Merge "Fix: read memory.stat from per-app cgroup only if per-app memcg are enabled on a device" (ca56622d) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/am/MemoryStatUtil.java

+8 −11

Original line number	Diff line number	Diff line
		@@ -22,6 +22,7 @@ import static com.android.server.am.ActivityManagerDebugConfig.TAG_WITH_CLASS_NA

		import android.annotation.Nullable;
		import android.os.FileUtils;
		import android.os.SystemProperties;
		import android.util.Slog;

		import com.android.internal.annotations.VisibleForTesting;
		@@ -38,6 +39,10 @@ import java.util.regex.Pattern;
		final class MemoryStatUtil {
		private static final String TAG = TAG_WITH_CLASS_NAME ? "MemoryStatUtil" : TAG_AM;

		/** True if device has per-app memcg */
		private static final Boolean DEVICE_HAS_PER_APP_MEMCG =
		SystemProperties.getBoolean("ro.config.per_app_memcg", false);

		/** Path to check if device has memcg */
		private static final String MEMCG_TEST_PATH = "/dev/memcg/apps/memory.stat";
		/** Path to memory stat file for logging app start memory state */
		@@ -55,15 +60,12 @@ final class MemoryStatUtil {
		private static final int PGMAJFAULT_INDEX = 11;
		private static final int RSS_IN_BYTES_INDEX = 23;

		/** True if device has memcg */
		private static volatile Boolean sDeviceHasMemCg;

		private MemoryStatUtil() {}

		/**
		* Reads memory stat for a process.
		*
		* Reads from memcg if available on device, else fallback to procfs.
		* Reads from per-app memcg if available on device, else fallback to procfs.
		* Returns null if no stats can be read.
		*/
		@Nullable
		@@ -156,15 +158,10 @@ final class MemoryStatUtil {
		}

		/**
		* Checks if memcg is available on device.
		*
		* Touches the filesystem to do the check.
		* Returns whether per-app memcg is available on device.
		*/
		static boolean hasMemcg() {
		if (sDeviceHasMemCg == null) {
		sDeviceHasMemCg = (new File(MEMCG_TEST_PATH)).exists();
		}
		return sDeviceHasMemCg;
		return DEVICE_HAS_PER_APP_MEMCG;
		}

		static final class MemoryStat {