Adjust Java Language thread priority in new processes.

am: 80993a6e60

Change-Id: I9fc2a68681eb3f39980c45f707581c3a19cdf0d4

3 files changed, 21 insertions, 3 deletions

diff --git a/core/java/com/android/internal/os/Zygote.java b/core/java/com/android/internal/os/Zygote.java
index 84ff5b88a3ae..55a70284a5bf 100644
--- a/core/java/com/android/internal/os/Zygote.java
+++ b/core/java/com/android/internal/os/Zygote.java
@@ -654,6 +654,9 @@ public final class Zygote {
             // End of the postFork event.
             Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
 
+            // Set the Java Language thread priority to the default value for new apps.
+            Thread.currentThread().setPriority(Thread.NORM_PRIORITY);
+
             return ZygoteInit.zygoteInit(args.mTargetSdkVersion,
                     args.mDisabledCompatChanges,
                     args.mRemainingArgs,
diff --git a/core/java/com/android/internal/os/ZygoteConnection.java b/core/java/com/android/internal/os/ZygoteConnection.java
index 2666d5278a90..4c5bb2ade0aa 100644
--- a/core/java/com/android/internal/os/ZygoteConnection.java
+++ b/core/java/com/android/internal/os/ZygoteConnection.java
@@ -487,6 +487,9 @@ class ZygoteConnection {
 
         Zygote.setAppProcessName(parsedArgs, TAG);
 
+        // Set the Java Language thread priority to the default value for new apps.
+        Thread.currentThread().setPriority(Thread.NORM_PRIORITY);
+
         // End of the postFork event.
         Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
         if (parsedArgs.mInvokeWith != null) {
diff --git a/core/java/com/android/internal/os/ZygoteInit.java b/core/java/com/android/internal/os/ZygoteInit.java
index f870d0a9257d..4a33bc2f252a 100644
--- a/core/java/com/android/internal/os/ZygoteInit.java
+++ b/core/java/com/android/internal/os/ZygoteInit.java
@@ -518,6 +518,9 @@ public class ZygoteInit {
             }
         }
 
+        // Set the Java Language thread priority to the default value for the system server.
+        Thread.currentThread().setPriority(Thread.NORM_PRIORITY);
+
         if (parsedArgs.mInvokeWith != null) {
             String[] args = parsedArgs.mRemainingArgs;
             // If we have a non-null system server class path, we'll have to duplicate the
@@ -825,13 +828,22 @@ public class ZygoteInit {
         return result;
     }
 
+    /**
+     * This is the entry point for a Zygote process.  It creates the Zygote server, loads resources,
+     * and handles other tasks related to preparing the process for forking into applications.
+     *
+     * This process is started with a nice value of -20 (highest priority).  All paths that flow
+     * into new processes are required to either set the priority to the default value or terminate
+     * before executing any non-system code.  The native side of this occurs in SpecializeCommon,
+     * while the Java Language priority is changed in ZygoteInit.handleSystemServerProcess,
+     * ZygoteConnection.handleChildProc, and Zygote.usapMain.
+     *
+     * @param argv  Command line arguments used to specify the Zygote's configuration.
+     */
     @UnsupportedAppUsage
     public static void main(String argv[]) {
         ZygoteServer zygoteServer = null;
 
-        // Set the initial thread priority to the "normal" value.
-        Thread.currentThread().setPriority(Thread.NORM_PRIORITY);
-
         // Mark zygote start. This ensures that thread creation will throw
         // an error.
         ZygoteHooks.startZygoteNoThreadCreation();