From eef4a3d53cadaab782944923577d6aca7b7ba5c8 Mon Sep 17 00:00:00 2001
From: Tim Murray <timmurray@google.com>
Date: Tue, 19 Apr 2016 14:14:20 -0700
Subject: [PATCH] Increase the max binder thread pool size for system_server.

bug 28201939

Change-Id: Iaade417a26247970b96f0aaacb3844d72de6399c
---
 core/java/com/android/internal/os/BinderInternal.java | 2 ++
 core/jni/android_util_Binder.cpp                      | 7 +++++++
 services/java/com/android/server/SystemServer.java    | 7 +++++++
 3 files changed, 16 insertions(+)

diff --git a/core/java/com/android/internal/os/BinderInternal.java b/core/java/com/android/internal/os/BinderInternal.java
index d77b998fa247b..ea4575aba9c0b 100644
--- a/core/java/com/android/internal/os/BinderInternal.java
+++ b/core/java/com/android/internal/os/BinderInternal.java
@@ -93,6 +93,8 @@ public class BinderInternal {
      * @hide
      */
     public static final native void disableBackgroundScheduling(boolean disable);
+
+    public static final native void setMaxThreads(int numThreads);
     
     static native final void handleGc();
     
diff --git a/core/jni/android_util_Binder.cpp b/core/jni/android_util_Binder.cpp
index abc6c4b5e7cc0..5559d48a58b65 100644
--- a/core/jni/android_util_Binder.cpp
+++ b/core/jni/android_util_Binder.cpp
@@ -917,6 +917,12 @@ static void android_os_BinderInternal_disableBackgroundScheduling(JNIEnv* env,
     IPCThreadState::disableBackgroundScheduling(disable ? true : false);
 }
 
+static void android_os_BinderInternal_setMaxThreads(JNIEnv* env,
+        jobject clazz, jint maxThreads)
+{
+    ProcessState::self()->setThreadPoolMaxThreadCount(maxThreads);
+}
+
 static void android_os_BinderInternal_handleGc(JNIEnv* env, jobject clazz)
 {
     ALOGV("Gc has executed, clearing binder ops");
@@ -930,6 +936,7 @@ static const JNINativeMethod gBinderInternalMethods[] = {
     { "getContextObject", "()Landroid/os/IBinder;", (void*)android_os_BinderInternal_getContextObject },
     { "joinThreadPool", "()V", (void*)android_os_BinderInternal_joinThreadPool },
     { "disableBackgroundScheduling", "(Z)V", (void*)android_os_BinderInternal_disableBackgroundScheduling },
+    { "setMaxThreads", "(I)V", (void*)android_os_BinderInternal_setMaxThreads },
     { "handleGc", "()V", (void*)android_os_BinderInternal_handleGc }
 };
 
diff --git a/services/java/com/android/server/SystemServer.java b/services/java/com/android/server/SystemServer.java
index 8c2f559677c48..9f2ca591e6efc 100644
--- a/services/java/com/android/server/SystemServer.java
+++ b/services/java/com/android/server/SystemServer.java
@@ -165,6 +165,10 @@ public final class SystemServer {
     private static final String UNCRYPT_PACKAGE_FILE = "/cache/recovery/uncrypt_file";
     private static final String BLOCK_MAP_FILE = "/cache/recovery/block.map";
 
+    // maximum number of binder threads used for system_server
+    // will be higher than the system default
+    private static final int sMaxBinderThreads = 31;
+
     /**
      * Default theme used by the system context. This is used to style
      * system-provided dialogs, such as the Power Off dialog, and other
@@ -285,6 +289,9 @@ public final class SystemServer {
             // Ensure binder calls into the system always run at foreground priority.
             BinderInternal.disableBackgroundScheduling(true);
 
+            // Increase the number of binder threads in system_server
+            BinderInternal.setMaxThreads(sMaxBinderThreads);
+
             // Prepare the main looper thread (this thread).
             android.os.Process.setThreadPriority(
                 android.os.Process.THREAD_PRIORITY_FOREGROUND);