Wire up the JS engine's memory reporting.

SpiderMonkey provides an extremely fine-grained breakdown of memory
usage, but for Servo we aggregate the measurements into a small number
of coarse buckets, which seems appropriate for the current level of
detail provided by Servo's memory profiler. Sample output:
```
|   10.99 MiB -- pages
|       7.75 MiB -- url(http://html5demos.com/worker)
|          4.63 MiB -- js
|             2.00 MiB -- gc-heap
|                0.94 MiB -- decommitted
|                0.92 MiB -- used
|                0.09 MiB -- unused
|                0.05 MiB -- admin
|             1.44 MiB -- malloc-heap
|             1.19 MiB -- non-heap
|          [...]
|       3.24 MiB -- url(http://html5demos.com/js/worker-cruncher.js)
|          3.24 MiB -- js
|             1.17 MiB -- malloc-heap
|             1.06 MiB -- non-heap
|             1.00 MiB -- gc-heap
|                0.69 MiB -- used
|                0.19 MiB -- decommitted
|                0.09 MiB -- unused
|                0.03 MiB -- admin
```
Most of the changes are plumbing to get the script and worker tasks
communicating with the memory profiler task.

components/compositing/pipeline.rs

@@ -318,6 +318,7 @@ impl PipelineContent {
                                   self.resource_task,
                                   self.storage_task.clone(),
                                   self.image_cache_task.clone(),
+                                  self.mem_profiler_chan.clone(),
                                   self.devtools_chan,
                                   self.window_size,
                                   self.load_data.clone());

components/script/dom/bindings/global.rs

@@ -19,6 +19,7 @@ use script_task::{ScriptChan, ScriptPort, ScriptMsg, ScriptTask};
 
 use msg::constellation_msg::{PipelineId, WorkerId};
 use net_traits::ResourceTask;
+use profile_traits::mem;
 
 use js::{JSCLASS_IS_GLOBAL, JSCLASS_IS_DOMJSCLASS};
 use js::jsapi::{GetGlobalForObjectCrossCompartment};
@@ -82,7 +83,15 @@ impl<'a> GlobalRef<'a> {
         }
     }
 
-    /// Get `DevtoolsControlChan` to send messages to Devtools
+    /// Get a `mem::ProfilerChan` to send messages to the memory profiler task.
+    pub fn mem_profiler_chan(&self) -> mem::ProfilerChan {
+        match *self {
+            GlobalRef::Window(window) => window.mem_profiler_chan(),
+            GlobalRef::Worker(worker) => worker.mem_profiler_chan(),
+        }
+    }
+
+    /// Get a `DevtoolsControlChan` to send messages to Devtools
     /// task when available.
     pub fn devtools_chan(&self) -> Option<DevtoolsControlChan> {
         match *self {

components/script/dom/bindings/trace.rs

@@ -60,6 +60,7 @@ use smallvec::SmallVec1;
 use msg::compositor_msg::ScriptListener;
 use msg::constellation_msg::ConstellationChan;
 use net_traits::image::base::Image;
+use profile_traits::mem::ProfilerChan;
 use util::str::{LengthOrPercentageOrAuto};
 use std::cell::{Cell, UnsafeCell, RefCell};
 use std::collections::{HashMap, HashSet};
@@ -299,6 +300,7 @@ no_jsmanaged_fields!(CanvasGradientStop, LinearGradientStyle, RadialGradientStyl
 no_jsmanaged_fields!(LineCapStyle, LineJoinStyle, CompositionOrBlending);
 no_jsmanaged_fields!(RepetitionStyle);
 no_jsmanaged_fields!(WebGLError);
+no_jsmanaged_fields!(ProfilerChan);
 
 impl JSTraceable for Box<ScriptChan+Send> {
     #[inline]

components/script/dom/dedicatedworkerglobalscope.rs

@@ -29,6 +29,7 @@ use msg::constellation_msg::PipelineId;
 use devtools_traits::DevtoolsControlChan;
 
 use net_traits::{load_whole_resource, ResourceTask};
+use profile_traits::mem::{self, Reporter, ReportsChan};
 use util::task::spawn_named;
 use util::task_state;
 use util::task_state::{SCRIPT, IN_WORKER};
@@ -39,6 +40,7 @@ use js::jsval::UndefinedValue;
 use js::rust::Runtime;
 use url::Url;
 
