commit a8955dd64c0c7fd355a7a3973403c3ba916d6f27
author Dominik Laskowski <domlaskowski@google.com> Wed Jul 10 10:19:09 2019 -0700
committer Dominik Laskowski <domlaskowski@google.com> Fri Jul 26 10:27:49 2019 -0700
tree 6b30a3254d5d63ae0658a6a19c96eebb66510895
parent 654952126842b40699ae0bd8958b2a6eaaeb80d5

SF: Factor out expected present time computation

Compute expected present time once and pass it to traversed layers
instead of calling back into SF for each layer. This will simplify
synchronization for per-display refresh.

Also, recompute on Binder transaction, since the cached value computed
on invalidate may be stale.

Bug: 130554049
Bug: 123715322
Test: go/wm-smoke
Change-Id: I7153a728360e789dc4f97d2c39c4bdaa14183624

services/surfaceflinger/SurfaceFlinger.h

diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 0e6eacf..099ba72 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -295,18 +295,13 @@
 
     // main thread function to enable/disable h/w composer event
     void setPrimaryVsyncEnabledInternal(bool enabled);
+    void setVsyncEnabledInHWC(DisplayId displayId, HWC2::Vsync enabled);
 
     // called on the main thread by MessageQueue when an internal message
     // is received
     // TODO: this should be made accessible only to MessageQueue
     void onMessageReceived(int32_t what);
 
-    // populates the expected present time for this frame.
-    // When we are in negative offsets, we perform a correction so that the
-    // predicted vsync for the *next* frame is used instead.
-    void populateExpectedPresentTime();
-    nsecs_t getExpectedPresentTime() const { return mExpectedPresentTime; }
-
     // for debugging only
     // TODO: this should be made accessible only to HWComposer
     const Vector<sp<Layer>>& getLayerSortedByZForHwcDisplay(DisplayId displayId);
@@ -585,6 +580,7 @@
     void commitOffscreenLayers();
     bool containsAnyInvalidClientState(const Vector<ComposerState>& states);
     bool transactionIsReadyToBeApplied(int64_t desiredPresentTime,
+                                       bool useCachedExpectedPresentTime,
                                        const Vector<ComposerState>& states);
     uint32_t setClientStateLocked(const ComposerState& composerState, int64_t desiredPresentTime,
                                   const std::vector<ListenerCallbacks>& listenerCallbacks,
@@ -816,6 +812,12 @@
 
     bool isDisplayConfigAllowed(int32_t configId) const REQUIRES(mStateLock);
 
+    bool previousFrameMissed();
+
+    // Populates the expected present time for this frame. For negative offsets, performs a
+    // correction using the predicted vsync for the next frame instead.
+    void populateExpectedPresentTime();
+
     /*
      * Display identification
      */
@@ -844,9 +846,6 @@
         return hwcDisplayId ? getHwComposer().toPhysicalDisplayId(*hwcDisplayId) : std::nullopt;
     }
 
-    bool previousFrameMissed();
-    void setVsyncEnabledInHWC(DisplayId displayId, HWC2::Vsync enabled);
-
     /*
      * Debugging & dumpsys
      */
@@ -1135,6 +1134,8 @@
     scheduler::RefreshRateConfigs mRefreshRateConfigs;
     scheduler::RefreshRateStats mRefreshRateStats{mRefreshRateConfigs, *mTimeStats};
 
+    std::atomic<nsecs_t> mExpectedPresentTime = 0;
+
     // All configs are allowed if the set is empty.
     using DisplayConfigs = std::set<int32_t>;
     DisplayConfigs mAllowedDisplayConfigs GUARDED_BY(mStateLock);
@@ -1188,8 +1189,6 @@
     // Flags to capture the state of Vsync in HWC
     HWC2::Vsync mHWCVsyncState = HWC2::Vsync::Disable;
     HWC2::Vsync mHWCVsyncPendingState = HWC2::Vsync::Disable;
-
-    nsecs_t mExpectedPresentTime;
 };
 
 } // namespace android