This is extremely useful, since the most common action after a failed
compare-and-swap is to loop around, trying again with the current
value as found in memory.
Code currently written as:
do {
Type value = atomic.load();
...
} while (!atomic.testAndSetRelaxed(value, desired));
Becomes:
Type value = atomic.load();
do {
...
} while (!atomic.testAndSetRelaxed(value, desired, value));
In most CPU architectures, the value that was found in memory is known
to the compare-and-swap code, so this is more efficient than the
previous code. In architectures where the value is not known, the new
code is no worse than before.
The implementation sometimes modified an existing function, sometimes
it added a new one, depending on whether more registers were needed in
the assembly (like ARMv6-7), the code became more complex (ARMv5), the
optimizer failed (C++11), or it was just plain equivalent (MIPS).
Change-Id: I7d6d200ea9746ec8978a0c1e1969dbc3580b9285
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
This simplifies the code a lot and avoids silly mistakes where a
specific integer type is missing (such as char16_t).
Change-Id: Id91dfd1919e783e0a9af7bfa093ca560a01b22d1
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
For the conflicts in msvc_nmake.cpp the ifdefs are extended since we
need to support windows phone in the target branch while it is not there
in the current stable branch (as of Qt 5.2).
Conflicts:
configure
qmake/generators/win32/msvc_nmake.cpp
src/3rdparty/angle/src/libEGL/Surface.cpp
src/angle/src/common/common.pri
src/corelib/global/qglobal.h
src/corelib/io/qstandardpaths.cpp
src/plugins/platforms/qnx/qqnxintegration.cpp
src/plugins/platforms/qnx/qqnxscreeneventhandler.h
src/plugins/platforms/xcb/qglxintegration.h
src/widgets/kernel/win.pri
tests/auto/corelib/thread/qreadwritelock/tst_qreadwritelock.cpp
tests/auto/corelib/tools/qdatetime/tst_qdatetime.cpp
tests/auto/gui/text/qtextdocument/tst_qtextdocument.cpp
tools/configure/configureapp.cpp
Change-Id: I00b579eefebaf61d26ab9b00046d2b5bd5958812
Tweak a handful of tests which didn't compile on this platform.
Change-Id: I208d9eb289dfb226746c6d0163c3ea752485033b
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>
The current synchronization mechanism was racy: decrementing waitingThreads
and then hoping that the wakeOne will wake a thread before its expiry
timeout happens. In other words, on timeout, a just-assigned task would
never run. And then no other task would run, if maxThreadCount is reached.
Fixed by using a queue of waiting threads (rather than just a count), and by
moving the wait condition into the thread itself, so we know precisely
which one we're waking up, and we can remove it from the set of waiting threads
before waking it up, and therefore it can determine on wakeup whether it
has work to do (caller removed it from the queue) or it expired (it's still
in the queue). This is reliable, whereas the return value from QWaitCondition::wait
isn't reliable, when the main thread has already decided that this thread
has work to do.
Task-number: QTBUG-3786
Change-Id: I1eac5d6c309daed7f483ac7a8074297bfda6ee32
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Change-Id: Ib1047731667ba8a7b9db2f62924eb42a6b85b4fd
Reviewed-by: Andrew Knight <andrew.knight@digia.com>
Reviewed-by: Maurice Kalinowski <maurice.kalinowski@digia.com>
Change-Id: I88d98421978e0f5c55af8647f3f74c265b45bd37
Reviewed-by: Andrew Knight <andrew.knight@digia.com>
Reviewed-by: Maurice Kalinowski <maurice.kalinowski@digia.com>
- Remove irrelevant test subdirs via .pro files
- Follow WinCE codepaths where applicable
- Replace unsupported Win32 APIs with WinRT equivalents
This does not aim to fix any failures in the tests themselves; it only
makes them compile.
Change-Id: Ia82bc0cc402891f8f6238d4c261ee9152b51be80
Reviewed-by: Maurice Kalinowski <maurice.kalinowski@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Fixes the obvious race between the test of 'release' in the thread
and the setting of 'release' in the test function.
Change-Id: I92df52d7b18e8154f17229a3dbd4a0e58f4a3b5b
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
The code uses a QSignalSpy to check whether the thread started,
but the signal emission (and subsequent appending to the spy) and
the check for spy.count() before the final thr.wait() are not
synchronized:
The signal emission happens-after the thr.start() and -before the
final thr.wait(). Likewise, the spy.count() happens-after thr.start()
and -before thr.wait(), but neither one happens-before the other.
Thus, there is a data race.
The wait(200) between thr.start() and mutex.unlock() doesn't help,
either, because we check only that it doesn't return true, iow, we
check that it timed out. But it will happily do that if the thread
has not yet started executing, so there's no happens-before relation
to be had via that avenue, either.
I first fixed by moving the spy.count() check to after thr.wait().
