Add cc::Surface ref counting.

cc/surfaces/surface_manager_ref_unittest.cc

Index: cc/surfaces/surface_manager_ref_unittest.cc
diff --git a/cc/surfaces/surface_manager_ref_unittest.cc b/cc/surfaces/surface_manager_ref_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..ed87c6029114ef75e9053bd93bd8a9a8054b4867
--- /dev/null
+++ b/cc/surfaces/surface_manager_ref_unittest.cc
@@ -0,0 +1,151 @@
+// Copyright 2016 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 <stddef.h>
+
+#include "base/memory/ptr_util.h"
+#include "cc/surfaces/surface_id.h"
+#include "cc/surfaces/surface_manager.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace cc {
+namespace {
+
+// Creates a new SurfaceId for the provided client and sink ids.
+constexpr SurfaceId MakeSurfaceId(uint32_t client_id, uint32_t sink_id) {
+  return SurfaceId(FrameSinkId(client_id, sink_id), LocalFrameId(1u, 1u));
+}
+
+// Creates a SurfaceId with the next LocalFrameId.
+SurfaceId NextSurfaceId(const SurfaceId& existing_id) {
+  return SurfaceId(
+      existing_id.frame_sink_id(),
+      LocalFrameId(existing_id.local_frame_id().local_id() + 1u, 1u));
+}
+
+constexpr SurfaceId kId1 = MakeSurfaceId(1, 0);
+constexpr SurfaceId kId2 = MakeSurfaceId(2, 0);
+constexpr SurfaceId kId3 = MakeSurfaceId(3, 0);
+
+class SurfaceManagerRefTest : public testing::Test {
+ public:
+  SurfaceManager& manager() { return *manager_; }
+
+  void SetUp() override {
+    testing::Test::SetUp();
+    manager_ = base::MakeUnique<SurfaceManager>();
+  }
+
+ protected:
+  std::unique_ptr<SurfaceManager> manager_;

[Fady Samuel, 2016/10/27 04:14:49]

No need to place it in a unique_ptr I think.

[kylechar, 2016/10/27 21:14:10]

I'd have to add a reset method to SurfaceManager otherwise to clear internal
state. It isn't expensive to build, so my personal preference is to wipe the
object and start with a new one.

+};
+
+}  // namespace
+
+TEST_F(SurfaceManagerRefTest, AddRemoveRef) {
+  manager().AddSurfaceIdReference(kId1, kId2);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId1), 0);

[Fady Samuel, 2016/10/27 04:14:49]

Hmm, what do we do about top-level surfaces? I guess we don't need refs on them?

[kylechar, 2016/10/27 21:14:10]

So my WIP patch beyond this one has a constant "SurfaceId kRootSuraceId" that
SurfaceManager knows about. kRootSuraceId is the only top level surface and
SurfaceManager skips checking references for it. The display root surfaces have
a ref kRootSuraceId -> display_root_surface_id. So when we resize a display we
just have to clear that one reference and all the old surfaces get GCd'.

+  EXPECT_EQ(manager().CountSurfaceReferences(kId2), 1);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId1), 1);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId2), 0);
+
+  manager().RemoveSurfaceIdReference(kId1, kId2);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId1), 0);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId2), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId1), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId2), 0);
+}
+
+TEST_F(SurfaceManagerRefTest, AddRemoveRefDouble) {
+  manager().AddSurfaceIdReference(kId1, kId2);
+  manager().AddSurfaceIdReference(kId2, kId3);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId1), 0);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId2), 1);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId3), 1);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId1), 1);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId2), 1);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId3), 0);
+
+  // Should remove references from id1 -> id2 and then since kId2 has zero
+  // references all references it holds should be removed.
+  manager().RemoveSurfaceIdReference(kId1, kId2);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId1), 0);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId2), 0);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId3), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId1), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId2), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId3), 0);
+}
+
+TEST_F(SurfaceManagerRefTest, AddRemoveSameFrameSinkId) {
+  SurfaceId next_id = NextSurfaceId(kId2);
+  ASSERT_EQ(kId2.frame_sink_id(), next_id.frame_sink_id());
+
+  manager().AddSurfaceIdReference(kId1, kId2);
+  manager().AddSurfaceIdReference(kId2, kId3);
+  manager().AddSurfaceIdReference(kId2, next_id);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId3), 1);
+  EXPECT_EQ(manager().CountSurfaceReferences(next_id), 1);
+
+  manager().RemoveSurfaceIdReference(kId2, kId3);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId3), 0);
+  EXPECT_EQ(manager().CountSurfaceReferences(next_id), 1);
+}
+
+TEST_F(SurfaceManagerRefTest, RemoveAllRoot) {
+  manager().AddSurfaceIdReference(kId1, kId2);
+  manager().AddSurfaceIdReference(kId2, kId3);
+  manager().RemoveAllReferencesForFrameSink(kId1.frame_sink_id());
+
+  EXPECT_EQ(manager().CountSurfaceReferences(kId2), 0);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId3), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId1), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId2), 0);
+}
+
+TEST_F(SurfaceManagerRefTest, RemoveAllLeafReference) {
+  manager().AddSurfaceIdReference(kId1, kId2);
+  manager().AddSurfaceIdReference(kId2, kId3);
+  manager().RemoveAllReferencesForFrameSink(kId3.frame_sink_id());
+
+  EXPECT_EQ(manager().CountSurfaceReferences(kId2), 1);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId3), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId1), 1);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId2), 0);
+}
+
+TEST_F(SurfaceManagerRefTest, RemoveAllRecursive) {
+  manager().AddSurfaceIdReference(kId1, kId2);
+  manager().AddSurfaceIdReference(kId2, kId3);
+  manager().RemoveAllReferencesForFrameSink(kId2.frame_sink_id());
+
+  EXPECT_EQ(manager().CountSurfaceReferences(kId2), 0);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId3), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId1), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId2), 0);
+}
+
+TEST_F(SurfaceManagerRefTest, RemoveAllRecusiveMultipleSurfaces) {

[Fady Samuel, 2016/10/27 04:14:49]

An interesting test or two or three to add would mix SurfaceSequences with
Surface references showing that we don't garbage collect incorrectly.

+  SurfaceId next_id = NextSurfaceId(kId2);
+  ASSERT_EQ(kId2.frame_sink_id(), next_id.frame_sink_id());
+
+  manager().AddSurfaceIdReference(kId1, kId2);
+  manager().AddSurfaceIdReference(kId1, next_id);
+  manager().AddSurfaceIdReference(kId2, kId3);
+  manager().AddSurfaceIdReference(next_id, kId3);
+
+  EXPECT_EQ(manager().CountSurfaceReferees(kId2), 1);
+  EXPECT_EQ(manager().CountSurfaceReferees(next_id), 1);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId3), 2);
+
+  manager().RemoveAllReferencesForFrameSink(next_id.frame_sink_id());
+
+  EXPECT_EQ(manager().CountSurfaceReferences(kId2), 0);
+  EXPECT_EQ(manager().CountSurfaceReferences(next_id), 0);
+  EXPECT_EQ(manager().CountSurfaceReferences(kId3), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(next_id), 0);
+  EXPECT_EQ(manager().CountSurfaceReferees(kId2), 0);
+}
+
+}  // namespace cc