+use rand::random;
 use std::rc::Rc;
 use std::sync::mpsc::{Sender, Receiver, channel};
 
@@ -64,6 +66,13 @@ impl ScriptChan for SendableWorkerScriptChan {
     }
 }
 
+impl Reporter for SendableWorkerScriptChan {
+    // Just injects an appropriate event into the worker task's queue.
+    fn collect_reports(&self, reports_chan: ReportsChan) -> bool {
+        self.send(ScriptMsg::CollectReports(reports_chan)).is_ok()
+    }
+}
+
 /// Set the `worker` field of a related DedicatedWorkerGlobalScope object to a particular
 /// value for the duration of this object's lifetime. This ensures that the related Worker
 /// object only lives as long as necessary (ie. while events are being executed), while
@@ -105,6 +114,7 @@ pub struct DedicatedWorkerGlobalScope {
 impl DedicatedWorkerGlobalScope {
     fn new_inherited(worker_url: Url,
                      id: PipelineId,
+                     mem_profiler_chan: mem::ProfilerChan,
                      devtools_chan: Option<DevtoolsControlChan>,
                      runtime: Rc<Runtime>,
                      resource_task: ResourceTask,
@@ -115,7 +125,7 @@ impl DedicatedWorkerGlobalScope {
         DedicatedWorkerGlobalScope {
             workerglobalscope: WorkerGlobalScope::new_inherited(
                 WorkerGlobalScopeTypeId::DedicatedGlobalScope, worker_url,
-                runtime, resource_task, devtools_chan),
+                runtime, resource_task, mem_profiler_chan, devtools_chan),
             id: id,
             receiver: receiver,
             own_sender: own_sender,
@@ -126,6 +136,7 @@ impl DedicatedWorkerGlobalScope {
 
     pub fn new(worker_url: Url,
                id: PipelineId,
+               mem_profiler_chan: mem::ProfilerChan,
                devtools_chan: Option<DevtoolsControlChan>,
                runtime: Rc<Runtime>,
                resource_task: ResourceTask,
@@ -134,7 +145,7 @@ impl DedicatedWorkerGlobalScope {
                receiver: Receiver<(TrustedWorkerAddress, ScriptMsg)>)
                -> Root<DedicatedWorkerGlobalScope> {
         let scope = box DedicatedWorkerGlobalScope::new_inherited(
-            worker_url, id, devtools_chan, runtime.clone(), resource_task,
+            worker_url, id, mem_profiler_chan, devtools_chan, runtime.clone(), resource_task,
             parent_sender, own_sender, receiver);
         DedicatedWorkerGlobalScopeBinding::Wrap(runtime.cx(), scope)
     }
@@ -143,6 +154,7 @@ impl DedicatedWorkerGlobalScope {
 impl DedicatedWorkerGlobalScope {
     pub fn run_worker_scope(worker_url: Url,
                             id: PipelineId,
+                            mem_profiler_chan: mem::ProfilerChan,
                             devtools_chan: Option<DevtoolsControlChan>,
                             worker: TrustedWorkerAddress,
                             resource_task: ResourceTask,
@@ -171,8 +183,12 @@ impl DedicatedWorkerGlobalScope {
             let runtime = Rc::new(ScriptTask::new_rt_and_cx());
             let serialized_url = url.serialize();
             let global = DedicatedWorkerGlobalScope::new(
-                url, id, devtools_chan, runtime.clone(), resource_task,
+                url, id, mem_profiler_chan.clone(), devtools_chan, runtime.clone(), resource_task,
                 parent_sender, own_sender, receiver);
+            // FIXME(njn): workers currently don't have a unique ID suitable for using in reporter
+            // registration (#6631), so we instead use a random number and cross our fingers.
+            let reporter_name = format!("worker-reporter-{}", random::<u64>());
+            println!("reporter_name = {}", reporter_name);
 
