Bug 1141614 - Part 4: Expose cycle collection markers in the devtools frontend; r=jsantell

browser/devtools/performance/docs/markers.md

@@ -107,7 +107,8 @@ a setTimeout.
 
 ## GarbageCollection
 
-Emitted after a full GC has occurred (which will emit past incremental events).
+Emitted after a full GC cycle has completed (which is after any number of
+incremental slices).
 
 * DOMString causeName - The reason for a GC event to occur. A full list of
   GC reasons can be found [on MDN](https://developer.mozilla.org/en-US/docs/Tools/Debugger-API/Debugger.Memory#Debugger.Memory_Handler_Functions).
@@ -115,6 +116,17 @@ Emitted after a full GC has occurred (which will emit past incremental events).
   GC (smaller, quick GC events), and we have to walk the entire heap and
   GC everything marked, then the reason listed here is why.
 
+## nsCycleCollector::Collect
+
+An `nsCycleCollector::Collect` marker is emitted for each incremental cycle
+collection slice and each non-incremental cycle collection.
+
+# nsCycleCollector::ForgetSkippable
+
+`nsCycleCollector::ForgetSkippable` is presented as "Cycle Collection", but in
+reality it is preparation/pre-optimization for cycle collection, and not the
+actual tracing of edges and collecting of cycles.
+
 ## ConsoleTime
 
 A marker generated via `console.time()` and `console.timeEnd()`.

browser/devtools/performance/modules/logic/marker-utils.js

@@ -435,6 +435,13 @@ const Formatters = {
       return { "Restyle Hint": marker.restyleHint.replace(/eRestyle_/g, "") };
     }
   },
+
+  CycleCollectionFields: function (marker) {
+    let Type = PREFS["show-platform-data"]
+        ? marker.name
+        : marker.name.replace(/nsCycleCollector::/g, "");
+    return { Type };
+  },
 };
 
 exports.getMarkerLabel = getMarkerLabel;

browser/devtools/performance/modules/markers.js

@@ -113,6 +113,20 @@ const TIMELINE_BLUEPRINT = {
       { property: "nonincrementalReason", label: "Non-incremental Reason:" }
     ],
   },
+  "nsCycleCollector::Collect": {
+    group: 1,
+    colorName: "graphs-red",
+    collapseFunc: either(collapse.parent, collapse.child),
+    label: "Cycle Collection",
+    fields: Formatters.CycleCollectionFields,
+  },
+  "nsCycleCollector::ForgetSkippable": {
+    group: 1,
+    colorName: "graphs-red",
+    collapseFunc: either(collapse.parent, collapse.child),
+    label: "Cycle Collection",
+    fields: Formatters.CycleCollectionFields,
+  },
 
   /* Group 2 - User Controlled */
   "ConsoleTime": {