diff options
Diffstat (limited to 'win/tclWinTime.c')
| -rw-r--r-- | win/tclWinTime.c | 38 |
1 files changed, 21 insertions, 17 deletions
diff --git a/win/tclWinTime.c b/win/tclWinTime.c index 1204ec7..e4a6a8a 100644 --- a/win/tclWinTime.c +++ b/win/tclWinTime.c @@ -120,9 +120,10 @@ static TimeInfo timeInfo = { */ static struct { int initialized; /* 1 if initialized, 0 otherwise */ - int perfCounter; /* 1 if performance counter usable for wide clicks */ + int perfCounter; /* 1 if performance counter usable for wide + * clicks */ double microsecsScale; /* Denominator scale between clock / microsecs */ -} wideClick = {0, 0.0}; +} wideClick = {0, 0, 0.0}; /* @@ -257,7 +258,7 @@ TclpGetWideClicks(void) /* * The frequency of the performance counter is fixed at system boot and - * is consistent across all processors. Therefore, the frequency need + * is consistent across all processors. Therefore, the frequency need * only be queried upon application initialization. */ if (QueryPerformanceFrequency(&perfCounterFreq)) { @@ -268,7 +269,7 @@ TclpGetWideClicks(void) wideClick.perfCounter = 0; wideClick.microsecsScale = 1; } - + wideClick.initialized = 1; } if (wideClick.perfCounter) { @@ -289,7 +290,7 @@ TclpGetWideClicks(void) * * TclpWideClickInMicrosec -- * - * This procedure return scale to convert wide click values from the + * This procedure return scale to convert wide click values from the * TclpGetWideClicks native resolution to microsecond resolution * and back. * @@ -328,7 +329,7 @@ TclpWideClickInMicrosec(void) *---------------------------------------------------------------------- */ -Tcl_WideInt +Tcl_WideInt TclpGetMicroseconds(void) { Tcl_WideInt usecSincePosixEpoch; @@ -476,7 +477,7 @@ NativeCalc100NsTicks( LONGLONG curCounterFreq, LONGLONG curCounter ) { - return fileTimeLastCall + + return fileTimeLastCall + ((curCounter - perfCounterLastCall) * 10000000 / curCounterFreq); } @@ -493,7 +494,6 @@ NativeGetMicroseconds(void) if (!timeInfo.initialized) { TclpInitLock(); if (!timeInfo.initialized) { - timeInfo.posixEpoch.LowPart = 0xD53E8000; timeInfo.posixEpoch.HighPart = 0x019DB1DE; @@ -624,8 +624,12 @@ NativeGetMicroseconds(void) /* * If calibration cycle occurred after we get curCounter */ + if (curCounter.QuadPart <= perfCounterLastCall) { - /* Calibrated file-time is saved from posix in 100-ns ticks */ + /* + * Calibrated file-time is saved from posix in 100-ns ticks + */ + return fileTimeLastCall / 10; } @@ -1127,7 +1131,6 @@ CalibrationThread( UpdateTimeEachSecond(); } - /* lint */ return (DWORD) 0; } @@ -1158,7 +1161,8 @@ UpdateTimeEachSecond(void) /* Current value returned from * QueryPerformanceCounter. */ FILETIME curSysTime; /* Current system time. */ - static LARGE_INTEGER lastFileTime; /* File time of the previous calibration */ + static LARGE_INTEGER lastFileTime; + /* File time of the previous calibration */ LARGE_INTEGER curFileTime; /* File time at the time this callback was * scheduled. */ Tcl_WideInt estFreq; /* Estimated perf counter frequency. */ @@ -1186,7 +1190,7 @@ UpdateTimeEachSecond(void) return; } QueryPerformanceCounter(&curPerfCounter); - + lastFileTime.QuadPart = curFileTime.QuadPart; /* @@ -1254,7 +1258,7 @@ UpdateTimeEachSecond(void) /* calculate new frequency and estimate drift to the next second */ vt1 = 20000000 + curFileTime.QuadPart; driftFreq = (estFreq * 20000000 / (vt1 - vt0)); - /* + /* * Avoid too large drifts (only half of the current difference), * that allows also be more accurate (aspire to the smallest tdiff), * so then we can prolong calibration interval by tdiff < 100000 @@ -1262,13 +1266,13 @@ UpdateTimeEachSecond(void) driftFreq = timeInfo.curCounterFreq.QuadPart + (driftFreq - timeInfo.curCounterFreq.QuadPart) / 2; - /* + /* * Average between estimated, 2 current and 5 drifted frequencies, * (do the soft drifting as possible) */ estFreq = (estFreq + 2 * timeInfo.curCounterFreq.QuadPart + 5 * driftFreq) / 8; } - + /* Avoid too large discrepancy from nominal frequency */ if (estFreq > 1003*timeInfo.nominalFreq.QuadPart/1000) { estFreq = 1003*timeInfo.nominalFreq.QuadPart/1000; @@ -1277,9 +1281,9 @@ UpdateTimeEachSecond(void) estFreq = 997*timeInfo.nominalFreq.QuadPart/1000; vt0 = curFileTime.QuadPart; } else if (vt0 != curFileTime.QuadPart) { - /* + /* * Be sure the clock ticks never backwards (avoid it by negative drifting) - * just compare native time (in 100-ns) before and hereafter using + * just compare native time (in 100-ns) before and hereafter using * new calibrated values) and do a small adjustment (short time freeze) */ LARGE_INTEGER newPerfCounter; |