Bug 1677929 - Add a way to specify an ID for a generated frame, and propagate the ID to the APZSampler. r=gw,kats

This ID allows the compositor to track per-frame information from frame
generation, through APZ sampling, to the NotifyDidRender notification.

Differential Revision: https://phabricator.services.mozilla.com/D97535

gfx/layers/apz/public/APZSampler.h

@@ -57,11 +57,13 @@ class APZSampler {
    */
   static void SetSamplerThread(const wr::WrWindowId& aWindowId);
   static void SampleForWebRender(
-      const wr::WrWindowId& aWindowId, wr::Transaction* aTxn,
+      const wr::WrWindowId& aWindowId, const uint64_t* aGeneratedFrameId,
+      wr::Transaction* aTransaction,
       const wr::WrPipelineIdEpochs* aEpochsBeingRendered);
 
   void SetSampleTime(const SampleTime& aSampleTime);
-  void SampleForWebRender(wr::TransactionWrapper& aTxn,
+  void SampleForWebRender(const Maybe<VsyncId>& aGeneratedFrameId,
+                          wr::TransactionWrapper& aTxn,
                           const wr::WrPipelineIdEpochs* aEpochsBeingRendered);
 
   bool AdvanceAnimations(const SampleTime& aSampleTime);

gfx/layers/apz/src/APZCTreeManager.cpp

@@ -706,7 +706,8 @@ void APZCTreeManager::UpdateHitTestingTree(
 }
 
 void APZCTreeManager::SampleForWebRender(
-    wr::TransactionWrapper& aTxn, const SampleTime& aSampleTime,
+    const Maybe<VsyncId>& aVsyncId, wr::TransactionWrapper& aTxn,
+    const SampleTime& aSampleTime,
     const wr::WrPipelineIdEpochs* aEpochsBeingRendered) {
   AssertOnSamplerThread();
   MutexAutoLock lock(mMapLock);

gfx/layers/apz/src/APZCTreeManager.h

@@ -196,7 +196,8 @@ class APZCTreeManager : public IAPZCTreeManager, public APZInputBridge {
    * In effect it is the webrender equivalent of (part of) the code in
    * AsyncCompositionManager.
    */
-  void SampleForWebRender(wr::TransactionWrapper& aTxn,
+  void SampleForWebRender(const Maybe<VsyncId>& aVsyncId,
+                          wr::TransactionWrapper& aTxn,
                           const SampleTime& aSampleTime,
                           const wr::WrPipelineIdEpochs* aEpochsBeingRendered);
 

gfx/layers/apz/src/APZSampler.cpp

@@ -66,11 +66,14 @@ void APZSampler::SetSamplerThread(const wr::WrWindowId& aWindowId) {
 
 /*static*/
 void APZSampler::SampleForWebRender(
-    const wr::WrWindowId& aWindowId, wr::Transaction* aTransaction,
+    const wr::WrWindowId& aWindowId, const uint64_t* aGeneratedFrameId,
+    wr::Transaction* aTransaction,
     const wr::WrPipelineIdEpochs* aEpochsBeingRendered) {
   if (RefPtr<APZSampler> sampler = GetSampler(aWindowId)) {
     wr::TransactionWrapper txn(aTransaction);
-    sampler->SampleForWebRender(txn, aEpochsBeingRendered);
+    Maybe<VsyncId> vsyncId =
+        aGeneratedFrameId ? Some(VsyncId{*aGeneratedFrameId}) : Nothing();
+    sampler->SampleForWebRender(vsyncId, txn, aEpochsBeingRendered);
   }
 }
 
