Revert "Revert 113479 - Revert "Revert 113250 - Add CommandBuffer::SetGetBuffer""

This reverts commit 84677847c10d0319d8d996aea9b310add85c0bd3.

TEST=ran browser tests on OSX
BUG=103989
TBR=apatrick@chromiu.org

Review URL: http://codereview.chromium.org/8919014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@114114 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 32 insertions, 91 deletions

diff --git a/content/common/gpu/gpu_command_buffer_stub.cc b/content/common/gpu/gpu_command_buffer_stub.cc
index ff2ab82..8d17117 100644
--- a/content/common/gpu/gpu_command_buffer_stub.cc
+++ b/content/common/gpu/gpu_command_buffer_stub.cc
@@ -87,6 +87,8 @@ bool GpuCommandBufferStub::OnMessageReceived(const IPC::Message& message) {
   IPC_BEGIN_MESSAGE_MAP(GpuCommandBufferStub, message)
     IPC_MESSAGE_HANDLER_DELAY_REPLY(GpuCommandBufferMsg_Initialize,
                                     OnInitialize);
+    IPC_MESSAGE_HANDLER_DELAY_REPLY(GpuCommandBufferMsg_SetGetBuffer,
+                                    OnSetGetBuffer);
     IPC_MESSAGE_HANDLER_DELAY_REPLY(GpuCommandBufferMsg_SetParent,
                                     OnSetParent);
     IPC_MESSAGE_HANDLER_DELAY_REPLY(GpuCommandBufferMsg_GetState, OnGetState);
@@ -163,8 +165,6 @@ void GpuCommandBufferStub::OnInitializeFailed(IPC::Message* reply_message) {
 }
 
 void GpuCommandBufferStub::OnInitialize(
-    base::SharedMemoryHandle ring_buffer,
-    int32 size,
     IPC::Message* reply_message) {
   DCHECK(!command_buffer_.get());
 
@@ -172,19 +172,7 @@ void GpuCommandBufferStub::OnInitialize(
 
   command_buffer_.reset(new gpu::CommandBufferService);
 
-#if defined(OS_WIN)
-  // Windows dups the shared memory handle it receives into the current process
-  // and closes it when this variable goes out of scope.
-  base::SharedMemory shared_memory(ring_buffer,
-                                   false,
-                                   channel_->renderer_process());
-#else
-  // POSIX receives a dup of the shared memory handle and closes the dup when
-  // this variable goes out of scope.
-  base::SharedMemory shared_memory(ring_buffer, false);
-#endif
-
-  if (!command_buffer_->Initialize(&shared_memory, size)) {
+  if (!command_buffer_->Initialize()) {
     DLOG(ERROR) << "CommandBufferService failed to initialize.\n";
     OnInitializeFailed(reply_message);
     return;
@@ -266,6 +254,9 @@ void GpuCommandBufferStub::OnInitialize(
   command_buffer_->SetPutOffsetChangeCallback(
       base::Bind(&gpu::GpuScheduler::PutChanged,
                  base::Unretained(scheduler_.get())));
+  command_buffer_->SetGetBufferChangeCallback(
+      base::Bind(&gpu::GpuScheduler::SetGetBuffer,
+                 base::Unretained(scheduler_.get())));
   command_buffer_->SetParseErrorCallback(
       base::Bind(&GpuCommandBufferStub::OnParseError, base::Unretained(this)));
   scheduler_->SetScheduledCallback(
@@ -291,6 +282,12 @@ void GpuCommandBufferStub::OnInitialize(
                                  "offscreen", surface_->IsOffscreen());
 }
 
+void GpuCommandBufferStub::OnSetGetBuffer(
+    int32 shm_id, IPC::Message* reply_message) {
+  command_buffer_->SetGetBuffer(shm_id);
+  Send(reply_message);
+}
+
 void GpuCommandBufferStub::OnSetParent(int32 parent_route_id,
                                        uint32 parent_texture_id,
                                        IPC::Message* reply_message) {
diff --git a/content/common/gpu/gpu_command_buffer_stub.h b/content/common/gpu/gpu_command_buffer_stub.h
index 50e2b23..8fbfb79 100644
--- a/content/common/gpu/gpu_command_buffer_stub.h
+++ b/content/common/gpu/gpu_command_buffer_stub.h
@@ -93,9 +93,8 @@ class GpuCommandBufferStub
   void OnInitializeFailed(IPC::Message* reply_message);
 
