commit 09979fbee7201b46158c2c033194529e4284ea13
author John Reck <jreck@google.com> Mon Mar 12 17:14:53 2018 -0700
committer John Reck <jreck@google.com> Wed Mar 14 15:00:05 2018 -0700
tree c86118e20004c9b9bd93f22171f6b4984fcbcef2
parent c1756316708216a0cef3394b8751a9d35dd30e1b

Break down jank between frame drops vs. triple buffered

Bug: 70220906
Test: JankyScene vs. systrace vs. jankstats
Change-Id: Ia012685020cc5bcabbd3f92f0bdeb84eaf50733d

libs/hwui/JankTracker.cpp

diff --git a/libs/hwui/JankTracker.cpp b/libs/hwui/JankTracker.cpp
index cf29e43..8110664 100644
--- a/libs/hwui/JankTracker.cpp
+++ b/libs/hwui/JankTracker.cpp
@@ -129,22 +129,42 @@
             totalDuration -= forgiveAmount;
         }
     }
+
     LOG_ALWAYS_FATAL_IF(totalDuration <= 0, "Impossible totalDuration %" PRId64, totalDuration);
     mData->reportFrame(totalDuration);
     (*mGlobalData)->reportFrame(totalDuration);
 
-    // Keep the fast path as fast as possible.
-    if (CC_LIKELY(totalDuration < mFrameInterval)) {
-        return;
-    }
-
     // Only things like Surface.lockHardwareCanvas() are exempt from tracking
-    if (frame[FrameInfoIndex::Flags] & EXEMPT_FRAMES_FLAGS) {
+    if (CC_UNLIKELY(frame[FrameInfoIndex::Flags] & EXEMPT_FRAMES_FLAGS)) {
         return;
     }
 
-    mData->reportJank();
-    (*mGlobalData)->reportJank();
+    if (totalDuration > mFrameInterval) {
+        mData->reportJank();
+        (*mGlobalData)->reportJank();
+    }
+
+    bool isTripleBuffered = mSwapDeadline > frame[FrameInfoIndex::IntendedVsync];
+
+    mSwapDeadline = std::max(mSwapDeadline + mFrameInterval,
+                             frame[FrameInfoIndex::IntendedVsync] + mFrameInterval);
+
+    // If we hit the deadline, cool!
+    if (frame[FrameInfoIndex::FrameCompleted] < mSwapDeadline) {
+        if (isTripleBuffered) {
+            mData->reportJankType(JankType::kHighInputLatency);
+            (*mGlobalData)->reportJankType(JankType::kHighInputLatency);
+        }
+        return;
+    }
+
+    mData->reportJankType(JankType::kMissedDeadline);
+    (*mGlobalData)->reportJankType(JankType::kMissedDeadline);
+
+    // Janked, reset the swap deadline
+    nsecs_t jitterNanos = frame[FrameInfoIndex::FrameCompleted] - frame[FrameInfoIndex::Vsync];
+    nsecs_t lastFrameOffset = jitterNanos % mFrameInterval;
+    mSwapDeadline = frame[FrameInfoIndex::FrameCompleted] - lastFrameOffset + mFrameInterval;
 
     for (int i = 0; i < NUM_BUCKETS; i++) {
         int64_t delta = frame.duration(COMPARISONS[i].start, COMPARISONS[i].end);