Use scheduling policy service

Change-Id: I3c09da1dc0de5039d0c15ce7fb2bc373fa398712
diff --git a/services/audioflinger/SchedulingPolicyService.cpp b/services/audioflinger/SchedulingPolicyService.cpp
new file mode 100644
index 0000000..59cc99a
--- /dev/null
+++ b/services/audioflinger/SchedulingPolicyService.cpp
@@ -0,0 +1,52 @@
+/*
+ * 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.
+ */
+
+#include <binder/IServiceManager.h>
+#include <utils/Mutex.h>
+#include "ISchedulingPolicyService.h"
+#include "SchedulingPolicyService.h"
+
+namespace android {
+
+static sp<ISchedulingPolicyService> sSchedulingPolicyService;
+static const String16 _scheduling_policy("scheduling_policy");
+static Mutex sMutex;
+
+int requestPriority(pid_t pid, pid_t tid, int32_t prio)
+{
+    // FIXME merge duplicated code related to service lookup, caching, and error recovery
+    sp<ISchedulingPolicyService> sps;
+    for (;;) {
+        sMutex.lock();
+        sps = sSchedulingPolicyService;
+        sMutex.unlock();
+        if (sps != 0) {
+            break;
+        }
+        sp<IBinder> binder = defaultServiceManager()->checkService(_scheduling_policy);
+        if (binder != 0) {
+            sps = interface_cast<ISchedulingPolicyService>(binder);
+            sMutex.lock();
+            sSchedulingPolicyService = sps;
+            sMutex.unlock();
+            break;
+        }
+        sleep(1);
+    }
+    return sps->requestPriority(pid, tid, prio);
+}
+
+}   // namespace android