From 66b356265118dd1246757cc052d4c3a416af707c Mon Sep 17 00:00:00 2001 From: Volker Hilsheimer Date: Fri, 28 Feb 2020 12:33:35 +0100 Subject: Try again to make QDeadlineTimer test robust against context switches Instead of comparing to absolute values, compare the result from QDeadlineTimer with the reference clock types from std::chrono. Pass the test as long as we are within 10% of that reference. In addition, handle the case where QTest::qSleep sleeps for more than 10% longer or shorter than what is requested, and if so, abort the test. Change-Id: If8b77aea55a8c5c53e96427b2fff2f78281d0f82 Reviewed-by: Lars Knoll (cherry picked from commit 4a1de178c9cc891560f38d64d89074799b0fa0e1) Reviewed-by: Liang Qi --- .../kernel/qdeadlinetimer/tst_qdeadlinetimer.cpp | 50 +++++++++++++++------- 1 file changed, 34 insertions(+), 16 deletions(-) (limited to 'tests') diff --git a/tests/auto/corelib/kernel/qdeadlinetimer/tst_qdeadlinetimer.cpp b/tests/auto/corelib/kernel/qdeadlinetimer/tst_qdeadlinetimer.cpp index 0a06ed03cf..984a0ef885 100644 --- a/tests/auto/corelib/kernel/qdeadlinetimer/tst_qdeadlinetimer.cpp +++ b/tests/auto/corelib/kernel/qdeadlinetimer/tst_qdeadlinetimer.cpp @@ -573,12 +573,32 @@ void tst_QDeadlineTimer::stdchrono() QCOMPARE(deadline.remainingTimeAsDuration(), nanoseconds::zero()); + /* + Call QTest::qSleep, and return true if the time actually slept is + within \a deviationPercent percent of the requested sleep time. + Otherwise, return false, in which case the test should to abort. + */ + auto sleepHelper = [](int ms, int deviationPercent = 10) -> bool { + auto before = steady_clock::now(); + QTest::qSleep(ms); + auto after = steady_clock::now(); + auto diff = duration_cast(after - before).count(); + bool inRange = qAbs(diff - ms) < ms * deviationPercent/100.0; + if (!inRange) + qWarning() << "sleeping" << diff << "instead of" << ms << inRange; + return inRange; + }; + auto steady_before = steady_clock::now(); auto system_before = system_clock::now(); - QTest::qSleep(minResolution); + if (!sleepHelper(minResolution)) + QSKIP("Slept too long"); auto now = QDeadlineTimer::current(timerType); - QTest::qSleep(minResolution); + auto steady_reference = steady_clock::now(); + auto system_reference = system_clock::now(); + if (!sleepHelper(minResolution)) + QSKIP("Slept too long"); auto sampling_start = steady_clock::now(); auto steady_deadline = now.deadline(); @@ -599,35 +619,33 @@ void tst_QDeadlineTimer::stdchrono() } { - auto diff = duration_cast(steady_after - steady_deadline); - QVERIFY2(diff.count() > minResolution/2, QByteArray::number(qint64(diff.count()))); - QVERIFY2(diff.count() < 3*minResolution/2, QByteArray::number(qint64(diff.count()))); + auto reference = duration_cast(steady_after - steady_reference).count(); + auto diff = duration_cast(steady_after - steady_deadline).count(); + QVERIFY2(diff > reference * 0.9 && diff < reference*1.1, QByteArray::number(qint64(diff))); QDeadlineTimer dt_after(steady_after, timerType); QVERIFY2(now < dt_after, ("now = " + QLocale().toString(now.deadlineNSecs()) + "; after = " + QLocale().toString(dt_after.deadlineNSecs())).toLatin1()); - diff = duration_cast(steady_deadline - steady_before); - QVERIFY2(diff.count() > minResolution/2, QByteArray::number(qint64(diff.count()))); - QVERIFY2(diff.count() < 3*minResolution/2, QByteArray::number(qint64(diff.count()))); + reference = duration_cast(steady_reference - steady_before).count(); + diff = duration_cast(steady_deadline - steady_before).count(); + QVERIFY2(diff > reference * 0.9 && diff < reference*1.1, QByteArray::number(qint64(diff))); QDeadlineTimer dt_before(steady_before, timerType); QVERIFY2(now > dt_before, ("now = " + QLocale().toString(now.deadlineNSecs()) + "; before = " + QLocale().toString(dt_before.deadlineNSecs())).toLatin1()); } { - auto diff = duration_cast(system_after - system_deadline); - QVERIFY2(diff.count() > minResolution/2, QByteArray::number(qint64(diff.count()))); - QVERIFY2(diff.count() < 3*minResolution/2, QByteArray::number(qint64(diff.count()))); - QDeadlineTimer dt_after(system_after, timerType); + auto reference = duration_cast(system_after - system_reference).count(); + auto diff = duration_cast(system_after - system_deadline).count(); + QVERIFY2(diff > reference * 0.9 && diff < reference*1.1, QByteArray::number(qint64(diff))); QDeadlineTimer dt_after(system_after, timerType); QVERIFY2(now < dt_after, ("now = " + QLocale().toString(now.deadlineNSecs()) + "; after = " + QLocale().toString(dt_after.deadlineNSecs())).toLatin1()); - diff = duration_cast(system_deadline - system_before); - QVERIFY2(diff.count() > minResolution/2, QByteArray::number(qint64(diff.count()))); - QVERIFY2(diff.count() < 3*minResolution/2, QByteArray::number(qint64(diff.count()))); - QDeadlineTimer dt_before(system_before, timerType); + reference = duration_cast(system_reference - system_before).count(); + diff = duration_cast(steady_deadline - steady_before).count(); + QVERIFY2(diff > reference * 0.9 && diff < reference*1.1, QByteArray::number(qint64(diff))); QDeadlineTimer dt_before(system_before, timerType); QVERIFY2(now > dt_before, ("now = " + QLocale().toString(now.deadlineNSecs()) + "; before = " + QLocale().toString(dt_before.deadlineNSecs())).toLatin1()); -- cgit v1.2.3