Make command buffer commands and immediate data volatile

gpu/command_buffer/service/cmd_parser.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file contains the command parser class.
 
 #ifndef GPU_COMMAND_BUFFER_SERVICE_CMD_PARSER_H_
 #define GPU_COMMAND_BUFFER_SERVICE_CMD_PARSER_H_
 
 #include <stddef.h>
@@ skipping 50 matching lines @@
   // Processes one command, updating the get pointer. This will return an error
   // if there are no commands in the buffer.
   error::Error ProcessCommands(int num_commands);
 
   // Processes all commands until get == put.
   error::Error ProcessAllCommands();
 
  private:
   CommandBufferOffset get_;
   CommandBufferOffset put_;
-  CommandBufferEntry* buffer_;
+  volatile CommandBufferEntry* buffer_;
   int32_t entry_count_;
   AsyncAPIInterface* handler_;
 };
 
 // This class defines the interface for an asynchronous API handler, that
 // is responsible for de-multiplexing commands and their arguments.
 class GPU_EXPORT AsyncAPIInterface {
  public:
   AsyncAPIInterface() {}
   virtual ~AsyncAPIInterface() {}
 
   // Executes a single command.
   // Parameters:
   //    command: the command index.
   //    arg_count: the number of CommandBufferEntry arguments.
   //    cmd_data: the command data.
   // Returns:
   //   error::kNoError if no error was found, one of
   //   error::Error otherwise.
-  virtual error::Error DoCommand(
-      unsigned int command,
-      unsigned int arg_count,
-      const void* cmd_data) = 0;
+  virtual error::Error DoCommand(unsigned int command,
+                                 unsigned int arg_count,
+                                 const volatile void* cmd_data) = 0;
 
   // Executes multiple commands.
   // Parameters:
   //    num_commands: maximum number of commands to execute from buffer.
   //    buffer: pointer to first command entry to process.
   //    num_entries: number of sequential command buffer entries in buffer.
   //    entries_processed: if not 0, is set to the number of entries processed.
   virtual error::Error DoCommands(unsigned int num_commands,
-                                  const void* buffer,
+                                  const volatile void* buffer,
                                   int num_entries,
                                   int* entries_processed);
 
   // Returns a name for a command. Useful for logging / debuging.
   virtual const char* GetCommandName(unsigned int command_id) const = 0;
 };
 
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_CMD_PARSER_H_