backends/drm: suppress logging for direct scanout

BUG: 456089

src/backends/drm/drm_buffer.cpp

@@ -150,7 +150,6 @@ std::shared_ptr<DrmFramebuffer> DrmFramebuffer::createFramebuffer(const std::sha
     if (ret == 0) {
         return std::make_shared<DrmFramebuffer>(buffer, framebufferId);
     } else {
-        qCWarning(KWIN_DRM) << "Could not create drm framebuffer!" << strerror(errno);
         return nullptr;
     }
 }

src/backends/drm/drm_lease_egl_gbm_layer.cpp

@@ -42,6 +42,9 @@ bool DrmLeaseEglGbmLayer::checkTestBuffer()
         }
         if (newBo) {
             m_framebuffer = DrmFramebuffer::createFramebuffer(std::make_shared<GbmBuffer>(m_pipeline->gpu(), newBo));
+            if (!m_framebuffer) {
+                qCWarning(KWIN_DRM, "Failed to create gbm framebuffer for lease output: %s", strerror(errno));
+            }
         } else {
             qCWarning(KWIN_DRM) << "Failed to create gbm_bo for lease output";
         }

src/backends/drm/drm_qpainter_layer.cpp

@@ -16,6 +16,7 @@
 #include "drm_pipeline.h"
 #include "drm_virtual_output.h"
 #include "dumb_swapchain.h"
+#include "logging.h"
 #include "scene_qpainter_drm_backend.h"
 
 #include <drm_fourcc.h>
@@ -49,6 +50,9 @@ bool DrmQPainterLayer::endFrame(const QRegion &renderedRegion, const QRegion &da
     m_currentDamage = damagedRegion;
     m_swapchain->releaseBuffer(m_swapchain->currentBuffer(), damagedRegion);
     m_currentFramebuffer = DrmFramebuffer::createFramebuffer(m_swapchain->currentBuffer());
+    if (!m_currentFramebuffer) {
+        qCWarning(KWIN_DRM, "Failed to create dumb framebuffer: %s", strerror(errno));
+    }
     return m_currentFramebuffer != nullptr;
 }
 
@@ -58,6 +62,9 @@ bool DrmQPainterLayer::checkTestBuffer()
         m_swapchain = std::make_shared<DumbSwapchain>(m_pipeline->gpu(), m_pipeline->bufferSize(), DRM_FORMAT_XRGB8888);
         if (!m_swapchain->isEmpty()) {
             m_currentFramebuffer = DrmFramebuffer::createFramebuffer(m_swapchain->currentBuffer());
+            if (!m_currentFramebuffer) {
+                qCWarning(KWIN_DRM, "Failed to create dumb framebuffer: %s", strerror(errno));
+            }
         } else {
             m_currentFramebuffer.reset();
         }
@@ -110,6 +117,9 @@ bool DrmCursorQPainterLayer::endFrame(const QRegion &damagedRegion, const QRegio
     Q_UNUSED(renderedRegion)
     m_swapchain->releaseBuffer(m_swapchain->currentBuffer(), damagedRegion);
     m_currentFramebuffer = DrmFramebuffer::createFramebuffer(m_swapchain->currentBuffer());
+    if (!m_currentFramebuffer) {
+        qCWarning(KWIN_DRM, "Failed to create dumb framebuffer for the cursor: %s", strerror(errno));
+    }
     return m_currentFramebuffer != nullptr;
 }
 
@@ -177,6 +187,9 @@ bool DrmLeaseQPainterLayer::checkTestBuffer()
         m_buffer = DrmDumbBuffer::createDumbBuffer(m_pipeline->gpu(), size, DRM_FORMAT_XRGB8888);
         if (m_buffer) {
             m_framebuffer = DrmFramebuffer::createFramebuffer(m_buffer);
+            if (!m_framebuffer) {
+                qCWarning(KWIN_DRM, "Failed to create dumb framebuffer for lease output: %s", strerror(errno));
+            }
         } else {
             m_framebuffer.reset();
         }

src/backends/drm/egl_gbm_layer_surface.cpp

@@ -129,7 +129,11 @@ std::optional<std::tuple<std::shared_ptr<DrmFramebuffer>, QRegion>> EglGbmLayerS
     if (m_gpu == m_eglBackend->gpu()) {
         if (const auto buffer = m_gbmSurface->swapBuffers(damagedRegion)) {
             m_currentBuffer = buffer;
-            return std::tuple(DrmFramebuffer::createFramebuffer(buffer), damagedRegion);
+            auto ret = DrmFramebuffer::createFramebuffer(buffer);
+            if (!ret) {
+                qCWarning(KWIN_DRM, "Failed to create framebuffer for EglGbmLayerSurface: %s", strerror(errno));
+            }
+            return std::tuple(ret, damagedRegion);
         }
     } else {
         if (const auto gbmBuffer = m_gbmSurface->swapBuffers(damagedRegion)) {
@@ -282,7 +286,11 @@ std::shared_ptr<DrmFramebuffer> EglGbmLayerSurface::importDmabuf()
         qCWarning(KWIN_DRM, "failed to import gbm_bo for multi-gpu usage: %s", strerror(errno));
         return nullptr;
     }
-    return DrmFramebuffer::createFramebuffer(imported);
+    const auto ret = DrmFramebuffer::createFramebuffer(imported);
+    if (!ret) {
+        qCWarning(KWIN_DRM, "Failed to create framebuffer for multi-gpu: %s", strerror(errno));
+    }
+    return ret;
 }
 
 std::shared_ptr<DrmFramebuffer> EglGbmLayerSurface::importWithCpu()
@@ -313,7 +321,11 @@ std::shared_ptr<DrmFramebuffer> EglGbmLayerSurface::importWithCpu()
     if (!memcpy(importBuffer->data(), m_currentBuffer->mappedData(), importBuffer->size().height() * importBuffer->strides()[0])) {
         return nullptr;
     }
-    return DrmFramebuffer::createFramebuffer(importBuffer);
+    const auto ret = DrmFramebuffer::createFramebuffer(importBuffer);
+    if (!ret) {
+        qCWarning(KWIN_DRM, "Failed to create framebuffer for CPU import: %s", strerror(errno));
+    }
+    return ret;
 }
 
 bool EglGbmLayerSurface::doesSwapchainFit(DumbSwapchain *swapchain) const
@@ -364,7 +376,11 @@ std::shared_ptr<DrmFramebuffer> EglGbmLayerSurface::renderTestBuffer(const QSize
                 return nullptr;
             }
         }
-        return DrmFramebuffer::createFramebuffer(m_currentBuffer);
+        const auto ret = DrmFramebuffer::createFramebuffer(m_currentBuffer);
+        if (!ret) {
+            qCWarning(KWIN_DRM, "Failed to create framebuffer for testing: %s", strerror(errno));
+        }
+        return ret;
     } else {
         return nullptr;
     }