SF - plumbing game mode for metrics (Part 1)

This change adds a game mode in the Layer metadata that gets updated every
time a game app comes to the foreground. The gameMode is then set on the
Layer based on the metadata and reparenting.

The game mode will then be
updated in TimeStats as a dimension (Part 2, in a separate CL later).

Bug: 186025682
Test: libsurfaceflinger_unittest:GameModeTest

Change-Id: I09deffc01d1b318cc08d0475611289dec055c190

1 files changed, 7 insertions, 0 deletions

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 881ee5b8f4..3f75af2908 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -4018,6 +4018,13 @@ uint32_t SurfaceFlinger::setClientStateLocked(
     std::optional<nsecs_t> dequeueBufferTimestamp;
     if (what & layer_state_t::eMetadataChanged) {
         dequeueBufferTimestamp = s.metadata.getInt64(METADATA_DEQUEUE_TIME);
+        auto gameMode = s.metadata.getInt32(METADATA_GAME_MODE, -1);
+        if (gameMode != -1) {
+            // The transaction will be received on the Task layer and needs to be applied to all
+            // child layers. Child layers that are added at a later point will obtain the game mode
+            // info through addChild().
+            layer->setGameModeForTree(gameMode);
+        }
         if (layer->setMetadata(s.metadata)) flags |= eTraversalNeeded;
     }
     if (what & layer_state_t::eColorSpaceAgnosticChanged) {