);
+
+        mRemote.transact(IContentProvider.CALL_TRANSACTION, data, reply, 0);
+
+        DatabaseUtils.readExceptionFromParcel(reply);
+        return reply.readBundle();
+    }
+
     private IBinder mRemote;
 }
-