             {
                 let _ar = AutoWorkerReset::new(global.r(), worker);
@@ -188,6 +204,12 @@ impl DedicatedWorkerGlobalScope {
                         report_pending_exception(runtime.cx(), global.r().reflector().get_jsobject().get());
                     }
                 }
+
+                // Register this task as a memory reporter. This needs to be done within the
+                // scope of `_ar` otherwise script_chan_as_reporter() will panic.
+                let reporter = global.script_chan_as_reporter();
+                let msg = mem::ProfilerMsg::RegisterReporter(reporter_name.clone(), reporter);
+                mem_profiler_chan.send(msg);
             }
 
             loop {
@@ -199,12 +221,17 @@ impl DedicatedWorkerGlobalScope {
                     Err(_) => break,
                 }
             }
+
+            // Unregister this task as a memory reporter.
+            let msg = mem::ProfilerMsg::UnregisterReporter(reporter_name);
+            mem_profiler_chan.send(msg);
         });
     }
 }
 
 pub trait DedicatedWorkerGlobalScopeHelpers {
     fn script_chan(self) -> Box<ScriptChan+Send>;
+    fn script_chan_as_reporter(self) -> Box<Reporter+Send>;
     fn pipeline(self) -> PipelineId;
     fn new_script_pair(self) -> (Box<ScriptChan+Send>, Box<ScriptPort+Send>);
     fn process_event(self, msg: ScriptMsg);
@@ -218,6 +245,14 @@ impl<'a> DedicatedWorkerGlobalScopeHelpers for &'a DedicatedWorkerGlobalScope {
         }
     }
 
+    fn script_chan_as_reporter(self) -> Box<Reporter+Send> {
+        box SendableWorkerScriptChan {
+            sender: self.own_sender.clone(),
+            worker: self.worker.borrow().as_ref().unwrap().clone(),
+        }
+    }
+
+
     fn pipeline(self) -> PipelineId {
         self.id
     }
@@ -263,6 +298,13 @@ impl<'a> PrivateDedicatedWorkerGlobalScopeHelpers for &'a DedicatedWorkerGlobalS
                 let scope = WorkerGlobalScopeCast::from_ref(self);
                 scope.handle_fire_timer(timer_id);
             }
+            ScriptMsg::CollectReports(reports_chan) => {
+                let scope = WorkerGlobalScopeCast::from_ref(self);
+                let cx = scope.get_cx();
+                let path_seg = format!("url({})", scope.get_url());
+                let reports = ScriptTask::get_reports(cx, path_seg);
+                reports_chan.send(reports);
+            }
             _ => panic!("Unexpected message"),
         }
     }

components/script/dom/window.rs

@@ -45,6 +45,7 @@ use msg::webdriver_msg::{WebDriverJSError, WebDriverJSResult};
 use net_traits::ResourceTask;
 use net_traits::image_cache_task::{ImageCacheChan, ImageCacheTask};
 use net_traits::storage_task::{StorageTask, StorageType};
+use profile_traits::mem;
 use util::geometry::{self, Au, MAX_RECT};
 use util::opts;
 use util::str::{DOMString,HTML_SPACE_CHARACTERS};
@@ -64,7 +65,7 @@ use std::cell::{Cell, Ref, RefMut, RefCell};
 use std::collections::HashSet;
 use std::default::Default;
 use std::ffi::CString;
-use std::mem;
+use std::mem as std_mem;
 use std::rc::Rc;
 use std::sync::mpsc::{channel, Receiver, Sender};
 use std::sync::mpsc::TryRecvError::{Empty, Disconnected};
@@ -118,6 +119,9 @@ pub struct Window {
 
     next_worker_id: Cell<WorkerId>,
 
+    /// For sending messages to the memory profiler.
+    mem_profiler_chan: mem::ProfilerChan,
+
     /// For providing instructions to an optional devtools server.
     devtools_chan: Option<DevtoolsControlChan>,
     /// For sending timeline markers. Will be ignored if
@@ -538,6 +542,7 @@ pub trait WindowHelpers {
     fn window_size(self) -> Option<WindowSizeData>;
     fn get_url(self) -> Url;
     fn resource_task(self) -> ResourceTask;
+    fn mem_profiler_chan(self) -> mem::ProfilerChan;
     fn devtools_chan(self) -> Option<DevtoolsControlChan>;
     fn layout_chan(self) -> LayoutChan;
     fn constellation_chan(self) -> ConstellationChan;
@@ -721,7 +726,7 @@ impl<'a> WindowHelpers for &'a Window {
     /// layout task has finished any pending request messages.
     fn join_layout(self) {
         let mut layout_join_port = self.layout_join_port.borrow_mut();
-        if let Some(join_port) = mem::replace(&mut *layout_join_port, None) {
+        if let Some(join_port) = std_mem::replace(&mut *layout_join_port, None) {
             match join_port.try_recv() {
                 Err(Empty) => {
                     info!("script: waiting on layout");
@@ -823,6 +828,10 @@ impl<'a> WindowHelpers for &'a Window {
         self.resource_task.clone()
     }
 