In that case:
signal emission happens-before thread finishing
happens-before thr.wait() returning
happens-before spy.count()
so no race.
Arguably, that makes the check rather useless, so I decided to remove
it completely.
Change-Id: I6bb47c4114961ee6e9251cfebeb4b7794ba674a9
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
To ease interruption of long running tasks, a new method
QThread::setInterruptionRequested() can be called.
The task can check QThread::isInterruptionRequested()
and act upon it by stopping itself.
These methods are designed to replace the use of a global variable
and other hacky ways to stop a task running in another thread.
Change-Id: I17622dd60d2262078210e7e4294ad6c53a6dc179
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(dacf9961da)
In order to see 2 active threads, we must check activeThreadCount() before
the runnable finishes.
Change-Id: I1a48b41e0c1fd81a65d915b9bd1e741ff267ed2b
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
QTBUG-21051 has a testcase where activeThreadCount() could actually
end up at -1 (converted to an autotest in this commit).
The reason was: start() calls tryStart() which returns false due to
too many active threads (reserveThread() causes this), so it calls
enqueueTask() - which actually wakes up the waiting thread, but
it didn't decrement the number of waiting threads.
Note that tryStart() is "if I can grab a waiting thread, enqueue task and wake it"
while start(), in case tryStart() fails, wants to "enqueue, and then if I can grab
a waiting thread, wake it". This is why enqueue shouldn't wake; waking must happen
only if we can grab a thread (d->waitingThreads > 0).
Task-number: QTBUG-21051
Change-Id: I3d98337103031c9bdf0bf365295f245be0c66aa7
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
QThreadPool::clear() method removes all queued QRunnable.
When a large number of long-running tasks are queud in a
QThreadPool its destruction, which calls waitForDone(), can
be quite long.
QThreadPool:clear() removes (and deletes when appropriate)
all QRunnable that have yet to be started from the queue
enabling a faster interruption.
Change-Id: Ie5d6028ad3cfe7e439d1db068c8d0936ff818db9
Reviewed-by: David Faure <david.faure@kdab.com>
The optimisation done in cbaf52b099 for Qt
5.0 got the order wrong of the comparison. The queue must be sorted in
decreasing priority order. But since higher numbers mean higher
priority, that means the queue must be sorted in decreasing priority
number order.
Task-number: QTBUG-29163
Change-Id: Iaf3424b9bb445bf5c71518927f37253cead454f3
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Remove all trailing whitespace from the following list of files:
*.cpp *.h *.conf *.qdoc *.pro *.pri *.mm *.rc *.pl *.qps *.xpm *.txt *README
excluding 3rdparty, test-data and auto generated code.
Note A): the only non 3rdparty c++-files that still
have trailing whitespace after this change are:
* src/corelib/codecs/cp949codetbl_p.h
* src/corelib/codecs/qjpunicode.cpp
* src/corelib/codecs/qbig5codec.cpp
* src/corelib/xml/qxmlstream_p.h
* src/tools/qdoc/qmlparser/qqmljsgrammar.cpp
* src/tools/uic/ui4.cpp
* tests/auto/other/qtokenautomaton/tokenizers/*
* tests/benchmarks/corelib/tools/qstring/data.cpp
* util/lexgen/tokenizer.cpp
Note B): in about 30 files some overlapping 'leading tab' and
'TAB character in non-leading whitespace' issues have been fixed
to make the sanity bot happy. Plus some general ws-fixes here
and there as asked for during review.
Change-Id: Ia713113c34d82442d6ce4d93d8b1cf545075d11d
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
The macro was made empty in ba3dc5f3b5
and is no longer necessary or used.
Discussed-on: http://lists.qt-project.org/pipermail/development/2013-January/009284.html
Change-Id: Id2bb2e2cabde059305d4af5f12593344ba30f001
Reviewed-by: Laszlo Papp <lpapp@kde.org>
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>
Qt 4.8 shows frequent crashes in runMultiple apparently caused
by the QMutex construction in the free functions by different
threads. Use a common QMutex class member instead.
Change-Id: I851d4e2d3637a7b4f404ed843f5360c10caa21f5
Reviewed-by: Mitch Curtis <mitch.curtis@digia.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
The Linux futex implementation had a Q_ASSERT for positive values, but
the documentation says that negative values should be interpreted as
infinite (equal to lock()).
Test that too.
Change-Id: I2f96a502d672732781e88e49797756ca9a809121
Reviewed-by: David Faure (KDE) <faure@kde.org>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
The timeout is in millisecond. So we just need to divide by 1000 to get
the number of seconds
Regression introduced in f587e8f4fd
Reported in the comments of QTBUG-24795
Change-Id: Id16e05e7d04d33605860926f7516d14cdefd6a36
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
To avoid leaking when converting a QFuture<T> to a QFuture<void> we need
to have a separate ref. counter for QFuture<T>. When the last QFuture<T>
goes out of scope, we need to clean out the result data.
