gpu: Reuse transfer buffers more aggresively

gpu/command_buffer/client/buffer_tracker.cc

 // 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.
 
 #include "gpu/command_buffer/client/buffer_tracker.h"
 
 #include "gpu/command_buffer/client/cmd_buffer_helper.h"
 #include "gpu/command_buffer/client/mapped_memory.h"
 
 namespace gpu {
@@ skipping 42 matching lines @@
   }
 }
 
 void BufferTracker::FreePendingToken(Buffer* buffer, int32 token) {
   if (buffer->address_)
     mapped_memory_->FreePendingToken(buffer->address_, token);
   buffer->size_ = 0;
   buffer->shm_id_ = 0;
   buffer->shm_offset_ = 0;
   buffer->address_ = NULL;
+  buffer->last_usage_token_ = 0;
 }
 
+void BufferTracker::FreePendingSerial(Buffer* buffer, uint32 serial) {
+  if (buffer->address_)
+    mapped_memory_->FreePendingSerial(buffer->address_, serial);
+  buffer->size_ = 0;
+  buffer->shm_id_ = 0;
+  buffer->shm_offset_ = 0;
+  buffer->address_ = NULL;
+  buffer->last_usage_token_ = 0;
+}
+
+void BufferTracker::Free(Buffer* buffer) {
+  if (buffer->address_)
+    mapped_memory_->Free(buffer->address_);
+
+  buffer->size_ = 0;
+  buffer->shm_id_ = 0;
+  buffer->shm_offset_ = 0;
+  buffer->address_ = NULL;
+  buffer->last_usage_token_ = 0;
+}
 
 }  // namespace gles2
 }  // namespace gpu