backends/drm: move damage tracking into GbmSurface

src/backends/drm/egl_gbm_backend.cpp

@@ -70,7 +70,7 @@ void EglGbmBackend::cleanupSurfaces()
 void EglGbmBackend::cleanupRenderData(Output::RenderData &render)
 {
     if (render.shadowBuffer) {
-        render.gbmSurface->makeContextCurrent();
+        render.gbmSurface->makeContextCurrent({});
         render.shadowBuffer = nullptr;
     }
     render.importSwapchain = nullptr;
@@ -198,7 +198,7 @@ bool EglGbmBackend::resetOutput(Output &output)
     if (!output.output->needsSoftwareTransformation())  {
         output.current.shadowBuffer = nullptr;
     } else {
-        output.current.gbmSurface->makeContextCurrent();
+        output.current.gbmSurface->makeContextCurrent({});
         output.current.shadowBuffer = QSharedPointer<ShadowBuffer>::create(output.output->sourceSize(), output.current.format);
         if (!output.current.shadowBuffer->isComplete()) {
             return false;
@@ -237,9 +237,8 @@ bool EglGbmBackend::swapBuffers(DrmAbstractOutput *drmOutput, const QRegion &dir
     if (output.current.shadowBuffer) {
         output.current.shadowBuffer->render(output.output);
     }
-    if (output.current.gbmSurface->swapBuffers()) {
+    if (output.current.gbmSurface->swapBuffers(dirty)) {
         cleanupRenderData(output.old);
-        updateBufferAge(output, dirty);
         return true;
     } else {
         return false;
@@ -467,7 +466,7 @@ void EglGbmBackend::aboutToStartPainting(AbstractOutput *drmOutput, const QRegio
     Q_ASSERT_X(drmOutput, "aboutToStartPainting", "not using per screen rendering");
     Q_ASSERT(m_outputs.contains(drmOutput));
     const Output &output = m_outputs[drmOutput];
-    if (output.current.bufferAge > 0 && !damagedRegion.isEmpty() && supportsPartialUpdate()) {
+    if (output.current.gbmSurface->bufferAge() > 0 && !damagedRegion.isEmpty() && supportsPartialUpdate()) {
         const QRegion region = damagedRegion & output.output->geometry();
 
         QVector<EGLint> rects = regionToRects(region, output.output);
@@ -553,19 +552,13 @@ QRegion EglGbmBackend::prepareRenderingForOutput(Output &output)
             resetOutput(output);
         }
     }
-    output.current.gbmSurface->makeContextCurrent();
-    if (output.current.shadowBuffer) {
-        output.current.shadowBuffer->bind();
+    auto &current = output.current;
+    const auto needsRepaint = current.gbmSurface->makeContextCurrent(output.output->geometry());
+    if (current.shadowBuffer) {
+        current.shadowBuffer->bind();
     }
     setViewport(output);
-
-    const QRect geometry = output.output->geometry();
-    if (supportsBufferAge()) {
-        auto current = &output.current;
-        return current->damageJournal.accumulate(current->bufferAge, geometry);
-    }
-
-    return geometry;
+    return needsRepaint;
 }
 
 QSharedPointer<DrmBuffer> EglGbmBackend::endFrameWithBuffer(AbstractOutput *drmOutput, const QRegion &dirty)
@@ -576,11 +569,7 @@ QSharedPointer<DrmBuffer> EglGbmBackend::endFrameWithBuffer(AbstractOutput *drmO
         if (output.current.shadowBuffer) {
             output.current.shadowBuffer->render(output.output);
         }
-        auto buffer = output.current.gbmSurface->swapBuffersForDrm();
-        if (buffer) {
-            updateBufferAge(output, dirty);
-        }
-        return buffer;
+        return output.current.gbmSurface->swapBuffersForDrm(dirty);
     } else {
         return importFramebuffer(output, dirty);
     }
@@ -600,14 +589,6 @@ void EglGbmBackend::endFrame(AbstractOutput *drmOutput, const QRegion &renderedR
     output.output->present(buffer, dirty);
 }
 
-void EglGbmBackend::updateBufferAge(Output &output, const QRegion &dirty)
-{
-    if (supportsBufferAge()) {
-        eglQuerySurface(eglDisplay(), output.current.gbmSurface->eglSurface(), EGL_BUFFER_AGE_EXT, &output.current.bufferAge);
-        output.current.damageJournal.add(dirty);
-    }
-}
-
 bool EglGbmBackend::scanout(AbstractOutput *drmOutput, SurfaceItem *surfaceItem)
 {
     static bool valid;

src/backends/drm/egl_gbm_backend.h

@@ -99,8 +99,6 @@ private:
         struct RenderData {
             QSharedPointer<ShadowBuffer> shadowBuffer;
             QSharedPointer<GbmSurface> gbmSurface;
-            int bufferAge = 0;
-            DamageJournal damageJournal;
             GbmFormat format;
 
