commit 16c112df109e81e392eb1f337cba2fe2fdf6d42e
author Marissa Wall <marissaw@google.com> Wed Mar 20 13:21:13 2019 -0700
committer Marissa Wall <marissaw@google.com> Fri Mar 22 16:24:08 2019 +0000
tree bf7361690bb55a585e13b1f82d87f3d5b205b4ad
parent 4c6f904ffde2795886477f6de54edcae5d036e68

blast: fix 30Hz wake up issue

When playing 30Hz video, SurfaceFlinger was waking up at a rate of
60Hz. This is because hasFrameUpdate returned true after the update
was already applied. mCurrentStateModified was being cleared after
the frame was sent to HWC instead of when the buffer was latched.

By moving "mCurrentStateModified = false" to latch, the hasFrameUpdate
returns false so SurfaceFlinger doesn't schedule the extra wake up.

Test: SurfaceFlinger_test
Bug: 128520233

Change-Id: I2f18c6d03b81affb1235d6b466d665e711b1db8c

services/surfaceflinger/BufferStateLayer.cpp

diff --git a/services/surfaceflinger/BufferStateLayer.cpp b/services/surfaceflinger/BufferStateLayer.cpp
index 1ca0b02..0fc7333 100644
--- a/services/surfaceflinger/BufferStateLayer.cpp
+++ b/services/surfaceflinger/BufferStateLayer.cpp
@@ -551,6 +551,8 @@
     mFlinger->mTimeStats->setAcquireFence(layerID, getFrameNumber(), getCurrentFenceTime());
     mFlinger->mTimeStats->setLatchTime(layerID, getFrameNumber(), latchTime);
 
+    mCurrentStateModified = false;
+
     return NO_ERROR;
 }
 
@@ -600,7 +602,6 @@
               s.buffer->handle, to_string(error).c_str(), static_cast<int32_t>(error));
     }
 
-    mCurrentStateModified = false;
     mFrameNumber++;
 }