SurfaceFlinger: make sync transactions explicit

This change enables a layer or orientation update transaction sent to
SurfaceFlinger to explicitly request a synchronous transaction.

Change-Id: I97cbba610c13679849f66114b216fa6dbf12f2a9

6 files changed, 53 insertions, 31 deletions

diff --git a/include/surfaceflinger/ISurfaceComposer.h b/include/surfaceflinger/ISurfaceComposer.h
index ea022a6..26cf094 100644
--- a/include/surfaceflinger/ISurfaceComposer.h
+++ b/include/surfaceflinger/ISurfaceComposer.h
@@ -83,7 +83,11 @@ public:
         eOrientationUnchanged   = 4,
         eOrientationSwapMask    = 0x01
     };
-    
+
+    enum {
+        eSynchronous            = 0x01,
+    };
+
     enum {
         eElectronBeamAnimationOn  = 0x01,
         eElectronBeamAnimationOff = 0x10
@@ -103,7 +107,7 @@ public:
 
     /* open/close transactions. requires ACCESS_SURFACE_FLINGER permission */
     virtual void setTransactionState(const Vector<ComposerState>& state,
-            int orientation) = 0;
+            int orientation, uint32_t flags) = 0;
 
     /* signal that we're done booting.
      * Requires ACCESS_SURFACE_FLINGER permission
diff --git a/include/surfaceflinger/SurfaceComposerClient.h b/include/surfaceflinger/SurfaceComposerClient.h
index 14e5b23..8226abe 100644
--- a/include/surfaceflinger/SurfaceComposerClient.h
+++ b/include/surfaceflinger/SurfaceComposerClient.h
@@ -112,7 +112,7 @@ public:
     static void openGlobalTransaction();
         
     //! Close a composer transaction on all active SurfaceComposerClients.
-    static void closeGlobalTransaction();
+    static void closeGlobalTransaction(bool synchronous = false);
     
     //! Freeze the specified display but not transactions.
     static status_t freezeDisplay(DisplayID dpy, uint32_t flags = 0);
diff --git a/libs/gui/ISurfaceComposer.cpp b/libs/gui/ISurfaceComposer.cpp
index eb90147..86bc62a 100644
--- a/libs/gui/ISurfaceComposer.cpp
+++ b/libs/gui/ISurfaceComposer.cpp
@@ -79,7 +79,7 @@ public:
     }
 
     virtual void setTransactionState(const Vector<ComposerState>& state,
-            int orientation)
+            int orientation, uint32_t flags)
     {
         Parcel data, reply;
         data.writeInterfaceToken(ISurfaceComposer::getInterfaceDescriptor());
@@ -90,6 +90,7 @@ public:
             b->write(data);
         }
         data.writeInt32(orientation);
+        data.writeInt32(flags);
         remote()->transact(BnSurfaceComposer::SET_TRANSACTION_STATE, data, &reply);
     }
 
@@ -204,7 +205,8 @@ status_t BnSurfaceComposer::onTransact(
                 state.add(s);
             }
             int orientation = data.readInt32();
-            setTransactionState(state, orientation);
+            uint32_t flags = data.readInt32();
+            setTransactionState(state, orientation, flags);
         } break;
         case BOOT_FINISHED: {
             CHECK_INTERFACE(ISurfaceComposer, data, reply);
diff --git a/libs/gui/SurfaceComposerClient.cpp b/libs/gui/SurfaceComposerClient.cpp
index 5f3d608..4ad6c22 100644
--- a/libs/gui/SurfaceComposerClient.cpp
+++ b/libs/gui/SurfaceComposerClient.cpp
@@ -92,11 +92,14 @@ class Composer : public Singleton<Composer>
     mutable Mutex               mLock;
     SortedVector<ComposerState> mStates;
     int                         mOrientation;
+    uint32_t                    mForceSynchronous;
 
     Composer() : Singleton<Composer>(),
-        mOrientation(ISurfaceComposer::eOrientationUnchanged) { }
+        mOrientation(ISurfaceComposer::eOrientationUnchanged),
+        mForceSynchronous(0)
+    { }
 
-    void closeGlobalTransactionImpl();
+    void closeGlobalTransactionImpl(bool synchronous);
 
     layer_state_t* getLayerStateLocked(
             const sp<SurfaceComposerClient>& client, SurfaceID id);
@@ -123,8 +126,8 @@ public:
             uint32_t tint);
     status_t setOrientation(int orientation);
 
-    static void closeGlobalTransaction() {
-        Composer::getInstance().closeGlobalTransactionImpl();
+    static void closeGlobalTransaction(bool synchronous) {
+        Composer::getInstance().closeGlobalTransactionImpl(synchronous);
     }
 };
 
@@ -132,11 +135,12 @@ ANDROID_SINGLETON_STATIC_INSTANCE(Composer);
 
 // ---------------------------------------------------------------------------
 
-void Composer::closeGlobalTransactionImpl() {
+void Composer::closeGlobalTransactionImpl(bool synchronous) {
     sp<ISurfaceComposer> sm(getComposerService());
 
     Vector<ComposerState> transaction;
     int orientation;
+    uint32_t flags = 0;
 
     { // scope for the lock
         Mutex::Autolock _l(mLock);
@@ -145,9 +149,14 @@ void Composer::closeGlobalTransactionImpl() {
 
         orientation = mOrientation;
         mOrientation = ISurfaceComposer::eOrientationUnchanged;
+
+        if (synchronous || mForceSynchronous) {
+            flags |= ISurfaceComposer::eSynchronous;
+        }
+        mForceSynchronous = false;
     }
 