+    fn mem_profiler_chan(self) -> mem::ProfilerChan {
+        self.mem_profiler_chan.clone()
+    }
+
     fn devtools_chan(self) -> Option<DevtoolsControlChan> {
         self.devtools_chan.clone()
     }
@@ -968,6 +977,7 @@ impl Window {
                image_cache_task: ImageCacheTask,
                resource_task: ResourceTask,
                storage_task: StorageTask,
+               mem_profiler_chan: mem::ProfilerChan,
                devtools_chan: Option<DevtoolsControlChan>,
                constellation_chan: ConstellationChan,
                layout_chan: LayoutChan,
@@ -993,6 +1003,7 @@ impl Window {
             page: page,
             navigator: Default::default(),
             image_cache_task: image_cache_task,
+            mem_profiler_chan: mem_profiler_chan,
             devtools_chan: devtools_chan,
             browser_context: DOMRefCell::new(None),
             performance: Default::default(),

components/script/dom/worker.rs

@@ -90,8 +90,8 @@ impl Worker {
         }
 
         DedicatedWorkerGlobalScope::run_worker_scope(
-            worker_url, global.pipeline(), global.devtools_chan(), worker_ref, resource_task, global.script_chan(),
-            sender, receiver);
+            worker_url, global.pipeline(), global.mem_profiler_chan(), global.devtools_chan(),
+            worker_ref, resource_task, global.script_chan(), sender, receiver);
 
         Ok(worker)
     }

components/script/dom/workerglobalscope.rs

@@ -23,6 +23,7 @@ use timers::{IsInterval, TimerId, TimerManager, TimerCallback};
 use devtools_traits::DevtoolsControlChan;
 
 use msg::constellation_msg::{PipelineId, WorkerId};
+use profile_traits::mem;
 use net_traits::{load_whole_resource, ResourceTask};
 use util::str::DOMString;
 
@@ -52,6 +53,7 @@ pub struct WorkerGlobalScope {
     console: MutNullableHeap<JS<Console>>,
     crypto: MutNullableHeap<JS<Crypto>>,
     timers: TimerManager,
+    mem_profiler_chan: mem::ProfilerChan,
     devtools_chan: Option<DevtoolsControlChan>,
 }
 
@@ -60,6 +62,7 @@ impl WorkerGlobalScope {
                          worker_url: Url,
                          runtime: Rc<Runtime>,
                          resource_task: ResourceTask,
+                         mem_profiler_chan: mem::ProfilerChan,
                          devtools_chan: Option<DevtoolsControlChan>) -> WorkerGlobalScope {
         WorkerGlobalScope {
             eventtarget: EventTarget::new_inherited(EventTargetTypeId::WorkerGlobalScope(type_id)),
@@ -72,10 +75,15 @@ impl WorkerGlobalScope {
             console: Default::default(),
             crypto: Default::default(),
             timers: TimerManager::new(),
+            mem_profiler_chan: mem_profiler_chan,
             devtools_chan: devtools_chan,
         }
     }
 
+    pub fn mem_profiler_chan(&self) -> mem::ProfilerChan {
+        self.mem_profiler_chan.clone()
+    }
+
     pub fn devtools_chan(&self) -> Option<DevtoolsControlChan> {
         self.devtools_chan.clone()
     }

components/script/lib.rs

@@ -57,6 +57,7 @@ extern crate time;
 extern crate canvas;
 extern crate canvas_traits;
 extern crate rand;
+#[macro_use]
 extern crate profile_traits;
 extern crate script_traits;
 extern crate selectors;