diff options
Diffstat (limited to 'src/corelib/thread/qfutureinterface.cpp')
| -rw-r--r-- | src/corelib/thread/qfutureinterface.cpp | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/src/corelib/thread/qfutureinterface.cpp b/src/corelib/thread/qfutureinterface.cpp index 05482c40c21..1785815cf37 100644 --- a/src/corelib/thread/qfutureinterface.cpp +++ b/src/corelib/thread/qfutureinterface.cpp @@ -259,6 +259,37 @@ void QFutureInterfaceBase::waitForResume() d->pausedWaitCondition.wait(&d->m_mutex); } +void QFutureInterfaceBase::suspendIfRequested() +{ + const auto canSuspend = [] (int state) { + // can suspend only if 1) in any suspend-related state; 2) not canceled + return (state & suspendingOrSuspended) && !(state & Canceled); + }; + + // return early if possible to avoid taking the mutex lock. + { + const int state = d->state.loadRelaxed(); + if (!canSuspend(state)) + return; + } + + QMutexLocker lock(&d->m_mutex); + const int state = d->state.loadRelaxed(); + if (!canSuspend(state)) + return; + + // Note: expecting that Suspending and Suspended are mutually exclusive + if (!(state & Suspended)) { + // switch state in case this is the first invocation + switch_from_to(d->state, Suspending, Suspended); + d->sendCallOut(QFutureCallOutEvent(QFutureCallOutEvent::Suspended)); + } + + // decrease active thread count since this thread will wait. + const ThreadPoolThreadReleaser releaser(d->pool()); + d->pausedWaitCondition.wait(&d->m_mutex); +} + int QFutureInterfaceBase::progressValue() const { const QMutexLocker lock(&d->m_mutex); @@ -361,6 +392,11 @@ bool QFutureInterfaceBase::queryState(State state) const return d->state.loadRelaxed() & state; } +int QFutureInterfaceBase::loadState() const +{ + return d->state.loadRelaxed(); +} + void QFutureInterfaceBase::waitForResult(int resultIndex) { d->m_exceptionStore.throwPossibleException(); |