Merge "Boost Zygote to fifo for top-app forks when using fifo ui" into main (e3f2406b) · Commits · e / os / android_frameworks_base

core/java/com/android/internal/os/Zygote.java

+7 −3

Original line number	Diff line number	Diff line
		@@ -373,9 +373,11 @@ public final class Zygote {
		boolean bindMountSyspropOverrides) {
		ZygoteHooks.preFork();

		boolean useFifoUi = SystemProperties.getInt("sys.use_fifo_ui", 0) == 1;
		int pid = nativeForkAndSpecialize(
		uid, gid, gids, runtimeFlags, rlimits, mountExternal, seInfo, niceName, fdsToClose,
		fdsToIgnore, startChildZygote, instructionSet, appDataDir, isTopApp,
		com.android.internal.os.Flags.zygoteEarlyFifoBoost() ? useFifoUi : false,
		pkgDataInfoList, allowlistedDataInfoList, bindMountAppDataDirs,
		bindMountAppStorageDirs, bindMountSyspropOverrides);
		if (pid == 0) {
		@@ -398,7 +400,7 @@ public final class Zygote {
		private static native int nativeForkAndSpecialize(int uid, int gid, int[] gids,
		int runtimeFlags, int[][] rlimits, int mountExternal, String seInfo, String niceName,
		int[] fdsToClose, int[] fdsToIgnore, boolean startChildZygote, String instructionSet,
		String appDataDir, boolean isTopApp, String[] pkgDataInfoList,
		String appDataDir, boolean isTopApp, boolean useFifoUi, String[] pkgDataInfoList,
		String[] allowlistedDataInfoList, boolean bindMountAppDataDirs,
		boolean bindMountAppStorageDirs, boolean bindMountSyspropOverrides);

		@@ -730,9 +732,11 @@ public final class Zygote {
		@NonNull FileDescriptor zygoteSocket,
		int expectedUid,
		int minUid,
		@Nullable String firstNiceName) {
		@Nullable String firstNiceName,
		boolean isTopApp) {
		boolean in_child =
		argBuffer.forkRepeatedly(zygoteSocket, expectedUid, minUid, firstNiceName);
		argBuffer.forkRepeatedly(zygoteSocket, expectedUid, minUid, firstNiceName,
		isTopApp);
		if (in_child) {
		return childMain(argBuffer, /usapPoolSocket=/null, /writePipe=/null);
		} else {

core/java/com/android/internal/os/ZygoteCommandBuffer.java

+8 −3

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@ package com.android.internal.os;
		import android.annotation.NonNull;
		import android.annotation.Nullable;
		import android.net.LocalSocket;
		import android.os.SystemProperties;

		import java.io.FileDescriptor;
		import java.lang.ref.Reference; // For reachabilityFence.
		@@ -164,10 +165,12 @@ class ZygoteCommandBuffer implements AutoCloseable {
		* at the beginning of a command that still needs to be processed.
		*/
		boolean forkRepeatedly(FileDescriptor zygoteSocket, int expectedUid, int minUid,
		String firstNiceName) {
		String firstNiceName, boolean isTopApp) {
		try {
		boolean useFifoUi = SystemProperties.getInt("sys.use_fifo_ui", 0) == 1;
		return nativeForkRepeatedly(mNativeBuffer, zygoteSocket.getInt$(),
		expectedUid, minUid, firstNiceName);
		expectedUid, minUid, firstNiceName, isTopApp,
		com.android.internal.os.Flags.zygoteEarlyFifoBoost() ? useFifoUi : false);
		} finally {
		Reference.reachabilityFence(mSocket);
		Reference.reachabilityFence(zygoteSocket);
		@@ -182,6 +185,8 @@ class ZygoteCommandBuffer implements AutoCloseable {
		int zygoteSocketRawFd,
		int expectedUid,
		int minUid,
		String firstNiceName);
		String firstNiceName,
		boolean isTopApp,
		boolean useFifoUi);