@@ -84,7 +87,7 @@ void APZSampler::SetSampleTime(const SampleTime& aSampleTime) {
 }
 
 void APZSampler::SampleForWebRender(
-    wr::TransactionWrapper& aTxn,
+    const Maybe<VsyncId>& aVsyncId, wr::TransactionWrapper& aTxn,
     const wr::WrPipelineIdEpochs* aEpochsBeingRendered) {
   AssertOnSamplerThread();
   SampleTime sampleTime;
@@ -121,7 +124,7 @@ void APZSampler::SampleForWebRender(
             ? now
             : mSampleTime;
   }
-  mApz->SampleForWebRender(aTxn, sampleTime, aEpochsBeingRendered);
+  mApz->SampleForWebRender(aVsyncId, aTxn, sampleTime, aEpochsBeingRendered);
 }
 
 bool APZSampler::AdvanceAnimations(const SampleTime& aSampleTime) {
@@ -331,10 +334,11 @@ void apz_register_sampler(mozilla::wr::WrWindowId aWindowId) {
 }
 
 void apz_sample_transforms(
-    mozilla::wr::WrWindowId aWindowId, mozilla::wr::Transaction* aTransaction,
+    mozilla::wr::WrWindowId aWindowId, const uint64_t* aGeneratedFrameId,
+    mozilla::wr::Transaction* aTransaction,
     const mozilla::wr::WrPipelineIdEpochs* aEpochsBeingRendered) {
-  mozilla::layers::APZSampler::SampleForWebRender(aWindowId, aTransaction,
+  mozilla::layers::APZSampler::SampleForWebRender(
-                                                  aEpochsBeingRendered);
+      aWindowId, aGeneratedFrameId, aTransaction, aEpochsBeingRendered);
 }
 
 void apz_deregister_sampler(mozilla::wr::WrWindowId aWindowId) {}

gfx/layers/wr/WebRenderBridgeParent.cpp

@@ -2091,7 +2091,7 @@ void WebRenderBridgeParent::MaybeGenerateFrame(VsyncId aId,
 #endif
 
   MOZ_ASSERT(generateFrame);
-  fastTxn.GenerateFrame();
+  fastTxn.GenerateFrame(aId);
   mApi->SendTransaction(fastTxn);
 
 #if defined(MOZ_WIDGET_ANDROID)

gfx/webrender_bindings/WebRenderAPI.cpp

@@ -252,8 +252,8 @@ void TransactionBuilder::ClearDisplayList(Epoch aEpoch,
   wr_transaction_clear_display_list(mTxn, aEpoch, aPipelineId);
 }
 
-void TransactionBuilder::GenerateFrame() {
+void TransactionBuilder::GenerateFrame(const VsyncId& aVsyncId) {
-  wr_transaction_generate_frame(mTxn);
+  wr_transaction_generate_frame(mTxn, aVsyncId.mId);
 }
 
 void TransactionBuilder::InvalidateRenderedFrame() {

gfx/webrender_bindings/WebRenderAPI.h

@@ -111,7 +111,7 @@ class TransactionBuilder final {
 
   void ClearDisplayList(Epoch aEpoch, wr::WrPipelineId aPipeline);
 
-  void GenerateFrame();
+  void GenerateFrame(const VsyncId& aVsyncId);
 
   void InvalidateRenderedFrame();
 

gfx/webrender_bindings/src/bindings.rs

@@ -917,6 +917,7 @@ extern "C" {
     fn apz_register_sampler(window_id: WrWindowId);
     fn apz_sample_transforms(
         window_id: WrWindowId,
+        generated_frame_id: *const u64,
         transaction: &mut Transaction,
         epochs_being_rendered: &WrPipelineIdEpochs,
     );
@@ -1014,8 +1015,17 @@ impl AsyncPropertySampler for SamplerCallback {
     fn sample(
         &self,
         _document_id: DocumentId,
+        generated_frame_id: Option<u64>,
         epochs_being_rendered: &FastHashMap<PipelineId, Epoch>,
     ) -> Vec<FrameMsg> {
+        let generated_frame_id_value;
+        let generated_frame_id: *const u64 = match generated_frame_id {
+            Some(id) => {
+                generated_frame_id_value = id;
+                &generated_frame_id_value
+            }
+            None => ptr::null_mut(),
+        };
         let mut transaction = Transaction::new();
         unsafe {
             // XXX: When we implement scroll-linked animations, we will probably
@@ -1023,6 +1033,7 @@ impl AsyncPropertySampler for SamplerCallback {
             omta_sample(self.window_id, &mut transaction);
             apz_sample_transforms(
                 self.window_id,
+                generated_frame_id,
                 &mut transaction,
                 &epochs_being_rendered.iter().map(WrPipelineIdAndEpoch::from).collect(),
             )
@@ -1823,8 +1834,8 @@ pub extern "C" fn wr_transaction_set_document_view(txn: &mut Transaction, doc_re
 }
 