   // Message handlers:
-  void OnInitialize(base::SharedMemoryHandle ring_buffer,
-                    int32 size,
-                    IPC::Message* reply_message);
+  void OnInitialize(IPC::Message* reply_message);
+  void OnSetGetBuffer(int32 shm_id, IPC::Message* reply_message);
   void OnSetParent(int32 parent_route_id,
                    uint32 parent_texture_id,
                    IPC::Message* reply_message);
diff --git a/content/common/gpu/gpu_messages.h b/content/common/gpu/gpu_messages.h
index e5cab60..7099747 100644
--- a/content/common/gpu/gpu_messages.h
+++ b/content/common/gpu/gpu_messages.h
@@ -311,11 +311,13 @@ IPC_MESSAGE_CONTROL0(GpuChannelMsg_CloseChannel)
 // Initialize a command buffer with the given number of command entries.
 // Returns the shared memory handle for the command buffer mapped to the
 // calling process.
-IPC_SYNC_MESSAGE_ROUTED2_1(GpuCommandBufferMsg_Initialize,
-                           base::SharedMemoryHandle /* ring_buffer */,
-                           int32 /* size */,
+IPC_SYNC_MESSAGE_ROUTED0_1(GpuCommandBufferMsg_Initialize,
                            bool /* result */)
 
+// Sets the shared memory buffer used for commands.
+IPC_SYNC_MESSAGE_ROUTED1_0(GpuCommandBufferMsg_SetGetBuffer,
+                           int32 /* shm_id */)
+
 // Sets the parent command buffer. This allows the parent and child to share
 // textures.
 IPC_SYNC_MESSAGE_ROUTED2_1(GpuCommandBufferMsg_SetParent,
diff --git a/content/renderer/gpu/command_buffer_proxy.cc b/content/renderer/gpu/command_buffer_proxy.cc
index 86420ae..d51f840 100644
--- a/content/renderer/gpu/command_buffer_proxy.cc
+++ b/content/renderer/gpu/command_buffer_proxy.cc
@@ -25,8 +25,7 @@ using gpu::Buffer;
 CommandBufferProxy::CommandBufferProxy(
     GpuChannelHost* channel,
     int route_id)
-    : num_entries_(0),
-      channel_(channel),
+    : channel_(channel),
       route_id_(route_id),
       flush_count_(0) {
 }
@@ -93,41 +92,13 @@ void CommandBufferProxy::SetChannelErrorCallback(
   channel_error_callback_ = callback;
 }
 
-bool CommandBufferProxy::Initialize(int32 size) {
-  DCHECK(!ring_buffer_.get());
-
+bool CommandBufferProxy::Initialize() {
   ChildThread* child_thread = ChildThread::current();
   if (!child_thread)
     return false;
 
-  base::SharedMemoryHandle handle;
-  if (!child_thread->Send(new ChildProcessHostMsg_SyncAllocateSharedMemory(
-      size,
-      &handle))) {
-    return false;
-  }
-
-  if (!base::SharedMemory::IsHandleValid(handle))
-    return false;
-
-#if defined(OS_POSIX)
-  handle.auto_close = false;
-#endif
-
-  // Take ownership of shared memory. This will close the handle if Send below
-  // fails. Otherwise, callee takes ownership before this variable
-  // goes out of scope.
-  base::SharedMemory shared_memory(handle, false);
-
-  return Initialize(&shared_memory, size);
-}
-
-bool CommandBufferProxy::Initialize(base::SharedMemory* buffer, int32 size) {
   bool result;
-  if (!Send(new GpuCommandBufferMsg_Initialize(route_id_,
-                                               buffer->handle(),
-                                               size,
-                                               &result))) {
+  if (!Send(new GpuCommandBufferMsg_Initialize(route_id_, &result))) {
     LOG(ERROR) << "Could not send GpuCommandBufferMsg_Initialize.";
     return false;
   }
@@ -137,39 +108,9 @@ bool CommandBufferProxy::Initialize(base::SharedMemory* buffer, int32 size) {
     return false;
   }
 
