diff options
Diffstat (limited to 'base/time_win.cc')
| -rw-r--r-- | base/time_win.cc | 33 |
1 files changed, 24 insertions, 9 deletions
diff --git a/base/time_win.cc b/base/time_win.cc index f44c7f1..d4da0f4 100644 --- a/base/time_win.cc +++ b/base/time_win.cc @@ -98,6 +98,8 @@ void InitializeClock() { // static const int64 Time::kTimeTToMicrosecondsOffset = GG_INT64_C(11644473600000000); +bool Time::high_resolution_timer_enabled_ = false; + // static Time Time::Now() { if (initial_time == 0) @@ -148,18 +150,31 @@ FILETIME Time::ToFileTime() const { } // static -bool Time::UseHighResolutionTimer(bool use) { - // TODO(mbelshe): Make sure that switching the system timer resolution - // doesn't break Timer firing order etc. An example test would be to have - // two threads. One would have a bunch of timers, and another would turn the - // high resolution timer on and off. +void Time::EnableHighResolutionTimer(bool enable) { + // Test for single-threaded access. + static PlatformThreadId my_thread = PlatformThread::CurrentId(); + DCHECK(PlatformThread::CurrentId() == my_thread); + + if (high_resolution_timer_enabled_ == enable) + return; + + high_resolution_timer_enabled_ = enable; +} + +// static +bool Time::ActivateHighResolutionTimer(bool activate) { + if (!high_resolution_timer_enabled_) + return false; + // Using anything other than 1ms makes timers granular + // to that interval. + const int kMinTimerIntervalMs = 1; MMRESULT result; - if (use) - result = timeBeginPeriod(1); + if (activate) + result = timeBeginPeriod(kMinTimerIntervalMs); else - result = timeEndPeriod(1); - return (result == TIMERR_NOERROR); + result = timeEndPeriod(kMinTimerIntervalMs); + return result == TIMERR_NOERROR; } // static |