 #[no_mangle]
-pub extern "C" fn wr_transaction_generate_frame(txn: &mut Transaction) {
+pub extern "C" fn wr_transaction_generate_frame(txn: &mut Transaction, id: u64) {
-    txn.generate_frame();
+    txn.generate_frame(id);
 }
 
 #[no_mangle]

gfx/webrender_bindings/webrender_ffi.h

@@ -92,7 +92,8 @@ void apz_deregister_updater(mozilla::wr::WrWindowId aWindowId);
 
 void apz_register_sampler(mozilla::wr::WrWindowId aWindowId);
 void apz_sample_transforms(
-    mozilla::wr::WrWindowId aWindowId, mozilla::wr::Transaction* aTransaction,
+    mozilla::wr::WrWindowId aWindowId, const uint64_t* aGeneratedFrameId,
+    mozilla::wr::Transaction* aTransaction,
     const mozilla::wr::WrPipelineIdEpochs* aPipelineEpochs);
 void apz_deregister_sampler(mozilla::wr::WrWindowId aWindowId);
 

gfx/wr/direct-composition/src/main_windows.rs

@@ -169,7 +169,7 @@ impl Rectangle {
             true,
         );
         transaction.set_root_pipeline(pipeline_id);
-        transaction.generate_frame();
+        transaction.generate_frame(0);
         self.api.send_transaction(self.document_id, transaction);
         rx.recv().unwrap();
         let renderer = self.renderer.as_mut().unwrap();

gfx/wr/example-compositor/compositor/src/main.rs

@@ -417,7 +417,7 @@ fn main() {
         );
     }
 
-    txn.generate_frame();
+    txn.generate_frame(0);
     api.send_transaction(document_id, txn);
 
     // Tick the compositor (in this sample, we don't block on UI events)
@@ -464,7 +464,7 @@ fn main() {
                 }
             }
 
-            txn.generate_frame();
+            txn.generate_frame(0);
             api.send_transaction(document_id, txn);
             current_epoch.0 += 1;
             time += 0.001;

gfx/wr/examples/animation.rs

@@ -195,7 +195,7 @@ impl Example for App {
                         colors: vec![],
                     },
                 );
-                txn.generate_frame();
+                txn.generate_frame(0);
                 api.send_transaction(document_id, txn);
             }
             _ => (),

gfx/wr/examples/basic.rs

@@ -313,7 +313,7 @@ impl Example for App {
         }
 
         if !txn.is_empty() {
-            txn.generate_frame();
+            txn.generate_frame(0);
             api.send_transaction(document_id, txn);
         }
 

gfx/wr/examples/common/boilerplate.rs

@@ -215,7 +215,7 @@ pub fn main_wrapper<E: Example>(
         true,
     );
     txn.set_root_pipeline(pipeline_id);
-    txn.generate_frame();
+    txn.generate_frame(0);
     api.send_transaction(document_id, txn);
 
     println!("Entering event loop");
@@ -312,7 +312,7 @@ pub fn main_wrapper<E: Example>(
                 builder.finalize(),
                 true,
             );
-            txn.generate_frame();
+            txn.generate_frame(0);
         }
         api.send_transaction(document_id, txn);
 

gfx/wr/examples/document.rs

@@ -129,7 +129,7 @@ impl Example for App {
                 builder.finalize(),
                 true,
             );
-            txn.generate_frame();
+            txn.generate_frame(0);
             api.send_transaction(doc.id, txn);
         }
     }

gfx/wr/examples/image_resize.rs

@@ -104,7 +104,7 @@ impl Example for App {
                     &DirtyRect::All,
                 );
                 let mut txn = Transaction::new();
-                txn.generate_frame();
+                txn.generate_frame(0);
                 api.send_transaction(document_id, txn);
             }
             _ => {}