-  base::SharedMemoryHandle handle;
-  if (!buffer->GiveToProcess(base::GetCurrentProcessHandle(), &handle)) {
-    LOG(ERROR) << "Failed to duplicate command buffer handle.";
-    return false;
-  }
-
-  ring_buffer_.reset(new base::SharedMemory(handle, false));
-  if (!ring_buffer_->Map(size)) {
-    LOG(ERROR) << "Failed to map shared memory for command buffer.";
-    ring_buffer_.reset();
-    return false;
-  }
-
-  num_entries_ = size / sizeof(gpu::CommandBufferEntry);
   return true;
 }
 
-Buffer CommandBufferProxy::GetRingBuffer() {
-  DCHECK(ring_buffer_.get());
-  // Return locally cached ring buffer.
-  Buffer buffer;
-  if (ring_buffer_.get()) {
-    buffer.ptr = ring_buffer_->memory();
-    buffer.size = num_entries_ * sizeof(gpu::CommandBufferEntry);
-    buffer.shared_memory = ring_buffer_.get();
-  } else {
-    buffer.ptr = NULL;
-    buffer.size = 0;
-    buffer.shared_memory = NULL;
-  }
-  return buffer;
-}
-
 gpu::CommandBuffer::State CommandBufferProxy::GetState() {
   // Send will flag state with lost context if IPC fails.
   if (last_state_.error == gpu::error::kNoError) {
@@ -214,6 +155,13 @@ gpu::CommandBuffer::State CommandBufferProxy::FlushSync(int32 put_offset,
   return last_state_;
 }
 
+void CommandBufferProxy::SetGetBuffer(int32 shm_id) {
+  if (last_state_.error != gpu::error::kNoError)
+    return;
+
+  Send(new GpuCommandBufferMsg_SetGetBuffer(route_id_, shm_id));
+}
+
 void CommandBufferProxy::SetGetOffset(int32 get_offset) {
   // Not implemented in proxy.
   NOTREACHED();
diff --git a/content/renderer/gpu/command_buffer_proxy.h b/content/renderer/gpu/command_buffer_proxy.h
index 551e1ca..6591621 100644
--- a/content/renderer/gpu/command_buffer_proxy.h
+++ b/content/renderer/gpu/command_buffer_proxy.h
@@ -43,13 +43,12 @@ class CommandBufferProxy : public gpu::CommandBuffer,
   int route_id() const { return route_id_; }
 
   // CommandBuffer implementation:
-  virtual bool Initialize(int32 size) OVERRIDE;
-  virtual bool Initialize(base::SharedMemory* buffer, int32 size) OVERRIDE;
-  virtual gpu::Buffer GetRingBuffer() OVERRIDE;
+  virtual bool Initialize() OVERRIDE;
   virtual State GetState() OVERRIDE;
   virtual State GetLastState() OVERRIDE;
   virtual void Flush(int32 put_offset) OVERRIDE;
   virtual State FlushSync(int32 put_offset, int32 last_known_get) OVERRIDE;
+  virtual void SetGetBuffer(int32 shm_id) OVERRIDE;
   virtual void SetGetOffset(int32 get_offset) OVERRIDE;
   virtual int32 CreateTransferBuffer(size_t size, int32 id_request) OVERRIDE;
   virtual int32 RegisterTransferBuffer(base::SharedMemory* shared_memory,
@@ -104,10 +103,6 @@ class CommandBufferProxy : public gpu::CommandBuffer,
   void OnDestroyed(gpu::error::ContextLostReason reason);
   void OnEchoAck();
 
-  // As with the service, the client takes ownership of the ring buffer.
-  int32 num_entries_;
-  scoped_ptr<base::SharedMemory> ring_buffer_;
-
   // Local cache of id to transfer buffer mapping.
   typedef std::map<int32, gpu::Buffer> TransferBufferMap;
   TransferBufferMap transfer_buffers_;
diff --git a/content/renderer/gpu/renderer_gl_context.cc b/content/renderer/gpu/renderer_gl_context.cc
index 03f6715..8fa9262 100644
--- a/content/renderer/gpu/renderer_gl_context.cc
+++ b/content/renderer/gpu/renderer_gl_context.cc
@@ -380,7 +380,7 @@ bool RendererGLContext::Initialize(bool onscreen,
     TRACE_EVENT0("gpu",
                  "RendererGLContext::Initialize::InitializeCommandBuffer");
     // Initiaize the command buffer.
-    if (!command_buffer_->Initialize(kCommandBufferSize)) {
+    if (!command_buffer_->Initialize()) {
       Destroy();
       return false;
     }