Add blastula pool system properties
This patch adds the following properties to DeviceConfig:
* BLASTULA_POOL_ENABLED
* BLASTULA_POOL_SIZE_MAX
* BLASTULA_POOL_SIZE_MIN
* BLASTULA_POOL_REFILL_THERSHOLD
The BLASTULA_POOL_ENABLED property is checked by ZygoteProcess but not
currently used due to an existing bug (b/123409530). This will be
enabled by go/ag/6162164. Until then the code path is tested via log
inspection.
The remaining properties are checked by ZygoteServer. Values are
clamped to ensure that they cannot be set to values that are harmful to
the device.
Since device_config is not available in the Zygote the system properties
interface is used instead.
Bug: 123524494
Bug: 68253328
Test: adb shell device_config put runtime_native blastula_pool_enabled true
Test: manually verify the property change is observed
Change-Id: I2b675afd9fbc1cbb0e8bc1c491cfdbbb612d0d3b
diff --git a/core/java/com/android/internal/os/Zygote.java b/core/java/com/android/internal/os/Zygote.java
index 40d7868..22884ac 100644
--- a/core/java/com/android/internal/os/Zygote.java
+++ b/core/java/com/android/internal/os/Zygote.java
@@ -29,6 +29,7 @@
import android.os.Process;
import android.os.SystemProperties;
import android.os.Trace;
+import android.provider.DeviceConfig;
import android.system.ErrnoException;
import android.system.Os;
import android.util.Log;
@@ -129,21 +130,6 @@
public static final int BLASTULA_MANAGEMENT_MESSAGE_BYTES = 8;
/**
- * If the blastula pool should be created and used to start applications.
- *
- * Setting this value to false will disable the creation, maintenance, and use of the blastula
- * pool. When the blastula pool is disabled the application lifecycle will be identical to
- * previous versions of Android.
- */
- public static final boolean BLASTULA_POOL_ENABLED = false;
-
- /**
- * File descriptor used for communication between the signal handler and the ZygoteServer poll
- * loop.
- * */
- protected static FileDescriptor sBlastulaPoolEventFD;
-
- /**
* An extraArg passed when a zygote process is forking a child-zygote, specifying a name
* in the abstract socket namespace. This socket name is what the new child zygote
* should listen for connections on.
@@ -174,44 +160,40 @@
private static final String ANDROID_SOCKET_PREFIX = "ANDROID_SOCKET_";
/**
- * The maximum value that the sBlastulaPoolMax variable may take. This value
- * is a mirror of BLASTULA_POOL_MAX_LIMIT found in com_android_internal_os_Zygote.cpp.
+ * The duration to wait before re-checking Zygote related system properties.
+ *
+ * Five minutes in milliseconds.
*/
- static final int BLASTULA_POOL_MAX_LIMIT = 10;
-
- /**
- * The minimum value that the sBlastulaPoolMin variable may take.
- */
- static final int BLASTULA_POOL_MIN_LIMIT = 1;
-
- /**
- * The runtime-adjustable maximum Blastula pool size.
- */
- static int sBlastulaPoolMax = BLASTULA_POOL_MAX_LIMIT;
-
- /**
- * The runtime-adjustable minimum Blastula pool size.
- */
- static int sBlastulaPoolMin = BLASTULA_POOL_MIN_LIMIT;
-
- /**
- * The runtime-adjustable value used to determine when to re-fill the
- * blastula pool. The pool will be re-filled when
- * (sBlastulaPoolMax - gBlastulaPoolCount) >= sBlastulaPoolRefillThreshold.
- */
- // TODO (chriswailes): This must be updated at the same time as sBlastulaPoolMax.
- static int sBlastulaPoolRefillThreshold = (sBlastulaPoolMax / 2);
+ public static final long PROPERTY_CHECK_INTERVAL = 300000;
/**
* @hide for internal use only
*/
public static final int SOCKET_BUFFER_SIZE = 256;
- private static LocalServerSocket sBlastulaPoolSocket = null;
-
/** a prototype instance for a future List.toArray() */
protected static final int[][] INT_ARRAY_2D = new int[0][0];
+ /**
+ * @hide for internal use only.
+ */
+ public static final String PRIMARY_SOCKET_NAME = "zygote";
+
+ /**
+ * @hide for internal use only.
+ */
+ public static final String SECONDARY_SOCKET_NAME = "zygote_secondary";
+
+ /**
+ * @hide for internal use only
+ */
+ public static final String BLASTULA_POOL_PRIMARY_SOCKET_NAME = "blastula_pool";
+
+ /**
+ * @hide for internal use only
+ */
+ public static final String BLASTULA_POOL_SECONDARY_SOCKET_NAME = "blastula_pool_secondary";
+
private Zygote() {}
/** Called for some security initialization before any fork. */
@@ -428,70 +410,47 @@
protected static native void nativeGetSocketFDs(boolean isPrimary);
/**
- * Initialize the blastula pool and fill it with the desired number of
- * processes.
+ * Returns the raw string value of a system property.
+ *
+ * Note that Device Config is not available without an application so SystemProperties is used
+ * instead.
+ *
+ * TODO (chriswailes): Cache the system property location in native code and then write a JNI
+ * function to fetch it.
*/
- protected static Runnable initBlastulaPool() {
- if (BLASTULA_POOL_ENABLED) {
- sBlastulaPoolEventFD = getBlastulaPoolEventFD();
-
- return fillBlastulaPool(null);
- } else {
- return null;
- }
+ public static String getSystemProperty(String propertyName, String defaultValue) {
+ return SystemProperties.get(
+ String.join(".",
+ "persist.device_config",
+ DeviceConfig.RuntimeNative.NAMESPACE,
+ propertyName),
+ defaultValue);
}
/**
- * Checks to see if the current policy says that pool should be refilled, and spawns new
- * blastulas if necessary.
