Set Realtime Audio Thread priority on Android

base/threading/platform_thread_posix.cc

Index: base/threading/platform_thread_posix.cc
diff --git a/base/threading/platform_thread_posix.cc b/base/threading/platform_thread_posix.cc
index 444edc58a6268649115f2f1583bc7b56374d961d..e5b77981f64a54a479fd2a30ef4f256d84c84f57 100644
--- a/base/threading/platform_thread_posix.cc
+++ b/base/threading/platform_thread_posix.cc
@@ -30,6 +30,7 @@
 
 #if defined(OS_ANDROID)
 #include "base/android/jni_android.h"
+#include "jni/ThreadUtils_jni.h"
 #endif
 
 // TODO(bbudge) Use time.h when NaCl toolchain supports _POSIX_TIMERS
@@ -274,13 +275,33 @@ void PlatformThread::Join(PlatformThreadHandle thread_handle) {
   pthread_join(thread_handle, NULL);
 }
 
-#if !defined(OS_MACOSX)
-// Mac OS X uses lower-level mach APIs.
-
+#if !defined(OS_MACOSX) && !defined(OS_ANDROID)
+// Mac OS X uses lower-level mach APIs and Android uses Java APIs.
 // static
 void PlatformThread::SetThreadPriority(PlatformThreadHandle, ThreadPriority) {
   // TODO(crogers): Implement, see http://crbug.com/116172
 }
 #endif
 
+#if defined(OS_ANDROID)
+bool RegisterThreadUtils(JNIEnv* env) {
+    return RegisterNativesImpl(env);
+}
+
+void PlatformThread::SetThreadPriority(PlatformThreadHandle,
+                                       ThreadPriority priority) {
+  // Use Android SDK API to set priority for real time audio thread and it will
+  // set the thread to corresponding cgroups.
+  if (priority == kThreadPriority_RealtimeAudio) {
+    JNIEnv* env = base::android::AttachCurrentThread();
+    // Keep consistent with android.os.Process.THREAD_PRIORITY_AUDIO.
+    const int kThreadPriorityAudio = -16;

[qinmin, 2013/01/07 19:16:34]

There is no need to define this variable here and pass it to the java side. You
can get the value at java side and set it there. Maybe change the java side call
to setAudioThreadPriority.

[Wei James(wistoch), 2013/01/08 02:42:37]

fixed. thanks

+    Java_ThreadUtils_setThreadPriority(env, PlatformThread::CurrentId(),
+                                       kThreadPriorityAudio);
+  } else {
+    NOTREACHED() << "Unknown thread priority.";
+  }
+}
+#endif
+
 }  // namespace base