Adds Zygote policy flags to control how applications are launched

This patch adds a zygote policy parameter to functions in the
ActivityManagerService (and associated classes) to allow for different
launch behavior based on the triggering event.  This will allow for
latency sensitive applications to utilize the Unspecialized App Process
Pool, without other processes draining the pool and causing excessive
refill events.

Test: Booted and launched several apps
Bug: 147613193
Change-Id: Ib0a51c8720f95a7eafcab4ad2b5bb08f27a58d8c
(cherry picked from commit 4d0518858881d94c3366ab6b709195bdaeee90be)

1 files changed, 39 insertions, 3 deletions

diff --git a/core/java/android/os/Process.java b/core/java/android/os/Process.java
index dbe3b7bd1794..d7af1b9faa97 100644
--- a/core/java/android/os/Process.java
+++ b/core/java/android/os/Process.java
@@ -529,6 +529,40 @@ public class Process {
     private static int sPidFdSupported = PIDFD_UNKNOWN;
 
     /**
+     * Value used to indicate that there is no special information about an application launch.  App
+     * launches with this policy will occur through the primary or secondary Zygote with no special
+     * treatment.
+     *
+     * @hide
+     */
+    public static final int ZYGOTE_POLICY_FLAG_EMPTY = 0;
+
+    /**
+     * Flag used to indicate that an application launch is user-visible and latency sensitive.  Any
+     * launch with this policy will use a Unspecialized App Process Pool if the target Zygote
+     * supports it.
+     *
+     * @hide
+     */
+    public static final int ZYGOTE_POLICY_FLAG_LATENCY_SENSITIVE = 1 << 0;
+
+    /**
+     * Flag used to indicate that the launch is one in a series of app launches that will be
+     * performed in quick succession.  For future use.
+     *
+     * @hide
+     */
+    public static final int ZYGOTE_POLICY_FLAG_BATCH_LAUNCH = 1 << 1;
+
+    /**
+     * Flag used to indicate that the current launch event is for a system process.  All system
+     * processes are equally important, so none of them should be prioritized over the others.
+     *
+     * @hide
+     */
+    public static final int ZYGOTE_POLICY_FLAG_SYSTEM_PROCESS = 1 << 2;
+
+    /**
      * State associated with the zygote process.
      * @hide
      */
@@ -567,6 +601,7 @@ public class Process {
      * @param appDataDir null-ok the data directory of the app.
      * @param invokeWith null-ok the command to invoke with.
      * @param packageName null-ok the name of the package this process belongs to.
+     * @param zygotePolicyFlags Flags used to determine how to launch the application
      * @param isTopApp whether the process starts for high priority application.
      * @param disabledCompatChanges null-ok list of disabled compat changes for the process being
      *                             started.
@@ -590,6 +625,7 @@ public class Process {
                                            @Nullable String appDataDir,
                                            @Nullable String invokeWith,
                                            @Nullable String packageName,
+                                           int zygotePolicyFlags,
                                            boolean isTopApp,
                                            @Nullable long[] disabledCompatChanges,
                                            @Nullable Map<String, Pair<String, Long>>
@@ -598,7 +634,7 @@ public class Process {
         return ZYGOTE_PROCESS.start(processClass, niceName, uid, gid, gids,
                     runtimeFlags, mountExternal, targetSdkVersion, seInfo,
                     abi, instructionSet, appDataDir, invokeWith, packageName,
-                    /*useUsapPool=*/ true, isTopApp, disabledCompatChanges,
+                    zygotePolicyFlags, isTopApp, disabledCompatChanges,
                     pkgDataInfoMap, zygoteArgs);
     }
 
@@ -622,8 +658,8 @@ public class Process {
         return WebViewZygote.getProcess().start(processClass, niceName, uid, gid, gids,
                     runtimeFlags, mountExternal, targetSdkVersion, seInfo,
                     abi, instructionSet, appDataDir, invokeWith, packageName,
-                    /*useUsapPool=*/ false, /*isTopApp=*/ false, disabledCompatChanges,
-                    /* pkgDataInfoMap */ null, zygoteArgs);
+                    /*zygotePolicyFlags=*/ ZYGOTE_POLICY_FLAG_EMPTY, /*isTopApp=*/ false,
+                disabledCompatChanges, /* pkgDataInfoMap */ null, zygoteArgs);
     }
 
     /**