From 5e2ce035109d8f3659ac0a21c1567a37b3811942 Mon Sep 17 00:00:00 2001 From: Thiago Macieira Date: Sun, 14 Nov 2021 14:00:23 -0800 Subject: QEventDispatcherWin32: use SetCoalescableTimer for (Very)Coarse timers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The tolerance can be set per timer, unlike on Linux. Fixes: QTBUG-98316 Change-Id: I5e52dc5b093c43a3b678fffd16b788a30bcb9574 Reviewed-by: Mårten Nordheim --- src/corelib/kernel/qeventdispatcher_win.cpp | 48 ++++++++++++++++++++++++----- 1 file changed, 41 insertions(+), 7 deletions(-) diff --git a/src/corelib/kernel/qeventdispatcher_win.cpp b/src/corelib/kernel/qeventdispatcher_win.cpp index c1e7ddfdf9..f5183b4a90 100644 --- a/src/corelib/kernel/qeventdispatcher_win.cpp +++ b/src/corelib/kernel/qeventdispatcher_win.cpp @@ -336,15 +336,47 @@ static HWND qt_create_internal_window(const QEventDispatcherWin32 *eventDispatch return wnd; } -static void calculateNextTimeout(WinTimerInfo *t, quint64 currentTime) +static ULONG calculateNextTimeout(WinTimerInfo *t, quint64 currentTime) { uint interval = t->interval; - if ((interval >= 20000u && t->timerType != Qt::PreciseTimer) || t->timerType == Qt::VeryCoarseTimer) { - // round the interval, VeryCoarseTimers only have full second accuracy - interval = ((interval + 500)) / 1000 * 1000; + ULONG tolerance = TIMERV_DEFAULT_COALESCING; + switch (t->timerType) { + case Qt::PreciseTimer: + // high precision timer is based on millisecond precision + // so no adjustment is necessary + break; + + case Qt::CoarseTimer: + // this timer has up to 5% coarseness + // so our boundaries are 20 ms and 20 s + // below 20 ms, 5% inaccuracy is below 1 ms, so we convert to high precision + // above 20 s, 5% inaccuracy is above 1 s, so we convert to VeryCoarseTimer + if (interval >= 20000) { + t->timerType = Qt::VeryCoarseTimer; + } else if (interval <= 20) { + // no adjustment necessary + t->timerType = Qt::PreciseTimer; + break; + } else { + tolerance = interval / 20; + break; + } + Q_FALLTHROUGH(); + case Qt::VeryCoarseTimer: + // the very coarse timer is based on full second precision, + // so we round to closest second (but never to zero) + tolerance = 1000; + if (interval < 1000) + interval = 1000; + else + interval = (interval + 500) / 1000 * 1000; + currentTime = currentTime / 1000 * 1000; + break; } + t->interval = interval; t->timeout = currentTime + interval; + return tolerance; } void QEventDispatcherWin32Private::registerTimer(WinTimerInfo *t) @@ -354,13 +386,13 @@ void QEventDispatcherWin32Private::registerTimer(WinTimerInfo *t) Q_Q(QEventDispatcherWin32); bool ok = false; - calculateNextTimeout(t, qt_msectime()); + ULONG tolerance = calculateNextTimeout(t, qt_msectime()); uint interval = t->interval; if (interval == 0u) { // optimization for single-shot-zero-timer QCoreApplication::postEvent(q, new QZeroTimerEvent(t->timerId)); ok = true; - } else if (interval < 20u || t->timerType == Qt::PreciseTimer) { + } else if (tolerance == TIMERV_DEFAULT_COALESCING) { // 3/2016: Although MSDN states timeSetEvent() is deprecated, the function // is still deemed to be the most reliable precision timer. t->fastTimerId = timeSetEvent(interval, 1, qt_fast_timer_proc, DWORD_PTR(t), @@ -370,8 +402,10 @@ void QEventDispatcherWin32Private::registerTimer(WinTimerInfo *t) if (!ok) { // user normal timers for (Very)CoarseTimers, or if no more multimedia timers available - ok = SetTimer(internalHwnd, t->timerId, interval, 0); + ok = SetCoalescableTimer(internalHwnd, t->timerId, interval, nullptr, tolerance); } + if (!ok) + ok = SetTimer(internalHwnd, t->timerId, interval, nullptr); if (!ok) qErrnoWarning("QEventDispatcherWin32::registerTimer: Failed to create a timer"); -- cgit v1.2.3