gpu: Implement the new fence syncs in mojo command buffer.

components/mus/gles2/command_buffer_driver.cc

Index: components/mus/gles2/command_buffer_driver.cc
diff --git a/components/mus/gles2/command_buffer_driver.cc b/components/mus/gles2/command_buffer_driver.cc
index 649216a4fb71e8df6e476de135a9516d0c2d13f0..2157ef790e31542e818f117517b0a1b1392b82e2 100644
--- a/components/mus/gles2/command_buffer_driver.cc
+++ b/components/mus/gles2/command_buffer_driver.cc
@@ -4,6 +4,7 @@
 
 #include "components/mus/gles2/command_buffer_driver.h"
 
+#include "base/atomic_sequence_num.h"
 #include "base/bind.h"
 #include "base/macros.h"
 #include "base/memory/shared_memory.h"
@@ -35,10 +36,19 @@
 
 namespace mus {
 
+namespace {
+
+base::StaticAtomicSequenceNumber g_next_command_buffer_id;

[David Yen, 2015/11/23 22:06:03]

Could this be an atomic sequence in gpu_state instead? They can all be in the
mojo namespace and we wouldn't need to add another namespace. Although
eventually when we add out of process mojo command buffers we will probably need
to add another one for that case.

[piman, 2015/11/23 22:22:52]

CommadnBufferDriver/CommandBufferImpl are for out-of-process command buffers.
The difference with chrome IPC is that the id here is genererated service-side
instead of client-side, so that's why it looks like it could be the same
namespace.
I think in the future we may decide to create the id client-side, so I think we
will want to separate MOJO_LOCAL from MOJO then - so why not now?

[David Yen, 2015/11/23 22:40:32]

If the IDs are always going to be generated service side then this will work
then. In that case let's keep this.

+
+}
+
 CommandBufferDriver::Client::~Client() {}
 
 CommandBufferDriver::CommandBufferDriver(scoped_refptr<GpuState> gpu_state)
-    : client_(nullptr), gpu_state_(gpu_state), weak_factory_(this) {}
+    : command_buffer_id_(g_next_command_buffer_id.GetNext()),
+      client_(nullptr),
+      gpu_state_(gpu_state),
+      weak_factory_(this) {}
 
 CommandBufferDriver::~CommandBufferDriver() {
   DestroyDecoder();
@@ -56,7 +66,10 @@ void CommandBufferDriver::Initialize(
   mojom::GpuCapabilitiesPtr capabilities =
       success ? mojom::GpuCapabilities::From(decoder_->GetCapabilities())
               : nullptr;
-  sync_client_->DidInitialize(success, capabilities.Pass());
+  sync_client_->DidInitialize(success,
+                              gpu::CommandBufferNamespace::MOJO,
+                              command_buffer_id_,
+                              capabilities.Pass());
 }
 
 bool CommandBufferDriver::MakeCurrent() {
@@ -113,6 +126,10 @@ bool CommandBufferDriver::DoInitialize(
   decoder_.reset(::gpu::gles2::GLES2Decoder::Create(context_group.get()));
   scheduler_.reset(new gpu::GpuScheduler(command_buffer_.get(), decoder_.get(),
                                          decoder_.get()));
+  sync_point_order_data_ = gpu::SyncPointOrderData::Create();
+  sync_point_client_ = gpu_state_->sync_point_manager()->CreateSyncPointClient(
+      sync_point_order_data_, gpu::CommandBufferNamespace::MOJO,
+      command_buffer_id_);
   decoder_->set_engine(scheduler_.get());
   decoder_->SetWaitSyncPointCallback(base::Bind(
       &CommandBufferDriver::OnWaitSyncPoint, base::Unretained(this)));
@@ -299,12 +316,8 @@ bool CommandBufferDriver::OnWaitSyncPoint(uint32_t sync_point) {
 }
 
 void CommandBufferDriver::OnFenceSyncRelease(uint64_t release) {
-  // TODO(dyen): Implement once CommandBufferID has been figured out and
-  // we have a SyncPointClient. It would probably look like what is commented
-  // out below:
-  // if (!sync_point_client_->client_state()->IsFenceSyncReleased(release))
-  //   sync_point_client_->ReleaseFenceSync(release);
-  NOTIMPLEMENTED();
+  if (!sync_point_client_->client_state()->IsFenceSyncReleased(release))
+    sync_point_client_->ReleaseFenceSync(release);
 }
 
 bool CommandBufferDriver::OnWaitFenceSync(
@@ -324,16 +337,13 @@ bool CommandBufferDriver::OnWaitFenceSync(
   if (release_state->IsFenceSyncReleased(release))
     return true;
 
-  // TODO(dyen): Implement once CommandBufferID has been figured out and
-  // we have a SyncPointClient. It would probably look like what is commented
-  // out below:
-  // scheduler_->SetScheduled(false);
-  // sync_point_client_->Wait(
-  //     release_state.get(),
-  //     release,
-  //     base::Bind(&CommandBufferDriver::OnSyncPointRetired,
-  //                weak_factory_.GetWeakPtr()));
-  NOTIMPLEMENTED();
+
+  scheduler_->SetScheduled(false);
+  sync_point_client_->Wait(
+      release_state.get(),
+      release,
+      base::Bind(&CommandBufferDriver::OnSyncPointRetired,
+                 weak_factory_.GetWeakPtr()));
   return scheduler_->scheduled();
 }