From a83e65ddc9a965b25e435d136849a50f0b99c4ae Mon Sep 17 00:00:00 2001 From: Paul Olav Tvete Date: Tue, 15 Mar 2022 16:53:04 +0100 Subject: [PATCH 37/38] Fix race condition on mWaitingForUpdateDelivery Change-Id: I0e91bda73722468b9339fc434fe04420b5e7d3da Reviewed-by: David Edmundson --- src/client/qwaylandwindow.cpp | 7 ++----- src/client/qwaylandwindow_p.h | 2 +- 2 files changed, 3 insertions(+), 6 deletions(-) diff --git a/src/client/qwaylandwindow.cpp b/src/client/qwaylandwindow.cpp index bf41cc5b..ceaa4c73 100644 --- a/src/client/qwaylandwindow.cpp +++ b/src/client/qwaylandwindow.cpp @@ -649,24 +649,21 @@ void QWaylandWindow::handleFrameCallback() // The rest can wait until we can run it on the correct thread auto doHandleExpose = [this]() { + mWaitingForUpdateDelivery.storeRelease(false); bool wasExposed = isExposed(); mFrameCallbackTimedOut = false; if (!wasExposed && isExposed()) // Did setting mFrameCallbackTimedOut make the window exposed? sendExposeEvent(QRect(QPoint(), geometry().size())); if (wasExposed && hasPendingUpdateRequest()) deliverUpdateRequest(); - - mWaitingForUpdateDelivery = false; }; - if (!mWaitingForUpdateDelivery) { + if (mWaitingForUpdateDelivery.testAndSetAcquire(false, true)) { // Queued connection, to make sure we don't call handleUpdate() from inside waitForFrameSync() // in the single-threaded case. - mWaitingForUpdateDelivery = true; QMetaObject::invokeMethod(this, doHandleExpose, Qt::QueuedConnection); } - mFrameSyncWait.notify_all(); } diff --git a/src/client/qwaylandwindow_p.h b/src/client/qwaylandwindow_p.h index d45980a8..cb9135f6 100644 --- a/src/client/qwaylandwindow_p.h +++ b/src/client/qwaylandwindow_p.h @@ -228,7 +228,7 @@ protected: WId mWindowId; bool mWaitingForFrameCallback = false; bool mFrameCallbackTimedOut = false; // Whether the frame callback has timed out - bool mWaitingForUpdateDelivery = false; + QAtomicInt mWaitingForUpdateDelivery = false; int mFrameCallbackCheckIntervalTimerId = -1; QElapsedTimer mFrameCallbackElapsedTimer; struct ::wl_callback *mFrameCallback = nullptr; -- 2.36.1