From 29cba30948cda34e744314343109964ff9ed515c Mon Sep 17 00:00:00 2001 From: Erik Kurzinger Date: Tue, 11 May 2021 17:00:21 -0400 Subject: [PATCH xserver 22/27] xwayland/eglstream: flush stream after eglSwapBuffers When eglSwapBuffers inserts a new frame into a window's stream, there may be a delay before the state of the consumer end of the stream is updated to reflect this. If the subsequent wl_surface_attach, wl_surface_damage, wl_surface_commit calls are received by the compositor before then, it will (typically) re-use the previous frame acquired from the stream instead of the latest one. This can leave the window displaying out-of-date contents, which might never be updated thereafter. To fix this, after calling eglSwapBuffers, xwl_glamor_eglstream_post_damage should call eglStreamFlushNV. This call will block until it can be guaranteed that the state of the consumer end of the stream has been updated to reflect that a new frame is available. Closes: https://gitlab.freedesktop.org/xorg/xserver/-/issues/1171 Signed-off-by: Erik Kurzinger (cherry picked from commit 7515c23a416825f0db51f9b445279b12d5918ebf) --- hw/xwayland/xwayland-glamor-eglstream.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/hw/xwayland/xwayland-glamor-eglstream.c b/hw/xwayland/xwayland-glamor-eglstream.c index 2d0827709..c583a1390 100644 --- a/hw/xwayland/xwayland-glamor-eglstream.c +++ b/hw/xwayland/xwayland-glamor-eglstream.c @@ -72,6 +72,7 @@ struct xwl_eglstream_private { SetWindowPixmapProcPtr SetWindowPixmap; Bool have_egl_damage; + Bool have_egl_stream_flush; GLint blit_prog; GLuint blit_vao; @@ -776,6 +777,13 @@ xwl_glamor_eglstream_post_damage(struct xwl_window *xwl_window, goto out; } +#ifdef EGL_NV_stream_flush + if (xwl_eglstream->have_egl_stream_flush) + /* block until stream state is updated on the compositor's side */ + eglStreamFlushNV(xwl_screen->egl_display, + xwl_pixmap->stream); +#endif + if (!xwl_pixmap->wait_for_buffer_release) { /* hang onto the pixmap until the compositor has released it */ pixmap->refcnt++; @@ -1173,6 +1181,18 @@ xwl_glamor_eglstream_init_egl(struct xwl_screen *xwl_screen) ErrorF("Driver lacks EGL_KHR_swap_buffers_with_damage, performance " "will be affected\n"); +#ifdef EGL_NV_stream_flush + xwl_eglstream->have_egl_stream_flush = + epoxy_has_egl_extension(xwl_screen->egl_display, + "EGL_NV_stream_flush"); +#else + xwl_eglstream->have_egl_stream_flush = FALSE; +#endif /* EGL_NV_stream_flush */ + + if (!xwl_eglstream->have_egl_stream_flush) + ErrorF("EGL_NV_stream_flush not available, " + "this may cause visible corruption.\n"); + xwl_eglstream_init_shaders(xwl_screen); if (epoxy_has_gl_extension("GL_OES_EGL_image") && -- 2.31.1