		}

core/java/com/android/internal/os/ZygoteConnection.java

+2 −1

Original line number	Diff line number	Diff line
		@@ -284,7 +284,8 @@ class ZygoteConnection {
		ZygoteHooks.preFork();
		Runnable result = Zygote.forkSimpleApps(argBuffer,
		zygoteServer.getZygoteSocketFileDescriptor(),
		peer.getUid(), Zygote.minChildUid(peer), parsedArgs.mNiceName);
		peer.getUid(), Zygote.minChildUid(peer), parsedArgs.mNiceName,
		parsedArgs.mIsTopApp);
		if (result == null) {
		// parent; we finished some number of forks. Result is Boolean.
		// We already did the equivalent of handleParentProc().

core/java/com/android/internal/os/flags.aconfig

+8 −0

Original line number	Diff line number	Diff line
		@@ -60,3 +60,11 @@ flag {
		purpose: PURPOSE_BUGFIX
		}
		}

		flag {
		name: "zygote_early_fifo_boost"
		namespace: "watch_software_performance"
		description: "Enables zygote boosting to fifo priority for top-app launches when fifo_ui is enabled"
		bug: "397918406"
		is_fixed_read_only: true
		}

core/jni/com_android_internal_os_Zygote.cpp

+59 −12

Original line number	Diff line number	Diff line
		@@ -2432,9 +2432,30 @@ pid_t zygote::ForkCommon(JNIEnv* env, bool is_system_server,
		const std::vector<int>& fds_to_close,
		const std::vector<int>& fds_to_ignore,
		bool is_priority_fork,
		bool is_top_app,
		bool use_fifo_ui,
		bool purge) {
		ATRACE_CALL();
		if (is_priority_fork) {
		/*
		* Number of processors configured on the device.
		*/
		static int number_of_processors = sysconf(_SC_NPROCESSORS_CONF);

		if (is_top_app && use_fifo_ui) {
		// Set SCHED_FIFO for top-app fork where FIFO UI is enabled.
		struct sched_param rt_param;
		rt_param.sched_priority = 1; // 98 prio

		if (number_of_processors == 1) {
		RuntimeAbort(env, __LINE__, "Cannot set SCHED_FIFO on single-core devices.");
		}

		if (sched_setscheduler(0, SCHED_FIFO, &rt_param) != 0) {
		ALOGE("Failed to set SCHED_FIFO: %s", strerror(errno));
		} else {
		ALOGW("Setting SCHED_FIFO for top-app fork");
		}
		} else if (is_priority_fork) {
		setpriority(PRIO_PROCESS, 0, PROCESS_PRIORITY_MAX);
		}

		@@ -2485,9 +2506,22 @@ pid_t zygote::ForkCommon(JNIEnv* env, bool is_system_server,
		pid_t pid = fork();

		if (pid == 0) {
		if (is_priority_fork) {
		if (is_top_app && use_fifo_ui) {
		// Explicitly set SCHED_FIFO \| SCHED_RESET_ON_FORK for child's main thread to avoid other
		// threads inheriting the main thread's FIFO scheduling policy.
		// Empirically, SCHED_RESET_ON_FORK also applies to newly created threads.
		// An app shall have no more than the main and render threads running at
		// FIFO priority, thus not saturating the device with SCHED_FIFO tasks.
		struct sched_param child_rt_param = {0};
		child_rt_param.sched_priority = 1; // 98 prio
		if (sched_setscheduler(0, SCHED_FIFO \| SCHED_RESET_ON_FORK, &child_rt_param) != 0) {
		ALOGE("Failed to set SCHED_FIFO \| SCHED_RESET_ON_FORK: %s", strerror(errno));
		RuntimeAbort(env, __LINE__, "Failed to set SCHED_FIFO \| SCHED_RESET_ON_FORK in child");
		}
		} else if (is_priority_fork) {
		setpriority(PRIO_PROCESS, 0, PROCESS_PRIORITY_MAX);
		} else {
		// TODO: Revisit this.
		setpriority(PRIO_PROCESS, 0, PROCESS_PRIORITY_MIN);
		}

