1 files changed, 94 insertions, 0 deletions
diff --git a/layout/base/AutoProfilerStyleMarker.h b/layout/base/AutoProfilerStyleMarker.h
new file mode 100644
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+++ b/layout/base/AutoProfilerStyleMarker.h
@@ -0,0 +1,94 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_AutoProfilerStyleMarker_h
+#define mozilla_AutoProfilerStyleMarker_h
+
+#include "mozilla/Attributes.h"
+#include "mozilla/ProfilerMarkers.h"
+#include "mozilla/ServoTraversalStatistics.h"
+#include "mozilla/TimeStamp.h"
+
+namespace mozilla {
+
+class MOZ_RAII AutoProfilerStyleMarker {
+ public:
+  explicit AutoProfilerStyleMarker(UniquePtr<ProfileChunkedBuffer> aCause,
+                                   const Maybe<uint64_t>& aInnerWindowID)
+      : mActive(profiler_can_accept_markers()),
+        mStartTime(TimeStamp::Now()),
+        mCause(std::move(aCause)),
+        mInnerWindowID(aInnerWindowID) {
+    if (!mActive) {
+      return;
+    }
+    MOZ_ASSERT(!ServoTraversalStatistics::sActive,
+               "Nested AutoProfilerStyleMarker");
+    ServoTraversalStatistics::sSingleton = ServoTraversalStatistics();
+    ServoTraversalStatistics::sActive = true;
+  }
+
+  ~AutoProfilerStyleMarker() {
+    if (!mActive) {
+      return;
+    }
+
+    struct StyleMarker {
+      static constexpr mozilla::Span<const char> MarkerTypeName() {
+        return mozilla::MakeStringSpan("Styles");
+      }
+      static void StreamJSONMarkerData(
+          baseprofiler::SpliceableJSONWriter& aWriter,
+          uint32_t aElementsTraversed, uint32_t aElementsStyled,
+          uint32_t aElementsMatched, uint32_t aStylesShared,
+          uint32_t aStylesReused) {
+        aWriter.IntProperty("elementsTraversed", aElementsTraversed);
+        aWriter.IntProperty("elementsStyled", aElementsStyled);
+        aWriter.IntProperty("elementsMatched", aElementsMatched);
+        aWriter.IntProperty("stylesShared", aStylesShared);
+        aWriter.IntProperty("stylesReused", aStylesReused);
+      }
+      static MarkerSchema MarkerTypeDisplay() {
+        using MS = MarkerSchema;
+        MS schema{MS::Location::markerChart, MS::Location::markerTable,
+                  MS::Location::timelineOverview};
+        schema.AddKeyLabelFormat("elementsTraversed", "Elements traversed",
+                                 MS::Format::integer);
+        schema.AddKeyLabelFormat("elementsStyled", "Elements styled",
+                                 MS::Format::integer);
+        schema.AddKeyLabelFormat("elementsMatched", "Elements matched",
+                                 MS::Format::integer);
+        schema.AddKeyLabelFormat("stylesShared", "Styles shared",
+                                 MS::Format::integer);
+        schema.AddKeyLabelFormat("stylesReused", "Styles reused",
+                                 MS::Format::integer);
+        return schema;
+      }
+    };
+
+    ServoTraversalStatistics::sActive = false;
+    profiler_add_marker("Styles", geckoprofiler::category::LAYOUT,
+                        {MarkerTiming::IntervalUntilNowFrom(mStartTime),
+                         MarkerStack::TakeBacktrace(std::move(mCause)),
+                         MarkerInnerWindowId(mInnerWindowID)},
+                        StyleMarker{},
+                        ServoTraversalStatistics::sSingleton.mElementsTraversed,
+                        ServoTraversalStatistics::sSingleton.mElementsStyled,
+                        ServoTraversalStatistics::sSingleton.mElementsMatched,
+                        ServoTraversalStatistics::sSingleton.mStylesShared,
+                        ServoTraversalStatistics::sSingleton.mStylesReused);
+  }
+
+ private:
+  bool mActive;
+  TimeStamp mStartTime;
+  UniquePtr<ProfileChunkedBuffer> mCause;
+  Maybe<uint64_t> mInnerWindowID;
+};
+
+}  // namespace mozilla
+
+#endif  // mozilla_AutoProfilerStyleMarker_h