Free worker context resources on idle.

gpu/command_buffer/client/gles2_implementation.h

Index: gpu/command_buffer/client/gles2_implementation.h
diff --git a/gpu/command_buffer/client/gles2_implementation.h b/gpu/command_buffer/client/gles2_implementation.h
index 0d6dffcf4e71ad7e33fddb3f0944246de04eb8cf..22c9cc52a18d6ff4df84c02832fc51061ae68b86 100644
--- a/gpu/command_buffer/client/gles2_implementation.h
+++ b/gpu/command_buffer/client/gles2_implementation.h
@@ -17,6 +17,7 @@
 #include <utility>
 #include <vector>
 
+#include "base/cancelable_callback.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
@@ -211,6 +212,12 @@ class GLES2_IMPL_EXPORT GLES2Implementation
       std::unique_ptr<ScopedVisibility> visibility) override;
   bool AnyClientsVisible() const override;
 
+  std::unique_ptr<ScopedBusy> ClientBecameBusy() override;
+  void ClientBecameNotBusy(std::unique_ptr<ScopedBusy> busy) override;
+  void SetIdleCallback(const base::Closure& callback,
+                       scoped_refptr<base::SingleThreadTaskRunner>
+                           callback_task_runner) override;
+
   // TODO(danakj): Move to ContextSupport once ContextProvider doesn't need to
   // intercept it.
   void SetLostContextCallback(const base::Closure& callback);
@@ -261,6 +268,7 @@ class GLES2_IMPL_EXPORT GLES2Implementation
                        const base::Closure& callback) override;
   void SignalQuery(uint32_t query, const base::Closure& callback) override;
   void SetAggressivelyFreeResources(bool aggressively_free_resources) override;
+  void TrimResources() override;
 
   // base::trace_event::MemoryDumpProvider implementation.
   bool OnMemoryDump(const base::trace_event::MemoryDumpArgs& args,
@@ -695,6 +703,9 @@ class GLES2_IMPL_EXPORT GLES2Implementation
 
   PixelStoreParams GetUnpackParameters(Dimension dimension);
 
+  void ScheduleIdleCallback();
+  void CancelIdleCallback();
+
   GLES2Util util_;
   GLES2CmdHelper* helper_;
   TransferBufferInterface* transfer_buffer_;
@@ -822,6 +833,11 @@ class GLES2_IMPL_EXPORT GLES2Implementation
   base::Closure lost_context_callback_;
   bool lost_context_callback_run_ = false;
 
+  base::Closure idle_callback_;
+  std::unique_ptr<base::CancelableClosure> pending_idle_callback_;

[danakj, 2016/08/23 01:26:25]

why unique_ptr it?

[ericrk, 2016/08/24 18:32:21]

You must create a CancelableClosure on the same thread you call cancel on, so
this lets us delay creation until we are on the idle_callback_task_runner_.

This can be re-worked if we go with a generation_id_, see my comments below.

+  scoped_refptr<base::SingleThreadTaskRunner> idle_callback_task_runner_;
+  bool is_idle_ = true;
+
   int current_trace_stack_;
 
   GpuControl* gpu_control_;