commit 42b918ef9d67d655d3f1c04f72354fc5eec34d95
author Vishnu Nair <vishnun@google.com> Tue Jul 18 20:05:29 2023 +0000
committer Vishnu Nair <vishnun@google.com> Tue Jul 18 20:05:29 2023 +0000
tree 32094ecc62c82ef96ebecb96cbeeb8d2dbe939c5
parent d2bfbb3276003e6a5d8eb4dddab633eff4d4e346

[sf] Update framerate correctly with new frontend

In order to optimize snapshot updates, we only
update the snapshot if the requested state has changed.
If the hierarchy changes, we force update the children's
snapshot but this is not sufficient because a parent's
framerate might be affect by the child's framerate.

To fix this explicitly update the framerate when the
hierarchy changes.

Test: presubmit
Test: atest android.graphics.cts.FrameRateOverrideTest
Bug: 238781169
Change-Id: Ia633e7800cf3169c944313b4220b889bec0c3c5f

services/surfaceflinger/FrontEnd/LayerSnapshotBuilder.cpp

diff --git a/services/surfaceflinger/FrontEnd/LayerSnapshotBuilder.cpp b/services/surfaceflinger/FrontEnd/LayerSnapshotBuilder.cpp
index 3a19d0b..7e678b9 100644
--- a/services/surfaceflinger/FrontEnd/LayerSnapshotBuilder.cpp
+++ b/services/surfaceflinger/FrontEnd/LayerSnapshotBuilder.cpp
@@ -558,7 +558,7 @@
         const LayerSnapshot& childSnapshot =
                 updateSnapshotsInHierarchy(args, *childHierarchy, traversalPath, *snapshot,
                                            depth + 1);
-        updateChildState(*snapshot, childSnapshot, args);
+        updateFrameRateFromChildSnapshot(*snapshot, childSnapshot, args);
     }
 
     if (oldFrameRate == snapshot->frameRate) {
@@ -666,36 +666,40 @@
     }
 }
 
-void LayerSnapshotBuilder::updateChildState(LayerSnapshot& snapshot,
-                                            const LayerSnapshot& childSnapshot, const Args& args) {
-    if (snapshot.childState.hasValidFrameRate) {
+void LayerSnapshotBuilder::updateFrameRateFromChildSnapshot(LayerSnapshot& snapshot,
+                                                            const LayerSnapshot& childSnapshot,
+                                                            const Args& args) {
+    if (args.forceUpdate == ForceUpdateFlags::NONE &&
+        !childSnapshot.changes.any(RequestedLayerState::Changes::FrameRate |
+                                   RequestedLayerState::Changes::Hierarchy)) {
         return;
     }
-    if (args.forceUpdate == ForceUpdateFlags::ALL ||
-        childSnapshot.changes.test(RequestedLayerState::Changes::FrameRate)) {
-        // We return whether this layer ot its children has a vote. We ignore ExactOrMultiple votes
-        // for the same reason we are allowing touch boost for those layers. See
-        // RefreshRateSelector::rankFrameRates for details.
-        using FrameRateCompatibility = scheduler::LayerInfo::FrameRateCompatibility;
-        const auto layerVotedWithDefaultCompatibility = childSnapshot.frameRate.rate.isValid() &&
-                childSnapshot.frameRate.type == FrameRateCompatibility::Default;
-        const auto layerVotedWithNoVote =
-                childSnapshot.frameRate.type == FrameRateCompatibility::NoVote;
-        const auto layerVotedWithExactCompatibility = childSnapshot.frameRate.rate.isValid() &&
-                childSnapshot.frameRate.type == FrameRateCompatibility::Exact;
 
-        snapshot.childState.hasValidFrameRate |= layerVotedWithDefaultCompatibility ||
-                layerVotedWithNoVote || layerVotedWithExactCompatibility;
+    using FrameRateCompatibility = scheduler::LayerInfo::FrameRateCompatibility;
+    if (snapshot.frameRate.rate.isValid() ||
+        snapshot.frameRate.type == FrameRateCompatibility::NoVote) {
+        // we already have a valid framerate.
+        return;
+    }
 
-        // If we don't have a valid frame rate, but the children do, we set this
-        // layer as NoVote to allow the children to control the refresh rate
-        if (!snapshot.frameRate.rate.isValid() &&
-            snapshot.frameRate.type != FrameRateCompatibility::NoVote &&
-            snapshot.childState.hasValidFrameRate) {
-            snapshot.frameRate =
-                    scheduler::LayerInfo::FrameRate(Fps(), FrameRateCompatibility::NoVote);
-            snapshot.changes |= childSnapshot.changes & RequestedLayerState::Changes::FrameRate;
-        }
+    // We return whether this layer or its children has a vote. We ignore ExactOrMultiple votes
+    // for the same reason we are allowing touch boost for those layers. See
+    // RefreshRateSelector::rankFrameRates for details.
+    const auto layerVotedWithDefaultCompatibility = childSnapshot.frameRate.rate.isValid() &&
+            childSnapshot.frameRate.type == FrameRateCompatibility::Default;
+    const auto layerVotedWithNoVote =
+            childSnapshot.frameRate.type == FrameRateCompatibility::NoVote;
+    const auto layerVotedWithExactCompatibility = childSnapshot.frameRate.rate.isValid() &&
+            childSnapshot.frameRate.type == FrameRateCompatibility::Exact;
+
+    bool childHasValidFrameRate = layerVotedWithDefaultCompatibility || layerVotedWithNoVote ||
+            layerVotedWithExactCompatibility;
+
+    // If we don't have a valid frame rate, but the children do, we set this
+    // layer as NoVote to allow the children to control the refresh rate
+    if (childHasValidFrameRate) {
+        snapshot.frameRate = scheduler::LayerInfo::FrameRate(Fps(), FrameRateCompatibility::NoVote);
+        snapshot.changes |= RequestedLayerState::Changes::FrameRate;
     }
 }
 
@@ -812,7 +816,9 @@
         }
     }
 
-    if (forceUpdate || snapshot.changes.any(RequestedLayerState::Changes::FrameRate)) {
+    if (forceUpdate ||
+        snapshot.changes.any(RequestedLayerState::Changes::FrameRate |
+                             RequestedLayerState::Changes::Hierarchy)) {
         snapshot.frameRate = (requested.requestedFrameRate.rate.isValid() ||
                               (requested.requestedFrameRate.type ==
                                scheduler::LayerInfo::FrameRateCompatibility::NoVote))