Auto merge of #6640 - mrobinson:memory-profiling-for-compositor, r=nnethercote

Add memory profiling for the compositor task

Currently only the BufferMap is recorded, but a later change will also
measure the memory usage of the compositor tree.

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5 files changed, 49 insertions, 7 deletions

diff --git a/components/compositing/compositor.rs b/components/compositing/compositor.rs
index 4f6a8bdbc71..79a0f08b150 100644
--- a/components/compositing/compositor.rs
+++ b/components/compositing/compositor.rs
@@ -243,6 +243,10 @@ fn initialize_png(width: usize, height: usize) -> (Vec<gl::GLuint>, Vec<gl::GLui
     (framebuffer_ids, texture_ids)
 }
 
+pub fn reporter_name() -> String {
+    "compositor-reporter".to_string()
+}
+
 impl<Window: WindowMethods> IOCompositor<Window> {
     fn new(window: Rc<Window>,
            sender: Box<CompositorProxy+Send>,
@@ -251,10 +255,11 @@ impl<Window: WindowMethods> IOCompositor<Window> {
            time_profiler_chan: time::ProfilerChan,
            mem_profiler_chan: mem::ProfilerChan)
            -> IOCompositor<Window> {
-        // Create an initial layer tree.
-        //
-        // TODO: There should be no initial layer tree until the painter creates one from the
-        // display list. This is only here because we don't have that logic in the painter yet.
+
+        // Register this thread as a memory reporter, via its own channel.
+        let reporter = box CompositorMemoryReporter(sender.clone_compositor_proxy());
+        mem_profiler_chan.send(mem::ProfilerMsg::RegisterReporter(reporter_name(), reporter));
+
         let window_size = window.framebuffer_size();
         let hidpi_factor = window.hidpi_factor();
         let composite_target = match opts::get().output_file {
@@ -333,6 +338,9 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                 let ConstellationChan(ref con_chan) = self.constellation_chan;
                 con_chan.send(ConstellationMsg::Exit).unwrap();
                 chan.send(()).unwrap();
+
+                self.mem_profiler_chan.send(mem::ProfilerMsg::UnregisterReporter(reporter_name()));
+
                 self.shutdown_state = ShutdownState::ShuttingDown;
             }
 
@@ -482,6 +490,18 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                 self.window.head_parsed();
             }
 
+            (Msg::CollectMemoryReports(reports_chan), ShutdownState::NotShuttingDown) => {
+                let mut reports = vec![];
+                let name = "compositor-task";
+                reports.push(mem::Report {
+                    path: path![name, "buffer-map"], size: self.buffer_map.mem(),
+                });
+                reports.push(mem::Report {
+                    path: path![name, "layer-tree"], size: self.scene.get_memory_usage(),
+                });
+                reports_chan.send(reports);
+            }
+
             // When we are shutting_down, we need to avoid performing operations
             // such as Paint that may crash because we have begun tearing down
             // the rest of our resources.
@@ -1702,3 +1722,20 @@ pub enum CompositingReason {
     /// The window has been zoomed.
     Zoom,
 }
+
+struct CompositorMemoryReporter(Box<CompositorProxy+'static+Send>);
+
+impl CompositorMemoryReporter {
+    pub fn send(&self, message: Msg) {
+        let CompositorMemoryReporter(ref proxy) = *self;
+        proxy.send(message);
+    }
+}
+
+impl mem::Reporter for CompositorMemoryReporter {
+    fn collect_reports(&self, reports_chan: mem::ReportsChan) -> bool {
+        // FIXME(mrobinson): The port should probably return the success of the message here.
+        self.send(Msg::CollectMemoryReports(reports_chan));
+        true
+    }
+}
diff --git a/components/compositing/compositor_task.rs b/components/compositing/compositor_task.rs
index b9738685f6b..dbf661e212d 100644
--- a/components/compositing/compositor_task.rs
+++ b/components/compositing/compositor_task.rs
@@ -35,7 +35,7 @@ use util::cursor::Cursor;
 /// process, and so forth.
 pub trait CompositorProxy : 'static + Send {
     /// Sends a message to the compositor.
-    fn send(&mut self, msg: Msg);
+    fn send(&self, msg: Msg);
     /// Clones the compositor proxy.
     fn clone_compositor_proxy(&self) -> Box<CompositorProxy+'static+Send>;
 }
@@ -62,7 +62,7 @@ impl CompositorReceiver for Receiver<Msg> {
     }
 }
 
-pub fn run_script_listener_thread(mut compositor_proxy: Box<CompositorProxy + 'static + Send>,
+pub fn run_script_listener_thread(compositor_proxy: Box<CompositorProxy + 'static + Send>,
                                   receiver: IpcReceiver<ScriptToCompositorMsg>) {
     while let Ok(msg) = receiver.recv() {
         match msg {
@@ -197,6 +197,8 @@ pub enum Msg {
     /// Signal that the paint task ignored the paint requests that carried
     /// these layer buffers, so that they can be re-added to the surface cache.
     ReturnUnusedLayerBuffers(Vec<Box<LayerBuffer>>),
+    /// Collect memory reports and send them back to the given mem::ReportsChan.
+    CollectMemoryReports(mem::ReportsChan),
 }
 
 impl Debug for Msg {
@@ -226,6 +228,7 @@ impl Debug for Msg {
             Msg::NewFavicon(..) => write!(f, "NewFavicon"),
             Msg::HeadParsed => write!(f, "HeadParsed"),
             Msg::ReturnUnusedLayerBuffers(..) => write!(f, "ReturnUnusedLayerBuffers"),
+            Msg::CollectMemoryReports(..) => write!(f, "CollectMemoryReports"),
         }
     }
 }
diff --git a/components/compositing/headless.rs b/components/compositing/headless.rs
index c4a4368d49b..6d2da22da43 100644
--- a/components/compositing/headless.rs
+++ b/components/compositing/headless.rs
@@ -112,6 +112,7 @@ impl CompositorEventListener for NullCompositor {
             Msg::NewFavicon(..) => {}
             Msg::HeadParsed => {}
             Msg::ReturnUnusedLayerBuffers(..) => {}
+            Msg::CollectMemoryReports(..) => {}
         }
         true
     }
diff --git a/components/compositing/lib.rs b/components/compositing/lib.rs
index a9cb24eeb8d..ef27074c96d 100644
--- a/components/compositing/lib.rs
+++ b/components/compositing/lib.rs
@@ -22,6 +22,7 @@ extern crate script_traits;
 extern crate msg;
 extern crate net;
 extern crate num;
+#[macro_use]
 extern crate profile_traits;
 extern crate net_traits;
 extern crate gfx_traits;
diff --git a/components/servo/Cargo.lock b/components/servo/Cargo.lock
index 94cb4e3c4ae..01d677f6870 100644
--- a/components/servo/Cargo.lock
+++ b/components/servo/Cargo.lock
@@ -679,7 +679,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "layers"
 version = "0.1.0"
-source = "git+https://github.com/servo/rust-layers#abc4f3803dde8d818343984a28d2e3d1fdad11a3"
+source = "git+https://github.com/servo/rust-layers#1c9628618803c161753fd9f00f5ef781660ce11e"
 dependencies = [
  "azure 0.1.0 (git+https://github.com/servo/rust-azure)",
  "cgl 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",