gfx/wr/examples/multiwindow.rs

@@ -285,7 +285,7 @@ impl Window {
             true,
         );
         txn.set_root_pipeline(self.pipeline_id);
-        txn.generate_frame();
+        txn.generate_frame(0);
         api.send_transaction(self.document_id, txn);
 
         renderer.update();

gfx/wr/examples/scrolling.rs

@@ -182,11 +182,11 @@ impl Example for App {
                         ExternalScrollId(0, PipelineId::dummy()),
                         ScrollClamping::ToContentBounds,
                     );
-                    txn.generate_frame();
+                    txn.generate_frame(0);
                 }
                 if let Some(zoom) = zoom {
                     txn.set_pinch_zoom(ZoomFactor::new(zoom));
-                    txn.generate_frame();
+                    txn.generate_frame(0);
                 }
             }
             winit::WindowEvent::CursorMoved { position: LogicalPosition { x, y }, .. } => {
@@ -207,7 +207,7 @@ impl Example for App {
                     ScrollClamping::ToContentBounds,
                 );
 
-                txn.generate_frame();
+                txn.generate_frame(0);
             }
             winit::WindowEvent::MouseInput { .. } => {
                 let results = api.hit_test(

gfx/wr/webrender/src/render_api.rs

@@ -106,6 +106,38 @@ impl fmt::Debug for ResourceUpdate {
     }
 }
 
+/// Whether to generate a frame, and if so, an id that allows tracking this
+/// transaction through the various frame stages.
+#[derive(Clone, Debug)]
+pub enum GenerateFrame {
+    /// Generate a frame if something changed.
+    Yes {
+        /// An id that allows tracking the frame transaction through the various
+        /// frame stages. Specified by the caller of generate_frame().
+        id: u64,
+    },
+    /// Don't generate a frame even if something has changed.
+    No,
+}
+
+impl GenerateFrame {
+    ///
+    pub fn as_bool(&self) -> bool {
+        match self {
+            GenerateFrame::Yes { .. } => true,
+            GenerateFrame::No => false,
+        }
+    }
+
+    /// Return the frame ID, if a frame is generated.
+    pub fn id(&self) -> Option<u64> {
+        match self {
+            GenerateFrame::Yes { id } => Some(*id),
+            GenerateFrame::No => None,
+        }
+    }
+}
+
 /// A Transaction is a group of commands to apply atomically to a document.
 ///
 /// This mechanism ensures that:
@@ -127,8 +159,10 @@ pub struct Transaction {
     /// it will be applied directly on the render backend.
     use_scene_builder_thread: bool,
 
-    ///
+    /// Whether to generate a frame, and if so, an id that allows tracking this
-    generate_frame: bool,
+    /// transaction through the various frame stages. Specified by the caller of
+    /// generate_frame().
+    generate_frame: GenerateFrame,
 
     /// Set to true in order to force re-rendering even if WebRender can't internally
     /// detect that something has changed.
@@ -146,7 +180,7 @@ impl Transaction {
             resource_updates: Vec::new(),
             notifications: Vec::new(),
             use_scene_builder_thread: true,
-            generate_frame: false,
+            generate_frame: GenerateFrame::No,
             invalidate_rendered_frame: false,
             low_priority: false,
         }
@@ -171,7 +205,7 @@ impl Transaction {
 
     /// Returns true if the transaction has no effect.
     pub fn is_empty(&self) -> bool {
-        !self.generate_frame &&
+        !self.generate_frame.as_bool() &&
             !self.invalidate_rendered_frame &&
             self.scene_ops.is_empty() &&
             self.frame_ops.is_empty() &&
@@ -342,8 +376,8 @@ impl Transaction {
     /// as to when happened.
     ///
     /// [notifier]: trait.RenderNotifier.html#tymethod.new_frame_ready
-    pub fn generate_frame(&mut self) {
+    pub fn generate_frame(&mut self, id: u64) {
-        self.generate_frame = true;
+        self.generate_frame = GenerateFrame::Yes{ id };
     }
 
