commit 7f01518eae5ce54d1b4bfc682c1c7b68bac89cb5
author Alec Mouri <alecmouri@google.com> Thu Jul 11 13:56:22 2019 -0700
committer Alec Mouri <alecmouri@google.com> Mon Jul 15 12:02:36 2019 -0700
tree fc39b77f4ec257765718654f822d82e89b9d4b4a
parent 11b359d023022b8078067cc3be7c22f95fe02234

[SurfaceFlinger] Don't touch hw vsync in DEFAULT RR with kernel timeout

As a power optimization, hw vsync shouldn't be enabled when the kernel
timer resets if the display is going to run at 60hz anyways.

Bug: 136197211
Test: systrace when scrolling at peak refresh rate of 60hz.
Change-Id: Ic7df3e7b735f79b183cdd91f770de83082e491b4

services/surfaceflinger/Scheduler/Scheduler.cpp

diff --git a/services/surfaceflinger/Scheduler/Scheduler.cpp b/services/surfaceflinger/Scheduler/Scheduler.cpp
index cfdbd91..d2270d3 100644
--- a/services/surfaceflinger/Scheduler/Scheduler.cpp
+++ b/services/surfaceflinger/Scheduler/Scheduler.cpp
@@ -380,11 +380,17 @@
 }
 
 void Scheduler::setChangeRefreshRateCallback(
-        const ChangeRefreshRateCallback& changeRefreshRateCallback) {
+        const ChangeRefreshRateCallback&& changeRefreshRateCallback) {
     std::lock_guard<std::mutex> lock(mCallbackLock);
     mChangeRefreshRateCallback = changeRefreshRateCallback;
 }
 
+void Scheduler::setGetCurrentRefreshRateTypeCallback(
+        const GetCurrentRefreshRateTypeCallback&& getCurrentRefreshRateTypeCallback) {
+    std::lock_guard<std::mutex> lock(mCallbackLock);
+    mGetCurrentRefreshRateTypeCallback = getCurrentRefreshRateTypeCallback;
+}
+
 void Scheduler::setGetVsyncPeriodCallback(const GetVsyncPeriod&& getVsyncPeriod) {
     std::lock_guard<std::mutex> lock(mCallbackLock);
     mGetVsyncPeriod = getVsyncPeriod;
@@ -427,8 +433,13 @@
 void Scheduler::resetKernelTimerCallback() {
     ATRACE_INT("ExpiredKernelIdleTimer", 0);
     std::lock_guard<std::mutex> lock(mCallbackLock);
-    if (mGetVsyncPeriod) {
-        resyncToHardwareVsync(true, mGetVsyncPeriod());
+    if (mGetVsyncPeriod && mGetCurrentRefreshRateTypeCallback) {
+        // If we're not in performance mode then the kernel timer shouldn't do
+        // anything, as the refresh rate during DPU power collapse will be the
+        // same.
+        if (mGetCurrentRefreshRateTypeCallback() == Scheduler::RefreshRateType::PERFORMANCE) {
+            resyncToHardwareVsync(true, mGetVsyncPeriod());
+        }
     }
 }
 
@@ -450,10 +461,16 @@
 }
 
 void Scheduler::expiredKernelTimerCallback() {
+    std::lock_guard<std::mutex> lock(mCallbackLock);
     ATRACE_INT("ExpiredKernelIdleTimer", 1);
-    // Disable HW Vsync if the timer expired, as we don't need it
-    // enabled if we're not pushing frames.
-    disableHardwareVsync(false);
+    if (mGetCurrentRefreshRateTypeCallback) {
+        if (mGetCurrentRefreshRateTypeCallback() != Scheduler::RefreshRateType::PERFORMANCE) {
+            // Disable HW Vsync if the timer expired, as we don't need it
+            // enabled if we're not pushing frames, and if we're in PERFORMANCE
+            // mode then we'll need to re-update the DispSync model anyways.
+            disableHardwareVsync(false);
+        }
+    }
 }
 
 std::string Scheduler::doDump() {