             // for secondary GPU import
@@ -126,7 +124,6 @@ private:
     QRegion prepareRenderingForOutput(Output &output);
     QSharedPointer<DrmBuffer> importFramebuffer(Output &output, const QRegion &dirty) const;
     QSharedPointer<DrmBuffer> endFrameWithBuffer(AbstractOutput *output, const QRegion &dirty);
-    void updateBufferAge(Output &output, const QRegion &dirty);
     std::optional<GbmFormat> chooseFormat(Output &output) const;
 
     void cleanupRenderData(Output::RenderData &output);

src/backends/drm/gbm_surface.cpp

@@ -66,19 +66,24 @@ GbmSurface::~GbmSurface()
         gbm_surface_destroy(m_surface);
     }
 }
-bool GbmSurface::makeContextCurrent() const
+
+QRegion GbmSurface::makeContextCurrent(const QRect &geometry) const
 {
     if (eglMakeCurrent(m_gpu->eglDisplay(), m_eglSurface, m_eglSurface, m_gpu->eglBackend()->context()) == EGL_FALSE) {
         qCCritical(KWIN_DRM) << "eglMakeCurrent failed:" << getEglErrorString();
-        return false;
+        return {};
     }
     if (!GLPlatform::instance()->isGLES()) {
         glDrawBuffer(GL_BACK);
     }
-    return true;
+    if (m_gpu->eglBackend()->supportsBufferAge()) {
+        return m_damageJournal.accumulate(m_bufferAge, geometry);
+    } else {
+        return geometry;
+    }
 }
 
-QSharedPointer<DrmGbmBuffer> GbmSurface::swapBuffersForDrm()
+QSharedPointer<DrmGbmBuffer> GbmSurface::swapBuffersForDrm(const QRegion &dirty)
 {
     auto error = eglSwapBuffers(m_gpu->eglDisplay(), m_eglSurface);
     if (error != EGL_TRUE) {
@@ -96,10 +101,14 @@ QSharedPointer<DrmGbmBuffer> GbmSurface::swapBuffersForDrm()
         return nullptr;
     }
     m_currentDrmBuffer = buffer;
+    if (m_gpu->eglBackend()->supportsBufferAge()) {
+        eglQuerySurface(m_gpu->eglDisplay(), m_eglSurface, EGL_BUFFER_AGE_EXT, &m_bufferAge);
+        m_damageJournal.add(dirty);
+    }
     return buffer;
 }
 
-QSharedPointer<GbmBuffer> GbmSurface::swapBuffers()
+QSharedPointer<GbmBuffer> GbmSurface::swapBuffers(const QRegion &dirty)
 {
     auto error = eglSwapBuffers(m_gpu->eglDisplay(), m_eglSurface);
     if (error != EGL_TRUE) {
@@ -112,6 +121,10 @@ QSharedPointer<GbmBuffer> GbmSurface::swapBuffers()
     }
     m_currentBuffer = QSharedPointer<GbmBuffer>::create(this, bo);
     m_lockedBuffers << m_currentBuffer.get();
+    if (m_gpu->eglBackend()->supportsBufferAge()) {
+        eglQuerySurface(m_gpu->eglDisplay(), m_eglSurface, EGL_BUFFER_AGE_EXT, &m_bufferAge);
+        m_damageJournal.add(dirty);
+    }
     return m_currentBuffer;
 }
 
@@ -156,4 +169,9 @@ QVector<uint64_t> GbmSurface::modifiers() const
     return m_modifiers;
 }
 
+int GbmSurface::bufferAge() const
+{
+    return m_bufferAge;
+}
+
 }

src/backends/drm/gbm_surface.h

@@ -14,6 +14,7 @@
 #include <QVector>
 
 #include "drm_buffer_gbm.h"
+#include "utils/common.h"
 
 struct gbm_device;
 struct gbm_surface;
@@ -28,10 +29,10 @@ public:
     explicit GbmSurface(DrmGpu *gpu, const QSize &size, uint32_t format, QVector<uint64_t> modifiers, EGLConfig config);
     ~GbmSurface();
 
-    bool makeContextCurrent() const;
+    QRegion makeContextCurrent(const QRect &geometry) const;
 
-    QSharedPointer<DrmGbmBuffer> swapBuffersForDrm();
-    QSharedPointer<GbmBuffer> swapBuffers();
+    QSharedPointer<DrmGbmBuffer> swapBuffersForDrm(const QRegion &dirty);
+    QSharedPointer<GbmBuffer> swapBuffers(const QRegion &dirty);
     void releaseBuffer(GbmBuffer *buffer);
 
     QSharedPointer<GbmBuffer> currentBuffer() const;
@@ -42,6 +43,7 @@ public:
     bool isValid() const;
     uint32_t format() const;
     QVector<uint64_t> modifiers() const;
+    int bufferAge() const;
 
 private:
     gbm_surface *m_surface;
@@ -50,6 +52,8 @@ private:
     QSize m_size;
     const uint32_t m_format;
     const QVector<uint64_t> m_modifiers;
+    int m_bufferAge = 0;
+    DamageJournal m_damageJournal;
 
     QSharedPointer<GbmBuffer> m_currentBuffer;
     QSharedPointer<DrmGbmBuffer> m_currentDrmBuffer;