commit cd9b55c70f081dbd004d347b51a793ce6fe3cacf
author Matthew Bouyack <mbouyack@google.com> Thu Jun 01 14:37:29 2017 -0700
committer Matthew Bouyack <mbouyack@google.com> Wed Jun 07 16:24:17 2017 -0700
tree 4e7485e4eb0eb8c3d37ea9cce7e0bd9ff894dcd5
parent 177759a90584489b1b77cdaf3818ebdb79b1b9bf

Eliminate redundant changes to hardware vsync state.

When transitioning between NORMAL and DOZE power modes
we were redundantly calling resyncHardwareVsync.

Similarly, when transitioning from DOZE_SUSPEND to OFF
we were redundantly calling disableHardwareVsync.

This change eliminates those redundant calls.

Fixes bug 62235417

Change-Id: I513bbf94a7ab973ab258efe16436441ac2379b70

services/surfaceflinger/SurfaceFlinger.cpp

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 7392006..ee63ebc 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -3210,7 +3210,8 @@
             ALOGW("Couldn't set SCHED_OTHER on display off");
         }
 
-        if (type == DisplayDevice::DISPLAY_PRIMARY) {
+        if (type == DisplayDevice::DISPLAY_PRIMARY &&
+            currentMode != HWC_POWER_MODE_DOZE_SUSPEND) {
             disableHardwareVsync(true); // also cancels any in-progress resync
 
             // FIXME: eventthread only knows about the main display right now
@@ -3224,7 +3225,8 @@
                mode == HWC_POWER_MODE_NORMAL) {
         // Update display while dozing
         getHwComposer().setPowerMode(type, mode);
-        if (type == DisplayDevice::DISPLAY_PRIMARY) {
+        if (type == DisplayDevice::DISPLAY_PRIMARY &&
+            currentMode == HWC_POWER_MODE_DOZE_SUSPEND) {
             // FIXME: eventthread only knows about the main display right now
             mEventThread->onScreenAcquired();
             resyncToHardwareVsync(true);