commit 1eba0209b82676a02288843a4776b709eb57e8fa
author Dominik Laskowski <domlaskowski@google.com> Thu Jan 24 09:14:40 2019 -0800
committer Dominik Laskowski <domlaskowski@google.com> Mon Jan 28 11:30:56 2019 -0800
tree da96bbc3c2277dde380635570a473cbda9ce4dc6
parent 029cc12ba5834559839da900ee999754e6ca1dd6

SF: Tie VSyncState lifetime to display hotplug

This CL creates/destroys EventThread::VSyncState when the display is
connected/disconnected.

Bug: 74619554
Test: libsurfaceflinger_unittest
Test: dumpsys SurfaceFlinger --vsync
Change-Id: I46dad4857222b6d2932ab568c4d66325edc3371b

services/surfaceflinger/Scheduler/EventThread.h

diff --git a/services/surfaceflinger/Scheduler/EventThread.h b/services/surfaceflinger/Scheduler/EventThread.h
index f093e47..89b799e 100644
--- a/services/surfaceflinger/Scheduler/EventThread.h
+++ b/services/surfaceflinger/Scheduler/EventThread.h
@@ -22,6 +22,7 @@
 #include <cstdint>
 #include <deque>
 #include <mutex>
+#include <optional>
 #include <thread>
 #include <vector>
 
@@ -198,7 +199,9 @@
 
     // VSYNC state of connected display.
     struct VSyncState {
-        uint32_t displayId = 0;
+        explicit VSyncState(uint32_t displayId) : displayId(displayId) {}
+
+        const uint32_t displayId;
 
         // Number of VSYNC events since display was connected.
         uint32_t count = 0;
@@ -207,7 +210,9 @@
         bool synthetic = false;
     };
 
-    VSyncState mVSyncState GUARDED_BY(mMutex);
+    // TODO(b/74619554): Create per-display threads waiting on respective VSYNC signals,
+    // and support headless mode by injecting a fake display with synthetic VSYNC.
+    std::optional<VSyncState> mVSyncState GUARDED_BY(mMutex);
 
     // State machine for event loop.
     enum class State {