1 files changed, 140 insertions, 0 deletions
diff --git a/gfx/layers/ProfilerScreenshots.cpp b/gfx/layers/ProfilerScreenshots.cpp
new file mode 100644
index 0000000000..44bef9e410
--- /dev/null
+++ b/gfx/layers/ProfilerScreenshots.cpp
@@ -0,0 +1,140 @@
+/* -*- 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/. */
+
+#include "mozilla/layers/ProfilerScreenshots.h"
+
+#include "mozilla/TimeStamp.h"
+
+#include "GeckoProfiler.h"
+#include "gfxUtils.h"
+#include "nsThreadUtils.h"
+
+using namespace mozilla;
+using namespace mozilla::gfx;
+using namespace mozilla::layers;
+
+struct ScreenshotMarker {
+  static constexpr mozilla::Span<const char> MarkerTypeName() {
+    return mozilla::MakeStringSpan("CompositorScreenshot");
+  }
+  static void StreamJSONMarkerData(
+      mozilla::baseprofiler::SpliceableJSONWriter& aWriter,
+      const mozilla::ProfilerString8View& aScreenshotDataURL,
+      const mozilla::gfx::IntSize& aWindowSize, uint32_t aWindowIdentifier) {
+    if (aScreenshotDataURL.Length() != 0) {
+      aWriter.UniqueStringProperty("url", aScreenshotDataURL);
+    }
+
+    aWriter.IntProperty("windowID", aWindowIdentifier);
+
+    if (!aWindowSize.IsEmpty()) {
+      aWriter.DoubleProperty("windowWidth", aWindowSize.width);
+      aWriter.DoubleProperty("windowHeight", aWindowSize.height);
+    }
+  }
+  static mozilla::MarkerSchema MarkerTypeDisplay() {
+    return mozilla::MarkerSchema::SpecialFrontendLocation{};
+  }
+};
+
+uint32_t ProfilerScreenshots::sWindowCounter = 0;
+
+ProfilerScreenshots::ProfilerScreenshots()
+    : mMutex("ProfilerScreenshots::mMutex"),
+      mLiveSurfaceCount(0),
+      mWindowIdentifier(++sWindowCounter) {}
+
+ProfilerScreenshots::~ProfilerScreenshots() {
+  if (mWindowIdentifier) {
+    profiler_add_marker("CompositorScreenshotWindowDestroyed",
+                        geckoprofiler::category::GRAPHICS,
+                        MarkerThreadId::MainThread(), ScreenshotMarker{},
+                        /* aScreenshotDataURL */ "", mozilla::gfx::IntSize{},
+                        mWindowIdentifier);
+  }
+}
+
+/* static */
+bool ProfilerScreenshots::IsEnabled() {
+  return profiler_feature_active(ProfilerFeature::Screenshots);
+}
+
+void ProfilerScreenshots::SubmitScreenshot(
+    const gfx::IntSize& aOriginalSize, const IntSize& aScaledSize,
+    const TimeStamp& aTimeStamp,
+    const std::function<bool(DataSourceSurface*)>& aPopulateSurface) {
+  RefPtr<DataSourceSurface> backingSurface = TakeNextSurface();
+  if (!backingSurface) {
+    return;
+  }
+
+  MOZ_RELEASE_ASSERT(aScaledSize <= backingSurface->GetSize());
+
+  bool succeeded = aPopulateSurface(backingSurface);
+
+  if (!succeeded) {
+    PROFILER_MARKER_UNTYPED(
+        "NoCompositorScreenshot because aPopulateSurface callback failed",
+        GRAPHICS);
+    ReturnSurface(backingSurface);
+    return;
+  }
+
+  NS_DispatchBackgroundTask(NS_NewRunnableFunction(
+      "ProfilerScreenshots::SubmitScreenshot",
+      [self = RefPtr<ProfilerScreenshots>{this},
+       backingSurface = std::move(backingSurface),
+       windowIdentifier = mWindowIdentifier, originalSize = aOriginalSize,
+       scaledSize = aScaledSize, timeStamp = aTimeStamp]() {
+        // Create a new surface that wraps backingSurface's data but has the
+        // correct size.
+        DataSourceSurface::ScopedMap scopedMap(backingSurface,
+                                               DataSourceSurface::READ);
+        RefPtr<DataSourceSurface> surf =
+            Factory::CreateWrappingDataSourceSurface(
+                scopedMap.GetData(), scopedMap.GetStride(), scaledSize,
+                SurfaceFormat::B8G8R8A8);
+
+        // Encode surf to a JPEG data URL.
+        nsCString dataURL;
+        nsresult rv = gfxUtils::EncodeSourceSurface(
+            surf, ImageType::JPEG, u"quality=85"_ns, gfxUtils::eDataURIEncode,
+            nullptr, &dataURL);
+        if (NS_SUCCEEDED(rv)) {
+          // Add a marker with the data URL.
+          profiler_add_marker(
+              "CompositorScreenshot", geckoprofiler::category::GRAPHICS,
+              {MarkerThreadId::MainThread(),
+               MarkerTiming::InstantAt(timeStamp)},
+              ScreenshotMarker{}, dataURL, originalSize, windowIdentifier);
+        }
+
+        // Return backingSurface back to the surface pool.
+        self->ReturnSurface(backingSurface);
+      }));
+}
+
+already_AddRefed<DataSourceSurface> ProfilerScreenshots::TakeNextSurface() {
+  MutexAutoLock mon(mMutex);
+  if (!mAvailableSurfaces.IsEmpty()) {
+    RefPtr<DataSourceSurface> surf = mAvailableSurfaces[0];
+    mAvailableSurfaces.RemoveElementAt(0);
+    return surf.forget();
+  }
+  if (mLiveSurfaceCount >= 8) {
+    NS_WARNING(
+        "already 8 surfaces in flight, skipping capture for this composite");
+    return nullptr;
+  }
+  mLiveSurfaceCount++;
+  return Factory::CreateDataSourceSurface(ScreenshotSize(),
+                                          SurfaceFormat::B8G8R8A8);
+}
+
+void ProfilerScreenshots::ReturnSurface(DataSourceSurface* aSurface) {
+  MutexAutoLock mon(this->mMutex);
+  mAvailableSurfaces.AppendElement(aSurface);
+}