File 0002-Client-Improve-thread-safety-determining-w... of Package qt6-wayland

Overview Repositories Revisions Requests Users Attributes Meta

File 0002-Client-Improve-thread-safety-determining-window-size.patch of Package qt6-wayland

From be646fd42892d6e59a573a0a188c5ae193d2be83 Mon Sep 17 00:00:00 2001
From: David Edmundson <davidedmundson@kde.org>
Date: Fri, 5 Jul 2024 16:13:40 +0100
Subject: [PATCH 2/2] Client: Improve thread safety determining window size on
 the render thread

updateSurface is called from both the render and GUI thread. We
therefore need every property referenced to be thread safe.

Rather than guarding each property we cache the buffer size whenever the
window geometry or scale changes and put a mutex round this one
variable.

Change-Id: I4168ced27556e0e4558bbdbd1daa275d7523c33d
Reviewed-by: Vlad Zahorodnii <vlad.zahorodnii@kde.org>
(cherry picked from commit 83da29c62f8fb918df8d91826d16b5d5ceb2c704)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
(cherry picked from commit f817608c7152487f489d0f3a227c1d0ceb7b0c2c)
---
 .../client/wayland-egl/qwaylandeglwindow.cpp  | 20 +++++++++++++++----
 .../client/wayland-egl/qwaylandeglwindow_p.h  |  6 ++++++
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow.cpp b/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow.cpp
index e6258893..d020f4db 100644
--- a/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow.cpp
+++ b/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow.cpp
@@ -50,6 +50,15 @@ QWaylandWindow::WindowType QWaylandEglWindow::windowType() const
 
 void QWaylandEglWindow::ensureSize()
 {
+    // this is always called on the main thread
+    QMargins margins = mWindowDecoration ? frameMargins() : QMargins{};
+    QRect rect = geometry();
+    QSize sizeWithMargins = (rect.size() + QSize(margins.left() + margins.right(), margins.top() + margins.bottom())) * scale();
+    {
+        QWriteLocker lock(&m_bufferSizeLock);
+        m_bufferSize = sizeWithMargins;
+    }
+
     updateSurface(false);
 }
 
@@ -60,14 +69,17 @@ void QWaylandEglWindow::setGeometry(const QRect &rect)
     // we're now getting a resize we don't want to create it again.
     // Just resize the wl_egl_window, the EGLSurface will be created
     // the next time makeCurrent is called.
-    updateSurface(false);
+    ensureSize();
 }
 
 void QWaylandEglWindow::updateSurface(bool create)
 {
-    QMargins margins = mWindowDecoration ? frameMargins() : QMargins{};
-    QRect rect = geometry();
-    QSize sizeWithMargins = (rect.size() + QSize(margins.left() + margins.right(), margins.top() + margins.bottom())) * scale();
+
+    QSize sizeWithMargins;
+    {
+        QReadLocker lock(&m_bufferSizeLock);
+        sizeWithMargins = m_bufferSize;
+    }
 
     // wl_egl_windows must have both width and height > 0
     // mesa's egl returns NULL if we try to create a, invalid wl_egl_window, however not all EGL
diff --git a/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow_p.h b/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow_p.h
index 5b9aa987..048f0b61 100644
--- a/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow_p.h
+++ b/src/hardwareintegration/client/wayland-egl/qwaylandeglwindow_p.h
@@ -60,7 +60,13 @@ private:
     mutable QOpenGLFramebufferObject *m_contentFBO = nullptr;
 
     QSurfaceFormat m_format;
+    // Size used in the last call to wl_egl_window_resize
     QSize m_requestedSize;
+
+    // Size of the buffer used by QWaylandWindow
+    // This is always written to from the main thread, potentially read from the rendering thread
+    QReadWriteLock m_bufferSizeLock;
+    QSize m_bufferSize;
 };
 
 }
-- 
2.45.2

Places

File 0002-Client-Improve-thread-safety-determining-window-size.patch of Package qt6-wayland

Places