ui/gfx/swap_result.h

// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_GFX_SWAP_RESULT_H_
#define UI_GFX_SWAP_RESULT_H_

#include <memory>

#include "base/component_export.h"
#include "base/time/time.h"
#include "ui/gfx/gpu_fence_handle.h"

namespace gfx {

struct CALayerParams;

enum class SwapResult {
  SWAP_ACK,
  SWAP_FAILED,
  // Typically, the Viz thread should decide whether to skip a swap based off
  // the damage. In rare cases, however, the GPU main thread might skip the
  // swap after the Viz thread requests it (e.g. the Viz thread might not know
  // that the buffers are not fully initialized yet). For the purposes of
  // metrics bookkeeping, we label this scenario as SWAP_SKIPPED and treat it
  // much like we do a SWAP_FAILED (e.g. failed PresentationFeedback).
  // TODO(https://crbug.com/1226090): Consider more explicit handling of
  // SWAP_SKIPPED.
  SWAP_SKIPPED,
  SWAP_NAK_RECREATE_BUFFERS,
  // This swap result identifies cases when flipping non-simple overlay planes
  // fails.
  SWAP_NON_SIMPLE_OVERLAYS_FAILED,
  SWAP_RESULT_LAST = SWAP_NON_SIMPLE_OVERLAYS_FAILED,
};

struct SwapTimings {
  // When the GPU service first started processing the SwapBuffers request.
  base::TimeTicks swap_start;

  // On most platforms, this is when the GPU service finished processing the
  // SwapBuffers request. On ChromeOS, this corresponds to the present time.
  // TODO(brianderson): Differentiate the concepts without introducing
  // dicontinuities in associated UMA data.
  base::TimeTicks swap_end;

  // When Display Compositor thread scheduled work to GPU Thread. For
  // SkiaRenderer it's PostTask time for FinishPaintRenderPass or SwapBuffers
  // whichever comes first.
  base::TimeTicks viz_scheduled_draw;

  // When GPU thread started draw submitted by Display Compositor thread. For
  // SkiaRenderer it's FinishPaintRenderPass/SwapBuffers.
  base::TimeTicks gpu_started_draw;