gpu: GPU service scheduler.

gpu/command_buffer/common/scheduling_priority.h

Index: gpu/command_buffer/common/scheduling_priority.h
diff --git a/gpu/command_buffer/common/scheduling_priority.h b/gpu/command_buffer/common/scheduling_priority.h
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index 0000000000000000000000000000000000000000..ca93809f60828d21ea3823d31ebdff5ea68673c7
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+++ b/gpu/command_buffer/common/scheduling_priority.h
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+// Copyright 2017 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.
+
+#ifndef GPU_COMMAND_BUFFER_COMMON_SCHEDULING_PRIORITY_H_
+#define GPU_COMMAND_BUFFER_COMMON_SCHEDULING_PRIORITY_H_
+
+#include "gpu/gpu_export.h"
+
+namespace gpu {
+
+enum class SchedulingPriority {
+  // The Highest and High priorities can be used by priveleged clients only.
+  // This priority should be used for UI contexts.
+  kHighest,
+  // This priority is used by the scheduler for prioritizing contexts which have
+  // outstanding sync token waits.
+  kHigh,
+  // The following priorities can be used on unprivileged clients.
+  // This priority should be used as the default priority for all contexts.
+  kNormal,
+  kLow,
+  // This priority should be used for worker contexts.
+  kLowest,
+  kLast = kLowest
+};
+
+GPU_EXPORT const char* SchedulingPriorityToString(SchedulingPriority priority);
+
+}  // namespace gpu
+
+#endif  // GPU_COMMAND_BUFFER_COMMON_SCHEDULING_PRIORITY_H_