cc: Add rasterize and record micro benchmark.

cc/debug/rasterize_and_record_benchmark_impl.cc

+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "cc/debug/rasterize_and_record_benchmark_impl.h"
+
+#include <algorithm>
+#include <limits>
+
+#include "base/basictypes.h"
+#include "base/values.h"
+#include "cc/layers/layer_impl.h"
+#include "cc/layers/picture_layer_impl.h"
+#include "cc/trees/layer_tree_host_common.h"
+#include "cc/trees/layer_tree_host_impl.h"
+#include "ui/gfx/rect.h"
+
+namespace cc {
+
+namespace {
+
+const int kDefaultRasterizeRepeatCount = 100;
+
+base::TimeTicks Now() {
+  return base::TimeTicks::IsThreadNowSupported()
+             ? base::TimeTicks::ThreadNow()
+             : base::TimeTicks::HighResNow();
+}
+
+}  // namespace
+
+RasterizeAndRecordBenchmarkImpl::RasterizeAndRecordBenchmarkImpl(
+    scoped_refptr<base::MessageLoopProxy> origin_loop,
+    base::Value* value,
+    const MicroBenchmarkImpl::DoneCallback& callback)
+    : MicroBenchmarkImpl(callback, origin_loop),
+      rasterize_repeat_count_(kDefaultRasterizeRepeatCount) {
+  base::DictionaryValue* settings = NULL;
+  value->GetAsDictionary(&settings);
+  if (!settings)
+    return;
+
+  if (settings->HasKey("rasterize_repeat_count"))
+    settings->GetInteger("rasterize_repeat_count", &rasterize_repeat_count_);
+}
+
+RasterizeAndRecordBenchmarkImpl::~RasterizeAndRecordBenchmarkImpl() {}
+
+void RasterizeAndRecordBenchmarkImpl::DidCompleteCommit(
+    LayerTreeHostImpl* host) {
+  LayerTreeHostCommon::CallFunctionForSubtree(
+      host->RootLayer(),
+      base::Bind(&RasterizeAndRecordBenchmarkImpl::Run,
+                 base::Unretained(this)));
+
+  scoped_ptr<base::DictionaryValue> result(new base::DictionaryValue());
+  result->SetInteger("pixels_rasterized", rasterize_results_.pixels_rasterized);
+  result->SetDouble("rasterize_time_ms",
+                    rasterize_results_.total_best_time.InMillisecondsF());
+
+  NotifyDone(result.PassAs<base::Value>());
+}
+
+void RasterizeAndRecordBenchmarkImpl::Run(LayerImpl* layer) {
+  layer->RunMicroBenchmark(this);
+}
+
+void RasterizeAndRecordBenchmarkImpl::RunOnLayer(PictureLayerImpl* layer) {

[enne (OOO), 2013/11/11 19:47:14]

I don't understand why this has to run on the compositor thread.  It seems like
it'd be a lot simpler if you just ran it all on the main thread.

[vmpstr, 2013/11/11 22:38:38]

So I tried putting this on the main thread (which technically should work just
fine). However, I ran into a couple of issues:

- I can't get the ideal content scale / device scale: contents_scale_x for
PictureLayer seems to return 1 on any device I try. PictureLayerImpl returns the
correct thing.
- I can't use PictureLayerTiling set since it takes the PictureLayerImpl as a
client (but I can work around by using tiling data).

After discussion with ernstm, it seems that it would be better if we use the
correct scale... so sticking to compositor thread seems to be better (also we
can then use the tiling set coverage iterator, which should eliminate any
off-by-one errors that might creep up in tiling data iteration).

Let me know what your thoughts are.

+  if (layer->visible_content_rect().IsEmpty())
+    return;
+
+  PictureLayerTilingSet tiling_set(layer, layer->content_bounds());
+
+  PictureLayerTiling* tiling = tiling_set.AddTiling(layer->contents_scale_x());
+  tiling->CreateAllTilesForTesting();

[vmpstr, 2013/11/09 01:05:52]

This was the only way I could figure out how to create all tilings. This isn't
really release/production code (so for test fits), but I don't really like
calling this function since it kinda is the same binary as chrome.

Suggestions are more than welcome.

[enne (OOO), 2013/11/11 19:47:14]

I'm not sure why you need tiles here at all.  The iterator should still be able
to return you content rects even when there aren't tiles, yeah?

[vmpstr, 2013/11/11 22:38:38]

Geometry rect (from the coverage iterator) returns a clipped-to-viewport
post-scale rect. I could reconstruct the original pre-scale rect, but I can't
really undo the clip. That and I would have to expose picture_pile from
PictureLayerImpl, which I've tried to avoid (now I read it off the tile). This
seemed easier, but am I willing to change this if you insist.

+  for (PictureLayerTiling::CoverageIterator it(
+           tiling, layer->contents_scale_x(), layer->visible_content_rect());
+       it;
+       ++it) {
+    DCHECK(*it);
+
+    PicturePileImpl* picture_pile = (*it)->picture_pile();
+    gfx::Rect content_rect = (*it)->content_rect();
+    float contents_scale = (*it)->contents_scale();
+
+    base::TimeDelta min_time =
+        base::TimeDelta::FromInternalValue(std::numeric_limits<int64>::max());
+    for (int i = 0; i < rasterize_repeat_count_; ++i) {
+      SkBitmap bitmap;
+      bitmap.setConfig(SkBitmap::kARGB_8888_Config,
+                       content_rect.width(),
+                       content_rect.height());
+      bitmap.allocPixels();
+
+      SkBitmapDevice device(bitmap);
+      SkCanvas canvas(&device);
+
+      base::TimeTicks start = Now();
+      picture_pile->RasterToBitmap(&canvas, content_rect, contents_scale, NULL);
+      base::TimeTicks end = Now();
+      base::TimeDelta duration = end - start;
+      if (duration < min_time)
+        min_time = duration;
+    }
+
+    rasterize_results_.pixels_rasterized +=
+        content_rect.width() * content_rect.height();
+    rasterize_results_.total_best_time += min_time;
+  }
+}
+
+RasterizeAndRecordBenchmarkImpl::RasterizeResults::RasterizeResults()
+    : pixels_rasterized(0) {}
+
+RasterizeAndRecordBenchmarkImpl::RasterizeResults::~RasterizeResults() {}
+
+}  // namespace cc