+ * Returns the value of a system property converted to a boolean using specific logic.
*
- * NOTE: This function doesn't need to be guarded with BLASTULA_POOL_ENABLED because it is
- * only called from contexts that are only valid if the pool is enabled.
+ * Note that Device Config is not available without an application so SystemProperties is used
+ * instead.
*
- * @param sessionSocketRawFDs Anonymous session sockets that are currently open
- * @return In the Zygote process this function will always return null; in blastula processes
- * this function will return a Runnable object representing the new application that is
- * passed up from blastulaMain.
+ * @see SystemProperties.getBoolean
+ *
+ * TODO (chriswailes): Cache the system property location in native code and then write a JNI
+ * function to fetch it.
*/
- protected static Runnable fillBlastulaPool(int[] sessionSocketRawFDs) {
- Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "Zygote:FillBlastulaPool");
-
- int blastulaPoolCount = getBlastulaPoolCount();
-
- int numBlastulasToSpawn = sBlastulaPoolMax - blastulaPoolCount;
-
- if (blastulaPoolCount < sBlastulaPoolMin
- || numBlastulasToSpawn >= sBlastulaPoolRefillThreshold) {
-
- // Disable some VM functionality and reset some system values
- // before forking.
- ZygoteHooks.preFork();
- resetNicePriority();
-
- while (blastulaPoolCount++ < sBlastulaPoolMax) {
- Runnable caller = forkBlastula(sessionSocketRawFDs);
-
- if (caller != null) {
- return caller;
- }
- }
-
- // Re-enable runtime services for the Zygote. Blastula services
- // are re-enabled in specializeBlastula.
- ZygoteHooks.postForkCommon();
-
- Log.i("zygote", "Filled the blastula pool. New blastulas: " + numBlastulasToSpawn);
- }
-
- Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
-
- return null;
+ public static boolean getSystemPropertyBoolean(String propertyName, Boolean defaultValue) {
+ return SystemProperties.getBoolean(
+ String.join(".",
+ "persist.device_config",
+ DeviceConfig.RuntimeNative.NAMESPACE,
+ propertyName),
+ defaultValue);
}
/**
* @return Number of blastulas currently in the pool
*/
- private static int getBlastulaPoolCount() {
+ static int getBlastulaPoolCount() {
return nativeGetBlastulaPoolCount();
}
@@ -501,7 +460,7 @@
* @return The event FD used for communication between the signal handler and the ZygoteServer
* poll loop
*/
- private static FileDescriptor getBlastulaPoolEventFD() {
+ static FileDescriptor getBlastulaPoolEventFD() {
FileDescriptor fd = new FileDescriptor();
fd.setInt$(nativeGetBlastulaPoolEventFD());
@@ -518,7 +477,8 @@
* this function will return a Runnable object representing the new application that is
* passed up from blastulaMain.
*/
- private static Runnable forkBlastula(int[] sessionSocketRawFDs) {
+ static Runnable forkBlastula(LocalServerSocket blastulaPoolSocket,
+ int[] sessionSocketRawFDs) {
FileDescriptor[] pipeFDs = null;
try {
@@ -532,7 +492,7 @@
if (pid == 0) {
IoUtils.closeQuietly(pipeFDs[0]);
- return blastulaMain(pipeFDs[1]);
+ return blastulaMain(blastulaPoolSocket, pipeFDs[1]);
} else {
// The read-end of the pipe will be closed by the native code.
// See removeBlastulaTableEntry();
@@ -553,7 +513,8 @@
* of the ZygoteServer.
* @return A runnable oject representing the new application.
*/
- static Runnable blastulaMain(FileDescriptor writePipe) {
+ private static Runnable blastulaMain(LocalServerSocket blastulaPoolSocket,
+ FileDescriptor writePipe) {
final int pid = Process.myPid();
LocalSocket sessionSocket = null;
@@ -563,7 +524,7 @@
while (true) {
try {
- sessionSocket = sBlastulaPoolSocket.accept();
+ sessionSocket = blastulaPoolSocket.accept();
BufferedReader blastulaReader =
new BufferedReader(new InputStreamReader(sessionSocket.getInputStream()));
@@ -611,7 +572,7 @@
System.exit(-1);
} finally {
IoUtils.closeQuietly(sessionSocket);
- IoUtils.closeQuietly(sBlastulaPoolSocket);
+ IoUtils.closeQuietly(blastulaPoolSocket);
}
try {
@@ -660,7 +621,7 @@
* exception if an invalid arugment is encountered.
* @param args The arguments to test
*/
- static void validateBlastulaCommand(ZygoteArguments args) {
+ private static void validateBlastulaCommand(ZygoteArguments args) {
if (args.mAbiListQuery) {
throw new IllegalArgumentException(BLASTULA_ERROR_PREFIX + "--query-abi-list");
} else if (args.mPidQuery) {
@@ -851,20 +812,6 @@
}
/**
- * Creates a managed object representing the Blastula pool socket that has
- * already been initialized and bound by init.
- *
- * TODO (chriswailes): Move the name selection logic into this function.
- *
- * @throws RuntimeException when open fails
- */
- static void createBlastulaSocket(String socketName) {
- if (BLASTULA_POOL_ENABLED && sBlastulaPoolSocket == null) {
- sBlastulaPoolSocket = createManagedSocketFromInitSocket(socketName);
- }
- }
-
- /**
* Creates a managed LocalServerSocket object using a file descriptor
* created by an init.rc script. The init scripts that specify the
* sockets name can be found in system/core/rootdir. The socket is bound