Revert 258122 "gpu: Allow fences to check whether a flush has oc..."

Seems to expose some GL call sites without current context.
Reverting for the time being...

BUG=355275

> gpu: Allow fences to check whether a flush has occurred
> 
> This skips waiting on a fence that was created but never committed.
> 
> BUG=352419
> 
> Review URL: https://codereview.chromium.org/197563003

TBR=sievers@chromium.org

Review URL: https://codereview.chromium.org/209853004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@258965 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 13 insertions, 10 deletions

diff --git a/gpu/command_buffer/service/mailbox_manager_unittest.cc b/gpu/command_buffer/service/mailbox_manager_unittest.cc
index 13005e6..ae871f9 100644
--- a/gpu/command_buffer/service/mailbox_manager_unittest.cc
+++ b/gpu/command_buffer/service/mailbox_manager_unittest.cc
@@ -8,9 +8,7 @@
 #include "gpu/command_buffer/service/mailbox_synchronizer.h"
 #include "gpu/command_buffer/service/texture_manager.h"
 #include "testing/gtest/include/gtest/gtest.h"
-#include "ui/gl/gl_context_stub.h"
 #include "ui/gl/gl_mock.h"
-#include "ui/gl/gl_surface_stub.h"
 
 namespace gpu {
 namespace gles2 {
@@ -190,9 +188,6 @@ class MailboxManagerSyncTest : public MailboxManagerTest {
     manager2_ = new MailboxManager;
     gl_.reset(new ::testing::StrictMock< ::gfx::MockGLInterface>());
     ::gfx::MockGLInterface::SetGLInterface(gl_.get());
-    context_ = new gfx::GLContextStub();
-    surface_ = new gfx::GLSurfaceStub();
-    context_->MakeCurrent(surface_);
   }
 
   Texture* DefineTexture() {
@@ -254,15 +249,12 @@ class MailboxManagerSyncTest : public MailboxManagerTest {
   virtual void TearDown() {
     MailboxManagerTest::TearDown();
     MailboxSynchronizer::Terminate();
-    context_->ReleaseCurrent(NULL);
     ::gfx::MockGLInterface::SetGLInterface(NULL);
     gl_.reset();
   }
 
   scoped_ptr< ::testing::StrictMock< ::gfx::MockGLInterface> > gl_;
   scoped_refptr<MailboxManager> manager2_;
-  scoped_refptr<gfx::GLContext> context_;
-  scoped_refptr<gfx::GLSurface> surface_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MailboxManagerSyncTest);
@@ -291,6 +283,7 @@ TEST_F(MailboxManagerSyncTest, ProduceSyncDestroy) {
   EXPECT_EQ(texture, manager_->ConsumeTexture(GL_TEXTURE_2D, name));
 
   // Synchronize
+  EXPECT_CALL(*gl_, Flush()).Times(1);
   manager_->PushTextureUpdates();
   manager2_->PullTextureUpdates();
 
@@ -312,6 +305,7 @@ TEST_F(MailboxManagerSyncTest, ProduceConsumeResize) {
   EXPECT_EQ(texture, manager_->ConsumeTexture(GL_TEXTURE_2D, name));
 
   // Synchronize
+  EXPECT_CALL(*gl_, Flush()).Times(1);
   manager_->PushTextureUpdates();
   manager2_->PullTextureUpdates();
 
@@ -340,6 +334,7 @@ TEST_F(MailboxManagerSyncTest, ProduceConsumeResize) {
   EXPECT_TRUE(texture->GetLevelImage(GL_TEXTURE_2D, 0) == NULL);
 
   // Synchronize again
+  EXPECT_CALL(*gl_, Flush()).Times(1);
   manager_->PushTextureUpdates();
   SetupUpdateTexParamExpectations(
       kNewTextureId, GL_LINEAR, GL_LINEAR, GL_REPEAT, GL_REPEAT);
@@ -401,6 +396,7 @@ TEST_F(MailboxManagerSyncTest, ProduceConsumeBidirectional) {
   manager2_->ProduceTexture(GL_TEXTURE_2D, name2, texture2);
 
   // Make visible.
+  EXPECT_CALL(*gl_, Flush()).Times(2);
   manager_->PushTextureUpdates();
   manager2_->PushTextureUpdates();
 
@@ -439,6 +435,7 @@ TEST_F(MailboxManagerSyncTest, ProduceConsumeBidirectional) {
   Mock::VerifyAndClearExpectations(gl_.get());
 
   // Synchronize in both directions
+  EXPECT_CALL(*gl_, Flush()).Times(2);
   manager_->PushTextureUpdates();
   manager2_->PushTextureUpdates();
   // manager1 should see the change to texture2 mag_filter being applied.
diff --git a/gpu/command_buffer/service/mailbox_synchronizer.cc b/gpu/command_buffer/service/mailbox_synchronizer.cc
index d25368a..0503fb1 100644
--- a/gpu/command_buffer/service/mailbox_synchronizer.cc
+++ b/gpu/command_buffer/service/mailbox_synchronizer.cc
@@ -174,6 +174,8 @@ void MailboxSynchronizer::PushTextureUpdates(MailboxManager* manager) {
       textures_.insert(std::make_pair(texture, TextureVersion(group)));
     }
   }
+  // Make sure all write fences are flushed.
+  glFlush();
 }
 
 void MailboxSynchronizer::UpdateTextureLocked(Texture* texture,
diff --git a/gpu/command_buffer/service/texture_definition.cc b/gpu/command_buffer/service/texture_definition.cc
index 9b31dac..462131f 100644
--- a/gpu/command_buffer/service/texture_definition.cc
+++ b/gpu/command_buffer/service/texture_definition.cc
@@ -278,8 +278,12 @@ void NativeImageBuffer::DidRead(gfx::GLImage* client) {
 
 void NativeImageBuffer::DidWrite(gfx::GLImage* client) {
   base::AutoLock lock(lock_);
-  // Sharing semantics require the client to flush in order to make changes
-  // visible to other clients.
+  // TODO(sievers): crbug.com/352419
+  // This is super-risky. We need to somehow find out about when the current
+  // context gets flushed, so that we will only ever wait on the write fence
+  // (esp. from another context) if it was flushed and is guaranteed to clear.
+  // On the other hand, proactively flushing here is not feasible in terms
+  // of perf when there are multiple draw calls per frame.
   write_fence_.reset(gfx::GLFence::CreateWithoutFlush());
   write_client_ = client;
   for (std::list<ClientInfo>::iterator it = client_infos_.begin();