commit 2d5e230292c27d59f4c096bc742a0a19abf811c1
author Jamie Gennis <jgennis@google.com> Mon Oct 15 18:24:43 2012 -0700
committer Jamie Gennis <jgennis@google.com> Mon Oct 15 19:09:04 2012 -0700
tree b8017bb03c4eb1907757de6352059ff84e33646f
parent 9bdaa60b809b223d14619d1f13afdd38acb1738d

SurfaceFlinger: add animation transactions

This change adds a transaction flag for WindowManager to indicate that a
transaction is being used to animate windows around the screen.  SurfaceFlinger
will not allow more than one of these transactions to be outstanding at a time
to prevent the animation "frames" from being dropped.

Bug: 7353840
Change-Id: I6488a6e0e1ed13d27356d2203c9dc766dc6b1759

services/surfaceflinger/SurfaceFlinger.cpp

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 492d1cf..e21e2bf 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -86,7 +86,8 @@
 SurfaceFlinger::SurfaceFlinger()
     :   BnSurfaceComposer(), Thread(false),
         mTransactionFlags(0),
-        mTransationPending(false),
+        mTransactionPending(false),
+        mAnimTransactionPending(false),
         mLayersRemoved(false),
         mRepaintEverything(0),
         mBootTime(systemTime()),
@@ -1264,7 +1265,8 @@
     }
 
     mDrawingState = mCurrentState;
-    mTransationPending = false;
+    mTransactionPending = false;
+    mAnimTransactionPending = false;
     mTransactionCV.broadcast();
 }
 
@@ -1665,6 +1667,21 @@
     Mutex::Autolock _l(mStateLock);
     uint32_t transactionFlags = 0;
 
+    if (flags & eAnimation) {
+        // For window updates that are part of an animation we must wait for
+        // previous animation "frames" to be handled.
+        while (mAnimTransactionPending) {
+            status_t err = mTransactionCV.waitRelative(mStateLock, 500 * 1000);
+            if (CC_UNLIKELY(err != NO_ERROR)) {
+                // just in case something goes wrong in SF, return to the
+                // caller after a few hundred microseconds.
+                ALOGW_IF(err == TIMED_OUT, "setTransactionState timed out!");
+                mAnimTransactionPending = false;
+                break;
+            }
+        }
+    }
+
     size_t count = displays.size();
     for (size_t i=0 ; i<count ; i++) {
         const DisplayState& s(displays[i]);
@@ -1685,15 +1702,18 @@
         // if this is a synchronous transaction, wait for it to take effect
         // before returning.
         if (flags & eSynchronous) {
-            mTransationPending = true;
+            mTransactionPending = true;
         }
-        while (mTransationPending) {
+        if (flags & eAnimation) {
+            mAnimTransactionPending = true;
+        }
+        while (mTransactionPending) {
             status_t err = mTransactionCV.waitRelative(mStateLock, s2ns(5));
             if (CC_UNLIKELY(err != NO_ERROR)) {
                 // just in case something goes wrong in SF, return to the
                 // called after a few seconds.
-                ALOGW_IF(err == TIMED_OUT, "closeGlobalTransaction timed out!");
-                mTransationPending = false;
+                ALOGW_IF(err == TIMED_OUT, "setTransactionState timed out!");
+                mTransactionPending = false;
                 break;
             }
         }

services/surfaceflinger/SurfaceFlinger.h

diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 6d36719..efe34af 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -398,7 +398,8 @@
     volatile int32_t mTransactionFlags;
     Condition mTransactionCV;
     SortedVector<sp<LayerBase> > mLayerPurgatory;
-    bool mTransationPending;
+    bool mTransactionPending;
+    bool mAnimTransactionPending;
     Vector<sp<LayerBase> > mLayersPendingRemoval;
 
     // protected by mStateLock (but we could use another lock)