1berry/qtbase
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

QObjectData: relax accesses to postedEvents

Browse Source 
If one wants to access the event list itself, they have to lock the
postedEventList mutex, so none of these probably need any more ordering
than Relaxed. I've left most of them in Acquire/Release because we don't
have time to reason whether Relaxed suffices (the one exception is a
loadRelaxed() that calls a function that does loadAcquire()).

Amends commit ba6c1d2785ca6d8a8b162abcd9d978ab0c52ea2d.

Pick-to: 6.8
Change-Id: I35810f961b96aaf63d74fffd1eda73b3e059583d
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
This commit is contained in:
Thiago Macieira 2024-11-13 12:56:24 -08:00
parent 083e44318c
commit d7c9619a81
3 changed files with 12 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
src/corelib/kernel/qcoreapplication.cpp
View File

@ -503,7 +503,7 @@ void QCoreApplicationPrivate::cleanupThreadData()
const auto locker = qt_scoped_lock(thisThreadData->postEventList.mutex);
for (const QPostEvent &pe : std::as_const(thisThreadData->postEventList)) {
if (pe.event) {
--pe.receiver->d_func()->postedEvents;
pe.receiver->d_func()->postedEvents.fetchAndSubAcquire(1);
pe.event->m_posted = false;
delete pe.event;
}
@ -1660,7 +1660,7 @@ void QCoreApplication::postEvent(QObject *receiver, QEvent *event, int priority)
QThreadData *data = locker.threadData;
// if this is one of the compressible events, do compression
if (receiver->d_func()->postedEvents
if (receiver->d_func()->postedEvents.loadAcquire()
&& self && self->compressEvent(event, receiver, &data->postEventList)) {
Q_TRACE(QCoreApplication_postEvent_event_compressed, receiver, event);
return;
@ -1673,7 +1673,7 @@ void QCoreApplication::postEvent(QObject *receiver, QEvent *event, int priority)
data->postEventList.addEvent(QPostEvent(receiver, event, priority));
Q_UNUSED(eventDeleter.release());
event->m_posted = true;
++receiver->d_func()->postedEvents;
receiver->d_func()->postedEvents.fetchAndAddRelease(1);
data->canWait = false;
locker.unlock();
@ -1774,7 +1774,8 @@ void QCoreApplicationPrivate::sendPostedEvents(QObject *receiver, int event_type
// events, canWait will be set to false.
data->canWait = (data->postEventList.size() == 0);
if (data->postEventList.size() == 0 || (receiver && !receiver->d_func()->postedEvents)) {
if (data->postEventList.size() == 0
|| (receiver && !receiver->d_func()->postedEvents.loadAcquire())) {
--data->postEventList.recursion;
return;
}
@ -1903,7 +1904,7 @@ void QCoreApplicationPrivate::sendPostedEvents(QObject *receiver, int event_type
QEvent *e = pe.event;
QObject * r = pe.receiver;
--r->d_func()->postedEvents;
r->d_func()->postedEvents.fetchAndSubAcquire(1);
Q_ASSERT(r->d_func()->postedEvents >= 0);
// next, update the data structure so that we're ready
@ -1954,7 +1955,7 @@ void QCoreApplication::removePostedEvents(QObject *receiver, int eventType)
// happen while the event loop is in the middle of posting events,
// and when we get here, we may not have any more posted events
// for this object.
if (receiver && !receiver->d_func()->postedEvents)
if (receiver && !receiver->d_func()->postedEvents.loadAcquire())
return;
//we will collect all the posted events for the QObject
@ -1968,7 +1969,7 @@ void QCoreApplication::removePostedEvents(QObject *receiver, int eventType)
if ((!receiver || pe.receiver == receiver)
&& (pe.event && (eventType == 0 || pe.event->type() == eventType))) {
--pe.receiver->d_func()->postedEvents;
pe.receiver->d_func()->postedEvents.fetchAndSubAcquire(1);
pe.event->m_posted = false;
events.append(pe.event);
const_cast<QPostEvent &>(pe).event = nullptr;
@ -2029,7 +2030,7 @@ void QCoreApplicationPrivate::removePostedEvent(QEvent * event)
pe.receiver->metaObject()->className(),
pe.receiver->objectName().toLocal8Bit().data());
#endif
--pe.receiver->d_func()->postedEvents;
pe.receiver->d_func()->postedEvents.fetchAndSubAcquire(1);
pe.event->m_posted = false;
delete pe.event;
const_cast<QPostEvent &>(pe).event = nullptr;

4
src/corelib/kernel/qobject.cpp
View File

@ -172,7 +172,7 @@ QObjectPrivate::QObjectPrivate(int version)
isDeletingChildren = false; // set by deleteChildren()
sendChildEvents = true; // if we should send ChildAdded and ChildRemoved events to parent
receiveChildEvents = true;
postedEvents = 0;
postedEvents.storeRelaxed(0);
extraData = nullptr;
metaObject = nullptr;
isWindow = false;
@ -200,7 +200,7 @@ QObjectPrivate::~QObjectPrivate()
}
}
if (postedEvents)
if (postedEvents.loadRelaxed())
QCoreApplication::removePostedEvents(q_ptr, 0);
thisThreadData->deref();

2
src/corelib/thread/qthread.cpp
View File

@ -68,7 +68,7 @@ QThreadData::~QThreadData()
for (qsizetype i = 0; i < postEventList.size(); ++i) {
const QPostEvent &pe = postEventList.at(i);
if (pe.event) {
--pe.receiver->d_func()->postedEvents;
pe.receiver->d_func()->postedEvents.fetchAndSubRelaxed(1);
pe.event->m_posted = false;
delete pe.event;
}