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() ? base::TimeTicks::ThreadNow()
  15                                                  : base::TimeTicks::Now();
  16 }
  17
  18 }  // namespace
  19
  20 LapTimer::LapTimer(int warmup_laps,
  21                    base::TimeDelta time_limit,
  22                    int check_interval)
  23     : warmup_laps_(warmup_laps),
  24       remaining_warmups_(0),
  25       remaining_no_check_laps_(0),
  26       time_limit_(time_limit),
  27       check_interval_(check_interval) {
  28   DCHECK_GT(check_interval, 0);
  29   Reset();
  30 }
  31
  32 void LapTimer::Reset() {
  33   accumulator_ = base::TimeDelta();
  34   num_laps_ = 0;
  35   remaining_warmups_ = warmup_laps_;
  36   remaining_no_check_laps_ = check_interval_;
  37   Start();
  38 }
  39
  40 void LapTimer::Start() {
  41   start_time_ = Now();
  42 }
  43
  44 bool LapTimer::IsWarmedUp() { return remaining_warmups_ <= 0; }
  45
  46 void LapTimer::NextLap() {
  47   if (!IsWarmedUp()) {
  48     --remaining_warmups_;
  49     if (IsWarmedUp()) {
  50       Start();
  51     }
  52     return;
  53   }
  54   ++num_laps_;
  55   --remaining_no_check_laps_;
  56   if (!remaining_no_check_laps_) {
  57     base::TimeTicks now = Now();
  58     accumulator_ += now - start_time_;
  59     start_time_ = now;
  60     remaining_no_check_laps_ = check_interval_;
  61   }
  62 }
  63
  64 bool LapTimer::HasTimeLimitExpired() { return accumulator_ >= time_limit_; }
  65
  66 bool LapTimer::HasTimedAllLaps() { return !(num_laps_ % check_interval_); }
  67
  68 float LapTimer::MsPerLap() {
  69   DCHECK(HasTimedAllLaps());
  70   return accumulator_.InMillisecondsF() / num_laps_;
  71 }
  72
  73 float LapTimer::LapsPerSecond() {
  74   DCHECK(HasTimedAllLaps());
  75   return num_laps_ / accumulator_.InSecondsF();
  76 }
  77
  78 int LapTimer::NumLaps() { return num_laps_; }
  79
  80 }  // namespace cc