Task-number: QTBUG-27224
Change-Id: I965a64a11fffbb191ab979cdd030a9aafd4436c2
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@digia.com>
Normalise all signal/slot signatures in tests/*/corelib,
except in tst_QObject, where they might be test data.
Change-Id: Id4e101f285b1676bb583b0afae06d235e599e24b
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Reviewed-by: Marc Mutz <marc.mutz@kdab.com>
The signal is removed from the API; all references to it are removed
from documentation; the unit test that checks for its emission is
modified to listen for QThread::finished() instead.
The QThreadPrivate::terminated flag is also removed, as it served no
purpose other than to trigger the emission of QThread::terminated()
As discussed at http://lists.qt-project.org/pipermail/development/2012-October/007216.html
the signal is not guaranteed to be emitted after every termination,
rendering it useless.
Change-Id: I7b0c45d7889da0d33875545331606f2208ee56fc
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Instead omit the whole test when Q_OS_WINCE is defined.
Change-Id: Id6f4e65c994115b8bab45f9fbf21dd255d204ea6
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
This class belongs to QThreadPool/QRunnable more than to QtConcurrent, so
move to QtCore, where QThreadPool awaits it.
Change-Id: Ibf20288a986593bf779453427c2dae8db1e1423a
Reviewed-by: Qt Doc Bot <qt_docbot@qt-project.org>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
No compatibility header needed. While this wasn't marked as private API,
it wasn't documented, either.
This is a prerequisite for moving QFuture to QtCore.
Change-Id: I8e986e6e2a22fbe5cf08d0600ec39ae9ae993e20
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Change copyrights and license headers from Nokia to Digia
Change-Id: If1cc974286d29fd01ec6c19dd4719a67f4c3f00e
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: Sergio Ahumada <sergio.ahumada@digia.com>
QElaspedTimer is a lot more efficient.
Change-Id: I66d9514108f800a45181d8960b01a5e7d3fa9e80
Reviewed-by: Qt Doc Bot <qt_docbot@qt-project.org>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>
The test tries to acquire a semaphore that isn't ready, so it will
timeout. The test is working properly.
The only problem is that 10 ms is too strict. For a wide variety of
reasons, especially since the Qt CI system runs multiple tests in
parallel, the program may not run again in that 10 ms window.
Change-Id: Ic0f684895f73646db5f1cc783fe9ef75fb1ab02b
Reviewed-by: Qt Doc Bot <qt_docbot@qt-project.org>
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>
Just to make it clear which two sections go together.
Change-Id: If3724d1c84172a61bdd7931cc567f4b7140d4f8a
Reviewed-by: Jason McDonald <jason.mcdonald@nokia.com>
Reviewed-by: Bradley T. Hughes <bradley.hughes@nokia.com>
Those are regular, integer types, of 16- and 32-bit width,
respectively. C++11's std::atomic supports them, so we should too.
C++11 also supports wchar_t, but since that type's size can change, I
don't feel like support for it in Qt is pressing.
Change-Id: I945b641c91a8a98be82715f878c382dee58ac98b
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
This allows one to write code that depends on these values at
compile-time.
Change-Id: I7d78524ed9c70d4141360496d1d764dcbfa92e62
Reviewed-by: Marc Mutz <marc.mutz@kdab.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Qt 5.0 beta requires changing the default to the 5.0 API, disabling
the deprecated code. However, tests should test (and often do) the
compatibility API too, so turn it back on.
Task-number: QTBUG-25053
Change-Id: I8129c3ef3cb58541c95a32d083850d9e7f768927
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>
This is working, but let's just be sure by adding a testcase.
Change-Id: I8c6b5ded0c7b6c90645dbf70a7ce6c1ba447a284
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>
Reviewed-by: Jason McDonald <jason.mcdonald@nokia.com>
Make test projects declare TEST_HELPER_INSTALLS rather than calling a
function exported by testcase.prf. load(testcase) may be unsafe, as
testcase.prf should be processed after default_post.prf.
Fixes silent disabling of various autotests.
Change-Id: I56b35ffd653a637ad5ab18d64dd1a1edadfac59f
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@nokia.com>
Reviewed-by: Kurt Korbatits <kurt.korbatits@nokia.com>
The use of QWeakPointer for tracking QObject pointers is to be
deprecated.
Change-Id: If460ca7f515db77af24030152f4bd56e1a5fae7c
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
These tests have passed a parallel stress test on all three of Linux,
Mac, Windows. Mark them with CONFIG+=parallel_test to allow CI to run
them in parallel, saving time.
Change-Id: I19fd333c3c645a67374ca998f6c8530dd236b0f8
Reviewed-by: Toby Tomkins <toby.tomkins@nokia.com>