     /// Invalidate rendered frame. It ensure that frame will be rendered during
@@ -556,7 +590,7 @@ pub struct TransactionMsg {
     /// Updates to resources that persist across display lists.
     pub resource_updates: Vec<ResourceUpdate>,
     /// Whether to trigger frame building and rendering if something has changed.
-    pub generate_frame: bool,
+    pub generate_frame: GenerateFrame,
     /// Whether to force frame building and rendering even if no changes are internally
     /// observed.
     pub invalidate_rendered_frame: bool,
@@ -579,7 +613,7 @@ pub struct TransactionMsg {
 
 impl fmt::Debug for TransactionMsg {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        writeln!(f, "threaded={}, genframe={}, invalidate={}, low_priority={}",
+        writeln!(f, "threaded={}, genframe={:?}, invalidate={}, low_priority={}",
                         self.use_scene_builder_thread,
                         self.generate_frame,
                         self.invalidate_rendered_frame,
@@ -603,7 +637,7 @@ impl fmt::Debug for TransactionMsg {
 impl TransactionMsg {
     /// Returns true if this transaction has no effect.
     pub fn is_empty(&self) -> bool {
-        !self.generate_frame &&
+        !self.generate_frame.as_bool() &&
             !self.invalidate_rendered_frame &&
             self.scene_ops.is_empty() &&
             self.frame_ops.is_empty() &&
@@ -1230,7 +1264,7 @@ impl RenderApi {
             frame_ops: vec![msg],
             resource_updates: Vec::new(),
             notifications: Vec::new(),
-            generate_frame: false,
+            generate_frame: GenerateFrame::No,
             invalidate_rendered_frame: false,
             use_scene_builder_thread: false,
             low_priority: false,
@@ -1249,7 +1283,7 @@ impl RenderApi {
             frame_ops: Vec::new(),
             resource_updates: Vec::new(),
             notifications: Vec::new(),
-            generate_frame: false,
+            generate_frame: GenerateFrame::No,
             invalidate_rendered_frame: false,
             use_scene_builder_thread: false,
             low_priority: false,
@@ -1287,7 +1321,7 @@ impl RenderApi {
         self.resources.update(&mut transaction);
 
         transaction.use_scene_builder_thread |= !transaction.scene_ops.is_empty();
-        if transaction.generate_frame {
+        if transaction.generate_frame.as_bool() {
             transaction.profile.start_time(profiler::API_SEND_TIME);
             transaction.profile.start_time(profiler::TOTAL_FRAME_CPU_TIME);
         }
@@ -1312,7 +1346,7 @@ impl RenderApi {
             .map(|(txn, id)| {
                 let mut txn = txn.finalize(id);
                 self.resources.update(&mut txn);
-                if txn.generate_frame {
+                if txn.generate_frame.as_bool() {
                     txn.profile.start_time(profiler::API_SEND_TIME);
                     txn.profile.start_time(profiler::TOTAL_FRAME_CPU_TIME);
                 }

gfx/wr/webrender/src/render_backend.rs

@@ -1010,6 +1010,7 @@ impl RenderBackend {
                 txn.frame_ops.take(),
                 txn.notifications.take(),
                 txn.render_frame,
+                None,
                 txn.invalidate_rendered_frame,
                 frame_counter,
                 has_built_scene,
@@ -1347,7 +1348,7 @@ impl RenderBackend {
 
         let mut built_frame = false;
         for mut txn in txns {
-            if txn.generate_frame {
+            if txn.generate_frame.as_bool() {
                 txn.profile.end_time(profiler::API_SEND_TIME);
             }
 
