Merge "Disable tracing from Zygote" into jb-mr2-dev (95a869f9) · Commits · e / os / android_frameworks_base

cmds/app_process/app_main.cpp

+4 −0

Original line number	Diff line number	Diff line
		@@ -12,6 +12,7 @@
		#include <utils/Log.h>
		#include <cutils/process_name.h>
		#include <cutils/memory.h>
		#include <cutils/trace.h>
		#include <android_runtime/AndroidRuntime.h>
		#include <sys/personality.h>

		@@ -95,6 +96,9 @@ public:

		virtual void onZygoteInit()
		{
		// Re-enable tracing now that we're no longer in Zygote.
		atrace_set_tracing_enabled(true);

		sp<ProcessState> proc = ProcessState::self();
		ALOGV("App process: starting thread pool.\n");
		proc->startThreadPool();

core/java/android/os/Trace.java

+17 −4

Original line number	Diff line number	Diff line
		@@ -79,6 +79,7 @@ public final class Trace {
		private static native void nativeAsyncTraceBegin(long tag, String name, int cookie);
		private static native void nativeAsyncTraceEnd(long tag, String name, int cookie);
		private static native void nativeSetAppTracingAllowed(boolean allowed);
		private static native void nativeSetTracingEnabled(boolean allowed);

		static {
		// We configure two separate change callbacks, one in Trace.cpp and one here. The
		@@ -115,10 +116,6 @@ public final class Trace {
		*/
		private static long cacheEnabledTags() {
		long tags = nativeGetEnabledTags();
		if (tags == TRACE_TAG_NOT_READY) {
		Log.w(TAG, "Unexpected value from nativeGetEnabledTags: " + tags);
		// keep going
		}
		sEnabledTags = tags;
		return tags;
		}
		@@ -168,6 +165,22 @@ public final class Trace {
		cacheEnabledTags();
		}

		/**
		* Set whether tracing is enabled in this process. Tracing is disabled shortly after Zygote
		* initializes and re-enabled after processes fork from Zygote. This is done because Zygote
		* has no way to be notified about changes to the tracing tags, and if Zygote ever reads and
		* caches the tracing tags, forked processes will inherit those stale tags.
		*
		* @hide
		*/
		public static void setTracingEnabled(boolean enabled) {
		nativeSetTracingEnabled(enabled);

		// Setting whether tracing is enabled may change the tags, so we update the cached tags
		// here.
		cacheEnabledTags();
		}

		/**
		* Writes a trace message to indicate that a given section of code has
		* begun. Must be followed by a call to {@link #traceEnd} using the same

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

+5 −0

Original line number	Diff line number	Diff line
		@@ -25,6 +25,7 @@ import android.net.LocalServerSocket;
		import android.os.Debug;
		import android.os.Process;
		import android.os.SystemClock;
		import android.os.Trace;
		import android.util.EventLog;
		import android.util.Log;

		@@ -528,6 +529,10 @@ public class ZygoteInit {
		// Do an initial gc to clean up after startup
		gc();

		// Disable tracing so that forked processes do not inherit stale tracing tags from
		// Zygote.
		Trace.setTracingEnabled(false);

		// If requested, start system server directly from Zygote
		if (argv.length != 2) {
		throw new RuntimeException(argv[0] + USAGE_STRING);

core/jni/android_os_Trace.cpp

+8 −0

Original line number	Diff line number	Diff line
		@@ -86,6 +86,11 @@ static void android_os_Trace_nativeSetAppTracingAllowed(JNIEnv* env,
		atrace_set_debuggable(allowed);
		}

		static void android_os_Trace_nativeSetTracingEnabled(JNIEnv* env,
		jclass clazz, jboolean enabled) {
		atrace_set_tracing_enabled(enabled);
		}

		static JNINativeMethod gTraceMethods[] = {
		/* name, signature, funcPtr */
		{ "nativeGetEnabledTags",
		@@ -109,6 +114,9 @@ static JNINativeMethod gTraceMethods[] = {
		{ "nativeSetAppTracingAllowed",
		"(Z)V",
		(void*)android_os_Trace_nativeSetAppTracingAllowed },
		{ "nativeSetTracingEnabled",
		"(Z)V",
		(void*)android_os_Trace_nativeSetTracingEnabled },
		};

		int register_android_os_Trace(JNIEnv* env) {