Auto merge of #11607 - Ms2ger:shutdown-channels, r=asajeffrey

Remove the layout and paint shutdown channels

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components/constellation/pipeline.rs

@@ -55,8 +55,6 @@ pub struct Pipeline {
     /// A channel to the compositor.
     pub compositor_proxy: Box<CompositorProxy + 'static + Send>,
     pub chrome_to_paint_chan: Sender<ChromeToPaintMsg>,
-    pub layout_shutdown_port: IpcReceiver<()>,
-    pub paint_shutdown_port: IpcReceiver<()>,
     /// URL corresponding to the most recently-loaded page.
     pub url: Url,
     /// The title of the most recently-loaded page.
@@ -130,10 +128,6 @@ impl Pipeline {
         // probably requires a general low-memory strategy.
         let (layout_to_paint_chan, layout_to_paint_port) = util::ipc::optional_ipc_channel();
         let (chrome_to_paint_chan, chrome_to_paint_port) = channel();
-        let (paint_shutdown_chan, paint_shutdown_port) = ipc::channel()
-            .expect("Pipeline paint shutdown chan");
-        let (layout_shutdown_chan, layout_shutdown_port) = ipc::channel()
-            .expect("Pipeline layout shutdown chan");
         let (pipeline_chan, pipeline_port) = ipc::channel()
             .expect("Pipeline main chan");;
 
@@ -153,7 +147,6 @@ impl Pipeline {
                     panic_chan: state.panic_chan.clone(),
                     pipeline_port: pipeline_port,
                     layout_to_constellation_chan: state.layout_to_constellation_chan.clone(),
-                    layout_shutdown_chan: layout_shutdown_chan.clone(),
                     content_process_shutdown_chan: layout_content_process_shutdown_chan.clone(),
                 };
 
@@ -177,8 +170,7 @@ impl Pipeline {
                             state.panic_chan.clone(),
                             state.font_cache_thread.clone(),
                             state.time_profiler_chan.clone(),
-                            state.mem_profiler_chan.clone(),
-                            paint_shutdown_chan);
+                            state.mem_profiler_chan.clone());
 
         let mut child_process = None;
         if let Some((script_port, pipeline_port)) = content_ports {
@@ -232,7 +224,6 @@ impl Pipeline {
                 prefs: prefs::get_cloned(),
                 layout_to_paint_chan: layout_to_paint_chan,
                 pipeline_port: pipeline_port,
-                layout_shutdown_chan: layout_shutdown_chan,
                 pipeline_namespace_id: state.pipeline_namespace_id,
                 layout_content_process_shutdown_chan: layout_content_process_shutdown_chan,
                 layout_content_process_shutdown_port: layout_content_process_shutdown_port,
@@ -257,8 +248,6 @@ impl Pipeline {
                                      pipeline_chan,
                                      state.compositor_proxy,
                                      chrome_to_paint_chan,
-                                     layout_shutdown_port,
-                                     paint_shutdown_port,
                                      state.load_data.url,
                                      state.window_size);
 
@@ -271,8 +260,6 @@ impl Pipeline {
            layout_chan: IpcSender<LayoutControlMsg>,
            compositor_proxy: Box<CompositorProxy + 'static + Send>,
            chrome_to_paint_chan: Sender<ChromeToPaintMsg>,
-           layout_shutdown_port: IpcReceiver<()>,
-           paint_shutdown_port: IpcReceiver<()>,
            url: Url,
            size: Option<TypedSize2D<PagePx, f32>>)
            -> Pipeline {
@@ -283,8 +270,6 @@ impl Pipeline {
             layout_chan: layout_chan,
             compositor_proxy: compositor_proxy,
             chrome_to_paint_chan: chrome_to_paint_chan,
-            layout_shutdown_port: layout_shutdown_port,
-            paint_shutdown_port: paint_shutdown_port,
             url: url,
             title: None,
             children: vec!(),
@@ -407,7 +392,6 @@ pub struct UnprivilegedPipelineContent {
     prefs: HashMap<String, Pref>,
     pipeline_port: IpcReceiver<LayoutControlMsg>,
     pipeline_namespace_id: PipelineNamespaceId,
-    layout_shutdown_chan: IpcSender<()>,
     layout_content_process_shutdown_chan: IpcSender<()>,
     layout_content_process_shutdown_port: IpcReceiver<()>,
     script_content_process_shutdown_chan: IpcSender<()>,
@@ -452,7 +436,6 @@ impl UnprivilegedPipelineContent {
                     self.font_cache_thread,
                     self.time_profiler_chan,
                     self.mem_profiler_chan,
-                    self.layout_shutdown_chan,
                     self.layout_content_process_shutdown_chan,
                     self.webrender_api_sender);
 

