Merge "cutils: trace: add atrace_update_tags()" (3fc2b89a) · Commits · e / os / android_system_core

include/cutils/trace.h

+6 −0

Original line number	Diff line number	Diff line
		@@ -85,6 +85,12 @@ __BEGIN_DECLS
		*/
		void atrace_setup();

		/**
		* If tracing is ready, set atrace_enabled_tags to the system property
		* debug.atrace.tags.enableflags. Can be used as a sysprop change callback.
		*/
		void atrace_update_tags();

		/**
		* Flag indicating whether setup has been completed, initialized to 0.
		* Nonzero indicates setup has completed.

+13 −0

Original line number	Diff line number	Diff line
		@@ -33,6 +33,7 @@ int32_t atrace_is_ready = 0;
		int atrace_marker_fd = -1;
		uint64_t atrace_enabled_tags = ATRACE_TAG_NOT_READY;
		static pthread_once_t atrace_once_control = PTHREAD_ONCE_INIT;
		static pthread_mutex_t atrace_tags_mutex = PTHREAD_MUTEX_INITIALIZER;

		// Read the sysprop and return the value tags should be set to
		static uint64_t atrace_get_property()
		@@ -54,6 +55,18 @@ static uint64_t atrace_get_property()
		return (tags \| ATRACE_TAG_ALWAYS) & ATRACE_TAG_VALID_MASK;
		}

		// Update tags if tracing is ready. Useful as a sysprop change callback.
		void atrace_update_tags()
		{
		uint64_t tags;
		if (CC_UNLIKELY(android_atomic_acquire_load(&atrace_is_ready))) {
		tags = atrace_get_property();
		pthread_mutex_lock(&atrace_tags_mutex);
		atrace_enabled_tags = tags;
		pthread_mutex_unlock(&atrace_tags_mutex);
		}
		}

		static void atrace_init_once()
		{
		atrace_marker_fd = open("/sys/kernel/debug/tracing/trace_marker", O_WRONLY);