cc/debug/lap_timer.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "cc/debug/lap_timer.h"
   6
   7 #include "base/logging.h"
   8
   9 namespace cc {
  10
  11 namespace {
  12
  13 base::TimeTicks Now() {
  14   return base::TimeTicks::IsThreadNowSupported()
  15              ? base::TimeTicks::ThreadNow()
  16              : base::TimeTicks::HighResNow();
  17 }
  18
  19 }  // namespace
  20
  21 LapTimer::LapTimer(int warmup_laps,
  22                    base::TimeDelta time_limit,
  23                    int check_interval)
  24     : warmup_laps_(warmup_laps),
  25       remaining_warmups_(0),
  26       remaining_no_check_laps_(0),
  27       time_limit_(time_limit),
  28       check_interval_(check_interval) {
  29   DCHECK_GT(check_interval, 0);
  30   Reset();
  31 }
  32
  33 void LapTimer::Reset() {
  34   accumulator_ = base::TimeDelta();
  35   num_laps_ = 0;
  36   remaining_warmups_ = warmup_laps_;
  37   remaining_no_check_laps_ = check_interval_;
  38   Start();
  39 }
  40
  41 void LapTimer::Start() {
  42   start_time_ = Now();
  43 }
  44
  45 bool LapTimer::IsWarmedUp() { return remaining_warmups_ <= 0; }
  46
  47 void LapTimer::NextLap() {
  48   if (!IsWarmedUp()) {
  49     --remaining_warmups_;
  50     if (IsWarmedUp()) {
  51       Start();
  52     }
  53     return;
  54   }
  55   ++num_laps_;
  56   --remaining_no_check_laps_;
  57   if (!remaining_no_check_laps_) {
  58     base::TimeTicks now = Now();
  59     accumulator_ += now - start_time_;
  60     start_time_ = now;
  61     remaining_no_check_laps_ = check_interval_;
  62   }
  63 }
  64
  65 bool LapTimer::HasTimeLimitExpired() { return accumulator_ >= time_limit_; }
  66
  67 bool LapTimer::HasTimedAllLaps() { return !(num_laps_ % check_interval_); }
  68
  69 float LapTimer::MsPerLap() {
  70   DCHECK(HasTimedAllLaps());
  71   return accumulator_.InMillisecondsF() / num_laps_;
  72 }
  73
  74 float LapTimer::LapsPerSecond() {
  75   DCHECK(HasTimedAllLaps());
  76   return num_laps_ / accumulator_.InSecondsF();
  77 }
  78
  79 int LapTimer::NumLaps() { return num_laps_; }
  80
  81 }  // namespace cc