commit 08222fc6f41627aeb738a566ec0532c3a4f16607
author Prabhanjan Kandula <pkandula@codeaurora.org> Wed Jul 10 17:20:59 2013 +0530
committer Prabhanjan Kandula <pkandula@codeaurora.org> Mon Jul 15 11:21:16 2013 +0530
tree 9414325eb3b6766baaff8006d8e98654878992d3
parent e9efd8a487a66efbedcd2e73c877d43aa5fabf28

hwcomposer: Fix a crash with MDP composition.

Reset the current frame data before returning from MDP
composition prepare to avoid accessing previous frame data
in MDP composition draw phase. Avoid the number of app layers
going beyond the layer count limit in MDP composition.

Change-Id: I2a3035ad5cb1731060b9359ccdbe9fe0c07e843c
CRs-fixed: 510683

libhwcomposer/hwc_mdpcomp.cpp

diff --git a/libhwcomposer/hwc_mdpcomp.cpp b/libhwcomposer/hwc_mdpcomp.cpp
index 2103cb4..22d86a6 100644
--- a/libhwcomposer/hwc_mdpcomp.cpp
+++ b/libhwcomposer/hwc_mdpcomp.cpp
@@ -750,19 +750,20 @@
 
     const int numLayers = ctx->listStats[mDpy].numAppLayers;
 
-    //number of app layers exceeds MAX_NUM_APP_LAYERS fall back to GPU
-    //do not cache the information for next draw cycle.
-    if(numLayers > MAX_NUM_APP_LAYERS) {
-        ALOGD_IF(isDebug(), "%s: Number of App layers exceeded the limit ",
-                 __FUNCTION__);
-        return 0;
-    }
-
     Locker::Autolock _l(mMdpCompLock);
 
     //reset old data
     mCurrentFrame.reset(numLayers);
 
+    //number of app layers exceeds MAX_NUM_APP_LAYERS fall back to GPU
+    //do not cache the information for next draw cycle.
+    if(numLayers > MAX_NUM_APP_LAYERS) {
+        mCachedFrame.updateCounts(mCurrentFrame);
+        ALOGD_IF(isDebug(), "%s: Number of App layers exceeded the limit ",
+                 __FUNCTION__);
+        return 0;
+    }
+
     //Hard conditions, if not met, cannot do MDP comp
     if(!isFrameDoable(ctx)) {
         ALOGD_IF( isDebug(),"%s: MDP Comp not possible for this frame",
@@ -898,6 +899,11 @@
         return false;
     }
 
+    if(ctx->listStats[mDpy].numAppLayers > MAX_NUM_APP_LAYERS) {
+        ALOGD_IF(isDebug(),"%s: Exceeding max layer count", __FUNCTION__);
+        return true;
+    }
+
     Locker::Autolock _l(mMdpCompLock);
 
     /* reset Invalidator */
@@ -948,7 +954,7 @@
         }
 
         if (!ov.queueBuffer(fd, offset, dest)) {
-            ALOGE("%s: queueBuffer failed for external", __FUNCTION__);
+            ALOGE("%s: queueBuffer failed for display:%d ", __FUNCTION__, mDpy);
             return false;
         }
 
@@ -1083,6 +1089,11 @@
         return false;
     }
 
+    if(ctx->listStats[mDpy].numAppLayers > MAX_NUM_APP_LAYERS) {
+        ALOGD_IF(isDebug(),"%s: Exceeding max layer count", __FUNCTION__);
+        return true;
+    }
+
     Locker::Autolock _l(mMdpCompLock);
 
     /* reset Invalidator */