gpu: Reuse transfer buffers more aggresively

gpu/command_buffer/client/cmd_buffer_helper.h

Index: gpu/command_buffer/client/cmd_buffer_helper.h
diff --git a/gpu/command_buffer/client/cmd_buffer_helper.h b/gpu/command_buffer/client/cmd_buffer_helper.h
index a50dc7bfe4e4e73e4bc4ce392bc1cb85e32182be..eeb6387e1f72d44d3eb42cf24dafcf89ac7bad83 100644
--- a/gpu/command_buffer/client/cmd_buffer_helper.h
+++ b/gpu/command_buffer/client/cmd_buffer_helper.h
@@ -7,9 +7,11 @@
 #ifndef GPU_COMMAND_BUFFER_CLIENT_CMD_BUFFER_HELPER_H_
 #define GPU_COMMAND_BUFFER_CLIENT_CMD_BUFFER_HELPER_H_
 
+#include <list>

[piman, 2014/02/07 22:58:20]

nit: you don't need this.

 #include <string.h>
 #include <time.h>
 
+#include "base/bind.h"

[piman, 2014/02/07 22:58:20]

nit: or this

 #include "gpu/command_buffer/common/cmd_buffer_common.h"
 #include "gpu/command_buffer/common/command_buffer.h"
 #include "gpu/command_buffer/common/constants.h"
@@ -83,6 +85,15 @@ class GPU_EXPORT CommandBufferHelper {
   //   shutdown.
   int32 InsertToken();
 
+  // Returns true if the token has passed.
+  // Parameters:
+  //   the value of the token to check whether it has passed
+  bool HasTokenPassed(int32 token) const {
+    if (token > token_)
+      return true;  // we wrapped
+    return last_token_read() >= token;
+  }
+
   // Waits until the token of a particular value has passed through the command
   // stream (i.e. commands inserted before that token have been executed).
   // NOTE: This will call Flush if it needs to block.