components/gfx/paint_thread.rs

@@ -396,46 +396,38 @@ impl<C> PaintThread<C> where C: PaintListener + Send + 'static {
                   panic_chan: IpcSender<PanicMsg>,
                   font_cache_thread: FontCacheThread,
                   time_profiler_chan: time::ProfilerChan,
-                  mem_profiler_chan: mem::ProfilerChan,
-                  shutdown_chan: IpcSender<()>) {
+                  mem_profiler_chan: mem::ProfilerChan) {
         thread::spawn_named_with_send_on_panic(format!("PaintThread {:?}", id),
                                                thread_state::PAINT,
                                                move || {
-            {
-                // Ensures that the paint thread and graphics context are destroyed before the
-                // shutdown message.
-                let native_display = compositor.native_display();
-                let worker_threads = WorkerThreadProxy::spawn(native_display,
-                                                              font_cache_thread,
-                                                              time_profiler_chan.clone());
-
-                let mut paint_thread = PaintThread {
-                    id: id,
-                    _url: url,
-                    layout_to_paint_port: layout_to_paint_port,
-                    chrome_to_paint_port: chrome_to_paint_port,
-                    compositor: compositor,
-                    time_profiler_chan: time_profiler_chan,
-                    root_display_list: None,
-                    layer_map: HashMap::new(),
-                    paint_permission: false,
-                    current_epoch: None,
-                    worker_threads: worker_threads,
-                };
-
-                let reporter_name = format!("paint-reporter-{}", id);
-                mem_profiler_chan.run_with_memory_reporting(|| {
-                    paint_thread.start();
-                }, reporter_name, chrome_to_paint_chan, ChromeToPaintMsg::CollectReports);
-
-                // Tell all the worker threads to shut down.
-                for worker_thread in &mut paint_thread.worker_threads {
-                    worker_thread.exit()
-                }
-            }
+            let native_display = compositor.native_display();
+            let worker_threads = WorkerThreadProxy::spawn(native_display,
+                                                          font_cache_thread,
+                                                          time_profiler_chan.clone());
+
+            let mut paint_thread = PaintThread {
+                id: id,
+                _url: url,
+                layout_to_paint_port: layout_to_paint_port,
+                chrome_to_paint_port: chrome_to_paint_port,
+                compositor: compositor,
+                time_profiler_chan: time_profiler_chan,
+                root_display_list: None,
+                layer_map: HashMap::new(),
+                paint_permission: false,
+                current_epoch: None,
+                worker_threads: worker_threads,
+            };
+
+            let reporter_name = format!("paint-reporter-{}", id);
+            mem_profiler_chan.run_with_memory_reporting(|| {
+                paint_thread.start();
+            }, reporter_name, chrome_to_paint_chan, ChromeToPaintMsg::CollectReports);
 
-            debug!("paint_thread: shutdown_chan send");
-            let _ = shutdown_chan.send(());
+            // Tell all the worker threads to shut down.
+            for worker_thread in &mut paint_thread.worker_threads {
+                worker_thread.exit()
+            }
         }, Some(id), panic_chan);
     }
 

components/layout/layout_thread.rs

@@ -259,7 +259,6 @@ impl LayoutThreadFactory for LayoutThread {
               font_cache_thread: FontCacheThread,
               time_profiler_chan: time::ProfilerChan,
               mem_profiler_chan: mem::ProfilerChan,
-              shutdown_chan: IpcSender<()>,
               content_process_shutdown_chan: IpcSender<()>,
               webrender_api_sender: Option<webrender_traits::RenderApiSender>) {
         thread::spawn_named_with_send_on_panic(format!("LayoutThread {:?}", id),
@@ -286,7 +285,6 @@ impl LayoutThreadFactory for LayoutThread {
                     layout.start();
                 }, reporter_name, sender, Msg::CollectReports);
             }
-            let _ = shutdown_chan.send(());
             let _ = content_process_shutdown_chan.send(());
         }, Some(id), panic_chan);
     }
@@ -748,7 +746,6 @@ impl LayoutThread {
                              self.font_cache_thread.clone(),
                              self.time_profiler_chan.clone(),
                              self.mem_profiler_chan.clone(),
-                             info.layout_shutdown_chan,
                              info.content_process_shutdown_chan,
                              self.webrender_api.as_ref().map(|wr| wr.clone_sender()));
     }

components/layout_traits/lib.rs

@@ -48,7 +48,6 @@ pub trait LayoutThreadFactory {
               font_cache_thread: FontCacheThread,
               time_profiler_chan: time::ProfilerChan,
               mem_profiler_chan: mem::ProfilerChan,
-              shutdown_chan: IpcSender<()>,
               content_process_shutdown_chan: IpcSender<()>,
               webrender_api_sender: Option<webrender_traits::RenderApiSender>);
 }

components/script/layout_interface.rs

@@ -232,6 +232,5 @@ pub struct NewLayoutThreadInfo {
     pub script_chan: IpcSender<ConstellationControlMsg>,
     pub image_cache_thread: ImageCacheThread,
     pub paint_chan: OptionalOpaqueIpcSender,
-    pub layout_shutdown_chan: IpcSender<()>,
     pub content_process_shutdown_chan: IpcSender<()>,
 }

components/script/script_thread.rs

@@ -1129,7 +1129,6 @@ impl ScriptThread {
             panic_chan,
             pipeline_port,
             layout_to_constellation_chan,
-            layout_shutdown_chan,
             content_process_shutdown_chan,
         } = new_layout_info;
 
@@ -1147,7 +1146,6 @@ impl ScriptThread {
             paint_chan: paint_chan,
             script_chan: self.control_chan.clone(),
             image_cache_thread: self.image_cache_thread.clone(),
-            layout_shutdown_chan: layout_shutdown_chan,
             content_process_shutdown_chan: content_process_shutdown_chan,
         };
 

components/script_traits/lib.rs

@@ -104,8 +104,6 @@ pub struct NewLayoutInfo {
     pub panic_chan: IpcSender<PanicMsg>,
     /// A sender for the layout thread to communicate to the constellation.
     pub layout_to_constellation_chan: IpcSender<LayoutMsg>,
-    /// A shutdown channel so that layout can notify others when it's done.
-    pub layout_shutdown_chan: IpcSender<()>,
     /// A shutdown channel so that layout can tell the content process to shut down when it's done.
     pub content_process_shutdown_chan: IpcSender<()>,
 }