cc/trees/latency_info_swap_promise_monitor.cc

// Copyright 2013 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 "cc/trees/latency_info_swap_promise_monitor.h"

#include <stdint.h>

#include "base/threading/platform_thread.h"
#include "cc/output/latency_info_swap_promise.h"
#include "cc/trees/layer_tree_host.h"
#include "cc/trees/layer_tree_host_impl.h"
#include "cc/trees/layer_tree_impl.h"

namespace {

bool AddRenderingScheduledComponent(ui::LatencyInfo* latency_info,
                                    bool on_main) {
  ui::LatencyComponentType type =
      on_main ? ui::INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_MAIN_COMPONENT
              : ui::INPUT_EVENT_LATENCY_RENDERING_SCHEDULED_IMPL_COMPONENT;
  if (latency_info->FindLatency(type, 0, nullptr))
    return false;
  latency_info->AddLatencyNumber(type, 0, 0);
  return true;
}

bool AddForwardingScrollUpdateToMainComponent(ui::LatencyInfo* latency_info) {
  if (latency_info->FindLatency(
          ui::INPUT_EVENT_LATENCY_FORWARD_SCROLL_UPDATE_TO_MAIN_COMPONENT, 0,
          nullptr))
    return false;
  latency_info->AddLatencyNumber(
      ui::INPUT_EVENT_LATENCY_FORWARD_SCROLL_UPDATE_TO_MAIN_COMPONENT, 0,
      latency_info->trace_id());
  return true;
}

}  // namespace

namespace cc {

LatencyInfoSwapPromiseMonitor::LatencyInfoSwapPromiseMonitor(
    ui::LatencyInfo* latency,
    LayerTreeHost* layer_tree_host,
    LayerTreeHostImpl* layer_tree_host_impl)
    : SwapPromiseMonitor(layer_tree_host, layer_tree_host_impl),
      latency_(latency) {
}

LatencyInfoSwapPromiseMonitor::~LatencyInfoSwapPromiseMonitor() {
}

void LatencyInfoSwapPromiseMonitor::OnSetNeedsCommitOnMain() {
  if (AddRenderingScheduledComponent(latency_, true /* on_main */)) {
    scoped_ptr<SwapPromise> swap_promise(new LatencyInfoSwapPromise(*latency_));
    layer_tree_host_->QueueSwapPromise(std::move(swap_promise));
  }
}

void LatencyInfoSwapPromiseMonitor::OnSetNeedsRedrawOnImpl() {
  if (AddRenderingScheduledComponent(latency_, false /* on_main */)) {
    scoped_ptr<SwapPromise> swap_promise(new LatencyInfoSwapPromise(*latency_));
    // Queue a pinned swap promise on the active tree. This will allow
    // measurement of the time to the next SwapBuffers(). The swap
    // promise is pinned so that it is not interrupted by new incoming
    // activations (which would otherwise break the swap promise).
    layer_tree_host_impl_->active_tree()->QueuePinnedSwapPromise(
        std::move(swap_promise));
  }
}

void LatencyInfoSwapPromiseMonitor::OnForwardScrollUpdateToMainThreadOnImpl() {
  if (AddForwardingScrollUpdateToMainComponent(latency_)) {
    int64_t new_sequence_number = 0;
    for (ui::LatencyInfo::LatencyMap::const_iterator it =
             latency_->latency_components().begin();
         it != latency_->latency_components().end(); ++it) {
      if (it->first.first == ui::INPUT_EVENT_LATENCY_BEGIN_RWH_COMPONENT) {
        new_sequence_number =
            ((static_cast<int64_t>(base::PlatformThread::CurrentId()) << 32) ^
             (reinterpret_cast<uint64_t>(this) << 32)) |
            (it->second.sequence_number & 0xffffffff);
        if (new_sequence_number == it->second.sequence_number)
          return;
        break;
      }
    }
    if (!new_sequence_number)
      return;
    ui::LatencyInfo new_latency;
    new_latency.AddLatencyNumberWithTraceName(
        ui::LATENCY_BEGIN_SCROLL_LISTENER_UPDATE_MAIN_COMPONENT, 0,
        new_sequence_number, "ScrollUpdate");
    new_latency.CopyLatencyFrom(
        *latency_,
        ui::INPUT_EVENT_LATENCY_FORWARD_SCROLL_UPDATE_TO_MAIN_COMPONENT);
    scoped_ptr<SwapPromise> swap_promise(
        new LatencyInfoSwapPromise(new_latency));
    layer_tree_host_impl_->QueueSwapPromiseForMainThreadScrollUpdate(
        std::move(swap_promise));
  }
}

}  // namespace cc