QMutexPrivate Class Reference

#include <qmutex_p.h>

Inheritance diagram for QMutexPrivate:

Public Types
enum	{ MaximumSpinTimeThreshold = 1000000 }

Public Functions
	QMutexPrivate (QMutex::RecursionMode mode)
bool	wait (int timeout=-1)
void	wakeUp ()
	~QMutexPrivate ()

Public Variables
volatile qint64	averageWaitTime
uint	count
HANDLE	event
volatile qint64	maximumSpinTime
Qt::HANDLE	owner
Public Variables inherited from QMutexData
QAtomicInt	contenders
const uint	recursive: 1
uint	reserved: 31

Additional Inherited Members
Protected Functions inherited from QMutexData
	QMutexData (QMutex::RecursionMode mode)
	~QMutexData ()

Detailed Description

Definition at line 67 of file qmutex_p.h.

Enumerations

anonymous enum

anonymous enum

Enumerator
MaximumSpinTimeThreshold

Definition at line 76 of file qmutex_p.h.

{ MaximumSpinTimeThreshold = 1000000 };

Constructors and Destructors

QMutexPrivate()

QMutexPrivate::QMutexPrivate

(

QMutex::RecursionMode

mode

)

Definition at line 77 of file qmutex_unix.cpp.

    : QMutexData(mode), maximumSpinTime(MaximumSpinTimeThreshold), averageWaitTime(0), owner(0), count(0)
{
#if !defined(Q_OS_LINUX) || defined(QT_LINUXBASE)
    wakeup = false;
    report_error(pthread_mutex_init(&mutex, NULL), "QMutex", "mutex init");
    report_error(pthread_cond_init(&cond, NULL), "QMutex", "cv init");
#endif
}

~QMutexPrivate()

QMutexPrivate::~QMutexPrivate

(

)

Definition at line 87 of file qmutex_unix.cpp.

{
#if !defined(Q_OS_LINUX) || defined(QT_LINUXBASE)
    report_error(pthread_cond_destroy(&cond), "QMutex", "cv destroy");
    report_error(pthread_mutex_destroy(&mutex), "QMutex", "mutex destroy");
#endif
}

Functions

wait()

bool QMutexPrivate::wait

(

int

timeout = -1

)

Definition at line 102 of file qmutex_unix.cpp.

Referenced by QMutex::lock(), QMutex::lockInternal(), and QMutex::tryLock().

{
    struct timespec ts, *pts = 0;
    QElapsedTimer timer;
    if (timeout >= 0) {
        ts.tv_nsec = ((timeout % 1000) * 1000) * 1000;
        ts.tv_sec = (timeout / 1000);
        pts = &ts;
        timer.start();
    }
    while (contenders.fetchAndStoreAcquire(2) > 0) {
        int r = _q_futex(&contenders._q_value, FUTEX_WAIT, 2, pts, 0, 0);
        if (r != 0 && errno == ETIMEDOUT)
            return false;

        if (pts) {
            // recalculate the timeout
            qint64 xtimeout = timeout * 1000 * 1000;
            xtimeout -= timer.nsecsElapsed();
            if (xtimeout < 0) {
                // timer expired after we returned
                return false;
            }

            ts.tv_sec = xtimeout / Q_INT64_C(1000) / 1000 / 1000;
            ts.tv_nsec = xtimeout % (Q_INT64_C(1000) * 1000 * 1000);
        }
    }
    return true;
}

wakeUp()

void QMutexPrivate::wakeUp

(

)

Definition at line 133 of file qmutex_unix.cpp.

Referenced by QMutex::unlock().

{
    (void) contenders.fetchAndStoreRelease(0);
    (void) _q_futex(&contenders._q_value, FUTEX_WAKE, 1, 0, 0, 0);
}

Properties

averageWaitTime

volatile qint64 QMutexPrivate::averageWaitTime

Definition at line 78 of file qmutex_p.h.

Referenced by QMutex::lockInternal().

count

uint QMutexPrivate::count

Definition at line 80 of file qmutex_p.h.

Referenced by QMutex::lock(), QMutex::tryLock(), and QMutex::unlock().

event

HANDLE QMutexPrivate::event

Definition at line 87 of file qmutex_p.h.

maximumSpinTime

volatile qint64 QMutexPrivate::maximumSpinTime

Definition at line 77 of file qmutex_p.h.

Referenced by QMutex::lockInternal().

owner

Qt::HANDLE QMutexPrivate::owner

Definition at line 79 of file qmutex_p.h.

Referenced by QMutex::lock(), QMutex::tryLock(), and QMutex::unlock().

---

The documentation for this class was generated from the following files:

• /src/corelib/thread/qmutex_p.h
• /src/corelib/thread/qmutex_unix.cpp
• /src/corelib/thread/qmutex_win.cpp