commit 81cd5d3b94d21253a0be925f4ae58cc7f4afeef7
author Mathias Agopian <mathias@google.com> Thu Oct 04 02:34:38 2012 -0700
committer Android (Google) Code Review <android-gerrit@google.com> Thu Oct 04 15:25:32 2012 -0700
tree decaf197dbbf88bf64a2547a241ec6df19a2bfe5
parent 27ec5739bc05330e08b02f25b62a8f597bad897a

make sure we don't call into the HWC HAL when not needed

when enabling/disabling vsync we now make sure to
not call into the HAL if the state wouldn't change.

Bug: 7274951

Change-Id: Ie24a6d68888a51b577acf9c2a973d85437cbacaf

services/surfaceflinger/DisplayHardware/HWComposer.h

diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.h b/services/surfaceflinger/DisplayHardware/HWComposer.h
index af33999..269e147 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.h
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.h
@@ -92,10 +92,10 @@
     status_t commit();
 
     // release hardware resources and blank screen
-    status_t release(int disp) const;
+    status_t release(int disp);
 
     // acquire hardware resources and unblank screen
-    status_t acquire(int disp) const;
+    status_t acquire(int disp);
 
     // reset state when an external, non-virtual display is disconnected
     void disconnectDisplay(int disp);
@@ -226,7 +226,7 @@
         EVENT_VSYNC = HWC_EVENT_VSYNC
     };
 
-    void eventControl(int event, int enabled);
+    void eventControl(int disp, int event, int enabled);
 
     // Query display parameters.  Pass in a display index (e.g.
     // HWC_DISPLAY_PRIMARY).
@@ -289,7 +289,7 @@
         DisplayData() : xdpi(0), ydpi(0), refresh(0),
             connected(false), hasFbComp(false), hasOvComp(false),
             capacity(0), list(NULL),
-            framebufferTarget(NULL), fbTargetHandle(NULL) { }
+            framebufferTarget(NULL), fbTargetHandle(NULL), events(0) { }
         ~DisplayData() {
             free(list);
         }
@@ -306,6 +306,8 @@
         hwc_display_contents_1* list;
         hwc_layer_1* framebufferTarget;
         buffer_handle_t fbTargetHandle;
+        // protected by mEventControlLock
+        int32_t events;
     };
 
     sp<SurfaceFlinger>              mFlinger;
@@ -327,6 +329,9 @@
     // protected by mLock
     mutable Mutex mLock;
     mutable nsecs_t mLastHwVSync;
+
+    // thread-safe
+    mutable Mutex mEventControlLock;
 };
 
 // ---------------------------------------------------------------------------