@@ -1358,7 +1359,8 @@ impl RenderBackend {
                 txn.resource_updates.take(),
                 txn.frame_ops.take(),
                 txn.notifications.take(),
-                txn.generate_frame,
+                txn.generate_frame.as_bool(),
+                txn.generate_frame.id(),
                 txn.invalidate_rendered_frame,
                 frame_counter,
                 false
@@ -1395,6 +1397,7 @@ impl RenderBackend {
                     Vec::default(),
                     Vec::default(),
                     false,
+                    None,
                     false,
                     frame_counter,
                     false);
@@ -1414,6 +1417,7 @@ impl RenderBackend {
         mut frame_ops: Vec<FrameMsg>,
         mut notifications: Vec<NotificationRequest>,
         mut render_frame: bool,
+        generated_frame_id: Option<u64>,
         invalidate_rendered_frame: bool,
         frame_counter: &mut u32,
         has_built_scene: bool,
@@ -1430,7 +1434,7 @@ impl RenderBackend {
         // async transforms.
         if requested_frame || has_built_scene {
             if let Some(ref sampler) = self.sampler {
-                frame_ops.append(&mut sampler.sample(document_id,
+                frame_ops.append(&mut sampler.sample(document_id, generated_frame_id,
                                                      &doc.scene.pipeline_epochs));
             }
         }

gfx/wr/webrender/src/renderer.rs

@@ -6907,7 +6907,7 @@ pub trait AsyncPropertySampler {
     /// This is called for each transaction with the generate_frame flag set
     /// (i.e. that will trigger a render). The list of frame messages returned
     /// are processed as though they were part of the original transaction.
-    fn sample(&self, document_id: DocumentId,
+    fn sample(&self, document_id: DocumentId, generated_frame_id: Option<u64>,
               doc: &FastHashMap<PipelineId, Epoch>) -> Vec<FrameMsg>;
     /// This is called exactly once, when the render backend thread is about to
     /// terminate.

gfx/wr/webrender/src/scene_builder_thread.rs

@@ -687,7 +687,7 @@ impl SceneBuilderThread {
 
         Box::new(BuiltTransaction {
             document_id: txn.document_id,
-            render_frame: txn.generate_frame,
+            render_frame: txn.generate_frame.as_bool(),
             invalidate_rendered_frame: txn.invalidate_rendered_frame,
             built_scene,
             view: doc.view,

gfx/wr/wrench/src/rawtest.rs

@@ -107,7 +107,7 @@ impl<'a> RawtestHarness<'a> {
         );
         epoch.0 += 1;
 
-        txn.generate_frame();
+        txn.generate_frame(0);
         self.wrench.api.send_transaction(self.wrench.document_id, txn);
     }
 
@@ -1239,7 +1239,7 @@ impl<'a> RawtestHarness<'a> {
             builder.finalize(),
             false,
         );
-        txn.generate_frame();
+        txn.generate_frame(0);
 
         self.wrench.api.send_transaction(self.wrench.document_id, txn);
 
@@ -1274,7 +1274,7 @@ impl<'a> RawtestHarness<'a> {
         // 6. rebuild the scene and compare again
         let mut txn = Transaction::new();
         txn.set_root_pipeline(captured.root_pipeline_id.unwrap());
-        txn.generate_frame();
+        txn.generate_frame(0);
         self.wrench.api.send_transaction(captured.document_id, txn);
         let pixels2 = self.render_and_get_pixels(window_rect);
         self.compare_pixels(pixels0, pixels2, window_rect.size);
@@ -1305,7 +1305,7 @@ impl<'a> RawtestHarness<'a> {
             builder.finalize(),
             false,
         );
-        txn.generate_frame();
+        txn.generate_frame(0);
         self.wrench.api.send_transaction(doc_id, txn);
 
         // Ensure we get a notification from rendering the above, even though

gfx/wr/wrench/src/wrench.rs

@@ -606,7 +606,7 @@ impl Wrench {
             txn.scroll_node_with_id(*offset, *id, ScrollClamping::NoClamping);
         }
 
-        txn.generate_frame();
+        txn.generate_frame(0);
         self.api.send_transaction(self.document_id, txn);
     }
 
@@ -627,7 +627,7 @@ impl Wrench {
     pub fn refresh(&mut self) {
         self.begin_frame();
         let mut txn = Transaction::new();
-        txn.generate_frame();
+        txn.generate_frame(0);
         self.api.send_transaction(self.document_id, txn);
     }