cc: Partial tile update for one-copy raster.

content/browser/gpu/compositor_util.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 "content/browser/gpu/compositor_util.h"
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 250 matching lines @@
   // synchronous, which depends on tiles being ready to draw when raster is
   // complete.  Therefore, it must use one of zero copy, software raster, or
   // GPU raster. So we force zero-copy on for the case where software/GPU raster
   // is not used.
   // TODO(reveman): One-copy can work with sync compositing: crbug.com/490295.
   if (command_line.HasSwitch(switches::kDisableThreadedCompositing))
     return true;
   return command_line.HasSwitch(switches::kEnableZeroCopy);
 }
 
+bool HavePersistentGpuMemoryBuffers() {
+  // We don't need to support this for ZeroCopy as it can't do anything with it
+  // yet.
+  if (IsZeroCopyUploadEnabled())
+    return false;
+  const base::CommandLine& command_line =
+      *base::CommandLine::ForCurrentProcess();
+  if (command_line.HasSwitch(switches::kEnableNativeGpuMemoryBuffers)) {
+    // TODO(reveman): Need native support for this. crbug.com/489438
+    return false;
+  }
+  return true;
+}

[reveman, 2015/05/22 17:15:13]

How about we land the initial version of this with this function just returning
false and then we turn it on in a follow up patch?

[danakj, 2015/05/26 19:02:52]

Sure, if you like. That'll make reverts smaller.

[danakj, 2015/05/26 23:37:34]

Done.

+
 bool IsGpuRasterizationEnabled() {
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
 
   if (!IsImplSidePaintingEnabled())
     return false;
 
   if (command_line.HasSwitch(switches::kDisableGpuRasterization))
     return false;
   else if (command_line.HasSwitch(switches::kEnableGpuRasterization))
@@ skipping 161 matching lines @@
     }
   }
   return problem_list;
 }
 
 std::vector<std::string> GetDriverBugWorkarounds() {
   return GpuDataManagerImpl::GetInstance()->GetDriverBugWorkarounds();
 }
 
 }  // namespace content