Pass latency information from app to input
Once the app learns about the frame's timeline, it will tell
inputdispatcher about it. We are adding a new callback similar to
'finishInputEvent', called 'reportLatencyInfo'.
This will tell inputdispatcher about the queue time and the present time
of each frame that was caused by input.
InputDispatcher will then be able to reconstruct the input event
timeline and report the end-to-end latency metrics.
In a separate CL, we will add LatencyTracker, which will eventually
receive this data.
Using the event id and the provided queue time and present time, we will
be able to reconstruct the end-to-end latency inside LatencyTracker.
Bug: 167947340
Test: atest inputflinger_tests libinput_tests
Change-Id: I181532a01b34eecd186bc3c74db289fc59c5955c
diff --git a/include/input/InputTransport.h b/include/input/InputTransport.h
index 3e5674e..898d1a9 100644
--- a/include/input/InputTransport.h
+++ b/include/input/InputTransport.h
@@ -71,6 +71,7 @@
FOCUS,
CAPTURE,
DRAG,
+ TIMELINE,
};
struct Header {
@@ -195,6 +196,14 @@
inline size_t size() const { return sizeof(Drag); }
} drag;
+
+ struct Timeline {
+ int32_t eventId;
+ uint32_t empty;
+ std::array<nsecs_t, GraphicsTimeline::SIZE> graphicsTimeline;
+
+ inline size_t size() const { return sizeof(Timeline); }
+ } timeline;
} __attribute__((aligned(8))) body;
bool isValid(size_t actualSize) const;
@@ -381,10 +390,25 @@
nsecs_t consumeTime;
};
- /* Receives the finished signal from the consumer in reply to the original dispatch signal.
- * If a signal was received, returns a Finished object.
+ struct Timeline {
+ int32_t inputEventId;
+ std::array<nsecs_t, GraphicsTimeline::SIZE> graphicsTimeline;
+ };
+
+ typedef std::variant<Finished, Timeline> ConsumerResponse;
+ /* Receive a signal from the consumer in reply to the original dispatch signal.
+ * If a signal was received, returns a Finished or a Timeline object.
+ * The InputConsumer should return a Finished object for every InputMessage that it is sent
+ * to confirm that it has been processed and that the InputConsumer is responsive.
+ * If several InputMessages are sent to InputConsumer, it's possible to receive Finished
+ * events out of order for those messages.
*
- * The returned sequence number is never 0 unless the operation failed.
+ * The Timeline object is returned whenever the receiving end has processed a graphical frame
+ * and is returning the timeline of the frame. Not all input events will cause a Timeline
+ * object to be returned, and there is not guarantee about when it will arrive.
+ *
+ * If an object of Finished is returned, the returned sequence number is never 0 unless the
+ * operation failed.
*
* Returned error codes:
* OK on success.
@@ -392,7 +416,7 @@
* DEAD_OBJECT if the channel's peer has been closed.
* Other errors probably indicate that the channel is broken.
*/
- android::base::Result<Finished> receiveFinishedSignal();
+ android::base::Result<ConsumerResponse> receiveConsumerResponse();
private:
std::shared_ptr<InputChannel> mChannel;
@@ -448,6 +472,9 @@
*/
status_t sendFinishedSignal(uint32_t seq, bool handled);
+ status_t sendTimeline(int32_t inputEventId,
+ std::array<nsecs_t, GraphicsTimeline::SIZE> timeline);
+
/* Returns true if there is a deferred event waiting.
*
* Should be called after calling consume() to determine whether the consumer