-   sm->setTransactionState(transaction, orientation);
+   sm->setTransactionState(transaction, orientation, flags);
 }
 
 layer_state_t* Composer::getLayerStateLocked(
@@ -188,6 +197,10 @@ status_t Composer::setSize(const sp<SurfaceComposerClient>& client,
     s->what |= ISurfaceComposer::eSizeChanged;
     s->w = w;
     s->h = h;
+
+    // Resizing a surface makes the transaction synchronous.
+    mForceSynchronous = true;
+
     return NO_ERROR;
 }
 
@@ -270,6 +283,10 @@ status_t Composer::setFreezeTint(const sp<SurfaceComposerClient>& client,
 status_t Composer::setOrientation(int orientation) {
     Mutex::Autolock _l(mLock);
     mOrientation = orientation;
+
+    // Changing the orientation makes the transaction synchronous.
+    mForceSynchronous = true;
+
     return NO_ERROR;
 }
 
@@ -375,8 +392,8 @@ void SurfaceComposerClient::openGlobalTransaction() {
     // Currently a no-op
 }
 
-void SurfaceComposerClient::closeGlobalTransaction() {
-    Composer::closeGlobalTransaction();
+void SurfaceComposerClient::closeGlobalTransaction(bool synchronous) {
+    Composer::closeGlobalTransaction(synchronous);
 }
 
 // ----------------------------------------------------------------------------
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 1441a54..bfb5cf4 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -79,7 +79,7 @@ const String16 sDump("android.permission.DUMP");
 SurfaceFlinger::SurfaceFlinger()
     :   BnSurfaceComposer(), Thread(false),
         mTransactionFlags(0),
-        mResizeTransationPending(false),
+        mTransationPending(false),
         mLayersRemoved(false),
         mBootTime(systemTime()),
         mVisibleRegionsDirty(false),
@@ -748,7 +748,7 @@ void SurfaceFlinger::computeVisibleRegions(
 void SurfaceFlinger::commitTransaction()
 {
     mDrawingState = mCurrentState;
-    mResizeTransationPending = false;
+    mTransationPending = false;
     mTransactionCV.broadcast();
 }
 
@@ -1235,15 +1235,14 @@ uint32_t SurfaceFlinger::setTransactionFlags(uint32_t flags)
 
 
 void SurfaceFlinger::setTransactionState(const Vector<ComposerState>& state,
-        int orientation) {
+        int orientation, uint32_t flags) {
     Mutex::Autolock _l(mStateLock);
 
-    uint32_t flags = 0;
+    uint32_t transactionFlags = 0;
     if (mCurrentState.orientation != orientation) {
         if (uint32_t(orientation)<=eOrientation270 || orientation==42) {
             mCurrentState.orientation = orientation;
-            flags |= eTransactionNeeded;
-            mResizeTransationPending = true;
+            transactionFlags |= eTransactionNeeded;
         } else if (orientation != eOrientationUnchanged) {
             LOGW("setTransactionState: ignoring unrecognized orientation: %d",
                     orientation);
@@ -1254,23 +1253,24 @@ void SurfaceFlinger::setTransactionState(const Vector<ComposerState>& state,
     for (size_t i=0 ; i<count ; i++) {
         const ComposerState& s(state[i]);
         sp<Client> client( static_cast<Client *>(s.client.get()) );
-        flags |= setClientStateLocked(client, s.state);
+        transactionFlags |= setClientStateLocked(client, s.state);
     }
-    if (flags) {
-        setTransactionFlags(flags);
+    if (transactionFlags) {
+        setTransactionFlags(transactionFlags);
     }
 
-    signalEvent();
-
-    // if there is a transaction with a resize, wait for it to
-    // take effect before returning.
-    while (mResizeTransationPending) {
+    // if this is a synchronous transaction, wait for it to take effect before
+    // returning.
+    if (flags & eSynchronous) {
+        mTransationPending = true;
+    }
+    while (mTransationPending) {
         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.
             LOGW_IF(err == TIMED_OUT, "closeGlobalTransaction timed out!");
-            mResizeTransationPending = false;
+            mTransationPending = false;
             break;
         }
     }
@@ -1489,7 +1489,6 @@ uint32_t SurfaceFlinger::setClientStateLocked(
         if (what & eSizeChanged) {
             if (layer->setSize(s.w, s.h)) {
                 flags |= eTraversalNeeded;
-                mResizeTransationPending = true;
             }
         }
         if (what & eAlphaChanged) {
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 0e642c1..9ff080f 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -168,7 +168,7 @@ public:
     virtual sp<IMemoryHeap>             getCblk() const;
     virtual void                        bootFinished();
     virtual void                        setTransactionState(const Vector<ComposerState>& state,
-                                                            int orientation);
+                                                            int orientation, uint32_t flags);
     virtual status_t                    freezeDisplay(DisplayID dpy, uint32_t flags);
     virtual status_t                    unfreezeDisplay(DisplayID dpy, uint32_t flags);
     virtual int                         setOrientation(DisplayID dpy, int orientation, uint32_t flags);
@@ -341,7 +341,7 @@ private:
     volatile    int32_t                 mTransactionFlags;
                 Condition               mTransactionCV;
                 SortedVector< sp<LayerBase> > mLayerPurgatory;
-                bool                    mResizeTransationPending;
+                bool                    mTransationPending;
 
                 // protected by mStateLock (but we could use another lock)
                 GraphicPlane                mGraphicPlanes[1];