commit c53f121969cea48d8ac64162b201ca5389959d83
author Alec Mouri <alecmouri@google.com> Wed Nov 10 00:52:35 2021 +0000
committer Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com> Wed Nov 10 00:52:35 2021 +0000
tree 21f6c6d094206ca477e11b3c6eb829efea539c37
parent 9f9879f5dd7b19760c468da976a4925a9341bfbb
parent 8816376a1158752e8970eb95af68de80c12038a0

Merge "Dispatch vsync when receiving vsync timeout to handle vsync loss." am: 8816376a11

Original change: https://android-review.googlesource.com/c/platform/frameworks/native/+/1867826

Change-Id: I55bf750706b5cf80e1a0d7de1af6a6ae6d174aef

libs/gui/DisplayEventDispatcher.cpp

diff --git a/libs/gui/DisplayEventDispatcher.cpp b/libs/gui/DisplayEventDispatcher.cpp
index e1b1efc..46800f2 100644
--- a/libs/gui/DisplayEventDispatcher.cpp
+++ b/libs/gui/DisplayEventDispatcher.cpp
@@ -33,10 +33,13 @@
 // using just a few large reads.
 static const size_t EVENT_BUFFER_SIZE = 100;
 
+static constexpr nsecs_t WAITING_FOR_VSYNC_TIMEOUT = ms2ns(300);
+
 DisplayEventDispatcher::DisplayEventDispatcher(
         const sp<Looper>& looper, ISurfaceComposer::VsyncSource vsyncSource,
         ISurfaceComposer::EventRegistrationFlags eventRegistration)
-      : mLooper(looper), mReceiver(vsyncSource, eventRegistration), mWaitingForVsync(false) {
+      : mLooper(looper), mReceiver(vsyncSource, eventRegistration), mWaitingForVsync(false),
+        mLastVsyncCount(0), mLastScheduleVsyncTime(0) {
     ALOGV("dispatcher %p ~ Initializing display event dispatcher.", this);
 }
 
@@ -86,6 +89,7 @@
         }
 
         mWaitingForVsync = true;
+        mLastScheduleVsyncTime = systemTime(SYSTEM_TIME_MONOTONIC);
     }
     return OK;
 }
@@ -124,9 +128,21 @@
               this, ns2ms(vsyncTimestamp), to_string(vsyncDisplayId).c_str(), vsyncCount,
               vsyncEventData.id);
         mWaitingForVsync = false;
+        mLastVsyncCount = vsyncCount;
         dispatchVsync(vsyncTimestamp, vsyncDisplayId, vsyncCount, vsyncEventData);
     }
 
+    if (mWaitingForVsync) {
+        const nsecs_t currentTime = systemTime(SYSTEM_TIME_MONOTONIC);
+        const nsecs_t vsyncScheduleDelay = currentTime - mLastScheduleVsyncTime;
+        if (vsyncScheduleDelay > WAITING_FOR_VSYNC_TIMEOUT) {
+            ALOGW("Vsync time out! vsyncScheduleDelay=%" PRId64 "ms", ns2ms(vsyncScheduleDelay));
+            mWaitingForVsync = false;
+            dispatchVsync(currentTime, vsyncDisplayId /* displayId is not used */,
+                          ++mLastVsyncCount, vsyncEventData /* empty data */);
+        }
+    }
+
     return 1; // keep the callback
 }
 

libs/gui/include/gui/DisplayEventDispatcher.h

diff --git a/libs/gui/include/gui/DisplayEventDispatcher.h b/libs/gui/include/gui/DisplayEventDispatcher.h
index 4ade240..08f3597 100644
--- a/libs/gui/include/gui/DisplayEventDispatcher.h
+++ b/libs/gui/include/gui/DisplayEventDispatcher.h
@@ -56,6 +56,8 @@
     sp<Looper> mLooper;
     DisplayEventReceiver mReceiver;
     bool mWaitingForVsync;
+    uint32_t mLastVsyncCount;
+    nsecs_t mLastScheduleVsyncTime;
 
     std::vector<FrameRateOverride> mFrameRateOverrides;