Revert r258965 aka reland r258122

gpu: Allow fences to check whether a flush has occurred

This skips waiting on a fence that was created but never committed.

BUG=352419,355275
TBR=piman@chromium.org

> Original Review URL: https://codereview.chromium.org/197563003

Review URL: https://codereview.chromium.org/222103008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@261383 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 10 insertions, 13 deletions

diff --git a/gpu/command_buffer/service/mailbox_manager_unittest.cc b/gpu/command_buffer/service/mailbox_manager_unittest.cc
index ae871f9..13005e6 100644
--- a/gpu/command_buffer/service/mailbox_manager_unittest.cc
+++ b/gpu/command_buffer/service/mailbox_manager_unittest.cc
@@ -8,7 +8,9 @@
 #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 {
@@ -188,6 +190,9 @@ 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() {
@@ -249,12 +254,15 @@ 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);
@@ -283,7 +291,6 @@ TEST_F(MailboxManagerSyncTest, ProduceSyncDestroy) {
   EXPECT_EQ(texture, manager_->ConsumeTexture(GL_TEXTURE_2D, name));
 
   // Synchronize
-  EXPECT_CALL(*gl_, Flush()).Times(1);
   manager_->PushTextureUpdates();
   manager2_->PullTextureUpdates();
 
@@ -305,7 +312,6 @@ TEST_F(MailboxManagerSyncTest, ProduceConsumeResize) {
   EXPECT_EQ(texture, manager_->ConsumeTexture(GL_TEXTURE_2D, name));
 
   // Synchronize
-  EXPECT_CALL(*gl_, Flush()).Times(1);
   manager_->PushTextureUpdates();
   manager2_->PullTextureUpdates();
 
@@ -334,7 +340,6 @@ 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);
@@ -396,7 +401,6 @@ TEST_F(MailboxManagerSyncTest, ProduceConsumeBidirectional) {
   manager2_->ProduceTexture(GL_TEXTURE_2D, name2, texture2);
 
   // Make visible.
-  EXPECT_CALL(*gl_, Flush()).Times(2);
   manager_->PushTextureUpdates();
   manager2_->PushTextureUpdates();
 
@@ -435,7 +439,6 @@ 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 0503fb1..d25368a 100644
--- a/gpu/command_buffer/service/mailbox_synchronizer.cc
+++ b/gpu/command_buffer/service/mailbox_synchronizer.cc
@@ -174,8 +174,6 @@ 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 462131f..9b31dac 100644
--- a/gpu/command_buffer/service/texture_definition.cc
+++ b/gpu/command_buffer/service/texture_definition.cc
@@ -278,12 +278,8 @@ void NativeImageBuffer::DidRead(gfx::GLImage* client) {
 
 void NativeImageBuffer::DidWrite(gfx::GLImage* client) {
   base::AutoLock lock(lock_);
-  // 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.
+  // Sharing semantics require the client to flush in order to make changes
+  // visible to other clients.
   write_fence_.reset(gfx::GLFence::CreateWithoutFlush());
   write_client_ = client;
   for (std::list<ClientInfo>::iterator it = client_infos_.begin();