diff options
Diffstat (limited to 'src/dbus/qdbusintegrator.cpp')
-rw-r--r-- | src/dbus/qdbusintegrator.cpp | 89 |
1 files changed, 88 insertions, 1 deletions
diff --git a/src/dbus/qdbusintegrator.cpp b/src/dbus/qdbusintegrator.cpp index 499e9dbd82..468859fdec 100644 --- a/src/dbus/qdbusintegrator.cpp +++ b/src/dbus/qdbusintegrator.cpp @@ -42,6 +42,7 @@ #include "qdbusintegrator_p.h" #include <qcoreapplication.h> +#include <qelapsedtimer.h> #include <qdebug.h> #include <qmetaobject.h> #include <qobject.h> @@ -1932,9 +1933,95 @@ int QDBusConnectionPrivate::send(const QDBusMessage& message) return serial; } +// small helper to note long running blocking dbus calls. +// these are generally a sign of fragile software (too long a call can either +// lead to bad user experience, if it's running on the GUI thread for instance) +// or break completely under load (hitting the call timeout). +// +// as a result, this is something we want to watch for. +class QDBusBlockingCallWatcher +{ +public: + QDBusBlockingCallWatcher(const QDBusMessage &message) + : m_message(message), m_maxCallTimeoutMs(0) + { +#if defined(QT_NO_DEBUG) + // when in a release build, we default these to off. + // this means that we only affect code that explicitly enables the warning. + static int mainThreadWarningAmount = -1; + static int otherThreadWarningAmount = -1; +#else + static int mainThreadWarningAmount = 200; + static int otherThreadWarningAmount = 500; +#endif + static bool initializedAmounts = false; + static QBasicMutex initializeMutex; + QMutexLocker locker(&initializeMutex); + + if (!initializedAmounts) { + int tmp = 0; + QByteArray env; + bool ok = true; + + env = qgetenv("Q_DBUS_BLOCKING_CALL_MAIN_THREAD_WARNING_MS"); + if (!env.isEmpty()) { + tmp = env.toInt(&ok); + if (ok) + mainThreadWarningAmount = tmp; + else + qWarning("QDBusBlockingCallWatcher: Q_DBUS_BLOCKING_CALL_MAIN_THREAD_WARNING_MS must be an integer; value ignored"); + } + + env = qgetenv("Q_DBUS_BLOCKING_CALL_OTHER_THREAD_WARNING_MS"); + if (!env.isEmpty()) { + tmp = env.toInt(&ok); + if (ok) + otherThreadWarningAmount = tmp; + else + qWarning("QDBusBlockingCallWatcher: Q_DBUS_BLOCKING_CALL_OTHER_THREAD_WARNING_MS must be an integer; value ignored"); + } + + initializedAmounts = true; + } + + locker.unlock(); + + // if this call is running on the main thread, we have a much lower + // tolerance for delay because any long-term delay will wreck user + // interactivity. + if (qApp && qApp->thread() == QThread::currentThread()) + m_maxCallTimeoutMs = mainThreadWarningAmount; + else + m_maxCallTimeoutMs = otherThreadWarningAmount; + + m_callTimer.start(); + } + + ~QDBusBlockingCallWatcher() + { + if (m_maxCallTimeoutMs < 0) + return; // disabled + + if (m_callTimer.elapsed() >= m_maxCallTimeoutMs) { + qWarning("QDBusConnection: warning: blocking call took a long time (%d ms, max for this thread is %d ms) to service \"%s\" path \"%s\" interface \"%s\" member \"%s\"", + int(m_callTimer.elapsed()), m_maxCallTimeoutMs, + qPrintable(m_message.service()), qPrintable(m_message.path()), + qPrintable(m_message.interface()), qPrintable(m_message.member())); + } + } + +private: + QDBusMessage m_message; + int m_maxCallTimeoutMs; + QElapsedTimer m_callTimer; +}; + + QDBusMessage QDBusConnectionPrivate::sendWithReply(const QDBusMessage &message, int sendMode, int timeout) { + QDBusBlockingCallWatcher watcher(message); + checkThread(); if ((sendMode == QDBus::BlockWithGui || sendMode == QDBus::Block) && isServiceRegisteredByThread(message.service())) @@ -2266,7 +2353,7 @@ QDBusConnectionPrivate::disconnectSignal(SignalHookHash::Iterator &it) watchedServices.erase(sit); disconnectSignal(dbusServiceString(), QString(), dbusInterfaceString(), QLatin1String("NameOwnerChanged"), QStringList() << hook.service, QString(), - this, SLOT(_q_serviceOwnerChanged(QString,QString,QString))); + this, SLOT(serviceOwnerChangedNoLock(QString,QString,QString))); } } } |