		@@ -2523,7 +2557,17 @@ pid_t zygote::ForkCommon(JNIEnv* env, bool is_system_server,
		// We blocked SIGCHLD prior to a fork, we unblock it here.
		UnblockSignal(SIGCHLD, fail_fn);

		if (is_priority_fork && pid != 0) {
		if (is_top_app && use_fifo_ui && pid != 0) {
		// Reset the scheduler to SCHED_OTHER for the Zygote process.
		struct sched_param zero_param = {0};
		if (sched_setscheduler(0, SCHED_OTHER, &zero_param) != 0) {
		ALOGE("Failed to reset scheduler: %s", strerror(errno));
		RuntimeAbort(env, __LINE__, "Failed to reset scheduler");
		} else {
		ALOGD("Reset scheduler to SCHED_OTHER");
		}
		setpriority(PRIO_PROCESS, 0, PROCESS_PRIORITY_DEFAULT);
		} else if (is_priority_fork && pid != 0) {
		setpriority(PRIO_PROCESS, 0, PROCESS_PRIORITY_DEFAULT);
		}

		@@ -2539,7 +2583,7 @@ static jint com_android_internal_os_Zygote_nativeForkAndSpecialize(
		JNIEnv* env, jclass, jint uid, jint gid, jintArray gids, jint runtime_flags,
		jobjectArray rlimits, jint mount_external, jstring se_info, jstring nice_name,
		jintArray managed_fds_to_close, jintArray managed_fds_to_ignore, jboolean is_child_zygote,
		jstring instruction_set, jstring app_data_dir, jboolean is_top_app,
		jstring instruction_set, jstring app_data_dir, jboolean is_top_app, jboolean use_fifo_ui,
		jobjectArray pkg_data_info_list, jobjectArray allowlisted_data_info_list,
		jboolean mount_data_dirs, jboolean mount_storage_dirs, jboolean mount_sysprop_overrides) {
		jlong capabilities = CalculateCapabilities(env, uid, gid, gids, is_child_zygote);
		@@ -2578,7 +2622,7 @@ static jint com_android_internal_os_Zygote_nativeForkAndSpecialize(
		}

		pid_t pid = zygote::ForkCommon(env, /* is_system_server= */ false, fds_to_close, fds_to_ignore,
		true);
		true, is_top_app == JNI_TRUE, use_fifo_ui == JNI_TRUE);

		if (pid == 0) {
		SpecializeCommon(env, uid, gid, gids, runtime_flags, rlimits, capabilities, capabilities,
		@@ -2668,7 +2712,8 @@ static jint com_android_internal_os_Zygote_nativeForkApp(JNIEnv* env,
		ExtractJIntArray(env, "USAP", nullptr, managed_session_socket_fds)
		.value_or(std::vector<int>());
		return zygote::forkApp(env, read_pipe_fd, write_pipe_fd, session_socket_fds,
		args_known == JNI_TRUE, is_priority_fork == JNI_TRUE, true);
		args_known == JNI_TRUE, is_priority_fork == JNI_TRUE,
		false, false, true);
		}

		NO_STACK_PROTECTOR
		@@ -2678,6 +2723,8 @@ int zygote::forkApp(JNIEnv* env,
		const std::vector<int>& session_socket_fds,
		bool args_known,
		bool is_priority_fork,
		bool is_top_app,
		bool use_fifo_ui,
		bool purge) {
		ATRACE_CALL();

		@@ -2718,7 +2765,7 @@ int zygote::forkApp(JNIEnv* env,
		}

		return zygote::ForkCommon(env, /* is_system_server= */ false, fds_to_close,
		fds_to_ignore, is_priority_fork == JNI_TRUE, purge);
		fds_to_ignore, is_priority_fork, is_top_app, use_fifo_ui, purge);
		}

		static void com_android_internal_os_Zygote_nativeAllowFileAcrossFork(
		@@ -3055,7 +3102,7 @@ static void com_android_internal_os_Zygote_nativeAllowFilesOpenedByPreload(JNIEn
		static const JNINativeMethod gMethods[] = {
		{"nativeForkAndSpecialize",
		"(II[II[[IILjava/lang/String;Ljava/lang/String;[I[IZLjava/lang/String;Ljava/lang/"
		"String;Z[Ljava/lang/String;[Ljava/lang/String;ZZZ)I",
		"String;ZZ[Ljava/lang/String;[Ljava/lang/String;ZZZ)I",
		(void*)com_android_internal_os_Zygote_nativeForkAndSpecialize},
		{"nativeForkSystemServer", "(II[II[[IJJ)I",
		(void*)com_android_internal_os_Zygote_nativeForkSystemServer},