commit f3441822fb8360cacd2d30bcb6731c2841597fc9
author Huihong Luo <huisinro@google.com> Wed Jun 16 15:41:07 2021 -0700
committer Huihong Luo <huisinro@google.com> Mon Jun 28 21:24:33 2021 +0000
tree 66a638e39d8c5dad43eaf9805fb346fdbfa43539
parent 75fe7e540bf80a76c48b2f73d9a0aafc0b177458

Re-introduce debug.sf.latch_unsignaled

This pretty much reverts this commit: Ia453eaf895554adbb2fa9c11c2bc8609e1037ea5.
Some devices may find this helpful to improve performance, but there is a risk of pipeline stall from misbehaving apps.

Bug: 173694115
Test: manual
Change-Id: I48c3095061dc106fa08d36b8ef17eccb04fb6eb1

services/surfaceflinger/BufferStateLayer.cpp

diff --git a/services/surfaceflinger/BufferStateLayer.cpp b/services/surfaceflinger/BufferStateLayer.cpp
index 2a49a0a..645e883 100644
--- a/services/surfaceflinger/BufferStateLayer.cpp
+++ b/services/surfaceflinger/BufferStateLayer.cpp
@@ -635,6 +635,10 @@
 // Interface implementation for BufferLayer
 // -----------------------------------------------------------------------
 bool BufferStateLayer::fenceHasSignaled() const {
+    if (SurfaceFlinger::enableLatchUnsignaled) {
+        return true;
+    }
+
     const bool fenceSignaled =
             getDrawingState().acquireFence->getStatus() == Fence::Status::Signaled;
     if (!fenceSignaled) {